code: func (plugin *flexVolumePlugin) GetVolumeName(spec *volume.Spec) (string, error) {
  	call := plugin.NewDriverCall(getVolumeNameCmd)
  	call.AppendSpec(spec, plugin.host, nil)
  
  	_, err := call.Run()
  	if isCmdNotSupportedErr(err) {
  		return (*pluginDefaults)(plugin).GetVolumeName(spec)
  	} else if err != nil {
  		return "", err
  	}
  
  	name, err := (*pluginDefaults)(plugin).GetVolumeName(spec)
  	if err != nil {
  		return "", err
  	}
  
  	klog.Warning(logPrefix(plugin), "GetVolumeName is not supported yet. Defaulting to PV or volume name: ", name)
  
  	return name, nil
  }
docs: // GetVolumeName is part of the volume.VolumePlugin interface.