From mboxrd@z Thu Jan 1 00:00:00 1970 From: Tejun Heo Subject: Re: [patch ide-dev 8/9] make ide_task_ioctl() use REQ_DRIVE_TASKFILE Date: Tue, 01 Mar 2005 00:24:17 +0900 Message-ID: <422337A1.4060806@gmail.com> References: <20050227073608.GA30796@htj.dyndns.org> <200502271731.29448.bzolnier@elka.pw.edu.pl> Mime-Version: 1.0 Content-Type: text/plain; charset=iso-8859-1; format=flowed Content-Transfer-Encoding: 7bit Received: from wproxy.gmail.com ([64.233.184.195]:11342 "EHLO wproxy.gmail.com") by vger.kernel.org with ESMTP id S261645AbVB1PYr (ORCPT ); Mon, 28 Feb 2005 10:24:47 -0500 Received: by wproxy.gmail.com with SMTP id 68so936536wri for ; Mon, 28 Feb 2005 07:24:46 -0800 (PST) In-Reply-To: <200502271731.29448.bzolnier@elka.pw.edu.pl> Sender: linux-ide-owner@vger.kernel.org List-Id: linux-ide@vger.kernel.org To: Bartlomiej Zolnierkiewicz Cc: linux-ide@vger.kernel.org, linux-kernel@vger.kernel.org Hi, Bartlomiej Zolnierkiewicz wrote: > On Sunday 27 February 2005 08:36, Tejun Heo wrote: > >> Hello, Bartlomiej. >> >> This patch should be modified to use flagged taskfile if the >>task_end_request_fix patch isn't applied. As non-flagged taskfile >>won't return valid result registers, TASK ioctl users won't get the >>correct register output. > > > Nope, it works just fine because REQ_DRIVE_TASK used only > no-data protocol, please check task_no_data_intr(). > Sorry, I missed that. IDE really has a lot of ways to finish a command, doesn't it? hdio.txt is gonna look ugly. :-) > >> IMHO, this flag-to-get-result-registers thing is way too subtle. How >>about keeping old behavior by just not copying out register outputs in >>ide_taskfile_ioctl() in applicable cases instead of not reading >>registers when ending commands? That is, unless there's some >>noticeable performance impacts I'm not aware of. > > > This would miss whole point of not _reading_ these registers (IO is slow). > IMHO new flags denoting {in,out} registers should be added (to > to share them with libata) so new code can be sane and old flags would map > on new flags when needed. Please do it. Or, let me know what you have in mind (added fields, flag names, etc...); then, I'll do it. I think we also need to hear Jeff's opinion as things need to be added to ata.h. Thanks. -- tejun