From mboxrd@z Thu Jan  1 00:00:00 1970
Received: from eggs.gnu.org ([2001:4830:134:3::10]:41119)
	by lists.gnu.org with esmtp (Exim 4.71)
	(envelope-from <namei.unix@gmail.com>) id 1UkaRX-0007NQ-Qb
	for qemu-devel@nongnu.org; Thu, 06 Jun 2013 09:41:34 -0400
Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71)
	(envelope-from <namei.unix@gmail.com>) id 1UkaRS-0004Pl-09
	for qemu-devel@nongnu.org; Thu, 06 Jun 2013 09:41:31 -0400
Received: from mail-pd0-f177.google.com ([209.85.192.177]:35960)
	by eggs.gnu.org with esmtp (Exim 4.71)
	(envelope-from <namei.unix@gmail.com>) id 1UkaRR-0004Pd-Q6
	for qemu-devel@nongnu.org; Thu, 06 Jun 2013 09:41:25 -0400
Received: by mail-pd0-f177.google.com with SMTP id u10so3376801pdi.36
	for <qemu-devel@nongnu.org>; Thu, 06 Jun 2013 06:41:25 -0700 (PDT)
Message-ID: <51B0917F.7080402@gmail.com>
Date: Thu, 06 Jun 2013 21:41:19 +0800
From: Liu Yuan <namei.unix@gmail.com>
MIME-Version: 1.0
References: <1370519849-10620-1-git-send-email-namei.unix@gmail.com>
	<1370519849-10620-3-git-send-email-namei.unix@gmail.com>
	<20130606124629.GE2586@dhcp-200-207.str.redhat.com>
In-Reply-To: <20130606124629.GE2586@dhcp-200-207.str.redhat.com>
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 7bit
Subject: Re: [Qemu-devel] [PATCH 2/2] sheepdog: support 'qemu-img snapshot
	-a'
List-Id: <qemu-devel.nongnu.org>
List-Unsubscribe: <https://lists.nongnu.org/mailman/options/qemu-devel>,
	<mailto:qemu-devel-request@nongnu.org?subject=unsubscribe>
List-Archive: <http://lists.nongnu.org/archive/html/qemu-devel>
List-Post: <mailto:qemu-devel@nongnu.org>
List-Help: <mailto:qemu-devel-request@nongnu.org?subject=help>
List-Subscribe: <https://lists.nongnu.org/mailman/listinfo/qemu-devel>,
	<mailto:qemu-devel-request@nongnu.org?subject=subscribe>
To: Kevin Wolf <kwolf@redhat.com>
Cc: Stefan Hajnoczi <stefanha@redhat.com>, sheepdog@lists.wpkg.org, qemu-devel@nongnu.org, MORITA Kazutaka <morita.kazutaka@lab.ntt.co.jp>

On 06/06/2013 08:46 PM, Kevin Wolf wrote:
> I'm not sure how snapshots work internally for Sheepdog, but it seems
> odd to me that you need to do this only for disk-only snapshots, but not
> when the snapshot has VM state. (Also, note that 'qemu-img snapshot -a'
> works on images with a VM state, so the comment doesn't seem to be
> completely accurate)

Seems that I misunderstood your comments. What my 2/2 patch tried to do
is enable 'qemu-img snapshot -a' to rollback the sheepdog disk states
only and it is correct. So what I need fixing is comment, right?

how about the commenting as 'qemu-img asks us to rollback disk only, we
can't rely on the write request to sd_create_branch, so just call it
directly' ?

Thanks,
Yuan