Hi,
> >
> > virtio-$device-{pci, s390, ccw} all duplicate the
> > qdev properties of their virtio child. This approach does
> > not work well with string or pointer properties since we
> > must be careful about leaking or double-freeing them.
> >
> > Use the QOM alias property to forward property accesses to the
> > VirtIORNG child. This way no duplication is necessary.
> >
> > For their child, object_initialize() leaves the object with a refcount of 1.
> > object_property_add_child() adds its own reference which is dropped
> > again when the property is deleted.
> >
> > The upshot of this is that we always have a refcount >= 1. Upon hot
> > unplug the virtio-$device child is not finalized!
> >
> > Drop our reference after the child property has been added to the
> > parent.
> >
> > Attention please:
> > As Michael's comments, the patches will introduce regresion about
> > "-device FOO,help", which had been fixed by my other patch series:
> > [PATCH v2 0/7] add description field in ObjectProperty and PropertyInfo
> struct
> > http://lists.nongnu.org/archive/html/qemu-devel/2014-09/msg04908.html
> >
> > Acknowledgements:
> > I copied Stefan's commit c5d49db message about virtio-blk which
> > summarized reasons very well, I cannot agree more with him.
> > Holp Stefan do not mind, thanks!
> >
> > Please review, Thanks a lot!
>
> Do you have a git branch for quick testing?
>
Sorry, I havn't. :(
I worked this in the environment of my company,
then send patches.
Would you apply those patches based qemu master by 'git am' ?
Thanks!
> > -Gonglei
> >
> > Gonglei (9):
> > virtio-net: use aliases instead of duplicate qdev properties
> > virtio: fix virtio-net child refcount in transports
> > virtio/vhost scsi: use aliases instead of duplicate qdev properties
> > virtio/vhost-scsi: fix virtio-scsi/vhost-scsi child refcount in
> > transports
> > virtio-serial: use aliases instead of duplicate qdev properties
> > virtio-serial: fix virtio-serial child refcount in transports
> > virtio-rng: use aliases instead of duplicate qdev properties
> > virtio-rng: fix virtio-rng child refcount in transports
> > virtio-balloon: fix virtio-balloon child refcount in transports
> >
> > hw/s390x/s390-virtio-bus.c | 16 ++++++++++------
> > hw/s390x/virtio-ccw.c | 18 +++++++++++-------
> > hw/virtio/virtio-pci.c | 18 +++++++++++-------
> > 3 files changed, 32 insertions(+), 20 deletions(-)
>
> One thing I noticed is that the various devices end up with similar
> code in the end:
>
> object_initialize(&dev->vdev, sizeof(dev->vdev), TYPE_WHATEVER);
> object_property_add_child(obj, "virtio-backend", OBJECT(&dev->vdev),
> NULL);
> object_unref(OBJECT(&dev->vdev));
> qdev_alias_all_properties(DEVICE(&dev->vdev), obj);
>
> Would it make sense to add a helper function for that?
Yes. I think it make sense.
Maybe I can add a helper function in virtio.c, named
virtio_backend_init(). Agree? Thanks!
Best regards,
-Gonglei
