Btrfs: clean up search_extent_mapping()

rb_node returned by __tree_search() can be a valid pointer or NULL,
but won't be some errno.

Signed-off-by: Li Zefan <lizf@cn.fujitsu.com>
Signed-off-by: Chris Mason <chris.mason@oracle.com>

1 files changed, 3 insertions, 14 deletions

diff --git a/fs/btrfs/extent_map.c b/fs/btrfs/extent_map.c
index 2d0410344ea3..911a9db801e0 100644
--- a/fs/btrfs/extent_map.c
+++ b/fs/btrfs/extent_map.c
@@ -379,23 +379,12 @@ struct extent_map *search_extent_mapping(struct extent_map_tree *tree,
                 em = rb_entry(next, struct extent_map, rb_node);
                 goto found;
         }
-        if (!rb_node) {
-                em = NULL;
-                goto out;
-        }
-        if (IS_ERR(rb_node)) {
-                em = ERR_CAST(rb_node);
-                goto out;
-        }
-        em = rb_entry(rb_node, struct extent_map, rb_node);
-        goto found;
-
-        em = NULL;
-        goto out;
+        if (!rb_node)
+                return NULL;
 
+        em = rb_entry(rb_node, struct extent_map, rb_node);
 found:
         atomic_inc(&em->refs);
-out:
         return em;
 }