88 /* * Flush operation. This can be used to invalidate: * 1) name cache for one node * 2) name cache for all children * 3) name cache for the entire mount * 4) page cache for a set of ranges in one node * 5) page cache for one entire node * * It can be used to flush: * 1) page cache for a set of ranges in one node * 2) page cache for one entire node */