Btrfs: fix missing release of the space/qgroup reservation in start_transaction()

When we fail to start a transaction, we need to release the reserved free space
and qgroup space, fix it.

Signed-off-by: Miao Xie <miaox@cn.fujitsu.com>
Reviewed-by: Jan Schmidt <list.btrfs@jan-o-sch.net>
Signed-off-by: Josef Bacik <jbacik@fusionio.com>

1 files changed, 19 insertions, 8 deletions

diff --git a/fs/btrfs/transaction.c b/fs/btrfs/transaction.c
index f15494699f3b..fc03aa60b684 100644
--- a/fs/btrfs/transaction.c
+++ b/fs/btrfs/transaction.c
@@ -333,12 +333,14 @@ start_transaction(struct btrfs_root *root, u64 num_items, int type,
                                           &root->fs_info->trans_block_rsv,
                                           num_bytes, flush);
                 if (ret)
-                        return ERR_PTR(ret);
+                        goto reserve_fail;
         }
 again:
         h = kmem_cache_alloc(btrfs_trans_handle_cachep, GFP_NOFS);
-        if (!h)
-                return ERR_PTR(-ENOMEM);
+        if (!h) {
+                ret = -ENOMEM;
+                goto alloc_fail;
+        }
 
         /*
          * If we are JOIN_NOLOCK we're already committing a transaction and
@@ -365,11 +367,7 @@ again:
         if (ret < 0) {
                 /* We must get the transaction if we are JOIN_NOLOCK. */
                 BUG_ON(type == TRANS_JOIN_NOLOCK);
-
-                if (type < TRANS_JOIN_NOLOCK)
-                        sb_end_intwrite(root->fs_info->sb);
-                kmem_cache_free(btrfs_trans_handle_cachep, h);
-                return ERR_PTR(ret);
+                goto join_fail;
         }
 
         cur_trans = root->fs_info->running_transaction;
@@ -410,6 +408,19 @@ got_it:
         if (!current->journal_info && type != TRANS_USERSPACE)
                 current->journal_info = h;
         return h;
+
+join_fail:
+        if (type < TRANS_JOIN_NOLOCK)
+                sb_end_intwrite(root->fs_info->sb);
+        kmem_cache_free(btrfs_trans_handle_cachep, h);
+alloc_fail:
+        if (num_bytes)
+                btrfs_block_rsv_release(root, &root->fs_info->trans_block_rsv,
+                                        num_bytes);
+reserve_fail:
+        if (qgroup_reserved)
+                btrfs_qgroup_free(root, qgroup_reserved);
+        return ERR_PTR(ret);
 }
 
 struct btrfs_trans_handle *btrfs_start_transaction(struct btrfs_root *root,