vmaprange
extern vaddr_t vmaprange(struct proc *, vaddr_t, vsize_t, int);
up = (char *)vmaprange(p, (vaddr_t)uaddr, len, VM_PROT_READ);
up = (char *)vmaprange(p, (vaddr_t)uaddr, len,
vaddr_t vmaprange(struct proc *, vaddr_t, vsize_t, int);