[GFS2] Make journaled data files identical to normal files on disk

This is a very large patch, with a few still to be resolved issues
so you might want to check out the previous head of the tree since
this is known to be unstable. Fixes for the various bugs will be
forthcoming shortly.

This patch removes the special data format which has been used
up till now for journaled data files. Directories still retain the
old format so that they will remain on disk compatible with earlier
releases. As a result you can now do the following with journaled
data files:

 1) mmap them
 2) export them over NFS
 3) convert to/from normal files whenever you want to (the zero length
    restriction is gone)

In addition the level at which GFS' locking is done has changed for all
files (since they all now use the page cache) such that the locking is
done at the page cache level rather than the level of the fs operations.
This should mean that things like loopback mounts and other things which
touch the page cache directly should now work.

Current known issues:

 1. There is a lock mode inversion problem related to the resource
    group hold function which needs to be resolved.
 2. Any significant amount of I/O causes an oops with an offset of hex 320
    (NULL pointer dereference) which appears to be related to a journaled data
    buffer appearing on a list where it shouldn't be.
 3. Direct I/O writes are disabled for the time being (will reappear later)
 4. There is probably a deadlock between the page lock and GFS' locks under
    certain combinations of mmap and fs operation I/O.
 5. Issue relating to ref counting on internally used inodes causes a hang
    on umount (discovered before this patch, and not fixed by it)
 6. One part of the directory metadata is different from GFS1 and will need
    to be resolved before next release.

Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>

1 files changed, 164 insertions, 803 deletions

diff --git a/fs/gfs2/ops_file.c b/fs/gfs2/ops_file.c
index 0f356fc4690..56820b39a99 100644
--- a/fs/gfs2/ops_file.c
+++ b/fs/gfs2/ops_file.c
@@ -18,6 +18,7 @@
 #include <linux/mm.h>
 #include <linux/smp_lock.h>
 #include <linux/gfs2_ioctl.h>
+#include <linux/fs.h>
 #include <asm/semaphore.h>
 #include <asm/uaccess.h>
 
@@ -27,7 +28,6 @@
 #include "glock.h"
 #include "glops.h"
 #include "inode.h"
-#include "jdata.h"
 #include "lm.h"
 #include "log.h"
 #include "meta_io.h"
@@ -67,10 +67,37 @@ struct filldir_reg {
 	void *fdr_opaque;
 };
 
-typedef ssize_t(*do_rw_t) (struct file *file,
-		   char __user *buf,
-		   size_t size, loff_t *offset,
-		   unsigned int num_gh, struct gfs2_holder *ghs);
+static int gfs2_read_actor(read_descriptor_t *desc, struct page *page,
+			   unsigned long offset, unsigned long size)
+{
+	char *kaddr;
+	unsigned long count = desc->count;
+
+	if (size > count)
+		size = count;
+
+	kaddr = kmap(page);
+	memcpy(desc->arg.buf, kaddr + offset, size);
+        kunmap(page);
+
+        desc->count = count - size;
+        desc->written += size;
+        desc->arg.buf += size;
+        return size;
+}
+
+int gfs2_internal_read(struct gfs2_inode *ip, struct file_ra_state *ra_state,
+		       char *buf, loff_t *pos, unsigned size)
+{
+	struct inode *inode = ip->i_vnode;
+	read_descriptor_t desc;
+	desc.written = 0;
+	desc.arg.buf = buf;
+	desc.count = size;
+	desc.error = 0;
+	do_generic_mapping_read(inode->i_mapping, ra_state, NULL, pos, &desc, gfs2_read_actor);
+	return desc.written ? desc.written : desc.error;
+}
 
 /**
  * gfs2_llseek - seek to a location in a file
@@ -105,247 +132,114 @@ static loff_t gfs2_llseek(struct file *file, loff_t offset, int origin)
 	return error;
 }
 
-static inline unsigned int vma2state(struct vm_area_struct *vma)
-{
-	if ((vma->vm_flags & (VM_MAYWRITE | VM_MAYSHARE)) ==
-	    (VM_MAYWRITE | VM_MAYSHARE))
-		return LM_ST_EXCLUSIVE;
-	return LM_ST_SHARED;
-}
 
-static ssize_t walk_vm_hard(struct file *file, const char __user *buf, size_t size,
-		    loff_t *offset, do_rw_t operation)
+static ssize_t gfs2_direct_IO_read(struct kiocb *iocb, const struct iovec *iov,
+				   loff_t offset, unsigned long nr_segs)
 {
-	struct gfs2_holder *ghs;
-	unsigned int num_gh = 0;
-	ssize_t count;
-	struct super_block *sb = file->f_dentry->d_inode->i_sb;
-	struct mm_struct *mm = current->mm;
-	struct vm_area_struct *vma;
-	unsigned long start = (unsigned long)buf;
-	unsigned long end = start + size;
-	int dumping = (current->flags & PF_DUMPCORE);
-	unsigned int x = 0;
-
-	for (vma = find_vma(mm, start); vma; vma = vma->vm_next) {
-		if (end <= vma->vm_start)
-			break;
-		if (vma->vm_file &&
-		    vma->vm_file->f_dentry->d_inode->i_sb == sb) {
-			num_gh++;
-		}
-	}
-
-	ghs = kcalloc((num_gh + 1), sizeof(struct gfs2_holder), GFP_KERNEL);
-	if (!ghs) {
-		if (!dumping)
-			up_read(&mm->mmap_sem);
-		return -ENOMEM;
-	}
+	struct file *file = iocb->ki_filp;
+	struct address_space *mapping = file->f_mapping;
+	ssize_t retval;
 
-	for (vma = find_vma(mm, start); vma; vma = vma->vm_next) {
-		if (end <= vma->vm_start)
-			break;
-		if (vma->vm_file) {
-			struct inode *inode = vma->vm_file->f_dentry->d_inode;
-			if (inode->i_sb == sb)
-				gfs2_holder_init(get_v2ip(inode)->i_gl,
-						 vma2state(vma), 0, &ghs[x++]);
-		}
+	retval = filemap_write_and_wait(mapping);
+	if (retval == 0) {
+		retval = mapping->a_ops->direct_IO(READ, iocb, iov, offset,
+						   nr_segs);
 	}
-
-	if (!dumping)
-		up_read(&mm->mmap_sem);
-
-	gfs2_assert(get_v2sdp(sb), x == num_gh);
-
-	count = operation(file, buf, size, offset, num_gh, ghs);
-
-	while (num_gh--)
-		gfs2_holder_uninit(&ghs[num_gh]);
-	kfree(ghs);
-
-	return count;
+	return retval;
 }
 
 /**
- * walk_vm - Walk the vmas associated with a buffer for read or write.
- *    If any of them are gfs2, pass the gfs2 inode down to the read/write
- *    worker function so that locks can be acquired in the correct order.
- * @file: The file to read/write from/to
- * @buf: The buffer to copy to/from
- * @size: The amount of data requested
- * @offset: The current file offset
- * @operation: The read or write worker function
- *
- * Outputs: Offset - updated according to number of bytes written
- *
- * Returns: The number of bytes written, errno on failure
+ * __gfs2_file_aio_read - The main GFS2 read function
+ * 
+ * N.B. This is almost, but not quite the same as __generic_file_aio_read()
+ * the important subtle different being that inode->i_size isn't valid
+ * unless we are holding a lock, and we do this _only_ on the O_DIRECT
+ * path since otherwise locking is done entirely at the page cache
+ * layer.
  */
-
-static ssize_t walk_vm(struct file *file, const char __user *buf, size_t size,
-	       loff_t *offset, do_rw_t operation)
+static ssize_t __gfs2_file_aio_read(struct kiocb *iocb,
+				    const struct iovec *iov,
+				    unsigned long nr_segs, loff_t *ppos)
 {
+	struct file *filp = iocb->ki_filp;
+	struct gfs2_inode *ip = get_v2ip(filp->f_mapping->host);
 	struct gfs2_holder gh;
-
-	if (current->mm) {
-		struct super_block *sb = file->f_dentry->d_inode->i_sb;
-		struct mm_struct *mm = current->mm;
-		struct vm_area_struct *vma;
-		unsigned long start = (unsigned long)buf;
-		unsigned long end = start + size;
-		int dumping = (current->flags & PF_DUMPCORE);
-
-		if (!dumping)
-			down_read(&mm->mmap_sem);
-
-		for (vma = find_vma(mm, start); vma; vma = vma->vm_next) {
-			if (end <= vma->vm_start)
-				break;
-			if (vma->vm_file &&
-			    vma->vm_file->f_dentry->d_inode->i_sb == sb)
-				goto do_locks;
-		}
-
-		if (!dumping)
-			up_read(&mm->mmap_sem);
-	}
-
-	return operation(file, buf, size, offset, 0, &gh);
-
-do_locks:
-	return walk_vm_hard(file, buf, size, offset, operation);
-}
-
-static ssize_t do_jdata_read(struct file *file, char __user *buf, size_t size,
-			     loff_t *offset)
-{
-	struct gfs2_inode *ip = get_v2ip(file->f_mapping->host);
-	ssize_t count = 0;
-
-	if (*offset < 0)
+	ssize_t retval;
+	unsigned long seg;
+	size_t count;
+
+	count = 0;
+	for (seg = 0; seg < nr_segs; seg++) {
+		const struct iovec *iv = &iov[seg];
+
+		/*
+		 * If any segment has a negative length, or the cumulative
+		 * length ever wraps negative then return -EINVAL.
+		 */
+	count += iv->iov_len;
+	if (unlikely((ssize_t)(count|iv->iov_len) < 0))
 		return -EINVAL;
-	if (!access_ok(VERIFY_WRITE, buf, size))
+	if (access_ok(VERIFY_WRITE, iv->iov_base, iv->iov_len))
+		continue;
+	if (seg == 0)
 		return -EFAULT;
+	nr_segs = seg;
+	count -= iv->iov_len;   /* This segment is no good */
+	break;
+	}
+
+	/* coalesce the iovecs and go direct-to-BIO for O_DIRECT */
+	if (filp->f_flags & O_DIRECT) {
+		loff_t pos = *ppos, size;
+		struct address_space *mapping;
+		struct inode *inode;
+
+		mapping = filp->f_mapping;
+		inode = mapping->host;
+		retval = 0;
+		if (!count)
+			goto out; /* skip atime */
+
+		gfs2_holder_init(ip->i_gl, LM_ST_SHARED, GL_ATIME, &gh);
+		retval = gfs2_glock_nq_m_atime(1, &gh);
+		if (retval)
+			goto out;
 
-	if (!(file->f_flags & O_LARGEFILE)) {
-		if (*offset >= MAX_NON_LFS)
-			return -EFBIG;
-		if (*offset + size > MAX_NON_LFS)
-			size = MAX_NON_LFS - *offset;
-	}
-
-	count = gfs2_jdata_read(ip, buf, *offset, size, gfs2_copy2user);
-
-	if (count > 0)
-		*offset += count;
-
-	return count;
-}
-
-/**
- * do_read_direct - Read bytes from a file
- * @file: The file to read from
- * @buf: The buffer to copy into
- * @size: The amount of data requested
- * @offset: The current file offset
- * @num_gh: The number of other locks we need to do the read
- * @ghs: the locks we need plus one for our lock
- *
- * Outputs: Offset - updated according to number of bytes read
- *
- * Returns: The number of bytes read, errno on failure
- */
-
-static ssize_t do_read_direct(struct file *file, char __user *buf, size_t size,
-			      loff_t *offset, unsigned int num_gh,
-			      struct gfs2_holder *ghs)
-{
-	struct inode *inode = file->f_mapping->host;
-	struct gfs2_inode *ip = get_v2ip(inode);
-	unsigned int state = LM_ST_DEFERRED;
-	int flags = 0;
-	unsigned int x;
-	ssize_t count = 0;
-	int error;
-
-	for (x = 0; x < num_gh; x++)
-		if (ghs[x].gh_gl == ip->i_gl) {
-			state = LM_ST_SHARED;
-			flags |= GL_LOCAL_EXCL;
-			break;
+		size = i_size_read(inode);
+		if (pos < size) {
+			 retval = gfs2_direct_IO_read(iocb, iov, pos, nr_segs);
+			if (retval > 0 && !is_sync_kiocb(iocb))
+				retval = -EIOCBQUEUED;
+			if (retval > 0)
+				*ppos = pos + retval;
 		}
-
-	gfs2_holder_init(ip->i_gl, state, flags, &ghs[num_gh]);
-
-	error = gfs2_glock_nq_m(num_gh + 1, ghs);
-	if (error)
+		file_accessed(filp);
+		gfs2_glock_dq_m(1, &gh);
+		gfs2_holder_uninit(&gh);
 		goto out;
+	}
 
-	error = -EINVAL;
-	if (gfs2_is_jdata(ip))
-		goto out_gunlock;
-
-	if (gfs2_is_stuffed(ip)) {
-		size_t mask = bdev_hardsect_size(inode->i_sb->s_bdev) - 1;
-
-		if (((*offset) & mask) || (((unsigned long)buf) & mask))
-			goto out_gunlock;
-
-		count = do_jdata_read(file, buf, size & ~mask, offset);
-	} else
-		count = generic_file_read(file, buf, size, offset);
-
-	error = 0;
-
- out_gunlock:
-	gfs2_glock_dq_m(num_gh + 1, ghs);
-
- out:
-	gfs2_holder_uninit(&ghs[num_gh]);
-
-	return (count) ? count : error;
-}
-
-/**
- * do_read_buf - Read bytes from a file
- * @file: The file to read from
- * @buf: The buffer to copy into
- * @size: The amount of data requested
- * @offset: The current file offset
- * @num_gh: The number of other locks we need to do the read
- * @ghs: the locks we need plus one for our lock
- *
- * Outputs: Offset - updated according to number of bytes read
- *
- * Returns: The number of bytes read, errno on failure
- */
-
-static ssize_t do_read_buf(struct file *file, char __user *buf, size_t size,
-			   loff_t *offset, unsigned int num_gh,
-			   struct gfs2_holder *ghs)
-{
-	struct gfs2_inode *ip = get_v2ip(file->f_mapping->host);
-	ssize_t count = 0;
-	int error;
-
-	gfs2_holder_init(ip->i_gl, LM_ST_SHARED, GL_ATIME, &ghs[num_gh]);
-
-	error = gfs2_glock_nq_m_atime(num_gh + 1, ghs);
-	if (error)
-		goto out;
-
-	if (gfs2_is_jdata(ip))
-		count = do_jdata_read(file, buf, size, offset);
-	else
-		count = generic_file_read(file, buf, size, offset);
-
-	gfs2_glock_dq_m(num_gh + 1, ghs);
-
- out:
-	gfs2_holder_uninit(&ghs[num_gh]);
-
-	return (count) ? count : error;
+	retval = 0;
+	if (count) {
+		for (seg = 0; seg < nr_segs; seg++) {
+			read_descriptor_t desc;
+
+			desc.written = 0;
+			desc.arg.buf = iov[seg].iov_base;
+			desc.count = iov[seg].iov_len;
+			if (desc.count == 0)
+				continue;
+			desc.error = 0;
+			do_generic_file_read(filp,ppos,&desc,file_read_actor);
+			retval += desc.written;
+			if (desc.error) {
+				retval = retval ?: desc.error;
+				 break;
+			}
+		}
+	}
+out:
+	return retval;
 }
 
 /**
@@ -360,550 +254,49 @@ static ssize_t do_read_buf(struct file *file, char __user *buf, size_t size,
  * Returns: The number of bytes read, errno on failure
  */
 
-static ssize_t gfs2_read(struct file *file, char __user *buf, size_t size,
+static ssize_t gfs2_read(struct file *filp, char __user *buf, size_t size,
 			 loff_t *offset)
 {
-	atomic_inc(&get_v2sdp(file->f_mapping->host->i_sb)->sd_ops_file);
-
-	if (file->f_flags & O_DIRECT)
-		return walk_vm(file, buf, size, offset, do_read_direct);
-	else
-		return walk_vm(file, buf, size, offset, do_read_buf);
-}
-
-/**
- * grope_mapping - feel up a mapping that needs to be written
- * @buf: the start of the memory to be written
- * @size: the size of the memory to be written
- *
- * We do this after acquiring the locks on the mapping,
- * but before starting the write transaction.  We need to make
- * sure that we don't cause recursive transactions if blocks
- * need to be allocated to the file backing the mapping.
- *
- * Returns: errno
- */
-
-static int grope_mapping(const char __user *buf, size_t size)
-{
-	const char __user *stop = buf + size;
-	char c;
-
-	while (buf < stop) {
-		if (copy_from_user(&c, buf, 1))
-			return -EFAULT;
-		buf += PAGE_CACHE_SIZE;
-		buf = (const char __user *)PAGE_ALIGN((unsigned long)buf);
-	}
-
-	return 0;
-}
-
-/**
- * do_write_direct_alloc - Write bytes to a file
- * @file: The file to write to
- * @buf: The buffer to copy from
- * @size: The amount of data requested
- * @offset: The current file offset
- *
- * Outputs: Offset - updated according to number of bytes written
- *
- * Returns: The number of bytes written, errno on failure
- */
-
-static ssize_t do_write_direct_alloc(struct file *file, const char __user *buf, size_t size,
-				     loff_t *offset)
-{
-	struct inode *inode = file->f_mapping->host;
-	struct gfs2_inode *ip = get_v2ip(inode);
-	struct gfs2_sbd *sdp = ip->i_sbd;
-	struct gfs2_alloc *al = NULL;
 	struct iovec local_iov = { .iov_base = buf, .iov_len = size };
-	struct buffer_head *dibh;
-	unsigned int data_blocks, ind_blocks;
-	ssize_t count;
-	int error;
-
-	gfs2_write_calc_reserv(ip, size, &data_blocks, &ind_blocks);
-
-	al = gfs2_alloc_get(ip);
-
-	error = gfs2_quota_lock(ip, NO_QUOTA_CHANGE, NO_QUOTA_CHANGE);
-	if (error)
-		goto fail;
-
-	error = gfs2_quota_check(ip, ip->i_di.di_uid, ip->i_di.di_gid);
-	if (error)
-		goto fail_gunlock_q;
-
-	al->al_requested = data_blocks + ind_blocks;
-
-	error = gfs2_inplace_reserve(ip);
-	if (error)
-		goto fail_gunlock_q;
-
-	error = gfs2_trans_begin(sdp,
-				 al->al_rgd->rd_ri.ri_length + ind_blocks +
-				 RES_DINODE + RES_STATFS + RES_QUOTA, 0);
-	if (error)
-		goto fail_ipres;
-
-	if ((ip->i_di.di_mode & (S_ISUID | S_ISGID)) && !capable(CAP_FSETID)) {
-		error = gfs2_meta_inode_buffer(ip, &dibh);
-		if (error)
-			goto fail_end_trans;
-
-		ip->i_di.di_mode &= (ip->i_di.di_mode & S_IXGRP) ?
-			(~(S_ISUID | S_ISGID)) : (~S_ISUID);
-
-		gfs2_trans_add_bh(ip->i_gl, dibh, 1);
-		gfs2_dinode_out(&ip->i_di, dibh->b_data);
-		brelse(dibh);
-	}
-
-	if (gfs2_is_stuffed(ip)) {
-		error = gfs2_unstuff_dinode(ip, gfs2_unstuffer_sync, NULL);
-		if (error)
-			goto fail_end_trans;
-	}
-
-	count = generic_file_write_nolock(file, &local_iov, 1, offset);
-	if (count < 0) {
-		error = count;
-		goto fail_end_trans;
-	}
-
-	error = gfs2_meta_inode_buffer(ip, &dibh);
-	if (error)
-		goto fail_end_trans;
-
-	if (ip->i_di.di_size < inode->i_size)
-		ip->i_di.di_size = inode->i_size;
-	ip->i_di.di_mtime = ip->i_di.di_ctime = get_seconds();
-
-	gfs2_trans_add_bh(ip->i_gl, dibh, 1);
-	gfs2_dinode_out(&ip->i_di, dibh->b_data);
-	brelse(dibh);
-
-	gfs2_trans_end(sdp);
+	struct kiocb kiocb;
+	ssize_t ret;
 
-	if (file->f_flags & O_SYNC)
-		gfs2_log_flush_glock(ip->i_gl);
-
-	gfs2_inplace_release(ip);
-	gfs2_quota_unlock(ip);
-	gfs2_alloc_put(ip);
-
-	if (file->f_mapping->nrpages) {
-		error = filemap_fdatawrite(file->f_mapping);
-		if (!error)
-			error = filemap_fdatawait(file->f_mapping);
-	}
-	if (error)
-		return error;
-
-	return count;
-
- fail_end_trans:
-	gfs2_trans_end(sdp);
-
- fail_ipres:
-	gfs2_inplace_release(ip);
-
- fail_gunlock_q:
-	gfs2_quota_unlock(ip);
-
- fail:
-	gfs2_alloc_put(ip);
+	atomic_inc(&get_v2sdp(filp->f_mapping->host->i_sb)->sd_ops_file);
 
-	return error;
-}
-
-/**
- * do_write_direct - Write bytes to a file
- * @file: The file to write to
- * @buf: The buffer to copy from
- * @size: The amount of data requested
- * @offset: The current file offset
- * @num_gh: The number of other locks we need to do the read
- * @gh: the locks we need plus one for our lock
- *
- * Outputs: Offset - updated according to number of bytes written
- *
- * Returns: The number of bytes written, errno on failure
- */
-
-static ssize_t do_write_direct(struct file *file, const char __user *buf, size_t size,
-			       loff_t *offset, unsigned int num_gh,
-			       struct gfs2_holder *ghs)
-{
-	struct gfs2_inode *ip = get_v2ip(file->f_mapping->host);
-	struct gfs2_sbd *sdp = ip->i_sbd;
-	struct gfs2_file *fp = get_v2fp(file);
-	unsigned int state = LM_ST_DEFERRED;
-	int alloc_required;
-	unsigned int x;
-	size_t s;
-	ssize_t count = 0;
-	int error;
-
-	if (test_bit(GFF_DID_DIRECT_ALLOC, &fp->f_flags))
-		state = LM_ST_EXCLUSIVE;
-	else
-		for (x = 0; x < num_gh; x++)
-			if (ghs[x].gh_gl == ip->i_gl) {
-				state = LM_ST_EXCLUSIVE;
-				break;
-			}
-
- restart:
-	gfs2_holder_init(ip->i_gl, state, 0, &ghs[num_gh]);
-
-	error = gfs2_glock_nq_m(num_gh + 1, ghs);
-	if (error)
-		goto out;
-
-	error = -EINVAL;
-	if (gfs2_is_jdata(ip))
-		goto out_gunlock;
-
-	if (num_gh) {
-		error = grope_mapping(buf, size);
-		if (error)
-			goto out_gunlock;
-	}
-
-	if (file->f_flags & O_APPEND)
-		*offset = ip->i_di.di_size;
-
-	if (!(file->f_flags & O_LARGEFILE)) {
-		error = -EFBIG;
-		if (*offset >= MAX_NON_LFS)
-			goto out_gunlock;
-		if (*offset + size > MAX_NON_LFS)
-			size = MAX_NON_LFS - *offset;
-	}
-
-	if (gfs2_is_stuffed(ip) ||
-	    *offset + size > ip->i_di.di_size ||
-	    ((ip->i_di.di_mode & (S_ISUID | S_ISGID)) && !capable(CAP_FSETID)))
-		alloc_required = 1;
-	else {
-		error = gfs2_write_alloc_required(ip, *offset, size,
-						 &alloc_required);
-		if (error)
-			goto out_gunlock;
-	}
-
-	if (alloc_required && state != LM_ST_EXCLUSIVE) {
-		gfs2_glock_dq_m(num_gh + 1, ghs);
-		gfs2_holder_uninit(&ghs[num_gh]);
-		state = LM_ST_EXCLUSIVE;
-		goto restart;
-	}
-
-	if (alloc_required) {
-		set_bit(GFF_DID_DIRECT_ALLOC, &fp->f_flags);
-
-		/* split large writes into smaller atomic transactions */
-		while (size) {
-			s = gfs2_tune_get(sdp, gt_max_atomic_write);
-			if (s > size)
-				s = size;
-
-			error = do_write_direct_alloc(file, buf, s, offset);
-			if (error < 0)
-				goto out_gunlock;
-
-			buf += error;
-			size -= error;
-			count += error;
-		}
-	} else {
-		struct iovec local_iov = { .iov_base = buf, .iov_len = size };
-		struct gfs2_holder t_gh;
-
-		clear_bit(GFF_DID_DIRECT_ALLOC, &fp->f_flags);
-
-		error = gfs2_glock_nq_init(sdp->sd_trans_gl, LM_ST_SHARED,
-					   GL_NEVER_RECURSE, &t_gh);
-		if (error)
-			goto out_gunlock;
-
-		count = generic_file_write_nolock(file, &local_iov, 1, offset);
-
-		gfs2_glock_dq_uninit(&t_gh);
-	}
-
-	error = 0;
-
- out_gunlock:
-	gfs2_glock_dq_m(num_gh + 1, ghs);
-
- out:
-	gfs2_holder_uninit(&ghs[num_gh]);
-
-	return (count) ? count : error;
+	init_sync_kiocb(&kiocb, filp);
+	ret = __gfs2_file_aio_read(&kiocb, &local_iov, 1, offset);
+	if (-EIOCBQUEUED == ret)
+		ret = wait_on_sync_kiocb(&kiocb);
+	return ret;
 }
 
-/**
- * do_do_write_buf - Write bytes to a file
- * @file: The file to write to
- * @buf: The buffer to copy from
- * @size: The amount of data requested
- * @offset: The current file offset
- *
- * Outputs: Offset - updated according to number of bytes written
- *
- * Returns: The number of bytes written, errno on failure
- */
-
-static ssize_t do_do_write_buf(struct file *file, const char __user *buf, size_t size,
-			       loff_t *offset)
+static ssize_t gfs2_file_readv(struct file *filp, const struct iovec *iov,
+			       unsigned long nr_segs, loff_t *ppos)
 {
-	struct inode *inode = file->f_mapping->host;
-	struct gfs2_inode *ip = get_v2ip(inode);
-	struct gfs2_sbd *sdp = ip->i_sbd;
-	struct gfs2_alloc *al = NULL;
-	struct buffer_head *dibh;
-	unsigned int data_blocks, ind_blocks;
-	int alloc_required, journaled;
-	ssize_t count;
-	int error;
-
-	journaled = gfs2_is_jdata(ip);
-
-	gfs2_write_calc_reserv(ip, size, &data_blocks, &ind_blocks);
-
-	error = gfs2_write_alloc_required(ip, *offset, size, &alloc_required);
-	if (error)
-		return error;
-
-	if (alloc_required) {
-		al = gfs2_alloc_get(ip);
-
-		error = gfs2_quota_lock(ip, NO_QUOTA_CHANGE, NO_QUOTA_CHANGE);
-		if (error)
-			goto fail;
-
-		error = gfs2_quota_check(ip, ip->i_di.di_uid, ip->i_di.di_gid);
-		if (error)
-			goto fail_gunlock_q;
-
-		al->al_requested = data_blocks + ind_blocks;
-
-		error = gfs2_inplace_reserve(ip);
-		if (error)
-			goto fail_gunlock_q;
-
-		error = gfs2_trans_begin(sdp,
-					 al->al_rgd->rd_ri.ri_length +
-					 ind_blocks +
-					 ((journaled) ? data_blocks : 0) +
-					 RES_DINODE + RES_STATFS + RES_QUOTA,
-					 0);
-		if (error)
-			goto fail_ipres;
-	} else {
-		error = gfs2_trans_begin(sdp,
-					((journaled) ? data_blocks : 0) +
-					RES_DINODE,
-					0);
-		if (error)
-			goto fail_ipres;
-	}
-
-	if ((ip->i_di.di_mode & (S_ISUID | S_ISGID)) && !capable(CAP_FSETID)) {
-		error = gfs2_meta_inode_buffer(ip, &dibh);
-		if (error)
-			goto fail_end_trans;
-
-		ip->i_di.di_mode &= (ip->i_di.di_mode & S_IXGRP) ?
-					  (~(S_ISUID | S_ISGID)) : (~S_ISUID);
-
-		gfs2_trans_add_bh(ip->i_gl, dibh, 1);
-		gfs2_dinode_out(&ip->i_di, dibh->b_data);
-		brelse(dibh);
-	}
+	struct kiocb kiocb;
+	ssize_t ret;
 
-	if (journaled) {
-		count = gfs2_jdata_write(ip, buf, *offset, size,
-					 gfs2_copy_from_user);
-		if (count < 0) {
-			error = count;
-			goto fail_end_trans;
-		}
-
-		*offset += count;
-	} else {
-		struct iovec local_iov = { .iov_base = buf, .iov_len = size };
-
-		count = generic_file_write_nolock(file, &local_iov, 1, offset);
-		if (count < 0) {
-			error = count;
-			goto fail_end_trans;
-		}
-
-		error = gfs2_meta_inode_buffer(ip, &dibh);
-		if (error)
-			goto fail_end_trans;
-
-		if (ip->i_di.di_size < inode->i_size)
-			ip->i_di.di_size = inode->i_size;
-		ip->i_di.di_mtime = ip->i_di.di_ctime = get_seconds();
-
-		gfs2_trans_add_bh(ip->i_gl, dibh, 1);
-		gfs2_dinode_out(&ip->i_di, dibh->b_data);
-		brelse(dibh);
-	}
-
-	gfs2_trans_end(sdp);
-
-	if (file->f_flags & O_SYNC || IS_SYNC(inode)) {
-		gfs2_log_flush_glock(ip->i_gl);
-		error = filemap_fdatawrite(file->f_mapping);
-		if (error == 0)
-			error = filemap_fdatawait(file->f_mapping);
-		if (error)
-			goto fail_ipres;
-	}
-
-	if (alloc_required) {
-		gfs2_assert_warn(sdp, count != size ||
-				 al->al_alloced);
-		gfs2_inplace_release(ip);
-		gfs2_quota_unlock(ip);
-		gfs2_alloc_put(ip);
-	}
-
-	return count;
-
- fail_end_trans:
-	gfs2_trans_end(sdp);
-
- fail_ipres:
-	if (alloc_required)
-		gfs2_inplace_release(ip);
-
- fail_gunlock_q:
-	if (alloc_required)
-		gfs2_quota_unlock(ip);
+	atomic_inc(&get_v2sdp(filp->f_mapping->host->i_sb)->sd_ops_file);
 
- fail:
-	if (alloc_required)
-		gfs2_alloc_put(ip);
-
-	return error;
+	init_sync_kiocb(&kiocb, filp);
+	ret = __gfs2_file_aio_read(&kiocb, iov, nr_segs, ppos);
+	if (-EIOCBQUEUED == ret)
+		ret = wait_on_sync_kiocb(&kiocb);
+	return ret;
 }
 
-/**
- * do_write_buf - Write bytes to a file
- * @file: The file to write to
- * @buf: The buffer to copy from
- * @size: The amount of data requested
- * @offset: The current file offset
- * @num_gh: The number of other locks we need to do the read
- * @gh: the locks we need plus one for our lock
- *
- * Outputs: Offset - updated according to number of bytes written
- *
- * Returns: The number of bytes written, errno on failure
- */
-
-static ssize_t do_write_buf(struct file *file, const char __user *buf, size_t size,
-			    loff_t *offset, unsigned int num_gh,
-			    struct gfs2_holder *ghs)
+static ssize_t gfs2_file_aio_read(struct kiocb *iocb, char __user *buf,
+				  size_t count, loff_t pos)
 {
-	struct gfs2_inode *ip = get_v2ip(file->f_mapping->host);
-	struct gfs2_sbd *sdp = ip->i_sbd;
-	size_t s;
-	ssize_t count = 0;
-	int error;
-
-	gfs2_holder_init(ip->i_gl, LM_ST_EXCLUSIVE, 0, &ghs[num_gh]);
-
-	error = gfs2_glock_nq_m(num_gh + 1, ghs);
-	if (error)
-		goto out;
-
-	if (num_gh) {
-		error = grope_mapping(buf, size);
-		if (error)
-			goto out_gunlock;
-	}
-
-	if (file->f_flags & O_APPEND)
-		*offset = ip->i_di.di_size;
-
-	if (!(file->f_flags & O_LARGEFILE)) {
-		error = -EFBIG;
-		if (*offset >= MAX_NON_LFS)
-			goto out_gunlock;
-		if (*offset + size > MAX_NON_LFS)
-			size = MAX_NON_LFS - *offset;
-	}
-
-	/* split large writes into smaller atomic transactions */
-	while (size) {
-		s = gfs2_tune_get(sdp, gt_max_atomic_write);
-		if (s > size)
-			s = size;
-
-		error = do_do_write_buf(file, buf, s, offset);
-		if (error < 0)
-			goto out_gunlock;
-
-		buf += error;
-		size -= error;
-		count += error;
-	}
-
-	error = 0;
+	struct file *filp = iocb->ki_filp;
+        struct iovec local_iov = { .iov_base = buf, .iov_len = count };
 
- out_gunlock:
-	gfs2_glock_dq_m(num_gh + 1, ghs);
+	atomic_inc(&get_v2sdp(filp->f_mapping->host->i_sb)->sd_ops_file);
 
- out:
-	gfs2_holder_uninit(&ghs[num_gh]);
-
-	return (count) ? count : error;
+        BUG_ON(iocb->ki_pos != pos);
+        return __gfs2_file_aio_read(iocb, &local_iov, 1, &iocb->ki_pos);
 }
 
-/**
- * gfs2_write - Write bytes to a file
- * @file: The file to write to
- * @buf: The buffer to copy from
- * @size: The amount of data requested
- * @offset: The current file offset
- *
- * Outputs: Offset - updated according to number of bytes written
- *
- * Returns: The number of bytes written, errno on failure
- */
-
-static ssize_t gfs2_write(struct file *file, const char __user *buf,
-			  size_t size, loff_t *offset)
-{
-	struct inode *inode = file->f_mapping->host;
-	ssize_t count;
-
-	atomic_inc(&get_v2sdp(inode->i_sb)->sd_ops_file);
-
-	if (*offset < 0)
-		return -EINVAL;
-	if (!access_ok(VERIFY_READ, buf, size))
-		return -EFAULT;
-
-	mutex_lock(&inode->i_mutex);
-	if (file->f_flags & O_DIRECT)
-		count = walk_vm(file, buf, size, offset,
-				do_write_direct);
-	else
-		count = walk_vm(file, buf, size, offset, do_write_buf);
-	mutex_unlock(&inode->i_mutex);
-
-	return count;
-}
 
 /**
  * filldir_reg_func - Report a directory entry to the caller of gfs2_dir_read()
@@ -1158,9 +551,6 @@ static int gfs2_ioctl_flags(struct gfs2_inode *ip, unsigned int cmd, unsigned lo
 		if (flags & (GFS2_DIF_JDATA|GFS2_DIF_DIRECTIO)) {
 			if (!S_ISREG(ip->i_di.di_mode))
 				goto out;
-			/* FIXME: Would be nice not to require the following test */
-			if ((flags & GFS2_DIF_JDATA) && ip->i_di.di_size)
-				goto out;
 		}
 		if (flags & (GFS2_DIF_INHERIT_JDATA|GFS2_DIF_INHERIT_DIRECTIO)) {
 			if (!S_ISDIR(ip->i_di.di_mode))
@@ -1246,21 +636,14 @@ static int gfs2_mmap(struct file *file, struct vm_area_struct *vma)
 		return error;
 	}
 
-	if (gfs2_is_jdata(ip)) {
-		if (vma->vm_flags & VM_MAYSHARE)
-			error = -EOPNOTSUPP;
-		else
-			vma->vm_ops = &gfs2_vm_ops_private;
-	} else {
-		/* This is VM_MAYWRITE instead of VM_WRITE because a call
-		   to mprotect() can turn on VM_WRITE later. */
-
-		if ((vma->vm_flags & (VM_MAYSHARE | VM_MAYWRITE)) ==
-		    (VM_MAYSHARE | VM_MAYWRITE))
-			vma->vm_ops = &gfs2_vm_ops_sharewrite;
-		else
-			vma->vm_ops = &gfs2_vm_ops_private;
-	}
+	/* This is VM_MAYWRITE instead of VM_WRITE because a call
+	   to mprotect() can turn on VM_WRITE later. */
+
+	if ((vma->vm_flags & (VM_MAYSHARE | VM_MAYWRITE)) ==
+	    (VM_MAYSHARE | VM_MAYWRITE))
+		vma->vm_ops = &gfs2_vm_ops_sharewrite;
+	else
+		vma->vm_ops = &gfs2_vm_ops_private;
 
 	gfs2_glock_dq_uninit(&i_gh);
 
@@ -1313,13 +696,6 @@ static int gfs2_open(struct inode *inode, struct file *file)
 		if (ip->i_di.di_flags & GFS2_DIF_DIRECTIO)
 			file->f_flags |= O_DIRECT;
 
-		/* Don't let the user open O_DIRECT on a jdata file */
-
-		if ((file->f_flags & O_DIRECT) && gfs2_is_jdata(ip)) {
-			error = -EINVAL;
-			goto fail_gunlock;
-		}
-
 		gfs2_glock_dq_uninit(&i_gh);
 	}
 
@@ -1446,29 +822,10 @@ static ssize_t gfs2_sendfile(struct file *in_file, loff_t *offset, size_t count,
 			     read_actor_t actor, void *target)
 {
 	struct gfs2_inode *ip = get_v2ip(in_file->f_mapping->host);
-	struct gfs2_holder gh;
-	ssize_t retval;
 
 	atomic_inc(&ip->i_sbd->sd_ops_file);
 
-	gfs2_holder_init(ip->i_gl, LM_ST_SHARED, GL_ATIME, &gh);
-
-	retval = gfs2_glock_nq_atime(&gh);
-	if (retval)
-		goto out;
-
-	if (gfs2_is_jdata(ip))
-		retval = -EOPNOTSUPP;
-	else
-		retval = generic_file_sendfile(in_file, offset, count, actor,
-					       target);
-
-	gfs2_glock_dq(&gh);
-
- out:
-	gfs2_holder_uninit(&gh);
-
-	return retval;
+	return generic_file_sendfile(in_file, offset, count, actor, target);
 }
 
 static int do_flock(struct file *file, int cmd, struct file_lock *fl)
@@ -1567,7 +924,11 @@ static int gfs2_flock(struct file *file, int cmd, struct file_lock *fl)
 struct file_operations gfs2_file_fops = {
 	.llseek = gfs2_llseek,
 	.read = gfs2_read,
-	.write = gfs2_write,
+	.readv = gfs2_file_readv,
+	.aio_read = gfs2_file_aio_read,
+	.write = generic_file_write,
+	.writev = generic_file_writev,
+	.aio_write = generic_file_aio_write,
 	.ioctl = gfs2_ioctl,
 	.mmap = gfs2_mmap,
 	.open = gfs2_open,