From mboxrd@z Thu Jan 1 00:00:00 1970 From: "H. Peter Anvin" Subject: Re: Exporting which partitions to md-configure Date: Mon, 30 Jan 2006 18:05:16 -0800 Message-ID: <43DEC5DC.1030709@zytor.com> References: <43DEB4B8.5040607@zytor.com> <17374.47368.715991.422607@cse.unsw.edu.au> <43DEC095.2090507@zytor.com> <17374.50399.1898.458649@cse.unsw.edu.au> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <17374.50399.1898.458649@cse.unsw.edu.au> Sender: linux-raid-owner@vger.kernel.org To: Neil Brown Cc: klibc list , Linux Kernel Mailing List , linux-raid@vger.kernel.org List-Id: linux-raid.ids Neil Brown wrote: > > Well, grepping through fs/partitions/*.c, the 'flags' thing is set by > efi.c, msdos.c sgi.c sun.c > > Of these, efi compares something against PARTITION_LINUX_RAID_GUID, > and msdos.c, sgi.c and sun. compare something against > LINUX_RAID_PARTITION. > > The former would look like > e6d6d379-f507-44c2-a23c-238f2a3df928 > in sysfs (I think); > The latter would look like > fd > (I suspect). > > These are both easily recognisable with no real room for confusion. Well, if we're going to have a generic facility it should make sense across the board. If all we're doing is supporting legacy usage we might as well export a flag. I guess we could have a single entry with a string of the form "efi:e6d6d379-f507-44c2-a23c-238f2a3df928" or "msdos:fd" etc -- it really doesn't make any difference to me, but it seems cleaner to have two pieces of data in two different sysfs entries. > > And if other partition styles wanted to add support for raid auto > detect, tell them "no". It is perfectly possible and even preferable > to live without autodetect. We should support legacy usage (those > above) but should discourage any new usage. > Why is that, keeping in mind this will all be done in userspace? -hpa