void nbd_export_close(NBDExport *exp)
{
    NBDClient *client, *next;

    nbd_export_get(exp);
    QTAILQ_FOREACH_SAFE(client, &exp->clients, next, next) {
        client_close(client, true);
    }
    nbd_export_set_name(exp, NULL);
    nbd_export_set_description(exp, NULL);
    nbd_export_put(exp);
}
void nbd_export_close(NBDExport *exp)
{
    NBDClient *client, *next;

    nbd_export_get(exp);
    QTAILQ_FOREACH_SAFE(client, &exp->clients, next, next) {
        client_close(client, true);
    }
    nbd_export_set_name(exp, NULL);
    nbd_export_set_description(exp, NULL);
    nbd_export_put(exp);
}