[PATCH 3.12 112/122] ocfs2: remove filesize checks for sync I/O journal commit

From: Jiri Slaby
Date: Tue Feb 17 2015 - 07:33:16 EST

From: Goldwyn Rodrigues <rgoldwyn@xxxxxxx>

3.12-stable review patch. If anyone has any objections, please let me know.


commit 86b9c6f3f891019b26f8e5bb11a6faa96bba54a8 upstream.

Filesize is not a good indication that the file needs to be synced.
An example where this breaks is:
1. Open the file in O_SYNC|O_RDWR
2. Read a small portion of the file (say 64 bytes)
3. Lseek to starting of the file
4. Write 64 bytes

If the node crashes, it is not written out to disk because this was not
committed in the journal and the other node which reads the file after
recovery reads stale data (even if the write on the other node was

Signed-off-by: Goldwyn Rodrigues <rgoldwyn@xxxxxxx>
Reviewed-by: Mark Fasheh <mfasheh@xxxxxxx>
Cc: Joel Becker <jlbec@xxxxxxxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
Signed-off-by: Linus Torvalds <torvalds@xxxxxxxxxxxxxxxxxxxx>
Signed-off-by: Jiri Slaby <jslaby@xxxxxxx>
fs/ocfs2/file.c | 4 +---
1 file changed, 1 insertion(+), 3 deletions(-)

diff --git a/fs/ocfs2/file.c b/fs/ocfs2/file.c
index f07941160515..cc6e925749de 100644
--- a/fs/ocfs2/file.c
+++ b/fs/ocfs2/file.c
@@ -2376,9 +2376,7 @@ out_dio:
if (ret < 0)
written = ret;

- if (!ret && ((old_size != i_size_read(inode)) ||
- (old_clusters != OCFS2_I(inode)->ip_clusters) ||
- has_refcount)) {
+ if (!ret) {
ret = jbd2_journal_force_commit(osb->journal->j_journal);
if (ret < 0)
written = ret;

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