Re: [Qemu-devel] [PATCH v4 3/5] s390x: Add I/O adapter registration.

[Alexander Graf <agraf@suse.de>]

On 09.04.14 13:34, Cornelia Huck wrote:
> Register an I/O adapter interrupt source for when virtio-ccw devices start
> using adapter interrupts.
>
> Reviewed-by: Thomas Huth <thuth@linux.vnet.ibm.com>
> Signed-off-by: Cornelia Huck <cornelia.huck@de.ibm.com>
> ---
>   hw/intc/s390_flic.c   |   59 +++++++++++++++++++++++++++++++++++++++++++++++++
>   hw/s390x/css.c        |   51 ++++++++++++++++++++++++++++++++++++++++++
>   hw/s390x/css.h        |    4 ++++
>   hw/s390x/virtio-ccw.c |    4 ++++
>   hw/s390x/virtio-ccw.h |    1 +
>   target-s390x/cpu.h    |   33 +++++++++++++++++++++++++++
>   6 files changed, 152 insertions(+)
>
> diff --git a/hw/intc/s390_flic.c b/hw/intc/s390_flic.c
> index b2ef3e3..c033c8a 100644
> --- a/hw/intc/s390_flic.c
> +++ b/hw/intc/s390_flic.c
> @@ -21,6 +21,11 @@
>   #define FLIC_FAILED (-1UL)
>   #define FLIC_SAVEVM_VERSION 1
>   
> +static KVMS390FLICState *s390_get_flic(void)
> +{
> +    return KVM_S390_FLIC(object_resolve_path("/machine/s390-flic", NULL));
> +}
> +
>   void s390_flic_init(void)
>   {
>       DeviceState *dev;
> @@ -148,6 +153,60 @@ static int __get_all_irqs(KVMS390FLICState *flic,
>       return r;
>   }
>   
> +int kvm_s390_register_io_adapter(uint32_t id, uint8_t isc, bool swap,
> +                                 bool is_maskable)
> +{
> +    struct kvm_s390_io_adapter adapter = {
> +        .id = id,
> +        .isc = isc,
> +        .maskable = is_maskable,
> +        .swap = swap,
> +    };
> +    KVMS390FLICState *flic = s390_get_flic();
> +    int r, ret;
> +    struct kvm_device_attr attr = {
> +        .group = KVM_DEV_FLIC_ADAPTER_REGISTER,
> +        .addr = (uint64_t)&adapter,
> +    };
> +
> +    if (!flic) {
> +        return -ENOSYS;
> +    }
> +    if (!kvm_check_extension(kvm_state, KVM_CAP_IRQ_ROUTING)) {
> +        return -ENOSYS;
> +    }
> +
> +    r = ioctl(flic->fd, KVM_SET_DEVICE_ATTR, &attr);
> +
> +    ret = r ? -errno : 0;
> +    return ret;
> +}
> +
> +int kvm_s390_io_adapter_map(uint32_t id, uint64_t map_addr, bool do_map)
> +{
> +    struct kvm_s390_io_adapter_req req = {
> +        .id = id,
> +        .type = do_map ? KVM_S390_IO_ADAPTER_MAP : KVM_S390_IO_ADAPTER_UNMAP,
> +        .addr = map_addr,
> +    };
> +    KVMS390FLICState *flic = s390_get_flic();
> +    struct kvm_device_attr attr = {
> +        .group = KVM_DEV_FLIC_ADAPTER_MODIFY,
> +        .addr = (uint64_t)&req,
> +    };
> +    int r;
> +
> +    if (!flic) {
> +        return -ENOSYS;
> +    }
> +    if (!kvm_check_extension(kvm_state, KVM_CAP_IRQ_ROUTING)) {
> +        return -ENOSYS;
> +    }
> +
> +    r = ioctl(flic->fd, KVM_SET_DEVICE_ATTR, &attr);
> +    return r ? -errno : 0;
> +}
> +
>   /**
>    * kvm_flic_save - Save pending floating interrupts
>    * @f: QEMUFile containing migration state
> diff --git a/hw/s390x/css.c b/hw/s390x/css.c
> index 7074d2b..a6d173f 100644
> --- a/hw/s390x/css.c
> +++ b/hw/s390x/css.c
> @@ -39,6 +39,13 @@ typedef struct CssImage {
>       ChpInfo chpids[MAX_CHPID + 1];
>   } CssImage;
>   
> +typedef struct IoAdapter {
> +    uint32_t id;
> +    uint8_t type;
> +    uint8_t isc;
> +    QTAILQ_ENTRY(IoAdapter) sibling;
> +} IoAdapter;
> +
>   typedef struct ChannelSubSys {
>       QTAILQ_HEAD(, CrwContainer) pending_crws;
>       bool do_crw_mchk;
> @@ -49,6 +56,7 @@ typedef struct ChannelSubSys {
>       uint64_t chnmon_area;
>       CssImage *css[MAX_CSSID + 1];
>       uint8_t default_cssid;
> +    QTAILQ_HEAD(, IoAdapter) io_adapters;
>   } ChannelSubSys;
>   
>   static ChannelSubSys *channel_subsys;
> @@ -69,6 +77,48 @@ int css_create_css_image(uint8_t cssid, bool default_image)
>       return 0;
>   }
>   
> +int css_register_io_adapter(uint8_t type, uint8_t isc, bool swap,
> +                            bool maskable, uint32_t *id)
> +{
> +    IoAdapter *adapter;
> +    bool found = false;
> +    int ret;
> +
> +    *id = 0;
> +    QTAILQ_FOREACH(adapter, &channel_subsys->io_adapters, sibling) {
> +        if ((adapter->type == type) && (adapter->isc == isc)) {
> +            *id = adapter->id;
> +            found = true;
> +            ret = 0;
> +            break;
> +        }
> +        if (adapter->id >= *id) {
> +            *id = adapter->id + 1;
> +        }
> +    }
> +    if (found) {
> +        goto out;
> +    }
> +    adapter = g_new0(IoAdapter, 1);
> +    ret = s390_register_io_adapter(*id, isc, swap, maskable);
> +    if (ret == -ENOSYS) {
> +        /* Keep adapter even if we didn't register it anywhere. */
> +        ret = 0;
> +    }
> +    if (ret == 0) {
> +        adapter->id = *id;
> +        adapter->isc = isc;
> +        adapter->type = type;
> +        QTAILQ_INSERT_TAIL(&channel_subsys->io_adapters, adapter, sibling);
> +    } else {
> +        g_free(adapter);
> +        fprintf(stderr, "Unexpected error %d when registering adapter %d\n",
> +                ret, *id);
> +    }
> +out:
> +    return ret;
> +}
> +
>   uint16_t css_build_subchannel_id(SubchDev *sch)
>   {
>       if (channel_subsys->max_cssid > 0) {
> @@ -1239,6 +1289,7 @@ static void css_init(void)
>       channel_subsys->do_crw_mchk = true;
>       channel_subsys->crws_lost = false;
>       channel_subsys->chnmon_active = false;
> +    QTAILQ_INIT(&channel_subsys->io_adapters);
>   }
>   machine_init(css_init);
>   
> diff --git a/hw/s390x/css.h b/hw/s390x/css.h
> index e9b4405..380e8e7 100644
> --- a/hw/s390x/css.h
> +++ b/hw/s390x/css.h
> @@ -99,4 +99,8 @@ void css_generate_sch_crws(uint8_t cssid, uint8_t ssid, uint16_t schid,
>                              int hotplugged, int add);
>   void css_generate_chp_crws(uint8_t cssid, uint8_t chpid);
>   void css_adapter_interrupt(uint8_t isc);
> +
> +#define CSS_IO_ADAPTER_VIRTIO 1
> +int css_register_io_adapter(uint8_t type, uint8_t isc, bool swap,
> +                            bool maskable, uint32_t *id);
>   #endif
> diff --git a/hw/s390x/virtio-ccw.c b/hw/s390x/virtio-ccw.c
> index 2bf0af8..1193682 100644
> --- a/hw/s390x/virtio-ccw.c
> +++ b/hw/s390x/virtio-ccw.c
> @@ -522,6 +522,10 @@ static int virtio_ccw_cb(SubchDev *sch, CCW1 ccw)
>                   dev->thinint_isc = thinint->isc;
>                   dev->ind_bit = thinint->ind_bit;
>                   cpu_physical_memory_unmap(thinint, hw_len, 0, hw_len);
> +                ret = css_register_io_adapter(CSS_IO_ADAPTER_VIRTIO,
> +                                              dev->thinint_isc, true, false,
> +                                              &dev->adapter_id);

In all other machines the machine file is the one creating the link 
between a device and the interrupt controller. Can we do something 
similar for s390?


Alex