From mboxrd@z Thu Jan 1 00:00:00 1970 From: Josef Sipek Subject: Re: [PATCH 01/24] Unionfs: Documentation Date: Tue, 9 Jan 2007 05:43:33 -0500 Message-ID: <20070109104333.GC25438@filer.fsl.cs.sunysb.edu> References: <20070108140224.3a814b7d.akpm@osdl.org> <200701090003.l0903Z2O017720@agora.fsl.cs.sunysb.edu> <20070109095345.GB12406@infradead.org> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Return-path: Received: from filer.fsl.cs.sunysb.edu ([130.245.126.2]:42299 "EHLO filer.fsl.cs.sunysb.edu" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751314AbXAIKp5 (ORCPT ); Tue, 9 Jan 2007 05:45:57 -0500 To: Christoph Hellwig , Erez Zadok , Andrew Morton , Shaya Potter , "Josef 'Jeff' Sipek" , linux-kernel@vger.kernel.org, linux-fsdevel@vger.kernel.org, viro@ftp.linux.org.uk, torvalds@osdl.org, mhalcrow@us.ibm.com, David Quigley Content-Disposition: inline In-Reply-To: <20070109095345.GB12406@infradead.org> Sender: linux-fsdevel-owner@vger.kernel.org List-Id: linux-fsdevel.vger.kernel.org On Tue, Jan 09, 2007 at 09:53:45AM +0000, Christoph Hellwig wrote: > On Mon, Jan 08, 2007 at 07:03:35PM -0500, Erez Zadok wrote: > > However, I must caution that a file system like ecryptfs is very different > > from Unionfs, the latter being a fan-out file system---and both have very > > different goals. The common code between the two file systems, at this > > stage, is not much (and we've already extracted some of it into the "stackfs > > layer"). > > I think that's an very important point. We have a chance to get that > non-fanout filesystems right quite easily - something I wished that would > have been done before the ecryptfs merge - while getting fan-out stackable > filesystems is a really hard task. Hard or harder? > In addition to that I know exactly > one fan-out stackable filesystem that is posisbly useful, which is unionfs. RAIF is another fan-out stackable fs with much more complex logic. (Just the other day, I saw an announcement for a new version on fsdevel.) Josef "Jeff" Sipek. -- Evolution, n.: A hypothetical process whereby infinitely improbable events occur with alarming frequency, order arises from chaos, and no one is given credit.