From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:42001) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1W0mVX-0004Sr-VJ for qemu-devel@nongnu.org; Wed, 08 Jan 2014 01:20:57 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1W0mVR-0003zX-Q2 for qemu-devel@nongnu.org; Wed, 08 Jan 2014 01:20:51 -0500 Received: from mx1.redhat.com ([209.132.183.28]:3366) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1W0mVR-0003zR-H1 for qemu-devel@nongnu.org; Wed, 08 Jan 2014 01:20:45 -0500 Received: from int-mx02.intmail.prod.int.phx2.redhat.com (int-mx02.intmail.prod.int.phx2.redhat.com [10.5.11.12]) by mx1.redhat.com (8.14.4/8.14.4) with ESMTP id s086KiPV007169 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-SHA bits=256 verify=OK) for ; Wed, 8 Jan 2014 01:20:45 -0500 Message-ID: <52CCEE2B.5030609@redhat.com> Date: Wed, 08 Jan 2014 14:20:27 +0800 From: Fam Zheng MIME-Version: 1.0 References: <1389152570-1815-1-git-send-email-famz@redhat.com> In-Reply-To: <1389152570-1815-1-git-send-email-famz@redhat.com> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: quoted-printable Subject: Re: [Qemu-devel] [PATCH v10 00/11] 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: qemu-devel@nongnu.org Cc: kwolf@redhat.com, rjones@redhat.com, armbru@redhat.com, imain@redhat.com, stefanha@redhat.com, pbonzini@redhat.com On 2014=E5=B9=B401=E6=9C=8808=E6=97=A5 11:42, 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 target= ). > > 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 omit= explicitly > providing the size by ourselves, but it's risky because RUNNING-VM= .qcow2 is > used r/w by guest. Whether or not setting backing file in the imag= e 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 overr= ide > backing_hd for added drive) > > 3. (QMP) blockdev-backup device=3Dsource-drive sync=3Dnone target=3Dt= arget0 > > (this is the QMP command introduced by this series, which use a na= med > device as target of drive-backup) > > 4. (QMP) nbd-server-add device=3Dtarget0 > > When image fleecing done: > > 1. (QMP) block-job-cancel device=3Dsource-drive > > 2. (HMP) drive_del target0 > > 3. (SHELL) rm BACKUP.qcow2 > > v8 -> v10: Rebased to qemu.git. Address Stefan's comments: > > [01/11] block: Add BlockOpType enum > Change enum definition as internal. > > [05/11] block: Add bdrv_set_backing_hd() > Set bs->backing_file and bs->backing_format. > > [06/11] block: Add backing_blocker in BlockDriverState > Reuse bdrv_set_backing_hd(). > > [07/11] block: Parse "backing" option to reference existing BDS > Fix use-after-free. > Check for "backing=3D" and "backing.file=3D" conflict. > Remove unintended bdrv_swap hunks. Actually it is not unintended, this breaks qemu-iotests 040. The asserts=20 have to be removed to allow block commit. Will respin, sorry for posting three revisions in a row. Fam > > [08/11] block: Support dropping active in bdrv_drop_intermediate > Fix function comment. > > [09/11] stream: Use bdrv_drop_intermediate and drop close_unused_i= mages > > > Fam Zheng (11): > block: Add BlockOpType enum > block: Introduce op_blockers to BlockDriverState > block: Replace in_use with operation blocker > block: Move op_blocker check from block_job_create to its caller > block: Add bdrv_set_backing_hd() > block: Add backing_blocker in BlockDriverState > block: Parse "backing" option to reference existing BDS > block: Support dropping active in bdrv_drop_intermediate > stream: Use bdrv_drop_intermediate and drop close_unused_images > qmp: Add command 'blockdev-backup' > block: Allow backup on referenced named BlockDriverState > > block-migration.c | 7 +- > block.c | 306 +++++++++++++++++++++++++++----= --------- > block/backup.c | 21 +++ > block/commit.c | 1 + > block/stream.c | 28 +--- > blockdev.c | 70 +++++++-- > blockjob.c | 14 +- > hw/block/dataplane/virtio-blk.c | 19 ++- > include/block/block.h | 29 +++- > include/block/block_int.h | 9 +- > include/block/blockjob.h | 3 + > qapi-schema.json | 49 +++++++ > qmp-commands.hx | 44 ++++++ > 13 files changed, 446 insertions(+), 154 deletions(-) >