From mboxrd@z Thu Jan 1 00:00:00 1970 From: Aboo Valappil Subject: About SG Elements of request_buffer Date: Sun, 15 Oct 2006 22:03:54 +1000 Message-ID: <453223AA.50409@aboo.org> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Return-path: Received: from ppp245-155.static.internode.on.net ([59.167.245.155]:30380 "EHLO localhost.localdomain") by vger.kernel.org with ESMTP id S1750744AbWJOMD7 (ORCPT ); Sun, 15 Oct 2006 08:03:59 -0400 Received: from [192.168.1.65] ([192.168.1.65]) by localhost.localdomain (8.13.1/8.13.1) with ESMTP id k9FBwXH7022504 for ; Sun, 15 Oct 2006 21:58:33 +1000 Sender: linux-scsi-owner@vger.kernel.org List-Id: linux-scsi@vger.kernel.org To: linux-scsi@vger.kernel.org Hi All, Thanks for all your support for my previous posts. I have two questions. 1. Is it safe to assume that all the SG elements of request_buffer are page aligned? (Except the first one and last one), I mean, it is always multiple of pages? 2. What are situations reading a scsi disk (using dd ) cause a write to the disk? When I read my virtual scsi disk using dd command, block layer is generating lot of SCSI write, as well as reads. Any thoughts? Besides this observation, everything is working fine. Thanks in advance. Aboo