NTFS: Make ntfs_write_block() not instantiate sparse blocks if they are zero.

Signed-off-by: Anton Altaparmakov <aia21@cantab.net>
diff --git a/fs/ntfs/ChangeLog b/fs/ntfs/ChangeLog
index ed8d001..b176664 100644
--- a/fs/ntfs/ChangeLog
+++ b/fs/ntfs/ChangeLog
@@ -77,6 +77,8 @@
 	  updating the times in the inode in ntfs_setattr().
 	- Fixup handling of sparse, compressed, and encrypted attributes in
 	  fs/ntfs/inode.c::ntfs_read_locked_{,attr_,index_}inode().
+	- Make ntfs_write_block() not instantiate sparse blocks if they contain
+	  only zeroes.
 
 2.1.23 - Implement extension of resident files and make writing safe as well as
 	 many bug fixes, cleanups, and enhancements...