KVM: s390: Add a generic function for translating guest addresses

This patch adds a function for translating logical guest addresses into
physical guest addresses without touching the memory at the given location.

Signed-off-by: Thomas Huth <thuth@linux.vnet.ibm.com>
Reviewed-by: Cornelia Huck <cornelia.huck@de.ibm.com>
diff --git a/arch/s390/kvm/gaccess.h b/arch/s390/kvm/gaccess.h
index a07ee08..2d37a46 100644
--- a/arch/s390/kvm/gaccess.h
+++ b/arch/s390/kvm/gaccess.h
@@ -155,6 +155,9 @@
 	return kvm_read_guest(vcpu->kvm, gpa, data, len);
 }
 
+int guest_translate_address(struct kvm_vcpu *vcpu, unsigned long gva,
+			    unsigned long *gpa, int write);
+
 int access_guest(struct kvm_vcpu *vcpu, unsigned long ga, void *data,
 		 unsigned long len, int write);