Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S264902AbUAJGGh (ORCPT ); Sat, 10 Jan 2004 01:06:37 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S264905AbUAJGGh (ORCPT ); Sat, 10 Jan 2004 01:06:37 -0500 Received: from wombat.indigo.net.au ([202.0.185.19]:32004 "EHLO wombat.indigo.net.au") by vger.kernel.org with ESMTP id S264902AbUAJGGf (ORCPT ); Sat, 10 Jan 2004 01:06:35 -0500 Date: Sat, 10 Jan 2004 14:05:37 +0800 (WST) From: Ian Kent X-X-Sender: To: Mike Waychison cc: "H. Peter Anvin" , autofs mailing list , Kernel Mailing List Subject: Re: [autofs] [RFC] Towards a Modern Autofs In-Reply-To: <3FFF1499.7030508@sun.com> Message-ID: MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII X-MailScanner: Found to be clean X-MailScanner-SpamCheck: not spam, SpamAssassin (score=-5.5, required 8, AWL, BAYES_10, EMAIL_ATTRIBUTION, IN_REP_TO, QUOTED_EMAIL_TEXT, REPLY_WITH_QUOTES, USER_AGENT_PINE) Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1817 Lines: 47 On Fri, 9 Jan 2004, Mike Waychison wrote: > > > >This may sound a little silly but it may be able to be done using > >stackable filesystem methods (aka. Zadok et. al.). I'm thinking of an > >autofs filesystem stacked on a host filesystem. The dentrys corresponding > >to mount points marked in some way and the mount occuring under it, on top > >of the host filesystem. Yes I know it sounds ugly but maybe it's not. > >Maybe it's actually quite simple. I can't give an opinion yet as I'm still > >thinking it through and haven't done any feasibility. However, this > >approach would lend itself to providing autofs filesystem transparency. A > >requirement as yet not discussed. > > > >Ian > > > > > > > Doing stackable filesystems is still an area of OS research. It turns > out to be a very hard problem to solve (if it's possible at all). > Although there are systems in the wild that appear to work, they are > usually sub-optimal because there remains alot of issues such as > maintaining coherent caches, as well as just staying coherent given that > one filesystem may be directly accessible while also accessed from > another overlayed filesystem. Yes I see that in what I've read. But I'm thinking of a very tightly controlled autofs layer controlled only by automount. Once owned by automount that part of the underlying fs could only be accessed via automount. The boundry cases obviously are a sensitive area. > > Not really something you'd want to waste alot of time on unless your > looking for a phd thesis. ;) A masters one day might be good. Ian - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/