KVM: x86/xen: Add KVM_XEN_VCPU_SET_ATTR/KVM_XEN_VCPU_GET_ATTR

This will be used for per-vCPU setup such as runstate and vcpu_info.

Signed-off-by: David Woodhouse <dwmw@amazon.co.uk>
diff --git a/arch/x86/kvm/xen.c b/arch/x86/kvm/xen.c
index eab4dce..5cbf695 100644
--- a/arch/x86/kvm/xen.c
+++ b/arch/x86/kvm/xen.c
@@ -118,6 +118,36 @@ int kvm_xen_hvm_get_attr(struct kvm *kvm, struct kvm_xen_hvm_attr *data)
 	return r;
 }
 
+int kvm_xen_vcpu_set_attr(struct kvm_vcpu *vcpu, struct kvm_xen_vcpu_attr *data)
+{
+	int r = -ENOENT;
+
+	mutex_lock(&vcpu->kvm->lock);
+
+	switch (data->type) {
+	default:
+		break;
+	}
+
+	mutex_unlock(&vcpu->kvm->lock);
+	return r;
+}
+
+int kvm_xen_vcpu_get_attr(struct kvm_vcpu *vcpu, struct kvm_xen_vcpu_attr *data)
+{
+	int r = -ENOENT;
+
+	mutex_lock(&vcpu->kvm->lock);
+
+	switch (data->type) {
+	default:
+		break;
+	}
+
+	mutex_unlock(&vcpu->kvm->lock);
+	return r;
+}
+
 int kvm_xen_write_hypercall_page(struct kvm_vcpu *vcpu, u64 data)
 {
 	struct kvm *kvm = vcpu->kvm;