3 files changed, 113 insertions, 0 deletions

diff --git a/arch/s390/kvm/kvm-s390.c b/arch/s390/kvm/kvm-s390.c
index af09d3437631..e65b7637cc45 100644
--- a/arch/s390/kvm/kvm-s390.c
+++ b/arch/s390/kvm/kvm-s390.c
@@ -130,6 +130,12 @@ struct kvm_stats_debugfs_item debugfs_entries[] = {
 	{ NULL }
 };
 
+struct kvm_s390_tod_clock_ext {
+	__u8 epoch_idx;
+	__u64 tod;
+	__u8 reserved[7];
+} __packed;
+
 /* allow nested virtualization in KVM (if enabled by user space) */
 static int nested;
 module_param(nested, int, S_IRUGO);
@@ -874,6 +880,26 @@ static int kvm_s390_vm_get_migration(struct kvm *kvm,
 	return 0;
 }
 
+static int kvm_s390_set_tod_ext(struct kvm *kvm, struct kvm_device_attr *attr)
+{
+	struct kvm_s390_vm_tod_clock gtod;
+
+	if (copy_from_user(&gtod, (void __user *)attr->addr, sizeof(gtod)))
+		return -EFAULT;
+
+	if (test_kvm_facility(kvm, 139))
+		kvm_s390_set_tod_clock_ext(kvm, &gtod);
+	else if (gtod.epoch_idx == 0)
+		kvm_s390_set_tod_clock(kvm, gtod.tod);
+	else
+		return -EINVAL;
+
+	VM_EVENT(kvm, 3, "SET: TOD extension: 0x%x, TOD base: 0x%llx",
+		gtod.epoch_idx, gtod.tod);
+
+	return 0;
+}
+
 static int kvm_s390_set_tod_high(struct kvm *kvm, struct kvm_device_attr *attr)
 {
 	u8 gtod_high;
@@ -909,6 +935,9 @@ static int kvm_s390_set_tod(struct kvm *kvm, struct kvm_device_attr *attr)
 		return -EINVAL;
 
 	switch (attr->attr) {
+	case KVM_S390_VM_TOD_EXT:
+		ret = kvm_s390_set_tod_ext(kvm, attr);
+		break;
 	case KVM_S390_VM_TOD_HIGH:
 		ret = kvm_s390_set_tod_high(kvm, attr);
 		break;
@@ -922,6 +951,43 @@ static int kvm_s390_set_tod(struct kvm *kvm, struct kvm_device_attr *attr)
 	return ret;
 }
 
+static void kvm_s390_get_tod_clock_ext(struct kvm *kvm,
+					struct kvm_s390_vm_tod_clock *gtod)
+{
+	struct kvm_s390_tod_clock_ext htod;
+
+	preempt_disable();
+
+	get_tod_clock_ext((char *)&htod);
+
+	gtod->tod = htod.tod + kvm->arch.epoch;
+	gtod->epoch_idx = htod.epoch_idx + kvm->arch.epdx;
+
+	if (gtod->tod < htod.tod)
+		gtod->epoch_idx += 1;
+
+	preempt_enable();
+}
+
+static int kvm_s390_get_tod_ext(struct kvm *kvm, struct kvm_device_attr *attr)
+{
+	struct kvm_s390_vm_tod_clock gtod;
+
+	memset(&gtod, 0, sizeof(gtod));
+
+	if (test_kvm_facility(kvm, 139))
+		kvm_s390_get_tod_clock_ext(kvm, &gtod);
+	else
+		gtod.tod = kvm_s390_get_tod_clock_fast(kvm);
+
+	if (copy_to_user((void __user *)attr->addr, &gtod, sizeof(gtod)))
+		return -EFAULT;
+
+	VM_EVENT(kvm, 3, "QUERY: TOD extension: 0x%x, TOD base: 0x%llx",
+		gtod.epoch_idx, gtod.tod);
+	return 0;
+}
+
 static int kvm_s390_get_tod_high(struct kvm *kvm, struct kvm_device_attr *attr)
 {
 	u8 gtod_high = 0;
@@ -954,6 +1020,9 @@ static int kvm_s390_get_tod(struct kvm *kvm, struct kvm_device_attr *attr)
 		return -EINVAL;
 
 	switch (attr->attr) {
+	case KVM_S390_VM_TOD_EXT:
+		ret = kvm_s390_get_tod_ext(kvm, attr);
+		break;
 	case KVM_S390_VM_TOD_HIGH:
 		ret = kvm_s390_get_tod_high(kvm, attr);
 		break;
@@ -2369,6 +2438,9 @@ int kvm_arch_vcpu_setup(struct kvm_vcpu *vcpu)
 		vcpu->arch.sie_block->eca |= ECA_VX;
 		vcpu->arch.sie_block->ecd |= ECD_HOSTREGMGMT;
 	}
+	if (test_kvm_facility(vcpu->kvm, 139))
+		vcpu->arch.sie_block->ecd |= ECD_MEF;
+
 	vcpu->arch.sie_block->sdnxo = ((unsigned long) &vcpu->run->s.regs.sdnx)
 					| SDNXC;
 	vcpu->arch.sie_block->riccbd = (unsigned long) &vcpu->run->s.regs.riccb;
@@ -2855,6 +2927,35 @@ retry:
 	return 0;
 }
 
+void kvm_s390_set_tod_clock_ext(struct kvm *kvm,
+				 const struct kvm_s390_vm_tod_clock *gtod)
+{
+	struct kvm_vcpu *vcpu;
+	struct kvm_s390_tod_clock_ext htod;
+	int i;
+
+	mutex_lock(&kvm->lock);
+	preempt_disable();
+
+	get_tod_clock_ext((char *)&htod);
+
+	kvm->arch.epoch = gtod->tod - htod.tod;
+	kvm->arch.epdx = gtod->epoch_idx - htod.epoch_idx;
+
+	if (kvm->arch.epoch > gtod->tod)
+		kvm->arch.epdx -= 1;
+
+	kvm_s390_vcpu_block_all(kvm);
+	kvm_for_each_vcpu(i, vcpu, kvm) {
+		vcpu->arch.sie_block->epoch = kvm->arch.epoch;
+		vcpu->arch.sie_block->epdx  = kvm->arch.epdx;
+	}
+
+	kvm_s390_vcpu_unblock_all(kvm);
+	preempt_enable();
+	mutex_unlock(&kvm->lock);
+}
+
 void kvm_s390_set_tod_clock(struct kvm *kvm, u64 tod)
 {
 	struct kvm_vcpu *vcpu;
diff --git a/arch/s390/kvm/kvm-s390.h b/arch/s390/kvm/kvm-s390.h
index 6fedc8bc7a37..9f8fdd7b2311 100644
--- a/arch/s390/kvm/kvm-s390.h
+++ b/arch/s390/kvm/kvm-s390.h
@@ -272,6 +272,8 @@ int kvm_s390_handle_sigp_pei(struct kvm_vcpu *vcpu);
 int handle_sthyi(struct kvm_vcpu *vcpu);
 
 /* implemented in kvm-s390.c */
+void kvm_s390_set_tod_clock_ext(struct kvm *kvm,
+				 const struct kvm_s390_vm_tod_clock *gtod);
 void kvm_s390_set_tod_clock(struct kvm *kvm, u64 tod);
 long kvm_arch_fault_in_page(struct kvm_vcpu *vcpu, gpa_t gpa, int writable);
 int kvm_s390_store_status_unloaded(struct kvm_vcpu *vcpu, unsigned long addr);
diff --git a/arch/s390/kvm/vsie.c b/arch/s390/kvm/vsie.c
index 715c19c45d9a..d471910bd9ea 100644
--- a/arch/s390/kvm/vsie.c
+++ b/arch/s390/kvm/vsie.c
@@ -349,6 +349,9 @@ static int shadow_scb(struct kvm_vcpu *vcpu, struct vsie_page *vsie_page)
 		scb_s->eca |= scb_o->eca & ECA_IB;
 	if (test_kvm_cpu_feat(vcpu->kvm, KVM_S390_VM_CPU_FEAT_CEI))
 		scb_s->eca |= scb_o->eca & ECA_CEI;
+	/* Epoch Extension */
+	if (test_kvm_facility(vcpu->kvm, 139))
+		scb_s->ecd |= scb_o->ecd & ECD_MEF;
 
 	prepare_ibc(vcpu, vsie_page);
 	rc = shadow_crycb(vcpu, vsie_page);
@@ -919,6 +922,13 @@ static void register_shadow_scb(struct kvm_vcpu *vcpu,
 	 */
 	preempt_disable();
 	scb_s->epoch += vcpu->kvm->arch.epoch;
+
+	if (scb_s->ecd & ECD_MEF) {
+		scb_s->epdx += vcpu->kvm->arch.epdx;
+		if (scb_s->epoch < vcpu->kvm->arch.epoch)
+			scb_s->epdx += 1;
+	}
+
 	preempt_enable();
 }