KVM: s390: provide CMMA attributes only if available
Let's not provide the device attribute for cmma enabling and clearing
if the hardware doesn't support it.
This also helps getting rid of the undocumented return value "-EINVAL"
in case CMMA is not available when trying to enable it.
Also properly document the meaning of -EINVAL for CMMA clearing.
Reviewed-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>
diff --git a/arch/s390/kvm/kvm-s390.c b/arch/s390/kvm/kvm-s390.c
index 005e664..f695c6e 100644
--- a/arch/s390/kvm/kvm-s390.c
+++ b/arch/s390/kvm/kvm-s390.c
@@ -485,7 +485,7 @@
unsigned int idx;
switch (attr->attr) {
case KVM_S390_VM_MEM_ENABLE_CMMA:
- ret = -EINVAL;
+ ret = -ENXIO;
if (!sclp.has_cmma)
break;
@@ -499,6 +499,9 @@
mutex_unlock(&kvm->lock);
break;
case KVM_S390_VM_MEM_CLR_CMMA:
+ ret = -ENXIO;
+ if (!sclp.has_cmma)
+ break;
ret = -EINVAL;
if (!kvm->arch.use_cmma)
break;
@@ -964,6 +967,8 @@
switch (attr->attr) {
case KVM_S390_VM_MEM_ENABLE_CMMA:
case KVM_S390_VM_MEM_CLR_CMMA:
+ ret = sclp.has_cmma ? 0 : -ENXIO;
+ break;
case KVM_S390_VM_MEM_LIMIT_SIZE:
ret = 0;
break;