vm_mmap_cdev
error = vm_mmap_cdev(td, size, prot, &maxprot, &flags, dev, dsw, &foff,
int vm_mmap_cdev(struct thread *, vm_size_t, vm_prot_t, vm_prot_t *,
error = vm_mmap_cdev(td, size, prot, &maxprot, &flags, cdev,