cdbr_open_mem
cdbr = cdbr_open_mem(base, size, flags, cdbr_unmap, NULL);
__weak_alias(cdbr_open_mem,_cdbr_open_mem)
t->t_cdb = cdbr_open_mem(t->t_blob, size,
struct cdbr *cdbr_open_mem(void *, size_t, int,