From mboxrd@z Thu Jan 1 00:00:00 1970 From: Ben Pfaff Subject: Re: [PATCH v2.51 1/5] ofp-actions: Allow Consistency checking of OF1.3+ VLAN actions after mpls_push Date: Wed, 4 Dec 2013 13:24:29 -0800 Message-ID: <20131204212429.GA11354@nicira.com> References: <1385005606-30130-1-git-send-email-horms@verge.net.au> <1385005606-30130-2-git-send-email-horms@verge.net.au> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Cc: dev@openvswitch.org, netdev@vger.kernel.org, Jesse Gross , Pravin B Shelar , Ravi K , Joe Stringer To: Simon Horman Return-path: Received: from na3sys009aog124.obsmtp.com ([74.125.149.151]:49256 "HELO na3sys009aog124.obsmtp.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with SMTP id S1753864Ab3LDVYh (ORCPT ); Wed, 4 Dec 2013 16:24:37 -0500 Received: by mail-qa0-f46.google.com with SMTP id f11so7014061qae.19 for ; Wed, 04 Dec 2013 13:24:35 -0800 (PST) Content-Disposition: inline In-Reply-To: <1385005606-30130-2-git-send-email-horms@verge.net.au> Sender: netdev-owner@vger.kernel.org List-ID: On Thu, Nov 21, 2013 at 12:46:42PM +0900, Simon Horman wrote: > The aim of this patch is to support provide infrastructure for verification > of VLAN actions after an mpls_push action for OpenFlow1.3. This supplements > existing support for verifying these actions for pre-OpenFlow1.3. > > In OpenFlow1.1 and 1.2 MPLS tags are pushed after any VLAN tags that > immediately follow the ethernet header. This is pre-OpenFlow1.3 tag > ordering. Open vSwitch also uses this ordering when supporting MPLS > actions via Nicira extensions to OpenFlow1.0. > > When using pre-OpenFlow1.3 tag ordering an MPLS push action does not > affect the VLANs of a packet. If VLAN tags are present immediately after > the ethernet header then they remain present there. > > In of OpenFlow1.3+ MPLS LSEs are pushed before any VLAN tags that > immediately follow the ethernet header. This is OpenFlow1.3+ tag > ordering. > > When using OpenFlow1.3+ tag ordering an MPLS push action affects the > VLANs of a packet as any VLAN tags previously present after the ethernet > header are moved to be immediately after the newly pushed MPLS LSE. Thus > for the purpose of action consistency checking a packet may be changed > from a VLAN packet to a non-VLAN packet. > > In this way the effective value of the VLAN TCI of a packet may differ > after an MPLS push depending on the OpenFlow version in use. > > This patch does not enable the logic described above. > Rather it is disabled in ofpacts_check__(). It should > be enabled when support for OpenFlow1.3+ tag order is added > and enabled. > > Signed-off-by: Simon Horman As far as I can tell this doesn't make sense, because where the MPLS tag goes is a property of the action that we know at the time we parse the push_mpls action. So why isn't this patch just the following? diff --git a/lib/ofp-actions.c b/lib/ofp-actions.c index a02f842..f444374 100644 --- a/lib/ofp-actions.c +++ b/lib/ofp-actions.c @@ -2071,6 +2071,9 @@ ofpact_check__(enum ofputil_protocol *usable_protocols, struct ofpact *a, * Thus nothing can be assumed about the network protocol. * Temporarily mark that we have no nw_proto. */ flow->nw_proto = 0; + if (ofpact_get_PUSH_MPLS(a)->position == OFPACT_MPLS_BEFORE_VLAN) { + flow->vlan_tci = 0; + } return 0; case OFPACT_POP_MPLS: