'Clone backing file for Cinder volume.
:param: is_snapshot Not used, present for method signature consistency'

def _clone_backing_file_for_volume(self, volume_name, clone_name, volume_id, share=None, is_snapshot=False, source_snapshot=None):

    (_host_ip, export_path) = self._get_export_ip_path(volume_id, share)
    storage_path = self.zapi_client.get_actual_path_for_export(export_path)
    target_path = ('%s/%s' % (storage_path, clone_name))
    self.zapi_client.clone_file(('%s/%s' % (storage_path, volume_name)), target_path, source_snapshot)
