fillw_io
fillw_io(attr | c, vtb->vtb_buffer, vtb->vtb_size);
fillw_io(attr | c, vtb->vtb_buffer + at, count);
fillw_io(attr | c, vtb->vtb_buffer + at + len,
fillw_io(attr | c, vtb->vtb_buffer + at, count);
fillw_io(val, adp->va_window, l/sizeof(u_int16_t));