Re: [Qemu-devel] [PATCH] virtio: set virtio-net/virtio-mmio host features

[Mario Smarduch <m.smarduch@samsung.com>]

On 02/20/2014 02:10 PM, Peter Maydell wrote:
> On 20 February 2014 21:59, Mario Smarduch <m.smarduch@samsung.com> wrote:
>> On 02/20/2014 11:35 AM, Peter Maydell wrote:
>>> On 20 February 2014 19:09, Mario Smarduch <m.smarduch@samsung.com> wrote:
>>>> host features since you don't know what virtio device will be plugged
>>>> in later.
>>>
>>> I think this function is the right place to set these properties,
>>> yes. What I'm saying is that I don't see why you're doing it
>>> this way rather than using the existing per-backend hook.
>>> Maybe there's a reason not to use that hook, but you don't say.
>>>
>>
>> Appears virtio-net beckend hooks are common to several transports,
>> and would require virtio-mmio exception to set the host_features.
>> If I'm missing something please recommend.
> 
> Yes, they're supposed to be common across transports, because
> the backend isn't supposed to care about which transport in
> particular. If there's a condition where the backend needs to
> do something which only happens for one transport, maybe we
> need a new hook.

So something like set_transport_features(...) in VirtiIODeviceClass,
and call it from the realize hook where you can access
the virtio-mmio transport class instance.

> 
> thanks
> -- PMM
>