From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from lindbergh.monkeyblade.net (lindbergh.monkeyblade.net [23.128.96.19]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id B28F7101CA; Fri, 20 Oct 2023 08:05:17 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; dkim=none Received: from out30-118.freemail.mail.aliyun.com (out30-118.freemail.mail.aliyun.com [115.124.30.118]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 6294BE8; Fri, 20 Oct 2023 01:05:14 -0700 (PDT) X-Alimail-AntiSpam:AC=PASS;BC=-1|-1;BR=01201311R151e4;CH=green;DM=||false|;DS=||;FP=0|-1|-1|-1|0|-1|-1|-1;HT=ay29a033018045176;MF=xuanzhuo@linux.alibaba.com;NM=1;PH=DS;RN=13;SR=0;TI=SMTPD_---0VuWbBuF_1697789110; Received: from localhost(mailfrom:xuanzhuo@linux.alibaba.com fp:SMTPD_---0VuWbBuF_1697789110) by smtp.aliyun-inc.com; Fri, 20 Oct 2023 16:05:10 +0800 Message-ID: <1697786930.9987535-2-xuanzhuo@linux.alibaba.com> Subject: Re: [PATCH net-next v1 09/19] virtio_net: xsk: bind/unbind xsk Date: Fri, 20 Oct 2023 15:28:50 +0800 From: Xuan Zhuo To: Jason Wang Cc: netdev@vger.kernel.org, "David S. Miller" , Eric Dumazet , Jakub Kicinski , Paolo Abeni , "Michael S. Tsirkin" , Alexei Starovoitov , Daniel Borkmann , Jesper Dangaard Brouer , John Fastabend , virtualization@lists.linux-foundation.org, bpf@vger.kernel.org References: <20231016120033.26933-1-xuanzhuo@linux.alibaba.com> <20231016120033.26933-10-xuanzhuo@linux.alibaba.com> In-Reply-To: Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable Precedence: bulk X-Mailing-List: bpf@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: On Fri, 20 Oct 2023 14:51:15 +0800, Jason Wang wrote: > On Mon, Oct 16, 2023 at 8:01=E2=80=AFPM Xuan Zhuo wrote: > > > > This patch implement the logic of bind/unbind xsk pool to sq and rq. > > > > Signed-off-by: Xuan Zhuo > > --- > > drivers/net/virtio/Makefile | 2 +- > > drivers/net/virtio/main.c | 10 +- > > drivers/net/virtio/virtio_net.h | 18 ++++ > > drivers/net/virtio/xsk.c | 186 ++++++++++++++++++++++++++++++++ > > drivers/net/virtio/xsk.h | 7 ++ > > 5 files changed, 216 insertions(+), 7 deletions(-) > > create mode 100644 drivers/net/virtio/xsk.c > > create mode 100644 drivers/net/virtio/xsk.h > > > > diff --git a/drivers/net/virtio/Makefile b/drivers/net/virtio/Makefile > > index 15ed7c97fd4f..8c2a884d2dba 100644 > > --- a/drivers/net/virtio/Makefile > > +++ b/drivers/net/virtio/Makefile > > @@ -5,4 +5,4 @@ > > > > obj-$(CONFIG_VIRTIO_NET) +=3D virtio_net.o > > > > -virtio_net-y :=3D main.o > > +virtio_net-y :=3D main.o xsk.o > > diff --git a/drivers/net/virtio/main.c b/drivers/net/virtio/main.c > > index 02d27101fef1..38733a782f12 100644 > > --- a/drivers/net/virtio/main.c > > +++ b/drivers/net/virtio/main.c > > @@ -8,7 +8,6 @@ > > #include > > #include > > #include > > -#include > > #include > > #include > > #include > > @@ -139,9 +138,6 @@ struct virtio_net_common_hdr { > > }; > > }; > > > > -static void virtnet_rq_free_unused_buf(struct virtqueue *vq, void *buf= ); > > -static void virtnet_sq_free_unused_buf(struct virtqueue *vq, void *buf= ); > > - > > static void *xdp_to_ptr(struct xdp_frame *ptr) > > { > > return (void *)((unsigned long)ptr | VIRTIO_XDP_FLAG); > > @@ -3664,6 +3660,8 @@ static int virtnet_xdp(struct net_device *dev, st= ruct 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; > > } > > @@ -3849,7 +3847,7 @@ static void free_receive_page_frags(struct virtne= t_info *vi) > > } > > } > > > > -static void virtnet_sq_free_unused_buf(struct virtqueue *vq, void *buf) > > +void virtnet_sq_free_unused_buf(struct virtqueue *vq, void *buf) > > { > > if (!virtnet_is_xdp_frame(buf)) > > dev_kfree_skb(buf); > > @@ -3857,7 +3855,7 @@ static void virtnet_sq_free_unused_buf(struct vir= tqueue *vq, void *buf) > > xdp_return_frame(virtnet_ptr_to_xdp(buf)); > > } > > > > -static void virtnet_rq_free_unused_buf(struct virtqueue *vq, void *buf) > > +void virtnet_rq_free_unused_buf(struct virtqueue *vq, void *buf) > > { > > struct virtnet_info *vi =3D vq->vdev->priv; > > int i =3D vq2rxq(vq); > > diff --git a/drivers/net/virtio/virtio_net.h b/drivers/net/virtio/virti= o_net.h > > index cc742756e19a..9e69b6c5921b 100644 > > --- a/drivers/net/virtio/virtio_net.h > > +++ b/drivers/net/virtio/virtio_net.h > > @@ -5,6 +5,8 @@ > > > > #include > > #include > > +#include > > +#include > > > > #define VIRTIO_XDP_FLAG BIT(0) > > #define VIRTIO_XMIT_DATA_MASK (VIRTIO_XDP_FLAG) > > @@ -94,6 +96,11 @@ struct virtnet_sq { > > bool do_dma; > > > > struct virtnet_sq_dma_head dmainfo; > > + struct { > > + struct xsk_buff_pool __rcu *pool; > > + > > + dma_addr_t hdr_dma_address; > > + } xsk; > > }; > > > > /* Internal representation of a receive virtqueue */ > > @@ -134,6 +141,13 @@ struct virtnet_rq { > > > > /* Do dma by self */ > > bool do_dma; > > + > > + struct { > > + struct xsk_buff_pool __rcu *pool; > > + > > + /* xdp rxq used by xsk */ > > + struct xdp_rxq_info xdp_rxq; > > + } xsk; > > }; > > > > struct virtnet_info { > > @@ -218,6 +232,8 @@ struct virtnet_info { > > struct failover *failover; > > }; > > > > +#include "xsk.h" > > + > > Any reason we don't do it with other headers? Because xsk.h will reference the struct virtnet_sq..., if we put xsk.h at the start of virtio_net.h, the gcc will not happy. But the virtio-net.h references the api(virtnet_ptr_to_xsk) of the xsk.h. > > > static inline bool virtnet_is_xdp_frame(void *ptr) > > { > > return (unsigned long)ptr & VIRTIO_XDP_FLAG; > > @@ -308,4 +324,6 @@ void virtnet_rx_pause(struct virtnet_info *vi, stru= ct 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); > > void virtnet_tx_resume(struct virtnet_info *vi, struct virtnet_sq *sq); > > +void virtnet_sq_free_unused_buf(struct virtqueue *vq, void *buf); > > +void virtnet_rq_free_unused_buf(struct virtqueue *vq, void *buf); > > #endif > > diff --git a/drivers/net/virtio/xsk.c b/drivers/net/virtio/xsk.c > > new file mode 100644 > > index 000000000000..dddd01962a3f > > --- /dev/null > > +++ b/drivers/net/virtio/xsk.c > > @@ -0,0 +1,186 @@ [...] > > + > > + if (!rq->do_dma || !sq->do_dma) > > + return -EPERM; > > + > > + if (virtqueue_dma_dev(rq->vq) !=3D virtqueue_dma_dev(sq->vq)) > > + return -EPERM; > > Any reason we need this check? Is there any code that has this > assumption? E.g dma sync in XDP_TX? For the xsk, the tx and rx should have the same dev. 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. > > > + > > + dma_dev =3D virtqueue_dma_dev(rq->vq); > > + if (!dma_dev) > > + return -EPERM; > > + > > + hdr_dma =3D dma_map_single(dma_dev, &xsk_hdr, vi->hdr_len, DMA_= TO_DEVICE); > > + if (dma_mapping_error(dma_dev, hdr_dma)) > > + return -ENOMEM; > > + > > + err =3D xsk_pool_dma_map(pool, dma_dev, 0); > > + if (err) > > + goto err_xsk_map; > > + > > + err =3D virtnet_rq_bind_xsk_pool(vi, rq, pool); > > + if (err) > > + goto err_rq; > > + > > + err =3D virtnet_sq_bind_xsk_pool(vi, sq, pool); > > + if (err) > > + goto err_sq; > > + > > + sq->xsk.hdr_dma_address =3D hdr_dma; > > I think we probably need some comments to explain why a single hdr can > work. Like it means we use the same hdr for all XSK packets? Will fix. > > > + > > + 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 =3D netdev_priv(dev); > > + struct xsk_buff_pool *pool; > > + struct device *dma_dev; > > + struct virtnet_rq *rq; > > + struct virtnet_sq *sq; > > + int err1, err2; > > + > > + if (qid >=3D vi->curr_queue_pairs) > > + return -EINVAL; > > + > > + sq =3D &vi->sq[qid]; > > + rq =3D &vi->rq[qid]; > > + > > + dma_dev =3D virtqueue_dma_dev(rq->vq); > > + > > + /* Sync with the XSK wakeup and NAPI. */ > > + synchronize_net(); > > Any reason we couldn't do bind_xsk_pool(NULL) here? It seems easier. Do you mean rcu_assign_pointer() is enough? Let me check it. Thanks > > Thanks > > > > + > > + dma_unmap_single(dma_dev, sq->xsk.hdr_dma_address, vi->hdr_len,= DMA_TO_DEVICE); > > + > > + rcu_read_lock(); > > + pool =3D rcu_dereference(sq->xsk.pool); > > + xsk_pool_dma_unmap(pool, 0); > > + rcu_read_unlock(); > > + > > + err1 =3D virtnet_sq_bind_xsk_pool(vi, sq, NULL); > > + err2 =3D virtnet_rq_bind_xsk_pool(vi, rq, NULL); > > + > > + return err1 | err2; > > +} > > + > > +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); > > +} > > diff --git a/drivers/net/virtio/xsk.h b/drivers/net/virtio/xsk.h > > new file mode 100644 > > index 000000000000..1918285c310c > > --- /dev/null > > +++ b/drivers/net/virtio/xsk.h > > @@ -0,0 +1,7 @@ > > +/* SPDX-License-Identifier: GPL-2.0-or-later */ > > + > > +#ifndef __XSK_H__ > > +#define __XSK_H__ > > + > > +int virtnet_xsk_pool_setup(struct net_device *dev, struct netdev_bpf *= xdp); > > +#endif > > -- > > 2.32.0.3.g01195cf9f > > >