On Tue, Jun 11, 2024 at 07:41:41PM +0800, Xuan Zhuo wrote:
> This patch implement the logic of bind/unbind xsk pool to sq and rq.
>
> Signed-off-by: Xuan Zhuo <xuanzhuo@xxxxxxxxxxxxxxxxx>
I'd just squash with previous patch. This one is hard to review in
isolation.
> ---
> drivers/net/virtio_net.c | 199 +++++++++++++++++++++++++++++++++++++++
> 1 file changed, 199 insertions(+)
>
> diff --git a/drivers/net/virtio_net.c b/drivers/net/virtio_net.c
> index 4968ab7eb5a4..c82a0691632c 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,
> @@ -320,6 +323,12 @@ 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 */
> @@ -371,6 +380,13 @@ 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
> @@ -5168,6 +5184,187 @@ 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)
> {
> @@ -5293,6 +5490,8 @@ 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
