diff --git a/include/ntfs/runlist.h b/include/ntfs/runlist.h
index 0d066598..726a28dc 100644
--- a/include/ntfs/runlist.h
+++ b/include/ntfs/runlist.h
@@ -62,9 +62,14 @@ extern runlist_element *ntfs_runlists_merge(runlist_element *drl,
 extern runlist_element *ntfs_mapping_pairs_decompress(const ntfs_volume *vol,
 		const ATTR_RECORD *attr, runlist_element *old_rl);
 
+extern int ntfs_get_nr_significant_bytes(const s64 n);
+
 extern int ntfs_get_size_for_mapping_pairs(const ntfs_volume *vol,
 		const runlist_element *rl, const VCN start_vcn);
 
+extern int ntfs_write_significant_bytes(u8 *dst, const u8 *dst_max,
+		const s64 n);
+
 extern int ntfs_mapping_pairs_build(const ntfs_volume *vol, u8 *dst,
 		const int dst_len, const runlist_element *rl,
 		const VCN start_vcn, VCN *const stop_vcn);