Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932250AbZDHPAs (ORCPT ); Wed, 8 Apr 2009 11:00:48 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1762412AbZDHO7y (ORCPT ); Wed, 8 Apr 2009 10:59:54 -0400 Received: from srv5.dvmed.net ([207.36.208.214]:42986 "EHLO mail.dvmed.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932142AbZDHO7w (ORCPT ); Wed, 8 Apr 2009 10:59:52 -0400 Message-ID: <49DCBBE2.4050506@garzik.org> Date: Wed, 08 Apr 2009 10:59:46 -0400 From: Jeff Garzik User-Agent: Thunderbird 2.0.0.21 (X11/20090320) MIME-Version: 1.0 To: Mark Lord CC: Matthew Wilcox , linux-ide@vger.kernel.org, linux-kernel@vger.kernel.org, jgarzik@redhat.com, David Woodhouse Subject: Re: [PATCH 4/5] ide: Add support for TRIM References: <1238683047-13588-1-git-send-email-willy@linux.intel.com> <1238683047-13588-2-git-send-email-willy@linux.intel.com> <1238683047-13588-3-git-send-email-willy@linux.intel.com> <1238683047-13588-4-git-send-email-willy@linux.intel.com> <49DCB5A5.7040100@rtr.ca> In-Reply-To: <49DCB5A5.7040100@rtr.ca> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit X-Spam-Score: -4.4 (----) X-Spam-Report: SpamAssassin version 3.2.5 on srv5.dvmed.net summary: Content analysis details: (-4.4 points, 5.0 required) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1150 Lines: 36 Mark Lord wrote: > Matthew Wilcox wrote: >> From: David Woodhouse >> >> Signed-off-by: David Woodhouse >> [modified to reduce amount of special casing needed for discard] >> Signed-off-by: Matthew Wilcox >> --- > .. >> + task->tf.command = ATA_CMD_DSM; >> + task->tf.feature = ATA_DSM_TRIM; >> + task->tf.hob_feature = 0x00; >> + task->tf.nsect = size / 512; >> + task->tf.hob_nsect = (size / 512) >> 8; > .. > > Matthew (or others), > > Could you perhaps explain what the purpose of the data portion > of this command is for? The draft ATA spec I have here has mangled > text in the description -- like it's missing a crucial sentence there. > > So it's not obvious exactly why this command even needs data to > be transfered. It's a list of LBA ranges, like the NV-cache stuff recently added. Jeff -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/