From mboxrd@z Thu Jan  1 00:00:00 1970
From: Nikita Danilov <nikita@clusterfs.com>
Subject: Re: silent semantic changes with reiser4
Date: Fri, 27 Aug 2004 01:33:52 +0400
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Cc: Dmitry Baryshkov <mitya@school.ioffe.ru>,
  Hans Reiser <reiser@namesys.com>, Andrew Morton <akpm@osdl.org>, hch@lst.de,
  linux-fsdevel@vger.kernel.org, linux-kernel <linux-kernel@vger.kernel.org>,
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To: Christophe Saout <christophe@saout.de>
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Christophe Saout writes:
 > Am Freitag, den 27.08.2004, 00:30 +0400 schrieb Dmitry Baryshkov:
 > 
 > > Another example: Can ext2/etx3/reiserfsv3/xfs be implemented as reiser4
 > > plugins? From Hans' words it seems so. If this is correct, then maybe
 > > reiser4 core should be updated to completely replace current VFS layer?
 > > Then it's a good point to create a branch (in old development model it
 > > would be 2.7, dunno for new :), replace VFS layer with reiser4 core, and
 > > rewrite all (or at least most used) FS as reiser4 plugins. Then
 > > everybody will be happy.
 > > 
 > > But this looks too good to be true. Perhaps I misunderstood Hans' words
 > > aboud 'new disk format', did I?
 > 
 > No. You can change the format the reiser4 storage tree is stored in. As
 > long as other filesystems don't use the same underlying storage tree
 > this is not possible.

Wrong, plugin is called just below entry point from the VFS to the
file-system back-end. It can use reiser4 tree, or any storage layer it
wants. Or none at all: think about pseudo-files like
foo/metas/uid---they are also implemnted by plugins.

Programmer dedicated enough can (besides programming Fortran in any
language), write reiser4 plugin for any file-system. I will leave
description of this activity to people with better command over English
language.

Nikita.

 >