diff --git a/xtldr/includes/xtldr.h b/xtldr/includes/xtldr.h
index 0eb7b75..3e7937e 100644
--- a/xtldr/includes/xtldr.h
+++ b/xtldr/includes/xtldr.h
@@ -29,6 +29,10 @@ EFI_STATUS
 BlAllocateMemoryPool(IN UINT_PTR Size,
                      OUT PVOID *Memory);
 
+XTCDECL
+EFI_STATUS
+BlBuildPageMap(IN PXTBL_PAGE_MAPPING PageMap);
+
 XTCDECL
 VOID
 BlClearConsoleLine(IN ULONGLONG LineNo);