Re: [Qemu-devel] Re: [PATCH 2 of 5] add can_dma/post_dma for direct IO

Blue Swirl
2008-12-16T16:35:10Z

On 12/16/08, Paul Brook <paul@codesourcery.com> wrote:
> > The generic resolving API should look something like
> >
> > int (*resolve)(target_phys_addr_t address_in, target_phys_addr_t
> > length_in, target_phys_addr_t &address_out, target_phys_addr_t
> > &length_out)
>
>
> I don't think this is sufficient. A paged iommu may split a single range into
> multiple disjoint sections. i.e. we need SG lists.

That's why there is the length_out, it is called repeatedly until the
length is zero or it fails.