'Get volume status.
If refresh is True, update the status first.'

def get_volume_stats(self, refresh=False):

    if ((self._volume_stats is None) or refresh):
        self._update_volume_stats()
    LOG.info('Successfully    update    volume    stats.    backend:    %(volume_backend_name)s,    vendor:    %(vendor_name)s,    driver    version:    %(driver_version)s,    storage    protocol:    %(storage_protocol)s.', self._volume_stats)
    return self._volume_stats
