timeout()/untimeout() API:
- Clients supply callout handle storage, thus eliminating problems of
resource allocation.
- Insertion and removal of callouts is constant time, important as
this facility is used quite a lot in the kernel.
The old timeout()/untimeout() API has been removed from the kernel.
to a softc, rather than a unit number. Add a "dq_softc" member
to struct devqueue; this is a temporary measure until the
dma/controller/device callback spaghetti is untangled.
YAY! No more need for dcafastservice!
HIL: squish instances of "(void) splhil()" and "(void) spl0();".