From mboxrd@z Thu Jan 1 00:00:00 1970 From: Brian King Subject: Re: [PATCH 1/2] scsi: Add scsi_device max_cmd_len (resend) Date: Fri, 28 Apr 2006 13:19:42 -0500 Message-ID: <44525CBE.1030409@us.ibm.com> References: <200604172240.k3HMes2V010154@d01av01.pok.ibm.com> <44522672.5010607@us.ibm.com> <1146237433.5251.7.camel@mulgrave.il.steeleye.com> Reply-To: brking@us.ibm.com Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Return-path: Received: from e3.ny.us.ibm.com ([32.97.182.143]:13450 "EHLO e3.ny.us.ibm.com") by vger.kernel.org with ESMTP id S1751792AbWD1STq (ORCPT ); Fri, 28 Apr 2006 14:19:46 -0400 In-Reply-To: <1146237433.5251.7.camel@mulgrave.il.steeleye.com> Sender: linux-ide-owner@vger.kernel.org List-Id: linux-ide@vger.kernel.org To: James Bottomley Cc: linux-scsi@vger.kernel.org, jgarzik@pobox.com, linux-ide@vger.kernel.org James Bottomley wrote: > On Fri, 2006-04-28 at 09:28 -0500, Brian King wrote: >> Any comments on the patch below? > > The mechanistic comment is that the max_cmd_len parameter should be per > target not per device. I don't have a problem with that. It could go in the target as well. > However, since this is SATA only, and SATA is supposed to be moving out > of the SCSI subsystem, I'm a bit loath to add things we'll have to > attempt to extract later. What would be the consequence of simply > lowering the host max_cmd_len by the result returned from IDENTIFY? That is what is done today, which works fine if you only have one device per host, but when you have multiple devices per host, there is no *good* value to put in the host max_cmd_len, hence the patch. This could also be completely contained in libata as my previous post suggests, if Jeff is OK with that. Brian -- Brian King eServer Storage I/O IBM Linux Technology Center