'Broadcast upwards that a block device mapping was destroyed.
One of device_name or volume_id should be specified.'

def bdm_destroy_at_top(self, ctxt, instance_uuid, device_name=None, volume_id=None):

    cctxt = self.client.prepare(version='1.10')
    try:
        cctxt.cast(ctxt, 'bdm_destroy_at_top', instance_uuid=instance_uuid, device_name=device_name, volume_id=volume_id)
    except Exception:
        LOG.exception('Failed    to    notify    cells    of    BDM    destroy.')
