From patchwork Tue Jan 3 06:40:05 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Heng Qi X-Patchwork-Id: 13087212 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 96922C5479D for ; Tue, 3 Jan 2023 06:40:24 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S236695AbjACGkW (ORCPT ); Tue, 3 Jan 2023 01:40:22 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:59656 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230254AbjACGkV (ORCPT ); Tue, 3 Jan 2023 01:40:21 -0500 Received: from out30-7.freemail.mail.aliyun.com (out30-7.freemail.mail.aliyun.com [115.124.30.7]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id C7D8C1088; Mon, 2 Jan 2023 22:40:19 -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=ay29a033018046059;MF=hengqi@linux.alibaba.com;NM=1;PH=DS;RN=12;SR=0;TI=SMTPD_---0VYj.ouq_1672728015; Received: from localhost(mailfrom:hengqi@linux.alibaba.com fp:SMTPD_---0VYj.ouq_1672728015) by smtp.aliyun-inc.com; Tue, 03 Jan 2023 14:40:16 +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 v3 2/9] virtio-net: set up xdp for multi buffer packets Date: Tue, 3 Jan 2023 14:40:05 +0800 Message-Id: <20230103064012.108029-3-hengqi@linux.alibaba.com> X-Mailer: git-send-email 2.19.1.6.gb485710b In-Reply-To: <20230103064012.108029-1-hengqi@linux.alibaba.com> References: <20230103064012.108029-1-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 When the xdp program sets xdp.frags, which means it can process multi-buffer packets over larger MTU, so we continue to support xdp. But for single-buffer xdp, we should keep checking for MTU. Signed-off-by: Heng Qi Reviewed-by: Xuan Zhuo Acked-by: Jason Wang --- drivers/net/virtio_net.c | 10 ++++++---- 1 file changed, 6 insertions(+), 4 deletions(-) diff --git a/drivers/net/virtio_net.c b/drivers/net/virtio_net.c index 443aa7b8f0ad..60e199811212 100644 --- a/drivers/net/virtio_net.c +++ b/drivers/net/virtio_net.c @@ -3074,7 +3074,9 @@ static int virtnet_restore_guest_offloads(struct virtnet_info *vi) static int virtnet_xdp_set(struct net_device *dev, struct bpf_prog *prog, struct netlink_ext_ack *extack) { - unsigned long int max_sz = PAGE_SIZE - sizeof(struct padded_vnet_hdr); + unsigned int room = SKB_DATA_ALIGN(VIRTIO_XDP_HEADROOM + + sizeof(struct skb_shared_info)); + unsigned int max_sz = PAGE_SIZE - room - ETH_HLEN; struct virtnet_info *vi = netdev_priv(dev); struct bpf_prog *old_prog; u16 xdp_qp = 0, curr_qp; @@ -3095,9 +3097,9 @@ static int virtnet_xdp_set(struct net_device *dev, struct bpf_prog *prog, return -EINVAL; } - if (dev->mtu > max_sz) { - NL_SET_ERR_MSG_MOD(extack, "MTU too large to enable XDP"); - netdev_warn(dev, "XDP requires MTU less than %lu\n", max_sz); + if (prog && !prog->aux->xdp_has_frags && dev->mtu > max_sz) { + NL_SET_ERR_MSG_MOD(extack, "MTU too large to enable XDP without frags"); + netdev_warn(dev, "single-buffer XDP requires MTU less than %u\n", max_sz); return -EINVAL; }