Re: [Qemu-devel] [PATCH 4/7] qdev: Introduce DEFINE_PROP_LINK

[Paolo Bonzini]

On 28/06/2017 16:02, Fam Zheng wrote:
>>> It's implemented by creating a wrapper property that basically forwards
>>> operations to a QOM "link-FOO" property, which handles the check
>>> callback and flags. The feature that is missing from QOM is the dynamic
>>> child pointer which is done in the added code with the usual "offset"
>>> approach.
>> Would it be possible to add a ".create" field to PropertyInfo?  Then
>> there's no need to introduce the wrapper.
> QOM setter/getter want a LinkProperty opaque pointer, but qdev uses a Property
> pointer. I don't see a way to adapt that with .create(). Can you elaborate?

The .create() callback would call object_property_add_link directly.
There would be no change in the properties at the QOM level, but the
PropertyInfo lets "info qtree" show the property.

Paolo