学步园

函数原型：

#define class_create(owner, name)		\
({						\
	static struct lock_class_key __key;	\
	__class_create(owner, name, &__key);	\
})

struct device *device_create(struct class *class, struct device *parent,
			     dev_t devt, void *drvdata, const char *fmt, ...)
{
	va_list vargs;
	struct device *dev;

	va_start(vargs, fmt);
	dev = device_create_vargs(class, parent, devt, drvdata, fmt, vargs);
	va_end(vargs);
	return dev;
}

void device_destroy(struct class *class, dev_t devt)
{
 struct device *dev;
 dev = class_find_device(class, NULL, &devt, __match_devt);
 if (dev) {
  put_device(dev);
  device_unregister(dev);
 }
}

void class_destroy(struct class *cls)
{
	if ((cls == NULL) || (IS_ERR(cls)))
		return;

	class_unregister(cls);
}

实例：

在__init函数中，添加以下代码：

my_class= class_create(THIS_MODULE, "my_class");

if(IS_ERR(my_class)) 
{
       printk("Err: failed increating class.\n");

       return -1; 

 }
 device_create( my_class, NULL, devno,NULL, DEV_NAME);//DEV_NAME=设备名;  

在__exit函数中，添加以下代码（在unregister_chrdev_region前）：

device_destroy(virtual_disk_class, MKDEV(VirtualDisk_major, 0));
class_destroy(virtual_disk_class);