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

Blue Swirl
2008-12-12T19:09:24Z

On 12/12/08, Andrea Arcangeli <aarcange@redhat.com> wrote:
> From: Andrea Arcangeli <aarcange@redhat.com>
>
> Add can_dma and post_dma methods needed before/after direct IO to guest
> physical memory.
>
> Signed-off-by: Andrea Arcangeli <aarcange@redhat.com>

> + /* nonlinear range */
> + if (pd_first != pd)
> + return NULL;

In my tests on Sparc32, IOMMU can map a linear DVMA range to several
non-linear physical pages, so this case should be handled correctly.