[PATCH] ext4: Make non-journal fsync work properly. (Version 3)

[Frank Mayhar <fmayhar@google.com>]

This patch follows Aneesh' suggestion of just calling
sync_dirty_buffer() directly.  Sorry about the delay, I've been busy

Teach ext4_write_inode() about non-journal mode in a better way,
suggested upstream.  Instead of using ext4_do_update_inode(), it
now calls sync_dirty_buffer() directly.  Also handle possible
error return from that function.

Signed-off-by: Frank Mayhar <fmayhar@google.com>

 fs/ext4/inode.c |   37 +++++++++++++++++++++++++++++--------
 1 files changed, 29 insertions(+), 8 deletions(-)

diff --git a/fs/ext4/inode.c b/fs/ext4/inode.c
index d87f6a0..ab31cc4 100644
--- a/fs/ext4/inode.c
+++ b/fs/ext4/inode.c
@@ -4892,19 +4892,40 @@ out_brelse:
  */
 int ext4_write_inode(struct inode *inode, int wait)
 {
+	int err;
+
 	if (current->flags & PF_MEMALLOC)
 		return 0;
 
-	if (ext4_journal_current_handle()) {
-		jbd_debug(1, "called recursively, non-PF_MEMALLOC!\n");
-		dump_stack();
-		return -EIO;
-	}
+	if (EXT4_SB(inode->i_sb)->s_journal) {
+		if (ext4_journal_current_handle()) {
+			jbd_debug(1, "called recursively, non-PF_MEMALLOC!\n");
+			dump_stack();
+			return -EIO;
+		}
 
-	if (!wait)
-		return 0;
+		if (!wait)
+			return 0;
+
+		err = ext4_force_commit(inode->i_sb);
+	} else {
+		struct ext4_iloc iloc;
 
-	return ext4_force_commit(inode->i_sb);
+		err = ext4_get_inode_loc(inode, &iloc);
+		if (err)
+			return err;
+		if (wait)
+			sync_dirty_buffer(iloc.bh);
+		if (buffer_req(iloc.bh) && !buffer_uptodate(iloc.bh)) {
+			ext4_error(inode->i_sb, __func__,
+				   "IO error syncing inode, "
+				   "inode=%lu, block=%llu",
+				   inode->i_ino,
+				   (unsigned long long)iloc.bh->b_blocknr);
+			err = -EIO;
+		}
+	}
+	return err;
 }
 
 /*

-- 
Frank Mayhar <fmayhar@google.com>
Google, Inc.