Re: [PATCH v6 2/3] hw/s390x: add Control-Program Identification to QOM

[Nina Schoetterl-Glausch <nsg@linux.ibm.com>]

On Mon, 2025-06-16 at 16:01 +0200, Shalini Chellathurai Saroja wrote:
> Add Control-Program Identification (CPI) data to the QEMU Object
> Model (QOM), along with the timestamp in which the data was received
> as shown below.
> 
> virsh # qemu-monitor-command vm --pretty '{"execute":"qom-list",
> "arguments":{"path":"/machine/sclp/s390-sclp-event-facility/sclpcpi"}}'
> {
>   "return": [
>     [...]
>     {
>       "name": "system_level",
>       "type": "uint64"
>     },
>     {
>       "name": "system_name",
>       "type": "string"
>     },
>     {
>       "name": "system_type",
>       "type": "string"
>     },
>     {
>       "name": "timestamp",
>       "type": "uint64"
>     },
>     {
>       "name": "sysplex_name",
>       "type": "string"
>     }
>   ],
>   "id": "libvirt-14"
> }
> 
> Example CPI data:
> virsh # qemu-monitor-command vm --pretty '{"execute":"qom-get",
> "arguments":{"path":"/machine/sclp/s390-sclp-event-facility/sclpcpi",
> "property":"system_type"}}'
> {
>   "return": "LINUX   ",
>   "id": "libvirt-18"
> }
> virsh # qemu-monitor-command vm --pretty '{"execute":"qom-get",
> "arguments":{"path":"/machine/sclp/s390-sclp-event-facility/sclpcpi",
> "property":"system_name"}}'
> {
>   "return": "TESTVM  ",
>   "id": "libvirt-19"
> }
> virsh # qemu-monitor-command vm --pretty '{"execute":"qom-get",
> "arguments":{"path":"/machine/sclp/s390-sclp-event-facility/sclpcpi",
> "property":"sysplex_name"}}'
> {
>   "return": "PLEX    ",
>   "id": "libvirt-20"
> }
> virsh # qemu-monitor-command vm --pretty '{"execute":"qom-get",
> "arguments":{"path":"/machine/sclp/s390-sclp-event-facility/sclpcpi",
> "property":"system_level"}}'
> {
>   "return": 74872343805430528,
>   "id": "libvirt-21"
> }
> virsh # qemu-monitor-command vm --pretty '{"execute":"qom-get",
> "arguments":{"path":"/machine/sclp/s390-sclp-event-facility/sclpcpi",
> "property":"timestamp"}}'
> {
>   "return": 1748866753433923000,
>   "id": "libvirt-22"
> }
> 
> Signed-off-by: Shalini Chellathurai Saroja <shalini@linux.ibm.com>
> ---
>  hw/s390x/sclpcpi.c                | 74 +++++++++++++++++++++++++++++++
>  include/hw/s390x/event-facility.h |  5 +++
>  2 files changed, 79 insertions(+)
> 
> diff --git a/hw/s390x/sclpcpi.c b/hw/s390x/sclpcpi.c
> index a0b175c5d5..352ef0461d 100644
> --- a/hw/s390x/sclpcpi.c
> +++ b/hw/s390x/sclpcpi.c
> @@ -50,7 +50,10 @@
>    */
>  
>  #include "qemu/osdep.h"
> +#include "qemu/timer.h"
>  #include "hw/s390x/event-facility.h"
> +#include "hw/s390x/ebcdic.h"
> +#include "qapi/qapi-visit-machine.h"
>  
>  typedef struct Data {
>      uint8_t id_format;
> @@ -90,11 +93,58 @@ static int write_event_data(SCLPEvent *event, EventBufferHeader *evt_buf_hdr)
>  {
>      ControlProgramIdMsg *cpim = container_of(evt_buf_hdr, ControlProgramIdMsg,
>                                               ebh);
> +    SCLPEventCPI *e = SCLP_EVENT_CPI(event);
> +
> +    ascii_put(e->system_type, (char *)cpim->data.system_type,
> +              sizeof(cpim->data.system_type));
> +    ascii_put(e->system_name, (char *)cpim->data.system_name,
> +              sizeof(cpim->data.system_name));
> +    ascii_put(e->sysplex_name, (char *)cpim->data.sysplex_name,
> +              sizeof(cpim->data.sysplex_name));
> +    e->system_level = ldq_be_p(&cpim->data.system_level);
> +    e->timestamp = qemu_clock_get_ns(QEMU_CLOCK_HOST);
>  
>      cpim->ebh.flags = SCLP_EVENT_BUFFER_ACCEPTED;
>      return SCLP_RC_NORMAL_COMPLETION;
>  }
>  
> +static char *get_system_type(Object *obj, Error **errp)
> +{
> +    SCLPEventCPI *e = SCLP_EVENT_CPI(obj);
> +
> +    return g_strndup((char *) e->system_type, sizeof(e->system_type));
> +}
> +
> +static char *get_system_name(Object *obj, Error **errp)
> +{
> +    SCLPEventCPI *e = SCLP_EVENT_CPI(obj);
> +
> +    return g_strndup((char *) e->system_name, sizeof(e->system_name));
> +}
> +
> +static char *get_sysplex_name(Object *obj, Error **errp)
> +{
> +    SCLPEventCPI *e = SCLP_EVENT_CPI(obj);
> +
> +    return g_strndup((char *) e->sysplex_name, sizeof(e->sysplex_name));
> +}
> +
> +static void get_system_level(Object *obj, Visitor *v, const char *name,
> +                             void *opaque, Error **errp)
> +{
> +    SCLPEventCPI *e = SCLP_EVENT_CPI(obj);
> +
> +    visit_type_uint64(v, name, &e->system_level, errp);
> +}
> +
> +static void get_timestamp(Object *obj, Visitor *v, const char *name,
> +                             void *opaque, Error **errp)
> +{
> +    SCLPEventCPI *e = SCLP_EVENT_CPI(obj);
> +
> +    visit_type_uint64(v, name, &e->timestamp, errp);
> +}
> +
>  static void cpi_class_init(ObjectClass *klass, const void *data)
>  {
>      DeviceClass *dc = DEVICE_CLASS(klass);
> @@ -106,6 +156,30 @@ static void cpi_class_init(ObjectClass *klass, const void *data)
>      k->get_send_mask = send_mask;
>      k->get_receive_mask = receive_mask;
>      k->write_event_data = write_event_data;
> +
> +    object_class_property_add_str(klass, "system_type", get_system_type, NULL);
> +    object_class_property_set_description(klass, "system_type",
> +            "operating system e.g. \"LINUX   \"");
> +
> +    object_class_property_add_str(klass, "system_name", get_system_name, NULL);
> +    object_class_property_set_description(klass, "system_name",
> +            "user configurable name of the VM e.g. \"TESTVM  \"");
> +
> +    object_class_property_add_str(klass, "sysplex_name", get_sysplex_name,
> +                                  NULL);
> +    object_class_property_set_description(klass, "sysplex_name",
> +            "name of the cluster which the VM belongs to, if any"
> +            " e.g. \"PLEX    \"");
> +
> +    object_class_property_add(klass, "system_level", "uint64", get_system_level,
> +                              NULL, NULL, NULL);
> +    object_class_property_set_description(klass, "system_level",
> +            "distribution and kernel version in Linux e.g. 74872343805430528");
> +
> +    object_class_property_add(klass, "timestamp", "uint64", get_timestamp,
> +                              NULL, NULL, NULL);
> +    object_class_property_set_description(klass, "timestamp",
> +            "latest update of CPI data in nanoseconds since the UNIX EPOCH");
>  }
>  
>  static const TypeInfo sclp_cpi_info = {
> diff --git a/include/hw/s390x/event-facility.h b/include/hw/s390x/event-facility.h
> index e81bc80498..eac7a51100 100644
> --- a/include/hw/s390x/event-facility.h
> +++ b/include/hw/s390x/event-facility.h
> @@ -201,6 +201,11 @@ OBJECT_DECLARE_TYPE(SCLPEventCPI, SCLPEventCPIClass,
>  
>  struct SCLPEventCPI {
>      SCLPEvent event;
> +    uint8_t system_type[8];
> +    uint8_t system_name[8];
> +    uint64_t system_level;
> +    uint8_t sysplex_name[8];
> +    uint64_t timestamp;
>  };
>  
>  #define TYPE_SCLP_EVENT_FACILITY "s390-sclp-event-facility"

Might want to make the uint8_ts into chars since it's ascii, but not important.
Reviewed-by: Nina Schoetterl-Glausch <nsg@linux.ibm.com>


-- 
IBM Deutschland Research & Development GmbH
Vorsitzender des Aufsichtsrats: Wolfgang Wendt
Geschäftsführung: David Faller
Sitz der Gesellschaft: Böblingen / Registergericht: Amtsgericht Stuttgart, HRB 243294