> Change bus_dmamap_load() to take a proc *, like this:
> 
> 	int bus_dmamap_load __P((bus_dma_tag_t tag, bus_dma_handle_t dmah,
> 		caddr_t va, size_t size, struct proc *p, int flags));

...

> Does this seem like a reasonable way to get this functionality?

OK, this does make sense. A similar modification is needed though for the
bus_dmamap_alloc function to allow allocation of "DMA safe" memory that doesn't
get mapped into kernel virtual address space.

Something like

	caddr_t bus_dmamem_alloc __P((bus_dma_tag tag, size_t size,
		struct proc *p, int nsegments, int flags));

with semantics for proc similar to bus_dmamap_load would probably do.
--
ws@TooLs.DE     (Wolfgang Solfrank, TooLs GmbH) 	+49-228-985800