Re: [PATCH RFC server v2 04/11] vfio-user: find and init PCI device

[Jag Raman]

> On Sep 8, 2021, at 8:43 AM, Stefan Hajnoczi <stefanha@redhat.com> wrote:
> 
> On Fri, Aug 27, 2021 at 01:53:23PM -0400, Jagannathan Raman wrote:
>> @@ -96,6 +102,28 @@ static void vfu_object_machine_done(Notifier *notifier, 
>> void *data)
>>                    strerror(errno));
>>         return;
>>     }
>> +
>> +    dev = qdev_find_recursive(sysbus_get_default(), o->devid);
>> +    if (dev == NULL) {
>> +        error_setg(&error_abort, "vfu: Device %s not found", o->devid);
>> +        return;
>> +    }
>> +
>> +    if (!object_dynamic_cast(OBJECT(dev), TYPE_PCI_DEVICE)) {
>> +        error_setg(&error_abort, "vfu: %s not a PCI devices", o->devid);
>> +        return;
>> +    }
>> +
>> +    o->pci_dev = PCI_DEVICE(dev);
>> +
>> +    ret = vfu_pci_init(o->vfu_ctx, VFU_PCI_TYPE_CONVENTIONAL,
>> +                       PCI_HEADER_TYPE_NORMAL, 0);
> 
> What is needed to support PCI Express?

I think we could check if o->pci_dev supports QEMU_PCI_CAP_EXPRESS,
and based on that choose if we should use
VFU_PCI_TYPE_CONVENTIONAL or VFU_PCI_TYPE_EXPRESS.

pci_is_express() is already doing that, although it’s a private function
now. It’s a good time to export it.

--
Jag