Re: [Qemu-devel] [PATCH v3 12/14] pvpanic: add API to access io port

["Michael S. Tsirkin" <mst@redhat.com>]

On Thu, Jul 25, 2013 at 12:29:52PM +0200, Gerd Hoffmann wrote:
> On 07/24/13 18:02, Michael S. Tsirkin wrote:
> > Add API to find pvpanic device and get its io port.
> > Will be used to fill in guest info structure.
> 
> > +uint16_t pvpanic_port(void)
> > +{
> > +    Object *o = object_resolve_path_type("", TYPE_ISA_PVPANIC_DEVICE, NULL);
> > +    PVPanicState *s;
> > +    if (!o) {
> > +        return 0;
> > +    }
> 
>        return object_property_get_int(o, "ioport");
> }
> 
> Then you don't need PVPanicState access and can place the code into
> acpi-build.c.
> 
> cheers,
>   Gerd

I can change the implementation but I don't think it's
a good idea to copy property names around:
it's too fragile, compiler won't warn us if we
change the name or value semantics, or make
a mistake in acpi-build.c
Same applies to TYPE_ISA_PVPANIC_DEVICE: better
to expose an API than expose the type externally.

-- 
MST