+--
+[mandatory]
+ ->d_compare() doesn't get parent as a separate argument anymore. If you
+ used it for finding the struct super_block involved, dentry->d_sb will
+ work just as well; if it's something more complicated, use dentry->d_parent.
+ Just be careful not to assume that fetching it more than once will yield
+ the same value - in RCU mode it could change under you.