def vhost_nvme_controller_add_ns(client, ctrlr, bdev_name):
    """Add namespace to vhost nvme controller.
    Args:
        ctrlr: controller name where to add a namespace
        bdev_name: block device name for a new namespace
    """
    params = {
        'ctrlr': ctrlr,
        'bdev_name': bdev_name,
    }

    return client.call('vhost_nvme_controller_add_ns', params)