Re: Proposal: Eliminate GFP_DMA

[Jeff Garzik <jgarzik@pobox.com>]

On Fri, Feb 28, 2003 at 03:56:15PM +0100, Andi Kleen wrote:
> On Fri, Feb 28, 2003 at 03:55:37PM +0000, Alan Cox wrote:
> > On Fri, 2003-02-28 at 14:34, Matthew Wilcox wrote:
> > > umm.  are you volunteering to convert drivers/net/macmace.c to the pci_*
> > > API then?  also, GFP_DMA is used on, eg, s390 to get memory below 2GB and
> > > on ia64 to get memory below 4GB.
> > 
> > The ia64 is a fine example of how broken it is. People have to hack around 
> > with GFP_DMA meaning different things on ia64 to everything else. It needs
> > to die. 
> 
> At least on x86-64 it is still needed when you need have some hardware
> with address limits < 4GB (e.g. an 24bit soundcard)
> 
> pci_* on K8 only allows address mask 0xffffffff or unlimited.

That's a bit broken...  I have an ALS4000 PCI soundcard that is a 24-bit
soundcard.  pci_set_dma_mask should support 24-bits accordingly,
otherwise it's a bug in your platform implementation...  Nobody will be
able to use certain properly-written drivers on your platform otherwise.

	Jeff