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; | |
1da177e4 LT |
56 | 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); | |
ce1000dd | 61 | #ifdef CONFIG_UNIX98_PTYS |
d739e65b | 62 | if (tty->driver == ptm_driver) { |
b9f8033f | 63 | mutex_lock(&devpts_mutex); |
7acf6cd8 PH |
64 | if (tty->link->driver_data) |
65 | devpts_pty_kill(tty->link->driver_data); | |
b9f8033f | 66 | mutex_unlock(&devpts_mutex); |
d739e65b | 67 | } |
ce1000dd | 68 | #endif |
89c8d91e | 69 | tty_unlock(tty); |
11dbf203 | 70 | tty_vhangup(tty->link); |
89c8d91e | 71 | tty_lock(tty); |
1da177e4 LT |
72 | } |
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 | |
fe9cd962 | 79 | * unthrottle routine when there are fewer than TTY_THRESHOLD_UNTHROTTLE |
1da177e4 LT |
80 | * 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 | */ | |
fe9cd962 | 85 | static void pty_unthrottle(struct tty_struct *tty) |
1da177e4 | 86 | { |
d945cb9c | 87 | tty_wakeup(tty->link); |
1da177e4 LT |
88 | set_bit(TTY_THROTTLED, &tty->flags); |
89 | } | |
90 | ||
d945cb9c AC |
91 | /** |
92 | * pty_space - report space left for writing | |
93 | * @to: tty we are writing into | |
1da177e4 | 94 | * |
7bfe0b71 | 95 | * Limit the buffer space used by ptys to 8k. |
d945cb9c AC |
96 | */ |
97 | ||
98 | static int pty_space(struct tty_struct *to) | |
99 | { | |
7bfe0b71 PH |
100 | int n = tty_buffer_space_avail(to->port); |
101 | return min(n, 8192); | |
d945cb9c AC |
102 | } |
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 | |
762faaed | 109 | * |
d945cb9c AC |
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. | |
1da177e4 | 114 | */ |
d945cb9c | 115 | |
ac89a917 | 116 | static int pty_write(struct tty_struct *tty, const unsigned char *buf, int c) |
1da177e4 LT |
117 | { |
118 | struct tty_struct *to = tty->link; | |
1da177e4 | 119 | |
d945cb9c | 120 | if (tty->stopped) |
1da177e4 | 121 | return 0; |
d945cb9c | 122 | |
d945cb9c AC |
123 | if (c > 0) { |
124 | /* Stuff the data into the input queue of the other end */ | |
05c7cd39 | 125 | c = tty_insert_flip_string(to->port, buf, c); |
d945cb9c | 126 | /* And shovel */ |
5ede5253 | 127 | if (c) |
2e124b4a | 128 | tty_flip_buffer_push(to->port); |
762faaed | 129 | } |
1da177e4 LT |
130 | return c; |
131 | } | |
132 | ||
d945cb9c AC |
133 | /** |
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 | ||
1da177e4 LT |
141 | static int pty_write_room(struct tty_struct *tty) |
142 | { | |
85dfd81d LT |
143 | if (tty->stopped) |
144 | return 0; | |
d945cb9c | 145 | return pty_space(tty->link); |
1da177e4 LT |
146 | } |
147 | ||
d945cb9c AC |
148 | /** |
149 | * pty_chars_in_buffer - characters currently in our tx queue | |
150 | * @tty: our tty | |
fe9cd962 | 151 | * |
d945cb9c AC |
152 | * Report how much we have in the transmit queue. As everything is |
153 | * instantly at the other end this is easy to implement. | |
1da177e4 | 154 | */ |
d945cb9c | 155 | |
1da177e4 LT |
156 | static int pty_chars_in_buffer(struct tty_struct *tty) |
157 | { | |
d945cb9c | 158 | return 0; |
1da177e4 LT |
159 | } |
160 | ||
161 | /* Set the lock flag on a pty */ | |
fe9cd962 | 162 | static int pty_set_lock(struct tty_struct *tty, int __user *arg) |
1da177e4 LT |
163 | { |
164 | int val; | |
fe9cd962 | 165 | if (get_user(val, arg)) |
1da177e4 LT |
166 | 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 | ||
84fd7bdf CG |
174 | static 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 | ||
06026d91 CG |
180 | /* Set the packet mode on a pty */ |
181 | static int pty_set_pktmode(struct tty_struct *tty, int __user *arg) | |
182 | { | |
06026d91 CG |
183 | int pktmode; |
184 | ||
185 | if (get_user(pktmode, arg)) | |
186 | return -EFAULT; | |
187 | ||
6054c16e | 188 | spin_lock_irq(&tty->ctrl_lock); |
06026d91 CG |
189 | if (pktmode) { |
190 | if (!tty->packet) { | |
06026d91 | 191 | tty->link->ctrl_status = 0; |
2622d73e PH |
192 | smp_mb(); |
193 | tty->packet = 1; | |
06026d91 CG |
194 | } |
195 | } else | |
196 | tty->packet = 0; | |
6054c16e | 197 | spin_unlock_irq(&tty->ctrl_lock); |
06026d91 CG |
198 | |
199 | return 0; | |
200 | } | |
201 | ||
84fd7bdf CG |
202 | /* Get the packet mode of a pty */ |
203 | static 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 | ||
26df6d13 | 209 | /* Send a signal to the slave */ |
210 | static int pty_signal(struct tty_struct *tty, int sig) | |
211 | { | |
26df6d13 | 212 | struct pid *pgrp; |
213 | ||
214 | if (tty->link) { | |
5b239542 PH |
215 | pgrp = tty_get_pgrp(tty->link); |
216 | if (pgrp) | |
217 | kill_pgrp(pgrp, sig, 1); | |
26df6d13 | 218 | put_pid(pgrp); |
219 | } | |
220 | return 0; | |
221 | } | |
222 | ||
1da177e4 LT |
223 | static void pty_flush_buffer(struct tty_struct *tty) |
224 | { | |
225 | struct tty_struct *to = tty->link; | |
fe9cd962 | 226 | |
1da177e4 LT |
227 | if (!to) |
228 | return; | |
d945cb9c | 229 | /* tty_buffer_flush(to); FIXME */ |
1da177e4 | 230 | if (to->packet) { |
6054c16e | 231 | spin_lock_irq(&tty->ctrl_lock); |
1da177e4 LT |
232 | tty->ctrl_status |= TIOCPKT_FLUSHWRITE; |
233 | wake_up_interruptible(&to->read_wait); | |
6054c16e | 234 | spin_unlock_irq(&tty->ctrl_lock); |
1da177e4 LT |
235 | } |
236 | } | |
237 | ||
fe9cd962 | 238 | static int pty_open(struct tty_struct *tty, struct file *filp) |
1da177e4 | 239 | { |
1da177e4 | 240 | if (!tty || !tty->link) |
7c61c3d8 | 241 | return -ENODEV; |
69939035 | 242 | |
1da177e4 LT |
243 | if (test_bit(TTY_OTHER_CLOSED, &tty->flags)) |
244 | goto out; | |
245 | if (test_bit(TTY_PTY_LOCK, &tty->link->flags)) | |
246 | goto out; | |
80cace72 | 247 | if (tty->driver->subtype == PTY_TYPE_SLAVE && tty->link->count != 1) |
1da177e4 LT |
248 | goto out; |
249 | ||
69939035 | 250 | clear_bit(TTY_IO_ERROR, &tty->flags); |
1da177e4 LT |
251 | clear_bit(TTY_OTHER_CLOSED, &tty->link->flags); |
252 | set_bit(TTY_THROTTLED, &tty->flags); | |
7c61c3d8 PH |
253 | return 0; |
254 | ||
1da177e4 | 255 | out: |
7c61c3d8 PH |
256 | set_bit(TTY_IO_ERROR, &tty->flags); |
257 | return -EIO; | |
1da177e4 LT |
258 | } |
259 | ||
fe9cd962 AC |
260 | static void pty_set_termios(struct tty_struct *tty, |
261 | struct ktermios *old_termios) | |
1da177e4 | 262 | { |
dbfcd851 PH |
263 | /* 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) { | |
4d8c1dff | 274 | spin_lock_irq(&tty->ctrl_lock); |
dbfcd851 PH |
275 | 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; | |
4d8c1dff | 284 | spin_unlock_irq(&tty->ctrl_lock); |
dbfcd851 PH |
285 | wake_up_interruptible(&tty->link->read_wait); |
286 | } | |
287 | } | |
288 | ||
adc8d746 AC |
289 | tty->termios.c_cflag &= ~(CSIZE | PARENB); |
290 | tty->termios.c_cflag |= (CS8 | CREAD); | |
1da177e4 LT |
291 | } |
292 | ||
fc6f6238 AC |
293 | /** |
294 | * pty_do_resize - resize event | |
295 | * @tty: tty being resized | |
c774bda2 | 296 | * @ws: window size being set. |
fc6f6238 | 297 | * |
3ad2f3fb | 298 | * Update the termios variables and send the necessary signals to |
fc6f6238 AC |
299 | * peform a terminal resize correctly |
300 | */ | |
301 | ||
159a8e92 | 302 | static int pty_resize(struct tty_struct *tty, struct winsize *ws) |
fc6f6238 AC |
303 | { |
304 | struct pid *pgrp, *rpgrp; | |
fc6f6238 AC |
305 | struct tty_struct *pty = tty->link; |
306 | ||
307 | /* For a PTY we need to lock the tty side */ | |
dee4a0be | 308 | mutex_lock(&tty->winsize_mutex); |
fc6f6238 AC |
309 | if (!memcmp(ws, &tty->winsize, sizeof(*ws))) |
310 | goto done; | |
311 | ||
5b239542 PH |
312 | /* Signal the foreground process group of both ptys */ |
313 | pgrp = tty_get_pgrp(tty); | |
314 | rpgrp = tty_get_pgrp(pty); | |
fc6f6238 AC |
315 | |
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 */ | |
326 | done: | |
dee4a0be | 327 | mutex_unlock(&tty->winsize_mutex); |
fc6f6238 AC |
328 | return 0; |
329 | } | |
330 | ||
01adc807 PH |
331 | /** |
332 | * 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 | */ | |
341 | static void pty_start(struct tty_struct *tty) | |
342 | { | |
343 | unsigned long flags; | |
344 | ||
01adc807 | 345 | if (tty->link && tty->link->packet) { |
54e8e5fc | 346 | spin_lock_irqsave(&tty->ctrl_lock, flags); |
01adc807 PH |
347 | tty->ctrl_status &= ~TIOCPKT_STOP; |
348 | tty->ctrl_status |= TIOCPKT_START; | |
54e8e5fc | 349 | spin_unlock_irqrestore(&tty->ctrl_lock, flags); |
01adc807 PH |
350 | wake_up_interruptible_poll(&tty->link->read_wait, POLLIN); |
351 | } | |
01adc807 PH |
352 | } |
353 | ||
354 | static void pty_stop(struct tty_struct *tty) | |
355 | { | |
356 | unsigned long flags; | |
357 | ||
01adc807 | 358 | if (tty->link && tty->link->packet) { |
54e8e5fc | 359 | spin_lock_irqsave(&tty->ctrl_lock, flags); |
01adc807 PH |
360 | tty->ctrl_status &= ~TIOCPKT_START; |
361 | tty->ctrl_status |= TIOCPKT_STOP; | |
54e8e5fc | 362 | spin_unlock_irqrestore(&tty->ctrl_lock, flags); |
01adc807 PH |
363 | wake_up_interruptible_poll(&tty->link->read_wait, POLLIN); |
364 | } | |
01adc807 PH |
365 | } |
366 | ||
d155255a AC |
367 | /** |
368 | * pty_common_install - set up the pty pair | |
369 | * @driver: the pty driver | |
370 | * @tty: the tty being instantiated | |
2c964a2f | 371 | * @legacy: true if this is BSD style |
d155255a AC |
372 | * |
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 | */ | |
5d249bc6 JS |
378 | static int pty_common_install(struct tty_driver *driver, struct tty_struct *tty, |
379 | bool legacy) | |
bf970ee4 AC |
380 | { |
381 | struct tty_struct *o_tty; | |
d03702a2 | 382 | struct tty_port *ports[2]; |
bf970ee4 | 383 | int idx = tty->index; |
5d249bc6 | 384 | int retval = -ENOMEM; |
bf970ee4 | 385 | |
d03702a2 JS |
386 | ports[0] = kmalloc(sizeof **ports, GFP_KERNEL); |
387 | ports[1] = kmalloc(sizeof **ports, GFP_KERNEL); | |
6f9ea7ad | 388 | if (!ports[0] || !ports[1]) |
2c964a2f | 389 | goto err; |
bf970ee4 AC |
390 | if (!try_module_get(driver->other->owner)) { |
391 | /* This cannot in fact currently happen */ | |
2c964a2f | 392 | goto err; |
bf970ee4 | 393 | } |
2c964a2f RV |
394 | o_tty = alloc_tty_struct(driver->other, idx); |
395 | if (!o_tty) | |
396 | goto err_put_module; | |
bf970ee4 | 397 | |
5d249bc6 JS |
398 | if (legacy) { |
399 | /* We always use new tty termios data so we can do this | |
400 | the easy way .. */ | |
401 | retval = tty_init_termios(tty); | |
402 | if (retval) | |
403 | goto err_deinit_tty; | |
404 | ||
405 | retval = tty_init_termios(o_tty); | |
406 | if (retval) | |
407 | goto err_free_termios; | |
408 | ||
409 | driver->other->ttys[idx] = o_tty; | |
410 | driver->ttys[idx] = tty; | |
411 | } else { | |
adc8d746 AC |
412 | memset(&tty->termios_locked, 0, sizeof(tty->termios_locked)); |
413 | tty->termios = driver->init_termios; | |
414 | memset(&o_tty->termios_locked, 0, sizeof(tty->termios_locked)); | |
415 | o_tty->termios = driver->other->init_termios; | |
5d249bc6 | 416 | } |
fe9cd962 | 417 | |
bf970ee4 AC |
418 | /* |
419 | * Everything allocated ... set up the o_tty structure. | |
420 | */ | |
bf970ee4 AC |
421 | tty_driver_kref_get(driver->other); |
422 | if (driver->subtype == PTY_TYPE_MASTER) | |
423 | o_tty->count++; | |
424 | /* Establish the links in both directions */ | |
425 | tty->link = o_tty; | |
426 | o_tty->link = tty; | |
d03702a2 JS |
427 | tty_port_init(ports[0]); |
428 | tty_port_init(ports[1]); | |
429 | o_tty->port = ports[0]; | |
430 | tty->port = ports[1]; | |
967fab69 | 431 | o_tty->port->itty = o_tty; |
bf970ee4 AC |
432 | |
433 | tty_driver_kref_get(driver); | |
434 | tty->count++; | |
bf970ee4 | 435 | return 0; |
8a1b8d70 | 436 | err_free_termios: |
5d249bc6 JS |
437 | if (legacy) |
438 | tty_free_termios(tty); | |
a9dccddb JS |
439 | err_deinit_tty: |
440 | deinitialize_tty_struct(o_tty); | |
2c964a2f RV |
441 | free_tty_struct(o_tty); |
442 | err_put_module: | |
07584d4a | 443 | module_put(driver->other->owner); |
2c964a2f | 444 | err: |
d03702a2 JS |
445 | kfree(ports[0]); |
446 | kfree(ports[1]); | |
8a1b8d70 | 447 | return retval; |
bf970ee4 AC |
448 | } |
449 | ||
d03702a2 JS |
450 | static void pty_cleanup(struct tty_struct *tty) |
451 | { | |
81c79838 | 452 | tty_port_put(tty->port); |
d03702a2 JS |
453 | } |
454 | ||
5d249bc6 JS |
455 | /* Traditional BSD devices */ |
456 | #ifdef CONFIG_LEGACY_PTYS | |
457 | ||
458 | static int pty_install(struct tty_driver *driver, struct tty_struct *tty) | |
459 | { | |
460 | return pty_common_install(driver, tty, true); | |
461 | } | |
462 | ||
d155255a AC |
463 | static void pty_remove(struct tty_driver *driver, struct tty_struct *tty) |
464 | { | |
465 | struct tty_struct *pair = tty->link; | |
466 | driver->ttys[tty->index] = NULL; | |
467 | if (pair) | |
468 | pair->driver->ttys[pair->index] = NULL; | |
469 | } | |
470 | ||
6caa76b7 | 471 | static int pty_bsd_ioctl(struct tty_struct *tty, |
1da177e4 LT |
472 | unsigned int cmd, unsigned long arg) |
473 | { | |
474 | switch (cmd) { | |
475 | case TIOCSPTLCK: /* Set PT Lock (disallow slave open) */ | |
476 | return pty_set_lock(tty, (int __user *) arg); | |
84fd7bdf CG |
477 | case TIOCGPTLCK: /* Get PT Lock status */ |
478 | return pty_get_lock(tty, (int __user *)arg); | |
06026d91 CG |
479 | case TIOCPKT: /* Set PT packet mode */ |
480 | return pty_set_pktmode(tty, (int __user *)arg); | |
84fd7bdf CG |
481 | case TIOCGPKT: /* Get PT packet mode */ |
482 | return pty_get_pktmode(tty, (int __user *)arg); | |
26df6d13 | 483 | case TIOCSIG: /* Send signal to other side of pty */ |
484 | return pty_signal(tty, (int) arg); | |
ded2f295 JS |
485 | case TIOCGPTN: /* TTY returns ENOTTY, but glibc expects EINVAL here */ |
486 | return -EINVAL; | |
1da177e4 LT |
487 | } |
488 | return -ENOIOCTLCMD; | |
489 | } | |
490 | ||
dc8c8587 KS |
491 | static int legacy_count = CONFIG_LEGACY_PTY_COUNT; |
492 | module_param(legacy_count, int, 0); | |
493 | ||
342a5971 LT |
494 | /* |
495 | * The master side of a pty can do TIOCSPTLCK and thus | |
496 | * has pty_bsd_ioctl. | |
497 | */ | |
498 | static const struct tty_operations master_pty_ops_bsd = { | |
499 | .install = pty_install, | |
3e8e88ca AC |
500 | .open = pty_open, |
501 | .close = pty_close, | |
502 | .write = pty_write, | |
503 | .write_room = pty_write_room, | |
504 | .flush_buffer = pty_flush_buffer, | |
505 | .chars_in_buffer = pty_chars_in_buffer, | |
506 | .unthrottle = pty_unthrottle, | |
3e8e88ca | 507 | .ioctl = pty_bsd_ioctl, |
d03702a2 | 508 | .cleanup = pty_cleanup, |
d155255a AC |
509 | .resize = pty_resize, |
510 | .remove = pty_remove | |
3e8e88ca AC |
511 | }; |
512 | ||
342a5971 LT |
513 | static const struct tty_operations slave_pty_ops_bsd = { |
514 | .install = pty_install, | |
515 | .open = pty_open, | |
516 | .close = pty_close, | |
517 | .write = pty_write, | |
518 | .write_room = pty_write_room, | |
519 | .flush_buffer = pty_flush_buffer, | |
520 | .chars_in_buffer = pty_chars_in_buffer, | |
521 | .unthrottle = pty_unthrottle, | |
522 | .set_termios = pty_set_termios, | |
d03702a2 | 523 | .cleanup = pty_cleanup, |
d155255a | 524 | .resize = pty_resize, |
01adc807 PH |
525 | .start = pty_start, |
526 | .stop = pty_stop, | |
d155255a | 527 | .remove = pty_remove |
342a5971 LT |
528 | }; |
529 | ||
1da177e4 LT |
530 | static void __init legacy_pty_init(void) |
531 | { | |
342a5971 LT |
532 | struct tty_driver *pty_driver, *pty_slave_driver; |
533 | ||
dc8c8587 KS |
534 | if (legacy_count <= 0) |
535 | return; | |
1da177e4 | 536 | |
21aca2fa JS |
537 | pty_driver = tty_alloc_driver(legacy_count, |
538 | TTY_DRIVER_RESET_TERMIOS | | |
539 | TTY_DRIVER_REAL_RAW | | |
540 | TTY_DRIVER_DYNAMIC_ALLOC); | |
c3a6344a | 541 | if (IS_ERR(pty_driver)) |
1da177e4 LT |
542 | panic("Couldn't allocate pty driver"); |
543 | ||
21aca2fa JS |
544 | pty_slave_driver = tty_alloc_driver(legacy_count, |
545 | TTY_DRIVER_RESET_TERMIOS | | |
546 | TTY_DRIVER_REAL_RAW | | |
547 | TTY_DRIVER_DYNAMIC_ALLOC); | |
c3a6344a | 548 | if (IS_ERR(pty_slave_driver)) |
1da177e4 LT |
549 | panic("Couldn't allocate pty slave driver"); |
550 | ||
1da177e4 LT |
551 | pty_driver->driver_name = "pty_master"; |
552 | pty_driver->name = "pty"; | |
1da177e4 LT |
553 | pty_driver->major = PTY_MASTER_MAJOR; |
554 | pty_driver->minor_start = 0; | |
555 | pty_driver->type = TTY_DRIVER_TYPE_PTY; | |
556 | pty_driver->subtype = PTY_TYPE_MASTER; | |
557 | pty_driver->init_termios = tty_std_termios; | |
558 | pty_driver->init_termios.c_iflag = 0; | |
559 | pty_driver->init_termios.c_oflag = 0; | |
560 | pty_driver->init_termios.c_cflag = B38400 | CS8 | CREAD; | |
561 | pty_driver->init_termios.c_lflag = 0; | |
606d099c AC |
562 | pty_driver->init_termios.c_ispeed = 38400; |
563 | pty_driver->init_termios.c_ospeed = 38400; | |
1da177e4 | 564 | pty_driver->other = pty_slave_driver; |
342a5971 | 565 | tty_set_operations(pty_driver, &master_pty_ops_bsd); |
1da177e4 | 566 | |
1da177e4 LT |
567 | pty_slave_driver->driver_name = "pty_slave"; |
568 | pty_slave_driver->name = "ttyp"; | |
1da177e4 LT |
569 | pty_slave_driver->major = PTY_SLAVE_MAJOR; |
570 | pty_slave_driver->minor_start = 0; | |
571 | pty_slave_driver->type = TTY_DRIVER_TYPE_PTY; | |
572 | pty_slave_driver->subtype = PTY_TYPE_SLAVE; | |
573 | pty_slave_driver->init_termios = tty_std_termios; | |
574 | pty_slave_driver->init_termios.c_cflag = B38400 | CS8 | CREAD; | |
606d099c AC |
575 | pty_slave_driver->init_termios.c_ispeed = 38400; |
576 | pty_slave_driver->init_termios.c_ospeed = 38400; | |
1da177e4 | 577 | pty_slave_driver->other = pty_driver; |
342a5971 | 578 | tty_set_operations(pty_slave_driver, &slave_pty_ops_bsd); |
1da177e4 LT |
579 | |
580 | if (tty_register_driver(pty_driver)) | |
581 | panic("Couldn't register pty driver"); | |
582 | if (tty_register_driver(pty_slave_driver)) | |
583 | panic("Couldn't register pty slave driver"); | |
584 | } | |
585 | #else | |
586 | static inline void legacy_pty_init(void) { } | |
587 | #endif | |
588 | ||
589 | /* Unix98 devices */ | |
590 | #ifdef CONFIG_UNIX98_PTYS | |
1da177e4 | 591 | |
d81ed103 AC |
592 | static struct cdev ptmx_cdev; |
593 | ||
6caa76b7 | 594 | static int pty_unix98_ioctl(struct tty_struct *tty, |
1da177e4 LT |
595 | unsigned int cmd, unsigned long arg) |
596 | { | |
597 | switch (cmd) { | |
598 | case TIOCSPTLCK: /* Set PT Lock (disallow slave open) */ | |
599 | return pty_set_lock(tty, (int __user *)arg); | |
84fd7bdf CG |
600 | case TIOCGPTLCK: /* Get PT Lock status */ |
601 | return pty_get_lock(tty, (int __user *)arg); | |
06026d91 CG |
602 | case TIOCPKT: /* Set PT packet mode */ |
603 | return pty_set_pktmode(tty, (int __user *)arg); | |
84fd7bdf CG |
604 | case TIOCGPKT: /* Get PT packet mode */ |
605 | return pty_get_pktmode(tty, (int __user *)arg); | |
1da177e4 LT |
606 | case TIOCGPTN: /* Get PT Number */ |
607 | return put_user(tty->index, (unsigned int __user *)arg); | |
26df6d13 | 608 | case TIOCSIG: /* Send signal to other side of pty */ |
609 | return pty_signal(tty, (int) arg); | |
1da177e4 LT |
610 | } |
611 | ||
612 | return -ENOIOCTLCMD; | |
613 | } | |
614 | ||
99f1fe18 AC |
615 | /** |
616 | * ptm_unix98_lookup - find a pty master | |
617 | * @driver: ptm driver | |
618 | * @idx: tty index | |
619 | * | |
620 | * Look up a pty master device. Called under the tty_mutex for now. | |
621 | * This provides our locking. | |
622 | */ | |
623 | ||
15f1a633 SB |
624 | static struct tty_struct *ptm_unix98_lookup(struct tty_driver *driver, |
625 | struct inode *ptm_inode, int idx) | |
99f1fe18 | 626 | { |
593a27c4 KK |
627 | /* Master must be open via /dev/ptmx */ |
628 | return ERR_PTR(-EIO); | |
99f1fe18 AC |
629 | } |
630 | ||
631 | /** | |
632 | * pts_unix98_lookup - find a pty slave | |
633 | * @driver: pts driver | |
634 | * @idx: tty index | |
635 | * | |
636 | * Look up a pty master device. Called under the tty_mutex for now. | |
d739e65b | 637 | * This provides our locking for the tty pointer. |
99f1fe18 AC |
638 | */ |
639 | ||
15f1a633 SB |
640 | static struct tty_struct *pts_unix98_lookup(struct tty_driver *driver, |
641 | struct inode *pts_inode, int idx) | |
99f1fe18 | 642 | { |
d739e65b AC |
643 | struct tty_struct *tty; |
644 | ||
645 | mutex_lock(&devpts_mutex); | |
8fcbaa2b | 646 | tty = devpts_get_priv(pts_inode); |
d739e65b | 647 | mutex_unlock(&devpts_mutex); |
99f1fe18 AC |
648 | /* Master must be open before slave */ |
649 | if (!tty) | |
650 | return ERR_PTR(-EIO); | |
651 | return tty; | |
652 | } | |
653 | ||
8b0a88d5 AC |
654 | /* We have no need to install and remove our tty objects as devpts does all |
655 | the work for us */ | |
656 | ||
bf970ee4 | 657 | static int pty_unix98_install(struct tty_driver *driver, struct tty_struct *tty) |
8b0a88d5 | 658 | { |
5d249bc6 | 659 | return pty_common_install(driver, tty, false); |
8b0a88d5 AC |
660 | } |
661 | ||
7171604a | 662 | static void pty_unix98_remove(struct tty_driver *driver, struct tty_struct *tty) |
8b0a88d5 AC |
663 | { |
664 | } | |
665 | ||
f4b208eb JS |
666 | /* this is called once with whichever end is closed last */ |
667 | static void pty_unix98_shutdown(struct tty_struct *tty) | |
668 | { | |
669 | devpts_kill_index(tty->driver_data, tty->index); | |
670 | } | |
671 | ||
feebed65 | 672 | static const struct tty_operations ptm_unix98_ops = { |
99f1fe18 | 673 | .lookup = ptm_unix98_lookup, |
bf970ee4 | 674 | .install = pty_unix98_install, |
7171604a | 675 | .remove = pty_unix98_remove, |
3e8e88ca AC |
676 | .open = pty_open, |
677 | .close = pty_close, | |
678 | .write = pty_write, | |
679 | .write_room = pty_write_room, | |
680 | .flush_buffer = pty_flush_buffer, | |
681 | .chars_in_buffer = pty_chars_in_buffer, | |
682 | .unthrottle = pty_unthrottle, | |
feebed65 | 683 | .ioctl = pty_unix98_ioctl, |
36b3c070 | 684 | .resize = pty_resize, |
fa2ecfc5 | 685 | .shutdown = pty_unix98_shutdown, |
36b3c070 | 686 | .cleanup = pty_cleanup |
3e8e88ca AC |
687 | }; |
688 | ||
99f1fe18 AC |
689 | static const struct tty_operations pty_unix98_ops = { |
690 | .lookup = pts_unix98_lookup, | |
bf970ee4 | 691 | .install = pty_unix98_install, |
7171604a | 692 | .remove = pty_unix98_remove, |
99f1fe18 AC |
693 | .open = pty_open, |
694 | .close = pty_close, | |
695 | .write = pty_write, | |
696 | .write_room = pty_write_room, | |
697 | .flush_buffer = pty_flush_buffer, | |
698 | .chars_in_buffer = pty_chars_in_buffer, | |
699 | .unthrottle = pty_unthrottle, | |
700 | .set_termios = pty_set_termios, | |
01adc807 PH |
701 | .start = pty_start, |
702 | .stop = pty_stop, | |
fa2ecfc5 | 703 | .shutdown = pty_unix98_shutdown, |
d03702a2 | 704 | .cleanup = pty_cleanup, |
99f1fe18 | 705 | }; |
d81ed103 AC |
706 | |
707 | /** | |
708 | * ptmx_open - open a unix 98 pty master | |
709 | * @inode: inode of device file | |
710 | * @filp: file pointer to tty | |
711 | * | |
712 | * Allocate a unix98 pty master device from the ptmx driver. | |
713 | * | |
714 | * Locking: tty_mutex protects the init_dev work. tty->count should | |
b9f8033f | 715 | * protect the rest. |
d81ed103 AC |
716 | * allocated_ptys_lock handles the list of free pty numbers |
717 | */ | |
718 | ||
64ba3dc3 | 719 | static int ptmx_open(struct inode *inode, struct file *filp) |
d81ed103 AC |
720 | { |
721 | struct tty_struct *tty; | |
162b97cf | 722 | struct inode *slave_inode; |
d81ed103 AC |
723 | int retval; |
724 | int index; | |
725 | ||
726 | nonseekable_open(inode, filp); | |
727 | ||
b0b88565 LT |
728 | /* We refuse fsnotify events on ptmx, since it's a shared resource */ |
729 | filp->f_mode |= FMODE_NONOTIFY; | |
730 | ||
fa90e1c9 JS |
731 | retval = tty_alloc_file(filp); |
732 | if (retval) | |
733 | return retval; | |
734 | ||
d81ed103 | 735 | /* find a device that is not in use. */ |
89c8d91e | 736 | mutex_lock(&devpts_mutex); |
15f1a633 | 737 | index = devpts_new_index(inode); |
fa90e1c9 JS |
738 | if (index < 0) { |
739 | retval = index; | |
05fb79e4 | 740 | mutex_unlock(&devpts_mutex); |
fa90e1c9 JS |
741 | goto err_file; |
742 | } | |
d81ed103 | 743 | |
89c8d91e AC |
744 | mutex_unlock(&devpts_mutex); |
745 | ||
d81ed103 | 746 | mutex_lock(&tty_mutex); |
593a27c4 | 747 | tty = tty_init_dev(ptm_driver, index); |
d81ed103 | 748 | |
73ec06fc AC |
749 | if (IS_ERR(tty)) { |
750 | retval = PTR_ERR(tty); | |
d81ed103 | 751 | goto out; |
73ec06fc | 752 | } |
d81ed103 | 753 | |
89c8d91e AC |
754 | /* The tty returned here is locked so we can safely |
755 | drop the mutex */ | |
756 | mutex_unlock(&tty_mutex); | |
757 | ||
d81ed103 | 758 | set_bit(TTY_PTY_LOCK, &tty->flags); /* LOCK THE SLAVE */ |
7acf6cd8 | 759 | tty->driver_data = inode; |
ee2ffa0d | 760 | |
fa90e1c9 | 761 | tty_add_file(tty, filp); |
d81ed103 | 762 | |
f11afb61 JS |
763 | slave_inode = devpts_pty_new(inode, |
764 | MKDEV(UNIX98_PTY_SLAVE_MAJOR, index), index, | |
765 | tty->link); | |
162b97cf JS |
766 | if (IS_ERR(slave_inode)) { |
767 | retval = PTR_ERR(slave_inode); | |
1177c0ef | 768 | goto err_release; |
162b97cf | 769 | } |
7acf6cd8 | 770 | tty->link->driver_data = slave_inode; |
d81ed103 AC |
771 | |
772 | retval = ptm_driver->ops->open(tty, filp); | |
64ba3dc3 | 773 | if (retval) |
1177c0ef JS |
774 | goto err_release; |
775 | ||
89c8d91e | 776 | tty_unlock(tty); |
1177c0ef JS |
777 | return 0; |
778 | err_release: | |
89c8d91e | 779 | tty_unlock(tty); |
eeb89d91 | 780 | tty_release(inode, filp); |
d81ed103 AC |
781 | return retval; |
782 | out: | |
89c8d91e | 783 | mutex_unlock(&tty_mutex); |
d3bda529 | 784 | devpts_kill_index(inode, index); |
fa90e1c9 JS |
785 | err_file: |
786 | tty_free_file(filp); | |
64ba3dc3 | 787 | return retval; |
d81ed103 AC |
788 | } |
789 | ||
790 | static struct file_operations ptmx_fops; | |
791 | ||
1da177e4 LT |
792 | static void __init unix98_pty_init(void) |
793 | { | |
21aca2fa JS |
794 | ptm_driver = tty_alloc_driver(NR_UNIX98_PTY_MAX, |
795 | TTY_DRIVER_RESET_TERMIOS | | |
796 | TTY_DRIVER_REAL_RAW | | |
797 | TTY_DRIVER_DYNAMIC_DEV | | |
798 | TTY_DRIVER_DEVPTS_MEM | | |
799 | TTY_DRIVER_DYNAMIC_ALLOC); | |
c3a6344a | 800 | if (IS_ERR(ptm_driver)) |
1da177e4 | 801 | panic("Couldn't allocate Unix98 ptm driver"); |
21aca2fa JS |
802 | pts_driver = tty_alloc_driver(NR_UNIX98_PTY_MAX, |
803 | TTY_DRIVER_RESET_TERMIOS | | |
804 | TTY_DRIVER_REAL_RAW | | |
805 | TTY_DRIVER_DYNAMIC_DEV | | |
806 | TTY_DRIVER_DEVPTS_MEM | | |
807 | TTY_DRIVER_DYNAMIC_ALLOC); | |
c3a6344a | 808 | if (IS_ERR(pts_driver)) |
1da177e4 LT |
809 | panic("Couldn't allocate Unix98 pts driver"); |
810 | ||
1da177e4 LT |
811 | ptm_driver->driver_name = "pty_master"; |
812 | ptm_driver->name = "ptm"; | |
813 | ptm_driver->major = UNIX98_PTY_MASTER_MAJOR; | |
814 | ptm_driver->minor_start = 0; | |
815 | ptm_driver->type = TTY_DRIVER_TYPE_PTY; | |
816 | ptm_driver->subtype = PTY_TYPE_MASTER; | |
817 | ptm_driver->init_termios = tty_std_termios; | |
818 | ptm_driver->init_termios.c_iflag = 0; | |
819 | ptm_driver->init_termios.c_oflag = 0; | |
820 | ptm_driver->init_termios.c_cflag = B38400 | CS8 | CREAD; | |
821 | ptm_driver->init_termios.c_lflag = 0; | |
606d099c AC |
822 | ptm_driver->init_termios.c_ispeed = 38400; |
823 | ptm_driver->init_termios.c_ospeed = 38400; | |
1da177e4 | 824 | ptm_driver->other = pts_driver; |
feebed65 | 825 | tty_set_operations(ptm_driver, &ptm_unix98_ops); |
1da177e4 | 826 | |
1da177e4 LT |
827 | pts_driver->driver_name = "pty_slave"; |
828 | pts_driver->name = "pts"; | |
829 | pts_driver->major = UNIX98_PTY_SLAVE_MAJOR; | |
830 | pts_driver->minor_start = 0; | |
831 | pts_driver->type = TTY_DRIVER_TYPE_PTY; | |
832 | pts_driver->subtype = PTY_TYPE_SLAVE; | |
833 | pts_driver->init_termios = tty_std_termios; | |
834 | pts_driver->init_termios.c_cflag = B38400 | CS8 | CREAD; | |
606d099c AC |
835 | pts_driver->init_termios.c_ispeed = 38400; |
836 | pts_driver->init_termios.c_ospeed = 38400; | |
1da177e4 | 837 | pts_driver->other = ptm_driver; |
99f1fe18 | 838 | tty_set_operations(pts_driver, &pty_unix98_ops); |
fe9cd962 | 839 | |
1da177e4 LT |
840 | if (tty_register_driver(ptm_driver)) |
841 | panic("Couldn't register Unix98 ptm driver"); | |
842 | if (tty_register_driver(pts_driver)) | |
843 | panic("Couldn't register Unix98 pts driver"); | |
844 | ||
d81ed103 AC |
845 | /* Now create the /dev/ptmx special device */ |
846 | tty_default_fops(&ptmx_fops); | |
847 | ptmx_fops.open = ptmx_open; | |
848 | ||
849 | cdev_init(&ptmx_cdev, &ptmx_fops); | |
850 | if (cdev_add(&ptmx_cdev, MKDEV(TTYAUX_MAJOR, 2), 1) || | |
851 | register_chrdev_region(MKDEV(TTYAUX_MAJOR, 2), 1, "/dev/ptmx") < 0) | |
82f8c35f | 852 | panic("Couldn't register /dev/ptmx driver"); |
d81ed103 | 853 | device_create(tty_class, NULL, MKDEV(TTYAUX_MAJOR, 2), NULL, "ptmx"); |
1da177e4 | 854 | } |
d81ed103 | 855 | |
1da177e4 LT |
856 | #else |
857 | static inline void unix98_pty_init(void) { } | |
858 | #endif | |
859 | ||
860 | static int __init pty_init(void) | |
861 | { | |
862 | legacy_pty_init(); | |
863 | unix98_pty_init(); | |
864 | return 0; | |
865 | } | |
866 | module_init(pty_init); |