On Mon, Oct 16, 2023 at 8:01 PM Xuan Zhuo <xuanzhuo@xxxxxxxxxxxxxxxxx> wrote: > > Implementing the logic of xsk rx. If this packet is not for XSK > determined in XDP, then we need to copy once to generate a SKB. > If it is for XSK, it is a zerocopy receive packet process. > > Signed-off-by: Xuan Zhuo <xuanzhuo@xxxxxxxxxxxxxxxxx> > --- > drivers/net/virtio/main.c | 14 ++-- > drivers/net/virtio/virtio_net.h | 4 ++ > drivers/net/virtio/xsk.c | 120 ++++++++++++++++++++++++++++++++ > drivers/net/virtio/xsk.h | 4 ++ > 4 files changed, 137 insertions(+), 5 deletions(-) > > diff --git a/drivers/net/virtio/main.c b/drivers/net/virtio/main.c > index 0e740447b142..003dd67ab707 100644 > --- a/drivers/net/virtio/main.c > +++ b/drivers/net/virtio/main.c > @@ -822,10 +822,10 @@ static void put_xdp_frags(struct xdp_buff *xdp) > } > } > > -static int virtnet_xdp_handler(struct bpf_prog *xdp_prog, struct xdp_buff *xdp, > - struct net_device *dev, > - unsigned int *xdp_xmit, > - struct virtnet_rq_stats *stats) > +int virtnet_xdp_handler(struct bpf_prog *xdp_prog, struct xdp_buff *xdp, > + struct net_device *dev, > + unsigned int *xdp_xmit, > + struct virtnet_rq_stats *stats) > { > struct xdp_frame *xdpf; > int err; > @@ -1589,13 +1589,17 @@ static void receive_buf(struct virtnet_info *vi, struct virtnet_rq *rq, > return; > } > > - if (vi->mergeable_rx_bufs) > + rcu_read_lock(); > + if (rcu_dereference(rq->xsk.pool)) > + skb = virtnet_receive_xsk(dev, vi, rq, buf, len, xdp_xmit, stats); > + else if (vi->mergeable_rx_bufs) > skb = receive_mergeable(dev, vi, rq, buf, ctx, len, xdp_xmit, > stats); > else if (vi->big_packets) > skb = receive_big(dev, vi, rq, buf, len, stats); > else > skb = receive_small(dev, vi, rq, buf, ctx, len, xdp_xmit, stats); > + rcu_read_unlock(); > > if (unlikely(!skb)) > return; > diff --git a/drivers/net/virtio/virtio_net.h b/drivers/net/virtio/virtio_net.h > index 6e71622fca45..fd7f34703c9b 100644 > --- a/drivers/net/virtio/virtio_net.h > +++ b/drivers/net/virtio/virtio_net.h > @@ -346,6 +346,10 @@ static inline bool virtnet_is_xdp_raw_buffer_queue(struct virtnet_info *vi, int > return false; > } > > +int virtnet_xdp_handler(struct bpf_prog *xdp_prog, struct xdp_buff *xdp, > + struct net_device *dev, > + unsigned int *xdp_xmit, > + struct virtnet_rq_stats *stats); > void virtnet_rx_pause(struct virtnet_info *vi, struct virtnet_rq *rq); > void virtnet_rx_resume(struct virtnet_info *vi, struct virtnet_rq *rq); > void virtnet_tx_pause(struct virtnet_info *vi, struct virtnet_sq *sq); > diff --git a/drivers/net/virtio/xsk.c b/drivers/net/virtio/xsk.c > index 841fb078882a..f1c64414fac9 100644 > --- a/drivers/net/virtio/xsk.c > +++ b/drivers/net/virtio/xsk.c > @@ -13,6 +13,18 @@ static void sg_fill_dma(struct scatterlist *sg, dma_addr_t addr, u32 len) > sg->length = len; > } > > +static unsigned int virtnet_receive_buf_num(struct virtnet_info *vi, char *buf) > +{ > + struct virtio_net_hdr_mrg_rxbuf *hdr; > + > + if (vi->mergeable_rx_bufs) { > + hdr = (struct virtio_net_hdr_mrg_rxbuf *)buf; > + return virtio16_to_cpu(vi->vdev, hdr->num_buffers); > + } > + > + return 1; > +} > + > static void virtnet_xsk_check_queue(struct virtnet_sq *sq) > { > struct virtnet_info *vi = sq->vq->vdev->priv; > @@ -37,6 +49,114 @@ static void virtnet_xsk_check_queue(struct virtnet_sq *sq) > netif_stop_subqueue(dev, qnum); > } > > +static void merge_drop_follow_xdp(struct net_device *dev, > + struct virtnet_rq *rq, > + u32 num_buf, > + struct virtnet_rq_stats *stats) > +{ > + struct xdp_buff *xdp; > + u32 len; > + > + while (num_buf-- > 1) { > + xdp = virtqueue_get_buf(rq->vq, &len); > + if (unlikely(!xdp)) { > + pr_debug("%s: rx error: %d buffers missing\n", > + dev->name, num_buf); > + dev->stats.rx_length_errors++; > + break; > + } > + stats->bytes += len; > + xsk_buff_free(xdp); > + } > +} > + > +static struct sk_buff *construct_skb(struct virtnet_rq *rq, > + struct xdp_buff *xdp) > +{ > + unsigned int metasize = xdp->data - xdp->data_meta; > + struct sk_buff *skb; > + unsigned int size; > + > + size = xdp->data_end - xdp->data_hard_start; > + skb = napi_alloc_skb(&rq->napi, size); > + if (unlikely(!skb)) > + return NULL; > + > + skb_reserve(skb, xdp->data_meta - xdp->data_hard_start); > + > + size = xdp->data_end - xdp->data_meta; > + memcpy(__skb_put(skb, size), xdp->data_meta, size); > + > + if (metasize) { > + __skb_pull(skb, metasize); > + skb_metadata_set(skb, metasize); > + } > + > + return skb; > +} > + > +struct sk_buff *virtnet_receive_xsk(struct net_device *dev, struct virtnet_info *vi, > + struct virtnet_rq *rq, void *buf, > + unsigned int len, unsigned int *xdp_xmit, > + struct virtnet_rq_stats *stats) > +{ I wonder if anything blocks us from reusing the existing XDP logic? Are there some subtle differences? Thanks _______________________________________________ Virtualization mailing list Virtualization@xxxxxxxxxxxxxxxxxxxxxxxxxx https://lists.linuxfoundation.org/mailman/listinfo/virtualization