Virtualization - Jul 2023 - [PATCH vhost v11 05/10] virtio_ring: introduce virtqueue_dma_dev()

On Mon, 24 Jul 2023 09:43:42 -0700, Christoph Hellwig <hch at
infradead.org> wrote:
> On Thu, Jul 20, 2023 at 01:21:07PM -0400, Michael S. Tsirkin wrote:
> > Well I think we can add wrappers like virtio_dma_sync and so on.
> > There are NOP for non-dma so passing the dma device is harmless.
>
> Yes, please.

I am not sure I got this fully.

Are you mean this:
https://lore.kernel.org/all/20230214072704.126660-8-xuanzhuo at
linux.alibaba.com/
https://lore.kernel.org/all/20230214072704.126660-9-xuanzhuo at
linux.alibaba.com/

Then the driver must do dma operation(map and sync) by these virtio_dma_* APIs.
No care the device is non-dma device or dma device.

Then the AF_XDP must use these virtio_dma_* APIs for virtio device.

Thanks

On Tue, Jul 25, 2023 at 10:13:48AM +0800, Xuan Zhuo
wrote:
> On Mon, 24 Jul 2023 09:43:42 -0700, Christoph Hellwig <hch at
infradead.org> wrote:
> > On Thu, Jul 20, 2023 at 01:21:07PM -0400, Michael S. Tsirkin wrote:
> > > Well I think we can add wrappers like virtio_dma_sync and so on.
> > > There are NOP for non-dma so passing the dma device is harmless.
> >
> > Yes, please.
> 
> 
> I am not sure I got this fully.
> 
> Are you mean this:
> https://lore.kernel.org/all/20230214072704.126660-8-xuanzhuo at
linux.alibaba.com/
> https://lore.kernel.org/all/20230214072704.126660-9-xuanzhuo at
linux.alibaba.com/
> 
> Then the driver must do dma operation(map and sync) by these virtio_dma_*
APIs.
> No care the device is non-dma device or dma device.
yes
> Then the AF_XDP must use these virtio_dma_* APIs for virtio device.
We'll worry about AF_XDP when the patch is posted.

-- 
MST