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>

diff --git a/fs/btrfs/transaction.c b/fs/btrfs/transaction.c
index 8db401fa2f8fb8a2e5b6298c162b72caaabc0a88..e6509b92433b2ac23b7dbbcbfc8c9b54d6107c0f 100644 (file)
--- 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;
 }