On 08/31/2015 06:55 PM, Wen Congyang wrote:

>>> +This command is still a work in progress. It doesn't support all
>>> +block drivers. Stay away from it unless you want it to help with
>>> +its development.
>>
>> Maybe we should name it 'x-child-add' for now, so that we aren't baking
>> ourselves into a corner.
> 
> Do you mean the command name should be x-child-add? It is OK.

Use of the 'x-' prefix means a command is experimental and may change or
be withdrawn.  It gives us a way to test if an interface is useful
without committing to that interface long term.  We've still got time
before 2.5 to get blockdev-add working everywhere, in which case I think
we are better off using blockdev-add to create a new unattached BDS and
then have this command pass the node name to be made the new child,
rather than all the options for opening the child from scratch.

-- 
Eric Blake   eblake redhat com    +1-919-301-3266
Libvirt virtualization library http://libvirt.org