1 files changed, 13 insertions, 4 deletions

diff --git a/fs/btrfs/extent-tree.c b/fs/btrfs/extent-tree.c
index 3e2f969de42d..9ab099bc01a4 100644
--- a/fs/btrfs/extent-tree.c
+++ b/fs/btrfs/extent-tree.c
@@ -1091,16 +1091,26 @@ out:
 int btrfs_cache_ref(struct btrfs_trans_handle *trans, struct btrfs_root *root,
                     struct extent_buffer *buf, u32 nr_extents)
 {
-        u32 nritems;
         struct btrfs_key key;
         struct btrfs_file_extent_item *fi;
+        u64 root_gen;
+        u32 nritems;
         int i;
         int level;
         int ret = 0;
+        int shared = 0;
 
         if (!root->ref_cows)
                 return 0;
 
+        if (root->root_key.objectid != BTRFS_TREE_RELOC_OBJECTID) {
+                shared = 0;
+                root_gen = root->root_key.offset;
+        } else {
+                shared = 1;
+                root_gen = trans->transid - 1;
+        }
+
         level = btrfs_header_level(buf);
         nritems = btrfs_header_nritems(buf);
 
@@ -1114,7 +1124,7 @@ int btrfs_cache_ref(struct btrfs_trans_handle *trans, struct btrfs_root *root,
                         goto out;
                 }
 
-                ref->root_gen = root->root_key.offset;
+                ref->root_gen = root_gen;
                 ref->bytenr = buf->start;
                 ref->owner = btrfs_header_owner(buf);
                 ref->generation = btrfs_header_generation(buf);
@@ -1143,8 +1153,7 @@ int btrfs_cache_ref(struct btrfs_trans_handle *trans, struct btrfs_root *root,
                         info++;
                 }
 
-                BUG_ON(!root->ref_tree);
-                ret = btrfs_add_leaf_ref(root, ref);
+                ret = btrfs_add_leaf_ref(root, ref, shared);
                 WARN_ON(ret);
                 btrfs_free_leaf_ref(root, ref);
         }