Re: [Qemu-devel] [PATCH v2 11/11] qmp: add command 'blockdev-backup'

[Wenchao Xia]

于 2013-7-18 12:41, Fam Zheng 写道:
> On Wed, 07/17 06:44, Eric Blake wrote:
> > On 07/17/2013 03:42 AM, Fam Zheng wrote:
> > > Similar to drive-backup, but this command uses a device id as target
> > > instead of creating/opening an image file.
> > >
> > > Signed-off-by: Fam Zheng <address@hidden>
> > > ---
> > >   blockdev.c       | 71 ++++++++++++++++++++++++++++++++++++++++++++++++++++++++
> > >   qapi-schema.json | 49 ++++++++++++++++++++++++++++++++++++++
> > >   qmp-commands.hx  | 22 ++++++++++++++++++
> > >   3 files changed, 142 insertions(+)
> >
> > > +++ b/qapi-schema.json
> > > @@ -1665,6 +1665,40 @@
> > >               '*on-target-error': 'BlockdevOnError' } }
> > >
> > >   ##
> > > +# @BlockdevBackup
> > > +#
> >
> > > +{ 'type': 'BlockdevBackup',
> > > +  'data': { 'device': 'str', 'target': 'str',
> > > +            'sync': 'MirrorSyncMode',
> > > +            '*speed': 'int',
> > > +            '*on-source-error': 'BlockdevOnError',
> > > +            '*on-target-error': 'BlockdevOnError' } }
> >
> > Seems okay.  But what is missing is the addition of this type into the
> > union used for 'transaction' - shouldn't it be possible to mix this with
> > other transaction capabilities?
>
> Should be possible, as users may want point-in-time snapshot of multiple
> disks. If this API looks OK, I will include it into transaction in the
> next version.
  Instead of add this new API, how about extend Driver-backup API? This
patch is basically doing similar things with driver-backup, extension
of old API will save trouble to do same things driver-backup already
does, such as support qmp_transaction.

--
Best Regards

Wenchao Xia