Merge branch 'master' of master.kernel.org:/pub/scm/linux/kernel/git/torvalds/linux-2.6

Conflicts: Documentation/powerpc/booting-without-of.txt drivers/atm/Makefile drivers/net/fs_enet/fs_enet-main.c drivers/pci/pci-acpi.c net/8021q/vlan.c net/iucv/iucv.c
author: David S. Miller <davem@davemloft.net> 2008-07-18 02:39:39 -0700
committer: David S. Miller <davem@davemloft.net> 2008-07-18 02:39:39 -0700
commit: 49997d75152b3d23c53b0fa730599f2f74c92c65 (patch)
tree: 46e93126170d02cfec9505172e545732c1b69656 /fs
parent: a0c80b80e0fb48129e4e9d6a9ede914f9ff1850d (diff)
parent: 5b664cb235e97afbf34db9c4d77f08ebd725335e (diff)
182 files changed, 39659 insertions, 4464 deletions
diff --git a/fs/9p/v9fs_vfs.h b/fs/9p/v9fs_vfs.h
index fd01d90cada..57997fa14e6 100644
--- a/fs/9p/v9fs_vfs.h
+++ b/fs/9p/v9fs_vfs.h
@@ -51,4 +51,4 @@ int v9fs_dir_release(struct inode *inode, struct file *filp);
 int v9fs_file_open(struct inode *inode, struct file *file);
 void v9fs_inode2stat(struct inode *inode, struct p9_stat *stat);
 void v9fs_dentry_release(struct dentry *);
-int v9fs_uflags2omode(int uflags);
+int v9fs_uflags2omode(int uflags, int extended);
diff --git a/fs/9p/vfs_file.c b/fs/9p/vfs_file.c
index 0d55affe37d..52944d2249a 100644
--- a/fs/9p/vfs_file.c
+++ b/fs/9p/vfs_file.c
@@ -59,7 +59,7 @@ int v9fs_file_open(struct inode *inode, struct file *file)
 
 	P9_DPRINTK(P9_DEBUG_VFS, "inode: %p file: %p \n", inode, file);
 	v9ses = v9fs_inode2v9ses(inode);
-	omode = v9fs_uflags2omode(file->f_flags);
+	omode = v9fs_uflags2omode(file->f_flags, v9fs_extended(v9ses));
 	fid = file->private_data;
 	if (!fid) {
 		fid = v9fs_fid_clone(file->f_path.dentry);
@@ -75,6 +75,8 @@ int v9fs_file_open(struct inode *inode, struct file *file)
 			inode->i_size = 0;
 			inode->i_blocks = 0;
 		}
+		if ((file->f_flags & O_APPEND) && (!v9fs_extended(v9ses)))
+			generic_file_llseek(file, 0, SEEK_END);
 	}
 
 	file->private_data = fid;
diff --git a/fs/9p/vfs_inode.c b/fs/9p/vfs_inode.c
index 40fa807bd92..c95295c6504 100644
--- a/fs/9p/vfs_inode.c
+++ b/fs/9p/vfs_inode.c
@@ -132,10 +132,10 @@ static int p9mode2unixmode(struct v9fs_session_info *v9ses, int mode)
 /**
  * v9fs_uflags2omode- convert posix open flags to plan 9 mode bits
  * @uflags: flags to convert
- *
+ * @extended: if .u extensions are active
  */
 
-int v9fs_uflags2omode(int uflags)
+int v9fs_uflags2omode(int uflags, int extended)
 {
 	int ret;
 
@@ -155,14 +155,16 @@ int v9fs_uflags2omode(int uflags)
 		break;
 	}
 
-	if (uflags & O_EXCL)
-		ret |= P9_OEXCL;
-
 	if (uflags & O_TRUNC)
 		ret |= P9_OTRUNC;
 
-	if (uflags & O_APPEND)
-		ret |= P9_OAPPEND;
+	if (extended) {
+		if (uflags & O_EXCL)
+			ret |= P9_OEXCL;
+
+		if (uflags & O_APPEND)
+			ret |= P9_OAPPEND;
+	}
 
 	return ret;
 }
@@ -506,7 +508,7 @@ v9fs_vfs_create(struct inode *dir, struct dentry *dentry, int mode,
 		flags = O_RDWR;
 
 	fid = v9fs_create(v9ses, dir, dentry, NULL, perm,
-						v9fs_uflags2omode(flags));
+				v9fs_uflags2omode(flags, v9fs_extended(v9ses)));
 	if (IS_ERR(fid)) {
 		err = PTR_ERR(fid);
 		fid = NULL;
diff --git a/fs/Kconfig b/fs/Kconfig
index cf12c403b8c..37db79a2ff9 100644
--- a/fs/Kconfig
+++ b/fs/Kconfig
@@ -470,6 +470,14 @@ config OCFS2_FS_USERSPACE_CLUSTER
 	  It is safe to say Y, as the clustering method is run-time
 	  selectable.
 
+config OCFS2_FS_STATS
+	bool "OCFS2 statistics"
+	depends on OCFS2_FS
+	default y
+	help
+	  This option allows some fs statistics to be captured. Enabling
+	  this option may increase the memory consumption.
+
 config OCFS2_DEBUG_MASKLOG
 	bool "OCFS2 logging support"
 	depends on OCFS2_FS
@@ -830,7 +838,7 @@ config NTFS_FS
 	  from the project web site.
 
 	  For more information see <file:Documentation/filesystems/ntfs.txt>
-	  and <http://linux-ntfs.sourceforge.net/>.
+	  and <http://www.linux-ntfs.org/>.
 
 	  To compile this file system support as a module, choose M here: the
 	  module will be called ntfs.
@@ -930,7 +938,7 @@ config PROC_KCORE
 
 config PROC_VMCORE
         bool "/proc/vmcore support (EXPERIMENTAL)"
-        depends on PROC_FS && EXPERIMENTAL && CRASH_DUMP
+        depends on PROC_FS && CRASH_DUMP
 	default y
         help
         Exports the dump image of crashed kernel in ELF format.
@@ -1375,6 +1383,9 @@ config JFFS2_CMODE_FAVOURLZO
 
 endchoice
 
+# UBIFS File system configuration
+source "fs/ubifs/Kconfig"
+
 config CRAMFS
 	tristate "Compressed ROM file system support (cramfs)"
 	depends on BLOCK
@@ -1544,10 +1555,6 @@ config UFS_FS
           The recently released UFS2 variant (used in FreeBSD 5.x) is
           READ-ONLY supported.
 
-	  If you only intend to mount files from some other Unix over the
-	  network using NFS, you don't need the UFS file system support (but
-	  you need NFS file system support obviously).
-
 	  Note that this option is generally not needed for floppies, since a
 	  good portable way to transport files and directories between unixes
 	  (and even other operating systems) is given by the tar program ("man
@@ -1587,6 +1594,7 @@ menuconfig NETWORK_FILESYSTEMS
 	  Say Y here to get to see options for network filesystems and
 	  filesystem-related networking code, such as NFS daemon and
 	  RPCSEC security modules.
+
 	  This option alone does not add any kernel code.
 
 	  If you say N, all options in this submenu will be skipped and
@@ -1595,76 +1603,92 @@ menuconfig NETWORK_FILESYSTEMS
 if NETWORK_FILESYSTEMS
 
 config NFS_FS
-	tristate "NFS file system support"
+	tristate "NFS client support"
 	depends on INET
 	select LOCKD
 	select SUNRPC
 	select NFS_ACL_SUPPORT if NFS_V3_ACL
 	help
-	  If you are connected to some other (usually local) Unix computer
-	  (using SLIP, PLIP, PPP or Ethernet) and want to mount files residing
-	  on that computer (the NFS server) using the Network File Sharing
-	  protocol, say Y. "Mounting files" means that the client can access
-	  the files with usual UNIX commands as if they were sitting on the
-	  client's hard disk. For this to work, the server must run the
-	  programs nfsd and mountd (but does not need to have NFS file system
-	  support enabled in its kernel). NFS is explained in the Network
-	  Administrator's Guide, available from
-	  <http://www.tldp.org/docs.html#guide>, on its man page: "man
-	  nfs", and in the NFS-HOWTO.
-
-	  A superior but less widely used alternative to NFS is provided by
-	  the Coda file system; see "Coda file system support" below.
+	  Choose Y here if you want to access files residing on other
+	  computers using Sun's Network File System protocol.  To compile
+	  this file system support as a module, choose M here: the module
+	  will be called nfs.
 
-	  If you say Y here, you should have said Y to TCP/IP networking also.
-	  This option would enlarge your kernel by about 27 KB.
+	  To mount file systems exported by NFS servers, you also need to
+	  install the user space mount.nfs command which can be found in
+	  the Linux nfs-utils package, available from http://linux-nfs.org/.
+	  Information about using the mount command is available in the
+	  mount(8) man page.  More detail about the Linux NFS client
+	  implementation is available via the nfs(5) man page.
 
-	  To compile this file system support as a module, choose M here: the
-	  module will be called nfs.
+	  Below you can choose which versions of the NFS protocol are
+	  available in the kernel to mount NFS servers.  Support for NFS
+	  version 2 (RFC 1094) is always available when NFS_FS is selected.
 
-	  If you are configuring a diskless machine which will mount its root
-	  file system over NFS at boot time, say Y here and to "Kernel
-	  level IP autoconfiguration" above and to "Root file system on NFS"
-	  below. You cannot compile this driver as a module in this case.
-	  There are two packages designed for booting diskless machines over
-	  the net: netboot, available from
-	  <http://ftp1.sourceforge.net/netboot/>, and Etherboot,
-	  available from <http://ftp1.sourceforge.net/etherboot/>.
+	  To configure a system which mounts its root file system via NFS
+	  at boot time, say Y here, select "Kernel level IP
+	  autoconfiguration" in the NETWORK menu, and select "Root file
+	  system on NFS" below.  You cannot compile this file system as a
+	  module in this case.
 
-	  If you don't know what all this is about, say N.
+	  If unsure, say N.
 
 config NFS_V3
-	bool "Provide NFSv3 client support"
+	bool "NFS client support for NFS version 3"
 	depends on NFS_FS
 	help
-	  Say Y here if you want your NFS client to be able to speak version
-	  3 of the NFS protocol.
+	  This option enables support for version 3 of the NFS protocol
+	  (RFC 1813) in the kernel's NFS client.
 
 	  If unsure, say Y.
 
 config NFS_V3_ACL
-	bool "Provide client support for the NFSv3 ACL protocol extension"
+	bool "NFS client support for the NFSv3 ACL protocol extension"
 	depends on NFS_V3
 	help
-	  Implement the NFSv3 ACL protocol extension for manipulating POSIX
-	  Access Control Lists.  The server should also be compiled with
-	  the NFSv3 ACL protocol extension; see the CONFIG_NFSD_V3_ACL option.
+	  Some NFS servers support an auxiliary NFSv3 ACL protocol that
+	  Sun added to Solaris but never became an official part of the
+	  NFS version 3 protocol.  This protocol extension allows
+	  applications on NFS clients to manipulate POSIX Access Control
+	  Lists on files residing on NFS servers.  NFS servers enforce
+	  ACLs on local files whether this protocol is available or not.
+
+	  Choose Y here if your NFS server supports the Solaris NFSv3 ACL
+	  protocol extension and you want your NFS client to allow
+	  applications to access and modify ACLs on files on the server.
+
+	  Most NFS servers don't support the Solaris NFSv3 ACL protocol
+	  extension.  You can choose N here or specify the "noacl" mount
+	  option to prevent your NFS client from trying to use the NFSv3
+	  ACL protocol.
 
 	  If unsure, say N.
 
 config NFS_V4
-	bool "Provide NFSv4 client support (EXPERIMENTAL)"
+	bool "NFS client support for NFS version 4 (EXPERIMENTAL)"
 	depends on NFS_FS && EXPERIMENTAL
 	select RPCSEC_GSS_KRB5
 	help
-	  Say Y here if you want your NFS client to be able to speak the newer
-	  version 4 of the NFS protocol.
+	  This option enables support for version 4 of the NFS protocol
+	  (RFC 3530) in the kernel's NFS client.
 
-	  Note: Requires auxiliary userspace daemons which may be found on
-		http://www.citi.umich.edu/projects/nfsv4/
+	  To mount NFS servers using NFSv4, you also need to install user
+	  space programs which can be found in the Linux nfs-utils package,
+	  available from http://linux-nfs.org/.
 
 	  If unsure, say N.
 
+config ROOT_NFS
+	bool "Root file system on NFS"
+	depends on NFS_FS=y && IP_PNP
+	help
+	  If you want your system to mount its root file system via NFS,
+	  choose Y here.  This is common practice for managing systems
+	  without local permanent storage.  For details, read
+	  <file:Documentation/filesystems/nfsroot.txt>.
+
+	  Most people say N here.
+
 config NFSD
 	tristate "NFS server support"
 	depends on INET
@@ -1746,20 +1770,6 @@ config NFSD_V4
 
 	  If unsure, say N.
 
-config ROOT_NFS
-	bool "Root file system on NFS"
-	depends on NFS_FS=y && IP_PNP
-	help
-	  If you want your Linux box to mount its whole root file system (the
-	  one containing the directory /) from some other computer over the
-	  net via NFS (presumably because your box doesn't have a hard disk),
-	  say Y. Read <file:Documentation/filesystems/nfsroot.txt> for
-	  details. It is likely that in this case, you also want to say Y to
-	  "Kernel level IP autoconfiguration" so that your box can discover
-	  its network address at boot time.
-
-	  Most people say N here.
-
 config LOCKD
 	tristate
 
@@ -1800,27 +1810,6 @@ config SUNRPC_XPRT_RDMA
 
 	  If unsure, say N.
 
-config SUNRPC_BIND34
-	bool "Support for rpcbind versions 3 & 4 (EXPERIMENTAL)"
-	depends on SUNRPC && EXPERIMENTAL
-	default n
-	help
-	  RPC requests over IPv6 networks require support for larger
-	  addresses when performing an RPC bind.  Sun added support for
-	  IPv6 addressing by creating two new versions of the rpcbind
-	  protocol (RFC 1833).
-
-	  This option enables support in the kernel RPC client for
-	  querying rpcbind servers via versions 3 and 4 of the rpcbind
-	  protocol.  The kernel automatically falls back to version 2
-	  if a remote rpcbind service does not support versions 3 or 4.
-	  By themselves, these new versions do not provide support for
-	  RPC over IPv6, but the new protocol versions are necessary to
-	  support it.
-
-	  If unsure, say N to get traditional behavior (version 2 rpcbind
-	  requests only).
-
 config RPCSEC_GSS_KRB5
 	tristate "Secure RPC: Kerberos V mechanism (EXPERIMENTAL)"
 	depends on SUNRPC && EXPERIMENTAL
diff --git a/fs/Makefile b/fs/Makefile
index 1e7a11bd4da..3b2178b4bb6 100644
--- a/fs/Makefile
+++ b/fs/Makefile
@@ -19,6 +19,7 @@ else
 obj-y +=	no-block.o
 endif
 
+obj-$(CONFIG_BLK_DEV_INTEGRITY) += bio-integrity.o
 obj-$(CONFIG_INOTIFY)		+= inotify.o
 obj-$(CONFIG_INOTIFY_USER)	+= inotify_user.o
 obj-$(CONFIG_EPOLL)		+= eventpoll.o
@@ -100,6 +101,7 @@ obj-$(CONFIG_NTFS_FS)		+= ntfs/
 obj-$(CONFIG_UFS_FS)		+= ufs/
 obj-$(CONFIG_EFS_FS)		+= efs/
 obj-$(CONFIG_JFFS2_FS)		+= jffs2/
+obj-$(CONFIG_UBIFS_FS)		+= ubifs/
 obj-$(CONFIG_AFFS_FS)		+= affs/
 obj-$(CONFIG_ROMFS_FS)		+= romfs/
 obj-$(CONFIG_QNX4FS_FS)		+= qnx4/
diff --git a/fs/bio-integrity.c b/fs/bio-integrity.c
new file mode 100644
index 00000000000..63e2ee63058
--- /dev/null
+++ b/fs/bio-integrity.c
@@ -0,0 +1,719 @@
+/*
+ * bio-integrity.c - bio data integrity extensions
+ *
+ * Copyright (C) 2007, 2008 Oracle Corporation
+ * Written by: Martin K. Petersen <martin.petersen@oracle.com>
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License version
+ * 2 as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; see the file COPYING.  If not, write to
+ * the Free Software Foundation, 675 Mass Ave, Cambridge, MA 02139,
+ * USA.
+ *
+ */
+
+#include <linux/blkdev.h>
+#include <linux/mempool.h>
+#include <linux/bio.h>
+#include <linux/workqueue.h>
+
+static struct kmem_cache *bio_integrity_slab __read_mostly;
+static struct workqueue_struct *kintegrityd_wq;
+
+/**
+ * bio_integrity_alloc_bioset - Allocate integrity payload and attach it to bio
+ * @bio:	bio to attach integrity metadata to
+ * @gfp_mask:	Memory allocation mask
+ * @nr_vecs:	Number of integrity metadata scatter-gather elements
+ * @bs:		bio_set to allocate from
+ *
+ * Description: This function prepares a bio for attaching integrity
+ * metadata.  nr_vecs specifies the maximum number of pages containing
+ * integrity metadata that can be attached.
+ */
+struct bio_integrity_payload *bio_integrity_alloc_bioset(struct bio *bio,
+							 gfp_t gfp_mask,
+							 unsigned int nr_vecs,
+							 struct bio_set *bs)
+{
+	struct bio_integrity_payload *bip;
+	struct bio_vec *iv;
+	unsigned long idx;
+
+	BUG_ON(bio == NULL);
+
+	bip = mempool_alloc(bs->bio_integrity_pool, gfp_mask);
+	if (unlikely(bip == NULL)) {
+		printk(KERN_ERR "%s: could not alloc bip\n", __func__);
+		return NULL;
+	}
+
+	memset(bip, 0, sizeof(*bip));
+
+	iv = bvec_alloc_bs(gfp_mask, nr_vecs, &idx, bs);
+	if (unlikely(iv == NULL)) {
+		printk(KERN_ERR "%s: could not alloc bip_vec\n", __func__);
+		mempool_free(bip, bs->bio_integrity_pool);
+		return NULL;
+	}
+
+	bip->bip_pool = idx;
+	bip->bip_vec = iv;
+	bip->bip_bio = bio;
+	bio->bi_integrity = bip;
+
+	return bip;
+}
+EXPORT_SYMBOL(bio_integrity_alloc_bioset);
+
+/**
+ * bio_integrity_alloc - Allocate integrity payload and attach it to bio
+ * @bio:	bio to attach integrity metadata to
+ * @gfp_mask:	Memory allocation mask
+ * @nr_vecs:	Number of integrity metadata scatter-gather elements
+ *
+ * Description: This function prepares a bio for attaching integrity
+ * metadata.  nr_vecs specifies the maximum number of pages containing
+ * integrity metadata that can be attached.
+ */
+struct bio_integrity_payload *bio_integrity_alloc(struct bio *bio,
+						  gfp_t gfp_mask,
+						  unsigned int nr_vecs)
+{
+	return bio_integrity_alloc_bioset(bio, gfp_mask, nr_vecs, fs_bio_set);
+}
+EXPORT_SYMBOL(bio_integrity_alloc);
+
+/**
+ * bio_integrity_free - Free bio integrity payload
+ * @bio:	bio containing bip to be freed
+ * @bs:		bio_set this bio was allocated from
+ *
+ * Description: Used to free the integrity portion of a bio. Usually
+ * called from bio_free().
+ */
+void bio_integrity_free(struct bio *bio, struct bio_set *bs)
+{
+	struct bio_integrity_payload *bip = bio->bi_integrity;
+
+	BUG_ON(bip == NULL);
+
+	/* A cloned bio doesn't own the integrity metadata */
+	if (!bio_flagged(bio, BIO_CLONED) && bip->bip_buf != NULL)
+		kfree(bip->bip_buf);
+
+	mempool_free(bip->bip_vec, bs->bvec_pools[bip->bip_pool]);
+	mempool_free(bip, bs->bio_integrity_pool);
+
+	bio->bi_integrity = NULL;
+}
+EXPORT_SYMBOL(bio_integrity_free);
+
+/**
+ * bio_integrity_add_page - Attach integrity metadata
+ * @bio:	bio to update
+ * @page:	page containing integrity metadata
+ * @len:	number of bytes of integrity metadata in page
+ * @offset:	start offset within page
+ *
+ * Description: Attach a page containing integrity metadata to bio.
+ */
+int bio_integrity_add_page(struct bio *bio, struct page *page,
+			   unsigned int len, unsigned int offset)
+{
+	struct bio_integrity_payload *bip = bio->bi_integrity;
+	struct bio_vec *iv;
+
+	if (bip->bip_vcnt >= bvec_nr_vecs(bip->bip_pool)) {
+		printk(KERN_ERR "%s: bip_vec full\n", __func__);
+		return 0;
+	}
+
+	iv = bip_vec_idx(bip, bip->bip_vcnt);
+	BUG_ON(iv == NULL);
+	BUG_ON(iv->bv_page != NULL);
+
+	iv->bv_page = page;
+	iv->bv_len = len;
+	iv->bv_offset = offset;
+	bip->bip_vcnt++;
+
+	return len;
+}
+EXPORT_SYMBOL(bio_integrity_add_page);
+
+/**
+ * bio_integrity_enabled - Check whether integrity can be passed
+ * @bio:	bio to check
+ *
+ * Description: Determines whether bio_integrity_prep() can be called
+ * on this bio or not.	bio data direction and target device must be
+ * set prior to calling.  The functions honors the write_generate and
+ * read_verify flags in sysfs.
+ */
+int bio_integrity_enabled(struct bio *bio)
+{
+	/* Already protected? */
+	if (bio_integrity(bio))
+		return 0;
+
+	return bdev_integrity_enabled(bio->bi_bdev, bio_data_dir(bio));
+}
+EXPORT_SYMBOL(bio_integrity_enabled);
+
+/**
+ * bio_integrity_hw_sectors - Convert 512b sectors to hardware ditto
+ * @bi:		blk_integrity profile for device
+ * @sectors:	Number of 512 sectors to convert
+ *
+ * Description: The block layer calculates everything in 512 byte
+ * sectors but integrity metadata is done in terms of the hardware
+ * sector size of the storage device.  Convert the block layer sectors
+ * to physical sectors.
+ */
+static inline unsigned int bio_integrity_hw_sectors(struct blk_integrity *bi,
+						    unsigned int sectors)
+{
+	/* At this point there are only 512b or 4096b DIF/EPP devices */
+	if (bi->sector_size == 4096)
+		return sectors >>= 3;
+
+	return sectors;
+}
+
+/**
+ * bio_integrity_tag_size - Retrieve integrity tag space
+ * @bio:	bio to inspect
+ *
+ * Description: Returns the maximum number of tag bytes that can be
+ * attached to this bio. Filesystems can use this to determine how
+ * much metadata to attach to an I/O.
+ */
+unsigned int bio_integrity_tag_size(struct bio *bio)
+{
+	struct blk_integrity *bi = bdev_get_integrity(bio->bi_bdev);
+
+	BUG_ON(bio->bi_size == 0);
+
+	return bi->tag_size * (bio->bi_size / bi->sector_size);
+}
+EXPORT_SYMBOL(bio_integrity_tag_size);
+
+int bio_integrity_tag(struct bio *bio, void *tag_buf, unsigned int len, int set)
+{
+	struct bio_integrity_payload *bip = bio->bi_integrity;
+	struct blk_integrity *bi = bdev_get_integrity(bio->bi_bdev);
+	unsigned int nr_sectors;
+
+	BUG_ON(bip->bip_buf == NULL);
+
+	if (bi->tag_size == 0)
+		return -1;
+
+	nr_sectors = bio_integrity_hw_sectors(bi,
+					DIV_ROUND_UP(len, bi->tag_size));
+
+	if (nr_sectors * bi->tuple_size > bip->bip_size) {
+		printk(KERN_ERR "%s: tag too big for bio: %u > %u\n",
+		       __func__, nr_sectors * bi->tuple_size, bip->bip_size);
+		return -1;
+	}
+
+	if (set)
+		bi->set_tag_fn(bip->bip_buf, tag_buf, nr_sectors);
+	else
+		bi->get_tag_fn(bip->bip_buf, tag_buf, nr_sectors);
+
+	return 0;
+}
+
+/**
+ * bio_integrity_set_tag - Attach a tag buffer to a bio
+ * @bio:	bio to attach buffer to
+ * @tag_buf:	Pointer to a buffer containing tag data
+ * @len:	Length of the included buffer
+ *
+ * Description: Use this function to tag a bio by leveraging the extra
+ * space provided by devices formatted with integrity protection.  The
+ * size of the integrity buffer must be <= to the size reported by
+ * bio_integrity_tag_size().
+ */
+int bio_integrity_set_tag(struct bio *bio, void *tag_buf, unsigned int len)
+{
+	BUG_ON(bio_data_dir(bio) != WRITE);
+
+	return bio_integrity_tag(bio, tag_buf, len, 1);
+}
+EXPORT_SYMBOL(bio_integrity_set_tag);
+
+/**
+ * bio_integrity_get_tag - Retrieve a tag buffer from a bio
+ * @bio:	bio to retrieve buffer from
+ * @tag_buf:	Pointer to a buffer for the tag data
+ * @len:	Length of the target buffer
+ *
+ * Description: Use this function to retrieve the tag buffer from a
+ * completed I/O. The size of the integrity buffer must be <= to the
+ * size reported by bio_integrity_tag_size().
+ */
+int bio_integrity_get_tag(struct bio *bio, void *tag_buf, unsigned int len)
+{
+	BUG_ON(bio_data_dir(bio) != READ);
+
+	return bio_integrity_tag(bio, tag_buf, len, 0);
+}
+EXPORT_SYMBOL(bio_integrity_get_tag);
+
+/**
+ * bio_integrity_generate - Generate integrity metadata for a bio
+ * @bio:	bio to generate integrity metadata for
+ *
+ * Description: Generates integrity metadata for a bio by calling the
+ * block device's generation callback function.  The bio must have a
+ * bip attached with enough room to accommodate the generated
+ * integrity metadata.
+ */
+static void bio_integrity_generate(struct bio *bio)
+{
+	struct blk_integrity *bi = bdev_get_integrity(bio->bi_bdev);
+	struct blk_integrity_exchg bix;
+	struct bio_vec *bv;
+	sector_t sector = bio->bi_sector;
+	unsigned int i, sectors, total;
+	void *prot_buf = bio->bi_integrity->bip_buf;
+
+	total = 0;
+	bix.disk_name = bio->bi_bdev->bd_disk->disk_name;
+	bix.sector_size = bi->sector_size;
+
+	bio_for_each_segment(bv, bio, i) {
+		void *kaddr = kmap_atomic(bv->bv_page, KM_USER0);
+		bix.data_buf = kaddr + bv->bv_offset;
+		bix.data_size = bv->bv_len;
+		bix.prot_buf = prot_buf;
+		bix.sector = sector;
+
+		bi->generate_fn(&bix);
+
+		sectors = bv->bv_len / bi->sector_size;
+		sector += sectors;
+		prot_buf += sectors * bi->tuple_size;
+		total += sectors * bi->tuple_size;
+		BUG_ON(total > bio->bi_integrity->bip_size);
+
+		kunmap_atomic(kaddr, KM_USER0);
+	}
+}
+
+/**
+ * bio_integrity_prep - Prepare bio for integrity I/O
+ * @bio:	bio to prepare
+ *
+ * Description: Allocates a buffer for integrity metadata, maps the
+ * pages and attaches them to a bio.  The bio must have data
+ * direction, target device and start sector set priot to calling.  In
+ * the WRITE case, integrity metadata will be generated using the
+ * block device's integrity function.  In the READ case, the buffer
+ * will be prepared for DMA and a suitable end_io handler set up.
+ */
+int bio_integrity_prep(struct bio *bio)
+{
+	struct bio_integrity_payload *bip;
+	struct blk_integrity *bi;
+	struct request_queue *q;
+	void *buf;
+	unsigned long start, end;
+	unsigned int len, nr_pages;
+	unsigned int bytes, offset, i;
+	unsigned int sectors;
+
+	bi = bdev_get_integrity(bio->bi_bdev);
+	q = bdev_get_queue(bio->bi_bdev);
+	BUG_ON(bi == NULL);
+	BUG_ON(bio_integrity(bio));
+
+	sectors = bio_integrity_hw_sectors(bi, bio_sectors(bio));
+
+	/* Allocate kernel buffer for protection data */
+	len = sectors * blk_integrity_tuple_size(bi);
+	buf = kmalloc(len, GFP_NOIO | __GFP_NOFAIL | q->bounce_gfp);
+	if (unlikely(buf == NULL)) {
+		printk(KERN_ERR "could not allocate integrity buffer\n");
+		return -EIO;
+	}
+
+	end = (((unsigned long) buf) + len + PAGE_SIZE - 1) >> PAGE_SHIFT;
+	start = ((unsigned long) buf) >> PAGE_SHIFT;
+	nr_pages = end - start;
+
+	/* Allocate bio integrity payload and integrity vectors */
+	bip = bio_integrity_alloc(bio, GFP_NOIO, nr_pages);
+	if (unlikely(bip == NULL)) {
+		printk(KERN_ERR "could not allocate data integrity bioset\n");
+		kfree(buf);
+		return -EIO;
+	}
+
+	bip->bip_buf = buf;
+	bip->bip_size = len;
+	bip->bip_sector = bio->bi_sector;
+
+	/* Map it */
+	offset = offset_in_page(buf);
+	for (i = 0 ; i < nr_pages ; i++) {
+		int ret;
+		bytes = PAGE_SIZE - offset;
+
+		if (len <= 0)
+			break;
+
+		if (bytes > len)
+			bytes = len;
+
+		ret = bio_integrity_add_page(bio, virt_to_page(buf),
+					     bytes, offset);
+
+		if (ret == 0)
+			return 0;
+
+		if (ret < bytes)
+			break;
+
+		buf += bytes;
+		len -= bytes;
+		offset = 0;
+	}
+
+	/* Install custom I/O completion handler if read verify is enabled */
+	if (bio_data_dir(bio) == READ) {
+		bip->bip_end_io = bio->bi_end_io;
+		bio->bi_end_io = bio_integrity_endio;
+	}
+
+	/* Auto-generate integrity metadata if this is a write */
+	if (bio_data_dir(bio) == WRITE)
+		bio_integrity_generate(bio);
+
+	return 0;
+}
+EXPORT_SYMBOL(bio_integrity_prep);
+
+/**
+ * bio_integrity_verify - Verify integrity metadata for a bio
+ * @bio:	bio to verify
+ *
+ * Description: This function is called to verify the integrity of a
+ * bio.	 The data in the bio io_vec is compared to the integrity
+ * metadata returned by the HBA.
+ */
+static int bio_integrity_verify(struct bio *bio)
+{
+	struct blk_integrity *bi = bdev_get_integrity(bio->bi_bdev);
+	struct blk_integrity_exchg bix;
+	struct bio_vec *bv;
+	sector_t sector = bio->bi_integrity->bip_sector;
+	unsigned int i, sectors, total, ret;
+	void *prot_buf = bio->bi_integrity->bip_buf;
+
+	ret = total = 0;
+	bix.disk_name = bio->bi_bdev->bd_disk->disk_name;
+	bix.sector_size = bi->sector_size;
+
+	bio_for_each_segment(bv, bio, i) {
+		void *kaddr = kmap_atomic(bv->bv_page, KM_USER0);
+		bix.data_buf = kaddr + bv->bv_offset;
+		bix.data_size = bv->bv_len;
+		bix.prot_buf = prot_buf;
+		bix.sector = sector;
+
+		ret = bi->verify_fn(&bix);
+
+		if (ret) {
+			kunmap_atomic(kaddr, KM_USER0);
+			break;
+		}
+
+		sectors = bv->bv_len / bi->sector_size;
+		sector += sectors;
+		prot_buf += sectors * bi->tuple_size;
+		total += sectors * bi->tuple_size;
+		BUG_ON(total > bio->bi_integrity->bip_size);
+
+		kunmap_atomic(kaddr, KM_USER0);
+	}
+
+	return ret;
+}
+
+/**
+ * bio_integrity_verify_fn - Integrity I/O completion worker
+ * @work:	Work struct stored in bio to be verified
+ *
+ * Description: This workqueue function is called to complete a READ
+ * request.  The function verifies the transferred integrity metadata
+ * and then calls the original bio end_io function.
+ */
+static void bio_integrity_verify_fn(struct work_struct *work)
+{
+	struct bio_integrity_payload *bip =
+		container_of(work, struct bio_integrity_payload, bip_work);
+	struct bio *bio = bip->bip_bio;
+	int error = bip->bip_error;
+
+	if (bio_integrity_verify(bio)) {
+		clear_bit(BIO_UPTODATE, &bio->bi_flags);
+		error = -EIO;
+	}
+
+	/* Restore original bio completion handler */
+	bio->bi_end_io = bip->bip_end_io;
+
+	if (bio->bi_end_io)
+		bio->bi_end_io(bio, error);
+}
+
+/**
+ * bio_integrity_endio - Integrity I/O completion function
+ * @bio:	Protected bio
+ * @error:	Pointer to errno
+ *
+ * Description: Completion for integrity I/O
+ *
+ * Normally I/O completion is done in interrupt context.  However,
+ * verifying I/O integrity is a time-consuming task which must be run
+ * in process context.	This function postpones completion
+ * accordingly.
+ */
+void bio_integrity_endio(struct bio *bio, int error)
+{
+	struct bio_integrity_payload *bip = bio->bi_integrity;
+
+	BUG_ON(bip->bip_bio != bio);
+
+	bip->bip_error = error;
+	INIT_WORK(&bip->bip_work, bio_integrity_verify_fn);
+	queue_work(kintegrityd_wq, &bip->bip_work);
+}
+EXPORT_SYMBOL(bio_integrity_endio);
+
+/**
+ * bio_integrity_mark_head - Advance bip_vec skip bytes
+ * @bip:	Integrity vector to advance
+ * @skip:	Number of bytes to advance it
+ */
+void bio_integrity_mark_head(struct bio_integrity_payload *bip,
+			     unsigned int skip)
+{
+	struct bio_vec *iv;
+	unsigned int i;
+
+	bip_for_each_vec(iv, bip, i) {
+		if (skip == 0) {
+			bip->bip_idx = i;
+			return;
+		} else if (skip >= iv->bv_len) {
+			skip -= iv->bv_len;
+		} else { /* skip < iv->bv_len) */
+			iv->bv_offset += skip;
+			iv->bv_len -= skip;
+			bip->bip_idx = i;
+			return;
+		}
+	}
+}
+
+/**
+ * bio_integrity_mark_tail - Truncate bip_vec to be len bytes long
+ * @bip:	Integrity vector to truncate
+ * @len:	New length of integrity vector
+ */
+void bio_integrity_mark_tail(struct bio_integrity_payload *bip,
+			     unsigned int len)
+{
+	struct bio_vec *iv;
+	unsigned int i;
+
+	bip_for_each_vec(iv, bip, i) {
+		if (len == 0) {
+			bip->bip_vcnt = i;
+			return;
+		} else if (len >= iv->bv_len) {
+			len -= iv->bv_len;
+		} else { /* len < iv->bv_len) */
+			iv->bv_len = len;
+			len = 0;
+		}
+	}
+}
+
+/**
+ * bio_integrity_advance - Advance integrity vector
+ * @bio:	bio whose integrity vector to update
+ * @bytes_done:	number of data bytes that have been completed
+ *
+ * Description: This function calculates how many integrity bytes the
+ * number of completed data bytes correspond to and advances the
+ * integrity vector accordingly.
+ */
+void bio_integrity_advance(struct bio *bio, unsigned int bytes_done)
+{
+	struct bio_integrity_payload *bip = bio->bi_integrity;
+	struct blk_integrity *bi = bdev_get_integrity(bio->bi_bdev);
+	unsigned int nr_sectors;
+
+	BUG_ON(bip == NULL);
+	BUG_ON(bi == NULL);
+
+	nr_sectors = bio_integrity_hw_sectors(bi, bytes_done >> 9);
+	bio_integrity_mark_head(bip, nr_sectors * bi->tuple_size);
+}
+EXPORT_SYMBOL(bio_integrity_advance);
+
+/**
+ * bio_integrity_trim - Trim integrity vector
+ * @bio:	bio whose integrity vector to update
+ * @offset:	offset to first data sector
+ * @sectors:	number of data sectors
+ *
+ * Description: Used to trim the integrity vector in a cloned bio.
+ * The ivec will be advanced corresponding to 'offset' data sectors
+ * and the length will be truncated corresponding to 'len' data
+ * sectors.
+ */
+void bio_integrity_trim(struct bio *bio, unsigned int offset,
+			unsigned int sectors)
+{
+	struct bio_integrity_payload *bip = bio->bi_integrity;
+	struct blk_integrity *bi = bdev_get_integrity(bio->bi_bdev);
+	unsigned int nr_sectors;
+
+	BUG_ON(bip == NULL);
+	BUG_ON(bi == NULL);
+	BUG_ON(!bio_flagged(bio, BIO_CLONED));
+
+	nr_sectors = bio_integrity_hw_sectors(bi, sectors);
+	bip->bip_sector = bip->bip_sector + offset;
+	bio_integrity_mark_head(bip, offset * bi->tuple_size);
+	bio_integrity_mark_tail(bip, sectors * bi->tuple_size);
+}
+EXPORT_SYMBOL(bio_integrity_trim);
+
+/**
+ * bio_integrity_split - Split integrity metadata
+ * @bio:	Protected bio
+ * @bp:		Resulting bio_pair
+ * @sectors:	Offset
+ *
+ * Description: Splits an integrity page into a bio_pair.
+ */
+void bio_integrity_split(struct bio *bio, struct bio_pair *bp, int sectors)
+{
+	struct blk_integrity *bi;
+	struct bio_integrity_payload *bip = bio->bi_integrity;
+	unsigned int nr_sectors;
+
+	if (bio_integrity(bio) == 0)
+		return;
+
+	bi = bdev_get_integrity(bio->bi_bdev);
+	BUG_ON(bi == NULL);
+	BUG_ON(bip->bip_vcnt != 1);
+
+	nr_sectors = bio_integrity_hw_sectors(bi, sectors);
+
+	bp->bio1.bi_integrity = &bp->bip1;
+	bp->bio2.bi_integrity = &bp->bip2;
+
+	bp->iv1 = bip->bip_vec[0];
+	bp->iv2 = bip->bip_vec[0];
+
+	bp->bip1.bip_vec = &bp->iv1;
+	bp->bip2.bip_vec = &bp->iv2;
+
+	bp->iv1.bv_len = sectors * bi->tuple_size;
+	bp->iv2.bv_offset += sectors * bi->tuple_size;
+	bp->iv2.bv_len -= sectors * bi->tuple_size;
+
+	bp->bip1.bip_sector = bio->bi_integrity->bip_sector;
+	bp->bip2.bip_sector = bio->bi_integrity->bip_sector + nr_sectors;
+
+	bp->bip1.bip_vcnt = bp->bip2.bip_vcnt = 1;
+	bp->bip1.bip_idx = bp->bip2.bip_idx = 0;
+}
+EXPORT_SYMBOL(bio_integrity_split);
+
+/**
+ * bio_integrity_clone - Callback for cloning bios with integrity metadata
+ * @bio:	New bio
+ * @bio_src:	Original bio
+ * @bs:		bio_set to allocate bip from
+ *
+ * Description:	Called to allocate a bip when cloning a bio
+ */
+int bio_integrity_clone(struct bio *bio, struct bio *bio_src,
+			struct bio_set *bs)
+{
+	struct bio_integrity_payload *bip_src = bio_src->bi_integrity;
+	struct bio_integrity_payload *bip;
+
+	BUG_ON(bip_src == NULL);
+
+	bip = bio_integrity_alloc_bioset(bio, GFP_NOIO, bip_src->bip_vcnt, bs);
+
+	if (bip == NULL)
+		return -EIO;
+
+	memcpy(bip->bip_vec, bip_src->bip_vec,
+	       bip_src->bip_vcnt * sizeof(struct bio_vec));
+
+	bip->bip_sector = bip_src->bip_sector;
+	bip->bip_vcnt = bip_src->bip_vcnt;
+	bip->bip_idx = bip_src->bip_idx;
+
+	return 0;
+}
+EXPORT_SYMBOL(bio_integrity_clone);
+
+int bioset_integrity_create(struct bio_set *bs, int pool_size)
+{
+	bs->bio_integrity_pool = mempool_create_slab_pool(pool_size,
+							  bio_integrity_slab);
+	if (!bs->bio_integrity_pool)
+		return -1;
+
+	return 0;
+}
+EXPORT_SYMBOL(bioset_integrity_create);
+
+void bioset_integrity_free(struct bio_set *bs)
+{
+	if (bs->bio_integrity_pool)
+		mempool_destroy(bs->bio_integrity_pool);
+}
+EXPORT_SYMBOL(bioset_integrity_free);
+
+void __init bio_integrity_init_slab(void)
+{
+	bio_integrity_slab = KMEM_CACHE(bio_integrity_payload,
+					SLAB_HWCACHE_ALIGN|SLAB_PANIC);
+}
+EXPORT_SYMBOL(bio_integrity_init_slab);
+
+static int __init integrity_init(void)
+{
+	kintegrityd_wq = create_workqueue("kintegrityd");
+
+	if (!kintegrityd_wq)
+		panic("Failed to create kintegrityd\n");
+
+	return 0;
+}
+subsys_initcall(integrity_init);
diff --git a/fs/bio.c b/fs/bio.c
index 78562574cb5..88322b066ac 100644
--- a/fs/bio.c
+++ b/fs/bio.c
@@ -28,25 +28,10 @@
 #include <linux/blktrace_api.h>
 #include <scsi/sg.h>		/* for struct sg_iovec */
 
-#define BIO_POOL_SIZE 2
-
 static struct kmem_cache *bio_slab __read_mostly;
 
-#define BIOVEC_NR_POOLS 6
-
-/*
- * a small number of entries is fine, not going to be performance critical.
- * basically we just need to survive
- */
-#define BIO_SPLIT_ENTRIES 2
 mempool_t *bio_split_pool __read_mostly;
 
-struct biovec_slab {
-	int nr_vecs;
-	char *name; 
-	struct kmem_cache *slab;
-};
-
 /*
  * if you change this list, also change bvec_alloc or things will
  * break badly! cannot be bigger than what you can fit into an
@@ -60,23 +45,17 @@ static struct biovec_slab bvec_slabs[BIOVEC_NR_POOLS] __read_mostly = {
 #undef BV
 
 /*
- * bio_set is used to allow other portions of the IO system to
- * allocate their own private memory pools for bio and iovec structures.
- * These memory pools in turn all allocate from the bio_slab
- * and the bvec_slabs[].
- */
-struct bio_set {
-	mempool_t *bio_pool;
-	mempool_t *bvec_pools[BIOVEC_NR_POOLS];
-};
-
-/*
  * fs_bio_set is the bio_set containing bio and iovec memory pools used by
  * IO code that does not need private memory pools.
  */
-static struct bio_set *fs_bio_set;
+struct bio_set *fs_bio_set;
+
+unsigned int bvec_nr_vecs(unsigned short idx)
+{
+	return bvec_slabs[idx].nr_vecs;
+}
 
-static inline struct bio_vec *bvec_alloc_bs(gfp_t gfp_mask, int nr, unsigned long *idx, struct bio_set *bs)
+struct bio_vec *bvec_alloc_bs(gfp_t gfp_mask, int nr, unsigned long *idx, struct bio_set *bs)
 {
 	struct bio_vec *bvl;
 
@@ -117,6 +96,9 @@ void bio_free(struct bio *bio, struct bio_set *bio_set)
 		mempool_free(bio->bi_io_vec, bio_set->bvec_pools[pool_idx]);
 	}
 
+	if (bio_integrity(bio))
+		bio_integrity_free(bio, bio_set);
+
 	mempool_free(bio, bio_set->bio_pool);
 }
 
@@ -275,9 +257,19 @@ struct bio *bio_clone(struct bio *bio, gfp_t gfp_mask)
 {
 	struct bio *b = bio_alloc_bioset(gfp_mask, bio->bi_max_vecs, fs_bio_set);
 
-	if (b) {
-		b->bi_destructor = bio_fs_destructor;
-		__bio_clone(b, bio);
+	if (!b)
+		return NULL;
+
+	b->bi_destructor = bio_fs_destructor;
+	__bio_clone(b, bio);
+
+	if (bio_integrity(bio)) {
+		int ret;
+
+		ret = bio_integrity_clone(b, bio, fs_bio_set);
+
+		if (ret < 0)
+			return NULL;
 	}
 
 	return b;
@@ -333,10 +325,19 @@ static int __bio_add_page(struct request_queue *q, struct bio *bio, struct page
 		if (page == prev->bv_page &&
 		    offset == prev->bv_offset + prev->bv_len) {
 			prev->bv_len += len;
-			if (q->merge_bvec_fn &&
-			    q->merge_bvec_fn(q, bio, prev) < len) {
-				prev->bv_len -= len;
-				return 0;
+
+			if (q->merge_bvec_fn) {
+				struct bvec_merge_data bvm = {
+					.bi_bdev = bio->bi_bdev,
+					.bi_sector = bio->bi_sector,
+					.bi_size = bio->bi_size,
+					.bi_rw = bio->bi_rw,
+				};
+
+				if (q->merge_bvec_fn(q, &bvm, prev) < len) {
+					prev->bv_len -= len;
+					return 0;
+				}
 			}
 
 			goto done;
@@ -377,11 +378,18 @@ static int __bio_add_page(struct request_queue *q, struct bio *bio, struct page
 	 * queue to get further control
 	 */
 	if (q->merge_bvec_fn) {
+		struct bvec_merge_data bvm = {
+			.bi_bdev = bio->bi_bdev,
+			.bi_sector = bio->bi_sector,
+			.bi_size = bio->bi_size,
+			.bi_rw = bio->bi_rw,
+		};
+
 		/*
 		 * merge_bvec_fn() returns number of bytes it can accept
 		 * at this offset
 		 */
-		if (q->merge_bvec_fn(q, bio, bvec) < len) {
+		if (q->merge_bvec_fn(q, &bvm, bvec) < len) {
 			bvec->bv_page = NULL;
 			bvec->bv_len = 0;
 			bvec->bv_offset = 0;
@@ -1249,6 +1257,9 @@ struct bio_pair *bio_split(struct bio *bi, mempool_t *pool, int first_sectors)
 	bp->bio1.bi_private = bi;
 	bp->bio2.bi_private = pool;
 
+	if (bio_integrity(bi))
+		bio_integrity_split(bi, bp, first_sectors);
+
 	return bp;
 }
 
@@ -1290,6 +1301,7 @@ void bioset_free(struct bio_set *bs)
 	if (bs->bio_pool)
 		mempool_destroy(bs->bio_pool);
 
+	bioset_integrity_free(bs);
 	biovec_free_pools(bs);
 
 	kfree(bs);
@@ -1306,6 +1318,9 @@ struct bio_set *bioset_create(int bio_pool_size, int bvec_pool_size)
 	if (!bs->bio_pool)
 		goto bad;
 
+	if (bioset_integrity_create(bs, bio_pool_size))
+		goto bad;
+
 	if (!biovec_create_pools(bs, bvec_pool_size))
 		return bs;
 
@@ -1332,6 +1347,7 @@ static int __init init_bio(void)
 {
 	bio_slab = KMEM_CACHE(bio, SLAB_HWCACHE_ALIGN|SLAB_PANIC);
 
+	bio_integrity_init_slab();
 	biovec_init_slabs();
 
 	fs_bio_set = bioset_create(BIO_POOL_SIZE, 2);
diff --git a/fs/buffer.c b/fs/buffer.c
index 0f51c0f7c26..d48caee12e2 100644
--- a/fs/buffer.c
+++ b/fs/buffer.c
@@ -1464,7 +1464,7 @@ static void invalidate_bh_lru(void *arg)
 	
 void invalidate_bh_lrus(void)
 {
-	on_each_cpu(invalidate_bh_lru, NULL, 1, 1);
+	on_each_cpu(invalidate_bh_lru, NULL, 1);
 }
 EXPORT_SYMBOL_GPL(invalidate_bh_lrus);
 
@@ -1691,11 +1691,13 @@ static int __block_write_full_page(struct inode *inode, struct page *page,
 			 */
 			clear_buffer_dirty(bh);
 			set_buffer_uptodate(bh);
-		} else if (!buffer_mapped(bh) && buffer_dirty(bh)) {
+		} else if ((!buffer_mapped(bh) || buffer_delay(bh)) &&
+			   buffer_dirty(bh)) {
 			WARN_ON(bh->b_size != blocksize);
 			err = get_block(inode, block, bh, 1);
 			if (err)
 				goto recover;
+			clear_buffer_delay(bh);
 			if (buffer_new(bh)) {
 				/* blockdev mappings never come here */
 				clear_buffer_new(bh);
@@ -1774,7 +1776,8 @@ recover:
 	bh = head;
 	/* Recovery: lock and submit the mapped buffers */
 	do {
-		if (buffer_mapped(bh) && buffer_dirty(bh)) {
+		if (buffer_mapped(bh) && buffer_dirty(bh) &&
+		    !buffer_delay(bh)) {
 			lock_buffer(bh);
 			mark_buffer_async_write(bh);
 		} else {
@@ -2061,6 +2064,7 @@ int generic_write_end(struct file *file, struct address_space *mapping,
 			struct page *page, void *fsdata)
 {
 	struct inode *inode = mapping->host;
+	int i_size_changed = 0;
 
 	copied = block_write_end(file, mapping, pos, len, copied, page, fsdata);
 
@@ -2073,12 +2077,21 @@ int generic_write_end(struct file *file, struct address_space *mapping,
 	 */
 	if (pos+copied > inode->i_size) {
 		i_size_write(inode, pos+copied);
-		mark_inode_dirty(inode);
+		i_size_changed = 1;
 	}
 
 	unlock_page(page);
 	page_cache_release(page);
 
+	/*
+	 * Don't mark the inode dirty under page lock. First, it unnecessarily
+	 * makes the holding time of page lock longer. Second, it forces lock
+	 * ordering of page lock and transaction start for journaling
+	 * filesystems.
+	 */
+	if (i_size_changed)
+		mark_inode_dirty(inode);
+
 	return copied;
 }
 EXPORT_SYMBOL(generic_write_end);
diff --git a/fs/char_dev.c b/fs/char_dev.c
index 68e510b8845..3cb7cda3d78 100644
--- a/fs/char_dev.c
+++ b/fs/char_dev.c
@@ -373,6 +373,8 @@ static int chrdev_open(struct inode *inode, struct file *filp)
 			return -ENXIO;
 		new = container_of(kobj, struct cdev, kobj);
 		spin_lock(&cdev_lock);
+		/* Check i_cdev again in case somebody beat us to it while
+		   we dropped the lock. */
 		p = inode->i_cdev;
 		if (!p) {
 			inode->i_cdev = p = new;
@@ -392,11 +394,8 @@ static int chrdev_open(struct inode *inode, struct file *filp)
 		cdev_put(p);
 		return -ENXIO;
 	}
-	if (filp->f_op->open) {
-		lock_kernel();
+	if (filp->f_op->open)
 		ret = filp->f_op->open(inode,filp);
-		unlock_kernel();
-	}
 	if (ret)
 		cdev_put(p);
 	return ret;
diff --git a/fs/cifs/cifsacl.c b/fs/cifs/cifsacl.c
index 34902cff540..0e9fc2ba90e 100644
--- a/fs/cifs/cifsacl.c
+++ b/fs/cifs/cifsacl.c
@@ -34,11 +34,11 @@
 static struct cifs_wksid wksidarr[NUM_WK_SIDS] = {
 	{{1, 0, {0, 0, 0, 0, 0, 0}, {0, 0, 0, 0, 0} }, "null user"},
 	{{1, 1, {0, 0, 0, 0, 0, 1}, {0, 0, 0, 0, 0} }, "nobody"},
-	{{1, 1, {0, 0, 0, 0, 0, 5}, {cpu_to_le32(11), 0, 0, 0, 0} }, "net-users"},
-	{{1, 1, {0, 0, 0, 0, 0, 5}, {cpu_to_le32(18), 0, 0, 0, 0} }, "sys"},
-	{{1, 2, {0, 0, 0, 0, 0, 5}, {cpu_to_le32(32), cpu_to_le32(544), 0, 0, 0} }, "root"},
-	{{1, 2, {0, 0, 0, 0, 0, 5}, {cpu_to_le32(32), cpu_to_le32(545), 0, 0, 0} }, "users"},
-	{{1, 2, {0, 0, 0, 0, 0, 5}, {cpu_to_le32(32), cpu_to_le32(546), 0, 0, 0} }, "guest"} }
+	{{1, 1, {0, 0, 0, 0, 0, 5}, {__constant_cpu_to_le32(11), 0, 0, 0, 0} }, "net-users"},
+	{{1, 1, {0, 0, 0, 0, 0, 5}, {__constant_cpu_to_le32(18), 0, 0, 0, 0} }, "sys"},
+	{{1, 2, {0, 0, 0, 0, 0, 5}, {__constant_cpu_to_le32(32), __constant_cpu_to_le32(544), 0, 0, 0} }, "root"},
+	{{1, 2, {0, 0, 0, 0, 0, 5}, {__constant_cpu_to_le32(32), __constant_cpu_to_le32(545), 0, 0, 0} }, "users"},
+	{{1, 2, {0, 0, 0, 0, 0, 5}, {__constant_cpu_to_le32(32), __constant_cpu_to_le32(546), 0, 0, 0} }, "guest"} }
 ;
 
 
diff --git a/fs/cifs/cifsfs.c b/fs/cifs/cifsfs.c
index 86b4d5f405a..22857c639df 100644
--- a/fs/cifs/cifsfs.c
+++ b/fs/cifs/cifsfs.c
@@ -612,7 +612,7 @@ static loff_t cifs_llseek(struct file *file, loff_t offset, int origin)
 		if (retval < 0)
 			return (loff_t)retval;
 	}
-	return remote_llseek(file, offset, origin);
+	return generic_file_llseek_unlocked(file, offset, origin);
 }
 
 struct file_system_type cifs_fs_type = {
diff --git a/fs/cifs/inode.c b/fs/cifs/inode.c
index 722be543cee..2e904bd111c 100644
--- a/fs/cifs/inode.c
+++ b/fs/cifs/inode.c
@@ -219,15 +219,15 @@ int cifs_get_inode_info_unix(struct inode **pinode,
 	rc = CIFSSMBUnixQPathInfo(xid, pTcon, full_path, &find_data,
 				  cifs_sb->local_nls, cifs_sb->mnt_cifs_flags &
 					CIFS_MOUNT_MAP_SPECIAL_CHR);
-	if (rc) {
-		if (rc == -EREMOTE && !is_dfs_referral) {
-			is_dfs_referral = true;
-			cFYI(DBG2, ("DFS ref"));
-			/* for DFS, server does not give us real inode data */
-			fill_fake_finddataunix(&find_data, sb);
-			rc = 0;
-		}
-	}
+	if (rc == -EREMOTE && !is_dfs_referral) {
+		is_dfs_referral = true;
+		cFYI(DBG2, ("DFS ref"));
+		/* for DFS, server does not give us real inode data */
+		fill_fake_finddataunix(&find_data, sb);
+		rc = 0;
+	} else if (rc)
+		goto cgiiu_exit;
+
 	num_of_bytes = le64_to_cpu(find_data.NumOfBytes);
 	end_of_file = le64_to_cpu(find_data.EndOfFile);
 
@@ -236,7 +236,7 @@ int cifs_get_inode_info_unix(struct inode **pinode,
 		*pinode = new_inode(sb);
 		if (*pinode == NULL) {
 			rc = -ENOMEM;
-		goto cgiiu_exit;
+			goto cgiiu_exit;
 		}
 		/* Is an i_ino of zero legal? */
 		/* note ino incremented to unique num in new_inode */
diff --git a/fs/compat_ioctl.c b/fs/compat_ioctl.c
index 05ec7eef869..ddefb8851a9 100644
--- a/fs/compat_ioctl.c
+++ b/fs/compat_ioctl.c
@@ -68,9 +68,11 @@
 #include <linux/capi.h>
 #include <linux/gigaset_dev.h>
 
+#ifdef CONFIG_BLOCK
 #include <scsi/scsi.h>
 #include <scsi/scsi_ioctl.h>
 #include <scsi/sg.h>
+#endif
 
 #include <asm/uaccess.h>
 #include <linux/ethtool.h>
@@ -1965,6 +1967,7 @@ COMPATIBLE_IOCTL(GIO_UNISCRNMAP)
 COMPATIBLE_IOCTL(PIO_UNISCRNMAP)
 COMPATIBLE_IOCTL(PIO_FONTRESET)
 COMPATIBLE_IOCTL(PIO_UNIMAPCLR)
+#ifdef CONFIG_BLOCK
 /* Big S */
 COMPATIBLE_IOCTL(SCSI_IOCTL_GET_IDLUN)
 COMPATIBLE_IOCTL(SCSI_IOCTL_DOORLOCK)
@@ -1974,6 +1977,7 @@ COMPATIBLE_IOCTL(SCSI_IOCTL_GET_BUS_NUMBER)
 COMPATIBLE_IOCTL(SCSI_IOCTL_SEND_COMMAND)
 COMPATIBLE_IOCTL(SCSI_IOCTL_PROBE_HOST)
 COMPATIBLE_IOCTL(SCSI_IOCTL_GET_PCI)
+#endif
 /* Big T */
 COMPATIBLE_IOCTL(TUNSETNOCSUM)
 COMPATIBLE_IOCTL(TUNSETDEBUG)
@@ -2044,6 +2048,7 @@ COMPATIBLE_IOCTL(SIOCGIFVLAN)
 COMPATIBLE_IOCTL(SIOCSIFVLAN)
 COMPATIBLE_IOCTL(SIOCBRADDBR)
 COMPATIBLE_IOCTL(SIOCBRDELBR)
+#ifdef CONFIG_BLOCK
 /* SG stuff */
 COMPATIBLE_IOCTL(SG_SET_TIMEOUT)
 COMPATIBLE_IOCTL(SG_GET_TIMEOUT)
@@ -2068,6 +2073,7 @@ COMPATIBLE_IOCTL(SG_SCSI_RESET)
 COMPATIBLE_IOCTL(SG_GET_REQUEST_TABLE)
 COMPATIBLE_IOCTL(SG_SET_KEEP_ORPHAN)
 COMPATIBLE_IOCTL(SG_GET_KEEP_ORPHAN)
+#endif
 /* PPP stuff */
 COMPATIBLE_IOCTL(PPPIOCGFLAGS)
 COMPATIBLE_IOCTL(PPPIOCSFLAGS)
diff --git a/fs/configfs/configfs_internal.h b/fs/configfs/configfs_internal.h
index cca98609aa7..da015c12e3e 100644
--- a/fs/configfs/configfs_internal.h
+++ b/fs/configfs/configfs_internal.h
@@ -26,6 +26,7 @@
 
 #include <linux/slab.h>
 #include <linux/list.h>
+#include <linux/spinlock.h>
 
 struct configfs_dirent {
 	atomic_t		s_count;
@@ -47,8 +48,11 @@ struct configfs_dirent {
 #define CONFIGFS_USET_DIR	0x0040
 #define CONFIGFS_USET_DEFAULT	0x0080
 #define CONFIGFS_USET_DROPPING	0x0100
+#define CONFIGFS_USET_IN_MKDIR	0x0200
 #define CONFIGFS_NOT_PINNED	(CONFIGFS_ITEM_ATTR)
 
+extern spinlock_t configfs_dirent_lock;
+
 extern struct vfsmount * configfs_mount;
 extern struct kmem_cache *configfs_dir_cachep;
 
diff --git a/fs/configfs/dir.c b/fs/configfs/dir.c
index a48dc7dd876..0e64312a084 100644
--- a/fs/configfs/dir.c
+++ b/fs/configfs/dir.c
@@ -30,11 +30,25 @@
 #include <linux/mount.h>
 #include <linux/module.h>
 #include <linux/slab.h>
+#include <linux/err.h>
 
 #include <linux/configfs.h>
 #include "configfs_internal.h"
 
 DECLARE_RWSEM(configfs_rename_sem);
+/*
+ * Protects mutations of configfs_dirent linkage together with proper i_mutex
+ * Also protects mutations of symlinks linkage to target configfs_dirent
+ * Mutators of configfs_dirent linkage must *both* have the proper inode locked
+ * and configfs_dirent_lock locked, in that order.
+ * This allows one to safely traverse configfs_dirent trees and symlinks without
+ * having to lock inodes.
+ *
+ * Protects setting of CONFIGFS_USET_DROPPING: checking the flag
+ * unlocked is not reliable unless in detach_groups() called from
+ * rmdir()/unregister() and from configfs_attach_group()
+ */
+DEFINE_SPINLOCK(configfs_dirent_lock);
 
 static void configfs_d_iput(struct dentry * dentry,
 			    struct inode * inode)
@@ -74,13 +88,20 @@ static struct configfs_dirent *configfs_new_dirent(struct configfs_dirent * pare
 
 	sd = kmem_cache_zalloc(configfs_dir_cachep, GFP_KERNEL);
 	if (!sd)
-		return NULL;
+		return ERR_PTR(-ENOMEM);
 
 	atomic_set(&sd->s_count, 1);
 	INIT_LIST_HEAD(&sd->s_links);
 	INIT_LIST_HEAD(&sd->s_children);
-	list_add(&sd->s_sibling, &parent_sd->s_children);
 	sd->s_element = element;
+	spin_lock(&configfs_dirent_lock);
+	if (parent_sd->s_type & CONFIGFS_USET_DROPPING) {
+		spin_unlock(&configfs_dirent_lock);
+		kmem_cache_free(configfs_dir_cachep, sd);
+		return ERR_PTR(-ENOENT);
+	}
+	list_add(&sd->s_sibling, &parent_sd->s_children);
+	spin_unlock(&configfs_dirent_lock);
 
 	return sd;
 }
@@ -118,8 +139,8 @@ int configfs_make_dirent(struct configfs_dirent * parent_sd,
 	struct configfs_dirent * sd;
 
 	sd = configfs_new_dirent(parent_sd, element);
-	if (!sd)
-		return -ENOMEM;
+	if (IS_ERR(sd))
+		return PTR_ERR(sd);
 
 	sd->s_mode = mode;
 	sd->s_type = type;
@@ -173,7 +194,9 @@ static int create_dir(struct config_item * k, struct dentry * p,
 		} else {
 			struct configfs_dirent *sd = d->d_fsdata;
 			if (sd) {
+				spin_lock(&configfs_dirent_lock);
 				list_del_init(&sd->s_sibling);
+				spin_unlock(&configfs_dirent_lock);
 				configfs_put(sd);
 			}
 		}
@@ -224,7 +247,9 @@ int configfs_create_link(struct configfs_symlink *sl,
 		else {
 			struct configfs_dirent *sd = dentry->d_fsdata;
 			if (sd) {
+				spin_lock(&configfs_dirent_lock);
 				list_del_init(&sd->s_sibling);
+				spin_unlock(&configfs_dirent_lock);
 				configfs_put(sd);
 			}
 		}
@@ -238,7 +263,9 @@ static void remove_dir(struct dentry * d)
 	struct configfs_dirent * sd;
 
 	sd = d->d_fsdata;
+	spin_lock(&configfs_dirent_lock);
 	list_del_init(&sd->s_sibling);
+	spin_unlock(&configfs_dirent_lock);
 	configfs_put(sd);
 	if (d->d_inode)
 		simple_rmdir(parent->d_inode,d);
@@ -331,13 +358,13 @@ static struct dentry * configfs_lookup(struct inode *dir,
 
 /*
  * Only subdirectories count here.  Files (CONFIGFS_NOT_PINNED) are
- * attributes and are removed by rmdir().  We recurse, taking i_mutex
- * on all children that are candidates for default detach.  If the
- * result is clean, then configfs_detach_group() will handle dropping
- * i_mutex.  If there is an error, the caller will clean up the i_mutex
- * holders via configfs_detach_rollback().
+ * attributes and are removed by rmdir().  We recurse, setting
+ * CONFIGFS_USET_DROPPING on all children that are candidates for
+ * default detach.
+ * If there is an error, the caller will reset the flags via
+ * configfs_detach_rollback().
  */
-static int configfs_detach_prep(struct dentry *dentry)
+static int configfs_detach_prep(struct dentry *dentry, struct mutex **wait_mutex)
 {
 	struct configfs_dirent *parent_sd = dentry->d_fsdata;
 	struct configfs_dirent *sd;
@@ -352,15 +379,20 @@ static int configfs_detach_prep(struct dentry *dentry)
 		if (sd->s_type & CONFIGFS_NOT_PINNED)
 			continue;
 		if (sd->s_type & CONFIGFS_USET_DEFAULT) {
-			mutex_lock(&sd->s_dentry->d_inode->i_mutex);
-			/* Mark that we've taken i_mutex */
+			/* Abort if racing with mkdir() */
+			if (sd->s_type & CONFIGFS_USET_IN_MKDIR) {
+				if (wait_mutex)
+					*wait_mutex = &sd->s_dentry->d_inode->i_mutex;
+				return -EAGAIN;
+			}
+			/* Mark that we're trying to drop the group */
 			sd->s_type |= CONFIGFS_USET_DROPPING;
 
 			/*
 			 * Yup, recursive.  If there's a problem, blame
 			 * deep nesting of default_groups
 			 */
-			ret = configfs_detach_prep(sd->s_dentry);
+			ret = configfs_detach_prep(sd->s_dentry, wait_mutex);
 			if (!ret)
 				continue;
 		} else
@@ -374,7 +406,7 @@ out:
 }
 
 /*
- * Walk the tree, dropping i_mutex wherever CONFIGFS_USET_DROPPING is
+ * Walk the tree, resetting CONFIGFS_USET_DROPPING wherever it was
  * set.
  */
 static void configfs_detach_rollback(struct dentry *dentry)
@@ -385,11 +417,7 @@ static void configfs_detach_rollback(struct dentry *dentry)
 	list_for_each_entry(sd, &parent_sd->s_children, s_sibling) {
 		if (sd->s_type & CONFIGFS_USET_DEFAULT) {
 			configfs_detach_rollback(sd->s_dentry);
-
-			if (sd->s_type & CONFIGFS_USET_DROPPING) {
-				sd->s_type &= ~CONFIGFS_USET_DROPPING;
-				mutex_unlock(&sd->s_dentry->d_inode->i_mutex);
-			}
+			sd->s_type &= ~CONFIGFS_USET_DROPPING;
 		}
 	}
 }
@@ -410,7 +438,9 @@ static void detach_attrs(struct config_item * item)
 	list_for_each_entry_safe(sd, tmp, &parent_sd->s_children, s_sibling) {
 		if (!sd->s_element || !(sd->s_type & CONFIGFS_NOT_PINNED))
 			continue;
+		spin_lock(&configfs_dirent_lock);
 		list_del_init(&sd->s_sibling);
+		spin_unlock(&configfs_dirent_lock);
 		configfs_drop_dentry(sd, dentry);
 		configfs_put(sd);
 	}
@@ -466,16 +496,12 @@ static void detach_groups(struct config_group *group)
 
 		child = sd->s_dentry;
 
+		mutex_lock(&child->d_inode->i_mutex);
+
 		configfs_detach_group(sd->s_element);
 		child->d_inode->i_flags |= S_DEAD;
 
-		/*
-		 * From rmdir/unregister, a configfs_detach_prep() pass
-		 * has taken our i_mutex for us.  Drop it.
-		 * From mkdir/register cleanup, there is no sem held.
-		 */
-		if (sd->s_type & CONFIGFS_USET_DROPPING)
-			mutex_unlock(&child->d_inode->i_mutex);
+		mutex_unlock(&child->d_inode->i_mutex);
 
 		d_delete(child);
 		dput(child);
@@ -1047,25 +1073,24 @@ static int configfs_mkdir(struct inode *dir, struct dentry *dentry, int mode)
 	group = NULL;
 	item = NULL;
 	if (type->ct_group_ops->make_group) {
-		group = type->ct_group_ops->make_group(to_config_group(parent_item), name);
-		if (group) {
+		ret = type->ct_group_ops->make_group(to_config_group(parent_item), name, &group);
+		if (!ret) {
 			link_group(to_config_group(parent_item), group);
 			item = &group->cg_item;
 		}
 	} else {
-		item = type->ct_group_ops->make_item(to_config_group(parent_item), name);
-		if (item)
+		ret = type->ct_group_ops->make_item(to_config_group(parent_item), name, &item);
+		if (!ret)
 			link_obj(parent_item, item);
 	}
 	mutex_unlock(&subsys->su_mutex);
 
 	kfree(name);
-	if (!item) {
+	if (ret) {
 		/*
-		 * If item == NULL, then link_obj() was never called.
+		 * If ret != 0, then link_obj() was never called.
 		 * There are no extra references to clean up.
 		 */
-		ret = -ENOMEM;
 		goto out_put;
 	}
 
@@ -1093,11 +1118,26 @@ static int configfs_mkdir(struct inode *dir, struct dentry *dentry, int mode)
 	 */
 	module_got = 1;
 
+	/*
+	 * Make racing rmdir() fail if it did not tag parent with
+	 * CONFIGFS_USET_DROPPING
+	 * Note: if CONFIGFS_USET_DROPPING is already set, attach_group() will
+	 * fail and let rmdir() terminate correctly
+	 */
+	spin_lock(&configfs_dirent_lock);
+	/* This will make configfs_detach_prep() fail */
+	sd->s_type |= CONFIGFS_USET_IN_MKDIR;
+	spin_unlock(&configfs_dirent_lock);
+
 	if (group)
 		ret = configfs_attach_group(parent_item, item, dentry);
 	else
 		ret = configfs_attach_item(parent_item, item, dentry);
 
+	spin_lock(&configfs_dirent_lock);
+	sd->s_type &= ~CONFIGFS_USET_IN_MKDIR;
+	spin_unlock(&configfs_dirent_lock);
+
 out_unlink:
 	if (ret) {
 		/* Tear down everything we built up */
@@ -1161,12 +1201,27 @@ static int configfs_rmdir(struct inode *dir, struct dentry *dentry)
 		return -EINVAL;
 	}
 
-	ret = configfs_detach_prep(dentry);
-	if (ret) {
-		configfs_detach_rollback(dentry);
-		config_item_put(parent_item);
-		return ret;
-	}
+	spin_lock(&configfs_dirent_lock);
+	do {
+		struct mutex *wait_mutex;
+
+		ret = configfs_detach_prep(dentry, &wait_mutex);
+		if (ret) {
+			configfs_detach_rollback(dentry);
+			spin_unlock(&configfs_dirent_lock);
+			if (ret != -EAGAIN) {
+				config_item_put(parent_item);
+				return ret;
+			}
+
+			/* Wait until the racing operation terminates */
+			mutex_lock(wait_mutex);
+			mutex_unlock(wait_mutex);
+
+			spin_lock(&configfs_dirent_lock);
+		}
+	} while (ret == -EAGAIN);
+	spin_unlock(&configfs_dirent_lock);
 
 	/* Get a working ref for the duration of this function */
 	item = configfs_get_config_item(dentry);
@@ -1258,7 +1313,7 @@ static int configfs_dir_open(struct inode *inode, struct file *file)
 	file->private_data = configfs_new_dirent(parent_sd, NULL);
 	mutex_unlock(&dentry->d_inode->i_mutex);
 
-	return file->private_data ? 0 : -ENOMEM;
+	return IS_ERR(file->private_data) ? PTR_ERR(file->private_data) : 0;
 
 }
 
@@ -1268,7 +1323,9 @@ static int configfs_dir_close(struct inode *inode, struct file *file)
 	struct configfs_dirent * cursor = file->private_data;
 
 	mutex_lock(&dentry->d_inode->i_mutex);
+	spin_lock(&configfs_dirent_lock);
 	list_del_init(&cursor->s_sibling);
+	spin_unlock(&configfs_dirent_lock);
 	mutex_unlock(&dentry->d_inode->i_mutex);
 
 	release_configfs_dirent(cursor);
@@ -1308,7 +1365,9 @@ static int configfs_readdir(struct file * filp, void * dirent, filldir_t filldir
 			/* fallthrough */
 		default:
 			if (filp->f_pos == 2) {
+				spin_lock(&configfs_dirent_lock);
 				list_move(q, &parent_sd->s_children);
+				spin_unlock(&configfs_dirent_lock);
 			}
 			for (p=q->next; p!= &parent_sd->s_children; p=p->next) {
 				struct configfs_dirent *next;
@@ -1331,7 +1390,9 @@ static int configfs_readdir(struct file * filp, void * dirent, filldir_t filldir
 						 dt_type(next)) < 0)
 					return 0;
 
+				spin_lock(&configfs_dirent_lock);
 				list_move(q, p);
+				spin_unlock(&configfs_dirent_lock);
 				p = q;
 				filp->f_pos++;
 			}
@@ -1362,6 +1423,7 @@ static loff_t configfs_dir_lseek(struct file * file, loff_t offset, int origin)
 			struct list_head *p;
 			loff_t n = file->f_pos - 2;
 
+			spin_lock(&configfs_dirent_lock);
 			list_del(&cursor->s_sibling);
 			p = sd->s_children.next;
 			while (n && p != &sd->s_children) {
@@ -1373,6 +1435,7 @@ static loff_t configfs_dir_lseek(struct file * file, loff_t offset, int origin)
 				p = p->next;
 			}
 			list_add_tail(&cursor->s_sibling, p);
+			spin_unlock(&configfs_dirent_lock);
 		}
 	}
 	mutex_unlock(&dentry->d_inode->i_mutex);
@@ -1448,9 +1511,11 @@ void configfs_unregister_subsystem(struct configfs_subsystem *subsys)
 	mutex_lock_nested(&configfs_sb->s_root->d_inode->i_mutex,
 			  I_MUTEX_PARENT);
 	mutex_lock_nested(&dentry->d_inode->i_mutex, I_MUTEX_CHILD);
-	if (configfs_detach_prep(dentry)) {
+	spin_lock(&configfs_dirent_lock);
+	if (configfs_detach_prep(dentry, NULL)) {
 		printk(KERN_ERR "configfs: Tried to unregister non-empty subsystem!\n");
 	}
+	spin_unlock(&configfs_dirent_lock);
 	configfs_detach_group(&group->cg_item);
 	dentry->d_inode->i_flags |= S_DEAD;
 	mutex_unlock(&dentry->d_inode->i_mutex);
diff --git a/fs/configfs/inode.c b/fs/configfs/inode.c
index b9a1d810346..4803ccc9448 100644
--- a/fs/configfs/inode.c
+++ b/fs/configfs/inode.c
@@ -247,7 +247,9 @@ void configfs_hash_and_remove(struct dentry * dir, const char * name)
 		if (!sd->s_element)
 			continue;
 		if (!strcmp(configfs_get_name(sd), name)) {
+			spin_lock(&configfs_dirent_lock);
 			list_del_init(&sd->s_sibling);
+			spin_unlock(&configfs_dirent_lock);
 			configfs_drop_dentry(sd, dir);
 			configfs_put(sd);
 			break;
diff --git a/fs/configfs/symlink.c b/fs/configfs/symlink.c
index 2a731ef5f30..0004d18c40a 100644
--- a/fs/configfs/symlink.c
+++ b/fs/configfs/symlink.c
@@ -77,12 +77,15 @@ static int create_link(struct config_item *parent_item,
 	sl = kmalloc(sizeof(struct configfs_symlink), GFP_KERNEL);
 	if (sl) {
 		sl->sl_target = config_item_get(item);
-		/* FIXME: needs a lock, I'd bet */
+		spin_lock(&configfs_dirent_lock);
 		list_add(&sl->sl_list, &target_sd->s_links);
+		spin_unlock(&configfs_dirent_lock);
 		ret = configfs_create_link(sl, parent_item->ci_dentry,
 					   dentry);
 		if (ret) {
+			spin_lock(&configfs_dirent_lock);
 			list_del_init(&sl->sl_list);
+			spin_unlock(&configfs_dirent_lock);
 			config_item_put(item);
 			kfree(sl);
 		}
@@ -137,8 +140,12 @@ int configfs_symlink(struct inode *dir, struct dentry *dentry, const char *symna
 		goto out_put;
 
 	ret = type->ct_item_ops->allow_link(parent_item, target_item);
-	if (!ret)
+	if (!ret) {
 		ret = create_link(parent_item, target_item, dentry);
+		if (ret && type->ct_item_ops->drop_link)
+			type->ct_item_ops->drop_link(parent_item,
+						     target_item);
+	}
 
 	config_item_put(target_item);
 	path_put(&nd.path);
@@ -169,7 +176,9 @@ int configfs_unlink(struct inode *dir, struct dentry *dentry)
 	parent_item = configfs_get_config_item(dentry->d_parent);
 	type = parent_item->ci_type;
 
+	spin_lock(&configfs_dirent_lock);
 	list_del_init(&sd->s_sibling);
+	spin_unlock(&configfs_dirent_lock);
 	configfs_drop_dentry(sd, dentry->d_parent);
 	dput(dentry);
 	configfs_put(sd);
@@ -184,8 +193,9 @@ int configfs_unlink(struct inode *dir, struct dentry *dentry)
 		type->ct_item_ops->drop_link(parent_item,
 					       sl->sl_target);
 
-	/* FIXME: Needs lock */
+	spin_lock(&configfs_dirent_lock);
 	list_del_init(&sl->sl_list);
+	spin_unlock(&configfs_dirent_lock);
 
 	/* Put reference from create_link() */
 	config_item_put(sl->sl_target);
diff --git a/fs/dlm/config.c b/fs/dlm/config.c
index eac23bd288b..492d8caaaf2 100644
--- a/fs/dlm/config.c
+++ b/fs/dlm/config.c
@@ -41,16 +41,20 @@ struct comm;
 struct nodes;
 struct node;
 
-static struct config_group *make_cluster(struct config_group *, const char *);
+static int make_cluster(struct config_group *, const char *,
+			struct config_group **);
 static void drop_cluster(struct config_group *, struct config_item *);
 static void release_cluster(struct config_item *);
-static struct config_group *make_space(struct config_group *, const char *);
+static int make_space(struct config_group *, const char *,
+		      struct config_group **);
 static void drop_space(struct config_group *, struct config_item *);
 static void release_space(struct config_item *);
-static struct config_item *make_comm(struct config_group *, const char *);
+static int make_comm(struct config_group *, const char *,
+		     struct config_item **);
 static void drop_comm(struct config_group *, struct config_item *);
 static void release_comm(struct config_item *);
-static struct config_item *make_node(struct config_group *, const char *);
+static int make_node(struct config_group *, const char *,
+		     struct config_item **);
 static void drop_node(struct config_group *, struct config_item *);
 static void release_node(struct config_item *);
 
@@ -392,8 +396,8 @@ static struct node *to_node(struct config_item *i)
 	return i ? container_of(i, struct node, item) : NULL;
 }
 
-static struct config_group *make_cluster(struct config_group *g,
-					 const char *name)
+static int make_cluster(struct config_group *g, const char *name,
+			struct config_group **new_g)
 {
 	struct cluster *cl = NULL;
 	struct spaces *sps = NULL;
@@ -431,14 +435,15 @@ static struct config_group *make_cluster(struct config_group *g,
 
 	space_list = &sps->ss_group;
 	comm_list = &cms->cs_group;
-	return &cl->group;
+	*new_g = &cl->group;
+	return 0;
 
  fail:
 	kfree(cl);
 	kfree(gps);
 	kfree(sps);
 	kfree(cms);
-	return NULL;
+	return -ENOMEM;
 }
 
 static void drop_cluster(struct config_group *g, struct config_item *i)
@@ -466,7 +471,8 @@ static void release_cluster(struct config_item *i)
 	kfree(cl);
 }
 
-static struct config_group *make_space(struct config_group *g, const char *name)
+static int make_space(struct config_group *g, const char *name,
+		      struct config_group **new_g)
 {
 	struct space *sp = NULL;
 	struct nodes *nds = NULL;
@@ -489,13 +495,14 @@ static struct config_group *make_space(struct config_group *g, const char *name)
 	INIT_LIST_HEAD(&sp->members);
 	mutex_init(&sp->members_lock);
 	sp->members_count = 0;
-	return &sp->group;
+	*new_g = &sp->group;
+	return 0;
 
  fail:
 	kfree(sp);
 	kfree(gps);
 	kfree(nds);
-	return NULL;
+	return -ENOMEM;
 }
 
 static void drop_space(struct config_group *g, struct config_item *i)
@@ -522,19 +529,21 @@ static void release_space(struct config_item *i)
 	kfree(sp);
 }
 
-static struct config_item *make_comm(struct config_group *g, const char *name)
+static int make_comm(struct config_group *g, const char *name,
+		     struct config_item **new_i)
 {
 	struct comm *cm;
 
 	cm = kzalloc(sizeof(struct comm), GFP_KERNEL);
 	if (!cm)
-		return NULL;
+		return -ENOMEM;
 
 	config_item_init_type_name(&cm->item, name, &comm_type);
 	cm->nodeid = -1;
 	cm->local = 0;
 	cm->addr_count = 0;
-	return &cm->item;
+	*new_i = &cm->item;
+	return 0;
 }
 
 static void drop_comm(struct config_group *g, struct config_item *i)
@@ -554,14 +563,15 @@ static void release_comm(struct config_item *i)
 	kfree(cm);
 }
 
-static struct config_item *make_node(struct config_group *g, const char *name)
+static int make_node(struct config_group *g, const char *name,
+		     struct config_item **new_i)
 {
 	struct space *sp = to_space(g->cg_item.ci_parent);
 	struct node *nd;
 
 	nd = kzalloc(sizeof(struct node), GFP_KERNEL);
 	if (!nd)
-		return NULL;
+		return -ENOMEM;
 
 	config_item_init_type_name(&nd->item, name, &node_type);
 	nd->nodeid = -1;
@@ -573,7 +583,8 @@ static struct config_item *make_node(struct config_group *g, const char *name)
 	sp->members_count++;
 	mutex_unlock(&sp->members_lock);
 
-	return &nd->item;
+	*new_i = &nd->item;
+	return 0;
 }
 
 static void drop_node(struct config_group *g, struct config_item *i)
diff --git a/fs/dlm/user.c b/fs/dlm/user.c
index ebbcf38fd33..f976f303c19 100644
--- a/fs/dlm/user.c
+++ b/fs/dlm/user.c
@@ -15,6 +15,7 @@
 #include <linux/poll.h>
 #include <linux/signal.h>
 #include <linux/spinlock.h>
+#include <linux/smp_lock.h>
 #include <linux/dlm.h>
 #include <linux/dlm_device.h>
 
@@ -618,13 +619,17 @@ static int device_open(struct inode *inode, struct file *file)
 	struct dlm_user_proc *proc;
 	struct dlm_ls *ls;
 
+	lock_kernel();
 	ls = dlm_find_lockspace_device(iminor(inode));
-	if (!ls)
+	if (!ls) {
+		unlock_kernel();
 		return -ENOENT;
+	}
 
 	proc = kzalloc(sizeof(struct dlm_user_proc), GFP_KERNEL);
 	if (!proc) {
 		dlm_put_lockspace(ls);
+		unlock_kernel();
 		return -ENOMEM;
 	}
 
@@ -636,6 +641,7 @@ static int device_open(struct inode *inode, struct file *file)
 	spin_lock_init(&proc->locks_spin);
 	init_waitqueue_head(&proc->wait);
 	file->private_data = proc;
+	unlock_kernel();
 
 	return 0;
 }
@@ -870,6 +876,7 @@ static unsigned int device_poll(struct file *file, poll_table *wait)
 
 static int ctl_device_open(struct inode *inode, struct file *file)
 {
+	cycle_kernel_lock();
 	file->private_data = NULL;
 	return 0;
 }
diff --git a/fs/ecryptfs/file.c b/fs/ecryptfs/file.c
index 2258b8f654a..24749bf0668 100644
--- a/fs/ecryptfs/file.c
+++ b/fs/ecryptfs/file.c
@@ -30,6 +30,7 @@
 #include <linux/security.h>
 #include <linux/compat.h>
 #include <linux/fs_stack.h>
+#include <linux/smp_lock.h>
 #include "ecryptfs_kernel.h"
 
 /**
@@ -277,9 +278,11 @@ static int ecryptfs_fasync(int fd, struct file *file, int flag)
 	int rc = 0;
 	struct file *lower_file = NULL;
 
+	lock_kernel();
 	lower_file = ecryptfs_file_to_lower(file);
 	if (lower_file->f_op && lower_file->f_op->fasync)
 		rc = lower_file->f_op->fasync(fd, lower_file, flag);
+	unlock_kernel();
 	return rc;
 }
 
diff --git a/fs/ecryptfs/miscdev.c b/fs/ecryptfs/miscdev.c
index 50c994a249a..09a4522f65e 100644
--- a/fs/ecryptfs/miscdev.c
+++ b/fs/ecryptfs/miscdev.c
@@ -575,13 +575,11 @@ int ecryptfs_init_ecryptfs_miscdev(void)
 	int rc;
 
 	atomic_set(&ecryptfs_num_miscdev_opens, 0);
-	mutex_lock(&ecryptfs_daemon_hash_mux);
 	rc = misc_register(&ecryptfs_miscdev);
 	if (rc)
 		printk(KERN_ERR "%s: Failed to register miscellaneous device "
 		       "for communications with userspace daemons; rc = [%d]\n",
 		       __func__, rc);
-	mutex_unlock(&ecryptfs_daemon_hash_mux);
 	return rc;
 }
 
diff --git a/fs/exec.c b/fs/exec.c
index da94a6f05df..fd9234379e8 100644
--- a/fs/exec.c
+++ b/fs/exec.c
@@ -610,7 +610,7 @@ int setup_arg_pages(struct linux_binprm *bprm,
 	bprm->exec -= stack_shift;
 
 	down_write(&mm->mmap_sem);
-	vm_flags = vma->vm_flags;
+	vm_flags = VM_STACK_FLAGS;
 
 	/*
 	 * Adjust stack execute permissions; explicitly enable for
diff --git a/fs/ext3/super.c b/fs/ext3/super.c
index fe3119a71ad..2845425077e 100644
--- a/fs/ext3/super.c
+++ b/fs/ext3/super.c
@@ -2875,8 +2875,10 @@ static ssize_t ext3_quota_write(struct super_block *sb, int type,
 		blk++;
 	}
 out:
-	if (len == towrite)
+	if (len == towrite) {
+		mutex_unlock(&inode->i_mutex);
 		return err;
+	}
 	if (inode->i_size < off+len-towrite) {
 		i_size_write(inode, off+len-towrite);
 		EXT3_I(inode)->i_disksize = inode->i_size;
diff --git a/fs/ext4/balloc.c b/fs/ext4/balloc.c
index 9cc80b9cc8d..495ab21b983 100644
--- a/fs/ext4/balloc.c
+++ b/fs/ext4/balloc.c
@@ -47,7 +47,7 @@ static int ext4_block_in_group(struct super_block *sb, ext4_fsblk_t block,
 			ext4_group_t block_group)
 {
 	ext4_group_t actual_group;
-	ext4_get_group_no_and_offset(sb, block, &actual_group, 0);
+	ext4_get_group_no_and_offset(sb, block, &actual_group, NULL);
 	if (actual_group == block_group)
 		return 1;
 	return 0;
@@ -121,12 +121,7 @@ unsigned ext4_init_block_bitmap(struct super_block *sb, struct buffer_head *bh,
 				le16_to_cpu(sbi->s_es->s_reserved_gdt_blocks);
 		}
 	} else { /* For META_BG_BLOCK_GROUPS */
-		int group_rel = (block_group -
-				 le32_to_cpu(sbi->s_es->s_first_meta_bg)) %
-				EXT4_DESC_PER_BLOCK(sb);
-		if (group_rel == 0 || group_rel == 1 ||
-		    (group_rel == EXT4_DESC_PER_BLOCK(sb) - 1))
-			bit_max += 1;
+		bit_max += ext4_bg_num_gdb(sb, block_group);
 	}
 
 	if (block_group == sbi->s_groups_count - 1) {
@@ -295,7 +290,7 @@ err_out:
 	return 0;
 }
 /**
- * read_block_bitmap()
+ * ext4_read_block_bitmap()
  * @sb:			super block
  * @block_group:	given block group
  *
@@ -305,7 +300,7 @@ err_out:
  * Return buffer_head on success or NULL in case of failure.
  */
 struct buffer_head *
-read_block_bitmap(struct super_block *sb, ext4_group_t block_group)
+ext4_read_block_bitmap(struct super_block *sb, ext4_group_t block_group)
 {
 	struct ext4_group_desc * desc;
 	struct buffer_head * bh = NULL;
@@ -409,8 +404,7 @@ restart:
 		prev = rsv;
 	}
 	printk("Window map complete.\n");
-	if (bad)
-		BUG();
+	BUG_ON(bad);
 }
 #define rsv_window_dump(root, verbose) \
 	__rsv_window_dump((root), (verbose), __func__)
@@ -694,7 +688,7 @@ do_more:
 		count -= overflow;
 	}
 	brelse(bitmap_bh);
-	bitmap_bh = read_block_bitmap(sb, block_group);
+	bitmap_bh = ext4_read_block_bitmap(sb, block_group);
 	if (!bitmap_bh)
 		goto error_return;
 	desc = ext4_get_group_desc (sb, block_group, &gd_bh);
@@ -810,6 +804,13 @@ do_more:
 	spin_unlock(sb_bgl_lock(sbi, block_group));
 	percpu_counter_add(&sbi->s_freeblocks_counter, count);
 
+	if (sbi->s_log_groups_per_flex) {
+		ext4_group_t flex_group = ext4_flex_group(sbi, block_group);
+		spin_lock(sb_bgl_lock(sbi, flex_group));
+		sbi->s_flex_groups[flex_group].free_blocks += count;
+		spin_unlock(sb_bgl_lock(sbi, flex_group));
+	}
+
 	/* We dirtied the bitmap block */
 	BUFFER_TRACE(bitmap_bh, "dirtied bitmap block");
 	err = ext4_journal_dirty_metadata(handle, bitmap_bh);
@@ -1598,23 +1599,35 @@ out:
 
 /**
  * ext4_has_free_blocks()
- * @sbi:		in-core super block structure.
+ * @sbi:	in-core super block structure.
+ * @nblocks:	number of neeed blocks
  *
- * Check if filesystem has at least 1 free block available for allocation.
+ * Check if filesystem has free blocks available for allocation.
+ * Return the number of blocks avaible for allocation for this request
+ * On success, return nblocks
  */
-static int ext4_has_free_blocks(struct ext4_sb_info *sbi)
+ext4_fsblk_t ext4_has_free_blocks(struct ext4_sb_info *sbi,
+						ext4_fsblk_t nblocks)
 {
-	ext4_fsblk_t free_blocks, root_blocks;
+	ext4_fsblk_t free_blocks;
+	ext4_fsblk_t root_blocks = 0;
 
 	free_blocks = percpu_counter_read_positive(&sbi->s_freeblocks_counter);
-	root_blocks = ext4_r_blocks_count(sbi->s_es);
-	if (free_blocks < root_blocks + 1 && !capable(CAP_SYS_RESOURCE) &&
+
+	if (!capable(CAP_SYS_RESOURCE) &&
 		sbi->s_resuid != current->fsuid &&
-		(sbi->s_resgid == 0 || !in_group_p (sbi->s_resgid))) {
-		return 0;
-	}
-	return 1;
-}
+		(sbi->s_resgid == 0 || !in_group_p(sbi->s_resgid)))
+		root_blocks = ext4_r_blocks_count(sbi->s_es);
+#ifdef CONFIG_SMP
+	if (free_blocks - root_blocks < FBC_BATCH)
+		free_blocks =
+			percpu_counter_sum_and_set(&sbi->s_freeblocks_counter);
+#endif
+	if (free_blocks - root_blocks < nblocks)
+		return free_blocks - root_blocks;
+	return nblocks;
+ }
+
 
 /**
  * ext4_should_retry_alloc()
@@ -1630,7 +1643,7 @@ static int ext4_has_free_blocks(struct ext4_sb_info *sbi)
  */
 int ext4_should_retry_alloc(struct super_block *sb, int *retries)
 {
-	if (!ext4_has_free_blocks(EXT4_SB(sb)) || (*retries)++ > 3)
+	if (!ext4_has_free_blocks(EXT4_SB(sb), 1) || (*retries)++ > 3)
 		return 0;
 
 	jbd_debug(1, "%s: retrying operation after ENOSPC\n", sb->s_id);
@@ -1639,20 +1652,24 @@ int ext4_should_retry_alloc(struct super_block *sb, int *retries)
 }
 
 /**
- * ext4_new_blocks_old() -- core block(s) allocation function
+ * ext4_old_new_blocks() -- core block bitmap based block allocation function
+ *
  * @handle:		handle to this transaction
  * @inode:		file inode
  * @goal:		given target block(filesystem wide)
  * @count:		target number of blocks to allocate
  * @errp:		error code
  *
- * ext4_new_blocks uses a goal block to assist allocation.  It tries to
- * allocate block(s) from the block group contains the goal block first. If that
- * fails, it will try to allocate block(s) from other block groups without
- * any specific goal block.
+ * ext4_old_new_blocks uses a goal block to assist allocation and look up
+ * the block bitmap directly to do block allocation.  It tries to
+ * allocate block(s) from the block group contains the goal block first. If
+ * that fails, it will try to allocate block(s) from other block groups
+ * without any specific goal block.
+ *
+ * This function is called when -o nomballoc mount option is enabled
  *
  */
-ext4_fsblk_t ext4_new_blocks_old(handle_t *handle, struct inode *inode,
+ext4_fsblk_t ext4_old_new_blocks(handle_t *handle, struct inode *inode,
 			ext4_fsblk_t goal, unsigned long *count, int *errp)
 {
 	struct buffer_head *bitmap_bh = NULL;
@@ -1676,13 +1693,26 @@ ext4_fsblk_t ext4_new_blocks_old(handle_t *handle, struct inode *inode,
 	ext4_group_t ngroups;
 	unsigned long num = *count;
 
-	*errp = -ENOSPC;
 	sb = inode->i_sb;
 	if (!sb) {
+		*errp = -ENODEV;
 		printk("ext4_new_block: nonexistent device");
 		return 0;
 	}
 
+	sbi = EXT4_SB(sb);
+	if (!EXT4_I(inode)->i_delalloc_reserved_flag) {
+		/*
+		 * With delalloc we already reserved the blocks
+		 */
+		*count = ext4_has_free_blocks(sbi, *count);
+	}
+	if (*count == 0) {
+		*errp = -ENOSPC;
+		return 0;	/*return with ENOSPC error */
+	}
+	num = *count;
+
 	/*
 	 * Check quota for allocation of this block.
 	 */
@@ -1706,11 +1736,6 @@ ext4_fsblk_t ext4_new_blocks_old(handle_t *handle, struct inode *inode,
 	if (block_i && ((windowsz = block_i->rsv_window_node.rsv_goal_size) > 0))
 		my_rsv = &block_i->rsv_window_node;
 
-	if (!ext4_has_free_blocks(sbi)) {
-		*errp = -ENOSPC;
-		goto out;
-	}
-
 	/*
 	 * First, test whether the goal block is free.
 	 */
@@ -1734,7 +1759,7 @@ retry_alloc:
 		my_rsv = NULL;
 
 	if (free_blocks > 0) {
-		bitmap_bh = read_block_bitmap(sb, group_no);
+		bitmap_bh = ext4_read_block_bitmap(sb, group_no);
 		if (!bitmap_bh)
 			goto io_error;
 		grp_alloc_blk = ext4_try_to_allocate_with_rsv(sb, handle,
@@ -1770,7 +1795,7 @@ retry_alloc:
 			continue;
 
 		brelse(bitmap_bh);
-		bitmap_bh = read_block_bitmap(sb, group_no);
+		bitmap_bh = ext4_read_block_bitmap(sb, group_no);
 		if (!bitmap_bh)
 			goto io_error;
 		/*
@@ -1882,7 +1907,15 @@ allocated:
 	le16_add_cpu(&gdp->bg_free_blocks_count, -num);
 	gdp->bg_checksum = ext4_group_desc_csum(sbi, group_no, gdp);
 	spin_unlock(sb_bgl_lock(sbi, group_no));
-	percpu_counter_sub(&sbi->s_freeblocks_counter, num);
+	if (!EXT4_I(inode)->i_delalloc_reserved_flag)
+		percpu_counter_sub(&sbi->s_freeblocks_counter, num);
+
+	if (sbi->s_log_groups_per_flex) {
+		ext4_group_t flex_group = ext4_flex_group(sbi, group_no);
+		spin_lock(sb_bgl_lock(sbi, flex_group));
+		sbi->s_flex_groups[flex_group].free_blocks -= num;
+		spin_unlock(sb_bgl_lock(sbi, flex_group));
+	}
 
 	BUFFER_TRACE(gdp_bh, "journal_dirty_metadata for group descriptor");
 	err = ext4_journal_dirty_metadata(handle, gdp_bh);
@@ -1915,46 +1948,104 @@ out:
 	return 0;
 }
 
-ext4_fsblk_t ext4_new_block(handle_t *handle, struct inode *inode,
-		ext4_fsblk_t goal, int *errp)
+#define EXT4_META_BLOCK 0x1
+
+static ext4_fsblk_t do_blk_alloc(handle_t *handle, struct inode *inode,
+				ext4_lblk_t iblock, ext4_fsblk_t goal,
+				unsigned long *count, int *errp, int flags)
 {
 	struct ext4_allocation_request ar;
 	ext4_fsblk_t ret;
 
 	if (!test_opt(inode->i_sb, MBALLOC)) {
-		unsigned long count = 1;
-		ret = ext4_new_blocks_old(handle, inode, goal, &count, errp);
-		return ret;
+		return ext4_old_new_blocks(handle, inode, goal, count, errp);
 	}
 
 	memset(&ar, 0, sizeof(ar));
+	/* Fill with neighbour allocated blocks */
+
 	ar.inode = inode;
 	ar.goal = goal;
-	ar.len = 1;
+	ar.len = *count;
+	ar.logical = iblock;
+
+	if (S_ISREG(inode->i_mode) && !(flags & EXT4_META_BLOCK))
+		/* enable in-core preallocation for data block allocation */
+		ar.flags = EXT4_MB_HINT_DATA;
+	else
+		/* disable in-core preallocation for non-regular files */
+		ar.flags = 0;
+
 	ret = ext4_mb_new_blocks(handle, &ar, errp);
+	*count = ar.len;
 	return ret;
 }
 
-ext4_fsblk_t ext4_new_blocks(handle_t *handle, struct inode *inode,
+/*
+ * ext4_new_meta_blocks() -- allocate block for meta data (indexing) blocks
+ *
+ * @handle:             handle to this transaction
+ * @inode:              file inode
+ * @goal:               given target block(filesystem wide)
+ * @count:		total number of blocks need
+ * @errp:               error code
+ *
+ * Return 1st allocated block numberon success, *count stores total account
+ * error stores in errp pointer
+ */
+ext4_fsblk_t ext4_new_meta_blocks(handle_t *handle, struct inode *inode,
 		ext4_fsblk_t goal, unsigned long *count, int *errp)
 {
-	struct ext4_allocation_request ar;
 	ext4_fsblk_t ret;
-
-	if (!test_opt(inode->i_sb, MBALLOC)) {
-		ret = ext4_new_blocks_old(handle, inode, goal, count, errp);
-		return ret;
+	ret = do_blk_alloc(handle, inode, 0, goal,
+				count, errp, EXT4_META_BLOCK);
+	/*
+	 * Account for the allocated meta blocks
+	 */
+	if (!(*errp)) {
+		spin_lock(&EXT4_I(inode)->i_block_reservation_lock);
+		EXT4_I(inode)->i_allocated_meta_blocks += *count;
+		spin_unlock(&EXT4_I(inode)->i_block_reservation_lock);
 	}
-
-	memset(&ar, 0, sizeof(ar));
-	ar.inode = inode;
-	ar.goal = goal;
-	ar.len = *count;
-	ret = ext4_mb_new_blocks(handle, &ar, errp);
-	*count = ar.len;
 	return ret;
 }
 
+/*
+ * ext4_new_meta_block() -- allocate block for meta data (indexing) blocks
+ *
+ * @handle:             handle to this transaction
+ * @inode:              file inode
+ * @goal:               given target block(filesystem wide)
+ * @errp:               error code
+ *
+ * Return allocated block number on success
+ */
+ext4_fsblk_t ext4_new_meta_block(handle_t *handle, struct inode *inode,
+		ext4_fsblk_t goal, int *errp)
+{
+	unsigned long count = 1;
+	return ext4_new_meta_blocks(handle, inode, goal, &count, errp);
+}
+
+/*
+ * ext4_new_blocks() -- allocate data blocks
+ *
+ * @handle:             handle to this transaction
+ * @inode:              file inode
+ * @goal:               given target block(filesystem wide)
+ * @count:		total number of blocks need
+ * @errp:               error code
+ *
+ * Return 1st allocated block numberon success, *count stores total account
+ * error stores in errp pointer
+ */
+
+ext4_fsblk_t ext4_new_blocks(handle_t *handle, struct inode *inode,
+				ext4_lblk_t iblock, ext4_fsblk_t goal,
+				unsigned long *count, int *errp)
+{
+	return do_blk_alloc(handle, inode, iblock, goal, count, errp, 0);
+}
 
 /**
  * ext4_count_free_blocks() -- count filesystem free blocks
@@ -1986,7 +2077,7 @@ ext4_fsblk_t ext4_count_free_blocks(struct super_block *sb)
 			continue;
 		desc_count += le16_to_cpu(gdp->bg_free_blocks_count);
 		brelse(bitmap_bh);
-		bitmap_bh = read_block_bitmap(sb, i);
+		bitmap_bh = ext4_read_block_bitmap(sb, i);
 		if (bitmap_bh == NULL)
 			continue;
 
diff --git a/fs/ext4/dir.c b/fs/ext4/dir.c
index 2bf0331ea19..d3d23d73c08 100644
--- a/fs/ext4/dir.c
+++ b/fs/ext4/dir.c
@@ -129,7 +129,8 @@ static int ext4_readdir(struct file * filp,
 		struct buffer_head *bh = NULL;
 
 		map_bh.b_state = 0;
-		err = ext4_get_blocks_wrap(NULL, inode, blk, 1, &map_bh, 0, 0);
+		err = ext4_get_blocks_wrap(NULL, inode, blk, 1, &map_bh,
+						0, 0, 0);
 		if (err > 0) {
 			pgoff_t index = map_bh.b_blocknr >>
 					(PAGE_CACHE_SHIFT - inode->i_blkbits);
@@ -272,7 +273,7 @@ static void free_rb_tree_fname(struct rb_root *root)
 
 	while (n) {
 		/* Do the node's children first */
-		if ((n)->rb_left) {
+		if (n->rb_left) {
 			n = n->rb_left;
 			continue;
 		}
@@ -301,24 +302,18 @@ static void free_rb_tree_fname(struct rb_root *root)
 			parent->rb_right = NULL;
 		n = parent;
 	}
-	root->rb_node = NULL;
 }
 
 
-static struct dir_private_info *create_dir_info(loff_t pos)
+static struct dir_private_info *ext4_htree_create_dir_info(loff_t pos)
 {
 	struct dir_private_info *p;
 
-	p = kmalloc(sizeof(struct dir_private_info), GFP_KERNEL);
+	p = kzalloc(sizeof(struct dir_private_info), GFP_KERNEL);
 	if (!p)
 		return NULL;
-	p->root.rb_node = NULL;
-	p->curr_node = NULL;
-	p->extra_fname = NULL;
-	p->last_pos = 0;
 	p->curr_hash = pos2maj_hash(pos);
 	p->curr_minor_hash = pos2min_hash(pos);
-	p->next_hash = 0;
 	return p;
 }
 
@@ -433,7 +428,7 @@ static int ext4_dx_readdir(struct file * filp,
 	int	ret;
 
 	if (!info) {
-		info = create_dir_info(filp->f_pos);
+		info = ext4_htree_create_dir_info(filp->f_pos);
 		if (!info)
 			return -ENOMEM;
 		filp->private_data = info;
diff --git a/fs/ext4/ext4.h b/fs/ext4/ext4.h
index 8158083f7ac..303e41cf7b1 100644
--- a/fs/ext4/ext4.h
+++ b/fs/ext4/ext4.h
@@ -22,7 +22,7 @@
 #include "ext4_i.h"
 
 /*
- * The second extended filesystem constants/structures
+ * The fourth extended filesystem constants/structures
  */
 
 /*
@@ -45,7 +45,7 @@
 #define ext4_debug(f, a...)						\
 	do {								\
 		printk (KERN_DEBUG "EXT4-fs DEBUG (%s, %d): %s:",	\
-			__FILE__, __LINE__, __FUNCTION__);		\
+			__FILE__, __LINE__, __func__);			\
 		printk (KERN_DEBUG f, ## a);				\
 	} while (0)
 #else
@@ -74,6 +74,9 @@
 #define EXT4_MB_HINT_GOAL_ONLY		256
 /* goal is meaningful */
 #define EXT4_MB_HINT_TRY_GOAL		512
+/* blocks already pre-reserved by delayed allocation */
+#define EXT4_MB_DELALLOC_RESERVED      1024
+
 
 struct ext4_allocation_request {
 	/* target inode for block we're allocating */
@@ -170,6 +173,15 @@ struct ext4_group_desc
 	__u32	bg_reserved2[3];
 };
 
+/*
+ * Structure of a flex block group info
+ */
+
+struct flex_groups {
+	__u32 free_inodes;
+	__u32 free_blocks;
+};
+
 #define EXT4_BG_INODE_UNINIT	0x0001 /* Inode table/bitmap not in use */
 #define EXT4_BG_BLOCK_UNINIT	0x0002 /* Block bitmap not in use */
 #define EXT4_BG_INODE_ZEROED	0x0004 /* On-disk itable initialized to zero */
@@ -527,6 +539,7 @@ do {									       \
 #define EXT4_MOUNT_JOURNAL_ASYNC_COMMIT	0x1000000 /* Journal Async Commit */
 #define EXT4_MOUNT_I_VERSION            0x2000000 /* i_version support */
 #define EXT4_MOUNT_MBALLOC		0x4000000 /* Buddy allocation support */
+#define EXT4_MOUNT_DELALLOC		0x8000000 /* Delalloc support */
 /* Compatibility, for having both ext2_fs.h and ext4_fs.h included at once */
 #ifndef _LINUX_EXT2_FS_H
 #define clear_opt(o, opt)		o &= ~EXT4_MOUNT_##opt
@@ -647,7 +660,10 @@ struct ext4_super_block {
 	__le16  s_mmp_interval;         /* # seconds to wait in MMP checking */
 	__le64  s_mmp_block;            /* Block for multi-mount protection */
 	__le32  s_raid_stripe_width;    /* blocks on all data disks (N*stride)*/
-	__u32   s_reserved[163];        /* Padding to the end of the block */
+	__u8	s_log_groups_per_flex;  /* FLEX_BG group size */
+	__u8	s_reserved_char_pad2;
+	__le16  s_reserved_pad;
+	__u32   s_reserved[162];        /* Padding to the end of the block */
 };
 
 #ifdef __KERNEL__
@@ -958,12 +974,17 @@ extern ext4_grpblk_t ext4_block_group_offset(struct super_block *sb,
 extern int ext4_bg_has_super(struct super_block *sb, ext4_group_t group);
 extern unsigned long ext4_bg_num_gdb(struct super_block *sb,
 			ext4_group_t group);
-extern ext4_fsblk_t ext4_new_block (handle_t *handle, struct inode *inode,
+extern ext4_fsblk_t ext4_new_meta_block(handle_t *handle, struct inode *inode,
 			ext4_fsblk_t goal, int *errp);
-extern ext4_fsblk_t ext4_new_blocks (handle_t *handle, struct inode *inode,
+extern ext4_fsblk_t ext4_new_meta_blocks(handle_t *handle, struct inode *inode,
 			ext4_fsblk_t goal, unsigned long *count, int *errp);
-extern ext4_fsblk_t ext4_new_blocks_old(handle_t *handle, struct inode *inode,
+extern ext4_fsblk_t ext4_new_blocks(handle_t *handle, struct inode *inode,
+					ext4_lblk_t iblock, ext4_fsblk_t goal,
+					unsigned long *count, int *errp);
+extern ext4_fsblk_t ext4_old_new_blocks(handle_t *handle, struct inode *inode,
 			ext4_fsblk_t goal, unsigned long *count, int *errp);
+extern ext4_fsblk_t ext4_has_free_blocks(struct ext4_sb_info *sbi,
+						ext4_fsblk_t nblocks);
 extern void ext4_free_blocks (handle_t *handle, struct inode *inode,
 			ext4_fsblk_t block, unsigned long count, int metadata);
 extern void ext4_free_blocks_sb (handle_t *handle, struct super_block *sb,
@@ -1016,9 +1037,14 @@ extern int __init init_ext4_mballoc(void);
 extern void exit_ext4_mballoc(void);
 extern void ext4_mb_free_blocks(handle_t *, struct inode *,
 		unsigned long, unsigned long, int, unsigned long *);
+extern int ext4_mb_add_more_groupinfo(struct super_block *sb,
+		ext4_group_t i, struct ext4_group_desc *desc);
+extern void ext4_mb_update_group_info(struct ext4_group_info *grp,
+		ext4_grpblk_t add);
 
 
 /* inode.c */
+void ext4_da_release_space(struct inode *inode, int used, int to_free);
 int ext4_forget(handle_t *handle, int is_metadata, struct inode *inode,
 		struct buffer_head *bh, ext4_fsblk_t blocknr);
 struct buffer_head *ext4_getblk(handle_t *, struct inode *,
@@ -1033,19 +1059,23 @@ int ext4_get_blocks_handle(handle_t *handle, struct inode *inode,
 extern struct inode *ext4_iget(struct super_block *, unsigned long);
 extern int  ext4_write_inode (struct inode *, int);
 extern int  ext4_setattr (struct dentry *, struct iattr *);
+extern int  ext4_getattr(struct vfsmount *mnt, struct dentry *dentry,
+				struct kstat *stat);
 extern void ext4_delete_inode (struct inode *);
 extern int  ext4_sync_inode (handle_t *, struct inode *);
 extern void ext4_discard_reservation (struct inode *);
 extern void ext4_dirty_inode(struct inode *);
 extern int ext4_change_inode_journal_flag(struct inode *, int);
 extern int ext4_get_inode_loc(struct inode *, struct ext4_iloc *);
+extern int ext4_can_truncate(struct inode *inode);
 extern void ext4_truncate (struct inode *);
 extern void ext4_set_inode_flags(struct inode *);
 extern void ext4_get_inode_flags(struct ext4_inode_info *);
 extern void ext4_set_aops(struct inode *inode);
 extern int ext4_writepage_trans_blocks(struct inode *);
-extern int ext4_block_truncate_page(handle_t *handle, struct page *page,
+extern int ext4_block_truncate_page(handle_t *handle,
 		struct address_space *mapping, loff_t from);
+extern int ext4_page_mkwrite(struct vm_area_struct *vma, struct page *page);
 
 /* ioctl.c */
 extern long ext4_ioctl(struct file *, unsigned int, unsigned long);
@@ -1159,10 +1189,21 @@ struct ext4_group_info *ext4_get_group_info(struct super_block *sb,
 }
 
 
+static inline ext4_group_t ext4_flex_group(struct ext4_sb_info *sbi,
+					     ext4_group_t block_group)
+{
+	return block_group >> sbi->s_log_groups_per_flex;
+}
+
+static inline unsigned int ext4_flex_bg_size(struct ext4_sb_info *sbi)
+{
+	return 1 << sbi->s_log_groups_per_flex;
+}
+
 #define ext4_std_error(sb, errno)				\
 do {								\
 	if ((errno))						\
-		__ext4_std_error((sb), __FUNCTION__, (errno));	\
+		__ext4_std_error((sb), __func__, (errno));	\
 } while (0)
 
 /*
@@ -1191,7 +1232,7 @@ extern int ext4_ext_get_blocks(handle_t *handle, struct inode *inode,
 			ext4_lblk_t iblock,
 			unsigned long max_blocks, struct buffer_head *bh_result,
 			int create, int extend_disksize);
-extern void ext4_ext_truncate(struct inode *, struct page *);
+extern void ext4_ext_truncate(struct inode *);
 extern void ext4_ext_init(struct super_block *);
 extern void ext4_ext_release(struct super_block *);
 extern long ext4_fallocate(struct inode *inode, int mode, loff_t offset,
@@ -1199,7 +1240,7 @@ extern long ext4_fallocate(struct inode *inode, int mode, loff_t offset,
 extern int ext4_get_blocks_wrap(handle_t *handle, struct inode *inode,
 			sector_t block, unsigned long max_blocks,
 			struct buffer_head *bh, int create,
-			int extend_disksize);
+			int extend_disksize, int flag);
 #endif	/* __KERNEL__ */
 
 #endif	/* _EXT4_H */
diff --git a/fs/ext4/ext4_extents.h b/fs/ext4/ext4_extents.h
index 75333b595fa..6c166c0a54b 100644
--- a/fs/ext4/ext4_extents.h
+++ b/fs/ext4/ext4_extents.h
@@ -212,6 +212,7 @@ static inline int ext4_ext_get_actual_len(struct ext4_extent *ext)
 		(le16_to_cpu(ext->ee_len) - EXT_INIT_MAX_LEN));
 }
 
+extern int ext4_ext_calc_metadata_amount(struct inode *inode, int blocks);
 extern ext4_fsblk_t idx_pblock(struct ext4_extent_idx *);
 extern void ext4_ext_store_pblock(struct ext4_extent *, ext4_fsblk_t);
 extern int ext4_extent_tree_init(handle_t *, struct inode *);
diff --git a/fs/ext4/ext4_i.h b/fs/ext4/ext4_i.h
index 26a4ae255d7..ef7409f0e7e 100644
--- a/fs/ext4/ext4_i.h
+++ b/fs/ext4/ext4_i.h
@@ -79,7 +79,7 @@ struct ext4_ext_cache {
 };
 
 /*
- * third extended file system inode data in memory
+ * fourth extended file system inode data in memory
  */
 struct ext4_inode_info {
 	__le32	i_data[15];	/* unconverted */
@@ -150,6 +150,7 @@ struct ext4_inode_info {
 	 */
 	struct rw_semaphore i_data_sem;
 	struct inode vfs_inode;
+	struct jbd2_inode jinode;
 
 	unsigned long i_ext_generation;
 	struct ext4_ext_cache i_cached_extent;
@@ -162,6 +163,13 @@ struct ext4_inode_info {
 	/* mballoc */
 	struct list_head i_prealloc_list;
 	spinlock_t i_prealloc_lock;
+
+	/* allocation reservation info for delalloc */
+	unsigned long i_reserved_data_blocks;
+	unsigned long i_reserved_meta_blocks;
+	unsigned long i_allocated_meta_blocks;
+	unsigned short i_delalloc_reserved_flag;
+	spinlock_t i_block_reservation_lock;
 };
 
 #endif	/* _EXT4_I */
diff --git a/fs/ext4/ext4_jbd2.h b/fs/ext4/ext4_jbd2.h
index 9255a7d28b2..eb8bc3afe6e 100644
--- a/fs/ext4/ext4_jbd2.h
+++ b/fs/ext4/ext4_jbd2.h
@@ -142,19 +142,17 @@ int __ext4_journal_dirty_metadata(const char *where,
 				handle_t *handle, struct buffer_head *bh);
 
 #define ext4_journal_get_undo_access(handle, bh) \
-	__ext4_journal_get_undo_access(__FUNCTION__, (handle), (bh))
+	__ext4_journal_get_undo_access(__func__, (handle), (bh))
 #define ext4_journal_get_write_access(handle, bh) \
-	__ext4_journal_get_write_access(__FUNCTION__, (handle), (bh))
+	__ext4_journal_get_write_access(__func__, (handle), (bh))
 #define ext4_journal_revoke(handle, blocknr, bh) \
-	__ext4_journal_revoke(__FUNCTION__, (handle), (blocknr), (bh))
+	__ext4_journal_revoke(__func__, (handle), (blocknr), (bh))
 #define ext4_journal_get_create_access(handle, bh) \
-	__ext4_journal_get_create_access(__FUNCTION__, (handle), (bh))
+	__ext4_journal_get_create_access(__func__, (handle), (bh))
 #define ext4_journal_dirty_metadata(handle, bh) \
-	__ext4_journal_dirty_metadata(__FUNCTION__, (handle), (bh))
+	__ext4_journal_dirty_metadata(__func__, (handle), (bh))
 #define ext4_journal_forget(handle, bh) \
-	__ext4_journal_forget(__FUNCTION__, (handle), (bh))
-
-int ext4_journal_dirty_data(handle_t *handle, struct buffer_head *bh);
+	__ext4_journal_forget(__func__, (handle), (bh))
 
 handle_t *ext4_journal_start_sb(struct super_block *sb, int nblocks);
 int __ext4_journal_stop(const char *where, handle_t *handle);
@@ -165,7 +163,7 @@ static inline handle_t *ext4_journal_start(struct inode *inode, int nblocks)
 }
 
 #define ext4_journal_stop(handle) \
-	__ext4_journal_stop(__FUNCTION__, (handle))
+	__ext4_journal_stop(__func__, (handle))
 
 static inline handle_t *ext4_journal_current_handle(void)
 {
@@ -192,6 +190,11 @@ static inline int ext4_journal_force_commit(journal_t *journal)
 	return jbd2_journal_force_commit(journal);
 }
 
+static inline int ext4_jbd2_file_inode(handle_t *handle, struct inode *inode)
+{
+	return jbd2_journal_file_inode(handle, &EXT4_I(inode)->jinode);
+}
+
 /* super.c */
 int ext4_force_commit(struct super_block *sb);
 
diff --git a/fs/ext4/ext4_sb.h b/fs/ext4/ext4_sb.h
index 5802e69f219..6300226d553 100644
--- a/fs/ext4/ext4_sb.h
+++ b/fs/ext4/ext4_sb.h
@@ -25,7 +25,7 @@
 #include <linux/rbtree.h>
 
 /*
- * third extended-fs super-block data in memory
+ * fourth extended-fs super-block data in memory
  */
 struct ext4_sb_info {
 	unsigned long s_desc_size;	/* Size of a group descriptor in bytes */
@@ -143,6 +143,9 @@ struct ext4_sb_info {
 
 	/* locality groups */
 	struct ext4_locality_group *s_locality_groups;
+
+	unsigned int s_log_groups_per_flex;
+	struct flex_groups *s_flex_groups;
 };
 
 #endif	/* _EXT4_SB */
diff --git a/fs/ext4/extents.c b/fs/ext4/extents.c
index 47929c4e3da..42c4c0c892e 100644
--- a/fs/ext4/extents.c
+++ b/fs/ext4/extents.c
@@ -92,17 +92,16 @@ static void ext4_idx_store_pblock(struct ext4_extent_idx *ix, ext4_fsblk_t pb)
 	ix->ei_leaf_hi = cpu_to_le16((unsigned long) ((pb >> 31) >> 1) & 0xffff);
 }
 
-static handle_t *ext4_ext_journal_restart(handle_t *handle, int needed)
+static int ext4_ext_journal_restart(handle_t *handle, int needed)
 {
 	int err;
 
 	if (handle->h_buffer_credits > needed)
-		return handle;
-	if (!ext4_journal_extend(handle, needed))
-		return handle;
-	err = ext4_journal_restart(handle, needed);
-
-	return handle;
+		return 0;
+	err = ext4_journal_extend(handle, needed);
+	if (err)
+		return err;
+	return ext4_journal_restart(handle, needed);
 }
 
 /*
@@ -180,15 +179,18 @@ static ext4_fsblk_t ext4_ext_find_goal(struct inode *inode,
 	return bg_start + colour + block;
 }
 
+/*
+ * Allocation for a meta data block
+ */
 static ext4_fsblk_t
-ext4_ext_new_block(handle_t *handle, struct inode *inode,
+ext4_ext_new_meta_block(handle_t *handle, struct inode *inode,
 			struct ext4_ext_path *path,
 			struct ext4_extent *ex, int *err)
 {
 	ext4_fsblk_t goal, newblock;
 
 	goal = ext4_ext_find_goal(inode, path, le32_to_cpu(ex->ee_block));
-	newblock = ext4_new_block(handle, inode, goal, err);
+	newblock = ext4_new_meta_block(handle, inode, goal, err);
 	return newblock;
 }
 
@@ -246,6 +248,36 @@ static int ext4_ext_space_root_idx(struct inode *inode)
 	return size;
 }
 
+/*
+ * Calculate the number of metadata blocks needed
+ * to allocate @blocks
+ * Worse case is one block per extent
+ */
+int ext4_ext_calc_metadata_amount(struct inode *inode, int blocks)
+{
+	int lcap, icap, rcap, leafs, idxs, num;
+	int newextents = blocks;
+
+	rcap = ext4_ext_space_root_idx(inode);
+	lcap = ext4_ext_space_block(inode);
+	icap = ext4_ext_space_block_idx(inode);
+
+	/* number of new leaf blocks needed */
+	num = leafs = (newextents + lcap - 1) / lcap;
+
+	/*
+	 * Worse case, we need separate index block(s)
+	 * to link all new leaf blocks
+	 */
+	idxs = (leafs + icap - 1) / icap;
+	do {
+		num += idxs;
+		idxs = (idxs + icap - 1) / icap;
+	} while (idxs > rcap);
+
+	return num;
+}
+
 static int
 ext4_ext_max_entries(struct inode *inode, int depth)
 {
@@ -524,6 +556,7 @@ ext4_ext_find_extent(struct inode *inode, ext4_lblk_t block,
 		alloc = 1;
 	}
 	path[0].p_hdr = eh;
+	path[0].p_bh = NULL;
 
 	i = depth;
 	/* walk through the tree */
@@ -552,12 +585,14 @@ ext4_ext_find_extent(struct inode *inode, ext4_lblk_t block,
 	}
 
 	path[ppos].p_depth = i;
-	path[ppos].p_hdr = eh;
 	path[ppos].p_ext = NULL;
 	path[ppos].p_idx = NULL;
 
 	/* find extent */
 	ext4_ext_binsearch(inode, path + ppos, block);
+	/* if not an empty leaf */
+	if (path[ppos].p_ext)
+		path[ppos].p_block = ext_pblock(path[ppos].p_ext);
 
 	ext4_ext_show_path(inode, path);
 
@@ -688,7 +723,8 @@ static int ext4_ext_split(handle_t *handle, struct inode *inode,
 	/* allocate all needed blocks */
 	ext_debug("allocate %d blocks for indexes/leaf\n", depth - at);
 	for (a = 0; a < depth - at; a++) {
-		newblock = ext4_ext_new_block(handle, inode, path, newext, &err);
+		newblock = ext4_ext_new_meta_block(handle, inode, path,
+						   newext, &err);
 		if (newblock == 0)
 			goto cleanup;
 		ablocks[a] = newblock;
@@ -884,7 +920,7 @@ static int ext4_ext_grow_indepth(handle_t *handle, struct inode *inode,
 	ext4_fsblk_t newblock;
 	int err = 0;
 
-	newblock = ext4_ext_new_block(handle, inode, path, newext, &err);
+	newblock = ext4_ext_new_meta_block(handle, inode, path, newext, &err);
 	if (newblock == 0)
 		return err;
 
@@ -981,6 +1017,8 @@ repeat:
 		/* if we found index with free entry, then use that
 		 * entry: create all needed subtree and add new leaf */
 		err = ext4_ext_split(handle, inode, path, newext, i);
+		if (err)
+			goto out;
 
 		/* refill path */
 		ext4_ext_drop_refs(path);
@@ -1883,11 +1921,9 @@ ext4_ext_rm_leaf(handle_t *handle, struct inode *inode,
 		credits += 2 * EXT4_QUOTA_TRANS_BLOCKS(inode->i_sb);
 #endif
 
-		handle = ext4_ext_journal_restart(handle, credits);
-		if (IS_ERR(handle)) {
-			err = PTR_ERR(handle);
+		err = ext4_ext_journal_restart(handle, credits);
+		if (err)
 			goto out;
-		}
 
 		err = ext4_ext_get_access(handle, inode, path + depth);
 		if (err)
@@ -2529,6 +2565,7 @@ int ext4_ext_get_blocks(handle_t *handle, struct inode *inode,
 	int err = 0, depth, ret;
 	unsigned long allocated = 0;
 	struct ext4_allocation_request ar;
+	loff_t disksize;
 
 	__clear_bit(BH_New, &bh_result->b_state);
 	ext_debug("blocks %u/%lu requested for inode %u\n",
@@ -2616,8 +2653,7 @@ int ext4_ext_get_blocks(handle_t *handle, struct inode *inode,
 				 */
 				if (allocated > max_blocks)
 					allocated = max_blocks;
-				/* mark the buffer unwritten */
-				__set_bit(BH_Unwritten, &bh_result->b_state);
+				set_buffer_unwritten(bh_result);
 				goto out2;
 			}
 
@@ -2716,14 +2752,19 @@ int ext4_ext_get_blocks(handle_t *handle, struct inode *inode,
 		goto out2;
 	}
 
-	if (extend_disksize && inode->i_size > EXT4_I(inode)->i_disksize)
-		EXT4_I(inode)->i_disksize = inode->i_size;
-
 	/* previous routine could use block we allocated */
 	newblock = ext_pblock(&newex);
 	allocated = ext4_ext_get_actual_len(&newex);
 outnew:
-	__set_bit(BH_New, &bh_result->b_state);
+	if (extend_disksize) {
+		disksize = ((loff_t) iblock + ar.len) << inode->i_blkbits;
+		if (disksize > i_size_read(inode))
+			disksize = i_size_read(inode);
+		if (disksize > EXT4_I(inode)->i_disksize)
+			EXT4_I(inode)->i_disksize = disksize;
+	}
+
+	set_buffer_new(bh_result);
 
 	/* Cache only when it is _not_ an uninitialized extent */
 	if (create != EXT4_CREATE_UNINITIALIZED_EXT)
@@ -2733,7 +2774,7 @@ out:
 	if (allocated > max_blocks)
 		allocated = max_blocks;
 	ext4_ext_show_leaf(inode, path);
-	__set_bit(BH_Mapped, &bh_result->b_state);
+	set_buffer_mapped(bh_result);
 	bh_result->b_bdev = inode->i_sb->s_bdev;
 	bh_result->b_blocknr = newblock;
 out2:
@@ -2744,7 +2785,7 @@ out2:
 	return err ? err : allocated;
 }
 
-void ext4_ext_truncate(struct inode * inode, struct page *page)
+void ext4_ext_truncate(struct inode *inode)
 {
 	struct address_space *mapping = inode->i_mapping;
 	struct super_block *sb = inode->i_sb;
@@ -2757,18 +2798,14 @@ void ext4_ext_truncate(struct inode * inode, struct page *page)
 	 */
 	err = ext4_writepage_trans_blocks(inode) + 3;
 	handle = ext4_journal_start(inode, err);
-	if (IS_ERR(handle)) {
-		if (page) {
-			clear_highpage(page);
-			flush_dcache_page(page);
-			unlock_page(page);
-			page_cache_release(page);
-		}
+	if (IS_ERR(handle))
 		return;
-	}
 
-	if (page)
-		ext4_block_truncate_page(handle, page, mapping, inode->i_size);
+	if (inode->i_size & (sb->s_blocksize - 1))
+		ext4_block_truncate_page(handle, mapping, inode->i_size);
+
+	if (ext4_orphan_add(handle, inode))
+		goto out_stop;
 
 	down_write(&EXT4_I(inode)->i_data_sem);
 	ext4_ext_invalidate_cache(inode);
@@ -2780,8 +2817,6 @@ void ext4_ext_truncate(struct inode * inode, struct page *page)
 	 * Probably we need not scan at all,
 	 * because page truncation is enough.
 	 */
-	if (ext4_orphan_add(handle, inode))
-		goto out_stop;
 
 	/* we have to know where to truncate from in crash case */
 	EXT4_I(inode)->i_disksize = inode->i_size;
@@ -2798,6 +2833,7 @@ void ext4_ext_truncate(struct inode * inode, struct page *page)
 		handle->h_sync = 1;
 
 out_stop:
+	up_write(&EXT4_I(inode)->i_data_sem);
 	/*
 	 * If this was a simple ftruncate() and the file will remain alive,
 	 * then we need to clear up the orphan record which we created above.
@@ -2808,7 +2844,6 @@ out_stop:
 	if (inode->i_nlink)
 		ext4_orphan_del(handle, inode);
 
-	up_write(&EXT4_I(inode)->i_data_sem);
 	inode->i_mtime = inode->i_ctime = ext4_current_time(inode);
 	ext4_mark_inode_dirty(handle, inode);
 	ext4_journal_stop(handle);
@@ -2911,7 +2946,7 @@ retry:
 		}
 		ret = ext4_get_blocks_wrap(handle, inode, block,
 					  max_blocks, &map_bh,
-					  EXT4_CREATE_UNINITIALIZED_EXT, 0);
+					  EXT4_CREATE_UNINITIALIZED_EXT, 0, 0);
 		if (ret <= 0) {
 #ifdef EXT4FS_DEBUG
 			WARN_ON(ret <= 0);
diff --git a/fs/ext4/file.c b/fs/ext4/file.c
index 4159be6366a..430eb7978db 100644
--- a/fs/ext4/file.c
+++ b/fs/ext4/file.c
@@ -123,6 +123,23 @@ force_commit:
 	return ret;
 }
 
+static struct vm_operations_struct ext4_file_vm_ops = {
+	.fault		= filemap_fault,
+	.page_mkwrite   = ext4_page_mkwrite,
+};
+
+static int ext4_file_mmap(struct file *file, struct vm_area_struct *vma)
+{
+	struct address_space *mapping = file->f_mapping;
+
+	if (!mapping->a_ops->readpage)
+		return -ENOEXEC;
+	file_accessed(file);
+	vma->vm_ops = &ext4_file_vm_ops;
+	vma->vm_flags |= VM_CAN_NONLINEAR;
+	return 0;
+}
+
 const struct file_operations ext4_file_operations = {
 	.llseek		= generic_file_llseek,
 	.read		= do_sync_read,
@@ -133,7 +150,7 @@ const struct file_operations ext4_file_operations = {
 #ifdef CONFIG_COMPAT
 	.compat_ioctl	= ext4_compat_ioctl,
 #endif
-	.mmap		= generic_file_mmap,
+	.mmap		= ext4_file_mmap,
 	.open		= generic_file_open,
 	.release	= ext4_release_file,
 	.fsync		= ext4_sync_file,
@@ -144,6 +161,7 @@ const struct file_operations ext4_file_operations = {
 const struct inode_operations ext4_file_inode_operations = {
 	.truncate	= ext4_truncate,
 	.setattr	= ext4_setattr,
+	.getattr	= ext4_getattr,
 #ifdef CONFIG_EXT4DEV_FS_XATTR
 	.setxattr	= generic_setxattr,
 	.getxattr	= generic_getxattr,
diff --git a/fs/ext4/fsync.c b/fs/ext4/fsync.c
index 1c8ba48d4f8..a45c3737ad3 100644
--- a/fs/ext4/fsync.c
+++ b/fs/ext4/fsync.c
@@ -27,6 +27,7 @@
 #include <linux/sched.h>
 #include <linux/writeback.h>
 #include <linux/jbd2.h>
+#include <linux/blkdev.h>
 #include "ext4.h"
 #include "ext4_jbd2.h"
 
@@ -45,6 +46,7 @@
 int ext4_sync_file(struct file * file, struct dentry *dentry, int datasync)
 {
 	struct inode *inode = dentry->d_inode;
+	journal_t *journal = EXT4_SB(inode->i_sb)->s_journal;
 	int ret = 0;
 
 	J_ASSERT(ext4_journal_current_handle() == NULL);
@@ -85,6 +87,8 @@ int ext4_sync_file(struct file * file, struct dentry *dentry, int datasync)
 			.nr_to_write = 0, /* sys_fsync did this */
 		};
 		ret = sync_inode(inode, &wbc);
+		if (journal && (journal->j_flags & JBD2_BARRIER))
+			blkdev_issue_flush(inode->i_sb->s_bdev, NULL);
 	}
 out:
 	return ret;
diff --git a/fs/ext4/group.h b/fs/ext4/group.h
index 7eb0604e7ee..c2c0a8d06d0 100644
--- a/fs/ext4/group.h
+++ b/fs/ext4/group.h
@@ -13,7 +13,7 @@ extern __le16 ext4_group_desc_csum(struct ext4_sb_info *sbi, __u32 group,
 				   struct ext4_group_desc *gdp);
 extern int ext4_group_desc_csum_verify(struct ext4_sb_info *sbi, __u32 group,
 				       struct ext4_group_desc *gdp);
-struct buffer_head *read_block_bitmap(struct super_block *sb,
+struct buffer_head *ext4_read_block_bitmap(struct super_block *sb,
 				      ext4_group_t block_group);
 extern unsigned ext4_init_block_bitmap(struct super_block *sb,
 				       struct buffer_head *bh,
diff --git a/fs/ext4/ialloc.c b/fs/ext4/ialloc.c
index c6efbab0c80..a92eb305344 100644
--- a/fs/ext4/ialloc.c
+++ b/fs/ext4/ialloc.c
@@ -157,6 +157,7 @@ void ext4_free_inode (handle_t *handle, struct inode * inode)
 	struct ext4_super_block * es;
 	struct ext4_sb_info *sbi;
 	int fatal = 0, err;
+	ext4_group_t flex_group;
 
 	if (atomic_read(&inode->i_count) > 1) {
 		printk ("ext4_free_inode: inode has count=%d\n",
@@ -232,6 +233,12 @@ void ext4_free_inode (handle_t *handle, struct inode * inode)
 			if (is_directory)
 				percpu_counter_dec(&sbi->s_dirs_counter);
 
+			if (sbi->s_log_groups_per_flex) {
+				flex_group = ext4_flex_group(sbi, block_group);
+				spin_lock(sb_bgl_lock(sbi, flex_group));
+				sbi->s_flex_groups[flex_group].free_inodes++;
+				spin_unlock(sb_bgl_lock(sbi, flex_group));
+			}
 		}
 		BUFFER_TRACE(bh2, "call ext4_journal_dirty_metadata");
 		err = ext4_journal_dirty_metadata(handle, bh2);
@@ -286,6 +293,80 @@ static int find_group_dir(struct super_block *sb, struct inode *parent,
 	return ret;
 }
 
+#define free_block_ratio 10
+
+static int find_group_flex(struct super_block *sb, struct inode *parent,
+			   ext4_group_t *best_group)
+{
+	struct ext4_sb_info *sbi = EXT4_SB(sb);
+	struct ext4_group_desc *desc;
+	struct buffer_head *bh;
+	struct flex_groups *flex_group = sbi->s_flex_groups;
+	ext4_group_t parent_group = EXT4_I(parent)->i_block_group;
+	ext4_group_t parent_fbg_group = ext4_flex_group(sbi, parent_group);
+	ext4_group_t ngroups = sbi->s_groups_count;
+	int flex_size = ext4_flex_bg_size(sbi);
+	ext4_group_t best_flex = parent_fbg_group;
+	int blocks_per_flex = sbi->s_blocks_per_group * flex_size;
+	int flexbg_free_blocks;
+	int flex_freeb_ratio;
+	ext4_group_t n_fbg_groups;
+	ext4_group_t i;
+
+	n_fbg_groups = (sbi->s_groups_count + flex_size - 1) >>
+		sbi->s_log_groups_per_flex;
+
+find_close_to_parent:
+	flexbg_free_blocks = flex_group[best_flex].free_blocks;
+	flex_freeb_ratio = flexbg_free_blocks * 100 / blocks_per_flex;
+	if (flex_group[best_flex].free_inodes &&
+	    flex_freeb_ratio > free_block_ratio)
+		goto found_flexbg;
+
+	if (best_flex && best_flex == parent_fbg_group) {
+		best_flex--;
+		goto find_close_to_parent;
+	}
+
+	for (i = 0; i < n_fbg_groups; i++) {
+		if (i == parent_fbg_group || i == parent_fbg_group - 1)
+			continue;
+
+		flexbg_free_blocks = flex_group[i].free_blocks;
+		flex_freeb_ratio = flexbg_free_blocks * 100 / blocks_per_flex;
+
+		if (flex_freeb_ratio > free_block_ratio &&
+		    flex_group[i].free_inodes) {
+			best_flex = i;
+			goto found_flexbg;
+		}
+
+		if (best_flex < 0 ||
+		    (flex_group[i].free_blocks >
+		     flex_group[best_flex].free_blocks &&
+		     flex_group[i].free_inodes))
+			best_flex = i;
+	}
+
+	if (!flex_group[best_flex].free_inodes ||
+	    !flex_group[best_flex].free_blocks)
+		return -1;
+
+found_flexbg:
+	for (i = best_flex * flex_size; i < ngroups &&
+		     i < (best_flex + 1) * flex_size; i++) {
+		desc = ext4_get_group_desc(sb, i, &bh);
+		if (le16_to_cpu(desc->bg_free_inodes_count)) {
+			*best_group = i;
+			goto out;
+		}
+	}
+
+	return -1;
+out:
+	return 0;
+}
+
 /*
  * Orlov's allocator for directories.
  *
@@ -501,6 +582,7 @@ struct inode *ext4_new_inode(handle_t *handle, struct inode * dir, int mode)
 	struct inode *ret;
 	ext4_group_t i;
 	int free = 0;
+	ext4_group_t flex_group;
 
 	/* Cannot create files in a deleted directory */
 	if (!dir || !dir->i_nlink)
@@ -514,6 +596,12 @@ struct inode *ext4_new_inode(handle_t *handle, struct inode * dir, int mode)
 
 	sbi = EXT4_SB(sb);
 	es = sbi->s_es;
+
+	if (sbi->s_log_groups_per_flex) {
+		ret2 = find_group_flex(sb, dir, &group);
+		goto got_group;
+	}
+
 	if (S_ISDIR(mode)) {
 		if (test_opt (sb, OLDALLOC))
 			ret2 = find_group_dir(sb, dir, &group);
@@ -522,6 +610,7 @@ struct inode *ext4_new_inode(handle_t *handle, struct inode * dir, int mode)
 	} else
 		ret2 = find_group_other(sb, dir, &group);
 
+got_group:
 	err = -ENOSPC;
 	if (ret2 == -1)
 		goto out;
@@ -600,7 +689,7 @@ got:
 	/* We may have to initialize the block bitmap if it isn't already */
 	if (EXT4_HAS_RO_COMPAT_FEATURE(sb, EXT4_FEATURE_RO_COMPAT_GDT_CSUM) &&
 	    gdp->bg_flags & cpu_to_le16(EXT4_BG_BLOCK_UNINIT)) {
-		struct buffer_head *block_bh = read_block_bitmap(sb, group);
+		struct buffer_head *block_bh = ext4_read_block_bitmap(sb, group);
 
 		BUFFER_TRACE(block_bh, "get block bitmap access");
 		err = ext4_journal_get_write_access(handle, block_bh);
@@ -676,6 +765,13 @@ got:
 		percpu_counter_inc(&sbi->s_dirs_counter);
 	sb->s_dirt = 1;
 
+	if (sbi->s_log_groups_per_flex) {
+		flex_group = ext4_flex_group(sbi, group);
+		spin_lock(sb_bgl_lock(sbi, flex_group));
+		sbi->s_flex_groups[flex_group].free_inodes--;
+		spin_unlock(sb_bgl_lock(sbi, flex_group));
+	}
+
 	inode->i_uid = current->fsuid;
 	if (test_opt (sb, GRPID))
 		inode->i_gid = dir->i_gid;
@@ -740,14 +836,10 @@ got:
 		goto fail_free_drop;
 
 	if (test_opt(sb, EXTENTS)) {
-		/* set extent flag only for diretory, file and normal symlink*/
+		/* set extent flag only for directory, file and normal symlink*/
 		if (S_ISDIR(mode) || S_ISREG(mode) || S_ISLNK(mode)) {
 			EXT4_I(inode)->i_flags |= EXT4_EXTENTS_FL;
 			ext4_ext_tree_init(handle, inode);
-			err = ext4_update_incompat_feature(handle, sb,
-					EXT4_FEATURE_INCOMPAT_EXTENTS);
-			if (err)
-				goto fail_free_drop;
 		}
 	}
 
@@ -817,6 +909,14 @@ struct inode *ext4_orphan_get(struct super_block *sb, unsigned long ino)
 	if (IS_ERR(inode))
 		goto iget_failed;
 
+	/*
+	 * If the orphans has i_nlinks > 0 then it should be able to be
+	 * truncated, otherwise it won't be removed from the orphan list
+	 * during processing and an infinite loop will result.
+	 */
+	if (inode->i_nlink && !ext4_can_truncate(inode))
+		goto bad_orphan;
+
 	if (NEXT_ORPHAN(inode) > max_ino)
 		goto bad_orphan;
 	brelse(bitmap_bh);
@@ -838,6 +938,7 @@ bad_orphan:
 		printk(KERN_NOTICE "NEXT_ORPHAN(inode)=%u\n",
 		       NEXT_ORPHAN(inode));
 		printk(KERN_NOTICE "max_ino=%lu\n", max_ino);
+		printk(KERN_NOTICE "i_nlink=%u\n", inode->i_nlink);
 		/* Avoid freeing blocks if we got a bad deleted inode */
 		if (inode->i_nlink == 0)
 			inode->i_blocks = 0;
diff --git a/fs/ext4/inode.c b/fs/ext4/inode.c
index 8d970774641..8ca2763df09 100644
--- a/fs/ext4/inode.c
+++ b/fs/ext4/inode.c
@@ -32,12 +32,23 @@
 #include <linux/string.h>
 #include <linux/buffer_head.h>
 #include <linux/writeback.h>
+#include <linux/pagevec.h>
 #include <linux/mpage.h>
 #include <linux/uio.h>
 #include <linux/bio.h>
 #include "ext4_jbd2.h"
 #include "xattr.h"
 #include "acl.h"
+#include "ext4_extents.h"
+
+static inline int ext4_begin_ordered_truncate(struct inode *inode,
+					      loff_t new_size)
+{
+	return jbd2_journal_begin_ordered_truncate(&EXT4_I(inode)->jinode,
+						   new_size);
+}
+
+static void ext4_invalidatepage(struct page *page, unsigned long offset);
 
 /*
  * Test whether an inode is a fast symlink.
@@ -181,6 +192,8 @@ void ext4_delete_inode (struct inode * inode)
 {
 	handle_t *handle;
 
+	if (ext4_should_order_data(inode))
+		ext4_begin_ordered_truncate(inode, 0);
 	truncate_inode_pages(&inode->i_data, 0);
 
 	if (is_bad_inode(inode))
@@ -508,11 +521,12 @@ static int ext4_blks_to_allocate(Indirect *branch, int k, unsigned long blks,
  *		direct blocks
  */
 static int ext4_alloc_blocks(handle_t *handle, struct inode *inode,
-			ext4_fsblk_t goal, int indirect_blks, int blks,
-			ext4_fsblk_t new_blocks[4], int *err)
+				ext4_lblk_t iblock, ext4_fsblk_t goal,
+				int indirect_blks, int blks,
+				ext4_fsblk_t new_blocks[4], int *err)
 {
 	int target, i;
-	unsigned long count = 0;
+	unsigned long count = 0, blk_allocated = 0;
 	int index = 0;
 	ext4_fsblk_t current_block = 0;
 	int ret = 0;
@@ -525,12 +539,13 @@ static int ext4_alloc_blocks(handle_t *handle, struct inode *inode,
 	 * the first direct block of this branch.  That's the
 	 * minimum number of blocks need to allocate(required)
 	 */
-	target = blks + indirect_blks;
-
-	while (1) {
+	/* first we try to allocate the indirect blocks */
+	target = indirect_blks;
+	while (target > 0) {
 		count = target;
 		/* allocating blocks for indirect blocks and direct blocks */
-		current_block = ext4_new_blocks(handle,inode,goal,&count,err);
+		current_block = ext4_new_meta_blocks(handle, inode,
+							goal, &count, err);
 		if (*err)
 			goto failed_out;
 
@@ -540,16 +555,48 @@ static int ext4_alloc_blocks(handle_t *handle, struct inode *inode,
 			new_blocks[index++] = current_block++;
 			count--;
 		}
-
-		if (count > 0)
+		if (count > 0) {
+			/*
+			 * save the new block number
+			 * for the first direct block
+			 */
+			new_blocks[index] = current_block;
+			printk(KERN_INFO "%s returned more blocks than "
+						"requested\n", __func__);
+			WARN_ON(1);
 			break;
+		}
 	}
 
-	/* save the new block number for the first direct block */
-	new_blocks[index] = current_block;
-
+	target = blks - count ;
+	blk_allocated = count;
+	if (!target)
+		goto allocated;
+	/* Now allocate data blocks */
+	count = target;
+	/* allocating blocks for data blocks */
+	current_block = ext4_new_blocks(handle, inode, iblock,
+						goal, &count, err);
+	if (*err && (target == blks)) {
+		/*
+		 * if the allocation failed and we didn't allocate
+		 * any blocks before
+		 */
+		goto failed_out;
+	}
+	if (!*err) {
+		if (target == blks) {
+		/*
+		 * save the new block number
+		 * for the first direct block
+		 */
+			new_blocks[index] = current_block;
+		}
+		blk_allocated += count;
+	}
+allocated:
 	/* total number of blocks allocated for direct blocks */
-	ret = count;
+	ret = blk_allocated;
 	*err = 0;
 	return ret;
 failed_out:
@@ -584,8 +631,9 @@ failed_out:
  *	as described above and return 0.
  */
 static int ext4_alloc_branch(handle_t *handle, struct inode *inode,
-			int indirect_blks, int *blks, ext4_fsblk_t goal,
-			ext4_lblk_t *offsets, Indirect *branch)
+				ext4_lblk_t iblock, int indirect_blks,
+				int *blks, ext4_fsblk_t goal,
+				ext4_lblk_t *offsets, Indirect *branch)
 {
 	int blocksize = inode->i_sb->s_blocksize;
 	int i, n = 0;
@@ -595,7 +643,7 @@ static int ext4_alloc_branch(handle_t *handle, struct inode *inode,
 	ext4_fsblk_t new_blocks[4];
 	ext4_fsblk_t current_block;
 
-	num = ext4_alloc_blocks(handle, inode, goal, indirect_blks,
+	num = ext4_alloc_blocks(handle, inode, iblock, goal, indirect_blks,
 				*blks, new_blocks, &err);
 	if (err)
 		return err;
@@ -799,6 +847,7 @@ int ext4_get_blocks_handle(handle_t *handle, struct inode *inode,
 	struct ext4_inode_info *ei = EXT4_I(inode);
 	int count = 0;
 	ext4_fsblk_t first_block = 0;
+	loff_t disksize;
 
 
 	J_ASSERT(!(EXT4_I(inode)->i_flags & EXT4_EXTENTS_FL));
@@ -855,8 +904,9 @@ int ext4_get_blocks_handle(handle_t *handle, struct inode *inode,
 	/*
 	 * Block out ext4_truncate while we alter the tree
 	 */
-	err = ext4_alloc_branch(handle, inode, indirect_blks, &count, goal,
-				offsets + (partial - chain), partial);
+	err = ext4_alloc_branch(handle, inode, iblock, indirect_blks,
+					&count, goal,
+					offsets + (partial - chain), partial);
 
 	/*
 	 * The ext4_splice_branch call will free and forget any buffers
@@ -873,8 +923,13 @@ int ext4_get_blocks_handle(handle_t *handle, struct inode *inode,
 	 * protect it if you're about to implement concurrent
 	 * ext4_get_block() -bzzz
 	*/
-	if (!err && extend_disksize && inode->i_size > ei->i_disksize)
-		ei->i_disksize = inode->i_size;
+	if (!err && extend_disksize) {
+		disksize = ((loff_t) iblock + count) << inode->i_blkbits;
+		if (disksize > i_size_read(inode))
+			disksize = i_size_read(inode);
+		if (disksize > ei->i_disksize)
+			ei->i_disksize = disksize;
+	}
 	if (err)
 		goto cleanup;
 
@@ -934,7 +989,7 @@ out:
  */
 int ext4_get_blocks_wrap(handle_t *handle, struct inode *inode, sector_t block,
 			unsigned long max_blocks, struct buffer_head *bh,
-			int create, int extend_disksize)
+			int create, int extend_disksize, int flag)
 {
 	int retval;
 
@@ -975,6 +1030,15 @@ int ext4_get_blocks_wrap(handle_t *handle, struct inode *inode, sector_t block,
 	 * with create == 1 flag.
 	 */
 	down_write((&EXT4_I(inode)->i_data_sem));
+
+	/*
+	 * if the caller is from delayed allocation writeout path
+	 * we have already reserved fs blocks for allocation
+	 * let the underlying get_block() function know to
+	 * avoid double accounting
+	 */
+	if (flag)
+		EXT4_I(inode)->i_delalloc_reserved_flag = 1;
 	/*
 	 * We need to check for EXT4 here because migrate
 	 * could have changed the inode type in between
@@ -996,6 +1060,18 @@ int ext4_get_blocks_wrap(handle_t *handle, struct inode *inode, sector_t block,
 							~EXT4_EXT_MIGRATE;
 		}
 	}
+
+	if (flag) {
+		EXT4_I(inode)->i_delalloc_reserved_flag = 0;
+		/*
+		 * Update reserved blocks/metadata blocks
+		 * after successful block allocation
+		 * which were deferred till now
+		 */
+		if ((retval > 0) && buffer_delay(bh))
+			ext4_da_release_space(inode, retval, 0);
+	}
+
 	up_write((&EXT4_I(inode)->i_data_sem));
 	return retval;
 }
@@ -1021,7 +1097,7 @@ static int ext4_get_block(struct inode *inode, sector_t iblock,
 	}
 
 	ret = ext4_get_blocks_wrap(handle, inode, iblock,
-					max_blocks, bh_result, create, 0);
+					max_blocks, bh_result, create, 0, 0);
 	if (ret > 0) {
 		bh_result->b_size = (ret << inode->i_blkbits);
 		ret = 0;
@@ -1047,7 +1123,7 @@ struct buffer_head *ext4_getblk(handle_t *handle, struct inode *inode,
 	dummy.b_blocknr = -1000;
 	buffer_trace_init(&dummy.b_history);
 	err = ext4_get_blocks_wrap(handle, inode, block, 1,
-					&dummy, create, 1);
+					&dummy, create, 1, 0);
 	/*
 	 * ext4_get_blocks_handle() returns number of blocks
 	 * mapped. 0 in case of a HOLE.
@@ -1203,19 +1279,20 @@ static int ext4_write_begin(struct file *file, struct address_space *mapping,
  	to = from + len;
 
 retry:
- 	page = __grab_cache_page(mapping, index);
- 	if (!page)
- 		return -ENOMEM;
- 	*pagep = page;
-
   	handle = ext4_journal_start(inode, needed_blocks);
   	if (IS_ERR(handle)) {
- 		unlock_page(page);
- 		page_cache_release(page);
   		ret = PTR_ERR(handle);
   		goto out;
 	}
 
+	page = __grab_cache_page(mapping, index);
+	if (!page) {
+		ext4_journal_stop(handle);
+		ret = -ENOMEM;
+		goto out;
+	}
+	*pagep = page;
+
 	ret = block_write_begin(file, mapping, pos, len, flags, pagep, fsdata,
 							ext4_get_block);
 
@@ -1225,8 +1302,8 @@ retry:
 	}
 
 	if (ret) {
-		ext4_journal_stop(handle);
  		unlock_page(page);
+		ext4_journal_stop(handle);
  		page_cache_release(page);
 	}
 
@@ -1236,15 +1313,6 @@ out:
 	return ret;
 }
 
-int ext4_journal_dirty_data(handle_t *handle, struct buffer_head *bh)
-{
-	int err = jbd2_journal_dirty_data(handle, bh);
-	if (err)
-		ext4_journal_abort_handle(__func__, __func__,
-						bh, handle, err);
-	return err;
-}
-
 /* For write_end() in data=journal mode */
 static int write_end_fn(handle_t *handle, struct buffer_head *bh)
 {
@@ -1255,29 +1323,6 @@ static int write_end_fn(handle_t *handle, struct buffer_head *bh)
 }
 
 /*
- * Generic write_end handler for ordered and writeback ext4 journal modes.
- * We can't use generic_write_end, because that unlocks the page and we need to
- * unlock the page after ext4_journal_stop, but ext4_journal_stop must run
- * after block_write_end.
- */
-static int ext4_generic_write_end(struct file *file,
-				struct address_space *mapping,
-				loff_t pos, unsigned len, unsigned copied,
-				struct page *page, void *fsdata)
-{
-	struct inode *inode = file->f_mapping->host;
-
-	copied = block_write_end(file, mapping, pos, len, copied, page, fsdata);
-
-	if (pos+copied > inode->i_size) {
-		i_size_write(inode, pos+copied);
-		mark_inode_dirty(inode);
-	}
-
-	return copied;
-}
-
-/*
  * We need to pick up the new inode size which generic_commit_write gave us
  * `file' can be NULL - eg, when called from page_symlink().
  *
@@ -1290,15 +1335,14 @@ static int ext4_ordered_write_end(struct file *file,
 				struct page *page, void *fsdata)
 {
 	handle_t *handle = ext4_journal_current_handle();
-	struct inode *inode = file->f_mapping->host;
+	struct inode *inode = mapping->host;
 	unsigned from, to;
 	int ret = 0, ret2;
 
 	from = pos & (PAGE_CACHE_SIZE - 1);
 	to = from + len;
 
-	ret = walk_page_buffers(handle, page_buffers(page),
-		from, to, NULL, ext4_journal_dirty_data);
+	ret = ext4_jbd2_file_inode(handle, inode);
 
 	if (ret == 0) {
 		/*
@@ -1311,7 +1355,7 @@ static int ext4_ordered_write_end(struct file *file,
 		new_i_size = pos + copied;
 		if (new_i_size > EXT4_I(inode)->i_disksize)
 			EXT4_I(inode)->i_disksize = new_i_size;
-		ret2 = ext4_generic_write_end(file, mapping, pos, len, copied,
+		ret2 = generic_write_end(file, mapping, pos, len, copied,
 							page, fsdata);
 		copied = ret2;
 		if (ret2 < 0)
@@ -1320,8 +1364,6 @@ static int ext4_ordered_write_end(struct file *file,
 	ret2 = ext4_journal_stop(handle);
 	if (!ret)
 		ret = ret2;
-	unlock_page(page);
-	page_cache_release(page);
 
 	return ret ? ret : copied;
 }
@@ -1332,7 +1374,7 @@ static int ext4_writeback_write_end(struct file *file,
 				struct page *page, void *fsdata)
 {
 	handle_t *handle = ext4_journal_current_handle();
-	struct inode *inode = file->f_mapping->host;
+	struct inode *inode = mapping->host;
 	int ret = 0, ret2;
 	loff_t new_i_size;
 
@@ -1340,7 +1382,7 @@ static int ext4_writeback_write_end(struct file *file,
 	if (new_i_size > EXT4_I(inode)->i_disksize)
 		EXT4_I(inode)->i_disksize = new_i_size;
 
-	ret2 = ext4_generic_write_end(file, mapping, pos, len, copied,
+	ret2 = generic_write_end(file, mapping, pos, len, copied,
 							page, fsdata);
 	copied = ret2;
 	if (ret2 < 0)
@@ -1349,8 +1391,6 @@ static int ext4_writeback_write_end(struct file *file,
 	ret2 = ext4_journal_stop(handle);
 	if (!ret)
 		ret = ret2;
-	unlock_page(page);
-	page_cache_release(page);
 
 	return ret ? ret : copied;
 }
@@ -1389,14 +1429,965 @@ static int ext4_journalled_write_end(struct file *file,
 			ret = ret2;
 	}
 
+	unlock_page(page);
 	ret2 = ext4_journal_stop(handle);
 	if (!ret)
 		ret = ret2;
-	unlock_page(page);
 	page_cache_release(page);
 
 	return ret ? ret : copied;
 }
+/*
+ * Calculate the number of metadata blocks need to reserve
+ * to allocate @blocks for non extent file based file
+ */
+static int ext4_indirect_calc_metadata_amount(struct inode *inode, int blocks)
+{
+	int icap = EXT4_ADDR_PER_BLOCK(inode->i_sb);
+	int ind_blks, dind_blks, tind_blks;
+
+	/* number of new indirect blocks needed */
+	ind_blks = (blocks + icap - 1) / icap;
+
+	dind_blks = (ind_blks + icap - 1) / icap;
+
+	tind_blks = 1;
+
+	return ind_blks + dind_blks + tind_blks;
+}
+
+/*
+ * Calculate the number of metadata blocks need to reserve
+ * to allocate given number of blocks
+ */
+static int ext4_calc_metadata_amount(struct inode *inode, int blocks)
+{
+	if (EXT4_I(inode)->i_flags & EXT4_EXTENTS_FL)
+		return ext4_ext_calc_metadata_amount(inode, blocks);
+
+	return ext4_indirect_calc_metadata_amount(inode, blocks);
+}
+
+static int ext4_da_reserve_space(struct inode *inode, int nrblocks)
+{
+       struct ext4_sb_info *sbi = EXT4_SB(inode->i_sb);
+       unsigned long md_needed, mdblocks, total = 0;
+
+	/*
+	 * recalculate the amount of metadata blocks to reserve
+	 * in order to allocate nrblocks
+	 * worse case is one extent per block
+	 */
+	spin_lock(&EXT4_I(inode)->i_block_reservation_lock);
+	total = EXT4_I(inode)->i_reserved_data_blocks + nrblocks;
+	mdblocks = ext4_calc_metadata_amount(inode, total);
+	BUG_ON(mdblocks < EXT4_I(inode)->i_reserved_meta_blocks);
+
+	md_needed = mdblocks - EXT4_I(inode)->i_reserved_meta_blocks;
+	total = md_needed + nrblocks;
+
+	if (ext4_has_free_blocks(sbi, total) < total) {
+		spin_unlock(&EXT4_I(inode)->i_block_reservation_lock);
+		return -ENOSPC;
+	}
+
+	/* reduce fs free blocks counter */
+	percpu_counter_sub(&sbi->s_freeblocks_counter, total);
+
+	EXT4_I(inode)->i_reserved_data_blocks += nrblocks;
+	EXT4_I(inode)->i_reserved_meta_blocks = mdblocks;
+
+	spin_unlock(&EXT4_I(inode)->i_block_reservation_lock);
+	return 0;       /* success */
+}
+
+void ext4_da_release_space(struct inode *inode, int used, int to_free)
+{
+	struct ext4_sb_info *sbi = EXT4_SB(inode->i_sb);
+	int total, mdb, mdb_free, release;
+
+	spin_lock(&EXT4_I(inode)->i_block_reservation_lock);
+	/* recalculate the number of metablocks still need to be reserved */
+	total = EXT4_I(inode)->i_reserved_data_blocks - used - to_free;
+	mdb = ext4_calc_metadata_amount(inode, total);
+
+	/* figure out how many metablocks to release */
+	BUG_ON(mdb > EXT4_I(inode)->i_reserved_meta_blocks);
+	mdb_free = EXT4_I(inode)->i_reserved_meta_blocks - mdb;
+
+	/* Account for allocated meta_blocks */
+	mdb_free -= EXT4_I(inode)->i_allocated_meta_blocks;
+
+	release = to_free + mdb_free;
+
+	/* update fs free blocks counter for truncate case */
+	percpu_counter_add(&sbi->s_freeblocks_counter, release);
+
+	/* update per-inode reservations */
+	BUG_ON(used + to_free > EXT4_I(inode)->i_reserved_data_blocks);
+	EXT4_I(inode)->i_reserved_data_blocks -= (used + to_free);
+
+	BUG_ON(mdb > EXT4_I(inode)->i_reserved_meta_blocks);
+	EXT4_I(inode)->i_reserved_meta_blocks = mdb;
+	EXT4_I(inode)->i_allocated_meta_blocks = 0;
+	spin_unlock(&EXT4_I(inode)->i_block_reservation_lock);
+}
+
+static void ext4_da_page_release_reservation(struct page *page,
+						unsigned long offset)
+{
+	int to_release = 0;
+	struct buffer_head *head, *bh;
+	unsigned int curr_off = 0;
+
+	head = page_buffers(page);
+	bh = head;
+	do {
+		unsigned int next_off = curr_off + bh->b_size;
+
+		if ((offset <= curr_off) && (buffer_delay(bh))) {
+			to_release++;
+			clear_buffer_delay(bh);
+		}
+		curr_off = next_off;
+	} while ((bh = bh->b_this_page) != head);
+	ext4_da_release_space(page->mapping->host, 0, to_release);
+}
+
+/*
+ * Delayed allocation stuff
+ */
+
+struct mpage_da_data {
+	struct inode *inode;
+	struct buffer_head lbh;			/* extent of blocks */
+	unsigned long first_page, next_page;	/* extent of pages */
+	get_block_t *get_block;
+	struct writeback_control *wbc;
+};
+
+/*
+ * mpage_da_submit_io - walks through extent of pages and try to write
+ * them with __mpage_writepage()
+ *
+ * @mpd->inode: inode
+ * @mpd->first_page: first page of the extent
+ * @mpd->next_page: page after the last page of the extent
+ * @mpd->get_block: the filesystem's block mapper function
+ *
+ * By the time mpage_da_submit_io() is called we expect all blocks
+ * to be allocated. this may be wrong if allocation failed.
+ *
+ * As pages are already locked by write_cache_pages(), we can't use it
+ */
+static int mpage_da_submit_io(struct mpage_da_data *mpd)
+{
+	struct address_space *mapping = mpd->inode->i_mapping;
+	struct mpage_data mpd_pp = {
+		.bio = NULL,
+		.last_block_in_bio = 0,
+		.get_block = mpd->get_block,
+		.use_writepage = 1,
+	};
+	int ret = 0, err, nr_pages, i;
+	unsigned long index, end;
+	struct pagevec pvec;
+
+	BUG_ON(mpd->next_page <= mpd->first_page);
+
+	pagevec_init(&pvec, 0);
+	index = mpd->first_page;
+	end = mpd->next_page - 1;
+
+	while (index <= end) {
+		/* XXX: optimize tail */
+		nr_pages = pagevec_lookup(&pvec, mapping, index, PAGEVEC_SIZE);
+		if (nr_pages == 0)
+			break;
+		for (i = 0; i < nr_pages; i++) {
+			struct page *page = pvec.pages[i];
+
+			index = page->index;
+			if (index > end)
+				break;
+			index++;
+
+			err = __mpage_writepage(page, mpd->wbc, &mpd_pp);
+
+			/*
+			 * In error case, we have to continue because
+			 * remaining pages are still locked
+			 * XXX: unlock and re-dirty them?
+			 */
+			if (ret == 0)
+				ret = err;
+		}
+		pagevec_release(&pvec);
+	}
+	if (mpd_pp.bio)
+		mpage_bio_submit(WRITE, mpd_pp.bio);
+
+	return ret;
+}
+
+/*
+ * mpage_put_bnr_to_bhs - walk blocks and assign them actual numbers
+ *
+ * @mpd->inode - inode to walk through
+ * @exbh->b_blocknr - first block on a disk
+ * @exbh->b_size - amount of space in bytes
+ * @logical - first logical block to start assignment with
+ *
+ * the function goes through all passed space and put actual disk
+ * block numbers into buffer heads, dropping BH_Delay
+ */
+static void mpage_put_bnr_to_bhs(struct mpage_da_data *mpd, sector_t logical,
+				 struct buffer_head *exbh)
+{
+	struct inode *inode = mpd->inode;
+	struct address_space *mapping = inode->i_mapping;
+	int blocks = exbh->b_size >> inode->i_blkbits;
+	sector_t pblock = exbh->b_blocknr, cur_logical;
+	struct buffer_head *head, *bh;
+	unsigned long index, end;
+	struct pagevec pvec;
+	int nr_pages, i;
+
+	index = logical >> (PAGE_CACHE_SHIFT - inode->i_blkbits);
+	end = (logical + blocks - 1) >> (PAGE_CACHE_SHIFT - inode->i_blkbits);
+	cur_logical = index << (PAGE_CACHE_SHIFT - inode->i_blkbits);
+
+	pagevec_init(&pvec, 0);
+
+	while (index <= end) {
+		/* XXX: optimize tail */
+		nr_pages = pagevec_lookup(&pvec, mapping, index, PAGEVEC_SIZE);
+		if (nr_pages == 0)
+			break;
+		for (i = 0; i < nr_pages; i++) {
+			struct page *page = pvec.pages[i];
+
+			index = page->index;
+			if (index > end)
+				break;
+			index++;
+
+			BUG_ON(!PageLocked(page));
+			BUG_ON(PageWriteback(page));
+			BUG_ON(!page_has_buffers(page));
+
+			bh = page_buffers(page);
+			head = bh;
+
+			/* skip blocks out of the range */
+			do {
+				if (cur_logical >= logical)
+					break;
+				cur_logical++;
+			} while ((bh = bh->b_this_page) != head);
+
+			do {
+				if (cur_logical >= logical + blocks)
+					break;
+				if (buffer_delay(bh)) {
+					bh->b_blocknr = pblock;
+					clear_buffer_delay(bh);
+				} else if (buffer_mapped(bh))
+					BUG_ON(bh->b_blocknr != pblock);
+
+				cur_logical++;
+				pblock++;
+			} while ((bh = bh->b_this_page) != head);
+		}
+		pagevec_release(&pvec);
+	}
+}
+
+
+/*
+ * __unmap_underlying_blocks - just a helper function to unmap
+ * set of blocks described by @bh
+ */
+static inline void __unmap_underlying_blocks(struct inode *inode,
+					     struct buffer_head *bh)
+{
+	struct block_device *bdev = inode->i_sb->s_bdev;
+	int blocks, i;
+
+	blocks = bh->b_size >> inode->i_blkbits;
+	for (i = 0; i < blocks; i++)
+		unmap_underlying_metadata(bdev, bh->b_blocknr + i);
+}
+
+/*
+ * mpage_da_map_blocks - go through given space
+ *
+ * @mpd->lbh - bh describing space
+ * @mpd->get_block - the filesystem's block mapper function
+ *
+ * The function skips space we know is already mapped to disk blocks.
+ *
+ * The function ignores errors ->get_block() returns, thus real
+ * error handling is postponed to __mpage_writepage()
+ */
+static void mpage_da_map_blocks(struct mpage_da_data *mpd)
+{
+	struct buffer_head *lbh = &mpd->lbh;
+	int err = 0, remain = lbh->b_size;
+	sector_t next = lbh->b_blocknr;
+	struct buffer_head new;
+
+	/*
+	 * We consider only non-mapped and non-allocated blocks
+	 */
+	if (buffer_mapped(lbh) && !buffer_delay(lbh))
+		return;
+
+	while (remain) {
+		new.b_state = lbh->b_state;
+		new.b_blocknr = 0;
+		new.b_size = remain;
+		err = mpd->get_block(mpd->inode, next, &new, 1);
+		if (err) {
+			/*
+			 * Rather than implement own error handling
+			 * here, we just leave remaining blocks
+			 * unallocated and try again with ->writepage()
+			 */
+			break;
+		}
+		BUG_ON(new.b_size == 0);
+
+		if (buffer_new(&new))
+			__unmap_underlying_blocks(mpd->inode, &new);
+
+		/*
+		 * If blocks are delayed marked, we need to
+		 * put actual blocknr and drop delayed bit
+		 */
+		if (buffer_delay(lbh))
+			mpage_put_bnr_to_bhs(mpd, next, &new);
+
+		/* go for the remaining blocks */
+		next += new.b_size >> mpd->inode->i_blkbits;
+		remain -= new.b_size;
+	}
+}
+
+#define BH_FLAGS ((1 << BH_Uptodate) | (1 << BH_Mapped) | (1 << BH_Delay))
+
+/*
+ * mpage_add_bh_to_extent - try to add one more block to extent of blocks
+ *
+ * @mpd->lbh - extent of blocks
+ * @logical - logical number of the block in the file
+ * @bh - bh of the block (used to access block's state)
+ *
+ * the function is used to collect contig. blocks in same state
+ */
+static void mpage_add_bh_to_extent(struct mpage_da_data *mpd,
+				   sector_t logical, struct buffer_head *bh)
+{
+	struct buffer_head *lbh = &mpd->lbh;
+	sector_t next;
+
+	next = lbh->b_blocknr + (lbh->b_size >> mpd->inode->i_blkbits);
+
+	/*
+	 * First block in the extent
+	 */
+	if (lbh->b_size == 0) {
+		lbh->b_blocknr = logical;
+		lbh->b_size = bh->b_size;
+		lbh->b_state = bh->b_state & BH_FLAGS;
+		return;
+	}
+
+	/*
+	 * Can we merge the block to our big extent?
+	 */
+	if (logical == next && (bh->b_state & BH_FLAGS) == lbh->b_state) {
+		lbh->b_size += bh->b_size;
+		return;
+	}
+
+	/*
+	 * We couldn't merge the block to our extent, so we
+	 * need to flush current  extent and start new one
+	 */
+	mpage_da_map_blocks(mpd);
+
+	/*
+	 * Now start a new extent
+	 */
+	lbh->b_size = bh->b_size;
+	lbh->b_state = bh->b_state & BH_FLAGS;
+	lbh->b_blocknr = logical;
+}
+
+/*
+ * __mpage_da_writepage - finds extent of pages and blocks
+ *
+ * @page: page to consider
+ * @wbc: not used, we just follow rules
+ * @data: context
+ *
+ * The function finds extents of pages and scan them for all blocks.
+ */
+static int __mpage_da_writepage(struct page *page,
+				struct writeback_control *wbc, void *data)
+{
+	struct mpage_da_data *mpd = data;
+	struct inode *inode = mpd->inode;
+	struct buffer_head *bh, *head, fake;
+	sector_t logical;
+
+	/*
+	 * Can we merge this page to current extent?
+	 */
+	if (mpd->next_page != page->index) {
+		/*
+		 * Nope, we can't. So, we map non-allocated blocks
+		 * and start IO on them using __mpage_writepage()
+		 */
+		if (mpd->next_page != mpd->first_page) {
+			mpage_da_map_blocks(mpd);
+			mpage_da_submit_io(mpd);
+		}
+
+		/*
+		 * Start next extent of pages ...
+		 */
+		mpd->first_page = page->index;
+
+		/*
+		 * ... and blocks
+		 */
+		mpd->lbh.b_size = 0;
+		mpd->lbh.b_state = 0;
+		mpd->lbh.b_blocknr = 0;
+	}
+
+	mpd->next_page = page->index + 1;
+	logical = (sector_t) page->index <<
+		  (PAGE_CACHE_SHIFT - inode->i_blkbits);
+
+	if (!page_has_buffers(page)) {
+		/*
+		 * There is no attached buffer heads yet (mmap?)
+		 * we treat the page asfull of dirty blocks
+		 */
+		bh = &fake;
+		bh->b_size = PAGE_CACHE_SIZE;
+		bh->b_state = 0;
+		set_buffer_dirty(bh);
+		set_buffer_uptodate(bh);
+		mpage_add_bh_to_extent(mpd, logical, bh);
+	} else {
+		/*
+		 * Page with regular buffer heads, just add all dirty ones
+		 */
+		head = page_buffers(page);
+		bh = head;
+		do {
+			BUG_ON(buffer_locked(bh));
+			if (buffer_dirty(bh))
+				mpage_add_bh_to_extent(mpd, logical, bh);
+			logical++;
+		} while ((bh = bh->b_this_page) != head);
+	}
+
+	return 0;
+}
+
+/*
+ * mpage_da_writepages - walk the list of dirty pages of the given
+ * address space, allocates non-allocated blocks, maps newly-allocated
+ * blocks to existing bhs and issue IO them
+ *
+ * @mapping: address space structure to write
+ * @wbc: subtract the number of written pages from *@wbc->nr_to_write
+ * @get_block: the filesystem's block mapper function.
+ *
+ * This is a library function, which implements the writepages()
+ * address_space_operation.
+ *
+ * In order to avoid duplication of logic that deals with partial pages,
+ * multiple bio per page, etc, we find non-allocated blocks, allocate
+ * them with minimal calls to ->get_block() and re-use __mpage_writepage()
+ *
+ * It's important that we call __mpage_writepage() only once for each
+ * involved page, otherwise we'd have to implement more complicated logic
+ * to deal with pages w/o PG_lock or w/ PG_writeback and so on.
+ *
+ * See comments to mpage_writepages()
+ */
+static int mpage_da_writepages(struct address_space *mapping,
+			       struct writeback_control *wbc,
+			       get_block_t get_block)
+{
+	struct mpage_da_data mpd;
+	int ret;
+
+	if (!get_block)
+		return generic_writepages(mapping, wbc);
+
+	mpd.wbc = wbc;
+	mpd.inode = mapping->host;
+	mpd.lbh.b_size = 0;
+	mpd.lbh.b_state = 0;
+	mpd.lbh.b_blocknr = 0;
+	mpd.first_page = 0;
+	mpd.next_page = 0;
+	mpd.get_block = get_block;
+
+	ret = write_cache_pages(mapping, wbc, __mpage_da_writepage, &mpd);
+
+	/*
+	 * Handle last extent of pages
+	 */
+	if (mpd.next_page != mpd.first_page) {
+		mpage_da_map_blocks(&mpd);
+		mpage_da_submit_io(&mpd);
+	}
+
+	return ret;
+}
+
+/*
+ * this is a special callback for ->write_begin() only
+ * it's intention is to return mapped block or reserve space
+ */
+static int ext4_da_get_block_prep(struct inode *inode, sector_t iblock,
+				  struct buffer_head *bh_result, int create)
+{
+	int ret = 0;
+
+	BUG_ON(create == 0);
+	BUG_ON(bh_result->b_size != inode->i_sb->s_blocksize);
+
+	/*
+	 * first, we need to know whether the block is allocated already
+	 * preallocated blocks are unmapped but should treated
+	 * the same as allocated blocks.
+	 */
+	ret = ext4_get_blocks_wrap(NULL, inode, iblock, 1,  bh_result, 0, 0, 0);
+	if ((ret == 0) && !buffer_delay(bh_result)) {
+		/* the block isn't (pre)allocated yet, let's reserve space */
+		/*
+		 * XXX: __block_prepare_write() unmaps passed block,
+		 * is it OK?
+		 */
+		ret = ext4_da_reserve_space(inode, 1);
+		if (ret)
+			/* not enough space to reserve */
+			return ret;
+
+		map_bh(bh_result, inode->i_sb, 0);
+		set_buffer_new(bh_result);
+		set_buffer_delay(bh_result);
+	} else if (ret > 0) {
+		bh_result->b_size = (ret << inode->i_blkbits);
+		ret = 0;
+	}
+
+	return ret;
+}
+#define		EXT4_DELALLOC_RSVED	1
+static int ext4_da_get_block_write(struct inode *inode, sector_t iblock,
+				   struct buffer_head *bh_result, int create)
+{
+	int ret;
+	unsigned max_blocks = bh_result->b_size >> inode->i_blkbits;
+	loff_t disksize = EXT4_I(inode)->i_disksize;
+	handle_t *handle = NULL;
+
+	handle = ext4_journal_current_handle();
+	if (!handle) {
+		ret = ext4_get_blocks_wrap(handle, inode, iblock, max_blocks,
+				   bh_result, 0, 0, 0);
+		BUG_ON(!ret);
+	} else {
+		ret = ext4_get_blocks_wrap(handle, inode, iblock, max_blocks,
+				   bh_result, create, 0, EXT4_DELALLOC_RSVED);
+	}
+
+	if (ret > 0) {
+		bh_result->b_size = (ret << inode->i_blkbits);
+
+		/*
+		 * Update on-disk size along with block allocation
+		 * we don't use 'extend_disksize' as size may change
+		 * within already allocated block -bzzz
+		 */
+		disksize = ((loff_t) iblock + ret) << inode->i_blkbits;
+		if (disksize > i_size_read(inode))
+			disksize = i_size_read(inode);
+		if (disksize > EXT4_I(inode)->i_disksize) {
+			/*
+			 * XXX: replace with spinlock if seen contended -bzzz
+			 */
+			down_write(&EXT4_I(inode)->i_data_sem);
+			if (disksize > EXT4_I(inode)->i_disksize)
+				EXT4_I(inode)->i_disksize = disksize;
+			up_write(&EXT4_I(inode)->i_data_sem);
+
+			if (EXT4_I(inode)->i_disksize == disksize) {
+				ret = ext4_mark_inode_dirty(handle, inode);
+				return ret;
+			}
+		}
+		ret = 0;
+	}
+	return ret;
+}
+
+static int ext4_bh_unmapped_or_delay(handle_t *handle, struct buffer_head *bh)
+{
+	/*
+	 * unmapped buffer is possible for holes.
+	 * delay buffer is possible with delayed allocation
+	 */
+	return ((!buffer_mapped(bh) || buffer_delay(bh)) && buffer_dirty(bh));
+}
+
+static int ext4_normal_get_block_write(struct inode *inode, sector_t iblock,
+				   struct buffer_head *bh_result, int create)
+{
+	int ret = 0;
+	unsigned max_blocks = bh_result->b_size >> inode->i_blkbits;
+
+	/*
+	 * we don't want to do block allocation in writepage
+	 * so call get_block_wrap with create = 0
+	 */
+	ret = ext4_get_blocks_wrap(NULL, inode, iblock, max_blocks,
+				   bh_result, 0, 0, 0);
+	if (ret > 0) {
+		bh_result->b_size = (ret << inode->i_blkbits);
+		ret = 0;
+	}
+	return ret;
+}
+
+/*
+ * get called vi ext4_da_writepages after taking page lock (have journal handle)
+ * get called via journal_submit_inode_data_buffers (no journal handle)
+ * get called via shrink_page_list via pdflush (no journal handle)
+ * or grab_page_cache when doing write_begin (have journal handle)
+ */
+static int ext4_da_writepage(struct page *page,
+				struct writeback_control *wbc)
+{
+	int ret = 0;
+	loff_t size;
+	unsigned long len;
+	struct buffer_head *page_bufs;
+	struct inode *inode = page->mapping->host;
+
+	size = i_size_read(inode);
+	if (page->index == size >> PAGE_CACHE_SHIFT)
+		len = size & ~PAGE_CACHE_MASK;
+	else
+		len = PAGE_CACHE_SIZE;
+
+	if (page_has_buffers(page)) {
+		page_bufs = page_buffers(page);
+		if (walk_page_buffers(NULL, page_bufs, 0, len, NULL,
+					ext4_bh_unmapped_or_delay)) {
+			/*
+			 * We don't want to do  block allocation
+			 * So redirty the page and return
+			 * We may reach here when we do a journal commit
+			 * via journal_submit_inode_data_buffers.
+			 * If we don't have mapping block we just ignore
+			 * them. We can also reach here via shrink_page_list
+			 */
+			redirty_page_for_writepage(wbc, page);
+			unlock_page(page);
+			return 0;
+		}
+	} else {
+		/*
+		 * The test for page_has_buffers() is subtle:
+		 * We know the page is dirty but it lost buffers. That means
+		 * that at some moment in time after write_begin()/write_end()
+		 * has been called all buffers have been clean and thus they
+		 * must have been written at least once. So they are all
+		 * mapped and we can happily proceed with mapping them
+		 * and writing the page.
+		 *
+		 * Try to initialize the buffer_heads and check whether
+		 * all are mapped and non delay. We don't want to
+		 * do block allocation here.
+		 */
+		ret = block_prepare_write(page, 0, PAGE_CACHE_SIZE,
+						ext4_normal_get_block_write);
+		if (!ret) {
+			page_bufs = page_buffers(page);
+			/* check whether all are mapped and non delay */
+			if (walk_page_buffers(NULL, page_bufs, 0, len, NULL,
+						ext4_bh_unmapped_or_delay)) {
+				redirty_page_for_writepage(wbc, page);
+				unlock_page(page);
+				return 0;
+			}
+		} else {
+			/*
+			 * We can't do block allocation here
+			 * so just redity the page and unlock
+			 * and return
+			 */
+			redirty_page_for_writepage(wbc, page);
+			unlock_page(page);
+			return 0;
+		}
+	}
+
+	if (test_opt(inode->i_sb, NOBH) && ext4_should_writeback_data(inode))
+		ret = nobh_writepage(page, ext4_normal_get_block_write, wbc);
+	else
+		ret = block_write_full_page(page,
+						ext4_normal_get_block_write,
+						wbc);
+
+	return ret;
+}
+
+/*
+ * For now just follow the DIO way to estimate the max credits
+ * needed to write out EXT4_MAX_WRITEBACK_PAGES.
+ * todo: need to calculate the max credits need for
+ * extent based files, currently the DIO credits is based on
+ * indirect-blocks mapping way.
+ *
+ * Probably should have a generic way to calculate credits
+ * for DIO, writepages, and truncate
+ */
+#define EXT4_MAX_WRITEBACK_PAGES      DIO_MAX_BLOCKS
+#define EXT4_MAX_WRITEBACK_CREDITS    DIO_CREDITS
+
+static int ext4_da_writepages(struct address_space *mapping,
+				struct writeback_control *wbc)
+{
+	struct inode *inode = mapping->host;
+	handle_t *handle = NULL;
+	int needed_blocks;
+	int ret = 0;
+	long to_write;
+	loff_t range_start = 0;
+
+	/*
+	 * No pages to write? This is mainly a kludge to avoid starting
+	 * a transaction for special inodes like journal inode on last iput()
+	 * because that could violate lock ordering on umount
+	 */
+	if (!mapping->nrpages)
+		return 0;
+
+	/*
+	 * Estimate the worse case needed credits to write out
+	 * EXT4_MAX_BUF_BLOCKS pages
+	 */
+	needed_blocks = EXT4_MAX_WRITEBACK_CREDITS;
+
+	to_write = wbc->nr_to_write;
+	if (!wbc->range_cyclic) {
+		/*
+		 * If range_cyclic is not set force range_cont
+		 * and save the old writeback_index
+		 */
+		wbc->range_cont = 1;
+		range_start =  wbc->range_start;
+	}
+
+	while (!ret && to_write) {
+		/* start a new transaction*/
+		handle = ext4_journal_start(inode, needed_blocks);
+		if (IS_ERR(handle)) {
+			ret = PTR_ERR(handle);
+			goto out_writepages;
+		}
+		if (ext4_should_order_data(inode)) {
+			/*
+			 * With ordered mode we need to add
+			 * the inode to the journal handle
+			 * when we do block allocation.
+			 */
+			ret = ext4_jbd2_file_inode(handle, inode);
+			if (ret) {
+				ext4_journal_stop(handle);
+				goto out_writepages;
+			}
+
+		}
+		/*
+		 * set the max dirty pages could be write at a time
+		 * to fit into the reserved transaction credits
+		 */
+		if (wbc->nr_to_write > EXT4_MAX_WRITEBACK_PAGES)
+			wbc->nr_to_write = EXT4_MAX_WRITEBACK_PAGES;
+
+		to_write -= wbc->nr_to_write;
+		ret = mpage_da_writepages(mapping, wbc,
+						ext4_da_get_block_write);
+		ext4_journal_stop(handle);
+		if (wbc->nr_to_write) {
+			/*
+			 * There is no more writeout needed
+			 * or we requested for a noblocking writeout
+			 * and we found the device congested
+			 */
+			to_write += wbc->nr_to_write;
+			break;
+		}
+		wbc->nr_to_write = to_write;
+	}
+
+out_writepages:
+	wbc->nr_to_write = to_write;
+	if (range_start)
+		wbc->range_start = range_start;
+	return ret;
+}
+
+static int ext4_da_write_begin(struct file *file, struct address_space *mapping,
+				loff_t pos, unsigned len, unsigned flags,
+				struct page **pagep, void **fsdata)
+{
+	int ret, retries = 0;
+	struct page *page;
+	pgoff_t index;
+	unsigned from, to;
+	struct inode *inode = mapping->host;
+	handle_t *handle;
+
+	index = pos >> PAGE_CACHE_SHIFT;
+	from = pos & (PAGE_CACHE_SIZE - 1);
+	to = from + len;
+
+retry:
+	/*
+	 * With delayed allocation, we don't log the i_disksize update
+	 * if there is delayed block allocation. But we still need
+	 * to journalling the i_disksize update if writes to the end
+	 * of file which has an already mapped buffer.
+	 */
+	handle = ext4_journal_start(inode, 1);
+	if (IS_ERR(handle)) {
+		ret = PTR_ERR(handle);
+		goto out;
+	}
+
+	page = __grab_cache_page(mapping, index);
+	if (!page)
+		return -ENOMEM;
+	*pagep = page;
+
+	ret = block_write_begin(file, mapping, pos, len, flags, pagep, fsdata,
+							ext4_da_get_block_prep);
+	if (ret < 0) {
+		unlock_page(page);
+		ext4_journal_stop(handle);
+		page_cache_release(page);
+	}
+
+	if (ret == -ENOSPC && ext4_should_retry_alloc(inode->i_sb, &retries))
+		goto retry;
+out:
+	return ret;
+}
+
+/*
+ * Check if we should update i_disksize
+ * when write to the end of file but not require block allocation
+ */
+static int ext4_da_should_update_i_disksize(struct page *page,
+					 unsigned long offset)
+{
+	struct buffer_head *bh;
+	struct inode *inode = page->mapping->host;
+	unsigned int idx;
+	int i;
+
+	bh = page_buffers(page);
+	idx = offset >> inode->i_blkbits;
+
+	for (i=0; i < idx; i++)
+		bh = bh->b_this_page;
+
+	if (!buffer_mapped(bh) || (buffer_delay(bh)))
+		return 0;
+	return 1;
+}
+
+static int ext4_da_write_end(struct file *file,
+				struct address_space *mapping,
+				loff_t pos, unsigned len, unsigned copied,
+				struct page *page, void *fsdata)
+{
+	struct inode *inode = mapping->host;
+	int ret = 0, ret2;
+	handle_t *handle = ext4_journal_current_handle();
+	loff_t new_i_size;
+	unsigned long start, end;
+
+	start = pos & (PAGE_CACHE_SIZE - 1);
+	end = start + copied -1;
+
+	/*
+	 * generic_write_end() will run mark_inode_dirty() if i_size
+	 * changes.  So let's piggyback the i_disksize mark_inode_dirty
+	 * into that.
+	 */
+
+	new_i_size = pos + copied;
+	if (new_i_size > EXT4_I(inode)->i_disksize) {
+		if (ext4_da_should_update_i_disksize(page, end)) {
+			down_write(&EXT4_I(inode)->i_data_sem);
+			if (new_i_size > EXT4_I(inode)->i_disksize) {
+				/*
+				 * Updating i_disksize when extending file
+				 * without needing block allocation
+				 */
+				if (ext4_should_order_data(inode))
+					ret = ext4_jbd2_file_inode(handle,
+								   inode);
+
+				EXT4_I(inode)->i_disksize = new_i_size;
+			}
+			up_write(&EXT4_I(inode)->i_data_sem);
+		}
+	}
+	ret2 = generic_write_end(file, mapping, pos, len, copied,
+							page, fsdata);
+	copied = ret2;
+	if (ret2 < 0)
+		ret = ret2;
+	ret2 = ext4_journal_stop(handle);
+	if (!ret)
+		ret = ret2;
+
+	return ret ? ret : copied;
+}
+
+static void ext4_da_invalidatepage(struct page *page, unsigned long offset)
+{
+	/*
+	 * Drop reserved blocks
+	 */
+	BUG_ON(!PageLocked(page));
+	if (!page_has_buffers(page))
+		goto out;
+
+	ext4_da_page_release_reservation(page, offset);
+
+out:
+	ext4_invalidatepage(page, offset);
+
+	return;
+}
+
 
 /*
  * bmap() is special.  It gets used by applications such as lilo and by
@@ -1418,6 +2409,16 @@ static sector_t ext4_bmap(struct address_space *mapping, sector_t block)
 	journal_t *journal;
 	int err;
 
+	if (mapping_tagged(mapping, PAGECACHE_TAG_DIRTY) &&
+			test_opt(inode->i_sb, DELALLOC)) {
+		/*
+		 * With delalloc we want to sync the file
+		 * so that we can make sure we allocate
+		 * blocks for file
+		 */
+		filemap_write_and_wait(mapping);
+	}
+
 	if (EXT4_I(inode)->i_state & EXT4_STATE_JDATA) {
 		/*
 		 * This is a REALLY heavyweight approach, but the use of
@@ -1462,21 +2463,17 @@ static int bput_one(handle_t *handle, struct buffer_head *bh)
 	return 0;
 }
 
-static int jbd2_journal_dirty_data_fn(handle_t *handle, struct buffer_head *bh)
-{
-	if (buffer_mapped(bh))
-		return ext4_journal_dirty_data(handle, bh);
-	return 0;
-}
-
 /*
- * Note that we always start a transaction even if we're not journalling
- * data.  This is to preserve ordering: any hole instantiation within
- * __block_write_full_page -> ext4_get_block() should be journalled
- * along with the data so we don't crash and then get metadata which
- * refers to old data.
+ * Note that we don't need to start a transaction unless we're journaling data
+ * because we should have holes filled from ext4_page_mkwrite(). We even don't
+ * need to file the inode to the transaction's list in ordered mode because if
+ * we are writing back data added by write(), the inode is already there and if
+ * we are writing back data modified via mmap(), noone guarantees in which
+ * transaction the data will hit the disk. In case we are journaling data, we
+ * cannot start transaction directly because transaction start ranks above page
+ * lock so we have to do some magic.
  *
- * In all journalling modes block_write_full_page() will start the I/O.
+ * In all journaling modes block_write_full_page() will start the I/O.
  *
  * Problem:
  *
@@ -1518,105 +2515,103 @@ static int jbd2_journal_dirty_data_fn(handle_t *handle, struct buffer_head *bh)
  * disastrous.  Any write() or metadata operation will sync the fs for
  * us.
  *
- * AKPM2: if all the page's buffers are mapped to disk and !data=journal,
- * we don't need to open a transaction here.
  */
-static int ext4_ordered_writepage(struct page *page,
+static int __ext4_normal_writepage(struct page *page,
 				struct writeback_control *wbc)
 {
 	struct inode *inode = page->mapping->host;
-	struct buffer_head *page_bufs;
-	handle_t *handle = NULL;
-	int ret = 0;
-	int err;
-
-	J_ASSERT(PageLocked(page));
-
-	/*
-	 * We give up here if we're reentered, because it might be for a
-	 * different filesystem.
-	 */
-	if (ext4_journal_current_handle())
-		goto out_fail;
 
-	handle = ext4_journal_start(inode, ext4_writepage_trans_blocks(inode));
+	if (test_opt(inode->i_sb, NOBH))
+		return nobh_writepage(page,
+					ext4_normal_get_block_write, wbc);
+	else
+		return block_write_full_page(page,
+						ext4_normal_get_block_write,
+						wbc);
+}
 
-	if (IS_ERR(handle)) {
-		ret = PTR_ERR(handle);
-		goto out_fail;
-	}
+static int ext4_normal_writepage(struct page *page,
+				struct writeback_control *wbc)
+{
+	struct inode *inode = page->mapping->host;
+	loff_t size = i_size_read(inode);
+	loff_t len;
 
-	if (!page_has_buffers(page)) {
-		create_empty_buffers(page, inode->i_sb->s_blocksize,
-				(1 << BH_Dirty)|(1 << BH_Uptodate));
+	J_ASSERT(PageLocked(page));
+	if (page->index == size >> PAGE_CACHE_SHIFT)
+		len = size & ~PAGE_CACHE_MASK;
+	else
+		len = PAGE_CACHE_SIZE;
+
+	if (page_has_buffers(page)) {
+		/* if page has buffers it should all be mapped
+		 * and allocated. If there are not buffers attached
+		 * to the page we know the page is dirty but it lost
+		 * buffers. That means that at some moment in time
+		 * after write_begin() / write_end() has been called
+		 * all buffers have been clean and thus they must have been
+		 * written at least once. So they are all mapped and we can
+		 * happily proceed with mapping them and writing the page.
+		 */
+		BUG_ON(walk_page_buffers(NULL, page_buffers(page), 0, len, NULL,
+					ext4_bh_unmapped_or_delay));
 	}
-	page_bufs = page_buffers(page);
-	walk_page_buffers(handle, page_bufs, 0,
-			PAGE_CACHE_SIZE, NULL, bget_one);
-
-	ret = block_write_full_page(page, ext4_get_block, wbc);
 
-	/*
-	 * The page can become unlocked at any point now, and
-	 * truncate can then come in and change things.  So we
-	 * can't touch *page from now on.  But *page_bufs is
-	 * safe due to elevated refcount.
-	 */
+	if (!ext4_journal_current_handle())
+		return __ext4_normal_writepage(page, wbc);
 
-	/*
-	 * And attach them to the current transaction.  But only if
-	 * block_write_full_page() succeeded.  Otherwise they are unmapped,
-	 * and generally junk.
-	 */
-	if (ret == 0) {
-		err = walk_page_buffers(handle, page_bufs, 0, PAGE_CACHE_SIZE,
-					NULL, jbd2_journal_dirty_data_fn);
-		if (!ret)
-			ret = err;
-	}
-	walk_page_buffers(handle, page_bufs, 0,
-			PAGE_CACHE_SIZE, NULL, bput_one);
-	err = ext4_journal_stop(handle);
-	if (!ret)
-		ret = err;
-	return ret;
-
-out_fail:
 	redirty_page_for_writepage(wbc, page);
 	unlock_page(page);
-	return ret;
+	return 0;
 }
 
-static int ext4_writeback_writepage(struct page *page,
+static int __ext4_journalled_writepage(struct page *page,
 				struct writeback_control *wbc)
 {
-	struct inode *inode = page->mapping->host;
+	struct address_space *mapping = page->mapping;
+	struct inode *inode = mapping->host;
+	struct buffer_head *page_bufs;
 	handle_t *handle = NULL;
 	int ret = 0;
 	int err;
 
-	if (ext4_journal_current_handle())
-		goto out_fail;
+	ret = block_prepare_write(page, 0, PAGE_CACHE_SIZE,
+					ext4_normal_get_block_write);
+	if (ret != 0)
+		goto out_unlock;
+
+	page_bufs = page_buffers(page);
+	walk_page_buffers(handle, page_bufs, 0, PAGE_CACHE_SIZE, NULL,
+								bget_one);
+	/* As soon as we unlock the page, it can go away, but we have
+	 * references to buffers so we are safe */
+	unlock_page(page);
 
 	handle = ext4_journal_start(inode, ext4_writepage_trans_blocks(inode));
 	if (IS_ERR(handle)) {
 		ret = PTR_ERR(handle);
-		goto out_fail;
+		goto out;
 	}
 
-	if (test_opt(inode->i_sb, NOBH) && ext4_should_writeback_data(inode))
-		ret = nobh_writepage(page, ext4_get_block, wbc);
-	else
-		ret = block_write_full_page(page, ext4_get_block, wbc);
+	ret = walk_page_buffers(handle, page_bufs, 0,
+			PAGE_CACHE_SIZE, NULL, do_journal_get_write_access);
 
+	err = walk_page_buffers(handle, page_bufs, 0,
+				PAGE_CACHE_SIZE, NULL, write_end_fn);
+	if (ret == 0)
+		ret = err;
 	err = ext4_journal_stop(handle);
 	if (!ret)
 		ret = err;
-	return ret;
 
-out_fail:
-	redirty_page_for_writepage(wbc, page);
+	walk_page_buffers(handle, page_bufs, 0,
+				PAGE_CACHE_SIZE, NULL, bput_one);
+	EXT4_I(inode)->i_state |= EXT4_STATE_JDATA;
+	goto out;
+
+out_unlock:
 	unlock_page(page);
+out:
 	return ret;
 }
 
@@ -1624,59 +2619,53 @@ static int ext4_journalled_writepage(struct page *page,
 				struct writeback_control *wbc)
 {
 	struct inode *inode = page->mapping->host;
-	handle_t *handle = NULL;
-	int ret = 0;
-	int err;
+	loff_t size = i_size_read(inode);
+	loff_t len;
 
-	if (ext4_journal_current_handle())
-		goto no_write;
+	J_ASSERT(PageLocked(page));
+	if (page->index == size >> PAGE_CACHE_SHIFT)
+		len = size & ~PAGE_CACHE_MASK;
+	else
+		len = PAGE_CACHE_SIZE;
+
+	if (page_has_buffers(page)) {
+		/* if page has buffers it should all be mapped
+		 * and allocated. If there are not buffers attached
+		 * to the page we know the page is dirty but it lost
+		 * buffers. That means that at some moment in time
+		 * after write_begin() / write_end() has been called
+		 * all buffers have been clean and thus they must have been
+		 * written at least once. So they are all mapped and we can
+		 * happily proceed with mapping them and writing the page.
+		 */
+		BUG_ON(walk_page_buffers(NULL, page_buffers(page), 0, len, NULL,
+					ext4_bh_unmapped_or_delay));
+	}
 
-	handle = ext4_journal_start(inode, ext4_writepage_trans_blocks(inode));
-	if (IS_ERR(handle)) {
-		ret = PTR_ERR(handle);
+	if (ext4_journal_current_handle())
 		goto no_write;
-	}
 
-	if (!page_has_buffers(page) || PageChecked(page)) {
+	if (PageChecked(page)) {
 		/*
 		 * It's mmapped pagecache.  Add buffers and journal it.  There
 		 * doesn't seem much point in redirtying the page here.
 		 */
 		ClearPageChecked(page);
-		ret = block_prepare_write(page, 0, PAGE_CACHE_SIZE,
-					ext4_get_block);
-		if (ret != 0) {
-			ext4_journal_stop(handle);
-			goto out_unlock;
-		}
-		ret = walk_page_buffers(handle, page_buffers(page), 0,
-			PAGE_CACHE_SIZE, NULL, do_journal_get_write_access);
-
-		err = walk_page_buffers(handle, page_buffers(page), 0,
-				PAGE_CACHE_SIZE, NULL, write_end_fn);
-		if (ret == 0)
-			ret = err;
-		EXT4_I(inode)->i_state |= EXT4_STATE_JDATA;
-		unlock_page(page);
+		return __ext4_journalled_writepage(page, wbc);
 	} else {
 		/*
 		 * It may be a page full of checkpoint-mode buffers.  We don't
 		 * really know unless we go poke around in the buffer_heads.
 		 * But block_write_full_page will do the right thing.
 		 */
-		ret = block_write_full_page(page, ext4_get_block, wbc);
+		return block_write_full_page(page,
+						ext4_normal_get_block_write,
+						wbc);
 	}
-	err = ext4_journal_stop(handle);
-	if (!ret)
-		ret = err;
-out:
-	return ret;
-
 no_write:
 	redirty_page_for_writepage(wbc, page);
-out_unlock:
 	unlock_page(page);
-	goto out;
+	return 0;
 }
 
 static int ext4_readpage(struct file *file, struct page *page)
@@ -1819,7 +2808,7 @@ static int ext4_journalled_set_page_dirty(struct page *page)
 static const struct address_space_operations ext4_ordered_aops = {
 	.readpage	= ext4_readpage,
 	.readpages	= ext4_readpages,
-	.writepage	= ext4_ordered_writepage,
+	.writepage	= ext4_normal_writepage,
 	.sync_page	= block_sync_page,
 	.write_begin	= ext4_write_begin,
 	.write_end	= ext4_ordered_write_end,
@@ -1833,7 +2822,7 @@ static const struct address_space_operations ext4_ordered_aops = {
 static const struct address_space_operations ext4_writeback_aops = {
 	.readpage	= ext4_readpage,
 	.readpages	= ext4_readpages,
-	.writepage	= ext4_writeback_writepage,
+	.writepage	= ext4_normal_writepage,
 	.sync_page	= block_sync_page,
 	.write_begin	= ext4_write_begin,
 	.write_end	= ext4_writeback_write_end,
@@ -1857,10 +2846,31 @@ static const struct address_space_operations ext4_journalled_aops = {
 	.releasepage	= ext4_releasepage,
 };
 
+static const struct address_space_operations ext4_da_aops = {
+	.readpage	= ext4_readpage,
+	.readpages	= ext4_readpages,
+	.writepage	= ext4_da_writepage,
+	.writepages	= ext4_da_writepages,
+	.sync_page	= block_sync_page,
+	.write_begin	= ext4_da_write_begin,
+	.write_end	= ext4_da_write_end,
+	.bmap		= ext4_bmap,
+	.invalidatepage	= ext4_da_invalidatepage,
+	.releasepage	= ext4_releasepage,
+	.direct_IO	= ext4_direct_IO,
+	.migratepage	= buffer_migrate_page,
+};
+
 void ext4_set_aops(struct inode *inode)
 {
-	if (ext4_should_order_data(inode))
+	if (ext4_should_order_data(inode) &&
+		test_opt(inode->i_sb, DELALLOC))
+		inode->i_mapping->a_ops = &ext4_da_aops;
+	else if (ext4_should_order_data(inode))
 		inode->i_mapping->a_ops = &ext4_ordered_aops;
+	else if (ext4_should_writeback_data(inode) &&
+		 test_opt(inode->i_sb, DELALLOC))
+		inode->i_mapping->a_ops = &ext4_da_aops;
 	else if (ext4_should_writeback_data(inode))
 		inode->i_mapping->a_ops = &ext4_writeback_aops;
 	else
@@ -1873,7 +2883,7 @@ void ext4_set_aops(struct inode *inode)
  * This required during truncate. We need to physically zero the tail end
  * of that block so it doesn't yield old data if the file is later grown.
  */
-int ext4_block_truncate_page(handle_t *handle, struct page *page,
+int ext4_block_truncate_page(handle_t *handle,
 		struct address_space *mapping, loff_t from)
 {
 	ext4_fsblk_t index = from >> PAGE_CACHE_SHIFT;
@@ -1882,8 +2892,13 @@ int ext4_block_truncate_page(handle_t *handle, struct page *page,
 	ext4_lblk_t iblock;
 	struct inode *inode = mapping->host;
 	struct buffer_head *bh;
+	struct page *page;
 	int err = 0;
 
+	page = grab_cache_page(mapping, from >> PAGE_CACHE_SHIFT);
+	if (!page)
+		return -EINVAL;
+
 	blocksize = inode->i_sb->s_blocksize;
 	length = blocksize - (offset & (blocksize - 1));
 	iblock = index << (PAGE_CACHE_SHIFT - inode->i_sb->s_blocksize_bits);
@@ -1956,7 +2971,7 @@ int ext4_block_truncate_page(handle_t *handle, struct page *page,
 		err = ext4_journal_dirty_metadata(handle, bh);
 	} else {
 		if (ext4_should_order_data(inode))
-			err = ext4_journal_dirty_data(handle, bh);
+			err = ext4_jbd2_file_inode(handle, inode);
 		mark_buffer_dirty(bh);
 	}
 
@@ -2179,7 +3194,21 @@ static void ext4_free_data(handle_t *handle, struct inode *inode,
 
 	if (this_bh) {
 		BUFFER_TRACE(this_bh, "call ext4_journal_dirty_metadata");
-		ext4_journal_dirty_metadata(handle, this_bh);
+
+		/*
+		 * The buffer head should have an attached journal head at this
+		 * point. However, if the data is corrupted and an indirect
+		 * block pointed to itself, it would have been detached when
+		 * the block was cleared. Check for this instead of OOPSing.
+		 */
+		if (bh2jh(this_bh))
+			ext4_journal_dirty_metadata(handle, this_bh);
+		else
+			ext4_error(inode->i_sb, __func__,
+				   "circular indirect block detected, "
+				   "inode=%lu, block=%llu",
+				   inode->i_ino,
+				   (unsigned long long) this_bh->b_blocknr);
 	}
 }
 
@@ -2305,6 +3334,19 @@ static void ext4_free_branches(handle_t *handle, struct inode *inode,
 	}
 }
 
+int ext4_can_truncate(struct inode *inode)
+{
+	if (IS_APPEND(inode) || IS_IMMUTABLE(inode))
+		return 0;
+	if (S_ISREG(inode->i_mode))
+		return 1;
+	if (S_ISDIR(inode->i_mode))
+		return 1;
+	if (S_ISLNK(inode->i_mode))
+		return !ext4_inode_is_fast_symlink(inode);
+	return 0;
+}
+
 /*
  * ext4_truncate()
  *
@@ -2347,51 +3389,25 @@ void ext4_truncate(struct inode *inode)
 	int n;
 	ext4_lblk_t last_block;
 	unsigned blocksize = inode->i_sb->s_blocksize;
-	struct page *page;
 
-	if (!(S_ISREG(inode->i_mode) || S_ISDIR(inode->i_mode) ||
-	    S_ISLNK(inode->i_mode)))
-		return;
-	if (ext4_inode_is_fast_symlink(inode))
-		return;
-	if (IS_APPEND(inode) || IS_IMMUTABLE(inode))
+	if (!ext4_can_truncate(inode))
 		return;
 
-	/*
-	 * We have to lock the EOF page here, because lock_page() nests
-	 * outside jbd2_journal_start().
-	 */
-	if ((inode->i_size & (blocksize - 1)) == 0) {
-		/* Block boundary? Nothing to do */
-		page = NULL;
-	} else {
-		page = grab_cache_page(mapping,
-				inode->i_size >> PAGE_CACHE_SHIFT);
-		if (!page)
-			return;
-	}
-
 	if (EXT4_I(inode)->i_flags & EXT4_EXTENTS_FL) {
-		ext4_ext_truncate(inode, page);
+		ext4_ext_truncate(inode);
 		return;
 	}
 
 	handle = start_transaction(inode);
-	if (IS_ERR(handle)) {
-		if (page) {
-			clear_highpage(page);
-			flush_dcache_page(page);
-			unlock_page(page);
-			page_cache_release(page);
-		}
+	if (IS_ERR(handle))
 		return;		/* AKPM: return what? */
-	}
 
 	last_block = (inode->i_size + blocksize-1)
 					>> EXT4_BLOCK_SIZE_BITS(inode->i_sb);
 
-	if (page)
-		ext4_block_truncate_page(handle, page, mapping, inode->i_size);
+	if (inode->i_size & (blocksize - 1))
+		if (ext4_block_truncate_page(handle, mapping, inode->i_size))
+			goto out_stop;
 
 	n = ext4_block_to_path(inode, last_block, offsets, NULL);
 	if (n == 0)
@@ -2410,6 +3426,11 @@ void ext4_truncate(struct inode *inode)
 		goto out_stop;
 
 	/*
+	 * From here we block out all ext4_get_block() callers who want to
+	 * modify the block allocation tree.
+	 */
+	down_write(&ei->i_data_sem);
+	/*
 	 * The orphan list entry will now protect us from any crash which
 	 * occurs before the truncate completes, so it is now safe to propagate
 	 * the new, shorter inode size (held for now in i_size) into the
@@ -2418,12 +3439,6 @@ void ext4_truncate(struct inode *inode)
 	 */
 	ei->i_disksize = inode->i_size;
 
-	/*
-	 * From here we block out all ext4_get_block() callers who want to
-	 * modify the block allocation tree.
-	 */
-	down_write(&ei->i_data_sem);
-
 	if (n == 1) {		/* direct blocks */
 		ext4_free_data(handle, inode, NULL, i_data+offsets[0],
 			       i_data + EXT4_NDIR_BLOCKS);
@@ -3107,7 +4122,14 @@ int ext4_write_inode(struct inode *inode, int wait)
  * be freed, so we have a strong guarantee that no future commit will
  * leave these blocks visible to the user.)
  *
- * Called with inode->sem down.
+ * Another thing we have to assure is that if we are in ordered mode
+ * and inode is still attached to the committing transaction, we must
+ * we start writeout of all the dirty pages which are being truncated.
+ * This way we are sure that all the data written in the previous
+ * transaction are already on disk (truncate waits for pages under
+ * writeback).
+ *
+ * Called with inode->i_mutex down.
  */
 int ext4_setattr(struct dentry *dentry, struct iattr *attr)
 {
@@ -3173,6 +4195,22 @@ int ext4_setattr(struct dentry *dentry, struct iattr *attr)
 		if (!error)
 			error = rc;
 		ext4_journal_stop(handle);
+
+		if (ext4_should_order_data(inode)) {
+			error = ext4_begin_ordered_truncate(inode,
+							    attr->ia_size);
+			if (error) {
+				/* Do as much error cleanup as possible */
+				handle = ext4_journal_start(inode, 3);
+				if (IS_ERR(handle)) {
+					ext4_orphan_del(NULL, inode);
+					goto err_out;
+				}
+				ext4_orphan_del(handle, inode);
+				ext4_journal_stop(handle);
+				goto err_out;
+			}
+		}
 	}
 
 	rc = inode_setattr(inode, attr);
@@ -3193,6 +4231,32 @@ err_out:
 	return error;
 }
 
+int ext4_getattr(struct vfsmount *mnt, struct dentry *dentry,
+		 struct kstat *stat)
+{
+	struct inode *inode;
+	unsigned long delalloc_blocks;
+
+	inode = dentry->d_inode;
+	generic_fillattr(inode, stat);
+
+	/*
+	 * We can't update i_blocks if the block allocation is delayed
+	 * otherwise in the case of system crash before the real block
+	 * allocation is done, we will have i_blocks inconsistent with
+	 * on-disk file blocks.
+	 * We always keep i_blocks updated together with real
+	 * allocation. But to not confuse with user, stat
+	 * will return the blocks that include the delayed allocation
+	 * blocks for this file.
+	 */
+	spin_lock(&EXT4_I(inode)->i_block_reservation_lock);
+	delalloc_blocks = EXT4_I(inode)->i_reserved_data_blocks;
+	spin_unlock(&EXT4_I(inode)->i_block_reservation_lock);
+
+	stat->blocks += (delalloc_blocks << inode->i_sb->s_blocksize_bits)>>9;
+	return 0;
+}
 
 /*
  * How many blocks doth make a writepage()?
@@ -3506,3 +4570,64 @@ int ext4_change_inode_journal_flag(struct inode *inode, int val)
 
 	return err;
 }
+
+static int ext4_bh_unmapped(handle_t *handle, struct buffer_head *bh)
+{
+	return !buffer_mapped(bh);
+}
+
+int ext4_page_mkwrite(struct vm_area_struct *vma, struct page *page)
+{
+	loff_t size;
+	unsigned long len;
+	int ret = -EINVAL;
+	struct file *file = vma->vm_file;
+	struct inode *inode = file->f_path.dentry->d_inode;
+	struct address_space *mapping = inode->i_mapping;
+
+	/*
+	 * Get i_alloc_sem to stop truncates messing with the inode. We cannot
+	 * get i_mutex because we are already holding mmap_sem.
+	 */
+	down_read(&inode->i_alloc_sem);
+	size = i_size_read(inode);
+	if (page->mapping != mapping || size <= page_offset(page)
+	    || !PageUptodate(page)) {
+		/* page got truncated from under us? */
+		goto out_unlock;
+	}
+	ret = 0;
+	if (PageMappedToDisk(page))
+		goto out_unlock;
+
+	if (page->index == size >> PAGE_CACHE_SHIFT)
+		len = size & ~PAGE_CACHE_MASK;
+	else
+		len = PAGE_CACHE_SIZE;
+
+	if (page_has_buffers(page)) {
+		/* return if we have all the buffers mapped */
+		if (!walk_page_buffers(NULL, page_buffers(page), 0, len, NULL,
+				       ext4_bh_unmapped))
+			goto out_unlock;
+	}
+	/*
+	 * OK, we need to fill the hole... Do write_begin write_end
+	 * to do block allocation/reservation.We are not holding
+	 * inode.i__mutex here. That allow * parallel write_begin,
+	 * write_end call. lock_page prevent this from happening
+	 * on the same page though
+	 */
+	ret = mapping->a_ops->write_begin(file, mapping, page_offset(page),
+			len, AOP_FLAG_UNINTERRUPTIBLE, &page, NULL);
+	if (ret < 0)
+		goto out_unlock;
+	ret = mapping->a_ops->write_end(file, mapping, page_offset(page),
+			len, len, page, NULL);
+	if (ret < 0)
+		goto out_unlock;
+	ret = 0;
+out_unlock:
+	up_read(&inode->i_alloc_sem);
+	return ret;
+}
diff --git a/fs/ext4/mballoc.c b/fs/ext4/mballoc.c
index c9900aade15..8d141a25bbe 100644
--- a/fs/ext4/mballoc.c
+++ b/fs/ext4/mballoc.c
@@ -381,22 +381,28 @@ static inline void mb_clear_bit_atomic(spinlock_t *lock, int bit, void *addr)
 
 static inline int mb_find_next_zero_bit(void *addr, int max, int start)
 {
-	int fix = 0;
+	int fix = 0, ret, tmpmax;
 	addr = mb_correct_addr_and_bit(&fix, addr);
-	max += fix;
+	tmpmax = max + fix;
 	start += fix;
 
-	return ext4_find_next_zero_bit(addr, max, start) - fix;
+	ret = ext4_find_next_zero_bit(addr, tmpmax, start) - fix;
+	if (ret > max)
+		return max;
+	return ret;
 }
 
 static inline int mb_find_next_bit(void *addr, int max, int start)
 {
-	int fix = 0;
+	int fix = 0, ret, tmpmax;
 	addr = mb_correct_addr_and_bit(&fix, addr);
-	max += fix;
+	tmpmax = max + fix;
 	start += fix;
 
-	return ext4_find_next_bit(addr, max, start) - fix;
+	ret = ext4_find_next_bit(addr, tmpmax, start) - fix;
+	if (ret > max)
+		return max;
+	return ret;
 }
 
 static void *mb_find_buddy(struct ext4_buddy *e4b, int order, int *max)
@@ -803,6 +809,7 @@ static int ext4_mb_init_cache(struct page *page, char *incore)
 		if (!buffer_uptodate(bh[i]))
 			goto out;
 
+	err = 0;
 	first_block = page->index * blocks_per_page;
 	for (i = 0; i < blocks_per_page; i++) {
 		int group;
@@ -883,6 +890,7 @@ ext4_mb_load_buddy(struct super_block *sb, ext4_group_t group,
 	int pnum;
 	int poff;
 	struct page *page;
+	int ret;
 
 	mb_debug("load group %lu\n", group);
 
@@ -914,15 +922,21 @@ ext4_mb_load_buddy(struct super_block *sb, ext4_group_t group,
 		if (page) {
 			BUG_ON(page->mapping != inode->i_mapping);
 			if (!PageUptodate(page)) {
-				ext4_mb_init_cache(page, NULL);
+				ret = ext4_mb_init_cache(page, NULL);
+				if (ret) {
+					unlock_page(page);
+					goto err;
+				}
 				mb_cmp_bitmaps(e4b, page_address(page) +
 					       (poff * sb->s_blocksize));
 			}
 			unlock_page(page);
 		}
 	}
-	if (page == NULL || !PageUptodate(page))
+	if (page == NULL || !PageUptodate(page)) {
+		ret = -EIO;
 		goto err;
+	}
 	e4b->bd_bitmap_page = page;
 	e4b->bd_bitmap = page_address(page) + (poff * sb->s_blocksize);
 	mark_page_accessed(page);
@@ -938,14 +952,20 @@ ext4_mb_load_buddy(struct super_block *sb, ext4_group_t group,
 		page = find_or_create_page(inode->i_mapping, pnum, GFP_NOFS);
 		if (page) {
 			BUG_ON(page->mapping != inode->i_mapping);
-			if (!PageUptodate(page))
-				ext4_mb_init_cache(page, e4b->bd_bitmap);
-
+			if (!PageUptodate(page)) {
+				ret = ext4_mb_init_cache(page, e4b->bd_bitmap);
+				if (ret) {
+					unlock_page(page);
+					goto err;
+				}
+			}
 			unlock_page(page);
 		}
 	}
-	if (page == NULL || !PageUptodate(page))
+	if (page == NULL || !PageUptodate(page)) {
+		ret = -EIO;
 		goto err;
+	}
 	e4b->bd_buddy_page = page;
 	e4b->bd_buddy = page_address(page) + (poff * sb->s_blocksize);
 	mark_page_accessed(page);
@@ -962,7 +982,7 @@ err:
 		page_cache_release(e4b->bd_buddy_page);
 	e4b->bd_buddy = NULL;
 	e4b->bd_bitmap = NULL;
-	return -EIO;
+	return ret;
 }
 
 static void ext4_mb_release_desc(struct ext4_buddy *e4b)
@@ -1031,7 +1051,7 @@ static void mb_set_bits(spinlock_t *lock, void *bm, int cur, int len)
 	}
 }
 
-static int mb_free_blocks(struct inode *inode, struct ext4_buddy *e4b,
+static void mb_free_blocks(struct inode *inode, struct ext4_buddy *e4b,
 			  int first, int count)
 {
 	int block = 0;
@@ -1071,11 +1091,12 @@ static int mb_free_blocks(struct inode *inode, struct ext4_buddy *e4b,
 			blocknr += block;
 			blocknr +=
 			    le32_to_cpu(EXT4_SB(sb)->s_es->s_first_data_block);
-
+			ext4_unlock_group(sb, e4b->bd_group);
 			ext4_error(sb, __func__, "double-free of inode"
 				   " %lu's block %llu(bit %u in group %lu)\n",
 				   inode ? inode->i_ino : 0, blocknr, block,
 				   e4b->bd_group);
+			ext4_lock_group(sb, e4b->bd_group);
 		}
 		mb_clear_bit(block, EXT4_MB_BITMAP(e4b));
 		e4b->bd_info->bb_counters[order]++;
@@ -1113,8 +1134,6 @@ static int mb_free_blocks(struct inode *inode, struct ext4_buddy *e4b,
 		} while (1);
 	}
 	mb_check_buddy(e4b);
-
-	return 0;
 }
 
 static int mb_find_extent(struct ext4_buddy *e4b, int order, int block,
@@ -1730,10 +1749,6 @@ ext4_mb_regular_allocator(struct ext4_allocation_context *ac)
 		ac->ac_g_ex.fe_start = sbi->s_mb_last_start;
 		spin_unlock(&sbi->s_md_lock);
 	}
-
-	/* searching for the right group start from the goal value specified */
-	group = ac->ac_g_ex.fe_group;
-
 	/* Let's just scan groups to find more-less suitable blocks */
 	cr = ac->ac_2order ? 0 : 1;
 	/*
@@ -1743,6 +1758,12 @@ ext4_mb_regular_allocator(struct ext4_allocation_context *ac)
 repeat:
 	for (; cr < 4 && ac->ac_status == AC_STATUS_CONTINUE; cr++) {
 		ac->ac_criteria = cr;
+		/*
+		 * searching for the right group start
+		 * from the goal value specified
+		 */
+		group = ac->ac_g_ex.fe_group;
+
 		for (i = 0; i < EXT4_SB(sb)->s_groups_count; group++, i++) {
 			struct ext4_group_info *grp;
 			struct ext4_group_desc *desc;
@@ -1963,6 +1984,8 @@ static int ext4_mb_seq_history_open(struct inode *inode, struct file *file)
 	int rc;
 	int size;
 
+	if (unlikely(sbi->s_mb_history == NULL))
+		return -ENOMEM;
 	s = kmalloc(sizeof(*s), GFP_KERNEL);
 	if (s == NULL)
 		return -ENOMEM;
@@ -2165,9 +2188,7 @@ static void ext4_mb_history_init(struct super_block *sb)
 	sbi->s_mb_history_cur = 0;
 	spin_lock_init(&sbi->s_mb_history_lock);
 	i = sbi->s_mb_history_max * sizeof(struct ext4_mb_history);
-	sbi->s_mb_history = kmalloc(i, GFP_KERNEL);
-	if (likely(sbi->s_mb_history != NULL))
-		memset(sbi->s_mb_history, 0, i);
+	sbi->s_mb_history = kzalloc(i, GFP_KERNEL);
 	/* if we can't allocate history, then we simple won't use it */
 }
 
@@ -2215,21 +2236,192 @@ ext4_mb_store_history(struct ext4_allocation_context *ac)
 #define ext4_mb_history_init(sb)
 #endif
 
+
+/* Create and initialize ext4_group_info data for the given group. */
+int ext4_mb_add_groupinfo(struct super_block *sb, ext4_group_t group,
+			  struct ext4_group_desc *desc)
+{
+	int i, len;
+	int metalen = 0;
+	struct ext4_sb_info *sbi = EXT4_SB(sb);
+	struct ext4_group_info **meta_group_info;
+
+	/*
+	 * First check if this group is the first of a reserved block.
+	 * If it's true, we have to allocate a new table of pointers
+	 * to ext4_group_info structures
+	 */
+	if (group % EXT4_DESC_PER_BLOCK(sb) == 0) {
+		metalen = sizeof(*meta_group_info) <<
+			EXT4_DESC_PER_BLOCK_BITS(sb);
+		meta_group_info = kmalloc(metalen, GFP_KERNEL);
+		if (meta_group_info == NULL) {
+			printk(KERN_ERR "EXT4-fs: can't allocate mem for a "
+			       "buddy group\n");
+			goto exit_meta_group_info;
+		}
+		sbi->s_group_info[group >> EXT4_DESC_PER_BLOCK_BITS(sb)] =
+			meta_group_info;
+	}
+
+	/*
+	 * calculate needed size. if change bb_counters size,
+	 * don't forget about ext4_mb_generate_buddy()
+	 */
+	len = offsetof(typeof(**meta_group_info),
+		       bb_counters[sb->s_blocksize_bits + 2]);
+
+	meta_group_info =
+		sbi->s_group_info[group >> EXT4_DESC_PER_BLOCK_BITS(sb)];
+	i = group & (EXT4_DESC_PER_BLOCK(sb) - 1);
+
+	meta_group_info[i] = kzalloc(len, GFP_KERNEL);
+	if (meta_group_info[i] == NULL) {
+		printk(KERN_ERR "EXT4-fs: can't allocate buddy mem\n");
+		goto exit_group_info;
+	}
+	set_bit(EXT4_GROUP_INFO_NEED_INIT_BIT,
+		&(meta_group_info[i]->bb_state));
+
+	/*
+	 * initialize bb_free to be able to skip
+	 * empty groups without initialization
+	 */
+	if (desc->bg_flags & cpu_to_le16(EXT4_BG_BLOCK_UNINIT)) {
+		meta_group_info[i]->bb_free =
+			ext4_free_blocks_after_init(sb, group, desc);
+	} else {
+		meta_group_info[i]->bb_free =
+			le16_to_cpu(desc->bg_free_blocks_count);
+	}
+
+	INIT_LIST_HEAD(&meta_group_info[i]->bb_prealloc_list);
+
+#ifdef DOUBLE_CHECK
+	{
+		struct buffer_head *bh;
+		meta_group_info[i]->bb_bitmap =
+			kmalloc(sb->s_blocksize, GFP_KERNEL);
+		BUG_ON(meta_group_info[i]->bb_bitmap == NULL);
+		bh = ext4_read_block_bitmap(sb, group);
+		BUG_ON(bh == NULL);
+		memcpy(meta_group_info[i]->bb_bitmap, bh->b_data,
+			sb->s_blocksize);
+		put_bh(bh);
+	}
+#endif
+
+	return 0;
+
+exit_group_info:
+	/* If a meta_group_info table has been allocated, release it now */
+	if (group % EXT4_DESC_PER_BLOCK(sb) == 0)
+		kfree(sbi->s_group_info[group >> EXT4_DESC_PER_BLOCK_BITS(sb)]);
+exit_meta_group_info:
+	return -ENOMEM;
+} /* ext4_mb_add_groupinfo */
+
+/*
+ * Add a group to the existing groups.
+ * This function is used for online resize
+ */
+int ext4_mb_add_more_groupinfo(struct super_block *sb, ext4_group_t group,
+			       struct ext4_group_desc *desc)
+{
+	struct ext4_sb_info *sbi = EXT4_SB(sb);
+	struct inode *inode = sbi->s_buddy_cache;
+	int blocks_per_page;
+	int block;
+	int pnum;
+	struct page *page;
+	int err;
+
+	/* Add group based on group descriptor*/
+	err = ext4_mb_add_groupinfo(sb, group, desc);
+	if (err)
+		return err;
+
+	/*
+	 * Cache pages containing dynamic mb_alloc datas (buddy and bitmap
+	 * datas) are set not up to date so that they will be re-initilaized
+	 * during the next call to ext4_mb_load_buddy
+	 */
+
+	/* Set buddy page as not up to date */
+	blocks_per_page = PAGE_CACHE_SIZE / sb->s_blocksize;
+	block = group * 2;
+	pnum = block / blocks_per_page;
+	page = find_get_page(inode->i_mapping, pnum);
+	if (page != NULL) {
+		ClearPageUptodate(page);
+		page_cache_release(page);
+	}
+
+	/* Set bitmap page as not up to date */
+	block++;
+	pnum = block / blocks_per_page;
+	page = find_get_page(inode->i_mapping, pnum);
+	if (page != NULL) {
+		ClearPageUptodate(page);
+		page_cache_release(page);
+	}
+
+	return 0;
+}
+
+/*
+ * Update an existing group.
+ * This function is used for online resize
+ */
+void ext4_mb_update_group_info(struct ext4_group_info *grp, ext4_grpblk_t add)
+{
+	grp->bb_free += add;
+}
+
 static int ext4_mb_init_backend(struct super_block *sb)
 {
 	ext4_group_t i;
-	int j, len, metalen;
+	int metalen;
 	struct ext4_sb_info *sbi = EXT4_SB(sb);
-	int num_meta_group_infos =
-		(sbi->s_groups_count + EXT4_DESC_PER_BLOCK(sb) - 1) >>
-			EXT4_DESC_PER_BLOCK_BITS(sb);
+	struct ext4_super_block *es = sbi->s_es;
+	int num_meta_group_infos;
+	int num_meta_group_infos_max;
+	int array_size;
 	struct ext4_group_info **meta_group_info;
+	struct ext4_group_desc *desc;
+
+	/* This is the number of blocks used by GDT */
+	num_meta_group_infos = (sbi->s_groups_count + EXT4_DESC_PER_BLOCK(sb) -
+				1) >> EXT4_DESC_PER_BLOCK_BITS(sb);
+
+	/*
+	 * This is the total number of blocks used by GDT including
+	 * the number of reserved blocks for GDT.
+	 * The s_group_info array is allocated with this value
+	 * to allow a clean online resize without a complex
+	 * manipulation of pointer.
+	 * The drawback is the unused memory when no resize
+	 * occurs but it's very low in terms of pages
+	 * (see comments below)
+	 * Need to handle this properly when META_BG resizing is allowed
+	 */
+	num_meta_group_infos_max = num_meta_group_infos +
+				le16_to_cpu(es->s_reserved_gdt_blocks);
 
+	/*
+	 * array_size is the size of s_group_info array. We round it
+	 * to the next power of two because this approximation is done
+	 * internally by kmalloc so we can have some more memory
+	 * for free here (e.g. may be used for META_BG resize).
+	 */
+	array_size = 1;
+	while (array_size < sizeof(*sbi->s_group_info) *
+	       num_meta_group_infos_max)
+		array_size = array_size << 1;
 	/* An 8TB filesystem with 64-bit pointers requires a 4096 byte
 	 * kmalloc. A 128kb malloc should suffice for a 256TB filesystem.
 	 * So a two level scheme suffices for now. */
-	sbi->s_group_info = kmalloc(sizeof(*sbi->s_group_info) *
-				    num_meta_group_infos, GFP_KERNEL);
+	sbi->s_group_info = kmalloc(array_size, GFP_KERNEL);
 	if (sbi->s_group_info == NULL) {
 		printk(KERN_ERR "EXT4-fs: can't allocate buddy meta group\n");
 		return -ENOMEM;
@@ -2256,63 +2448,15 @@ static int ext4_mb_init_backend(struct super_block *sb)
 		sbi->s_group_info[i] = meta_group_info;
 	}
 
-	/*
-	 * calculate needed size. if change bb_counters size,
-	 * don't forget about ext4_mb_generate_buddy()
-	 */
-	len = sizeof(struct ext4_group_info);
-	len += sizeof(unsigned short) * (sb->s_blocksize_bits + 2);
 	for (i = 0; i < sbi->s_groups_count; i++) {
-		struct ext4_group_desc *desc;
-
-		meta_group_info =
-			sbi->s_group_info[i >> EXT4_DESC_PER_BLOCK_BITS(sb)];
-		j = i & (EXT4_DESC_PER_BLOCK(sb) - 1);
-
-		meta_group_info[j] = kzalloc(len, GFP_KERNEL);
-		if (meta_group_info[j] == NULL) {
-			printk(KERN_ERR "EXT4-fs: can't allocate buddy mem\n");
-			goto err_freebuddy;
-		}
 		desc = ext4_get_group_desc(sb, i, NULL);
 		if (desc == NULL) {
 			printk(KERN_ERR
 				"EXT4-fs: can't read descriptor %lu\n", i);
-			i++;
 			goto err_freebuddy;
 		}
-		memset(meta_group_info[j], 0, len);
-		set_bit(EXT4_GROUP_INFO_NEED_INIT_BIT,
-			&(meta_group_info[j]->bb_state));
-
-		/*
-		 * initialize bb_free to be able to skip
-		 * empty groups without initialization
-		 */
-		if (desc->bg_flags & cpu_to_le16(EXT4_BG_BLOCK_UNINIT)) {
-			meta_group_info[j]->bb_free =
-				ext4_free_blocks_after_init(sb, i, desc);
-		} else {
-			meta_group_info[j]->bb_free =
-				le16_to_cpu(desc->bg_free_blocks_count);
-		}
-
-		INIT_LIST_HEAD(&meta_group_info[j]->bb_prealloc_list);
-
-#ifdef DOUBLE_CHECK
-		{
-			struct buffer_head *bh;
-			meta_group_info[j]->bb_bitmap =
-				kmalloc(sb->s_blocksize, GFP_KERNEL);
-			BUG_ON(meta_group_info[j]->bb_bitmap == NULL);
-			bh = read_block_bitmap(sb, i);
-			BUG_ON(bh == NULL);
-			memcpy(meta_group_info[j]->bb_bitmap, bh->b_data,
-					sb->s_blocksize);
-			put_bh(bh);
-		}
-#endif
-
+		if (ext4_mb_add_groupinfo(sb, i, desc) != 0)
+			goto err_freebuddy;
 	}
 
 	return 0;
@@ -2336,6 +2480,7 @@ int ext4_mb_init(struct super_block *sb, int needs_recovery)
 	unsigned i;
 	unsigned offset;
 	unsigned max;
+	int ret;
 
 	if (!test_opt(sb, MBALLOC))
 		return 0;
@@ -2370,12 +2515,12 @@ int ext4_mb_init(struct super_block *sb, int needs_recovery)
 	} while (i <= sb->s_blocksize_bits + 1);
 
 	/* init file for buddy data */
-	i = ext4_mb_init_backend(sb);
-	if (i) {
+	ret = ext4_mb_init_backend(sb);
+	if (ret != 0) {
 		clear_opt(sbi->s_mount_opt, MBALLOC);
 		kfree(sbi->s_mb_offsets);
 		kfree(sbi->s_mb_maxs);
-		return i;
+		return ret;
 	}
 
 	spin_lock_init(&sbi->s_md_lock);
@@ -2548,8 +2693,7 @@ ext4_mb_free_committed_blocks(struct super_block *sb)
 		ext4_lock_group(sb, md->group);
 		for (i = 0; i < md->num; i++) {
 			mb_debug(" %u", md->blocks[i]);
-			err = mb_free_blocks(NULL, &e4b, md->blocks[i], 1);
-			BUG_ON(err != 0);
+			mb_free_blocks(NULL, &e4b, md->blocks[i], 1);
 		}
 		mb_debug("\n");
 		ext4_unlock_group(sb, md->group);
@@ -2575,25 +2719,24 @@ ext4_mb_free_committed_blocks(struct super_block *sb)
 
 
 
-#define MB_PROC_VALUE_READ(name)				\
-static int ext4_mb_read_##name(char *page, char **start,	\
-		off_t off, int count, int *eof, void *data)	\
+#define MB_PROC_FOPS(name)					\
+static int ext4_mb_##name##_proc_show(struct seq_file *m, void *v)	\
 {								\
-	struct ext4_sb_info *sbi = data;			\
-	int len;						\
-	*eof = 1;						\
-	if (off != 0)						\
-		return 0;					\
-	len = sprintf(page, "%ld\n", sbi->s_mb_##name);		\
-	*start = page;						\
-	return len;						\
-}
-
-#define MB_PROC_VALUE_WRITE(name)				\
-static int ext4_mb_write_##name(struct file *file,		\
-		const char __user *buf, unsigned long cnt, void *data)	\
+	struct ext4_sb_info *sbi = m->private;			\
+								\
+	seq_printf(m, "%ld\n", sbi->s_mb_##name);		\
+	return 0;						\
+}								\
+								\
+static int ext4_mb_##name##_proc_open(struct inode *inode, struct file *file)\
+{								\
+	return single_open(file, ext4_mb_##name##_proc_show, PDE(inode)->data);\
+}								\
+								\
+static ssize_t ext4_mb_##name##_proc_write(struct file *file,	\
+		const char __user *buf, size_t cnt, loff_t *ppos)	\
 {								\
-	struct ext4_sb_info *sbi = data;			\
+	struct ext4_sb_info *sbi = PDE(file->f_path.dentry->d_inode)->data;\
 	char str[32];						\
 	long value;						\
 	if (cnt >= sizeof(str))					\
@@ -2605,31 +2748,32 @@ static int ext4_mb_write_##name(struct file *file,		\
 		return -ERANGE;					\
 	sbi->s_mb_##name = value;				\
 	return cnt;						\
-}
+}								\
+								\
+static const struct file_operations ext4_mb_##name##_proc_fops = {	\
+	.owner		= THIS_MODULE,				\
+	.open		= ext4_mb_##name##_proc_open,		\
+	.read		= seq_read,				\
+	.llseek		= seq_lseek,				\
+	.release	= single_release,			\
+	.write		= ext4_mb_##name##_proc_write,		\
+};
 
-MB_PROC_VALUE_READ(stats);
-MB_PROC_VALUE_WRITE(stats);
-MB_PROC_VALUE_READ(max_to_scan);
-MB_PROC_VALUE_WRITE(max_to_scan);
-MB_PROC_VALUE_READ(min_to_scan);
-MB_PROC_VALUE_WRITE(min_to_scan);
-MB_PROC_VALUE_READ(order2_reqs);
-MB_PROC_VALUE_WRITE(order2_reqs);
-MB_PROC_VALUE_READ(stream_request);
-MB_PROC_VALUE_WRITE(stream_request);
-MB_PROC_VALUE_READ(group_prealloc);
-MB_PROC_VALUE_WRITE(group_prealloc);
+MB_PROC_FOPS(stats);
+MB_PROC_FOPS(max_to_scan);
+MB_PROC_FOPS(min_to_scan);
+MB_PROC_FOPS(order2_reqs);
+MB_PROC_FOPS(stream_request);
+MB_PROC_FOPS(group_prealloc);
 
 #define	MB_PROC_HANDLER(name, var)					\
 do {									\
-	proc = create_proc_entry(name, mode, sbi->s_mb_proc);		\
+	proc = proc_create_data(name, mode, sbi->s_mb_proc,		\
+				&ext4_mb_##var##_proc_fops, sbi);	\
 	if (proc == NULL) {						\
 		printk(KERN_ERR "EXT4-fs: can't to create %s\n", name);	\
 		goto err_out;						\
 	}								\
-	proc->data = sbi;						\
-	proc->read_proc  = ext4_mb_read_##var ;				\
-	proc->write_proc = ext4_mb_write_##var;				\
 } while (0)
 
 static int ext4_mb_init_per_dev_proc(struct super_block *sb)
@@ -2639,6 +2783,10 @@ static int ext4_mb_init_per_dev_proc(struct super_block *sb)
 	struct proc_dir_entry *proc;
 	char devname[64];
 
+	if (proc_root_ext4 == NULL) {
+		sbi->s_mb_proc = NULL;
+		return -EINVAL;
+	}
 	bdevname(sb->s_bdev, devname);
 	sbi->s_mb_proc = proc_mkdir(devname, proc_root_ext4);
 
@@ -2747,7 +2895,7 @@ ext4_mb_mark_diskspace_used(struct ext4_allocation_context *ac,
 
 
 	err = -EIO;
-	bitmap_bh = read_block_bitmap(sb, ac->ac_b_ex.fe_group);
+	bitmap_bh = ext4_read_block_bitmap(sb, ac->ac_b_ex.fe_group);
 	if (!bitmap_bh)
 		goto out_err;
 
@@ -2816,7 +2964,23 @@ ext4_mb_mark_diskspace_used(struct ext4_allocation_context *ac,
 	le16_add_cpu(&gdp->bg_free_blocks_count, -ac->ac_b_ex.fe_len);
 	gdp->bg_checksum = ext4_group_desc_csum(sbi, ac->ac_b_ex.fe_group, gdp);
 	spin_unlock(sb_bgl_lock(sbi, ac->ac_b_ex.fe_group));
-	percpu_counter_sub(&sbi->s_freeblocks_counter, ac->ac_b_ex.fe_len);
+
+	/*
+	 * free blocks account has already be reduced/reserved
+	 * at write_begin() time for delayed allocation
+	 * do not double accounting
+	 */
+	if (!(ac->ac_flags & EXT4_MB_DELALLOC_RESERVED))
+		percpu_counter_sub(&sbi->s_freeblocks_counter,
+					ac->ac_b_ex.fe_len);
+
+	if (sbi->s_log_groups_per_flex) {
+		ext4_group_t flex_group = ext4_flex_group(sbi,
+							  ac->ac_b_ex.fe_group);
+		spin_lock(sb_bgl_lock(sbi, flex_group));
+		sbi->s_flex_groups[flex_group].free_blocks -= ac->ac_b_ex.fe_len;
+		spin_unlock(sb_bgl_lock(sbi, flex_group));
+	}
 
 	err = ext4_journal_dirty_metadata(handle, bitmap_bh);
 	if (err)
@@ -3473,8 +3637,6 @@ ext4_mb_release_inode_pa(struct ext4_buddy *e4b, struct buffer_head *bitmap_bh,
 		if (bit >= end)
 			break;
 		next = mb_find_next_bit(bitmap_bh->b_data, end, bit);
-		if (next > end)
-			next = end;
 		start = group * EXT4_BLOCKS_PER_GROUP(sb) + bit +
 				le32_to_cpu(sbi->s_es->s_first_data_block);
 		mb_debug("    free preallocated %u/%u in group %u\n",
@@ -3569,7 +3731,7 @@ ext4_mb_discard_group_preallocations(struct super_block *sb,
 	if (list_empty(&grp->bb_prealloc_list))
 		return 0;
 
-	bitmap_bh = read_block_bitmap(sb, group);
+	bitmap_bh = ext4_read_block_bitmap(sb, group);
 	if (bitmap_bh == NULL) {
 		/* error handling here */
 		ext4_mb_release_desc(&e4b);
@@ -3743,7 +3905,7 @@ repeat:
 		err = ext4_mb_load_buddy(sb, group, &e4b);
 		BUG_ON(err != 0); /* error handling here */
 
-		bitmap_bh = read_block_bitmap(sb, group);
+		bitmap_bh = ext4_read_block_bitmap(sb, group);
 		if (bitmap_bh == NULL) {
 			/* error handling here */
 			ext4_mb_release_desc(&e4b);
@@ -4011,10 +4173,21 @@ ext4_fsblk_t ext4_mb_new_blocks(handle_t *handle,
 	sbi = EXT4_SB(sb);
 
 	if (!test_opt(sb, MBALLOC)) {
-		block = ext4_new_blocks_old(handle, ar->inode, ar->goal,
+		block = ext4_old_new_blocks(handle, ar->inode, ar->goal,
 					    &(ar->len), errp);
 		return block;
 	}
+	if (!EXT4_I(ar->inode)->i_delalloc_reserved_flag) {
+		/*
+		 * With delalloc we already reserved the blocks
+		 */
+		ar->len = ext4_has_free_blocks(sbi, ar->len);
+	}
+
+	if (ar->len == 0) {
+		*errp = -ENOSPC;
+		return 0;
+	}
 
 	while (ar->len && DQUOT_ALLOC_BLOCK(ar->inode, ar->len)) {
 		ar->flags |= EXT4_MB_HINT_NOPREALLOC;
@@ -4026,10 +4199,14 @@ ext4_fsblk_t ext4_mb_new_blocks(handle_t *handle,
 	}
 	inquota = ar->len;
 
+	if (EXT4_I(ar->inode)->i_delalloc_reserved_flag)
+		ar->flags |= EXT4_MB_DELALLOC_RESERVED;
+
 	ac = kmem_cache_alloc(ext4_ac_cachep, GFP_NOFS);
 	if (!ac) {
+		ar->len = 0;
 		*errp = -ENOMEM;
-		return 0;
+		goto out1;
 	}
 
 	ext4_mb_poll_new_transaction(sb, handle);
@@ -4037,12 +4214,11 @@ ext4_fsblk_t ext4_mb_new_blocks(handle_t *handle,
 	*errp = ext4_mb_initialize_context(ac, ar);
 	if (*errp) {
 		ar->len = 0;
-		goto out;
+		goto out2;
 	}
 
 	ac->ac_op = EXT4_MB_HISTORY_PREALLOC;
 	if (!ext4_mb_use_preallocated(ac)) {
-
 		ac->ac_op = EXT4_MB_HISTORY_ALLOC;
 		ext4_mb_normalize_request(ac, ar);
 repeat:
@@ -4085,11 +4261,12 @@ repeat:
 
 	ext4_mb_release_context(ac);
 
-out:
+out2:
+	kmem_cache_free(ext4_ac_cachep, ac);
+out1:
 	if (ar->len < inquota)
 		DQUOT_FREE_BLOCK(ar->inode, inquota - ar->len);
 
-	kmem_cache_free(ext4_ac_cachep, ac);
 	return block;
 }
 static void ext4_mb_poll_new_transaction(struct super_block *sb,
@@ -4242,7 +4419,7 @@ do_more:
 		overflow = bit + count - EXT4_BLOCKS_PER_GROUP(sb);
 		count -= overflow;
 	}
-	bitmap_bh = read_block_bitmap(sb, block_group);
+	bitmap_bh = ext4_read_block_bitmap(sb, block_group);
 	if (!bitmap_bh)
 		goto error_return;
 	gdp = ext4_get_group_desc(sb, block_group, &gd_bh);
@@ -4309,10 +4486,9 @@ do_more:
 		ext4_mb_free_metadata(handle, &e4b, block_group, bit, count);
 	} else {
 		ext4_lock_group(sb, block_group);
-		err = mb_free_blocks(inode, &e4b, bit, count);
+		mb_free_blocks(inode, &e4b, bit, count);
 		ext4_mb_return_to_preallocation(inode, &e4b, block, count);
 		ext4_unlock_group(sb, block_group);
-		BUG_ON(err != 0);
 	}
 
 	spin_lock(sb_bgl_lock(sbi, block_group));
@@ -4321,6 +4497,13 @@ do_more:
 	spin_unlock(sb_bgl_lock(sbi, block_group));
 	percpu_counter_add(&sbi->s_freeblocks_counter, count);
 
+	if (sbi->s_log_groups_per_flex) {
+		ext4_group_t flex_group = ext4_flex_group(sbi, block_group);
+		spin_lock(sb_bgl_lock(sbi, flex_group));
+		sbi->s_flex_groups[flex_group].free_blocks += count;
+		spin_unlock(sb_bgl_lock(sbi, flex_group));
+	}
+
 	ext4_mb_release_desc(&e4b);
 
 	*freed += count;
diff --git a/fs/ext4/namei.c b/fs/ext4/namei.c
index ab16beaa830..387ad98350c 100644
--- a/fs/ext4/namei.c
+++ b/fs/ext4/namei.c
@@ -183,6 +183,16 @@ static int ext4_dx_add_entry(handle_t *handle, struct dentry *dentry,
 			     struct inode *inode);
 
 /*
+ * p is at least 6 bytes before the end of page
+ */
+static inline struct ext4_dir_entry_2 *
+ext4_next_entry(struct ext4_dir_entry_2 *p)
+{
+	return (struct ext4_dir_entry_2 *)((char *)p +
+		ext4_rec_len_from_disk(p->rec_len));
+}
+
+/*
  * Future: use high four bits of block for coalesce-on-delete flags
  * Mask them off for now.
  */
@@ -231,13 +241,13 @@ static inline unsigned dx_root_limit (struct inode *dir, unsigned infosize)
 {
 	unsigned entry_space = dir->i_sb->s_blocksize - EXT4_DIR_REC_LEN(1) -
 		EXT4_DIR_REC_LEN(2) - infosize;
-	return 0? 20: entry_space / sizeof(struct dx_entry);
+	return entry_space / sizeof(struct dx_entry);
 }
 
 static inline unsigned dx_node_limit (struct inode *dir)
 {
 	unsigned entry_space = dir->i_sb->s_blocksize - EXT4_DIR_REC_LEN(0);
-	return 0? 22: entry_space / sizeof(struct dx_entry);
+	return entry_space / sizeof(struct dx_entry);
 }
 
 /*
@@ -554,15 +564,6 @@ static int ext4_htree_next_block(struct inode *dir, __u32 hash,
 
 
 /*
- * p is at least 6 bytes before the end of page
- */
-static inline struct ext4_dir_entry_2 *ext4_next_entry(struct ext4_dir_entry_2 *p)
-{
-	return (struct ext4_dir_entry_2 *)((char *)p +
-		ext4_rec_len_from_disk(p->rec_len));
-}
-
-/*
  * This function fills a red-black tree with information from a
  * directory block.  It returns the number directory entries loaded
  * into the tree.  If there is an error it is returned in err.
@@ -993,19 +994,21 @@ static struct buffer_head * ext4_dx_find_entry(struct dentry *dentry,
 		de = (struct ext4_dir_entry_2 *) bh->b_data;
 		top = (struct ext4_dir_entry_2 *) ((char *) de + sb->s_blocksize -
 				       EXT4_DIR_REC_LEN(0));
-		for (; de < top; de = ext4_next_entry(de))
-		if (ext4_match (namelen, name, de)) {
-			if (!ext4_check_dir_entry("ext4_find_entry",
-						  dir, de, bh,
-				  (block<<EXT4_BLOCK_SIZE_BITS(sb))
-					  +((char *)de - bh->b_data))) {
-				brelse (bh);
+		for (; de < top; de = ext4_next_entry(de)) {
+			int off = (block << EXT4_BLOCK_SIZE_BITS(sb))
+				  + ((char *) de - bh->b_data);
+
+			if (!ext4_check_dir_entry(__func__, dir, de, bh, off)) {
+				brelse(bh);
 				*err = ERR_BAD_DX_DIR;
 				goto errout;
 			}
-			*res_dir = de;
-			dx_release (frames);
-			return bh;
+
+			if (ext4_match(namelen, name, de)) {
+				*res_dir = de;
+				dx_release(frames);
+				return bh;
+			}
 		}
 		brelse (bh);
 		/* Check to see if we should continue to search */
diff --git a/fs/ext4/resize.c b/fs/ext4/resize.c
index 9ff7b1c0423..f000fbe2cd9 100644
--- a/fs/ext4/resize.c
+++ b/fs/ext4/resize.c
@@ -866,6 +866,15 @@ int ext4_group_add(struct super_block *sb, struct ext4_new_group_data *input)
 	gdp->bg_checksum = ext4_group_desc_csum(sbi, input->group, gdp);
 
 	/*
+	 * We can allocate memory for mb_alloc based on the new group
+	 * descriptor
+	 */
+	if (test_opt(sb, MBALLOC)) {
+		err = ext4_mb_add_more_groupinfo(sb, input->group, gdp);
+		if (err)
+			goto exit_journal;
+	}
+	/*
 	 * Make the new blocks and inodes valid next.  We do this before
 	 * increasing the group count so that once the group is enabled,
 	 * all of its blocks and inodes are already valid.
@@ -957,6 +966,8 @@ int ext4_group_extend(struct super_block *sb, struct ext4_super_block *es,
 	handle_t *handle;
 	int err;
 	unsigned long freed_blocks;
+	ext4_group_t group;
+	struct ext4_group_info *grp;
 
 	/* We don't need to worry about locking wrt other resizers just
 	 * yet: we're going to revalidate es->s_blocks_count after
@@ -988,7 +999,7 @@ int ext4_group_extend(struct super_block *sb, struct ext4_super_block *es,
 	}
 
 	/* Handle the remaining blocks in the last group only. */
-	ext4_get_group_no_and_offset(sb, o_blocks_count, NULL, &last);
+	ext4_get_group_no_and_offset(sb, o_blocks_count, &group, &last);
 
 	if (last == 0) {
 		ext4_warning(sb, __func__,
@@ -1060,6 +1071,45 @@ int ext4_group_extend(struct super_block *sb, struct ext4_super_block *es,
 		   o_blocks_count + add);
 	if ((err = ext4_journal_stop(handle)))
 		goto exit_put;
+
+	/*
+	 * Mark mballoc pages as not up to date so that they will be updated
+	 * next time they are loaded by ext4_mb_load_buddy.
+	 */
+	if (test_opt(sb, MBALLOC)) {
+		struct ext4_sb_info *sbi = EXT4_SB(sb);
+		struct inode *inode = sbi->s_buddy_cache;
+		int blocks_per_page;
+		int block;
+		int pnum;
+		struct page *page;
+
+		/* Set buddy page as not up to date */
+		blocks_per_page = PAGE_CACHE_SIZE / sb->s_blocksize;
+		block = group * 2;
+		pnum = block / blocks_per_page;
+		page = find_get_page(inode->i_mapping, pnum);
+		if (page != NULL) {
+			ClearPageUptodate(page);
+			page_cache_release(page);
+		}
+
+		/* Set bitmap page as not up to date */
+		block++;
+		pnum = block / blocks_per_page;
+		page = find_get_page(inode->i_mapping, pnum);
+		if (page != NULL) {
+			ClearPageUptodate(page);
+			page_cache_release(page);
+		}
+
+		/* Get the info on the last group */
+		grp = ext4_get_group_info(sb, group);
+
+		/* Update free blocks in group info */
+		ext4_mb_update_group_info(grp, add);
+	}
+
 	if (test_opt(sb, DEBUG))
 		printk(KERN_DEBUG "EXT4-fs: extended group to %llu blocks\n",
 		       ext4_blocks_count(es));
diff --git a/fs/ext4/super.c b/fs/ext4/super.c
index cb96f127c36..1cb371dcd60 100644
--- a/fs/ext4/super.c
+++ b/fs/ext4/super.c
@@ -506,6 +506,7 @@ static void ext4_put_super (struct super_block * sb)
 	ext4_ext_release(sb);
 	ext4_xattr_put_super(sb);
 	jbd2_journal_destroy(sbi->s_journal);
+	sbi->s_journal = NULL;
 	if (!(sb->s_flags & MS_RDONLY)) {
 		EXT4_CLEAR_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_RECOVER);
 		es->s_state = cpu_to_le16(sbi->s_mount_state);
@@ -517,6 +518,7 @@ static void ext4_put_super (struct super_block * sb)
 	for (i = 0; i < sbi->s_gdb_count; i++)
 		brelse(sbi->s_group_desc[i]);
 	kfree(sbi->s_group_desc);
+	kfree(sbi->s_flex_groups);
 	percpu_counter_destroy(&sbi->s_freeblocks_counter);
 	percpu_counter_destroy(&sbi->s_freeinodes_counter);
 	percpu_counter_destroy(&sbi->s_dirs_counter);
@@ -571,6 +573,12 @@ static struct inode *ext4_alloc_inode(struct super_block *sb)
 	memset(&ei->i_cached_extent, 0, sizeof(struct ext4_ext_cache));
 	INIT_LIST_HEAD(&ei->i_prealloc_list);
 	spin_lock_init(&ei->i_prealloc_lock);
+	jbd2_journal_init_jbd_inode(&ei->jinode, &ei->vfs_inode);
+	ei->i_reserved_data_blocks = 0;
+	ei->i_reserved_meta_blocks = 0;
+	ei->i_allocated_meta_blocks = 0;
+	ei->i_delalloc_reserved_flag = 0;
+	spin_lock_init(&(ei->i_block_reservation_lock));
 	return &ei->vfs_inode;
 }
 
@@ -635,6 +643,8 @@ static void ext4_clear_inode(struct inode *inode)
 	EXT4_I(inode)->i_block_alloc_info = NULL;
 	if (unlikely(rsv))
 		kfree(rsv);
+	jbd2_journal_release_jbd_inode(EXT4_SB(inode->i_sb)->s_journal,
+				       &EXT4_I(inode)->jinode);
 }
 
 static inline void ext4_show_quota_options(struct seq_file *seq, struct super_block *sb)
@@ -671,7 +681,6 @@ static int ext4_show_options(struct seq_file *seq, struct vfsmount *vfs)
 	unsigned long def_mount_opts;
 	struct super_block *sb = vfs->mnt_sb;
 	struct ext4_sb_info *sbi = EXT4_SB(sb);
-	journal_t *journal = sbi->s_journal;
 	struct ext4_super_block *es = sbi->s_es;
 
 	def_mount_opts = le32_to_cpu(es->s_default_mount_opts);
@@ -747,6 +756,9 @@ static int ext4_show_options(struct seq_file *seq, struct vfsmount *vfs)
 		seq_puts(seq, ",nomballoc");
 	if (test_opt(sb, I_VERSION))
 		seq_puts(seq, ",i_version");
+	if (!test_opt(sb, DELALLOC))
+		seq_puts(seq, ",nodelalloc");
+
 
 	if (sbi->s_stripe)
 		seq_printf(seq, ",stripe=%lu", sbi->s_stripe);
@@ -894,7 +906,7 @@ enum {
 	Opt_jqfmt_vfsold, Opt_jqfmt_vfsv0, Opt_quota, Opt_noquota,
 	Opt_ignore, Opt_barrier, Opt_err, Opt_resize, Opt_usrquota,
 	Opt_grpquota, Opt_extents, Opt_noextents, Opt_i_version,
-	Opt_mballoc, Opt_nomballoc, Opt_stripe,
+	Opt_mballoc, Opt_nomballoc, Opt_stripe, Opt_delalloc, Opt_nodelalloc,
 };
 
 static match_table_t tokens = {
@@ -953,6 +965,8 @@ static match_table_t tokens = {
 	{Opt_nomballoc, "nomballoc"},
 	{Opt_stripe, "stripe=%u"},
 	{Opt_resize, "resize"},
+	{Opt_delalloc, "delalloc"},
+	{Opt_nodelalloc, "nodelalloc"},
 	{Opt_err, NULL},
 };
 
@@ -990,6 +1004,7 @@ static int parse_options (char *options, struct super_block *sb,
 	int qtype, qfmt;
 	char *qname;
 #endif
+	ext4_fsblk_t last_block;
 
 	if (!options)
 		return 1;
@@ -1309,15 +1324,39 @@ set_qf_format:
 			clear_opt(sbi->s_mount_opt, NOBH);
 			break;
 		case Opt_extents:
+			if (!EXT4_HAS_INCOMPAT_FEATURE(sb,
+					EXT4_FEATURE_INCOMPAT_EXTENTS)) {
+				ext4_warning(sb, __func__,
+					"extents feature not enabled "
+					"on this filesystem, use tune2fs\n");
+				return 0;
+			}
 			set_opt (sbi->s_mount_opt, EXTENTS);
 			break;
 		case Opt_noextents:
+			/*
+			 * When e2fsprogs support resizing an already existing
+			 * ext3 file system to greater than 2**32 we need to
+			 * add support to block allocator to handle growing
+			 * already existing block  mapped inode so that blocks
+			 * allocated for them fall within 2**32
+			 */
+			last_block = ext4_blocks_count(sbi->s_es) - 1;
+			if (last_block  > 0xffffffffULL) {
+				printk(KERN_ERR "EXT4-fs: Filesystem too "
+						"large to mount with "
+						"-o noextents options\n");
+				return 0;
+			}
 			clear_opt (sbi->s_mount_opt, EXTENTS);
 			break;
 		case Opt_i_version:
 			set_opt(sbi->s_mount_opt, I_VERSION);
 			sb->s_flags |= MS_I_VERSION;
 			break;
+		case Opt_nodelalloc:
+			clear_opt(sbi->s_mount_opt, DELALLOC);
+			break;
 		case Opt_mballoc:
 			set_opt(sbi->s_mount_opt, MBALLOC);
 			break;
@@ -1331,6 +1370,9 @@ set_qf_format:
 				return 0;
 			sbi->s_stripe = option;
 			break;
+		case Opt_delalloc:
+			set_opt(sbi->s_mount_opt, DELALLOC);
+			break;
 		default:
 			printk (KERN_ERR
 				"EXT4-fs: Unrecognized mount option \"%s\" "
@@ -1443,6 +1485,54 @@ static int ext4_setup_super(struct super_block *sb, struct ext4_super_block *es,
 	return res;
 }
 
+static int ext4_fill_flex_info(struct super_block *sb)
+{
+	struct ext4_sb_info *sbi = EXT4_SB(sb);
+	struct ext4_group_desc *gdp = NULL;
+	struct buffer_head *bh;
+	ext4_group_t flex_group_count;
+	ext4_group_t flex_group;
+	int groups_per_flex = 0;
+	__u64 block_bitmap = 0;
+	int i;
+
+	if (!sbi->s_es->s_log_groups_per_flex) {
+		sbi->s_log_groups_per_flex = 0;
+		return 1;
+	}
+
+	sbi->s_log_groups_per_flex = sbi->s_es->s_log_groups_per_flex;
+	groups_per_flex = 1 << sbi->s_log_groups_per_flex;
+
+	flex_group_count = (sbi->s_groups_count + groups_per_flex - 1) /
+		groups_per_flex;
+	sbi->s_flex_groups = kmalloc(flex_group_count *
+				     sizeof(struct flex_groups), GFP_KERNEL);
+	if (sbi->s_flex_groups == NULL) {
+		printk(KERN_ERR "EXT4-fs: not enough memory\n");
+		goto failed;
+	}
+	memset(sbi->s_flex_groups, 0, flex_group_count *
+	       sizeof(struct flex_groups));
+
+	gdp = ext4_get_group_desc(sb, 1, &bh);
+	block_bitmap = ext4_block_bitmap(sb, gdp) - 1;
+
+	for (i = 0; i < sbi->s_groups_count; i++) {
+		gdp = ext4_get_group_desc(sb, i, &bh);
+
+		flex_group = ext4_flex_group(sbi, i);
+		sbi->s_flex_groups[flex_group].free_inodes +=
+			le16_to_cpu(gdp->bg_free_inodes_count);
+		sbi->s_flex_groups[flex_group].free_blocks +=
+			le16_to_cpu(gdp->bg_free_blocks_count);
+	}
+
+	return 1;
+failed:
+	return 0;
+}
+
 __le16 ext4_group_desc_csum(struct ext4_sb_info *sbi, __u32 block_group,
 			    struct ext4_group_desc *gdp)
 {
@@ -1810,8 +1900,8 @@ static unsigned long ext4_get_stripe_size(struct ext4_sb_info *sbi)
 }
 
 static int ext4_fill_super (struct super_block *sb, void *data, int silent)
-				__releases(kernel_sem)
-				__acquires(kernel_sem)
+				__releases(kernel_lock)
+				__acquires(kernel_lock)
 
 {
 	struct buffer_head * bh;
@@ -1851,11 +1941,6 @@ static int ext4_fill_super (struct super_block *sb, void *data, int silent)
 		goto out_fail;
 	}
 
-	if (!sb_set_blocksize(sb, blocksize)) {
-		printk(KERN_ERR "EXT4-fs: bad blocksize %d.\n", blocksize);
-		goto out_fail;
-	}
-
 	/*
 	 * The ext4 superblock will not be buffer aligned for other than 1kB
 	 * block sizes.  We need to calculate the offset from buffer start.
@@ -1919,15 +2004,28 @@ static int ext4_fill_super (struct super_block *sb, void *data, int silent)
 
 	/*
 	 * turn on extents feature by default in ext4 filesystem
-	 * User -o noextents to turn it off
+	 * only if feature flag already set by mkfs or tune2fs.
+	 * Use -o noextents to turn it off
 	 */
-	set_opt(sbi->s_mount_opt, EXTENTS);
+	if (EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_EXTENTS))
+		set_opt(sbi->s_mount_opt, EXTENTS);
+	else
+		ext4_warning(sb, __func__,
+			"extents feature not enabled on this filesystem, "
+			"use tune2fs.\n");
 	/*
-	 * turn on mballoc feature by default in ext4 filesystem
-	 * User -o nomballoc to turn it off
+	 * turn on mballoc code by default in ext4 filesystem
+	 * Use -o nomballoc to turn it off
 	 */
 	set_opt(sbi->s_mount_opt, MBALLOC);
 
+	/*
+	 * enable delayed allocation by default
+	 * Use -o nodelalloc to turn it off
+	 */
+	set_opt(sbi->s_mount_opt, DELALLOC);
+
+
 	if (!parse_options ((char *) data, sb, &journal_inum, &journal_devnum,
 			    NULL, 0))
 		goto failed_mount;
@@ -2138,6 +2236,14 @@ static int ext4_fill_super (struct super_block *sb, void *data, int silent)
 		printk(KERN_ERR "EXT4-fs: group descriptors corrupted!\n");
 		goto failed_mount2;
 	}
+	if (EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_FLEX_BG))
+		if (!ext4_fill_flex_info(sb)) {
+			printk(KERN_ERR
+			       "EXT4-fs: unable to initialize "
+			       "flex_bg meta info!\n");
+			goto failed_mount2;
+		}
+
 	sbi->s_gdb_count = db_count;
 	get_random_bytes(&sbi->s_next_generation, sizeof(u32));
 	spin_lock_init(&sbi->s_next_gen_lock);
@@ -2358,6 +2464,13 @@ static int ext4_fill_super (struct super_block *sb, void *data, int silent)
 		test_opt(sb,DATA_FLAGS) == EXT4_MOUNT_ORDERED_DATA ? "ordered":
 		"writeback");
 
+	if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_JOURNAL_DATA) {
+		printk(KERN_WARNING "EXT4-fs: Ignoring delalloc option - "
+				"requested data journaling mode\n");
+		clear_opt(sbi->s_mount_opt, DELALLOC);
+	} else if (test_opt(sb, DELALLOC))
+		printk(KERN_INFO "EXT4-fs: delayed allocation enabled\n");
+
 	ext4_ext_init(sb);
 	ext4_mb_init(sb, needs_recovery);
 
@@ -2372,6 +2485,7 @@ cantfind_ext4:
 
 failed_mount4:
 	jbd2_journal_destroy(sbi->s_journal);
+	sbi->s_journal = NULL;
 failed_mount3:
 	percpu_counter_destroy(&sbi->s_freeblocks_counter);
 	percpu_counter_destroy(&sbi->s_freeinodes_counter);
@@ -3325,7 +3439,7 @@ static ssize_t ext4_quota_write(struct super_block *sb, int type,
 			err = ext4_journal_dirty_metadata(handle, bh);
 		else {
 			/* Always do at least ordered writes for quotas */
-			err = ext4_journal_dirty_data(handle, bh);
+			err = ext4_jbd2_file_inode(handle, inode);
 			mark_buffer_dirty(bh);
 		}
 		brelse(bh);
@@ -3337,8 +3451,10 @@ static ssize_t ext4_quota_write(struct super_block *sb, int type,
 		blk++;
 	}
 out:
-	if (len == towrite)
+	if (len == towrite) {
+		mutex_unlock(&inode->i_mutex);
 		return err;
+	}
 	if (inode->i_size < off+len-towrite) {
 		i_size_write(inode, off+len-towrite);
 		EXT4_I(inode)->i_disksize = inode->i_size;
diff --git a/fs/ext4/xattr.c b/fs/ext4/xattr.c
index ff08633f398..93c5fdcdad2 100644
--- a/fs/ext4/xattr.c
+++ b/fs/ext4/xattr.c
@@ -810,7 +810,7 @@ inserted:
 			/* We need to allocate a new block */
 			ext4_fsblk_t goal = ext4_group_first_block_no(sb,
 						EXT4_I(inode)->i_block_group);
-			ext4_fsblk_t block = ext4_new_block(handle, inode,
+			ext4_fsblk_t block = ext4_new_meta_block(handle, inode,
 							goal, &error);
 			if (error)
 				goto cleanup;
diff --git a/fs/ext4/xattr_trusted.c b/fs/ext4/xattr_trusted.c
index fff33382cad..ac1a52cf2a3 100644
--- a/fs/ext4/xattr_trusted.c
+++ b/fs/ext4/xattr_trusted.c
@@ -13,13 +13,11 @@
 #include "ext4.h"
 #include "xattr.h"
 
-#define XATTR_TRUSTED_PREFIX "trusted."
-
 static size_t
 ext4_xattr_trusted_list(struct inode *inode, char *list, size_t list_size,
 			const char *name, size_t name_len)
 {
-	const size_t prefix_len = sizeof(XATTR_TRUSTED_PREFIX)-1;
+	const size_t prefix_len = XATTR_TRUSTED_PREFIX_LEN;
 	const size_t total_len = prefix_len + name_len + 1;
 
 	if (!capable(CAP_SYS_ADMIN))
diff --git a/fs/ext4/xattr_user.c b/fs/ext4/xattr_user.c
index 67be723fcc4..d91aa61b42a 100644
--- a/fs/ext4/xattr_user.c
+++ b/fs/ext4/xattr_user.c
@@ -12,13 +12,11 @@
 #include "ext4.h"
 #include "xattr.h"
 
-#define XATTR_USER_PREFIX "user."
-
 static size_t
 ext4_xattr_user_list(struct inode *inode, char *list, size_t list_size,
 		     const char *name, size_t name_len)
 {
-	const size_t prefix_len = sizeof(XATTR_USER_PREFIX)-1;
+	const size_t prefix_len = XATTR_USER_PREFIX_LEN;
 	const size_t total_len = prefix_len + name_len + 1;
 
 	if (!test_opt(inode->i_sb, XATTR_USER))
diff --git a/fs/fat/cache.c b/fs/fat/cache.c
index fda25479af2..3a9ecac8d61 100644
--- a/fs/fat/cache.c
+++ b/fs/fat/cache.c
@@ -61,7 +61,7 @@ void fat_cache_destroy(void)
 
 static inline struct fat_cache *fat_cache_alloc(struct inode *inode)
 {
-	return kmem_cache_alloc(fat_cache_cachep, GFP_KERNEL);
+	return kmem_cache_alloc(fat_cache_cachep, GFP_NOFS);
 }
 
 static inline void fat_cache_free(struct fat_cache *cache)
diff --git a/fs/fat/dir.c b/fs/fat/dir.c
index 486725ee99a..34541d06e62 100644
--- a/fs/fat/dir.c
+++ b/fs/fat/dir.c
@@ -472,7 +472,7 @@ static int __fat_readdir(struct inode *inode, struct file *filp, void *dirent,
 	loff_t cpos;
 	int ret = 0;
 
-	lock_kernel();
+	lock_super(sb);
 
 	cpos = filp->f_pos;
 	/* Fake . and .. for the root directory. */
@@ -654,7 +654,7 @@ FillFailed:
 	if (unicode)
 		__putname(unicode);
 out:
-	unlock_kernel();
+	unlock_super(sb);
 	return ret;
 }
 
diff --git a/fs/fat/file.c b/fs/fat/file.c
index 771326b8047..c672df4036e 100644
--- a/fs/fat/file.c
+++ b/fs/fat/file.c
@@ -11,7 +11,6 @@
 #include <linux/mount.h>
 #include <linux/time.h>
 #include <linux/msdos_fs.h>
-#include <linux/smp_lock.h>
 #include <linux/buffer_head.h>
 #include <linux/writeback.h>
 #include <linux/backing-dev.h>
@@ -242,9 +241,7 @@ void fat_truncate(struct inode *inode)
 
 	nr_clusters = (inode->i_size + (cluster_size - 1)) >> sbi->cluster_bits;
 
-	lock_kernel();
 	fat_free(inode, nr_clusters);
-	unlock_kernel();
 	fat_flush_inodes(inode->i_sb, inode, NULL);
 }
 
@@ -310,8 +307,6 @@ int fat_setattr(struct dentry *dentry, struct iattr *attr)
 	int error = 0;
 	unsigned int ia_valid;
 
-	lock_kernel();
-
 	/*
 	 * Expand the file. Since inode_setattr() updates ->i_size
 	 * before calling the ->truncate(), but FAT needs to fill the
@@ -366,7 +361,6 @@ int fat_setattr(struct dentry *dentry, struct iattr *attr)
 
 	error = inode_setattr(inode, attr);
 out:
-	unlock_kernel();
 	return error;
 }
 EXPORT_SYMBOL_GPL(fat_setattr);
diff --git a/fs/fat/inode.c b/fs/fat/inode.c
index 4e0a3dd9d67..46a4508ffd2 100644
--- a/fs/fat/inode.c
+++ b/fs/fat/inode.c
@@ -440,14 +440,13 @@ static void fat_delete_inode(struct inode *inode)
 
 static void fat_clear_inode(struct inode *inode)
 {
-	struct msdos_sb_info *sbi = MSDOS_SB(inode->i_sb);
+	struct super_block *sb = inode->i_sb;
+	struct msdos_sb_info *sbi = MSDOS_SB(sb);
 
-	lock_kernel();
 	spin_lock(&sbi->inode_hash_lock);
 	fat_cache_inval_inode(inode);
 	hlist_del_init(&MSDOS_I(inode)->i_fat_hash);
 	spin_unlock(&sbi->inode_hash_lock);
-	unlock_kernel();
 }
 
 static void fat_write_super(struct super_block *sb)
@@ -485,7 +484,7 @@ static struct kmem_cache *fat_inode_cachep;
 static struct inode *fat_alloc_inode(struct super_block *sb)
 {
 	struct msdos_inode_info *ei;
-	ei = kmem_cache_alloc(fat_inode_cachep, GFP_KERNEL);
+	ei = kmem_cache_alloc(fat_inode_cachep, GFP_NOFS);
 	if (!ei)
 		return NULL;
 	return &ei->vfs_inode;
@@ -567,7 +566,7 @@ retry:
 	if (inode->i_ino == MSDOS_ROOT_INO || !i_pos)
 		return 0;
 
-	lock_kernel();
+	lock_super(sb);
 	bh = sb_bread(sb, i_pos >> sbi->dir_per_block_bits);
 	if (!bh) {
 		printk(KERN_ERR "FAT: unable to read inode block "
@@ -579,7 +578,7 @@ retry:
 	if (i_pos != MSDOS_I(inode)->i_pos) {
 		spin_unlock(&sbi->inode_hash_lock);
 		brelse(bh);
-		unlock_kernel();
+		unlock_super(sb);
 		goto retry;
 	}
 
@@ -606,7 +605,7 @@ retry:
 		err = sync_dirty_buffer(bh);
 	brelse(bh);
 out:
-	unlock_kernel();
+	unlock_super(sb);
 	return err;
 }
 
@@ -736,6 +735,7 @@ fat_encode_fh(struct dentry *de, __u32 *fh, int *lenp, int connectable)
 
 static struct dentry *fat_get_parent(struct dentry *child)
 {
+	struct super_block *sb = child->d_sb;
 	struct buffer_head *bh;
 	struct msdos_dir_entry *de;
 	loff_t i_pos;
@@ -743,14 +743,14 @@ static struct dentry *fat_get_parent(struct dentry *child)
 	struct inode *inode;
 	int err;
 
-	lock_kernel();
+	lock_super(sb);
 
 	err = fat_get_dotdot_entry(child->d_inode, &bh, &de, &i_pos);
 	if (err) {
 		parent = ERR_PTR(err);
 		goto out;
 	}
-	inode = fat_build_inode(child->d_sb, de, i_pos);
+	inode = fat_build_inode(sb, de, i_pos);
 	brelse(bh);
 	if (IS_ERR(inode)) {
 		parent = ERR_CAST(inode);
@@ -762,7 +762,7 @@ static struct dentry *fat_get_parent(struct dentry *child)
 		parent = ERR_PTR(-ENOMEM);
 	}
 out:
-	unlock_kernel();
+	unlock_super(sb);
 
 	return parent;
 }
@@ -1172,6 +1172,12 @@ int fat_fill_super(struct super_block *sb, void *data, int silent,
 	long error;
 	char buf[50];
 
+	/*
+	 * GFP_KERNEL is ok here, because while we do hold the
+	 * supeblock lock, memory pressure can't call back into
+	 * the filesystem, since we're only just about to mount
+	 * it and have no inodes etc active!
+	 */
 	sbi = kzalloc(sizeof(struct msdos_sb_info), GFP_KERNEL);
 	if (!sbi)
 		return -ENOMEM;
diff --git a/fs/fcntl.c b/fs/fcntl.c
index bfd776509a7..330a7d78259 100644
--- a/fs/fcntl.c
+++ b/fs/fcntl.c
@@ -12,7 +12,6 @@
 #include <linux/fdtable.h>
 #include <linux/capability.h>
 #include <linux/dnotify.h>
-#include <linux/smp_lock.h>
 #include <linux/slab.h>
 #include <linux/module.h>
 #include <linux/security.h>
@@ -227,7 +226,6 @@ static int setfl(int fd, struct file * filp, unsigned long arg)
 	if (error)
 		return error;
 
-	lock_kernel();
 	if ((arg ^ filp->f_flags) & FASYNC) {
 		if (filp->f_op && filp->f_op->fasync) {
 			error = filp->f_op->fasync(fd, filp, (arg & FASYNC) != 0);
@@ -238,7 +236,6 @@ static int setfl(int fd, struct file * filp, unsigned long arg)
 
 	filp->f_flags = (arg & SETFL_MASK) | (filp->f_flags & ~SETFL_MASK);
  out:
-	unlock_kernel();
 	return error;
 }
 
diff --git a/fs/fs-writeback.c b/fs/fs-writeback.c
index ae45f77765c..25adfc3c693 100644
--- a/fs/fs-writeback.c
+++ b/fs/fs-writeback.c
@@ -424,8 +424,6 @@ __writeback_single_inode(struct inode *inode, struct writeback_control *wbc)
  * WB_SYNC_HOLD is a hack for sys_sync(): reattach the inode to sb->s_dirty so
  * that it can be located for waiting on in __writeback_single_inode().
  *
- * Called under inode_lock.
- *
  * If `bdi' is non-zero then we're being asked to writeback a specific queue.
  * This function assumes that the blockdev superblock's inodes are backed by
  * a variety of queues, so all inodes are searched.  For other superblocks,
@@ -441,11 +439,12 @@ __writeback_single_inode(struct inode *inode, struct writeback_control *wbc)
  * on the writer throttling path, and we get decent balancing between many
  * throttled threads: we don't want them all piling up on inode_sync_wait.
  */
-static void
-sync_sb_inodes(struct super_block *sb, struct writeback_control *wbc)
+void generic_sync_sb_inodes(struct super_block *sb,
+				struct writeback_control *wbc)
 {
 	const unsigned long start = jiffies;	/* livelock avoidance */
 
+	spin_lock(&inode_lock);
 	if (!wbc->for_kupdate || list_empty(&sb->s_io))
 		queue_io(sb, wbc->older_than_this);
 
@@ -524,8 +523,16 @@ sync_sb_inodes(struct super_block *sb, struct writeback_control *wbc)
 		if (!list_empty(&sb->s_more_io))
 			wbc->more_io = 1;
 	}
+	spin_unlock(&inode_lock);
 	return;		/* Leave any unwritten inodes on s_io */
 }
+EXPORT_SYMBOL_GPL(generic_sync_sb_inodes);
+
+static void sync_sb_inodes(struct super_block *sb,
+				struct writeback_control *wbc)
+{
+	generic_sync_sb_inodes(sb, wbc);
+}
 
 /*
  * Start writeback of dirty pagecache data against all unlocked inodes.
@@ -565,11 +572,8 @@ restart:
 			 * be unmounted by the time it is released.
 			 */
 			if (down_read_trylock(&sb->s_umount)) {
-				if (sb->s_root) {
-					spin_lock(&inode_lock);
+				if (sb->s_root)
 					sync_sb_inodes(sb, wbc);
-					spin_unlock(&inode_lock);
-				}
 				up_read(&sb->s_umount);
 			}
 			spin_lock(&sb_lock);
@@ -607,9 +611,7 @@ void sync_inodes_sb(struct super_block *sb, int wait)
 			(inodes_stat.nr_inodes - inodes_stat.nr_unused) +
 			nr_dirty + nr_unstable;
 	wbc.nr_to_write += wbc.nr_to_write / 2;		/* Bit more for luck */
-	spin_lock(&inode_lock);
 	sync_sb_inodes(sb, &wbc);
-	spin_unlock(&inode_lock);
 }
 
 /*
diff --git a/fs/gfs2/Kconfig b/fs/gfs2/Kconfig
index 7f7947e3dfb..ab2f57e3fb8 100644
--- a/fs/gfs2/Kconfig
+++ b/fs/gfs2/Kconfig
@@ -14,23 +14,11 @@ config GFS2_FS
 	  GFS is perfect consistency -- changes made to the filesystem on one
 	  machine show up immediately on all other machines in the cluster.
 
-	  To use the GFS2 filesystem, you will need to enable one or more of
-	  the below locking modules. Documentation and utilities for GFS2 can
+	  To use the GFS2 filesystem in a cluster, you will need to enable
+	  the locking module below. Documentation and utilities for GFS2 can
 	  be found here: http://sources.redhat.com/cluster
 
-config GFS2_FS_LOCKING_NOLOCK
-	tristate "GFS2 \"nolock\" locking module"
-	depends on GFS2_FS
-	help
-	  Single node locking module for GFS2.
-
-	  Use this module if you want to use GFS2 on a single node without
-	  its clustering features. You can still take advantage of the
-	  large file support, and upgrade to running a full cluster later on
-	  if required.
-
-	  If you will only be using GFS2 in cluster mode, you do not need this
-	  module.
+	  The "nolock" lock module is now built in to GFS2 by default.
 
 config GFS2_FS_LOCKING_DLM
 	tristate "GFS2 DLM locking module"
diff --git a/fs/gfs2/Makefile b/fs/gfs2/Makefile
index e2350df02a0..ec65851ec80 100644
--- a/fs/gfs2/Makefile
+++ b/fs/gfs2/Makefile
@@ -5,6 +5,5 @@ gfs2-y := acl.o bmap.o daemon.o dir.o eaops.o eattr.o glock.o \
 	ops_fstype.o ops_inode.o ops_super.o quota.o \
 	recovery.o rgrp.o super.o sys.o trans.o util.o
 
-obj-$(CONFIG_GFS2_FS_LOCKING_NOLOCK) += locking/nolock/
 obj-$(CONFIG_GFS2_FS_LOCKING_DLM) += locking/dlm/
 
diff --git a/fs/gfs2/gfs2.h b/fs/gfs2/gfs2.h
index 3bb11c0f8b5..ef606e3a5cf 100644
--- a/fs/gfs2/gfs2.h
+++ b/fs/gfs2/gfs2.h
@@ -16,11 +16,6 @@ enum {
 };
 
 enum {
-	NO_WAIT = 0,
-	WAIT = 1,
-};
-
-enum {
 	NO_FORCE = 0,
 	FORCE = 1,
 };
diff --git a/fs/gfs2/glock.c b/fs/gfs2/glock.c
index d636b3e80f5..13391e54661 100644
--- a/fs/gfs2/glock.c
+++ b/fs/gfs2/glock.c
@@ -45,21 +45,19 @@ struct gfs2_gl_hash_bucket {
         struct hlist_head hb_list;
 };
 
-struct glock_iter {
-	int hash;                     /* hash bucket index         */
-	struct gfs2_sbd *sdp;         /* incore superblock         */
-	struct gfs2_glock *gl;        /* current glock struct      */
-	struct seq_file *seq;         /* sequence file for debugfs */
-	char string[512];             /* scratch space             */
+struct gfs2_glock_iter {
+	int hash;			/* hash bucket index         */
+	struct gfs2_sbd *sdp;		/* incore superblock         */
+	struct gfs2_glock *gl;		/* current glock struct      */
+	char string[512];		/* scratch space             */
 };
 
 typedef void (*glock_examiner) (struct gfs2_glock * gl);
 
 static int gfs2_dump_lockstate(struct gfs2_sbd *sdp);
-static int dump_glock(struct glock_iter *gi, struct gfs2_glock *gl);
-static void gfs2_glock_xmote_th(struct gfs2_glock *gl, struct gfs2_holder *gh);
-static void gfs2_glock_drop_th(struct gfs2_glock *gl);
-static void run_queue(struct gfs2_glock *gl);
+static int __dump_glock(struct seq_file *seq, const struct gfs2_glock *gl);
+#define GLOCK_BUG_ON(gl,x) do { if (unlikely(x)) { __dump_glock(NULL, gl); BUG(); } } while(0)
+static void do_xmote(struct gfs2_glock *gl, struct gfs2_holder *gh, unsigned int target);
 
 static DECLARE_RWSEM(gfs2_umount_flush_sem);
 static struct dentry *gfs2_root;
@@ -123,33 +121,6 @@ static inline rwlock_t *gl_lock_addr(unsigned int x)
 #endif
 
 /**
- * relaxed_state_ok - is a requested lock compatible with the current lock mode?
- * @actual: the current state of the lock
- * @requested: the lock state that was requested by the caller
- * @flags: the modifier flags passed in by the caller
- *
- * Returns: 1 if the locks are compatible, 0 otherwise
- */
-
-static inline int relaxed_state_ok(unsigned int actual, unsigned requested,
-				   int flags)
-{
-	if (actual == requested)
-		return 1;
-
-	if (flags & GL_EXACT)
-		return 0;
-
-	if (actual == LM_ST_EXCLUSIVE && requested == LM_ST_SHARED)
-		return 1;
-
-	if (actual != LM_ST_UNLOCKED && (flags & LM_FLAG_ANY))
-		return 1;
-
-	return 0;
-}
-
-/**
  * gl_hash() - Turn glock number into hash bucket number
  * @lock: The glock number
  *
@@ -182,7 +153,7 @@ static void glock_free(struct gfs2_glock *gl)
 	struct gfs2_sbd *sdp = gl->gl_sbd;
 	struct inode *aspace = gl->gl_aspace;
 
-	if (likely(!test_bit(SDF_SHUTDOWN, &sdp->sd_flags)))
+	if (sdp->sd_lockstruct.ls_ops->lm_put_lock)
 		sdp->sd_lockstruct.ls_ops->lm_put_lock(gl->gl_lock);
 
 	if (aspace)
@@ -211,17 +182,14 @@ static void gfs2_glock_hold(struct gfs2_glock *gl)
 int gfs2_glock_put(struct gfs2_glock *gl)
 {
 	int rv = 0;
-	struct gfs2_sbd *sdp = gl->gl_sbd;
 
 	write_lock(gl_lock_addr(gl->gl_hash));
 	if (atomic_dec_and_test(&gl->gl_ref)) {
 		hlist_del(&gl->gl_list);
 		write_unlock(gl_lock_addr(gl->gl_hash));
-		gfs2_assert(sdp, gl->gl_state == LM_ST_UNLOCKED);
-		gfs2_assert(sdp, list_empty(&gl->gl_reclaim));
-		gfs2_assert(sdp, list_empty(&gl->gl_holders));
-		gfs2_assert(sdp, list_empty(&gl->gl_waiters1));
-		gfs2_assert(sdp, list_empty(&gl->gl_waiters3));
+		GLOCK_BUG_ON(gl, gl->gl_state != LM_ST_UNLOCKED);
+		GLOCK_BUG_ON(gl, !list_empty(&gl->gl_reclaim));
+		GLOCK_BUG_ON(gl, !list_empty(&gl->gl_holders));
 		glock_free(gl);
 		rv = 1;
 		goto out;
@@ -281,22 +249,401 @@ static struct gfs2_glock *gfs2_glock_find(const struct gfs2_sbd *sdp,
 	return gl;
 }
 
+/**
+ * may_grant - check if its ok to grant a new lock
+ * @gl: The glock
+ * @gh: The lock request which we wish to grant
+ *
+ * Returns: true if its ok to grant the lock
+ */
+
+static inline int may_grant(const struct gfs2_glock *gl, const struct gfs2_holder *gh)
+{
+	const struct gfs2_holder *gh_head = list_entry(gl->gl_holders.next, const struct gfs2_holder, gh_list);
+	if ((gh->gh_state == LM_ST_EXCLUSIVE ||
+	     gh_head->gh_state == LM_ST_EXCLUSIVE) && gh != gh_head)
+		return 0;
+	if (gl->gl_state == gh->gh_state)
+		return 1;
+	if (gh->gh_flags & GL_EXACT)
+		return 0;
+	if (gl->gl_state == LM_ST_EXCLUSIVE) {
+		if (gh->gh_state == LM_ST_SHARED && gh_head->gh_state == LM_ST_SHARED)
+			return 1;
+		if (gh->gh_state == LM_ST_DEFERRED && gh_head->gh_state == LM_ST_DEFERRED)
+			return 1;
+	}
+	if (gl->gl_state != LM_ST_UNLOCKED && (gh->gh_flags & LM_FLAG_ANY))
+		return 1;
+	return 0;
+}
+
+static void gfs2_holder_wake(struct gfs2_holder *gh)
+{
+	clear_bit(HIF_WAIT, &gh->gh_iflags);
+	smp_mb__after_clear_bit();
+	wake_up_bit(&gh->gh_iflags, HIF_WAIT);
+}
+
+/**
+ * do_promote - promote as many requests as possible on the current queue
+ * @gl: The glock
+ * 
+ * Returns: true if there is a blocked holder at the head of the list
+ */
+
+static int do_promote(struct gfs2_glock *gl)
+{
+	const struct gfs2_glock_operations *glops = gl->gl_ops;
+	struct gfs2_holder *gh, *tmp;
+	int ret;
+
+restart:
+	list_for_each_entry_safe(gh, tmp, &gl->gl_holders, gh_list) {
+		if (test_bit(HIF_HOLDER, &gh->gh_iflags))
+			continue;
+		if (may_grant(gl, gh)) {
+			if (gh->gh_list.prev == &gl->gl_holders &&
+			    glops->go_lock) {
+				spin_unlock(&gl->gl_spin);
+				/* FIXME: eliminate this eventually */
+				ret = glops->go_lock(gh);
+				spin_lock(&gl->gl_spin);
+				if (ret) {
+					gh->gh_error = ret;
+					list_del_init(&gh->gh_list);
+					gfs2_holder_wake(gh);
+					goto restart;
+				}
+				set_bit(HIF_HOLDER, &gh->gh_iflags);
+				gfs2_holder_wake(gh);
+				goto restart;
+			}
+			set_bit(HIF_HOLDER, &gh->gh_iflags);
+			gfs2_holder_wake(gh);
+			continue;
+		}
+		if (gh->gh_list.prev == &gl->gl_holders)
+			return 1;
+		break;
+	}
+	return 0;
+}
+
+/**
+ * do_error - Something unexpected has happened during a lock request
+ *
+ */
+
+static inline void do_error(struct gfs2_glock *gl, const int ret)
+{
+	struct gfs2_holder *gh, *tmp;
+
+	list_for_each_entry_safe(gh, tmp, &gl->gl_holders, gh_list) {
+		if (test_bit(HIF_HOLDER, &gh->gh_iflags))
+			continue;
+		if (ret & LM_OUT_ERROR)
+			gh->gh_error = -EIO;
+		else if (gh->gh_flags & (LM_FLAG_TRY | LM_FLAG_TRY_1CB))
+			gh->gh_error = GLR_TRYFAILED;
+		else
+			continue;
+		list_del_init(&gh->gh_list);
+		gfs2_holder_wake(gh);
+	}
+}
+
+/**
+ * find_first_waiter - find the first gh that's waiting for the glock
+ * @gl: the glock
+ */
+
+static inline struct gfs2_holder *find_first_waiter(const struct gfs2_glock *gl)
+{
+	struct gfs2_holder *gh;
+
+	list_for_each_entry(gh, &gl->gl_holders, gh_list) {
+		if (!test_bit(HIF_HOLDER, &gh->gh_iflags))
+			return gh;
+	}
+	return NULL;
+}
+
+/**
+ * state_change - record that the glock is now in a different state
+ * @gl: the glock
+ * @new_state the new state
+ *
+ */
+
+static void state_change(struct gfs2_glock *gl, unsigned int new_state)
+{
+	int held1, held2;
+
+	held1 = (gl->gl_state != LM_ST_UNLOCKED);
+	held2 = (new_state != LM_ST_UNLOCKED);
+
+	if (held1 != held2) {
+		if (held2)
+			gfs2_glock_hold(gl);
+		else
+			gfs2_glock_put(gl);
+	}
+
+	gl->gl_state = new_state;
+	gl->gl_tchange = jiffies;
+}
+
+static void gfs2_demote_wake(struct gfs2_glock *gl)
+{
+	gl->gl_demote_state = LM_ST_EXCLUSIVE;
+	clear_bit(GLF_DEMOTE, &gl->gl_flags);
+	smp_mb__after_clear_bit();
+	wake_up_bit(&gl->gl_flags, GLF_DEMOTE);
+}
+
+/**
+ * finish_xmote - The DLM has replied to one of our lock requests
+ * @gl: The glock
+ * @ret: The status from the DLM
+ *
+ */
+
+static void finish_xmote(struct gfs2_glock *gl, unsigned int ret)
+{
+	const struct gfs2_glock_operations *glops = gl->gl_ops;
+	struct gfs2_holder *gh;
+	unsigned state = ret & LM_OUT_ST_MASK;
+
+	spin_lock(&gl->gl_spin);
+	state_change(gl, state);
+	gh = find_first_waiter(gl);
+
+	/* Demote to UN request arrived during demote to SH or DF */
+	if (test_bit(GLF_DEMOTE_IN_PROGRESS, &gl->gl_flags) &&
+	    state != LM_ST_UNLOCKED && gl->gl_demote_state == LM_ST_UNLOCKED)
+		gl->gl_target = LM_ST_UNLOCKED;
+
+	/* Check for state != intended state */
+	if (unlikely(state != gl->gl_target)) {
+		if (gh && !test_bit(GLF_DEMOTE_IN_PROGRESS, &gl->gl_flags)) {
+			/* move to back of queue and try next entry */
+			if (ret & LM_OUT_CANCELED) {
+				if ((gh->gh_flags & LM_FLAG_PRIORITY) == 0)
+					list_move_tail(&gh->gh_list, &gl->gl_holders);
+				gh = find_first_waiter(gl);
+				gl->gl_target = gh->gh_state;
+				goto retry;
+			}
+			/* Some error or failed "try lock" - report it */
+			if ((ret & LM_OUT_ERROR) ||
+			    (gh->gh_flags & (LM_FLAG_TRY | LM_FLAG_TRY_1CB))) {
+				gl->gl_target = gl->gl_state;
+				do_error(gl, ret);
+				goto out;
+			}
+		}
+		switch(state) {
+		/* Unlocked due to conversion deadlock, try again */
+		case LM_ST_UNLOCKED:
+retry:
+			do_xmote(gl, gh, gl->gl_target);
+			break;
+		/* Conversion fails, unlock and try again */
+		case LM_ST_SHARED:
+		case LM_ST_DEFERRED:
+			do_xmote(gl, gh, LM_ST_UNLOCKED);
+			break;
+		default: /* Everything else */
+			printk(KERN_ERR "GFS2: wanted %u got %u\n", gl->gl_target, state);
+			GLOCK_BUG_ON(gl, 1);
+		}
+		spin_unlock(&gl->gl_spin);
+		gfs2_glock_put(gl);
+		return;
+	}
+
+	/* Fast path - we got what we asked for */
+	if (test_and_clear_bit(GLF_DEMOTE_IN_PROGRESS, &gl->gl_flags))
+		gfs2_demote_wake(gl);
+	if (state != LM_ST_UNLOCKED) {
+		if (glops->go_xmote_bh) {
+			int rv;
+			spin_unlock(&gl->gl_spin);
+			rv = glops->go_xmote_bh(gl, gh);
+			if (rv == -EAGAIN)
+				return;
+			spin_lock(&gl->gl_spin);
+			if (rv) {
+				do_error(gl, rv);
+				goto out;
+			}
+		}
+		do_promote(gl);
+	}
+out:
+	clear_bit(GLF_LOCK, &gl->gl_flags);
+	spin_unlock(&gl->gl_spin);
+	gfs2_glock_put(gl);
+}
+
+static unsigned int gfs2_lm_lock(struct gfs2_sbd *sdp, void *lock,
+				 unsigned int cur_state, unsigned int req_state,
+				 unsigned int flags)
+{
+	int ret = LM_OUT_ERROR;
+
+	if (!sdp->sd_lockstruct.ls_ops->lm_lock)
+		return req_state == LM_ST_UNLOCKED ? 0 : req_state;
+
+	if (likely(!test_bit(SDF_SHUTDOWN, &sdp->sd_flags)))
+		ret = sdp->sd_lockstruct.ls_ops->lm_lock(lock, cur_state,
+							 req_state, flags);
+	return ret;
+}
+
+/**
+ * do_xmote - Calls the DLM to change the state of a lock
+ * @gl: The lock state
+ * @gh: The holder (only for promotes)
+ * @target: The target lock state
+ *
+ */
+
+static void do_xmote(struct gfs2_glock *gl, struct gfs2_holder *gh, unsigned int target)
+{
+	const struct gfs2_glock_operations *glops = gl->gl_ops;
+	struct gfs2_sbd *sdp = gl->gl_sbd;
+	unsigned int lck_flags = gh ? gh->gh_flags : 0;
+	int ret;
+
+	lck_flags &= (LM_FLAG_TRY | LM_FLAG_TRY_1CB | LM_FLAG_NOEXP |
+		      LM_FLAG_PRIORITY);
+	BUG_ON(gl->gl_state == target);
+	BUG_ON(gl->gl_state == gl->gl_target);
+	if ((target == LM_ST_UNLOCKED || target == LM_ST_DEFERRED) &&
+	    glops->go_inval) {
+		set_bit(GLF_INVALIDATE_IN_PROGRESS, &gl->gl_flags);
+		do_error(gl, 0); /* Fail queued try locks */
+	}
+	spin_unlock(&gl->gl_spin);
+	if (glops->go_xmote_th)
+		glops->go_xmote_th(gl);
+	if (test_bit(GLF_INVALIDATE_IN_PROGRESS, &gl->gl_flags))
+		glops->go_inval(gl, target == LM_ST_DEFERRED ? 0 : DIO_METADATA);
+	clear_bit(GLF_INVALIDATE_IN_PROGRESS, &gl->gl_flags);
+
+	gfs2_glock_hold(gl);
+	if (target != LM_ST_UNLOCKED && (gl->gl_state == LM_ST_SHARED ||
+	    gl->gl_state == LM_ST_DEFERRED) &&
+	    !(lck_flags & (LM_FLAG_TRY | LM_FLAG_TRY_1CB)))
+		lck_flags |= LM_FLAG_TRY_1CB;
+	ret = gfs2_lm_lock(sdp, gl->gl_lock, gl->gl_state, target, lck_flags);
+
+	if (!(ret & LM_OUT_ASYNC)) {
+		finish_xmote(gl, ret);
+		gfs2_glock_hold(gl);
+		if (queue_delayed_work(glock_workqueue, &gl->gl_work, 0) == 0)
+			gfs2_glock_put(gl);
+	} else {
+		GLOCK_BUG_ON(gl, ret != LM_OUT_ASYNC);
+	}
+	spin_lock(&gl->gl_spin);
+}
+
+/**
+ * find_first_holder - find the first "holder" gh
+ * @gl: the glock
+ */
+
+static inline struct gfs2_holder *find_first_holder(const struct gfs2_glock *gl)
+{
+	struct gfs2_holder *gh;
+
+	if (!list_empty(&gl->gl_holders)) {
+		gh = list_entry(gl->gl_holders.next, struct gfs2_holder, gh_list);
+		if (test_bit(HIF_HOLDER, &gh->gh_iflags))
+			return gh;
+	}
+	return NULL;
+}
+
+/**
+ * run_queue - do all outstanding tasks related to a glock
+ * @gl: The glock in question
+ * @nonblock: True if we must not block in run_queue
+ *
+ */
+
+static void run_queue(struct gfs2_glock *gl, const int nonblock)
+{
+	struct gfs2_holder *gh = NULL;
+
+	if (test_and_set_bit(GLF_LOCK, &gl->gl_flags))
+		return;
+
+	GLOCK_BUG_ON(gl, test_bit(GLF_DEMOTE_IN_PROGRESS, &gl->gl_flags));
+
+	if (test_bit(GLF_DEMOTE, &gl->gl_flags) &&
+	    gl->gl_demote_state != gl->gl_state) {
+		if (find_first_holder(gl))
+			goto out;
+		if (nonblock)
+			goto out_sched;
+		set_bit(GLF_DEMOTE_IN_PROGRESS, &gl->gl_flags);
+		GLOCK_BUG_ON(gl, gl->gl_demote_state == LM_ST_EXCLUSIVE);
+		gl->gl_target = gl->gl_demote_state;
+	} else {
+		if (test_bit(GLF_DEMOTE, &gl->gl_flags))
+			gfs2_demote_wake(gl);
+		if (do_promote(gl) == 0)
+			goto out;
+		gh = find_first_waiter(gl);
+		gl->gl_target = gh->gh_state;
+		if (!(gh->gh_flags & (LM_FLAG_TRY | LM_FLAG_TRY_1CB)))
+			do_error(gl, 0); /* Fail queued try locks */
+	}
+	do_xmote(gl, gh, gl->gl_target);
+	return;
+
+out_sched:
+	gfs2_glock_hold(gl);
+	if (queue_delayed_work(glock_workqueue, &gl->gl_work, 0) == 0)
+		gfs2_glock_put(gl);
+out:
+	clear_bit(GLF_LOCK, &gl->gl_flags);
+}
+
 static void glock_work_func(struct work_struct *work)
 {
+	unsigned long delay = 0;
 	struct gfs2_glock *gl = container_of(work, struct gfs2_glock, gl_work.work);
 
+	if (test_and_clear_bit(GLF_REPLY_PENDING, &gl->gl_flags))
+		finish_xmote(gl, gl->gl_reply);
 	spin_lock(&gl->gl_spin);
-	if (test_and_clear_bit(GLF_PENDING_DEMOTE, &gl->gl_flags))
-		set_bit(GLF_DEMOTE, &gl->gl_flags);
-	run_queue(gl);
+	if (test_and_clear_bit(GLF_PENDING_DEMOTE, &gl->gl_flags) &&
+	    gl->gl_state != LM_ST_UNLOCKED &&
+	    gl->gl_demote_state != LM_ST_EXCLUSIVE) {
+		unsigned long holdtime, now = jiffies;
+		holdtime = gl->gl_tchange + gl->gl_ops->go_min_hold_time;
+		if (time_before(now, holdtime))
+			delay = holdtime - now;
+		set_bit(delay ? GLF_PENDING_DEMOTE : GLF_DEMOTE, &gl->gl_flags);
+	}
+	run_queue(gl, 0);
 	spin_unlock(&gl->gl_spin);
-	gfs2_glock_put(gl);
+	if (!delay ||
+	    queue_delayed_work(glock_workqueue, &gl->gl_work, delay) == 0)
+		gfs2_glock_put(gl);
 }
 
 static int gfs2_lm_get_lock(struct gfs2_sbd *sdp, struct lm_lockname *name,
 		     void **lockp)
 {
 	int error = -EIO;
+	if (!sdp->sd_lockstruct.ls_ops->lm_get_lock)
+		return 0;
 	if (likely(!test_bit(SDF_SHUTDOWN, &sdp->sd_flags)))
 		error = sdp->sd_lockstruct.ls_ops->lm_get_lock(
 				sdp->sd_lockstruct.ls_lockspace, name, lockp);
@@ -342,12 +689,10 @@ int gfs2_glock_get(struct gfs2_sbd *sdp, u64 number,
 	gl->gl_name = name;
 	atomic_set(&gl->gl_ref, 1);
 	gl->gl_state = LM_ST_UNLOCKED;
+	gl->gl_target = LM_ST_UNLOCKED;
 	gl->gl_demote_state = LM_ST_EXCLUSIVE;
 	gl->gl_hash = hash;
-	gl->gl_owner_pid = NULL;
-	gl->gl_ip = 0;
 	gl->gl_ops = glops;
-	gl->gl_req_gh = NULL;
 	gl->gl_stamp = jiffies;
 	gl->gl_tchange = jiffies;
 	gl->gl_object = NULL;
@@ -447,13 +792,6 @@ void gfs2_holder_uninit(struct gfs2_holder *gh)
 	gh->gh_ip = 0;
 }
 
-static void gfs2_holder_wake(struct gfs2_holder *gh)
-{
-	clear_bit(HIF_WAIT, &gh->gh_iflags);
-	smp_mb__after_clear_bit();
-	wake_up_bit(&gh->gh_iflags, HIF_WAIT);
-}
-
 static int just_schedule(void *word)
 {
         schedule();
@@ -466,14 +804,6 @@ static void wait_on_holder(struct gfs2_holder *gh)
 	wait_on_bit(&gh->gh_iflags, HIF_WAIT, just_schedule, TASK_UNINTERRUPTIBLE);
 }
 
-static void gfs2_demote_wake(struct gfs2_glock *gl)
-{
-	gl->gl_demote_state = LM_ST_EXCLUSIVE;
-        clear_bit(GLF_DEMOTE, &gl->gl_flags);
-        smp_mb__after_clear_bit();
-        wake_up_bit(&gl->gl_flags, GLF_DEMOTE);
-}
-
 static void wait_on_demote(struct gfs2_glock *gl)
 {
 	might_sleep();
@@ -481,217 +811,6 @@ static void wait_on_demote(struct gfs2_glock *gl)
 }
 
 /**
- * rq_mutex - process a mutex request in the queue
- * @gh: the glock holder
- *
- * Returns: 1 if the queue is blocked
- */
-
-static int rq_mutex(struct gfs2_holder *gh)
-{
-	struct gfs2_glock *gl = gh->gh_gl;
-
-	list_del_init(&gh->gh_list);
-	/*  gh->gh_error never examined.  */
-	set_bit(GLF_LOCK, &gl->gl_flags);
-	clear_bit(HIF_WAIT, &gh->gh_iflags);
-	smp_mb();
-	wake_up_bit(&gh->gh_iflags, HIF_WAIT);
-
-	return 1;
-}
-
-/**
- * rq_promote - process a promote request in the queue
- * @gh: the glock holder
- *
- * Acquire a new inter-node lock, or change a lock state to more restrictive.
- *
- * Returns: 1 if the queue is blocked
- */
-
-static int rq_promote(struct gfs2_holder *gh)
-{
-	struct gfs2_glock *gl = gh->gh_gl;
-
-	if (!relaxed_state_ok(gl->gl_state, gh->gh_state, gh->gh_flags)) {
-		if (list_empty(&gl->gl_holders)) {
-			gl->gl_req_gh = gh;
-			set_bit(GLF_LOCK, &gl->gl_flags);
-			spin_unlock(&gl->gl_spin);
-			gfs2_glock_xmote_th(gh->gh_gl, gh);
-			spin_lock(&gl->gl_spin);
-		}
-		return 1;
-	}
-
-	if (list_empty(&gl->gl_holders)) {
-		set_bit(HIF_FIRST, &gh->gh_iflags);
-		set_bit(GLF_LOCK, &gl->gl_flags);
-	} else {
-		struct gfs2_holder *next_gh;
-		if (gh->gh_state == LM_ST_EXCLUSIVE)
-			return 1;
-		next_gh = list_entry(gl->gl_holders.next, struct gfs2_holder,
-				     gh_list);
-		if (next_gh->gh_state == LM_ST_EXCLUSIVE)
-			 return 1;
-	}
-
-	list_move_tail(&gh->gh_list, &gl->gl_holders);
-	gh->gh_error = 0;
-	set_bit(HIF_HOLDER, &gh->gh_iflags);
-
-	gfs2_holder_wake(gh);
-
-	return 0;
-}
-
-/**
- * rq_demote - process a demote request in the queue
- * @gh: the glock holder
- *
- * Returns: 1 if the queue is blocked
- */
-
-static int rq_demote(struct gfs2_glock *gl)
-{
-	if (!list_empty(&gl->gl_holders))
-		return 1;
-
-	if (gl->gl_state == gl->gl_demote_state ||
-	    gl->gl_state == LM_ST_UNLOCKED) {
-		gfs2_demote_wake(gl);
-		return 0;
-	}
-
-	set_bit(GLF_LOCK, &gl->gl_flags);
-	set_bit(GLF_DEMOTE_IN_PROGRESS, &gl->gl_flags);
-
-	if (gl->gl_demote_state == LM_ST_UNLOCKED ||
-	    gl->gl_state != LM_ST_EXCLUSIVE) {
-		spin_unlock(&gl->gl_spin);
-		gfs2_glock_drop_th(gl);
-	} else {
-		spin_unlock(&gl->gl_spin);
-		gfs2_glock_xmote_th(gl, NULL);
-	}
-
-	spin_lock(&gl->gl_spin);
-	clear_bit(GLF_DEMOTE_IN_PROGRESS, &gl->gl_flags);
-
-	return 0;
-}
-
-/**
- * run_queue - process holder structures on a glock
- * @gl: the glock
- *
- */
-static void run_queue(struct gfs2_glock *gl)
-{
-	struct gfs2_holder *gh;
-	int blocked = 1;
-
-	for (;;) {
-		if (test_bit(GLF_LOCK, &gl->gl_flags))
-			break;
-
-		if (!list_empty(&gl->gl_waiters1)) {
-			gh = list_entry(gl->gl_waiters1.next,
-					struct gfs2_holder, gh_list);
-			blocked = rq_mutex(gh);
-		} else if (test_bit(GLF_DEMOTE, &gl->gl_flags)) {
-			blocked = rq_demote(gl);
-			if (test_bit(GLF_WAITERS2, &gl->gl_flags) &&
-				     !blocked) {
-				set_bit(GLF_DEMOTE, &gl->gl_flags);
-				gl->gl_demote_state = LM_ST_UNLOCKED;
-			}
-			clear_bit(GLF_WAITERS2, &gl->gl_flags);
-		} else if (!list_empty(&gl->gl_waiters3)) {
-			gh = list_entry(gl->gl_waiters3.next,
-					struct gfs2_holder, gh_list);
-			blocked = rq_promote(gh);
-		} else
-			break;
-
-		if (blocked)
-			break;
-	}
-}
-
-/**
- * gfs2_glmutex_lock - acquire a local lock on a glock
- * @gl: the glock
- *
- * Gives caller exclusive access to manipulate a glock structure.
- */
-
-static void gfs2_glmutex_lock(struct gfs2_glock *gl)
-{
-	spin_lock(&gl->gl_spin);
-	if (test_and_set_bit(GLF_LOCK, &gl->gl_flags)) {
-		struct gfs2_holder gh;
-
-		gfs2_holder_init(gl, 0, 0, &gh);
-		set_bit(HIF_WAIT, &gh.gh_iflags);
-		list_add_tail(&gh.gh_list, &gl->gl_waiters1);
-		spin_unlock(&gl->gl_spin);
-		wait_on_holder(&gh);
-		gfs2_holder_uninit(&gh);
-	} else {
-		gl->gl_owner_pid = get_pid(task_pid(current));
-		gl->gl_ip = (unsigned long)__builtin_return_address(0);
-		spin_unlock(&gl->gl_spin);
-	}
-}
-
-/**
- * gfs2_glmutex_trylock - try to acquire a local lock on a glock
- * @gl: the glock
- *
- * Returns: 1 if the glock is acquired
- */
-
-static int gfs2_glmutex_trylock(struct gfs2_glock *gl)
-{
-	int acquired = 1;
-
-	spin_lock(&gl->gl_spin);
-	if (test_and_set_bit(GLF_LOCK, &gl->gl_flags)) {
-		acquired = 0;
-	} else {
-		gl->gl_owner_pid = get_pid(task_pid(current));
-		gl->gl_ip = (unsigned long)__builtin_return_address(0);
-	}
-	spin_unlock(&gl->gl_spin);
-
-	return acquired;
-}
-
-/**
- * gfs2_glmutex_unlock - release a local lock on a glock
- * @gl: the glock
- *
- */
-
-static void gfs2_glmutex_unlock(struct gfs2_glock *gl)
-{
-	struct pid *pid;
-
-	spin_lock(&gl->gl_spin);
-	clear_bit(GLF_LOCK, &gl->gl_flags);
-	pid = gl->gl_owner_pid;
-	gl->gl_owner_pid = NULL;
-	gl->gl_ip = 0;
-	run_queue(gl);
-	spin_unlock(&gl->gl_spin);
-
-	put_pid(pid);
-}
-
-/**
  * handle_callback - process a demote request
  * @gl: the glock
  * @state: the state the caller wants us to change to
@@ -705,398 +824,45 @@ static void handle_callback(struct gfs2_glock *gl, unsigned int state,
 {
 	int bit = delay ? GLF_PENDING_DEMOTE : GLF_DEMOTE;
 
-	spin_lock(&gl->gl_spin);
 	set_bit(bit, &gl->gl_flags);
 	if (gl->gl_demote_state == LM_ST_EXCLUSIVE) {
 		gl->gl_demote_state = state;
 		gl->gl_demote_time = jiffies;
 		if (remote && gl->gl_ops->go_type == LM_TYPE_IOPEN &&
-		    gl->gl_object) {
+		    gl->gl_object)
 			gfs2_glock_schedule_for_reclaim(gl);
-			spin_unlock(&gl->gl_spin);
-			return;
-		}
 	} else if (gl->gl_demote_state != LM_ST_UNLOCKED &&
 			gl->gl_demote_state != state) {
-		if (test_bit(GLF_DEMOTE_IN_PROGRESS,  &gl->gl_flags)) 
-			set_bit(GLF_WAITERS2, &gl->gl_flags);
-		else 
-			gl->gl_demote_state = LM_ST_UNLOCKED;
-	}
-	spin_unlock(&gl->gl_spin);
-}
-
-/**
- * state_change - record that the glock is now in a different state
- * @gl: the glock
- * @new_state the new state
- *
- */
-
-static void state_change(struct gfs2_glock *gl, unsigned int new_state)
-{
-	int held1, held2;
-
-	held1 = (gl->gl_state != LM_ST_UNLOCKED);
-	held2 = (new_state != LM_ST_UNLOCKED);
-
-	if (held1 != held2) {
-		if (held2)
-			gfs2_glock_hold(gl);
-		else
-			gfs2_glock_put(gl);
+		gl->gl_demote_state = LM_ST_UNLOCKED;
 	}
-
-	gl->gl_state = new_state;
-	gl->gl_tchange = jiffies;
 }
 
 /**
- * drop_bh - Called after a lock module unlock completes
- * @gl: the glock
- * @ret: the return status
- *
- * Doesn't wake up the process waiting on the struct gfs2_holder (if any)
- * Doesn't drop the reference on the glock the top half took out
- *
- */
-
-static void drop_bh(struct gfs2_glock *gl, unsigned int ret)
-{
-	struct gfs2_sbd *sdp = gl->gl_sbd;
-	struct gfs2_holder *gh = gl->gl_req_gh;
-
-	gfs2_assert_warn(sdp, test_bit(GLF_LOCK, &gl->gl_flags));
-	gfs2_assert_warn(sdp, list_empty(&gl->gl_holders));
-	gfs2_assert_warn(sdp, !ret);
-
-	state_change(gl, LM_ST_UNLOCKED);
-
-	if (test_and_clear_bit(GLF_CONV_DEADLK, &gl->gl_flags)) {
-		spin_lock(&gl->gl_spin);
-		gh->gh_error = 0;
-		spin_unlock(&gl->gl_spin);
-		gfs2_glock_xmote_th(gl, gl->gl_req_gh);
-		gfs2_glock_put(gl);
-		return;
-	}
-
-	spin_lock(&gl->gl_spin);
-	gfs2_demote_wake(gl);
-	clear_bit(GLF_LOCK, &gl->gl_flags);
-	spin_unlock(&gl->gl_spin);
-	gfs2_glock_put(gl);
-}
-
-/**
- * xmote_bh - Called after the lock module is done acquiring a lock
- * @gl: The glock in question
- * @ret: the int returned from the lock module
- *
- */
-
-static void xmote_bh(struct gfs2_glock *gl, unsigned int ret)
-{
-	struct gfs2_sbd *sdp = gl->gl_sbd;
-	const struct gfs2_glock_operations *glops = gl->gl_ops;
-	struct gfs2_holder *gh = gl->gl_req_gh;
-	int op_done = 1;
-
-	if (!gh && (ret & LM_OUT_ST_MASK) == LM_ST_UNLOCKED) {
-		drop_bh(gl, ret);
-		return;
-	}
-
-	gfs2_assert_warn(sdp, test_bit(GLF_LOCK, &gl->gl_flags));
-	gfs2_assert_warn(sdp, list_empty(&gl->gl_holders));
-	gfs2_assert_warn(sdp, !(ret & LM_OUT_ASYNC));
-
-	state_change(gl, ret & LM_OUT_ST_MASK);
-
-	/*  Deal with each possible exit condition  */
-
-	if (!gh) {
-		gl->gl_stamp = jiffies;
-		if (ret & LM_OUT_CANCELED) {
-			op_done = 0;
-		} else {
-			spin_lock(&gl->gl_spin);
-			if (gl->gl_state != gl->gl_demote_state) {
-				spin_unlock(&gl->gl_spin);
-				gfs2_glock_drop_th(gl);
-				gfs2_glock_put(gl);
-				return;
-			}
-			gfs2_demote_wake(gl);
-			spin_unlock(&gl->gl_spin);
-		}
-	} else {
-		spin_lock(&gl->gl_spin);
-		if (ret & LM_OUT_CONV_DEADLK) {
-			gh->gh_error = 0;
-			set_bit(GLF_CONV_DEADLK, &gl->gl_flags);
-			spin_unlock(&gl->gl_spin);
-			gfs2_glock_drop_th(gl);
-			gfs2_glock_put(gl);
-			return;
-		}
-		list_del_init(&gh->gh_list);
-		gh->gh_error = -EIO;
-		if (unlikely(test_bit(SDF_SHUTDOWN, &sdp->sd_flags))) 
-			goto out;
-		gh->gh_error = GLR_CANCELED;
-		if (ret & LM_OUT_CANCELED) 
-			goto out;
-		if (relaxed_state_ok(gl->gl_state, gh->gh_state, gh->gh_flags)) {
-			list_add_tail(&gh->gh_list, &gl->gl_holders);
-			gh->gh_error = 0;
-			set_bit(HIF_HOLDER, &gh->gh_iflags);
-			set_bit(HIF_FIRST, &gh->gh_iflags);
-			op_done = 0;
-			goto out;
-		}
-		gh->gh_error = GLR_TRYFAILED;
-		if (gh->gh_flags & (LM_FLAG_TRY | LM_FLAG_TRY_1CB))
-			goto out;
-		gh->gh_error = -EINVAL;
-		if (gfs2_assert_withdraw(sdp, 0) == -1)
-			fs_err(sdp, "ret = 0x%.8X\n", ret);
-out:
-		spin_unlock(&gl->gl_spin);
-	}
-
-	if (glops->go_xmote_bh)
-		glops->go_xmote_bh(gl);
-
-	if (op_done) {
-		spin_lock(&gl->gl_spin);
-		gl->gl_req_gh = NULL;
-		clear_bit(GLF_LOCK, &gl->gl_flags);
-		spin_unlock(&gl->gl_spin);
-	}
-
-	gfs2_glock_put(gl);
-
-	if (gh)
-		gfs2_holder_wake(gh);
-}
-
-static unsigned int gfs2_lm_lock(struct gfs2_sbd *sdp, void *lock,
-				 unsigned int cur_state, unsigned int req_state,
-				 unsigned int flags)
-{
-	int ret = 0;
-	if (likely(!test_bit(SDF_SHUTDOWN, &sdp->sd_flags)))
-		ret = sdp->sd_lockstruct.ls_ops->lm_lock(lock, cur_state,
-							 req_state, flags);
-	return ret;
-}
-
-/**
- * gfs2_glock_xmote_th - Call into the lock module to acquire or change a glock
- * @gl: The glock in question
- * @state: the requested state
- * @flags: modifier flags to the lock call
- *
- */
-
-static void gfs2_glock_xmote_th(struct gfs2_glock *gl, struct gfs2_holder *gh)
-{
-	struct gfs2_sbd *sdp = gl->gl_sbd;
-	int flags = gh ? gh->gh_flags : 0;
-	unsigned state = gh ? gh->gh_state : gl->gl_demote_state;
-	const struct gfs2_glock_operations *glops = gl->gl_ops;
-	int lck_flags = flags & (LM_FLAG_TRY | LM_FLAG_TRY_1CB |
-				 LM_FLAG_NOEXP | LM_FLAG_ANY |
-				 LM_FLAG_PRIORITY);
-	unsigned int lck_ret;
-
-	if (glops->go_xmote_th)
-		glops->go_xmote_th(gl);
-	if (state == LM_ST_DEFERRED && glops->go_inval)
-		glops->go_inval(gl, DIO_METADATA);
-
-	gfs2_assert_warn(sdp, test_bit(GLF_LOCK, &gl->gl_flags));
-	gfs2_assert_warn(sdp, list_empty(&gl->gl_holders));
-	gfs2_assert_warn(sdp, state != LM_ST_UNLOCKED);
-	gfs2_assert_warn(sdp, state != gl->gl_state);
-
-	gfs2_glock_hold(gl);
-
-	lck_ret = gfs2_lm_lock(sdp, gl->gl_lock, gl->gl_state, state, lck_flags);
-
-	if (gfs2_assert_withdraw(sdp, !(lck_ret & LM_OUT_ERROR)))
-		return;
-
-	if (lck_ret & LM_OUT_ASYNC)
-		gfs2_assert_warn(sdp, lck_ret == LM_OUT_ASYNC);
-	else
-		xmote_bh(gl, lck_ret);
-}
-
-static unsigned int gfs2_lm_unlock(struct gfs2_sbd *sdp, void *lock,
-				   unsigned int cur_state)
-{
-	int ret = 0;
-	if (likely(!test_bit(SDF_SHUTDOWN, &sdp->sd_flags)))
-		ret =  sdp->sd_lockstruct.ls_ops->lm_unlock(lock, cur_state);
-	return ret;
-}
-
-/**
- * gfs2_glock_drop_th - call into the lock module to unlock a lock
- * @gl: the glock
- *
- */
-
-static void gfs2_glock_drop_th(struct gfs2_glock *gl)
-{
-	struct gfs2_sbd *sdp = gl->gl_sbd;
-	const struct gfs2_glock_operations *glops = gl->gl_ops;
-	unsigned int ret;
-
-	if (glops->go_xmote_th)
-		glops->go_xmote_th(gl);
-	if (glops->go_inval)
-		glops->go_inval(gl, DIO_METADATA);
-
-	gfs2_assert_warn(sdp, test_bit(GLF_LOCK, &gl->gl_flags));
-	gfs2_assert_warn(sdp, list_empty(&gl->gl_holders));
-	gfs2_assert_warn(sdp, gl->gl_state != LM_ST_UNLOCKED);
-
-	gfs2_glock_hold(gl);
-
-	ret = gfs2_lm_unlock(sdp, gl->gl_lock, gl->gl_state);
-
-	if (gfs2_assert_withdraw(sdp, !(ret & LM_OUT_ERROR)))
-		return;
-
-	if (!ret)
-		drop_bh(gl, ret);
-	else
-		gfs2_assert_warn(sdp, ret == LM_OUT_ASYNC);
-}
-
-/**
- * do_cancels - cancel requests for locks stuck waiting on an expire flag
- * @gh: the LM_FLAG_PRIORITY holder waiting to acquire the lock
- *
- * Don't cancel GL_NOCANCEL requests.
- */
-
-static void do_cancels(struct gfs2_holder *gh)
-{
-	struct gfs2_glock *gl = gh->gh_gl;
-	struct gfs2_sbd *sdp = gl->gl_sbd;
-
-	spin_lock(&gl->gl_spin);
-
-	while (gl->gl_req_gh != gh &&
-	       !test_bit(HIF_HOLDER, &gh->gh_iflags) &&
-	       !list_empty(&gh->gh_list)) {
-		if (!(gl->gl_req_gh && (gl->gl_req_gh->gh_flags & GL_NOCANCEL))) {
-			spin_unlock(&gl->gl_spin);
-			if (likely(!test_bit(SDF_SHUTDOWN, &sdp->sd_flags)))
-				sdp->sd_lockstruct.ls_ops->lm_cancel(gl->gl_lock);
-			msleep(100);
-			spin_lock(&gl->gl_spin);
-		} else {
-			spin_unlock(&gl->gl_spin);
-			msleep(100);
-			spin_lock(&gl->gl_spin);
-		}
-	}
-
-	spin_unlock(&gl->gl_spin);
-}
-
-/**
- * glock_wait_internal - wait on a glock acquisition
+ * gfs2_glock_wait - wait on a glock acquisition
  * @gh: the glock holder
  *
  * Returns: 0 on success
  */
 
-static int glock_wait_internal(struct gfs2_holder *gh)
+int gfs2_glock_wait(struct gfs2_holder *gh)
 {
-	struct gfs2_glock *gl = gh->gh_gl;
-	struct gfs2_sbd *sdp = gl->gl_sbd;
-	const struct gfs2_glock_operations *glops = gl->gl_ops;
-
-	if (test_bit(HIF_ABORTED, &gh->gh_iflags))
-		return -EIO;
-
-	if (gh->gh_flags & (LM_FLAG_TRY | LM_FLAG_TRY_1CB)) {
-		spin_lock(&gl->gl_spin);
-		if (gl->gl_req_gh != gh &&
-		    !test_bit(HIF_HOLDER, &gh->gh_iflags) &&
-		    !list_empty(&gh->gh_list)) {
-			list_del_init(&gh->gh_list);
-			gh->gh_error = GLR_TRYFAILED;
-			run_queue(gl);
-			spin_unlock(&gl->gl_spin);
-			return gh->gh_error;
-		}
-		spin_unlock(&gl->gl_spin);
-	}
-
-	if (gh->gh_flags & LM_FLAG_PRIORITY)
-		do_cancels(gh);
-
 	wait_on_holder(gh);
-	if (gh->gh_error)
-		return gh->gh_error;
-
-	gfs2_assert_withdraw(sdp, test_bit(HIF_HOLDER, &gh->gh_iflags));
-	gfs2_assert_withdraw(sdp, relaxed_state_ok(gl->gl_state, gh->gh_state,
-						   gh->gh_flags));
-
-	if (test_bit(HIF_FIRST, &gh->gh_iflags)) {
-		gfs2_assert_warn(sdp, test_bit(GLF_LOCK, &gl->gl_flags));
-
-		if (glops->go_lock) {
-			gh->gh_error = glops->go_lock(gh);
-			if (gh->gh_error) {
-				spin_lock(&gl->gl_spin);
-				list_del_init(&gh->gh_list);
-				spin_unlock(&gl->gl_spin);
-			}
-		}
-
-		spin_lock(&gl->gl_spin);
-		gl->gl_req_gh = NULL;
-		clear_bit(GLF_LOCK, &gl->gl_flags);
-		run_queue(gl);
-		spin_unlock(&gl->gl_spin);
-	}
-
 	return gh->gh_error;
 }
 
-static inline struct gfs2_holder *
-find_holder_by_owner(struct list_head *head, struct pid *pid)
-{
-	struct gfs2_holder *gh;
-
-	list_for_each_entry(gh, head, gh_list) {
-		if (gh->gh_owner_pid == pid)
-			return gh;
-	}
-
-	return NULL;
-}
-
-static void print_dbg(struct glock_iter *gi, const char *fmt, ...)
+void gfs2_print_dbg(struct seq_file *seq, const char *fmt, ...)
 {
 	va_list args;
 
 	va_start(args, fmt);
-	if (gi) {
+	if (seq) {
+		struct gfs2_glock_iter *gi = seq->private;
 		vsprintf(gi->string, fmt, args);
-		seq_printf(gi->seq, gi->string);
-	}
-	else
+		seq_printf(seq, gi->string);
+	} else {
+		printk(KERN_ERR " ");
 		vprintk(fmt, args);
+	}
 	va_end(args);
 }
 
@@ -1104,50 +870,76 @@ static void print_dbg(struct glock_iter *gi, const char *fmt, ...)
  * add_to_queue - Add a holder to the wait queue (but look for recursion)
  * @gh: the holder structure to add
  *
+ * Eventually we should move the recursive locking trap to a
+ * debugging option or something like that. This is the fast
+ * path and needs to have the minimum number of distractions.
+ * 
  */
 
-static void add_to_queue(struct gfs2_holder *gh)
+static inline void add_to_queue(struct gfs2_holder *gh)
 {
 	struct gfs2_glock *gl = gh->gh_gl;
-	struct gfs2_holder *existing;
+	struct gfs2_sbd *sdp = gl->gl_sbd;
+	struct list_head *insert_pt = NULL;
+	struct gfs2_holder *gh2;
+	int try_lock = 0;
 
 	BUG_ON(gh->gh_owner_pid == NULL);
 	if (test_and_set_bit(HIF_WAIT, &gh->gh_iflags))
 		BUG();
 
-	if (!(gh->gh_flags & GL_FLOCK)) {
-		existing = find_holder_by_owner(&gl->gl_holders, 
-						gh->gh_owner_pid);
-		if (existing) {
-			print_symbol(KERN_WARNING "original: %s\n", 
-				     existing->gh_ip);
-			printk(KERN_INFO "pid : %d\n",
-					pid_nr(existing->gh_owner_pid));
-			printk(KERN_INFO "lock type : %d lock state : %d\n",
-			       existing->gh_gl->gl_name.ln_type, 
-			       existing->gh_gl->gl_state);
-			print_symbol(KERN_WARNING "new: %s\n", gh->gh_ip);
-			printk(KERN_INFO "pid : %d\n",
-					pid_nr(gh->gh_owner_pid));
-			printk(KERN_INFO "lock type : %d lock state : %d\n",
-			       gl->gl_name.ln_type, gl->gl_state);
-			BUG();
-		}
-		
-		existing = find_holder_by_owner(&gl->gl_waiters3, 
-						gh->gh_owner_pid);
-		if (existing) {
-			print_symbol(KERN_WARNING "original: %s\n", 
-				     existing->gh_ip);
-			print_symbol(KERN_WARNING "new: %s\n", gh->gh_ip);
-			BUG();
+	if (gh->gh_flags & (LM_FLAG_TRY | LM_FLAG_TRY_1CB)) {
+		if (test_bit(GLF_LOCK, &gl->gl_flags))
+			try_lock = 1;
+		if (test_bit(GLF_INVALIDATE_IN_PROGRESS, &gl->gl_flags))
+			goto fail;
+	}
+
+	list_for_each_entry(gh2, &gl->gl_holders, gh_list) {
+		if (unlikely(gh2->gh_owner_pid == gh->gh_owner_pid &&
+		    (gh->gh_gl->gl_ops->go_type != LM_TYPE_FLOCK)))
+			goto trap_recursive;
+		if (try_lock &&
+		    !(gh2->gh_flags & (LM_FLAG_TRY | LM_FLAG_TRY_1CB)) &&
+		    !may_grant(gl, gh)) {
+fail:
+			gh->gh_error = GLR_TRYFAILED;
+			gfs2_holder_wake(gh);
+			return;
 		}
+		if (test_bit(HIF_HOLDER, &gh2->gh_iflags))
+			continue;
+		if (unlikely((gh->gh_flags & LM_FLAG_PRIORITY) && !insert_pt))
+			insert_pt = &gh2->gh_list;
+	}
+	if (likely(insert_pt == NULL)) {
+		list_add_tail(&gh->gh_list, &gl->gl_holders);
+		if (unlikely(gh->gh_flags & LM_FLAG_PRIORITY))
+			goto do_cancel;
+		return;
+	}
+	list_add_tail(&gh->gh_list, insert_pt);
+do_cancel:
+	gh = list_entry(gl->gl_holders.next, struct gfs2_holder, gh_list);
+	if (!(gh->gh_flags & LM_FLAG_PRIORITY)) {
+		spin_unlock(&gl->gl_spin);
+		if (sdp->sd_lockstruct.ls_ops->lm_cancel)
+			sdp->sd_lockstruct.ls_ops->lm_cancel(gl->gl_lock);
+		spin_lock(&gl->gl_spin);
 	}
+	return;
 
-	if (gh->gh_flags & LM_FLAG_PRIORITY)
-		list_add(&gh->gh_list, &gl->gl_waiters3);
-	else
-		list_add_tail(&gh->gh_list, &gl->gl_waiters3);
+trap_recursive:
+	print_symbol(KERN_ERR "original: %s\n", gh2->gh_ip);
+	printk(KERN_ERR "pid: %d\n", pid_nr(gh2->gh_owner_pid));
+	printk(KERN_ERR "lock type: %d req lock state : %d\n",
+	       gh2->gh_gl->gl_name.ln_type, gh2->gh_state);
+	print_symbol(KERN_ERR "new: %s\n", gh->gh_ip);
+	printk(KERN_ERR "pid: %d\n", pid_nr(gh->gh_owner_pid));
+	printk(KERN_ERR "lock type: %d req lock state : %d\n",
+	       gh->gh_gl->gl_name.ln_type, gh->gh_state);
+	__dump_glock(NULL, gl);
+	BUG();
 }
 
 /**
@@ -1165,24 +957,16 @@ int gfs2_glock_nq(struct gfs2_holder *gh)
 	struct gfs2_sbd *sdp = gl->gl_sbd;
 	int error = 0;
 
-restart:
-	if (unlikely(test_bit(SDF_SHUTDOWN, &sdp->sd_flags))) {
-		set_bit(HIF_ABORTED, &gh->gh_iflags);
+	if (unlikely(test_bit(SDF_SHUTDOWN, &sdp->sd_flags)))
 		return -EIO;
-	}
 
 	spin_lock(&gl->gl_spin);
 	add_to_queue(gh);
-	run_queue(gl);
+	run_queue(gl, 1);
 	spin_unlock(&gl->gl_spin);
 
-	if (!(gh->gh_flags & GL_ASYNC)) {
-		error = glock_wait_internal(gh);
-		if (error == GLR_CANCELED) {
-			msleep(100);
-			goto restart;
-		}
-	}
+	if (!(gh->gh_flags & GL_ASYNC))
+		error = gfs2_glock_wait(gh);
 
 	return error;
 }
@@ -1196,48 +980,7 @@ restart:
 
 int gfs2_glock_poll(struct gfs2_holder *gh)
 {
-	struct gfs2_glock *gl = gh->gh_gl;
-	int ready = 0;
-
-	spin_lock(&gl->gl_spin);
-
-	if (test_bit(HIF_HOLDER, &gh->gh_iflags))
-		ready = 1;
-	else if (list_empty(&gh->gh_list)) {
-		if (gh->gh_error == GLR_CANCELED) {
-			spin_unlock(&gl->gl_spin);
-			msleep(100);
-			if (gfs2_glock_nq(gh))
-				return 1;
-			return 0;
-		} else
-			ready = 1;
-	}
-
-	spin_unlock(&gl->gl_spin);
-
-	return ready;
-}
-
-/**
- * gfs2_glock_wait - wait for a lock acquisition that ended in a GLR_ASYNC
- * @gh: the holder structure
- *
- * Returns: 0, GLR_TRYFAILED, or errno on failure
- */
-
-int gfs2_glock_wait(struct gfs2_holder *gh)
-{
-	int error;
-
-	error = glock_wait_internal(gh);
-	if (error == GLR_CANCELED) {
-		msleep(100);
-		gh->gh_flags &= ~GL_ASYNC;
-		error = gfs2_glock_nq(gh);
-	}
-
-	return error;
+	return test_bit(HIF_WAIT, &gh->gh_iflags) ? 0 : 1;
 }
 
 /**
@@ -1251,26 +994,30 @@ void gfs2_glock_dq(struct gfs2_holder *gh)
 	struct gfs2_glock *gl = gh->gh_gl;
 	const struct gfs2_glock_operations *glops = gl->gl_ops;
 	unsigned delay = 0;
+	int fast_path = 0;
 
+	spin_lock(&gl->gl_spin);
 	if (gh->gh_flags & GL_NOCACHE)
 		handle_callback(gl, LM_ST_UNLOCKED, 0, 0);
 
-	gfs2_glmutex_lock(gl);
-
-	spin_lock(&gl->gl_spin);
 	list_del_init(&gh->gh_list);
-
-	if (list_empty(&gl->gl_holders)) {
+	if (find_first_holder(gl) == NULL) {
 		if (glops->go_unlock) {
+			GLOCK_BUG_ON(gl, test_and_set_bit(GLF_LOCK, &gl->gl_flags));
 			spin_unlock(&gl->gl_spin);
 			glops->go_unlock(gh);
 			spin_lock(&gl->gl_spin);
+			clear_bit(GLF_LOCK, &gl->gl_flags);
 		}
 		gl->gl_stamp = jiffies;
+		if (list_empty(&gl->gl_holders) &&
+		    !test_bit(GLF_PENDING_DEMOTE, &gl->gl_flags) &&
+		    !test_bit(GLF_DEMOTE, &gl->gl_flags))
+			fast_path = 1;
 	}
-
-	clear_bit(GLF_LOCK, &gl->gl_flags);
 	spin_unlock(&gl->gl_spin);
+	if (likely(fast_path))
+		return;
 
 	gfs2_glock_hold(gl);
 	if (test_bit(GLF_PENDING_DEMOTE, &gl->gl_flags) &&
@@ -1454,6 +1201,8 @@ void gfs2_glock_dq_uninit_m(unsigned int num_gh, struct gfs2_holder *ghs)
 static int gfs2_lm_hold_lvb(struct gfs2_sbd *sdp, void *lock, char **lvbp)
 {
 	int error = -EIO;
+	if (!sdp->sd_lockstruct.ls_ops->lm_hold_lvb)
+		return 0;
 	if (likely(!test_bit(SDF_SHUTDOWN, &sdp->sd_flags)))
 		error = sdp->sd_lockstruct.ls_ops->lm_hold_lvb(lock, lvbp);
 	return error;
@@ -1469,20 +1218,14 @@ int gfs2_lvb_hold(struct gfs2_glock *gl)
 {
 	int error;
 
-	gfs2_glmutex_lock(gl);
-
 	if (!atomic_read(&gl->gl_lvb_count)) {
 		error = gfs2_lm_hold_lvb(gl->gl_sbd, gl->gl_lock, &gl->gl_lvb);
-		if (error) {
-			gfs2_glmutex_unlock(gl);
+		if (error) 
 			return error;
-		}
 		gfs2_glock_hold(gl);
 	}
 	atomic_inc(&gl->gl_lvb_count);
 
-	gfs2_glmutex_unlock(gl);
-
 	return 0;
 }
 
@@ -1497,17 +1240,13 @@ void gfs2_lvb_unhold(struct gfs2_glock *gl)
 	struct gfs2_sbd *sdp = gl->gl_sbd;
 
 	gfs2_glock_hold(gl);
-	gfs2_glmutex_lock(gl);
-
 	gfs2_assert(gl->gl_sbd, atomic_read(&gl->gl_lvb_count) > 0);
 	if (atomic_dec_and_test(&gl->gl_lvb_count)) {
-		if (likely(!test_bit(SDF_SHUTDOWN, &sdp->sd_flags)))
+		if (sdp->sd_lockstruct.ls_ops->lm_unhold_lvb)
 			sdp->sd_lockstruct.ls_ops->lm_unhold_lvb(gl->gl_lock, gl->gl_lvb);
 		gl->gl_lvb = NULL;
 		gfs2_glock_put(gl);
 	}
-
-	gfs2_glmutex_unlock(gl);
 	gfs2_glock_put(gl);
 }
 
@@ -1527,7 +1266,9 @@ static void blocking_cb(struct gfs2_sbd *sdp, struct lm_lockname *name,
 	if (time_before(now, holdtime))
 		delay = holdtime - now;
 
+	spin_lock(&gl->gl_spin);
 	handle_callback(gl, state, 1, delay);
+	spin_unlock(&gl->gl_spin);
 	if (queue_delayed_work(glock_workqueue, &gl->gl_work, delay) == 0)
 		gfs2_glock_put(gl);
 }
@@ -1568,7 +1309,8 @@ void gfs2_glock_cb(void *cb_data, unsigned int type, void *data)
 		gl = gfs2_glock_find(sdp, &async->lc_name);
 		if (gfs2_assert_warn(sdp, gl))
 			return;
-		xmote_bh(gl, async->lc_ret);
+		gl->gl_reply = async->lc_ret;
+		set_bit(GLF_REPLY_PENDING, &gl->gl_flags);
 		if (queue_delayed_work(glock_workqueue, &gl->gl_work, 0) == 0)
 			gfs2_glock_put(gl);
 		up_read(&gfs2_umount_flush_sem);
@@ -1581,11 +1323,6 @@ void gfs2_glock_cb(void *cb_data, unsigned int type, void *data)
 			wake_up_process(sdp->sd_recoverd_process);
 		return;
 
-	case LM_CB_DROPLOCKS:
-		gfs2_gl_hash_clear(sdp, NO_WAIT);
-		gfs2_quota_scan(sdp);
-		return;
-
 	default:
 		gfs2_assert_warn(sdp, 0);
 		return;
@@ -1646,6 +1383,7 @@ void gfs2_glock_schedule_for_reclaim(struct gfs2_glock *gl)
 void gfs2_reclaim_glock(struct gfs2_sbd *sdp)
 {
 	struct gfs2_glock *gl;
+	int done_callback = 0;
 
 	spin_lock(&sdp->sd_reclaim_lock);
 	if (list_empty(&sdp->sd_reclaim_list)) {
@@ -1660,14 +1398,16 @@ void gfs2_reclaim_glock(struct gfs2_sbd *sdp)
 	atomic_dec(&sdp->sd_reclaim_count);
 	atomic_inc(&sdp->sd_reclaimed);
 
-	if (gfs2_glmutex_trylock(gl)) {
-		if (list_empty(&gl->gl_holders) &&
-		    gl->gl_state != LM_ST_UNLOCKED && demote_ok(gl))
-			handle_callback(gl, LM_ST_UNLOCKED, 0, 0);
-		gfs2_glmutex_unlock(gl);
+	spin_lock(&gl->gl_spin);
+	if (find_first_holder(gl) == NULL &&
+	    gl->gl_state != LM_ST_UNLOCKED && demote_ok(gl)) {
+		handle_callback(gl, LM_ST_UNLOCKED, 0, 0);
+		done_callback = 1;
 	}
-
-	gfs2_glock_put(gl);
+	spin_unlock(&gl->gl_spin);
+	if (!done_callback ||
+	    queue_delayed_work(glock_workqueue, &gl->gl_work, 0) == 0)
+		gfs2_glock_put(gl);
 }
 
 /**
@@ -1724,18 +1464,14 @@ static void scan_glock(struct gfs2_glock *gl)
 {
 	if (gl->gl_ops == &gfs2_inode_glops && gl->gl_object)
 		return;
+	if (test_bit(GLF_LOCK, &gl->gl_flags))
+		return;
 
-	if (gfs2_glmutex_trylock(gl)) {
-		if (list_empty(&gl->gl_holders) &&
-		    gl->gl_state != LM_ST_UNLOCKED && demote_ok(gl))
-			goto out_schedule;
-		gfs2_glmutex_unlock(gl);
-	}
-	return;
-
-out_schedule:
-	gfs2_glmutex_unlock(gl);
-	gfs2_glock_schedule_for_reclaim(gl);
+	spin_lock(&gl->gl_spin);
+	if (find_first_holder(gl) == NULL &&
+	    gl->gl_state != LM_ST_UNLOCKED && demote_ok(gl))
+		gfs2_glock_schedule_for_reclaim(gl);
+	spin_unlock(&gl->gl_spin);
 }
 
 /**
@@ -1760,12 +1496,13 @@ static void clear_glock(struct gfs2_glock *gl)
 		spin_unlock(&sdp->sd_reclaim_lock);
 	}
 
-	if (gfs2_glmutex_trylock(gl)) {
-		if (list_empty(&gl->gl_holders) &&
-		    gl->gl_state != LM_ST_UNLOCKED)
-			handle_callback(gl, LM_ST_UNLOCKED, 0, 0);
-		gfs2_glmutex_unlock(gl);
-	}
+	spin_lock(&gl->gl_spin);
+	if (find_first_holder(gl) == NULL && gl->gl_state != LM_ST_UNLOCKED)
+		handle_callback(gl, LM_ST_UNLOCKED, 0, 0);
+	spin_unlock(&gl->gl_spin);
+	gfs2_glock_hold(gl);
+	if (queue_delayed_work(glock_workqueue, &gl->gl_work, 0) == 0)
+		gfs2_glock_put(gl);
 }
 
 /**
@@ -1773,11 +1510,10 @@ static void clear_glock(struct gfs2_glock *gl)
  * @sdp: the filesystem
  * @wait: wait until it's all gone
  *
- * Called when unmounting the filesystem, or when inter-node lock manager
- * requests DROPLOCKS because it is running out of capacity.
+ * Called when unmounting the filesystem.
  */
 
-void gfs2_gl_hash_clear(struct gfs2_sbd *sdp, int wait)
+void gfs2_gl_hash_clear(struct gfs2_sbd *sdp)
 {
 	unsigned long t;
 	unsigned int x;
@@ -1792,7 +1528,7 @@ void gfs2_gl_hash_clear(struct gfs2_sbd *sdp, int wait)
 				cont = 1;
 		}
 
-		if (!wait || !cont)
+		if (!cont)
 			break;
 
 		if (time_after_eq(jiffies,
@@ -1810,180 +1546,164 @@ void gfs2_gl_hash_clear(struct gfs2_sbd *sdp, int wait)
 	}
 }
 
-/*
- *  Diagnostic routines to help debug distributed deadlock
- */
-
-static void gfs2_print_symbol(struct glock_iter *gi, const char *fmt,
-                              unsigned long address)
+static const char *state2str(unsigned state)
 {
-	char buffer[KSYM_SYMBOL_LEN];
-
-	sprint_symbol(buffer, address);
-	print_dbg(gi, fmt, buffer);
+	switch(state) {
+	case LM_ST_UNLOCKED:
+		return "UN";
+	case LM_ST_SHARED:
+		return "SH";
+	case LM_ST_DEFERRED:
+		return "DF";
+	case LM_ST_EXCLUSIVE:
+		return "EX";
+	}
+	return "??";
+}
+
+static const char *hflags2str(char *buf, unsigned flags, unsigned long iflags)
+{
+	char *p = buf;
+	if (flags & LM_FLAG_TRY)
+		*p++ = 't';
+	if (flags & LM_FLAG_TRY_1CB)
+		*p++ = 'T';
+	if (flags & LM_FLAG_NOEXP)
+		*p++ = 'e';
+	if (flags & LM_FLAG_ANY)
+		*p++ = 'a';
+	if (flags & LM_FLAG_PRIORITY)
+		*p++ = 'p';
+	if (flags & GL_ASYNC)
+		*p++ = 'a';
+	if (flags & GL_EXACT)
+		*p++ = 'E';
+	if (flags & GL_ATIME)
+		*p++ = 'a';
+	if (flags & GL_NOCACHE)
+		*p++ = 'c';
+	if (test_bit(HIF_HOLDER, &iflags))
+		*p++ = 'H';
+	if (test_bit(HIF_WAIT, &iflags))
+		*p++ = 'W';
+	if (test_bit(HIF_FIRST, &iflags))
+		*p++ = 'F';
+	*p = 0;
+	return buf;
 }
 
 /**
  * dump_holder - print information about a glock holder
- * @str: a string naming the type of holder
+ * @seq: the seq_file struct
  * @gh: the glock holder
  *
  * Returns: 0 on success, -ENOBUFS when we run out of space
  */
 
-static int dump_holder(struct glock_iter *gi, char *str,
-		       struct gfs2_holder *gh)
+static int dump_holder(struct seq_file *seq, const struct gfs2_holder *gh)
 {
-	unsigned int x;
-	struct task_struct *gh_owner;
+	struct task_struct *gh_owner = NULL;
+	char buffer[KSYM_SYMBOL_LEN];
+	char flags_buf[32];
 
-	print_dbg(gi, "  %s\n", str);
-	if (gh->gh_owner_pid) {
-		print_dbg(gi, "    owner = %ld ",
-				(long)pid_nr(gh->gh_owner_pid));
+	sprint_symbol(buffer, gh->gh_ip);
+	if (gh->gh_owner_pid)
 		gh_owner = pid_task(gh->gh_owner_pid, PIDTYPE_PID);
-		if (gh_owner)
-			print_dbg(gi, "(%s)\n", gh_owner->comm);
-		else
-			print_dbg(gi, "(ended)\n");
-	} else
-		print_dbg(gi, "    owner = -1\n");
-	print_dbg(gi, "    gh_state = %u\n", gh->gh_state);
-	print_dbg(gi, "    gh_flags =");
-	for (x = 0; x < 32; x++)
-		if (gh->gh_flags & (1 << x))
-			print_dbg(gi, " %u", x);
-	print_dbg(gi, " \n");
-	print_dbg(gi, "    error = %d\n", gh->gh_error);
-	print_dbg(gi, "    gh_iflags =");
-	for (x = 0; x < 32; x++)
-		if (test_bit(x, &gh->gh_iflags))
-			print_dbg(gi, " %u", x);
-	print_dbg(gi, " \n");
-        gfs2_print_symbol(gi, "    initialized at: %s\n", gh->gh_ip);
-
+	gfs2_print_dbg(seq, " H: s:%s f:%s e:%d p:%ld [%s] %s\n",
+		  state2str(gh->gh_state),
+		  hflags2str(flags_buf, gh->gh_flags, gh->gh_iflags),
+		  gh->gh_error, 
+		  gh->gh_owner_pid ? (long)pid_nr(gh->gh_owner_pid) : -1,
+		  gh_owner ? gh_owner->comm : "(ended)", buffer);
 	return 0;
 }
 
-/**
- * dump_inode - print information about an inode
- * @ip: the inode
- *
- * Returns: 0 on success, -ENOBUFS when we run out of space
- */
-
-static int dump_inode(struct glock_iter *gi, struct gfs2_inode *ip)
-{
-	unsigned int x;
-
-	print_dbg(gi, "  Inode:\n");
-	print_dbg(gi, "    num = %llu/%llu\n",
-		  (unsigned long long)ip->i_no_formal_ino,
-		  (unsigned long long)ip->i_no_addr);
-	print_dbg(gi, "    type = %u\n", IF2DT(ip->i_inode.i_mode));
-	print_dbg(gi, "    i_flags =");
-	for (x = 0; x < 32; x++)
-		if (test_bit(x, &ip->i_flags))
-			print_dbg(gi, " %u", x);
-	print_dbg(gi, " \n");
-	return 0;
+static const char *gflags2str(char *buf, const unsigned long *gflags)
+{
+	char *p = buf;
+	if (test_bit(GLF_LOCK, gflags))
+		*p++ = 'l';
+	if (test_bit(GLF_STICKY, gflags))
+		*p++ = 's';
+	if (test_bit(GLF_DEMOTE, gflags))
+		*p++ = 'D';
+	if (test_bit(GLF_PENDING_DEMOTE, gflags))
+		*p++ = 'd';
+	if (test_bit(GLF_DEMOTE_IN_PROGRESS, gflags))
+		*p++ = 'p';
+	if (test_bit(GLF_DIRTY, gflags))
+		*p++ = 'y';
+	if (test_bit(GLF_LFLUSH, gflags))
+		*p++ = 'f';
+	if (test_bit(GLF_INVALIDATE_IN_PROGRESS, gflags))
+		*p++ = 'i';
+	if (test_bit(GLF_REPLY_PENDING, gflags))
+		*p++ = 'r';
+	*p = 0;
+	return buf;
 }
 
 /**
- * dump_glock - print information about a glock
+ * __dump_glock - print information about a glock
+ * @seq: The seq_file struct
  * @gl: the glock
- * @count: where we are in the buffer
+ *
+ * The file format is as follows:
+ * One line per object, capital letters are used to indicate objects
+ * G = glock, I = Inode, R = rgrp, H = holder. Glocks are not indented,
+ * other objects are indented by a single space and follow the glock to
+ * which they are related. Fields are indicated by lower case letters
+ * followed by a colon and the field value, except for strings which are in
+ * [] so that its possible to see if they are composed of spaces for
+ * example. The field's are n = number (id of the object), f = flags,
+ * t = type, s = state, r = refcount, e = error, p = pid.
  *
  * Returns: 0 on success, -ENOBUFS when we run out of space
  */
 
-static int dump_glock(struct glock_iter *gi, struct gfs2_glock *gl)
+static int __dump_glock(struct seq_file *seq, const struct gfs2_glock *gl)
 {
-	struct gfs2_holder *gh;
-	unsigned int x;
-	int error = -ENOBUFS;
-	struct task_struct *gl_owner;
+	const struct gfs2_glock_operations *glops = gl->gl_ops;
+	unsigned long long dtime;
+	const struct gfs2_holder *gh;
+	char gflags_buf[32];
+	int error = 0;
 
-	spin_lock(&gl->gl_spin);
+	dtime = jiffies - gl->gl_demote_time;
+	dtime *= 1000000/HZ; /* demote time in uSec */
+	if (!test_bit(GLF_DEMOTE, &gl->gl_flags))
+		dtime = 0;
+	gfs2_print_dbg(seq, "G:  s:%s n:%u/%llu f:%s t:%s d:%s/%llu l:%d a:%d r:%d\n",
+		  state2str(gl->gl_state),
+		  gl->gl_name.ln_type,
+		  (unsigned long long)gl->gl_name.ln_number,
+		  gflags2str(gflags_buf, &gl->gl_flags),
+		  state2str(gl->gl_target),
+		  state2str(gl->gl_demote_state), dtime,
+		  atomic_read(&gl->gl_lvb_count),
+		  atomic_read(&gl->gl_ail_count),
+		  atomic_read(&gl->gl_ref));
 
-	print_dbg(gi, "Glock 0x%p (%u, 0x%llx)\n", gl, gl->gl_name.ln_type,
-		   (unsigned long long)gl->gl_name.ln_number);
-	print_dbg(gi, "  gl_flags =");
-	for (x = 0; x < 32; x++) {
-		if (test_bit(x, &gl->gl_flags))
-			print_dbg(gi, " %u", x);
-	}
-	if (!test_bit(GLF_LOCK, &gl->gl_flags))
-		print_dbg(gi, " (unlocked)");
-	print_dbg(gi, " \n");
-	print_dbg(gi, "  gl_ref = %d\n", atomic_read(&gl->gl_ref));
-	print_dbg(gi, "  gl_state = %u\n", gl->gl_state);
-	if (gl->gl_owner_pid) {
-		gl_owner = pid_task(gl->gl_owner_pid, PIDTYPE_PID);
-		if (gl_owner)
-			print_dbg(gi, "  gl_owner = pid %d (%s)\n",
-				  pid_nr(gl->gl_owner_pid), gl_owner->comm);
-		else
-			print_dbg(gi, "  gl_owner = %d (ended)\n",
-				  pid_nr(gl->gl_owner_pid));
-	} else
-		print_dbg(gi, "  gl_owner = -1\n");
-	print_dbg(gi, "  gl_ip = %lu\n", gl->gl_ip);
-	print_dbg(gi, "  req_gh = %s\n", (gl->gl_req_gh) ? "yes" : "no");
-	print_dbg(gi, "  lvb_count = %d\n", atomic_read(&gl->gl_lvb_count));
-	print_dbg(gi, "  object = %s\n", (gl->gl_object) ? "yes" : "no");
-	print_dbg(gi, "  reclaim = %s\n",
-		   (list_empty(&gl->gl_reclaim)) ? "no" : "yes");
-	if (gl->gl_aspace)
-		print_dbg(gi, "  aspace = 0x%p nrpages = %lu\n", gl->gl_aspace,
-			   gl->gl_aspace->i_mapping->nrpages);
-	else
-		print_dbg(gi, "  aspace = no\n");
-	print_dbg(gi, "  ail = %d\n", atomic_read(&gl->gl_ail_count));
-	if (gl->gl_req_gh) {
-		error = dump_holder(gi, "Request", gl->gl_req_gh);
-		if (error)
-			goto out;
-	}
 	list_for_each_entry(gh, &gl->gl_holders, gh_list) {
-		error = dump_holder(gi, "Holder", gh);
+		error = dump_holder(seq, gh);
 		if (error)
 			goto out;
 	}
-	list_for_each_entry(gh, &gl->gl_waiters1, gh_list) {
-		error = dump_holder(gi, "Waiter1", gh);
-		if (error)
-			goto out;
-	}
-	list_for_each_entry(gh, &gl->gl_waiters3, gh_list) {
-		error = dump_holder(gi, "Waiter3", gh);
-		if (error)
-			goto out;
-	}
-	if (test_bit(GLF_DEMOTE, &gl->gl_flags)) {
-		print_dbg(gi, "  Demotion req to state %u (%llu uS ago)\n",
-			  gl->gl_demote_state, (unsigned long long)
-			  (jiffies - gl->gl_demote_time)*(1000000/HZ));
-	}
-	if (gl->gl_ops == &gfs2_inode_glops && gl->gl_object) {
-		if (!test_bit(GLF_LOCK, &gl->gl_flags) &&
-			list_empty(&gl->gl_holders)) {
-			error = dump_inode(gi, gl->gl_object);
-			if (error)
-				goto out;
-		} else {
-			error = -ENOBUFS;
-			print_dbg(gi, "  Inode: busy\n");
-		}
-	}
-
-	error = 0;
-
+	if (gl->gl_state != LM_ST_UNLOCKED && glops->go_dump)
+		error = glops->go_dump(seq, gl);
 out:
-	spin_unlock(&gl->gl_spin);
 	return error;
 }
 
+static int dump_glock(struct seq_file *seq, struct gfs2_glock *gl)
+{
+	int ret;
+	spin_lock(&gl->gl_spin);
+	ret = __dump_glock(seq, gl);
+	spin_unlock(&gl->gl_spin);
+	return ret;
+}
+
 /**
  * gfs2_dump_lockstate - print out the current lockstate
  * @sdp: the filesystem
@@ -2086,7 +1806,7 @@ void gfs2_glock_exit(void)
 module_param(scand_secs, uint, S_IRUGO|S_IWUSR);
 MODULE_PARM_DESC(scand_secs, "The number of seconds between scand runs");
 
-static int gfs2_glock_iter_next(struct glock_iter *gi)
+static int gfs2_glock_iter_next(struct gfs2_glock_iter *gi)
 {
 	struct gfs2_glock *gl;
 
@@ -2104,7 +1824,7 @@ restart:
 		gfs2_glock_put(gl);
 	if (gl && gi->gl == NULL)
 		gi->hash++;
-	while(gi->gl == NULL) {
+	while (gi->gl == NULL) {
 		if (gi->hash >= GFS2_GL_HASH_SIZE)
 			return 1;
 		read_lock(gl_lock_addr(gi->hash));
@@ -2122,58 +1842,34 @@ restart:
 	return 0;
 }
 
-static void gfs2_glock_iter_free(struct glock_iter *gi)
+static void gfs2_glock_iter_free(struct gfs2_glock_iter *gi)
 {
 	if (gi->gl)
 		gfs2_glock_put(gi->gl);
-	kfree(gi);
-}
-
-static struct glock_iter *gfs2_glock_iter_init(struct gfs2_sbd *sdp)
-{
-	struct glock_iter *gi;
-
-	gi = kmalloc(sizeof (*gi), GFP_KERNEL);
-	if (!gi)
-		return NULL;
-
-	gi->sdp = sdp;
-	gi->hash = 0;
-	gi->seq = NULL;
 	gi->gl = NULL;
-	memset(gi->string, 0, sizeof(gi->string));
-
-	if (gfs2_glock_iter_next(gi)) {
-		gfs2_glock_iter_free(gi);
-		return NULL;
-	}
-
-	return gi;
 }
 
-static void *gfs2_glock_seq_start(struct seq_file *file, loff_t *pos)
+static void *gfs2_glock_seq_start(struct seq_file *seq, loff_t *pos)
 {
-	struct glock_iter *gi;
+	struct gfs2_glock_iter *gi = seq->private;
 	loff_t n = *pos;
 
-	gi = gfs2_glock_iter_init(file->private);
-	if (!gi)
-		return NULL;
+	gi->hash = 0;
 
-	while(n--) {
+	do {
 		if (gfs2_glock_iter_next(gi)) {
 			gfs2_glock_iter_free(gi);
 			return NULL;
 		}
-	}
+	} while (n--);
 
-	return gi;
+	return gi->gl;
 }
 
-static void *gfs2_glock_seq_next(struct seq_file *file, void *iter_ptr,
+static void *gfs2_glock_seq_next(struct seq_file *seq, void *iter_ptr,
 				 loff_t *pos)
 {
-	struct glock_iter *gi = iter_ptr;
+	struct gfs2_glock_iter *gi = seq->private;
 
 	(*pos)++;
 
@@ -2182,24 +1878,18 @@ static void *gfs2_glock_seq_next(struct seq_file *file, void *iter_ptr,
 		return NULL;
 	}
 
-	return gi;
+	return gi->gl;
 }
 
-static void gfs2_glock_seq_stop(struct seq_file *file, void *iter_ptr)
+static void gfs2_glock_seq_stop(struct seq_file *seq, void *iter_ptr)
 {
-	struct glock_iter *gi = iter_ptr;
-	if (gi)
-		gfs2_glock_iter_free(gi);
+	struct gfs2_glock_iter *gi = seq->private;
+	gfs2_glock_iter_free(gi);
 }
 
-static int gfs2_glock_seq_show(struct seq_file *file, void *iter_ptr)
+static int gfs2_glock_seq_show(struct seq_file *seq, void *iter_ptr)
 {
-	struct glock_iter *gi = iter_ptr;
-
-	gi->seq = file;
-	dump_glock(gi, gi->gl);
-
-	return 0;
+	return dump_glock(seq, iter_ptr);
 }
 
 static const struct seq_operations gfs2_glock_seq_ops = {
@@ -2211,17 +1901,14 @@ static const struct seq_operations gfs2_glock_seq_ops = {
 
 static int gfs2_debugfs_open(struct inode *inode, struct file *file)
 {
-	struct seq_file *seq;
-	int ret;
-
-	ret = seq_open(file, &gfs2_glock_seq_ops);
-	if (ret)
-		return ret;
-
-	seq = file->private_data;
-	seq->private = inode->i_private;
-
-	return 0;
+	int ret = seq_open_private(file, &gfs2_glock_seq_ops,
+				   sizeof(struct gfs2_glock_iter));
+	if (ret == 0) {
+		struct seq_file *seq = file->private_data;
+		struct gfs2_glock_iter *gi = seq->private;
+		gi->sdp = inode->i_private;
+	}
+	return ret;
 }
 
 static const struct file_operations gfs2_debug_fops = {
@@ -2229,7 +1916,7 @@ static const struct file_operations gfs2_debug_fops = {
 	.open    = gfs2_debugfs_open,
 	.read    = seq_read,
 	.llseek  = seq_lseek,
-	.release = seq_release
+	.release = seq_release_private,
 };
 
 int gfs2_create_debugfs_file(struct gfs2_sbd *sdp)
diff --git a/fs/gfs2/glock.h b/fs/gfs2/glock.h
index cdad3e6f815..971d92af70f 100644
--- a/fs/gfs2/glock.h
+++ b/fs/gfs2/glock.h
@@ -26,11 +26,8 @@
 #define GL_SKIP			0x00000100
 #define GL_ATIME		0x00000200
 #define GL_NOCACHE		0x00000400
-#define GL_FLOCK		0x00000800
-#define GL_NOCANCEL		0x00001000
 
 #define GLR_TRYFAILED		13
-#define GLR_CANCELED		14
 
 static inline struct gfs2_holder *gfs2_glock_is_locked_by_me(struct gfs2_glock *gl)
 {
@@ -41,6 +38,8 @@ static inline struct gfs2_holder *gfs2_glock_is_locked_by_me(struct gfs2_glock *
 	spin_lock(&gl->gl_spin);
 	pid = task_pid(current);
 	list_for_each_entry(gh, &gl->gl_holders, gh_list) {
+		if (!test_bit(HIF_HOLDER, &gh->gh_iflags))
+			break;
 		if (gh->gh_owner_pid == pid)
 			goto out;
 	}
@@ -70,7 +69,7 @@ static inline int gfs2_glock_is_blocking(struct gfs2_glock *gl)
 {
 	int ret;
 	spin_lock(&gl->gl_spin);
-	ret = test_bit(GLF_DEMOTE, &gl->gl_flags) || !list_empty(&gl->gl_waiters3);
+	ret = test_bit(GLF_DEMOTE, &gl->gl_flags);
 	spin_unlock(&gl->gl_spin);
 	return ret;
 }
@@ -98,6 +97,7 @@ int gfs2_glock_nq_num(struct gfs2_sbd *sdp,
 int gfs2_glock_nq_m(unsigned int num_gh, struct gfs2_holder *ghs);
 void gfs2_glock_dq_m(unsigned int num_gh, struct gfs2_holder *ghs);
 void gfs2_glock_dq_uninit_m(unsigned int num_gh, struct gfs2_holder *ghs);
+void gfs2_print_dbg(struct seq_file *seq, const char *fmt, ...);
 
 /**
  * gfs2_glock_nq_init - intialize a holder and enqueue it on a glock
@@ -130,10 +130,9 @@ int gfs2_lvb_hold(struct gfs2_glock *gl);
 void gfs2_lvb_unhold(struct gfs2_glock *gl);
 
 void gfs2_glock_cb(void *cb_data, unsigned int type, void *data);
-
 void gfs2_glock_schedule_for_reclaim(struct gfs2_glock *gl);
 void gfs2_reclaim_glock(struct gfs2_sbd *sdp);
-void gfs2_gl_hash_clear(struct gfs2_sbd *sdp, int wait);
+void gfs2_gl_hash_clear(struct gfs2_sbd *sdp);
 
 int __init gfs2_glock_init(void);
 void gfs2_glock_exit(void);
diff --git a/fs/gfs2/glops.c b/fs/gfs2/glops.c
index 07d84d16cda..c6c318c2a0f 100644
--- a/fs/gfs2/glops.c
+++ b/fs/gfs2/glops.c
@@ -13,6 +13,7 @@
 #include <linux/buffer_head.h>
 #include <linux/gfs2_ondisk.h>
 #include <linux/lm_interface.h>
+#include <linux/bio.h>
 
 #include "gfs2.h"
 #include "incore.h"
@@ -172,26 +173,6 @@ static void inode_go_sync(struct gfs2_glock *gl)
 }
 
 /**
- * inode_go_xmote_bh - After promoting/demoting a glock
- * @gl: the glock
- *
- */
-
-static void inode_go_xmote_bh(struct gfs2_glock *gl)
-{
-	struct gfs2_holder *gh = gl->gl_req_gh;
-	struct buffer_head *bh;
-	int error;
-
-	if (gl->gl_state != LM_ST_UNLOCKED &&
-	    (!gh || !(gh->gh_flags & GL_SKIP))) {
-		error = gfs2_meta_read(gl, gl->gl_name.ln_number, 0, &bh);
-		if (!error)
-			brelse(bh);
-	}
-}
-
-/**
  * inode_go_inval - prepare a inode glock to be released
  * @gl: the glock
  * @flags:
@@ -267,6 +248,26 @@ static int inode_go_lock(struct gfs2_holder *gh)
 }
 
 /**
+ * inode_go_dump - print information about an inode
+ * @seq: The iterator
+ * @ip: the inode
+ *
+ * Returns: 0 on success, -ENOBUFS when we run out of space
+ */
+
+static int inode_go_dump(struct seq_file *seq, const struct gfs2_glock *gl)
+{
+	const struct gfs2_inode *ip = gl->gl_object;
+	if (ip == NULL)
+		return 0;
+	gfs2_print_dbg(seq, " I: n:%llu/%llu t:%u f:0x%08lx\n",
+		  (unsigned long long)ip->i_no_formal_ino,
+		  (unsigned long long)ip->i_no_addr,
+		  IF2DT(ip->i_inode.i_mode), ip->i_flags);
+	return 0;
+}
+
+/**
  * rgrp_go_demote_ok - Check to see if it's ok to unlock a RG's glock
  * @gl: the glock
  *
@@ -306,6 +307,22 @@ static void rgrp_go_unlock(struct gfs2_holder *gh)
 }
 
 /**
+ * rgrp_go_dump - print out an rgrp
+ * @seq: The iterator
+ * @gl: The glock in question
+ *
+ */
+
+static int rgrp_go_dump(struct seq_file *seq, const struct gfs2_glock *gl)
+{
+	const struct gfs2_rgrpd *rgd = gl->gl_object;
+	if (rgd == NULL)
+		return 0;
+	gfs2_print_dbg(seq, " R: n:%llu\n", (unsigned long long)rgd->rd_addr);
+	return 0;
+}
+
+/**
  * trans_go_sync - promote/demote the transaction glock
  * @gl: the glock
  * @state: the requested state
@@ -330,7 +347,7 @@ static void trans_go_sync(struct gfs2_glock *gl)
  *
  */
 
-static void trans_go_xmote_bh(struct gfs2_glock *gl)
+static int trans_go_xmote_bh(struct gfs2_glock *gl, struct gfs2_holder *gh)
 {
 	struct gfs2_sbd *sdp = gl->gl_sbd;
 	struct gfs2_inode *ip = GFS2_I(sdp->sd_jdesc->jd_inode);
@@ -338,8 +355,7 @@ static void trans_go_xmote_bh(struct gfs2_glock *gl)
 	struct gfs2_log_header_host head;
 	int error;
 
-	if (gl->gl_state != LM_ST_UNLOCKED &&
-	    test_bit(SDF_JOURNAL_LIVE, &sdp->sd_flags)) {
+	if (test_bit(SDF_JOURNAL_LIVE, &sdp->sd_flags)) {
 		j_gl->gl_ops->go_inval(j_gl, DIO_METADATA);
 
 		error = gfs2_find_jhead(sdp->sd_jdesc, &head);
@@ -354,6 +370,7 @@ static void trans_go_xmote_bh(struct gfs2_glock *gl)
 			gfs2_log_pointers_init(sdp, head.lh_blkno);
 		}
 	}
+	return 0;
 }
 
 /**
@@ -375,12 +392,12 @@ const struct gfs2_glock_operations gfs2_meta_glops = {
 
 const struct gfs2_glock_operations gfs2_inode_glops = {
 	.go_xmote_th = inode_go_sync,
-	.go_xmote_bh = inode_go_xmote_bh,
 	.go_inval = inode_go_inval,
 	.go_demote_ok = inode_go_demote_ok,
 	.go_lock = inode_go_lock,
+	.go_dump = inode_go_dump,
 	.go_type = LM_TYPE_INODE,
-	.go_min_hold_time = HZ / 10,
+	.go_min_hold_time = HZ / 5,
 };
 
 const struct gfs2_glock_operations gfs2_rgrp_glops = {
@@ -389,8 +406,9 @@ const struct gfs2_glock_operations gfs2_rgrp_glops = {
 	.go_demote_ok = rgrp_go_demote_ok,
 	.go_lock = rgrp_go_lock,
 	.go_unlock = rgrp_go_unlock,
+	.go_dump = rgrp_go_dump,
 	.go_type = LM_TYPE_RGRP,
-	.go_min_hold_time = HZ / 10,
+	.go_min_hold_time = HZ / 5,
 };
 
 const struct gfs2_glock_operations gfs2_trans_glops = {
diff --git a/fs/gfs2/incore.h b/fs/gfs2/incore.h
index eabe5eac41d..448697a5c46 100644
--- a/fs/gfs2/incore.h
+++ b/fs/gfs2/incore.h
@@ -77,7 +77,6 @@ struct gfs2_rgrp_host {
 struct gfs2_rgrpd {
 	struct list_head rd_list;	/* Link with superblock */
 	struct list_head rd_list_mru;
-	struct list_head rd_recent;	/* Recently used rgrps */
 	struct gfs2_glock *rd_gl;	/* Glock for this rgrp */
 	u64 rd_addr;			/* grp block disk address */
 	u64 rd_data0;			/* first data location */
@@ -128,20 +127,20 @@ struct gfs2_bufdata {
 
 struct gfs2_glock_operations {
 	void (*go_xmote_th) (struct gfs2_glock *gl);
-	void (*go_xmote_bh) (struct gfs2_glock *gl);
+	int (*go_xmote_bh) (struct gfs2_glock *gl, struct gfs2_holder *gh);
 	void (*go_inval) (struct gfs2_glock *gl, int flags);
 	int (*go_demote_ok) (struct gfs2_glock *gl);
 	int (*go_lock) (struct gfs2_holder *gh);
 	void (*go_unlock) (struct gfs2_holder *gh);
+	int (*go_dump)(struct seq_file *seq, const struct gfs2_glock *gl);
 	const int go_type;
 	const unsigned long go_min_hold_time;
 };
 
 enum {
 	/* States */
-	HIF_HOLDER		= 6,
+	HIF_HOLDER		= 6,  /* Set for gh that "holds" the glock */
 	HIF_FIRST		= 7,
-	HIF_ABORTED		= 9,
 	HIF_WAIT		= 10,
 };
 
@@ -154,20 +153,20 @@ struct gfs2_holder {
 	unsigned gh_flags;
 
 	int gh_error;
-	unsigned long gh_iflags;
+	unsigned long gh_iflags; /* HIF_... */
 	unsigned long gh_ip;
 };
 
 enum {
-	GLF_LOCK		= 1,
-	GLF_STICKY		= 2,
-	GLF_DEMOTE		= 3,
-	GLF_PENDING_DEMOTE	= 4,
-	GLF_DIRTY		= 5,
-	GLF_DEMOTE_IN_PROGRESS	= 6,
-	GLF_LFLUSH		= 7,
-	GLF_WAITERS2		= 8,
-	GLF_CONV_DEADLK		= 9,
+	GLF_LOCK			= 1,
+	GLF_STICKY			= 2,
+	GLF_DEMOTE			= 3,
+	GLF_PENDING_DEMOTE		= 4,
+	GLF_DEMOTE_IN_PROGRESS		= 5,
+	GLF_DIRTY			= 6,
+	GLF_LFLUSH			= 7,
+	GLF_INVALIDATE_IN_PROGRESS	= 8,
+	GLF_REPLY_PENDING		= 9,
 };
 
 struct gfs2_glock {
@@ -179,19 +178,14 @@ struct gfs2_glock {
 	spinlock_t gl_spin;
 
 	unsigned int gl_state;
+	unsigned int gl_target;
+	unsigned int gl_reply;
 	unsigned int gl_hash;
 	unsigned int gl_demote_state; /* state requested by remote node */
 	unsigned long gl_demote_time; /* time of first demote request */
-	struct pid *gl_owner_pid;
-	unsigned long gl_ip;
 	struct list_head gl_holders;
-	struct list_head gl_waiters1;	/* HIF_MUTEX */
-	struct list_head gl_waiters3;	/* HIF_PROMOTE */
 
 	const struct gfs2_glock_operations *gl_ops;
-
-	struct gfs2_holder *gl_req_gh;
-
 	void *gl_lock;
 	char *gl_lvb;
 	atomic_t gl_lvb_count;
@@ -427,7 +421,6 @@ struct gfs2_tune {
 	unsigned int gt_quota_quantum; /* Secs between syncs to quota file */
 	unsigned int gt_atime_quantum; /* Min secs between atime updates */
 	unsigned int gt_new_files_jdata;
-	unsigned int gt_new_files_directio;
 	unsigned int gt_max_readahead; /* Max bytes to read-ahead from disk */
 	unsigned int gt_stall_secs; /* Detects trouble! */
 	unsigned int gt_complain_secs;
@@ -534,7 +527,6 @@ struct gfs2_sbd {
 	struct mutex sd_rindex_mutex;
 	struct list_head sd_rindex_list;
 	struct list_head sd_rindex_mru_list;
-	struct list_head sd_rindex_recent_list;
 	struct gfs2_rgrpd *sd_rindex_forward;
 	unsigned int sd_rgrps;
 
diff --git a/fs/gfs2/inode.c b/fs/gfs2/inode.c
index 09453d057e4..6da0ab355b8 100644
--- a/fs/gfs2/inode.c
+++ b/fs/gfs2/inode.c
@@ -504,7 +504,7 @@ struct inode *gfs2_lookupi(struct inode *dir, const struct qstr *name,
 	}
 
 	if (!is_root) {
-		error = permission(dir, MAY_EXEC, NULL);
+		error = gfs2_permission(dir, MAY_EXEC);
 		if (error)
 			goto out;
 	}
@@ -667,7 +667,7 @@ static int create_ok(struct gfs2_inode *dip, const struct qstr *name,
 {
 	int error;
 
-	error = permission(&dip->i_inode, MAY_WRITE | MAY_EXEC, NULL);
+	error = gfs2_permission(&dip->i_inode, MAY_WRITE | MAY_EXEC);
 	if (error)
 		return error;
 
@@ -789,13 +789,8 @@ static void init_dinode(struct gfs2_inode *dip, struct gfs2_glock *gl,
 		if ((dip->i_di.di_flags & GFS2_DIF_INHERIT_JDATA) ||
 		    gfs2_tune_get(sdp, gt_new_files_jdata))
 			di->di_flags |= cpu_to_be32(GFS2_DIF_JDATA);
-		if ((dip->i_di.di_flags & GFS2_DIF_INHERIT_DIRECTIO) ||
-		    gfs2_tune_get(sdp, gt_new_files_directio))
-			di->di_flags |= cpu_to_be32(GFS2_DIF_DIRECTIO);
 	} else if (S_ISDIR(mode)) {
 		di->di_flags |= cpu_to_be32(dip->i_di.di_flags &
-					    GFS2_DIF_INHERIT_DIRECTIO);
-		di->di_flags |= cpu_to_be32(dip->i_di.di_flags &
 					    GFS2_DIF_INHERIT_JDATA);
 	}
 
@@ -1134,7 +1129,7 @@ int gfs2_unlink_ok(struct gfs2_inode *dip, const struct qstr *name,
 	if (IS_APPEND(&dip->i_inode))
 		return -EPERM;
 
-	error = permission(&dip->i_inode, MAY_WRITE | MAY_EXEC, NULL);
+	error = gfs2_permission(&dip->i_inode, MAY_WRITE | MAY_EXEC);
 	if (error)
 		return error;
 
diff --git a/fs/gfs2/inode.h b/fs/gfs2/inode.h
index 580da454b38..6074c2506f7 100644
--- a/fs/gfs2/inode.h
+++ b/fs/gfs2/inode.h
@@ -72,7 +72,6 @@ static inline void gfs2_inum_out(const struct gfs2_inode *ip,
 }
 
 
-void gfs2_inode_attr_in(struct gfs2_inode *ip);
 void gfs2_set_iop(struct inode *inode);
 struct inode *gfs2_inode_lookup(struct super_block *sb, unsigned type, 
 				u64 no_addr, u64 no_formal_ino,
@@ -91,6 +90,7 @@ int gfs2_rmdiri(struct gfs2_inode *dip, const struct qstr *name,
 		struct gfs2_inode *ip);
 int gfs2_unlink_ok(struct gfs2_inode *dip, const struct qstr *name,
 		   const struct gfs2_inode *ip);
+int gfs2_permission(struct inode *inode, int mask);
 int gfs2_ok_to_move(struct gfs2_inode *this, struct gfs2_inode *to);
 int gfs2_readlinki(struct gfs2_inode *ip, char **buf, unsigned int *len);
 int gfs2_glock_nq_atime(struct gfs2_holder *gh);
diff --git a/fs/gfs2/locking.c b/fs/gfs2/locking.c
index 663fee72878..523243a13a2 100644
--- a/fs/gfs2/locking.c
+++ b/fs/gfs2/locking.c
@@ -23,12 +23,54 @@ struct lmh_wrapper {
 	const struct lm_lockops *lw_ops;
 };
 
+static int nolock_mount(char *table_name, char *host_data,
+			lm_callback_t cb, void *cb_data,
+			unsigned int min_lvb_size, int flags,
+			struct lm_lockstruct *lockstruct,
+			struct kobject *fskobj);
+
 /* List of registered low-level locking protocols.  A file system selects one
    of them by name at mount time, e.g. lock_nolock, lock_dlm. */
 
+static const struct lm_lockops nolock_ops = {
+	.lm_proto_name = "lock_nolock",
+	.lm_mount = nolock_mount,
+};
+
+static struct lmh_wrapper nolock_proto  = {
+	.lw_list = LIST_HEAD_INIT(nolock_proto.lw_list),
+	.lw_ops = &nolock_ops,
+};
+
 static LIST_HEAD(lmh_list);
 static DEFINE_MUTEX(lmh_lock);
 
+static int nolock_mount(char *table_name, char *host_data,
+			lm_callback_t cb, void *cb_data,
+			unsigned int min_lvb_size, int flags,
+			struct lm_lockstruct *lockstruct,
+			struct kobject *fskobj)
+{
+	char *c;
+	unsigned int jid;
+
+	c = strstr(host_data, "jid=");
+	if (!c)
+		jid = 0;
+	else {
+		c += 4;
+		sscanf(c, "%u", &jid);
+	}
+
+	lockstruct->ls_jid = jid;
+	lockstruct->ls_first = 1;
+	lockstruct->ls_lvb_size = min_lvb_size;
+	lockstruct->ls_ops = &nolock_ops;
+	lockstruct->ls_flags = LM_LSFLAG_LOCAL;
+
+	return 0;
+}
+
 /**
  * gfs2_register_lockproto - Register a low-level locking protocol
  * @proto: the protocol definition
@@ -116,9 +158,13 @@ int gfs2_mount_lockproto(char *proto_name, char *table_name, char *host_data,
 	int try = 0;
 	int error, found;
 
+
 retry:
 	mutex_lock(&lmh_lock);
 
+	if (list_empty(&nolock_proto.lw_list))
+		list_add(&nolock_proto.lw_list, &lmh_list);
+
 	found = 0;
 	list_for_each_entry(lw, &lmh_list, lw_list) {
 		if (!strcmp(lw->lw_ops->lm_proto_name, proto_name)) {
@@ -139,7 +185,8 @@ retry:
 		goto out;
 	}
 
-	if (!try_module_get(lw->lw_ops->lm_owner)) {
+	if (lw->lw_ops->lm_owner &&
+	    !try_module_get(lw->lw_ops->lm_owner)) {
 		try = 0;
 		mutex_unlock(&lmh_lock);
 		msleep(1000);
@@ -158,7 +205,8 @@ out:
 void gfs2_unmount_lockproto(struct lm_lockstruct *lockstruct)
 {
 	mutex_lock(&lmh_lock);
-	lockstruct->ls_ops->lm_unmount(lockstruct->ls_lockspace);
+	if (lockstruct->ls_ops->lm_unmount)
+		lockstruct->ls_ops->lm_unmount(lockstruct->ls_lockspace);
 	if (lockstruct->ls_ops->lm_owner)
 		module_put(lockstruct->ls_ops->lm_owner);
 	mutex_unlock(&lmh_lock);
diff --git a/fs/gfs2/locking/dlm/lock.c b/fs/gfs2/locking/dlm/lock.c
index cf7ea8abec8..2482c904750 100644
--- a/fs/gfs2/locking/dlm/lock.c
+++ b/fs/gfs2/locking/dlm/lock.c
@@ -11,46 +11,60 @@
 
 static char junk_lvb[GDLM_LVB_SIZE];
 
-static void queue_complete(struct gdlm_lock *lp)
+
+/* convert dlm lock-mode to gfs lock-state */
+
+static s16 gdlm_make_lmstate(s16 dlmmode)
 {
-	struct gdlm_ls *ls = lp->ls;
+	switch (dlmmode) {
+	case DLM_LOCK_IV:
+	case DLM_LOCK_NL:
+		return LM_ST_UNLOCKED;
+	case DLM_LOCK_EX:
+		return LM_ST_EXCLUSIVE;
+	case DLM_LOCK_CW:
+		return LM_ST_DEFERRED;
+	case DLM_LOCK_PR:
+		return LM_ST_SHARED;
+	}
+	gdlm_assert(0, "unknown DLM mode %d", dlmmode);
+	return -1;
+}
 
-	clear_bit(LFL_ACTIVE, &lp->flags);
+/* A lock placed on this queue is re-submitted to DLM as soon as the lock_dlm
+   thread gets to it. */
+
+static void queue_submit(struct gdlm_lock *lp)
+{
+	struct gdlm_ls *ls = lp->ls;
 
 	spin_lock(&ls->async_lock);
-	list_add_tail(&lp->clist, &ls->complete);
+	list_add_tail(&lp->delay_list, &ls->submit);
 	spin_unlock(&ls->async_lock);
 	wake_up(&ls->thread_wait);
 }
 
-static inline void gdlm_ast(void *astarg)
+static void wake_up_ast(struct gdlm_lock *lp)
 {
-	queue_complete(astarg);
+	clear_bit(LFL_AST_WAIT, &lp->flags);
+	smp_mb__after_clear_bit();
+	wake_up_bit(&lp->flags, LFL_AST_WAIT);
 }
 
-static inline void gdlm_bast(void *astarg, int mode)
+static void gdlm_delete_lp(struct gdlm_lock *lp)
 {
-	struct gdlm_lock *lp = astarg;
 	struct gdlm_ls *ls = lp->ls;
 
-	if (!mode) {
-		printk(KERN_INFO "lock_dlm: bast mode zero %x,%llx\n",
-			lp->lockname.ln_type,
-			(unsigned long long)lp->lockname.ln_number);
-		return;
-	}
-
 	spin_lock(&ls->async_lock);
-	if (!lp->bast_mode) {
-		list_add_tail(&lp->blist, &ls->blocking);
-		lp->bast_mode = mode;
-	} else if (lp->bast_mode < mode)
-		lp->bast_mode = mode;
+	if (!list_empty(&lp->delay_list))
+		list_del_init(&lp->delay_list);
+	ls->all_locks_count--;
 	spin_unlock(&ls->async_lock);
-	wake_up(&ls->thread_wait);
+
+	kfree(lp);
 }
 
-void gdlm_queue_delayed(struct gdlm_lock *lp)
+static void gdlm_queue_delayed(struct gdlm_lock *lp)
 {
 	struct gdlm_ls *ls = lp->ls;
 
@@ -59,6 +73,236 @@ void gdlm_queue_delayed(struct gdlm_lock *lp)
 	spin_unlock(&ls->async_lock);
 }
 
+static void process_complete(struct gdlm_lock *lp)
+{
+	struct gdlm_ls *ls = lp->ls;
+	struct lm_async_cb acb;
+
+	memset(&acb, 0, sizeof(acb));
+
+	if (lp->lksb.sb_status == -DLM_ECANCEL) {
+		log_info("complete dlm cancel %x,%llx flags %lx",
+		 	 lp->lockname.ln_type,
+			 (unsigned long long)lp->lockname.ln_number,
+			 lp->flags);
+
+		lp->req = lp->cur;
+		acb.lc_ret |= LM_OUT_CANCELED;
+		if (lp->cur == DLM_LOCK_IV)
+			lp->lksb.sb_lkid = 0;
+		goto out;
+	}
+
+	if (test_and_clear_bit(LFL_DLM_UNLOCK, &lp->flags)) {
+		if (lp->lksb.sb_status != -DLM_EUNLOCK) {
+			log_info("unlock sb_status %d %x,%llx flags %lx",
+				 lp->lksb.sb_status, lp->lockname.ln_type,
+				 (unsigned long long)lp->lockname.ln_number,
+				 lp->flags);
+			return;
+		}
+
+		lp->cur = DLM_LOCK_IV;
+		lp->req = DLM_LOCK_IV;
+		lp->lksb.sb_lkid = 0;
+
+		if (test_and_clear_bit(LFL_UNLOCK_DELETE, &lp->flags)) {
+			gdlm_delete_lp(lp);
+			return;
+		}
+		goto out;
+	}
+
+	if (lp->lksb.sb_flags & DLM_SBF_VALNOTVALID)
+		memset(lp->lksb.sb_lvbptr, 0, GDLM_LVB_SIZE);
+
+	if (lp->lksb.sb_flags & DLM_SBF_ALTMODE) {
+		if (lp->req == DLM_LOCK_PR)
+			lp->req = DLM_LOCK_CW;
+		else if (lp->req == DLM_LOCK_CW)
+			lp->req = DLM_LOCK_PR;
+	}
+
+	/*
+	 * A canceled lock request.  The lock was just taken off the delayed
+	 * list and was never even submitted to dlm.
+	 */
+
+	if (test_and_clear_bit(LFL_CANCEL, &lp->flags)) {
+		log_info("complete internal cancel %x,%llx",
+		 	 lp->lockname.ln_type,
+			 (unsigned long long)lp->lockname.ln_number);
+		lp->req = lp->cur;
+		acb.lc_ret |= LM_OUT_CANCELED;
+		goto out;
+	}
+
+	/*
+	 * An error occured.
+	 */
+
+	if (lp->lksb.sb_status) {
+		/* a "normal" error */
+		if ((lp->lksb.sb_status == -EAGAIN) &&
+		    (lp->lkf & DLM_LKF_NOQUEUE)) {
+			lp->req = lp->cur;
+			if (lp->cur == DLM_LOCK_IV)
+				lp->lksb.sb_lkid = 0;
+			goto out;
+		}
+
+		/* this could only happen with cancels I think */
+		log_info("ast sb_status %d %x,%llx flags %lx",
+			 lp->lksb.sb_status, lp->lockname.ln_type,
+			 (unsigned long long)lp->lockname.ln_number,
+			 lp->flags);
+		return;
+	}
+
+	/*
+	 * This is an AST for an EX->EX conversion for sync_lvb from GFS.
+	 */
+
+	if (test_and_clear_bit(LFL_SYNC_LVB, &lp->flags)) {
+		wake_up_ast(lp);
+		return;
+	}
+
+	/*
+	 * A lock has been demoted to NL because it initially completed during
+	 * BLOCK_LOCKS.  Now it must be requested in the originally requested
+	 * mode.
+	 */
+
+	if (test_and_clear_bit(LFL_REREQUEST, &lp->flags)) {
+		gdlm_assert(lp->req == DLM_LOCK_NL, "%x,%llx",
+			    lp->lockname.ln_type,
+			    (unsigned long long)lp->lockname.ln_number);
+		gdlm_assert(lp->prev_req > DLM_LOCK_NL, "%x,%llx",
+			    lp->lockname.ln_type,
+			    (unsigned long long)lp->lockname.ln_number);
+
+		lp->cur = DLM_LOCK_NL;
+		lp->req = lp->prev_req;
+		lp->prev_req = DLM_LOCK_IV;
+		lp->lkf &= ~DLM_LKF_CONVDEADLK;
+
+		set_bit(LFL_NOCACHE, &lp->flags);
+
+		if (test_bit(DFL_BLOCK_LOCKS, &ls->flags) &&
+		    !test_bit(LFL_NOBLOCK, &lp->flags))
+			gdlm_queue_delayed(lp);
+		else
+			queue_submit(lp);
+		return;
+	}
+
+	/*
+	 * A request is granted during dlm recovery.  It may be granted
+	 * because the locks of a failed node were cleared.  In that case,
+	 * there may be inconsistent data beneath this lock and we must wait
+	 * for recovery to complete to use it.  When gfs recovery is done this
+	 * granted lock will be converted to NL and then reacquired in this
+	 * granted state.
+	 */
+
+	if (test_bit(DFL_BLOCK_LOCKS, &ls->flags) &&
+	    !test_bit(LFL_NOBLOCK, &lp->flags) &&
+	    lp->req != DLM_LOCK_NL) {
+
+		lp->cur = lp->req;
+		lp->prev_req = lp->req;
+		lp->req = DLM_LOCK_NL;
+		lp->lkf |= DLM_LKF_CONVERT;
+		lp->lkf &= ~DLM_LKF_CONVDEADLK;
+
+		log_debug("rereq %x,%llx id %x %d,%d",
+			  lp->lockname.ln_type,
+			  (unsigned long long)lp->lockname.ln_number,
+			  lp->lksb.sb_lkid, lp->cur, lp->req);
+
+		set_bit(LFL_REREQUEST, &lp->flags);
+		queue_submit(lp);
+		return;
+	}
+
+	/*
+	 * DLM demoted the lock to NL before it was granted so GFS must be
+	 * told it cannot cache data for this lock.
+	 */
+
+	if (lp->lksb.sb_flags & DLM_SBF_DEMOTED)
+		set_bit(LFL_NOCACHE, &lp->flags);
+
+out:
+	/*
+	 * This is an internal lock_dlm lock
+	 */
+
+	if (test_bit(LFL_INLOCK, &lp->flags)) {
+		clear_bit(LFL_NOBLOCK, &lp->flags);
+		lp->cur = lp->req;
+		wake_up_ast(lp);
+		return;
+	}
+
+	/*
+	 * Normal completion of a lock request.  Tell GFS it now has the lock.
+	 */
+
+	clear_bit(LFL_NOBLOCK, &lp->flags);
+	lp->cur = lp->req;
+
+	acb.lc_name = lp->lockname;
+	acb.lc_ret |= gdlm_make_lmstate(lp->cur);
+
+	ls->fscb(ls->sdp, LM_CB_ASYNC, &acb);
+}
+
+static void gdlm_ast(void *astarg)
+{
+	struct gdlm_lock *lp = astarg;
+	clear_bit(LFL_ACTIVE, &lp->flags);
+	process_complete(lp);
+}
+
+static void process_blocking(struct gdlm_lock *lp, int bast_mode)
+{
+	struct gdlm_ls *ls = lp->ls;
+	unsigned int cb = 0;
+
+	switch (gdlm_make_lmstate(bast_mode)) {
+	case LM_ST_EXCLUSIVE:
+		cb = LM_CB_NEED_E;
+		break;
+	case LM_ST_DEFERRED:
+		cb = LM_CB_NEED_D;
+		break;
+	case LM_ST_SHARED:
+		cb = LM_CB_NEED_S;
+		break;
+	default:
+		gdlm_assert(0, "unknown bast mode %u", bast_mode);
+	}
+
+	ls->fscb(ls->sdp, cb, &lp->lockname);
+}
+
+
+static void gdlm_bast(void *astarg, int mode)
+{
+	struct gdlm_lock *lp = astarg;
+
+	if (!mode) {
+		printk(KERN_INFO "lock_dlm: bast mode zero %x,%llx\n",
+			lp->lockname.ln_type,
+			(unsigned long long)lp->lockname.ln_number);
+		return;
+	}
+
+	process_blocking(lp, mode);
+}
+
 /* convert gfs lock-state to dlm lock-mode */
 
 static s16 make_mode(s16 lmstate)
@@ -77,24 +321,6 @@ static s16 make_mode(s16 lmstate)
 	return -1;
 }
 
-/* convert dlm lock-mode to gfs lock-state */
-
-s16 gdlm_make_lmstate(s16 dlmmode)
-{
-	switch (dlmmode) {
-	case DLM_LOCK_IV:
-	case DLM_LOCK_NL:
-		return LM_ST_UNLOCKED;
-	case DLM_LOCK_EX:
-		return LM_ST_EXCLUSIVE;
-	case DLM_LOCK_CW:
-		return LM_ST_DEFERRED;
-	case DLM_LOCK_PR:
-		return LM_ST_SHARED;
-	}
-	gdlm_assert(0, "unknown DLM mode %d", dlmmode);
-	return -1;
-}
 
 /* verify agreement with GFS on the current lock state, NB: DLM_LOCK_NL and
    DLM_LOCK_IV are both considered LM_ST_UNLOCKED by GFS. */
@@ -134,14 +360,6 @@ static inline unsigned int make_flags(struct gdlm_lock *lp,
 
 	if (lp->lksb.sb_lkid != 0) {
 		lkf |= DLM_LKF_CONVERT;
-
-		/* Conversion deadlock avoidance by DLM */
-
-		if (!(lp->ls->fsflags & LM_MFLAG_CONV_NODROP) &&
-		    !test_bit(LFL_FORCE_PROMOTE, &lp->flags) &&
-		    !(lkf & DLM_LKF_NOQUEUE) &&
-		    cur > DLM_LOCK_NL && req > DLM_LOCK_NL && cur != req)
-			lkf |= DLM_LKF_CONVDEADLK;
 	}
 
 	if (lp->lvb)
@@ -173,14 +391,9 @@ static int gdlm_create_lp(struct gdlm_ls *ls, struct lm_lockname *name,
 	make_strname(name, &lp->strname);
 	lp->ls = ls;
 	lp->cur = DLM_LOCK_IV;
-	lp->lvb = NULL;
-	lp->hold_null = NULL;
-	INIT_LIST_HEAD(&lp->clist);
-	INIT_LIST_HEAD(&lp->blist);
 	INIT_LIST_HEAD(&lp->delay_list);
 
 	spin_lock(&ls->async_lock);
-	list_add(&lp->all_list, &ls->all_locks);
 	ls->all_locks_count++;
 	spin_unlock(&ls->async_lock);
 
@@ -188,26 +401,6 @@ static int gdlm_create_lp(struct gdlm_ls *ls, struct lm_lockname *name,
 	return 0;
 }
 
-void gdlm_delete_lp(struct gdlm_lock *lp)
-{
-	struct gdlm_ls *ls = lp->ls;
-
-	spin_lock(&ls->async_lock);
-	if (!list_empty(&lp->clist))
-		list_del_init(&lp->clist);
-	if (!list_empty(&lp->blist))
-		list_del_init(&lp->blist);
-	if (!list_empty(&lp->delay_list))
-		list_del_init(&lp->delay_list);
-	gdlm_assert(!list_empty(&lp->all_list), "%x,%llx", lp->lockname.ln_type,
-		    (unsigned long long)lp->lockname.ln_number);
-	list_del_init(&lp->all_list);
-	ls->all_locks_count--;
-	spin_unlock(&ls->async_lock);
-
-	kfree(lp);
-}
-
 int gdlm_get_lock(void *lockspace, struct lm_lockname *name,
 		  void **lockp)
 {
@@ -261,7 +454,7 @@ unsigned int gdlm_do_lock(struct gdlm_lock *lp)
 
 	if ((error == -EAGAIN) && (lp->lkf & DLM_LKF_NOQUEUE)) {
 		lp->lksb.sb_status = -EAGAIN;
-		queue_complete(lp);
+		gdlm_ast(lp);
 		error = 0;
 	}
 
@@ -308,6 +501,12 @@ unsigned int gdlm_lock(void *lock, unsigned int cur_state,
 {
 	struct gdlm_lock *lp = lock;
 
+	if (req_state == LM_ST_UNLOCKED)
+		return gdlm_unlock(lock, cur_state);
+
+	if (req_state == LM_ST_UNLOCKED)
+		return gdlm_unlock(lock, cur_state);
+
 	clear_bit(LFL_DLM_CANCEL, &lp->flags);
 	if (flags & LM_FLAG_NOEXP)
 		set_bit(LFL_NOBLOCK, &lp->flags);
@@ -351,7 +550,7 @@ void gdlm_cancel(void *lock)
 	if (delay_list) {
 		set_bit(LFL_CANCEL, &lp->flags);
 		set_bit(LFL_ACTIVE, &lp->flags);
-		queue_complete(lp);
+		gdlm_ast(lp);
 		return;
 	}
 
@@ -507,22 +706,3 @@ void gdlm_submit_delayed(struct gdlm_ls *ls)
 	wake_up(&ls->thread_wait);
 }
 
-int gdlm_release_all_locks(struct gdlm_ls *ls)
-{
-	struct gdlm_lock *lp, *safe;
-	int count = 0;
-
-	spin_lock(&ls->async_lock);
-	list_for_each_entry_safe(lp, safe, &ls->all_locks, all_list) {
-		list_del_init(&lp->all_list);
-
-		if (lp->lvb && lp->lvb != junk_lvb)
-			kfree(lp->lvb);
-		kfree(lp);
-		count++;
-	}
-	spin_unlock(&ls->async_lock);
-
-	return count;
-}
-
diff --git a/fs/gfs2/locking/dlm/lock_dlm.h b/fs/gfs2/locking/dlm/lock_dlm.h
index a243cf69c54..3c98e7c6f93 100644
--- a/fs/gfs2/locking/dlm/lock_dlm.h
+++ b/fs/gfs2/locking/dlm/lock_dlm.h
@@ -72,19 +72,12 @@ struct gdlm_ls {
 	int			recover_jid_done;
 	int			recover_jid_status;
 	spinlock_t		async_lock;
-	struct list_head	complete;
-	struct list_head	blocking;
 	struct list_head	delayed;
 	struct list_head	submit;
-	struct list_head	all_locks;
 	u32		all_locks_count;
 	wait_queue_head_t	wait_control;
-	struct task_struct	*thread1;
-	struct task_struct	*thread2;
+	struct task_struct	*thread;
 	wait_queue_head_t	thread_wait;
-	unsigned long		drop_time;
-	int			drop_locks_count;
-	int			drop_locks_period;
 };
 
 enum {
@@ -117,12 +110,7 @@ struct gdlm_lock {
 	u32			lkf;		/* dlm flags DLM_LKF_ */
 	unsigned long		flags;		/* lock_dlm flags LFL_ */
 
-	int			bast_mode;	/* protected by async_lock */
-
-	struct list_head	clist;		/* complete */
-	struct list_head	blist;		/* blocking */
 	struct list_head	delay_list;	/* delayed */
-	struct list_head	all_list;	/* all locks for the fs */
 	struct gdlm_lock	*hold_null;	/* NL lock for hold_lvb */
 };
 
@@ -159,11 +147,7 @@ void gdlm_release_threads(struct gdlm_ls *);
 
 /* lock.c */
 
-s16 gdlm_make_lmstate(s16);
-void gdlm_queue_delayed(struct gdlm_lock *);
 void gdlm_submit_delayed(struct gdlm_ls *);
-int gdlm_release_all_locks(struct gdlm_ls *);
-void gdlm_delete_lp(struct gdlm_lock *);
 unsigned int gdlm_do_lock(struct gdlm_lock *);
 
 int gdlm_get_lock(void *, struct lm_lockname *, void **);
diff --git a/fs/gfs2/locking/dlm/mount.c b/fs/gfs2/locking/dlm/mount.c
index 470bdf650b5..09d78c216f4 100644
--- a/fs/gfs2/locking/dlm/mount.c
+++ b/fs/gfs2/locking/dlm/mount.c
@@ -22,22 +22,14 @@ static struct gdlm_ls *init_gdlm(lm_callback_t cb, struct gfs2_sbd *sdp,
 	if (!ls)
 		return NULL;
 
-	ls->drop_locks_count = GDLM_DROP_COUNT;
-	ls->drop_locks_period = GDLM_DROP_PERIOD;
 	ls->fscb = cb;
 	ls->sdp = sdp;
 	ls->fsflags = flags;
 	spin_lock_init(&ls->async_lock);
-	INIT_LIST_HEAD(&ls->complete);
-	INIT_LIST_HEAD(&ls->blocking);
 	INIT_LIST_HEAD(&ls->delayed);
 	INIT_LIST_HEAD(&ls->submit);
-	INIT_LIST_HEAD(&ls->all_locks);
 	init_waitqueue_head(&ls->thread_wait);
 	init_waitqueue_head(&ls->wait_control);
-	ls->thread1 = NULL;
-	ls->thread2 = NULL;
-	ls->drop_time = jiffies;
 	ls->jid = -1;
 
 	strncpy(buf, table_name, 256);
@@ -180,7 +172,6 @@ out:
 static void gdlm_unmount(void *lockspace)
 {
 	struct gdlm_ls *ls = lockspace;
-	int rv;
 
 	log_debug("unmount flags %lx", ls->flags);
 
@@ -194,9 +185,7 @@ static void gdlm_unmount(void *lockspace)
 	gdlm_kobject_release(ls);
 	dlm_release_lockspace(ls->dlm_lockspace, 2);
 	gdlm_release_threads(ls);
-	rv = gdlm_release_all_locks(ls);
-	if (rv)
-		log_info("gdlm_unmount: %d stray locks freed", rv);
+	BUG_ON(ls->all_locks_count);
 out:
 	kfree(ls);
 }
@@ -232,7 +221,6 @@ static void gdlm_withdraw(void *lockspace)
 
 	dlm_release_lockspace(ls->dlm_lockspace, 2);
 	gdlm_release_threads(ls);
-	gdlm_release_all_locks(ls);
 	gdlm_kobject_release(ls);
 }
 
diff --git a/fs/gfs2/locking/dlm/sysfs.c b/fs/gfs2/locking/dlm/sysfs.c
index a4ff271df9e..4ec571c3d8a 100644
--- a/fs/gfs2/locking/dlm/sysfs.c
+++ b/fs/gfs2/locking/dlm/sysfs.c
@@ -114,17 +114,6 @@ static ssize_t recover_status_show(struct gdlm_ls *ls, char *buf)
 	return sprintf(buf, "%d\n", ls->recover_jid_status);
 }
 
-static ssize_t drop_count_show(struct gdlm_ls *ls, char *buf)
-{
-	return sprintf(buf, "%d\n", ls->drop_locks_count);
-}
-
-static ssize_t drop_count_store(struct gdlm_ls *ls, const char *buf, size_t len)
-{
-	ls->drop_locks_count = simple_strtol(buf, NULL, 0);
-	return len;
-}
-
 struct gdlm_attr {
 	struct attribute attr;
 	ssize_t (*show)(struct gdlm_ls *, char *);
@@ -144,7 +133,6 @@ GDLM_ATTR(first_done,     0444, first_done_show,     NULL);
 GDLM_ATTR(recover,        0644, recover_show,        recover_store);
 GDLM_ATTR(recover_done,   0444, recover_done_show,   NULL);
 GDLM_ATTR(recover_status, 0444, recover_status_show, NULL);
-GDLM_ATTR(drop_count,     0644, drop_count_show,     drop_count_store);
 
 static struct attribute *gdlm_attrs[] = {
 	&gdlm_attr_proto_name.attr,
@@ -157,7 +145,6 @@ static struct attribute *gdlm_attrs[] = {
 	&gdlm_attr_recover.attr,
 	&gdlm_attr_recover_done.attr,
 	&gdlm_attr_recover_status.attr,
-	&gdlm_attr_drop_count.attr,
 	NULL,
 };
 
diff --git a/fs/gfs2/locking/dlm/thread.c b/fs/gfs2/locking/dlm/thread.c
index e53db6fd28a..38823efd698 100644
--- a/fs/gfs2/locking/dlm/thread.c
+++ b/fs/gfs2/locking/dlm/thread.c
@@ -9,367 +9,60 @@
 
 #include "lock_dlm.h"
 
-/* A lock placed on this queue is re-submitted to DLM as soon as the lock_dlm
-   thread gets to it. */
-
-static void queue_submit(struct gdlm_lock *lp)
-{
-	struct gdlm_ls *ls = lp->ls;
-
-	spin_lock(&ls->async_lock);
-	list_add_tail(&lp->delay_list, &ls->submit);
-	spin_unlock(&ls->async_lock);
-	wake_up(&ls->thread_wait);
-}
-
-static void process_blocking(struct gdlm_lock *lp, int bast_mode)
-{
-	struct gdlm_ls *ls = lp->ls;
-	unsigned int cb = 0;
-
-	switch (gdlm_make_lmstate(bast_mode)) {
-	case LM_ST_EXCLUSIVE:
-		cb = LM_CB_NEED_E;
-		break;
-	case LM_ST_DEFERRED:
-		cb = LM_CB_NEED_D;
-		break;
-	case LM_ST_SHARED:
-		cb = LM_CB_NEED_S;
-		break;
-	default:
-		gdlm_assert(0, "unknown bast mode %u", lp->bast_mode);
-	}
-
-	ls->fscb(ls->sdp, cb, &lp->lockname);
-}
-
-static void wake_up_ast(struct gdlm_lock *lp)
-{
-	clear_bit(LFL_AST_WAIT, &lp->flags);
-	smp_mb__after_clear_bit();
-	wake_up_bit(&lp->flags, LFL_AST_WAIT);
-}
-
-static void process_complete(struct gdlm_lock *lp)
-{
-	struct gdlm_ls *ls = lp->ls;
-	struct lm_async_cb acb;
-	s16 prev_mode = lp->cur;
-
-	memset(&acb, 0, sizeof(acb));
-
-	if (lp->lksb.sb_status == -DLM_ECANCEL) {
-		log_info("complete dlm cancel %x,%llx flags %lx",
-		 	 lp->lockname.ln_type,
-			 (unsigned long long)lp->lockname.ln_number,
-			 lp->flags);
-
-		lp->req = lp->cur;
-		acb.lc_ret |= LM_OUT_CANCELED;
-		if (lp->cur == DLM_LOCK_IV)
-			lp->lksb.sb_lkid = 0;
-		goto out;
-	}
-
-	if (test_and_clear_bit(LFL_DLM_UNLOCK, &lp->flags)) {
-		if (lp->lksb.sb_status != -DLM_EUNLOCK) {
-			log_info("unlock sb_status %d %x,%llx flags %lx",
-				 lp->lksb.sb_status, lp->lockname.ln_type,
-				 (unsigned long long)lp->lockname.ln_number,
-				 lp->flags);
-			return;
-		}
-
-		lp->cur = DLM_LOCK_IV;
-		lp->req = DLM_LOCK_IV;
-		lp->lksb.sb_lkid = 0;
-
-		if (test_and_clear_bit(LFL_UNLOCK_DELETE, &lp->flags)) {
-			gdlm_delete_lp(lp);
-			return;
-		}
-		goto out;
-	}
-
-	if (lp->lksb.sb_flags & DLM_SBF_VALNOTVALID)
-		memset(lp->lksb.sb_lvbptr, 0, GDLM_LVB_SIZE);
-
-	if (lp->lksb.sb_flags & DLM_SBF_ALTMODE) {
-		if (lp->req == DLM_LOCK_PR)
-			lp->req = DLM_LOCK_CW;
-		else if (lp->req == DLM_LOCK_CW)
-			lp->req = DLM_LOCK_PR;
-	}
-
-	/*
-	 * A canceled lock request.  The lock was just taken off the delayed
-	 * list and was never even submitted to dlm.
-	 */
-
-	if (test_and_clear_bit(LFL_CANCEL, &lp->flags)) {
-		log_info("complete internal cancel %x,%llx",
-		 	 lp->lockname.ln_type,
-			 (unsigned long long)lp->lockname.ln_number);
-		lp->req = lp->cur;
-		acb.lc_ret |= LM_OUT_CANCELED;
-		goto out;
-	}
-
-	/*
-	 * An error occured.
-	 */
-
-	if (lp->lksb.sb_status) {
-		/* a "normal" error */
-		if ((lp->lksb.sb_status == -EAGAIN) &&
-		    (lp->lkf & DLM_LKF_NOQUEUE)) {
-			lp->req = lp->cur;
-			if (lp->cur == DLM_LOCK_IV)
-				lp->lksb.sb_lkid = 0;
-			goto out;
-		}
-
-		/* this could only happen with cancels I think */
-		log_info("ast sb_status %d %x,%llx flags %lx",
-			 lp->lksb.sb_status, lp->lockname.ln_type,
-			 (unsigned long long)lp->lockname.ln_number,
-			 lp->flags);
-		if (lp->lksb.sb_status == -EDEADLOCK &&
-		    lp->ls->fsflags & LM_MFLAG_CONV_NODROP) {
-			lp->req = lp->cur;
-			acb.lc_ret |= LM_OUT_CONV_DEADLK;
-			if (lp->cur == DLM_LOCK_IV)
-				lp->lksb.sb_lkid = 0;
-			goto out;
-		} else
-			return;
-	}
-
-	/*
-	 * This is an AST for an EX->EX conversion for sync_lvb from GFS.
-	 */
-
-	if (test_and_clear_bit(LFL_SYNC_LVB, &lp->flags)) {
-		wake_up_ast(lp);
-		return;
-	}
-
-	/*
-	 * A lock has been demoted to NL because it initially completed during
-	 * BLOCK_LOCKS.  Now it must be requested in the originally requested
-	 * mode.
-	 */
-
-	if (test_and_clear_bit(LFL_REREQUEST, &lp->flags)) {
-		gdlm_assert(lp->req == DLM_LOCK_NL, "%x,%llx",
-			    lp->lockname.ln_type,
-			    (unsigned long long)lp->lockname.ln_number);
-		gdlm_assert(lp->prev_req > DLM_LOCK_NL, "%x,%llx",
-			    lp->lockname.ln_type,
-			    (unsigned long long)lp->lockname.ln_number);
-
-		lp->cur = DLM_LOCK_NL;
-		lp->req = lp->prev_req;
-		lp->prev_req = DLM_LOCK_IV;
-		lp->lkf &= ~DLM_LKF_CONVDEADLK;
-
-		set_bit(LFL_NOCACHE, &lp->flags);
-
-		if (test_bit(DFL_BLOCK_LOCKS, &ls->flags) &&
-		    !test_bit(LFL_NOBLOCK, &lp->flags))
-			gdlm_queue_delayed(lp);
-		else
-			queue_submit(lp);
-		return;
-	}
-
-	/*
-	 * A request is granted during dlm recovery.  It may be granted
-	 * because the locks of a failed node were cleared.  In that case,
-	 * there may be inconsistent data beneath this lock and we must wait
-	 * for recovery to complete to use it.  When gfs recovery is done this
-	 * granted lock will be converted to NL and then reacquired in this
-	 * granted state.
-	 */
-
-	if (test_bit(DFL_BLOCK_LOCKS, &ls->flags) &&
-	    !test_bit(LFL_NOBLOCK, &lp->flags) &&
-	    lp->req != DLM_LOCK_NL) {
-
-		lp->cur = lp->req;
-		lp->prev_req = lp->req;
-		lp->req = DLM_LOCK_NL;
-		lp->lkf |= DLM_LKF_CONVERT;
-		lp->lkf &= ~DLM_LKF_CONVDEADLK;
-
-		log_debug("rereq %x,%llx id %x %d,%d",
-			  lp->lockname.ln_type,
-			  (unsigned long long)lp->lockname.ln_number,
-			  lp->lksb.sb_lkid, lp->cur, lp->req);
-
-		set_bit(LFL_REREQUEST, &lp->flags);
-		queue_submit(lp);
-		return;
-	}
-
-	/*
-	 * DLM demoted the lock to NL before it was granted so GFS must be
-	 * told it cannot cache data for this lock.
-	 */
-
-	if (lp->lksb.sb_flags & DLM_SBF_DEMOTED)
-		set_bit(LFL_NOCACHE, &lp->flags);
-
-out:
-	/*
-	 * This is an internal lock_dlm lock
-	 */
-
-	if (test_bit(LFL_INLOCK, &lp->flags)) {
-		clear_bit(LFL_NOBLOCK, &lp->flags);
-		lp->cur = lp->req;
-		wake_up_ast(lp);
-		return;
-	}
-
-	/*
-	 * Normal completion of a lock request.  Tell GFS it now has the lock.
-	 */
-
-	clear_bit(LFL_NOBLOCK, &lp->flags);
-	lp->cur = lp->req;
-
-	acb.lc_name = lp->lockname;
-	acb.lc_ret |= gdlm_make_lmstate(lp->cur);
-
-	if (!test_and_clear_bit(LFL_NOCACHE, &lp->flags) &&
-	    (lp->cur > DLM_LOCK_NL) && (prev_mode > DLM_LOCK_NL))
-		acb.lc_ret |= LM_OUT_CACHEABLE;
-
-	ls->fscb(ls->sdp, LM_CB_ASYNC, &acb);
-}
-
-static inline int no_work(struct gdlm_ls *ls, int blocking)
+static inline int no_work(struct gdlm_ls *ls)
 {
 	int ret;
 
 	spin_lock(&ls->async_lock);
-	ret = list_empty(&ls->complete) && list_empty(&ls->submit);
-	if (ret && blocking)
-		ret = list_empty(&ls->blocking);
+	ret = list_empty(&ls->submit);
 	spin_unlock(&ls->async_lock);
 
 	return ret;
 }
 
-static inline int check_drop(struct gdlm_ls *ls)
-{
-	if (!ls->drop_locks_count)
-		return 0;
-
-	if (time_after(jiffies, ls->drop_time + ls->drop_locks_period * HZ)) {
-		ls->drop_time = jiffies;
-		if (ls->all_locks_count >= ls->drop_locks_count)
-			return 1;
-	}
-	return 0;
-}
-
-static int gdlm_thread(void *data, int blist)
+static int gdlm_thread(void *data)
 {
 	struct gdlm_ls *ls = (struct gdlm_ls *) data;
 	struct gdlm_lock *lp = NULL;
-	uint8_t complete, blocking, submit, drop;
-
-	/* Only thread1 is allowed to do blocking callbacks since gfs
-	   may wait for a completion callback within a blocking cb. */
 
 	while (!kthread_should_stop()) {
 		wait_event_interruptible(ls->thread_wait,
-				!no_work(ls, blist) || kthread_should_stop());
-
-		complete = blocking = submit = drop = 0;
+				!no_work(ls) || kthread_should_stop());
 
 		spin_lock(&ls->async_lock);
 
-		if (blist && !list_empty(&ls->blocking)) {
-			lp = list_entry(ls->blocking.next, struct gdlm_lock,
-					blist);
-			list_del_init(&lp->blist);
-			blocking = lp->bast_mode;
-			lp->bast_mode = 0;
-		} else if (!list_empty(&ls->complete)) {
-			lp = list_entry(ls->complete.next, struct gdlm_lock,
-					clist);
-			list_del_init(&lp->clist);
-			complete = 1;
-		} else if (!list_empty(&ls->submit)) {
+		if (!list_empty(&ls->submit)) {
 			lp = list_entry(ls->submit.next, struct gdlm_lock,
 					delay_list);
 			list_del_init(&lp->delay_list);
-			submit = 1;
+			spin_unlock(&ls->async_lock);
+			gdlm_do_lock(lp);
+			spin_lock(&ls->async_lock);
 		}
-
-		drop = check_drop(ls);
 		spin_unlock(&ls->async_lock);
-
-		if (complete)
-			process_complete(lp);
-
-		else if (blocking)
-			process_blocking(lp, blocking);
-
-		else if (submit)
-			gdlm_do_lock(lp);
-
-		if (drop)
-			ls->fscb(ls->sdp, LM_CB_DROPLOCKS, NULL);
-
-		schedule();
 	}
 
 	return 0;
 }
 
-static int gdlm_thread1(void *data)
-{
-	return gdlm_thread(data, 1);
-}
-
-static int gdlm_thread2(void *data)
-{
-	return gdlm_thread(data, 0);
-}
-
 int gdlm_init_threads(struct gdlm_ls *ls)
 {
 	struct task_struct *p;
 	int error;
 
-	p = kthread_run(gdlm_thread1, ls, "lock_dlm1");
-	error = IS_ERR(p);
-	if (error) {
-		log_error("can't start lock_dlm1 thread %d", error);
-		return error;
-	}
-	ls->thread1 = p;
-
-	p = kthread_run(gdlm_thread2, ls, "lock_dlm2");
+	p = kthread_run(gdlm_thread, ls, "lock_dlm");
 	error = IS_ERR(p);
 	if (error) {
-		log_error("can't start lock_dlm2 thread %d", error);
-		kthread_stop(ls->thread1);
+		log_error("can't start lock_dlm thread %d", error);
 		return error;
 	}
-	ls->thread2 = p;
+	ls->thread = p;
 
 	return 0;
 }
 
 void gdlm_release_threads(struct gdlm_ls *ls)
 {
-	kthread_stop(ls->thread1);
-	kthread_stop(ls->thread2);
+	kthread_stop(ls->thread);
 }
 
diff --git a/fs/gfs2/locking/nolock/Makefile b/fs/gfs2/locking/nolock/Makefile
deleted file mode 100644
index 35e9730bc3a..00000000000
--- a/fs/gfs2/locking/nolock/Makefile
+++ /dev/null
@@ -1,3 +0,0 @@
-obj-$(CONFIG_GFS2_FS_LOCKING_NOLOCK) += lock_nolock.o
-lock_nolock-y := main.o
-
diff --git a/fs/gfs2/locking/nolock/main.c b/fs/gfs2/locking/nolock/main.c
deleted file mode 100644
index 284a5ece8d9..00000000000
--- a/fs/gfs2/locking/nolock/main.c
+++ /dev/null
@@ -1,238 +0,0 @@
-/*
- * Copyright (C) Sistina Software, Inc.  1997-2003 All rights reserved.
- * Copyright (C) 2004-2005 Red Hat, Inc.  All rights reserved.
- *
- * This copyrighted material is made available to anyone wishing to use,
- * modify, copy, or redistribute it subject to the terms and conditions
- * of the GNU General Public License version 2.
- */
-
-#include <linux/module.h>
-#include <linux/slab.h>
-#include <linux/init.h>
-#include <linux/types.h>
-#include <linux/fs.h>
-#include <linux/lm_interface.h>
-
-struct nolock_lockspace {
-	unsigned int nl_lvb_size;
-};
-
-static const struct lm_lockops nolock_ops;
-
-static int nolock_mount(char *table_name, char *host_data,
-			lm_callback_t cb, void *cb_data,
-			unsigned int min_lvb_size, int flags,
-			struct lm_lockstruct *lockstruct,
-			struct kobject *fskobj)
-{
-	char *c;
-	unsigned int jid;
-	struct nolock_lockspace *nl;
-
-	c = strstr(host_data, "jid=");
-	if (!c)
-		jid = 0;
-	else {
-		c += 4;
-		sscanf(c, "%u", &jid);
-	}
-
-	nl = kzalloc(sizeof(struct nolock_lockspace), GFP_KERNEL);
-	if (!nl)
-		return -ENOMEM;
-
-	nl->nl_lvb_size = min_lvb_size;
-
-	lockstruct->ls_jid = jid;
-	lockstruct->ls_first = 1;
-	lockstruct->ls_lvb_size = min_lvb_size;
-	lockstruct->ls_lockspace = nl;
-	lockstruct->ls_ops = &nolock_ops;
-	lockstruct->ls_flags = LM_LSFLAG_LOCAL;
-
-	return 0;
-}
-
-static void nolock_others_may_mount(void *lockspace)
-{
-}
-
-static void nolock_unmount(void *lockspace)
-{
-	struct nolock_lockspace *nl = lockspace;
-	kfree(nl);
-}
-
-static void nolock_withdraw(void *lockspace)
-{
-}
-
-/**
- * nolock_get_lock - get a lm_lock_t given a descripton of the lock
- * @lockspace: the lockspace the lock lives in
- * @name: the name of the lock
- * @lockp: return the lm_lock_t here
- *
- * Returns: 0 on success, -EXXX on failure
- */
-
-static int nolock_get_lock(void *lockspace, struct lm_lockname *name,
-			   void **lockp)
-{
-	*lockp = lockspace;
-	return 0;
-}
-
-/**
- * nolock_put_lock - get rid of a lock structure
- * @lock: the lock to throw away
- *
- */
-
-static void nolock_put_lock(void *lock)
-{
-}
-
-/**
- * nolock_lock - acquire a lock
- * @lock: the lock to manipulate
- * @cur_state: the current state
- * @req_state: the requested state
- * @flags: modifier flags
- *
- * Returns: A bitmap of LM_OUT_*
- */
-
-static unsigned int nolock_lock(void *lock, unsigned int cur_state,
-				unsigned int req_state, unsigned int flags)
-{
-	return req_state | LM_OUT_CACHEABLE;
-}
-
-/**
- * nolock_unlock - unlock a lock
- * @lock: the lock to manipulate
- * @cur_state: the current state
- *
- * Returns: 0
- */
-
-static unsigned int nolock_unlock(void *lock, unsigned int cur_state)
-{
-	return 0;
-}
-
-static void nolock_cancel(void *lock)
-{
-}
-
-/**
- * nolock_hold_lvb - hold on to a lock value block
- * @lock: the lock the LVB is associated with
- * @lvbp: return the lm_lvb_t here
- *
- * Returns: 0 on success, -EXXX on failure
- */
-
-static int nolock_hold_lvb(void *lock, char **lvbp)
-{
-	struct nolock_lockspace *nl = lock;
-	int error = 0;
-
-	*lvbp = kzalloc(nl->nl_lvb_size, GFP_NOFS);
-	if (!*lvbp)
-		error = -ENOMEM;
-
-	return error;
-}
-
-/**
- * nolock_unhold_lvb - release a LVB
- * @lock: the lock the LVB is associated with
- * @lvb: the lock value block
- *
- */
-
-static void nolock_unhold_lvb(void *lock, char *lvb)
-{
-	kfree(lvb);
-}
-
-static int nolock_plock_get(void *lockspace, struct lm_lockname *name,
-			    struct file *file, struct file_lock *fl)
-{
-	posix_test_lock(file, fl);
-
-	return 0;
-}
-
-static int nolock_plock(void *lockspace, struct lm_lockname *name,
-			struct file *file, int cmd, struct file_lock *fl)
-{
-	int error;
-	error = posix_lock_file_wait(file, fl);
-	return error;
-}
-
-static int nolock_punlock(void *lockspace, struct lm_lockname *name,
-			  struct file *file, struct file_lock *fl)
-{
-	int error;
-	error = posix_lock_file_wait(file, fl);
-	return error;
-}
-
-static void nolock_recovery_done(void *lockspace, unsigned int jid,
-				 unsigned int message)
-{
-}
-
-static const struct lm_lockops nolock_ops = {
-	.lm_proto_name = "lock_nolock",
-	.lm_mount = nolock_mount,
-	.lm_others_may_mount = nolock_others_may_mount,
-	.lm_unmount = nolock_unmount,
-	.lm_withdraw = nolock_withdraw,
-	.lm_get_lock = nolock_get_lock,
-	.lm_put_lock = nolock_put_lock,
-	.lm_lock = nolock_lock,
-	.lm_unlock = nolock_unlock,
-	.lm_cancel = nolock_cancel,
-	.lm_hold_lvb = nolock_hold_lvb,
-	.lm_unhold_lvb = nolock_unhold_lvb,
-	.lm_plock_get = nolock_plock_get,
-	.lm_plock = nolock_plock,
-	.lm_punlock = nolock_punlock,
-	.lm_recovery_done = nolock_recovery_done,
-	.lm_owner = THIS_MODULE,
-};
-
-static int __init init_nolock(void)
-{
-	int error;
-
-	error = gfs2_register_lockproto(&nolock_ops);
-	if (error) {
-		printk(KERN_WARNING
-		       "lock_nolock: can't register protocol: %d\n", error);
-		return error;
-	}
-
-	printk(KERN_INFO
-	       "Lock_Nolock (built %s %s) installed\n", __DATE__, __TIME__);
-	return 0;
-}
-
-static void __exit exit_nolock(void)
-{
-	gfs2_unregister_lockproto(&nolock_ops);
-}
-
-module_init(init_nolock);
-module_exit(exit_nolock);
-
-MODULE_DESCRIPTION("GFS Nolock Locking Module");
-MODULE_AUTHOR("Red Hat, Inc.");
-MODULE_LICENSE("GPL");
-
diff --git a/fs/gfs2/log.c b/fs/gfs2/log.c
index 548264b1836..6c6af9f5e3a 100644
--- a/fs/gfs2/log.c
+++ b/fs/gfs2/log.c
@@ -87,6 +87,8 @@ void gfs2_remove_from_ail(struct gfs2_bufdata *bd)
  */
 
 static void gfs2_ail1_start_one(struct gfs2_sbd *sdp, struct gfs2_ail *ai)
+__releases(&sdp->sd_log_lock)
+__acquires(&sdp->sd_log_lock)
 {
 	struct gfs2_bufdata *bd, *s;
 	struct buffer_head *bh;
diff --git a/fs/gfs2/log.h b/fs/gfs2/log.h
index 77115281650..7c64510ccfd 100644
--- a/fs/gfs2/log.h
+++ b/fs/gfs2/log.h
@@ -21,6 +21,7 @@
  */
 
 static inline void gfs2_log_lock(struct gfs2_sbd *sdp)
+__acquires(&sdp->sd_log_lock)
 {
 	spin_lock(&sdp->sd_log_lock);
 }
@@ -32,6 +33,7 @@ static inline void gfs2_log_lock(struct gfs2_sbd *sdp)
  */
 
 static inline void gfs2_log_unlock(struct gfs2_sbd *sdp)
+__releases(&sdp->sd_log_lock)
 {
 	spin_unlock(&sdp->sd_log_lock);
 }
diff --git a/fs/gfs2/main.c b/fs/gfs2/main.c
index 053e2ebbbd5..bcc668d0fad 100644
--- a/fs/gfs2/main.c
+++ b/fs/gfs2/main.c
@@ -40,8 +40,6 @@ static void gfs2_init_glock_once(struct kmem_cache *cachep, void *foo)
 	INIT_HLIST_NODE(&gl->gl_list);
 	spin_lock_init(&gl->gl_spin);
 	INIT_LIST_HEAD(&gl->gl_holders);
-	INIT_LIST_HEAD(&gl->gl_waiters1);
-	INIT_LIST_HEAD(&gl->gl_waiters3);
 	gl->gl_lvb = NULL;
 	atomic_set(&gl->gl_lvb_count, 0);
 	INIT_LIST_HEAD(&gl->gl_reclaim);
diff --git a/fs/gfs2/meta_io.c b/fs/gfs2/meta_io.c
index 78d75f892f8..09853620c95 100644
--- a/fs/gfs2/meta_io.c
+++ b/fs/gfs2/meta_io.c
@@ -129,7 +129,7 @@ void gfs2_meta_sync(struct gfs2_glock *gl)
 }
 
 /**
- * getbuf - Get a buffer with a given address space
+ * gfs2_getbuf - Get a buffer with a given address space
  * @gl: the glock
  * @blkno: the block number (filesystem scope)
  * @create: 1 if the buffer should be created
@@ -137,7 +137,7 @@ void gfs2_meta_sync(struct gfs2_glock *gl)
  * Returns: the buffer
  */
 
-static struct buffer_head *getbuf(struct gfs2_glock *gl, u64 blkno, int create)
+struct buffer_head *gfs2_getbuf(struct gfs2_glock *gl, u64 blkno, int create)
 {
 	struct address_space *mapping = gl->gl_aspace->i_mapping;
 	struct gfs2_sbd *sdp = gl->gl_sbd;
@@ -205,7 +205,7 @@ static void meta_prep_new(struct buffer_head *bh)
 struct buffer_head *gfs2_meta_new(struct gfs2_glock *gl, u64 blkno)
 {
 	struct buffer_head *bh;
-	bh = getbuf(gl, blkno, CREATE);
+	bh = gfs2_getbuf(gl, blkno, CREATE);
 	meta_prep_new(bh);
 	return bh;
 }
@@ -223,7 +223,7 @@ struct buffer_head *gfs2_meta_new(struct gfs2_glock *gl, u64 blkno)
 int gfs2_meta_read(struct gfs2_glock *gl, u64 blkno, int flags,
 		   struct buffer_head **bhp)
 {
-	*bhp = getbuf(gl, blkno, CREATE);
+	*bhp = gfs2_getbuf(gl, blkno, CREATE);
 	if (!buffer_uptodate(*bhp)) {
 		ll_rw_block(READ_META, 1, bhp);
 		if (flags & DIO_WAIT) {
@@ -346,7 +346,7 @@ void gfs2_meta_wipe(struct gfs2_inode *ip, u64 bstart, u32 blen)
 	struct buffer_head *bh;
 
 	while (blen) {
-		bh = getbuf(ip->i_gl, bstart, NO_CREATE);
+		bh = gfs2_getbuf(ip->i_gl, bstart, NO_CREATE);
 		if (bh) {
 			lock_buffer(bh);
 			gfs2_log_lock(sdp);
@@ -421,7 +421,7 @@ struct buffer_head *gfs2_meta_ra(struct gfs2_glock *gl, u64 dblock, u32 extlen)
 	if (extlen > max_ra)
 		extlen = max_ra;
 
-	first_bh = getbuf(gl, dblock, CREATE);
+	first_bh = gfs2_getbuf(gl, dblock, CREATE);
 
 	if (buffer_uptodate(first_bh))
 		goto out;
@@ -432,7 +432,7 @@ struct buffer_head *gfs2_meta_ra(struct gfs2_glock *gl, u64 dblock, u32 extlen)
 	extlen--;
 
 	while (extlen) {
-		bh = getbuf(gl, dblock, CREATE);
+		bh = gfs2_getbuf(gl, dblock, CREATE);
 
 		if (!buffer_uptodate(bh) && !buffer_locked(bh))
 			ll_rw_block(READA, 1, &bh);
diff --git a/fs/gfs2/meta_io.h b/fs/gfs2/meta_io.h
index 73e3b1c76fe..b1a5f3674d4 100644
--- a/fs/gfs2/meta_io.h
+++ b/fs/gfs2/meta_io.h
@@ -47,6 +47,7 @@ struct buffer_head *gfs2_meta_new(struct gfs2_glock *gl, u64 blkno);
 int gfs2_meta_read(struct gfs2_glock *gl, u64 blkno,
 		   int flags, struct buffer_head **bhp);
 int gfs2_meta_wait(struct gfs2_sbd *sdp, struct buffer_head *bh);
+struct buffer_head *gfs2_getbuf(struct gfs2_glock *gl, u64 blkno, int create);
 
 void gfs2_attach_bufdata(struct gfs2_glock *gl, struct buffer_head *bh,
 			 int meta);
diff --git a/fs/gfs2/ops_address.c b/fs/gfs2/ops_address.c
index f55394e57cb..e64a1b04117 100644
--- a/fs/gfs2/ops_address.c
+++ b/fs/gfs2/ops_address.c
@@ -499,34 +499,34 @@ static int __gfs2_readpage(void *file, struct page *page)
  * @file: The file to read
  * @page: The page of the file
  *
- * This deals with the locking required. We use a trylock in order to
- * avoid the page lock / glock ordering problems returning AOP_TRUNCATED_PAGE
- * in the event that we are unable to get the lock.
+ * This deals with the locking required. We have to unlock and
+ * relock the page in order to get the locking in the right
+ * order.
  */
 
 static int gfs2_readpage(struct file *file, struct page *page)
 {
-	struct gfs2_inode *ip = GFS2_I(page->mapping->host);
-	struct gfs2_holder *gh;
+	struct address_space *mapping = page->mapping;
+	struct gfs2_inode *ip = GFS2_I(mapping->host);
+	struct gfs2_holder gh;
 	int error;
 
-	gh = gfs2_glock_is_locked_by_me(ip->i_gl);
-	if (!gh) {
-		gh = kmalloc(sizeof(struct gfs2_holder), GFP_NOFS);
-		if (!gh)
-			return -ENOBUFS;
-		gfs2_holder_init(ip->i_gl, LM_ST_SHARED, GL_ATIME, gh);
+	unlock_page(page);
+	gfs2_holder_init(ip->i_gl, LM_ST_SHARED, GL_ATIME, &gh);
+	error = gfs2_glock_nq_atime(&gh);
+	if (unlikely(error))
+		goto out;
+	error = AOP_TRUNCATED_PAGE;
+	lock_page(page);
+	if (page->mapping == mapping && !PageUptodate(page))
+		error = __gfs2_readpage(file, page);
+	else
 		unlock_page(page);
-		error = gfs2_glock_nq_atime(gh);
-		if (likely(error != 0))
-			goto out;
-		return AOP_TRUNCATED_PAGE;
-	}
-	error = __gfs2_readpage(file, page);
-	gfs2_glock_dq(gh);
+	gfs2_glock_dq(&gh);
 out:
-	gfs2_holder_uninit(gh);
-	kfree(gh);
+	gfs2_holder_uninit(&gh);
+	if (error && error != AOP_TRUNCATED_PAGE)
+		lock_page(page);
 	return error;
 }
 
diff --git a/fs/gfs2/ops_file.c b/fs/gfs2/ops_file.c
index e1b7d525a06..e9a366d4411 100644
--- a/fs/gfs2/ops_file.c
+++ b/fs/gfs2/ops_file.c
@@ -15,6 +15,7 @@
 #include <linux/uio.h>
 #include <linux/blkdev.h>
 #include <linux/mm.h>
+#include <linux/mount.h>
 #include <linux/fs.h>
 #include <linux/gfs2_ondisk.h>
 #include <linux/ext2_fs.h>
@@ -62,11 +63,11 @@ static loff_t gfs2_llseek(struct file *file, loff_t offset, int origin)
 		error = gfs2_glock_nq_init(ip->i_gl, LM_ST_SHARED, LM_FLAG_ANY,
 					   &i_gh);
 		if (!error) {
-			error = remote_llseek(file, offset, origin);
+			error = generic_file_llseek_unlocked(file, offset, origin);
 			gfs2_glock_dq_uninit(&i_gh);
 		}
 	} else
-		error = remote_llseek(file, offset, origin);
+		error = generic_file_llseek_unlocked(file, offset, origin);
 
 	return error;
 }
@@ -133,7 +134,6 @@ static const u32 fsflags_to_gfs2[32] = {
 	[7] = GFS2_DIF_NOATIME,
 	[12] = GFS2_DIF_EXHASH,
 	[14] = GFS2_DIF_INHERIT_JDATA,
-	[20] = GFS2_DIF_INHERIT_DIRECTIO,
 };
 
 static const u32 gfs2_to_fsflags[32] = {
@@ -142,7 +142,6 @@ static const u32 gfs2_to_fsflags[32] = {
 	[gfs2fl_AppendOnly] = FS_APPEND_FL,
 	[gfs2fl_NoAtime] = FS_NOATIME_FL,
 	[gfs2fl_ExHash] = FS_INDEX_FL,
-	[gfs2fl_InheritDirectio] = FS_DIRECTIO_FL,
 	[gfs2fl_InheritJdata] = FS_JOURNAL_DATA_FL,
 };
 
@@ -160,12 +159,8 @@ static int gfs2_get_flags(struct file *filp, u32 __user *ptr)
 		return error;
 
 	fsflags = fsflags_cvt(gfs2_to_fsflags, ip->i_di.di_flags);
-	if (!S_ISDIR(inode->i_mode)) {
-		if (ip->i_di.di_flags & GFS2_DIF_JDATA)
-			fsflags |= FS_JOURNAL_DATA_FL;
-		if (ip->i_di.di_flags & GFS2_DIF_DIRECTIO)
-			fsflags |= FS_DIRECTIO_FL;
-	}
+	if (!S_ISDIR(inode->i_mode) && ip->i_di.di_flags & GFS2_DIF_JDATA)
+		fsflags |= FS_JOURNAL_DATA_FL;
 	if (put_user(fsflags, ptr))
 		error = -EFAULT;
 
@@ -194,13 +189,11 @@ void gfs2_set_inode_flags(struct inode *inode)
 
 /* Flags that can be set by user space */
 #define GFS2_FLAGS_USER_SET (GFS2_DIF_JDATA|			\
-			     GFS2_DIF_DIRECTIO|			\
 			     GFS2_DIF_IMMUTABLE|		\
 			     GFS2_DIF_APPENDONLY|		\
 			     GFS2_DIF_NOATIME|			\
 			     GFS2_DIF_SYNC|			\
 			     GFS2_DIF_SYSTEM|			\
-			     GFS2_DIF_INHERIT_DIRECTIO|		\
 			     GFS2_DIF_INHERIT_JDATA)
 
 /**
@@ -220,10 +213,14 @@ static int do_gfs2_set_flags(struct file *filp, u32 reqflags, u32 mask)
 	int error;
 	u32 new_flags, flags;
 
-	error = gfs2_glock_nq_init(ip->i_gl, LM_ST_EXCLUSIVE, 0, &gh);
+	error = mnt_want_write(filp->f_path.mnt);
 	if (error)
 		return error;
 
+	error = gfs2_glock_nq_init(ip->i_gl, LM_ST_EXCLUSIVE, 0, &gh);
+	if (error)
+		goto out_drop_write;
+
 	flags = ip->i_di.di_flags;
 	new_flags = (flags & ~mask) | (reqflags & mask);
 	if ((new_flags ^ flags) == 0)
@@ -242,7 +239,7 @@ static int do_gfs2_set_flags(struct file *filp, u32 reqflags, u32 mask)
 	    !capable(CAP_LINUX_IMMUTABLE))
 		goto out;
 	if (!IS_IMMUTABLE(inode)) {
-		error = permission(inode, MAY_WRITE, NULL);
+		error = gfs2_permission(inode, MAY_WRITE);
 		if (error)
 			goto out;
 	}
@@ -272,6 +269,8 @@ out_trans_end:
 	gfs2_trans_end(sdp);
 out:
 	gfs2_glock_dq_uninit(&gh);
+out_drop_write:
+	mnt_drop_write(filp->f_path.mnt);
 	return error;
 }
 
@@ -285,8 +284,6 @@ static int gfs2_set_flags(struct file *filp, u32 __user *ptr)
 	if (!S_ISDIR(inode->i_mode)) {
 		if (gfsflags & GFS2_DIF_INHERIT_JDATA)
 			gfsflags ^= (GFS2_DIF_JDATA | GFS2_DIF_INHERIT_JDATA);
-		if (gfsflags & GFS2_DIF_INHERIT_DIRECTIO)
-			gfsflags ^= (GFS2_DIF_DIRECTIO | GFS2_DIF_INHERIT_DIRECTIO);
 		return do_gfs2_set_flags(filp, gfsflags, ~0);
 	}
 	return do_gfs2_set_flags(filp, gfsflags, ~GFS2_DIF_JDATA);
@@ -487,11 +484,6 @@ static int gfs2_open(struct inode *inode, struct file *file)
 			goto fail_gunlock;
 		}
 
-		/* Listen to the Direct I/O flag */
-
-		if (ip->i_di.di_flags & GFS2_DIF_DIRECTIO)
-			file->f_flags |= O_DIRECT;
-
 		gfs2_glock_dq_uninit(&i_gh);
 	}
 
@@ -669,8 +661,7 @@ static int do_flock(struct file *file, int cmd, struct file_lock *fl)
 	int error = 0;
 
 	state = (fl->fl_type == F_WRLCK) ? LM_ST_EXCLUSIVE : LM_ST_SHARED;
-	flags = (IS_SETLKW(cmd) ? 0 : LM_FLAG_TRY) | GL_EXACT | GL_NOCACHE 
-		| GL_FLOCK;
+	flags = (IS_SETLKW(cmd) ? 0 : LM_FLAG_TRY) | GL_EXACT | GL_NOCACHE;
 
 	mutex_lock(&fp->f_fl_mutex);
 
@@ -683,9 +674,8 @@ static int do_flock(struct file *file, int cmd, struct file_lock *fl)
 		gfs2_glock_dq_wait(fl_gh);
 		gfs2_holder_reinit(state, flags, fl_gh);
 	} else {
-		error = gfs2_glock_get(GFS2_SB(&ip->i_inode),
-				      ip->i_no_addr, &gfs2_flock_glops,
-				      CREATE, &gl);
+		error = gfs2_glock_get(GFS2_SB(&ip->i_inode), ip->i_no_addr,
+				       &gfs2_flock_glops, CREATE, &gl);
 		if (error)
 			goto out;
 		gfs2_holder_init(gl, state, flags, fl_gh);
diff --git a/fs/gfs2/ops_fstype.c b/fs/gfs2/ops_fstype.c
index b2028c82e8d..b4d1d649063 100644
--- a/fs/gfs2/ops_fstype.c
+++ b/fs/gfs2/ops_fstype.c
@@ -64,7 +64,6 @@ static struct gfs2_sbd *init_sbd(struct super_block *sb)
 	mutex_init(&sdp->sd_rindex_mutex);
 	INIT_LIST_HEAD(&sdp->sd_rindex_list);
 	INIT_LIST_HEAD(&sdp->sd_rindex_mru_list);
-	INIT_LIST_HEAD(&sdp->sd_rindex_recent_list);
 
 	INIT_LIST_HEAD(&sdp->sd_jindex_list);
 	spin_lock_init(&sdp->sd_jindex_spin);
@@ -364,6 +363,8 @@ static int map_journal_extents(struct gfs2_sbd *sdp)
 
 static void gfs2_lm_others_may_mount(struct gfs2_sbd *sdp)
 {
+	if (!sdp->sd_lockstruct.ls_ops->lm_others_may_mount)
+		return;
 	if (likely(!test_bit(SDF_SHUTDOWN, &sdp->sd_flags)))
 		sdp->sd_lockstruct.ls_ops->lm_others_may_mount(
 					sdp->sd_lockstruct.ls_lockspace);
@@ -741,8 +742,7 @@ static int gfs2_lm_mount(struct gfs2_sbd *sdp, int silent)
 		goto out;
 	}
 
-	if (gfs2_assert_warn(sdp, sdp->sd_lockstruct.ls_lockspace) ||
-	    gfs2_assert_warn(sdp, sdp->sd_lockstruct.ls_ops) ||
+	if (gfs2_assert_warn(sdp, sdp->sd_lockstruct.ls_ops) ||
 	    gfs2_assert_warn(sdp, sdp->sd_lockstruct.ls_lvb_size >=
 				  GFS2_MIN_LVB_SIZE)) {
 		gfs2_unmount_lockproto(&sdp->sd_lockstruct);
@@ -873,7 +873,7 @@ fail_sb:
 fail_locking:
 	init_locking(sdp, &mount_gh, UNDO);
 fail_lm:
-	gfs2_gl_hash_clear(sdp, WAIT);
+	gfs2_gl_hash_clear(sdp);
 	gfs2_lm_unmount(sdp);
 	while (invalidate_inodes(sb))
 		yield();
diff --git a/fs/gfs2/ops_inode.c b/fs/gfs2/ops_inode.c
index 2686ad4c002..1e252dfc529 100644
--- a/fs/gfs2/ops_inode.c
+++ b/fs/gfs2/ops_inode.c
@@ -163,7 +163,7 @@ static int gfs2_link(struct dentry *old_dentry, struct inode *dir,
 	if (error)
 		goto out;
 
-	error = permission(dir, MAY_WRITE | MAY_EXEC, NULL);
+	error = gfs2_permission(dir, MAY_WRITE | MAY_EXEC);
 	if (error)
 		goto out_gunlock;
 
@@ -669,7 +669,7 @@ static int gfs2_rename(struct inode *odir, struct dentry *odentry,
 			}
 		}
 	} else {
-		error = permission(ndir, MAY_WRITE | MAY_EXEC, NULL);
+		error = gfs2_permission(ndir, MAY_WRITE | MAY_EXEC);
 		if (error)
 			goto out_gunlock;
 
@@ -704,7 +704,7 @@ static int gfs2_rename(struct inode *odir, struct dentry *odentry,
 	/* Check out the dir to be renamed */
 
 	if (dir_rename) {
-		error = permission(odentry->d_inode, MAY_WRITE, NULL);
+		error = gfs2_permission(odentry->d_inode, MAY_WRITE);
 		if (error)
 			goto out_gunlock;
 	}
@@ -891,7 +891,7 @@ static void *gfs2_follow_link(struct dentry *dentry, struct nameidata *nd)
  * Returns: errno
  */
 
-static int gfs2_permission(struct inode *inode, int mask, struct nameidata *nd)
+int gfs2_permission(struct inode *inode, int mask)
 {
 	struct gfs2_inode *ip = GFS2_I(inode);
 	struct gfs2_holder i_gh;
@@ -905,13 +905,22 @@ static int gfs2_permission(struct inode *inode, int mask, struct nameidata *nd)
 		unlock = 1;
 	}
 
-	error = generic_permission(inode, mask, gfs2_check_acl);
+	if ((mask & MAY_WRITE) && IS_IMMUTABLE(inode))
+		error = -EACCES;
+	else
+		error = generic_permission(inode, mask, gfs2_check_acl);
 	if (unlock)
 		gfs2_glock_dq_uninit(&i_gh);
 
 	return error;
 }
 
+static int gfs2_iop_permission(struct inode *inode, int mask,
+			       struct nameidata *nd)
+{
+	return gfs2_permission(inode, mask);
+}
+
 static int setattr_size(struct inode *inode, struct iattr *attr)
 {
 	struct gfs2_inode *ip = GFS2_I(inode);
@@ -1141,7 +1150,7 @@ static int gfs2_removexattr(struct dentry *dentry, const char *name)
 }
 
 const struct inode_operations gfs2_file_iops = {
-	.permission = gfs2_permission,
+	.permission = gfs2_iop_permission,
 	.setattr = gfs2_setattr,
 	.getattr = gfs2_getattr,
 	.setxattr = gfs2_setxattr,
@@ -1160,7 +1169,7 @@ const struct inode_operations gfs2_dir_iops = {
 	.rmdir = gfs2_rmdir,
 	.mknod = gfs2_mknod,
 	.rename = gfs2_rename,
-	.permission = gfs2_permission,
+	.permission = gfs2_iop_permission,
 	.setattr = gfs2_setattr,
 	.getattr = gfs2_getattr,
 	.setxattr = gfs2_setxattr,
@@ -1172,7 +1181,7 @@ const struct inode_operations gfs2_dir_iops = {
 const struct inode_operations gfs2_symlink_iops = {
 	.readlink = gfs2_readlink,
 	.follow_link = gfs2_follow_link,
-	.permission = gfs2_permission,
+	.permission = gfs2_iop_permission,
 	.setattr = gfs2_setattr,
 	.getattr = gfs2_getattr,
 	.setxattr = gfs2_setxattr,
diff --git a/fs/gfs2/ops_super.c b/fs/gfs2/ops_super.c
index 0b7cc920eb8..f66ea0f7a35 100644
--- a/fs/gfs2/ops_super.c
+++ b/fs/gfs2/ops_super.c
@@ -126,7 +126,7 @@ static void gfs2_put_super(struct super_block *sb)
 	gfs2_clear_rgrpd(sdp);
 	gfs2_jindex_free(sdp);
 	/*  Take apart glock structures and buffer lists  */
-	gfs2_gl_hash_clear(sdp, WAIT);
+	gfs2_gl_hash_clear(sdp);
 	/*  Unmount the locking protocol  */
 	gfs2_lm_unmount(sdp);
 
@@ -155,7 +155,7 @@ static void gfs2_write_super(struct super_block *sb)
 static int gfs2_sync_fs(struct super_block *sb, int wait)
 {
 	sb->s_dirt = 0;
-	if (wait)
+	if (wait && sb->s_fs_info)
 		gfs2_log_flush(sb->s_fs_info, NULL);
 	return 0;
 }
diff --git a/fs/gfs2/quota.c b/fs/gfs2/quota.c
index 56aaf915c59..3e073f5144f 100644
--- a/fs/gfs2/quota.c
+++ b/fs/gfs2/quota.c
@@ -904,7 +904,7 @@ static int need_sync(struct gfs2_quota_data *qd)
 		do_sync = 0;
 	else {
 		value *= gfs2_jindex_size(sdp) * num;
-		do_div(value, den);
+		value = div_s64(value, den);
 		value += (s64)be64_to_cpu(qd->qd_qb.qb_value);
 		if (value < (s64)be64_to_cpu(qd->qd_qb.qb_limit))
 			do_sync = 0;
diff --git a/fs/gfs2/recovery.c b/fs/gfs2/recovery.c
index 2888e4b4b1c..d5e91f4f6a0 100644
--- a/fs/gfs2/recovery.c
+++ b/fs/gfs2/recovery.c
@@ -428,6 +428,9 @@ static int clean_journal(struct gfs2_jdesc *jd, struct gfs2_log_header_host *hea
 static void gfs2_lm_recovery_done(struct gfs2_sbd *sdp, unsigned int jid,
 				  unsigned int message)
 {
+	if (!sdp->sd_lockstruct.ls_ops->lm_recovery_done)
+		return;
+
 	if (likely(!test_bit(SDF_SHUTDOWN, &sdp->sd_flags)))
 		sdp->sd_lockstruct.ls_ops->lm_recovery_done(
 			sdp->sd_lockstruct.ls_lockspace, jid, message);
@@ -505,7 +508,7 @@ int gfs2_recover_journal(struct gfs2_jdesc *jd)
 
 		error = gfs2_glock_nq_init(sdp->sd_trans_gl, LM_ST_SHARED,
 					   LM_FLAG_NOEXP | LM_FLAG_PRIORITY |
-					   GL_NOCANCEL | GL_NOCACHE, &t_gh);
+					   GL_NOCACHE, &t_gh);
 		if (error)
 			goto fail_gunlock_ji;
 
diff --git a/fs/gfs2/rgrp.c b/fs/gfs2/rgrp.c
index 3401628d742..2d90fb25350 100644
--- a/fs/gfs2/rgrp.c
+++ b/fs/gfs2/rgrp.c
@@ -371,11 +371,6 @@ static void clear_rgrpdi(struct gfs2_sbd *sdp)
 
 	spin_lock(&sdp->sd_rindex_spin);
 	sdp->sd_rindex_forward = NULL;
-	head = &sdp->sd_rindex_recent_list;
-	while (!list_empty(head)) {
-		rgd = list_entry(head->next, struct gfs2_rgrpd, rd_recent);
-		list_del(&rgd->rd_recent);
-	}
 	spin_unlock(&sdp->sd_rindex_spin);
 
 	head = &sdp->sd_rindex_list;
@@ -945,107 +940,30 @@ static struct inode *try_rgrp_unlink(struct gfs2_rgrpd *rgd, u64 *last_unlinked)
 }
 
 /**
- * recent_rgrp_first - get first RG from "recent" list
- * @sdp: The GFS2 superblock
- * @rglast: address of the rgrp used last
- *
- * Returns: The first rgrp in the recent list
- */
-
-static struct gfs2_rgrpd *recent_rgrp_first(struct gfs2_sbd *sdp,
-					    u64 rglast)
-{
-	struct gfs2_rgrpd *rgd;
-
-	spin_lock(&sdp->sd_rindex_spin);
-
-	if (rglast) {
-		list_for_each_entry(rgd, &sdp->sd_rindex_recent_list, rd_recent) {
-			if (rgrp_contains_block(rgd, rglast))
-				goto out;
-		}
-	}
-	rgd = NULL;
-	if (!list_empty(&sdp->sd_rindex_recent_list))
-		rgd = list_entry(sdp->sd_rindex_recent_list.next,
-				 struct gfs2_rgrpd, rd_recent);
-out:
-	spin_unlock(&sdp->sd_rindex_spin);
-	return rgd;
-}
-
-/**
  * recent_rgrp_next - get next RG from "recent" list
  * @cur_rgd: current rgrp
- * @remove:
  *
  * Returns: The next rgrp in the recent list
  */
 
-static struct gfs2_rgrpd *recent_rgrp_next(struct gfs2_rgrpd *cur_rgd,
-					   int remove)
+static struct gfs2_rgrpd *recent_rgrp_next(struct gfs2_rgrpd *cur_rgd)
 {
 	struct gfs2_sbd *sdp = cur_rgd->rd_sbd;
 	struct list_head *head;
 	struct gfs2_rgrpd *rgd;
 
 	spin_lock(&sdp->sd_rindex_spin);
-
-	head = &sdp->sd_rindex_recent_list;
-
-	list_for_each_entry(rgd, head, rd_recent) {
-		if (rgd == cur_rgd) {
-			if (cur_rgd->rd_recent.next != head)
-				rgd = list_entry(cur_rgd->rd_recent.next,
-						 struct gfs2_rgrpd, rd_recent);
-			else
-				rgd = NULL;
-
-			if (remove)
-				list_del(&cur_rgd->rd_recent);
-
-			goto out;
-		}
+	head = &sdp->sd_rindex_mru_list;
+	if (unlikely(cur_rgd->rd_list_mru.next == head)) {
+		spin_unlock(&sdp->sd_rindex_spin);
+		return NULL;
 	}
-
-	rgd = NULL;
-	if (!list_empty(head))
-		rgd = list_entry(head->next, struct gfs2_rgrpd, rd_recent);
-
-out:
+	rgd = list_entry(cur_rgd->rd_list_mru.next, struct gfs2_rgrpd, rd_list_mru);
 	spin_unlock(&sdp->sd_rindex_spin);
 	return rgd;
 }
 
 /**
- * recent_rgrp_add - add an RG to tail of "recent" list
- * @new_rgd: The rgrp to add
- *
- */
-
-static void recent_rgrp_add(struct gfs2_rgrpd *new_rgd)
-{
-	struct gfs2_sbd *sdp = new_rgd->rd_sbd;
-	struct gfs2_rgrpd *rgd;
-	unsigned int count = 0;
-	unsigned int max = sdp->sd_rgrps / gfs2_jindex_size(sdp);
-
-	spin_lock(&sdp->sd_rindex_spin);
-
-	list_for_each_entry(rgd, &sdp->sd_rindex_recent_list, rd_recent) {
-		if (rgd == new_rgd)
-			goto out;
-
-		if (++count >= max)
-			goto out;
-	}
-	list_add_tail(&new_rgd->rd_recent, &sdp->sd_rindex_recent_list);
-
-out:
-	spin_unlock(&sdp->sd_rindex_spin);
-}
-
-/**
  * forward_rgrp_get - get an rgrp to try next from full list
  * @sdp: The GFS2 superblock
  *
@@ -1112,9 +1030,7 @@ static struct inode *get_local_rgrp(struct gfs2_inode *ip, u64 *last_unlinked)
 	int loops = 0;
 	int error, rg_locked;
 
-	/* Try recently successful rgrps */
-
-	rgd = recent_rgrp_first(sdp, ip->i_goal);
+	rgd = gfs2_blk2rgrpd(sdp, ip->i_goal);
 
 	while (rgd) {
 		rg_locked = 0;
@@ -1136,11 +1052,9 @@ static struct inode *get_local_rgrp(struct gfs2_inode *ip, u64 *last_unlinked)
 				gfs2_glock_dq_uninit(&al->al_rgd_gh);
 			if (inode)
 				return inode;
-			rgd = recent_rgrp_next(rgd, 1);
-			break;
-
+			/* fall through */
 		case GLR_TRYFAILED:
-			rgd = recent_rgrp_next(rgd, 0);
+			rgd = recent_rgrp_next(rgd);
 			break;
 
 		default:
@@ -1199,7 +1113,9 @@ static struct inode *get_local_rgrp(struct gfs2_inode *ip, u64 *last_unlinked)
 
 out:
 	if (begin) {
-		recent_rgrp_add(rgd);
+		spin_lock(&sdp->sd_rindex_spin);
+		list_move(&rgd->rd_list_mru, &sdp->sd_rindex_mru_list);
+		spin_unlock(&sdp->sd_rindex_spin);
 		rgd = gfs2_rgrpd_get_next(rgd);
 		if (!rgd)
 			rgd = gfs2_rgrpd_get_first(sdp);
diff --git a/fs/gfs2/super.c b/fs/gfs2/super.c
index 7aeacbc65f3..63a8a902d9d 100644
--- a/fs/gfs2/super.c
+++ b/fs/gfs2/super.c
@@ -65,7 +65,6 @@ void gfs2_tune_init(struct gfs2_tune *gt)
 	gt->gt_quota_quantum = 60;
 	gt->gt_atime_quantum = 3600;
 	gt->gt_new_files_jdata = 0;
-	gt->gt_new_files_directio = 0;
 	gt->gt_max_readahead = 1 << 18;
 	gt->gt_stall_secs = 600;
 	gt->gt_complain_secs = 10;
@@ -941,8 +940,7 @@ static int gfs2_lock_fs_check_clean(struct gfs2_sbd *sdp,
 	}
 
 	error = gfs2_glock_nq_init(sdp->sd_trans_gl, LM_ST_DEFERRED,
-			       LM_FLAG_PRIORITY | GL_NOCACHE,
-			       t_gh);
+				   GL_NOCACHE, t_gh);
 
 	list_for_each_entry(jd, &sdp->sd_jindex_list, jd_list) {
 		error = gfs2_jdesc_check(jd);
diff --git a/fs/gfs2/sys.c b/fs/gfs2/sys.c
index 9ab9fc85ecd..74846559fc3 100644
--- a/fs/gfs2/sys.c
+++ b/fs/gfs2/sys.c
@@ -110,18 +110,6 @@ static ssize_t statfs_sync_store(struct gfs2_sbd *sdp, const char *buf,
 	return len;
 }
 
-static ssize_t shrink_store(struct gfs2_sbd *sdp, const char *buf, size_t len)
-{
-	if (!capable(CAP_SYS_ADMIN))
-		return -EACCES;
-
-	if (simple_strtol(buf, NULL, 0) != 1)
-		return -EINVAL;
-
-	gfs2_gl_hash_clear(sdp, NO_WAIT);
-	return len;
-}
-
 static ssize_t quota_sync_store(struct gfs2_sbd *sdp, const char *buf,
 				size_t len)
 {
@@ -175,7 +163,6 @@ static struct gfs2_attr gfs2_attr_##name = __ATTR(name, mode, show, store)
 GFS2_ATTR(id,                  0444, id_show,       NULL);
 GFS2_ATTR(fsname,              0444, fsname_show,   NULL);
 GFS2_ATTR(freeze,              0644, freeze_show,   freeze_store);
-GFS2_ATTR(shrink,              0200, NULL,          shrink_store);
 GFS2_ATTR(withdraw,            0644, withdraw_show, withdraw_store);
 GFS2_ATTR(statfs_sync,         0200, NULL,          statfs_sync_store);
 GFS2_ATTR(quota_sync,          0200, NULL,          quota_sync_store);
@@ -186,7 +173,6 @@ static struct attribute *gfs2_attrs[] = {
 	&gfs2_attr_id.attr,
 	&gfs2_attr_fsname.attr,
 	&gfs2_attr_freeze.attr,
-	&gfs2_attr_shrink.attr,
 	&gfs2_attr_withdraw.attr,
 	&gfs2_attr_statfs_sync.attr,
 	&gfs2_attr_quota_sync.attr,
@@ -426,7 +412,6 @@ TUNE_ATTR(max_readahead, 0);
 TUNE_ATTR(complain_secs, 0);
 TUNE_ATTR(statfs_slow, 0);
 TUNE_ATTR(new_files_jdata, 0);
-TUNE_ATTR(new_files_directio, 0);
 TUNE_ATTR(quota_simul_sync, 1);
 TUNE_ATTR(quota_cache_secs, 1);
 TUNE_ATTR(stall_secs, 1);
@@ -455,7 +440,6 @@ static struct attribute *tune_attrs[] = {
 	&tune_attr_quotad_secs.attr,
 	&tune_attr_quota_scale.attr,
 	&tune_attr_new_files_jdata.attr,
-	&tune_attr_new_files_directio.attr,
 	NULL,
 };
 
diff --git a/fs/jbd2/checkpoint.c b/fs/jbd2/checkpoint.c
index 6914598022c..91389c8aee8 100644
--- a/fs/jbd2/checkpoint.c
+++ b/fs/jbd2/checkpoint.c
@@ -688,7 +688,6 @@ void __jbd2_journal_drop_transaction(journal_t *journal, transaction_t *transact
 
 	J_ASSERT(transaction->t_state == T_FINISHED);
 	J_ASSERT(transaction->t_buffers == NULL);
-	J_ASSERT(transaction->t_sync_datalist == NULL);
 	J_ASSERT(transaction->t_forget == NULL);
 	J_ASSERT(transaction->t_iobuf_list == NULL);
 	J_ASSERT(transaction->t_shadow_list == NULL);
diff --git a/fs/jbd2/commit.c b/fs/jbd2/commit.c
index a2ed72f7cee..f8b3be87322 100644
--- a/fs/jbd2/commit.c
+++ b/fs/jbd2/commit.c
@@ -22,6 +22,8 @@
 #include <linux/pagemap.h>
 #include <linux/jiffies.h>
 #include <linux/crc32.h>
+#include <linux/writeback.h>
+#include <linux/backing-dev.h>
 
 /*
  * Default IO end handler for temporary BJ_IO buffer_heads.
@@ -37,8 +39,8 @@ static void journal_end_buffer_io_sync(struct buffer_head *bh, int uptodate)
 }
 
 /*
- * When an ext3-ordered file is truncated, it is possible that many pages are
- * not sucessfully freed, because they are attached to a committing transaction.
+ * When an ext4 file is truncated, it is possible that some pages are not
+ * successfully freed, because they are attached to a committing transaction.
  * After the transaction commits, these pages are left on the LRU, with no
  * ->mapping, and with attached buffers.  These pages are trivially reclaimable
  * by the VM, but their apparent absence upsets the VM accounting, and it makes
@@ -80,21 +82,6 @@ nope:
 }
 
 /*
- * Try to acquire jbd_lock_bh_state() against the buffer, when j_list_lock is
- * held.  For ranking reasons we must trylock.  If we lose, schedule away and
- * return 0.  j_list_lock is dropped in this case.
- */
-static int inverted_lock(journal_t *journal, struct buffer_head *bh)
-{
-	if (!jbd_trylock_bh_state(bh)) {
-		spin_unlock(&journal->j_list_lock);
-		schedule();
-		return 0;
-	}
-	return 1;
-}
-
-/*
  * Done it all: now submit the commit record.  We should have
  * cleaned up our previous buffers by now, so if we are in abort
  * mode we can now just skip the rest of the journal write
@@ -112,6 +99,7 @@ static int journal_submit_commit_record(journal_t *journal,
 	struct buffer_head *bh;
 	int ret;
 	int barrier_done = 0;
+	struct timespec now = current_kernel_time();
 
 	if (is_journal_aborted(journal))
 		return 0;
@@ -126,6 +114,8 @@ static int journal_submit_commit_record(journal_t *journal,
 	tmp->h_magic = cpu_to_be32(JBD2_MAGIC_NUMBER);
 	tmp->h_blocktype = cpu_to_be32(JBD2_COMMIT_BLOCK);
 	tmp->h_sequence = cpu_to_be32(commit_transaction->t_tid);
+	tmp->h_commit_sec = cpu_to_be64(now.tv_sec);
+	tmp->h_commit_nsec = cpu_to_be32(now.tv_nsec);
 
 	if (JBD2_HAS_COMPAT_FEATURE(journal,
 				    JBD2_FEATURE_COMPAT_CHECKSUM)) {
@@ -197,159 +187,104 @@ static int journal_wait_on_commit_record(struct buffer_head *bh)
 }
 
 /*
- * Wait for all submitted IO to complete.
+ * write the filemap data using writepage() address_space_operations.
+ * We don't do block allocation here even for delalloc. We don't
+ * use writepages() because with dealyed allocation we may be doing
+ * block allocation in writepages().
  */
-static int journal_wait_on_locked_list(journal_t *journal,
-				       transaction_t *commit_transaction)
+static int journal_submit_inode_data_buffers(struct address_space *mapping)
 {
-	int ret = 0;
-	struct journal_head *jh;
-
-	while (commit_transaction->t_locked_list) {
-		struct buffer_head *bh;
-
-		jh = commit_transaction->t_locked_list->b_tprev;
-		bh = jh2bh(jh);
-		get_bh(bh);
-		if (buffer_locked(bh)) {
-			spin_unlock(&journal->j_list_lock);
-			wait_on_buffer(bh);
-			if (unlikely(!buffer_uptodate(bh)))
-				ret = -EIO;
-			spin_lock(&journal->j_list_lock);
-		}
-		if (!inverted_lock(journal, bh)) {
-			put_bh(bh);
-			spin_lock(&journal->j_list_lock);
-			continue;
-		}
-		if (buffer_jbd(bh) && jh->b_jlist == BJ_Locked) {
-			__jbd2_journal_unfile_buffer(jh);
-			jbd_unlock_bh_state(bh);
-			jbd2_journal_remove_journal_head(bh);
-			put_bh(bh);
-		} else {
-			jbd_unlock_bh_state(bh);
-		}
-		put_bh(bh);
-		cond_resched_lock(&journal->j_list_lock);
-	}
+	int ret;
+	struct writeback_control wbc = {
+		.sync_mode =  WB_SYNC_ALL,
+		.nr_to_write = mapping->nrpages * 2,
+		.range_start = 0,
+		.range_end = i_size_read(mapping->host),
+		.for_writepages = 1,
+	};
+
+	ret = generic_writepages(mapping, &wbc);
 	return ret;
-  }
+}
 
-static void journal_do_submit_data(struct buffer_head **wbuf, int bufs)
+/*
+ * Submit all the data buffers of inode associated with the transaction to
+ * disk.
+ *
+ * We are in a committing transaction. Therefore no new inode can be added to
+ * our inode list. We use JI_COMMIT_RUNNING flag to protect inode we currently
+ * operate on from being released while we write out pages.
+ */
+static int journal_submit_data_buffers(journal_t *journal,
+		transaction_t *commit_transaction)
 {
-	int i;
+	struct jbd2_inode *jinode;
+	int err, ret = 0;
+	struct address_space *mapping;
 
-	for (i = 0; i < bufs; i++) {
-		wbuf[i]->b_end_io = end_buffer_write_sync;
-		/* We use-up our safety reference in submit_bh() */
-		submit_bh(WRITE, wbuf[i]);
+	spin_lock(&journal->j_list_lock);
+	list_for_each_entry(jinode, &commit_transaction->t_inode_list, i_list) {
+		mapping = jinode->i_vfs_inode->i_mapping;
+		jinode->i_flags |= JI_COMMIT_RUNNING;
+		spin_unlock(&journal->j_list_lock);
+		/*
+		 * submit the inode data buffers. We use writepage
+		 * instead of writepages. Because writepages can do
+		 * block allocation  with delalloc. We need to write
+		 * only allocated blocks here.
+		 */
+		err = journal_submit_inode_data_buffers(mapping);
+		if (!ret)
+			ret = err;
+		spin_lock(&journal->j_list_lock);
+		J_ASSERT(jinode->i_transaction == commit_transaction);
+		jinode->i_flags &= ~JI_COMMIT_RUNNING;
+		wake_up_bit(&jinode->i_flags, __JI_COMMIT_RUNNING);
 	}
+	spin_unlock(&journal->j_list_lock);
+	return ret;
 }
 
 /*
- *  Submit all the data buffers to disk
+ * Wait for data submitted for writeout, refile inodes to proper
+ * transaction if needed.
+ *
  */
-static void journal_submit_data_buffers(journal_t *journal,
-				transaction_t *commit_transaction)
+static int journal_finish_inode_data_buffers(journal_t *journal,
+		transaction_t *commit_transaction)
 {
-	struct journal_head *jh;
-	struct buffer_head *bh;
-	int locked;
-	int bufs = 0;
-	struct buffer_head **wbuf = journal->j_wbuf;
+	struct jbd2_inode *jinode, *next_i;
+	int err, ret = 0;
 
-	/*
-	 * Whenever we unlock the journal and sleep, things can get added
-	 * onto ->t_sync_datalist, so we have to keep looping back to
-	 * write_out_data until we *know* that the list is empty.
-	 *
-	 * Cleanup any flushed data buffers from the data list.  Even in
-	 * abort mode, we want to flush this out as soon as possible.
-	 */
-write_out_data:
-	cond_resched();
+	/* For locking, see the comment in journal_submit_data_buffers() */
 	spin_lock(&journal->j_list_lock);
+	list_for_each_entry(jinode, &commit_transaction->t_inode_list, i_list) {
+		jinode->i_flags |= JI_COMMIT_RUNNING;
+		spin_unlock(&journal->j_list_lock);
+		err = filemap_fdatawait(jinode->i_vfs_inode->i_mapping);
+		if (!ret)
+			ret = err;
+		spin_lock(&journal->j_list_lock);
+		jinode->i_flags &= ~JI_COMMIT_RUNNING;
+		wake_up_bit(&jinode->i_flags, __JI_COMMIT_RUNNING);
+	}
 
-	while (commit_transaction->t_sync_datalist) {
-		jh = commit_transaction->t_sync_datalist;
-		bh = jh2bh(jh);
-		locked = 0;
-
-		/* Get reference just to make sure buffer does not disappear
-		 * when we are forced to drop various locks */
-		get_bh(bh);
-		/* If the buffer is dirty, we need to submit IO and hence
-		 * we need the buffer lock. We try to lock the buffer without
-		 * blocking. If we fail, we need to drop j_list_lock and do
-		 * blocking lock_buffer().
-		 */
-		if (buffer_dirty(bh)) {
-			if (test_set_buffer_locked(bh)) {
-				BUFFER_TRACE(bh, "needs blocking lock");
-				spin_unlock(&journal->j_list_lock);
-				/* Write out all data to prevent deadlocks */
-				journal_do_submit_data(wbuf, bufs);
-				bufs = 0;
-				lock_buffer(bh);
-				spin_lock(&journal->j_list_lock);
-			}
-			locked = 1;
-		}
-		/* We have to get bh_state lock. Again out of order, sigh. */
-		if (!inverted_lock(journal, bh)) {
-			jbd_lock_bh_state(bh);
-			spin_lock(&journal->j_list_lock);
-		}
-		/* Someone already cleaned up the buffer? */
-		if (!buffer_jbd(bh)
-			|| jh->b_transaction != commit_transaction
-			|| jh->b_jlist != BJ_SyncData) {
-			jbd_unlock_bh_state(bh);
-			if (locked)
-				unlock_buffer(bh);
-			BUFFER_TRACE(bh, "already cleaned up");
-			put_bh(bh);
-			continue;
-		}
-		if (locked && test_clear_buffer_dirty(bh)) {
-			BUFFER_TRACE(bh, "needs writeout, adding to array");
-			wbuf[bufs++] = bh;
-			__jbd2_journal_file_buffer(jh, commit_transaction,
-						BJ_Locked);
-			jbd_unlock_bh_state(bh);
-			if (bufs == journal->j_wbufsize) {
-				spin_unlock(&journal->j_list_lock);
-				journal_do_submit_data(wbuf, bufs);
-				bufs = 0;
-				goto write_out_data;
-			}
-		} else if (!locked && buffer_locked(bh)) {
-			__jbd2_journal_file_buffer(jh, commit_transaction,
-						BJ_Locked);
-			jbd_unlock_bh_state(bh);
-			put_bh(bh);
+	/* Now refile inode to proper lists */
+	list_for_each_entry_safe(jinode, next_i,
+				 &commit_transaction->t_inode_list, i_list) {
+		list_del(&jinode->i_list);
+		if (jinode->i_next_transaction) {
+			jinode->i_transaction = jinode->i_next_transaction;
+			jinode->i_next_transaction = NULL;
+			list_add(&jinode->i_list,
+				&jinode->i_transaction->t_inode_list);
 		} else {
-			BUFFER_TRACE(bh, "writeout complete: unfile");
-			__jbd2_journal_unfile_buffer(jh);
-			jbd_unlock_bh_state(bh);
-			if (locked)
-				unlock_buffer(bh);
-			jbd2_journal_remove_journal_head(bh);
-			/* Once for our safety reference, once for
-			 * jbd2_journal_remove_journal_head() */
-			put_bh(bh);
-			put_bh(bh);
-		}
-
-		if (need_resched() || spin_needbreak(&journal->j_list_lock)) {
-			spin_unlock(&journal->j_list_lock);
-			goto write_out_data;
+			jinode->i_transaction = NULL;
 		}
 	}
 	spin_unlock(&journal->j_list_lock);
-	journal_do_submit_data(wbuf, bufs);
+
+	return ret;
 }
 
 static __u32 jbd2_checksum_data(__u32 crc32_sum, struct buffer_head *bh)
@@ -524,21 +459,7 @@ void jbd2_journal_commit_transaction(journal_t *journal)
 	 * Now start flushing things to disk, in the order they appear
 	 * on the transaction lists.  Data blocks go first.
 	 */
-	err = 0;
-	journal_submit_data_buffers(journal, commit_transaction);
-
-	/*
-	 * Wait for all previously submitted IO to complete if commit
-	 * record is to be written synchronously.
-	 */
-	spin_lock(&journal->j_list_lock);
-	if (!JBD2_HAS_INCOMPAT_FEATURE(journal,
-		JBD2_FEATURE_INCOMPAT_ASYNC_COMMIT))
-		err = journal_wait_on_locked_list(journal,
-						commit_transaction);
-
-	spin_unlock(&journal->j_list_lock);
-
+	err = journal_submit_data_buffers(journal, commit_transaction);
 	if (err)
 		jbd2_journal_abort(journal, err);
 
@@ -547,16 +468,6 @@ void jbd2_journal_commit_transaction(journal_t *journal)
 	jbd_debug(3, "JBD: commit phase 2\n");
 
 	/*
-	 * If we found any dirty or locked buffers, then we should have
-	 * looped back up to the write_out_data label.  If there weren't
-	 * any then journal_clean_data_list should have wiped the list
-	 * clean by now, so check that it is in fact empty.
-	 */
-	J_ASSERT (commit_transaction->t_sync_datalist == NULL);
-
-	jbd_debug (3, "JBD: commit phase 3\n");
-
-	/*
 	 * Way to go: we have now written out all of the data for a
 	 * transaction!  Now comes the tricky part: we need to write out
 	 * metadata.  Loop over the transaction's entire buffer list:
@@ -574,6 +485,7 @@ void jbd2_journal_commit_transaction(journal_t *journal)
 	J_ASSERT(commit_transaction->t_nr_buffers <=
 		 commit_transaction->t_outstanding_credits);
 
+	err = 0;
 	descriptor = NULL;
 	bufs = 0;
 	while (commit_transaction->t_buffers) {
@@ -748,15 +660,19 @@ start_journal_io:
 						 &cbh, crc32_sum);
 		if (err)
 			__jbd2_journal_abort_hard(journal);
-
-		spin_lock(&journal->j_list_lock);
-		err = journal_wait_on_locked_list(journal,
-						commit_transaction);
-		spin_unlock(&journal->j_list_lock);
-		if (err)
-			__jbd2_journal_abort_hard(journal);
 	}
 
+	/*
+	 * This is the right place to wait for data buffers both for ASYNC
+	 * and !ASYNC commit. If commit is ASYNC, we need to wait only after
+	 * the commit block went to disk (which happens above). If commit is
+	 * SYNC, we need to wait for data buffers before we start writing
+	 * commit block, which happens below in such setting.
+	 */
+	err = journal_finish_inode_data_buffers(journal, commit_transaction);
+	if (err)
+		jbd2_journal_abort(journal, err);
+
 	/* Lo and behold: we have just managed to send a transaction to
            the log.  Before we can commit it, wait for the IO so far to
            complete.  Control buffers being written are on the
@@ -768,7 +684,7 @@ start_journal_io:
 	   so we incur less scheduling load.
 	*/
 
-	jbd_debug(3, "JBD: commit phase 4\n");
+	jbd_debug(3, "JBD: commit phase 3\n");
 
 	/*
 	 * akpm: these are BJ_IO, and j_list_lock is not needed.
@@ -827,7 +743,7 @@ wait_for_iobuf:
 
 	J_ASSERT (commit_transaction->t_shadow_list == NULL);
 
-	jbd_debug(3, "JBD: commit phase 5\n");
+	jbd_debug(3, "JBD: commit phase 4\n");
 
 	/* Here we wait for the revoke record and descriptor record buffers */
  wait_for_ctlbuf:
@@ -854,7 +770,7 @@ wait_for_iobuf:
 		/* AKPM: bforget here */
 	}
 
-	jbd_debug(3, "JBD: commit phase 6\n");
+	jbd_debug(3, "JBD: commit phase 5\n");
 
 	if (!JBD2_HAS_INCOMPAT_FEATURE(journal,
 		JBD2_FEATURE_INCOMPAT_ASYNC_COMMIT)) {
@@ -874,9 +790,9 @@ wait_for_iobuf:
            transaction can be removed from any checkpoint list it was on
            before. */
 
-	jbd_debug(3, "JBD: commit phase 7\n");
+	jbd_debug(3, "JBD: commit phase 6\n");
 
-	J_ASSERT(commit_transaction->t_sync_datalist == NULL);
+	J_ASSERT(list_empty(&commit_transaction->t_inode_list));
 	J_ASSERT(commit_transaction->t_buffers == NULL);
 	J_ASSERT(commit_transaction->t_checkpoint_list == NULL);
 	J_ASSERT(commit_transaction->t_iobuf_list == NULL);
@@ -997,7 +913,7 @@ restart_loop:
 
 	/* Done with this transaction! */
 
-	jbd_debug(3, "JBD: commit phase 8\n");
+	jbd_debug(3, "JBD: commit phase 7\n");
 
 	J_ASSERT(commit_transaction->t_state == T_COMMIT);
 
diff --git a/fs/jbd2/journal.c b/fs/jbd2/journal.c
index 2e24567c4a7..b26c6d9fe6a 100644
--- a/fs/jbd2/journal.c
+++ b/fs/jbd2/journal.c
@@ -50,7 +50,6 @@ EXPORT_SYMBOL(jbd2_journal_unlock_updates);
 EXPORT_SYMBOL(jbd2_journal_get_write_access);
 EXPORT_SYMBOL(jbd2_journal_get_create_access);
 EXPORT_SYMBOL(jbd2_journal_get_undo_access);
-EXPORT_SYMBOL(jbd2_journal_dirty_data);
 EXPORT_SYMBOL(jbd2_journal_dirty_metadata);
 EXPORT_SYMBOL(jbd2_journal_release_buffer);
 EXPORT_SYMBOL(jbd2_journal_forget);
@@ -82,6 +81,10 @@ EXPORT_SYMBOL(jbd2_journal_blocks_per_page);
 EXPORT_SYMBOL(jbd2_journal_invalidatepage);
 EXPORT_SYMBOL(jbd2_journal_try_to_free_buffers);
 EXPORT_SYMBOL(jbd2_journal_force_commit);
+EXPORT_SYMBOL(jbd2_journal_file_inode);
+EXPORT_SYMBOL(jbd2_journal_init_jbd_inode);
+EXPORT_SYMBOL(jbd2_journal_release_jbd_inode);
+EXPORT_SYMBOL(jbd2_journal_begin_ordered_truncate);
 
 static int journal_convert_superblock_v1(journal_t *, journal_superblock_t *);
 static void __journal_abort_soft (journal_t *journal, int errno);
@@ -2195,6 +2198,54 @@ void jbd2_journal_put_journal_head(struct journal_head *jh)
 }
 
 /*
+ * Initialize jbd inode head
+ */
+void jbd2_journal_init_jbd_inode(struct jbd2_inode *jinode, struct inode *inode)
+{
+	jinode->i_transaction = NULL;
+	jinode->i_next_transaction = NULL;
+	jinode->i_vfs_inode = inode;
+	jinode->i_flags = 0;
+	INIT_LIST_HEAD(&jinode->i_list);
+}
+
+/*
+ * Function to be called before we start removing inode from memory (i.e.,
+ * clear_inode() is a fine place to be called from). It removes inode from
+ * transaction's lists.
+ */
+void jbd2_journal_release_jbd_inode(journal_t *journal,
+				    struct jbd2_inode *jinode)
+{
+	int writeout = 0;
+
+	if (!journal)
+		return;
+restart:
+	spin_lock(&journal->j_list_lock);
+	/* Is commit writing out inode - we have to wait */
+	if (jinode->i_flags & JI_COMMIT_RUNNING) {
+		wait_queue_head_t *wq;
+		DEFINE_WAIT_BIT(wait, &jinode->i_flags, __JI_COMMIT_RUNNING);
+		wq = bit_waitqueue(&jinode->i_flags, __JI_COMMIT_RUNNING);
+		prepare_to_wait(wq, &wait.wait, TASK_UNINTERRUPTIBLE);
+		spin_unlock(&journal->j_list_lock);
+		schedule();
+		finish_wait(wq, &wait.wait);
+		goto restart;
+	}
+
+	/* Do we need to wait for data writeback? */
+	if (journal->j_committing_transaction == jinode->i_transaction)
+		writeout = 1;
+	if (jinode->i_transaction) {
+		list_del(&jinode->i_list);
+		jinode->i_transaction = NULL;
+	}
+	spin_unlock(&journal->j_list_lock);
+}
+
+/*
  * debugfs tunables
  */
 #ifdef CONFIG_JBD2_DEBUG
diff --git a/fs/jbd2/transaction.c b/fs/jbd2/transaction.c
index d6e006e6780..4f7cadbb19f 100644
--- a/fs/jbd2/transaction.c
+++ b/fs/jbd2/transaction.c
@@ -41,7 +41,6 @@ static void __jbd2_journal_temp_unlink_buffer(struct journal_head *jh);
  *	new transaction	and we can't block without protecting against other
  *	processes trying to touch the journal while it is in transition.
  *
- * Called under j_state_lock
  */
 
 static transaction_t *
@@ -52,6 +51,7 @@ jbd2_get_transaction(journal_t *journal, transaction_t *transaction)
 	transaction->t_tid = journal->j_transaction_sequence++;
 	transaction->t_expires = jiffies + journal->j_commit_interval;
 	spin_lock_init(&transaction->t_handle_lock);
+	INIT_LIST_HEAD(&transaction->t_inode_list);
 
 	/* Set up the commit timer for the new transaction. */
 	journal->j_commit_timer.expires = round_jiffies(transaction->t_expires);
@@ -943,183 +943,6 @@ out:
 }
 
 /**
- * int jbd2_journal_dirty_data() -  mark a buffer as containing dirty data which
- *                             needs to be flushed before we can commit the
- *                             current transaction.
- * @handle: transaction
- * @bh: bufferhead to mark
- *
- * The buffer is placed on the transaction's data list and is marked as
- * belonging to the transaction.
- *
- * Returns error number or 0 on success.
- *
- * jbd2_journal_dirty_data() can be called via page_launder->ext3_writepage
- * by kswapd.
- */
-int jbd2_journal_dirty_data(handle_t *handle, struct buffer_head *bh)
-{
-	journal_t *journal = handle->h_transaction->t_journal;
-	int need_brelse = 0;
-	struct journal_head *jh;
-
-	if (is_handle_aborted(handle))
-		return 0;
-
-	jh = jbd2_journal_add_journal_head(bh);
-	JBUFFER_TRACE(jh, "entry");
-
-	/*
-	 * The buffer could *already* be dirty.  Writeout can start
-	 * at any time.
-	 */
-	jbd_debug(4, "jh: %p, tid:%d\n", jh, handle->h_transaction->t_tid);
-
-	/*
-	 * What if the buffer is already part of a running transaction?
-	 *
-	 * There are two cases:
-	 * 1) It is part of the current running transaction.  Refile it,
-	 *    just in case we have allocated it as metadata, deallocated
-	 *    it, then reallocated it as data.
-	 * 2) It is part of the previous, still-committing transaction.
-	 *    If all we want to do is to guarantee that the buffer will be
-	 *    written to disk before this new transaction commits, then
-	 *    being sure that the *previous* transaction has this same
-	 *    property is sufficient for us!  Just leave it on its old
-	 *    transaction.
-	 *
-	 * In case (2), the buffer must not already exist as metadata
-	 * --- that would violate write ordering (a transaction is free
-	 * to write its data at any point, even before the previous
-	 * committing transaction has committed).  The caller must
-	 * never, ever allow this to happen: there's nothing we can do
-	 * about it in this layer.
-	 */
-	jbd_lock_bh_state(bh);
-	spin_lock(&journal->j_list_lock);
-
-	/* Now that we have bh_state locked, are we really still mapped? */
-	if (!buffer_mapped(bh)) {
-		JBUFFER_TRACE(jh, "unmapped buffer, bailing out");
-		goto no_journal;
-	}
-
-	if (jh->b_transaction) {
-		JBUFFER_TRACE(jh, "has transaction");
-		if (jh->b_transaction != handle->h_transaction) {
-			JBUFFER_TRACE(jh, "belongs to older transaction");
-			J_ASSERT_JH(jh, jh->b_transaction ==
-					journal->j_committing_transaction);
-
-			/* @@@ IS THIS TRUE  ? */
-			/*
-			 * Not any more.  Scenario: someone does a write()
-			 * in data=journal mode.  The buffer's transaction has
-			 * moved into commit.  Then someone does another
-			 * write() to the file.  We do the frozen data copyout
-			 * and set b_next_transaction to point to j_running_t.
-			 * And while we're in that state, someone does a
-			 * writepage() in an attempt to pageout the same area
-			 * of the file via a shared mapping.  At present that
-			 * calls jbd2_journal_dirty_data(), and we get right here.
-			 * It may be too late to journal the data.  Simply
-			 * falling through to the next test will suffice: the
-			 * data will be dirty and wil be checkpointed.  The
-			 * ordering comments in the next comment block still
-			 * apply.
-			 */
-			//J_ASSERT_JH(jh, jh->b_next_transaction == NULL);
-
-			/*
-			 * If we're journalling data, and this buffer was
-			 * subject to a write(), it could be metadata, forget
-			 * or shadow against the committing transaction.  Now,
-			 * someone has dirtied the same darn page via a mapping
-			 * and it is being writepage()'d.
-			 * We *could* just steal the page from commit, with some
-			 * fancy locking there.  Instead, we just skip it -
-			 * don't tie the page's buffers to the new transaction
-			 * at all.
-			 * Implication: if we crash before the writepage() data
-			 * is written into the filesystem, recovery will replay
-			 * the write() data.
-			 */
-			if (jh->b_jlist != BJ_None &&
-					jh->b_jlist != BJ_SyncData &&
-					jh->b_jlist != BJ_Locked) {
-				JBUFFER_TRACE(jh, "Not stealing");
-				goto no_journal;
-			}
-
-			/*
-			 * This buffer may be undergoing writeout in commit.  We
-			 * can't return from here and let the caller dirty it
-			 * again because that can cause the write-out loop in
-			 * commit to never terminate.
-			 */
-			if (buffer_dirty(bh)) {
-				get_bh(bh);
-				spin_unlock(&journal->j_list_lock);
-				jbd_unlock_bh_state(bh);
-				need_brelse = 1;
-				sync_dirty_buffer(bh);
-				jbd_lock_bh_state(bh);
-				spin_lock(&journal->j_list_lock);
-				/* Since we dropped the lock... */
-				if (!buffer_mapped(bh)) {
-					JBUFFER_TRACE(jh, "buffer got unmapped");
-					goto no_journal;
-				}
-				/* The buffer may become locked again at any
-				   time if it is redirtied */
-			}
-
-			/* journal_clean_data_list() may have got there first */
-			if (jh->b_transaction != NULL) {
-				JBUFFER_TRACE(jh, "unfile from commit");
-				__jbd2_journal_temp_unlink_buffer(jh);
-				/* It still points to the committing
-				 * transaction; move it to this one so
-				 * that the refile assert checks are
-				 * happy. */
-				jh->b_transaction = handle->h_transaction;
-			}
-			/* The buffer will be refiled below */
-
-		}
-		/*
-		 * Special case --- the buffer might actually have been
-		 * allocated and then immediately deallocated in the previous,
-		 * committing transaction, so might still be left on that
-		 * transaction's metadata lists.
-		 */
-		if (jh->b_jlist != BJ_SyncData && jh->b_jlist != BJ_Locked) {
-			JBUFFER_TRACE(jh, "not on correct data list: unfile");
-			J_ASSERT_JH(jh, jh->b_jlist != BJ_Shadow);
-			__jbd2_journal_temp_unlink_buffer(jh);
-			jh->b_transaction = handle->h_transaction;
-			JBUFFER_TRACE(jh, "file as data");
-			__jbd2_journal_file_buffer(jh, handle->h_transaction,
-						BJ_SyncData);
-		}
-	} else {
-		JBUFFER_TRACE(jh, "not on a transaction");
-		__jbd2_journal_file_buffer(jh, handle->h_transaction, BJ_SyncData);
-	}
-no_journal:
-	spin_unlock(&journal->j_list_lock);
-	jbd_unlock_bh_state(bh);
-	if (need_brelse) {
-		BUFFER_TRACE(bh, "brelse");
-		__brelse(bh);
-	}
-	JBUFFER_TRACE(jh, "exit");
-	jbd2_journal_put_journal_head(jh);
-	return 0;
-}
-
-/**
  * int jbd2_journal_dirty_metadata() -  mark a buffer as containing dirty metadata
  * @handle: transaction to add buffer to.
  * @bh: buffer to mark
@@ -1541,10 +1364,10 @@ __blist_del_buffer(struct journal_head **list, struct journal_head *jh)
  * Remove a buffer from the appropriate transaction list.
  *
  * Note that this function can *change* the value of
- * bh->b_transaction->t_sync_datalist, t_buffers, t_forget,
- * t_iobuf_list, t_shadow_list, t_log_list or t_reserved_list.  If the caller
- * is holding onto a copy of one of thee pointers, it could go bad.
- * Generally the caller needs to re-read the pointer from the transaction_t.
+ * bh->b_transaction->t_buffers, t_forget, t_iobuf_list, t_shadow_list,
+ * t_log_list or t_reserved_list.  If the caller is holding onto a copy of one
+ * of these pointers, it could go bad.  Generally the caller needs to re-read
+ * the pointer from the transaction_t.
  *
  * Called under j_list_lock.  The journal may not be locked.
  */
@@ -1566,9 +1389,6 @@ void __jbd2_journal_temp_unlink_buffer(struct journal_head *jh)
 	switch (jh->b_jlist) {
 	case BJ_None:
 		return;
-	case BJ_SyncData:
-		list = &transaction->t_sync_datalist;
-		break;
 	case BJ_Metadata:
 		transaction->t_nr_buffers--;
 		J_ASSERT_JH(jh, transaction->t_nr_buffers >= 0);
@@ -1589,9 +1409,6 @@ void __jbd2_journal_temp_unlink_buffer(struct journal_head *jh)
 	case BJ_Reserved:
 		list = &transaction->t_reserved_list;
 		break;
-	case BJ_Locked:
-		list = &transaction->t_locked_list;
-		break;
 	}
 
 	__blist_del_buffer(list, jh);
@@ -1634,15 +1451,7 @@ __journal_try_to_free_buffer(journal_t *journal, struct buffer_head *bh)
 		goto out;
 
 	spin_lock(&journal->j_list_lock);
-	if (jh->b_transaction != NULL && jh->b_cp_transaction == NULL) {
-		if (jh->b_jlist == BJ_SyncData || jh->b_jlist == BJ_Locked) {
-			/* A written-back ordered data buffer */
-			JBUFFER_TRACE(jh, "release data");
-			__jbd2_journal_unfile_buffer(jh);
-			jbd2_journal_remove_journal_head(bh);
-			__brelse(bh);
-		}
-	} else if (jh->b_cp_transaction != NULL && jh->b_transaction == NULL) {
+	if (jh->b_cp_transaction != NULL && jh->b_transaction == NULL) {
 		/* written-back checkpointed metadata buffer */
 		if (jh->b_jlist == BJ_None) {
 			JBUFFER_TRACE(jh, "remove from checkpoint list");
@@ -1656,12 +1465,43 @@ out:
 	return;
 }
 
+/*
+ * jbd2_journal_try_to_free_buffers() could race with
+ * jbd2_journal_commit_transaction(). The later might still hold the
+ * reference count to the buffers when inspecting them on
+ * t_syncdata_list or t_locked_list.
+ *
+ * jbd2_journal_try_to_free_buffers() will call this function to
+ * wait for the current transaction to finish syncing data buffers, before
+ * try to free that buffer.
+ *
+ * Called with journal->j_state_lock hold.
+ */
+static void jbd2_journal_wait_for_transaction_sync_data(journal_t *journal)
+{
+	transaction_t *transaction;
+	tid_t tid;
+
+	spin_lock(&journal->j_state_lock);
+	transaction = journal->j_committing_transaction;
+
+	if (!transaction) {
+		spin_unlock(&journal->j_state_lock);
+		return;
+	}
+
+	tid = transaction->t_tid;
+	spin_unlock(&journal->j_state_lock);
+	jbd2_log_wait_commit(journal, tid);
+}
 
 /**
  * int jbd2_journal_try_to_free_buffers() - try to free page buffers.
  * @journal: journal for operation
  * @page: to try and free
- * @unused_gfp_mask: unused
+ * @gfp_mask: we use the mask to detect how hard should we try to release
+ * buffers. If __GFP_WAIT and __GFP_FS is set, we wait for commit code to
+ * release the buffers.
  *
  *
  * For all the buffers on this page,
@@ -1690,9 +1530,11 @@ out:
  * journal_try_to_free_buffer() is changing its state.  But that
  * cannot happen because we never reallocate freed data as metadata
  * while the data is part of a transaction.  Yes?
+ *
+ * Return 0 on failure, 1 on success
  */
 int jbd2_journal_try_to_free_buffers(journal_t *journal,
-				struct page *page, gfp_t unused_gfp_mask)
+				struct page *page, gfp_t gfp_mask)
 {
 	struct buffer_head *head;
 	struct buffer_head *bh;
@@ -1708,7 +1550,8 @@ int jbd2_journal_try_to_free_buffers(journal_t *journal,
 		/*
 		 * We take our own ref against the journal_head here to avoid
 		 * having to add tons of locking around each instance of
-		 * jbd2_journal_remove_journal_head() and jbd2_journal_put_journal_head().
+		 * jbd2_journal_remove_journal_head() and
+		 * jbd2_journal_put_journal_head().
 		 */
 		jh = jbd2_journal_grab_journal_head(bh);
 		if (!jh)
@@ -1721,7 +1564,28 @@ int jbd2_journal_try_to_free_buffers(journal_t *journal,
 		if (buffer_jbd(bh))
 			goto busy;
 	} while ((bh = bh->b_this_page) != head);
+
 	ret = try_to_free_buffers(page);
+
+	/*
+	 * There are a number of places where jbd2_journal_try_to_free_buffers()
+	 * could race with jbd2_journal_commit_transaction(), the later still
+	 * holds the reference to the buffers to free while processing them.
+	 * try_to_free_buffers() failed to free those buffers. Some of the
+	 * caller of releasepage() request page buffers to be dropped, otherwise
+	 * treat the fail-to-free as errors (such as generic_file_direct_IO())
+	 *
+	 * So, if the caller of try_to_release_page() wants the synchronous
+	 * behaviour(i.e make sure buffers are dropped upon return),
+	 * let's wait for the current transaction to finish flush of
+	 * dirty data buffers, then try to free those buffers again,
+	 * with the journal locked.
+	 */
+	if (ret == 0 && (gfp_mask & __GFP_WAIT) && (gfp_mask & __GFP_FS)) {
+		jbd2_journal_wait_for_transaction_sync_data(journal);
+		ret = try_to_free_buffers(page);
+	}
+
 busy:
 	return ret;
 }
@@ -1823,6 +1687,7 @@ static int journal_unmap_buffer(journal_t *journal, struct buffer_head *bh)
 	if (!buffer_jbd(bh))
 		goto zap_buffer_unlocked;
 
+	/* OK, we have data buffer in journaled mode */
 	spin_lock(&journal->j_state_lock);
 	jbd_lock_bh_state(bh);
 	spin_lock(&journal->j_list_lock);
@@ -1886,15 +1751,6 @@ static int journal_unmap_buffer(journal_t *journal, struct buffer_head *bh)
 		}
 	} else if (transaction == journal->j_committing_transaction) {
 		JBUFFER_TRACE(jh, "on committing transaction");
-		if (jh->b_jlist == BJ_Locked) {
-			/*
-			 * The buffer is on the committing transaction's locked
-			 * list.  We have the buffer locked, so I/O has
-			 * completed.  So we can nail the buffer now.
-			 */
-			may_free = __dispose_buffer(jh, transaction);
-			goto zap_buffer;
-		}
 		/*
 		 * If it is committing, we simply cannot touch it.  We
 		 * can remove it's next_transaction pointer from the
@@ -2027,9 +1883,6 @@ void __jbd2_journal_file_buffer(struct journal_head *jh,
 		J_ASSERT_JH(jh, !jh->b_committed_data);
 		J_ASSERT_JH(jh, !jh->b_frozen_data);
 		return;
-	case BJ_SyncData:
-		list = &transaction->t_sync_datalist;
-		break;
 	case BJ_Metadata:
 		transaction->t_nr_buffers++;
 		list = &transaction->t_buffers;
@@ -2049,9 +1902,6 @@ void __jbd2_journal_file_buffer(struct journal_head *jh,
 	case BJ_Reserved:
 		list = &transaction->t_reserved_list;
 		break;
-	case BJ_Locked:
-		list =  &transaction->t_locked_list;
-		break;
 	}
 
 	__blist_add_buffer(list, jh);
@@ -2141,3 +1991,88 @@ void jbd2_journal_refile_buffer(journal_t *journal, struct journal_head *jh)
 	spin_unlock(&journal->j_list_lock);
 	__brelse(bh);
 }
+
+/*
+ * File inode in the inode list of the handle's transaction
+ */
+int jbd2_journal_file_inode(handle_t *handle, struct jbd2_inode *jinode)
+{
+	transaction_t *transaction = handle->h_transaction;
+	journal_t *journal = transaction->t_journal;
+
+	if (is_handle_aborted(handle))
+		return -EIO;
+
+	jbd_debug(4, "Adding inode %lu, tid:%d\n", jinode->i_vfs_inode->i_ino,
+			transaction->t_tid);
+
+	/*
+	 * First check whether inode isn't already on the transaction's
+	 * lists without taking the lock. Note that this check is safe
+	 * without the lock as we cannot race with somebody removing inode
+	 * from the transaction. The reason is that we remove inode from the
+	 * transaction only in journal_release_jbd_inode() and when we commit
+	 * the transaction. We are guarded from the first case by holding
+	 * a reference to the inode. We are safe against the second case
+	 * because if jinode->i_transaction == transaction, commit code
+	 * cannot touch the transaction because we hold reference to it,
+	 * and if jinode->i_next_transaction == transaction, commit code
+	 * will only file the inode where we want it.
+	 */
+	if (jinode->i_transaction == transaction ||
+	    jinode->i_next_transaction == transaction)
+		return 0;
+
+	spin_lock(&journal->j_list_lock);
+
+	if (jinode->i_transaction == transaction ||
+	    jinode->i_next_transaction == transaction)
+		goto done;
+
+	/* On some different transaction's list - should be
+	 * the committing one */
+	if (jinode->i_transaction) {
+		J_ASSERT(jinode->i_next_transaction == NULL);
+		J_ASSERT(jinode->i_transaction ==
+					journal->j_committing_transaction);
+		jinode->i_next_transaction = transaction;
+		goto done;
+	}
+	/* Not on any transaction list... */
+	J_ASSERT(!jinode->i_next_transaction);
+	jinode->i_transaction = transaction;
+	list_add(&jinode->i_list, &transaction->t_inode_list);
+done:
+	spin_unlock(&journal->j_list_lock);
+
+	return 0;
+}
+
+/*
+ * This function must be called when inode is journaled in ordered mode
+ * before truncation happens. It starts writeout of truncated part in
+ * case it is in the committing transaction so that we stand to ordered
+ * mode consistency guarantees.
+ */
+int jbd2_journal_begin_ordered_truncate(struct jbd2_inode *inode,
+					loff_t new_size)
+{
+	journal_t *journal;
+	transaction_t *commit_trans;
+	int ret = 0;
+
+	if (!inode->i_transaction && !inode->i_next_transaction)
+		goto out;
+	journal = inode->i_transaction->t_journal;
+	spin_lock(&journal->j_state_lock);
+	commit_trans = journal->j_committing_transaction;
+	spin_unlock(&journal->j_state_lock);
+	if (inode->i_transaction == commit_trans) {
+		ret = filemap_fdatawrite_range(inode->i_vfs_inode->i_mapping,
+			new_size, LLONG_MAX);
+		if (ret)
+			jbd2_journal_abort(journal, ret);
+	}
+out:
+	return ret;
+}
diff --git a/fs/jfs/jfs_debug.c b/fs/jfs/jfs_debug.c
index bf6ab19b86e..6a73de84bce 100644
--- a/fs/jfs/jfs_debug.c
+++ b/fs/jfs/jfs_debug.c
@@ -21,6 +21,7 @@
 #include <linux/ctype.h>
 #include <linux/module.h>
 #include <linux/proc_fs.h>
+#include <linux/seq_file.h>
 #include <asm/uaccess.h>
 #include "jfs_incore.h"
 #include "jfs_filsys.h"
@@ -30,29 +31,19 @@
 
 static struct proc_dir_entry *base;
 #ifdef CONFIG_JFS_DEBUG
-static int loglevel_read(char *page, char **start, off_t off,
-			 int count, int *eof, void *data)
+static int jfs_loglevel_proc_show(struct seq_file *m, void *v)
 {
-	int len;
-
-	len = sprintf(page, "%d\n", jfsloglevel);
-
-	len -= off;
-	*start = page + off;
-
-	if (len > count)
-		len = count;
-	else
-		*eof = 1;
-
-	if (len < 0)
-		len = 0;
+	seq_printf(m, "%d\n", jfsloglevel);
+	return 0;
+}
 
-	return len;
+static int jfs_loglevel_proc_open(struct inode *inode, struct file *file)
+{
+	return single_open(file, jfs_loglevel_proc_show, NULL);
 }
 
-static int loglevel_write(struct file *file, const char __user *buffer,
-			unsigned long count, void *data)
+static ssize_t jfs_loglevel_proc_write(struct file *file,
+		const char __user *buffer, size_t count, loff_t *ppos)
 {
 	char c;
 
@@ -65,22 +56,30 @@ static int loglevel_write(struct file *file, const char __user *buffer,
 	jfsloglevel = c - '0';
 	return count;
 }
+
+static const struct file_operations jfs_loglevel_proc_fops = {
+	.owner		= THIS_MODULE,
+	.open		= jfs_loglevel_proc_open,
+	.read		= seq_read,
+	.llseek		= seq_lseek,
+	.release	= single_release,
+	.write		= jfs_loglevel_proc_write,
+};
 #endif
 
 static struct {
 	const char	*name;
-	read_proc_t	*read_fn;
-	write_proc_t	*write_fn;
+	const struct file_operations *proc_fops;
 } Entries[] = {
 #ifdef CONFIG_JFS_STATISTICS
-	{ "lmstats",	jfs_lmstats_read, },
-	{ "txstats",	jfs_txstats_read, },
-	{ "xtstat",	jfs_xtstat_read, },
-	{ "mpstat",	jfs_mpstat_read, },
+	{ "lmstats",	&jfs_lmstats_proc_fops, },
+	{ "txstats",	&jfs_txstats_proc_fops, },
+	{ "xtstat",	&jfs_xtstat_proc_fops, },
+	{ "mpstat",	&jfs_mpstat_proc_fops, },
 #endif
 #ifdef CONFIG_JFS_DEBUG
-	{ "TxAnchor",	jfs_txanchor_read, },
-	{ "loglevel",	loglevel_read, loglevel_write }
+	{ "TxAnchor",	&jfs_txanchor_proc_fops, },
+	{ "loglevel",	&jfs_loglevel_proc_fops }
 #endif
 };
 #define NPROCENT	ARRAY_SIZE(Entries)
@@ -93,13 +92,8 @@ void jfs_proc_init(void)
 		return;
 	base->owner = THIS_MODULE;
 
-	for (i = 0; i < NPROCENT; i++) {
-		struct proc_dir_entry *p;
-		if ((p = create_proc_entry(Entries[i].name, 0, base))) {
-			p->read_proc = Entries[i].read_fn;
-			p->write_proc = Entries[i].write_fn;
-		}
-	}
+	for (i = 0; i < NPROCENT; i++)
+		proc_create(Entries[i].name, 0, base, Entries[i].proc_fops);
 }
 
 void jfs_proc_clean(void)
diff --git a/fs/jfs/jfs_debug.h b/fs/jfs/jfs_debug.h
index 044c1e654cc..eafd1300a00 100644
--- a/fs/jfs/jfs_debug.h
+++ b/fs/jfs/jfs_debug.h
@@ -62,7 +62,7 @@ extern void jfs_proc_clean(void);
 
 extern int jfsloglevel;
 
-extern int jfs_txanchor_read(char *, char **, off_t, int, int *, void *);
+extern const struct file_operations jfs_txanchor_proc_fops;
 
 /* information message: e.g., configuration, major event */
 #define jfs_info(fmt, arg...) do {			\
@@ -105,10 +105,10 @@ extern int jfs_txanchor_read(char *, char **, off_t, int, int *, void *);
  *	----------
  */
 #ifdef	CONFIG_JFS_STATISTICS
-extern int jfs_lmstats_read(char *, char **, off_t, int, int *, void *);
-extern int jfs_txstats_read(char *, char **, off_t, int, int *, void *);
-extern int jfs_mpstat_read(char *, char **, off_t, int, int *, void *);
-extern int jfs_xtstat_read(char *, char **, off_t, int, int *, void *);
+extern const struct file_operations jfs_lmstats_proc_fops;
+extern const struct file_operations jfs_txstats_proc_fops;
+extern const struct file_operations jfs_mpstat_proc_fops;
+extern const struct file_operations jfs_xtstat_proc_fops;
 
 #define	INCREMENT(x)		((x)++)
 #define	DECREMENT(x)		((x)--)
diff --git a/fs/jfs/jfs_dtree.h b/fs/jfs/jfs_dtree.h
index cdac2d5bafe..2545bb31723 100644
--- a/fs/jfs/jfs_dtree.h
+++ b/fs/jfs/jfs_dtree.h
@@ -243,9 +243,6 @@ typedef union {
 #define JFS_REMOVE 3
 #define JFS_RENAME 4
 
-#define DIRENTSIZ(namlen) \
-    ( (sizeof(struct dirent) - 2*(JFS_NAME_MAX+1) + 2*((namlen)+1) + 3) &~ 3 )
-
 /*
  * Maximum file offset for directories.
  */
diff --git a/fs/jfs/jfs_imap.c b/fs/jfs/jfs_imap.c
index 734ec916bea..d6363d8309d 100644
--- a/fs/jfs/jfs_imap.c
+++ b/fs/jfs/jfs_imap.c
@@ -1520,7 +1520,7 @@ int diAlloc(struct inode *pip, bool dir, struct inode *ip)
 					jfs_error(ip->i_sb,
 						  "diAlloc: can't find free bit "
 						  "in wmap");
-					return EIO;
+					return -EIO;
 				}
 
 				/* determine the inode number within the
diff --git a/fs/jfs/jfs_logmgr.c b/fs/jfs/jfs_logmgr.c
index 325a9679b95..cd2ec2988b5 100644
--- a/fs/jfs/jfs_logmgr.c
+++ b/fs/jfs/jfs_logmgr.c
@@ -69,6 +69,7 @@
 #include <linux/freezer.h>
 #include <linux/delay.h>
 #include <linux/mutex.h>
+#include <linux/seq_file.h>
 #include "jfs_incore.h"
 #include "jfs_filsys.h"
 #include "jfs_metapage.h"
@@ -2503,13 +2504,9 @@ exit:
 }
 
 #ifdef CONFIG_JFS_STATISTICS
-int jfs_lmstats_read(char *buffer, char **start, off_t offset, int length,
-		      int *eof, void *data)
+static int jfs_lmstats_proc_show(struct seq_file *m, void *v)
 {
-	int len = 0;
-	off_t begin;
-
-	len += sprintf(buffer,
+	seq_printf(m,
 		       "JFS Logmgr stats\n"
 		       "================\n"
 		       "commits = %d\n"
@@ -2522,19 +2519,19 @@ int jfs_lmstats_read(char *buffer, char **start, off_t offset, int length,
 		       lmStat.pagedone,
 		       lmStat.full_page,
 		       lmStat.partial_page);
+	return 0;
+}
 
-	begin = offset;
-	*start = buffer + begin;
-	len -= begin;
-
-	if (len > length)
-		len = length;
-	else
-		*eof = 1;
-
-	if (len < 0)
-		len = 0;
-
-	return len;
+static int jfs_lmstats_proc_open(struct inode *inode, struct file *file)
+{
+	return single_open(file, jfs_lmstats_proc_show, NULL);
 }
+
+const struct file_operations jfs_lmstats_proc_fops = {
+	.owner		= THIS_MODULE,
+	.open		= jfs_lmstats_proc_open,
+	.read		= seq_read,
+	.llseek		= seq_lseek,
+	.release	= single_release,
+};
 #endif /* CONFIG_JFS_STATISTICS */
diff --git a/fs/jfs/jfs_metapage.c b/fs/jfs/jfs_metapage.c
index d1e64f2f2fc..854ff0ec574 100644
--- a/fs/jfs/jfs_metapage.c
+++ b/fs/jfs/jfs_metapage.c
@@ -19,10 +19,12 @@
 
 #include <linux/fs.h>
 #include <linux/mm.h>
+#include <linux/module.h>
 #include <linux/bio.h>
 #include <linux/init.h>
 #include <linux/buffer_head.h>
 #include <linux/mempool.h>
+#include <linux/seq_file.h>
 #include "jfs_incore.h"
 #include "jfs_superblock.h"
 #include "jfs_filsys.h"
@@ -804,13 +806,9 @@ void __invalidate_metapages(struct inode *ip, s64 addr, int len)
 }
 
 #ifdef CONFIG_JFS_STATISTICS
-int jfs_mpstat_read(char *buffer, char **start, off_t offset, int length,
-		    int *eof, void *data)
+static int jfs_mpstat_proc_show(struct seq_file *m, void *v)
 {
-	int len = 0;
-	off_t begin;
-
-	len += sprintf(buffer,
+	seq_printf(m,
 		       "JFS Metapage statistics\n"
 		       "=======================\n"
 		       "page allocations = %d\n"
@@ -819,19 +817,19 @@ int jfs_mpstat_read(char *buffer, char **start, off_t offset, int length,
 		       mpStat.pagealloc,
 		       mpStat.pagefree,
 		       mpStat.lockwait);
+	return 0;
+}
 
-	begin = offset;
-	*start = buffer + begin;
-	len -= begin;
-
-	if (len > length)
-		len = length;
-	else
-		*eof = 1;
-
-	if (len < 0)
-		len = 0;
-
-	return len;
+static int jfs_mpstat_proc_open(struct inode *inode, struct file *file)
+{
+	return single_open(file, jfs_mpstat_proc_show, NULL);
 }
+
+const struct file_operations jfs_mpstat_proc_fops = {
+	.owner		= THIS_MODULE,
+	.open		= jfs_mpstat_proc_open,
+	.read		= seq_read,
+	.llseek		= seq_lseek,
+	.release	= single_release,
+};
 #endif
diff --git a/fs/jfs/jfs_txnmgr.c b/fs/jfs/jfs_txnmgr.c
index e7c60ae6b5b..f26e4d03ada 100644
--- a/fs/jfs/jfs_txnmgr.c
+++ b/fs/jfs/jfs_txnmgr.c
@@ -49,6 +49,7 @@
 #include <linux/module.h>
 #include <linux/moduleparam.h>
 #include <linux/kthread.h>
+#include <linux/seq_file.h>
 #include "jfs_incore.h"
 #include "jfs_inode.h"
 #include "jfs_filsys.h"
@@ -3009,11 +3010,8 @@ int jfs_sync(void *arg)
 }
 
 #if defined(CONFIG_PROC_FS) && defined(CONFIG_JFS_DEBUG)
-int jfs_txanchor_read(char *buffer, char **start, off_t offset, int length,
-		      int *eof, void *data)
+static int jfs_txanchor_proc_show(struct seq_file *m, void *v)
 {
-	int len = 0;
-	off_t begin;
 	char *freewait;
 	char *freelockwait;
 	char *lowlockwait;
@@ -3025,7 +3023,7 @@ int jfs_txanchor_read(char *buffer, char **start, off_t offset, int length,
 	lowlockwait =
 	    waitqueue_active(&TxAnchor.lowlockwait) ? "active" : "empty";
 
-	len += sprintf(buffer,
+	seq_printf(m,
 		       "JFS TxAnchor\n"
 		       "============\n"
 		       "freetid = %d\n"
@@ -3044,31 +3042,27 @@ int jfs_txanchor_read(char *buffer, char **start, off_t offset, int length,
 		       TxAnchor.tlocksInUse,
 		       jfs_tlocks_low,
 		       list_empty(&TxAnchor.unlock_queue) ? "" : "not ");
+	return 0;
+}
 
-	begin = offset;
-	*start = buffer + begin;
-	len -= begin;
-
-	if (len > length)
-		len = length;
-	else
-		*eof = 1;
-
-	if (len < 0)
-		len = 0;
-
-	return len;
+static int jfs_txanchor_proc_open(struct inode *inode, struct file *file)
+{
+	return single_open(file, jfs_txanchor_proc_show, NULL);
 }
+
+const struct file_operations jfs_txanchor_proc_fops = {
+	.owner		= THIS_MODULE,
+	.open		= jfs_txanchor_proc_open,
+	.read		= seq_read,
+	.llseek		= seq_lseek,
+	.release	= single_release,
+};
 #endif
 
 #if defined(CONFIG_PROC_FS) && defined(CONFIG_JFS_STATISTICS)
-int jfs_txstats_read(char *buffer, char **start, off_t offset, int length,
-		     int *eof, void *data)
+static int jfs_txstats_proc_show(struct seq_file *m, void *v)
 {
-	int len = 0;
-	off_t begin;
-
-	len += sprintf(buffer,
+	seq_printf(m,
 		       "JFS TxStats\n"
 		       "===========\n"
 		       "calls to txBegin = %d\n"
@@ -3089,19 +3083,19 @@ int jfs_txstats_read(char *buffer, char **start, off_t offset, int length,
 		       TxStat.txBeginAnon_lockslow,
 		       TxStat.txLockAlloc,
 		       TxStat.txLockAlloc_freelock);
+	return 0;
+}
 
-	begin = offset;
-	*start = buffer + begin;
-	len -= begin;
-
-	if (len > length)
-		len = length;
-	else
-		*eof = 1;
-
-	if (len < 0)
-		len = 0;
-
-	return len;
+static int jfs_txstats_proc_open(struct inode *inode, struct file *file)
+{
+	return single_open(file, jfs_txstats_proc_show, NULL);
 }
+
+const struct file_operations jfs_txstats_proc_fops = {
+	.owner		= THIS_MODULE,
+	.open		= jfs_txstats_proc_open,
+	.read		= seq_read,
+	.llseek		= seq_lseek,
+	.release	= single_release,
+};
 #endif
diff --git a/fs/jfs/jfs_xtree.c b/fs/jfs/jfs_xtree.c
index 5a61ebf2cbc..ae3acafb447 100644
--- a/fs/jfs/jfs_xtree.c
+++ b/fs/jfs/jfs_xtree.c
@@ -20,7 +20,9 @@
  */
 
 #include <linux/fs.h>
+#include <linux/module.h>
 #include <linux/quotaops.h>
+#include <linux/seq_file.h>
 #include "jfs_incore.h"
 #include "jfs_filsys.h"
 #include "jfs_metapage.h"
@@ -4134,13 +4136,9 @@ s64 xtTruncate_pmap(tid_t tid, struct inode *ip, s64 committed_size)
 }
 
 #ifdef CONFIG_JFS_STATISTICS
-int jfs_xtstat_read(char *buffer, char **start, off_t offset, int length,
-		    int *eof, void *data)
+static int jfs_xtstat_proc_show(struct seq_file *m, void *v)
 {
-	int len = 0;
-	off_t begin;
-
-	len += sprintf(buffer,
+	seq_printf(m,
 		       "JFS Xtree statistics\n"
 		       "====================\n"
 		       "searches = %d\n"
@@ -4149,19 +4147,19 @@ int jfs_xtstat_read(char *buffer, char **start, off_t offset, int length,
 		       xtStat.search,
 		       xtStat.fastSearch,
 		       xtStat.split);
+	return 0;
+}
 
-	begin = offset;
-	*start = buffer + begin;
-	len -= begin;
-
-	if (len > length)
-		len = length;
-	else
-		*eof = 1;
-
-	if (len < 0)
-		len = 0;
-
-	return len;
+static int jfs_xtstat_proc_open(struct inode *inode, struct file *file)
+{
+	return single_open(file, jfs_xtstat_proc_show, NULL);
 }
+
+const struct file_operations jfs_xtstat_proc_fops = {
+	.owner		= THIS_MODULE,
+	.open		= jfs_xtstat_proc_open,
+	.read		= seq_read,
+	.llseek		= seq_lseek,
+	.release	= single_release,
+};
 #endif
diff --git a/fs/jfs/namei.c b/fs/jfs/namei.c
index 0ba6778edaa..2aba8238681 100644
--- a/fs/jfs/namei.c
+++ b/fs/jfs/namei.c
@@ -1455,7 +1455,7 @@ static struct dentry *jfs_lookup(struct inode *dip, struct dentry *dentry, struc
 		free_UCSname(&key);
 		if (rc == -ENOENT) {
 			d_add(dentry, NULL);
-			return ERR_PTR(0);
+			return NULL;
 		} else if (rc) {
 			jfs_err("jfs_lookup: dtSearch returned %d", rc);
 			return ERR_PTR(rc);
diff --git a/fs/jfs/super.c b/fs/jfs/super.c
index 50ea6545173..0288e6d7936 100644
--- a/fs/jfs/super.c
+++ b/fs/jfs/super.c
@@ -499,7 +499,7 @@ static int jfs_fill_super(struct super_block *sb, void *data, int silent)
 	inode = jfs_iget(sb, ROOT_I);
 	if (IS_ERR(inode)) {
 		ret = PTR_ERR(inode);
-		goto out_no_root;
+		goto out_no_rw;
 	}
 	sb->s_root = d_alloc_root(inode);
 	if (!sb->s_root)
@@ -521,9 +521,8 @@ static int jfs_fill_super(struct super_block *sb, void *data, int silent)
 	return 0;
 
 out_no_root:
-	jfs_err("jfs_read_super: get root inode failed");
-	if (inode)
-		iput(inode);
+	jfs_err("jfs_read_super: get root dentry failed");
+	iput(inode);
 
 out_no_rw:
 	rc = jfs_umount(sb);
diff --git a/fs/libfs.c b/fs/libfs.c
index 892d41cb338..baeb71ee1cd 100644
--- a/fs/libfs.c
+++ b/fs/libfs.c
@@ -512,6 +512,20 @@ void simple_release_fs(struct vfsmount **mount, int *count)
 	mntput(mnt);
 }
 
+/**
+ * simple_read_from_buffer - copy data from the buffer to user space
+ * @to: the user space buffer to read to
+ * @count: the maximum number of bytes to read
+ * @ppos: the current position in the buffer
+ * @from: the buffer to read from
+ * @available: the size of the buffer
+ *
+ * The simple_read_from_buffer() function reads up to @count bytes from the
+ * buffer @from at offset @ppos into the user space address starting at @to.
+ *
+ * On success, the number of bytes read is returned and the offset @ppos is
+ * advanced by this number, or negative value is returned on error.
+ **/
 ssize_t simple_read_from_buffer(void __user *to, size_t count, loff_t *ppos,
 				const void *from, size_t available)
 {
@@ -528,6 +542,20 @@ ssize_t simple_read_from_buffer(void __user *to, size_t count, loff_t *ppos,
 	return count;
 }
 
+/**
+ * memory_read_from_buffer - copy data from the buffer
+ * @to: the kernel space buffer to read to
+ * @count: the maximum number of bytes to read
+ * @ppos: the current position in the buffer
+ * @from: the buffer to read from
+ * @available: the size of the buffer
+ *
+ * The memory_read_from_buffer() function reads up to @count bytes from the
+ * buffer @from at offset @ppos into the kernel space address starting at @to.
+ *
+ * On success, the number of bytes read is returned and the offset @ppos is
+ * advanced by this number, or negative value is returned on error.
+ **/
 ssize_t memory_read_from_buffer(void *to, size_t count, loff_t *ppos,
 				const void *from, size_t available)
 {
diff --git a/fs/lockd/clntproc.c b/fs/lockd/clntproc.c
index 5df517b81f3..1f6dc518505 100644
--- a/fs/lockd/clntproc.c
+++ b/fs/lockd/clntproc.c
@@ -224,7 +224,9 @@ void nlm_release_call(struct nlm_rqst *call)
 
 static void nlmclnt_rpc_release(void *data)
 {
+	lock_kernel();
 	nlm_release_call(data);
+	unlock_kernel();
 }
 
 static int nlm_wait_on_grace(wait_queue_head_t *queue)
@@ -430,7 +432,7 @@ nlmclnt_test(struct nlm_rqst *req, struct file_lock *fl)
 			 * Report the conflicting lock back to the application.
 			 */
 			fl->fl_start = req->a_res.lock.fl.fl_start;
-			fl->fl_end = req->a_res.lock.fl.fl_start;
+			fl->fl_end = req->a_res.lock.fl.fl_end;
 			fl->fl_type = req->a_res.lock.fl.fl_type;
 			fl->fl_pid = 0;
 			break;
@@ -710,7 +712,9 @@ static void nlmclnt_unlock_callback(struct rpc_task *task, void *data)
 die:
 	return;
  retry_rebind:
+	lock_kernel();
 	nlm_rebind_host(req->a_host);
+	unlock_kernel();
  retry_unlock:
 	rpc_restart_call(task);
 }
@@ -788,7 +792,9 @@ retry_cancel:
 	/* Don't ever retry more than 3 times */
 	if (req->a_retries++ >= NLMCLNT_MAX_RETRIES)
 		goto die;
+	lock_kernel();
 	nlm_rebind_host(req->a_host);
+	unlock_kernel();
 	rpc_restart_call(task);
 	rpc_delay(task, 30 * HZ);
 }
diff --git a/fs/lockd/svc4proc.c b/fs/lockd/svc4proc.c
index 385437e3387..2e27176ff42 100644
--- a/fs/lockd/svc4proc.c
+++ b/fs/lockd/svc4proc.c
@@ -248,7 +248,9 @@ static void nlm4svc_callback_exit(struct rpc_task *task, void *data)
 
 static void nlm4svc_callback_release(void *data)
 {
+	lock_kernel();
 	nlm_release_call(data);
+	unlock_kernel();
 }
 
 static const struct rpc_call_ops nlm4svc_callback_ops = {
diff --git a/fs/lockd/svclock.c b/fs/lockd/svclock.c
index 81aca859bfd..56a08ab9a4c 100644
--- a/fs/lockd/svclock.c
+++ b/fs/lockd/svclock.c
@@ -795,6 +795,7 @@ static void nlmsvc_grant_callback(struct rpc_task *task, void *data)
 
 	dprintk("lockd: GRANT_MSG RPC callback\n");
 
+	lock_kernel();
 	/* if the block is not on a list at this point then it has
 	 * been invalidated. Don't try to requeue it.
 	 *
@@ -804,7 +805,7 @@ static void nlmsvc_grant_callback(struct rpc_task *task, void *data)
 	 * for nlm_blocked?
 	 */
 	if (list_empty(&block->b_list))
-		return;
+		goto out;
 
 	/* Technically, we should down the file semaphore here. Since we
 	 * move the block towards the head of the queue only, no harm
@@ -818,13 +819,17 @@ static void nlmsvc_grant_callback(struct rpc_task *task, void *data)
 	}
 	nlmsvc_insert_block(block, timeout);
 	svc_wake_up(block->b_daemon);
+out:
+	unlock_kernel();
 }
 
 static void nlmsvc_grant_release(void *data)
 {
 	struct nlm_rqst		*call = data;
 
+	lock_kernel();
 	nlmsvc_release_block(call->a_block);
+	unlock_kernel();
 }
 
 static const struct rpc_call_ops nlmsvc_grant_ops = {
diff --git a/fs/lockd/svcproc.c b/fs/lockd/svcproc.c
index 88379cc6e0b..ce6952b50a7 100644
--- a/fs/lockd/svcproc.c
+++ b/fs/lockd/svcproc.c
@@ -278,7 +278,9 @@ static void nlmsvc_callback_exit(struct rpc_task *task, void *data)
 
 static void nlmsvc_callback_release(void *data)
 {
+	lock_kernel();
 	nlm_release_call(data);
+	unlock_kernel();
 }
 
 static const struct rpc_call_ops nlmsvc_callback_ops = {
diff --git a/fs/mpage.c b/fs/mpage.c
index 235e4d3873a..dbcc7af76a1 100644
--- a/fs/mpage.c
+++ b/fs/mpage.c
@@ -82,7 +82,7 @@ static void mpage_end_io_write(struct bio *bio, int err)
 	bio_put(bio);
 }
 
-static struct bio *mpage_bio_submit(int rw, struct bio *bio)
+struct bio *mpage_bio_submit(int rw, struct bio *bio)
 {
 	bio->bi_end_io = mpage_end_io_read;
 	if (rw == WRITE)
@@ -90,6 +90,7 @@ static struct bio *mpage_bio_submit(int rw, struct bio *bio)
 	submit_bio(rw, bio);
 	return NULL;
 }
+EXPORT_SYMBOL(mpage_bio_submit);
 
 static struct bio *
 mpage_alloc(struct block_device *bdev,
@@ -435,15 +436,9 @@ EXPORT_SYMBOL(mpage_readpage);
  * written, so it can intelligently allocate a suitably-sized BIO.  For now,
  * just allocate full-size (16-page) BIOs.
  */
-struct mpage_data {
-	struct bio *bio;
-	sector_t last_block_in_bio;
-	get_block_t *get_block;
-	unsigned use_writepage;
-};
 
-static int __mpage_writepage(struct page *page, struct writeback_control *wbc,
-			     void *data)
+int __mpage_writepage(struct page *page, struct writeback_control *wbc,
+		      void *data)
 {
 	struct mpage_data *mpd = data;
 	struct bio *bio = mpd->bio;
@@ -651,6 +646,7 @@ out:
 	mpd->bio = bio;
 	return ret;
 }
+EXPORT_SYMBOL(__mpage_writepage);
 
 /**
  * mpage_writepages - walk the list of dirty pages of the given address space & writepage() all of them
diff --git a/fs/msdos/namei.c b/fs/msdos/namei.c
index 05ff4f1d702..1f7f2956412 100644
--- a/fs/msdos/namei.c
+++ b/fs/msdos/namei.c
@@ -214,7 +214,7 @@ static struct dentry *msdos_lookup(struct inode *dir, struct dentry *dentry,
 
 	dentry->d_op = &msdos_dentry_operations;
 
-	lock_kernel();
+	lock_super(sb);
 	res = msdos_find(dir, dentry->d_name.name, dentry->d_name.len, &sinfo);
 	if (res == -ENOENT)
 		goto add;
@@ -232,7 +232,7 @@ add:
 	if (dentry)
 		dentry->d_op = &msdos_dentry_operations;
 out:
-	unlock_kernel();
+	unlock_super(sb);
 	if (!res)
 		return dentry;
 	return ERR_PTR(res);
@@ -286,7 +286,7 @@ static int msdos_create(struct inode *dir, struct dentry *dentry, int mode,
 	unsigned char msdos_name[MSDOS_NAME];
 	int err, is_hid;
 
-	lock_kernel();
+	lock_super(sb);
 
 	err = msdos_format_name(dentry->d_name.name, dentry->d_name.len,
 				msdos_name, &MSDOS_SB(sb)->options);
@@ -315,7 +315,7 @@ static int msdos_create(struct inode *dir, struct dentry *dentry, int mode,
 
 	d_instantiate(dentry, inode);
 out:
-	unlock_kernel();
+	unlock_super(sb);
 	if (!err)
 		err = fat_flush_inodes(sb, dir, inode);
 	return err;
@@ -324,11 +324,12 @@ out:
 /***** Remove a directory */
 static int msdos_rmdir(struct inode *dir, struct dentry *dentry)
 {
+	struct super_block *sb = dir->i_sb;
 	struct inode *inode = dentry->d_inode;
 	struct fat_slot_info sinfo;
 	int err;
 
-	lock_kernel();
+	lock_super(sb);
 	/*
 	 * Check whether the directory is not in use, then check
 	 * whether it is empty.
@@ -349,9 +350,9 @@ static int msdos_rmdir(struct inode *dir, struct dentry *dentry)
 	inode->i_ctime = CURRENT_TIME_SEC;
 	fat_detach(inode);
 out:
-	unlock_kernel();
+	unlock_super(sb);
 	if (!err)
-		err = fat_flush_inodes(inode->i_sb, dir, inode);
+		err = fat_flush_inodes(sb, dir, inode);
 
 	return err;
 }
@@ -366,7 +367,7 @@ static int msdos_mkdir(struct inode *dir, struct dentry *dentry, int mode)
 	struct timespec ts;
 	int err, is_hid, cluster;
 
-	lock_kernel();
+	lock_super(sb);
 
 	err = msdos_format_name(dentry->d_name.name, dentry->d_name.len,
 				msdos_name, &MSDOS_SB(sb)->options);
@@ -404,14 +405,14 @@ static int msdos_mkdir(struct inode *dir, struct dentry *dentry, int mode)
 
 	d_instantiate(dentry, inode);
 
-	unlock_kernel();
+	unlock_super(sb);
 	fat_flush_inodes(sb, dir, inode);
 	return 0;
 
 out_free:
 	fat_free_clusters(dir, cluster);
 out:
-	unlock_kernel();
+	unlock_super(sb);
 	return err;
 }
 
@@ -419,10 +420,11 @@ out:
 static int msdos_unlink(struct inode *dir, struct dentry *dentry)
 {
 	struct inode *inode = dentry->d_inode;
+	struct super_block *sb= inode->i_sb;
 	struct fat_slot_info sinfo;
 	int err;
 
-	lock_kernel();
+	lock_super(sb);
 	err = msdos_find(dir, dentry->d_name.name, dentry->d_name.len, &sinfo);
 	if (err)
 		goto out;
@@ -434,9 +436,9 @@ static int msdos_unlink(struct inode *dir, struct dentry *dentry)
 	inode->i_ctime = CURRENT_TIME_SEC;
 	fat_detach(inode);
 out:
-	unlock_kernel();
+	unlock_super(sb);
 	if (!err)
-		err = fat_flush_inodes(inode->i_sb, dir, inode);
+		err = fat_flush_inodes(sb, dir, inode);
 
 	return err;
 }
@@ -618,10 +620,11 @@ error_inode:
 static int msdos_rename(struct inode *old_dir, struct dentry *old_dentry,
 			struct inode *new_dir, struct dentry *new_dentry)
 {
+	struct super_block *sb = old_dir->i_sb;
 	unsigned char old_msdos_name[MSDOS_NAME], new_msdos_name[MSDOS_NAME];
 	int err, is_hid;
 
-	lock_kernel();
+	lock_super(sb);
 
 	err = msdos_format_name(old_dentry->d_name.name,
 				old_dentry->d_name.len, old_msdos_name,
@@ -640,9 +643,9 @@ static int msdos_rename(struct inode *old_dir, struct dentry *old_dentry,
 	err = do_msdos_rename(old_dir, old_msdos_name, old_dentry,
 			      new_dir, new_msdos_name, new_dentry, is_hid);
 out:
-	unlock_kernel();
+	unlock_super(sb);
 	if (!err)
-		err = fat_flush_inodes(old_dir->i_sb, old_dir, new_dir);
+		err = fat_flush_inodes(sb, old_dir, new_dir);
 	return err;
 }
 
diff --git a/fs/namespace.c b/fs/namespace.c
index 4fc302c2a0e..4f6f7635b59 100644
--- a/fs/namespace.c
+++ b/fs/namespace.c
@@ -750,7 +750,7 @@ struct proc_fs_info {
 	const char *str;
 };
 
-static void show_sb_opts(struct seq_file *m, struct super_block *sb)
+static int show_sb_opts(struct seq_file *m, struct super_block *sb)
 {
 	static const struct proc_fs_info fs_info[] = {
 		{ MS_SYNCHRONOUS, ",sync" },
@@ -764,6 +764,8 @@ static void show_sb_opts(struct seq_file *m, struct super_block *sb)
 		if (sb->s_flags & fs_infop->flag)
 			seq_puts(m, fs_infop->str);
 	}
+
+	return security_sb_show_options(m, sb);
 }
 
 static void show_mnt_opts(struct seq_file *m, struct vfsmount *mnt)
@@ -806,11 +808,14 @@ static int show_vfsmnt(struct seq_file *m, void *v)
 	seq_putc(m, ' ');
 	show_type(m, mnt->mnt_sb);
 	seq_puts(m, __mnt_is_readonly(mnt) ? " ro" : " rw");
-	show_sb_opts(m, mnt->mnt_sb);
+	err = show_sb_opts(m, mnt->mnt_sb);
+	if (err)
+		goto out;
 	show_mnt_opts(m, mnt);
 	if (mnt->mnt_sb->s_op->show_options)
 		err = mnt->mnt_sb->s_op->show_options(m, mnt);
 	seq_puts(m, " 0 0\n");
+out:
 	return err;
 }
 
@@ -865,10 +870,13 @@ static int show_mountinfo(struct seq_file *m, void *v)
 	seq_putc(m, ' ');
 	mangle(m, mnt->mnt_devname ? mnt->mnt_devname : "none");
 	seq_puts(m, sb->s_flags & MS_RDONLY ? " ro" : " rw");
-	show_sb_opts(m, sb);
+	err = show_sb_opts(m, sb);
+	if (err)
+		goto out;
 	if (sb->s_op->show_options)
 		err = sb->s_op->show_options(m, mnt);
 	seq_putc(m, '\n');
+out:
 	return err;
 }
 
diff --git a/fs/ncpfs/file.c b/fs/ncpfs/file.c
index 2b145de45b3..6a7d901f193 100644
--- a/fs/ncpfs/file.c
+++ b/fs/ncpfs/file.c
@@ -18,6 +18,7 @@
 #include <linux/slab.h>
 #include <linux/vmalloc.h>
 #include <linux/sched.h>
+#include <linux/smp_lock.h>
 
 #include <linux/ncp_fs.h>
 #include "ncplib_kernel.h"
@@ -281,9 +282,18 @@ static int ncp_release(struct inode *inode, struct file *file) {
 	return 0;
 }
 
+static loff_t ncp_remote_llseek(struct file *file, loff_t offset, int origin)
+{
+	loff_t ret;
+	lock_kernel();
+	ret = generic_file_llseek_unlocked(file, offset, origin);
+	unlock_kernel();
+	return ret;
+}
+
 const struct file_operations ncp_file_operations =
 {
-	.llseek		= remote_llseek,
+	.llseek 	= ncp_remote_llseek,
 	.read		= ncp_file_read,
 	.write		= ncp_file_write,
 	.ioctl		= ncp_ioctl,
diff --git a/fs/nfs/callback.c b/fs/nfs/callback.c
index c1e7c830062..f447f4b4476 100644
--- a/fs/nfs/callback.c
+++ b/fs/nfs/callback.c
@@ -27,7 +27,7 @@
 
 struct nfs_callback_data {
 	unsigned int users;
-	struct svc_serv *serv;
+	struct svc_rqst *rqst;
 	struct task_struct *task;
 };
 
@@ -91,21 +91,17 @@ nfs_callback_svc(void *vrqstp)
 		svc_process(rqstp);
 	}
 	unlock_kernel();
-	nfs_callback_info.task = NULL;
-	svc_exit_thread(rqstp);
 	return 0;
 }
 
 /*
- * Bring up the server process if it is not already up.
+ * Bring up the callback thread if it is not already up.
  */
 int nfs_callback_up(void)
 {
 	struct svc_serv *serv = NULL;
-	struct svc_rqst *rqstp;
 	int ret = 0;
 
-	lock_kernel();
 	mutex_lock(&nfs_callback_mutex);
 	if (nfs_callback_info.users++ || nfs_callback_info.task != NULL)
 		goto out;
@@ -121,22 +117,23 @@ int nfs_callback_up(void)
 	nfs_callback_tcpport = ret;
 	dprintk("Callback port = 0x%x\n", nfs_callback_tcpport);
 
-	rqstp = svc_prepare_thread(serv, &serv->sv_pools[0]);
-	if (IS_ERR(rqstp)) {
-		ret = PTR_ERR(rqstp);
+	nfs_callback_info.rqst = svc_prepare_thread(serv, &serv->sv_pools[0]);
+	if (IS_ERR(nfs_callback_info.rqst)) {
+		ret = PTR_ERR(nfs_callback_info.rqst);
+		nfs_callback_info.rqst = NULL;
 		goto out_err;
 	}
 
 	svc_sock_update_bufs(serv);
-	nfs_callback_info.serv = serv;
 
-	nfs_callback_info.task = kthread_run(nfs_callback_svc, rqstp,
+	nfs_callback_info.task = kthread_run(nfs_callback_svc,
+					     nfs_callback_info.rqst,
 					     "nfsv4-svc");
 	if (IS_ERR(nfs_callback_info.task)) {
 		ret = PTR_ERR(nfs_callback_info.task);
-		nfs_callback_info.serv = NULL;
+		svc_exit_thread(nfs_callback_info.rqst);
+		nfs_callback_info.rqst = NULL;
 		nfs_callback_info.task = NULL;
-		svc_exit_thread(rqstp);
 		goto out_err;
 	}
 out:
@@ -149,7 +146,6 @@ out:
 	if (serv)
 		svc_destroy(serv);
 	mutex_unlock(&nfs_callback_mutex);
-	unlock_kernel();
 	return ret;
 out_err:
 	dprintk("Couldn't create callback socket or server thread; err = %d\n",
@@ -159,17 +155,19 @@ out_err:
 }
 
 /*
- * Kill the server process if it is not already down.
+ * Kill the callback thread if it's no longer being used.
  */
 void nfs_callback_down(void)
 {
-	lock_kernel();
 	mutex_lock(&nfs_callback_mutex);
 	nfs_callback_info.users--;
-	if (nfs_callback_info.users == 0 && nfs_callback_info.task != NULL)
+	if (nfs_callback_info.users == 0 && nfs_callback_info.task != NULL) {
 		kthread_stop(nfs_callback_info.task);
+		svc_exit_thread(nfs_callback_info.rqst);
+		nfs_callback_info.rqst = NULL;
+		nfs_callback_info.task = NULL;
+	}
 	mutex_unlock(&nfs_callback_mutex);
-	unlock_kernel();
 }
 
 static int nfs_callback_authenticate(struct svc_rqst *rqstp)
diff --git a/fs/nfs/client.c b/fs/nfs/client.c
index f2a092ca69b..5ee23e7058b 100644
--- a/fs/nfs/client.c
+++ b/fs/nfs/client.c
@@ -431,14 +431,14 @@ static void nfs_init_timeout_values(struct rpc_timeout *to, int proto,
 {
 	to->to_initval = timeo * HZ / 10;
 	to->to_retries = retrans;
-	if (!to->to_retries)
-		to->to_retries = 2;
 
 	switch (proto) {
 	case XPRT_TRANSPORT_TCP:
 	case XPRT_TRANSPORT_RDMA:
+		if (to->to_retries == 0)
+			to->to_retries = NFS_DEF_TCP_RETRANS;
 		if (to->to_initval == 0)
-			to->to_initval = 60 * HZ;
+			to->to_initval = NFS_DEF_TCP_TIMEO * HZ / 10;
 		if (to->to_initval > NFS_MAX_TCP_TIMEOUT)
 			to->to_initval = NFS_MAX_TCP_TIMEOUT;
 		to->to_increment = to->to_initval;
@@ -450,14 +450,17 @@ static void nfs_init_timeout_values(struct rpc_timeout *to, int proto,
 		to->to_exponential = 0;
 		break;
 	case XPRT_TRANSPORT_UDP:
-	default:
+		if (to->to_retries == 0)
+			to->to_retries = NFS_DEF_UDP_RETRANS;
 		if (!to->to_initval)
-			to->to_initval = 11 * HZ / 10;
+			to->to_initval = NFS_DEF_UDP_TIMEO * HZ / 10;
 		if (to->to_initval > NFS_MAX_UDP_TIMEOUT)
 			to->to_initval = NFS_MAX_UDP_TIMEOUT;
 		to->to_maxval = NFS_MAX_UDP_TIMEOUT;
 		to->to_exponential = 1;
 		break;
+	default:
+		BUG();
 	}
 }
 
diff --git a/fs/nfs/dir.c b/fs/nfs/dir.c
index 58d43daec08..28a238dab23 100644
--- a/fs/nfs/dir.c
+++ b/fs/nfs/dir.c
@@ -133,13 +133,14 @@ nfs_opendir(struct inode *inode, struct file *filp)
 {
 	int res;
 
-	dfprintk(VFS, "NFS: opendir(%s/%ld)\n",
-			inode->i_sb->s_id, inode->i_ino);
+	dfprintk(FILE, "NFS: open dir(%s/%s)\n",
+			filp->f_path.dentry->d_parent->d_name.name,
+			filp->f_path.dentry->d_name.name);
+
+	nfs_inc_stats(inode, NFSIOS_VFSOPEN);
 
-	lock_kernel();
 	/* Call generic open code in order to cache credentials */
 	res = nfs_open(inode, filp);
-	unlock_kernel();
 	return res;
 }
 
@@ -204,7 +205,7 @@ int nfs_readdir_filler(nfs_readdir_descriptor_t *desc, struct page *page)
 	 * Note: assumes we have exclusive access to this mapping either
 	 *	 through inode->i_mutex or some other mechanism.
 	 */
-	if (page->index == 0 && invalidate_inode_pages2_range(inode->i_mapping, PAGE_CACHE_SIZE, -1) < 0) {
+	if (invalidate_inode_pages2_range(inode->i_mapping, page->index + 1, -1) < 0) {
 		/* Should never happen */
 		nfs_zap_mapping(inode, inode->i_mapping);
 	}
@@ -528,13 +529,11 @@ static int nfs_readdir(struct file *filp, void *dirent, filldir_t filldir)
 	struct nfs_fattr fattr;
 	long		res;
 
-	dfprintk(VFS, "NFS: readdir(%s/%s) starting at cookie %Lu\n",
+	dfprintk(FILE, "NFS: readdir(%s/%s) starting at cookie %llu\n",
 			dentry->d_parent->d_name.name, dentry->d_name.name,
 			(long long)filp->f_pos);
 	nfs_inc_stats(inode, NFSIOS_VFSGETDENTS);
 
-	lock_kernel();
-
 	/*
 	 * filp->f_pos points to the dirent entry number.
 	 * *desc->dir_cookie has the cookie for the next entry. We have
@@ -592,10 +591,9 @@ static int nfs_readdir(struct file *filp, void *dirent, filldir_t filldir)
 	}
 out:
 	nfs_unblock_sillyrename(dentry);
-	unlock_kernel();
 	if (res > 0)
 		res = 0;
-	dfprintk(VFS, "NFS: readdir(%s/%s) returns %ld\n",
+	dfprintk(FILE, "NFS: readdir(%s/%s) returns %ld\n",
 			dentry->d_parent->d_name.name, dentry->d_name.name,
 			res);
 	return res;
@@ -603,7 +601,15 @@ out:
 
 static loff_t nfs_llseek_dir(struct file *filp, loff_t offset, int origin)
 {
-	mutex_lock(&filp->f_path.dentry->d_inode->i_mutex);
+	struct dentry *dentry = filp->f_path.dentry;
+	struct inode *inode = dentry->d_inode;
+
+	dfprintk(FILE, "NFS: llseek dir(%s/%s, %lld, %d)\n",
+			dentry->d_parent->d_name.name,
+			dentry->d_name.name,
+			offset, origin);
+
+	mutex_lock(&inode->i_mutex);
 	switch (origin) {
 		case 1:
 			offset += filp->f_pos;
@@ -619,7 +625,7 @@ static loff_t nfs_llseek_dir(struct file *filp, loff_t offset, int origin)
 		nfs_file_open_context(filp)->dir_cookie = 0;
 	}
 out:
-	mutex_unlock(&filp->f_path.dentry->d_inode->i_mutex);
+	mutex_unlock(&inode->i_mutex);
 	return offset;
 }
 
@@ -629,10 +635,11 @@ out:
  */
 static int nfs_fsync_dir(struct file *filp, struct dentry *dentry, int datasync)
 {
-	dfprintk(VFS, "NFS: fsync_dir(%s/%s) datasync %d\n",
+	dfprintk(FILE, "NFS: fsync dir(%s/%s) datasync %d\n",
 			dentry->d_parent->d_name.name, dentry->d_name.name,
 			datasync);
 
+	nfs_inc_stats(dentry->d_inode, NFSIOS_VFSFSYNC);
 	return 0;
 }
 
@@ -767,7 +774,6 @@ static int nfs_lookup_revalidate(struct dentry * dentry, struct nameidata *nd)
 	struct nfs_fattr fattr;
 
 	parent = dget_parent(dentry);
-	lock_kernel();
 	dir = parent->d_inode;
 	nfs_inc_stats(dir, NFSIOS_DENTRYREVALIDATE);
 	inode = dentry->d_inode;
@@ -805,7 +811,6 @@ static int nfs_lookup_revalidate(struct dentry * dentry, struct nameidata *nd)
 
 	nfs_set_verifier(dentry, nfs_save_change_attribute(dir));
  out_valid:
-	unlock_kernel();
 	dput(parent);
 	dfprintk(LOOKUPCACHE, "NFS: %s(%s/%s) is valid\n",
 			__func__, dentry->d_parent->d_name.name,
@@ -824,7 +829,6 @@ out_zap_parent:
 		shrink_dcache_parent(dentry);
 	}
 	d_drop(dentry);
-	unlock_kernel();
 	dput(parent);
 	dfprintk(LOOKUPCACHE, "NFS: %s(%s/%s) is invalid\n",
 			__func__, dentry->d_parent->d_name.name,
@@ -858,6 +862,14 @@ static int nfs_dentry_delete(struct dentry *dentry)
 
 }
 
+static void nfs_drop_nlink(struct inode *inode)
+{
+	spin_lock(&inode->i_lock);
+	if (inode->i_nlink > 0)
+		drop_nlink(inode);
+	spin_unlock(&inode->i_lock);
+}
+
 /*
  * Called when the dentry loses inode.
  * We use it to clean up silly-renamed files.
@@ -869,10 +881,8 @@ static void nfs_dentry_iput(struct dentry *dentry, struct inode *inode)
 		NFS_I(inode)->cache_validity |= NFS_INO_INVALID_DATA;
 
 	if (dentry->d_flags & DCACHE_NFSFS_RENAMED) {
-		lock_kernel();
 		drop_nlink(inode);
 		nfs_complete_unlink(dentry, inode);
-		unlock_kernel();
 	}
 	iput(inode);
 }
@@ -903,8 +913,6 @@ static struct dentry *nfs_lookup(struct inode *dir, struct dentry * dentry, stru
 	res = ERR_PTR(-ENOMEM);
 	dentry->d_op = NFS_PROTO(dir)->dentry_ops;
 
-	lock_kernel();
-
 	/*
 	 * If we're doing an exclusive create, optimize away the lookup
 	 * but don't hash the dentry.
@@ -912,7 +920,7 @@ static struct dentry *nfs_lookup(struct inode *dir, struct dentry * dentry, stru
 	if (nfs_is_exclusive_create(dir, nd)) {
 		d_instantiate(dentry, NULL);
 		res = NULL;
-		goto out_unlock;
+		goto out;
 	}
 
 	parent = dentry->d_parent;
@@ -940,8 +948,6 @@ no_entry:
 	nfs_set_verifier(dentry, nfs_save_change_attribute(dir));
 out_unblock_sillyrename:
 	nfs_unblock_sillyrename(parent);
-out_unlock:
-	unlock_kernel();
 out:
 	return res;
 }
@@ -999,9 +1005,7 @@ static struct dentry *nfs_atomic_lookup(struct inode *dir, struct dentry *dentry
 	}
 
 	/* Open the file on the server */
-	lock_kernel();
 	res = nfs4_atomic_open(dir, dentry, nd);
-	unlock_kernel();
 	if (IS_ERR(res)) {
 		error = PTR_ERR(res);
 		switch (error) {
@@ -1063,9 +1067,7 @@ static int nfs_open_revalidate(struct dentry *dentry, struct nameidata *nd)
 	 * operations that change the directory. We therefore save the
 	 * change attribute *before* we do the RPC call.
 	 */
-	lock_kernel();
 	ret = nfs4_open_revalidate(dir, dentry, openflags, nd);
-	unlock_kernel();
 out:
 	dput(parent);
 	if (!ret)
@@ -1218,14 +1220,11 @@ static int nfs_create(struct inode *dir, struct dentry *dentry, int mode,
 	if ((nd->flags & LOOKUP_CREATE) != 0)
 		open_flags = nd->intent.open.flags;
 
-	lock_kernel();
 	error = NFS_PROTO(dir)->create(dir, dentry, &attr, open_flags, nd);
 	if (error != 0)
 		goto out_err;
-	unlock_kernel();
 	return 0;
 out_err:
-	unlock_kernel();
 	d_drop(dentry);
 	return error;
 }
@@ -1248,14 +1247,11 @@ nfs_mknod(struct inode *dir, struct dentry *dentry, int mode, dev_t rdev)
 	attr.ia_mode = mode;
 	attr.ia_valid = ATTR_MODE;
 
-	lock_kernel();
 	status = NFS_PROTO(dir)->mknod(dir, dentry, &attr, rdev);
 	if (status != 0)
 		goto out_err;
-	unlock_kernel();
 	return 0;
 out_err:
-	unlock_kernel();
 	d_drop(dentry);
 	return status;
 }
@@ -1274,15 +1270,12 @@ static int nfs_mkdir(struct inode *dir, struct dentry *dentry, int mode)
 	attr.ia_valid = ATTR_MODE;
 	attr.ia_mode = mode | S_IFDIR;
 
-	lock_kernel();
 	error = NFS_PROTO(dir)->mkdir(dir, dentry, &attr);
 	if (error != 0)
 		goto out_err;
-	unlock_kernel();
 	return 0;
 out_err:
 	d_drop(dentry);
-	unlock_kernel();
 	return error;
 }
 
@@ -1299,14 +1292,12 @@ static int nfs_rmdir(struct inode *dir, struct dentry *dentry)
 	dfprintk(VFS, "NFS: rmdir(%s/%ld), %s\n",
 			dir->i_sb->s_id, dir->i_ino, dentry->d_name.name);
 
-	lock_kernel();
 	error = NFS_PROTO(dir)->rmdir(dir, &dentry->d_name);
 	/* Ensure the VFS deletes this inode */
 	if (error == 0 && dentry->d_inode != NULL)
 		clear_nlink(dentry->d_inode);
 	else if (error == -ENOENT)
 		nfs_dentry_handle_enoent(dentry);
-	unlock_kernel();
 
 	return error;
 }
@@ -1408,7 +1399,7 @@ static int nfs_safe_remove(struct dentry *dentry)
 		error = NFS_PROTO(dir)->remove(dir, &dentry->d_name);
 		/* The VFS may want to delete this inode */
 		if (error == 0)
-			drop_nlink(inode);
+			nfs_drop_nlink(inode);
 		nfs_mark_for_revalidate(inode);
 	} else
 		error = NFS_PROTO(dir)->remove(dir, &dentry->d_name);
@@ -1431,7 +1422,6 @@ static int nfs_unlink(struct inode *dir, struct dentry *dentry)
 	dfprintk(VFS, "NFS: unlink(%s/%ld, %s)\n", dir->i_sb->s_id,
 		dir->i_ino, dentry->d_name.name);
 
-	lock_kernel();
 	spin_lock(&dcache_lock);
 	spin_lock(&dentry->d_lock);
 	if (atomic_read(&dentry->d_count) > 1) {
@@ -1440,7 +1430,6 @@ static int nfs_unlink(struct inode *dir, struct dentry *dentry)
 		/* Start asynchronous writeout of the inode */
 		write_inode_now(dentry->d_inode, 0);
 		error = nfs_sillyrename(dir, dentry);
-		unlock_kernel();
 		return error;
 	}
 	if (!d_unhashed(dentry)) {
@@ -1454,7 +1443,6 @@ static int nfs_unlink(struct inode *dir, struct dentry *dentry)
 		nfs_set_verifier(dentry, nfs_save_change_attribute(dir));
 	} else if (need_rehash)
 		d_rehash(dentry);
-	unlock_kernel();
 	return error;
 }
 
@@ -1491,13 +1479,9 @@ static int nfs_symlink(struct inode *dir, struct dentry *dentry, const char *sym
 	attr.ia_mode = S_IFLNK | S_IRWXUGO;
 	attr.ia_valid = ATTR_MODE;
 
-	lock_kernel();
-
 	page = alloc_page(GFP_HIGHUSER);
-	if (!page) {
-		unlock_kernel();
+	if (!page)
 		return -ENOMEM;
-	}
 
 	kaddr = kmap_atomic(page, KM_USER0);
 	memcpy(kaddr, symname, pathlen);
@@ -1512,7 +1496,6 @@ static int nfs_symlink(struct inode *dir, struct dentry *dentry, const char *sym
 			dentry->d_name.name, symname, error);
 		d_drop(dentry);
 		__free_page(page);
-		unlock_kernel();
 		return error;
 	}
 
@@ -1530,7 +1513,6 @@ static int nfs_symlink(struct inode *dir, struct dentry *dentry, const char *sym
 	} else
 		__free_page(page);
 
-	unlock_kernel();
 	return 0;
 }
 
@@ -1544,14 +1526,12 @@ nfs_link(struct dentry *old_dentry, struct inode *dir, struct dentry *dentry)
 		old_dentry->d_parent->d_name.name, old_dentry->d_name.name,
 		dentry->d_parent->d_name.name, dentry->d_name.name);
 
-	lock_kernel();
 	d_drop(dentry);
 	error = NFS_PROTO(dir)->link(inode, dir, &dentry->d_name);
 	if (error == 0) {
 		atomic_inc(&inode->i_count);
 		d_add(dentry, inode);
 	}
-	unlock_kernel();
 	return error;
 }
 
@@ -1591,7 +1571,6 @@ static int nfs_rename(struct inode *old_dir, struct dentry *old_dentry,
 	 * To prevent any new references to the target during the rename,
 	 * we unhash the dentry and free the inode in advance.
 	 */
-	lock_kernel();
 	if (!d_unhashed(new_dentry)) {
 		d_drop(new_dentry);
 		rehash = new_dentry;
@@ -1635,7 +1614,7 @@ static int nfs_rename(struct inode *old_dir, struct dentry *old_dentry,
 			/* dentry still busy? */
 			goto out;
 	} else
-		drop_nlink(new_inode);
+		nfs_drop_nlink(new_inode);
 
 go_ahead:
 	/*
@@ -1669,7 +1648,6 @@ out:
 	/* new dentry created? */
 	if (dentry)
 		dput(dentry);
-	unlock_kernel();
 	return error;
 }
 
@@ -1962,8 +1940,6 @@ int nfs_permission(struct inode *inode, int mask, struct nameidata *nd)
 	}
 
 force_lookup:
-	lock_kernel();
-
 	if (!NFS_PROTO(inode)->access)
 		goto out_notsup;
 
@@ -1973,7 +1949,6 @@ force_lookup:
 		put_rpccred(cred);
 	} else
 		res = PTR_ERR(cred);
-	unlock_kernel();
 out:
 	dfprintk(VFS, "NFS: permission(%s/%ld), mask=0x%x, res=%d\n",
 		inode->i_sb->s_id, inode->i_ino, mask, res);
@@ -1982,7 +1957,6 @@ out_notsup:
 	res = nfs_revalidate_inode(NFS_SERVER(inode), inode);
 	if (res == 0)
 		res = generic_permission(inode, mask, NULL);
-	unlock_kernel();
 	goto out;
 }
 
diff --git a/fs/nfs/direct.c b/fs/nfs/direct.c
index 4757a2b326a..08f6b040d28 100644
--- a/fs/nfs/direct.c
+++ b/fs/nfs/direct.c
@@ -890,7 +890,7 @@ ssize_t nfs_file_direct_read(struct kiocb *iocb, const struct iovec *iov,
 	count = iov_length(iov, nr_segs);
 	nfs_add_stats(mapping->host, NFSIOS_DIRECTREADBYTES, count);
 
-	dprintk("nfs: direct read(%s/%s, %zd@%Ld)\n",
+	dfprintk(FILE, "NFS: direct read(%s/%s, %zd@%Ld)\n",
 		file->f_path.dentry->d_parent->d_name.name,
 		file->f_path.dentry->d_name.name,
 		count, (long long) pos);
@@ -947,7 +947,7 @@ ssize_t nfs_file_direct_write(struct kiocb *iocb, const struct iovec *iov,
 	count = iov_length(iov, nr_segs);
 	nfs_add_stats(mapping->host, NFSIOS_DIRECTWRITTENBYTES, count);
 
-	dfprintk(VFS, "nfs: direct write(%s/%s, %zd@%Ld)\n",
+	dfprintk(FILE, "NFS: direct write(%s/%s, %zd@%Ld)\n",
 		file->f_path.dentry->d_parent->d_name.name,
 		file->f_path.dentry->d_name.name,
 		count, (long long) pos);
diff --git a/fs/nfs/file.c b/fs/nfs/file.c
index d84a3d8f32a..78460657f5c 100644
--- a/fs/nfs/file.c
+++ b/fs/nfs/file.c
@@ -50,7 +50,7 @@ static ssize_t nfs_file_read(struct kiocb *, const struct iovec *iov,
 static ssize_t nfs_file_write(struct kiocb *, const struct iovec *iov,
 				unsigned long nr_segs, loff_t pos);
 static int  nfs_file_flush(struct file *, fl_owner_t id);
-static int  nfs_fsync(struct file *, struct dentry *dentry, int datasync);
+static int  nfs_file_fsync(struct file *, struct dentry *dentry, int datasync);
 static int nfs_check_flags(int flags);
 static int nfs_lock(struct file *filp, int cmd, struct file_lock *fl);
 static int nfs_flock(struct file *filp, int cmd, struct file_lock *fl);
@@ -72,7 +72,7 @@ const struct file_operations nfs_file_operations = {
 	.open		= nfs_file_open,
 	.flush		= nfs_file_flush,
 	.release	= nfs_file_release,
-	.fsync		= nfs_fsync,
+	.fsync		= nfs_file_fsync,
 	.lock		= nfs_lock,
 	.flock		= nfs_flock,
 	.splice_read	= nfs_file_splice_read,
@@ -119,25 +119,33 @@ nfs_file_open(struct inode *inode, struct file *filp)
 {
 	int res;
 
+	dprintk("NFS: open file(%s/%s)\n",
+			filp->f_path.dentry->d_parent->d_name.name,
+			filp->f_path.dentry->d_name.name);
+
 	res = nfs_check_flags(filp->f_flags);
 	if (res)
 		return res;
 
 	nfs_inc_stats(inode, NFSIOS_VFSOPEN);
-	lock_kernel();
-	res = NFS_PROTO(inode)->file_open(inode, filp);
-	unlock_kernel();
+	res = nfs_open(inode, filp);
 	return res;
 }
 
 static int
 nfs_file_release(struct inode *inode, struct file *filp)
 {
+	struct dentry *dentry = filp->f_path.dentry;
+
+	dprintk("NFS: release(%s/%s)\n",
+			dentry->d_parent->d_name.name,
+			dentry->d_name.name);
+
 	/* Ensure that dirty pages are flushed out with the right creds */
 	if (filp->f_mode & FMODE_WRITE)
-		nfs_wb_all(filp->f_path.dentry->d_inode);
+		nfs_wb_all(dentry->d_inode);
 	nfs_inc_stats(inode, NFSIOS_VFSRELEASE);
-	return NFS_PROTO(inode)->file_release(inode, filp);
+	return nfs_release(inode, filp);
 }
 
 /**
@@ -170,6 +178,13 @@ force_reval:
 
 static loff_t nfs_file_llseek(struct file *filp, loff_t offset, int origin)
 {
+	loff_t loff;
+
+	dprintk("NFS: llseek file(%s/%s, %lld, %d)\n",
+			filp->f_path.dentry->d_parent->d_name.name,
+			filp->f_path.dentry->d_name.name,
+			offset, origin);
+
 	/* origin == SEEK_END => we must revalidate the cached file length */
 	if (origin == SEEK_END) {
 		struct inode *inode = filp->f_mapping->host;
@@ -177,11 +192,14 @@ static loff_t nfs_file_llseek(struct file *filp, loff_t offset, int origin)
 		if (retval < 0)
 			return (loff_t)retval;
 	}
-	return remote_llseek(filp, offset, origin);
+	lock_kernel();	/* BKL needed? */
+	loff = generic_file_llseek_unlocked(filp, offset, origin);
+	unlock_kernel();
+	return loff;
 }
 
 /*
- * Helper for nfs_file_flush() and nfs_fsync()
+ * Helper for nfs_file_flush() and nfs_file_fsync()
  *
  * Notice that it clears the NFS_CONTEXT_ERROR_WRITE before synching to
  * disk, but it retrieves and clears ctx->error after synching, despite
@@ -207,16 +225,18 @@ static int nfs_do_fsync(struct nfs_open_context *ctx, struct inode *inode)
 
 /*
  * Flush all dirty pages, and check for write errors.
- *
  */
 static int
 nfs_file_flush(struct file *file, fl_owner_t id)
 {
 	struct nfs_open_context *ctx = nfs_file_open_context(file);
-	struct inode	*inode = file->f_path.dentry->d_inode;
+	struct dentry	*dentry = file->f_path.dentry;
+	struct inode	*inode = dentry->d_inode;
 	int		status;
 
-	dfprintk(VFS, "nfs: flush(%s/%ld)\n", inode->i_sb->s_id, inode->i_ino);
+	dprintk("NFS: flush(%s/%s)\n",
+			dentry->d_parent->d_name.name,
+			dentry->d_name.name);
 
 	if ((file->f_mode & FMODE_WRITE) == 0)
 		return 0;
@@ -241,7 +261,7 @@ nfs_file_read(struct kiocb *iocb, const struct iovec *iov,
 	if (iocb->ki_filp->f_flags & O_DIRECT)
 		return nfs_file_direct_read(iocb, iov, nr_segs, pos);
 
-	dfprintk(VFS, "nfs: read(%s/%s, %lu@%lu)\n",
+	dprintk("NFS: read(%s/%s, %lu@%lu)\n",
 		dentry->d_parent->d_name.name, dentry->d_name.name,
 		(unsigned long) count, (unsigned long) pos);
 
@@ -261,7 +281,7 @@ nfs_file_splice_read(struct file *filp, loff_t *ppos,
 	struct inode *inode = dentry->d_inode;
 	ssize_t res;
 
-	dfprintk(VFS, "nfs: splice_read(%s/%s, %lu@%Lu)\n",
+	dprintk("NFS: splice_read(%s/%s, %lu@%Lu)\n",
 		dentry->d_parent->d_name.name, dentry->d_name.name,
 		(unsigned long) count, (unsigned long long) *ppos);
 
@@ -278,7 +298,7 @@ nfs_file_mmap(struct file * file, struct vm_area_struct * vma)
 	struct inode *inode = dentry->d_inode;
 	int	status;
 
-	dfprintk(VFS, "nfs: mmap(%s/%s)\n",
+	dprintk("NFS: mmap(%s/%s)\n",
 		dentry->d_parent->d_name.name, dentry->d_name.name);
 
 	status = nfs_revalidate_mapping(inode, file->f_mapping);
@@ -296,12 +316,14 @@ nfs_file_mmap(struct file * file, struct vm_area_struct * vma)
  * whether any write errors occurred for this process.
  */
 static int
-nfs_fsync(struct file *file, struct dentry *dentry, int datasync)
+nfs_file_fsync(struct file *file, struct dentry *dentry, int datasync)
 {
 	struct nfs_open_context *ctx = nfs_file_open_context(file);
 	struct inode *inode = dentry->d_inode;
 
-	dfprintk(VFS, "nfs: fsync(%s/%ld)\n", inode->i_sb->s_id, inode->i_ino);
+	dprintk("NFS: fsync file(%s/%s) datasync %d\n",
+			dentry->d_parent->d_name.name, dentry->d_name.name,
+			datasync);
 
 	nfs_inc_stats(inode, NFSIOS_VFSFSYNC);
 	return nfs_do_fsync(ctx, inode);
@@ -324,6 +346,11 @@ static int nfs_write_begin(struct file *file, struct address_space *mapping,
 	struct page *page;
 	index = pos >> PAGE_CACHE_SHIFT;
 
+	dfprintk(PAGECACHE, "NFS: write_begin(%s/%s(%ld), %u@%lld)\n",
+		file->f_path.dentry->d_parent->d_name.name,
+		file->f_path.dentry->d_name.name,
+		mapping->host->i_ino, len, (long long) pos);
+
 	page = __grab_cache_page(mapping, index);
 	if (!page)
 		return -ENOMEM;
@@ -344,9 +371,32 @@ static int nfs_write_end(struct file *file, struct address_space *mapping,
 	unsigned offset = pos & (PAGE_CACHE_SIZE - 1);
 	int status;
 
-	lock_kernel();
+	dfprintk(PAGECACHE, "NFS: write_end(%s/%s(%ld), %u@%lld)\n",
+		file->f_path.dentry->d_parent->d_name.name,
+		file->f_path.dentry->d_name.name,
+		mapping->host->i_ino, len, (long long) pos);
+
+	/*
+	 * Zero any uninitialised parts of the page, and then mark the page
+	 * as up to date if it turns out that we're extending the file.
+	 */
+	if (!PageUptodate(page)) {
+		unsigned pglen = nfs_page_length(page);
+		unsigned end = offset + len;
+
+		if (pglen == 0) {
+			zero_user_segments(page, 0, offset,
+					end, PAGE_CACHE_SIZE);
+			SetPageUptodate(page);
+		} else if (end >= pglen) {
+			zero_user_segment(page, end, PAGE_CACHE_SIZE);
+			if (offset == 0)
+				SetPageUptodate(page);
+		} else
+			zero_user_segment(page, pglen, PAGE_CACHE_SIZE);
+	}
+
 	status = nfs_updatepage(file, page, offset, copied);
-	unlock_kernel();
 
 	unlock_page(page);
 	page_cache_release(page);
@@ -358,6 +408,8 @@ static int nfs_write_end(struct file *file, struct address_space *mapping,
 
 static void nfs_invalidate_page(struct page *page, unsigned long offset)
 {
+	dfprintk(PAGECACHE, "NFS: invalidate_page(%p, %lu)\n", page, offset);
+
 	if (offset != 0)
 		return;
 	/* Cancel any unstarted writes on this page */
@@ -366,13 +418,20 @@ static void nfs_invalidate_page(struct page *page, unsigned long offset)
 
 static int nfs_release_page(struct page *page, gfp_t gfp)
 {
+	dfprintk(PAGECACHE, "NFS: release_page(%p)\n", page);
+
 	/* If PagePrivate() is set, then the page is not freeable */
 	return 0;
 }
 
 static int nfs_launder_page(struct page *page)
 {
-	return nfs_wb_page(page->mapping->host, page);
+	struct inode *inode = page->mapping->host;
+
+	dfprintk(PAGECACHE, "NFS: launder_page(%ld, %llu)\n",
+		inode->i_ino, (long long)page_offset(page));
+
+	return nfs_wb_page(inode, page);
 }
 
 const struct address_space_operations nfs_file_aops = {
@@ -392,13 +451,19 @@ const struct address_space_operations nfs_file_aops = {
 static int nfs_vm_page_mkwrite(struct vm_area_struct *vma, struct page *page)
 {
 	struct file *filp = vma->vm_file;
+	struct dentry *dentry = filp->f_path.dentry;
 	unsigned pagelen;
 	int ret = -EINVAL;
 	struct address_space *mapping;
 
+	dfprintk(PAGECACHE, "NFS: vm_page_mkwrite(%s/%s(%ld), offset %lld)\n",
+		dentry->d_parent->d_name.name, dentry->d_name.name,
+		filp->f_mapping->host->i_ino,
+		(long long)page_offset(page));
+
 	lock_page(page);
 	mapping = page->mapping;
-	if (mapping != vma->vm_file->f_path.dentry->d_inode->i_mapping)
+	if (mapping != dentry->d_inode->i_mapping)
 		goto out_unlock;
 
 	ret = 0;
@@ -446,9 +511,9 @@ static ssize_t nfs_file_write(struct kiocb *iocb, const struct iovec *iov,
 	if (iocb->ki_filp->f_flags & O_DIRECT)
 		return nfs_file_direct_write(iocb, iov, nr_segs, pos);
 
-	dfprintk(VFS, "nfs: write(%s/%s(%ld), %lu@%Ld)\n",
+	dprintk("NFS: write(%s/%s, %lu@%Ld)\n",
 		dentry->d_parent->d_name.name, dentry->d_name.name,
-		inode->i_ino, (unsigned long) count, (long long) pos);
+		(unsigned long) count, (long long) pos);
 
 	result = -EBUSY;
 	if (IS_SWAPFILE(inode))
@@ -582,7 +647,8 @@ static int do_setlk(struct file *filp, int cmd, struct file_lock *fl)
 	 * This makes locking act as a cache coherency point.
 	 */
 	nfs_sync_mapping(filp->f_mapping);
-	nfs_zap_caches(inode);
+	if (!nfs_have_delegation(inode, FMODE_READ))
+		nfs_zap_caches(inode);
 out:
 	return status;
 }
@@ -592,23 +658,35 @@ out:
  */
 static int nfs_lock(struct file *filp, int cmd, struct file_lock *fl)
 {
-	struct inode * inode = filp->f_mapping->host;
+	struct inode *inode = filp->f_mapping->host;
+	int ret = -ENOLCK;
 
-	dprintk("NFS: nfs_lock(f=%s/%ld, t=%x, fl=%x, r=%Ld:%Ld)\n",
-			inode->i_sb->s_id, inode->i_ino,
+	dprintk("NFS: lock(%s/%s, t=%x, fl=%x, r=%lld:%lld)\n",
+			filp->f_path.dentry->d_parent->d_name.name,
+			filp->f_path.dentry->d_name.name,
 			fl->fl_type, fl->fl_flags,
 			(long long)fl->fl_start, (long long)fl->fl_end);
+
 	nfs_inc_stats(inode, NFSIOS_VFSLOCK);
 
 	/* No mandatory locks over NFS */
 	if (__mandatory_lock(inode) && fl->fl_type != F_UNLCK)
-		return -ENOLCK;
+		goto out_err;
+
+	if (NFS_PROTO(inode)->lock_check_bounds != NULL) {
+		ret = NFS_PROTO(inode)->lock_check_bounds(fl);
+		if (ret < 0)
+			goto out_err;
+	}
 
 	if (IS_GETLK(cmd))
-		return do_getlk(filp, cmd, fl);
-	if (fl->fl_type == F_UNLCK)
-		return do_unlk(filp, cmd, fl);
-	return do_setlk(filp, cmd, fl);
+		ret = do_getlk(filp, cmd, fl);
+	else if (fl->fl_type == F_UNLCK)
+		ret = do_unlk(filp, cmd, fl);
+	else
+		ret = do_setlk(filp, cmd, fl);
+out_err:
+	return ret;
 }
 
 /*
@@ -616,9 +694,9 @@ static int nfs_lock(struct file *filp, int cmd, struct file_lock *fl)
  */
 static int nfs_flock(struct file *filp, int cmd, struct file_lock *fl)
 {
-	dprintk("NFS: nfs_flock(f=%s/%ld, t=%x, fl=%x)\n",
-			filp->f_path.dentry->d_inode->i_sb->s_id,
-			filp->f_path.dentry->d_inode->i_ino,
+	dprintk("NFS: flock(%s/%s, t=%x, fl=%x)\n",
+			filp->f_path.dentry->d_parent->d_name.name,
+			filp->f_path.dentry->d_name.name,
 			fl->fl_type, fl->fl_flags);
 
 	/*
@@ -641,12 +719,15 @@ static int nfs_flock(struct file *filp, int cmd, struct file_lock *fl)
 	return do_setlk(filp, cmd, fl);
 }
 
+/*
+ * There is no protocol support for leases, so we have no way to implement
+ * them correctly in the face of opens by other clients.
+ */
 static int nfs_setlease(struct file *file, long arg, struct file_lock **fl)
 {
-	/*
-	 * There is no protocol support for leases, so we have no way
-	 * to implement them correctly in the face of opens by other
-	 * clients.
-	 */
+	dprintk("NFS: setlease(%s/%s, arg=%ld)\n",
+			file->f_path.dentry->d_parent->d_name.name,
+			file->f_path.dentry->d_name.name, arg);
+
 	return -EINVAL;
 }
diff --git a/fs/nfs/inode.c b/fs/nfs/inode.c
index 596c5d8e86f..df23f987da6 100644
--- a/fs/nfs/inode.c
+++ b/fs/nfs/inode.c
@@ -57,8 +57,6 @@ static int enable_ino64 = NFS_64_BIT_INODE_NUMBERS_ENABLED;
 static void nfs_invalidate_inode(struct inode *);
 static int nfs_update_inode(struct inode *, struct nfs_fattr *);
 
-static void nfs_zap_acl_cache(struct inode *);
-
 static struct kmem_cache * nfs_inode_cachep;
 
 static inline unsigned long
@@ -167,7 +165,7 @@ void nfs_zap_mapping(struct inode *inode, struct address_space *mapping)
 	}
 }
 
-static void nfs_zap_acl_cache(struct inode *inode)
+void nfs_zap_acl_cache(struct inode *inode)
 {
 	void (*clear_acl_cache)(struct inode *);
 
@@ -347,7 +345,7 @@ out_no_inode:
 	goto out;
 }
 
-#define NFS_VALID_ATTRS (ATTR_MODE|ATTR_UID|ATTR_GID|ATTR_SIZE|ATTR_ATIME|ATTR_ATIME_SET|ATTR_MTIME|ATTR_MTIME_SET)
+#define NFS_VALID_ATTRS (ATTR_MODE|ATTR_UID|ATTR_GID|ATTR_SIZE|ATTR_ATIME|ATTR_ATIME_SET|ATTR_MTIME|ATTR_MTIME_SET|ATTR_FILE)
 
 int
 nfs_setattr(struct dentry *dentry, struct iattr *attr)
@@ -369,10 +367,9 @@ nfs_setattr(struct dentry *dentry, struct iattr *attr)
 
 	/* Optimization: if the end result is no change, don't RPC */
 	attr->ia_valid &= NFS_VALID_ATTRS;
-	if (attr->ia_valid == 0)
+	if ((attr->ia_valid & ~ATTR_FILE) == 0)
 		return 0;
 
-	lock_kernel();
 	/* Write all dirty data */
 	if (S_ISREG(inode->i_mode)) {
 		filemap_write_and_wait(inode->i_mapping);
@@ -386,11 +383,66 @@ nfs_setattr(struct dentry *dentry, struct iattr *attr)
 	error = NFS_PROTO(inode)->setattr(dentry, &fattr, attr);
 	if (error == 0)
 		nfs_refresh_inode(inode, &fattr);
-	unlock_kernel();
 	return error;
 }
 
 /**
+ * nfs_vmtruncate - unmap mappings "freed" by truncate() syscall
+ * @inode: inode of the file used
+ * @offset: file offset to start truncating
+ *
+ * This is a copy of the common vmtruncate, but with the locking
+ * corrected to take into account the fact that NFS requires
+ * inode->i_size to be updated under the inode->i_lock.
+ */
+static int nfs_vmtruncate(struct inode * inode, loff_t offset)
+{
+	if (i_size_read(inode) < offset) {
+		unsigned long limit;
+
+		limit = current->signal->rlim[RLIMIT_FSIZE].rlim_cur;
+		if (limit != RLIM_INFINITY && offset > limit)
+			goto out_sig;
+		if (offset > inode->i_sb->s_maxbytes)
+			goto out_big;
+		spin_lock(&inode->i_lock);
+		i_size_write(inode, offset);
+		spin_unlock(&inode->i_lock);
+	} else {
+		struct address_space *mapping = inode->i_mapping;
+
+		/*
+		 * truncation of in-use swapfiles is disallowed - it would
+		 * cause subsequent swapout to scribble on the now-freed
+		 * blocks.
+		 */
+		if (IS_SWAPFILE(inode))
+			return -ETXTBSY;
+		spin_lock(&inode->i_lock);
+		i_size_write(inode, offset);
+		spin_unlock(&inode->i_lock);
+
+		/*
+		 * unmap_mapping_range is called twice, first simply for
+		 * efficiency so that truncate_inode_pages does fewer
+		 * single-page unmaps.  However after this first call, and
+		 * before truncate_inode_pages finishes, it is possible for
+		 * private pages to be COWed, which remain after
+		 * truncate_inode_pages finishes, hence the second
+		 * unmap_mapping_range call must be made for correctness.
+		 */
+		unmap_mapping_range(mapping, offset + PAGE_SIZE - 1, 0, 1);
+		truncate_inode_pages(mapping, offset);
+		unmap_mapping_range(mapping, offset + PAGE_SIZE - 1, 0, 1);
+	}
+	return 0;
+out_sig:
+	send_sig(SIGXFSZ, current, 0);
+out_big:
+	return -EFBIG;
+}
+
+/**
  * nfs_setattr_update_inode - Update inode metadata after a setattr call.
  * @inode: pointer to struct inode
  * @attr: pointer to struct iattr
@@ -416,8 +468,7 @@ void nfs_setattr_update_inode(struct inode *inode, struct iattr *attr)
 	}
 	if ((attr->ia_valid & ATTR_SIZE) != 0) {
 		nfs_inc_stats(inode, NFSIOS_SETATTRTRUNC);
-		inode->i_size = attr->ia_size;
-		vmtruncate(inode, attr->ia_size);
+		nfs_vmtruncate(inode, attr->ia_size);
 	}
 }
 
@@ -647,7 +698,6 @@ __nfs_revalidate_inode(struct nfs_server *server, struct inode *inode)
 		inode->i_sb->s_id, (long long)NFS_FILEID(inode));
 
 	nfs_inc_stats(inode, NFSIOS_INODEREVALIDATE);
-	lock_kernel();
 	if (is_bad_inode(inode))
  		goto out_nowait;
 	if (NFS_STALE(inode))
@@ -696,7 +746,6 @@ __nfs_revalidate_inode(struct nfs_server *server, struct inode *inode)
 	nfs_wake_up_inode(inode);
 
  out_nowait:
-	unlock_kernel();
 	return status;
 }
 
@@ -831,9 +880,9 @@ static void nfs_wcc_update_inode(struct inode *inode, struct nfs_fattr *fattr)
 			if (S_ISDIR(inode->i_mode))
 				nfsi->cache_validity |= NFS_INO_INVALID_DATA;
 		}
-		if (inode->i_size == nfs_size_to_loff_t(fattr->pre_size) &&
+		if (i_size_read(inode) == nfs_size_to_loff_t(fattr->pre_size) &&
 		    nfsi->npages == 0)
-			inode->i_size = nfs_size_to_loff_t(fattr->size);
+			i_size_write(inode, nfs_size_to_loff_t(fattr->size));
 	}
 }
 
@@ -974,7 +1023,7 @@ int nfs_post_op_update_inode_force_wcc(struct inode *inode, struct nfs_fattr *fa
 			(fattr->valid & NFS_ATTR_WCC) == 0) {
 		memcpy(&fattr->pre_ctime, &inode->i_ctime, sizeof(fattr->pre_ctime));
 		memcpy(&fattr->pre_mtime, &inode->i_mtime, sizeof(fattr->pre_mtime));
-		fattr->pre_size = inode->i_size;
+		fattr->pre_size = i_size_read(inode);
 		fattr->valid |= NFS_ATTR_WCC;
 	}
 	return nfs_post_op_update_inode(inode, fattr);
@@ -1059,7 +1108,7 @@ static int nfs_update_inode(struct inode *inode, struct nfs_fattr *fattr)
 		/* Do we perhaps have any outstanding writes, or has
 		 * the file grown beyond our last write? */
 		if (nfsi->npages == 0 || new_isize > cur_isize) {
-			inode->i_size = new_isize;
+			i_size_write(inode, new_isize);
 			invalid |= NFS_INO_INVALID_ATTR|NFS_INO_INVALID_DATA;
 		}
 		dprintk("NFS: isize change on server for file %s/%ld\n",
diff --git a/fs/nfs/internal.h b/fs/nfs/internal.h
index 04ae867dddb..24241fcbb98 100644
--- a/fs/nfs/internal.h
+++ b/fs/nfs/internal.h
@@ -150,6 +150,7 @@ extern void nfs_clear_inode(struct inode *);
 #ifdef CONFIG_NFS_V4
 extern void nfs4_clear_inode(struct inode *);
 #endif
+void nfs_zap_acl_cache(struct inode *inode);
 
 /* super.c */
 extern struct file_system_type nfs_xdev_fs_type;
diff --git a/fs/nfs/iostat.h b/fs/nfs/iostat.h
index 6350ecbde58..a3695281003 100644
--- a/fs/nfs/iostat.h
+++ b/fs/nfs/iostat.h
@@ -5,135 +5,41 @@
  *
  *  Copyright (C) 2005, 2006 Chuck Lever <cel@netapp.com>
  *
- *  NFS client per-mount statistics provide information about the health of
- *  the NFS client and the health of each NFS mount point.  Generally these
- *  are not for detailed problem diagnosis, but simply to indicate that there
- *  is a problem.
- *
- *  These counters are not meant to be human-readable, but are meant to be
- *  integrated into system monitoring tools such as "sar" and "iostat".  As
- *  such, the counters are sampled by the tools over time, and are never
- *  zeroed after a file system is mounted.  Moving averages can be computed
- *  by the tools by taking the difference between two instantaneous samples
- *  and dividing that by the time between the samples.
  */
 
 #ifndef _NFS_IOSTAT
 #define _NFS_IOSTAT
 
-#define NFS_IOSTAT_VERS		"1.0"
-
-/*
- * NFS byte counters
- *
- * 1.  SERVER - the number of payload bytes read from or written to the
- *     server by the NFS client via an NFS READ or WRITE request.
- *
- * 2.  NORMAL - the number of bytes read or written by applications via
- *     the read(2) and write(2) system call interfaces.
- *
- * 3.  DIRECT - the number of bytes read or written from files opened
- *     with the O_DIRECT flag.
- *
- * These counters give a view of the data throughput into and out of the NFS
- * client.  Comparing the number of bytes requested by an application with the
- * number of bytes the client requests from the server can provide an
- * indication of client efficiency (per-op, cache hits, etc).
- *
- * These counters can also help characterize which access methods are in
- * use.  DIRECT by itself shows whether there is any O_DIRECT traffic.
- * NORMAL + DIRECT shows how much data is going through the system call
- * interface.  A large amount of SERVER traffic without much NORMAL or
- * DIRECT traffic shows that applications are using mapped files.
- *
- * NFS page counters
- *
- * These count the number of pages read or written via nfs_readpage(),
- * nfs_readpages(), or their write equivalents.
- */
-enum nfs_stat_bytecounters {
-	NFSIOS_NORMALREADBYTES = 0,
-	NFSIOS_NORMALWRITTENBYTES,
-	NFSIOS_DIRECTREADBYTES,
-	NFSIOS_DIRECTWRITTENBYTES,
-	NFSIOS_SERVERREADBYTES,
-	NFSIOS_SERVERWRITTENBYTES,
-	NFSIOS_READPAGES,
-	NFSIOS_WRITEPAGES,
-	__NFSIOS_BYTESMAX,
-};
-
-/*
- * NFS event counters
- *
- * These counters provide a low-overhead way of monitoring client activity
- * without enabling NFS trace debugging.  The counters show the rate at
- * which VFS requests are made, and how often the client invalidates its
- * data and attribute caches.  This allows system administrators to monitor
- * such things as how close-to-open is working, and answer questions such
- * as "why are there so many GETATTR requests on the wire?"
- *
- * They also count anamolous events such as short reads and writes, silly
- * renames due to close-after-delete, and operations that change the size
- * of a file (such operations can often be the source of data corruption
- * if applications aren't using file locking properly).
- */
-enum nfs_stat_eventcounters {
-	NFSIOS_INODEREVALIDATE = 0,
-	NFSIOS_DENTRYREVALIDATE,
-	NFSIOS_DATAINVALIDATE,
-	NFSIOS_ATTRINVALIDATE,
-	NFSIOS_VFSOPEN,
-	NFSIOS_VFSLOOKUP,
-	NFSIOS_VFSACCESS,
-	NFSIOS_VFSUPDATEPAGE,
-	NFSIOS_VFSREADPAGE,
-	NFSIOS_VFSREADPAGES,
-	NFSIOS_VFSWRITEPAGE,
-	NFSIOS_VFSWRITEPAGES,
-	NFSIOS_VFSGETDENTS,
-	NFSIOS_VFSSETATTR,
-	NFSIOS_VFSFLUSH,
-	NFSIOS_VFSFSYNC,
-	NFSIOS_VFSLOCK,
-	NFSIOS_VFSRELEASE,
-	NFSIOS_CONGESTIONWAIT,
-	NFSIOS_SETATTRTRUNC,
-	NFSIOS_EXTENDWRITE,
-	NFSIOS_SILLYRENAME,
-	NFSIOS_SHORTREAD,
-	NFSIOS_SHORTWRITE,
-	NFSIOS_DELAY,
-	__NFSIOS_COUNTSMAX,
-};
-
-#ifdef __KERNEL__
-
 #include <linux/percpu.h>
 #include <linux/cache.h>
+#include <linux/nfs_iostat.h>
 
 struct nfs_iostats {
 	unsigned long long	bytes[__NFSIOS_BYTESMAX];
 	unsigned long		events[__NFSIOS_COUNTSMAX];
 } ____cacheline_aligned;
 
-static inline void nfs_inc_server_stats(struct nfs_server *server, enum nfs_stat_eventcounters stat)
+static inline void nfs_inc_server_stats(const struct nfs_server *server,
+					enum nfs_stat_eventcounters stat)
 {
 	struct nfs_iostats *iostats;
 	int cpu;
 
 	cpu = get_cpu();
 	iostats = per_cpu_ptr(server->io_stats, cpu);
-	iostats->events[stat] ++;
+	iostats->events[stat]++;
 	put_cpu_no_resched();
 }
 
-static inline void nfs_inc_stats(struct inode *inode, enum nfs_stat_eventcounters stat)
+static inline void nfs_inc_stats(const struct inode *inode,
+				 enum nfs_stat_eventcounters stat)
 {
 	nfs_inc_server_stats(NFS_SERVER(inode), stat);
 }
 
-static inline void nfs_add_server_stats(struct nfs_server *server, enum nfs_stat_bytecounters stat, unsigned long addend)
+static inline void nfs_add_server_stats(const struct nfs_server *server,
+					enum nfs_stat_bytecounters stat,
+					unsigned long addend)
 {
 	struct nfs_iostats *iostats;
 	int cpu;
@@ -144,7 +50,9 @@ static inline void nfs_add_server_stats(struct nfs_server *server, enum nfs_stat
 	put_cpu_no_resched();
 }
 
-static inline void nfs_add_stats(struct inode *inode, enum nfs_stat_bytecounters stat, unsigned long addend)
+static inline void nfs_add_stats(const struct inode *inode,
+				 enum nfs_stat_bytecounters stat,
+				 unsigned long addend)
 {
 	nfs_add_server_stats(NFS_SERVER(inode), stat, addend);
 }
@@ -160,5 +68,4 @@ static inline void nfs_free_iostats(struct nfs_iostats *stats)
 		free_percpu(stats);
 }
 
-#endif
-#endif
+#endif /* _NFS_IOSTAT */
diff --git a/fs/nfs/nfs3acl.c b/fs/nfs/nfs3acl.c
index 9b7362565c0..423842f51ac 100644
--- a/fs/nfs/nfs3acl.c
+++ b/fs/nfs/nfs3acl.c
@@ -5,6 +5,8 @@
 #include <linux/posix_acl_xattr.h>
 #include <linux/nfsacl.h>
 
+#include "internal.h"
+
 #define NFSDBG_FACILITY	NFSDBG_PROC
 
 ssize_t nfs3_listxattr(struct dentry *dentry, char *buffer, size_t size)
@@ -205,6 +207,8 @@ struct posix_acl *nfs3_proc_getacl(struct inode *inode, int type)
 	status = nfs_revalidate_inode(server, inode);
 	if (status < 0)
 		return ERR_PTR(status);
+	if (NFS_I(inode)->cache_validity & NFS_INO_INVALID_ACL)
+		nfs_zap_acl_cache(inode);
 	acl = nfs3_get_cached_acl(inode, type);
 	if (acl != ERR_PTR(-EAGAIN))
 		return acl;
@@ -319,9 +323,8 @@ static int nfs3_proc_setacls(struct inode *inode, struct posix_acl *acl,
 	dprintk("NFS call setacl\n");
 	msg.rpc_proc = &server->client_acl->cl_procinfo[ACLPROC3_SETACL];
 	status = rpc_call_sync(server->client_acl, &msg, 0);
-	spin_lock(&inode->i_lock);
-	NFS_I(inode)->cache_validity |= NFS_INO_INVALID_ACCESS;
-	spin_unlock(&inode->i_lock);
+	nfs_access_zap_cache(inode);
+	nfs_zap_acl_cache(inode);
 	dprintk("NFS reply setacl: %d\n", status);
 
 	/* pages may have been allocated at the xdr layer. */
diff --git a/fs/nfs/nfs3proc.c b/fs/nfs/nfs3proc.c
index c3523ad03ed..1e750e4574a 100644
--- a/fs/nfs/nfs3proc.c
+++ b/fs/nfs/nfs3proc.c
@@ -129,6 +129,8 @@ nfs3_proc_setattr(struct dentry *dentry, struct nfs_fattr *fattr,
 	int	status;
 
 	dprintk("NFS call  setattr\n");
+	if (sattr->ia_valid & ATTR_FILE)
+		msg.rpc_cred = nfs_file_cred(sattr->ia_file);
 	nfs_fattr_init(fattr);
 	status = rpc_call_sync(NFS_CLIENT(inode), &msg, 0);
 	if (status == 0)
@@ -248,6 +250,53 @@ static int nfs3_proc_readlink(struct inode *inode, struct page *page,
 	return status;
 }
 
+struct nfs3_createdata {
+	struct rpc_message msg;
+	union {
+		struct nfs3_createargs create;
+		struct nfs3_mkdirargs mkdir;
+		struct nfs3_symlinkargs symlink;
+		struct nfs3_mknodargs mknod;
+	} arg;
+	struct nfs3_diropres res;
+	struct nfs_fh fh;
+	struct nfs_fattr fattr;
+	struct nfs_fattr dir_attr;
+};
+
+static struct nfs3_createdata *nfs3_alloc_createdata(void)
+{
+	struct nfs3_createdata *data;
+
+	data = kzalloc(sizeof(*data), GFP_KERNEL);
+	if (data != NULL) {
+		data->msg.rpc_argp = &data->arg;
+		data->msg.rpc_resp = &data->res;
+		data->res.fh = &data->fh;
+		data->res.fattr = &data->fattr;
+		data->res.dir_attr = &data->dir_attr;
+		nfs_fattr_init(data->res.fattr);
+		nfs_fattr_init(data->res.dir_attr);
+	}
+	return data;
+}
+
+static int nfs3_do_create(struct inode *dir, struct dentry *dentry, struct nfs3_createdata *data)
+{
+	int status;
+
+	status = rpc_call_sync(NFS_CLIENT(dir), &data->msg, 0);
+	nfs_post_op_update_inode(dir, data->res.dir_attr);
+	if (status == 0)
+		status = nfs_instantiate(dentry, data->res.fh, data->res.fattr);
+	return status;
+}
+
+static void nfs3_free_createdata(struct nfs3_createdata *data)
+{
+	kfree(data);
+}
+
 /*
  * Create a regular file.
  * For now, we don't implement O_EXCL.
@@ -256,70 +305,60 @@ static int
 nfs3_proc_create(struct inode *dir, struct dentry *dentry, struct iattr *sattr,
 		 int flags, struct nameidata *nd)
 {
-	struct nfs_fh		fhandle;
-	struct nfs_fattr	fattr;
-	struct nfs_fattr	dir_attr;
-	struct nfs3_createargs	arg = {
-		.fh		= NFS_FH(dir),
-		.name		= dentry->d_name.name,
-		.len		= dentry->d_name.len,
-		.sattr		= sattr,
-	};
-	struct nfs3_diropres	res = {
-		.dir_attr	= &dir_attr,
-		.fh		= &fhandle,
-		.fattr		= &fattr
-	};
-	struct rpc_message msg = {
-		.rpc_proc	= &nfs3_procedures[NFS3PROC_CREATE],
-		.rpc_argp	= &arg,
-		.rpc_resp	= &res,
-	};
+	struct nfs3_createdata *data;
 	mode_t mode = sattr->ia_mode;
-	int status;
+	int status = -ENOMEM;
 
 	dprintk("NFS call  create %s\n", dentry->d_name.name);
-	arg.createmode = NFS3_CREATE_UNCHECKED;
+
+	data = nfs3_alloc_createdata();
+	if (data == NULL)
+		goto out;
+
+	data->msg.rpc_proc = &nfs3_procedures[NFS3PROC_CREATE];
+	data->arg.create.fh = NFS_FH(dir);
+	data->arg.create.name = dentry->d_name.name;
+	data->arg.create.len = dentry->d_name.len;
+	data->arg.create.sattr = sattr;
+
+	data->arg.create.createmode = NFS3_CREATE_UNCHECKED;
 	if (flags & O_EXCL) {
-		arg.createmode  = NFS3_CREATE_EXCLUSIVE;
-		arg.verifier[0] = jiffies;
-		arg.verifier[1] = current->pid;
+		data->arg.create.createmode  = NFS3_CREATE_EXCLUSIVE;
+		data->arg.create.verifier[0] = jiffies;
+		data->arg.create.verifier[1] = current->pid;
 	}
 
 	sattr->ia_mode &= ~current->fs->umask;
 
-again:
-	nfs_fattr_init(&dir_attr);
-	nfs_fattr_init(&fattr);
-	status = rpc_call_sync(NFS_CLIENT(dir), &msg, 0);
-	nfs_refresh_inode(dir, &dir_attr);
+	for (;;) {
+		status = nfs3_do_create(dir, dentry, data);
 
-	/* If the server doesn't support the exclusive creation semantics,
-	 * try again with simple 'guarded' mode. */
-	if (status == -ENOTSUPP) {
-		switch (arg.createmode) {
+		if (status != -ENOTSUPP)
+			break;
+		/* If the server doesn't support the exclusive creation
+		 * semantics, try again with simple 'guarded' mode. */
+		switch (data->arg.create.createmode) {
 			case NFS3_CREATE_EXCLUSIVE:
-				arg.createmode = NFS3_CREATE_GUARDED;
+				data->arg.create.createmode = NFS3_CREATE_GUARDED;
 				break;
 
 			case NFS3_CREATE_GUARDED:
-				arg.createmode = NFS3_CREATE_UNCHECKED;
+				data->arg.create.createmode = NFS3_CREATE_UNCHECKED;
 				break;
 
 			case NFS3_CREATE_UNCHECKED:
 				goto out;
 		}
-		goto again;
+		nfs_fattr_init(data->res.dir_attr);
+		nfs_fattr_init(data->res.fattr);
 	}
 
-	if (status == 0)
-		status = nfs_instantiate(dentry, &fhandle, &fattr);
 	if (status != 0)
 		goto out;
 
 	/* When we created the file with exclusive semantics, make
 	 * sure we set the attributes afterwards. */
-	if (arg.createmode == NFS3_CREATE_EXCLUSIVE) {
+	if (data->arg.create.createmode == NFS3_CREATE_EXCLUSIVE) {
 		dprintk("NFS call  setattr (post-create)\n");
 
 		if (!(sattr->ia_valid & ATTR_ATIME_SET))
@@ -330,14 +369,15 @@ again:
 		/* Note: we could use a guarded setattr here, but I'm
 		 * not sure this buys us anything (and I'd have
 		 * to revamp the NFSv3 XDR code) */
-		status = nfs3_proc_setattr(dentry, &fattr, sattr);
-		nfs_post_op_update_inode(dentry->d_inode, &fattr);
+		status = nfs3_proc_setattr(dentry, data->res.fattr, sattr);
+		nfs_post_op_update_inode(dentry->d_inode, data->res.fattr);
 		dprintk("NFS reply setattr (post-create): %d\n", status);
+		if (status != 0)
+			goto out;
 	}
-	if (status != 0)
-		goto out;
 	status = nfs3_proc_set_default_acl(dir, dentry->d_inode, mode);
 out:
+	nfs3_free_createdata(data);
 	dprintk("NFS reply create: %d\n", status);
 	return status;
 }
@@ -452,40 +492,28 @@ static int
 nfs3_proc_symlink(struct inode *dir, struct dentry *dentry, struct page *page,
 		  unsigned int len, struct iattr *sattr)
 {
-	struct nfs_fh fhandle;
-	struct nfs_fattr fattr, dir_attr;
-	struct nfs3_symlinkargs	arg = {
-		.fromfh		= NFS_FH(dir),
-		.fromname	= dentry->d_name.name,
-		.fromlen	= dentry->d_name.len,
-		.pages		= &page,
-		.pathlen	= len,
-		.sattr		= sattr
-	};
-	struct nfs3_diropres	res = {
-		.dir_attr	= &dir_attr,
-		.fh		= &fhandle,
-		.fattr		= &fattr
-	};
-	struct rpc_message msg = {
-		.rpc_proc	= &nfs3_procedures[NFS3PROC_SYMLINK],
-		.rpc_argp	= &arg,
-		.rpc_resp	= &res,
-	};
-	int			status;
+	struct nfs3_createdata *data;
+	int status = -ENOMEM;
 
 	if (len > NFS3_MAXPATHLEN)
 		return -ENAMETOOLONG;
 
 	dprintk("NFS call  symlink %s\n", dentry->d_name.name);
 
-	nfs_fattr_init(&dir_attr);
-	nfs_fattr_init(&fattr);
-	status = rpc_call_sync(NFS_CLIENT(dir), &msg, 0);
-	nfs_post_op_update_inode(dir, &dir_attr);
-	if (status != 0)
+	data = nfs3_alloc_createdata();
+	if (data == NULL)
 		goto out;
-	status = nfs_instantiate(dentry, &fhandle, &fattr);
+	data->msg.rpc_proc = &nfs3_procedures[NFS3PROC_SYMLINK];
+	data->arg.symlink.fromfh = NFS_FH(dir);
+	data->arg.symlink.fromname = dentry->d_name.name;
+	data->arg.symlink.fromlen = dentry->d_name.len;
+	data->arg.symlink.pages = &page;
+	data->arg.symlink.pathlen = len;
+	data->arg.symlink.sattr = sattr;
+
+	status = nfs3_do_create(dir, dentry, data);
+
+	nfs3_free_createdata(data);
 out:
 	dprintk("NFS reply symlink: %d\n", status);
 	return status;
@@ -494,42 +522,31 @@ out:
 static int
 nfs3_proc_mkdir(struct inode *dir, struct dentry *dentry, struct iattr *sattr)
 {
-	struct nfs_fh fhandle;
-	struct nfs_fattr fattr, dir_attr;
-	struct nfs3_mkdirargs	arg = {
-		.fh		= NFS_FH(dir),
-		.name		= dentry->d_name.name,
-		.len		= dentry->d_name.len,
-		.sattr		= sattr
-	};
-	struct nfs3_diropres	res = {
-		.dir_attr	= &dir_attr,
-		.fh		= &fhandle,
-		.fattr		= &fattr
-	};
-	struct rpc_message msg = {
-		.rpc_proc	= &nfs3_procedures[NFS3PROC_MKDIR],
-		.rpc_argp	= &arg,
-		.rpc_resp	= &res,
-	};
+	struct nfs3_createdata *data;
 	int mode = sattr->ia_mode;
-	int status;
+	int status = -ENOMEM;
 
 	dprintk("NFS call  mkdir %s\n", dentry->d_name.name);
 
 	sattr->ia_mode &= ~current->fs->umask;
 
-	nfs_fattr_init(&dir_attr);
-	nfs_fattr_init(&fattr);
-	status = rpc_call_sync(NFS_CLIENT(dir), &msg, 0);
-	nfs_post_op_update_inode(dir, &dir_attr);
-	if (status != 0)
+	data = nfs3_alloc_createdata();
+	if (data == NULL)
 		goto out;
-	status = nfs_instantiate(dentry, &fhandle, &fattr);
+
+	data->msg.rpc_proc = &nfs3_procedures[NFS3PROC_MKDIR];
+	data->arg.mkdir.fh = NFS_FH(dir);
+	data->arg.mkdir.name = dentry->d_name.name;
+	data->arg.mkdir.len = dentry->d_name.len;
+	data->arg.mkdir.sattr = sattr;
+
+	status = nfs3_do_create(dir, dentry, data);
 	if (status != 0)
 		goto out;
+
 	status = nfs3_proc_set_default_acl(dir, dentry->d_inode, mode);
 out:
+	nfs3_free_createdata(data);
 	dprintk("NFS reply mkdir: %d\n", status);
 	return status;
 }
@@ -615,52 +632,50 @@ static int
 nfs3_proc_mknod(struct inode *dir, struct dentry *dentry, struct iattr *sattr,
 		dev_t rdev)
 {
-	struct nfs_fh fh;
-	struct nfs_fattr fattr, dir_attr;
-	struct nfs3_mknodargs	arg = {
-		.fh		= NFS_FH(dir),
-		.name		= dentry->d_name.name,
-		.len		= dentry->d_name.len,
-		.sattr		= sattr,
-		.rdev		= rdev
-	};
-	struct nfs3_diropres	res = {
-		.dir_attr	= &dir_attr,
-		.fh		= &fh,
-		.fattr		= &fattr
-	};
-	struct rpc_message msg = {
-		.rpc_proc	= &nfs3_procedures[NFS3PROC_MKNOD],
-		.rpc_argp	= &arg,
-		.rpc_resp	= &res,
-	};
+	struct nfs3_createdata *data;
 	mode_t mode = sattr->ia_mode;
-	int status;
-
-	switch (sattr->ia_mode & S_IFMT) {
-	case S_IFBLK:	arg.type = NF3BLK;  break;
-	case S_IFCHR:	arg.type = NF3CHR;  break;
-	case S_IFIFO:	arg.type = NF3FIFO; break;
-	case S_IFSOCK:	arg.type = NF3SOCK; break;
-	default:	return -EINVAL;
-	}
+	int status = -ENOMEM;
 
 	dprintk("NFS call  mknod %s %u:%u\n", dentry->d_name.name,
 			MAJOR(rdev), MINOR(rdev));
 
 	sattr->ia_mode &= ~current->fs->umask;
 
-	nfs_fattr_init(&dir_attr);
-	nfs_fattr_init(&fattr);
-	status = rpc_call_sync(NFS_CLIENT(dir), &msg, 0);
-	nfs_post_op_update_inode(dir, &dir_attr);
-	if (status != 0)
+	data = nfs3_alloc_createdata();
+	if (data == NULL)
 		goto out;
-	status = nfs_instantiate(dentry, &fh, &fattr);
+
+	data->msg.rpc_proc = &nfs3_procedures[NFS3PROC_MKNOD];
+	data->arg.mknod.fh = NFS_FH(dir);
+	data->arg.mknod.name = dentry->d_name.name;
+	data->arg.mknod.len = dentry->d_name.len;
+	data->arg.mknod.sattr = sattr;
+	data->arg.mknod.rdev = rdev;
+
+	switch (sattr->ia_mode & S_IFMT) {
+	case S_IFBLK:
+		data->arg.mknod.type = NF3BLK;
+		break;
+	case S_IFCHR:
+		data->arg.mknod.type = NF3CHR;
+		break;
+	case S_IFIFO:
+		data->arg.mknod.type = NF3FIFO;
+		break;
+	case S_IFSOCK:
+		data->arg.mknod.type = NF3SOCK;
+		break;
+	default:
+		status = -EINVAL;
+		goto out;
+	}
+
+	status = nfs3_do_create(dir, dentry, data);
 	if (status != 0)
 		goto out;
 	status = nfs3_proc_set_default_acl(dir, dentry->d_inode, mode);
 out:
+	nfs3_free_createdata(data);
 	dprintk("NFS reply mknod: %d\n", status);
 	return status;
 }
@@ -801,8 +816,6 @@ const struct nfs_rpc_ops nfs_v3_clientops = {
 	.write_done	= nfs3_write_done,
 	.commit_setup	= nfs3_proc_commit_setup,
 	.commit_done	= nfs3_commit_done,
-	.file_open	= nfs_open,
-	.file_release	= nfs_release,
 	.lock		= nfs3_proc_lock,
 	.clear_acl_cache = nfs3_forget_cached_acls,
 };
diff --git a/fs/nfs/nfs4proc.c b/fs/nfs/nfs4proc.c
index 1293e0acd82..c910413eaec 100644
--- a/fs/nfs/nfs4proc.c
+++ b/fs/nfs/nfs4proc.c
@@ -451,9 +451,7 @@ static struct nfs4_state *nfs4_try_open_cached(struct nfs4_opendata *opendata)
 		/* Save the delegation */
 		memcpy(stateid.data, delegation->stateid.data, sizeof(stateid.data));
 		rcu_read_unlock();
-		lock_kernel();
 		ret = nfs_may_open(state->inode, state->owner->so_cred, open_mode);
-		unlock_kernel();
 		if (ret != 0)
 			goto out;
 		ret = -EAGAIN;
@@ -1139,8 +1137,9 @@ static struct nfs4_state *nfs4_do_open(struct inode *dir, struct path *path, int
 	return res;
 }
 
-static int _nfs4_do_setattr(struct inode *inode, struct nfs_fattr *fattr,
-                struct iattr *sattr, struct nfs4_state *state)
+static int _nfs4_do_setattr(struct inode *inode, struct rpc_cred *cred,
+			    struct nfs_fattr *fattr, struct iattr *sattr,
+			    struct nfs4_state *state)
 {
 	struct nfs_server *server = NFS_SERVER(inode);
         struct nfs_setattrargs  arg = {
@@ -1154,9 +1153,10 @@ static int _nfs4_do_setattr(struct inode *inode, struct nfs_fattr *fattr,
 		.server		= server,
         };
         struct rpc_message msg = {
-                .rpc_proc       = &nfs4_procedures[NFSPROC4_CLNT_SETATTR],
-                .rpc_argp       = &arg,
-                .rpc_resp       = &res,
+		.rpc_proc	= &nfs4_procedures[NFSPROC4_CLNT_SETATTR],
+		.rpc_argp	= &arg,
+		.rpc_resp	= &res,
+		.rpc_cred	= cred,
         };
 	unsigned long timestamp = jiffies;
 	int status;
@@ -1166,7 +1166,6 @@ static int _nfs4_do_setattr(struct inode *inode, struct nfs_fattr *fattr,
 	if (nfs4_copy_delegation_stateid(&arg.stateid, inode)) {
 		/* Use that stateid */
 	} else if (state != NULL) {
-		msg.rpc_cred = state->owner->so_cred;
 		nfs4_copy_stateid(&arg.stateid, state, current->files);
 	} else
 		memcpy(&arg.stateid, &zero_stateid, sizeof(arg.stateid));
@@ -1177,15 +1176,16 @@ static int _nfs4_do_setattr(struct inode *inode, struct nfs_fattr *fattr,
 	return status;
 }
 
-static int nfs4_do_setattr(struct inode *inode, struct nfs_fattr *fattr,
-                struct iattr *sattr, struct nfs4_state *state)
+static int nfs4_do_setattr(struct inode *inode, struct rpc_cred *cred,
+			   struct nfs_fattr *fattr, struct iattr *sattr,
+			   struct nfs4_state *state)
 {
 	struct nfs_server *server = NFS_SERVER(inode);
 	struct nfs4_exception exception = { };
 	int err;
 	do {
 		err = nfs4_handle_exception(server,
-				_nfs4_do_setattr(inode, fattr, sattr, state),
+				_nfs4_do_setattr(inode, cred, fattr, sattr, state),
 				&exception);
 	} while (exception.retry);
 	return err;
@@ -1647,29 +1647,25 @@ static int
 nfs4_proc_setattr(struct dentry *dentry, struct nfs_fattr *fattr,
 		  struct iattr *sattr)
 {
-	struct rpc_cred *cred;
 	struct inode *inode = dentry->d_inode;
-	struct nfs_open_context *ctx;
+	struct rpc_cred *cred = NULL;
 	struct nfs4_state *state = NULL;
 	int status;
 
 	nfs_fattr_init(fattr);
 	
-	cred = rpc_lookup_cred();
-	if (IS_ERR(cred))
-		return PTR_ERR(cred);
-
 	/* Search for an existing open(O_WRITE) file */
-	ctx = nfs_find_open_context(inode, cred, FMODE_WRITE);
-	if (ctx != NULL)
+	if (sattr->ia_valid & ATTR_FILE) {
+		struct nfs_open_context *ctx;
+
+		ctx = nfs_file_open_context(sattr->ia_file);
+		cred = ctx->cred;
 		state = ctx->state;
+	}
 
-	status = nfs4_do_setattr(inode, fattr, sattr, state);
+	status = nfs4_do_setattr(inode, cred, fattr, sattr, state);
 	if (status == 0)
 		nfs_setattr_update_inode(inode, sattr);
-	if (ctx != NULL)
-		put_nfs_open_context(ctx);
-	put_rpccred(cred);
 	return status;
 }
 
@@ -1897,17 +1893,16 @@ nfs4_proc_create(struct inode *dir, struct dentry *dentry, struct iattr *sattr,
 		goto out;
 	}
 	state = nfs4_do_open(dir, &path, flags, sattr, cred);
-	put_rpccred(cred);
 	d_drop(dentry);
 	if (IS_ERR(state)) {
 		status = PTR_ERR(state);
-		goto out;
+		goto out_putcred;
 	}
 	d_add(dentry, igrab(state->inode));
 	nfs_set_verifier(dentry, nfs_save_change_attribute(dir));
 	if (flags & O_EXCL) {
 		struct nfs_fattr fattr;
-		status = nfs4_do_setattr(state->inode, &fattr, sattr, state);
+		status = nfs4_do_setattr(state->inode, cred, &fattr, sattr, state);
 		if (status == 0)
 			nfs_setattr_update_inode(state->inode, sattr);
 		nfs_post_op_update_inode(state->inode, &fattr);
@@ -1916,6 +1911,8 @@ nfs4_proc_create(struct inode *dir, struct dentry *dentry, struct iattr *sattr,
 		status = nfs4_intent_set_file(nd, &path, state);
 	else
 		nfs4_close_sync(&path, state, flags);
+out_putcred:
+	put_rpccred(cred);
 out:
 	return status;
 }
@@ -2079,47 +2076,81 @@ static int nfs4_proc_link(struct inode *inode, struct inode *dir, struct qstr *n
 	return err;
 }
 
+struct nfs4_createdata {
+	struct rpc_message msg;
+	struct nfs4_create_arg arg;
+	struct nfs4_create_res res;
+	struct nfs_fh fh;
+	struct nfs_fattr fattr;
+	struct nfs_fattr dir_fattr;
+};
+
+static struct nfs4_createdata *nfs4_alloc_createdata(struct inode *dir,
+		struct qstr *name, struct iattr *sattr, u32 ftype)
+{
+	struct nfs4_createdata *data;
+
+	data = kzalloc(sizeof(*data), GFP_KERNEL);
+	if (data != NULL) {
+		struct nfs_server *server = NFS_SERVER(dir);
+
+		data->msg.rpc_proc = &nfs4_procedures[NFSPROC4_CLNT_CREATE];
+		data->msg.rpc_argp = &data->arg;
+		data->msg.rpc_resp = &data->res;
+		data->arg.dir_fh = NFS_FH(dir);
+		data->arg.server = server;
+		data->arg.name = name;
+		data->arg.attrs = sattr;
+		data->arg.ftype = ftype;
+		data->arg.bitmask = server->attr_bitmask;
+		data->res.server = server;
+		data->res.fh = &data->fh;
+		data->res.fattr = &data->fattr;
+		data->res.dir_fattr = &data->dir_fattr;
+		nfs_fattr_init(data->res.fattr);
+		nfs_fattr_init(data->res.dir_fattr);
+	}
+	return data;
+}
+
+static int nfs4_do_create(struct inode *dir, struct dentry *dentry, struct nfs4_createdata *data)
+{
+	int status = rpc_call_sync(NFS_CLIENT(dir), &data->msg, 0);
+	if (status == 0) {
+		update_changeattr(dir, &data->res.dir_cinfo);
+		nfs_post_op_update_inode(dir, data->res.dir_fattr);
+		status = nfs_instantiate(dentry, data->res.fh, data->res.fattr);
+	}
+	return status;
+}
+
+static void nfs4_free_createdata(struct nfs4_createdata *data)
+{
+	kfree(data);
+}
+
 static int _nfs4_proc_symlink(struct inode *dir, struct dentry *dentry,
 		struct page *page, unsigned int len, struct iattr *sattr)
 {
-	struct nfs_server *server = NFS_SERVER(dir);
-	struct nfs_fh fhandle;
-	struct nfs_fattr fattr, dir_fattr;
-	struct nfs4_create_arg arg = {
-		.dir_fh = NFS_FH(dir),
-		.server = server,
-		.name = &dentry->d_name,
-		.attrs = sattr,
-		.ftype = NF4LNK,
-		.bitmask = server->attr_bitmask,
-	};
-	struct nfs4_create_res res = {
-		.server = server,
-		.fh = &fhandle,
-		.fattr = &fattr,
-		.dir_fattr = &dir_fattr,
-	};
-	struct rpc_message msg = {
-		.rpc_proc = &nfs4_procedures[NFSPROC4_CLNT_SYMLINK],
-		.rpc_argp = &arg,
-		.rpc_resp = &res,
-	};
-	int			status;
+	struct nfs4_createdata *data;
+	int status = -ENAMETOOLONG;
 
 	if (len > NFS4_MAXPATHLEN)
-		return -ENAMETOOLONG;
+		goto out;
 
-	arg.u.symlink.pages = &page;
-	arg.u.symlink.len = len;
-	nfs_fattr_init(&fattr);
-	nfs_fattr_init(&dir_fattr);
+	status = -ENOMEM;
+	data = nfs4_alloc_createdata(dir, &dentry->d_name, sattr, NF4LNK);
+	if (data == NULL)
+		goto out;
+
+	data->msg.rpc_proc = &nfs4_procedures[NFSPROC4_CLNT_SYMLINK];
+	data->arg.u.symlink.pages = &page;
+	data->arg.u.symlink.len = len;
 	
-	status = rpc_call_sync(NFS_CLIENT(dir), &msg, 0);
-	if (!status) {
-		update_changeattr(dir, &res.dir_cinfo);
-		nfs_post_op_update_inode(dir, res.dir_fattr);
-		status = nfs_instantiate(dentry, &fhandle, &fattr);
-	}
+	status = nfs4_do_create(dir, dentry, data);
+
+	nfs4_free_createdata(data);
+out:
 	return status;
 }
 
@@ -2140,39 +2171,17 @@ static int nfs4_proc_symlink(struct inode *dir, struct dentry *dentry,
 static int _nfs4_proc_mkdir(struct inode *dir, struct dentry *dentry,
 		struct iattr *sattr)
 {
-	struct nfs_server *server = NFS_SERVER(dir);
-	struct nfs_fh fhandle;
-	struct nfs_fattr fattr, dir_fattr;
-	struct nfs4_create_arg arg = {
-		.dir_fh = NFS_FH(dir),
-		.server = server,
-		.name = &dentry->d_name,
-		.attrs = sattr,
-		.ftype = NF4DIR,
-		.bitmask = server->attr_bitmask,
-	};
-	struct nfs4_create_res res = {
-		.server = server,
-		.fh = &fhandle,
-		.fattr = &fattr,
-		.dir_fattr = &dir_fattr,
-	};
-	struct rpc_message msg = {
-		.rpc_proc = &nfs4_procedures[NFSPROC4_CLNT_CREATE],
-		.rpc_argp = &arg,
-		.rpc_resp = &res,
-	};
-	int			status;
+	struct nfs4_createdata *data;
+	int status = -ENOMEM;
 
-	nfs_fattr_init(&fattr);
-	nfs_fattr_init(&dir_fattr);
-	
-	status = rpc_call_sync(NFS_CLIENT(dir), &msg, 0);
-	if (!status) {
-		update_changeattr(dir, &res.dir_cinfo);
-		nfs_post_op_update_inode(dir, res.dir_fattr);
-		status = nfs_instantiate(dentry, &fhandle, &fattr);
-	}
+	data = nfs4_alloc_createdata(dir, &dentry->d_name, sattr, NF4DIR);
+	if (data == NULL)
+		goto out;
+
+	status = nfs4_do_create(dir, dentry, data);
+
+	nfs4_free_createdata(data);
+out:
 	return status;
 }
 
@@ -2242,56 +2251,34 @@ static int nfs4_proc_readdir(struct dentry *dentry, struct rpc_cred *cred,
 static int _nfs4_proc_mknod(struct inode *dir, struct dentry *dentry,
 		struct iattr *sattr, dev_t rdev)
 {
-	struct nfs_server *server = NFS_SERVER(dir);
-	struct nfs_fh fh;
-	struct nfs_fattr fattr, dir_fattr;
-	struct nfs4_create_arg arg = {
-		.dir_fh = NFS_FH(dir),
-		.server = server,
-		.name = &dentry->d_name,
-		.attrs = sattr,
-		.bitmask = server->attr_bitmask,
-	};
-	struct nfs4_create_res res = {
-		.server = server,
-		.fh = &fh,
-		.fattr = &fattr,
-		.dir_fattr = &dir_fattr,
-	};
-	struct rpc_message msg = {
-		.rpc_proc = &nfs4_procedures[NFSPROC4_CLNT_CREATE],
-		.rpc_argp = &arg,
-		.rpc_resp = &res,
-	};
-	int			status;
-	int                     mode = sattr->ia_mode;
-
-	nfs_fattr_init(&fattr);
-	nfs_fattr_init(&dir_fattr);
+	struct nfs4_createdata *data;
+	int mode = sattr->ia_mode;
+	int status = -ENOMEM;
 
 	BUG_ON(!(sattr->ia_valid & ATTR_MODE));
 	BUG_ON(!S_ISFIFO(mode) && !S_ISBLK(mode) && !S_ISCHR(mode) && !S_ISSOCK(mode));
+
+	data = nfs4_alloc_createdata(dir, &dentry->d_name, sattr, NF4SOCK);
+	if (data == NULL)
+		goto out;
+
 	if (S_ISFIFO(mode))
-		arg.ftype = NF4FIFO;
+		data->arg.ftype = NF4FIFO;
 	else if (S_ISBLK(mode)) {
-		arg.ftype = NF4BLK;
-		arg.u.device.specdata1 = MAJOR(rdev);
-		arg.u.device.specdata2 = MINOR(rdev);
+		data->arg.ftype = NF4BLK;
+		data->arg.u.device.specdata1 = MAJOR(rdev);
+		data->arg.u.device.specdata2 = MINOR(rdev);
 	}
 	else if (S_ISCHR(mode)) {
-		arg.ftype = NF4CHR;
-		arg.u.device.specdata1 = MAJOR(rdev);
-		arg.u.device.specdata2 = MINOR(rdev);
+		data->arg.ftype = NF4CHR;
+		data->arg.u.device.specdata1 = MAJOR(rdev);
+		data->arg.u.device.specdata2 = MINOR(rdev);
 	}
-	else
-		arg.ftype = NF4SOCK;
 	
-	status = rpc_call_sync(NFS_CLIENT(dir), &msg, 0);
-	if (status == 0) {
-		update_changeattr(dir, &res.dir_cinfo);
-		nfs_post_op_update_inode(dir, res.dir_fattr);
-		status = nfs_instantiate(dentry, &fh, &fattr);
-	}
+	status = nfs4_do_create(dir, dentry, data);
+
+	nfs4_free_createdata(data);
+out:
 	return status;
 }
 
@@ -2706,6 +2693,8 @@ static ssize_t nfs4_proc_get_acl(struct inode *inode, void *buf, size_t buflen)
 	ret = nfs_revalidate_inode(server, inode);
 	if (ret < 0)
 		return ret;
+	if (NFS_I(inode)->cache_validity & NFS_INO_INVALID_ACL)
+		nfs_zap_acl_cache(inode);
 	ret = nfs4_read_cached_acl(inode, buf, buflen);
 	if (ret != -ENOENT)
 		return ret;
@@ -2733,7 +2722,8 @@ static int __nfs4_proc_set_acl(struct inode *inode, const void *buf, size_t bufl
 	nfs_inode_return_delegation(inode);
 	buf_to_pages(buf, buflen, arg.acl_pages, &arg.acl_pgbase);
 	ret = rpc_call_sync(NFS_CLIENT(inode), &msg, 0);
-	nfs_zap_caches(inode);
+	nfs_access_zap_cache(inode);
+	nfs_zap_acl_cache(inode);
 	return ret;
 }
 
@@ -2767,8 +2757,7 @@ nfs4_async_handle_error(struct rpc_task *task, const struct nfs_server *server)
 			task->tk_status = 0;
 			return -EAGAIN;
 		case -NFS4ERR_DELAY:
-			nfs_inc_server_stats((struct nfs_server *) server,
-						NFSIOS_DELAY);
+			nfs_inc_server_stats(server, NFSIOS_DELAY);
 		case -NFS4ERR_GRACE:
 			rpc_delay(task, NFS4_POLL_RETRY_MAX);
 			task->tk_status = 0;
@@ -2933,7 +2922,7 @@ static int _nfs4_proc_setclientid_confirm(struct nfs_client *clp, struct rpc_cre
 
 int nfs4_proc_setclientid_confirm(struct nfs_client *clp, struct rpc_cred *cred)
 {
-	long timeout;
+	long timeout = 0;
 	int err;
 	do {
 		err = _nfs4_proc_setclientid_confirm(clp, cred);
@@ -3725,8 +3714,6 @@ const struct nfs_rpc_ops nfs_v4_clientops = {
 	.write_done	= nfs4_write_done,
 	.commit_setup	= nfs4_proc_commit_setup,
 	.commit_done	= nfs4_commit_done,
-	.file_open      = nfs_open,
-	.file_release   = nfs_release,
 	.lock		= nfs4_proc_lock,
 	.clear_acl_cache = nfs4_zap_acl_attr,
 };
diff --git a/fs/nfs/nfs4state.c b/fs/nfs/nfs4state.c
index 856a8934f61..401ef8b28f9 100644
--- a/fs/nfs/nfs4state.c
+++ b/fs/nfs/nfs4state.c
@@ -940,7 +940,6 @@ static int reclaimer(void *ptr)
 	allow_signal(SIGKILL);
 
 	/* Ensure exclusive access to NFSv4 state */
-	lock_kernel();
 	down_write(&clp->cl_sem);
 	/* Are there any NFS mounts out there? */
 	if (list_empty(&clp->cl_superblocks))
@@ -1000,7 +999,6 @@ restart_loop:
 	nfs_delegation_reap_unclaimed(clp);
 out:
 	up_write(&clp->cl_sem);
-	unlock_kernel();
 	if (status == -NFS4ERR_CB_PATH_DOWN)
 		nfs_handle_cb_pathdown(clp);
 	nfs4_clear_recover_bit(clp);
diff --git a/fs/nfs/nfsroot.c b/fs/nfs/nfsroot.c
index 531379d3682..46763d1cd39 100644
--- a/fs/nfs/nfsroot.c
+++ b/fs/nfs/nfsroot.c
@@ -1,6 +1,4 @@
 /*
- *  $Id: nfsroot.c,v 1.45 1998/03/07 10:44:46 mj Exp $
- *
  *  Copyright (C) 1995, 1996  Gero Kuhlmann <gero@gkminix.han.de>
  *
  *  Allow an NFS filesystem to be mounted as root. The way this works is:
@@ -297,10 +295,10 @@ static int __init root_nfs_name(char *name)
 	nfs_data.flags    = NFS_MOUNT_NONLM;	/* No lockd in nfs root yet */
 	nfs_data.rsize    = NFS_DEF_FILE_IO_SIZE;
 	nfs_data.wsize    = NFS_DEF_FILE_IO_SIZE;
-	nfs_data.acregmin = 3;
-	nfs_data.acregmax = 60;
-	nfs_data.acdirmin = 30;
-	nfs_data.acdirmax = 60;
+	nfs_data.acregmin = NFS_DEF_ACREGMIN;
+	nfs_data.acregmax = NFS_DEF_ACREGMAX;
+	nfs_data.acdirmin = NFS_DEF_ACDIRMIN;
+	nfs_data.acdirmax = NFS_DEF_ACDIRMAX;
 	strcpy(buf, NFS_ROOT);
 
 	/* Process options received from the remote server */
diff --git a/fs/nfs/proc.c b/fs/nfs/proc.c
index 03599bfe81c..4dbb84df1b6 100644
--- a/fs/nfs/proc.c
+++ b/fs/nfs/proc.c
@@ -129,6 +129,8 @@ nfs_proc_setattr(struct dentry *dentry, struct nfs_fattr *fattr,
 	sattr->ia_mode &= S_IALLUGO;
 
 	dprintk("NFS call  setattr\n");
+	if (sattr->ia_valid & ATTR_FILE)
+		msg.rpc_cred = nfs_file_cred(sattr->ia_file);
 	nfs_fattr_init(fattr);
 	status = rpc_call_sync(NFS_CLIENT(inode), &msg, 0);
 	if (status == 0)
@@ -598,6 +600,29 @@ nfs_proc_lock(struct file *filp, int cmd, struct file_lock *fl)
 	return nlmclnt_proc(NFS_SERVER(inode)->nlm_host, cmd, fl);
 }
 
+/* Helper functions for NFS lock bounds checking */
+#define NFS_LOCK32_OFFSET_MAX ((__s32)0x7fffffffUL)
+static int nfs_lock_check_bounds(const struct file_lock *fl)
+{
+	__s32 start, end;
+
+	start = (__s32)fl->fl_start;
+	if ((loff_t)start != fl->fl_start)
+		goto out_einval;
+
+	if (fl->fl_end != OFFSET_MAX) {
+		end = (__s32)fl->fl_end;
+		if ((loff_t)end != fl->fl_end)
+			goto out_einval;
+	} else
+		end = NFS_LOCK32_OFFSET_MAX;
+
+	if (start < 0 || start > end)
+		goto out_einval;
+	return 0;
+out_einval:
+	return -EINVAL;
+}
 
 const struct nfs_rpc_ops nfs_v2_clientops = {
 	.version	= 2,		       /* protocol version */
@@ -630,7 +655,6 @@ const struct nfs_rpc_ops nfs_v2_clientops = {
 	.write_setup	= nfs_proc_write_setup,
 	.write_done	= nfs_write_done,
 	.commit_setup	= nfs_proc_commit_setup,
-	.file_open	= nfs_open,
-	.file_release	= nfs_release,
 	.lock		= nfs_proc_lock,
+	.lock_check_bounds = nfs_lock_check_bounds,
 };
diff --git a/fs/nfs/super.c b/fs/nfs/super.c
index 614efeed543..1b94e3650f5 100644
--- a/fs/nfs/super.c
+++ b/fs/nfs/super.c
@@ -47,6 +47,7 @@
 #include <linux/inet.h>
 #include <linux/in6.h>
 #include <net/ipv6.h>
+#include <linux/netdevice.h>
 #include <linux/nfs_xdr.h>
 #include <linux/magic.h>
 #include <linux/parser.h>
@@ -65,7 +66,6 @@
 enum {
 	/* Mount options that take no arguments */
 	Opt_soft, Opt_hard,
-	Opt_intr, Opt_nointr,
 	Opt_posix, Opt_noposix,
 	Opt_cto, Opt_nocto,
 	Opt_ac, Opt_noac,
@@ -92,8 +92,8 @@ enum {
 	Opt_sec, Opt_proto, Opt_mountproto, Opt_mounthost,
 	Opt_addr, Opt_mountaddr, Opt_clientaddr,
 
-	/* Mount options that are ignored */
-	Opt_userspace, Opt_deprecated,
+	/* Special mount options */
+	Opt_userspace, Opt_deprecated, Opt_sloppy,
 
 	Opt_err
 };
@@ -101,10 +101,14 @@ enum {
 static match_table_t nfs_mount_option_tokens = {
 	{ Opt_userspace, "bg" },
 	{ Opt_userspace, "fg" },
+	{ Opt_userspace, "retry=%s" },
+
+	{ Opt_sloppy, "sloppy" },
+
 	{ Opt_soft, "soft" },
 	{ Opt_hard, "hard" },
-	{ Opt_intr, "intr" },
-	{ Opt_nointr, "nointr" },
+	{ Opt_deprecated, "intr" },
+	{ Opt_deprecated, "nointr" },
 	{ Opt_posix, "posix" },
 	{ Opt_noposix, "noposix" },
 	{ Opt_cto, "cto" },
@@ -136,7 +140,6 @@ static match_table_t nfs_mount_option_tokens = {
 	{ Opt_acdirmin, "acdirmin=%u" },
 	{ Opt_acdirmax, "acdirmax=%u" },
 	{ Opt_actimeo, "actimeo=%u" },
-	{ Opt_userspace, "retry=%u" },
 	{ Opt_namelen, "namlen=%u" },
 	{ Opt_mountport, "mountport=%u" },
 	{ Opt_mountvers, "mountvers=%u" },
@@ -207,6 +210,7 @@ static int nfs_xdev_get_sb(struct file_system_type *fs_type,
 		int flags, const char *dev_name, void *raw_data, struct vfsmount *mnt);
 static void nfs_kill_super(struct super_block *);
 static void nfs_put_super(struct super_block *);
+static int nfs_remount(struct super_block *sb, int *flags, char *raw_data);
 
 static struct file_system_type nfs_fs_type = {
 	.owner		= THIS_MODULE,
@@ -234,6 +238,7 @@ static const struct super_operations nfs_sops = {
 	.umount_begin	= nfs_umount_begin,
 	.show_options	= nfs_show_options,
 	.show_stats	= nfs_show_stats,
+	.remount_fs	= nfs_remount,
 };
 
 #ifdef CONFIG_NFS_V4
@@ -278,6 +283,7 @@ static const struct super_operations nfs4_sops = {
 	.umount_begin	= nfs_umount_begin,
 	.show_options	= nfs_show_options,
 	.show_stats	= nfs_show_stats,
+	.remount_fs	= nfs_remount,
 };
 #endif
 
@@ -368,8 +374,6 @@ static int nfs_statfs(struct dentry *dentry, struct kstatfs *buf)
 	};
 	int error;
 
-	lock_kernel();
-
 	error = server->nfs_client->rpc_ops->statfs(server, fh, &res);
 	if (error < 0)
 		goto out_err;
@@ -401,12 +405,10 @@ static int nfs_statfs(struct dentry *dentry, struct kstatfs *buf)
 
 	buf->f_namelen = server->namelen;
 
-	unlock_kernel();
 	return 0;
 
  out_err:
 	dprintk("%s: statfs error = %d\n", __func__, -error);
-	unlock_kernel();
 	return error;
 }
 
@@ -514,13 +516,13 @@ static void nfs_show_mount_options(struct seq_file *m, struct nfs_server *nfss,
 	if (nfss->bsize != 0)
 		seq_printf(m, ",bsize=%u", nfss->bsize);
 	seq_printf(m, ",namlen=%u", nfss->namelen);
-	if (nfss->acregmin != 3*HZ || showdefaults)
+	if (nfss->acregmin != NFS_DEF_ACREGMIN*HZ || showdefaults)
 		seq_printf(m, ",acregmin=%u", nfss->acregmin/HZ);
-	if (nfss->acregmax != 60*HZ || showdefaults)
+	if (nfss->acregmax != NFS_DEF_ACREGMAX*HZ || showdefaults)
 		seq_printf(m, ",acregmax=%u", nfss->acregmax/HZ);
-	if (nfss->acdirmin != 30*HZ || showdefaults)
+	if (nfss->acdirmin != NFS_DEF_ACDIRMIN*HZ || showdefaults)
 		seq_printf(m, ",acdirmin=%u", nfss->acdirmin/HZ);
-	if (nfss->acdirmax != 60*HZ || showdefaults)
+	if (nfss->acdirmax != NFS_DEF_ACDIRMAX*HZ || showdefaults)
 		seq_printf(m, ",acdirmax=%u", nfss->acdirmax/HZ);
 	for (nfs_infop = nfs_info; nfs_infop->flag; nfs_infop++) {
 		if (nfss->flags & nfs_infop->flag)
@@ -702,49 +704,233 @@ static int nfs_verify_server_address(struct sockaddr *addr)
 	return 0;
 }
 
+static void nfs_parse_ipv4_address(char *string, size_t str_len,
+				   struct sockaddr *sap, size_t *addr_len)
+{
+	struct sockaddr_in *sin = (struct sockaddr_in *)sap;
+	u8 *addr = (u8 *)&sin->sin_addr.s_addr;
+
+	if (str_len <= INET_ADDRSTRLEN) {
+		dfprintk(MOUNT, "NFS: parsing IPv4 address %*s\n",
+				(int)str_len, string);
+
+		sin->sin_family = AF_INET;
+		*addr_len = sizeof(*sin);
+		if (in4_pton(string, str_len, addr, '\0', NULL))
+			return;
+	}
+
+	sap->sa_family = AF_UNSPEC;
+	*addr_len = 0;
+}
+
+#define IPV6_SCOPE_DELIMITER	'%'
+
+#if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
+static void nfs_parse_ipv6_scope_id(const char *string, const size_t str_len,
+				    const char *delim,
+				    struct sockaddr_in6 *sin6)
+{
+	char *p;
+	size_t len;
+
+	if (!(ipv6_addr_type(&sin6->sin6_addr) & IPV6_ADDR_LINKLOCAL))
+		return ;
+	if (*delim != IPV6_SCOPE_DELIMITER)
+		return;
+
+	len = (string + str_len) - delim - 1;
+	p = kstrndup(delim + 1, len, GFP_KERNEL);
+	if (p) {
+		unsigned long scope_id = 0;
+		struct net_device *dev;
+
+		dev = dev_get_by_name(&init_net, p);
+		if (dev != NULL) {
+			scope_id = dev->ifindex;
+			dev_put(dev);
+		} else {
+			/* scope_id is set to zero on error */
+			strict_strtoul(p, 10, &scope_id);
+		}
+
+		kfree(p);
+		sin6->sin6_scope_id = scope_id;
+		dfprintk(MOUNT, "NFS: IPv6 scope ID = %lu\n", scope_id);
+	}
+}
+
+static void nfs_parse_ipv6_address(char *string, size_t str_len,
+				   struct sockaddr *sap, size_t *addr_len)
+{
+	struct sockaddr_in6 *sin6 = (struct sockaddr_in6 *)sap;
+	u8 *addr = (u8 *)&sin6->sin6_addr.in6_u;
+	const char *delim;
+
+	if (str_len <= INET6_ADDRSTRLEN) {
+		dfprintk(MOUNT, "NFS: parsing IPv6 address %*s\n",
+				(int)str_len, string);
+
+		sin6->sin6_family = AF_INET6;
+		*addr_len = sizeof(*sin6);
+		if (in6_pton(string, str_len, addr, IPV6_SCOPE_DELIMITER, &delim)) {
+			nfs_parse_ipv6_scope_id(string, str_len, delim, sin6);
+			return;
+		}
+	}
+
+	sap->sa_family = AF_UNSPEC;
+	*addr_len = 0;
+}
+#else
+static void nfs_parse_ipv6_address(char *string, size_t str_len,
+				   struct sockaddr *sap, size_t *addr_len)
+{
+	sap->sa_family = AF_UNSPEC;
+	*addr_len = 0;
+}
+#endif
+
 /*
- * Parse string addresses passed in via a mount option,
- * and construct a sockaddr based on the result.
+ * Construct a sockaddr based on the contents of a string that contains
+ * an IP address in presentation format.
  *
- * If address parsing fails, set the sockaddr's address
- * family to AF_UNSPEC to force nfs_verify_server_address()
- * to punt the mount.
+ * If there is a problem constructing the new sockaddr, set the address
+ * family to AF_UNSPEC.
  */
-static void nfs_parse_server_address(char *value,
-				     struct sockaddr *sap,
-				     size_t *len)
+static void nfs_parse_ip_address(char *string, size_t str_len,
+				 struct sockaddr *sap, size_t *addr_len)
 {
-	if (strchr(value, ':')) {
-		struct sockaddr_in6 *ap = (struct sockaddr_in6 *)sap;
-		u8 *addr = (u8 *)&ap->sin6_addr.in6_u;
+	unsigned int i, colons;
 
-		ap->sin6_family = AF_INET6;
-		*len = sizeof(*ap);
-		if (in6_pton(value, -1, addr, '\0', NULL))
-			return;
-	} else {
-		struct sockaddr_in *ap = (struct sockaddr_in *)sap;
-		u8 *addr = (u8 *)&ap->sin_addr.s_addr;
+	colons = 0;
+	for (i = 0; i < str_len; i++)
+		if (string[i] == ':')
+			colons++;
+
+	if (colons >= 2)
+		nfs_parse_ipv6_address(string, str_len, sap, addr_len);
+	else
+		nfs_parse_ipv4_address(string, str_len, sap, addr_len);
+}
+
+/*
+ * Sanity check the NFS transport protocol.
+ *
+ */
+static void nfs_validate_transport_protocol(struct nfs_parsed_mount_data *mnt)
+{
+	switch (mnt->nfs_server.protocol) {
+	case XPRT_TRANSPORT_UDP:
+	case XPRT_TRANSPORT_TCP:
+	case XPRT_TRANSPORT_RDMA:
+		break;
+	default:
+		mnt->nfs_server.protocol = XPRT_TRANSPORT_TCP;
+	}
+}
+
+/*
+ * For text based NFSv2/v3 mounts, the mount protocol transport default
+ * settings should depend upon the specified NFS transport.
+ */
+static void nfs_set_mount_transport_protocol(struct nfs_parsed_mount_data *mnt)
+{
+	nfs_validate_transport_protocol(mnt);
 
-		ap->sin_family = AF_INET;
-		*len = sizeof(*ap);
-		if (in4_pton(value, -1, addr, '\0', NULL))
+	if (mnt->mount_server.protocol == XPRT_TRANSPORT_UDP ||
+	    mnt->mount_server.protocol == XPRT_TRANSPORT_TCP)
 			return;
+	switch (mnt->nfs_server.protocol) {
+	case XPRT_TRANSPORT_UDP:
+		mnt->mount_server.protocol = XPRT_TRANSPORT_UDP;
+		break;
+	case XPRT_TRANSPORT_TCP:
+	case XPRT_TRANSPORT_RDMA:
+		mnt->mount_server.protocol = XPRT_TRANSPORT_TCP;
 	}
+}
 
-	sap->sa_family = AF_UNSPEC;
-	*len = 0;
+/*
+ * Parse the value of the 'sec=' option.
+ *
+ * The flavor_len setting is for v4 mounts.
+ */
+static int nfs_parse_security_flavors(char *value,
+				      struct nfs_parsed_mount_data *mnt)
+{
+	substring_t args[MAX_OPT_ARGS];
+
+	dfprintk(MOUNT, "NFS: parsing sec=%s option\n", value);
+
+	switch (match_token(value, nfs_secflavor_tokens, args)) {
+	case Opt_sec_none:
+		mnt->auth_flavor_len = 0;
+		mnt->auth_flavors[0] = RPC_AUTH_NULL;
+		break;
+	case Opt_sec_sys:
+		mnt->auth_flavor_len = 0;
+		mnt->auth_flavors[0] = RPC_AUTH_UNIX;
+		break;
+	case Opt_sec_krb5:
+		mnt->auth_flavor_len = 1;
+		mnt->auth_flavors[0] = RPC_AUTH_GSS_KRB5;
+		break;
+	case Opt_sec_krb5i:
+		mnt->auth_flavor_len = 1;
+		mnt->auth_flavors[0] = RPC_AUTH_GSS_KRB5I;
+		break;
+	case Opt_sec_krb5p:
+		mnt->auth_flavor_len = 1;
+		mnt->auth_flavors[0] = RPC_AUTH_GSS_KRB5P;
+		break;
+	case Opt_sec_lkey:
+		mnt->auth_flavor_len = 1;
+		mnt->auth_flavors[0] = RPC_AUTH_GSS_LKEY;
+		break;
+	case Opt_sec_lkeyi:
+		mnt->auth_flavor_len = 1;
+		mnt->auth_flavors[0] = RPC_AUTH_GSS_LKEYI;
+		break;
+	case Opt_sec_lkeyp:
+		mnt->auth_flavor_len = 1;
+		mnt->auth_flavors[0] = RPC_AUTH_GSS_LKEYP;
+		break;
+	case Opt_sec_spkm:
+		mnt->auth_flavor_len = 1;
+		mnt->auth_flavors[0] = RPC_AUTH_GSS_SPKM;
+		break;
+	case Opt_sec_spkmi:
+		mnt->auth_flavor_len = 1;
+		mnt->auth_flavors[0] = RPC_AUTH_GSS_SPKMI;
+		break;
+	case Opt_sec_spkmp:
+		mnt->auth_flavor_len = 1;
+		mnt->auth_flavors[0] = RPC_AUTH_GSS_SPKMP;
+		break;
+	default:
+		return 0;
+	}
+
+	return 1;
+}
+
+static void nfs_parse_invalid_value(const char *option)
+{
+	dfprintk(MOUNT, "NFS:   bad value specified for %s option\n", option);
 }
 
 /*
  * Error-check and convert a string of mount options from user space into
- * a data structure
+ * a data structure.  The whole mount string is processed; bad options are
+ * skipped as they are encountered.  If there were no errors, return 1;
+ * otherwise return 0 (zero).
  */
 static int nfs_parse_mount_options(char *raw,
 				   struct nfs_parsed_mount_data *mnt)
 {
 	char *p, *string, *secdata;
-	int rc;
+	int rc, sloppy = 0, errors = 0;
 
 	if (!raw) {
 		dfprintk(MOUNT, "NFS: mount options string was NULL.\n");
@@ -777,15 +963,16 @@ static int nfs_parse_mount_options(char *raw,
 
 		token = match_token(p, nfs_mount_option_tokens, args);
 		switch (token) {
+
+		/*
+		 * boolean options:  foo/nofoo
+		 */
 		case Opt_soft:
 			mnt->flags |= NFS_MOUNT_SOFT;
 			break;
 		case Opt_hard:
 			mnt->flags &= ~NFS_MOUNT_SOFT;
 			break;
-		case Opt_intr:
-		case Opt_nointr:
-			break;
 		case Opt_posix:
 			mnt->flags |= NFS_MOUNT_POSIX;
 			break;
@@ -819,20 +1006,14 @@ static int nfs_parse_mount_options(char *raw,
 		case Opt_udp:
 			mnt->flags &= ~NFS_MOUNT_TCP;
 			mnt->nfs_server.protocol = XPRT_TRANSPORT_UDP;
-			mnt->timeo = 7;
-			mnt->retrans = 5;
 			break;
 		case Opt_tcp:
 			mnt->flags |= NFS_MOUNT_TCP;
 			mnt->nfs_server.protocol = XPRT_TRANSPORT_TCP;
-			mnt->timeo = 600;
-			mnt->retrans = 2;
 			break;
 		case Opt_rdma:
 			mnt->flags |= NFS_MOUNT_TCP; /* for side protocols */
 			mnt->nfs_server.protocol = XPRT_TRANSPORT_RDMA;
-			mnt->timeo = 600;
-			mnt->retrans = 2;
 			break;
 		case Opt_acl:
 			mnt->flags &= ~NFS_MOUNT_NOACL;
@@ -853,165 +1034,144 @@ static int nfs_parse_mount_options(char *raw,
 			mnt->flags |= NFS_MOUNT_UNSHARED;
 			break;
 
+		/*
+		 * options that take numeric values
+		 */
 		case Opt_port:
-			if (match_int(args, &option))
-				return 0;
-			if (option < 0 || option > 65535)
-				return 0;
-			mnt->nfs_server.port = option;
+			if (match_int(args, &option) ||
+			    option < 0 || option > USHORT_MAX) {
+				errors++;
+				nfs_parse_invalid_value("port");
+			} else
+				mnt->nfs_server.port = option;
 			break;
 		case Opt_rsize:
-			if (match_int(args, &mnt->rsize))
-				return 0;
+			if (match_int(args, &option) || option < 0) {
+				errors++;
+				nfs_parse_invalid_value("rsize");
+			} else
+				mnt->rsize = option;
 			break;
 		case Opt_wsize:
-			if (match_int(args, &mnt->wsize))
-				return 0;
+			if (match_int(args, &option) || option < 0) {
+				errors++;
+				nfs_parse_invalid_value("wsize");
+			} else
+				mnt->wsize = option;
 			break;
 		case Opt_bsize:
-			if (match_int(args, &option))
-				return 0;
-			if (option < 0)
-				return 0;
-			mnt->bsize = option;
+			if (match_int(args, &option) || option < 0) {
+				errors++;
+				nfs_parse_invalid_value("bsize");
+			} else
+				mnt->bsize = option;
 			break;
 		case Opt_timeo:
-			if (match_int(args, &mnt->timeo))
-				return 0;
+			if (match_int(args, &option) || option <= 0) {
+				errors++;
+				nfs_parse_invalid_value("timeo");
+			} else
+				mnt->timeo = option;
 			break;
 		case Opt_retrans:
-			if (match_int(args, &mnt->retrans))
-				return 0;
+			if (match_int(args, &option) || option <= 0) {
+				errors++;
+				nfs_parse_invalid_value("retrans");
+			} else
+				mnt->retrans = option;
 			break;
 		case Opt_acregmin:
-			if (match_int(args, &mnt->acregmin))
-				return 0;
+			if (match_int(args, &option) || option < 0) {
+				errors++;
+				nfs_parse_invalid_value("acregmin");
+			} else
+				mnt->acregmin = option;
 			break;
 		case Opt_acregmax:
-			if (match_int(args, &mnt->acregmax))
-				return 0;
+			if (match_int(args, &option) || option < 0) {
+				errors++;
+				nfs_parse_invalid_value("acregmax");
+			} else
+				mnt->acregmax = option;
 			break;
 		case Opt_acdirmin:
-			if (match_int(args, &mnt->acdirmin))
-				return 0;
+			if (match_int(args, &option) || option < 0) {
+				errors++;
+				nfs_parse_invalid_value("acdirmin");
+			} else
+				mnt->acdirmin = option;
 			break;
 		case Opt_acdirmax:
-			if (match_int(args, &mnt->acdirmax))
-				return 0;
+			if (match_int(args, &option) || option < 0) {
+				errors++;
+				nfs_parse_invalid_value("acdirmax");
+			} else
+				mnt->acdirmax = option;
 			break;
 		case Opt_actimeo:
-			if (match_int(args, &option))
-				return 0;
-			if (option < 0)
-				return 0;
-			mnt->acregmin =
-			mnt->acregmax =
-			mnt->acdirmin =
-			mnt->acdirmax = option;
+			if (match_int(args, &option) || option < 0) {
+				errors++;
+				nfs_parse_invalid_value("actimeo");
+			} else
+				mnt->acregmin = mnt->acregmax =
+				mnt->acdirmin = mnt->acdirmax = option;
 			break;
 		case Opt_namelen:
-			if (match_int(args, &mnt->namlen))
-				return 0;
+			if (match_int(args, &option) || option < 0) {
+				errors++;
+				nfs_parse_invalid_value("namlen");
+			} else
+				mnt->namlen = option;
 			break;
 		case Opt_mountport:
-			if (match_int(args, &option))
-				return 0;
-			if (option < 0 || option > 65535)
-				return 0;
-			mnt->mount_server.port = option;
+			if (match_int(args, &option) ||
+			    option < 0 || option > USHORT_MAX) {
+				errors++;
+				nfs_parse_invalid_value("mountport");
+			} else
+				mnt->mount_server.port = option;
 			break;
 		case Opt_mountvers:
-			if (match_int(args, &option))
-				return 0;
-			if (option < 0)
-				return 0;
-			mnt->mount_server.version = option;
+			if (match_int(args, &option) ||
+			    option < NFS_MNT_VERSION ||
+			    option > NFS_MNT3_VERSION) {
+				errors++;
+				nfs_parse_invalid_value("mountvers");
+			} else
+				mnt->mount_server.version = option;
 			break;
 		case Opt_nfsvers:
-			if (match_int(args, &option))
-				return 0;
+			if (match_int(args, &option)) {
+				errors++;
+				nfs_parse_invalid_value("nfsvers");
+				break;
+			}
 			switch (option) {
-			case 2:
+			case NFS2_VERSION:
 				mnt->flags &= ~NFS_MOUNT_VER3;
 				break;
-			case 3:
+			case NFS3_VERSION:
 				mnt->flags |= NFS_MOUNT_VER3;
 				break;
 			default:
-				goto out_unrec_vers;
+				errors++;
+				nfs_parse_invalid_value("nfsvers");
 			}
 			break;
 
+		/*
+		 * options that take text values
+		 */
 		case Opt_sec:
 			string = match_strdup(args);
 			if (string == NULL)
 				goto out_nomem;
-			token = match_token(string, nfs_secflavor_tokens, args);
+			rc = nfs_parse_security_flavors(string, mnt);
 			kfree(string);
-
-			/*
-			 * The flags setting is for v2/v3.  The flavor_len
-			 * setting is for v4.  v2/v3 also need to know the
-			 * difference between NULL and UNIX.
-			 */
-			switch (token) {
-			case Opt_sec_none:
-				mnt->flags &= ~NFS_MOUNT_SECFLAVOUR;
-				mnt->auth_flavor_len = 0;
-				mnt->auth_flavors[0] = RPC_AUTH_NULL;
-				break;
-			case Opt_sec_sys:
-				mnt->flags &= ~NFS_MOUNT_SECFLAVOUR;
-				mnt->auth_flavor_len = 0;
-				mnt->auth_flavors[0] = RPC_AUTH_UNIX;
-				break;
-			case Opt_sec_krb5:
-				mnt->flags |= NFS_MOUNT_SECFLAVOUR;
-				mnt->auth_flavor_len = 1;
-				mnt->auth_flavors[0] = RPC_AUTH_GSS_KRB5;
-				break;
-			case Opt_sec_krb5i:
-				mnt->flags |= NFS_MOUNT_SECFLAVOUR;
-				mnt->auth_flavor_len = 1;
-				mnt->auth_flavors[0] = RPC_AUTH_GSS_KRB5I;
-				break;
-			case Opt_sec_krb5p:
-				mnt->flags |= NFS_MOUNT_SECFLAVOUR;
-				mnt->auth_flavor_len = 1;
-				mnt->auth_flavors[0] = RPC_AUTH_GSS_KRB5P;
-				break;
-			case Opt_sec_lkey:
-				mnt->flags |= NFS_MOUNT_SECFLAVOUR;
-				mnt->auth_flavor_len = 1;
-				mnt->auth_flavors[0] = RPC_AUTH_GSS_LKEY;
-				break;
-			case Opt_sec_lkeyi:
-				mnt->flags |= NFS_MOUNT_SECFLAVOUR;
-				mnt->auth_flavor_len = 1;
-				mnt->auth_flavors[0] = RPC_AUTH_GSS_LKEYI;
-				break;
-			case Opt_sec_lkeyp:
-				mnt->flags |= NFS_MOUNT_SECFLAVOUR;
-				mnt->auth_flavor_len = 1;
-				mnt->auth_flavors[0] = RPC_AUTH_GSS_LKEYP;
-				break;
-			case Opt_sec_spkm:
-				mnt->flags |= NFS_MOUNT_SECFLAVOUR;
-				mnt->auth_flavor_len = 1;
-				mnt->auth_flavors[0] = RPC_AUTH_GSS_SPKM;
-				break;
-			case Opt_sec_spkmi:
-				mnt->flags |= NFS_MOUNT_SECFLAVOUR;
-				mnt->auth_flavor_len = 1;
-				mnt->auth_flavors[0] = RPC_AUTH_GSS_SPKMI;
-				break;
-			case Opt_sec_spkmp:
-				mnt->flags |= NFS_MOUNT_SECFLAVOUR;
-				mnt->auth_flavor_len = 1;
-				mnt->auth_flavors[0] = RPC_AUTH_GSS_SPKMP;
-				break;
-			default:
-				goto out_unrec_sec;
+			if (!rc) {
+				errors++;
+				dfprintk(MOUNT, "NFS:   unrecognized "
+						"security flavor\n");
 			}
 			break;
 		case Opt_proto:
@@ -1026,24 +1186,20 @@ static int nfs_parse_mount_options(char *raw,
 			case Opt_xprt_udp:
 				mnt->flags &= ~NFS_MOUNT_TCP;
 				mnt->nfs_server.protocol = XPRT_TRANSPORT_UDP;
-				mnt->timeo = 7;
-				mnt->retrans = 5;
 				break;
 			case Opt_xprt_tcp:
 				mnt->flags |= NFS_MOUNT_TCP;
 				mnt->nfs_server.protocol = XPRT_TRANSPORT_TCP;
-				mnt->timeo = 600;
-				mnt->retrans = 2;
 				break;
 			case Opt_xprt_rdma:
 				/* vector side protocols to TCP */
 				mnt->flags |= NFS_MOUNT_TCP;
 				mnt->nfs_server.protocol = XPRT_TRANSPORT_RDMA;
-				mnt->timeo = 600;
-				mnt->retrans = 2;
 				break;
 			default:
-				goto out_unrec_xprt;
+				errors++;
+				dfprintk(MOUNT, "NFS:   unrecognized "
+						"transport protocol\n");
 			}
 			break;
 		case Opt_mountproto:
@@ -1063,16 +1219,19 @@ static int nfs_parse_mount_options(char *raw,
 				break;
 			case Opt_xprt_rdma: /* not used for side protocols */
 			default:
-				goto out_unrec_xprt;
+				errors++;
+				dfprintk(MOUNT, "NFS:   unrecognized "
+						"transport protocol\n");
 			}
 			break;
 		case Opt_addr:
 			string = match_strdup(args);
 			if (string == NULL)
 				goto out_nomem;
-			nfs_parse_server_address(string, (struct sockaddr *)
-						 &mnt->nfs_server.address,
-						 &mnt->nfs_server.addrlen);
+			nfs_parse_ip_address(string, strlen(string),
+					     (struct sockaddr *)
+						&mnt->nfs_server.address,
+					     &mnt->nfs_server.addrlen);
 			kfree(string);
 			break;
 		case Opt_clientaddr:
@@ -1093,24 +1252,33 @@ static int nfs_parse_mount_options(char *raw,
 			string = match_strdup(args);
 			if (string == NULL)
 				goto out_nomem;
-			nfs_parse_server_address(string, (struct sockaddr *)
-						 &mnt->mount_server.address,
-						 &mnt->mount_server.addrlen);
+			nfs_parse_ip_address(string, strlen(string),
+					     (struct sockaddr *)
+						&mnt->mount_server.address,
+					     &mnt->mount_server.addrlen);
 			kfree(string);
 			break;
 
+		/*
+		 * Special options
+		 */
+		case Opt_sloppy:
+			sloppy = 1;
+			dfprintk(MOUNT, "NFS:   relaxing parsing rules\n");
+			break;
 		case Opt_userspace:
 		case Opt_deprecated:
+			dfprintk(MOUNT, "NFS:   ignoring mount option "
+					"'%s'\n", p);
 			break;
 
 		default:
-			goto out_unknown;
+			errors++;
+			dfprintk(MOUNT, "NFS:   unrecognized mount option "
+					"'%s'\n", p);
 		}
 	}
 
-	nfs_set_port((struct sockaddr *)&mnt->nfs_server.address,
-				mnt->nfs_server.port);
-
 	return 1;
 
 out_nomem:
@@ -1120,21 +1288,6 @@ out_security_failure:
 	free_secdata(secdata);
 	printk(KERN_INFO "NFS: security options invalid: %d\n", rc);
 	return 0;
-out_unrec_vers:
-	printk(KERN_INFO "NFS: unrecognized NFS version number\n");
-	return 0;
-
-out_unrec_xprt:
-	printk(KERN_INFO "NFS: unrecognized transport protocol\n");
-	return 0;
-
-out_unrec_sec:
-	printk(KERN_INFO "NFS: unrecognized security flavor\n");
-	return 0;
-
-out_unknown:
-	printk(KERN_INFO "NFS: unknown mount option: %s\n", p);
-	return 0;
 }
 
 /*
@@ -1188,11 +1341,146 @@ static int nfs_try_mount(struct nfs_parsed_mount_data *args,
 	if (status == 0)
 		return 0;
 
-	dfprintk(MOUNT, "NFS: unable to mount server %s, error %d",
+	dfprintk(MOUNT, "NFS: unable to mount server %s, error %d\n",
 			hostname, status);
 	return status;
 }
 
+static int nfs_parse_simple_hostname(const char *dev_name,
+				     char **hostname, size_t maxnamlen,
+				     char **export_path, size_t maxpathlen)
+{
+	size_t len;
+	char *colon, *comma;
+
+	colon = strchr(dev_name, ':');
+	if (colon == NULL)
+		goto out_bad_devname;
+
+	len = colon - dev_name;
+	if (len > maxnamlen)
+		goto out_hostname;
+
+	/* N.B. caller will free nfs_server.hostname in all cases */
+	*hostname = kstrndup(dev_name, len, GFP_KERNEL);
+	if (!*hostname)
+		goto out_nomem;
+
+	/* kill possible hostname list: not supported */
+	comma = strchr(*hostname, ',');
+	if (comma != NULL) {
+		if (comma == *hostname)
+			goto out_bad_devname;
+		*comma = '\0';
+	}
+
+	colon++;
+	len = strlen(colon);
+	if (len > maxpathlen)
+		goto out_path;
+	*export_path = kstrndup(colon, len, GFP_KERNEL);
+	if (!*export_path)
+		goto out_nomem;
+
+	dfprintk(MOUNT, "NFS: MNTPATH: '%s'\n", *export_path);
+	return 0;
+
+out_bad_devname:
+	dfprintk(MOUNT, "NFS: device name not in host:path format\n");
+	return -EINVAL;
+
+out_nomem:
+	dfprintk(MOUNT, "NFS: not enough memory to parse device name\n");
+	return -ENOMEM;
+
+out_hostname:
+	dfprintk(MOUNT, "NFS: server hostname too long\n");
+	return -ENAMETOOLONG;
+
+out_path:
+	dfprintk(MOUNT, "NFS: export pathname too long\n");
+	return -ENAMETOOLONG;
+}
+
+/*
+ * Hostname has square brackets around it because it contains one or
+ * more colons.  We look for the first closing square bracket, and a
+ * colon must follow it.
+ */
+static int nfs_parse_protected_hostname(const char *dev_name,
+					char **hostname, size_t maxnamlen,
+					char **export_path, size_t maxpathlen)
+{
+	size_t len;
+	char *start, *end;
+
+	start = (char *)(dev_name + 1);
+
+	end = strchr(start, ']');
+	if (end == NULL)
+		goto out_bad_devname;
+	if (*(end + 1) != ':')
+		goto out_bad_devname;
+
+	len = end - start;
+	if (len > maxnamlen)
+		goto out_hostname;
+
+	/* N.B. caller will free nfs_server.hostname in all cases */
+	*hostname = kstrndup(start, len, GFP_KERNEL);
+	if (*hostname == NULL)
+		goto out_nomem;
+
+	end += 2;
+	len = strlen(end);
+	if (len > maxpathlen)
+		goto out_path;
+	*export_path = kstrndup(end, len, GFP_KERNEL);
+	if (!*export_path)
+		goto out_nomem;
+
+	return 0;
+
+out_bad_devname:
+	dfprintk(MOUNT, "NFS: device name not in host:path format\n");
+	return -EINVAL;
+
+out_nomem:
+	dfprintk(MOUNT, "NFS: not enough memory to parse device name\n");
+	return -ENOMEM;
+
+out_hostname:
+	dfprintk(MOUNT, "NFS: server hostname too long\n");
+	return -ENAMETOOLONG;
+
+out_path:
+	dfprintk(MOUNT, "NFS: export pathname too long\n");
+	return -ENAMETOOLONG;
+}
+
+/*
+ * Split "dev_name" into "hostname:export_path".
+ *
+ * The leftmost colon demarks the split between the server's hostname
+ * and the export path.  If the hostname starts with a left square
+ * bracket, then it may contain colons.
+ *
+ * Note: caller frees hostname and export path, even on error.
+ */
+static int nfs_parse_devname(const char *dev_name,
+			     char **hostname, size_t maxnamlen,
+			     char **export_path, size_t maxpathlen)
+{
+	if (*dev_name == '[')
+		return nfs_parse_protected_hostname(dev_name,
+						    hostname, maxnamlen,
+						    export_path, maxpathlen);
+
+	return nfs_parse_simple_hostname(dev_name,
+					 hostname, maxnamlen,
+					 export_path, maxpathlen);
+}
+
 /*
  * Validate the NFS2/NFS3 mount data
  * - fills in the mount root filehandle
@@ -1222,16 +1510,14 @@ static int nfs_validate_mount_data(void *options,
 	args->flags		= (NFS_MOUNT_VER3 | NFS_MOUNT_TCP);
 	args->rsize		= NFS_MAX_FILE_IO_SIZE;
 	args->wsize		= NFS_MAX_FILE_IO_SIZE;
-	args->timeo		= 600;
-	args->retrans		= 2;
-	args->acregmin		= 3;
-	args->acregmax		= 60;
-	args->acdirmin		= 30;
-	args->acdirmax		= 60;
+	args->acregmin		= NFS_DEF_ACREGMIN;
+	args->acregmax		= NFS_DEF_ACREGMAX;
+	args->acdirmin		= NFS_DEF_ACDIRMIN;
+	args->acdirmax		= NFS_DEF_ACDIRMAX;
 	args->mount_server.port	= 0;	/* autobind unless user sets port */
-	args->mount_server.protocol = XPRT_TRANSPORT_UDP;
 	args->nfs_server.port	= 0;	/* autobind unless user sets port */
 	args->nfs_server.protocol = XPRT_TRANSPORT_TCP;
+	args->auth_flavors[0]	= RPC_AUTH_UNIX;
 
 	switch (data->version) {
 	case 1:
@@ -1289,7 +1575,9 @@ static int nfs_validate_mount_data(void *options,
 		args->nfs_server.hostname = kstrdup(data->hostname, GFP_KERNEL);
 		args->namlen		= data->namlen;
 		args->bsize		= data->bsize;
-		args->auth_flavors[0]	= data->pseudoflavor;
+
+		if (data->flags & NFS_MOUNT_SECFLAVOUR)
+			args->auth_flavors[0] = data->pseudoflavor;
 		if (!args->nfs_server.hostname)
 			goto out_nomem;
 
@@ -1321,8 +1609,6 @@ static int nfs_validate_mount_data(void *options,
 
 		break;
 	default: {
-		unsigned int len;
-		char *c;
 		int status;
 
 		if (nfs_parse_mount_options((char *)options, args) == 0)
@@ -1332,21 +1618,22 @@ static int nfs_validate_mount_data(void *options,
 						&args->nfs_server.address))
 			goto out_no_address;
 
-		c = strchr(dev_name, ':');
-		if (c == NULL)
-			return -EINVAL;
-		len = c - dev_name;
-		/* N.B. caller will free nfs_server.hostname in all cases */
-		args->nfs_server.hostname = kstrndup(dev_name, len, GFP_KERNEL);
-		if (!args->nfs_server.hostname)
-			goto out_nomem;
+		nfs_set_port((struct sockaddr *)&args->nfs_server.address,
+				args->nfs_server.port);
 
-		c++;
-		if (strlen(c) > NFS_MAXPATHLEN)
-			return -ENAMETOOLONG;
-		args->nfs_server.export_path = c;
+		nfs_set_mount_transport_protocol(args);
+
+		status = nfs_parse_devname(dev_name,
+					   &args->nfs_server.hostname,
+					   PAGE_SIZE,
+					   &args->nfs_server.export_path,
+					   NFS_MAXPATHLEN);
+		if (!status)
+			status = nfs_try_mount(args, mntfh);
+
+		kfree(args->nfs_server.export_path);
+		args->nfs_server.export_path = NULL;
 
-		status = nfs_try_mount(args, mntfh);
 		if (status)
 			return status;
 
@@ -1354,9 +1641,6 @@ static int nfs_validate_mount_data(void *options,
 		}
 	}
 
-	if (!(args->flags & NFS_MOUNT_SECFLAVOUR))
-		args->auth_flavors[0] = RPC_AUTH_UNIX;
-
 #ifndef CONFIG_NFS_V3
 	if (args->flags & NFS_MOUNT_VER3)
 		goto out_v3_not_compiled;
@@ -1396,6 +1680,80 @@ out_invalid_fh:
 	return -EINVAL;
 }
 
+static int
+nfs_compare_remount_data(struct nfs_server *nfss,
+			 struct nfs_parsed_mount_data *data)
+{
+	if (data->flags != nfss->flags ||
+	    data->rsize != nfss->rsize ||
+	    data->wsize != nfss->wsize ||
+	    data->retrans != nfss->client->cl_timeout->to_retries ||
+	    data->auth_flavors[0] != nfss->client->cl_auth->au_flavor ||
+	    data->acregmin != nfss->acregmin / HZ ||
+	    data->acregmax != nfss->acregmax / HZ ||
+	    data->acdirmin != nfss->acdirmin / HZ ||
+	    data->acdirmax != nfss->acdirmax / HZ ||
+	    data->timeo != (10U * nfss->client->cl_timeout->to_initval / HZ) ||
+	    data->nfs_server.addrlen != nfss->nfs_client->cl_addrlen ||
+	    memcmp(&data->nfs_server.address, &nfss->nfs_client->cl_addr,
+		   data->nfs_server.addrlen) != 0)
+		return -EINVAL;
+
+	return 0;
+}
+
+static int
+nfs_remount(struct super_block *sb, int *flags, char *raw_data)
+{
+	int error;
+	struct nfs_server *nfss = sb->s_fs_info;
+	struct nfs_parsed_mount_data *data;
+	struct nfs_mount_data *options = (struct nfs_mount_data *)raw_data;
+	struct nfs4_mount_data *options4 = (struct nfs4_mount_data *)raw_data;
+	u32 nfsvers = nfss->nfs_client->rpc_ops->version;
+
+	/*
+	 * Userspace mount programs that send binary options generally send
+	 * them populated with default values. We have no way to know which
+	 * ones were explicitly specified. Fall back to legacy behavior and
+	 * just return success.
+	 */
+	if ((nfsvers == 4 && options4->version == 1) ||
+	    (nfsvers <= 3 && options->version >= 1 &&
+	     options->version <= 6))
+		return 0;
+
+	data = kzalloc(sizeof(*data), GFP_KERNEL);
+	if (data == NULL)
+		return -ENOMEM;
+
+	/* fill out struct with values from existing mount */
+	data->flags = nfss->flags;
+	data->rsize = nfss->rsize;
+	data->wsize = nfss->wsize;
+	data->retrans = nfss->client->cl_timeout->to_retries;
+	data->auth_flavors[0] = nfss->client->cl_auth->au_flavor;
+	data->acregmin = nfss->acregmin / HZ;
+	data->acregmax = nfss->acregmax / HZ;
+	data->acdirmin = nfss->acdirmin / HZ;
+	data->acdirmax = nfss->acdirmax / HZ;
+	data->timeo = 10U * nfss->client->cl_timeout->to_initval / HZ;
+	data->nfs_server.addrlen = nfss->nfs_client->cl_addrlen;
+	memcpy(&data->nfs_server.address, &nfss->nfs_client->cl_addr,
+		data->nfs_server.addrlen);
+
+	/* overwrite those values with any that were specified */
+	error = nfs_parse_mount_options((char *)options, data);
+	if (error < 0)
+		goto out;
+
+	/* compare new mount options with old ones */
+	error = nfs_compare_remount_data(nfss, data);
+out:
+	kfree(data);
+	return error;
+}
+
 /*
  * Initialise the common bits of the superblock
  */
@@ -1811,14 +2169,13 @@ static int nfs4_validate_mount_data(void *options,
 
 	args->rsize		= NFS_MAX_FILE_IO_SIZE;
 	args->wsize		= NFS_MAX_FILE_IO_SIZE;
-	args->timeo		= 600;
-	args->retrans		= 2;
-	args->acregmin		= 3;
-	args->acregmax		= 60;
-	args->acdirmin		= 30;
-	args->acdirmax		= 60;
+	args->acregmin		= NFS_DEF_ACREGMIN;
+	args->acregmax		= NFS_DEF_ACREGMAX;
+	args->acdirmin		= NFS_DEF_ACDIRMIN;
+	args->acdirmax		= NFS_DEF_ACDIRMAX;
 	args->nfs_server.port	= NFS_PORT; /* 2049 unless user set port= */
-	args->nfs_server.protocol = XPRT_TRANSPORT_TCP;
+	args->auth_flavors[0]	= RPC_AUTH_UNIX;
+	args->auth_flavor_len	= 0;
 
 	switch (data->version) {
 	case 1:
@@ -1834,18 +2191,13 @@ static int nfs4_validate_mount_data(void *options,
 						&args->nfs_server.address))
 			goto out_no_address;
 
-		switch (data->auth_flavourlen) {
-		case 0:
-			args->auth_flavors[0] = RPC_AUTH_UNIX;
-			break;
-		case 1:
+		if (data->auth_flavourlen) {
+			if (data->auth_flavourlen > 1)
+				goto out_inval_auth;
 			if (copy_from_user(&args->auth_flavors[0],
 					   data->auth_flavours,
 					   sizeof(args->auth_flavors[0])))
 				return -EFAULT;
-			break;
-		default:
-			goto out_inval_auth;
 		}
 
 		c = strndup_user(data->hostname.data, NFS4_MAXNAMLEN);
@@ -1879,10 +2231,11 @@ static int nfs4_validate_mount_data(void *options,
 		args->acdirmin	= data->acdirmin;
 		args->acdirmax	= data->acdirmax;
 		args->nfs_server.protocol = data->proto;
+		nfs_validate_transport_protocol(args);
 
 		break;
 	default: {
-		unsigned int len;
+		int status;
 
 		if (nfs_parse_mount_options((char *)options, args) == 0)
 			return -EINVAL;
@@ -1891,44 +2244,25 @@ static int nfs4_validate_mount_data(void *options,
 						&args->nfs_server.address))
 			return -EINVAL;
 
-		switch (args->auth_flavor_len) {
-		case 0:
-			args->auth_flavors[0] = RPC_AUTH_UNIX;
-			break;
-		case 1:
-			break;
-		default:
-			goto out_inval_auth;
-		}
+		nfs_set_port((struct sockaddr *)&args->nfs_server.address,
+				args->nfs_server.port);
 
-		/*
-		 * Split "dev_name" into "hostname:mntpath".
-		 */
-		c = strchr(dev_name, ':');
-		if (c == NULL)
-			return -EINVAL;
-		/* while calculating len, pretend ':' is '\0' */
-		len = c - dev_name;
-		if (len > NFS4_MAXNAMLEN)
-			return -ENAMETOOLONG;
-		/* N.B. caller will free nfs_server.hostname in all cases */
-		args->nfs_server.hostname = kstrndup(dev_name, len, GFP_KERNEL);
-		if (!args->nfs_server.hostname)
-			goto out_nomem;
-
-		c++;			/* step over the ':' */
-		len = strlen(c);
-		if (len > NFS4_MAXPATHLEN)
-			return -ENAMETOOLONG;
-		args->nfs_server.export_path = kstrndup(c, len, GFP_KERNEL);
-		if (!args->nfs_server.export_path)
-			goto out_nomem;
+		nfs_validate_transport_protocol(args);
 
-		dprintk("NFS: MNTPATH: '%s'\n", args->nfs_server.export_path);
+		if (args->auth_flavor_len > 1)
+			goto out_inval_auth;
 
 		if (args->client_address == NULL)
 			goto out_no_client_address;
 
+		status = nfs_parse_devname(dev_name,
+					   &args->nfs_server.hostname,
+					   NFS4_MAXNAMLEN,
+					   &args->nfs_server.export_path,
+					   NFS4_MAXPATHLEN);
+		if (status < 0)
+			return status;
+
 		break;
 		}
 	}
@@ -1944,10 +2278,6 @@ out_inval_auth:
 		 data->auth_flavourlen);
 	return -EINVAL;
 
-out_nomem:
-	dfprintk(MOUNT, "NFS4: not enough memory to handle mount options\n");
-	return -ENOMEM;
-
 out_no_address:
 	dfprintk(MOUNT, "NFS4: mount program didn't pass remote address\n");
 	return -EINVAL;
diff --git a/fs/nfs/write.c b/fs/nfs/write.c
index f333848fd3b..3229e217c77 100644
--- a/fs/nfs/write.c
+++ b/fs/nfs/write.c
@@ -34,9 +34,6 @@
 /*
  * Local function declarations
  */
-static struct nfs_page * nfs_update_request(struct nfs_open_context*,
-					    struct page *,
-					    unsigned int, unsigned int);
 static void nfs_pageio_init_write(struct nfs_pageio_descriptor *desc,
 				  struct inode *inode, int ioflags);
 static void nfs_redirty_request(struct nfs_page *req);
@@ -136,16 +133,21 @@ static struct nfs_page *nfs_page_find_request(struct page *page)
 static void nfs_grow_file(struct page *page, unsigned int offset, unsigned int count)
 {
 	struct inode *inode = page->mapping->host;
-	loff_t end, i_size = i_size_read(inode);
-	pgoff_t end_index = (i_size - 1) >> PAGE_CACHE_SHIFT;
+	loff_t end, i_size;
+	pgoff_t end_index;
 
+	spin_lock(&inode->i_lock);
+	i_size = i_size_read(inode);
+	end_index = (i_size - 1) >> PAGE_CACHE_SHIFT;
 	if (i_size > 0 && page->index < end_index)
-		return;
+		goto out;
 	end = ((loff_t)page->index << PAGE_CACHE_SHIFT) + ((loff_t)offset+count);
 	if (i_size >= end)
-		return;
-	nfs_inc_stats(inode, NFSIOS_EXTENDWRITE);
+		goto out;
 	i_size_write(inode, end);
+	nfs_inc_stats(inode, NFSIOS_EXTENDWRITE);
+out:
+	spin_unlock(&inode->i_lock);
 }
 
 /* A writeback failed: mark the page as bad, and invalidate the page cache */
@@ -169,29 +171,6 @@ static void nfs_mark_uptodate(struct page *page, unsigned int base, unsigned int
 	SetPageUptodate(page);
 }
 
-static int nfs_writepage_setup(struct nfs_open_context *ctx, struct page *page,
-		unsigned int offset, unsigned int count)
-{
-	struct nfs_page	*req;
-	int ret;
-
-	for (;;) {
-		req = nfs_update_request(ctx, page, offset, count);
-		if (!IS_ERR(req))
-			break;
-		ret = PTR_ERR(req);
-		if (ret != -EBUSY)
-			return ret;
-		ret = nfs_wb_page(page->mapping->host, page);
-		if (ret != 0)
-			return ret;
-	}
-	/* Update file length */
-	nfs_grow_file(page, offset, count);
-	nfs_clear_page_tag_locked(req);
-	return 0;
-}
-
 static int wb_priority(struct writeback_control *wbc)
 {
 	if (wbc->for_reclaim)
@@ -268,12 +247,9 @@ static int nfs_page_async_flush(struct nfs_pageio_descriptor *pgio,
 			return ret;
 		spin_lock(&inode->i_lock);
 	}
-	if (test_bit(PG_NEED_COMMIT, &req->wb_flags)) {
-		/* This request is marked for commit */
+	if (test_bit(PG_CLEAN, &req->wb_flags)) {
 		spin_unlock(&inode->i_lock);
-		nfs_clear_page_tag_locked(req);
-		nfs_pageio_complete(pgio);
-		return 0;
+		BUG();
 	}
 	if (nfs_set_page_writeback(page) != 0) {
 		spin_unlock(&inode->i_lock);
@@ -355,11 +331,19 @@ int nfs_writepages(struct address_space *mapping, struct writeback_control *wbc)
 /*
  * Insert a write request into an inode
  */
-static void nfs_inode_add_request(struct inode *inode, struct nfs_page *req)
+static int nfs_inode_add_request(struct inode *inode, struct nfs_page *req)
 {
 	struct nfs_inode *nfsi = NFS_I(inode);
 	int error;
 
+	error = radix_tree_preload(GFP_NOFS);
+	if (error != 0)
+		goto out;
+
+	/* Lock the request! */
+	nfs_lock_request_dontget(req);
+
+	spin_lock(&inode->i_lock);
 	error = radix_tree_insert(&nfsi->nfs_page_tree, req->wb_index, req);
 	BUG_ON(error);
 	if (!nfsi->npages) {
@@ -373,6 +357,10 @@ static void nfs_inode_add_request(struct inode *inode, struct nfs_page *req)
 	kref_get(&req->wb_kref);
 	radix_tree_tag_set(&nfsi->nfs_page_tree, req->wb_index,
 				NFS_PAGE_TAG_LOCKED);
+	spin_unlock(&inode->i_lock);
+	radix_tree_preload_end();
+out:
+	return error;
 }
 
 /*
@@ -405,19 +393,6 @@ nfs_mark_request_dirty(struct nfs_page *req)
 	__set_page_dirty_nobuffers(req->wb_page);
 }
 
-/*
- * Check if a request is dirty
- */
-static inline int
-nfs_dirty_request(struct nfs_page *req)
-{
-	struct page *page = req->wb_page;
-
-	if (page == NULL || test_bit(PG_NEED_COMMIT, &req->wb_flags))
-		return 0;
-	return !PageWriteback(page);
-}
-
 #if defined(CONFIG_NFS_V3) || defined(CONFIG_NFS_V4)
 /*
  * Add a request to the inode's commit list.
@@ -430,7 +405,7 @@ nfs_mark_request_commit(struct nfs_page *req)
 
 	spin_lock(&inode->i_lock);
 	nfsi->ncommit++;
-	set_bit(PG_NEED_COMMIT, &(req)->wb_flags);
+	set_bit(PG_CLEAN, &(req)->wb_flags);
 	radix_tree_tag_set(&nfsi->nfs_page_tree,
 			req->wb_index,
 			NFS_PAGE_TAG_COMMIT);
@@ -440,6 +415,19 @@ nfs_mark_request_commit(struct nfs_page *req)
 	__mark_inode_dirty(inode, I_DIRTY_DATASYNC);
 }
 
+static int
+nfs_clear_request_commit(struct nfs_page *req)
+{
+	struct page *page = req->wb_page;
+
+	if (test_and_clear_bit(PG_CLEAN, &(req)->wb_flags)) {
+		dec_zone_page_state(page, NR_UNSTABLE_NFS);
+		dec_bdi_stat(page->mapping->backing_dev_info, BDI_RECLAIMABLE);
+		return 1;
+	}
+	return 0;
+}
+
 static inline
 int nfs_write_need_commit(struct nfs_write_data *data)
 {
@@ -449,7 +437,7 @@ int nfs_write_need_commit(struct nfs_write_data *data)
 static inline
 int nfs_reschedule_unstable_write(struct nfs_page *req)
 {
-	if (test_bit(PG_NEED_COMMIT, &req->wb_flags)) {
+	if (test_and_clear_bit(PG_NEED_COMMIT, &req->wb_flags)) {
 		nfs_mark_request_commit(req);
 		return 1;
 	}
@@ -465,6 +453,12 @@ nfs_mark_request_commit(struct nfs_page *req)
 {
 }
 
+static inline int
+nfs_clear_request_commit(struct nfs_page *req)
+{
+	return 0;
+}
+
 static inline
 int nfs_write_need_commit(struct nfs_write_data *data)
 {
@@ -522,11 +516,8 @@ static void nfs_cancel_commit_list(struct list_head *head)
 
 	while(!list_empty(head)) {
 		req = nfs_list_entry(head->next);
-		dec_zone_page_state(req->wb_page, NR_UNSTABLE_NFS);
-		dec_bdi_stat(req->wb_page->mapping->backing_dev_info,
-				BDI_RECLAIMABLE);
 		nfs_list_remove_request(req);
-		clear_bit(PG_NEED_COMMIT, &(req)->wb_flags);
+		nfs_clear_request_commit(req);
 		nfs_inode_remove_request(req);
 		nfs_unlock_request(req);
 	}
@@ -564,110 +555,124 @@ static inline int nfs_scan_commit(struct inode *inode, struct list_head *dst, pg
 #endif
 
 /*
- * Try to update any existing write request, or create one if there is none.
- * In order to match, the request's credentials must match those of
- * the calling process.
+ * Search for an existing write request, and attempt to update
+ * it to reflect a new dirty region on a given page.
  *
- * Note: Should always be called with the Page Lock held!
+ * If the attempt fails, then the existing request is flushed out
+ * to disk.
  */
-static struct nfs_page * nfs_update_request(struct nfs_open_context* ctx,
-		struct page *page, unsigned int offset, unsigned int bytes)
+static struct nfs_page *nfs_try_to_update_request(struct inode *inode,
+		struct page *page,
+		unsigned int offset,
+		unsigned int bytes)
 {
-	struct address_space *mapping = page->mapping;
-	struct inode *inode = mapping->host;
-	struct nfs_page		*req, *new = NULL;
-	pgoff_t		rqend, end;
+	struct nfs_page *req;
+	unsigned int rqend;
+	unsigned int end;
+	int error;
+
+	if (!PagePrivate(page))
+		return NULL;
 
 	end = offset + bytes;
+	spin_lock(&inode->i_lock);
 
 	for (;;) {
-		/* Loop over all inode entries and see if we find
-		 * A request for the page we wish to update
+		req = nfs_page_find_request_locked(page);
+		if (req == NULL)
+			goto out_unlock;
+
+		rqend = req->wb_offset + req->wb_bytes;
+		/*
+		 * Tell the caller to flush out the request if
+		 * the offsets are non-contiguous.
+		 * Note: nfs_flush_incompatible() will already
+		 * have flushed out requests having wrong owners.
 		 */
-		if (new) {
-			if (radix_tree_preload(GFP_NOFS)) {
-				nfs_release_request(new);
-				return ERR_PTR(-ENOMEM);
-			}
-		}
+		if (offset > rqend
+		    || end < req->wb_offset)
+			goto out_flushme;
 
-		spin_lock(&inode->i_lock);
-		req = nfs_page_find_request_locked(page);
-		if (req) {
-			if (!nfs_set_page_tag_locked(req)) {
-				int error;
-
-				spin_unlock(&inode->i_lock);
-				error = nfs_wait_on_request(req);
-				nfs_release_request(req);
-				if (error < 0) {
-					if (new) {
-						radix_tree_preload_end();
-						nfs_release_request(new);
-					}
-					return ERR_PTR(error);
-				}
-				continue;
-			}
-			spin_unlock(&inode->i_lock);
-			if (new) {
-				radix_tree_preload_end();
-				nfs_release_request(new);
-			}
+		if (nfs_set_page_tag_locked(req))
 			break;
-		}
 
-		if (new) {
-			nfs_lock_request_dontget(new);
-			nfs_inode_add_request(inode, new);
-			spin_unlock(&inode->i_lock);
-			radix_tree_preload_end();
-			req = new;
-			goto zero_page;
-		}
+		/* The request is locked, so wait and then retry */
 		spin_unlock(&inode->i_lock);
-
-		new = nfs_create_request(ctx, inode, page, offset, bytes);
-		if (IS_ERR(new))
-			return new;
+		error = nfs_wait_on_request(req);
+		nfs_release_request(req);
+		if (error != 0)
+			goto out_err;
+		spin_lock(&inode->i_lock);
 	}
 
-	/* We have a request for our page.
-	 * If the creds don't match, or the
-	 * page addresses don't match,
-	 * tell the caller to wait on the conflicting
-	 * request.
-	 */
-	rqend = req->wb_offset + req->wb_bytes;
-	if (req->wb_context != ctx
-	    || req->wb_page != page
-	    || !nfs_dirty_request(req)
-	    || offset > rqend || end < req->wb_offset) {
-		nfs_clear_page_tag_locked(req);
-		return ERR_PTR(-EBUSY);
-	}
+	if (nfs_clear_request_commit(req))
+		radix_tree_tag_clear(&NFS_I(inode)->nfs_page_tree,
+				req->wb_index, NFS_PAGE_TAG_COMMIT);
 
 	/* Okay, the request matches. Update the region */
 	if (offset < req->wb_offset) {
 		req->wb_offset = offset;
 		req->wb_pgbase = offset;
-		req->wb_bytes = max(end, rqend) - req->wb_offset;
-		goto zero_page;
 	}
-
 	if (end > rqend)
 		req->wb_bytes = end - req->wb_offset;
-
+	else
+		req->wb_bytes = rqend - req->wb_offset;
+out_unlock:
+	spin_unlock(&inode->i_lock);
 	return req;
-zero_page:
-	/* If this page might potentially be marked as up to date,
-	 * then we need to zero any uninitalised data. */
-	if (req->wb_pgbase == 0 && req->wb_bytes != PAGE_CACHE_SIZE
-			&& !PageUptodate(req->wb_page))
-		zero_user_segment(req->wb_page, req->wb_bytes, PAGE_CACHE_SIZE);
+out_flushme:
+	spin_unlock(&inode->i_lock);
+	nfs_release_request(req);
+	error = nfs_wb_page(inode, page);
+out_err:
+	return ERR_PTR(error);
+}
+
+/*
+ * Try to update an existing write request, or create one if there is none.
+ *
+ * Note: Should always be called with the Page Lock held to prevent races
+ * if we have to add a new request. Also assumes that the caller has
+ * already called nfs_flush_incompatible() if necessary.
+ */
+static struct nfs_page * nfs_setup_write_request(struct nfs_open_context* ctx,
+		struct page *page, unsigned int offset, unsigned int bytes)
+{
+	struct inode *inode = page->mapping->host;
+	struct nfs_page	*req;
+	int error;
+
+	req = nfs_try_to_update_request(inode, page, offset, bytes);
+	if (req != NULL)
+		goto out;
+	req = nfs_create_request(ctx, inode, page, offset, bytes);
+	if (IS_ERR(req))
+		goto out;
+	error = nfs_inode_add_request(inode, req);
+	if (error != 0) {
+		nfs_release_request(req);
+		req = ERR_PTR(error);
+	}
+out:
 	return req;
 }
 
+static int nfs_writepage_setup(struct nfs_open_context *ctx, struct page *page,
+		unsigned int offset, unsigned int count)
+{
+	struct nfs_page	*req;
+
+	req = nfs_setup_write_request(ctx, page, offset, count);
+	if (IS_ERR(req))
+		return PTR_ERR(req);
+	/* Update file length */
+	nfs_grow_file(page, offset, count);
+	nfs_mark_uptodate(page, req->wb_pgbase, req->wb_bytes);
+	nfs_clear_page_tag_locked(req);
+	return 0;
+}
+
 int nfs_flush_incompatible(struct file *file, struct page *page)
 {
 	struct nfs_open_context *ctx = nfs_file_open_context(file);
@@ -685,8 +690,7 @@ int nfs_flush_incompatible(struct file *file, struct page *page)
 		req = nfs_page_find_request(page);
 		if (req == NULL)
 			return 0;
-		do_flush = req->wb_page != page || req->wb_context != ctx
-			|| !nfs_dirty_request(req);
+		do_flush = req->wb_page != page || req->wb_context != ctx;
 		nfs_release_request(req);
 		if (!do_flush)
 			return 0;
@@ -721,10 +725,10 @@ int nfs_updatepage(struct file *file, struct page *page,
 
 	nfs_inc_stats(inode, NFSIOS_VFSUPDATEPAGE);
 
-	dprintk("NFS:      nfs_updatepage(%s/%s %d@%Ld)\n",
+	dprintk("NFS:       nfs_updatepage(%s/%s %d@%lld)\n",
 		file->f_path.dentry->d_parent->d_name.name,
 		file->f_path.dentry->d_name.name, count,
-		(long long)(page_offset(page) +offset));
+		(long long)(page_offset(page) + offset));
 
 	/* If we're not using byte range locks, and we know the page
 	 * is up to date, it may be more efficient to extend the write
@@ -744,7 +748,7 @@ int nfs_updatepage(struct file *file, struct page *page,
 	else
 		__set_page_dirty_nobuffers(page);
 
-        dprintk("NFS:      nfs_updatepage returns %d (isize %Ld)\n",
+	dprintk("NFS:       nfs_updatepage returns %d (isize %lld)\n",
 			status, (long long)i_size_read(inode));
 	return status;
 }
@@ -752,12 +756,7 @@ int nfs_updatepage(struct file *file, struct page *page,
 static void nfs_writepage_release(struct nfs_page *req)
 {
 
-	if (PageError(req->wb_page)) {
-		nfs_end_page_writeback(req->wb_page);
-		nfs_inode_remove_request(req);
-	} else if (!nfs_reschedule_unstable_write(req)) {
-		/* Set the PG_uptodate flag */
-		nfs_mark_uptodate(req->wb_page, req->wb_pgbase, req->wb_bytes);
+	if (PageError(req->wb_page) || !nfs_reschedule_unstable_write(req)) {
 		nfs_end_page_writeback(req->wb_page);
 		nfs_inode_remove_request(req);
 	} else
@@ -834,7 +833,7 @@ static int nfs_write_rpcsetup(struct nfs_page *req,
 	NFS_PROTO(inode)->write_setup(data, &msg);
 
 	dprintk("NFS: %5u initiated write call "
-		"(req %s/%Ld, %u bytes @ offset %Lu)\n",
+		"(req %s/%lld, %u bytes @ offset %llu)\n",
 		data->task.tk_pid,
 		inode->i_sb->s_id,
 		(long long)NFS_FILEID(inode),
@@ -978,13 +977,13 @@ static void nfs_pageio_init_write(struct nfs_pageio_descriptor *pgio,
 static void nfs_writeback_done_partial(struct rpc_task *task, void *calldata)
 {
 	struct nfs_write_data	*data = calldata;
-	struct nfs_page		*req = data->req;
 
-	dprintk("NFS: write (%s/%Ld %d@%Ld)",
-		req->wb_context->path.dentry->d_inode->i_sb->s_id,
-		(long long)NFS_FILEID(req->wb_context->path.dentry->d_inode),
-		req->wb_bytes,
-		(long long)req_offset(req));
+	dprintk("NFS: %5u write(%s/%lld %d@%lld)",
+		task->tk_pid,
+		data->req->wb_context->path.dentry->d_inode->i_sb->s_id,
+		(long long)
+		  NFS_FILEID(data->req->wb_context->path.dentry->d_inode),
+		data->req->wb_bytes, (long long)req_offset(data->req));
 
 	nfs_writeback_done(task, data);
 }
@@ -1058,7 +1057,8 @@ static void nfs_writeback_release_full(void *calldata)
 
 		nfs_list_remove_request(req);
 
-		dprintk("NFS: write (%s/%Ld %d@%Ld)",
+		dprintk("NFS: %5u write (%s/%lld %d@%lld)",
+			data->task.tk_pid,
 			req->wb_context->path.dentry->d_inode->i_sb->s_id,
 			(long long)NFS_FILEID(req->wb_context->path.dentry->d_inode),
 			req->wb_bytes,
@@ -1078,8 +1078,6 @@ static void nfs_writeback_release_full(void *calldata)
 			dprintk(" marked for commit\n");
 			goto next;
 		}
-		/* Set the PG_uptodate flag? */
-		nfs_mark_uptodate(page, req->wb_pgbase, req->wb_bytes);
 		dprintk(" OK\n");
 remove_request:
 		nfs_end_page_writeback(page);
@@ -1133,7 +1131,7 @@ int nfs_writeback_done(struct rpc_task *task, struct nfs_write_data *data)
 		static unsigned long    complain;
 
 		if (time_before(complain, jiffies)) {
-			dprintk("NFS: faulty NFS server %s:"
+			dprintk("NFS:       faulty NFS server %s:"
 				" (committed = %d) != (stable = %d)\n",
 				NFS_SERVER(data->inode)->nfs_client->cl_hostname,
 				resp->verf->committed, argp->stable);
@@ -1297,12 +1295,9 @@ static void nfs_commit_release(void *calldata)
 	while (!list_empty(&data->pages)) {
 		req = nfs_list_entry(data->pages.next);
 		nfs_list_remove_request(req);
-		clear_bit(PG_NEED_COMMIT, &(req)->wb_flags);
-		dec_zone_page_state(req->wb_page, NR_UNSTABLE_NFS);
-		dec_bdi_stat(req->wb_page->mapping->backing_dev_info,
-				BDI_RECLAIMABLE);
+		nfs_clear_request_commit(req);
 
-		dprintk("NFS: commit (%s/%Ld %d@%Ld)",
+		dprintk("NFS:       commit (%s/%lld %d@%lld)",
 			req->wb_context->path.dentry->d_inode->i_sb->s_id,
 			(long long)NFS_FILEID(req->wb_context->path.dentry->d_inode),
 			req->wb_bytes,
@@ -1318,9 +1313,6 @@ static void nfs_commit_release(void *calldata)
 		 * returned by the server against all stored verfs. */
 		if (!memcmp(req->wb_verf.verifier, data->verf.verifier, sizeof(data->verf.verifier))) {
 			/* We have a match */
-			/* Set the PG_uptodate flag */
-			nfs_mark_uptodate(req->wb_page, req->wb_pgbase,
-					req->wb_bytes);
 			nfs_inode_remove_request(req);
 			dprintk(" OK\n");
 			goto next;
@@ -1479,7 +1471,7 @@ int nfs_wb_page_cancel(struct inode *inode, struct page *page)
 		req = nfs_page_find_request(page);
 		if (req == NULL)
 			goto out;
-		if (test_bit(PG_NEED_COMMIT, &req->wb_flags)) {
+		if (test_bit(PG_CLEAN, &req->wb_flags)) {
 			nfs_release_request(req);
 			break;
 		}
diff --git a/fs/nfsd/nfs4callback.c b/fs/nfsd/nfs4callback.c
index 4d4760e687c..702fa577aa6 100644
--- a/fs/nfsd/nfs4callback.c
+++ b/fs/nfsd/nfs4callback.c
@@ -381,7 +381,7 @@ static int do_probe_callback(void *data)
 		.program	= &cb_program,
 		.version	= nfs_cb_version[1]->number,
 		.authflavor	= RPC_AUTH_UNIX, /* XXX: need AUTH_GSS... */
-		.flags		= (RPC_CLNT_CREATE_NOPING),
+		.flags		= (RPC_CLNT_CREATE_NOPING | RPC_CLNT_CREATE_QUIET),
 	};
 	struct rpc_message msg = {
 		.rpc_proc       = &nfs4_cb_procedures[NFSPROC4_CLNT_CB_NULL],
diff --git a/fs/ocfs2/aops.c b/fs/ocfs2/aops.c
index 17964c0505a..1db080135c6 100644
--- a/fs/ocfs2/aops.c
+++ b/fs/ocfs2/aops.c
@@ -174,10 +174,17 @@ static int ocfs2_get_block(struct inode *inode, sector_t iblock,
 	 * need to use BH_New is when we're extending i_size on a file
 	 * system which doesn't support holes, in which case BH_New
 	 * allows block_prepare_write() to zero.
+	 *
+	 * If we see this on a sparse file system, then a truncate has
+	 * raced us and removed the cluster. In this case, we clear
+	 * the buffers dirty and uptodate bits and let the buffer code
+	 * ignore it as a hole.
 	 */
-	mlog_bug_on_msg(create && p_blkno == 0 && ocfs2_sparse_alloc(osb),
-			"ino %lu, iblock %llu\n", inode->i_ino,
-			(unsigned long long)iblock);
+	if (create && p_blkno == 0 && ocfs2_sparse_alloc(osb)) {
+		clear_buffer_dirty(bh_result);
+		clear_buffer_uptodate(bh_result);
+		goto bail;
+	}
 
 	/* Treat the unwritten extent as a hole for zeroing purposes. */
 	if (p_blkno && !(ext_flags & OCFS2_EXT_UNWRITTEN))
diff --git a/fs/ocfs2/cluster/heartbeat.c b/fs/ocfs2/cluster/heartbeat.c
index f02ccb34604..443d108211a 100644
--- a/fs/ocfs2/cluster/heartbeat.c
+++ b/fs/ocfs2/cluster/heartbeat.c
@@ -1489,25 +1489,28 @@ static struct o2hb_heartbeat_group *to_o2hb_heartbeat_group(struct config_group
 		: NULL;
 }
 
-static struct config_item *o2hb_heartbeat_group_make_item(struct config_group *group,
-							  const char *name)
+static int o2hb_heartbeat_group_make_item(struct config_group *group,
+					  const char *name,
+					  struct config_item **new_item)
 {
 	struct o2hb_region *reg = NULL;
-	struct config_item *ret = NULL;
+	int ret = 0;
 
 	reg = kzalloc(sizeof(struct o2hb_region), GFP_KERNEL);
-	if (reg == NULL)
-		goto out; /* ENOMEM */
+	if (reg == NULL) {
+		ret = -ENOMEM;
+		goto out;
+	}
 
 	config_item_init_type_name(&reg->hr_item, name, &o2hb_region_type);
 
-	ret = &reg->hr_item;
+	*new_item = &reg->hr_item;
 
 	spin_lock(&o2hb_live_lock);
 	list_add_tail(&reg->hr_all_item, &o2hb_all_regions);
 	spin_unlock(&o2hb_live_lock);
 out:
-	if (ret == NULL)
+	if (ret)
 		kfree(reg);
 
 	return ret;
diff --git a/fs/ocfs2/cluster/netdebug.c b/fs/ocfs2/cluster/netdebug.c
index 7bf3c0ea7bd..d8bfa0eb41b 100644
--- a/fs/ocfs2/cluster/netdebug.c
+++ b/fs/ocfs2/cluster/netdebug.c
@@ -146,8 +146,10 @@ static int nst_seq_show(struct seq_file *seq, void *v)
 			   nst->st_task->comm, nst->st_node,
 			   nst->st_sc, nst->st_id, nst->st_msg_type,
 			   nst->st_msg_key,
-			   nst->st_sock_time.tv_sec, nst->st_sock_time.tv_usec,
-			   nst->st_send_time.tv_sec, nst->st_send_time.tv_usec,
+			   nst->st_sock_time.tv_sec,
+			   (unsigned long)nst->st_sock_time.tv_usec,
+			   nst->st_send_time.tv_sec,
+			   (unsigned long)nst->st_send_time.tv_usec,
 			   nst->st_status_time.tv_sec,
 			   nst->st_status_time.tv_usec);
 	}
@@ -274,7 +276,7 @@ static void *sc_seq_next(struct seq_file *seq, void *v, loff_t *pos)
 	return sc; /* unused, just needs to be null when done */
 }
 
-#define TV_SEC_USEC(TV) TV.tv_sec, TV.tv_usec
+#define TV_SEC_USEC(TV) TV.tv_sec, (unsigned long)TV.tv_usec
 
 static int sc_seq_show(struct seq_file *seq, void *v)
 {
diff --git a/fs/ocfs2/cluster/nodemanager.c b/fs/ocfs2/cluster/nodemanager.c
index cfdb08b484e..b364b7052e4 100644
--- a/fs/ocfs2/cluster/nodemanager.c
+++ b/fs/ocfs2/cluster/nodemanager.c
@@ -644,27 +644,32 @@ out:
 	return ret;
 }
 
-static struct config_item *o2nm_node_group_make_item(struct config_group *group,
-						     const char *name)
+static int o2nm_node_group_make_item(struct config_group *group,
+				     const char *name,
+				     struct config_item **new_item)
 {
 	struct o2nm_node *node = NULL;
-	struct config_item *ret = NULL;
+	int ret = 0;
 
-	if (strlen(name) > O2NM_MAX_NAME_LEN)
-		goto out; /* ENAMETOOLONG */
+	if (strlen(name) > O2NM_MAX_NAME_LEN) {
+		ret = -ENAMETOOLONG;
+		goto out;
+	}
 
 	node = kzalloc(sizeof(struct o2nm_node), GFP_KERNEL);
-	if (node == NULL)
-		goto out; /* ENOMEM */
+	if (node == NULL) {
+		ret = -ENOMEM;
+		goto out;
+	}
 
 	strcpy(node->nd_name, name); /* use item.ci_namebuf instead? */
 	config_item_init_type_name(&node->nd_item, name, &o2nm_node_type);
 	spin_lock_init(&node->nd_lock);
 
-	ret = &node->nd_item;
+	*new_item = &node->nd_item;
 
 out:
-	if (ret == NULL)
+	if (ret)
 		kfree(node);
 
 	return ret;
@@ -751,25 +756,31 @@ static struct o2nm_cluster_group *to_o2nm_cluster_group(struct config_group *gro
 }
 #endif
 
-static struct config_group *o2nm_cluster_group_make_group(struct config_group *group,
-							  const char *name)
+static int o2nm_cluster_group_make_group(struct config_group *group,
+					 const char *name,
+					 struct config_group **new_group)
 {
 	struct o2nm_cluster *cluster = NULL;
 	struct o2nm_node_group *ns = NULL;
-	struct config_group *o2hb_group = NULL, *ret = NULL;
+	struct config_group *o2hb_group = NULL;
 	void *defs = NULL;
+	int ret = 0;
 
 	/* this runs under the parent dir's i_mutex; there can be only
 	 * one caller in here at a time */
-	if (o2nm_single_cluster)
-		goto out; /* ENOSPC */
+	if (o2nm_single_cluster) {
+		ret = -ENOSPC;
+		goto out;
+	}
 
 	cluster = kzalloc(sizeof(struct o2nm_cluster), GFP_KERNEL);
 	ns = kzalloc(sizeof(struct o2nm_node_group), GFP_KERNEL);
 	defs = kcalloc(3, sizeof(struct config_group *), GFP_KERNEL);
 	o2hb_group = o2hb_alloc_hb_set();
-	if (cluster == NULL || ns == NULL || o2hb_group == NULL || defs == NULL)
+	if (cluster == NULL || ns == NULL || o2hb_group == NULL || defs == NULL) {
+		ret = -ENOMEM;
 		goto out;
+	}
 
 	config_group_init_type_name(&cluster->cl_group, name,
 				    &o2nm_cluster_type);
@@ -786,11 +797,11 @@ static struct config_group *o2nm_cluster_group_make_group(struct config_group *g
 	cluster->cl_idle_timeout_ms    = O2NET_IDLE_TIMEOUT_MS_DEFAULT;
 	cluster->cl_keepalive_delay_ms = O2NET_KEEPALIVE_DELAY_MS_DEFAULT;
 
-	ret = &cluster->cl_group;
+	*new_group = &cluster->cl_group;
 	o2nm_single_cluster = cluster;
 
 out:
-	if (ret == NULL) {
+	if (ret) {
 		kfree(cluster);
 		kfree(ns);
 		o2hb_free_hb_set(o2hb_group);
diff --git a/fs/ocfs2/dlm/dlmmaster.c b/fs/ocfs2/dlm/dlmmaster.c
index efc015c6128..44f87caf368 100644
--- a/fs/ocfs2/dlm/dlmmaster.c
+++ b/fs/ocfs2/dlm/dlmmaster.c
@@ -606,7 +606,9 @@ static void dlm_init_lockres(struct dlm_ctxt *dlm,
 
 	res->last_used = 0;
 
+	spin_lock(&dlm->spinlock);
 	list_add_tail(&res->tracking, &dlm->tracking_list);
+	spin_unlock(&dlm->spinlock);
 
 	memset(res->lvb, 0, DLM_LVB_LEN);
 	memset(res->refmap, 0, sizeof(res->refmap));
diff --git a/fs/ocfs2/dlmglue.c b/fs/ocfs2/dlmglue.c
index 394d25a131a..eae3d643a5e 100644
--- a/fs/ocfs2/dlmglue.c
+++ b/fs/ocfs2/dlmglue.c
@@ -31,6 +31,7 @@
 #include <linux/pagemap.h>
 #include <linux/debugfs.h>
 #include <linux/seq_file.h>
+#include <linux/time.h>
 
 #define MLOG_MASK_PREFIX ML_DLM_GLUE
 #include <cluster/masklog.h>
@@ -59,6 +60,9 @@ struct ocfs2_mask_waiter {
 	struct completion	mw_complete;
 	unsigned long		mw_mask;
 	unsigned long		mw_goal;
+#ifdef CONFIG_OCFS2_FS_STATS
+	unsigned long long 	mw_lock_start;
+#endif
 };
 
 static struct ocfs2_super *ocfs2_get_dentry_osb(struct ocfs2_lock_res *lockres);
@@ -366,6 +370,75 @@ static void ocfs2_remove_lockres_tracking(struct ocfs2_lock_res *res)
 	spin_unlock(&ocfs2_dlm_tracking_lock);
 }
 
+#ifdef CONFIG_OCFS2_FS_STATS
+static void ocfs2_init_lock_stats(struct ocfs2_lock_res *res)
+{
+	res->l_lock_num_prmode = 0;
+	res->l_lock_num_prmode_failed = 0;
+	res->l_lock_total_prmode = 0;
+	res->l_lock_max_prmode = 0;
+	res->l_lock_num_exmode = 0;
+	res->l_lock_num_exmode_failed = 0;
+	res->l_lock_total_exmode = 0;
+	res->l_lock_max_exmode = 0;
+	res->l_lock_refresh = 0;
+}
+
+static void ocfs2_update_lock_stats(struct ocfs2_lock_res *res, int level,
+				    struct ocfs2_mask_waiter *mw, int ret)
+{
+	unsigned long long *num, *sum;
+	unsigned int *max, *failed;
+	struct timespec ts = current_kernel_time();
+	unsigned long long time = timespec_to_ns(&ts) - mw->mw_lock_start;
+
+	if (level == LKM_PRMODE) {
+		num = &res->l_lock_num_prmode;
+		sum = &res->l_lock_total_prmode;
+		max = &res->l_lock_max_prmode;
+		failed = &res->l_lock_num_prmode_failed;
+	} else if (level == LKM_EXMODE) {
+		num = &res->l_lock_num_exmode;
+		sum = &res->l_lock_total_exmode;
+		max = &res->l_lock_max_exmode;
+		failed = &res->l_lock_num_exmode_failed;
+	} else
+		return;
+
+	(*num)++;
+	(*sum) += time;
+	if (time > *max)
+		*max = time;
+	if (ret)
+		(*failed)++;
+}
+
+static inline void ocfs2_track_lock_refresh(struct ocfs2_lock_res *lockres)
+{
+	lockres->l_lock_refresh++;
+}
+
+static inline void ocfs2_init_start_time(struct ocfs2_mask_waiter *mw)
+{
+	struct timespec ts = current_kernel_time();
+	mw->mw_lock_start = timespec_to_ns(&ts);
+}
+#else
+static inline void ocfs2_init_lock_stats(struct ocfs2_lock_res *res)
+{
+}
+static inline void ocfs2_update_lock_stats(struct ocfs2_lock_res *res,
+			   int level, struct ocfs2_mask_waiter *mw, int ret)
+{
+}
+static inline void ocfs2_track_lock_refresh(struct ocfs2_lock_res *lockres)
+{
+}
+static inline void ocfs2_init_start_time(struct ocfs2_mask_waiter *mw)
+{
+}
+#endif
+
 static void ocfs2_lock_res_init_common(struct ocfs2_super *osb,
 				       struct ocfs2_lock_res *res,
 				       enum ocfs2_lock_type type,
@@ -385,6 +458,8 @@ static void ocfs2_lock_res_init_common(struct ocfs2_super *osb,
 	res->l_flags         = OCFS2_LOCK_INITIALIZED;
 
 	ocfs2_add_lockres_tracking(res, osb->osb_dlm_debug);
+
+	ocfs2_init_lock_stats(res);
 }
 
 void ocfs2_lock_res_init_once(struct ocfs2_lock_res *res)
@@ -1048,6 +1123,7 @@ static void ocfs2_init_mask_waiter(struct ocfs2_mask_waiter *mw)
 {
 	INIT_LIST_HEAD(&mw->mw_item);
 	init_completion(&mw->mw_complete);
+	ocfs2_init_start_time(mw);
 }
 
 static int ocfs2_wait_for_mask(struct ocfs2_mask_waiter *mw)
@@ -1254,6 +1330,7 @@ out:
 			goto again;
 		mlog_errno(ret);
 	}
+	ocfs2_update_lock_stats(lockres, level, &mw, ret);
 
 	mlog_exit(ret);
 	return ret;
@@ -1554,8 +1631,8 @@ out:
  */
 int ocfs2_file_lock(struct file *file, int ex, int trylock)
 {
-	int ret, level = ex ? LKM_EXMODE : LKM_PRMODE;
-	unsigned int lkm_flags = trylock ? LKM_NOQUEUE : 0;
+	int ret, level = ex ? DLM_LOCK_EX : DLM_LOCK_PR;
+	unsigned int lkm_flags = trylock ? DLM_LKF_NOQUEUE : 0;
 	unsigned long flags;
 	struct ocfs2_file_private *fp = file->private_data;
 	struct ocfs2_lock_res *lockres = &fp->fp_flock;
@@ -1582,7 +1659,7 @@ int ocfs2_file_lock(struct file *file, int ex, int trylock)
 		 * Get the lock at NLMODE to start - that way we
 		 * can cancel the upconvert request if need be.
 		 */
-		ret = ocfs2_lock_create(osb, lockres, LKM_NLMODE, 0);
+		ret = ocfs2_lock_create(osb, lockres, DLM_LOCK_NL, 0);
 		if (ret < 0) {
 			mlog_errno(ret);
 			goto out;
@@ -1597,7 +1674,7 @@ int ocfs2_file_lock(struct file *file, int ex, int trylock)
 	}
 
 	lockres->l_action = OCFS2_AST_CONVERT;
-	lkm_flags |= LKM_CONVERT;
+	lkm_flags |= DLM_LKF_CONVERT;
 	lockres->l_requested = level;
 	lockres_or_flags(lockres, OCFS2_LOCK_BUSY);
 
@@ -1664,7 +1741,7 @@ void ocfs2_file_unlock(struct file *file)
 	if (!(lockres->l_flags & OCFS2_LOCK_ATTACHED))
 		return;
 
-	if (lockres->l_level == LKM_NLMODE)
+	if (lockres->l_level == DLM_LOCK_NL)
 		return;
 
 	mlog(0, "Unlock: \"%s\" flags: 0x%lx, level: %d, act: %d\n",
@@ -1678,11 +1755,11 @@ void ocfs2_file_unlock(struct file *file)
 	lockres_or_flags(lockres, OCFS2_LOCK_BLOCKED);
 	lockres->l_blocking = DLM_LOCK_EX;
 
-	gen = ocfs2_prepare_downconvert(lockres, LKM_NLMODE);
+	gen = ocfs2_prepare_downconvert(lockres, DLM_LOCK_NL);
 	lockres_add_mask_waiter(lockres, &mw, OCFS2_LOCK_BUSY, 0);
 	spin_unlock_irqrestore(&lockres->l_lock, flags);
 
-	ret = ocfs2_downconvert_lock(osb, lockres, LKM_NLMODE, 0, gen);
+	ret = ocfs2_downconvert_lock(osb, lockres, DLM_LOCK_NL, 0, gen);
 	if (ret) {
 		mlog_errno(ret);
 		return;
@@ -1983,6 +2060,7 @@ static int ocfs2_inode_lock_update(struct inode *inode,
 				le32_to_cpu(fe->i_flags));
 
 		ocfs2_refresh_inode(inode, fe);
+		ocfs2_track_lock_refresh(lockres);
 	}
 
 	status = 0;
@@ -2267,6 +2345,7 @@ int ocfs2_super_lock(struct ocfs2_super *osb,
 
 		if (status < 0)
 			mlog_errno(status);
+		ocfs2_track_lock_refresh(lockres);
 	}
 bail:
 	mlog_exit(status);
@@ -2461,7 +2540,7 @@ static void *ocfs2_dlm_seq_next(struct seq_file *m, void *v, loff_t *pos)
 }
 
 /* So that debugfs.ocfs2 can determine which format is being used */
-#define OCFS2_DLM_DEBUG_STR_VERSION 1
+#define OCFS2_DLM_DEBUG_STR_VERSION 2
 static int ocfs2_dlm_seq_show(struct seq_file *m, void *v)
 {
 	int i;
@@ -2502,6 +2581,47 @@ static int ocfs2_dlm_seq_show(struct seq_file *m, void *v)
 	for(i = 0; i < DLM_LVB_LEN; i++)
 		seq_printf(m, "0x%x\t", lvb[i]);
 
+#ifdef CONFIG_OCFS2_FS_STATS
+# define lock_num_prmode(_l)		(_l)->l_lock_num_prmode
+# define lock_num_exmode(_l)		(_l)->l_lock_num_exmode
+# define lock_num_prmode_failed(_l)	(_l)->l_lock_num_prmode_failed
+# define lock_num_exmode_failed(_l)	(_l)->l_lock_num_exmode_failed
+# define lock_total_prmode(_l)		(_l)->l_lock_total_prmode
+# define lock_total_exmode(_l)		(_l)->l_lock_total_exmode
+# define lock_max_prmode(_l)		(_l)->l_lock_max_prmode
+# define lock_max_exmode(_l)		(_l)->l_lock_max_exmode
+# define lock_refresh(_l)		(_l)->l_lock_refresh
+#else
+# define lock_num_prmode(_l)		(0ULL)
+# define lock_num_exmode(_l)		(0ULL)
+# define lock_num_prmode_failed(_l)	(0)
+# define lock_num_exmode_failed(_l)	(0)
+# define lock_total_prmode(_l)		(0ULL)
+# define lock_total_exmode(_l)		(0ULL)
+# define lock_max_prmode(_l)		(0)
+# define lock_max_exmode(_l)		(0)
+# define lock_refresh(_l)		(0)
+#endif
+	/* The following seq_print was added in version 2 of this output */
+	seq_printf(m, "%llu\t"
+		   "%llu\t"
+		   "%u\t"
+		   "%u\t"
+		   "%llu\t"
+		   "%llu\t"
+		   "%u\t"
+		   "%u\t"
+		   "%u\t",
+		   lock_num_prmode(lockres),
+		   lock_num_exmode(lockres),
+		   lock_num_prmode_failed(lockres),
+		   lock_num_exmode_failed(lockres),
+		   lock_total_prmode(lockres),
+		   lock_total_exmode(lockres),
+		   lock_max_prmode(lockres),
+		   lock_max_exmode(lockres),
+		   lock_refresh(lockres));
+
 	/* End the line */
 	seq_printf(m, "\n");
 	return 0;
diff --git a/fs/ocfs2/file.c b/fs/ocfs2/file.c
index 57e0d30cde9..e8514e8b6ce 100644
--- a/fs/ocfs2/file.c
+++ b/fs/ocfs2/file.c
@@ -2202,7 +2202,7 @@ static ssize_t ocfs2_file_aio_read(struct kiocb *iocb,
 
 	ret = generic_file_aio_read(iocb, iov, nr_segs, iocb->ki_pos);
 	if (ret == -EINVAL)
-		mlog(ML_ERROR, "generic_file_aio_read returned -EINVAL\n");
+		mlog(0, "generic_file_aio_read returned -EINVAL\n");
 
 	/* buffered aio wouldn't have proper lock coverage today */
 	BUG_ON(ret == -EIOCBQUEUED && !(filp->f_flags & O_DIRECT));
diff --git a/fs/ocfs2/journal.c b/fs/ocfs2/journal.c
index 9698338adc3..a8c19cb3cfd 100644
--- a/fs/ocfs2/journal.c
+++ b/fs/ocfs2/journal.c
@@ -329,7 +329,7 @@ int ocfs2_extend_trans(handle_t *handle, int nblocks)
 
 	mlog(0, "Trying to extend transaction by %d blocks\n", nblocks);
 
-#ifdef OCFS2_DEBUG_FS
+#ifdef CONFIG_OCFS2_DEBUG_FS
 	status = 1;
 #else
 	status = journal_extend(handle, nblocks);
diff --git a/fs/ocfs2/localalloc.c b/fs/ocfs2/localalloc.c
index be774bdc8b3..28e492e4ec8 100644
--- a/fs/ocfs2/localalloc.c
+++ b/fs/ocfs2/localalloc.c
@@ -498,7 +498,7 @@ int ocfs2_reserve_local_alloc_bits(struct ocfs2_super *osb,
 
 	alloc = (struct ocfs2_dinode *) osb->local_alloc_bh->b_data;
 
-#ifdef OCFS2_DEBUG_FS
+#ifdef CONFIG_OCFS2_DEBUG_FS
 	if (le32_to_cpu(alloc->id1.bitmap1.i_used) !=
 	    ocfs2_local_alloc_count_bits(alloc)) {
 		ocfs2_error(osb->sb, "local alloc inode %llu says it has "
diff --git a/fs/ocfs2/ocfs2.h b/fs/ocfs2/ocfs2.h
index 31692379c17..1cb814be8ef 100644
--- a/fs/ocfs2/ocfs2.h
+++ b/fs/ocfs2/ocfs2.h
@@ -132,6 +132,18 @@ struct ocfs2_lock_res {
 	wait_queue_head_t        l_event;
 
 	struct list_head         l_debug_list;
+
+#ifdef CONFIG_OCFS2_FS_STATS
+	unsigned long long	 l_lock_num_prmode; 	   /* PR acquires */
+	unsigned long long 	 l_lock_num_exmode; 	   /* EX acquires */
+	unsigned int		 l_lock_num_prmode_failed; /* Failed PR gets */
+	unsigned int		 l_lock_num_exmode_failed; /* Failed EX gets */
+	unsigned long long	 l_lock_total_prmode; 	   /* Tot wait for PR */
+	unsigned long long	 l_lock_total_exmode; 	   /* Tot wait for EX */
+	unsigned int		 l_lock_max_prmode; 	   /* Max wait for PR */
+	unsigned int		 l_lock_max_exmode; 	   /* Max wait for EX */
+	unsigned int		 l_lock_refresh;	   /* Disk refreshes */
+#endif
 };
 
 struct ocfs2_dlm_debug {
diff --git a/fs/ocfs2/ocfs2_fs.h b/fs/ocfs2/ocfs2_fs.h
index 52c42666515..3f194517762 100644
--- a/fs/ocfs2/ocfs2_fs.h
+++ b/fs/ocfs2/ocfs2_fs.h
@@ -901,7 +901,7 @@ static inline int ocfs2_sprintf_system_inode_name(char *buf, int len,
          * list has a copy per slot.
          */
 	if (type <= OCFS2_LAST_GLOBAL_SYSTEM_INODE)
-		chars = snprintf(buf, len,
+		chars = snprintf(buf, len, "%s",
 				 ocfs2_system_inodes[type].si_name);
 	else
 		chars = snprintf(buf, len,
diff --git a/fs/ocfs2/stack_user.c b/fs/ocfs2/stack_user.c
index c021280dd46..353fc35c674 100644
--- a/fs/ocfs2/stack_user.c
+++ b/fs/ocfs2/stack_user.c
@@ -21,6 +21,7 @@
 #include <linux/fs.h>
 #include <linux/miscdevice.h>
 #include <linux/mutex.h>
+#include <linux/smp_lock.h>
 #include <linux/reboot.h>
 #include <asm/uaccess.h>
 
@@ -549,26 +550,17 @@ static ssize_t ocfs2_control_read(struct file *file,
 				  size_t count,
 				  loff_t *ppos)
 {
-	char *proto_string = OCFS2_CONTROL_PROTO;
-	size_t to_write = 0;
-
-	if (*ppos >= OCFS2_CONTROL_PROTO_LEN)
-		return 0;
-
-	to_write = OCFS2_CONTROL_PROTO_LEN - *ppos;
-	if (to_write > count)
-		to_write = count;
-	if (copy_to_user(buf, proto_string + *ppos, to_write))
-		return -EFAULT;
+	ssize_t ret;
 
-	*ppos += to_write;
+	ret = simple_read_from_buffer(buf, count, ppos,
+			OCFS2_CONTROL_PROTO, OCFS2_CONTROL_PROTO_LEN);
 
 	/* Have we read the whole protocol list? */
-	if (*ppos >= OCFS2_CONTROL_PROTO_LEN)
+	if (ret > 0 && *ppos >= OCFS2_CONTROL_PROTO_LEN)
 		ocfs2_control_set_handshake_state(file,
 						  OCFS2_CONTROL_HANDSHAKE_READ);
 
-	return to_write;
+	return ret;
 }
 
 static int ocfs2_control_release(struct inode *inode, struct file *file)
@@ -619,10 +611,12 @@ static int ocfs2_control_open(struct inode *inode, struct file *file)
 		return -ENOMEM;
 	p->op_this_node = -1;
 
+	lock_kernel();
 	mutex_lock(&ocfs2_control_lock);
 	file->private_data = p;
 	list_add(&p->op_list, &ocfs2_control_private_list);
 	mutex_unlock(&ocfs2_control_lock);
+	unlock_kernel();
 
 	return 0;
 }
diff --git a/fs/ocfs2/super.c b/fs/ocfs2/super.c
index df63ba20ae9..ccecfe5094f 100644
--- a/fs/ocfs2/super.c
+++ b/fs/ocfs2/super.c
@@ -1703,7 +1703,11 @@ static int ocfs2_check_volume(struct ocfs2_super *osb)
 	local = ocfs2_mount_local(osb);
 
 	/* will play back anything left in the journal. */
-	ocfs2_journal_load(osb->journal, local);
+	status = ocfs2_journal_load(osb->journal, local);
+	if (status < 0) {
+		mlog(ML_ERROR, "ocfs2 journal load failed! %d\n", status);
+		goto finally;
+	}
 
 	if (dirty) {
 		/* recover my local alloc if we didn't unmount cleanly. */
diff --git a/fs/open.c b/fs/open.c
index a1450086e92..a99ad09c319 100644
--- a/fs/open.c
+++ b/fs/open.c
@@ -16,6 +16,7 @@
 #include <linux/namei.h>
 #include <linux/backing-dev.h>
 #include <linux/capability.h>
+#include <linux/securebits.h>
 #include <linux/security.h>
 #include <linux/mount.h>
 #include <linux/vfs.h>
@@ -425,7 +426,7 @@ asmlinkage long sys_faccessat(int dfd, const char __user *filename, int mode)
 {
 	struct nameidata nd;
 	int old_fsuid, old_fsgid;
-	kernel_cap_t old_cap;
+	kernel_cap_t uninitialized_var(old_cap);  /* !SECURE_NO_SETUID_FIXUP */
 	int res;
 
 	if (mode & ~S_IRWXO)	/* where's F_OK, X_OK, W_OK, R_OK? */
@@ -433,23 +434,27 @@ asmlinkage long sys_faccessat(int dfd, const char __user *filename, int mode)
 
 	old_fsuid = current->fsuid;
 	old_fsgid = current->fsgid;
-	old_cap = current->cap_effective;
 
 	current->fsuid = current->uid;
 	current->fsgid = current->gid;
 
-	/*
-	 * Clear the capabilities if we switch to a non-root user
-	 *
-	 * FIXME: There is a race here against sys_capset.  The
-	 * capabilities can change yet we will restore the old
-	 * value below.  We should hold task_capabilities_lock,
-	 * but we cannot because user_path_walk can sleep.
-	 */
-	if (current->uid)
-		cap_clear(current->cap_effective);
-	else
-		current->cap_effective = current->cap_permitted;
+	if (!issecure(SECURE_NO_SETUID_FIXUP)) {
+		/*
+		 * Clear the capabilities if we switch to a non-root user
+		 */
+#ifndef CONFIG_SECURITY_FILE_CAPABILITIES
+		/*
+		 * FIXME: There is a race here against sys_capset.  The
+		 * capabilities can change yet we will restore the old
+		 * value below.  We should hold task_capabilities_lock,
+		 * but we cannot because user_path_walk can sleep.
+		 */
+#endif /* ndef CONFIG_SECURITY_FILE_CAPABILITIES */
+		if (current->uid)
+			old_cap = cap_set_effective(__cap_empty_set);
+		else
+			old_cap = cap_set_effective(current->cap_permitted);
+	}
 
 	res = __user_walk_fd(dfd, filename, LOOKUP_FOLLOW|LOOKUP_ACCESS, &nd);
 	if (res)
@@ -478,7 +483,9 @@ out_path_release:
 out:
 	current->fsuid = old_fsuid;
 	current->fsgid = old_fsgid;
-	current->cap_effective = old_cap;
+
+	if (!issecure(SECURE_NO_SETUID_FIXUP))
+		cap_set_effective(old_cap);
 
 	return res;
 }
diff --git a/fs/proc/base.c b/fs/proc/base.c
index 3b455371e7f..58c3e6a8e15 100644
--- a/fs/proc/base.c
+++ b/fs/proc/base.c
@@ -233,7 +233,7 @@ static int check_mem_permission(struct task_struct *task)
 	 */
 	if (task->parent == current && (task->ptrace & PT_PTRACED) &&
 	    task_is_stopped_or_traced(task) &&
-	    ptrace_may_attach(task))
+	    ptrace_may_access(task, PTRACE_MODE_ATTACH))
 		return 0;
 
 	/*
@@ -251,7 +251,8 @@ struct mm_struct *mm_for_maps(struct task_struct *task)
 	task_lock(task);
 	if (task->mm != mm)
 		goto out;
-	if (task->mm != current->mm && __ptrace_may_attach(task) < 0)
+	if (task->mm != current->mm &&
+	    __ptrace_may_access(task, PTRACE_MODE_READ) < 0)
 		goto out;
 	task_unlock(task);
 	return mm;
@@ -518,7 +519,7 @@ static int proc_fd_access_allowed(struct inode *inode)
 	 */
 	task = get_proc_task(inode);
 	if (task) {
-		allowed = ptrace_may_attach(task);
+		allowed = ptrace_may_access(task, PTRACE_MODE_READ);
 		put_task_struct(task);
 	}
 	return allowed;
@@ -904,7 +905,7 @@ static ssize_t environ_read(struct file *file, char __user *buf,
 	if (!task)
 		goto out_no_task;
 
-	if (!ptrace_may_attach(task))
+	if (!ptrace_may_access(task, PTRACE_MODE_READ))
 		goto out;
 
 	ret = -ENOMEM;
diff --git a/fs/proc/proc_misc.c b/fs/proc/proc_misc.c
index 7e277f2ad46..c652d469dc0 100644
--- a/fs/proc/proc_misc.c
+++ b/fs/proc/proc_misc.c
@@ -123,6 +123,11 @@ static int uptime_read_proc(char *page, char **start, off_t off,
 	return proc_calc_metrics(page, start, off, count, eof, len);
 }
 
+int __attribute__((weak)) arch_report_meminfo(char *page)
+{
+	return 0;
+}
+
 static int meminfo_read_proc(char *page, char **start, off_t off,
 				 int count, int *eof, void *data)
 {
@@ -221,6 +226,8 @@ static int meminfo_read_proc(char *page, char **start, off_t off,
 
 		len += hugetlb_report_meminfo(page + len);
 
+	len += arch_report_meminfo(page + len);
+
 	return proc_calc_metrics(page, start, off, count, eof, len);
 #undef K
 }
@@ -472,6 +479,13 @@ static const struct file_operations proc_vmalloc_operations = {
 };
 #endif
 
+#ifndef arch_irq_stat_cpu
+#define arch_irq_stat_cpu(cpu) 0
+#endif
+#ifndef arch_irq_stat
+#define arch_irq_stat() 0
+#endif
+
 static int show_stat(struct seq_file *p, void *v)
 {
 	int i;
@@ -509,7 +523,9 @@ static int show_stat(struct seq_file *p, void *v)
 			sum += temp;
 			per_irq_sum[j] += temp;
 		}
+		sum += arch_irq_stat_cpu(i);
 	}
+	sum += arch_irq_stat();
 
 	seq_printf(p, "cpu  %llu %llu %llu %llu %llu %llu %llu %llu %llu\n",
 		(unsigned long long)cputime64_to_clock_t(user),
diff --git a/fs/proc/task_mmu.c b/fs/proc/task_mmu.c
index ab8ccc9d14f..164bd9f9ede 100644
--- a/fs/proc/task_mmu.c
+++ b/fs/proc/task_mmu.c
@@ -210,7 +210,7 @@ static int show_map(struct seq_file *m, void *v)
 	dev_t dev = 0;
 	int len;
 
-	if (maps_protect && !ptrace_may_attach(task))
+	if (maps_protect && !ptrace_may_access(task, PTRACE_MODE_READ))
 		return -EACCES;
 
 	if (file) {
@@ -476,10 +476,10 @@ static ssize_t clear_refs_write(struct file *file, const char __user *buf,
 		return -ESRCH;
 	mm = get_task_mm(task);
 	if (mm) {
-		static struct mm_walk clear_refs_walk;
-		memset(&clear_refs_walk, 0, sizeof(clear_refs_walk));
-		clear_refs_walk.pmd_entry = clear_refs_pte_range;
-		clear_refs_walk.mm = mm;
+		struct mm_walk clear_refs_walk = {
+			.pmd_entry = clear_refs_pte_range,
+			.mm = mm,
+		};
 		down_read(&mm->mmap_sem);
 		for (vma = mm->mmap; vma; vma = vma->vm_next) {
 			clear_refs_walk.private = vma;
@@ -602,11 +602,6 @@ static int pagemap_pte_range(pmd_t *pmd, unsigned long addr, unsigned long end,
 	return err;
 }
 
-static struct mm_walk pagemap_walk = {
-	.pmd_entry = pagemap_pte_range,
-	.pte_hole = pagemap_pte_hole
-};
-
 /*
  * /proc/pid/pagemap - an array mapping virtual pages to pfns
  *
@@ -641,12 +636,17 @@ static ssize_t pagemap_read(struct file *file, char __user *buf,
 	struct pagemapread pm;
 	int pagecount;
 	int ret = -ESRCH;
+	struct mm_walk pagemap_walk;
+	unsigned long src;
+	unsigned long svpfn;
+	unsigned long start_vaddr;
+	unsigned long end_vaddr;
 
 	if (!task)
 		goto out;
 
 	ret = -EACCES;
-	if (!ptrace_may_attach(task))
+	if (!ptrace_may_access(task, PTRACE_MODE_READ))
 		goto out_task;
 
 	ret = -EINVAL;
@@ -659,11 +659,15 @@ static ssize_t pagemap_read(struct file *file, char __user *buf,
 	if (!mm)
 		goto out_task;
 
-	ret = -ENOMEM;
+
 	uaddr = (unsigned long)buf & PAGE_MASK;
 	uend = (unsigned long)(buf + count);
 	pagecount = (PAGE_ALIGN(uend) - uaddr) / PAGE_SIZE;
-	pages = kmalloc(pagecount * sizeof(struct page *), GFP_KERNEL);
+	ret = 0;
+	if (pagecount == 0)
+		goto out_mm;
+	pages = kcalloc(pagecount, sizeof(struct page *), GFP_KERNEL);
+	ret = -ENOMEM;
 	if (!pages)
 		goto out_mm;
 
@@ -684,33 +688,33 @@ static ssize_t pagemap_read(struct file *file, char __user *buf,
 	pm.out = (u64 *)buf;
 	pm.end = (u64 *)(buf + count);
 
-	if (!ptrace_may_attach(task)) {
-		ret = -EIO;
-	} else {
-		unsigned long src = *ppos;
-		unsigned long svpfn = src / PM_ENTRY_BYTES;
-		unsigned long start_vaddr = svpfn << PAGE_SHIFT;
-		unsigned long end_vaddr = TASK_SIZE_OF(task);
-
-		/* watch out for wraparound */
-		if (svpfn > TASK_SIZE_OF(task) >> PAGE_SHIFT)
-			start_vaddr = end_vaddr;
-
-		/*
-		 * The odds are that this will stop walking way
-		 * before end_vaddr, because the length of the
-		 * user buffer is tracked in "pm", and the walk
-		 * will stop when we hit the end of the buffer.
-		 */
-		ret = walk_page_range(start_vaddr, end_vaddr,
-					&pagemap_walk);
-		if (ret == PM_END_OF_BUFFER)
-			ret = 0;
-		/* don't need mmap_sem for these, but this looks cleaner */
-		*ppos += (char *)pm.out - buf;
-		if (!ret)
-			ret = (char *)pm.out - buf;
-	}
+	pagemap_walk.pmd_entry = pagemap_pte_range;
+	pagemap_walk.pte_hole = pagemap_pte_hole;
+	pagemap_walk.mm = mm;
+	pagemap_walk.private = &pm;
+
+	src = *ppos;
+	svpfn = src / PM_ENTRY_BYTES;
+	start_vaddr = svpfn << PAGE_SHIFT;
+	end_vaddr = TASK_SIZE_OF(task);
+
+	/* watch out for wraparound */
+	if (svpfn > TASK_SIZE_OF(task) >> PAGE_SHIFT)
+		start_vaddr = end_vaddr;
+
+	/*
+	 * The odds are that this will stop walking way
+	 * before end_vaddr, because the length of the
+	 * user buffer is tracked in "pm", and the walk
+	 * will stop when we hit the end of the buffer.
+	 */
+	ret = walk_page_range(start_vaddr, end_vaddr, &pagemap_walk);
+	if (ret == PM_END_OF_BUFFER)
+		ret = 0;
+	/* don't need mmap_sem for these, but this looks cleaner */
+	*ppos += (char *)pm.out - buf;
+	if (!ret)
+		ret = (char *)pm.out - buf;
 
 out_pages:
 	for (; pagecount; pagecount--) {
@@ -743,7 +747,7 @@ static int show_numa_map_checked(struct seq_file *m, void *v)
 	struct proc_maps_private *priv = m->private;
 	struct task_struct *task = priv->task;
 
-	if (maps_protect && !ptrace_may_attach(task))
+	if (maps_protect && !ptrace_may_access(task, PTRACE_MODE_READ))
 		return -EACCES;
 
 	return show_numa_map(m, v);
diff --git a/fs/proc/task_nommu.c b/fs/proc/task_nommu.c
index 4b4f9cc2f18..5d84e7121df 100644
--- a/fs/proc/task_nommu.c
+++ b/fs/proc/task_nommu.c
@@ -113,7 +113,7 @@ static int show_map(struct seq_file *m, void *_vml)
 	struct proc_maps_private *priv = m->private;
 	struct task_struct *task = priv->task;
 
-	if (maps_protect && !ptrace_may_attach(task))
+	if (maps_protect && !ptrace_may_access(task, PTRACE_MODE_READ))
 		return -EACCES;
 
 	return nommu_vma_show(m, vml->vma);
diff --git a/fs/ramfs/file-mmu.c b/fs/ramfs/file-mmu.c
index 9590b902430..78f613cb9c7 100644
--- a/fs/ramfs/file-mmu.c
+++ b/fs/ramfs/file-mmu.c
@@ -45,6 +45,7 @@ const struct file_operations ramfs_file_operations = {
 	.mmap		= generic_file_mmap,
 	.fsync		= simple_sync_file,
 	.splice_read	= generic_file_splice_read,
+	.splice_write	= generic_file_splice_write,
 	.llseek		= generic_file_llseek,
 };
 
diff --git a/fs/ramfs/file-nommu.c b/fs/ramfs/file-nommu.c
index 0989bc2c2f6..52312ec93ff 100644
--- a/fs/ramfs/file-nommu.c
+++ b/fs/ramfs/file-nommu.c
@@ -43,6 +43,7 @@ const struct file_operations ramfs_file_operations = {
 	.aio_write		= generic_file_aio_write,
 	.fsync			= simple_sync_file,
 	.splice_read		= generic_file_splice_read,
+	.splice_write		= generic_file_splice_write,
 	.llseek			= generic_file_llseek,
 };
 
diff --git a/fs/read_write.c b/fs/read_write.c
index f0d1240a5c6..9ba495d5a29 100644
--- a/fs/read_write.c
+++ b/fs/read_write.c
@@ -31,12 +31,12 @@ const struct file_operations generic_ro_fops = {
 
 EXPORT_SYMBOL(generic_ro_fops);
 
-loff_t generic_file_llseek(struct file *file, loff_t offset, int origin)
+loff_t
+generic_file_llseek_unlocked(struct file *file, loff_t offset, int origin)
 {
 	loff_t retval;
 	struct inode *inode = file->f_mapping->host;
 
-	mutex_lock(&inode->i_mutex);
 	switch (origin) {
 		case SEEK_END:
 			offset += inode->i_size;
@@ -46,42 +46,26 @@ loff_t generic_file_llseek(struct file *file, loff_t offset, int origin)
 	}
 	retval = -EINVAL;
 	if (offset>=0 && offset<=inode->i_sb->s_maxbytes) {
+		/* Special lock needed here? */
 		if (offset != file->f_pos) {
 			file->f_pos = offset;
 			file->f_version = 0;
 		}
 		retval = offset;
 	}
-	mutex_unlock(&inode->i_mutex);
 	return retval;
 }
+EXPORT_SYMBOL(generic_file_llseek_unlocked);
 
-EXPORT_SYMBOL(generic_file_llseek);
-
-loff_t remote_llseek(struct file *file, loff_t offset, int origin)
+loff_t generic_file_llseek(struct file *file, loff_t offset, int origin)
 {
-	loff_t retval;
-
-	lock_kernel();
-	switch (origin) {
-		case SEEK_END:
-			offset += i_size_read(file->f_path.dentry->d_inode);
-			break;
-		case SEEK_CUR:
-			offset += file->f_pos;
-	}
-	retval = -EINVAL;
-	if (offset>=0 && offset<=file->f_path.dentry->d_inode->i_sb->s_maxbytes) {
-		if (offset != file->f_pos) {
-			file->f_pos = offset;
-			file->f_version = 0;
-		}
-		retval = offset;
-	}
-	unlock_kernel();
-	return retval;
+	loff_t n;
+	mutex_lock(&file->f_dentry->d_inode->i_mutex);
+	n = generic_file_llseek_unlocked(file, offset, origin);
+	mutex_unlock(&file->f_dentry->d_inode->i_mutex);
+	return n;
 }
-EXPORT_SYMBOL(remote_llseek);
+EXPORT_SYMBOL(generic_file_llseek);
 
 loff_t no_llseek(struct file *file, loff_t offset, int origin)
 {
diff --git a/fs/reiserfs/inode.c b/fs/reiserfs/inode.c
index 57917932212..192269698a8 100644
--- a/fs/reiserfs/inode.c
+++ b/fs/reiserfs/inode.c
@@ -45,6 +45,8 @@ void reiserfs_delete_inode(struct inode *inode)
 			goto out;
 		reiserfs_update_inode_transaction(inode);
 
+		reiserfs_discard_prealloc(&th, inode);
+
 		err = reiserfs_delete_object(&th, inode);
 
 		/* Do quota update inside a transaction for journaled quotas. We must do that
diff --git a/fs/reiserfs/super.c b/fs/reiserfs/super.c
index ed424d708e6..1d40f2bd197 100644
--- a/fs/reiserfs/super.c
+++ b/fs/reiserfs/super.c
@@ -2165,8 +2165,10 @@ static ssize_t reiserfs_quota_write(struct super_block *sb, int type,
 		blk++;
 	}
 out:
-	if (len == towrite)
+	if (len == towrite) {
+		mutex_unlock(&inode->i_mutex);
 		return err;
+	}
 	if (inode->i_size < off + len - towrite)
 		i_size_write(inode, off + len - towrite);
 	inode->i_version++;
diff --git a/fs/smbfs/file.c b/fs/smbfs/file.c
index efbe29af3d7..2294783320c 100644
--- a/fs/smbfs/file.c
+++ b/fs/smbfs/file.c
@@ -422,9 +422,18 @@ smb_file_permission(struct inode *inode, int mask, struct nameidata *nd)
 	return error;
 }
 
+static loff_t smb_remote_llseek(struct file *file, loff_t offset, int origin)
+{
+	loff_t ret;
+	lock_kernel();
+	ret = generic_file_llseek_unlocked(file, offset, origin);
+	unlock_kernel();
+	return ret;
+}
+
 const struct file_operations smb_file_operations =
 {
-	.llseek		= remote_llseek,
+	.llseek 	= smb_remote_llseek,
 	.read		= do_sync_read,
 	.aio_read	= smb_file_aio_read,
 	.write		= do_sync_write,
diff --git a/fs/splice.c b/fs/splice.c
index aa5f6f60b30..399442179d8 100644
--- a/fs/splice.c
+++ b/fs/splice.c
@@ -379,13 +379,22 @@ __generic_file_splice_read(struct file *in, loff_t *ppos,
 				lock_page(page);
 
 			/*
-			 * page was truncated, stop here. if this isn't the
-			 * first page, we'll just complete what we already
-			 * added
+			 * Page was truncated, or invalidated by the
+			 * filesystem.  Redo the find/create, but this time the
+			 * page is kept locked, so there's no chance of another
+			 * race with truncate/invalidate.
 			 */
 			if (!page->mapping) {
 				unlock_page(page);
-				break;
+				page = find_or_create_page(mapping, index,
+						mapping_gfp_mask(mapping));
+
+				if (!page) {
+					error = -ENOMEM;
+					break;
+				}
+				page_cache_release(pages[page_nr]);
+				pages[page_nr] = page;
 			}
 			/*
 			 * page was already under io and is now done, great
diff --git a/fs/ubifs/Kconfig b/fs/ubifs/Kconfig
new file mode 100644
index 00000000000..91ceeda7e5b
--- /dev/null
+++ b/fs/ubifs/Kconfig
@@ -0,0 +1,72 @@
+config UBIFS_FS
+	tristate "UBIFS file system support"
+	select CRC16
+	select CRC32
+	select CRYPTO if UBIFS_FS_ADVANCED_COMPR
+	select CRYPTO if UBIFS_FS_LZO
+	select CRYPTO if UBIFS_FS_ZLIB
+	select CRYPTO_LZO if UBIFS_FS_LZO
+	select CRYPTO_DEFLATE if UBIFS_FS_ZLIB
+	depends on MTD_UBI
+	help
+	  UBIFS is a file system for flash devices which works on top of UBI.
+
+config UBIFS_FS_XATTR
+	bool "Extended attributes support"
+	depends on UBIFS_FS
+	help
+	  This option enables support of extended attributes.
+
+config UBIFS_FS_ADVANCED_COMPR
+	bool "Advanced compression options"
+	depends on UBIFS_FS
+	help
+	  This option allows to explicitly choose which compressions, if any,
+	  are enabled in UBIFS. Removing compressors means inbility to read
+	  existing file systems.
+
+	  If unsure, say 'N'.
+
+config UBIFS_FS_LZO
+	bool "LZO compression support" if UBIFS_FS_ADVANCED_COMPR
+	depends on UBIFS_FS
+	default y
+	help
+	   LZO compressor is generally faster then zlib but compresses worse.
+	   Say 'Y' if unsure.
+
+config UBIFS_FS_ZLIB
+	bool "ZLIB compression support" if UBIFS_FS_ADVANCED_COMPR
+	depends on UBIFS_FS
+	default y
+	help
+	  Zlib copresses better then LZO but it is slower. Say 'Y' if unsure.
+
+# Debugging-related stuff
+config UBIFS_FS_DEBUG
+	bool "Enable debugging"
+	depends on UBIFS_FS
+	select DEBUG_FS
+	select KALLSYMS_ALL
+	help
+	  This option enables UBIFS debugging.
+
+config UBIFS_FS_DEBUG_MSG_LVL
+	int "Default message level (0 = no extra messages, 3 = lots)"
+	depends on UBIFS_FS_DEBUG
+	default "0"
+	help
+	  This controls the amount of debugging messages produced by UBIFS.
+	  If reporting bugs, please try to have available a full dump of the
+	  messages at level 1 while the misbehaviour was occurring. Level 2
+	  may become necessary if level 1 messages were not enough to find the
+	  bug. Generally Level 3 should be avoided.
+
+config UBIFS_FS_DEBUG_CHKS
+	bool "Enable extra checks"
+	depends on UBIFS_FS_DEBUG
+	help
+	  If extra checks are enabled UBIFS will check the consistency of its
+	  internal data structures during operation. However, UBIFS performance
+	  is dramatically slower when this option is selected especially if the
+	  file system is large.
diff --git a/fs/ubifs/Makefile b/fs/ubifs/Makefile
new file mode 100644
index 00000000000..80e93c35e49
--- /dev/null
+++ b/fs/ubifs/Makefile
@@ -0,0 +1,9 @@
+obj-$(CONFIG_UBIFS_FS) += ubifs.o
+
+ubifs-y += shrinker.o journal.o file.o dir.o super.o sb.o io.o
+ubifs-y += tnc.o master.o scan.o replay.o log.o commit.o gc.o orphan.o
+ubifs-y += budget.o find.o tnc_commit.o compress.o lpt.o lprops.o
+ubifs-y += recovery.o ioctl.o lpt_commit.o tnc_misc.o
+
+ubifs-$(CONFIG_UBIFS_FS_DEBUG) += debug.o
+ubifs-$(CONFIG_UBIFS_FS_XATTR) += xattr.o
diff --git a/fs/ubifs/budget.c b/fs/ubifs/budget.c
new file mode 100644
index 00000000000..d81fb9ed2b8
--- /dev/null
+++ b/fs/ubifs/budget.c
@@ -0,0 +1,731 @@
+/*
+ * This file is part of UBIFS.
+ *
+ * Copyright (C) 2006-2008 Nokia Corporation.
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 as published by
+ * the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
+ * more details.
+ *
+ * You should have received a copy of the GNU General Public License along with
+ * this program; if not, write to the Free Software Foundation, Inc., 51
+ * Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
+ *
+ * Authors: Adrian Hunter
+ *          Artem Bityutskiy (Битюцкий Артём)
+ */
+
+/*
+ * This file implements the budgeting sub-system which is responsible for UBIFS
+ * space management.
+ *
+ * Factors such as compression, wasted space at the ends of LEBs, space in other
+ * journal heads, the effect of updates on the index, and so on, make it
+ * impossible to accurately predict the amount of space needed. Consequently
+ * approximations are used.
+ */
+
+#include "ubifs.h"
+#include <linux/writeback.h>
+#include <asm/div64.h>
+
+/*
+ * When pessimistic budget calculations say that there is no enough space,
+ * UBIFS starts writing back dirty inodes and pages, doing garbage collection,
+ * or committing. The below constants define maximum number of times UBIFS
+ * repeats the operations.
+ */
+#define MAX_SHRINK_RETRIES 8
+#define MAX_GC_RETRIES     4
+#define MAX_CMT_RETRIES    2
+#define MAX_NOSPC_RETRIES  1
+
+/*
+ * The below constant defines amount of dirty pages which should be written
+ * back at when trying to shrink the liability.
+ */
+#define NR_TO_WRITE 16
+
+/**
+ * struct retries_info - information about re-tries while making free space.
+ * @prev_liability: previous liability
+ * @shrink_cnt: how many times the liability was shrinked
+ * @shrink_retries: count of liability shrink re-tries (increased when
+ *                  liability does not shrink)
+ * @try_gc: GC should be tried first
+ * @gc_retries: how many times GC was run
+ * @cmt_retries: how many times commit has been done
+ * @nospc_retries: how many times GC returned %-ENOSPC
+ *
+ * Since we consider budgeting to be the fast-path, and this structure has to
+ * be allocated on stack and zeroed out, we make it smaller using bit-fields.
+ */
+struct retries_info {
+	long long prev_liability;
+	unsigned int shrink_cnt;
+	unsigned int shrink_retries:5;
+	unsigned int try_gc:1;
+	unsigned int gc_retries:4;
+	unsigned int cmt_retries:3;
+	unsigned int nospc_retries:1;
+};
+
+/**
+ * shrink_liability - write-back some dirty pages/inodes.
+ * @c: UBIFS file-system description object
+ * @nr_to_write: how many dirty pages to write-back
+ *
+ * This function shrinks UBIFS liability by means of writing back some amount
+ * of dirty inodes and their pages. Returns the amount of pages which were
+ * written back. The returned value does not include dirty inodes which were
+ * synchronized.
+ *
+ * Note, this function synchronizes even VFS inodes which are locked
+ * (@i_mutex) by the caller of the budgeting function, because write-back does
+ * not touch @i_mutex.
+ */
+static int shrink_liability(struct ubifs_info *c, int nr_to_write)
+{
+	int nr_written;
+	struct writeback_control wbc = {
+		.sync_mode   = WB_SYNC_NONE,
+		.range_end   = LLONG_MAX,
+		.nr_to_write = nr_to_write,
+	};
+
+	generic_sync_sb_inodes(c->vfs_sb, &wbc);
+	nr_written = nr_to_write - wbc.nr_to_write;
+
+	if (!nr_written) {
+		/*
+		 * Re-try again but wait on pages/inodes which are being
+		 * written-back concurrently (e.g., by pdflush).
+		 */
+		memset(&wbc, 0, sizeof(struct writeback_control));
+		wbc.sync_mode   = WB_SYNC_ALL;
+		wbc.range_end   = LLONG_MAX;
+		wbc.nr_to_write = nr_to_write;
+		generic_sync_sb_inodes(c->vfs_sb, &wbc);
+		nr_written = nr_to_write - wbc.nr_to_write;
+	}
+
+	dbg_budg("%d pages were written back", nr_written);
+	return nr_written;
+}
+
+
+/**
+ * run_gc - run garbage collector.
+ * @c: UBIFS file-system description object
+ *
+ * This function runs garbage collector to make some more free space. Returns
+ * zero if a free LEB has been produced, %-EAGAIN if commit is required, and a
+ * negative error code in case of failure.
+ */
+static int run_gc(struct ubifs_info *c)
+{
+	int err, lnum;
+
+	/* Make some free space by garbage-collecting dirty space */
+	down_read(&c->commit_sem);
+	lnum = ubifs_garbage_collect(c, 1);
+	up_read(&c->commit_sem);
+	if (lnum < 0)
+		return lnum;
+
+	/* GC freed one LEB, return it to lprops */
+	dbg_budg("GC freed LEB %d", lnum);
+	err = ubifs_return_leb(c, lnum);
+	if (err)
+		return err;
+	return 0;
+}
+
+/**
+ * make_free_space - make more free space on the file-system.
+ * @c: UBIFS file-system description object
+ * @ri: information about previous invocations of this function
+ *
+ * This function is called when an operation cannot be budgeted because there
+ * is supposedly no free space. But in most cases there is some free space:
+ *   o budgeting is pessimistic, so it always budgets more then it is actually
+ *     needed, so shrinking the liability is one way to make free space - the
+ *     cached data will take less space then it was budgeted for;
+ *   o GC may turn some dark space into free space (budgeting treats dark space
+ *     as not available);
+ *   o commit may free some LEB, i.e., turn freeable LEBs into free LEBs.
+ *
+ * So this function tries to do the above. Returns %-EAGAIN if some free space
+ * was presumably made and the caller has to re-try budgeting the operation.
+ * Returns %-ENOSPC if it couldn't do more free space, and other negative error
+ * codes on failures.
+ */
+static int make_free_space(struct ubifs_info *c, struct retries_info *ri)
+{
+	int err;
+
+	/*
+	 * If we have some dirty pages and inodes (liability), try to write
+	 * them back unless this was tried too many times without effect
+	 * already.
+	 */
+	if (ri->shrink_retries < MAX_SHRINK_RETRIES && !ri->try_gc) {
+		long long liability;
+
+		spin_lock(&c->space_lock);
+		liability = c->budg_idx_growth + c->budg_data_growth +
+			    c->budg_dd_growth;
+		spin_unlock(&c->space_lock);
+
+		if (ri->prev_liability >= liability) {
+			/* Liability does not shrink, next time try GC then */
+			ri->shrink_retries += 1;
+			if (ri->gc_retries < MAX_GC_RETRIES)
+				ri->try_gc = 1;
+			dbg_budg("liability did not shrink: retries %d of %d",
+				 ri->shrink_retries, MAX_SHRINK_RETRIES);
+		}
+
+		dbg_budg("force write-back (count %d)", ri->shrink_cnt);
+		shrink_liability(c, NR_TO_WRITE + ri->shrink_cnt);
+
+		ri->prev_liability = liability;
+		ri->shrink_cnt += 1;
+		return -EAGAIN;
+	}
+
+	/*
+	 * Try to run garbage collector unless it was already tried too many
+	 * times.
+	 */
+	if (ri->gc_retries < MAX_GC_RETRIES) {
+		ri->gc_retries += 1;
+		dbg_budg("run GC, retries %d of %d",
+			 ri->gc_retries, MAX_GC_RETRIES);
+
+		ri->try_gc = 0;
+		err = run_gc(c);
+		if (!err)
+			return -EAGAIN;
+
+		if (err == -EAGAIN) {
+			dbg_budg("GC asked to commit");
+			err = ubifs_run_commit(c);
+			if (err)
+				return err;
+			return -EAGAIN;
+		}
+
+		if (err != -ENOSPC)
+			return err;
+
+		/*
+		 * GC could not make any progress. If this is the first time,
+		 * then it makes sense to try to commit, because it might make
+		 * some dirty space.
+		 */
+		dbg_budg("GC returned -ENOSPC, retries %d",
+			 ri->nospc_retries);
+		if (ri->nospc_retries >= MAX_NOSPC_RETRIES)
+			return err;
+		ri->nospc_retries += 1;
+	}
+
+	/* Neither GC nor write-back helped, try to commit */
+	if (ri->cmt_retries < MAX_CMT_RETRIES) {
+		ri->cmt_retries += 1;
+		dbg_budg("run commit, retries %d of %d",
+			 ri->cmt_retries, MAX_CMT_RETRIES);
+		err = ubifs_run_commit(c);
+		if (err)
+			return err;
+		return -EAGAIN;
+	}
+	return -ENOSPC;
+}
+
+/**
+ * ubifs_calc_min_idx_lebs - calculate amount of eraseblocks for the index.
+ * @c: UBIFS file-system description object
+ *
+ * This function calculates and returns the number of eraseblocks which should
+ * be kept for index usage.
+ */
+int ubifs_calc_min_idx_lebs(struct ubifs_info *c)
+{
+	int ret;
+	uint64_t idx_size;
+
+	idx_size = c->old_idx_sz + c->budg_idx_growth + c->budg_uncommitted_idx;
+
+	/* And make sure we have twice the index size of space reserved */
+	idx_size <<= 1;
+
+	/*
+	 * We do not maintain 'old_idx_size' as 'old_idx_lebs'/'old_idx_bytes'
+	 * pair, nor similarly the two variables for the new index size, so we
+	 * have to do this costly 64-bit division on fast-path.
+	 */
+	if (do_div(idx_size, c->leb_size - c->max_idx_node_sz))
+		ret = idx_size + 1;
+	else
+		ret = idx_size;
+	/*
+	 * The index head is not available for the in-the-gaps method, so add an
+	 * extra LEB to compensate.
+	 */
+	ret += 1;
+	/*
+	 * At present the index needs at least 2 LEBs: one for the index head
+	 * and one for in-the-gaps method (which currently does not cater for
+	 * the index head and so excludes it from consideration).
+	 */
+	if (ret < 2)
+		ret = 2;
+	return ret;
+}
+
+/**
+ * ubifs_calc_available - calculate available FS space.
+ * @c: UBIFS file-system description object
+ * @min_idx_lebs: minimum number of LEBs reserved for the index
+ *
+ * This function calculates and returns amount of FS space available for use.
+ */
+long long ubifs_calc_available(const struct ubifs_info *c, int min_idx_lebs)
+{
+	int subtract_lebs;
+	long long available;
+
+	/*
+	 * Force the amount available to the total size reported if the used
+	 * space is zero.
+	 */
+	if (c->lst.total_used <= UBIFS_INO_NODE_SZ &&
+	    c->budg_data_growth + c->budg_dd_growth == 0) {
+		/* Do the same calculation as for c->block_cnt */
+		available = c->main_lebs - 2;
+		available *= c->leb_size - c->dark_wm;
+		return available;
+	}
+
+	available = c->main_bytes - c->lst.total_used;
+
+	/*
+	 * Now 'available' contains theoretically available flash space
+	 * assuming there is no index, so we have to subtract the space which
+	 * is reserved for the index.
+	 */
+	subtract_lebs = min_idx_lebs;
+
+	/* Take into account that GC reserves one LEB for its own needs */
+	subtract_lebs += 1;
+
+	/*
+	 * The GC journal head LEB is not really accessible. And since
+	 * different write types go to different heads, we may count only on
+	 * one head's space.
+	 */
+	subtract_lebs += c->jhead_cnt - 1;
+
+	/* We also reserve one LEB for deletions, which bypass budgeting */
+	subtract_lebs += 1;
+
+	available -= (long long)subtract_lebs * c->leb_size;
+
+	/* Subtract the dead space which is not available for use */
+	available -= c->lst.total_dead;
+
+	/*
+	 * Subtract dark space, which might or might not be usable - it depends
+	 * on the data which we have on the media and which will be written. If
+	 * this is a lot of uncompressed or not-compressible data, the dark
+	 * space cannot be used.
+	 */
+	available -= c->lst.total_dark;
+
+	/*
+	 * However, there is more dark space. The index may be bigger than
+	 * @min_idx_lebs. Those extra LEBs are assumed to be available, but
+	 * their dark space is not included in total_dark, so it is subtracted
+	 * here.
+	 */
+	if (c->lst.idx_lebs > min_idx_lebs) {
+		subtract_lebs = c->lst.idx_lebs - min_idx_lebs;
+		available -= subtract_lebs * c->dark_wm;
+	}
+
+	/* The calculations are rough and may end up with a negative number */
+	return available > 0 ? available : 0;
+}
+
+/**
+ * can_use_rp - check whether the user is allowed to use reserved pool.
+ * @c: UBIFS file-system description object
+ *
+ * UBIFS has so-called "reserved pool" which is flash space reserved
+ * for the superuser and for uses whose UID/GID is recorded in UBIFS superblock.
+ * This function checks whether current user is allowed to use reserved pool.
+ * Returns %1  current user is allowed to use reserved pool and %0 otherwise.
+ */
+static int can_use_rp(struct ubifs_info *c)
+{
+	if (current->fsuid == c->rp_uid || capable(CAP_SYS_RESOURCE) ||
+	    (c->rp_gid != 0 && in_group_p(c->rp_gid)))
+		return 1;
+	return 0;
+}
+
+/**
+ * do_budget_space - reserve flash space for index and data growth.
+ * @c: UBIFS file-system description object
+ *
+ * This function makes sure UBIFS has enough free eraseblocks for index growth
+ * and data.
+ *
+ * When budgeting index space, UBIFS reserves twice as more LEBs as the index
+ * would take if it was consolidated and written to the flash. This guarantees
+ * that the "in-the-gaps" commit method always succeeds and UBIFS will always
+ * be able to commit dirty index. So this function basically adds amount of
+ * budgeted index space to the size of the current index, multiplies this by 2,
+ * and makes sure this does not exceed the amount of free eraseblocks.
+ *
+ * Notes about @c->min_idx_lebs and @c->lst.idx_lebs variables:
+ * o @c->lst.idx_lebs is the number of LEBs the index currently uses. It might
+ *    be large, because UBIFS does not do any index consolidation as long as
+ *    there is free space. IOW, the index may take a lot of LEBs, but the LEBs
+ *    will contain a lot of dirt.
+ * o @c->min_idx_lebs is the the index presumably takes. IOW, the index may be
+ *   consolidated to take up to @c->min_idx_lebs LEBs.
+ *
+ * This function returns zero in case of success, and %-ENOSPC in case of
+ * failure.
+ */
+static int do_budget_space(struct ubifs_info *c)
+{
+	long long outstanding, available;
+	int lebs, rsvd_idx_lebs, min_idx_lebs;
+
+	/* First budget index space */
+	min_idx_lebs = ubifs_calc_min_idx_lebs(c);
+
+	/* Now 'min_idx_lebs' contains number of LEBs to reserve */
+	if (min_idx_lebs > c->lst.idx_lebs)
+		rsvd_idx_lebs = min_idx_lebs - c->lst.idx_lebs;
+	else
+		rsvd_idx_lebs = 0;
+
+	/*
+	 * The number of LEBs that are available to be used by the index is:
+	 *
+	 *    @c->lst.empty_lebs + @c->freeable_cnt + @c->idx_gc_cnt -
+	 *    @c->lst.taken_empty_lebs
+	 *
+	 * @empty_lebs are available because they are empty. @freeable_cnt are
+	 * available because they contain only free and dirty space and the
+	 * index allocation always occurs after wbufs are synch'ed.
+	 * @idx_gc_cnt are available because they are index LEBs that have been
+	 * garbage collected (including trivial GC) and are awaiting the commit
+	 * before they can be unmapped - note that the in-the-gaps method will
+	 * grab these if it needs them. @taken_empty_lebs are empty_lebs that
+	 * have already been allocated for some purpose (also includes those
+	 * LEBs on the @idx_gc list).
+	 *
+	 * Note, @taken_empty_lebs may temporarily be higher by one because of
+	 * the way we serialize LEB allocations and budgeting. See a comment in
+	 * 'ubifs_find_free_space()'.
+	 */
+	lebs = c->lst.empty_lebs + c->freeable_cnt + c->idx_gc_cnt -
+	       c->lst.taken_empty_lebs;
+	if (unlikely(rsvd_idx_lebs > lebs)) {
+		dbg_budg("out of indexing space: min_idx_lebs %d (old %d), "
+			 "rsvd_idx_lebs %d", min_idx_lebs, c->min_idx_lebs,
+			 rsvd_idx_lebs);
+		return -ENOSPC;
+	}
+
+	available = ubifs_calc_available(c, min_idx_lebs);
+	outstanding = c->budg_data_growth + c->budg_dd_growth;
+
+	if (unlikely(available < outstanding)) {
+		dbg_budg("out of data space: available %lld, outstanding %lld",
+			 available, outstanding);
+		return -ENOSPC;
+	}
+
+	if (available - outstanding <= c->rp_size && !can_use_rp(c))
+		return -ENOSPC;
+
+	c->min_idx_lebs = min_idx_lebs;
+	return 0;
+}
+
+/**
+ * calc_idx_growth - calculate approximate index growth from budgeting request.
+ * @c: UBIFS file-system description object
+ * @req: budgeting request
+ *
+ * For now we assume each new node adds one znode. But this is rather poor
+ * approximation, though.
+ */
+static int calc_idx_growth(const struct ubifs_info *c,
+			   const struct ubifs_budget_req *req)
+{
+	int znodes;
+
+	znodes = req->new_ino + (req->new_page << UBIFS_BLOCKS_PER_PAGE_SHIFT) +
+		 req->new_dent;
+	return znodes * c->max_idx_node_sz;
+}
+
+/**
+ * calc_data_growth - calculate approximate amount of new data from budgeting
+ * request.
+ * @c: UBIFS file-system description object
+ * @req: budgeting request
+ */
+static int calc_data_growth(const struct ubifs_info *c,
+			    const struct ubifs_budget_req *req)
+{
+	int data_growth;
+
+	data_growth = req->new_ino  ? c->inode_budget : 0;
+	if (req->new_page)
+		data_growth += c->page_budget;
+	if (req->new_dent)
+		data_growth += c->dent_budget;
+	data_growth += req->new_ino_d;
+	return data_growth;
+}
+
+/**
+ * calc_dd_growth - calculate approximate amount of data which makes other data
+ * dirty from budgeting request.
+ * @c: UBIFS file-system description object
+ * @req: budgeting request
+ */
+static int calc_dd_growth(const struct ubifs_info *c,
+			  const struct ubifs_budget_req *req)
+{
+	int dd_growth;
+
+	dd_growth = req->dirtied_page ? c->page_budget : 0;
+
+	if (req->dirtied_ino)
+		dd_growth += c->inode_budget << (req->dirtied_ino - 1);
+	if (req->mod_dent)
+		dd_growth += c->dent_budget;
+	dd_growth += req->dirtied_ino_d;
+	return dd_growth;
+}
+
+/**
+ * ubifs_budget_space - ensure there is enough space to complete an operation.
+ * @c: UBIFS file-system description object
+ * @req: budget request
+ *
+ * This function allocates budget for an operation. It uses pessimistic
+ * approximation of how much flash space the operation needs. The goal of this
+ * function is to make sure UBIFS always has flash space to flush all dirty
+ * pages, dirty inodes, and dirty znodes (liability). This function may force
+ * commit, garbage-collection or write-back. Returns zero in case of success,
+ * %-ENOSPC if there is no free space and other negative error codes in case of
+ * failures.
+ */
+int ubifs_budget_space(struct ubifs_info *c, struct ubifs_budget_req *req)
+{
+	int uninitialized_var(cmt_retries), uninitialized_var(wb_retries);
+	int err, idx_growth, data_growth, dd_growth;
+	struct retries_info ri;
+
+	ubifs_assert(req->dirtied_ino <= 4);
+	ubifs_assert(req->dirtied_ino_d <= UBIFS_MAX_INO_DATA * 4);
+
+	data_growth = calc_data_growth(c, req);
+	dd_growth = calc_dd_growth(c, req);
+	if (!data_growth && !dd_growth)
+		return 0;
+	idx_growth = calc_idx_growth(c, req);
+	memset(&ri, 0, sizeof(struct retries_info));
+
+again:
+	spin_lock(&c->space_lock);
+	ubifs_assert(c->budg_idx_growth >= 0);
+	ubifs_assert(c->budg_data_growth >= 0);
+	ubifs_assert(c->budg_dd_growth >= 0);
+
+	if (unlikely(c->nospace) && (c->nospace_rp || !can_use_rp(c))) {
+		dbg_budg("no space");
+		spin_unlock(&c->space_lock);
+		return -ENOSPC;
+	}
+
+	c->budg_idx_growth += idx_growth;
+	c->budg_data_growth += data_growth;
+	c->budg_dd_growth += dd_growth;
+
+	err = do_budget_space(c);
+	if (likely(!err)) {
+		req->idx_growth = idx_growth;
+		req->data_growth = data_growth;
+		req->dd_growth = dd_growth;
+		spin_unlock(&c->space_lock);
+		return 0;
+	}
+
+	/* Restore the old values */
+	c->budg_idx_growth -= idx_growth;
+	c->budg_data_growth -= data_growth;
+	c->budg_dd_growth -= dd_growth;
+	spin_unlock(&c->space_lock);
+
+	if (req->fast) {
+		dbg_budg("no space for fast budgeting");
+		return err;
+	}
+
+	err = make_free_space(c, &ri);
+	if (err == -EAGAIN) {
+		dbg_budg("try again");
+		cond_resched();
+		goto again;
+	} else if (err == -ENOSPC) {
+		dbg_budg("FS is full, -ENOSPC");
+		c->nospace = 1;
+		if (can_use_rp(c) || c->rp_size == 0)
+			c->nospace_rp = 1;
+		smp_wmb();
+	} else
+		ubifs_err("cannot budget space, error %d", err);
+	return err;
+}
+
+/**
+ * ubifs_release_budget - release budgeted free space.
+ * @c: UBIFS file-system description object
+ * @req: budget request
+ *
+ * This function releases the space budgeted by 'ubifs_budget_space()'. Note,
+ * since the index changes (which were budgeted for in @req->idx_growth) will
+ * only be written to the media on commit, this function moves the index budget
+ * from @c->budg_idx_growth to @c->budg_uncommitted_idx. The latter will be
+ * zeroed by the commit operation.
+ */
+void ubifs_release_budget(struct ubifs_info *c, struct ubifs_budget_req *req)
+{
+	ubifs_assert(req->dirtied_ino <= 4);
+	ubifs_assert(req->dirtied_ino_d <= UBIFS_MAX_INO_DATA * 4);
+	if (!req->recalculate) {
+		ubifs_assert(req->idx_growth >= 0);
+		ubifs_assert(req->data_growth >= 0);
+		ubifs_assert(req->dd_growth >= 0);
+	}
+
+	if (req->recalculate) {
+		req->data_growth = calc_data_growth(c, req);
+		req->dd_growth = calc_dd_growth(c, req);
+		req->idx_growth = calc_idx_growth(c, req);
+	}
+
+	if (!req->data_growth && !req->dd_growth)
+		return;
+
+	c->nospace = c->nospace_rp = 0;
+	smp_wmb();
+
+	spin_lock(&c->space_lock);
+	c->budg_idx_growth -= req->idx_growth;
+	c->budg_uncommitted_idx += req->idx_growth;
+	c->budg_data_growth -= req->data_growth;
+	c->budg_dd_growth -= req->dd_growth;
+	c->min_idx_lebs = ubifs_calc_min_idx_lebs(c);
+
+	ubifs_assert(c->budg_idx_growth >= 0);
+	ubifs_assert(c->budg_data_growth >= 0);
+	ubifs_assert(c->min_idx_lebs < c->main_lebs);
+	spin_unlock(&c->space_lock);
+}
+
+/**
+ * ubifs_convert_page_budget - convert budget of a new page.
+ * @c: UBIFS file-system description object
+ *
+ * This function converts budget which was allocated for a new page of data to
+ * the budget of changing an existing page of data. The latter is smaller then
+ * the former, so this function only does simple re-calculation and does not
+ * involve any write-back.
+ */
+void ubifs_convert_page_budget(struct ubifs_info *c)
+{
+	spin_lock(&c->space_lock);
+	/* Release the index growth reservation */
+	c->budg_idx_growth -= c->max_idx_node_sz << UBIFS_BLOCKS_PER_PAGE_SHIFT;
+	/* Release the data growth reservation */
+	c->budg_data_growth -= c->page_budget;
+	/* Increase the dirty data growth reservation instead */
+	c->budg_dd_growth += c->page_budget;
+	/* And re-calculate the indexing space reservation */
+	c->min_idx_lebs = ubifs_calc_min_idx_lebs(c);
+	spin_unlock(&c->space_lock);
+}
+
+/**
+ * ubifs_release_dirty_inode_budget - release dirty inode budget.
+ * @c: UBIFS file-system description object
+ * @ui: UBIFS inode to release the budget for
+ *
+ * This function releases budget corresponding to a dirty inode. It is usually
+ * called when after the inode has been written to the media and marked as
+ * clean.
+ */
+void ubifs_release_dirty_inode_budget(struct ubifs_info *c,
+				      struct ubifs_inode *ui)
+{
+	struct ubifs_budget_req req = {.dd_growth = c->inode_budget,
+				       .dirtied_ino_d = ui->data_len};
+
+	ubifs_release_budget(c, &req);
+}
+
+/**
+ * ubifs_budg_get_free_space - return amount of free space.
+ * @c: UBIFS file-system description object
+ *
+ * This function returns amount of free space on the file-system.
+ */
+long long ubifs_budg_get_free_space(struct ubifs_info *c)
+{
+	int min_idx_lebs, rsvd_idx_lebs;
+	long long available, outstanding, free;
+
+	/* Do exactly the same calculations as in 'do_budget_space()' */
+	spin_lock(&c->space_lock);
+	min_idx_lebs = ubifs_calc_min_idx_lebs(c);
+
+	if (min_idx_lebs > c->lst.idx_lebs)
+		rsvd_idx_lebs = min_idx_lebs - c->lst.idx_lebs;
+	else
+		rsvd_idx_lebs = 0;
+
+	if (rsvd_idx_lebs > c->lst.empty_lebs + c->freeable_cnt + c->idx_gc_cnt
+				- c->lst.taken_empty_lebs) {
+		spin_unlock(&c->space_lock);
+		return 0;
+	}
+
+	available = ubifs_calc_available(c, min_idx_lebs);
+	outstanding = c->budg_data_growth + c->budg_dd_growth;
+	c->min_idx_lebs = min_idx_lebs;
+	spin_unlock(&c->space_lock);
+
+	if (available > outstanding)
+		free = ubifs_reported_space(c, available - outstanding);
+	else
+		free = 0;
+	return free;
+}
diff --git a/fs/ubifs/commit.c b/fs/ubifs/commit.c
new file mode 100644
index 00000000000..3b516316c9b
--- /dev/null
+++ b/fs/ubifs/commit.c
@@ -0,0 +1,677 @@
+/*
+ * This file is part of UBIFS.
+ *
+ * Copyright (C) 2006-2008 Nokia Corporation.
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 as published by
+ * the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
+ * more details.
+ *
+ * You should have received a copy of the GNU General Public License along with
+ * this program; if not, write to the Free Software Foundation, Inc., 51
+ * Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
+ *
+ * Authors: Adrian Hunter
+ *          Artem Bityutskiy (Битюцкий Артём)
+ */
+
+/*
+ * This file implements functions that manage the running of the commit process.
+ * Each affected module has its own functions to accomplish their part in the
+ * commit and those functions are called here.
+ *
+ * The commit is the process whereby all updates to the index and LEB properties
+ * are written out together and the journal becomes empty. This keeps the
+ * file system consistent - at all times the state can be recreated by reading
+ * the index and LEB properties and then replaying the journal.
+ *
+ * The commit is split into two parts named "commit start" and "commit end".
+ * During commit start, the commit process has exclusive access to the journal
+ * by holding the commit semaphore down for writing. As few I/O operations as
+ * possible are performed during commit start, instead the nodes that are to be
+ * written are merely identified. During commit end, the commit semaphore is no
+ * longer held and the journal is again in operation, allowing users to continue
+ * to use the file system while the bulk of the commit I/O is performed. The
+ * purpose of this two-step approach is to prevent the commit from causing any
+ * latency blips. Note that in any case, the commit does not prevent lookups
+ * (as permitted by the TNC mutex), or access to VFS data structures e.g. page
+ * cache.
+ */
+
+#include <linux/freezer.h>
+#include <linux/kthread.h>
+#include "ubifs.h"
+
+/**
+ * do_commit - commit the journal.
+ * @c: UBIFS file-system description object
+ *
+ * This function implements UBIFS commit. It has to be called with commit lock
+ * locked. Returns zero in case of success and a negative error code in case of
+ * failure.
+ */
+static int do_commit(struct ubifs_info *c)
+{
+	int err, new_ltail_lnum, old_ltail_lnum, i;
+	struct ubifs_zbranch zroot;
+	struct ubifs_lp_stats lst;
+
+	dbg_cmt("start");
+	if (c->ro_media) {
+		err = -EROFS;
+		goto out_up;
+	}
+
+	/* Sync all write buffers (necessary for recovery) */
+	for (i = 0; i < c->jhead_cnt; i++) {
+		err = ubifs_wbuf_sync(&c->jheads[i].wbuf);
+		if (err)
+			goto out_up;
+	}
+
+	err = ubifs_gc_start_commit(c);
+	if (err)
+		goto out_up;
+	err = dbg_check_lprops(c);
+	if (err)
+		goto out_up;
+	err = ubifs_log_start_commit(c, &new_ltail_lnum);
+	if (err)
+		goto out_up;
+	err = ubifs_tnc_start_commit(c, &zroot);
+	if (err)
+		goto out_up;
+	err = ubifs_lpt_start_commit(c);
+	if (err)
+		goto out_up;
+	err = ubifs_orphan_start_commit(c);
+	if (err)
+		goto out_up;
+
+	ubifs_get_lp_stats(c, &lst);
+
+	up_write(&c->commit_sem);
+
+	err = ubifs_tnc_end_commit(c);
+	if (err)
+		goto out;
+	err = ubifs_lpt_end_commit(c);
+	if (err)
+		goto out;
+	err = ubifs_orphan_end_commit(c);
+	if (err)
+		goto out;
+	old_ltail_lnum = c->ltail_lnum;
+	err = ubifs_log_end_commit(c, new_ltail_lnum);
+	if (err)
+		goto out;
+	err = dbg_check_old_index(c, &zroot);
+	if (err)
+		goto out;
+
+	mutex_lock(&c->mst_mutex);
+	c->mst_node->cmt_no      = cpu_to_le64(++c->cmt_no);
+	c->mst_node->log_lnum    = cpu_to_le32(new_ltail_lnum);
+	c->mst_node->root_lnum   = cpu_to_le32(zroot.lnum);
+	c->mst_node->root_offs   = cpu_to_le32(zroot.offs);
+	c->mst_node->root_len    = cpu_to_le32(zroot.len);
+	c->mst_node->ihead_lnum  = cpu_to_le32(c->ihead_lnum);
+	c->mst_node->ihead_offs  = cpu_to_le32(c->ihead_offs);
+	c->mst_node->index_size  = cpu_to_le64(c->old_idx_sz);
+	c->mst_node->lpt_lnum    = cpu_to_le32(c->lpt_lnum);
+	c->mst_node->lpt_offs    = cpu_to_le32(c->lpt_offs);
+	c->mst_node->nhead_lnum  = cpu_to_le32(c->nhead_lnum);
+	c->mst_node->nhead_offs  = cpu_to_le32(c->nhead_offs);
+	c->mst_node->ltab_lnum   = cpu_to_le32(c->ltab_lnum);
+	c->mst_node->ltab_offs   = cpu_to_le32(c->ltab_offs);
+	c->mst_node->lsave_lnum  = cpu_to_le32(c->lsave_lnum);
+	c->mst_node->lsave_offs  = cpu_to_le32(c->lsave_offs);
+	c->mst_node->lscan_lnum  = cpu_to_le32(c->lscan_lnum);
+	c->mst_node->empty_lebs  = cpu_to_le32(lst.empty_lebs);
+	c->mst_node->idx_lebs    = cpu_to_le32(lst.idx_lebs);
+	c->mst_node->total_free  = cpu_to_le64(lst.total_free);
+	c->mst_node->total_dirty = cpu_to_le64(lst.total_dirty);
+	c->mst_node->total_used  = cpu_to_le64(lst.total_used);
+	c->mst_node->total_dead  = cpu_to_le64(lst.total_dead);
+	c->mst_node->total_dark  = cpu_to_le64(lst.total_dark);
+	if (c->no_orphs)
+		c->mst_node->flags |= cpu_to_le32(UBIFS_MST_NO_ORPHS);
+	else
+		c->mst_node->flags &= ~cpu_to_le32(UBIFS_MST_NO_ORPHS);
+	err = ubifs_write_master(c);
+	mutex_unlock(&c->mst_mutex);
+	if (err)
+		goto out;
+
+	err = ubifs_log_post_commit(c, old_ltail_lnum);
+	if (err)
+		goto out;
+	err = ubifs_gc_end_commit(c);
+	if (err)
+		goto out;
+	err = ubifs_lpt_post_commit(c);
+	if (err)
+		goto out;
+
+	spin_lock(&c->cs_lock);
+	c->cmt_state = COMMIT_RESTING;
+	wake_up(&c->cmt_wq);
+	dbg_cmt("commit end");
+	spin_unlock(&c->cs_lock);
+
+	return 0;
+
+out_up:
+	up_write(&c->commit_sem);
+out:
+	ubifs_err("commit failed, error %d", err);
+	spin_lock(&c->cs_lock);
+	c->cmt_state = COMMIT_BROKEN;
+	wake_up(&c->cmt_wq);
+	spin_unlock(&c->cs_lock);
+	ubifs_ro_mode(c, err);
+	return err;
+}
+
+/**
+ * run_bg_commit - run background commit if it is needed.
+ * @c: UBIFS file-system description object
+ *
+ * This function runs background commit if it is needed. Returns zero in case
+ * of success and a negative error code in case of failure.
+ */
+static int run_bg_commit(struct ubifs_info *c)
+{
+	spin_lock(&c->cs_lock);
+	/*
+	 * Run background commit only if background commit was requested or if
+	 * commit is required.
+	 */
+	if (c->cmt_state != COMMIT_BACKGROUND &&
+	    c->cmt_state != COMMIT_REQUIRED)
+		goto out;
+	spin_unlock(&c->cs_lock);
+
+	down_write(&c->commit_sem);
+	spin_lock(&c->cs_lock);
+	if (c->cmt_state == COMMIT_REQUIRED)
+		c->cmt_state = COMMIT_RUNNING_REQUIRED;
+	else if (c->cmt_state == COMMIT_BACKGROUND)
+		c->cmt_state = COMMIT_RUNNING_BACKGROUND;
+	else
+		goto out_cmt_unlock;
+	spin_unlock(&c->cs_lock);
+
+	return do_commit(c);
+
+out_cmt_unlock:
+	up_write(&c->commit_sem);
+out:
+	spin_unlock(&c->cs_lock);
+	return 0;
+}
+
+/**
+ * ubifs_bg_thread - UBIFS background thread function.
+ * @info: points to the file-system description object
+ *
+ * This function implements various file-system background activities:
+ * o when a write-buffer timer expires it synchronizes the appropriate
+ *   write-buffer;
+ * o when the journal is about to be full, it starts in-advance commit.
+ *
+ * Note, other stuff like background garbage collection may be added here in
+ * future.
+ */
+int ubifs_bg_thread(void *info)
+{
+	int err;
+	struct ubifs_info *c = info;
+
+	ubifs_msg("background thread \"%s\" started, PID %d",
+		  c->bgt_name, current->pid);
+	set_freezable();
+
+	while (1) {
+		if (kthread_should_stop())
+			break;
+
+		if (try_to_freeze())
+			continue;
+
+		set_current_state(TASK_INTERRUPTIBLE);
+		/* Check if there is something to do */
+		if (!c->need_bgt) {
+			/*
+			 * Nothing prevents us from going sleep now and
+			 * be never woken up and block the task which
+			 * could wait in 'kthread_stop()' forever.
+			 */
+			if (kthread_should_stop())
+				break;
+			schedule();
+			continue;
+		} else
+			__set_current_state(TASK_RUNNING);
+
+		c->need_bgt = 0;
+		err = ubifs_bg_wbufs_sync(c);
+		if (err)
+			ubifs_ro_mode(c, err);
+
+		run_bg_commit(c);
+		cond_resched();
+	}
+
+	dbg_msg("background thread \"%s\" stops", c->bgt_name);
+	return 0;
+}
+
+/**
+ * ubifs_commit_required - set commit state to "required".
+ * @c: UBIFS file-system description object
+ *
+ * This function is called if a commit is required but cannot be done from the
+ * calling function, so it is just flagged instead.
+ */
+void ubifs_commit_required(struct ubifs_info *c)
+{
+	spin_lock(&c->cs_lock);
+	switch (c->cmt_state) {
+	case COMMIT_RESTING:
+	case COMMIT_BACKGROUND:
+		dbg_cmt("old: %s, new: %s", dbg_cstate(c->cmt_state),
+			dbg_cstate(COMMIT_REQUIRED));
+		c->cmt_state = COMMIT_REQUIRED;
+		break;
+	case COMMIT_RUNNING_BACKGROUND:
+		dbg_cmt("old: %s, new: %s", dbg_cstate(c->cmt_state),
+			dbg_cstate(COMMIT_RUNNING_REQUIRED));
+		c->cmt_state = COMMIT_RUNNING_REQUIRED;
+		break;
+	case COMMIT_REQUIRED:
+	case COMMIT_RUNNING_REQUIRED:
+	case COMMIT_BROKEN:
+		break;
+	}
+	spin_unlock(&c->cs_lock);
+}
+
+/**
+ * ubifs_request_bg_commit - notify the background thread to do a commit.
+ * @c: UBIFS file-system description object
+ *
+ * This function is called if the journal is full enough to make a commit
+ * worthwhile, so background thread is kicked to start it.
+ */
+void ubifs_request_bg_commit(struct ubifs_info *c)
+{
+	spin_lock(&c->cs_lock);
+	if (c->cmt_state == COMMIT_RESTING) {
+		dbg_cmt("old: %s, new: %s", dbg_cstate(c->cmt_state),
+			dbg_cstate(COMMIT_BACKGROUND));
+		c->cmt_state = COMMIT_BACKGROUND;
+		spin_unlock(&c->cs_lock);
+		ubifs_wake_up_bgt(c);
+	} else
+		spin_unlock(&c->cs_lock);
+}
+
+/**
+ * wait_for_commit - wait for commit.
+ * @c: UBIFS file-system description object
+ *
+ * This function sleeps until the commit operation is no longer running.
+ */
+static int wait_for_commit(struct ubifs_info *c)
+{
+	dbg_cmt("pid %d goes sleep", current->pid);
+
+	/*
+	 * The following sleeps if the condition is false, and will be woken
+	 * when the commit ends. It is possible, although very unlikely, that we
+	 * will wake up and see the subsequent commit running, rather than the
+	 * one we were waiting for, and go back to sleep.  However, we will be
+	 * woken again, so there is no danger of sleeping forever.
+	 */
+	wait_event(c->cmt_wq, c->cmt_state != COMMIT_RUNNING_BACKGROUND &&
+			      c->cmt_state != COMMIT_RUNNING_REQUIRED);
+	dbg_cmt("commit finished, pid %d woke up", current->pid);
+	return 0;
+}
+
+/**
+ * ubifs_run_commit - run or wait for commit.
+ * @c: UBIFS file-system description object
+ *
+ * This function runs commit and returns zero in case of success and a negative
+ * error code in case of failure.
+ */
+int ubifs_run_commit(struct ubifs_info *c)
+{
+	int err = 0;
+
+	spin_lock(&c->cs_lock);
+	if (c->cmt_state == COMMIT_BROKEN) {
+		err = -EINVAL;
+		goto out;
+	}
+
+	if (c->cmt_state == COMMIT_RUNNING_BACKGROUND)
+		/*
+		 * We set the commit state to 'running required' to indicate
+		 * that we want it to complete as quickly as possible.
+		 */
+		c->cmt_state = COMMIT_RUNNING_REQUIRED;
+
+	if (c->cmt_state == COMMIT_RUNNING_REQUIRED) {
+		spin_unlock(&c->cs_lock);
+		return wait_for_commit(c);
+	}
+	spin_unlock(&c->cs_lock);
+
+	/* Ok, the commit is indeed needed */
+
+	down_write(&c->commit_sem);
+	spin_lock(&c->cs_lock);
+	/*
+	 * Since we unlocked 'c->cs_lock', the state may have changed, so
+	 * re-check it.
+	 */
+	if (c->cmt_state == COMMIT_BROKEN) {
+		err = -EINVAL;
+		goto out_cmt_unlock;
+	}
+
+	if (c->cmt_state == COMMIT_RUNNING_BACKGROUND)
+		c->cmt_state = COMMIT_RUNNING_REQUIRED;
+
+	if (c->cmt_state == COMMIT_RUNNING_REQUIRED) {
+		up_write(&c->commit_sem);
+		spin_unlock(&c->cs_lock);
+		return wait_for_commit(c);
+	}
+	c->cmt_state = COMMIT_RUNNING_REQUIRED;
+	spin_unlock(&c->cs_lock);
+
+	err = do_commit(c);
+	return err;
+
+out_cmt_unlock:
+	up_write(&c->commit_sem);
+out:
+	spin_unlock(&c->cs_lock);
+	return err;
+}
+
+/**
+ * ubifs_gc_should_commit - determine if it is time for GC to run commit.
+ * @c: UBIFS file-system description object
+ *
+ * This function is called by garbage collection to determine if commit should
+ * be run. If commit state is @COMMIT_BACKGROUND, which means that the journal
+ * is full enough to start commit, this function returns true. It is not
+ * absolutely necessary to commit yet, but it feels like this should be better
+ * then to keep doing GC. This function returns %1 if GC has to initiate commit
+ * and %0 if not.
+ */
+int ubifs_gc_should_commit(struct ubifs_info *c)
+{
+	int ret = 0;
+
+	spin_lock(&c->cs_lock);
+	if (c->cmt_state == COMMIT_BACKGROUND) {
+		dbg_cmt("commit required now");
+		c->cmt_state = COMMIT_REQUIRED;
+	} else
+		dbg_cmt("commit not requested");
+	if (c->cmt_state == COMMIT_REQUIRED)
+		ret = 1;
+	spin_unlock(&c->cs_lock);
+	return ret;
+}
+
+#ifdef CONFIG_UBIFS_FS_DEBUG
+
+/**
+ * struct idx_node - hold index nodes during index tree traversal.
+ * @list: list
+ * @iip: index in parent (slot number of this indexing node in the parent
+ *       indexing node)
+ * @upper_key: all keys in this indexing node have to be less or equivalent to
+ *             this key
+ * @idx: index node (8-byte aligned because all node structures must be 8-byte
+ *       aligned)
+ */
+struct idx_node {
+	struct list_head list;
+	int iip;
+	union ubifs_key upper_key;
+	struct ubifs_idx_node idx __attribute__((aligned(8)));
+};
+
+/**
+ * dbg_old_index_check_init - get information for the next old index check.
+ * @c: UBIFS file-system description object
+ * @zroot: root of the index
+ *
+ * This function records information about the index that will be needed for the
+ * next old index check i.e. 'dbg_check_old_index()'.
+ *
+ * This function returns %0 on success and a negative error code on failure.
+ */
+int dbg_old_index_check_init(struct ubifs_info *c, struct ubifs_zbranch *zroot)
+{
+	struct ubifs_idx_node *idx;
+	int lnum, offs, len, err = 0;
+
+	c->old_zroot = *zroot;
+
+	lnum = c->old_zroot.lnum;
+	offs = c->old_zroot.offs;
+	len = c->old_zroot.len;
+
+	idx = kmalloc(c->max_idx_node_sz, GFP_NOFS);
+	if (!idx)
+		return -ENOMEM;
+
+	err = ubifs_read_node(c, idx, UBIFS_IDX_NODE, len, lnum, offs);
+	if (err)
+		goto out;
+
+	c->old_zroot_level = le16_to_cpu(idx->level);
+	c->old_zroot_sqnum = le64_to_cpu(idx->ch.sqnum);
+out:
+	kfree(idx);
+	return err;
+}
+
+/**
+ * dbg_check_old_index - check the old copy of the index.
+ * @c: UBIFS file-system description object
+ * @zroot: root of the new index
+ *
+ * In order to be able to recover from an unclean unmount, a complete copy of
+ * the index must exist on flash. This is the "old" index. The commit process
+ * must write the "new" index to flash without overwriting or destroying any
+ * part of the old index. This function is run at commit end in order to check
+ * that the old index does indeed exist completely intact.
+ *
+ * This function returns %0 on success and a negative error code on failure.
+ */
+int dbg_check_old_index(struct ubifs_info *c, struct ubifs_zbranch *zroot)
+{
+	int lnum, offs, len, err = 0, uninitialized_var(last_level), child_cnt;
+	int first = 1, iip;
+	union ubifs_key lower_key, upper_key, l_key, u_key;
+	unsigned long long uninitialized_var(last_sqnum);
+	struct ubifs_idx_node *idx;
+	struct list_head list;
+	struct idx_node *i;
+	size_t sz;
+
+	if (!(ubifs_chk_flags & UBIFS_CHK_OLD_IDX))
+		goto out;
+
+	INIT_LIST_HEAD(&list);
+
+	sz = sizeof(struct idx_node) + ubifs_idx_node_sz(c, c->fanout) -
+	     UBIFS_IDX_NODE_SZ;
+
+	/* Start at the old zroot */
+	lnum = c->old_zroot.lnum;
+	offs = c->old_zroot.offs;
+	len = c->old_zroot.len;
+	iip = 0;
+
+	/*
+	 * Traverse the index tree preorder depth-first i.e. do a node and then
+	 * its subtrees from left to right.
+	 */
+	while (1) {
+		struct ubifs_branch *br;
+
+		/* Get the next index node */
+		i = kmalloc(sz, GFP_NOFS);
+		if (!i) {
+			err = -ENOMEM;
+			goto out_free;
+		}
+		i->iip = iip;
+		/* Keep the index nodes on our path in a linked list */
+		list_add_tail(&i->list, &list);
+		/* Read the index node */
+		idx = &i->idx;
+		err = ubifs_read_node(c, idx, UBIFS_IDX_NODE, len, lnum, offs);
+		if (err)
+			goto out_free;
+		/* Validate index node */
+		child_cnt = le16_to_cpu(idx->child_cnt);
+		if (child_cnt < 1 || child_cnt > c->fanout) {
+			err = 1;
+			goto out_dump;
+		}
+		if (first) {
+			first = 0;
+			/* Check root level and sqnum */
+			if (le16_to_cpu(idx->level) != c->old_zroot_level) {
+				err = 2;
+				goto out_dump;
+			}
+			if (le64_to_cpu(idx->ch.sqnum) != c->old_zroot_sqnum) {
+				err = 3;
+				goto out_dump;
+			}
+			/* Set last values as though root had a parent */
+			last_level = le16_to_cpu(idx->level) + 1;
+			last_sqnum = le64_to_cpu(idx->ch.sqnum) + 1;
+			key_read(c, ubifs_idx_key(c, idx), &lower_key);
+			highest_ino_key(c, &upper_key, INUM_WATERMARK);
+		}
+		key_copy(c, &upper_key, &i->upper_key);
+		if (le16_to_cpu(idx->level) != last_level - 1) {
+			err = 3;
+			goto out_dump;
+		}
+		/*
+		 * The index is always written bottom up hence a child's sqnum
+		 * is always less than the parents.
+		 */
+		if (le64_to_cpu(idx->ch.sqnum) >= last_sqnum) {
+			err = 4;
+			goto out_dump;
+		}
+		/* Check key range */
+		key_read(c, ubifs_idx_key(c, idx), &l_key);
+		br = ubifs_idx_branch(c, idx, child_cnt - 1);
+		key_read(c, &br->key, &u_key);
+		if (keys_cmp(c, &lower_key, &l_key) > 0) {
+			err = 5;
+			goto out_dump;
+		}
+		if (keys_cmp(c, &upper_key, &u_key) < 0) {
+			err = 6;
+			goto out_dump;
+		}
+		if (keys_cmp(c, &upper_key, &u_key) == 0)
+			if (!is_hash_key(c, &u_key)) {
+				err = 7;
+				goto out_dump;
+			}
+		/* Go to next index node */
+		if (le16_to_cpu(idx->level) == 0) {
+			/* At the bottom, so go up until can go right */
+			while (1) {
+				/* Drop the bottom of the list */
+				list_del(&i->list);
+				kfree(i);
+				/* No more list means we are done */
+				if (list_empty(&list))
+					goto out;
+				/* Look at the new bottom */
+				i = list_entry(list.prev, struct idx_node,
+					       list);
+				idx = &i->idx;
+				/* Can we go right */
+				if (iip + 1 < le16_to_cpu(idx->child_cnt)) {
+					iip = iip + 1;
+					break;
+				} else
+					/* Nope, so go up again */
+					iip = i->iip;
+			}
+		} else
+			/* Go down left */
+			iip = 0;
+		/*
+		 * We have the parent in 'idx' and now we set up for reading the
+		 * child pointed to by slot 'iip'.
+		 */
+		last_level = le16_to_cpu(idx->level);
+		last_sqnum = le64_to_cpu(idx->ch.sqnum);
+		br = ubifs_idx_branch(c, idx, iip);
+		lnum = le32_to_cpu(br->lnum);
+		offs = le32_to_cpu(br->offs);
+		len = le32_to_cpu(br->len);
+		key_read(c, &br->key, &lower_key);
+		if (iip + 1 < le16_to_cpu(idx->child_cnt)) {
+			br = ubifs_idx_branch(c, idx, iip + 1);
+			key_read(c, &br->key, &upper_key);
+		} else
+			key_copy(c, &i->upper_key, &upper_key);
+	}
+out:
+	err = dbg_old_index_check_init(c, zroot);
+	if (err)
+		goto out_free;
+
+	return 0;
+
+out_dump:
+	dbg_err("dumping index node (iip=%d)", i->iip);
+	dbg_dump_node(c, idx);
+	list_del(&i->list);
+	kfree(i);
+	if (!list_empty(&list)) {
+		i = list_entry(list.prev, struct idx_node, list);
+		dbg_err("dumping parent index node");
+		dbg_dump_node(c, &i->idx);
+	}
+out_free:
+	while (!list_empty(&list)) {
+		i = list_entry(list.next, struct idx_node, list);
+		list_del(&i->list);
+		kfree(i);
+	}
+	ubifs_err("failed, error %d", err);
+	if (err > 0)
+		err = -EINVAL;
+	return err;
+}
+
+#endif /* CONFIG_UBIFS_FS_DEBUG */
diff --git a/fs/ubifs/compress.c b/fs/ubifs/compress.c
new file mode 100644
index 00000000000..5bb51dac3c1
--- /dev/null
+++ b/fs/ubifs/compress.c
@@ -0,0 +1,253 @@
+/*
+ * This file is part of UBIFS.
+ *
+ * Copyright (C) 2006-2008 Nokia Corporation.
+ * Copyright (C) 2006, 2007 University of Szeged, Hungary
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 as published by
+ * the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
+ * more details.
+ *
+ * You should have received a copy of the GNU General Public License along with
+ * this program; if not, write to the Free Software Foundation, Inc., 51
+ * Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
+ *
+ * Authors: Adrian Hunter
+ *          Artem Bityutskiy (Битюцкий Артём)
+ *          Zoltan Sogor
+ */
+
+/*
+ * This file provides a single place to access to compression and
+ * decompression.
+ */
+
+#include <linux/crypto.h>
+#include "ubifs.h"
+
+/* Fake description object for the "none" compressor */
+static struct ubifs_compressor none_compr = {
+	.compr_type = UBIFS_COMPR_NONE,
+	.name = "no compression",
+	.capi_name = "",
+};
+
+#ifdef CONFIG_UBIFS_FS_LZO
+static DEFINE_MUTEX(lzo_mutex);
+
+static struct ubifs_compressor lzo_compr = {
+	.compr_type = UBIFS_COMPR_LZO,
+	.comp_mutex = &lzo_mutex,
+	.name = "LZO",
+	.capi_name = "lzo",
+};
+#else
+static struct ubifs_compressor lzo_compr = {
+	.compr_type = UBIFS_COMPR_LZO,
+	.name = "LZO",
+};
+#endif
+
+#ifdef CONFIG_UBIFS_FS_ZLIB
+static DEFINE_MUTEX(deflate_mutex);
+static DEFINE_MUTEX(inflate_mutex);
+
+static struct ubifs_compressor zlib_compr = {
+	.compr_type = UBIFS_COMPR_ZLIB,
+	.comp_mutex = &deflate_mutex,
+	.decomp_mutex = &inflate_mutex,
+	.name = "zlib",
+	.capi_name = "deflate",
+};
+#else
+static struct ubifs_compressor zlib_compr = {
+	.compr_type = UBIFS_COMPR_ZLIB,
+	.name = "zlib",
+};
+#endif
+
+/* All UBIFS compressors */
+struct ubifs_compressor *ubifs_compressors[UBIFS_COMPR_TYPES_CNT];
+
+/**
+ * ubifs_compress - compress data.
+ * @in_buf: data to compress
+ * @in_len: length of the data to compress
+ * @out_buf: output buffer where compressed data should be stored
+ * @out_len: output buffer length is returned here
+ * @compr_type: type of compression to use on enter, actually used compression
+ *              type on exit
+ *
+ * This function compresses input buffer @in_buf of length @in_len and stores
+ * the result in the output buffer @out_buf and the resulting length in
+ * @out_len. If the input buffer does not compress, it is just copied to the
+ * @out_buf. The same happens if @compr_type is %UBIFS_COMPR_NONE or if
+ * compression error occurred.
+ *
+ * Note, if the input buffer was not compressed, it is copied to the output
+ * buffer and %UBIFS_COMPR_NONE is returned in @compr_type.
+ *
+ * This functions returns %0 on success or a negative error code on failure.
+ */
+void ubifs_compress(const void *in_buf, int in_len, void *out_buf, int *out_len,
+		    int *compr_type)
+{
+	int err;
+	struct ubifs_compressor *compr = ubifs_compressors[*compr_type];
+
+	if (*compr_type == UBIFS_COMPR_NONE)
+		goto no_compr;
+
+	/* If the input data is small, do not even try to compress it */
+	if (in_len < UBIFS_MIN_COMPR_LEN)
+		goto no_compr;
+
+	if (compr->comp_mutex)
+		mutex_lock(compr->comp_mutex);
+	err = crypto_comp_compress(compr->cc, in_buf, in_len, out_buf,
+				   out_len);
+	if (compr->comp_mutex)
+		mutex_unlock(compr->comp_mutex);
+	if (unlikely(err)) {
+		ubifs_warn("cannot compress %d bytes, compressor %s, "
+			   "error %d, leave data uncompressed",
+			   in_len, compr->name, err);
+		 goto no_compr;
+	}
+
+	/*
+	 * Presently, we just require that compression results in less data,
+	 * rather than any defined minimum compression ratio or amount.
+	 */
+	if (ALIGN(*out_len, 8) >= ALIGN(in_len, 8))
+		goto no_compr;
+
+	return;
+
+no_compr:
+	memcpy(out_buf, in_buf, in_len);
+	*out_len = in_len;
+	*compr_type = UBIFS_COMPR_NONE;
+}
+
+/**
+ * ubifs_decompress - decompress data.
+ * @in_buf: data to decompress
+ * @in_len: length of the data to decompress
+ * @out_buf: output buffer where decompressed data should
+ * @out_len: output length is returned here
+ * @compr_type: type of compression
+ *
+ * This function decompresses data from buffer @in_buf into buffer @out_buf.
+ * The length of the uncompressed data is returned in @out_len. This functions
+ * returns %0 on success or a negative error code on failure.
+ */
+int ubifs_decompress(const void *in_buf, int in_len, void *out_buf,
+		     int *out_len, int compr_type)
+{
+	int err;
+	struct ubifs_compressor *compr;
+
+	if (unlikely(compr_type < 0 || compr_type >= UBIFS_COMPR_TYPES_CNT)) {
+		ubifs_err("invalid compression type %d", compr_type);
+		return -EINVAL;
+	}
+
+	compr = ubifs_compressors[compr_type];
+
+	if (unlikely(!compr->capi_name)) {
+		ubifs_err("%s compression is not compiled in", compr->name);
+		return -EINVAL;
+	}
+
+	if (compr_type == UBIFS_COMPR_NONE) {
+		memcpy(out_buf, in_buf, in_len);
+		*out_len = in_len;
+		return 0;
+	}
+
+	if (compr->decomp_mutex)
+		mutex_lock(compr->decomp_mutex);
+	err = crypto_comp_decompress(compr->cc, in_buf, in_len, out_buf,
+				     out_len);
+	if (compr->decomp_mutex)
+		mutex_unlock(compr->decomp_mutex);
+	if (err)
+		ubifs_err("cannot decompress %d bytes, compressor %s, "
+			  "error %d", in_len, compr->name, err);
+
+	return err;
+}
+
+/**
+ * compr_init - initialize a compressor.
+ * @compr: compressor description object
+ *
+ * This function initializes the requested compressor and returns zero in case
+ * of success or a negative error code in case of failure.
+ */
+static int __init compr_init(struct ubifs_compressor *compr)
+{
+	if (compr->capi_name) {
+		compr->cc = crypto_alloc_comp(compr->capi_name, 0, 0);
+		if (IS_ERR(compr->cc)) {
+			ubifs_err("cannot initialize compressor %s, error %ld",
+				  compr->name, PTR_ERR(compr->cc));
+			return PTR_ERR(compr->cc);
+		}
+	}
+
+	ubifs_compressors[compr->compr_type] = compr;
+	return 0;
+}
+
+/**
+ * compr_exit - de-initialize a compressor.
+ * @compr: compressor description object
+ */
+static void compr_exit(struct ubifs_compressor *compr)
+{
+	if (compr->capi_name)
+		crypto_free_comp(compr->cc);
+	return;
+}
+
+/**
+ * ubifs_compressors_init - initialize UBIFS compressors.
+ *
+ * This function initializes the compressor which were compiled in. Returns
+ * zero in case of success and a negative error code in case of failure.
+ */
+int __init ubifs_compressors_init(void)
+{
+	int err;
+
+	err = compr_init(&lzo_compr);
+	if (err)
+		return err;
+
+	err = compr_init(&zlib_compr);
+	if (err)
+		goto out_lzo;
+
+	ubifs_compressors[UBIFS_COMPR_NONE] = &none_compr;
+	return 0;
+
+out_lzo:
+	compr_exit(&lzo_compr);
+	return err;
+}
+
+/**
+ * ubifs_compressors_exit - de-initialize UBIFS compressors.
+ */
+void __exit ubifs_compressors_exit(void)
+{
+	compr_exit(&lzo_compr);
+	compr_exit(&zlib_compr);
+}
diff --git a/fs/ubifs/debug.c b/fs/ubifs/debug.c
new file mode 100644
index 00000000000..4e3aaeba4ec
--- /dev/null
+++ b/fs/ubifs/debug.c
@@ -0,0 +1,2289 @@
+/*
+ * This file is part of UBIFS.
+ *
+ * Copyright (C) 2006-2008 Nokia Corporation
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 as published by
+ * the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
+ * more details.
+ *
+ * You should have received a copy of the GNU General Public License along with
+ * this program; if not, write to the Free Software Foundation, Inc., 51
+ * Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
+ *
+ * Authors: Artem Bityutskiy (Битюцкий Артём)
+ *          Adrian Hunter
+ */
+
+/*
+ * This file implements most of the debugging stuff which is compiled in only
+ * when it is enabled. But some debugging check functions are implemented in
+ * corresponding subsystem, just because they are closely related and utilize
+ * various local functions of those subsystems.
+ */
+
+#define UBIFS_DBG_PRESERVE_UBI
+
+#include "ubifs.h"
+#include <linux/module.h>
+#include <linux/moduleparam.h>
+
+#ifdef CONFIG_UBIFS_FS_DEBUG
+
+DEFINE_SPINLOCK(dbg_lock);
+
+static char dbg_key_buf0[128];
+static char dbg_key_buf1[128];
+
+unsigned int ubifs_msg_flags = UBIFS_MSG_FLAGS_DEFAULT;
+unsigned int ubifs_chk_flags = UBIFS_CHK_FLAGS_DEFAULT;
+unsigned int ubifs_tst_flags;
+
+module_param_named(debug_msgs, ubifs_msg_flags, uint, S_IRUGO | S_IWUSR);
+module_param_named(debug_chks, ubifs_chk_flags, uint, S_IRUGO | S_IWUSR);
+module_param_named(debug_tsts, ubifs_tst_flags, uint, S_IRUGO | S_IWUSR);
+
+MODULE_PARM_DESC(debug_msgs, "Debug message type flags");
+MODULE_PARM_DESC(debug_chks, "Debug check flags");
+MODULE_PARM_DESC(debug_tsts, "Debug special test flags");
+
+static const char *get_key_fmt(int fmt)
+{
+	switch (fmt) {
+	case UBIFS_SIMPLE_KEY_FMT:
+		return "simple";
+	default:
+		return "unknown/invalid format";
+	}
+}
+
+static const char *get_key_hash(int hash)
+{
+	switch (hash) {
+	case UBIFS_KEY_HASH_R5:
+		return "R5";
+	case UBIFS_KEY_HASH_TEST:
+		return "test";
+	default:
+		return "unknown/invalid name hash";
+	}
+}
+
+static const char *get_key_type(int type)
+{
+	switch (type) {
+	case UBIFS_INO_KEY:
+		return "inode";
+	case UBIFS_DENT_KEY:
+		return "direntry";
+	case UBIFS_XENT_KEY:
+		return "xentry";
+	case UBIFS_DATA_KEY:
+		return "data";
+	case UBIFS_TRUN_KEY:
+		return "truncate";
+	default:
+		return "unknown/invalid key";
+	}
+}
+
+static void sprintf_key(const struct ubifs_info *c, const union ubifs_key *key,
+			char *buffer)
+{
+	char *p = buffer;
+	int type = key_type(c, key);
+
+	if (c->key_fmt == UBIFS_SIMPLE_KEY_FMT) {
+		switch (type) {
+		case UBIFS_INO_KEY:
+			sprintf(p, "(%lu, %s)", key_inum(c, key),
+			       get_key_type(type));
+			break;
+		case UBIFS_DENT_KEY:
+		case UBIFS_XENT_KEY:
+			sprintf(p, "(%lu, %s, %#08x)", key_inum(c, key),
+				get_key_type(type), key_hash(c, key));
+			break;
+		case UBIFS_DATA_KEY:
+			sprintf(p, "(%lu, %s, %u)", key_inum(c, key),
+				get_key_type(type), key_block(c, key));
+			break;
+		case UBIFS_TRUN_KEY:
+			sprintf(p, "(%lu, %s)",
+				key_inum(c, key), get_key_type(type));
+			break;
+		default:
+			sprintf(p, "(bad key type: %#08x, %#08x)",
+				key->u32[0], key->u32[1]);
+		}
+	} else
+		sprintf(p, "bad key format %d", c->key_fmt);
+}
+
+const char *dbg_key_str0(const struct ubifs_info *c, const union ubifs_key *key)
+{
+	/* dbg_lock must be held */
+	sprintf_key(c, key, dbg_key_buf0);
+	return dbg_key_buf0;
+}
+
+const char *dbg_key_str1(const struct ubifs_info *c, const union ubifs_key *key)
+{
+	/* dbg_lock must be held */
+	sprintf_key(c, key, dbg_key_buf1);
+	return dbg_key_buf1;
+}
+
+const char *dbg_ntype(int type)
+{
+	switch (type) {
+	case UBIFS_PAD_NODE:
+		return "padding node";
+	case UBIFS_SB_NODE:
+		return "superblock node";
+	case UBIFS_MST_NODE:
+		return "master node";
+	case UBIFS_REF_NODE:
+		return "reference node";
+	case UBIFS_INO_NODE:
+		return "inode node";
+	case UBIFS_DENT_NODE:
+		return "direntry node";
+	case UBIFS_XENT_NODE:
+		return "xentry node";
+	case UBIFS_DATA_NODE:
+		return "data node";
+	case UBIFS_TRUN_NODE:
+		return "truncate node";
+	case UBIFS_IDX_NODE:
+		return "indexing node";
+	case UBIFS_CS_NODE:
+		return "commit start node";
+	case UBIFS_ORPH_NODE:
+		return "orphan node";
+	default:
+		return "unknown node";
+	}
+}
+
+static const char *dbg_gtype(int type)
+{
+	switch (type) {
+	case UBIFS_NO_NODE_GROUP:
+		return "no node group";
+	case UBIFS_IN_NODE_GROUP:
+		return "in node group";
+	case UBIFS_LAST_OF_NODE_GROUP:
+		return "last of node group";
+	default:
+		return "unknown";
+	}
+}
+
+const char *dbg_cstate(int cmt_state)
+{
+	switch (cmt_state) {
+	case COMMIT_RESTING:
+		return "commit resting";
+	case COMMIT_BACKGROUND:
+		return "background commit requested";
+	case COMMIT_REQUIRED:
+		return "commit required";
+	case COMMIT_RUNNING_BACKGROUND:
+		return "BACKGROUND commit running";
+	case COMMIT_RUNNING_REQUIRED:
+		return "commit running and required";
+	case COMMIT_BROKEN:
+		return "broken commit";
+	default:
+		return "unknown commit state";
+	}
+}
+
+static void dump_ch(const struct ubifs_ch *ch)
+{
+	printk(KERN_DEBUG "\tmagic          %#x\n", le32_to_cpu(ch->magic));
+	printk(KERN_DEBUG "\tcrc            %#x\n", le32_to_cpu(ch->crc));
+	printk(KERN_DEBUG "\tnode_type      %d (%s)\n", ch->node_type,
+	       dbg_ntype(ch->node_type));
+	printk(KERN_DEBUG "\tgroup_type     %d (%s)\n", ch->group_type,
+	       dbg_gtype(ch->group_type));
+	printk(KERN_DEBUG "\tsqnum          %llu\n",
+	       (unsigned long long)le64_to_cpu(ch->sqnum));
+	printk(KERN_DEBUG "\tlen            %u\n", le32_to_cpu(ch->len));
+}
+
+void dbg_dump_inode(const struct ubifs_info *c, const struct inode *inode)
+{
+	const struct ubifs_inode *ui = ubifs_inode(inode);
+
+	printk(KERN_DEBUG "inode      %lu\n", inode->i_ino);
+	printk(KERN_DEBUG "size       %llu\n",
+	       (unsigned long long)i_size_read(inode));
+	printk(KERN_DEBUG "nlink      %u\n", inode->i_nlink);
+	printk(KERN_DEBUG "uid        %u\n", (unsigned int)inode->i_uid);
+	printk(KERN_DEBUG "gid        %u\n", (unsigned int)inode->i_gid);
+	printk(KERN_DEBUG "atime      %u.%u\n",
+	       (unsigned int)inode->i_atime.tv_sec,
+	       (unsigned int)inode->i_atime.tv_nsec);
+	printk(KERN_DEBUG "mtime      %u.%u\n",
+	       (unsigned int)inode->i_mtime.tv_sec,
+	       (unsigned int)inode->i_mtime.tv_nsec);
+	printk(KERN_DEBUG "ctime       %u.%u\n",
+	       (unsigned int)inode->i_ctime.tv_sec,
+	       (unsigned int)inode->i_ctime.tv_nsec);
+	printk(KERN_DEBUG "creat_sqnum %llu\n", ui->creat_sqnum);
+	printk(KERN_DEBUG "xattr_size  %u\n", ui->xattr_size);
+	printk(KERN_DEBUG "xattr_cnt   %u\n", ui->xattr_cnt);
+	printk(KERN_DEBUG "xattr_names %u\n", ui->xattr_names);
+	printk(KERN_DEBUG "dirty       %u\n", ui->dirty);
+	printk(KERN_DEBUG "xattr       %u\n", ui->xattr);
+	printk(KERN_DEBUG "flags       %d\n", ui->flags);
+	printk(KERN_DEBUG "compr_type  %d\n", ui->compr_type);
+	printk(KERN_DEBUG "data_len    %d\n", ui->data_len);
+}
+
+void dbg_dump_node(const struct ubifs_info *c, const void *node)
+{
+	int i, n;
+	union ubifs_key key;
+	const struct ubifs_ch *ch = node;
+
+	if (dbg_failure_mode)
+		return;
+
+	/* If the magic is incorrect, just hexdump the first bytes */
+	if (le32_to_cpu(ch->magic) != UBIFS_NODE_MAGIC) {
+		printk(KERN_DEBUG "Not a node, first %zu bytes:", UBIFS_CH_SZ);
+		print_hex_dump(KERN_DEBUG, "", DUMP_PREFIX_OFFSET, 32, 1,
+			       (void *)node, UBIFS_CH_SZ, 1);
+		return;
+	}
+
+	spin_lock(&dbg_lock);
+	dump_ch(node);
+
+	switch (ch->node_type) {
+	case UBIFS_PAD_NODE:
+	{
+		const struct ubifs_pad_node *pad = node;
+
+		printk(KERN_DEBUG "\tpad_len        %u\n",
+		       le32_to_cpu(pad->pad_len));
+		break;
+	}
+	case UBIFS_SB_NODE:
+	{
+		const struct ubifs_sb_node *sup = node;
+		unsigned int sup_flags = le32_to_cpu(sup->flags);
+
+		printk(KERN_DEBUG "\tkey_hash       %d (%s)\n",
+		       (int)sup->key_hash, get_key_hash(sup->key_hash));
+		printk(KERN_DEBUG "\tkey_fmt        %d (%s)\n",
+		       (int)sup->key_fmt, get_key_fmt(sup->key_fmt));
+		printk(KERN_DEBUG "\tflags          %#x\n", sup_flags);
+		printk(KERN_DEBUG "\t  big_lpt      %u\n",
+		       !!(sup_flags & UBIFS_FLG_BIGLPT));
+		printk(KERN_DEBUG "\tmin_io_size    %u\n",
+		       le32_to_cpu(sup->min_io_size));
+		printk(KERN_DEBUG "\tleb_size       %u\n",
+		       le32_to_cpu(sup->leb_size));
+		printk(KERN_DEBUG "\tleb_cnt        %u\n",
+		       le32_to_cpu(sup->leb_cnt));
+		printk(KERN_DEBUG "\tmax_leb_cnt    %u\n",
+		       le32_to_cpu(sup->max_leb_cnt));
+		printk(KERN_DEBUG "\tmax_bud_bytes  %llu\n",
+		       (unsigned long long)le64_to_cpu(sup->max_bud_bytes));
+		printk(KERN_DEBUG "\tlog_lebs       %u\n",
+		       le32_to_cpu(sup->log_lebs));
+		printk(KERN_DEBUG "\tlpt_lebs       %u\n",
+		       le32_to_cpu(sup->lpt_lebs));
+		printk(KERN_DEBUG "\torph_lebs      %u\n",
+		       le32_to_cpu(sup->orph_lebs));
+		printk(KERN_DEBUG "\tjhead_cnt      %u\n",
+		       le32_to_cpu(sup->jhead_cnt));
+		printk(KERN_DEBUG "\tfanout         %u\n",
+		       le32_to_cpu(sup->fanout));
+		printk(KERN_DEBUG "\tlsave_cnt      %u\n",
+		       le32_to_cpu(sup->lsave_cnt));
+		printk(KERN_DEBUG "\tdefault_compr  %u\n",
+		       (int)le16_to_cpu(sup->default_compr));
+		printk(KERN_DEBUG "\trp_size        %llu\n",
+		       (unsigned long long)le64_to_cpu(sup->rp_size));
+		printk(KERN_DEBUG "\trp_uid         %u\n",
+		       le32_to_cpu(sup->rp_uid));
+		printk(KERN_DEBUG "\trp_gid         %u\n",
+		       le32_to_cpu(sup->rp_gid));
+		printk(KERN_DEBUG "\tfmt_version    %u\n",
+		       le32_to_cpu(sup->fmt_version));
+		printk(KERN_DEBUG "\ttime_gran      %u\n",
+		       le32_to_cpu(sup->time_gran));
+		printk(KERN_DEBUG "\tUUID           %02X%02X%02X%02X-%02X%02X"
+		       "-%02X%02X-%02X%02X-%02X%02X%02X%02X%02X%02X\n",
+		       sup->uuid[0], sup->uuid[1], sup->uuid[2], sup->uuid[3],
+		       sup->uuid[4], sup->uuid[5], sup->uuid[6], sup->uuid[7],
+		       sup->uuid[8], sup->uuid[9], sup->uuid[10], sup->uuid[11],
+		       sup->uuid[12], sup->uuid[13], sup->uuid[14],
+		       sup->uuid[15]);
+		break;
+	}
+	case UBIFS_MST_NODE:
+	{
+		const struct ubifs_mst_node *mst = node;
+
+		printk(KERN_DEBUG "\thighest_inum   %llu\n",
+		       (unsigned long long)le64_to_cpu(mst->highest_inum));
+		printk(KERN_DEBUG "\tcommit number  %llu\n",
+		       (unsigned long long)le64_to_cpu(mst->cmt_no));
+		printk(KERN_DEBUG "\tflags          %#x\n",
+		       le32_to_cpu(mst->flags));
+		printk(KERN_DEBUG "\tlog_lnum       %u\n",
+		       le32_to_cpu(mst->log_lnum));
+		printk(KERN_DEBUG "\troot_lnum      %u\n",
+		       le32_to_cpu(mst->root_lnum));
+		printk(KERN_DEBUG "\troot_offs      %u\n",
+		       le32_to_cpu(mst->root_offs));
+		printk(KERN_DEBUG "\troot_len       %u\n",
+		       le32_to_cpu(mst->root_len));
+		printk(KERN_DEBUG "\tgc_lnum        %u\n",
+		       le32_to_cpu(mst->gc_lnum));
+		printk(KERN_DEBUG "\tihead_lnum     %u\n",
+		       le32_to_cpu(mst->ihead_lnum));
+		printk(KERN_DEBUG "\tihead_offs     %u\n",
+		       le32_to_cpu(mst->ihead_offs));
+		printk(KERN_DEBUG "\tindex_size     %u\n",
+		       le32_to_cpu(mst->index_size));
+		printk(KERN_DEBUG "\tlpt_lnum       %u\n",
+		       le32_to_cpu(mst->lpt_lnum));
+		printk(KERN_DEBUG "\tlpt_offs       %u\n",
+		       le32_to_cpu(mst->lpt_offs));
+		printk(KERN_DEBUG "\tnhead_lnum     %u\n",
+		       le32_to_cpu(mst->nhead_lnum));
+		printk(KERN_DEBUG "\tnhead_offs     %u\n",
+		       le32_to_cpu(mst->nhead_offs));
+		printk(KERN_DEBUG "\tltab_lnum      %u\n",
+		       le32_to_cpu(mst->ltab_lnum));
+		printk(KERN_DEBUG "\tltab_offs      %u\n",
+		       le32_to_cpu(mst->ltab_offs));
+		printk(KERN_DEBUG "\tlsave_lnum     %u\n",
+		       le32_to_cpu(mst->lsave_lnum));
+		printk(KERN_DEBUG "\tlsave_offs     %u\n",
+		       le32_to_cpu(mst->lsave_offs));
+		printk(KERN_DEBUG "\tlscan_lnum     %u\n",
+		       le32_to_cpu(mst->lscan_lnum));
+		printk(KERN_DEBUG "\tleb_cnt        %u\n",
+		       le32_to_cpu(mst->leb_cnt));
+		printk(KERN_DEBUG "\tempty_lebs     %u\n",
+		       le32_to_cpu(mst->empty_lebs));
+		printk(KERN_DEBUG "\tidx_lebs       %u\n",
+		       le32_to_cpu(mst->idx_lebs));
+		printk(KERN_DEBUG "\ttotal_free     %llu\n",
+		       (unsigned long long)le64_to_cpu(mst->total_free));
+		printk(KERN_DEBUG "\ttotal_dirty    %llu\n",
+		       (unsigned long long)le64_to_cpu(mst->total_dirty));
+		printk(KERN_DEBUG "\ttotal_used     %llu\n",
+		       (unsigned long long)le64_to_cpu(mst->total_used));
+		printk(KERN_DEBUG "\ttotal_dead     %llu\n",
+		       (unsigned long long)le64_to_cpu(mst->total_dead));
+		printk(KERN_DEBUG "\ttotal_dark     %llu\n",
+		       (unsigned long long)le64_to_cpu(mst->total_dark));
+		break;
+	}
+	case UBIFS_REF_NODE:
+	{
+		const struct ubifs_ref_node *ref = node;
+
+		printk(KERN_DEBUG "\tlnum           %u\n",
+		       le32_to_cpu(ref->lnum));
+		printk(KERN_DEBUG "\toffs           %u\n",
+		       le32_to_cpu(ref->offs));
+		printk(KERN_DEBUG "\tjhead          %u\n",
+		       le32_to_cpu(ref->jhead));
+		break;
+	}
+	case UBIFS_INO_NODE:
+	{
+		const struct ubifs_ino_node *ino = node;
+
+		key_read(c, &ino->key, &key);
+		printk(KERN_DEBUG "\tkey            %s\n", DBGKEY(&key));
+		printk(KERN_DEBUG "\tcreat_sqnum    %llu\n",
+		       (unsigned long long)le64_to_cpu(ino->creat_sqnum));
+		printk(KERN_DEBUG "\tsize           %llu\n",
+		       (unsigned long long)le64_to_cpu(ino->size));
+		printk(KERN_DEBUG "\tnlink          %u\n",
+		       le32_to_cpu(ino->nlink));
+		printk(KERN_DEBUG "\tatime          %lld.%u\n",
+		       (long long)le64_to_cpu(ino->atime_sec),
+		       le32_to_cpu(ino->atime_nsec));
+		printk(KERN_DEBUG "\tmtime          %lld.%u\n",
+		       (long long)le64_to_cpu(ino->mtime_sec),
+		       le32_to_cpu(ino->mtime_nsec));
+		printk(KERN_DEBUG "\tctime          %lld.%u\n",
+		       (long long)le64_to_cpu(ino->ctime_sec),
+		       le32_to_cpu(ino->ctime_nsec));
+		printk(KERN_DEBUG "\tuid            %u\n",
+		       le32_to_cpu(ino->uid));
+		printk(KERN_DEBUG "\tgid            %u\n",
+		       le32_to_cpu(ino->gid));
+		printk(KERN_DEBUG "\tmode           %u\n",
+		       le32_to_cpu(ino->mode));
+		printk(KERN_DEBUG "\tflags          %#x\n",
+		       le32_to_cpu(ino->flags));
+		printk(KERN_DEBUG "\txattr_cnt      %u\n",
+		       le32_to_cpu(ino->xattr_cnt));
+		printk(KERN_DEBUG "\txattr_size     %u\n",
+		       le32_to_cpu(ino->xattr_size));
+		printk(KERN_DEBUG "\txattr_names    %u\n",
+		       le32_to_cpu(ino->xattr_names));
+		printk(KERN_DEBUG "\tcompr_type     %#x\n",
+		       (int)le16_to_cpu(ino->compr_type));
+		printk(KERN_DEBUG "\tdata len       %u\n",
+		       le32_to_cpu(ino->data_len));
+		break;
+	}
+	case UBIFS_DENT_NODE:
+	case UBIFS_XENT_NODE:
+	{
+		const struct ubifs_dent_node *dent = node;
+		int nlen = le16_to_cpu(dent->nlen);
+
+		key_read(c, &dent->key, &key);
+		printk(KERN_DEBUG "\tkey            %s\n", DBGKEY(&key));
+		printk(KERN_DEBUG "\tinum           %llu\n",
+		       (unsigned long long)le64_to_cpu(dent->inum));
+		printk(KERN_DEBUG "\ttype           %d\n", (int)dent->type);
+		printk(KERN_DEBUG "\tnlen           %d\n", nlen);
+		printk(KERN_DEBUG "\tname           ");
+
+		if (nlen > UBIFS_MAX_NLEN)
+			printk(KERN_DEBUG "(bad name length, not printing, "
+					  "bad or corrupted node)");
+		else {
+			for (i = 0; i < nlen && dent->name[i]; i++)
+				printk("%c", dent->name[i]);
+		}
+		printk("\n");
+
+		break;
+	}
+	case UBIFS_DATA_NODE:
+	{
+		const struct ubifs_data_node *dn = node;
+		int dlen = le32_to_cpu(ch->len) - UBIFS_DATA_NODE_SZ;
+
+		key_read(c, &dn->key, &key);
+		printk(KERN_DEBUG "\tkey            %s\n", DBGKEY(&key));
+		printk(KERN_DEBUG "\tsize           %u\n",
+		       le32_to_cpu(dn->size));
+		printk(KERN_DEBUG "\tcompr_typ      %d\n",
+		       (int)le16_to_cpu(dn->compr_type));
+		printk(KERN_DEBUG "\tdata size      %d\n",
+		       dlen);
+		printk(KERN_DEBUG "\tdata:\n");
+		print_hex_dump(KERN_DEBUG, "\t", DUMP_PREFIX_OFFSET, 32, 1,
+			       (void *)&dn->data, dlen, 0);
+		break;
+	}
+	case UBIFS_TRUN_NODE:
+	{
+		const struct ubifs_trun_node *trun = node;
+
+		printk(KERN_DEBUG "\tinum           %u\n",
+		       le32_to_cpu(trun->inum));
+		printk(KERN_DEBUG "\told_size       %llu\n",
+		       (unsigned long long)le64_to_cpu(trun->old_size));
+		printk(KERN_DEBUG "\tnew_size       %llu\n",
+		       (unsigned long long)le64_to_cpu(trun->new_size));
+		break;
+	}
+	case UBIFS_IDX_NODE:
+	{
+		const struct ubifs_idx_node *idx = node;
+
+		n = le16_to_cpu(idx->child_cnt);
+		printk(KERN_DEBUG "\tchild_cnt      %d\n", n);
+		printk(KERN_DEBUG "\tlevel          %d\n",
+		       (int)le16_to_cpu(idx->level));
+		printk(KERN_DEBUG "\tBranches:\n");
+
+		for (i = 0; i < n && i < c->fanout - 1; i++) {
+			const struct ubifs_branch *br;
+
+			br = ubifs_idx_branch(c, idx, i);
+			key_read(c, &br->key, &key);
+			printk(KERN_DEBUG "\t%d: LEB %d:%d len %d key %s\n",
+			       i, le32_to_cpu(br->lnum), le32_to_cpu(br->offs),
+			       le32_to_cpu(br->len), DBGKEY(&key));
+		}
+		break;
+	}
+	case UBIFS_CS_NODE:
+		break;
+	case UBIFS_ORPH_NODE:
+	{
+		const struct ubifs_orph_node *orph = node;
+
+		printk(KERN_DEBUG "\tcommit number  %llu\n",
+		       (unsigned long long)
+				le64_to_cpu(orph->cmt_no) & LLONG_MAX);
+		printk(KERN_DEBUG "\tlast node flag %llu\n",
+		       (unsigned long long)(le64_to_cpu(orph->cmt_no)) >> 63);
+		n = (le32_to_cpu(ch->len) - UBIFS_ORPH_NODE_SZ) >> 3;
+		printk(KERN_DEBUG "\t%d orphan inode numbers:\n", n);
+		for (i = 0; i < n; i++)
+			printk(KERN_DEBUG "\t  ino %llu\n",
+			       le64_to_cpu(orph->inos[i]));
+		break;
+	}
+	default:
+		printk(KERN_DEBUG "node type %d was not recognized\n",
+		       (int)ch->node_type);
+	}
+	spin_unlock(&dbg_lock);
+}
+
+void dbg_dump_budget_req(const struct ubifs_budget_req *req)
+{
+	spin_lock(&dbg_lock);
+	printk(KERN_DEBUG "Budgeting request: new_ino %d, dirtied_ino %d\n",
+	       req->new_ino, req->dirtied_ino);
+	printk(KERN_DEBUG "\tnew_ino_d   %d, dirtied_ino_d %d\n",
+	       req->new_ino_d, req->dirtied_ino_d);
+	printk(KERN_DEBUG "\tnew_page    %d, dirtied_page %d\n",
+	       req->new_page, req->dirtied_page);
+	printk(KERN_DEBUG "\tnew_dent    %d, mod_dent     %d\n",
+	       req->new_dent, req->mod_dent);
+	printk(KERN_DEBUG "\tidx_growth  %d\n", req->idx_growth);
+	printk(KERN_DEBUG "\tdata_growth %d dd_growth     %d\n",
+	       req->data_growth, req->dd_growth);
+	spin_unlock(&dbg_lock);
+}
+
+void dbg_dump_lstats(const struct ubifs_lp_stats *lst)
+{
+	spin_lock(&dbg_lock);
+	printk(KERN_DEBUG "Lprops statistics: empty_lebs %d, idx_lebs  %d\n",
+	       lst->empty_lebs, lst->idx_lebs);
+	printk(KERN_DEBUG "\ttaken_empty_lebs %d, total_free %lld, "
+	       "total_dirty %lld\n", lst->taken_empty_lebs, lst->total_free,
+	       lst->total_dirty);
+	printk(KERN_DEBUG "\ttotal_used %lld, total_dark %lld, "
+	       "total_dead %lld\n", lst->total_used, lst->total_dark,
+	       lst->total_dead);
+	spin_unlock(&dbg_lock);
+}
+
+void dbg_dump_budg(struct ubifs_info *c)
+{
+	int i;
+	struct rb_node *rb;
+	struct ubifs_bud *bud;
+	struct ubifs_gced_idx_leb *idx_gc;
+
+	spin_lock(&dbg_lock);
+	printk(KERN_DEBUG "Budgeting info: budg_data_growth %lld, "
+	       "budg_dd_growth %lld, budg_idx_growth %lld\n",
+	       c->budg_data_growth, c->budg_dd_growth, c->budg_idx_growth);
+	printk(KERN_DEBUG "\tdata budget sum %lld, total budget sum %lld, "
+	       "freeable_cnt %d\n", c->budg_data_growth + c->budg_dd_growth,
+	       c->budg_data_growth + c->budg_dd_growth + c->budg_idx_growth,
+	       c->freeable_cnt);
+	printk(KERN_DEBUG "\tmin_idx_lebs %d, old_idx_sz %lld, "
+	       "calc_idx_sz %lld, idx_gc_cnt %d\n", c->min_idx_lebs,
+	       c->old_idx_sz, c->calc_idx_sz, c->idx_gc_cnt);
+	printk(KERN_DEBUG "\tdirty_pg_cnt %ld, dirty_zn_cnt %ld, "
+	       "clean_zn_cnt %ld\n", atomic_long_read(&c->dirty_pg_cnt),
+	       atomic_long_read(&c->dirty_zn_cnt),
+	       atomic_long_read(&c->clean_zn_cnt));
+	printk(KERN_DEBUG "\tdark_wm %d, dead_wm %d, max_idx_node_sz %d\n",
+	       c->dark_wm, c->dead_wm, c->max_idx_node_sz);
+	printk(KERN_DEBUG "\tgc_lnum %d, ihead_lnum %d\n",
+	       c->gc_lnum, c->ihead_lnum);
+	for (i = 0; i < c->jhead_cnt; i++)
+		printk(KERN_DEBUG "\tjhead %d\t LEB %d\n",
+		       c->jheads[i].wbuf.jhead, c->jheads[i].wbuf.lnum);
+	for (rb = rb_first(&c->buds); rb; rb = rb_next(rb)) {
+		bud = rb_entry(rb, struct ubifs_bud, rb);
+		printk(KERN_DEBUG "\tbud LEB %d\n", bud->lnum);
+	}
+	list_for_each_entry(bud, &c->old_buds, list)
+		printk(KERN_DEBUG "\told bud LEB %d\n", bud->lnum);
+	list_for_each_entry(idx_gc, &c->idx_gc, list)
+		printk(KERN_DEBUG "\tGC'ed idx LEB %d unmap %d\n",
+		       idx_gc->lnum, idx_gc->unmap);
+	printk(KERN_DEBUG "\tcommit state %d\n", c->cmt_state);
+	spin_unlock(&dbg_lock);
+}
+
+void dbg_dump_lprop(const struct ubifs_info *c, const struct ubifs_lprops *lp)
+{
+	printk(KERN_DEBUG "LEB %d lprops: free %d, dirty %d (used %d), "
+	       "flags %#x\n", lp->lnum, lp->free, lp->dirty,
+	       c->leb_size - lp->free - lp->dirty, lp->flags);
+}
+
+void dbg_dump_lprops(struct ubifs_info *c)
+{
+	int lnum, err;
+	struct ubifs_lprops lp;
+	struct ubifs_lp_stats lst;
+
+	printk(KERN_DEBUG "Dumping LEB properties\n");
+	ubifs_get_lp_stats(c, &lst);
+	dbg_dump_lstats(&lst);
+
+	for (lnum = c->main_first; lnum < c->leb_cnt; lnum++) {
+		err = ubifs_read_one_lp(c, lnum, &lp);
+		if (err)
+			ubifs_err("cannot read lprops for LEB %d", lnum);
+
+		dbg_dump_lprop(c, &lp);
+	}
+}
+
+void dbg_dump_leb(const struct ubifs_info *c, int lnum)
+{
+	struct ubifs_scan_leb *sleb;
+	struct ubifs_scan_node *snod;
+
+	if (dbg_failure_mode)
+		return;
+
+	printk(KERN_DEBUG "Dumping LEB %d\n", lnum);
+
+	sleb = ubifs_scan(c, lnum, 0, c->dbg_buf);
+	if (IS_ERR(sleb)) {
+		ubifs_err("scan error %d", (int)PTR_ERR(sleb));
+		return;
+	}
+
+	printk(KERN_DEBUG "LEB %d has %d nodes ending at %d\n", lnum,
+	       sleb->nodes_cnt, sleb->endpt);
+
+	list_for_each_entry(snod, &sleb->nodes, list) {
+		cond_resched();
+		printk(KERN_DEBUG "Dumping node at LEB %d:%d len %d\n", lnum,
+		       snod->offs, snod->len);
+		dbg_dump_node(c, snod->node);
+	}
+
+	ubifs_scan_destroy(sleb);
+	return;
+}
+
+void dbg_dump_znode(const struct ubifs_info *c,
+		    const struct ubifs_znode *znode)
+{
+	int n;
+	const struct ubifs_zbranch *zbr;
+
+	spin_lock(&dbg_lock);
+	if (znode->parent)
+		zbr = &znode->parent->zbranch[znode->iip];
+	else
+		zbr = &c->zroot;
+
+	printk(KERN_DEBUG "znode %p, LEB %d:%d len %d parent %p iip %d level %d"
+	       " child_cnt %d flags %lx\n", znode, zbr->lnum, zbr->offs,
+	       zbr->len, znode->parent, znode->iip, znode->level,
+	       znode->child_cnt, znode->flags);
+
+	if (znode->child_cnt <= 0 || znode->child_cnt > c->fanout) {
+		spin_unlock(&dbg_lock);
+		return;
+	}
+
+	printk(KERN_DEBUG "zbranches:\n");
+	for (n = 0; n < znode->child_cnt; n++) {
+		zbr = &znode->zbranch[n];
+		if (znode->level > 0)
+			printk(KERN_DEBUG "\t%d: znode %p LEB %d:%d len %d key "
+					  "%s\n", n, zbr->znode, zbr->lnum,
+					  zbr->offs, zbr->len,
+					  DBGKEY(&zbr->key));
+		else
+			printk(KERN_DEBUG "\t%d: LNC %p LEB %d:%d len %d key "
+					  "%s\n", n, zbr->znode, zbr->lnum,
+					  zbr->offs, zbr->len,
+					  DBGKEY(&zbr->key));
+	}
+	spin_unlock(&dbg_lock);
+}
+
+void dbg_dump_heap(struct ubifs_info *c, struct ubifs_lpt_heap *heap, int cat)
+{
+	int i;
+
+	printk(KERN_DEBUG "Dumping heap cat %d (%d elements)\n",
+	       cat, heap->cnt);
+	for (i = 0; i < heap->cnt; i++) {
+		struct ubifs_lprops *lprops = heap->arr[i];
+
+		printk(KERN_DEBUG "\t%d. LEB %d hpos %d free %d dirty %d "
+		       "flags %d\n", i, lprops->lnum, lprops->hpos,
+		       lprops->free, lprops->dirty, lprops->flags);
+	}
+}
+
+void dbg_dump_pnode(struct ubifs_info *c, struct ubifs_pnode *pnode,
+		    struct ubifs_nnode *parent, int iip)
+{
+	int i;
+
+	printk(KERN_DEBUG "Dumping pnode:\n");
+	printk(KERN_DEBUG "\taddress %zx parent %zx cnext %zx\n",
+	       (size_t)pnode, (size_t)parent, (size_t)pnode->cnext);
+	printk(KERN_DEBUG "\tflags %lu iip %d level %d num %d\n",
+	       pnode->flags, iip, pnode->level, pnode->num);
+	for (i = 0; i < UBIFS_LPT_FANOUT; i++) {
+		struct ubifs_lprops *lp = &pnode->lprops[i];
+
+		printk(KERN_DEBUG "\t%d: free %d dirty %d flags %d lnum %d\n",
+		       i, lp->free, lp->dirty, lp->flags, lp->lnum);
+	}
+}
+
+void dbg_dump_tnc(struct ubifs_info *c)
+{
+	struct ubifs_znode *znode;
+	int level;
+
+	printk(KERN_DEBUG "\n");
+	printk(KERN_DEBUG "Dumping the TNC tree\n");
+	znode = ubifs_tnc_levelorder_next(c->zroot.znode, NULL);
+	level = znode->level;
+	printk(KERN_DEBUG "== Level %d ==\n", level);
+	while (znode) {
+		if (level != znode->level) {
+			level = znode->level;
+			printk(KERN_DEBUG "== Level %d ==\n", level);
+		}
+		dbg_dump_znode(c, znode);
+		znode = ubifs_tnc_levelorder_next(c->zroot.znode, znode);
+	}
+
+	printk(KERN_DEBUG "\n");
+}
+
+static int dump_znode(struct ubifs_info *c, struct ubifs_znode *znode,
+		      void *priv)
+{
+	dbg_dump_znode(c, znode);
+	return 0;
+}
+
+/**
+ * dbg_dump_index - dump the on-flash index.
+ * @c: UBIFS file-system description object
+ *
+ * This function dumps whole UBIFS indexing B-tree, unlike 'dbg_dump_tnc()'
+ * which dumps only in-memory znodes and does not read znodes which from flash.
+ */
+void dbg_dump_index(struct ubifs_info *c)
+{
+	dbg_walk_index(c, NULL, dump_znode, NULL);
+}
+
+/**
+ * dbg_check_synced_i_size - check synchronized inode size.
+ * @inode: inode to check
+ *
+ * If inode is clean, synchronized inode size has to be equivalent to current
+ * inode size. This function has to be called only for locked inodes (@i_mutex
+ * has to be locked). Returns %0 if synchronized inode size if correct, and
+ * %-EINVAL if not.
+ */
+int dbg_check_synced_i_size(struct inode *inode)
+{
+	int err = 0;
+	struct ubifs_inode *ui = ubifs_inode(inode);
+
+	if (!(ubifs_chk_flags & UBIFS_CHK_GEN))
+		return 0;
+	if (!S_ISREG(inode->i_mode))
+		return 0;
+
+	mutex_lock(&ui->ui_mutex);
+	spin_lock(&ui->ui_lock);
+	if (ui->ui_size != ui->synced_i_size && !ui->dirty) {
+		ubifs_err("ui_size is %lld, synced_i_size is %lld, but inode "
+			  "is clean", ui->ui_size, ui->synced_i_size);
+		ubifs_err("i_ino %lu, i_mode %#x, i_size %lld", inode->i_ino,
+			  inode->i_mode, i_size_read(inode));
+		dbg_dump_stack();
+		err = -EINVAL;
+	}
+	spin_unlock(&ui->ui_lock);
+	mutex_unlock(&ui->ui_mutex);
+	return err;
+}
+
+/*
+ * dbg_check_dir - check directory inode size and link count.
+ * @c: UBIFS file-system description object
+ * @dir: the directory to calculate size for
+ * @size: the result is returned here
+ *
+ * This function makes sure that directory size and link count are correct.
+ * Returns zero in case of success and a negative error code in case of
+ * failure.
+ *
+ * Note, it is good idea to make sure the @dir->i_mutex is locked before
+ * calling this function.
+ */
+int dbg_check_dir_size(struct ubifs_info *c, const struct inode *dir)
+{
+	unsigned int nlink = 2;
+	union ubifs_key key;
+	struct ubifs_dent_node *dent, *pdent = NULL;
+	struct qstr nm = { .name = NULL };
+	loff_t size = UBIFS_INO_NODE_SZ;
+
+	if (!(ubifs_chk_flags & UBIFS_CHK_GEN))
+		return 0;
+
+	if (!S_ISDIR(dir->i_mode))
+		return 0;
+
+	lowest_dent_key(c, &key, dir->i_ino);
+	while (1) {
+		int err;
+
+		dent = ubifs_tnc_next_ent(c, &key, &nm);
+		if (IS_ERR(dent)) {
+			err = PTR_ERR(dent);
+			if (err == -ENOENT)
+				break;
+			return err;
+		}
+
+		nm.name = dent->name;
+		nm.len = le16_to_cpu(dent->nlen);
+		size += CALC_DENT_SIZE(nm.len);
+		if (dent->type == UBIFS_ITYPE_DIR)
+			nlink += 1;
+		kfree(pdent);
+		pdent = dent;
+		key_read(c, &dent->key, &key);
+	}
+	kfree(pdent);
+
+	if (i_size_read(dir) != size) {
+		ubifs_err("directory inode %lu has size %llu, "
+			  "but calculated size is %llu", dir->i_ino,
+			  (unsigned long long)i_size_read(dir),
+			  (unsigned long long)size);
+		dump_stack();
+		return -EINVAL;
+	}
+	if (dir->i_nlink != nlink) {
+		ubifs_err("directory inode %lu has nlink %u, but calculated "
+			  "nlink is %u", dir->i_ino, dir->i_nlink, nlink);
+		dump_stack();
+		return -EINVAL;
+	}
+
+	return 0;
+}
+
+/**
+ * dbg_check_key_order - make sure that colliding keys are properly ordered.
+ * @c: UBIFS file-system description object
+ * @zbr1: first zbranch
+ * @zbr2: following zbranch
+ *
+ * In UBIFS indexing B-tree colliding keys has to be sorted in binary order of
+ * names of the direntries/xentries which are referred by the keys. This
+ * function reads direntries/xentries referred by @zbr1 and @zbr2 and makes
+ * sure the name of direntry/xentry referred by @zbr1 is less than
+ * direntry/xentry referred by @zbr2. Returns zero if this is true, %1 if not,
+ * and a negative error code in case of failure.
+ */
+static int dbg_check_key_order(struct ubifs_info *c, struct ubifs_zbranch *zbr1,
+			       struct ubifs_zbranch *zbr2)
+{
+	int err, nlen1, nlen2, cmp;
+	struct ubifs_dent_node *dent1, *dent2;
+	union ubifs_key key;
+
+	ubifs_assert(!keys_cmp(c, &zbr1->key, &zbr2->key));
+	dent1 = kmalloc(UBIFS_MAX_DENT_NODE_SZ, GFP_NOFS);
+	if (!dent1)
+		return -ENOMEM;
+	dent2 = kmalloc(UBIFS_MAX_DENT_NODE_SZ, GFP_NOFS);
+	if (!dent2) {
+		err = -ENOMEM;
+		goto out_free;
+	}
+
+	err = ubifs_tnc_read_node(c, zbr1, dent1);
+	if (err)
+		goto out_free;
+	err = ubifs_validate_entry(c, dent1);
+	if (err)
+		goto out_free;
+
+	err = ubifs_tnc_read_node(c, zbr2, dent2);
+	if (err)
+		goto out_free;
+	err = ubifs_validate_entry(c, dent2);
+	if (err)
+		goto out_free;
+
+	/* Make sure node keys are the same as in zbranch */
+	err = 1;
+	key_read(c, &dent1->key, &key);
+	if (keys_cmp(c, &zbr1->key, &key)) {
+		dbg_err("1st entry at %d:%d has key %s", zbr1->lnum,
+			zbr1->offs, DBGKEY(&key));
+		dbg_err("but it should have key %s according to tnc",
+			DBGKEY(&zbr1->key));
+			dbg_dump_node(c, dent1);
+			goto out_free;
+	}
+
+	key_read(c, &dent2->key, &key);
+	if (keys_cmp(c, &zbr2->key, &key)) {
+		dbg_err("2nd entry at %d:%d has key %s", zbr1->lnum,
+			zbr1->offs, DBGKEY(&key));
+		dbg_err("but it should have key %s according to tnc",
+			DBGKEY(&zbr2->key));
+			dbg_dump_node(c, dent2);
+			goto out_free;
+	}
+
+	nlen1 = le16_to_cpu(dent1->nlen);
+	nlen2 = le16_to_cpu(dent2->nlen);
+
+	cmp = memcmp(dent1->name, dent2->name, min_t(int, nlen1, nlen2));
+	if (cmp < 0 || (cmp == 0 && nlen1 < nlen2)) {
+		err = 0;
+		goto out_free;
+	}
+	if (cmp == 0 && nlen1 == nlen2)
+		dbg_err("2 xent/dent nodes with the same name");
+	else
+		dbg_err("bad order of colliding key %s",
+			DBGKEY(&key));
+
+	dbg_msg("first node at %d:%d\n", zbr1->lnum, zbr1->offs);
+	dbg_dump_node(c, dent1);
+	dbg_msg("second node at %d:%d\n", zbr2->lnum, zbr2->offs);
+	dbg_dump_node(c, dent2);
+
+out_free:
+	kfree(dent2);
+	kfree(dent1);
+	return err;
+}
+
+/**
+ * dbg_check_znode - check if znode is all right.
+ * @c: UBIFS file-system description object
+ * @zbr: zbranch which points to this znode
+ *
+ * This function makes sure that znode referred to by @zbr is all right.
+ * Returns zero if it is, and %-EINVAL if it is not.
+ */
+static int dbg_check_znode(struct ubifs_info *c, struct ubifs_zbranch *zbr)
+{
+	struct ubifs_znode *znode = zbr->znode;
+	struct ubifs_znode *zp = znode->parent;
+	int n, err, cmp;
+
+	if (znode->child_cnt <= 0 || znode->child_cnt > c->fanout) {
+		err = 1;
+		goto out;
+	}
+	if (znode->level < 0) {
+		err = 2;
+		goto out;
+	}
+	if (znode->iip < 0 || znode->iip >= c->fanout) {
+		err = 3;
+		goto out;
+	}
+
+	if (zbr->len == 0)
+		/* Only dirty zbranch may have no on-flash nodes */
+		if (!ubifs_zn_dirty(znode)) {
+			err = 4;
+			goto out;
+		}
+
+	if (ubifs_zn_dirty(znode)) {
+		/*
+		 * If znode is dirty, its parent has to be dirty as well. The
+		 * order of the operation is important, so we have to have
+		 * memory barriers.
+		 */
+		smp_mb();
+		if (zp && !ubifs_zn_dirty(zp)) {
+			/*
+			 * The dirty flag is atomic and is cleared outside the
+			 * TNC mutex, so znode's dirty flag may now have
+			 * been cleared. The child is always cleared before the
+			 * parent, so we just need to check again.
+			 */
+			smp_mb();
+			if (ubifs_zn_dirty(znode)) {
+				err = 5;
+				goto out;
+			}
+		}
+	}
+
+	if (zp) {
+		const union ubifs_key *min, *max;
+
+		if (znode->level != zp->level - 1) {
+			err = 6;
+			goto out;
+		}
+
+		/* Make sure the 'parent' pointer in our znode is correct */
+		err = ubifs_search_zbranch(c, zp, &zbr->key, &n);
+		if (!err) {
+			/* This zbranch does not exist in the parent */
+			err = 7;
+			goto out;
+		}
+
+		if (znode->iip >= zp->child_cnt) {
+			err = 8;
+			goto out;
+		}
+
+		if (znode->iip != n) {
+			/* This may happen only in case of collisions */
+			if (keys_cmp(c, &zp->zbranch[n].key,
+				     &zp->zbranch[znode->iip].key)) {
+				err = 9;
+				goto out;
+			}
+			n = znode->iip;
+		}
+
+		/*
+		 * Make sure that the first key in our znode is greater than or
+		 * equal to the key in the pointing zbranch.
+		 */
+		min = &zbr->key;
+		cmp = keys_cmp(c, min, &znode->zbranch[0].key);
+		if (cmp == 1) {
+			err = 10;
+			goto out;
+		}
+
+		if (n + 1 < zp->child_cnt) {
+			max = &zp->zbranch[n + 1].key;
+
+			/*
+			 * Make sure the last key in our znode is less or
+			 * equivalent than the the key in zbranch which goes
+			 * after our pointing zbranch.
+			 */
+			cmp = keys_cmp(c, max,
+				&znode->zbranch[znode->child_cnt - 1].key);
+			if (cmp == -1) {
+				err = 11;
+				goto out;
+			}
+		}
+	} else {
+		/* This may only be root znode */
+		if (zbr != &c->zroot) {
+			err = 12;
+			goto out;
+		}
+	}
+
+	/*
+	 * Make sure that next key is greater or equivalent then the previous
+	 * one.
+	 */
+	for (n = 1; n < znode->child_cnt; n++) {
+		cmp = keys_cmp(c, &znode->zbranch[n - 1].key,
+			       &znode->zbranch[n].key);
+		if (cmp > 0) {
+			err = 13;
+			goto out;
+		}
+		if (cmp == 0) {
+			/* This can only be keys with colliding hash */
+			if (!is_hash_key(c, &znode->zbranch[n].key)) {
+				err = 14;
+				goto out;
+			}
+
+			if (znode->level != 0 || c->replaying)
+				continue;
+
+			/*
+			 * Colliding keys should follow binary order of
+			 * corresponding xentry/dentry names.
+			 */
+			err = dbg_check_key_order(c, &znode->zbranch[n - 1],
+						  &znode->zbranch[n]);
+			if (err < 0)
+				return err;
+			if (err) {
+				err = 15;
+				goto out;
+			}
+		}
+	}
+
+	for (n = 0; n < znode->child_cnt; n++) {
+		if (!znode->zbranch[n].znode &&
+		    (znode->zbranch[n].lnum == 0 ||
+		     znode->zbranch[n].len == 0)) {
+			err = 16;
+			goto out;
+		}
+
+		if (znode->zbranch[n].lnum != 0 &&
+		    znode->zbranch[n].len == 0) {
+			err = 17;
+			goto out;
+		}
+
+		if (znode->zbranch[n].lnum == 0 &&
+		    znode->zbranch[n].len != 0) {
+			err = 18;
+			goto out;
+		}
+
+		if (znode->zbranch[n].lnum == 0 &&
+		    znode->zbranch[n].offs != 0) {
+			err = 19;
+			goto out;
+		}
+
+		if (znode->level != 0 && znode->zbranch[n].znode)
+			if (znode->zbranch[n].znode->parent != znode) {
+				err = 20;
+				goto out;
+			}
+	}
+
+	return 0;
+
+out:
+	ubifs_err("failed, error %d", err);
+	ubifs_msg("dump of the znode");
+	dbg_dump_znode(c, znode);
+	if (zp) {
+		ubifs_msg("dump of the parent znode");
+		dbg_dump_znode(c, zp);
+	}
+	dump_stack();
+	return -EINVAL;
+}
+
+/**
+ * dbg_check_tnc - check TNC tree.
+ * @c: UBIFS file-system description object
+ * @extra: do extra checks that are possible at start commit
+ *
+ * This function traverses whole TNC tree and checks every znode. Returns zero
+ * if everything is all right and %-EINVAL if something is wrong with TNC.
+ */
+int dbg_check_tnc(struct ubifs_info *c, int extra)
+{
+	struct ubifs_znode *znode;
+	long clean_cnt = 0, dirty_cnt = 0;
+	int err, last;
+
+	if (!(ubifs_chk_flags & UBIFS_CHK_TNC))
+		return 0;
+
+	ubifs_assert(mutex_is_locked(&c->tnc_mutex));
+	if (!c->zroot.znode)
+		return 0;
+
+	znode = ubifs_tnc_postorder_first(c->zroot.znode);
+	while (1) {
+		struct ubifs_znode *prev;
+		struct ubifs_zbranch *zbr;
+
+		if (!znode->parent)
+			zbr = &c->zroot;
+		else
+			zbr = &znode->parent->zbranch[znode->iip];
+
+		err = dbg_check_znode(c, zbr);
+		if (err)
+			return err;
+
+		if (extra) {
+			if (ubifs_zn_dirty(znode))
+				dirty_cnt += 1;
+			else
+				clean_cnt += 1;
+		}
+
+		prev = znode;
+		znode = ubifs_tnc_postorder_next(znode);
+		if (!znode)
+			break;
+
+		/*
+		 * If the last key of this znode is equivalent to the first key
+		 * of the next znode (collision), then check order of the keys.
+		 */
+		last = prev->child_cnt - 1;
+		if (prev->level == 0 && znode->level == 0 && !c->replaying &&
+		    !keys_cmp(c, &prev->zbranch[last].key,
+			      &znode->zbranch[0].key)) {
+			err = dbg_check_key_order(c, &prev->zbranch[last],
+						  &znode->zbranch[0]);
+			if (err < 0)
+				return err;
+			if (err) {
+				ubifs_msg("first znode");
+				dbg_dump_znode(c, prev);
+				ubifs_msg("second znode");
+				dbg_dump_znode(c, znode);
+				return -EINVAL;
+			}
+		}
+	}
+
+	if (extra) {
+		if (clean_cnt != atomic_long_read(&c->clean_zn_cnt)) {
+			ubifs_err("incorrect clean_zn_cnt %ld, calculated %ld",
+				  atomic_long_read(&c->clean_zn_cnt),
+				  clean_cnt);
+			return -EINVAL;
+		}
+		if (dirty_cnt != atomic_long_read(&c->dirty_zn_cnt)) {
+			ubifs_err("incorrect dirty_zn_cnt %ld, calculated %ld",
+				  atomic_long_read(&c->dirty_zn_cnt),
+				  dirty_cnt);
+			return -EINVAL;
+		}
+	}
+
+	return 0;
+}
+
+/**
+ * dbg_walk_index - walk the on-flash index.
+ * @c: UBIFS file-system description object
+ * @leaf_cb: called for each leaf node
+ * @znode_cb: called for each indexing node
+ * @priv: private date which is passed to callbacks
+ *
+ * This function walks the UBIFS index and calls the @leaf_cb for each leaf
+ * node and @znode_cb for each indexing node. Returns zero in case of success
+ * and a negative error code in case of failure.
+ *
+ * It would be better if this function removed every znode it pulled to into
+ * the TNC, so that the behavior more closely matched the non-debugging
+ * behavior.
+ */
+int dbg_walk_index(struct ubifs_info *c, dbg_leaf_callback leaf_cb,
+		   dbg_znode_callback znode_cb, void *priv)
+{
+	int err;
+	struct ubifs_zbranch *zbr;
+	struct ubifs_znode *znode, *child;
+
+	mutex_lock(&c->tnc_mutex);
+	/* If the root indexing node is not in TNC - pull it */
+	if (!c->zroot.znode) {
+		c->zroot.znode = ubifs_load_znode(c, &c->zroot, NULL, 0);
+		if (IS_ERR(c->zroot.znode)) {
+			err = PTR_ERR(c->zroot.znode);
+			c->zroot.znode = NULL;
+			goto out_unlock;
+		}
+	}
+
+	/*
+	 * We are going to traverse the indexing tree in the postorder manner.
+	 * Go down and find the leftmost indexing node where we are going to
+	 * start from.
+	 */
+	znode = c->zroot.znode;
+	while (znode->level > 0) {
+		zbr = &znode->zbranch[0];
+		child = zbr->znode;
+		if (!child) {
+			child = ubifs_load_znode(c, zbr, znode, 0);
+			if (IS_ERR(child)) {
+				err = PTR_ERR(child);
+				goto out_unlock;
+			}
+			zbr->znode = child;
+		}
+
+		znode = child;
+	}
+
+	/* Iterate over all indexing nodes */
+	while (1) {
+		int idx;
+
+		cond_resched();
+
+		if (znode_cb) {
+			err = znode_cb(c, znode, priv);
+			if (err) {
+				ubifs_err("znode checking function returned "
+					  "error %d", err);
+				dbg_dump_znode(c, znode);
+				goto out_dump;
+			}
+		}
+		if (leaf_cb && znode->level == 0) {
+			for (idx = 0; idx < znode->child_cnt; idx++) {
+				zbr = &znode->zbranch[idx];
+				err = leaf_cb(c, zbr, priv);
+				if (err) {
+					ubifs_err("leaf checking function "
+						  "returned error %d, for leaf "
+						  "at LEB %d:%d",
+						  err, zbr->lnum, zbr->offs);
+					goto out_dump;
+				}
+			}
+		}
+
+		if (!znode->parent)
+			break;
+
+		idx = znode->iip + 1;
+		znode = znode->parent;
+		if (idx < znode->child_cnt) {
+			/* Switch to the next index in the parent */
+			zbr = &znode->zbranch[idx];
+			child = zbr->znode;
+			if (!child) {
+				child = ubifs_load_znode(c, zbr, znode, idx);
+				if (IS_ERR(child)) {
+					err = PTR_ERR(child);
+					goto out_unlock;
+				}
+				zbr->znode = child;
+			}
+			znode = child;
+		} else
+			/*
+			 * This is the last child, switch to the parent and
+			 * continue.
+			 */
+			continue;
+
+		/* Go to the lowest leftmost znode in the new sub-tree */
+		while (znode->level > 0) {
+			zbr = &znode->zbranch[0];
+			child = zbr->znode;
+			if (!child) {
+				child = ubifs_load_znode(c, zbr, znode, 0);
+				if (IS_ERR(child)) {
+					err = PTR_ERR(child);
+					goto out_unlock;
+				}
+				zbr->znode = child;
+			}
+			znode = child;
+		}
+	}
+
+	mutex_unlock(&c->tnc_mutex);
+	return 0;
+
+out_dump:
+	if (znode->parent)
+		zbr = &znode->parent->zbranch[znode->iip];
+	else
+		zbr = &c->zroot;
+	ubifs_msg("dump of znode at LEB %d:%d", zbr->lnum, zbr->offs);
+	dbg_dump_znode(c, znode);
+out_unlock:
+	mutex_unlock(&c->tnc_mutex);
+	return err;
+}
+
+/**
+ * add_size - add znode size to partially calculated index size.
+ * @c: UBIFS file-system description object
+ * @znode: znode to add size for
+ * @priv: partially calculated index size
+ *
+ * This is a helper function for 'dbg_check_idx_size()' which is called for
+ * every indexing node and adds its size to the 'long long' variable pointed to
+ * by @priv.
+ */
+static int add_size(struct ubifs_info *c, struct ubifs_znode *znode, void *priv)
+{
+	long long *idx_size = priv;
+	int add;
+
+	add = ubifs_idx_node_sz(c, znode->child_cnt);
+	add = ALIGN(add, 8);
+	*idx_size += add;
+	return 0;
+}
+
+/**
+ * dbg_check_idx_size - check index size.
+ * @c: UBIFS file-system description object
+ * @idx_size: size to check
+ *
+ * This function walks the UBIFS index, calculates its size and checks that the
+ * size is equivalent to @idx_size. Returns zero in case of success and a
+ * negative error code in case of failure.
+ */
+int dbg_check_idx_size(struct ubifs_info *c, long long idx_size)
+{
+	int err;
+	long long calc = 0;
+
+	if (!(ubifs_chk_flags & UBIFS_CHK_IDX_SZ))
+		return 0;
+
+	err = dbg_walk_index(c, NULL, add_size, &calc);
+	if (err) {
+		ubifs_err("error %d while walking the index", err);
+		return err;
+	}
+
+	if (calc != idx_size) {
+		ubifs_err("index size check failed: calculated size is %lld, "
+			  "should be %lld", calc, idx_size);
+		dump_stack();
+		return -EINVAL;
+	}
+
+	return 0;
+}
+
+/**
+ * struct fsck_inode - information about an inode used when checking the file-system.
+ * @rb: link in the RB-tree of inodes
+ * @inum: inode number
+ * @mode: inode type, permissions, etc
+ * @nlink: inode link count
+ * @xattr_cnt: count of extended attributes
+ * @references: how many directory/xattr entries refer this inode (calculated
+ *              while walking the index)
+ * @calc_cnt: for directory inode count of child directories
+ * @size: inode size (read from on-flash inode)
+ * @xattr_sz: summary size of all extended attributes (read from on-flash
+ *            inode)
+ * @calc_sz: for directories calculated directory size
+ * @calc_xcnt: count of extended attributes
+ * @calc_xsz: calculated summary size of all extended attributes
+ * @xattr_nms: sum of lengths of all extended attribute names belonging to this
+ *             inode (read from on-flash inode)
+ * @calc_xnms: calculated sum of lengths of all extended attribute names
+ */
+struct fsck_inode {
+	struct rb_node rb;
+	ino_t inum;
+	umode_t mode;
+	unsigned int nlink;
+	unsigned int xattr_cnt;
+	int references;
+	int calc_cnt;
+	long long size;
+	unsigned int xattr_sz;
+	long long calc_sz;
+	long long calc_xcnt;
+	long long calc_xsz;
+	unsigned int xattr_nms;
+	long long calc_xnms;
+};
+
+/**
+ * struct fsck_data - private FS checking information.
+ * @inodes: RB-tree of all inodes (contains @struct fsck_inode objects)
+ */
+struct fsck_data {
+	struct rb_root inodes;
+};
+
+/**
+ * add_inode - add inode information to RB-tree of inodes.
+ * @c: UBIFS file-system description object
+ * @fsckd: FS checking information
+ * @ino: raw UBIFS inode to add
+ *
+ * This is a helper function for 'check_leaf()' which adds information about
+ * inode @ino to the RB-tree of inodes. Returns inode information pointer in
+ * case of success and a negative error code in case of failure.
+ */
+static struct fsck_inode *add_inode(struct ubifs_info *c,
+				    struct fsck_data *fsckd,
+				    struct ubifs_ino_node *ino)
+{
+	struct rb_node **p, *parent = NULL;
+	struct fsck_inode *fscki;
+	ino_t inum = key_inum_flash(c, &ino->key);
+
+	p = &fsckd->inodes.rb_node;
+	while (*p) {
+		parent = *p;
+		fscki = rb_entry(parent, struct fsck_inode, rb);
+		if (inum < fscki->inum)
+			p = &(*p)->rb_left;
+		else if (inum > fscki->inum)
+			p = &(*p)->rb_right;
+		else
+			return fscki;
+	}
+
+	if (inum > c->highest_inum) {
+		ubifs_err("too high inode number, max. is %lu",
+			  c->highest_inum);
+		return ERR_PTR(-EINVAL);
+	}
+
+	fscki = kzalloc(sizeof(struct fsck_inode), GFP_NOFS);
+	if (!fscki)
+		return ERR_PTR(-ENOMEM);
+
+	fscki->inum = inum;
+	fscki->nlink = le32_to_cpu(ino->nlink);
+	fscki->size = le64_to_cpu(ino->size);
+	fscki->xattr_cnt = le32_to_cpu(ino->xattr_cnt);
+	fscki->xattr_sz = le32_to_cpu(ino->xattr_size);
+	fscki->xattr_nms = le32_to_cpu(ino->xattr_names);
+	fscki->mode = le32_to_cpu(ino->mode);
+	if (S_ISDIR(fscki->mode)) {
+		fscki->calc_sz = UBIFS_INO_NODE_SZ;
+		fscki->calc_cnt = 2;
+	}
+	rb_link_node(&fscki->rb, parent, p);
+	rb_insert_color(&fscki->rb, &fsckd->inodes);
+	return fscki;
+}
+
+/**
+ * search_inode - search inode in the RB-tree of inodes.
+ * @fsckd: FS checking information
+ * @inum: inode number to search
+ *
+ * This is a helper function for 'check_leaf()' which searches inode @inum in
+ * the RB-tree of inodes and returns an inode information pointer or %NULL if
+ * the inode was not found.
+ */
+static struct fsck_inode *search_inode(struct fsck_data *fsckd, ino_t inum)
+{
+	struct rb_node *p;
+	struct fsck_inode *fscki;
+
+	p = fsckd->inodes.rb_node;
+	while (p) {
+		fscki = rb_entry(p, struct fsck_inode, rb);
+		if (inum < fscki->inum)
+			p = p->rb_left;
+		else if (inum > fscki->inum)
+			p = p->rb_right;
+		else
+			return fscki;
+	}
+	return NULL;
+}
+
+/**
+ * read_add_inode - read inode node and add it to RB-tree of inodes.
+ * @c: UBIFS file-system description object
+ * @fsckd: FS checking information
+ * @inum: inode number to read
+ *
+ * This is a helper function for 'check_leaf()' which finds inode node @inum in
+ * the index, reads it, and adds it to the RB-tree of inodes. Returns inode
+ * information pointer in case of success and a negative error code in case of
+ * failure.
+ */
+static struct fsck_inode *read_add_inode(struct ubifs_info *c,
+					 struct fsck_data *fsckd, ino_t inum)
+{
+	int n, err;
+	union ubifs_key key;
+	struct ubifs_znode *znode;
+	struct ubifs_zbranch *zbr;
+	struct ubifs_ino_node *ino;
+	struct fsck_inode *fscki;
+
+	fscki = search_inode(fsckd, inum);
+	if (fscki)
+		return fscki;
+
+	ino_key_init(c, &key, inum);
+	err = ubifs_lookup_level0(c, &key, &znode, &n);
+	if (!err) {
+		ubifs_err("inode %lu not found in index", inum);
+		return ERR_PTR(-ENOENT);
+	} else if (err < 0) {
+		ubifs_err("error %d while looking up inode %lu", err, inum);
+		return ERR_PTR(err);
+	}
+
+	zbr = &znode->zbranch[n];
+	if (zbr->len < UBIFS_INO_NODE_SZ) {
+		ubifs_err("bad node %lu node length %d", inum, zbr->len);
+		return ERR_PTR(-EINVAL);
+	}
+
+	ino = kmalloc(zbr->len, GFP_NOFS);
+	if (!ino)
+		return ERR_PTR(-ENOMEM);
+
+	err = ubifs_tnc_read_node(c, zbr, ino);
+	if (err) {
+		ubifs_err("cannot read inode node at LEB %d:%d, error %d",
+			  zbr->lnum, zbr->offs, err);
+		kfree(ino);
+		return ERR_PTR(err);
+	}
+
+	fscki = add_inode(c, fsckd, ino);
+	kfree(ino);
+	if (IS_ERR(fscki)) {
+		ubifs_err("error %ld while adding inode %lu node",
+			  PTR_ERR(fscki), inum);
+		return fscki;
+	}
+
+	return fscki;
+}
+
+/**
+ * check_leaf - check leaf node.
+ * @c: UBIFS file-system description object
+ * @zbr: zbranch of the leaf node to check
+ * @priv: FS checking information
+ *
+ * This is a helper function for 'dbg_check_filesystem()' which is called for
+ * every single leaf node while walking the indexing tree. It checks that the
+ * leaf node referred from the indexing tree exists, has correct CRC, and does
+ * some other basic validation. This function is also responsible for building
+ * an RB-tree of inodes - it adds all inodes into the RB-tree. It also
+ * calculates reference count, size, etc for each inode in order to later
+ * compare them to the information stored inside the inodes and detect possible
+ * inconsistencies. Returns zero in case of success and a negative error code
+ * in case of failure.
+ */
+static int check_leaf(struct ubifs_info *c, struct ubifs_zbranch *zbr,
+		      void *priv)
+{
+	ino_t inum;
+	void *node;
+	struct ubifs_ch *ch;
+	int err, type = key_type(c, &zbr->key);
+	struct fsck_inode *fscki;
+
+	if (zbr->len < UBIFS_CH_SZ) {
+		ubifs_err("bad leaf length %d (LEB %d:%d)",
+			  zbr->len, zbr->lnum, zbr->offs);
+		return -EINVAL;
+	}
+
+	node = kmalloc(zbr->len, GFP_NOFS);
+	if (!node)
+		return -ENOMEM;
+
+	err = ubifs_tnc_read_node(c, zbr, node);
+	if (err) {
+		ubifs_err("cannot read leaf node at LEB %d:%d, error %d",
+			  zbr->lnum, zbr->offs, err);
+		goto out_free;
+	}
+
+	/* If this is an inode node, add it to RB-tree of inodes */
+	if (type == UBIFS_INO_KEY) {
+		fscki = add_inode(c, priv, node);
+		if (IS_ERR(fscki)) {
+			err = PTR_ERR(fscki);
+			ubifs_err("error %d while adding inode node", err);
+			goto out_dump;
+		}
+		goto out;
+	}
+
+	if (type != UBIFS_DENT_KEY && type != UBIFS_XENT_KEY &&
+	    type != UBIFS_DATA_KEY) {
+		ubifs_err("unexpected node type %d at LEB %d:%d",
+			  type, zbr->lnum, zbr->offs);
+		err = -EINVAL;
+		goto out_free;
+	}
+
+	ch = node;
+	if (le64_to_cpu(ch->sqnum) > c->max_sqnum) {
+		ubifs_err("too high sequence number, max. is %llu",
+			  c->max_sqnum);
+		err = -EINVAL;
+		goto out_dump;
+	}
+
+	if (type == UBIFS_DATA_KEY) {
+		long long blk_offs;
+		struct ubifs_data_node *dn = node;
+
+		/*
+		 * Search the inode node this data node belongs to and insert
+		 * it to the RB-tree of inodes.
+		 */
+		inum = key_inum_flash(c, &dn->key);
+		fscki = read_add_inode(c, priv, inum);
+		if (IS_ERR(fscki)) {
+			err = PTR_ERR(fscki);
+			ubifs_err("error %d while processing data node and "
+				  "trying to find inode node %lu", err, inum);
+			goto out_dump;
+		}
+
+		/* Make sure the data node is within inode size */
+		blk_offs = key_block_flash(c, &dn->key);
+		blk_offs <<= UBIFS_BLOCK_SHIFT;
+		blk_offs += le32_to_cpu(dn->size);
+		if (blk_offs > fscki->size) {
+			ubifs_err("data node at LEB %d:%d is not within inode "
+				  "size %lld", zbr->lnum, zbr->offs,
+				  fscki->size);
+			err = -EINVAL;
+			goto out_dump;
+		}
+	} else {
+		int nlen;
+		struct ubifs_dent_node *dent = node;
+		struct fsck_inode *fscki1;
+
+		err = ubifs_validate_entry(c, dent);
+		if (err)
+			goto out_dump;
+
+		/*
+		 * Search the inode node this entry refers to and the parent
+		 * inode node and insert them to the RB-tree of inodes.
+		 */
+		inum = le64_to_cpu(dent->inum);
+		fscki = read_add_inode(c, priv, inum);
+		if (IS_ERR(fscki)) {
+			err = PTR_ERR(fscki);
+			ubifs_err("error %d while processing entry node and "
+				  "trying to find inode node %lu", err, inum);
+			goto out_dump;
+		}
+
+		/* Count how many direntries or xentries refers this inode */
+		fscki->references += 1;
+
+		inum = key_inum_flash(c, &dent->key);
+		fscki1 = read_add_inode(c, priv, inum);
+		if (IS_ERR(fscki1)) {
+			err = PTR_ERR(fscki);
+			ubifs_err("error %d while processing entry node and "
+				  "trying to find parent inode node %lu",
+				  err, inum);
+			goto out_dump;
+		}
+
+		nlen = le16_to_cpu(dent->nlen);
+		if (type == UBIFS_XENT_KEY) {
+			fscki1->calc_xcnt += 1;
+			fscki1->calc_xsz += CALC_DENT_SIZE(nlen);
+			fscki1->calc_xsz += CALC_XATTR_BYTES(fscki->size);
+			fscki1->calc_xnms += nlen;
+		} else {
+			fscki1->calc_sz += CALC_DENT_SIZE(nlen);
+			if (dent->type == UBIFS_ITYPE_DIR)
+				fscki1->calc_cnt += 1;
+		}
+	}
+
+out:
+	kfree(node);
+	return 0;
+
+out_dump:
+	ubifs_msg("dump of node at LEB %d:%d", zbr->lnum, zbr->offs);
+	dbg_dump_node(c, node);
+out_free:
+	kfree(node);
+	return err;
+}
+
+/**
+ * free_inodes - free RB-tree of inodes.
+ * @fsckd: FS checking information
+ */
+static void free_inodes(struct fsck_data *fsckd)
+{
+	struct rb_node *this = fsckd->inodes.rb_node;
+	struct fsck_inode *fscki;
+
+	while (this) {
+		if (this->rb_left)
+			this = this->rb_left;
+		else if (this->rb_right)
+			this = this->rb_right;
+		else {
+			fscki = rb_entry(this, struct fsck_inode, rb);
+			this = rb_parent(this);
+			if (this) {
+				if (this->rb_left == &fscki->rb)
+					this->rb_left = NULL;
+				else
+					this->rb_right = NULL;
+			}
+			kfree(fscki);
+		}
+	}
+}
+
+/**
+ * check_inodes - checks all inodes.
+ * @c: UBIFS file-system description object
+ * @fsckd: FS checking information
+ *
+ * This is a helper function for 'dbg_check_filesystem()' which walks the
+ * RB-tree of inodes after the index scan has been finished, and checks that
+ * inode nlink, size, etc are correct. Returns zero if inodes are fine,
+ * %-EINVAL if not, and a negative error code in case of failure.
+ */
+static int check_inodes(struct ubifs_info *c, struct fsck_data *fsckd)
+{
+	int n, err;
+	union ubifs_key key;
+	struct ubifs_znode *znode;
+	struct ubifs_zbranch *zbr;
+	struct ubifs_ino_node *ino;
+	struct fsck_inode *fscki;
+	struct rb_node *this = rb_first(&fsckd->inodes);
+
+	while (this) {
+		fscki = rb_entry(this, struct fsck_inode, rb);
+		this = rb_next(this);
+
+		if (S_ISDIR(fscki->mode)) {
+			/*
+			 * Directories have to have exactly one reference (they
+			 * cannot have hardlinks), although root inode is an
+			 * exception.
+			 */
+			if (fscki->inum != UBIFS_ROOT_INO &&
+			    fscki->references != 1) {
+				ubifs_err("directory inode %lu has %d "
+					  "direntries which refer it, but "
+					  "should be 1", fscki->inum,
+					  fscki->references);
+				goto out_dump;
+			}
+			if (fscki->inum == UBIFS_ROOT_INO &&
+			    fscki->references != 0) {
+				ubifs_err("root inode %lu has non-zero (%d) "
+					  "direntries which refer it",
+					  fscki->inum, fscki->references);
+				goto out_dump;
+			}
+			if (fscki->calc_sz != fscki->size) {
+				ubifs_err("directory inode %lu size is %lld, "
+					  "but calculated size is %lld",
+					  fscki->inum, fscki->size,
+					  fscki->calc_sz);
+				goto out_dump;
+			}
+			if (fscki->calc_cnt != fscki->nlink) {
+				ubifs_err("directory inode %lu nlink is %d, "
+					  "but calculated nlink is %d",
+					  fscki->inum, fscki->nlink,
+					  fscki->calc_cnt);
+				goto out_dump;
+			}
+		} else {
+			if (fscki->references != fscki->nlink) {
+				ubifs_err("inode %lu nlink is %d, but "
+					  "calculated nlink is %d", fscki->inum,
+					  fscki->nlink, fscki->references);
+				goto out_dump;
+			}
+		}
+		if (fscki->xattr_sz != fscki->calc_xsz) {
+			ubifs_err("inode %lu has xattr size %u, but "
+				  "calculated size is %lld",
+				  fscki->inum, fscki->xattr_sz,
+				  fscki->calc_xsz);
+			goto out_dump;
+		}
+		if (fscki->xattr_cnt != fscki->calc_xcnt) {
+			ubifs_err("inode %lu has %u xattrs, but "
+				  "calculated count is %lld", fscki->inum,
+				  fscki->xattr_cnt, fscki->calc_xcnt);
+			goto out_dump;
+		}
+		if (fscki->xattr_nms != fscki->calc_xnms) {
+			ubifs_err("inode %lu has xattr names' size %u, but "
+				  "calculated names' size is %lld",
+				  fscki->inum, fscki->xattr_nms,
+				  fscki->calc_xnms);
+			goto out_dump;
+		}
+	}
+
+	return 0;
+
+out_dump:
+	/* Read the bad inode and dump it */
+	ino_key_init(c, &key, fscki->inum);
+	err = ubifs_lookup_level0(c, &key, &znode, &n);
+	if (!err) {
+		ubifs_err("inode %lu not found in index", fscki->inum);
+		return -ENOENT;
+	} else if (err < 0) {
+		ubifs_err("error %d while looking up inode %lu",
+			  err, fscki->inum);
+		return err;
+	}
+
+	zbr = &znode->zbranch[n];
+	ino = kmalloc(zbr->len, GFP_NOFS);
+	if (!ino)
+		return -ENOMEM;
+
+	err = ubifs_tnc_read_node(c, zbr, ino);
+	if (err) {
+		ubifs_err("cannot read inode node at LEB %d:%d, error %d",
+			  zbr->lnum, zbr->offs, err);
+		kfree(ino);
+		return err;
+	}
+
+	ubifs_msg("dump of the inode %lu sitting in LEB %d:%d",
+		  fscki->inum, zbr->lnum, zbr->offs);
+	dbg_dump_node(c, ino);
+	kfree(ino);
+	return -EINVAL;
+}
+
+/**
+ * dbg_check_filesystem - check the file-system.
+ * @c: UBIFS file-system description object
+ *
+ * This function checks the file system, namely:
+ * o makes sure that all leaf nodes exist and their CRCs are correct;
+ * o makes sure inode nlink, size, xattr size/count are correct (for all
+ *   inodes).
+ *
+ * The function reads whole indexing tree and all nodes, so it is pretty
+ * heavy-weight. Returns zero if the file-system is consistent, %-EINVAL if
+ * not, and a negative error code in case of failure.
+ */
+int dbg_check_filesystem(struct ubifs_info *c)
+{
+	int err;
+	struct fsck_data fsckd;
+
+	if (!(ubifs_chk_flags & UBIFS_CHK_FS))
+		return 0;
+
+	fsckd.inodes = RB_ROOT;
+	err = dbg_walk_index(c, check_leaf, NULL, &fsckd);
+	if (err)
+		goto out_free;
+
+	err = check_inodes(c, &fsckd);
+	if (err)
+		goto out_free;
+
+	free_inodes(&fsckd);
+	return 0;
+
+out_free:
+	ubifs_err("file-system check failed with error %d", err);
+	dump_stack();
+	free_inodes(&fsckd);
+	return err;
+}
+
+static int invocation_cnt;
+
+int dbg_force_in_the_gaps(void)
+{
+	if (!dbg_force_in_the_gaps_enabled)
+		return 0;
+	/* Force in-the-gaps every 8th commit */
+	return !((invocation_cnt++) & 0x7);
+}
+
+/* Failure mode for recovery testing */
+
+#define chance(n, d) (simple_rand() <= (n) * 32768LL / (d))
+
+struct failure_mode_info {
+	struct list_head list;
+	struct ubifs_info *c;
+};
+
+static LIST_HEAD(fmi_list);
+static DEFINE_SPINLOCK(fmi_lock);
+
+static unsigned int next;
+
+static int simple_rand(void)
+{
+	if (next == 0)
+		next = current->pid;
+	next = next * 1103515245 + 12345;
+	return (next >> 16) & 32767;
+}
+
+void dbg_failure_mode_registration(struct ubifs_info *c)
+{
+	struct failure_mode_info *fmi;
+
+	fmi = kmalloc(sizeof(struct failure_mode_info), GFP_NOFS);
+	if (!fmi) {
+		dbg_err("Failed to register failure mode - no memory");
+		return;
+	}
+	fmi->c = c;
+	spin_lock(&fmi_lock);
+	list_add_tail(&fmi->list, &fmi_list);
+	spin_unlock(&fmi_lock);
+}
+
+void dbg_failure_mode_deregistration(struct ubifs_info *c)
+{
+	struct failure_mode_info *fmi, *tmp;
+
+	spin_lock(&fmi_lock);
+	list_for_each_entry_safe(fmi, tmp, &fmi_list, list)
+		if (fmi->c == c) {
+			list_del(&fmi->list);
+			kfree(fmi);
+		}
+	spin_unlock(&fmi_lock);
+}
+
+static struct ubifs_info *dbg_find_info(struct ubi_volume_desc *desc)
+{
+	struct failure_mode_info *fmi;
+
+	spin_lock(&fmi_lock);
+	list_for_each_entry(fmi, &fmi_list, list)
+		if (fmi->c->ubi == desc) {
+			struct ubifs_info *c = fmi->c;
+
+			spin_unlock(&fmi_lock);
+			return c;
+		}
+	spin_unlock(&fmi_lock);
+	return NULL;
+}
+
+static int in_failure_mode(struct ubi_volume_desc *desc)
+{
+	struct ubifs_info *c = dbg_find_info(desc);
+
+	if (c && dbg_failure_mode)
+		return c->failure_mode;
+	return 0;
+}
+
+static int do_fail(struct ubi_volume_desc *desc, int lnum, int write)
+{
+	struct ubifs_info *c = dbg_find_info(desc);
+
+	if (!c || !dbg_failure_mode)
+		return 0;
+	if (c->failure_mode)
+		return 1;
+	if (!c->fail_cnt) {
+		/* First call - decide delay to failure */
+		if (chance(1, 2)) {
+			unsigned int delay = 1 << (simple_rand() >> 11);
+
+			if (chance(1, 2)) {
+				c->fail_delay = 1;
+				c->fail_timeout = jiffies +
+						  msecs_to_jiffies(delay);
+				dbg_rcvry("failing after %ums", delay);
+			} else {
+				c->fail_delay = 2;
+				c->fail_cnt_max = delay;
+				dbg_rcvry("failing after %u calls", delay);
+			}
+		}
+		c->fail_cnt += 1;
+	}
+	/* Determine if failure delay has expired */
+	if (c->fail_delay == 1) {
+		if (time_before(jiffies, c->fail_timeout))
+			return 0;
+	} else if (c->fail_delay == 2)
+		if (c->fail_cnt++ < c->fail_cnt_max)
+			return 0;
+	if (lnum == UBIFS_SB_LNUM) {
+		if (write) {
+			if (chance(1, 2))
+				return 0;
+		} else if (chance(19, 20))
+			return 0;
+		dbg_rcvry("failing in super block LEB %d", lnum);
+	} else if (lnum == UBIFS_MST_LNUM || lnum == UBIFS_MST_LNUM + 1) {
+		if (chance(19, 20))
+			return 0;
+		dbg_rcvry("failing in master LEB %d", lnum);
+	} else if (lnum >= UBIFS_LOG_LNUM && lnum <= c->log_last) {
+		if (write) {
+			if (chance(99, 100))
+				return 0;
+		} else if (chance(399, 400))
+			return 0;
+		dbg_rcvry("failing in log LEB %d", lnum);
+	} else if (lnum >= c->lpt_first && lnum <= c->lpt_last) {
+		if (write) {
+			if (chance(7, 8))
+				return 0;
+		} else if (chance(19, 20))
+			return 0;
+		dbg_rcvry("failing in LPT LEB %d", lnum);
+	} else if (lnum >= c->orph_first && lnum <= c->orph_last) {
+		if (write) {
+			if (chance(1, 2))
+				return 0;
+		} else if (chance(9, 10))
+			return 0;
+		dbg_rcvry("failing in orphan LEB %d", lnum);
+	} else if (lnum == c->ihead_lnum) {
+		if (chance(99, 100))
+			return 0;
+		dbg_rcvry("failing in index head LEB %d", lnum);
+	} else if (c->jheads && lnum == c->jheads[GCHD].wbuf.lnum) {
+		if (chance(9, 10))
+			return 0;
+		dbg_rcvry("failing in GC head LEB %d", lnum);
+	} else if (write && !RB_EMPTY_ROOT(&c->buds) &&
+		   !ubifs_search_bud(c, lnum)) {
+		if (chance(19, 20))
+			return 0;
+		dbg_rcvry("failing in non-bud LEB %d", lnum);
+	} else if (c->cmt_state == COMMIT_RUNNING_BACKGROUND ||
+		   c->cmt_state == COMMIT_RUNNING_REQUIRED) {
+		if (chance(999, 1000))
+			return 0;
+		dbg_rcvry("failing in bud LEB %d commit running", lnum);
+	} else {
+		if (chance(9999, 10000))
+			return 0;
+		dbg_rcvry("failing in bud LEB %d commit not running", lnum);
+	}
+	ubifs_err("*** SETTING FAILURE MODE ON (LEB %d) ***", lnum);
+	c->failure_mode = 1;
+	dump_stack();
+	return 1;
+}
+
+static void cut_data(const void *buf, int len)
+{
+	int flen, i;
+	unsigned char *p = (void *)buf;
+
+	flen = (len * (long long)simple_rand()) >> 15;
+	for (i = flen; i < len; i++)
+		p[i] = 0xff;
+}
+
+int dbg_leb_read(struct ubi_volume_desc *desc, int lnum, char *buf, int offset,
+		 int len, int check)
+{
+	if (in_failure_mode(desc))
+		return -EIO;
+	return ubi_leb_read(desc, lnum, buf, offset, len, check);
+}
+
+int dbg_leb_write(struct ubi_volume_desc *desc, int lnum, const void *buf,
+		  int offset, int len, int dtype)
+{
+	int err;
+
+	if (in_failure_mode(desc))
+		return -EIO;
+	if (do_fail(desc, lnum, 1))
+		cut_data(buf, len);
+	err = ubi_leb_write(desc, lnum, buf, offset, len, dtype);
+	if (err)
+		return err;
+	if (in_failure_mode(desc))
+		return -EIO;
+	return 0;
+}
+
+int dbg_leb_change(struct ubi_volume_desc *desc, int lnum, const void *buf,
+		   int len, int dtype)
+{
+	int err;
+
+	if (do_fail(desc, lnum, 1))
+		return -EIO;
+	err = ubi_leb_change(desc, lnum, buf, len, dtype);
+	if (err)
+		return err;
+	if (do_fail(desc, lnum, 1))
+		return -EIO;
+	return 0;
+}
+
+int dbg_leb_erase(struct ubi_volume_desc *desc, int lnum)
+{
+	int err;
+
+	if (do_fail(desc, lnum, 0))
+		return -EIO;
+	err = ubi_leb_erase(desc, lnum);
+	if (err)
+		return err;
+	if (do_fail(desc, lnum, 0))
+		return -EIO;
+	return 0;
+}
+
+int dbg_leb_unmap(struct ubi_volume_desc *desc, int lnum)
+{
+	int err;
+
+	if (do_fail(desc, lnum, 0))
+		return -EIO;
+	err = ubi_leb_unmap(desc, lnum);
+	if (err)
+		return err;
+	if (do_fail(desc, lnum, 0))
+		return -EIO;
+	return 0;
+}
+
+int dbg_is_mapped(struct ubi_volume_desc *desc, int lnum)
+{
+	if (in_failure_mode(desc))
+		return -EIO;
+	return ubi_is_mapped(desc, lnum);
+}
+
+int dbg_leb_map(struct ubi_volume_desc *desc, int lnum, int dtype)
+{
+	int err;
+
+	if (do_fail(desc, lnum, 0))
+		return -EIO;
+	err = ubi_leb_map(desc, lnum, dtype);
+	if (err)
+		return err;
+	if (do_fail(desc, lnum, 0))
+		return -EIO;
+	return 0;
+}
+
+#endif /* CONFIG_UBIFS_FS_DEBUG */
diff --git a/fs/ubifs/debug.h b/fs/ubifs/debug.h
new file mode 100644
index 00000000000..3c4f1e93c9e
--- /dev/null
+++ b/fs/ubifs/debug.h
@@ -0,0 +1,403 @@
+/*
+ * This file is part of UBIFS.
+ *
+ * Copyright (C) 2006-2008 Nokia Corporation.
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 as published by
+ * the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
+ * more details.
+ *
+ * You should have received a copy of the GNU General Public License along with
+ * this program; if not, write to the Free Software Foundation, Inc., 51
+ * Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
+ *
+ * Authors: Artem Bityutskiy (Битюцкий Артём)
+ *          Adrian Hunter
+ */
+
+#ifndef __UBIFS_DEBUG_H__
+#define __UBIFS_DEBUG_H__
+
+#ifdef CONFIG_UBIFS_FS_DEBUG
+
+#define UBIFS_DBG(op) op
+
+#define ubifs_assert(expr)  do {                                               \
+	if (unlikely(!(expr))) {                                               \
+		printk(KERN_CRIT "UBIFS assert failed in %s at %u (pid %d)\n", \
+		       __func__, __LINE__, current->pid);                      \
+		dbg_dump_stack();                                              \
+	}                                                                      \
+} while (0)
+
+#define ubifs_assert_cmt_locked(c) do {                                        \
+	if (unlikely(down_write_trylock(&(c)->commit_sem))) {                  \
+		up_write(&(c)->commit_sem);                                    \
+		printk(KERN_CRIT "commit lock is not locked!\n");              \
+		ubifs_assert(0);                                               \
+	}                                                                      \
+} while (0)
+
+#define dbg_dump_stack() do {                                                  \
+	if (!dbg_failure_mode)                                                 \
+		dump_stack();                                                  \
+} while (0)
+
+/* Generic debugging messages */
+#define dbg_msg(fmt, ...) do {                                                 \
+	spin_lock(&dbg_lock);                                                  \
+	printk(KERN_DEBUG "UBIFS DBG (pid %d): %s: " fmt "\n", current->pid,   \
+	       __func__, ##__VA_ARGS__);                                       \
+	spin_unlock(&dbg_lock);                                                \
+} while (0)
+
+#define dbg_do_msg(typ, fmt, ...) do {                                         \
+	if (ubifs_msg_flags & typ)                                             \
+		dbg_msg(fmt, ##__VA_ARGS__);                                   \
+} while (0)
+
+#define dbg_err(fmt, ...) do {                                                 \
+	spin_lock(&dbg_lock);                                                  \
+	ubifs_err(fmt, ##__VA_ARGS__);                                         \
+	spin_unlock(&dbg_lock);                                                \
+} while (0)
+
+const char *dbg_key_str0(const struct ubifs_info *c,
+			 const union ubifs_key *key);
+const char *dbg_key_str1(const struct ubifs_info *c,
+			 const union ubifs_key *key);
+
+/*
+ * DBGKEY macros require dbg_lock to be held, which it is in the dbg message
+ * macros.
+ */
+#define DBGKEY(key) dbg_key_str0(c, (key))
+#define DBGKEY1(key) dbg_key_str1(c, (key))
+
+/* General messages */
+#define dbg_gen(fmt, ...)        dbg_do_msg(UBIFS_MSG_GEN, fmt, ##__VA_ARGS__)
+
+/* Additional journal messages */
+#define dbg_jnl(fmt, ...)        dbg_do_msg(UBIFS_MSG_JNL, fmt, ##__VA_ARGS__)
+
+/* Additional TNC messages */
+#define dbg_tnc(fmt, ...)        dbg_do_msg(UBIFS_MSG_TNC, fmt, ##__VA_ARGS__)
+
+/* Additional lprops messages */
+#define dbg_lp(fmt, ...)         dbg_do_msg(UBIFS_MSG_LP, fmt, ##__VA_ARGS__)
+
+/* Additional LEB find messages */
+#define dbg_find(fmt, ...)       dbg_do_msg(UBIFS_MSG_FIND, fmt, ##__VA_ARGS__)
+
+/* Additional mount messages */
+#define dbg_mnt(fmt, ...)        dbg_do_msg(UBIFS_MSG_MNT, fmt, ##__VA_ARGS__)
+
+/* Additional I/O messages */
+#define dbg_io(fmt, ...)         dbg_do_msg(UBIFS_MSG_IO, fmt, ##__VA_ARGS__)
+
+/* Additional commit messages */
+#define dbg_cmt(fmt, ...)        dbg_do_msg(UBIFS_MSG_CMT, fmt, ##__VA_ARGS__)
+
+/* Additional budgeting messages */
+#define dbg_budg(fmt, ...)       dbg_do_msg(UBIFS_MSG_BUDG, fmt, ##__VA_ARGS__)
+
+/* Additional log messages */
+#define dbg_log(fmt, ...)        dbg_do_msg(UBIFS_MSG_LOG, fmt, ##__VA_ARGS__)
+
+/* Additional gc messages */
+#define dbg_gc(fmt, ...)         dbg_do_msg(UBIFS_MSG_GC, fmt, ##__VA_ARGS__)
+
+/* Additional scan messages */
+#define dbg_scan(fmt, ...)       dbg_do_msg(UBIFS_MSG_SCAN, fmt, ##__VA_ARGS__)
+
+/* Additional recovery messages */
+#define dbg_rcvry(fmt, ...)      dbg_do_msg(UBIFS_MSG_RCVRY, fmt, ##__VA_ARGS__)
+
+/*
+ * Debugging message type flags (must match msg_type_names in debug.c).
+ *
+ * UBIFS_MSG_GEN: general messages
+ * UBIFS_MSG_JNL: journal messages
+ * UBIFS_MSG_MNT: mount messages
+ * UBIFS_MSG_CMT: commit messages
+ * UBIFS_MSG_FIND: LEB find messages
+ * UBIFS_MSG_BUDG: budgeting messages
+ * UBIFS_MSG_GC: garbage collection messages
+ * UBIFS_MSG_TNC: TNC messages
+ * UBIFS_MSG_LP: lprops messages
+ * UBIFS_MSG_IO: I/O messages
+ * UBIFS_MSG_LOG: log messages
+ * UBIFS_MSG_SCAN: scan messages
+ * UBIFS_MSG_RCVRY: recovery messages
+ */
+enum {
+	UBIFS_MSG_GEN   = 0x1,
+	UBIFS_MSG_JNL   = 0x2,
+	UBIFS_MSG_MNT   = 0x4,
+	UBIFS_MSG_CMT   = 0x8,
+	UBIFS_MSG_FIND  = 0x10,
+	UBIFS_MSG_BUDG  = 0x20,
+	UBIFS_MSG_GC    = 0x40,
+	UBIFS_MSG_TNC   = 0x80,
+	UBIFS_MSG_LP    = 0x100,
+	UBIFS_MSG_IO    = 0x200,
+	UBIFS_MSG_LOG   = 0x400,
+	UBIFS_MSG_SCAN  = 0x800,
+	UBIFS_MSG_RCVRY = 0x1000,
+};
+
+/* Debugging message type flags for each default debug message level */
+#define UBIFS_MSG_LVL_0 0
+#define UBIFS_MSG_LVL_1 0x1
+#define UBIFS_MSG_LVL_2 0x7f
+#define UBIFS_MSG_LVL_3 0xffff
+
+/*
+ * Debugging check flags (must match chk_names in debug.c).
+ *
+ * UBIFS_CHK_GEN: general checks
+ * UBIFS_CHK_TNC: check TNC
+ * UBIFS_CHK_IDX_SZ: check index size
+ * UBIFS_CHK_ORPH: check orphans
+ * UBIFS_CHK_OLD_IDX: check the old index
+ * UBIFS_CHK_LPROPS: check lprops
+ * UBIFS_CHK_FS: check the file-system
+ */
+enum {
+	UBIFS_CHK_GEN     = 0x1,
+	UBIFS_CHK_TNC     = 0x2,
+	UBIFS_CHK_IDX_SZ  = 0x4,
+	UBIFS_CHK_ORPH    = 0x8,
+	UBIFS_CHK_OLD_IDX = 0x10,
+	UBIFS_CHK_LPROPS  = 0x20,
+	UBIFS_CHK_FS      = 0x40,
+};
+
+/*
+ * Special testing flags (must match tst_names in debug.c).
+ *
+ * UBIFS_TST_FORCE_IN_THE_GAPS: force the use of in-the-gaps method
+ * UBIFS_TST_RCVRY: failure mode for recovery testing
+ */
+enum {
+	UBIFS_TST_FORCE_IN_THE_GAPS = 0x2,
+	UBIFS_TST_RCVRY             = 0x4,
+};
+
+#if CONFIG_UBIFS_FS_DEBUG_MSG_LVL == 1
+#define UBIFS_MSG_FLAGS_DEFAULT UBIFS_MSG_LVL_1
+#elif CONFIG_UBIFS_FS_DEBUG_MSG_LVL == 2
+#define UBIFS_MSG_FLAGS_DEFAULT UBIFS_MSG_LVL_2
+#elif CONFIG_UBIFS_FS_DEBUG_MSG_LVL == 3
+#define UBIFS_MSG_FLAGS_DEFAULT UBIFS_MSG_LVL_3
+#else
+#define UBIFS_MSG_FLAGS_DEFAULT UBIFS_MSG_LVL_0
+#endif
+
+#ifdef CONFIG_UBIFS_FS_DEBUG_CHKS
+#define UBIFS_CHK_FLAGS_DEFAULT 0xffffffff
+#else
+#define UBIFS_CHK_FLAGS_DEFAULT 0
+#endif
+
+extern spinlock_t dbg_lock;
+
+extern unsigned int ubifs_msg_flags;
+extern unsigned int ubifs_chk_flags;
+extern unsigned int ubifs_tst_flags;
+
+/* Dump functions */
+
+const char *dbg_ntype(int type);
+const char *dbg_cstate(int cmt_state);
+const char *dbg_get_key_dump(const struct ubifs_info *c,
+			     const union ubifs_key *key);
+void dbg_dump_inode(const struct ubifs_info *c, const struct inode *inode);
+void dbg_dump_node(const struct ubifs_info *c, const void *node);
+void dbg_dump_budget_req(const struct ubifs_budget_req *req);
+void dbg_dump_lstats(const struct ubifs_lp_stats *lst);
+void dbg_dump_budg(struct ubifs_info *c);
+void dbg_dump_lprop(const struct ubifs_info *c, const struct ubifs_lprops *lp);
+void dbg_dump_lprops(struct ubifs_info *c);
+void dbg_dump_leb(const struct ubifs_info *c, int lnum);
+void dbg_dump_znode(const struct ubifs_info *c,
+		    const struct ubifs_znode *znode);
+void dbg_dump_heap(struct ubifs_info *c, struct ubifs_lpt_heap *heap, int cat);
+void dbg_dump_pnode(struct ubifs_info *c, struct ubifs_pnode *pnode,
+		    struct ubifs_nnode *parent, int iip);
+void dbg_dump_tnc(struct ubifs_info *c);
+void dbg_dump_index(struct ubifs_info *c);
+
+/* Checking helper functions */
+
+typedef int (*dbg_leaf_callback)(struct ubifs_info *c,
+				 struct ubifs_zbranch *zbr, void *priv);
+typedef int (*dbg_znode_callback)(struct ubifs_info *c,
+				  struct ubifs_znode *znode, void *priv);
+
+int dbg_walk_index(struct ubifs_info *c, dbg_leaf_callback leaf_cb,
+		   dbg_znode_callback znode_cb, void *priv);
+
+/* Checking functions */
+
+int dbg_check_lprops(struct ubifs_info *c);
+
+int dbg_old_index_check_init(struct ubifs_info *c, struct ubifs_zbranch *zroot);
+int dbg_check_old_index(struct ubifs_info *c, struct ubifs_zbranch *zroot);
+
+int dbg_check_cats(struct ubifs_info *c);
+
+int dbg_check_ltab(struct ubifs_info *c);
+
+int dbg_check_synced_i_size(struct inode *inode);
+
+int dbg_check_dir_size(struct ubifs_info *c, const struct inode *dir);
+
+int dbg_check_tnc(struct ubifs_info *c, int extra);
+
+int dbg_check_idx_size(struct ubifs_info *c, long long idx_size);
+
+int dbg_check_filesystem(struct ubifs_info *c);
+
+void dbg_check_heap(struct ubifs_info *c, struct ubifs_lpt_heap *heap, int cat,
+		    int add_pos);
+
+int dbg_check_lprops(struct ubifs_info *c);
+int dbg_check_lpt_nodes(struct ubifs_info *c, struct ubifs_cnode *cnode,
+			int row, int col);
+
+/* Force the use of in-the-gaps method for testing */
+
+#define dbg_force_in_the_gaps_enabled \
+	(ubifs_tst_flags & UBIFS_TST_FORCE_IN_THE_GAPS)
+
+int dbg_force_in_the_gaps(void);
+
+/* Failure mode for recovery testing */
+
+#define dbg_failure_mode (ubifs_tst_flags & UBIFS_TST_RCVRY)
+
+void dbg_failure_mode_registration(struct ubifs_info *c);
+void dbg_failure_mode_deregistration(struct ubifs_info *c);
+
+#ifndef UBIFS_DBG_PRESERVE_UBI
+
+#define ubi_leb_read   dbg_leb_read
+#define ubi_leb_write  dbg_leb_write
+#define ubi_leb_change dbg_leb_change
+#define ubi_leb_erase  dbg_leb_erase
+#define ubi_leb_unmap  dbg_leb_unmap
+#define ubi_is_mapped  dbg_is_mapped
+#define ubi_leb_map    dbg_leb_map
+
+#endif
+
+int dbg_leb_read(struct ubi_volume_desc *desc, int lnum, char *buf, int offset,
+		 int len, int check);
+int dbg_leb_write(struct ubi_volume_desc *desc, int lnum, const void *buf,
+		  int offset, int len, int dtype);
+int dbg_leb_change(struct ubi_volume_desc *desc, int lnum, const void *buf,
+		   int len, int dtype);
+int dbg_leb_erase(struct ubi_volume_desc *desc, int lnum);
+int dbg_leb_unmap(struct ubi_volume_desc *desc, int lnum);
+int dbg_is_mapped(struct ubi_volume_desc *desc, int lnum);
+int dbg_leb_map(struct ubi_volume_desc *desc, int lnum, int dtype);
+
+static inline int dbg_read(struct ubi_volume_desc *desc, int lnum, char *buf,
+			   int offset, int len)
+{
+	return dbg_leb_read(desc, lnum, buf, offset, len, 0);
+}
+
+static inline int dbg_write(struct ubi_volume_desc *desc, int lnum,
+			    const void *buf, int offset, int len)
+{
+	return dbg_leb_write(desc, lnum, buf, offset, len, UBI_UNKNOWN);
+}
+
+static inline int dbg_change(struct ubi_volume_desc *desc, int lnum,
+				    const void *buf, int len)
+{
+	return dbg_leb_change(desc, lnum, buf, len, UBI_UNKNOWN);
+}
+
+#else /* !CONFIG_UBIFS_FS_DEBUG */
+
+#define UBIFS_DBG(op)
+#define ubifs_assert(expr)                         ({})
+#define ubifs_assert_cmt_locked(c)
+#define dbg_dump_stack()
+#define dbg_err(fmt, ...)                          ({})
+#define dbg_msg(fmt, ...)                          ({})
+#define dbg_key(c, key, fmt, ...)                  ({})
+
+#define dbg_gen(fmt, ...)                          ({})
+#define dbg_jnl(fmt, ...)                          ({})
+#define dbg_tnc(fmt, ...)                          ({})
+#define dbg_lp(fmt, ...)                           ({})
+#define dbg_find(fmt, ...)                         ({})
+#define dbg_mnt(fmt, ...)                          ({})
+#define dbg_io(fmt, ...)                           ({})
+#define dbg_cmt(fmt, ...)                          ({})
+#define dbg_budg(fmt, ...)                         ({})
+#define dbg_log(fmt, ...)                          ({})
+#define dbg_gc(fmt, ...)                           ({})
+#define dbg_scan(fmt, ...)                         ({})
+#define dbg_rcvry(fmt, ...)                        ({})
+
+#define dbg_ntype(type)                            ""
+#define dbg_cstate(cmt_state)                      ""
+#define dbg_get_key_dump(c, key)                   ({})
+#define dbg_dump_inode(c, inode)                   ({})
+#define dbg_dump_node(c, node)                     ({})
+#define dbg_dump_budget_req(req)                   ({})
+#define dbg_dump_lstats(lst)                       ({})
+#define dbg_dump_budg(c)                           ({})
+#define dbg_dump_lprop(c, lp)                      ({})
+#define dbg_dump_lprops(c)                         ({})
+#define dbg_dump_leb(c, lnum)                      ({})
+#define dbg_dump_znode(c, znode)                   ({})
+#define dbg_dump_heap(c, heap, cat)                ({})
+#define dbg_dump_pnode(c, pnode, parent, iip)      ({})
+#define dbg_dump_tnc(c)                            ({})
+#define dbg_dump_index(c)                          ({})
+
+#define dbg_walk_index(c, leaf_cb, znode_cb, priv) 0
+
+#define dbg_old_index_check_init(c, zroot)         0
+#define dbg_check_old_index(c, zroot)              0
+
+#define dbg_check_cats(c)                          0
+
+#define dbg_check_ltab(c)                          0
+
+#define dbg_check_synced_i_size(inode)             0
+
+#define dbg_check_dir_size(c, dir)                 0
+
+#define dbg_check_tnc(c, x)                        0
+
+#define dbg_check_idx_size(c, idx_size)            0
+
+#define dbg_check_filesystem(c)                    0
+
+#define dbg_check_heap(c, heap, cat, add_pos)      ({})
+
+#define dbg_check_lprops(c)                        0
+#define dbg_check_lpt_nodes(c, cnode, row, col)    0
+
+#define dbg_force_in_the_gaps_enabled              0
+#define dbg_force_in_the_gaps()                    0
+
+#define dbg_failure_mode                           0
+#define dbg_failure_mode_registration(c)           ({})
+#define dbg_failure_mode_deregistration(c)         ({})
+
+#endif /* !CONFIG_UBIFS_FS_DEBUG */
+
+#endif /* !__UBIFS_DEBUG_H__ */
diff --git a/fs/ubifs/dir.c b/fs/ubifs/dir.c
new file mode 100644
index 00000000000..e90374be7d3
--- /dev/null
+++ b/fs/ubifs/dir.c
@@ -0,0 +1,1240 @@
+/* * This file is part of UBIFS.
+ *
+ * Copyright (C) 2006-2008 Nokia Corporation.
+ * Copyright (C) 2006, 2007 University of Szeged, Hungary
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 as published by
+ * the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
+ * more details.
+ *
+ * You should have received a copy of the GNU General Public License along with
+ * this program; if not, write to the Free Software Foundation, Inc., 51
+ * Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
+ *
+ * Authors: Artem Bityutskiy (Битюцкий Артём)
+ *          Adrian Hunter
+ *          Zoltan Sogor
+ */
+
+/*
+ * This file implements directory operations.
+ *
+ * All FS operations in this file allocate budget before writing anything to the
+ * media. If they fail to allocate it, the error is returned. The only
+ * exceptions are 'ubifs_unlink()' and 'ubifs_rmdir()' which keep working even
+ * if they unable to allocate the budget, because deletion %-ENOSPC failure is
+ * not what users are usually ready to get. UBIFS budgeting subsystem has some
+ * space reserved for these purposes.
+ *
+ * All operations in this file write all inodes which they change straight
+ * away, instead of marking them dirty. For example, 'ubifs_link()' changes
+ * @i_size of the parent inode and writes the parent inode together with the
+ * target inode. This was done to simplify file-system recovery which would
+ * otherwise be very difficult to do. The only exception is rename which marks
+ * the re-named inode dirty (because its @i_ctime is updated) but does not
+ * write it, but just marks it as dirty.
+ */
+
+#include "ubifs.h"
+
+/**
+ * inherit_flags - inherit flags of the parent inode.
+ * @dir: parent inode
+ * @mode: new inode mode flags
+ *
+ * This is a helper function for 'ubifs_new_inode()' which inherits flag of the
+ * parent directory inode @dir. UBIFS inodes inherit the following flags:
+ * o %UBIFS_COMPR_FL, which is useful to switch compression on/of on
+ *   sub-directory basis;
+ * o %UBIFS_SYNC_FL - useful for the same reasons;
+ * o %UBIFS_DIRSYNC_FL - similar, but relevant only to directories.
+ *
+ * This function returns the inherited flags.
+ */
+static int inherit_flags(const struct inode *dir, int mode)
+{
+	int flags;
+	const struct ubifs_inode *ui = ubifs_inode(dir);
+
+	if (!S_ISDIR(dir->i_mode))
+		/*
+		 * The parent is not a directory, which means that an extended
+		 * attribute inode is being created. No flags.
+		 */
+		return 0;
+
+	flags = ui->flags & (UBIFS_COMPR_FL | UBIFS_SYNC_FL | UBIFS_DIRSYNC_FL);
+	if (!S_ISDIR(mode))
+		/* The "DIRSYNC" flag only applies to directories */
+		flags &= ~UBIFS_DIRSYNC_FL;
+	return flags;
+}
+
+/**
+ * ubifs_new_inode - allocate new UBIFS inode object.
+ * @c: UBIFS file-system description object
+ * @dir: parent directory inode
+ * @mode: inode mode flags
+ *
+ * This function finds an unused inode number, allocates new inode and
+ * initializes it. Returns new inode in case of success and an error code in
+ * case of failure.
+ */
+struct inode *ubifs_new_inode(struct ubifs_info *c, const struct inode *dir,
+			      int mode)
+{
+	struct inode *inode;
+	struct ubifs_inode *ui;
+
+	inode = new_inode(c->vfs_sb);
+	ui = ubifs_inode(inode);
+	if (!inode)
+		return ERR_PTR(-ENOMEM);
+
+	/*
+	 * Set 'S_NOCMTIME' to prevent VFS form updating [mc]time of inodes and
+	 * marking them dirty in file write path (see 'file_update_time()').
+	 * UBIFS has to fully control "clean <-> dirty" transitions of inodes
+	 * to make budgeting work.
+	 */
+	inode->i_flags |= (S_NOCMTIME);
+
+	inode->i_uid = current->fsuid;
+	if (dir->i_mode & S_ISGID) {
+		inode->i_gid = dir->i_gid;
+		if (S_ISDIR(mode))
+			mode |= S_ISGID;
+	} else
+		inode->i_gid = current->fsgid;
+	inode->i_mode = mode;
+	inode->i_mtime = inode->i_atime = inode->i_ctime =
+			 ubifs_current_time(inode);
+	inode->i_mapping->nrpages = 0;
+	/* Disable readahead */
+	inode->i_mapping->backing_dev_info = &c->bdi;
+
+	switch (mode & S_IFMT) {
+	case S_IFREG:
+		inode->i_mapping->a_ops = &ubifs_file_address_operations;
+		inode->i_op = &ubifs_file_inode_operations;
+		inode->i_fop = &ubifs_file_operations;
+		break;
+	case S_IFDIR:
+		inode->i_op  = &ubifs_dir_inode_operations;
+		inode->i_fop = &ubifs_dir_operations;
+		inode->i_size = ui->ui_size = UBIFS_INO_NODE_SZ;
+		break;
+	case S_IFLNK:
+		inode->i_op = &ubifs_symlink_inode_operations;
+		break;
+	case S_IFSOCK:
+	case S_IFIFO:
+	case S_IFBLK:
+	case S_IFCHR:
+		inode->i_op  = &ubifs_file_inode_operations;
+		break;
+	default:
+		BUG();
+	}
+
+	ui->flags = inherit_flags(dir, mode);
+	ubifs_set_inode_flags(inode);
+	if (S_ISREG(mode))
+		ui->compr_type = c->default_compr;
+	else
+		ui->compr_type = UBIFS_COMPR_NONE;
+	ui->synced_i_size = 0;
+
+	spin_lock(&c->cnt_lock);
+	/* Inode number overflow is currently not supported */
+	if (c->highest_inum >= INUM_WARN_WATERMARK) {
+		if (c->highest_inum >= INUM_WATERMARK) {
+			spin_unlock(&c->cnt_lock);
+			ubifs_err("out of inode numbers");
+			make_bad_inode(inode);
+			iput(inode);
+			return ERR_PTR(-EINVAL);
+		}
+		ubifs_warn("running out of inode numbers (current %lu, max %d)",
+			   c->highest_inum, INUM_WATERMARK);
+	}
+
+	inode->i_ino = ++c->highest_inum;
+	inode->i_generation = ++c->vfs_gen;
+	/*
+	 * The creation sequence number remains with this inode for its
+	 * lifetime. All nodes for this inode have a greater sequence number,
+	 * and so it is possible to distinguish obsolete nodes belonging to a
+	 * previous incarnation of the same inode number - for example, for the
+	 * purpose of rebuilding the index.
+	 */
+	ui->creat_sqnum = ++c->max_sqnum;
+	spin_unlock(&c->cnt_lock);
+	return inode;
+}
+
+#ifdef CONFIG_UBIFS_FS_DEBUG
+
+static int dbg_check_name(struct ubifs_dent_node *dent, struct qstr *nm)
+{
+	if (!(ubifs_chk_flags & UBIFS_CHK_GEN))
+		return 0;
+	if (le16_to_cpu(dent->nlen) != nm->len)
+		return -EINVAL;
+	if (memcmp(dent->name, nm->name, nm->len))
+		return -EINVAL;
+	return 0;
+}
+
+#else
+
+#define dbg_check_name(dent, nm) 0
+
+#endif
+
+static struct dentry *ubifs_lookup(struct inode *dir, struct dentry *dentry,
+				   struct nameidata *nd)
+{
+	int err;
+	union ubifs_key key;
+	struct inode *inode = NULL;
+	struct ubifs_dent_node *dent;
+	struct ubifs_info *c = dir->i_sb->s_fs_info;
+
+	dbg_gen("'%.*s' in dir ino %lu",
+		dentry->d_name.len, dentry->d_name.name, dir->i_ino);
+
+	if (dentry->d_name.len > UBIFS_MAX_NLEN)
+		return ERR_PTR(-ENAMETOOLONG);
+
+	dent = kmalloc(UBIFS_MAX_DENT_NODE_SZ, GFP_NOFS);
+	if (!dent)
+		return ERR_PTR(-ENOMEM);
+
+	dent_key_init(c, &key, dir->i_ino, &dentry->d_name);
+
+	err = ubifs_tnc_lookup_nm(c, &key, dent, &dentry->d_name);
+	if (err) {
+		/*
+		 * Do not hash the direntry if parent 'i_nlink' is zero, because
+		 * this has side-effects - '->delete_inode()' call will not be
+		 * called for the parent orphan inode, because 'd_count' of its
+		 * direntry will stay 1 (it'll be negative direntry I guess)
+		 * and prevent 'iput_final()' until the dentry is destroyed due
+		 * to unmount or memory pressure.
+		 */
+		if (err == -ENOENT && dir->i_nlink != 0) {
+			dbg_gen("not found");
+			goto done;
+		}
+		goto out;
+	}
+
+	if (dbg_check_name(dent, &dentry->d_name)) {
+		err = -EINVAL;
+		goto out;
+	}
+
+	inode = ubifs_iget(dir->i_sb, le64_to_cpu(dent->inum));
+	if (IS_ERR(inode)) {
+		/*
+		 * This should not happen. Probably the file-system needs
+		 * checking.
+		 */
+		err = PTR_ERR(inode);
+		ubifs_err("dead directory entry '%.*s', error %d",
+			  dentry->d_name.len, dentry->d_name.name, err);
+		ubifs_ro_mode(c, err);
+		goto out;
+	}
+
+done:
+	kfree(dent);
+	/*
+	 * Note, d_splice_alias() would be required instead if we supported
+	 * NFS.
+	 */
+	d_add(dentry, inode);
+	return NULL;
+
+out:
+	kfree(dent);
+	return ERR_PTR(err);
+}
+
+static int ubifs_create(struct inode *dir, struct dentry *dentry, int mode,
+			struct nameidata *nd)
+{
+	struct inode *inode;
+	struct ubifs_info *c = dir->i_sb->s_fs_info;
+	int err, sz_change = CALC_DENT_SIZE(dentry->d_name.len);
+	struct ubifs_budget_req req = { .new_ino = 1, .new_dent = 1,
+					.dirtied_ino = 1 };
+	struct ubifs_inode *dir_ui = ubifs_inode(dir);
+
+	/*
+	 * Budget request settings: new inode, new direntry, changing the
+	 * parent directory inode.
+	 */
+
+	dbg_gen("dent '%.*s', mode %#x in dir ino %lu",
+		dentry->d_name.len, dentry->d_name.name, mode, dir->i_ino);
+
+	err = ubifs_budget_space(c, &req);
+	if (err)
+		return err;
+
+	inode = ubifs_new_inode(c, dir, mode);
+	if (IS_ERR(inode)) {
+		err = PTR_ERR(inode);
+		goto out_budg;
+	}
+
+	mutex_lock(&dir_ui->ui_mutex);
+	dir->i_size += sz_change;
+	dir_ui->ui_size = dir->i_size;
+	dir->i_mtime = dir->i_ctime = inode->i_ctime;
+	err = ubifs_jnl_update(c, dir, &dentry->d_name, inode, 0, 0);
+	if (err)
+		goto out_cancel;
+	mutex_unlock(&dir_ui->ui_mutex);
+
+	ubifs_release_budget(c, &req);
+	insert_inode_hash(inode);
+	d_instantiate(dentry, inode);
+	return 0;
+
+out_cancel:
+	dir->i_size -= sz_change;
+	dir_ui->ui_size = dir->i_size;
+	mutex_unlock(&dir_ui->ui_mutex);
+	make_bad_inode(inode);
+	iput(inode);
+out_budg:
+	ubifs_release_budget(c, &req);
+	ubifs_err("cannot create regular file, error %d", err);
+	return err;
+}
+
+/**
+ * vfs_dent_type - get VFS directory entry type.
+ * @type: UBIFS directory entry type
+ *
+ * This function converts UBIFS directory entry type into VFS directory entry
+ * type.
+ */
+static unsigned int vfs_dent_type(uint8_t type)
+{
+	switch (type) {
+	case UBIFS_ITYPE_REG:
+		return DT_REG;
+	case UBIFS_ITYPE_DIR:
+		return DT_DIR;
+	case UBIFS_ITYPE_LNK:
+		return DT_LNK;
+	case UBIFS_ITYPE_BLK:
+		return DT_BLK;
+	case UBIFS_ITYPE_CHR:
+		return DT_CHR;
+	case UBIFS_ITYPE_FIFO:
+		return DT_FIFO;
+	case UBIFS_ITYPE_SOCK:
+		return DT_SOCK;
+	default:
+		BUG();
+	}
+	return 0;
+}
+
+/*
+ * The classical Unix view for directory is that it is a linear array of
+ * (name, inode number) entries. Linux/VFS assumes this model as well.
+ * Particularly, 'readdir()' call wants us to return a directory entry offset
+ * which later may be used to continue 'readdir()'ing the directory or to
+ * 'seek()' to that specific direntry. Obviously UBIFS does not really fit this
+ * model because directory entries are identified by keys, which may collide.
+ *
+ * UBIFS uses directory entry hash value for directory offsets, so
+ * 'seekdir()'/'telldir()' may not always work because of possible key
+ * collisions. But UBIFS guarantees that consecutive 'readdir()' calls work
+ * properly by means of saving full directory entry name in the private field
+ * of the file description object.
+ *
+ * This means that UBIFS cannot support NFS which requires full
+ * 'seekdir()'/'telldir()' support.
+ */
+static int ubifs_readdir(struct file *file, void *dirent, filldir_t filldir)
+{
+	int err, over = 0;
+	struct qstr nm;
+	union ubifs_key key;
+	struct ubifs_dent_node *dent;
+	struct inode *dir = file->f_path.dentry->d_inode;
+	struct ubifs_info *c = dir->i_sb->s_fs_info;
+
+	dbg_gen("dir ino %lu, f_pos %#llx", dir->i_ino, file->f_pos);
+
+	if (file->f_pos > UBIFS_S_KEY_HASH_MASK || file->f_pos == 2)
+		/*
+		 * The directory was seek'ed to a senseless position or there
+		 * are no more entries.
+		 */
+		return 0;
+
+	/* File positions 0 and 1 correspond to "." and ".." */
+	if (file->f_pos == 0) {
+		ubifs_assert(!file->private_data);
+		over = filldir(dirent, ".", 1, 0, dir->i_ino, DT_DIR);
+		if (over)
+			return 0;
+		file->f_pos = 1;
+	}
+
+	if (file->f_pos == 1) {
+		ubifs_assert(!file->private_data);
+		over = filldir(dirent, "..", 2, 1,
+			       parent_ino(file->f_path.dentry), DT_DIR);
+		if (over)
+			return 0;
+
+		/* Find the first entry in TNC and save it */
+		lowest_dent_key(c, &key, dir->i_ino);
+		nm.name = NULL;
+		dent = ubifs_tnc_next_ent(c, &key, &nm);
+		if (IS_ERR(dent)) {
+			err = PTR_ERR(dent);
+			goto out;
+		}
+
+		file->f_pos = key_hash_flash(c, &dent->key);
+		file->private_data = dent;
+	}
+
+	dent = file->private_data;
+	if (!dent) {
+		/*
+		 * The directory was seek'ed to and is now readdir'ed.
+		 * Find the entry corresponding to @file->f_pos or the
+		 * closest one.
+		 */
+		dent_key_init_hash(c, &key, dir->i_ino, file->f_pos);
+		nm.name = NULL;
+		dent = ubifs_tnc_next_ent(c, &key, &nm);
+		if (IS_ERR(dent)) {
+			err = PTR_ERR(dent);
+			goto out;
+		}
+		file->f_pos = key_hash_flash(c, &dent->key);
+		file->private_data = dent;
+	}
+
+	while (1) {
+		dbg_gen("feed '%s', ino %llu, new f_pos %#x",
+			dent->name, le64_to_cpu(dent->inum),
+			key_hash_flash(c, &dent->key));
+		ubifs_assert(dent->ch.sqnum > ubifs_inode(dir)->creat_sqnum);
+
+		nm.len = le16_to_cpu(dent->nlen);
+		over = filldir(dirent, dent->name, nm.len, file->f_pos,
+			       le64_to_cpu(dent->inum),
+			       vfs_dent_type(dent->type));
+		if (over)
+			return 0;
+
+		/* Switch to the next entry */
+		key_read(c, &dent->key, &key);
+		nm.name = dent->name;
+		dent = ubifs_tnc_next_ent(c, &key, &nm);
+		if (IS_ERR(dent)) {
+			err = PTR_ERR(dent);
+			goto out;
+		}
+
+		kfree(file->private_data);
+		file->f_pos = key_hash_flash(c, &dent->key);
+		file->private_data = dent;
+		cond_resched();
+	}
+
+out:
+	if (err != -ENOENT) {
+		ubifs_err("cannot find next direntry, error %d", err);
+		return err;
+	}
+
+	kfree(file->private_data);
+	file->private_data = NULL;
+	file->f_pos = 2;
+	return 0;
+}
+
+/* If a directory is seeked, we have to free saved readdir() state */
+static loff_t ubifs_dir_llseek(struct file *file, loff_t offset, int origin)
+{
+	kfree(file->private_data);
+	file->private_data = NULL;
+	return generic_file_llseek(file, offset, origin);
+}
+
+/* Free saved readdir() state when the directory is closed */
+static int ubifs_dir_release(struct inode *dir, struct file *file)
+{
+	kfree(file->private_data);
+	file->private_data = NULL;
+	return 0;
+}
+
+/**
+ * lock_2_inodes - lock two UBIFS inodes.
+ * @inode1: first inode
+ * @inode2: second inode
+ */
+static void lock_2_inodes(struct inode *inode1, struct inode *inode2)
+{
+	if (inode1->i_ino < inode2->i_ino) {
+		mutex_lock_nested(&ubifs_inode(inode1)->ui_mutex, WB_MUTEX_2);
+		mutex_lock_nested(&ubifs_inode(inode2)->ui_mutex, WB_MUTEX_3);
+	} else {
+		mutex_lock_nested(&ubifs_inode(inode2)->ui_mutex, WB_MUTEX_2);
+		mutex_lock_nested(&ubifs_inode(inode1)->ui_mutex, WB_MUTEX_3);
+	}
+}
+
+/**
+ * unlock_2_inodes - unlock two UBIFS inodes inodes.
+ * @inode1: first inode
+ * @inode2: second inode
+ */
+static void unlock_2_inodes(struct inode *inode1, struct inode *inode2)
+{
+	mutex_unlock(&ubifs_inode(inode1)->ui_mutex);
+	mutex_unlock(&ubifs_inode(inode2)->ui_mutex);
+}
+
+static int ubifs_link(struct dentry *old_dentry, struct inode *dir,
+		      struct dentry *dentry)
+{
+	struct ubifs_info *c = dir->i_sb->s_fs_info;
+	struct inode *inode = old_dentry->d_inode;
+	struct ubifs_inode *ui = ubifs_inode(inode);
+	struct ubifs_inode *dir_ui = ubifs_inode(dir);
+	int err, sz_change = CALC_DENT_SIZE(dentry->d_name.len);
+	struct ubifs_budget_req req = { .new_dent = 1, .dirtied_ino = 2,
+					.dirtied_ino_d = ui->data_len };
+
+	/*
+	 * Budget request settings: new direntry, changing the target inode,
+	 * changing the parent inode.
+	 */
+
+	dbg_gen("dent '%.*s' to ino %lu (nlink %d) in dir ino %lu",
+		dentry->d_name.len, dentry->d_name.name, inode->i_ino,
+		inode->i_nlink, dir->i_ino);
+	err = dbg_check_synced_i_size(inode);
+	if (err)
+		return err;
+
+	err = ubifs_budget_space(c, &req);
+	if (err)
+		return err;
+
+	lock_2_inodes(dir, inode);
+	inc_nlink(inode);
+	atomic_inc(&inode->i_count);
+	inode->i_ctime = ubifs_current_time(inode);
+	dir->i_size += sz_change;
+	dir_ui->ui_size = dir->i_size;
+	dir->i_mtime = dir->i_ctime = inode->i_ctime;
+	err = ubifs_jnl_update(c, dir, &dentry->d_name, inode, 0, 0);
+	if (err)
+		goto out_cancel;
+	unlock_2_inodes(dir, inode);
+
+	ubifs_release_budget(c, &req);
+	d_instantiate(dentry, inode);
+	return 0;
+
+out_cancel:
+	dir->i_size -= sz_change;
+	dir_ui->ui_size = dir->i_size;
+	drop_nlink(inode);
+	unlock_2_inodes(dir, inode);
+	ubifs_release_budget(c, &req);
+	iput(inode);
+	return err;
+}
+
+static int ubifs_unlink(struct inode *dir, struct dentry *dentry)
+{
+	struct ubifs_info *c = dir->i_sb->s_fs_info;
+	struct inode *inode = dentry->d_inode;
+	struct ubifs_inode *dir_ui = ubifs_inode(dir);
+	int sz_change = CALC_DENT_SIZE(dentry->d_name.len);
+	int err, budgeted = 1;
+	struct ubifs_budget_req req = { .mod_dent = 1, .dirtied_ino = 2 };
+
+	/*
+	 * Budget request settings: deletion direntry, deletion inode (+1 for
+	 * @dirtied_ino), changing the parent directory inode. If budgeting
+	 * fails, go ahead anyway because we have extra space reserved for
+	 * deletions.
+	 */
+
+	dbg_gen("dent '%.*s' from ino %lu (nlink %d) in dir ino %lu",
+		dentry->d_name.len, dentry->d_name.name, inode->i_ino,
+		inode->i_nlink, dir->i_ino);
+	err = dbg_check_synced_i_size(inode);
+	if (err)
+		return err;
+
+	err = ubifs_budget_space(c, &req);
+	if (err) {
+		if (err != -ENOSPC)
+			return err;
+		err = 0;
+		budgeted = 0;
+	}
+
+	lock_2_inodes(dir, inode);
+	inode->i_ctime = ubifs_current_time(dir);
+	drop_nlink(inode);
+	dir->i_size -= sz_change;
+	dir_ui->ui_size = dir->i_size;
+	dir->i_mtime = dir->i_ctime = inode->i_ctime;
+	err = ubifs_jnl_update(c, dir, &dentry->d_name, inode, 1, 0);
+	if (err)
+		goto out_cancel;
+	unlock_2_inodes(dir, inode);
+
+	if (budgeted)
+		ubifs_release_budget(c, &req);
+	else {
+		/* We've deleted something - clean the "no space" flags */
+		c->nospace = c->nospace_rp = 0;
+		smp_wmb();
+	}
+	return 0;
+
+out_cancel:
+	dir->i_size += sz_change;
+	dir_ui->ui_size = dir->i_size;
+	inc_nlink(inode);
+	unlock_2_inodes(dir, inode);
+	if (budgeted)
+		ubifs_release_budget(c, &req);
+	return err;
+}
+
+/**
+ * check_dir_empty - check if a directory is empty or not.
+ * @c: UBIFS file-system description object
+ * @dir: VFS inode object of the directory to check
+ *
+ * This function checks if directory @dir is empty. Returns zero if the
+ * directory is empty, %-ENOTEMPTY if it is not, and other negative error codes
+ * in case of of errors.
+ */
+static int check_dir_empty(struct ubifs_info *c, struct inode *dir)
+{
+	struct qstr nm = { .name = NULL };
+	struct ubifs_dent_node *dent;
+	union ubifs_key key;
+	int err;
+
+	lowest_dent_key(c, &key, dir->i_ino);
+	dent = ubifs_tnc_next_ent(c, &key, &nm);
+	if (IS_ERR(dent)) {
+		err = PTR_ERR(dent);
+		if (err == -ENOENT)
+			err = 0;
+	} else {
+		kfree(dent);
+		err = -ENOTEMPTY;
+	}
+	return err;
+}
+
+static int ubifs_rmdir(struct inode *dir, struct dentry *dentry)
+{
+	struct ubifs_info *c = dir->i_sb->s_fs_info;
+	struct inode *inode = dentry->d_inode;
+	int sz_change = CALC_DENT_SIZE(dentry->d_name.len);
+	int err, budgeted = 1;
+	struct ubifs_inode *dir_ui = ubifs_inode(dir);
+	struct ubifs_budget_req req = { .mod_dent = 1, .dirtied_ino = 2 };
+
+	/*
+	 * Budget request settings: deletion direntry, deletion inode and
+	 * changing the parent inode. If budgeting fails, go ahead anyway
+	 * because we have extra space reserved for deletions.
+	 */
+
+	dbg_gen("directory '%.*s', ino %lu in dir ino %lu", dentry->d_name.len,
+		dentry->d_name.name, inode->i_ino, dir->i_ino);
+
+	err = check_dir_empty(c, dentry->d_inode);
+	if (err)
+		return err;
+
+	err = ubifs_budget_space(c, &req);
+	if (err) {
+		if (err != -ENOSPC)
+			return err;
+		budgeted = 0;
+	}
+
+	lock_2_inodes(dir, inode);
+	inode->i_ctime = ubifs_current_time(dir);
+	clear_nlink(inode);
+	drop_nlink(dir);
+	dir->i_size -= sz_change;
+	dir_ui->ui_size = dir->i_size;
+	dir->i_mtime = dir->i_ctime = inode->i_ctime;
+	err = ubifs_jnl_update(c, dir, &dentry->d_name, inode, 1, 0);
+	if (err)
+		goto out_cancel;
+	unlock_2_inodes(dir, inode);
+
+	if (budgeted)
+		ubifs_release_budget(c, &req);
+	else {
+		/* We've deleted something - clean the "no space" flags */
+		c->nospace = c->nospace_rp = 0;
+		smp_wmb();
+	}
+	return 0;
+
+out_cancel:
+	dir->i_size += sz_change;
+	dir_ui->ui_size = dir->i_size;
+	inc_nlink(dir);
+	inc_nlink(inode);
+	inc_nlink(inode);
+	unlock_2_inodes(dir, inode);
+	if (budgeted)
+		ubifs_release_budget(c, &req);
+	return err;
+}
+
+static int ubifs_mkdir(struct inode *dir, struct dentry *dentry, int mode)
+{
+	struct inode *inode;
+	struct ubifs_inode *dir_ui = ubifs_inode(dir);
+	struct ubifs_info *c = dir->i_sb->s_fs_info;
+	int err, sz_change = CALC_DENT_SIZE(dentry->d_name.len);
+	struct ubifs_budget_req req = { .new_ino = 1, .new_dent = 1,
+					.dirtied_ino_d = 1 };
+
+	/*
+	 * Budget request settings: new inode, new direntry and changing parent
+	 * directory inode.
+	 */
+
+	dbg_gen("dent '%.*s', mode %#x in dir ino %lu",
+		dentry->d_name.len, dentry->d_name.name, mode, dir->i_ino);
+
+	err = ubifs_budget_space(c, &req);
+	if (err)
+		return err;
+
+	inode = ubifs_new_inode(c, dir, S_IFDIR | mode);
+	if (IS_ERR(inode)) {
+		err = PTR_ERR(inode);
+		goto out_budg;
+	}
+
+	mutex_lock(&dir_ui->ui_mutex);
+	insert_inode_hash(inode);
+	inc_nlink(inode);
+	inc_nlink(dir);
+	dir->i_size += sz_change;
+	dir_ui->ui_size = dir->i_size;
+	dir->i_mtime = dir->i_ctime = inode->i_ctime;
+	err = ubifs_jnl_update(c, dir, &dentry->d_name, inode, 0, 0);
+	if (err) {
+		ubifs_err("cannot create directory, error %d", err);
+		goto out_cancel;
+	}
+	mutex_unlock(&dir_ui->ui_mutex);
+
+	ubifs_release_budget(c, &req);
+	d_instantiate(dentry, inode);
+	return 0;
+
+out_cancel:
+	dir->i_size -= sz_change;
+	dir_ui->ui_size = dir->i_size;
+	drop_nlink(dir);
+	mutex_unlock(&dir_ui->ui_mutex);
+	make_bad_inode(inode);
+	iput(inode);
+out_budg:
+	ubifs_release_budget(c, &req);
+	return err;
+}
+
+static int ubifs_mknod(struct inode *dir, struct dentry *dentry,
+		       int mode, dev_t rdev)
+{
+	struct inode *inode;
+	struct ubifs_inode *ui;
+	struct ubifs_inode *dir_ui = ubifs_inode(dir);
+	struct ubifs_info *c = dir->i_sb->s_fs_info;
+	union ubifs_dev_desc *dev = NULL;
+	int sz_change = CALC_DENT_SIZE(dentry->d_name.len);
+	int err, devlen = 0;
+	struct ubifs_budget_req req = { .new_ino = 1, .new_dent = 1,
+					.new_ino_d = devlen, .dirtied_ino = 1 };
+
+	/*
+	 * Budget request settings: new inode, new direntry and changing parent
+	 * directory inode.
+	 */
+
+	dbg_gen("dent '%.*s' in dir ino %lu",
+		dentry->d_name.len, dentry->d_name.name, dir->i_ino);
+
+	if (!new_valid_dev(rdev))
+		return -EINVAL;
+
+	if (S_ISBLK(mode) || S_ISCHR(mode)) {
+		dev = kmalloc(sizeof(union ubifs_dev_desc), GFP_NOFS);
+		if (!dev)
+			return -ENOMEM;
+		devlen = ubifs_encode_dev(dev, rdev);
+	}
+
+	err = ubifs_budget_space(c, &req);
+	if (err) {
+		kfree(dev);
+		return err;
+	}
+
+	inode = ubifs_new_inode(c, dir, mode);
+	if (IS_ERR(inode)) {
+		kfree(dev);
+		err = PTR_ERR(inode);
+		goto out_budg;
+	}
+
+	init_special_inode(inode, inode->i_mode, rdev);
+	inode->i_size = ubifs_inode(inode)->ui_size = devlen;
+	ui = ubifs_inode(inode);
+	ui->data = dev;
+	ui->data_len = devlen;
+
+	mutex_lock(&dir_ui->ui_mutex);
+	dir->i_size += sz_change;
+	dir_ui->ui_size = dir->i_size;
+	dir->i_mtime = dir->i_ctime = inode->i_ctime;
+	err = ubifs_jnl_update(c, dir, &dentry->d_name, inode, 0, 0);
+	if (err)
+		goto out_cancel;
+	mutex_unlock(&dir_ui->ui_mutex);
+
+	ubifs_release_budget(c, &req);
+	insert_inode_hash(inode);
+	d_instantiate(dentry, inode);
+	return 0;
+
+out_cancel:
+	dir->i_size -= sz_change;
+	dir_ui->ui_size = dir->i_size;
+	mutex_unlock(&dir_ui->ui_mutex);
+	make_bad_inode(inode);
+	iput(inode);
+out_budg:
+	ubifs_release_budget(c, &req);
+	return err;
+}
+
+static int ubifs_symlink(struct inode *dir, struct dentry *dentry,
+			 const char *symname)
+{
+	struct inode *inode;
+	struct ubifs_inode *ui;
+	struct ubifs_inode *dir_ui = ubifs_inode(dir);
+	struct ubifs_info *c = dir->i_sb->s_fs_info;
+	int err, len = strlen(symname);
+	int sz_change = CALC_DENT_SIZE(dentry->d_name.len);
+	struct ubifs_budget_req req = { .new_ino = 1, .new_dent = 1,
+					.new_ino_d = len, .dirtied_ino = 1 };
+
+	/*
+	 * Budget request settings: new inode, new direntry and changing parent
+	 * directory inode.
+	 */
+
+	dbg_gen("dent '%.*s', target '%s' in dir ino %lu", dentry->d_name.len,
+		dentry->d_name.name, symname, dir->i_ino);
+
+	if (len > UBIFS_MAX_INO_DATA)
+		return -ENAMETOOLONG;
+
+	err = ubifs_budget_space(c, &req);
+	if (err)
+		return err;
+
+	inode = ubifs_new_inode(c, dir, S_IFLNK | S_IRWXUGO);
+	if (IS_ERR(inode)) {
+		err = PTR_ERR(inode);
+		goto out_budg;
+	}
+
+	ui = ubifs_inode(inode);
+	ui->data = kmalloc(len + 1, GFP_NOFS);
+	if (!ui->data) {
+		err = -ENOMEM;
+		goto out_inode;
+	}
+
+	memcpy(ui->data, symname, len);
+	((char *)ui->data)[len] = '\0';
+	/*
+	 * The terminating zero byte is not written to the flash media and it
+	 * is put just to make later in-memory string processing simpler. Thus,
+	 * data length is @len, not @len + %1.
+	 */
+	ui->data_len = len;
+	inode->i_size = ubifs_inode(inode)->ui_size = len;
+
+	mutex_lock(&dir_ui->ui_mutex);
+	dir->i_size += sz_change;
+	dir_ui->ui_size = dir->i_size;
+	dir->i_mtime = dir->i_ctime = inode->i_ctime;
+	err = ubifs_jnl_update(c, dir, &dentry->d_name, inode, 0, 0);
+	if (err)
+		goto out_cancel;
+	mutex_unlock(&dir_ui->ui_mutex);
+
+	ubifs_release_budget(c, &req);
+	insert_inode_hash(inode);
+	d_instantiate(dentry, inode);
+	return 0;
+
+out_cancel:
+	dir->i_size -= sz_change;
+	dir_ui->ui_size = dir->i_size;
+	mutex_unlock(&dir_ui->ui_mutex);
+out_inode:
+	make_bad_inode(inode);
+	iput(inode);
+out_budg:
+	ubifs_release_budget(c, &req);
+	return err;
+}
+
+/**
+ * lock_3_inodes - lock three UBIFS inodes for rename.
+ * @inode1: first inode
+ * @inode2: second inode
+ * @inode3: third inode
+ *
+ * For 'ubifs_rename()', @inode1 may be the same as @inode2 whereas @inode3 may
+ * be null.
+ */
+static void lock_3_inodes(struct inode *inode1, struct inode *inode2,
+			  struct inode *inode3)
+{
+	struct inode *i1, *i2, *i3;
+
+	if (!inode3) {
+		if (inode1 != inode2) {
+			lock_2_inodes(inode1, inode2);
+			return;
+		}
+		mutex_lock_nested(&ubifs_inode(inode1)->ui_mutex, WB_MUTEX_1);
+		return;
+	}
+
+	if (inode1 == inode2) {
+		lock_2_inodes(inode1, inode3);
+		return;
+	}
+
+	/* 3 different inodes */
+	if (inode1 < inode2) {
+		i3 = inode2;
+		if (inode1 < inode3) {
+			i1 = inode1;
+			i2 = inode3;
+		} else {
+			i1 = inode3;
+			i2 = inode1;
+		}
+	} else {
+		i3 = inode1;
+		if (inode2 < inode3) {
+			i1 = inode2;
+			i2 = inode3;
+		} else {
+			i1 = inode3;
+			i2 = inode2;
+		}
+	}
+	mutex_lock_nested(&ubifs_inode(i1)->ui_mutex, WB_MUTEX_1);
+	lock_2_inodes(i2, i3);
+}
+
+/**
+ * unlock_3_inodes - unlock three UBIFS inodes for rename.
+ * @inode1: first inode
+ * @inode2: second inode
+ * @inode3: third inode
+ */
+static void unlock_3_inodes(struct inode *inode1, struct inode *inode2,
+			    struct inode *inode3)
+{
+	mutex_unlock(&ubifs_inode(inode1)->ui_mutex);
+	if (inode1 != inode2)
+		mutex_unlock(&ubifs_inode(inode2)->ui_mutex);
+	if (inode3)
+		mutex_unlock(&ubifs_inode(inode3)->ui_mutex);
+}
+
+static int ubifs_rename(struct inode *old_dir, struct dentry *old_dentry,
+			struct inode *new_dir, struct dentry *new_dentry)
+{
+	struct ubifs_info *c = old_dir->i_sb->s_fs_info;
+	struct inode *old_inode = old_dentry->d_inode;
+	struct inode *new_inode = new_dentry->d_inode;
+	struct ubifs_inode *old_inode_ui = ubifs_inode(old_inode);
+	int err, release, sync = 0, move = (new_dir != old_dir);
+	int is_dir = S_ISDIR(old_inode->i_mode);
+	int unlink = !!new_inode;
+	int new_sz = CALC_DENT_SIZE(new_dentry->d_name.len);
+	int old_sz = CALC_DENT_SIZE(old_dentry->d_name.len);
+	struct ubifs_budget_req req = { .new_dent = 1, .mod_dent = 1,
+					.dirtied_ino = 3 };
+	struct ubifs_budget_req ino_req = { .dirtied_ino = 1,
+				.dirtied_ino_d = old_inode_ui->data_len };
+	struct timespec time;
+
+	/*
+	 * Budget request settings: deletion direntry, new direntry, removing
+	 * the old inode, and changing old and new parent directory inodes.
+	 *
+	 * However, this operation also marks the target inode as dirty and
+	 * does not write it, so we allocate budget for the target inode
+	 * separately.
+	 */
+
+	dbg_gen("dent '%.*s' ino %lu in dir ino %lu to dent '%.*s' in "
+		"dir ino %lu", old_dentry->d_name.len, old_dentry->d_name.name,
+		old_inode->i_ino, old_dir->i_ino, new_dentry->d_name.len,
+		new_dentry->d_name.name, new_dir->i_ino);
+
+	if (unlink && is_dir) {
+		err = check_dir_empty(c, new_inode);
+		if (err)
+			return err;
+	}
+
+	err = ubifs_budget_space(c, &req);
+	if (err)
+		return err;
+	err = ubifs_budget_space(c, &ino_req);
+	if (err) {
+		ubifs_release_budget(c, &req);
+		return err;
+	}
+
+	lock_3_inodes(old_dir, new_dir, new_inode);
+
+	/*
+	 * Like most other Unix systems, set the @i_ctime for inodes on a
+	 * rename.
+	 */
+	time = ubifs_current_time(old_dir);
+	old_inode->i_ctime = time;
+
+	/* We must adjust parent link count when renaming directories */
+	if (is_dir) {
+		if (move) {
+			/*
+			 * @old_dir loses a link because we are moving
+			 * @old_inode to a different directory.
+			 */
+			drop_nlink(old_dir);
+			/*
+			 * @new_dir only gains a link if we are not also
+			 * overwriting an existing directory.
+			 */
+			if (!unlink)
+				inc_nlink(new_dir);
+		} else {
+			/*
+			 * @old_inode is not moving to a different directory,
+			 * but @old_dir still loses a link if we are
+			 * overwriting an existing directory.
+			 */
+			if (unlink)
+				drop_nlink(old_dir);
+		}
+	}
+
+	old_dir->i_size -= old_sz;
+	ubifs_inode(old_dir)->ui_size = old_dir->i_size;
+	old_dir->i_mtime = old_dir->i_ctime = time;
+	new_dir->i_mtime = new_dir->i_ctime = time;
+
+	/*
+	 * And finally, if we unlinked a direntry which happened to have the
+	 * same name as the moved direntry, we have to decrement @i_nlink of
+	 * the unlinked inode and change its ctime.
+	 */
+	if (unlink) {
+		/*
+		 * Directories cannot have hard-links, so if this is a
+		 * directory, decrement its @i_nlink twice because an empty
+		 * directory has @i_nlink 2.
+		 */
+		if (is_dir)
+			drop_nlink(new_inode);
+		new_inode->i_ctime = time;
+		drop_nlink(new_inode);
+	} else {
+		new_dir->i_size += new_sz;
+		ubifs_inode(new_dir)->ui_size = new_dir->i_size;
+	}
+
+	/*
+	 * Do not ask 'ubifs_jnl_rename()' to flush write-buffer if @old_inode
+	 * is dirty, because this will be done later on at the end of
+	 * 'ubifs_rename()'.
+	 */
+	if (IS_SYNC(old_inode)) {
+		sync = IS_DIRSYNC(old_dir) || IS_DIRSYNC(new_dir);
+		if (unlink && IS_SYNC(new_inode))
+			sync = 1;
+	}
+	err = ubifs_jnl_rename(c, old_dir, old_dentry, new_dir, new_dentry,
+			       sync);
+	if (err)
+		goto out_cancel;
+
+	unlock_3_inodes(old_dir, new_dir, new_inode);
+	ubifs_release_budget(c, &req);
+
+	mutex_lock(&old_inode_ui->ui_mutex);
+	release = old_inode_ui->dirty;
+	mark_inode_dirty_sync(old_inode);
+	mutex_unlock(&old_inode_ui->ui_mutex);
+
+	if (release)
+		ubifs_release_budget(c, &ino_req);
+	if (IS_SYNC(old_inode))
+		err = old_inode->i_sb->s_op->write_inode(old_inode, 1);
+	return err;
+
+out_cancel:
+	if (unlink) {
+		if (is_dir)
+			inc_nlink(new_inode);
+		inc_nlink(new_inode);
+	} else {
+		new_dir->i_size -= new_sz;
+		ubifs_inode(new_dir)->ui_size = new_dir->i_size;
+	}
+	old_dir->i_size += old_sz;
+	ubifs_inode(old_dir)->ui_size = old_dir->i_size;
+	if (is_dir) {
+		if (move) {
+			inc_nlink(old_dir);
+			if (!unlink)
+				drop_nlink(new_dir);
+		} else {
+			if (unlink)
+				inc_nlink(old_dir);
+		}
+	}
+	unlock_3_inodes(old_dir, new_dir, new_inode);
+	ubifs_release_budget(c, &ino_req);
+	ubifs_release_budget(c, &req);
+	return err;
+}
+
+int ubifs_getattr(struct vfsmount *mnt, struct dentry *dentry,
+		  struct kstat *stat)
+{
+	loff_t size;
+	struct inode *inode = dentry->d_inode;
+	struct ubifs_inode *ui = ubifs_inode(inode);
+
+	mutex_lock(&ui->ui_mutex);
+	stat->dev = inode->i_sb->s_dev;
+	stat->ino = inode->i_ino;
+	stat->mode = inode->i_mode;
+	stat->nlink = inode->i_nlink;
+	stat->uid = inode->i_uid;
+	stat->gid = inode->i_gid;
+	stat->rdev = inode->i_rdev;
+	stat->atime = inode->i_atime;
+	stat->mtime = inode->i_mtime;
+	stat->ctime = inode->i_ctime;
+	stat->blksize = UBIFS_BLOCK_SIZE;
+	stat->size = ui->ui_size;
+
+	/*
+	 * Unfortunately, the 'stat()' system call was designed for block
+	 * device based file systems, and it is not appropriate for UBIFS,
+	 * because UBIFS does not have notion of "block". For example, it is
+	 * difficult to tell how many block a directory takes - it actually
+	 * takes less than 300 bytes, but we have to round it to block size,
+	 * which introduces large mistake. This makes utilities like 'du' to
+	 * report completely senseless numbers. This is the reason why UBIFS
+	 * goes the same way as JFFS2 - it reports zero blocks for everything
+	 * but regular files, which makes more sense than reporting completely
+	 * wrong sizes.
+	 */
+	if (S_ISREG(inode->i_mode)) {
+		size = ui->xattr_size;
+		size += stat->size;
+		size = ALIGN(size, UBIFS_BLOCK_SIZE);
+		/*
+		 * Note, user-space expects 512-byte blocks count irrespectively
+		 * of what was reported in @stat->size.
+		 */
+		stat->blocks = size >> 9;
+	} else
+		stat->blocks = 0;
+	mutex_unlock(&ui->ui_mutex);
+	return 0;
+}
+
+struct inode_operations ubifs_dir_inode_operations = {
+	.lookup      = ubifs_lookup,
+	.create      = ubifs_create,
+	.link        = ubifs_link,
+	.symlink     = ubifs_symlink,
+	.unlink      = ubifs_unlink,
+	.mkdir       = ubifs_mkdir,
+	.rmdir       = ubifs_rmdir,
+	.mknod       = ubifs_mknod,
+	.rename      = ubifs_rename,
+	.setattr     = ubifs_setattr,
+	.getattr     = ubifs_getattr,
+#ifdef CONFIG_UBIFS_FS_XATTR
+	.setxattr    = ubifs_setxattr,
+	.getxattr    = ubifs_getxattr,
+	.listxattr   = ubifs_listxattr,
+	.removexattr = ubifs_removexattr,
+#endif
+};
+
+struct file_operations ubifs_dir_operations = {
+	.llseek         = ubifs_dir_llseek,
+	.release        = ubifs_dir_release,
+	.read           = generic_read_dir,
+	.readdir        = ubifs_readdir,
+	.fsync          = ubifs_fsync,
+	.unlocked_ioctl = ubifs_ioctl,
+#ifdef CONFIG_COMPAT
+	.compat_ioctl   = ubifs_compat_ioctl,
+#endif
+};
diff --git a/fs/ubifs/file.c b/fs/ubifs/file.c
new file mode 100644
index 00000000000..005a3b854d9
--- /dev/null
+++ b/fs/ubifs/file.c
@@ -0,0 +1,1275 @@
+/*
+ * This file is part of UBIFS.
+ *
+ * Copyright (C) 2006-2008 Nokia Corporation.
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 as published by
+ * the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
+ * more details.
+ *
+ * You should have received a copy of the GNU General Public License along with
+ * this program; if not, write to the Free Software Foundation, Inc., 51
+ * Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
+ *
+ * Authors: Artem Bityutskiy (Битюцкий Артём)
+ *          Adrian Hunter
+ */
+
+/*
+ * This file implements VFS file and inode operations of regular files, device
+ * nodes and symlinks as well as address space operations.
+ *
+ * UBIFS uses 2 page flags: PG_private and PG_checked. PG_private is set if the
+ * page is dirty and is used for budgeting purposes - dirty pages should not be
+ * budgeted. The PG_checked flag is set if full budgeting is required for the
+ * page e.g., when it corresponds to a file hole or it is just beyond the file
+ * size. The budgeting is done in 'ubifs_write_begin()', because it is OK to
+ * fail in this function, and the budget is released in 'ubifs_write_end()'. So
+ * the PG_private and PG_checked flags carry the information about how the page
+ * was budgeted, to make it possible to release the budget properly.
+ *
+ * A thing to keep in mind: inode's 'i_mutex' is locked in most VFS operations
+ * we implement. However, this is not true for '->writepage()', which might be
+ * called with 'i_mutex' unlocked. For example, when pdflush is performing
+ * write-back, it calls 'writepage()' with unlocked 'i_mutex', although the
+ * inode has 'I_LOCK' flag in this case. At "normal" work-paths 'i_mutex' is
+ * locked in '->writepage', e.g. in "sys_write -> alloc_pages -> direct reclaim
+ * path'. So, in '->writepage()' we are only guaranteed that the page is
+ * locked.
+ *
+ * Similarly, 'i_mutex' does not have to be locked in readpage(), e.g.,
+ * readahead path does not have it locked ("sys_read -> generic_file_aio_read
+ * -> ondemand_readahead -> readpage"). In case of readahead, 'I_LOCK' flag is
+ * not set as well. However, UBIFS disables readahead.
+ *
+ * This, for example means that there might be 2 concurrent '->writepage()'
+ * calls for the same inode, but different inode dirty pages.
+ */
+
+#include "ubifs.h"
+#include <linux/mount.h>
+
+static int read_block(struct inode *inode, void *addr, unsigned int block,
+		      struct ubifs_data_node *dn)
+{
+	struct ubifs_info *c = inode->i_sb->s_fs_info;
+	int err, len, out_len;
+	union ubifs_key key;
+	unsigned int dlen;
+
+	data_key_init(c, &key, inode->i_ino, block);
+	err = ubifs_tnc_lookup(c, &key, dn);
+	if (err) {
+		if (err == -ENOENT)
+			/* Not found, so it must be a hole */
+			memset(addr, 0, UBIFS_BLOCK_SIZE);
+		return err;
+	}
+
+	ubifs_assert(dn->ch.sqnum > ubifs_inode(inode)->creat_sqnum);
+
+	len = le32_to_cpu(dn->size);
+	if (len <= 0 || len > UBIFS_BLOCK_SIZE)
+		goto dump;
+
+	dlen = le32_to_cpu(dn->ch.len) - UBIFS_DATA_NODE_SZ;
+	out_len = UBIFS_BLOCK_SIZE;
+	err = ubifs_decompress(&dn->data, dlen, addr, &out_len,
+			       le16_to_cpu(dn->compr_type));
+	if (err || len != out_len)
+		goto dump;
+
+	/*
+	 * Data length can be less than a full block, even for blocks that are
+	 * not the last in the file (e.g., as a result of making a hole and
+	 * appending data). Ensure that the remainder is zeroed out.
+	 */
+	if (len < UBIFS_BLOCK_SIZE)
+		memset(addr + len, 0, UBIFS_BLOCK_SIZE - len);
+
+	return 0;
+
+dump:
+	ubifs_err("bad data node (block %u, inode %lu)",
+		  block, inode->i_ino);
+	dbg_dump_node(c, dn);
+	return -EINVAL;
+}
+
+static int do_readpage(struct page *page)
+{
+	void *addr;
+	int err = 0, i;
+	unsigned int block, beyond;
+	struct ubifs_data_node *dn;
+	struct inode *inode = page->mapping->host;
+	loff_t i_size = i_size_read(inode);
+
+	dbg_gen("ino %lu, pg %lu, i_size %lld, flags %#lx",
+		inode->i_ino, page->index, i_size, page->flags);
+	ubifs_assert(!PageChecked(page));
+	ubifs_assert(!PagePrivate(page));
+
+	addr = kmap(page);
+
+	block = page->index << UBIFS_BLOCKS_PER_PAGE_SHIFT;
+	beyond = (i_size + UBIFS_BLOCK_SIZE - 1) >> UBIFS_BLOCK_SHIFT;
+	if (block >= beyond) {
+		/* Reading beyond inode */
+		SetPageChecked(page);
+		memset(addr, 0, PAGE_CACHE_SIZE);
+		goto out;
+	}
+
+	dn = kmalloc(UBIFS_MAX_DATA_NODE_SZ, GFP_NOFS);
+	if (!dn) {
+		err = -ENOMEM;
+		goto error;
+	}
+
+	i = 0;
+	while (1) {
+		int ret;
+
+		if (block >= beyond) {
+			/* Reading beyond inode */
+			err = -ENOENT;
+			memset(addr, 0, UBIFS_BLOCK_SIZE);
+		} else {
+			ret = read_block(inode, addr, block, dn);
+			if (ret) {
+				err = ret;
+				if (err != -ENOENT)
+					break;
+			}
+		}
+		if (++i >= UBIFS_BLOCKS_PER_PAGE)
+			break;
+		block += 1;
+		addr += UBIFS_BLOCK_SIZE;
+	}
+	if (err) {
+		if (err == -ENOENT) {
+			/* Not found, so it must be a hole */
+			SetPageChecked(page);
+			dbg_gen("hole");
+			goto out_free;
+		}
+		ubifs_err("cannot read page %lu of inode %lu, error %d",
+			  page->index, inode->i_ino, err);
+		goto error;
+	}
+
+out_free:
+	kfree(dn);
+out:
+	SetPageUptodate(page);
+	ClearPageError(page);
+	flush_dcache_page(page);
+	kunmap(page);
+	return 0;
+
+error:
+	kfree(dn);
+	ClearPageUptodate(page);
+	SetPageError(page);
+	flush_dcache_page(page);
+	kunmap(page);
+	return err;
+}
+
+/**
+ * release_new_page_budget - release budget of a new page.
+ * @c: UBIFS file-system description object
+ *
+ * This is a helper function which releases budget corresponding to the budget
+ * of one new page of data.
+ */
+static void release_new_page_budget(struct ubifs_info *c)
+{
+	struct ubifs_budget_req req = { .recalculate = 1, .new_page = 1 };
+
+	ubifs_release_budget(c, &req);
+}
+
+/**
+ * release_existing_page_budget - release budget of an existing page.
+ * @c: UBIFS file-system description object
+ *
+ * This is a helper function which releases budget corresponding to the budget
+ * of changing one one page of data which already exists on the flash media.
+ */
+static void release_existing_page_budget(struct ubifs_info *c)
+{
+	struct ubifs_budget_req req = { .dd_growth = c->page_budget};
+
+	ubifs_release_budget(c, &req);
+}
+
+static int write_begin_slow(struct address_space *mapping,
+			    loff_t pos, unsigned len, struct page **pagep)
+{
+	struct inode *inode = mapping->host;
+	struct ubifs_info *c = inode->i_sb->s_fs_info;
+	pgoff_t index = pos >> PAGE_CACHE_SHIFT;
+	struct ubifs_budget_req req = { .new_page = 1 };
+	int uninitialized_var(err), appending = !!(pos + len > inode->i_size);
+	struct page *page;
+
+	dbg_gen("ino %lu, pos %llu, len %u, i_size %lld",
+		inode->i_ino, pos, len, inode->i_size);
+
+	/*
+	 * At the slow path we have to budget before locking the page, because
+	 * budgeting may force write-back, which would wait on locked pages and
+	 * deadlock if we had the page locked. At this point we do not know
+	 * anything about the page, so assume that this is a new page which is
+	 * written to a hole. This corresponds to largest budget. Later the
+	 * budget will be amended if this is not true.
+	 */
+	if (appending)
+		/* We are appending data, budget for inode change */
+		req.dirtied_ino = 1;
+
+	err = ubifs_budget_space(c, &req);
+	if (unlikely(err))
+		return err;
+
+	page = __grab_cache_page(mapping, index);
+	if (unlikely(!page)) {
+		ubifs_release_budget(c, &req);
+		return -ENOMEM;
+	}
+
+	if (!PageUptodate(page)) {
+		if (!(pos & PAGE_CACHE_MASK) && len == PAGE_CACHE_SIZE)
+			SetPageChecked(page);
+		else {
+			err = do_readpage(page);
+			if (err) {
+				unlock_page(page);
+				page_cache_release(page);
+				return err;
+			}
+		}
+
+		SetPageUptodate(page);
+		ClearPageError(page);
+	}
+
+	if (PagePrivate(page))
+		/*
+		 * The page is dirty, which means it was budgeted twice:
+		 *   o first time the budget was allocated by the task which
+		 *     made the page dirty and set the PG_private flag;
+		 *   o and then we budgeted for it for the second time at the
+		 *     very beginning of this function.
+		 *
+		 * So what we have to do is to release the page budget we
+		 * allocated.
+		 */
+		release_new_page_budget(c);
+	else if (!PageChecked(page))
+		/*
+		 * We are changing a page which already exists on the media.
+		 * This means that changing the page does not make the amount
+		 * of indexing information larger, and this part of the budget
+		 * which we have already acquired may be released.
+		 */
+		ubifs_convert_page_budget(c);
+
+	if (appending) {
+		struct ubifs_inode *ui = ubifs_inode(inode);
+
+		/*
+		 * 'ubifs_write_end()' is optimized from the fast-path part of
+		 * 'ubifs_write_begin()' and expects the @ui_mutex to be locked
+		 * if data is appended.
+		 */
+		mutex_lock(&ui->ui_mutex);
+		if (ui->dirty)
+			/*
+			 * The inode is dirty already, so we may free the
+			 * budget we allocated.
+			 */
+			ubifs_release_dirty_inode_budget(c, ui);
+	}
+
+	*pagep = page;
+	return 0;
+}
+
+/**
+ * allocate_budget - allocate budget for 'ubifs_write_begin()'.
+ * @c: UBIFS file-system description object
+ * @page: page to allocate budget for
+ * @ui: UBIFS inode object the page belongs to
+ * @appending: non-zero if the page is appended
+ *
+ * This is a helper function for 'ubifs_write_begin()' which allocates budget
+ * for the operation. The budget is allocated differently depending on whether
+ * this is appending, whether the page is dirty or not, and so on. This
+ * function leaves the @ui->ui_mutex locked in case of appending. Returns zero
+ * in case of success and %-ENOSPC in case of failure.
+ */
+static int allocate_budget(struct ubifs_info *c, struct page *page,
+			   struct ubifs_inode *ui, int appending)
+{
+	struct ubifs_budget_req req = { .fast = 1 };
+
+	if (PagePrivate(page)) {
+		if (!appending)
+			/*
+			 * The page is dirty and we are not appending, which
+			 * means no budget is needed at all.
+			 */
+			return 0;
+
+		mutex_lock(&ui->ui_mutex);
+		if (ui->dirty)
+			/*
+			 * The page is dirty and we are appending, so the inode
+			 * has to be marked as dirty. However, it is already
+			 * dirty, so we do not need any budget. We may return,
+			 * but @ui->ui_mutex hast to be left locked because we
+			 * should prevent write-back from flushing the inode
+			 * and freeing the budget. The lock will be released in
+			 * 'ubifs_write_end()'.
+			 */
+			return 0;
+
+		/*
+		 * The page is dirty, we are appending, the inode is clean, so
+		 * we need to budget the inode change.
+		 */
+		req.dirtied_ino = 1;
+	} else {
+		if (PageChecked(page))
+			/*
+			 * The page corresponds to a hole and does not
+			 * exist on the media. So changing it makes
+			 * make the amount of indexing information
+			 * larger, and we have to budget for a new
+			 * page.
+			 */
+			req.new_page = 1;
+		else
+			/*
+			 * Not a hole, the change will not add any new
+			 * indexing information, budget for page
+			 * change.
+			 */
+			req.dirtied_page = 1;
+
+		if (appending) {
+			mutex_lock(&ui->ui_mutex);
+			if (!ui->dirty)
+				/*
+				 * The inode is clean but we will have to mark
+				 * it as dirty because we are appending. This
+				 * needs a budget.
+				 */
+				req.dirtied_ino = 1;
+		}
+	}
+
+	return ubifs_budget_space(c, &req);
+}
+
+/*
+ * This function is called when a page of data is going to be written. Since
+ * the page of data will not necessarily go to the flash straight away, UBIFS
+ * has to reserve space on the media for it, which is done by means of
+ * budgeting.
+ *
+ * This is the hot-path of the file-system and we are trying to optimize it as
+ * much as possible. For this reasons it is split on 2 parts - slow and fast.
+ *
+ * There many budgeting cases:
+ *     o a new page is appended - we have to budget for a new page and for
+ *       changing the inode; however, if the inode is already dirty, there is
+ *       no need to budget for it;
+ *     o an existing clean page is changed - we have budget for it; if the page
+ *       does not exist on the media (a hole), we have to budget for a new
+ *       page; otherwise, we may budget for changing an existing page; the
+ *       difference between these cases is that changing an existing page does
+ *       not introduce anything new to the FS indexing information, so it does
+ *       not grow, and smaller budget is acquired in this case;
+ *     o an existing dirty page is changed - no need to budget at all, because
+ *       the page budget has been acquired by earlier, when the page has been
+ *       marked dirty.
+ *
+ * UBIFS budgeting sub-system may force write-back if it thinks there is no
+ * space to reserve. This imposes some locking restrictions and makes it
+ * impossible to take into account the above cases, and makes it impossible to
+ * optimize budgeting.
+ *
+ * The solution for this is that the fast path of 'ubifs_write_begin()' assumes
+ * there is a plenty of flash space and the budget will be acquired quickly,
+ * without forcing write-back. The slow path does not make this assumption.
+ */
+static int ubifs_write_begin(struct file *file, struct address_space *mapping,
+			     loff_t pos, unsigned len, unsigned flags,
+			     struct page **pagep, void **fsdata)
+{
+	struct inode *inode = mapping->host;
+	struct ubifs_info *c = inode->i_sb->s_fs_info;
+	struct ubifs_inode *ui = ubifs_inode(inode);
+	pgoff_t index = pos >> PAGE_CACHE_SHIFT;
+	int uninitialized_var(err), appending = !!(pos + len > inode->i_size);
+	struct page *page;
+
+
+	ubifs_assert(ubifs_inode(inode)->ui_size == inode->i_size);
+
+	if (unlikely(c->ro_media))
+		return -EROFS;
+
+	/* Try out the fast-path part first */
+	page = __grab_cache_page(mapping, index);
+	if (unlikely(!page))
+		return -ENOMEM;
+
+	if (!PageUptodate(page)) {
+		/* The page is not loaded from the flash */
+		if (!(pos & PAGE_CACHE_MASK) && len == PAGE_CACHE_SIZE)
+			/*
+			 * We change whole page so no need to load it. But we
+			 * have to set the @PG_checked flag to make the further
+			 * code the page is new. This might be not true, but it
+			 * is better to budget more that to read the page from
+			 * the media.
+			 */
+			SetPageChecked(page);
+		else {
+			err = do_readpage(page);
+			if (err) {
+				unlock_page(page);
+				page_cache_release(page);
+				return err;
+			}
+		}
+
+		SetPageUptodate(page);
+		ClearPageError(page);
+	}
+
+	err = allocate_budget(c, page, ui, appending);
+	if (unlikely(err)) {
+		ubifs_assert(err == -ENOSPC);
+		/*
+		 * Budgeting failed which means it would have to force
+		 * write-back but didn't, because we set the @fast flag in the
+		 * request. Write-back cannot be done now, while we have the
+		 * page locked, because it would deadlock. Unlock and free
+		 * everything and fall-back to slow-path.
+		 */
+		if (appending) {
+			ubifs_assert(mutex_is_locked(&ui->ui_mutex));
+			mutex_unlock(&ui->ui_mutex);
+		}
+		unlock_page(page);
+		page_cache_release(page);
+
+		return write_begin_slow(mapping, pos, len, pagep);
+	}
+
+	/*
+	 * Whee, we aquired budgeting quickly - without involving
+	 * garbage-collection, committing or forceing write-back. We return
+	 * with @ui->ui_mutex locked if we are appending pages, and unlocked
+	 * otherwise. This is an optimization (slightly hacky though).
+	 */
+	*pagep = page;
+	return 0;
+
+}
+
+/**
+ * cancel_budget - cancel budget.
+ * @c: UBIFS file-system description object
+ * @page: page to cancel budget for
+ * @ui: UBIFS inode object the page belongs to
+ * @appending: non-zero if the page is appended
+ *
+ * This is a helper function for a page write operation. It unlocks the
+ * @ui->ui_mutex in case of appending.
+ */
+static void cancel_budget(struct ubifs_info *c, struct page *page,
+			  struct ubifs_inode *ui, int appending)
+{
+	if (appending) {
+		if (!ui->dirty)
+			ubifs_release_dirty_inode_budget(c, ui);
+		mutex_unlock(&ui->ui_mutex);
+	}
+	if (!PagePrivate(page)) {
+		if (PageChecked(page))
+			release_new_page_budget(c);
+		else
+			release_existing_page_budget(c);
+	}
+}
+
+static int ubifs_write_end(struct file *file, struct address_space *mapping,
+			   loff_t pos, unsigned len, unsigned copied,
+			   struct page *page, void *fsdata)
+{
+	struct inode *inode = mapping->host;
+	struct ubifs_inode *ui = ubifs_inode(inode);
+	struct ubifs_info *c = inode->i_sb->s_fs_info;
+	loff_t end_pos = pos + len;
+	int appending = !!(end_pos > inode->i_size);
+
+	dbg_gen("ino %lu, pos %llu, pg %lu, len %u, copied %d, i_size %lld",
+		inode->i_ino, pos, page->index, len, copied, inode->i_size);
+
+	if (unlikely(copied < len && len == PAGE_CACHE_SIZE)) {
+		/*
+		 * VFS copied less data to the page that it intended and
+		 * declared in its '->write_begin()' call via the @len
+		 * argument. If the page was not up-to-date, and @len was
+		 * @PAGE_CACHE_SIZE, the 'ubifs_write_begin()' function did
+		 * not load it from the media (for optimization reasons). This
+		 * means that part of the page contains garbage. So read the
+		 * page now.
+		 */
+		dbg_gen("copied %d instead of %d, read page and repeat",
+			copied, len);
+		cancel_budget(c, page, ui, appending);
+
+		/*
+		 * Return 0 to force VFS to repeat the whole operation, or the
+		 * error code if 'do_readpage()' failes.
+		 */
+		copied = do_readpage(page);
+		goto out;
+	}
+
+	if (!PagePrivate(page)) {
+		SetPagePrivate(page);
+		atomic_long_inc(&c->dirty_pg_cnt);
+		__set_page_dirty_nobuffers(page);
+	}
+
+	if (appending) {
+		i_size_write(inode, end_pos);
+		ui->ui_size = end_pos;
+		/*
+		 * Note, we do not set @I_DIRTY_PAGES (which means that the
+		 * inode has dirty pages), this has been done in
+		 * '__set_page_dirty_nobuffers()'.
+		 */
+		__mark_inode_dirty(inode, I_DIRTY_DATASYNC);
+		ubifs_assert(mutex_is_locked(&ui->ui_mutex));
+		mutex_unlock(&ui->ui_mutex);
+	}
+
+out:
+	unlock_page(page);
+	page_cache_release(page);
+	return copied;
+}
+
+static int ubifs_readpage(struct file *file, struct page *page)
+{
+	do_readpage(page);
+	unlock_page(page);
+	return 0;
+}
+
+static int do_writepage(struct page *page, int len)
+{
+	int err = 0, i, blen;
+	unsigned int block;
+	void *addr;
+	union ubifs_key key;
+	struct inode *inode = page->mapping->host;
+	struct ubifs_info *c = inode->i_sb->s_fs_info;
+
+#ifdef UBIFS_DEBUG
+	spin_lock(&ui->ui_lock);
+	ubifs_assert(page->index <= ui->synced_i_size << PAGE_CACHE_SIZE);
+	spin_unlock(&ui->ui_lock);
+#endif
+
+	/* Update radix tree tags */
+	set_page_writeback(page);
+
+	addr = kmap(page);
+	block = page->index << UBIFS_BLOCKS_PER_PAGE_SHIFT;
+	i = 0;
+	while (len) {
+		blen = min_t(int, len, UBIFS_BLOCK_SIZE);
+		data_key_init(c, &key, inode->i_ino, block);
+		err = ubifs_jnl_write_data(c, inode, &key, addr, blen);
+		if (err)
+			break;
+		if (++i >= UBIFS_BLOCKS_PER_PAGE)
+			break;
+		block += 1;
+		addr += blen;
+		len -= blen;
+	}
+	if (err) {
+		SetPageError(page);
+		ubifs_err("cannot write page %lu of inode %lu, error %d",
+			  page->index, inode->i_ino, err);
+		ubifs_ro_mode(c, err);
+	}
+
+	ubifs_assert(PagePrivate(page));
+	if (PageChecked(page))
+		release_new_page_budget(c);
+	else
+		release_existing_page_budget(c);
+
+	atomic_long_dec(&c->dirty_pg_cnt);
+	ClearPagePrivate(page);
+	ClearPageChecked(page);
+
+	kunmap(page);
+	unlock_page(page);
+	end_page_writeback(page);
+	return err;
+}
+
+/*
+ * When writing-back dirty inodes, VFS first writes-back pages belonging to the
+ * inode, then the inode itself. For UBIFS this may cause a problem. Consider a
+ * situation when a we have an inode with size 0, then a megabyte of data is
+ * appended to the inode, then write-back starts and flushes some amount of the
+ * dirty pages, the journal becomes full, commit happens and finishes, and then
+ * an unclean reboot happens. When the file system is mounted next time, the
+ * inode size would still be 0, but there would be many pages which are beyond
+ * the inode size, they would be indexed and consume flash space. Because the
+ * journal has been committed, the replay would not be able to detect this
+ * situation and correct the inode size. This means UBIFS would have to scan
+ * whole index and correct all inode sizes, which is long an unacceptable.
+ *
+ * To prevent situations like this, UBIFS writes pages back only if they are
+ * within last synchronized inode size, i.e. the the size which has been
+ * written to the flash media last time. Otherwise, UBIFS forces inode
+ * write-back, thus making sure the on-flash inode contains current inode size,
+ * and then keeps writing pages back.
+ *
+ * Some locking issues explanation. 'ubifs_writepage()' first is called with
+ * the page locked, and it locks @ui_mutex. However, write-back does take inode
+ * @i_mutex, which means other VFS operations may be run on this inode at the
+ * same time. And the problematic one is truncation to smaller size, from where
+ * we have to call 'vmtruncate()', which first changes @inode->i_size, then
+ * drops the truncated pages. And while dropping the pages, it takes the page
+ * lock. This means that 'do_truncation()' cannot call 'vmtruncate()' with
+ * @ui_mutex locked, because it would deadlock with 'ubifs_writepage()'. This
+ * means that @inode->i_size is changed while @ui_mutex is unlocked.
+ *
+ * But in 'ubifs_writepage()' we have to guarantee that we do not write beyond
+ * inode size. How do we do this if @inode->i_size may became smaller while we
+ * are in the middle of 'ubifs_writepage()'? The UBIFS solution is the
+ * @ui->ui_isize "shadow" field which UBIFS uses instead of @inode->i_size
+ * internally and updates it under @ui_mutex.
+ *
+ * Q: why we do not worry that if we race with truncation, we may end up with a
+ * situation when the inode is truncated while we are in the middle of
+ * 'do_writepage()', so we do write beyond inode size?
+ * A: If we are in the middle of 'do_writepage()', truncation would be locked
+ * on the page lock and it would not write the truncated inode node to the
+ * journal before we have finished.
+ */
+static int ubifs_writepage(struct page *page, struct writeback_control *wbc)
+{
+	struct inode *inode = page->mapping->host;
+	struct ubifs_inode *ui = ubifs_inode(inode);
+	loff_t i_size =  i_size_read(inode), synced_i_size;
+	pgoff_t end_index = i_size >> PAGE_CACHE_SHIFT;
+	int err, len = i_size & (PAGE_CACHE_SIZE - 1);
+	void *kaddr;
+
+	dbg_gen("ino %lu, pg %lu, pg flags %#lx",
+		inode->i_ino, page->index, page->flags);
+	ubifs_assert(PagePrivate(page));
+
+	/* Is the page fully outside @i_size? (truncate in progress) */
+	if (page->index > end_index || (page->index == end_index && !len)) {
+		err = 0;
+		goto out_unlock;
+	}
+
+	spin_lock(&ui->ui_lock);
+	synced_i_size = ui->synced_i_size;
+	spin_unlock(&ui->ui_lock);
+
+	/* Is the page fully inside @i_size? */
+	if (page->index < end_index) {
+		if (page->index >= synced_i_size >> PAGE_CACHE_SHIFT) {
+			err = inode->i_sb->s_op->write_inode(inode, 1);
+			if (err)
+				goto out_unlock;
+			/*
+			 * The inode has been written, but the write-buffer has
+			 * not been synchronized, so in case of an unclean
+			 * reboot we may end up with some pages beyond inode
+			 * size, but they would be in the journal (because
+			 * commit flushes write buffers) and recovery would deal
+			 * with this.
+			 */
+		}
+		return do_writepage(page, PAGE_CACHE_SIZE);
+	}
+
+	/*
+	 * The page straddles @i_size. It must be zeroed out on each and every
+	 * writepage invocation because it may be mmapped. "A file is mapped
+	 * in multiples of the page size. For a file that is not a multiple of
+	 * the page size, the remaining memory is zeroed when mapped, and
+	 * writes to that region are not written out to the file."
+	 */
+	kaddr = kmap_atomic(page, KM_USER0);
+	memset(kaddr + len, 0, PAGE_CACHE_SIZE - len);
+	flush_dcache_page(page);
+	kunmap_atomic(kaddr, KM_USER0);
+
+	if (i_size > synced_i_size) {
+		err = inode->i_sb->s_op->write_inode(inode, 1);
+		if (err)
+			goto out_unlock;
+	}
+
+	return do_writepage(page, len);
+
+out_unlock:
+	unlock_page(page);
+	return err;
+}
+
+/**
+ * do_attr_changes - change inode attributes.
+ * @inode: inode to change attributes for
+ * @attr: describes attributes to change
+ */
+static void do_attr_changes(struct inode *inode, const struct iattr *attr)
+{
+	if (attr->ia_valid & ATTR_UID)
+		inode->i_uid = attr->ia_uid;
+	if (attr->ia_valid & ATTR_GID)
+		inode->i_gid = attr->ia_gid;
+	if (attr->ia_valid & ATTR_ATIME)
+		inode->i_atime = timespec_trunc(attr->ia_atime,
+						inode->i_sb->s_time_gran);
+	if (attr->ia_valid & ATTR_MTIME)
+		inode->i_mtime = timespec_trunc(attr->ia_mtime,
+						inode->i_sb->s_time_gran);
+	if (attr->ia_valid & ATTR_CTIME)
+		inode->i_ctime = timespec_trunc(attr->ia_ctime,
+						inode->i_sb->s_time_gran);
+	if (attr->ia_valid & ATTR_MODE) {
+		umode_t mode = attr->ia_mode;
+
+		if (!in_group_p(inode->i_gid) && !capable(CAP_FSETID))
+			mode &= ~S_ISGID;
+		inode->i_mode = mode;
+	}
+}
+
+/**
+ * do_truncation - truncate an inode.
+ * @c: UBIFS file-system description object
+ * @inode: inode to truncate
+ * @attr: inode attribute changes description
+ *
+ * This function implements VFS '->setattr()' call when the inode is truncated
+ * to a smaller size. Returns zero in case of success and a negative error code
+ * in case of failure.
+ */
+static int do_truncation(struct ubifs_info *c, struct inode *inode,
+			 const struct iattr *attr)
+{
+	int err;
+	struct ubifs_budget_req req;
+	loff_t old_size = inode->i_size, new_size = attr->ia_size;
+	int offset = new_size & (UBIFS_BLOCK_SIZE - 1);
+	struct ubifs_inode *ui = ubifs_inode(inode);
+
+	dbg_gen("ino %lu, size %lld -> %lld", inode->i_ino, old_size, new_size);
+	memset(&req, 0, sizeof(struct ubifs_budget_req));
+
+	/*
+	 * If this is truncation to a smaller size, and we do not truncate on a
+	 * block boundary, budget for changing one data block, because the last
+	 * block will be re-written.
+	 */
+	if (new_size & (UBIFS_BLOCK_SIZE - 1))
+		req.dirtied_page = 1;
+
+	req.dirtied_ino = 1;
+	/* A funny way to budget for truncation node */
+	req.dirtied_ino_d = UBIFS_TRUN_NODE_SZ;
+	err = ubifs_budget_space(c, &req);
+	if (err)
+		return err;
+
+	err = vmtruncate(inode, new_size);
+	if (err)
+		goto out_budg;
+
+	if (offset) {
+		pgoff_t index = new_size >> PAGE_CACHE_SHIFT;
+		struct page *page;
+
+		page = find_lock_page(inode->i_mapping, index);
+		if (page) {
+			if (PageDirty(page)) {
+				/*
+				 * 'ubifs_jnl_truncate()' will try to truncate
+				 * the last data node, but it contains
+				 * out-of-date data because the page is dirty.
+				 * Write the page now, so that
+				 * 'ubifs_jnl_truncate()' will see an already
+				 * truncated (and up to date) data node.
+				 */
+				ubifs_assert(PagePrivate(page));
+
+				clear_page_dirty_for_io(page);
+				if (UBIFS_BLOCKS_PER_PAGE_SHIFT)
+					offset = new_size &
+						 (PAGE_CACHE_SIZE - 1);
+				err = do_writepage(page, offset);
+				page_cache_release(page);
+				if (err)
+					goto out_budg;
+				/*
+				 * We could now tell 'ubifs_jnl_truncate()' not
+				 * to read the last block.
+				 */
+			} else {
+				/*
+				 * We could 'kmap()' the page and pass the data
+				 * to 'ubifs_jnl_truncate()' to save it from
+				 * having to read it.
+				 */
+				unlock_page(page);
+				page_cache_release(page);
+			}
+		}
+	}
+
+	mutex_lock(&ui->ui_mutex);
+	ui->ui_size = inode->i_size;
+	/* Truncation changes inode [mc]time */
+	inode->i_mtime = inode->i_ctime = ubifs_current_time(inode);
+	/* The other attributes may be changed at the same time as well */
+	do_attr_changes(inode, attr);
+
+	err = ubifs_jnl_truncate(c, inode, old_size, new_size);
+	mutex_unlock(&ui->ui_mutex);
+out_budg:
+	ubifs_release_budget(c, &req);
+	return err;
+}
+
+/**
+ * do_setattr - change inode attributes.
+ * @c: UBIFS file-system description object
+ * @inode: inode to change attributes for
+ * @attr: inode attribute changes description
+ *
+ * This function implements VFS '->setattr()' call for all cases except
+ * truncations to smaller size. Returns zero in case of success and a negative
+ * error code in case of failure.
+ */
+static int do_setattr(struct ubifs_info *c, struct inode *inode,
+		      const struct iattr *attr)
+{
+	int err, release;
+	loff_t new_size = attr->ia_size;
+	struct ubifs_inode *ui = ubifs_inode(inode);
+	struct ubifs_budget_req req = { .dirtied_ino = 1,
+					.dirtied_ino_d = ui->data_len };
+
+	err = ubifs_budget_space(c, &req);
+	if (err)
+		return err;
+
+	if (attr->ia_valid & ATTR_SIZE) {
+		dbg_gen("size %lld -> %lld", inode->i_size, new_size);
+		err = vmtruncate(inode, new_size);
+		if (err)
+			goto out;
+	}
+
+	mutex_lock(&ui->ui_mutex);
+	if (attr->ia_valid & ATTR_SIZE) {
+		/* Truncation changes inode [mc]time */
+		inode->i_mtime = inode->i_ctime = ubifs_current_time(inode);
+		/* 'vmtruncate()' changed @i_size, update @ui_size */
+		ui->ui_size = inode->i_size;
+	}
+
+	do_attr_changes(inode, attr);
+
+	release = ui->dirty;
+	if (attr->ia_valid & ATTR_SIZE)
+		/*
+		 * Inode length changed, so we have to make sure
+		 * @I_DIRTY_DATASYNC is set.
+		 */
+		 __mark_inode_dirty(inode, I_DIRTY_SYNC | I_DIRTY_DATASYNC);
+	else
+		mark_inode_dirty_sync(inode);
+	mutex_unlock(&ui->ui_mutex);
+
+	if (release)
+		ubifs_release_budget(c, &req);
+	if (IS_SYNC(inode))
+		err = inode->i_sb->s_op->write_inode(inode, 1);
+	return err;
+
+out:
+	ubifs_release_budget(c, &req);
+	return err;
+}
+
+int ubifs_setattr(struct dentry *dentry, struct iattr *attr)
+{
+	int err;
+	struct inode *inode = dentry->d_inode;
+	struct ubifs_info *c = inode->i_sb->s_fs_info;
+
+	dbg_gen("ino %lu, ia_valid %#x", inode->i_ino, attr->ia_valid);
+	err = inode_change_ok(inode, attr);
+	if (err)
+		return err;
+
+	err = dbg_check_synced_i_size(inode);
+	if (err)
+		return err;
+
+	if ((attr->ia_valid & ATTR_SIZE) && attr->ia_size < inode->i_size)
+		/* Truncation to a smaller size */
+		err = do_truncation(c, inode, attr);
+	else
+		err = do_setattr(c, inode, attr);
+
+	return err;
+}
+
+static void ubifs_invalidatepage(struct page *page, unsigned long offset)
+{
+	struct inode *inode = page->mapping->host;
+	struct ubifs_info *c = inode->i_sb->s_fs_info;
+
+	ubifs_assert(PagePrivate(page));
+	if (offset)
+		/* Partial page remains dirty */
+		return;
+
+	if (PageChecked(page))
+		release_new_page_budget(c);
+	else
+		release_existing_page_budget(c);
+
+	atomic_long_dec(&c->dirty_pg_cnt);
+	ClearPagePrivate(page);
+	ClearPageChecked(page);
+}
+
+static void *ubifs_follow_link(struct dentry *dentry, struct nameidata *nd)
+{
+	struct ubifs_inode *ui = ubifs_inode(dentry->d_inode);
+
+	nd_set_link(nd, ui->data);
+	return NULL;
+}
+
+int ubifs_fsync(struct file *file, struct dentry *dentry, int datasync)
+{
+	struct inode *inode = dentry->d_inode;
+	struct ubifs_info *c = inode->i_sb->s_fs_info;
+	int err;
+
+	dbg_gen("syncing inode %lu", inode->i_ino);
+
+	/*
+	 * VFS has already synchronized dirty pages for this inode. Synchronize
+	 * the inode unless this is a 'datasync()' call.
+	 */
+	if (!datasync || (inode->i_state & I_DIRTY_DATASYNC)) {
+		err = inode->i_sb->s_op->write_inode(inode, 1);
+		if (err)
+			return err;
+	}
+
+	/*
+	 * Nodes related to this inode may still sit in a write-buffer. Flush
+	 * them.
+	 */
+	err = ubifs_sync_wbufs_by_inode(c, inode);
+	if (err)
+		return err;
+
+	return 0;
+}
+
+/**
+ * mctime_update_needed - check if mtime or ctime update is needed.
+ * @inode: the inode to do the check for
+ * @now: current time
+ *
+ * This helper function checks if the inode mtime/ctime should be updated or
+ * not. If current values of the time-stamps are within the UBIFS inode time
+ * granularity, they are not updated. This is an optimization.
+ */
+static inline int mctime_update_needed(const struct inode *inode,
+				       const struct timespec *now)
+{
+	if (!timespec_equal(&inode->i_mtime, now) ||
+	    !timespec_equal(&inode->i_ctime, now))
+		return 1;
+	return 0;
+}
+
+/**
+ * update_ctime - update mtime and ctime of an inode.
+ * @c: UBIFS file-system description object
+ * @inode: inode to update
+ *
+ * This function updates mtime and ctime of the inode if it is not equivalent to
+ * current time. Returns zero in case of success and a negative error code in
+ * case of failure.
+ */
+static int update_mctime(struct ubifs_info *c, struct inode *inode)
+{
+	struct timespec now = ubifs_current_time(inode);
+	struct ubifs_inode *ui = ubifs_inode(inode);
+
+	if (mctime_update_needed(inode, &now)) {
+		int err, release;
+		struct ubifs_budget_req req = { .dirtied_ino = 1,
+						.dirtied_ino_d = ui->data_len };
+
+		err = ubifs_budget_space(c, &req);
+		if (err)
+			return err;
+
+		mutex_lock(&ui->ui_mutex);
+		inode->i_mtime = inode->i_ctime = ubifs_current_time(inode);
+		release = ui->dirty;
+		mark_inode_dirty_sync(inode);
+		mutex_unlock(&ui->ui_mutex);
+		if (release)
+			ubifs_release_budget(c, &req);
+	}
+
+	return 0;
+}
+
+static ssize_t ubifs_aio_write(struct kiocb *iocb, const struct iovec *iov,
+			       unsigned long nr_segs, loff_t pos)
+{
+	int err;
+	ssize_t ret;
+	struct inode *inode = iocb->ki_filp->f_mapping->host;
+	struct ubifs_info *c = inode->i_sb->s_fs_info;
+
+	err = update_mctime(c, inode);
+	if (err)
+		return err;
+
+	ret = generic_file_aio_write(iocb, iov, nr_segs, pos);
+	if (ret < 0)
+		return ret;
+
+	if (ret > 0 && (IS_SYNC(inode) || iocb->ki_filp->f_flags & O_SYNC)) {
+		err = ubifs_sync_wbufs_by_inode(c, inode);
+		if (err)
+			return err;
+	}
+
+	return ret;
+}
+
+static int ubifs_set_page_dirty(struct page *page)
+{
+	int ret;
+
+	ret = __set_page_dirty_nobuffers(page);
+	/*
+	 * An attempt to dirty a page without budgeting for it - should not
+	 * happen.
+	 */
+	ubifs_assert(ret == 0);
+	return ret;
+}
+
+static int ubifs_releasepage(struct page *page, gfp_t unused_gfp_flags)
+{
+	/*
+	 * An attempt to release a dirty page without budgeting for it - should
+	 * not happen.
+	 */
+	if (PageWriteback(page))
+		return 0;
+	ubifs_assert(PagePrivate(page));
+	ubifs_assert(0);
+	ClearPagePrivate(page);
+	ClearPageChecked(page);
+	return 1;
+}
+
+/*
+ * mmap()d file has taken write protection fault and is being made
+ * writable. UBIFS must ensure page is budgeted for.
+ */
+static int ubifs_vm_page_mkwrite(struct vm_area_struct *vma, struct page *page)
+{
+	struct inode *inode = vma->vm_file->f_path.dentry->d_inode;
+	struct ubifs_info *c = inode->i_sb->s_fs_info;
+	struct timespec now = ubifs_current_time(inode);
+	struct ubifs_budget_req req = { .new_page = 1 };
+	int err, update_time;
+
+	dbg_gen("ino %lu, pg %lu, i_size %lld",	inode->i_ino, page->index,
+		i_size_read(inode));
+	ubifs_assert(!(inode->i_sb->s_flags & MS_RDONLY));
+
+	if (unlikely(c->ro_media))
+		return -EROFS;
+
+	/*
+	 * We have not locked @page so far so we may budget for changing the
+	 * page. Note, we cannot do this after we locked the page, because
+	 * budgeting may cause write-back which would cause deadlock.
+	 *
+	 * At the moment we do not know whether the page is dirty or not, so we
+	 * assume that it is not and budget for a new page. We could look at
+	 * the @PG_private flag and figure this out, but we may race with write
+	 * back and the page state may change by the time we lock it, so this
+	 * would need additional care. We do not bother with this at the
+	 * moment, although it might be good idea to do. Instead, we allocate
+	 * budget for a new page and amend it later on if the page was in fact
+	 * dirty.
+	 *
+	 * The budgeting-related logic of this function is similar to what we
+	 * do in 'ubifs_write_begin()' and 'ubifs_write_end()'. Glance there
+	 * for more comments.
+	 */
+	update_time = mctime_update_needed(inode, &now);
+	if (update_time)
+		/*
+		 * We have to change inode time stamp which requires extra
+		 * budgeting.
+		 */
+		req.dirtied_ino = 1;
+
+	err = ubifs_budget_space(c, &req);
+	if (unlikely(err)) {
+		if (err == -ENOSPC)
+			ubifs_warn("out of space for mmapped file "
+				   "(inode number %lu)", inode->i_ino);
+		return err;
+	}
+
+	lock_page(page);
+	if (unlikely(page->mapping != inode->i_mapping ||
+		     page_offset(page) > i_size_read(inode))) {
+		/* Page got truncated out from underneath us */
+		err = -EINVAL;
+		goto out_unlock;
+	}
+
+	if (PagePrivate(page))
+		release_new_page_budget(c);
+	else {
+		if (!PageChecked(page))
+			ubifs_convert_page_budget(c);
+		SetPagePrivate(page);
+		atomic_long_inc(&c->dirty_pg_cnt);
+		__set_page_dirty_nobuffers(page);
+	}
+
+	if (update_time) {
+		int release;
+		struct ubifs_inode *ui = ubifs_inode(inode);
+
+		mutex_lock(&ui->ui_mutex);
+		inode->i_mtime = inode->i_ctime = ubifs_current_time(inode);
+		release = ui->dirty;
+		mark_inode_dirty_sync(inode);
+		mutex_unlock(&ui->ui_mutex);
+		if (release)
+			ubifs_release_dirty_inode_budget(c, ui);
+	}
+
+	unlock_page(page);
+	return 0;
+
+out_unlock:
+	unlock_page(page);
+	ubifs_release_budget(c, &req);
+	return err;
+}
+
+static struct vm_operations_struct ubifs_file_vm_ops = {
+	.fault        = filemap_fault,
+	.page_mkwrite = ubifs_vm_page_mkwrite,
+};
+
+static int ubifs_file_mmap(struct file *file, struct vm_area_struct *vma)
+{
+	int err;
+
+	/* 'generic_file_mmap()' takes care of NOMMU case */
+	err = generic_file_mmap(file, vma);
+	if (err)
+		return err;
+	vma->vm_ops = &ubifs_file_vm_ops;
+	return 0;
+}
+
+struct address_space_operations ubifs_file_address_operations = {
+	.readpage       = ubifs_readpage,
+	.writepage      = ubifs_writepage,
+	.write_begin    = ubifs_write_begin,
+	.write_end      = ubifs_write_end,
+	.invalidatepage = ubifs_invalidatepage,
+	.set_page_dirty = ubifs_set_page_dirty,
+	.releasepage    = ubifs_releasepage,
+};
+
+struct inode_operations ubifs_file_inode_operations = {
+	.setattr     = ubifs_setattr,
+	.getattr     = ubifs_getattr,
+#ifdef CONFIG_UBIFS_FS_XATTR
+	.setxattr    = ubifs_setxattr,
+	.getxattr    = ubifs_getxattr,
+	.listxattr   = ubifs_listxattr,
+	.removexattr = ubifs_removexattr,
+#endif
+};
+
+struct inode_operations ubifs_symlink_inode_operations = {
+	.readlink    = generic_readlink,
+	.follow_link = ubifs_follow_link,
+	.setattr     = ubifs_setattr,
+	.getattr     = ubifs_getattr,
+};
+
+struct file_operations ubifs_file_operations = {
+	.llseek         = generic_file_llseek,
+	.read           = do_sync_read,
+	.write          = do_sync_write,
+	.aio_read       = generic_file_aio_read,
+	.aio_write      = ubifs_aio_write,
+	.mmap           = ubifs_file_mmap,
+	.fsync          = ubifs_fsync,
+	.unlocked_ioctl = ubifs_ioctl,
+	.splice_read	= generic_file_splice_read,
+#ifdef CONFIG_COMPAT
+	.compat_ioctl   = ubifs_compat_ioctl,
+#endif
+};
diff --git a/fs/ubifs/find.c b/fs/ubifs/find.c
new file mode 100644
index 00000000000..10394c54836
--- /dev/null
+++ b/fs/ubifs/find.c
@@ -0,0 +1,975 @@
+/*
+ * This file is part of UBIFS.
+ *
+ * Copyright (C) 2006-2008 Nokia Corporation.
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 as published by
+ * the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
+ * more details.
+ *
+ * You should have received a copy of the GNU General Public License along with
+ * this program; if not, write to the Free Software Foundation, Inc., 51
+ * Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
+ *
+ * Authors: Artem Bityutskiy (Битюцкий Артём)
+ *          Adrian Hunter
+ */
+
+/*
+ * This file contains functions for finding LEBs for various purposes e.g.
+ * garbage collection. In general, lprops category heaps and lists are used
+ * for fast access, falling back on scanning the LPT as a last resort.
+ */
+
+#include <linux/sort.h>
+#include "ubifs.h"
+
+/**
+ * struct scan_data - data provided to scan callback functions
+ * @min_space: minimum number of bytes for which to scan
+ * @pick_free: whether it is OK to scan for empty LEBs
+ * @lnum: LEB number found is returned here
+ * @exclude_index: whether to exclude index LEBs
+ */
+struct scan_data {
+	int min_space;
+	int pick_free;
+	int lnum;
+	int exclude_index;
+};
+
+/**
+ * valuable - determine whether LEB properties are valuable.
+ * @c: the UBIFS file-system description object
+ * @lprops: LEB properties
+ *
+ * This function return %1 if the LEB properties should be added to the LEB
+ * properties tree in memory. Otherwise %0 is returned.
+ */
+static int valuable(struct ubifs_info *c, const struct ubifs_lprops *lprops)
+{
+	int n, cat = lprops->flags & LPROPS_CAT_MASK;
+	struct ubifs_lpt_heap *heap;
+
+	switch (cat) {
+	case LPROPS_DIRTY:
+	case LPROPS_DIRTY_IDX:
+	case LPROPS_FREE:
+		heap = &c->lpt_heap[cat - 1];
+		if (heap->cnt < heap->max_cnt)
+			return 1;
+		if (lprops->free + lprops->dirty >= c->dark_wm)
+			return 1;
+		return 0;
+	case LPROPS_EMPTY:
+		n = c->lst.empty_lebs + c->freeable_cnt -
+		    c->lst.taken_empty_lebs;
+		if (n < c->lsave_cnt)
+			return 1;
+		return 0;
+	case LPROPS_FREEABLE:
+		return 1;
+	case LPROPS_FRDI_IDX:
+		return 1;
+	}
+	return 0;
+}
+
+/**
+ * scan_for_dirty_cb - dirty space scan callback.
+ * @c: the UBIFS file-system description object
+ * @lprops: LEB properties to scan
+ * @in_tree: whether the LEB properties are in main memory
+ * @data: information passed to and from the caller of the scan
+ *
+ * This function returns a code that indicates whether the scan should continue
+ * (%LPT_SCAN_CONTINUE), whether the LEB properties should be added to the tree
+ * in main memory (%LPT_SCAN_ADD), or whether the scan should stop
+ * (%LPT_SCAN_STOP).
+ */
+static int scan_for_dirty_cb(struct ubifs_info *c,
+			     const struct ubifs_lprops *lprops, int in_tree,
+			     struct scan_data *data)
+{
+	int ret = LPT_SCAN_CONTINUE;
+
+	/* Exclude LEBs that are currently in use */
+	if (lprops->flags & LPROPS_TAKEN)
+		return LPT_SCAN_CONTINUE;
+	/* Determine whether to add these LEB properties to the tree */
+	if (!in_tree && valuable(c, lprops))
+		ret |= LPT_SCAN_ADD;
+	/* Exclude LEBs with too little space */
+	if (lprops->free + lprops->dirty < data->min_space)
+		return ret;
+	/* If specified, exclude index LEBs */
+	if (data->exclude_index && lprops->flags & LPROPS_INDEX)
+		return ret;
+	/* If specified, exclude empty or freeable LEBs */
+	if (lprops->free + lprops->dirty == c->leb_size) {
+		if (!data->pick_free)
+			return ret;
+	/* Exclude LEBs with too little dirty space (unless it is empty) */
+	} else if (lprops->dirty < c->dead_wm)
+		return ret;
+	/* Finally we found space */
+	data->lnum = lprops->lnum;
+	return LPT_SCAN_ADD | LPT_SCAN_STOP;
+}
+
+/**
+ * scan_for_dirty - find a data LEB with free space.
+ * @c: the UBIFS file-system description object
+ * @min_space: minimum amount free plus dirty space the returned LEB has to
+ *             have
+ * @pick_free: if it is OK to return a free or freeable LEB
+ * @exclude_index: whether to exclude index LEBs
+ *
+ * This function returns a pointer to the LEB properties found or a negative
+ * error code.
+ */
+static const struct ubifs_lprops *scan_for_dirty(struct ubifs_info *c,
+						 int min_space, int pick_free,
+						 int exclude_index)
+{
+	const struct ubifs_lprops *lprops;
+	struct ubifs_lpt_heap *heap;
+	struct scan_data data;
+	int err, i;
+
+	/* There may be an LEB with enough dirty space on the free heap */
+	heap = &c->lpt_heap[LPROPS_FREE - 1];
+	for (i = 0; i < heap->cnt; i++) {
+		lprops = heap->arr[i];
+		if (lprops->free + lprops->dirty < min_space)
+			continue;
+		if (lprops->dirty < c->dead_wm)
+			continue;
+		return lprops;
+	}
+	/*
+	 * A LEB may have fallen off of the bottom of the dirty heap, and ended
+	 * up as uncategorized even though it has enough dirty space for us now,
+	 * so check the uncategorized list. N.B. neither empty nor freeable LEBs
+	 * can end up as uncategorized because they are kept on lists not
+	 * finite-sized heaps.
+	 */
+	list_for_each_entry(lprops, &c->uncat_list, list) {
+		if (lprops->flags & LPROPS_TAKEN)
+			continue;
+		if (lprops->free + lprops->dirty < min_space)
+			continue;
+		if (exclude_index && (lprops->flags & LPROPS_INDEX))
+			continue;
+		if (lprops->dirty < c->dead_wm)
+			continue;
+		return lprops;
+	}
+	/* We have looked everywhere in main memory, now scan the flash */
+	if (c->pnodes_have >= c->pnode_cnt)
+		/* All pnodes are in memory, so skip scan */
+		return ERR_PTR(-ENOSPC);
+	data.min_space = min_space;
+	data.pick_free = pick_free;
+	data.lnum = -1;
+	data.exclude_index = exclude_index;
+	err = ubifs_lpt_scan_nolock(c, -1, c->lscan_lnum,
+				    (ubifs_lpt_scan_callback)scan_for_dirty_cb,
+				    &data);
+	if (err)
+		return ERR_PTR(err);
+	ubifs_assert(data.lnum >= c->main_first && data.lnum < c->leb_cnt);
+	c->lscan_lnum = data.lnum;
+	lprops = ubifs_lpt_lookup_dirty(c, data.lnum);
+	if (IS_ERR(lprops))
+		return lprops;
+	ubifs_assert(lprops->lnum == data.lnum);
+	ubifs_assert(lprops->free + lprops->dirty >= min_space);
+	ubifs_assert(lprops->dirty >= c->dead_wm ||
+		     (pick_free &&
+		      lprops->free + lprops->dirty == c->leb_size));
+	ubifs_assert(!(lprops->flags & LPROPS_TAKEN));
+	ubifs_assert(!exclude_index || !(lprops->flags & LPROPS_INDEX));
+	return lprops;
+}
+
+/**
+ * ubifs_find_dirty_leb - find a dirty LEB for the Garbage Collector.
+ * @c: the UBIFS file-system description object
+ * @ret_lp: LEB properties are returned here on exit
+ * @min_space: minimum amount free plus dirty space the returned LEB has to
+ *             have
+ * @pick_free: controls whether it is OK to pick empty or index LEBs
+ *
+ * This function tries to find a dirty logical eraseblock which has at least
+ * @min_space free and dirty space. It prefers to take an LEB from the dirty or
+ * dirty index heap, and it falls-back to LPT scanning if the heaps are empty
+ * or do not have an LEB which satisfies the @min_space criteria.
+ *
+ * Note:
+ *   o LEBs which have less than dead watermark of dirty space are never picked
+ *   by this function;
+ *
+ * Returns zero and the LEB properties of
+ * found dirty LEB in case of success, %-ENOSPC if no dirty LEB was found and a
+ * negative error code in case of other failures. The returned LEB is marked as
+ * "taken".
+ *
+ * The additional @pick_free argument controls if this function has to return a
+ * free or freeable LEB if one is present. For example, GC must to set it to %1,
+ * when called from the journal space reservation function, because the
+ * appearance of free space may coincide with the loss of enough dirty space
+ * for GC to succeed anyway.
+ *
+ * In contrast, if the Garbage Collector is called from budgeting, it should
+ * just make free space, not return LEBs which are already free or freeable.
+ *
+ * In addition @pick_free is set to %2 by the recovery process in order to
+ * recover gc_lnum in which case an index LEB must not be returned.
+ */
+int ubifs_find_dirty_leb(struct ubifs_info *c, struct ubifs_lprops *ret_lp,
+			 int min_space, int pick_free)
+{
+	int err = 0, sum, exclude_index = pick_free == 2 ? 1 : 0;
+	const struct ubifs_lprops *lp = NULL, *idx_lp = NULL;
+	struct ubifs_lpt_heap *heap, *idx_heap;
+
+	ubifs_get_lprops(c);
+
+	if (pick_free) {
+		int lebs, rsvd_idx_lebs = 0;
+
+		spin_lock(&c->space_lock);
+		lebs = c->lst.empty_lebs;
+		lebs += c->freeable_cnt - c->lst.taken_empty_lebs;
+
+		/*
+		 * Note, the index may consume more LEBs than have been reserved
+		 * for it. It is OK because it might be consolidated by GC.
+		 * But if the index takes fewer LEBs than it is reserved for it,
+		 * this function must avoid picking those reserved LEBs.
+		 */
+		if (c->min_idx_lebs >= c->lst.idx_lebs) {
+			rsvd_idx_lebs = c->min_idx_lebs -  c->lst.idx_lebs;
+			exclude_index = 1;
+		}
+		spin_unlock(&c->space_lock);
+
+		/* Check if there are enough free LEBs for the index */
+		if (rsvd_idx_lebs < lebs) {
+			/* OK, try to find an empty LEB */
+			lp = ubifs_fast_find_empty(c);
+			if (lp)
+				goto found;
+
+			/* Or a freeable LEB */
+			lp = ubifs_fast_find_freeable(c);
+			if (lp)
+				goto found;
+		} else
+			/*
+			 * We cannot pick free/freeable LEBs in the below code.
+			 */
+			pick_free = 0;
+	} else {
+		spin_lock(&c->space_lock);
+		exclude_index = (c->min_idx_lebs >= c->lst.idx_lebs);
+		spin_unlock(&c->space_lock);
+	}
+
+	/* Look on the dirty and dirty index heaps */
+	heap = &c->lpt_heap[LPROPS_DIRTY - 1];
+	idx_heap = &c->lpt_heap[LPROPS_DIRTY_IDX - 1];
+
+	if (idx_heap->cnt && !exclude_index) {
+		idx_lp = idx_heap->arr[0];
+		sum = idx_lp->free + idx_lp->dirty;
+		/*
+		 * Since we reserve twice as more space for the index than it
+		 * actually takes, it does not make sense to pick indexing LEBs
+		 * with less than half LEB of dirty space.
+		 */
+		if (sum < min_space || sum < c->half_leb_size)
+			idx_lp = NULL;
+	}
+
+	if (heap->cnt) {
+		lp = heap->arr[0];
+		if (lp->dirty + lp->free < min_space)
+			lp = NULL;
+	}
+
+	/* Pick the LEB with most space */
+	if (idx_lp && lp) {
+		if (idx_lp->free + idx_lp->dirty >= lp->free + lp->dirty)
+			lp = idx_lp;
+	} else if (idx_lp && !lp)
+		lp = idx_lp;
+
+	if (lp) {
+		ubifs_assert(lp->dirty >= c->dead_wm);
+		goto found;
+	}
+
+	/* Did not find a dirty LEB on the dirty heaps, have to scan */
+	dbg_find("scanning LPT for a dirty LEB");
+	lp = scan_for_dirty(c, min_space, pick_free, exclude_index);
+	if (IS_ERR(lp)) {
+		err = PTR_ERR(lp);
+		goto out;
+	}
+	ubifs_assert(lp->dirty >= c->dead_wm ||
+		     (pick_free && lp->free + lp->dirty == c->leb_size));
+
+found:
+	dbg_find("found LEB %d, free %d, dirty %d, flags %#x",
+		 lp->lnum, lp->free, lp->dirty, lp->flags);
+
+	lp = ubifs_change_lp(c, lp, LPROPS_NC, LPROPS_NC,
+			     lp->flags | LPROPS_TAKEN, 0);
+	if (IS_ERR(lp)) {
+		err = PTR_ERR(lp);
+		goto out;
+	}
+
+	memcpy(ret_lp, lp, sizeof(struct ubifs_lprops));
+
+out:
+	ubifs_release_lprops(c);
+	return err;
+}
+
+/**
+ * scan_for_free_cb - free space scan callback.
+ * @c: the UBIFS file-system description object
+ * @lprops: LEB properties to scan
+ * @in_tree: whether the LEB properties are in main memory
+ * @data: information passed to and from the caller of the scan
+ *
+ * This function returns a code that indicates whether the scan should continue
+ * (%LPT_SCAN_CONTINUE), whether the LEB properties should be added to the tree
+ * in main memory (%LPT_SCAN_ADD), or whether the scan should stop
+ * (%LPT_SCAN_STOP).
+ */
+static int scan_for_free_cb(struct ubifs_info *c,
+			    const struct ubifs_lprops *lprops, int in_tree,
+			    struct scan_data *data)
+{
+	int ret = LPT_SCAN_CONTINUE;
+
+	/* Exclude LEBs that are currently in use */
+	if (lprops->flags & LPROPS_TAKEN)
+		return LPT_SCAN_CONTINUE;
+	/* Determine whether to add these LEB properties to the tree */
+	if (!in_tree && valuable(c, lprops))
+		ret |= LPT_SCAN_ADD;
+	/* Exclude index LEBs */
+	if (lprops->flags & LPROPS_INDEX)
+		return ret;
+	/* Exclude LEBs with too little space */
+	if (lprops->free < data->min_space)
+		return ret;
+	/* If specified, exclude empty LEBs */
+	if (!data->pick_free && lprops->free == c->leb_size)
+		return ret;
+	/*
+	 * LEBs that have only free and dirty space must not be allocated
+	 * because they may have been unmapped already or they may have data
+	 * that is obsolete only because of nodes that are still sitting in a
+	 * wbuf.
+	 */
+	if (lprops->free + lprops->dirty == c->leb_size && lprops->dirty > 0)
+		return ret;
+	/* Finally we found space */
+	data->lnum = lprops->lnum;
+	return LPT_SCAN_ADD | LPT_SCAN_STOP;
+}
+
+/**
+ * do_find_free_space - find a data LEB with free space.
+ * @c: the UBIFS file-system description object
+ * @min_space: minimum amount of free space required
+ * @pick_free: whether it is OK to scan for empty LEBs
+ * @squeeze: whether to try to find space in a non-empty LEB first
+ *
+ * This function returns a pointer to the LEB properties found or a negative
+ * error code.
+ */
+static
+const struct ubifs_lprops *do_find_free_space(struct ubifs_info *c,
+					      int min_space, int pick_free,
+					      int squeeze)
+{
+	const struct ubifs_lprops *lprops;
+	struct ubifs_lpt_heap *heap;
+	struct scan_data data;
+	int err, i;
+
+	if (squeeze) {
+		lprops = ubifs_fast_find_free(c);
+		if (lprops && lprops->free >= min_space)
+			return lprops;
+	}
+	if (pick_free) {
+		lprops = ubifs_fast_find_empty(c);
+		if (lprops)
+			return lprops;
+	}
+	if (!squeeze) {
+		lprops = ubifs_fast_find_free(c);
+		if (lprops && lprops->free >= min_space)
+			return lprops;
+	}
+	/* There may be an LEB with enough free space on the dirty heap */
+	heap = &c->lpt_heap[LPROPS_DIRTY - 1];
+	for (i = 0; i < heap->cnt; i++) {
+		lprops = heap->arr[i];
+		if (lprops->free >= min_space)
+			return lprops;
+	}
+	/*
+	 * A LEB may have fallen off of the bottom of the free heap, and ended
+	 * up as uncategorized even though it has enough free space for us now,
+	 * so check the uncategorized list. N.B. neither empty nor freeable LEBs
+	 * can end up as uncategorized because they are kept on lists not
+	 * finite-sized heaps.
+	 */
+	list_for_each_entry(lprops, &c->uncat_list, list) {
+		if (lprops->flags & LPROPS_TAKEN)
+			continue;
+		if (lprops->flags & LPROPS_INDEX)
+			continue;
+		if (lprops->free >= min_space)
+			return lprops;
+	}
+	/* We have looked everywhere in main memory, now scan the flash */
+	if (c->pnodes_have >= c->pnode_cnt)
+		/* All pnodes are in memory, so skip scan */
+		return ERR_PTR(-ENOSPC);
+	data.min_space = min_space;
+	data.pick_free = pick_free;
+	data.lnum = -1;
+	err = ubifs_lpt_scan_nolock(c, -1, c->lscan_lnum,
+				    (ubifs_lpt_scan_callback)scan_for_free_cb,
+				    &data);
+	if (err)
+		return ERR_PTR(err);
+	ubifs_assert(data.lnum >= c->main_first && data.lnum < c->leb_cnt);
+	c->lscan_lnum = data.lnum;
+	lprops = ubifs_lpt_lookup_dirty(c, data.lnum);
+	if (IS_ERR(lprops))
+		return lprops;
+	ubifs_assert(lprops->lnum == data.lnum);
+	ubifs_assert(lprops->free >= min_space);
+	ubifs_assert(!(lprops->flags & LPROPS_TAKEN));
+	ubifs_assert(!(lprops->flags & LPROPS_INDEX));
+	return lprops;
+}
+
+/**
+ * ubifs_find_free_space - find a data LEB with free space.
+ * @c: the UBIFS file-system description object
+ * @min_space: minimum amount of required free space
+ * @free: contains amount of free space in the LEB on exit
+ * @squeeze: whether to try to find space in a non-empty LEB first
+ *
+ * This function looks for an LEB with at least @min_space bytes of free space.
+ * It tries to find an empty LEB if possible. If no empty LEBs are available,
+ * this function searches for a non-empty data LEB. The returned LEB is marked
+ * as "taken".
+ *
+ * This function returns found LEB number in case of success, %-ENOSPC if it
+ * failed to find a LEB with @min_space bytes of free space and other a negative
+ * error codes in case of failure.
+ */
+int ubifs_find_free_space(struct ubifs_info *c, int min_space, int *free,
+			  int squeeze)
+{
+	const struct ubifs_lprops *lprops;
+	int lebs, rsvd_idx_lebs, pick_free = 0, err, lnum, flags;
+
+	dbg_find("min_space %d", min_space);
+	ubifs_get_lprops(c);
+
+	/* Check if there are enough empty LEBs for commit */
+	spin_lock(&c->space_lock);
+	if (c->min_idx_lebs > c->lst.idx_lebs)
+		rsvd_idx_lebs = c->min_idx_lebs -  c->lst.idx_lebs;
+	else
+		rsvd_idx_lebs = 0;
+	lebs = c->lst.empty_lebs + c->freeable_cnt + c->idx_gc_cnt -
+	       c->lst.taken_empty_lebs;
+	ubifs_assert(lebs + c->lst.idx_lebs >= c->min_idx_lebs);
+	if (rsvd_idx_lebs < lebs)
+		/*
+		 * OK to allocate an empty LEB, but we still don't want to go
+		 * looking for one if there aren't any.
+		 */
+		if (c->lst.empty_lebs - c->lst.taken_empty_lebs > 0) {
+			pick_free = 1;
+			/*
+			 * Because we release the space lock, we must account
+			 * for this allocation here. After the LEB properties
+			 * flags have been updated, we subtract one. Note, the
+			 * result of this is that lprops also decreases
+			 * @taken_empty_lebs in 'ubifs_change_lp()', so it is
+			 * off by one for a short period of time which may
+			 * introduce a small disturbance to budgeting
+			 * calculations, but this is harmless because at the
+			 * worst case this would make the budgeting subsystem
+			 * be more pessimistic than needed.
+			 *
+			 * Fundamentally, this is about serialization of the
+			 * budgeting and lprops subsystems. We could make the
+			 * @space_lock a mutex and avoid dropping it before
+			 * calling 'ubifs_change_lp()', but mutex is more
+			 * heavy-weight, and we want budgeting to be as fast as
+			 * possible.
+			 */
+			c->lst.taken_empty_lebs += 1;
+		}
+	spin_unlock(&c->space_lock);
+
+	lprops = do_find_free_space(c, min_space, pick_free, squeeze);
+	if (IS_ERR(lprops)) {
+		err = PTR_ERR(lprops);
+		goto out;
+	}
+
+	lnum = lprops->lnum;
+	flags = lprops->flags | LPROPS_TAKEN;
+
+	lprops = ubifs_change_lp(c, lprops, LPROPS_NC, LPROPS_NC, flags, 0);
+	if (IS_ERR(lprops)) {
+		err = PTR_ERR(lprops);
+		goto out;
+	}
+
+	if (pick_free) {
+		spin_lock(&c->space_lock);
+		c->lst.taken_empty_lebs -= 1;
+		spin_unlock(&c->space_lock);
+	}
+
+	*free = lprops->free;
+	ubifs_release_lprops(c);
+
+	if (*free == c->leb_size) {
+		/*
+		 * Ensure that empty LEBs have been unmapped. They may not have
+		 * been, for example, because of an unclean unmount.  Also
+		 * LEBs that were freeable LEBs (free + dirty == leb_size) will
+		 * not have been unmapped.
+		 */
+		err = ubifs_leb_unmap(c, lnum);
+		if (err)
+			return err;
+	}
+
+	dbg_find("found LEB %d, free %d", lnum, *free);
+	ubifs_assert(*free >= min_space);
+	return lnum;
+
+out:
+	if (pick_free) {
+		spin_lock(&c->space_lock);
+		c->lst.taken_empty_lebs -= 1;
+		spin_unlock(&c->space_lock);
+	}
+	ubifs_release_lprops(c);
+	return err;
+}
+
+/**
+ * scan_for_idx_cb - callback used by the scan for a free LEB for the index.
+ * @c: the UBIFS file-system description object
+ * @lprops: LEB properties to scan
+ * @in_tree: whether the LEB properties are in main memory
+ * @data: information passed to and from the caller of the scan
+ *
+ * This function returns a code that indicates whether the scan should continue
+ * (%LPT_SCAN_CONTINUE), whether the LEB properties should be added to the tree
+ * in main memory (%LPT_SCAN_ADD), or whether the scan should stop
+ * (%LPT_SCAN_STOP).
+ */
+static int scan_for_idx_cb(struct ubifs_info *c,
+			   const struct ubifs_lprops *lprops, int in_tree,
+			   struct scan_data *data)
+{
+	int ret = LPT_SCAN_CONTINUE;
+
+	/* Exclude LEBs that are currently in use */
+	if (lprops->flags & LPROPS_TAKEN)
+		return LPT_SCAN_CONTINUE;
+	/* Determine whether to add these LEB properties to the tree */
+	if (!in_tree && valuable(c, lprops))
+		ret |= LPT_SCAN_ADD;
+	/* Exclude index LEBS */
+	if (lprops->flags & LPROPS_INDEX)
+		return ret;
+	/* Exclude LEBs that cannot be made empty */
+	if (lprops->free + lprops->dirty != c->leb_size)
+		return ret;
+	/*
+	 * We are allocating for the index so it is safe to allocate LEBs with
+	 * only free and dirty space, because write buffers are sync'd at commit
+	 * start.
+	 */
+	data->lnum = lprops->lnum;
+	return LPT_SCAN_ADD | LPT_SCAN_STOP;
+}
+
+/**
+ * scan_for_leb_for_idx - scan for a free LEB for the index.
+ * @c: the UBIFS file-system description object
+ */
+static const struct ubifs_lprops *scan_for_leb_for_idx(struct ubifs_info *c)
+{
+	struct ubifs_lprops *lprops;
+	struct scan_data data;
+	int err;
+
+	data.lnum = -1;
+	err = ubifs_lpt_scan_nolock(c, -1, c->lscan_lnum,
+				    (ubifs_lpt_scan_callback)scan_for_idx_cb,
+				    &data);
+	if (err)
+		return ERR_PTR(err);
+	ubifs_assert(data.lnum >= c->main_first && data.lnum < c->leb_cnt);
+	c->lscan_lnum = data.lnum;
+	lprops = ubifs_lpt_lookup_dirty(c, data.lnum);
+	if (IS_ERR(lprops))
+		return lprops;
+	ubifs_assert(lprops->lnum == data.lnum);
+	ubifs_assert(lprops->free + lprops->dirty == c->leb_size);
+	ubifs_assert(!(lprops->flags & LPROPS_TAKEN));
+	ubifs_assert(!(lprops->flags & LPROPS_INDEX));
+	return lprops;
+}
+
+/**
+ * ubifs_find_free_leb_for_idx - find a free LEB for the index.
+ * @c: the UBIFS file-system description object
+ *
+ * This function looks for a free LEB and returns that LEB number. The returned
+ * LEB is marked as "taken", "index".
+ *
+ * Only empty LEBs are allocated. This is for two reasons. First, the commit
+ * calculates the number of LEBs to allocate based on the assumption that they
+ * will be empty. Secondly, free space at the end of an index LEB is not
+ * guaranteed to be empty because it may have been used by the in-the-gaps
+ * method prior to an unclean unmount.
+ *
+ * If no LEB is found %-ENOSPC is returned. For other failures another negative
+ * error code is returned.
+ */
+int ubifs_find_free_leb_for_idx(struct ubifs_info *c)
+{
+	const struct ubifs_lprops *lprops;
+	int lnum = -1, err, flags;
+
+	ubifs_get_lprops(c);
+
+	lprops = ubifs_fast_find_empty(c);
+	if (!lprops) {
+		lprops = ubifs_fast_find_freeable(c);
+		if (!lprops) {
+			ubifs_assert(c->freeable_cnt == 0);
+			if (c->lst.empty_lebs - c->lst.taken_empty_lebs > 0) {
+				lprops = scan_for_leb_for_idx(c);
+				if (IS_ERR(lprops)) {
+					err = PTR_ERR(lprops);
+					goto out;
+				}
+			}
+		}
+	}
+
+	if (!lprops) {
+		err = -ENOSPC;
+		goto out;
+	}
+
+	lnum = lprops->lnum;
+
+	dbg_find("found LEB %d, free %d, dirty %d, flags %#x",
+		 lnum, lprops->free, lprops->dirty, lprops->flags);
+
+	flags = lprops->flags | LPROPS_TAKEN | LPROPS_INDEX;
+	lprops = ubifs_change_lp(c, lprops, c->leb_size, 0, flags, 0);
+	if (IS_ERR(lprops)) {
+		err = PTR_ERR(lprops);
+		goto out;
+	}
+
+	ubifs_release_lprops(c);
+
+	/*
+	 * Ensure that empty LEBs have been unmapped. They may not have been,
+	 * for example, because of an unclean unmount. Also LEBs that were
+	 * freeable LEBs (free + dirty == leb_size) will not have been unmapped.
+	 */
+	err = ubifs_leb_unmap(c, lnum);
+	if (err) {
+		ubifs_change_one_lp(c, lnum, LPROPS_NC, LPROPS_NC, 0,
+				    LPROPS_TAKEN | LPROPS_INDEX, 0);
+		return err;
+	}
+
+	return lnum;
+
+out:
+	ubifs_release_lprops(c);
+	return err;
+}
+
+static int cmp_dirty_idx(const struct ubifs_lprops **a,
+			 const struct ubifs_lprops **b)
+{
+	const struct ubifs_lprops *lpa = *a;
+	const struct ubifs_lprops *lpb = *b;
+
+	return lpa->dirty + lpa->free - lpb->dirty - lpb->free;
+}
+
+static void swap_dirty_idx(struct ubifs_lprops **a, struct ubifs_lprops **b,
+			   int size)
+{
+	struct ubifs_lprops *t = *a;
+
+	*a = *b;
+	*b = t;
+}
+
+/**
+ * ubifs_save_dirty_idx_lnums - save an array of the most dirty index LEB nos.
+ * @c: the UBIFS file-system description object
+ *
+ * This function is called each commit to create an array of LEB numbers of
+ * dirty index LEBs sorted in order of dirty and free space.  This is used by
+ * the in-the-gaps method of TNC commit.
+ */
+int ubifs_save_dirty_idx_lnums(struct ubifs_info *c)
+{
+	int i;
+
+	ubifs_get_lprops(c);
+	/* Copy the LPROPS_DIRTY_IDX heap */
+	c->dirty_idx.cnt = c->lpt_heap[LPROPS_DIRTY_IDX - 1].cnt;
+	memcpy(c->dirty_idx.arr, c->lpt_heap[LPROPS_DIRTY_IDX - 1].arr,
+	       sizeof(void *) * c->dirty_idx.cnt);
+	/* Sort it so that the dirtiest is now at the end */
+	sort(c->dirty_idx.arr, c->dirty_idx.cnt, sizeof(void *),
+	     (int (*)(const void *, const void *))cmp_dirty_idx,
+	     (void (*)(void *, void *, int))swap_dirty_idx);
+	dbg_find("found %d dirty index LEBs", c->dirty_idx.cnt);
+	if (c->dirty_idx.cnt)
+		dbg_find("dirtiest index LEB is %d with dirty %d and free %d",
+			 c->dirty_idx.arr[c->dirty_idx.cnt - 1]->lnum,
+			 c->dirty_idx.arr[c->dirty_idx.cnt - 1]->dirty,
+			 c->dirty_idx.arr[c->dirty_idx.cnt - 1]->free);
+	/* Replace the lprops pointers with LEB numbers */
+	for (i = 0; i < c->dirty_idx.cnt; i++)
+		c->dirty_idx.arr[i] = (void *)(size_t)c->dirty_idx.arr[i]->lnum;
+	ubifs_release_lprops(c);
+	return 0;
+}
+
+/**
+ * scan_dirty_idx_cb - callback used by the scan for a dirty index LEB.
+ * @c: the UBIFS file-system description object
+ * @lprops: LEB properties to scan
+ * @in_tree: whether the LEB properties are in main memory
+ * @data: information passed to and from the caller of the scan
+ *
+ * This function returns a code that indicates whether the scan should continue
+ * (%LPT_SCAN_CONTINUE), whether the LEB properties should be added to the tree
+ * in main memory (%LPT_SCAN_ADD), or whether the scan should stop
+ * (%LPT_SCAN_STOP).
+ */
+static int scan_dirty_idx_cb(struct ubifs_info *c,
+			   const struct ubifs_lprops *lprops, int in_tree,
+			   struct scan_data *data)
+{
+	int ret = LPT_SCAN_CONTINUE;
+
+	/* Exclude LEBs that are currently in use */
+	if (lprops->flags & LPROPS_TAKEN)
+		return LPT_SCAN_CONTINUE;
+	/* Determine whether to add these LEB properties to the tree */
+	if (!in_tree && valuable(c, lprops))
+		ret |= LPT_SCAN_ADD;
+	/* Exclude non-index LEBs */
+	if (!(lprops->flags & LPROPS_INDEX))
+		return ret;
+	/* Exclude LEBs with too little space */
+	if (lprops->free + lprops->dirty < c->min_idx_node_sz)
+		return ret;
+	/* Finally we found space */
+	data->lnum = lprops->lnum;
+	return LPT_SCAN_ADD | LPT_SCAN_STOP;
+}
+
+/**
+ * find_dirty_idx_leb - find a dirty index LEB.
+ * @c: the UBIFS file-system description object
+ *
+ * This function returns LEB number upon success and a negative error code upon
+ * failure.  In particular, -ENOSPC is returned if a dirty index LEB is not
+ * found.
+ *
+ * Note that this function scans the entire LPT but it is called very rarely.
+ */
+static int find_dirty_idx_leb(struct ubifs_info *c)
+{
+	const struct ubifs_lprops *lprops;
+	struct ubifs_lpt_heap *heap;
+	struct scan_data data;
+	int err, i, ret;
+
+	/* Check all structures in memory first */
+	data.lnum = -1;
+	heap = &c->lpt_heap[LPROPS_DIRTY_IDX - 1];
+	for (i = 0; i < heap->cnt; i++) {
+		lprops = heap->arr[i];
+		ret = scan_dirty_idx_cb(c, lprops, 1, &data);
+		if (ret & LPT_SCAN_STOP)
+			goto found;
+	}
+	list_for_each_entry(lprops, &c->frdi_idx_list, list) {
+		ret = scan_dirty_idx_cb(c, lprops, 1, &data);
+		if (ret & LPT_SCAN_STOP)
+			goto found;
+	}
+	list_for_each_entry(lprops, &c->uncat_list, list) {
+		ret = scan_dirty_idx_cb(c, lprops, 1, &data);
+		if (ret & LPT_SCAN_STOP)
+			goto found;
+	}
+	if (c->pnodes_have >= c->pnode_cnt)
+		/* All pnodes are in memory, so skip scan */
+		return -ENOSPC;
+	err = ubifs_lpt_scan_nolock(c, -1, c->lscan_lnum,
+				    (ubifs_lpt_scan_callback)scan_dirty_idx_cb,
+				    &data);
+	if (err)
+		return err;
+found:
+	ubifs_assert(data.lnum >= c->main_first && data.lnum < c->leb_cnt);
+	c->lscan_lnum = data.lnum;
+	lprops = ubifs_lpt_lookup_dirty(c, data.lnum);
+	if (IS_ERR(lprops))
+		return PTR_ERR(lprops);
+	ubifs_assert(lprops->lnum == data.lnum);
+	ubifs_assert(lprops->free + lprops->dirty >= c->min_idx_node_sz);
+	ubifs_assert(!(lprops->flags & LPROPS_TAKEN));
+	ubifs_assert((lprops->flags & LPROPS_INDEX));
+
+	dbg_find("found dirty LEB %d, free %d, dirty %d, flags %#x",
+		 lprops->lnum, lprops->free, lprops->dirty, lprops->flags);
+
+	lprops = ubifs_change_lp(c, lprops, LPROPS_NC, LPROPS_NC,
+				 lprops->flags | LPROPS_TAKEN, 0);
+	if (IS_ERR(lprops))
+		return PTR_ERR(lprops);
+
+	return lprops->lnum;
+}
+
+/**
+ * get_idx_gc_leb - try to get a LEB number from trivial GC.
+ * @c: the UBIFS file-system description object
+ */
+static int get_idx_gc_leb(struct ubifs_info *c)
+{
+	const struct ubifs_lprops *lp;
+	int err, lnum;
+
+	err = ubifs_get_idx_gc_leb(c);
+	if (err < 0)
+		return err;
+	lnum = err;
+	/*
+	 * The LEB was due to be unmapped after the commit but
+	 * it is needed now for this commit.
+	 */
+	lp = ubifs_lpt_lookup_dirty(c, lnum);
+	if (unlikely(IS_ERR(lp)))
+		return PTR_ERR(lp);
+	lp = ubifs_change_lp(c, lp, LPROPS_NC, LPROPS_NC,
+			     lp->flags | LPROPS_INDEX, -1);
+	if (unlikely(IS_ERR(lp)))
+		return PTR_ERR(lp);
+	dbg_find("LEB %d, dirty %d and free %d flags %#x",
+		 lp->lnum, lp->dirty, lp->free, lp->flags);
+	return lnum;
+}
+
+/**
+ * find_dirtiest_idx_leb - find dirtiest index LEB from dirtiest array.
+ * @c: the UBIFS file-system description object
+ */
+static int find_dirtiest_idx_leb(struct ubifs_info *c)
+{
+	const struct ubifs_lprops *lp;
+	int lnum;
+
+	while (1) {
+		if (!c->dirty_idx.cnt)
+			return -ENOSPC;
+		/* The lprops pointers were replaced by LEB numbers */
+		lnum = (size_t)c->dirty_idx.arr[--c->dirty_idx.cnt];
+		lp = ubifs_lpt_lookup(c, lnum);
+		if (IS_ERR(lp))
+			return PTR_ERR(lp);
+		if ((lp->flags & LPROPS_TAKEN) || !(lp->flags & LPROPS_INDEX))
+			continue;
+		lp = ubifs_change_lp(c, lp, LPROPS_NC, LPROPS_NC,
+				     lp->flags | LPROPS_TAKEN, 0);
+		if (IS_ERR(lp))
+			return PTR_ERR(lp);
+		break;
+	}
+	dbg_find("LEB %d, dirty %d and free %d flags %#x", lp->lnum, lp->dirty,
+		 lp->free, lp->flags);
+	ubifs_assert(lp->flags | LPROPS_TAKEN);
+	ubifs_assert(lp->flags | LPROPS_INDEX);
+	return lnum;
+}
+
+/**
+ * ubifs_find_dirty_idx_leb - try to find dirtiest index LEB as at last commit.
+ * @c: the UBIFS file-system description object
+ *
+ * This function attempts to find an untaken index LEB with the most free and
+ * dirty space that can be used without overwriting index nodes that were in the
+ * last index committed.
+ */
+int ubifs_find_dirty_idx_leb(struct ubifs_info *c)
+{
+	int err;
+
+	ubifs_get_lprops(c);
+
+	/*
+	 * We made an array of the dirtiest index LEB numbers as at the start of
+	 * last commit.  Try that array first.
+	 */
+	err = find_dirtiest_idx_leb(c);
+
+	/* Next try scanning the entire LPT */
+	if (err == -ENOSPC)
+		err = find_dirty_idx_leb(c);
+
+	/* Finally take any index LEBs awaiting trivial GC */
+	if (err == -ENOSPC)
+		err = get_idx_gc_leb(c);
+
+	ubifs_release_lprops(c);
+	return err;
+}
diff --git a/fs/ubifs/gc.c b/fs/ubifs/gc.c
new file mode 100644
index 00000000000..d0f3dac2908
--- /dev/null
+++ b/fs/ubifs/gc.c
@@ -0,0 +1,773 @@
+/*
+ * This file is part of UBIFS.
+ *
+ * Copyright (C) 2006-2008 Nokia Corporation.
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 as published by
+ * the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
+ * more details.
+ *
+ * You should have received a copy of the GNU General Public License along with
+ * this program; if not, write to the Free Software Foundation, Inc., 51
+ * Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
+ *
+ * Authors: Adrian Hunter
+ *          Artem Bityutskiy (Битюцкий Артём)
+ */
+
+/*
+ * This file implements garbage collection. The procedure for garbage collection
+ * is different depending on whether a LEB as an index LEB (contains index
+ * nodes) or not. For non-index LEBs, garbage collection finds a LEB which
+ * contains a lot of dirty space (obsolete nodes), and copies the non-obsolete
+ * nodes to the journal, at which point the garbage-collected LEB is free to be
+ * reused. For index LEBs, garbage collection marks the non-obsolete index nodes
+ * dirty in the TNC, and after the next commit, the garbage-collected LEB is
+ * to be reused. Garbage collection will cause the number of dirty index nodes
+ * to grow, however sufficient space is reserved for the index to ensure the
+ * commit will never run out of space.
+ */
+
+#include <linux/pagemap.h>
+#include "ubifs.h"
+
+/*
+ * GC tries to optimize the way it fit nodes to available space, and it sorts
+ * nodes a little. The below constants are watermarks which define "large",
+ * "medium", and "small" nodes.
+ */
+#define MEDIUM_NODE_WM (UBIFS_BLOCK_SIZE / 4)
+#define SMALL_NODE_WM  UBIFS_MAX_DENT_NODE_SZ
+
+/*
+ * GC may need to move more then one LEB to make progress. The below constants
+ * define "soft" and "hard" limits on the number of LEBs the garbage collector
+ * may move.
+ */
+#define SOFT_LEBS_LIMIT 4
+#define HARD_LEBS_LIMIT 32
+
+/**
+ * switch_gc_head - switch the garbage collection journal head.
+ * @c: UBIFS file-system description object
+ * @buf: buffer to write
+ * @len: length of the buffer to write
+ * @lnum: LEB number written is returned here
+ * @offs: offset written is returned here
+ *
+ * This function switch the GC head to the next LEB which is reserved in
+ * @c->gc_lnum. Returns %0 in case of success, %-EAGAIN if commit is required,
+ * and other negative error code in case of failures.
+ */
+static int switch_gc_head(struct ubifs_info *c)
+{
+	int err, gc_lnum = c->gc_lnum;
+	struct ubifs_wbuf *wbuf = &c->jheads[GCHD].wbuf;
+
+	ubifs_assert(gc_lnum != -1);
+	dbg_gc("switch GC head from LEB %d:%d to LEB %d (waste %d bytes)",
+	       wbuf->lnum, wbuf->offs + wbuf->used, gc_lnum,
+	       c->leb_size - wbuf->offs - wbuf->used);
+
+	err = ubifs_wbuf_sync_nolock(wbuf);
+	if (err)
+		return err;
+
+	/*
+	 * The GC write-buffer was synchronized, we may safely unmap
+	 * 'c->gc_lnum'.
+	 */
+	err = ubifs_leb_unmap(c, gc_lnum);
+	if (err)
+		return err;
+
+	err = ubifs_add_bud_to_log(c, GCHD, gc_lnum, 0);
+	if (err)
+		return err;
+
+	c->gc_lnum = -1;
+	err = ubifs_wbuf_seek_nolock(wbuf, gc_lnum, 0, UBI_LONGTERM);
+	return err;
+}
+
+/**
+ * move_nodes - move nodes.
+ * @c: UBIFS file-system description object
+ * @sleb: describes nodes to move
+ *
+ * This function moves valid nodes from data LEB described by @sleb to the GC
+ * journal head. The obsolete nodes are dropped.
+ *
+ * When moving nodes we have to deal with classical bin-packing problem: the
+ * space in the current GC journal head LEB and in @c->gc_lnum are the "bins",
+ * where the nodes in the @sleb->nodes list are the elements which should be
+ * fit optimally to the bins. This function uses the "first fit decreasing"
+ * strategy, although it does not really sort the nodes but just split them on
+ * 3 classes - large, medium, and small, so they are roughly sorted.
+ *
+ * This function returns zero in case of success, %-EAGAIN if commit is
+ * required, and other negative error codes in case of other failures.
+ */
+static int move_nodes(struct ubifs_info *c, struct ubifs_scan_leb *sleb)
+{
+	struct ubifs_scan_node *snod, *tmp;
+	struct list_head large, medium, small;
+	struct ubifs_wbuf *wbuf = &c->jheads[GCHD].wbuf;
+	int avail, err, min = INT_MAX;
+
+	INIT_LIST_HEAD(&large);
+	INIT_LIST_HEAD(&medium);
+	INIT_LIST_HEAD(&small);
+
+	list_for_each_entry_safe(snod, tmp, &sleb->nodes, list) {
+		struct list_head *lst;
+
+		ubifs_assert(snod->type != UBIFS_IDX_NODE);
+		ubifs_assert(snod->type != UBIFS_REF_NODE);
+		ubifs_assert(snod->type != UBIFS_CS_NODE);
+
+		err = ubifs_tnc_has_node(c, &snod->key, 0, sleb->lnum,
+					 snod->offs, 0);
+		if (err < 0)
+			goto out;
+
+		lst = &snod->list;
+		list_del(lst);
+		if (!err) {
+			/* The node is obsolete, remove it from the list */
+			kfree(snod);
+			continue;
+		}
+
+		/*
+		 * Sort the list of nodes so that large nodes go first, and
+		 * small nodes go last.
+		 */
+		if (snod->len > MEDIUM_NODE_WM)
+			list_add(lst, &large);
+		else if (snod->len > SMALL_NODE_WM)
+			list_add(lst, &medium);
+		else
+			list_add(lst, &small);
+
+		/* And find the smallest node */
+		if (snod->len < min)
+			min = snod->len;
+	}
+
+	/*
+	 * Join the tree lists so that we'd have one roughly sorted list
+	 * ('large' will be the head of the joined list).
+	 */
+	list_splice(&medium, large.prev);
+	list_splice(&small, large.prev);
+
+	if (wbuf->lnum == -1) {
+		/*
+		 * The GC journal head is not set, because it is the first GC
+		 * invocation since mount.
+		 */
+		err = switch_gc_head(c);
+		if (err)
+			goto out;
+	}
+
+	/* Write nodes to their new location. Use the first-fit strategy */
+	while (1) {
+		avail = c->leb_size - wbuf->offs - wbuf->used;
+		list_for_each_entry_safe(snod, tmp, &large, list) {
+			int new_lnum, new_offs;
+
+			if (avail < min)
+				break;
+
+			if (snod->len > avail)
+				/* This node does not fit */
+				continue;
+
+			cond_resched();
+
+			new_lnum = wbuf->lnum;
+			new_offs = wbuf->offs + wbuf->used;
+			err = ubifs_wbuf_write_nolock(wbuf, snod->node,
+						      snod->len);
+			if (err)
+				goto out;
+			err = ubifs_tnc_replace(c, &snod->key, sleb->lnum,
+						snod->offs, new_lnum, new_offs,
+						snod->len);
+			if (err)
+				goto out;
+
+			avail = c->leb_size - wbuf->offs - wbuf->used;
+			list_del(&snod->list);
+			kfree(snod);
+		}
+
+		if (list_empty(&large))
+			break;
+
+		/*
+		 * Waste the rest of the space in the LEB and switch to the
+		 * next LEB.
+		 */
+		err = switch_gc_head(c);
+		if (err)
+			goto out;
+	}
+
+	return 0;
+
+out:
+	list_for_each_entry_safe(snod, tmp, &large, list) {
+		list_del(&snod->list);
+		kfree(snod);
+	}
+	return err;
+}
+
+/**
+ * gc_sync_wbufs - sync write-buffers for GC.
+ * @c: UBIFS file-system description object
+ *
+ * We must guarantee that obsoleting nodes are on flash. Unfortunately they may
+ * be in a write-buffer instead. That is, a node could be written to a
+ * write-buffer, obsoleting another node in a LEB that is GC'd. If that LEB is
+ * erased before the write-buffer is sync'd and then there is an unclean
+ * unmount, then an existing node is lost. To avoid this, we sync all
+ * write-buffers.
+ *
+ * This function returns %0 on success or a negative error code on failure.
+ */
+static int gc_sync_wbufs(struct ubifs_info *c)
+{
+	int err, i;
+
+	for (i = 0; i < c->jhead_cnt; i++) {
+		if (i == GCHD)
+			continue;
+		err = ubifs_wbuf_sync(&c->jheads[i].wbuf);
+		if (err)
+			return err;
+	}
+	return 0;
+}
+
+/**
+ * ubifs_garbage_collect_leb - garbage-collect a logical eraseblock.
+ * @c: UBIFS file-system description object
+ * @lp: describes the LEB to garbage collect
+ *
+ * This function garbage-collects an LEB and returns one of the @LEB_FREED,
+ * @LEB_RETAINED, etc positive codes in case of success, %-EAGAIN if commit is
+ * required, and other negative error codes in case of failures.
+ */
+int ubifs_garbage_collect_leb(struct ubifs_info *c, struct ubifs_lprops *lp)
+{
+	struct ubifs_scan_leb *sleb;
+	struct ubifs_scan_node *snod;
+	struct ubifs_wbuf *wbuf = &c->jheads[GCHD].wbuf;
+	int err = 0, lnum = lp->lnum;
+
+	ubifs_assert(c->gc_lnum != -1 || wbuf->offs + wbuf->used == 0 ||
+		     c->need_recovery);
+	ubifs_assert(c->gc_lnum != lnum);
+	ubifs_assert(wbuf->lnum != lnum);
+
+	/*
+	 * We scan the entire LEB even though we only really need to scan up to
+	 * (c->leb_size - lp->free).
+	 */
+	sleb = ubifs_scan(c, lnum, 0, c->sbuf);
+	if (IS_ERR(sleb))
+		return PTR_ERR(sleb);
+
+	ubifs_assert(!list_empty(&sleb->nodes));
+	snod = list_entry(sleb->nodes.next, struct ubifs_scan_node, list);
+
+	if (snod->type == UBIFS_IDX_NODE) {
+		struct ubifs_gced_idx_leb *idx_gc;
+
+		dbg_gc("indexing LEB %d (free %d, dirty %d)",
+		       lnum, lp->free, lp->dirty);
+		list_for_each_entry(snod, &sleb->nodes, list) {
+			struct ubifs_idx_node *idx = snod->node;
+			int level = le16_to_cpu(idx->level);
+
+			ubifs_assert(snod->type == UBIFS_IDX_NODE);
+			key_read(c, ubifs_idx_key(c, idx), &snod->key);
+			err = ubifs_dirty_idx_node(c, &snod->key, level, lnum,
+						   snod->offs);
+			if (err)
+				goto out;
+		}
+
+		idx_gc = kmalloc(sizeof(struct ubifs_gced_idx_leb), GFP_NOFS);
+		if (!idx_gc) {
+			err = -ENOMEM;
+			goto out;
+		}
+
+		idx_gc->lnum = lnum;
+		idx_gc->unmap = 0;
+		list_add(&idx_gc->list, &c->idx_gc);
+
+		/*
+		 * Don't release the LEB until after the next commit, because
+		 * it may contain date which is needed for recovery. So
+		 * although we freed this LEB, it will become usable only after
+		 * the commit.
+		 */
+		err = ubifs_change_one_lp(c, lnum, c->leb_size, 0, 0,
+					  LPROPS_INDEX, 1);
+		if (err)
+			goto out;
+		err = LEB_FREED_IDX;
+	} else {
+		dbg_gc("data LEB %d (free %d, dirty %d)",
+		       lnum, lp->free, lp->dirty);
+
+		err = move_nodes(c, sleb);
+		if (err)
+			goto out;
+
+		err = gc_sync_wbufs(c);
+		if (err)
+			goto out;
+
+		err = ubifs_change_one_lp(c, lnum, c->leb_size, 0, 0, 0, 0);
+		if (err)
+			goto out;
+
+		if (c->gc_lnum == -1) {
+			c->gc_lnum = lnum;
+			err = LEB_RETAINED;
+		} else {
+			err = ubifs_wbuf_sync_nolock(wbuf);
+			if (err)
+				goto out;
+
+			err = ubifs_leb_unmap(c, lnum);
+			if (err)
+				goto out;
+
+			err = LEB_FREED;
+		}
+	}
+
+out:
+	ubifs_scan_destroy(sleb);
+	return err;
+}
+
+/**
+ * ubifs_garbage_collect - UBIFS garbage collector.
+ * @c: UBIFS file-system description object
+ * @anyway: do GC even if there are free LEBs
+ *
+ * This function does out-of-place garbage collection. The return codes are:
+ *   o positive LEB number if the LEB has been freed and may be used;
+ *   o %-EAGAIN if the caller has to run commit;
+ *   o %-ENOSPC if GC failed to make any progress;
+ *   o other negative error codes in case of other errors.
+ *
+ * Garbage collector writes data to the journal when GC'ing data LEBs, and just
+ * marking indexing nodes dirty when GC'ing indexing LEBs. Thus, at some point
+ * commit may be required. But commit cannot be run from inside GC, because the
+ * caller might be holding the commit lock, so %-EAGAIN is returned instead;
+ * And this error code means that the caller has to run commit, and re-run GC
+ * if there is still no free space.
+ *
+ * There are many reasons why this function may return %-EAGAIN:
+ * o the log is full and there is no space to write an LEB reference for
+ *   @c->gc_lnum;
+ * o the journal is too large and exceeds size limitations;
+ * o GC moved indexing LEBs, but they can be used only after the commit;
+ * o the shrinker fails to find clean znodes to free and requests the commit;
+ * o etc.
+ *
+ * Note, if the file-system is close to be full, this function may return
+ * %-EAGAIN infinitely, so the caller has to limit amount of re-invocations of
+ * the function. E.g., this happens if the limits on the journal size are too
+ * tough and GC writes too much to the journal before an LEB is freed. This
+ * might also mean that the journal is too large, and the TNC becomes to big,
+ * so that the shrinker is constantly called, finds not clean znodes to free,
+ * and requests commit. Well, this may also happen if the journal is all right,
+ * but another kernel process consumes too much memory. Anyway, infinite
+ * %-EAGAIN may happen, but in some extreme/misconfiguration cases.
+ */
+int ubifs_garbage_collect(struct ubifs_info *c, int anyway)
+{
+	int i, err, ret, min_space = c->dead_wm;
+	struct ubifs_lprops lp;
+	struct ubifs_wbuf *wbuf = &c->jheads[GCHD].wbuf;
+
+	ubifs_assert_cmt_locked(c);
+
+	if (ubifs_gc_should_commit(c))
+		return -EAGAIN;
+
+	mutex_lock_nested(&wbuf->io_mutex, wbuf->jhead);
+
+	if (c->ro_media) {
+		ret = -EROFS;
+		goto out_unlock;
+	}
+
+	/* We expect the write-buffer to be empty on entry */
+	ubifs_assert(!wbuf->used);
+
+	for (i = 0; ; i++) {
+		int space_before = c->leb_size - wbuf->offs - wbuf->used;
+		int space_after;
+
+		cond_resched();
+
+		/* Give the commit an opportunity to run */
+		if (ubifs_gc_should_commit(c)) {
+			ret = -EAGAIN;
+			break;
+		}
+
+		if (i > SOFT_LEBS_LIMIT && !list_empty(&c->idx_gc)) {
+			/*
+			 * We've done enough iterations. Indexing LEBs were
+			 * moved and will be available after the commit.
+			 */
+			dbg_gc("soft limit, some index LEBs GC'ed, -EAGAIN");
+			ubifs_commit_required(c);
+			ret = -EAGAIN;
+			break;
+		}
+
+		if (i > HARD_LEBS_LIMIT) {
+			/*
+			 * We've moved too many LEBs and have not made
+			 * progress, give up.
+			 */
+			dbg_gc("hard limit, -ENOSPC");
+			ret = -ENOSPC;
+			break;
+		}
+
+		/*
+		 * Empty and freeable LEBs can turn up while we waited for
+		 * the wbuf lock, or while we have been running GC. In that
+		 * case, we should just return one of those instead of
+		 * continuing to GC dirty LEBs. Hence we request
+		 * 'ubifs_find_dirty_leb()' to return an empty LEB if it can.
+		 */
+		ret = ubifs_find_dirty_leb(c, &lp, min_space, anyway ? 0 : 1);
+		if (ret) {
+			if (ret == -ENOSPC)
+				dbg_gc("no more dirty LEBs");
+			break;
+		}
+
+		dbg_gc("found LEB %d: free %d, dirty %d, sum %d "
+		       "(min. space %d)", lp.lnum, lp.free, lp.dirty,
+		       lp.free + lp.dirty, min_space);
+
+		if (lp.free + lp.dirty == c->leb_size) {
+			/* An empty LEB was returned */
+			dbg_gc("LEB %d is free, return it", lp.lnum);
+			/*
+			 * ubifs_find_dirty_leb() doesn't return freeable index
+			 * LEBs.
+			 */
+			ubifs_assert(!(lp.flags & LPROPS_INDEX));
+			if (lp.free != c->leb_size) {
+				/*
+				 * Write buffers must be sync'd before
+				 * unmapping freeable LEBs, because one of them
+				 * may contain data which obsoletes something
+				 * in 'lp.pnum'.
+				 */
+				ret = gc_sync_wbufs(c);
+				if (ret)
+					goto out;
+				ret = ubifs_change_one_lp(c, lp.lnum,
+							  c->leb_size, 0, 0, 0,
+							  0);
+				if (ret)
+					goto out;
+			}
+			ret = ubifs_leb_unmap(c, lp.lnum);
+			if (ret)
+				goto out;
+			ret = lp.lnum;
+			break;
+		}
+
+		space_before = c->leb_size - wbuf->offs - wbuf->used;
+		if (wbuf->lnum == -1)
+			space_before = 0;
+
+		ret = ubifs_garbage_collect_leb(c, &lp);
+		if (ret < 0) {
+			if (ret == -EAGAIN || ret == -ENOSPC) {
+				/*
+				 * These codes are not errors, so we have to
+				 * return the LEB to lprops. But if the
+				 * 'ubifs_return_leb()' function fails, its
+				 * failure code is propagated to the caller
+				 * instead of the original '-EAGAIN' or
+				 * '-ENOSPC'.
+				 */
+				err = ubifs_return_leb(c, lp.lnum);
+				if (err)
+					ret = err;
+				break;
+			}
+			goto out;
+		}
+
+		if (ret == LEB_FREED) {
+			/* An LEB has been freed and is ready for use */
+			dbg_gc("LEB %d freed, return", lp.lnum);
+			ret = lp.lnum;
+			break;
+		}
+
+		if (ret == LEB_FREED_IDX) {
+			/*
+			 * This was an indexing LEB and it cannot be
+			 * immediately used. And instead of requesting the
+			 * commit straight away, we try to garbage collect some
+			 * more.
+			 */
+			dbg_gc("indexing LEB %d freed, continue", lp.lnum);
+			continue;
+		}
+
+		ubifs_assert(ret == LEB_RETAINED);
+		space_after = c->leb_size - wbuf->offs - wbuf->used;
+		dbg_gc("LEB %d retained, freed %d bytes", lp.lnum,
+		       space_after - space_before);
+
+		if (space_after > space_before) {
+			/* GC makes progress, keep working */
+			min_space >>= 1;
+			if (min_space < c->dead_wm)
+				min_space = c->dead_wm;
+			continue;
+		}
+
+		dbg_gc("did not make progress");
+
+		/*
+		 * GC moved an LEB bud have not done any progress. This means
+		 * that the previous GC head LEB contained too few free space
+		 * and the LEB which was GC'ed contained only large nodes which
+		 * did not fit that space.
+		 *
+		 * We can do 2 things:
+		 * 1. pick another LEB in a hope it'll contain a small node
+		 *    which will fit the space we have at the end of current GC
+		 *    head LEB, but there is no guarantee, so we try this out
+		 *    unless we have already been working for too long;
+		 * 2. request an LEB with more dirty space, which will force
+		 *    'ubifs_find_dirty_leb()' to start scanning the lprops
+		 *    table, instead of just picking one from the heap
+		 *    (previously it already picked the dirtiest LEB).
+		 */
+		if (i < SOFT_LEBS_LIMIT) {
+			dbg_gc("try again");
+			continue;
+		}
+
+		min_space <<= 1;
+		if (min_space > c->dark_wm)
+			min_space = c->dark_wm;
+		dbg_gc("set min. space to %d", min_space);
+	}
+
+	if (ret == -ENOSPC && !list_empty(&c->idx_gc)) {
+		dbg_gc("no space, some index LEBs GC'ed, -EAGAIN");
+		ubifs_commit_required(c);
+		ret = -EAGAIN;
+	}
+
+	err = ubifs_wbuf_sync_nolock(wbuf);
+	if (!err)
+		err = ubifs_leb_unmap(c, c->gc_lnum);
+	if (err) {
+		ret = err;
+		goto out;
+	}
+out_unlock:
+	mutex_unlock(&wbuf->io_mutex);
+	return ret;
+
+out:
+	ubifs_assert(ret < 0);
+	ubifs_assert(ret != -ENOSPC && ret != -EAGAIN);
+	ubifs_ro_mode(c, ret);
+	ubifs_wbuf_sync_nolock(wbuf);
+	mutex_unlock(&wbuf->io_mutex);
+	ubifs_return_leb(c, lp.lnum);
+	return ret;
+}
+
+/**
+ * ubifs_gc_start_commit - garbage collection at start of commit.
+ * @c: UBIFS file-system description object
+ *
+ * If a LEB has only dirty and free space, then we may safely unmap it and make
+ * it free.  Note, we cannot do this with indexing LEBs because dirty space may
+ * correspond index nodes that are required for recovery.  In that case, the
+ * LEB cannot be unmapped until after the next commit.
+ *
+ * This function returns %0 upon success and a negative error code upon failure.
+ */
+int ubifs_gc_start_commit(struct ubifs_info *c)
+{
+	struct ubifs_gced_idx_leb *idx_gc;
+	const struct ubifs_lprops *lp;
+	int err = 0, flags;
+
+	ubifs_get_lprops(c);
+
+	/*
+	 * Unmap (non-index) freeable LEBs. Note that recovery requires that all
+	 * wbufs are sync'd before this, which is done in 'do_commit()'.
+	 */
+	while (1) {
+		lp = ubifs_fast_find_freeable(c);
+		if (unlikely(IS_ERR(lp))) {
+			err = PTR_ERR(lp);
+			goto out;
+		}
+		if (!lp)
+			break;
+		ubifs_assert(!(lp->flags & LPROPS_TAKEN));
+		ubifs_assert(!(lp->flags & LPROPS_INDEX));
+		err = ubifs_leb_unmap(c, lp->lnum);
+		if (err)
+			goto out;
+		lp = ubifs_change_lp(c, lp, c->leb_size, 0, lp->flags, 0);
+		if (unlikely(IS_ERR(lp))) {
+			err = PTR_ERR(lp);
+			goto out;
+		}
+		ubifs_assert(!(lp->flags & LPROPS_TAKEN));
+		ubifs_assert(!(lp->flags & LPROPS_INDEX));
+	}
+
+	/* Mark GC'd index LEBs OK to unmap after this commit finishes */
+	list_for_each_entry(idx_gc, &c->idx_gc, list)
+		idx_gc->unmap = 1;
+
+	/* Record index freeable LEBs for unmapping after commit */
+	while (1) {
+		lp = ubifs_fast_find_frdi_idx(c);
+		if (unlikely(IS_ERR(lp))) {
+			err = PTR_ERR(lp);
+			goto out;
+		}
+		if (!lp)
+			break;
+		idx_gc = kmalloc(sizeof(struct ubifs_gced_idx_leb), GFP_NOFS);
+		if (!idx_gc) {
+			err = -ENOMEM;
+			goto out;
+		}
+		ubifs_assert(!(lp->flags & LPROPS_TAKEN));
+		ubifs_assert(lp->flags & LPROPS_INDEX);
+		/* Don't release the LEB until after the next commit */
+		flags = (lp->flags | LPROPS_TAKEN) ^ LPROPS_INDEX;
+		lp = ubifs_change_lp(c, lp, c->leb_size, 0, flags, 1);
+		if (unlikely(IS_ERR(lp))) {
+			err = PTR_ERR(lp);
+			kfree(idx_gc);
+			goto out;
+		}
+		ubifs_assert(lp->flags & LPROPS_TAKEN);
+		ubifs_assert(!(lp->flags & LPROPS_INDEX));
+		idx_gc->lnum = lp->lnum;
+		idx_gc->unmap = 1;
+		list_add(&idx_gc->list, &c->idx_gc);
+	}
+out:
+	ubifs_release_lprops(c);
+	return err;
+}
+
+/**
+ * ubifs_gc_end_commit - garbage collection at end of commit.
+ * @c: UBIFS file-system description object
+ *
+ * This function completes out-of-place garbage collection of index LEBs.
+ */
+int ubifs_gc_end_commit(struct ubifs_info *c)
+{
+	struct ubifs_gced_idx_leb *idx_gc, *tmp;
+	struct ubifs_wbuf *wbuf;
+	int err = 0;
+
+	wbuf = &c->jheads[GCHD].wbuf;
+	mutex_lock_nested(&wbuf->io_mutex, wbuf->jhead);
+	list_for_each_entry_safe(idx_gc, tmp, &c->idx_gc, list)
+		if (idx_gc->unmap) {
+			dbg_gc("LEB %d", idx_gc->lnum);
+			err = ubifs_leb_unmap(c, idx_gc->lnum);
+			if (err)
+				goto out;
+			err = ubifs_change_one_lp(c, idx_gc->lnum, LPROPS_NC,
+					  LPROPS_NC, 0, LPROPS_TAKEN, -1);
+			if (err)
+				goto out;
+			list_del(&idx_gc->list);
+			kfree(idx_gc);
+		}
+out:
+	mutex_unlock(&wbuf->io_mutex);
+	return err;
+}
+
+/**
+ * ubifs_destroy_idx_gc - destroy idx_gc list.
+ * @c: UBIFS file-system description object
+ *
+ * This function destroys the idx_gc list. It is called when unmounting or
+ * remounting read-only so locks are not needed.
+ */
+void ubifs_destroy_idx_gc(struct ubifs_info *c)
+{
+	while (!list_empty(&c->idx_gc)) {
+		struct ubifs_gced_idx_leb *idx_gc;
+
+		idx_gc = list_entry(c->idx_gc.next, struct ubifs_gced_idx_leb,
+				    list);
+		c->idx_gc_cnt -= 1;
+		list_del(&idx_gc->list);
+		kfree(idx_gc);
+	}
+
+}
+
+/**
+ * ubifs_get_idx_gc_leb - get a LEB from GC'd index LEB list.
+ * @c: UBIFS file-system description object
+ *
+ * Called during start commit so locks are not needed.
+ */
+int ubifs_get_idx_gc_leb(struct ubifs_info *c)
+{
+	struct ubifs_gced_idx_leb *idx_gc;
+	int lnum;
+
+	if (list_empty(&c->idx_gc))
+		return -ENOSPC;
+	idx_gc = list_entry(c->idx_gc.next, struct ubifs_gced_idx_leb, list);
+	lnum = idx_gc->lnum;
+	/* c->idx_gc_cnt is updated by the caller when lprops are updated */
+	list_del(&idx_gc->list);
+	kfree(idx_gc);
+	return lnum;
+}
diff --git a/fs/ubifs/io.c b/fs/ubifs/io.c
new file mode 100644
index 00000000000..3374f91b670
--- /dev/null
+++ b/fs/ubifs/io.c
@@ -0,0 +1,914 @@
+/*
+ * This file is part of UBIFS.
+ *
+ * Copyright (C) 2006-2008 Nokia Corporation.
+ * Copyright (C) 2006, 2007 University of Szeged, Hungary
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 as published by
+ * the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
+ * more details.
+ *
+ * You should have received a copy of the GNU General Public License along with
+ * this program; if not, write to the Free Software Foundation, Inc., 51
+ * Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
+ *
+ * Authors: Artem Bityutskiy (Битюцкий Артём)
+ *          Adrian Hunter
+ *          Zoltan Sogor
+ */
+
+/*
+ * This file implements UBIFS I/O subsystem which provides various I/O-related
+ * helper functions (reading/writing/checking/validating nodes) and implements
+ * write-buffering support. Write buffers help to save space which otherwise
+ * would have been wasted for padding to the nearest minimal I/O unit boundary.
+ * Instead, data first goes to the write-buffer and is flushed when the
+ * buffer is full or when it is not used for some time (by timer). This is
+ * similarto the mechanism is used by JFFS2.
+ *
+ * Write-buffers are defined by 'struct ubifs_wbuf' objects and protected by
+ * mutexes defined inside these objects. Since sometimes upper-level code
+ * has to lock the write-buffer (e.g. journal space reservation code), many
+ * functions related to write-buffers have "nolock" suffix which means that the
+ * caller has to lock the write-buffer before calling this function.
+ *
+ * UBIFS stores nodes at 64 bit-aligned addresses. If the node length is not
+ * aligned, UBIFS starts the next node from the aligned address, and the padded
+ * bytes may contain any rubbish. In other words, UBIFS does not put padding
+ * bytes in those small gaps. Common headers of nodes store real node lengths,
+ * not aligned lengths. Indexing nodes also store real lengths in branches.
+ *
+ * UBIFS uses padding when it pads to the next min. I/O unit. In this case it
+ * uses padding nodes or padding bytes, if the padding node does not fit.
+ *
+ * All UBIFS nodes are protected by CRC checksums and UBIFS checks all nodes
+ * every time they are read from the flash media.
+ */
+
+#include <linux/crc32.h>
+#include "ubifs.h"
+
+/**
+ * ubifs_check_node - check node.
+ * @c: UBIFS file-system description object
+ * @buf: node to check
+ * @lnum: logical eraseblock number
+ * @offs: offset within the logical eraseblock
+ * @quiet: print no messages
+ *
+ * This function checks node magic number and CRC checksum. This function also
+ * validates node length to prevent UBIFS from becoming crazy when an attacker
+ * feeds it a file-system image with incorrect nodes. For example, too large
+ * node length in the common header could cause UBIFS to read memory outside of
+ * allocated buffer when checking the CRC checksum.
+ *
+ * This function returns zero in case of success %-EUCLEAN in case of bad CRC
+ * or magic.
+ */
+int ubifs_check_node(const struct ubifs_info *c, const void *buf, int lnum,
+		     int offs, int quiet)
+{
+	int err = -EINVAL, type, node_len;
+	uint32_t crc, node_crc, magic;
+	const struct ubifs_ch *ch = buf;
+
+	ubifs_assert(lnum >= 0 && lnum < c->leb_cnt && offs >= 0);
+	ubifs_assert(!(offs & 7) && offs < c->leb_size);
+
+	magic = le32_to_cpu(ch->magic);
+	if (magic != UBIFS_NODE_MAGIC) {
+		if (!quiet)
+			ubifs_err("bad magic %#08x, expected %#08x",
+				  magic, UBIFS_NODE_MAGIC);
+		err = -EUCLEAN;
+		goto out;
+	}
+
+	type = ch->node_type;
+	if (type < 0 || type >= UBIFS_NODE_TYPES_CNT) {
+		if (!quiet)
+			ubifs_err("bad node type %d", type);
+		goto out;
+	}
+
+	node_len = le32_to_cpu(ch->len);
+	if (node_len + offs > c->leb_size)
+		goto out_len;
+
+	if (c->ranges[type].max_len == 0) {
+		if (node_len != c->ranges[type].len)
+			goto out_len;
+	} else if (node_len < c->ranges[type].min_len ||
+		   node_len > c->ranges[type].max_len)
+		goto out_len;
+
+	crc = crc32(UBIFS_CRC32_INIT, buf + 8, node_len - 8);
+	node_crc = le32_to_cpu(ch->crc);
+	if (crc != node_crc) {
+		if (!quiet)
+			ubifs_err("bad CRC: calculated %#08x, read %#08x",
+				  crc, node_crc);
+		err = -EUCLEAN;
+		goto out;
+	}
+
+	return 0;
+
+out_len:
+	if (!quiet)
+		ubifs_err("bad node length %d", node_len);
+out:
+	if (!quiet) {
+		ubifs_err("bad node at LEB %d:%d", lnum, offs);
+		dbg_dump_node(c, buf);
+		dbg_dump_stack();
+	}
+	return err;
+}
+
+/**
+ * ubifs_pad - pad flash space.
+ * @c: UBIFS file-system description object
+ * @buf: buffer to put padding to
+ * @pad: how many bytes to pad
+ *
+ * The flash media obliges us to write only in chunks of %c->min_io_size and
+ * when we have to write less data we add padding node to the write-buffer and
+ * pad it to the next minimal I/O unit's boundary. Padding nodes help when the
+ * media is being scanned. If the amount of wasted space is not enough to fit a
+ * padding node which takes %UBIFS_PAD_NODE_SZ bytes, we write padding bytes
+ * pattern (%UBIFS_PADDING_BYTE).
+ *
+ * Padding nodes are also used to fill gaps when the "commit-in-gaps" method is
+ * used.
+ */
+void ubifs_pad(const struct ubifs_info *c, void *buf, int pad)
+{
+	uint32_t crc;
+
+	ubifs_assert(pad >= 0 && !(pad & 7));
+
+	if (pad >= UBIFS_PAD_NODE_SZ) {
+		struct ubifs_ch *ch = buf;
+		struct ubifs_pad_node *pad_node = buf;
+
+		ch->magic = cpu_to_le32(UBIFS_NODE_MAGIC);
+		ch->node_type = UBIFS_PAD_NODE;
+		ch->group_type = UBIFS_NO_NODE_GROUP;
+		ch->padding[0] = ch->padding[1] = 0;
+		ch->sqnum = 0;
+		ch->len = cpu_to_le32(UBIFS_PAD_NODE_SZ);
+		pad -= UBIFS_PAD_NODE_SZ;
+		pad_node->pad_len = cpu_to_le32(pad);
+		crc = crc32(UBIFS_CRC32_INIT, buf + 8, UBIFS_PAD_NODE_SZ - 8);
+		ch->crc = cpu_to_le32(crc);
+		memset(buf + UBIFS_PAD_NODE_SZ, 0, pad);
+	} else if (pad > 0)
+		/* Too little space, padding node won't fit */
+		memset(buf, UBIFS_PADDING_BYTE, pad);
+}
+
+/**
+ * next_sqnum - get next sequence number.
+ * @c: UBIFS file-system description object
+ */
+static unsigned long long next_sqnum(struct ubifs_info *c)
+{
+	unsigned long long sqnum;
+
+	spin_lock(&c->cnt_lock);
+	sqnum = ++c->max_sqnum;
+	spin_unlock(&c->cnt_lock);
+
+	if (unlikely(sqnum >= SQNUM_WARN_WATERMARK)) {
+		if (sqnum >= SQNUM_WATERMARK) {
+			ubifs_err("sequence number overflow %llu, end of life",
+				  sqnum);
+			ubifs_ro_mode(c, -EINVAL);
+		}
+		ubifs_warn("running out of sequence numbers, end of life soon");
+	}
+
+	return sqnum;
+}
+
+/**
+ * ubifs_prepare_node - prepare node to be written to flash.
+ * @c: UBIFS file-system description object
+ * @node: the node to pad
+ * @len: node length
+ * @pad: if the buffer has to be padded
+ *
+ * This function prepares node at @node to be written to the media - it
+ * calculates node CRC, fills the common header, and adds proper padding up to
+ * the next minimum I/O unit if @pad is not zero.
+ */
+void ubifs_prepare_node(struct ubifs_info *c, void *node, int len, int pad)
+{
+	uint32_t crc;
+	struct ubifs_ch *ch = node;
+	unsigned long long sqnum = next_sqnum(c);
+
+	ubifs_assert(len >= UBIFS_CH_SZ);
+
+	ch->magic = cpu_to_le32(UBIFS_NODE_MAGIC);
+	ch->len = cpu_to_le32(len);
+	ch->group_type = UBIFS_NO_NODE_GROUP;
+	ch->sqnum = cpu_to_le64(sqnum);
+	ch->padding[0] = ch->padding[1] = 0;
+	crc = crc32(UBIFS_CRC32_INIT, node + 8, len - 8);
+	ch->crc = cpu_to_le32(crc);
+
+	if (pad) {
+		len = ALIGN(len, 8);
+		pad = ALIGN(len, c->min_io_size) - len;
+		ubifs_pad(c, node + len, pad);
+	}
+}
+
+/**
+ * ubifs_prep_grp_node - prepare node of a group to be written to flash.
+ * @c: UBIFS file-system description object
+ * @node: the node to pad
+ * @len: node length
+ * @last: indicates the last node of the group
+ *
+ * This function prepares node at @node to be written to the media - it
+ * calculates node CRC and fills the common header.
+ */
+void ubifs_prep_grp_node(struct ubifs_info *c, void *node, int len, int last)
+{
+	uint32_t crc;
+	struct ubifs_ch *ch = node;
+	unsigned long long sqnum = next_sqnum(c);
+
+	ubifs_assert(len >= UBIFS_CH_SZ);
+
+	ch->magic = cpu_to_le32(UBIFS_NODE_MAGIC);
+	ch->len = cpu_to_le32(len);
+	if (last)
+		ch->group_type = UBIFS_LAST_OF_NODE_GROUP;
+	else
+		ch->group_type = UBIFS_IN_NODE_GROUP;
+	ch->sqnum = cpu_to_le64(sqnum);
+	ch->padding[0] = ch->padding[1] = 0;
+	crc = crc32(UBIFS_CRC32_INIT, node + 8, len - 8);
+	ch->crc = cpu_to_le32(crc);
+}
+
+/**
+ * wbuf_timer_callback - write-buffer timer callback function.
+ * @data: timer data (write-buffer descriptor)
+ *
+ * This function is called when the write-buffer timer expires.
+ */
+static void wbuf_timer_callback_nolock(unsigned long data)
+{
+	struct ubifs_wbuf *wbuf = (struct ubifs_wbuf *)data;
+
+	wbuf->need_sync = 1;
+	wbuf->c->need_wbuf_sync = 1;
+	ubifs_wake_up_bgt(wbuf->c);
+}
+
+/**
+ * new_wbuf_timer - start new write-buffer timer.
+ * @wbuf: write-buffer descriptor
+ */
+static void new_wbuf_timer_nolock(struct ubifs_wbuf *wbuf)
+{
+	ubifs_assert(!timer_pending(&wbuf->timer));
+
+	if (!wbuf->timeout)
+		return;
+
+	wbuf->timer.expires = jiffies + wbuf->timeout;
+	add_timer(&wbuf->timer);
+}
+
+/**
+ * cancel_wbuf_timer - cancel write-buffer timer.
+ * @wbuf: write-buffer descriptor
+ */
+static void cancel_wbuf_timer_nolock(struct ubifs_wbuf *wbuf)
+{
+	/*
+	 * If the syncer is waiting for the lock (from the background thread's
+	 * context) and another task is changing write-buffer then the syncing
+	 * should be canceled.
+	 */
+	wbuf->need_sync = 0;
+	del_timer(&wbuf->timer);
+}
+
+/**
+ * ubifs_wbuf_sync_nolock - synchronize write-buffer.
+ * @wbuf: write-buffer to synchronize
+ *
+ * This function synchronizes write-buffer @buf and returns zero in case of
+ * success or a negative error code in case of failure.
+ */
+int ubifs_wbuf_sync_nolock(struct ubifs_wbuf *wbuf)
+{
+	struct ubifs_info *c = wbuf->c;
+	int err, dirt;
+
+	cancel_wbuf_timer_nolock(wbuf);
+	if (!wbuf->used || wbuf->lnum == -1)
+		/* Write-buffer is empty or not seeked */
+		return 0;
+
+	dbg_io("LEB %d:%d, %d bytes",
+	       wbuf->lnum, wbuf->offs, wbuf->used);
+	ubifs_assert(!(c->vfs_sb->s_flags & MS_RDONLY));
+	ubifs_assert(!(wbuf->avail & 7));
+	ubifs_assert(wbuf->offs + c->min_io_size <= c->leb_size);
+
+	if (c->ro_media)
+		return -EROFS;
+
+	ubifs_pad(c, wbuf->buf + wbuf->used, wbuf->avail);
+	err = ubi_leb_write(c->ubi, wbuf->lnum, wbuf->buf, wbuf->offs,
+			    c->min_io_size, wbuf->dtype);
+	if (err) {
+		ubifs_err("cannot write %d bytes to LEB %d:%d",
+			  c->min_io_size, wbuf->lnum, wbuf->offs);
+		dbg_dump_stack();
+		return err;
+	}
+
+	dirt = wbuf->avail;
+
+	spin_lock(&wbuf->lock);
+	wbuf->offs += c->min_io_size;
+	wbuf->avail = c->min_io_size;
+	wbuf->used = 0;
+	wbuf->next_ino = 0;
+	spin_unlock(&wbuf->lock);
+
+	if (wbuf->sync_callback)
+		err = wbuf->sync_callback(c, wbuf->lnum,
+					  c->leb_size - wbuf->offs, dirt);
+	return err;
+}
+
+/**
+ * ubifs_wbuf_seek_nolock - seek write-buffer.
+ * @wbuf: write-buffer
+ * @lnum: logical eraseblock number to seek to
+ * @offs: logical eraseblock offset to seek to
+ * @dtype: data type
+ *
+ * This function targets the write buffer to logical eraseblock @lnum:@offs.
+ * The write-buffer is synchronized if it is not empty. Returns zero in case of
+ * success and a negative error code in case of failure.
+ */
+int ubifs_wbuf_seek_nolock(struct ubifs_wbuf *wbuf, int lnum, int offs,
+			   int dtype)
+{
+	const struct ubifs_info *c = wbuf->c;
+
+	dbg_io("LEB %d:%d", lnum, offs);
+	ubifs_assert(lnum >= 0 && lnum < c->leb_cnt);
+	ubifs_assert(offs >= 0 && offs <= c->leb_size);
+	ubifs_assert(offs % c->min_io_size == 0 && !(offs & 7));
+	ubifs_assert(lnum != wbuf->lnum);
+
+	if (wbuf->used > 0) {
+		int err = ubifs_wbuf_sync_nolock(wbuf);
+
+		if (err)
+			return err;
+	}
+
+	spin_lock(&wbuf->lock);
+	wbuf->lnum = lnum;
+	wbuf->offs = offs;
+	wbuf->avail = c->min_io_size;
+	wbuf->used = 0;
+	spin_unlock(&wbuf->lock);
+	wbuf->dtype = dtype;
+
+	return 0;
+}
+
+/**
+ * ubifs_bg_wbufs_sync - synchronize write-buffers.
+ * @c: UBIFS file-system description object
+ *
+ * This function is called by background thread to synchronize write-buffers.
+ * Returns zero in case of success and a negative error code in case of
+ * failure.
+ */
+int ubifs_bg_wbufs_sync(struct ubifs_info *c)
+{
+	int err, i;
+
+	if (!c->need_wbuf_sync)
+		return 0;
+	c->need_wbuf_sync = 0;
+
+	if (c->ro_media) {
+		err = -EROFS;
+		goto out_timers;
+	}
+
+	dbg_io("synchronize");
+	for (i = 0; i < c->jhead_cnt; i++) {
+		struct ubifs_wbuf *wbuf = &c->jheads[i].wbuf;
+
+		cond_resched();
+
+		/*
+		 * If the mutex is locked then wbuf is being changed, so
+		 * synchronization is not necessary.
+		 */
+		if (mutex_is_locked(&wbuf->io_mutex))
+			continue;
+
+		mutex_lock_nested(&wbuf->io_mutex, wbuf->jhead);
+		if (!wbuf->need_sync) {
+			mutex_unlock(&wbuf->io_mutex);
+			continue;
+		}
+
+		err = ubifs_wbuf_sync_nolock(wbuf);
+		mutex_unlock(&wbuf->io_mutex);
+		if (err) {
+			ubifs_err("cannot sync write-buffer, error %d", err);
+			ubifs_ro_mode(c, err);
+			goto out_timers;
+		}
+	}
+
+	return 0;
+
+out_timers:
+	/* Cancel all timers to prevent repeated errors */
+	for (i = 0; i < c->jhead_cnt; i++) {
+		struct ubifs_wbuf *wbuf = &c->jheads[i].wbuf;
+
+		mutex_lock_nested(&wbuf->io_mutex, wbuf->jhead);
+		cancel_wbuf_timer_nolock(wbuf);
+		mutex_unlock(&wbuf->io_mutex);
+	}
+	return err;
+}
+
+/**
+ * ubifs_wbuf_write_nolock - write data to flash via write-buffer.
+ * @wbuf: write-buffer
+ * @buf: node to write
+ * @len: node length
+ *
+ * This function writes data to flash via write-buffer @wbuf. This means that
+ * the last piece of the node won't reach the flash media immediately if it
+ * does not take whole minimal I/O unit. Instead, the node will sit in RAM
+ * until the write-buffer is synchronized (e.g., by timer).
+ *
+ * This function returns zero in case of success and a negative error code in
+ * case of failure. If the node cannot be written because there is no more
+ * space in this logical eraseblock, %-ENOSPC is returned.
+ */
+int ubifs_wbuf_write_nolock(struct ubifs_wbuf *wbuf, void *buf, int len)
+{
+	struct ubifs_info *c = wbuf->c;
+	int err, written, n, aligned_len = ALIGN(len, 8), offs;
+
+	dbg_io("%d bytes (%s) to wbuf at LEB %d:%d", len,
+	       dbg_ntype(((struct ubifs_ch *)buf)->node_type), wbuf->lnum,
+	       wbuf->offs + wbuf->used);
+	ubifs_assert(len > 0 && wbuf->lnum >= 0 && wbuf->lnum < c->leb_cnt);
+	ubifs_assert(wbuf->offs >= 0 && wbuf->offs % c->min_io_size == 0);
+	ubifs_assert(!(wbuf->offs & 7) && wbuf->offs <= c->leb_size);
+	ubifs_assert(wbuf->avail > 0 && wbuf->avail <= c->min_io_size);
+	ubifs_assert(mutex_is_locked(&wbuf->io_mutex));
+
+	if (c->leb_size - wbuf->offs - wbuf->used < aligned_len) {
+		err = -ENOSPC;
+		goto out;
+	}
+
+	cancel_wbuf_timer_nolock(wbuf);
+
+	if (c->ro_media)
+		return -EROFS;
+
+	if (aligned_len <= wbuf->avail) {
+		/*
+		 * The node is not very large and fits entirely within
+		 * write-buffer.
+		 */
+		memcpy(wbuf->buf + wbuf->used, buf, len);
+
+		if (aligned_len == wbuf->avail) {
+			dbg_io("flush wbuf to LEB %d:%d", wbuf->lnum,
+				wbuf->offs);
+			err = ubi_leb_write(c->ubi, wbuf->lnum, wbuf->buf,
+					    wbuf->offs, c->min_io_size,
+					    wbuf->dtype);
+			if (err)
+				goto out;
+
+			spin_lock(&wbuf->lock);
+			wbuf->offs += c->min_io_size;
+			wbuf->avail = c->min_io_size;
+			wbuf->used = 0;
+			wbuf->next_ino = 0;
+			spin_unlock(&wbuf->lock);
+		} else {
+			spin_lock(&wbuf->lock);
+			wbuf->avail -= aligned_len;
+			wbuf->used += aligned_len;
+			spin_unlock(&wbuf->lock);
+		}
+
+		goto exit;
+	}
+
+	/*
+	 * The node is large enough and does not fit entirely within current
+	 * minimal I/O unit. We have to fill and flush write-buffer and switch
+	 * to the next min. I/O unit.
+	 */
+	dbg_io("flush wbuf to LEB %d:%d", wbuf->lnum, wbuf->offs);
+	memcpy(wbuf->buf + wbuf->used, buf, wbuf->avail);
+	err = ubi_leb_write(c->ubi, wbuf->lnum, wbuf->buf, wbuf->offs,
+			    c->min_io_size, wbuf->dtype);
+	if (err)
+		goto out;
+
+	offs = wbuf->offs + c->min_io_size;
+	len -= wbuf->avail;
+	aligned_len -= wbuf->avail;
+	written = wbuf->avail;
+
+	/*
+	 * The remaining data may take more whole min. I/O units, so write the
+	 * remains multiple to min. I/O unit size directly to the flash media.
+	 * We align node length to 8-byte boundary because we anyway flash wbuf
+	 * if the remaining space is less than 8 bytes.
+	 */
+	n = aligned_len >> c->min_io_shift;
+	if (n) {
+		n <<= c->min_io_shift;
+		dbg_io("write %d bytes to LEB %d:%d", n, wbuf->lnum, offs);
+		err = ubi_leb_write(c->ubi, wbuf->lnum, buf + written, offs, n,
+				    wbuf->dtype);
+		if (err)
+			goto out;
+		offs += n;
+		aligned_len -= n;
+		len -= n;
+		written += n;
+	}
+
+	spin_lock(&wbuf->lock);
+	if (aligned_len)
+		/*
+		 * And now we have what's left and what does not take whole
+		 * min. I/O unit, so write it to the write-buffer and we are
+		 * done.
+		 */
+		memcpy(wbuf->buf, buf + written, len);
+
+	wbuf->offs = offs;
+	wbuf->used = aligned_len;
+	wbuf->avail = c->min_io_size - aligned_len;
+	wbuf->next_ino = 0;
+	spin_unlock(&wbuf->lock);
+
+exit:
+	if (wbuf->sync_callback) {
+		int free = c->leb_size - wbuf->offs - wbuf->used;
+
+		err = wbuf->sync_callback(c, wbuf->lnum, free, 0);
+		if (err)
+			goto out;
+	}
+
+	if (wbuf->used)
+		new_wbuf_timer_nolock(wbuf);
+
+	return 0;
+
+out:
+	ubifs_err("cannot write %d bytes to LEB %d:%d, error %d",
+		  len, wbuf->lnum, wbuf->offs, err);
+	dbg_dump_node(c, buf);
+	dbg_dump_stack();
+	dbg_dump_leb(c, wbuf->lnum);
+	return err;
+}
+
+/**
+ * ubifs_write_node - write node to the media.
+ * @c: UBIFS file-system description object
+ * @buf: the node to write
+ * @len: node length
+ * @lnum: logical eraseblock number
+ * @offs: offset within the logical eraseblock
+ * @dtype: node life-time hint (%UBI_LONGTERM, %UBI_SHORTTERM, %UBI_UNKNOWN)
+ *
+ * This function automatically fills node magic number, assigns sequence
+ * number, and calculates node CRC checksum. The length of the @buf buffer has
+ * to be aligned to the minimal I/O unit size. This function automatically
+ * appends padding node and padding bytes if needed. Returns zero in case of
+ * success and a negative error code in case of failure.
+ */
+int ubifs_write_node(struct ubifs_info *c, void *buf, int len, int lnum,
+		     int offs, int dtype)
+{
+	int err, buf_len = ALIGN(len, c->min_io_size);
+
+	dbg_io("LEB %d:%d, %s, length %d (aligned %d)",
+	       lnum, offs, dbg_ntype(((struct ubifs_ch *)buf)->node_type), len,
+	       buf_len);
+	ubifs_assert(lnum >= 0 && lnum < c->leb_cnt && offs >= 0);
+	ubifs_assert(offs % c->min_io_size == 0 && offs < c->leb_size);
+
+	if (c->ro_media)
+		return -EROFS;
+
+	ubifs_prepare_node(c, buf, len, 1);
+	err = ubi_leb_write(c->ubi, lnum, buf, offs, buf_len, dtype);
+	if (err) {
+		ubifs_err("cannot write %d bytes to LEB %d:%d, error %d",
+			  buf_len, lnum, offs, err);
+		dbg_dump_node(c, buf);
+		dbg_dump_stack();
+	}
+
+	return err;
+}
+
+/**
+ * ubifs_read_node_wbuf - read node from the media or write-buffer.
+ * @wbuf: wbuf to check for un-written data
+ * @buf: buffer to read to
+ * @type: node type
+ * @len: node length
+ * @lnum: logical eraseblock number
+ * @offs: offset within the logical eraseblock
+ *
+ * This function reads a node of known type and length, checks it and stores
+ * in @buf. If the node partially or fully sits in the write-buffer, this
+ * function takes data from the buffer, otherwise it reads the flash media.
+ * Returns zero in case of success, %-EUCLEAN if CRC mismatched and a negative
+ * error code in case of failure.
+ */
+int ubifs_read_node_wbuf(struct ubifs_wbuf *wbuf, void *buf, int type, int len,
+			 int lnum, int offs)
+{
+	const struct ubifs_info *c = wbuf->c;
+	int err, rlen, overlap;
+	struct ubifs_ch *ch = buf;
+
+	dbg_io("LEB %d:%d, %s, length %d", lnum, offs, dbg_ntype(type), len);
+	ubifs_assert(wbuf && lnum >= 0 && lnum < c->leb_cnt && offs >= 0);
+	ubifs_assert(!(offs & 7) && offs < c->leb_size);
+	ubifs_assert(type >= 0 && type < UBIFS_NODE_TYPES_CNT);
+
+	spin_lock(&wbuf->lock);
+	overlap = (lnum == wbuf->lnum && offs + len > wbuf->offs);
+	if (!overlap) {
+		/* We may safely unlock the write-buffer and read the data */
+		spin_unlock(&wbuf->lock);
+		return ubifs_read_node(c, buf, type, len, lnum, offs);
+	}
+
+	/* Don't read under wbuf */
+	rlen = wbuf->offs - offs;
+	if (rlen < 0)
+		rlen = 0;
+
+	/* Copy the rest from the write-buffer */
+	memcpy(buf + rlen, wbuf->buf + offs + rlen - wbuf->offs, len - rlen);
+	spin_unlock(&wbuf->lock);
+
+	if (rlen > 0) {
+		/* Read everything that goes before write-buffer */
+		err = ubi_read(c->ubi, lnum, buf, offs, rlen);
+		if (err && err != -EBADMSG) {
+			ubifs_err("failed to read node %d from LEB %d:%d, "
+				  "error %d", type, lnum, offs, err);
+			dbg_dump_stack();
+			return err;
+		}
+	}
+
+	if (type != ch->node_type) {
+		ubifs_err("bad node type (%d but expected %d)",
+			  ch->node_type, type);
+		goto out;
+	}
+
+	err = ubifs_check_node(c, buf, lnum, offs, 0);
+	if (err) {
+		ubifs_err("expected node type %d", type);
+		return err;
+	}
+
+	rlen = le32_to_cpu(ch->len);
+	if (rlen != len) {
+		ubifs_err("bad node length %d, expected %d", rlen, len);
+		goto out;
+	}
+
+	return 0;
+
+out:
+	ubifs_err("bad node at LEB %d:%d", lnum, offs);
+	dbg_dump_node(c, buf);
+	dbg_dump_stack();
+	return -EINVAL;
+}
+
+/**
+ * ubifs_read_node - read node.
+ * @c: UBIFS file-system description object
+ * @buf: buffer to read to
+ * @type: node type
+ * @len: node length (not aligned)
+ * @lnum: logical eraseblock number
+ * @offs: offset within the logical eraseblock
+ *
+ * This function reads a node of known type and and length, checks it and
+ * stores in @buf. Returns zero in case of success, %-EUCLEAN if CRC mismatched
+ * and a negative error code in case of failure.
+ */
+int ubifs_read_node(const struct ubifs_info *c, void *buf, int type, int len,
+		    int lnum, int offs)
+{
+	int err, l;
+	struct ubifs_ch *ch = buf;
+
+	dbg_io("LEB %d:%d, %s, length %d", lnum, offs, dbg_ntype(type), len);
+	ubifs_assert(lnum >= 0 && lnum < c->leb_cnt && offs >= 0);
+	ubifs_assert(len >= UBIFS_CH_SZ && offs + len <= c->leb_size);
+	ubifs_assert(!(offs & 7) && offs < c->leb_size);
+	ubifs_assert(type >= 0 && type < UBIFS_NODE_TYPES_CNT);
+
+	err = ubi_read(c->ubi, lnum, buf, offs, len);
+	if (err && err != -EBADMSG) {
+		ubifs_err("cannot read node %d from LEB %d:%d, error %d",
+			  type, lnum, offs, err);
+		return err;
+	}
+
+	if (type != ch->node_type) {
+		ubifs_err("bad node type (%d but expected %d)",
+			  ch->node_type, type);
+		goto out;
+	}
+
+	err = ubifs_check_node(c, buf, lnum, offs, 0);
+	if (err) {
+		ubifs_err("expected node type %d", type);
+		return err;
+	}
+
+	l = le32_to_cpu(ch->len);
+	if (l != len) {
+		ubifs_err("bad node length %d, expected %d", l, len);
+		goto out;
+	}
+
+	return 0;
+
+out:
+	ubifs_err("bad node at LEB %d:%d", lnum, offs);
+	dbg_dump_node(c, buf);
+	dbg_dump_stack();
+	return -EINVAL;
+}
+
+/**
+ * ubifs_wbuf_init - initialize write-buffer.
+ * @c: UBIFS file-system description object
+ * @wbuf: write-buffer to initialize
+ *
+ * This function initializes write buffer. Returns zero in case of success
+ * %-ENOMEM in case of failure.
+ */
+int ubifs_wbuf_init(struct ubifs_info *c, struct ubifs_wbuf *wbuf)
+{
+	size_t size;
+
+	wbuf->buf = kmalloc(c->min_io_size, GFP_KERNEL);
+	if (!wbuf->buf)
+		return -ENOMEM;
+
+	size = (c->min_io_size / UBIFS_CH_SZ + 1) * sizeof(ino_t);
+	wbuf->inodes = kmalloc(size, GFP_KERNEL);
+	if (!wbuf->inodes) {
+		kfree(wbuf->buf);
+		wbuf->buf = NULL;
+		return -ENOMEM;
+	}
+
+	wbuf->used = 0;
+	wbuf->lnum = wbuf->offs = -1;
+	wbuf->avail = c->min_io_size;
+	wbuf->dtype = UBI_UNKNOWN;
+	wbuf->sync_callback = NULL;
+	mutex_init(&wbuf->io_mutex);
+	spin_lock_init(&wbuf->lock);
+
+	wbuf->c = c;
+	init_timer(&wbuf->timer);
+	wbuf->timer.function = wbuf_timer_callback_nolock;
+	wbuf->timer.data = (unsigned long)wbuf;
+	wbuf->timeout = DEFAULT_WBUF_TIMEOUT;
+	wbuf->next_ino = 0;
+
+	return 0;
+}
+
+/**
+ * ubifs_wbuf_add_ino_nolock - add an inode number into the wbuf inode array.
+ * @wbuf: the write-buffer whereto add
+ * @inum: the inode number
+ *
+ * This function adds an inode number to the inode array of the write-buffer.
+ */
+void ubifs_wbuf_add_ino_nolock(struct ubifs_wbuf *wbuf, ino_t inum)
+{
+	if (!wbuf->buf)
+		/* NOR flash or something similar */
+		return;
+
+	spin_lock(&wbuf->lock);
+	if (wbuf->used)
+		wbuf->inodes[wbuf->next_ino++] = inum;
+	spin_unlock(&wbuf->lock);
+}
+
+/**
+ * wbuf_has_ino - returns if the wbuf contains data from the inode.
+ * @wbuf: the write-buffer
+ * @inum: the inode number
+ *
+ * This function returns with %1 if the write-buffer contains some data from the
+ * given inode otherwise it returns with %0.
+ */
+static int wbuf_has_ino(struct ubifs_wbuf *wbuf, ino_t inum)
+{
+	int i, ret = 0;
+
+	spin_lock(&wbuf->lock);
+	for (i = 0; i < wbuf->next_ino; i++)
+		if (inum == wbuf->inodes[i]) {
+			ret = 1;
+			break;
+		}
+	spin_unlock(&wbuf->lock);
+
+	return ret;
+}
+
+/**
+ * ubifs_sync_wbufs_by_inode - synchronize write-buffers for an inode.
+ * @c: UBIFS file-system description object
+ * @inode: inode to synchronize
+ *
+ * This function synchronizes write-buffers which contain nodes belonging to
+ * @inode. Returns zero in case of success and a negative error code in case of
+ * failure.
+ */
+int ubifs_sync_wbufs_by_inode(struct ubifs_info *c, struct inode *inode)
+{
+	int i, err = 0;
+
+	for (i = 0; i < c->jhead_cnt; i++) {
+		struct ubifs_wbuf *wbuf = &c->jheads[i].wbuf;
+
+		if (i == GCHD)
+			/*
+			 * GC head is special, do not look at it. Even if the
+			 * head contains something related to this inode, it is
+			 * a _copy_ of corresponding on-flash node which sits
+			 * somewhere else.
+			 */
+			continue;
+
+		if (!wbuf_has_ino(wbuf, inode->i_ino))
+			continue;
+
+		mutex_lock_nested(&wbuf->io_mutex, wbuf->jhead);
+		if (wbuf_has_ino(wbuf, inode->i_ino))
+			err = ubifs_wbuf_sync_nolock(wbuf);
+		mutex_unlock(&wbuf->io_mutex);
+
+		if (err) {
+			ubifs_ro_mode(c, err);
+			return err;
+		}
+	}
+	return 0;
+}
diff --git a/fs/ubifs/ioctl.c b/fs/ubifs/ioctl.c
new file mode 100644
index 00000000000..5e82cffe969
--- /dev/null
+++ b/fs/ubifs/ioctl.c
@@ -0,0 +1,204 @@
+/*
+ * This file is part of UBIFS.
+ *
+ * Copyright (C) 2006-2008 Nokia Corporation.
+ * Copyright (C) 2006, 2007 University of Szeged, Hungary
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 as published by
+ * the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
+ * more details.
+ *
+ * You should have received a copy of the GNU General Public License along with
+ * this program; if not, write to the Free Software Foundation, Inc., 51
+ * Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
+ *
+ * Authors: Zoltan Sogor
+ *          Artem Bityutskiy (Битюцкий Артём)
+ *          Adrian Hunter
+ */
+
+/* This file implements EXT2-compatible extended attribute ioctl() calls */
+
+#include <linux/compat.h>
+#include <linux/smp_lock.h>
+#include <linux/mount.h>
+#include "ubifs.h"
+
+/**
+ * ubifs_set_inode_flags - set VFS inode flags.
+ * @inode: VFS inode to set flags for
+ *
+ * This function propagates flags from UBIFS inode object to VFS inode object.
+ */
+void ubifs_set_inode_flags(struct inode *inode)
+{
+	unsigned int flags = ubifs_inode(inode)->flags;
+
+	inode->i_flags &= ~(S_SYNC | S_APPEND | S_IMMUTABLE | S_DIRSYNC);
+	if (flags & UBIFS_SYNC_FL)
+		inode->i_flags |= S_SYNC;
+	if (flags & UBIFS_APPEND_FL)
+		inode->i_flags |= S_APPEND;
+	if (flags & UBIFS_IMMUTABLE_FL)
+		inode->i_flags |= S_IMMUTABLE;
+	if (flags & UBIFS_DIRSYNC_FL)
+		inode->i_flags |= S_DIRSYNC;
+}
+
+/*
+ * ioctl2ubifs - convert ioctl inode flags to UBIFS inode flags.
+ * @ioctl_flags: flags to convert
+ *
+ * This function convert ioctl flags (@FS_COMPR_FL, etc) to UBIFS inode flags
+ * (@UBIFS_COMPR_FL, etc).
+ */
+static int ioctl2ubifs(int ioctl_flags)
+{
+	int ubifs_flags = 0;
+
+	if (ioctl_flags & FS_COMPR_FL)
+		ubifs_flags |= UBIFS_COMPR_FL;
+	if (ioctl_flags & FS_SYNC_FL)
+		ubifs_flags |= UBIFS_SYNC_FL;
+	if (ioctl_flags & FS_APPEND_FL)
+		ubifs_flags |= UBIFS_APPEND_FL;
+	if (ioctl_flags & FS_IMMUTABLE_FL)
+		ubifs_flags |= UBIFS_IMMUTABLE_FL;
+	if (ioctl_flags & FS_DIRSYNC_FL)
+		ubifs_flags |= UBIFS_DIRSYNC_FL;
+
+	return ubifs_flags;
+}
+
+/*
+ * ubifs2ioctl - convert UBIFS inode flags to ioctl inode flags.
+ * @ubifs_flags: flags to convert
+ *
+ * This function convert UBIFS (@UBIFS_COMPR_FL, etc) to ioctl flags
+ * (@FS_COMPR_FL, etc).
+ */
+static int ubifs2ioctl(int ubifs_flags)
+{
+	int ioctl_flags = 0;
+
+	if (ubifs_flags & UBIFS_COMPR_FL)
+		ioctl_flags |= FS_COMPR_FL;
+	if (ubifs_flags & UBIFS_SYNC_FL)
+		ioctl_flags |= FS_SYNC_FL;
+	if (ubifs_flags & UBIFS_APPEND_FL)
+		ioctl_flags |= FS_APPEND_FL;
+	if (ubifs_flags & UBIFS_IMMUTABLE_FL)
+		ioctl_flags |= FS_IMMUTABLE_FL;
+	if (ubifs_flags & UBIFS_DIRSYNC_FL)
+		ioctl_flags |= FS_DIRSYNC_FL;
+
+	return ioctl_flags;
+}
+
+static int setflags(struct inode *inode, int flags)
+{
+	int oldflags, err, release;
+	struct ubifs_inode *ui = ubifs_inode(inode);
+	struct ubifs_info *c = inode->i_sb->s_fs_info;
+	struct ubifs_budget_req req = { .dirtied_ino = 1,
+					.dirtied_ino_d = ui->data_len };
+
+	err = ubifs_budget_space(c, &req);
+	if (err)
+		return err;
+
+	/*
+	 * The IMMUTABLE and APPEND_ONLY flags can only be changed by
+	 * the relevant capability.
+	 */
+	mutex_lock(&ui->ui_mutex);
+	oldflags = ubifs2ioctl(ui->flags);
+	if ((flags ^ oldflags) & (FS_APPEND_FL | FS_IMMUTABLE_FL)) {
+		if (!capable(CAP_LINUX_IMMUTABLE)) {
+			err = -EPERM;
+			goto out_unlock;
+		}
+	}
+
+	ui->flags = ioctl2ubifs(flags);
+	ubifs_set_inode_flags(inode);
+	inode->i_ctime = ubifs_current_time(inode);
+	release = ui->dirty;
+	mark_inode_dirty_sync(inode);
+	mutex_unlock(&ui->ui_mutex);
+
+	if (release)
+		ubifs_release_budget(c, &req);
+	if (IS_SYNC(inode))
+		err = write_inode_now(inode, 1);
+	return err;
+
+out_unlock:
+	ubifs_err("can't modify inode %lu attributes", inode->i_ino);
+	mutex_unlock(&ui->ui_mutex);
+	ubifs_release_budget(c, &req);
+	return err;
+}
+
+long ubifs_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
+{
+	int flags, err;
+	struct inode *inode = file->f_path.dentry->d_inode;
+
+	switch (cmd) {
+	case FS_IOC_GETFLAGS:
+		flags = ubifs2ioctl(ubifs_inode(inode)->flags);
+
+		return put_user(flags, (int __user *) arg);
+
+	case FS_IOC_SETFLAGS: {
+		if (IS_RDONLY(inode))
+			return -EROFS;
+
+		if (!is_owner_or_cap(inode))
+			return -EACCES;
+
+		if (get_user(flags, (int __user *) arg))
+			return -EFAULT;
+
+		if (!S_ISDIR(inode->i_mode))
+			flags &= ~FS_DIRSYNC_FL;
+
+		/*
+		 * Make sure the file-system is read-write and make sure it
+		 * will not become read-only while we are changing the flags.
+		 */
+		err = mnt_want_write(file->f_path.mnt);
+		if (err)
+			return err;
+		err = setflags(inode, flags);
+		mnt_drop_write(file->f_path.mnt);
+		return err;
+	}
+
+	default:
+		return -ENOTTY;
+	}
+}
+
+#ifdef CONFIG_COMPAT
+long ubifs_compat_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
+{
+	switch (cmd) {
+	case FS_IOC32_GETFLAGS:
+		cmd = FS_IOC_GETFLAGS;
+		break;
+	case FS_IOC32_SETFLAGS:
+		cmd = FS_IOC_SETFLAGS;
+		break;
+	default:
+		return -ENOIOCTLCMD;
+	}
+	return ubifs_ioctl(file, cmd, (unsigned long)compat_ptr(arg));
+}
+#endif
diff --git a/fs/ubifs/journal.c b/fs/ubifs/journal.c
new file mode 100644
index 00000000000..283155abe5f
--- /dev/null
+++ b/fs/ubifs/journal.c
@@ -0,0 +1,1387 @@
+/*
+ * This file is part of UBIFS.
+ *
+ * Copyright (C) 2006-2008 Nokia Corporation.
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 as published by
+ * the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
+ * more details.
+ *
+ * You should have received a copy of the GNU General Public License along with
+ * this program; if not, write to the Free Software Foundation, Inc., 51
+ * Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
+ *
+ * Authors: Artem Bityutskiy (Битюцкий Артём)
+ *          Adrian Hunter
+ */
+
+/*
+ * This file implements UBIFS journal.
+ *
+ * The journal consists of 2 parts - the log and bud LEBs. The log has fixed
+ * length and position, while a bud logical eraseblock is any LEB in the main
+ * area. Buds contain file system data - data nodes, inode nodes, etc. The log
+ * contains only references to buds and some other stuff like commit
+ * start node. The idea is that when we commit the journal, we do
+ * not copy the data, the buds just become indexed. Since after the commit the
+ * nodes in bud eraseblocks become leaf nodes of the file system index tree, we
+ * use term "bud". Analogy is obvious, bud eraseblocks contain nodes which will
+ * become leafs in the future.
+ *
+ * The journal is multi-headed because we want to write data to the journal as
+ * optimally as possible. It is nice to have nodes belonging to the same inode
+ * in one LEB, so we may write data owned by different inodes to different
+ * journal heads, although at present only one data head is used.
+ *
+ * For recovery reasons, the base head contains all inode nodes, all directory
+ * entry nodes and all truncate nodes. This means that the other heads contain
+ * only data nodes.
+ *
+ * Bud LEBs may be half-indexed. For example, if the bud was not full at the
+ * time of commit, the bud is retained to continue to be used in the journal,
+ * even though the "front" of the LEB is now indexed. In that case, the log
+ * reference contains the offset where the bud starts for the purposes of the
+ * journal.
+ *
+ * The journal size has to be limited, because the larger is the journal, the
+ * longer it takes to mount UBIFS (scanning the journal) and the more memory it
+ * takes (indexing in the TNC).
+ *
+ * All the journal write operations like 'ubifs_jnl_update()' here, which write
+ * multiple UBIFS nodes to the journal at one go, are atomic with respect to
+ * unclean reboots. Should the unclean reboot happen, the recovery code drops
+ * all the nodes.
+ */
+
+#include "ubifs.h"
+
+/**
+ * zero_ino_node_unused - zero out unused fields of an on-flash inode node.
+ * @ino: the inode to zero out
+ */
+static inline void zero_ino_node_unused(struct ubifs_ino_node *ino)
+{
+	memset(ino->padding1, 0, 4);
+	memset(ino->padding2, 0, 26);
+}
+
+/**
+ * zero_dent_node_unused - zero out unused fields of an on-flash directory
+ *                         entry node.
+ * @dent: the directory entry to zero out
+ */
+static inline void zero_dent_node_unused(struct ubifs_dent_node *dent)
+{
+	dent->padding1 = 0;
+	memset(dent->padding2, 0, 4);
+}
+
+/**
+ * zero_data_node_unused - zero out unused fields of an on-flash data node.
+ * @data: the data node to zero out
+ */
+static inline void zero_data_node_unused(struct ubifs_data_node *data)
+{
+	memset(data->padding, 0, 2);
+}
+
+/**
+ * zero_trun_node_unused - zero out unused fields of an on-flash truncation
+ *                         node.
+ * @trun: the truncation node to zero out
+ */
+static inline void zero_trun_node_unused(struct ubifs_trun_node *trun)
+{
+	memset(trun->padding, 0, 12);
+}
+
+/**
+ * reserve_space - reserve space in the journal.
+ * @c: UBIFS file-system description object
+ * @jhead: journal head number
+ * @len: node length
+ *
+ * This function reserves space in journal head @head. If the reservation
+ * succeeded, the journal head stays locked and later has to be unlocked using
+ * 'release_head()'. 'write_node()' and 'write_head()' functions also unlock
+ * it. Returns zero in case of success, %-EAGAIN if commit has to be done, and
+ * other negative error codes in case of other failures.
+ */
+static int reserve_space(struct ubifs_info *c, int jhead, int len)
+{
+	int err = 0, err1, retries = 0, avail, lnum, offs, free, squeeze;
+	struct ubifs_wbuf *wbuf = &c->jheads[jhead].wbuf;
+
+	/*
+	 * Typically, the base head has smaller nodes written to it, so it is
+	 * better to try to allocate space at the ends of eraseblocks. This is
+	 * what the squeeze parameter does.
+	 */
+	squeeze = (jhead == BASEHD);
+again:
+	mutex_lock_nested(&wbuf->io_mutex, wbuf->jhead);
+
+	if (c->ro_media) {
+		err = -EROFS;
+		goto out_unlock;
+	}
+
+	avail = c->leb_size - wbuf->offs - wbuf->used;
+	if (wbuf->lnum != -1 && avail >= len)
+		return 0;
+
+	/*
+	 * Write buffer wasn't seek'ed or there is no enough space - look for an
+	 * LEB with some empty space.
+	 */
+	lnum = ubifs_find_free_space(c, len, &free, squeeze);
+	if (lnum >= 0) {
+		/* Found an LEB, add it to the journal head */
+		offs = c->leb_size - free;
+		err = ubifs_add_bud_to_log(c, jhead, lnum, offs);
+		if (err)
+			goto out_return;
+		/* A new bud was successfully allocated and added to the log */
+		goto out;
+	}
+
+	err = lnum;
+	if (err != -ENOSPC)
+		goto out_unlock;
+
+	/*
+	 * No free space, we have to run garbage collector to make
+	 * some. But the write-buffer mutex has to be unlocked because
+	 * GC also takes it.
+	 */
+	dbg_jnl("no free space  jhead %d, run GC", jhead);
+	mutex_unlock(&wbuf->io_mutex);
+
+	lnum = ubifs_garbage_collect(c, 0);
+	if (lnum < 0) {
+		err = lnum;
+		if (err != -ENOSPC)
+			return err;
+
+		/*
+		 * GC could not make a free LEB. But someone else may
+		 * have allocated new bud for this journal head,
+		 * because we dropped @wbuf->io_mutex, so try once
+		 * again.
+		 */
+		dbg_jnl("GC couldn't make a free LEB for jhead %d", jhead);
+		if (retries++ < 2) {
+			dbg_jnl("retry (%d)", retries);
+			goto again;
+		}
+
+		dbg_jnl("return -ENOSPC");
+		return err;
+	}
+
+	mutex_lock_nested(&wbuf->io_mutex, wbuf->jhead);
+	dbg_jnl("got LEB %d for jhead %d", lnum, jhead);
+	avail = c->leb_size - wbuf->offs - wbuf->used;
+
+	if (wbuf->lnum != -1 && avail >= len) {
+		/*
+		 * Someone else has switched the journal head and we have
+		 * enough space now. This happens when more then one process is
+		 * trying to write to the same journal head at the same time.
+		 */
+		dbg_jnl("return LEB %d back, already have LEB %d:%d",
+			lnum, wbuf->lnum, wbuf->offs + wbuf->used);
+		err = ubifs_return_leb(c, lnum);
+		if (err)
+			goto out_unlock;
+		return 0;
+	}
+
+	err = ubifs_add_bud_to_log(c, jhead, lnum, 0);
+	if (err)
+		goto out_return;
+	offs = 0;
+
+out:
+	err = ubifs_wbuf_seek_nolock(wbuf, lnum, offs, UBI_SHORTTERM);
+	if (err)
+		goto out_unlock;
+
+	return 0;
+
+out_unlock:
+	mutex_unlock(&wbuf->io_mutex);
+	return err;
+
+out_return:
+	/* An error occurred and the LEB has to be returned to lprops */
+	ubifs_assert(err < 0);
+	err1 = ubifs_return_leb(c, lnum);
+	if (err1 && err == -EAGAIN)
+		/*
+		 * Return original error code only if it is not %-EAGAIN,
+		 * which is not really an error. Otherwise, return the error
+		 * code of 'ubifs_return_leb()'.
+		 */
+		err = err1;
+	mutex_unlock(&wbuf->io_mutex);
+	return err;
+}
+
+/**
+ * write_node - write node to a journal head.
+ * @c: UBIFS file-system description object
+ * @jhead: journal head
+ * @node: node to write
+ * @len: node length
+ * @lnum: LEB number written is returned here
+ * @offs: offset written is returned here
+ *
+ * This function writes a node to reserved space of journal head @jhead.
+ * Returns zero in case of success and a negative error code in case of
+ * failure.
+ */
+static int write_node(struct ubifs_info *c, int jhead, void *node, int len,
+		      int *lnum, int *offs)
+{
+	struct ubifs_wbuf *wbuf = &c->jheads[jhead].wbuf;
+
+	ubifs_assert(jhead != GCHD);
+
+	*lnum = c->jheads[jhead].wbuf.lnum;
+	*offs = c->jheads[jhead].wbuf.offs + c->jheads[jhead].wbuf.used;
+
+	dbg_jnl("jhead %d, LEB %d:%d, len %d", jhead, *lnum, *offs, len);
+	ubifs_prepare_node(c, node, len, 0);
+
+	return ubifs_wbuf_write_nolock(wbuf, node, len);
+}
+
+/**
+ * write_head - write data to a journal head.
+ * @c: UBIFS file-system description object
+ * @jhead: journal head
+ * @buf: buffer to write
+ * @len: length to write
+ * @lnum: LEB number written is returned here
+ * @offs: offset written is returned here
+ * @sync: non-zero if the write-buffer has to by synchronized
+ *
+ * This function is the same as 'write_node()' but it does not assume the
+ * buffer it is writing is a node, so it does not prepare it (which means
+ * initializing common header and calculating CRC).
+ */
+static int write_head(struct ubifs_info *c, int jhead, void *buf, int len,
+		      int *lnum, int *offs, int sync)
+{
+	int err;
+	struct ubifs_wbuf *wbuf = &c->jheads[jhead].wbuf;
+
+	ubifs_assert(jhead != GCHD);
+
+	*lnum = c->jheads[jhead].wbuf.lnum;
+	*offs = c->jheads[jhead].wbuf.offs + c->jheads[jhead].wbuf.used;
+	dbg_jnl("jhead %d, LEB %d:%d, len %d", jhead, *lnum, *offs, len);
+
+	err = ubifs_wbuf_write_nolock(wbuf, buf, len);
+	if (err)
+		return err;
+	if (sync)
+		err = ubifs_wbuf_sync_nolock(wbuf);
+	return err;
+}
+
+/**
+ * make_reservation - reserve journal space.
+ * @c: UBIFS file-system description object
+ * @jhead: journal head
+ * @len: how many bytes to reserve
+ *
+ * This function makes space reservation in journal head @jhead. The function
+ * takes the commit lock and locks the journal head, and the caller has to
+ * unlock the head and finish the reservation with 'finish_reservation()'.
+ * Returns zero in case of success and a negative error code in case of
+ * failure.
+ *
+ * Note, the journal head may be unlocked as soon as the data is written, while
+ * the commit lock has to be released after the data has been added to the
+ * TNC.
+ */
+static int make_reservation(struct ubifs_info *c, int jhead, int len)
+{
+	int err, cmt_retries = 0, nospc_retries = 0;
+
+again:
+	down_read(&c->commit_sem);
+	err = reserve_space(c, jhead, len);
+	if (!err)
+		return 0;
+	up_read(&c->commit_sem);
+
+	if (err == -ENOSPC) {
+		/*
+		 * GC could not make any progress. We should try to commit
+		 * once because it could make some dirty space and GC would
+		 * make progress, so make the error -EAGAIN so that the below
+		 * will commit and re-try.
+		 */
+		if (nospc_retries++ < 2) {
+			dbg_jnl("no space, retry");
+			err = -EAGAIN;
+		}
+
+		/*
+		 * This means that the budgeting is incorrect. We always have
+		 * to be able to write to the media, because all operations are
+		 * budgeted. Deletions are not budgeted, though, but we reserve
+		 * an extra LEB for them.
+		 */
+	}
+
+	if (err != -EAGAIN)
+		goto out;
+
+	/*
+	 * -EAGAIN means that the journal is full or too large, or the above
+	 * code wants to do one commit. Do this and re-try.
+	 */
+	if (cmt_retries > 128) {
+		/*
+		 * This should not happen unless the journal size limitations
+		 * are too tough.
+		 */
+		ubifs_err("stuck in space allocation");
+		err = -ENOSPC;
+		goto out;
+	} else if (cmt_retries > 32)
+		ubifs_warn("too many space allocation re-tries (%d)",
+			   cmt_retries);
+
+	dbg_jnl("-EAGAIN, commit and retry (retried %d times)",
+		cmt_retries);
+	cmt_retries += 1;
+
+	err = ubifs_run_commit(c);
+	if (err)
+		return err;
+	goto again;
+
+out:
+	ubifs_err("cannot reserve %d bytes in jhead %d, error %d",
+		  len, jhead, err);
+	if (err == -ENOSPC) {
+		/* This are some budgeting problems, print useful information */
+		down_write(&c->commit_sem);
+		spin_lock(&c->space_lock);
+		dbg_dump_stack();
+		dbg_dump_budg(c);
+		spin_unlock(&c->space_lock);
+		dbg_dump_lprops(c);
+		cmt_retries = dbg_check_lprops(c);
+		up_write(&c->commit_sem);
+	}
+	return err;
+}
+
+/**
+ * release_head - release a journal head.
+ * @c: UBIFS file-system description object
+ * @jhead: journal head
+ *
+ * This function releases journal head @jhead which was locked by
+ * the 'make_reservation()' function. It has to be called after each successful
+ * 'make_reservation()' invocation.
+ */
+static inline void release_head(struct ubifs_info *c, int jhead)
+{
+	mutex_unlock(&c->jheads[jhead].wbuf.io_mutex);
+}
+
+/**
+ * finish_reservation - finish a reservation.
+ * @c: UBIFS file-system description object
+ *
+ * This function finishes journal space reservation. It must be called after
+ * 'make_reservation()'.
+ */
+static void finish_reservation(struct ubifs_info *c)
+{
+	up_read(&c->commit_sem);
+}
+
+/**
+ * get_dent_type - translate VFS inode mode to UBIFS directory entry type.
+ * @mode: inode mode
+ */
+static int get_dent_type(int mode)
+{
+	switch (mode & S_IFMT) {
+	case S_IFREG:
+		return UBIFS_ITYPE_REG;
+	case S_IFDIR:
+		return UBIFS_ITYPE_DIR;
+	case S_IFLNK:
+		return UBIFS_ITYPE_LNK;
+	case S_IFBLK:
+		return UBIFS_ITYPE_BLK;
+	case S_IFCHR:
+		return UBIFS_ITYPE_CHR;
+	case S_IFIFO:
+		return UBIFS_ITYPE_FIFO;
+	case S_IFSOCK:
+		return UBIFS_ITYPE_SOCK;
+	default:
+		BUG();
+	}
+	return 0;
+}
+
+/**
+ * pack_inode - pack an inode node.
+ * @c: UBIFS file-system description object
+ * @ino: buffer in which to pack inode node
+ * @inode: inode to pack
+ * @last: indicates the last node of the group
+ * @last_reference: non-zero if this is a deletion inode
+ */
+static void pack_inode(struct ubifs_info *c, struct ubifs_ino_node *ino,
+		       const struct inode *inode, int last,
+		       int last_reference)
+{
+	int data_len = 0;
+	struct ubifs_inode *ui = ubifs_inode(inode);
+
+	ino->ch.node_type = UBIFS_INO_NODE;
+	ino_key_init_flash(c, &ino->key, inode->i_ino);
+	ino->creat_sqnum = cpu_to_le64(ui->creat_sqnum);
+	ino->atime_sec  = cpu_to_le64(inode->i_atime.tv_sec);
+	ino->atime_nsec = cpu_to_le32(inode->i_atime.tv_nsec);
+	ino->ctime_sec  = cpu_to_le64(inode->i_ctime.tv_sec);
+	ino->ctime_nsec = cpu_to_le32(inode->i_ctime.tv_nsec);
+	ino->mtime_sec  = cpu_to_le64(inode->i_mtime.tv_sec);
+	ino->mtime_nsec = cpu_to_le32(inode->i_mtime.tv_nsec);
+	ino->uid   = cpu_to_le32(inode->i_uid);
+	ino->gid   = cpu_to_le32(inode->i_gid);
+	ino->mode  = cpu_to_le32(inode->i_mode);
+	ino->flags = cpu_to_le32(ui->flags);
+	ino->size  = cpu_to_le64(ui->ui_size);
+	ino->nlink = cpu_to_le32(inode->i_nlink);
+	ino->compr_type  = cpu_to_le16(ui->compr_type);
+	ino->data_len    = cpu_to_le32(ui->data_len);
+	ino->xattr_cnt   = cpu_to_le32(ui->xattr_cnt);
+	ino->xattr_size  = cpu_to_le32(ui->xattr_size);
+	ino->xattr_names = cpu_to_le32(ui->xattr_names);
+	zero_ino_node_unused(ino);
+
+	/*
+	 * Drop the attached data if this is a deletion inode, the data is not
+	 * needed anymore.
+	 */
+	if (!last_reference) {
+		memcpy(ino->data, ui->data, ui->data_len);
+		data_len = ui->data_len;
+	}
+
+	ubifs_prep_grp_node(c, ino, UBIFS_INO_NODE_SZ + data_len, last);
+}
+
+/**
+ * mark_inode_clean - mark UBIFS inode as clean.
+ * @c: UBIFS file-system description object
+ * @ui: UBIFS inode to mark as clean
+ *
+ * This helper function marks UBIFS inode @ui as clean by cleaning the
+ * @ui->dirty flag and releasing its budget. Note, VFS may still treat the
+ * inode as dirty and try to write it back, but 'ubifs_write_inode()' would
+ * just do nothing.
+ */
+static void mark_inode_clean(struct ubifs_info *c, struct ubifs_inode *ui)
+{
+	if (ui->dirty)
+		ubifs_release_dirty_inode_budget(c, ui);
+	ui->dirty = 0;
+}
+
+/**
+ * ubifs_jnl_update - update inode.
+ * @c: UBIFS file-system description object
+ * @dir: parent inode or host inode in case of extended attributes
+ * @nm: directory entry name
+ * @inode: inode to update
+ * @deletion: indicates a directory entry deletion i.e unlink or rmdir
+ * @xent: non-zero if the directory entry is an extended attribute entry
+ *
+ * This function updates an inode by writing a directory entry (or extended
+ * attribute entry), the inode itself, and the parent directory inode (or the
+ * host inode) to the journal.
+ *
+ * The function writes the host inode @dir last, which is important in case of
+ * extended attributes. Indeed, then we guarantee that if the host inode gets
+ * synchronized (with 'fsync()'), and the write-buffer it sits in gets flushed,
+ * the extended attribute inode gets flushed too. And this is exactly what the
+ * user expects - synchronizing the host inode synchronizes its extended
+ * attributes. Similarly, this guarantees that if @dir is synchronized, its
+ * directory entry corresponding to @nm gets synchronized too.
+ *
+ * If the inode (@inode) or the parent directory (@dir) are synchronous, this
+ * function synchronizes the write-buffer.
+ *
+ * This function marks the @dir and @inode inodes as clean and returns zero on
+ * success. In case of failure, a negative error code is returned.
+ */
+int ubifs_jnl_update(struct ubifs_info *c, const struct inode *dir,
+		     const struct qstr *nm, const struct inode *inode,
+		     int deletion, int xent)
+{
+	int err, dlen, ilen, len, lnum, ino_offs, dent_offs;
+	int aligned_dlen, aligned_ilen, sync = IS_DIRSYNC(dir);
+	int last_reference = !!(deletion && inode->i_nlink == 0);
+	struct ubifs_inode *ui = ubifs_inode(inode);
+	struct ubifs_inode *dir_ui = ubifs_inode(dir);
+	struct ubifs_dent_node *dent;
+	struct ubifs_ino_node *ino;
+	union ubifs_key dent_key, ino_key;
+
+	dbg_jnl("ino %lu, dent '%.*s', data len %d in dir ino %lu",
+		inode->i_ino, nm->len, nm->name, ui->data_len, dir->i_ino);
+	ubifs_assert(dir_ui->data_len == 0);
+	ubifs_assert(mutex_is_locked(&dir_ui->ui_mutex));
+
+	dlen = UBIFS_DENT_NODE_SZ + nm->len + 1;
+	ilen = UBIFS_INO_NODE_SZ;
+
+	/*
+	 * If the last reference to the inode is being deleted, then there is
+	 * no need to attach and write inode data, it is being deleted anyway.
+	 * And if the inode is being deleted, no need to synchronize
+	 * write-buffer even if the inode is synchronous.
+	 */
+	if (!last_reference) {
+		ilen += ui->data_len;
+		sync |= IS_SYNC(inode);
+	}
+
+	aligned_dlen = ALIGN(dlen, 8);
+	aligned_ilen = ALIGN(ilen, 8);
+	len = aligned_dlen + aligned_ilen + UBIFS_INO_NODE_SZ;
+	dent = kmalloc(len, GFP_NOFS);
+	if (!dent)
+		return -ENOMEM;
+
+	/* Make reservation before allocating sequence numbers */
+	err = make_reservation(c, BASEHD, len);
+	if (err)
+		goto out_free;
+
+	if (!xent) {
+		dent->ch.node_type = UBIFS_DENT_NODE;
+		dent_key_init(c, &dent_key, dir->i_ino, nm);
+	} else {
+		dent->ch.node_type = UBIFS_XENT_NODE;
+		xent_key_init(c, &dent_key, dir->i_ino, nm);
+	}
+
+	key_write(c, &dent_key, dent->key);
+	dent->inum = deletion ? 0 : cpu_to_le64(inode->i_ino);
+	dent->type = get_dent_type(inode->i_mode);
+	dent->nlen = cpu_to_le16(nm->len);
+	memcpy(dent->name, nm->name, nm->len);
+	dent->name[nm->len] = '\0';
+	zero_dent_node_unused(dent);
+	ubifs_prep_grp_node(c, dent, dlen, 0);
+
+	ino = (void *)dent + aligned_dlen;
+	pack_inode(c, ino, inode, 0, last_reference);
+	ino = (void *)ino + aligned_ilen;
+	pack_inode(c, ino, dir, 1, 0);
+
+	if (last_reference) {
+		err = ubifs_add_orphan(c, inode->i_ino);
+		if (err) {
+			release_head(c, BASEHD);
+			goto out_finish;
+		}
+	}
+
+	err = write_head(c, BASEHD, dent, len, &lnum, &dent_offs, sync);
+	if (err)
+		goto out_release;
+	if (!sync) {
+		struct ubifs_wbuf *wbuf = &c->jheads[BASEHD].wbuf;
+
+		ubifs_wbuf_add_ino_nolock(wbuf, inode->i_ino);
+		ubifs_wbuf_add_ino_nolock(wbuf, dir->i_ino);
+	}
+	release_head(c, BASEHD);
+	kfree(dent);
+
+	if (deletion) {
+		err = ubifs_tnc_remove_nm(c, &dent_key, nm);
+		if (err)
+			goto out_ro;
+		err = ubifs_add_dirt(c, lnum, dlen);
+	} else
+		err = ubifs_tnc_add_nm(c, &dent_key, lnum, dent_offs, dlen, nm);
+	if (err)
+		goto out_ro;
+
+	/*
+	 * Note, we do not remove the inode from TNC even if the last reference
+	 * to it has just been deleted, because the inode may still be opened.
+	 * Instead, the inode has been added to orphan lists and the orphan
+	 * subsystem will take further care about it.
+	 */
+	ino_key_init(c, &ino_key, inode->i_ino);
+	ino_offs = dent_offs + aligned_dlen;
+	err = ubifs_tnc_add(c, &ino_key, lnum, ino_offs, ilen);
+	if (err)
+		goto out_ro;
+
+	ino_key_init(c, &ino_key, dir->i_ino);
+	ino_offs += aligned_ilen;
+	err = ubifs_tnc_add(c, &ino_key, lnum, ino_offs, UBIFS_INO_NODE_SZ);
+	if (err)
+		goto out_ro;
+
+	finish_reservation(c);
+	spin_lock(&ui->ui_lock);
+	ui->synced_i_size = ui->ui_size;
+	spin_unlock(&ui->ui_lock);
+	mark_inode_clean(c, ui);
+	mark_inode_clean(c, dir_ui);
+	return 0;
+
+out_finish:
+	finish_reservation(c);
+out_free:
+	kfree(dent);
+	return err;
+
+out_release:
+	release_head(c, BASEHD);
+out_ro:
+	ubifs_ro_mode(c, err);
+	if (last_reference)
+		ubifs_delete_orphan(c, inode->i_ino);
+	finish_reservation(c);
+	return err;
+}
+
+/**
+ * ubifs_jnl_write_data - write a data node to the journal.
+ * @c: UBIFS file-system description object
+ * @inode: inode the data node belongs to
+ * @key: node key
+ * @buf: buffer to write
+ * @len: data length (must not exceed %UBIFS_BLOCK_SIZE)
+ *
+ * This function writes a data node to the journal. Returns %0 if the data node
+ * was successfully written, and a negative error code in case of failure.
+ */
+int ubifs_jnl_write_data(struct ubifs_info *c, const struct inode *inode,
+			 const union ubifs_key *key, const void *buf, int len)
+{
+	struct ubifs_data_node *data;
+	int err, lnum, offs, compr_type, out_len;
+	int dlen = UBIFS_DATA_NODE_SZ + UBIFS_BLOCK_SIZE * WORST_COMPR_FACTOR;
+	struct ubifs_inode *ui = ubifs_inode(inode);
+
+	dbg_jnl("ino %lu, blk %u, len %d, key %s", key_inum(c, key),
+		key_block(c, key), len, DBGKEY(key));
+	ubifs_assert(len <= UBIFS_BLOCK_SIZE);
+
+	data = kmalloc(dlen, GFP_NOFS);
+	if (!data)
+		return -ENOMEM;
+
+	data->ch.node_type = UBIFS_DATA_NODE;
+	key_write(c, key, &data->key);
+	data->size = cpu_to_le32(len);
+	zero_data_node_unused(data);
+
+	if (!(ui->flags && UBIFS_COMPR_FL))
+		/* Compression is disabled for this inode */
+		compr_type = UBIFS_COMPR_NONE;
+	else
+		compr_type = ui->compr_type;
+
+	out_len = dlen - UBIFS_DATA_NODE_SZ;
+	ubifs_compress(buf, len, &data->data, &out_len, &compr_type);
+	ubifs_assert(out_len <= UBIFS_BLOCK_SIZE);
+
+	dlen = UBIFS_DATA_NODE_SZ + out_len;
+	data->compr_type = cpu_to_le16(compr_type);
+
+	/* Make reservation before allocating sequence numbers */
+	err = make_reservation(c, DATAHD, dlen);
+	if (err)
+		goto out_free;
+
+	err = write_node(c, DATAHD, data, dlen, &lnum, &offs);
+	if (err)
+		goto out_release;
+	ubifs_wbuf_add_ino_nolock(&c->jheads[DATAHD].wbuf, key_inum(c, key));
+	release_head(c, DATAHD);
+
+	err = ubifs_tnc_add(c, key, lnum, offs, dlen);
+	if (err)
+		goto out_ro;
+
+	finish_reservation(c);
+	kfree(data);
+	return 0;
+
+out_release:
+	release_head(c, DATAHD);
+out_ro:
+	ubifs_ro_mode(c, err);
+	finish_reservation(c);
+out_free:
+	kfree(data);
+	return err;
+}
+
+/**
+ * ubifs_jnl_write_inode - flush inode to the journal.
+ * @c: UBIFS file-system description object
+ * @inode: inode to flush
+ * @deletion: inode has been deleted
+ *
+ * This function writes inode @inode to the journal. If the inode is
+ * synchronous, it also synchronizes the write-buffer. Returns zero in case of
+ * success and a negative error code in case of failure.
+ */
+int ubifs_jnl_write_inode(struct ubifs_info *c, const struct inode *inode,
+			  int deletion)
+{
+	int err, len, lnum, offs, sync = 0;
+	struct ubifs_ino_node *ino;
+	struct ubifs_inode *ui = ubifs_inode(inode);
+
+	dbg_jnl("ino %lu%s", inode->i_ino,
+		deletion ? " (last reference)" : "");
+	if (deletion)
+		ubifs_assert(inode->i_nlink == 0);
+
+	len = UBIFS_INO_NODE_SZ;
+	/*
+	 * If the inode is being deleted, do not write the attached data. No
+	 * need to synchronize the write-buffer either.
+	 */
+	if (!deletion) {
+		len += ui->data_len;
+		sync = IS_SYNC(inode);
+	}
+	ino = kmalloc(len, GFP_NOFS);
+	if (!ino)
+		return -ENOMEM;
+
+	/* Make reservation before allocating sequence numbers */
+	err = make_reservation(c, BASEHD, len);
+	if (err)
+		goto out_free;
+
+	pack_inode(c, ino, inode, 1, deletion);
+	err = write_head(c, BASEHD, ino, len, &lnum, &offs, sync);
+	if (err)
+		goto out_release;
+	if (!sync)
+		ubifs_wbuf_add_ino_nolock(&c->jheads[BASEHD].wbuf,
+					  inode->i_ino);
+	release_head(c, BASEHD);
+
+	if (deletion) {
+		err = ubifs_tnc_remove_ino(c, inode->i_ino);
+		if (err)
+			goto out_ro;
+		ubifs_delete_orphan(c, inode->i_ino);
+		err = ubifs_add_dirt(c, lnum, len);
+	} else {
+		union ubifs_key key;
+
+		ino_key_init(c, &key, inode->i_ino);
+		err = ubifs_tnc_add(c, &key, lnum, offs, len);
+	}
+	if (err)
+		goto out_ro;
+
+	finish_reservation(c);
+	spin_lock(&ui->ui_lock);
+	ui->synced_i_size = ui->ui_size;
+	spin_unlock(&ui->ui_lock);
+	kfree(ino);
+	return 0;
+
+out_release:
+	release_head(c, BASEHD);
+out_ro:
+	ubifs_ro_mode(c, err);
+	finish_reservation(c);
+out_free:
+	kfree(ino);
+	return err;
+}
+
+/**
+ * ubifs_jnl_rename - rename a directory entry.
+ * @c: UBIFS file-system description object
+ * @old_dir: parent inode of directory entry to rename
+ * @old_dentry: directory entry to rename
+ * @new_dir: parent inode of directory entry to rename
+ * @new_dentry: new directory entry (or directory entry to replace)
+ * @sync: non-zero if the write-buffer has to be synchronized
+ *
+ * This function implements the re-name operation which may involve writing up
+ * to 3 inodes and 2 directory entries. It marks the written inodes as clean
+ * and returns zero on success. In case of failure, a negative error code is
+ * returned.
+ */
+int ubifs_jnl_rename(struct ubifs_info *c, const struct inode *old_dir,
+		     const struct dentry *old_dentry,
+		     const struct inode *new_dir,
+		     const struct dentry *new_dentry, int sync)
+{
+	void *p;
+	union ubifs_key key;
+	struct ubifs_dent_node *dent, *dent2;
+	int err, dlen1, dlen2, ilen, lnum, offs, len;
+	const struct inode *old_inode = old_dentry->d_inode;
+	const struct inode *new_inode = new_dentry->d_inode;
+	int aligned_dlen1, aligned_dlen2, plen = UBIFS_INO_NODE_SZ;
+	int last_reference = !!(new_inode && new_inode->i_nlink == 0);
+	int move = (old_dir != new_dir);
+	struct ubifs_inode *uninitialized_var(new_ui);
+
+	dbg_jnl("dent '%.*s' in dir ino %lu to dent '%.*s' in dir ino %lu",
+		old_dentry->d_name.len, old_dentry->d_name.name,
+		old_dir->i_ino, new_dentry->d_name.len,
+		new_dentry->d_name.name, new_dir->i_ino);
+	ubifs_assert(ubifs_inode(old_dir)->data_len == 0);
+	ubifs_assert(ubifs_inode(new_dir)->data_len == 0);
+	ubifs_assert(mutex_is_locked(&ubifs_inode(old_dir)->ui_mutex));
+	ubifs_assert(mutex_is_locked(&ubifs_inode(new_dir)->ui_mutex));
+
+	dlen1 = UBIFS_DENT_NODE_SZ + new_dentry->d_name.len + 1;
+	dlen2 = UBIFS_DENT_NODE_SZ + old_dentry->d_name.len + 1;
+	if (new_inode) {
+		new_ui = ubifs_inode(new_inode);
+		ubifs_assert(mutex_is_locked(&new_ui->ui_mutex));
+		ilen = UBIFS_INO_NODE_SZ;
+		if (!last_reference)
+			ilen += new_ui->data_len;
+	} else
+		ilen = 0;
+
+	aligned_dlen1 = ALIGN(dlen1, 8);
+	aligned_dlen2 = ALIGN(dlen2, 8);
+	len = aligned_dlen1 + aligned_dlen2 + ALIGN(ilen, 8) + ALIGN(plen, 8);
+	if (old_dir != new_dir)
+		len += plen;
+	dent = kmalloc(len, GFP_NOFS);
+	if (!dent)
+		return -ENOMEM;
+
+	/* Make reservation before allocating sequence numbers */
+	err = make_reservation(c, BASEHD, len);
+	if (err)
+		goto out_free;
+
+	/* Make new dent */
+	dent->ch.node_type = UBIFS_DENT_NODE;
+	dent_key_init_flash(c, &dent->key, new_dir->i_ino, &new_dentry->d_name);
+	dent->inum = cpu_to_le64(old_inode->i_ino);
+	dent->type = get_dent_type(old_inode->i_mode);
+	dent->nlen = cpu_to_le16(new_dentry->d_name.len);
+	memcpy(dent->name, new_dentry->d_name.name, new_dentry->d_name.len);
+	dent->name[new_dentry->d_name.len] = '\0';
+	zero_dent_node_unused(dent);
+	ubifs_prep_grp_node(c, dent, dlen1, 0);
+
+	/* Make deletion dent */
+	dent2 = (void *)dent + aligned_dlen1;
+	dent2->ch.node_type = UBIFS_DENT_NODE;
+	dent_key_init_flash(c, &dent2->key, old_dir->i_ino,
+			    &old_dentry->d_name);
+	dent2->inum = 0;
+	dent2->type = DT_UNKNOWN;
+	dent2->nlen = cpu_to_le16(old_dentry->d_name.len);
+	memcpy(dent2->name, old_dentry->d_name.name, old_dentry->d_name.len);
+	dent2->name[old_dentry->d_name.len] = '\0';
+	zero_dent_node_unused(dent2);
+	ubifs_prep_grp_node(c, dent2, dlen2, 0);
+
+	p = (void *)dent2 + aligned_dlen2;
+	if (new_inode) {
+		pack_inode(c, p, new_inode, 0, last_reference);
+		p += ALIGN(ilen, 8);
+	}
+
+	if (!move)
+		pack_inode(c, p, old_dir, 1, 0);
+	else {
+		pack_inode(c, p, old_dir, 0, 0);
+		p += ALIGN(plen, 8);
+		pack_inode(c, p, new_dir, 1, 0);
+	}
+
+	if (last_reference) {
+		err = ubifs_add_orphan(c, new_inode->i_ino);
+		if (err) {
+			release_head(c, BASEHD);
+			goto out_finish;
+		}
+	}
+
+	err = write_head(c, BASEHD, dent, len, &lnum, &offs, sync);
+	if (err)
+		goto out_release;
+	if (!sync) {
+		struct ubifs_wbuf *wbuf = &c->jheads[BASEHD].wbuf;
+
+		ubifs_wbuf_add_ino_nolock(wbuf, new_dir->i_ino);
+		ubifs_wbuf_add_ino_nolock(wbuf, old_dir->i_ino);
+		if (new_inode)
+			ubifs_wbuf_add_ino_nolock(&c->jheads[BASEHD].wbuf,
+						  new_inode->i_ino);
+	}
+	release_head(c, BASEHD);
+
+	dent_key_init(c, &key, new_dir->i_ino, &new_dentry->d_name);
+	err = ubifs_tnc_add_nm(c, &key, lnum, offs, dlen1, &new_dentry->d_name);
+	if (err)
+		goto out_ro;
+
+	err = ubifs_add_dirt(c, lnum, dlen2);
+	if (err)
+		goto out_ro;
+
+	dent_key_init(c, &key, old_dir->i_ino, &old_dentry->d_name);
+	err = ubifs_tnc_remove_nm(c, &key, &old_dentry->d_name);
+	if (err)
+		goto out_ro;
+
+	offs += aligned_dlen1 + aligned_dlen2;
+	if (new_inode) {
+		ino_key_init(c, &key, new_inode->i_ino);
+		err = ubifs_tnc_add(c, &key, lnum, offs, ilen);
+		if (err)
+			goto out_ro;
+		offs += ALIGN(ilen, 8);
+	}
+
+	ino_key_init(c, &key, old_dir->i_ino);
+	err = ubifs_tnc_add(c, &key, lnum, offs, plen);
+	if (err)
+		goto out_ro;
+
+	if (old_dir != new_dir) {
+		offs += ALIGN(plen, 8);
+		ino_key_init(c, &key, new_dir->i_ino);
+		err = ubifs_tnc_add(c, &key, lnum, offs, plen);
+		if (err)
+			goto out_ro;
+	}
+
+	finish_reservation(c);
+	if (new_inode) {
+		mark_inode_clean(c, new_ui);
+		spin_lock(&new_ui->ui_lock);
+		new_ui->synced_i_size = new_ui->ui_size;
+		spin_unlock(&new_ui->ui_lock);
+	}
+	mark_inode_clean(c, ubifs_inode(old_dir));
+	if (move)
+		mark_inode_clean(c, ubifs_inode(new_dir));
+	kfree(dent);
+	return 0;
+
+out_release:
+	release_head(c, BASEHD);
+out_ro:
+	ubifs_ro_mode(c, err);
+	if (last_reference)
+		ubifs_delete_orphan(c, new_inode->i_ino);
+out_finish:
+	finish_reservation(c);
+out_free:
+	kfree(dent);
+	return err;
+}
+
+/**
+ * recomp_data_node - re-compress a truncated data node.
+ * @dn: data node to re-compress
+ * @new_len: new length
+ *
+ * This function is used when an inode is truncated and the last data node of
+ * the inode has to be re-compressed and re-written.
+ */
+static int recomp_data_node(struct ubifs_data_node *dn, int *new_len)
+{
+	void *buf;
+	int err, len, compr_type, out_len;
+
+	out_len = le32_to_cpu(dn->size);
+	buf = kmalloc(out_len * WORST_COMPR_FACTOR, GFP_NOFS);
+	if (!buf)
+		return -ENOMEM;
+
+	len = le32_to_cpu(dn->ch.len) - UBIFS_DATA_NODE_SZ;
+	compr_type = le16_to_cpu(dn->compr_type);
+	err = ubifs_decompress(&dn->data, len, buf, &out_len, compr_type);
+	if (err)
+		goto out;
+
+	ubifs_compress(buf, *new_len, &dn->data, &out_len, &compr_type);
+	ubifs_assert(out_len <= UBIFS_BLOCK_SIZE);
+	dn->compr_type = cpu_to_le16(compr_type);
+	dn->size = cpu_to_le32(*new_len);
+	*new_len = UBIFS_DATA_NODE_SZ + out_len;
+out:
+	kfree(buf);
+	return err;
+}
+
+/**
+ * ubifs_jnl_truncate - update the journal for a truncation.
+ * @c: UBIFS file-system description object
+ * @inode: inode to truncate
+ * @old_size: old size
+ * @new_size: new size
+ *
+ * When the size of a file decreases due to truncation, a truncation node is
+ * written, the journal tree is updated, and the last data block is re-written
+ * if it has been affected. The inode is also updated in order to synchronize
+ * the new inode size.
+ *
+ * This function marks the inode as clean and returns zero on success. In case
+ * of failure, a negative error code is returned.
+ */
+int ubifs_jnl_truncate(struct ubifs_info *c, const struct inode *inode,
+		       loff_t old_size, loff_t new_size)
+{
+	union ubifs_key key, to_key;
+	struct ubifs_ino_node *ino;
+	struct ubifs_trun_node *trun;
+	struct ubifs_data_node *uninitialized_var(dn);
+	int err, dlen, len, lnum, offs, bit, sz, sync = IS_SYNC(inode);
+	struct ubifs_inode *ui = ubifs_inode(inode);
+	ino_t inum = inode->i_ino;
+	unsigned int blk;
+
+	dbg_jnl("ino %lu, size %lld -> %lld", inum, old_size, new_size);
+	ubifs_assert(!ui->data_len);
+	ubifs_assert(S_ISREG(inode->i_mode));
+	ubifs_assert(mutex_is_locked(&ui->ui_mutex));
+
+	sz = UBIFS_TRUN_NODE_SZ + UBIFS_INO_NODE_SZ +
+	     UBIFS_MAX_DATA_NODE_SZ * WORST_COMPR_FACTOR;
+	ino = kmalloc(sz, GFP_NOFS);
+	if (!ino)
+		return -ENOMEM;
+
+	trun = (void *)ino + UBIFS_INO_NODE_SZ;
+	trun->ch.node_type = UBIFS_TRUN_NODE;
+	trun->inum = cpu_to_le32(inum);
+	trun->old_size = cpu_to_le64(old_size);
+	trun->new_size = cpu_to_le64(new_size);
+	zero_trun_node_unused(trun);
+
+	dlen = new_size & (UBIFS_BLOCK_SIZE - 1);
+	if (dlen) {
+		/* Get last data block so it can be truncated */
+		dn = (void *)trun + UBIFS_TRUN_NODE_SZ;
+		blk = new_size >> UBIFS_BLOCK_SHIFT;
+		data_key_init(c, &key, inum, blk);
+		dbg_jnl("last block key %s", DBGKEY(&key));
+		err = ubifs_tnc_lookup(c, &key, dn);
+		if (err == -ENOENT)
+			dlen = 0; /* Not found (so it is a hole) */
+		else if (err)
+			goto out_free;
+		else {
+			if (le32_to_cpu(dn->size) <= dlen)
+				dlen = 0; /* Nothing to do */
+			else {
+				int compr_type = le16_to_cpu(dn->compr_type);
+
+				if (compr_type != UBIFS_COMPR_NONE) {
+					err = recomp_data_node(dn, &dlen);
+					if (err)
+						goto out_free;
+				} else {
+					dn->size = cpu_to_le32(dlen);
+					dlen += UBIFS_DATA_NODE_SZ;
+				}
+				zero_data_node_unused(dn);
+			}
+		}
+	}
+
+	/* Must make reservation before allocating sequence numbers */
+	len = UBIFS_TRUN_NODE_SZ + UBIFS_INO_NODE_SZ;
+	if (dlen)
+		len += dlen;
+	err = make_reservation(c, BASEHD, len);
+	if (err)
+		goto out_free;
+
+	pack_inode(c, ino, inode, 0, 0);
+	ubifs_prep_grp_node(c, trun, UBIFS_TRUN_NODE_SZ, dlen ? 0 : 1);
+	if (dlen)
+		ubifs_prep_grp_node(c, dn, dlen, 1);
+
+	err = write_head(c, BASEHD, ino, len, &lnum, &offs, sync);
+	if (err)
+		goto out_release;
+	if (!sync)
+		ubifs_wbuf_add_ino_nolock(&c->jheads[BASEHD].wbuf, inum);
+	release_head(c, BASEHD);
+
+	if (dlen) {
+		sz = offs + UBIFS_INO_NODE_SZ + UBIFS_TRUN_NODE_SZ;
+		err = ubifs_tnc_add(c, &key, lnum, sz, dlen);
+		if (err)
+			goto out_ro;
+	}
+
+	ino_key_init(c, &key, inum);
+	err = ubifs_tnc_add(c, &key, lnum, offs, UBIFS_INO_NODE_SZ);
+	if (err)
+		goto out_ro;
+
+	err = ubifs_add_dirt(c, lnum, UBIFS_TRUN_NODE_SZ);
+	if (err)
+		goto out_ro;
+
+	bit = new_size & (UBIFS_BLOCK_SIZE - 1);
+	blk = (new_size >> UBIFS_BLOCK_SHIFT) + (bit ? 1 : 0);
+	data_key_init(c, &key, inum, blk);
+
+	bit = old_size & (UBIFS_BLOCK_SIZE - 1);
+	blk = (old_size >> UBIFS_BLOCK_SHIFT) - (bit ? 0: 1);
+	data_key_init(c, &to_key, inum, blk);
+
+	err = ubifs_tnc_remove_range(c, &key, &to_key);
+	if (err)
+		goto out_ro;
+
+	finish_reservation(c);
+	spin_lock(&ui->ui_lock);
+	ui->synced_i_size = ui->ui_size;
+	spin_unlock(&ui->ui_lock);
+	mark_inode_clean(c, ui);
+	kfree(ino);
+	return 0;
+
+out_release:
+	release_head(c, BASEHD);
+out_ro:
+	ubifs_ro_mode(c, err);
+	finish_reservation(c);
+out_free:
+	kfree(ino);
+	return err;
+}
+
+#ifdef CONFIG_UBIFS_FS_XATTR
+
+/**
+ * ubifs_jnl_delete_xattr - delete an extended attribute.
+ * @c: UBIFS file-system description object
+ * @host: host inode
+ * @inode: extended attribute inode
+ * @nm: extended attribute entry name
+ *
+ * This function delete an extended attribute which is very similar to
+ * un-linking regular files - it writes a deletion xentry, a deletion inode and
+ * updates the target inode. Returns zero in case of success and a negative
+ * error code in case of failure.
+ */
+int ubifs_jnl_delete_xattr(struct ubifs_info *c, const struct inode *host,
+			   const struct inode *inode, const struct qstr *nm)
+{
+	int err, xlen, hlen, len, lnum, xent_offs, aligned_xlen;
+	struct ubifs_dent_node *xent;
+	struct ubifs_ino_node *ino;
+	union ubifs_key xent_key, key1, key2;
+	int sync = IS_DIRSYNC(host);
+	struct ubifs_inode *host_ui = ubifs_inode(host);
+
+	dbg_jnl("host %lu, xattr ino %lu, name '%s', data len %d",
+		host->i_ino, inode->i_ino, nm->name,
+		ubifs_inode(inode)->data_len);
+	ubifs_assert(inode->i_nlink == 0);
+	ubifs_assert(mutex_is_locked(&host_ui->ui_mutex));
+
+	/*
+	 * Since we are deleting the inode, we do not bother to attach any data
+	 * to it and assume its length is %UBIFS_INO_NODE_SZ.
+	 */
+	xlen = UBIFS_DENT_NODE_SZ + nm->len + 1;
+	aligned_xlen = ALIGN(xlen, 8);
+	hlen = host_ui->data_len + UBIFS_INO_NODE_SZ;
+	len = aligned_xlen + UBIFS_INO_NODE_SZ + ALIGN(hlen, 8);
+
+	xent = kmalloc(len, GFP_NOFS);
+	if (!xent)
+		return -ENOMEM;
+
+	/* Make reservation before allocating sequence numbers */
+	err = make_reservation(c, BASEHD, len);
+	if (err) {
+		kfree(xent);
+		return err;
+	}
+
+	xent->ch.node_type = UBIFS_XENT_NODE;
+	xent_key_init(c, &xent_key, host->i_ino, nm);
+	key_write(c, &xent_key, xent->key);
+	xent->inum = 0;
+	xent->type = get_dent_type(inode->i_mode);
+	xent->nlen = cpu_to_le16(nm->len);
+	memcpy(xent->name, nm->name, nm->len);
+	xent->name[nm->len] = '\0';
+	zero_dent_node_unused(xent);
+	ubifs_prep_grp_node(c, xent, xlen, 0);
+
+	ino = (void *)xent + aligned_xlen;
+	pack_inode(c, ino, inode, 0, 1);
+	ino = (void *)ino + UBIFS_INO_NODE_SZ;
+	pack_inode(c, ino, host, 1, 0);
+
+	err = write_head(c, BASEHD, xent, len, &lnum, &xent_offs, sync);
+	if (!sync && !err)
+		ubifs_wbuf_add_ino_nolock(&c->jheads[BASEHD].wbuf, host->i_ino);
+	release_head(c, BASEHD);
+	kfree(xent);
+	if (err)
+		goto out_ro;
+
+	/* Remove the extended attribute entry from TNC */
+	err = ubifs_tnc_remove_nm(c, &xent_key, nm);
+	if (err)
+		goto out_ro;
+	err = ubifs_add_dirt(c, lnum, xlen);
+	if (err)
+		goto out_ro;
+
+	/*
+	 * Remove all nodes belonging to the extended attribute inode from TNC.
+	 * Well, there actually must be only one node - the inode itself.
+	 */
+	lowest_ino_key(c, &key1, inode->i_ino);
+	highest_ino_key(c, &key2, inode->i_ino);
+	err = ubifs_tnc_remove_range(c, &key1, &key2);
+	if (err)
+		goto out_ro;
+	err = ubifs_add_dirt(c, lnum, UBIFS_INO_NODE_SZ);
+	if (err)
+		goto out_ro;
+
+	/* And update TNC with the new host inode position */
+	ino_key_init(c, &key1, host->i_ino);
+	err = ubifs_tnc_add(c, &key1, lnum, xent_offs + len - hlen, hlen);
+	if (err)
+		goto out_ro;
+
+	finish_reservation(c);
+	spin_lock(&host_ui->ui_lock);
+	host_ui->synced_i_size = host_ui->ui_size;
+	spin_unlock(&host_ui->ui_lock);
+	mark_inode_clean(c, host_ui);
+	return 0;
+
+out_ro:
+	ubifs_ro_mode(c, err);
+	finish_reservation(c);
+	return err;
+}
+
+/**
+ * ubifs_jnl_change_xattr - change an extended attribute.
+ * @c: UBIFS file-system description object
+ * @inode: extended attribute inode
+ * @host: host inode
+ *
+ * This function writes the updated version of an extended attribute inode and
+ * the host inode tho the journal (to the base head). The host inode is written
+ * after the extended attribute inode in order to guarantee that the extended
+ * attribute will be flushed when the inode is synchronized by 'fsync()' and
+ * consequently, the write-buffer is synchronized. This function returns zero
+ * in case of success and a negative error code in case of failure.
+ */
+int ubifs_jnl_change_xattr(struct ubifs_info *c, const struct inode *inode,
+			   const struct inode *host)
+{
+	int err, len1, len2, aligned_len, aligned_len1, lnum, offs;
+	struct ubifs_inode *host_ui = ubifs_inode(inode);
+	struct ubifs_ino_node *ino;
+	union ubifs_key key;
+	int sync = IS_DIRSYNC(host);
+
+	dbg_jnl("ino %lu, ino %lu", host->i_ino, inode->i_ino);
+	ubifs_assert(host->i_nlink > 0);
+	ubifs_assert(inode->i_nlink > 0);
+	ubifs_assert(mutex_is_locked(&host_ui->ui_mutex));
+
+	len1 = UBIFS_INO_NODE_SZ + host_ui->data_len;
+	len2 = UBIFS_INO_NODE_SZ + ubifs_inode(inode)->data_len;
+	aligned_len1 = ALIGN(len1, 8);
+	aligned_len = aligned_len1 + ALIGN(len2, 8);
+
+	ino = kmalloc(aligned_len, GFP_NOFS);
+	if (!ino)
+		return -ENOMEM;
+
+	/* Make reservation before allocating sequence numbers */
+	err = make_reservation(c, BASEHD, aligned_len);
+	if (err)
+		goto out_free;
+
+	pack_inode(c, ino, host, 0, 0);
+	pack_inode(c, (void *)ino + aligned_len1, inode, 1, 0);
+
+	err = write_head(c, BASEHD, ino, aligned_len, &lnum, &offs, 0);
+	if (!sync && !err) {
+		struct ubifs_wbuf *wbuf = &c->jheads[BASEHD].wbuf;
+
+		ubifs_wbuf_add_ino_nolock(wbuf, host->i_ino);
+		ubifs_wbuf_add_ino_nolock(wbuf, inode->i_ino);
+	}
+	release_head(c, BASEHD);
+	if (err)
+		goto out_ro;
+
+	ino_key_init(c, &key, host->i_ino);
+	err = ubifs_tnc_add(c, &key, lnum, offs, len1);
+	if (err)
+		goto out_ro;
+
+	ino_key_init(c, &key, inode->i_ino);
+	err = ubifs_tnc_add(c, &key, lnum, offs + aligned_len1, len2);
+	if (err)
+		goto out_ro;
+
+	finish_reservation(c);
+	spin_lock(&host_ui->ui_lock);
+	host_ui->synced_i_size = host_ui->ui_size;
+	spin_unlock(&host_ui->ui_lock);
+	mark_inode_clean(c, host_ui);
+	kfree(ino);
+	return 0;
+
+out_ro:
+	ubifs_ro_mode(c, err);
+	finish_reservation(c);
+out_free:
+	kfree(ino);
+	return err;
+}
+
+#endif /* CONFIG_UBIFS_FS_XATTR */
diff --git a/fs/ubifs/key.h b/fs/ubifs/key.h
new file mode 100644
index 00000000000..8f747600754
--- /dev/null
+++ b/fs/ubifs/key.h
@@ -0,0 +1,533 @@
+/*
+ * This file is part of UBIFS.
+ *
+ * Copyright (C) 2006-2008 Nokia Corporation.
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 as published by
+ * the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
+ * more details.
+ *
+ * You should have received a copy of the GNU General Public License along with
+ * this program; if not, write to the Free Software Foundation, Inc., 51
+ * Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
+ *
+ * Authors: Artem Bityutskiy (Битюцкий Артём)
+ *          Adrian Hunter
+ */
+
+/*
+ * This header contains various key-related definitions and helper function.
+ * UBIFS allows several key schemes, so we access key fields only via these
+ * helpers. At the moment only one key scheme is supported.
+ *
+ * Simple key scheme
+ * ~~~~~~~~~~~~~~~~~
+ *
+ * Keys are 64-bits long. First 32-bits are inode number (parent inode number
+ * in case of direntry key). Next 3 bits are node type. The last 29 bits are
+ * 4KiB offset in case of inode node, and direntry hash in case of a direntry
+ * node. We use "r5" hash borrowed from reiserfs.
+ */
+
+#ifndef __UBIFS_KEY_H__
+#define __UBIFS_KEY_H__
+
+/**
+ * key_r5_hash - R5 hash function (borrowed from reiserfs).
+ * @s: direntry name
+ * @len: name length
+ */
+static inline uint32_t key_r5_hash(const char *s, int len)
+{
+	uint32_t a = 0;
+	const signed char *str = (const signed char *)s;
+
+	while (*str) {
+		a += *str << 4;
+		a += *str >> 4;
+		a *= 11;
+		str++;
+	}
+
+	a &= UBIFS_S_KEY_HASH_MASK;
+
+	/*
+	 * We use hash values as offset in directories, so values %0 and %1 are
+	 * reserved for "." and "..". %2 is reserved for "end of readdir"
+	 * marker.
+	 */
+	if (unlikely(a >= 0 && a <= 2))
+		a += 3;
+	return a;
+}
+
+/**
+ * key_test_hash - testing hash function.
+ * @str: direntry name
+ * @len: name length
+ */
+static inline uint32_t key_test_hash(const char *str, int len)
+{
+	uint32_t a = 0;
+
+	len = min_t(uint32_t, len, 4);
+	memcpy(&a, str, len);
+	a &= UBIFS_S_KEY_HASH_MASK;
+	if (unlikely(a >= 0 && a <= 2))
+		a += 3;
+	return a;
+}
+
+/**
+ * ino_key_init - initialize inode key.
+ * @c: UBIFS file-system description object
+ * @key: key to initialize
+ * @inum: inode number
+ */
+static inline void ino_key_init(const struct ubifs_info *c,
+				union ubifs_key *key, ino_t inum)
+{
+	key->u32[0] = inum;
+	key->u32[1] = UBIFS_INO_KEY << UBIFS_S_KEY_BLOCK_BITS;
+}
+
+/**
+ * ino_key_init_flash - initialize on-flash inode key.
+ * @c: UBIFS file-system description object
+ * @k: key to initialize
+ * @inum: inode number
+ */
+static inline void ino_key_init_flash(const struct ubifs_info *c, void *k,
+				      ino_t inum)
+{
+	union ubifs_key *key = k;
+
+	key->j32[0] = cpu_to_le32(inum);
+	key->j32[1] = cpu_to_le32(UBIFS_INO_KEY << UBIFS_S_KEY_BLOCK_BITS);
+	memset(k + 8, 0, UBIFS_MAX_KEY_LEN - 8);
+}
+
+/**
+ * lowest_ino_key - get the lowest possible inode key.
+ * @c: UBIFS file-system description object
+ * @key: key to initialize
+ * @inum: inode number
+ */
+static inline void lowest_ino_key(const struct ubifs_info *c,
+				union ubifs_key *key, ino_t inum)
+{
+	key->u32[0] = inum;
+	key->u32[1] = 0;
+}
+
+/**
+ * highest_ino_key - get the highest possible inode key.
+ * @c: UBIFS file-system description object
+ * @key: key to initialize
+ * @inum: inode number
+ */
+static inline void highest_ino_key(const struct ubifs_info *c,
+				union ubifs_key *key, ino_t inum)
+{
+	key->u32[0] = inum;
+	key->u32[1] = 0xffffffff;
+}
+
+/**
+ * dent_key_init - initialize directory entry key.
+ * @c: UBIFS file-system description object
+ * @key: key to initialize
+ * @inum: parent inode number
+ * @nm: direntry name and length
+ */
+static inline void dent_key_init(const struct ubifs_info *c,
+				 union ubifs_key *key, ino_t inum,
+				 const struct qstr *nm)
+{
+	uint32_t hash = c->key_hash(nm->name, nm->len);
+
+	ubifs_assert(!(hash & ~UBIFS_S_KEY_HASH_MASK));
+	key->u32[0] = inum;
+	key->u32[1] = hash | (UBIFS_DENT_KEY << UBIFS_S_KEY_HASH_BITS);
+}
+
+/**
+ * dent_key_init_hash - initialize directory entry key without re-calculating
+ *                      hash function.
+ * @c: UBIFS file-system description object
+ * @key: key to initialize
+ * @inum: parent inode number
+ * @hash: direntry name hash
+ */
+static inline void dent_key_init_hash(const struct ubifs_info *c,
+				      union ubifs_key *key, ino_t inum,
+				      uint32_t hash)
+{
+	ubifs_assert(!(hash & ~UBIFS_S_KEY_HASH_MASK));
+	key->u32[0] = inum;
+	key->u32[1] = hash | (UBIFS_DENT_KEY << UBIFS_S_KEY_HASH_BITS);
+}
+
+/**
+ * dent_key_init_flash - initialize on-flash directory entry key.
+ * @c: UBIFS file-system description object
+ * @k: key to initialize
+ * @inum: parent inode number
+ * @nm: direntry name and length
+ */
+static inline void dent_key_init_flash(const struct ubifs_info *c, void *k,
+				       ino_t inum, const struct qstr *nm)
+{
+	union ubifs_key *key = k;
+	uint32_t hash = c->key_hash(nm->name, nm->len);
+
+	ubifs_assert(!(hash & ~UBIFS_S_KEY_HASH_MASK));
+	key->j32[0] = cpu_to_le32(inum);
+	key->j32[1] = cpu_to_le32(hash |
+				  (UBIFS_DENT_KEY << UBIFS_S_KEY_HASH_BITS));
+	memset(k + 8, 0, UBIFS_MAX_KEY_LEN - 8);
+}
+
+/**
+ * lowest_dent_key - get the lowest possible directory entry key.
+ * @c: UBIFS file-system description object
+ * @key: where to store the lowest key
+ * @inum: parent inode number
+ */
+static inline void lowest_dent_key(const struct ubifs_info *c,
+				   union ubifs_key *key, ino_t inum)
+{
+	key->u32[0] = inum;
+	key->u32[1] = UBIFS_DENT_KEY << UBIFS_S_KEY_HASH_BITS;
+}
+
+/**
+ * xent_key_init - initialize extended attribute entry key.
+ * @c: UBIFS file-system description object
+ * @key: key to initialize
+ * @inum: host inode number
+ * @nm: extended attribute entry name and length
+ */
+static inline void xent_key_init(const struct ubifs_info *c,
+				 union ubifs_key *key, ino_t inum,
+				 const struct qstr *nm)
+{
+	uint32_t hash = c->key_hash(nm->name, nm->len);
+
+	ubifs_assert(!(hash & ~UBIFS_S_KEY_HASH_MASK));
+	key->u32[0] = inum;
+	key->u32[1] = hash | (UBIFS_XENT_KEY << UBIFS_S_KEY_HASH_BITS);
+}
+
+/**
+ * xent_key_init_hash - initialize extended attribute entry key without
+ *                      re-calculating hash function.
+ * @c: UBIFS file-system description object
+ * @key: key to initialize
+ * @inum: host inode number
+ * @hash: extended attribute entry name hash
+ */
+static inline void xent_key_init_hash(const struct ubifs_info *c,
+				      union ubifs_key *key, ino_t inum,
+				      uint32_t hash)
+{
+	ubifs_assert(!(hash & ~UBIFS_S_KEY_HASH_MASK));
+	key->u32[0] = inum;
+	key->u32[1] = hash | (UBIFS_XENT_KEY << UBIFS_S_KEY_HASH_BITS);
+}
+
+/**
+ * xent_key_init_flash - initialize on-flash extended attribute entry key.
+ * @c: UBIFS file-system description object
+ * @k: key to initialize
+ * @inum: host inode number
+ * @nm: extended attribute entry name and length
+ */
+static inline void xent_key_init_flash(const struct ubifs_info *c, void *k,
+				       ino_t inum, const struct qstr *nm)
+{
+	union ubifs_key *key = k;
+	uint32_t hash = c->key_hash(nm->name, nm->len);
+
+	ubifs_assert(!(hash & ~UBIFS_S_KEY_HASH_MASK));
+	key->j32[0] = cpu_to_le32(inum);
+	key->j32[1] = cpu_to_le32(hash |
+				  (UBIFS_XENT_KEY << UBIFS_S_KEY_HASH_BITS));
+	memset(k + 8, 0, UBIFS_MAX_KEY_LEN - 8);
+}
+
+/**
+ * lowest_xent_key - get the lowest possible extended attribute entry key.
+ * @c: UBIFS file-system description object
+ * @key: where to store the lowest key
+ * @inum: host inode number
+ */
+static inline void lowest_xent_key(const struct ubifs_info *c,
+				   union ubifs_key *key, ino_t inum)
+{
+	key->u32[0] = inum;
+	key->u32[1] = UBIFS_XENT_KEY << UBIFS_S_KEY_HASH_BITS;
+}
+
+/**
+ * data_key_init - initialize data key.
+ * @c: UBIFS file-system description object
+ * @key: key to initialize
+ * @inum: inode number
+ * @block: block number
+ */
+static inline void data_key_init(const struct ubifs_info *c,
+				 union ubifs_key *key, ino_t inum,
+				 unsigned int block)
+{
+	ubifs_assert(!(block & ~UBIFS_S_KEY_BLOCK_MASK));
+	key->u32[0] = inum;
+	key->u32[1] = block | (UBIFS_DATA_KEY << UBIFS_S_KEY_BLOCK_BITS);
+}
+
+/**
+ * data_key_init_flash - initialize on-flash data key.
+ * @c: UBIFS file-system description object
+ * @k: key to initialize
+ * @inum: inode number
+ * @block: block number
+ */
+static inline void data_key_init_flash(const struct ubifs_info *c, void *k,
+				       ino_t inum, unsigned int block)
+{
+	union ubifs_key *key = k;
+
+	ubifs_assert(!(block & ~UBIFS_S_KEY_BLOCK_MASK));
+	key->j32[0] = cpu_to_le32(inum);
+	key->j32[1] = cpu_to_le32(block |
+				  (UBIFS_DATA_KEY << UBIFS_S_KEY_BLOCK_BITS));
+	memset(k + 8, 0, UBIFS_MAX_KEY_LEN - 8);
+}
+
+/**
+ * trun_key_init - initialize truncation node key.
+ * @c: UBIFS file-system description object
+ * @key: key to initialize
+ * @inum: inode number
+ *
+ * Note, UBIFS does not have truncation keys on the media and this function is
+ * only used for purposes of replay.
+ */
+static inline void trun_key_init(const struct ubifs_info *c,
+				 union ubifs_key *key, ino_t inum)
+{
+	key->u32[0] = inum;
+	key->u32[1] = UBIFS_TRUN_KEY << UBIFS_S_KEY_BLOCK_BITS;
+}
+
+/**
+ * key_type - get key type.
+ * @c: UBIFS file-system description object
+ * @key: key to get type of
+ */
+static inline int key_type(const struct ubifs_info *c,
+			   const union ubifs_key *key)
+{
+	return key->u32[1] >> UBIFS_S_KEY_BLOCK_BITS;
+}
+
+/**
+ * key_type_flash - get type of a on-flash formatted key.
+ * @c: UBIFS file-system description object
+ * @k: key to get type of
+ */
+static inline int key_type_flash(const struct ubifs_info *c, const void *k)
+{
+	const union ubifs_key *key = k;
+
+	return le32_to_cpu(key->u32[1]) >> UBIFS_S_KEY_BLOCK_BITS;
+}
+
+/**
+ * key_inum - fetch inode number from key.
+ * @c: UBIFS file-system description object
+ * @k: key to fetch inode number from
+ */
+static inline ino_t key_inum(const struct ubifs_info *c, const void *k)
+{
+	const union ubifs_key *key = k;
+
+	return key->u32[0];
+}
+
+/**
+ * key_inum_flash - fetch inode number from an on-flash formatted key.
+ * @c: UBIFS file-system description object
+ * @k: key to fetch inode number from
+ */
+static inline ino_t key_inum_flash(const struct ubifs_info *c, const void *k)
+{
+	const union ubifs_key *key = k;
+
+	return le32_to_cpu(key->j32[0]);
+}
+
+/**
+ * key_hash - get directory entry hash.
+ * @c: UBIFS file-system description object
+ * @key: the key to get hash from
+ */
+static inline int key_hash(const struct ubifs_info *c,
+			   const union ubifs_key *key)
+{
+	return key->u32[1] & UBIFS_S_KEY_HASH_MASK;
+}
+
+/**
+ * key_hash_flash - get directory entry hash from an on-flash formatted key.
+ * @c: UBIFS file-system description object
+ * @k: the key to get hash from
+ */
+static inline int key_hash_flash(const struct ubifs_info *c, const void *k)
+{
+	const union ubifs_key *key = k;
+
+	return le32_to_cpu(key->j32[1]) & UBIFS_S_KEY_HASH_MASK;
+}
+
+/**
+ * key_block - get data block number.
+ * @c: UBIFS file-system description object
+ * @key: the key to get the block number from
+ */
+static inline unsigned int key_block(const struct ubifs_info *c,
+				     const union ubifs_key *key)
+{
+	return key->u32[1] & UBIFS_S_KEY_BLOCK_MASK;
+}
+
+/**
+ * key_block_flash - get data block number from an on-flash formatted key.
+ * @c: UBIFS file-system description object
+ * @k: the key to get the block number from
+ */
+static inline unsigned int key_block_flash(const struct ubifs_info *c,
+					   const void *k)
+{
+	const union ubifs_key *key = k;
+
+	return le32_to_cpu(key->u32[1]) & UBIFS_S_KEY_BLOCK_MASK;
+}
+
+/**
+ * key_read - transform a key to in-memory format.
+ * @c: UBIFS file-system description object
+ * @from: the key to transform
+ * @to: the key to store the result
+ */
+static inline void key_read(const struct ubifs_info *c, const void *from,
+			    union ubifs_key *to)
+{
+	const union ubifs_key *f = from;
+
+	to->u32[0] = le32_to_cpu(f->j32[0]);
+	to->u32[1] = le32_to_cpu(f->j32[1]);
+}
+
+/**
+ * key_write - transform a key from in-memory format.
+ * @c: UBIFS file-system description object
+ * @from: the key to transform
+ * @to: the key to store the result
+ */
+static inline void key_write(const struct ubifs_info *c,
+			     const union ubifs_key *from, void *to)
+{
+	union ubifs_key *t = to;
+
+	t->j32[0] = cpu_to_le32(from->u32[0]);
+	t->j32[1] = cpu_to_le32(from->u32[1]);
+	memset(to + 8, 0, UBIFS_MAX_KEY_LEN - 8);
+}
+
+/**
+ * key_write_idx - transform a key from in-memory format for the index.
+ * @c: UBIFS file-system description object
+ * @from: the key to transform
+ * @to: the key to store the result
+ */
+static inline void key_write_idx(const struct ubifs_info *c,
+				 const union ubifs_key *from, void *to)
+{
+	union ubifs_key *t = to;
+
+	t->j32[0] = cpu_to_le32(from->u32[0]);
+	t->j32[1] = cpu_to_le32(from->u32[1]);
+}
+
+/**
+ * key_copy - copy a key.
+ * @c: UBIFS file-system description object
+ * @from: the key to copy from
+ * @to: the key to copy to
+ */
+static inline void key_copy(const struct ubifs_info *c,
+			    const union ubifs_key *from, union ubifs_key *to)
+{
+	to->u64[0] = from->u64[0];
+}
+
+/**
+ * keys_cmp - compare keys.
+ * @c: UBIFS file-system description object
+ * @key1: the first key to compare
+ * @key2: the second key to compare
+ *
+ * This function compares 2 keys and returns %-1 if @key1 is less than
+ * @key2, 0 if the keys are equivalent and %1 if @key1 is greater than @key2.
+ */
+static inline int keys_cmp(const struct ubifs_info *c,
+			   const union ubifs_key *key1,
+			   const union ubifs_key *key2)
+{
+	if (key1->u32[0] < key2->u32[0])
+		return -1;
+	if (key1->u32[0] > key2->u32[0])
+		return 1;
+	if (key1->u32[1] < key2->u32[1])
+		return -1;
+	if (key1->u32[1] > key2->u32[1])
+		return 1;
+
+	return 0;
+}
+
+/**
+ * is_hash_key - is a key vulnerable to hash collisions.
+ * @c: UBIFS file-system description object
+ * @key: key
+ *
+ * This function returns %1 if @key is a hashed key or %0 otherwise.
+ */
+static inline int is_hash_key(const struct ubifs_info *c,
+			      const union ubifs_key *key)
+{
+	int type = key_type(c, key);
+
+	return type == UBIFS_DENT_KEY || type == UBIFS_XENT_KEY;
+}
+
+/**
+ * key_max_inode_size - get maximum file size allowed by current key format.
+ * @c: UBIFS file-system description object
+ */
+static inline unsigned long long key_max_inode_size(const struct ubifs_info *c)
+{
+	switch (c->key_fmt) {
+	case UBIFS_SIMPLE_KEY_FMT:
+		return (1ULL << UBIFS_S_KEY_BLOCK_BITS) * UBIFS_BLOCK_SIZE;
+	default:
+		return 0;
+	}
+}
+#endif /* !__UBIFS_KEY_H__ */
diff --git a/fs/ubifs/log.c b/fs/ubifs/log.c
new file mode 100644
index 00000000000..36857b9ed59
--- /dev/null
+++ b/fs/ubifs/log.c
@@ -0,0 +1,805 @@
+/*
+ * This file is part of UBIFS.
+ *
+ * Copyright (C) 2006-2008 Nokia Corporation.
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 as published by
+ * the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
+ * more details.
+ *
+ * You should have received a copy of the GNU General Public License along with
+ * this program; if not, write to the Free Software Foundation, Inc., 51
+ * Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
+ *
+ * Authors: Artem Bityutskiy (Битюцкий Артём)
+ *          Adrian Hunter
+ */
+
+/*
+ * This file is a part of UBIFS journal implementation and contains various
+ * functions which manipulate the log. The log is a fixed area on the flash
+ * which does not contain any data but refers to buds. The log is a part of the
+ * journal.
+ */
+
+#include "ubifs.h"
+
+#ifdef CONFIG_UBIFS_FS_DEBUG
+static int dbg_check_bud_bytes(struct ubifs_info *c);
+#else
+#define dbg_check_bud_bytes(c) 0
+#endif
+
+/**
+ * ubifs_search_bud - search bud LEB.
+ * @c: UBIFS file-system description object
+ * @lnum: logical eraseblock number to search
+ *
+ * This function searches bud LEB @lnum. Returns bud description object in case
+ * of success and %NULL if there is no bud with this LEB number.
+ */
+struct ubifs_bud *ubifs_search_bud(struct ubifs_info *c, int lnum)
+{
+	struct rb_node *p;
+	struct ubifs_bud *bud;
+
+	spin_lock(&c->buds_lock);
+	p = c->buds.rb_node;
+	while (p) {
+		bud = rb_entry(p, struct ubifs_bud, rb);
+		if (lnum < bud->lnum)
+			p = p->rb_left;
+		else if (lnum > bud->lnum)
+			p = p->rb_right;
+		else {
+			spin_unlock(&c->buds_lock);
+			return bud;
+		}
+	}
+	spin_unlock(&c->buds_lock);
+	return NULL;
+}
+
+/**
+ * ubifs_get_wbuf - get the wbuf associated with a LEB, if there is one.
+ * @c: UBIFS file-system description object
+ * @lnum: logical eraseblock number to search
+ *
+ * This functions returns the wbuf for @lnum or %NULL if there is not one.
+ */
+struct ubifs_wbuf *ubifs_get_wbuf(struct ubifs_info *c, int lnum)
+{
+	struct rb_node *p;
+	struct ubifs_bud *bud;
+	int jhead;
+
+	if (!c->jheads)
+		return NULL;
+
+	spin_lock(&c->buds_lock);
+	p = c->buds.rb_node;
+	while (p) {
+		bud = rb_entry(p, struct ubifs_bud, rb);
+		if (lnum < bud->lnum)
+			p = p->rb_left;
+		else if (lnum > bud->lnum)
+			p = p->rb_right;
+		else {
+			jhead = bud->jhead;
+			spin_unlock(&c->buds_lock);
+			return &c->jheads[jhead].wbuf;
+		}
+	}
+	spin_unlock(&c->buds_lock);
+	return NULL;
+}
+
+/**
+ * next_log_lnum - switch to the next log LEB.
+ * @c: UBIFS file-system description object
+ * @lnum: current log LEB
+ */
+static inline int next_log_lnum(const struct ubifs_info *c, int lnum)
+{
+	lnum += 1;
+	if (lnum > c->log_last)
+		lnum = UBIFS_LOG_LNUM;
+
+	return lnum;
+}
+
+/**
+ * empty_log_bytes - calculate amount of empty space in the log.
+ * @c: UBIFS file-system description object
+ */
+static inline long long empty_log_bytes(const struct ubifs_info *c)
+{
+	long long h, t;
+
+	h = (long long)c->lhead_lnum * c->leb_size + c->lhead_offs;
+	t = (long long)c->ltail_lnum * c->leb_size;
+
+	if (h >= t)
+		return c->log_bytes - h + t;
+	else
+		return t - h;
+}
+
+/**
+ * ubifs_add_bud - add bud LEB to the tree of buds and its journal head list.
+ * @c: UBIFS file-system description object
+ * @bud: the bud to add
+ */
+void ubifs_add_bud(struct ubifs_info *c, struct ubifs_bud *bud)
+{
+	struct rb_node **p, *parent = NULL;
+	struct ubifs_bud *b;
+	struct ubifs_jhead *jhead;
+
+	spin_lock(&c->buds_lock);
+	p = &c->buds.rb_node;
+	while (*p) {
+		parent = *p;
+		b = rb_entry(parent, struct ubifs_bud, rb);
+		ubifs_assert(bud->lnum != b->lnum);
+		if (bud->lnum < b->lnum)
+			p = &(*p)->rb_left;
+		else
+			p = &(*p)->rb_right;
+	}
+
+	rb_link_node(&bud->rb, parent, p);
+	rb_insert_color(&bud->rb, &c->buds);
+	if (c->jheads) {
+		jhead = &c->jheads[bud->jhead];
+		list_add_tail(&bud->list, &jhead->buds_list);
+	} else
+		ubifs_assert(c->replaying && (c->vfs_sb->s_flags & MS_RDONLY));
+
+	/*
+	 * Note, although this is a new bud, we anyway account this space now,
+	 * before any data has been written to it, because this is about to
+	 * guarantee fixed mount time, and this bud will anyway be read and
+	 * scanned.
+	 */
+	c->bud_bytes += c->leb_size - bud->start;
+
+	dbg_log("LEB %d:%d, jhead %d, bud_bytes %lld", bud->lnum,
+		bud->start, bud->jhead, c->bud_bytes);
+	spin_unlock(&c->buds_lock);
+}
+
+/**
+ * ubifs_create_buds_lists - create journal head buds lists for remount rw.
+ * @c: UBIFS file-system description object
+ */
+void ubifs_create_buds_lists(struct ubifs_info *c)
+{
+	struct rb_node *p;
+
+	spin_lock(&c->buds_lock);
+	p = rb_first(&c->buds);
+	while (p) {
+		struct ubifs_bud *bud = rb_entry(p, struct ubifs_bud, rb);
+		struct ubifs_jhead *jhead = &c->jheads[bud->jhead];
+
+		list_add_tail(&bud->list, &jhead->buds_list);
+		p = rb_next(p);
+	}
+	spin_unlock(&c->buds_lock);
+}
+
+/**
+ * ubifs_add_bud_to_log - add a new bud to the log.
+ * @c: UBIFS file-system description object
+ * @jhead: journal head the bud belongs to
+ * @lnum: LEB number of the bud
+ * @offs: starting offset of the bud
+ *
+ * This function writes reference node for the new bud LEB @lnum it to the log,
+ * and adds it to the buds tress. It also makes sure that log size does not
+ * exceed the 'c->max_bud_bytes' limit. Returns zero in case of success,
+ * %-EAGAIN if commit is required, and a negative error codes in case of
+ * failure.
+ */
+int ubifs_add_bud_to_log(struct ubifs_info *c, int jhead, int lnum, int offs)
+{
+	int err;
+	struct ubifs_bud *bud;
+	struct ubifs_ref_node *ref;
+
+	bud = kmalloc(sizeof(struct ubifs_bud), GFP_NOFS);
+	if (!bud)
+		return -ENOMEM;
+	ref = kzalloc(c->ref_node_alsz, GFP_NOFS);
+	if (!ref) {
+		kfree(bud);
+		return -ENOMEM;
+	}
+
+	mutex_lock(&c->log_mutex);
+
+	if (c->ro_media) {
+		err = -EROFS;
+		goto out_unlock;
+	}
+
+	/* Make sure we have enough space in the log */
+	if (empty_log_bytes(c) - c->ref_node_alsz < c->min_log_bytes) {
+		dbg_log("not enough log space - %lld, required %d",
+			empty_log_bytes(c), c->min_log_bytes);
+		ubifs_commit_required(c);
+		err = -EAGAIN;
+		goto out_unlock;
+	}
+
+	/*
+	 * Make sure the the amount of space in buds will not exceed
+	 * 'c->max_bud_bytes' limit, because we want to guarantee mount time
+	 * limits.
+	 *
+	 * It is not necessary to hold @c->buds_lock when reading @c->bud_bytes
+	 * because we are holding @c->log_mutex. All @c->bud_bytes take place
+	 * when both @c->log_mutex and @c->bud_bytes are locked.
+	 */
+	if (c->bud_bytes + c->leb_size - offs > c->max_bud_bytes) {
+		dbg_log("bud bytes %lld (%lld max), require commit",
+			c->bud_bytes, c->max_bud_bytes);
+		ubifs_commit_required(c);
+		err = -EAGAIN;
+		goto out_unlock;
+	}
+
+	/*
+	 * If the journal is full enough - start background commit. Note, it is
+	 * OK to read 'c->cmt_state' without spinlock because integer reads
+	 * are atomic in the kernel.
+	 */
+	if (c->bud_bytes >= c->bg_bud_bytes &&
+	    c->cmt_state == COMMIT_RESTING) {
+		dbg_log("bud bytes %lld (%lld max), initiate BG commit",
+			c->bud_bytes, c->max_bud_bytes);
+		ubifs_request_bg_commit(c);
+	}
+
+	bud->lnum = lnum;
+	bud->start = offs;
+	bud->jhead = jhead;
+
+	ref->ch.node_type = UBIFS_REF_NODE;
+	ref->lnum = cpu_to_le32(bud->lnum);
+	ref->offs = cpu_to_le32(bud->start);
+	ref->jhead = cpu_to_le32(jhead);
+
+	if (c->lhead_offs > c->leb_size - c->ref_node_alsz) {
+		c->lhead_lnum = next_log_lnum(c, c->lhead_lnum);
+		c->lhead_offs = 0;
+	}
+
+	if (c->lhead_offs == 0) {
+		/* Must ensure next log LEB has been unmapped */
+		err = ubifs_leb_unmap(c, c->lhead_lnum);
+		if (err)
+			goto out_unlock;
+	}
+
+	if (bud->start == 0) {
+		/*
+		 * Before writing the LEB reference which refers an empty LEB
+		 * to the log, we have to make sure it is mapped, because
+		 * otherwise we'd risk to refer an LEB with garbage in case of
+		 * an unclean reboot, because the target LEB might have been
+		 * unmapped, but not yet physically erased.
+		 */
+		err = ubi_leb_map(c->ubi, bud->lnum, UBI_SHORTTERM);
+		if (err)
+			goto out_unlock;
+	}
+
+	dbg_log("write ref LEB %d:%d",
+		c->lhead_lnum, c->lhead_offs);
+	err = ubifs_write_node(c, ref, UBIFS_REF_NODE_SZ, c->lhead_lnum,
+			       c->lhead_offs, UBI_SHORTTERM);
+	if (err)
+		goto out_unlock;
+
+	c->lhead_offs += c->ref_node_alsz;
+
+	ubifs_add_bud(c, bud);
+
+	mutex_unlock(&c->log_mutex);
+	kfree(ref);
+	return 0;
+
+out_unlock:
+	mutex_unlock(&c->log_mutex);
+	kfree(ref);
+	kfree(bud);
+	return err;
+}
+
+/**
+ * remove_buds - remove used buds.
+ * @c: UBIFS file-system description object
+ *
+ * This function removes use buds from the buds tree. It does not remove the
+ * buds which are pointed to by journal heads.
+ */
+static void remove_buds(struct ubifs_info *c)
+{
+	struct rb_node *p;
+
+	ubifs_assert(list_empty(&c->old_buds));
+	c->cmt_bud_bytes = 0;
+	spin_lock(&c->buds_lock);
+	p = rb_first(&c->buds);
+	while (p) {
+		struct rb_node *p1 = p;
+		struct ubifs_bud *bud;
+		struct ubifs_wbuf *wbuf;
+
+		p = rb_next(p);
+		bud = rb_entry(p1, struct ubifs_bud, rb);
+		wbuf = &c->jheads[bud->jhead].wbuf;
+
+		if (wbuf->lnum == bud->lnum) {
+			/*
+			 * Do not remove buds which are pointed to by journal
+			 * heads (non-closed buds).
+			 */
+			c->cmt_bud_bytes += wbuf->offs - bud->start;
+			dbg_log("preserve %d:%d, jhead %d, bud bytes %d, "
+				"cmt_bud_bytes %lld", bud->lnum, bud->start,
+				bud->jhead, wbuf->offs - bud->start,
+				c->cmt_bud_bytes);
+			bud->start = wbuf->offs;
+		} else {
+			c->cmt_bud_bytes += c->leb_size - bud->start;
+			dbg_log("remove %d:%d, jhead %d, bud bytes %d, "
+				"cmt_bud_bytes %lld", bud->lnum, bud->start,
+				bud->jhead, c->leb_size - bud->start,
+				c->cmt_bud_bytes);
+			rb_erase(p1, &c->buds);
+			list_del(&bud->list);
+			/*
+			 * If the commit does not finish, the recovery will need
+			 * to replay the journal, in which case the old buds
+			 * must be unchanged. Do not release them until post
+			 * commit i.e. do not allow them to be garbage
+			 * collected.
+			 */
+			list_add(&bud->list, &c->old_buds);
+		}
+	}
+	spin_unlock(&c->buds_lock);
+}
+
+/**
+ * ubifs_log_start_commit - start commit.
+ * @c: UBIFS file-system description object
+ * @ltail_lnum: return new log tail LEB number
+ *
+ * The commit operation starts with writing "commit start" node to the log and
+ * reference nodes for all journal heads which will define new journal after
+ * the commit has been finished. The commit start and reference nodes are
+ * written in one go to the nearest empty log LEB (hence, when commit is
+ * finished UBIFS may safely unmap all the previous log LEBs). This function
+ * returns zero in case of success and a negative error code in case of
+ * failure.
+ */
+int ubifs_log_start_commit(struct ubifs_info *c, int *ltail_lnum)
+{
+	void *buf;
+	struct ubifs_cs_node *cs;
+	struct ubifs_ref_node *ref;
+	int err, i, max_len, len;
+
+	err = dbg_check_bud_bytes(c);
+	if (err)
+		return err;
+
+	max_len = UBIFS_CS_NODE_SZ + c->jhead_cnt * UBIFS_REF_NODE_SZ;
+	max_len = ALIGN(max_len, c->min_io_size);
+	buf = cs = kmalloc(max_len, GFP_NOFS);
+	if (!buf)
+		return -ENOMEM;
+
+	cs->ch.node_type = UBIFS_CS_NODE;
+	cs->cmt_no = cpu_to_le64(c->cmt_no + 1);
+	ubifs_prepare_node(c, cs, UBIFS_CS_NODE_SZ, 0);
+
+	/*
+	 * Note, we do not lock 'c->log_mutex' because this is the commit start
+	 * phase and we are exclusively using the log. And we do not lock
+	 * write-buffer because nobody can write to the file-system at this
+	 * phase.
+	 */
+
+	len = UBIFS_CS_NODE_SZ;
+	for (i = 0; i < c->jhead_cnt; i++) {
+		int lnum = c->jheads[i].wbuf.lnum;
+		int offs = c->jheads[i].wbuf.offs;
+
+		if (lnum == -1 || offs == c->leb_size)
+			continue;
+
+		dbg_log("add ref to LEB %d:%d for jhead %d", lnum, offs, i);
+		ref = buf + len;
+		ref->ch.node_type = UBIFS_REF_NODE;
+		ref->lnum = cpu_to_le32(lnum);
+		ref->offs = cpu_to_le32(offs);
+		ref->jhead = cpu_to_le32(i);
+
+		ubifs_prepare_node(c, ref, UBIFS_REF_NODE_SZ, 0);
+		len += UBIFS_REF_NODE_SZ;
+	}
+
+	ubifs_pad(c, buf + len, ALIGN(len, c->min_io_size) - len);
+
+	/* Switch to the next log LEB */
+	if (c->lhead_offs) {
+		c->lhead_lnum = next_log_lnum(c, c->lhead_lnum);
+		c->lhead_offs = 0;
+	}
+
+	if (c->lhead_offs == 0) {
+		/* Must ensure next LEB has been unmapped */
+		err = ubifs_leb_unmap(c, c->lhead_lnum);
+		if (err)
+			goto out;
+	}
+
+	len = ALIGN(len, c->min_io_size);
+	dbg_log("writing commit start at LEB %d:0, len %d", c->lhead_lnum, len);
+	err = ubifs_leb_write(c, c->lhead_lnum, cs, 0, len, UBI_SHORTTERM);
+	if (err)
+		goto out;
+
+	*ltail_lnum = c->lhead_lnum;
+
+	c->lhead_offs += len;
+	if (c->lhead_offs == c->leb_size) {
+		c->lhead_lnum = next_log_lnum(c, c->lhead_lnum);
+		c->lhead_offs = 0;
+	}
+
+	remove_buds(c);
+
+	/*
+	 * We have started the commit and now users may use the rest of the log
+	 * for new writes.
+	 */
+	c->min_log_bytes = 0;
+
+out:
+	kfree(buf);
+	return err;
+}
+
+/**
+ * ubifs_log_end_commit - end commit.
+ * @c: UBIFS file-system description object
+ * @ltail_lnum: new log tail LEB number
+ *
+ * This function is called on when the commit operation was finished. It
+ * moves log tail to new position and unmaps LEBs which contain obsolete data.
+ * Returns zero in case of success and a negative error code in case of
+ * failure.
+ */
+int ubifs_log_end_commit(struct ubifs_info *c, int ltail_lnum)
+{
+	int err;
+
+	/*
+	 * At this phase we have to lock 'c->log_mutex' because UBIFS allows FS
+	 * writes during commit. Its only short "commit" start phase when
+	 * writers are blocked.
+	 */
+	mutex_lock(&c->log_mutex);
+
+	dbg_log("old tail was LEB %d:0, new tail is LEB %d:0",
+		c->ltail_lnum, ltail_lnum);
+
+	c->ltail_lnum = ltail_lnum;
+	/*
+	 * The commit is finished and from now on it must be guaranteed that
+	 * there is always enough space for the next commit.
+	 */
+	c->min_log_bytes = c->leb_size;
+
+	spin_lock(&c->buds_lock);
+	c->bud_bytes -= c->cmt_bud_bytes;
+	spin_unlock(&c->buds_lock);
+
+	err = dbg_check_bud_bytes(c);
+
+	mutex_unlock(&c->log_mutex);
+	return err;
+}
+
+/**
+ * ubifs_log_post_commit - things to do after commit is completed.
+ * @c: UBIFS file-system description object
+ * @old_ltail_lnum: old log tail LEB number
+ *
+ * Release buds only after commit is completed, because they must be unchanged
+ * if recovery is needed.
+ *
+ * Unmap log LEBs only after commit is completed, because they may be needed for
+ * recovery.
+ *
+ * This function returns %0 on success and a negative error code on failure.
+ */
+int ubifs_log_post_commit(struct ubifs_info *c, int old_ltail_lnum)
+{
+	int lnum, err = 0;
+
+	while (!list_empty(&c->old_buds)) {
+		struct ubifs_bud *bud;
+
+		bud = list_entry(c->old_buds.next, struct ubifs_bud, list);
+		err = ubifs_return_leb(c, bud->lnum);
+		if (err)
+			return err;
+		list_del(&bud->list);
+		kfree(bud);
+	}
+	mutex_lock(&c->log_mutex);
+	for (lnum = old_ltail_lnum; lnum != c->ltail_lnum;
+	     lnum = next_log_lnum(c, lnum)) {
+		dbg_log("unmap log LEB %d", lnum);
+		err = ubifs_leb_unmap(c, lnum);
+		if (err)
+			goto out;
+	}
+out:
+	mutex_unlock(&c->log_mutex);
+	return err;
+}
+
+/**
+ * struct done_ref - references that have been done.
+ * @rb: rb-tree node
+ * @lnum: LEB number
+ */
+struct done_ref {
+	struct rb_node rb;
+	int lnum;
+};
+
+/**
+ * done_already - determine if a reference has been done already.
+ * @done_tree: rb-tree to store references that have been done
+ * @lnum: LEB number of reference
+ *
+ * This function returns %1 if the reference has been done, %0 if not, otherwise
+ * a negative error code is returned.
+ */
+static int done_already(struct rb_root *done_tree, int lnum)
+{
+	struct rb_node **p = &done_tree->rb_node, *parent = NULL;
+	struct done_ref *dr;
+
+	while (*p) {
+		parent = *p;
+		dr = rb_entry(parent, struct done_ref, rb);
+		if (lnum < dr->lnum)
+			p = &(*p)->rb_left;
+		else if (lnum > dr->lnum)
+			p = &(*p)->rb_right;
+		else
+			return 1;
+	}
+
+	dr = kzalloc(sizeof(struct done_ref), GFP_NOFS);
+	if (!dr)
+		return -ENOMEM;
+
+	dr->lnum = lnum;
+
+	rb_link_node(&dr->rb, parent, p);
+	rb_insert_color(&dr->rb, done_tree);
+
+	return 0;
+}
+
+/**
+ * destroy_done_tree - destroy the done tree.
+ * @done_tree: done tree to destroy
+ */
+static void destroy_done_tree(struct rb_root *done_tree)
+{
+	struct rb_node *this = done_tree->rb_node;
+	struct done_ref *dr;
+
+	while (this) {
+		if (this->rb_left) {
+			this = this->rb_left;
+			continue;
+		} else if (this->rb_right) {
+			this = this->rb_right;
+			continue;
+		}
+		dr = rb_entry(this, struct done_ref, rb);
+		this = rb_parent(this);
+		if (this) {
+			if (this->rb_left == &dr->rb)
+				this->rb_left = NULL;
+			else
+				this->rb_right = NULL;
+		}
+		kfree(dr);
+	}
+}
+
+/**
+ * add_node - add a node to the consolidated log.
+ * @c: UBIFS file-system description object
+ * @buf: buffer to which to add
+ * @lnum: LEB number to which to write is passed and returned here
+ * @offs: offset to where to write is passed and returned here
+ * @node: node to add
+ *
+ * This function returns %0 on success and a negative error code on failure.
+ */
+static int add_node(struct ubifs_info *c, void *buf, int *lnum, int *offs,
+		    void *node)
+{
+	struct ubifs_ch *ch = node;
+	int len = le32_to_cpu(ch->len), remains = c->leb_size - *offs;
+
+	if (len > remains) {
+		int sz = ALIGN(*offs, c->min_io_size), err;
+
+		ubifs_pad(c, buf + *offs, sz - *offs);
+		err = ubifs_leb_change(c, *lnum, buf, sz, UBI_SHORTTERM);
+		if (err)
+			return err;
+		*lnum = next_log_lnum(c, *lnum);
+		*offs = 0;
+	}
+	memcpy(buf + *offs, node, len);
+	*offs += ALIGN(len, 8);
+	return 0;
+}
+
+/**
+ * ubifs_consolidate_log - consolidate the log.
+ * @c: UBIFS file-system description object
+ *
+ * Repeated failed commits could cause the log to be full, but at least 1 LEB is
+ * needed for commit. This function rewrites the reference nodes in the log
+ * omitting duplicates, and failed CS nodes, and leaving no gaps.
+ *
+ * This function returns %0 on success and a negative error code on failure.
+ */
+int ubifs_consolidate_log(struct ubifs_info *c)
+{
+	struct ubifs_scan_leb *sleb;
+	struct ubifs_scan_node *snod;
+	struct rb_root done_tree = RB_ROOT;
+	int lnum, err, first = 1, write_lnum, offs = 0;
+	void *buf;
+
+	dbg_rcvry("log tail LEB %d, log head LEB %d", c->ltail_lnum,
+		  c->lhead_lnum);
+	buf = vmalloc(c->leb_size);
+	if (!buf)
+		return -ENOMEM;
+	lnum = c->ltail_lnum;
+	write_lnum = lnum;
+	while (1) {
+		sleb = ubifs_scan(c, lnum, 0, c->sbuf);
+		if (IS_ERR(sleb)) {
+			err = PTR_ERR(sleb);
+			goto out_free;
+		}
+		list_for_each_entry(snod, &sleb->nodes, list) {
+			switch (snod->type) {
+			case UBIFS_REF_NODE: {
+				struct ubifs_ref_node *ref = snod->node;
+				int ref_lnum = le32_to_cpu(ref->lnum);
+
+				err = done_already(&done_tree, ref_lnum);
+				if (err < 0)
+					goto out_scan;
+				if (err != 1) {
+					err = add_node(c, buf, &write_lnum,
+						       &offs, snod->node);
+					if (err)
+						goto out_scan;
+				}
+				break;
+			}
+			case UBIFS_CS_NODE:
+				if (!first)
+					break;
+				err = add_node(c, buf, &write_lnum, &offs,
+					       snod->node);
+				if (err)
+					goto out_scan;
+				first = 0;
+				break;
+			}
+		}
+		ubifs_scan_destroy(sleb);
+		if (lnum == c->lhead_lnum)
+			break;
+		lnum = next_log_lnum(c, lnum);
+	}
+	if (offs) {
+		int sz = ALIGN(offs, c->min_io_size);
+
+		ubifs_pad(c, buf + offs, sz - offs);
+		err = ubifs_leb_change(c, write_lnum, buf, sz, UBI_SHORTTERM);
+		if (err)
+			goto out_free;
+		offs = ALIGN(offs, c->min_io_size);
+	}
+	destroy_done_tree(&done_tree);
+	vfree(buf);
+	if (write_lnum == c->lhead_lnum) {
+		ubifs_err("log is too full");
+		return -EINVAL;
+	}
+	/* Unmap remaining LEBs */
+	lnum = write_lnum;
+	do {
+		lnum = next_log_lnum(c, lnum);
+		err = ubifs_leb_unmap(c, lnum);
+		if (err)
+			return err;
+	} while (lnum != c->lhead_lnum);
+	c->lhead_lnum = write_lnum;
+	c->lhead_offs = offs;
+	dbg_rcvry("new log head at %d:%d", c->lhead_lnum, c->lhead_offs);
+	return 0;
+
+out_scan:
+	ubifs_scan_destroy(sleb);
+out_free:
+	destroy_done_tree(&done_tree);
+	vfree(buf);
+	return err;
+}
+
+#ifdef CONFIG_UBIFS_FS_DEBUG
+
+/**
+ * dbg_check_bud_bytes - make sure bud bytes calculation are all right.
+ * @c: UBIFS file-system description object
+ *
+ * This function makes sure the amount of flash space used by closed buds
+ * ('c->bud_bytes' is correct). Returns zero in case of success and %-EINVAL in
+ * case of failure.
+ */
+static int dbg_check_bud_bytes(struct ubifs_info *c)
+{
+	int i, err = 0;
+	struct ubifs_bud *bud;
+	long long bud_bytes = 0;
+
+	if (!(ubifs_chk_flags & UBIFS_CHK_GEN))
+		return 0;
+
+	spin_lock(&c->buds_lock);
+	for (i = 0; i < c->jhead_cnt; i++)
+		list_for_each_entry(bud, &c->jheads[i].buds_list, list)
+			bud_bytes += c->leb_size - bud->start;
+
+	if (c->bud_bytes != bud_bytes) {
+		ubifs_err("bad bud_bytes %lld, calculated %lld",
+			  c->bud_bytes, bud_bytes);
+		err = -EINVAL;
+	}
+	spin_unlock(&c->buds_lock);
+
+	return err;
+}
+
+#endif /* CONFIG_UBIFS_FS_DEBUG */
diff --git a/fs/ubifs/lprops.c b/fs/ubifs/lprops.c
new file mode 100644
index 00000000000..2ba93da71b6
--- /dev/null
+++ b/fs/ubifs/lprops.c
@@ -0,0 +1,1357 @@
+/*
+ * This file is part of UBIFS.
+ *
+ * Copyright (C) 2006-2008 Nokia Corporation.
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 as published by
+ * the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
+ * more details.
+ *
+ * You should have received a copy of the GNU General Public License along with
+ * this program; if not, write to the Free Software Foundation, Inc., 51
+ * Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
+ *
+ * Authors: Adrian Hunter
+ *          Artem Bityutskiy (Битюцкий Артём)
+ */
+
+/*
+ * This file implements the functions that access LEB properties and their
+ * categories. LEBs are categorized based on the needs of UBIFS, and the
+ * categories are stored as either heaps or lists to provide a fast way of
+ * finding a LEB in a particular category. For example, UBIFS may need to find
+ * an empty LEB for the journal, or a very dirty LEB for garbage collection.
+ */
+
+#include "ubifs.h"
+
+/**
+ * get_heap_comp_val - get the LEB properties value for heap comparisons.
+ * @lprops: LEB properties
+ * @cat: LEB category
+ */
+static int get_heap_comp_val(struct ubifs_lprops *lprops, int cat)
+{
+	switch (cat) {
+	case LPROPS_FREE:
+		return lprops->free;
+	case LPROPS_DIRTY_IDX:
+		return lprops->free + lprops->dirty;
+	default:
+		return lprops->dirty;
+	}
+}
+
+/**
+ * move_up_lpt_heap - move a new heap entry up as far as possible.
+ * @c: UBIFS file-system description object
+ * @heap: LEB category heap
+ * @lprops: LEB properties to move
+ * @cat: LEB category
+ *
+ * New entries to a heap are added at the bottom and then moved up until the
+ * parent's value is greater.  In the case of LPT's category heaps, the value
+ * is either the amount of free space or the amount of dirty space, depending
+ * on the category.
+ */
+static void move_up_lpt_heap(struct ubifs_info *c, struct ubifs_lpt_heap *heap,
+			     struct ubifs_lprops *lprops, int cat)
+{
+	int val1, val2, hpos;
+
+	hpos = lprops->hpos;
+	if (!hpos)
+		return; /* Already top of the heap */
+	val1 = get_heap_comp_val(lprops, cat);
+	/* Compare to parent and, if greater, move up the heap */
+	do {
+		int ppos = (hpos - 1) / 2;
+
+		val2 = get_heap_comp_val(heap->arr[ppos], cat);
+		if (val2 >= val1)
+			return;
+		/* Greater than parent so move up */
+		heap->arr[ppos]->hpos = hpos;
+		heap->arr[hpos] = heap->arr[ppos];
+		heap->arr[ppos] = lprops;
+		lprops->hpos = ppos;
+		hpos = ppos;
+	} while (hpos);
+}
+
+/**
+ * adjust_lpt_heap - move a changed heap entry up or down the heap.
+ * @c: UBIFS file-system description object
+ * @heap: LEB category heap
+ * @lprops: LEB properties to move
+ * @hpos: heap position of @lprops
+ * @cat: LEB category
+ *
+ * Changed entries in a heap are moved up or down until the parent's value is
+ * greater.  In the case of LPT's category heaps, the value is either the amount
+ * of free space or the amount of dirty space, depending on the category.
+ */
+static void adjust_lpt_heap(struct ubifs_info *c, struct ubifs_lpt_heap *heap,
+			    struct ubifs_lprops *lprops, int hpos, int cat)
+{
+	int val1, val2, val3, cpos;
+
+	val1 = get_heap_comp_val(lprops, cat);
+	/* Compare to parent and, if greater than parent, move up the heap */
+	if (hpos) {
+		int ppos = (hpos - 1) / 2;
+
+		val2 = get_heap_comp_val(heap->arr[ppos], cat);
+		if (val1 > val2) {
+			/* Greater than parent so move up */
+			while (1) {
+				heap->arr[ppos]->hpos = hpos;
+				heap->arr[hpos] = heap->arr[ppos];
+				heap->arr[ppos] = lprops;
+				lprops->hpos = ppos;
+				hpos = ppos;
+				if (!hpos)
+					return;
+				ppos = (hpos - 1) / 2;
+				val2 = get_heap_comp_val(heap->arr[ppos], cat);
+				if (val1 <= val2)
+					return;
+				/* Still greater than parent so keep going */
+			}
+		}
+	}
+	/* Not greater than parent, so compare to children */
+	while (1) {
+		/* Compare to left child */
+		cpos = hpos * 2 + 1;
+		if (cpos >= heap->cnt)
+			return;
+		val2 = get_heap_comp_val(heap->arr[cpos], cat);
+		if (val1 < val2) {
+			/* Less than left child, so promote biggest child */
+			if (cpos + 1 < heap->cnt) {
+				val3 = get_heap_comp_val(heap->arr[cpos + 1],
+							 cat);
+				if (val3 > val2)
+					cpos += 1; /* Right child is bigger */
+			}
+			heap->arr[cpos]->hpos = hpos;
+			heap->arr[hpos] = heap->arr[cpos];
+			heap->arr[cpos] = lprops;
+			lprops->hpos = cpos;
+			hpos = cpos;
+			continue;
+		}
+		/* Compare to right child */
+		cpos += 1;
+		if (cpos >= heap->cnt)
+			return;
+		val3 = get_heap_comp_val(heap->arr[cpos], cat);
+		if (val1 < val3) {
+			/* Less than right child, so promote right child */
+			heap->arr[cpos]->hpos = hpos;
+			heap->arr[hpos] = heap->arr[cpos];
+			heap->arr[cpos] = lprops;
+			lprops->hpos = cpos;
+			hpos = cpos;
+			continue;
+		}
+		return;
+	}
+}
+
+/**
+ * add_to_lpt_heap - add LEB properties to a LEB category heap.
+ * @c: UBIFS file-system description object
+ * @lprops: LEB properties to add
+ * @cat: LEB category
+ *
+ * This function returns %1 if @lprops is added to the heap for LEB category
+ * @cat, otherwise %0 is returned because the heap is full.
+ */
+static int add_to_lpt_heap(struct ubifs_info *c, struct ubifs_lprops *lprops,
+			   int cat)
+{
+	struct ubifs_lpt_heap *heap = &c->lpt_heap[cat - 1];
+
+	if (heap->cnt >= heap->max_cnt) {
+		const int b = LPT_HEAP_SZ / 2 - 1;
+		int cpos, val1, val2;
+
+		/* Compare to some other LEB on the bottom of heap */
+		/* Pick a position kind of randomly */
+		cpos = (((size_t)lprops >> 4) & b) + b;
+		ubifs_assert(cpos >= b);
+		ubifs_assert(cpos < LPT_HEAP_SZ);
+		ubifs_assert(cpos < heap->cnt);
+
+		val1 = get_heap_comp_val(lprops, cat);
+		val2 = get_heap_comp_val(heap->arr[cpos], cat);
+		if (val1 > val2) {
+			struct ubifs_lprops *lp;
+
+			lp = heap->arr[cpos];
+			lp->flags &= ~LPROPS_CAT_MASK;
+			lp->flags |= LPROPS_UNCAT;
+			list_add(&lp->list, &c->uncat_list);
+			lprops->hpos = cpos;
+			heap->arr[cpos] = lprops;
+			move_up_lpt_heap(c, heap, lprops, cat);
+			dbg_check_heap(c, heap, cat, lprops->hpos);
+			return 1; /* Added to heap */
+		}
+		dbg_check_heap(c, heap, cat, -1);
+		return 0; /* Not added to heap */
+	} else {
+		lprops->hpos = heap->cnt++;
+		heap->arr[lprops->hpos] = lprops;
+		move_up_lpt_heap(c, heap, lprops, cat);
+		dbg_check_heap(c, heap, cat, lprops->hpos);
+		return 1; /* Added to heap */
+	}
+}
+
+/**
+ * remove_from_lpt_heap - remove LEB properties from a LEB category heap.
+ * @c: UBIFS file-system description object
+ * @lprops: LEB properties to remove
+ * @cat: LEB category
+ */
+static void remove_from_lpt_heap(struct ubifs_info *c,
+				 struct ubifs_lprops *lprops, int cat)
+{
+	struct ubifs_lpt_heap *heap;
+	int hpos = lprops->hpos;
+
+	heap = &c->lpt_heap[cat - 1];
+	ubifs_assert(hpos >= 0 && hpos < heap->cnt);
+	ubifs_assert(heap->arr[hpos] == lprops);
+	heap->cnt -= 1;
+	if (hpos < heap->cnt) {
+		heap->arr[hpos] = heap->arr[heap->cnt];
+		heap->arr[hpos]->hpos = hpos;
+		adjust_lpt_heap(c, heap, heap->arr[hpos], hpos, cat);
+	}
+	dbg_check_heap(c, heap, cat, -1);
+}
+
+/**
+ * lpt_heap_replace - replace lprops in a category heap.
+ * @c: UBIFS file-system description object
+ * @old_lprops: LEB properties to replace
+ * @new_lprops: LEB properties with which to replace
+ * @cat: LEB category
+ *
+ * During commit it is sometimes necessary to copy a pnode (see dirty_cow_pnode)
+ * and the lprops that the pnode contains.  When that happens, references in
+ * the category heaps to those lprops must be updated to point to the new
+ * lprops.  This function does that.
+ */
+static void lpt_heap_replace(struct ubifs_info *c,
+			     struct ubifs_lprops *old_lprops,
+			     struct ubifs_lprops *new_lprops, int cat)
+{
+	struct ubifs_lpt_heap *heap;
+	int hpos = new_lprops->hpos;
+
+	heap = &c->lpt_heap[cat - 1];
+	heap->arr[hpos] = new_lprops;
+}
+
+/**
+ * ubifs_add_to_cat - add LEB properties to a category list or heap.
+ * @c: UBIFS file-system description object
+ * @lprops: LEB properties to add
+ * @cat: LEB category to which to add
+ *
+ * LEB properties are categorized to enable fast find operations.
+ */
+void ubifs_add_to_cat(struct ubifs_info *c, struct ubifs_lprops *lprops,
+		      int cat)
+{
+	switch (cat) {
+	case LPROPS_DIRTY:
+	case LPROPS_DIRTY_IDX:
+	case LPROPS_FREE:
+		if (add_to_lpt_heap(c, lprops, cat))
+			break;
+		/* No more room on heap so make it uncategorized */
+		cat = LPROPS_UNCAT;
+		/* Fall through */
+	case LPROPS_UNCAT:
+		list_add(&lprops->list, &c->uncat_list);
+		break;
+	case LPROPS_EMPTY:
+		list_add(&lprops->list, &c->empty_list);
+		break;
+	case LPROPS_FREEABLE:
+		list_add(&lprops->list, &c->freeable_list);
+		c->freeable_cnt += 1;
+		break;
+	case LPROPS_FRDI_IDX:
+		list_add(&lprops->list, &c->frdi_idx_list);
+		break;
+	default:
+		ubifs_assert(0);
+	}
+	lprops->flags &= ~LPROPS_CAT_MASK;
+	lprops->flags |= cat;
+}
+
+/**
+ * ubifs_remove_from_cat - remove LEB properties from a category list or heap.
+ * @c: UBIFS file-system description object
+ * @lprops: LEB properties to remove
+ * @cat: LEB category from which to remove
+ *
+ * LEB properties are categorized to enable fast find operations.
+ */
+static void ubifs_remove_from_cat(struct ubifs_info *c,
+				  struct ubifs_lprops *lprops, int cat)
+{
+	switch (cat) {
+	case LPROPS_DIRTY:
+	case LPROPS_DIRTY_IDX:
+	case LPROPS_FREE:
+		remove_from_lpt_heap(c, lprops, cat);
+		break;
+	case LPROPS_FREEABLE:
+		c->freeable_cnt -= 1;
+		ubifs_assert(c->freeable_cnt >= 0);
+		/* Fall through */
+	case LPROPS_UNCAT:
+	case LPROPS_EMPTY:
+	case LPROPS_FRDI_IDX:
+		ubifs_assert(!list_empty(&lprops->list));
+		list_del(&lprops->list);
+		break;
+	default:
+		ubifs_assert(0);
+	}
+}
+
+/**
+ * ubifs_replace_cat - replace lprops in a category list or heap.
+ * @c: UBIFS file-system description object
+ * @old_lprops: LEB properties to replace
+ * @new_lprops: LEB properties with which to replace
+ *
+ * During commit it is sometimes necessary to copy a pnode (see dirty_cow_pnode)
+ * and the lprops that the pnode contains. When that happens, references in
+ * category lists and heaps must be replaced. This function does that.
+ */
+void ubifs_replace_cat(struct ubifs_info *c, struct ubifs_lprops *old_lprops,
+		       struct ubifs_lprops *new_lprops)
+{
+	int cat;
+
+	cat = new_lprops->flags & LPROPS_CAT_MASK;
+	switch (cat) {
+	case LPROPS_DIRTY:
+	case LPROPS_DIRTY_IDX:
+	case LPROPS_FREE:
+		lpt_heap_replace(c, old_lprops, new_lprops, cat);
+		break;
+	case LPROPS_UNCAT:
+	case LPROPS_EMPTY:
+	case LPROPS_FREEABLE:
+	case LPROPS_FRDI_IDX:
+		list_replace(&old_lprops->list, &new_lprops->list);
+		break;
+	default:
+		ubifs_assert(0);
+	}
+}
+
+/**
+ * ubifs_ensure_cat - ensure LEB properties are categorized.
+ * @c: UBIFS file-system description object
+ * @lprops: LEB properties
+ *
+ * A LEB may have fallen off of the bottom of a heap, and ended up as
+ * uncategorized even though it has enough space for us now. If that is the case
+ * this function will put the LEB back onto a heap.
+ */
+void ubifs_ensure_cat(struct ubifs_info *c, struct ubifs_lprops *lprops)
+{
+	int cat = lprops->flags & LPROPS_CAT_MASK;
+
+	if (cat != LPROPS_UNCAT)
+		return;
+	cat = ubifs_categorize_lprops(c, lprops);
+	if (cat == LPROPS_UNCAT)
+		return;
+	ubifs_remove_from_cat(c, lprops, LPROPS_UNCAT);
+	ubifs_add_to_cat(c, lprops, cat);
+}
+
+/**
+ * ubifs_categorize_lprops - categorize LEB properties.
+ * @c: UBIFS file-system description object
+ * @lprops: LEB properties to categorize
+ *
+ * LEB properties are categorized to enable fast find operations. This function
+ * returns the LEB category to which the LEB properties belong. Note however
+ * that if the LEB category is stored as a heap and the heap is full, the
+ * LEB properties may have their category changed to %LPROPS_UNCAT.
+ */
+int ubifs_categorize_lprops(const struct ubifs_info *c,
+			    const struct ubifs_lprops *lprops)
+{
+	if (lprops->flags & LPROPS_TAKEN)
+		return LPROPS_UNCAT;
+
+	if (lprops->free == c->leb_size) {
+		ubifs_assert(!(lprops->flags & LPROPS_INDEX));
+		return LPROPS_EMPTY;
+	}
+
+	if (lprops->free + lprops->dirty == c->leb_size) {
+		if (lprops->flags & LPROPS_INDEX)
+			return LPROPS_FRDI_IDX;
+		else
+			return LPROPS_FREEABLE;
+	}
+
+	if (lprops->flags & LPROPS_INDEX) {
+		if (lprops->dirty + lprops->free >= c->min_idx_node_sz)
+			return LPROPS_DIRTY_IDX;
+	} else {
+		if (lprops->dirty >= c->dead_wm &&
+		    lprops->dirty > lprops->free)
+			return LPROPS_DIRTY;
+		if (lprops->free > 0)
+			return LPROPS_FREE;
+	}
+
+	return LPROPS_UNCAT;
+}
+
+/**
+ * change_category - change LEB properties category.
+ * @c: UBIFS file-system description object
+ * @lprops: LEB properties to recategorize
+ *
+ * LEB properties are categorized to enable fast find operations. When the LEB
+ * properties change they must be recategorized.
+ */
+static void change_category(struct ubifs_info *c, struct ubifs_lprops *lprops)
+{
+	int old_cat = lprops->flags & LPROPS_CAT_MASK;
+	int new_cat = ubifs_categorize_lprops(c, lprops);
+
+	if (old_cat == new_cat) {
+		struct ubifs_lpt_heap *heap = &c->lpt_heap[new_cat - 1];
+
+		/* lprops on a heap now must be moved up or down */
+		if (new_cat < 1 || new_cat > LPROPS_HEAP_CNT)
+			return; /* Not on a heap */
+		heap = &c->lpt_heap[new_cat - 1];
+		adjust_lpt_heap(c, heap, lprops, lprops->hpos, new_cat);
+	} else {
+		ubifs_remove_from_cat(c, lprops, old_cat);
+		ubifs_add_to_cat(c, lprops, new_cat);
+	}
+}
+
+/**
+ * ubifs_get_lprops - get reference to LEB properties.
+ * @c: the UBIFS file-system description object
+ *
+ * This function locks lprops. Lprops have to be unlocked by
+ * 'ubifs_release_lprops()'.
+ */
+void ubifs_get_lprops(struct ubifs_info *c)
+{
+	mutex_lock(&c->lp_mutex);
+}
+
+/**
+ * calc_dark - calculate LEB dark space size.
+ * @c: the UBIFS file-system description object
+ * @spc: amount of free and dirty space in the LEB
+ *
+ * This function calculates amount of dark space in an LEB which has @spc bytes
+ * of free and dirty space. Returns the calculations result.
+ *
+ * Dark space is the space which is not always usable - it depends on which
+ * nodes are written in which order. E.g., if an LEB has only 512 free bytes,
+ * it is dark space, because it cannot fit a large data node. So UBIFS cannot
+ * count on this LEB and treat these 512 bytes as usable because it is not true
+ * if, for example, only big chunks of uncompressible data will be written to
+ * the FS.
+ */
+static int calc_dark(struct ubifs_info *c, int spc)
+{
+	ubifs_assert(!(spc & 7));
+
+	if (spc < c->dark_wm)
+		return spc;
+
+	/*
+	 * If we have slightly more space then the dark space watermark, we can
+	 * anyway safely assume it we'll be able to write a node of the
+	 * smallest size there.
+	 */
+	if (spc - c->dark_wm < MIN_WRITE_SZ)
+		return spc - MIN_WRITE_SZ;
+
+	return c->dark_wm;
+}
+
+/**
+ * is_lprops_dirty - determine if LEB properties are dirty.
+ * @c: the UBIFS file-system description object
+ * @lprops: LEB properties to test
+ */
+static int is_lprops_dirty(struct ubifs_info *c, struct ubifs_lprops *lprops)
+{
+	struct ubifs_pnode *pnode;
+	int pos;
+
+	pos = (lprops->lnum - c->main_first) & (UBIFS_LPT_FANOUT - 1);
+	pnode = (struct ubifs_pnode *)container_of(lprops - pos,
+						   struct ubifs_pnode,
+						   lprops[0]);
+	return !test_bit(COW_ZNODE, &pnode->flags) &&
+	       test_bit(DIRTY_CNODE, &pnode->flags);
+}
+
+/**
+ * ubifs_change_lp - change LEB properties.
+ * @c: the UBIFS file-system description object
+ * @lp: LEB properties to change
+ * @free: new free space amount
+ * @dirty: new dirty space amount
+ * @flags: new flags
+ * @idx_gc_cnt: change to the count of idx_gc list
+ *
+ * This function changes LEB properties. This function does not change a LEB
+ * property (@free, @dirty or @flag) if the value passed is %LPROPS_NC.
+ *
+ * This function returns a pointer to the updated LEB properties on success
+ * and a negative error code on failure. N.B. the LEB properties may have had to
+ * be copied (due to COW) and consequently the pointer returned may not be the
+ * same as the pointer passed.
+ */
+const struct ubifs_lprops *ubifs_change_lp(struct ubifs_info *c,
+					   const struct ubifs_lprops *lp,
+					   int free, int dirty, int flags,
+					   int idx_gc_cnt)
+{
+	/*
+	 * This is the only function that is allowed to change lprops, so we
+	 * discard the const qualifier.
+	 */
+	struct ubifs_lprops *lprops = (struct ubifs_lprops *)lp;
+
+	dbg_lp("LEB %d, free %d, dirty %d, flags %d",
+	       lprops->lnum, free, dirty, flags);
+
+	ubifs_assert(mutex_is_locked(&c->lp_mutex));
+	ubifs_assert(c->lst.empty_lebs >= 0 &&
+		     c->lst.empty_lebs <= c->main_lebs);
+	ubifs_assert(c->freeable_cnt >= 0);
+	ubifs_assert(c->freeable_cnt <= c->main_lebs);
+	ubifs_assert(c->lst.taken_empty_lebs >= 0);
+	ubifs_assert(c->lst.taken_empty_lebs <= c->lst.empty_lebs);
+	ubifs_assert(!(c->lst.total_free & 7) && !(c->lst.total_dirty & 7));
+	ubifs_assert(!(c->lst.total_dead & 7) && !(c->lst.total_dark & 7));
+	ubifs_assert(!(c->lst.total_used & 7));
+	ubifs_assert(free == LPROPS_NC || free >= 0);
+	ubifs_assert(dirty == LPROPS_NC || dirty >= 0);
+
+	if (!is_lprops_dirty(c, lprops)) {
+		lprops = ubifs_lpt_lookup_dirty(c, lprops->lnum);
+		if (IS_ERR(lprops))
+			return lprops;
+	} else
+		ubifs_assert(lprops == ubifs_lpt_lookup_dirty(c, lprops->lnum));
+
+	ubifs_assert(!(lprops->free & 7) && !(lprops->dirty & 7));
+
+	spin_lock(&c->space_lock);
+
+	if ((lprops->flags & LPROPS_TAKEN) && lprops->free == c->leb_size)
+		c->lst.taken_empty_lebs -= 1;
+
+	if (!(lprops->flags & LPROPS_INDEX)) {
+		int old_spc;
+
+		old_spc = lprops->free + lprops->dirty;
+		if (old_spc < c->dead_wm)
+			c->lst.total_dead -= old_spc;
+		else
+			c->lst.total_dark -= calc_dark(c, old_spc);
+
+		c->lst.total_used -= c->leb_size - old_spc;
+	}
+
+	if (free != LPROPS_NC) {
+		free = ALIGN(free, 8);
+		c->lst.total_free += free - lprops->free;
+
+		/* Increase or decrease empty LEBs counter if needed */
+		if (free == c->leb_size) {
+			if (lprops->free != c->leb_size)
+				c->lst.empty_lebs += 1;
+		} else if (lprops->free == c->leb_size)
+			c->lst.empty_lebs -= 1;
+		lprops->free = free;
+	}
+
+	if (dirty != LPROPS_NC) {
+		dirty = ALIGN(dirty, 8);
+		c->lst.total_dirty += dirty - lprops->dirty;
+		lprops->dirty = dirty;
+	}
+
+	if (flags != LPROPS_NC) {
+		/* Take care about indexing LEBs counter if needed */
+		if ((lprops->flags & LPROPS_INDEX)) {
+			if (!(flags & LPROPS_INDEX))
+				c->lst.idx_lebs -= 1;
+		} else if (flags & LPROPS_INDEX)
+			c->lst.idx_lebs += 1;
+		lprops->flags = flags;
+	}
+
+	if (!(lprops->flags & LPROPS_INDEX)) {
+		int new_spc;
+
+		new_spc = lprops->free + lprops->dirty;
+		if (new_spc < c->dead_wm)
+			c->lst.total_dead += new_spc;
+		else
+			c->lst.total_dark += calc_dark(c, new_spc);
+
+		c->lst.total_used += c->leb_size - new_spc;
+	}
+
+	if ((lprops->flags & LPROPS_TAKEN) && lprops->free == c->leb_size)
+		c->lst.taken_empty_lebs += 1;
+
+	change_category(c, lprops);
+
+	c->idx_gc_cnt += idx_gc_cnt;
+
+	spin_unlock(&c->space_lock);
+
+	return lprops;
+}
+
+/**
+ * ubifs_release_lprops - release lprops lock.
+ * @c: the UBIFS file-system description object
+ *
+ * This function has to be called after each 'ubifs_get_lprops()' call to
+ * unlock lprops.
+ */
+void ubifs_release_lprops(struct ubifs_info *c)
+{
+	ubifs_assert(mutex_is_locked(&c->lp_mutex));
+	ubifs_assert(c->lst.empty_lebs >= 0 &&
+		     c->lst.empty_lebs <= c->main_lebs);
+
+	mutex_unlock(&c->lp_mutex);
+}
+
+/**
+ * ubifs_get_lp_stats - get lprops statistics.
+ * @c: UBIFS file-system description object
+ * @st: return statistics
+ */
+void ubifs_get_lp_stats(struct ubifs_info *c, struct ubifs_lp_stats *st)
+{
+	spin_lock(&c->space_lock);
+	memcpy(st, &c->lst, sizeof(struct ubifs_lp_stats));
+	spin_unlock(&c->space_lock);
+}
+
+/**
+ * ubifs_change_one_lp - change LEB properties.
+ * @c: the UBIFS file-system description object
+ * @lnum: LEB to change properties for
+ * @free: amount of free space
+ * @dirty: amount of dirty space
+ * @flags_set: flags to set
+ * @flags_clean: flags to clean
+ * @idx_gc_cnt: change to the count of idx_gc list
+ *
+ * This function changes properties of LEB @lnum. It is a helper wrapper over
+ * 'ubifs_change_lp()' which hides lprops get/release. The arguments are the
+ * same as in case of 'ubifs_change_lp()'. Returns zero in case of success and
+ * a negative error code in case of failure.
+ */
+int ubifs_change_one_lp(struct ubifs_info *c, int lnum, int free, int dirty,
+			int flags_set, int flags_clean, int idx_gc_cnt)
+{
+	int err = 0, flags;
+	const struct ubifs_lprops *lp;
+
+	ubifs_get_lprops(c);
+
+	lp = ubifs_lpt_lookup_dirty(c, lnum);
+	if (IS_ERR(lp)) {
+		err = PTR_ERR(lp);
+		goto out;
+	}
+
+	flags = (lp->flags | flags_set) & ~flags_clean;
+	lp = ubifs_change_lp(c, lp, free, dirty, flags, idx_gc_cnt);
+	if (IS_ERR(lp))
+		err = PTR_ERR(lp);
+
+out:
+	ubifs_release_lprops(c);
+	return err;
+}
+
+/**
+ * ubifs_update_one_lp - update LEB properties.
+ * @c: the UBIFS file-system description object
+ * @lnum: LEB to change properties for
+ * @free: amount of free space
+ * @dirty: amount of dirty space to add
+ * @flags_set: flags to set
+ * @flags_clean: flags to clean
+ *
+ * This function is the same as 'ubifs_change_one_lp()' but @dirty is added to
+ * current dirty space, not substitutes it.
+ */
+int ubifs_update_one_lp(struct ubifs_info *c, int lnum, int free, int dirty,
+			int flags_set, int flags_clean)
+{
+	int err = 0, flags;
+	const struct ubifs_lprops *lp;
+
+	ubifs_get_lprops(c);
+
+	lp = ubifs_lpt_lookup_dirty(c, lnum);
+	if (IS_ERR(lp)) {
+		err = PTR_ERR(lp);
+		goto out;
+	}
+
+	flags = (lp->flags | flags_set) & ~flags_clean;
+	lp = ubifs_change_lp(c, lp, free, lp->dirty + dirty, flags, 0);
+	if (IS_ERR(lp))
+		err = PTR_ERR(lp);
+
+out:
+	ubifs_release_lprops(c);
+	return err;
+}
+
+/**
+ * ubifs_read_one_lp - read LEB properties.
+ * @c: the UBIFS file-system description object
+ * @lnum: LEB to read properties for
+ * @lp: where to store read properties
+ *
+ * This helper function reads properties of a LEB @lnum and stores them in @lp.
+ * Returns zero in case of success and a negative error code in case of
+ * failure.
+ */
+int ubifs_read_one_lp(struct ubifs_info *c, int lnum, struct ubifs_lprops *lp)
+{
+	int err = 0;
+	const struct ubifs_lprops *lpp;
+
+	ubifs_get_lprops(c);
+
+	lpp = ubifs_lpt_lookup(c, lnum);
+	if (IS_ERR(lpp)) {
+		err = PTR_ERR(lpp);
+		goto out;
+	}
+
+	memcpy(lp, lpp, sizeof(struct ubifs_lprops));
+
+out:
+	ubifs_release_lprops(c);
+	return err;
+}
+
+/**
+ * ubifs_fast_find_free - try to find a LEB with free space quickly.
+ * @c: the UBIFS file-system description object
+ *
+ * This function returns LEB properties for a LEB with free space or %NULL if
+ * the function is unable to find a LEB quickly.
+ */
+const struct ubifs_lprops *ubifs_fast_find_free(struct ubifs_info *c)
+{
+	struct ubifs_lprops *lprops;
+	struct ubifs_lpt_heap *heap;
+
+	ubifs_assert(mutex_is_locked(&c->lp_mutex));
+
+	heap = &c->lpt_heap[LPROPS_FREE - 1];
+	if (heap->cnt == 0)
+		return NULL;
+
+	lprops = heap->arr[0];
+	ubifs_assert(!(lprops->flags & LPROPS_TAKEN));
+	ubifs_assert(!(lprops->flags & LPROPS_INDEX));
+	return lprops;
+}
+
+/**
+ * ubifs_fast_find_empty - try to find an empty LEB quickly.
+ * @c: the UBIFS file-system description object
+ *
+ * This function returns LEB properties for an empty LEB or %NULL if the
+ * function is unable to find an empty LEB quickly.
+ */
+const struct ubifs_lprops *ubifs_fast_find_empty(struct ubifs_info *c)
+{
+	struct ubifs_lprops *lprops;
+
+	ubifs_assert(mutex_is_locked(&c->lp_mutex));
+
+	if (list_empty(&c->empty_list))
+		return NULL;
+
+	lprops = list_entry(c->empty_list.next, struct ubifs_lprops, list);
+	ubifs_assert(!(lprops->flags & LPROPS_TAKEN));
+	ubifs_assert(!(lprops->flags & LPROPS_INDEX));
+	ubifs_assert(lprops->free == c->leb_size);
+	return lprops;
+}
+
+/**
+ * ubifs_fast_find_freeable - try to find a freeable LEB quickly.
+ * @c: the UBIFS file-system description object
+ *
+ * This function returns LEB properties for a freeable LEB or %NULL if the
+ * function is unable to find a freeable LEB quickly.
+ */
+const struct ubifs_lprops *ubifs_fast_find_freeable(struct ubifs_info *c)
+{
+	struct ubifs_lprops *lprops;
+
+	ubifs_assert(mutex_is_locked(&c->lp_mutex));
+
+	if (list_empty(&c->freeable_list))
+		return NULL;
+
+	lprops = list_entry(c->freeable_list.next, struct ubifs_lprops, list);
+	ubifs_assert(!(lprops->flags & LPROPS_TAKEN));
+	ubifs_assert(!(lprops->flags & LPROPS_INDEX));
+	ubifs_assert(lprops->free + lprops->dirty == c->leb_size);
+	ubifs_assert(c->freeable_cnt > 0);
+	return lprops;
+}
+
+/**
+ * ubifs_fast_find_frdi_idx - try to find a freeable index LEB quickly.
+ * @c: the UBIFS file-system description object
+ *
+ * This function returns LEB properties for a freeable index LEB or %NULL if the
+ * function is unable to find a freeable index LEB quickly.
+ */
+const struct ubifs_lprops *ubifs_fast_find_frdi_idx(struct ubifs_info *c)
+{
+	struct ubifs_lprops *lprops;
+
+	ubifs_assert(mutex_is_locked(&c->lp_mutex));
+
+	if (list_empty(&c->frdi_idx_list))
+		return NULL;
+
+	lprops = list_entry(c->frdi_idx_list.next, struct ubifs_lprops, list);
+	ubifs_assert(!(lprops->flags & LPROPS_TAKEN));
+	ubifs_assert((lprops->flags & LPROPS_INDEX));
+	ubifs_assert(lprops->free + lprops->dirty == c->leb_size);
+	return lprops;
+}
+
+#ifdef CONFIG_UBIFS_FS_DEBUG
+
+/**
+ * dbg_check_cats - check category heaps and lists.
+ * @c: UBIFS file-system description object
+ *
+ * This function returns %0 on success and a negative error code on failure.
+ */
+int dbg_check_cats(struct ubifs_info *c)
+{
+	struct ubifs_lprops *lprops;
+	struct list_head *pos;
+	int i, cat;
+
+	if (!(ubifs_chk_flags & (UBIFS_CHK_GEN | UBIFS_CHK_LPROPS)))
+		return 0;
+
+	list_for_each_entry(lprops, &c->empty_list, list) {
+		if (lprops->free != c->leb_size) {
+			ubifs_err("non-empty LEB %d on empty list "
+				  "(free %d dirty %d flags %d)", lprops->lnum,
+				  lprops->free, lprops->dirty, lprops->flags);
+			return -EINVAL;
+		}
+		if (lprops->flags & LPROPS_TAKEN) {
+			ubifs_err("taken LEB %d on empty list "
+				  "(free %d dirty %d flags %d)", lprops->lnum,
+				  lprops->free, lprops->dirty, lprops->flags);
+			return -EINVAL;
+		}
+	}
+
+	i = 0;
+	list_for_each_entry(lprops, &c->freeable_list, list) {
+		if (lprops->free + lprops->dirty != c->leb_size) {
+			ubifs_err("non-freeable LEB %d on freeable list "
+				  "(free %d dirty %d flags %d)", lprops->lnum,
+				  lprops->free, lprops->dirty, lprops->flags);
+			return -EINVAL;
+		}
+		if (lprops->flags & LPROPS_TAKEN) {
+			ubifs_err("taken LEB %d on freeable list "
+				  "(free %d dirty %d flags %d)", lprops->lnum,
+				  lprops->free, lprops->dirty, lprops->flags);
+			return -EINVAL;
+		}
+		i += 1;
+	}
+	if (i != c->freeable_cnt) {
+		ubifs_err("freeable list count %d expected %d", i,
+			  c->freeable_cnt);
+		return -EINVAL;
+	}
+
+	i = 0;
+	list_for_each(pos, &c->idx_gc)
+		i += 1;
+	if (i != c->idx_gc_cnt) {
+		ubifs_err("idx_gc list count %d expected %d", i,
+			  c->idx_gc_cnt);
+		return -EINVAL;
+	}
+
+	list_for_each_entry(lprops, &c->frdi_idx_list, list) {
+		if (lprops->free + lprops->dirty != c->leb_size) {
+			ubifs_err("non-freeable LEB %d on frdi_idx list "
+				  "(free %d dirty %d flags %d)", lprops->lnum,
+				  lprops->free, lprops->dirty, lprops->flags);
+			return -EINVAL;
+		}
+		if (lprops->flags & LPROPS_TAKEN) {
+			ubifs_err("taken LEB %d on frdi_idx list "
+				  "(free %d dirty %d flags %d)", lprops->lnum,
+				  lprops->free, lprops->dirty, lprops->flags);
+			return -EINVAL;
+		}
+		if (!(lprops->flags & LPROPS_INDEX)) {
+			ubifs_err("non-index LEB %d on frdi_idx list "
+				  "(free %d dirty %d flags %d)", lprops->lnum,
+				  lprops->free, lprops->dirty, lprops->flags);
+			return -EINVAL;
+		}
+	}
+
+	for (cat = 1; cat <= LPROPS_HEAP_CNT; cat++) {
+		struct ubifs_lpt_heap *heap = &c->lpt_heap[cat - 1];
+
+		for (i = 0; i < heap->cnt; i++) {
+			lprops = heap->arr[i];
+			if (!lprops) {
+				ubifs_err("null ptr in LPT heap cat %d", cat);
+				return -EINVAL;
+			}
+			if (lprops->hpos != i) {
+				ubifs_err("bad ptr in LPT heap cat %d", cat);
+				return -EINVAL;
+			}
+			if (lprops->flags & LPROPS_TAKEN) {
+				ubifs_err("taken LEB in LPT heap cat %d", cat);
+				return -EINVAL;
+			}
+		}
+	}
+
+	return 0;
+}
+
+void dbg_check_heap(struct ubifs_info *c, struct ubifs_lpt_heap *heap, int cat,
+		    int add_pos)
+{
+	int i = 0, j, err = 0;
+
+	if (!(ubifs_chk_flags & (UBIFS_CHK_GEN | UBIFS_CHK_LPROPS)))
+		return;
+
+	for (i = 0; i < heap->cnt; i++) {
+		struct ubifs_lprops *lprops = heap->arr[i];
+		struct ubifs_lprops *lp;
+
+		if (i != add_pos)
+			if ((lprops->flags & LPROPS_CAT_MASK) != cat) {
+				err = 1;
+				goto out;
+			}
+		if (lprops->hpos != i) {
+			err = 2;
+			goto out;
+		}
+		lp = ubifs_lpt_lookup(c, lprops->lnum);
+		if (IS_ERR(lp)) {
+			err = 3;
+			goto out;
+		}
+		if (lprops != lp) {
+			dbg_msg("lprops %zx lp %zx lprops->lnum %d lp->lnum %d",
+				(size_t)lprops, (size_t)lp, lprops->lnum,
+				lp->lnum);
+			err = 4;
+			goto out;
+		}
+		for (j = 0; j < i; j++) {
+			lp = heap->arr[j];
+			if (lp == lprops) {
+				err = 5;
+				goto out;
+			}
+			if (lp->lnum == lprops->lnum) {
+				err = 6;
+				goto out;
+			}
+		}
+	}
+out:
+	if (err) {
+		dbg_msg("failed cat %d hpos %d err %d", cat, i, err);
+		dbg_dump_stack();
+		dbg_dump_heap(c, heap, cat);
+	}
+}
+
+/**
+ * struct scan_check_data - data provided to scan callback function.
+ * @lst: LEB properties statistics
+ * @err: error code
+ */
+struct scan_check_data {
+	struct ubifs_lp_stats lst;
+	int err;
+};
+
+/**
+ * scan_check_cb - scan callback.
+ * @c: the UBIFS file-system description object
+ * @lp: LEB properties to scan
+ * @in_tree: whether the LEB properties are in main memory
+ * @data: information passed to and from the caller of the scan
+ *
+ * This function returns a code that indicates whether the scan should continue
+ * (%LPT_SCAN_CONTINUE), whether the LEB properties should be added to the tree
+ * in main memory (%LPT_SCAN_ADD), or whether the scan should stop
+ * (%LPT_SCAN_STOP).
+ */
+static int scan_check_cb(struct ubifs_info *c,
+			 const struct ubifs_lprops *lp, int in_tree,
+			 struct scan_check_data *data)
+{
+	struct ubifs_scan_leb *sleb;
+	struct ubifs_scan_node *snod;
+	struct ubifs_lp_stats *lst = &data->lst;
+	int cat, lnum = lp->lnum, is_idx = 0, used = 0, free, dirty;
+
+	cat = lp->flags & LPROPS_CAT_MASK;
+	if (cat != LPROPS_UNCAT) {
+		cat = ubifs_categorize_lprops(c, lp);
+		if (cat != (lp->flags & LPROPS_CAT_MASK)) {
+			ubifs_err("bad LEB category %d expected %d",
+				  (lp->flags & LPROPS_CAT_MASK), cat);
+			goto out;
+		}
+	}
+
+	/* Check lp is on its category list (if it has one) */
+	if (in_tree) {
+		struct list_head *list = NULL;
+
+		switch (cat) {
+		case LPROPS_EMPTY:
+			list = &c->empty_list;
+			break;
+		case LPROPS_FREEABLE:
+			list = &c->freeable_list;
+			break;
+		case LPROPS_FRDI_IDX:
+			list = &c->frdi_idx_list;
+			break;
+		case LPROPS_UNCAT:
+			list = &c->uncat_list;
+			break;
+		}
+		if (list) {
+			struct ubifs_lprops *lprops;
+			int found = 0;
+
+			list_for_each_entry(lprops, list, list) {
+				if (lprops == lp) {
+					found = 1;
+					break;
+				}
+			}
+			if (!found) {
+				ubifs_err("bad LPT list (category %d)", cat);
+				goto out;
+			}
+		}
+	}
+
+	/* Check lp is on its category heap (if it has one) */
+	if (in_tree && cat > 0 && cat <= LPROPS_HEAP_CNT) {
+		struct ubifs_lpt_heap *heap = &c->lpt_heap[cat - 1];
+
+		if ((lp->hpos != -1 && heap->arr[lp->hpos]->lnum != lnum) ||
+		    lp != heap->arr[lp->hpos]) {
+			ubifs_err("bad LPT heap (category %d)", cat);
+			goto out;
+		}
+	}
+
+	sleb = ubifs_scan(c, lnum, 0, c->dbg_buf);
+	if (IS_ERR(sleb)) {
+		/*
+		 * After an unclean unmount, empty and freeable LEBs
+		 * may contain garbage.
+		 */
+		if (lp->free == c->leb_size) {
+			ubifs_err("scan errors were in empty LEB "
+				  "- continuing checking");
+			lst->empty_lebs += 1;
+			lst->total_free += c->leb_size;
+			lst->total_dark += calc_dark(c, c->leb_size);
+			return LPT_SCAN_CONTINUE;
+		}
+
+		if (lp->free + lp->dirty == c->leb_size &&
+		    !(lp->flags & LPROPS_INDEX)) {
+			ubifs_err("scan errors were in freeable LEB "
+				  "- continuing checking");
+			lst->total_free  += lp->free;
+			lst->total_dirty += lp->dirty;
+			lst->total_dark  +=  calc_dark(c, c->leb_size);
+			return LPT_SCAN_CONTINUE;
+		}
+		data->err = PTR_ERR(sleb);
+		return LPT_SCAN_STOP;
+	}
+
+	is_idx = -1;
+	list_for_each_entry(snod, &sleb->nodes, list) {
+		int found, level = 0;
+
+		cond_resched();
+
+		if (is_idx == -1)
+			is_idx = (snod->type == UBIFS_IDX_NODE) ? 1 : 0;
+
+		if (is_idx && snod->type != UBIFS_IDX_NODE) {
+			ubifs_err("indexing node in data LEB %d:%d",
+				  lnum, snod->offs);
+			goto out_destroy;
+		}
+
+		if (snod->type == UBIFS_IDX_NODE) {
+			struct ubifs_idx_node *idx = snod->node;
+
+			key_read(c, ubifs_idx_key(c, idx), &snod->key);
+			level = le16_to_cpu(idx->level);
+		}
+
+		found = ubifs_tnc_has_node(c, &snod->key, level, lnum,
+					   snod->offs, is_idx);
+		if (found) {
+			if (found < 0)
+				goto out_destroy;
+			used += ALIGN(snod->len, 8);
+		}
+	}
+
+	free = c->leb_size - sleb->endpt;
+	dirty = sleb->endpt - used;
+
+	if (free > c->leb_size || free < 0 || dirty > c->leb_size ||
+	    dirty < 0) {
+		ubifs_err("bad calculated accounting for LEB %d: "
+			  "free %d, dirty %d", lnum, free, dirty);
+		goto out_destroy;
+	}
+
+	if (lp->free + lp->dirty == c->leb_size &&
+	    free + dirty == c->leb_size)
+		if ((is_idx && !(lp->flags & LPROPS_INDEX)) ||
+		    (!is_idx && free == c->leb_size) ||
+		    lp->free == c->leb_size) {
+			/*
+			 * Empty or freeable LEBs could contain index
+			 * nodes from an uncompleted commit due to an
+			 * unclean unmount. Or they could be empty for
+			 * the same reason. Or it may simply not have been
+			 * unmapped.
+			 */
+			free = lp->free;
+			dirty = lp->dirty;
+			is_idx = 0;
+		    }
+
+	if (is_idx && lp->free + lp->dirty == free + dirty &&
+	    lnum != c->ihead_lnum) {
+		/*
+		 * After an unclean unmount, an index LEB could have a different
+		 * amount of free space than the value recorded by lprops. That
+		 * is because the in-the-gaps method may use free space or
+		 * create free space (as a side-effect of using ubi_leb_change
+		 * and not writing the whole LEB). The incorrect free space
+		 * value is not a problem because the index is only ever
+		 * allocated empty LEBs, so there will never be an attempt to
+		 * write to the free space at the end of an index LEB - except
+		 * by the in-the-gaps method for which it is not a problem.
+		 */
+		free = lp->free;
+		dirty = lp->dirty;
+	}
+
+	if (lp->free != free || lp->dirty != dirty)
+		goto out_print;
+
+	if (is_idx && !(lp->flags & LPROPS_INDEX)) {
+		if (free == c->leb_size)
+			/* Free but not unmapped LEB, it's fine */
+			is_idx = 0;
+		else {
+			ubifs_err("indexing node without indexing "
+				  "flag");
+			goto out_print;
+		}
+	}
+
+	if (!is_idx && (lp->flags & LPROPS_INDEX)) {
+		ubifs_err("data node with indexing flag");
+		goto out_print;
+	}
+
+	if (free == c->leb_size)
+		lst->empty_lebs += 1;
+
+	if (is_idx)
+		lst->idx_lebs += 1;
+
+	if (!(lp->flags & LPROPS_INDEX))
+		lst->total_used += c->leb_size - free - dirty;
+	lst->total_free += free;
+	lst->total_dirty += dirty;
+
+	if (!(lp->flags & LPROPS_INDEX)) {
+		int spc = free + dirty;
+
+		if (spc < c->dead_wm)
+			lst->total_dead += spc;
+		else
+			lst->total_dark += calc_dark(c, spc);
+	}
+
+	ubifs_scan_destroy(sleb);
+
+	return LPT_SCAN_CONTINUE;
+
+out_print:
+	ubifs_err("bad accounting of LEB %d: free %d, dirty %d flags %#x, "
+		  "should be free %d, dirty %d",
+		  lnum, lp->free, lp->dirty, lp->flags, free, dirty);
+	dbg_dump_leb(c, lnum);
+out_destroy:
+	ubifs_scan_destroy(sleb);
+out:
+	data->err = -EINVAL;
+	return LPT_SCAN_STOP;
+}
+
+/**
+ * dbg_check_lprops - check all LEB properties.
+ * @c: UBIFS file-system description object
+ *
+ * This function checks all LEB properties and makes sure they are all correct.
+ * It returns zero if everything is fine, %-EINVAL if there is an inconsistency
+ * and other negative error codes in case of other errors. This function is
+ * called while the file system is locked (because of commit start), so no
+ * additional locking is required. Note that locking the LPT mutex would cause
+ * a circular lock dependency with the TNC mutex.
+ */
+int dbg_check_lprops(struct ubifs_info *c)
+{
+	int i, err;
+	struct scan_check_data data;
+	struct ubifs_lp_stats *lst = &data.lst;
+
+	if (!(ubifs_chk_flags & UBIFS_CHK_LPROPS))
+		return 0;
+
+	/*
+	 * As we are going to scan the media, the write buffers have to be
+	 * synchronized.
+	 */
+	for (i = 0; i < c->jhead_cnt; i++) {
+		err = ubifs_wbuf_sync(&c->jheads[i].wbuf);
+		if (err)
+			return err;
+	}
+
+	memset(lst, 0, sizeof(struct ubifs_lp_stats));
+
+	data.err = 0;
+	err = ubifs_lpt_scan_nolock(c, c->main_first, c->leb_cnt - 1,
+				    (ubifs_lpt_scan_callback)scan_check_cb,
+				    &data);
+	if (err && err != -ENOSPC)
+		goto out;
+	if (data.err) {
+		err = data.err;
+		goto out;
+	}
+
+	if (lst->empty_lebs != c->lst.empty_lebs ||
+	    lst->idx_lebs != c->lst.idx_lebs ||
+	    lst->total_free != c->lst.total_free ||
+	    lst->total_dirty != c->lst.total_dirty ||
+	    lst->total_used != c->lst.total_used) {
+		ubifs_err("bad overall accounting");
+		ubifs_err("calculated: empty_lebs %d, idx_lebs %d, "
+			  "total_free %lld, total_dirty %lld, total_used %lld",
+			  lst->empty_lebs, lst->idx_lebs, lst->total_free,
+			  lst->total_dirty, lst->total_used);
+		ubifs_err("read from lprops: empty_lebs %d, idx_lebs %d, "
+			  "total_free %lld, total_dirty %lld, total_used %lld",
+			  c->lst.empty_lebs, c->lst.idx_lebs, c->lst.total_free,
+			  c->lst.total_dirty, c->lst.total_used);
+		err = -EINVAL;
+		goto out;
+	}
+
+	if (lst->total_dead != c->lst.total_dead ||
+	    lst->total_dark != c->lst.total_dark) {
+		ubifs_err("bad dead/dark space accounting");
+		ubifs_err("calculated: total_dead %lld, total_dark %lld",
+			  lst->total_dead, lst->total_dark);
+		ubifs_err("read from lprops: total_dead %lld, total_dark %lld",
+			  c->lst.total_dead, c->lst.total_dark);
+		err = -EINVAL;
+		goto out;
+	}
+
+	err = dbg_check_cats(c);
+out:
+	return err;
+}
+
+#endif /* CONFIG_UBIFS_FS_DEBUG */
diff --git a/fs/ubifs/lpt.c b/fs/ubifs/lpt.c
new file mode 100644
index 00000000000..9ff2463177e
--- /dev/null
+++ b/fs/ubifs/lpt.c
@@ -0,0 +1,2243 @@
+/*
+ * This file is part of UBIFS.
+ *
+ * Copyright (C) 2006-2008 Nokia Corporation.
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 as published by
+ * the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
+ * more details.
+ *
+ * You should have received a copy of the GNU General Public License along with
+ * this program; if not, write to the Free Software Foundation, Inc., 51
+ * Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
+ *
+ * Authors: Adrian Hunter
+ *          Artem Bityutskiy (Битюцкий Артём)
+ */
+
+/*
+ * This file implements the LEB properties tree (LPT) area. The LPT area
+ * contains the LEB properties tree, a table of LPT area eraseblocks (ltab), and
+ * (for the "big" model) a table of saved LEB numbers (lsave). The LPT area sits
+ * between the log and the orphan area.
+ *
+ * The LPT area is like a miniature self-contained file system. It is required
+ * that it never runs out of space, is fast to access and update, and scales
+ * logarithmically. The LEB properties tree is implemented as a wandering tree
+ * much like the TNC, and the LPT area has its own garbage collection.
+ *
+ * The LPT has two slightly different forms called the "small model" and the
+ * "big model". The small model is used when the entire LEB properties table
+ * can be written into a single eraseblock. In that case, garbage collection
+ * consists of just writing the whole table, which therefore makes all other
+ * eraseblocks reusable. In the case of the big model, dirty eraseblocks are
+ * selected for garbage collection, which consists are marking the nodes in
+ * that LEB as dirty, and then only the dirty nodes are written out. Also, in
+ * the case of the big model, a table of LEB numbers is saved so that the entire
+ * LPT does not to be scanned looking for empty eraseblocks when UBIFS is first
+ * mounted.
+ */
+
+#include <linux/crc16.h>
+#include "ubifs.h"
+
+/**
+ * do_calc_lpt_geom - calculate sizes for the LPT area.
+ * @c: the UBIFS file-system description object
+ *
+ * Calculate the sizes of LPT bit fields, nodes, and tree, based on the
+ * properties of the flash and whether LPT is "big" (c->big_lpt).
+ */
+static void do_calc_lpt_geom(struct ubifs_info *c)
+{
+	int i, n, bits, per_leb_wastage, max_pnode_cnt;
+	long long sz, tot_wastage;
+
+	n = c->main_lebs + c->max_leb_cnt - c->leb_cnt;
+	max_pnode_cnt = DIV_ROUND_UP(n, UBIFS_LPT_FANOUT);
+
+	c->lpt_hght = 1;
+	n = UBIFS_LPT_FANOUT;
+	while (n < max_pnode_cnt) {
+		c->lpt_hght += 1;
+		n <<= UBIFS_LPT_FANOUT_SHIFT;
+	}
+
+	c->pnode_cnt = DIV_ROUND_UP(c->main_lebs, UBIFS_LPT_FANOUT);
+
+	n = DIV_ROUND_UP(c->pnode_cnt, UBIFS_LPT_FANOUT);
+	c->nnode_cnt = n;
+	for (i = 1; i < c->lpt_hght; i++) {
+		n = DIV_ROUND_UP(n, UBIFS_LPT_FANOUT);
+		c->nnode_cnt += n;
+	}
+
+	c->space_bits = fls(c->leb_size) - 3;
+	c->lpt_lnum_bits = fls(c->lpt_lebs);
+	c->lpt_offs_bits = fls(c->leb_size - 1);
+	c->lpt_spc_bits = fls(c->leb_size);
+
+	n = DIV_ROUND_UP(c->max_leb_cnt, UBIFS_LPT_FANOUT);
+	c->pcnt_bits = fls(n - 1);
+
+	c->lnum_bits = fls(c->max_leb_cnt - 1);
+
+	bits = UBIFS_LPT_CRC_BITS + UBIFS_LPT_TYPE_BITS +
+	       (c->big_lpt ? c->pcnt_bits : 0) +
+	       (c->space_bits * 2 + 1) * UBIFS_LPT_FANOUT;
+	c->pnode_sz = (bits + 7) / 8;
+
+	bits = UBIFS_LPT_CRC_BITS + UBIFS_LPT_TYPE_BITS +
+	       (c->big_lpt ? c->pcnt_bits : 0) +
+	       (c->lpt_lnum_bits + c->lpt_offs_bits) * UBIFS_LPT_FANOUT;
+	c->nnode_sz = (bits + 7) / 8;
+
+	bits = UBIFS_LPT_CRC_BITS + UBIFS_LPT_TYPE_BITS +
+	       c->lpt_lebs * c->lpt_spc_bits * 2;
+	c->ltab_sz = (bits + 7) / 8;
+
+	bits = UBIFS_LPT_CRC_BITS + UBIFS_LPT_TYPE_BITS +
+	       c->lnum_bits * c->lsave_cnt;
+	c->lsave_sz = (bits + 7) / 8;
+
+	/* Calculate the minimum LPT size */
+	c->lpt_sz = (long long)c->pnode_cnt * c->pnode_sz;
+	c->lpt_sz += (long long)c->nnode_cnt * c->nnode_sz;
+	c->lpt_sz += c->ltab_sz;
+	c->lpt_sz += c->lsave_sz;
+
+	/* Add wastage */
+	sz = c->lpt_sz;
+	per_leb_wastage = max_t(int, c->pnode_sz, c->nnode_sz);
+	sz += per_leb_wastage;
+	tot_wastage = per_leb_wastage;
+	while (sz > c->leb_size) {
+		sz += per_leb_wastage;
+		sz -= c->leb_size;
+		tot_wastage += per_leb_wastage;
+	}
+	tot_wastage += ALIGN(sz, c->min_io_size) - sz;
+	c->lpt_sz += tot_wastage;
+}
+
+/**
+ * ubifs_calc_lpt_geom - calculate and check sizes for the LPT area.
+ * @c: the UBIFS file-system description object
+ *
+ * This function returns %0 on success and a negative error code on failure.
+ */
+int ubifs_calc_lpt_geom(struct ubifs_info *c)
+{
+	int lebs_needed;
+	uint64_t sz;
+
+	do_calc_lpt_geom(c);
+
+	/* Verify that lpt_lebs is big enough */
+	sz = c->lpt_sz * 2; /* Must have at least 2 times the size */
+	sz += c->leb_size - 1;
+	do_div(sz, c->leb_size);
+	lebs_needed = sz;
+	if (lebs_needed > c->lpt_lebs) {
+		ubifs_err("too few LPT LEBs");
+		return -EINVAL;
+	}
+
+	/* Verify that ltab fits in a single LEB (since ltab is a single node */
+	if (c->ltab_sz > c->leb_size) {
+		ubifs_err("LPT ltab too big");
+		return -EINVAL;
+	}
+
+	c->check_lpt_free = c->big_lpt;
+
+	return 0;
+}
+
+/**
+ * calc_dflt_lpt_geom - calculate default LPT geometry.
+ * @c: the UBIFS file-system description object
+ * @main_lebs: number of main area LEBs is passed and returned here
+ * @big_lpt: whether the LPT area is "big" is returned here
+ *
+ * The size of the LPT area depends on parameters that themselves are dependent
+ * on the size of the LPT area. This function, successively recalculates the LPT
+ * area geometry until the parameters and resultant geometry are consistent.
+ *
+ * This function returns %0 on success and a negative error code on failure.
+ */
+static int calc_dflt_lpt_geom(struct ubifs_info *c, int *main_lebs,
+			      int *big_lpt)
+{
+	int i, lebs_needed;
+	uint64_t sz;
+
+	/* Start by assuming the minimum number of LPT LEBs */
+	c->lpt_lebs = UBIFS_MIN_LPT_LEBS;
+	c->main_lebs = *main_lebs - c->lpt_lebs;
+	if (c->main_lebs <= 0)
+		return -EINVAL;
+
+	/* And assume we will use the small LPT model */
+	c->big_lpt = 0;
+
+	/*
+	 * Calculate the geometry based on assumptions above and then see if it
+	 * makes sense
+	 */
+	do_calc_lpt_geom(c);
+
+	/* Small LPT model must have lpt_sz < leb_size */
+	if (c->lpt_sz > c->leb_size) {
+		/* Nope, so try again using big LPT model */
+		c->big_lpt = 1;
+		do_calc_lpt_geom(c);
+	}
+
+	/* Now check there are enough LPT LEBs */
+	for (i = 0; i < 64 ; i++) {
+		sz = c->lpt_sz * 4; /* Allow 4 times the size */
+		sz += c->leb_size - 1;
+		do_div(sz, c->leb_size);
+		lebs_needed = sz;
+		if (lebs_needed > c->lpt_lebs) {
+			/* Not enough LPT LEBs so try again with more */
+			c->lpt_lebs = lebs_needed;
+			c->main_lebs = *main_lebs - c->lpt_lebs;
+			if (c->main_lebs <= 0)
+				return -EINVAL;
+			do_calc_lpt_geom(c);
+			continue;
+		}
+		if (c->ltab_sz > c->leb_size) {
+			ubifs_err("LPT ltab too big");
+			return -EINVAL;
+		}
+		*main_lebs = c->main_lebs;
+		*big_lpt = c->big_lpt;
+		return 0;
+	}
+	return -EINVAL;
+}
+
+/**
+ * pack_bits - pack bit fields end-to-end.
+ * @addr: address at which to pack (passed and next address returned)
+ * @pos: bit position at which to pack (passed and next position returned)
+ * @val: value to pack
+ * @nrbits: number of bits of value to pack (1-32)
+ */
+static void pack_bits(uint8_t **addr, int *pos, uint32_t val, int nrbits)
+{
+	uint8_t *p = *addr;
+	int b = *pos;
+
+	ubifs_assert(nrbits > 0);
+	ubifs_assert(nrbits <= 32);
+	ubifs_assert(*pos >= 0);
+	ubifs_assert(*pos < 8);
+	ubifs_assert((val >> nrbits) == 0 || nrbits == 32);
+	if (b) {
+		*p |= ((uint8_t)val) << b;
+		nrbits += b;
+		if (nrbits > 8) {
+			*++p = (uint8_t)(val >>= (8 - b));
+			if (nrbits > 16) {
+				*++p = (uint8_t)(val >>= 8);
+				if (nrbits > 24) {
+					*++p = (uint8_t)(val >>= 8);
+					if (nrbits > 32)
+						*++p = (uint8_t)(val >>= 8);
+				}
+			}
+		}
+	} else {
+		*p = (uint8_t)val;
+		if (nrbits > 8) {
+			*++p = (uint8_t)(val >>= 8);
+			if (nrbits > 16) {
+				*++p = (uint8_t)(val >>= 8);
+				if (nrbits > 24)
+					*++p = (uint8_t)(val >>= 8);
+			}
+		}
+	}
+	b = nrbits & 7;
+	if (b == 0)
+		p++;
+	*addr = p;
+	*pos = b;
+}
+
+/**
+ * ubifs_unpack_bits - unpack bit fields.
+ * @addr: address at which to unpack (passed and next address returned)
+ * @pos: bit position at which to unpack (passed and next position returned)
+ * @nrbits: number of bits of value to unpack (1-32)
+ *
+ * This functions returns the value unpacked.
+ */
+uint32_t ubifs_unpack_bits(uint8_t **addr, int *pos, int nrbits)
+{
+	const int k = 32 - nrbits;
+	uint8_t *p = *addr;
+	int b = *pos;
+	uint32_t val;
+
+	ubifs_assert(nrbits > 0);
+	ubifs_assert(nrbits <= 32);
+	ubifs_assert(*pos >= 0);
+	ubifs_assert(*pos < 8);
+	if (b) {
+		val = p[1] | ((uint32_t)p[2] << 8) | ((uint32_t)p[3] << 16) |
+		      ((uint32_t)p[4] << 24);
+		val <<= (8 - b);
+		val |= *p >> b;
+		nrbits += b;
+	} else
+		val = p[0] | ((uint32_t)p[1] << 8) | ((uint32_t)p[2] << 16) |
+		      ((uint32_t)p[3] << 24);
+	val <<= k;
+	val >>= k;
+	b = nrbits & 7;
+	p += nrbits / 8;
+	*addr = p;
+	*pos = b;
+	ubifs_assert((val >> nrbits) == 0 || nrbits - b == 32);
+	return val;
+}
+
+/**
+ * ubifs_pack_pnode - pack all the bit fields of a pnode.
+ * @c: UBIFS file-system description object
+ * @buf: buffer into which to pack
+ * @pnode: pnode to pack
+ */
+void ubifs_pack_pnode(struct ubifs_info *c, void *buf,
+		      struct ubifs_pnode *pnode)
+{
+	uint8_t *addr = buf + UBIFS_LPT_CRC_BYTES;
+	int i, pos = 0;
+	uint16_t crc;
+
+	pack_bits(&addr, &pos, UBIFS_LPT_PNODE, UBIFS_LPT_TYPE_BITS);
+	if (c->big_lpt)
+		pack_bits(&addr, &pos, pnode->num, c->pcnt_bits);
+	for (i = 0; i < UBIFS_LPT_FANOUT; i++) {
+		pack_bits(&addr, &pos, pnode->lprops[i].free >> 3,
+			  c->space_bits);
+		pack_bits(&addr, &pos, pnode->lprops[i].dirty >> 3,
+			  c->space_bits);
+		if (pnode->lprops[i].flags & LPROPS_INDEX)
+			pack_bits(&addr, &pos, 1, 1);
+		else
+			pack_bits(&addr, &pos, 0, 1);
+	}
+	crc = crc16(-1, buf + UBIFS_LPT_CRC_BYTES,
+		    c->pnode_sz - UBIFS_LPT_CRC_BYTES);
+	addr = buf;
+	pos = 0;
+	pack_bits(&addr, &pos, crc, UBIFS_LPT_CRC_BITS);
+}
+
+/**
+ * ubifs_pack_nnode - pack all the bit fields of a nnode.
+ * @c: UBIFS file-system description object
+ * @buf: buffer into which to pack
+ * @nnode: nnode to pack
+ */
+void ubifs_pack_nnode(struct ubifs_info *c, void *buf,
+		      struct ubifs_nnode *nnode)
+{
+	uint8_t *addr = buf + UBIFS_LPT_CRC_BYTES;
+	int i, pos = 0;
+	uint16_t crc;
+
+	pack_bits(&addr, &pos, UBIFS_LPT_NNODE, UBIFS_LPT_TYPE_BITS);
+	if (c->big_lpt)
+		pack_bits(&addr, &pos, nnode->num, c->pcnt_bits);
+	for (i = 0; i < UBIFS_LPT_FANOUT; i++) {
+		int lnum = nnode->nbranch[i].lnum;
+
+		if (lnum == 0)
+			lnum = c->lpt_last + 1;
+		pack_bits(&addr, &pos, lnum - c->lpt_first, c->lpt_lnum_bits);
+		pack_bits(&addr, &pos, nnode->nbranch[i].offs,
+			  c->lpt_offs_bits);
+	}
+	crc = crc16(-1, buf + UBIFS_LPT_CRC_BYTES,
+		    c->nnode_sz - UBIFS_LPT_CRC_BYTES);
+	addr = buf;
+	pos = 0;
+	pack_bits(&addr, &pos, crc, UBIFS_LPT_CRC_BITS);
+}
+
+/**
+ * ubifs_pack_ltab - pack the LPT's own lprops table.
+ * @c: UBIFS file-system description object
+ * @buf: buffer into which to pack
+ * @ltab: LPT's own lprops table to pack
+ */
+void ubifs_pack_ltab(struct ubifs_info *c, void *buf,
+		     struct ubifs_lpt_lprops *ltab)
+{
+	uint8_t *addr = buf + UBIFS_LPT_CRC_BYTES;
+	int i, pos = 0;
+	uint16_t crc;
+
+	pack_bits(&addr, &pos, UBIFS_LPT_LTAB, UBIFS_LPT_TYPE_BITS);
+	for (i = 0; i < c->lpt_lebs; i++) {
+		pack_bits(&addr, &pos, ltab[i].free, c->lpt_spc_bits);
+		pack_bits(&addr, &pos, ltab[i].dirty, c->lpt_spc_bits);
+	}
+	crc = crc16(-1, buf + UBIFS_LPT_CRC_BYTES,
+		    c->ltab_sz - UBIFS_LPT_CRC_BYTES);
+	addr = buf;
+	pos = 0;
+	pack_bits(&addr, &pos, crc, UBIFS_LPT_CRC_BITS);
+}
+
+/**
+ * ubifs_pack_lsave - pack the LPT's save table.
+ * @c: UBIFS file-system description object
+ * @buf: buffer into which to pack
+ * @lsave: LPT's save table to pack
+ */
+void ubifs_pack_lsave(struct ubifs_info *c, void *buf, int *lsave)
+{
+	uint8_t *addr = buf + UBIFS_LPT_CRC_BYTES;
+	int i, pos = 0;
+	uint16_t crc;
+
+	pack_bits(&addr, &pos, UBIFS_LPT_LSAVE, UBIFS_LPT_TYPE_BITS);
+	for (i = 0; i < c->lsave_cnt; i++)
+		pack_bits(&addr, &pos, lsave[i], c->lnum_bits);
+	crc = crc16(-1, buf + UBIFS_LPT_CRC_BYTES,
+		    c->lsave_sz - UBIFS_LPT_CRC_BYTES);
+	addr = buf;
+	pos = 0;
+	pack_bits(&addr, &pos, crc, UBIFS_LPT_CRC_BITS);
+}
+
+/**
+ * ubifs_add_lpt_dirt - add dirty space to LPT LEB properties.
+ * @c: UBIFS file-system description object
+ * @lnum: LEB number to which to add dirty space
+ * @dirty: amount of dirty space to add
+ */
+void ubifs_add_lpt_dirt(struct ubifs_info *c, int lnum, int dirty)
+{
+	if (!dirty || !lnum)
+		return;
+	dbg_lp("LEB %d add %d to %d",
+	       lnum, dirty, c->ltab[lnum - c->lpt_first].dirty);
+	ubifs_assert(lnum >= c->lpt_first && lnum <= c->lpt_last);
+	c->ltab[lnum - c->lpt_first].dirty += dirty;
+}
+
+/**
+ * set_ltab - set LPT LEB properties.
+ * @c: UBIFS file-system description object
+ * @lnum: LEB number
+ * @free: amount of free space
+ * @dirty: amount of dirty space
+ */
+static void set_ltab(struct ubifs_info *c, int lnum, int free, int dirty)
+{
+	dbg_lp("LEB %d free %d dirty %d to %d %d",
+	       lnum, c->ltab[lnum - c->lpt_first].free,
+	       c->ltab[lnum - c->lpt_first].dirty, free, dirty);
+	ubifs_assert(lnum >= c->lpt_first && lnum <= c->lpt_last);
+	c->ltab[lnum - c->lpt_first].free = free;
+	c->ltab[lnum - c->lpt_first].dirty = dirty;
+}
+
+/**
+ * ubifs_add_nnode_dirt - add dirty space to LPT LEB properties.
+ * @c: UBIFS file-system description object
+ * @nnode: nnode for which to add dirt
+ */
+void ubifs_add_nnode_dirt(struct ubifs_info *c, struct ubifs_nnode *nnode)
+{
+	struct ubifs_nnode *np = nnode->parent;
+
+	if (np)
+		ubifs_add_lpt_dirt(c, np->nbranch[nnode->iip].lnum,
+				   c->nnode_sz);
+	else {
+		ubifs_add_lpt_dirt(c, c->lpt_lnum, c->nnode_sz);
+		if (!(c->lpt_drty_flgs & LTAB_DIRTY)) {
+			c->lpt_drty_flgs |= LTAB_DIRTY;
+			ubifs_add_lpt_dirt(c, c->ltab_lnum, c->ltab_sz);
+		}
+	}
+}
+
+/**
+ * add_pnode_dirt - add dirty space to LPT LEB properties.
+ * @c: UBIFS file-system description object
+ * @pnode: pnode for which to add dirt
+ */
+static void add_pnode_dirt(struct ubifs_info *c, struct ubifs_pnode *pnode)
+{
+	ubifs_add_lpt_dirt(c, pnode->parent->nbranch[pnode->iip].lnum,
+			   c->pnode_sz);
+}
+
+/**
+ * calc_nnode_num - calculate nnode number.
+ * @row: the row in the tree (root is zero)
+ * @col: the column in the row (leftmost is zero)
+ *
+ * The nnode number is a number that uniquely identifies a nnode and can be used
+ * easily to traverse the tree from the root to that nnode.
+ *
+ * This function calculates and returns the nnode number for the nnode at @row
+ * and @col.
+ */
+static int calc_nnode_num(int row, int col)
+{
+	int num, bits;
+
+	num = 1;
+	while (row--) {
+		bits = (col & (UBIFS_LPT_FANOUT - 1));
+		col >>= UBIFS_LPT_FANOUT_SHIFT;
+		num <<= UBIFS_LPT_FANOUT_SHIFT;
+		num |= bits;
+	}
+	return num;
+}
+
+/**
+ * calc_nnode_num_from_parent - calculate nnode number.
+ * @c: UBIFS file-system description object
+ * @parent: parent nnode
+ * @iip: index in parent
+ *
+ * The nnode number is a number that uniquely identifies a nnode and can be used
+ * easily to traverse the tree from the root to that nnode.
+ *
+ * This function calculates and returns the nnode number based on the parent's
+ * nnode number and the index in parent.
+ */
+static int calc_nnode_num_from_parent(struct ubifs_info *c,
+				      struct ubifs_nnode *parent, int iip)
+{
+	int num, shft;
+
+	if (!parent)
+		return 1;
+	shft = (c->lpt_hght - parent->level) * UBIFS_LPT_FANOUT_SHIFT;
+	num = parent->num ^ (1 << shft);
+	num |= (UBIFS_LPT_FANOUT + iip) << shft;
+	return num;
+}
+
+/**
+ * calc_pnode_num_from_parent - calculate pnode number.
+ * @c: UBIFS file-system description object
+ * @parent: parent nnode
+ * @iip: index in parent
+ *
+ * The pnode number is a number that uniquely identifies a pnode and can be used
+ * easily to traverse the tree from the root to that pnode.
+ *
+ * This function calculates and returns the pnode number based on the parent's
+ * nnode number and the index in parent.
+ */
+static int calc_pnode_num_from_parent(struct ubifs_info *c,
+				      struct ubifs_nnode *parent, int iip)
+{
+	int i, n = c->lpt_hght - 1, pnum = parent->num, num = 0;
+
+	for (i = 0; i < n; i++) {
+		num <<= UBIFS_LPT_FANOUT_SHIFT;
+		num |= pnum & (UBIFS_LPT_FANOUT - 1);
+		pnum >>= UBIFS_LPT_FANOUT_SHIFT;
+	}
+	num <<= UBIFS_LPT_FANOUT_SHIFT;
+	num |= iip;
+	return num;
+}
+
+/**
+ * ubifs_create_dflt_lpt - create default LPT.
+ * @c: UBIFS file-system description object
+ * @main_lebs: number of main area LEBs is passed and returned here
+ * @lpt_first: LEB number of first LPT LEB
+ * @lpt_lebs: number of LEBs for LPT is passed and returned here
+ * @big_lpt: use big LPT model is passed and returned here
+ *
+ * This function returns %0 on success and a negative error code on failure.
+ */
+int ubifs_create_dflt_lpt(struct ubifs_info *c, int *main_lebs, int lpt_first,
+			  int *lpt_lebs, int *big_lpt)
+{
+	int lnum, err = 0, node_sz, iopos, i, j, cnt, len, alen, row;
+	int blnum, boffs, bsz, bcnt;
+	struct ubifs_pnode *pnode = NULL;
+	struct ubifs_nnode *nnode = NULL;
+	void *buf = NULL, *p;
+	struct ubifs_lpt_lprops *ltab = NULL;
+	int *lsave = NULL;
+
+	err = calc_dflt_lpt_geom(c, main_lebs, big_lpt);
+	if (err)
+		return err;
+	*lpt_lebs = c->lpt_lebs;
+
+	/* Needed by 'ubifs_pack_nnode()' and 'set_ltab()' */
+	c->lpt_first = lpt_first;
+	/* Needed by 'set_ltab()' */
+	c->lpt_last = lpt_first + c->lpt_lebs - 1;
+	/* Needed by 'ubifs_pack_lsave()' */
+	c->main_first = c->leb_cnt - *main_lebs;
+
+	lsave = kmalloc(sizeof(int) * c->lsave_cnt, GFP_KERNEL);
+	pnode = kzalloc(sizeof(struct ubifs_pnode), GFP_KERNEL);
+	nnode = kzalloc(sizeof(struct ubifs_nnode), GFP_KERNEL);
+	buf = vmalloc(c->leb_size);
+	ltab = vmalloc(sizeof(struct ubifs_lpt_lprops) * c->lpt_lebs);
+	if (!pnode || !nnode || !buf || !ltab || !lsave) {
+		err = -ENOMEM;
+		goto out;
+	}
+
+	ubifs_assert(!c->ltab);
+	c->ltab = ltab; /* Needed by set_ltab */
+
+	/* Initialize LPT's own lprops */
+	for (i = 0; i < c->lpt_lebs; i++) {
+		ltab[i].free = c->leb_size;
+		ltab[i].dirty = 0;
+		ltab[i].tgc = 0;
+		ltab[i].cmt = 0;
+	}
+
+	lnum = lpt_first;
+	p = buf;
+	/* Number of leaf nodes (pnodes) */
+	cnt = c->pnode_cnt;
+
+	/*
+	 * The first pnode contains the LEB properties for the LEBs that contain
+	 * the root inode node and the root index node of the index tree.
+	 */
+	node_sz = ALIGN(ubifs_idx_node_sz(c, 1), 8);
+	iopos = ALIGN(node_sz, c->min_io_size);
+	pnode->lprops[0].free = c->leb_size - iopos;
+	pnode->lprops[0].dirty = iopos - node_sz;
+	pnode->lprops[0].flags = LPROPS_INDEX;
+
+	node_sz = UBIFS_INO_NODE_SZ;
+	iopos = ALIGN(node_sz, c->min_io_size);
+	pnode->lprops[1].free = c->leb_size - iopos;
+	pnode->lprops[1].dirty = iopos - node_sz;
+
+	for (i = 2; i < UBIFS_LPT_FANOUT; i++)
+		pnode->lprops[i].free = c->leb_size;
+
+	/* Add first pnode */
+	ubifs_pack_pnode(c, p, pnode);
+	p += c->pnode_sz;
+	len = c->pnode_sz;
+	pnode->num += 1;
+
+	/* Reset pnode values for remaining pnodes */
+	pnode->lprops[0].free = c->leb_size;
+	pnode->lprops[0].dirty = 0;
+	pnode->lprops[0].flags = 0;
+
+	pnode->lprops[1].free = c->leb_size;
+	pnode->lprops[1].dirty = 0;
+
+	/*
+	 * To calculate the internal node branches, we keep information about
+	 * the level below.
+	 */
+	blnum = lnum; /* LEB number of level below */
+	boffs = 0; /* Offset of level below */
+	bcnt = cnt; /* Number of nodes in level below */
+	bsz = c->pnode_sz; /* Size of nodes in level below */
+
+	/* Add all remaining pnodes */
+	for (i = 1; i < cnt; i++) {
+		if (len + c->pnode_sz > c->leb_size) {
+			alen = ALIGN(len, c->min_io_size);
+			set_ltab(c, lnum, c->leb_size - alen, alen - len);
+			memset(p, 0xff, alen - len);
+			err = ubi_leb_change(c->ubi, lnum++, buf, alen,
+					     UBI_SHORTTERM);
+			if (err)
+				goto out;
+			p = buf;
+			len = 0;
+		}
+		ubifs_pack_pnode(c, p, pnode);
+		p += c->pnode_sz;
+		len += c->pnode_sz;
+		/*
+		 * pnodes are simply numbered left to right starting at zero,
+		 * which means the pnode number can be used easily to traverse
+		 * down the tree to the corresponding pnode.
+		 */
+		pnode->num += 1;
+	}
+
+	row = 0;
+	for (i = UBIFS_LPT_FANOUT; cnt > i; i <<= UBIFS_LPT_FANOUT_SHIFT)
+		row += 1;
+	/* Add all nnodes, one level at a time */
+	while (1) {
+		/* Number of internal nodes (nnodes) at next level */
+		cnt = DIV_ROUND_UP(cnt, UBIFS_LPT_FANOUT);
+		for (i = 0; i < cnt; i++) {
+			if (len + c->nnode_sz > c->leb_size) {
+				alen = ALIGN(len, c->min_io_size);
+				set_ltab(c, lnum, c->leb_size - alen,
+					    alen - len);
+				memset(p, 0xff, alen - len);
+				err = ubi_leb_change(c->ubi, lnum++, buf, alen,
+						     UBI_SHORTTERM);
+				if (err)
+					goto out;
+				p = buf;
+				len = 0;
+			}
+			/* Only 1 nnode at this level, so it is the root */
+			if (cnt == 1) {
+				c->lpt_lnum = lnum;
+				c->lpt_offs = len;
+			}
+			/* Set branches to the level below */
+			for (j = 0; j < UBIFS_LPT_FANOUT; j++) {
+				if (bcnt) {
+					if (boffs + bsz > c->leb_size) {
+						blnum += 1;
+						boffs = 0;
+					}
+					nnode->nbranch[j].lnum = blnum;
+					nnode->nbranch[j].offs = boffs;
+					boffs += bsz;
+					bcnt--;
+				} else {
+					nnode->nbranch[j].lnum = 0;
+					nnode->nbranch[j].offs = 0;
+				}
+			}
+			nnode->num = calc_nnode_num(row, i);
+			ubifs_pack_nnode(c, p, nnode);
+			p += c->nnode_sz;
+			len += c->nnode_sz;
+		}
+		/* Only 1 nnode at this level, so it is the root */
+		if (cnt == 1)
+			break;
+		/* Update the information about the level below */
+		bcnt = cnt;
+		bsz = c->nnode_sz;
+		row -= 1;
+	}
+
+	if (*big_lpt) {
+		/* Need to add LPT's save table */
+		if (len + c->lsave_sz > c->leb_size) {
+			alen = ALIGN(len, c->min_io_size);
+			set_ltab(c, lnum, c->leb_size - alen, alen - len);
+			memset(p, 0xff, alen - len);
+			err = ubi_leb_change(c->ubi, lnum++, buf, alen,
+					     UBI_SHORTTERM);
+			if (err)
+				goto out;
+			p = buf;
+			len = 0;
+		}
+
+		c->lsave_lnum = lnum;
+		c->lsave_offs = len;
+
+		for (i = 0; i < c->lsave_cnt && i < *main_lebs; i++)
+			lsave[i] = c->main_first + i;
+		for (; i < c->lsave_cnt; i++)
+			lsave[i] = c->main_first;
+
+		ubifs_pack_lsave(c, p, lsave);
+		p += c->lsave_sz;
+		len += c->lsave_sz;
+	}
+
+	/* Need to add LPT's own LEB properties table */
+	if (len + c->ltab_sz > c->leb_size) {
+		alen = ALIGN(len, c->min_io_size);
+		set_ltab(c, lnum, c->leb_size - alen, alen - len);
+		memset(p, 0xff, alen - len);
+		err = ubi_leb_change(c->ubi, lnum++, buf, alen, UBI_SHORTTERM);
+		if (err)
+			goto out;
+		p = buf;
+		len = 0;
+	}
+
+	c->ltab_lnum = lnum;
+	c->ltab_offs = len;
+
+	/* Update ltab before packing it */
+	len += c->ltab_sz;
+	alen = ALIGN(len, c->min_io_size);
+	set_ltab(c, lnum, c->leb_size - alen, alen - len);
+
+	ubifs_pack_ltab(c, p, ltab);
+	p += c->ltab_sz;
+
+	/* Write remaining buffer */
+	memset(p, 0xff, alen - len);
+	err = ubi_leb_change(c->ubi, lnum, buf, alen, UBI_SHORTTERM);
+	if (err)
+		goto out;
+
+	c->nhead_lnum = lnum;
+	c->nhead_offs = ALIGN(len, c->min_io_size);
+
+	dbg_lp("space_bits %d", c->space_bits);
+	dbg_lp("lpt_lnum_bits %d", c->lpt_lnum_bits);
+	dbg_lp("lpt_offs_bits %d", c->lpt_offs_bits);
+	dbg_lp("lpt_spc_bits %d", c->lpt_spc_bits);
+	dbg_lp("pcnt_bits %d", c->pcnt_bits);
+	dbg_lp("lnum_bits %d", c->lnum_bits);
+	dbg_lp("pnode_sz %d", c->pnode_sz);
+	dbg_lp("nnode_sz %d", c->nnode_sz);
+	dbg_lp("ltab_sz %d", c->ltab_sz);
+	dbg_lp("lsave_sz %d", c->lsave_sz);
+	dbg_lp("lsave_cnt %d", c->lsave_cnt);
+	dbg_lp("lpt_hght %d", c->lpt_hght);
+	dbg_lp("big_lpt %d", c->big_lpt);
+	dbg_lp("LPT root is at %d:%d", c->lpt_lnum, c->lpt_offs);
+	dbg_lp("LPT head is at %d:%d", c->nhead_lnum, c->nhead_offs);
+	dbg_lp("LPT ltab is at %d:%d", c->ltab_lnum, c->ltab_offs);
+	if (c->big_lpt)
+		dbg_lp("LPT lsave is at %d:%d", c->lsave_lnum, c->lsave_offs);
+out:
+	c->ltab = NULL;
+	kfree(lsave);
+	vfree(ltab);
+	vfree(buf);
+	kfree(nnode);
+	kfree(pnode);
+	return err;
+}
+
+/**
+ * update_cats - add LEB properties of a pnode to LEB category lists and heaps.
+ * @c: UBIFS file-system description object
+ * @pnode: pnode
+ *
+ * When a pnode is loaded into memory, the LEB properties it contains are added,
+ * by this function, to the LEB category lists and heaps.
+ */
+static void update_cats(struct ubifs_info *c, struct ubifs_pnode *pnode)
+{
+	int i;
+
+	for (i = 0; i < UBIFS_LPT_FANOUT; i++) {
+		int cat = pnode->lprops[i].flags & LPROPS_CAT_MASK;
+		int lnum = pnode->lprops[i].lnum;
+
+		if (!lnum)
+			return;
+		ubifs_add_to_cat(c, &pnode->lprops[i], cat);
+	}
+}
+
+/**
+ * replace_cats - add LEB properties of a pnode to LEB category lists and heaps.
+ * @c: UBIFS file-system description object
+ * @old_pnode: pnode copied
+ * @new_pnode: pnode copy
+ *
+ * During commit it is sometimes necessary to copy a pnode
+ * (see dirty_cow_pnode).  When that happens, references in
+ * category lists and heaps must be replaced.  This function does that.
+ */
+static void replace_cats(struct ubifs_info *c, struct ubifs_pnode *old_pnode,
+			 struct ubifs_pnode *new_pnode)
+{
+	int i;
+
+	for (i = 0; i < UBIFS_LPT_FANOUT; i++) {
+		if (!new_pnode->lprops[i].lnum)
+			return;
+		ubifs_replace_cat(c, &old_pnode->lprops[i],
+				  &new_pnode->lprops[i]);
+	}
+}
+
+/**
+ * check_lpt_crc - check LPT node crc is correct.
+ * @c: UBIFS file-system description object
+ * @buf: buffer containing node
+ * @len: length of node
+ *
+ * This function returns %0 on success and a negative error code on failure.
+ */
+static int check_lpt_crc(void *buf, int len)
+{
+	int pos = 0;
+	uint8_t *addr = buf;
+	uint16_t crc, calc_crc;
+
+	crc = ubifs_unpack_bits(&addr, &pos, UBIFS_LPT_CRC_BITS);
+	calc_crc = crc16(-1, buf + UBIFS_LPT_CRC_BYTES,
+			 len - UBIFS_LPT_CRC_BYTES);
+	if (crc != calc_crc) {
+		ubifs_err("invalid crc in LPT node: crc %hx calc %hx", crc,
+			  calc_crc);
+		dbg_dump_stack();
+		return -EINVAL;
+	}
+	return 0;
+}
+
+/**
+ * check_lpt_type - check LPT node type is correct.
+ * @c: UBIFS file-system description object
+ * @addr: address of type bit field is passed and returned updated here
+ * @pos: position of type bit field is passed and returned updated here
+ * @type: expected type
+ *
+ * This function returns %0 on success and a negative error code on failure.
+ */
+static int check_lpt_type(uint8_t **addr, int *pos, int type)
+{
+	int node_type;
+
+	node_type = ubifs_unpack_bits(addr, pos, UBIFS_LPT_TYPE_BITS);
+	if (node_type != type) {
+		ubifs_err("invalid type (%d) in LPT node type %d", node_type,
+			  type);
+		dbg_dump_stack();
+		return -EINVAL;
+	}
+	return 0;
+}
+
+/**
+ * unpack_pnode - unpack a pnode.
+ * @c: UBIFS file-system description object
+ * @buf: buffer containing packed pnode to unpack
+ * @pnode: pnode structure to fill
+ *
+ * This function returns %0 on success and a negative error code on failure.
+ */
+static int unpack_pnode(struct ubifs_info *c, void *buf,
+			struct ubifs_pnode *pnode)
+{
+	uint8_t *addr = buf + UBIFS_LPT_CRC_BYTES;
+	int i, pos = 0, err;
+
+	err = check_lpt_type(&addr, &pos, UBIFS_LPT_PNODE);
+	if (err)
+		return err;
+	if (c->big_lpt)
+		pnode->num = ubifs_unpack_bits(&addr, &pos, c->pcnt_bits);
+	for (i = 0; i < UBIFS_LPT_FANOUT; i++) {
+		struct ubifs_lprops * const lprops = &pnode->lprops[i];
+
+		lprops->free = ubifs_unpack_bits(&addr, &pos, c->space_bits);
+		lprops->free <<= 3;
+		lprops->dirty = ubifs_unpack_bits(&addr, &pos, c->space_bits);
+		lprops->dirty <<= 3;
+
+		if (ubifs_unpack_bits(&addr, &pos, 1))
+			lprops->flags = LPROPS_INDEX;
+		else
+			lprops->flags = 0;
+		lprops->flags |= ubifs_categorize_lprops(c, lprops);
+	}
+	err = check_lpt_crc(buf, c->pnode_sz);
+	return err;
+}
+
+/**
+ * unpack_nnode - unpack a nnode.
+ * @c: UBIFS file-system description object
+ * @buf: buffer containing packed nnode to unpack
+ * @nnode: nnode structure to fill
+ *
+ * This function returns %0 on success and a negative error code on failure.
+ */
+static int unpack_nnode(struct ubifs_info *c, void *buf,
+			struct ubifs_nnode *nnode)
+{
+	uint8_t *addr = buf + UBIFS_LPT_CRC_BYTES;
+	int i, pos = 0, err;
+
+	err = check_lpt_type(&addr, &pos, UBIFS_LPT_NNODE);
+	if (err)
+		return err;
+	if (c->big_lpt)
+		nnode->num = ubifs_unpack_bits(&addr, &pos, c->pcnt_bits);
+	for (i = 0; i < UBIFS_LPT_FANOUT; i++) {
+		int lnum;
+
+		lnum = ubifs_unpack_bits(&addr, &pos, c->lpt_lnum_bits) +
+		       c->lpt_first;
+		if (lnum == c->lpt_last + 1)
+			lnum = 0;
+		nnode->nbranch[i].lnum = lnum;
+		nnode->nbranch[i].offs = ubifs_unpack_bits(&addr, &pos,
+						     c->lpt_offs_bits);
+	}
+	err = check_lpt_crc(buf, c->nnode_sz);
+	return err;
+}
+
+/**
+ * unpack_ltab - unpack the LPT's own lprops table.
+ * @c: UBIFS file-system description object
+ * @buf: buffer from which to unpack
+ *
+ * This function returns %0 on success and a negative error code on failure.
+ */
+static int unpack_ltab(struct ubifs_info *c, void *buf)
+{
+	uint8_t *addr = buf + UBIFS_LPT_CRC_BYTES;
+	int i, pos = 0, err;
+
+	err = check_lpt_type(&addr, &pos, UBIFS_LPT_LTAB);
+	if (err)
+		return err;
+	for (i = 0; i < c->lpt_lebs; i++) {
+		int free = ubifs_unpack_bits(&addr, &pos, c->lpt_spc_bits);
+		int dirty = ubifs_unpack_bits(&addr, &pos, c->lpt_spc_bits);
+
+		if (free < 0 || free > c->leb_size || dirty < 0 ||
+		    dirty > c->leb_size || free + dirty > c->leb_size)
+			return -EINVAL;
+
+		c->ltab[i].free = free;
+		c->ltab[i].dirty = dirty;
+		c->ltab[i].tgc = 0;
+		c->ltab[i].cmt = 0;
+	}
+	err = check_lpt_crc(buf, c->ltab_sz);
+	return err;
+}
+
+/**
+ * unpack_lsave - unpack the LPT's save table.
+ * @c: UBIFS file-system description object
+ * @buf: buffer from which to unpack
+ *
+ * This function returns %0 on success and a negative error code on failure.
+ */
+static int unpack_lsave(struct ubifs_info *c, void *buf)
+{
+	uint8_t *addr = buf + UBIFS_LPT_CRC_BYTES;
+	int i, pos = 0, err;
+
+	err = check_lpt_type(&addr, &pos, UBIFS_LPT_LSAVE);
+	if (err)
+		return err;
+	for (i = 0; i < c->lsave_cnt; i++) {
+		int lnum = ubifs_unpack_bits(&addr, &pos, c->lnum_bits);
+
+		if (lnum < c->main_first || lnum >= c->leb_cnt)
+			return -EINVAL;
+		c->lsave[i] = lnum;
+	}
+	err = check_lpt_crc(buf, c->lsave_sz);
+	return err;
+}
+
+/**
+ * validate_nnode - validate a nnode.
+ * @c: UBIFS file-system description object
+ * @nnode: nnode to validate
+ * @parent: parent nnode (or NULL for the root nnode)
+ * @iip: index in parent
+ *
+ * This function returns %0 on success and a negative error code on failure.
+ */
+static int validate_nnode(struct ubifs_info *c, struct ubifs_nnode *nnode,
+			  struct ubifs_nnode *parent, int iip)
+{
+	int i, lvl, max_offs;
+
+	if (c->big_lpt) {
+		int num = calc_nnode_num_from_parent(c, parent, iip);
+
+		if (nnode->num != num)
+			return -EINVAL;
+	}
+	lvl = parent ? parent->level - 1 : c->lpt_hght;
+	if (lvl < 1)
+		return -EINVAL;
+	if (lvl == 1)
+		max_offs = c->leb_size - c->pnode_sz;
+	else
+		max_offs = c->leb_size - c->nnode_sz;
+	for (i = 0; i < UBIFS_LPT_FANOUT; i++) {
+		int lnum = nnode->nbranch[i].lnum;
+		int offs = nnode->nbranch[i].offs;
+
+		if (lnum == 0) {
+			if (offs != 0)
+				return -EINVAL;
+			continue;
+		}
+		if (lnum < c->lpt_first || lnum > c->lpt_last)
+			return -EINVAL;
+		if (offs < 0 || offs > max_offs)
+			return -EINVAL;
+	}
+	return 0;
+}
+
+/**
+ * validate_pnode - validate a pnode.
+ * @c: UBIFS file-system description object
+ * @pnode: pnode to validate
+ * @parent: parent nnode
+ * @iip: index in parent
+ *
+ * This function returns %0 on success and a negative error code on failure.
+ */
+static int validate_pnode(struct ubifs_info *c, struct ubifs_pnode *pnode,
+			  struct ubifs_nnode *parent, int iip)
+{
+	int i;
+
+	if (c->big_lpt) {
+		int num = calc_pnode_num_from_parent(c, parent, iip);
+
+		if (pnode->num != num)
+			return -EINVAL;
+	}
+	for (i = 0; i < UBIFS_LPT_FANOUT; i++) {
+		int free = pnode->lprops[i].free;
+		int dirty = pnode->lprops[i].dirty;
+
+		if (free < 0 || free > c->leb_size || free % c->min_io_size ||
+		    (free & 7))
+			return -EINVAL;
+		if (dirty < 0 || dirty > c->leb_size || (dirty & 7))
+			return -EINVAL;
+		if (dirty + free > c->leb_size)
+			return -EINVAL;
+	}
+	return 0;
+}
+
+/**
+ * set_pnode_lnum - set LEB numbers on a pnode.
+ * @c: UBIFS file-system description object
+ * @pnode: pnode to update
+ *
+ * This function calculates the LEB numbers for the LEB properties it contains
+ * based on the pnode number.
+ */
+static void set_pnode_lnum(struct ubifs_info *c, struct ubifs_pnode *pnode)
+{
+	int i, lnum;
+
+	lnum = (pnode->num << UBIFS_LPT_FANOUT_SHIFT) + c->main_first;
+	for (i = 0; i < UBIFS_LPT_FANOUT; i++) {
+		if (lnum >= c->leb_cnt)
+			return;
+		pnode->lprops[i].lnum = lnum++;
+	}
+}
+
+/**
+ * ubifs_read_nnode - read a nnode from flash and link it to the tree in memory.
+ * @c: UBIFS file-system description object
+ * @parent: parent nnode (or NULL for the root)
+ * @iip: index in parent
+ *
+ * This function returns %0 on success and a negative error code on failure.
+ */
+int ubifs_read_nnode(struct ubifs_info *c, struct ubifs_nnode *parent, int iip)
+{
+	struct ubifs_nbranch *branch = NULL;
+	struct ubifs_nnode *nnode = NULL;
+	void *buf = c->lpt_nod_buf;
+	int err, lnum, offs;
+
+	if (parent) {
+		branch = &parent->nbranch[iip];
+		lnum = branch->lnum;
+		offs = branch->offs;
+	} else {
+		lnum = c->lpt_lnum;
+		offs = c->lpt_offs;
+	}
+	nnode = kzalloc(sizeof(struct ubifs_nnode), GFP_NOFS);
+	if (!nnode) {
+		err = -ENOMEM;
+		goto out;
+	}
+	if (lnum == 0) {
+		/*
+		 * This nnode was not written which just means that the LEB
+		 * properties in the subtree below it describe empty LEBs. We
+		 * make the nnode as though we had read it, which in fact means
+		 * doing almost nothing.
+		 */
+		if (c->big_lpt)
+			nnode->num = calc_nnode_num_from_parent(c, parent, iip);
+	} else {
+		err = ubi_read(c->ubi, lnum, buf, offs, c->nnode_sz);
+		if (err)
+			goto out;
+		err = unpack_nnode(c, buf, nnode);
+		if (err)
+			goto out;
+	}
+	err = validate_nnode(c, nnode, parent, iip);
+	if (err)
+		goto out;
+	if (!c->big_lpt)
+		nnode->num = calc_nnode_num_from_parent(c, parent, iip);
+	if (parent) {
+		branch->nnode = nnode;
+		nnode->level = parent->level - 1;
+	} else {
+		c->nroot = nnode;
+		nnode->level = c->lpt_hght;
+	}
+	nnode->parent = parent;
+	nnode->iip = iip;
+	return 0;
+
+out:
+	ubifs_err("error %d reading nnode at %d:%d", err, lnum, offs);
+	kfree(nnode);
+	return err;
+}
+
+/**
+ * read_pnode - read a pnode from flash and link it to the tree in memory.
+ * @c: UBIFS file-system description object
+ * @parent: parent nnode
+ * @iip: index in parent
+ *
+ * This function returns %0 on success and a negative error code on failure.
+ */
+static int read_pnode(struct ubifs_info *c, struct ubifs_nnode *parent, int iip)
+{
+	struct ubifs_nbranch *branch;
+	struct ubifs_pnode *pnode = NULL;
+	void *buf = c->lpt_nod_buf;
+	int err, lnum, offs;
+
+	branch = &parent->nbranch[iip];
+	lnum = branch->lnum;
+	offs = branch->offs;
+	pnode = kzalloc(sizeof(struct ubifs_pnode), GFP_NOFS);
+	if (!pnode) {
+		err = -ENOMEM;
+		goto out;
+	}
+	if (lnum == 0) {
+		/*
+		 * This pnode was not written which just means that the LEB
+		 * properties in it describe empty LEBs. We make the pnode as
+		 * though we had read it.
+		 */
+		int i;
+
+		if (c->big_lpt)
+			pnode->num = calc_pnode_num_from_parent(c, parent, iip);
+		for (i = 0; i < UBIFS_LPT_FANOUT; i++) {
+			struct ubifs_lprops * const lprops = &pnode->lprops[i];
+
+			lprops->free = c->leb_size;
+			lprops->flags = ubifs_categorize_lprops(c, lprops);
+		}
+	} else {
+		err = ubi_read(c->ubi, lnum, buf, offs, c->pnode_sz);
+		if (err)
+			goto out;
+		err = unpack_pnode(c, buf, pnode);
+		if (err)
+			goto out;
+	}
+	err = validate_pnode(c, pnode, parent, iip);
+	if (err)
+		goto out;
+	if (!c->big_lpt)
+		pnode->num = calc_pnode_num_from_parent(c, parent, iip);
+	branch->pnode = pnode;
+	pnode->parent = parent;
+	pnode->iip = iip;
+	set_pnode_lnum(c, pnode);
+	c->pnodes_have += 1;
+	return 0;
+
+out:
+	ubifs_err("error %d reading pnode at %d:%d", err, lnum, offs);
+	dbg_dump_pnode(c, pnode, parent, iip);
+	dbg_msg("calc num: %d", calc_pnode_num_from_parent(c, parent, iip));
+	kfree(pnode);
+	return err;
+}
+
+/**
+ * read_ltab - read LPT's own lprops table.
+ * @c: UBIFS file-system description object
+ *
+ * This function returns %0 on success and a negative error code on failure.
+ */
+static int read_ltab(struct ubifs_info *c)
+{
+	int err;
+	void *buf;
+
+	buf = vmalloc(c->ltab_sz);
+	if (!buf)
+		return -ENOMEM;
+	err = ubi_read(c->ubi, c->ltab_lnum, buf, c->ltab_offs, c->ltab_sz);
+	if (err)
+		goto out;
+	err = unpack_ltab(c, buf);
+out:
+	vfree(buf);
+	return err;
+}
+
+/**
+ * read_lsave - read LPT's save table.
+ * @c: UBIFS file-system description object
+ *
+ * This function returns %0 on success and a negative error code on failure.
+ */
+static int read_lsave(struct ubifs_info *c)
+{
+	int err, i;
+	void *buf;
+
+	buf = vmalloc(c->lsave_sz);
+	if (!buf)
+		return -ENOMEM;
+	err = ubi_read(c->ubi, c->lsave_lnum, buf, c->lsave_offs, c->lsave_sz);
+	if (err)
+		goto out;
+	err = unpack_lsave(c, buf);
+	if (err)
+		goto out;
+	for (i = 0; i < c->lsave_cnt; i++) {
+		int lnum = c->lsave[i];
+
+		/*
+		 * Due to automatic resizing, the values in the lsave table
+		 * could be beyond the volume size - just ignore them.
+		 */
+		if (lnum >= c->leb_cnt)
+			continue;
+		ubifs_lpt_lookup(c, lnum);
+	}
+out:
+	vfree(buf);
+	return err;
+}
+
+/**
+ * ubifs_get_nnode - get a nnode.
+ * @c: UBIFS file-system description object
+ * @parent: parent nnode (or NULL for the root)
+ * @iip: index in parent
+ *
+ * This function returns a pointer to the nnode on success or a negative error
+ * code on failure.
+ */
+struct ubifs_nnode *ubifs_get_nnode(struct ubifs_info *c,
+				    struct ubifs_nnode *parent, int iip)
+{
+	struct ubifs_nbranch *branch;
+	struct ubifs_nnode *nnode;
+	int err;
+
+	branch = &parent->nbranch[iip];
+	nnode = branch->nnode;
+	if (nnode)
+		return nnode;
+	err = ubifs_read_nnode(c, parent, iip);
+	if (err)
+		return ERR_PTR(err);
+	return branch->nnode;
+}
+
+/**
+ * ubifs_get_pnode - get a pnode.
+ * @c: UBIFS file-system description object
+ * @parent: parent nnode
+ * @iip: index in parent
+ *
+ * This function returns a pointer to the pnode on success or a negative error
+ * code on failure.
+ */
+struct ubifs_pnode *ubifs_get_pnode(struct ubifs_info *c,
+				    struct ubifs_nnode *parent, int iip)
+{
+	struct ubifs_nbranch *branch;
+	struct ubifs_pnode *pnode;
+	int err;
+
+	branch = &parent->nbranch[iip];
+	pnode = branch->pnode;
+	if (pnode)
+		return pnode;
+	err = read_pnode(c, parent, iip);
+	if (err)
+		return ERR_PTR(err);
+	update_cats(c, branch->pnode);
+	return branch->pnode;
+}
+
+/**
+ * ubifs_lpt_lookup - lookup LEB properties in the LPT.
+ * @c: UBIFS file-system description object
+ * @lnum: LEB number to lookup
+ *
+ * This function returns a pointer to the LEB properties on success or a
+ * negative error code on failure.
+ */
+struct ubifs_lprops *ubifs_lpt_lookup(struct ubifs_info *c, int lnum)
+{
+	int err, i, h, iip, shft;
+	struct ubifs_nnode *nnode;
+	struct ubifs_pnode *pnode;
+
+	if (!c->nroot) {
+		err = ubifs_read_nnode(c, NULL, 0);
+		if (err)
+			return ERR_PTR(err);
+	}
+	nnode = c->nroot;
+	i = lnum - c->main_first;
+	shft = c->lpt_hght * UBIFS_LPT_FANOUT_SHIFT;
+	for (h = 1; h < c->lpt_hght; h++) {
+		iip = ((i >> shft) & (UBIFS_LPT_FANOUT - 1));
+		shft -= UBIFS_LPT_FANOUT_SHIFT;
+		nnode = ubifs_get_nnode(c, nnode, iip);
+		if (IS_ERR(nnode))
+			return ERR_PTR(PTR_ERR(nnode));
+	}
+	iip = ((i >> shft) & (UBIFS_LPT_FANOUT - 1));
+	shft -= UBIFS_LPT_FANOUT_SHIFT;
+	pnode = ubifs_get_pnode(c, nnode, iip);
+	if (IS_ERR(pnode))
+		return ERR_PTR(PTR_ERR(pnode));
+	iip = (i & (UBIFS_LPT_FANOUT - 1));
+	dbg_lp("LEB %d, free %d, dirty %d, flags %d", lnum,
+	       pnode->lprops[iip].free, pnode->lprops[iip].dirty,
+	       pnode->lprops[iip].flags);
+	return &pnode->lprops[iip];
+}
+
+/**
+ * dirty_cow_nnode - ensure a nnode is not being committed.
+ * @c: UBIFS file-system description object
+ * @nnode: nnode to check
+ *
+ * Returns dirtied nnode on success or negative error code on failure.
+ */
+static struct ubifs_nnode *dirty_cow_nnode(struct ubifs_info *c,
+					   struct ubifs_nnode *nnode)
+{
+	struct ubifs_nnode *n;
+	int i;
+
+	if (!test_bit(COW_CNODE, &nnode->flags)) {
+		/* nnode is not being committed */
+		if (!test_and_set_bit(DIRTY_CNODE, &nnode->flags)) {
+			c->dirty_nn_cnt += 1;
+			ubifs_add_nnode_dirt(c, nnode);
+		}
+		return nnode;
+	}
+
+	/* nnode is being committed, so copy it */
+	n = kmalloc(sizeof(struct ubifs_nnode), GFP_NOFS);
+	if (unlikely(!n))
+		return ERR_PTR(-ENOMEM);
+
+	memcpy(n, nnode, sizeof(struct ubifs_nnode));
+	n->cnext = NULL;
+	__set_bit(DIRTY_CNODE, &n->flags);
+	__clear_bit(COW_CNODE, &n->flags);
+
+	/* The children now have new parent */
+	for (i = 0; i < UBIFS_LPT_FANOUT; i++) {
+		struct ubifs_nbranch *branch = &n->nbranch[i];
+
+		if (branch->cnode)
+			branch->cnode->parent = n;
+	}
+
+	ubifs_assert(!test_bit(OBSOLETE_CNODE, &nnode->flags));
+	__set_bit(OBSOLETE_CNODE, &nnode->flags);
+
+	c->dirty_nn_cnt += 1;
+	ubifs_add_nnode_dirt(c, nnode);
+	if (nnode->parent)
+		nnode->parent->nbranch[n->iip].nnode = n;
+	else
+		c->nroot = n;
+	return n;
+}
+
+/**
+ * dirty_cow_pnode - ensure a pnode is not being committed.
+ * @c: UBIFS file-system description object
+ * @pnode: pnode to check
+ *
+ * Returns dirtied pnode on success or negative error code on failure.
+ */
+static struct ubifs_pnode *dirty_cow_pnode(struct ubifs_info *c,
+					   struct ubifs_pnode *pnode)
+{
+	struct ubifs_pnode *p;
+
+	if (!test_bit(COW_CNODE, &pnode->flags)) {
+		/* pnode is not being committed */
+		if (!test_and_set_bit(DIRTY_CNODE, &pnode->flags)) {
+			c->dirty_pn_cnt += 1;
+			add_pnode_dirt(c, pnode);
+		}
+		return pnode;
+	}
+
+	/* pnode is being committed, so copy it */
+	p = kmalloc(sizeof(struct ubifs_pnode), GFP_NOFS);
+	if (unlikely(!p))
+		return ERR_PTR(-ENOMEM);
+
+	memcpy(p, pnode, sizeof(struct ubifs_pnode));
+	p->cnext = NULL;
+	__set_bit(DIRTY_CNODE, &p->flags);
+	__clear_bit(COW_CNODE, &p->flags);
+	replace_cats(c, pnode, p);
+
+	ubifs_assert(!test_bit(OBSOLETE_CNODE, &pnode->flags));
+	__set_bit(OBSOLETE_CNODE, &pnode->flags);
+
+	c->dirty_pn_cnt += 1;
+	add_pnode_dirt(c, pnode);
+	pnode->parent->nbranch[p->iip].pnode = p;
+	return p;
+}
+
+/**
+ * ubifs_lpt_lookup_dirty - lookup LEB properties in the LPT.
+ * @c: UBIFS file-system description object
+ * @lnum: LEB number to lookup
+ *
+ * This function returns a pointer to the LEB properties on success or a
+ * negative error code on failure.
+ */
+struct ubifs_lprops *ubifs_lpt_lookup_dirty(struct ubifs_info *c, int lnum)
+{
+	int err, i, h, iip, shft;
+	struct ubifs_nnode *nnode;
+	struct ubifs_pnode *pnode;
+
+	if (!c->nroot) {
+		err = ubifs_read_nnode(c, NULL, 0);
+		if (err)
+			return ERR_PTR(err);
+	}
+	nnode = c->nroot;
+	nnode = dirty_cow_nnode(c, nnode);
+	if (IS_ERR(nnode))
+		return ERR_PTR(PTR_ERR(nnode));
+	i = lnum - c->main_first;
+	shft = c->lpt_hght * UBIFS_LPT_FANOUT_SHIFT;
+	for (h = 1; h < c->lpt_hght; h++) {
+		iip = ((i >> shft) & (UBIFS_LPT_FANOUT - 1));
+		shft -= UBIFS_LPT_FANOUT_SHIFT;
+		nnode = ubifs_get_nnode(c, nnode, iip);
+		if (IS_ERR(nnode))
+			return ERR_PTR(PTR_ERR(nnode));
+		nnode = dirty_cow_nnode(c, nnode);
+		if (IS_ERR(nnode))
+			return ERR_PTR(PTR_ERR(nnode));
+	}
+	iip = ((i >> shft) & (UBIFS_LPT_FANOUT - 1));
+	shft -= UBIFS_LPT_FANOUT_SHIFT;
+	pnode = ubifs_get_pnode(c, nnode, iip);
+	if (IS_ERR(pnode))
+		return ERR_PTR(PTR_ERR(pnode));
+	pnode = dirty_cow_pnode(c, pnode);
+	if (IS_ERR(pnode))
+		return ERR_PTR(PTR_ERR(pnode));
+	iip = (i & (UBIFS_LPT_FANOUT - 1));
+	dbg_lp("LEB %d, free %d, dirty %d, flags %d", lnum,
+	       pnode->lprops[iip].free, pnode->lprops[iip].dirty,
+	       pnode->lprops[iip].flags);
+	ubifs_assert(test_bit(DIRTY_CNODE, &pnode->flags));
+	return &pnode->lprops[iip];
+}
+
+/**
+ * lpt_init_rd - initialize the LPT for reading.
+ * @c: UBIFS file-system description object
+ *
+ * This function returns %0 on success and a negative error code on failure.
+ */
+static int lpt_init_rd(struct ubifs_info *c)
+{
+	int err, i;
+
+	c->ltab = vmalloc(sizeof(struct ubifs_lpt_lprops) * c->lpt_lebs);
+	if (!c->ltab)
+		return -ENOMEM;
+
+	i = max_t(int, c->nnode_sz, c->pnode_sz);
+	c->lpt_nod_buf = kmalloc(i, GFP_KERNEL);
+	if (!c->lpt_nod_buf)
+		return -ENOMEM;
+
+	for (i = 0; i < LPROPS_HEAP_CNT; i++) {
+		c->lpt_heap[i].arr = kmalloc(sizeof(void *) * LPT_HEAP_SZ,
+					     GFP_KERNEL);
+		if (!c->lpt_heap[i].arr)
+			return -ENOMEM;
+		c->lpt_heap[i].cnt = 0;
+		c->lpt_heap[i].max_cnt = LPT_HEAP_SZ;
+	}
+
+	c->dirty_idx.arr = kmalloc(sizeof(void *) * LPT_HEAP_SZ, GFP_KERNEL);
+	if (!c->dirty_idx.arr)
+		return -ENOMEM;
+	c->dirty_idx.cnt = 0;
+	c->dirty_idx.max_cnt = LPT_HEAP_SZ;
+
+	err = read_ltab(c);
+	if (err)
+		return err;
+
+	dbg_lp("space_bits %d", c->space_bits);
+	dbg_lp("lpt_lnum_bits %d", c->lpt_lnum_bits);
+	dbg_lp("lpt_offs_bits %d", c->lpt_offs_bits);
+	dbg_lp("lpt_spc_bits %d", c->lpt_spc_bits);
+	dbg_lp("pcnt_bits %d", c->pcnt_bits);
+	dbg_lp("lnum_bits %d", c->lnum_bits);
+	dbg_lp("pnode_sz %d", c->pnode_sz);
+	dbg_lp("nnode_sz %d", c->nnode_sz);
+	dbg_lp("ltab_sz %d", c->ltab_sz);
+	dbg_lp("lsave_sz %d", c->lsave_sz);
+	dbg_lp("lsave_cnt %d", c->lsave_cnt);
+	dbg_lp("lpt_hght %d", c->lpt_hght);
+	dbg_lp("big_lpt %d", c->big_lpt);
+	dbg_lp("LPT root is at %d:%d", c->lpt_lnum, c->lpt_offs);
+	dbg_lp("LPT head is at %d:%d", c->nhead_lnum, c->nhead_offs);
+	dbg_lp("LPT ltab is at %d:%d", c->ltab_lnum, c->ltab_offs);
+	if (c->big_lpt)
+		dbg_lp("LPT lsave is at %d:%d", c->lsave_lnum, c->lsave_offs);
+
+	return 0;
+}
+
+/**
+ * lpt_init_wr - initialize the LPT for writing.
+ * @c: UBIFS file-system description object
+ *
+ * 'lpt_init_rd()' must have been called already.
+ *
+ * This function returns %0 on success and a negative error code on failure.
+ */
+static int lpt_init_wr(struct ubifs_info *c)
+{
+	int err, i;
+
+	c->ltab_cmt = vmalloc(sizeof(struct ubifs_lpt_lprops) * c->lpt_lebs);
+	if (!c->ltab_cmt)
+		return -ENOMEM;
+
+	c->lpt_buf = vmalloc(c->leb_size);
+	if (!c->lpt_buf)
+		return -ENOMEM;
+
+	if (c->big_lpt) {
+		c->lsave = kmalloc(sizeof(int) * c->lsave_cnt, GFP_NOFS);
+		if (!c->lsave)
+			return -ENOMEM;
+		err = read_lsave(c);
+		if (err)
+			return err;
+	}
+
+	for (i = 0; i < c->lpt_lebs; i++)
+		if (c->ltab[i].free == c->leb_size) {
+			err = ubifs_leb_unmap(c, i + c->lpt_first);
+			if (err)
+				return err;
+		}
+
+	return 0;
+}
+
+/**
+ * ubifs_lpt_init - initialize the LPT.
+ * @c: UBIFS file-system description object
+ * @rd: whether to initialize lpt for reading
+ * @wr: whether to initialize lpt for writing
+ *
+ * For mounting 'rw', @rd and @wr are both true. For mounting 'ro', @rd is true
+ * and @wr is false. For mounting from 'ro' to 'rw', @rd is false and @wr is
+ * true.
+ *
+ * This function returns %0 on success and a negative error code on failure.
+ */
+int ubifs_lpt_init(struct ubifs_info *c, int rd, int wr)
+{
+	int err;
+
+	if (rd) {
+		err = lpt_init_rd(c);
+		if (err)
+			return err;
+	}
+
+	if (wr) {
+		err = lpt_init_wr(c);
+		if (err)
+			return err;
+	}
+
+	return 0;
+}
+
+/**
+ * struct lpt_scan_node - somewhere to put nodes while we scan LPT.
+ * @nnode: where to keep a nnode
+ * @pnode: where to keep a pnode
+ * @cnode: where to keep a cnode
+ * @in_tree: is the node in the tree in memory
+ * @ptr.nnode: pointer to the nnode (if it is an nnode) which may be here or in
+ * the tree
+ * @ptr.pnode: ditto for pnode
+ * @ptr.cnode: ditto for cnode
+ */
+struct lpt_scan_node {
+	union {
+		struct ubifs_nnode nnode;
+		struct ubifs_pnode pnode;
+		struct ubifs_cnode cnode;
+	};
+	int in_tree;
+	union {
+		struct ubifs_nnode *nnode;
+		struct ubifs_pnode *pnode;
+		struct ubifs_cnode *cnode;
+	} ptr;
+};
+
+/**
+ * scan_get_nnode - for the scan, get a nnode from either the tree or flash.
+ * @c: the UBIFS file-system description object
+ * @path: where to put the nnode
+ * @parent: parent of the nnode
+ * @iip: index in parent of the nnode
+ *
+ * This function returns a pointer to the nnode on success or a negative error
+ * code on failure.
+ */
+static struct ubifs_nnode *scan_get_nnode(struct ubifs_info *c,
+					  struct lpt_scan_node *path,
+					  struct ubifs_nnode *parent, int iip)
+{
+	struct ubifs_nbranch *branch;
+	struct ubifs_nnode *nnode;
+	void *buf = c->lpt_nod_buf;
+	int err;
+
+	branch = &parent->nbranch[iip];
+	nnode = branch->nnode;
+	if (nnode) {
+		path->in_tree = 1;
+		path->ptr.nnode = nnode;
+		return nnode;
+	}
+	nnode = &path->nnode;
+	path->in_tree = 0;
+	path->ptr.nnode = nnode;
+	memset(nnode, 0, sizeof(struct ubifs_nnode));
+	if (branch->lnum == 0) {
+		/*
+		 * This nnode was not written which just means that the LEB
+		 * properties in the subtree below it describe empty LEBs. We
+		 * make the nnode as though we had read it, which in fact means
+		 * doing almost nothing.
+		 */
+		if (c->big_lpt)
+			nnode->num = calc_nnode_num_from_parent(c, parent, iip);
+	} else {
+		err = ubi_read(c->ubi, branch->lnum, buf, branch->offs,
+			       c->nnode_sz);
+		if (err)
+			return ERR_PTR(err);
+		err = unpack_nnode(c, buf, nnode);
+		if (err)
+			return ERR_PTR(err);
+	}
+	err = validate_nnode(c, nnode, parent, iip);
+	if (err)
+		return ERR_PTR(err);
+	if (!c->big_lpt)
+		nnode->num = calc_nnode_num_from_parent(c, parent, iip);
+	nnode->level = parent->level - 1;
+	nnode->parent = parent;
+	nnode->iip = iip;
+	return nnode;
+}
+
+/**
+ * scan_get_pnode - for the scan, get a pnode from either the tree or flash.
+ * @c: the UBIFS file-system description object
+ * @path: where to put the pnode
+ * @parent: parent of the pnode
+ * @iip: index in parent of the pnode
+ *
+ * This function returns a pointer to the pnode on success or a negative error
+ * code on failure.
+ */
+static struct ubifs_pnode *scan_get_pnode(struct ubifs_info *c,
+					  struct lpt_scan_node *path,
+					  struct ubifs_nnode *parent, int iip)
+{
+	struct ubifs_nbranch *branch;
+	struct ubifs_pnode *pnode;
+	void *buf = c->lpt_nod_buf;
+	int err;
+
+	branch = &parent->nbranch[iip];
+	pnode = branch->pnode;
+	if (pnode) {
+		path->in_tree = 1;
+		path->ptr.pnode = pnode;
+		return pnode;
+	}
+	pnode = &path->pnode;
+	path->in_tree = 0;
+	path->ptr.pnode = pnode;
+	memset(pnode, 0, sizeof(struct ubifs_pnode));
+	if (branch->lnum == 0) {
+		/*
+		 * This pnode was not written which just means that the LEB
+		 * properties in it describe empty LEBs. We make the pnode as
+		 * though we had read it.
+		 */
+		int i;
+
+		if (c->big_lpt)
+			pnode->num = calc_pnode_num_from_parent(c, parent, iip);
+		for (i = 0; i < UBIFS_LPT_FANOUT; i++) {
+			struct ubifs_lprops * const lprops = &pnode->lprops[i];
+
+			lprops->free = c->leb_size;
+			lprops->flags = ubifs_categorize_lprops(c, lprops);
+		}
+	} else {
+		ubifs_assert(branch->lnum >= c->lpt_first &&
+			     branch->lnum <= c->lpt_last);
+		ubifs_assert(branch->offs >= 0 && branch->offs < c->leb_size);
+		err = ubi_read(c->ubi, branch->lnum, buf, branch->offs,
+			       c->pnode_sz);
+		if (err)
+			return ERR_PTR(err);
+		err = unpack_pnode(c, buf, pnode);
+		if (err)
+			return ERR_PTR(err);
+	}
+	err = validate_pnode(c, pnode, parent, iip);
+	if (err)
+		return ERR_PTR(err);
+	if (!c->big_lpt)
+		pnode->num = calc_pnode_num_from_parent(c, parent, iip);
+	pnode->parent = parent;
+	pnode->iip = iip;
+	set_pnode_lnum(c, pnode);
+	return pnode;
+}
+
+/**
+ * ubifs_lpt_scan_nolock - scan the LPT.
+ * @c: the UBIFS file-system description object
+ * @start_lnum: LEB number from which to start scanning
+ * @end_lnum: LEB number at which to stop scanning
+ * @scan_cb: callback function called for each lprops
+ * @data: data to be passed to the callback function
+ *
+ * This function returns %0 on success and a negative error code on failure.
+ */
+int ubifs_lpt_scan_nolock(struct ubifs_info *c, int start_lnum, int end_lnum,
+			  ubifs_lpt_scan_callback scan_cb, void *data)
+{
+	int err = 0, i, h, iip, shft;
+	struct ubifs_nnode *nnode;
+	struct ubifs_pnode *pnode;
+	struct lpt_scan_node *path;
+
+	if (start_lnum == -1) {
+		start_lnum = end_lnum + 1;
+		if (start_lnum >= c->leb_cnt)
+			start_lnum = c->main_first;
+	}
+
+	ubifs_assert(start_lnum >= c->main_first && start_lnum < c->leb_cnt);
+	ubifs_assert(end_lnum >= c->main_first && end_lnum < c->leb_cnt);
+
+	if (!c->nroot) {
+		err = ubifs_read_nnode(c, NULL, 0);
+		if (err)
+			return err;
+	}
+
+	path = kmalloc(sizeof(struct lpt_scan_node) * (c->lpt_hght + 1),
+		       GFP_NOFS);
+	if (!path)
+		return -ENOMEM;
+
+	path[0].ptr.nnode = c->nroot;
+	path[0].in_tree = 1;
+again:
+	/* Descend to the pnode containing start_lnum */
+	nnode = c->nroot;
+	i = start_lnum - c->main_first;
+	shft = c->lpt_hght * UBIFS_LPT_FANOUT_SHIFT;
+	for (h = 1; h < c->lpt_hght; h++) {
+		iip = ((i >> shft) & (UBIFS_LPT_FANOUT - 1));
+		shft -= UBIFS_LPT_FANOUT_SHIFT;
+		nnode = scan_get_nnode(c, path + h, nnode, iip);
+		if (IS_ERR(nnode)) {
+			err = PTR_ERR(nnode);
+			goto out;
+		}
+	}
+	iip = ((i >> shft) & (UBIFS_LPT_FANOUT - 1));
+	shft -= UBIFS_LPT_FANOUT_SHIFT;
+	pnode = scan_get_pnode(c, path + h, nnode, iip);
+	if (IS_ERR(pnode)) {
+		err = PTR_ERR(pnode);
+		goto out;
+	}
+	iip = (i & (UBIFS_LPT_FANOUT - 1));
+
+	/* Loop for each lprops */
+	while (1) {
+		struct ubifs_lprops *lprops = &pnode->lprops[iip];
+		int ret, lnum = lprops->lnum;
+
+		ret = scan_cb(c, lprops, path[h].in_tree, data);
+		if (ret < 0) {
+			err = ret;
+			goto out;
+		}
+		if (ret & LPT_SCAN_ADD) {
+			/* Add all the nodes in path to the tree in memory */
+			for (h = 1; h < c->lpt_hght; h++) {
+				const size_t sz = sizeof(struct ubifs_nnode);
+				struct ubifs_nnode *parent;
+
+				if (path[h].in_tree)
+					continue;
+				nnode = kmalloc(sz, GFP_NOFS);
+				if (!nnode) {
+					err = -ENOMEM;
+					goto out;
+				}
+				memcpy(nnode, &path[h].nnode, sz);
+				parent = nnode->parent;
+				parent->nbranch[nnode->iip].nnode = nnode;
+				path[h].ptr.nnode = nnode;
+				path[h].in_tree = 1;
+				path[h + 1].cnode.parent = nnode;
+			}
+			if (path[h].in_tree)
+				ubifs_ensure_cat(c, lprops);
+			else {
+				const size_t sz = sizeof(struct ubifs_pnode);
+				struct ubifs_nnode *parent;
+
+				pnode = kmalloc(sz, GFP_NOFS);
+				if (!pnode) {
+					err = -ENOMEM;
+					goto out;
+				}
+				memcpy(pnode, &path[h].pnode, sz);
+				parent = pnode->parent;
+				parent->nbranch[pnode->iip].pnode = pnode;
+				path[h].ptr.pnode = pnode;
+				path[h].in_tree = 1;
+				update_cats(c, pnode);
+				c->pnodes_have += 1;
+			}
+			err = dbg_check_lpt_nodes(c, (struct ubifs_cnode *)
+						  c->nroot, 0, 0);
+			if (err)
+				goto out;
+			err = dbg_check_cats(c);
+			if (err)
+				goto out;
+		}
+		if (ret & LPT_SCAN_STOP) {
+			err = 0;
+			break;
+		}
+		/* Get the next lprops */
+		if (lnum == end_lnum) {
+			/*
+			 * We got to the end without finding what we were
+			 * looking for
+			 */
+			err = -ENOSPC;
+			goto out;
+		}
+		if (lnum + 1 >= c->leb_cnt) {
+			/* Wrap-around to the beginning */
+			start_lnum = c->main_first;
+			goto again;
+		}
+		if (iip + 1 < UBIFS_LPT_FANOUT) {
+			/* Next lprops is in the same pnode */
+			iip += 1;
+			continue;
+		}
+		/* We need to get the next pnode. Go up until we can go right */
+		iip = pnode->iip;
+		while (1) {
+			h -= 1;
+			ubifs_assert(h >= 0);
+			nnode = path[h].ptr.nnode;
+			if (iip + 1 < UBIFS_LPT_FANOUT)
+				break;
+			iip = nnode->iip;
+		}
+		/* Go right */
+		iip += 1;
+		/* Descend to the pnode */
+		h += 1;
+		for (; h < c->lpt_hght; h++) {
+			nnode = scan_get_nnode(c, path + h, nnode, iip);
+			if (IS_ERR(nnode)) {
+				err = PTR_ERR(nnode);
+				goto out;
+			}
+			iip = 0;
+		}
+		pnode = scan_get_pnode(c, path + h, nnode, iip);
+		if (IS_ERR(pnode)) {
+			err = PTR_ERR(pnode);
+			goto out;
+		}
+		iip = 0;
+	}
+out:
+	kfree(path);
+	return err;
+}
+
+#ifdef CONFIG_UBIFS_FS_DEBUG
+
+/**
+ * dbg_chk_pnode - check a pnode.
+ * @c: the UBIFS file-system description object
+ * @pnode: pnode to check
+ * @col: pnode column
+ *
+ * This function returns %0 on success and a negative error code on failure.
+ */
+static int dbg_chk_pnode(struct ubifs_info *c, struct ubifs_pnode *pnode,
+			 int col)
+{
+	int i;
+
+	if (pnode->num != col) {
+		dbg_err("pnode num %d expected %d parent num %d iip %d",
+			pnode->num, col, pnode->parent->num, pnode->iip);
+		return -EINVAL;
+	}
+	for (i = 0; i < UBIFS_LPT_FANOUT; i++) {
+		struct ubifs_lprops *lp, *lprops = &pnode->lprops[i];
+		int lnum = (pnode->num << UBIFS_LPT_FANOUT_SHIFT) + i +
+			   c->main_first;
+		int found, cat = lprops->flags & LPROPS_CAT_MASK;
+		struct ubifs_lpt_heap *heap;
+		struct list_head *list = NULL;
+
+		if (lnum >= c->leb_cnt)
+			continue;
+		if (lprops->lnum != lnum) {
+			dbg_err("bad LEB number %d expected %d",
+				lprops->lnum, lnum);
+			return -EINVAL;
+		}
+		if (lprops->flags & LPROPS_TAKEN) {
+			if (cat != LPROPS_UNCAT) {
+				dbg_err("LEB %d taken but not uncat %d",
+					lprops->lnum, cat);
+				return -EINVAL;
+			}
+			continue;
+		}
+		if (lprops->flags & LPROPS_INDEX) {
+			switch (cat) {
+			case LPROPS_UNCAT:
+			case LPROPS_DIRTY_IDX:
+			case LPROPS_FRDI_IDX:
+				break;
+			default:
+				dbg_err("LEB %d index but cat %d",
+					lprops->lnum, cat);
+				return -EINVAL;
+			}
+		} else {
+			switch (cat) {
+			case LPROPS_UNCAT:
+			case LPROPS_DIRTY:
+			case LPROPS_FREE:
+			case LPROPS_EMPTY:
+			case LPROPS_FREEABLE:
+				break;
+			default:
+				dbg_err("LEB %d not index but cat %d",
+					lprops->lnum, cat);
+				return -EINVAL;
+			}
+		}
+		switch (cat) {
+		case LPROPS_UNCAT:
+			list = &c->uncat_list;
+			break;
+		case LPROPS_EMPTY:
+			list = &c->empty_list;
+			break;
+		case LPROPS_FREEABLE:
+			list = &c->freeable_list;
+			break;
+		case LPROPS_FRDI_IDX:
+			list = &c->frdi_idx_list;
+			break;
+		}
+		found = 0;
+		switch (cat) {
+		case LPROPS_DIRTY:
+		case LPROPS_DIRTY_IDX:
+		case LPROPS_FREE:
+			heap = &c->lpt_heap[cat - 1];
+			if (lprops->hpos < heap->cnt &&
+			    heap->arr[lprops->hpos] == lprops)
+				found = 1;
+			break;
+		case LPROPS_UNCAT:
+		case LPROPS_EMPTY:
+		case LPROPS_FREEABLE:
+		case LPROPS_FRDI_IDX:
+			list_for_each_entry(lp, list, list)
+				if (lprops == lp) {
+					found = 1;
+					break;
+				}
+			break;
+		}
+		if (!found) {
+			dbg_err("LEB %d cat %d not found in cat heap/list",
+				lprops->lnum, cat);
+			return -EINVAL;
+		}
+		switch (cat) {
+		case LPROPS_EMPTY:
+			if (lprops->free != c->leb_size) {
+				dbg_err("LEB %d cat %d free %d dirty %d",
+					lprops->lnum, cat, lprops->free,
+					lprops->dirty);
+				return -EINVAL;
+			}
+		case LPROPS_FREEABLE:
+		case LPROPS_FRDI_IDX:
+			if (lprops->free + lprops->dirty != c->leb_size) {
+				dbg_err("LEB %d cat %d free %d dirty %d",
+					lprops->lnum, cat, lprops->free,
+					lprops->dirty);
+				return -EINVAL;
+			}
+		}
+	}
+	return 0;
+}
+
+/**
+ * dbg_check_lpt_nodes - check nnodes and pnodes.
+ * @c: the UBIFS file-system description object
+ * @cnode: next cnode (nnode or pnode) to check
+ * @row: row of cnode (root is zero)
+ * @col: column of cnode (leftmost is zero)
+ *
+ * This function returns %0 on success and a negative error code on failure.
+ */
+int dbg_check_lpt_nodes(struct ubifs_info *c, struct ubifs_cnode *cnode,
+			int row, int col)
+{
+	struct ubifs_nnode *nnode, *nn;
+	struct ubifs_cnode *cn;
+	int num, iip = 0, err;
+
+	if (!(ubifs_chk_flags & UBIFS_CHK_LPROPS))
+		return 0;
+
+	while (cnode) {
+		ubifs_assert(row >= 0);
+		nnode = cnode->parent;
+		if (cnode->level) {
+			/* cnode is a nnode */
+			num = calc_nnode_num(row, col);
+			if (cnode->num != num) {
+				dbg_err("nnode num %d expected %d "
+					"parent num %d iip %d", cnode->num, num,
+					(nnode ? nnode->num : 0), cnode->iip);
+				return -EINVAL;
+			}
+			nn = (struct ubifs_nnode *)cnode;
+			while (iip < UBIFS_LPT_FANOUT) {
+				cn = nn->nbranch[iip].cnode;
+				if (cn) {
+					/* Go down */
+					row += 1;
+					col <<= UBIFS_LPT_FANOUT_SHIFT;
+					col += iip;
+					iip = 0;
+					cnode = cn;
+					break;
+				}
+				/* Go right */
+				iip += 1;
+			}
+			if (iip < UBIFS_LPT_FANOUT)
+				continue;
+		} else {
+			struct ubifs_pnode *pnode;
+
+			/* cnode is a pnode */
+			pnode = (struct ubifs_pnode *)cnode;
+			err = dbg_chk_pnode(c, pnode, col);
+			if (err)
+				return err;
+		}
+		/* Go up and to the right */
+		row -= 1;
+		col >>= UBIFS_LPT_FANOUT_SHIFT;
+		iip = cnode->iip + 1;
+		cnode = (struct ubifs_cnode *)nnode;
+	}
+	return 0;
+}
+
+#endif /* CONFIG_UBIFS_FS_DEBUG */
diff --git a/fs/ubifs/lpt_commit.c b/fs/ubifs/lpt_commit.c
new file mode 100644
index 00000000000..5f0b83e20af
--- /dev/null
+++ b/fs/ubifs/lpt_commit.c
@@ -0,0 +1,1648 @@
+/*
+ * This file is part of UBIFS.
+ *
+ * Copyright (C) 2006-2008 Nokia Corporation.
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 as published by
+ * the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
+ * more details.
+ *
+ * You should have received a copy of the GNU General Public License along with
+ * this program; if not, write to the Free Software Foundation, Inc., 51
+ * Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
+ *
+ * Authors: Adrian Hunter
+ *          Artem Bityutskiy (Битюцкий Артём)
+ */
+
+/*
+ * This file implements commit-related functionality of the LEB properties
+ * subsystem.
+ */
+
+#include <linux/crc16.h>
+#include "ubifs.h"
+
+/**
+ * first_dirty_cnode - find first dirty cnode.
+ * @c: UBIFS file-system description object
+ * @nnode: nnode at which to start
+ *
+ * This function returns the first dirty cnode or %NULL if there is not one.
+ */
+static struct ubifs_cnode *first_dirty_cnode(struct ubifs_nnode *nnode)
+{
+	ubifs_assert(nnode);
+	while (1) {
+		int i, cont = 0;
+
+		for (i = 0; i < UBIFS_LPT_FANOUT; i++) {
+			struct ubifs_cnode *cnode;
+
+			cnode = nnode->nbranch[i].cnode;
+			if (cnode &&
+			    test_bit(DIRTY_CNODE, &cnode->flags)) {
+				if (cnode->level == 0)
+					return cnode;
+				nnode = (struct ubifs_nnode *)cnode;
+				cont = 1;
+				break;
+			}
+		}
+		if (!cont)
+			return (struct ubifs_cnode *)nnode;
+	}
+}
+
+/**
+ * next_dirty_cnode - find next dirty cnode.
+ * @cnode: cnode from which to begin searching
+ *
+ * This function returns the next dirty cnode or %NULL if there is not one.
+ */
+static struct ubifs_cnode *next_dirty_cnode(struct ubifs_cnode *cnode)
+{
+	struct ubifs_nnode *nnode;
+	int i;
+
+	ubifs_assert(cnode);
+	nnode = cnode->parent;
+	if (!nnode)
+		return NULL;
+	for (i = cnode->iip + 1; i < UBIFS_LPT_FANOUT; i++) {
+		cnode = nnode->nbranch[i].cnode;
+		if (cnode && test_bit(DIRTY_CNODE, &cnode->flags)) {
+			if (cnode->level == 0)
+				return cnode; /* cnode is a pnode */
+			/* cnode is a nnode */
+			return first_dirty_cnode((struct ubifs_nnode *)cnode);
+		}
+	}
+	return (struct ubifs_cnode *)nnode;
+}
+
+/**
+ * get_cnodes_to_commit - create list of dirty cnodes to commit.
+ * @c: UBIFS file-system description object
+ *
+ * This function returns the number of cnodes to commit.
+ */
+static int get_cnodes_to_commit(struct ubifs_info *c)
+{
+	struct ubifs_cnode *cnode, *cnext;
+	int cnt = 0;
+
+	if (!c->nroot)
+		return 0;
+
+	if (!test_bit(DIRTY_CNODE, &c->nroot->flags))
+		return 0;
+
+	c->lpt_cnext = first_dirty_cnode(c->nroot);
+	cnode = c->lpt_cnext;
+	if (!cnode)
+		return 0;
+	cnt += 1;
+	while (1) {
+		ubifs_assert(!test_bit(COW_ZNODE, &cnode->flags));
+		__set_bit(COW_ZNODE, &cnode->flags);
+		cnext = next_dirty_cnode(cnode);
+		if (!cnext) {
+			cnode->cnext = c->lpt_cnext;
+			break;
+		}
+		cnode->cnext = cnext;
+		cnode = cnext;
+		cnt += 1;
+	}
+	dbg_cmt("committing %d cnodes", cnt);
+	dbg_lp("committing %d cnodes", cnt);
+	ubifs_assert(cnt == c->dirty_nn_cnt + c->dirty_pn_cnt);
+	return cnt;
+}
+
+/**
+ * upd_ltab - update LPT LEB properties.
+ * @c: UBIFS file-system description object
+ * @lnum: LEB number
+ * @free: amount of free space
+ * @dirty: amount of dirty space to add
+ */
+static void upd_ltab(struct ubifs_info *c, int lnum, int free, int dirty)
+{
+	dbg_lp("LEB %d free %d dirty %d to %d +%d",
+	       lnum, c->ltab[lnum - c->lpt_first].free,
+	       c->ltab[lnum - c->lpt_first].dirty, free, dirty);
+	ubifs_assert(lnum >= c->lpt_first && lnum <= c->lpt_last);
+	c->ltab[lnum - c->lpt_first].free = free;
+	c->ltab[lnum - c->lpt_first].dirty += dirty;
+}
+
+/**
+ * alloc_lpt_leb - allocate an LPT LEB that is empty.
+ * @c: UBIFS file-system description object
+ * @lnum: LEB number is passed and returned here
+ *
+ * This function finds the next empty LEB in the ltab starting from @lnum. If a
+ * an empty LEB is found it is returned in @lnum and the function returns %0.
+ * Otherwise the function returns -ENOSPC.  Note however, that LPT is designed
+ * never to run out of space.
+ */
+static int alloc_lpt_leb(struct ubifs_info *c, int *lnum)
+{
+	int i, n;
+
+	n = *lnum - c->lpt_first + 1;
+	for (i = n; i < c->lpt_lebs; i++) {
+		if (c->ltab[i].tgc || c->ltab[i].cmt)
+			continue;
+		if (c->ltab[i].free == c->leb_size) {
+			c->ltab[i].cmt = 1;
+			*lnum = i + c->lpt_first;
+			return 0;
+		}
+	}
+
+	for (i = 0; i < n; i++) {
+		if (c->ltab[i].tgc || c->ltab[i].cmt)
+			continue;
+		if (c->ltab[i].free == c->leb_size) {
+			c->ltab[i].cmt = 1;
+			*lnum = i + c->lpt_first;
+			return 0;
+		}
+	}
+	dbg_err("last LEB %d", *lnum);
+	dump_stack();
+	return -ENOSPC;
+}
+
+/**
+ * layout_cnodes - layout cnodes for commit.
+ * @c: UBIFS file-system description object
+ *
+ * This function returns %0 on success and a negative error code on failure.
+ */
+static int layout_cnodes(struct ubifs_info *c)
+{
+	int lnum, offs, len, alen, done_lsave, done_ltab, err;
+	struct ubifs_cnode *cnode;
+
+	cnode = c->lpt_cnext;
+	if (!cnode)
+		return 0;
+	lnum = c->nhead_lnum;
+	offs = c->nhead_offs;
+	/* Try to place lsave and ltab nicely */
+	done_lsave = !c->big_lpt;
+	done_ltab = 0;
+	if (!done_lsave && offs + c->lsave_sz <= c->leb_size) {
+		done_lsave = 1;
+		c->lsave_lnum = lnum;
+		c->lsave_offs = offs;
+		offs += c->lsave_sz;
+	}
+
+	if (offs + c->ltab_sz <= c->leb_size) {
+		done_ltab = 1;
+		c->ltab_lnum = lnum;
+		c->ltab_offs = offs;
+		offs += c->ltab_sz;
+	}
+
+	do {
+		if (cnode->level) {
+			len = c->nnode_sz;
+			c->dirty_nn_cnt -= 1;
+		} else {
+			len = c->pnode_sz;
+			c->dirty_pn_cnt -= 1;
+		}
+		while (offs + len > c->leb_size) {
+			alen = ALIGN(offs, c->min_io_size);
+			upd_ltab(c, lnum, c->leb_size - alen, alen - offs);
+			err = alloc_lpt_leb(c, &lnum);
+			if (err)
+				return err;
+			offs = 0;
+			ubifs_assert(lnum >= c->lpt_first &&
+				     lnum <= c->lpt_last);
+			/* Try to place lsave and ltab nicely */
+			if (!done_lsave) {
+				done_lsave = 1;
+				c->lsave_lnum = lnum;
+				c->lsave_offs = offs;
+				offs += c->lsave_sz;
+				continue;
+			}
+			if (!done_ltab) {
+				done_ltab = 1;
+				c->ltab_lnum = lnum;
+				c->ltab_offs = offs;
+				offs += c->ltab_sz;
+				continue;
+			}
+			break;
+		}
+		if (cnode->parent) {
+			cnode->parent->nbranch[cnode->iip].lnum = lnum;
+			cnode->parent->nbranch[cnode->iip].offs = offs;
+		} else {
+			c->lpt_lnum = lnum;
+			c->lpt_offs = offs;
+		}
+		offs += len;
+		cnode = cnode->cnext;
+	} while (cnode && cnode != c->lpt_cnext);
+
+	/* Make sure to place LPT's save table */
+	if (!done_lsave) {
+		if (offs + c->lsave_sz > c->leb_size) {
+			alen = ALIGN(offs, c->min_io_size);
+			upd_ltab(c, lnum, c->leb_size - alen, alen - offs);
+			err = alloc_lpt_leb(c, &lnum);
+			if (err)
+				return err;
+			offs = 0;
+			ubifs_assert(lnum >= c->lpt_first &&
+				     lnum <= c->lpt_last);
+		}
+		done_lsave = 1;
+		c->lsave_lnum = lnum;
+		c->lsave_offs = offs;
+		offs += c->lsave_sz;
+	}
+
+	/* Make sure to place LPT's own lprops table */
+	if (!done_ltab) {
+		if (offs + c->ltab_sz > c->leb_size) {
+			alen = ALIGN(offs, c->min_io_size);
+			upd_ltab(c, lnum, c->leb_size - alen, alen - offs);
+			err = alloc_lpt_leb(c, &lnum);
+			if (err)
+				return err;
+			offs = 0;
+			ubifs_assert(lnum >= c->lpt_first &&
+				     lnum <= c->lpt_last);
+		}
+		done_ltab = 1;
+		c->ltab_lnum = lnum;
+		c->ltab_offs = offs;
+		offs += c->ltab_sz;
+	}
+
+	alen = ALIGN(offs, c->min_io_size);
+	upd_ltab(c, lnum, c->leb_size - alen, alen - offs);
+	return 0;
+}
+
+/**
+ * realloc_lpt_leb - allocate an LPT LEB that is empty.
+ * @c: UBIFS file-system description object
+ * @lnum: LEB number is passed and returned here
+ *
+ * This function duplicates exactly the results of the function alloc_lpt_leb.
+ * It is used during end commit to reallocate the same LEB numbers that were
+ * allocated by alloc_lpt_leb during start commit.
+ *
+ * This function finds the next LEB that was allocated by the alloc_lpt_leb
+ * function starting from @lnum. If a LEB is found it is returned in @lnum and
+ * the function returns %0. Otherwise the function returns -ENOSPC.
+ * Note however, that LPT is designed never to run out of space.
+ */
+static int realloc_lpt_leb(struct ubifs_info *c, int *lnum)
+{
+	int i, n;
+
+	n = *lnum - c->lpt_first + 1;
+	for (i = n; i < c->lpt_lebs; i++)
+		if (c->ltab[i].cmt) {
+			c->ltab[i].cmt = 0;
+			*lnum = i + c->lpt_first;
+			return 0;
+		}
+
+	for (i = 0; i < n; i++)
+		if (c->ltab[i].cmt) {
+			c->ltab[i].cmt = 0;
+			*lnum = i + c->lpt_first;
+			return 0;
+		}
+	dbg_err("last LEB %d", *lnum);
+	dump_stack();
+	return -ENOSPC;
+}
+
+/**
+ * write_cnodes - write cnodes for commit.
+ * @c: UBIFS file-system description object
+ *
+ * This function returns %0 on success and a negative error code on failure.
+ */
+static int write_cnodes(struct ubifs_info *c)
+{
+	int lnum, offs, len, from, err, wlen, alen, done_ltab, done_lsave;
+	struct ubifs_cnode *cnode;
+	void *buf = c->lpt_buf;
+
+	cnode = c->lpt_cnext;
+	if (!cnode)
+		return 0;
+	lnum = c->nhead_lnum;
+	offs = c->nhead_offs;
+	from = offs;
+	/* Ensure empty LEB is unmapped */
+	if (offs == 0) {
+		err = ubifs_leb_unmap(c, lnum);
+		if (err)
+			return err;
+	}
+	/* Try to place lsave and ltab nicely */
+	done_lsave = !c->big_lpt;
+	done_ltab = 0;
+	if (!done_lsave && offs + c->lsave_sz <= c->leb_size) {
+		done_lsave = 1;
+		ubifs_pack_lsave(c, buf + offs, c->lsave);
+		offs += c->lsave_sz;
+	}
+
+	if (offs + c->ltab_sz <= c->leb_size) {
+		done_ltab = 1;
+		ubifs_pack_ltab(c, buf + offs, c->ltab_cmt);
+		offs += c->ltab_sz;
+	}
+
+	/* Loop for each cnode */
+	do {
+		if (cnode->level)
+			len = c->nnode_sz;
+		else
+			len = c->pnode_sz;
+		while (offs + len > c->leb_size) {
+			wlen = offs - from;
+			if (wlen) {
+				alen = ALIGN(wlen, c->min_io_size);
+				memset(buf + offs, 0xff, alen - wlen);
+				err = ubifs_leb_write(c, lnum, buf + from, from,
+						       alen, UBI_SHORTTERM);
+				if (err)
+					return err;
+			}
+			err = realloc_lpt_leb(c, &lnum);
+			if (err)
+				return err;
+			offs = 0;
+			from = 0;
+			ubifs_assert(lnum >= c->lpt_first &&
+				     lnum <= c->lpt_last);
+			err = ubifs_leb_unmap(c, lnum);
+			if (err)
+				return err;
+			/* Try to place lsave and ltab nicely */
+			if (!done_lsave) {
+				done_lsave = 1;
+				ubifs_pack_lsave(c, buf + offs, c->lsave);
+				offs += c->lsave_sz;
+				continue;
+			}
+			if (!done_ltab) {
+				done_ltab = 1;
+				ubifs_pack_ltab(c, buf + offs, c->ltab_cmt);
+				offs += c->ltab_sz;
+				continue;
+			}
+			break;
+		}
+		if (cnode->level)
+			ubifs_pack_nnode(c, buf + offs,
+					 (struct ubifs_nnode *)cnode);
+		else
+			ubifs_pack_pnode(c, buf + offs,
+					 (struct ubifs_pnode *)cnode);
+		/*
+		 * The reason for the barriers is the same as in case of TNC.
+		 * See comment in 'write_index()'. 'dirty_cow_nnode()' and
+		 * 'dirty_cow_pnode()' are the functions for which this is
+		 * important.
+		 */
+		clear_bit(DIRTY_CNODE, &cnode->flags);
+		smp_mb__before_clear_bit();
+		clear_bit(COW_ZNODE, &cnode->flags);
+		smp_mb__after_clear_bit();
+		offs += len;
+		cnode = cnode->cnext;
+	} while (cnode && cnode != c->lpt_cnext);
+
+	/* Make sure to place LPT's save table */
+	if (!done_lsave) {
+		if (offs + c->lsave_sz > c->leb_size) {
+			wlen = offs - from;
+			alen = ALIGN(wlen, c->min_io_size);
+			memset(buf + offs, 0xff, alen - wlen);
+			err = ubifs_leb_write(c, lnum, buf + from, from, alen,
+					      UBI_SHORTTERM);
+			if (err)
+				return err;
+			err = realloc_lpt_leb(c, &lnum);
+			if (err)
+				return err;
+			offs = 0;
+			ubifs_assert(lnum >= c->lpt_first &&
+				     lnum <= c->lpt_last);
+			err = ubifs_leb_unmap(c, lnum);
+			if (err)
+				return err;
+		}
+		done_lsave = 1;
+		ubifs_pack_lsave(c, buf + offs, c->lsave);
+		offs += c->lsave_sz;
+	}
+
+	/* Make sure to place LPT's own lprops table */
+	if (!done_ltab) {
+		if (offs + c->ltab_sz > c->leb_size) {
+			wlen = offs - from;
+			alen = ALIGN(wlen, c->min_io_size);
+			memset(buf + offs, 0xff, alen - wlen);
+			err = ubifs_leb_write(c, lnum, buf + from, from, alen,
+					      UBI_SHORTTERM);
+			if (err)
+				return err;
+			err = realloc_lpt_leb(c, &lnum);
+			if (err)
+				return err;
+			offs = 0;
+			ubifs_assert(lnum >= c->lpt_first &&
+				     lnum <= c->lpt_last);
+			err = ubifs_leb_unmap(c, lnum);
+			if (err)
+				return err;
+		}
+		done_ltab = 1;
+		ubifs_pack_ltab(c, buf + offs, c->ltab_cmt);
+		offs += c->ltab_sz;
+	}
+
+	/* Write remaining data in buffer */
+	wlen = offs - from;
+	alen = ALIGN(wlen, c->min_io_size);
+	memset(buf + offs, 0xff, alen - wlen);
+	err = ubifs_leb_write(c, lnum, buf + from, from, alen, UBI_SHORTTERM);
+	if (err)
+		return err;
+	c->nhead_lnum = lnum;
+	c->nhead_offs = ALIGN(offs, c->min_io_size);
+
+	dbg_lp("LPT root is at %d:%d", c->lpt_lnum, c->lpt_offs);
+	dbg_lp("LPT head is at %d:%d", c->nhead_lnum, c->nhead_offs);
+	dbg_lp("LPT ltab is at %d:%d", c->ltab_lnum, c->ltab_offs);
+	if (c->big_lpt)
+		dbg_lp("LPT lsave is at %d:%d", c->lsave_lnum, c->lsave_offs);
+	return 0;
+}
+
+/**
+ * next_pnode - find next pnode.
+ * @c: UBIFS file-system description object
+ * @pnode: pnode
+ *
+ * This function returns the next pnode or %NULL if there are no more pnodes.
+ */
+static struct ubifs_pnode *next_pnode(struct ubifs_info *c,
+				      struct ubifs_pnode *pnode)
+{
+	struct ubifs_nnode *nnode;
+	int iip;
+
+	/* Try to go right */
+	nnode = pnode->parent;
+	iip = pnode->iip + 1;
+	if (iip < UBIFS_LPT_FANOUT) {
+		/* We assume here that LEB zero is never an LPT LEB */
+		if (nnode->nbranch[iip].lnum)
+			return ubifs_get_pnode(c, nnode, iip);
+		else
+			return NULL;
+	}
+
+	/* Go up while can't go right */
+	do {
+		iip = nnode->iip + 1;
+		nnode = nnode->parent;
+		if (!nnode)
+			return NULL;
+		/* We assume here that LEB zero is never an LPT LEB */
+	} while (iip >= UBIFS_LPT_FANOUT || !nnode->nbranch[iip].lnum);
+
+	/* Go right */
+	nnode = ubifs_get_nnode(c, nnode, iip);
+	if (IS_ERR(nnode))
+		return (void *)nnode;
+
+	/* Go down to level 1 */
+	while (nnode->level > 1) {
+		nnode = ubifs_get_nnode(c, nnode, 0);
+		if (IS_ERR(nnode))
+			return (void *)nnode;
+	}
+
+	return ubifs_get_pnode(c, nnode, 0);
+}
+
+/**
+ * pnode_lookup - lookup a pnode in the LPT.
+ * @c: UBIFS file-system description object
+ * @i: pnode number (0 to main_lebs - 1)
+ *
+ * This function returns a pointer to the pnode on success or a negative
+ * error code on failure.
+ */
+static struct ubifs_pnode *pnode_lookup(struct ubifs_info *c, int i)
+{
+	int err, h, iip, shft;
+	struct ubifs_nnode *nnode;
+
+	if (!c->nroot) {
+		err = ubifs_read_nnode(c, NULL, 0);
+		if (err)
+			return ERR_PTR(err);
+	}
+	i <<= UBIFS_LPT_FANOUT_SHIFT;
+	nnode = c->nroot;
+	shft = c->lpt_hght * UBIFS_LPT_FANOUT_SHIFT;
+	for (h = 1; h < c->lpt_hght; h++) {
+		iip = ((i >> shft) & (UBIFS_LPT_FANOUT - 1));
+		shft -= UBIFS_LPT_FANOUT_SHIFT;
+		nnode = ubifs_get_nnode(c, nnode, iip);
+		if (IS_ERR(nnode))
+			return ERR_PTR(PTR_ERR(nnode));
+	}
+	iip = ((i >> shft) & (UBIFS_LPT_FANOUT - 1));
+	return ubifs_get_pnode(c, nnode, iip);
+}
+
+/**
+ * add_pnode_dirt - add dirty space to LPT LEB properties.
+ * @c: UBIFS file-system description object
+ * @pnode: pnode for which to add dirt
+ */
+static void add_pnode_dirt(struct ubifs_info *c, struct ubifs_pnode *pnode)
+{
+	ubifs_add_lpt_dirt(c, pnode->parent->nbranch[pnode->iip].lnum,
+			   c->pnode_sz);
+}
+
+/**
+ * do_make_pnode_dirty - mark a pnode dirty.
+ * @c: UBIFS file-system description object
+ * @pnode: pnode to mark dirty
+ */
+static void do_make_pnode_dirty(struct ubifs_info *c, struct ubifs_pnode *pnode)
+{
+	/* Assumes cnext list is empty i.e. not called during commit */
+	if (!test_and_set_bit(DIRTY_CNODE, &pnode->flags)) {
+		struct ubifs_nnode *nnode;
+
+		c->dirty_pn_cnt += 1;
+		add_pnode_dirt(c, pnode);
+		/* Mark parent and ancestors dirty too */
+		nnode = pnode->parent;
+		while (nnode) {
+			if (!test_and_set_bit(DIRTY_CNODE, &nnode->flags)) {
+				c->dirty_nn_cnt += 1;
+				ubifs_add_nnode_dirt(c, nnode);
+				nnode = nnode->parent;
+			} else
+				break;
+		}
+	}
+}
+
+/**
+ * make_tree_dirty - mark the entire LEB properties tree dirty.
+ * @c: UBIFS file-system description object
+ *
+ * This function is used by the "small" LPT model to cause the entire LEB
+ * properties tree to be written.  The "small" LPT model does not use LPT
+ * garbage collection because it is more efficient to write the entire tree
+ * (because it is small).
+ *
+ * This function returns %0 on success and a negative error code on failure.
+ */
+static int make_tree_dirty(struct ubifs_info *c)
+{
+	struct ubifs_pnode *pnode;
+
+	pnode = pnode_lookup(c, 0);
+	while (pnode) {
+		do_make_pnode_dirty(c, pnode);
+		pnode = next_pnode(c, pnode);
+		if (IS_ERR(pnode))
+			return PTR_ERR(pnode);
+	}
+	return 0;
+}
+
+/**
+ * need_write_all - determine if the LPT area is running out of free space.
+ * @c: UBIFS file-system description object
+ *
+ * This function returns %1 if the LPT area is running out of free space and %0
+ * if it is not.
+ */
+static int need_write_all(struct ubifs_info *c)
+{
+	long long free = 0;
+	int i;
+
+	for (i = 0; i < c->lpt_lebs; i++) {
+		if (i + c->lpt_first == c->nhead_lnum)
+			free += c->leb_size - c->nhead_offs;
+		else if (c->ltab[i].free == c->leb_size)
+			free += c->leb_size;
+		else if (c->ltab[i].free + c->ltab[i].dirty == c->leb_size)
+			free += c->leb_size;
+	}
+	/* Less than twice the size left */
+	if (free <= c->lpt_sz * 2)
+		return 1;
+	return 0;
+}
+
+/**
+ * lpt_tgc_start - start trivial garbage collection of LPT LEBs.
+ * @c: UBIFS file-system description object
+ *
+ * LPT trivial garbage collection is where a LPT LEB contains only dirty and
+ * free space and so may be reused as soon as the next commit is completed.
+ * This function is called during start commit to mark LPT LEBs for trivial GC.
+ */
+static void lpt_tgc_start(struct ubifs_info *c)
+{
+	int i;
+
+	for (i = 0; i < c->lpt_lebs; i++) {
+		if (i + c->lpt_first == c->nhead_lnum)
+			continue;
+		if (c->ltab[i].dirty > 0 &&
+		    c->ltab[i].free + c->ltab[i].dirty == c->leb_size) {
+			c->ltab[i].tgc = 1;
+			c->ltab[i].free = c->leb_size;
+			c->ltab[i].dirty = 0;
+			dbg_lp("LEB %d", i + c->lpt_first);
+		}
+	}
+}
+
+/**
+ * lpt_tgc_end - end trivial garbage collection of LPT LEBs.
+ * @c: UBIFS file-system description object
+ *
+ * LPT trivial garbage collection is where a LPT LEB contains only dirty and
+ * free space and so may be reused as soon as the next commit is completed.
+ * This function is called after the commit is completed (master node has been
+ * written) and unmaps LPT LEBs that were marked for trivial GC.
+ */
+static int lpt_tgc_end(struct ubifs_info *c)
+{
+	int i, err;
+
+	for (i = 0; i < c->lpt_lebs; i++)
+		if (c->ltab[i].tgc) {
+			err = ubifs_leb_unmap(c, i + c->lpt_first);
+			if (err)
+				return err;
+			c->ltab[i].tgc = 0;
+			dbg_lp("LEB %d", i + c->lpt_first);
+		}
+	return 0;
+}
+
+/**
+ * populate_lsave - fill the lsave array with important LEB numbers.
+ * @c: the UBIFS file-system description object
+ *
+ * This function is only called for the "big" model. It records a small number
+ * of LEB numbers of important LEBs.  Important LEBs are ones that are (from
+ * most important to least important): empty, freeable, freeable index, dirty
+ * index, dirty or free. Upon mount, we read this list of LEB numbers and bring
+ * their pnodes into memory.  That will stop us from having to scan the LPT
+ * straight away. For the "small" model we assume that scanning the LPT is no
+ * big deal.
+ */
+static void populate_lsave(struct ubifs_info *c)
+{
+	struct ubifs_lprops *lprops;
+	struct ubifs_lpt_heap *heap;
+	int i, cnt = 0;
+
+	ubifs_assert(c->big_lpt);
+	if (!(c->lpt_drty_flgs & LSAVE_DIRTY)) {
+		c->lpt_drty_flgs |= LSAVE_DIRTY;
+		ubifs_add_lpt_dirt(c, c->lsave_lnum, c->lsave_sz);
+	}
+	list_for_each_entry(lprops, &c->empty_list, list) {
+		c->lsave[cnt++] = lprops->lnum;
+		if (cnt >= c->lsave_cnt)
+			return;
+	}
+	list_for_each_entry(lprops, &c->freeable_list, list) {
+		c->lsave[cnt++] = lprops->lnum;
+		if (cnt >= c->lsave_cnt)
+			return;
+	}
+	list_for_each_entry(lprops, &c->frdi_idx_list, list) {
+		c->lsave[cnt++] = lprops->lnum;
+		if (cnt >= c->lsave_cnt)
+			return;
+	}
+	heap = &c->lpt_heap[LPROPS_DIRTY_IDX - 1];
+	for (i = 0; i < heap->cnt; i++) {
+		c->lsave[cnt++] = heap->arr[i]->lnum;
+		if (cnt >= c->lsave_cnt)
+			return;
+	}
+	heap = &c->lpt_heap[LPROPS_DIRTY - 1];
+	for (i = 0; i < heap->cnt; i++) {
+		c->lsave[cnt++] = heap->arr[i]->lnum;
+		if (cnt >= c->lsave_cnt)
+			return;
+	}
+	heap = &c->lpt_heap[LPROPS_FREE - 1];
+	for (i = 0; i < heap->cnt; i++) {
+		c->lsave[cnt++] = heap->arr[i]->lnum;
+		if (cnt >= c->lsave_cnt)
+			return;
+	}
+	/* Fill it up completely */
+	while (cnt < c->lsave_cnt)
+		c->lsave[cnt++] = c->main_first;
+}
+
+/**
+ * nnode_lookup - lookup a nnode in the LPT.
+ * @c: UBIFS file-system description object
+ * @i: nnode number
+ *
+ * This function returns a pointer to the nnode on success or a negative
+ * error code on failure.
+ */
+static struct ubifs_nnode *nnode_lookup(struct ubifs_info *c, int i)
+{
+	int err, iip;
+	struct ubifs_nnode *nnode;
+
+	if (!c->nroot) {
+		err = ubifs_read_nnode(c, NULL, 0);
+		if (err)
+			return ERR_PTR(err);
+	}
+	nnode = c->nroot;
+	while (1) {
+		iip = i & (UBIFS_LPT_FANOUT - 1);
+		i >>= UBIFS_LPT_FANOUT_SHIFT;
+		if (!i)
+			break;
+		nnode = ubifs_get_nnode(c, nnode, iip);
+		if (IS_ERR(nnode))
+			return nnode;
+	}
+	return nnode;
+}
+
+/**
+ * make_nnode_dirty - find a nnode and, if found, make it dirty.
+ * @c: UBIFS file-system description object
+ * @node_num: nnode number of nnode to make dirty
+ * @lnum: LEB number where nnode was written
+ * @offs: offset where nnode was written
+ *
+ * This function is used by LPT garbage collection.  LPT garbage collection is
+ * used only for the "big" LPT model (c->big_lpt == 1).  Garbage collection
+ * simply involves marking all the nodes in the LEB being garbage-collected as
+ * dirty.  The dirty nodes are written next commit, after which the LEB is free
+ * to be reused.
+ *
+ * This function returns %0 on success and a negative error code on failure.
+ */
+static int make_nnode_dirty(struct ubifs_info *c, int node_num, int lnum,
+			    int offs)
+{
+	struct ubifs_nnode *nnode;
+
+	nnode = nnode_lookup(c, node_num);
+	if (IS_ERR(nnode))
+		return PTR_ERR(nnode);
+	if (nnode->parent) {
+		struct ubifs_nbranch *branch;
+
+		branch = &nnode->parent->nbranch[nnode->iip];
+		if (branch->lnum != lnum || branch->offs != offs)
+			return 0; /* nnode is obsolete */
+	} else if (c->lpt_lnum != lnum || c->lpt_offs != offs)
+			return 0; /* nnode is obsolete */
+	/* Assumes cnext list is empty i.e. not called during commit */
+	if (!test_and_set_bit(DIRTY_CNODE, &nnode->flags)) {
+		c->dirty_nn_cnt += 1;
+		ubifs_add_nnode_dirt(c, nnode);
+		/* Mark parent and ancestors dirty too */
+		nnode = nnode->parent;
+		while (nnode) {
+			if (!test_and_set_bit(DIRTY_CNODE, &nnode->flags)) {
+				c->dirty_nn_cnt += 1;
+				ubifs_add_nnode_dirt(c, nnode);
+				nnode = nnode->parent;
+			} else
+				break;
+		}
+	}
+	return 0;
+}
+
+/**
+ * make_pnode_dirty - find a pnode and, if found, make it dirty.
+ * @c: UBIFS file-system description object
+ * @node_num: pnode number of pnode to make dirty
+ * @lnum: LEB number where pnode was written
+ * @offs: offset where pnode was written
+ *
+ * This function is used by LPT garbage collection.  LPT garbage collection is
+ * used only for the "big" LPT model (c->big_lpt == 1).  Garbage collection
+ * simply involves marking all the nodes in the LEB being garbage-collected as
+ * dirty.  The dirty nodes are written next commit, after which the LEB is free
+ * to be reused.
+ *
+ * This function returns %0 on success and a negative error code on failure.
+ */
+static int make_pnode_dirty(struct ubifs_info *c, int node_num, int lnum,
+			    int offs)
+{
+	struct ubifs_pnode *pnode;
+	struct ubifs_nbranch *branch;
+
+	pnode = pnode_lookup(c, node_num);
+	if (IS_ERR(pnode))
+		return PTR_ERR(pnode);
+	branch = &pnode->parent->nbranch[pnode->iip];
+	if (branch->lnum != lnum || branch->offs != offs)
+		return 0;
+	do_make_pnode_dirty(c, pnode);
+	return 0;
+}
+
+/**
+ * make_ltab_dirty - make ltab node dirty.
+ * @c: UBIFS file-system description object
+ * @lnum: LEB number where ltab was written
+ * @offs: offset where ltab was written
+ *
+ * This function is used by LPT garbage collection.  LPT garbage collection is
+ * used only for the "big" LPT model (c->big_lpt == 1).  Garbage collection
+ * simply involves marking all the nodes in the LEB being garbage-collected as
+ * dirty.  The dirty nodes are written next commit, after which the LEB is free
+ * to be reused.
+ *
+ * This function returns %0 on success and a negative error code on failure.
+ */
+static int make_ltab_dirty(struct ubifs_info *c, int lnum, int offs)
+{
+	if (lnum != c->ltab_lnum || offs != c->ltab_offs)
+		return 0; /* This ltab node is obsolete */
+	if (!(c->lpt_drty_flgs & LTAB_DIRTY)) {
+		c->lpt_drty_flgs |= LTAB_DIRTY;
+		ubifs_add_lpt_dirt(c, c->ltab_lnum, c->ltab_sz);
+	}
+	return 0;
+}
+
+/**
+ * make_lsave_dirty - make lsave node dirty.
+ * @c: UBIFS file-system description object
+ * @lnum: LEB number where lsave was written
+ * @offs: offset where lsave was written
+ *
+ * This function is used by LPT garbage collection.  LPT garbage collection is
+ * used only for the "big" LPT model (c->big_lpt == 1).  Garbage collection
+ * simply involves marking all the nodes in the LEB being garbage-collected as
+ * dirty.  The dirty nodes are written next commit, after which the LEB is free
+ * to be reused.
+ *
+ * This function returns %0 on success and a negative error code on failure.
+ */
+static int make_lsave_dirty(struct ubifs_info *c, int lnum, int offs)
+{
+	if (lnum != c->lsave_lnum || offs != c->lsave_offs)
+		return 0; /* This lsave node is obsolete */
+	if (!(c->lpt_drty_flgs & LSAVE_DIRTY)) {
+		c->lpt_drty_flgs |= LSAVE_DIRTY;
+		ubifs_add_lpt_dirt(c, c->lsave_lnum, c->lsave_sz);
+	}
+	return 0;
+}
+
+/**
+ * make_node_dirty - make node dirty.
+ * @c: UBIFS file-system description object
+ * @node_type: LPT node type
+ * @node_num: node number
+ * @lnum: LEB number where node was written
+ * @offs: offset where node was written
+ *
+ * This function is used by LPT garbage collection.  LPT garbage collection is
+ * used only for the "big" LPT model (c->big_lpt == 1).  Garbage collection
+ * simply involves marking all the nodes in the LEB being garbage-collected as
+ * dirty.  The dirty nodes are written next commit, after which the LEB is free
+ * to be reused.
+ *
+ * This function returns %0 on success and a negative error code on failure.
+ */
+static int make_node_dirty(struct ubifs_info *c, int node_type, int node_num,
+			   int lnum, int offs)
+{
+	switch (node_type) {
+	case UBIFS_LPT_NNODE:
+		return make_nnode_dirty(c, node_num, lnum, offs);
+	case UBIFS_LPT_PNODE:
+		return make_pnode_dirty(c, node_num, lnum, offs);
+	case UBIFS_LPT_LTAB:
+		return make_ltab_dirty(c, lnum, offs);
+	case UBIFS_LPT_LSAVE:
+		return make_lsave_dirty(c, lnum, offs);
+	}
+	return -EINVAL;
+}
+
+/**
+ * get_lpt_node_len - return the length of a node based on its type.
+ * @c: UBIFS file-system description object
+ * @node_type: LPT node type
+ */
+static int get_lpt_node_len(struct ubifs_info *c, int node_type)
+{
+	switch (node_type) {
+	case UBIFS_LPT_NNODE:
+		return c->nnode_sz;
+	case UBIFS_LPT_PNODE:
+		return c->pnode_sz;
+	case UBIFS_LPT_LTAB:
+		return c->ltab_sz;
+	case UBIFS_LPT_LSAVE:
+		return c->lsave_sz;
+	}
+	return 0;
+}
+
+/**
+ * get_pad_len - return the length of padding in a buffer.
+ * @c: UBIFS file-system description object
+ * @buf: buffer
+ * @len: length of buffer
+ */
+static int get_pad_len(struct ubifs_info *c, uint8_t *buf, int len)
+{
+	int offs, pad_len;
+
+	if (c->min_io_size == 1)
+		return 0;
+	offs = c->leb_size - len;
+	pad_len = ALIGN(offs, c->min_io_size) - offs;
+	return pad_len;
+}
+
+/**
+ * get_lpt_node_type - return type (and node number) of a node in a buffer.
+ * @c: UBIFS file-system description object
+ * @buf: buffer
+ * @node_num: node number is returned here
+ */
+static int get_lpt_node_type(struct ubifs_info *c, uint8_t *buf, int *node_num)
+{
+	uint8_t *addr = buf + UBIFS_LPT_CRC_BYTES;
+	int pos = 0, node_type;
+
+	node_type = ubifs_unpack_bits(&addr, &pos, UBIFS_LPT_TYPE_BITS);
+	*node_num = ubifs_unpack_bits(&addr, &pos, c->pcnt_bits);
+	return node_type;
+}
+
+/**
+ * is_a_node - determine if a buffer contains a node.
+ * @c: UBIFS file-system description object
+ * @buf: buffer
+ * @len: length of buffer
+ *
+ * This function returns %1 if the buffer contains a node or %0 if it does not.
+ */
+static int is_a_node(struct ubifs_info *c, uint8_t *buf, int len)
+{
+	uint8_t *addr = buf + UBIFS_LPT_CRC_BYTES;
+	int pos = 0, node_type, node_len;
+	uint16_t crc, calc_crc;
+
+	node_type = ubifs_unpack_bits(&addr, &pos, UBIFS_LPT_TYPE_BITS);
+	if (node_type == UBIFS_LPT_NOT_A_NODE)
+		return 0;
+	node_len = get_lpt_node_len(c, node_type);
+	if (!node_len || node_len > len)
+		return 0;
+	pos = 0;
+	addr = buf;
+	crc = ubifs_unpack_bits(&addr, &pos, UBIFS_LPT_CRC_BITS);
+	calc_crc = crc16(-1, buf + UBIFS_LPT_CRC_BYTES,
+			 node_len - UBIFS_LPT_CRC_BYTES);
+	if (crc != calc_crc)
+		return 0;
+	return 1;
+}
+
+
+/**
+ * lpt_gc_lnum - garbage collect a LPT LEB.
+ * @c: UBIFS file-system description object
+ * @lnum: LEB number to garbage collect
+ *
+ * LPT garbage collection is used only for the "big" LPT model
+ * (c->big_lpt == 1).  Garbage collection simply involves marking all the nodes
+ * in the LEB being garbage-collected as dirty.  The dirty nodes are written
+ * next commit, after which the LEB is free to be reused.
+ *
+ * This function returns %0 on success and a negative error code on failure.
+ */
+static int lpt_gc_lnum(struct ubifs_info *c, int lnum)
+{
+	int err, len = c->leb_size, node_type, node_num, node_len, offs;
+	void *buf = c->lpt_buf;
+
+	dbg_lp("LEB %d", lnum);
+	err = ubi_read(c->ubi, lnum, buf, 0, c->leb_size);
+	if (err) {
+		ubifs_err("cannot read LEB %d, error %d", lnum, err);
+		return err;
+	}
+	while (1) {
+		if (!is_a_node(c, buf, len)) {
+			int pad_len;
+
+			pad_len = get_pad_len(c, buf, len);
+			if (pad_len) {
+				buf += pad_len;
+				len -= pad_len;
+				continue;
+			}
+			return 0;
+		}
+		node_type = get_lpt_node_type(c, buf, &node_num);
+		node_len = get_lpt_node_len(c, node_type);
+		offs = c->leb_size - len;
+		ubifs_assert(node_len != 0);
+		mutex_lock(&c->lp_mutex);
+		err = make_node_dirty(c, node_type, node_num, lnum, offs);
+		mutex_unlock(&c->lp_mutex);
+		if (err)
+			return err;
+		buf += node_len;
+		len -= node_len;
+	}
+	return 0;
+}
+
+/**
+ * lpt_gc - LPT garbage collection.
+ * @c: UBIFS file-system description object
+ *
+ * Select a LPT LEB for LPT garbage collection and call 'lpt_gc_lnum()'.
+ * Returns %0 on success and a negative error code on failure.
+ */
+static int lpt_gc(struct ubifs_info *c)
+{
+	int i, lnum = -1, dirty = 0;
+
+	mutex_lock(&c->lp_mutex);
+	for (i = 0; i < c->lpt_lebs; i++) {
+		ubifs_assert(!c->ltab[i].tgc);
+		if (i + c->lpt_first == c->nhead_lnum ||
+		    c->ltab[i].free + c->ltab[i].dirty == c->leb_size)
+			continue;
+		if (c->ltab[i].dirty > dirty) {
+			dirty = c->ltab[i].dirty;
+			lnum = i + c->lpt_first;
+		}
+	}
+	mutex_unlock(&c->lp_mutex);
+	if (lnum == -1)
+		return -ENOSPC;
+	return lpt_gc_lnum(c, lnum);
+}
+
+/**
+ * ubifs_lpt_start_commit - UBIFS commit starts.
+ * @c: the UBIFS file-system description object
+ *
+ * This function has to be called when UBIFS starts the commit operation.
+ * This function "freezes" all currently dirty LEB properties and does not
+ * change them anymore. Further changes are saved and tracked separately
+ * because they are not part of this commit. This function returns zero in case
+ * of success and a negative error code in case of failure.
+ */
+int ubifs_lpt_start_commit(struct ubifs_info *c)
+{
+	int err, cnt;
+
+	dbg_lp("");
+
+	mutex_lock(&c->lp_mutex);
+	err = dbg_check_ltab(c);
+	if (err)
+		goto out;
+
+	if (c->check_lpt_free) {
+		/*
+		 * We ensure there is enough free space in
+		 * ubifs_lpt_post_commit() by marking nodes dirty. That
+		 * information is lost when we unmount, so we also need
+		 * to check free space once after mounting also.
+		 */
+		c->check_lpt_free = 0;
+		while (need_write_all(c)) {
+			mutex_unlock(&c->lp_mutex);
+			err = lpt_gc(c);
+			if (err)
+				return err;
+			mutex_lock(&c->lp_mutex);
+		}
+	}
+
+	lpt_tgc_start(c);
+
+	if (!c->dirty_pn_cnt) {
+		dbg_cmt("no cnodes to commit");
+		err = 0;
+		goto out;
+	}
+
+	if (!c->big_lpt && need_write_all(c)) {
+		/* If needed, write everything */
+		err = make_tree_dirty(c);
+		if (err)
+			goto out;
+		lpt_tgc_start(c);
+	}
+
+	if (c->big_lpt)
+		populate_lsave(c);
+
+	cnt = get_cnodes_to_commit(c);
+	ubifs_assert(cnt != 0);
+
+	err = layout_cnodes(c);
+	if (err)
+		goto out;
+
+	/* Copy the LPT's own lprops for end commit to write */
+	memcpy(c->ltab_cmt, c->ltab,
+	       sizeof(struct ubifs_lpt_lprops) * c->lpt_lebs);
+	c->lpt_drty_flgs &= ~(LTAB_DIRTY | LSAVE_DIRTY);
+
+out:
+	mutex_unlock(&c->lp_mutex);
+	return err;
+}
+
+/**
+ * free_obsolete_cnodes - free obsolete cnodes for commit end.
+ * @c: UBIFS file-system description object
+ */
+static void free_obsolete_cnodes(struct ubifs_info *c)
+{
+	struct ubifs_cnode *cnode, *cnext;
+
+	cnext = c->lpt_cnext;
+	if (!cnext)
+		return;
+	do {
+		cnode = cnext;
+		cnext = cnode->cnext;
+		if (test_bit(OBSOLETE_CNODE, &cnode->flags))
+			kfree(cnode);
+		else
+			cnode->cnext = NULL;
+	} while (cnext != c->lpt_cnext);
+	c->lpt_cnext = NULL;
+}
+
+/**
+ * ubifs_lpt_end_commit - finish the commit operation.
+ * @c: the UBIFS file-system description object
+ *
+ * This function has to be called when the commit operation finishes. It
+ * flushes the changes which were "frozen" by 'ubifs_lprops_start_commit()' to
+ * the media. Returns zero in case of success and a negative error code in case
+ * of failure.
+ */
+int ubifs_lpt_end_commit(struct ubifs_info *c)
+{
+	int err;
+
+	dbg_lp("");
+
+	if (!c->lpt_cnext)
+		return 0;
+
+	err = write_cnodes(c);
+	if (err)
+		return err;
+
+	mutex_lock(&c->lp_mutex);
+	free_obsolete_cnodes(c);
+	mutex_unlock(&c->lp_mutex);
+
+	return 0;
+}
+
+/**
+ * ubifs_lpt_post_commit - post commit LPT trivial GC and LPT GC.
+ * @c: UBIFS file-system description object
+ *
+ * LPT trivial GC is completed after a commit. Also LPT GC is done after a
+ * commit for the "big" LPT model.
+ */
+int ubifs_lpt_post_commit(struct ubifs_info *c)
+{
+	int err;
+
+	mutex_lock(&c->lp_mutex);
+	err = lpt_tgc_end(c);
+	if (err)
+		goto out;
+	if (c->big_lpt)
+		while (need_write_all(c)) {
+			mutex_unlock(&c->lp_mutex);
+			err = lpt_gc(c);
+			if (err)
+				return err;
+			mutex_lock(&c->lp_mutex);
+		}
+out:
+	mutex_unlock(&c->lp_mutex);
+	return err;
+}
+
+/**
+ * first_nnode - find the first nnode in memory.
+ * @c: UBIFS file-system description object
+ * @hght: height of tree where nnode found is returned here
+ *
+ * This function returns a pointer to the nnode found or %NULL if no nnode is
+ * found. This function is a helper to 'ubifs_lpt_free()'.
+ */
+static struct ubifs_nnode *first_nnode(struct ubifs_info *c, int *hght)
+{
+	struct ubifs_nnode *nnode;
+	int h, i, found;
+
+	nnode = c->nroot;
+	*hght = 0;
+	if (!nnode)
+		return NULL;
+	for (h = 1; h < c->lpt_hght; h++) {
+		found = 0;
+		for (i = 0; i < UBIFS_LPT_FANOUT; i++) {
+			if (nnode->nbranch[i].nnode) {
+				found = 1;
+				nnode = nnode->nbranch[i].nnode;
+				*hght = h;
+				break;
+			}
+		}
+		if (!found)
+			break;
+	}
+	return nnode;
+}
+
+/**
+ * next_nnode - find the next nnode in memory.
+ * @c: UBIFS file-system description object
+ * @nnode: nnode from which to start.
+ * @hght: height of tree where nnode is, is passed and returned here
+ *
+ * This function returns a pointer to the nnode found or %NULL if no nnode is
+ * found. This function is a helper to 'ubifs_lpt_free()'.
+ */
+static struct ubifs_nnode *next_nnode(struct ubifs_info *c,
+				      struct ubifs_nnode *nnode, int *hght)
+{
+	struct ubifs_nnode *parent;
+	int iip, h, i, found;
+
+	parent = nnode->parent;
+	if (!parent)
+		return NULL;
+	if (nnode->iip == UBIFS_LPT_FANOUT - 1) {
+		*hght -= 1;
+		return parent;
+	}
+	for (iip = nnode->iip + 1; iip < UBIFS_LPT_FANOUT; iip++) {
+		nnode = parent->nbranch[iip].nnode;
+		if (nnode)
+			break;
+	}
+	if (!nnode) {
+		*hght -= 1;
+		return parent;
+	}
+	for (h = *hght + 1; h < c->lpt_hght; h++) {
+		found = 0;
+		for (i = 0; i < UBIFS_LPT_FANOUT; i++) {
+			if (nnode->nbranch[i].nnode) {
+				found = 1;
+				nnode = nnode->nbranch[i].nnode;
+				*hght = h;
+				break;
+			}
+		}
+		if (!found)
+			break;
+	}
+	return nnode;
+}
+
+/**
+ * ubifs_lpt_free - free resources owned by the LPT.
+ * @c: UBIFS file-system description object
+ * @wr_only: free only resources used for writing
+ */
+void ubifs_lpt_free(struct ubifs_info *c, int wr_only)
+{
+	struct ubifs_nnode *nnode;
+	int i, hght;
+
+	/* Free write-only things first */
+
+	free_obsolete_cnodes(c); /* Leftover from a failed commit */
+
+	vfree(c->ltab_cmt);
+	c->ltab_cmt = NULL;
+	vfree(c->lpt_buf);
+	c->lpt_buf = NULL;
+	kfree(c->lsave);
+	c->lsave = NULL;
+
+	if (wr_only)
+		return;
+
+	/* Now free the rest */
+
+	nnode = first_nnode(c, &hght);
+	while (nnode) {
+		for (i = 0; i < UBIFS_LPT_FANOUT; i++)
+			kfree(nnode->nbranch[i].nnode);
+		nnode = next_nnode(c, nnode, &hght);
+	}
+	for (i = 0; i < LPROPS_HEAP_CNT; i++)
+		kfree(c->lpt_heap[i].arr);
+	kfree(c->dirty_idx.arr);
+	kfree(c->nroot);
+	vfree(c->ltab);
+	kfree(c->lpt_nod_buf);
+}
+
+#ifdef CONFIG_UBIFS_FS_DEBUG
+
+/**
+ * dbg_is_all_ff - determine if a buffer contains only 0xff bytes.
+ * @buf: buffer
+ * @len: buffer length
+ */
+static int dbg_is_all_ff(uint8_t *buf, int len)
+{
+	int i;
+
+	for (i = 0; i < len; i++)
+		if (buf[i] != 0xff)
+			return 0;
+	return 1;
+}
+
+/**
+ * dbg_is_nnode_dirty - determine if a nnode is dirty.
+ * @c: the UBIFS file-system description object
+ * @lnum: LEB number where nnode was written
+ * @offs: offset where nnode was written
+ */
+static int dbg_is_nnode_dirty(struct ubifs_info *c, int lnum, int offs)
+{
+	struct ubifs_nnode *nnode;
+	int hght;
+
+	/* Entire tree is in memory so first_nnode / next_nnode are ok */
+	nnode = first_nnode(c, &hght);
+	for (; nnode; nnode = next_nnode(c, nnode, &hght)) {
+		struct ubifs_nbranch *branch;
+
+		cond_resched();
+		if (nnode->parent) {
+			branch = &nnode->parent->nbranch[nnode->iip];
+			if (branch->lnum != lnum || branch->offs != offs)
+				continue;
+			if (test_bit(DIRTY_CNODE, &nnode->flags))
+				return 1;
+			return 0;
+		} else {
+			if (c->lpt_lnum != lnum || c->lpt_offs != offs)
+				continue;
+			if (test_bit(DIRTY_CNODE, &nnode->flags))
+				return 1;
+			return 0;
+		}
+	}
+	return 1;
+}
+
+/**
+ * dbg_is_pnode_dirty - determine if a pnode is dirty.
+ * @c: the UBIFS file-system description object
+ * @lnum: LEB number where pnode was written
+ * @offs: offset where pnode was written
+ */
+static int dbg_is_pnode_dirty(struct ubifs_info *c, int lnum, int offs)
+{
+	int i, cnt;
+
+	cnt = DIV_ROUND_UP(c->main_lebs, UBIFS_LPT_FANOUT);
+	for (i = 0; i < cnt; i++) {
+		struct ubifs_pnode *pnode;
+		struct ubifs_nbranch *branch;
+
+		cond_resched();
+		pnode = pnode_lookup(c, i);
+		if (IS_ERR(pnode))
+			return PTR_ERR(pnode);
+		branch = &pnode->parent->nbranch[pnode->iip];
+		if (branch->lnum != lnum || branch->offs != offs)
+			continue;
+		if (test_bit(DIRTY_CNODE, &pnode->flags))
+			return 1;
+		return 0;
+	}
+	return 1;
+}
+
+/**
+ * dbg_is_ltab_dirty - determine if a ltab node is dirty.
+ * @c: the UBIFS file-system description object
+ * @lnum: LEB number where ltab node was written
+ * @offs: offset where ltab node was written
+ */
+static int dbg_is_ltab_dirty(struct ubifs_info *c, int lnum, int offs)
+{
+	if (lnum != c->ltab_lnum || offs != c->ltab_offs)
+		return 1;
+	return (c->lpt_drty_flgs & LTAB_DIRTY) != 0;
+}
+
+/**
+ * dbg_is_lsave_dirty - determine if a lsave node is dirty.
+ * @c: the UBIFS file-system description object
+ * @lnum: LEB number where lsave node was written
+ * @offs: offset where lsave node was written
+ */
+static int dbg_is_lsave_dirty(struct ubifs_info *c, int lnum, int offs)
+{
+	if (lnum != c->lsave_lnum || offs != c->lsave_offs)
+		return 1;
+	return (c->lpt_drty_flgs & LSAVE_DIRTY) != 0;
+}
+
+/**
+ * dbg_is_node_dirty - determine if a node is dirty.
+ * @c: the UBIFS file-system description object
+ * @node_type: node type
+ * @lnum: LEB number where node was written
+ * @offs: offset where node was written
+ */
+static int dbg_is_node_dirty(struct ubifs_info *c, int node_type, int lnum,
+			     int offs)
+{
+	switch (node_type) {
+	case UBIFS_LPT_NNODE:
+		return dbg_is_nnode_dirty(c, lnum, offs);
+	case UBIFS_LPT_PNODE:
+		return dbg_is_pnode_dirty(c, lnum, offs);
+	case UBIFS_LPT_LTAB:
+		return dbg_is_ltab_dirty(c, lnum, offs);
+	case UBIFS_LPT_LSAVE:
+		return dbg_is_lsave_dirty(c, lnum, offs);
+	}
+	return 1;
+}
+
+/**
+ * dbg_check_ltab_lnum - check the ltab for a LPT LEB number.
+ * @c: the UBIFS file-system description object
+ * @lnum: LEB number where node was written
+ * @offs: offset where node was written
+ *
+ * This function returns %0 on success and a negative error code on failure.
+ */
+static int dbg_check_ltab_lnum(struct ubifs_info *c, int lnum)
+{
+	int err, len = c->leb_size, dirty = 0, node_type, node_num, node_len;
+	int ret;
+	void *buf = c->dbg_buf;
+
+	dbg_lp("LEB %d", lnum);
+	err = ubi_read(c->ubi, lnum, buf, 0, c->leb_size);
+	if (err) {
+		dbg_msg("ubi_read failed, LEB %d, error %d", lnum, err);
+		return err;
+	}
+	while (1) {
+		if (!is_a_node(c, buf, len)) {
+			int i, pad_len;
+
+			pad_len = get_pad_len(c, buf, len);
+			if (pad_len) {
+				buf += pad_len;
+				len -= pad_len;
+				dirty += pad_len;
+				continue;
+			}
+			if (!dbg_is_all_ff(buf, len)) {
+				dbg_msg("invalid empty space in LEB %d at %d",
+					lnum, c->leb_size - len);
+				err = -EINVAL;
+			}
+			i = lnum - c->lpt_first;
+			if (len != c->ltab[i].free) {
+				dbg_msg("invalid free space in LEB %d "
+					"(free %d, expected %d)",
+					lnum, len, c->ltab[i].free);
+				err = -EINVAL;
+			}
+			if (dirty != c->ltab[i].dirty) {
+				dbg_msg("invalid dirty space in LEB %d "
+					"(dirty %d, expected %d)",
+					lnum, dirty, c->ltab[i].dirty);
+				err = -EINVAL;
+			}
+			return err;
+		}
+		node_type = get_lpt_node_type(c, buf, &node_num);
+		node_len = get_lpt_node_len(c, node_type);
+		ret = dbg_is_node_dirty(c, node_type, lnum, c->leb_size - len);
+		if (ret == 1)
+			dirty += node_len;
+		buf += node_len;
+		len -= node_len;
+	}
+}
+
+/**
+ * dbg_check_ltab - check the free and dirty space in the ltab.
+ * @c: the UBIFS file-system description object
+ *
+ * This function returns %0 on success and a negative error code on failure.
+ */
+int dbg_check_ltab(struct ubifs_info *c)
+{
+	int lnum, err, i, cnt;
+
+	if (!(ubifs_chk_flags & UBIFS_CHK_LPROPS))
+		return 0;
+
+	/* Bring the entire tree into memory */
+	cnt = DIV_ROUND_UP(c->main_lebs, UBIFS_LPT_FANOUT);
+	for (i = 0; i < cnt; i++) {
+		struct ubifs_pnode *pnode;
+
+		pnode = pnode_lookup(c, i);
+		if (IS_ERR(pnode))
+			return PTR_ERR(pnode);
+		cond_resched();
+	}
+
+	/* Check nodes */
+	err = dbg_check_lpt_nodes(c, (struct ubifs_cnode *)c->nroot, 0, 0);
+	if (err)
+		return err;
+
+	/* Check each LEB */
+	for (lnum = c->lpt_first; lnum <= c->lpt_last; lnum++) {
+		err = dbg_check_ltab_lnum(c, lnum);
+		if (err) {
+			dbg_err("failed at LEB %d", lnum);
+			return err;
+		}
+	}
+
+	dbg_lp("succeeded");
+	return 0;
+}
+
+#endif /* CONFIG_UBIFS_FS_DEBUG */
diff --git a/fs/ubifs/master.c b/fs/ubifs/master.c
new file mode 100644
index 00000000000..71d5493bf56
--- /dev/null
+++ b/fs/ubifs/master.c
@@ -0,0 +1,387 @@
+/*
+ * This file is part of UBIFS.
+ *
+ * Copyright (C) 2006-2008 Nokia Corporation.
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 as published by
+ * the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
+ * more details.
+ *
+ * You should have received a copy of the GNU General Public License along with
+ * this program; if not, write to the Free Software Foundation, Inc., 51
+ * Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
+ *
+ * Authors: Artem Bityutskiy (Битюцкий Артём)
+ *          Adrian Hunter
+ */
+
+/* This file implements reading and writing the master node */
+
+#include "ubifs.h"
+
+/**
+ * scan_for_master - search the valid master node.
+ * @c: UBIFS file-system description object
+ *
+ * This function scans the master node LEBs and search for the latest master
+ * node. Returns zero in case of success and a negative error code in case of
+ * failure.
+ */
+static int scan_for_master(struct ubifs_info *c)
+{
+	struct ubifs_scan_leb *sleb;
+	struct ubifs_scan_node *snod;
+	int lnum, offs = 0, nodes_cnt;
+
+	lnum = UBIFS_MST_LNUM;
+
+	sleb = ubifs_scan(c, lnum, 0, c->sbuf);
+	if (IS_ERR(sleb))
+		return PTR_ERR(sleb);
+	nodes_cnt = sleb->nodes_cnt;
+	if (nodes_cnt > 0) {
+		snod = list_entry(sleb->nodes.prev, struct ubifs_scan_node,
+				  list);
+		if (snod->type != UBIFS_MST_NODE)
+			goto out;
+		memcpy(c->mst_node, snod->node, snod->len);
+		offs = snod->offs;
+	}
+	ubifs_scan_destroy(sleb);
+
+	lnum += 1;
+
+	sleb = ubifs_scan(c, lnum, 0, c->sbuf);
+	if (IS_ERR(sleb))
+		return PTR_ERR(sleb);
+	if (sleb->nodes_cnt != nodes_cnt)
+		goto out;
+	if (!sleb->nodes_cnt)
+		goto out;
+	snod = list_entry(sleb->nodes.prev, struct ubifs_scan_node, list);
+	if (snod->type != UBIFS_MST_NODE)
+		goto out;
+	if (snod->offs != offs)
+		goto out;
+	if (memcmp((void *)c->mst_node + UBIFS_CH_SZ,
+		   (void *)snod->node + UBIFS_CH_SZ,
+		   UBIFS_MST_NODE_SZ - UBIFS_CH_SZ))
+		goto out;
+	c->mst_offs = offs;
+	ubifs_scan_destroy(sleb);
+	return 0;
+
+out:
+	ubifs_scan_destroy(sleb);
+	return -EINVAL;
+}
+
+/**
+ * validate_master - validate master node.
+ * @c: UBIFS file-system description object
+ *
+ * This function validates data which was read from master node. Returns zero
+ * if the data is all right and %-EINVAL if not.
+ */
+static int validate_master(const struct ubifs_info *c)
+{
+	long long main_sz;
+	int err;
+
+	if (c->max_sqnum >= SQNUM_WATERMARK) {
+		err = 1;
+		goto out;
+	}
+
+	if (c->cmt_no >= c->max_sqnum) {
+		err = 2;
+		goto out;
+	}
+
+	if (c->highest_inum >= INUM_WATERMARK) {
+		err = 3;
+		goto out;
+	}
+
+	if (c->lhead_lnum < UBIFS_LOG_LNUM ||
+	    c->lhead_lnum >= UBIFS_LOG_LNUM + c->log_lebs ||
+	    c->lhead_offs < 0 || c->lhead_offs >= c->leb_size ||
+	    c->lhead_offs & (c->min_io_size - 1)) {
+		err = 4;
+		goto out;
+	}
+
+	if (c->zroot.lnum >= c->leb_cnt || c->zroot.lnum < c->main_first ||
+	    c->zroot.offs >= c->leb_size || c->zroot.offs & 7) {
+		err = 5;
+		goto out;
+	}
+
+	if (c->zroot.len < c->ranges[UBIFS_IDX_NODE].min_len ||
+	    c->zroot.len > c->ranges[UBIFS_IDX_NODE].max_len) {
+		err = 6;
+		goto out;
+	}
+
+	if (c->gc_lnum >= c->leb_cnt || c->gc_lnum < c->main_first) {
+		err = 7;
+		goto out;
+	}
+
+	if (c->ihead_lnum >= c->leb_cnt || c->ihead_lnum < c->main_first ||
+	    c->ihead_offs % c->min_io_size || c->ihead_offs < 0 ||
+	    c->ihead_offs > c->leb_size || c->ihead_offs & 7) {
+		err = 8;
+		goto out;
+	}
+
+	main_sz = (long long)c->main_lebs * c->leb_size;
+	if (c->old_idx_sz & 7 || c->old_idx_sz >= main_sz) {
+		err = 9;
+		goto out;
+	}
+
+	if (c->lpt_lnum < c->lpt_first || c->lpt_lnum > c->lpt_last ||
+	    c->lpt_offs < 0 || c->lpt_offs + c->nnode_sz > c->leb_size) {
+		err = 10;
+		goto out;
+	}
+
+	if (c->nhead_lnum < c->lpt_first || c->nhead_lnum > c->lpt_last ||
+	    c->nhead_offs < 0 || c->nhead_offs % c->min_io_size ||
+	    c->nhead_offs > c->leb_size) {
+		err = 11;
+		goto out;
+	}
+
+	if (c->ltab_lnum < c->lpt_first || c->ltab_lnum > c->lpt_last ||
+	    c->ltab_offs < 0 ||
+	    c->ltab_offs + c->ltab_sz > c->leb_size) {
+		err = 12;
+		goto out;
+	}
+
+	if (c->big_lpt && (c->lsave_lnum < c->lpt_first ||
+	    c->lsave_lnum > c->lpt_last || c->lsave_offs < 0 ||
+	    c->lsave_offs + c->lsave_sz > c->leb_size)) {
+		err = 13;
+		goto out;
+	}
+
+	if (c->lscan_lnum < c->main_first || c->lscan_lnum >= c->leb_cnt) {
+		err = 14;
+		goto out;
+	}
+
+	if (c->lst.empty_lebs < 0 || c->lst.empty_lebs > c->main_lebs - 2) {
+		err = 15;
+		goto out;
+	}
+
+	if (c->lst.idx_lebs < 0 || c->lst.idx_lebs > c->main_lebs - 1) {
+		err = 16;
+		goto out;
+	}
+
+	if (c->lst.total_free < 0 || c->lst.total_free > main_sz ||
+	    c->lst.total_free & 7) {
+		err = 17;
+		goto out;
+	}
+
+	if (c->lst.total_dirty < 0 || (c->lst.total_dirty & 7)) {
+		err = 18;
+		goto out;
+	}
+
+	if (c->lst.total_used < 0 || (c->lst.total_used & 7)) {
+		err = 19;
+		goto out;
+	}
+
+	if (c->lst.total_free + c->lst.total_dirty +
+	    c->lst.total_used > main_sz) {
+		err = 20;
+		goto out;
+	}
+
+	if (c->lst.total_dead + c->lst.total_dark +
+	    c->lst.total_used + c->old_idx_sz > main_sz) {
+		err = 21;
+		goto out;
+	}
+
+	if (c->lst.total_dead < 0 ||
+	    c->lst.total_dead > c->lst.total_free + c->lst.total_dirty ||
+	    c->lst.total_dead & 7) {
+		err = 22;
+		goto out;
+	}
+
+	if (c->lst.total_dark < 0 ||
+	    c->lst.total_dark > c->lst.total_free + c->lst.total_dirty ||
+	    c->lst.total_dark & 7) {
+		err = 23;
+		goto out;
+	}
+
+	return 0;
+
+out:
+	ubifs_err("bad master node at offset %d error %d", c->mst_offs, err);
+	dbg_dump_node(c, c->mst_node);
+	return -EINVAL;
+}
+
+/**
+ * ubifs_read_master - read master node.
+ * @c: UBIFS file-system description object
+ *
+ * This function finds and reads the master node during file-system mount. If
+ * the flash is empty, it creates default master node as well. Returns zero in
+ * case of success and a negative error code in case of failure.
+ */
+int ubifs_read_master(struct ubifs_info *c)
+{
+	int err, old_leb_cnt;
+
+	c->mst_node = kzalloc(c->mst_node_alsz, GFP_KERNEL);
+	if (!c->mst_node)
+		return -ENOMEM;
+
+	err = scan_for_master(c);
+	if (err) {
+		err = ubifs_recover_master_node(c);
+		if (err)
+			/*
+			 * Note, we do not free 'c->mst_node' here because the
+			 * unmount routine will take care of this.
+			 */
+			return err;
+	}
+
+	/* Make sure that the recovery flag is clear */
+	c->mst_node->flags &= cpu_to_le32(~UBIFS_MST_RCVRY);
+
+	c->max_sqnum       = le64_to_cpu(c->mst_node->ch.sqnum);
+	c->highest_inum    = le64_to_cpu(c->mst_node->highest_inum);
+	c->cmt_no          = le64_to_cpu(c->mst_node->cmt_no);
+	c->zroot.lnum      = le32_to_cpu(c->mst_node->root_lnum);
+	c->zroot.offs      = le32_to_cpu(c->mst_node->root_offs);
+	c->zroot.len       = le32_to_cpu(c->mst_node->root_len);
+	c->lhead_lnum      = le32_to_cpu(c->mst_node->log_lnum);
+	c->gc_lnum         = le32_to_cpu(c->mst_node->gc_lnum);
+	c->ihead_lnum      = le32_to_cpu(c->mst_node->ihead_lnum);
+	c->ihead_offs      = le32_to_cpu(c->mst_node->ihead_offs);
+	c->old_idx_sz      = le64_to_cpu(c->mst_node->index_size);
+	c->lpt_lnum        = le32_to_cpu(c->mst_node->lpt_lnum);
+	c->lpt_offs        = le32_to_cpu(c->mst_node->lpt_offs);
+	c->nhead_lnum      = le32_to_cpu(c->mst_node->nhead_lnum);
+	c->nhead_offs      = le32_to_cpu(c->mst_node->nhead_offs);
+	c->ltab_lnum       = le32_to_cpu(c->mst_node->ltab_lnum);
+	c->ltab_offs       = le32_to_cpu(c->mst_node->ltab_offs);
+	c->lsave_lnum      = le32_to_cpu(c->mst_node->lsave_lnum);
+	c->lsave_offs      = le32_to_cpu(c->mst_node->lsave_offs);
+	c->lscan_lnum      = le32_to_cpu(c->mst_node->lscan_lnum);
+	c->lst.empty_lebs  = le32_to_cpu(c->mst_node->empty_lebs);
+	c->lst.idx_lebs    = le32_to_cpu(c->mst_node->idx_lebs);
+	old_leb_cnt        = le32_to_cpu(c->mst_node->leb_cnt);
+	c->lst.total_free  = le64_to_cpu(c->mst_node->total_free);
+	c->lst.total_dirty = le64_to_cpu(c->mst_node->total_dirty);
+	c->lst.total_used  = le64_to_cpu(c->mst_node->total_used);
+	c->lst.total_dead  = le64_to_cpu(c->mst_node->total_dead);
+	c->lst.total_dark  = le64_to_cpu(c->mst_node->total_dark);
+
+	c->calc_idx_sz = c->old_idx_sz;
+
+	if (c->mst_node->flags & cpu_to_le32(UBIFS_MST_NO_ORPHS))
+		c->no_orphs = 1;
+
+	if (old_leb_cnt != c->leb_cnt) {
+		/* The file system has been resized */
+		int growth = c->leb_cnt - old_leb_cnt;
+
+		if (c->leb_cnt < old_leb_cnt ||
+		    c->leb_cnt < UBIFS_MIN_LEB_CNT) {
+			ubifs_err("bad leb_cnt on master node");
+			dbg_dump_node(c, c->mst_node);
+			return -EINVAL;
+		}
+
+		dbg_mnt("Auto resizing (master) from %d LEBs to %d LEBs",
+			old_leb_cnt, c->leb_cnt);
+		c->lst.empty_lebs += growth;
+		c->lst.total_free += growth * (long long)c->leb_size;
+		c->lst.total_dark += growth * (long long)c->dark_wm;
+
+		/*
+		 * Reflect changes back onto the master node. N.B. the master
+		 * node gets written immediately whenever mounting (or
+		 * remounting) in read-write mode, so we do not need to write it
+		 * here.
+		 */
+		c->mst_node->leb_cnt = cpu_to_le32(c->leb_cnt);
+		c->mst_node->empty_lebs = cpu_to_le32(c->lst.empty_lebs);
+		c->mst_node->total_free = cpu_to_le64(c->lst.total_free);
+		c->mst_node->total_dark = cpu_to_le64(c->lst.total_dark);
+	}
+
+	err = validate_master(c);
+	if (err)
+		return err;
+
+	err = dbg_old_index_check_init(c, &c->zroot);
+
+	return err;
+}
+
+/**
+ * ubifs_write_master - write master node.
+ * @c: UBIFS file-system description object
+ *
+ * This function writes the master node. The caller has to take the
+ * @c->mst_mutex lock before calling this function. Returns zero in case of
+ * success and a negative error code in case of failure. The master node is
+ * written twice to enable recovery.
+ */
+int ubifs_write_master(struct ubifs_info *c)
+{
+	int err, lnum, offs, len;
+
+	if (c->ro_media)
+		return -EINVAL;
+
+	lnum = UBIFS_MST_LNUM;
+	offs = c->mst_offs + c->mst_node_alsz;
+	len = UBIFS_MST_NODE_SZ;
+
+	if (offs + UBIFS_MST_NODE_SZ > c->leb_size) {
+		err = ubifs_leb_unmap(c, lnum);
+		if (err)
+			return err;
+		offs = 0;
+	}
+
+	c->mst_offs = offs;
+	c->mst_node->highest_inum = cpu_to_le64(c->highest_inum);
+
+	err = ubifs_write_node(c, c->mst_node, len, lnum, offs, UBI_SHORTTERM);
+	if (err)
+		return err;
+
+	lnum += 1;
+
+	if (offs == 0) {
+		err = ubifs_leb_unmap(c, lnum);
+		if (err)
+			return err;
+	}
+	err = ubifs_write_node(c, c->mst_node, len, lnum, offs, UBI_SHORTTERM);
+
+	return err;
+}
diff --git a/fs/ubifs/misc.h b/fs/ubifs/misc.h
new file mode 100644
index 00000000000..4beccfc256d
--- /dev/null
+++ b/fs/ubifs/misc.h
@@ -0,0 +1,342 @@
+/*
+ * This file is part of UBIFS.
+ *
+ * Copyright (C) 2006-2008 Nokia Corporation
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 as published by
+ * the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
+ * more details.
+ *
+ * You should have received a copy of the GNU General Public License along with
+ * this program; if not, write to the Free Software Foundation, Inc., 51
+ * Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
+ *
+ * Authors: Artem Bityutskiy (Битюцкий Артём)
+ *          Adrian Hunter
+ */
+
+/*
+ * This file contains miscellaneous helper functions.
+ */
+
+#ifndef __UBIFS_MISC_H__
+#define __UBIFS_MISC_H__
+
+/**
+ * ubifs_zn_dirty - check if znode is dirty.
+ * @znode: znode to check
+ *
+ * This helper function returns %1 if @znode is dirty and %0 otherwise.
+ */
+static inline int ubifs_zn_dirty(const struct ubifs_znode *znode)
+{
+	return !!test_bit(DIRTY_ZNODE, &znode->flags);
+}
+
+/**
+ * ubifs_wake_up_bgt - wake up background thread.
+ * @c: UBIFS file-system description object
+ */
+static inline void ubifs_wake_up_bgt(struct ubifs_info *c)
+{
+	if (c->bgt && !c->need_bgt) {
+		c->need_bgt = 1;
+		wake_up_process(c->bgt);
+	}
+}
+
+/**
+ * ubifs_tnc_find_child - find next child in znode.
+ * @znode: znode to search at
+ * @start: the zbranch index to start at
+ *
+ * This helper function looks for znode child starting at index @start. Returns
+ * the child or %NULL if no children were found.
+ */
+static inline struct ubifs_znode *
+ubifs_tnc_find_child(struct ubifs_znode *znode, int start)
+{
+	while (start < znode->child_cnt) {
+		if (znode->zbranch[start].znode)
+			return znode->zbranch[start].znode;
+		start += 1;
+	}
+
+	return NULL;
+}
+
+/**
+ * ubifs_inode - get UBIFS inode information by VFS 'struct inode' object.
+ * @inode: the VFS 'struct inode' pointer
+ */
+static inline struct ubifs_inode *ubifs_inode(const struct inode *inode)
+{
+	return container_of(inode, struct ubifs_inode, vfs_inode);
+}
+
+/**
+ * ubifs_ro_mode - switch UBIFS to read read-only mode.
+ * @c: UBIFS file-system description object
+ * @err: error code which is the reason of switching to R/O mode
+ */
+static inline void ubifs_ro_mode(struct ubifs_info *c, int err)
+{
+	if (!c->ro_media) {
+		c->ro_media = 1;
+		ubifs_warn("switched to read-only mode, error %d", err);
+		dbg_dump_stack();
+	}
+}
+
+/**
+ * ubifs_compr_present - check if compressor was compiled in.
+ * @compr_type: compressor type to check
+ *
+ * This function returns %1 of compressor of type @compr_type is present, and
+ * %0 if not.
+ */
+static inline int ubifs_compr_present(int compr_type)
+{
+	ubifs_assert(compr_type >= 0 && compr_type < UBIFS_COMPR_TYPES_CNT);
+	return !!ubifs_compressors[compr_type]->capi_name;
+}
+
+/**
+ * ubifs_compr_name - get compressor name string by its type.
+ * @compr_type: compressor type
+ *
+ * This function returns compressor type string.
+ */
+static inline const char *ubifs_compr_name(int compr_type)
+{
+	ubifs_assert(compr_type >= 0 && compr_type < UBIFS_COMPR_TYPES_CNT);
+	return ubifs_compressors[compr_type]->name;
+}
+
+/**
+ * ubifs_wbuf_sync - synchronize write-buffer.
+ * @wbuf: write-buffer to synchronize
+ *
+ * This is the same as as 'ubifs_wbuf_sync_nolock()' but it does not assume
+ * that the write-buffer is already locked.
+ */
+static inline int ubifs_wbuf_sync(struct ubifs_wbuf *wbuf)
+{
+	int err;
+
+	mutex_lock_nested(&wbuf->io_mutex, wbuf->jhead);
+	err = ubifs_wbuf_sync_nolock(wbuf);
+	mutex_unlock(&wbuf->io_mutex);
+	return err;
+}
+
+/**
+ * ubifs_leb_unmap - unmap an LEB.
+ * @c: UBIFS file-system description object
+ * @lnum: LEB number to unmap
+ *
+ * This function returns %0 on success and a negative error code on failure.
+ */
+static inline int ubifs_leb_unmap(const struct ubifs_info *c, int lnum)
+{
+	int err;
+
+	if (c->ro_media)
+		return -EROFS;
+	err = ubi_leb_unmap(c->ubi, lnum);
+	if (err) {
+		ubifs_err("unmap LEB %d failed, error %d", lnum, err);
+		return err;
+	}
+
+	return 0;
+}
+
+/**
+ * ubifs_leb_write - write to a LEB.
+ * @c: UBIFS file-system description object
+ * @lnum: LEB number to write
+ * @buf: buffer to write from
+ * @offs: offset within LEB to write to
+ * @len: length to write
+ * @dtype: data type
+ *
+ * This function returns %0 on success and a negative error code on failure.
+ */
+static inline int ubifs_leb_write(const struct ubifs_info *c, int lnum,
+				  const void *buf, int offs, int len, int dtype)
+{
+	int err;
+
+	if (c->ro_media)
+		return -EROFS;
+	err = ubi_leb_write(c->ubi, lnum, buf, offs, len, dtype);
+	if (err) {
+		ubifs_err("writing %d bytes at %d:%d, error %d",
+			  len, lnum, offs, err);
+		return err;
+	}
+
+	return 0;
+}
+
+/**
+ * ubifs_leb_change - atomic LEB change.
+ * @c: UBIFS file-system description object
+ * @lnum: LEB number to write
+ * @buf: buffer to write from
+ * @len: length to write
+ * @dtype: data type
+ *
+ * This function returns %0 on success and a negative error code on failure.
+ */
+static inline int ubifs_leb_change(const struct ubifs_info *c, int lnum,
+				   const void *buf, int len, int dtype)
+{
+	int err;
+
+	if (c->ro_media)
+		return -EROFS;
+	err = ubi_leb_change(c->ubi, lnum, buf, len, dtype);
+	if (err) {
+		ubifs_err("changing %d bytes in LEB %d, error %d",
+			  len, lnum, err);
+		return err;
+	}
+
+	return 0;
+}
+
+/**
+ * ubifs_encode_dev - encode device node IDs.
+ * @dev: UBIFS device node information
+ * @rdev: device IDs to encode
+ *
+ * This is a helper function which encodes major/minor numbers of a device node
+ * into UBIFS device node description. We use standard Linux "new" and "huge"
+ * encodings.
+ */
+static inline int ubifs_encode_dev(union ubifs_dev_desc *dev, dev_t rdev)
+{
+	if (new_valid_dev(rdev)) {
+		dev->new = cpu_to_le32(new_encode_dev(rdev));
+		return sizeof(dev->new);
+	} else {
+		dev->huge = cpu_to_le64(huge_encode_dev(rdev));
+		return sizeof(dev->huge);
+	}
+}
+
+/**
+ * ubifs_add_dirt - add dirty space to LEB properties.
+ * @c: the UBIFS file-system description object
+ * @lnum: LEB to add dirty space for
+ * @dirty: dirty space to add
+ *
+ * This is a helper function which increased amount of dirty LEB space. Returns
+ * zero in case of success and a negative error code in case of failure.
+ */
+static inline int ubifs_add_dirt(struct ubifs_info *c, int lnum, int dirty)
+{
+	return ubifs_update_one_lp(c, lnum, LPROPS_NC, dirty, 0, 0);
+}
+
+/**
+ * ubifs_return_leb - return LEB to lprops.
+ * @c: the UBIFS file-system description object
+ * @lnum: LEB to return
+ *
+ * This helper function cleans the "taken" flag of a logical eraseblock in the
+ * lprops. Returns zero in case of success and a negative error code in case of
+ * failure.
+ */
+static inline int ubifs_return_leb(struct ubifs_info *c, int lnum)
+{
+	return ubifs_change_one_lp(c, lnum, LPROPS_NC, LPROPS_NC, 0,
+				   LPROPS_TAKEN, 0);
+}
+
+/**
+ * ubifs_idx_node_sz - return index node size.
+ * @c: the UBIFS file-system description object
+ * @child_cnt: number of children of this index node
+ */
+static inline int ubifs_idx_node_sz(const struct ubifs_info *c, int child_cnt)
+{
+	return UBIFS_IDX_NODE_SZ + (UBIFS_BRANCH_SZ + c->key_len) * child_cnt;
+}
+
+/**
+ * ubifs_idx_branch - return pointer to an index branch.
+ * @c: the UBIFS file-system description object
+ * @idx: index node
+ * @bnum: branch number
+ */
+static inline
+struct ubifs_branch *ubifs_idx_branch(const struct ubifs_info *c,
+				      const struct ubifs_idx_node *idx,
+				      int bnum)
+{
+	return (struct ubifs_branch *)((void *)idx->branches +
+				       (UBIFS_BRANCH_SZ + c->key_len) * bnum);
+}
+
+/**
+ * ubifs_idx_key - return pointer to an index key.
+ * @c: the UBIFS file-system description object
+ * @idx: index node
+ */
+static inline void *ubifs_idx_key(const struct ubifs_info *c,
+				  const struct ubifs_idx_node *idx)
+{
+	return (void *)((struct ubifs_branch *)idx->branches)->key;
+}
+
+/**
+ * ubifs_reported_space - calculate reported free space.
+ * @c: the UBIFS file-system description object
+ * @free: amount of free space
+ *
+ * This function calculates amount of free space which will be reported to
+ * user-space. User-space application tend to expect that if the file-system
+ * (e.g., via the 'statfs()' call) reports that it has N bytes available, they
+ * are able to write a file of size N. UBIFS attaches node headers to each data
+ * node and it has to write indexind nodes as well. This introduces additional
+ * overhead, and UBIFS it has to report sligtly less free space to meet the
+ * above expectetion.
+ *
+ * This function assumes free space is made up of uncompressed data nodes and
+ * full index nodes (one per data node, doubled because we always allow enough
+ * space to write the index twice).
+ *
+ * Note, the calculation is pessimistic, which means that most of the time
+ * UBIFS reports less space than it actually has.
+ */
+static inline long long ubifs_reported_space(const struct ubifs_info *c,
+					     uint64_t free)
+{
+	int divisor, factor;
+
+	divisor = UBIFS_MAX_DATA_NODE_SZ + (c->max_idx_node_sz << 1);
+	factor = UBIFS_MAX_DATA_NODE_SZ - UBIFS_DATA_NODE_SZ;
+	do_div(free, divisor);
+
+	return free * factor;
+}
+
+/**
+ * ubifs_current_time - round current time to time granularity.
+ * @inode: inode
+ */
+static inline struct timespec ubifs_current_time(struct inode *inode)
+{
+	return (inode->i_sb->s_time_gran < NSEC_PER_SEC) ?
+		current_fs_time(inode->i_sb) : CURRENT_TIME_SEC;
+}
+
+#endif /* __UBIFS_MISC_H__ */
diff --git a/fs/ubifs/orphan.c b/fs/ubifs/orphan.c
new file mode 100644
index 00000000000..3afeb9242c6
--- /dev/null
+++ b/fs/ubifs/orphan.c
@@ -0,0 +1,958 @@
+/*
+ * This file is part of UBIFS.
+ *
+ * Copyright (C) 2006-2008 Nokia Corporation.
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 as published by
+ * the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
+ * more details.
+ *
+ * You should have received a copy of the GNU General Public License along with
+ * this program; if not, write to the Free Software Foundation, Inc., 51
+ * Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
+ *
+ * Author: Adrian Hunter
+ */
+
+#include "ubifs.h"
+
+/*
+ * An orphan is an inode number whose inode node has been committed to the index
+ * with a link count of zero. That happens when an open file is deleted
+ * (unlinked) and then a commit is run. In the normal course of events the inode
+ * would be deleted when the file is closed. However in the case of an unclean
+ * unmount, orphans need to be accounted for. After an unclean unmount, the
+ * orphans' inodes must be deleted which means either scanning the entire index
+ * looking for them, or keeping a list on flash somewhere. This unit implements
+ * the latter approach.
+ *
+ * The orphan area is a fixed number of LEBs situated between the LPT area and
+ * the main area. The number of orphan area LEBs is specified when the file
+ * system is created. The minimum number is 1. The size of the orphan area
+ * should be so that it can hold the maximum number of orphans that are expected
+ * to ever exist at one time.
+ *
+ * The number of orphans that can fit in a LEB is:
+ *
+ *         (c->leb_size - UBIFS_ORPH_NODE_SZ) / sizeof(__le64)
+ *
+ * For example: a 15872 byte LEB can fit 1980 orphans so 1 LEB may be enough.
+ *
+ * Orphans are accumulated in a rb-tree. When an inode's link count drops to
+ * zero, the inode number is added to the rb-tree. It is removed from the tree
+ * when the inode is deleted.  Any new orphans that are in the orphan tree when
+ * the commit is run, are written to the orphan area in 1 or more orph nodes.
+ * If the orphan area is full, it is consolidated to make space.  There is
+ * always enough space because validation prevents the user from creating more
+ * than the maximum number of orphans allowed.
+ */
+
+#ifdef CONFIG_UBIFS_FS_DEBUG
+static int dbg_check_orphans(struct ubifs_info *c);
+#else
+#define dbg_check_orphans(c) 0
+#endif
+
+/**
+ * ubifs_add_orphan - add an orphan.
+ * @c: UBIFS file-system description object
+ * @inum: orphan inode number
+ *
+ * Add an orphan. This function is called when an inodes link count drops to
+ * zero.
+ */
+int ubifs_add_orphan(struct ubifs_info *c, ino_t inum)
+{
+	struct ubifs_orphan *orphan, *o;
+	struct rb_node **p, *parent = NULL;
+
+	orphan = kzalloc(sizeof(struct ubifs_orphan), GFP_NOFS);
+	if (!orphan)
+		return -ENOMEM;
+	orphan->inum = inum;
+	orphan->new = 1;
+
+	spin_lock(&c->orphan_lock);
+	if (c->tot_orphans >= c->max_orphans) {
+		spin_unlock(&c->orphan_lock);
+		kfree(orphan);
+		return -ENFILE;
+	}
+	p = &c->orph_tree.rb_node;
+	while (*p) {
+		parent = *p;
+		o = rb_entry(parent, struct ubifs_orphan, rb);
+		if (inum < o->inum)
+			p = &(*p)->rb_left;
+		else if (inum > o->inum)
+			p = &(*p)->rb_right;
+		else {
+			dbg_err("orphaned twice");
+			spin_unlock(&c->orphan_lock);
+			kfree(orphan);
+			return 0;
+		}
+	}
+	c->tot_orphans += 1;
+	c->new_orphans += 1;
+	rb_link_node(&orphan->rb, parent, p);
+	rb_insert_color(&orphan->rb, &c->orph_tree);
+	list_add_tail(&orphan->list, &c->orph_list);
+	list_add_tail(&orphan->new_list, &c->orph_new);
+	spin_unlock(&c->orphan_lock);
+	dbg_gen("ino %lu", inum);
+	return 0;
+}
+
+/**
+ * ubifs_delete_orphan - delete an orphan.
+ * @c: UBIFS file-system description object
+ * @inum: orphan inode number
+ *
+ * Delete an orphan. This function is called when an inode is deleted.
+ */
+void ubifs_delete_orphan(struct ubifs_info *c, ino_t inum)
+{
+	struct ubifs_orphan *o;
+	struct rb_node *p;
+
+	spin_lock(&c->orphan_lock);
+	p = c->orph_tree.rb_node;
+	while (p) {
+		o = rb_entry(p, struct ubifs_orphan, rb);
+		if (inum < o->inum)
+			p = p->rb_left;
+		else if (inum > o->inum)
+			p = p->rb_right;
+		else {
+			if (o->dnext) {
+				spin_unlock(&c->orphan_lock);
+				dbg_gen("deleted twice ino %lu", inum);
+				return;
+			}
+			if (o->cnext) {
+				o->dnext = c->orph_dnext;
+				c->orph_dnext = o;
+				spin_unlock(&c->orphan_lock);
+				dbg_gen("delete later ino %lu", inum);
+				return;
+			}
+			rb_erase(p, &c->orph_tree);
+			list_del(&o->list);
+			c->tot_orphans -= 1;
+			if (o->new) {
+				list_del(&o->new_list);
+				c->new_orphans -= 1;
+			}
+			spin_unlock(&c->orphan_lock);
+			kfree(o);
+			dbg_gen("inum %lu", inum);
+			return;
+		}
+	}
+	spin_unlock(&c->orphan_lock);
+	dbg_err("missing orphan ino %lu", inum);
+	dbg_dump_stack();
+}
+
+/**
+ * ubifs_orphan_start_commit - start commit of orphans.
+ * @c: UBIFS file-system description object
+ *
+ * Start commit of orphans.
+ */
+int ubifs_orphan_start_commit(struct ubifs_info *c)
+{
+	struct ubifs_orphan *orphan, **last;
+
+	spin_lock(&c->orphan_lock);
+	last = &c->orph_cnext;
+	list_for_each_entry(orphan, &c->orph_new, new_list) {
+		ubifs_assert(orphan->new);
+		orphan->new = 0;
+		*last = orphan;
+		last = &orphan->cnext;
+	}
+	*last = orphan->cnext;
+	c->cmt_orphans = c->new_orphans;
+	c->new_orphans = 0;
+	dbg_cmt("%d orphans to commit", c->cmt_orphans);
+	INIT_LIST_HEAD(&c->orph_new);
+	if (c->tot_orphans == 0)
+		c->no_orphs = 1;
+	else
+		c->no_orphs = 0;
+	spin_unlock(&c->orphan_lock);
+	return 0;
+}
+
+/**
+ * avail_orphs - calculate available space.
+ * @c: UBIFS file-system description object
+ *
+ * This function returns the number of orphans that can be written in the
+ * available space.
+ */
+static int avail_orphs(struct ubifs_info *c)
+{
+	int avail_lebs, avail, gap;
+
+	avail_lebs = c->orph_lebs - (c->ohead_lnum - c->orph_first) - 1;
+	avail = avail_lebs *
+	       ((c->leb_size - UBIFS_ORPH_NODE_SZ) / sizeof(__le64));
+	gap = c->leb_size - c->ohead_offs;
+	if (gap >= UBIFS_ORPH_NODE_SZ + sizeof(__le64))
+		avail += (gap - UBIFS_ORPH_NODE_SZ) / sizeof(__le64);
+	return avail;
+}
+
+/**
+ * tot_avail_orphs - calculate total space.
+ * @c: UBIFS file-system description object
+ *
+ * This function returns the number of orphans that can be written in half
+ * the total space. That leaves half the space for adding new orphans.
+ */
+static int tot_avail_orphs(struct ubifs_info *c)
+{
+	int avail_lebs, avail;
+
+	avail_lebs = c->orph_lebs;
+	avail = avail_lebs *
+	       ((c->leb_size - UBIFS_ORPH_NODE_SZ) / sizeof(__le64));
+	return avail / 2;
+}
+
+/**
+ * do_write_orph_node - write a node
+ * @c: UBIFS file-system description object
+ * @len: length of node
+ * @atomic: write atomically
+ *
+ * This function writes a node to the orphan head from the orphan buffer. If
+ * %atomic is not zero, then the write is done atomically. On success, %0 is
+ * returned, otherwise a negative error code is returned.
+ */
+static int do_write_orph_node(struct ubifs_info *c, int len, int atomic)
+{
+	int err = 0;
+
+	if (atomic) {
+		ubifs_assert(c->ohead_offs == 0);
+		ubifs_prepare_node(c, c->orph_buf, len, 1);
+		len = ALIGN(len, c->min_io_size);
+		err = ubifs_leb_change(c, c->ohead_lnum, c->orph_buf, len,
+				       UBI_SHORTTERM);
+	} else {
+		if (c->ohead_offs == 0) {
+			/* Ensure LEB has been unmapped */
+			err = ubifs_leb_unmap(c, c->ohead_lnum);
+			if (err)
+				return err;
+		}
+		err = ubifs_write_node(c, c->orph_buf, len, c->ohead_lnum,
+				       c->ohead_offs, UBI_SHORTTERM);
+	}
+	return err;
+}
+
+/**
+ * write_orph_node - write an orph node
+ * @c: UBIFS file-system description object
+ * @atomic: write atomically
+ *
+ * This function builds an orph node from the cnext list and writes it to the
+ * orphan head. On success, %0 is returned, otherwise a negative error code
+ * is returned.
+ */
+static int write_orph_node(struct ubifs_info *c, int atomic)
+{
+	struct ubifs_orphan *orphan, *cnext;
+	struct ubifs_orph_node *orph;
+	int gap, err, len, cnt, i;
+
+	ubifs_assert(c->cmt_orphans > 0);
+	gap = c->leb_size - c->ohead_offs;
+	if (gap < UBIFS_ORPH_NODE_SZ + sizeof(__le64)) {
+		c->ohead_lnum += 1;
+		c->ohead_offs = 0;
+		gap = c->leb_size;
+		if (c->ohead_lnum > c->orph_last) {
+			/*
+			 * We limit the number of orphans so that this should
+			 * never happen.
+			 */
+			ubifs_err("out of space in orphan area");
+			return -EINVAL;
+		}
+	}
+	cnt = (gap - UBIFS_ORPH_NODE_SZ) / sizeof(__le64);
+	if (cnt > c->cmt_orphans)
+		cnt = c->cmt_orphans;
+	len = UBIFS_ORPH_NODE_SZ + cnt * sizeof(__le64);
+	ubifs_assert(c->orph_buf);
+	orph = c->orph_buf;
+	orph->ch.node_type = UBIFS_ORPH_NODE;
+	spin_lock(&c->orphan_lock);
+	cnext = c->orph_cnext;
+	for (i = 0; i < cnt; i++) {
+		orphan = cnext;
+		orph->inos[i] = cpu_to_le64(orphan->inum);
+		cnext = orphan->cnext;
+		orphan->cnext = NULL;
+	}
+	c->orph_cnext = cnext;
+	c->cmt_orphans -= cnt;
+	spin_unlock(&c->orphan_lock);
+	if (c->cmt_orphans)
+		orph->cmt_no = cpu_to_le64(c->cmt_no + 1);
+	else
+		/* Mark the last node of the commit */
+		orph->cmt_no = cpu_to_le64((c->cmt_no + 1) | (1ULL << 63));
+	ubifs_assert(c->ohead_offs + len <= c->leb_size);
+	ubifs_assert(c->ohead_lnum >= c->orph_first);
+	ubifs_assert(c->ohead_lnum <= c->orph_last);
+	err = do_write_orph_node(c, len, atomic);
+	c->ohead_offs += ALIGN(len, c->min_io_size);
+	c->ohead_offs = ALIGN(c->ohead_offs, 8);
+	return err;
+}
+
+/**
+ * write_orph_nodes - write orph nodes until there are no more to commit
+ * @c: UBIFS file-system description object
+ * @atomic: write atomically
+ *
+ * This function writes orph nodes for all the orphans to commit. On success,
+ * %0 is returned, otherwise a negative error code is returned.
+ */
+static int write_orph_nodes(struct ubifs_info *c, int atomic)
+{
+	int err;
+
+	while (c->cmt_orphans > 0) {
+		err = write_orph_node(c, atomic);
+		if (err)
+			return err;
+	}
+	if (atomic) {
+		int lnum;
+
+		/* Unmap any unused LEBs after consolidation */
+		lnum = c->ohead_lnum + 1;
+		for (lnum = c->ohead_lnum + 1; lnum <= c->orph_last; lnum++) {
+			err = ubifs_leb_unmap(c, lnum);
+			if (err)
+				return err;
+		}
+	}
+	return 0;
+}
+
+/**
+ * consolidate - consolidate the orphan area.
+ * @c: UBIFS file-system description object
+ *
+ * This function enables consolidation by putting all the orphans into the list
+ * to commit. The list is in the order that the orphans were added, and the
+ * LEBs are written atomically in order, so at no time can orphans be lost by
+ * an unclean unmount.
+ *
+ * This function returns %0 on success and a negative error code on failure.
+ */
+static int consolidate(struct ubifs_info *c)
+{
+	int tot_avail = tot_avail_orphs(c), err = 0;
+
+	spin_lock(&c->orphan_lock);
+	dbg_cmt("there is space for %d orphans and there are %d",
+		tot_avail, c->tot_orphans);
+	if (c->tot_orphans - c->new_orphans <= tot_avail) {
+		struct ubifs_orphan *orphan, **last;
+		int cnt = 0;
+
+		/* Change the cnext list to include all non-new orphans */
+		last = &c->orph_cnext;
+		list_for_each_entry(orphan, &c->orph_list, list) {
+			if (orphan->new)
+				continue;
+			*last = orphan;
+			last = &orphan->cnext;
+			cnt += 1;
+		}
+		*last = orphan->cnext;
+		ubifs_assert(cnt == c->tot_orphans - c->new_orphans);
+		c->cmt_orphans = cnt;
+		c->ohead_lnum = c->orph_first;
+		c->ohead_offs = 0;
+	} else {
+		/*
+		 * We limit the number of orphans so that this should
+		 * never happen.
+		 */
+		ubifs_err("out of space in orphan area");
+		err = -EINVAL;
+	}
+	spin_unlock(&c->orphan_lock);
+	return err;
+}
+
+/**
+ * commit_orphans - commit orphans.
+ * @c: UBIFS file-system description object
+ *
+ * This function commits orphans to flash. On success, %0 is returned,
+ * otherwise a negative error code is returned.
+ */
+static int commit_orphans(struct ubifs_info *c)
+{
+	int avail, atomic = 0, err;
+
+	ubifs_assert(c->cmt_orphans > 0);
+	avail = avail_orphs(c);
+	if (avail < c->cmt_orphans) {
+		/* Not enough space to write new orphans, so consolidate */
+		err = consolidate(c);
+		if (err)
+			return err;
+		atomic = 1;
+	}
+	err = write_orph_nodes(c, atomic);
+	return err;
+}
+
+/**
+ * erase_deleted - erase the orphans marked for deletion.
+ * @c: UBIFS file-system description object
+ *
+ * During commit, the orphans being committed cannot be deleted, so they are
+ * marked for deletion and deleted by this function. Also, the recovery
+ * adds killed orphans to the deletion list, and therefore they are deleted
+ * here too.
+ */
+static void erase_deleted(struct ubifs_info *c)
+{
+	struct ubifs_orphan *orphan, *dnext;
+
+	spin_lock(&c->orphan_lock);
+	dnext = c->orph_dnext;
+	while (dnext) {
+		orphan = dnext;
+		dnext = orphan->dnext;
+		ubifs_assert(!orphan->new);
+		rb_erase(&orphan->rb, &c->orph_tree);
+		list_del(&orphan->list);
+		c->tot_orphans -= 1;
+		dbg_gen("deleting orphan ino %lu", orphan->inum);
+		kfree(orphan);
+	}
+	c->orph_dnext = NULL;
+	spin_unlock(&c->orphan_lock);
+}
+
+/**
+ * ubifs_orphan_end_commit - end commit of orphans.
+ * @c: UBIFS file-system description object
+ *
+ * End commit of orphans.
+ */
+int ubifs_orphan_end_commit(struct ubifs_info *c)
+{
+	int err;
+
+	if (c->cmt_orphans != 0) {
+		err = commit_orphans(c);
+		if (err)
+			return err;
+	}
+	erase_deleted(c);
+	err = dbg_check_orphans(c);
+	return err;
+}
+
+/**
+ * clear_orphans - erase all LEBs used for orphans.
+ * @c: UBIFS file-system description object
+ *
+ * If recovery is not required, then the orphans from the previous session
+ * are not needed. This function locates the LEBs used to record
+ * orphans, and un-maps them.
+ */
+static int clear_orphans(struct ubifs_info *c)
+{
+	int lnum, err;
+
+	for (lnum = c->orph_first; lnum <= c->orph_last; lnum++) {
+		err = ubifs_leb_unmap(c, lnum);
+		if (err)
+			return err;
+	}
+	c->ohead_lnum = c->orph_first;
+	c->ohead_offs = 0;
+	return 0;
+}
+
+/**
+ * insert_dead_orphan - insert an orphan.
+ * @c: UBIFS file-system description object
+ * @inum: orphan inode number
+ *
+ * This function is a helper to the 'do_kill_orphans()' function. The orphan
+ * must be kept until the next commit, so it is added to the rb-tree and the
+ * deletion list.
+ */
+static int insert_dead_orphan(struct ubifs_info *c, ino_t inum)
+{
+	struct ubifs_orphan *orphan, *o;
+	struct rb_node **p, *parent = NULL;
+
+	orphan = kzalloc(sizeof(struct ubifs_orphan), GFP_KERNEL);
+	if (!orphan)
+		return -ENOMEM;
+	orphan->inum = inum;
+
+	p = &c->orph_tree.rb_node;
+	while (*p) {
+		parent = *p;
+		o = rb_entry(parent, struct ubifs_orphan, rb);
+		if (inum < o->inum)
+			p = &(*p)->rb_left;
+		else if (inum > o->inum)
+			p = &(*p)->rb_right;
+		else {
+			/* Already added - no problem */
+			kfree(orphan);
+			return 0;
+		}
+	}
+	c->tot_orphans += 1;
+	rb_link_node(&orphan->rb, parent, p);
+	rb_insert_color(&orphan->rb, &c->orph_tree);
+	list_add_tail(&orphan->list, &c->orph_list);
+	orphan->dnext = c->orph_dnext;
+	c->orph_dnext = orphan;
+	dbg_mnt("ino %lu, new %d, tot %d",
+		inum, c->new_orphans, c->tot_orphans);
+	return 0;
+}
+
+/**
+ * do_kill_orphans - remove orphan inodes from the index.
+ * @c: UBIFS file-system description object
+ * @sleb: scanned LEB
+ * @last_cmt_no: cmt_no of last orph node read is passed and returned here
+ * @outofdate: whether the LEB is out of date is returned here
+ * @last_flagged: whether the end orph node is encountered
+ *
+ * This function is a helper to the 'kill_orphans()' function. It goes through
+ * every orphan node in a LEB and for every inode number recorded, removes
+ * all keys for that inode from the TNC.
+ */
+static int do_kill_orphans(struct ubifs_info *c, struct ubifs_scan_leb *sleb,
+			   unsigned long long *last_cmt_no, int *outofdate,
+			   int *last_flagged)
+{
+	struct ubifs_scan_node *snod;
+	struct ubifs_orph_node *orph;
+	unsigned long long cmt_no;
+	ino_t inum;
+	int i, n, err, first = 1;
+
+	list_for_each_entry(snod, &sleb->nodes, list) {
+		if (snod->type != UBIFS_ORPH_NODE) {
+			ubifs_err("invalid node type %d in orphan area at "
+				  "%d:%d", snod->type, sleb->lnum, snod->offs);
+			dbg_dump_node(c, snod->node);
+			return -EINVAL;
+		}
+
+		orph = snod->node;
+
+		/* Check commit number */
+		cmt_no = le64_to_cpu(orph->cmt_no) & LLONG_MAX;
+		/*
+		 * The commit number on the master node may be less, because
+		 * of a failed commit. If there are several failed commits in a
+		 * row, the commit number written on orph nodes will continue to
+		 * increase (because the commit number is adjusted here) even
+		 * though the commit number on the master node stays the same
+		 * because the master node has not been re-written.
+		 */
+		if (cmt_no > c->cmt_no)
+			c->cmt_no = cmt_no;
+		if (cmt_no < *last_cmt_no && *last_flagged) {
+			/*
+			 * The last orph node had a higher commit number and was
+			 * flagged as the last written for that commit number.
+			 * That makes this orph node, out of date.
+			 */
+			if (!first) {
+				ubifs_err("out of order commit number %llu in "
+					  "orphan node at %d:%d",
+					  cmt_no, sleb->lnum, snod->offs);
+				dbg_dump_node(c, snod->node);
+				return -EINVAL;
+			}
+			dbg_rcvry("out of date LEB %d", sleb->lnum);
+			*outofdate = 1;
+			return 0;
+		}
+
+		if (first)
+			first = 0;
+
+		n = (le32_to_cpu(orph->ch.len) - UBIFS_ORPH_NODE_SZ) >> 3;
+		for (i = 0; i < n; i++) {
+			inum = le64_to_cpu(orph->inos[i]);
+			dbg_rcvry("deleting orphaned inode %lu", inum);
+			err = ubifs_tnc_remove_ino(c, inum);
+			if (err)
+				return err;
+			err = insert_dead_orphan(c, inum);
+			if (err)
+				return err;
+		}
+
+		*last_cmt_no = cmt_no;
+		if (le64_to_cpu(orph->cmt_no) & (1ULL << 63)) {
+			dbg_rcvry("last orph node for commit %llu at %d:%d",
+				  cmt_no, sleb->lnum, snod->offs);
+			*last_flagged = 1;
+		} else
+			*last_flagged = 0;
+	}
+
+	return 0;
+}
+
+/**
+ * kill_orphans - remove all orphan inodes from the index.
+ * @c: UBIFS file-system description object
+ *
+ * If recovery is required, then orphan inodes recorded during the previous
+ * session (which ended with an unclean unmount) must be deleted from the index.
+ * This is done by updating the TNC, but since the index is not updated until
+ * the next commit, the LEBs where the orphan information is recorded are not
+ * erased until the next commit.
+ */
+static int kill_orphans(struct ubifs_info *c)
+{
+	unsigned long long last_cmt_no = 0;
+	int lnum, err = 0, outofdate = 0, last_flagged = 0;
+
+	c->ohead_lnum = c->orph_first;
+	c->ohead_offs = 0;
+	/* Check no-orphans flag and skip this if no orphans */
+	if (c->no_orphs) {
+		dbg_rcvry("no orphans");
+		return 0;
+	}
+	/*
+	 * Orph nodes always start at c->orph_first and are written to each
+	 * successive LEB in turn. Generally unused LEBs will have been unmapped
+	 * but may contain out of date orph nodes if the unmap didn't go
+	 * through. In addition, the last orph node written for each commit is
+	 * marked (top bit of orph->cmt_no is set to 1). It is possible that
+	 * there are orph nodes from the next commit (i.e. the commit did not
+	 * complete successfully). In that case, no orphans will have been lost
+	 * due to the way that orphans are written, and any orphans added will
+	 * be valid orphans anyway and so can be deleted.
+	 */
+	for (lnum = c->orph_first; lnum <= c->orph_last; lnum++) {
+		struct ubifs_scan_leb *sleb;
+
+		dbg_rcvry("LEB %d", lnum);
+		sleb = ubifs_scan(c, lnum, 0, c->sbuf);
+		if (IS_ERR(sleb)) {
+			sleb = ubifs_recover_leb(c, lnum, 0, c->sbuf, 0);
+			if (IS_ERR(sleb)) {
+				err = PTR_ERR(sleb);
+				break;
+			}
+		}
+		err = do_kill_orphans(c, sleb, &last_cmt_no, &outofdate,
+				      &last_flagged);
+		if (err || outofdate) {
+			ubifs_scan_destroy(sleb);
+			break;
+		}
+		if (sleb->endpt) {
+			c->ohead_lnum = lnum;
+			c->ohead_offs = sleb->endpt;
+		}
+		ubifs_scan_destroy(sleb);
+	}
+	return err;
+}
+
+/**
+ * ubifs_mount_orphans - delete orphan inodes and erase LEBs that recorded them.
+ * @c: UBIFS file-system description object
+ * @unclean: indicates recovery from unclean unmount
+ * @read_only: indicates read only mount
+ *
+ * This function is called when mounting to erase orphans from the previous
+ * session. If UBIFS was not unmounted cleanly, then the inodes recorded as
+ * orphans are deleted.
+ */
+int ubifs_mount_orphans(struct ubifs_info *c, int unclean, int read_only)
+{
+	int err = 0;
+
+	c->max_orphans = tot_avail_orphs(c);
+
+	if (!read_only) {
+		c->orph_buf = vmalloc(c->leb_size);
+		if (!c->orph_buf)
+			return -ENOMEM;
+	}
+
+	if (unclean)
+		err = kill_orphans(c);
+	else if (!read_only)
+		err = clear_orphans(c);
+
+	return err;
+}
+
+#ifdef CONFIG_UBIFS_FS_DEBUG
+
+struct check_orphan {
+	struct rb_node rb;
+	ino_t inum;
+};
+
+struct check_info {
+	unsigned long last_ino;
+	unsigned long tot_inos;
+	unsigned long missing;
+	unsigned long long leaf_cnt;
+	struct ubifs_ino_node *node;
+	struct rb_root root;
+};
+
+static int dbg_find_orphan(struct ubifs_info *c, ino_t inum)
+{
+	struct ubifs_orphan *o;
+	struct rb_node *p;
+
+	spin_lock(&c->orphan_lock);
+	p = c->orph_tree.rb_node;
+	while (p) {
+		o = rb_entry(p, struct ubifs_orphan, rb);
+		if (inum < o->inum)
+			p = p->rb_left;
+		else if (inum > o->inum)
+			p = p->rb_right;
+		else {
+			spin_unlock(&c->orphan_lock);
+			return 1;
+		}
+	}
+	spin_unlock(&c->orphan_lock);
+	return 0;
+}
+
+static int dbg_ins_check_orphan(struct rb_root *root, ino_t inum)
+{
+	struct check_orphan *orphan, *o;
+	struct rb_node **p, *parent = NULL;
+
+	orphan = kzalloc(sizeof(struct check_orphan), GFP_NOFS);
+	if (!orphan)
+		return -ENOMEM;
+	orphan->inum = inum;
+
+	p = &root->rb_node;
+	while (*p) {
+		parent = *p;
+		o = rb_entry(parent, struct check_orphan, rb);
+		if (inum < o->inum)
+			p = &(*p)->rb_left;
+		else if (inum > o->inum)
+			p = &(*p)->rb_right;
+		else {
+			kfree(orphan);
+			return 0;
+		}
+	}
+	rb_link_node(&orphan->rb, parent, p);
+	rb_insert_color(&orphan->rb, root);
+	return 0;
+}
+
+static int dbg_find_check_orphan(struct rb_root *root, ino_t inum)
+{
+	struct check_orphan *o;
+	struct rb_node *p;
+
+	p = root->rb_node;
+	while (p) {
+		o = rb_entry(p, struct check_orphan, rb);
+		if (inum < o->inum)
+			p = p->rb_left;
+		else if (inum > o->inum)
+			p = p->rb_right;
+		else
+			return 1;
+	}
+	return 0;
+}
+
+static void dbg_free_check_tree(struct rb_root *root)
+{
+	struct rb_node *this = root->rb_node;
+	struct check_orphan *o;
+
+	while (this) {
+		if (this->rb_left) {
+			this = this->rb_left;
+			continue;
+		} else if (this->rb_right) {
+			this = this->rb_right;
+			continue;
+		}
+		o = rb_entry(this, struct check_orphan, rb);
+		this = rb_parent(this);
+		if (this) {
+			if (this->rb_left == &o->rb)
+				this->rb_left = NULL;
+			else
+				this->rb_right = NULL;
+		}
+		kfree(o);
+	}
+}
+
+static int dbg_orphan_check(struct ubifs_info *c, struct ubifs_zbranch *zbr,
+			    void *priv)
+{
+	struct check_info *ci = priv;
+	ino_t inum;
+	int err;
+
+	inum = key_inum(c, &zbr->key);
+	if (inum != ci->last_ino) {
+		/* Lowest node type is the inode node, so it comes first */
+		if (key_type(c, &zbr->key) != UBIFS_INO_KEY)
+			ubifs_err("found orphan node ino %lu, type %d", inum,
+				  key_type(c, &zbr->key));
+		ci->last_ino = inum;
+		ci->tot_inos += 1;
+		err = ubifs_tnc_read_node(c, zbr, ci->node);
+		if (err) {
+			ubifs_err("node read failed, error %d", err);
+			return err;
+		}
+		if (ci->node->nlink == 0)
+			/* Must be recorded as an orphan */
+			if (!dbg_find_check_orphan(&ci->root, inum) &&
+			    !dbg_find_orphan(c, inum)) {
+				ubifs_err("missing orphan, ino %lu", inum);
+				ci->missing += 1;
+			}
+	}
+	ci->leaf_cnt += 1;
+	return 0;
+}
+
+static int dbg_read_orphans(struct check_info *ci, struct ubifs_scan_leb *sleb)
+{
+	struct ubifs_scan_node *snod;
+	struct ubifs_orph_node *orph;
+	ino_t inum;
+	int i, n, err;
+
+	list_for_each_entry(snod, &sleb->nodes, list) {
+		cond_resched();
+		if (snod->type != UBIFS_ORPH_NODE)
+			continue;
+		orph = snod->node;
+		n = (le32_to_cpu(orph->ch.len) - UBIFS_ORPH_NODE_SZ) >> 3;
+		for (i = 0; i < n; i++) {
+			inum = le64_to_cpu(orph->inos[i]);
+			err = dbg_ins_check_orphan(&ci->root, inum);
+			if (err)
+				return err;
+		}
+	}
+	return 0;
+}
+
+static int dbg_scan_orphans(struct ubifs_info *c, struct check_info *ci)
+{
+	int lnum, err = 0;
+
+	/* Check no-orphans flag and skip this if no orphans */
+	if (c->no_orphs)
+		return 0;
+
+	for (lnum = c->orph_first; lnum <= c->orph_last; lnum++) {
+		struct ubifs_scan_leb *sleb;
+
+		sleb = ubifs_scan(c, lnum, 0, c->dbg_buf);
+		if (IS_ERR(sleb)) {
+			err = PTR_ERR(sleb);
+			break;
+		}
+
+		err = dbg_read_orphans(ci, sleb);
+		ubifs_scan_destroy(sleb);
+		if (err)
+			break;
+	}
+
+	return err;
+}
+
+static int dbg_check_orphans(struct ubifs_info *c)
+{
+	struct check_info ci;
+	int err;
+
+	if (!(ubifs_chk_flags & UBIFS_CHK_ORPH))
+		return 0;
+
+	ci.last_ino = 0;
+	ci.tot_inos = 0;
+	ci.missing  = 0;
+	ci.leaf_cnt = 0;
+	ci.root = RB_ROOT;
+	ci.node = kmalloc(UBIFS_MAX_INO_NODE_SZ, GFP_NOFS);
+	if (!ci.node) {
+		ubifs_err("out of memory");
+		return -ENOMEM;
+	}
+
+	err = dbg_scan_orphans(c, &ci);
+	if (err)
+		goto out;
+
+	err = dbg_walk_index(c, &dbg_orphan_check, NULL, &ci);
+	if (err) {
+		ubifs_err("cannot scan TNC, error %d", err);
+		goto out;
+	}
+
+	if (ci.missing) {
+		ubifs_err("%lu missing orphan(s)", ci.missing);
+		err = -EINVAL;
+		goto out;
+	}
+
+	dbg_cmt("last inode number is %lu", ci.last_ino);
+	dbg_cmt("total number of inodes is %lu", ci.tot_inos);
+	dbg_cmt("total number of leaf nodes is %llu", ci.leaf_cnt);
+
+out:
+	dbg_free_check_tree(&ci.root);
+	kfree(ci.node);
+	return err;
+}
+
+#endif /* CONFIG_UBIFS_FS_DEBUG */
diff --git a/fs/ubifs/recovery.c b/fs/ubifs/recovery.c
new file mode 100644
index 00000000000..77d26c141cf
--- /dev/null
+++ b/fs/ubifs/recovery.c
@@ -0,0 +1,1519 @@
+/*
+ * This file is part of UBIFS.
+ *
+ * Copyright (C) 2006-2008 Nokia Corporation
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 as published by
+ * the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
+ * more details.
+ *
+ * You should have received a copy of the GNU General Public License along with
+ * this program; if not, write to the Free Software Foundation, Inc., 51
+ * Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
+ *
+ * Authors: Adrian Hunter
+ *          Artem Bityutskiy (Битюцкий Артём)
+ */
+
+/*
+ * This file implements functions needed to recover from unclean un-mounts.
+ * When UBIFS is mounted, it checks a flag on the master node to determine if
+ * an un-mount was completed sucessfully. If not, the process of mounting
+ * incorparates additional checking and fixing of on-flash data structures.
+ * UBIFS always cleans away all remnants of an unclean un-mount, so that
+ * errors do not accumulate. However UBIFS defers recovery if it is mounted
+ * read-only, and the flash is not modified in that case.
+ */
+
+#include <linux/crc32.h>
+#include "ubifs.h"
+
+/**
+ * is_empty - determine whether a buffer is empty (contains all 0xff).
+ * @buf: buffer to clean
+ * @len: length of buffer
+ *
+ * This function returns %1 if the buffer is empty (contains all 0xff) otherwise
+ * %0 is returned.
+ */
+static int is_empty(void *buf, int len)
+{
+	uint8_t *p = buf;
+	int i;
+
+	for (i = 0; i < len; i++)
+		if (*p++ != 0xff)
+			return 0;
+	return 1;
+}
+
+/**
+ * get_master_node - get the last valid master node allowing for corruption.
+ * @c: UBIFS file-system description object
+ * @lnum: LEB number
+ * @pbuf: buffer containing the LEB read, is returned here
+ * @mst: master node, if found, is returned here
+ * @cor: corruption, if found, is returned here
+ *
+ * This function allocates a buffer, reads the LEB into it, and finds and
+ * returns the last valid master node allowing for one area of corruption.
+ * The corrupt area, if there is one, must be consistent with the assumption
+ * that it is the result of an unclean unmount while the master node was being
+ * written. Under those circumstances, it is valid to use the previously written
+ * master node.
+ *
+ * This function returns %0 on success and a negative error code on failure.
+ */
+static int get_master_node(const struct ubifs_info *c, int lnum, void **pbuf,
+			   struct ubifs_mst_node **mst, void **cor)
+{
+	const int sz = c->mst_node_alsz;
+	int err, offs, len;
+	void *sbuf, *buf;
+
+	sbuf = vmalloc(c->leb_size);
+	if (!sbuf)
+		return -ENOMEM;
+
+	err = ubi_read(c->ubi, lnum, sbuf, 0, c->leb_size);
+	if (err && err != -EBADMSG)
+		goto out_free;
+
+	/* Find the first position that is definitely not a node */
+	offs = 0;
+	buf = sbuf;
+	len = c->leb_size;
+	while (offs + UBIFS_MST_NODE_SZ <= c->leb_size) {
+		struct ubifs_ch *ch = buf;
+
+		if (le32_to_cpu(ch->magic) != UBIFS_NODE_MAGIC)
+			break;
+		offs += sz;
+		buf  += sz;
+		len  -= sz;
+	}
+	/* See if there was a valid master node before that */
+	if (offs) {
+		int ret;
+
+		offs -= sz;
+		buf  -= sz;
+		len  += sz;
+		ret = ubifs_scan_a_node(c, buf, len, lnum, offs, 1);
+		if (ret != SCANNED_A_NODE && offs) {
+			/* Could have been corruption so check one place back */
+			offs -= sz;
+			buf  -= sz;
+			len  += sz;
+			ret = ubifs_scan_a_node(c, buf, len, lnum, offs, 1);
+			if (ret != SCANNED_A_NODE)
+				/*
+				 * We accept only one area of corruption because
+				 * we are assuming that it was caused while
+				 * trying to write a master node.
+				 */
+				goto out_err;
+		}
+		if (ret == SCANNED_A_NODE) {
+			struct ubifs_ch *ch = buf;
+
+			if (ch->node_type != UBIFS_MST_NODE)
+				goto out_err;
+			dbg_rcvry("found a master node at %d:%d", lnum, offs);
+			*mst = buf;
+			offs += sz;
+			buf  += sz;
+			len  -= sz;
+		}
+	}
+	/* Check for corruption */
+	if (offs < c->leb_size) {
+		if (!is_empty(buf, min_t(int, len, sz))) {
+			*cor = buf;
+			dbg_rcvry("found corruption at %d:%d", lnum, offs);
+		}
+		offs += sz;
+		buf  += sz;
+		len  -= sz;
+	}
+	/* Check remaining empty space */
+	if (offs < c->leb_size)
+		if (!is_empty(buf, len))
+			goto out_err;
+	*pbuf = sbuf;
+	return 0;
+
+out_err:
+	err = -EINVAL;
+out_free:
+	vfree(sbuf);
+	*mst = NULL;
+	*cor = NULL;
+	return err;
+}
+
+/**
+ * write_rcvrd_mst_node - write recovered master node.
+ * @c: UBIFS file-system description object
+ * @mst: master node
+ *
+ * This function returns %0 on success and a negative error code on failure.
+ */
+static int write_rcvrd_mst_node(struct ubifs_info *c,
+				struct ubifs_mst_node *mst)
+{
+	int err = 0, lnum = UBIFS_MST_LNUM, sz = c->mst_node_alsz;
+	uint32_t save_flags;
+
+	dbg_rcvry("recovery");
+
+	save_flags = mst->flags;
+	mst->flags = cpu_to_le32(le32_to_cpu(mst->flags) | UBIFS_MST_RCVRY);
+
+	ubifs_prepare_node(c, mst, UBIFS_MST_NODE_SZ, 1);
+	err = ubi_leb_change(c->ubi, lnum, mst, sz, UBI_SHORTTERM);
+	if (err)
+		goto out;
+	err = ubi_leb_change(c->ubi, lnum + 1, mst, sz, UBI_SHORTTERM);
+	if (err)
+		goto out;
+out:
+	mst->flags = save_flags;
+	return err;
+}
+
+/**
+ * ubifs_recover_master_node - recover the master node.
+ * @c: UBIFS file-system description object
+ *
+ * This function recovers the master node from corruption that may occur due to
+ * an unclean unmount.
+ *
+ * This function returns %0 on success and a negative error code on failure.
+ */
+int ubifs_recover_master_node(struct ubifs_info *c)
+{
+	void *buf1 = NULL, *buf2 = NULL, *cor1 = NULL, *cor2 = NULL;
+	struct ubifs_mst_node *mst1 = NULL, *mst2 = NULL, *mst;
+	const int sz = c->mst_node_alsz;
+	int err, offs1, offs2;
+
+	dbg_rcvry("recovery");
+
+	err = get_master_node(c, UBIFS_MST_LNUM, &buf1, &mst1, &cor1);
+	if (err)
+		goto out_free;
+
+	err = get_master_node(c, UBIFS_MST_LNUM + 1, &buf2, &mst2, &cor2);
+	if (err)
+		goto out_free;
+
+	if (mst1) {
+		offs1 = (void *)mst1 - buf1;
+		if ((le32_to_cpu(mst1->flags) & UBIFS_MST_RCVRY) &&
+		    (offs1 == 0 && !cor1)) {
+			/*
+			 * mst1 was written by recovery at offset 0 with no
+			 * corruption.
+			 */
+			dbg_rcvry("recovery recovery");
+			mst = mst1;
+		} else if (mst2) {
+			offs2 = (void *)mst2 - buf2;
+			if (offs1 == offs2) {
+				/* Same offset, so must be the same */
+				if (memcmp((void *)mst1 + UBIFS_CH_SZ,
+					   (void *)mst2 + UBIFS_CH_SZ,
+					   UBIFS_MST_NODE_SZ - UBIFS_CH_SZ))
+					goto out_err;
+				mst = mst1;
+			} else if (offs2 + sz == offs1) {
+				/* 1st LEB was written, 2nd was not */
+				if (cor1)
+					goto out_err;
+				mst = mst1;
+			} else if (offs1 == 0 && offs2 + sz >= c->leb_size) {
+				/* 1st LEB was unmapped and written, 2nd not */
+				if (cor1)
+					goto out_err;
+				mst = mst1;
+			} else
+				goto out_err;
+		} else {
+			/*
+			 * 2nd LEB was unmapped and about to be written, so
+			 * there must be only one master node in the first LEB
+			 * and no corruption.
+			 */
+			if (offs1 != 0 || cor1)
+				goto out_err;
+			mst = mst1;
+		}
+	} else {
+		if (!mst2)
+			goto out_err;
+		/*
+		 * 1st LEB was unmapped and about to be written, so there must
+		 * be no room left in 2nd LEB.
+		 */
+		offs2 = (void *)mst2 - buf2;
+		if (offs2 + sz + sz <= c->leb_size)
+			goto out_err;
+		mst = mst2;
+	}
+
+	dbg_rcvry("recovered master node from LEB %d",
+		  (mst == mst1 ? UBIFS_MST_LNUM : UBIFS_MST_LNUM + 1));
+
+	memcpy(c->mst_node, mst, UBIFS_MST_NODE_SZ);
+
+	if ((c->vfs_sb->s_flags & MS_RDONLY)) {
+		/* Read-only mode. Keep a copy for switching to rw mode */
+		c->rcvrd_mst_node = kmalloc(sz, GFP_KERNEL);
+		if (!c->rcvrd_mst_node) {
+			err = -ENOMEM;
+			goto out_free;
+		}
+		memcpy(c->rcvrd_mst_node, c->mst_node, UBIFS_MST_NODE_SZ);
+	} else {
+		/* Write the recovered master node */
+		c->max_sqnum = le64_to_cpu(mst->ch.sqnum) - 1;
+		err = write_rcvrd_mst_node(c, c->mst_node);
+		if (err)
+			goto out_free;
+	}
+
+	vfree(buf2);
+	vfree(buf1);
+
+	return 0;
+
+out_err:
+	err = -EINVAL;
+out_free:
+	ubifs_err("failed to recover master node");
+	if (mst1) {
+		dbg_err("dumping first master node");
+		dbg_dump_node(c, mst1);
+	}
+	if (mst2) {
+		dbg_err("dumping second master node");
+		dbg_dump_node(c, mst2);
+	}
+	vfree(buf2);
+	vfree(buf1);
+	return err;
+}
+
+/**
+ * ubifs_write_rcvrd_mst_node - write the recovered master node.
+ * @c: UBIFS file-system description object
+ *
+ * This function writes the master node that was recovered during mounting in
+ * read-only mode and must now be written because we are remounting rw.
+ *
+ * This function returns %0 on success and a negative error code on failure.
+ */
+int ubifs_write_rcvrd_mst_node(struct ubifs_info *c)
+{
+	int err;
+
+	if (!c->rcvrd_mst_node)
+		return 0;
+	c->rcvrd_mst_node->flags |= cpu_to_le32(UBIFS_MST_DIRTY);
+	c->mst_node->flags |= cpu_to_le32(UBIFS_MST_DIRTY);
+	err = write_rcvrd_mst_node(c, c->rcvrd_mst_node);
+	if (err)
+		return err;
+	kfree(c->rcvrd_mst_node);
+	c->rcvrd_mst_node = NULL;
+	return 0;
+}
+
+/**
+ * is_last_write - determine if an offset was in the last write to a LEB.
+ * @c: UBIFS file-system description object
+ * @buf: buffer to check
+ * @offs: offset to check
+ *
+ * This function returns %1 if @offs was in the last write to the LEB whose data
+ * is in @buf, otherwise %0 is returned.  The determination is made by checking
+ * for subsequent empty space starting from the next min_io_size boundary (or a
+ * bit less than the common header size if min_io_size is one).
+ */
+static int is_last_write(const struct ubifs_info *c, void *buf, int offs)
+{
+	int empty_offs;
+	int check_len;
+	uint8_t *p;
+
+	if (c->min_io_size == 1) {
+		check_len = c->leb_size - offs;
+		p = buf + check_len;
+		for (; check_len > 0; check_len--)
+			if (*--p != 0xff)
+				break;
+		/*
+		 * 'check_len' is the size of the corruption which cannot be
+		 * more than the size of 1 node if it was caused by an unclean
+		 * unmount.
+		 */
+		if (check_len > UBIFS_MAX_NODE_SZ)
+			return 0;
+		return 1;
+	}
+
+	/*
+	 * Round up to the next c->min_io_size boundary i.e. 'offs' is in the
+	 * last wbuf written. After that should be empty space.
+	 */
+	empty_offs = ALIGN(offs + 1, c->min_io_size);
+	check_len = c->leb_size - empty_offs;
+	p = buf + empty_offs - offs;
+
+	for (; check_len > 0; check_len--)
+		if (*p++ != 0xff)
+			return 0;
+	return 1;
+}
+
+/**
+ * clean_buf - clean the data from an LEB sitting in a buffer.
+ * @c: UBIFS file-system description object
+ * @buf: buffer to clean
+ * @lnum: LEB number to clean
+ * @offs: offset from which to clean
+ * @len: length of buffer
+ *
+ * This function pads up to the next min_io_size boundary (if there is one) and
+ * sets empty space to all 0xff. @buf, @offs and @len are updated to the next
+ * min_io_size boundary (if there is one).
+ */
+static void clean_buf(const struct ubifs_info *c, void **buf, int lnum,
+		      int *offs, int *len)
+{
+	int empty_offs, pad_len;
+
+	lnum = lnum;
+	dbg_rcvry("cleaning corruption at %d:%d", lnum, *offs);
+
+	if (c->min_io_size == 1) {
+		memset(*buf, 0xff, c->leb_size - *offs);
+		return;
+	}
+
+	ubifs_assert(!(*offs & 7));
+	empty_offs = ALIGN(*offs, c->min_io_size);
+	pad_len = empty_offs - *offs;
+	ubifs_pad(c, *buf, pad_len);
+	*offs += pad_len;
+	*buf += pad_len;
+	*len -= pad_len;
+	memset(*buf, 0xff, c->leb_size - empty_offs);
+}
+
+/**
+ * no_more_nodes - determine if there are no more nodes in a buffer.
+ * @c: UBIFS file-system description object
+ * @buf: buffer to check
+ * @len: length of buffer
+ * @lnum: LEB number of the LEB from which @buf was read
+ * @offs: offset from which @buf was read
+ *
+ * This function scans @buf for more nodes and returns %0 is a node is found and
+ * %1 if no more nodes are found.
+ */
+static int no_more_nodes(const struct ubifs_info *c, void *buf, int len,
+			int lnum, int offs)
+{
+	int skip, next_offs = 0;
+
+	if (len > UBIFS_DATA_NODE_SZ) {
+		struct ubifs_ch *ch = buf;
+		int dlen = le32_to_cpu(ch->len);
+
+		if (ch->node_type == UBIFS_DATA_NODE && dlen >= UBIFS_CH_SZ &&
+		    dlen <= UBIFS_MAX_DATA_NODE_SZ)
+			/* The corrupt node looks like a data node */
+			next_offs = ALIGN(offs + dlen, 8);
+	}
+
+	if (c->min_io_size == 1)
+		skip = 8;
+	else
+		skip = ALIGN(offs + 1, c->min_io_size) - offs;
+
+	offs += skip;
+	buf += skip;
+	len -= skip;
+	while (len > 8) {
+		struct ubifs_ch *ch = buf;
+		uint32_t magic = le32_to_cpu(ch->magic);
+		int ret;
+
+		if (magic == UBIFS_NODE_MAGIC) {
+			ret = ubifs_scan_a_node(c, buf, len, lnum, offs, 1);
+			if (ret == SCANNED_A_NODE || ret > 0) {
+				/*
+				 * There is a small chance this is just data in
+				 * a data node, so check that possibility. e.g.
+				 * this is part of a file that itself contains
+				 * a UBIFS image.
+				 */
+				if (next_offs && offs + le32_to_cpu(ch->len) <=
+				    next_offs)
+					continue;
+				dbg_rcvry("unexpected node at %d:%d", lnum,
+					  offs);
+				return 0;
+			}
+		}
+		offs += 8;
+		buf += 8;
+		len -= 8;
+	}
+	return 1;
+}
+
+/**
+ * fix_unclean_leb - fix an unclean LEB.
+ * @c: UBIFS file-system description object
+ * @sleb: scanned LEB information
+ * @start: offset where scan started
+ */
+static int fix_unclean_leb(struct ubifs_info *c, struct ubifs_scan_leb *sleb,
+			   int start)
+{
+	int lnum = sleb->lnum, endpt = start;
+
+	/* Get the end offset of the last node we are keeping */
+	if (!list_empty(&sleb->nodes)) {
+		struct ubifs_scan_node *snod;
+
+		snod = list_entry(sleb->nodes.prev,
+				  struct ubifs_scan_node, list);
+		endpt = snod->offs + snod->len;
+	}
+
+	if ((c->vfs_sb->s_flags & MS_RDONLY) && !c->remounting_rw) {
+		/* Add to recovery list */
+		struct ubifs_unclean_leb *ucleb;
+
+		dbg_rcvry("need to fix LEB %d start %d endpt %d",
+			  lnum, start, sleb->endpt);
+		ucleb = kzalloc(sizeof(struct ubifs_unclean_leb), GFP_NOFS);
+		if (!ucleb)
+			return -ENOMEM;
+		ucleb->lnum = lnum;
+		ucleb->endpt = endpt;
+		list_add_tail(&ucleb->list, &c->unclean_leb_list);
+	} else {
+		/* Write the fixed LEB back to flash */
+		int err;
+
+		dbg_rcvry("fixing LEB %d start %d endpt %d",
+			  lnum, start, sleb->endpt);
+		if (endpt == 0) {
+			err = ubifs_leb_unmap(c, lnum);
+			if (err)
+				return err;
+		} else {
+			int len = ALIGN(endpt, c->min_io_size);
+
+			if (start) {
+				err = ubi_read(c->ubi, lnum, sleb->buf, 0,
+					       start);
+				if (err)
+					return err;
+			}
+			/* Pad to min_io_size */
+			if (len > endpt) {
+				int pad_len = len - ALIGN(endpt, 8);
+
+				if (pad_len > 0) {
+					void *buf = sleb->buf + len - pad_len;
+
+					ubifs_pad(c, buf, pad_len);
+				}
+			}
+			err = ubi_leb_change(c->ubi, lnum, sleb->buf, len,
+					     UBI_UNKNOWN);
+			if (err)
+				return err;
+		}
+	}
+	return 0;
+}
+
+/**
+ * drop_incomplete_group - drop nodes from an incomplete group.
+ * @sleb: scanned LEB information
+ * @offs: offset of dropped nodes is returned here
+ *
+ * This function returns %1 if nodes are dropped and %0 otherwise.
+ */
+static int drop_incomplete_group(struct ubifs_scan_leb *sleb, int *offs)
+{
+	int dropped = 0;
+
+	while (!list_empty(&sleb->nodes)) {
+		struct ubifs_scan_node *snod;
+		struct ubifs_ch *ch;
+
+		snod = list_entry(sleb->nodes.prev, struct ubifs_scan_node,
+				  list);
+		ch = snod->node;
+		if (ch->group_type != UBIFS_IN_NODE_GROUP)
+			return dropped;
+		dbg_rcvry("dropping node at %d:%d", sleb->lnum, snod->offs);
+		*offs = snod->offs;
+		list_del(&snod->list);
+		kfree(snod);
+		sleb->nodes_cnt -= 1;
+		dropped = 1;
+	}
+	return dropped;
+}
+
+/**
+ * ubifs_recover_leb - scan and recover a LEB.
+ * @c: UBIFS file-system description object
+ * @lnum: LEB number
+ * @offs: offset
+ * @sbuf: LEB-sized buffer to use
+ * @grouped: nodes may be grouped for recovery
+ *
+ * This function does a scan of a LEB, but caters for errors that might have
+ * been caused by the unclean unmount from which we are attempting to recover.
+ *
+ * This function returns %0 on success and a negative error code on failure.
+ */
+struct ubifs_scan_leb *ubifs_recover_leb(struct ubifs_info *c, int lnum,
+					 int offs, void *sbuf, int grouped)
+{
+	int err, len = c->leb_size - offs, need_clean = 0, quiet = 1;
+	int empty_chkd = 0, start = offs;
+	struct ubifs_scan_leb *sleb;
+	void *buf = sbuf + offs;
+
+	dbg_rcvry("%d:%d", lnum, offs);
+
+	sleb = ubifs_start_scan(c, lnum, offs, sbuf);
+	if (IS_ERR(sleb))
+		return sleb;
+
+	if (sleb->ecc)
+		need_clean = 1;
+
+	while (len >= 8) {
+		int ret;
+
+		dbg_scan("look at LEB %d:%d (%d bytes left)",
+			 lnum, offs, len);
+
+		cond_resched();
+
+		/*
+		 * Scan quietly until there is an error from which we cannot
+		 * recover
+		 */
+		ret = ubifs_scan_a_node(c, buf, len, lnum, offs, quiet);
+
+		if (ret == SCANNED_A_NODE) {
+			/* A valid node, and not a padding node */
+			struct ubifs_ch *ch = buf;
+			int node_len;
+
+			err = ubifs_add_snod(c, sleb, buf, offs);
+			if (err)
+				goto error;
+			node_len = ALIGN(le32_to_cpu(ch->len), 8);
+			offs += node_len;
+			buf += node_len;
+			len -= node_len;
+			continue;
+		}
+
+		if (ret > 0) {
+			/* Padding bytes or a valid padding node */
+			offs += ret;
+			buf += ret;
+			len -= ret;
+			continue;
+		}
+
+		if (ret == SCANNED_EMPTY_SPACE) {
+			if (!is_empty(buf, len)) {
+				if (!is_last_write(c, buf, offs))
+					break;
+				clean_buf(c, &buf, lnum, &offs, &len);
+				need_clean = 1;
+			}
+			empty_chkd = 1;
+			break;
+		}
+
+		if (ret == SCANNED_GARBAGE || ret == SCANNED_A_BAD_PAD_NODE)
+			if (is_last_write(c, buf, offs)) {
+				clean_buf(c, &buf, lnum, &offs, &len);
+				need_clean = 1;
+				empty_chkd = 1;
+				break;
+			}
+
+		if (ret == SCANNED_A_CORRUPT_NODE)
+			if (no_more_nodes(c, buf, len, lnum, offs)) {
+				clean_buf(c, &buf, lnum, &offs, &len);
+				need_clean = 1;
+				empty_chkd = 1;
+				break;
+			}
+
+		if (quiet) {
+			/* Redo the last scan but noisily */
+			quiet = 0;
+			continue;
+		}
+
+		switch (ret) {
+		case SCANNED_GARBAGE:
+			dbg_err("garbage");
+			goto corrupted;
+		case SCANNED_A_CORRUPT_NODE:
+		case SCANNED_A_BAD_PAD_NODE:
+			dbg_err("bad node");
+			goto corrupted;
+		default:
+			dbg_err("unknown");
+			goto corrupted;
+		}
+	}
+
+	if (!empty_chkd && !is_empty(buf, len)) {
+		if (is_last_write(c, buf, offs)) {
+			clean_buf(c, &buf, lnum, &offs, &len);
+			need_clean = 1;
+		} else {
+			ubifs_err("corrupt empty space at LEB %d:%d",
+				  lnum, offs);
+			goto corrupted;
+		}
+	}
+
+	/* Drop nodes from incomplete group */
+	if (grouped && drop_incomplete_group(sleb, &offs)) {
+		buf = sbuf + offs;
+		len = c->leb_size - offs;
+		clean_buf(c, &buf, lnum, &offs, &len);
+		need_clean = 1;
+	}
+
+	if (offs % c->min_io_size) {
+		clean_buf(c, &buf, lnum, &offs, &len);
+		need_clean = 1;
+	}
+
+	ubifs_end_scan(c, sleb, lnum, offs);
+
+	if (need_clean) {
+		err = fix_unclean_leb(c, sleb, start);
+		if (err)
+			goto error;
+	}
+
+	return sleb;
+
+corrupted:
+	ubifs_scanned_corruption(c, lnum, offs, buf);
+	err = -EUCLEAN;
+error:
+	ubifs_err("LEB %d scanning failed", lnum);
+	ubifs_scan_destroy(sleb);
+	return ERR_PTR(err);
+}
+
+/**
+ * get_cs_sqnum - get commit start sequence number.
+ * @c: UBIFS file-system description object
+ * @lnum: LEB number of commit start node
+ * @offs: offset of commit start node
+ * @cs_sqnum: commit start sequence number is returned here
+ *
+ * This function returns %0 on success and a negative error code on failure.
+ */
+static int get_cs_sqnum(struct ubifs_info *c, int lnum, int offs,
+			unsigned long long *cs_sqnum)
+{
+	struct ubifs_cs_node *cs_node = NULL;
+	int err, ret;
+
+	dbg_rcvry("at %d:%d", lnum, offs);
+	cs_node = kmalloc(UBIFS_CS_NODE_SZ, GFP_KERNEL);
+	if (!cs_node)
+		return -ENOMEM;
+	if (c->leb_size - offs < UBIFS_CS_NODE_SZ)
+		goto out_err;
+	err = ubi_read(c->ubi, lnum, (void *)cs_node, offs, UBIFS_CS_NODE_SZ);
+	if (err && err != -EBADMSG)
+		goto out_free;
+	ret = ubifs_scan_a_node(c, cs_node, UBIFS_CS_NODE_SZ, lnum, offs, 0);
+	if (ret != SCANNED_A_NODE) {
+		dbg_err("Not a valid node");
+		goto out_err;
+	}
+	if (cs_node->ch.node_type != UBIFS_CS_NODE) {
+		dbg_err("Node a CS node, type is %d", cs_node->ch.node_type);
+		goto out_err;
+	}
+	if (le64_to_cpu(cs_node->cmt_no) != c->cmt_no) {
+		dbg_err("CS node cmt_no %llu != current cmt_no %llu",
+			(unsigned long long)le64_to_cpu(cs_node->cmt_no),
+			c->cmt_no);
+		goto out_err;
+	}
+	*cs_sqnum = le64_to_cpu(cs_node->ch.sqnum);
+	dbg_rcvry("commit start sqnum %llu", *cs_sqnum);
+	kfree(cs_node);
+	return 0;
+
+out_err:
+	err = -EINVAL;
+out_free:
+	ubifs_err("failed to get CS sqnum");
+	kfree(cs_node);
+	return err;
+}
+
+/**
+ * ubifs_recover_log_leb - scan and recover a log LEB.
+ * @c: UBIFS file-system description object
+ * @lnum: LEB number
+ * @offs: offset
+ * @sbuf: LEB-sized buffer to use
+ *
+ * This function does a scan of a LEB, but caters for errors that might have
+ * been caused by the unclean unmount from which we are attempting to recover.
+ *
+ * This function returns %0 on success and a negative error code on failure.
+ */
+struct ubifs_scan_leb *ubifs_recover_log_leb(struct ubifs_info *c, int lnum,
+					     int offs, void *sbuf)
+{
+	struct ubifs_scan_leb *sleb;
+	int next_lnum;
+
+	dbg_rcvry("LEB %d", lnum);
+	next_lnum = lnum + 1;
+	if (next_lnum >= UBIFS_LOG_LNUM + c->log_lebs)
+		next_lnum = UBIFS_LOG_LNUM;
+	if (next_lnum != c->ltail_lnum) {
+		/*
+		 * We can only recover at the end of the log, so check that the
+		 * next log LEB is empty or out of date.
+		 */
+		sleb = ubifs_scan(c, next_lnum, 0, sbuf);
+		if (IS_ERR(sleb))
+			return sleb;
+		if (sleb->nodes_cnt) {
+			struct ubifs_scan_node *snod;
+			unsigned long long cs_sqnum = c->cs_sqnum;
+
+			snod = list_entry(sleb->nodes.next,
+					  struct ubifs_scan_node, list);
+			if (cs_sqnum == 0) {
+				int err;
+
+				err = get_cs_sqnum(c, lnum, offs, &cs_sqnum);
+				if (err) {
+					ubifs_scan_destroy(sleb);
+					return ERR_PTR(err);
+				}
+			}
+			if (snod->sqnum > cs_sqnum) {
+				ubifs_err("unrecoverable log corruption "
+					  "in LEB %d", lnum);
+				ubifs_scan_destroy(sleb);
+				return ERR_PTR(-EUCLEAN);
+			}
+		}
+		ubifs_scan_destroy(sleb);
+	}
+	return ubifs_recover_leb(c, lnum, offs, sbuf, 0);
+}
+
+/**
+ * recover_head - recover a head.
+ * @c: UBIFS file-system description object
+ * @lnum: LEB number of head to recover
+ * @offs: offset of head to recover
+ * @sbuf: LEB-sized buffer to use
+ *
+ * This function ensures that there is no data on the flash at a head location.
+ *
+ * This function returns %0 on success and a negative error code on failure.
+ */
+static int recover_head(const struct ubifs_info *c, int lnum, int offs,
+			void *sbuf)
+{
+	int len, err, need_clean = 0;
+
+	if (c->min_io_size > 1)
+		len = c->min_io_size;
+	else
+		len = 512;
+	if (offs + len > c->leb_size)
+		len = c->leb_size - offs;
+
+	if (!len)
+		return 0;
+
+	/* Read at the head location and check it is empty flash */
+	err = ubi_read(c->ubi, lnum, sbuf, offs, len);
+	if (err)
+		need_clean = 1;
+	else {
+		uint8_t *p = sbuf;
+
+		while (len--)
+			if (*p++ != 0xff) {
+				need_clean = 1;
+				break;
+			}
+	}
+
+	if (need_clean) {
+		dbg_rcvry("cleaning head at %d:%d", lnum, offs);
+		if (offs == 0)
+			return ubifs_leb_unmap(c, lnum);
+		err = ubi_read(c->ubi, lnum, sbuf, 0, offs);
+		if (err)
+			return err;
+		return ubi_leb_change(c->ubi, lnum, sbuf, offs, UBI_UNKNOWN);
+	}
+
+	return 0;
+}
+
+/**
+ * ubifs_recover_inl_heads - recover index and LPT heads.
+ * @c: UBIFS file-system description object
+ * @sbuf: LEB-sized buffer to use
+ *
+ * This function ensures that there is no data on the flash at the index and
+ * LPT head locations.
+ *
+ * This deals with the recovery of a half-completed journal commit. UBIFS is
+ * careful never to overwrite the last version of the index or the LPT. Because
+ * the index and LPT are wandering trees, data from a half-completed commit will
+ * not be referenced anywhere in UBIFS. The data will be either in LEBs that are
+ * assumed to be empty and will be unmapped anyway before use, or in the index
+ * and LPT heads.
+ *
+ * This function returns %0 on success and a negative error code on failure.
+ */
+int ubifs_recover_inl_heads(const struct ubifs_info *c, void *sbuf)
+{
+	int err;
+
+	ubifs_assert(!(c->vfs_sb->s_flags & MS_RDONLY) || c->remounting_rw);
+
+	dbg_rcvry("checking index head at %d:%d", c->ihead_lnum, c->ihead_offs);
+	err = recover_head(c, c->ihead_lnum, c->ihead_offs, sbuf);
+	if (err)
+		return err;
+
+	dbg_rcvry("checking LPT head at %d:%d", c->nhead_lnum, c->nhead_offs);
+	err = recover_head(c, c->nhead_lnum, c->nhead_offs, sbuf);
+	if (err)
+		return err;
+
+	return 0;
+}
+
+/**
+ *  clean_an_unclean_leb - read and write a LEB to remove corruption.
+ * @c: UBIFS file-system description object
+ * @ucleb: unclean LEB information
+ * @sbuf: LEB-sized buffer to use
+ *
+ * This function reads a LEB up to a point pre-determined by the mount recovery,
+ * checks the nodes, and writes the result back to the flash, thereby cleaning
+ * off any following corruption, or non-fatal ECC errors.
+ *
+ * This function returns %0 on success and a negative error code on failure.
+ */
+static int clean_an_unclean_leb(const struct ubifs_info *c,
+				struct ubifs_unclean_leb *ucleb, void *sbuf)
+{
+	int err, lnum = ucleb->lnum, offs = 0, len = ucleb->endpt, quiet = 1;
+	void *buf = sbuf;
+
+	dbg_rcvry("LEB %d len %d", lnum, len);
+
+	if (len == 0) {
+		/* Nothing to read, just unmap it */
+		err = ubifs_leb_unmap(c, lnum);
+		if (err)
+			return err;
+		return 0;
+	}
+
+	err = ubi_read(c->ubi, lnum, buf, offs, len);
+	if (err && err != -EBADMSG)
+		return err;
+
+	while (len >= 8) {
+		int ret;
+
+		cond_resched();
+
+		/* Scan quietly until there is an error */
+		ret = ubifs_scan_a_node(c, buf, len, lnum, offs, quiet);
+
+		if (ret == SCANNED_A_NODE) {
+			/* A valid node, and not a padding node */
+			struct ubifs_ch *ch = buf;
+			int node_len;
+
+			node_len = ALIGN(le32_to_cpu(ch->len), 8);
+			offs += node_len;
+			buf += node_len;
+			len -= node_len;
+			continue;
+		}
+
+		if (ret > 0) {
+			/* Padding bytes or a valid padding node */
+			offs += ret;
+			buf += ret;
+			len -= ret;
+			continue;
+		}
+
+		if (ret == SCANNED_EMPTY_SPACE) {
+			ubifs_err("unexpected empty space at %d:%d",
+				  lnum, offs);
+			return -EUCLEAN;
+		}
+
+		if (quiet) {
+			/* Redo the last scan but noisily */
+			quiet = 0;
+			continue;
+		}
+
+		ubifs_scanned_corruption(c, lnum, offs, buf);
+		return -EUCLEAN;
+	}
+
+	/* Pad to min_io_size */
+	len = ALIGN(ucleb->endpt, c->min_io_size);
+	if (len > ucleb->endpt) {
+		int pad_len = len - ALIGN(ucleb->endpt, 8);
+
+		if (pad_len > 0) {
+			buf = c->sbuf + len - pad_len;
+			ubifs_pad(c, buf, pad_len);
+		}
+	}
+
+	/* Write back the LEB atomically */
+	err = ubi_leb_change(c->ubi, lnum, sbuf, len, UBI_UNKNOWN);
+	if (err)
+		return err;
+
+	dbg_rcvry("cleaned LEB %d", lnum);
+
+	return 0;
+}
+
+/**
+ * ubifs_clean_lebs - clean LEBs recovered during read-only mount.
+ * @c: UBIFS file-system description object
+ * @sbuf: LEB-sized buffer to use
+ *
+ * This function cleans a LEB identified during recovery that needs to be
+ * written but was not because UBIFS was mounted read-only. This happens when
+ * remounting to read-write mode.
+ *
+ * This function returns %0 on success and a negative error code on failure.
+ */
+int ubifs_clean_lebs(const struct ubifs_info *c, void *sbuf)
+{
+	dbg_rcvry("recovery");
+	while (!list_empty(&c->unclean_leb_list)) {
+		struct ubifs_unclean_leb *ucleb;
+		int err;
+
+		ucleb = list_entry(c->unclean_leb_list.next,
+				   struct ubifs_unclean_leb, list);
+		err = clean_an_unclean_leb(c, ucleb, sbuf);
+		if (err)
+			return err;
+		list_del(&ucleb->list);
+		kfree(ucleb);
+	}
+	return 0;
+}
+
+/**
+ * ubifs_rcvry_gc_commit - recover the GC LEB number and run the commit.
+ * @c: UBIFS file-system description object
+ *
+ * Out-of-place garbage collection requires always one empty LEB with which to
+ * start garbage collection. The LEB number is recorded in c->gc_lnum and is
+ * written to the master node on unmounting. In the case of an unclean unmount
+ * the value of gc_lnum recorded in the master node is out of date and cannot
+ * be used. Instead, recovery must allocate an empty LEB for this purpose.
+ * However, there may not be enough empty space, in which case it must be
+ * possible to GC the dirtiest LEB into the GC head LEB.
+ *
+ * This function also runs the commit which causes the TNC updates from
+ * size-recovery and orphans to be written to the flash. That is important to
+ * ensure correct replay order for subsequent mounts.
+ *
+ * This function returns %0 on success and a negative error code on failure.
+ */
+int ubifs_rcvry_gc_commit(struct ubifs_info *c)
+{
+	struct ubifs_wbuf *wbuf = &c->jheads[GCHD].wbuf;
+	struct ubifs_lprops lp;
+	int lnum, err;
+
+	c->gc_lnum = -1;
+	if (wbuf->lnum == -1) {
+		dbg_rcvry("no GC head LEB");
+		goto find_free;
+	}
+	/*
+	 * See whether the used space in the dirtiest LEB fits in the GC head
+	 * LEB.
+	 */
+	if (wbuf->offs == c->leb_size) {
+		dbg_rcvry("no room in GC head LEB");
+		goto find_free;
+	}
+	err = ubifs_find_dirty_leb(c, &lp, wbuf->offs, 2);
+	if (err) {
+		if (err == -ENOSPC)
+			dbg_err("could not find a dirty LEB");
+		return err;
+	}
+	ubifs_assert(!(lp.flags & LPROPS_INDEX));
+	lnum = lp.lnum;
+	if (lp.free + lp.dirty == c->leb_size) {
+		/* An empty LEB was returned */
+		if (lp.free != c->leb_size) {
+			err = ubifs_change_one_lp(c, lnum, c->leb_size,
+						  0, 0, 0, 0);
+			if (err)
+				return err;
+		}
+		err = ubifs_leb_unmap(c, lnum);
+		if (err)
+			return err;
+		c->gc_lnum = lnum;
+		dbg_rcvry("allocated LEB %d for GC", lnum);
+		/* Run the commit */
+		dbg_rcvry("committing");
+		return ubifs_run_commit(c);
+	}
+	/*
+	 * There was no empty LEB so the used space in the dirtiest LEB must fit
+	 * in the GC head LEB.
+	 */
+	if (lp.free + lp.dirty < wbuf->offs) {
+		dbg_rcvry("LEB %d doesn't fit in GC head LEB %d:%d",
+			  lnum, wbuf->lnum, wbuf->offs);
+		err = ubifs_return_leb(c, lnum);
+		if (err)
+			return err;
+		goto find_free;
+	}
+	/*
+	 * We run the commit before garbage collection otherwise subsequent
+	 * mounts will see the GC and orphan deletion in a different order.
+	 */
+	dbg_rcvry("committing");
+	err = ubifs_run_commit(c);
+	if (err)
+		return err;
+	/*
+	 * The data in the dirtiest LEB fits in the GC head LEB, so do the GC
+	 * - use locking to keep 'ubifs_assert()' happy.
+	 */
+	dbg_rcvry("GC'ing LEB %d", lnum);
+	mutex_lock_nested(&wbuf->io_mutex, wbuf->jhead);
+	err = ubifs_garbage_collect_leb(c, &lp);
+	if (err >= 0) {
+		int err2 = ubifs_wbuf_sync_nolock(wbuf);
+
+		if (err2)
+			err = err2;
+	}
+	mutex_unlock(&wbuf->io_mutex);
+	if (err < 0) {
+		dbg_err("GC failed, error %d", err);
+		if (err == -EAGAIN)
+			err = -EINVAL;
+		return err;
+	}
+	if (err != LEB_RETAINED) {
+		dbg_err("GC returned %d", err);
+		return -EINVAL;
+	}
+	err = ubifs_leb_unmap(c, c->gc_lnum);
+	if (err)
+		return err;
+	dbg_rcvry("allocated LEB %d for GC", lnum);
+	return 0;
+
+find_free:
+	/*
+	 * There is no GC head LEB or the free space in the GC head LEB is too
+	 * small. Allocate gc_lnum by calling 'ubifs_find_free_leb_for_idx()' so
+	 * GC is not run.
+	 */
+	lnum = ubifs_find_free_leb_for_idx(c);
+	if (lnum < 0) {
+		dbg_err("could not find an empty LEB");
+		return lnum;
+	}
+	/* And reset the index flag */
+	err = ubifs_change_one_lp(c, lnum, LPROPS_NC, LPROPS_NC, 0,
+				  LPROPS_INDEX, 0);
+	if (err)
+		return err;
+	c->gc_lnum = lnum;
+	dbg_rcvry("allocated LEB %d for GC", lnum);
+	/* Run the commit */
+	dbg_rcvry("committing");
+	return ubifs_run_commit(c);
+}
+
+/**
+ * struct size_entry - inode size information for recovery.
+ * @rb: link in the RB-tree of sizes
+ * @inum: inode number
+ * @i_size: size on inode
+ * @d_size: maximum size based on data nodes
+ * @exists: indicates whether the inode exists
+ * @inode: inode if pinned in memory awaiting rw mode to fix it
+ */
+struct size_entry {
+	struct rb_node rb;
+	ino_t inum;
+	loff_t i_size;
+	loff_t d_size;
+	int exists;
+	struct inode *inode;
+};
+
+/**
+ * add_ino - add an entry to the size tree.
+ * @c: UBIFS file-system description object
+ * @inum: inode number
+ * @i_size: size on inode
+ * @d_size: maximum size based on data nodes
+ * @exists: indicates whether the inode exists
+ */
+static int add_ino(struct ubifs_info *c, ino_t inum, loff_t i_size,
+		   loff_t d_size, int exists)
+{
+	struct rb_node **p = &c->size_tree.rb_node, *parent = NULL;
+	struct size_entry *e;
+
+	while (*p) {
+		parent = *p;
+		e = rb_entry(parent, struct size_entry, rb);
+		if (inum < e->inum)
+			p = &(*p)->rb_left;
+		else
+			p = &(*p)->rb_right;
+	}
+
+	e = kzalloc(sizeof(struct size_entry), GFP_KERNEL);
+	if (!e)
+		return -ENOMEM;
+
+	e->inum = inum;
+	e->i_size = i_size;
+	e->d_size = d_size;
+	e->exists = exists;
+
+	rb_link_node(&e->rb, parent, p);
+	rb_insert_color(&e->rb, &c->size_tree);
+
+	return 0;
+}
+
+/**
+ * find_ino - find an entry on the size tree.
+ * @c: UBIFS file-system description object
+ * @inum: inode number
+ */
+static struct size_entry *find_ino(struct ubifs_info *c, ino_t inum)
+{
+	struct rb_node *p = c->size_tree.rb_node;
+	struct size_entry *e;
+
+	while (p) {
+		e = rb_entry(p, struct size_entry, rb);
+		if (inum < e->inum)
+			p = p->rb_left;
+		else if (inum > e->inum)
+			p = p->rb_right;
+		else
+			return e;
+	}
+	return NULL;
+}
+
+/**
+ * remove_ino - remove an entry from the size tree.
+ * @c: UBIFS file-system description object
+ * @inum: inode number
+ */
+static void remove_ino(struct ubifs_info *c, ino_t inum)
+{
+	struct size_entry *e = find_ino(c, inum);
+
+	if (!e)
+		return;
+	rb_erase(&e->rb, &c->size_tree);
+	kfree(e);
+}
+
+/**
+ * ubifs_destroy_size_tree - free resources related to the size tree.
+ * @c: UBIFS file-system description object
+ */
+void ubifs_destroy_size_tree(struct ubifs_info *c)
+{
+	struct rb_node *this = c->size_tree.rb_node;
+	struct size_entry *e;
+
+	while (this) {
+		if (this->rb_left) {
+			this = this->rb_left;
+			continue;
+		} else if (this->rb_right) {
+			this = this->rb_right;
+			continue;
+		}
+		e = rb_entry(this, struct size_entry, rb);
+		if (e->inode)
+			iput(e->inode);
+		this = rb_parent(this);
+		if (this) {
+			if (this->rb_left == &e->rb)
+				this->rb_left = NULL;
+			else
+				this->rb_right = NULL;
+		}
+		kfree(e);
+	}
+	c->size_tree = RB_ROOT;
+}
+
+/**
+ * ubifs_recover_size_accum - accumulate inode sizes for recovery.
+ * @c: UBIFS file-system description object
+ * @key: node key
+ * @deletion: node is for a deletion
+ * @new_size: inode size
+ *
+ * This function has two purposes:
+ *     1) to ensure there are no data nodes that fall outside the inode size
+ *     2) to ensure there are no data nodes for inodes that do not exist
+ * To accomplish those purposes, a rb-tree is constructed containing an entry
+ * for each inode number in the journal that has not been deleted, and recording
+ * the size from the inode node, the maximum size of any data node (also altered
+ * by truncations) and a flag indicating a inode number for which no inode node
+ * was present in the journal.
+ *
+ * Note that there is still the possibility that there are data nodes that have
+ * been committed that are beyond the inode size, however the only way to find
+ * them would be to scan the entire index. Alternatively, some provision could
+ * be made to record the size of inodes at the start of commit, which would seem
+ * very cumbersome for a scenario that is quite unlikely and the only negative
+ * consequence of which is wasted space.
+ *
+ * This functions returns %0 on success and a negative error code on failure.
+ */
+int ubifs_recover_size_accum(struct ubifs_info *c, union ubifs_key *key,
+			     int deletion, loff_t new_size)
+{
+	ino_t inum = key_inum(c, key);
+	struct size_entry *e;
+	int err;
+
+	switch (key_type(c, key)) {
+	case UBIFS_INO_KEY:
+		if (deletion)
+			remove_ino(c, inum);
+		else {
+			e = find_ino(c, inum);
+			if (e) {
+				e->i_size = new_size;
+				e->exists = 1;
+			} else {
+				err = add_ino(c, inum, new_size, 0, 1);
+				if (err)
+					return err;
+			}
+		}
+		break;
+	case UBIFS_DATA_KEY:
+		e = find_ino(c, inum);
+		if (e) {
+			if (new_size > e->d_size)
+				e->d_size = new_size;
+		} else {
+			err = add_ino(c, inum, 0, new_size, 0);
+			if (err)
+				return err;
+		}
+		break;
+	case UBIFS_TRUN_KEY:
+		e = find_ino(c, inum);
+		if (e)
+			e->d_size = new_size;
+		break;
+	}
+	return 0;
+}
+
+/**
+ * fix_size_in_place - fix inode size in place on flash.
+ * @c: UBIFS file-system description object
+ * @e: inode size information for recovery
+ */
+static int fix_size_in_place(struct ubifs_info *c, struct size_entry *e)
+{
+	struct ubifs_ino_node *ino = c->sbuf;
+	unsigned char *p;
+	union ubifs_key key;
+	int err, lnum, offs, len;
+	loff_t i_size;
+	uint32_t crc;
+
+	/* Locate the inode node LEB number and offset */
+	ino_key_init(c, &key, e->inum);
+	err = ubifs_tnc_locate(c, &key, ino, &lnum, &offs);
+	if (err)
+		goto out;
+	/*
+	 * If the size recorded on the inode node is greater than the size that
+	 * was calculated from nodes in the journal then don't change the inode.
+	 */
+	i_size = le64_to_cpu(ino->size);
+	if (i_size >= e->d_size)
+		return 0;
+	/* Read the LEB */
+	err = ubi_read(c->ubi, lnum, c->sbuf, 0, c->leb_size);
+	if (err)
+		goto out;
+	/* Change the size field and recalculate the CRC */
+	ino = c->sbuf + offs;
+	ino->size = cpu_to_le64(e->d_size);
+	len = le32_to_cpu(ino->ch.len);
+	crc = crc32(UBIFS_CRC32_INIT, (void *)ino + 8, len - 8);
+	ino->ch.crc = cpu_to_le32(crc);
+	/* Work out where data in the LEB ends and free space begins */
+	p = c->sbuf;
+	len = c->leb_size - 1;
+	while (p[len] == 0xff)
+		len -= 1;
+	len = ALIGN(len + 1, c->min_io_size);
+	/* Atomically write the fixed LEB back again */
+	err = ubi_leb_change(c->ubi, lnum, c->sbuf, len, UBI_UNKNOWN);
+	if (err)
+		goto out;
+	dbg_rcvry("inode %lu at %d:%d size %lld -> %lld ", e->inum, lnum, offs,
+		  i_size, e->d_size);
+	return 0;
+
+out:
+	ubifs_warn("inode %lu failed to fix size %lld -> %lld error %d",
+		   e->inum, e->i_size, e->d_size, err);
+	return err;
+}
+
+/**
+ * ubifs_recover_size - recover inode size.
+ * @c: UBIFS file-system description object
+ *
+ * This function attempts to fix inode size discrepancies identified by the
+ * 'ubifs_recover_size_accum()' function.
+ *
+ * This functions returns %0 on success and a negative error code on failure.
+ */
+int ubifs_recover_size(struct ubifs_info *c)
+{
+	struct rb_node *this = rb_first(&c->size_tree);
+
+	while (this) {
+		struct size_entry *e;
+		int err;
+
+		e = rb_entry(this, struct size_entry, rb);
+		if (!e->exists) {
+			union ubifs_key key;
+
+			ino_key_init(c, &key, e->inum);
+			err = ubifs_tnc_lookup(c, &key, c->sbuf);
+			if (err && err != -ENOENT)
+				return err;
+			if (err == -ENOENT) {
+				/* Remove data nodes that have no inode */
+				dbg_rcvry("removing ino %lu", e->inum);
+				err = ubifs_tnc_remove_ino(c, e->inum);
+				if (err)
+					return err;
+			} else {
+				struct ubifs_ino_node *ino = c->sbuf;
+
+				e->exists = 1;
+				e->i_size = le64_to_cpu(ino->size);
+			}
+		}
+		if (e->exists && e->i_size < e->d_size) {
+			if (!e->inode && (c->vfs_sb->s_flags & MS_RDONLY)) {
+				/* Fix the inode size and pin it in memory */
+				struct inode *inode;
+
+				inode = ubifs_iget(c->vfs_sb, e->inum);
+				if (IS_ERR(inode))
+					return PTR_ERR(inode);
+				if (inode->i_size < e->d_size) {
+					dbg_rcvry("ino %lu size %lld -> %lld",
+						  e->inum, e->d_size,
+						  inode->i_size);
+					inode->i_size = e->d_size;
+					ubifs_inode(inode)->ui_size = e->d_size;
+					e->inode = inode;
+					this = rb_next(this);
+					continue;
+				}
+				iput(inode);
+			} else {
+				/* Fix the size in place */
+				err = fix_size_in_place(c, e);
+				if (err)
+					return err;
+				if (e->inode)
+					iput(e->inode);
+			}
+		}
+		this = rb_next(this);
+		rb_erase(&e->rb, &c->size_tree);
+		kfree(e);
+	}
+	return 0;
+}
diff --git a/fs/ubifs/replay.c b/fs/ubifs/replay.c
new file mode 100644
index 00000000000..7399692af85
--- /dev/null
+++ b/fs/ubifs/replay.c
@@ -0,0 +1,1075 @@
+/*
+ * This file is part of UBIFS.
+ *
+ * Copyright (C) 2006-2008 Nokia Corporation.
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 as published by
+ * the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
+ * more details.
+ *
+ * You should have received a copy of the GNU General Public License along with
+ * this program; if not, write to the Free Software Foundation, Inc., 51
+ * Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
+ *
+ * Authors: Adrian Hunter
+ *          Artem Bityutskiy (Битюцкий Артём)
+ */
+
+/*
+ * This file contains journal replay code. It runs when the file-system is being
+ * mounted and requires no locking.
+ *
+ * The larger is the journal, the longer it takes to scan it, so the longer it
+ * takes to mount UBIFS. This is why the journal has limited size which may be
+ * changed depending on the system requirements. But a larger journal gives
+ * faster I/O speed because it writes the index less frequently. So this is a
+ * trade-off. Also, the journal is indexed by the in-memory index (TNC), so the
+ * larger is the journal, the more memory its index may consume.
+ */
+
+#include "ubifs.h"
+
+/*
+ * Replay flags.
+ *
+ * REPLAY_DELETION: node was deleted
+ * REPLAY_REF: node is a reference node
+ */
+enum {
+	REPLAY_DELETION = 1,
+	REPLAY_REF = 2,
+};
+
+/**
+ * struct replay_entry - replay tree entry.
+ * @lnum: logical eraseblock number of the node
+ * @offs: node offset
+ * @len: node length
+ * @sqnum: node sequence number
+ * @flags: replay flags
+ * @rb: links the replay tree
+ * @key: node key
+ * @nm: directory entry name
+ * @old_size: truncation old size
+ * @new_size: truncation new size
+ * @free: amount of free space in a bud
+ * @dirty: amount of dirty space in a bud from padding and deletion nodes
+ *
+ * UBIFS journal replay must compare node sequence numbers, which means it must
+ * build a tree of node information to insert into the TNC.
+ */
+struct replay_entry {
+	int lnum;
+	int offs;
+	int len;
+	unsigned long long sqnum;
+	int flags;
+	struct rb_node rb;
+	union ubifs_key key;
+	union {
+		struct qstr nm;
+		struct {
+			loff_t old_size;
+			loff_t new_size;
+		};
+		struct {
+			int free;
+			int dirty;
+		};
+	};
+};
+
+/**
+ * struct bud_entry - entry in the list of buds to replay.
+ * @list: next bud in the list
+ * @bud: bud description object
+ * @free: free bytes in the bud
+ * @sqnum: reference node sequence number
+ */
+struct bud_entry {
+	struct list_head list;
+	struct ubifs_bud *bud;
+	int free;
+	unsigned long long sqnum;
+};
+
+/**
+ * set_bud_lprops - set free and dirty space used by a bud.
+ * @c: UBIFS file-system description object
+ * @r: replay entry of bud
+ */
+static int set_bud_lprops(struct ubifs_info *c, struct replay_entry *r)
+{
+	const struct ubifs_lprops *lp;
+	int err = 0, dirty;
+
+	ubifs_get_lprops(c);
+
+	lp = ubifs_lpt_lookup_dirty(c, r->lnum);
+	if (IS_ERR(lp)) {
+		err = PTR_ERR(lp);
+		goto out;
+	}
+
+	dirty = lp->dirty;
+	if (r->offs == 0 && (lp->free != c->leb_size || lp->dirty != 0)) {
+		/*
+		 * The LEB was added to the journal with a starting offset of
+		 * zero which means the LEB must have been empty. The LEB
+		 * property values should be lp->free == c->leb_size and
+		 * lp->dirty == 0, but that is not the case. The reason is that
+		 * the LEB was garbage collected. The garbage collector resets
+		 * the free and dirty space without recording it anywhere except
+		 * lprops, so if there is not a commit then lprops does not have
+		 * that information next time the file system is mounted.
+		 *
+		 * We do not need to adjust free space because the scan has told
+		 * us the exact value which is recorded in the replay entry as
+		 * r->free.
+		 *
+		 * However we do need to subtract from the dirty space the
+		 * amount of space that the garbage collector reclaimed, which
+		 * is the whole LEB minus the amount of space that was free.
+		 */
+		dbg_mnt("bud LEB %d was GC'd (%d free, %d dirty)", r->lnum,
+			lp->free, lp->dirty);
+		dbg_gc("bud LEB %d was GC'd (%d free, %d dirty)", r->lnum,
+			lp->free, lp->dirty);
+		dirty -= c->leb_size - lp->free;
+		/*
+		 * If the replay order was perfect the dirty space would now be
+		 * zero. The order is not perfect because the the journal heads
+		 * race with eachother. This is not a problem but is does mean
+		 * that the dirty space may temporarily exceed c->leb_size
+		 * during the replay.
+		 */
+		if (dirty != 0)
+			dbg_msg("LEB %d lp: %d free %d dirty "
+				"replay: %d free %d dirty", r->lnum, lp->free,
+				lp->dirty, r->free, r->dirty);
+	}
+	lp = ubifs_change_lp(c, lp, r->free, dirty + r->dirty,
+			     lp->flags | LPROPS_TAKEN, 0);
+	if (IS_ERR(lp)) {
+		err = PTR_ERR(lp);
+		goto out;
+	}
+out:
+	ubifs_release_lprops(c);
+	return err;
+}
+
+/**
+ * trun_remove_range - apply a replay entry for a truncation to the TNC.
+ * @c: UBIFS file-system description object
+ * @r: replay entry of truncation
+ */
+static int trun_remove_range(struct ubifs_info *c, struct replay_entry *r)
+{
+	unsigned min_blk, max_blk;
+	union ubifs_key min_key, max_key;
+	ino_t ino;
+
+	min_blk = r->new_size / UBIFS_BLOCK_SIZE;
+	if (r->new_size & (UBIFS_BLOCK_SIZE - 1))
+		min_blk += 1;
+
+	max_blk = r->old_size / UBIFS_BLOCK_SIZE;
+	if ((r->old_size & (UBIFS_BLOCK_SIZE - 1)) == 0)
+		max_blk -= 1;
+
+	ino = key_inum(c, &r->key);
+
+	data_key_init(c, &min_key, ino, min_blk);
+	data_key_init(c, &max_key, ino, max_blk);
+
+	return ubifs_tnc_remove_range(c, &min_key, &max_key);
+}
+
+/**
+ * apply_replay_entry - apply a replay entry to the TNC.
+ * @c: UBIFS file-system description object
+ * @r: replay entry to apply
+ *
+ * Apply a replay entry to the TNC.
+ */
+static int apply_replay_entry(struct ubifs_info *c, struct replay_entry *r)
+{
+	int err, deletion = ((r->flags & REPLAY_DELETION) != 0);
+
+	dbg_mnt("LEB %d:%d len %d flgs %d sqnum %llu %s", r->lnum,
+		r->offs, r->len, r->flags, r->sqnum, DBGKEY(&r->key));
+
+	/* Set c->replay_sqnum to help deal with dangling branches. */
+	c->replay_sqnum = r->sqnum;
+
+	if (r->flags & REPLAY_REF)
+		err = set_bud_lprops(c, r);
+	else if (is_hash_key(c, &r->key)) {
+		if (deletion)
+			err = ubifs_tnc_remove_nm(c, &r->key, &r->nm);
+		else
+			err = ubifs_tnc_add_nm(c, &r->key, r->lnum, r->offs,
+					       r->len, &r->nm);
+	} else {
+		if (deletion)
+			switch (key_type(c, &r->key)) {
+			case UBIFS_INO_KEY:
+			{
+				ino_t inum = key_inum(c, &r->key);
+
+				err = ubifs_tnc_remove_ino(c, inum);
+				break;
+			}
+			case UBIFS_TRUN_KEY:
+				err = trun_remove_range(c, r);
+				break;
+			default:
+				err = ubifs_tnc_remove(c, &r->key);
+				break;
+			}
+		else
+			err = ubifs_tnc_add(c, &r->key, r->lnum, r->offs,
+					    r->len);
+		if (err)
+			return err;
+
+		if (c->need_recovery)
+			err = ubifs_recover_size_accum(c, &r->key, deletion,
+						       r->new_size);
+	}
+
+	return err;
+}
+
+/**
+ * destroy_replay_tree - destroy the replay.
+ * @c: UBIFS file-system description object
+ *
+ * Destroy the replay tree.
+ */
+static void destroy_replay_tree(struct ubifs_info *c)
+{
+	struct rb_node *this = c->replay_tree.rb_node;
+	struct replay_entry *r;
+
+	while (this) {
+		if (this->rb_left) {
+			this = this->rb_left;
+			continue;
+		} else if (this->rb_right) {
+			this = this->rb_right;
+			continue;
+		}
+		r = rb_entry(this, struct replay_entry, rb);
+		this = rb_parent(this);
+		if (this) {
+			if (this->rb_left == &r->rb)
+				this->rb_left = NULL;
+			else
+				this->rb_right = NULL;
+		}
+		if (is_hash_key(c, &r->key))
+			kfree(r->nm.name);
+		kfree(r);
+	}
+	c->replay_tree = RB_ROOT;
+}
+
+/**
+ * apply_replay_tree - apply the replay tree to the TNC.
+ * @c: UBIFS file-system description object
+ *
+ * Apply the replay tree.
+ * Returns zero in case of success and a negative error code in case of
+ * failure.
+ */
+static int apply_replay_tree(struct ubifs_info *c)
+{
+	struct rb_node *this = rb_first(&c->replay_tree);
+
+	while (this) {
+		struct replay_entry *r;
+		int err;
+
+		cond_resched();
+
+		r = rb_entry(this, struct replay_entry, rb);
+		err = apply_replay_entry(c, r);
+		if (err)
+			return err;
+		this = rb_next(this);
+	}
+	return 0;
+}
+
+/**
+ * insert_node - insert a node to the replay tree.
+ * @c: UBIFS file-system description object
+ * @lnum: node logical eraseblock number
+ * @offs: node offset
+ * @len: node length
+ * @key: node key
+ * @sqnum: sequence number
+ * @deletion: non-zero if this is a deletion
+ * @used: number of bytes in use in a LEB
+ * @old_size: truncation old size
+ * @new_size: truncation new size
+ *
+ * This function inserts a scanned non-direntry node to the replay tree. The
+ * replay tree is an RB-tree containing @struct replay_entry elements which are
+ * indexed by the sequence number. The replay tree is applied at the very end
+ * of the replay process. Since the tree is sorted in sequence number order,
+ * the older modifications are applied first. This function returns zero in
+ * case of success and a negative error code in case of failure.
+ */
+static int insert_node(struct ubifs_info *c, int lnum, int offs, int len,
+		       union ubifs_key *key, unsigned long long sqnum,
+		       int deletion, int *used, loff_t old_size,
+		       loff_t new_size)
+{
+	struct rb_node **p = &c->replay_tree.rb_node, *parent = NULL;
+	struct replay_entry *r;
+
+	if (key_inum(c, key) >= c->highest_inum)
+		c->highest_inum = key_inum(c, key);
+
+	dbg_mnt("add LEB %d:%d, key %s", lnum, offs, DBGKEY(key));
+	while (*p) {
+		parent = *p;
+		r = rb_entry(parent, struct replay_entry, rb);
+		if (sqnum < r->sqnum) {
+			p = &(*p)->rb_left;
+			continue;
+		} else if (sqnum > r->sqnum) {
+			p = &(*p)->rb_right;
+			continue;
+		}
+		ubifs_err("duplicate sqnum in replay");
+		return -EINVAL;
+	}
+
+	r = kzalloc(sizeof(struct replay_entry), GFP_KERNEL);
+	if (!r)
+		return -ENOMEM;
+
+	if (!deletion)
+		*used += ALIGN(len, 8);
+	r->lnum = lnum;
+	r->offs = offs;
+	r->len = len;
+	r->sqnum = sqnum;
+	r->flags = (deletion ? REPLAY_DELETION : 0);
+	r->old_size = old_size;
+	r->new_size = new_size;
+	key_copy(c, key, &r->key);
+
+	rb_link_node(&r->rb, parent, p);
+	rb_insert_color(&r->rb, &c->replay_tree);
+	return 0;
+}
+
+/**
+ * insert_dent - insert a directory entry node into the replay tree.
+ * @c: UBIFS file-system description object
+ * @lnum: node logical eraseblock number
+ * @offs: node offset
+ * @len: node length
+ * @key: node key
+ * @name: directory entry name
+ * @nlen: directory entry name length
+ * @sqnum: sequence number
+ * @deletion: non-zero if this is a deletion
+ * @used: number of bytes in use in a LEB
+ *
+ * This function inserts a scanned directory entry node to the replay tree.
+ * Returns zero in case of success and a negative error code in case of
+ * failure.
+ *
+ * This function is also used for extended attribute entries because they are
+ * implemented as directory entry nodes.
+ */
+static int insert_dent(struct ubifs_info *c, int lnum, int offs, int len,
+		       union ubifs_key *key, const char *name, int nlen,
+		       unsigned long long sqnum, int deletion, int *used)
+{
+	struct rb_node **p = &c->replay_tree.rb_node, *parent = NULL;
+	struct replay_entry *r;
+	char *nbuf;
+
+	if (key_inum(c, key) >= c->highest_inum)
+		c->highest_inum = key_inum(c, key);
+
+	dbg_mnt("add LEB %d:%d, key %s", lnum, offs, DBGKEY(key));
+	while (*p) {
+		parent = *p;
+		r = rb_entry(parent, struct replay_entry, rb);
+		if (sqnum < r->sqnum) {
+			p = &(*p)->rb_left;
+			continue;
+		}
+		if (sqnum > r->sqnum) {
+			p = &(*p)->rb_right;
+			continue;
+		}
+		ubifs_err("duplicate sqnum in replay");
+		return -EINVAL;
+	}
+
+	r = kzalloc(sizeof(struct replay_entry), GFP_KERNEL);
+	if (!r)
+		return -ENOMEM;
+	nbuf = kmalloc(nlen + 1, GFP_KERNEL);
+	if (!nbuf) {
+		kfree(r);
+		return -ENOMEM;
+	}
+
+	if (!deletion)
+		*used += ALIGN(len, 8);
+	r->lnum = lnum;
+	r->offs = offs;
+	r->len = len;
+	r->sqnum = sqnum;
+	r->nm.len = nlen;
+	memcpy(nbuf, name, nlen);
+	nbuf[nlen] = '\0';
+	r->nm.name = nbuf;
+	r->flags = (deletion ? REPLAY_DELETION : 0);
+	key_copy(c, key, &r->key);
+
+	ubifs_assert(!*p);
+	rb_link_node(&r->rb, parent, p);
+	rb_insert_color(&r->rb, &c->replay_tree);
+	return 0;
+}
+
+/**
+ * ubifs_validate_entry - validate directory or extended attribute entry node.
+ * @c: UBIFS file-system description object
+ * @dent: the node to validate
+ *
+ * This function validates directory or extended attribute entry node @dent.
+ * Returns zero if the node is all right and a %-EINVAL if not.
+ */
+int ubifs_validate_entry(struct ubifs_info *c,
+			 const struct ubifs_dent_node *dent)
+{
+	int key_type = key_type_flash(c, dent->key);
+	int nlen = le16_to_cpu(dent->nlen);
+
+	if (le32_to_cpu(dent->ch.len) != nlen + UBIFS_DENT_NODE_SZ + 1 ||
+	    dent->type >= UBIFS_ITYPES_CNT ||
+	    nlen > UBIFS_MAX_NLEN || dent->name[nlen] != 0 ||
+	    strnlen(dent->name, nlen) != nlen ||
+	    le64_to_cpu(dent->inum) > MAX_INUM) {
+		ubifs_err("bad %s node", key_type == UBIFS_DENT_KEY ?
+			  "directory entry" : "extended attribute entry");
+		return -EINVAL;
+	}
+
+	if (key_type != UBIFS_DENT_KEY && key_type != UBIFS_XENT_KEY) {
+		ubifs_err("bad key type %d", key_type);
+		return -EINVAL;
+	}
+
+	return 0;
+}
+
+/**
+ * replay_bud - replay a bud logical eraseblock.
+ * @c: UBIFS file-system description object
+ * @lnum: bud logical eraseblock number to replay
+ * @offs: bud start offset
+ * @jhead: journal head to which this bud belongs
+ * @free: amount of free space in the bud is returned here
+ * @dirty: amount of dirty space from padding and deletion nodes is returned
+ * here
+ *
+ * This function returns zero in case of success and a negative error code in
+ * case of failure.
+ */
+static int replay_bud(struct ubifs_info *c, int lnum, int offs, int jhead,
+		      int *free, int *dirty)
+{
+	int err = 0, used = 0;
+	struct ubifs_scan_leb *sleb;
+	struct ubifs_scan_node *snod;
+	struct ubifs_bud *bud;
+
+	dbg_mnt("replay bud LEB %d, head %d", lnum, jhead);
+	if (c->need_recovery)
+		sleb = ubifs_recover_leb(c, lnum, offs, c->sbuf, jhead != GCHD);
+	else
+		sleb = ubifs_scan(c, lnum, offs, c->sbuf);
+	if (IS_ERR(sleb))
+		return PTR_ERR(sleb);
+
+	/*
+	 * The bud does not have to start from offset zero - the beginning of
+	 * the 'lnum' LEB may contain previously committed data. One of the
+	 * things we have to do in replay is to correctly update lprops with
+	 * newer information about this LEB.
+	 *
+	 * At this point lprops thinks that this LEB has 'c->leb_size - offs'
+	 * bytes of free space because it only contain information about
+	 * committed data.
+	 *
+	 * But we know that real amount of free space is 'c->leb_size -
+	 * sleb->endpt', and the space in the 'lnum' LEB between 'offs' and
+	 * 'sleb->endpt' is used by bud data. We have to correctly calculate
+	 * how much of these data are dirty and update lprops with this
+	 * information.
+	 *
+	 * The dirt in that LEB region is comprised of padding nodes, deletion
+	 * nodes, truncation nodes and nodes which are obsoleted by subsequent
+	 * nodes in this LEB. So instead of calculating clean space, we
+	 * calculate used space ('used' variable).
+	 */
+
+	list_for_each_entry(snod, &sleb->nodes, list) {
+		int deletion = 0;
+
+		cond_resched();
+
+		if (snod->sqnum >= SQNUM_WATERMARK) {
+			ubifs_err("file system's life ended");
+			goto out_dump;
+		}
+
+		if (snod->sqnum > c->max_sqnum)
+			c->max_sqnum = snod->sqnum;
+
+		switch (snod->type) {
+		case UBIFS_INO_NODE:
+		{
+			struct ubifs_ino_node *ino = snod->node;
+			loff_t new_size = le64_to_cpu(ino->size);
+
+			if (le32_to_cpu(ino->nlink) == 0)
+				deletion = 1;
+			err = insert_node(c, lnum, snod->offs, snod->len,
+					  &snod->key, snod->sqnum, deletion,
+					  &used, 0, new_size);
+			break;
+		}
+		case UBIFS_DATA_NODE:
+		{
+			struct ubifs_data_node *dn = snod->node;
+			loff_t new_size = le32_to_cpu(dn->size) +
+					  key_block(c, &snod->key) *
+					  UBIFS_BLOCK_SIZE;
+
+			err = insert_node(c, lnum, snod->offs, snod->len,
+					  &snod->key, snod->sqnum, deletion,
+					  &used, 0, new_size);
+			break;
+		}
+		case UBIFS_DENT_NODE:
+		case UBIFS_XENT_NODE:
+		{
+			struct ubifs_dent_node *dent = snod->node;
+
+			err = ubifs_validate_entry(c, dent);
+			if (err)
+				goto out_dump;
+
+			err = insert_dent(c, lnum, snod->offs, snod->len,
+					  &snod->key, dent->name,
+					  le16_to_cpu(dent->nlen), snod->sqnum,
+					  !le64_to_cpu(dent->inum), &used);
+			break;
+		}
+		case UBIFS_TRUN_NODE:
+		{
+			struct ubifs_trun_node *trun = snod->node;
+			loff_t old_size = le64_to_cpu(trun->old_size);
+			loff_t new_size = le64_to_cpu(trun->new_size);
+			union ubifs_key key;
+
+			/* Validate truncation node */
+			if (old_size < 0 || old_size > c->max_inode_sz ||
+			    new_size < 0 || new_size > c->max_inode_sz ||
+			    old_size <= new_size) {
+				ubifs_err("bad truncation node");
+				goto out_dump;
+			}
+
+			/*
+			 * Create a fake truncation key just to use the same
+			 * functions which expect nodes to have keys.
+			 */
+			trun_key_init(c, &key, le32_to_cpu(trun->inum));
+			err = insert_node(c, lnum, snod->offs, snod->len,
+					  &key, snod->sqnum, 1, &used,
+					  old_size, new_size);
+			break;
+		}
+		default:
+			ubifs_err("unexpected node type %d in bud LEB %d:%d",
+				  snod->type, lnum, snod->offs);
+			err = -EINVAL;
+			goto out_dump;
+		}
+		if (err)
+			goto out;
+	}
+
+	bud = ubifs_search_bud(c, lnum);
+	if (!bud)
+		BUG();
+
+	ubifs_assert(sleb->endpt - offs >= used);
+	ubifs_assert(sleb->endpt % c->min_io_size == 0);
+
+	if (sleb->endpt + c->min_io_size <= c->leb_size &&
+	    !(c->vfs_sb->s_flags & MS_RDONLY))
+		err = ubifs_wbuf_seek_nolock(&c->jheads[jhead].wbuf, lnum,
+					     sleb->endpt, UBI_SHORTTERM);
+
+	*dirty = sleb->endpt - offs - used;
+	*free = c->leb_size - sleb->endpt;
+
+out:
+	ubifs_scan_destroy(sleb);
+	return err;
+
+out_dump:
+	ubifs_err("bad node is at LEB %d:%d", lnum, snod->offs);
+	dbg_dump_node(c, snod->node);
+	ubifs_scan_destroy(sleb);
+	return -EINVAL;
+}
+
+/**
+ * insert_ref_node - insert a reference node to the replay tree.
+ * @c: UBIFS file-system description object
+ * @lnum: node logical eraseblock number
+ * @offs: node offset
+ * @sqnum: sequence number
+ * @free: amount of free space in bud
+ * @dirty: amount of dirty space from padding and deletion nodes
+ *
+ * This function inserts a reference node to the replay tree and returns zero
+ * in case of success ort a negative error code in case of failure.
+ */
+static int insert_ref_node(struct ubifs_info *c, int lnum, int offs,
+			   unsigned long long sqnum, int free, int dirty)
+{
+	struct rb_node **p = &c->replay_tree.rb_node, *parent = NULL;
+	struct replay_entry *r;
+
+	dbg_mnt("add ref LEB %d:%d", lnum, offs);
+	while (*p) {
+		parent = *p;
+		r = rb_entry(parent, struct replay_entry, rb);
+		if (sqnum < r->sqnum) {
+			p = &(*p)->rb_left;
+			continue;
+		} else if (sqnum > r->sqnum) {
+			p = &(*p)->rb_right;
+			continue;
+		}
+		ubifs_err("duplicate sqnum in replay tree");
+		return -EINVAL;
+	}
+
+	r = kzalloc(sizeof(struct replay_entry), GFP_KERNEL);
+	if (!r)
+		return -ENOMEM;
+
+	r->lnum = lnum;
+	r->offs = offs;
+	r->sqnum = sqnum;
+	r->flags = REPLAY_REF;
+	r->free = free;
+	r->dirty = dirty;
+
+	rb_link_node(&r->rb, parent, p);
+	rb_insert_color(&r->rb, &c->replay_tree);
+	return 0;
+}
+
+/**
+ * replay_buds - replay all buds.
+ * @c: UBIFS file-system description object
+ *
+ * This function returns zero in case of success and a negative error code in
+ * case of failure.
+ */
+static int replay_buds(struct ubifs_info *c)
+{
+	struct bud_entry *b;
+	int err, uninitialized_var(free), uninitialized_var(dirty);
+
+	list_for_each_entry(b, &c->replay_buds, list) {
+		err = replay_bud(c, b->bud->lnum, b->bud->start, b->bud->jhead,
+				 &free, &dirty);
+		if (err)
+			return err;
+		err = insert_ref_node(c, b->bud->lnum, b->bud->start, b->sqnum,
+				      free, dirty);
+		if (err)
+			return err;
+	}
+
+	return 0;
+}
+
+/**
+ * destroy_bud_list - destroy the list of buds to replay.
+ * @c: UBIFS file-system description object
+ */
+static void destroy_bud_list(struct ubifs_info *c)
+{
+	struct bud_entry *b;
+
+	while (!list_empty(&c->replay_buds)) {
+		b = list_entry(c->replay_buds.next, struct bud_entry, list);
+		list_del(&b->list);
+		kfree(b);
+	}
+}
+
+/**
+ * add_replay_bud - add a bud to the list of buds to replay.
+ * @c: UBIFS file-system description object
+ * @lnum: bud logical eraseblock number to replay
+ * @offs: bud start offset
+ * @jhead: journal head to which this bud belongs
+ * @sqnum: reference node sequence number
+ *
+ * This function returns zero in case of success and a negative error code in
+ * case of failure.
+ */
+static int add_replay_bud(struct ubifs_info *c, int lnum, int offs, int jhead,
+			  unsigned long long sqnum)
+{
+	struct ubifs_bud *bud;
+	struct bud_entry *b;
+
+	dbg_mnt("add replay bud LEB %d:%d, head %d", lnum, offs, jhead);
+
+	bud = kmalloc(sizeof(struct ubifs_bud), GFP_KERNEL);
+	if (!bud)
+		return -ENOMEM;
+
+	b = kmalloc(sizeof(struct bud_entry), GFP_KERNEL);
+	if (!b) {
+		kfree(bud);
+		return -ENOMEM;
+	}
+
+	bud->lnum = lnum;
+	bud->start = offs;
+	bud->jhead = jhead;
+	ubifs_add_bud(c, bud);
+
+	b->bud = bud;
+	b->sqnum = sqnum;
+	list_add_tail(&b->list, &c->replay_buds);
+
+	return 0;
+}
+
+/**
+ * validate_ref - validate a reference node.
+ * @c: UBIFS file-system description object
+ * @ref: the reference node to validate
+ * @ref_lnum: LEB number of the reference node
+ * @ref_offs: reference node offset
+ *
+ * This function returns %1 if a bud reference already exists for the LEB. %0 is
+ * returned if the reference node is new, otherwise %-EINVAL is returned if
+ * validation failed.
+ */
+static int validate_ref(struct ubifs_info *c, const struct ubifs_ref_node *ref)
+{
+	struct ubifs_bud *bud;
+	int lnum = le32_to_cpu(ref->lnum);
+	unsigned int offs = le32_to_cpu(ref->offs);
+	unsigned int jhead = le32_to_cpu(ref->jhead);
+
+	/*
+	 * ref->offs may point to the end of LEB when the journal head points
+	 * to the end of LEB and we write reference node for it during commit.
+	 * So this is why we require 'offs > c->leb_size'.
+	 */
+	if (jhead >= c->jhead_cnt || lnum >= c->leb_cnt ||
+	    lnum < c->main_first || offs > c->leb_size ||
+	    offs & (c->min_io_size - 1))
+		return -EINVAL;
+
+	/* Make sure we have not already looked at this bud */
+	bud = ubifs_search_bud(c, lnum);
+	if (bud) {
+		if (bud->jhead == jhead && bud->start <= offs)
+			return 1;
+		ubifs_err("bud at LEB %d:%d was already referred", lnum, offs);
+		return -EINVAL;
+	}
+
+	return 0;
+}
+
+/**
+ * replay_log_leb - replay a log logical eraseblock.
+ * @c: UBIFS file-system description object
+ * @lnum: log logical eraseblock to replay
+ * @offs: offset to start replaying from
+ * @sbuf: scan buffer
+ *
+ * This function replays a log LEB and returns zero in case of success, %1 if
+ * this is the last LEB in the log, and a negative error code in case of
+ * failure.
+ */
+static int replay_log_leb(struct ubifs_info *c, int lnum, int offs, void *sbuf)
+{
+	int err;
+	struct ubifs_scan_leb *sleb;
+	struct ubifs_scan_node *snod;
+	const struct ubifs_cs_node *node;
+
+	dbg_mnt("replay log LEB %d:%d", lnum, offs);
+	sleb = ubifs_scan(c, lnum, offs, sbuf);
+	if (IS_ERR(sleb)) {
+		if (c->need_recovery)
+			sleb = ubifs_recover_log_leb(c, lnum, offs, sbuf);
+		if (IS_ERR(sleb))
+			return PTR_ERR(sleb);
+	}
+
+	if (sleb->nodes_cnt == 0) {
+		err = 1;
+		goto out;
+	}
+
+	node = sleb->buf;
+
+	snod = list_entry(sleb->nodes.next, struct ubifs_scan_node, list);
+	if (c->cs_sqnum == 0) {
+		/*
+		 * This is the first log LEB we are looking at, make sure that
+		 * the first node is a commit start node. Also record its
+		 * sequence number so that UBIFS can determine where the log
+		 * ends, because all nodes which were have higher sequence
+		 * numbers.
+		 */
+		if (snod->type != UBIFS_CS_NODE) {
+			dbg_err("first log node at LEB %d:%d is not CS node",
+				lnum, offs);
+			goto out_dump;
+		}
+		if (le64_to_cpu(node->cmt_no) != c->cmt_no) {
+			dbg_err("first CS node at LEB %d:%d has wrong "
+				"commit number %llu expected %llu",
+				lnum, offs,
+				(unsigned long long)le64_to_cpu(node->cmt_no),
+				c->cmt_no);
+			goto out_dump;
+		}
+
+		c->cs_sqnum = le64_to_cpu(node->ch.sqnum);
+		dbg_mnt("commit start sqnum %llu", c->cs_sqnum);
+	}
+
+	if (snod->sqnum < c->cs_sqnum) {
+		/*
+		 * This means that we reached end of log and now
+		 * look to the older log data, which was already
+		 * committed but the eraseblock was not erased (UBIFS
+		 * only unmaps it). So this basically means we have to
+		 * exit with "end of log" code.
+		 */
+		err = 1;
+		goto out;
+	}
+
+	/* Make sure the first node sits at offset zero of the LEB */
+	if (snod->offs != 0) {
+		dbg_err("first node is not at zero offset");
+		goto out_dump;
+	}
+
+	list_for_each_entry(snod, &sleb->nodes, list) {
+
+		cond_resched();
+
+		if (snod->sqnum >= SQNUM_WATERMARK) {
+			ubifs_err("file system's life ended");
+			goto out_dump;
+		}
+
+		if (snod->sqnum < c->cs_sqnum) {
+			dbg_err("bad sqnum %llu, commit sqnum %llu",
+				snod->sqnum, c->cs_sqnum);
+			goto out_dump;
+		}
+
+		if (snod->sqnum > c->max_sqnum)
+			c->max_sqnum = snod->sqnum;
+
+		switch (snod->type) {
+		case UBIFS_REF_NODE: {
+			const struct ubifs_ref_node *ref = snod->node;
+
+			err = validate_ref(c, ref);
+			if (err == 1)
+				break; /* Already have this bud */
+			if (err)
+				goto out_dump;
+
+			err = add_replay_bud(c, le32_to_cpu(ref->lnum),
+					     le32_to_cpu(ref->offs),
+					     le32_to_cpu(ref->jhead),
+					     snod->sqnum);
+			if (err)
+				goto out;
+
+			break;
+		}
+		case UBIFS_CS_NODE:
+			/* Make sure it sits at the beginning of LEB */
+			if (snod->offs != 0) {
+				ubifs_err("unexpected node in log");
+				goto out_dump;
+			}
+			break;
+		default:
+			ubifs_err("unexpected node in log");
+			goto out_dump;
+		}
+	}
+
+	if (sleb->endpt || c->lhead_offs >= c->leb_size) {
+		c->lhead_lnum = lnum;
+		c->lhead_offs = sleb->endpt;
+	}
+
+	err = !sleb->endpt;
+out:
+	ubifs_scan_destroy(sleb);
+	return err;
+
+out_dump:
+	ubifs_err("log error detected while replying the log at LEB %d:%d",
+		  lnum, offs + snod->offs);
+	dbg_dump_node(c, snod->node);
+	ubifs_scan_destroy(sleb);
+	return -EINVAL;
+}
+
+/**
+ * take_ihead - update the status of the index head in lprops to 'taken'.
+ * @c: UBIFS file-system description object
+ *
+ * This function returns the amount of free space in the index head LEB or a
+ * negative error code.
+ */
+static int take_ihead(struct ubifs_info *c)
+{
+	const struct ubifs_lprops *lp;
+	int err, free;
+
+	ubifs_get_lprops(c);
+
+	lp = ubifs_lpt_lookup_dirty(c, c->ihead_lnum);
+	if (IS_ERR(lp)) {
+		err = PTR_ERR(lp);
+		goto out;
+	}
+
+	free = lp->free;
+
+	lp = ubifs_change_lp(c, lp, LPROPS_NC, LPROPS_NC,
+			     lp->flags | LPROPS_TAKEN, 0);
+	if (IS_ERR(lp)) {
+		err = PTR_ERR(lp);
+		goto out;
+	}
+
+	err = free;
+out:
+	ubifs_release_lprops(c);
+	return err;
+}
+
+/**
+ * ubifs_replay_journal - replay journal.
+ * @c: UBIFS file-system description object
+ *
+ * This function scans the journal, replays and cleans it up. It makes sure all
+ * memory data structures related to uncommitted journal are built (dirty TNC
+ * tree, tree of buds, modified lprops, etc).
+ */
+int ubifs_replay_journal(struct ubifs_info *c)
+{
+	int err, i, lnum, offs, free;
+	void *sbuf = NULL;
+
+	BUILD_BUG_ON(UBIFS_TRUN_KEY > 5);
+
+	/* Update the status of the index head in lprops to 'taken' */
+	free = take_ihead(c);
+	if (free < 0)
+		return free; /* Error code */
+
+	if (c->ihead_offs != c->leb_size - free) {
+		ubifs_err("bad index head LEB %d:%d", c->ihead_lnum,
+			  c->ihead_offs);
+		return -EINVAL;
+	}
+
+	sbuf = vmalloc(c->leb_size);
+	if (!sbuf)
+		return -ENOMEM;
+
+	dbg_mnt("start replaying the journal");
+
+	c->replaying = 1;
+
+	lnum = c->ltail_lnum = c->lhead_lnum;
+	offs = c->lhead_offs;
+
+	for (i = 0; i < c->log_lebs; i++, lnum++) {
+		if (lnum >= UBIFS_LOG_LNUM + c->log_lebs) {
+			/*
+			 * The log is logically circular, we reached the last
+			 * LEB, switch to the first one.
+			 */
+			lnum = UBIFS_LOG_LNUM;
+			offs = 0;
+		}
+		err = replay_log_leb(c, lnum, offs, sbuf);
+		if (err == 1)
+			/* We hit the end of the log */
+			break;
+		if (err)
+			goto out;
+		offs = 0;
+	}
+
+	err = replay_buds(c);
+	if (err)
+		goto out;
+
+	err = apply_replay_tree(c);
+	if (err)
+		goto out;
+
+	ubifs_assert(c->bud_bytes <= c->max_bud_bytes || c->need_recovery);
+	dbg_mnt("finished, log head LEB %d:%d, max_sqnum %llu, "
+		"highest_inum %lu", c->lhead_lnum, c->lhead_offs, c->max_sqnum,
+		c->highest_inum);
+out:
+	destroy_replay_tree(c);
+	destroy_bud_list(c);
+	vfree(sbuf);
+	c->replaying = 0;
+	return err;
+}
diff --git a/fs/ubifs/sb.c b/fs/ubifs/sb.c
new file mode 100644
index 00000000000..2bf753b3888
--- /dev/null
+++ b/fs/ubifs/sb.c
@@ -0,0 +1,629 @@
+/*
+ * This file is part of UBIFS.
+ *
+ * Copyright (C) 2006-2008 Nokia Corporation.
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 as published by
+ * the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
+ * more details.
+ *
+ * You should have received a copy of the GNU General Public License along with
+ * this program; if not, write to the Free Software Foundation, Inc., 51
+ * Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
+ *
+ * Authors: Artem Bityutskiy (Битюцкий Артём)
+ *          Adrian Hunter
+ */
+
+/*
+ * This file implements UBIFS superblock. The superblock is stored at the first
+ * LEB of the volume and is never changed by UBIFS. Only user-space tools may
+ * change it. The superblock node mostly contains geometry information.
+ */
+
+#include "ubifs.h"
+#include <linux/random.h>
+
+/*
+ * Default journal size in logical eraseblocks as a percent of total
+ * flash size.
+ */
+#define DEFAULT_JNL_PERCENT 5
+
+/* Default maximum journal size in bytes */
+#define DEFAULT_MAX_JNL (32*1024*1024)
+
+/* Default indexing tree fanout */
+#define DEFAULT_FANOUT 8
+
+/* Default number of data journal heads */
+#define DEFAULT_JHEADS_CNT 1
+
+/* Default positions of different LEBs in the main area */
+#define DEFAULT_IDX_LEB  0
+#define DEFAULT_DATA_LEB 1
+#define DEFAULT_GC_LEB   2
+
+/* Default number of LEB numbers in LPT's save table */
+#define DEFAULT_LSAVE_CNT 256
+
+/* Default reserved pool size as a percent of maximum free space */
+#define DEFAULT_RP_PERCENT 5
+
+/* The default maximum size of reserved pool in bytes */
+#define DEFAULT_MAX_RP_SIZE (5*1024*1024)
+
+/* Default time granularity in nanoseconds */
+#define DEFAULT_TIME_GRAN 1000000000
+
+/**
+ * create_default_filesystem - format empty UBI volume.
+ * @c: UBIFS file-system description object
+ *
+ * This function creates default empty file-system. Returns zero in case of
+ * success and a negative error code in case of failure.
+ */
+static int create_default_filesystem(struct ubifs_info *c)
+{
+	struct ubifs_sb_node *sup;
+	struct ubifs_mst_node *mst;
+	struct ubifs_idx_node *idx;
+	struct ubifs_branch *br;
+	struct ubifs_ino_node *ino;
+	struct ubifs_cs_node *cs;
+	union ubifs_key key;
+	int err, tmp, jnl_lebs, log_lebs, max_buds, main_lebs, main_first;
+	int lpt_lebs, lpt_first, orph_lebs, big_lpt, ino_waste, sup_flags = 0;
+	int min_leb_cnt = UBIFS_MIN_LEB_CNT;
+	uint64_t tmp64, main_bytes;
+
+	/* Some functions called from here depend on the @c->key_len filed */
+	c->key_len = UBIFS_SK_LEN;
+
+	/*
+	 * First of all, we have to calculate default file-system geometry -
+	 * log size, journal size, etc.
+	 */
+	if (c->leb_cnt < 0x7FFFFFFF / DEFAULT_JNL_PERCENT)
+		/* We can first multiply then divide and have no overflow */
+		jnl_lebs = c->leb_cnt * DEFAULT_JNL_PERCENT / 100;
+	else
+		jnl_lebs = (c->leb_cnt / 100) * DEFAULT_JNL_PERCENT;
+
+	if (jnl_lebs < UBIFS_MIN_JNL_LEBS)
+		jnl_lebs = UBIFS_MIN_JNL_LEBS;
+	if (jnl_lebs * c->leb_size > DEFAULT_MAX_JNL)
+		jnl_lebs = DEFAULT_MAX_JNL / c->leb_size;
+
+	/*
+	 * The log should be large enough to fit reference nodes for all bud
+	 * LEBs. Because buds do not have to start from the beginning of LEBs
+	 * (half of the LEB may contain committed data), the log should
+	 * generally be larger, make it twice as large.
+	 */
+	tmp = 2 * (c->ref_node_alsz * jnl_lebs) + c->leb_size - 1;
+	log_lebs = tmp / c->leb_size;
+	/* Plus one LEB reserved for commit */
+	log_lebs += 1;
+	if (c->leb_cnt - min_leb_cnt > 8) {
+		/* And some extra space to allow writes while committing */
+		log_lebs += 1;
+		min_leb_cnt += 1;
+	}
+
+	max_buds = jnl_lebs - log_lebs;
+	if (max_buds < UBIFS_MIN_BUD_LEBS)
+		max_buds = UBIFS_MIN_BUD_LEBS;
+
+	/*
+	 * Orphan nodes are stored in a separate area. One node can store a lot
+	 * of orphan inode numbers, but when new orphan comes we just add a new
+	 * orphan node. At some point the nodes are consolidated into one
+	 * orphan node.
+	 */
+	orph_lebs = UBIFS_MIN_ORPH_LEBS;
+#ifdef CONFIG_UBIFS_FS_DEBUG
+	if (c->leb_cnt - min_leb_cnt > 1)
+		/*
+		 * For debugging purposes it is better to have at least 2
+		 * orphan LEBs, because the orphan subsystem would need to do
+		 * consolidations and would be stressed more.
+		 */
+		orph_lebs += 1;
+#endif
+
+	main_lebs = c->leb_cnt - UBIFS_SB_LEBS - UBIFS_MST_LEBS - log_lebs;
+	main_lebs -= orph_lebs;
+
+	lpt_first = UBIFS_LOG_LNUM + log_lebs;
+	c->lsave_cnt = DEFAULT_LSAVE_CNT;
+	c->max_leb_cnt = c->leb_cnt;
+	err = ubifs_create_dflt_lpt(c, &main_lebs, lpt_first, &lpt_lebs,
+				    &big_lpt);
+	if (err)
+		return err;
+
+	dbg_gen("LEB Properties Tree created (LEBs %d-%d)", lpt_first,
+		lpt_first + lpt_lebs - 1);
+
+	main_first = c->leb_cnt - main_lebs;
+
+	/* Create default superblock */
+	tmp = ALIGN(UBIFS_SB_NODE_SZ, c->min_io_size);
+	sup = kzalloc(tmp, GFP_KERNEL);
+	if (!sup)
+		return -ENOMEM;
+
+	tmp64 = (uint64_t)max_buds * c->leb_size;
+	if (big_lpt)
+		sup_flags |= UBIFS_FLG_BIGLPT;
+
+	sup->ch.node_type  = UBIFS_SB_NODE;
+	sup->key_hash      = UBIFS_KEY_HASH_R5;
+	sup->flags         = cpu_to_le32(sup_flags);
+	sup->min_io_size   = cpu_to_le32(c->min_io_size);
+	sup->leb_size      = cpu_to_le32(c->leb_size);
+	sup->leb_cnt       = cpu_to_le32(c->leb_cnt);
+	sup->max_leb_cnt   = cpu_to_le32(c->max_leb_cnt);
+	sup->max_bud_bytes = cpu_to_le64(tmp64);
+	sup->log_lebs      = cpu_to_le32(log_lebs);
+	sup->lpt_lebs      = cpu_to_le32(lpt_lebs);
+	sup->orph_lebs     = cpu_to_le32(orph_lebs);
+	sup->jhead_cnt     = cpu_to_le32(DEFAULT_JHEADS_CNT);
+	sup->fanout        = cpu_to_le32(DEFAULT_FANOUT);
+	sup->lsave_cnt     = cpu_to_le32(c->lsave_cnt);
+	sup->fmt_version   = cpu_to_le32(UBIFS_FORMAT_VERSION);
+	sup->default_compr = cpu_to_le16(UBIFS_COMPR_LZO);
+	sup->time_gran     = cpu_to_le32(DEFAULT_TIME_GRAN);
+
+	generate_random_uuid(sup->uuid);
+
+	main_bytes = (uint64_t)main_lebs * c->leb_size;
+	tmp64 = main_bytes * DEFAULT_RP_PERCENT;
+	do_div(tmp64, 100);
+	if (tmp64 > DEFAULT_MAX_RP_SIZE)
+		tmp64 = DEFAULT_MAX_RP_SIZE;
+	sup->rp_size = cpu_to_le64(tmp64);
+
+	err = ubifs_write_node(c, sup, UBIFS_SB_NODE_SZ, 0, 0, UBI_LONGTERM);
+	kfree(sup);
+	if (err)
+		return err;
+
+	dbg_gen("default superblock created at LEB 0:0");
+
+	/* Create default master node */
+	mst = kzalloc(c->mst_node_alsz, GFP_KERNEL);
+	if (!mst)
+		return -ENOMEM;
+
+	mst->ch.node_type = UBIFS_MST_NODE;
+	mst->log_lnum     = cpu_to_le32(UBIFS_LOG_LNUM);
+	mst->highest_inum = cpu_to_le64(UBIFS_FIRST_INO);
+	mst->cmt_no       = 0;
+	mst->root_lnum    = cpu_to_le32(main_first + DEFAULT_IDX_LEB);
+	mst->root_offs    = 0;
+	tmp = ubifs_idx_node_sz(c, 1);
+	mst->root_len     = cpu_to_le32(tmp);
+	mst->gc_lnum      = cpu_to_le32(main_first + DEFAULT_GC_LEB);
+	mst->ihead_lnum   = cpu_to_le32(main_first + DEFAULT_IDX_LEB);
+	mst->ihead_offs   = cpu_to_le32(ALIGN(tmp, c->min_io_size));
+	mst->index_size   = cpu_to_le64(ALIGN(tmp, 8));
+	mst->lpt_lnum     = cpu_to_le32(c->lpt_lnum);
+	mst->lpt_offs     = cpu_to_le32(c->lpt_offs);
+	mst->nhead_lnum   = cpu_to_le32(c->nhead_lnum);
+	mst->nhead_offs   = cpu_to_le32(c->nhead_offs);
+	mst->ltab_lnum    = cpu_to_le32(c->ltab_lnum);
+	mst->ltab_offs    = cpu_to_le32(c->ltab_offs);
+	mst->lsave_lnum   = cpu_to_le32(c->lsave_lnum);
+	mst->lsave_offs   = cpu_to_le32(c->lsave_offs);
+	mst->lscan_lnum   = cpu_to_le32(main_first);
+	mst->empty_lebs   = cpu_to_le32(main_lebs - 2);
+	mst->idx_lebs     = cpu_to_le32(1);
+	mst->leb_cnt      = cpu_to_le32(c->leb_cnt);
+
+	/* Calculate lprops statistics */
+	tmp64 = main_bytes;
+	tmp64 -= ALIGN(ubifs_idx_node_sz(c, 1), c->min_io_size);
+	tmp64 -= ALIGN(UBIFS_INO_NODE_SZ, c->min_io_size);
+	mst->total_free = cpu_to_le64(tmp64);
+
+	tmp64 = ALIGN(ubifs_idx_node_sz(c, 1), c->min_io_size);
+	ino_waste = ALIGN(UBIFS_INO_NODE_SZ, c->min_io_size) -
+			  UBIFS_INO_NODE_SZ;
+	tmp64 += ino_waste;
+	tmp64 -= ALIGN(ubifs_idx_node_sz(c, 1), 8);
+	mst->total_dirty = cpu_to_le64(tmp64);
+
+	/*  The indexing LEB does not contribute to dark space */
+	tmp64 = (c->main_lebs - 1) * c->dark_wm;
+	mst->total_dark = cpu_to_le64(tmp64);
+
+	mst->total_used = cpu_to_le64(UBIFS_INO_NODE_SZ);
+
+	err = ubifs_write_node(c, mst, UBIFS_MST_NODE_SZ, UBIFS_MST_LNUM, 0,
+			       UBI_UNKNOWN);
+	if (err) {
+		kfree(mst);
+		return err;
+	}
+	err = ubifs_write_node(c, mst, UBIFS_MST_NODE_SZ, UBIFS_MST_LNUM + 1, 0,
+			       UBI_UNKNOWN);
+	kfree(mst);
+	if (err)
+		return err;
+
+	dbg_gen("default master node created at LEB %d:0", UBIFS_MST_LNUM);
+
+	/* Create the root indexing node */
+	tmp = ubifs_idx_node_sz(c, 1);
+	idx = kzalloc(ALIGN(tmp, c->min_io_size), GFP_KERNEL);
+	if (!idx)
+		return -ENOMEM;
+
+	c->key_fmt = UBIFS_SIMPLE_KEY_FMT;
+	c->key_hash = key_r5_hash;
+
+	idx->ch.node_type = UBIFS_IDX_NODE;
+	idx->child_cnt = cpu_to_le16(1);
+	ino_key_init(c, &key, UBIFS_ROOT_INO);
+	br = ubifs_idx_branch(c, idx, 0);
+	key_write_idx(c, &key, &br->key);
+	br->lnum = cpu_to_le32(main_first + DEFAULT_DATA_LEB);
+	br->len  = cpu_to_le32(UBIFS_INO_NODE_SZ);
+	err = ubifs_write_node(c, idx, tmp, main_first + DEFAULT_IDX_LEB, 0,
+			       UBI_UNKNOWN);
+	kfree(idx);
+	if (err)
+		return err;
+
+	dbg_gen("default root indexing node created LEB %d:0",
+		main_first + DEFAULT_IDX_LEB);
+
+	/* Create default root inode */
+	tmp = ALIGN(UBIFS_INO_NODE_SZ, c->min_io_size);
+	ino = kzalloc(tmp, GFP_KERNEL);
+	if (!ino)
+		return -ENOMEM;
+
+	ino_key_init_flash(c, &ino->key, UBIFS_ROOT_INO);
+	ino->ch.node_type = UBIFS_INO_NODE;
+	ino->creat_sqnum = cpu_to_le64(++c->max_sqnum);
+	ino->nlink = cpu_to_le32(2);
+	tmp = cpu_to_le64(CURRENT_TIME_SEC.tv_sec);
+	ino->atime_sec   = tmp;
+	ino->ctime_sec   = tmp;
+	ino->mtime_sec   = tmp;
+	ino->atime_nsec  = 0;
+	ino->ctime_nsec  = 0;
+	ino->mtime_nsec  = 0;
+	ino->mode = cpu_to_le32(S_IFDIR | S_IRUGO | S_IWUSR | S_IXUGO);
+	ino->size = cpu_to_le64(UBIFS_INO_NODE_SZ);
+
+	/* Set compression enabled by default */
+	ino->flags = cpu_to_le32(UBIFS_COMPR_FL);
+
+	err = ubifs_write_node(c, ino, UBIFS_INO_NODE_SZ,
+			       main_first + DEFAULT_DATA_LEB, 0,
+			       UBI_UNKNOWN);
+	kfree(ino);
+	if (err)
+		return err;
+
+	dbg_gen("root inode created at LEB %d:0",
+		main_first + DEFAULT_DATA_LEB);
+
+	/*
+	 * The first node in the log has to be the commit start node. This is
+	 * always the case during normal file-system operation. Write a fake
+	 * commit start node to the log.
+	 */
+	tmp = ALIGN(UBIFS_CS_NODE_SZ, c->min_io_size);
+	cs = kzalloc(tmp, GFP_KERNEL);
+	if (!cs)
+		return -ENOMEM;
+
+	cs->ch.node_type = UBIFS_CS_NODE;
+	err = ubifs_write_node(c, cs, UBIFS_CS_NODE_SZ, UBIFS_LOG_LNUM,
+			       0, UBI_UNKNOWN);
+	kfree(cs);
+
+	ubifs_msg("default file-system created");
+	return 0;
+}
+
+/**
+ * validate_sb - validate superblock node.
+ * @c: UBIFS file-system description object
+ * @sup: superblock node
+ *
+ * This function validates superblock node @sup. Since most of data was read
+ * from the superblock and stored in @c, the function validates fields in @c
+ * instead. Returns zero in case of success and %-EINVAL in case of validation
+ * failure.
+ */
+static int validate_sb(struct ubifs_info *c, struct ubifs_sb_node *sup)
+{
+	long long max_bytes;
+	int err = 1, min_leb_cnt;
+
+	if (!c->key_hash) {
+		err = 2;
+		goto failed;
+	}
+
+	if (sup->key_fmt != UBIFS_SIMPLE_KEY_FMT) {
+		err = 3;
+		goto failed;
+	}
+
+	if (le32_to_cpu(sup->min_io_size) != c->min_io_size) {
+		ubifs_err("min. I/O unit mismatch: %d in superblock, %d real",
+			  le32_to_cpu(sup->min_io_size), c->min_io_size);
+		goto failed;
+	}
+
+	if (le32_to_cpu(sup->leb_size) != c->leb_size) {
+		ubifs_err("LEB size mismatch: %d in superblock, %d real",
+			  le32_to_cpu(sup->leb_size), c->leb_size);
+		goto failed;
+	}
+
+	if (c->log_lebs < UBIFS_MIN_LOG_LEBS ||
+	    c->lpt_lebs < UBIFS_MIN_LPT_LEBS ||
+	    c->orph_lebs < UBIFS_MIN_ORPH_LEBS ||
+	    c->main_lebs < UBIFS_MIN_MAIN_LEBS) {
+		err = 4;
+		goto failed;
+	}
+
+	/*
+	 * Calculate minimum allowed amount of main area LEBs. This is very
+	 * similar to %UBIFS_MIN_LEB_CNT, but we take into account real what we
+	 * have just read from the superblock.
+	 */
+	min_leb_cnt = UBIFS_SB_LEBS + UBIFS_MST_LEBS + c->log_lebs;
+	min_leb_cnt += c->lpt_lebs + c->orph_lebs + c->jhead_cnt + 6;
+
+	if (c->leb_cnt < min_leb_cnt || c->leb_cnt > c->vi.size) {
+		ubifs_err("bad LEB count: %d in superblock, %d on UBI volume, "
+			  "%d minimum required", c->leb_cnt, c->vi.size,
+			  min_leb_cnt);
+		goto failed;
+	}
+
+	if (c->max_leb_cnt < c->leb_cnt) {
+		ubifs_err("max. LEB count %d less than LEB count %d",
+			  c->max_leb_cnt, c->leb_cnt);
+		goto failed;
+	}
+
+	if (c->main_lebs < UBIFS_MIN_MAIN_LEBS) {
+		err = 7;
+		goto failed;
+	}
+
+	if (c->max_bud_bytes < (long long)c->leb_size * UBIFS_MIN_BUD_LEBS ||
+	    c->max_bud_bytes > (long long)c->leb_size * c->main_lebs) {
+		err = 8;
+		goto failed;
+	}
+
+	if (c->jhead_cnt < NONDATA_JHEADS_CNT + 1 ||
+	    c->jhead_cnt > NONDATA_JHEADS_CNT + UBIFS_MAX_JHEADS) {
+		err = 9;
+		goto failed;
+	}
+
+	if (c->fanout < UBIFS_MIN_FANOUT ||
+	    ubifs_idx_node_sz(c, c->fanout) > c->leb_size) {
+		err = 10;
+		goto failed;
+	}
+
+	if (c->lsave_cnt < 0 || (c->lsave_cnt > DEFAULT_LSAVE_CNT &&
+	    c->lsave_cnt > c->max_leb_cnt - UBIFS_SB_LEBS - UBIFS_MST_LEBS -
+	    c->log_lebs - c->lpt_lebs - c->orph_lebs)) {
+		err = 11;
+		goto failed;
+	}
+
+	if (UBIFS_SB_LEBS + UBIFS_MST_LEBS + c->log_lebs + c->lpt_lebs +
+	    c->orph_lebs + c->main_lebs != c->leb_cnt) {
+		err = 12;
+		goto failed;
+	}
+
+	if (c->default_compr < 0 || c->default_compr >= UBIFS_COMPR_TYPES_CNT) {
+		err = 13;
+		goto failed;
+	}
+
+	max_bytes = c->main_lebs * (long long)c->leb_size;
+	if (c->rp_size < 0 || max_bytes < c->rp_size) {
+		err = 14;
+		goto failed;
+	}
+
+	if (le32_to_cpu(sup->time_gran) > 1000000000 ||
+	    le32_to_cpu(sup->time_gran) < 1) {
+		err = 15;
+		goto failed;
+	}
+
+	return 0;
+
+failed:
+	ubifs_err("bad superblock, error %d", err);
+	dbg_dump_node(c, sup);
+	return -EINVAL;
+}
+
+/**
+ * ubifs_read_sb_node - read superblock node.
+ * @c: UBIFS file-system description object
+ *
+ * This function returns a pointer to the superblock node or a negative error
+ * code.
+ */
+struct ubifs_sb_node *ubifs_read_sb_node(struct ubifs_info *c)
+{
+	struct ubifs_sb_node *sup;
+	int err;
+
+	sup = kmalloc(ALIGN(UBIFS_SB_NODE_SZ, c->min_io_size), GFP_NOFS);
+	if (!sup)
+		return ERR_PTR(-ENOMEM);
+
+	err = ubifs_read_node(c, sup, UBIFS_SB_NODE, UBIFS_SB_NODE_SZ,
+			      UBIFS_SB_LNUM, 0);
+	if (err) {
+		kfree(sup);
+		return ERR_PTR(err);
+	}
+
+	return sup;
+}
+
+/**
+ * ubifs_write_sb_node - write superblock node.
+ * @c: UBIFS file-system description object
+ * @sup: superblock node read with 'ubifs_read_sb_node()'
+ *
+ * This function returns %0 on success and a negative error code on failure.
+ */
+int ubifs_write_sb_node(struct ubifs_info *c, struct ubifs_sb_node *sup)
+{
+	int len = ALIGN(UBIFS_SB_NODE_SZ, c->min_io_size);
+
+	ubifs_prepare_node(c, sup, UBIFS_SB_NODE_SZ, 1);
+	return ubifs_leb_change(c, UBIFS_SB_LNUM, sup, len, UBI_LONGTERM);
+}
+
+/**
+ * ubifs_read_superblock - read superblock.
+ * @c: UBIFS file-system description object
+ *
+ * This function finds, reads and checks the superblock. If an empty UBI volume
+ * is being mounted, this function creates default superblock. Returns zero in
+ * case of success, and a negative error code in case of failure.
+ */
+int ubifs_read_superblock(struct ubifs_info *c)
+{
+	int err, sup_flags;
+	struct ubifs_sb_node *sup;
+
+	if (c->empty) {
+		err = create_default_filesystem(c);
+		if (err)
+			return err;
+	}
+
+	sup = ubifs_read_sb_node(c);
+	if (IS_ERR(sup))
+		return PTR_ERR(sup);
+
+	/*
+	 * The software supports all previous versions but not future versions,
+	 * due to the unavailability of time-travelling equipment.
+	 */
+	c->fmt_version = le32_to_cpu(sup->fmt_version);
+	if (c->fmt_version > UBIFS_FORMAT_VERSION) {
+		ubifs_err("on-flash format version is %d, but software only "
+			  "supports up to version %d", c->fmt_version,
+			  UBIFS_FORMAT_VERSION);
+		err = -EINVAL;
+		goto out;
+	}
+
+	if (c->fmt_version < 3) {
+		ubifs_err("on-flash format version %d is not supported",
+			  c->fmt_version);
+		err = -EINVAL;
+		goto out;
+	}
+
+	switch (sup->key_hash) {
+	case UBIFS_KEY_HASH_R5:
+		c->key_hash = key_r5_hash;
+		c->key_hash_type = UBIFS_KEY_HASH_R5;
+		break;
+
+	case UBIFS_KEY_HASH_TEST:
+		c->key_hash = key_test_hash;
+		c->key_hash_type = UBIFS_KEY_HASH_TEST;
+		break;
+	};
+
+	c->key_fmt = sup->key_fmt;
+
+	switch (c->key_fmt) {
+	case UBIFS_SIMPLE_KEY_FMT:
+		c->key_len = UBIFS_SK_LEN;
+		break;
+	default:
+		ubifs_err("unsupported key format");
+		err = -EINVAL;
+		goto out;
+	}
+
+	c->leb_cnt       = le32_to_cpu(sup->leb_cnt);
+	c->max_leb_cnt   = le32_to_cpu(sup->max_leb_cnt);
+	c->max_bud_bytes = le64_to_cpu(sup->max_bud_bytes);
+	c->log_lebs      = le32_to_cpu(sup->log_lebs);
+	c->lpt_lebs      = le32_to_cpu(sup->lpt_lebs);
+	c->orph_lebs     = le32_to_cpu(sup->orph_lebs);
+	c->jhead_cnt     = le32_to_cpu(sup->jhead_cnt) + NONDATA_JHEADS_CNT;
+	c->fanout        = le32_to_cpu(sup->fanout);
+	c->lsave_cnt     = le32_to_cpu(sup->lsave_cnt);
+	c->default_compr = le16_to_cpu(sup->default_compr);
+	c->rp_size       = le64_to_cpu(sup->rp_size);
+	c->rp_uid        = le32_to_cpu(sup->rp_uid);
+	c->rp_gid        = le32_to_cpu(sup->rp_gid);
+	sup_flags        = le32_to_cpu(sup->flags);
+
+	c->vfs_sb->s_time_gran = le32_to_cpu(sup->time_gran);
+
+	memcpy(&c->uuid, &sup->uuid, 16);
+
+	c->big_lpt = !!(sup_flags & UBIFS_FLG_BIGLPT);
+
+	/* Automatically increase file system size to the maximum size */
+	c->old_leb_cnt = c->leb_cnt;
+	if (c->leb_cnt < c->vi.size && c->leb_cnt < c->max_leb_cnt) {
+		c->leb_cnt = min_t(int, c->max_leb_cnt, c->vi.size);
+		if (c->vfs_sb->s_flags & MS_RDONLY)
+			dbg_mnt("Auto resizing (ro) from %d LEBs to %d LEBs",
+				c->old_leb_cnt,	c->leb_cnt);
+		else {
+			dbg_mnt("Auto resizing (sb) from %d LEBs to %d LEBs",
+				c->old_leb_cnt, c->leb_cnt);
+			sup->leb_cnt = cpu_to_le32(c->leb_cnt);
+			err = ubifs_write_sb_node(c, sup);
+			if (err)
+				goto out;
+			c->old_leb_cnt = c->leb_cnt;
+		}
+	}
+
+	c->log_bytes = (long long)c->log_lebs * c->leb_size;
+	c->log_last = UBIFS_LOG_LNUM + c->log_lebs - 1;
+	c->lpt_first = UBIFS_LOG_LNUM + c->log_lebs;
+	c->lpt_last = c->lpt_first + c->lpt_lebs - 1;
+	c->orph_first = c->lpt_last + 1;
+	c->orph_last = c->orph_first + c->orph_lebs - 1;
+	c->main_lebs = c->leb_cnt - UBIFS_SB_LEBS - UBIFS_MST_LEBS;
+	c->main_lebs -= c->log_lebs + c->lpt_lebs + c->orph_lebs;
+	c->main_first = c->leb_cnt - c->main_lebs;
+	c->report_rp_size = ubifs_reported_space(c, c->rp_size);
+
+	err = validate_sb(c, sup);
+out:
+	kfree(sup);
+	return err;
+}
diff --git a/fs/ubifs/scan.c b/fs/ubifs/scan.c
new file mode 100644
index 00000000000..acf5c5fffc6
--- /dev/null
+++ b/fs/ubifs/scan.c
@@ -0,0 +1,362 @@
+/*
+ * This file is part of UBIFS.
+ *
+ * Copyright (C) 2006-2008 Nokia Corporation
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 as published by
+ * the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
+ * more details.
+ *
+ * You should have received a copy of the GNU General Public License along with
+ * this program; if not, write to the Free Software Foundation, Inc., 51
+ * Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
+ *
+ * Authors: Adrian Hunter
+ *          Artem Bityutskiy (Битюцкий Артём)
+ */
+
+/*
+ * This file implements the scan which is a general-purpose function for
+ * determining what nodes are in an eraseblock. The scan is used to replay the
+ * journal, to do garbage collection. for the TNC in-the-gaps method, and by
+ * debugging functions.
+ */
+
+#include "ubifs.h"
+
+/**
+ * scan_padding_bytes - scan for padding bytes.
+ * @buf: buffer to scan
+ * @len: length of buffer
+ *
+ * This function returns the number of padding bytes on success and
+ * %SCANNED_GARBAGE on failure.
+ */
+static int scan_padding_bytes(void *buf, int len)
+{
+	int pad_len = 0, max_pad_len = min_t(int, UBIFS_PAD_NODE_SZ, len);
+	uint8_t *p = buf;
+
+	dbg_scan("not a node");
+
+	while (pad_len < max_pad_len && *p++ == UBIFS_PADDING_BYTE)
+		pad_len += 1;
+
+	if (!pad_len || (pad_len & 7))
+		return SCANNED_GARBAGE;
+
+	dbg_scan("%d padding bytes", pad_len);
+
+	return pad_len;
+}
+
+/**
+ * ubifs_scan_a_node - scan for a node or padding.
+ * @c: UBIFS file-system description object
+ * @buf: buffer to scan
+ * @len: length of buffer
+ * @lnum: logical eraseblock number
+ * @offs: offset within the logical eraseblock
+ * @quiet: print no messages
+ *
+ * This function returns a scanning code to indicate what was scanned.
+ */
+int ubifs_scan_a_node(const struct ubifs_info *c, void *buf, int len, int lnum,
+		      int offs, int quiet)
+{
+	struct ubifs_ch *ch = buf;
+	uint32_t magic;
+
+	magic = le32_to_cpu(ch->magic);
+
+	if (magic == 0xFFFFFFFF) {
+		dbg_scan("hit empty space");
+		return SCANNED_EMPTY_SPACE;
+	}
+
+	if (magic != UBIFS_NODE_MAGIC)
+		return scan_padding_bytes(buf, len);
+
+	if (len < UBIFS_CH_SZ)
+		return SCANNED_GARBAGE;
+
+	dbg_scan("scanning %s", dbg_ntype(ch->node_type));
+
+	if (ubifs_check_node(c, buf, lnum, offs, quiet))
+		return SCANNED_A_CORRUPT_NODE;
+
+	if (ch->node_type == UBIFS_PAD_NODE) {
+		struct ubifs_pad_node *pad = buf;
+		int pad_len = le32_to_cpu(pad->pad_len);
+		int node_len = le32_to_cpu(ch->len);
+
+		/* Validate the padding node */
+		if (pad_len < 0 ||
+		    offs + node_len + pad_len > c->leb_size) {
+			if (!quiet) {
+				ubifs_err("bad pad node at LEB %d:%d",
+					  lnum, offs);
+				dbg_dump_node(c, pad);
+			}
+			return SCANNED_A_BAD_PAD_NODE;
+		}
+
+		/* Make the node pads to 8-byte boundary */
+		if ((node_len + pad_len) & 7) {
+			if (!quiet) {
+				dbg_err("bad padding length %d - %d",
+					offs, offs + node_len + pad_len);
+			}
+			return SCANNED_A_BAD_PAD_NODE;
+		}
+
+		dbg_scan("%d bytes padded, offset now %d",
+			 pad_len, ALIGN(offs + node_len + pad_len, 8));
+
+		return node_len + pad_len;
+	}
+
+	return SCANNED_A_NODE;
+}
+
+/**
+ * ubifs_start_scan - create LEB scanning information at start of scan.
+ * @c: UBIFS file-system description object
+ * @lnum: logical eraseblock number
+ * @offs: offset to start at (usually zero)
+ * @sbuf: scan buffer (must be c->leb_size)
+ *
+ * This function returns %0 on success and a negative error code on failure.
+ */
+struct ubifs_scan_leb *ubifs_start_scan(const struct ubifs_info *c, int lnum,
+					int offs, void *sbuf)
+{
+	struct ubifs_scan_leb *sleb;
+	int err;
+
+	dbg_scan("scan LEB %d:%d", lnum, offs);
+
+	sleb = kzalloc(sizeof(struct ubifs_scan_leb), GFP_NOFS);
+	if (!sleb)
+		return ERR_PTR(-ENOMEM);
+
+	sleb->lnum = lnum;
+	INIT_LIST_HEAD(&sleb->nodes);
+	sleb->buf = sbuf;
+
+	err = ubi_read(c->ubi, lnum, sbuf + offs, offs, c->leb_size - offs);
+	if (err && err != -EBADMSG) {
+		ubifs_err("cannot read %d bytes from LEB %d:%d,"
+			  " error %d", c->leb_size - offs, lnum, offs, err);
+		kfree(sleb);
+		return ERR_PTR(err);
+	}
+
+	if (err == -EBADMSG)
+		sleb->ecc = 1;
+
+	return sleb;
+}
+
+/**
+ * ubifs_end_scan - update LEB scanning information at end of scan.
+ * @c: UBIFS file-system description object
+ * @sleb: scanning information
+ * @lnum: logical eraseblock number
+ * @offs: offset to start at (usually zero)
+ *
+ * This function returns %0 on success and a negative error code on failure.
+ */
+void ubifs_end_scan(const struct ubifs_info *c, struct ubifs_scan_leb *sleb,
+		    int lnum, int offs)
+{
+	lnum = lnum;
+	dbg_scan("stop scanning LEB %d at offset %d", lnum, offs);
+	ubifs_assert(offs % c->min_io_size == 0);
+
+	sleb->endpt = ALIGN(offs, c->min_io_size);
+}
+
+/**
+ * ubifs_add_snod - add a scanned node to LEB scanning information.
+ * @c: UBIFS file-system description object
+ * @sleb: scanning information
+ * @buf: buffer containing node
+ * @offs: offset of node on flash
+ *
+ * This function returns %0 on success and a negative error code on failure.
+ */
+int ubifs_add_snod(const struct ubifs_info *c, struct ubifs_scan_leb *sleb,
+		   void *buf, int offs)
+{
+	struct ubifs_ch *ch = buf;
+	struct ubifs_ino_node *ino = buf;
+	struct ubifs_scan_node *snod;
+
+	snod = kzalloc(sizeof(struct ubifs_scan_node), GFP_NOFS);
+	if (!snod)
+		return -ENOMEM;
+
+	snod->sqnum = le64_to_cpu(ch->sqnum);
+	snod->type = ch->node_type;
+	snod->offs = offs;
+	snod->len = le32_to_cpu(ch->len);
+	snod->node = buf;
+
+	switch (ch->node_type) {
+	case UBIFS_INO_NODE:
+	case UBIFS_DENT_NODE:
+	case UBIFS_XENT_NODE:
+	case UBIFS_DATA_NODE:
+	case UBIFS_TRUN_NODE:
+		/*
+		 * The key is in the same place in all keyed
+		 * nodes.
+		 */
+		key_read(c, &ino->key, &snod->key);
+		break;
+	}
+	list_add_tail(&snod->list, &sleb->nodes);
+	sleb->nodes_cnt += 1;
+	return 0;
+}
+
+/**
+ * ubifs_scanned_corruption - print information after UBIFS scanned corruption.
+ * @c: UBIFS file-system description object
+ * @lnum: LEB number of corruption
+ * @offs: offset of corruption
+ * @buf: buffer containing corruption
+ */
+void ubifs_scanned_corruption(const struct ubifs_info *c, int lnum, int offs,
+			      void *buf)
+{
+	int len;
+
+	ubifs_err("corrupted data at LEB %d:%d", lnum, offs);
+	if (dbg_failure_mode)
+		return;
+	len = c->leb_size - offs;
+	if (len > 4096)
+		len = 4096;
+	dbg_err("first %d bytes from LEB %d:%d", len, lnum, offs);
+	print_hex_dump(KERN_DEBUG, "", DUMP_PREFIX_OFFSET, 32, 4, buf, len, 1);
+}
+
+/**
+ * ubifs_scan - scan a logical eraseblock.
+ * @c: UBIFS file-system description object
+ * @lnum: logical eraseblock number
+ * @offs: offset to start at (usually zero)
+ * @sbuf: scan buffer (must be c->leb_size)
+ *
+ * This function scans LEB number @lnum and returns complete information about
+ * its contents. Returns an error code in case of failure.
+ */
+struct ubifs_scan_leb *ubifs_scan(const struct ubifs_info *c, int lnum,
+				  int offs, void *sbuf)
+{
+	void *buf = sbuf + offs;
+	int err, len = c->leb_size - offs;
+	struct ubifs_scan_leb *sleb;
+
+	sleb = ubifs_start_scan(c, lnum, offs, sbuf);
+	if (IS_ERR(sleb))
+		return sleb;
+
+	while (len >= 8) {
+		struct ubifs_ch *ch = buf;
+		int node_len, ret;
+
+		dbg_scan("look at LEB %d:%d (%d bytes left)",
+			 lnum, offs, len);
+
+		cond_resched();
+
+		ret = ubifs_scan_a_node(c, buf, len, lnum, offs, 0);
+
+		if (ret > 0) {
+			/* Padding bytes or a valid padding node */
+			offs += ret;
+			buf += ret;
+			len -= ret;
+			continue;
+		}
+
+		if (ret == SCANNED_EMPTY_SPACE)
+			/* Empty space is checked later */
+			break;
+
+		switch (ret) {
+		case SCANNED_GARBAGE:
+			dbg_err("garbage");
+			goto corrupted;
+		case SCANNED_A_NODE:
+			break;
+		case SCANNED_A_CORRUPT_NODE:
+		case SCANNED_A_BAD_PAD_NODE:
+			dbg_err("bad node");
+			goto corrupted;
+		default:
+			dbg_err("unknown");
+			goto corrupted;
+		}
+
+		err = ubifs_add_snod(c, sleb, buf, offs);
+		if (err)
+			goto error;
+
+		node_len = ALIGN(le32_to_cpu(ch->len), 8);
+		offs += node_len;
+		buf += node_len;
+		len -= node_len;
+	}
+
+	if (offs % c->min_io_size)
+		goto corrupted;
+
+	ubifs_end_scan(c, sleb, lnum, offs);
+
+	for (; len > 4; offs += 4, buf = buf + 4, len -= 4)
+		if (*(uint32_t *)buf != 0xffffffff)
+			break;
+	for (; len; offs++, buf++, len--)
+		if (*(uint8_t *)buf != 0xff) {
+			ubifs_err("corrupt empty space at LEB %d:%d",
+				  lnum, offs);
+			goto corrupted;
+		}
+
+	return sleb;
+
+corrupted:
+	ubifs_scanned_corruption(c, lnum, offs, buf);
+	err = -EUCLEAN;
+error:
+	ubifs_err("LEB %d scanning failed", lnum);
+	ubifs_scan_destroy(sleb);
+	return ERR_PTR(err);
+}
+
+/**
+ * ubifs_scan_destroy - destroy LEB scanning information.
+ * @sleb: scanning information to free
+ */
+void ubifs_scan_destroy(struct ubifs_scan_leb *sleb)
+{
+	struct ubifs_scan_node *node;
+	struct list_head *head;
+
+	head = &sleb->nodes;
+	while (!list_empty(head)) {
+		node = list_entry(head->next, struct ubifs_scan_node, list);
+		list_del(&node->list);
+		kfree(node);
+	}
+	kfree(sleb);
+}
diff --git a/fs/ubifs/shrinker.c b/fs/ubifs/shrinker.c
new file mode 100644
index 00000000000..f248533841a
--- /dev/null
+++ b/fs/ubifs/shrinker.c
@@ -0,0 +1,322 @@
+/*
+ * This file is part of UBIFS.
+ *
+ * Copyright (C) 2006-2008 Nokia Corporation.
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 as published by
+ * the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
+ * more details.
+ *
+ * You should have received a copy of the GNU General Public License along with
+ * this program; if not, write to the Free Software Foundation, Inc., 51
+ * Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
+ *
+ * Authors: Artem Bityutskiy (Битюцкий Артём)
+ *          Adrian Hunter
+ */
+
+/*
+ * This file implements UBIFS shrinker which evicts clean znodes from the TNC
+ * tree when Linux VM needs more RAM.
+ *
+ * We do not implement any LRU lists to find oldest znodes to free because it
+ * would add additional overhead to the file system fast paths. So the shrinker
+ * just walks the TNC tree when searching for znodes to free.
+ *
+ * If the root of a TNC sub-tree is clean and old enough, then the children are
+ * also clean and old enough. So the shrinker walks the TNC in level order and
+ * dumps entire sub-trees.
+ *
+ * The age of znodes is just the time-stamp when they were last looked at.
+ * The current shrinker first tries to evict old znodes, then young ones.
+ *
+ * Since the shrinker is global, it has to protect against races with FS
+ * un-mounts, which is done by the 'ubifs_infos_lock' and 'c->umount_mutex'.
+ */
+
+#include "ubifs.h"
+
+/* List of all UBIFS file-system instances */
+LIST_HEAD(ubifs_infos);
+
+/*
+ * We number each shrinker run and record the number on the ubifs_info structure
+ * so that we can easily work out which ubifs_info structures have already been
+ * done by the current run.
+ */
+static unsigned int shrinker_run_no;
+
+/* Protects 'ubifs_infos' list */
+DEFINE_SPINLOCK(ubifs_infos_lock);
+
+/* Global clean znode counter (for all mounted UBIFS instances) */
+atomic_long_t ubifs_clean_zn_cnt;
+
+/**
+ * shrink_tnc - shrink TNC tree.
+ * @c: UBIFS file-system description object
+ * @nr: number of znodes to free
+ * @age: the age of znodes to free
+ * @contention: if any contention, this is set to %1
+ *
+ * This function traverses TNC tree and frees clean znodes. It does not free
+ * clean znodes which younger then @age. Returns number of freed znodes.
+ */
+static int shrink_tnc(struct ubifs_info *c, int nr, int age, int *contention)
+{
+	int total_freed = 0;
+	struct ubifs_znode *znode, *zprev;
+	int time = get_seconds();
+
+	ubifs_assert(mutex_is_locked(&c->umount_mutex));
+	ubifs_assert(mutex_is_locked(&c->tnc_mutex));
+
+	if (!c->zroot.znode || atomic_long_read(&c->clean_zn_cnt) == 0)
+		return 0;
+
+	/*
+	 * Traverse the TNC tree in levelorder manner, so that it is possible
+	 * to destroy large sub-trees. Indeed, if a znode is old, then all its
+	 * children are older or of the same age.
+	 *
+	 * Note, we are holding 'c->tnc_mutex', so we do not have to lock the
+	 * 'c->space_lock' when _reading_ 'c->clean_zn_cnt', because it is
+	 * changed only when the 'c->tnc_mutex' is held.
+	 */
+	zprev = NULL;
+	znode = ubifs_tnc_levelorder_next(c->zroot.znode, NULL);
+	while (znode && total_freed < nr &&
+	       atomic_long_read(&c->clean_zn_cnt) > 0) {
+		int freed;
+
+		/*
+		 * If the znode is clean, but it is in the 'c->cnext' list, this
+		 * means that this znode has just been written to flash as a
+		 * part of commit and was marked clean. They will be removed
+		 * from the list at end commit. We cannot change the list,
+		 * because it is not protected by any mutex (design decision to
+		 * make commit really independent and parallel to main I/O). So
+		 * we just skip these znodes.
+		 *
+		 * Note, the 'clean_zn_cnt' counters are not updated until
+		 * after the commit, so the UBIFS shrinker does not report
+		 * the znodes which are in the 'c->cnext' list as freeable.
+		 *
+		 * Also note, if the root of a sub-tree is not in 'c->cnext',
+		 * then the whole sub-tree is not in 'c->cnext' as well, so it
+		 * is safe to dump whole sub-tree.
+		 */
+
+		if (znode->cnext) {
+			/*
+			 * Very soon these znodes will be removed from the list
+			 * and become freeable.
+			 */
+			*contention = 1;
+		} else if (!ubifs_zn_dirty(znode) &&
+			   abs(time - znode->time) >= age) {
+			if (znode->parent)
+				znode->parent->zbranch[znode->iip].znode = NULL;
+			else
+				c->zroot.znode = NULL;
+
+			freed = ubifs_destroy_tnc_subtree(znode);
+			atomic_long_sub(freed, &ubifs_clean_zn_cnt);
+			atomic_long_sub(freed, &c->clean_zn_cnt);
+			ubifs_assert(atomic_long_read(&c->clean_zn_cnt) >= 0);
+			total_freed += freed;
+			znode = zprev;
+		}
+
+		if (unlikely(!c->zroot.znode))
+			break;
+
+		zprev = znode;
+		znode = ubifs_tnc_levelorder_next(c->zroot.znode, znode);
+		cond_resched();
+	}
+
+	return total_freed;
+}
+
+/**
+ * shrink_tnc_trees - shrink UBIFS TNC trees.
+ * @nr: number of znodes to free
+ * @age: the age of znodes to free
+ * @contention: if any contention, this is set to %1
+ *
+ * This function walks the list of mounted UBIFS file-systems and frees clean
+ * znodes which are older then @age, until at least @nr znodes are freed.
+ * Returns the number of freed znodes.
+ */
+static int shrink_tnc_trees(int nr, int age, int *contention)
+{
+	struct ubifs_info *c;
+	struct list_head *p;
+	unsigned int run_no;
+	int freed = 0;
+
+	spin_lock(&ubifs_infos_lock);
+	do {
+		run_no = ++shrinker_run_no;
+	} while (run_no == 0);
+	/* Iterate over all mounted UBIFS file-systems and try to shrink them */
+	p = ubifs_infos.next;
+	while (p != &ubifs_infos) {
+		c = list_entry(p, struct ubifs_info, infos_list);
+		/*
+		 * We move the ones we do to the end of the list, so we stop
+		 * when we see one we have already done.
+		 */
+		if (c->shrinker_run_no == run_no)
+			break;
+		if (!mutex_trylock(&c->umount_mutex)) {
+			/* Some un-mount is in progress, try next FS */
+			*contention = 1;
+			p = p->next;
+			continue;
+		}
+		/*
+		 * We're holding 'c->umount_mutex', so the file-system won't go
+		 * away.
+		 */
+		if (!mutex_trylock(&c->tnc_mutex)) {
+			mutex_unlock(&c->umount_mutex);
+			*contention = 1;
+			p = p->next;
+			continue;
+		}
+		spin_unlock(&ubifs_infos_lock);
+		/*
+		 * OK, now we have TNC locked, the file-system cannot go away -
+		 * it is safe to reap the cache.
+		 */
+		c->shrinker_run_no = run_no;
+		freed += shrink_tnc(c, nr, age, contention);
+		mutex_unlock(&c->tnc_mutex);
+		spin_lock(&ubifs_infos_lock);
+		/* Get the next list element before we move this one */
+		p = p->next;
+		/*
+		 * Move this one to the end of the list to provide some
+		 * fairness.
+		 */
+		list_del(&c->infos_list);
+		list_add_tail(&c->infos_list, &ubifs_infos);
+		mutex_unlock(&c->umount_mutex);
+		if (freed >= nr)
+			break;
+	}
+	spin_unlock(&ubifs_infos_lock);
+	return freed;
+}
+
+/**
+ * kick_a_thread - kick a background thread to start commit.
+ *
+ * This function kicks a background thread to start background commit. Returns
+ * %-1 if a thread was kicked or there is another reason to assume the memory
+ * will soon be freed or become freeable. If there are no dirty znodes, returns
+ * %0.
+ */
+static int kick_a_thread(void)
+{
+	int i;
+	struct ubifs_info *c;
+
+	/*
+	 * Iterate over all mounted UBIFS file-systems and find out if there is
+	 * already an ongoing commit operation there. If no, then iterate for
+	 * the second time and initiate background commit.
+	 */
+	spin_lock(&ubifs_infos_lock);
+	for (i = 0; i < 2; i++) {
+		list_for_each_entry(c, &ubifs_infos, infos_list) {
+			long dirty_zn_cnt;
+
+			if (!mutex_trylock(&c->umount_mutex)) {
+				/*
+				 * Some un-mount is in progress, it will
+				 * certainly free memory, so just return.
+				 */
+				spin_unlock(&ubifs_infos_lock);
+				return -1;
+			}
+
+			dirty_zn_cnt = atomic_long_read(&c->dirty_zn_cnt);
+
+			if (!dirty_zn_cnt || c->cmt_state == COMMIT_BROKEN ||
+			    c->ro_media) {
+				mutex_unlock(&c->umount_mutex);
+				continue;
+			}
+
+			if (c->cmt_state != COMMIT_RESTING) {
+				spin_unlock(&ubifs_infos_lock);
+				mutex_unlock(&c->umount_mutex);
+				return -1;
+			}
+
+			if (i == 1) {
+				list_del(&c->infos_list);
+				list_add_tail(&c->infos_list, &ubifs_infos);
+				spin_unlock(&ubifs_infos_lock);
+
+				ubifs_request_bg_commit(c);
+				mutex_unlock(&c->umount_mutex);
+				return -1;
+			}
+			mutex_unlock(&c->umount_mutex);
+		}
+	}
+	spin_unlock(&ubifs_infos_lock);
+
+	return 0;
+}
+
+int ubifs_shrinker(int nr, gfp_t gfp_mask)
+{
+	int freed, contention = 0;
+	long clean_zn_cnt = atomic_long_read(&ubifs_clean_zn_cnt);
+
+	if (nr == 0)
+		return clean_zn_cnt;
+
+	if (!clean_zn_cnt) {
+		/*
+		 * No clean znodes, nothing to reap. All we can do in this case
+		 * is to kick background threads to start commit, which will
+		 * probably make clean znodes which, in turn, will be freeable.
+		 * And we return -1 which means will make VM call us again
+		 * later.
+		 */
+		dbg_tnc("no clean znodes, kick a thread");
+		return kick_a_thread();
+	}
+
+	freed = shrink_tnc_trees(nr, OLD_ZNODE_AGE, &contention);
+	if (freed >= nr)
+		goto out;
+
+	dbg_tnc("not enough old znodes, try to free young ones");
+	freed += shrink_tnc_trees(nr - freed, YOUNG_ZNODE_AGE, &contention);
+	if (freed >= nr)
+		goto out;
+
+	dbg_tnc("not enough young znodes, free all");
+	freed += shrink_tnc_trees(nr - freed, 0, &contention);
+
+	if (!freed && contention) {
+		dbg_tnc("freed nothing, but contention");
+		return -1;
+	}
+
+out:
+	dbg_tnc("%d znodes were freed, requested %d", freed, nr);
+	return freed;
+}
diff --git a/fs/ubifs/super.c b/fs/ubifs/super.c
new file mode 100644
index 00000000000..00eb9c68ad0
--- /dev/null
+++ b/fs/ubifs/super.c
@@ -0,0 +1,1951 @@
+/*
+ * This file is part of UBIFS.
+ *
+ * Copyright (C) 2006-2008 Nokia Corporation.
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 as published by
+ * the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
+ * more details.
+ *
+ * You should have received a copy of the GNU General Public License along with
+ * this program; if not, write to the Free Software Foundation, Inc., 51
+ * Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
+ *
+ * Authors: Artem Bityutskiy (Битюцкий Артём)
+ *          Adrian Hunter
+ */
+
+/*
+ * This file implements UBIFS initialization and VFS superblock operations. Some
+ * initialization stuff which is rather large and complex is placed at
+ * corresponding subsystems, but most of it is here.
+ */
+
+#include <linux/init.h>
+#include <linux/slab.h>
+#include <linux/module.h>
+#include <linux/ctype.h>
+#include <linux/random.h>
+#include <linux/kthread.h>
+#include <linux/parser.h>
+#include <linux/seq_file.h>
+#include <linux/mount.h>
+#include "ubifs.h"
+
+/* Slab cache for UBIFS inodes */
+struct kmem_cache *ubifs_inode_slab;
+
+/* UBIFS TNC shrinker description */
+static struct shrinker ubifs_shrinker_info = {
+	.shrink = ubifs_shrinker,
+	.seeks = DEFAULT_SEEKS,
+};
+
+/**
+ * validate_inode - validate inode.
+ * @c: UBIFS file-system description object
+ * @inode: the inode to validate
+ *
+ * This is a helper function for 'ubifs_iget()' which validates various fields
+ * of a newly built inode to make sure they contain sane values and prevent
+ * possible vulnerabilities. Returns zero if the inode is all right and
+ * a non-zero error code if not.
+ */
+static int validate_inode(struct ubifs_info *c, const struct inode *inode)
+{
+	int err;
+	const struct ubifs_inode *ui = ubifs_inode(inode);
+
+	if (inode->i_size > c->max_inode_sz) {
+		ubifs_err("inode is too large (%lld)",
+			  (long long)inode->i_size);
+		return 1;
+	}
+
+	if (ui->compr_type < 0 || ui->compr_type >= UBIFS_COMPR_TYPES_CNT) {
+		ubifs_err("unknown compression type %d", ui->compr_type);
+		return 2;
+	}
+
+	if (ui->xattr_names + ui->xattr_cnt > XATTR_LIST_MAX)
+		return 3;
+
+	if (ui->data_len < 0 || ui->data_len > UBIFS_MAX_INO_DATA)
+		return 4;
+
+	if (ui->xattr && (inode->i_mode & S_IFMT) != S_IFREG)
+		return 5;
+
+	if (!ubifs_compr_present(ui->compr_type)) {
+		ubifs_warn("inode %lu uses '%s' compression, but it was not "
+			   "compiled in", inode->i_ino,
+			   ubifs_compr_name(ui->compr_type));
+	}
+
+	err = dbg_check_dir_size(c, inode);
+	return err;
+}
+
+struct inode *ubifs_iget(struct super_block *sb, unsigned long inum)
+{
+	int err;
+	union ubifs_key key;
+	struct ubifs_ino_node *ino;
+	struct ubifs_info *c = sb->s_fs_info;
+	struct inode *inode;
+	struct ubifs_inode *ui;
+
+	dbg_gen("inode %lu", inum);
+
+	inode = iget_locked(sb, inum);
+	if (!inode)
+		return ERR_PTR(-ENOMEM);
+	if (!(inode->i_state & I_NEW))
+		return inode;
+	ui = ubifs_inode(inode);
+
+	ino = kmalloc(UBIFS_MAX_INO_NODE_SZ, GFP_NOFS);
+	if (!ino) {
+		err = -ENOMEM;
+		goto out;
+	}
+
+	ino_key_init(c, &key, inode->i_ino);
+
+	err = ubifs_tnc_lookup(c, &key, ino);
+	if (err)
+		goto out_ino;
+
+	inode->i_flags |= (S_NOCMTIME | S_NOATIME);
+	inode->i_nlink = le32_to_cpu(ino->nlink);
+	inode->i_uid   = le32_to_cpu(ino->uid);
+	inode->i_gid   = le32_to_cpu(ino->gid);
+	inode->i_atime.tv_sec  = (int64_t)le64_to_cpu(ino->atime_sec);
+	inode->i_atime.tv_nsec = le32_to_cpu(ino->atime_nsec);
+	inode->i_mtime.tv_sec  = (int64_t)le64_to_cpu(ino->mtime_sec);
+	inode->i_mtime.tv_nsec = le32_to_cpu(ino->mtime_nsec);
+	inode->i_ctime.tv_sec  = (int64_t)le64_to_cpu(ino->ctime_sec);
+	inode->i_ctime.tv_nsec = le32_to_cpu(ino->ctime_nsec);
+	inode->i_mode = le32_to_cpu(ino->mode);
+	inode->i_size = le64_to_cpu(ino->size);
+
+	ui->data_len    = le32_to_cpu(ino->data_len);
+	ui->flags       = le32_to_cpu(ino->flags);
+	ui->compr_type  = le16_to_cpu(ino->compr_type);
+	ui->creat_sqnum = le64_to_cpu(ino->creat_sqnum);
+	ui->xattr_cnt   = le32_to_cpu(ino->xattr_cnt);
+	ui->xattr_size  = le32_to_cpu(ino->xattr_size);
+	ui->xattr_names = le32_to_cpu(ino->xattr_names);
+	ui->synced_i_size = ui->ui_size = inode->i_size;
+
+	ui->xattr = (ui->flags & UBIFS_XATTR_FL) ? 1 : 0;
+
+	err = validate_inode(c, inode);
+	if (err)
+		goto out_invalid;
+
+	/* Disable readahead */
+	inode->i_mapping->backing_dev_info = &c->bdi;
+
+	switch (inode->i_mode & S_IFMT) {
+	case S_IFREG:
+		inode->i_mapping->a_ops = &ubifs_file_address_operations;
+		inode->i_op = &ubifs_file_inode_operations;
+		inode->i_fop = &ubifs_file_operations;
+		if (ui->xattr) {
+			ui->data = kmalloc(ui->data_len + 1, GFP_NOFS);
+			if (!ui->data) {
+				err = -ENOMEM;
+				goto out_ino;
+			}
+			memcpy(ui->data, ino->data, ui->data_len);
+			((char *)ui->data)[ui->data_len] = '\0';
+		} else if (ui->data_len != 0) {
+			err = 10;
+			goto out_invalid;
+		}
+		break;
+	case S_IFDIR:
+		inode->i_op  = &ubifs_dir_inode_operations;
+		inode->i_fop = &ubifs_dir_operations;
+		if (ui->data_len != 0) {
+			err = 11;
+			goto out_invalid;
+		}
+		break;
+	case S_IFLNK:
+		inode->i_op = &ubifs_symlink_inode_operations;
+		if (ui->data_len <= 0 || ui->data_len > UBIFS_MAX_INO_DATA) {
+			err = 12;
+			goto out_invalid;
+		}
+		ui->data = kmalloc(ui->data_len + 1, GFP_NOFS);
+		if (!ui->data) {
+			err = -ENOMEM;
+			goto out_ino;
+		}
+		memcpy(ui->data, ino->data, ui->data_len);
+		((char *)ui->data)[ui->data_len] = '\0';
+		break;
+	case S_IFBLK:
+	case S_IFCHR:
+	{
+		dev_t rdev;
+		union ubifs_dev_desc *dev;
+
+		ui->data = kmalloc(sizeof(union ubifs_dev_desc), GFP_NOFS);
+		if (!ui->data) {
+			err = -ENOMEM;
+			goto out_ino;
+		}
+
+		dev = (union ubifs_dev_desc *)ino->data;
+		if (ui->data_len == sizeof(dev->new))
+			rdev = new_decode_dev(le32_to_cpu(dev->new));
+		else if (ui->data_len == sizeof(dev->huge))
+			rdev = huge_decode_dev(le64_to_cpu(dev->huge));
+		else {
+			err = 13;
+			goto out_invalid;
+		}
+		memcpy(ui->data, ino->data, ui->data_len);
+		inode->i_op = &ubifs_file_inode_operations;
+		init_special_inode(inode, inode->i_mode, rdev);
+		break;
+	}
+	case S_IFSOCK:
+	case S_IFIFO:
+		inode->i_op = &ubifs_file_inode_operations;
+		init_special_inode(inode, inode->i_mode, 0);
+		if (ui->data_len != 0) {
+			err = 14;
+			goto out_invalid;
+		}
+		break;
+	default:
+		err = 15;
+		goto out_invalid;
+	}
+
+	kfree(ino);
+	ubifs_set_inode_flags(inode);
+	unlock_new_inode(inode);
+	return inode;
+
+out_invalid:
+	ubifs_err("inode %lu validation failed, error %d", inode->i_ino, err);
+	dbg_dump_node(c, ino);
+	dbg_dump_inode(c, inode);
+	err = -EINVAL;
+out_ino:
+	kfree(ino);
+out:
+	ubifs_err("failed to read inode %lu, error %d", inode->i_ino, err);
+	iget_failed(inode);
+	return ERR_PTR(err);
+}
+
+static struct inode *ubifs_alloc_inode(struct super_block *sb)
+{
+	struct ubifs_inode *ui;
+
+	ui = kmem_cache_alloc(ubifs_inode_slab, GFP_NOFS);
+	if (!ui)
+		return NULL;
+
+	memset((void *)ui + sizeof(struct inode), 0,
+	       sizeof(struct ubifs_inode) - sizeof(struct inode));
+	mutex_init(&ui->ui_mutex);
+	spin_lock_init(&ui->ui_lock);
+	return &ui->vfs_inode;
+};
+
+static void ubifs_destroy_inode(struct inode *inode)
+{
+	struct ubifs_inode *ui = ubifs_inode(inode);
+
+	kfree(ui->data);
+	kmem_cache_free(ubifs_inode_slab, inode);
+}
+
+/*
+ * Note, Linux write-back code calls this without 'i_mutex'.
+ */
+static int ubifs_write_inode(struct inode *inode, int wait)
+{
+	int err;
+	struct ubifs_info *c = inode->i_sb->s_fs_info;
+	struct ubifs_inode *ui = ubifs_inode(inode);
+
+	ubifs_assert(!ui->xattr);
+	if (is_bad_inode(inode))
+		return 0;
+
+	mutex_lock(&ui->ui_mutex);
+	/*
+	 * Due to races between write-back forced by budgeting
+	 * (see 'sync_some_inodes()') and pdflush write-back, the inode may
+	 * have already been synchronized, do not do this again. This might
+	 * also happen if it was synchronized in an VFS operation, e.g.
+	 * 'ubifs_link()'.
+	 */
+	if (!ui->dirty) {
+		mutex_unlock(&ui->ui_mutex);
+		return 0;
+	}
+
+	dbg_gen("inode %lu", inode->i_ino);
+	err = ubifs_jnl_write_inode(c, inode, 0);
+	if (err)
+		ubifs_err("can't write inode %lu, error %d", inode->i_ino, err);
+
+	ui->dirty = 0;
+	mutex_unlock(&ui->ui_mutex);
+	ubifs_release_dirty_inode_budget(c, ui);
+	return err;
+}
+
+static void ubifs_delete_inode(struct inode *inode)
+{
+	int err;
+	struct ubifs_info *c = inode->i_sb->s_fs_info;
+
+	if (ubifs_inode(inode)->xattr)
+		/*
+		 * Extended attribute inode deletions are fully handled in
+		 * 'ubifs_removexattr()'. These inodes are special and have
+		 * limited usage, so there is nothing to do here.
+		 */
+		goto out;
+
+	dbg_gen("inode %lu", inode->i_ino);
+	ubifs_assert(!atomic_read(&inode->i_count));
+	ubifs_assert(inode->i_nlink == 0);
+
+	truncate_inode_pages(&inode->i_data, 0);
+	if (is_bad_inode(inode))
+		goto out;
+
+	ubifs_inode(inode)->ui_size = inode->i_size = 0;
+	err = ubifs_jnl_write_inode(c, inode, 1);
+	if (err)
+		/*
+		 * Worst case we have a lost orphan inode wasting space, so a
+		 * simple error message is ok here.
+		 */
+		ubifs_err("can't write inode %lu, error %d", inode->i_ino, err);
+out:
+	clear_inode(inode);
+}
+
+static void ubifs_dirty_inode(struct inode *inode)
+{
+	struct ubifs_inode *ui = ubifs_inode(inode);
+
+	ubifs_assert(mutex_is_locked(&ui->ui_mutex));
+	if (!ui->dirty) {
+		ui->dirty = 1;
+		dbg_gen("inode %lu",  inode->i_ino);
+	}
+}
+
+static int ubifs_statfs(struct dentry *dentry, struct kstatfs *buf)
+{
+	struct ubifs_info *c = dentry->d_sb->s_fs_info;
+	unsigned long long free;
+
+	free = ubifs_budg_get_free_space(c);
+	dbg_gen("free space %lld bytes (%lld blocks)",
+		free, free >> UBIFS_BLOCK_SHIFT);
+
+	buf->f_type = UBIFS_SUPER_MAGIC;
+	buf->f_bsize = UBIFS_BLOCK_SIZE;
+	buf->f_blocks = c->block_cnt;
+	buf->f_bfree = free >> UBIFS_BLOCK_SHIFT;
+	if (free > c->report_rp_size)
+		buf->f_bavail = (free - c->report_rp_size) >> UBIFS_BLOCK_SHIFT;
+	else
+		buf->f_bavail = 0;
+	buf->f_files = 0;
+	buf->f_ffree = 0;
+	buf->f_namelen = UBIFS_MAX_NLEN;
+
+	return 0;
+}
+
+static int ubifs_show_options(struct seq_file *s, struct vfsmount *mnt)
+{
+	struct ubifs_info *c = mnt->mnt_sb->s_fs_info;
+
+	if (c->mount_opts.unmount_mode == 2)
+		seq_printf(s, ",fast_unmount");
+	else if (c->mount_opts.unmount_mode == 1)
+		seq_printf(s, ",norm_unmount");
+
+	return 0;
+}
+
+static int ubifs_sync_fs(struct super_block *sb, int wait)
+{
+	struct ubifs_info *c = sb->s_fs_info;
+	int i, ret = 0, err;
+
+	if (c->jheads)
+		for (i = 0; i < c->jhead_cnt; i++) {
+			err = ubifs_wbuf_sync(&c->jheads[i].wbuf);
+			if (err && !ret)
+				ret = err;
+		}
+	/*
+	 * We ought to call sync for c->ubi but it does not have one. If it had
+	 * it would in turn call mtd->sync, however mtd operations are
+	 * synchronous anyway, so we don't lose any sleep here.
+	 */
+	return ret;
+}
+
+/**
+ * init_constants_early - initialize UBIFS constants.
+ * @c: UBIFS file-system description object
+ *
+ * This function initialize UBIFS constants which do not need the superblock to
+ * be read. It also checks that the UBI volume satisfies basic UBIFS
+ * requirements. Returns zero in case of success and a negative error code in
+ * case of failure.
+ */
+static int init_constants_early(struct ubifs_info *c)
+{
+	if (c->vi.corrupted) {
+		ubifs_warn("UBI volume is corrupted - read-only mode");
+		c->ro_media = 1;
+	}
+
+	if (c->di.ro_mode) {
+		ubifs_msg("read-only UBI device");
+		c->ro_media = 1;
+	}
+
+	if (c->vi.vol_type == UBI_STATIC_VOLUME) {
+		ubifs_msg("static UBI volume - read-only mode");
+		c->ro_media = 1;
+	}
+
+	c->leb_cnt = c->vi.size;
+	c->leb_size = c->vi.usable_leb_size;
+	c->half_leb_size = c->leb_size / 2;
+	c->min_io_size = c->di.min_io_size;
+	c->min_io_shift = fls(c->min_io_size) - 1;
+
+	if (c->leb_size < UBIFS_MIN_LEB_SZ) {
+		ubifs_err("too small LEBs (%d bytes), min. is %d bytes",
+			  c->leb_size, UBIFS_MIN_LEB_SZ);
+		return -EINVAL;
+	}
+
+	if (c->leb_cnt < UBIFS_MIN_LEB_CNT) {
+		ubifs_err("too few LEBs (%d), min. is %d",
+			  c->leb_cnt, UBIFS_MIN_LEB_CNT);
+		return -EINVAL;
+	}
+
+	if (!is_power_of_2(c->min_io_size)) {
+		ubifs_err("bad min. I/O size %d", c->min_io_size);
+		return -EINVAL;
+	}
+
+	/*
+	 * UBIFS aligns all node to 8-byte boundary, so to make function in
+	 * io.c simpler, assume minimum I/O unit size to be 8 bytes if it is
+	 * less than 8.
+	 */
+	if (c->min_io_size < 8) {
+		c->min_io_size = 8;
+		c->min_io_shift = 3;
+	}
+
+	c->ref_node_alsz = ALIGN(UBIFS_REF_NODE_SZ, c->min_io_size);
+	c->mst_node_alsz = ALIGN(UBIFS_MST_NODE_SZ, c->min_io_size);
+
+	/*
+	 * Initialize node length ranges which are mostly needed for node
+	 * length validation.
+	 */
+	c->ranges[UBIFS_PAD_NODE].len  = UBIFS_PAD_NODE_SZ;
+	c->ranges[UBIFS_SB_NODE].len   = UBIFS_SB_NODE_SZ;
+	c->ranges[UBIFS_MST_NODE].len  = UBIFS_MST_NODE_SZ;
+	c->ranges[UBIFS_REF_NODE].len  = UBIFS_REF_NODE_SZ;
+	c->ranges[UBIFS_TRUN_NODE].len = UBIFS_TRUN_NODE_SZ;
+	c->ranges[UBIFS_CS_NODE].len   = UBIFS_CS_NODE_SZ;
+
+	c->ranges[UBIFS_INO_NODE].min_len  = UBIFS_INO_NODE_SZ;
+	c->ranges[UBIFS_INO_NODE].max_len  = UBIFS_MAX_INO_NODE_SZ;
+	c->ranges[UBIFS_ORPH_NODE].min_len =
+				UBIFS_ORPH_NODE_SZ + sizeof(__le64);
+	c->ranges[UBIFS_ORPH_NODE].max_len = c->leb_size;
+	c->ranges[UBIFS_DENT_NODE].min_len = UBIFS_DENT_NODE_SZ;
+	c->ranges[UBIFS_DENT_NODE].max_len = UBIFS_MAX_DENT_NODE_SZ;
+	c->ranges[UBIFS_XENT_NODE].min_len = UBIFS_XENT_NODE_SZ;
+	c->ranges[UBIFS_XENT_NODE].max_len = UBIFS_MAX_XENT_NODE_SZ;
+	c->ranges[UBIFS_DATA_NODE].min_len = UBIFS_DATA_NODE_SZ;
+	c->ranges[UBIFS_DATA_NODE].max_len = UBIFS_MAX_DATA_NODE_SZ;
+	/*
+	 * Minimum indexing node size is amended later when superblock is
+	 * read and the key length is known.
+	 */
+	c->ranges[UBIFS_IDX_NODE].min_len = UBIFS_IDX_NODE_SZ + UBIFS_BRANCH_SZ;
+	/*
+	 * Maximum indexing node size is amended later when superblock is
+	 * read and the fanout is known.
+	 */
+	c->ranges[UBIFS_IDX_NODE].max_len = INT_MAX;
+
+	/*
+	 * Initialize dead and dark LEB space watermarks.
+	 *
+	 * Dead space is the space which cannot be used. Its watermark is
+	 * equivalent to min. I/O unit or minimum node size if it is greater
+	 * then min. I/O unit.
+	 *
+	 * Dark space is the space which might be used, or might not, depending
+	 * on which node should be written to the LEB. Its watermark is
+	 * equivalent to maximum UBIFS node size.
+	 */
+	c->dead_wm = ALIGN(MIN_WRITE_SZ, c->min_io_size);
+	c->dark_wm = ALIGN(UBIFS_MAX_NODE_SZ, c->min_io_size);
+
+	return 0;
+}
+
+/**
+ * bud_wbuf_callback - bud LEB write-buffer synchronization call-back.
+ * @c: UBIFS file-system description object
+ * @lnum: LEB the write-buffer was synchronized to
+ * @free: how many free bytes left in this LEB
+ * @pad: how many bytes were padded
+ *
+ * This is a callback function which is called by the I/O unit when the
+ * write-buffer is synchronized. We need this to correctly maintain space
+ * accounting in bud logical eraseblocks. This function returns zero in case of
+ * success and a negative error code in case of failure.
+ *
+ * This function actually belongs to the journal, but we keep it here because
+ * we want to keep it static.
+ */
+static int bud_wbuf_callback(struct ubifs_info *c, int lnum, int free, int pad)
+{
+	return ubifs_update_one_lp(c, lnum, free, pad, 0, 0);
+}
+
+/*
+ * init_constants_late - initialize UBIFS constants.
+ * @c: UBIFS file-system description object
+ *
+ * This is a helper function which initializes various UBIFS constants after
+ * the superblock has been read. It also checks various UBIFS parameters and
+ * makes sure they are all right. Returns zero in case of success and a
+ * negative error code in case of failure.
+ */
+static int init_constants_late(struct ubifs_info *c)
+{
+	int tmp, err;
+	uint64_t tmp64;
+
+	c->main_bytes = (long long)c->main_lebs * c->leb_size;
+	c->max_znode_sz = sizeof(struct ubifs_znode) +
+				c->fanout * sizeof(struct ubifs_zbranch);
+
+	tmp = ubifs_idx_node_sz(c, 1);
+	c->ranges[UBIFS_IDX_NODE].min_len = tmp;
+	c->min_idx_node_sz = ALIGN(tmp, 8);
+
+	tmp = ubifs_idx_node_sz(c, c->fanout);
+	c->ranges[UBIFS_IDX_NODE].max_len = tmp;
+	c->max_idx_node_sz = ALIGN(tmp, 8);
+
+	/* Make sure LEB size is large enough to fit full commit */
+	tmp = UBIFS_CS_NODE_SZ + UBIFS_REF_NODE_SZ * c->jhead_cnt;
+	tmp = ALIGN(tmp, c->min_io_size);
+	if (tmp > c->leb_size) {
+		dbg_err("too small LEB size %d, at least %d needed",
+			c->leb_size, tmp);
+		return -EINVAL;
+	}
+
+	/*
+	 * Make sure that the log is large enough to fit reference nodes for
+	 * all buds plus one reserved LEB.
+	 */
+	tmp64 = c->max_bud_bytes;
+	tmp = do_div(tmp64, c->leb_size);
+	c->max_bud_cnt = tmp64 + !!tmp;
+	tmp = (c->ref_node_alsz * c->max_bud_cnt + c->leb_size - 1);
+	tmp /= c->leb_size;
+	tmp += 1;
+	if (c->log_lebs < tmp) {
+		dbg_err("too small log %d LEBs, required min. %d LEBs",
+			c->log_lebs, tmp);
+		return -EINVAL;
+	}
+
+	/*
+	 * When budgeting we assume worst-case scenarios when the pages are not
+	 * be compressed and direntries are of the maximum size.
+	 *
+	 * Note, data, which may be stored in inodes is budgeted separately, so
+	 * it is not included into 'c->inode_budget'.
+	 */
+	c->page_budget = UBIFS_MAX_DATA_NODE_SZ * UBIFS_BLOCKS_PER_PAGE;
+	c->inode_budget = UBIFS_INO_NODE_SZ;
+	c->dent_budget = UBIFS_MAX_DENT_NODE_SZ;
+
+	/*
+	 * When the amount of flash space used by buds becomes
+	 * 'c->max_bud_bytes', UBIFS just blocks all writers and starts commit.
+	 * The writers are unblocked when the commit is finished. To avoid
+	 * writers to be blocked UBIFS initiates background commit in advance,
+	 * when number of bud bytes becomes above the limit defined below.
+	 */
+	c->bg_bud_bytes = (c->max_bud_bytes * 13) >> 4;
+
+	/*
+	 * Ensure minimum journal size. All the bytes in the journal heads are
+	 * considered to be used, when calculating the current journal usage.
+	 * Consequently, if the journal is too small, UBIFS will treat it as
+	 * always full.
+	 */
+	tmp64 = (uint64_t)(c->jhead_cnt + 1) * c->leb_size + 1;
+	if (c->bg_bud_bytes < tmp64)
+		c->bg_bud_bytes = tmp64;
+	if (c->max_bud_bytes < tmp64 + c->leb_size)
+		c->max_bud_bytes = tmp64 + c->leb_size;
+
+	err = ubifs_calc_lpt_geom(c);
+	if (err)
+		return err;
+
+	c->min_idx_lebs = ubifs_calc_min_idx_lebs(c);
+
+	/*
+	 * Calculate total amount of FS blocks. This number is not used
+	 * internally because it does not make much sense for UBIFS, but it is
+	 * necessary to report something for the 'statfs()' call.
+	 *
+	 * Subtract the LEB reserved for GC and the LEB which is reserved for
+	 * deletions.
+	 *
+	 * Review 'ubifs_calc_available()' if changing this calculation.
+	 */
+	tmp64 = c->main_lebs - 2;
+	tmp64 *= (uint64_t)c->leb_size - c->dark_wm;
+	tmp64 = ubifs_reported_space(c, tmp64);
+	c->block_cnt = tmp64 >> UBIFS_BLOCK_SHIFT;
+
+	return 0;
+}
+
+/**
+ * take_gc_lnum - reserve GC LEB.
+ * @c: UBIFS file-system description object
+ *
+ * This function ensures that the LEB reserved for garbage collection is
+ * unmapped and is marked as "taken" in lprops. We also have to set free space
+ * to LEB size and dirty space to zero, because lprops may contain out-of-date
+ * information if the file-system was un-mounted before it has been committed.
+ * This function returns zero in case of success and a negative error code in
+ * case of failure.
+ */
+static int take_gc_lnum(struct ubifs_info *c)
+{
+	int err;
+
+	if (c->gc_lnum == -1) {
+		ubifs_err("no LEB for GC");
+		return -EINVAL;
+	}
+
+	err = ubifs_leb_unmap(c, c->gc_lnum);
+	if (err)
+		return err;
+
+	/* And we have to tell lprops that this LEB is taken */
+	err = ubifs_change_one_lp(c, c->gc_lnum, c->leb_size, 0,
+				  LPROPS_TAKEN, 0, 0);
+	return err;
+}
+
+/**
+ * alloc_wbufs - allocate write-buffers.
+ * @c: UBIFS file-system description object
+ *
+ * This helper function allocates and initializes UBIFS write-buffers. Returns
+ * zero in case of success and %-ENOMEM in case of failure.
+ */
+static int alloc_wbufs(struct ubifs_info *c)
+{
+	int i, err;
+
+	c->jheads = kzalloc(c->jhead_cnt * sizeof(struct ubifs_jhead),
+			   GFP_KERNEL);
+	if (!c->jheads)
+		return -ENOMEM;
+
+	/* Initialize journal heads */
+	for (i = 0; i < c->jhead_cnt; i++) {
+		INIT_LIST_HEAD(&c->jheads[i].buds_list);
+		err = ubifs_wbuf_init(c, &c->jheads[i].wbuf);
+		if (err)
+			return err;
+
+		c->jheads[i].wbuf.sync_callback = &bud_wbuf_callback;
+		c->jheads[i].wbuf.jhead = i;
+	}
+
+	c->jheads[BASEHD].wbuf.dtype = UBI_SHORTTERM;
+	/*
+	 * Garbage Collector head likely contains long-term data and
+	 * does not need to be synchronized by timer.
+	 */
+	c->jheads[GCHD].wbuf.dtype = UBI_LONGTERM;
+	c->jheads[GCHD].wbuf.timeout = 0;
+
+	return 0;
+}
+
+/**
+ * free_wbufs - free write-buffers.
+ * @c: UBIFS file-system description object
+ */
+static void free_wbufs(struct ubifs_info *c)
+{
+	int i;
+
+	if (c->jheads) {
+		for (i = 0; i < c->jhead_cnt; i++) {
+			kfree(c->jheads[i].wbuf.buf);
+			kfree(c->jheads[i].wbuf.inodes);
+		}
+		kfree(c->jheads);
+		c->jheads = NULL;
+	}
+}
+
+/**
+ * free_orphans - free orphans.
+ * @c: UBIFS file-system description object
+ */
+static void free_orphans(struct ubifs_info *c)
+{
+	struct ubifs_orphan *orph;
+
+	while (c->orph_dnext) {
+		orph = c->orph_dnext;
+		c->orph_dnext = orph->dnext;
+		list_del(&orph->list);
+		kfree(orph);
+	}
+
+	while (!list_empty(&c->orph_list)) {
+		orph = list_entry(c->orph_list.next, struct ubifs_orphan, list);
+		list_del(&orph->list);
+		kfree(orph);
+		dbg_err("orphan list not empty at unmount");
+	}
+
+	vfree(c->orph_buf);
+	c->orph_buf = NULL;
+}
+
+/**
+ * free_buds - free per-bud objects.
+ * @c: UBIFS file-system description object
+ */
+static void free_buds(struct ubifs_info *c)
+{
+	struct rb_node *this = c->buds.rb_node;
+	struct ubifs_bud *bud;
+
+	while (this) {
+		if (this->rb_left)
+			this = this->rb_left;
+		else if (this->rb_right)
+			this = this->rb_right;
+		else {
+			bud = rb_entry(this, struct ubifs_bud, rb);
+			this = rb_parent(this);
+			if (this) {
+				if (this->rb_left == &bud->rb)
+					this->rb_left = NULL;
+				else
+					this->rb_right = NULL;
+			}
+			kfree(bud);
+		}
+	}
+}
+
+/**
+ * check_volume_empty - check if the UBI volume is empty.
+ * @c: UBIFS file-system description object
+ *
+ * This function checks if the UBIFS volume is empty by looking if its LEBs are
+ * mapped or not. The result of checking is stored in the @c->empty variable.
+ * Returns zero in case of success and a negative error code in case of
+ * failure.
+ */
+static int check_volume_empty(struct ubifs_info *c)
+{
+	int lnum, err;
+
+	c->empty = 1;
+	for (lnum = 0; lnum < c->leb_cnt; lnum++) {
+		err = ubi_is_mapped(c->ubi, lnum);
+		if (unlikely(err < 0))
+			return err;
+		if (err == 1) {
+			c->empty = 0;
+			break;
+		}
+
+		cond_resched();
+	}
+
+	return 0;
+}
+
+/*
+ * UBIFS mount options.
+ *
+ * Opt_fast_unmount: do not run a journal commit before un-mounting
+ * Opt_norm_unmount: run a journal commit before un-mounting
+ * Opt_err: just end of array marker
+ */
+enum {
+	Opt_fast_unmount,
+	Opt_norm_unmount,
+	Opt_err,
+};
+
+static match_table_t tokens = {
+	{Opt_fast_unmount, "fast_unmount"},
+	{Opt_norm_unmount, "norm_unmount"},
+	{Opt_err, NULL},
+};
+
+/**
+ * ubifs_parse_options - parse mount parameters.
+ * @c: UBIFS file-system description object
+ * @options: parameters to parse
+ * @is_remount: non-zero if this is FS re-mount
+ *
+ * This function parses UBIFS mount options and returns zero in case success
+ * and a negative error code in case of failure.
+ */
+static int ubifs_parse_options(struct ubifs_info *c, char *options,
+			       int is_remount)
+{
+	char *p;
+	substring_t args[MAX_OPT_ARGS];
+
+	if (!options)
+		return 0;
+
+	while ((p = strsep(&options, ","))) {
+		int token;
+
+		if (!*p)
+			continue;
+
+		token = match_token(p, tokens, args);
+		switch (token) {
+		case Opt_fast_unmount:
+			c->mount_opts.unmount_mode = 2;
+			c->fast_unmount = 1;
+			break;
+		case Opt_norm_unmount:
+			c->mount_opts.unmount_mode = 1;
+			c->fast_unmount = 0;
+			break;
+		default:
+			ubifs_err("unrecognized mount option \"%s\" "
+				  "or missing value", p);
+			return -EINVAL;
+		}
+	}
+
+	return 0;
+}
+
+/**
+ * destroy_journal - destroy journal data structures.
+ * @c: UBIFS file-system description object
+ *
+ * This function destroys journal data structures including those that may have
+ * been created by recovery functions.
+ */
+static void destroy_journal(struct ubifs_info *c)
+{
+	while (!list_empty(&c->unclean_leb_list)) {
+		struct ubifs_unclean_leb *ucleb;
+
+		ucleb = list_entry(c->unclean_leb_list.next,
+				   struct ubifs_unclean_leb, list);
+		list_del(&ucleb->list);
+		kfree(ucleb);
+	}
+	while (!list_empty(&c->old_buds)) {
+		struct ubifs_bud *bud;
+
+		bud = list_entry(c->old_buds.next, struct ubifs_bud, list);
+		list_del(&bud->list);
+		kfree(bud);
+	}
+	ubifs_destroy_idx_gc(c);
+	ubifs_destroy_size_tree(c);
+	ubifs_tnc_close(c);
+	free_buds(c);
+}
+
+/**
+ * mount_ubifs - mount UBIFS file-system.
+ * @c: UBIFS file-system description object
+ *
+ * This function mounts UBIFS file system. Returns zero in case of success and
+ * a negative error code in case of failure.
+ *
+ * Note, the function does not de-allocate resources it it fails half way
+ * through, and the caller has to do this instead.
+ */
+static int mount_ubifs(struct ubifs_info *c)
+{
+	struct super_block *sb = c->vfs_sb;
+	int err, mounted_read_only = (sb->s_flags & MS_RDONLY);
+	long long x;
+	size_t sz;
+
+	err = init_constants_early(c);
+	if (err)
+		return err;
+
+#ifdef CONFIG_UBIFS_FS_DEBUG
+	c->dbg_buf = vmalloc(c->leb_size);
+	if (!c->dbg_buf)
+		return -ENOMEM;
+#endif
+
+	err = check_volume_empty(c);
+	if (err)
+		goto out_free;
+
+	if (c->empty && (mounted_read_only || c->ro_media)) {
+		/*
+		 * This UBI volume is empty, and read-only, or the file system
+		 * is mounted read-only - we cannot format it.
+		 */
+		ubifs_err("can't format empty UBI volume: read-only %s",
+			  c->ro_media ? "UBI volume" : "mount");
+		err = -EROFS;
+		goto out_free;
+	}
+
+	if (c->ro_media && !mounted_read_only) {
+		ubifs_err("cannot mount read-write - read-only media");
+		err = -EROFS;
+		goto out_free;
+	}
+
+	/*
+	 * The requirement for the buffer is that it should fit indexing B-tree
+	 * height amount of integers. We assume the height if the TNC tree will
+	 * never exceed 64.
+	 */
+	err = -ENOMEM;
+	c->bottom_up_buf = kmalloc(BOTTOM_UP_HEIGHT * sizeof(int), GFP_KERNEL);
+	if (!c->bottom_up_buf)
+		goto out_free;
+
+	c->sbuf = vmalloc(c->leb_size);
+	if (!c->sbuf)
+		goto out_free;
+
+	if (!mounted_read_only) {
+		c->ileb_buf = vmalloc(c->leb_size);
+		if (!c->ileb_buf)
+			goto out_free;
+	}
+
+	err = ubifs_read_superblock(c);
+	if (err)
+		goto out_free;
+
+	/*
+	 * Make sure the compressor which is set as the default on in the
+	 * superblock was actually compiled in.
+	 */
+	if (!ubifs_compr_present(c->default_compr)) {
+		ubifs_warn("'%s' compressor is set by superblock, but not "
+			   "compiled in", ubifs_compr_name(c->default_compr));
+		c->default_compr = UBIFS_COMPR_NONE;
+	}
+
+	dbg_failure_mode_registration(c);
+
+	err = init_constants_late(c);
+	if (err)
+		goto out_dereg;
+
+	sz = ALIGN(c->max_idx_node_sz, c->min_io_size);
+	sz = ALIGN(sz + c->max_idx_node_sz, c->min_io_size);
+	c->cbuf = kmalloc(sz, GFP_NOFS);
+	if (!c->cbuf) {
+		err = -ENOMEM;
+		goto out_dereg;
+	}
+
+	if (!mounted_read_only) {
+		err = alloc_wbufs(c);
+		if (err)
+			goto out_cbuf;
+
+		/* Create background thread */
+		sprintf(c->bgt_name, BGT_NAME_PATTERN, c->vi.ubi_num,
+			c->vi.vol_id);
+		c->bgt = kthread_create(ubifs_bg_thread, c, c->bgt_name);
+		if (!c->bgt)
+			c->bgt = ERR_PTR(-EINVAL);
+		if (IS_ERR(c->bgt)) {
+			err = PTR_ERR(c->bgt);
+			c->bgt = NULL;
+			ubifs_err("cannot spawn \"%s\", error %d",
+				  c->bgt_name, err);
+			goto out_wbufs;
+		}
+		wake_up_process(c->bgt);
+	}
+
+	err = ubifs_read_master(c);
+	if (err)
+		goto out_master;
+
+	if ((c->mst_node->flags & cpu_to_le32(UBIFS_MST_DIRTY)) != 0) {
+		ubifs_msg("recovery needed");
+		c->need_recovery = 1;
+		if (!mounted_read_only) {
+			err = ubifs_recover_inl_heads(c, c->sbuf);
+			if (err)
+				goto out_master;
+		}
+	} else if (!mounted_read_only) {
+		/*
+		 * Set the "dirty" flag so that if we reboot uncleanly we
+		 * will notice this immediately on the next mount.
+		 */
+		c->mst_node->flags |= cpu_to_le32(UBIFS_MST_DIRTY);
+		err = ubifs_write_master(c);
+		if (err)
+			goto out_master;
+	}
+
+	err = ubifs_lpt_init(c, 1, !mounted_read_only);
+	if (err)
+		goto out_lpt;
+
+	err = dbg_check_idx_size(c, c->old_idx_sz);
+	if (err)
+		goto out_lpt;
+
+	err = ubifs_replay_journal(c);
+	if (err)
+		goto out_journal;
+
+	err = ubifs_mount_orphans(c, c->need_recovery, mounted_read_only);
+	if (err)
+		goto out_orphans;
+
+	if (!mounted_read_only) {
+		int lnum;
+
+		/* Check for enough free space */
+		if (ubifs_calc_available(c, c->min_idx_lebs) <= 0) {
+			ubifs_err("insufficient available space");
+			err = -EINVAL;
+			goto out_orphans;
+		}
+
+		/* Check for enough log space */
+		lnum = c->lhead_lnum + 1;
+		if (lnum >= UBIFS_LOG_LNUM + c->log_lebs)
+			lnum = UBIFS_LOG_LNUM;
+		if (lnum == c->ltail_lnum) {
+			err = ubifs_consolidate_log(c);
+			if (err)
+				goto out_orphans;
+		}
+
+		if (c->need_recovery) {
+			err = ubifs_recover_size(c);
+			if (err)
+				goto out_orphans;
+			err = ubifs_rcvry_gc_commit(c);
+		} else
+			err = take_gc_lnum(c);
+		if (err)
+			goto out_orphans;
+
+		err = dbg_check_lprops(c);
+		if (err)
+			goto out_orphans;
+	} else if (c->need_recovery) {
+		err = ubifs_recover_size(c);
+		if (err)
+			goto out_orphans;
+	}
+
+	spin_lock(&ubifs_infos_lock);
+	list_add_tail(&c->infos_list, &ubifs_infos);
+	spin_unlock(&ubifs_infos_lock);
+
+	if (c->need_recovery) {
+		if (mounted_read_only)
+			ubifs_msg("recovery deferred");
+		else {
+			c->need_recovery = 0;
+			ubifs_msg("recovery completed");
+		}
+	}
+
+	err = dbg_check_filesystem(c);
+	if (err)
+		goto out_infos;
+
+	ubifs_msg("mounted UBI device %d, volume %d", c->vi.ubi_num,
+		  c->vi.vol_id);
+	if (mounted_read_only)
+		ubifs_msg("mounted read-only");
+	x = (long long)c->main_lebs * c->leb_size;
+	ubifs_msg("file system size: %lld bytes (%lld KiB, %lld MiB, %d LEBs)",
+		  x, x >> 10, x >> 20, c->main_lebs);
+	x = (long long)c->log_lebs * c->leb_size + c->max_bud_bytes;
+	ubifs_msg("journal size: %lld bytes (%lld KiB, %lld MiB, %d LEBs)",
+		  x, x >> 10, x >> 20, c->log_lebs + c->max_bud_cnt);
+	ubifs_msg("default compressor: %s", ubifs_compr_name(c->default_compr));
+	ubifs_msg("media format %d, latest format %d",
+		  c->fmt_version, UBIFS_FORMAT_VERSION);
+
+	dbg_msg("compiled on:         " __DATE__ " at " __TIME__);
+	dbg_msg("min. I/O unit size:  %d bytes", c->min_io_size);
+	dbg_msg("LEB size:            %d bytes (%d KiB)",
+		c->leb_size, c->leb_size / 1024);
+	dbg_msg("data journal heads:  %d",
+		c->jhead_cnt - NONDATA_JHEADS_CNT);
+	dbg_msg("UUID:                %02X%02X%02X%02X-%02X%02X"
+	       "-%02X%02X-%02X%02X-%02X%02X%02X%02X%02X%02X",
+	       c->uuid[0], c->uuid[1], c->uuid[2], c->uuid[3],
+	       c->uuid[4], c->uuid[5], c->uuid[6], c->uuid[7],
+	       c->uuid[8], c->uuid[9], c->uuid[10], c->uuid[11],
+	       c->uuid[12], c->uuid[13], c->uuid[14], c->uuid[15]);
+	dbg_msg("fast unmount:        %d", c->fast_unmount);
+	dbg_msg("big_lpt              %d", c->big_lpt);
+	dbg_msg("log LEBs:            %d (%d - %d)",
+		c->log_lebs, UBIFS_LOG_LNUM, c->log_last);
+	dbg_msg("LPT area LEBs:       %d (%d - %d)",
+		c->lpt_lebs, c->lpt_first, c->lpt_last);
+	dbg_msg("orphan area LEBs:    %d (%d - %d)",
+		c->orph_lebs, c->orph_first, c->orph_last);
+	dbg_msg("main area LEBs:      %d (%d - %d)",
+		c->main_lebs, c->main_first, c->leb_cnt - 1);
+	dbg_msg("index LEBs:          %d", c->lst.idx_lebs);
+	dbg_msg("total index bytes:   %lld (%lld KiB, %lld MiB)",
+		c->old_idx_sz, c->old_idx_sz >> 10, c->old_idx_sz >> 20);
+	dbg_msg("key hash type:       %d", c->key_hash_type);
+	dbg_msg("tree fanout:         %d", c->fanout);
+	dbg_msg("reserved GC LEB:     %d", c->gc_lnum);
+	dbg_msg("first main LEB:      %d", c->main_first);
+	dbg_msg("dead watermark:      %d", c->dead_wm);
+	dbg_msg("dark watermark:      %d", c->dark_wm);
+	x = (long long)c->main_lebs * c->dark_wm;
+	dbg_msg("max. dark space:     %lld (%lld KiB, %lld MiB)",
+		x, x >> 10, x >> 20);
+	dbg_msg("maximum bud bytes:   %lld (%lld KiB, %lld MiB)",
+		c->max_bud_bytes, c->max_bud_bytes >> 10,
+		c->max_bud_bytes >> 20);
+	dbg_msg("BG commit bud bytes: %lld (%lld KiB, %lld MiB)",
+		c->bg_bud_bytes, c->bg_bud_bytes >> 10,
+		c->bg_bud_bytes >> 20);
+	dbg_msg("current bud bytes    %lld (%lld KiB, %lld MiB)",
+		c->bud_bytes, c->bud_bytes >> 10, c->bud_bytes >> 20);
+	dbg_msg("max. seq. number:    %llu", c->max_sqnum);
+	dbg_msg("commit number:       %llu", c->cmt_no);
+
+	return 0;
+
+out_infos:
+	spin_lock(&ubifs_infos_lock);
+	list_del(&c->infos_list);
+	spin_unlock(&ubifs_infos_lock);
+out_orphans:
+	free_orphans(c);
+out_journal:
+	destroy_journal(c);
+out_lpt:
+	ubifs_lpt_free(c, 0);
+out_master:
+	kfree(c->mst_node);
+	kfree(c->rcvrd_mst_node);
+	if (c->bgt)
+		kthread_stop(c->bgt);
+out_wbufs:
+	free_wbufs(c);
+out_cbuf:
+	kfree(c->cbuf);
+out_dereg:
+	dbg_failure_mode_deregistration(c);
+out_free:
+	vfree(c->ileb_buf);
+	vfree(c->sbuf);
+	kfree(c->bottom_up_buf);
+	UBIFS_DBG(vfree(c->dbg_buf));
+	return err;
+}
+
+/**
+ * ubifs_umount - un-mount UBIFS file-system.
+ * @c: UBIFS file-system description object
+ *
+ * Note, this function is called to free allocated resourced when un-mounting,
+ * as well as free resources when an error occurred while we were half way
+ * through mounting (error path cleanup function). So it has to make sure the
+ * resource was actually allocated before freeing it.
+ */
+static void ubifs_umount(struct ubifs_info *c)
+{
+	dbg_gen("un-mounting UBI device %d, volume %d", c->vi.ubi_num,
+		c->vi.vol_id);
+
+	spin_lock(&ubifs_infos_lock);
+	list_del(&c->infos_list);
+	spin_unlock(&ubifs_infos_lock);
+
+	if (c->bgt)
+		kthread_stop(c->bgt);
+
+	destroy_journal(c);
+	free_wbufs(c);
+	free_orphans(c);
+	ubifs_lpt_free(c, 0);
+
+	kfree(c->cbuf);
+	kfree(c->rcvrd_mst_node);
+	kfree(c->mst_node);
+	vfree(c->sbuf);
+	kfree(c->bottom_up_buf);
+	UBIFS_DBG(vfree(c->dbg_buf));
+	vfree(c->ileb_buf);
+	dbg_failure_mode_deregistration(c);
+}
+
+/**
+ * ubifs_remount_rw - re-mount in read-write mode.
+ * @c: UBIFS file-system description object
+ *
+ * UBIFS avoids allocating many unnecessary resources when mounted in read-only
+ * mode. This function allocates the needed resources and re-mounts UBIFS in
+ * read-write mode.
+ */
+static int ubifs_remount_rw(struct ubifs_info *c)
+{
+	int err, lnum;
+
+	if (c->ro_media)
+		return -EINVAL;
+
+	mutex_lock(&c->umount_mutex);
+	c->remounting_rw = 1;
+
+	/* Check for enough free space */
+	if (ubifs_calc_available(c, c->min_idx_lebs) <= 0) {
+		ubifs_err("insufficient available space");
+		err = -EINVAL;
+		goto out;
+	}
+
+	if (c->old_leb_cnt != c->leb_cnt) {
+		struct ubifs_sb_node *sup;
+
+		sup = ubifs_read_sb_node(c);
+		if (IS_ERR(sup)) {
+			err = PTR_ERR(sup);
+			goto out;
+		}
+		sup->leb_cnt = cpu_to_le32(c->leb_cnt);
+		err = ubifs_write_sb_node(c, sup);
+		if (err)
+			goto out;
+	}
+
+	if (c->need_recovery) {
+		ubifs_msg("completing deferred recovery");
+		err = ubifs_write_rcvrd_mst_node(c);
+		if (err)
+			goto out;
+		err = ubifs_recover_size(c);
+		if (err)
+			goto out;
+		err = ubifs_clean_lebs(c, c->sbuf);
+		if (err)
+			goto out;
+		err = ubifs_recover_inl_heads(c, c->sbuf);
+		if (err)
+			goto out;
+	}
+
+	if (!(c->mst_node->flags & cpu_to_le32(UBIFS_MST_DIRTY))) {
+		c->mst_node->flags |= cpu_to_le32(UBIFS_MST_DIRTY);
+		err = ubifs_write_master(c);
+		if (err)
+			goto out;
+	}
+
+	c->ileb_buf = vmalloc(c->leb_size);
+	if (!c->ileb_buf) {
+		err = -ENOMEM;
+		goto out;
+	}
+
+	err = ubifs_lpt_init(c, 0, 1);
+	if (err)
+		goto out;
+
+	err = alloc_wbufs(c);
+	if (err)
+		goto out;
+
+	ubifs_create_buds_lists(c);
+
+	/* Create background thread */
+	c->bgt = kthread_create(ubifs_bg_thread, c, c->bgt_name);
+	if (!c->bgt)
+		c->bgt = ERR_PTR(-EINVAL);
+	if (IS_ERR(c->bgt)) {
+		err = PTR_ERR(c->bgt);
+		c->bgt = NULL;
+		ubifs_err("cannot spawn \"%s\", error %d",
+			  c->bgt_name, err);
+		return err;
+	}
+	wake_up_process(c->bgt);
+
+	c->orph_buf = vmalloc(c->leb_size);
+	if (!c->orph_buf)
+		return -ENOMEM;
+
+	/* Check for enough log space */
+	lnum = c->lhead_lnum + 1;
+	if (lnum >= UBIFS_LOG_LNUM + c->log_lebs)
+		lnum = UBIFS_LOG_LNUM;
+	if (lnum == c->ltail_lnum) {
+		err = ubifs_consolidate_log(c);
+		if (err)
+			goto out;
+	}
+
+	if (c->need_recovery)
+		err = ubifs_rcvry_gc_commit(c);
+	else
+		err = take_gc_lnum(c);
+	if (err)
+		goto out;
+
+	if (c->need_recovery) {
+		c->need_recovery = 0;
+		ubifs_msg("deferred recovery completed");
+	}
+
+	dbg_gen("re-mounted read-write");
+	c->vfs_sb->s_flags &= ~MS_RDONLY;
+	c->remounting_rw = 0;
+	mutex_unlock(&c->umount_mutex);
+	return 0;
+
+out:
+	vfree(c->orph_buf);
+	c->orph_buf = NULL;
+	if (c->bgt) {
+		kthread_stop(c->bgt);
+		c->bgt = NULL;
+	}
+	free_wbufs(c);
+	vfree(c->ileb_buf);
+	c->ileb_buf = NULL;
+	ubifs_lpt_free(c, 1);
+	c->remounting_rw = 0;
+	mutex_unlock(&c->umount_mutex);
+	return err;
+}
+
+/**
+ * commit_on_unmount - commit the journal when un-mounting.
+ * @c: UBIFS file-system description object
+ *
+ * This function is called during un-mounting and it commits the journal unless
+ * the "fast unmount" mode is enabled. It also avoids committing the journal if
+ * it contains too few data.
+ *
+ * Sometimes recovery requires the journal to be committed at least once, and
+ * this function takes care about this.
+ */
+static void commit_on_unmount(struct ubifs_info *c)
+{
+	if (!c->fast_unmount) {
+		long long bud_bytes;
+
+		spin_lock(&c->buds_lock);
+		bud_bytes = c->bud_bytes;
+		spin_unlock(&c->buds_lock);
+		if (bud_bytes > c->leb_size)
+			ubifs_run_commit(c);
+	}
+}
+
+/**
+ * ubifs_remount_ro - re-mount in read-only mode.
+ * @c: UBIFS file-system description object
+ *
+ * We rely on VFS to have stopped writing. Possibly the background thread could
+ * be running a commit, however kthread_stop will wait in that case.
+ */
+static void ubifs_remount_ro(struct ubifs_info *c)
+{
+	int i, err;
+
+	ubifs_assert(!c->need_recovery);
+	commit_on_unmount(c);
+
+	mutex_lock(&c->umount_mutex);
+	if (c->bgt) {
+		kthread_stop(c->bgt);
+		c->bgt = NULL;
+	}
+
+	for (i = 0; i < c->jhead_cnt; i++) {
+		ubifs_wbuf_sync(&c->jheads[i].wbuf);
+		del_timer_sync(&c->jheads[i].wbuf.timer);
+	}
+
+	if (!c->ro_media) {
+		c->mst_node->flags &= ~cpu_to_le32(UBIFS_MST_DIRTY);
+		c->mst_node->flags |= cpu_to_le32(UBIFS_MST_NO_ORPHS);
+		c->mst_node->gc_lnum = cpu_to_le32(c->gc_lnum);
+		err = ubifs_write_master(c);
+		if (err)
+			ubifs_ro_mode(c, err);
+	}
+
+	ubifs_destroy_idx_gc(c);
+	free_wbufs(c);
+	vfree(c->orph_buf);
+	c->orph_buf = NULL;
+	vfree(c->ileb_buf);
+	c->ileb_buf = NULL;
+	ubifs_lpt_free(c, 1);
+	mutex_unlock(&c->umount_mutex);
+}
+
+static void ubifs_put_super(struct super_block *sb)
+{
+	int i;
+	struct ubifs_info *c = sb->s_fs_info;
+
+	ubifs_msg("un-mount UBI device %d, volume %d", c->vi.ubi_num,
+		  c->vi.vol_id);
+	/*
+	 * The following asserts are only valid if there has not been a failure
+	 * of the media. For example, there will be dirty inodes if we failed
+	 * to write them back because of I/O errors.
+	 */
+	ubifs_assert(atomic_long_read(&c->dirty_pg_cnt) == 0);
+	ubifs_assert(c->budg_idx_growth == 0);
+	ubifs_assert(c->budg_data_growth == 0);
+
+	/*
+	 * The 'c->umount_lock' prevents races between UBIFS memory shrinker
+	 * and file system un-mount. Namely, it prevents the shrinker from
+	 * picking this superblock for shrinking - it will be just skipped if
+	 * the mutex is locked.
+	 */
+	mutex_lock(&c->umount_mutex);
+	if (!(c->vfs_sb->s_flags & MS_RDONLY)) {
+		/*
+		 * First of all kill the background thread to make sure it does
+		 * not interfere with un-mounting and freeing resources.
+		 */
+		if (c->bgt) {
+			kthread_stop(c->bgt);
+			c->bgt = NULL;
+		}
+
+		/* Synchronize write-buffers */
+		if (c->jheads)
+			for (i = 0; i < c->jhead_cnt; i++) {
+				ubifs_wbuf_sync(&c->jheads[i].wbuf);
+				del_timer_sync(&c->jheads[i].wbuf.timer);
+			}
+
+		/*
+		 * On fatal errors c->ro_media is set to 1, in which case we do
+		 * not write the master node.
+		 */
+		if (!c->ro_media) {
+			/*
+			 * We are being cleanly unmounted which means the
+			 * orphans were killed - indicate this in the master
+			 * node. Also save the reserved GC LEB number.
+			 */
+			int err;
+
+			c->mst_node->flags &= ~cpu_to_le32(UBIFS_MST_DIRTY);
+			c->mst_node->flags |= cpu_to_le32(UBIFS_MST_NO_ORPHS);
+			c->mst_node->gc_lnum = cpu_to_le32(c->gc_lnum);
+			err = ubifs_write_master(c);
+			if (err)
+				/*
+				 * Recovery will attempt to fix the master area
+				 * next mount, so we just print a message and
+				 * continue to unmount normally.
+				 */
+				ubifs_err("failed to write master node, "
+					  "error %d", err);
+		}
+	}
+
+	ubifs_umount(c);
+	bdi_destroy(&c->bdi);
+	ubi_close_volume(c->ubi);
+	mutex_unlock(&c->umount_mutex);
+	kfree(c);
+}
+
+static int ubifs_remount_fs(struct super_block *sb, int *flags, char *data)
+{
+	int err;
+	struct ubifs_info *c = sb->s_fs_info;
+
+	dbg_gen("old flags %#lx, new flags %#x", sb->s_flags, *flags);
+
+	err = ubifs_parse_options(c, data, 1);
+	if (err) {
+		ubifs_err("invalid or unknown remount parameter");
+		return err;
+	}
+	if ((sb->s_flags & MS_RDONLY) && !(*flags & MS_RDONLY)) {
+		err = ubifs_remount_rw(c);
+		if (err)
+			return err;
+	} else if (!(sb->s_flags & MS_RDONLY) && (*flags & MS_RDONLY))
+		ubifs_remount_ro(c);
+
+	return 0;
+}
+
+struct super_operations ubifs_super_operations = {
+	.alloc_inode   = ubifs_alloc_inode,
+	.destroy_inode = ubifs_destroy_inode,
+	.put_super     = ubifs_put_super,
+	.write_inode   = ubifs_write_inode,
+	.delete_inode  = ubifs_delete_inode,
+	.statfs        = ubifs_statfs,
+	.dirty_inode   = ubifs_dirty_inode,
+	.remount_fs    = ubifs_remount_fs,
+	.show_options  = ubifs_show_options,
+	.sync_fs       = ubifs_sync_fs,
+};
+
+/**
+ * open_ubi - parse UBI device name string and open the UBI device.
+ * @name: UBI volume name
+ * @mode: UBI volume open mode
+ *
+ * There are several ways to specify UBI volumes when mounting UBIFS:
+ * o ubiX_Y    - UBI device number X, volume Y;
+ * o ubiY      - UBI device number 0, volume Y;
+ * o ubiX:NAME - mount UBI device X, volume with name NAME;
+ * o ubi:NAME  - mount UBI device 0, volume with name NAME.
+ *
+ * Alternative '!' separator may be used instead of ':' (because some shells
+ * like busybox may interpret ':' as an NFS host name separator). This function
+ * returns ubi volume object in case of success and a negative error code in
+ * case of failure.
+ */
+static struct ubi_volume_desc *open_ubi(const char *name, int mode)
+{
+	int dev, vol;
+	char *endptr;
+
+	if (name[0] != 'u' || name[1] != 'b' || name[2] != 'i')
+		return ERR_PTR(-EINVAL);
+
+	/* ubi:NAME method */
+	if ((name[3] == ':' || name[3] == '!') && name[4] != '\0')
+		return ubi_open_volume_nm(0, name + 4, mode);
+
+	if (!isdigit(name[3]))
+		return ERR_PTR(-EINVAL);
+
+	dev = simple_strtoul(name + 3, &endptr, 0);
+
+	/* ubiY method */
+	if (*endptr == '\0')
+		return ubi_open_volume(0, dev, mode);
+
+	/* ubiX_Y method */
+	if (*endptr == '_' && isdigit(endptr[1])) {
+		vol = simple_strtoul(endptr + 1, &endptr, 0);
+		if (*endptr != '\0')
+			return ERR_PTR(-EINVAL);
+		return ubi_open_volume(dev, vol, mode);
+	}
+
+	/* ubiX:NAME method */
+	if ((*endptr == ':' || *endptr == '!') && endptr[1] != '\0')
+		return ubi_open_volume_nm(dev, ++endptr, mode);
+
+	return ERR_PTR(-EINVAL);
+}
+
+static int ubifs_fill_super(struct super_block *sb, void *data, int silent)
+{
+	struct ubi_volume_desc *ubi = sb->s_fs_info;
+	struct ubifs_info *c;
+	struct inode *root;
+	int err;
+
+	c = kzalloc(sizeof(struct ubifs_info), GFP_KERNEL);
+	if (!c)
+		return -ENOMEM;
+
+	spin_lock_init(&c->cnt_lock);
+	spin_lock_init(&c->cs_lock);
+	spin_lock_init(&c->buds_lock);
+	spin_lock_init(&c->space_lock);
+	spin_lock_init(&c->orphan_lock);
+	init_rwsem(&c->commit_sem);
+	mutex_init(&c->lp_mutex);
+	mutex_init(&c->tnc_mutex);
+	mutex_init(&c->log_mutex);
+	mutex_init(&c->mst_mutex);
+	mutex_init(&c->umount_mutex);
+	init_waitqueue_head(&c->cmt_wq);
+	c->buds = RB_ROOT;
+	c->old_idx = RB_ROOT;
+	c->size_tree = RB_ROOT;
+	c->orph_tree = RB_ROOT;
+	INIT_LIST_HEAD(&c->infos_list);
+	INIT_LIST_HEAD(&c->idx_gc);
+	INIT_LIST_HEAD(&c->replay_list);
+	INIT_LIST_HEAD(&c->replay_buds);
+	INIT_LIST_HEAD(&c->uncat_list);
+	INIT_LIST_HEAD(&c->empty_list);
+	INIT_LIST_HEAD(&c->freeable_list);
+	INIT_LIST_HEAD(&c->frdi_idx_list);
+	INIT_LIST_HEAD(&c->unclean_leb_list);
+	INIT_LIST_HEAD(&c->old_buds);
+	INIT_LIST_HEAD(&c->orph_list);
+	INIT_LIST_HEAD(&c->orph_new);
+
+	c->highest_inum = UBIFS_FIRST_INO;
+	get_random_bytes(&c->vfs_gen, sizeof(int));
+	c->lhead_lnum = c->ltail_lnum = UBIFS_LOG_LNUM;
+
+	ubi_get_volume_info(ubi, &c->vi);
+	ubi_get_device_info(c->vi.ubi_num, &c->di);
+
+	/* Re-open the UBI device in read-write mode */
+	c->ubi = ubi_open_volume(c->vi.ubi_num, c->vi.vol_id, UBI_READWRITE);
+	if (IS_ERR(c->ubi)) {
+		err = PTR_ERR(c->ubi);
+		goto out_free;
+	}
+
+	/*
+	 * UBIFS provids 'backing_dev_info' in order to disable readahead. For
+	 * UBIFS, I/O is not deferred, it is done immediately in readpage,
+	 * which means the user would have to wait not just for their own I/O
+	 * but the readahead I/O as well i.e. completely pointless.
+	 *
+	 * Read-ahead will be disabled because @c->bdi.ra_pages is 0.
+	 */
+	c->bdi.capabilities = BDI_CAP_MAP_COPY;
+	c->bdi.unplug_io_fn = default_unplug_io_fn;
+	err  = bdi_init(&c->bdi);
+	if (err)
+		goto out_close;
+
+	err = ubifs_parse_options(c, data, 0);
+	if (err)
+		goto out_bdi;
+
+	c->vfs_sb = sb;
+
+	sb->s_fs_info = c;
+	sb->s_magic = UBIFS_SUPER_MAGIC;
+	sb->s_blocksize = UBIFS_BLOCK_SIZE;
+	sb->s_blocksize_bits = UBIFS_BLOCK_SHIFT;
+	sb->s_dev = c->vi.cdev;
+	sb->s_maxbytes = c->max_inode_sz = key_max_inode_size(c);
+	if (c->max_inode_sz > MAX_LFS_FILESIZE)
+		sb->s_maxbytes = c->max_inode_sz = MAX_LFS_FILESIZE;
+	sb->s_op = &ubifs_super_operations;
+
+	mutex_lock(&c->umount_mutex);
+	err = mount_ubifs(c);
+	if (err) {
+		ubifs_assert(err < 0);
+		goto out_unlock;
+	}
+
+	/* Read the root inode */
+	root = ubifs_iget(sb, UBIFS_ROOT_INO);
+	if (IS_ERR(root)) {
+		err = PTR_ERR(root);
+		goto out_umount;
+	}
+
+	sb->s_root = d_alloc_root(root);
+	if (!sb->s_root)
+		goto out_iput;
+
+	mutex_unlock(&c->umount_mutex);
+
+	return 0;
+
+out_iput:
+	iput(root);
+out_umount:
+	ubifs_umount(c);
+out_unlock:
+	mutex_unlock(&c->umount_mutex);
+out_bdi:
+	bdi_destroy(&c->bdi);
+out_close:
+	ubi_close_volume(c->ubi);
+out_free:
+	kfree(c);
+	return err;
+}
+
+static int sb_test(struct super_block *sb, void *data)
+{
+	dev_t *dev = data;
+
+	return sb->s_dev == *dev;
+}
+
+static int sb_set(struct super_block *sb, void *data)
+{
+	dev_t *dev = data;
+
+	sb->s_dev = *dev;
+	return 0;
+}
+
+static int ubifs_get_sb(struct file_system_type *fs_type, int flags,
+			const char *name, void *data, struct vfsmount *mnt)
+{
+	struct ubi_volume_desc *ubi;
+	struct ubi_volume_info vi;
+	struct super_block *sb;
+	int err;
+
+	dbg_gen("name %s, flags %#x", name, flags);
+
+	/*
+	 * Get UBI device number and volume ID. Mount it read-only so far
+	 * because this might be a new mount point, and UBI allows only one
+	 * read-write user at a time.
+	 */
+	ubi = open_ubi(name, UBI_READONLY);
+	if (IS_ERR(ubi)) {
+		ubifs_err("cannot open \"%s\", error %d",
+			  name, (int)PTR_ERR(ubi));
+		return PTR_ERR(ubi);
+	}
+	ubi_get_volume_info(ubi, &vi);
+
+	dbg_gen("opened ubi%d_%d", vi.ubi_num, vi.vol_id);
+
+	sb = sget(fs_type, &sb_test, &sb_set, &vi.cdev);
+	if (IS_ERR(sb)) {
+		err = PTR_ERR(sb);
+		goto out_close;
+	}
+
+	if (sb->s_root) {
+		/* A new mount point for already mounted UBIFS */
+		dbg_gen("this ubi volume is already mounted");
+		if ((flags ^ sb->s_flags) & MS_RDONLY) {
+			err = -EBUSY;
+			goto out_deact;
+		}
+	} else {
+		sb->s_flags = flags;
+		/*
+		 * Pass 'ubi' to 'fill_super()' in sb->s_fs_info where it is
+		 * replaced by 'c'.
+		 */
+		sb->s_fs_info = ubi;
+		err = ubifs_fill_super(sb, data, flags & MS_SILENT ? 1 : 0);
+		if (err)
+			goto out_deact;
+		/* We do not support atime */
+		sb->s_flags |= MS_ACTIVE | MS_NOATIME;
+	}
+
+	/* 'fill_super()' opens ubi again so we must close it here */
+	ubi_close_volume(ubi);
+
+	return simple_set_mnt(mnt, sb);
+
+out_deact:
+	up_write(&sb->s_umount);
+	deactivate_super(sb);
+out_close:
+	ubi_close_volume(ubi);
+	return err;
+}
+
+static void ubifs_kill_sb(struct super_block *sb)
+{
+	struct ubifs_info *c = sb->s_fs_info;
+
+	/*
+	 * We do 'commit_on_unmount()' here instead of 'ubifs_put_super()'
+	 * in order to be outside BKL.
+	 */
+	if (sb->s_root && !(sb->s_flags & MS_RDONLY))
+		commit_on_unmount(c);
+	/* The un-mount routine is actually done in put_super() */
+	generic_shutdown_super(sb);
+}
+
+static struct file_system_type ubifs_fs_type = {
+	.name    = "ubifs",
+	.owner   = THIS_MODULE,
+	.get_sb  = ubifs_get_sb,
+	.kill_sb = ubifs_kill_sb
+};
+
+/*
+ * Inode slab cache constructor.
+ */
+static void inode_slab_ctor(struct kmem_cache *cachep, void *obj)
+{
+	struct ubifs_inode *ui = obj;
+	inode_init_once(&ui->vfs_inode);
+}
+
+static int __init ubifs_init(void)
+{
+	int err;
+
+	BUILD_BUG_ON(sizeof(struct ubifs_ch) != 24);
+
+	/* Make sure node sizes are 8-byte aligned */
+	BUILD_BUG_ON(UBIFS_CH_SZ        & 7);
+	BUILD_BUG_ON(UBIFS_INO_NODE_SZ  & 7);
+	BUILD_BUG_ON(UBIFS_DENT_NODE_SZ & 7);
+	BUILD_BUG_ON(UBIFS_XENT_NODE_SZ & 7);
+	BUILD_BUG_ON(UBIFS_DATA_NODE_SZ & 7);
+	BUILD_BUG_ON(UBIFS_TRUN_NODE_SZ & 7);
+	BUILD_BUG_ON(UBIFS_SB_NODE_SZ   & 7);
+	BUILD_BUG_ON(UBIFS_MST_NODE_SZ  & 7);
+	BUILD_BUG_ON(UBIFS_REF_NODE_SZ  & 7);
+	BUILD_BUG_ON(UBIFS_CS_NODE_SZ   & 7);
+	BUILD_BUG_ON(UBIFS_ORPH_NODE_SZ & 7);
+
+	BUILD_BUG_ON(UBIFS_MAX_DENT_NODE_SZ & 7);
+	BUILD_BUG_ON(UBIFS_MAX_XENT_NODE_SZ & 7);
+	BUILD_BUG_ON(UBIFS_MAX_DATA_NODE_SZ & 7);
+	BUILD_BUG_ON(UBIFS_MAX_INO_NODE_SZ  & 7);
+	BUILD_BUG_ON(UBIFS_MAX_NODE_SZ      & 7);
+	BUILD_BUG_ON(MIN_WRITE_SZ           & 7);
+
+	/* Check min. node size */
+	BUILD_BUG_ON(UBIFS_INO_NODE_SZ  < MIN_WRITE_SZ);
+	BUILD_BUG_ON(UBIFS_DENT_NODE_SZ < MIN_WRITE_SZ);
+	BUILD_BUG_ON(UBIFS_XENT_NODE_SZ < MIN_WRITE_SZ);
+	BUILD_BUG_ON(UBIFS_TRUN_NODE_SZ < MIN_WRITE_SZ);
+
+	BUILD_BUG_ON(UBIFS_MAX_DENT_NODE_SZ > UBIFS_MAX_NODE_SZ);
+	BUILD_BUG_ON(UBIFS_MAX_XENT_NODE_SZ > UBIFS_MAX_NODE_SZ);
+	BUILD_BUG_ON(UBIFS_MAX_DATA_NODE_SZ > UBIFS_MAX_NODE_SZ);
+	BUILD_BUG_ON(UBIFS_MAX_INO_NODE_SZ  > UBIFS_MAX_NODE_SZ);
+
+	/* Defined node sizes */
+	BUILD_BUG_ON(UBIFS_SB_NODE_SZ  != 4096);
+	BUILD_BUG_ON(UBIFS_MST_NODE_SZ != 512);
+	BUILD_BUG_ON(UBIFS_INO_NODE_SZ != 160);
+	BUILD_BUG_ON(UBIFS_REF_NODE_SZ != 64);
+
+	/*
+	 * We require that PAGE_CACHE_SIZE is greater-than-or-equal-to
+	 * UBIFS_BLOCK_SIZE. It is assumed that both are powers of 2.
+	 */
+	if (PAGE_CACHE_SIZE < UBIFS_BLOCK_SIZE) {
+		ubifs_err("VFS page cache size is %u bytes, but UBIFS requires"
+			  " at least 4096 bytes",
+			  (unsigned int)PAGE_CACHE_SIZE);
+		return -EINVAL;
+	}
+
+	err = register_filesystem(&ubifs_fs_type);
+	if (err) {
+		ubifs_err("cannot register file system, error %d", err);
+		return err;
+	}
+
+	err = -ENOMEM;
+	ubifs_inode_slab = kmem_cache_create("ubifs_inode_slab",
+				sizeof(struct ubifs_inode), 0,
+				SLAB_MEM_SPREAD | SLAB_RECLAIM_ACCOUNT,
+				&inode_slab_ctor);
+	if (!ubifs_inode_slab)
+		goto out_reg;
+
+	register_shrinker(&ubifs_shrinker_info);
+
+	err = ubifs_compressors_init();
+	if (err)
+		goto out_compr;
+
+	return 0;
+
+out_compr:
+	unregister_shrinker(&ubifs_shrinker_info);
+	kmem_cache_destroy(ubifs_inode_slab);
+out_reg:
+	unregister_filesystem(&ubifs_fs_type);
+	return err;
+}
+/* late_initcall to let compressors initialize first */
+late_initcall(ubifs_init);
+
+static void __exit ubifs_exit(void)
+{
+	ubifs_assert(list_empty(&ubifs_infos));
+	ubifs_assert(atomic_long_read(&ubifs_clean_zn_cnt) == 0);
+
+	ubifs_compressors_exit();
+	unregister_shrinker(&ubifs_shrinker_info);
+	kmem_cache_destroy(ubifs_inode_slab);
+	unregister_filesystem(&ubifs_fs_type);
+}
+module_exit(ubifs_exit);
+
+MODULE_LICENSE("GPL");
+MODULE_VERSION(__stringify(UBIFS_VERSION));
+MODULE_AUTHOR("Artem Bityutskiy, Adrian Hunter");
+MODULE_DESCRIPTION("UBIFS - UBI File System");
diff --git a/fs/ubifs/tnc.c b/fs/ubifs/tnc.c
new file mode 100644
index 00000000000..e909f4a9644
--- /dev/null
+++ b/fs/ubifs/tnc.c
@@ -0,0 +1,2956 @@
+/*
+ * This file is part of UBIFS.
+ *
+ * Copyright (C) 2006-2008 Nokia Corporation.
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 as published by
+ * the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
+ * more details.
+ *
+ * You should have received a copy of the GNU General Public License along with
+ * this program; if not, write to the Free Software Foundation, Inc., 51
+ * Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
+ *
+ * Authors: Adrian Hunter
+ *          Artem Bityutskiy (Битюцкий Артём)
+ */
+
+/*
+ * This file implements TNC (Tree Node Cache) which caches indexing nodes of
+ * the UBIFS B-tree.
+ *
+ * At the moment the locking rules of the TNC tree are quite simple and
+ * straightforward. We just have a mutex and lock it when we traverse the
+ * tree. If a znode is not in memory, we read it from flash while still having
+ * the mutex locked.
+ */
+
+#include <linux/crc32.h>
+#include "ubifs.h"
+
+/*
+ * Returned codes of 'matches_name()' and 'fallible_matches_name()' functions.
+ * @NAME_LESS: name corresponding to the first argument is less than second
+ * @NAME_MATCHES: names match
+ * @NAME_GREATER: name corresponding to the second argument is greater than
+ *                first
+ * @NOT_ON_MEDIA: node referred by zbranch does not exist on the media
+ *
+ * These constants were introduce to improve readability.
+ */
+enum {
+	NAME_LESS    = 0,
+	NAME_MATCHES = 1,
+	NAME_GREATER = 2,
+	NOT_ON_MEDIA = 3,
+};
+
+/**
+ * insert_old_idx - record an index node obsoleted since the last commit start.
+ * @c: UBIFS file-system description object
+ * @lnum: LEB number of obsoleted index node
+ * @offs: offset of obsoleted index node
+ *
+ * Returns %0 on success, and a negative error code on failure.
+ *
+ * For recovery, there must always be a complete intact version of the index on
+ * flash at all times. That is called the "old index". It is the index as at the
+ * time of the last successful commit. Many of the index nodes in the old index
+ * may be dirty, but they must not be erased until the next successful commit
+ * (at which point that index becomes the old index).
+ *
+ * That means that the garbage collection and the in-the-gaps method of
+ * committing must be able to determine if an index node is in the old index.
+ * Most of the old index nodes can be found by looking up the TNC using the
+ * 'lookup_znode()' function. However, some of the old index nodes may have
+ * been deleted from the current index or may have been changed so much that
+ * they cannot be easily found. In those cases, an entry is added to an RB-tree.
+ * That is what this function does. The RB-tree is ordered by LEB number and
+ * offset because they uniquely identify the old index node.
+ */
+static int insert_old_idx(struct ubifs_info *c, int lnum, int offs)
+{
+	struct ubifs_old_idx *old_idx, *o;
+	struct rb_node **p, *parent = NULL;
+
+	old_idx = kmalloc(sizeof(struct ubifs_old_idx), GFP_NOFS);
+	if (unlikely(!old_idx))
+		return -ENOMEM;
+	old_idx->lnum = lnum;
+	old_idx->offs = offs;
+
+	p = &c->old_idx.rb_node;
+	while (*p) {
+		parent = *p;
+		o = rb_entry(parent, struct ubifs_old_idx, rb);
+		if (lnum < o->lnum)
+			p = &(*p)->rb_left;
+		else if (lnum > o->lnum)
+			p = &(*p)->rb_right;
+		else if (offs < o->offs)
+			p = &(*p)->rb_left;
+		else if (offs > o->offs)
+			p = &(*p)->rb_right;
+		else {
+			ubifs_err("old idx added twice!");
+			kfree(old_idx);
+			return 0;
+		}
+	}
+	rb_link_node(&old_idx->rb, parent, p);
+	rb_insert_color(&old_idx->rb, &c->old_idx);
+	return 0;
+}
+
+/**
+ * insert_old_idx_znode - record a znode obsoleted since last commit start.
+ * @c: UBIFS file-system description object
+ * @znode: znode of obsoleted index node
+ *
+ * Returns %0 on success, and a negative error code on failure.
+ */
+int insert_old_idx_znode(struct ubifs_info *c, struct ubifs_znode *znode)
+{
+	if (znode->parent) {
+		struct ubifs_zbranch *zbr;
+
+		zbr = &znode->parent->zbranch[znode->iip];
+		if (zbr->len)
+			return insert_old_idx(c, zbr->lnum, zbr->offs);
+	} else
+		if (c->zroot.len)
+			return insert_old_idx(c, c->zroot.lnum,
+					      c->zroot.offs);
+	return 0;
+}
+
+/**
+ * ins_clr_old_idx_znode - record a znode obsoleted since last commit start.
+ * @c: UBIFS file-system description object
+ * @znode: znode of obsoleted index node
+ *
+ * Returns %0 on success, and a negative error code on failure.
+ */
+static int ins_clr_old_idx_znode(struct ubifs_info *c,
+				 struct ubifs_znode *znode)
+{
+	int err;
+
+	if (znode->parent) {
+		struct ubifs_zbranch *zbr;
+
+		zbr = &znode->parent->zbranch[znode->iip];
+		if (zbr->len) {
+			err = insert_old_idx(c, zbr->lnum, zbr->offs);
+			if (err)
+				return err;
+			zbr->lnum = 0;
+			zbr->offs = 0;
+			zbr->len = 0;
+		}
+	} else
+		if (c->zroot.len) {
+			err = insert_old_idx(c, c->zroot.lnum, c->zroot.offs);
+			if (err)
+				return err;
+			c->zroot.lnum = 0;
+			c->zroot.offs = 0;
+			c->zroot.len = 0;
+		}
+	return 0;
+}
+
+/**
+ * destroy_old_idx - destroy the old_idx RB-tree.
+ * @c: UBIFS file-system description object
+ *
+ * During start commit, the old_idx RB-tree is used to avoid overwriting index
+ * nodes that were in the index last commit but have since been deleted.  This
+ * is necessary for recovery i.e. the old index must be kept intact until the
+ * new index is successfully written.  The old-idx RB-tree is used for the
+ * in-the-gaps method of writing index nodes and is destroyed every commit.
+ */
+void destroy_old_idx(struct ubifs_info *c)
+{
+	struct rb_node *this = c->old_idx.rb_node;
+	struct ubifs_old_idx *old_idx;
+
+	while (this) {
+		if (this->rb_left) {
+			this = this->rb_left;
+			continue;
+		} else if (this->rb_right) {
+			this = this->rb_right;
+			continue;
+		}
+		old_idx = rb_entry(this, struct ubifs_old_idx, rb);
+		this = rb_parent(this);
+		if (this) {
+			if (this->rb_left == &old_idx->rb)
+				this->rb_left = NULL;
+			else
+				this->rb_right = NULL;
+		}
+		kfree(old_idx);
+	}
+	c->old_idx = RB_ROOT;
+}
+
+/**
+ * copy_znode - copy a dirty znode.
+ * @c: UBIFS file-system description object
+ * @znode: znode to copy
+ *
+ * A dirty znode being committed may not be changed, so it is copied.
+ */
+static struct ubifs_znode *copy_znode(struct ubifs_info *c,
+				      struct ubifs_znode *znode)
+{
+	struct ubifs_znode *zn;
+
+	zn = kmalloc(c->max_znode_sz, GFP_NOFS);
+	if (unlikely(!zn))
+		return ERR_PTR(-ENOMEM);
+
+	memcpy(zn, znode, c->max_znode_sz);
+	zn->cnext = NULL;
+	__set_bit(DIRTY_ZNODE, &zn->flags);
+	__clear_bit(COW_ZNODE, &zn->flags);
+
+	ubifs_assert(!test_bit(OBSOLETE_ZNODE, &znode->flags));
+	__set_bit(OBSOLETE_ZNODE, &znode->flags);
+
+	if (znode->level != 0) {
+		int i;
+		const int n = zn->child_cnt;
+
+		/* The children now have new parent */
+		for (i = 0; i < n; i++) {
+			struct ubifs_zbranch *zbr = &zn->zbranch[i];
+
+			if (zbr->znode)
+				zbr->znode->parent = zn;
+		}
+	}
+
+	atomic_long_inc(&c->dirty_zn_cnt);
+	return zn;
+}
+
+/**
+ * add_idx_dirt - add dirt due to a dirty znode.
+ * @c: UBIFS file-system description object
+ * @lnum: LEB number of index node
+ * @dirt: size of index node
+ *
+ * This function updates lprops dirty space and the new size of the index.
+ */
+static int add_idx_dirt(struct ubifs_info *c, int lnum, int dirt)
+{
+	c->calc_idx_sz -= ALIGN(dirt, 8);
+	return ubifs_add_dirt(c, lnum, dirt);
+}
+
+/**
+ * dirty_cow_znode - ensure a znode is not being committed.
+ * @c: UBIFS file-system description object
+ * @zbr: branch of znode to check
+ *
+ * Returns dirtied znode on success or negative error code on failure.
+ */
+static struct ubifs_znode *dirty_cow_znode(struct ubifs_info *c,
+					   struct ubifs_zbranch *zbr)
+{
+	struct ubifs_znode *znode = zbr->znode;
+	struct ubifs_znode *zn;
+	int err;
+
+	if (!test_bit(COW_ZNODE, &znode->flags)) {
+		/* znode is not being committed */
+		if (!test_and_set_bit(DIRTY_ZNODE, &znode->flags)) {
+			atomic_long_inc(&c->dirty_zn_cnt);
+			atomic_long_dec(&c->clean_zn_cnt);
+			atomic_long_dec(&ubifs_clean_zn_cnt);
+			err = add_idx_dirt(c, zbr->lnum, zbr->len);
+			if (unlikely(err))
+				return ERR_PTR(err);
+		}
+		return znode;
+	}
+
+	zn = copy_znode(c, znode);
+	if (unlikely(IS_ERR(zn)))
+		return zn;
+
+	if (zbr->len) {
+		err = insert_old_idx(c, zbr->lnum, zbr->offs);
+		if (unlikely(err))
+			return ERR_PTR(err);
+		err = add_idx_dirt(c, zbr->lnum, zbr->len);
+	} else
+		err = 0;
+
+	zbr->znode = zn;
+	zbr->lnum = 0;
+	zbr->offs = 0;
+	zbr->len = 0;
+
+	if (unlikely(err))
+		return ERR_PTR(err);
+	return zn;
+}
+
+/**
+ * lnc_add - add a leaf node to the leaf node cache.
+ * @c: UBIFS file-system description object
+ * @zbr: zbranch of leaf node
+ * @node: leaf node
+ *
+ * Leaf nodes are non-index nodes directory entry nodes or data nodes. The
+ * purpose of the leaf node cache is to save re-reading the same leaf node over
+ * and over again. Most things are cached by VFS, however the file system must
+ * cache directory entries for readdir and for resolving hash collisions. The
+ * present implementation of the leaf node cache is extremely simple, and
+ * allows for error returns that are not used but that may be needed if a more
+ * complex implementation is created.
+ *
+ * Note, this function does not add the @node object to LNC directly, but
+ * allocates a copy of the object and adds the copy to LNC. The reason for this
+ * is that @node has been allocated outside of the TNC subsystem and will be
+ * used with @c->tnc_mutex unlock upon return from the TNC subsystem. But LNC
+ * may be changed at any time, e.g. freed by the shrinker.
+ */
+static int lnc_add(struct ubifs_info *c, struct ubifs_zbranch *zbr,
+		   const void *node)
+{
+	int err;
+	void *lnc_node;
+	const struct ubifs_dent_node *dent = node;
+
+	ubifs_assert(!zbr->leaf);
+	ubifs_assert(zbr->len != 0);
+	ubifs_assert(is_hash_key(c, &zbr->key));
+
+	err = ubifs_validate_entry(c, dent);
+	if (err) {
+		dbg_dump_stack();
+		dbg_dump_node(c, dent);
+		return err;
+	}
+
+	lnc_node = kmalloc(zbr->len, GFP_NOFS);
+	if (!lnc_node)
+		/* We don't have to have the cache, so no error */
+		return 0;
+
+	memcpy(lnc_node, node, zbr->len);
+	zbr->leaf = lnc_node;
+	return 0;
+}
+
+ /**
+ * lnc_add_directly - add a leaf node to the leaf-node-cache.
+ * @c: UBIFS file-system description object
+ * @zbr: zbranch of leaf node
+ * @node: leaf node
+ *
+ * This function is similar to 'lnc_add()', but it does not create a copy of
+ * @node but inserts @node to TNC directly.
+ */
+static int lnc_add_directly(struct ubifs_info *c, struct ubifs_zbranch *zbr,
+			    void *node)
+{
+	int err;
+
+	ubifs_assert(!zbr->leaf);
+	ubifs_assert(zbr->len != 0);
+
+	err = ubifs_validate_entry(c, node);
+	if (err) {
+		dbg_dump_stack();
+		dbg_dump_node(c, node);
+		return err;
+	}
+
+	zbr->leaf = node;
+	return 0;
+}
+
+/**
+ * lnc_free - remove a leaf node from the leaf node cache.
+ * @zbr: zbranch of leaf node
+ * @node: leaf node
+ */
+static void lnc_free(struct ubifs_zbranch *zbr)
+{
+	if (!zbr->leaf)
+		return;
+	kfree(zbr->leaf);
+	zbr->leaf = NULL;
+}
+
+/**
+ * tnc_read_node_nm - read a "hashed" leaf node.
+ * @c: UBIFS file-system description object
+ * @zbr: key and position of the node
+ * @node: node is returned here
+ *
+ * This function reads a "hashed" node defined by @zbr from the leaf node cache
+ * (in it is there) or from the hash media, in which case the node is also
+ * added to LNC. Returns zero in case of success or a negative negative error
+ * code in case of failure.
+ */
+static int tnc_read_node_nm(struct ubifs_info *c, struct ubifs_zbranch *zbr,
+			    void *node)
+{
+	int err;
+
+	ubifs_assert(is_hash_key(c, &zbr->key));
+
+	if (zbr->leaf) {
+		/* Read from the leaf node cache */
+		ubifs_assert(zbr->len != 0);
+		memcpy(node, zbr->leaf, zbr->len);
+		return 0;
+	}
+
+	err = ubifs_tnc_read_node(c, zbr, node);
+	if (err)
+		return err;
+
+	/* Add the node to the leaf node cache */
+	err = lnc_add(c, zbr, node);
+	return err;
+}
+
+/**
+ * try_read_node - read a node if it is a node.
+ * @c: UBIFS file-system description object
+ * @buf: buffer to read to
+ * @type: node type
+ * @len: node length (not aligned)
+ * @lnum: LEB number of node to read
+ * @offs: offset of node to read
+ *
+ * This function tries to read a node of known type and length, checks it and
+ * stores it in @buf. This function returns %1 if a node is present and %0 if
+ * a node is not present. A negative error code is returned for I/O errors.
+ * This function performs that same function as ubifs_read_node except that
+ * it does not require that there is actually a node present and instead
+ * the return code indicates if a node was read.
+ */
+static int try_read_node(const struct ubifs_info *c, void *buf, int type,
+			 int len, int lnum, int offs)
+{
+	int err, node_len;
+	struct ubifs_ch *ch = buf;
+	uint32_t crc, node_crc;
+
+	dbg_io("LEB %d:%d, %s, length %d", lnum, offs, dbg_ntype(type), len);
+
+	err = ubi_read(c->ubi, lnum, buf, offs, len);
+	if (err) {
+		ubifs_err("cannot read node type %d from LEB %d:%d, error %d",
+			  type, lnum, offs, err);
+		return err;
+	}
+
+	if (le32_to_cpu(ch->magic) != UBIFS_NODE_MAGIC)
+		return 0;
+
+	if (ch->node_type != type)
+		return 0;
+
+	node_len = le32_to_cpu(ch->len);
+	if (node_len != len)
+		return 0;
+
+	crc = crc32(UBIFS_CRC32_INIT, buf + 8, node_len - 8);
+	node_crc = le32_to_cpu(ch->crc);
+	if (crc != node_crc)
+		return 0;
+
+	return 1;
+}
+
+/**
+ * fallible_read_node - try to read a leaf node.
+ * @c: UBIFS file-system description object
+ * @key:  key of node to read
+ * @zbr:  position of node
+ * @node: node returned
+ *
+ * This function tries to read a node and returns %1 if the node is read, %0
+ * if the node is not present, and a negative error code in the case of error.
+ */
+static int fallible_read_node(struct ubifs_info *c, const union ubifs_key *key,
+			      struct ubifs_zbranch *zbr, void *node)
+{
+	int ret;
+
+	dbg_tnc("LEB %d:%d, key %s", zbr->lnum, zbr->offs, DBGKEY(key));
+
+	ret = try_read_node(c, node, key_type(c, key), zbr->len, zbr->lnum,
+			    zbr->offs);
+	if (ret == 1) {
+		union ubifs_key node_key;
+		struct ubifs_dent_node *dent = node;
+
+		/* All nodes have key in the same place */
+		key_read(c, &dent->key, &node_key);
+		if (keys_cmp(c, key, &node_key) != 0)
+			ret = 0;
+	}
+	if (ret == 0)
+		dbg_mnt("dangling branch LEB %d:%d len %d, key %s",
+			zbr->lnum, zbr->offs, zbr->len, DBGKEY(key));
+	return ret;
+}
+
+/**
+ * matches_name - determine if a direntry or xattr entry matches a given name.
+ * @c: UBIFS file-system description object
+ * @zbr: zbranch of dent
+ * @nm: name to match
+ *
+ * This function checks if xentry/direntry referred by zbranch @zbr matches name
+ * @nm. Returns %NAME_MATCHES if it does, %NAME_LESS if the name referred by
+ * @zbr is less than @nm, and %NAME_GREATER if it is greater than @nm. In case
+ * of failure, a negative error code is returned.
+ */
+static int matches_name(struct ubifs_info *c, struct ubifs_zbranch *zbr,
+			const struct qstr *nm)
+{
+	struct ubifs_dent_node *dent;
+	int nlen, err;
+
+	/* If possible, match against the dent in the leaf node cache */
+	if (!zbr->leaf) {
+		dent = kmalloc(zbr->len, GFP_NOFS);
+		if (!dent)
+			return -ENOMEM;
+
+		err = ubifs_tnc_read_node(c, zbr, dent);
+		if (err)
+			goto out_free;
+
+		/* Add the node to the leaf node cache */
+		err = lnc_add_directly(c, zbr, dent);
+		if (err)
+			goto out_free;
+	} else
+		dent = zbr->leaf;
+
+	nlen = le16_to_cpu(dent->nlen);
+	err = memcmp(dent->name, nm->name, min_t(int, nlen, nm->len));
+	if (err == 0) {
+		if (nlen == nm->len)
+			return NAME_MATCHES;
+		else if (nlen < nm->len)
+			return NAME_LESS;
+		else
+			return NAME_GREATER;
+	} else if (err < 0)
+		return NAME_LESS;
+	else
+		return NAME_GREATER;
+
+out_free:
+	kfree(dent);
+	return err;
+}
+
+/**
+ * get_znode - get a TNC znode that may not be loaded yet.
+ * @c: UBIFS file-system description object
+ * @znode: parent znode
+ * @n: znode branch slot number
+ *
+ * This function returns the znode or a negative error code.
+ */
+static struct ubifs_znode *get_znode(struct ubifs_info *c,
+				     struct ubifs_znode *znode, int n)
+{
+	struct ubifs_zbranch *zbr;
+
+	zbr = &znode->zbranch[n];
+	if (zbr->znode)
+		znode = zbr->znode;
+	else
+		znode = ubifs_load_znode(c, zbr, znode, n);
+	return znode;
+}
+
+/**
+ * tnc_next - find next TNC entry.
+ * @c: UBIFS file-system description object
+ * @zn: znode is passed and returned here
+ * @n: znode branch slot number is passed and returned here
+ *
+ * This function returns %0 if the next TNC entry is found, %-ENOENT if there is
+ * no next entry, or a negative error code otherwise.
+ */
+static int tnc_next(struct ubifs_info *c, struct ubifs_znode **zn, int *n)
+{
+	struct ubifs_znode *znode = *zn;
+	int nn = *n;
+
+	nn += 1;
+	if (nn < znode->child_cnt) {
+		*n = nn;
+		return 0;
+	}
+	while (1) {
+		struct ubifs_znode *zp;
+
+		zp = znode->parent;
+		if (!zp)
+			return -ENOENT;
+		nn = znode->iip + 1;
+		znode = zp;
+		if (nn < znode->child_cnt) {
+			znode = get_znode(c, znode, nn);
+			if (IS_ERR(znode))
+				return PTR_ERR(znode);
+			while (znode->level != 0) {
+				znode = get_znode(c, znode, 0);
+				if (IS_ERR(znode))
+					return PTR_ERR(znode);
+			}
+			nn = 0;
+			break;
+		}
+	}
+	*zn = znode;
+	*n = nn;
+	return 0;
+}
+
+/**
+ * tnc_prev - find previous TNC entry.
+ * @c: UBIFS file-system description object
+ * @zn: znode is returned here
+ * @n: znode branch slot number is passed and returned here
+ *
+ * This function returns %0 if the previous TNC entry is found, %-ENOENT if
+ * there is no next entry, or a negative error code otherwise.
+ */
+static int tnc_prev(struct ubifs_info *c, struct ubifs_znode **zn, int *n)
+{
+	struct ubifs_znode *znode = *zn;
+	int nn = *n;
+
+	if (nn > 0) {
+		*n = nn - 1;
+		return 0;
+	}
+	while (1) {
+		struct ubifs_znode *zp;
+
+		zp = znode->parent;
+		if (!zp)
+			return -ENOENT;
+		nn = znode->iip - 1;
+		znode = zp;
+		if (nn >= 0) {
+			znode = get_znode(c, znode, nn);
+			if (IS_ERR(znode))
+				return PTR_ERR(znode);
+			while (znode->level != 0) {
+				nn = znode->child_cnt - 1;
+				znode = get_znode(c, znode, nn);
+				if (IS_ERR(znode))
+					return PTR_ERR(znode);
+			}
+			nn = znode->child_cnt - 1;
+			break;
+		}
+	}
+	*zn = znode;
+	*n = nn;
+	return 0;
+}
+
+/**
+ * resolve_collision - resolve a collision.
+ * @c: UBIFS file-system description object
+ * @key: key of a directory or extended attribute entry
+ * @zn: znode is returned here
+ * @n: zbranch number is passed and returned here
+ * @nm: name of the entry
+ *
+ * This function is called for "hashed" keys to make sure that the found key
+ * really corresponds to the looked up node (directory or extended attribute
+ * entry). It returns %1 and sets @zn and @n if the collision is resolved.
+ * %0 is returned if @nm is not found and @zn and @n are set to the previous
+ * entry, i.e. to the entry after which @nm could follow if it were in TNC.
+ * This means that @n may be set to %-1 if the leftmost key in @zn is the
+ * previous one. A negative error code is returned on failures.
+ */
+static int resolve_collision(struct ubifs_info *c, const union ubifs_key *key,
+			     struct ubifs_znode **zn, int *n,
+			     const struct qstr *nm)
+{
+	int err;
+
+	err = matches_name(c, &(*zn)->zbranch[*n], nm);
+	if (unlikely(err < 0))
+		return err;
+	if (err == NAME_MATCHES)
+		return 1;
+
+	if (err == NAME_GREATER) {
+		/* Look left */
+		while (1) {
+			err = tnc_prev(c, zn, n);
+			if (err == -ENOENT) {
+				ubifs_assert(*n == 0);
+				*n = -1;
+				return 0;
+			}
+			if (err < 0)
+				return err;
+			if (keys_cmp(c, &(*zn)->zbranch[*n].key, key)) {
+				/*
+				 * We have found the branch after which we would
+				 * like to insert, but inserting in this znode
+				 * may still be wrong. Consider the following 3
+				 * znodes, in the case where we are resolving a
+				 * collision with Key2.
+				 *
+				 *                  znode zp
+				 *            ----------------------
+				 * level 1     |  Key0  |  Key1  |
+				 *            -----------------------
+				 *                 |            |
+				 *       znode za  |            |  znode zb
+				 *          ------------      ------------
+				 * level 0  |  Key0  |        |  Key2  |
+				 *          ------------      ------------
+				 *
+				 * The lookup finds Key2 in znode zb. Lets say
+				 * there is no match and the name is greater so
+				 * we look left. When we find Key0, we end up
+				 * here. If we return now, we will insert into
+				 * znode za at slot n = 1.  But that is invalid
+				 * according to the parent's keys.  Key2 must
+				 * be inserted into znode zb.
+				 *
+				 * Note, this problem is not relevant for the
+				 * case when we go right, because
+				 * 'tnc_insert()' would correct the parent key.
+				 */
+				if (*n == (*zn)->child_cnt - 1) {
+					err = tnc_next(c, zn, n);
+					if (err) {
+						/* Should be impossible */
+						ubifs_assert(0);
+						if (err == -ENOENT)
+							err = -EINVAL;
+						return err;
+					}
+					ubifs_assert(*n == 0);
+					*n = -1;
+				}
+				return 0;
+			}
+			err = matches_name(c, &(*zn)->zbranch[*n], nm);
+			if (err < 0)
+				return err;
+			if (err == NAME_LESS)
+				return 0;
+			if (err == NAME_MATCHES)
+				return 1;
+			ubifs_assert(err == NAME_GREATER);
+		}
+	} else {
+		int nn = *n;
+		struct ubifs_znode *znode = *zn;
+
+		/* Look right */
+		while (1) {
+			err = tnc_next(c, &znode, &nn);
+			if (err == -ENOENT)
+				return 0;
+			if (err < 0)
+				return err;
+			if (keys_cmp(c, &znode->zbranch[nn].key, key))
+				return 0;
+			err = matches_name(c, &znode->zbranch[nn], nm);
+			if (err < 0)
+				return err;
+			if (err == NAME_GREATER)
+				return 0;
+			*zn = znode;
+			*n = nn;
+			if (err == NAME_MATCHES)
+				return 1;
+			ubifs_assert(err == NAME_LESS);
+		}
+	}
+}
+
+/**
+ * fallible_matches_name - determine if a dent matches a given name.
+ * @c: UBIFS file-system description object
+ * @zbr: zbranch of dent
+ * @nm: name to match
+ *
+ * This is a "fallible" version of 'matches_name()' function which does not
+ * panic if the direntry/xentry referred by @zbr does not exist on the media.
+ *
+ * This function checks if xentry/direntry referred by zbranch @zbr matches name
+ * @nm. Returns %NAME_MATCHES it does, %NAME_LESS if the name referred by @zbr
+ * is less than @nm, %NAME_GREATER if it is greater than @nm, and @NOT_ON_MEDIA
+ * if xentry/direntry referred by @zbr does not exist on the media. A negative
+ * error code is returned in case of failure.
+ */
+static int fallible_matches_name(struct ubifs_info *c,
+				 struct ubifs_zbranch *zbr,
+				 const struct qstr *nm)
+{
+	struct ubifs_dent_node *dent;
+	int nlen, err;
+
+	/* If possible, match against the dent in the leaf node cache */
+	if (!zbr->leaf) {
+		dent = kmalloc(zbr->len, GFP_NOFS);
+		if (!dent)
+			return -ENOMEM;
+
+		err = fallible_read_node(c, &zbr->key, zbr, dent);
+		if (err < 0)
+			goto out_free;
+		if (err == 0) {
+			/* The node was not present */
+			err = NOT_ON_MEDIA;
+			goto out_free;
+		}
+		ubifs_assert(err == 1);
+
+		err = lnc_add_directly(c, zbr, dent);
+		if (err)
+			goto out_free;
+	} else
+		dent = zbr->leaf;
+
+	nlen = le16_to_cpu(dent->nlen);
+	err = memcmp(dent->name, nm->name, min_t(int, nlen, nm->len));
+	if (err == 0) {
+		if (nlen == nm->len)
+			return NAME_MATCHES;
+		else if (nlen < nm->len)
+			return NAME_LESS;
+		else
+			return NAME_GREATER;
+	} else if (err < 0)
+		return NAME_LESS;
+	else
+		return NAME_GREATER;
+
+out_free:
+	kfree(dent);
+	return err;
+}
+
+/**
+ * fallible_resolve_collision - resolve a collision even if nodes are missing.
+ * @c: UBIFS file-system description object
+ * @key: key
+ * @zn: znode is returned here
+ * @n: branch number is passed and returned here
+ * @nm: name of directory entry
+ * @adding: indicates caller is adding a key to the TNC
+ *
+ * This is a "fallible" version of the 'resolve_collision()' function which
+ * does not panic if one of the nodes referred to by TNC does not exist on the
+ * media. This may happen when replaying the journal if a deleted node was
+ * Garbage-collected and the commit was not done. A branch that refers to a node
+ * that is not present is called a dangling branch. The following are the return
+ * codes for this function:
+ *  o if @nm was found, %1 is returned and @zn and @n are set to the found
+ *    branch;
+ *  o if we are @adding and @nm was not found, %0 is returned;
+ *  o if we are not @adding and @nm was not found, but a dangling branch was
+ *    found, then %1 is returned and @zn and @n are set to the dangling branch;
+ *  o a negative error code is returned in case of failure.
+ */
+static int fallible_resolve_collision(struct ubifs_info *c,
+				      const union ubifs_key *key,
+				      struct ubifs_znode **zn, int *n,
+				      const struct qstr *nm, int adding)
+{
+	struct ubifs_znode *o_znode = NULL, *znode = *zn;
+	int uninitialized_var(o_n), err, cmp, unsure = 0, nn = *n;
+
+	cmp = fallible_matches_name(c, &znode->zbranch[nn], nm);
+	if (unlikely(cmp < 0))
+		return cmp;
+	if (cmp == NAME_MATCHES)
+		return 1;
+	if (cmp == NOT_ON_MEDIA) {
+		o_znode = znode;
+		o_n = nn;
+		/*
+		 * We are unlucky and hit a dangling branch straight away.
+		 * Now we do not really know where to go to find the needed
+		 * branch - to the left or to the right. Well, let's try left.
+		 */
+		unsure = 1;
+	} else if (!adding)
+		unsure = 1; /* Remove a dangling branch wherever it is */
+
+	if (cmp == NAME_GREATER || unsure) {
+		/* Look left */
+		while (1) {
+			err = tnc_prev(c, zn, n);
+			if (err == -ENOENT) {
+				ubifs_assert(*n == 0);
+				*n = -1;
+				break;
+			}
+			if (err < 0)
+				return err;
+			if (keys_cmp(c, &(*zn)->zbranch[*n].key, key)) {
+				/* See comments in 'resolve_collision()' */
+				if (*n == (*zn)->child_cnt - 1) {
+					err = tnc_next(c, zn, n);
+					if (err) {
+						/* Should be impossible */
+						ubifs_assert(0);
+						if (err == -ENOENT)
+							err = -EINVAL;
+						return err;
+					}
+					ubifs_assert(*n == 0);
+					*n = -1;
+				}
+				break;
+			}
+			err = fallible_matches_name(c, &(*zn)->zbranch[*n], nm);
+			if (err < 0)
+				return err;
+			if (err == NAME_MATCHES)
+				return 1;
+			if (err == NOT_ON_MEDIA) {
+				o_znode = *zn;
+				o_n = *n;
+				continue;
+			}
+			if (!adding)
+				continue;
+			if (err == NAME_LESS)
+				break;
+			else
+				unsure = 0;
+		}
+	}
+
+	if (cmp == NAME_LESS || unsure) {
+		/* Look right */
+		*zn = znode;
+		*n = nn;
+		while (1) {
+			err = tnc_next(c, &znode, &nn);
+			if (err == -ENOENT)
+				break;
+			if (err < 0)
+				return err;
+			if (keys_cmp(c, &znode->zbranch[nn].key, key))
+				break;
+			err = fallible_matches_name(c, &znode->zbranch[nn], nm);
+			if (err < 0)
+				return err;
+			if (err == NAME_GREATER)
+				break;
+			*zn = znode;
+			*n = nn;
+			if (err == NAME_MATCHES)
+				return 1;
+			if (err == NOT_ON_MEDIA) {
+				o_znode = znode;
+				o_n = nn;
+			}
+		}
+	}
+
+	/* Never match a dangling branch when adding */
+	if (adding || !o_znode)
+		return 0;
+
+	dbg_mnt("dangling match LEB %d:%d len %d %s",
+		o_znode->zbranch[o_n].lnum, o_znode->zbranch[o_n].offs,
+		o_znode->zbranch[o_n].len, DBGKEY(key));
+	*zn = o_znode;
+	*n = o_n;
+	return 1;
+}
+
+/**
+ * matches_position - determine if a zbranch matches a given position.
+ * @zbr: zbranch of dent
+ * @lnum: LEB number of dent to match
+ * @offs: offset of dent to match
+ *
+ * This function returns %1 if @lnum:@offs matches, and %0 otherwise.
+ */
+static int matches_position(struct ubifs_zbranch *zbr, int lnum, int offs)
+{
+	if (zbr->lnum == lnum && zbr->offs == offs)
+		return 1;
+	else
+		return 0;
+}
+
+/**
+ * resolve_collision_directly - resolve a collision directly.
+ * @c: UBIFS file-system description object
+ * @key: key of directory entry
+ * @zn: znode is passed and returned here
+ * @n: zbranch number is passed and returned here
+ * @lnum: LEB number of dent node to match
+ * @offs: offset of dent node to match
+ *
+ * This function is used for "hashed" keys to make sure the found directory or
+ * extended attribute entry node is what was looked for. It is used when the
+ * flash address of the right node is known (@lnum:@offs) which makes it much
+ * easier to resolve collisions (no need to read entries and match full
+ * names). This function returns %1 and sets @zn and @n if the collision is
+ * resolved, %0 if @lnum:@offs is not found and @zn and @n are set to the
+ * previous directory entry. Otherwise a negative error code is returned.
+ */
+static int resolve_collision_directly(struct ubifs_info *c,
+				      const union ubifs_key *key,
+				      struct ubifs_znode **zn, int *n,
+				      int lnum, int offs)
+{
+	struct ubifs_znode *znode;
+	int nn, err;
+
+	znode = *zn;
+	nn = *n;
+	if (matches_position(&znode->zbranch[nn], lnum, offs))
+		return 1;
+
+	/* Look left */
+	while (1) {
+		err = tnc_prev(c, &znode, &nn);
+		if (err == -ENOENT)
+			break;
+		if (err < 0)
+			return err;
+		if (keys_cmp(c, &znode->zbranch[nn].key, key))
+			break;
+		if (matches_position(&znode->zbranch[nn], lnum, offs)) {
+			*zn = znode;
+			*n = nn;
+			return 1;
+		}
+	}
+
+	/* Look right */
+	znode = *zn;
+	nn = *n;
+	while (1) {
+		err = tnc_next(c, &znode, &nn);
+		if (err == -ENOENT)
+			return 0;
+		if (err < 0)
+			return err;
+		if (keys_cmp(c, &znode->zbranch[nn].key, key))
+			return 0;
+		*zn = znode;
+		*n = nn;
+		if (matches_position(&znode->zbranch[nn], lnum, offs))
+			return 1;
+	}
+}
+
+/**
+ * dirty_cow_bottom_up - dirty a znode and its ancestors.
+ * @c: UBIFS file-system description object
+ * @znode: znode to dirty
+ *
+ * If we do not have a unique key that resides in a znode, then we cannot
+ * dirty that znode from the top down (i.e. by using lookup_level0_dirty)
+ * This function records the path back to the last dirty ancestor, and then
+ * dirties the znodes on that path.
+ */
+static struct ubifs_znode *dirty_cow_bottom_up(struct ubifs_info *c,
+					       struct ubifs_znode *znode)
+{
+	struct ubifs_znode *zp;
+	int *path = c->bottom_up_buf, p = 0;
+
+	ubifs_assert(c->zroot.znode);
+	ubifs_assert(znode);
+	if (c->zroot.znode->level > BOTTOM_UP_HEIGHT) {
+		kfree(c->bottom_up_buf);
+		c->bottom_up_buf = kmalloc(c->zroot.znode->level * sizeof(int),
+					   GFP_NOFS);
+		if (!c->bottom_up_buf)
+			return ERR_PTR(-ENOMEM);
+		path = c->bottom_up_buf;
+	}
+	if (c->zroot.znode->level) {
+		/* Go up until parent is dirty */
+		while (1) {
+			int n;
+
+			zp = znode->parent;
+			if (!zp)
+				break;
+			n = znode->iip;
+			ubifs_assert(p < c->zroot.znode->level);
+			path[p++] = n;
+			if (!zp->cnext && ubifs_zn_dirty(znode))
+				break;
+			znode = zp;
+		}
+	}
+
+	/* Come back down, dirtying as we go */
+	while (1) {
+		struct ubifs_zbranch *zbr;
+
+		zp = znode->parent;
+		if (zp) {
+			ubifs_assert(path[p - 1] >= 0);
+			ubifs_assert(path[p - 1] < zp->child_cnt);
+			zbr = &zp->zbranch[path[--p]];
+			znode = dirty_cow_znode(c, zbr);
+		} else {
+			ubifs_assert(znode == c->zroot.znode);
+			znode = dirty_cow_znode(c, &c->zroot);
+		}
+		if (unlikely(IS_ERR(znode)) || !p)
+			break;
+		ubifs_assert(path[p - 1] >= 0);
+		ubifs_assert(path[p - 1] < znode->child_cnt);
+		znode = znode->zbranch[path[p - 1]].znode;
+	}
+
+	return znode;
+}
+
+/**
+ * ubifs_lookup_level0 - search for zero-level znode.
+ * @c: UBIFS file-system description object
+ * @key:  key to lookup
+ * @zn: znode is returned here
+ * @n: znode branch slot number is returned here
+ *
+ * This function looks up the TNC tree and search for zero-level znode which
+ * refers key @key. The found zero-level znode is returned in @zn. There are 3
+ * cases:
+ *   o exact match, i.e. the found zero-level znode contains key @key, then %1
+ *     is returned and slot number of the matched branch is stored in @n;
+ *   o not exact match, which means that zero-level znode does not contain
+ *     @key, then %0 is returned and slot number of the closed branch is stored
+ *     in  @n;
+ *   o @key is so small that it is even less than the lowest key of the
+ *     leftmost zero-level node, then %0 is returned and %0 is stored in @n.
+ *
+ * Note, when the TNC tree is traversed, some znodes may be absent, then this
+ * function reads corresponding indexing nodes and inserts them to TNC. In
+ * case of failure, a negative error code is returned.
+ */
+int ubifs_lookup_level0(struct ubifs_info *c, const union ubifs_key *key,
+			struct ubifs_znode **zn, int *n)
+{
+	int err, exact;
+	struct ubifs_znode *znode;
+	unsigned long time = get_seconds();
+
+	dbg_tnc("search key %s", DBGKEY(key));
+
+	znode = c->zroot.znode;
+	if (unlikely(!znode)) {
+		znode = ubifs_load_znode(c, &c->zroot, NULL, 0);
+		if (IS_ERR(znode))
+			return PTR_ERR(znode);
+	}
+
+	znode->time = time;
+
+	while (1) {
+		struct ubifs_zbranch *zbr;
+
+		exact = ubifs_search_zbranch(c, znode, key, n);
+
+		if (znode->level == 0)
+			break;
+
+		if (*n < 0)
+			*n = 0;
+		zbr = &znode->zbranch[*n];
+
+		if (zbr->znode) {
+			znode->time = time;
+			znode = zbr->znode;
+			continue;
+		}
+
+		/* znode is not in TNC cache, load it from the media */
+		znode = ubifs_load_znode(c, zbr, znode, *n);
+		if (IS_ERR(znode))
+			return PTR_ERR(znode);
+	}
+
+	*zn = znode;
+	if (exact || !is_hash_key(c, key) || *n != -1) {
+		dbg_tnc("found %d, lvl %d, n %d", exact, znode->level, *n);
+		return exact;
+	}
+
+	/*
+	 * Here is a tricky place. We have not found the key and this is a
+	 * "hashed" key, which may collide. The rest of the code deals with
+	 * situations like this:
+	 *
+	 *                  | 3 | 5 |
+	 *                  /       \
+	 *          | 3 | 5 |      | 6 | 7 | (x)
+	 *
+	 * Or more a complex example:
+	 *
+	 *                | 1 | 5 |
+	 *                /       \
+	 *       | 1 | 3 |         | 5 | 8 |
+	 *              \           /
+	 *          | 5 | 5 |   | 6 | 7 | (x)
+	 *
+	 * In the examples, if we are looking for key "5", we may reach nodes
+	 * marked with "(x)". In this case what we have do is to look at the
+	 * left and see if there is "5" key there. If there is, we have to
+	 * return it.
+	 *
+	 * Note, this whole situation is possible because we allow to have
+	 * elements which are equivalent to the next key in the parent in the
+	 * children of current znode. For example, this happens if we split a
+	 * znode like this: | 3 | 5 | 5 | 6 | 7 |, which results in something
+	 * like this:
+	 *                      | 3 | 5 |
+	 *                       /     \
+	 *                | 3 | 5 |   | 5 | 6 | 7 |
+	 *                              ^
+	 * And this becomes what is at the first "picture" after key "5" marked
+	 * with "^" is removed. What could be done is we could prohibit
+	 * splitting in the middle of the colliding sequence. Also, when
+	 * removing the leftmost key, we would have to correct the key of the
+	 * parent node, which would introduce additional complications. Namely,
+	 * if we changed the the leftmost key of the parent znode, the garbage
+	 * collector would be unable to find it (GC is doing this when GC'ing
+	 * indexing LEBs). Although we already have an additional RB-tree where
+	 * we save such changed znodes (see 'ins_clr_old_idx_znode()') until
+	 * after the commit. But anyway, this does not look easy to implement
+	 * so we did not try this.
+	 */
+	err = tnc_prev(c, &znode, n);
+	if (err == -ENOENT) {
+		dbg_tnc("found 0, lvl %d, n -1", znode->level);
+		*n = -1;
+		return 0;
+	}
+	if (unlikely(err < 0))
+		return err;
+	if (keys_cmp(c, key, &znode->zbranch[*n].key)) {
+		dbg_tnc("found 0, lvl %d, n -1", znode->level);
+		*n = -1;
+		return 0;
+	}
+
+	dbg_tnc("found 1, lvl %d, n %d", znode->level, *n);
+	*zn = znode;
+	return 1;
+}
+
+/**
+ * lookup_level0_dirty - search for zero-level znode dirtying.
+ * @c: UBIFS file-system description object
+ * @key:  key to lookup
+ * @zn: znode is returned here
+ * @n: znode branch slot number is returned here
+ *
+ * This function looks up the TNC tree and search for zero-level znode which
+ * refers key @key. The found zero-level znode is returned in @zn. There are 3
+ * cases:
+ *   o exact match, i.e. the found zero-level znode contains key @key, then %1
+ *     is returned and slot number of the matched branch is stored in @n;
+ *   o not exact match, which means that zero-level znode does not contain @key
+ *     then %0 is returned and slot number of the closed branch is stored in
+ *     @n;
+ *   o @key is so small that it is even less than the lowest key of the
+ *     leftmost zero-level node, then %0 is returned and %-1 is stored in @n.
+ *
+ * Additionally all znodes in the path from the root to the located zero-level
+ * znode are marked as dirty.
+ *
+ * Note, when the TNC tree is traversed, some znodes may be absent, then this
+ * function reads corresponding indexing nodes and inserts them to TNC. In
+ * case of failure, a negative error code is returned.
+ */
+static int lookup_level0_dirty(struct ubifs_info *c, const union ubifs_key *key,
+			       struct ubifs_znode **zn, int *n)
+{
+	int err, exact;
+	struct ubifs_znode *znode;
+	unsigned long time = get_seconds();
+
+	dbg_tnc("search and dirty key %s", DBGKEY(key));
+
+	znode = c->zroot.znode;
+	if (unlikely(!znode)) {
+		znode = ubifs_load_znode(c, &c->zroot, NULL, 0);
+		if (IS_ERR(znode))
+			return PTR_ERR(znode);
+	}
+
+	znode = dirty_cow_znode(c, &c->zroot);
+	if (IS_ERR(znode))
+		return PTR_ERR(znode);
+
+	znode->time = time;
+
+	while (1) {
+		struct ubifs_zbranch *zbr;
+
+		exact = ubifs_search_zbranch(c, znode, key, n);
+
+		if (znode->level == 0)
+			break;
+
+		if (*n < 0)
+			*n = 0;
+		zbr = &znode->zbranch[*n];
+
+		if (zbr->znode) {
+			znode->time = time;
+			znode = dirty_cow_znode(c, zbr);
+			if (IS_ERR(znode))
+				return PTR_ERR(znode);
+			continue;
+		}
+
+		/* znode is not in TNC cache, load it from the media */
+		znode = ubifs_load_znode(c, zbr, znode, *n);
+		if (IS_ERR(znode))
+			return PTR_ERR(znode);
+		znode = dirty_cow_znode(c, zbr);
+		if (IS_ERR(znode))
+			return PTR_ERR(znode);
+	}
+
+	*zn = znode;
+	if (exact || !is_hash_key(c, key) || *n != -1) {
+		dbg_tnc("found %d, lvl %d, n %d", exact, znode->level, *n);
+		return exact;
+	}
+
+	/*
+	 * See huge comment at 'lookup_level0_dirty()' what is the rest of the
+	 * code.
+	 */
+	err = tnc_prev(c, &znode, n);
+	if (err == -ENOENT) {
+		*n = -1;
+		dbg_tnc("found 0, lvl %d, n -1", znode->level);
+		return 0;
+	}
+	if (unlikely(err < 0))
+		return err;
+	if (keys_cmp(c, key, &znode->zbranch[*n].key)) {
+		*n = -1;
+		dbg_tnc("found 0, lvl %d, n -1", znode->level);
+		return 0;
+	}
+
+	if (znode->cnext || !ubifs_zn_dirty(znode)) {
+		znode = dirty_cow_bottom_up(c, znode);
+		if (IS_ERR(znode))
+			return PTR_ERR(znode);
+	}
+
+	dbg_tnc("found 1, lvl %d, n %d", znode->level, *n);
+	*zn = znode;
+	return 1;
+}
+
+/**
+ * ubifs_tnc_lookup - look up a file-system node.
+ * @c: UBIFS file-system description object
+ * @key: node key to lookup
+ * @node: the node is returned here
+ *
+ * This function look up and reads node with key @key. The caller has to make
+ * sure the @node buffer is large enough to fit the node. Returns zero in case
+ * of success, %-ENOENT if the node was not found, and a negative error code in
+ * case of failure.
+ */
+int ubifs_tnc_lookup(struct ubifs_info *c, const union ubifs_key *key,
+		     void *node)
+{
+	int found, n, err;
+	struct ubifs_znode *znode;
+	struct ubifs_zbranch zbr, *zt;
+
+	mutex_lock(&c->tnc_mutex);
+	found = ubifs_lookup_level0(c, key, &znode, &n);
+	if (!found) {
+		err = -ENOENT;
+		goto out;
+	} else if (found < 0) {
+		err = found;
+		goto out;
+	}
+	zt = &znode->zbranch[n];
+	if (is_hash_key(c, key)) {
+		/*
+		 * In this case the leaf node cache gets used, so we pass the
+		 * address of the zbranch and keep the mutex locked
+		 */
+		err = tnc_read_node_nm(c, zt, node);
+		goto out;
+	}
+	zbr = znode->zbranch[n];
+	mutex_unlock(&c->tnc_mutex);
+
+	err = ubifs_tnc_read_node(c, &zbr, node);
+	return err;
+
+out:
+	mutex_unlock(&c->tnc_mutex);
+	return err;
+}
+
+/**
+ * ubifs_tnc_locate - look up a file-system node and return it and its location.
+ * @c: UBIFS file-system description object
+ * @key: node key to lookup
+ * @node: the node is returned here
+ * @lnum: LEB number is returned here
+ * @offs: offset is returned here
+ *
+ * This function is the same as 'ubifs_tnc_lookup()' but it returns the node
+ * location also. See 'ubifs_tnc_lookup()'.
+ */
+int ubifs_tnc_locate(struct ubifs_info *c, const union ubifs_key *key,
+		     void *node, int *lnum, int *offs)
+{
+	int found, n, err;
+	struct ubifs_znode *znode;
+	struct ubifs_zbranch zbr, *zt;
+
+	mutex_lock(&c->tnc_mutex);
+	found = ubifs_lookup_level0(c, key, &znode, &n);
+	if (!found) {
+		err = -ENOENT;
+		goto out;
+	} else if (found < 0) {
+		err = found;
+		goto out;
+	}
+	zt = &znode->zbranch[n];
+	if (is_hash_key(c, key)) {
+		/*
+		 * In this case the leaf node cache gets used, so we pass the
+		 * address of the zbranch and keep the mutex locked
+		 */
+		*lnum = zt->lnum;
+		*offs = zt->offs;
+		err = tnc_read_node_nm(c, zt, node);
+		goto out;
+	}
+	zbr = znode->zbranch[n];
+	mutex_unlock(&c->tnc_mutex);
+
+	*lnum = zbr.lnum;
+	*offs = zbr.offs;
+
+	err = ubifs_tnc_read_node(c, &zbr, node);
+	return err;
+
+out:
+	mutex_unlock(&c->tnc_mutex);
+	return err;
+}
+
+/**
+ * do_lookup_nm- look up a "hashed" node.
+ * @c: UBIFS file-system description object
+ * @key: node key to lookup
+ * @node: the node is returned here
+ * @nm: node name
+ *
+ * This function look up and reads a node which contains name hash in the key.
+ * Since the hash may have collisions, there may be many nodes with the same
+ * key, so we have to sequentially look to all of them until the needed one is
+ * found. This function returns zero in case of success, %-ENOENT if the node
+ * was not found, and a negative error code in case of failure.
+ */
+static int do_lookup_nm(struct ubifs_info *c, const union ubifs_key *key,
+			void *node, const struct qstr *nm)
+{
+	int found, n, err;
+	struct ubifs_znode *znode;
+	struct ubifs_zbranch zbr;
+
+	dbg_tnc("name '%.*s' key %s", nm->len, nm->name, DBGKEY(key));
+	mutex_lock(&c->tnc_mutex);
+	found = ubifs_lookup_level0(c, key, &znode, &n);
+	if (!found) {
+		err = -ENOENT;
+		goto out_unlock;
+	} else if (found < 0) {
+		err = found;
+		goto out_unlock;
+	}
+
+	ubifs_assert(n >= 0);
+
+	err = resolve_collision(c, key, &znode, &n, nm);
+	dbg_tnc("rc returned %d, znode %p, n %d", err, znode, n);
+	if (unlikely(err < 0))
+		goto out_unlock;
+	if (err == 0) {
+		err = -ENOENT;
+		goto out_unlock;
+	}
+
+	zbr = znode->zbranch[n];
+	mutex_unlock(&c->tnc_mutex);
+
+	err = tnc_read_node_nm(c, &zbr, node);
+	return err;
+
+out_unlock:
+	mutex_unlock(&c->tnc_mutex);
+	return err;
+}
+
+/**
+ * ubifs_tnc_lookup_nm - look up a "hashed" node.
+ * @c: UBIFS file-system description object
+ * @key: node key to lookup
+ * @node: the node is returned here
+ * @nm: node name
+ *
+ * This function look up and reads a node which contains name hash in the key.
+ * Since the hash may have collisions, there may be many nodes with the same
+ * key, so we have to sequentially look to all of them until the needed one is
+ * found. This function returns zero in case of success, %-ENOENT if the node
+ * was not found, and a negative error code in case of failure.
+ */
+int ubifs_tnc_lookup_nm(struct ubifs_info *c, const union ubifs_key *key,
+			void *node, const struct qstr *nm)
+{
+	int err, len;
+	const struct ubifs_dent_node *dent = node;
+
+	/*
+	 * We assume that in most of the cases there are no name collisions and
+	 * 'ubifs_tnc_lookup()' returns us the right direntry.
+	 */
+	err = ubifs_tnc_lookup(c, key, node);
+	if (err)
+		return err;
+
+	len = le16_to_cpu(dent->nlen);
+	if (nm->len == len && !memcmp(dent->name, nm->name, len))
+		return 0;
+
+	/*
+	 * Unluckily, there are hash collisions and we have to iterate over
+	 * them look at each direntry with colliding name hash sequentially.
+	 */
+	return do_lookup_nm(c, key, node, nm);
+}
+
+/**
+ * correct_parent_keys - correct parent znodes' keys.
+ * @c: UBIFS file-system description object
+ * @znode: znode to correct parent znodes for
+ *
+ * This is a helper function for 'tnc_insert()'. When the key of the leftmost
+ * zbranch changes, keys of parent znodes have to be corrected. This helper
+ * function is called in such situations and corrects the keys if needed.
+ */
+static void correct_parent_keys(const struct ubifs_info *c,
+				struct ubifs_znode *znode)
+{
+	union ubifs_key *key, *key1;
+
+	ubifs_assert(znode->parent);
+	ubifs_assert(znode->iip == 0);
+
+	key = &znode->zbranch[0].key;
+	key1 = &znode->parent->zbranch[0].key;
+
+	while (keys_cmp(c, key, key1) < 0) {
+		key_copy(c, key, key1);
+		znode = znode->parent;
+		znode->alt = 1;
+		if (!znode->parent || znode->iip)
+			break;
+		key1 = &znode->parent->zbranch[0].key;
+	}
+}
+
+/**
+ * insert_zbranch - insert a zbranch into a znode.
+ * @znode: znode into which to insert
+ * @zbr: zbranch to insert
+ * @n: slot number to insert to
+ *
+ * This is a helper function for 'tnc_insert()'. UBIFS does not allow "gaps" in
+ * znode's array of zbranches and keeps zbranches consolidated, so when a new
+ * zbranch has to be inserted to the @znode->zbranches[]' array at the @n-th
+ * slot, zbranches starting from @n have to be moved right.
+ */
+static void insert_zbranch(struct ubifs_znode *znode,
+			   const struct ubifs_zbranch *zbr, int n)
+{
+	int i;
+
+	ubifs_assert(ubifs_zn_dirty(znode));
+
+	if (znode->level) {
+		for (i = znode->child_cnt; i > n; i--) {
+			znode->zbranch[i] = znode->zbranch[i - 1];
+			if (znode->zbranch[i].znode)
+				znode->zbranch[i].znode->iip = i;
+		}
+		if (zbr->znode)
+			zbr->znode->iip = n;
+	} else
+		for (i = znode->child_cnt; i > n; i--)
+			znode->zbranch[i] = znode->zbranch[i - 1];
+
+	znode->zbranch[n] = *zbr;
+	znode->child_cnt += 1;
+
+	/*
+	 * After inserting at slot zero, the lower bound of the key range of
+	 * this znode may have changed. If this znode is subsequently split
+	 * then the upper bound of the key range may change, and furthermore
+	 * it could change to be lower than the original lower bound. If that
+	 * happens, then it will no longer be possible to find this znode in the
+	 * TNC using the key from the index node on flash. That is bad because
+	 * if it is not found, we will assume it is obsolete and may overwrite
+	 * it. Then if there is an unclean unmount, we will start using the
+	 * old index which will be broken.
+	 *
+	 * So we first mark znodes that have insertions at slot zero, and then
+	 * if they are split we add their lnum/offs to the old_idx tree.
+	 */
+	if (n == 0)
+		znode->alt = 1;
+}
+
+/**
+ * tnc_insert - insert a node into TNC.
+ * @c: UBIFS file-system description object
+ * @znode: znode to insert into
+ * @zbr: branch to insert
+ * @n: slot number to insert new zbranch to
+ *
+ * This function inserts a new node described by @zbr into znode @znode. If
+ * znode does not have a free slot for new zbranch, it is split. Parent znodes
+ * are splat as well if needed. Returns zero in case of success or a negative
+ * error code in case of failure.
+ */
+static int tnc_insert(struct ubifs_info *c, struct ubifs_znode *znode,
+		      struct ubifs_zbranch *zbr, int n)
+{
+	struct ubifs_znode *zn, *zi, *zp;
+	int i, keep, move, appending = 0;
+	union ubifs_key *key = &zbr->key;
+
+	ubifs_assert(n >= 0 && n <= c->fanout);
+
+	/* Implement naive insert for now */
+again:
+	zp = znode->parent;
+	if (znode->child_cnt < c->fanout) {
+		ubifs_assert(n != c->fanout);
+		dbg_tnc("inserted at %d level %d, key %s", n, znode->level,
+			DBGKEY(key));
+
+		insert_zbranch(znode, zbr, n);
+
+		/* Ensure parent's key is correct */
+		if (n == 0 && zp && znode->iip == 0)
+			correct_parent_keys(c, znode);
+
+		return 0;
+	}
+
+	/*
+	 * Unfortunately, @znode does not have more empty slots and we have to
+	 * split it.
+	 */
+	dbg_tnc("splitting level %d, key %s", znode->level, DBGKEY(key));
+
+	if (znode->alt)
+		/*
+		 * We can no longer be sure of finding this znode by key, so we
+		 * record it in the old_idx tree.
+		 */
+		ins_clr_old_idx_znode(c, znode);
+
+	zn = kzalloc(c->max_znode_sz, GFP_NOFS);
+	if (!zn)
+		return -ENOMEM;
+	zn->parent = zp;
+	zn->level = znode->level;
+
+	/* Decide where to split */
+	if (znode->level == 0 && n == c->fanout &&
+	    key_type(c, key) == UBIFS_DATA_KEY) {
+		union ubifs_key *key1;
+
+		/*
+		 * If this is an inode which is being appended - do not split
+		 * it because no other zbranches can be inserted between
+		 * zbranches of consecutive data nodes anyway.
+		 */
+		key1 = &znode->zbranch[n - 1].key;
+		if (key_inum(c, key1) == key_inum(c, key) &&
+		    key_type(c, key1) == UBIFS_DATA_KEY &&
+		    key_block(c, key1) == key_block(c, key) - 1)
+			appending = 1;
+	}
+
+	if (appending) {
+		keep = c->fanout;
+		move = 0;
+	} else {
+		keep = (c->fanout + 1) / 2;
+		move = c->fanout - keep;
+	}
+
+	/*
+	 * Although we don't at present, we could look at the neighbors and see
+	 * if we can move some zbranches there.
+	 */
+
+	if (n < keep) {
+		/* Insert into existing znode */
+		zi = znode;
+		move += 1;
+		keep -= 1;
+	} else {
+		/* Insert into new znode */
+		zi = zn;
+		n -= keep;
+		/* Re-parent */
+		if (zn->level != 0)
+			zbr->znode->parent = zn;
+	}
+
+	__set_bit(DIRTY_ZNODE, &zn->flags);
+	atomic_long_inc(&c->dirty_zn_cnt);
+
+	zn->child_cnt = move;
+	znode->child_cnt = keep;
+
+	dbg_tnc("moving %d, keeping %d", move, keep);
+
+	/* Move zbranch */
+	for (i = 0; i < move; i++) {
+		zn->zbranch[i] = znode->zbranch[keep + i];
+		/* Re-parent */
+		if (zn->level != 0)
+			if (zn->zbranch[i].znode) {
+				zn->zbranch[i].znode->parent = zn;
+				zn->zbranch[i].znode->iip = i;
+			}
+	}
+
+	/* Insert new key and branch */
+	dbg_tnc("inserting at %d level %d, key %s", n, zn->level, DBGKEY(key));
+
+	insert_zbranch(zi, zbr, n);
+
+	/* Insert new znode (produced by spitting) into the parent */
+	if (zp) {
+		i = n;
+		/* Locate insertion point */
+		n = znode->iip + 1;
+		if (appending && n != c->fanout)
+			appending = 0;
+
+		if (i == 0 && zi == znode && znode->iip == 0)
+			correct_parent_keys(c, znode);
+
+		/* Tail recursion */
+		zbr->key = zn->zbranch[0].key;
+		zbr->znode = zn;
+		zbr->lnum = 0;
+		zbr->offs = 0;
+		zbr->len = 0;
+		znode = zp;
+
+		goto again;
+	}
+
+	/* We have to split root znode */
+	dbg_tnc("creating new zroot at level %d", znode->level + 1);
+
+	zi = kzalloc(c->max_znode_sz, GFP_NOFS);
+	if (!zi)
+		return -ENOMEM;
+
+	zi->child_cnt = 2;
+	zi->level = znode->level + 1;
+
+	__set_bit(DIRTY_ZNODE, &zi->flags);
+	atomic_long_inc(&c->dirty_zn_cnt);
+
+	zi->zbranch[0].key = znode->zbranch[0].key;
+	zi->zbranch[0].znode = znode;
+	zi->zbranch[0].lnum = c->zroot.lnum;
+	zi->zbranch[0].offs = c->zroot.offs;
+	zi->zbranch[0].len = c->zroot.len;
+	zi->zbranch[1].key = zn->zbranch[0].key;
+	zi->zbranch[1].znode = zn;
+
+	c->zroot.lnum = 0;
+	c->zroot.offs = 0;
+	c->zroot.len = 0;
+	c->zroot.znode = zi;
+
+	zn->parent = zi;
+	zn->iip = 1;
+	znode->parent = zi;
+	znode->iip = 0;
+
+	return 0;
+}
+
+/**
+ * ubifs_tnc_add - add a node to TNC.
+ * @c: UBIFS file-system description object
+ * @key: key to add
+ * @lnum: LEB number of node
+ * @offs: node offset
+ * @len: node length
+ *
+ * This function adds a node with key @key to TNC. The node may be new or it may
+ * obsolete some existing one. Returns %0 on success or negative error code on
+ * failure.
+ */
+int ubifs_tnc_add(struct ubifs_info *c, const union ubifs_key *key, int lnum,
+		  int offs, int len)
+{
+	int found, n, err = 0;
+	struct ubifs_znode *znode;
+
+	mutex_lock(&c->tnc_mutex);
+	dbg_tnc("%d:%d, len %d, key %s", lnum, offs, len, DBGKEY(key));
+	found = lookup_level0_dirty(c, key, &znode, &n);
+	if (!found) {
+		struct ubifs_zbranch zbr;
+
+		zbr.znode = NULL;
+		zbr.lnum = lnum;
+		zbr.offs = offs;
+		zbr.len = len;
+		key_copy(c, key, &zbr.key);
+		err = tnc_insert(c, znode, &zbr, n + 1);
+	} else if (found == 1) {
+		struct ubifs_zbranch *zbr = &znode->zbranch[n];
+
+		lnc_free(zbr);
+		err = ubifs_add_dirt(c, zbr->lnum, zbr->len);
+		zbr->lnum = lnum;
+		zbr->offs = offs;
+		zbr->len = len;
+	} else
+		err = found;
+	if (!err)
+		err = dbg_check_tnc(c, 0);
+	mutex_unlock(&c->tnc_mutex);
+
+	return err;
+}
+
+/**
+ * ubifs_tnc_replace - replace a node in the TNC only if the old node is found.
+ * @c: UBIFS file-system description object
+ * @key: key to add
+ * @old_lnum: LEB number of old node
+ * @old_offs: old node offset
+ * @lnum: LEB number of node
+ * @offs: node offset
+ * @len: node length
+ *
+ * This function replaces a node with key @key in the TNC only if the old node
+ * is found.  This function is called by garbage collection when node are moved.
+ * Returns %0 on success or negative error code on failure.
+ */
+int ubifs_tnc_replace(struct ubifs_info *c, const union ubifs_key *key,
+		      int old_lnum, int old_offs, int lnum, int offs, int len)
+{
+	int found, n, err = 0;
+	struct ubifs_znode *znode;
+
+	mutex_lock(&c->tnc_mutex);
+	dbg_tnc("old LEB %d:%d, new LEB %d:%d, len %d, key %s", old_lnum,
+		old_offs, lnum, offs, len, DBGKEY(key));
+	found = lookup_level0_dirty(c, key, &znode, &n);
+	if (found < 0) {
+		err = found;
+		goto out_unlock;
+	}
+
+	if (found == 1) {
+		struct ubifs_zbranch *zbr = &znode->zbranch[n];
+
+		found = 0;
+		if (zbr->lnum == old_lnum && zbr->offs == old_offs) {
+			lnc_free(zbr);
+			err = ubifs_add_dirt(c, zbr->lnum, zbr->len);
+			if (err)
+				goto out_unlock;
+			zbr->lnum = lnum;
+			zbr->offs = offs;
+			zbr->len = len;
+			found = 1;
+		} else if (is_hash_key(c, key)) {
+			found = resolve_collision_directly(c, key, &znode, &n,
+							   old_lnum, old_offs);
+			dbg_tnc("rc returned %d, znode %p, n %d, LEB %d:%d",
+				found, znode, n, old_lnum, old_offs);
+			if (found < 0) {
+				err = found;
+				goto out_unlock;
+			}
+
+			if (found) {
+				/* Ensure the znode is dirtied */
+				if (znode->cnext || !ubifs_zn_dirty(znode)) {
+					    znode = dirty_cow_bottom_up(c,
+									znode);
+					    if (IS_ERR(znode)) {
+						    err = PTR_ERR(znode);
+						    goto out_unlock;
+					    }
+				}
+				zbr = &znode->zbranch[n];
+				lnc_free(zbr);
+				err = ubifs_add_dirt(c, zbr->lnum,
+						     zbr->len);
+				if (err)
+					goto out_unlock;
+				zbr->lnum = lnum;
+				zbr->offs = offs;
+				zbr->len = len;
+			}
+		}
+	}
+
+	if (!found)
+		err = ubifs_add_dirt(c, lnum, len);
+
+	if (!err)
+		err = dbg_check_tnc(c, 0);
+
+out_unlock:
+	mutex_unlock(&c->tnc_mutex);
+	return err;
+}
+
+/**
+ * ubifs_tnc_add_nm - add a "hashed" node to TNC.
+ * @c: UBIFS file-system description object
+ * @key: key to add
+ * @lnum: LEB number of node
+ * @offs: node offset
+ * @len: node length
+ * @nm: node name
+ *
+ * This is the same as 'ubifs_tnc_add()' but it should be used with keys which
+ * may have collisions, like directory entry keys.
+ */
+int ubifs_tnc_add_nm(struct ubifs_info *c, const union ubifs_key *key,
+		     int lnum, int offs, int len, const struct qstr *nm)
+{
+	int found, n, err = 0;
+	struct ubifs_znode *znode;
+
+	mutex_lock(&c->tnc_mutex);
+	dbg_tnc("LEB %d:%d, name '%.*s', key %s", lnum, offs, nm->len, nm->name,
+		DBGKEY(key));
+	found = lookup_level0_dirty(c, key, &znode, &n);
+	if (found < 0) {
+		err = found;
+		goto out_unlock;
+	}
+
+	if (found == 1) {
+		if (c->replaying)
+			found = fallible_resolve_collision(c, key, &znode, &n,
+							   nm, 1);
+		else
+			found = resolve_collision(c, key, &znode, &n, nm);
+		dbg_tnc("rc returned %d, znode %p, n %d", found, znode, n);
+		if (found < 0) {
+			err = found;
+			goto out_unlock;
+		}
+
+		/* Ensure the znode is dirtied */
+		if (znode->cnext || !ubifs_zn_dirty(znode)) {
+			    znode = dirty_cow_bottom_up(c, znode);
+			    if (IS_ERR(znode)) {
+				    err = PTR_ERR(znode);
+				    goto out_unlock;
+			    }
+		}
+
+		if (found == 1) {
+			struct ubifs_zbranch *zbr = &znode->zbranch[n];
+
+			lnc_free(zbr);
+			err = ubifs_add_dirt(c, zbr->lnum, zbr->len);
+			zbr->lnum = lnum;
+			zbr->offs = offs;
+			zbr->len = len;
+			goto out_unlock;
+		}
+	}
+
+	if (!found) {
+		struct ubifs_zbranch zbr;
+
+		zbr.znode = NULL;
+		zbr.lnum = lnum;
+		zbr.offs = offs;
+		zbr.len = len;
+		key_copy(c, key, &zbr.key);
+		err = tnc_insert(c, znode, &zbr, n + 1);
+		if (err)
+			goto out_unlock;
+		if (c->replaying) {
+			/*
+			 * We did not find it in the index so there may be a
+			 * dangling branch still in the index. So we remove it
+			 * by passing 'ubifs_tnc_remove_nm()' the same key but
+			 * an unmatchable name.
+			 */
+			struct qstr noname = { .len = 0, .name = "" };
+
+			err = dbg_check_tnc(c, 0);
+			mutex_unlock(&c->tnc_mutex);
+			if (err)
+				return err;
+			return ubifs_tnc_remove_nm(c, key, &noname);
+		}
+	}
+
+out_unlock:
+	if (!err)
+		err = dbg_check_tnc(c, 0);
+	mutex_unlock(&c->tnc_mutex);
+	return err;
+}
+
+/**
+ * tnc_delete - delete a znode form TNC.
+ * @c: UBIFS file-system description object
+ * @znode: znode to delete from
+ * @n: zbranch slot number to delete
+ *
+ * This function deletes a leaf node from @n-th slot of @znode. Returns zero in
+ * case of success and a negative error code in case of failure.
+ */
+static int tnc_delete(struct ubifs_info *c, struct ubifs_znode *znode, int n)
+{
+	struct ubifs_zbranch *zbr;
+	struct ubifs_znode *zp;
+	int i, err;
+
+	/* Delete without merge for now */
+	ubifs_assert(znode->level == 0);
+	ubifs_assert(n >= 0 && n < c->fanout);
+	dbg_tnc("deleting %s", DBGKEY(&znode->zbranch[n].key));
+
+	zbr = &znode->zbranch[n];
+	lnc_free(zbr);
+
+	err = ubifs_add_dirt(c, zbr->lnum, zbr->len);
+	if (err) {
+		dbg_dump_znode(c, znode);
+		return err;
+	}
+
+	/* We do not "gap" zbranch slots */
+	for (i = n; i < znode->child_cnt - 1; i++)
+		znode->zbranch[i] = znode->zbranch[i + 1];
+	znode->child_cnt -= 1;
+
+	if (znode->child_cnt > 0)
+		return 0;
+
+	/*
+	 * This was the last zbranch, we have to delete this znode from the
+	 * parent.
+	 */
+
+	do {
+		ubifs_assert(!test_bit(OBSOLETE_ZNODE, &znode->flags));
+		ubifs_assert(ubifs_zn_dirty(znode));
+
+		zp = znode->parent;
+		n = znode->iip;
+
+		atomic_long_dec(&c->dirty_zn_cnt);
+
+		err = insert_old_idx_znode(c, znode);
+		if (err)
+			return err;
+
+		if (znode->cnext) {
+			__set_bit(OBSOLETE_ZNODE, &znode->flags);
+			atomic_long_inc(&c->clean_zn_cnt);
+			atomic_long_inc(&ubifs_clean_zn_cnt);
+		} else
+			kfree(znode);
+		znode = zp;
+	} while (znode->child_cnt == 1); /* while removing last child */
+
+	/* Remove from znode, entry n - 1 */
+	znode->child_cnt -= 1;
+	ubifs_assert(znode->level != 0);
+	for (i = n; i < znode->child_cnt; i++) {
+		znode->zbranch[i] = znode->zbranch[i + 1];
+		if (znode->zbranch[i].znode)
+			znode->zbranch[i].znode->iip = i;
+	}
+
+	/*
+	 * If this is the root and it has only 1 child then
+	 * collapse the tree.
+	 */
+	if (!znode->parent) {
+		while (znode->child_cnt == 1 && znode->level != 0) {
+			zp = znode;
+			zbr = &znode->zbranch[0];
+			znode = get_znode(c, znode, 0);
+			if (IS_ERR(znode))
+				return PTR_ERR(znode);
+			znode = dirty_cow_znode(c, zbr);
+			if (IS_ERR(znode))
+				return PTR_ERR(znode);
+			znode->parent = NULL;
+			znode->iip = 0;
+			if (c->zroot.len) {
+				err = insert_old_idx(c, c->zroot.lnum,
+						     c->zroot.offs);
+				if (err)
+					return err;
+			}
+			c->zroot.lnum = zbr->lnum;
+			c->zroot.offs = zbr->offs;
+			c->zroot.len = zbr->len;
+			c->zroot.znode = znode;
+			ubifs_assert(!test_bit(OBSOLETE_ZNODE,
+				     &zp->flags));
+			ubifs_assert(test_bit(DIRTY_ZNODE, &zp->flags));
+			atomic_long_dec(&c->dirty_zn_cnt);
+
+			if (zp->cnext) {
+				__set_bit(OBSOLETE_ZNODE, &zp->flags);
+				atomic_long_inc(&c->clean_zn_cnt);
+				atomic_long_inc(&ubifs_clean_zn_cnt);
+			} else
+				kfree(zp);
+		}
+	}
+
+	return 0;
+}
+
+/**
+ * ubifs_tnc_remove - remove an index entry of a node.
+ * @c: UBIFS file-system description object
+ * @key: key of node
+ *
+ * Returns %0 on success or negative error code on failure.
+ */
+int ubifs_tnc_remove(struct ubifs_info *c, const union ubifs_key *key)
+{
+	int found, n, err = 0;
+	struct ubifs_znode *znode;
+
+	mutex_lock(&c->tnc_mutex);
+	dbg_tnc("key %s", DBGKEY(key));
+	found = lookup_level0_dirty(c, key, &znode, &n);
+	if (found < 0) {
+		err = found;
+		goto out_unlock;
+	}
+	if (found == 1)
+		err = tnc_delete(c, znode, n);
+	if (!err)
+		err = dbg_check_tnc(c, 0);
+
+out_unlock:
+	mutex_unlock(&c->tnc_mutex);
+	return err;
+}
+
+/**
+ * ubifs_tnc_remove_nm - remove an index entry for a "hashed" node.
+ * @c: UBIFS file-system description object
+ * @key: key of node
+ * @nm: directory entry name
+ *
+ * Returns %0 on success or negative error code on failure.
+ */
+int ubifs_tnc_remove_nm(struct ubifs_info *c, const union ubifs_key *key,
+			const struct qstr *nm)
+{
+	int n, err;
+	struct ubifs_znode *znode;
+
+	mutex_lock(&c->tnc_mutex);
+	dbg_tnc("%.*s, key %s", nm->len, nm->name, DBGKEY(key));
+	err = lookup_level0_dirty(c, key, &znode, &n);
+	if (err < 0)
+		goto out_unlock;
+
+	if (err) {
+		if (c->replaying)
+			err = fallible_resolve_collision(c, key, &znode, &n,
+							 nm, 0);
+		else
+			err = resolve_collision(c, key, &znode, &n, nm);
+		dbg_tnc("rc returned %d, znode %p, n %d", err, znode, n);
+		if (err < 0)
+			goto out_unlock;
+		if (err) {
+			/* Ensure the znode is dirtied */
+			if (znode->cnext || !ubifs_zn_dirty(znode)) {
+				    znode = dirty_cow_bottom_up(c, znode);
+				    if (IS_ERR(znode)) {
+					    err = PTR_ERR(znode);
+					    goto out_unlock;
+				    }
+			}
+			err = tnc_delete(c, znode, n);
+		}
+	}
+
+out_unlock:
+	if (!err)
+		err = dbg_check_tnc(c, 0);
+	mutex_unlock(&c->tnc_mutex);
+	return err;
+}
+
+/**
+ * key_in_range - determine if a key falls within a range of keys.
+ * @c: UBIFS file-system description object
+ * @key: key to check
+ * @from_key: lowest key in range
+ * @to_key: highest key in range
+ *
+ * This function returns %1 if the key is in range and %0 otherwise.
+ */
+static int key_in_range(struct ubifs_info *c, union ubifs_key *key,
+			union ubifs_key *from_key, union ubifs_key *to_key)
+{
+	if (keys_cmp(c, key, from_key) < 0)
+		return 0;
+	if (keys_cmp(c, key, to_key) > 0)
+		return 0;
+	return 1;
+}
+
+/**
+ * ubifs_tnc_remove_range - remove index entries in range.
+ * @c: UBIFS file-system description object
+ * @from_key: lowest key to remove
+ * @to_key: highest key to remove
+ *
+ * This function removes index entries starting at @from_key and ending at
+ * @to_key.  This function returns zero in case of success and a negative error
+ * code in case of failure.
+ */
+int ubifs_tnc_remove_range(struct ubifs_info *c, union ubifs_key *from_key,
+			   union ubifs_key *to_key)
+{
+	int i, n, k, err = 0;
+	struct ubifs_znode *znode;
+	union ubifs_key *key;
+
+	mutex_lock(&c->tnc_mutex);
+	while (1) {
+		/* Find first level 0 znode that contains keys to remove */
+		err = ubifs_lookup_level0(c, from_key, &znode, &n);
+		if (err < 0)
+			goto out_unlock;
+
+		if (err)
+			key = from_key;
+		else {
+			err = tnc_next(c, &znode, &n);
+			if (err == -ENOENT) {
+				err = 0;
+				goto out_unlock;
+			}
+			if (err < 0)
+				goto out_unlock;
+			key = &znode->zbranch[n].key;
+			if (!key_in_range(c, key, from_key, to_key)) {
+				err = 0;
+				goto out_unlock;
+			}
+		}
+
+		/* Ensure the znode is dirtied */
+		if (znode->cnext || !ubifs_zn_dirty(znode)) {
+			    znode = dirty_cow_bottom_up(c, znode);
+			    if (IS_ERR(znode)) {
+				    err = PTR_ERR(znode);
+				    goto out_unlock;
+			    }
+		}
+
+		/* Remove all keys in range except the first */
+		for (i = n + 1, k = 0; i < znode->child_cnt; i++, k++) {
+			key = &znode->zbranch[i].key;
+			if (!key_in_range(c, key, from_key, to_key))
+				break;
+			lnc_free(&znode->zbranch[i]);
+			err = ubifs_add_dirt(c, znode->zbranch[i].lnum,
+					     znode->zbranch[i].len);
+			if (err) {
+				dbg_dump_znode(c, znode);
+				goto out_unlock;
+			}
+			dbg_tnc("removing %s", DBGKEY(key));
+		}
+		if (k) {
+			for (i = n + 1 + k; i < znode->child_cnt; i++)
+				znode->zbranch[i - k] = znode->zbranch[i];
+			znode->child_cnt -= k;
+		}
+
+		/* Now delete the first */
+		err = tnc_delete(c, znode, n);
+		if (err)
+			goto out_unlock;
+	}
+
+out_unlock:
+	if (!err)
+		err = dbg_check_tnc(c, 0);
+	mutex_unlock(&c->tnc_mutex);
+	return err;
+}
+
+/**
+ * ubifs_tnc_remove_ino - remove an inode from TNC.
+ * @c: UBIFS file-system description object
+ * @inum: inode number to remove
+ *
+ * This function remove inode @inum and all the extended attributes associated
+ * with the anode from TNC and returns zero in case of success or a negative
+ * error code in case of failure.
+ */
+int ubifs_tnc_remove_ino(struct ubifs_info *c, ino_t inum)
+{
+	union ubifs_key key1, key2;
+	struct ubifs_dent_node *xent, *pxent = NULL;
+	struct qstr nm = { .name = NULL };
+
+	dbg_tnc("ino %lu", inum);
+
+	/*
+	 * Walk all extended attribute entries and remove them together with
+	 * corresponding extended attribute inodes.
+	 */
+	lowest_xent_key(c, &key1, inum);
+	while (1) {
+		ino_t xattr_inum;
+		int err;
+
+		xent = ubifs_tnc_next_ent(c, &key1, &nm);
+		if (IS_ERR(xent)) {
+			err = PTR_ERR(xent);
+			if (err == -ENOENT)
+				break;
+			return err;
+		}
+
+		xattr_inum = le64_to_cpu(xent->inum);
+		dbg_tnc("xent '%s', ino %lu", xent->name, xattr_inum);
+
+		nm.name = xent->name;
+		nm.len = le16_to_cpu(xent->nlen);
+		err = ubifs_tnc_remove_nm(c, &key1, &nm);
+		if (err) {
+			kfree(xent);
+			return err;
+		}
+
+		lowest_ino_key(c, &key1, xattr_inum);
+		highest_ino_key(c, &key2, xattr_inum);
+		err = ubifs_tnc_remove_range(c, &key1, &key2);
+		if (err) {
+			kfree(xent);
+			return err;
+		}
+
+		kfree(pxent);
+		pxent = xent;
+		key_read(c, &xent->key, &key1);
+	}
+
+	kfree(pxent);
+	lowest_ino_key(c, &key1, inum);
+	highest_ino_key(c, &key2, inum);
+
+	return ubifs_tnc_remove_range(c, &key1, &key2);
+}
+
+/**
+ * ubifs_tnc_next_ent - walk directory or extended attribute entries.
+ * @c: UBIFS file-system description object
+ * @key: key of last entry
+ * @nm: name of last entry found or %NULL
+ *
+ * This function finds and reads the next directory or extended attribute entry
+ * after the given key (@key) if there is one. @nm is used to resolve
+ * collisions.
+ *
+ * If the name of the current entry is not known and only the key is known,
+ * @nm->name has to be %NULL. In this case the semantics of this function is a
+ * little bit different and it returns the entry corresponding to this key, not
+ * the next one. If the key was not found, the closest "right" entry is
+ * returned.
+ *
+ * If the fist entry has to be found, @key has to contain the lowest possible
+ * key value for this inode and @name has to be %NULL.
+ *
+ * This function returns the found directory or extended attribute entry node
+ * in case of success, %-ENOENT is returned if no entry was found, and a
+ * negative error code is returned in case of failure.
+ */
+struct ubifs_dent_node *ubifs_tnc_next_ent(struct ubifs_info *c,
+					   union ubifs_key *key,
+					   const struct qstr *nm)
+{
+	int n, err, type = key_type(c, key);
+	struct ubifs_znode *znode;
+	struct ubifs_dent_node *dent;
+	struct ubifs_zbranch *zbr;
+	union ubifs_key *dkey;
+
+	dbg_tnc("%s %s", nm->name ? (char *)nm->name : "(lowest)", DBGKEY(key));
+	ubifs_assert(is_hash_key(c, key));
+
+	mutex_lock(&c->tnc_mutex);
+	err = ubifs_lookup_level0(c, key, &znode, &n);
+	if (unlikely(err < 0))
+		goto out_unlock;
+
+	if (nm->name) {
+		if (err) {
+			/* Handle collisions */
+			err = resolve_collision(c, key, &znode, &n, nm);
+			dbg_tnc("rc returned %d, znode %p, n %d",
+				err, znode, n);
+			if (unlikely(err < 0))
+				goto out_unlock;
+		}
+
+		/* Now find next entry */
+		err = tnc_next(c, &znode, &n);
+		if (unlikely(err))
+			goto out_unlock;
+	} else {
+		/*
+		 * The full name of the entry was not given, in which case the
+		 * behavior of this function is a little different and it
+		 * returns current entry, not the next one.
+		 */
+		if (!err) {
+			/*
+			 * However, the given key does not exist in the TNC
+			 * tree and @znode/@n variables contain the closest
+			 * "preceding" element. Switch to the next one.
+			 */
+			err = tnc_next(c, &znode, &n);
+			if (err)
+				goto out_unlock;
+		}
+	}
+
+	zbr = &znode->zbranch[n];
+	dent = kmalloc(zbr->len, GFP_NOFS);
+	if (unlikely(!dent)) {
+		err = -ENOMEM;
+		goto out_unlock;
+	}
+
+	/*
+	 * The above 'tnc_next()' call could lead us to the next inode, check
+	 * this.
+	 */
+	dkey = &zbr->key;
+	if (key_inum(c, dkey) != key_inum(c, key) ||
+	    key_type(c, dkey) != type) {
+		err = -ENOENT;
+		goto out_free;
+	}
+
+	err = tnc_read_node_nm(c, zbr, dent);
+	if (unlikely(err))
+		goto out_free;
+
+	mutex_unlock(&c->tnc_mutex);
+	return dent;
+
+out_free:
+	kfree(dent);
+out_unlock:
+	mutex_unlock(&c->tnc_mutex);
+	return ERR_PTR(err);
+}
+
+/**
+ * tnc_destroy_cnext - destroy left-over obsolete znodes from a failed commit.
+ * @c: UBIFS file-system description object
+ *
+ * Destroy left-over obsolete znodes from a failed commit.
+ */
+static void tnc_destroy_cnext(struct ubifs_info *c)
+{
+	struct ubifs_znode *cnext;
+
+	if (!c->cnext)
+		return;
+	ubifs_assert(c->cmt_state == COMMIT_BROKEN);
+	cnext = c->cnext;
+	do {
+		struct ubifs_znode *znode = cnext;
+
+		cnext = cnext->cnext;
+		if (test_bit(OBSOLETE_ZNODE, &znode->flags))
+			kfree(znode);
+	} while (cnext && cnext != c->cnext);
+}
+
+/**
+ * ubifs_tnc_close - close TNC subsystem and free all related resources.
+ * @c: UBIFS file-system description object
+ */
+void ubifs_tnc_close(struct ubifs_info *c)
+{
+	long clean_freed;
+
+	tnc_destroy_cnext(c);
+	if (c->zroot.znode) {
+		clean_freed = ubifs_destroy_tnc_subtree(c->zroot.znode);
+		atomic_long_sub(clean_freed, &ubifs_clean_zn_cnt);
+	}
+	kfree(c->gap_lebs);
+	kfree(c->ilebs);
+	destroy_old_idx(c);
+}
+
+/**
+ * left_znode - get the znode to the left.
+ * @c: UBIFS file-system description object
+ * @znode: znode
+ *
+ * This function returns a pointer to the znode to the left of @znode or NULL if
+ * there is not one. A negative error code is returned on failure.
+ */
+static struct ubifs_znode *left_znode(struct ubifs_info *c,
+				      struct ubifs_znode *znode)
+{
+	int level = znode->level;
+
+	while (1) {
+		int n = znode->iip - 1;
+
+		/* Go up until we can go left */
+		znode = znode->parent;
+		if (!znode)
+			return NULL;
+		if (n >= 0) {
+			/* Now go down the rightmost branch to 'level' */
+			znode = get_znode(c, znode, n);
+			if (IS_ERR(znode))
+				return znode;
+			while (znode->level != level) {
+				n = znode->child_cnt - 1;
+				znode = get_znode(c, znode, n);
+				if (IS_ERR(znode))
+					return znode;
+			}
+			break;
+		}
+	}
+	return znode;
+}
+
+/**
+ * right_znode - get the znode to the right.
+ * @c: UBIFS file-system description object
+ * @znode: znode
+ *
+ * This function returns a pointer to the znode to the right of @znode or NULL
+ * if there is not one. A negative error code is returned on failure.
+ */
+static struct ubifs_znode *right_znode(struct ubifs_info *c,
+				       struct ubifs_znode *znode)
+{
+	int level = znode->level;
+
+	while (1) {
+		int n = znode->iip + 1;
+
+		/* Go up until we can go right */
+		znode = znode->parent;
+		if (!znode)
+			return NULL;
+		if (n < znode->child_cnt) {
+			/* Now go down the leftmost branch to 'level' */
+			znode = get_znode(c, znode, n);
+			if (IS_ERR(znode))
+				return znode;
+			while (znode->level != level) {
+				znode = get_znode(c, znode, 0);
+				if (IS_ERR(znode))
+					return znode;
+			}
+			break;
+		}
+	}
+	return znode;
+}
+
+/**
+ * lookup_znode - find a particular indexing node from TNC.
+ * @c: UBIFS file-system description object
+ * @key: index node key to lookup
+ * @level: index node level
+ * @lnum: index node LEB number
+ * @offs: index node offset
+ *
+ * This function searches an indexing node by its first key @key and its
+ * address @lnum:@offs. It looks up the indexing tree by pulling all indexing
+ * nodes it traverses to TNC. This function is called fro indexing nodes which
+ * were found on the media by scanning, for example when garbage-collecting or
+ * when doing in-the-gaps commit. This means that the indexing node which is
+ * looked for does not have to have exactly the same leftmost key @key, because
+ * the leftmost key may have been changed, in which case TNC will contain a
+ * dirty znode which still refers the same @lnum:@offs. This function is clever
+ * enough to recognize such indexing nodes.
+ *
+ * Note, if a znode was deleted or changed too much, then this function will
+ * not find it. For situations like this UBIFS has the old index RB-tree
+ * (indexed by @lnum:@offs).
+ *
+ * This function returns a pointer to the znode found or %NULL if it is not
+ * found. A negative error code is returned on failure.
+ */
+static struct ubifs_znode *lookup_znode(struct ubifs_info *c,
+					union ubifs_key *key, int level,
+					int lnum, int offs)
+{
+	struct ubifs_znode *znode, *zn;
+	int n, nn;
+
+	/*
+	 * The arguments have probably been read off flash, so don't assume
+	 * they are valid.
+	 */
+	if (level < 0)
+		return ERR_PTR(-EINVAL);
+
+	/* Get the root znode */
+	znode = c->zroot.znode;
+	if (!znode) {
+		znode = ubifs_load_znode(c, &c->zroot, NULL, 0);
+		if (IS_ERR(znode))
+			return znode;
+	}
+	/* Check if it is the one we are looking for */
+	if (c->zroot.lnum == lnum && c->zroot.offs == offs)
+		return znode;
+	/* Descend to the parent level i.e. (level + 1) */
+	if (level >= znode->level)
+		return NULL;
+	while (1) {
+		ubifs_search_zbranch(c, znode, key, &n);
+		if (n < 0) {
+			/*
+			 * We reached a znode where the leftmost key is greater
+			 * than the key we are searching for. This is the same
+			 * situation as the one described in a huge comment at
+			 * the end of the 'ubifs_lookup_level0()' function. And
+			 * for exactly the same reasons we have to try to look
+			 * left before giving up.
+			 */
+			znode = left_znode(c, znode);
+			if (!znode)
+				return NULL;
+			if (IS_ERR(znode))
+				return znode;
+			ubifs_search_zbranch(c, znode, key, &n);
+			ubifs_assert(n >= 0);
+		}
+		if (znode->level == level + 1)
+			break;
+		znode = get_znode(c, znode, n);
+		if (IS_ERR(znode))
+			return znode;
+	}
+	/* Check if the child is the one we are looking for */
+	if (znode->zbranch[n].lnum == lnum && znode->zbranch[n].offs == offs)
+		return get_znode(c, znode, n);
+	/* If the key is unique, there is nowhere else to look */
+	if (!is_hash_key(c, key))
+		return NULL;
+	/*
+	 * The key is not unique and so may be also in the znodes to either
+	 * side.
+	 */
+	zn = znode;
+	nn = n;
+	/* Look left */
+	while (1) {
+		/* Move one branch to the left */
+		if (n)
+			n -= 1;
+		else {
+			znode = left_znode(c, znode);
+			if (!znode)
+				break;
+			if (IS_ERR(znode))
+				return znode;
+			n = znode->child_cnt - 1;
+		}
+		/* Check it */
+		if (znode->zbranch[n].lnum == lnum &&
+		    znode->zbranch[n].offs == offs)
+			return get_znode(c, znode, n);
+		/* Stop if the key is less than the one we are looking for */
+		if (keys_cmp(c, &znode->zbranch[n].key, key) < 0)
+			break;
+	}
+	/* Back to the middle */
+	znode = zn;
+	n = nn;
+	/* Look right */
+	while (1) {
+		/* Move one branch to the right */
+		if (++n >= znode->child_cnt) {
+			znode = right_znode(c, znode);
+			if (!znode)
+				break;
+			if (IS_ERR(znode))
+				return znode;
+			n = 0;
+		}
+		/* Check it */
+		if (znode->zbranch[n].lnum == lnum &&
+		    znode->zbranch[n].offs == offs)
+			return get_znode(c, znode, n);
+		/* Stop if the key is greater than the one we are looking for */
+		if (keys_cmp(c, &znode->zbranch[n].key, key) > 0)
+			break;
+	}
+	return NULL;
+}
+
+/**
+ * is_idx_node_in_tnc - determine if an index node is in the TNC.
+ * @c: UBIFS file-system description object
+ * @key: key of index node
+ * @level: index node level
+ * @lnum: LEB number of index node
+ * @offs: offset of index node
+ *
+ * This function returns %0 if the index node is not referred to in the TNC, %1
+ * if the index node is referred to in the TNC and the corresponding znode is
+ * dirty, %2 if an index node is referred to in the TNC and the corresponding
+ * znode is clean, and a negative error code in case of failure.
+ *
+ * Note, the @key argument has to be the key of the first child. Also note,
+ * this function relies on the fact that 0:0 is never a valid LEB number and
+ * offset for a main-area node.
+ */
+int is_idx_node_in_tnc(struct ubifs_info *c, union ubifs_key *key, int level,
+		       int lnum, int offs)
+{
+	struct ubifs_znode *znode;
+
+	znode = lookup_znode(c, key, level, lnum, offs);
+	if (!znode)
+		return 0;
+	if (IS_ERR(znode))
+		return PTR_ERR(znode);
+
+	return ubifs_zn_dirty(znode) ? 1 : 2;
+}
+
+/**
+ * is_leaf_node_in_tnc - determine if a non-indexing not is in the TNC.
+ * @c: UBIFS file-system description object
+ * @key: node key
+ * @lnum: node LEB number
+ * @offs: node offset
+ *
+ * This function returns %1 if the node is referred to in the TNC, %0 if it is
+ * not, and a negative error code in case of failure.
+ *
+ * Note, this function relies on the fact that 0:0 is never a valid LEB number
+ * and offset for a main-area node.
+ */
+static int is_leaf_node_in_tnc(struct ubifs_info *c, union ubifs_key *key,
+			       int lnum, int offs)
+{
+	struct ubifs_zbranch *zbr;
+	struct ubifs_znode *znode, *zn;
+	int n, found, err, nn;
+	const int unique = !is_hash_key(c, key);
+
+	found = ubifs_lookup_level0(c, key, &znode, &n);
+	if (found < 0)
+		return found; /* Error code */
+	if (!found)
+		return 0;
+	zbr = &znode->zbranch[n];
+	if (lnum == zbr->lnum && offs == zbr->offs)
+		return 1; /* Found it */
+	if (unique)
+		return 0;
+	/*
+	 * Because the key is not unique, we have to look left
+	 * and right as well
+	 */
+	zn = znode;
+	nn = n;
+	/* Look left */
+	while (1) {
+		err = tnc_prev(c, &znode, &n);
+		if (err == -ENOENT)
+			break;
+		if (err)
+			return err;
+		if (keys_cmp(c, key, &znode->zbranch[n].key))
+			break;
+		zbr = &znode->zbranch[n];
+		if (lnum == zbr->lnum && offs == zbr->offs)
+			return 1; /* Found it */
+	}
+	/* Look right */
+	znode = zn;
+	n = nn;
+	while (1) {
+		err = tnc_next(c, &znode, &n);
+		if (err) {
+			if (err == -ENOENT)
+				return 0;
+			return err;
+		}
+		if (keys_cmp(c, key, &znode->zbranch[n].key))
+			break;
+		zbr = &znode->zbranch[n];
+		if (lnum == zbr->lnum && offs == zbr->offs)
+			return 1; /* Found it */
+	}
+	return 0;
+}
+
+/**
+ * ubifs_tnc_has_node - determine whether a node is in the TNC.
+ * @c: UBIFS file-system description object
+ * @key: node key
+ * @level: index node level (if it is an index node)
+ * @lnum: node LEB number
+ * @offs: node offset
+ * @is_idx: non-zero if the node is an index node
+ *
+ * This function returns %1 if the node is in the TNC, %0 if it is not, and a
+ * negative error code in case of failure. For index nodes, @key has to be the
+ * key of the first child. An index node is considered to be in the TNC only if
+ * the corresponding znode is clean or has not been loaded.
+ */
+int ubifs_tnc_has_node(struct ubifs_info *c, union ubifs_key *key, int level,
+		       int lnum, int offs, int is_idx)
+{
+	int err;
+
+	mutex_lock(&c->tnc_mutex);
+	if (is_idx) {
+		err = is_idx_node_in_tnc(c, key, level, lnum, offs);
+		if (err < 0)
+			goto out_unlock;
+		if (err == 1)
+			/* The index node was found but it was dirty */
+			err = 0;
+		else if (err == 2)
+			/* The index node was found and it was clean */
+			err = 1;
+		else
+			BUG_ON(err != 0);
+	} else
+		err = is_leaf_node_in_tnc(c, key, lnum, offs);
+
+out_unlock:
+	mutex_unlock(&c->tnc_mutex);
+	return err;
+}
+
+/**
+ * ubifs_dirty_idx_node - dirty an index node.
+ * @c: UBIFS file-system description object
+ * @key: index node key
+ * @level: index node level
+ * @lnum: index node LEB number
+ * @offs: index node offset
+ *
+ * This function loads and dirties an index node so that it can be garbage
+ * collected. The @key argument has to be the key of the first child. This
+ * function relies on the fact that 0:0 is never a valid LEB number and offset
+ * for a main-area node. Returns %0 on success and a negative error code on
+ * failure.
+ */
+int ubifs_dirty_idx_node(struct ubifs_info *c, union ubifs_key *key, int level,
+			 int lnum, int offs)
+{
+	struct ubifs_znode *znode;
+	int err = 0;
+
+	mutex_lock(&c->tnc_mutex);
+	znode = lookup_znode(c, key, level, lnum, offs);
+	if (!znode)
+		goto out_unlock;
+	if (IS_ERR(znode)) {
+		err = PTR_ERR(znode);
+		goto out_unlock;
+	}
+	znode = dirty_cow_bottom_up(c, znode);
+	if (IS_ERR(znode)) {
+		err = PTR_ERR(znode);
+		goto out_unlock;
+	}
+
+out_unlock:
+	mutex_unlock(&c->tnc_mutex);
+	return err;
+}
diff --git a/fs/ubifs/tnc_commit.c b/fs/ubifs/tnc_commit.c
new file mode 100644
index 00000000000..8117e65ba2e
--- /dev/null
+++ b/fs/ubifs/tnc_commit.c
@@ -0,0 +1,1103 @@
+/*
+ * This file is part of UBIFS.
+ *
+ * Copyright (C) 2006-2008 Nokia Corporation.
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 as published by
+ * the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
+ * more details.
+ *
+ * You should have received a copy of the GNU General Public License along with
+ * this program; if not, write to the Free Software Foundation, Inc., 51
+ * Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
+ *
+ * Authors: Adrian Hunter
+ *          Artem Bityutskiy (Битюцкий Артём)
+ */
+
+/* This file implements TNC functions for committing */
+
+#include "ubifs.h"
+
+/**
+ * make_idx_node - make an index node for fill-the-gaps method of TNC commit.
+ * @c: UBIFS file-system description object
+ * @idx: buffer in which to place new index node
+ * @znode: znode from which to make new index node
+ * @lnum: LEB number where new index node will be written
+ * @offs: offset where new index node will be written
+ * @len: length of new index node
+ */
+static int make_idx_node(struct ubifs_info *c, struct ubifs_idx_node *idx,
+			 struct ubifs_znode *znode, int lnum, int offs, int len)
+{
+	struct ubifs_znode *zp;
+	int i, err;
+
+	/* Make index node */
+	idx->ch.node_type = UBIFS_IDX_NODE;
+	idx->child_cnt = cpu_to_le16(znode->child_cnt);
+	idx->level = cpu_to_le16(znode->level);
+	for (i = 0; i < znode->child_cnt; i++) {
+		struct ubifs_branch *br = ubifs_idx_branch(c, idx, i);
+		struct ubifs_zbranch *zbr = &znode->zbranch[i];
+
+		key_write_idx(c, &zbr->key, &br->key);
+		br->lnum = cpu_to_le32(zbr->lnum);
+		br->offs = cpu_to_le32(zbr->offs);
+		br->len = cpu_to_le32(zbr->len);
+		if (!zbr->lnum || !zbr->len) {
+			ubifs_err("bad ref in znode");
+			dbg_dump_znode(c, znode);
+			if (zbr->znode)
+				dbg_dump_znode(c, zbr->znode);
+		}
+	}
+	ubifs_prepare_node(c, idx, len, 0);
+
+#ifdef CONFIG_UBIFS_FS_DEBUG
+	znode->lnum = lnum;
+	znode->offs = offs;
+	znode->len = len;
+#endif
+
+	err = insert_old_idx_znode(c, znode);
+
+	/* Update the parent */
+	zp = znode->parent;
+	if (zp) {
+		struct ubifs_zbranch *zbr;
+
+		zbr = &zp->zbranch[znode->iip];
+		zbr->lnum = lnum;
+		zbr->offs = offs;
+		zbr->len = len;
+	} else {
+		c->zroot.lnum = lnum;
+		c->zroot.offs = offs;
+		c->zroot.len = len;
+	}
+	c->calc_idx_sz += ALIGN(len, 8);
+
+	atomic_long_dec(&c->dirty_zn_cnt);
+
+	ubifs_assert(ubifs_zn_dirty(znode));
+	ubifs_assert(test_bit(COW_ZNODE, &znode->flags));
+
+	__clear_bit(DIRTY_ZNODE, &znode->flags);
+	__clear_bit(COW_ZNODE, &znode->flags);
+
+	return err;
+}
+
+/**
+ * fill_gap - make index nodes in gaps in dirty index LEBs.
+ * @c: UBIFS file-system description object
+ * @lnum: LEB number that gap appears in
+ * @gap_start: offset of start of gap
+ * @gap_end: offset of end of gap
+ * @dirt: adds dirty space to this
+ *
+ * This function returns the number of index nodes written into the gap.
+ */
+static int fill_gap(struct ubifs_info *c, int lnum, int gap_start, int gap_end,
+		    int *dirt)
+{
+	int len, gap_remains, gap_pos, written, pad_len;
+
+	ubifs_assert((gap_start & 7) == 0);
+	ubifs_assert((gap_end & 7) == 0);
+	ubifs_assert(gap_end >= gap_start);
+
+	gap_remains = gap_end - gap_start;
+	if (!gap_remains)
+		return 0;
+	gap_pos = gap_start;
+	written = 0;
+	while (c->enext) {
+		len = ubifs_idx_node_sz(c, c->enext->child_cnt);
+		if (len < gap_remains) {
+			struct ubifs_znode *znode = c->enext;
+			const int alen = ALIGN(len, 8);
+			int err;
+
+			ubifs_assert(alen <= gap_remains);
+			err = make_idx_node(c, c->ileb_buf + gap_pos, znode,
+					    lnum, gap_pos, len);
+			if (err)
+				return err;
+			gap_remains -= alen;
+			gap_pos += alen;
+			c->enext = znode->cnext;
+			if (c->enext == c->cnext)
+				c->enext = NULL;
+			written += 1;
+		} else
+			break;
+	}
+	if (gap_end == c->leb_size) {
+		c->ileb_len = ALIGN(gap_pos, c->min_io_size);
+		/* Pad to end of min_io_size */
+		pad_len = c->ileb_len - gap_pos;
+	} else
+		/* Pad to end of gap */
+		pad_len = gap_remains;
+	dbg_gc("LEB %d:%d to %d len %d nodes written %d wasted bytes %d",
+	       lnum, gap_start, gap_end, gap_end - gap_start, written, pad_len);
+	ubifs_pad(c, c->ileb_buf + gap_pos, pad_len);
+	*dirt += pad_len;
+	return written;
+}
+
+/**
+ * find_old_idx - find an index node obsoleted since the last commit start.
+ * @c: UBIFS file-system description object
+ * @lnum: LEB number of obsoleted index node
+ * @offs: offset of obsoleted index node
+ *
+ * Returns %1 if found and %0 otherwise.
+ */
+static int find_old_idx(struct ubifs_info *c, int lnum, int offs)
+{
+	struct ubifs_old_idx *o;
+	struct rb_node *p;
+
+	p = c->old_idx.rb_node;
+	while (p) {
+		o = rb_entry(p, struct ubifs_old_idx, rb);
+		if (lnum < o->lnum)
+			p = p->rb_left;
+		else if (lnum > o->lnum)
+			p = p->rb_right;
+		else if (offs < o->offs)
+			p = p->rb_left;
+		else if (offs > o->offs)
+			p = p->rb_right;
+		else
+			return 1;
+	}
+	return 0;
+}
+
+/**
+ * is_idx_node_in_use - determine if an index node can be overwritten.
+ * @c: UBIFS file-system description object
+ * @key: key of index node
+ * @level: index node level
+ * @lnum: LEB number of index node
+ * @offs: offset of index node
+ *
+ * If @key / @lnum / @offs identify an index node that was not part of the old
+ * index, then this function returns %0 (obsolete).  Else if the index node was
+ * part of the old index but is now dirty %1 is returned, else if it is clean %2
+ * is returned. A negative error code is returned on failure.
+ */
+static int is_idx_node_in_use(struct ubifs_info *c, union ubifs_key *key,
+			      int level, int lnum, int offs)
+{
+	int ret;
+
+	ret = is_idx_node_in_tnc(c, key, level, lnum, offs);
+	if (ret < 0)
+		return ret; /* Error code */
+	if (ret == 0)
+		if (find_old_idx(c, lnum, offs))
+			return 1;
+	return ret;
+}
+
+/**
+ * layout_leb_in_gaps - layout index nodes using in-the-gaps method.
+ * @c: UBIFS file-system description object
+ * @p: return LEB number here
+ *
+ * This function lays out new index nodes for dirty znodes using in-the-gaps
+ * method of TNC commit.
+ * This function merely puts the next znode into the next gap, making no attempt
+ * to try to maximise the number of znodes that fit.
+ * This function returns the number of index nodes written into the gaps, or a
+ * negative error code on failure.
+ */
+static int layout_leb_in_gaps(struct ubifs_info *c, int *p)
+{
+	struct ubifs_scan_leb *sleb;
+	struct ubifs_scan_node *snod;
+	int lnum, dirt = 0, gap_start, gap_end, err, written, tot_written;
+
+	tot_written = 0;
+	/* Get an index LEB with lots of obsolete index nodes */
+	lnum = ubifs_find_dirty_idx_leb(c);
+	if (lnum < 0)
+		/*
+		 * There also may be dirt in the index head that could be
+		 * filled, however we do not check there at present.
+		 */
+		return lnum; /* Error code */
+	*p = lnum;
+	dbg_gc("LEB %d", lnum);
+	/*
+	 * Scan the index LEB.  We use the generic scan for this even though
+	 * it is more comprehensive and less efficient than is needed for this
+	 * purpose.
+	 */
+	sleb = ubifs_scan(c, lnum, 0, c->ileb_buf);
+	c->ileb_len = 0;
+	if (IS_ERR(sleb))
+		return PTR_ERR(sleb);
+	gap_start = 0;
+	list_for_each_entry(snod, &sleb->nodes, list) {
+		struct ubifs_idx_node *idx;
+		int in_use, level;
+
+		ubifs_assert(snod->type == UBIFS_IDX_NODE);
+		idx = snod->node;
+		key_read(c, ubifs_idx_key(c, idx), &snod->key);
+		level = le16_to_cpu(idx->level);
+		/* Determine if the index node is in use (not obsolete) */
+		in_use = is_idx_node_in_use(c, &snod->key, level, lnum,
+					    snod->offs);
+		if (in_use < 0) {
+			ubifs_scan_destroy(sleb);
+			return in_use; /* Error code */
+		}
+		if (in_use) {
+			if (in_use == 1)
+				dirt += ALIGN(snod->len, 8);
+			/*
+			 * The obsolete index nodes form gaps that can be
+			 * overwritten.  This gap has ended because we have
+			 * found an index node that is still in use
+			 * i.e. not obsolete
+			 */
+			gap_end = snod->offs;
+			/* Try to fill gap */
+			written = fill_gap(c, lnum, gap_start, gap_end, &dirt);
+			if (written < 0) {
+				ubifs_scan_destroy(sleb);
+				return written; /* Error code */
+			}
+			tot_written += written;
+			gap_start = ALIGN(snod->offs + snod->len, 8);
+		}
+	}
+	ubifs_scan_destroy(sleb);
+	c->ileb_len = c->leb_size;
+	gap_end = c->leb_size;
+	/* Try to fill gap */
+	written = fill_gap(c, lnum, gap_start, gap_end, &dirt);
+	if (written < 0)
+		return written; /* Error code */
+	tot_written += written;
+	if (tot_written == 0) {
+		struct ubifs_lprops lp;
+
+		dbg_gc("LEB %d wrote %d index nodes", lnum, tot_written);
+		err = ubifs_read_one_lp(c, lnum, &lp);
+		if (err)
+			return err;
+		if (lp.free == c->leb_size) {
+			/*
+			 * We must have snatched this LEB from the idx_gc list
+			 * so we need to correct the free and dirty space.
+			 */
+			err = ubifs_change_one_lp(c, lnum,
+						  c->leb_size - c->ileb_len,
+						  dirt, 0, 0, 0);
+			if (err)
+				return err;
+		}
+		return 0;
+	}
+	err = ubifs_change_one_lp(c, lnum, c->leb_size - c->ileb_len, dirt,
+				  0, 0, 0);
+	if (err)
+		return err;
+	err = ubifs_leb_change(c, lnum, c->ileb_buf, c->ileb_len,
+			       UBI_SHORTTERM);
+	if (err)
+		return err;
+	dbg_gc("LEB %d wrote %d index nodes", lnum, tot_written);
+	return tot_written;
+}
+
+/**
+ * get_leb_cnt - calculate the number of empty LEBs needed to commit.
+ * @c: UBIFS file-system description object
+ * @cnt: number of znodes to commit
+ *
+ * This function returns the number of empty LEBs needed to commit @cnt znodes
+ * to the current index head.  The number is not exact and may be more than
+ * needed.
+ */
+static int get_leb_cnt(struct ubifs_info *c, int cnt)
+{
+	int d;
+
+	/* Assume maximum index node size (i.e. overestimate space needed) */
+	cnt -= (c->leb_size - c->ihead_offs) / c->max_idx_node_sz;
+	if (cnt < 0)
+		cnt = 0;
+	d = c->leb_size / c->max_idx_node_sz;
+	return DIV_ROUND_UP(cnt, d);
+}
+
+/**
+ * layout_in_gaps - in-the-gaps method of committing TNC.
+ * @c: UBIFS file-system description object
+ * @cnt: number of dirty znodes to commit.
+ *
+ * This function lays out new index nodes for dirty znodes using in-the-gaps
+ * method of TNC commit.
+ *
+ * This function returns %0 on success and a negative error code on failure.
+ */
+static int layout_in_gaps(struct ubifs_info *c, int cnt)
+{
+	int err, leb_needed_cnt, written, *p;
+
+	dbg_gc("%d znodes to write", cnt);
+
+	c->gap_lebs = kmalloc(sizeof(int) * (c->lst.idx_lebs + 1), GFP_NOFS);
+	if (!c->gap_lebs)
+		return -ENOMEM;
+
+	p = c->gap_lebs;
+	do {
+		ubifs_assert(p < c->gap_lebs + sizeof(int) * c->lst.idx_lebs);
+		written = layout_leb_in_gaps(c, p);
+		if (written < 0) {
+			err = written;
+			if (err == -ENOSPC) {
+				if (!dbg_force_in_the_gaps_enabled) {
+					/*
+					 * Do not print scary warnings if the
+					 * debugging option which forces
+					 * in-the-gaps is enabled.
+					 */
+					ubifs_err("out of space");
+					spin_lock(&c->space_lock);
+					dbg_dump_budg(c);
+					spin_unlock(&c->space_lock);
+					dbg_dump_lprops(c);
+				}
+				/* Try to commit anyway */
+				err = 0;
+				break;
+			}
+			kfree(c->gap_lebs);
+			c->gap_lebs = NULL;
+			return err;
+		}
+		p++;
+		cnt -= written;
+		leb_needed_cnt = get_leb_cnt(c, cnt);
+		dbg_gc("%d znodes remaining, need %d LEBs, have %d", cnt,
+		       leb_needed_cnt, c->ileb_cnt);
+	} while (leb_needed_cnt > c->ileb_cnt);
+
+	*p = -1;
+	return 0;
+}
+
+/**
+ * layout_in_empty_space - layout index nodes in empty space.
+ * @c: UBIFS file-system description object
+ *
+ * This function lays out new index nodes for dirty znodes using empty LEBs.
+ *
+ * This function returns %0 on success and a negative error code on failure.
+ */
+static int layout_in_empty_space(struct ubifs_info *c)
+{
+	struct ubifs_znode *znode, *cnext, *zp;
+	int lnum, offs, len, next_len, buf_len, buf_offs, used, avail;
+	int wlen, blen, err;
+
+	cnext = c->enext;
+	if (!cnext)
+		return 0;
+
+	lnum = c->ihead_lnum;
+	buf_offs = c->ihead_offs;
+
+	buf_len = ubifs_idx_node_sz(c, c->fanout);
+	buf_len = ALIGN(buf_len, c->min_io_size);
+	used = 0;
+	avail = buf_len;
+
+	/* Ensure there is enough room for first write */
+	next_len = ubifs_idx_node_sz(c, cnext->child_cnt);
+	if (buf_offs + next_len > c->leb_size)
+		lnum = -1;
+
+	while (1) {
+		znode = cnext;
+
+		len = ubifs_idx_node_sz(c, znode->child_cnt);
+
+		/* Determine the index node position */
+		if (lnum == -1) {
+			if (c->ileb_nxt >= c->ileb_cnt) {
+				ubifs_err("out of space");
+				return -ENOSPC;
+			}
+			lnum = c->ilebs[c->ileb_nxt++];
+			buf_offs = 0;
+			used = 0;
+			avail = buf_len;
+		}
+
+		offs = buf_offs + used;
+
+#ifdef CONFIG_UBIFS_FS_DEBUG
+		znode->lnum = lnum;
+		znode->offs = offs;
+		znode->len = len;
+#endif
+
+		/* Update the parent */
+		zp = znode->parent;
+		if (zp) {
+			struct ubifs_zbranch *zbr;
+			int i;
+
+			i = znode->iip;
+			zbr = &zp->zbranch[i];
+			zbr->lnum = lnum;
+			zbr->offs = offs;
+			zbr->len = len;
+		} else {
+			c->zroot.lnum = lnum;
+			c->zroot.offs = offs;
+			c->zroot.len = len;
+		}
+		c->calc_idx_sz += ALIGN(len, 8);
+
+		/*
+		 * Once lprops is updated, we can decrease the dirty znode count
+		 * but it is easier to just do it here.
+		 */
+		atomic_long_dec(&c->dirty_zn_cnt);
+
+		/*
+		 * Calculate the next index node length to see if there is
+		 * enough room for it
+		 */
+		cnext = znode->cnext;
+		if (cnext == c->cnext)
+			next_len = 0;
+		else
+			next_len = ubifs_idx_node_sz(c, cnext->child_cnt);
+
+		if (c->min_io_size == 1) {
+			buf_offs += ALIGN(len, 8);
+			if (next_len) {
+				if (buf_offs + next_len <= c->leb_size)
+					continue;
+				err = ubifs_update_one_lp(c, lnum, 0,
+						c->leb_size - buf_offs, 0, 0);
+				if (err)
+					return err;
+				lnum = -1;
+				continue;
+			}
+			err = ubifs_update_one_lp(c, lnum,
+					c->leb_size - buf_offs, 0, 0, 0);
+			if (err)
+				return err;
+			break;
+		}
+
+		/* Update buffer positions */
+		wlen = used + len;
+		used += ALIGN(len, 8);
+		avail -= ALIGN(len, 8);
+
+		if (next_len != 0 &&
+		    buf_offs + used + next_len <= c->leb_size &&
+		    avail > 0)
+			continue;
+
+		if (avail <= 0 && next_len &&
+		    buf_offs + used + next_len <= c->leb_size)
+			blen = buf_len;
+		else
+			blen = ALIGN(wlen, c->min_io_size);
+
+		/* The buffer is full or there are no more znodes to do */
+		buf_offs += blen;
+		if (next_len) {
+			if (buf_offs + next_len > c->leb_size) {
+				err = ubifs_update_one_lp(c, lnum,
+					c->leb_size - buf_offs, blen - used,
+					0, 0);
+				if (err)
+					return err;
+				lnum = -1;
+			}
+			used -= blen;
+			if (used < 0)
+				used = 0;
+			avail = buf_len - used;
+			continue;
+		}
+		err = ubifs_update_one_lp(c, lnum, c->leb_size - buf_offs,
+					  blen - used, 0, 0);
+		if (err)
+			return err;
+		break;
+	}
+
+#ifdef CONFIG_UBIFS_FS_DEBUG
+	c->new_ihead_lnum = lnum;
+	c->new_ihead_offs = buf_offs;
+#endif
+
+	return 0;
+}
+
+/**
+ * layout_commit - determine positions of index nodes to commit.
+ * @c: UBIFS file-system description object
+ * @no_space: indicates that insufficient empty LEBs were allocated
+ * @cnt: number of znodes to commit
+ *
+ * Calculate and update the positions of index nodes to commit.  If there were
+ * an insufficient number of empty LEBs allocated, then index nodes are placed
+ * into the gaps created by obsolete index nodes in non-empty index LEBs.  For
+ * this purpose, an obsolete index node is one that was not in the index as at
+ * the end of the last commit.  To write "in-the-gaps" requires that those index
+ * LEBs are updated atomically in-place.
+ */
+static int layout_commit(struct ubifs_info *c, int no_space, int cnt)
+{
+	int err;
+
+	if (no_space) {
+		err = layout_in_gaps(c, cnt);
+		if (err)
+			return err;
+	}
+	err = layout_in_empty_space(c);
+	return err;
+}
+
+/**
+ * find_first_dirty - find first dirty znode.
+ * @znode: znode to begin searching from
+ */
+static struct ubifs_znode *find_first_dirty(struct ubifs_znode *znode)
+{
+	int i, cont;
+
+	if (!znode)
+		return NULL;
+
+	while (1) {
+		if (znode->level == 0) {
+			if (ubifs_zn_dirty(znode))
+				return znode;
+			return NULL;
+		}
+		cont = 0;
+		for (i = 0; i < znode->child_cnt; i++) {
+			struct ubifs_zbranch *zbr = &znode->zbranch[i];
+
+			if (zbr->znode && ubifs_zn_dirty(zbr->znode)) {
+				znode = zbr->znode;
+				cont = 1;
+				break;
+			}
+		}
+		if (!cont) {
+			if (ubifs_zn_dirty(znode))
+				return znode;
+			return NULL;
+		}
+	}
+}
+
+/**
+ * find_next_dirty - find next dirty znode.
+ * @znode: znode to begin searching from
+ */
+static struct ubifs_znode *find_next_dirty(struct ubifs_znode *znode)
+{
+	int n = znode->iip + 1;
+
+	znode = znode->parent;
+	if (!znode)
+		return NULL;
+	for (; n < znode->child_cnt; n++) {
+		struct ubifs_zbranch *zbr = &znode->zbranch[n];
+
+		if (zbr->znode && ubifs_zn_dirty(zbr->znode))
+			return find_first_dirty(zbr->znode);
+	}
+	return znode;
+}
+
+/**
+ * get_znodes_to_commit - create list of dirty znodes to commit.
+ * @c: UBIFS file-system description object
+ *
+ * This function returns the number of znodes to commit.
+ */
+static int get_znodes_to_commit(struct ubifs_info *c)
+{
+	struct ubifs_znode *znode, *cnext;
+	int cnt = 0;
+
+	c->cnext = find_first_dirty(c->zroot.znode);
+	znode = c->enext = c->cnext;
+	if (!znode) {
+		dbg_cmt("no znodes to commit");
+		return 0;
+	}
+	cnt += 1;
+	while (1) {
+		ubifs_assert(!test_bit(COW_ZNODE, &znode->flags));
+		__set_bit(COW_ZNODE, &znode->flags);
+		znode->alt = 0;
+		cnext = find_next_dirty(znode);
+		if (!cnext) {
+			znode->cnext = c->cnext;
+			break;
+		}
+		znode->cnext = cnext;
+		znode = cnext;
+		cnt += 1;
+	}
+	dbg_cmt("committing %d znodes", cnt);
+	ubifs_assert(cnt == atomic_long_read(&c->dirty_zn_cnt));
+	return cnt;
+}
+
+/**
+ * alloc_idx_lebs - allocate empty LEBs to be used to commit.
+ * @c: UBIFS file-system description object
+ * @cnt: number of znodes to commit
+ *
+ * This function returns %-ENOSPC if it cannot allocate a sufficient number of
+ * empty LEBs.  %0 is returned on success, otherwise a negative error code
+ * is returned.
+ */
+static int alloc_idx_lebs(struct ubifs_info *c, int cnt)
+{
+	int i, leb_cnt, lnum;
+
+	c->ileb_cnt = 0;
+	c->ileb_nxt = 0;
+	leb_cnt = get_leb_cnt(c, cnt);
+	dbg_cmt("need about %d empty LEBS for TNC commit", leb_cnt);
+	if (!leb_cnt)
+		return 0;
+	c->ilebs = kmalloc(leb_cnt * sizeof(int), GFP_NOFS);
+	if (!c->ilebs)
+		return -ENOMEM;
+	for (i = 0; i < leb_cnt; i++) {
+		lnum = ubifs_find_free_leb_for_idx(c);
+		if (lnum < 0)
+			return lnum;
+		c->ilebs[c->ileb_cnt++] = lnum;
+		dbg_cmt("LEB %d", lnum);
+	}
+	if (dbg_force_in_the_gaps())
+		return -ENOSPC;
+	return 0;
+}
+
+/**
+ * free_unused_idx_lebs - free unused LEBs that were allocated for the commit.
+ * @c: UBIFS file-system description object
+ *
+ * It is possible that we allocate more empty LEBs for the commit than we need.
+ * This functions frees the surplus.
+ *
+ * This function returns %0 on success and a negative error code on failure.
+ */
+static int free_unused_idx_lebs(struct ubifs_info *c)
+{
+	int i, err = 0, lnum, er;
+
+	for (i = c->ileb_nxt; i < c->ileb_cnt; i++) {
+		lnum = c->ilebs[i];
+		dbg_cmt("LEB %d", lnum);
+		er = ubifs_change_one_lp(c, lnum, LPROPS_NC, LPROPS_NC, 0,
+					 LPROPS_INDEX | LPROPS_TAKEN, 0);
+		if (!err)
+			err = er;
+	}
+	return err;
+}
+
+/**
+ * free_idx_lebs - free unused LEBs after commit end.
+ * @c: UBIFS file-system description object
+ *
+ * This function returns %0 on success and a negative error code on failure.
+ */
+static int free_idx_lebs(struct ubifs_info *c)
+{
+	int err;
+
+	err = free_unused_idx_lebs(c);
+	kfree(c->ilebs);
+	c->ilebs = NULL;
+	return err;
+}
+
+/**
+ * ubifs_tnc_start_commit - start TNC commit.
+ * @c: UBIFS file-system description object
+ * @zroot: new index root position is returned here
+ *
+ * This function prepares the list of indexing nodes to commit and lays out
+ * their positions on flash. If there is not enough free space it uses the
+ * in-gap commit method. Returns zero in case of success and a negative error
+ * code in case of failure.
+ */
+int ubifs_tnc_start_commit(struct ubifs_info *c, struct ubifs_zbranch *zroot)
+{
+	int err = 0, cnt;
+
+	mutex_lock(&c->tnc_mutex);
+	err = dbg_check_tnc(c, 1);
+	if (err)
+		goto out;
+	cnt = get_znodes_to_commit(c);
+	if (cnt != 0) {
+		int no_space = 0;
+
+		err = alloc_idx_lebs(c, cnt);
+		if (err == -ENOSPC)
+			no_space = 1;
+		else if (err)
+			goto out_free;
+		err = layout_commit(c, no_space, cnt);
+		if (err)
+			goto out_free;
+		ubifs_assert(atomic_long_read(&c->dirty_zn_cnt) == 0);
+		err = free_unused_idx_lebs(c);
+		if (err)
+			goto out;
+	}
+	destroy_old_idx(c);
+	memcpy(zroot, &c->zroot, sizeof(struct ubifs_zbranch));
+
+	err = ubifs_save_dirty_idx_lnums(c);
+	if (err)
+		goto out;
+
+	spin_lock(&c->space_lock);
+	/*
+	 * Although we have not finished committing yet, update size of the
+	 * committed index ('c->old_idx_sz') and zero out the index growth
+	 * budget. It is OK to do this now, because we've reserved all the
+	 * space which is needed to commit the index, and it is save for the
+	 * budgeting subsystem to assume the index is already committed,
+	 * even though it is not.
+	 */
+	c->old_idx_sz = c->calc_idx_sz;
+	c->budg_uncommitted_idx = 0;
+	spin_unlock(&c->space_lock);
+	mutex_unlock(&c->tnc_mutex);
+
+	dbg_cmt("number of index LEBs %d", c->lst.idx_lebs);
+	dbg_cmt("size of index %llu", c->calc_idx_sz);
+	return err;
+
+out_free:
+	free_idx_lebs(c);
+out:
+	mutex_unlock(&c->tnc_mutex);
+	return err;
+}
+
+/**
+ * write_index - write index nodes.
+ * @c: UBIFS file-system description object
+ *
+ * This function writes the index nodes whose positions were laid out in the
+ * layout_in_empty_space function.
+ */
+static int write_index(struct ubifs_info *c)
+{
+	struct ubifs_idx_node *idx;
+	struct ubifs_znode *znode, *cnext;
+	int i, lnum, offs, len, next_len, buf_len, buf_offs, used;
+	int avail, wlen, err, lnum_pos = 0;
+
+	cnext = c->enext;
+	if (!cnext)
+		return 0;
+
+	/*
+	 * Always write index nodes to the index head so that index nodes and
+	 * other types of nodes are never mixed in the same erase block.
+	 */
+	lnum = c->ihead_lnum;
+	buf_offs = c->ihead_offs;
+
+	/* Allocate commit buffer */
+	buf_len = ALIGN(c->max_idx_node_sz, c->min_io_size);
+	used = 0;
+	avail = buf_len;
+
+	/* Ensure there is enough room for first write */
+	next_len = ubifs_idx_node_sz(c, cnext->child_cnt);
+	if (buf_offs + next_len > c->leb_size) {
+		err = ubifs_update_one_lp(c, lnum, LPROPS_NC, 0, 0,
+					  LPROPS_TAKEN);
+		if (err)
+			return err;
+		lnum = -1;
+	}
+
+	while (1) {
+		cond_resched();
+
+		znode = cnext;
+		idx = c->cbuf + used;
+
+		/* Make index node */
+		idx->ch.node_type = UBIFS_IDX_NODE;
+		idx->child_cnt = cpu_to_le16(znode->child_cnt);
+		idx->level = cpu_to_le16(znode->level);
+		for (i = 0; i < znode->child_cnt; i++) {
+			struct ubifs_branch *br = ubifs_idx_branch(c, idx, i);
+			struct ubifs_zbranch *zbr = &znode->zbranch[i];
+
+			key_write_idx(c, &zbr->key, &br->key);
+			br->lnum = cpu_to_le32(zbr->lnum);
+			br->offs = cpu_to_le32(zbr->offs);
+			br->len = cpu_to_le32(zbr->len);
+			if (!zbr->lnum || !zbr->len) {
+				ubifs_err("bad ref in znode");
+				dbg_dump_znode(c, znode);
+				if (zbr->znode)
+					dbg_dump_znode(c, zbr->znode);
+			}
+		}
+		len = ubifs_idx_node_sz(c, znode->child_cnt);
+		ubifs_prepare_node(c, idx, len, 0);
+
+		/* Determine the index node position */
+		if (lnum == -1) {
+			lnum = c->ilebs[lnum_pos++];
+			buf_offs = 0;
+			used = 0;
+			avail = buf_len;
+		}
+		offs = buf_offs + used;
+
+#ifdef CONFIG_UBIFS_FS_DEBUG
+		if (lnum != znode->lnum || offs != znode->offs ||
+		    len != znode->len) {
+			ubifs_err("inconsistent znode posn");
+			return -EINVAL;
+		}
+#endif
+
+		/* Grab some stuff from znode while we still can */
+		cnext = znode->cnext;
+
+		ubifs_assert(ubifs_zn_dirty(znode));
+		ubifs_assert(test_bit(COW_ZNODE, &znode->flags));
+
+		/*
+		 * It is important that other threads should see %DIRTY_ZNODE
+		 * flag cleared before %COW_ZNODE. Specifically, it matters in
+		 * the 'dirty_cow_znode()' function. This is the reason for the
+		 * first barrier. Also, we want the bit changes to be seen to
+		 * other threads ASAP, to avoid unnecesarry copying, which is
+		 * the reason for the second barrier.
+		 */
+		clear_bit(DIRTY_ZNODE, &znode->flags);
+		smp_mb__before_clear_bit();
+		clear_bit(COW_ZNODE, &znode->flags);
+		smp_mb__after_clear_bit();
+
+		/* Do not access znode from this point on */
+
+		/* Update buffer positions */
+		wlen = used + len;
+		used += ALIGN(len, 8);
+		avail -= ALIGN(len, 8);
+
+		/*
+		 * Calculate the next index node length to see if there is
+		 * enough room for it
+		 */
+		if (cnext == c->cnext)
+			next_len = 0;
+		else
+			next_len = ubifs_idx_node_sz(c, cnext->child_cnt);
+
+		if (c->min_io_size == 1) {
+			/*
+			 * Write the prepared index node immediately if there is
+			 * no minimum IO size
+			 */
+			err = ubifs_leb_write(c, lnum, c->cbuf, buf_offs,
+					      wlen, UBI_SHORTTERM);
+			if (err)
+				return err;
+			buf_offs += ALIGN(wlen, 8);
+			if (next_len) {
+				used = 0;
+				avail = buf_len;
+				if (buf_offs + next_len > c->leb_size) {
+					err = ubifs_update_one_lp(c, lnum,
+						LPROPS_NC, 0, 0, LPROPS_TAKEN);
+					if (err)
+						return err;
+					lnum = -1;
+				}
+				continue;
+			}
+		} else {
+			int blen, nxt_offs = buf_offs + used + next_len;
+
+			if (next_len && nxt_offs <= c->leb_size) {
+				if (avail > 0)
+					continue;
+				else
+					blen = buf_len;
+			} else {
+				wlen = ALIGN(wlen, 8);
+				blen = ALIGN(wlen, c->min_io_size);
+				ubifs_pad(c, c->cbuf + wlen, blen - wlen);
+			}
+			/*
+			 * The buffer is full or there are no more znodes
+			 * to do
+			 */
+			err = ubifs_leb_write(c, lnum, c->cbuf, buf_offs,
+					      blen, UBI_SHORTTERM);
+			if (err)
+				return err;
+			buf_offs += blen;
+			if (next_len) {
+				if (nxt_offs > c->leb_size) {
+					err = ubifs_update_one_lp(c, lnum,
+						LPROPS_NC, 0, 0, LPROPS_TAKEN);
+					if (err)
+						return err;
+					lnum = -1;
+				}
+				used -= blen;
+				if (used < 0)
+					used = 0;
+				avail = buf_len - used;
+				memmove(c->cbuf, c->cbuf + blen, used);
+				continue;
+			}
+		}
+		break;
+	}
+
+#ifdef CONFIG_UBIFS_FS_DEBUG
+	if (lnum != c->new_ihead_lnum || buf_offs != c->new_ihead_offs) {
+		ubifs_err("inconsistent ihead");
+		return -EINVAL;
+	}
+#endif
+
+	c->ihead_lnum = lnum;
+	c->ihead_offs = buf_offs;
+
+	return 0;
+}
+
+/**
+ * free_obsolete_znodes - free obsolete znodes.
+ * @c: UBIFS file-system description object
+ *
+ * At the end of commit end, obsolete znodes are freed.
+ */
+static void free_obsolete_znodes(struct ubifs_info *c)
+{
+	struct ubifs_znode *znode, *cnext;
+
+	cnext = c->cnext;
+	do {
+		znode = cnext;
+		cnext = znode->cnext;
+		if (test_bit(OBSOLETE_ZNODE, &znode->flags))
+			kfree(znode);
+		else {
+			znode->cnext = NULL;
+			atomic_long_inc(&c->clean_zn_cnt);
+			atomic_long_inc(&ubifs_clean_zn_cnt);
+		}
+	} while (cnext != c->cnext);
+}
+
+/**
+ * return_gap_lebs - return LEBs used by the in-gap commit method.
+ * @c: UBIFS file-system description object
+ *
+ * This function clears the "taken" flag for the LEBs which were used by the
+ * "commit in-the-gaps" method.
+ */
+static int return_gap_lebs(struct ubifs_info *c)
+{
+	int *p, err;
+
+	if (!c->gap_lebs)
+		return 0;
+
+	dbg_cmt("");
+	for (p = c->gap_lebs; *p != -1; p++) {
+		err = ubifs_change_one_lp(c, *p, LPROPS_NC, LPROPS_NC, 0,
+					  LPROPS_TAKEN, 0);
+		if (err)
+			return err;
+	}
+
+	kfree(c->gap_lebs);
+	c->gap_lebs = NULL;
+	return 0;
+}
+
+/**
+ * ubifs_tnc_end_commit - update the TNC for commit end.
+ * @c: UBIFS file-system description object
+ *
+ * Write the dirty znodes.
+ */
+int ubifs_tnc_end_commit(struct ubifs_info *c)
+{
+	int err;
+
+	if (!c->cnext)
+		return 0;
+
+	err = return_gap_lebs(c);
+	if (err)
+		return err;
+
+	err = write_index(c);
+	if (err)
+		return err;
+
+	mutex_lock(&c->tnc_mutex);
+
+	dbg_cmt("TNC height is %d", c->zroot.znode->level + 1);
+
+	free_obsolete_znodes(c);
+
+	c->cnext = NULL;
+	kfree(c->ilebs);
+	c->ilebs = NULL;
+
+	mutex_unlock(&c->tnc_mutex);
+
+	return 0;
+}
diff --git a/fs/ubifs/tnc_misc.c b/fs/ubifs/tnc_misc.c
new file mode 100644
index 00000000000..a25c1cc1f8d
--- /dev/null
+++ b/fs/ubifs/tnc_misc.c
@@ -0,0 +1,494 @@
+/*
+ * This file is part of UBIFS.
+ *
+ * Copyright (C) 2006-2008 Nokia Corporation.
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 as published by
+ * the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
+ * more details.
+ *
+ * You should have received a copy of the GNU General Public License along with
+ * this program; if not, write to the Free Software Foundation, Inc., 51
+ * Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
+ *
+ * Authors: Adrian Hunter
+ *          Artem Bityutskiy (Битюцкий Артём)
+ */
+
+/*
+ * This file contains miscelanious TNC-related functions shared betweend
+ * different files. This file does not form any logically separate TNC
+ * sub-system. The file was created because there is a lot of TNC code and
+ * putting it all in one file would make that file too big and unreadable.
+ */
+
+#include "ubifs.h"
+
+/**
+ * ubifs_tnc_levelorder_next - next TNC tree element in levelorder traversal.
+ * @zr: root of the subtree to traverse
+ * @znode: previous znode
+ *
+ * This function implements levelorder TNC traversal. The LNC is ignored.
+ * Returns the next element or %NULL if @znode is already the last one.
+ */
+struct ubifs_znode *ubifs_tnc_levelorder_next(struct ubifs_znode *zr,
+					      struct ubifs_znode *znode)
+{
+	int level, iip, level_search = 0;
+	struct ubifs_znode *zn;
+
+	ubifs_assert(zr);
+
+	if (unlikely(!znode))
+		return zr;
+
+	if (unlikely(znode == zr)) {
+		if (znode->level == 0)
+			return NULL;
+		return ubifs_tnc_find_child(zr, 0);
+	}
+
+	level = znode->level;
+
+	iip = znode->iip;
+	while (1) {
+		ubifs_assert(znode->level <= zr->level);
+
+		/*
+		 * First walk up until there is a znode with next branch to
+		 * look at.
+		 */
+		while (znode->parent != zr && iip >= znode->parent->child_cnt) {
+			znode = znode->parent;
+			iip = znode->iip;
+		}
+
+		if (unlikely(znode->parent == zr &&
+			     iip >= znode->parent->child_cnt)) {
+			/* This level is done, switch to the lower one */
+			level -= 1;
+			if (level_search || level < 0)
+				/*
+				 * We were already looking for znode at lower
+				 * level ('level_search'). As we are here
+				 * again, it just does not exist. Or all levels
+				 * were finished ('level < 0').
+				 */
+				return NULL;
+
+			level_search = 1;
+			iip = -1;
+			znode = ubifs_tnc_find_child(zr, 0);
+			ubifs_assert(znode);
+		}
+
+		/* Switch to the next index */
+		zn = ubifs_tnc_find_child(znode->parent, iip + 1);
+		if (!zn) {
+			/* No more children to look at, we have walk up */
+			iip = znode->parent->child_cnt;
+			continue;
+		}
+
+		/* Walk back down to the level we came from ('level') */
+		while (zn->level != level) {
+			znode = zn;
+			zn = ubifs_tnc_find_child(zn, 0);
+			if (!zn) {
+				/*
+				 * This path is not too deep so it does not
+				 * reach 'level'. Try next path.
+				 */
+				iip = znode->iip;
+				break;
+			}
+		}
+
+		if (zn) {
+			ubifs_assert(zn->level >= 0);
+			return zn;
+		}
+	}
+}
+
+/**
+ * ubifs_search_zbranch - search znode branch.
+ * @c: UBIFS file-system description object
+ * @znode: znode to search in
+ * @key: key to search for
+ * @n: znode branch slot number is returned here
+ *
+ * This is a helper function which search branch with key @key in @znode using
+ * binary search. The result of the search may be:
+ *   o exact match, then %1 is returned, and the slot number of the branch is
+ *     stored in @n;
+ *   o no exact match, then %0 is returned and the slot number of the left
+ *     closest branch is returned in @n; the slot if all keys in this znode are
+ *     greater than @key, then %-1 is returned in @n.
+ */
+int ubifs_search_zbranch(const struct ubifs_info *c,
+			 const struct ubifs_znode *znode,
+			 const union ubifs_key *key, int *n)
+{
+	int beg = 0, end = znode->child_cnt, uninitialized_var(mid);
+	int uninitialized_var(cmp);
+	const struct ubifs_zbranch *zbr = &znode->zbranch[0];
+
+	ubifs_assert(end > beg);
+
+	while (end > beg) {
+		mid = (beg + end) >> 1;
+		cmp = keys_cmp(c, key, &zbr[mid].key);
+		if (cmp > 0)
+			beg = mid + 1;
+		else if (cmp < 0)
+			end = mid;
+		else {
+			*n = mid;
+			return 1;
+		}
+	}
+
+	*n = end - 1;
+
+	/* The insert point is after *n */
+	ubifs_assert(*n >= -1 && *n < znode->child_cnt);
+	if (*n == -1)
+		ubifs_assert(keys_cmp(c, key, &zbr[0].key) < 0);
+	else
+		ubifs_assert(keys_cmp(c, key, &zbr[*n].key) > 0);
+	if (*n + 1 < znode->child_cnt)
+		ubifs_assert(keys_cmp(c, key, &zbr[*n + 1].key) < 0);
+
+	return 0;
+}
+
+/**
+ * ubifs_tnc_postorder_first - find first znode to do postorder tree traversal.
+ * @znode: znode to start at (root of the sub-tree to traverse)
+ *
+ * Find the lowest leftmost znode in a subtree of the TNC tree. The LNC is
+ * ignored.
+ */
+struct ubifs_znode *ubifs_tnc_postorder_first(struct ubifs_znode *znode)
+{
+	if (unlikely(!znode))
+		return NULL;
+
+	while (znode->level > 0) {
+		struct ubifs_znode *child;
+
+		child = ubifs_tnc_find_child(znode, 0);
+		if (!child)
+			return znode;
+		znode = child;
+	}
+
+	return znode;
+}
+
+/**
+ * ubifs_tnc_postorder_next - next TNC tree element in postorder traversal.
+ * @znode: previous znode
+ *
+ * This function implements postorder TNC traversal. The LNC is ignored.
+ * Returns the next element or %NULL if @znode is already the last one.
+ */
+struct ubifs_znode *ubifs_tnc_postorder_next(struct ubifs_znode *znode)
+{
+	struct ubifs_znode *zn;
+
+	ubifs_assert(znode);
+	if (unlikely(!znode->parent))
+		return NULL;
+
+	/* Switch to the next index in the parent */
+	zn = ubifs_tnc_find_child(znode->parent, znode->iip + 1);
+	if (!zn)
+		/* This is in fact the last child, return parent */
+		return znode->parent;
+
+	/* Go to the first znode in this new subtree */
+	return ubifs_tnc_postorder_first(zn);
+}
+
+/**
+ * ubifs_destroy_tnc_subtree - destroy all znodes connected to a subtree.
+ * @znode: znode defining subtree to destroy
+ *
+ * This function destroys subtree of the TNC tree. Returns number of clean
+ * znodes in the subtree.
+ */
+long ubifs_destroy_tnc_subtree(struct ubifs_znode *znode)
+{
+	struct ubifs_znode *zn = ubifs_tnc_postorder_first(znode);
+	long clean_freed = 0;
+	int n;
+
+	ubifs_assert(zn);
+	while (1) {
+		for (n = 0; n < zn->child_cnt; n++) {
+			if (!zn->zbranch[n].znode)
+				continue;
+
+			if (zn->level > 0 &&
+			    !ubifs_zn_dirty(zn->zbranch[n].znode))
+				clean_freed += 1;
+
+			cond_resched();
+			kfree(zn->zbranch[n].znode);
+		}
+
+		if (zn == znode) {
+			if (!ubifs_zn_dirty(zn))
+				clean_freed += 1;
+			kfree(zn);
+			return clean_freed;
+		}
+
+		zn = ubifs_tnc_postorder_next(zn);
+	}
+}
+
+/**
+ * read_znode - read an indexing node from flash and fill znode.
+ * @c: UBIFS file-system description object
+ * @lnum: LEB of the indexing node to read
+ * @offs: node offset
+ * @len: node length
+ * @znode: znode to read to
+ *
+ * This function reads an indexing node from the flash media and fills znode
+ * with the read data. Returns zero in case of success and a negative error
+ * code in case of failure. The read indexing node is validated and if anything
+ * is wrong with it, this function prints complaint messages and returns
+ * %-EINVAL.
+ */
+static int read_znode(struct ubifs_info *c, int lnum, int offs, int len,
+		      struct ubifs_znode *znode)
+{
+	int i, err, type, cmp;
+	struct ubifs_idx_node *idx;
+
+	idx = kmalloc(c->max_idx_node_sz, GFP_NOFS);
+	if (!idx)
+		return -ENOMEM;
+
+	err = ubifs_read_node(c, idx, UBIFS_IDX_NODE, len, lnum, offs);
+	if (err < 0) {
+		kfree(idx);
+		return err;
+	}
+
+	znode->child_cnt = le16_to_cpu(idx->child_cnt);
+	znode->level = le16_to_cpu(idx->level);
+
+	dbg_tnc("LEB %d:%d, level %d, %d branch",
+		lnum, offs, znode->level, znode->child_cnt);
+
+	if (znode->child_cnt > c->fanout || znode->level > UBIFS_MAX_LEVELS) {
+		dbg_err("current fanout %d, branch count %d",
+			c->fanout, znode->child_cnt);
+		dbg_err("max levels %d, znode level %d",
+			UBIFS_MAX_LEVELS, znode->level);
+		err = 1;
+		goto out_dump;
+	}
+
+	for (i = 0; i < znode->child_cnt; i++) {
+		const struct ubifs_branch *br = ubifs_idx_branch(c, idx, i);
+		struct ubifs_zbranch *zbr = &znode->zbranch[i];
+
+		key_read(c, &br->key, &zbr->key);
+		zbr->lnum = le32_to_cpu(br->lnum);
+		zbr->offs = le32_to_cpu(br->offs);
+		zbr->len  = le32_to_cpu(br->len);
+		zbr->znode = NULL;
+
+		/* Validate branch */
+
+		if (zbr->lnum < c->main_first ||
+		    zbr->lnum >= c->leb_cnt || zbr->offs < 0 ||
+		    zbr->offs + zbr->len > c->leb_size || zbr->offs & 7) {
+			dbg_err("bad branch %d", i);
+			err = 2;
+			goto out_dump;
+		}
+
+		switch (key_type(c, &zbr->key)) {
+		case UBIFS_INO_KEY:
+		case UBIFS_DATA_KEY:
+		case UBIFS_DENT_KEY:
+		case UBIFS_XENT_KEY:
+			break;
+		default:
+			dbg_msg("bad key type at slot %d: %s", i,
+				DBGKEY(&zbr->key));
+			err = 3;
+			goto out_dump;
+		}
+
+		if (znode->level)
+			continue;
+
+		type = key_type(c, &zbr->key);
+		if (c->ranges[type].max_len == 0) {
+			if (zbr->len != c->ranges[type].len) {
+				dbg_err("bad target node (type %d) length (%d)",
+					type, zbr->len);
+				dbg_err("have to be %d", c->ranges[type].len);
+				err = 4;
+				goto out_dump;
+			}
+		} else if (zbr->len < c->ranges[type].min_len ||
+			   zbr->len > c->ranges[type].max_len) {
+			dbg_err("bad target node (type %d) length (%d)",
+				type, zbr->len);
+			dbg_err("have to be in range of %d-%d",
+				c->ranges[type].min_len,
+				c->ranges[type].max_len);
+			err = 5;
+			goto out_dump;
+		}
+	}
+
+	/*
+	 * Ensure that the next key is greater or equivalent to the
+	 * previous one.
+	 */
+	for (i = 0; i < znode->child_cnt - 1; i++) {
+		const union ubifs_key *key1, *key2;
+
+		key1 = &znode->zbranch[i].key;
+		key2 = &znode->zbranch[i + 1].key;
+
+		cmp = keys_cmp(c, key1, key2);
+		if (cmp > 0) {
+			dbg_err("bad key order (keys %d and %d)", i, i + 1);
+			err = 6;
+			goto out_dump;
+		} else if (cmp == 0 && !is_hash_key(c, key1)) {
+			/* These can only be keys with colliding hash */
+			dbg_err("keys %d and %d are not hashed but equivalent",
+				i, i + 1);
+			err = 7;
+			goto out_dump;
+		}
+	}
+
+	kfree(idx);
+	return 0;
+
+out_dump:
+	ubifs_err("bad indexing node at LEB %d:%d, error %d", lnum, offs, err);
+	dbg_dump_node(c, idx);
+	kfree(idx);
+	return -EINVAL;
+}
+
+/**
+ * ubifs_load_znode - load znode to TNC cache.
+ * @c: UBIFS file-system description object
+ * @zbr: znode branch
+ * @parent: znode's parent
+ * @iip: index in parent
+ *
+ * This function loads znode pointed to by @zbr into the TNC cache and
+ * returns pointer to it in case of success and a negative error code in case
+ * of failure.
+ */
+struct ubifs_znode *ubifs_load_znode(struct ubifs_info *c,
+				     struct ubifs_zbranch *zbr,
+				     struct ubifs_znode *parent, int iip)
+{
+	int err;
+	struct ubifs_znode *znode;
+
+	ubifs_assert(!zbr->znode);
+	/*
+	 * A slab cache is not presently used for znodes because the znode size
+	 * depends on the fanout which is stored in the superblock.
+	 */
+	znode = kzalloc(c->max_znode_sz, GFP_NOFS);
+	if (!znode)
+		return ERR_PTR(-ENOMEM);
+
+	err = read_znode(c, zbr->lnum, zbr->offs, zbr->len, znode);
+	if (err)
+		goto out;
+
+	atomic_long_inc(&c->clean_zn_cnt);
+
+	/*
+	 * Increment the global clean znode counter as well. It is OK that
+	 * global and per-FS clean znode counters may be inconsistent for some
+	 * short time (because we might be preempted at this point), the global
+	 * one is only used in shrinker.
+	 */
+	atomic_long_inc(&ubifs_clean_zn_cnt);
+
+	zbr->znode = znode;
+	znode->parent = parent;
+	znode->time = get_seconds();
+	znode->iip = iip;
+
+	return znode;
+
+out:
+	kfree(znode);
+	return ERR_PTR(err);
+}
+
+/**
+ * ubifs_tnc_read_node - read a leaf node from the flash media.
+ * @c: UBIFS file-system description object
+ * @zbr: key and position of the node
+ * @node: node is returned here
+ *
+ * This function reads a node defined by @zbr from the flash media. Returns
+ * zero in case of success or a negative negative error code in case of
+ * failure.
+ */
+int ubifs_tnc_read_node(struct ubifs_info *c, struct ubifs_zbranch *zbr,
+			void *node)
+{
+	union ubifs_key key1, *key = &zbr->key;
+	int err, type = key_type(c, key);
+	struct ubifs_wbuf *wbuf;
+
+	/*
+	 * 'zbr' has to point to on-flash node. The node may sit in a bud and
+	 * may even be in a write buffer, so we have to take care about this.
+	 */
+	wbuf = ubifs_get_wbuf(c, zbr->lnum);
+	if (wbuf)
+		err = ubifs_read_node_wbuf(wbuf, node, type, zbr->len,
+					   zbr->lnum, zbr->offs);
+	else
+		err = ubifs_read_node(c, node, type, zbr->len, zbr->lnum,
+				      zbr->offs);
+
+	if (err) {
+		dbg_tnc("key %s", DBGKEY(key));
+		return err;
+	}
+
+	/* Make sure the key of the read node is correct */
+	key_read(c, key, &key1);
+	if (memcmp(node + UBIFS_KEY_OFFSET, &key1, c->key_len)) {
+		ubifs_err("bad key in node at LEB %d:%d",
+			  zbr->lnum, zbr->offs);
+		dbg_tnc("looked for key %s found node's key %s",
+			DBGKEY(key), DBGKEY1(&key1));
+		dbg_dump_node(c, node);
+		return -EINVAL;
+	}
+
+	return 0;
+}
diff --git a/fs/ubifs/ubifs-media.h b/fs/ubifs/ubifs-media.h
new file mode 100644
index 00000000000..0cc7da9bed4
--- /dev/null
+++ b/fs/ubifs/ubifs-media.h
@@ -0,0 +1,745 @@
+/*
+ * This file is part of UBIFS.
+ *
+ * Copyright (C) 2006-2008 Nokia Corporation.
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 as published by
+ * the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
+ * more details.
+ *
+ * You should have received a copy of the GNU General Public License along with
+ * this program; if not, write to the Free Software Foundation, Inc., 51
+ * Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
+ *
+ * Authors: Artem Bityutskiy (Битюцкий Артём)
+ *          Adrian Hunter
+ */
+
+/*
+ * This file describes UBIFS on-flash format and contains definitions of all the
+ * relevant data structures and constants.
+ *
+ * All UBIFS on-flash objects are stored in the form of nodes. All nodes start
+ * with the UBIFS node magic number and have the same common header. Nodes
+ * always sit at 8-byte aligned positions on the media and node header sizes are
+ * also 8-byte aligned (except for the indexing node and the padding node).
+ */
+
+#ifndef __UBIFS_MEDIA_H__
+#define __UBIFS_MEDIA_H__
+
+/* UBIFS node magic number (must not have the padding byte first or last) */
+#define UBIFS_NODE_MAGIC  0x06101831
+
+/* UBIFS on-flash format version */
+#define UBIFS_FORMAT_VERSION 4
+
+/* Minimum logical eraseblock size in bytes */
+#define UBIFS_MIN_LEB_SZ (15*1024)
+
+/* Initial CRC32 value used when calculating CRC checksums */
+#define UBIFS_CRC32_INIT 0xFFFFFFFFU
+
+/*
+ * UBIFS does not try to compress data if its length is less than the below
+ * constant.
+ */
+#define UBIFS_MIN_COMPR_LEN 128
+
+/* Root inode number */
+#define UBIFS_ROOT_INO 1
+
+/* Lowest inode number used for regular inodes (not UBIFS-only internal ones) */
+#define UBIFS_FIRST_INO 64
+
+/*
+ * Maximum file name and extended attribute length (must be a multiple of 8,
+ * minus 1).
+ */
+#define UBIFS_MAX_NLEN 255
+
+/* Maximum number of data journal heads */
+#define UBIFS_MAX_JHEADS 1
+
+/*
+ * Size of UBIFS data block. Note, UBIFS is not a block oriented file-system,
+ * which means that it does not treat the underlying media as consisting of
+ * blocks like in case of hard drives. Do not be confused. UBIFS block is just
+ * the maximum amount of data which one data node can have or which can be
+ * attached to an inode node.
+ */
+#define UBIFS_BLOCK_SIZE  4096
+#define UBIFS_BLOCK_SHIFT 12
+#define UBIFS_BLOCK_MASK  0x00000FFF
+
+/* UBIFS padding byte pattern (must not be first or last byte of node magic) */
+#define UBIFS_PADDING_BYTE 0xCE
+
+/* Maximum possible key length */
+#define UBIFS_MAX_KEY_LEN 16
+
+/* Key length ("simple" format) */
+#define UBIFS_SK_LEN 8
+
+/* Minimum index tree fanout */
+#define UBIFS_MIN_FANOUT 2
+
+/* Maximum number of levels in UBIFS indexing B-tree */
+#define UBIFS_MAX_LEVELS 512
+
+/* Maximum amount of data attached to an inode in bytes */
+#define UBIFS_MAX_INO_DATA UBIFS_BLOCK_SIZE
+
+/* LEB Properties Tree fanout (must be power of 2) and fanout shift */
+#define UBIFS_LPT_FANOUT 4
+#define UBIFS_LPT_FANOUT_SHIFT 2
+
+/* LEB Properties Tree bit field sizes */
+#define UBIFS_LPT_CRC_BITS 16
+#define UBIFS_LPT_CRC_BYTES 2
+#define UBIFS_LPT_TYPE_BITS 4
+
+/* The key is always at the same position in all keyed nodes */
+#define UBIFS_KEY_OFFSET offsetof(struct ubifs_ino_node, key)
+
+/*
+ * LEB Properties Tree node types.
+ *
+ * UBIFS_LPT_PNODE: LPT leaf node (contains LEB properties)
+ * UBIFS_LPT_NNODE: LPT internal node
+ * UBIFS_LPT_LTAB: LPT's own lprops table
+ * UBIFS_LPT_LSAVE: LPT's save table (big model only)
+ * UBIFS_LPT_NODE_CNT: count of LPT node types
+ * UBIFS_LPT_NOT_A_NODE: all ones (15 for 4 bits) is never a valid node type
+ */
+enum {
+	UBIFS_LPT_PNODE,
+	UBIFS_LPT_NNODE,
+	UBIFS_LPT_LTAB,
+	UBIFS_LPT_LSAVE,
+	UBIFS_LPT_NODE_CNT,
+	UBIFS_LPT_NOT_A_NODE = (1 << UBIFS_LPT_TYPE_BITS) - 1,
+};
+
+/*
+ * UBIFS inode types.
+ *
+ * UBIFS_ITYPE_REG: regular file
+ * UBIFS_ITYPE_DIR: directory
+ * UBIFS_ITYPE_LNK: soft link
+ * UBIFS_ITYPE_BLK: block device node
+ * UBIFS_ITYPE_CHR: character device node
+ * UBIFS_ITYPE_FIFO: fifo
+ * UBIFS_ITYPE_SOCK: socket
+ * UBIFS_ITYPES_CNT: count of supported file types
+ */
+enum {
+	UBIFS_ITYPE_REG,
+	UBIFS_ITYPE_DIR,
+	UBIFS_ITYPE_LNK,
+	UBIFS_ITYPE_BLK,
+	UBIFS_ITYPE_CHR,
+	UBIFS_ITYPE_FIFO,
+	UBIFS_ITYPE_SOCK,
+	UBIFS_ITYPES_CNT,
+};
+
+/*
+ * Supported key hash functions.
+ *
+ * UBIFS_KEY_HASH_R5: R5 hash
+ * UBIFS_KEY_HASH_TEST: test hash which just returns first 4 bytes of the name
+ */
+enum {
+	UBIFS_KEY_HASH_R5,
+	UBIFS_KEY_HASH_TEST,
+};
+
+/*
+ * Supported key formats.
+ *
+ * UBIFS_SIMPLE_KEY_FMT: simple key format
+ */
+enum {
+	UBIFS_SIMPLE_KEY_FMT,
+};
+
+/*
+ * The simple key format uses 29 bits for storing UBIFS block number and hash
+ * value.
+ */
+#define UBIFS_S_KEY_BLOCK_BITS 29
+#define UBIFS_S_KEY_BLOCK_MASK 0x1FFFFFFF
+#define UBIFS_S_KEY_HASH_BITS  UBIFS_S_KEY_BLOCK_BITS
+#define UBIFS_S_KEY_HASH_MASK  UBIFS_S_KEY_BLOCK_MASK
+
+/*
+ * Key types.
+ *
+ * UBIFS_INO_KEY: inode node key
+ * UBIFS_DATA_KEY: data node key
+ * UBIFS_DENT_KEY: directory entry node key
+ * UBIFS_XENT_KEY: extended attribute entry key
+ * UBIFS_KEY_TYPES_CNT: number of supported key types
+ */
+enum {
+	UBIFS_INO_KEY,
+	UBIFS_DATA_KEY,
+	UBIFS_DENT_KEY,
+	UBIFS_XENT_KEY,
+	UBIFS_KEY_TYPES_CNT,
+};
+
+/* Count of LEBs reserved for the superblock area */
+#define UBIFS_SB_LEBS 1
+/* Count of LEBs reserved for the master area */
+#define UBIFS_MST_LEBS 2
+
+/* First LEB of the superblock area */
+#define UBIFS_SB_LNUM 0
+/* First LEB of the master area */
+#define UBIFS_MST_LNUM (UBIFS_SB_LNUM + UBIFS_SB_LEBS)
+/* First LEB of the log area */
+#define UBIFS_LOG_LNUM (UBIFS_MST_LNUM + UBIFS_MST_LEBS)
+
+/*
+ * The below constants define the absolute minimum values for various UBIFS
+ * media areas. Many of them actually depend of flash geometry and the FS
+ * configuration (number of journal heads, orphan LEBs, etc). This means that
+ * the smallest volume size which can be used for UBIFS cannot be pre-defined
+ * by these constants. The file-system that meets the below limitation will not
+ * necessarily mount. UBIFS does run-time calculations and validates the FS
+ * size.
+ */
+
+/* Minimum number of logical eraseblocks in the log */
+#define UBIFS_MIN_LOG_LEBS 2
+/* Minimum number of bud logical eraseblocks (one for each head) */
+#define UBIFS_MIN_BUD_LEBS 3
+/* Minimum number of journal logical eraseblocks */
+#define UBIFS_MIN_JNL_LEBS (UBIFS_MIN_LOG_LEBS + UBIFS_MIN_BUD_LEBS)
+/* Minimum number of LPT area logical eraseblocks */
+#define UBIFS_MIN_LPT_LEBS 2
+/* Minimum number of orphan area logical eraseblocks */
+#define UBIFS_MIN_ORPH_LEBS 1
+/*
+ * Minimum number of main area logical eraseblocks (buds, 2 for the index, 1
+ * for GC, 1 for deletions, and at least 1 for committed data).
+ */
+#define UBIFS_MIN_MAIN_LEBS (UBIFS_MIN_BUD_LEBS + 5)
+
+/* Minimum number of logical eraseblocks */
+#define UBIFS_MIN_LEB_CNT (UBIFS_SB_LEBS + UBIFS_MST_LEBS + \
+			   UBIFS_MIN_LOG_LEBS + UBIFS_MIN_LPT_LEBS + \
+			   UBIFS_MIN_ORPH_LEBS + UBIFS_MIN_MAIN_LEBS)
+
+/* Node sizes (N.B. these are guaranteed to be multiples of 8) */
+#define UBIFS_CH_SZ        sizeof(struct ubifs_ch)
+#define UBIFS_INO_NODE_SZ  sizeof(struct ubifs_ino_node)
+#define UBIFS_DATA_NODE_SZ sizeof(struct ubifs_data_node)
+#define UBIFS_DENT_NODE_SZ sizeof(struct ubifs_dent_node)
+#define UBIFS_TRUN_NODE_SZ sizeof(struct ubifs_trun_node)
+#define UBIFS_PAD_NODE_SZ  sizeof(struct ubifs_pad_node)
+#define UBIFS_SB_NODE_SZ   sizeof(struct ubifs_sb_node)
+#define UBIFS_MST_NODE_SZ  sizeof(struct ubifs_mst_node)
+#define UBIFS_REF_NODE_SZ  sizeof(struct ubifs_ref_node)
+#define UBIFS_IDX_NODE_SZ  sizeof(struct ubifs_idx_node)
+#define UBIFS_CS_NODE_SZ   sizeof(struct ubifs_cs_node)
+#define UBIFS_ORPH_NODE_SZ sizeof(struct ubifs_orph_node)
+/* Extended attribute entry nodes are identical to directory entry nodes */
+#define UBIFS_XENT_NODE_SZ UBIFS_DENT_NODE_SZ
+/* Only this does not have to be multiple of 8 bytes */
+#define UBIFS_BRANCH_SZ    sizeof(struct ubifs_branch)
+
+/* Maximum node sizes (N.B. these are guaranteed to be multiples of 8) */
+#define UBIFS_MAX_DATA_NODE_SZ  (UBIFS_DATA_NODE_SZ + UBIFS_BLOCK_SIZE)
+#define UBIFS_MAX_INO_NODE_SZ   (UBIFS_INO_NODE_SZ + UBIFS_MAX_INO_DATA)
+#define UBIFS_MAX_DENT_NODE_SZ  (UBIFS_DENT_NODE_SZ + UBIFS_MAX_NLEN + 1)
+#define UBIFS_MAX_XENT_NODE_SZ  UBIFS_MAX_DENT_NODE_SZ
+
+/* The largest UBIFS node */
+#define UBIFS_MAX_NODE_SZ UBIFS_MAX_INO_NODE_SZ
+
+/*
+ * On-flash inode flags.
+ *
+ * UBIFS_COMPR_FL: use compression for this inode
+ * UBIFS_SYNC_FL:  I/O on this inode has to be synchronous
+ * UBIFS_IMMUTABLE_FL: inode is immutable
+ * UBIFS_APPEND_FL: writes to the inode may only append data
+ * UBIFS_DIRSYNC_FL: I/O on this directory inode has to be synchronous
+ * UBIFS_XATTR_FL: this inode is the inode for an extended attribute value
+ *
+ * Note, these are on-flash flags which correspond to ioctl flags
+ * (@FS_COMPR_FL, etc). They have the same values now, but generally, do not
+ * have to be the same.
+ */
+enum {
+	UBIFS_COMPR_FL     = 0x01,
+	UBIFS_SYNC_FL      = 0x02,
+	UBIFS_IMMUTABLE_FL = 0x04,
+	UBIFS_APPEND_FL    = 0x08,
+	UBIFS_DIRSYNC_FL   = 0x10,
+	UBIFS_XATTR_FL     = 0x20,
+};
+
+/* Inode flag bits used by UBIFS */
+#define UBIFS_FL_MASK 0x0000001F
+
+/*
+ * UBIFS compression algorithms.
+ *
+ * UBIFS_COMPR_NONE: no compression
+ * UBIFS_COMPR_LZO: LZO compression
+ * UBIFS_COMPR_ZLIB: ZLIB compression
+ * UBIFS_COMPR_TYPES_CNT: count of supported compression types
+ */
+enum {
+	UBIFS_COMPR_NONE,
+	UBIFS_COMPR_LZO,
+	UBIFS_COMPR_ZLIB,
+	UBIFS_COMPR_TYPES_CNT,
+};
+
+/*
+ * UBIFS node types.
+ *
+ * UBIFS_INO_NODE: inode node
+ * UBIFS_DATA_NODE: data node
+ * UBIFS_DENT_NODE: directory entry node
+ * UBIFS_XENT_NODE: extended attribute node
+ * UBIFS_TRUN_NODE: truncation node
+ * UBIFS_PAD_NODE: padding node
+ * UBIFS_SB_NODE: superblock node
+ * UBIFS_MST_NODE: master node
+ * UBIFS_REF_NODE: LEB reference node
+ * UBIFS_IDX_NODE: index node
+ * UBIFS_CS_NODE: commit start node
+ * UBIFS_ORPH_NODE: orphan node
+ * UBIFS_NODE_TYPES_CNT: count of supported node types
+ *
+ * Note, we index arrays by these numbers, so keep them low and contiguous.
+ * Node type constants for inodes, direntries and so on have to be the same as
+ * corresponding key type constants.
+ */
+enum {
+	UBIFS_INO_NODE,
+	UBIFS_DATA_NODE,
+	UBIFS_DENT_NODE,
+	UBIFS_XENT_NODE,
+	UBIFS_TRUN_NODE,
+	UBIFS_PAD_NODE,
+	UBIFS_SB_NODE,
+	UBIFS_MST_NODE,
+	UBIFS_REF_NODE,
+	UBIFS_IDX_NODE,
+	UBIFS_CS_NODE,
+	UBIFS_ORPH_NODE,
+	UBIFS_NODE_TYPES_CNT,
+};
+
+/*
+ * Master node flags.
+ *
+ * UBIFS_MST_DIRTY: rebooted uncleanly - master node is dirty
+ * UBIFS_MST_NO_ORPHS: no orphan inodes present
+ * UBIFS_MST_RCVRY: written by recovery
+ */
+enum {
+	UBIFS_MST_DIRTY = 1,
+	UBIFS_MST_NO_ORPHS = 2,
+	UBIFS_MST_RCVRY = 4,
+};
+
+/*
+ * Node group type (used by recovery to recover whole group or none).
+ *
+ * UBIFS_NO_NODE_GROUP: this node is not part of a group
+ * UBIFS_IN_NODE_GROUP: this node is a part of a group
+ * UBIFS_LAST_OF_NODE_GROUP: this node is the last in a group
+ */
+enum {
+	UBIFS_NO_NODE_GROUP = 0,
+	UBIFS_IN_NODE_GROUP,
+	UBIFS_LAST_OF_NODE_GROUP,
+};
+
+/*
+ * Superblock flags.
+ *
+ * UBIFS_FLG_BIGLPT: if "big" LPT model is used if set
+ */
+enum {
+	UBIFS_FLG_BIGLPT = 0x02,
+};
+
+/**
+ * struct ubifs_ch - common header node.
+ * @magic: UBIFS node magic number (%UBIFS_NODE_MAGIC)
+ * @crc: CRC-32 checksum of the node header
+ * @sqnum: sequence number
+ * @len: full node length
+ * @node_type: node type
+ * @group_type: node group type
+ * @padding: reserved for future, zeroes
+ *
+ * Every UBIFS node starts with this common part. If the node has a key, the
+ * key always goes next.
+ */
+struct ubifs_ch {
+	__le32 magic;
+	__le32 crc;
+	__le64 sqnum;
+	__le32 len;
+	__u8 node_type;
+	__u8 group_type;
+	__u8 padding[2];
+} __attribute__ ((packed));
+
+/**
+ * union ubifs_dev_desc - device node descriptor.
+ * @new: new type device descriptor
+ * @huge: huge type device descriptor
+ *
+ * This data structure describes major/minor numbers of a device node. In an
+ * inode is a device node then its data contains an object of this type. UBIFS
+ * uses standard Linux "new" and "huge" device node encodings.
+ */
+union ubifs_dev_desc {
+	__le32 new;
+	__le64 huge;
+} __attribute__ ((packed));
+
+/**
+ * struct ubifs_ino_node - inode node.
+ * @ch: common header
+ * @key: node key
+ * @creat_sqnum: sequence number at time of creation
+ * @size: inode size in bytes (amount of uncompressed data)
+ * @atime_sec: access time seconds
+ * @ctime_sec: creation time seconds
+ * @mtime_sec: modification time seconds
+ * @atime_nsec: access time nanoseconds
+ * @ctime_nsec: creation time nanoseconds
+ * @mtime_nsec: modification time nanoseconds
+ * @nlink: number of hard links
+ * @uid: owner ID
+ * @gid: group ID
+ * @mode: access flags
+ * @flags: per-inode flags (%UBIFS_COMPR_FL, %UBIFS_SYNC_FL, etc)
+ * @data_len: inode data length
+ * @xattr_cnt: count of extended attributes this inode has
+ * @xattr_size: summarized size of all extended attributes in bytes
+ * @padding1: reserved for future, zeroes
+ * @xattr_names: sum of lengths of all extended attribute names belonging to
+ *               this inode
+ * @compr_type: compression type used for this inode
+ * @padding2: reserved for future, zeroes
+ * @data: data attached to the inode
+ *
+ * Note, even though inode compression type is defined by @compr_type, some
+ * nodes of this inode may be compressed with different compressor - this
+ * happens if compression type is changed while the inode already has data
+ * nodes. But @compr_type will be use for further writes to the inode.
+ *
+ * Note, do not forget to amend 'zero_ino_node_unused()' function when changing
+ * the padding fields.
+ */
+struct ubifs_ino_node {
+	struct ubifs_ch ch;
+	__u8 key[UBIFS_MAX_KEY_LEN];
+	__le64 creat_sqnum;
+	__le64 size;
+	__le64 atime_sec;
+	__le64 ctime_sec;
+	__le64 mtime_sec;
+	__le32 atime_nsec;
+	__le32 ctime_nsec;
+	__le32 mtime_nsec;
+	__le32 nlink;
+	__le32 uid;
+	__le32 gid;
+	__le32 mode;
+	__le32 flags;
+	__le32 data_len;
+	__le32 xattr_cnt;
+	__le32 xattr_size;
+	__u8 padding1[4]; /* Watch 'zero_ino_node_unused()' if changing! */
+	__le32 xattr_names;
+	__le16 compr_type;
+	__u8 padding2[26]; /* Watch 'zero_ino_node_unused()' if changing! */
+	__u8 data[];
+} __attribute__ ((packed));
+
+/**
+ * struct ubifs_dent_node - directory entry node.
+ * @ch: common header
+ * @key: node key
+ * @inum: target inode number
+ * @padding1: reserved for future, zeroes
+ * @type: type of the target inode (%UBIFS_ITYPE_REG, %UBIFS_ITYPE_DIR, etc)
+ * @nlen: name length
+ * @padding2: reserved for future, zeroes
+ * @name: zero-terminated name
+ *
+ * Note, do not forget to amend 'zero_dent_node_unused()' function when
+ * changing the padding fields.
+ */
+struct ubifs_dent_node {
+	struct ubifs_ch ch;
+	__u8 key[UBIFS_MAX_KEY_LEN];
+	__le64 inum;
+	__u8 padding1;
+	__u8 type;
+	__le16 nlen;
+	__u8 padding2[4]; /* Watch 'zero_dent_node_unused()' if changing! */
+	__u8 name[];
+} __attribute__ ((packed));
+
+/**
+ * struct ubifs_data_node - data node.
+ * @ch: common header
+ * @key: node key
+ * @size: uncompressed data size in bytes
+ * @compr_type: compression type (%UBIFS_COMPR_NONE, %UBIFS_COMPR_LZO, etc)
+ * @padding: reserved for future, zeroes
+ * @data: data
+ *
+ * Note, do not forget to amend 'zero_data_node_unused()' function when
+ * changing the padding fields.
+ */
+struct ubifs_data_node {
+	struct ubifs_ch ch;
+	__u8 key[UBIFS_MAX_KEY_LEN];
+	__le32 size;
+	__le16 compr_type;
+	__u8 padding[2]; /* Watch 'zero_data_node_unused()' if changing! */
+	__u8 data[];
+} __attribute__ ((packed));
+
+/**
+ * struct ubifs_trun_node - truncation node.
+ * @ch: common header
+ * @inum: truncated inode number
+ * @padding: reserved for future, zeroes
+ * @old_size: size before truncation
+ * @new_size: size after truncation
+ *
+ * This node exists only in the journal and never goes to the main area. Note,
+ * do not forget to amend 'zero_trun_node_unused()' function when changing the
+ * padding fields.
+ */
+struct ubifs_trun_node {
+	struct ubifs_ch ch;
+	__le32 inum;
+	__u8 padding[12]; /* Watch 'zero_trun_node_unused()' if changing! */
+	__le64 old_size;
+	__le64 new_size;
+} __attribute__ ((packed));
+
+/**
+ * struct ubifs_pad_node - padding node.
+ * @ch: common header
+ * @pad_len: how many bytes after this node are unused (because padded)
+ * @padding: reserved for future, zeroes
+ */
+struct ubifs_pad_node {
+	struct ubifs_ch ch;
+	__le32 pad_len;
+} __attribute__ ((packed));
+
+/**
+ * struct ubifs_sb_node - superblock node.
+ * @ch: common header
+ * @padding: reserved for future, zeroes
+ * @key_hash: type of hash function used in keys
+ * @key_fmt: format of the key
+ * @flags: file-system flags (%UBIFS_FLG_BIGLPT, etc)
+ * @min_io_size: minimal input/output unit size
+ * @leb_size: logical eraseblock size in bytes
+ * @leb_cnt: count of LEBs used by file-system
+ * @max_leb_cnt: maximum count of LEBs used by file-system
+ * @max_bud_bytes: maximum amount of data stored in buds
+ * @log_lebs: log size in logical eraseblocks
+ * @lpt_lebs: number of LEBs used for lprops table
+ * @orph_lebs: number of LEBs used for recording orphans
+ * @jhead_cnt: count of journal heads
+ * @fanout: tree fanout (max. number of links per indexing node)
+ * @lsave_cnt: number of LEB numbers in LPT's save table
+ * @fmt_version: UBIFS on-flash format version
+ * @default_compr: default compression algorithm (%UBIFS_COMPR_LZO, etc)
+ * @padding1: reserved for future, zeroes
+ * @rp_uid: reserve pool UID
+ * @rp_gid: reserve pool GID
+ * @rp_size: size of the reserved pool in bytes
+ * @padding2: reserved for future, zeroes
+ * @time_gran: time granularity in nanoseconds
+ * @uuid: UUID generated when the file system image was created
+ */
+struct ubifs_sb_node {
+	struct ubifs_ch ch;
+	__u8 padding[2];
+	__u8 key_hash;
+	__u8 key_fmt;
+	__le32 flags;
+	__le32 min_io_size;
+	__le32 leb_size;
+	__le32 leb_cnt;
+	__le32 max_leb_cnt;
+	__le64 max_bud_bytes;
+	__le32 log_lebs;
+	__le32 lpt_lebs;
+	__le32 orph_lebs;
+	__le32 jhead_cnt;
+	__le32 fanout;
+	__le32 lsave_cnt;
+	__le32 fmt_version;
+	__le16 default_compr;
+	__u8 padding1[2];
+	__le32 rp_uid;
+	__le32 rp_gid;
+	__le64 rp_size;
+	__le32 time_gran;
+	__u8 uuid[16];
+	__u8 padding2[3972];
+} __attribute__ ((packed));
+
+/**
+ * struct ubifs_mst_node - master node.
+ * @ch: common header
+ * @highest_inum: highest inode number in the committed index
+ * @cmt_no: commit number
+ * @flags: various flags (%UBIFS_MST_DIRTY, etc)
+ * @log_lnum: start of the log
+ * @root_lnum: LEB number of the root indexing node
+ * @root_offs: offset within @root_lnum
+ * @root_len: root indexing node length
+ * @gc_lnum: LEB reserved for garbage collection (%-1 value means the LEB was
+ * not reserved and should be reserved on mount)
+ * @ihead_lnum: LEB number of index head
+ * @ihead_offs: offset of index head
+ * @index_size: size of index on flash
+ * @total_free: total free space in bytes
+ * @total_dirty: total dirty space in bytes
+ * @total_used: total used space in bytes (includes only data LEBs)
+ * @total_dead: total dead space in bytes (includes only data LEBs)
+ * @total_dark: total dark space in bytes (includes only data LEBs)
+ * @lpt_lnum: LEB number of LPT root nnode
+ * @lpt_offs: offset of LPT root nnode
+ * @nhead_lnum: LEB number of LPT head
+ * @nhead_offs: offset of LPT head
+ * @ltab_lnum: LEB number of LPT's own lprops table
+ * @ltab_offs: offset of LPT's own lprops table
+ * @lsave_lnum: LEB number of LPT's save table (big model only)
+ * @lsave_offs: offset of LPT's save table (big model only)
+ * @lscan_lnum: LEB number of last LPT scan
+ * @empty_lebs: number of empty logical eraseblocks
+ * @idx_lebs: number of indexing logical eraseblocks
+ * @leb_cnt: count of LEBs used by file-system
+ * @padding: reserved for future, zeroes
+ */
+struct ubifs_mst_node {
+	struct ubifs_ch ch;
+	__le64 highest_inum;
+	__le64 cmt_no;
+	__le32 flags;
+	__le32 log_lnum;
+	__le32 root_lnum;
+	__le32 root_offs;
+	__le32 root_len;
+	__le32 gc_lnum;
+	__le32 ihead_lnum;
+	__le32 ihead_offs;
+	__le64 index_size;
+	__le64 total_free;
+	__le64 total_dirty;
+	__le64 total_used;
+	__le64 total_dead;
+	__le64 total_dark;
+	__le32 lpt_lnum;
+	__le32 lpt_offs;
+	__le32 nhead_lnum;
+	__le32 nhead_offs;
+	__le32 ltab_lnum;
+	__le32 ltab_offs;
+	__le32 lsave_lnum;
+	__le32 lsave_offs;
+	__le32 lscan_lnum;
+	__le32 empty_lebs;
+	__le32 idx_lebs;
+	__le32 leb_cnt;
+	__u8 padding[344];
+} __attribute__ ((packed));
+
+/**
+ * struct ubifs_ref_node - logical eraseblock reference node.
+ * @ch: common header
+ * @lnum: the referred logical eraseblock number
+ * @offs: start offset in the referred LEB
+ * @jhead: journal head number
+ * @padding: reserved for future, zeroes
+ */
+struct ubifs_ref_node {
+	struct ubifs_ch ch;
+	__le32 lnum;
+	__le32 offs;
+	__le32 jhead;
+	__u8 padding[28];
+} __attribute__ ((packed));
+
+/**
+ * struct ubifs_branch - key/reference/length branch
+ * @lnum: LEB number of the target node
+ * @offs: offset within @lnum
+ * @len: target node length
+ * @key: key
+ */
+struct ubifs_branch {
+	__le32 lnum;
+	__le32 offs;
+	__le32 len;
+	__u8 key[];
+} __attribute__ ((packed));
+
+/**
+ * struct ubifs_idx_node - indexing node.
+ * @ch: common header
+ * @child_cnt: number of child index nodes
+ * @level: tree level
+ * @branches: LEB number / offset / length / key branches
+ */
+struct ubifs_idx_node {
+	struct ubifs_ch ch;
+	__le16 child_cnt;
+	__le16 level;
+	__u8 branches[];
+} __attribute__ ((packed));
+
+/**
+ * struct ubifs_cs_node - commit start node.
+ * @ch: common header
+ * @cmt_no: commit number
+ */
+struct ubifs_cs_node {
+	struct ubifs_ch ch;
+	__le64 cmt_no;
+} __attribute__ ((packed));
+
+/**
+ * struct ubifs_orph_node - orphan node.
+ * @ch: common header
+ * @cmt_no: commit number (also top bit is set on the last node of the commit)
+ * @inos: inode numbers of orphans
+ */
+struct ubifs_orph_node {
+	struct ubifs_ch ch;
+	__le64 cmt_no;
+	__le64 inos[];
+} __attribute__ ((packed));
+
+#endif /* __UBIFS_MEDIA_H__ */
diff --git a/fs/ubifs/ubifs.h b/fs/ubifs/ubifs.h
new file mode 100644
index 00000000000..e4f89f27182
--- /dev/null
+++ b/fs/ubifs/ubifs.h
@@ -0,0 +1,1649 @@
+/*
+ * This file is part of UBIFS.
+ *
+ * Copyright (C) 2006-2008 Nokia Corporation
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 as published by
+ * the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
+ * more details.
+ *
+ * You should have received a copy of the GNU General Public License along with
+ * this program; if not, write to the Free Software Foundation, Inc., 51
+ * Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
+ *
+ * Authors: Artem Bityutskiy (Битюцкий Артём)
+ *          Adrian Hunter
+ */
+
+/* Implementation version 0.7 */
+
+#ifndef __UBIFS_H__
+#define __UBIFS_H__
+
+#include <asm/div64.h>
+#include <linux/statfs.h>
+#include <linux/fs.h>
+#include <linux/err.h>
+#include <linux/sched.h>
+#include <linux/vmalloc.h>
+#include <linux/spinlock.h>
+#include <linux/mutex.h>
+#include <linux/rwsem.h>
+#include <linux/mtd/ubi.h>
+#include <linux/pagemap.h>
+#include <linux/backing-dev.h>
+#include "ubifs-media.h"
+
+/* Version of this UBIFS implementation */
+#define UBIFS_VERSION 1
+
+/* Normal UBIFS messages */
+#define ubifs_msg(fmt, ...) \
+		printk(KERN_NOTICE "UBIFS: " fmt "\n", ##__VA_ARGS__)
+/* UBIFS error messages */
+#define ubifs_err(fmt, ...)                                                  \
+	printk(KERN_ERR "UBIFS error (pid %d): %s: " fmt "\n", current->pid, \
+	       __func__, ##__VA_ARGS__)
+/* UBIFS warning messages */
+#define ubifs_warn(fmt, ...)                                         \
+	printk(KERN_WARNING "UBIFS warning (pid %d): %s: " fmt "\n", \
+	       current->pid, __func__, ##__VA_ARGS__)
+
+/* UBIFS file system VFS magic number */
+#define UBIFS_SUPER_MAGIC 0x24051905
+
+/* Number of UBIFS blocks per VFS page */
+#define UBIFS_BLOCKS_PER_PAGE (PAGE_CACHE_SIZE / UBIFS_BLOCK_SIZE)
+#define UBIFS_BLOCKS_PER_PAGE_SHIFT (PAGE_CACHE_SHIFT - UBIFS_BLOCK_SHIFT)
+
+/* "File system end of life" sequence number watermark */
+#define SQNUM_WARN_WATERMARK 0xFFFFFFFF00000000ULL
+#define SQNUM_WATERMARK      0xFFFFFFFFFF000000ULL
+
+/* Minimum amount of data UBIFS writes to the flash */
+#define MIN_WRITE_SZ (UBIFS_DATA_NODE_SZ + 8)
+
+/*
+ * Currently we do not support inode number overlapping and re-using, so this
+ * watermark defines dangerous inode number level. This should be fixed later,
+ * although it is difficult to exceed current limit. Another option is to use
+ * 64-bit inode numbers, but this means more overhead.
+ */
+#define INUM_WARN_WATERMARK 0xFFF00000
+#define INUM_WATERMARK      0xFFFFFF00
+
+/* Largest key size supported in this implementation */
+#define CUR_MAX_KEY_LEN UBIFS_SK_LEN
+
+/* Maximum number of entries in each LPT (LEB category) heap */
+#define LPT_HEAP_SZ 256
+
+/*
+ * Background thread name pattern. The numbers are UBI device and volume
+ * numbers.
+ */
+#define BGT_NAME_PATTERN "ubifs_bgt%d_%d"
+
+/* Default write-buffer synchronization timeout (5 secs) */
+#define DEFAULT_WBUF_TIMEOUT (5 * HZ)
+
+/* Maximum possible inode number (only 32-bit inodes are supported now) */
+#define MAX_INUM 0xFFFFFFFF
+
+/* Number of non-data journal heads */
+#define NONDATA_JHEADS_CNT 2
+
+/* Garbage collector head */
+#define GCHD   0
+/* Base journal head number */
+#define BASEHD 1
+/* First "general purpose" journal head */
+#define DATAHD 2
+
+/* 'No change' value for 'ubifs_change_lp()' */
+#define LPROPS_NC 0x80000001
+
+/*
+ * There is no notion of truncation key because truncation nodes do not exist
+ * in TNC. However, when replaying, it is handy to introduce fake "truncation"
+ * keys for truncation nodes because the code becomes simpler. So we define
+ * %UBIFS_TRUN_KEY type.
+ */
+#define UBIFS_TRUN_KEY UBIFS_KEY_TYPES_CNT
+
+/*
+ * How much a directory entry/extended attribute entry adds to the parent/host
+ * inode.
+ */
+#define CALC_DENT_SIZE(name_len) ALIGN(UBIFS_DENT_NODE_SZ + (name_len) + 1, 8)
+
+/* How much an extended attribute adds to the host inode */
+#define CALC_XATTR_BYTES(data_len) ALIGN(UBIFS_INO_NODE_SZ + (data_len) + 1, 8)
+
+/*
+ * Znodes which were not touched for 'OLD_ZNODE_AGE' seconds are considered
+ * "old", and znode which were touched last 'YOUNG_ZNODE_AGE' seconds ago are
+ * considered "young". This is used by shrinker when selecting znode to trim
+ * off.
+ */
+#define OLD_ZNODE_AGE 20
+#define YOUNG_ZNODE_AGE 5
+
+/*
+ * Some compressors, like LZO, may end up with more data then the input buffer.
+ * So UBIFS always allocates larger output buffer, to be sure the compressor
+ * will not corrupt memory in case of worst case compression.
+ */
+#define WORST_COMPR_FACTOR 2
+
+/* Maximum expected tree height for use by bottom_up_buf */
+#define BOTTOM_UP_HEIGHT 64
+
+/*
+ * Lockdep classes for UBIFS inode @ui_mutex.
+ */
+enum {
+	WB_MUTEX_1 = 0,
+	WB_MUTEX_2 = 1,
+	WB_MUTEX_3 = 2,
+};
+
+/*
+ * Znode flags (actually, bit numbers which store the flags).
+ *
+ * DIRTY_ZNODE: znode is dirty
+ * COW_ZNODE: znode is being committed and a new instance of this znode has to
+ *            be created before changing this znode
+ * OBSOLETE_ZNODE: znode is obsolete, which means it was deleted, but it is
+ *                 still in the commit list and the ongoing commit operation
+ *                 will commit it, and delete this znode after it is done
+ */
+enum {
+	DIRTY_ZNODE    = 0,
+	COW_ZNODE      = 1,
+	OBSOLETE_ZNODE = 2,
+};
+
+/*
+ * Commit states.
+ *
+ * COMMIT_RESTING: commit is not wanted
+ * COMMIT_BACKGROUND: background commit has been requested
+ * COMMIT_REQUIRED: commit is required
+ * COMMIT_RUNNING_BACKGROUND: background commit is running
+ * COMMIT_RUNNING_REQUIRED: commit is running and it is required
+ * COMMIT_BROKEN: commit failed
+ */
+enum {
+	COMMIT_RESTING = 0,
+	COMMIT_BACKGROUND,
+	COMMIT_REQUIRED,
+	COMMIT_RUNNING_BACKGROUND,
+	COMMIT_RUNNING_REQUIRED,
+	COMMIT_BROKEN,
+};
+
+/*
+ * 'ubifs_scan_a_node()' return values.
+ *
+ * SCANNED_GARBAGE:  scanned garbage
+ * SCANNED_EMPTY_SPACE: scanned empty space
+ * SCANNED_A_NODE: scanned a valid node
+ * SCANNED_A_CORRUPT_NODE: scanned a corrupted node
+ * SCANNED_A_BAD_PAD_NODE: scanned a padding node with invalid pad length
+ *
+ * Greater than zero means: 'scanned that number of padding bytes'
+ */
+enum {
+	SCANNED_GARBAGE        = 0,
+	SCANNED_EMPTY_SPACE    = -1,
+	SCANNED_A_NODE         = -2,
+	SCANNED_A_CORRUPT_NODE = -3,
+	SCANNED_A_BAD_PAD_NODE = -4,
+};
+
+/*
+ * LPT cnode flag bits.
+ *
+ * DIRTY_CNODE: cnode is dirty
+ * COW_CNODE: cnode is being committed and must be copied before writing
+ * OBSOLETE_CNODE: cnode is being committed and has been copied (or deleted),
+ * so it can (and must) be freed when the commit is finished
+ */
+enum {
+	DIRTY_CNODE    = 0,
+	COW_CNODE      = 1,
+	OBSOLETE_CNODE = 2,
+};
+
+/*
+ * Dirty flag bits (lpt_drty_flgs) for LPT special nodes.
+ *
+ * LTAB_DIRTY: ltab node is dirty
+ * LSAVE_DIRTY: lsave node is dirty
+ */
+enum {
+	LTAB_DIRTY  = 1,
+	LSAVE_DIRTY = 2,
+};
+
+/*
+ * Return codes used by the garbage collector.
+ * @LEB_FREED: the logical eraseblock was freed and is ready to use
+ * @LEB_FREED_IDX: indexing LEB was freed and can be used only after the commit
+ * @LEB_RETAINED: the logical eraseblock was freed and retained for GC purposes
+ */
+enum {
+	LEB_FREED,
+	LEB_FREED_IDX,
+	LEB_RETAINED,
+};
+
+/**
+ * struct ubifs_old_idx - index node obsoleted since last commit start.
+ * @rb: rb-tree node
+ * @lnum: LEB number of obsoleted index node
+ * @offs: offset of obsoleted index node
+ */
+struct ubifs_old_idx {
+	struct rb_node rb;
+	int lnum;
+	int offs;
+};
+
+/* The below union makes it easier to deal with keys */
+union ubifs_key {
+	uint8_t u8[CUR_MAX_KEY_LEN];
+	uint32_t u32[CUR_MAX_KEY_LEN/4];
+	uint64_t u64[CUR_MAX_KEY_LEN/8];
+	__le32 j32[CUR_MAX_KEY_LEN/4];
+};
+
+/**
+ * struct ubifs_scan_node - UBIFS scanned node information.
+ * @list: list of scanned nodes
+ * @key: key of node scanned (if it has one)
+ * @sqnum: sequence number
+ * @type: type of node scanned
+ * @offs: offset with LEB of node scanned
+ * @len: length of node scanned
+ * @node: raw node
+ */
+struct ubifs_scan_node {
+	struct list_head list;
+	union ubifs_key key;
+	unsigned long long sqnum;
+	int type;
+	int offs;
+	int len;
+	void *node;
+};
+
+/**
+ * struct ubifs_scan_leb - UBIFS scanned LEB information.
+ * @lnum: logical eraseblock number
+ * @nodes_cnt: number of nodes scanned
+ * @nodes: list of struct ubifs_scan_node
+ * @endpt: end point (and therefore the start of empty space)
+ * @ecc: read returned -EBADMSG
+ * @buf: buffer containing entire LEB scanned
+ */
+struct ubifs_scan_leb {
+	int lnum;
+	int nodes_cnt;
+	struct list_head nodes;
+	int endpt;
+	int ecc;
+	void *buf;
+};
+
+/**
+ * struct ubifs_gced_idx_leb - garbage-collected indexing LEB.
+ * @list: list
+ * @lnum: LEB number
+ * @unmap: OK to unmap this LEB
+ *
+ * This data structure is used to temporary store garbage-collected indexing
+ * LEBs - they are not released immediately, but only after the next commit.
+ * This is needed to guarantee recoverability.
+ */
+struct ubifs_gced_idx_leb {
+	struct list_head list;
+	int lnum;
+	int unmap;
+};
+
+/**
+ * struct ubifs_inode - UBIFS in-memory inode description.
+ * @vfs_inode: VFS inode description object
+ * @creat_sqnum: sequence number at time of creation
+ * @xattr_size: summarized size of all extended attributes in bytes
+ * @xattr_cnt: count of extended attributes this inode has
+ * @xattr_names: sum of lengths of all extended attribute names belonging to
+ *               this inode
+ * @dirty: non-zero if the inode is dirty
+ * @xattr: non-zero if this is an extended attribute inode
+ * @ui_mutex: serializes inode write-back with the rest of VFS operations,
+ *            serializes "clean <-> dirty" state changes, protects @dirty,
+ *            @ui_size, and @xattr_size
+ * @ui_lock: protects @synced_i_size
+ * @synced_i_size: synchronized size of inode, i.e. the value of inode size
+ *                 currently stored on the flash; used only for regular file
+ *                 inodes
+ * @ui_size: inode size used by UBIFS when writing to flash
+ * @flags: inode flags (@UBIFS_COMPR_FL, etc)
+ * @compr_type: default compression type used for this inode
+ * @data_len: length of the data attached to the inode
+ * @data: inode's data
+ *
+ * @ui_mutex exists for two main reasons. At first it prevents inodes from
+ * being written back while UBIFS changing them, being in the middle of an VFS
+ * operation. This way UBIFS makes sure the inode fields are consistent. For
+ * example, in 'ubifs_rename()' we change 3 inodes simultaneously, and
+ * write-back must not write any of them before we have finished.
+ *
+ * The second reason is budgeting - UBIFS has to budget all operations. If an
+ * operation is going to mark an inode dirty, it has to allocate budget for
+ * this. It cannot just mark it dirty because there is no guarantee there will
+ * be enough flash space to write the inode back later. This means UBIFS has
+ * to have full control over inode "clean <-> dirty" transitions (and pages
+ * actually). But unfortunately, VFS marks inodes dirty in many places, and it
+ * does not ask the file-system if it is allowed to do so (there is a notifier,
+ * but it is not enough), i.e., there is no mechanism to synchronize with this.
+ * So UBIFS has its own inode dirty flag and its own mutex to serialize
+ * "clean <-> dirty" transitions.
+ *
+ * The @synced_i_size field is used to make sure we never write pages which are
+ * beyond last synchronized inode size. See 'ubifs_writepage()' for more
+ * information.
+ *
+ * The @ui_size is a "shadow" variable for @inode->i_size and UBIFS uses
+ * @ui_size instead of @inode->i_size. The reason for this is that UBIFS cannot
+ * make sure @inode->i_size is always changed under @ui_mutex, because it
+ * cannot call 'vmtruncate()' with @ui_mutex locked, because it would deadlock
+ * with 'ubifs_writepage()' (see file.c). All the other inode fields are
+ * changed under @ui_mutex, so they do not need "shadow" fields. Note, one
+ * could consider to rework locking and base it on "shadow" fields.
+ */
+struct ubifs_inode {
+	struct inode vfs_inode;
+	unsigned long long creat_sqnum;
+	unsigned int xattr_size;
+	unsigned int xattr_cnt;
+	unsigned int xattr_names;
+	unsigned int dirty:1;
+	unsigned int xattr:1;
+	struct mutex ui_mutex;
+	spinlock_t ui_lock;
+	loff_t synced_i_size;
+	loff_t ui_size;
+	int flags;
+	int compr_type;
+	int data_len;
+	void *data;
+};
+
+/**
+ * struct ubifs_unclean_leb - records a LEB recovered under read-only mode.
+ * @list: list
+ * @lnum: LEB number of recovered LEB
+ * @endpt: offset where recovery ended
+ *
+ * This structure records a LEB identified during recovery that needs to be
+ * cleaned but was not because UBIFS was mounted read-only. The information
+ * is used to clean the LEB when remounting to read-write mode.
+ */
+struct ubifs_unclean_leb {
+	struct list_head list;
+	int lnum;
+	int endpt;
+};
+
+/*
+ * LEB properties flags.
+ *
+ * LPROPS_UNCAT: not categorized
+ * LPROPS_DIRTY: dirty > 0, not index
+ * LPROPS_DIRTY_IDX: dirty + free > UBIFS_CH_SZ and index
+ * LPROPS_FREE: free > 0, not empty, not index
+ * LPROPS_HEAP_CNT: number of heaps used for storing categorized LEBs
+ * LPROPS_EMPTY: LEB is empty, not taken
+ * LPROPS_FREEABLE: free + dirty == leb_size, not index, not taken
+ * LPROPS_FRDI_IDX: free + dirty == leb_size and index, may be taken
+ * LPROPS_CAT_MASK: mask for the LEB categories above
+ * LPROPS_TAKEN: LEB was taken (this flag is not saved on the media)
+ * LPROPS_INDEX: LEB contains indexing nodes (this flag also exists on flash)
+ */
+enum {
+	LPROPS_UNCAT     =  0,
+	LPROPS_DIRTY     =  1,
+	LPROPS_DIRTY_IDX =  2,
+	LPROPS_FREE      =  3,
+	LPROPS_HEAP_CNT  =  3,
+	LPROPS_EMPTY     =  4,
+	LPROPS_FREEABLE  =  5,
+	LPROPS_FRDI_IDX  =  6,
+	LPROPS_CAT_MASK  = 15,
+	LPROPS_TAKEN     = 16,
+	LPROPS_INDEX     = 32,
+};
+
+/**
+ * struct ubifs_lprops - logical eraseblock properties.
+ * @free: amount of free space in bytes
+ * @dirty: amount of dirty space in bytes
+ * @flags: LEB properties flags (see above)
+ * @lnum: LEB number
+ * @list: list of same-category lprops (for LPROPS_EMPTY and LPROPS_FREEABLE)
+ * @hpos: heap position in heap of same-category lprops (other categories)
+ */
+struct ubifs_lprops {
+	int free;
+	int dirty;
+	int flags;
+	int lnum;
+	union {
+		struct list_head list;
+		int hpos;
+	};
+};
+
+/**
+ * struct ubifs_lpt_lprops - LPT logical eraseblock properties.
+ * @free: amount of free space in bytes
+ * @dirty: amount of dirty space in bytes
+ * @tgc: trivial GC flag (1 => unmap after commit end)
+ * @cmt: commit flag (1 => reserved for commit)
+ */
+struct ubifs_lpt_lprops {
+	int free;
+	int dirty;
+	unsigned tgc : 1;
+	unsigned cmt : 1;
+};
+
+/**
+ * struct ubifs_lp_stats - statistics of eraseblocks in the main area.
+ * @empty_lebs: number of empty LEBs
+ * @taken_empty_lebs: number of taken LEBs
+ * @idx_lebs: number of indexing LEBs
+ * @total_free: total free space in bytes
+ * @total_dirty: total dirty space in bytes
+ * @total_used: total used space in bytes (includes only data LEBs)
+ * @total_dead: total dead space in bytes (includes only data LEBs)
+ * @total_dark: total dark space in bytes (includes only data LEBs)
+ *
+ * N.B. total_dirty and total_used are different to other total_* fields,
+ * because they account _all_ LEBs, not just data LEBs.
+ *
+ * 'taken_empty_lebs' counts the LEBs that are in the transient state of having
+ * been 'taken' for use but not yet written to. 'taken_empty_lebs' is needed
+ * to account correctly for gc_lnum, otherwise 'empty_lebs' could be used
+ * by itself (in which case 'unused_lebs' would be a better name). In the case
+ * of gc_lnum, it is 'taken' at mount time or whenever a LEB is retained by GC,
+ * but unlike other empty LEBs that are 'taken', it may not be written straight
+ * away (i.e. before the next commit start or unmount), so either gc_lnum must
+ * be specially accounted for, or the current approach followed i.e. count it
+ * under 'taken_empty_lebs'.
+ */
+struct ubifs_lp_stats {
+	int empty_lebs;
+	int taken_empty_lebs;
+	int idx_lebs;
+	long long total_free;
+	long long total_dirty;
+	long long total_used;
+	long long total_dead;
+	long long total_dark;
+};
+
+struct ubifs_nnode;
+
+/**
+ * struct ubifs_cnode - LEB Properties Tree common node.
+ * @parent: parent nnode
+ * @cnext: next cnode to commit
+ * @flags: flags (%DIRTY_LPT_NODE or %OBSOLETE_LPT_NODE)
+ * @iip: index in parent
+ * @level: level in the tree (zero for pnodes, greater than zero for nnodes)
+ * @num: node number
+ */
+struct ubifs_cnode {
+	struct ubifs_nnode *parent;
+	struct ubifs_cnode *cnext;
+	unsigned long flags;
+	int iip;
+	int level;
+	int num;
+};
+
+/**
+ * struct ubifs_pnode - LEB Properties Tree leaf node.
+ * @parent: parent nnode
+ * @cnext: next cnode to commit
+ * @flags: flags (%DIRTY_LPT_NODE or %OBSOLETE_LPT_NODE)
+ * @iip: index in parent
+ * @level: level in the tree (always zero for pnodes)
+ * @num: node number
+ * @lprops: LEB properties array
+ */
+struct ubifs_pnode {
+	struct ubifs_nnode *parent;
+	struct ubifs_cnode *cnext;
+	unsigned long flags;
+	int iip;
+	int level;
+	int num;
+	struct ubifs_lprops lprops[UBIFS_LPT_FANOUT];
+};
+
+/**
+ * struct ubifs_nbranch - LEB Properties Tree internal node branch.
+ * @lnum: LEB number of child
+ * @offs: offset of child
+ * @nnode: nnode child
+ * @pnode: pnode child
+ * @cnode: cnode child
+ */
+struct ubifs_nbranch {
+	int lnum;
+	int offs;
+	union {
+		struct ubifs_nnode *nnode;
+		struct ubifs_pnode *pnode;
+		struct ubifs_cnode *cnode;
+	};
+};
+
+/**
+ * struct ubifs_nnode - LEB Properties Tree internal node.
+ * @parent: parent nnode
+ * @cnext: next cnode to commit
+ * @flags: flags (%DIRTY_LPT_NODE or %OBSOLETE_LPT_NODE)
+ * @iip: index in parent
+ * @level: level in the tree (always greater than zero for nnodes)
+ * @num: node number
+ * @nbranch: branches to child nodes
+ */
+struct ubifs_nnode {
+	struct ubifs_nnode *parent;
+	struct ubifs_cnode *cnext;
+	unsigned long flags;
+	int iip;
+	int level;
+	int num;
+	struct ubifs_nbranch nbranch[UBIFS_LPT_FANOUT];
+};
+
+/**
+ * struct ubifs_lpt_heap - heap of categorized lprops.
+ * @arr: heap array
+ * @cnt: number in heap
+ * @max_cnt: maximum number allowed in heap
+ *
+ * There are %LPROPS_HEAP_CNT heaps.
+ */
+struct ubifs_lpt_heap {
+	struct ubifs_lprops **arr;
+	int cnt;
+	int max_cnt;
+};
+
+/*
+ * Return codes for LPT scan callback function.
+ *
+ * LPT_SCAN_CONTINUE: continue scanning
+ * LPT_SCAN_ADD: add the LEB properties scanned to the tree in memory
+ * LPT_SCAN_STOP: stop scanning
+ */
+enum {
+	LPT_SCAN_CONTINUE = 0,
+	LPT_SCAN_ADD = 1,
+	LPT_SCAN_STOP = 2,
+};
+
+struct ubifs_info;
+
+/* Callback used by the 'ubifs_lpt_scan_nolock()' function */
+typedef int (*ubifs_lpt_scan_callback)(struct ubifs_info *c,
+				       const struct ubifs_lprops *lprops,
+				       int in_tree, void *data);
+
+/**
+ * struct ubifs_wbuf - UBIFS write-buffer.
+ * @c: UBIFS file-system description object
+ * @buf: write-buffer (of min. flash I/O unit size)
+ * @lnum: logical eraseblock number the write-buffer points to
+ * @offs: write-buffer offset in this logical eraseblock
+ * @avail: number of bytes available in the write-buffer
+ * @used:  number of used bytes in the write-buffer
+ * @dtype: type of data stored in this LEB (%UBI_LONGTERM, %UBI_SHORTTERM,
+ * %UBI_UNKNOWN)
+ * @jhead: journal head the mutex belongs to (note, needed only to shut lockdep
+ *         up by 'mutex_lock_nested()).
+ * @sync_callback: write-buffer synchronization callback
+ * @io_mutex: serializes write-buffer I/O
+ * @lock: serializes @buf, @lnum, @offs, @avail, @used, @next_ino and @inodes
+ *        fields
+ * @timer: write-buffer timer
+ * @timeout: timer expire interval in jiffies
+ * @need_sync: it is set if its timer expired and needs sync
+ * @next_ino: points to the next position of the following inode number
+ * @inodes: stores the inode numbers of the nodes which are in wbuf
+ *
+ * The write-buffer synchronization callback is called when the write-buffer is
+ * synchronized in order to notify how much space was wasted due to
+ * write-buffer padding and how much free space is left in the LEB.
+ *
+ * Note: the fields @buf, @lnum, @offs, @avail and @used can be read under
+ * spin-lock or mutex because they are written under both mutex and spin-lock.
+ * @buf is appended to under mutex but overwritten under both mutex and
+ * spin-lock. Thus the data between @buf and @buf + @used can be read under
+ * spinlock.
+ */
+struct ubifs_wbuf {
+	struct ubifs_info *c;
+	void *buf;
+	int lnum;
+	int offs;
+	int avail;
+	int used;
+	int dtype;
+	int jhead;
+	int (*sync_callback)(struct ubifs_info *c, int lnum, int free, int pad);
+	struct mutex io_mutex;
+	spinlock_t lock;
+	struct timer_list timer;
+	int timeout;
+	int need_sync;
+	int next_ino;
+	ino_t *inodes;
+};
+
+/**
+ * struct ubifs_bud - bud logical eraseblock.
+ * @lnum: logical eraseblock number
+ * @start: where the (uncommitted) bud data starts
+ * @jhead: journal head number this bud belongs to
+ * @list: link in the list buds belonging to the same journal head
+ * @rb: link in the tree of all buds
+ */
+struct ubifs_bud {
+	int lnum;
+	int start;
+	int jhead;
+	struct list_head list;
+	struct rb_node rb;
+};
+
+/**
+ * struct ubifs_jhead - journal head.
+ * @wbuf: head's write-buffer
+ * @buds_list: list of bud LEBs belonging to this journal head
+ *
+ * Note, the @buds list is protected by the @c->buds_lock.
+ */
+struct ubifs_jhead {
+	struct ubifs_wbuf wbuf;
+	struct list_head buds_list;
+};
+
+/**
+ * struct ubifs_zbranch - key/coordinate/length branch stored in znodes.
+ * @key: key
+ * @znode: znode address in memory
+ * @lnum: LEB number of the indexing node
+ * @offs: offset of the indexing node within @lnum
+ * @len: target node length
+ */
+struct ubifs_zbranch {
+	union ubifs_key key;
+	union {
+		struct ubifs_znode *znode;
+		void *leaf;
+	};
+	int lnum;
+	int offs;
+	int len;
+};
+
+/**
+ * struct ubifs_znode - in-memory representation of an indexing node.
+ * @parent: parent znode or NULL if it is the root
+ * @cnext: next znode to commit
+ * @flags: znode flags (%DIRTY_ZNODE, %COW_ZNODE or %OBSOLETE_ZNODE)
+ * @time: last access time (seconds)
+ * @level: level of the entry in the TNC tree
+ * @child_cnt: count of child znodes
+ * @iip: index in parent's zbranch array
+ * @alt: lower bound of key range has altered i.e. child inserted at slot 0
+ * @lnum: LEB number of the corresponding indexing node
+ * @offs: offset of the corresponding indexing node
+ * @len: length  of the corresponding indexing node
+ * @zbranch: array of znode branches (@c->fanout elements)
+ */
+struct ubifs_znode {
+	struct ubifs_znode *parent;
+	struct ubifs_znode *cnext;
+	unsigned long flags;
+	unsigned long time;
+	int level;
+	int child_cnt;
+	int iip;
+	int alt;
+#ifdef CONFIG_UBIFS_FS_DEBUG
+	int lnum, offs, len;
+#endif
+	struct ubifs_zbranch zbranch[];
+};
+
+/**
+ * struct ubifs_node_range - node length range description data structure.
+ * @len: fixed node length
+ * @min_len: minimum possible node length
+ * @max_len: maximum possible node length
+ *
+ * If @max_len is %0, the node has fixed length @len.
+ */
+struct ubifs_node_range {
+	union {
+		int len;
+		int min_len;
+	};
+	int max_len;
+};
+
+/**
+ * struct ubifs_compressor - UBIFS compressor description structure.
+ * @compr_type: compressor type (%UBIFS_COMPR_LZO, etc)
+ * @cc: cryptoapi compressor handle
+ * @comp_mutex: mutex used during compression
+ * @decomp_mutex: mutex used during decompression
+ * @name: compressor name
+ * @capi_name: cryptoapi compressor name
+ */
+struct ubifs_compressor {
+	int compr_type;
+	struct crypto_comp *cc;
+	struct mutex *comp_mutex;
+	struct mutex *decomp_mutex;
+	const char *name;
+	const char *capi_name;
+};
+
+/**
+ * struct ubifs_budget_req - budget requirements of an operation.
+ *
+ * @fast: non-zero if the budgeting should try to aquire budget quickly and
+ *        should not try to call write-back
+ * @recalculate: non-zero if @idx_growth, @data_growth, and @dd_growth fields
+ *               have to be re-calculated
+ * @new_page: non-zero if the operation adds a new page
+ * @dirtied_page: non-zero if the operation makes a page dirty
+ * @new_dent: non-zero if the operation adds a new directory entry
+ * @mod_dent: non-zero if the operation removes or modifies an existing
+ *            directory entry
+ * @new_ino: non-zero if the operation adds a new inode
+ * @new_ino_d: now much data newly created inode contains
+ * @dirtied_ino: how many inodes the operation makes dirty
+ * @dirtied_ino_d: now much data dirtied inode contains
+ * @idx_growth: how much the index will supposedly grow
+ * @data_growth: how much new data the operation will supposedly add
+ * @dd_growth: how much data that makes other data dirty the operation will
+ *             supposedly add
+ *
+ * @idx_growth, @data_growth and @dd_growth are not used in budget request. The
+ * budgeting subsystem caches index and data growth values there to avoid
+ * re-calculating them when the budget is released. However, if @idx_growth is
+ * %-1, it is calculated by the release function using other fields.
+ *
+ * An inode may contain 4KiB of data at max., thus the widths of @new_ino_d
+ * is 13 bits, and @dirtied_ino_d - 15, because up to 4 inodes may be made
+ * dirty by the re-name operation.
+ */
+struct ubifs_budget_req {
+	unsigned int fast:1;
+	unsigned int recalculate:1;
+	unsigned int new_page:1;
+	unsigned int dirtied_page:1;
+	unsigned int new_dent:1;
+	unsigned int mod_dent:1;
+	unsigned int new_ino:1;
+	unsigned int new_ino_d:13;
+#ifndef UBIFS_DEBUG
+	unsigned int dirtied_ino:4;
+	unsigned int dirtied_ino_d:15;
+#else
+	/* Not bit-fields to check for overflows */
+	unsigned int dirtied_ino;
+	unsigned int dirtied_ino_d;
+#endif
+	int idx_growth;
+	int data_growth;
+	int dd_growth;
+};
+
+/**
+ * struct ubifs_orphan - stores the inode number of an orphan.
+ * @rb: rb-tree node of rb-tree of orphans sorted by inode number
+ * @list: list head of list of orphans in order added
+ * @new_list: list head of list of orphans added since the last commit
+ * @cnext: next orphan to commit
+ * @dnext: next orphan to delete
+ * @inum: inode number
+ * @new: %1 => added since the last commit, otherwise %0
+ */
+struct ubifs_orphan {
+	struct rb_node rb;
+	struct list_head list;
+	struct list_head new_list;
+	struct ubifs_orphan *cnext;
+	struct ubifs_orphan *dnext;
+	ino_t inum;
+	int new;
+};
+
+/**
+ * struct ubifs_mount_opts - UBIFS-specific mount options information.
+ * @unmount_mode: selected unmount mode (%0 default, %1 normal, %2 fast)
+ */
+struct ubifs_mount_opts {
+	unsigned int unmount_mode:2;
+};
+
+/**
+ * struct ubifs_info - UBIFS file-system description data structure
+ * (per-superblock).
+ * @vfs_sb: VFS @struct super_block object
+ * @bdi: backing device info object to make VFS happy and disable readahead
+ *
+ * @highest_inum: highest used inode number
+ * @vfs_gen: VFS inode generation counter
+ * @max_sqnum: current global sequence number
+ * @cmt_no: commit number (last successfully completed commit)
+ * @cnt_lock: protects @highest_inum, @vfs_gen, and @max_sqnum counters
+ * @fmt_version: UBIFS on-flash format version
+ * @uuid: UUID from super block
+ *
+ * @lhead_lnum: log head logical eraseblock number
+ * @lhead_offs: log head offset
+ * @ltail_lnum: log tail logical eraseblock number (offset is always 0)
+ * @log_mutex: protects the log, @lhead_lnum, @lhead_offs, @ltail_lnum, and
+ *             @bud_bytes
+ * @min_log_bytes: minimum required number of bytes in the log
+ * @cmt_bud_bytes: used during commit to temporarily amount of bytes in
+ *                 committed buds
+ *
+ * @buds: tree of all buds indexed by bud LEB number
+ * @bud_bytes: how many bytes of flash is used by buds
+ * @buds_lock: protects the @buds tree, @bud_bytes, and per-journal head bud
+ *             lists
+ * @jhead_cnt: count of journal heads
+ * @jheads: journal heads (head zero is base head)
+ * @max_bud_bytes: maximum number of bytes allowed in buds
+ * @bg_bud_bytes: number of bud bytes when background commit is initiated
+ * @old_buds: buds to be released after commit ends
+ * @max_bud_cnt: maximum number of buds
+ *
+ * @commit_sem: synchronizes committer with other processes
+ * @cmt_state: commit state
+ * @cs_lock: commit state lock
+ * @cmt_wq: wait queue to sleep on if the log is full and a commit is running
+ * @fast_unmount: do not run journal commit before un-mounting
+ * @big_lpt: flag that LPT is too big to write whole during commit
+ * @check_lpt_free: flag that indicates LPT GC may be needed
+ * @nospace: non-zero if the file-system does not have flash space (used as
+ *           optimization)
+ * @nospace_rp: the same as @nospace, but additionally means that even reserved
+ *              pool is full
+ *
+ * @tnc_mutex: protects the Tree Node Cache (TNC), @zroot, @cnext, @enext, and
+ *             @calc_idx_sz
+ * @zroot: zbranch which points to the root index node and znode
+ * @cnext: next znode to commit
+ * @enext: next znode to commit to empty space
+ * @gap_lebs: array of LEBs used by the in-gaps commit method
+ * @cbuf: commit buffer
+ * @ileb_buf: buffer for commit in-the-gaps method
+ * @ileb_len: length of data in ileb_buf
+ * @ihead_lnum: LEB number of index head
+ * @ihead_offs: offset of index head
+ * @ilebs: pre-allocated index LEBs
+ * @ileb_cnt: number of pre-allocated index LEBs
+ * @ileb_nxt: next pre-allocated index LEBs
+ * @old_idx: tree of index nodes obsoleted since the last commit start
+ * @bottom_up_buf: a buffer which is used by 'dirty_cow_bottom_up()' in tnc.c
+ * @new_ihead_lnum: used by debugging to check ihead_lnum
+ * @new_ihead_offs: used by debugging to check ihead_offs
+ *
+ * @mst_node: master node
+ * @mst_offs: offset of valid master node
+ * @mst_mutex: protects the master node area, @mst_node, and @mst_offs
+ *
+ * @log_lebs: number of logical eraseblocks in the log
+ * @log_bytes: log size in bytes
+ * @log_last: last LEB of the log
+ * @lpt_lebs: number of LEBs used for lprops table
+ * @lpt_first: first LEB of the lprops table area
+ * @lpt_last: last LEB of the lprops table area
+ * @orph_lebs: number of LEBs used for the orphan area
+ * @orph_first: first LEB of the orphan area
+ * @orph_last: last LEB of the orphan area
+ * @main_lebs: count of LEBs in the main area
+ * @main_first: first LEB of the main area
+ * @main_bytes: main area size in bytes
+ * @default_compr: default compression algorithm (%UBIFS_COMPR_LZO, etc)
+ *
+ * @key_hash_type: type of the key hash
+ * @key_hash: direntry key hash function
+ * @key_fmt: key format
+ * @key_len: key length
+ * @fanout: fanout of the index tree (number of links per indexing node)
+ *
+ * @min_io_size: minimal input/output unit size
+ * @min_io_shift: number of bits in @min_io_size minus one
+ * @leb_size: logical eraseblock size in bytes
+ * @half_leb_size: half LEB size
+ * @leb_cnt: count of logical eraseblocks
+ * @max_leb_cnt: maximum count of logical eraseblocks
+ * @old_leb_cnt: count of logical eraseblocks before re-size
+ * @ro_media: the underlying UBI volume is read-only
+ *
+ * @dirty_pg_cnt: number of dirty pages (not used)
+ * @dirty_zn_cnt: number of dirty znodes
+ * @clean_zn_cnt: number of clean znodes
+ *
+ * @budg_idx_growth: amount of bytes budgeted for index growth
+ * @budg_data_growth: amount of bytes budgeted for cached data
+ * @budg_dd_growth: amount of bytes budgeted for cached data that will make
+ *                  other data dirty
+ * @budg_uncommitted_idx: amount of bytes were budgeted for growth of the index,
+ *                        but which still have to be taken into account because
+ *                        the index has not been committed so far
+ * @space_lock: protects @budg_idx_growth, @budg_data_growth, @budg_dd_growth,
+ *              @budg_uncommited_idx, @min_idx_lebs, @old_idx_sz, and @lst;
+ * @min_idx_lebs: minimum number of LEBs required for the index
+ * @old_idx_sz: size of index on flash
+ * @calc_idx_sz: temporary variable which is used to calculate new index size
+ *               (contains accurate new index size at end of TNC commit start)
+ * @lst: lprops statistics
+ *
+ * @page_budget: budget for a page
+ * @inode_budget: budget for an inode
+ * @dent_budget: budget for a directory entry
+ *
+ * @ref_node_alsz: size of the LEB reference node aligned to the min. flash
+ * I/O unit
+ * @mst_node_alsz: master node aligned size
+ * @min_idx_node_sz: minimum indexing node aligned on 8-bytes boundary
+ * @max_idx_node_sz: maximum indexing node aligned on 8-bytes boundary
+ * @max_inode_sz: maximum possible inode size in bytes
+ * @max_znode_sz: size of znode in bytes
+ * @dead_wm: LEB dead space watermark
+ * @dark_wm: LEB dark space watermark
+ * @block_cnt: count of 4KiB blocks on the FS
+ *
+ * @ranges: UBIFS node length ranges
+ * @ubi: UBI volume descriptor
+ * @di: UBI device information
+ * @vi: UBI volume information
+ *
+ * @orph_tree: rb-tree of orphan inode numbers
+ * @orph_list: list of orphan inode numbers in order added
+ * @orph_new: list of orphan inode numbers added since last commit
+ * @orph_cnext: next orphan to commit
+ * @orph_dnext: next orphan to delete
+ * @orphan_lock: lock for orph_tree and orph_new
+ * @orph_buf: buffer for orphan nodes
+ * @new_orphans: number of orphans since last commit
+ * @cmt_orphans: number of orphans being committed
+ * @tot_orphans: number of orphans in the rb_tree
+ * @max_orphans: maximum number of orphans allowed
+ * @ohead_lnum: orphan head LEB number
+ * @ohead_offs: orphan head offset
+ * @no_orphs: non-zero if there are no orphans
+ *
+ * @bgt: UBIFS background thread
+ * @bgt_name: background thread name
+ * @need_bgt: if background thread should run
+ * @need_wbuf_sync: if write-buffers have to be synchronized
+ *
+ * @gc_lnum: LEB number used for garbage collection
+ * @sbuf: a buffer of LEB size used by GC and replay for scanning
+ * @idx_gc: list of index LEBs that have been garbage collected
+ * @idx_gc_cnt: number of elements on the idx_gc list
+ *
+ * @infos_list: links all 'ubifs_info' objects
+ * @umount_mutex: serializes shrinker and un-mount
+ * @shrinker_run_no: shrinker run number
+ *
+ * @space_bits: number of bits needed to record free or dirty space
+ * @lpt_lnum_bits: number of bits needed to record a LEB number in the LPT
+ * @lpt_offs_bits: number of bits needed to record an offset in the LPT
+ * @lpt_spc_bits: number of bits needed to space in the LPT
+ * @pcnt_bits: number of bits needed to record pnode or nnode number
+ * @lnum_bits: number of bits needed to record LEB number
+ * @nnode_sz: size of on-flash nnode
+ * @pnode_sz: size of on-flash pnode
+ * @ltab_sz: size of on-flash LPT lprops table
+ * @lsave_sz: size of on-flash LPT save table
+ * @pnode_cnt: number of pnodes
+ * @nnode_cnt: number of nnodes
+ * @lpt_hght: height of the LPT
+ * @pnodes_have: number of pnodes in memory
+ *
+ * @lp_mutex: protects lprops table and all the other lprops-related fields
+ * @lpt_lnum: LEB number of the root nnode of the LPT
+ * @lpt_offs: offset of the root nnode of the LPT
+ * @nhead_lnum: LEB number of LPT head
+ * @nhead_offs: offset of LPT head
+ * @lpt_drty_flgs: dirty flags for LPT special nodes e.g. ltab
+ * @dirty_nn_cnt: number of dirty nnodes
+ * @dirty_pn_cnt: number of dirty pnodes
+ * @lpt_sz: LPT size
+ * @lpt_nod_buf: buffer for an on-flash nnode or pnode
+ * @lpt_buf: buffer of LEB size used by LPT
+ * @nroot: address in memory of the root nnode of the LPT
+ * @lpt_cnext: next LPT node to commit
+ * @lpt_heap: array of heaps of categorized lprops
+ * @dirty_idx: a (reverse sorted) copy of the LPROPS_DIRTY_IDX heap as at
+ *             previous commit start
+ * @uncat_list: list of un-categorized LEBs
+ * @empty_list: list of empty LEBs
+ * @freeable_list: list of freeable non-index LEBs (free + dirty == leb_size)
+ * @frdi_idx_list: list of freeable index LEBs (free + dirty == leb_size)
+ * @freeable_cnt: number of freeable LEBs in @freeable_list
+ *
+ * @ltab_lnum: LEB number of LPT's own lprops table
+ * @ltab_offs: offset of LPT's own lprops table
+ * @ltab: LPT's own lprops table
+ * @ltab_cmt: LPT's own lprops table (commit copy)
+ * @lsave_cnt: number of LEB numbers in LPT's save table
+ * @lsave_lnum: LEB number of LPT's save table
+ * @lsave_offs: offset of LPT's save table
+ * @lsave: LPT's save table
+ * @lscan_lnum: LEB number of last LPT scan
+ *
+ * @rp_size: size of the reserved pool in bytes
+ * @report_rp_size: size of the reserved pool reported to user-space
+ * @rp_uid: reserved pool user ID
+ * @rp_gid: reserved pool group ID
+ *
+ * @empty: if the UBI device is empty
+ * @replay_tree: temporary tree used during journal replay
+ * @replay_list: temporary list used during journal replay
+ * @replay_buds: list of buds to replay
+ * @cs_sqnum: sequence number of first node in the log (commit start node)
+ * @replay_sqnum: sequence number of node currently being replayed
+ * @need_recovery: file-system needs recovery
+ * @replaying: set to %1 during journal replay
+ * @unclean_leb_list: LEBs to recover when mounting ro to rw
+ * @rcvrd_mst_node: recovered master node to write when mounting ro to rw
+ * @size_tree: inode size information for recovery
+ * @remounting_rw: set while remounting from ro to rw (sb flags have MS_RDONLY)
+ * @mount_opts: UBIFS-specific mount options
+ *
+ * @dbg_buf: a buffer of LEB size used for debugging purposes
+ * @old_zroot: old index root - used by 'dbg_check_old_index()'
+ * @old_zroot_level: old index root level - used by 'dbg_check_old_index()'
+ * @old_zroot_sqnum: old index root sqnum - used by 'dbg_check_old_index()'
+ * @failure_mode: failure mode for recovery testing
+ * @fail_delay: 0=>don't delay, 1=>delay a time, 2=>delay a number of calls
+ * @fail_timeout: time in jiffies when delay of failure mode expires
+ * @fail_cnt: current number of calls to failure mode I/O functions
+ * @fail_cnt_max: number of calls by which to delay failure mode
+ */
+struct ubifs_info {
+	struct super_block *vfs_sb;
+	struct backing_dev_info bdi;
+
+	ino_t highest_inum;
+	unsigned int vfs_gen;
+	unsigned long long max_sqnum;
+	unsigned long long cmt_no;
+	spinlock_t cnt_lock;
+	int fmt_version;
+	unsigned char uuid[16];
+
+	int lhead_lnum;
+	int lhead_offs;
+	int ltail_lnum;
+	struct mutex log_mutex;
+	int min_log_bytes;
+	long long cmt_bud_bytes;
+
+	struct rb_root buds;
+	long long bud_bytes;
+	spinlock_t buds_lock;
+	int jhead_cnt;
+	struct ubifs_jhead *jheads;
+	long long max_bud_bytes;
+	long long bg_bud_bytes;
+	struct list_head old_buds;
+	int max_bud_cnt;
+
+	struct rw_semaphore commit_sem;
+	int cmt_state;
+	spinlock_t cs_lock;
+	wait_queue_head_t cmt_wq;
+	unsigned int fast_unmount:1;
+	unsigned int big_lpt:1;
+	unsigned int check_lpt_free:1;
+	unsigned int nospace:1;
+	unsigned int nospace_rp:1;
+
+	struct mutex tnc_mutex;
+	struct ubifs_zbranch zroot;
+	struct ubifs_znode *cnext;
+	struct ubifs_znode *enext;
+	int *gap_lebs;
+	void *cbuf;
+	void *ileb_buf;
+	int ileb_len;
+	int ihead_lnum;
+	int ihead_offs;
+	int *ilebs;
+	int ileb_cnt;
+	int ileb_nxt;
+	struct rb_root old_idx;
+	int *bottom_up_buf;
+#ifdef CONFIG_UBIFS_FS_DEBUG
+	int new_ihead_lnum;
+	int new_ihead_offs;
+#endif
+
+	struct ubifs_mst_node *mst_node;
+	int mst_offs;
+	struct mutex mst_mutex;
+
+	int log_lebs;
+	long long log_bytes;
+	int log_last;
+	int lpt_lebs;
+	int lpt_first;
+	int lpt_last;
+	int orph_lebs;
+	int orph_first;
+	int orph_last;
+	int main_lebs;
+	int main_first;
+	long long main_bytes;
+	int default_compr;
+
+	uint8_t key_hash_type;
+	uint32_t (*key_hash)(const char *str, int len);
+	int key_fmt;
+	int key_len;
+	int fanout;
+
+	int min_io_size;
+	int min_io_shift;
+	int leb_size;
+	int half_leb_size;
+	int leb_cnt;
+	int max_leb_cnt;
+	int old_leb_cnt;
+	int ro_media;
+
+	atomic_long_t dirty_pg_cnt;
+	atomic_long_t dirty_zn_cnt;
+	atomic_long_t clean_zn_cnt;
+
+	long long budg_idx_growth;
+	long long budg_data_growth;
+	long long budg_dd_growth;
+	long long budg_uncommitted_idx;
+	spinlock_t space_lock;
+	int min_idx_lebs;
+	unsigned long long old_idx_sz;
+	unsigned long long calc_idx_sz;
+	struct ubifs_lp_stats lst;
+
+	int page_budget;
+	int inode_budget;
+	int dent_budget;
+
+	int ref_node_alsz;
+	int mst_node_alsz;
+	int min_idx_node_sz;
+	int max_idx_node_sz;
+	long long max_inode_sz;
+	int max_znode_sz;
+	int dead_wm;
+	int dark_wm;
+	int block_cnt;
+
+	struct ubifs_node_range ranges[UBIFS_NODE_TYPES_CNT];
+	struct ubi_volume_desc *ubi;
+	struct ubi_device_info di;
+	struct ubi_volume_info vi;
+
+	struct rb_root orph_tree;
+	struct list_head orph_list;
+	struct list_head orph_new;
+	struct ubifs_orphan *orph_cnext;
+	struct ubifs_orphan *orph_dnext;
+	spinlock_t orphan_lock;
+	void *orph_buf;
+	int new_orphans;
+	int cmt_orphans;
+	int tot_orphans;
+	int max_orphans;
+	int ohead_lnum;
+	int ohead_offs;
+	int no_orphs;
+
+	struct task_struct *bgt;
+	char bgt_name[sizeof(BGT_NAME_PATTERN) + 9];
+	int need_bgt;
+	int need_wbuf_sync;
+
+	int gc_lnum;
+	void *sbuf;
+	struct list_head idx_gc;
+	int idx_gc_cnt;
+
+	struct list_head infos_list;
+	struct mutex umount_mutex;
+	unsigned int shrinker_run_no;
+
+	int space_bits;
+	int lpt_lnum_bits;
+	int lpt_offs_bits;
+	int lpt_spc_bits;
+	int pcnt_bits;
+	int lnum_bits;
+	int nnode_sz;
+	int pnode_sz;
+	int ltab_sz;
+	int lsave_sz;
+	int pnode_cnt;
+	int nnode_cnt;
+	int lpt_hght;
+	int pnodes_have;
+
+	struct mutex lp_mutex;
+	int lpt_lnum;
+	int lpt_offs;
+	int nhead_lnum;
+	int nhead_offs;
+	int lpt_drty_flgs;
+	int dirty_nn_cnt;
+	int dirty_pn_cnt;
+	long long lpt_sz;
+	void *lpt_nod_buf;
+	void *lpt_buf;
+	struct ubifs_nnode *nroot;
+	struct ubifs_cnode *lpt_cnext;
+	struct ubifs_lpt_heap lpt_heap[LPROPS_HEAP_CNT];
+	struct ubifs_lpt_heap dirty_idx;
+	struct list_head uncat_list;
+	struct list_head empty_list;
+	struct list_head freeable_list;
+	struct list_head frdi_idx_list;
+	int freeable_cnt;
+
+	int ltab_lnum;
+	int ltab_offs;
+	struct ubifs_lpt_lprops *ltab;
+	struct ubifs_lpt_lprops *ltab_cmt;
+	int lsave_cnt;
+	int lsave_lnum;
+	int lsave_offs;
+	int *lsave;
+	int lscan_lnum;
+
+	long long rp_size;
+	long long report_rp_size;
+	uid_t rp_uid;
+	gid_t rp_gid;
+
+	/* The below fields are used only during mounting and re-mounting */
+	int empty;
+	struct rb_root replay_tree;
+	struct list_head replay_list;
+	struct list_head replay_buds;
+	unsigned long long cs_sqnum;
+	unsigned long long replay_sqnum;
+	int need_recovery;
+	int replaying;
+	struct list_head unclean_leb_list;
+	struct ubifs_mst_node *rcvrd_mst_node;
+	struct rb_root size_tree;
+	int remounting_rw;
+	struct ubifs_mount_opts mount_opts;
+
+#ifdef CONFIG_UBIFS_FS_DEBUG
+	void *dbg_buf;
+	struct ubifs_zbranch old_zroot;
+	int old_zroot_level;
+	unsigned long long old_zroot_sqnum;
+	int failure_mode;
+	int fail_delay;
+	unsigned long fail_timeout;
+	unsigned int fail_cnt;
+	unsigned int fail_cnt_max;
+#endif
+};
+
+extern struct list_head ubifs_infos;
+extern spinlock_t ubifs_infos_lock;
+extern atomic_long_t ubifs_clean_zn_cnt;
+extern struct kmem_cache *ubifs_inode_slab;
+extern struct super_operations ubifs_super_operations;
+extern struct address_space_operations ubifs_file_address_operations;
+extern struct file_operations ubifs_file_operations;
+extern struct inode_operations ubifs_file_inode_operations;
+extern struct file_operations ubifs_dir_operations;
+extern struct inode_operations ubifs_dir_inode_operations;
+extern struct inode_operations ubifs_symlink_inode_operations;
+extern struct backing_dev_info ubifs_backing_dev_info;
+extern struct ubifs_compressor *ubifs_compressors[UBIFS_COMPR_TYPES_CNT];
+
+/* io.c */
+int ubifs_wbuf_write_nolock(struct ubifs_wbuf *wbuf, void *buf, int len);
+int ubifs_wbuf_seek_nolock(struct ubifs_wbuf *wbuf, int lnum, int offs,
+			   int dtype);
+int ubifs_wbuf_init(struct ubifs_info *c, struct ubifs_wbuf *wbuf);
+int ubifs_read_node(const struct ubifs_info *c, void *buf, int type, int len,
+		    int lnum, int offs);
+int ubifs_read_node_wbuf(struct ubifs_wbuf *wbuf, void *buf, int type, int len,
+			 int lnum, int offs);
+int ubifs_write_node(struct ubifs_info *c, void *node, int len, int lnum,
+		     int offs, int dtype);
+int ubifs_check_node(const struct ubifs_info *c, const void *buf, int lnum,
+		     int offs, int quiet);
+void ubifs_prepare_node(struct ubifs_info *c, void *buf, int len, int pad);
+void ubifs_prep_grp_node(struct ubifs_info *c, void *node, int len, int last);
+int ubifs_io_init(struct ubifs_info *c);
+void ubifs_pad(const struct ubifs_info *c, void *buf, int pad);
+int ubifs_wbuf_sync_nolock(struct ubifs_wbuf *wbuf);
+int ubifs_bg_wbufs_sync(struct ubifs_info *c);
+void ubifs_wbuf_add_ino_nolock(struct ubifs_wbuf *wbuf, ino_t inum);
+int ubifs_sync_wbufs_by_inode(struct ubifs_info *c, struct inode *inode);
+
+/* scan.c */
+struct ubifs_scan_leb *ubifs_scan(const struct ubifs_info *c, int lnum,
+				  int offs, void *sbuf);
+void ubifs_scan_destroy(struct ubifs_scan_leb *sleb);
+int ubifs_scan_a_node(const struct ubifs_info *c, void *buf, int len, int lnum,
+		      int offs, int quiet);
+struct ubifs_scan_leb *ubifs_start_scan(const struct ubifs_info *c, int lnum,
+					int offs, void *sbuf);
+void ubifs_end_scan(const struct ubifs_info *c, struct ubifs_scan_leb *sleb,
+		    int lnum, int offs);
+int ubifs_add_snod(const struct ubifs_info *c, struct ubifs_scan_leb *sleb,
+		   void *buf, int offs);
+void ubifs_scanned_corruption(const struct ubifs_info *c, int lnum, int offs,
+			      void *buf);
+
+/* log.c */
+void ubifs_add_bud(struct ubifs_info *c, struct ubifs_bud *bud);
+void ubifs_create_buds_lists(struct ubifs_info *c);
+int ubifs_add_bud_to_log(struct ubifs_info *c, int jhead, int lnum, int offs);
+struct ubifs_bud *ubifs_search_bud(struct ubifs_info *c, int lnum);
+struct ubifs_wbuf *ubifs_get_wbuf(struct ubifs_info *c, int lnum);
+int ubifs_log_start_commit(struct ubifs_info *c, int *ltail_lnum);
+int ubifs_log_end_commit(struct ubifs_info *c, int new_ltail_lnum);
+int ubifs_log_post_commit(struct ubifs_info *c, int old_ltail_lnum);
+int ubifs_consolidate_log(struct ubifs_info *c);
+
+/* journal.c */
+int ubifs_jnl_update(struct ubifs_info *c, const struct inode *dir,
+		     const struct qstr *nm, const struct inode *inode,
+		     int deletion, int xent);
+int ubifs_jnl_write_data(struct ubifs_info *c, const struct inode *inode,
+			 const union ubifs_key *key, const void *buf, int len);
+int ubifs_jnl_write_inode(struct ubifs_info *c, const struct inode *inode,
+			  int last_reference);
+int ubifs_jnl_rename(struct ubifs_info *c, const struct inode *old_dir,
+		     const struct dentry *old_dentry,
+		     const struct inode *new_dir,
+		     const struct dentry *new_dentry, int sync);
+int ubifs_jnl_truncate(struct ubifs_info *c, const struct inode *inode,
+		       loff_t old_size, loff_t new_size);
+int ubifs_jnl_delete_xattr(struct ubifs_info *c, const struct inode *host,
+			   const struct inode *inode, const struct qstr *nm);
+int ubifs_jnl_change_xattr(struct ubifs_info *c, const struct inode *inode1,
+			   const struct inode *inode2);
+
+/* budget.c */
+int ubifs_budget_space(struct ubifs_info *c, struct ubifs_budget_req *req);
+void ubifs_release_budget(struct ubifs_info *c, struct ubifs_budget_req *req);
+void ubifs_release_dirty_inode_budget(struct ubifs_info *c,
+				      struct ubifs_inode *ui);
+int ubifs_budget_inode_op(struct ubifs_info *c, struct inode *inode,
+			  struct ubifs_budget_req *req);
+void ubifs_release_ino_dirty(struct ubifs_info *c, struct inode *inode,
+				struct ubifs_budget_req *req);
+void ubifs_cancel_ino_op(struct ubifs_info *c, struct inode *inode,
+			 struct ubifs_budget_req *req);
+long long ubifs_budg_get_free_space(struct ubifs_info *c);
+int ubifs_calc_min_idx_lebs(struct ubifs_info *c);
+void ubifs_convert_page_budget(struct ubifs_info *c);
+long long ubifs_calc_available(const struct ubifs_info *c, int min_idx_lebs);
+
+/* find.c */
+int ubifs_find_free_space(struct ubifs_info *c, int min_space, int *free,
+			  int squeeze);
+int ubifs_find_free_leb_for_idx(struct ubifs_info *c);
+int ubifs_find_dirty_leb(struct ubifs_info *c, struct ubifs_lprops *ret_lp,
+			 int min_space, int pick_free);
+int ubifs_find_dirty_idx_leb(struct ubifs_info *c);
+int ubifs_save_dirty_idx_lnums(struct ubifs_info *c);
+
+/* tnc.c */
+int ubifs_lookup_level0(struct ubifs_info *c, const union ubifs_key *key,
+			struct ubifs_znode **zn, int *n);
+int ubifs_tnc_lookup(struct ubifs_info *c, const union ubifs_key *key,
+		     void *node);
+int ubifs_tnc_lookup_nm(struct ubifs_info *c, const union ubifs_key *key,
+			void *node, const struct qstr *nm);
+int ubifs_tnc_locate(struct ubifs_info *c, const union ubifs_key *key,
+		     void *node, int *lnum, int *offs);
+int ubifs_tnc_add(struct ubifs_info *c, const union ubifs_key *key, int lnum,
+		  int offs, int len);
+int ubifs_tnc_replace(struct ubifs_info *c, const union ubifs_key *key,
+		      int old_lnum, int old_offs, int lnum, int offs, int len);
+int ubifs_tnc_add_nm(struct ubifs_info *c, const union ubifs_key *key,
+		     int lnum, int offs, int len, const struct qstr *nm);
+int ubifs_tnc_remove(struct ubifs_info *c, const union ubifs_key *key);
+int ubifs_tnc_remove_nm(struct ubifs_info *c, const union ubifs_key *key,
+			const struct qstr *nm);
+int ubifs_tnc_remove_range(struct ubifs_info *c, union ubifs_key *from_key,
+			   union ubifs_key *to_key);
+int ubifs_tnc_remove_ino(struct ubifs_info *c, ino_t inum);
+struct ubifs_dent_node *ubifs_tnc_next_ent(struct ubifs_info *c,
+					   union ubifs_key *key,
+					   const struct qstr *nm);
+void ubifs_tnc_close(struct ubifs_info *c);
+int ubifs_tnc_has_node(struct ubifs_info *c, union ubifs_key *key, int level,
+		       int lnum, int offs, int is_idx);
+int ubifs_dirty_idx_node(struct ubifs_info *c, union ubifs_key *key, int level,
+			 int lnum, int offs);
+/* Shared by tnc.c for tnc_commit.c */
+void destroy_old_idx(struct ubifs_info *c);
+int is_idx_node_in_tnc(struct ubifs_info *c, union ubifs_key *key, int level,
+		       int lnum, int offs);
+int insert_old_idx_znode(struct ubifs_info *c, struct ubifs_znode *znode);
+
+/* tnc_misc.c */
+struct ubifs_znode *ubifs_tnc_levelorder_next(struct ubifs_znode *zr,
+					      struct ubifs_znode *znode);
+int ubifs_search_zbranch(const struct ubifs_info *c,
+			 const struct ubifs_znode *znode,
+			 const union ubifs_key *key, int *n);
+struct ubifs_znode *ubifs_tnc_postorder_first(struct ubifs_znode *znode);
+struct ubifs_znode *ubifs_tnc_postorder_next(struct ubifs_znode *znode);
+long ubifs_destroy_tnc_subtree(struct ubifs_znode *zr);
+struct ubifs_znode *ubifs_load_znode(struct ubifs_info *c,
+				     struct ubifs_zbranch *zbr,
+				     struct ubifs_znode *parent, int iip);
+int ubifs_tnc_read_node(struct ubifs_info *c, struct ubifs_zbranch *zbr,
+			void *node);
+
+/* tnc_commit.c */
+int ubifs_tnc_start_commit(struct ubifs_info *c, struct ubifs_zbranch *zroot);
+int ubifs_tnc_end_commit(struct ubifs_info *c);
+
+/* shrinker.c */
+int ubifs_shrinker(int nr_to_scan, gfp_t gfp_mask);
+
+/* commit.c */
+int ubifs_bg_thread(void *info);
+void ubifs_commit_required(struct ubifs_info *c);
+void ubifs_request_bg_commit(struct ubifs_info *c);
+int ubifs_run_commit(struct ubifs_info *c);
+void ubifs_recovery_commit(struct ubifs_info *c);
+int ubifs_gc_should_commit(struct ubifs_info *c);
+void ubifs_wait_for_commit(struct ubifs_info *c);
+
+/* master.c */
+int ubifs_read_master(struct ubifs_info *c);
+int ubifs_write_master(struct ubifs_info *c);
+
+/* sb.c */
+int ubifs_read_superblock(struct ubifs_info *c);
+struct ubifs_sb_node *ubifs_read_sb_node(struct ubifs_info *c);
+int ubifs_write_sb_node(struct ubifs_info *c, struct ubifs_sb_node *sup);
+
+/* replay.c */
+int ubifs_validate_entry(struct ubifs_info *c,
+			 const struct ubifs_dent_node *dent);
+int ubifs_replay_journal(struct ubifs_info *c);
+
+/* gc.c */
+int ubifs_garbage_collect(struct ubifs_info *c, int anyway);
+int ubifs_gc_start_commit(struct ubifs_info *c);
+int ubifs_gc_end_commit(struct ubifs_info *c);
+void ubifs_destroy_idx_gc(struct ubifs_info *c);
+int ubifs_get_idx_gc_leb(struct ubifs_info *c);
+int ubifs_garbage_collect_leb(struct ubifs_info *c, struct ubifs_lprops *lp);
+
+/* orphan.c */
+int ubifs_add_orphan(struct ubifs_info *c, ino_t inum);
+void ubifs_delete_orphan(struct ubifs_info *c, ino_t inum);
+int ubifs_orphan_start_commit(struct ubifs_info *c);
+int ubifs_orphan_end_commit(struct ubifs_info *c);
+int ubifs_mount_orphans(struct ubifs_info *c, int unclean, int read_only);
+
+/* lpt.c */
+int ubifs_calc_lpt_geom(struct ubifs_info *c);
+int ubifs_create_dflt_lpt(struct ubifs_info *c, int *main_lebs, int lpt_first,
+			  int *lpt_lebs, int *big_lpt);
+int ubifs_lpt_init(struct ubifs_info *c, int rd, int wr);
+struct ubifs_lprops *ubifs_lpt_lookup(struct ubifs_info *c, int lnum);
+struct ubifs_lprops *ubifs_lpt_lookup_dirty(struct ubifs_info *c, int lnum);
+int ubifs_lpt_scan_nolock(struct ubifs_info *c, int start_lnum, int end_lnum,
+			  ubifs_lpt_scan_callback scan_cb, void *data);
+
+/* Shared by lpt.c for lpt_commit.c */
+void ubifs_pack_lsave(struct ubifs_info *c, void *buf, int *lsave);
+void ubifs_pack_ltab(struct ubifs_info *c, void *buf,
+		     struct ubifs_lpt_lprops *ltab);
+void ubifs_pack_pnode(struct ubifs_info *c, void *buf,
+		      struct ubifs_pnode *pnode);
+void ubifs_pack_nnode(struct ubifs_info *c, void *buf,
+		      struct ubifs_nnode *nnode);
+struct ubifs_pnode *ubifs_get_pnode(struct ubifs_info *c,
+				    struct ubifs_nnode *parent, int iip);
+struct ubifs_nnode *ubifs_get_nnode(struct ubifs_info *c,
+				    struct ubifs_nnode *parent, int iip);
+int ubifs_read_nnode(struct ubifs_info *c, struct ubifs_nnode *parent, int iip);
+void ubifs_add_lpt_dirt(struct ubifs_info *c, int lnum, int dirty);
+void ubifs_add_nnode_dirt(struct ubifs_info *c, struct ubifs_nnode *nnode);
+uint32_t ubifs_unpack_bits(uint8_t **addr, int *pos, int nrbits);
+struct ubifs_nnode *ubifs_first_nnode(struct ubifs_info *c, int *hght);
+
+/* lpt_commit.c */
+int ubifs_lpt_start_commit(struct ubifs_info *c);
+int ubifs_lpt_end_commit(struct ubifs_info *c);
+int ubifs_lpt_post_commit(struct ubifs_info *c);
+void ubifs_lpt_free(struct ubifs_info *c, int wr_only);
+
+/* lprops.c */
+void ubifs_get_lprops(struct ubifs_info *c);
+const struct ubifs_lprops *ubifs_change_lp(struct ubifs_info *c,
+					   const struct ubifs_lprops *lp,
+					   int free, int dirty, int flags,
+					   int idx_gc_cnt);
+void ubifs_release_lprops(struct ubifs_info *c);
+void ubifs_get_lp_stats(struct ubifs_info *c, struct ubifs_lp_stats *stats);
+void ubifs_add_to_cat(struct ubifs_info *c, struct ubifs_lprops *lprops,
+		      int cat);
+void ubifs_replace_cat(struct ubifs_info *c, struct ubifs_lprops *old_lprops,
+		       struct ubifs_lprops *new_lprops);
+void ubifs_ensure_cat(struct ubifs_info *c, struct ubifs_lprops *lprops);
+int ubifs_categorize_lprops(const struct ubifs_info *c,
+			    const struct ubifs_lprops *lprops);
+int ubifs_change_one_lp(struct ubifs_info *c, int lnum, int free, int dirty,
+			int flags_set, int flags_clean, int idx_gc_cnt);
+int ubifs_update_one_lp(struct ubifs_info *c, int lnum, int free, int dirty,
+			int flags_set, int flags_clean);
+int ubifs_read_one_lp(struct ubifs_info *c, int lnum, struct ubifs_lprops *lp);
+const struct ubifs_lprops *ubifs_fast_find_free(struct ubifs_info *c);
+const struct ubifs_lprops *ubifs_fast_find_empty(struct ubifs_info *c);
+const struct ubifs_lprops *ubifs_fast_find_freeable(struct ubifs_info *c);
+const struct ubifs_lprops *ubifs_fast_find_frdi_idx(struct ubifs_info *c);
+
+/* file.c */
+int ubifs_fsync(struct file *file, struct dentry *dentry, int datasync);
+int ubifs_setattr(struct dentry *dentry, struct iattr *attr);
+
+/* dir.c */
+struct inode *ubifs_new_inode(struct ubifs_info *c, const struct inode *dir,
+			      int mode);
+int ubifs_getattr(struct vfsmount *mnt, struct dentry *dentry,
+		  struct kstat *stat);
+
+/* xattr.c */
+int ubifs_setxattr(struct dentry *dentry, const char *name,
+		   const void *value, size_t size, int flags);
+ssize_t ubifs_getxattr(struct dentry *dentry, const char *name, void *buf,
+		       size_t size);
+ssize_t ubifs_listxattr(struct dentry *dentry, char *buffer, size_t size);
+int ubifs_removexattr(struct dentry *dentry, const char *name);
+
+/* super.c */
+struct inode *ubifs_iget(struct super_block *sb, unsigned long inum);
+
+/* recovery.c */
+int ubifs_recover_master_node(struct ubifs_info *c);
+int ubifs_write_rcvrd_mst_node(struct ubifs_info *c);
+struct ubifs_scan_leb *ubifs_recover_leb(struct ubifs_info *c, int lnum,
+					 int offs, void *sbuf, int grouped);
+struct ubifs_scan_leb *ubifs_recover_log_leb(struct ubifs_info *c, int lnum,
+					     int offs, void *sbuf);
+int ubifs_recover_inl_heads(const struct ubifs_info *c, void *sbuf);
+int ubifs_clean_lebs(const struct ubifs_info *c, void *sbuf);
+int ubifs_rcvry_gc_commit(struct ubifs_info *c);
+int ubifs_recover_size_accum(struct ubifs_info *c, union ubifs_key *key,
+			     int deletion, loff_t new_size);
+int ubifs_recover_size(struct ubifs_info *c);
+void ubifs_destroy_size_tree(struct ubifs_info *c);
+
+/* ioctl.c */
+long ubifs_ioctl(struct file *file, unsigned int cmd, unsigned long arg);
+void ubifs_set_inode_flags(struct inode *inode);
+#ifdef CONFIG_COMPAT
+long ubifs_compat_ioctl(struct file *file, unsigned int cmd, unsigned long arg);
+#endif
+
+/* compressor.c */
+int __init ubifs_compressors_init(void);
+void __exit ubifs_compressors_exit(void);
+void ubifs_compress(const void *in_buf, int in_len, void *out_buf, int *out_len,
+		    int *compr_type);
+int ubifs_decompress(const void *buf, int len, void *out, int *out_len,
+		     int compr_type);
+
+#include "debug.h"
+#include "misc.h"
+#include "key.h"
+
+#endif /* !__UBIFS_H__ */
diff --git a/fs/ubifs/xattr.c b/fs/ubifs/xattr.c
new file mode 100644
index 00000000000..1388a078e1a
--- /dev/null
+++ b/fs/ubifs/xattr.c
@@ -0,0 +1,581 @@
+/*
+ * This file is part of UBIFS.
+ *
+ * Copyright (C) 2006-2008 Nokia Corporation.
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 as published by
+ * the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
+ * more details.
+ *
+ * You should have received a copy of the GNU General Public License along with
+ * this program; if not, write to the Free Software Foundation, Inc., 51
+ * Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
+ *
+ * Authors: Artem Bityutskiy (Битюцкий Артём)
+ *          Adrian Hunter
+ */
+
+/*
+ * This file implements UBIFS extended attributes support.
+ *
+ * Extended attributes are implemented as regular inodes with attached data,
+ * which limits extended attribute size to UBIFS block size (4KiB). Names of
+ * extended attributes are described by extended attribute entries (xentries),
+ * which are almost identical to directory entries, but have different key type.
+ *
+ * In other words, the situation with extended attributes is very similar to
+ * directories. Indeed, any inode (but of course not xattr inodes) may have a
+ * number of associated xentries, just like directory inodes have associated
+ * directory entries. Extended attribute entries store the name of the extended
+ * attribute, the host inode number, and the extended attribute inode number.
+ * Similarly, direntries store the name, the parent and the target inode
+ * numbers. Thus, most of the common UBIFS mechanisms may be re-used for
+ * extended attributes.
+ *
+ * The number of extended attributes is not limited, but there is Linux
+ * limitation on the maximum possible size of the list of all extended
+ * attributes associated with an inode (%XATTR_LIST_MAX), so UBIFS makes sure
+ * the sum of all extended attribute names of the inode does not exceed that
+ * limit.
+ *
+ * Extended attributes are synchronous, which means they are written to the
+ * flash media synchronously and there is no write-back for extended attribute
+ * inodes. The extended attribute values are not stored in compressed form on
+ * the media.
+ *
+ * Since extended attributes are represented by regular inodes, they are cached
+ * in the VFS inode cache. The xentries are cached in the LNC cache (see
+ * tnc.c).
+ *
+ * ACL support is not implemented.
+ */
+
+#include <linux/xattr.h>
+#include <linux/posix_acl_xattr.h>
+#include "ubifs.h"
+
+/*
+ * Limit the number of extended attributes per inode so that the total size
+ * (xattr_size) is guaranteeded to fit in an 'unsigned int'.
+ */
+#define MAX_XATTRS_PER_INODE 65535
+
+/*
+ * Extended attribute type constants.
+ *
+ * USER_XATTR: user extended attribute ("user.*")
+ * TRUSTED_XATTR: trusted extended attribute ("trusted.*)
+ * SECURITY_XATTR: security extended attribute ("security.*")
+ */
+enum {
+	USER_XATTR,
+	TRUSTED_XATTR,
+	SECURITY_XATTR,
+};
+
+static struct inode_operations none_inode_operations;
+static struct address_space_operations none_address_operations;
+static struct file_operations none_file_operations;
+
+/**
+ * create_xattr - create an extended attribute.
+ * @c: UBIFS file-system description object
+ * @host: host inode
+ * @nm: extended attribute name
+ * @value: extended attribute value
+ * @size: size of extended attribute value
+ *
+ * This is a helper function which creates an extended attribute of name @nm
+ * and value @value for inode @host. The host inode is also updated on flash
+ * because the ctime and extended attribute accounting data changes. This
+ * function returns zero in case of success and a negative error code in case
+ * of failure.
+ */
+static int create_xattr(struct ubifs_info *c, struct inode *host,
+			const struct qstr *nm, const void *value, int size)
+{
+	int err;
+	struct inode *inode;
+	struct ubifs_inode *ui, *host_ui = ubifs_inode(host);
+	struct ubifs_budget_req req = { .new_ino = 1, .new_dent = 1,
+					.new_ino_d = size, .dirtied_ino = 1,
+					.dirtied_ino_d = host_ui->data_len};
+
+	if (host_ui->xattr_cnt >= MAX_XATTRS_PER_INODE)
+		return -ENOSPC;
+	/*
+	 * Linux limits the maximum size of the extended attribute names list
+	 * to %XATTR_LIST_MAX. This means we should not allow creating more*
+	 * extended attributes if the name list becomes larger. This limitation
+	 * is artificial for UBIFS, though.
+	 */
+	if (host_ui->xattr_names + host_ui->xattr_cnt +
+					nm->len + 1 > XATTR_LIST_MAX)
+		return -ENOSPC;
+
+	err = ubifs_budget_space(c, &req);
+	if (err)
+		return err;
+
+	inode = ubifs_new_inode(c, host, S_IFREG | S_IRWXUGO);
+	if (IS_ERR(inode)) {
+		err = PTR_ERR(inode);
+		goto out_budg;
+	}
+
+	mutex_lock(&host_ui->ui_mutex);
+	/* Re-define all operations to be "nothing" */
+	inode->i_mapping->a_ops = &none_address_operations;
+	inode->i_op = &none_inode_operations;
+	inode->i_fop = &none_file_operations;
+
+	inode->i_flags |= S_SYNC | S_NOATIME | S_NOCMTIME | S_NOQUOTA;
+	ui = ubifs_inode(inode);
+	ui->xattr = 1;
+	ui->flags |= UBIFS_XATTR_FL;
+	ui->data = kmalloc(size, GFP_NOFS);
+	if (!ui->data) {
+		err = -ENOMEM;
+		goto out_unlock;
+	}
+
+	memcpy(ui->data, value, size);
+	host->i_ctime = ubifs_current_time(host);
+	host_ui->xattr_cnt += 1;
+	host_ui->xattr_size += CALC_DENT_SIZE(nm->len);
+	host_ui->xattr_size += CALC_XATTR_BYTES(size);
+	host_ui->xattr_names += nm->len;
+
+	/*
+	 * We do not use i_size_write() because nobody can race with us as we
+	 * are holding host @host->i_mutex - every xattr operation for this
+	 * inode is serialized by it.
+	 */
+	inode->i_size = ui->ui_size = size;
+	ui->data_len = size;
+	err = ubifs_jnl_update(c, host, nm, inode, 0, 1);
+	if (err)
+		goto out_cancel;
+	mutex_unlock(&host_ui->ui_mutex);
+
+	ubifs_release_budget(c, &req);
+	insert_inode_hash(inode);
+	iput(inode);
+	return 0;
+
+out_cancel:
+	host_ui->xattr_cnt -= 1;
+	host_ui->xattr_size -= CALC_DENT_SIZE(nm->len);
+	host_ui->xattr_size -= CALC_XATTR_BYTES(size);
+out_unlock:
+	mutex_unlock(&host_ui->ui_mutex);
+	make_bad_inode(inode);
+	iput(inode);
+out_budg:
+	ubifs_release_budget(c, &req);
+	return err;
+}
+
+/**
+ * change_xattr - change an extended attribute.
+ * @c: UBIFS file-system description object
+ * @host: host inode
+ * @inode: extended attribute inode
+ * @value: extended attribute value
+ * @size: size of extended attribute value
+ *
+ * This helper function changes the value of extended attribute @inode with new
+ * data from @value. Returns zero in case of success and a negative error code
+ * in case of failure.
+ */
+static int change_xattr(struct ubifs_info *c, struct inode *host,
+			struct inode *inode, const void *value, int size)
+{
+	int err;
+	struct ubifs_inode *host_ui = ubifs_inode(host);
+	struct ubifs_inode *ui = ubifs_inode(inode);
+	struct ubifs_budget_req req = { .dirtied_ino = 2,
+				.dirtied_ino_d = size + host_ui->data_len };
+
+	ubifs_assert(ui->data_len == inode->i_size);
+	err = ubifs_budget_space(c, &req);
+	if (err)
+		return err;
+
+	mutex_lock(&host_ui->ui_mutex);
+	host->i_ctime = ubifs_current_time(host);
+	host_ui->xattr_size -= CALC_XATTR_BYTES(ui->data_len);
+	host_ui->xattr_size += CALC_XATTR_BYTES(size);
+
+	kfree(ui->data);
+	ui->data = kmalloc(size, GFP_NOFS);
+	if (!ui->data) {
+		err = -ENOMEM;
+		goto out_unlock;
+	}
+
+	memcpy(ui->data, value, size);
+	inode->i_size = ui->ui_size = size;
+	ui->data_len = size;
+
+	/*
+	 * It is important to write the host inode after the xattr inode
+	 * because if the host inode gets synchronized (via 'fsync()'), then
+	 * the extended attribute inode gets synchronized, because it goes
+	 * before the host inode in the write-buffer.
+	 */
+	err = ubifs_jnl_change_xattr(c, inode, host);
+	if (err)
+		goto out_cancel;
+	mutex_unlock(&host_ui->ui_mutex);
+
+	ubifs_release_budget(c, &req);
+	return 0;
+
+out_cancel:
+	host_ui->xattr_size -= CALC_XATTR_BYTES(size);
+	host_ui->xattr_size += CALC_XATTR_BYTES(ui->data_len);
+	make_bad_inode(inode);
+out_unlock:
+	mutex_unlock(&host_ui->ui_mutex);
+	ubifs_release_budget(c, &req);
+	return err;
+}
+
+/**
+ * check_namespace - check extended attribute name-space.
+ * @nm: extended attribute name
+ *
+ * This function makes sure the extended attribute name belongs to one of the
+ * supported extended attribute name-spaces. Returns name-space index in case
+ * of success and a negative error code in case of failure.
+ */
+static int check_namespace(const struct qstr *nm)
+{
+	int type;
+
+	if (nm->len > UBIFS_MAX_NLEN)
+		return -ENAMETOOLONG;
+
+	if (!strncmp(nm->name, XATTR_TRUSTED_PREFIX,
+		     XATTR_TRUSTED_PREFIX_LEN)) {
+		if (nm->name[sizeof(XATTR_TRUSTED_PREFIX) - 1] == '\0')
+			return -EINVAL;
+		type = TRUSTED_XATTR;
+	} else if (!strncmp(nm->name, XATTR_USER_PREFIX,
+				      XATTR_USER_PREFIX_LEN)) {
+		if (nm->name[XATTR_USER_PREFIX_LEN] == '\0')
+			return -EINVAL;
+		type = USER_XATTR;
+	} else if (!strncmp(nm->name, XATTR_SECURITY_PREFIX,
+				     XATTR_SECURITY_PREFIX_LEN)) {
+		if (nm->name[sizeof(XATTR_SECURITY_PREFIX) - 1] == '\0')
+			return -EINVAL;
+		type = SECURITY_XATTR;
+	} else
+		return -EOPNOTSUPP;
+
+	return type;
+}
+
+static struct inode *iget_xattr(struct ubifs_info *c, ino_t inum)
+{
+	struct inode *inode;
+
+	inode = ubifs_iget(c->vfs_sb, inum);
+	if (IS_ERR(inode)) {
+		ubifs_err("dead extended attribute entry, error %d",
+			  (int)PTR_ERR(inode));
+		return inode;
+	}
+	if (ubifs_inode(inode)->xattr)
+		return inode;
+	ubifs_err("corrupt extended attribute entry");
+	iput(inode);
+	return ERR_PTR(-EINVAL);
+}
+
+int ubifs_setxattr(struct dentry *dentry, const char *name,
+		   const void *value, size_t size, int flags)
+{
+	struct inode *inode, *host = dentry->d_inode;
+	struct ubifs_info *c = host->i_sb->s_fs_info;
+	struct qstr nm = { .name = name, .len = strlen(name) };
+	struct ubifs_dent_node *xent;
+	union ubifs_key key;
+	int err, type;
+
+	dbg_gen("xattr '%s', host ino %lu ('%.*s'), size %zd", name,
+		host->i_ino, dentry->d_name.len, dentry->d_name.name, size);
+
+	if (size > UBIFS_MAX_INO_DATA)
+		return -ERANGE;
+
+	type = check_namespace(&nm);
+	if (type < 0)
+		return type;
+
+	xent = kmalloc(UBIFS_MAX_XENT_NODE_SZ, GFP_NOFS);
+	if (!xent)
+		return -ENOMEM;
+
+	/*
+	 * The extended attribute entries are stored in LNC, so multiple
+	 * look-ups do not involve reading the flash.
+	 */
+	xent_key_init(c, &key, host->i_ino, &nm);
+	err = ubifs_tnc_lookup_nm(c, &key, xent, &nm);
+	if (err) {
+		if (err != -ENOENT)
+			goto out_free;
+
+		if (flags & XATTR_REPLACE)
+			/* We are asked not to create the xattr */
+			err = -ENODATA;
+		else
+			err = create_xattr(c, host, &nm, value, size);
+		goto out_free;
+	}
+
+	if (flags & XATTR_CREATE) {
+		/* We are asked not to replace the xattr */
+		err = -EEXIST;
+		goto out_free;
+	}
+
+	inode = iget_xattr(c, le64_to_cpu(xent->inum));
+	if (IS_ERR(inode)) {
+		err = PTR_ERR(inode);
+		goto out_free;
+	}
+
+	err = change_xattr(c, host, inode, value, size);
+	iput(inode);
+
+out_free:
+	kfree(xent);
+	return err;
+}
+
+ssize_t ubifs_getxattr(struct dentry *dentry, const char *name, void *buf,
+		       size_t size)
+{
+	struct inode *inode, *host = dentry->d_inode;
+	struct ubifs_info *c = host->i_sb->s_fs_info;
+	struct qstr nm = { .name = name, .len = strlen(name) };
+	struct ubifs_inode *ui;
+	struct ubifs_dent_node *xent;
+	union ubifs_key key;
+	int err;
+
+	dbg_gen("xattr '%s', ino %lu ('%.*s'), buf size %zd", name,
+		host->i_ino, dentry->d_name.len, dentry->d_name.name, size);
+
+	err = check_namespace(&nm);
+	if (err < 0)
+		return err;
+
+	xent = kmalloc(UBIFS_MAX_XENT_NODE_SZ, GFP_NOFS);
+	if (!xent)
+		return -ENOMEM;
+
+	mutex_lock(&host->i_mutex);
+	xent_key_init(c, &key, host->i_ino, &nm);
+	err = ubifs_tnc_lookup_nm(c, &key, xent, &nm);
+	if (err) {
+		if (err == -ENOENT)
+			err = -ENODATA;
+		goto out_unlock;
+	}
+
+	inode = iget_xattr(c, le64_to_cpu(xent->inum));
+	if (IS_ERR(inode)) {
+		err = PTR_ERR(inode);
+		goto out_unlock;
+	}
+
+	ui = ubifs_inode(inode);
+	ubifs_assert(inode->i_size == ui->data_len);
+	ubifs_assert(ubifs_inode(host)->xattr_size > ui->data_len);
+
+	if (buf) {
+		/* If @buf is %NULL we are supposed to return the length */
+		if (ui->data_len > size) {
+			dbg_err("buffer size %zd, xattr len %d",
+				size, ui->data_len);
+			err = -ERANGE;
+			goto out_iput;
+		}
+
+		memcpy(buf, ui->data, ui->data_len);
+	}
+	err = ui->data_len;
+
+out_iput:
+	iput(inode);
+out_unlock:
+	mutex_unlock(&host->i_mutex);
+	kfree(xent);
+	return err;
+}
+
+ssize_t ubifs_listxattr(struct dentry *dentry, char *buffer, size_t size)
+{
+	union ubifs_key key;
+	struct inode *host = dentry->d_inode;
+	struct ubifs_info *c = host->i_sb->s_fs_info;
+	struct ubifs_inode *host_ui = ubifs_inode(host);
+	struct ubifs_dent_node *xent, *pxent = NULL;
+	int err, len, written = 0;
+	struct qstr nm = { .name = NULL };
+
+	dbg_gen("ino %lu ('%.*s'), buffer size %zd", host->i_ino,
+		dentry->d_name.len, dentry->d_name.name, size);
+
+	len = host_ui->xattr_names + host_ui->xattr_cnt;
+	if (!buffer)
+		/*
+		 * We should return the minimum buffer size which will fit a
+		 * null-terminated list of all the extended attribute names.
+		 */
+		return len;
+
+	if (len > size)
+		return -ERANGE;
+
+	lowest_xent_key(c, &key, host->i_ino);
+
+	mutex_lock(&host->i_mutex);
+	while (1) {
+		int type;
+
+		xent = ubifs_tnc_next_ent(c, &key, &nm);
+		if (unlikely(IS_ERR(xent))) {
+			err = PTR_ERR(xent);
+			break;
+		}
+
+		nm.name = xent->name;
+		nm.len = le16_to_cpu(xent->nlen);
+
+		type = check_namespace(&nm);
+		if (unlikely(type < 0)) {
+			err = type;
+			break;
+		}
+
+		/* Show trusted namespace only for "power" users */
+		if (type != TRUSTED_XATTR || capable(CAP_SYS_ADMIN)) {
+			memcpy(buffer + written, nm.name, nm.len + 1);
+			written += nm.len + 1;
+		}
+
+		kfree(pxent);
+		pxent = xent;
+		key_read(c, &xent->key, &key);
+	}
+	mutex_unlock(&host->i_mutex);
+
+	kfree(pxent);
+	if (err != -ENOENT) {
+		ubifs_err("cannot find next direntry, error %d", err);
+		return err;
+	}
+
+	ubifs_assert(written <= size);
+	return written;
+}
+
+static int remove_xattr(struct ubifs_info *c, struct inode *host,
+			struct inode *inode, const struct qstr *nm)
+{
+	int err;
+	struct ubifs_inode *host_ui = ubifs_inode(host);
+	struct ubifs_inode *ui = ubifs_inode(inode);
+	struct ubifs_budget_req req = { .dirtied_ino = 1, .mod_dent = 1,
+					.dirtied_ino_d = host_ui->data_len };
+
+	ubifs_assert(ui->data_len == inode->i_size);
+
+	err = ubifs_budget_space(c, &req);
+	if (err)
+		return err;
+
+	mutex_lock(&host_ui->ui_mutex);
+	host->i_ctime = ubifs_current_time(host);
+	host_ui->xattr_cnt -= 1;
+	host_ui->xattr_size -= CALC_DENT_SIZE(nm->len);
+	host_ui->xattr_size -= CALC_XATTR_BYTES(ui->data_len);
+	host_ui->xattr_names -= nm->len;
+
+	err = ubifs_jnl_delete_xattr(c, host, inode, nm);
+	if (err)
+		goto out_cancel;
+	mutex_unlock(&host_ui->ui_mutex);
+
+	ubifs_release_budget(c, &req);
+	return 0;
+
+out_cancel:
+	host_ui->xattr_cnt += 1;
+	host_ui->xattr_size += CALC_DENT_SIZE(nm->len);
+	host_ui->xattr_size += CALC_XATTR_BYTES(ui->data_len);
+	mutex_unlock(&host_ui->ui_mutex);
+	ubifs_release_budget(c, &req);
+	make_bad_inode(inode);
+	return err;
+}
+
+int ubifs_removexattr(struct dentry *dentry, const char *name)
+{
+	struct inode *inode, *host = dentry->d_inode;
+	struct ubifs_info *c = host->i_sb->s_fs_info;
+	struct qstr nm = { .name = name, .len = strlen(name) };
+	struct ubifs_dent_node *xent;
+	union ubifs_key key;
+	int err;
+
+	dbg_gen("xattr '%s', ino %lu ('%.*s')", name,
+		host->i_ino, dentry->d_name.len, dentry->d_name.name);
+	ubifs_assert(mutex_is_locked(&host->i_mutex));
+
+	err = check_namespace(&nm);
+	if (err < 0)
+		return err;
+
+	xent = kmalloc(UBIFS_MAX_XENT_NODE_SZ, GFP_NOFS);
+	if (!xent)
+		return -ENOMEM;
+
+	xent_key_init(c, &key, host->i_ino, &nm);
+	err = ubifs_tnc_lookup_nm(c, &key, xent, &nm);
+	if (err) {
+		if (err == -ENOENT)
+			err = -ENODATA;
+		goto out_free;
+	}
+
+	inode = iget_xattr(c, le64_to_cpu(xent->inum));
+	if (IS_ERR(inode)) {
+		err = PTR_ERR(inode);
+		goto out_free;
+	}
+
+	ubifs_assert(inode->i_nlink == 1);
+	inode->i_nlink = 0;
+	err = remove_xattr(c, host, inode, &nm);
+	if (err)
+		inode->i_nlink = 1;
+
+	/* If @i_nlink is 0, 'iput()' will delete the inode */
+	iput(inode);
+
+out_free:
+	kfree(xent);
+	return err;
+}
diff --git a/fs/vfat/namei.c b/fs/vfat/namei.c
index a3522727ea5..b546ba69be8 100644
--- a/fs/vfat/namei.c
+++ b/fs/vfat/namei.c
@@ -645,7 +645,7 @@ static int vfat_add_entry(struct inode *dir, struct qstr *qname, int is_dir,
 	if (len == 0)
 		return -ENOENT;
 
-	slots = kmalloc(sizeof(*slots) * MSDOS_SLOTS, GFP_KERNEL);
+	slots = kmalloc(sizeof(*slots) * MSDOS_SLOTS, GFP_NOFS);
 	if (slots == NULL)
 		return -ENOMEM;
 
@@ -687,7 +687,7 @@ static struct dentry *vfat_lookup(struct inode *dir, struct dentry *dentry,
 	struct dentry *alias;
 	int err, table;
 
-	lock_kernel();
+	lock_super(sb);
 	table = (MSDOS_SB(sb)->options.name_check == 's') ? 2 : 0;
 	dentry->d_op = &vfat_dentry_ops[table];
 
@@ -699,7 +699,7 @@ static struct dentry *vfat_lookup(struct inode *dir, struct dentry *dentry,
 	inode = fat_build_inode(sb, sinfo.de, sinfo.i_pos);
 	brelse(sinfo.bh);
 	if (IS_ERR(inode)) {
-		unlock_kernel();
+		unlock_super(sb);
 		return ERR_CAST(inode);
 	}
 	alias = d_find_alias(inode);
@@ -708,13 +708,13 @@ static struct dentry *vfat_lookup(struct inode *dir, struct dentry *dentry,
 			dput(alias);
 		else {
 			iput(inode);
-			unlock_kernel();
+			unlock_super(sb);
 			return alias;
 		}
 
 	}
 error:
-	unlock_kernel();
+	unlock_super(sb);
 	dentry->d_op = &vfat_dentry_ops[table];
 	dentry->d_time = dentry->d_parent->d_inode->i_version;
 	dentry = d_splice_alias(inode, dentry);
@@ -734,7 +734,7 @@ static int vfat_create(struct inode *dir, struct dentry *dentry, int mode,
 	struct timespec ts;
 	int err;
 
-	lock_kernel();
+	lock_super(sb);
 
 	ts = CURRENT_TIME_SEC;
 	err = vfat_add_entry(dir, &dentry->d_name, 0, 0, &ts, &sinfo);
@@ -755,17 +755,18 @@ static int vfat_create(struct inode *dir, struct dentry *dentry, int mode,
 	dentry->d_time = dentry->d_parent->d_inode->i_version;
 	d_instantiate(dentry, inode);
 out:
-	unlock_kernel();
+	unlock_super(sb);
 	return err;
 }
 
 static int vfat_rmdir(struct inode *dir, struct dentry *dentry)
 {
 	struct inode *inode = dentry->d_inode;
+	struct super_block *sb = dir->i_sb;
 	struct fat_slot_info sinfo;
 	int err;
 
-	lock_kernel();
+	lock_super(sb);
 
 	err = fat_dir_empty(inode);
 	if (err)
@@ -783,7 +784,7 @@ static int vfat_rmdir(struct inode *dir, struct dentry *dentry)
 	inode->i_mtime = inode->i_atime = CURRENT_TIME_SEC;
 	fat_detach(inode);
 out:
-	unlock_kernel();
+	unlock_super(sb);
 
 	return err;
 }
@@ -791,10 +792,11 @@ out:
 static int vfat_unlink(struct inode *dir, struct dentry *dentry)
 {
 	struct inode *inode = dentry->d_inode;
+	struct super_block *sb = dir->i_sb;
 	struct fat_slot_info sinfo;
 	int err;
 
-	lock_kernel();
+	lock_super(sb);
 
 	err = vfat_find(dir, &dentry->d_name, &sinfo);
 	if (err)
@@ -807,7 +809,7 @@ static int vfat_unlink(struct inode *dir, struct dentry *dentry)
 	inode->i_mtime = inode->i_atime = CURRENT_TIME_SEC;
 	fat_detach(inode);
 out:
-	unlock_kernel();
+	unlock_super(sb);
 
 	return err;
 }
@@ -820,7 +822,7 @@ static int vfat_mkdir(struct inode *dir, struct dentry *dentry, int mode)
 	struct timespec ts;
 	int err, cluster;
 
-	lock_kernel();
+	lock_super(sb);
 
 	ts = CURRENT_TIME_SEC;
 	cluster = fat_alloc_new_dir(dir, &ts);
@@ -849,13 +851,13 @@ static int vfat_mkdir(struct inode *dir, struct dentry *dentry, int mode)
 	dentry->d_time = dentry->d_parent->d_inode->i_version;
 	d_instantiate(dentry, inode);
 
-	unlock_kernel();
+	unlock_super(sb);
 	return 0;
 
 out_free:
 	fat_free_clusters(dir, cluster);
 out:
-	unlock_kernel();
+	unlock_super(sb);
 	return err;
 }
 
@@ -869,11 +871,12 @@ static int vfat_rename(struct inode *old_dir, struct dentry *old_dentry,
 	struct timespec ts;
 	loff_t dotdot_i_pos, new_i_pos;
 	int err, is_dir, update_dotdot, corrupt = 0;
+	struct super_block *sb = old_dir->i_sb;
 
 	old_sinfo.bh = sinfo.bh = dotdot_bh = NULL;
 	old_inode = old_dentry->d_inode;
 	new_inode = new_dentry->d_inode;
-	lock_kernel();
+	lock_super(sb);
 	err = vfat_find(old_dir, &old_dentry->d_name, &old_sinfo);
 	if (err)
 		goto out;
@@ -951,7 +954,7 @@ out:
 	brelse(sinfo.bh);
 	brelse(dotdot_bh);
 	brelse(old_sinfo.bh);
-	unlock_kernel();
+	unlock_super(sb);
 
 	return err;
 
diff --git a/fs/xfs/xfs_log.c b/fs/xfs/xfs_log.c
index afaee301b0e..ad3d26ddfe3 100644
--- a/fs/xfs/xfs_log.c
+++ b/fs/xfs/xfs_log.c
@@ -2427,13 +2427,20 @@ restart:
 	if (iclog->ic_size - iclog->ic_offset < 2*sizeof(xlog_op_header_t)) {
 		xlog_state_switch_iclogs(log, iclog, iclog->ic_size);
 
-		/* If I'm the only one writing to this iclog, sync it to disk */
-		if (atomic_read(&iclog->ic_refcnt) == 1) {
+		/*
+		 * If I'm the only one writing to this iclog, sync it to disk.
+		 * We need to do an atomic compare and decrement here to avoid
+		 * racing with concurrent atomic_dec_and_lock() calls in
+		 * xlog_state_release_iclog() when there is more than one
+		 * reference to the iclog.
+		 */
+		if (!atomic_add_unless(&iclog->ic_refcnt, -1, 1)) {
+			/* we are the only one */
 			spin_unlock(&log->l_icloglock);
-			if ((error = xlog_state_release_iclog(log, iclog)))
+			error = xlog_state_release_iclog(log, iclog);
+			if (error)
 				return error;
 		} else {
-			atomic_dec(&iclog->ic_refcnt);
 			spin_unlock(&log->l_icloglock);
 		}
 		goto restart;
author	David S. Miller <davem@davemloft.net>	2008-07-18 02:39:39 -0700
committer	David S. Miller <davem@davemloft.net>	2008-07-18 02:39:39 -0700
commit	49997d75152b3d23c53b0fa730599f2f74c92c65 (patch)
tree	46e93126170d02cfec9505172e545732c1b69656 /fs
parent	a0c80b80e0fb48129e4e9d6a9ede914f9ff1850d (diff)
parent	5b664cb235e97afbf34db9c4d77f08ebd725335e (diff)