From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-2.2 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,USER_AGENT_MUTT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id A0D05C43613 for ; Mon, 24 Jun 2019 10:22:16 +0000 (UTC) Received: from lists.gnu.org (lists.gnu.org [209.51.188.17]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 3901F20645 for ; Mon, 24 Jun 2019 10:22:16 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 3901F20645 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=redhat.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Received: from localhost ([::1]:49522 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.86_2) (envelope-from ) id 1hfM74-0002hz-NS for qemu-devel@archiver.kernel.org; Mon, 24 Jun 2019 06:22:14 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]:41401) by lists.gnu.org with esmtp (Exim 4.86_2) (envelope-from ) id 1hfM3x-0001Ej-8n for qemu-devel@nongnu.org; Mon, 24 Jun 2019 06:19:02 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1hfM3w-0008Us-1O for qemu-devel@nongnu.org; Mon, 24 Jun 2019 06:19:01 -0400 Received: from mx1.redhat.com ([209.132.183.28]:58520) by eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1hfM3t-0008LS-G4; Mon, 24 Jun 2019 06:18:57 -0400 Received: from smtp.corp.redhat.com (int-mx06.intmail.prod.int.phx2.redhat.com [10.5.11.16]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id 1C6CA81DF5; Mon, 24 Jun 2019 10:18:51 +0000 (UTC) Received: from linux.fritz.box (ovpn-117-91.ams2.redhat.com [10.36.117.91]) by smtp.corp.redhat.com (Postfix) with ESMTPS id 380A75C225; Mon, 24 Jun 2019 10:18:47 +0000 (UTC) Date: Mon, 24 Jun 2019 12:18:45 +0200 From: Kevin Wolf To: Laszlo Ersek , qemu-devel@nongnu.org, Keith Busch , Max Reitz , qemu-block@nongnu.org, Markus Armbruster Message-ID: <20190624101828.GC12855@linux.fritz.box> References: <20190617081205.GA26990@apples.localdomain> <20190624080154.GA4263@apples.localdomain> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20190624080154.GA4263@apples.localdomain> User-Agent: Mutt/1.11.3 (2019-02-01) X-Scanned-By: MIMEDefang 2.79 on 10.5.11.16 X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.5.110.25]); Mon, 24 Jun 2019 10:18:51 +0000 (UTC) X-detected-operating-system: by eggs.gnu.org: GNU/Linux 2.2.x-3.x [generic] X-Received-From: 209.132.183.28 Subject: Re: [Qemu-devel] [Qemu-block] [RFC] nvme: how to support multiple namespaces X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.23 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: "Qemu-devel" Am 24.06.2019 um 10:01 hat Klaus Birkelund geschrieben: > On Thu, Jun 20, 2019 at 05:37:24PM +0200, Laszlo Ersek wrote: > > On 06/17/19 10:12, Klaus Birkelund wrote: > > > Hi all, > > > > > > I'm thinking about how to support multiple namespaces in the NVMe > > > device. My first idea was to add a "namespaces" property array to the > > > device that references blockdevs, but as Laszlo writes below, this might > > > not be the best idea. It also makes it troublesome to add per-namespace > > > parameters (which is something I will be required to do for other > > > reasons). Some of you might remember my first attempt at this that > > > included adding a new block driver (derived from raw) that could be > > > given certain parameters that would then be stored in the image. But I > > > understand that this is a no-go, and I can see why. > > > > > > I guess the optimal way would be such that the parameters was something > > > like: > > > > > > -blockdev raw,node-name=blk_ns1,file.driver=file,file.filename=blk_ns1.img > > > -blockdev raw,node-name=blk_ns2,file.driver=file,file.filename=blk_ns2.img > > > -device nvme-ns,drive=blk_ns1,ns-specific-options (nsfeat,mc,dlfeat)... > > > -device nvme-ns,drive=blk_ns2,... > > > -device nvme,... > > > > > > My question is how to state the parent/child relationship between the > > > nvme and nvme-ns devices. I've been looking at how ide and virtio does > > > this, and maybe a "bus" is the right way to go? > > > > I've added Markus to the address list, because of this question. No > > other (new) comments from me on the thread starter at this time, just > > keeping the full context. > > > > Hi all, > > I've succesfully implemented this by introducing a new 'nvme-ns' device > model. The nvme device creates a bus named from the device id ('id' > parameter) and the nvme-ns devices are then registered on this. > > This results in an nvme device being creates like this (two namespaces > example): > > -drive file=nvme0n1.img,if=none,id=disk1 > -drive file=nvme0n2.img,if=none,id=disk2 > -device nvme,serial=deadbeef,id=nvme0 > -device nvme-ns,drive=disk1,bus=nvme0,nsid=1 > -device nvme-ns,drive=disk2,bus=nvme0,nsid=2 > > How does that look as a way forward? This looks very similar to what other devices do (one bus controller that has multiple devices on its but), so I like it. The thing that is special here is that -device nvme is already a block device by itself that can take a drive property. So how does this play together? Can I choose to either specify a drive directly for the nvme device or nvme-ns devices, but when I do both, I will get an error? What happens if I don't specify a drive for nvme, but also don't add nvme-ns devices? Kevin