btrfs: flush delayed refs when trying to reserve data space

We can end up with freed extents in the delayed refs, and thus
may_commit_transaction() may not think we have enough pinned space to
commit the transaction and we'll ENOSPC early.  Handle this by running
the delayed refs in order to make sure pinned is uptodate before we try
to commit the transaction.

Tested-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: David Sterba <dsterba@suse.com>

diff --git a/fs/btrfs/space-info.c b/fs/btrfs/space-info.c
index 6d82c444ceff1bc9f6c4d5ec4ceec51a7b085c65..8496518297f3eea0518bc8fb72a82a51ecd99bb6 100644 (file)
--- a/fs/btrfs/space-info.c
+++ b/fs/btrfs/space-info.c
@@ -1023,6 +1023,7 @@ static const enum btrfs_flush_state evict_flush_states[] = {
 static const enum btrfs_flush_state data_flush_states[] = {
        FLUSH_DELALLOC_WAIT,
        RUN_DELAYED_IPUTS,
+       FLUSH_DELAYED_REFS,
        COMMIT_TRANS,
 };