From patchwork Fri Sep 12 23:19:39 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: 388826 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 376E41401AD for ; Sat, 13 Sep 2014 09:19:48 +1000 (EST) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751812AbaILXTo (ORCPT ); Fri, 12 Sep 2014 19:19:44 -0400 Received: from aserp1040.oracle.com ([141.146.126.69]:45225 "EHLO aserp1040.oracle.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751399AbaILXTn (ORCPT ); Fri, 12 Sep 2014 19:19:43 -0400 Received: from ucsinet21.oracle.com (ucsinet21.oracle.com [156.151.31.93]) by aserp1040.oracle.com (Sentrion-MTA-4.3.2/Sentrion-MTA-4.3.2) with ESMTP id s8CNJfJs005113 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-SHA bits=256 verify=OK); Fri, 12 Sep 2014 23:19:42 GMT Received: from aserz7022.oracle.com (aserz7022.oracle.com [141.146.126.231]) by ucsinet21.oracle.com (8.14.4+Sun/8.14.4) with ESMTP id s8CNJe4e022233 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-SHA bits=256 verify=NO); Fri, 12 Sep 2014 23:19:40 GMT Received: from abhmp0004.oracle.com (abhmp0004.oracle.com [141.146.116.10]) by aserz7022.oracle.com (8.14.4+Sun/8.14.4) with ESMTP id s8CNJdrO026600; Fri, 12 Sep 2014 23:19:39 GMT Received: from [10.154.147.184] (/10.154.147.184) by default (Oracle Beehive Gateway v4.0) with ESMTP ; Fri, 12 Sep 2014 16:19:39 -0700 Message-ID: <54137F8B.6060908@oracle.com> Date: Fri, 12 Sep 2014 19:19:39 -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 Subject: [PATCHv2 net-next 3/3] sunvnet: generate ICMP PTMUD messages for smaller port MTUs X-Source-IP: ucsinet21.oracle.com [156.151.31.93] 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 | 34 ++++++++++++++++++++++++++++++++++ 1 files changed, 34 insertions(+), 0 deletions(-) diff --git a/drivers/net/ethernet/sun/sunvnet.c b/drivers/net/ethernet/sun/sunvnet.c index b557ec4..b2381f0 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 @@ -752,6 +759,33 @@ static int vnet_start_xmit(struct sk_buff *skb, struct net_device *dev) goto out_dropped; if (skb->len > port->vio.rmtu) { + unsigned long localmtu = port->vio.rmtu - ETH_HLEN; + + if (port->vio.ver.major == 1 && port->vio.ver.minor >= 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; }