Michael S. Tsirkin
2023-Jul-20 17:21 UTC
[PATCH vhost v11 05/10] virtio_ring: introduce virtqueue_dma_dev()
On Wed, Jul 19, 2023 at 11:22:42PM -0700, Christoph Hellwig wrote:> On Thu, Jul 13, 2023 at 10:51:59AM -0400, Michael S. Tsirkin wrote: > > On Thu, Jul 13, 2023 at 04:15:16AM -0700, Christoph Hellwig wrote: > > > On Mon, Jul 10, 2023 at 11:42:32AM +0800, Xuan Zhuo wrote: > > > > Added virtqueue_dma_dev() to get DMA device for virtio. Then the > > > > caller can do dma operation in advance. The purpose is to keep memory > > > > mapped across multiple add/get buf operations. > > > > > > This is just poking holes into the abstraction.. > > > > More specifically? > > Because now you expose a device that can't be used for the non-dma > mapping case and shoud be hidden.Ah, ok. 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. -- MST
Christoph Hellwig
2023-Jul-24 16:43 UTC
[PATCH vhost v11 05/10] virtio_ring: introduce virtqueue_dma_dev()
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.