[PATCH] xen/arm64: do not call the swiotlb functions twice

[Ian Campbell]

On Mon, 2013-12-09 at 16:06 +0000, Stefano Stabellini wrote:
> On arm64 the dma_map_ops implementation is based on the swiotlb.
> swiotlb-xen, used by default in dom0 on Xen, is also based on the
> swiotlb.
> 
> Avoid calling into the default arm64 dma_map_ops functions from
> xen_dma_map_page, xen_dma_unmap_page, xen_dma_sync_single_for_cpu, and
> xen_dma_sync_single_for_device otherwise we end up calling into the
> swiotlb twice.
> 
> When arm64 gets a non-swiotlb based implementation of dma_map_ops, we'll
> probably have to reintroduce dma_map_ops calls in page-coherent.h.
> 
> Signed-off-by: Stefano Stabellini <stefano.stabellini at eu.citrix.com>
> CC: catalin.marinas at arm.com
> CC: Will.Deacon at arm.com

Tested-by: Ian Campbell <ian.campbell at citrix.com>

Ian.