On Wed, Mar 30, 2022 at 05:03:32PM +0800, Xuan Zhuo
wrote:> On Wed, 30 Mar 2022 16:38:18 +0800, Jason Wang <jasowang at
redhat.com> wrote:
> > On Wed, Mar 30, 2022 at 2:59 PM Xuan Zhuo <xuanzhuo at
linux.alibaba.com> wrote:
> > >
> > > On Wed, 30 Mar 2022 14:56:17 +0800, Jason Wang <jasowang at
redhat.com> wrote:
> > > > On Wed, Mar 30, 2022 at 2:34 PM Michael S. Tsirkin <mst
at redhat.com> wrote:
> > > > >
> > > > > On Thu, Feb 24, 2022 at 07:03:53PM +0800, Xuan Zhuo
wrote:
> > > > > > virtqueue_add() only supports virtual addresses,
dma is completed in
> > > > > > virtqueue_add().
> > > > > >
> > > > > > In some scenarios (such as the AF_XDP scenario),
DMA is completed in advance, so
> > > > > > it is necessary for us to support passing the DMA
address to virtqueue_add().
> > > > >
> > > > > I picked up a couple of patches. Others are waiting for
some acks
> > > > > (Jason?) and improved commit logs for documentation.
> > > >
> > > > I will review them.
> > >
> > > hi, the core code of premapped, I will merge it into 'virtio
pci support
> > > VIRTIO_F_RING_RESET' because this function will be used when
reusing the buffer
> > > after resize.
> >
> > I still prefer not to do that.
> >
> > We can make rest work for resize first and add pre mapping on top. It
> > will simplify the review.
>
> Yes, I am also worried about the review problem, the number of my local
resize
> patch has reached 44 (including reuse bufs).
>
> hi, Michael, can we implement resize on top of v8 first? (drop unused bufs
directly)
>
> Then we implement premmapd and reuse the bufs after resize.
>
> We need to get the address (DMA address) and len from the reset ring and
submit
> it to the new vq through virtqueue_add(). So let virtqueue_add() support
> premapped first.
>
> Thanks.
Not sure I understand.
So the plan is
- remap
- resize on top
?
>
> >
> > Thanks
> >
> > >
> > > Thanks.
> > >
> > >
> > > >
> > > > Thanks
> > > >
> > > > >
> > > > > Thanks!
> > > > >
> > > > > > v2:
> > > > > > 1. rename predma -> premapped
> > > > > > 2. virtio net xdp tx use virtio dma api
> > > > > >
> > > > > > v1:
> > > > > > 1. All sgs requested at one time are required
to be unified PREDMA, and several
> > > > > > of them are not supported to be PREDMA
> > > > > > 2. virtio_dma_map() is removed from this patch
set and will be submitted
> > > > > > together with the next time AF_XDP supports
virtio dma
> > > > > > 3. Added patch #2 #3 to remove the check for
flags when performing unmap
> > > > > > indirect desc
> > > > > >
> > > > > > Xuan Zhuo (9):
> > > > > > virtio_ring: rename vring_unmap_state_packed()
to
> > > > > > vring_unmap_extra_packed()
> > > > > > virtio_ring: remove flags check for unmap split
indirect desc
> > > > > > virtio_ring: remove flags check for unmap packed
indirect desc
> > > > > > virtio_ring: virtqueue_add() support premapped
> > > > > > virtio_ring: split: virtqueue_add_split()
support premapped
> > > > > > virtio_ring: packed: virtqueue_add_packed()
support premapped
> > > > > > virtio_ring: add api virtio_dma_map() for
advance dma
> > > > > > virtio_ring: introduce
virtqueue_add_outbuf_premapped()
> > > > > > virtio_net: xdp xmit use virtio dma api
> > > > > >
> > > > > > drivers/net/virtio_net.c | 42 +++++-
> > > > > > drivers/virtio/virtio_ring.c | 280
++++++++++++++++++++++++++---------
> > > > > > include/linux/virtio.h | 12 ++
> > > > > > 3 files changed, 254 insertions(+), 80
deletions(-)
> > > > > >
> > > > > > --
> > > > > > 2.31.0
> > > > >
> > > >
> > >
> >