Merge branch 'akpm' (Andrew's patch-bomb)

Merge Andrew's first set of patches:
 "Non-MM patches:

   - lots of misc bits

   - tree-wide have_clk() cleanups

   - quite a lot of printk tweaks.  I draw your attention to "printk:
     convert the format for KERN_<LEVEL> to a 2 byte pattern" which
     looks a bit scary.  But afaict it's solid.

   - backlight updates

   - lib/ feature work (notably the addition and use of memweight())

   - checkpatch updates

   - rtc updates

   - nilfs updates

   - fatfs updates (partial, still waiting for acks)

   - kdump, proc, fork, IPC, sysctl, taskstats, pps, etc

   - new fault-injection feature work"

* Merge emailed patches from Andrew Morton <akpm@linux-foundation.org>: (128 commits)
  drivers/misc/lkdtm.c: fix missing allocation failure check
  lib/scatterlist: do not re-write gfp_flags in __sg_alloc_table()
  fault-injection: add tool to run command with failslab or fail_page_alloc
  fault-injection: add selftests for cpu and memory hotplug
  powerpc: pSeries reconfig notifier error injection module
  memory: memory notifier error injection module
  PM: PM notifier error injection module
  cpu: rewrite cpu-notifier-error-inject module
  fault-injection: notifier error injection
  c/r: fcntl: add F_GETOWNER_UIDS option
  resource: make sure requested range is included in the root range
  include/linux/aio.h: cpp->C conversions
  fs: cachefiles: add support for large files in filesystem caching
  pps: return PTR_ERR on error in device_create
  taskstats: check nla_reserve() return
  sysctl: suppress kmemleak messages
  ipc: use Kconfig options for __ARCH_WANT_[COMPAT_]IPC_PARSE_VERSION
  ipc: compat: use signed size_t types for msgsnd and msgrcv
  ipc: allow compat IPC version field parsing if !ARCH_WANT_OLD_COMPAT_IPC
  ipc: add COMPAT_SHMLBA support
  ...

40 files changed, 408 insertions, 300 deletions

diff --git a/fs/affs/bitmap.c b/fs/affs/bitmap.c
index 6e0be43ef6e..a32246b8359 100644
--- a/fs/affs/bitmap.c
+++ b/fs/affs/bitmap.c
@@ -10,30 +10,6 @@
 #include <linux/slab.h>
 #include "affs.h"
 
-/* This is, of course, shamelessly stolen from fs/minix */
-
-static const int nibblemap[] = { 0,1,1,2,1,2,2,3,1,2,2,3,2,3,3,4 };
-
-static u32
-affs_count_free_bits(u32 blocksize, const void *data)
-{
-	const u32 *map;
-	u32 free;
-	u32 tmp;
-
-	map = data;
-	free = 0;
-	for (blocksize /= 4; blocksize > 0; blocksize--) {
-		tmp = *map++;
-		while (tmp) {
-			free += nibblemap[tmp & 0xf];
-			tmp >>= 4;
-		}
-	}
-
-	return free;
-}
-
 u32
 affs_count_free_blocks(struct super_block *sb)
 {
@@ -317,7 +293,7 @@ int affs_init_bitmap(struct super_block *sb, int *flags)
 			goto out;
 		}
 		pr_debug("AFFS: read bitmap block %d: %d\n", blk, bm->bm_key);
-		bm->bm_free = affs_count_free_bits(sb->s_blocksize - 4, bh->b_data + 4);
+		bm->bm_free = memweight(bh->b_data + 4, sb->s_blocksize - 4);
 
 		/* Don't try read the extension if this is the last block,
 		 * but we also need the right bm pointer below
@@ -367,7 +343,7 @@ int affs_init_bitmap(struct super_block *sb, int *flags)
 
 	/* recalculate bitmap count for last block */
 	bm--;
-	bm->bm_free = affs_count_free_bits(sb->s_blocksize - 4, bh->b_data + 4);
+	bm->bm_free = memweight(bh->b_data + 4, sb->s_blocksize - 4);
 
 out:
 	affs_brelse(bh);
diff --git a/fs/btrfs/ctree.h b/fs/btrfs/ctree.h
index adb1cd7ceb9..4bab807227a 100644
--- a/fs/btrfs/ctree.h
+++ b/fs/btrfs/ctree.h
@@ -3342,10 +3342,22 @@ ssize_t btrfs_listxattr(struct dentry *dentry, char *buffer, size_t size);
 /* super.c */
 int btrfs_parse_options(struct btrfs_root *root, char *options);
 int btrfs_sync_fs(struct super_block *sb, int wait);
+
+#ifdef CONFIG_PRINTK
+__printf(2, 3)
 void btrfs_printk(struct btrfs_fs_info *fs_info, const char *fmt, ...);
+#else
+static inline __printf(2, 3)
+void btrfs_printk(struct btrfs_fs_info *fs_info, const char *fmt, ...)
+{
+}
+#endif
+
+__printf(5, 6)
 void __btrfs_std_error(struct btrfs_fs_info *fs_info, const char *function,
 		     unsigned int line, int errno, const char *fmt, ...);
 
+
 void __btrfs_abort_transaction(struct btrfs_trans_handle *trans,
 			       struct btrfs_root *root, const char *function,
 			       unsigned int line, int errno);
@@ -3386,6 +3398,7 @@ do {								\
 			  (errno), fmt, ##args);		\
 } while (0)
 
+__printf(5, 6)
 void __btrfs_panic(struct btrfs_fs_info *fs_info, const char *function,
 		   unsigned int line, int errno, const char *fmt, ...);
 
diff --git a/fs/btrfs/disk-io.c b/fs/btrfs/disk-io.c
index 502b20c56e8..fadeba6a5db 100644
--- a/fs/btrfs/disk-io.c
+++ b/fs/btrfs/disk-io.c
@@ -1114,7 +1114,7 @@ void clean_tree_block(struct btrfs_trans_handle *trans, struct btrfs_root *root,
 				spin_unlock(&root->fs_info->delalloc_lock);
 				btrfs_panic(root->fs_info, -EOVERFLOW,
 					  "Can't clear %lu bytes from "
-					  " dirty_mdatadata_bytes (%lu)",
+					  " dirty_mdatadata_bytes (%llu)",
 					  buf->len,
 					  root->fs_info->dirty_metadata_bytes);
 			}
diff --git a/fs/btrfs/relocation.c b/fs/btrfs/relocation.c
index c5dbd914967..4da08652004 100644
--- a/fs/btrfs/relocation.c
+++ b/fs/btrfs/relocation.c
@@ -1241,7 +1241,7 @@ static int __must_check __add_reloc_root(struct btrfs_root *root)
 	if (rb_node) {
 		btrfs_panic(root->fs_info, -EEXIST, "Duplicate root found "
 			    "for start=%llu while inserting into relocation "
-			    "tree\n");
+			    "tree\n", node->bytenr);
 		kfree(node);
 		return -EEXIST;
 	}
diff --git a/fs/btrfs/super.c b/fs/btrfs/super.c
index fa61ef59cd6..8c6e61d6eed 100644
--- a/fs/btrfs/super.c
+++ b/fs/btrfs/super.c
@@ -125,6 +125,7 @@ static void btrfs_handle_error(struct btrfs_fs_info *fs_info)
 	}
 }
 
+#ifdef CONFIG_PRINTK
 /*
  * __btrfs_std_error decodes expected errors from the caller and
  * invokes the approciate error response.
@@ -167,7 +168,7 @@ void __btrfs_std_error(struct btrfs_fs_info *fs_info, const char *function,
 	va_end(args);
 }
 
-const char *logtypes[] = {
+static const char * const logtypes[] = {
 	"emergency",
 	"alert",
 	"critical",
@@ -185,22 +186,50 @@ void btrfs_printk(struct btrfs_fs_info *fs_info, const char *fmt, ...)
 	struct va_format vaf;
 	va_list args;
 	const char *type = logtypes[4];
+	int kern_level;
 
 	va_start(args, fmt);
 
-	if (fmt[0] == '<' && isdigit(fmt[1]) && fmt[2] == '>') {
-		memcpy(lvl, fmt, 3);
-		lvl[3] = '\0';
-		fmt += 3;
-		type = logtypes[fmt[1] - '0'];
+	kern_level = printk_get_level(fmt);
+	if (kern_level) {
+		size_t size = printk_skip_level(fmt) - fmt;
+		memcpy(lvl, fmt,  size);
+		lvl[size] = '\0';
+		fmt += size;
+		type = logtypes[kern_level - '0'];
 	} else
 		*lvl = '\0';
 
 	vaf.fmt = fmt;
 	vaf.va = &args;
+
 	printk("%sBTRFS %s (device %s): %pV", lvl, type, sb->s_id, &vaf);
+
+	va_end(args);
 }
 
+#else
+
+void __btrfs_std_error(struct btrfs_fs_info *fs_info, const char *function,
+		       unsigned int line, int errno, const char *fmt, ...)
+{
+	struct super_block *sb = fs_info->sb;
+
+	/*
+	 * Special case: if the error is EROFS, and we're already
+	 * under MS_RDONLY, then it is safe here.
+	 */
+	if (errno == -EROFS && (sb->s_flags & MS_RDONLY))
+		return;
+
+	/* Don't go through full error handling during mount */
+	if (sb->s_flags & MS_BORN) {
+		save_error_info(fs_info);
+		btrfs_handle_error(fs_info);
+	}
+}
+#endif
+
 /*
  * We only mark the transaction aborted and then set the file system read-only.
  * This will prevent new transactions from starting or trying to join this
diff --git a/fs/cachefiles/rdwr.c b/fs/cachefiles/rdwr.c
index c0353dfac51..c994691d944 100644
--- a/fs/cachefiles/rdwr.c
+++ b/fs/cachefiles/rdwr.c
@@ -919,7 +919,7 @@ int cachefiles_write_page(struct fscache_storage *op, struct page *page)
 	 * own time */
 	path.mnt = cache->mnt;
 	path.dentry = object->backer;
-	file = dentry_open(&path, O_RDWR, cache->cache_cred);
+	file = dentry_open(&path, O_RDWR | O_LARGEFILE, cache->cache_cred);
 	if (IS_ERR(file)) {
 		ret = PTR_ERR(file);
 	} else {
diff --git a/fs/exec.c b/fs/exec.c
index e95aeeddd25..3684353ebd5 100644
--- a/fs/exec.c
+++ b/fs/exec.c
@@ -2002,17 +2002,17 @@ static void coredump_finish(struct mm_struct *mm)
 void set_dumpable(struct mm_struct *mm, int value)
 {
 	switch (value) {
-	case 0:
+	case SUID_DUMPABLE_DISABLED:
 		clear_bit(MMF_DUMPABLE, &mm->flags);
 		smp_wmb();
 		clear_bit(MMF_DUMP_SECURELY, &mm->flags);
 		break;
-	case 1:
+	case SUID_DUMPABLE_ENABLED:
 		set_bit(MMF_DUMPABLE, &mm->flags);
 		smp_wmb();
 		clear_bit(MMF_DUMP_SECURELY, &mm->flags);
 		break;
-	case 2:
+	case SUID_DUMPABLE_SAFE:
 		set_bit(MMF_DUMP_SECURELY, &mm->flags);
 		smp_wmb();
 		set_bit(MMF_DUMPABLE, &mm->flags);
@@ -2025,7 +2025,7 @@ static int __get_dumpable(unsigned long mm_flags)
 	int ret;
 
 	ret = mm_flags & MMF_DUMPABLE_MASK;
-	return (ret >= 2) ? 2 : ret;
+	return (ret > SUID_DUMPABLE_ENABLED) ? SUID_DUMPABLE_SAFE : ret;
 }
 
 int get_dumpable(struct mm_struct *mm)
@@ -2111,6 +2111,7 @@ void do_coredump(long signr, int exit_code, struct pt_regs *regs)
 	int retval = 0;
 	int flag = 0;
 	int ispipe;
+	bool need_nonrelative = false;
 	static atomic_t core_dump_count = ATOMIC_INIT(0);
 	struct coredump_params cprm = {
 		.signr = signr,
@@ -2136,14 +2137,16 @@ void do_coredump(long signr, int exit_code, struct pt_regs *regs)
 	if (!cred)
 		goto fail;
 	/*
-	 *	We cannot trust fsuid as being the "true" uid of the
-	 *	process nor do we know its entire history. We only know it
-	 *	was tainted so we dump it as root in mode 2.
+	 * We cannot trust fsuid as being the "true" uid of the process
+	 * nor do we know its entire history. We only know it was tainted
+	 * so we dump it as root in mode 2, and only into a controlled
+	 * environment (pipe handler or fully qualified path).
 	 */
-	if (__get_dumpable(cprm.mm_flags) == 2) {
+	if (__get_dumpable(cprm.mm_flags) == SUID_DUMPABLE_SAFE) {
 		/* Setuid core dump mode */
 		flag = O_EXCL;		/* Stop rewrite attacks */
 		cred->fsuid = GLOBAL_ROOT_UID;	/* Dump root private */
+		need_nonrelative = true;
 	}
 
 	retval = coredump_wait(exit_code, &core_state);
@@ -2171,15 +2174,16 @@ void do_coredump(long signr, int exit_code, struct pt_regs *regs)
 		}
 
 		if (cprm.limit == 1) {
-			/*
+			/* See umh_pipe_setup() which sets RLIMIT_CORE = 1.
+			 *
 			 * Normally core limits are irrelevant to pipes, since
 			 * we're not writing to the file system, but we use
-			 * cprm.limit of 1 here as a speacial value. Any
-			 * non-1 limit gets set to RLIM_INFINITY below, but
-			 * a limit of 0 skips the dump.  This is a consistent
-			 * way to catch recursive crashes.  We can still crash
-			 * if the core_pattern binary sets RLIM_CORE =  !1
-			 * but it runs as root, and can do lots of stupid things
+			 * cprm.limit of 1 here as a speacial value, this is a
+			 * consistent way to catch recursive crashes.
+			 * We can still crash if the core_pattern binary sets
+			 * RLIM_CORE = !1, but it runs as root, and can do
+			 * lots of stupid things.
+			 *
 			 * Note that we use task_tgid_vnr here to grab the pid
 			 * of the process group leader.  That way we get the
 			 * right pid if a thread in a multi-threaded
@@ -2223,6 +2227,14 @@ void do_coredump(long signr, int exit_code, struct pt_regs *regs)
 		if (cprm.limit < binfmt->min_coredump)
 			goto fail_unlock;
 
+		if (need_nonrelative && cn.corename[0] != '/') {
+			printk(KERN_WARNING "Pid %d(%s) can only dump core "\
+				"to fully qualified path!\n",
+				task_tgid_vnr(current), current->comm);
+			printk(KERN_WARNING "Skipping core dump\n");
+			goto fail_unlock;
+		}
+
 		cprm.file = filp_open(cn.corename,
 				 O_CREAT | 2 | O_NOFOLLOW | O_LARGEFILE | flag,
 				 0600);
diff --git a/fs/ext2/balloc.c b/fs/ext2/balloc.c
index 1c361399886..376aa77f3ca 100644
--- a/fs/ext2/balloc.c
+++ b/fs/ext2/balloc.c
@@ -1444,19 +1444,9 @@ ext2_fsblk_t ext2_new_block(struct inode *inode, unsigned long goal, int *errp)
 
 #ifdef EXT2FS_DEBUG
 
-static const int nibblemap[] = {4, 3, 3, 2, 3, 2, 2, 1, 3, 2, 2, 1, 2, 1, 1, 0};
-
-unsigned long ext2_count_free (struct buffer_head * map, unsigned int numchars)
+unsigned long ext2_count_free(struct buffer_head *map, unsigned int numchars)
 {
-	unsigned int i;
-	unsigned long sum = 0;
-
-	if (!map)
-		return (0);
-	for (i = 0; i < numchars; i++)
-		sum += nibblemap[map->b_data[i] & 0xf] +
-			nibblemap[(map->b_data[i] >> 4) & 0xf];
-	return (sum);
+	return numchars * BITS_PER_BYTE - memweight(map->b_data, numchars);
 }
 
 #endif  /*  EXT2FS_DEBUG  */
diff --git a/fs/ext2/ialloc.c b/fs/ext2/ialloc.c
index c13eb7b91a1..8f370e012e6 100644
--- a/fs/ext2/ialloc.c
+++ b/fs/ext2/ialloc.c
@@ -644,6 +644,7 @@ unsigned long ext2_count_free_inodes (struct super_block * sb)
 	}
 	brelse(bitmap_bh);
 	printk("ext2_count_free_inodes: stored = %lu, computed = %lu, %lu\n",
+		(unsigned long)
 		percpu_counter_read(&EXT2_SB(sb)->s_freeinodes_counter),
 		desc_count, bitmap_count);
 	return desc_count;
diff --git a/fs/ext3/balloc.c b/fs/ext3/balloc.c
index 25cd6089211..90d901f0486 100644
--- a/fs/ext3/balloc.c
+++ b/fs/ext3/balloc.c
@@ -1813,7 +1813,7 @@ ext3_fsblk_t ext3_count_free_blocks(struct super_block *sb)
 	brelse(bitmap_bh);
 	printk("ext3_count_free_blocks: stored = "E3FSBLK
 		", computed = "E3FSBLK", "E3FSBLK"\n",
-	       le32_to_cpu(es->s_free_blocks_count),
+	       (ext3_fsblk_t)le32_to_cpu(es->s_free_blocks_count),
 		desc_count, bitmap_count);
 	return bitmap_count;
 #else
diff --git a/fs/ext3/bitmap.c b/fs/ext3/bitmap.c
index 909d13e2656..ef9c643e8e9 100644
--- a/fs/ext3/bitmap.c
+++ b/fs/ext3/bitmap.c
@@ -11,19 +11,9 @@
 
 #ifdef EXT3FS_DEBUG
 
-static const int nibblemap[] = {4, 3, 3, 2, 3, 2, 2, 1, 3, 2, 2, 1, 2, 1, 1, 0};
-
 unsigned long ext3_count_free (struct buffer_head * map, unsigned int numchars)
 {
-	unsigned int i;
-	unsigned long sum = 0;
-
-	if (!map)
-		return (0);
-	for (i = 0; i < numchars; i++)
-		sum += nibblemap[map->b_data[i] & 0xf] +
-			nibblemap[(map->b_data[i] >> 4) & 0xf];
-	return (sum);
+	return numchars * BITS_PER_BYTE - memweight(map->b_data, numchars);
 }
 
 #endif  /*  EXT3FS_DEBUG  */
diff --git a/fs/ext4/bitmap.c b/fs/ext4/bitmap.c
index a94b9c63ee5..f8716eab999 100644
--- a/fs/ext4/bitmap.c
+++ b/fs/ext4/bitmap.c
@@ -11,16 +11,9 @@
 #include <linux/jbd2.h>
 #include "ext4.h"
 
-static const int nibblemap[] = {4, 3, 3, 2, 3, 2, 2, 1, 3, 2, 2, 1, 2, 1, 1, 0};
-
 unsigned int ext4_count_free(char *bitmap, unsigned int numchars)
 {
-	unsigned int i, sum = 0;
-
-	for (i = 0; i < numchars; i++)
-		sum += nibblemap[bitmap[i] & 0xf] +
-			nibblemap[(bitmap[i] >> 4) & 0xf];
-	return sum;
+	return numchars * BITS_PER_BYTE - memweight(bitmap, numchars);
 }
 
 int ext4_inode_bitmap_csum_verify(struct super_block *sb, ext4_group_t group,
diff --git a/fs/fat/dir.c b/fs/fat/dir.c
index 6eaa28c98ad..dc49ed2cbff 100644
--- a/fs/fat/dir.c
+++ b/fs/fat/dir.c
@@ -35,6 +35,11 @@
 #define FAT_MAX_UNI_CHARS	((MSDOS_SLOTS - 1) * 13 + 1)
 #define FAT_MAX_UNI_SIZE	(FAT_MAX_UNI_CHARS * sizeof(wchar_t))
 
+static inline unsigned char fat_tolower(unsigned char c)
+{
+	return ((c >= 'A') && (c <= 'Z')) ? c+32 : c;
+}
+
 static inline loff_t fat_make_i_pos(struct super_block *sb,
 				    struct buffer_head *bh,
 				    struct msdos_dir_entry *de)
@@ -333,6 +338,124 @@ parse_long:
 	return 0;
 }
 
+/**
+ * fat_parse_short - Parse MS-DOS (short) directory entry.
+ * @sb:		superblock
+ * @de:		directory entry to parse
+ * @name:	FAT_MAX_SHORT_SIZE array in which to place extracted name
+ * @dot_hidden:	Nonzero == prepend '.' to names with ATTR_HIDDEN
+ *
+ * Returns the number of characters extracted into 'name'.
+ */
+static int fat_parse_short(struct super_block *sb,
+			   const struct msdos_dir_entry *de,
+			   unsigned char *name, int dot_hidden)
+{
+	const struct msdos_sb_info *sbi = MSDOS_SB(sb);
+	int isvfat = sbi->options.isvfat;
+	int nocase = sbi->options.nocase;
+	unsigned short opt_shortname = sbi->options.shortname;
+	struct nls_table *nls_disk = sbi->nls_disk;
+	wchar_t uni_name[14];
+	unsigned char c, work[MSDOS_NAME];
+	unsigned char *ptname = name;
+	int chi, chl, i, j, k;
+	int dotoffset = 0;
+	int name_len = 0, uni_len = 0;
+
+	if (!isvfat && dot_hidden && (de->attr & ATTR_HIDDEN)) {
+		*ptname++ = '.';
+		dotoffset = 1;
+	}
+
+	memcpy(work, de->name, sizeof(work));
+	/* see namei.c, msdos_format_name */
+	if (work[0] == 0x05)
+		work[0] = 0xE5;
+
+	/* Filename */
+	for (i = 0, j = 0; i < 8;) {
+		c = work[i];
+		if (!c)
+			break;
+		chl = fat_shortname2uni(nls_disk, &work[i], 8 - i,
+					&uni_name[j++], opt_shortname,
+					de->lcase & CASE_LOWER_BASE);
+		if (chl <= 1) {
+			if (!isvfat)
+				ptname[i] = nocase ? c : fat_tolower(c);
+			i++;
+			if (c != ' ') {
+				name_len = i;
+				uni_len  = j;
+			}
+		} else {
+			uni_len = j;
+			if (isvfat)
+				i += min(chl, 8-i);
+			else {
+				for (chi = 0; chi < chl && i < 8; chi++, i++)
+					ptname[i] = work[i];
+			}
+			if (chl)
+				name_len = i;
+		}
+	}
+
+	i = name_len;
+	j = uni_len;
+	fat_short2uni(nls_disk, ".", 1, &uni_name[j++]);
+	if (!isvfat)
+		ptname[i] = '.';
+	i++;
+
+	/* Extension */
+	for (k = 8; k < MSDOS_NAME;) {
+		c = work[k];
+		if (!c)
+			break;
+		chl = fat_shortname2uni(nls_disk, &work[k], MSDOS_NAME - k,
+					&uni_name[j++], opt_shortname,
+					de->lcase & CASE_LOWER_EXT);
+		if (chl <= 1) {
+			k++;
+			if (!isvfat)
+				ptname[i] = nocase ? c : fat_tolower(c);
+			i++;
+			if (c != ' ') {
+				name_len = i;
+				uni_len  = j;
+			}
+		} else {
+			uni_len = j;
+			if (isvfat) {
+				int offset = min(chl, MSDOS_NAME-k);
+				k += offset;
+				i += offset;
+			} else {
+				for (chi = 0; chi < chl && k < MSDOS_NAME;
+				     chi++, i++, k++) {
+						ptname[i] = work[k];
+				}
+			}
+			if (chl)
+				name_len = i;
+		}
+	}
+
+	if (name_len > 0) {
+		name_len += dotoffset;
+
+		if (sbi->options.isvfat) {
+			uni_name[uni_len] = 0x0000;
+			name_len = fat_uni_to_x8(sb, uni_name, name,
+						 FAT_MAX_SHORT_SIZE);
+		}
+	}
+
+	return name_len;
+}
+
 /*
  * Return values: negative -> error, 0 -> not found, positive -> found,
  * value is the total amount of slots, including the shortname entry.
@@ -344,15 +467,11 @@ int fat_search_long(struct inode *inode, const unsigned char *name,
 	struct msdos_sb_info *sbi = MSDOS_SB(sb);
 	struct buffer_head *bh = NULL;
 	struct msdos_dir_entry *de;
-	struct nls_table *nls_disk = sbi->nls_disk;
 	unsigned char nr_slots;
-	wchar_t bufuname[14];
 	wchar_t *unicode = NULL;
-	unsigned char work[MSDOS_NAME];
 	unsigned char bufname[FAT_MAX_SHORT_SIZE];
-	unsigned short opt_shortname = sbi->options.shortname;
 	loff_t cpos = 0;
-	int chl, i, j, last_u, err, len;
+	int err, len;
 
 	err = -ENOENT;
 	while (1) {
@@ -380,47 +499,16 @@ parse_record:
 				goto end_of_dir;
 		}
 
-		memcpy(work, de->name, sizeof(de->name));
-		/* see namei.c, msdos_format_name */
-		if (work[0] == 0x05)
-			work[0] = 0xE5;
-		for (i = 0, j = 0, last_u = 0; i < 8;) {
-			if (!work[i])
-				break;
-			chl = fat_shortname2uni(nls_disk, &work[i], 8 - i,
-						&bufuname[j++], opt_shortname,
-						de->lcase & CASE_LOWER_BASE);
-			if (chl <= 1) {
-				if (work[i] != ' ')
-					last_u = j;
-			} else {
-				last_u = j;
-			}
-			i += chl;
-		}
-		j = last_u;
-		fat_short2uni(nls_disk, ".", 1, &bufuname[j++]);
-		for (i = 8; i < MSDOS_NAME;) {
-			if (!work[i])
-				break;
-			chl = fat_shortname2uni(nls_disk, &work[i],
-						MSDOS_NAME - i,
-						&bufuname[j++], opt_shortname,
-						de->lcase & CASE_LOWER_EXT);
-			if (chl <= 1) {
-				if (work[i] != ' ')
-					last_u = j;
-			} else {
-				last_u = j;
-			}
-			i += chl;
-		}
-		if (!last_u)
+		/* Never prepend '.' to hidden files here.
+		 * That is done only for msdos mounts (and only when
+		 * 'dotsOK=yes'); if we are executing here, it is in the
+		 * context of a vfat mount.
+		 */
+		len = fat_parse_short(sb, de, bufname, 0);
+		if (len == 0)
 			continue;
 
 		/* Compare shortname */
-		bufuname[last_u] = 0x0000;
-		len = fat_uni_to_x8(sb, bufuname, bufname, sizeof(bufname));
 		if (fat_name_match(sbi, name, name_len, bufname, len))
 			goto found;
 
@@ -469,20 +557,15 @@ static int __fat_readdir(struct inode *inode, struct file *filp, void *dirent,
 	struct msdos_sb_info *sbi = MSDOS_SB(sb);
 	struct buffer_head *bh;
 	struct msdos_dir_entry *de;
-	struct nls_table *nls_disk = sbi->nls_disk;
 	unsigned char nr_slots;
-	wchar_t bufuname[14];
 	wchar_t *unicode = NULL;
-	unsigned char c, work[MSDOS_NAME];
-	unsigned char bufname[FAT_MAX_SHORT_SIZE], *ptname = bufname;
-	unsigned short opt_shortname = sbi->options.shortname;
+	unsigned char bufname[FAT_MAX_SHORT_SIZE];
 	int isvfat = sbi->options.isvfat;
-	int nocase = sbi->options.nocase;
 	const char *fill_name = NULL;
 	unsigned long inum;
 	unsigned long lpos, dummy, *furrfu = &lpos;
 	loff_t cpos;
-	int chi, chl, i, i2, j, last, last_u, dotoffset = 0, fill_len = 0;
+	int short_len = 0, fill_len = 0;
 	int ret = 0;
 
 	lock_super(sb);
@@ -556,74 +639,10 @@ parse_record:
 		}
 	}
 
-	if (sbi->options.dotsOK) {
-		ptname = bufname;
-		dotoffset = 0;
-		if (de->attr & ATTR_HIDDEN) {
-			*ptname++ = '.';
-			dotoffset = 1;
-		}
-	}
-
-	memcpy(work, de->name, sizeof(de->name));
-	/* see namei.c, msdos_format_name */
-	if (work[0] == 0x05)
-		work[0] = 0xE5;
-	for (i = 0, j = 0, last = 0, last_u = 0; i < 8;) {
-		if (!(c = work[i]))
-			break;
-		chl = fat_shortname2uni(nls_disk, &work[i], 8 - i,
-					&bufuname[j++], opt_shortname,
-					de->lcase & CASE_LOWER_BASE);
-		if (chl <= 1) {
-			ptname[i++] = (!nocase && c>='A' && c<='Z') ? c+32 : c;
-			if (c != ' ') {
-				last = i;
-				last_u = j;
-			}
-		} else {
-			last_u = j;
-			for (chi = 0; chi < chl && i < 8; chi++) {
-				ptname[i] = work[i];
-				i++; last = i;
-			}
-		}
-	}
-	i = last;
-	j = last_u;
-	fat_short2uni(nls_disk, ".", 1, &bufuname[j++]);
-	ptname[i++] = '.';
-	for (i2 = 8; i2 < MSDOS_NAME;) {
-		if (!(c = work[i2]))
-			break;
-		chl = fat_shortname2uni(nls_disk, &work[i2], MSDOS_NAME - i2,
-					&bufuname[j++], opt_shortname,
-					de->lcase & CASE_LOWER_EXT);
-		if (chl <= 1) {
-			i2++;
-			ptname[i++] = (!nocase && c>='A' && c<='Z') ? c+32 : c;
-			if (c != ' ') {
-				last = i;
-				last_u = j;
-			}
-		} else {
-			last_u = j;
-			for (chi = 0; chi < chl && i2 < MSDOS_NAME; chi++) {
-				ptname[i++] = work[i2++];
-				last = i;
-			}
-		}
-	}
-	if (!last)
+	short_len = fat_parse_short(sb, de, bufname, sbi->options.dotsOK);
+	if (short_len == 0)
 		goto record_end;
 
-	i = last + dotoffset;
-	j = last_u;
-
-	if (isvfat) {
-		bufuname[j] = 0x0000;
-		i = fat_uni_to_x8(sb, bufuname, bufname, sizeof(bufname));
-	}
 	if (nr_slots) {
 		/* hack for fat_ioctl_filldir() */
 		struct fat_ioctl_filldir_callback *p = dirent;
@@ -631,12 +650,12 @@ parse_record:
 		p->longname = fill_name;
 		p->long_len = fill_len;
 		p->shortname = bufname;
-		p->short_len = i;
+		p->short_len = short_len;
 		fill_name = NULL;
 		fill_len = 0;
 	} else {
 		fill_name = bufname;
-		fill_len = i;
+		fill_len = short_len;
 	}
 
 start_filldir:
diff --git a/fs/fat/fat.h b/fs/fat/fat.h
index fc35c5c6913..2deeeb86f33 100644
--- a/fs/fat/fat.h
+++ b/fs/fat/fat.h
@@ -217,6 +217,21 @@ static inline void fat16_towchar(wchar_t *dst, const __u8 *src, size_t len)
 #endif
 }
 
+static inline int fat_get_start(const struct msdos_sb_info *sbi,
+				const struct msdos_dir_entry *de)
+{
+	int cluster = le16_to_cpu(de->start);
+	if (sbi->fat_bits == 32)
+		cluster |= (le16_to_cpu(de->starthi) << 16);
+	return cluster;
+}
+
+static inline void fat_set_start(struct msdos_dir_entry *de, int cluster)
+{
+	de->start   = cpu_to_le16(cluster);
+	de->starthi = cpu_to_le16(cluster >> 16);
+}
+
 static inline void fatwchar_to16(__u8 *dst, const wchar_t *src, size_t len)
 {
 #ifdef __BIG_ENDIAN
diff --git a/fs/fat/inode.c b/fs/fat/inode.c
index 0038b32cb36..05e897fe986 100644
--- a/fs/fat/inode.c
+++ b/fs/fat/inode.c
@@ -369,10 +369,7 @@ static int fat_fill_inode(struct inode *inode, struct msdos_dir_entry *de)
 		inode->i_op = sbi->dir_ops;
 		inode->i_fop = &fat_dir_operations;
 
-		MSDOS_I(inode)->i_start = le16_to_cpu(de->start);
-		if (sbi->fat_bits == 32)
-			MSDOS_I(inode)->i_start |= (le16_to_cpu(de->starthi) << 16);
-
+		MSDOS_I(inode)->i_start = fat_get_start(sbi, de);
 		MSDOS_I(inode)->i_logstart = MSDOS_I(inode)->i_start;
 		error = fat_calc_dir_size(inode);
 		if (error < 0)
@@ -385,9 +382,7 @@ static int fat_fill_inode(struct inode *inode, struct msdos_dir_entry *de)
 		inode->i_mode = fat_make_mode(sbi, de->attr,
 			((sbi->options.showexec && !is_exec(de->name + 8))
 			 ? S_IRUGO|S_IWUGO : S_IRWXUGO));
-		MSDOS_I(inode)->i_start = le16_to_cpu(de->start);
-		if (sbi->fat_bits == 32)
-			MSDOS_I(inode)->i_start |= (le16_to_cpu(de->starthi) << 16);
+		MSDOS_I(inode)->i_start = fat_get_start(sbi, de);
 
 		MSDOS_I(inode)->i_logstart = MSDOS_I(inode)->i_start;
 		inode->i_size = le32_to_cpu(de->size);
@@ -613,8 +608,7 @@ retry:
 	else
 		raw_entry->size = cpu_to_le32(inode->i_size);
 	raw_entry->attr = fat_make_attrs(inode);
-	raw_entry->start = cpu_to_le16(MSDOS_I(inode)->i_logstart);
-	raw_entry->starthi = cpu_to_le16(MSDOS_I(inode)->i_logstart >> 16);
+	fat_set_start(raw_entry, MSDOS_I(inode)->i_logstart);
 	fat_time_unix2fat(sbi, &inode->i_mtime, &raw_entry->time,
 			  &raw_entry->date, NULL);
 	if (sbi->options.isvfat) {
diff --git a/fs/fat/namei_msdos.c b/fs/fat/namei_msdos.c
index 70d993a9380..b0e12bf9f4a 100644
--- a/fs/fat/namei_msdos.c
+++ b/fs/fat/namei_msdos.c
@@ -246,8 +246,7 @@ static int msdos_add_entry(struct inode *dir, const unsigned char *name,
 	de.ctime_cs = 0;
 	de.time = time;
 	de.date = date;
-	de.start = cpu_to_le16(cluster);
-	de.starthi = cpu_to_le16(cluster >> 16);
+	fat_set_start(&de, cluster);
 	de.size = 0;
 
 	err = fat_add_entries(dir, &de, 1, sinfo);
@@ -530,9 +529,7 @@ static int do_msdos_rename(struct inode *old_dir, unsigned char *old_name,
 		mark_inode_dirty(old_inode);
 
 	if (update_dotdot) {
-		int start = MSDOS_I(new_dir)->i_logstart;
-		dotdot_de->start = cpu_to_le16(start);
-		dotdot_de->starthi = cpu_to_le16(start >> 16);
+		fat_set_start(dotdot_de, MSDOS_I(new_dir)->i_logstart);
 		mark_buffer_dirty_inode(dotdot_bh, old_inode);
 		if (IS_DIRSYNC(new_dir)) {
 			err = sync_dirty_buffer(dotdot_bh);
@@ -572,9 +569,7 @@ error_dotdot:
 	corrupt = 1;
 
 	if (update_dotdot) {
-		int start = MSDOS_I(old_dir)->i_logstart;
-		dotdot_de->start = cpu_to_le16(start);
-		dotdot_de->starthi = cpu_to_le16(start >> 16);
+		fat_set_start(dotdot_de, MSDOS_I(old_dir)->i_logstart);
 		mark_buffer_dirty_inode(dotdot_bh, old_inode);
 		corrupt |= sync_dirty_buffer(dotdot_bh);
 	}
diff --git a/fs/fat/namei_vfat.c b/fs/fat/namei_vfat.c
index 6cc48065243..6a6d8c0715a 100644
--- a/fs/fat/namei_vfat.c
+++ b/fs/fat/namei_vfat.c
@@ -651,8 +651,7 @@ shortname:
 	de->time = de->ctime = time;
 	de->date = de->cdate = de->adate = date;
 	de->ctime_cs = time_cs;
-	de->start = cpu_to_le16(cluster);
-	de->starthi = cpu_to_le16(cluster >> 16);
+	fat_set_start(de, cluster);
 	de->size = 0;
 out_free:
 	__putname(uname);
@@ -965,9 +964,7 @@ static int vfat_rename(struct inode *old_dir, struct dentry *old_dentry,
 		mark_inode_dirty(old_inode);
 
 	if (update_dotdot) {
-		int start = MSDOS_I(new_dir)->i_logstart;
-		dotdot_de->start = cpu_to_le16(start);
-		dotdot_de->starthi = cpu_to_le16(start >> 16);
+		fat_set_start(dotdot_de, MSDOS_I(new_dir)->i_logstart);
 		mark_buffer_dirty_inode(dotdot_bh, old_inode);
 		if (IS_DIRSYNC(new_dir)) {
 			err = sync_dirty_buffer(dotdot_bh);
@@ -1009,9 +1006,7 @@ error_dotdot:
 	corrupt = 1;
 
 	if (update_dotdot) {
-		int start = MSDOS_I(old_dir)->i_logstart;
-		dotdot_de->start = cpu_to_le16(start);
-		dotdot_de->starthi = cpu_to_le16(start >> 16);
+		fat_set_start(dotdot_de, MSDOS_I(old_dir)->i_logstart);
 		mark_buffer_dirty_inode(dotdot_bh, old_inode);
 		corrupt |= sync_dirty_buffer(dotdot_bh);
 	}
diff --git a/fs/fcntl.c b/fs/fcntl.c
index 81b70e665bf..887b5ba8c9b 100644
--- a/fs/fcntl.c
+++ b/fs/fcntl.c
@@ -20,6 +20,7 @@
 #include <linux/signal.h>
 #include <linux/rcupdate.h>
 #include <linux/pid_namespace.h>
+#include <linux/user_namespace.h>
 
 #include <asm/poll.h>
 #include <asm/siginfo.h>
@@ -340,6 +341,31 @@ static int f_getown_ex(struct file *filp, unsigned long arg)
 	return ret;
 }
 
+#ifdef CONFIG_CHECKPOINT_RESTORE
+static int f_getowner_uids(struct file *filp, unsigned long arg)
+{
+	struct user_namespace *user_ns = current_user_ns();
+	uid_t * __user dst = (void * __user)arg;
+	uid_t src[2];
+	int err;
+
+	read_lock(&filp->f_owner.lock);
+	src[0] = from_kuid(user_ns, filp->f_owner.uid);
+	src[1] = from_kuid(user_ns, filp->f_owner.euid);
+	read_unlock(&filp->f_owner.lock);
+
+	err  = put_user(src[0], &dst[0]);
+	err |= put_user(src[1], &dst[1]);
+
+	return err;
+}
+#else
+static int f_getowner_uids(struct file *filp, unsigned long arg)
+{
+	return -EINVAL;
+}
+#endif
+
 static long do_fcntl(int fd, unsigned int cmd, unsigned long arg,
 		struct file *filp)
 {
@@ -396,6 +422,9 @@ static long do_fcntl(int fd, unsigned int cmd, unsigned long arg,
 	case F_SETOWN_EX:
 		err = f_setown_ex(filp, arg);
 		break;
+	case F_GETOWNER_UIDS:
+		err = f_getowner_uids(filp, arg);
+		break;
 	case F_GETSIG:
 		err = filp->f_owner.signum;
 		break;
diff --git a/fs/hfsplus/super.c b/fs/hfsplus/super.c
index 47333209801..fdafb2d7165 100644
--- a/fs/hfsplus/super.c
+++ b/fs/hfsplus/super.c
@@ -365,7 +365,7 @@ static int hfsplus_fill_super(struct super_block *sb, void *data, int silent)
 	u64 last_fs_block, last_fs_page;
 	int err;
 
-	err = -EINVAL;
+	err = -ENOMEM;
 	sbi = kzalloc(sizeof(*sbi), GFP_KERNEL);
 	if (!sbi)
 		goto out;
diff --git a/fs/minix/itree_v2.c b/fs/minix/itree_v2.c
index 13487ad1689..78e2d93e5c8 100644
--- a/fs/minix/itree_v2.c
+++ b/fs/minix/itree_v2.c
@@ -32,7 +32,8 @@ static int block_to_path(struct inode * inode, long block, int offsets[DEPTH])
 	if (block < 0) {
 		printk("MINIX-fs: block_to_path: block %ld < 0 on dev %s\n",
 			block, bdevname(sb->s_bdev, b));
-	} else if (block >= (minix_sb(inode->i_sb)->s_max_size/sb->s_blocksize)) {
+	} else if ((u64)block * (u64)sb->s_blocksize >=
+			minix_sb(sb)->s_max_size) {
 		if (printk_ratelimit())
 			printk("MINIX-fs: block_to_path: "
 			       "block %ld too big on dev %s\n",
diff --git a/fs/nilfs2/alloc.h b/fs/nilfs2/alloc.h
index f5fde36b9e2..fb723810054 100644
--- a/fs/nilfs2/alloc.h
+++ b/fs/nilfs2/alloc.h
@@ -76,15 +76,23 @@ int nilfs_palloc_freev(struct inode *, __u64 *, size_t);
 #define nilfs_clear_bit_atomic		ext2_clear_bit_atomic
 #define nilfs_find_next_zero_bit	find_next_zero_bit_le
 
-/*
- * persistent object allocator cache
+/**
+ * struct nilfs_bh_assoc - block offset and buffer head association
+ * @blkoff: block offset
+ * @bh: buffer head
  */
-
 struct nilfs_bh_assoc {
 	unsigned long blkoff;
 	struct buffer_head *bh;
 };
 
+/**
+ * struct nilfs_palloc_cache - persistent object allocator cache
+ * @lock: cache protecting lock
+ * @prev_desc: blockgroup descriptors cache
+ * @prev_bitmap: blockgroup bitmap cache
+ * @prev_entry: translation entries cache
+ */
 struct nilfs_palloc_cache {
 	spinlock_t lock;
 	struct nilfs_bh_assoc prev_desc;
diff --git a/fs/nilfs2/bmap.h b/fs/nilfs2/bmap.h
index 40d9f453d31..b89e68076ad 100644
--- a/fs/nilfs2/bmap.h
+++ b/fs/nilfs2/bmap.h
@@ -135,6 +135,13 @@ struct nilfs_bmap {
 /* state */
 #define NILFS_BMAP_DIRTY	0x00000001
 
+/**
+ * struct nilfs_bmap_store - shadow copy of bmap state
+ * @data: cached raw block mapping of on-disk inode
+ * @last_allocated_key: cached value of last allocated key for data block
+ * @last_allocated_ptr: cached value of last allocated ptr for data block
+ * @state: cached value of state field of bmap structure
+ */
 struct nilfs_bmap_store {
 	__le64 data[NILFS_BMAP_SIZE / sizeof(__le64)];
 	__u64 last_allocated_key;
diff --git a/fs/nilfs2/btnode.h b/fs/nilfs2/btnode.h
index 3a4dd2d8d3f..d876b565ce6 100644
--- a/fs/nilfs2/btnode.h
+++ b/fs/nilfs2/btnode.h
@@ -29,7 +29,13 @@
 #include <linux/fs.h>
 #include <linux/backing-dev.h>
 
-
+/**
+ * struct nilfs_btnode_chkey_ctxt - change key context
+ * @oldkey: old key of block's moving content
+ * @newkey: new key for block's content
+ * @bh: buffer head of old buffer
+ * @newbh: buffer head of new buffer
+ */
 struct nilfs_btnode_chkey_ctxt {
 	__u64 oldkey;
 	__u64 newkey;
diff --git a/fs/nilfs2/cpfile.c b/fs/nilfs2/cpfile.c
index dab5c4c6dfa..deaa3d33a0a 100644
--- a/fs/nilfs2/cpfile.c
+++ b/fs/nilfs2/cpfile.c
@@ -286,7 +286,7 @@ int nilfs_cpfile_delete_checkpoints(struct inode *cpfile,
 	__u64 cno;
 	void *kaddr;
 	unsigned long tnicps;
-	int ret, ncps, nicps, count, i;
+	int ret, ncps, nicps, nss, count, i;
 
 	if (unlikely(start == 0 || start > end)) {
 		printk(KERN_ERR "%s: invalid range of checkpoint numbers: "
@@ -301,6 +301,7 @@ int nilfs_cpfile_delete_checkpoints(struct inode *cpfile,
 	if (ret < 0)
 		goto out_sem;
 	tnicps = 0;
+	nss = 0;
 
 	for (cno = start; cno < end; cno += ncps) {
 		ncps = nilfs_cpfile_checkpoints_in_block(cpfile, cno, end);
@@ -318,8 +319,9 @@ int nilfs_cpfile_delete_checkpoints(struct inode *cpfile,
 			cpfile, cno, cp_bh, kaddr);
 		nicps = 0;
 		for (i = 0; i < ncps; i++, cp = (void *)cp + cpsz) {
-			WARN_ON(nilfs_checkpoint_snapshot(cp));
-			if (!nilfs_checkpoint_invalid(cp)) {
+			if (nilfs_checkpoint_snapshot(cp)) {
+				nss++;
+			} else if (!nilfs_checkpoint_invalid(cp)) {
 				nilfs_checkpoint_set_invalid(cp);
 				nicps++;
 			}
@@ -364,6 +366,8 @@ int nilfs_cpfile_delete_checkpoints(struct inode *cpfile,
 	}
 
 	brelse(header_bh);
+	if (nss > 0)
+		ret = -EBUSY;
 
  out_sem:
 	up_write(&NILFS_MDT(cpfile)->mi_sem);
diff --git a/fs/nilfs2/dat.c b/fs/nilfs2/dat.c
index b5c13f3576b..fa0f80308c2 100644
--- a/fs/nilfs2/dat.c
+++ b/fs/nilfs2/dat.c
@@ -33,6 +33,12 @@
 #define NILFS_CNO_MIN	((__u64)1)
 #define NILFS_CNO_MAX	(~(__u64)0)
 
+/**
+ * struct nilfs_dat_info - on-memory private data of DAT file
+ * @mi: on-memory private data of metadata file
+ * @palloc_cache: persistent object allocator cache of DAT file
+ * @shadow: shadow map of DAT file
+ */
 struct nilfs_dat_info {
 	struct nilfs_mdt_info mi;
 	struct nilfs_palloc_cache palloc_cache;
diff --git a/fs/nilfs2/export.h b/fs/nilfs2/export.h
index a71cc412b65..19ccbf9522a 100644
--- a/fs/nilfs2/export.h
+++ b/fs/nilfs2/export.h
@@ -5,6 +5,14 @@
 
 extern const struct export_operations nilfs_export_ops;
 
+/**
+ * struct nilfs_fid - NILFS file id type
+ * @cno: checkpoint number
+ * @ino: inode number
+ * @gen: file generation (version) for NFS
+ * @parent_gen: parent generation (version) for NFS
+ * @parent_ino: parent inode number
+ */
 struct nilfs_fid {
 	u64 cno;
 	u64 ino;
diff --git a/fs/nilfs2/ifile.c b/fs/nilfs2/ifile.c
index 5a48df79d67..d8e65bde083 100644
--- a/fs/nilfs2/ifile.c
+++ b/fs/nilfs2/ifile.c
@@ -29,7 +29,11 @@
 #include "alloc.h"
 #include "ifile.h"
 
-
+/**
+ * struct nilfs_ifile_info - on-memory private data of ifile
+ * @mi: on-memory private data of metadata file
+ * @palloc_cache: persistent object allocator cache of ifile
+ */
 struct nilfs_ifile_info {
 	struct nilfs_mdt_info mi;
 	struct nilfs_palloc_cache palloc_cache;
diff --git a/fs/nilfs2/inode.c b/fs/nilfs2/inode.c
index 7cc64465ec2..6e2c3db976b 100644
--- a/fs/nilfs2/inode.c
+++ b/fs/nilfs2/inode.c
@@ -34,6 +34,13 @@
 #include "cpfile.h"
 #include "ifile.h"
 
+/**
+ * struct nilfs_iget_args - arguments used during comparison between inodes
+ * @ino: inode number
+ * @cno: checkpoint number
+ * @root: pointer on NILFS root object (mounted checkpoint)
+ * @for_gc: inode for GC flag
+ */
 struct nilfs_iget_args {
 	u64 ino;
 	__u64 cno;
diff --git a/fs/nilfs2/ioctl.c b/fs/nilfs2/ioctl.c
index 06658caa18b..0b6387c67e6 100644
--- a/fs/nilfs2/ioctl.c
+++ b/fs/nilfs2/ioctl.c
@@ -182,7 +182,7 @@ static int nilfs_ioctl_change_cpmode(struct inode *inode, struct file *filp,
 	if (copy_from_user(&cpmode, argp, sizeof(cpmode)))
 		goto out;
 
-	down_read(&inode->i_sb->s_umount);
+	mutex_lock(&nilfs->ns_snapshot_mount_mutex);
 
 	nilfs_transaction_begin(inode->i_sb, &ti, 0);
 	ret = nilfs_cpfile_change_cpmode(
@@ -192,7 +192,7 @@ static int nilfs_ioctl_change_cpmode(struct inode *inode, struct file *filp,
 	else
 		nilfs_transaction_commit(inode->i_sb); /* never fails */
 
-	up_read(&inode->i_sb->s_umount);
+	mutex_unlock(&nilfs->ns_snapshot_mount_mutex);
 out:
 	mnt_drop_write_file(filp);
 	return ret;
diff --git a/fs/nilfs2/mdt.h b/fs/nilfs2/mdt.h
index ab20a4baa50..ab172e8549c 100644
--- a/fs/nilfs2/mdt.h
+++ b/fs/nilfs2/mdt.h
@@ -28,6 +28,13 @@
 #include "nilfs.h"
 #include "page.h"
 
+/**
+ * struct nilfs_shadow_map - shadow mapping of meta data file
+ * @bmap_store: shadow copy of bmap state
+ * @frozen_data: shadowed dirty data pages
+ * @frozen_btnodes: shadowed dirty b-tree nodes' pages
+ * @frozen_buffers: list of frozen buffers
+ */
 struct nilfs_shadow_map {
 	struct nilfs_bmap_store bmap_store;
 	struct address_space frozen_data;
diff --git a/fs/nilfs2/nilfs.h b/fs/nilfs2/nilfs.h
index 250add84da7..74cece80e9a 100644
--- a/fs/nilfs2/nilfs.h
+++ b/fs/nilfs2/nilfs.h
@@ -32,8 +32,21 @@
 #include "the_nilfs.h"
 #include "bmap.h"
 
-/*
- * nilfs inode data in memory
+/**
+ * struct nilfs_inode_info - nilfs inode data in memory
+ * @i_flags: inode flags
+ * @i_state: dynamic state flags
+ * @i_bmap: pointer on i_bmap_data
+ * @i_bmap_data: raw block mapping
+ * @i_xattr: <TODO>
+ * @i_dir_start_lookup: page index of last successful search
+ * @i_cno: checkpoint number for GC inode
+ * @i_btnode_cache: cached pages of b-tree nodes
+ * @i_dirty: list for connecting dirty files
+ * @xattr_sem: semaphore for extended attributes processing
+ * @i_bh: buffer contains disk inode
+ * @i_root: root object of the current filesystem tree
+ * @vfs_inode: VFS inode object
  */
 struct nilfs_inode_info {
 	__u32 i_flags;
diff --git a/fs/nilfs2/sufile.c b/fs/nilfs2/sufile.c
index c5b7653a439..3127e9f438a 100644
--- a/fs/nilfs2/sufile.c
+++ b/fs/nilfs2/sufile.c
@@ -30,7 +30,13 @@
 #include "mdt.h"
 #include "sufile.h"
 
-
+/**
+ * struct nilfs_sufile_info - on-memory private data of sufile
+ * @mi: on-memory private data of metadata file
+ * @ncleansegs: number of clean segments
+ * @allocmin: lower limit of allocatable segment range
+ * @allocmax: upper limit of allocatable segment range
+ */
 struct nilfs_sufile_info {
 	struct nilfs_mdt_info mi;
 	unsigned long ncleansegs;/* number of clean segments */
diff --git a/fs/nilfs2/super.c b/fs/nilfs2/super.c
index d57c42f974e..6522cac6057 100644
--- a/fs/nilfs2/super.c
+++ b/fs/nilfs2/super.c
@@ -677,7 +677,6 @@ static const struct super_operations nilfs_sops = {
 	.destroy_inode  = nilfs_destroy_inode,
 	.dirty_inode    = nilfs_dirty_inode,
 	/* .write_inode    = nilfs_write_inode, */
-	/* .put_inode      = nilfs_put_inode, */
 	/* .drop_inode	  = nilfs_drop_inode, */
 	.evict_inode    = nilfs_evict_inode,
 	.put_super      = nilfs_put_super,
@@ -685,8 +684,6 @@ static const struct super_operations nilfs_sops = {
 	.sync_fs        = nilfs_sync_fs,
 	.freeze_fs	= nilfs_freeze,
 	.unfreeze_fs	= nilfs_unfreeze,
-	/* .write_super_lockfs */
-	/* .unlockfs */
 	.statfs         = nilfs_statfs,
 	.remount_fs     = nilfs_remount,
 	/* .umount_begin */
@@ -948,6 +945,8 @@ static int nilfs_attach_snapshot(struct super_block *s, __u64 cno,
 	struct nilfs_root *root;
 	int ret;
 
+	mutex_lock(&nilfs->ns_snapshot_mount_mutex);
+
 	down_read(&nilfs->ns_segctor_sem);
 	ret = nilfs_cpfile_is_snapshot(nilfs->ns_cpfile, cno);
 	up_read(&nilfs->ns_segctor_sem);
@@ -972,6 +971,7 @@ static int nilfs_attach_snapshot(struct super_block *s, __u64 cno,
 	ret = nilfs_get_root_dentry(s, root, root_dentry);
 	nilfs_put_root(root);
  out:
+	mutex_unlock(&nilfs->ns_snapshot_mount_mutex);
 	return ret;
 }
 
diff --git a/fs/nilfs2/the_nilfs.c b/fs/nilfs2/the_nilfs.c
index 501b7f8b739..41e6a04a561 100644
--- a/fs/nilfs2/the_nilfs.c
+++ b/fs/nilfs2/the_nilfs.c
@@ -76,6 +76,7 @@ struct the_nilfs *alloc_nilfs(struct block_device *bdev)
 	nilfs->ns_bdev = bdev;
 	atomic_set(&nilfs->ns_ndirtyblks, 0);
 	init_rwsem(&nilfs->ns_sem);
+	mutex_init(&nilfs->ns_snapshot_mount_mutex);
 	INIT_LIST_HEAD(&nilfs->ns_dirty_files);
 	INIT_LIST_HEAD(&nilfs->ns_gc_inodes);
 	spin_lock_init(&nilfs->ns_inode_lock);
diff --git a/fs/nilfs2/the_nilfs.h b/fs/nilfs2/the_nilfs.h
index 9992b11312f..6eee4177807 100644
--- a/fs/nilfs2/the_nilfs.h
+++ b/fs/nilfs2/the_nilfs.h
@@ -47,11 +47,13 @@ enum {
  * @ns_flags: flags
  * @ns_bdev: block device
  * @ns_sem: semaphore for shared states
+ * @ns_snapshot_mount_mutex: mutex to protect snapshot mounts
  * @ns_sbh: buffer heads of on-disk super blocks
  * @ns_sbp: pointers to super block data
  * @ns_sbwtime: previous write time of super block
  * @ns_sbwcount: write count of super block
  * @ns_sbsize: size of valid data in super block
+ * @ns_mount_state: file system state
  * @ns_seg_seq: segment sequence counter
  * @ns_segnum: index number of the latest full segment.
  * @ns_nextnum: index number of the full segment index to be used next
@@ -99,6 +101,7 @@ struct the_nilfs {
 
 	struct block_device    *ns_bdev;
 	struct rw_semaphore	ns_sem;
+	struct mutex		ns_snapshot_mount_mutex;
 
 	/*
 	 * used for
@@ -229,9 +232,8 @@ THE_NILFS_FNS(SB_DIRTY, sb_dirty)
  * @count: refcount of this structure
  * @nilfs: nilfs object
  * @ifile: inode file
- * @root: root inode
  * @inodes_count: number of inodes
- * @blocks_count: number of blocks (Reserved)
+ * @blocks_count: number of blocks
  */
 struct nilfs_root {
 	__u64 cno;
diff --git a/fs/ntfs/super.c b/fs/ntfs/super.c
index b341492542c..2bc149d6a78 100644
--- a/fs/ntfs/super.c
+++ b/fs/ntfs/super.c
@@ -2660,31 +2660,14 @@ static const struct super_operations ntfs_sops = {
 	.alloc_inode	= ntfs_alloc_big_inode,	  /* VFS: Allocate new inode. */
 	.destroy_inode	= ntfs_destroy_big_inode, /* VFS: Deallocate inode. */
 #ifdef NTFS_RW
-	//.dirty_inode	= NULL,			/* VFS: Called from
-	//					   __mark_inode_dirty(). */
 	.write_inode	= ntfs_write_inode,	/* VFS: Write dirty inode to
 						   disk. */
-	//.drop_inode	= NULL,			/* VFS: Called just after the
-	//					   inode reference count has
-	//					   been decreased to zero.
-	//					   NOTE: The inode lock is
-	//					   held. See fs/inode.c::
-	//					   generic_drop_inode(). */
-	//.delete_inode	= NULL,			/* VFS: Delete inode from disk.
-	//					   Called when i_count becomes
-	//					   0 and i_nlink is also 0. */
-	//.write_super	= NULL,			/* Flush dirty super block to
-	//					   disk. */
-	//.sync_fs	= NULL,			/* ? */
-	//.write_super_lockfs	= NULL,		/* ? */
-	//.unlockfs	= NULL,			/* ? */
 #endif /* NTFS_RW */
 	.put_super	= ntfs_put_super,	/* Syscall: umount. */
 	.statfs		= ntfs_statfs,		/* Syscall: statfs */
 	.remount_fs	= ntfs_remount,		/* Syscall: mount -o remount. */
 	.evict_inode	= ntfs_evict_big_inode,	/* VFS: Called when an inode is
 						   removed from memory. */
-	//.umount_begin	= NULL,			/* Forced umount. */
 	.show_options	= ntfs_show_options,	/* Show mount options in
 						   proc. */
 };
diff --git a/fs/ocfs2/localalloc.c b/fs/ocfs2/localalloc.c
index 210c3523754..a9f78c74d68 100644
--- a/fs/ocfs2/localalloc.c
+++ b/fs/ocfs2/localalloc.c
@@ -784,14 +784,10 @@ bail:
 
 static u32 ocfs2_local_alloc_count_bits(struct ocfs2_dinode *alloc)
 {
-	int i;
-	u8 *buffer;
-	u32 count = 0;
+	u32 count;
 	struct ocfs2_local_alloc *la = OCFS2_LOCAL_ALLOC(alloc);
 
-	buffer = la->la_bitmap;
-	for (i = 0; i < le16_to_cpu(la->la_size); i++)
-		count += hweight8(buffer[i]);
+	count = memweight(la->la_bitmap, le16_to_cpu(la->la_size));
 
 	trace_ocfs2_local_alloc_count_bits(count);
 	return count;
diff --git a/fs/proc/base.c b/fs/proc/base.c
index 2772208338f..1b6c84cbdb7 100644
--- a/fs/proc/base.c
+++ b/fs/proc/base.c
@@ -695,8 +695,6 @@ static int __mem_open(struct inode *inode, struct file *file, unsigned int mode)
 		mmput(mm);
 	}
 
-	/* OK to pass negative loff_t, we can catch out-of-range */
-	file->f_mode |= FMODE_UNSIGNED_OFFSET;
 	file->private_data = mm;
 
 	return 0;
@@ -704,7 +702,12 @@ static int __mem_open(struct inode *inode, struct file *file, unsigned int mode)
 
 static int mem_open(struct inode *inode, struct file *file)
 {
-	return __mem_open(inode, file, PTRACE_MODE_ATTACH);
+	int ret = __mem_open(inode, file, PTRACE_MODE_ATTACH);
+
+	/* OK to pass negative loff_t, we can catch out-of-range */
+	file->f_mode |= FMODE_UNSIGNED_OFFSET;
+
+	return ret;
 }
 
 static ssize_t mem_rw(struct file *file, char __user *buf,
@@ -827,15 +830,16 @@ static ssize_t environ_read(struct file *file, char __user *buf,
 	if (!atomic_inc_not_zero(&mm->mm_users))
 		goto free;
 	while (count > 0) {
-		int this_len, retval, max_len;
-
-		this_len = mm->env_end - (mm->env_start + src);
+		size_t this_len, max_len;
+		int retval;
 
-		if (this_len <= 0)
+		if (src >= (mm->env_end - mm->env_start))
 			break;
 
-		max_len = (count > PAGE_SIZE) ? PAGE_SIZE : count;
-		this_len = (this_len > max_len) ? max_len : this_len;
+		this_len = mm->env_end - (mm->env_start + src);
+
+		max_len = min_t(size_t, PAGE_SIZE, count);
+		this_len = min(max_len, this_len);
 
 		retval = access_remote_vm(mm, (mm->env_start + src),
 			page, this_len, 0);
diff --git a/fs/qnx4/bitmap.c b/fs/qnx4/bitmap.c
index 22e0d60e53e..76a7a697b77 100644
--- a/fs/qnx4/bitmap.c
+++ b/fs/qnx4/bitmap.c
@@ -17,23 +17,6 @@
 #include <linux/bitops.h>
 #include "qnx4.h"
 
-static void count_bits(register const char *bmPart, register int size,
-		       int *const tf)
-{
-	char b;
-	int tot = *tf;
-
-	if (size > QNX4_BLOCK_SIZE) {
-		size = QNX4_BLOCK_SIZE;
-	}
-	do {
-		b = *bmPart++;
-		tot += 8 - hweight8(b);
-		size--;
-	} while (size != 0);
-	*tf = tot;
-}
-
 unsigned long qnx4_count_free_blocks(struct super_block *sb)
 {
 	int start = le32_to_cpu(qnx4_sb(sb)->BitMap->di_first_xtnt.xtnt_blk) - 1;
@@ -44,13 +27,16 @@ unsigned long qnx4_count_free_blocks(struct super_block *sb)
 	struct buffer_head *bh;
 
 	while (total < size) {
+		int bytes = min(size - total, QNX4_BLOCK_SIZE);
+
 		if ((bh = sb_bread(sb, start + offset)) == NULL) {
 			printk(KERN_ERR "qnx4: I/O error in counting free blocks\n");
 			break;
 		}
-		count_bits(bh->b_data, size - total, &total_free);
+		total_free += bytes * BITS_PER_BYTE -
+				memweight(bh->b_data, bytes);
 		brelse(bh);
-		total += QNX4_BLOCK_SIZE;
+		total += bytes;
 		offset++;
 	}
 
diff --git a/fs/xattr.c b/fs/xattr.c
index 1d7ac379045..4d45b7189e7 100644
--- a/fs/xattr.c
+++ b/fs/xattr.c
@@ -427,6 +427,7 @@ getxattr(struct dentry *d, const char __user *name, void __user *value,
 {
 	ssize_t error;
 	void *kvalue = NULL;
+	void *vvalue = NULL;
 	char kname[XATTR_NAME_MAX + 1];
 
 	error = strncpy_from_user(kname, name, sizeof(kname));
@@ -438,9 +439,13 @@ getxattr(struct dentry *d, const char __user *name, void __user *value,
 	if (size) {
 		if (size > XATTR_SIZE_MAX)
 			size = XATTR_SIZE_MAX;
-		kvalue = kzalloc(size, GFP_KERNEL);
-		if (!kvalue)
-			return -ENOMEM;
+		kvalue = kzalloc(size, GFP_KERNEL | __GFP_NOWARN);
+		if (!kvalue) {
+			vvalue = vmalloc(size);
+			if (!vvalue)
+				return -ENOMEM;
+			kvalue = vvalue;
+		}
 	}
 
 	error = vfs_getxattr(d, kname, kvalue, size);
@@ -452,7 +457,10 @@ getxattr(struct dentry *d, const char __user *name, void __user *value,
 		   than XATTR_SIZE_MAX bytes. Not possible. */
 		error = -E2BIG;
 	}
-	kfree(kvalue);
+	if (vvalue)
+		vfree(vvalue);
+	else
+		kfree(kvalue);
 	return error;
 }