Re: [Qemu-block] [Patch for-2.5 v2 3/6] Add new block driver interface to add/delete a BDS's child

[Wen Congyang]

On 09/08/2015 11:52 PM, Eric Blake wrote:
> On 09/08/2015 03:10 AM, Wen Congyang wrote:
> 
>>> Design-wise, I think we really want to have the add-child operation be
>>> handed a pre-opened BDS, rather than the options dictionary to open the
>>> BDS itself.  That is, we should use the existing blockdev-add (and
>>> enhance it to support everything) to open the BDS, and then this command
>>> should just attach that BDS as the new child (which is why it IS
>>> important that we validate that the new BDS being added doesn't create
>>> an invalid loop).
>>>
>>
>> How to check it? The parent BDS can get all children. But the child doesn't
>> know if it is some BDS's child.
> 
> If I'm not mistaken, a child DOES know what its parent(s) are, once we
> have Max's series for NULL BDS representing a BB without media.
> 

Which patch? I don't find it.

Thanks
Wen Congyang