1 files changed, 16 insertions, 0 deletions

diff --git a/fs/btrfs/locking.c b/fs/btrfs/locking.c
index d43e14c7471a..0cc314c10d66 100644
--- a/fs/btrfs/locking.c
+++ b/fs/btrfs/locking.c
@@ -56,3 +56,19 @@ int btrfs_tree_locked(struct extent_buffer *eb)
 {
         return mutex_is_locked(&eb->mutex);
 }
+
+int btrfs_path_lock_waiting(struct btrfs_path *path, int level)
+{
+        int i;
+        struct extent_buffer *eb;
+        for (i = level; i <= level + 1 && i < BTRFS_MAX_LEVEL; i++) {
+                eb = path->nodes[i];
+                if (!eb)
+                        break;
+                smp_mb();
+                if (!list_empty(&eb->mutex.wait_list))
+                        return 1;
+        }
+        return 0;
+}
+