KVM: s390: vsie: support IBS interpretation

We can easily enable ibs for guest 2, so he can use it for guest 3.
Acked-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>

arch/s390/include/uapi/asm/kvm.h

@@ -105,6 +105,7 @@ struct kvm_s390_vm_cpu_machine {
 #define KVM_S390_VM_CPU_FEAT_GSLS	5
 #define KVM_S390_VM_CPU_FEAT_IB		6
 #define KVM_S390_VM_CPU_FEAT_CEI	7
+#define KVM_S390_VM_CPU_FEAT_IBS	8
 struct kvm_s390_vm_cpu_feat {
 	__u64 feat[16];
 };

arch/s390/kvm/kvm-s390.c

@@ -277,6 +277,8 @@ static void kvm_s390_cpu_feat_init(void)
 		allow_cpu_feat(KVM_S390_VM_CPU_FEAT_IB);
 	if (sclp.has_cei)
 		allow_cpu_feat(KVM_S390_VM_CPU_FEAT_CEI);
+	if (sclp.has_ibs)
+		allow_cpu_feat(KVM_S390_VM_CPU_FEAT_IBS);
 }
 
 int kvm_arch_init(void *opaque)

arch/s390/kvm/vsie.c

@@ -111,6 +111,8 @@ static int prepare_cpuflags(struct kvm_vcpu *vcpu, struct vsie_page *vsie_page)
 		newflags |= cpuflags & CPUSTAT_P;
 	if (test_kvm_cpu_feat(vcpu->kvm, KVM_S390_VM_CPU_FEAT_GSLS))
 		newflags |= cpuflags & CPUSTAT_SM;
+	if (test_kvm_cpu_feat(vcpu->kvm, KVM_S390_VM_CPU_FEAT_IBS))
+		newflags |= cpuflags & CPUSTAT_IBS;
 
 	atomic_set(&scb_s->cpuflags, newflags);
 	return 0;