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>

arch/s390/kvm/kvm-s390.c

@@ -299,10 +299,12 @@ static int kvm_vm_ioctl_enable_cap(struct kvm *kvm, struct kvm_enable_cap *cap)
 
 	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 @@ static int kvm_vm_ioctl_enable_cap(struct kvm *kvm, struct kvm_enable_cap *cap)
 			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 @@ static int kvm_s390_get_mem_control(struct kvm *kvm, struct kvm_device_attr *att
 	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 @@ static int kvm_s390_set_mem_control(struct kvm *kvm, struct kvm_device_attr *att
 			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 @@ static int kvm_s390_set_mem_control(struct kvm *kvm, struct kvm_device_attr *att
 		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 @@ static int kvm_s390_set_mem_control(struct kvm *kvm, struct kvm_device_attr *att
 			}
 		}
 		mutex_unlock(&kvm->lock);
+		VM_EVENT(kvm, 3, "SET: max guest memory: %lu bytes", new_limit);
 		break;
 	}
 	default:
@@ -427,22 +437,26 @@ static int kvm_s390_vm_set_crypto(struct kvm *kvm, struct kvm_device_attr *attr)
 			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 @@ static int kvm_s390_set_tod_high(struct kvm *kvm, struct kvm_device_attr *attr)
 
 	if (gtod_high != 0)
 		return -EINVAL;
+	VM_EVENT(kvm, 3, "SET: TOD extension: 0x%x\n", gtod_high);
 
 	return 0;
 }
@@ -492,6 +507,7 @@ static int kvm_s390_set_tod_low(struct kvm *kvm, struct kvm_device_attr *attr)
 		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 @@ static int kvm_s390_get_tod_high(struct kvm *kvm, struct kvm_device_attr *attr)
 	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 @@ static int kvm_s390_get_tod_low(struct kvm *kvm, struct kvm_device_attr *attr)
 	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 @@ static int kvm_vcpu_ioctl_enable_cap(struct kvm_vcpu *vcpu,
 	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;