[PATCH net-next v2 17/21] virtio_net: xsk: rx: skip dma unmap when rq is bind with AF_XDP

Xuan Zhuo
2023-11-07T03:12:52Z

When rq is bound with AF_XDP, the buffer dma is managed
by the AF_XDP APIs. So the buffer got from the virtio core should
skip the dma unmap operation.

Signed-off-by: Xuan Zhuo <xuanzhuo@linux.alibaba.com>
---
drivers/net/virtio/main.c | 8 +++++---
drivers/net/virtio/virtio_net.h | 3 +++
drivers/net/virtio/xsk.c | 1 +
3 files changed, 9 insertions(+), 3 deletions(-)

diff --git a/drivers/net/virtio/main.c b/drivers/net/virtio/main.c
index 15943a22e17d..a318b2533b94 100644
--- a/drivers/net/virtio/main.c
+++ b/drivers/net/virtio/main.c
@@ -430,7 +430,7 @@ static void *virtnet_rq_get_buf(struct virtnet_rq *rq, u32 *len, void **ctx)
void *buf;

buf = virtqueue_get_buf_ctx(rq->vq, len, ctx);
- if (buf && rq->do_dma)
+ if (buf && rq->do_dma_unmap)
virtnet_rq_unmap(rq, buf, *len);

return buf;
@@ -561,8 +561,10 @@ static void virtnet_set_premapped(struct virtnet_info *vi)

/* disable for big mode */
if (vi->mergeable_rx_bufs || !vi->big_packets) {
- if (!virtqueue_set_dma_premapped(vi->rq[i].vq))
+ if (!virtqueue_set_dma_premapped(vi->rq[i].vq)) {
vi->rq[i].do_dma = true;
+ vi->rq[i].do_dma_unmap = true;
+ }
}
}
}
@@ -3944,7 +3946,7 @@ void virtnet_rq_free_unused_buf(struct virtqueue *vq, void *buf)

rq = &vi->rq[i];

- if (rq->do_dma)
+ if (rq->do_dma_unmap)
virtnet_rq_unmap(rq, buf, 0);

virtnet_rq_free_buf(vi, rq, buf);
diff --git a/drivers/net/virtio/virtio_net.h b/drivers/net/virtio/virtio_net.h
index 1242785e311e..2005d0cd22e2 100644
--- a/drivers/net/virtio/virtio_net.h
+++ b/drivers/net/virtio/virtio_net.h
@@ -135,6 +135,9 @@ struct virtnet_rq {
/* Do dma by self */
bool do_dma;

+ /* Do dma unmap after getting buf from virtio core. */
+ bool do_dma_unmap;
+
struct {
struct xsk_buff_pool *pool;

diff --git a/drivers/net/virtio/xsk.c b/drivers/net/virtio/xsk.c
index e737c3353212..b09c473c29fb 100644
--- a/drivers/net/virtio/xsk.c
+++ b/drivers/net/virtio/xsk.c
@@ -210,6 +210,7 @@ static int virtnet_rq_bind_xsk_pool(struct virtnet_info *vi, struct virtnet_rq *
xdp_rxq_info_unreg(&rq->xsk.xdp_rxq);

rq->xsk.pool = pool;
+ rq->do_dma_unmap = !pool;

virtnet_rx_resume(vi, rq);

--
2.32.0.3.g01195cf9f