[PATCH v4 19/36] KVM: s390: protvirt: handle secure guest prefix pages

[Christian Borntraeger <borntraeger@de.ibm.com>]

From: Janosch Frank <frankja@linux.ibm.com>

The SPX instruction is handled by the ultravisor. We do get a
notification intercept, though. Let us update our internal view.

In addition to that, when the guest prefix page is not secure, an
intercept 112 (0x70) is indicated. Let us make the prefix pages
secure again.

Signed-off-by: Janosch Frank <frankja@linux.ibm.com>
Reviewed-by: David Hildenbrand <david@redhat.com>
[borntraeger@de.ibm.com: patch merging, splitting, fixing]
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
---
 arch/s390/include/asm/kvm_host.h |  1 +
 arch/s390/kvm/intercept.c        | 18 ++++++++++++++++++
 2 files changed, 19 insertions(+)

diff --git a/arch/s390/include/asm/kvm_host.h b/arch/s390/include/asm/kvm_host.h
index aa945b101fff..0ea82152d2f7 100644
--- a/arch/s390/include/asm/kvm_host.h
+++ b/arch/s390/include/asm/kvm_host.h
@@ -225,6 +225,7 @@ struct kvm_s390_sie_block {
 #define ICPT_INT_ENABLE	0x64
 #define ICPT_PV_INSTR	0x68
 #define ICPT_PV_NOTIFY	0x6c
+#define ICPT_PV_PREF	0x70
 	__u8	icptcode;		/* 0x0050 */
 	__u8	icptstatus;		/* 0x0051 */
 	__u16	ihcpu;			/* 0x0052 */
diff --git a/arch/s390/kvm/intercept.c b/arch/s390/kvm/intercept.c
index 331e620dcfdf..b6b7d4b0e26c 100644
--- a/arch/s390/kvm/intercept.c
+++ b/arch/s390/kvm/intercept.c
@@ -451,6 +451,15 @@ static int handle_operexc(struct kvm_vcpu *vcpu)
 	return kvm_s390_inject_program_int(vcpu, PGM_OPERATION);
 }
 
+static int handle_pv_spx(struct kvm_vcpu *vcpu)
+{
+	u32 pref = *(u32 *)vcpu->arch.sie_block->sidad;
+
+	kvm_s390_set_prefix(vcpu, pref);
+	trace_kvm_s390_handle_prefix(vcpu, 1, pref);
+	return 0;
+}
+
 static int handle_pv_sclp(struct kvm_vcpu *vcpu)
 {
 	struct kvm_s390_float_interrupt *fi = &vcpu->kvm->arch.float_int;
@@ -477,6 +486,8 @@ static int handle_pv_sclp(struct kvm_vcpu *vcpu)
 
 static int handle_pv_notification(struct kvm_vcpu *vcpu)
 {
+	if (vcpu->arch.sie_block->ipa == 0xb210)
+		return handle_pv_spx(vcpu);
 	if (vcpu->arch.sie_block->ipa == 0xb220)
 		return handle_pv_sclp(vcpu);
 
@@ -534,6 +545,13 @@ int kvm_handle_sie_intercept(struct kvm_vcpu *vcpu)
 	case ICPT_PV_NOTIFY:
 		rc = handle_pv_notification(vcpu);
 		break;
+	case ICPT_PV_PREF:
+		rc = 0;
+		gmap_convert_to_secure(vcpu->arch.gmap,
+				       kvm_s390_get_prefix(vcpu));
+		gmap_convert_to_secure(vcpu->arch.gmap,
+				       kvm_s390_get_prefix(vcpu) + PAGE_SIZE);
+		break;
 	default:
 		return -EOPNOTSUPP;
 	}
-- 
2.25.0