Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id ; Tue, 23 Jul 2002 04:24:08 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id ; Tue, 23 Jul 2002 04:24:07 -0400 Received: from mail12.svr.pol.co.uk ([195.92.193.215]:21008 "EHLO mail12.svr.pol.co.uk") by vger.kernel.org with ESMTP id ; Tue, 23 Jul 2002 04:24:06 -0400 Date: Tue, 23 Jul 2002 09:26:55 +0100 To: linux-kernel@vger.kernel.org Subject: Re: [2.6] Most likely to be merged by Halloween... THE LIST Message-ID: <20020723082655.GC1393@fib011235813.fsnet.co.uk> References: Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.4i From: Joe Thornber Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2492 Lines: 53 On Mon, Jul 22, 2002 at 01:31:11PM -0500, Ben Rafanello wrote: > I believe you are referring to Device Mapper, which could, in theory, > handle the AIX metadata layout. However, AFAIK, there are no tools > currently available or under development for Device Mapper to make > this happen. Currently, EVMS is the only way to read/write to AIX > volumes under Linux. This is absolutely correct, LVM2 does not currently support AIX metadata. However the LVM2 tools were designed to support multiple metadata formats, and it really would be very little work to write the code to do this (after all this is just a little bit of userland code, rather than kernel code in EVMS). ATM Sistina are not willing to pay for this work, so it will have to come from some other part of the community. > EVMS can snapshot anything it sees - partitions, LVM volumes, MD devices, > OS/2 volumes, AIX volumes, etc. LVM2 does do snapshots of LVM2 volumes, > but if it isn't an LVM volume, LVM2 can not snapshot it. Device Mapper, > however, could snapshot partitions and other non-LVM volumes if only the > tools were available. There is a little tool called dmsetup: http://people.sistina.com/~thornber/dmsetup_8.html that is essentially a very simple volume manager. But it does give you full access to all the facilities of device-mapper. eg, I just used it to create writeable snapshots of a CD, very useful for demonstrating distros. LVM2 will support physical volumes that it is not allowed to write metadata to very soon. > As for resizing partitions, EVMS has the code to > manipulate partition tables, including the resizing of partitions. There > does not appear to be anything in either LVM2 or Device Mapper for > manipulating partition tables and resizing partitions. There will never be partition manipulation code in LVM2, there are plenty of excellent tools for resizing partitions (eg, parted). We have better things to do than reinventing wheels. Personally I would remove the partition recognition code from the kernel completely, and setup partitions from userland using device-mapper. You need root permissions to read a partition table, *not* kernel perms. But somehow I can't see people going along with this plan :) - Joe - 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/