From mboxrd@z Thu Jan 1 00:00:00 1970 From: James Bottomley Subject: Re: Status of patch as168 (sysfs readonly max_sectors attribute) Date: 15 Jan 2004 14:42:35 -0500 Sender: linux-scsi-owner@vger.kernel.org Message-ID: <1074195756.1868.222.camel@mulgrave> References: Mime-Version: 1.0 Content-Type: text/plain Content-Transfer-Encoding: 7bit Return-path: Received: from stat1.steeleye.com ([65.114.3.130]:3519 "EHLO hancock.sc.steeleye.com") by vger.kernel.org with ESMTP id S261595AbUAOTmm (ORCPT ); Thu, 15 Jan 2004 14:42:42 -0500 In-Reply-To: List-Id: linux-scsi@vger.kernel.org To: Alan Stern Cc: Jeff Garzik , SCSI development list On Thu, 2004-01-15 at 14:30, Alan Stern wrote: > If I understand this, you would like to see the low-level drivers manage > these things for themselves by talking directly to the block layer, > without having to go through the intermediate SCSI layers. This would > imply that any sysfs interface to max_sectors would then be the > responsibility of the driver, since the block layer itself is much too > generic to permit users to fiddle with the settings. > > Correct? Well, no, not exactly. At issue are some of the SCSI template parameters which are copied to the host structure and then simply passed straight through to the block queue. If you look in scsi_alloc_queue, it simply passes through these queue parameters. It's pretty pointless to have SCSI do anything about them at all, so Jeff was saying we could just strip this out of the template and the drivers and have them call the relevant blk_queue_ parameter functions directly. James I personally think this would have to be done *before* any queue activity, so probably in slave_alloc rather than slave_configure (although there's no reason not to readjust in slave_configure). James