From mboxrd@z Thu Jan 1 00:00:00 1970 From: Stephen Hemminger Subject: Re: Proposed interface for per-packet mesh-ttl Date: Mon, 30 Jul 2007 21:53:16 +0100 Message-ID: <20070730215316.5c236e18@oldman> References: <445f43ac0707031149o2b50fc0en48aef4130b4b60ec@mail.gmail.com> <445f43ac0707031229m4ed60e0cg7960437c3e373c8e@mail.gmail.com> <20070727195616.GA31510@infradead.org> <1185574942.17934.9.camel@xo-13-A4-25.localdomain> <20070728073145.57155e03@oldman> <445f43ac0707301337l2f7d62ebx6955a12cd89c6bd3@mail.gmail.com> Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Cc: "Dan Williams" , "Christoph Hellwig" , netdev@vger.kernel.org To: "Javier Cardona" Return-path: Received: from smtp2.linux-foundation.org ([207.189.120.14]:54342 "EHLO smtp2.linux-foundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S933154AbXG3Ux0 (ORCPT ); Mon, 30 Jul 2007 16:53:26 -0400 In-Reply-To: <445f43ac0707301337l2f7d62ebx6955a12cd89c6bd3@mail.gmail.com> Sender: netdev-owner@vger.kernel.org List-Id: netdev.vger.kernel.org On Mon, 30 Jul 2007 13:37:20 -0700 "Javier Cardona" wrote: > Hi Stephen, > > On 7/27/07, Stephen Hemminger wrote: > > In this case perhaps you can have a table that maps skb->priority to > > mesh ttl? priorty can already by handled by existing setsockopt calls, > > and modified by netfilter and QoS managements. > > Thanks for the feedback. IMHO overloading the [SOL_SOCKET] > SO_PRIORITY sockoption for something as different as changing the > mesh-ttl is quite a stretch. But I admit that it meets the driver > requirements of "never add sockopt" and "not [ab]use netfilter hooks". > If that's acceptable to all, I'll modify the patch in that direction. > > Cheers, > > Javier Take it as idea not a proscription. You can use TC rules to rewrite the priority. It is kind of like how priority is being mapped to TOS already in softmac. Alternatively, the TTL can be set with sockopt, but it is a IP so it would need an IP ttl to mesh mapping. The fundamental thing is to try and avoid topology specific options bleeding all the way up the socket layer, especially since the network layer is involved and may need to multipath.