From mboxrd@z Thu Jan 1 00:00:00 1970 From: "J.E.J. Bottomley" Subject: Re: aic7xxx_biosparam Date: Sun, 17 Nov 2002 21:20:10 -0600 Sender: linux-scsi-owner@vger.kernel.org Message-ID: <200211180320.gAI3KBV16803@localhost.localdomain> References: Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Return-path: Received: (from root@localhost) by pogo.mtv1.steeleye.com (8.9.3/8.9.3) id TAA04879 for ; Sun, 17 Nov 2002 19:20:14 -0800 Received: from localhost.localdomain (sshppp-200.mtv1.steeleye.com [172.16.1.200]) by pogo.mtv1.steeleye.com (8.9.3/8.9.3) with ESMTP id TAA04790 for ; Sun, 17 Nov 2002 19:20:12 -0800 Received: from mulgrave (jejb@localhost) by localhost.localdomain (8.11.6/linuxconf) with ESMTP id gAI3KBV16803 for ; Sun, 17 Nov 2002 21:20:11 -0600 In-Reply-To: Message from Doug Ledford of "Sun, 17 Nov 2002 21:46:45 EST." <20021118024645.GB4608@redhat.com> List-Id: linux-scsi@vger.kernel.org To: Linux Scsi Mailing List dledford@redhat.com said: > Hmmm..should that be changed though? I hope not. If we implement BIG_GETGEO then I've made all the wrong decisions for biosparam: since it can pass back ints, the implementations should all be using sector_div and we should do the truncation in the GETGEO ioctl since we can use the same biosparam call for both ioctls. > I beg to differ. At least on the Adaptec stuff, it gets pissy if the > partition tables don't look sane (at least older BIOSes do, and those > cards are still in use, so that means I try and make them work). > Besides, when I make changes in this code, the effects are instantly > visible in fdisk (well, after a module reload), so it get's used > somewhere. The argument is that no user space tools rely on the cyls value, only the sectors and heads. They all use the GETGEO ioctl, but also get the blocksize of the device and divide this out by the sectors*heads to get the true cyls value. I know this is the wrong short term decision: you should never implement an interface wrongly because it causes exactly this type of confusion. I'm just betting on the C/H/S mess being sorted out soon....I hope. James