From patchwork Thu Jul 1 01:17:28 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Vadim Fedorenko X-Patchwork-Id: 469445 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-18.8 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID, DKIM_VALID_AU, HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_CR_TRAILER, INCLUDES_PATCH, MAILING_LIST_MULTI, SPF_HELO_NONE, SPF_PASS, USER_AGENT_GIT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id CA48EC11F68 for ; Thu, 1 Jul 2021 01:17:43 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id ABC3B613CE for ; Thu, 1 Jul 2021 01:17:43 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S238371AbhGABUM (ORCPT ); Wed, 30 Jun 2021 21:20:12 -0400 Received: from novek.ru ([213.148.174.62]:59412 "EHLO novek.ru" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S238355AbhGABUL (ORCPT ); Wed, 30 Jun 2021 21:20:11 -0400 Received: from nat1.ooonet.ru (gw.zelenaya.net [91.207.137.40]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by novek.ru (Postfix) with ESMTPSA id 69DBC503D27; Thu, 1 Jul 2021 04:15:36 +0300 (MSK) DKIM-Filter: OpenDKIM Filter v2.11.0 novek.ru 69DBC503D27 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=novek.ru; s=mail; t=1625102137; bh=S/pmJ6v4x/O3zU446UUJOxVBua7REalDr39f/p7ljbI=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=JHYx3tcwcQMp/7DQV/4ueXjuRHylJyYKuCXqBbUhi1ISzVaXxZe9CDNOM13MNzpWA Cudjw3gmHNPFJZ5xHRFUsdxz8EghXc8AgiLs3Pv9OWFSGUzUAlQC5TUXz6US1TectF MqTSy0OD3Evvvf6C5JFeIQN1N7nWpg9QDZH5yQcc= From: Vadim Fedorenko To: David Ahern , netdev@vger.kernel.org Cc: Jakub Kicinski , Hideaki YOSHIFUJI , "David S. Miller" , Pablo Neira Ayuso , Florian Westphal , Vadim Fedorenko Subject: [RFC net-next 2/2] net: ipv4: Consolidate ipv4_mtu and ip_dst_mtu_maybe_forward Date: Thu, 1 Jul 2021 04:17:28 +0300 Message-Id: <20210701011728.22626-3-vfedorenko@novek.ru> X-Mailer: git-send-email 2.18.4 In-Reply-To: <20210701011728.22626-1-vfedorenko@novek.ru> References: <20210701011728.22626-1-vfedorenko@novek.ru> Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org Consolidate IPv4 MTU code the same way it is done in IPv6 to have code aligned in both address families Signed-off-by: Vadim Fedorenko --- include/net/ip.h | 22 ++++++++++++++++++---- net/ipv4/route.c | 21 +-------------------- 2 files changed, 19 insertions(+), 24 deletions(-) diff --git a/include/net/ip.h b/include/net/ip.h index d9683bef8684..ed261f2a40ac 100644 --- a/include/net/ip.h +++ b/include/net/ip.h @@ -436,18 +436,32 @@ static inline bool ip_sk_ignore_df(const struct sock *sk) static inline unsigned int ip_dst_mtu_maybe_forward(const struct dst_entry *dst, bool forwarding) { + const struct rtable *rt = (const struct rtable *)dst; struct net *net = dev_net(dst->dev); unsigned int mtu; if (net->ipv4.sysctl_ip_fwd_use_pmtu || ip_mtu_locked(dst) || - !forwarding) - return dst_mtu(dst); + !forwarding) { + mtu = rt->rt_pmtu; + if (mtu && time_before(jiffies, rt->dst.expires)) + goto out; + } /* 'forwarding = true' case should always honour route mtu */ mtu = dst_metric_raw(dst, RTAX_MTU); - if (!mtu) - mtu = min(READ_ONCE(dst->dev->mtu), IP_MAX_MTU); + if (mtu) + goto out; + + mtu = READ_ONCE(dst->dev->mtu); + + if (unlikely(ip_mtu_locked(dst))) { + if (rt->rt_uses_gateway && mtu > 576) + mtu = 576; + } + +out: + mtu = min_t(unsigned int, mtu, IP_MAX_MTU); return mtu - lwtunnel_headroom(dst->lwtstate, mtu); } diff --git a/net/ipv4/route.c b/net/ipv4/route.c index 99c06944501a..04754d55b3c1 100644 --- a/net/ipv4/route.c +++ b/net/ipv4/route.c @@ -1299,26 +1299,7 @@ static unsigned int ipv4_default_advmss(const struct dst_entry *dst) INDIRECT_CALLABLE_SCOPE unsigned int ipv4_mtu(const struct dst_entry *dst) { - const struct rtable *rt = (const struct rtable *)dst; - unsigned int mtu = rt->rt_pmtu; - - if (!mtu || time_after_eq(jiffies, rt->dst.expires)) - mtu = dst_metric_raw(dst, RTAX_MTU); - - if (mtu) - goto out; - - mtu = READ_ONCE(dst->dev->mtu); - - if (unlikely(ip_mtu_locked(dst))) { - if (rt->rt_uses_gateway && mtu > 576) - mtu = 576; - } - -out: - mtu = min_t(unsigned int, mtu, IP_MAX_MTU); - - return mtu - lwtunnel_headroom(dst->lwtstate, mtu); + return ip_dst_mtu_maybe_forward(dst, false); } EXPORT_INDIRECT_CALLABLE(ipv4_mtu);