This patch implement the logic of bind/unbind xsk pool to sq and rq. Signed-off-by: Xuan Zhuo <xuanzhuo@xxxxxxxxxxxxxxxxx> --- drivers/net/virtio_net.c | 201 ++++++++++++++++++++++++++++++++++++++- 1 file changed, 200 insertions(+), 1 deletion(-) diff --git a/drivers/net/virtio_net.c b/drivers/net/virtio_net.c index 88ab9ea1646f..35fd8bca7fcf 100644 --- a/drivers/net/virtio_net.c +++ b/drivers/net/virtio_net.c @@ -26,6 +26,7 @@ #include <net/netdev_rx_queue.h> #include <net/netdev_queues.h> #include <uapi/linux/virtio_ring.h> +#include <net/xdp_sock_drv.h> static int napi_weight = NAPI_POLL_WEIGHT; module_param(napi_weight, int, 0444); @@ -57,6 +58,8 @@ DECLARE_EWMA(pkt_len, 0, 64) #define VIRTNET_DRIVER_VERSION "1.0.0" +static struct virtio_net_hdr_mrg_rxbuf xsk_hdr; + static const unsigned long guest_offloads[] = { VIRTIO_NET_F_GUEST_TSO4, VIRTIO_NET_F_GUEST_TSO6, @@ -321,6 +324,12 @@ struct send_queue { bool premapped; struct virtnet_sq_dma_info dmainfo; + + struct { + struct xsk_buff_pool *pool; + + dma_addr_t hdr_dma_address; + } xsk; }; /* Internal representation of a receive virtqueue */ @@ -372,6 +381,13 @@ struct receive_queue { /* Record the last dma info to free after new pages is allocated. */ struct virtnet_rq_dma *last_dma; + + struct { + struct xsk_buff_pool *pool; + + /* xdp rxq used by xsk */ + struct xdp_rxq_info xdp_rxq; + } xsk; }; /* This structure can contain rss message with maximum settings for indirection table and keysize @@ -695,7 +711,7 @@ static void virtnet_sq_free_dma_meta(struct send_queue *sq) /* This function must be called immediately after creating the vq, or after vq * reset, and before adding any buffers to it. */ -static __maybe_unused int virtnet_sq_set_premapped(struct send_queue *sq, bool premapped) +static int virtnet_sq_set_premapped(struct send_queue *sq, bool premapped) { if (premapped) { int r; @@ -5177,6 +5193,187 @@ static int virtnet_restore_guest_offloads(struct virtnet_info *vi) return virtnet_set_guest_offloads(vi, offloads); } +static int virtnet_rq_bind_xsk_pool(struct virtnet_info *vi, struct receive_queue *rq, + struct xsk_buff_pool *pool) +{ + int err, qindex; + + qindex = rq - vi->rq; + + if (pool) { + err = xdp_rxq_info_reg(&rq->xsk.xdp_rxq, vi->dev, qindex, rq->napi.napi_id); + if (err < 0) + return err; + + err = xdp_rxq_info_reg_mem_model(&rq->xsk.xdp_rxq, + MEM_TYPE_XSK_BUFF_POOL, NULL); + if (err < 0) { + xdp_rxq_info_unreg(&rq->xsk.xdp_rxq); + return err; + } + + xsk_pool_set_rxq_info(pool, &rq->xsk.xdp_rxq); + } + + virtnet_rx_pause(vi, rq); + + err = virtqueue_reset(rq->vq, virtnet_rq_unmap_free_buf); + if (err) { + netdev_err(vi->dev, "reset rx fail: rx queue index: %d err: %d\n", qindex, err); + + pool = NULL; + } + + if (!pool) + xdp_rxq_info_unreg(&rq->xsk.xdp_rxq); + + rq->xsk.pool = pool; + + virtnet_rx_resume(vi, rq); + + return err; +} + +static int virtnet_sq_bind_xsk_pool(struct virtnet_info *vi, + struct send_queue *sq, + struct xsk_buff_pool *pool) +{ + int err, qindex; + + qindex = sq - vi->sq; + + virtnet_tx_pause(vi, sq); + + err = virtqueue_reset(sq->vq, virtnet_sq_free_unused_buf); + if (err) + netdev_err(vi->dev, "reset tx fail: tx queue index: %d err: %d\n", qindex, err); + else + err = virtnet_sq_set_premapped(sq, !!pool); + + if (err) + pool = NULL; + + sq->xsk.pool = pool; + + virtnet_tx_resume(vi, sq); + + return err; +} + +static int virtnet_xsk_pool_enable(struct net_device *dev, + struct xsk_buff_pool *pool, + u16 qid) +{ + struct virtnet_info *vi = netdev_priv(dev); + struct receive_queue *rq; + struct send_queue *sq; + struct device *dma_dev; + dma_addr_t hdr_dma; + int err; + + /* In big_packets mode, xdp cannot work, so there is no need to + * initialize xsk of rq. + * + * Support for small mode firstly. + */ + if (vi->big_packets) + return -ENOENT; + + if (qid >= vi->curr_queue_pairs) + return -EINVAL; + + sq = &vi->sq[qid]; + rq = &vi->rq[qid]; + + /* xsk tx zerocopy depend on the tx napi. + * + * All xsk packets are actually consumed and sent out from the xsk tx + * queue under the tx napi mechanism. + */ + if (!sq->napi.weight) + return -EPERM; + + /* For the xsk, the tx and rx should have the same device. But + * vq->dma_dev allows every vq has the respective dma dev. So I check + * the dma dev of vq and sq is the same dev. + */ + if (virtqueue_dma_dev(rq->vq) != virtqueue_dma_dev(sq->vq)) + return -EPERM; + + dma_dev = virtqueue_dma_dev(rq->vq); + if (!dma_dev) + return -EPERM; + + hdr_dma = dma_map_single(dma_dev, &xsk_hdr, vi->hdr_len, DMA_TO_DEVICE); + if (dma_mapping_error(dma_dev, hdr_dma)) + return -ENOMEM; + + err = xsk_pool_dma_map(pool, dma_dev, 0); + if (err) + goto err_xsk_map; + + err = virtnet_rq_bind_xsk_pool(vi, rq, pool); + if (err) + goto err_rq; + + err = virtnet_sq_bind_xsk_pool(vi, sq, pool); + if (err) + goto err_sq; + + /* Now, we do not support tx offset, so all the tx virtnet hdr is zero. + * So all the tx packets can share a single hdr. + */ + sq->xsk.hdr_dma_address = hdr_dma; + + return 0; + +err_sq: + virtnet_rq_bind_xsk_pool(vi, rq, NULL); +err_rq: + xsk_pool_dma_unmap(pool, 0); +err_xsk_map: + dma_unmap_single(dma_dev, hdr_dma, vi->hdr_len, DMA_TO_DEVICE); + return err; +} + +static int virtnet_xsk_pool_disable(struct net_device *dev, u16 qid) +{ + struct virtnet_info *vi = netdev_priv(dev); + struct xsk_buff_pool *pool; + struct device *dma_dev; + struct receive_queue *rq; + struct send_queue *sq; + int err1, err2; + + if (qid >= vi->curr_queue_pairs) + return -EINVAL; + + sq = &vi->sq[qid]; + rq = &vi->rq[qid]; + + pool = sq->xsk.pool; + + err1 = virtnet_sq_bind_xsk_pool(vi, sq, NULL); + err2 = virtnet_rq_bind_xsk_pool(vi, rq, NULL); + + xsk_pool_dma_unmap(pool, 0); + + dma_dev = virtqueue_dma_dev(rq->vq); + + dma_unmap_single(dma_dev, sq->xsk.hdr_dma_address, vi->hdr_len, DMA_TO_DEVICE); + + return err1 | err2; +} + +static int virtnet_xsk_pool_setup(struct net_device *dev, struct netdev_bpf *xdp) +{ + if (xdp->xsk.pool) + return virtnet_xsk_pool_enable(dev, xdp->xsk.pool, + xdp->xsk.queue_id); + else + return virtnet_xsk_pool_disable(dev, xdp->xsk.queue_id); +} + static int virtnet_xdp_set(struct net_device *dev, struct bpf_prog *prog, struct netlink_ext_ack *extack) { @@ -5302,6 +5499,8 @@ static int virtnet_xdp(struct net_device *dev, struct netdev_bpf *xdp) switch (xdp->command) { case XDP_SETUP_PROG: return virtnet_xdp_set(dev, xdp->prog, xdp->extack); + case XDP_SETUP_XSK_POOL: + return virtnet_xsk_pool_setup(dev, xdp); default: return -EINVAL; } -- 2.32.0.3.g01195cf9f