Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752752AbZDMPiU (ORCPT ); Mon, 13 Apr 2009 11:38:20 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1752603AbZDMPiE (ORCPT ); Mon, 13 Apr 2009 11:38:04 -0400 Received: from bedivere.hansenpartnership.com ([66.63.167.143]:45057 "EHLO bedivere.hansenpartnership.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752569AbZDMPiB (ORCPT ); Mon, 13 Apr 2009 11:38:01 -0400 Subject: Re: Implementing NVMHCI... From: James Bottomley To: Linus Torvalds Cc: Avi Kivity , Alan Cox , Szabolcs Szakacsits , Grant Grundler , Linux IDE mailing list , LKML , Jens Axboe , Arjan van de Ven In-Reply-To: References: <20090412091228.GA29937@elte.hu> <20090412162018.6c1507b4@lxorguk.ukuu.org.uk> <49E213AE.4060506@redhat.com> <49E2DC96.6090407@redhat.com> Content-Type: text/plain Date: Mon, 13 Apr 2009 10:38:02 -0500 Message-Id: <1239637082.3278.36.camel@mulgrave.int.hansenpartnership.com> Mime-Version: 1.0 X-Mailer: Evolution 2.22.3.1 (2.22.3.1-1.fc9) Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1236 Lines: 27 On Mon, 2009-04-13 at 08:10 -0700, Linus Torvalds wrote: > On Mon, 13 Apr 2009, Avi Kivity wrote: > > > Of course, the _really_ conclusive thing (in a virtualized environment) is > > > to just make the virtual disk only able to do 16kB IO accesses (and with > > > 16kB alignment). IOW, actually emulate a disk with a 16kB hard sector size, > > > and reporting a 16kB sector size to the READ CAPACITY command. If it works > > > then, then clearly WNT has no issues with bigger sectors. > > > > I don't think IDE supports this? And Windows 2008 doesn't like the LSI > > emulated device we expose. > > Yeah, you'd have to have the OS use the SCSI commands for disk discovery, > so at least a SATA interface. With IDE disks, the sector size always has > to be 512 bytes, I think. Actually, the latest ATA rev supports different sector sizes in preparation for native 4k sector size SATA disks (words 117-118 of IDENTIFY). Matthew Wilcox already has the patches for libata ready. James -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/