NTFS: Add fs/ntfs/runlist.[hc]::ntfs_get_nr_significant_bytes(),

      ntfs_get_size_for_mapping_pairs(), ntfs_write_significant_bytes(),
      and ntfs_mapping_pairs_build(), adapted from libntfs.
Signed-off-by: Anton Altaparmakov <aia21@cantab.net>

fs/ntfs/ChangeLog

@@ -30,6 +30,9 @@ ToDo/Notes:
 	- Rename init_runlist() to ntfs_init_runlist(), ntfs_vcn_to_lcn() to
 	  ntfs_rl_vcn_to_lcn(), decompress_mapping_pairs() to
 	  ntfs_mapping_pairs_decompress() and adapt all callers.
+	- Add fs/ntfs/runlist.[hc]::ntfs_get_nr_significant_bytes(),
+	  ntfs_get_size_for_mapping_pairs(), ntfs_write_significant_bytes(),
+	  and ntfs_mapping_pairs_build(), adapted from libntfs.
 
 2.1.19 - Many cleanups, improvements, and a minor bug fix.
 

fs/ntfs/runlist.h

@@ -45,4 +45,11 @@ extern runlist_element *ntfs_mapping_pairs_decompress(const ntfs_volume *vol,
 
 extern LCN ntfs_rl_vcn_to_lcn(const runlist_element *rl, const VCN vcn);
 
+extern int ntfs_get_size_for_mapping_pairs(const ntfs_volume *vol,
+		const runlist_element *rl, const VCN start_vcn);
+
+extern int ntfs_mapping_pairs_build(const ntfs_volume *vol, s8 *dst,
+		const int dst_len, const runlist_element *rl,
+		const VCN start_vcn, VCN *const stop_vcn);
+
 #endif /* _LINUX_NTFS_RUNLIST_H */