2 * proc_tty.c -- handles /proc/tty
4 * Copyright 1997, Theodore Ts'o
7 #include <asm/uaccess.h>
8 #include <linux/module.h>
9 #include <linux/init.h>
10 #include <linux/errno.h>
11 #include <linux/time.h>
12 #include <linux/proc_fs.h>
13 #include <linux/stat.h>
14 #include <linux/tty.h>
15 #include <linux/seq_file.h>
16 #include <linux/bitops.h>
19 * The /proc/tty directory inodes...
21 static struct proc_dir_entry
*proc_tty_ldisc
, *proc_tty_driver
;
24 * This is the handler for /proc/tty/drivers
26 static void show_tty_range(struct seq_file
*m
, struct tty_driver
*p
,
29 seq_printf(m
, "%-20s ", p
->driver_name
? p
->driver_name
: "unknown");
30 seq_printf(m
, "/dev/%-8s ", p
->name
);
32 seq_printf(m
, "%3d %d-%d ", MAJOR(from
), MINOR(from
),
33 MINOR(from
) + num
- 1);
35 seq_printf(m
, "%3d %7d ", MAJOR(from
), MINOR(from
));
38 case TTY_DRIVER_TYPE_SYSTEM
:
39 seq_printf(m
, "system");
40 if (p
->subtype
== SYSTEM_TYPE_TTY
)
41 seq_printf(m
, ":/dev/tty");
42 else if (p
->subtype
== SYSTEM_TYPE_SYSCONS
)
43 seq_printf(m
, ":console");
44 else if (p
->subtype
== SYSTEM_TYPE_CONSOLE
)
45 seq_printf(m
, ":vtmaster");
47 case TTY_DRIVER_TYPE_CONSOLE
:
48 seq_printf(m
, "console");
50 case TTY_DRIVER_TYPE_SERIAL
:
51 seq_printf(m
, "serial");
53 case TTY_DRIVER_TYPE_PTY
:
54 if (p
->subtype
== PTY_TYPE_MASTER
)
55 seq_printf(m
, "pty:master");
56 else if (p
->subtype
== PTY_TYPE_SLAVE
)
57 seq_printf(m
, "pty:slave");
62 seq_printf(m
, "type:%d.%d", p
->type
, p
->subtype
);
67 static int show_tty_driver(struct seq_file
*m
, void *v
)
69 struct tty_driver
*p
= list_entry(v
, struct tty_driver
, tty_drivers
);
70 dev_t from
= MKDEV(p
->major
, p
->minor_start
);
71 dev_t to
= from
+ p
->num
;
73 if (&p
->tty_drivers
== tty_drivers
.next
) {
74 /* pseudo-drivers first */
75 seq_printf(m
, "%-20s /dev/%-8s ", "/dev/tty", "tty");
76 seq_printf(m
, "%3d %7d ", TTYAUX_MAJOR
, 0);
77 seq_printf(m
, "system:/dev/tty\n");
78 seq_printf(m
, "%-20s /dev/%-8s ", "/dev/console", "console");
79 seq_printf(m
, "%3d %7d ", TTYAUX_MAJOR
, 1);
80 seq_printf(m
, "system:console\n");
81 #ifdef CONFIG_UNIX98_PTYS
82 seq_printf(m
, "%-20s /dev/%-8s ", "/dev/ptmx", "ptmx");
83 seq_printf(m
, "%3d %7d ", TTYAUX_MAJOR
, 2);
84 seq_printf(m
, "system\n");
87 seq_printf(m
, "%-20s /dev/%-8s ", "/dev/vc/0", "vc/0");
88 seq_printf(m
, "%3d %7d ", TTY_MAJOR
, 0);
89 seq_printf(m
, "system:vtmaster\n");
93 while (MAJOR(from
) < MAJOR(to
)) {
94 dev_t next
= MKDEV(MAJOR(from
)+1, 0);
95 show_tty_range(m
, p
, from
, next
- from
);
99 show_tty_range(m
, p
, from
, to
- from
);
104 static void *t_start(struct seq_file
*m
, loff_t
*pos
)
106 mutex_lock(&tty_mutex
);
107 return seq_list_start(&tty_drivers
, *pos
);
110 static void *t_next(struct seq_file
*m
, void *v
, loff_t
*pos
)
112 return seq_list_next(v
, &tty_drivers
, pos
);
115 static void t_stop(struct seq_file
*m
, void *v
)
117 mutex_unlock(&tty_mutex
);
120 static const struct seq_operations tty_drivers_op
= {
124 .show
= show_tty_driver
127 static int tty_drivers_open(struct inode
*inode
, struct file
*file
)
129 return seq_open(file
, &tty_drivers_op
);
132 static const struct file_operations proc_tty_drivers_operations
= {
133 .open
= tty_drivers_open
,
136 .release
= seq_release
,
139 static void * tty_ldiscs_seq_start(struct seq_file
*m
, loff_t
*pos
)
141 return (*pos
< NR_LDISCS
) ? pos
: NULL
;
144 static void * tty_ldiscs_seq_next(struct seq_file
*m
, void *v
, loff_t
*pos
)
147 return (*pos
< NR_LDISCS
) ? pos
: NULL
;
150 static void tty_ldiscs_seq_stop(struct seq_file
*m
, void *v
)
154 static int tty_ldiscs_seq_show(struct seq_file
*m
, void *v
)
156 int i
= *(loff_t
*)v
;
157 struct tty_ldisc
*ld
;
159 ld
= tty_ldisc_get(i
);
162 seq_printf(m
, "%-10s %2d\n", ld
->name
? ld
->name
: "???", i
);
167 static const struct seq_operations tty_ldiscs_seq_ops
= {
168 .start
= tty_ldiscs_seq_start
,
169 .next
= tty_ldiscs_seq_next
,
170 .stop
= tty_ldiscs_seq_stop
,
171 .show
= tty_ldiscs_seq_show
,
174 static int proc_tty_ldiscs_open(struct inode
*inode
, struct file
*file
)
176 return seq_open(file
, &tty_ldiscs_seq_ops
);
179 static const struct file_operations tty_ldiscs_proc_fops
= {
180 .owner
= THIS_MODULE
,
181 .open
= proc_tty_ldiscs_open
,
184 .release
= seq_release
,
188 * This function is called by tty_register_driver() to handle
189 * registering the driver's /proc handler into /proc/tty/driver/<foo>
191 void proc_tty_register_driver(struct tty_driver
*driver
)
193 struct proc_dir_entry
*ent
;
195 if (!driver
->ops
->read_proc
|| !driver
->driver_name
||
199 ent
= create_proc_entry(driver
->driver_name
, 0, proc_tty_driver
);
202 ent
->read_proc
= driver
->ops
->read_proc
;
203 ent
->owner
= driver
->owner
;
206 driver
->proc_entry
= ent
;
210 * This function is called by tty_unregister_driver()
212 void proc_tty_unregister_driver(struct tty_driver
*driver
)
214 struct proc_dir_entry
*ent
;
216 ent
= driver
->proc_entry
;
220 remove_proc_entry(driver
->driver_name
, proc_tty_driver
);
222 driver
->proc_entry
= NULL
;
226 * Called by proc_root_init() to initialize the /proc/tty subtree
228 void __init
proc_tty_init(void)
230 if (!proc_mkdir("tty", NULL
))
232 proc_tty_ldisc
= proc_mkdir("tty/ldisc", NULL
);
234 * /proc/tty/driver/serial reveals the exact character counts for
235 * serial links which is just too easy to abuse for inferring
236 * password lengths and inter-keystroke timings during password
239 proc_tty_driver
= proc_mkdir_mode("tty/driver", S_IRUSR
|S_IXUSR
, NULL
);
240 proc_create("tty/ldiscs", 0, NULL
, &tty_ldiscs_proc_fops
);
241 proc_create("tty/drivers", 0, NULL
, &proc_tty_drivers_operations
);