1// SPDX-License-Identifier: GPL-2.0
 2#include <linux/fs.h>
 3#include <linux/init.h>
 4#include <linux/proc_fs.h>
 5#include <linux/seq_file.h>
 6#include <linux/blkdev.h>
 7
 8static int devinfo_show(struct seq_file *f, void *v)
 9{
10	int i = *(loff_t *) v;
11
12	if (i < CHRDEV_MAJOR_MAX) {
13		if (i == 0)
14			seq_puts(f, "Character devices:\n");
15		chrdev_show(f, i);
16	}
17#ifdef CONFIG_BLOCK
18	else {
19		i -= CHRDEV_MAJOR_MAX;
20		if (i == 0)
21			seq_puts(f, "\nBlock devices:\n");
22		blkdev_show(f, i);
23	}
24#endif
25	return 0;
26}
27
28static void *devinfo_start(struct seq_file *f, loff_t *pos)
29{
30	if (*pos < (BLKDEV_MAJOR_MAX + CHRDEV_MAJOR_MAX))
31		return pos;
32	return NULL;
33}
34
35static void *devinfo_next(struct seq_file *f, void *v, loff_t *pos)
36{
37	(*pos)++;
38	if (*pos >= (BLKDEV_MAJOR_MAX + CHRDEV_MAJOR_MAX))
39		return NULL;
40	return pos;
41}
42
43static void devinfo_stop(struct seq_file *f, void *v)
44{
45	/* Nothing to do */
46}
47
48static const struct seq_operations devinfo_ops = {
49	.start = devinfo_start,
50	.next  = devinfo_next,
51	.stop  = devinfo_stop,
52	.show  = devinfo_show
53};
54
55static int __init proc_devices_init(void)
56{
57	proc_create_seq("devices", 0, NULL, &devinfo_ops);
58	return 0;
59}
60fs_initcall(proc_devices_init);

 1// SPDX-License-Identifier: GPL-2.0
 2#include <linux/fs.h>
 3#include <linux/init.h>
 4#include <linux/proc_fs.h>
 5#include <linux/seq_file.h>
 
 6
 7static int devinfo_show(struct seq_file *f, void *v)
 8{
 9	int i = *(loff_t *) v;
10
11	if (i < CHRDEV_MAJOR_MAX) {
12		if (i == 0)
13			seq_puts(f, "Character devices:\n");
14		chrdev_show(f, i);
15	}
16#ifdef CONFIG_BLOCK
17	else {
18		i -= CHRDEV_MAJOR_MAX;
19		if (i == 0)
20			seq_puts(f, "\nBlock devices:\n");
21		blkdev_show(f, i);
22	}
23#endif
24	return 0;
25}
26
27static void *devinfo_start(struct seq_file *f, loff_t *pos)
28{
29	if (*pos < (BLKDEV_MAJOR_MAX + CHRDEV_MAJOR_MAX))
30		return pos;
31	return NULL;
32}
33
34static void *devinfo_next(struct seq_file *f, void *v, loff_t *pos)
35{
36	(*pos)++;
37	if (*pos >= (BLKDEV_MAJOR_MAX + CHRDEV_MAJOR_MAX))
38		return NULL;
39	return pos;
40}
41
42static void devinfo_stop(struct seq_file *f, void *v)
43{
44	/* Nothing to do */
45}
46
47static const struct seq_operations devinfo_ops = {
48	.start = devinfo_start,
49	.next  = devinfo_next,
50	.stop  = devinfo_stop,
51	.show  = devinfo_show
52};
53
54static int __init proc_devices_init(void)
55{
56	proc_create_seq("devices", 0, NULL, &devinfo_ops);
57	return 0;
58}
59fs_initcall(proc_devices_init);