diff --git a/dll/win32/ubtrfs/ubtrfs.spec b/dll/win32/ubtrfs/ubtrfs.spec
index d36ea230f99..b797157b4c2 100644
--- a/dll/win32/ubtrfs/ubtrfs.spec
+++ b/dll/win32/ubtrfs/ubtrfs.spec
@@ -1,2 +1,6 @@
 @ stdcall ChkdskEx(ptr long long long long ptr) BtrfsChkdskEx
 @ stdcall FormatEx(ptr long ptr long long ptr) BtrfsFormatEx
+
+@ stdcall GetFilesystemInformation(long long ptr)
+@ stdcall SetIncompatFlags(int64)
+@ stdcall SetSizes(long long)