ISP_GET_VPIDX
pt.ctp_vpidx = ISP_GET_VPIDX(isp, chan);
reqp->req_vpidx = ISP_GET_VPIDX(isp, XS_CHANNEL(xs));
tmf->tmf_vpidx = ISP_GET_VPIDX(isp, chan);
ab->abrt_vpidx = ISP_GET_VPIDX(isp, chan);
cto->ct_vpidx = ISP_GET_VPIDX(isp, XS_CHANNEL(ccb));
tmf.tmf_vpidx = ISP_GET_VPIDX(isp, chan);
chan = ISP_GET_VPIDX(isp, inot->in_vpidx);