Btrfs: catch errors from btrfs_sync_log

btrfs_sync_log returns -EAGAIN when we need full transaction commits
instead of small log commits, but sometimes we were dropping the return
value.

In practice, we check for this a few different ways, but this is still a
bug that can leave off full log commits when we really need them.

Signed-off-by: Chris Mason <chris.mason@oracle.com>

1 files changed, 2 insertions, 1 deletions

diff --git a/fs/btrfs/tree-log.c b/fs/btrfs/tree-log.c
index c25a41d86118..42dfc3077040 100644
--- a/fs/btrfs/tree-log.c
+++ b/fs/btrfs/tree-log.c
@@ -2051,6 +2051,7 @@ int btrfs_sync_log(struct btrfs_trans_handle *trans,
                 wait_log_commit(trans, log_root_tree,
                                 log_root_tree->log_transid);
                 mutex_unlock(&log_root_tree->log_mutex);
+                ret = 0;
                 goto out;
         }
         atomic_set(&log_root_tree->log_commit[index2], 1);
@@ -2115,7 +2116,7 @@ out:
         smp_mb();
         if (waitqueue_active(&root->log_commit_wait[index1]))
                 wake_up(&root->log_commit_wait[index1]);
-        return 0;
+        return ret;
 }
 
 static void free_log_tree(struct btrfs_trans_handle *trans,