[rfc] Radeon AGP support patches

[Konstantin Belousov]

On Mon, Oct 27, 2014 at 05:00:55PM +0100, Tijl Coosemans wrote:
> In ttm_agp_bind the ttm->pages array is already populated.  These are
> the pages that need to be put into the GTT.  The patch modifies struct
> agp_memory in sys/dev/agp such that ttm->pages can be passed via
> agp_bind_memory.  Maybe it would be better to add two new functions to
> sys/dev/agp/agp.c: agp_bind_pages and agp_unbind_pages.  These would
> take a vm_page_t array as argument and bind/unbind the pages directly
> in the GTT.  There's no need for ttm_agp_bind to call agp_alloc_memory
> then and struct agp_memory would not be involved at all.  Does that
> sound better?

Yes, this approach is much better IMO.  Having discriminated storage
for the bound pages is too ugly; was the whole code audited for correctness
after the change ?