Re: [Qemu-devel] [PATCH 4/7] virtio-blk: use aliases instead of duplicate qdev properties

[Andreas Färber]

Am 22.05.2014 00:04, schrieb Paolo Bonzini:
> Il 21/05/2014 22:22, Stefan Hajnoczi ha scritto:
>> virtio-blk-pci, virtio-blk-s390, and virtio-blk-ccw all duplicate the
>> qdev properties of their VirtIOBlock child.  This approach does not work
>> well with string or pointer properties since we must be careful about
>> leaking or double-freeing them.
>>
>> Use the QOM alias property to forward property accesses to the
>> VirtIOBlock child.  This way no duplication is necessary.
>>
>> Remember to stop calling virtio_blk_set_conf() so that we don't clobber
>> the values already set on the VirtIOBlock instance.
> 
> Which properties are _not_ being added?  This is probably needed for all
> other virtio devices so a generic solution would be nice.

"type", "realized" and the child<> property for VirtIODevice come to
mind, possibly one or two more.

If we follow a generic scheme, we could add an .instance_post_init hook
for VirtIOPCIProxy iterating over all properties and blacklisting some.

Regards,
Andreas

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