pg_class_t
pg_class_t pg_class;
static pg_class_t *pg_classes;
pg_class_t *newclass;
pg_class_t *classes_old;
pg_classes = kmem_zalloc(sizeof (pg_class_t), KM_SLEEP);
kmem_zalloc(sizeof (pg_class_t) * (pg_nclasses + 1),
sizeof (pg_class_t) * pg_nclasses);
kmem_free(classes_old, sizeof (pg_class_t) * pg_nclasses);
pg_alloc_default(pg_class_t class)
static pg_t *pg_alloc_default(pg_class_t);