ipvlan_addr_busy
bool ipvlan_addr_busy(struct ipvl_port *port, void *iaddr, bool is_v6);
if (ipvlan_addr_busy(ipvlan->port, &ivi->ivi_addr, false)) {
if (ipvlan_addr_busy(ipvlan->port, ip6_addr, true))
if (ipvlan_addr_busy(ipvlan->port, &i6vi->i6vi_addr, true)) {
if (ipvlan_addr_busy(ipvlan->port, ip4_addr, false))