Btrfs: make flushoncommit mount option correctly wait on ordered_extents

The commit_transaction call to wait_ordered_extents when snap_pending
passes nocow_only=1 to process only NOCOW or PREALLOC extents.  This isn't
correct for the 'flushoncommit' mode, as it skips extents we just started
IO on in start_delalloc_inodes.

So, in the flushoncommit case, wait on all ordered extents.  Otherwise,
only pass the nocow_only flag to wait_ordered_extents if snap_pending.

Signed-off-by: Sage Weil <sage@newdream.net>
Signed-off-by: Chris Mason <chris.mason@oracle.com>

diff --git a/fs/btrfs/transaction.c b/fs/btrfs/transaction.c
index 32454d1..e51d2bc 100644 (file)
--- a/fs/btrfs/transaction.c
+++ b/fs/btrfs/transaction.c
@@ -942,9 +942,11 @@ int btrfs_commit_transaction(struct btrfs_trans_handle *trans,
 
                mutex_unlock(&root->fs_info->trans_mutex);
 
-               if (flush_on_commit || snap_pending) {
-                       if (flush_on_commit)
-                               btrfs_start_delalloc_inodes(root);
+               if (flush_on_commit) {
+                       btrfs_start_delalloc_inodes(root);
+                       ret = btrfs_wait_ordered_extents(root, 0);
+                       BUG_ON(ret);
+               } else if (snap_pending) {
                        ret = btrfs_wait_ordered_extents(root, 1);
                        BUG_ON(ret);
                }