Btrfs: remove the code for the impossible case in cleanup_transaction()

If the transaction is removed from the transaction list, it means the
transaction has been committed successfully. So it is impossible to
call cleanup_transaction(), otherwise there is something wrong with
the code logic. Thus, we use BUG_ON() instead of the original handle.

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

1 files changed, 6 insertions, 5 deletions

diff --git a/fs/btrfs/transaction.c b/fs/btrfs/transaction.c
index bc22be9b69b4..cf8706ce85ac 100644
--- a/fs/btrfs/transaction.c
+++ b/fs/btrfs/transaction.c
@@ -1450,11 +1450,12 @@ static void cleanup_transaction(struct btrfs_trans_handle *trans,
 
         spin_lock(&root->fs_info->trans_lock);
 
-        if (list_empty(&cur_trans->list)) {
-                spin_unlock(&root->fs_info->trans_lock);
-                btrfs_end_transaction(trans, root);
-                return;
-        }
+        /*
+         * If the transaction is removed from the list, it means this
+         * transaction has been committed successfully, so it is impossible
+         * to call the cleanup function.
+         */
+        BUG_ON(list_empty(&cur_trans->list));
 
         list_del_init(&cur_trans->list);
         if (cur_trans == root->fs_info->running_transaction) {