rem: start += B_PAGE_SIZE;
add: current += B_PAGE_SIZE;
context: unmap_and_free_physical_pages(vm_translation_map *map, addr_t start, addr_t end){	// free all physical pages behind the specified range	while (start < end) {		addr_t physicalAddress;		uint32 flags;		if (map->ops->query(map, start, &physicalAddress, &flags) == B_OK) {			vm_page *page = vm_lookup_page(start / B_PAGE_SIZE);			if (page != NULL)				vm_page_set_state(page, PAGE_STATE_FREE);		}		start += B_PAGE_SIZE;	}	// unmap the memory	map->ops->unmap(map, start, end - 1);}