PG_anon_exclusive
return test_bit(PG_anon_exclusive, &PF_ANY(page, 1)->flags.f);
set_bit(PG_anon_exclusive, &PF_ANY(page, 1)->flags.f);
clear_bit(PG_anon_exclusive, &PF_ANY(page, 1)->flags.f);
__clear_bit(PG_anon_exclusive, &PF_ANY(page, 1)->flags.f);