From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751687Ab2GBLSX (ORCPT ); Mon, 2 Jul 2012 07:18:23 -0400 Received: from bedivere.hansenpartnership.com ([66.63.167.143]:57652 "EHLO bedivere.hansenpartnership.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750890Ab2GBLSV (ORCPT ); Mon, 2 Jul 2012 07:18:21 -0400 Message-ID: <1341227897.2987.15.camel@dabdike.int.hansenpartnership.com> Subject: Re: [PATCH] SCSI: Add SG_GET_SG_MAX_SEGMENT_SIZE ioctl to sg device From: James Bottomley To: Cong Meng Cc: stefanha@linux.vnet.ibm.com, linuxram@us.ibm.com, linux-kernel@vger.kernel.org, linux-scsi@vger.kernel.org, senwang@linux.vnet.ibm.com Date: Mon, 02 Jul 2012 12:18:17 +0100 In-Reply-To: <1341220857-1205-1-git-send-email-mc@linux.vnet.ibm.com> References: <1341220857-1205-1-git-send-email-mc@linux.vnet.ibm.com> Content-Type: text/plain; charset="UTF-8" X-Mailer: Evolution 3.2.3 Content-Transfer-Encoding: 7bit Mime-Version: 1.0 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Mon, 2012-07-02 at 17:20 +0800, Cong Meng wrote: > Add a new ioctl cmd to get the max segment size. It's useful in > virtualization environment for guest to know the queue limits, so > that the guest kicks off legal scsi command to a sg device. What's wrong with simply looking in the /sys for this? Plus, if you can come up with a justifiable reason, this needs to be in block as well so we can send it to all SCSI devices regardless of what ULD people use. James