KVM: s390: protvirt: Add program exception injection

Only two program exceptions can be injected for a protected guest:
specification and operand.

For both, a code needs to be specified in the interrupt injection
control of the state description, as the guest prefix page is not
accessible to KVM for such guests.
Signed-off-by: Janosch Frank <frankja@linux.ibm.com>
Reviewed-by: Cornelia Huck <cohuck@redhat.com>
Reviewed-by: Thomas Huth <thuth@redhat.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/kvm/interrupt.c

@@ -836,6 +836,21 @@ static int __must_check __deliver_external_call(struct kvm_vcpu *vcpu)
 	return rc ? -EFAULT : 0;
 }
 
+static int __deliver_prog_pv(struct kvm_vcpu *vcpu, u16 code)
+{
+	switch (code) {
+	case PGM_SPECIFICATION:
+		vcpu->arch.sie_block->iictl = IICTL_CODE_SPECIFICATION;
+		break;
+	case PGM_OPERAND:
+		vcpu->arch.sie_block->iictl = IICTL_CODE_OPERAND;
+		break;
+	default:
+		return -EINVAL;
+	}
+	return 0;
+}
+
 static int __must_check __deliver_prog(struct kvm_vcpu *vcpu)
 {
 	struct kvm_s390_local_interrupt *li = &vcpu->arch.local_int;
@@ -856,6 +871,10 @@ static int __must_check __deliver_prog(struct kvm_vcpu *vcpu)
 	trace_kvm_s390_deliver_interrupt(vcpu->vcpu_id, KVM_S390_PROGRAM_INT,
 					 pgm_info.code, 0);
 
+	/* PER is handled by the ultravisor */
+	if (kvm_s390_pv_cpu_is_protected(vcpu))
+		return __deliver_prog_pv(vcpu, pgm_info.code & ~PGM_PER);
+
 	switch (pgm_info.code & ~PGM_PER) {
 	case PGM_AFX_TRANSLATION:
 	case PGM_ASX_TRANSLATION: