Re: [PATCH] hw/qdev-core: Add compatibility for (non)-transitional devs

[Michael S. Tsirkin]

On Tue, Oct 19, 2021 at 11:46:17AM +0100, Stefan Hajnoczi wrote:
> On Tue, Oct 12, 2021 at 10:36:01AM +0200, Jean-Louis Dupond wrote:
> > Forgot to CC maintainers.
> 
> Also CCing Jason Wang and Michael Tsirkin for VIRTIO.
> 
> Stefan

OMG
where all compat properties broken all the time?


> > 
> > On 12/10/2021 10:24, Jean-Louis Dupond wrote:
> > > hw_compat modes only take into account their base name.
> > > But if a device is created with (non)-transitional, then the compat
> > > values are not used, causing migrating issues.
> > > 
> > > This commit adds their (non)-transitional entries with the same settings
> > > as the base entry.
> > > 
> > > Fixes https://bugzilla.redhat.com/show_bug.cgi?id=1999141
> > > 
> > > Signed-off-by: Jean-Louis Dupond <jean-louis@dupond.be>
> > > ---
> > >   include/hw/qdev-core.h | 34 ++++++++++++++++++++++++++++++++++
> > >   1 file changed, 34 insertions(+)
> > > 
> > > diff --git a/include/hw/qdev-core.h b/include/hw/qdev-core.h
> > > index 4ff19c714b..5726825c2d 100644
> > > --- a/include/hw/qdev-core.h
> > > +++ b/include/hw/qdev-core.h
> > > @@ -293,6 +293,30 @@ typedef struct GlobalProperty {
> > >       bool optional;
> > >   } GlobalProperty;
> > > +
> > > +/**
> > > + * Helper to add (non)transitional compat properties
> > > + */
> > > +static inline void
> > > +compat_props_add_transitional(GPtrArray *arr, GlobalProperty *prop)
> > > +{
> > > +    GlobalProperty *transitional = g_new0(typeof(*transitional), 1);
> > > +    transitional->driver = g_strdup_printf("%s-transitional", 
> > > prop->driver);
> > > +    transitional->property = g_strdup(prop->property);
> > > +    transitional->value = g_strdup(prop->value);
> > > +    transitional->used = prop->used;
> > > +    transitional->optional = prop->optional;
> > > +    g_ptr_array_add(arr, (void *)transitional);
> > > +
> > > +    GlobalProperty *non_transitional = g_new0(typeof(*non_transitional), 
> > > 1);
> > > +    non_transitional->driver = g_strdup_printf("%s-non-transitional", 
> > > prop->driver);
> > > +    non_transitional->property = g_strdup(prop->property);
> > > +    non_transitional->value = g_strdup(prop->value);
> > > +    non_transitional->used = prop->used;
> > > +    non_transitional->optional = prop->optional;
> > > +    g_ptr_array_add(arr, (void *)non_transitional);
> > > +}
> > > +
> > >   static inline void
> > >   compat_props_add(GPtrArray *arr,
> > >                    GlobalProperty props[], size_t nelem)
> > > @@ -300,6 +324,16 @@ compat_props_add(GPtrArray *arr,
> > >       int i;
> > >       for (i = 0; i < nelem; i++) {
> > >           g_ptr_array_add(arr, (void *)&props[i]);
> > > +        if (g_str_equal(props[i].driver, "vhost-user-blk-pci") ||
> > > +            g_str_equal(props[i].driver, "virtio-scsi-pci") ||
> > > +            g_str_equal(props[i].driver, "virtio-blk-pci") ||
> > > +            g_str_equal(props[i].driver, "virtio-balloon-pci") ||
> > > +            g_str_equal(props[i].driver, "virtio-serial-pci") ||
> > > +            g_str_equal(props[i].driver, "virtio-9p-pci") ||
> > > +            g_str_equal(props[i].driver, "virtio-net-pci") ||
> > > +            g_str_equal(props[i].driver, "virtio-rng-pci")) {
> > > +            compat_props_add_transitional(arr, &props[i]);
> > > +        }
> > >       }
> > >   }
> >