Btrfs: don't start a new transaction when starting sync
If there is no running transaction in the fs, we needn't start a new one when
we want to start sync.
Signed-off-by: Miao Xie <miaox@cn.fujitsu.com>
Signed-off-by: Chris Mason <chris.mason@fusionio.com>
diff --git a/fs/btrfs/ioctl.c b/fs/btrfs/ioctl.c
index 5022e62..7b1f614 100644
--- a/fs/btrfs/ioctl.c
+++ b/fs/btrfs/ioctl.c
@@ -3065,16 +3065,22 @@
u64 transid;
int ret;
- trans = btrfs_start_transaction(root, 0);
- if (IS_ERR(trans))
- return PTR_ERR(trans);
+ trans = btrfs_attach_transaction(root);
+ if (IS_ERR(trans)) {
+ if (PTR_ERR(trans) != -ENOENT)
+ return PTR_ERR(trans);
+
+ /* No running transaction, don't bother */
+ transid = root->fs_info->last_trans_committed;
+ goto out;
+ }
transid = trans->transid;
ret = btrfs_commit_transaction_async(trans, root, 0);
if (ret) {
btrfs_end_transaction(trans, root);
return ret;
}
-
+out:
if (argp)
if (copy_to_user(argp, &transid, sizeof(transid)))
return -EFAULT;
