failed fops attempt

kernel_module/ioctl.c

@@ -0,0 +1,36 @@
+/*
+Give integer and a pointer to the kernel, and get one positive integer out.
+*/
+
+#include <linux/debugfs.h>
+#include <linux/module.h>
+#include <linux/printk.h> /* printk */
+
+MODULE_LICENSE("GPL");
+
+static struct dentry *dir;
+
+static long unlocked_ioctl(struct file *filp, unsigned int cmd, unsigned long arg)
+{
+	pr_info("cmd = %u\n", cmd);
+	return cmd + 1;
+}
+
+static const struct file_operations fops = {
+	.unlocked_ioctl = unlocked_ioctl
+};
+
+static int myinit(void)
+{
+	dir = debugfs_create_dir("lkmc_ioctl", 0);
+	debugfs_create_file("f", 0666, dir, NULL, &fops);
+	return 0;
+}
+
+static void myexit(void)
+{
+	debugfs_remove_recursive(dir);
+}
+
+module_init(myinit)
+module_exit(myexit)