[PATCH] ecryptfs: nested locking annotation

ecryptfs uses a lock_parent() function, which I hope really locks the parents
and is not abused

Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Michael Halcrow <mhalcrow@us.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>