From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:47771) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1VrJ4l-0002xr-L5 for qemu-devel@nongnu.org; Thu, 12 Dec 2013 22:06:09 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1VrJ4f-0006qq-A5 for qemu-devel@nongnu.org; Thu, 12 Dec 2013 22:06:03 -0500 Received: from mx1.redhat.com ([209.132.183.28]:49360) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1VrJ4f-0006qe-13 for qemu-devel@nongnu.org; Thu, 12 Dec 2013 22:05:57 -0500 Received: from int-mx12.intmail.prod.int.phx2.redhat.com (int-mx12.intmail.prod.int.phx2.redhat.com [10.5.11.25]) by mx1.redhat.com (8.14.4/8.14.4) with ESMTP id rBD35tOd032040 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-SHA bits=256 verify=OK) for ; Thu, 12 Dec 2013 22:05:56 -0500 Message-ID: <52AA7980.4020507@redhat.com> Date: Fri, 13 Dec 2013 11:05:36 +0800 From: Fam Zheng MIME-Version: 1.0 References: <1386836626-6436-1-git-send-email-famz@redhat.com> <20131213024014.GA7812@gate.mains.priv> In-Reply-To: <20131213024014.GA7812@gate.mains.priv> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: quoted-printable Subject: Re: [Qemu-devel] [PATCH v7 00/10] Drop in_use from BlockDriverState and enable point-in-time snapshot exporting over NBD List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Ian Main Cc: kwolf@redhat.com, armbru@redhat.com, qemu-devel@nongnu.org, rjones@redhat.com, stefanha@redhat.com, pbonzini@redhat.com On 2013=E5=B9=B412=E6=9C=8813=E6=97=A5 10:40, Ian Main wrote: > On Thu, Dec 12, 2013 at 04:23:36PM +0800, Fam Zheng wrote: >> This series adds for point-in-time snapshot NBD exporting based on >> blockdev-backup (variant of drive-backup with existing device as targe= t). >> >> We get a thin point-in-time snapshot by COW mechanism of drive-backup,= and >> export it through built in NBD server. The steps are as below: >> >> 1. (SHELL) qemu-img create -f qcow2 BACKUP.qcow2 >> >> (Alternatively we can use -o backing_file=3DRUNNING-VM.img to omi= t explicitly >> providing the size by ourselves, but it's risky because RUNNING-V= M.qcow2 is >> used r/w by guest. Whether or not setting backing file in the ima= ge file >> doesn't matter, as we are going to override the backing hd in the= next >> step) >> >> 2. (QMP) blockdev-add backing=3Dsource-drive file.driver=3Dfile file= .filename=3DBACKUP.qcow2 id=3Dtarget0 if=3Dnone driver=3Dqcow2 >> >> (where source-drive is the running BlockDriverState name for >> RUNNING-VM.img. This patch implements "backing=3D" option to over= ride >> backing_hd for added drive) >> >> 3. (QMP) blockdev-backup device=3Dsource-drive sync=3Dnone target=3D= target0 >> >> (this is the QMP command introduced by this series, which use a n= amed >> device as target of drive-backup) >> >> 4. (QMP) nbd-server-add device=3Dtarget0 >> >> When image fleecing done: >> >> 1. (QMP) block-job-complete device=3Dsource-drive > > If you do another revision, this should be block-job-cancel. > OK, thanks for reminding. Fam