ext3: Wait for proper transaction commit on fsync

We cannot rely on buffer dirty bits during fsync because pdflush can come
before fsync is called and clear dirty bits without forcing a transaction
commit. What we do is that we track which transaction has last changed
the inode and which transaction last changed allocation and force it to
disk on fsync.

Signed-off-by: Jan Kara <jack@suse.cz>
Reviewed-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>

1 files changed, 8 insertions, 0 deletions

diff --git a/include/linux/ext3_fs_i.h b/include/linux/ext3_fs_i.h
index ca1bfe90004f..93e7428156ba 100644
--- a/include/linux/ext3_fs_i.h
+++ b/include/linux/ext3_fs_i.h
@@ -137,6 +137,14 @@ struct ext3_inode_info {
          * by other means, so we have truncate_mutex.
          */
         struct mutex truncate_mutex;
+
+        /*
+         * Transactions that contain inode's metadata needed to complete
+         * fsync and fdatasync, respectively.
+         */
+        atomic_t i_sync_tid;
+        atomic_t i_datasync_tid;
+
         struct inode vfs_inode;
 };