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>

diff --git a/fs/btrfs/transaction.c b/fs/btrfs/transaction.c
index f154946..fc03aa6 100644 (file)
--- 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,