code: func (attacher *rbdAttacher) GetDeviceMountPath(spec *volume.Spec) (string, error) {
  	img, err := getVolumeSourceImage(spec)
  	if err != nil {
  		return "", err
  	}
  	pool, err := getVolumeSourcePool(spec)
  	if err != nil {
  		return "", err
  	}
  	return makePDNameInternal(attacher.plugin.host, pool, img), nil
  }
docs: // GetDeviceMountPath implements Attacher.GetDeviceMountPath.