rem: return ERR_VM_INVALID_ASPACE;
add: return B_BAD_TEAM_ID;
context: vm_create_null_area(aspace_id aid, const char *name, void **address, uint32 addressSpec, addr_t size){	vm_area *area;	vm_cache *cache;	vm_cache_ref *cache_ref;	vm_store *store;//	addr_t map_offset;	int err;	vm_address_space *aspace = vm_get_aspace_by_id(aid);	if (aspace == NULL)		return ERR_VM_INVALID_ASPACE;	size = PAGE_ALIGN(size);	// create an null store object	store = vm_store_create_null();	if (store == NULL)		panic("vm_map_physical_memory: vm_store_create_null returned NULL");	cache = vm_cache_create(store);	if (cache == NULL)		panic("vm_map_physical_memory: vm_cache_create returned NULL");	cache_ref = vm_cache_ref_create(cache);	if (cache_ref == NULL)		panic("vm_map_physical_memory: vm_cache_ref_create returned NULL");	// tell the page scanner to skip over this area, no pages will be mapped here	cache->scan_skip = 1;	vm_cache_acquire_ref(cache_ref, true);	err = map_backing_store(aspace, store, address, 0, size, addressSpec, 0, B_KERNEL_READ_AREA, REGION_NO_PRIVATE_MAP, &area, name);	vm_cache_release_ref(cache_ref);	vm_put_aspace(aspace);	if (err < 0)		return err;	return area->id;}