1 files changed, 9 insertions, 3 deletions

diff --git a/fs/btrfs/inode.c b/fs/btrfs/inode.c
index 33a9e9da726d..0eab7b67e109 100644
--- a/fs/btrfs/inode.c
+++ b/fs/btrfs/inode.c
@@ -920,7 +920,8 @@ static noinline int __cow_file_range(struct btrfs_trans_handle *trans,
                 }
 
                 em = alloc_extent_map();
-                BUG_ON(!em); /* -ENOMEM */
+                if (!em)
+                        goto out_reserve;
                 em->start = start;
                 em->orig_start = em->start;
                 ram_size = ins.offset;
@@ -947,11 +948,14 @@ static noinline int __cow_file_range(struct btrfs_trans_handle *trans,
                         btrfs_drop_extent_cache(inode, start,
                                                 start + ram_size - 1, 0);
                 }
+                if (ret)
+                        goto out_reserve;
 
                 cur_alloc_size = ins.offset;
                 ret = btrfs_add_ordered_extent(inode, start, ins.objectid,
                                                ram_size, cur_alloc_size, 0);
-                BUG_ON(ret); /* -ENOMEM */
+                if (ret)
+                        goto out_reserve;
 
                 if (root->root_key.objectid ==
                     BTRFS_DATA_RELOC_TREE_OBJECTID) {
@@ -959,7 +963,7 @@ static noinline int __cow_file_range(struct btrfs_trans_handle *trans,
                                                       cur_alloc_size);
                         if (ret) {
                                 btrfs_abort_transaction(trans, root, ret);
-                                goto out_unlock;
+                                goto out_reserve;
                         }
                 }
 
@@ -988,6 +992,8 @@ static noinline int __cow_file_range(struct btrfs_trans_handle *trans,
 out:
         return ret;
 
+out_reserve:
+        btrfs_free_reserved_extent(root, ins.objectid, ins.offset);
 out_unlock:
         extent_clear_unlock_delalloc(inode,
                      &BTRFS_I(inode)->io_tree,