From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S265805AbUHaR5E (ORCPT ); Tue, 31 Aug 2004 13:57:04 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S266115AbUHaR5D (ORCPT ); Tue, 31 Aug 2004 13:57:03 -0400 Received: from mx-out.forthnet.gr ([193.92.150.6]:27556 "EHLO mx-out-04.forthnet.gr") by vger.kernel.org with ESMTP id S265805AbUHaR4D (ORCPT ); Tue, 31 Aug 2004 13:56:03 -0400 From: V13 To: Hans Reiser Subject: Re: silent semantic changes in reiser4 (brief attempt to document the idea of what reiser4 wants to do with metafiles and why Date: Tue, 31 Aug 2004 20:55:55 +0300 User-Agent: KMail/1.7 Cc: Andrew Morton , Linux Kernel , Linus Torvalds , reiserfs-list@namesys.com References: <41323AD8.7040103@namesys.com> In-Reply-To: <41323AD8.7040103@namesys.com> MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Content-Disposition: inline Message-Id: <200408312055.56335.v13@priest.com> X-Spam-Flag: NO Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org On Sunday 29 August 2004 23:21, Hans Reiser wrote: > The Idea > > You should be able to access metadata about a file the same way you > access the file's data, but with a name based on the filename followed > by a name to select the metadata of interest. > > Examples: > > cat song_of_silence/metas/owner > cat song_of_silence/metas/permissions > cat 10 > song_of_silence/metas/mixer_defaults/volume > cat song_of_silence/metas/license Maybe I'm crazy but: You're talking about a major change in the way filesystems work if this is going to be used by other FSs too. If I understand this correctly it is a completely new thing and trying to do it by patching existing well-known 'primitives' may be wrong. AFAIK and AFAICS the metadata are not files or directories. You can look at them as files/dirs but they are not, just like a tar is not a directory. I believe that the correct thing to do (tm) is to add a new 'concept' named 'metadata' (which already exists). This way you'll have files, directories and metadata (or whatever you call them). So, each directory can have metadatas and files and each file can have metadatas. Then you have to provide some new methods of accessing them and not to use chdir() etc. (lets say chdir_meta() to enter the meta dir which will work for files too). After entering the 'metadir' you'll be able to use existing methods etc to access its 'files'. This approach doesn't mess with existing things and can be extended for other filesystems too. (Just a thought) <>