func (f *stubBlockVolume) TearDownDevice(mapPath string, devicePath string) error {
	return nil
}

func (f *stubBlockVolume) UnmapPodDevice() error {
	return nil
}

func (f *stubBlockVolume) SupportsMetrics() bool {
	return false
}

func (f *stubBlockVolume) GetMetrics() (*volume.Metrics, error) {
	return nil, nil

* Flex drivers by default do not produce metrics. Flex plugins can enable metrics collection by setting  the capability 'supportsMetrics' to true. Make sure the file system can support fs stat to produce metrics in this case. ([#67508](https://github.com/kubernetes/kubernetes/pull/67508), [@brahmaroutu](https://github.com/brahmaroutu))