IFF_DRV_OACTIVE
ifp->if_drv_flags &= ~IFF_DRV_OACTIVE;
ifp->if_drv_flags &= ~(IFF_DRV_RUNNING | IFF_DRV_OACTIVE);
ifp->if_drv_flags |= IFF_DRV_OACTIVE;
(ifp->if_drv_flags & IFF_DRV_OACTIVE) == 0) {
ifp->if_drv_flags |= IFF_DRV_OACTIVE;
if (p && p->ifp->if_drv_flags & IFF_DRV_OACTIVE &&
p->ifp->if_drv_flags &= ~IFF_DRV_OACTIVE;