[PATCH v4 4/5] s390x: CPU topology: CPU topology migration

[Pierre Morel]

Both source and target must have the same configuration
regarding the activation of Perform Topology Function
and Store Topology System Information.

Signed-off-by: Pierre Morel <pmorel@linux.ibm.com>
---
 target/s390x/cpu.h                  |  2 ++
 target/s390x/cpu_features_def.h.inc |  1 +
 target/s390x/cpu_models.c           |  2 ++
 target/s390x/gen-features.c         |  3 ++
 target/s390x/kvm/kvm.c              |  6 ++++
 target/s390x/machine.c              | 48 +++++++++++++++++++++++++++++
 6 files changed, 62 insertions(+)

diff --git a/target/s390x/cpu.h b/target/s390x/cpu.h
index de05cc48cc..e3ca549774 100644
--- a/target/s390x/cpu.h
+++ b/target/s390x/cpu.h
@@ -150,6 +150,8 @@ struct CPUS390XState {
     /* currently processed sigp order */
     uint8_t sigp_order;
 
+    /* Using Perform CPU Topology Function*/
+    bool using_ptf;
 };
 
 static inline uint64_t *get_freg(CPUS390XState *cs, int nr)
diff --git a/target/s390x/cpu_features_def.h.inc 
b/target/s390x/cpu_features_def.h.inc
index e86662bb3b..27e8904978 100644
--- a/target/s390x/cpu_features_def.h.inc
+++ b/target/s390x/cpu_features_def.h.inc
@@ -146,6 +146,7 @@ DEF_FEAT(SIE_CEI, "cei", SCLP_CPU, 43, "SIE: 
Conditional-external-interception f
 DEF_FEAT(DAT_ENH_2, "dateh2", MISC, 0, "DAT-enhancement facility 2")
 DEF_FEAT(CMM, "cmm", MISC, 0, "Collaborative-memory-management facility")
 DEF_FEAT(AP, "ap", MISC, 0, "AP instructions installed")
+DEF_FEAT(CPU_TOPOLOGY, "cpu_topology", MISC, 0, "CPU Topology available")
 
 /* Features exposed via the PLO instruction. */
 DEF_FEAT(PLO_CL, "plo-cl", PLO, 0, "PLO Compare and load (32 bit in general 
registers)")
diff --git a/target/s390x/cpu_models.c b/target/s390x/cpu_models.c
index 11e06cc51f..1f9ea6479d 100644
--- a/target/s390x/cpu_models.c
+++ b/target/s390x/cpu_models.c
@@ -238,6 +238,7 @@ bool s390_has_feat(S390Feat feat)
 
     if (s390_is_pv()) {
         switch (feat) {
+        case S390_FEAT_CPU_TOPOLOGY:
         case S390_FEAT_DIAG_318:
         case S390_FEAT_HPMA2:
         case S390_FEAT_SIE_F2:
@@ -467,6 +468,7 @@ static void check_consistency(const S390CPUModel *model)
         { S390_FEAT_DIAG_318, S390_FEAT_EXTENDED_LENGTH_SCCB },
         { S390_FEAT_NNPA, S390_FEAT_VECTOR },
         { S390_FEAT_RDP, S390_FEAT_LOCAL_TLB_CLEARING },
+        { S390_FEAT_CPU_TOPOLOGY, S390_FEAT_CONFIGURATION_TOPOLOGY },
     };
     int i;
 
diff --git a/target/s390x/gen-features.c b/target/s390x/gen-features.c
index 7cb1a6ec10..377d8aad90 100644
--- a/target/s390x/gen-features.c
+++ b/target/s390x/gen-features.c
@@ -488,6 +488,7 @@ static uint16_t full_GEN9_GA3[] = {
 static uint16_t full_GEN10_GA1[] = {
     S390_FEAT_EDAT,
     S390_FEAT_CONFIGURATION_TOPOLOGY,
+    S390_FEAT_CPU_TOPOLOGY,
     S390_FEAT_GROUP_MSA_EXT_2,
     S390_FEAT_ESOP,
     S390_FEAT_SIE_PFMFI,
@@ -604,6 +605,8 @@ static uint16_t default_GEN9_GA1[] = {
 static uint16_t default_GEN10_GA1[] = {
     S390_FEAT_EDAT,
     S390_FEAT_GROUP_MSA_EXT_2,
+    S390_FEAT_CONFIGURATION_TOPOLOGY,
+    S390_FEAT_CPU_TOPOLOGY,
 };
 
 #define default_GEN10_GA2 EmptyFeat
diff --git a/target/s390x/kvm/kvm.c b/target/s390x/kvm/kvm.c
index c17e92fc9c..6ffc697b51 100644
--- a/target/s390x/kvm/kvm.c
+++ b/target/s390x/kvm/kvm.c
@@ -612,6 +612,7 @@ int kvm_arch_put_registers(CPUState *cs, int level)
     } else {
         /* prefix is only supported via sync regs */
     }
+
     return 0;
 }
 
@@ -2427,6 +2428,10 @@ void kvm_s390_get_host_cpu_model(S390CPUModel *model, 
Error **errp)
         clear_bit(S390_FEAT_CMM_NT, model->features);
     }
 
+    if (kvm_check_extension(kvm_state, KVM_CAP_S390_CPU_TOPOLOGY)) {
+        set_bit(S390_FEAT_CPU_TOPOLOGY, model->features);
+    }
+
     /* bpb needs kernel support for migration, VSIE and reset */
     if (!kvm_check_extension(kvm_state, KVM_CAP_S390_BPB)) {
         clear_bit(S390_FEAT_BPB, model->features);
@@ -2535,6 +2540,7 @@ void kvm_s390_apply_cpu_model(const S390CPUModel *model, 
Error **errp)
         error_setg(errp, "KVM: Error configuring CPU subfunctions: %d", rc);
         return;
     }
+
     /* enable CMM via CMMA */
     if (test_bit(S390_FEAT_CMM, model->features)) {
         kvm_s390_enable_cmma();
diff --git a/target/s390x/machine.c b/target/s390x/machine.c
index 37a076858c..6036e8e856 100644
--- a/target/s390x/machine.c
+++ b/target/s390x/machine.c
@@ -250,6 +250,53 @@ const VMStateDescription vmstate_diag318 = {
     }
 };
 
+static int cpu_topology_presave(void *opaque)
+{
+    S390CPU *cpu = opaque;
+
+    cpu->env.using_ptf = s390_has_feat(S390_FEAT_CPU_TOPOLOGY);
+    return 0;
+}
+
+static int cpu_topology_postload(void *opaque, int version_id)
+{
+    S390CPU *cpu = opaque;
+
+    if ((cpu->env.using_ptf == s390_has_feat(S390_FEAT_CPU_TOPOLOGY)) &&
+        (cpu->env.using_ptf == 
s390_has_feat(S390_FEAT_CONFIGURATION_TOPOLOGY))) {
+        return 0;
+    }
+    if (cpu->env.using_ptf) {
+        error_report("Target needs CPU Topology enabled");
+    } else {
+        if (s390_has_feat(S390_FEAT_CONFIGURATION_TOPOLOGY)) {
+            error_report("Target is not allowed to enable configuration 
Topology");
+        }
+        if (s390_has_feat(S390_FEAT_CPU_TOPOLOGY)) {
+            error_report("Target is not allowed to enable CPU Topology");
+        }
+    }
+    return -EINVAL;
+}
+
+static bool cpu_topology_needed(void *opaque)
+{
+    return 1;
+}
+
+const VMStateDescription vmstate_cpu_topology = {
+    .name = "cpu/cpu_topology",
+    .version_id = 1,
+    .pre_save = cpu_topology_presave,
+    .post_load = cpu_topology_postload,
+    .minimum_version_id = 1,
+    .needed = cpu_topology_needed,
+    .fields = (VMStateField[]) {
+        VMSTATE_BOOL(env.using_ptf, S390CPU),
+        VMSTATE_END_OF_LIST()
+    }
+};
+
 const VMStateDescription vmstate_s390_cpu = {
     .name = "cpu",
     .post_load = cpu_post_load,
@@ -287,6 +334,7 @@ const VMStateDescription vmstate_s390_cpu = {
         &vmstate_bpbc,
         &vmstate_etoken,
         &vmstate_diag318,
+        &vmstate_cpu_topology,
         NULL
     },
 };
-- 
2.27.0