[Qemu-devel] [PATCH RFC 06/11] s390/qemu: cpu model KVM properties requests

[Michael Mueller]

This patch implements the functions s390_fetch_kvm_host_props() and
s390_request_kvm_cpu_config(). They respectively retrieve or request
the machine type, cpu facilities and KVM facility mask supported by
the host. Both functions are based on the s390 configuration device
interface.

Signed-off-by: Michael Mueller <address@hidden>
---
 target-s390x/cpu-models.c | 65 +++++++++++++++++++++++++++++++++++++++++++++++
 target-s390x/cpu-models.h | 16 ++++++++++++
 2 files changed, 81 insertions(+)

diff --git a/target-s390x/cpu-models.c b/target-s390x/cpu-models.c
index 4a4720a..4ce1546 100644
--- a/target-s390x/cpu-models.c
+++ b/target-s390x/cpu-models.c
@@ -234,6 +234,71 @@ static int set_s390_cpu_alias(const char *name, const char 
*model)
         return 0;
 }
 
+/* return host specific properties */
+int s390_fetch_kvm_host_props(struct S390HostProps *prop)
+{
+    int ret;
+
+    ret = get_s390_config_attr(KVM_DEV_S390_CONFIG_CPU_TYPE,
+                               &prop->vcpu.type);
+    if (ret) {
+        return ret;
+    }
+    ret = get_s390_config_attr(KVM_DEV_S390_CONFIG_CPU_FACILITIES,
+                               &prop->vcpu.facilities);
+    if (ret) {
+        return ret;
+    }
+
+    ret = get_s390_config_attr(KVM_DEV_S390_CONFIG_KVM_FACILITY_MASK,
+                               &prop->host.facility_mask);
+    if (ret) {
+        return ret;
+    }
+
+    return 0;
+}
+
+/* request cpu configuration defined in S390 cpu class */
+int s390_request_kvm_cpu_config(S390CPUClass *cc)
+{
+    int ret = 0;
+
+    {
+        struct kvm_s390_attr_cpu_type cpu;
+        ret = set_s390_config_attr(KVM_DEV_S390_CONFIG_CPU_TYPE, &cc->type);
+        if (ret) {
+            goto out;
+        }
+        ret = get_s390_config_attr(KVM_DEV_S390_CONFIG_CPU_TYPE, &cpu.type);
+        if (ret) {
+            goto out;
+        }
+        if (cc->type != cpu.type) {
+            goto out;
+        }
+    }
+    {
+        struct kvm_s390_attr_cpu_facilities cpu;
+        int i;
+        ret = set_s390_config_attr(KVM_DEV_S390_CONFIG_CPU_FACILITIES, 
cc->kvm_facilities);
+        if (ret) {
+            goto out;
+        }
+        ret = get_s390_config_attr(KVM_DEV_S390_CONFIG_CPU_FACILITIES, 
&cpu.facilities);
+        if (ret) {
+            goto out;
+        }
+        for (i = 0; i < sizeof(cpu.facilities) / sizeof(unsigned long); i++) {
+            if (cc->kvm_facilities[i] != cpu.facilities[i]) {
+                goto out;
+            }
+        }
+    }
+out:
+    return ret;
+}
+
 /* define S390 CPU model classes */
 S390_PROC_DEF("2064-ga1", CPU_S390_2064_GA1, "IBM zSeries 900 GA1")
 S390_PROC_DEF("2064-ga2", CPU_S390_2064_GA2, "IBM zSeries 900 GA2")
diff --git a/target-s390x/cpu-models.h b/target-s390x/cpu-models.h
index e188eca..0789a5e 100644
--- a/target-s390x/cpu-models.h
+++ b/target-s390x/cpu-models.h
@@ -34,6 +34,22 @@ typedef struct S390CPUAlias {
 } S390CPUAlias;
 extern GSList *s390_cpu_aliases;
 
+/*
+ * host system properties used to trim s390
+ * cpu class attributes during initial kvm setup
+ */
+struct S390HostProps {
+    struct {
+        unsigned long  facility_mask[256];
+    } host;
+    struct {
+        unsigned short type;
+        unsigned long  facilities[256];
+    } vcpu;
+};
+
+int s390_fetch_kvm_host_props(struct S390HostProps *prop);
+int s390_request_kvm_cpu_config(S390CPUClass *cc);
 ObjectClass *s390_cpu_class_by_name(const char *name);
 
 /*
-- 
1.8.3.1