From owner-cvs-all Mon Jan 27 1:53:59 2003 Delivered-To: cvs-all@freebsd.org Received: from mx1.FreeBSD.org (mx1.freebsd.org [216.136.204.125]) by hub.freebsd.org (Postfix) with ESMTP id 2C0F237B401; Mon, 27 Jan 2003 01:53:58 -0800 (PST) Received: from critter.freebsd.dk (critter.freebsd.dk [212.242.86.163]) by mx1.FreeBSD.org (Postfix) with ESMTP id 5250343E4A; Mon, 27 Jan 2003 01:53:57 -0800 (PST) (envelope-from phk@freebsd.org) Received: from critter.freebsd.dk (localhost [127.0.0.1]) by critter.freebsd.dk (8.12.6/8.12.6) with ESMTP id h0R9rtQl021121; Mon, 27 Jan 2003 10:53:55 +0100 (CET) (envelope-from phk@freebsd.org) To: Marcel Moolenaar Cc: Nate Lawson , cvs-committers@freebsd.org, cvs-all@freebsd.org Subject: Re: cvs commit: src/sbin/disklabel disklabel.c From: phk@freebsd.org In-Reply-To: Your message of "Mon, 27 Jan 2003 01:50:04 PST." <20030127095004.GA2876@dhcp01.pn.xcllnt.net> Date: Mon, 27 Jan 2003 10:53:55 +0100 Message-ID: <21120.1043661235@critter.freebsd.dk> Sender: owner-cvs-all@FreeBSD.ORG Precedence: bulk List-ID: List-Archive: (Web Archive) List-Help: (List Instructions) List-Subscribe: List-Unsubscribe: X-Loop: FreeBSD.ORG In message <20030127095004.GA2876@dhcp01.pn.xcllnt.net>, Marcel Moolenaar write s: >> As far as I know, GPT does not repeat BSD's mistake of putting the >> meta-data inside the partitions, so nothing prevents you from >> creating a (actually two: one for each copy) partitions which >> map to the area of the disk where the metadata is. > >Yes, GPT does prevent us from doing that because the GPT header >contains the first and last LBA of user storage that is managed >by the GPT and the GPT itself is not user storage and hence >cannot be included in the range. Since all partitions have to be >defined between the first and last LBA, it follows immediately >that GPT does not allow covering the GPT meta-data with partitions. I didn't mean you should create GPT partitions to cover them, that would be repeating the BSD label mistake. I simply meant that the geom_gpt.c class should create two providers which correspond to the applicable ranges of the consumer. Those two would show up in /dev as "ad0.gpt0" and "ad0.gpt1" or whatever you decide to call them, and you can open/read/write them as much as you like: no need for ioctls. -- Poul-Henning Kamp | UNIX since Zilog Zeus 3.20 phk@FreeBSD.ORG | TCP/IP since RFC 956 FreeBSD committer | BSD since 4.3-tahoe Never attribute to malice what can adequately be explained by incompetence. To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe cvs-all" in the body of the message