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

[Shalini Chellathurai Saroja <shalini@linux.ibm.com>]

On 2025-06-17 19:09, Nina Schoetterl-Glausch wrote:
> 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>

Hello Nina,

Thank you very much for the quick review.

-- 
Mit freundlichen Grüßen / Kind regards
Shalini Chellathurai Saroja
Software Developer
Linux on IBM Z & KVM Development
IBM Deutschland Research & Development GmbH
Dept 1419, Schoenaicher Str. 220, 71032 Boeblingen
Vorsitzender des Aufsichtsrats: Wolfgang Wendt
Geschäftsführung: David Faller
Sitz der Gesellschaft: Böblingen / Registergericht: Amtsgericht 
Stuttgart, HRB 243294