Re: [Qemu-devel] [PATCH 01/13] [S390] Add hotplug support

[Anthony Liguori]

On 11/13/2011 09:33 AM, Alexander Graf wrote:
> I just submitted a few patches that enable the s390 virtio bus to receive
> a hotplug add event. This patch implements the qemu side of it, so that new
> hotplug events can be submitted to the guest.
>
> Signed-off-by: Alexander Graf<address@hidden>

How is this not a feature?  This is adding hot plug support for virtio-s390, no?

Regards,

Anthony Liguori

> ---
>
> v1 ->  v2:
>
>    - make s390 virtio hoplug code emulate-capable
> ---
>   hw/s390-virtio-bus.c |   24 +++++++++++++++++++-----
>   hw/s390-virtio-bus.h |    5 +++++
>   2 files changed, 24 insertions(+), 5 deletions(-)
>
> diff --git a/hw/s390-virtio-bus.c b/hw/s390-virtio-bus.c
> index 0ce6406..3760561 100644
> --- a/hw/s390-virtio-bus.c
> +++ b/hw/s390-virtio-bus.c
> @@ -82,12 +82,24 @@ VirtIOS390Bus *s390_virtio_bus_init(ram_addr_t *ram_size)
>       bus->dev_offs = bus->dev_page;
>       bus->next_ring = bus->dev_page + TARGET_PAGE_SIZE;
>
> +    /* Enable hotplugging */
> +    _bus->allow_hotplug = 1;
> +
>       /* Allocate RAM for VirtIO device pages (descriptors, queues, rings) */
>       *ram_size += S390_DEVICE_PAGES * TARGET_PAGE_SIZE;
>
>       return bus;
>   }
>
> +static void s390_virtio_irq(CPUState *env, int config_change, uint64_t token)
> +{
> +    if (kvm_enabled()) {
> +        kvm_s390_virtio_irq(env, config_change, token);
> +    } else {
> +        cpu_inject_ext(env, VIRTIO_EXT_CODE, config_change, token);
> +    }
> +}
> +
>   static int s390_virtio_device_init(VirtIOS390Device *dev, VirtIODevice *vdev)
>   {
>       VirtIOS390Bus *bus;
> @@ -109,6 +121,11 @@ static int s390_virtio_device_init(VirtIOS390Device *dev, 
> VirtIODevice *vdev)
>       dev->host_features = vdev->get_features(vdev, dev->host_features);
>       s390_virtio_device_sync(dev);
>
> +    if (dev->qdev.hotplugged) {
> +        CPUState *env = s390_cpu_addr2state(0);
> +        s390_virtio_irq(env, VIRTIO_PARAM_DEV_ADD, dev->dev_offs);
> +    }
> +
>       return 0;
>   }
>
> @@ -313,11 +330,7 @@ static void virtio_s390_notify(void *opaque, uint16_t 
> vector)
>       uint64_t token = s390_virtio_device_vq_token(dev, vector);
>       CPUState *env = s390_cpu_addr2state(0);
>
> -    if (kvm_enabled()) {
> -        kvm_s390_virtio_irq(env, 0, token);
> -    } else {
> -        cpu_inject_ext(env, VIRTIO_EXT_CODE, 0, token);
> -    }
> +    s390_virtio_irq(env, 0, token);
>   }
>
>   static unsigned virtio_s390_get_features(void *opaque)
> @@ -385,6 +398,7 @@ static void 
> s390_virtio_bus_register_withprop(VirtIOS390DeviceInfo *info)
>   {
>       info->qdev.init = s390_virtio_busdev_init;
>       info->qdev.bus_info =&s390_virtio_bus_info;
> +    info->qdev.unplug = qdev_simple_unplug_cb;
>
>       assert(info->qdev.size>= sizeof(VirtIOS390Device));
>       qdev_register(&info->qdev);
> diff --git a/hw/s390-virtio-bus.h b/hw/s390-virtio-bus.h
> index f1bece7..d02a907 100644
> --- a/hw/s390-virtio-bus.h
> +++ b/hw/s390-virtio-bus.h
> @@ -35,6 +35,11 @@
>   #define VIRTIO_RING_LEN                       (TARGET_PAGE_SIZE * 3)
>   #define S390_DEVICE_PAGES             512
>
> +#define VIRTIO_PARAM_MASK               0xff
> +#define VIRTIO_PARAM_VRING_INTERRUPT    0x0
> +#define VIRTIO_PARAM_CONFIG_CHANGED     0x1
> +#define VIRTIO_PARAM_DEV_ADD            0x2
> +
>   typedef struct VirtIOS390Device {
>       DeviceState qdev;
>       ram_addr_t dev_offs;