From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756096AbXGaJI0 (ORCPT ); Tue, 31 Jul 2007 05:08:26 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1752677AbXGaJIR (ORCPT ); Tue, 31 Jul 2007 05:08:17 -0400 Received: from ns1.suse.de ([195.135.220.2]:48764 "EHLO mx1.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751702AbXGaJIQ (ORCPT ); Tue, 31 Jul 2007 05:08:16 -0400 Date: Tue, 31 Jul 2007 11:08:15 +0200 From: Jan Blunck To: Theodore Tso , linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org, Bharata B Rao Subject: Re: [RFC 12/26] ext2 white-out support Message-ID: <20070731090815.GF5101@hasse.suse.de> References: <20070730161323.100048969@weierstrass.suse.de> <20070730161324.261652101@weierstrass.suse.de> <20070731034515.GD25876@thunk.org> <20070731074436.GE5101@hasse.suse.de> <20070731083223.GE5469@schatzie.adilger.int> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20070731083223.GE5469@schatzie.adilger.int> Organization: SUSE LINUX Products GmbH, GF Markus Rex, HRB 16746 (AG Nuernberg) User-Agent: Mutt/1.5.16 (2007-06-09) Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org On Tue, Jul 31, Andreas Dilger wrote: > On Jul 31, 2007 09:44 +0200, Jan Blunck wrote: > > Ok, this is pretty similar to the way I implemented this for tmpfs. The > > problem is that the union mount code is explicitly checking if the filesystem > > is supporting whiteout. I used to use a new filesystem flag (FS_WHITEOUT) for > > this but thought that disk filesystem like ext2/3/4 will have problem with > > that if you mount an old image. So I guess I still need a feature flag. > > You also need whiteout support for extents. This could be done with > unwritten extents potentially, or as I previously proposed (RFC) in > linux-ext4. Maybe. But this is about something totally different: a whiteout filetype, an existing file that when it is found make the VFS return -ENOENT. Cheers, Jan