On 20.02.20 11:40, Christian Borntraeger wrote: > From: Janosch Frank <frankja@xxxxxxxxxxxxx> > > That information, e.g. the maximum number of guests or installed > Ultravisor facilities, is interesting for QEMU, Libvirt and > administrators. > > Let's provide an easily parsable API to get that information. > > Signed-off-by: Janosch Frank <frankja@xxxxxxxxxxxxx> > --- > arch/s390/kernel/uv.c | 86 +++++++++++++++++++++++++++++++++++++++++++ > 1 file changed, 86 insertions(+) > > diff --git a/arch/s390/kernel/uv.c b/arch/s390/kernel/uv.c > index 4539003dac9d..550e9617c459 100644 > --- a/arch/s390/kernel/uv.c > +++ b/arch/s390/kernel/uv.c > @@ -323,5 +323,91 @@ int arch_make_page_accessible(struct page *page) > return rc; > } > EXPORT_SYMBOL_GPL(arch_make_page_accessible); > +#endif > + > +#if defined(CONFIG_PROTECTED_VIRTUALIZATION_GUEST) || IS_ENABLED(CONFIG_KVM) > +static ssize_t uv_query_facilities(struct kobject *kobj, > + struct kobj_attribute *attr, char *page) > +{ > + return snprintf(page, PAGE_SIZE, "%lx\n%lx\n%lx\n%lx\n", > + uv_info.inst_calls_list[0], > + uv_info.inst_calls_list[1], > + uv_info.inst_calls_list[2], > + uv_info.inst_calls_list[3]); > +} > + > +static struct kobj_attribute uv_query_facilities_attr = > + __ATTR(facilities, 0444, uv_query_facilities, NULL); > + > +static ssize_t uv_query_max_guest_cpus(struct kobject *kobj, > + struct kobj_attribute *attr, char *page) > +{ > + return snprintf(page, PAGE_SIZE, "%d\n", > + uv_info.max_guest_cpus); > +} > + > +static struct kobj_attribute uv_query_max_guest_cpus_attr = > + __ATTR(max_cpus, 0444, uv_query_max_guest_cpus, NULL); > + > +static ssize_t uv_query_max_guest_vms(struct kobject *kobj, > + struct kobj_attribute *attr, char *page) > +{ > + return snprintf(page, PAGE_SIZE, "%d\n", > + uv_info.max_num_sec_conf); > +} > + > +static struct kobj_attribute uv_query_max_guest_vms_attr = > + __ATTR(max_guests, 0444, uv_query_max_guest_vms, NULL); > + > +static ssize_t uv_query_max_guest_addr(struct kobject *kobj, > + struct kobj_attribute *attr, char *page) > +{ > + return snprintf(page, PAGE_SIZE, "%lx\n", > + uv_info.max_sec_stor_addr); > +} > + > +static struct kobj_attribute uv_query_max_guest_addr_attr = > + __ATTR(max_address, 0444, uv_query_max_guest_addr, NULL); > + > +static struct attribute *uv_query_attrs[] = { > + &uv_query_facilities_attr.attr, > + &uv_query_max_guest_cpus_attr.attr, > + &uv_query_max_guest_vms_attr.attr, > + &uv_query_max_guest_addr_attr.attr, > + NULL, > +}; > + > +static struct attribute_group uv_query_attr_group = { > + .attrs = uv_query_attrs, > +}; > > +static struct kset *uv_query_kset; > +struct kobject *uv_kobj; > + > +static int __init uv_info_init(void) > +{ > + int rc = -ENOMEM; > + > + if (!test_facility(158)) > + return 0; > + > + uv_kobj = kobject_create_and_add("uv", firmware_kobj); > + if (!uv_kobj) > + return -ENOMEM; > + > + uv_query_kset = kset_create_and_add("query", NULL, uv_kobj); > + if (!uv_query_kset) > + goto out_kobj; > + > + rc = sysfs_create_group(&uv_query_kset->kobj, &uv_query_attr_group); > + if (!rc) > + return 0; > + > + kset_unregister(uv_query_kset); > +out_kobj: > + kobject_del(uv_kobj); > + kobject_put(uv_kobj); > + return rc; > +} > +device_initcall(uv_info_init); > #endif > Reviewed-by: David Hildenbrand <david@xxxxxxxxxx> -- Thanks, David / dhildenb