MAXMINOR
if (dev_num >= MAXMINOR)
rc = cdev_add(vmlogrdr_cdev, dev, MAXMINOR);
for (i=0; i < MAXMINOR; ++i ) {
unregister_chrdev_region(MKDEV(vmlogrdr_major, 0), MAXMINOR);
rc = alloc_chrdev_region(&dev, 0, MAXMINOR, "vmlogrdr");
for (i=0; i < MAXMINOR; ++i ) {