From: Christian Borntraeger <borntraeger@xxxxxxxxxx>
While we will not implement interception for query functions yet, we can
and should disable functions that have a control bit based on the given
CPU model.
Let us start with enabling the subfunction interface.
Signed-off-by: Christian Borntraeger <borntraeger@xxxxxxxxxx>
Reviewed-by: David Hildenbrand <david@xxxxxxxxxx>
Reviewed-by: Janosch Frank <frankja@xxxxxxxxxxxxxxxxxx>
Reviewed-by: Cornelia Huck <cohuck@xxxxxxxxxx>
---
arch/s390/include/asm/kvm_host.h | 1 +
arch/s390/kvm/kvm-s390.c | 35 ++++++++++++++++++++++-------------
2 files changed, 23 insertions(+), 13 deletions(-)
diff --git a/arch/s390/include/asm/kvm_host.h b/arch/s390/include/asm/kvm_host.h
index c5f5156..3369677 100644
--- a/arch/s390/include/asm/kvm_host.h
+++ b/arch/s390/include/asm/kvm_host.h
@@ -711,6 +711,7 @@ struct s390_io_adapter {
struct kvm_s390_cpu_model {
/* facility mask supported by kvm & hosting machine */
__u64 fac_mask[S390_ARCH_FAC_LIST_SIZE_U64];
+ struct kvm_s390_vm_cpu_subfunc subfuncs;
/* facility list requested by guest (in dma page) */
__u64 *fac_list;
u64 cpuid;
diff --git a/arch/s390/kvm/kvm-s390.c b/arch/s390/kvm/kvm-s390.c
index 2e47c72..82a95af 100644
--- a/arch/s390/kvm/kvm-s390.c
+++ b/arch/s390/kvm/kvm-s390.c
@@ -1266,11 +1266,20 @@ static int kvm_s390_set_processor_feat(struct kvm *kvm,
static int kvm_s390_set_processor_subfunc(struct kvm *kvm,
struct kvm_device_attr *attr)
{
- /*
- * Once supported by kernel + hw, we have to store the subfunctions
- * in kvm->arch and remember that user space configured them.
- */
- return -ENXIO;
+ mutex_lock(&kvm->lock);
+ if (kvm->created_vcpus) {
+ mutex_unlock(&kvm->lock);
+ return -EBUSY;
+ }
+
+ if (copy_from_user(&kvm->arch.model.subfuncs, (void __user *)attr->addr,
+ sizeof(struct kvm_s390_vm_cpu_subfunc))) {
+ mutex_unlock(&kvm->lock);
+ return -EFAULT;
+ }
+ mutex_unlock(&kvm->lock);
+
+ return 0;
}
static int kvm_s390_set_cpu_model(struct kvm *kvm, struct kvm_device_attr *attr)
@@ -1389,12 +1398,11 @@ static int kvm_s390_get_machine_feat(struct kvm *kvm,
static int kvm_s390_get_processor_subfunc(struct kvm *kvm,
struct kvm_device_attr *attr)
{
- /*
- * Once we can actually configure subfunctions (kernel + hw support),
- * we have to check if they were already set by user space, if so copy
- * them from kvm->arch.
- */
- return -ENXIO;
+ if (copy_to_user((void __user *)attr->addr, &kvm->arch.model.subfuncs,
+ sizeof(struct kvm_s390_vm_cpu_subfunc)))
+ return -EFAULT;
+
+ return 0;
}
static int kvm_s390_get_machine_subfunc(struct kvm *kvm,
@@ -1405,6 +1413,7 @@ static int kvm_s390_get_machine_subfunc(struct kvm *kvm,
return -EFAULT;
return 0;
}
+
static int kvm_s390_get_cpu_model(struct kvm *kvm, struct kvm_device_attr *attr)
{
int ret = -ENXIO;
@@ -1522,10 +1531,9 @@ static int kvm_s390_vm_has_attr(struct kvm *kvm, struct kvm_device_attr *attr)
case KVM_S390_VM_CPU_PROCESSOR_FEAT:
case KVM_S390_VM_CPU_MACHINE_FEAT:
case KVM_S390_VM_CPU_MACHINE_SUBFUNC:
+ case KVM_S390_VM_CPU_PROCESSOR_SUBFUNC:
ret = 0;
break;
- /* configuring subfunctions is not supported yet */
- case KVM_S390_VM_CPU_PROCESSOR_SUBFUNC:
default:
ret = -ENXIO;
break;
@@ -2227,6 +2235,7 @@ int kvm_arch_init_vm(struct kvm *kvm, unsigned long type)
kvm->arch.model.fac_list[i] = S390_lowcore.stfle_fac_list[i] &
kvm_s390_fac_base[i];
}
+ kvm->arch.model.subfuncs = kvm_s390_available_subfunc;
/* we are always in czam mode - even on pre z14 machines */
set_kvm_facility(kvm->arch.model.fac_mask, 138);
--
2.7.4
