Btrfs: fix sync subvol/snapshot creation

We were incorrectly taking the async path even for the sync ioctls by
passing in &transid unconditionally.

There's ample room for further cleanup here, but this keeps the fix simple.

Signed-off-by: Sage Weil <sage@newdream.net>
Reviewed-by: Li Zefan <lizf@cn.fujitsu.com>
Signed-off-by: Chris Mason <chris.mason@oracle.com>

diff --git a/fs/btrfs/ioctl.c b/fs/btrfs/ioctl.c
index f1c9bb4..7cc2e8e 100644 (file)
--- a/fs/btrfs/ioctl.c
+++ b/fs/btrfs/ioctl.c
@@ -964,6 +964,15 @@ static noinline int btrfs_ioctl_snap_create(struct file *file,
                name = async_vol_args->name;
                fd = async_vol_args->fd;
                async_vol_args->name[BTRFS_SNAPSHOT_NAME_MAX] = '\0';
+
+               ret = btrfs_ioctl_snap_create_transid(file, name, fd,
+                                                     subvol, &transid);
+
+               if (ret == 0 &&
+                   copy_to_user(arg +
+                                offsetof(struct btrfs_ioctl_async_vol_args,
+                                         transid), &transid, sizeof(transid)))
+                       ret = -EFAULT;
        } else {
                vol_args = memdup_user(arg, sizeof(*vol_args));
                if (IS_ERR(vol_args))
@@ -971,16 +980,9 @@ static noinline int btrfs_ioctl_snap_create(struct file *file,
                name = vol_args->name;
                fd = vol_args->fd;
                vol_args->name[BTRFS_PATH_NAME_MAX] = '\0';
-       }
 
-       ret = btrfs_ioctl_snap_create_transid(file, name, fd,
-                                             subvol, &transid);
-
-       if (!ret && async) {
-               if (copy_to_user(arg +
-                               offsetof(struct btrfs_ioctl_async_vol_args,
-                               transid), &transid, sizeof(transid)))
-                       return -EFAULT;
+               ret = btrfs_ioctl_snap_create_transid(file, name, fd,
+                                                     subvol, NULL);
        }
 
        kfree(vol_args);