DRIVER_DMAOK
if (reqp->dr_flag & DRIVER_DMAOK) {
reqp->dr_flag &= ~DRIVER_DMAOK;
reqp->dr_flag |= DRIVER_DMAOK;
tmp->dr_flag = (reqp->dr_flag & ~DRIVER_DMAOK) |
if (reqp->dr_flag & DRIVER_DMAOK) {
reqp->dr_flag &= ~DRIVER_DMAOK;
reqp->dr_flag |= DRIVER_DMAOK;
(reqp->dr_flag & ~DRIVER_DMAOK) | DRIVER_LINKCHK;