From owner-freebsd-stable@FreeBSD.ORG Wed Feb 16 15:58:17 2005 Return-Path: Delivered-To: freebsd-stable@freebsd.org Received: from mx1.FreeBSD.org (mx1.freebsd.org [216.136.204.125]) by hub.freebsd.org (Postfix) with ESMTP id 45CA216A4CE; Wed, 16 Feb 2005 15:58:17 +0000 (GMT) Received: from harmony.village.org (rover.village.org [168.103.84.182]) by mx1.FreeBSD.org (Postfix) with ESMTP id AD01343D48; Wed, 16 Feb 2005 15:58:16 +0000 (GMT) (envelope-from imp@bsdimp.com) Received: from localhost (warner@rover2.village.org [10.0.0.1]) by harmony.village.org (8.13.1/8.13.1) with ESMTP id j1GFtHv9071869; Wed, 16 Feb 2005 08:55:17 -0700 (MST) (envelope-from imp@bsdimp.com) Date: Wed, 16 Feb 2005 08:55:34 -0700 (MST) Message-Id: <20050216.085534.128329712.imp@bsdimp.com> To: nyan@jp.FreeBSD.org From: "M. Warner Losh" In-Reply-To: <20050216.131604.41667980.nyan@jp.FreeBSD.org> References: <20050215.210805.41634669.nyan@jp.FreeBSD.org> <20050215.135815.112575021.imp@bsdimp.com> <20050216.131604.41667980.nyan@jp.FreeBSD.org> X-Mailer: Mew version 3.3 on Emacs 21.3 / Mule 5.0 (SAKAKI) Mime-Version: 1.0 Content-Type: Text/Plain; charset=us-ascii Content-Transfer-Encoding: 7bit cc: freebsd-stable@freebsd.org cc: freebsd-current@freebsd.org cc: nakaji@jp.FreeBSD.org cc: wnabe@par.odn.ne.jp cc: sos@DeepCore.dk Subject: Re: UPDATE: ATA mkIII first official patches - please test! X-BeenThere: freebsd-stable@freebsd.org X-Mailman-Version: 2.1.1 Precedence: list List-Id: Production branch of FreeBSD source code List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Wed, 16 Feb 2005 15:58:17 -0000 In message: <20050216.131604.41667980.nyan@jp.FreeBSD.org> Takahashi Yoshihiro writes: : In article <20050215.135815.112575021.imp@bsdimp.com> : Warner Losh writes: : : > > The following is the result when use SATA 200GB disk on pc98. It is : > > clearly that recognizing a geometry fails. : > > : > > atapci0: port 0xc000-0xc00f,0x602c-0x602f,0x6030-0x6037,0x6028-0x602b,0x6020-0x6027 mem 0x20411000-0x204113ff irq 10 at device 17.0 on pci0 : > > ad4: ATA-6 disk at ata2-master : > > ad4: 190782MB (390721968 sectors), 387621 C, 16 H, 63 S, 512 B : > > ad4: 16 secs/int, 1 depth queue, SATA150 : > > : > > BIOS Geometries: : > > 1:1778ffff 0..6008=6009 cylinders, 0..255=256 heads, 1..255=255 sectors : > : > Is this the geometry that the PC98 BIOS uses? : : Yes. I see. Let me see if I understand the implications: (1) This disk won't interoperate with other OSes on the pc98 machine because the pc98 partition format specifies things in terms of CHS, but doesn't specify an actual geometry. (2) Further, since dp_scyl and dp_ecyl are both 16bits, we are limited to 65535 cylinders. The above geometry of 387621 violates this assumption. So you can really only use 66059280 of the 390721968 sectors on this disk (or about 17%). (3) It is insufficent to fix this in geom_pc98 because that is not used until after the partition is placed on the disk and fdisk_pc98 needs the geometry to place that partition. (4) This only impacts newer ATA6 disks. ATA5 and older appear to be working properly. ata6 disks need some other mechanism to get this information, correct? When I asked about the 'get the geometry from the BIOS' patches that are circulating, I was told that it was hard to match the FreeBSD device to the BIOS table. Do I understand things correctly? Warner