From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753907AbYLONzl (ORCPT ); Mon, 15 Dec 2008 08:55:41 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1752821AbYLONzd (ORCPT ); Mon, 15 Dec 2008 08:55:33 -0500 Received: from mail-ew0-f17.google.com ([209.85.219.17]:36459 "EHLO mail-ew0-f17.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752269AbYLONzc (ORCPT ); Mon, 15 Dec 2008 08:55:32 -0500 DomainKey-Signature: a=rsa-sha1; c=nofws; d=gmail.com; s=gamma; h=message-id:date:from:reply-to:to:subject:in-reply-to:mime-version :content-type:content-transfer-encoding:content-disposition :references; b=NPhdLUmZzohjsNzTHDagSk/PiuJpVPH+tCjFJITHhh+n1c7xzZdJUqp+Nhl1i872kw Wlwd0A8bye4W6u3A+G2ZZV56QGW60nbDIFpHhMGezQfZSCQJT73Tvcl/e+S5VocTw29W dk8oMPi9U4RGxXNW8VJI6n+cnHZLxi4M0zcbA= Message-ID: <14cd75110812150555m36e1fef8w8f966b9acdd336@mail.gmail.com> Date: Mon, 15 Dec 2008 18:55:31 +0500 From: "Muhammad Mutahir Latif" Reply-To: mutahirlatif@gmail.com To: linux-kernel@vger.kernel.org Subject: Re: SATA passthrough commands from User Space In-Reply-To: <4940CFB3.8030005@garzik.org> MIME-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Content-Disposition: inline References: <14cd75110812110005n2809dae7n909a606f68ff1a61@mail.gmail.com> <4940CFB3.8030005@garzik.org> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Thank you Jeff for the SG_IO suggestion. Are there any numbers as to the average throughput achieved using the SG_IO ioctl. The reason I am asking is that for our scenario the data transfer throughput required might not be fulfilled using the SG_IO ioctl due to the SCSI->ATA translations. In case the SG_IO does not fulfill the requirement, where should we add IOCTL functionality. At first I was thinking of adding it to the AHCI driver, but by looking at the code I saw that the ahci driver only implements functions so that they can be hooked with the libata framework, so should I add IOCTL hooks to the libata?. Please let me know if I am by any chance going completely in the wrong direction. Thanks Mutahir On Thu, Dec 11, 2008 at 1:30 PM, Jeff Garzik wrote: > Muhammad Mutahir Latif wrote: >> >> Hi >> >> I am new to linux kernel development and need help in developing an >> application in linux for a SATA device. What is required is that the >> application needs to send raw SATA commands along with data (like Read >> DMA, Write FPDMA etc) to a SATA hard disk. Secondly we also have to >> achieve a reasonably high data transfer throughput. > > Use the existing SG_IO ioctl. > > Jeff > > > >