From patchwork Tue Nov 22 07:43:44 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Heng Qi X-Patchwork-Id: 13051979 X-Patchwork-Delegate: kuba@kernel.org Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 8E354C43217 for ; Tue, 22 Nov 2022 07:44:08 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232545AbiKVHoG (ORCPT ); Tue, 22 Nov 2022 02:44:06 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:54246 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232493AbiKVHoC (ORCPT ); Tue, 22 Nov 2022 02:44:02 -0500 Received: from out30-133.freemail.mail.aliyun.com (out30-133.freemail.mail.aliyun.com [115.124.30.133]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 5D606317CA; Mon, 21 Nov 2022 23:43:59 -0800 (PST) X-Alimail-AntiSpam: AC=PASS;BC=-1|-1;BR=01201311R191e4;CH=green;DM=||false|;DS=||;FP=0|-1|-1|-1|0|-1|-1|-1;HT=ay29a033018046049;MF=hengqi@linux.alibaba.com;NM=1;PH=DS;RN=11;SR=0;TI=SMTPD_---0VVR5.Fl_1669103035; Received: from localhost(mailfrom:hengqi@linux.alibaba.com fp:SMTPD_---0VVR5.Fl_1669103035) by smtp.aliyun-inc.com; Tue, 22 Nov 2022 15:43:56 +0800 From: Heng Qi To: netdev@vger.kernel.org, bpf@vger.kernel.org Cc: Jason Wang , "Michael S. Tsirkin" , Paolo Abeni , Jakub Kicinski , John Fastabend , "David S. Miller" , Daniel Borkmann , Alexei Starovoitov , Eric Dumazet Subject: [RFC PATCH 5/9] virtio_net: build xdp_buff with multi buffers Date: Tue, 22 Nov 2022 15:43:44 +0800 Message-Id: <20221122074348.88601-6-hengqi@linux.alibaba.com> X-Mailer: git-send-email 2.19.1.6.gb485710b In-Reply-To: <20221122074348.88601-1-hengqi@linux.alibaba.com> References: <20221122074348.88601-1-hengqi@linux.alibaba.com> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org X-Patchwork-Delegate: kuba@kernel.org X-Patchwork-State: RFC Support xdp for multi buffer packets. Putting the first buffer as the linear part for xdp_buff, and the rest of the buffers as non-linear fragments to struct skb_shared_info in the tailroom belonging to xdp_buff. Signed-off-by: Heng Qi Reviewed-by: Xuan Zhuo --- drivers/net/virtio_net.c | 74 ++++++++++++++++++++++++++++++++++++++++ 1 file changed, 74 insertions(+) diff --git a/drivers/net/virtio_net.c b/drivers/net/virtio_net.c index cd65f85d5075..20784b1d8236 100644 --- a/drivers/net/virtio_net.c +++ b/drivers/net/virtio_net.c @@ -911,6 +911,80 @@ static struct sk_buff *receive_big(struct net_device *dev, return NULL; } +static int virtnet_build_xdp_buff(struct net_device *dev, + struct virtnet_info *vi, + struct receive_queue *rq, + struct xdp_buff *xdp, + void *buf, + unsigned int len, + unsigned int frame_sz, + u16 *num_buf, + unsigned int *xdp_frags_truesize, + struct virtnet_rq_stats *stats) +{ + unsigned int tailroom = SKB_DATA_ALIGN(sizeof(struct skb_shared_info)); + struct virtio_net_hdr_mrg_rxbuf *hdr = buf; + unsigned int truesize, headroom; + struct skb_shared_info *shinfo; + unsigned int xdp_frags_truesz = 0; + unsigned int cur_frag_size; + struct page *page; + skb_frag_t *frag; + int offset; + void *ctx; + + xdp_init_buff(xdp, frame_sz, &rq->xdp_rxq); + xdp_prepare_buff(xdp, buf - VIRTIO_XDP_HEADROOM, + VIRTIO_XDP_HEADROOM + vi->hdr_len, len - vi->hdr_len, true); + shinfo = xdp_get_shared_info_from_buff(xdp); + shinfo->nr_frags = 0; + shinfo->xdp_frags_size = 0; + + if ((*num_buf - 1) > MAX_SKB_FRAGS) + return -EINVAL; + + while ((--*num_buf) >= 1) { + buf = virtqueue_get_buf_ctx(rq->vq, &len, &ctx); + if (unlikely(!buf)) { + pr_debug("%s: rx error: %d buffers out of %d missing\n", + dev->name, *num_buf, + virtio16_to_cpu(vi->vdev, hdr->num_buffers)); + dev->stats.rx_length_errors++; + return -EINVAL; + } + + if (!xdp_buff_has_frags(xdp)) + xdp_buff_set_frags_flag(xdp); + + stats->bytes += len; + page = virt_to_head_page(buf); + offset = buf - page_address(page); + truesize = mergeable_ctx_to_truesize(ctx); + headroom = mergeable_ctx_to_headroom(ctx); + + cur_frag_size = truesize + (headroom ? (headroom + tailroom) : 0); + xdp_frags_truesz += cur_frag_size; + if (unlikely(len > truesize || cur_frag_size > PAGE_SIZE)) { + pr_debug("%s: rx error: len %u exceeds truesize %lu\n", + dev->name, len, (unsigned long)ctx); + dev->stats.rx_length_errors++; + return -EINVAL; + } + + frag = &shinfo->frags[shinfo->nr_frags++]; + __skb_frag_set_page(frag, page); + skb_frag_off_set(frag, offset); + skb_frag_size_set(frag, len); + if (page_is_pfmemalloc(page)) + xdp_buff_set_frag_pfmemalloc(xdp); + + shinfo->xdp_frags_size += len; + } + + *xdp_frags_truesize = xdp_frags_truesz; + return 0; +} + static struct sk_buff *receive_mergeable(struct net_device *dev, struct virtnet_info *vi, struct receive_queue *rq,