Re: [Qemu-devel] [PATCH v5 5/6] s390/virtio-ccw: Add hotplug handler

[Igor Mammedov <imammedo@redhat.com>]

On Thu, 18 Feb 2016 23:03:36 -0500
Matthew Rosato <mjrosato@linux.vnet.ibm.com> wrote:

> First consumer will be CPU hotplug, to update machine/cpu[n]
> links during cpu plug.
> 
> Signed-off-by: Matthew Rosato <mjrosato@linux.vnet.ibm.com>
> ---
>  hw/s390x/s390-virtio-ccw.c | 40 ++++++++++++++++++++++++++++++++++++++++
>  1 file changed, 40 insertions(+)
> 
> diff --git a/hw/s390x/s390-virtio-ccw.c b/hw/s390x/s390-virtio-ccw.c
> index b05ed8b..31c1082 100644
> --- a/hw/s390x/s390-virtio-ccw.c
> +++ b/hw/s390x/s390-virtio-ccw.c
> @@ -156,10 +156,46 @@ static void ccw_init(MachineState *machine)
>                      gtod_save, gtod_load, kvm_state);
>  }
>  
> +static void s390_cpu_plug(HotplugHandler *hotplug_dev,
> +                        DeviceState *dev, Error **errp)
> +{
> +    gchar *name;
> +    S390CPU *cpu = S390_CPU(dev);
> +    CPUState *cs = CPU(dev);
> +
> +    name = g_strdup_printf("cpu[%i]", cpu->env.cpu_num);
> +    object_property_set_link(OBJECT(qdev_get_machine()), OBJECT(cs), name,
> +                             errp);
> +}
> +
> +static void s390_machine_device_plug(HotplugHandler *hotplug_dev,
> +                                     DeviceState *dev, Error **errp)
> +{
> +    if (object_dynamic_cast(OBJECT(dev), TYPE_CPU)) {
> +        s390_cpu_plug(hotplug_dev, dev, errp);
> +    }
> +}
> +
> +static void s390_machine_device_unplug(HotplugHandler *hotplug_dev,
> +                                       DeviceState *dev, Error **errp)
> +{
> +
> +}
> +
> +static HotplugHandler *s390_get_hotplug_handler(MachineState *machine,
> +                                                DeviceState *dev)
> +{
> +    if (object_dynamic_cast(OBJECT(dev), TYPE_CPU)) {
> +        return HOTPLUG_HANDLER(machine);
> +    }
> +    return NULL;
> +}
> +
>  static void ccw_machine_class_init(ObjectClass *oc, void *data)
>  {
>      MachineClass *mc = MACHINE_CLASS(oc);
>      NMIClass *nc = NMI_CLASS(oc);
> +    HotplugHandlerClass *hc = HOTPLUG_HANDLER_CLASS(oc);
>  
>      mc->init = ccw_init;
>      mc->reset = s390_machine_reset;
> @@ -171,6 +207,9 @@ static void ccw_machine_class_init(ObjectClass *oc, void *data)
>      mc->no_sdcard = 1;
>      mc->use_sclp = 1;
>      mc->max_cpus = 255;
> +    mc->get_hotplug_handler = s390_get_hotplug_handler;
> +    hc->plug = s390_machine_device_plug;
> +    hc->unplug = s390_machine_device_unplug;
drop unplug handler as does nothing, if it's NULL then generic qdev code
will ignore it, see qdev_unplug().

>      nc->nmi_monitor_handler = s390_nmi;
>  }
>  
> @@ -232,6 +271,7 @@ static const TypeInfo ccw_machine_info = {
>      .class_init    = ccw_machine_class_init,
>      .interfaces = (InterfaceInfo[]) {
>          { TYPE_NMI },
> +        { TYPE_HOTPLUG_HANDLER},
>          { }
>      },
>  };