From mboxrd@z Thu Jan 1 00:00:00 1970 From: Jeff Garzik Subject: Re: [PATCH 2.6.20-rc3] fix broken retval test in sr_block_ioctl Date: Tue, 02 Jan 2007 17:37:37 -0500 Message-ID: <459ADEB1.7080505@pobox.com> References: <200701021724.39613.liml@rtr.ca> <200701021730.07356.liml@rtr.ca> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Return-path: Received: from srv5.dvmed.net ([207.36.208.214]:47373 "EHLO mail.dvmed.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S965011AbXABWhl (ORCPT ); Tue, 2 Jan 2007 17:37:41 -0500 In-Reply-To: <200701021730.07356.liml@rtr.ca> Sender: linux-ide-owner@vger.kernel.org List-Id: linux-ide@vger.kernel.org To: Mark Lord Cc: Tejun Heo , IDE/ATA development list , Andrew Morton , Douglas Gilbert Mark Lord wrote: > This patch adds support for passing ATA_12 and ATA_16 commands > through to ATAPI devices in libata. In practice, the upper layers will > still currently prevent ATA_16 commands, as no (?) ATAPI drives support > them yet. But it will work if such a drive is ever encountered. > > This patch is necessary for using SG_IO from userspace, > and an upcoming hdparm release will be updated to use this interface. > > Signed-off-by: Mark Lord > --- > Allow ATA_12 / ATA_16 passthru commands to be issued for ATAPI devices Douglas Gilbert noticed this a while ago. The patch's technical content is fine, but there is an open policy question: For some devices, there is an opcode overlap (BLANK? Doug probably remembers the issue better than I). And from a practical standpoint, to handle any vendor weird-isms (nahhh those never happen in ATAPI), it would be nice to be able to force the current (pre-mlord patch) behavior to ensure that all opcodes are passed to ATAPI. Absent a better idea, I would simply suggest adding a module parameter that restores the "all opcodes are passed to device, guaranteed" mode. I'm fine with changing the default behavior to that which is presented by your patch. Jeff