KVM: s390: log capability enablement and vm attribute changes

Depending on user space, some capabilities and vm attributes are
enabled at runtime. Let's log those events and while we're at it,
log querying the vm attributes as well.

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 7621036..924b1ae 100644
--- a/arch/s390/kvm/kvm-s390.c
+++ b/arch/s390/kvm/kvm-s390.c
@@ -299,10 +299,12 @@
 
 	switch (cap->cap) {
 	case KVM_CAP_S390_IRQCHIP:
+		VM_EVENT(kvm, 3, "%s", "ENABLE: CAP_S390_IRQCHIP");
 		kvm->arch.use_irqchip = 1;
 		r = 0;
 		break;
 	case KVM_CAP_S390_USER_SIGP:
+		VM_EVENT(kvm, 3, "%s", "ENABLE: CAP_S390_USER_SIGP");
 		kvm->arch.user_sigp = 1;
 		r = 0;
 		break;
@@ -313,8 +315,11 @@
 			r = 0;
 		} else
 			r = -EINVAL;
+		VM_EVENT(kvm, 3, "ENABLE: CAP_S390_VECTOR_REGISTERS %s",
+			 r ? "(not available)" : "(success)");
 		break;
 	case KVM_CAP_S390_USER_STSI:
+		VM_EVENT(kvm, 3, "%s", "ENABLE: CAP_S390_USER_STSI");
 		kvm->arch.user_stsi = 1;
 		r = 0;
 		break;
@@ -332,6 +337,8 @@
 	switch (attr->attr) {
 	case KVM_S390_VM_MEM_LIMIT_SIZE:
 		ret = 0;
+		VM_EVENT(kvm, 3, "QUERY: max guest memory: %lu bytes",
+			 kvm->arch.gmap->asce_end);
 		if (put_user(kvm->arch.gmap->asce_end, (u64 __user *)attr->addr))
 			ret = -EFAULT;
 		break;
@@ -354,6 +361,7 @@
 			break;
 
 		ret = -EBUSY;
+		VM_EVENT(kvm, 3, "%s", "ENABLE: CMMA support");
 		mutex_lock(&kvm->lock);
 		if (atomic_read(&kvm->online_vcpus) == 0) {
 			kvm->arch.use_cmma = 1;
@@ -366,6 +374,7 @@
 		if (!kvm->arch.use_cmma)
 			break;
 
+		VM_EVENT(kvm, 3, "%s", "RESET: CMMA states");
 		mutex_lock(&kvm->lock);
 		idx = srcu_read_lock(&kvm->srcu);
 		s390_reset_cmma(kvm->arch.gmap->mm);
@@ -401,6 +410,7 @@
 			}
 		}
 		mutex_unlock(&kvm->lock);
+		VM_EVENT(kvm, 3, "SET: max guest memory: %lu bytes", new_limit);
 		break;
 	}
 	default:
@@ -427,22 +437,26 @@
 			kvm->arch.crypto.crycb->aes_wrapping_key_mask,
 			sizeof(kvm->arch.crypto.crycb->aes_wrapping_key_mask));
 		kvm->arch.crypto.aes_kw = 1;
+		VM_EVENT(kvm, 3, "%s", "ENABLE: AES keywrapping support");
 		break;
 	case KVM_S390_VM_CRYPTO_ENABLE_DEA_KW:
 		get_random_bytes(
 			kvm->arch.crypto.crycb->dea_wrapping_key_mask,
 			sizeof(kvm->arch.crypto.crycb->dea_wrapping_key_mask));
 		kvm->arch.crypto.dea_kw = 1;
+		VM_EVENT(kvm, 3, "%s", "ENABLE: DEA keywrapping support");
 		break;
 	case KVM_S390_VM_CRYPTO_DISABLE_AES_KW:
 		kvm->arch.crypto.aes_kw = 0;
 		memset(kvm->arch.crypto.crycb->aes_wrapping_key_mask, 0,
 			sizeof(kvm->arch.crypto.crycb->aes_wrapping_key_mask));
+		VM_EVENT(kvm, 3, "%s", "DISABLE: AES keywrapping support");
 		break;
 	case KVM_S390_VM_CRYPTO_DISABLE_DEA_KW:
 		kvm->arch.crypto.dea_kw = 0;
 		memset(kvm->arch.crypto.crycb->dea_wrapping_key_mask, 0,
 			sizeof(kvm->arch.crypto.crycb->dea_wrapping_key_mask));
+		VM_EVENT(kvm, 3, "%s", "DISABLE: DEA keywrapping support");
 		break;
 	default:
 		mutex_unlock(&kvm->lock);
@@ -467,6 +481,7 @@
 
 	if (gtod_high != 0)
 		return -EINVAL;
+	VM_EVENT(kvm, 3, "SET: TOD extension: 0x%x\n", gtod_high);
 
 	return 0;
 }
@@ -492,6 +507,7 @@
 		cur_vcpu->arch.sie_block->epoch = kvm->arch.epoch;
 	kvm_s390_vcpu_unblock_all(kvm);
 	mutex_unlock(&kvm->lock);
+	VM_EVENT(kvm, 3, "SET: TOD base: 0x%llx\n", gtod);
 	return 0;
 }
 
@@ -523,6 +539,7 @@
 	if (copy_to_user((void __user *)attr->addr, &gtod_high,
 					 sizeof(gtod_high)))
 		return -EFAULT;
+	VM_EVENT(kvm, 3, "QUERY: TOD extension: 0x%x\n", gtod_high);
 
 	return 0;
 }
@@ -539,6 +556,7 @@
 	gtod = host_tod + kvm->arch.epoch;
 	if (copy_to_user((void __user *)attr->addr, &gtod, sizeof(gtod)))
 		return -EFAULT;
+	VM_EVENT(kvm, 3, "QUERY: TOD base: 0x%llx\n", gtod);
 
 	return 0;
 }
@@ -2360,6 +2378,7 @@
 	case KVM_CAP_S390_CSS_SUPPORT:
 		if (!vcpu->kvm->arch.css_support) {
 			vcpu->kvm->arch.css_support = 1;
+			VM_EVENT(vcpu->kvm, 3, "%s", "ENABLE: CSS support");
 			trace_kvm_s390_enable_css(vcpu->kvm);
 		}
 		r = 0;