code: func isDirMounted(plug *csiPlugin, dir string) (bool, error) {
  	mounter := plug.host.GetMounter(plug.GetPluginName())
  	notMnt, err := mounter.IsLikelyNotMountPoint(dir)
  	if err != nil && !os.IsNotExist(err) {
  		klog.Error(log("isDirMounted IsLikelyNotMountPoint test failed for dir [%v]", dir))
  		return false, err
  	}
  	return !notMnt, nil
  }
docs: // isDirMounted returns the !notMounted result from IsLikelyNotMountPoint check