#include <linux/fs.h>#include <linux/init.h>#include <linux/proc_fs.h>#include <linux/seq_file.h> static int devinfo_show(struct seq_file *f, void *v){	int i = *(loff_t *) v; 	if (i < CHRDEV_MAJOR_HASH_SIZE) {		if (i == 0)			seq_puts(f, "Character devices:\n");		chrdev_show(f, i);	}#ifdef CONFIG_BLOCK	else {		i -= CHRDEV_MAJOR_HASH_SIZE;		if (i == 0)			seq_puts(f, "\nBlock devices:\n");		blkdev_show(f, i);	}#endif	return 0;} static void *devinfo_start(struct seq_file *f, loff_t *pos){	if (*pos < (BLKDEV_MAJOR_HASH_SIZE + CHRDEV_MAJOR_HASH_SIZE))		return pos;	return NULL;} static void *devinfo_next(struct seq_file *f, void *v, loff_t *pos){	(*pos)++;	if (*pos >= (BLKDEV_MAJOR_HASH_SIZE + CHRDEV_MAJOR_HASH_SIZE))		return NULL;	return pos;} static void devinfo_stop(struct seq_file *f, void *v){	/* Nothing to do */} static const struct seq_operations devinfo_ops = {	.start = devinfo_start,	.next  = devinfo_next,	.stop  = devinfo_stop,	.show  = devinfo_show}; static int devinfo_open(struct inode *inode, struct file *filp){	return seq_open(filp, &devinfo_ops);} static const struct file_operations proc_devinfo_operations = {	.open		= devinfo_open,	.read		= seq_read,	.llseek		= seq_lseek,	.release	= seq_release,}; static int __init proc_devices_init(void){	proc_create("devices", 0, NULL, &proc_devinfo_operations);	return 0;}module_init(proc_devices_init);