From mboxrd@z Thu Jan 1 00:00:00 1970 From: Mark Lord Subject: Re: [PATCH] libata: increase LBA48 max sectors to 65535 Date: Wed, 15 Feb 2006 18:05:50 -0500 Message-ID: <43F3B3CE.5060105@pobox.com> References: <1139754779159-git-send-email-htejun@gmail.com> <43EF8E61.5040409@pobox.com> <43EFD73D.4070207@gmail.com> <43F011DF.6020203@pobox.com> <20060215072449.GA31691@htj.dyndns.org> <20060215130725.GP4203@suse.de> <43F342E6.9060909@gmail.com> <20060215151200.GW4203@suse.de> <43F38D49.4080601@pobox.com> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Return-path: Received: from mx2.magma.ca ([206.191.0.250]:35716 "EHLO mx2.magma.ca") by vger.kernel.org with ESMTP id S1751156AbWBOXHO (ORCPT ); Wed, 15 Feb 2006 18:07:14 -0500 In-Reply-To: <43F38D49.4080601@pobox.com> Sender: linux-ide-owner@vger.kernel.org List-Id: linux-ide@vger.kernel.org To: Jeff Garzik Cc: Jens Axboe , Tejun Heo , albertcc@tw.ibm.com, linux-ide@vger.kernel.org Jeff Garzik wrote: > Jens Axboe wrote: >> On Thu, Feb 16 2006, Tejun Heo wrote: >> >>> Jens Axboe wrote: >>> >>>> On Wed, Feb 15 2006, Tejun Heo wrote: >>>> >>>> >>>>> max_hw_sectors/max_sectors separation patch made into the tree, >>>>> increase max_sectors to its hardware limit. .. > Its set to 200 for a libata-related reason that I now forget :( > > It had nothing to do with controllers or devices, hence the FIXME. > > As an aside, I wonder if the PRD limit is unnecessarily low. I don't > remember seeing anything that claimed we were limited to 256 s/g entries > in the old IDE docs? > > Jeff Well, originally I wrote ide-dma.c with a 256 PRD limit, because that corresponds to the absolute worst case of only one sector per PRD. The pre-LBA48 protocol cannot read/write more than that with a single command. But nowadays.. Cheers -- Mark Lord Real-Time Remedies Inc. mlord@pobox.com