On Tue, Feb 04, 2020 at 02:46:16PM +0800, Jason Wang wrote:

On 2020/2/4 下午2:01, Michael S. Tsirkin wrote:

quoted

On Tue, Feb 04, 2020 at 11:30:11AM +0800, Jason Wang wrote:

quoted

5) generate diffs of memory table and using IOMMU API to setup the dma
mapping in this method

Frankly I think that's a bunch of work. Why not a MAP/UNMAP interface?

Sure, so that basically VHOST_IOTLB_UPDATE/INVALIDATE I think?

Do you mean we let userspace to only use VHOST_IOTLB_UPDATE/INVALIDATE
to do the DMA mapping in vhost-vdpa case? When vIOMMU isn't available,
userspace will set msg->iova to GPA, otherwise userspace will set
msg->iova to GIOVA, and vhost-vdpa module will get HPA from msg->uaddr?

Thanks,
Tiwei

Thanks