@Override
  void linked(DirectoryEntry entry) {
    File parent = entry.directory(); // handles null check
    this.entryInParent = entry;
    forcePut(new DirectoryEntry(this, Name.PARENT, parent));
  }
Returns the parent of this directory. If this directory has been deleted, this returns the
directory it was in when it was deleted.
jimfs/src/main/java/com/google/common/jimfs/Directory.java