Re: [Qemu-devel] [PATCH v11 00/11] Drop in_use from BlockDriverState and enable point-in-time snapshot exporting over NBD

[Kevin Wolf]

Am 24.01.2014 um 11:10 hat Fam Zheng geschrieben:
> Ping?

This doesn't apply on top of the block branch any more. Can you rebase,
please?

Kevin

> On Wed, 01/08 18:07, 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 <source size here>
> > 
> >     (Alternatively we can use -o backing_file=RUNNING-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 image file
> >     doesn't matter, as we are going to override the backing hd in the next
> >     step)
> > 
> >  2. (QMP) blockdev-add backing=source-drive file.driver=file 
> > file.filename=BACKUP.qcow2 id=target0 if=none driver=qcow2
> > 
> >     (where source-drive is the running BlockDriverState name for
> >     RUNNING-VM.img. This patch implements "backing=" option to override
> >     backing_hd for added drive)
> > 
> >  3. (QMP) blockdev-backup device=source-drive sync=none target=target0
> > 
> >     (this is the QMP command introduced by this series, which use a named
> >     device as target of drive-backup)
> > 
> >  4. (QMP) nbd-server-add device=target0
> > 
> > When image fleecing done:
> > 
> >  1. (QMP) block-job-cancel device=source-drive
> > 
> >  2. (HMP) drive_del target0
> > 
> >  3. (SHELL) rm BACKUP.qcow2
> > 
> > v8 -> v11: Rebased to qemu.git. Address Stefan's comments:
> >     (sorry for sending 3 revisions in a day)
> > 
> >     [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
> >             Update commit message about bdrv_swap assertion removal.
> >             Fix use-after-free.
> >             Check for "backing=" and "backing.file=" conflict.
> > 
> >     [08/11] block: Support dropping active in bdrv_drop_intermediate
> >             Fix function comment.
> > 
> >     [09/11] stream: Use bdrv_drop_intermediate and drop close_unused_images
> > 
> > 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                         | 304 
> > +++++++++++++++++++++++++++-------------
> >  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, 444 insertions(+), 154 deletions(-)
> > 
> > -- 
> > 1.8.5.1
> > 
> >