def METHOD_NAME(self, mnt):
    current_label = self.current_label(mnt)
    if current_label is not None:
        label = current_label
        raw_btrfs_label = current_label.replace(self.svc.name, "{name}")
    else:
        label = self.btrfs_label
        raw_btrfs_label = self.raw_btrfs_label
    self.svc.set_multi(["%s.dev=%s" % (self.rid, "LABEL="+raw_btrfs_label)])
    self.unset_lazy("device")
    self.wait_label(label)