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 | 10 | #include <linux/errno.h> |
1da177e4 LT |
11 | #include <linux/interrupt.h> |
12 | #include <linux/tty.h> | |
13 | #include <linux/tty_flip.h> | |
14 | #include <linux/fcntl.h> | |
d43c36dc | 15 | #include <linux/sched.h> |
1da177e4 LT |
16 | #include <linux/string.h> |
17 | #include <linux/major.h> | |
18 | #include <linux/mm.h> | |
19 | #include <linux/init.h> | |
d81ed103 | 20 | #include <linux/device.h> |
fe9cd962 | 21 | #include <linux/uaccess.h> |
1da177e4 LT |
22 | #include <linux/bitops.h> |
23 | #include <linux/devpts_fs.h> | |
5a0e3ad6 | 24 | #include <linux/slab.h> |
d739e65b | 25 | #include <linux/mutex.h> |
01adc807 | 26 | #include <linux/poll.h> |
1da177e4 | 27 | |
d6847793 PH |
28 | #undef TTY_DEBUG_HANGUP |
29 | #ifdef TTY_DEBUG_HANGUP | |
30 | # define tty_debug_hangup(tty, f, args...) tty_debug(tty, f, ##args) | |
31 | #else | |
32 | # define tty_debug_hangup(tty, f, args...) do {} while (0) | |
33 | #endif | |
fe9cd962 | 34 | |
1da177e4 | 35 | #ifdef CONFIG_UNIX98_PTYS |
da2bdf9a | 36 | static struct tty_driver *ptm_driver; |
1da177e4 | 37 | static struct tty_driver *pts_driver; |
d739e65b | 38 | static DEFINE_MUTEX(devpts_mutex); |
1da177e4 LT |
39 | #endif |
40 | ||
fe9cd962 | 41 | static void pty_close(struct tty_struct *tty, struct file *filp) |
1da177e4 | 42 | { |
fe9cd962 AC |
43 | BUG_ON(!tty); |
44 | if (tty->driver->subtype == PTY_TYPE_MASTER) | |
45 | WARN_ON(tty->count > 1); | |
46 | else { | |
69939035 PH |
47 | if (test_bit(TTY_IO_ERROR, &tty->flags)) |
48 | return; | |
1da177e4 LT |
49 | if (tty->count > 2) |
50 | return; | |
51 | } | |
69939035 | 52 | set_bit(TTY_IO_ERROR, &tty->flags); |
1da177e4 LT |
53 | wake_up_interruptible(&tty->read_wait); |
54 | wake_up_interruptible(&tty->write_wait); | |
4ed60fc2 | 55 | spin_lock_irq(&tty->ctrl_lock); |
1da177e4 | 56 | tty->packet = 0; |
4ed60fc2 | 57 | spin_unlock_irq(&tty->ctrl_lock); |
89c8d91e | 58 | /* Review - krefs on tty_link ?? */ |
1da177e4 LT |
59 | if (!tty->link) |
60 | return; | |
1da177e4 | 61 | set_bit(TTY_OTHER_CLOSED, &tty->link->flags); |
1a48632f | 62 | tty_flip_buffer_push(tty->link->port); |
1da177e4 LT |
63 | wake_up_interruptible(&tty->link->write_wait); |
64 | if (tty->driver->subtype == PTY_TYPE_MASTER) { | |
65 | set_bit(TTY_OTHER_CLOSED, &tty->flags); | |
ce1000dd | 66 | #ifdef CONFIG_UNIX98_PTYS |
d739e65b | 67 | if (tty->driver == ptm_driver) { |
b9f8033f | 68 | mutex_lock(&devpts_mutex); |
7acf6cd8 PH |
69 | if (tty->link->driver_data) |
70 | devpts_pty_kill(tty->link->driver_data); | |
b9f8033f | 71 | mutex_unlock(&devpts_mutex); |
d739e65b | 72 | } |
ce1000dd | 73 | #endif |
11dbf203 | 74 | tty_vhangup(tty->link); |
1da177e4 LT |
75 | } |
76 | } | |
77 | ||
78 | /* | |
79 | * The unthrottle routine is called by the line discipline to signal | |
80 | * that it can receive more characters. For PTY's, the TTY_THROTTLED | |
81 | * flag is always set, to force the line discipline to always call the | |
fe9cd962 | 82 | * unthrottle routine when there are fewer than TTY_THRESHOLD_UNTHROTTLE |
1da177e4 LT |
83 | * characters in the queue. This is necessary since each time this |
84 | * happens, we need to wake up any sleeping processes that could be | |
85 | * (1) trying to send data to the pty, or (2) waiting in wait_until_sent() | |
86 | * for the pty buffer to be drained. | |
87 | */ | |
fe9cd962 | 88 | static void pty_unthrottle(struct tty_struct *tty) |
1da177e4 | 89 | { |
d945cb9c | 90 | tty_wakeup(tty->link); |
1da177e4 LT |
91 | set_bit(TTY_THROTTLED, &tty->flags); |
92 | } | |
93 | ||
d945cb9c AC |
94 | /** |
95 | * pty_write - write to a pty | |
96 | * @tty: the tty we write from | |
97 | * @buf: kernel buffer of data | |
98 | * @count: bytes to write | |
762faaed | 99 | * |
d945cb9c AC |
100 | * Our "hardware" write method. Data is coming from the ldisc which |
101 | * may be in a non sleeping state. We simply throw this at the other | |
102 | * end of the link as if we were an IRQ handler receiving stuff for | |
103 | * the other side of the pty/tty pair. | |
1da177e4 | 104 | */ |
d945cb9c | 105 | |
ac89a917 | 106 | static int pty_write(struct tty_struct *tty, const unsigned char *buf, int c) |
1da177e4 LT |
107 | { |
108 | struct tty_struct *to = tty->link; | |
1da177e4 | 109 | |
d945cb9c | 110 | if (tty->stopped) |
1da177e4 | 111 | return 0; |
d945cb9c | 112 | |
d945cb9c AC |
113 | if (c > 0) { |
114 | /* Stuff the data into the input queue of the other end */ | |
05c7cd39 | 115 | c = tty_insert_flip_string(to->port, buf, c); |
d945cb9c | 116 | /* And shovel */ |
5ede5253 | 117 | if (c) |
2e124b4a | 118 | tty_flip_buffer_push(to->port); |
762faaed | 119 | } |
1da177e4 LT |
120 | return c; |
121 | } | |
122 | ||
d945cb9c AC |
123 | /** |
124 | * pty_write_room - write space | |
125 | * @tty: tty we are writing from | |
126 | * | |
127 | * Report how many bytes the ldisc can send into the queue for | |
128 | * the other device. | |
129 | */ | |
130 | ||
1da177e4 LT |
131 | static int pty_write_room(struct tty_struct *tty) |
132 | { | |
85dfd81d LT |
133 | if (tty->stopped) |
134 | return 0; | |
c81622ac | 135 | return tty_buffer_space_avail(tty->link->port); |
1da177e4 LT |
136 | } |
137 | ||
d945cb9c AC |
138 | /** |
139 | * pty_chars_in_buffer - characters currently in our tx queue | |
140 | * @tty: our tty | |
fe9cd962 | 141 | * |
d945cb9c AC |
142 | * Report how much we have in the transmit queue. As everything is |
143 | * instantly at the other end this is easy to implement. | |
1da177e4 | 144 | */ |
d945cb9c | 145 | |
1da177e4 LT |
146 | static int pty_chars_in_buffer(struct tty_struct *tty) |
147 | { | |
d945cb9c | 148 | return 0; |
1da177e4 LT |
149 | } |
150 | ||
151 | /* Set the lock flag on a pty */ | |
fe9cd962 | 152 | static int pty_set_lock(struct tty_struct *tty, int __user *arg) |
1da177e4 LT |
153 | { |
154 | int val; | |
fe9cd962 | 155 | if (get_user(val, arg)) |
1da177e4 LT |
156 | return -EFAULT; |
157 | if (val) | |
158 | set_bit(TTY_PTY_LOCK, &tty->flags); | |
159 | else | |
160 | clear_bit(TTY_PTY_LOCK, &tty->flags); | |
161 | return 0; | |
162 | } | |
163 | ||
84fd7bdf CG |
164 | static int pty_get_lock(struct tty_struct *tty, int __user *arg) |
165 | { | |
166 | int locked = test_bit(TTY_PTY_LOCK, &tty->flags); | |
167 | return put_user(locked, arg); | |
168 | } | |
169 | ||
06026d91 CG |
170 | /* Set the packet mode on a pty */ |
171 | static int pty_set_pktmode(struct tty_struct *tty, int __user *arg) | |
172 | { | |
06026d91 CG |
173 | int pktmode; |
174 | ||
175 | if (get_user(pktmode, arg)) | |
176 | return -EFAULT; | |
177 | ||
6054c16e | 178 | spin_lock_irq(&tty->ctrl_lock); |
06026d91 CG |
179 | if (pktmode) { |
180 | if (!tty->packet) { | |
06026d91 | 181 | tty->link->ctrl_status = 0; |
2622d73e PH |
182 | smp_mb(); |
183 | tty->packet = 1; | |
06026d91 CG |
184 | } |
185 | } else | |
186 | tty->packet = 0; | |
6054c16e | 187 | spin_unlock_irq(&tty->ctrl_lock); |
06026d91 CG |
188 | |
189 | return 0; | |
190 | } | |
191 | ||
84fd7bdf CG |
192 | /* Get the packet mode of a pty */ |
193 | static int pty_get_pktmode(struct tty_struct *tty, int __user *arg) | |
194 | { | |
195 | int pktmode = tty->packet; | |
196 | return put_user(pktmode, arg); | |
197 | } | |
198 | ||
26df6d13 | 199 | /* Send a signal to the slave */ |
200 | static int pty_signal(struct tty_struct *tty, int sig) | |
201 | { | |
26df6d13 | 202 | struct pid *pgrp; |
203 | ||
37480a05 PH |
204 | if (sig != SIGINT && sig != SIGQUIT && sig != SIGTSTP) |
205 | return -EINVAL; | |
206 | ||
26df6d13 | 207 | if (tty->link) { |
5b239542 PH |
208 | pgrp = tty_get_pgrp(tty->link); |
209 | if (pgrp) | |
210 | kill_pgrp(pgrp, sig, 1); | |
26df6d13 | 211 | put_pid(pgrp); |
212 | } | |
213 | return 0; | |
214 | } | |
215 | ||
1da177e4 LT |
216 | static void pty_flush_buffer(struct tty_struct *tty) |
217 | { | |
218 | struct tty_struct *to = tty->link; | |
1d1d14da | 219 | struct tty_ldisc *ld; |
fe9cd962 | 220 | |
1da177e4 LT |
221 | if (!to) |
222 | return; | |
1d1d14da PH |
223 | |
224 | ld = tty_ldisc_ref(to); | |
225 | tty_buffer_flush(to, ld); | |
226 | if (ld) | |
227 | tty_ldisc_deref(ld); | |
228 | ||
1da177e4 | 229 | if (to->packet) { |
6054c16e | 230 | spin_lock_irq(&tty->ctrl_lock); |
1da177e4 LT |
231 | tty->ctrl_status |= TIOCPKT_FLUSHWRITE; |
232 | wake_up_interruptible(&to->read_wait); | |
6054c16e | 233 | spin_unlock_irq(&tty->ctrl_lock); |
1da177e4 LT |
234 | } |
235 | } | |
236 | ||
fe9cd962 | 237 | static int pty_open(struct tty_struct *tty, struct file *filp) |
1da177e4 | 238 | { |
1da177e4 | 239 | if (!tty || !tty->link) |
7c61c3d8 | 240 | return -ENODEV; |
69939035 | 241 | |
1da177e4 LT |
242 | if (test_bit(TTY_OTHER_CLOSED, &tty->flags)) |
243 | goto out; | |
244 | if (test_bit(TTY_PTY_LOCK, &tty->link->flags)) | |
245 | goto out; | |
80cace72 | 246 | if (tty->driver->subtype == PTY_TYPE_SLAVE && tty->link->count != 1) |
1da177e4 LT |
247 | goto out; |
248 | ||
69939035 | 249 | clear_bit(TTY_IO_ERROR, &tty->flags); |
1a48632f | 250 | /* TTY_OTHER_CLOSED must be cleared before TTY_OTHER_DONE */ |
1da177e4 | 251 | clear_bit(TTY_OTHER_CLOSED, &tty->link->flags); |
1a48632f | 252 | clear_bit(TTY_OTHER_DONE, &tty->link->flags); |
1da177e4 | 253 | set_bit(TTY_THROTTLED, &tty->flags); |
7c61c3d8 PH |
254 | return 0; |
255 | ||
1da177e4 | 256 | out: |
7c61c3d8 PH |
257 | set_bit(TTY_IO_ERROR, &tty->flags); |
258 | return -EIO; | |
1da177e4 LT |
259 | } |
260 | ||
fe9cd962 AC |
261 | static void pty_set_termios(struct tty_struct *tty, |
262 | struct ktermios *old_termios) | |
1da177e4 | 263 | { |
dbfcd851 PH |
264 | /* See if packet mode change of state. */ |
265 | if (tty->link && tty->link->packet) { | |
266 | int extproc = (old_termios->c_lflag & EXTPROC) | | |
267 | (tty->termios.c_lflag & EXTPROC); | |
268 | int old_flow = ((old_termios->c_iflag & IXON) && | |
269 | (old_termios->c_cc[VSTOP] == '\023') && | |
270 | (old_termios->c_cc[VSTART] == '\021')); | |
271 | int new_flow = (I_IXON(tty) && | |
272 | STOP_CHAR(tty) == '\023' && | |
273 | START_CHAR(tty) == '\021'); | |
274 | if ((old_flow != new_flow) || extproc) { | |
4d8c1dff | 275 | spin_lock_irq(&tty->ctrl_lock); |
dbfcd851 PH |
276 | if (old_flow != new_flow) { |
277 | tty->ctrl_status &= ~(TIOCPKT_DOSTOP | TIOCPKT_NOSTOP); | |
278 | if (new_flow) | |
279 | tty->ctrl_status |= TIOCPKT_DOSTOP; | |
280 | else | |
281 | tty->ctrl_status |= TIOCPKT_NOSTOP; | |
282 | } | |
283 | if (extproc) | |
284 | tty->ctrl_status |= TIOCPKT_IOCTL; | |
4d8c1dff | 285 | spin_unlock_irq(&tty->ctrl_lock); |
dbfcd851 PH |
286 | wake_up_interruptible(&tty->link->read_wait); |
287 | } | |
288 | } | |
289 | ||
adc8d746 AC |
290 | tty->termios.c_cflag &= ~(CSIZE | PARENB); |
291 | tty->termios.c_cflag |= (CS8 | CREAD); | |
1da177e4 LT |
292 | } |
293 | ||
fc6f6238 AC |
294 | /** |
295 | * pty_do_resize - resize event | |
296 | * @tty: tty being resized | |
c774bda2 | 297 | * @ws: window size being set. |
fc6f6238 | 298 | * |
3ad2f3fb | 299 | * Update the termios variables and send the necessary signals to |
fc6f6238 AC |
300 | * peform a terminal resize correctly |
301 | */ | |
302 | ||
159a8e92 | 303 | static int pty_resize(struct tty_struct *tty, struct winsize *ws) |
fc6f6238 AC |
304 | { |
305 | struct pid *pgrp, *rpgrp; | |
fc6f6238 AC |
306 | struct tty_struct *pty = tty->link; |
307 | ||
308 | /* For a PTY we need to lock the tty side */ | |
dee4a0be | 309 | mutex_lock(&tty->winsize_mutex); |
fc6f6238 AC |
310 | if (!memcmp(ws, &tty->winsize, sizeof(*ws))) |
311 | goto done; | |
312 | ||
5b239542 PH |
313 | /* Signal the foreground process group of both ptys */ |
314 | pgrp = tty_get_pgrp(tty); | |
315 | rpgrp = tty_get_pgrp(pty); | |
fc6f6238 AC |
316 | |
317 | if (pgrp) | |
318 | kill_pgrp(pgrp, SIGWINCH, 1); | |
319 | if (rpgrp != pgrp && rpgrp) | |
320 | kill_pgrp(rpgrp, SIGWINCH, 1); | |
321 | ||
322 | put_pid(pgrp); | |
323 | put_pid(rpgrp); | |
324 | ||
325 | tty->winsize = *ws; | |
326 | pty->winsize = *ws; /* Never used so will go away soon */ | |
327 | done: | |
dee4a0be | 328 | mutex_unlock(&tty->winsize_mutex); |
fc6f6238 AC |
329 | return 0; |
330 | } | |
331 | ||
01adc807 PH |
332 | /** |
333 | * pty_start - start() handler | |
334 | * pty_stop - stop() handler | |
335 | * @tty: tty being flow-controlled | |
336 | * | |
337 | * Propagates the TIOCPKT status to the master pty. | |
338 | * | |
339 | * NB: only the master pty can be in packet mode so only the slave | |
340 | * needs start()/stop() handlers | |
341 | */ | |
342 | static void pty_start(struct tty_struct *tty) | |
343 | { | |
344 | unsigned long flags; | |
345 | ||
01adc807 | 346 | if (tty->link && tty->link->packet) { |
54e8e5fc | 347 | spin_lock_irqsave(&tty->ctrl_lock, flags); |
01adc807 PH |
348 | tty->ctrl_status &= ~TIOCPKT_STOP; |
349 | tty->ctrl_status |= TIOCPKT_START; | |
54e8e5fc | 350 | spin_unlock_irqrestore(&tty->ctrl_lock, flags); |
01adc807 PH |
351 | wake_up_interruptible_poll(&tty->link->read_wait, POLLIN); |
352 | } | |
01adc807 PH |
353 | } |
354 | ||
355 | static void pty_stop(struct tty_struct *tty) | |
356 | { | |
357 | unsigned long flags; | |
358 | ||
01adc807 | 359 | if (tty->link && tty->link->packet) { |
54e8e5fc | 360 | spin_lock_irqsave(&tty->ctrl_lock, flags); |
01adc807 PH |
361 | tty->ctrl_status &= ~TIOCPKT_START; |
362 | tty->ctrl_status |= TIOCPKT_STOP; | |
54e8e5fc | 363 | spin_unlock_irqrestore(&tty->ctrl_lock, flags); |
01adc807 PH |
364 | wake_up_interruptible_poll(&tty->link->read_wait, POLLIN); |
365 | } | |
01adc807 PH |
366 | } |
367 | ||
d155255a AC |
368 | /** |
369 | * pty_common_install - set up the pty pair | |
370 | * @driver: the pty driver | |
371 | * @tty: the tty being instantiated | |
2c964a2f | 372 | * @legacy: true if this is BSD style |
d155255a AC |
373 | * |
374 | * Perform the initial set up for the tty/pty pair. Called from the | |
375 | * tty layer when the port is first opened. | |
376 | * | |
377 | * Locking: the caller must hold the tty_mutex | |
378 | */ | |
5d249bc6 JS |
379 | static int pty_common_install(struct tty_driver *driver, struct tty_struct *tty, |
380 | bool legacy) | |
bf970ee4 AC |
381 | { |
382 | struct tty_struct *o_tty; | |
d03702a2 | 383 | struct tty_port *ports[2]; |
bf970ee4 | 384 | int idx = tty->index; |
5d249bc6 | 385 | int retval = -ENOMEM; |
bf970ee4 | 386 | |
55199ea3 PH |
387 | /* Opening the slave first has always returned -EIO */ |
388 | if (driver->subtype != PTY_TYPE_MASTER) | |
389 | return -EIO; | |
390 | ||
d03702a2 JS |
391 | ports[0] = kmalloc(sizeof **ports, GFP_KERNEL); |
392 | ports[1] = kmalloc(sizeof **ports, GFP_KERNEL); | |
6f9ea7ad | 393 | if (!ports[0] || !ports[1]) |
2c964a2f | 394 | goto err; |
bf970ee4 AC |
395 | if (!try_module_get(driver->other->owner)) { |
396 | /* This cannot in fact currently happen */ | |
2c964a2f | 397 | goto err; |
bf970ee4 | 398 | } |
2c964a2f RV |
399 | o_tty = alloc_tty_struct(driver->other, idx); |
400 | if (!o_tty) | |
401 | goto err_put_module; | |
bf970ee4 | 402 | |
2febdb63 | 403 | tty_set_lock_subclass(o_tty); |
d2b6f447 | 404 | lockdep_set_subclass(&o_tty->termios_rwsem, TTY_LOCK_SLAVE); |
2febdb63 | 405 | |
5d249bc6 JS |
406 | if (legacy) { |
407 | /* We always use new tty termios data so we can do this | |
408 | the easy way .. */ | |
409 | retval = tty_init_termios(tty); | |
410 | if (retval) | |
411 | goto err_deinit_tty; | |
412 | ||
413 | retval = tty_init_termios(o_tty); | |
414 | if (retval) | |
415 | goto err_free_termios; | |
416 | ||
417 | driver->other->ttys[idx] = o_tty; | |
418 | driver->ttys[idx] = tty; | |
419 | } else { | |
adc8d746 AC |
420 | memset(&tty->termios_locked, 0, sizeof(tty->termios_locked)); |
421 | tty->termios = driver->init_termios; | |
422 | memset(&o_tty->termios_locked, 0, sizeof(tty->termios_locked)); | |
423 | o_tty->termios = driver->other->init_termios; | |
5d249bc6 | 424 | } |
fe9cd962 | 425 | |
bf970ee4 AC |
426 | /* |
427 | * Everything allocated ... set up the o_tty structure. | |
428 | */ | |
bf970ee4 | 429 | tty_driver_kref_get(driver->other); |
bf970ee4 AC |
430 | /* Establish the links in both directions */ |
431 | tty->link = o_tty; | |
432 | o_tty->link = tty; | |
d03702a2 JS |
433 | tty_port_init(ports[0]); |
434 | tty_port_init(ports[1]); | |
c81622ac PH |
435 | tty_buffer_set_limit(ports[0], 8192); |
436 | tty_buffer_set_limit(ports[1], 8192); | |
d03702a2 JS |
437 | o_tty->port = ports[0]; |
438 | tty->port = ports[1]; | |
967fab69 | 439 | o_tty->port->itty = o_tty; |
bf970ee4 | 440 | |
1d1d14da PH |
441 | tty_buffer_set_lock_subclass(o_tty->port); |
442 | ||
bf970ee4 AC |
443 | tty_driver_kref_get(driver); |
444 | tty->count++; | |
55199ea3 | 445 | o_tty->count++; |
bf970ee4 | 446 | return 0; |
8a1b8d70 | 447 | err_free_termios: |
5d249bc6 JS |
448 | if (legacy) |
449 | tty_free_termios(tty); | |
a9dccddb JS |
450 | err_deinit_tty: |
451 | deinitialize_tty_struct(o_tty); | |
2c964a2f RV |
452 | free_tty_struct(o_tty); |
453 | err_put_module: | |
07584d4a | 454 | module_put(driver->other->owner); |
2c964a2f | 455 | err: |
d03702a2 JS |
456 | kfree(ports[0]); |
457 | kfree(ports[1]); | |
8a1b8d70 | 458 | return retval; |
bf970ee4 AC |
459 | } |
460 | ||
d03702a2 JS |
461 | static void pty_cleanup(struct tty_struct *tty) |
462 | { | |
81c79838 | 463 | tty_port_put(tty->port); |
d03702a2 JS |
464 | } |
465 | ||
5d249bc6 JS |
466 | /* Traditional BSD devices */ |
467 | #ifdef CONFIG_LEGACY_PTYS | |
468 | ||
469 | static int pty_install(struct tty_driver *driver, struct tty_struct *tty) | |
470 | { | |
471 | return pty_common_install(driver, tty, true); | |
472 | } | |
473 | ||
d155255a AC |
474 | static void pty_remove(struct tty_driver *driver, struct tty_struct *tty) |
475 | { | |
476 | struct tty_struct *pair = tty->link; | |
477 | driver->ttys[tty->index] = NULL; | |
478 | if (pair) | |
479 | pair->driver->ttys[pair->index] = NULL; | |
480 | } | |
481 | ||
6caa76b7 | 482 | static int pty_bsd_ioctl(struct tty_struct *tty, |
1da177e4 LT |
483 | unsigned int cmd, unsigned long arg) |
484 | { | |
485 | switch (cmd) { | |
486 | case TIOCSPTLCK: /* Set PT Lock (disallow slave open) */ | |
487 | return pty_set_lock(tty, (int __user *) arg); | |
84fd7bdf CG |
488 | case TIOCGPTLCK: /* Get PT Lock status */ |
489 | return pty_get_lock(tty, (int __user *)arg); | |
06026d91 CG |
490 | case TIOCPKT: /* Set PT packet mode */ |
491 | return pty_set_pktmode(tty, (int __user *)arg); | |
84fd7bdf CG |
492 | case TIOCGPKT: /* Get PT packet mode */ |
493 | return pty_get_pktmode(tty, (int __user *)arg); | |
26df6d13 | 494 | case TIOCSIG: /* Send signal to other side of pty */ |
495 | return pty_signal(tty, (int) arg); | |
ded2f295 JS |
496 | case TIOCGPTN: /* TTY returns ENOTTY, but glibc expects EINVAL here */ |
497 | return -EINVAL; | |
1da177e4 LT |
498 | } |
499 | return -ENOIOCTLCMD; | |
500 | } | |
501 | ||
dc8c8587 | 502 | static int legacy_count = CONFIG_LEGACY_PTY_COUNT; |
7154988f PG |
503 | /* |
504 | * not really modular, but the easiest way to keep compat with existing | |
505 | * bootargs behaviour is to continue using module_param here. | |
506 | */ | |
dc8c8587 KS |
507 | module_param(legacy_count, int, 0); |
508 | ||
342a5971 LT |
509 | /* |
510 | * The master side of a pty can do TIOCSPTLCK and thus | |
511 | * has pty_bsd_ioctl. | |
512 | */ | |
513 | static const struct tty_operations master_pty_ops_bsd = { | |
514 | .install = pty_install, | |
3e8e88ca AC |
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, | |
3e8e88ca | 522 | .ioctl = pty_bsd_ioctl, |
d03702a2 | 523 | .cleanup = pty_cleanup, |
d155255a AC |
524 | .resize = pty_resize, |
525 | .remove = pty_remove | |
3e8e88ca AC |
526 | }; |
527 | ||
342a5971 LT |
528 | static const struct tty_operations slave_pty_ops_bsd = { |
529 | .install = pty_install, | |
530 | .open = pty_open, | |
531 | .close = pty_close, | |
532 | .write = pty_write, | |
533 | .write_room = pty_write_room, | |
534 | .flush_buffer = pty_flush_buffer, | |
535 | .chars_in_buffer = pty_chars_in_buffer, | |
536 | .unthrottle = pty_unthrottle, | |
537 | .set_termios = pty_set_termios, | |
d03702a2 | 538 | .cleanup = pty_cleanup, |
d155255a | 539 | .resize = pty_resize, |
01adc807 PH |
540 | .start = pty_start, |
541 | .stop = pty_stop, | |
d155255a | 542 | .remove = pty_remove |
342a5971 LT |
543 | }; |
544 | ||
1da177e4 LT |
545 | static void __init legacy_pty_init(void) |
546 | { | |
342a5971 LT |
547 | struct tty_driver *pty_driver, *pty_slave_driver; |
548 | ||
dc8c8587 KS |
549 | if (legacy_count <= 0) |
550 | return; | |
1da177e4 | 551 | |
21aca2fa JS |
552 | pty_driver = tty_alloc_driver(legacy_count, |
553 | TTY_DRIVER_RESET_TERMIOS | | |
554 | TTY_DRIVER_REAL_RAW | | |
555 | TTY_DRIVER_DYNAMIC_ALLOC); | |
c3a6344a | 556 | if (IS_ERR(pty_driver)) |
1da177e4 LT |
557 | panic("Couldn't allocate pty driver"); |
558 | ||
21aca2fa JS |
559 | pty_slave_driver = tty_alloc_driver(legacy_count, |
560 | TTY_DRIVER_RESET_TERMIOS | | |
561 | TTY_DRIVER_REAL_RAW | | |
562 | TTY_DRIVER_DYNAMIC_ALLOC); | |
c3a6344a | 563 | if (IS_ERR(pty_slave_driver)) |
1da177e4 LT |
564 | panic("Couldn't allocate pty slave driver"); |
565 | ||
1da177e4 LT |
566 | pty_driver->driver_name = "pty_master"; |
567 | pty_driver->name = "pty"; | |
1da177e4 LT |
568 | pty_driver->major = PTY_MASTER_MAJOR; |
569 | pty_driver->minor_start = 0; | |
570 | pty_driver->type = TTY_DRIVER_TYPE_PTY; | |
571 | pty_driver->subtype = PTY_TYPE_MASTER; | |
572 | pty_driver->init_termios = tty_std_termios; | |
573 | pty_driver->init_termios.c_iflag = 0; | |
574 | pty_driver->init_termios.c_oflag = 0; | |
575 | pty_driver->init_termios.c_cflag = B38400 | CS8 | CREAD; | |
576 | pty_driver->init_termios.c_lflag = 0; | |
606d099c AC |
577 | pty_driver->init_termios.c_ispeed = 38400; |
578 | pty_driver->init_termios.c_ospeed = 38400; | |
1da177e4 | 579 | pty_driver->other = pty_slave_driver; |
342a5971 | 580 | tty_set_operations(pty_driver, &master_pty_ops_bsd); |
1da177e4 | 581 | |
1da177e4 LT |
582 | pty_slave_driver->driver_name = "pty_slave"; |
583 | pty_slave_driver->name = "ttyp"; | |
1da177e4 LT |
584 | pty_slave_driver->major = PTY_SLAVE_MAJOR; |
585 | pty_slave_driver->minor_start = 0; | |
586 | pty_slave_driver->type = TTY_DRIVER_TYPE_PTY; | |
587 | pty_slave_driver->subtype = PTY_TYPE_SLAVE; | |
588 | pty_slave_driver->init_termios = tty_std_termios; | |
589 | pty_slave_driver->init_termios.c_cflag = B38400 | CS8 | CREAD; | |
606d099c AC |
590 | pty_slave_driver->init_termios.c_ispeed = 38400; |
591 | pty_slave_driver->init_termios.c_ospeed = 38400; | |
1da177e4 | 592 | pty_slave_driver->other = pty_driver; |
342a5971 | 593 | tty_set_operations(pty_slave_driver, &slave_pty_ops_bsd); |
1da177e4 LT |
594 | |
595 | if (tty_register_driver(pty_driver)) | |
596 | panic("Couldn't register pty driver"); | |
597 | if (tty_register_driver(pty_slave_driver)) | |
598 | panic("Couldn't register pty slave driver"); | |
599 | } | |
600 | #else | |
601 | static inline void legacy_pty_init(void) { } | |
602 | #endif | |
603 | ||
604 | /* Unix98 devices */ | |
605 | #ifdef CONFIG_UNIX98_PTYS | |
1da177e4 | 606 | |
d81ed103 AC |
607 | static struct cdev ptmx_cdev; |
608 | ||
6caa76b7 | 609 | static int pty_unix98_ioctl(struct tty_struct *tty, |
1da177e4 LT |
610 | unsigned int cmd, unsigned long arg) |
611 | { | |
612 | switch (cmd) { | |
613 | case TIOCSPTLCK: /* Set PT Lock (disallow slave open) */ | |
614 | return pty_set_lock(tty, (int __user *)arg); | |
84fd7bdf CG |
615 | case TIOCGPTLCK: /* Get PT Lock status */ |
616 | return pty_get_lock(tty, (int __user *)arg); | |
06026d91 CG |
617 | case TIOCPKT: /* Set PT packet mode */ |
618 | return pty_set_pktmode(tty, (int __user *)arg); | |
84fd7bdf CG |
619 | case TIOCGPKT: /* Get PT packet mode */ |
620 | return pty_get_pktmode(tty, (int __user *)arg); | |
1da177e4 LT |
621 | case TIOCGPTN: /* Get PT Number */ |
622 | return put_user(tty->index, (unsigned int __user *)arg); | |
26df6d13 | 623 | case TIOCSIG: /* Send signal to other side of pty */ |
624 | return pty_signal(tty, (int) arg); | |
1da177e4 LT |
625 | } |
626 | ||
627 | return -ENOIOCTLCMD; | |
628 | } | |
629 | ||
99f1fe18 AC |
630 | /** |
631 | * ptm_unix98_lookup - find a pty master | |
632 | * @driver: ptm driver | |
633 | * @idx: tty index | |
634 | * | |
635 | * Look up a pty master device. Called under the tty_mutex for now. | |
636 | * This provides our locking. | |
637 | */ | |
638 | ||
15f1a633 SB |
639 | static struct tty_struct *ptm_unix98_lookup(struct tty_driver *driver, |
640 | struct inode *ptm_inode, int idx) | |
99f1fe18 | 641 | { |
593a27c4 KK |
642 | /* Master must be open via /dev/ptmx */ |
643 | return ERR_PTR(-EIO); | |
99f1fe18 AC |
644 | } |
645 | ||
646 | /** | |
647 | * pts_unix98_lookup - find a pty slave | |
648 | * @driver: pts driver | |
649 | * @idx: tty index | |
650 | * | |
651 | * Look up a pty master device. Called under the tty_mutex for now. | |
d739e65b | 652 | * This provides our locking for the tty pointer. |
99f1fe18 AC |
653 | */ |
654 | ||
15f1a633 SB |
655 | static struct tty_struct *pts_unix98_lookup(struct tty_driver *driver, |
656 | struct inode *pts_inode, int idx) | |
99f1fe18 | 657 | { |
d739e65b AC |
658 | struct tty_struct *tty; |
659 | ||
660 | mutex_lock(&devpts_mutex); | |
8fcbaa2b | 661 | tty = devpts_get_priv(pts_inode); |
d739e65b | 662 | mutex_unlock(&devpts_mutex); |
99f1fe18 AC |
663 | /* Master must be open before slave */ |
664 | if (!tty) | |
665 | return ERR_PTR(-EIO); | |
666 | return tty; | |
667 | } | |
668 | ||
8b0a88d5 AC |
669 | /* We have no need to install and remove our tty objects as devpts does all |
670 | the work for us */ | |
671 | ||
bf970ee4 | 672 | static int pty_unix98_install(struct tty_driver *driver, struct tty_struct *tty) |
8b0a88d5 | 673 | { |
5d249bc6 | 674 | return pty_common_install(driver, tty, false); |
8b0a88d5 AC |
675 | } |
676 | ||
7171604a | 677 | static void pty_unix98_remove(struct tty_driver *driver, struct tty_struct *tty) |
8b0a88d5 AC |
678 | { |
679 | } | |
680 | ||
f4b208eb JS |
681 | /* this is called once with whichever end is closed last */ |
682 | static void pty_unix98_shutdown(struct tty_struct *tty) | |
683 | { | |
684 | devpts_kill_index(tty->driver_data, tty->index); | |
685 | } | |
686 | ||
feebed65 | 687 | static const struct tty_operations ptm_unix98_ops = { |
99f1fe18 | 688 | .lookup = ptm_unix98_lookup, |
bf970ee4 | 689 | .install = pty_unix98_install, |
7171604a | 690 | .remove = pty_unix98_remove, |
3e8e88ca AC |
691 | .open = pty_open, |
692 | .close = pty_close, | |
693 | .write = pty_write, | |
694 | .write_room = pty_write_room, | |
695 | .flush_buffer = pty_flush_buffer, | |
696 | .chars_in_buffer = pty_chars_in_buffer, | |
697 | .unthrottle = pty_unthrottle, | |
feebed65 | 698 | .ioctl = pty_unix98_ioctl, |
36b3c070 | 699 | .resize = pty_resize, |
fa2ecfc5 | 700 | .shutdown = pty_unix98_shutdown, |
36b3c070 | 701 | .cleanup = pty_cleanup |
3e8e88ca AC |
702 | }; |
703 | ||
99f1fe18 AC |
704 | static const struct tty_operations pty_unix98_ops = { |
705 | .lookup = pts_unix98_lookup, | |
bf970ee4 | 706 | .install = pty_unix98_install, |
7171604a | 707 | .remove = pty_unix98_remove, |
99f1fe18 AC |
708 | .open = pty_open, |
709 | .close = pty_close, | |
710 | .write = pty_write, | |
711 | .write_room = pty_write_room, | |
712 | .flush_buffer = pty_flush_buffer, | |
713 | .chars_in_buffer = pty_chars_in_buffer, | |
714 | .unthrottle = pty_unthrottle, | |
715 | .set_termios = pty_set_termios, | |
01adc807 PH |
716 | .start = pty_start, |
717 | .stop = pty_stop, | |
fa2ecfc5 | 718 | .shutdown = pty_unix98_shutdown, |
d03702a2 | 719 | .cleanup = pty_cleanup, |
99f1fe18 | 720 | }; |
d81ed103 AC |
721 | |
722 | /** | |
723 | * ptmx_open - open a unix 98 pty master | |
724 | * @inode: inode of device file | |
725 | * @filp: file pointer to tty | |
726 | * | |
727 | * Allocate a unix98 pty master device from the ptmx driver. | |
728 | * | |
729 | * Locking: tty_mutex protects the init_dev work. tty->count should | |
b9f8033f | 730 | * protect the rest. |
d81ed103 AC |
731 | * allocated_ptys_lock handles the list of free pty numbers |
732 | */ | |
733 | ||
64ba3dc3 | 734 | static int ptmx_open(struct inode *inode, struct file *filp) |
d81ed103 AC |
735 | { |
736 | struct tty_struct *tty; | |
162b97cf | 737 | struct inode *slave_inode; |
d81ed103 AC |
738 | int retval; |
739 | int index; | |
740 | ||
741 | nonseekable_open(inode, filp); | |
742 | ||
b0b88565 LT |
743 | /* We refuse fsnotify events on ptmx, since it's a shared resource */ |
744 | filp->f_mode |= FMODE_NONOTIFY; | |
745 | ||
fa90e1c9 JS |
746 | retval = tty_alloc_file(filp); |
747 | if (retval) | |
748 | return retval; | |
749 | ||
d81ed103 | 750 | /* find a device that is not in use. */ |
89c8d91e | 751 | mutex_lock(&devpts_mutex); |
15f1a633 | 752 | index = devpts_new_index(inode); |
fa90e1c9 JS |
753 | if (index < 0) { |
754 | retval = index; | |
05fb79e4 | 755 | mutex_unlock(&devpts_mutex); |
fa90e1c9 JS |
756 | goto err_file; |
757 | } | |
d81ed103 | 758 | |
89c8d91e AC |
759 | mutex_unlock(&devpts_mutex); |
760 | ||
d81ed103 | 761 | mutex_lock(&tty_mutex); |
593a27c4 | 762 | tty = tty_init_dev(ptm_driver, index); |
d81ed103 | 763 | |
73ec06fc AC |
764 | if (IS_ERR(tty)) { |
765 | retval = PTR_ERR(tty); | |
d81ed103 | 766 | goto out; |
73ec06fc | 767 | } |
d81ed103 | 768 | |
89c8d91e AC |
769 | /* The tty returned here is locked so we can safely |
770 | drop the mutex */ | |
771 | mutex_unlock(&tty_mutex); | |
772 | ||
d81ed103 | 773 | set_bit(TTY_PTY_LOCK, &tty->flags); /* LOCK THE SLAVE */ |
7acf6cd8 | 774 | tty->driver_data = inode; |
ee2ffa0d | 775 | |
fa90e1c9 | 776 | tty_add_file(tty, filp); |
d81ed103 | 777 | |
f11afb61 JS |
778 | slave_inode = devpts_pty_new(inode, |
779 | MKDEV(UNIX98_PTY_SLAVE_MAJOR, index), index, | |
780 | tty->link); | |
162b97cf JS |
781 | if (IS_ERR(slave_inode)) { |
782 | retval = PTR_ERR(slave_inode); | |
1177c0ef | 783 | goto err_release; |
162b97cf | 784 | } |
7acf6cd8 | 785 | tty->link->driver_data = slave_inode; |
d81ed103 AC |
786 | |
787 | retval = ptm_driver->ops->open(tty, filp); | |
64ba3dc3 | 788 | if (retval) |
1177c0ef JS |
789 | goto err_release; |
790 | ||
d6847793 PH |
791 | tty_debug_hangup(tty, "(tty count=%d)\n", tty->count); |
792 | ||
89c8d91e | 793 | tty_unlock(tty); |
1177c0ef JS |
794 | return 0; |
795 | err_release: | |
89c8d91e | 796 | tty_unlock(tty); |
eeb89d91 | 797 | tty_release(inode, filp); |
d81ed103 AC |
798 | return retval; |
799 | out: | |
89c8d91e | 800 | mutex_unlock(&tty_mutex); |
d3bda529 | 801 | devpts_kill_index(inode, index); |
fa90e1c9 JS |
802 | err_file: |
803 | tty_free_file(filp); | |
64ba3dc3 | 804 | return retval; |
d81ed103 AC |
805 | } |
806 | ||
807 | static struct file_operations ptmx_fops; | |
808 | ||
1da177e4 LT |
809 | static void __init unix98_pty_init(void) |
810 | { | |
21aca2fa JS |
811 | ptm_driver = tty_alloc_driver(NR_UNIX98_PTY_MAX, |
812 | TTY_DRIVER_RESET_TERMIOS | | |
813 | TTY_DRIVER_REAL_RAW | | |
814 | TTY_DRIVER_DYNAMIC_DEV | | |
815 | TTY_DRIVER_DEVPTS_MEM | | |
816 | TTY_DRIVER_DYNAMIC_ALLOC); | |
c3a6344a | 817 | if (IS_ERR(ptm_driver)) |
1da177e4 | 818 | panic("Couldn't allocate Unix98 ptm driver"); |
21aca2fa JS |
819 | pts_driver = tty_alloc_driver(NR_UNIX98_PTY_MAX, |
820 | TTY_DRIVER_RESET_TERMIOS | | |
821 | TTY_DRIVER_REAL_RAW | | |
822 | TTY_DRIVER_DYNAMIC_DEV | | |
823 | TTY_DRIVER_DEVPTS_MEM | | |
824 | TTY_DRIVER_DYNAMIC_ALLOC); | |
c3a6344a | 825 | if (IS_ERR(pts_driver)) |
1da177e4 LT |
826 | panic("Couldn't allocate Unix98 pts driver"); |
827 | ||
1da177e4 LT |
828 | ptm_driver->driver_name = "pty_master"; |
829 | ptm_driver->name = "ptm"; | |
830 | ptm_driver->major = UNIX98_PTY_MASTER_MAJOR; | |
831 | ptm_driver->minor_start = 0; | |
832 | ptm_driver->type = TTY_DRIVER_TYPE_PTY; | |
833 | ptm_driver->subtype = PTY_TYPE_MASTER; | |
834 | ptm_driver->init_termios = tty_std_termios; | |
835 | ptm_driver->init_termios.c_iflag = 0; | |
836 | ptm_driver->init_termios.c_oflag = 0; | |
837 | ptm_driver->init_termios.c_cflag = B38400 | CS8 | CREAD; | |
838 | ptm_driver->init_termios.c_lflag = 0; | |
606d099c AC |
839 | ptm_driver->init_termios.c_ispeed = 38400; |
840 | ptm_driver->init_termios.c_ospeed = 38400; | |
1da177e4 | 841 | ptm_driver->other = pts_driver; |
feebed65 | 842 | tty_set_operations(ptm_driver, &ptm_unix98_ops); |
1da177e4 | 843 | |
1da177e4 LT |
844 | pts_driver->driver_name = "pty_slave"; |
845 | pts_driver->name = "pts"; | |
846 | pts_driver->major = UNIX98_PTY_SLAVE_MAJOR; | |
847 | pts_driver->minor_start = 0; | |
848 | pts_driver->type = TTY_DRIVER_TYPE_PTY; | |
849 | pts_driver->subtype = PTY_TYPE_SLAVE; | |
850 | pts_driver->init_termios = tty_std_termios; | |
851 | pts_driver->init_termios.c_cflag = B38400 | CS8 | CREAD; | |
606d099c AC |
852 | pts_driver->init_termios.c_ispeed = 38400; |
853 | pts_driver->init_termios.c_ospeed = 38400; | |
1da177e4 | 854 | pts_driver->other = ptm_driver; |
99f1fe18 | 855 | tty_set_operations(pts_driver, &pty_unix98_ops); |
fe9cd962 | 856 | |
1da177e4 LT |
857 | if (tty_register_driver(ptm_driver)) |
858 | panic("Couldn't register Unix98 ptm driver"); | |
859 | if (tty_register_driver(pts_driver)) | |
860 | panic("Couldn't register Unix98 pts driver"); | |
861 | ||
d81ed103 AC |
862 | /* Now create the /dev/ptmx special device */ |
863 | tty_default_fops(&ptmx_fops); | |
864 | ptmx_fops.open = ptmx_open; | |
865 | ||
866 | cdev_init(&ptmx_cdev, &ptmx_fops); | |
867 | if (cdev_add(&ptmx_cdev, MKDEV(TTYAUX_MAJOR, 2), 1) || | |
868 | register_chrdev_region(MKDEV(TTYAUX_MAJOR, 2), 1, "/dev/ptmx") < 0) | |
82f8c35f | 869 | panic("Couldn't register /dev/ptmx driver"); |
d81ed103 | 870 | device_create(tty_class, NULL, MKDEV(TTYAUX_MAJOR, 2), NULL, "ptmx"); |
1da177e4 | 871 | } |
d81ed103 | 872 | |
1da177e4 LT |
873 | #else |
874 | static inline void unix98_pty_init(void) { } | |
875 | #endif | |
876 | ||
877 | static int __init pty_init(void) | |
878 | { | |
879 | legacy_pty_init(); | |
880 | unix98_pty_init(); | |
881 | return 0; | |
882 | } | |
7154988f | 883 | device_initcall(pty_init); |