static void dn_dev_sysctl_unregister(struct dn_dev_parms *parms)
{
	if (parms->sysctl) {
		struct dn_dev_sysctl_table *t = parms->sysctl;
		parms->sysctl = NULL;
		unregister_net_sysctl_table(t->sysctl_header);
		kfree(t);
	}
}
static void dn_dev_sysctl_unregister(struct dn_dev_parms *parms)
{
	if (parms->sysctl) {
		struct dn_dev_sysctl_table *t = parms->sysctl;
		parms->sysctl = NULL;
		unregister_net_sysctl_table(t->sysctl_header);
		kfree(t);
	}
}