Btrfs: fix wrong return value of btrfs_wait_for_commit()

If the id of the existed transaction is more than the one we specified, it
means the specified transaction was commited, so we should return 0, not
EINVAL.

Signed-off-by: Miao Xie <miaox@cn.fujitsu.com>
Signed-off-by: Chris Mason <chris.mason@fusionio.com>

1 files changed, 8 insertions, 7 deletions

diff --git a/fs/btrfs/transaction.c b/fs/btrfs/transaction.c
index 8db401fa2f8f..e6509b92433b 100644
--- a/fs/btrfs/transaction.c
+++ b/fs/btrfs/transaction.c
@@ -456,28 +456,31 @@ static noinline void wait_for_commit(struct btrfs_root *root,
 int btrfs_wait_for_commit(struct btrfs_root *root, u64 transid)
 {
         struct btrfs_transaction *cur_trans = NULL, *t;
-        int ret;
+        int ret = 0;
 
-        ret = 0;
         if (transid) {
                 if (transid <= root->fs_info->last_trans_committed)
                         goto out;
 
+                ret = -EINVAL;
                 /* find specified transaction */
                 spin_lock(&root->fs_info->trans_lock);
                 list_for_each_entry(t, &root->fs_info->trans_list, list) {
                         if (t->transid == transid) {
                                 cur_trans = t;
                                 atomic_inc(&cur_trans->use_count);
+                                ret = 0;
                                 break;
                         }
-                        if (t->transid > transid)
+                        if (t->transid > transid) {
+                                ret = 0;
                                 break;
+                        }
                 }
                 spin_unlock(&root->fs_info->trans_lock);
-                ret = -EINVAL;
+                /* The specified transaction doesn't exist */
                 if (!cur_trans)
-                        goto out;  /* bad transid */
+                        goto out;
         } else {
                 /* find newest transaction that is committing | committed */
                 spin_lock(&root->fs_info->trans_lock);
@@ -497,9 +500,7 @@ int btrfs_wait_for_commit(struct btrfs_root *root, u64 transid)
         }
 
         wait_for_commit(root, cur_trans);
-
         put_transaction(cur_trans);
-        ret = 0;
 out:
         return ret;
 }