'Get volume stats. This is more of getting group stats.'

def get_volume_stats(self, refresh=False):

    LOG.debug('in    get_volume_stats')
    if refresh:
        backend_name = (self.configuration.safe_get('volume_backend_name') or self.__class__.__name__)
        LOG.debug('backend_name=%(backend_name)s', {'backend_name': backend_name})
        selected_pool = self.api_executor.get_specific_poolinfo(self.configuration.qnap_poolname)
        capacity_bytes = int(selected_pool.find('capacity_bytes').text)
        LOG.debug('capacity_bytes:    %s    GB', (capacity_bytes / units.Gi))
        freesize_bytes = int(selected_pool.find('freesize_bytes').text)
        LOG.debug('freesize_bytes:    %s    GB', (freesize_bytes / units.Gi))
        provisioned_bytes = int(selected_pool.find('allocated_bytes').text)
        driver_protocol = self.configuration.qnap_storage_protocol
        LOG.debug('provisioned_bytes:    %s    GB', (provisioned_bytes / units.Gi))
        self.group_stats = {'volume_backend_name': backend_name, 'vendor_name': 'QNAP', 'driver_version': self.VERSION, 'storage_protocol': driver_protocol}
        single_pool = dict(pool_name=self.configuration.qnap_poolname, total_capacity_gb=(capacity_bytes / units.Gi), free_capacity_gb=(freesize_bytes / units.Gi), provisioned_capacity_gb=(provisioned_bytes / units.Gi), reserved_percentage=self.configuration.reserved_percentage, QoS_support=False)
        self.group_stats['pools'] = [single_pool]
        return self.group_stats
