Commit | Line | Data |
---|---|---|
1da177e4 | 1 | /* |
1da177e4 LT |
2 | * 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 | |
1da177e4 | 6 | * |
1da177e4 LT |
7 | */ |
8 | ||
fe9cd962 | 9 | #include <linux/module.h> |
1da177e4 LT |
10 | |
11 | #include <linux/errno.h> | |
1da177e4 LT |
12 | #include <linux/interrupt.h> |
13 | #include <linux/tty.h> | |
14 | #include <linux/tty_flip.h> | |
15 | #include <linux/fcntl.h> | |
d43c36dc | 16 | #include <linux/sched.h> |
1da177e4 LT |
17 | #include <linux/string.h> |
18 | #include <linux/major.h> | |
19 | #include <linux/mm.h> | |
20 | #include <linux/init.h> | |
d81ed103 | 21 | #include <linux/device.h> |
fe9cd962 | 22 | #include <linux/uaccess.h> |
1da177e4 LT |
23 | #include <linux/bitops.h> |
24 | #include <linux/devpts_fs.h> | |
5a0e3ad6 | 25 | #include <linux/slab.h> |
d739e65b | 26 | #include <linux/mutex.h> |
01adc807 | 27 | #include <linux/poll.h> |
1da177e4 | 28 | |
fe9cd962 | 29 | |
1da177e4 | 30 | #ifdef CONFIG_UNIX98_PTYS |
da2bdf9a | 31 | static struct tty_driver *ptm_driver; |
1da177e4 | 32 | static struct tty_driver *pts_driver; |
d739e65b | 33 | static DEFINE_MUTEX(devpts_mutex); |
1da177e4 LT |
34 | #endif |
35 | ||
fe9cd962 | 36 | static void pty_close(struct tty_struct *tty, struct file *filp) |
1da177e4 | 37 | { |
fe9cd962 AC |
38 | BUG_ON(!tty); |
39 | if (tty->driver->subtype == PTY_TYPE_MASTER) | |
40 | WARN_ON(tty->count > 1); | |
41 | else { | |
69939035 PH |
42 | if (test_bit(TTY_IO_ERROR, &tty->flags)) |
43 | return; | |
1da177e4 LT |
44 | if (tty->count > 2) |
45 | return; | |
46 | } | |
69939035 | 47 | set_bit(TTY_IO_ERROR, &tty->flags); |
1da177e4 LT |
48 | wake_up_interruptible(&tty->read_wait); |
49 | wake_up_interruptible(&tty->write_wait); | |
4ed60fc2 | 50 | spin_lock_irq(&tty->ctrl_lock); |
1da177e4 | 51 | tty->packet = 0; |
4ed60fc2 | 52 | spin_unlock_irq(&tty->ctrl_lock); |
89c8d91e | 53 | /* Review - krefs on tty_link ?? */ |
1da177e4 LT |
54 | if (!tty->link) |
55 | return; | |
52bce7f8 | 56 | tty_flush_to_ldisc(tty->link); |
1da177e4 LT |
57 | set_bit(TTY_OTHER_CLOSED, &tty->link->flags); |
58 | wake_up_interruptible(&tty->link->read_wait); | |
59 | wake_up_interruptible(&tty->link->write_wait); | |
60 | if (tty->driver->subtype == PTY_TYPE_MASTER) { | |
61 | set_bit(TTY_OTHER_CLOSED, &tty->flags); | |
ce1000dd | 62 | #ifdef CONFIG_UNIX98_PTYS |
d739e65b | 63 | if (tty->driver == ptm_driver) { |
b9f8033f | 64 | mutex_lock(&devpts_mutex); |
7acf6cd8 PH |
65 | if (tty->link->driver_data) |
66 | devpts_pty_kill(tty->link->driver_data); | |
b9f8033f | 67 | mutex_unlock(&devpts_mutex); |
d739e65b | 68 | } |
ce1000dd | 69 | #endif |
11dbf203 | 70 | tty_vhangup(tty->link); |
1da177e4 LT |
71 | } |
72 | } | |
73 | ||
74 | /* | |
75 | * The unthrottle routine is called by the line discipline to signal | |
76 | * that it can receive more characters. For PTY's, the TTY_THROTTLED | |
77 | * flag is always set, to force the line discipline to always call the | |
fe9cd962 | 78 | * unthrottle routine when there are fewer than TTY_THRESHOLD_UNTHROTTLE |
1da177e4 LT |
79 | * characters in the queue. This is necessary since each time this |
80 | * happens, we need to wake up any sleeping processes that could be | |
81 | * (1) trying to send data to the pty, or (2) waiting in wait_until_sent() | |
82 | * for the pty buffer to be drained. | |
83 | */ | |
fe9cd962 | 84 | static void pty_unthrottle(struct tty_struct *tty) |
1da177e4 | 85 | { |
d945cb9c | 86 | tty_wakeup(tty->link); |
1da177e4 LT |
87 | set_bit(TTY_THROTTLED, &tty->flags); |
88 | } | |
89 | ||
d945cb9c AC |
90 | /** |
91 | * pty_write - write to a pty | |
92 | * @tty: the tty we write from | |
93 | * @buf: kernel buffer of data | |
94 | * @count: bytes to write | |
762faaed | 95 | * |
d945cb9c AC |
96 | * Our "hardware" write method. Data is coming from the ldisc which |
97 | * may be in a non sleeping state. We simply throw this at the other | |
98 | * end of the link as if we were an IRQ handler receiving stuff for | |
99 | * the other side of the pty/tty pair. | |
1da177e4 | 100 | */ |
d945cb9c | 101 | |
ac89a917 | 102 | static int pty_write(struct tty_struct *tty, const unsigned char *buf, int c) |
1da177e4 LT |
103 | { |
104 | struct tty_struct *to = tty->link; | |
1da177e4 | 105 | |
d945cb9c | 106 | if (tty->stopped) |
1da177e4 | 107 | return 0; |
d945cb9c | 108 | |
d945cb9c AC |
109 | if (c > 0) { |
110 | /* Stuff the data into the input queue of the other end */ | |
05c7cd39 | 111 | c = tty_insert_flip_string(to->port, buf, c); |
d945cb9c | 112 | /* And shovel */ |
5ede5253 | 113 | if (c) |
2e124b4a | 114 | tty_flip_buffer_push(to->port); |
762faaed | 115 | } |
1da177e4 LT |
116 | return c; |
117 | } | |
118 | ||
d945cb9c AC |
119 | /** |
120 | * pty_write_room - write space | |
121 | * @tty: tty we are writing from | |
122 | * | |
123 | * Report how many bytes the ldisc can send into the queue for | |
124 | * the other device. | |
125 | */ | |
126 | ||
1da177e4 LT |
127 | static int pty_write_room(struct tty_struct *tty) |
128 | { | |
85dfd81d LT |
129 | if (tty->stopped) |
130 | return 0; | |
c81622ac | 131 | return tty_buffer_space_avail(tty->link->port); |
1da177e4 LT |
132 | } |
133 | ||
d945cb9c AC |
134 | /** |
135 | * pty_chars_in_buffer - characters currently in our tx queue | |
136 | * @tty: our tty | |
fe9cd962 | 137 | * |
d945cb9c AC |
138 | * Report how much we have in the transmit queue. As everything is |
139 | * instantly at the other end this is easy to implement. | |
1da177e4 | 140 | */ |
d945cb9c | 141 | |
1da177e4 LT |
142 | static int pty_chars_in_buffer(struct tty_struct *tty) |
143 | { | |
d945cb9c | 144 | return 0; |
1da177e4 LT |
145 | } |
146 | ||
147 | /* Set the lock flag on a pty */ | |
fe9cd962 | 148 | static int pty_set_lock(struct tty_struct *tty, int __user *arg) |
1da177e4 LT |
149 | { |
150 | int val; | |
fe9cd962 | 151 | if (get_user(val, arg)) |
1da177e4 LT |
152 | return -EFAULT; |
153 | if (val) | |
154 | set_bit(TTY_PTY_LOCK, &tty->flags); | |
155 | else | |
156 | clear_bit(TTY_PTY_LOCK, &tty->flags); | |
157 | return 0; | |
158 | } | |
159 | ||
84fd7bdf CG |
160 | static int pty_get_lock(struct tty_struct *tty, int __user *arg) |
161 | { | |
162 | int locked = test_bit(TTY_PTY_LOCK, &tty->flags); | |
163 | return put_user(locked, arg); | |
164 | } | |
165 | ||
06026d91 CG |
166 | /* Set the packet mode on a pty */ |
167 | static int pty_set_pktmode(struct tty_struct *tty, int __user *arg) | |
168 | { | |
06026d91 CG |
169 | int pktmode; |
170 | ||
171 | if (get_user(pktmode, arg)) | |
172 | return -EFAULT; | |
173 | ||
6054c16e | 174 | spin_lock_irq(&tty->ctrl_lock); |
06026d91 CG |
175 | if (pktmode) { |
176 | if (!tty->packet) { | |
06026d91 | 177 | tty->link->ctrl_status = 0; |
2622d73e PH |
178 | smp_mb(); |
179 | tty->packet = 1; | |
06026d91 CG |
180 | } |
181 | } else | |
182 | tty->packet = 0; | |
6054c16e | 183 | spin_unlock_irq(&tty->ctrl_lock); |
06026d91 CG |
184 | |
185 | return 0; | |
186 | } | |
187 | ||
84fd7bdf CG |
188 | /* Get the packet mode of a pty */ |
189 | static int pty_get_pktmode(struct tty_struct *tty, int __user *arg) | |
190 | { | |
191 | int pktmode = tty->packet; | |
192 | return put_user(pktmode, arg); | |
193 | } | |
194 | ||
26df6d13 | 195 | /* Send a signal to the slave */ |
196 | static int pty_signal(struct tty_struct *tty, int sig) | |
197 | { | |
26df6d13 | 198 | struct pid *pgrp; |
199 | ||
37480a05 PH |
200 | if (sig != SIGINT && sig != SIGQUIT && sig != SIGTSTP) |
201 | return -EINVAL; | |
202 | ||
26df6d13 | 203 | if (tty->link) { |
5b239542 PH |
204 | pgrp = tty_get_pgrp(tty->link); |
205 | if (pgrp) | |
206 | kill_pgrp(pgrp, sig, 1); | |
26df6d13 | 207 | put_pid(pgrp); |
208 | } | |
209 | return 0; | |
210 | } | |
211 | ||
1da177e4 LT |
212 | static void pty_flush_buffer(struct tty_struct *tty) |
213 | { | |
214 | struct tty_struct *to = tty->link; | |
fe9cd962 | 215 | |
1da177e4 LT |
216 | if (!to) |
217 | return; | |
d945cb9c | 218 | /* tty_buffer_flush(to); FIXME */ |
1da177e4 | 219 | if (to->packet) { |
6054c16e | 220 | spin_lock_irq(&tty->ctrl_lock); |
1da177e4 LT |
221 | tty->ctrl_status |= TIOCPKT_FLUSHWRITE; |
222 | wake_up_interruptible(&to->read_wait); | |
6054c16e | 223 | spin_unlock_irq(&tty->ctrl_lock); |
1da177e4 LT |
224 | } |
225 | } | |
226 | ||
fe9cd962 | 227 | static int pty_open(struct tty_struct *tty, struct file *filp) |
1da177e4 | 228 | { |
1da177e4 | 229 | if (!tty || !tty->link) |
7c61c3d8 | 230 | return -ENODEV; |
69939035 | 231 | |
1da177e4 LT |
232 | if (test_bit(TTY_OTHER_CLOSED, &tty->flags)) |
233 | goto out; | |
234 | if (test_bit(TTY_PTY_LOCK, &tty->link->flags)) | |
235 | goto out; | |
80cace72 | 236 | if (tty->driver->subtype == PTY_TYPE_SLAVE && tty->link->count != 1) |
1da177e4 LT |
237 | goto out; |
238 | ||
69939035 | 239 | clear_bit(TTY_IO_ERROR, &tty->flags); |
1da177e4 LT |
240 | clear_bit(TTY_OTHER_CLOSED, &tty->link->flags); |
241 | set_bit(TTY_THROTTLED, &tty->flags); | |
7c61c3d8 PH |
242 | return 0; |
243 | ||
1da177e4 | 244 | out: |
7c61c3d8 PH |
245 | set_bit(TTY_IO_ERROR, &tty->flags); |
246 | return -EIO; | |
1da177e4 LT |
247 | } |
248 | ||
fe9cd962 AC |
249 | static void pty_set_termios(struct tty_struct *tty, |
250 | struct ktermios *old_termios) | |
1da177e4 | 251 | { |
dbfcd851 PH |
252 | /* See if packet mode change of state. */ |
253 | if (tty->link && tty->link->packet) { | |
254 | int extproc = (old_termios->c_lflag & EXTPROC) | | |
255 | (tty->termios.c_lflag & EXTPROC); | |
256 | int old_flow = ((old_termios->c_iflag & IXON) && | |
257 | (old_termios->c_cc[VSTOP] == '\023') && | |
258 | (old_termios->c_cc[VSTART] == '\021')); | |
259 | int new_flow = (I_IXON(tty) && | |
260 | STOP_CHAR(tty) == '\023' && | |
261 | START_CHAR(tty) == '\021'); | |
262 | if ((old_flow != new_flow) || extproc) { | |
4d8c1dff | 263 | spin_lock_irq(&tty->ctrl_lock); |
dbfcd851 PH |
264 | if (old_flow != new_flow) { |
265 | tty->ctrl_status &= ~(TIOCPKT_DOSTOP | TIOCPKT_NOSTOP); | |
266 | if (new_flow) | |
267 | tty->ctrl_status |= TIOCPKT_DOSTOP; | |
268 | else | |
269 | tty->ctrl_status |= TIOCPKT_NOSTOP; | |
270 | } | |
271 | if (extproc) | |
272 | tty->ctrl_status |= TIOCPKT_IOCTL; | |
4d8c1dff | 273 | spin_unlock_irq(&tty->ctrl_lock); |
dbfcd851 PH |
274 | wake_up_interruptible(&tty->link->read_wait); |
275 | } | |
276 | } | |
277 | ||
adc8d746 AC |
278 | tty->termios.c_cflag &= ~(CSIZE | PARENB); |
279 | tty->termios.c_cflag |= (CS8 | CREAD); | |
1da177e4 LT |
280 | } |
281 | ||
fc6f6238 AC |
282 | /** |
283 | * pty_do_resize - resize event | |
284 | * @tty: tty being resized | |
c774bda2 | 285 | * @ws: window size being set. |
fc6f6238 | 286 | * |
3ad2f3fb | 287 | * Update the termios variables and send the necessary signals to |
fc6f6238 AC |
288 | * peform a terminal resize correctly |
289 | */ | |
290 | ||
159a8e92 | 291 | static int pty_resize(struct tty_struct *tty, struct winsize *ws) |
fc6f6238 AC |
292 | { |
293 | struct pid *pgrp, *rpgrp; | |
fc6f6238 AC |
294 | struct tty_struct *pty = tty->link; |
295 | ||
296 | /* For a PTY we need to lock the tty side */ | |
dee4a0be | 297 | mutex_lock(&tty->winsize_mutex); |
fc6f6238 AC |
298 | if (!memcmp(ws, &tty->winsize, sizeof(*ws))) |
299 | goto done; | |
300 | ||
5b239542 PH |
301 | /* Signal the foreground process group of both ptys */ |
302 | pgrp = tty_get_pgrp(tty); | |
303 | rpgrp = tty_get_pgrp(pty); | |
fc6f6238 AC |
304 | |
305 | if (pgrp) | |
306 | kill_pgrp(pgrp, SIGWINCH, 1); | |
307 | if (rpgrp != pgrp && rpgrp) | |
308 | kill_pgrp(rpgrp, SIGWINCH, 1); | |
309 | ||
310 | put_pid(pgrp); | |
311 | put_pid(rpgrp); | |
312 | ||
313 | tty->winsize = *ws; | |
314 | pty->winsize = *ws; /* Never used so will go away soon */ | |
315 | done: | |
dee4a0be | 316 | mutex_unlock(&tty->winsize_mutex); |
fc6f6238 AC |
317 | return 0; |
318 | } | |
319 | ||
01adc807 PH |
320 | /** |
321 | * pty_start - start() handler | |
322 | * pty_stop - stop() handler | |
323 | * @tty: tty being flow-controlled | |
324 | * | |
325 | * Propagates the TIOCPKT status to the master pty. | |
326 | * | |
327 | * NB: only the master pty can be in packet mode so only the slave | |
328 | * needs start()/stop() handlers | |
329 | */ | |
330 | static void pty_start(struct tty_struct *tty) | |
331 | { | |
332 | unsigned long flags; | |
333 | ||
01adc807 | 334 | if (tty->link && tty->link->packet) { |
54e8e5fc | 335 | spin_lock_irqsave(&tty->ctrl_lock, flags); |
01adc807 PH |
336 | tty->ctrl_status &= ~TIOCPKT_STOP; |
337 | tty->ctrl_status |= TIOCPKT_START; | |
54e8e5fc | 338 | spin_unlock_irqrestore(&tty->ctrl_lock, flags); |
01adc807 PH |
339 | wake_up_interruptible_poll(&tty->link->read_wait, POLLIN); |
340 | } | |
01adc807 PH |
341 | } |
342 | ||
343 | static void pty_stop(struct tty_struct *tty) | |
344 | { | |
345 | unsigned long flags; | |
346 | ||
01adc807 | 347 | if (tty->link && tty->link->packet) { |
54e8e5fc | 348 | spin_lock_irqsave(&tty->ctrl_lock, flags); |
01adc807 PH |
349 | tty->ctrl_status &= ~TIOCPKT_START; |
350 | tty->ctrl_status |= TIOCPKT_STOP; | |
54e8e5fc | 351 | spin_unlock_irqrestore(&tty->ctrl_lock, flags); |
01adc807 PH |
352 | wake_up_interruptible_poll(&tty->link->read_wait, POLLIN); |
353 | } | |
01adc807 PH |
354 | } |
355 | ||
d155255a AC |
356 | /** |
357 | * pty_common_install - set up the pty pair | |
358 | * @driver: the pty driver | |
359 | * @tty: the tty being instantiated | |
2c964a2f | 360 | * @legacy: true if this is BSD style |
d155255a AC |
361 | * |
362 | * Perform the initial set up for the tty/pty pair. Called from the | |
363 | * tty layer when the port is first opened. | |
364 | * | |
365 | * Locking: the caller must hold the tty_mutex | |
366 | */ | |
5d249bc6 JS |
367 | static int pty_common_install(struct tty_driver *driver, struct tty_struct *tty, |
368 | bool legacy) | |
bf970ee4 AC |
369 | { |
370 | struct tty_struct *o_tty; | |
d03702a2 | 371 | struct tty_port *ports[2]; |
bf970ee4 | 372 | int idx = tty->index; |
5d249bc6 | 373 | int retval = -ENOMEM; |
bf970ee4 | 374 | |
55199ea3 PH |
375 | /* Opening the slave first has always returned -EIO */ |
376 | if (driver->subtype != PTY_TYPE_MASTER) | |
377 | return -EIO; | |
378 | ||
d03702a2 JS |
379 | ports[0] = kmalloc(sizeof **ports, GFP_KERNEL); |
380 | ports[1] = kmalloc(sizeof **ports, GFP_KERNEL); | |
6f9ea7ad | 381 | if (!ports[0] || !ports[1]) |
2c964a2f | 382 | goto err; |
bf970ee4 AC |
383 | if (!try_module_get(driver->other->owner)) { |
384 | /* This cannot in fact currently happen */ | |
2c964a2f | 385 | goto err; |
bf970ee4 | 386 | } |
2c964a2f RV |
387 | o_tty = alloc_tty_struct(driver->other, idx); |
388 | if (!o_tty) | |
389 | goto err_put_module; | |
bf970ee4 | 390 | |
2febdb63 PH |
391 | tty_set_lock_subclass(o_tty); |
392 | ||
5d249bc6 JS |
393 | if (legacy) { |
394 | /* We always use new tty termios data so we can do this | |
395 | the easy way .. */ | |
396 | retval = tty_init_termios(tty); | |
397 | if (retval) | |
398 | goto err_deinit_tty; | |
399 | ||
400 | retval = tty_init_termios(o_tty); | |
401 | if (retval) | |
402 | goto err_free_termios; | |
403 | ||
404 | driver->other->ttys[idx] = o_tty; | |
405 | driver->ttys[idx] = tty; | |
406 | } else { | |
adc8d746 AC |
407 | memset(&tty->termios_locked, 0, sizeof(tty->termios_locked)); |
408 | tty->termios = driver->init_termios; | |
409 | memset(&o_tty->termios_locked, 0, sizeof(tty->termios_locked)); | |
410 | o_tty->termios = driver->other->init_termios; | |
5d249bc6 | 411 | } |
fe9cd962 | 412 | |
bf970ee4 AC |
413 | /* |
414 | * Everything allocated ... set up the o_tty structure. | |
415 | */ | |
bf970ee4 | 416 | tty_driver_kref_get(driver->other); |
bf970ee4 AC |
417 | /* Establish the links in both directions */ |
418 | tty->link = o_tty; | |
419 | o_tty->link = tty; | |
d03702a2 JS |
420 | tty_port_init(ports[0]); |
421 | tty_port_init(ports[1]); | |
c81622ac PH |
422 | tty_buffer_set_limit(ports[0], 8192); |
423 | tty_buffer_set_limit(ports[1], 8192); | |
d03702a2 JS |
424 | o_tty->port = ports[0]; |
425 | tty->port = ports[1]; | |
967fab69 | 426 | o_tty->port->itty = o_tty; |
bf970ee4 AC |
427 | |
428 | tty_driver_kref_get(driver); | |
429 | tty->count++; | |
55199ea3 | 430 | o_tty->count++; |
bf970ee4 | 431 | return 0; |
8a1b8d70 | 432 | err_free_termios: |
5d249bc6 JS |
433 | if (legacy) |
434 | tty_free_termios(tty); | |
a9dccddb JS |
435 | err_deinit_tty: |
436 | deinitialize_tty_struct(o_tty); | |
2c964a2f RV |
437 | free_tty_struct(o_tty); |
438 | err_put_module: | |
07584d4a | 439 | module_put(driver->other->owner); |
2c964a2f | 440 | err: |
d03702a2 JS |
441 | kfree(ports[0]); |
442 | kfree(ports[1]); | |
8a1b8d70 | 443 | return retval; |
bf970ee4 AC |
444 | } |
445 | ||
d03702a2 JS |
446 | static void pty_cleanup(struct tty_struct *tty) |
447 | { | |
81c79838 | 448 | tty_port_put(tty->port); |
d03702a2 JS |
449 | } |
450 | ||
5d249bc6 JS |
451 | /* Traditional BSD devices */ |
452 | #ifdef CONFIG_LEGACY_PTYS | |
453 | ||
454 | static int pty_install(struct tty_driver *driver, struct tty_struct *tty) | |
455 | { | |
456 | return pty_common_install(driver, tty, true); | |
457 | } | |
458 | ||
d155255a AC |
459 | static void pty_remove(struct tty_driver *driver, struct tty_struct *tty) |
460 | { | |
461 | struct tty_struct *pair = tty->link; | |
462 | driver->ttys[tty->index] = NULL; | |
463 | if (pair) | |
464 | pair->driver->ttys[pair->index] = NULL; | |
465 | } | |
466 | ||
6caa76b7 | 467 | static int pty_bsd_ioctl(struct tty_struct *tty, |
1da177e4 LT |
468 | unsigned int cmd, unsigned long arg) |
469 | { | |
470 | switch (cmd) { | |
471 | case TIOCSPTLCK: /* Set PT Lock (disallow slave open) */ | |
472 | return pty_set_lock(tty, (int __user *) arg); | |
84fd7bdf CG |
473 | case TIOCGPTLCK: /* Get PT Lock status */ |
474 | return pty_get_lock(tty, (int __user *)arg); | |
06026d91 CG |
475 | case TIOCPKT: /* Set PT packet mode */ |
476 | return pty_set_pktmode(tty, (int __user *)arg); | |
84fd7bdf CG |
477 | case TIOCGPKT: /* Get PT packet mode */ |
478 | return pty_get_pktmode(tty, (int __user *)arg); | |
26df6d13 | 479 | case TIOCSIG: /* Send signal to other side of pty */ |
480 | return pty_signal(tty, (int) arg); | |
ded2f295 JS |
481 | case TIOCGPTN: /* TTY returns ENOTTY, but glibc expects EINVAL here */ |
482 | return -EINVAL; | |
1da177e4 LT |
483 | } |
484 | return -ENOIOCTLCMD; | |
485 | } | |
486 | ||
dc8c8587 KS |
487 | static int legacy_count = CONFIG_LEGACY_PTY_COUNT; |
488 | module_param(legacy_count, int, 0); | |
489 | ||
342a5971 LT |
490 | /* |
491 | * The master side of a pty can do TIOCSPTLCK and thus | |
492 | * has pty_bsd_ioctl. | |
493 | */ | |
494 | static const struct tty_operations master_pty_ops_bsd = { | |
495 | .install = pty_install, | |
3e8e88ca AC |
496 | .open = pty_open, |
497 | .close = pty_close, | |
498 | .write = pty_write, | |
499 | .write_room = pty_write_room, | |
500 | .flush_buffer = pty_flush_buffer, | |
501 | .chars_in_buffer = pty_chars_in_buffer, | |
502 | .unthrottle = pty_unthrottle, | |
3e8e88ca | 503 | .ioctl = pty_bsd_ioctl, |
d03702a2 | 504 | .cleanup = pty_cleanup, |
d155255a AC |
505 | .resize = pty_resize, |
506 | .remove = pty_remove | |
3e8e88ca AC |
507 | }; |
508 | ||
342a5971 LT |
509 | static const struct tty_operations slave_pty_ops_bsd = { |
510 | .install = pty_install, | |
511 | .open = pty_open, | |
512 | .close = pty_close, | |
513 | .write = pty_write, | |
514 | .write_room = pty_write_room, | |
515 | .flush_buffer = pty_flush_buffer, | |
516 | .chars_in_buffer = pty_chars_in_buffer, | |
517 | .unthrottle = pty_unthrottle, | |
518 | .set_termios = pty_set_termios, | |
d03702a2 | 519 | .cleanup = pty_cleanup, |
d155255a | 520 | .resize = pty_resize, |
01adc807 PH |
521 | .start = pty_start, |
522 | .stop = pty_stop, | |
d155255a | 523 | .remove = pty_remove |
342a5971 LT |
524 | }; |
525 | ||
1da177e4 LT |
526 | static void __init legacy_pty_init(void) |
527 | { | |
342a5971 LT |
528 | struct tty_driver *pty_driver, *pty_slave_driver; |
529 | ||
dc8c8587 KS |
530 | if (legacy_count <= 0) |
531 | return; | |
1da177e4 | 532 | |
21aca2fa JS |
533 | pty_driver = tty_alloc_driver(legacy_count, |
534 | TTY_DRIVER_RESET_TERMIOS | | |
535 | TTY_DRIVER_REAL_RAW | | |
536 | TTY_DRIVER_DYNAMIC_ALLOC); | |
c3a6344a | 537 | if (IS_ERR(pty_driver)) |
1da177e4 LT |
538 | panic("Couldn't allocate pty driver"); |
539 | ||
21aca2fa JS |
540 | pty_slave_driver = tty_alloc_driver(legacy_count, |
541 | TTY_DRIVER_RESET_TERMIOS | | |
542 | TTY_DRIVER_REAL_RAW | | |
543 | TTY_DRIVER_DYNAMIC_ALLOC); | |
c3a6344a | 544 | if (IS_ERR(pty_slave_driver)) |
1da177e4 LT |
545 | panic("Couldn't allocate pty slave driver"); |
546 | ||
1da177e4 LT |
547 | pty_driver->driver_name = "pty_master"; |
548 | pty_driver->name = "pty"; | |
1da177e4 LT |
549 | pty_driver->major = PTY_MASTER_MAJOR; |
550 | pty_driver->minor_start = 0; | |
551 | pty_driver->type = TTY_DRIVER_TYPE_PTY; | |
552 | pty_driver->subtype = PTY_TYPE_MASTER; | |
553 | pty_driver->init_termios = tty_std_termios; | |
554 | pty_driver->init_termios.c_iflag = 0; | |
555 | pty_driver->init_termios.c_oflag = 0; | |
556 | pty_driver->init_termios.c_cflag = B38400 | CS8 | CREAD; | |
557 | pty_driver->init_termios.c_lflag = 0; | |
606d099c AC |
558 | pty_driver->init_termios.c_ispeed = 38400; |
559 | pty_driver->init_termios.c_ospeed = 38400; | |
1da177e4 | 560 | pty_driver->other = pty_slave_driver; |
342a5971 | 561 | tty_set_operations(pty_driver, &master_pty_ops_bsd); |
1da177e4 | 562 | |
1da177e4 LT |
563 | pty_slave_driver->driver_name = "pty_slave"; |
564 | pty_slave_driver->name = "ttyp"; | |
1da177e4 LT |
565 | pty_slave_driver->major = PTY_SLAVE_MAJOR; |
566 | pty_slave_driver->minor_start = 0; | |
567 | pty_slave_driver->type = TTY_DRIVER_TYPE_PTY; | |
568 | pty_slave_driver->subtype = PTY_TYPE_SLAVE; | |
569 | pty_slave_driver->init_termios = tty_std_termios; | |
570 | pty_slave_driver->init_termios.c_cflag = B38400 | CS8 | CREAD; | |
606d099c AC |
571 | pty_slave_driver->init_termios.c_ispeed = 38400; |
572 | pty_slave_driver->init_termios.c_ospeed = 38400; | |
1da177e4 | 573 | pty_slave_driver->other = pty_driver; |
342a5971 | 574 | tty_set_operations(pty_slave_driver, &slave_pty_ops_bsd); |
1da177e4 LT |
575 | |
576 | if (tty_register_driver(pty_driver)) | |
577 | panic("Couldn't register pty driver"); | |
578 | if (tty_register_driver(pty_slave_driver)) | |
579 | panic("Couldn't register pty slave driver"); | |
580 | } | |
581 | #else | |
582 | static inline void legacy_pty_init(void) { } | |
583 | #endif | |
584 | ||
585 | /* Unix98 devices */ | |
586 | #ifdef CONFIG_UNIX98_PTYS | |
1da177e4 | 587 | |
d81ed103 AC |
588 | static struct cdev ptmx_cdev; |
589 | ||
6caa76b7 | 590 | static int pty_unix98_ioctl(struct tty_struct *tty, |
1da177e4 LT |
591 | unsigned int cmd, unsigned long arg) |
592 | { | |
593 | switch (cmd) { | |
594 | case TIOCSPTLCK: /* Set PT Lock (disallow slave open) */ | |
595 | return pty_set_lock(tty, (int __user *)arg); | |
84fd7bdf CG |
596 | case TIOCGPTLCK: /* Get PT Lock status */ |
597 | return pty_get_lock(tty, (int __user *)arg); | |
06026d91 CG |
598 | case TIOCPKT: /* Set PT packet mode */ |
599 | return pty_set_pktmode(tty, (int __user *)arg); | |
84fd7bdf CG |
600 | case TIOCGPKT: /* Get PT packet mode */ |
601 | return pty_get_pktmode(tty, (int __user *)arg); | |
1da177e4 LT |
602 | case TIOCGPTN: /* Get PT Number */ |
603 | return put_user(tty->index, (unsigned int __user *)arg); | |
26df6d13 | 604 | case TIOCSIG: /* Send signal to other side of pty */ |
605 | return pty_signal(tty, (int) arg); | |
1da177e4 LT |
606 | } |
607 | ||
608 | return -ENOIOCTLCMD; | |
609 | } | |
610 | ||
99f1fe18 AC |
611 | /** |
612 | * ptm_unix98_lookup - find a pty master | |
613 | * @driver: ptm driver | |
614 | * @idx: tty index | |
615 | * | |
616 | * Look up a pty master device. Called under the tty_mutex for now. | |
617 | * This provides our locking. | |
618 | */ | |
619 | ||
15f1a633 SB |
620 | static struct tty_struct *ptm_unix98_lookup(struct tty_driver *driver, |
621 | struct inode *ptm_inode, int idx) | |
99f1fe18 | 622 | { |
593a27c4 KK |
623 | /* Master must be open via /dev/ptmx */ |
624 | return ERR_PTR(-EIO); | |
99f1fe18 AC |
625 | } |
626 | ||
627 | /** | |
628 | * pts_unix98_lookup - find a pty slave | |
629 | * @driver: pts driver | |
630 | * @idx: tty index | |
631 | * | |
632 | * Look up a pty master device. Called under the tty_mutex for now. | |
d739e65b | 633 | * This provides our locking for the tty pointer. |
99f1fe18 AC |
634 | */ |
635 | ||
15f1a633 SB |
636 | static struct tty_struct *pts_unix98_lookup(struct tty_driver *driver, |
637 | struct inode *pts_inode, int idx) | |
99f1fe18 | 638 | { |
d739e65b AC |
639 | struct tty_struct *tty; |
640 | ||
641 | mutex_lock(&devpts_mutex); | |
8fcbaa2b | 642 | tty = devpts_get_priv(pts_inode); |
d739e65b | 643 | mutex_unlock(&devpts_mutex); |
99f1fe18 AC |
644 | /* Master must be open before slave */ |
645 | if (!tty) | |
646 | return ERR_PTR(-EIO); | |
647 | return tty; | |
648 | } | |
649 | ||
8b0a88d5 AC |
650 | /* We have no need to install and remove our tty objects as devpts does all |
651 | the work for us */ | |
652 | ||
bf970ee4 | 653 | static int pty_unix98_install(struct tty_driver *driver, struct tty_struct *tty) |
8b0a88d5 | 654 | { |
5d249bc6 | 655 | return pty_common_install(driver, tty, false); |
8b0a88d5 AC |
656 | } |
657 | ||
7171604a | 658 | static void pty_unix98_remove(struct tty_driver *driver, struct tty_struct *tty) |
8b0a88d5 AC |
659 | { |
660 | } | |
661 | ||
f4b208eb JS |
662 | /* this is called once with whichever end is closed last */ |
663 | static void pty_unix98_shutdown(struct tty_struct *tty) | |
664 | { | |
665 | devpts_kill_index(tty->driver_data, tty->index); | |
666 | } | |
667 | ||
feebed65 | 668 | static const struct tty_operations ptm_unix98_ops = { |
99f1fe18 | 669 | .lookup = ptm_unix98_lookup, |
bf970ee4 | 670 | .install = pty_unix98_install, |
7171604a | 671 | .remove = pty_unix98_remove, |
3e8e88ca AC |
672 | .open = pty_open, |
673 | .close = pty_close, | |
674 | .write = pty_write, | |
675 | .write_room = pty_write_room, | |
676 | .flush_buffer = pty_flush_buffer, | |
677 | .chars_in_buffer = pty_chars_in_buffer, | |
678 | .unthrottle = pty_unthrottle, | |
feebed65 | 679 | .ioctl = pty_unix98_ioctl, |
36b3c070 | 680 | .resize = pty_resize, |
fa2ecfc5 | 681 | .shutdown = pty_unix98_shutdown, |
36b3c070 | 682 | .cleanup = pty_cleanup |
3e8e88ca AC |
683 | }; |
684 | ||
99f1fe18 AC |
685 | static const struct tty_operations pty_unix98_ops = { |
686 | .lookup = pts_unix98_lookup, | |
bf970ee4 | 687 | .install = pty_unix98_install, |
7171604a | 688 | .remove = pty_unix98_remove, |
99f1fe18 AC |
689 | .open = pty_open, |
690 | .close = pty_close, | |
691 | .write = pty_write, | |
692 | .write_room = pty_write_room, | |
693 | .flush_buffer = pty_flush_buffer, | |
694 | .chars_in_buffer = pty_chars_in_buffer, | |
695 | .unthrottle = pty_unthrottle, | |
696 | .set_termios = pty_set_termios, | |
01adc807 PH |
697 | .start = pty_start, |
698 | .stop = pty_stop, | |
fa2ecfc5 | 699 | .shutdown = pty_unix98_shutdown, |
d03702a2 | 700 | .cleanup = pty_cleanup, |
99f1fe18 | 701 | }; |
d81ed103 AC |
702 | |
703 | /** | |
704 | * ptmx_open - open a unix 98 pty master | |
705 | * @inode: inode of device file | |
706 | * @filp: file pointer to tty | |
707 | * | |
708 | * Allocate a unix98 pty master device from the ptmx driver. | |
709 | * | |
710 | * Locking: tty_mutex protects the init_dev work. tty->count should | |
b9f8033f | 711 | * protect the rest. |
d81ed103 AC |
712 | * allocated_ptys_lock handles the list of free pty numbers |
713 | */ | |
714 | ||
64ba3dc3 | 715 | static int ptmx_open(struct inode *inode, struct file *filp) |
d81ed103 AC |
716 | { |
717 | struct tty_struct *tty; | |
162b97cf | 718 | struct inode *slave_inode; |
d81ed103 AC |
719 | int retval; |
720 | int index; | |
721 | ||
722 | nonseekable_open(inode, filp); | |
723 | ||
b0b88565 LT |
724 | /* We refuse fsnotify events on ptmx, since it's a shared resource */ |
725 | filp->f_mode |= FMODE_NONOTIFY; | |
726 | ||
fa90e1c9 JS |
727 | retval = tty_alloc_file(filp); |
728 | if (retval) | |
729 | return retval; | |
730 | ||
d81ed103 | 731 | /* find a device that is not in use. */ |
89c8d91e | 732 | mutex_lock(&devpts_mutex); |
15f1a633 | 733 | index = devpts_new_index(inode); |
fa90e1c9 JS |
734 | if (index < 0) { |
735 | retval = index; | |
05fb79e4 | 736 | mutex_unlock(&devpts_mutex); |
fa90e1c9 JS |
737 | goto err_file; |
738 | } | |
d81ed103 | 739 | |
89c8d91e AC |
740 | mutex_unlock(&devpts_mutex); |
741 | ||
d81ed103 | 742 | mutex_lock(&tty_mutex); |
593a27c4 | 743 | tty = tty_init_dev(ptm_driver, index); |
d81ed103 | 744 | |
73ec06fc AC |
745 | if (IS_ERR(tty)) { |
746 | retval = PTR_ERR(tty); | |
d81ed103 | 747 | goto out; |
73ec06fc | 748 | } |
d81ed103 | 749 | |
89c8d91e AC |
750 | /* The tty returned here is locked so we can safely |
751 | drop the mutex */ | |
752 | mutex_unlock(&tty_mutex); | |
753 | ||
d81ed103 | 754 | set_bit(TTY_PTY_LOCK, &tty->flags); /* LOCK THE SLAVE */ |
7acf6cd8 | 755 | tty->driver_data = inode; |
ee2ffa0d | 756 | |
fa90e1c9 | 757 | tty_add_file(tty, filp); |
d81ed103 | 758 | |
f11afb61 JS |
759 | slave_inode = devpts_pty_new(inode, |
760 | MKDEV(UNIX98_PTY_SLAVE_MAJOR, index), index, | |
761 | tty->link); | |
162b97cf JS |
762 | if (IS_ERR(slave_inode)) { |
763 | retval = PTR_ERR(slave_inode); | |
1177c0ef | 764 | goto err_release; |
162b97cf | 765 | } |
7acf6cd8 | 766 | tty->link->driver_data = slave_inode; |
d81ed103 AC |
767 | |
768 | retval = ptm_driver->ops->open(tty, filp); | |
64ba3dc3 | 769 | if (retval) |
1177c0ef JS |
770 | goto err_release; |
771 | ||
89c8d91e | 772 | tty_unlock(tty); |
1177c0ef JS |
773 | return 0; |
774 | err_release: | |
89c8d91e | 775 | tty_unlock(tty); |
eeb89d91 | 776 | tty_release(inode, filp); |
d81ed103 AC |
777 | return retval; |
778 | out: | |
89c8d91e | 779 | mutex_unlock(&tty_mutex); |
d3bda529 | 780 | devpts_kill_index(inode, index); |
fa90e1c9 JS |
781 | err_file: |
782 | tty_free_file(filp); | |
64ba3dc3 | 783 | return retval; |
d81ed103 AC |
784 | } |
785 | ||
786 | static struct file_operations ptmx_fops; | |
787 | ||
1da177e4 LT |
788 | static void __init unix98_pty_init(void) |
789 | { | |
21aca2fa JS |
790 | ptm_driver = tty_alloc_driver(NR_UNIX98_PTY_MAX, |
791 | TTY_DRIVER_RESET_TERMIOS | | |
792 | TTY_DRIVER_REAL_RAW | | |
793 | TTY_DRIVER_DYNAMIC_DEV | | |
794 | TTY_DRIVER_DEVPTS_MEM | | |
795 | TTY_DRIVER_DYNAMIC_ALLOC); | |
c3a6344a | 796 | if (IS_ERR(ptm_driver)) |
1da177e4 | 797 | panic("Couldn't allocate Unix98 ptm driver"); |
21aca2fa JS |
798 | pts_driver = tty_alloc_driver(NR_UNIX98_PTY_MAX, |
799 | TTY_DRIVER_RESET_TERMIOS | | |
800 | TTY_DRIVER_REAL_RAW | | |
801 | TTY_DRIVER_DYNAMIC_DEV | | |
802 | TTY_DRIVER_DEVPTS_MEM | | |
803 | TTY_DRIVER_DYNAMIC_ALLOC); | |
c3a6344a | 804 | if (IS_ERR(pts_driver)) |
1da177e4 LT |
805 | panic("Couldn't allocate Unix98 pts driver"); |
806 | ||
1da177e4 LT |
807 | ptm_driver->driver_name = "pty_master"; |
808 | ptm_driver->name = "ptm"; | |
809 | ptm_driver->major = UNIX98_PTY_MASTER_MAJOR; | |
810 | ptm_driver->minor_start = 0; | |
811 | ptm_driver->type = TTY_DRIVER_TYPE_PTY; | |
812 | ptm_driver->subtype = PTY_TYPE_MASTER; | |
813 | ptm_driver->init_termios = tty_std_termios; | |
814 | ptm_driver->init_termios.c_iflag = 0; | |
815 | ptm_driver->init_termios.c_oflag = 0; | |
816 | ptm_driver->init_termios.c_cflag = B38400 | CS8 | CREAD; | |
817 | ptm_driver->init_termios.c_lflag = 0; | |
606d099c AC |
818 | ptm_driver->init_termios.c_ispeed = 38400; |
819 | ptm_driver->init_termios.c_ospeed = 38400; | |
1da177e4 | 820 | ptm_driver->other = pts_driver; |
feebed65 | 821 | tty_set_operations(ptm_driver, &ptm_unix98_ops); |
1da177e4 | 822 | |
1da177e4 LT |
823 | pts_driver->driver_name = "pty_slave"; |
824 | pts_driver->name = "pts"; | |
825 | pts_driver->major = UNIX98_PTY_SLAVE_MAJOR; | |
826 | pts_driver->minor_start = 0; | |
827 | pts_driver->type = TTY_DRIVER_TYPE_PTY; | |
828 | pts_driver->subtype = PTY_TYPE_SLAVE; | |
829 | pts_driver->init_termios = tty_std_termios; | |
830 | pts_driver->init_termios.c_cflag = B38400 | CS8 | CREAD; | |
606d099c AC |
831 | pts_driver->init_termios.c_ispeed = 38400; |
832 | pts_driver->init_termios.c_ospeed = 38400; | |
1da177e4 | 833 | pts_driver->other = ptm_driver; |
99f1fe18 | 834 | tty_set_operations(pts_driver, &pty_unix98_ops); |
fe9cd962 | 835 | |
1da177e4 LT |
836 | if (tty_register_driver(ptm_driver)) |
837 | panic("Couldn't register Unix98 ptm driver"); | |
838 | if (tty_register_driver(pts_driver)) | |
839 | panic("Couldn't register Unix98 pts driver"); | |
840 | ||
d81ed103 AC |
841 | /* Now create the /dev/ptmx special device */ |
842 | tty_default_fops(&ptmx_fops); | |
843 | ptmx_fops.open = ptmx_open; | |
844 | ||
845 | cdev_init(&ptmx_cdev, &ptmx_fops); | |
846 | if (cdev_add(&ptmx_cdev, MKDEV(TTYAUX_MAJOR, 2), 1) || | |
847 | register_chrdev_region(MKDEV(TTYAUX_MAJOR, 2), 1, "/dev/ptmx") < 0) | |
82f8c35f | 848 | panic("Couldn't register /dev/ptmx driver"); |
d81ed103 | 849 | device_create(tty_class, NULL, MKDEV(TTYAUX_MAJOR, 2), NULL, "ptmx"); |
1da177e4 | 850 | } |
d81ed103 | 851 | |
1da177e4 LT |
852 | #else |
853 | static inline void unix98_pty_init(void) { } | |
854 | #endif | |
855 | ||
856 | static int __init pty_init(void) | |
857 | { | |
858 | legacy_pty_init(); | |
859 | unix98_pty_init(); | |
860 | return 0; | |
861 | } | |
862 | module_init(pty_init); |