ext4: 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>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
diff --git a/fs/ext4/super.c b/fs/ext4/super.c
index 8ab0c95..2b13dcf 100644
--- a/fs/ext4/super.c
+++ b/fs/ext4/super.c
@@ -706,6 +706,8 @@
spin_lock_init(&(ei->i_block_reservation_lock));
INIT_LIST_HEAD(&ei->i_aio_dio_complete_list);
ei->cur_aio_dio = NULL;
+ ei->i_sync_tid = 0;
+ ei->i_datasync_tid = 0;
return &ei->vfs_inode;
}