Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1759055AbXENUpw (ORCPT ); Mon, 14 May 2007 16:45:52 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1755507AbXENUpn (ORCPT ); Mon, 14 May 2007 16:45:43 -0400 Received: from mailer.gwdg.de ([134.76.10.26]:55777 "EHLO mailer.gwdg.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754581AbXENUpm (ORCPT ); Mon, 14 May 2007 16:45:42 -0400 Date: Mon, 14 May 2007 22:38:46 +0200 (MEST) From: Jan Engelhardt To: Bharata B Rao cc: linux-kernel@vger.kernel.org, linux-fsdevel@vger.kernel.org, Jan Blunck Subject: Re: [RFC][PATCH 2/14] Add a new mount flag (MNT_UNION) for union mount In-Reply-To: <20070514093902.GD4139@in.ibm.com> Message-ID: References: <20070514093722.GB4139@in.ibm.com> <20070514093902.GD4139@in.ibm.com> MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII X-Spam-Report: Content analysis: 0.0 points, 6.0 required _SUMMARY_ Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1114 Lines: 35 On May 14 2007 15:09, Bharata B Rao wrote: > >Introduce MNT_UNION, MS_UNION and FS_WHT flags. There are the necessary flags >for doing > > mount /dev/hda3 /mnt -o union > >You need additional patches for util-linux for that to work. > >Signed-off-by: Jan Blunck >Signed-off-by: Bharata B Rao >--- > >+ /* Unions couldn't be writable if the filesystem >+ * doesn't know about whiteouts */ >+ err = -ENOTSUPP; >+ if ((mnt_flags & MNT_UNION) && >+ !(newmnt->mnt_sb->s_flags & MS_RDONLY) && >+ !(newmnt->mnt_sb->s_type->fs_flags & FS_WHT)) >+ goto unlock; >+ Maybe I am too biased towards unionfs/aufs, but if I have an {rw,rw} union with whiteouts disabled (delete=all in unionfs speak), then FS_WHT does not need to be supported. Your patches do not seem to do delete=all semantics, do they? Jan -- - 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/