From patchwork Mon Sep 29 23:48:24 2014 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: David L Stevens X-Patchwork-Id: 394672 X-Patchwork-Delegate: davem@davemloft.net Return-Path: X-Original-To: patchwork-incoming@ozlabs.org Delivered-To: patchwork-incoming@ozlabs.org Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by ozlabs.org (Postfix) with ESMTP id 1FFB214010C for ; Tue, 30 Sep 2014 09:47:52 +1000 (EST) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755185AbaI2Xrs (ORCPT ); Mon, 29 Sep 2014 19:47:48 -0400 Received: from aserp1040.oracle.com ([141.146.126.69]:34380 "EHLO aserp1040.oracle.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753950AbaI2Xrr (ORCPT ); Mon, 29 Sep 2014 19:47:47 -0400 Received: from ucsinet22.oracle.com (ucsinet22.oracle.com [156.151.31.94]) by aserp1040.oracle.com (Sentrion-MTA-4.3.2/Sentrion-MTA-4.3.2) with ESMTP id s8TNlimH015890 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-SHA bits=256 verify=OK); Mon, 29 Sep 2014 23:47:45 GMT Received: from userz7021.oracle.com (userz7021.oracle.com [156.151.31.85]) by ucsinet22.oracle.com (8.14.5+Sun/8.14.5) with ESMTP id s8TNlhQh016499 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-SHA bits=256 verify=FAIL); Mon, 29 Sep 2014 23:47:44 GMT Received: from abhmp0008.oracle.com (abhmp0008.oracle.com [141.146.116.14]) by userz7021.oracle.com (8.14.4+Sun/8.14.4) with ESMTP id s8TNlhad013516; Mon, 29 Sep 2014 23:47:43 GMT Received: from [10.154.111.250] (/10.154.111.250) by default (Oracle Beehive Gateway v4.0) with ESMTP ; Mon, 29 Sep 2014 16:47:43 -0700 Message-ID: <5429EFC8.9080107@oracle.com> Date: Mon, 29 Sep 2014 19:48:24 -0400 From: David L Stevens Organization: Oracle Corporation User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:24.0) Gecko/20100101 Thunderbird/24.7.0 MIME-Version: 1.0 To: David Miller CC: netdev@vger.kernel.org, Sowmini Varadhan , Raghuram Kothahota Subject: [PATCHv9 net-next 4/4] sunvnet: generate ICMP PTMUD messages for smaller port MTUs X-Source-IP: ucsinet22.oracle.com [156.151.31.94] Sender: netdev-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org This patch sends ICMP and ICMPv6 messages for Path MTU Discovery when a remote port MTU is smaller than the device MTU. This allows mixing newer VIO protocol devices that support MTU negotiation with older devices that do not on the same vswitch. It also allows Linux-Linux LDOMs to use 64K-1 data packets even though Solaris vswitch is limited to <16K MTU. Signed-off-by: David L Stevens --- drivers/net/ethernet/sun/sunvnet.c | 37 +++++++++++++++++++++++++++++++++++- 1 files changed, 36 insertions(+), 1 deletions(-) diff --git a/drivers/net/ethernet/sun/sunvnet.c b/drivers/net/ethernet/sun/sunvnet.c index 3980471..1262697 100644 --- a/drivers/net/ethernet/sun/sunvnet.c +++ b/drivers/net/ethernet/sun/sunvnet.c @@ -17,6 +17,13 @@ #include #include +#if IS_ENABLED(CONFIG_IPV6) +#include +#endif + +#include +#include + #include #include @@ -913,8 +920,36 @@ static int vnet_start_xmit(struct sk_buff *skb, struct net_device *dev) if (unlikely(!skb)) goto out_dropped; - if (skb->len > port->rmtu) + if (skb->len > port->rmtu) { + unsigned long localmtu = port->rmtu - ETH_HLEN; + + if (vio_version_after_eq(&port->vio, 1, 3)) + localmtu -= VLAN_HLEN; + + if (skb->protocol == htons(ETH_P_IP)) { + struct flowi4 fl4; + struct rtable *rt = NULL; + + memset(&fl4, 0, sizeof(fl4)); + fl4.flowi4_oif = dev->ifindex; + fl4.flowi4_tos = RT_TOS(ip_hdr(skb)->tos); + fl4.daddr = ip_hdr(skb)->daddr; + fl4.saddr = ip_hdr(skb)->saddr; + + rt = ip_route_output_key(dev_net(dev), &fl4); + if (!IS_ERR(rt)) { + skb_dst_set(skb, &rt->dst); + icmp_send(skb, ICMP_DEST_UNREACH, + ICMP_FRAG_NEEDED, + htonl(localmtu)); + } + } +#if IS_ENABLED(CONFIG_IPV6) + else if (skb->protocol == htons(ETH_P_IPV6)) + icmpv6_send(skb, ICMPV6_PKT_TOOBIG, 0, localmtu); +#endif goto out_dropped; + } spin_lock_irqsave(&port->vio.lock, flags);