From mboxrd@z Thu Jan 1 00:00:00 1970 From: Jeff Garzik Subject: Re: [PROPOSED] ata: Report 16/32bit PIO as best we can Date: Mon, 13 Apr 2009 12:57:55 -0400 Message-ID: <49E36F13.2010903@garzik.org> References: <20090409133221.18202.63779.stgit@t61.ukuu.org.uk> <49DDF1EB.2060200@rtr.ca> <20090409140857.578a9146@lxorguk.ukuu.org.uk> <49E36939.2050402@garzik.org> <20090413173921.0880e16a@lxorguk.ukuu.org.uk> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Return-path: Received: from srv5.dvmed.net ([207.36.208.214]:35930 "EHLO mail.dvmed.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751486AbZDMQ6A (ORCPT ); Mon, 13 Apr 2009 12:58:00 -0400 In-Reply-To: <20090413173921.0880e16a@lxorguk.ukuu.org.uk> Sender: linux-ide-owner@vger.kernel.org List-Id: linux-ide@vger.kernel.org To: Alan Cox Cc: Mark Lord , linux-ide@vger.kernel.org, LKML , gwendal@google.com Alan Cox wrote: > On Mon, 13 Apr 2009 12:32:57 -0400 > Jeff Garzik wrote: > >>> I'm not sure sysfs helps much anyway - you have to open the device file >>> and keep it open while accessing the sysfs nodes anyway (something huge >>> numbers of apps hopelessly fail to do so) >> FWIW... here is the sysfs work I referred to (in a message sent several >> days ago in this thread)... >> >> http://lwn.net/Articles/294608/ > > Which indeed shows the same problems. There is nothing to stop changes in > the rest of the topology from causing me to write to the sysfs at the > wrong moment and reconfigure/misconfigure a different object to the one > intended. The horse has already left the barn, on that one... Google's ata transport class is consistent with existing transport class work in the kernel. It is also consistent with recent admonitions in the osdblk thread, regarding the "one piece of data per sysfs file" rule. Personally I think a netlink-like approach to managing and controlling SAS and ATA would be better, but that's not what gets merged... Jeff