From patchwork Tue Dec 20 14:14:49 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Heng Qi X-Patchwork-Id: 13077924 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 3E61FC4332F for ; Tue, 20 Dec 2022 14:15:18 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S233892AbiLTOPQ (ORCPT ); Tue, 20 Dec 2022 09:15:16 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:43322 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S233857AbiLTOPE (ORCPT ); Tue, 20 Dec 2022 09:15:04 -0500 Received: from out30-44.freemail.mail.aliyun.com (out30-44.freemail.mail.aliyun.com [115.124.30.44]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id EC997E4F; Tue, 20 Dec 2022 06:15:02 -0800 (PST) X-Alimail-AntiSpam: AC=PASS;BC=-1|-1;BR=01201311R101e4;CH=green;DM=||false|;DS=||;FP=0|-1|-1|-1|0|-1|-1|-1;HT=ay29a033018045168;MF=hengqi@linux.alibaba.com;NM=1;PH=DS;RN=12;SR=0;TI=SMTPD_---0VXlgNFe_1671545699; Received: from localhost(mailfrom:hengqi@linux.alibaba.com fp:SMTPD_---0VXlgNFe_1671545699) by smtp.aliyun-inc.com; Tue, 20 Dec 2022 22:15:00 +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 , Xuan Zhuo Subject: [PATCH v2 9/9] virtio_net: support multi-buffer xdp Date: Tue, 20 Dec 2022 22:14:49 +0800 Message-Id: <20221220141449.115918-10-hengqi@linux.alibaba.com> X-Mailer: git-send-email 2.19.1.6.gb485710b In-Reply-To: <20221220141449.115918-1-hengqi@linux.alibaba.com> References: <20221220141449.115918-1-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 Driver can pass the skb to stack by build_skb_from_xdp_buff(). Driver forwards multi-buffer packets using the send queue when XDP_TX and XDP_REDIRECT, and clears the reference of multi pages when XDP_DROP. Signed-off-by: Heng Qi Reviewed-by: Xuan Zhuo Acked-by: Jason Wang --- drivers/net/virtio_net.c | 65 ++++++---------------------------------- 1 file changed, 9 insertions(+), 56 deletions(-) diff --git a/drivers/net/virtio_net.c b/drivers/net/virtio_net.c index 398ffe2a5084..daa380b9d1cc 100644 --- a/drivers/net/virtio_net.c +++ b/drivers/net/virtio_net.c @@ -1074,7 +1074,6 @@ static struct sk_buff *receive_mergeable(struct net_device *dev, struct bpf_prog *xdp_prog; unsigned int truesize = mergeable_ctx_to_truesize(ctx); unsigned int headroom = mergeable_ctx_to_headroom(ctx); - unsigned int metasize = 0; unsigned int frame_sz; int err; @@ -1165,63 +1164,22 @@ static struct sk_buff *receive_mergeable(struct net_device *dev, switch (act) { case XDP_PASS: - metasize = xdp.data - xdp.data_meta; - - /* recalculate offset to account for any header - * adjustments and minus the metasize to copy the - * metadata in page_to_skb(). Note other cases do not - * build an skb and avoid using offset - */ - offset = xdp.data - page_address(xdp_page) - - vi->hdr_len - metasize; - - /* recalculate len if xdp.data, xdp.data_end or - * xdp.data_meta were adjusted - */ - len = xdp.data_end - xdp.data + vi->hdr_len + metasize; - - /* recalculate headroom if xdp.data or xdp_data_meta - * were adjusted, note that offset should always point - * to the start of the reserved bytes for virtio_net - * header which are followed by xdp.data, that means - * that offset is equal to the headroom (when buf is - * starting at the beginning of the page, otherwise - * there is a base offset inside the page) but it's used - * with a different starting point (buf start) than - * xdp.data (buf start + vnet hdr size). If xdp.data or - * data_meta were adjusted by the xdp prog then the - * headroom size has changed and so has the offset, we - * can use data_hard_start, which points at buf start + - * vnet hdr size, to calculate the new headroom and use - * it later to compute buf start in page_to_skb() - */ - headroom = xdp.data - xdp.data_hard_start - metasize; - - /* We can only create skb based on xdp_page. */ - if (unlikely(xdp_page != page)) { - rcu_read_unlock(); - put_page(page); - head_skb = page_to_skb(vi, rq, xdp_page, offset, - len, PAGE_SIZE); - return head_skb; - } - break; + head_skb = build_skb_from_xdp_buff(dev, vi, &xdp, xdp_frags_truesz); + rcu_read_unlock(); + return head_skb; case XDP_TX: stats->xdp_tx++; xdpf = xdp_convert_buff_to_frame(&xdp); if (unlikely(!xdpf)) { - if (unlikely(xdp_page != page)) - put_page(xdp_page); - goto err_xdp; + netdev_dbg(dev, "convert buff to frame failed for xdp\n"); + goto err_xdp_frags; } err = virtnet_xdp_xmit(dev, 1, &xdpf, 0); if (unlikely(!err)) { xdp_return_frame_rx_napi(xdpf); } else if (unlikely(err < 0)) { trace_xdp_exception(vi->dev, xdp_prog, act); - if (unlikely(xdp_page != page)) - put_page(xdp_page); - goto err_xdp; + goto err_xdp_frags; } *xdp_xmit |= VIRTIO_XDP_TX; if (unlikely(xdp_page != page)) @@ -1231,11 +1189,8 @@ static struct sk_buff *receive_mergeable(struct net_device *dev, case XDP_REDIRECT: stats->xdp_redirects++; err = xdp_do_redirect(dev, &xdp, xdp_prog); - if (err) { - if (unlikely(xdp_page != page)) - put_page(xdp_page); - goto err_xdp; - } + if (err) + goto err_xdp_frags; *xdp_xmit |= VIRTIO_XDP_REDIR; if (unlikely(xdp_page != page)) put_page(page); @@ -1248,9 +1203,7 @@ static struct sk_buff *receive_mergeable(struct net_device *dev, trace_xdp_exception(vi->dev, xdp_prog, act); fallthrough; case XDP_DROP: - if (unlikely(xdp_page != page)) - __free_pages(xdp_page, 0); - goto err_xdp; + goto err_xdp_frags; } err_xdp_frags: shinfo = xdp_get_shared_info_from_buff(&xdp);