[PATCH] KVM: API versioning

Add compile-time and run-time API versioning.

Signed-off-by: Avi Kivity <avi@qumranet.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
diff --git a/drivers/kvm/kvm_main.c b/drivers/kvm/kvm_main.c
index bc2e6c1..9f24f22 100644
--- a/drivers/kvm/kvm_main.c
+++ b/drivers/kvm/kvm_main.c
@@ -1603,6 +1603,9 @@
 	int r = -EINVAL;
 
 	switch (ioctl) {
+	case KVM_GET_API_VERSION:
+		r = KVM_API_VERSION;
+		break;
 	case KVM_CREATE_VCPU: {
 		r = kvm_dev_ioctl_create_vcpu(kvm, arg);
 		if (r)