From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S267871AbUHPSug (ORCPT ); Mon, 16 Aug 2004 14:50:36 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S267889AbUHPSuf (ORCPT ); Mon, 16 Aug 2004 14:50:35 -0400 Received: from rproxy.gmail.com ([64.233.170.206]:4467 "EHLO mproxy.gmail.com") by vger.kernel.org with ESMTP id S267871AbUHPStv (ORCPT ); Mon, 16 Aug 2004 14:49:51 -0400 Message-ID: <311601c904081611491c23207d@mail.gmail.com> Date: Mon, 16 Aug 2004 12:49:47 -0600 From: Eric Mudama Reply-To: Eric Mudama To: Alan Cox Subject: Re: Re: Any news on a higher performance sata_sil SIL_QUIRK_MOD15WRITE workaround? Cc: Clem Taylor , Jeff Garzik , Linux Kernel Mailing List In-Reply-To: <1092399186.24406.15.camel@localhost.localdomain> Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit References: <411AFD2C.5060701@comcast.net> <411B118B.4040802@pobox.com> <411C4130.4000303@comcast.net> <1092399186.24406.15.camel@localhost.localdomain> Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org I'm not sure about "affected" drives, but the issue as Jeff pointed out is that SI3112/3114 send write data to the host in non-multiples of 512 bytes, if the command exceeds 15 LBAs in size. Up to 15*512 bytes gives you a single FIS of 15*512, for anything larger they have an internal algorithm that is pretty easy to figure out with a bus trace. To work with drives that aren't capable of handling this, you can't issue writes > 15 LBAs to the drive, hence the blacklist/workaround. --eric