ZONES_MASK 964 include/linux/mm.h return (page->flags >> ZONES_PGSHIFT) & ZONES_MASK; ZONES_MASK 1279 include/linux/mm.h page->flags &= ~(ZONES_MASK << ZONES_PGSHIFT); ZONES_MASK 1280 include/linux/mm.h page->flags |= (zone & ZONES_MASK) << ZONES_PGSHIFT; ZONES_MASK 120 mm/mm_init.c or_mask = (ZONES_MASK << ZONES_PGSHIFT) | ZONES_MASK 123 mm/mm_init.c add_mask = (ZONES_MASK << ZONES_PGSHIFT) +