s390x/cpumodel: let the CPU model handle feature checks

If we have certain features enabled, we have to migrate additional state
(e.g. vector registers or runtime-instrumentation registers). Let the
CPU model control that unless we have no "host" CPU model in the KVM
case. This will later on be the case for compatibility machines, so
migration from QEMU versions without the CPU model will still work.

Acked-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Message-Id: <20160905085244.99980-12-dahi@linux.vnet.ibm.com>
Signed-off-by: Cornelia Huck <cornelia.huck@de.ibm.com>

1 files changed, 25 insertions, 0 deletions

diff --git a/target-s390x/cpu_models.c b/target-s390x/cpu_models.c
index 57e3bd0a59..3545bad4d6 100644
--- a/target-s390x/cpu_models.c
+++ b/target-s390x/cpu_models.c
@@ -73,6 +73,31 @@ static S390CPUDef s390_cpu_defs[] = {
     CPUDEF_INIT(0x2965, 13, 2, 47, 0x08000000U, "z13s", "IBM z13s GA1"),
 };
 
+bool s390_has_feat(S390Feat feat)
+{
+    static S390CPU *cpu;
+
+    if (!cpu) {
+        cpu = S390_CPU(qemu_get_cpu(0));
+    }
+
+    if (!cpu || !cpu->model) {
+#ifdef CONFIG_KVM
+        if (kvm_enabled()) {
+            if (feat == S390_FEAT_VECTOR) {
+                return kvm_check_extension(kvm_state,
+                                           KVM_CAP_S390_VECTOR_REGISTERS);
+            }
+            if (feat == S390_FEAT_RUNTIME_INSTRUMENTATION) {
+                return kvm_s390_get_ri();
+            }
+        }
+#endif
+        return 0;
+    }
+    return test_bit(feat, cpu->model->features);
+}
+
 struct S390PrintCpuListInfo {
     FILE *f;
     fprintf_function print;