Btrfs: fix wrong reserved space in qgroup during snap/subv creation

There are two problems in the space reservation of the snapshot/
subvolume creation.
- don't reserve the space for the root item insertion
- the space which is reserved in the qgroup is different with
  the free space reservation. we need reserve free space for
  7 items, but in qgroup reservation, we need reserve space only
  for 3 items.

So we implement new metadata reservation functions for the
snapshot/subvolume creation.

Signed-off-by: Miao Xie <miaox@cn.fujitsu.com>
Signed-off-by: Josef Bacik <jbacik@fusionio.com>

1 files changed, 1 insertions, 3 deletions

diff --git a/fs/btrfs/transaction.c b/fs/btrfs/transaction.c
index 71de435a291e..f11c2e0a3746 100644
--- a/fs/btrfs/transaction.c
+++ b/fs/btrfs/transaction.c
@@ -1082,7 +1082,7 @@ static noinline int create_pending_snapshot(struct btrfs_trans_handle *trans,
         path = btrfs_alloc_path();
         if (!path) {
                 ret = pending->error = -ENOMEM;
-                goto path_alloc_fail;
+                return ret;
         }
 
         new_root_item = kmalloc(sizeof(*new_root_item), GFP_NOFS);
@@ -1279,8 +1279,6 @@ no_free_objectid:
         kfree(new_root_item);
 root_item_alloc_fail:
         btrfs_free_path(path);
-path_alloc_fail:
-        btrfs_block_rsv_release(root, &pending->block_rsv, (u64)-1);
         return ret;
 }