blob: 11db7dc8676b6d493cbf1acfd35039a730f8205b [file] [log] [blame]
Linus Torvalds1da177e2005-04-16 15:20:36 -07001/*
Linus Torvalds1da177e2005-04-16 15:20:36 -07002 * Copyright (C) 1991, 1992 Linus Torvalds
3 *
4 * Added support for a Unix98-style ptmx device.
5 * -- C. Scott Ananian <cananian@alumni.princeton.edu>, 14-Jan-1998
Linus Torvalds1da177e2005-04-16 15:20:36 -07006 *
Linus Torvalds1da177e2005-04-16 15:20:36 -07007 */
8
Alan Coxfe9cd962008-10-13 10:43:38 +01009#include <linux/module.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070010
11#include <linux/errno.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070012#include <linux/interrupt.h>
13#include <linux/tty.h>
14#include <linux/tty_flip.h>
15#include <linux/fcntl.h>
Alexey Dobriyand43c36d2009-10-07 17:09:06 +040016#include <linux/sched.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070017#include <linux/string.h>
18#include <linux/major.h>
19#include <linux/mm.h>
20#include <linux/init.h>
Alan Coxd81ed102008-10-13 10:41:42 +010021#include <linux/device.h>
Alan Coxfe9cd962008-10-13 10:43:38 +010022#include <linux/uaccess.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070023#include <linux/bitops.h>
24#include <linux/devpts_fs.h>
Tejun Heo5a0e3ad2010-03-24 17:04:11 +090025#include <linux/slab.h>
Alan Coxd739e652012-05-03 22:22:09 +010026#include <linux/mutex.h>
Peter Hurley01adc802014-09-10 15:06:32 -040027#include <linux/poll.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070028
Alan Coxfe9cd962008-10-13 10:43:38 +010029
Linus Torvalds1da177e2005-04-16 15:20:36 -070030#ifdef CONFIG_UNIX98_PTYS
Roel Kluinda2bdf92009-01-07 18:09:15 -080031static struct tty_driver *ptm_driver;
Linus Torvalds1da177e2005-04-16 15:20:36 -070032static struct tty_driver *pts_driver;
Alan Coxd739e652012-05-03 22:22:09 +010033static DEFINE_MUTEX(devpts_mutex);
Linus Torvalds1da177e2005-04-16 15:20:36 -070034#endif
35
Alan Coxfe9cd962008-10-13 10:43:38 +010036static void pty_close(struct tty_struct *tty, struct file *filp)
Linus Torvalds1da177e2005-04-16 15:20:36 -070037{
Alan Coxfe9cd962008-10-13 10:43:38 +010038 BUG_ON(!tty);
39 if (tty->driver->subtype == PTY_TYPE_MASTER)
40 WARN_ON(tty->count > 1);
41 else {
Peter Hurley699390352013-01-30 12:43:50 -050042 if (test_bit(TTY_IO_ERROR, &tty->flags))
43 return;
Linus Torvalds1da177e2005-04-16 15:20:36 -070044 if (tty->count > 2)
45 return;
46 }
Peter Hurley699390352013-01-30 12:43:50 -050047 set_bit(TTY_IO_ERROR, &tty->flags);
Linus Torvalds1da177e2005-04-16 15:20:36 -070048 wake_up_interruptible(&tty->read_wait);
49 wake_up_interruptible(&tty->write_wait);
Peter Hurley4ed60fc2014-10-16 15:33:28 -040050 spin_lock_irq(&tty->ctrl_lock);
Linus Torvalds1da177e2005-04-16 15:20:36 -070051 tty->packet = 0;
Peter Hurley4ed60fc2014-10-16 15:33:28 -040052 spin_unlock_irq(&tty->ctrl_lock);
Alan Cox89c8d912012-08-08 16:30:13 +010053 /* Review - krefs on tty_link ?? */
Linus Torvalds1da177e2005-04-16 15:20:36 -070054 if (!tty->link)
55 return;
Linus Torvalds1da177e2005-04-16 15:20:36 -070056 set_bit(TTY_OTHER_CLOSED, &tty->link->flags);
57 wake_up_interruptible(&tty->link->read_wait);
58 wake_up_interruptible(&tty->link->write_wait);
59 if (tty->driver->subtype == PTY_TYPE_MASTER) {
60 set_bit(TTY_OTHER_CLOSED, &tty->flags);
Greg Kroah-Hartmance1000d2012-02-24 13:56:36 -080061#ifdef CONFIG_UNIX98_PTYS
Alan Coxd739e652012-05-03 22:22:09 +010062 if (tty->driver == ptm_driver) {
Cong Dingb9f80332013-01-12 05:01:22 +010063 mutex_lock(&devpts_mutex);
Peter Hurley7acf6cd2013-01-30 12:43:49 -050064 if (tty->link->driver_data)
65 devpts_pty_kill(tty->link->driver_data);
Cong Dingb9f80332013-01-12 05:01:22 +010066 mutex_unlock(&devpts_mutex);
Alan Coxd739e652012-05-03 22:22:09 +010067 }
Greg Kroah-Hartmance1000d2012-02-24 13:56:36 -080068#endif
Alan Cox89c8d912012-08-08 16:30:13 +010069 tty_unlock(tty);
Arnd Bergmann11dbf202010-06-18 14:58:07 +020070 tty_vhangup(tty->link);
Alan Cox89c8d912012-08-08 16:30:13 +010071 tty_lock(tty);
Linus Torvalds1da177e2005-04-16 15:20:36 -070072 }
73}
74
75/*
76 * The unthrottle routine is called by the line discipline to signal
77 * that it can receive more characters. For PTY's, the TTY_THROTTLED
78 * flag is always set, to force the line discipline to always call the
Alan Coxfe9cd962008-10-13 10:43:38 +010079 * unthrottle routine when there are fewer than TTY_THRESHOLD_UNTHROTTLE
Linus Torvalds1da177e2005-04-16 15:20:36 -070080 * characters in the queue. This is necessary since each time this
81 * happens, we need to wake up any sleeping processes that could be
82 * (1) trying to send data to the pty, or (2) waiting in wait_until_sent()
83 * for the pty buffer to be drained.
84 */
Alan Coxfe9cd962008-10-13 10:43:38 +010085static void pty_unthrottle(struct tty_struct *tty)
Linus Torvalds1da177e2005-04-16 15:20:36 -070086{
Alan Coxd945cb92009-07-07 16:39:41 +010087 tty_wakeup(tty->link);
Linus Torvalds1da177e2005-04-16 15:20:36 -070088 set_bit(TTY_THROTTLED, &tty->flags);
89}
90
Alan Coxd945cb92009-07-07 16:39:41 +010091/**
92 * pty_space - report space left for writing
93 * @to: tty we are writing into
Linus Torvalds1da177e2005-04-16 15:20:36 -070094 *
Peter Hurley7bfe0b72013-06-15 09:36:08 -040095 * Limit the buffer space used by ptys to 8k.
Linus Torvalds1da177e2005-04-16 15:20:36 -070096 */
Alan Coxd945cb92009-07-07 16:39:41 +010097
98static int pty_space(struct tty_struct *to)
99{
Peter Hurley7bfe0b72013-06-15 09:36:08 -0400100 int n = tty_buffer_space_avail(to->port);
101 return min(n, 8192);
Alan Coxd945cb92009-07-07 16:39:41 +0100102}
103
104/**
105 * pty_write - write to a pty
106 * @tty: the tty we write from
107 * @buf: kernel buffer of data
108 * @count: bytes to write
109 *
110 * Our "hardware" write method. Data is coming from the ldisc which
111 * may be in a non sleeping state. We simply throw this at the other
112 * end of the link as if we were an IRQ handler receiving stuff for
113 * the other side of the pty/tty pair.
114 */
115
Linus Torvaldsac89a912009-09-05 13:27:10 -0700116static int pty_write(struct tty_struct *tty, const unsigned char *buf, int c)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700117{
118 struct tty_struct *to = tty->link;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700119
Alan Coxd945cb92009-07-07 16:39:41 +0100120 if (tty->stopped)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700121 return 0;
122
Alan Coxd945cb92009-07-07 16:39:41 +0100123 if (c > 0) {
124 /* Stuff the data into the input queue of the other end */
Jiri Slaby05c7cd32013-01-03 15:53:04 +0100125 c = tty_insert_flip_string(to->port, buf, c);
Alan Coxd945cb92009-07-07 16:39:41 +0100126 /* And shovel */
Peter Hurley5ede5252013-07-24 08:29:57 -0400127 if (c)
Jiri Slaby2e124b42013-01-03 15:53:06 +0100128 tty_flip_buffer_push(to->port);
Alan Cox762faae2009-06-16 17:01:13 +0100129 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700130 return c;
131}
132
Alan Coxd945cb92009-07-07 16:39:41 +0100133/**
134 * pty_write_room - write space
135 * @tty: tty we are writing from
136 *
137 * Report how many bytes the ldisc can send into the queue for
138 * the other device.
139 */
140
Linus Torvalds1da177e2005-04-16 15:20:36 -0700141static int pty_write_room(struct tty_struct *tty)
142{
Linus Torvalds85dfd81d2009-08-10 13:21:19 -0700143 if (tty->stopped)
144 return 0;
Alan Coxd945cb92009-07-07 16:39:41 +0100145 return pty_space(tty->link);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700146}
147
Alan Coxd945cb92009-07-07 16:39:41 +0100148/**
149 * pty_chars_in_buffer - characters currently in our tx queue
150 * @tty: our tty
Linus Torvalds1da177e2005-04-16 15:20:36 -0700151 *
Alan Coxd945cb92009-07-07 16:39:41 +0100152 * Report how much we have in the transmit queue. As everything is
153 * instantly at the other end this is easy to implement.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700154 */
Alan Coxd945cb92009-07-07 16:39:41 +0100155
Linus Torvalds1da177e2005-04-16 15:20:36 -0700156static int pty_chars_in_buffer(struct tty_struct *tty)
157{
Alan Coxd945cb92009-07-07 16:39:41 +0100158 return 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700159}
160
161/* Set the lock flag on a pty */
Alan Coxfe9cd962008-10-13 10:43:38 +0100162static int pty_set_lock(struct tty_struct *tty, int __user *arg)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700163{
164 int val;
Alan Coxfe9cd962008-10-13 10:43:38 +0100165 if (get_user(val, arg))
Linus Torvalds1da177e2005-04-16 15:20:36 -0700166 return -EFAULT;
167 if (val)
168 set_bit(TTY_PTY_LOCK, &tty->flags);
169 else
170 clear_bit(TTY_PTY_LOCK, &tty->flags);
171 return 0;
172}
173
Cyrill Gorcunov84fd7bd2012-10-24 23:43:22 +0400174static int pty_get_lock(struct tty_struct *tty, int __user *arg)
175{
176 int locked = test_bit(TTY_PTY_LOCK, &tty->flags);
177 return put_user(locked, arg);
178}
179
Cyrill Gorcunov06026d92012-10-24 23:43:20 +0400180/* Set the packet mode on a pty */
181static int pty_set_pktmode(struct tty_struct *tty, int __user *arg)
182{
Cyrill Gorcunov06026d92012-10-24 23:43:20 +0400183 int pktmode;
184
185 if (get_user(pktmode, arg))
186 return -EFAULT;
187
Peter Hurley6054c16e2014-10-16 15:33:25 -0400188 spin_lock_irq(&tty->ctrl_lock);
Cyrill Gorcunov06026d92012-10-24 23:43:20 +0400189 if (pktmode) {
190 if (!tty->packet) {
Cyrill Gorcunov06026d92012-10-24 23:43:20 +0400191 tty->link->ctrl_status = 0;
Peter Hurley2622d732014-10-16 15:33:27 -0400192 smp_mb();
193 tty->packet = 1;
Cyrill Gorcunov06026d92012-10-24 23:43:20 +0400194 }
195 } else
196 tty->packet = 0;
Peter Hurley6054c16e2014-10-16 15:33:25 -0400197 spin_unlock_irq(&tty->ctrl_lock);
Cyrill Gorcunov06026d92012-10-24 23:43:20 +0400198
199 return 0;
200}
201
Cyrill Gorcunov84fd7bd2012-10-24 23:43:22 +0400202/* Get the packet mode of a pty */
203static int pty_get_pktmode(struct tty_struct *tty, int __user *arg)
204{
205 int pktmode = tty->packet;
206 return put_user(pktmode, arg);
207}
208
hyc@symas.com26df6d12010-06-22 10:14:49 -0700209/* Send a signal to the slave */
210static int pty_signal(struct tty_struct *tty, int sig)
211{
hyc@symas.com26df6d12010-06-22 10:14:49 -0700212 struct pid *pgrp;
213
214 if (tty->link) {
Peter Hurley5b239542014-10-16 14:59:45 -0400215 pgrp = tty_get_pgrp(tty->link);
216 if (pgrp)
217 kill_pgrp(pgrp, sig, 1);
hyc@symas.com26df6d12010-06-22 10:14:49 -0700218 put_pid(pgrp);
219 }
220 return 0;
221}
222
Linus Torvalds1da177e2005-04-16 15:20:36 -0700223static void pty_flush_buffer(struct tty_struct *tty)
224{
225 struct tty_struct *to = tty->link;
Alan Coxfe9cd962008-10-13 10:43:38 +0100226
Linus Torvalds1da177e2005-04-16 15:20:36 -0700227 if (!to)
228 return;
Alan Coxd945cb92009-07-07 16:39:41 +0100229 /* tty_buffer_flush(to); FIXME */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700230 if (to->packet) {
Peter Hurley6054c16e2014-10-16 15:33:25 -0400231 spin_lock_irq(&tty->ctrl_lock);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700232 tty->ctrl_status |= TIOCPKT_FLUSHWRITE;
233 wake_up_interruptible(&to->read_wait);
Peter Hurley6054c16e2014-10-16 15:33:25 -0400234 spin_unlock_irq(&tty->ctrl_lock);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700235 }
236}
237
Alan Coxfe9cd962008-10-13 10:43:38 +0100238static int pty_open(struct tty_struct *tty, struct file *filp)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700239{
Linus Torvalds1da177e2005-04-16 15:20:36 -0700240 if (!tty || !tty->link)
Peter Hurley7c61c3d2013-06-13 15:56:37 -0400241 return -ENODEV;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700242
Linus Torvalds1da177e2005-04-16 15:20:36 -0700243 if (test_bit(TTY_OTHER_CLOSED, &tty->flags))
244 goto out;
245 if (test_bit(TTY_PTY_LOCK, &tty->link->flags))
246 goto out;
Peter Hurley80cace72013-01-30 12:43:52 -0500247 if (tty->driver->subtype == PTY_TYPE_SLAVE && tty->link->count != 1)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700248 goto out;
249
Peter Hurley699390352013-01-30 12:43:50 -0500250 clear_bit(TTY_IO_ERROR, &tty->flags);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700251 clear_bit(TTY_OTHER_CLOSED, &tty->link->flags);
252 set_bit(TTY_THROTTLED, &tty->flags);
Peter Hurley7c61c3d2013-06-13 15:56:37 -0400253 return 0;
254
Linus Torvalds1da177e2005-04-16 15:20:36 -0700255out:
Peter Hurley7c61c3d2013-06-13 15:56:37 -0400256 set_bit(TTY_IO_ERROR, &tty->flags);
257 return -EIO;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700258}
259
Alan Coxfe9cd962008-10-13 10:43:38 +0100260static void pty_set_termios(struct tty_struct *tty,
261 struct ktermios *old_termios)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700262{
Peter Hurleydbfcd852014-10-16 15:33:23 -0400263 /* See if packet mode change of state. */
264 if (tty->link && tty->link->packet) {
265 int extproc = (old_termios->c_lflag & EXTPROC) |
266 (tty->termios.c_lflag & EXTPROC);
267 int old_flow = ((old_termios->c_iflag & IXON) &&
268 (old_termios->c_cc[VSTOP] == '\023') &&
269 (old_termios->c_cc[VSTART] == '\021'));
270 int new_flow = (I_IXON(tty) &&
271 STOP_CHAR(tty) == '\023' &&
272 START_CHAR(tty) == '\021');
273 if ((old_flow != new_flow) || extproc) {
Peter Hurley4d8c1df2014-10-16 15:33:24 -0400274 spin_lock_irq(&tty->ctrl_lock);
Peter Hurleydbfcd852014-10-16 15:33:23 -0400275 if (old_flow != new_flow) {
276 tty->ctrl_status &= ~(TIOCPKT_DOSTOP | TIOCPKT_NOSTOP);
277 if (new_flow)
278 tty->ctrl_status |= TIOCPKT_DOSTOP;
279 else
280 tty->ctrl_status |= TIOCPKT_NOSTOP;
281 }
282 if (extproc)
283 tty->ctrl_status |= TIOCPKT_IOCTL;
Peter Hurley4d8c1df2014-10-16 15:33:24 -0400284 spin_unlock_irq(&tty->ctrl_lock);
Peter Hurleydbfcd852014-10-16 15:33:23 -0400285 wake_up_interruptible(&tty->link->read_wait);
286 }
287 }
288
Alan Coxadc8d742012-07-14 15:31:47 +0100289 tty->termios.c_cflag &= ~(CSIZE | PARENB);
290 tty->termios.c_cflag |= (CS8 | CREAD);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700291}
292
Alan Coxfc6f6232009-01-02 13:43:17 +0000293/**
294 * pty_do_resize - resize event
295 * @tty: tty being resized
Alan Coxc774bda2009-01-11 19:46:49 +0000296 * @ws: window size being set.
Alan Coxfc6f6232009-01-02 13:43:17 +0000297 *
Daniel Mack3ad2f3fb2010-02-03 08:01:28 +0800298 * Update the termios variables and send the necessary signals to
Alan Coxfc6f6232009-01-02 13:43:17 +0000299 * peform a terminal resize correctly
300 */
301
Josh Triplett159a8e92012-11-18 21:27:40 -0800302static int pty_resize(struct tty_struct *tty, struct winsize *ws)
Alan Coxfc6f6232009-01-02 13:43:17 +0000303{
304 struct pid *pgrp, *rpgrp;
Alan Coxfc6f6232009-01-02 13:43:17 +0000305 struct tty_struct *pty = tty->link;
306
307 /* For a PTY we need to lock the tty side */
Peter Hurleydee4a0b2013-07-24 16:43:51 -0400308 mutex_lock(&tty->winsize_mutex);
Alan Coxfc6f6232009-01-02 13:43:17 +0000309 if (!memcmp(ws, &tty->winsize, sizeof(*ws)))
310 goto done;
311
Peter Hurley5b239542014-10-16 14:59:45 -0400312 /* Signal the foreground process group of both ptys */
313 pgrp = tty_get_pgrp(tty);
314 rpgrp = tty_get_pgrp(pty);
Alan Coxfc6f6232009-01-02 13:43:17 +0000315
316 if (pgrp)
317 kill_pgrp(pgrp, SIGWINCH, 1);
318 if (rpgrp != pgrp && rpgrp)
319 kill_pgrp(rpgrp, SIGWINCH, 1);
320
321 put_pid(pgrp);
322 put_pid(rpgrp);
323
324 tty->winsize = *ws;
325 pty->winsize = *ws; /* Never used so will go away soon */
326done:
Peter Hurleydee4a0b2013-07-24 16:43:51 -0400327 mutex_unlock(&tty->winsize_mutex);
Alan Coxfc6f6232009-01-02 13:43:17 +0000328 return 0;
329}
330
Alan Coxd1552552012-07-27 18:02:54 +0100331/**
Peter Hurley01adc802014-09-10 15:06:32 -0400332 * pty_start - start() handler
333 * pty_stop - stop() handler
334 * @tty: tty being flow-controlled
335 *
336 * Propagates the TIOCPKT status to the master pty.
337 *
338 * NB: only the master pty can be in packet mode so only the slave
339 * needs start()/stop() handlers
340 */
341static void pty_start(struct tty_struct *tty)
342{
343 unsigned long flags;
344
Peter Hurley01adc802014-09-10 15:06:32 -0400345 if (tty->link && tty->link->packet) {
Peter Hurley54e8e5f2014-10-16 15:33:26 -0400346 spin_lock_irqsave(&tty->ctrl_lock, flags);
Peter Hurley01adc802014-09-10 15:06:32 -0400347 tty->ctrl_status &= ~TIOCPKT_STOP;
348 tty->ctrl_status |= TIOCPKT_START;
Peter Hurley54e8e5f2014-10-16 15:33:26 -0400349 spin_unlock_irqrestore(&tty->ctrl_lock, flags);
Peter Hurley01adc802014-09-10 15:06:32 -0400350 wake_up_interruptible_poll(&tty->link->read_wait, POLLIN);
351 }
Peter Hurley01adc802014-09-10 15:06:32 -0400352}
353
354static void pty_stop(struct tty_struct *tty)
355{
356 unsigned long flags;
357
Peter Hurley01adc802014-09-10 15:06:32 -0400358 if (tty->link && tty->link->packet) {
Peter Hurley54e8e5f2014-10-16 15:33:26 -0400359 spin_lock_irqsave(&tty->ctrl_lock, flags);
Peter Hurley01adc802014-09-10 15:06:32 -0400360 tty->ctrl_status &= ~TIOCPKT_START;
361 tty->ctrl_status |= TIOCPKT_STOP;
Peter Hurley54e8e5f2014-10-16 15:33:26 -0400362 spin_unlock_irqrestore(&tty->ctrl_lock, flags);
Peter Hurley01adc802014-09-10 15:06:32 -0400363 wake_up_interruptible_poll(&tty->link->read_wait, POLLIN);
364 }
Peter Hurley01adc802014-09-10 15:06:32 -0400365}
366
367/**
Alan Coxd1552552012-07-27 18:02:54 +0100368 * pty_common_install - set up the pty pair
369 * @driver: the pty driver
370 * @tty: the tty being instantiated
Rasmus Villemoes2c964a22014-07-10 21:01:22 +0200371 * @legacy: true if this is BSD style
Alan Coxd1552552012-07-27 18:02:54 +0100372 *
373 * Perform the initial set up for the tty/pty pair. Called from the
374 * tty layer when the port is first opened.
375 *
376 * Locking: the caller must hold the tty_mutex
377 */
Jiri Slaby5d249bc2012-06-04 13:35:29 +0200378static int pty_common_install(struct tty_driver *driver, struct tty_struct *tty,
379 bool legacy)
Alan Coxbf970ee2008-10-13 10:42:39 +0100380{
381 struct tty_struct *o_tty;
Jiri Slabyd03702a2012-06-04 13:35:30 +0200382 struct tty_port *ports[2];
Alan Coxbf970ee2008-10-13 10:42:39 +0100383 int idx = tty->index;
Jiri Slaby5d249bc2012-06-04 13:35:29 +0200384 int retval = -ENOMEM;
Alan Coxbf970ee2008-10-13 10:42:39 +0100385
Peter Hurley55199ea2014-11-05 12:12:49 -0500386 /* Opening the slave first has always returned -EIO */
387 if (driver->subtype != PTY_TYPE_MASTER)
388 return -EIO;
389
Jiri Slabyd03702a2012-06-04 13:35:30 +0200390 ports[0] = kmalloc(sizeof **ports, GFP_KERNEL);
391 ports[1] = kmalloc(sizeof **ports, GFP_KERNEL);
Jiri Slaby6f9ea7a2012-08-07 21:47:26 +0200392 if (!ports[0] || !ports[1])
Rasmus Villemoes2c964a22014-07-10 21:01:22 +0200393 goto err;
Alan Coxbf970ee2008-10-13 10:42:39 +0100394 if (!try_module_get(driver->other->owner)) {
395 /* This cannot in fact currently happen */
Rasmus Villemoes2c964a22014-07-10 21:01:22 +0200396 goto err;
Alan Coxbf970ee2008-10-13 10:42:39 +0100397 }
Rasmus Villemoes2c964a22014-07-10 21:01:22 +0200398 o_tty = alloc_tty_struct(driver->other, idx);
399 if (!o_tty)
400 goto err_put_module;
Alan Coxbf970ee2008-10-13 10:42:39 +0100401
Peter Hurley2febdb62014-11-05 12:13:02 -0500402 tty_set_lock_subclass(o_tty);
403
Jiri Slaby5d249bc2012-06-04 13:35:29 +0200404 if (legacy) {
405 /* We always use new tty termios data so we can do this
406 the easy way .. */
407 retval = tty_init_termios(tty);
408 if (retval)
409 goto err_deinit_tty;
Alan Coxbf970ee2008-10-13 10:42:39 +0100410
Jiri Slaby5d249bc2012-06-04 13:35:29 +0200411 retval = tty_init_termios(o_tty);
412 if (retval)
413 goto err_free_termios;
414
415 driver->other->ttys[idx] = o_tty;
416 driver->ttys[idx] = tty;
417 } else {
Alan Coxadc8d742012-07-14 15:31:47 +0100418 memset(&tty->termios_locked, 0, sizeof(tty->termios_locked));
419 tty->termios = driver->init_termios;
420 memset(&o_tty->termios_locked, 0, sizeof(tty->termios_locked));
421 o_tty->termios = driver->other->init_termios;
Jiri Slaby5d249bc2012-06-04 13:35:29 +0200422 }
Alan Coxfe9cd962008-10-13 10:43:38 +0100423
Alan Coxbf970ee2008-10-13 10:42:39 +0100424 /*
425 * Everything allocated ... set up the o_tty structure.
426 */
Alan Coxbf970ee2008-10-13 10:42:39 +0100427 tty_driver_kref_get(driver->other);
Alan Coxbf970ee2008-10-13 10:42:39 +0100428 /* Establish the links in both directions */
429 tty->link = o_tty;
430 o_tty->link = tty;
Jiri Slabyd03702a2012-06-04 13:35:30 +0200431 tty_port_init(ports[0]);
432 tty_port_init(ports[1]);
433 o_tty->port = ports[0];
434 tty->port = ports[1];
Jiri Slaby967fab62012-10-18 22:26:46 +0200435 o_tty->port->itty = o_tty;
Alan Coxbf970ee2008-10-13 10:42:39 +0100436
437 tty_driver_kref_get(driver);
438 tty->count++;
Peter Hurley55199ea2014-11-05 12:12:49 -0500439 o_tty->count++;
Alan Coxbf970ee2008-10-13 10:42:39 +0100440 return 0;
Jiri Slaby8a1b8d72011-03-23 10:48:33 +0100441err_free_termios:
Jiri Slaby5d249bc2012-06-04 13:35:29 +0200442 if (legacy)
443 tty_free_termios(tty);
Jiri Slabya9dccdd2011-03-23 10:48:36 +0100444err_deinit_tty:
445 deinitialize_tty_struct(o_tty);
Rasmus Villemoes2c964a22014-07-10 21:01:22 +0200446 free_tty_struct(o_tty);
447err_put_module:
Rasmus Villemoes07584d42014-07-13 01:44:00 +0200448 module_put(driver->other->owner);
Rasmus Villemoes2c964a22014-07-10 21:01:22 +0200449err:
Jiri Slabyd03702a2012-06-04 13:35:30 +0200450 kfree(ports[0]);
451 kfree(ports[1]);
Jiri Slaby8a1b8d72011-03-23 10:48:33 +0100452 return retval;
Alan Coxbf970ee2008-10-13 10:42:39 +0100453}
454
Jiri Slabyd03702a2012-06-04 13:35:30 +0200455static void pty_cleanup(struct tty_struct *tty)
456{
Jiri Slaby81c79832012-11-15 09:49:49 +0100457 tty_port_put(tty->port);
Jiri Slabyd03702a2012-06-04 13:35:30 +0200458}
459
Jiri Slaby5d249bc2012-06-04 13:35:29 +0200460/* Traditional BSD devices */
461#ifdef CONFIG_LEGACY_PTYS
462
463static int pty_install(struct tty_driver *driver, struct tty_struct *tty)
464{
465 return pty_common_install(driver, tty, true);
466}
467
Alan Coxd1552552012-07-27 18:02:54 +0100468static void pty_remove(struct tty_driver *driver, struct tty_struct *tty)
469{
470 struct tty_struct *pair = tty->link;
471 driver->ttys[tty->index] = NULL;
472 if (pair)
473 pair->driver->ttys[pair->index] = NULL;
474}
475
Alan Cox6caa76b2011-02-14 16:27:22 +0000476static int pty_bsd_ioctl(struct tty_struct *tty,
Linus Torvalds1da177e2005-04-16 15:20:36 -0700477 unsigned int cmd, unsigned long arg)
478{
479 switch (cmd) {
480 case TIOCSPTLCK: /* Set PT Lock (disallow slave open) */
481 return pty_set_lock(tty, (int __user *) arg);
Cyrill Gorcunov84fd7bd2012-10-24 23:43:22 +0400482 case TIOCGPTLCK: /* Get PT Lock status */
483 return pty_get_lock(tty, (int __user *)arg);
Cyrill Gorcunov06026d92012-10-24 23:43:20 +0400484 case TIOCPKT: /* Set PT packet mode */
485 return pty_set_pktmode(tty, (int __user *)arg);
Cyrill Gorcunov84fd7bd2012-10-24 23:43:22 +0400486 case TIOCGPKT: /* Get PT packet mode */
487 return pty_get_pktmode(tty, (int __user *)arg);
hyc@symas.com26df6d12010-06-22 10:14:49 -0700488 case TIOCSIG: /* Send signal to other side of pty */
489 return pty_signal(tty, (int) arg);
Jiri Slabyded2f2952013-01-11 12:06:27 +0100490 case TIOCGPTN: /* TTY returns ENOTTY, but glibc expects EINVAL here */
491 return -EINVAL;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700492 }
493 return -ENOIOCTLCMD;
494}
495
Kay Sieversdc8c8582007-08-15 12:25:38 +0200496static int legacy_count = CONFIG_LEGACY_PTY_COUNT;
497module_param(legacy_count, int, 0);
498
Linus Torvalds342a5972009-09-30 07:49:40 -0700499/*
500 * The master side of a pty can do TIOCSPTLCK and thus
501 * has pty_bsd_ioctl.
502 */
503static const struct tty_operations master_pty_ops_bsd = {
504 .install = pty_install,
Alan Cox3e8e88c2008-04-30 00:54:10 -0700505 .open = pty_open,
506 .close = pty_close,
507 .write = pty_write,
508 .write_room = pty_write_room,
509 .flush_buffer = pty_flush_buffer,
510 .chars_in_buffer = pty_chars_in_buffer,
511 .unthrottle = pty_unthrottle,
Alan Cox3e8e88c2008-04-30 00:54:10 -0700512 .ioctl = pty_bsd_ioctl,
Jiri Slabyd03702a2012-06-04 13:35:30 +0200513 .cleanup = pty_cleanup,
Alan Coxd1552552012-07-27 18:02:54 +0100514 .resize = pty_resize,
515 .remove = pty_remove
Alan Cox3e8e88c2008-04-30 00:54:10 -0700516};
517
Linus Torvalds342a5972009-09-30 07:49:40 -0700518static const struct tty_operations slave_pty_ops_bsd = {
519 .install = pty_install,
520 .open = pty_open,
521 .close = pty_close,
522 .write = pty_write,
523 .write_room = pty_write_room,
524 .flush_buffer = pty_flush_buffer,
525 .chars_in_buffer = pty_chars_in_buffer,
526 .unthrottle = pty_unthrottle,
527 .set_termios = pty_set_termios,
Jiri Slabyd03702a2012-06-04 13:35:30 +0200528 .cleanup = pty_cleanup,
Alan Coxd1552552012-07-27 18:02:54 +0100529 .resize = pty_resize,
Peter Hurley01adc802014-09-10 15:06:32 -0400530 .start = pty_start,
531 .stop = pty_stop,
Alan Coxd1552552012-07-27 18:02:54 +0100532 .remove = pty_remove
Linus Torvalds342a5972009-09-30 07:49:40 -0700533};
534
Linus Torvalds1da177e2005-04-16 15:20:36 -0700535static void __init legacy_pty_init(void)
536{
Linus Torvalds342a5972009-09-30 07:49:40 -0700537 struct tty_driver *pty_driver, *pty_slave_driver;
538
Kay Sieversdc8c8582007-08-15 12:25:38 +0200539 if (legacy_count <= 0)
540 return;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700541
Jiri Slaby21aca2f2012-08-08 22:26:41 +0200542 pty_driver = tty_alloc_driver(legacy_count,
543 TTY_DRIVER_RESET_TERMIOS |
544 TTY_DRIVER_REAL_RAW |
545 TTY_DRIVER_DYNAMIC_ALLOC);
Dan Carpenterc3a63442012-08-16 16:16:56 +0300546 if (IS_ERR(pty_driver))
Linus Torvalds1da177e2005-04-16 15:20:36 -0700547 panic("Couldn't allocate pty driver");
548
Jiri Slaby21aca2f2012-08-08 22:26:41 +0200549 pty_slave_driver = tty_alloc_driver(legacy_count,
550 TTY_DRIVER_RESET_TERMIOS |
551 TTY_DRIVER_REAL_RAW |
552 TTY_DRIVER_DYNAMIC_ALLOC);
Dan Carpenterc3a63442012-08-16 16:16:56 +0300553 if (IS_ERR(pty_slave_driver))
Linus Torvalds1da177e2005-04-16 15:20:36 -0700554 panic("Couldn't allocate pty slave driver");
555
Linus Torvalds1da177e2005-04-16 15:20:36 -0700556 pty_driver->driver_name = "pty_master";
557 pty_driver->name = "pty";
Linus Torvalds1da177e2005-04-16 15:20:36 -0700558 pty_driver->major = PTY_MASTER_MAJOR;
559 pty_driver->minor_start = 0;
560 pty_driver->type = TTY_DRIVER_TYPE_PTY;
561 pty_driver->subtype = PTY_TYPE_MASTER;
562 pty_driver->init_termios = tty_std_termios;
563 pty_driver->init_termios.c_iflag = 0;
564 pty_driver->init_termios.c_oflag = 0;
565 pty_driver->init_termios.c_cflag = B38400 | CS8 | CREAD;
566 pty_driver->init_termios.c_lflag = 0;
Alan Cox606d0992006-12-08 02:38:45 -0800567 pty_driver->init_termios.c_ispeed = 38400;
568 pty_driver->init_termios.c_ospeed = 38400;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700569 pty_driver->other = pty_slave_driver;
Linus Torvalds342a5972009-09-30 07:49:40 -0700570 tty_set_operations(pty_driver, &master_pty_ops_bsd);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700571
Linus Torvalds1da177e2005-04-16 15:20:36 -0700572 pty_slave_driver->driver_name = "pty_slave";
573 pty_slave_driver->name = "ttyp";
Linus Torvalds1da177e2005-04-16 15:20:36 -0700574 pty_slave_driver->major = PTY_SLAVE_MAJOR;
575 pty_slave_driver->minor_start = 0;
576 pty_slave_driver->type = TTY_DRIVER_TYPE_PTY;
577 pty_slave_driver->subtype = PTY_TYPE_SLAVE;
578 pty_slave_driver->init_termios = tty_std_termios;
579 pty_slave_driver->init_termios.c_cflag = B38400 | CS8 | CREAD;
Alan Cox606d0992006-12-08 02:38:45 -0800580 pty_slave_driver->init_termios.c_ispeed = 38400;
581 pty_slave_driver->init_termios.c_ospeed = 38400;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700582 pty_slave_driver->other = pty_driver;
Linus Torvalds342a5972009-09-30 07:49:40 -0700583 tty_set_operations(pty_slave_driver, &slave_pty_ops_bsd);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700584
585 if (tty_register_driver(pty_driver))
586 panic("Couldn't register pty driver");
587 if (tty_register_driver(pty_slave_driver))
588 panic("Couldn't register pty slave driver");
589}
590#else
591static inline void legacy_pty_init(void) { }
592#endif
593
594/* Unix98 devices */
595#ifdef CONFIG_UNIX98_PTYS
Linus Torvalds1da177e2005-04-16 15:20:36 -0700596
Alan Coxd81ed102008-10-13 10:41:42 +0100597static struct cdev ptmx_cdev;
598
Alan Cox6caa76b2011-02-14 16:27:22 +0000599static int pty_unix98_ioctl(struct tty_struct *tty,
Linus Torvalds1da177e2005-04-16 15:20:36 -0700600 unsigned int cmd, unsigned long arg)
601{
602 switch (cmd) {
603 case TIOCSPTLCK: /* Set PT Lock (disallow slave open) */
604 return pty_set_lock(tty, (int __user *)arg);
Cyrill Gorcunov84fd7bd2012-10-24 23:43:22 +0400605 case TIOCGPTLCK: /* Get PT Lock status */
606 return pty_get_lock(tty, (int __user *)arg);
Cyrill Gorcunov06026d92012-10-24 23:43:20 +0400607 case TIOCPKT: /* Set PT packet mode */
608 return pty_set_pktmode(tty, (int __user *)arg);
Cyrill Gorcunov84fd7bd2012-10-24 23:43:22 +0400609 case TIOCGPKT: /* Get PT packet mode */
610 return pty_get_pktmode(tty, (int __user *)arg);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700611 case TIOCGPTN: /* Get PT Number */
612 return put_user(tty->index, (unsigned int __user *)arg);
hyc@symas.com26df6d12010-06-22 10:14:49 -0700613 case TIOCSIG: /* Send signal to other side of pty */
614 return pty_signal(tty, (int) arg);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700615 }
616
617 return -ENOIOCTLCMD;
618}
619
Alan Cox99f1fe12008-10-13 10:42:00 +0100620/**
621 * ptm_unix98_lookup - find a pty master
622 * @driver: ptm driver
623 * @idx: tty index
624 *
625 * Look up a pty master device. Called under the tty_mutex for now.
626 * This provides our locking.
627 */
628
Sukadev Bhattiprolu15f1a632008-10-13 10:42:59 +0100629static struct tty_struct *ptm_unix98_lookup(struct tty_driver *driver,
630 struct inode *ptm_inode, int idx)
Alan Cox99f1fe12008-10-13 10:42:00 +0100631{
Konstantin Khlebnikov593a27c2012-01-05 13:04:21 +0400632 /* Master must be open via /dev/ptmx */
633 return ERR_PTR(-EIO);
Alan Cox99f1fe12008-10-13 10:42:00 +0100634}
635
636/**
637 * pts_unix98_lookup - find a pty slave
638 * @driver: pts driver
639 * @idx: tty index
640 *
641 * Look up a pty master device. Called under the tty_mutex for now.
Alan Coxd739e652012-05-03 22:22:09 +0100642 * This provides our locking for the tty pointer.
Alan Cox99f1fe12008-10-13 10:42:00 +0100643 */
644
Sukadev Bhattiprolu15f1a632008-10-13 10:42:59 +0100645static struct tty_struct *pts_unix98_lookup(struct tty_driver *driver,
646 struct inode *pts_inode, int idx)
Alan Cox99f1fe12008-10-13 10:42:00 +0100647{
Alan Coxd739e652012-05-03 22:22:09 +0100648 struct tty_struct *tty;
649
650 mutex_lock(&devpts_mutex);
Jiri Slaby8fcbaa22012-10-18 22:26:27 +0200651 tty = devpts_get_priv(pts_inode);
Alan Coxd739e652012-05-03 22:22:09 +0100652 mutex_unlock(&devpts_mutex);
Alan Cox99f1fe12008-10-13 10:42:00 +0100653 /* Master must be open before slave */
654 if (!tty)
655 return ERR_PTR(-EIO);
656 return tty;
657}
658
Alan Cox8b0a88d2008-10-13 10:42:19 +0100659/* We have no need to install and remove our tty objects as devpts does all
660 the work for us */
661
Alan Coxbf970ee2008-10-13 10:42:39 +0100662static int pty_unix98_install(struct tty_driver *driver, struct tty_struct *tty)
Alan Cox8b0a88d2008-10-13 10:42:19 +0100663{
Jiri Slaby5d249bc2012-06-04 13:35:29 +0200664 return pty_common_install(driver, tty, false);
Alan Cox8b0a88d2008-10-13 10:42:19 +0100665}
666
Jiri Slaby71716042012-06-04 13:35:28 +0200667static void pty_unix98_remove(struct tty_driver *driver, struct tty_struct *tty)
Jiri Slaby484af542011-11-16 16:27:11 +0100668{
Alan Cox8b0a88d2008-10-13 10:42:19 +0100669}
670
Jiri Slabyf4b208e2013-04-15 07:52:05 +0200671/* this is called once with whichever end is closed last */
672static void pty_unix98_shutdown(struct tty_struct *tty)
673{
674 devpts_kill_index(tty->driver_data, tty->index);
675}
676
Alan Coxfeebed62008-10-13 10:41:30 +0100677static const struct tty_operations ptm_unix98_ops = {
Alan Cox99f1fe12008-10-13 10:42:00 +0100678 .lookup = ptm_unix98_lookup,
Alan Coxbf970ee2008-10-13 10:42:39 +0100679 .install = pty_unix98_install,
Jiri Slaby71716042012-06-04 13:35:28 +0200680 .remove = pty_unix98_remove,
Alan Cox3e8e88c2008-04-30 00:54:10 -0700681 .open = pty_open,
682 .close = pty_close,
683 .write = pty_write,
684 .write_room = pty_write_room,
685 .flush_buffer = pty_flush_buffer,
686 .chars_in_buffer = pty_chars_in_buffer,
687 .unthrottle = pty_unthrottle,
Alan Coxfeebed62008-10-13 10:41:30 +0100688 .ioctl = pty_unix98_ioctl,
Alan Cox36b3c072012-07-17 17:06:57 +0100689 .resize = pty_resize,
Jiri Slabyfa2ecfc5a2012-10-18 22:26:31 +0200690 .shutdown = pty_unix98_shutdown,
Alan Cox36b3c072012-07-17 17:06:57 +0100691 .cleanup = pty_cleanup
Alan Cox3e8e88c2008-04-30 00:54:10 -0700692};
693
Alan Cox99f1fe12008-10-13 10:42:00 +0100694static const struct tty_operations pty_unix98_ops = {
695 .lookup = pts_unix98_lookup,
Alan Coxbf970ee2008-10-13 10:42:39 +0100696 .install = pty_unix98_install,
Jiri Slaby71716042012-06-04 13:35:28 +0200697 .remove = pty_unix98_remove,
Alan Cox99f1fe12008-10-13 10:42:00 +0100698 .open = pty_open,
699 .close = pty_close,
700 .write = pty_write,
701 .write_room = pty_write_room,
702 .flush_buffer = pty_flush_buffer,
703 .chars_in_buffer = pty_chars_in_buffer,
704 .unthrottle = pty_unthrottle,
705 .set_termios = pty_set_termios,
Peter Hurley01adc802014-09-10 15:06:32 -0400706 .start = pty_start,
707 .stop = pty_stop,
Jiri Slabyfa2ecfc5a2012-10-18 22:26:31 +0200708 .shutdown = pty_unix98_shutdown,
Jiri Slabyd03702a2012-06-04 13:35:30 +0200709 .cleanup = pty_cleanup,
Alan Cox99f1fe12008-10-13 10:42:00 +0100710};
Alan Coxd81ed102008-10-13 10:41:42 +0100711
712/**
713 * ptmx_open - open a unix 98 pty master
714 * @inode: inode of device file
715 * @filp: file pointer to tty
716 *
717 * Allocate a unix98 pty master device from the ptmx driver.
718 *
719 * Locking: tty_mutex protects the init_dev work. tty->count should
Cong Dingb9f80332013-01-12 05:01:22 +0100720 * protect the rest.
Alan Coxd81ed102008-10-13 10:41:42 +0100721 * allocated_ptys_lock handles the list of free pty numbers
722 */
723
Arnd Bergmann64ba3dc32010-06-01 22:53:02 +0200724static int ptmx_open(struct inode *inode, struct file *filp)
Alan Coxd81ed102008-10-13 10:41:42 +0100725{
726 struct tty_struct *tty;
Jiri Slaby162b97c2012-10-18 22:26:28 +0200727 struct inode *slave_inode;
Alan Coxd81ed102008-10-13 10:41:42 +0100728 int retval;
729 int index;
730
731 nonseekable_open(inode, filp);
732
Linus Torvaldsb0b88562013-05-01 07:32:21 -0700733 /* We refuse fsnotify events on ptmx, since it's a shared resource */
734 filp->f_mode |= FMODE_NONOTIFY;
735
Jiri Slabyfa90e1c2011-10-12 11:32:43 +0200736 retval = tty_alloc_file(filp);
737 if (retval)
738 return retval;
739
Alan Coxd81ed102008-10-13 10:41:42 +0100740 /* find a device that is not in use. */
Alan Cox89c8d912012-08-08 16:30:13 +0100741 mutex_lock(&devpts_mutex);
Sukadev Bhattiprolu15f1a632008-10-13 10:42:59 +0100742 index = devpts_new_index(inode);
Jiri Slabyfa90e1c2011-10-12 11:32:43 +0200743 if (index < 0) {
744 retval = index;
Alan Cox05fb79e2012-09-19 15:34:47 +0100745 mutex_unlock(&devpts_mutex);
Jiri Slabyfa90e1c2011-10-12 11:32:43 +0200746 goto err_file;
747 }
Alan Coxd81ed102008-10-13 10:41:42 +0100748
Alan Cox6d31a882012-07-14 15:31:27 +0100749 mutex_unlock(&devpts_mutex);
Alan Cox89c8d912012-08-08 16:30:13 +0100750
751 mutex_lock(&tty_mutex);
752 tty = tty_init_dev(ptm_driver, index);
Alan Coxd81ed102008-10-13 10:41:42 +0100753
Alan Cox73ec06f2008-10-13 10:42:29 +0100754 if (IS_ERR(tty)) {
755 retval = PTR_ERR(tty);
Alan Coxd81ed102008-10-13 10:41:42 +0100756 goto out;
Alan Cox73ec06f2008-10-13 10:42:29 +0100757 }
Alan Coxd81ed102008-10-13 10:41:42 +0100758
Alan Cox89c8d912012-08-08 16:30:13 +0100759 /* The tty returned here is locked so we can safely
760 drop the mutex */
761 mutex_unlock(&tty_mutex);
762
Alan Coxd81ed102008-10-13 10:41:42 +0100763 set_bit(TTY_PTY_LOCK, &tty->flags); /* LOCK THE SLAVE */
Peter Hurley7acf6cd2013-01-30 12:43:49 -0500764 tty->driver_data = inode;
Nick Pigginee2ffa02010-08-18 04:37:35 +1000765
Jiri Slabyfa90e1c2011-10-12 11:32:43 +0200766 tty_add_file(tty, filp);
Alan Coxd81ed102008-10-13 10:41:42 +0100767
Jiri Slabyf11afb62012-10-18 22:26:29 +0200768 slave_inode = devpts_pty_new(inode,
769 MKDEV(UNIX98_PTY_SLAVE_MAJOR, index), index,
770 tty->link);
Jiri Slaby162b97c2012-10-18 22:26:28 +0200771 if (IS_ERR(slave_inode)) {
772 retval = PTR_ERR(slave_inode);
Jiri Slaby1177c0e2011-10-12 11:32:44 +0200773 goto err_release;
Jiri Slaby162b97c2012-10-18 22:26:28 +0200774 }
Peter Hurley7acf6cd2013-01-30 12:43:49 -0500775 tty->link->driver_data = slave_inode;
Alan Coxd81ed102008-10-13 10:41:42 +0100776
777 retval = ptm_driver->ops->open(tty, filp);
Arnd Bergmann64ba3dc32010-06-01 22:53:02 +0200778 if (retval)
Jiri Slaby1177c0e2011-10-12 11:32:44 +0200779 goto err_release;
780
Alan Cox89c8d912012-08-08 16:30:13 +0100781 tty_unlock(tty);
Jiri Slaby1177c0e2011-10-12 11:32:44 +0200782 return 0;
783err_release:
Alan Cox89c8d912012-08-08 16:30:13 +0100784 tty_unlock(tty);
Alan Coxeeb89d92009-11-30 13:18:29 +0000785 tty_release(inode, filp);
Alan Coxd81ed102008-10-13 10:41:42 +0100786 return retval;
787out:
Alan Cox89c8d912012-08-08 16:30:13 +0100788 mutex_unlock(&tty_mutex);
Jiri Slabyd3bda522012-01-30 21:14:32 +0100789 devpts_kill_index(inode, index);
Jiri Slabyfa90e1c2011-10-12 11:32:43 +0200790err_file:
791 tty_free_file(filp);
Arnd Bergmann64ba3dc32010-06-01 22:53:02 +0200792 return retval;
Alan Coxd81ed102008-10-13 10:41:42 +0100793}
794
795static struct file_operations ptmx_fops;
796
Linus Torvalds1da177e2005-04-16 15:20:36 -0700797static void __init unix98_pty_init(void)
798{
Jiri Slaby21aca2f2012-08-08 22:26:41 +0200799 ptm_driver = tty_alloc_driver(NR_UNIX98_PTY_MAX,
800 TTY_DRIVER_RESET_TERMIOS |
801 TTY_DRIVER_REAL_RAW |
802 TTY_DRIVER_DYNAMIC_DEV |
803 TTY_DRIVER_DEVPTS_MEM |
804 TTY_DRIVER_DYNAMIC_ALLOC);
Dan Carpenterc3a63442012-08-16 16:16:56 +0300805 if (IS_ERR(ptm_driver))
Linus Torvalds1da177e2005-04-16 15:20:36 -0700806 panic("Couldn't allocate Unix98 ptm driver");
Jiri Slaby21aca2f2012-08-08 22:26:41 +0200807 pts_driver = tty_alloc_driver(NR_UNIX98_PTY_MAX,
808 TTY_DRIVER_RESET_TERMIOS |
809 TTY_DRIVER_REAL_RAW |
810 TTY_DRIVER_DYNAMIC_DEV |
811 TTY_DRIVER_DEVPTS_MEM |
812 TTY_DRIVER_DYNAMIC_ALLOC);
Dan Carpenterc3a63442012-08-16 16:16:56 +0300813 if (IS_ERR(pts_driver))
Linus Torvalds1da177e2005-04-16 15:20:36 -0700814 panic("Couldn't allocate Unix98 pts driver");
815
Linus Torvalds1da177e2005-04-16 15:20:36 -0700816 ptm_driver->driver_name = "pty_master";
817 ptm_driver->name = "ptm";
818 ptm_driver->major = UNIX98_PTY_MASTER_MAJOR;
819 ptm_driver->minor_start = 0;
820 ptm_driver->type = TTY_DRIVER_TYPE_PTY;
821 ptm_driver->subtype = PTY_TYPE_MASTER;
822 ptm_driver->init_termios = tty_std_termios;
823 ptm_driver->init_termios.c_iflag = 0;
824 ptm_driver->init_termios.c_oflag = 0;
825 ptm_driver->init_termios.c_cflag = B38400 | CS8 | CREAD;
826 ptm_driver->init_termios.c_lflag = 0;
Alan Cox606d0992006-12-08 02:38:45 -0800827 ptm_driver->init_termios.c_ispeed = 38400;
828 ptm_driver->init_termios.c_ospeed = 38400;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700829 ptm_driver->other = pts_driver;
Alan Coxfeebed62008-10-13 10:41:30 +0100830 tty_set_operations(ptm_driver, &ptm_unix98_ops);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700831
Linus Torvalds1da177e2005-04-16 15:20:36 -0700832 pts_driver->driver_name = "pty_slave";
833 pts_driver->name = "pts";
834 pts_driver->major = UNIX98_PTY_SLAVE_MAJOR;
835 pts_driver->minor_start = 0;
836 pts_driver->type = TTY_DRIVER_TYPE_PTY;
837 pts_driver->subtype = PTY_TYPE_SLAVE;
838 pts_driver->init_termios = tty_std_termios;
839 pts_driver->init_termios.c_cflag = B38400 | CS8 | CREAD;
Alan Cox606d0992006-12-08 02:38:45 -0800840 pts_driver->init_termios.c_ispeed = 38400;
841 pts_driver->init_termios.c_ospeed = 38400;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700842 pts_driver->other = ptm_driver;
Alan Cox99f1fe12008-10-13 10:42:00 +0100843 tty_set_operations(pts_driver, &pty_unix98_ops);
Alan Coxfe9cd962008-10-13 10:43:38 +0100844
Linus Torvalds1da177e2005-04-16 15:20:36 -0700845 if (tty_register_driver(ptm_driver))
846 panic("Couldn't register Unix98 ptm driver");
847 if (tty_register_driver(pts_driver))
848 panic("Couldn't register Unix98 pts driver");
849
Alan Coxd81ed102008-10-13 10:41:42 +0100850 /* Now create the /dev/ptmx special device */
851 tty_default_fops(&ptmx_fops);
852 ptmx_fops.open = ptmx_open;
853
854 cdev_init(&ptmx_cdev, &ptmx_fops);
855 if (cdev_add(&ptmx_cdev, MKDEV(TTYAUX_MAJOR, 2), 1) ||
856 register_chrdev_region(MKDEV(TTYAUX_MAJOR, 2), 1, "/dev/ptmx") < 0)
Cong Ding82f8c352013-01-12 05:01:21 +0100857 panic("Couldn't register /dev/ptmx driver");
Alan Coxd81ed102008-10-13 10:41:42 +0100858 device_create(tty_class, NULL, MKDEV(TTYAUX_MAJOR, 2), NULL, "ptmx");
Linus Torvalds1da177e2005-04-16 15:20:36 -0700859}
Alan Coxd81ed102008-10-13 10:41:42 +0100860
Linus Torvalds1da177e2005-04-16 15:20:36 -0700861#else
862static inline void unix98_pty_init(void) { }
863#endif
864
865static int __init pty_init(void)
866{
867 legacy_pty_init();
868 unix98_pty_init();
869 return 0;
870}
871module_init(pty_init);