Re: PCI domain stuff

[H. Peter Anvin]

Andy Isaacson wrote:
> On Mon, Jun 30, 2003 at 11:03:29PM -0700, David S. Miller wrote:
> 
>>   From: "H. Peter Anvin" <[e-mail]>
>>   Date: Mon, 30 Jun 2003 23:06:52 -0700
>>
>>   Perhaps a libdirectio would be useful?
>>   
>>The details are very PCI specific, so what you'd be working
>>on initially is a PCI centric library.
>>
>>Over time things can be abstracted, but the initial PCI specific
>>one would be good enough for xfree86 to link to and make use
>>of which is a huge step in the right direction.
> 
> 
> There is some interest in the NetBSD project for such an API, as well.
> <fair at netbsd.org> filed xsrc/21986 last week.
> http://www.netbsd.org/cgi-bin/query-pr-single.pl?number=21986
> 
> Perhaps a common implementation could develop.
> 
> (OK, I can dream...)
> 

Right, and the article brings up a particularly nasty issue -- PCI 
probing from userspace is dangerous as it's inherently not atomic.  That 
really *is* the kernel's job, and abstracting that via a library would 
make it a lot less obnoxious from XFree86's standpoint.

	-hpa