From mboxrd@z Thu Jan 1 00:00:00 1970 From: Stephen Hemminger Subject: Re: [patch] d80211: use pfifo_qdisc_ops rather thand80211-specific qdisc Date: Thu, 2 Nov 2006 14:34:21 -0800 Message-ID: <20061102143421.1f6c8ba3@freekitty> References: <1162485837.16971.5.camel@johannes.berg> Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Cc: Simon Barber , Christoph Hellwig , James Ketrenos , "John W. Linville" , Jeff Garzik , Patrick McHardy , David Kimdon , netdev@vger.kernel.org Return-path: Received: from smtp.osdl.org ([65.172.181.4]:36815 "EHLO smtp.osdl.org") by vger.kernel.org with ESMTP id S1751429AbWKBWjm (ORCPT ); Thu, 2 Nov 2006 17:39:42 -0500 To: Johannes Berg In-Reply-To: <1162485837.16971.5.camel@johannes.berg> Sender: netdev-owner@vger.kernel.org List-Id: netdev.vger.kernel.org On Thu, 02 Nov 2006 17:43:57 +0100 Johannes Berg wrote: > On Thu, 2006-11-02 at 08:33 -0800, Simon Barber wrote: > > There are many reasons to have the master device - and many reasons not > > to get rid of it. The only excpetion is when using a limited fullmac > > card. Some fullmac cards only support a single ethernet interface, so > > for these cards a single device may be OK, if we want to allow multiple > > different appearences for different types of card (a bad thing in my > > book). (Note - older prism 54g fullmac cards support WDS, hence need > > multiple interfaces). > > > > The master interface represents the physical networking device that > > works using native 802.11 frames. The qdisc works on 802.11 frames - not > > ethernet, and it can change how 802.11 management frames are queued. It > > can only be got rid of in the case of a fullmac card with only a single > > interface, where all management frames are processed in the card. > > > > In addition as we move to make 802.11 devices native (i.e. create an > > 802.11 protocol) the 802.11 master interface will be essential. > > While these are good points, I don't believe having the master interface > as a *netdev* is essential. In fact, it now has no functionality as a > netdev, if you try routing packets over it they're simply dropped. It makes 802.11 packet capture easier as well. Please don't invent yet another network access object for the master device. > Of course we need some notion of the wireless PHY and cfg80211 > explicitly represents that by assigning a wiphy index, but there's no > need for it to be a netdev. > > johannes -- Stephen Hemminger