Re: (reposting) how to get DMA'able memory within 4GB on 64-bit m achi ne

David S. Miller
2001-06-29T09:50:42Z

Jes Sorensen writes:
> Thats easy
...
> This way you automatically get support for the situation Ben mentioned
> as well, when doing large allocs and the IOMMU is full you return a
> full 64 bit address.

And when the IOMMU is "full" what happens to all the SAC only
cards in the machine? pci_map_{single,sg}() are not allowed
to fail.

See, it's not so easy.

Later,
David S. Miller
davem@redhat.com