diff options
| -rw-r--r-- | drivers/net/virtio_net.c | 176 |
1 files changed, 168 insertions, 8 deletions
diff --git a/drivers/net/virtio_net.c b/drivers/net/virtio_net.c index a908f5e72677..c9c65948b71f 100644 --- a/drivers/net/virtio_net.c +++ b/drivers/net/virtio_net.c @@ -498,6 +498,12 @@ struct virtio_net_common_hdr { }; static void virtnet_sq_free_unused_buf(struct virtqueue *vq, void *buf); +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); +static void virtnet_receive_done(struct virtnet_info *vi, struct receive_queue *rq, + struct sk_buff *skb, u8 flags); static bool is_xdp_frame(void *ptr) { @@ -1062,6 +1068,124 @@ static void sg_fill_dma(struct scatterlist *sg, dma_addr_t addr, u32 len) sg->length = len; } +static struct xdp_buff *buf_to_xdp(struct virtnet_info *vi, + struct receive_queue *rq, void *buf, u32 len) +{ + struct xdp_buff *xdp; + u32 bufsize; + + xdp = (struct xdp_buff *)buf; + + bufsize = xsk_pool_get_rx_frame_size(rq->xsk_pool) + vi->hdr_len; + + if (unlikely(len > bufsize)) { + pr_debug("%s: rx error: len %u exceeds truesize %u\n", + vi->dev->name, len, bufsize); + DEV_STATS_INC(vi->dev, rx_length_errors); + xsk_buff_free(xdp); + return NULL; + } + + xsk_buff_set_size(xdp, len); + xsk_buff_dma_sync_for_cpu(xdp); + + return xdp; +} + +static struct sk_buff *xsk_construct_skb(struct receive_queue *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)) { + xsk_buff_free(xdp); + 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); + } + + xsk_buff_free(xdp); + + return skb; +} + +static struct sk_buff *virtnet_receive_xsk_small(struct net_device *dev, struct virtnet_info *vi, + struct receive_queue *rq, struct xdp_buff *xdp, + unsigned int *xdp_xmit, + struct virtnet_rq_stats *stats) +{ + struct bpf_prog *prog; + u32 ret; + + ret = XDP_PASS; + rcu_read_lock(); + prog = rcu_dereference(rq->xdp_prog); + if (prog) + ret = virtnet_xdp_handler(prog, xdp, dev, xdp_xmit, stats); + rcu_read_unlock(); + + switch (ret) { + case XDP_PASS: + return xsk_construct_skb(rq, xdp); + + case XDP_TX: + case XDP_REDIRECT: + return NULL; + + default: + /* drop packet */ + xsk_buff_free(xdp); + u64_stats_inc(&stats->drops); + return NULL; + } +} + +static void virtnet_receive_xsk_buf(struct virtnet_info *vi, struct receive_queue *rq, + void *buf, u32 len, + unsigned int *xdp_xmit, + struct virtnet_rq_stats *stats) +{ + struct net_device *dev = vi->dev; + struct sk_buff *skb = NULL; + struct xdp_buff *xdp; + u8 flags; + + len -= vi->hdr_len; + + u64_stats_add(&stats->bytes, len); + + xdp = buf_to_xdp(vi, rq, buf, len); + if (!xdp) + return; + + if (unlikely(len < ETH_HLEN)) { + pr_debug("%s: short packet %i\n", dev->name, len); + DEV_STATS_INC(dev, rx_length_errors); + xsk_buff_free(xdp); + return; + } + + flags = ((struct virtio_net_common_hdr *)(xdp->data - vi->hdr_len))->hdr.flags; + + if (!vi->mergeable_rx_bufs) + skb = virtnet_receive_xsk_small(dev, vi, rq, xdp, xdp_xmit, stats); + + if (skb) + virtnet_receive_done(vi, rq, skb, flags); +} + static int virtnet_add_recvbuf_xsk(struct virtnet_info *vi, struct receive_queue *rq, struct xsk_buff_pool *pool, gfp_t gfp) { @@ -2392,32 +2516,68 @@ static void refill_work(struct work_struct *work) } } -static int virtnet_receive(struct receive_queue *rq, int budget, - unsigned int *xdp_xmit) +static int virtnet_receive_xsk_bufs(struct virtnet_info *vi, + struct receive_queue *rq, + int budget, + unsigned int *xdp_xmit, + struct virtnet_rq_stats *stats) +{ + unsigned int len; + int packets = 0; + void *buf; + + while (packets < budget) { + buf = virtqueue_get_buf(rq->vq, &len); + if (!buf) + break; + + virtnet_receive_xsk_buf(vi, rq, buf, len, xdp_xmit, stats); + packets++; + } + + return packets; +} + +static int virtnet_receive_packets(struct virtnet_info *vi, + struct receive_queue *rq, + int budget, + unsigned int *xdp_xmit, + struct virtnet_rq_stats *stats) { - struct virtnet_info *vi = rq->vq->vdev->priv; - struct virtnet_rq_stats stats = {}; unsigned int len; int packets = 0; void *buf; - int i; if (!vi->big_packets || vi->mergeable_rx_bufs) { void *ctx; - while (packets < budget && (buf = virtnet_rq_get_buf(rq, &len, &ctx))) { - receive_buf(vi, rq, buf, len, ctx, xdp_xmit, &stats); + receive_buf(vi, rq, buf, len, ctx, xdp_xmit, stats); packets++; } } else { while (packets < budget && (buf = virtqueue_get_buf(rq->vq, &len)) != NULL) { - receive_buf(vi, rq, buf, len, NULL, xdp_xmit, &stats); + receive_buf(vi, rq, buf, len, NULL, xdp_xmit, stats); packets++; } } + return packets; +} + +static int virtnet_receive(struct receive_queue *rq, int budget, + unsigned int *xdp_xmit) +{ + struct virtnet_info *vi = rq->vq->vdev->priv; + struct virtnet_rq_stats stats = {}; + int i, packets; + + if (rq->xsk_pool) + packets = virtnet_receive_xsk_bufs(vi, rq, budget, xdp_xmit, &stats); + else + packets = virtnet_receive_packets(vi, rq, budget, xdp_xmit, &stats); + if (rq->vq->num_free > min((unsigned int)budget, virtqueue_get_vring_size(rq->vq)) / 2) { if (!try_fill_recv(vi, rq, GFP_ATOMIC)) { spin_lock(&vi->refill_lock); 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