Creating IOCTL linux kernel 5.3

Code for creating IOCTL command in linux kernel 5.3 . The details of creation and usage of kerenl is given in the post here

	/* The code has been tested on kerenl 5.3
	The steps to use the icotl in user space is given in
	http://tuxthink.blogspot.com/2011/01/creating-ioctl-command.html
	*/
	#include <linux/module.h>
	#include <linux/kernel.h>
	#include <linux/fs.h> // required for various structures related to files liked fops.
	#include <linux/semaphore.h>
	#include <linux/cdev.h>
	#include "ioctl_basic.h"
	#include <linux/version.h>
	static int Major;
	#if LINUX_VERSION_CODE > KERNEL_VERSION(2,6,36)
	#define UNLOCKED 1
	#endif
	int open(struct inode *inode, struct file *filp)
	{
	printk(KERN_INFO "Inside open \n");
	return 0;
	}
	int release(struct inode *inode, struct file *filp) {
	printk (KERN_INFO "Inside close \n");
	return 0;
	}
	#ifdef UNLOCKED
	long int ioctl_funcs(struct file *filp,unsigned int cmd, unsigned long arg)
	{
	int ret=0;
	switch(cmd) {
	case IOCTL_HELLO:
	printk(KERN_INFO "Hello ioctl world");
	break;
	}
	return ret;
	}
	struct file_operations fops = {
	open: open,
	unlocked_ioctl: ioctl_funcs,
	release: release
	};
	#else
	int ioctl_funcs(struct inode *inode, struct file *filp,
	unsigned int cmd, unsigned long arg)
	{
	int data=10,ret;
	switch(cmd) {
	case IOCTL_HELLO:
	printk(KERN_INFO "Hello ioctl world");
	break;
	}
	return ret;
	}
	struct file_operations fops = {
	open: open,
	ioctl: ioctl_funcs,
	release: release
	};
	#endif
	struct cdev *kernel_cdev;
	int char_arr_init (void) {
	int ret;
	dev_t dev_no,dev;
	kernel_cdev = cdev_alloc();
	kernel_cdev->ops = &fops;
	kernel_cdev->owner = THIS_MODULE;
	printk (" Inside init module\n");
	ret = alloc_chrdev_region( &dev_no , 0, 1,"char_arr_dev");
	if (ret < 0) {
	printk("Major number allocation is failed\n");
	return ret;
	}
	Major = MAJOR(dev_no);
	dev = MKDEV(Major,0);
	printk (" The major number for your device is %d\n", Major);
	ret = cdev_add( kernel_cdev,dev,1);
	if(ret < 0 )
	{
	printk(KERN_INFO "Unable to allocate cdev");
	return ret;
	}
	return 0;
	}
	void char_arr_cleanup(void) {
	printk(KERN_INFO " Inside cleanup_module\n");
	cdev_del(kernel_cdev);
	unregister_chrdev_region(Major, 1);
	}
	MODULE_LICENSE("GPL");
	module_init(char_arr_init);
	module_exit(char_arr_cleanup);

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