From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932344AbZDHGeF (ORCPT ); Wed, 8 Apr 2009 02:34:05 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1762325AbZDHGdr (ORCPT ); Wed, 8 Apr 2009 02:33:47 -0400 Received: from srv5.dvmed.net ([207.36.208.214]:54838 "EHLO mail.dvmed.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1760855AbZDHGdq (ORCPT ); Wed, 8 Apr 2009 02:33:46 -0400 Message-ID: <49DC4545.5020702@pobox.com> Date: Wed, 08 Apr 2009 02:33:41 -0400 From: Jeff Garzik User-Agent: Thunderbird 2.0.0.21 (X11/20090320) MIME-Version: 1.0 To: Sergei Shtylyov CC: linux-ide@vger.kernel.org, linux-kernel@vger.kernel.org, alan@lxorguk.ukuu.org.uk Subject: Re: [PATCH 2/2 resend] libata-sff: avoid byte swapping in ata_sff_data_xfer() References: <200902152230.38271.sshtylyov@ru.mvista.com> In-Reply-To: <200902152230.38271.sshtylyov@ru.mvista.com> Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit X-Spam-Score: -4.4 (----) X-Spam-Report: SpamAssassin version 3.2.5 on srv5.dvmed.net summary: Content analysis details: (-4.4 points, 5.0 required) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Sergei Shtylyov wrote: > Handling of the trailing byte in ata_sff_data_xfer() is suboptimal bacause: > > - it always initializes the padding buffer to 0 which is not really needed in > both the read and write cases; > > - it has to use memcpy() to transfer a single byte from/to the padding buffer; > > - it uses io{read|write}16() accessors which swap bytes on the big endian CPUs > and so have to additionally convert the data from/to the little endian format > instead of using io{read|write}16_rep() accessors which are not supposed to > change the byte ordering. > > Signed-off-by: Sergei Shtylyov applied