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> |
1da177e4 | 27 | |
fe9cd962 | 28 | |
1da177e4 | 29 | #ifdef CONFIG_UNIX98_PTYS |
da2bdf9a | 30 | static struct tty_driver *ptm_driver; |
1da177e4 | 31 | static struct tty_driver *pts_driver; |
d739e65b | 32 | static DEFINE_MUTEX(devpts_mutex); |
1da177e4 LT |
33 | #endif |
34 | ||
fe9cd962 | 35 | static void pty_close(struct tty_struct *tty, struct file *filp) |
1da177e4 | 36 | { |
fe9cd962 AC |
37 | BUG_ON(!tty); |
38 | if (tty->driver->subtype == PTY_TYPE_MASTER) | |
39 | WARN_ON(tty->count > 1); | |
40 | else { | |
1da177e4 LT |
41 | if (tty->count > 2) |
42 | return; | |
43 | } | |
44 | wake_up_interruptible(&tty->read_wait); | |
45 | wake_up_interruptible(&tty->write_wait); | |
46 | tty->packet = 0; | |
89c8d91e | 47 | /* Review - krefs on tty_link ?? */ |
1da177e4 LT |
48 | if (!tty->link) |
49 | return; | |
50 | tty->link->packet = 0; | |
51 | set_bit(TTY_OTHER_CLOSED, &tty->link->flags); | |
52 | wake_up_interruptible(&tty->link->read_wait); | |
53 | wake_up_interruptible(&tty->link->write_wait); | |
54 | if (tty->driver->subtype == PTY_TYPE_MASTER) { | |
55 | set_bit(TTY_OTHER_CLOSED, &tty->flags); | |
ce1000dd | 56 | #ifdef CONFIG_UNIX98_PTYS |
d739e65b AC |
57 | if (tty->driver == ptm_driver) { |
58 | mutex_lock(&devpts_mutex); | |
f11afb61 | 59 | devpts_pty_kill(tty->link->driver_data); |
d739e65b AC |
60 | mutex_unlock(&devpts_mutex); |
61 | } | |
ce1000dd | 62 | #endif |
89c8d91e | 63 | tty_unlock(tty); |
11dbf203 | 64 | tty_vhangup(tty->link); |
89c8d91e | 65 | tty_lock(tty); |
1da177e4 LT |
66 | } |
67 | } | |
68 | ||
69 | /* | |
70 | * The unthrottle routine is called by the line discipline to signal | |
71 | * that it can receive more characters. For PTY's, the TTY_THROTTLED | |
72 | * flag is always set, to force the line discipline to always call the | |
fe9cd962 | 73 | * unthrottle routine when there are fewer than TTY_THRESHOLD_UNTHROTTLE |
1da177e4 LT |
74 | * characters in the queue. This is necessary since each time this |
75 | * happens, we need to wake up any sleeping processes that could be | |
76 | * (1) trying to send data to the pty, or (2) waiting in wait_until_sent() | |
77 | * for the pty buffer to be drained. | |
78 | */ | |
fe9cd962 | 79 | static void pty_unthrottle(struct tty_struct *tty) |
1da177e4 | 80 | { |
d945cb9c | 81 | tty_wakeup(tty->link); |
1da177e4 LT |
82 | set_bit(TTY_THROTTLED, &tty->flags); |
83 | } | |
84 | ||
d945cb9c AC |
85 | /** |
86 | * pty_space - report space left for writing | |
87 | * @to: tty we are writing into | |
1da177e4 | 88 | * |
d945cb9c AC |
89 | * The tty buffers allow 64K but we sneak a peak and clip at 8K this |
90 | * allows a lot of overspill room for echo and other fun messes to | |
91 | * be handled properly | |
92 | */ | |
93 | ||
94 | static int pty_space(struct tty_struct *to) | |
95 | { | |
96 | int n = 8192 - to->buf.memory_used; | |
97 | if (n < 0) | |
98 | return 0; | |
99 | return n; | |
100 | } | |
101 | ||
102 | /** | |
103 | * pty_write - write to a pty | |
104 | * @tty: the tty we write from | |
105 | * @buf: kernel buffer of data | |
106 | * @count: bytes to write | |
762faaed | 107 | * |
d945cb9c AC |
108 | * Our "hardware" write method. Data is coming from the ldisc which |
109 | * may be in a non sleeping state. We simply throw this at the other | |
110 | * end of the link as if we were an IRQ handler receiving stuff for | |
111 | * the other side of the pty/tty pair. | |
1da177e4 | 112 | */ |
d945cb9c | 113 | |
ac89a917 | 114 | static int pty_write(struct tty_struct *tty, const unsigned char *buf, int c) |
1da177e4 LT |
115 | { |
116 | struct tty_struct *to = tty->link; | |
1da177e4 | 117 | |
d945cb9c | 118 | if (tty->stopped) |
1da177e4 | 119 | return 0; |
d945cb9c | 120 | |
d945cb9c AC |
121 | if (c > 0) { |
122 | /* Stuff the data into the input queue of the other end */ | |
123 | c = tty_insert_flip_string(to, buf, c); | |
124 | /* And shovel */ | |
202c4675 LT |
125 | if (c) { |
126 | tty_flip_buffer_push(to); | |
127 | tty_wakeup(tty); | |
128 | } | |
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 | ||
26df6d13 | 174 | /* Send a signal to the slave */ |
175 | static int pty_signal(struct tty_struct *tty, int sig) | |
176 | { | |
177 | unsigned long flags; | |
178 | struct pid *pgrp; | |
179 | ||
180 | if (tty->link) { | |
181 | spin_lock_irqsave(&tty->link->ctrl_lock, flags); | |
182 | pgrp = get_pid(tty->link->pgrp); | |
183 | spin_unlock_irqrestore(&tty->link->ctrl_lock, flags); | |
184 | ||
185 | kill_pgrp(pgrp, sig, 1); | |
186 | put_pid(pgrp); | |
187 | } | |
188 | return 0; | |
189 | } | |
190 | ||
1da177e4 LT |
191 | static void pty_flush_buffer(struct tty_struct *tty) |
192 | { | |
193 | struct tty_struct *to = tty->link; | |
04f378b1 | 194 | unsigned long flags; |
fe9cd962 | 195 | |
1da177e4 LT |
196 | if (!to) |
197 | return; | |
d945cb9c | 198 | /* tty_buffer_flush(to); FIXME */ |
1da177e4 | 199 | if (to->packet) { |
04f378b1 | 200 | spin_lock_irqsave(&tty->ctrl_lock, flags); |
1da177e4 LT |
201 | tty->ctrl_status |= TIOCPKT_FLUSHWRITE; |
202 | wake_up_interruptible(&to->read_wait); | |
04f378b1 | 203 | spin_unlock_irqrestore(&tty->ctrl_lock, flags); |
1da177e4 LT |
204 | } |
205 | } | |
206 | ||
fe9cd962 | 207 | static int pty_open(struct tty_struct *tty, struct file *filp) |
1da177e4 LT |
208 | { |
209 | int retval = -ENODEV; | |
210 | ||
211 | if (!tty || !tty->link) | |
212 | goto out; | |
213 | ||
214 | retval = -EIO; | |
215 | if (test_bit(TTY_OTHER_CLOSED, &tty->flags)) | |
216 | goto out; | |
217 | if (test_bit(TTY_PTY_LOCK, &tty->link->flags)) | |
218 | goto out; | |
219 | if (tty->link->count != 1) | |
220 | goto out; | |
221 | ||
222 | clear_bit(TTY_OTHER_CLOSED, &tty->link->flags); | |
223 | set_bit(TTY_THROTTLED, &tty->flags); | |
1da177e4 LT |
224 | retval = 0; |
225 | out: | |
226 | return retval; | |
227 | } | |
228 | ||
fe9cd962 AC |
229 | static void pty_set_termios(struct tty_struct *tty, |
230 | struct ktermios *old_termios) | |
1da177e4 | 231 | { |
adc8d746 AC |
232 | tty->termios.c_cflag &= ~(CSIZE | PARENB); |
233 | tty->termios.c_cflag |= (CS8 | CREAD); | |
1da177e4 LT |
234 | } |
235 | ||
fc6f6238 AC |
236 | /** |
237 | * pty_do_resize - resize event | |
238 | * @tty: tty being resized | |
c774bda2 | 239 | * @ws: window size being set. |
fc6f6238 | 240 | * |
3ad2f3fb | 241 | * Update the termios variables and send the necessary signals to |
fc6f6238 AC |
242 | * peform a terminal resize correctly |
243 | */ | |
244 | ||
245 | int pty_resize(struct tty_struct *tty, struct winsize *ws) | |
246 | { | |
247 | struct pid *pgrp, *rpgrp; | |
248 | unsigned long flags; | |
249 | struct tty_struct *pty = tty->link; | |
250 | ||
251 | /* For a PTY we need to lock the tty side */ | |
252 | mutex_lock(&tty->termios_mutex); | |
253 | if (!memcmp(ws, &tty->winsize, sizeof(*ws))) | |
254 | goto done; | |
255 | ||
256 | /* Get the PID values and reference them so we can | |
257 | avoid holding the tty ctrl lock while sending signals. | |
258 | We need to lock these individually however. */ | |
259 | ||
260 | spin_lock_irqsave(&tty->ctrl_lock, flags); | |
261 | pgrp = get_pid(tty->pgrp); | |
262 | spin_unlock_irqrestore(&tty->ctrl_lock, flags); | |
263 | ||
264 | spin_lock_irqsave(&pty->ctrl_lock, flags); | |
265 | rpgrp = get_pid(pty->pgrp); | |
266 | spin_unlock_irqrestore(&pty->ctrl_lock, flags); | |
267 | ||
268 | if (pgrp) | |
269 | kill_pgrp(pgrp, SIGWINCH, 1); | |
270 | if (rpgrp != pgrp && rpgrp) | |
271 | kill_pgrp(rpgrp, SIGWINCH, 1); | |
272 | ||
273 | put_pid(pgrp); | |
274 | put_pid(rpgrp); | |
275 | ||
276 | tty->winsize = *ws; | |
277 | pty->winsize = *ws; /* Never used so will go away soon */ | |
278 | done: | |
279 | mutex_unlock(&tty->termios_mutex); | |
280 | return 0; | |
281 | } | |
282 | ||
d155255a AC |
283 | /** |
284 | * pty_common_install - set up the pty pair | |
285 | * @driver: the pty driver | |
286 | * @tty: the tty being instantiated | |
287 | * @bool: legacy, true if this is BSD style | |
288 | * | |
289 | * Perform the initial set up for the tty/pty pair. Called from the | |
290 | * tty layer when the port is first opened. | |
291 | * | |
292 | * Locking: the caller must hold the tty_mutex | |
293 | */ | |
5d249bc6 JS |
294 | static int pty_common_install(struct tty_driver *driver, struct tty_struct *tty, |
295 | bool legacy) | |
bf970ee4 AC |
296 | { |
297 | struct tty_struct *o_tty; | |
d03702a2 | 298 | struct tty_port *ports[2]; |
bf970ee4 | 299 | int idx = tty->index; |
5d249bc6 | 300 | int retval = -ENOMEM; |
bf970ee4 AC |
301 | |
302 | o_tty = alloc_tty_struct(); | |
6f9ea7ad JS |
303 | if (!o_tty) |
304 | goto err; | |
d03702a2 JS |
305 | ports[0] = kmalloc(sizeof **ports, GFP_KERNEL); |
306 | ports[1] = kmalloc(sizeof **ports, GFP_KERNEL); | |
6f9ea7ad | 307 | if (!ports[0] || !ports[1]) |
d03702a2 | 308 | goto err_free_tty; |
bf970ee4 AC |
309 | if (!try_module_get(driver->other->owner)) { |
310 | /* This cannot in fact currently happen */ | |
8a1b8d70 | 311 | goto err_free_tty; |
bf970ee4 AC |
312 | } |
313 | initialize_tty_struct(o_tty, driver->other, idx); | |
314 | ||
5d249bc6 JS |
315 | if (legacy) { |
316 | /* We always use new tty termios data so we can do this | |
317 | the easy way .. */ | |
318 | retval = tty_init_termios(tty); | |
319 | if (retval) | |
320 | goto err_deinit_tty; | |
321 | ||
322 | retval = tty_init_termios(o_tty); | |
323 | if (retval) | |
324 | goto err_free_termios; | |
325 | ||
326 | driver->other->ttys[idx] = o_tty; | |
327 | driver->ttys[idx] = tty; | |
328 | } else { | |
adc8d746 AC |
329 | memset(&tty->termios_locked, 0, sizeof(tty->termios_locked)); |
330 | tty->termios = driver->init_termios; | |
331 | memset(&o_tty->termios_locked, 0, sizeof(tty->termios_locked)); | |
332 | o_tty->termios = driver->other->init_termios; | |
5d249bc6 | 333 | } |
fe9cd962 | 334 | |
bf970ee4 AC |
335 | /* |
336 | * Everything allocated ... set up the o_tty structure. | |
337 | */ | |
bf970ee4 AC |
338 | tty_driver_kref_get(driver->other); |
339 | if (driver->subtype == PTY_TYPE_MASTER) | |
340 | o_tty->count++; | |
341 | /* Establish the links in both directions */ | |
342 | tty->link = o_tty; | |
343 | o_tty->link = tty; | |
d03702a2 JS |
344 | tty_port_init(ports[0]); |
345 | tty_port_init(ports[1]); | |
346 | o_tty->port = ports[0]; | |
347 | tty->port = ports[1]; | |
bf970ee4 AC |
348 | |
349 | tty_driver_kref_get(driver); | |
350 | tty->count++; | |
bf970ee4 | 351 | return 0; |
8a1b8d70 | 352 | err_free_termios: |
5d249bc6 JS |
353 | if (legacy) |
354 | tty_free_termios(tty); | |
a9dccddb JS |
355 | err_deinit_tty: |
356 | deinitialize_tty_struct(o_tty); | |
bf970ee4 | 357 | module_put(o_tty->driver->owner); |
8a1b8d70 | 358 | err_free_tty: |
d03702a2 JS |
359 | kfree(ports[0]); |
360 | kfree(ports[1]); | |
bf970ee4 | 361 | free_tty_struct(o_tty); |
6f9ea7ad | 362 | err: |
8a1b8d70 | 363 | return retval; |
bf970ee4 AC |
364 | } |
365 | ||
d03702a2 JS |
366 | static void pty_cleanup(struct tty_struct *tty) |
367 | { | |
368 | kfree(tty->port); | |
369 | } | |
370 | ||
5d249bc6 JS |
371 | /* Traditional BSD devices */ |
372 | #ifdef CONFIG_LEGACY_PTYS | |
373 | ||
374 | static int pty_install(struct tty_driver *driver, struct tty_struct *tty) | |
375 | { | |
376 | return pty_common_install(driver, tty, true); | |
377 | } | |
378 | ||
d155255a AC |
379 | static void pty_remove(struct tty_driver *driver, struct tty_struct *tty) |
380 | { | |
381 | struct tty_struct *pair = tty->link; | |
382 | driver->ttys[tty->index] = NULL; | |
383 | if (pair) | |
384 | pair->driver->ttys[pair->index] = NULL; | |
385 | } | |
386 | ||
6caa76b7 | 387 | static int pty_bsd_ioctl(struct tty_struct *tty, |
1da177e4 LT |
388 | unsigned int cmd, unsigned long arg) |
389 | { | |
390 | switch (cmd) { | |
391 | case TIOCSPTLCK: /* Set PT Lock (disallow slave open) */ | |
392 | return pty_set_lock(tty, (int __user *) arg); | |
26df6d13 | 393 | case TIOCSIG: /* Send signal to other side of pty */ |
394 | return pty_signal(tty, (int) arg); | |
1da177e4 LT |
395 | } |
396 | return -ENOIOCTLCMD; | |
397 | } | |
398 | ||
dc8c8587 KS |
399 | static int legacy_count = CONFIG_LEGACY_PTY_COUNT; |
400 | module_param(legacy_count, int, 0); | |
401 | ||
342a5971 LT |
402 | /* |
403 | * The master side of a pty can do TIOCSPTLCK and thus | |
404 | * has pty_bsd_ioctl. | |
405 | */ | |
406 | static const struct tty_operations master_pty_ops_bsd = { | |
407 | .install = pty_install, | |
3e8e88ca AC |
408 | .open = pty_open, |
409 | .close = pty_close, | |
410 | .write = pty_write, | |
411 | .write_room = pty_write_room, | |
412 | .flush_buffer = pty_flush_buffer, | |
413 | .chars_in_buffer = pty_chars_in_buffer, | |
414 | .unthrottle = pty_unthrottle, | |
415 | .set_termios = pty_set_termios, | |
416 | .ioctl = pty_bsd_ioctl, | |
d03702a2 | 417 | .cleanup = pty_cleanup, |
d155255a AC |
418 | .resize = pty_resize, |
419 | .remove = pty_remove | |
3e8e88ca AC |
420 | }; |
421 | ||
342a5971 LT |
422 | static const struct tty_operations slave_pty_ops_bsd = { |
423 | .install = pty_install, | |
424 | .open = pty_open, | |
425 | .close = pty_close, | |
426 | .write = pty_write, | |
427 | .write_room = pty_write_room, | |
428 | .flush_buffer = pty_flush_buffer, | |
429 | .chars_in_buffer = pty_chars_in_buffer, | |
430 | .unthrottle = pty_unthrottle, | |
431 | .set_termios = pty_set_termios, | |
d03702a2 | 432 | .cleanup = pty_cleanup, |
d155255a AC |
433 | .resize = pty_resize, |
434 | .remove = pty_remove | |
342a5971 LT |
435 | }; |
436 | ||
1da177e4 LT |
437 | static void __init legacy_pty_init(void) |
438 | { | |
342a5971 LT |
439 | struct tty_driver *pty_driver, *pty_slave_driver; |
440 | ||
dc8c8587 KS |
441 | if (legacy_count <= 0) |
442 | return; | |
1da177e4 | 443 | |
21aca2fa JS |
444 | pty_driver = tty_alloc_driver(legacy_count, |
445 | TTY_DRIVER_RESET_TERMIOS | | |
446 | TTY_DRIVER_REAL_RAW | | |
447 | TTY_DRIVER_DYNAMIC_ALLOC); | |
c3a6344a | 448 | if (IS_ERR(pty_driver)) |
1da177e4 LT |
449 | panic("Couldn't allocate pty driver"); |
450 | ||
21aca2fa JS |
451 | pty_slave_driver = tty_alloc_driver(legacy_count, |
452 | TTY_DRIVER_RESET_TERMIOS | | |
453 | TTY_DRIVER_REAL_RAW | | |
454 | TTY_DRIVER_DYNAMIC_ALLOC); | |
c3a6344a | 455 | if (IS_ERR(pty_slave_driver)) |
1da177e4 LT |
456 | panic("Couldn't allocate pty slave driver"); |
457 | ||
1da177e4 LT |
458 | pty_driver->driver_name = "pty_master"; |
459 | pty_driver->name = "pty"; | |
1da177e4 LT |
460 | pty_driver->major = PTY_MASTER_MAJOR; |
461 | pty_driver->minor_start = 0; | |
462 | pty_driver->type = TTY_DRIVER_TYPE_PTY; | |
463 | pty_driver->subtype = PTY_TYPE_MASTER; | |
464 | pty_driver->init_termios = tty_std_termios; | |
465 | pty_driver->init_termios.c_iflag = 0; | |
466 | pty_driver->init_termios.c_oflag = 0; | |
467 | pty_driver->init_termios.c_cflag = B38400 | CS8 | CREAD; | |
468 | pty_driver->init_termios.c_lflag = 0; | |
606d099c AC |
469 | pty_driver->init_termios.c_ispeed = 38400; |
470 | pty_driver->init_termios.c_ospeed = 38400; | |
1da177e4 | 471 | pty_driver->other = pty_slave_driver; |
342a5971 | 472 | tty_set_operations(pty_driver, &master_pty_ops_bsd); |
1da177e4 | 473 | |
1da177e4 LT |
474 | pty_slave_driver->driver_name = "pty_slave"; |
475 | pty_slave_driver->name = "ttyp"; | |
1da177e4 LT |
476 | pty_slave_driver->major = PTY_SLAVE_MAJOR; |
477 | pty_slave_driver->minor_start = 0; | |
478 | pty_slave_driver->type = TTY_DRIVER_TYPE_PTY; | |
479 | pty_slave_driver->subtype = PTY_TYPE_SLAVE; | |
480 | pty_slave_driver->init_termios = tty_std_termios; | |
481 | pty_slave_driver->init_termios.c_cflag = B38400 | CS8 | CREAD; | |
606d099c AC |
482 | pty_slave_driver->init_termios.c_ispeed = 38400; |
483 | pty_slave_driver->init_termios.c_ospeed = 38400; | |
1da177e4 | 484 | pty_slave_driver->other = pty_driver; |
342a5971 | 485 | tty_set_operations(pty_slave_driver, &slave_pty_ops_bsd); |
1da177e4 LT |
486 | |
487 | if (tty_register_driver(pty_driver)) | |
488 | panic("Couldn't register pty driver"); | |
489 | if (tty_register_driver(pty_slave_driver)) | |
490 | panic("Couldn't register pty slave driver"); | |
491 | } | |
492 | #else | |
493 | static inline void legacy_pty_init(void) { } | |
494 | #endif | |
495 | ||
496 | /* Unix98 devices */ | |
497 | #ifdef CONFIG_UNIX98_PTYS | |
1da177e4 | 498 | |
d81ed103 AC |
499 | static struct cdev ptmx_cdev; |
500 | ||
6caa76b7 | 501 | static int pty_unix98_ioctl(struct tty_struct *tty, |
1da177e4 LT |
502 | unsigned int cmd, unsigned long arg) |
503 | { | |
504 | switch (cmd) { | |
505 | case TIOCSPTLCK: /* Set PT Lock (disallow slave open) */ | |
506 | return pty_set_lock(tty, (int __user *)arg); | |
507 | case TIOCGPTN: /* Get PT Number */ | |
508 | return put_user(tty->index, (unsigned int __user *)arg); | |
26df6d13 | 509 | case TIOCSIG: /* Send signal to other side of pty */ |
510 | return pty_signal(tty, (int) arg); | |
1da177e4 LT |
511 | } |
512 | ||
513 | return -ENOIOCTLCMD; | |
514 | } | |
515 | ||
99f1fe18 AC |
516 | /** |
517 | * ptm_unix98_lookup - find a pty master | |
518 | * @driver: ptm driver | |
519 | * @idx: tty index | |
520 | * | |
521 | * Look up a pty master device. Called under the tty_mutex for now. | |
522 | * This provides our locking. | |
523 | */ | |
524 | ||
15f1a633 SB |
525 | static struct tty_struct *ptm_unix98_lookup(struct tty_driver *driver, |
526 | struct inode *ptm_inode, int idx) | |
99f1fe18 | 527 | { |
593a27c4 KK |
528 | /* Master must be open via /dev/ptmx */ |
529 | return ERR_PTR(-EIO); | |
99f1fe18 AC |
530 | } |
531 | ||
532 | /** | |
533 | * pts_unix98_lookup - find a pty slave | |
534 | * @driver: pts driver | |
535 | * @idx: tty index | |
536 | * | |
537 | * Look up a pty master device. Called under the tty_mutex for now. | |
d739e65b | 538 | * This provides our locking for the tty pointer. |
99f1fe18 AC |
539 | */ |
540 | ||
15f1a633 SB |
541 | static struct tty_struct *pts_unix98_lookup(struct tty_driver *driver, |
542 | struct inode *pts_inode, int idx) | |
99f1fe18 | 543 | { |
d739e65b AC |
544 | struct tty_struct *tty; |
545 | ||
546 | mutex_lock(&devpts_mutex); | |
8fcbaa2b | 547 | tty = devpts_get_priv(pts_inode); |
d739e65b | 548 | mutex_unlock(&devpts_mutex); |
99f1fe18 AC |
549 | /* Master must be open before slave */ |
550 | if (!tty) | |
551 | return ERR_PTR(-EIO); | |
552 | return tty; | |
553 | } | |
554 | ||
8b0a88d5 AC |
555 | /* We have no need to install and remove our tty objects as devpts does all |
556 | the work for us */ | |
557 | ||
bf970ee4 | 558 | static int pty_unix98_install(struct tty_driver *driver, struct tty_struct *tty) |
8b0a88d5 | 559 | { |
5d249bc6 | 560 | return pty_common_install(driver, tty, false); |
8b0a88d5 AC |
561 | } |
562 | ||
7171604a | 563 | static void pty_unix98_remove(struct tty_driver *driver, struct tty_struct *tty) |
8b0a88d5 AC |
564 | { |
565 | } | |
566 | ||
feebed65 | 567 | static const struct tty_operations ptm_unix98_ops = { |
99f1fe18 | 568 | .lookup = ptm_unix98_lookup, |
bf970ee4 | 569 | .install = pty_unix98_install, |
7171604a | 570 | .remove = pty_unix98_remove, |
3e8e88ca AC |
571 | .open = pty_open, |
572 | .close = pty_close, | |
573 | .write = pty_write, | |
574 | .write_room = pty_write_room, | |
575 | .flush_buffer = pty_flush_buffer, | |
576 | .chars_in_buffer = pty_chars_in_buffer, | |
577 | .unthrottle = pty_unthrottle, | |
578 | .set_termios = pty_set_termios, | |
feebed65 | 579 | .ioctl = pty_unix98_ioctl, |
36b3c070 AC |
580 | .resize = pty_resize, |
581 | .cleanup = pty_cleanup | |
3e8e88ca AC |
582 | }; |
583 | ||
99f1fe18 AC |
584 | static const struct tty_operations pty_unix98_ops = { |
585 | .lookup = pts_unix98_lookup, | |
bf970ee4 | 586 | .install = pty_unix98_install, |
7171604a | 587 | .remove = pty_unix98_remove, |
99f1fe18 AC |
588 | .open = pty_open, |
589 | .close = pty_close, | |
590 | .write = pty_write, | |
591 | .write_room = pty_write_room, | |
592 | .flush_buffer = pty_flush_buffer, | |
593 | .chars_in_buffer = pty_chars_in_buffer, | |
594 | .unthrottle = pty_unthrottle, | |
595 | .set_termios = pty_set_termios, | |
d03702a2 | 596 | .cleanup = pty_cleanup, |
99f1fe18 | 597 | }; |
d81ed103 AC |
598 | |
599 | /** | |
600 | * ptmx_open - open a unix 98 pty master | |
601 | * @inode: inode of device file | |
602 | * @filp: file pointer to tty | |
603 | * | |
604 | * Allocate a unix98 pty master device from the ptmx driver. | |
605 | * | |
606 | * Locking: tty_mutex protects the init_dev work. tty->count should | |
607 | * protect the rest. | |
608 | * allocated_ptys_lock handles the list of free pty numbers | |
609 | */ | |
610 | ||
64ba3dc3 | 611 | static int ptmx_open(struct inode *inode, struct file *filp) |
d81ed103 AC |
612 | { |
613 | struct tty_struct *tty; | |
162b97cf | 614 | struct inode *slave_inode; |
d81ed103 AC |
615 | int retval; |
616 | int index; | |
617 | ||
618 | nonseekable_open(inode, filp); | |
619 | ||
fa90e1c9 JS |
620 | retval = tty_alloc_file(filp); |
621 | if (retval) | |
622 | return retval; | |
623 | ||
d81ed103 | 624 | /* find a device that is not in use. */ |
89c8d91e | 625 | mutex_lock(&devpts_mutex); |
15f1a633 | 626 | index = devpts_new_index(inode); |
fa90e1c9 JS |
627 | if (index < 0) { |
628 | retval = index; | |
05fb79e4 | 629 | mutex_unlock(&devpts_mutex); |
fa90e1c9 JS |
630 | goto err_file; |
631 | } | |
d81ed103 | 632 | |
89c8d91e AC |
633 | mutex_unlock(&devpts_mutex); |
634 | ||
d81ed103 | 635 | mutex_lock(&tty_mutex); |
593a27c4 | 636 | tty = tty_init_dev(ptm_driver, index); |
d81ed103 | 637 | |
73ec06fc AC |
638 | if (IS_ERR(tty)) { |
639 | retval = PTR_ERR(tty); | |
d81ed103 | 640 | goto out; |
73ec06fc | 641 | } |
d81ed103 | 642 | |
89c8d91e AC |
643 | /* The tty returned here is locked so we can safely |
644 | drop the mutex */ | |
645 | mutex_unlock(&tty_mutex); | |
646 | ||
d81ed103 | 647 | set_bit(TTY_PTY_LOCK, &tty->flags); /* LOCK THE SLAVE */ |
ee2ffa0d | 648 | |
fa90e1c9 | 649 | tty_add_file(tty, filp); |
d81ed103 | 650 | |
f11afb61 JS |
651 | slave_inode = devpts_pty_new(inode, |
652 | MKDEV(UNIX98_PTY_SLAVE_MAJOR, index), index, | |
653 | tty->link); | |
162b97cf JS |
654 | if (IS_ERR(slave_inode)) { |
655 | retval = PTR_ERR(slave_inode); | |
1177c0ef | 656 | goto err_release; |
162b97cf | 657 | } |
d81ed103 AC |
658 | |
659 | retval = ptm_driver->ops->open(tty, filp); | |
64ba3dc3 | 660 | if (retval) |
1177c0ef JS |
661 | goto err_release; |
662 | ||
89c8d91e | 663 | tty_unlock(tty); |
f11afb61 | 664 | tty->link->driver_data = slave_inode; |
1177c0ef JS |
665 | return 0; |
666 | err_release: | |
89c8d91e | 667 | tty_unlock(tty); |
eeb89d91 | 668 | tty_release(inode, filp); |
d81ed103 AC |
669 | return retval; |
670 | out: | |
89c8d91e | 671 | mutex_unlock(&tty_mutex); |
d3bda529 | 672 | devpts_kill_index(inode, index); |
fa90e1c9 JS |
673 | err_file: |
674 | tty_free_file(filp); | |
64ba3dc3 | 675 | return retval; |
d81ed103 AC |
676 | } |
677 | ||
678 | static struct file_operations ptmx_fops; | |
679 | ||
1da177e4 LT |
680 | static void __init unix98_pty_init(void) |
681 | { | |
21aca2fa JS |
682 | ptm_driver = tty_alloc_driver(NR_UNIX98_PTY_MAX, |
683 | TTY_DRIVER_RESET_TERMIOS | | |
684 | TTY_DRIVER_REAL_RAW | | |
685 | TTY_DRIVER_DYNAMIC_DEV | | |
686 | TTY_DRIVER_DEVPTS_MEM | | |
687 | TTY_DRIVER_DYNAMIC_ALLOC); | |
c3a6344a | 688 | if (IS_ERR(ptm_driver)) |
1da177e4 | 689 | panic("Couldn't allocate Unix98 ptm driver"); |
21aca2fa JS |
690 | pts_driver = tty_alloc_driver(NR_UNIX98_PTY_MAX, |
691 | TTY_DRIVER_RESET_TERMIOS | | |
692 | TTY_DRIVER_REAL_RAW | | |
693 | TTY_DRIVER_DYNAMIC_DEV | | |
694 | TTY_DRIVER_DEVPTS_MEM | | |
695 | TTY_DRIVER_DYNAMIC_ALLOC); | |
c3a6344a | 696 | if (IS_ERR(pts_driver)) |
1da177e4 LT |
697 | panic("Couldn't allocate Unix98 pts driver"); |
698 | ||
1da177e4 LT |
699 | ptm_driver->driver_name = "pty_master"; |
700 | ptm_driver->name = "ptm"; | |
701 | ptm_driver->major = UNIX98_PTY_MASTER_MAJOR; | |
702 | ptm_driver->minor_start = 0; | |
703 | ptm_driver->type = TTY_DRIVER_TYPE_PTY; | |
704 | ptm_driver->subtype = PTY_TYPE_MASTER; | |
705 | ptm_driver->init_termios = tty_std_termios; | |
706 | ptm_driver->init_termios.c_iflag = 0; | |
707 | ptm_driver->init_termios.c_oflag = 0; | |
708 | ptm_driver->init_termios.c_cflag = B38400 | CS8 | CREAD; | |
709 | ptm_driver->init_termios.c_lflag = 0; | |
606d099c AC |
710 | ptm_driver->init_termios.c_ispeed = 38400; |
711 | ptm_driver->init_termios.c_ospeed = 38400; | |
1da177e4 | 712 | ptm_driver->other = pts_driver; |
feebed65 | 713 | tty_set_operations(ptm_driver, &ptm_unix98_ops); |
1da177e4 | 714 | |
1da177e4 LT |
715 | pts_driver->driver_name = "pty_slave"; |
716 | pts_driver->name = "pts"; | |
717 | pts_driver->major = UNIX98_PTY_SLAVE_MAJOR; | |
718 | pts_driver->minor_start = 0; | |
719 | pts_driver->type = TTY_DRIVER_TYPE_PTY; | |
720 | pts_driver->subtype = PTY_TYPE_SLAVE; | |
721 | pts_driver->init_termios = tty_std_termios; | |
722 | pts_driver->init_termios.c_cflag = B38400 | CS8 | CREAD; | |
606d099c AC |
723 | pts_driver->init_termios.c_ispeed = 38400; |
724 | pts_driver->init_termios.c_ospeed = 38400; | |
1da177e4 | 725 | pts_driver->other = ptm_driver; |
99f1fe18 | 726 | tty_set_operations(pts_driver, &pty_unix98_ops); |
fe9cd962 | 727 | |
1da177e4 LT |
728 | if (tty_register_driver(ptm_driver)) |
729 | panic("Couldn't register Unix98 ptm driver"); | |
730 | if (tty_register_driver(pts_driver)) | |
731 | panic("Couldn't register Unix98 pts driver"); | |
732 | ||
d81ed103 AC |
733 | /* Now create the /dev/ptmx special device */ |
734 | tty_default_fops(&ptmx_fops); | |
735 | ptmx_fops.open = ptmx_open; | |
736 | ||
737 | cdev_init(&ptmx_cdev, &ptmx_fops); | |
738 | if (cdev_add(&ptmx_cdev, MKDEV(TTYAUX_MAJOR, 2), 1) || | |
739 | register_chrdev_region(MKDEV(TTYAUX_MAJOR, 2), 1, "/dev/ptmx") < 0) | |
740 | panic("Couldn't register /dev/ptmx driver\n"); | |
741 | device_create(tty_class, NULL, MKDEV(TTYAUX_MAJOR, 2), NULL, "ptmx"); | |
1da177e4 | 742 | } |
d81ed103 | 743 | |
1da177e4 LT |
744 | #else |
745 | static inline void unix98_pty_init(void) { } | |
746 | #endif | |
747 | ||
748 | static int __init pty_init(void) | |
749 | { | |
750 | legacy_pty_init(); | |
751 | unix98_pty_init(); | |
752 | return 0; | |
753 | } | |
754 | module_init(pty_init); |