From patchwork Wed Sep 17 20:49:41 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: 390551 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 4A369140180 for ; Thu, 18 Sep 2014 06:50:04 +1000 (EST) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1757029AbaIQUtt (ORCPT ); Wed, 17 Sep 2014 16:49:49 -0400 Received: from userp1040.oracle.com ([156.151.31.81]:41656 "EHLO userp1040.oracle.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1756433AbaIQUtp (ORCPT ); Wed, 17 Sep 2014 16:49:45 -0400 Received: from ucsinet22.oracle.com (ucsinet22.oracle.com [156.151.31.94]) by userp1040.oracle.com (Sentrion-MTA-4.3.2/Sentrion-MTA-4.3.2) with ESMTP id s8HKnivp001476 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-SHA bits=256 verify=OK); Wed, 17 Sep 2014 20:49:44 GMT Received: from aserz7021.oracle.com (aserz7021.oracle.com [141.146.126.230]) by ucsinet22.oracle.com (8.14.5+Sun/8.14.5) with ESMTP id s8HKnhBA006569 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-SHA bits=256 verify=NO); Wed, 17 Sep 2014 20:49:44 GMT Received: from abhmp0005.oracle.com (abhmp0005.oracle.com [141.146.116.11]) by aserz7021.oracle.com (8.14.4+Sun/8.14.4) with ESMTP id s8HKnhee018401; Wed, 17 Sep 2014 20:49:43 GMT Received: from [10.154.186.239] (/10.154.186.239) by default (Oracle Beehive Gateway v4.0) with ESMTP ; Wed, 17 Sep 2014 13:49:43 -0700 Message-ID: <5419F3E5.4050708@oracle.com> Date: Wed, 17 Sep 2014 16:49:41 -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: [PATCHv5 net-next 3/3] 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 5e64e60..3c4ee18 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 @@ -791,8 +798,36 @@ static int vnet_start_xmit(struct sk_buff *skb, struct net_device *dev) if (unlikely(!port)) 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);