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) { | |
9db276f8 | 266 | int extproc = (old_termios->c_lflag & EXTPROC) | L_EXTPROC(tty); |
dbfcd851 PH |
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 | |
55199ea3 PH |
386 | /* Opening the slave first has always returned -EIO */ |
387 | if (driver->subtype != PTY_TYPE_MASTER) | |
388 | return -EIO; | |
389 | ||
d03702a2 JS |
390 | ports[0] = kmalloc(sizeof **ports, GFP_KERNEL); |
391 | ports[1] = kmalloc(sizeof **ports, GFP_KERNEL); | |
6f9ea7ad | 392 | if (!ports[0] || !ports[1]) |
2c964a2f | 393 | goto err; |
bf970ee4 AC |
394 | if (!try_module_get(driver->other->owner)) { |
395 | /* This cannot in fact currently happen */ | |
2c964a2f | 396 | goto err; |
bf970ee4 | 397 | } |
2c964a2f RV |
398 | o_tty = alloc_tty_struct(driver->other, idx); |
399 | if (!o_tty) | |
400 | goto err_put_module; | |
bf970ee4 | 401 | |
2febdb63 | 402 | tty_set_lock_subclass(o_tty); |
d2b6f447 | 403 | lockdep_set_subclass(&o_tty->termios_rwsem, TTY_LOCK_SLAVE); |
2febdb63 | 404 | |
5d249bc6 JS |
405 | if (legacy) { |
406 | /* We always use new tty termios data so we can do this | |
407 | the easy way .. */ | |
a3123fd0 PH |
408 | tty_init_termios(tty); |
409 | tty_init_termios(o_tty); | |
5d249bc6 JS |
410 | |
411 | driver->other->ttys[idx] = o_tty; | |
412 | driver->ttys[idx] = tty; | |
413 | } else { | |
adc8d746 AC |
414 | memset(&tty->termios_locked, 0, sizeof(tty->termios_locked)); |
415 | tty->termios = driver->init_termios; | |
416 | memset(&o_tty->termios_locked, 0, sizeof(tty->termios_locked)); | |
417 | o_tty->termios = driver->other->init_termios; | |
5d249bc6 | 418 | } |
fe9cd962 | 419 | |
bf970ee4 AC |
420 | /* |
421 | * Everything allocated ... set up the o_tty structure. | |
422 | */ | |
bf970ee4 | 423 | tty_driver_kref_get(driver->other); |
bf970ee4 AC |
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]); | |
c81622ac PH |
429 | tty_buffer_set_limit(ports[0], 8192); |
430 | tty_buffer_set_limit(ports[1], 8192); | |
d03702a2 JS |
431 | o_tty->port = ports[0]; |
432 | tty->port = ports[1]; | |
967fab69 | 433 | o_tty->port->itty = o_tty; |
bf970ee4 | 434 | |
1d1d14da PH |
435 | tty_buffer_set_lock_subclass(o_tty->port); |
436 | ||
bf970ee4 AC |
437 | tty_driver_kref_get(driver); |
438 | tty->count++; | |
55199ea3 | 439 | o_tty->count++; |
bf970ee4 | 440 | return 0; |
a3123fd0 | 441 | |
2c964a2f | 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 | 491 | static int legacy_count = CONFIG_LEGACY_PTY_COUNT; |
7154988f PG |
492 | /* |
493 | * not really modular, but the easiest way to keep compat with existing | |
494 | * bootargs behaviour is to continue using module_param here. | |
495 | */ | |
dc8c8587 KS |
496 | module_param(legacy_count, int, 0); |
497 | ||
342a5971 LT |
498 | /* |
499 | * The master side of a pty can do TIOCSPTLCK and thus | |
500 | * has pty_bsd_ioctl. | |
501 | */ | |
502 | static const struct tty_operations master_pty_ops_bsd = { | |
503 | .install = pty_install, | |
3e8e88ca AC |
504 | .open = pty_open, |
505 | .close = pty_close, | |
506 | .write = pty_write, | |
507 | .write_room = pty_write_room, | |
508 | .flush_buffer = pty_flush_buffer, | |
509 | .chars_in_buffer = pty_chars_in_buffer, | |
510 | .unthrottle = pty_unthrottle, | |
3e8e88ca | 511 | .ioctl = pty_bsd_ioctl, |
d03702a2 | 512 | .cleanup = pty_cleanup, |
d155255a AC |
513 | .resize = pty_resize, |
514 | .remove = pty_remove | |
3e8e88ca AC |
515 | }; |
516 | ||
342a5971 LT |
517 | static const struct tty_operations slave_pty_ops_bsd = { |
518 | .install = pty_install, | |
519 | .open = pty_open, | |
520 | .close = pty_close, | |
521 | .write = pty_write, | |
522 | .write_room = pty_write_room, | |
523 | .flush_buffer = pty_flush_buffer, | |
524 | .chars_in_buffer = pty_chars_in_buffer, | |
525 | .unthrottle = pty_unthrottle, | |
526 | .set_termios = pty_set_termios, | |
d03702a2 | 527 | .cleanup = pty_cleanup, |
d155255a | 528 | .resize = pty_resize, |
01adc807 PH |
529 | .start = pty_start, |
530 | .stop = pty_stop, | |
d155255a | 531 | .remove = pty_remove |
342a5971 LT |
532 | }; |
533 | ||
1da177e4 LT |
534 | static void __init legacy_pty_init(void) |
535 | { | |
342a5971 LT |
536 | struct tty_driver *pty_driver, *pty_slave_driver; |
537 | ||
dc8c8587 KS |
538 | if (legacy_count <= 0) |
539 | return; | |
1da177e4 | 540 | |
21aca2fa JS |
541 | pty_driver = tty_alloc_driver(legacy_count, |
542 | TTY_DRIVER_RESET_TERMIOS | | |
543 | TTY_DRIVER_REAL_RAW | | |
544 | TTY_DRIVER_DYNAMIC_ALLOC); | |
c3a6344a | 545 | if (IS_ERR(pty_driver)) |
1da177e4 LT |
546 | panic("Couldn't allocate pty driver"); |
547 | ||
21aca2fa JS |
548 | pty_slave_driver = tty_alloc_driver(legacy_count, |
549 | TTY_DRIVER_RESET_TERMIOS | | |
550 | TTY_DRIVER_REAL_RAW | | |
551 | TTY_DRIVER_DYNAMIC_ALLOC); | |
c3a6344a | 552 | if (IS_ERR(pty_slave_driver)) |
1da177e4 LT |
553 | panic("Couldn't allocate pty slave driver"); |
554 | ||
1da177e4 LT |
555 | pty_driver->driver_name = "pty_master"; |
556 | pty_driver->name = "pty"; | |
1da177e4 LT |
557 | pty_driver->major = PTY_MASTER_MAJOR; |
558 | pty_driver->minor_start = 0; | |
559 | pty_driver->type = TTY_DRIVER_TYPE_PTY; | |
560 | pty_driver->subtype = PTY_TYPE_MASTER; | |
561 | pty_driver->init_termios = tty_std_termios; | |
562 | pty_driver->init_termios.c_iflag = 0; | |
563 | pty_driver->init_termios.c_oflag = 0; | |
564 | pty_driver->init_termios.c_cflag = B38400 | CS8 | CREAD; | |
565 | pty_driver->init_termios.c_lflag = 0; | |
606d099c AC |
566 | pty_driver->init_termios.c_ispeed = 38400; |
567 | pty_driver->init_termios.c_ospeed = 38400; | |
1da177e4 | 568 | pty_driver->other = pty_slave_driver; |
342a5971 | 569 | tty_set_operations(pty_driver, &master_pty_ops_bsd); |
1da177e4 | 570 | |
1da177e4 LT |
571 | pty_slave_driver->driver_name = "pty_slave"; |
572 | pty_slave_driver->name = "ttyp"; | |
1da177e4 LT |
573 | pty_slave_driver->major = PTY_SLAVE_MAJOR; |
574 | pty_slave_driver->minor_start = 0; | |
575 | pty_slave_driver->type = TTY_DRIVER_TYPE_PTY; | |
576 | pty_slave_driver->subtype = PTY_TYPE_SLAVE; | |
577 | pty_slave_driver->init_termios = tty_std_termios; | |
578 | pty_slave_driver->init_termios.c_cflag = B38400 | CS8 | CREAD; | |
606d099c AC |
579 | pty_slave_driver->init_termios.c_ispeed = 38400; |
580 | pty_slave_driver->init_termios.c_ospeed = 38400; | |
1da177e4 | 581 | pty_slave_driver->other = pty_driver; |
342a5971 | 582 | tty_set_operations(pty_slave_driver, &slave_pty_ops_bsd); |
1da177e4 LT |
583 | |
584 | if (tty_register_driver(pty_driver)) | |
585 | panic("Couldn't register pty driver"); | |
586 | if (tty_register_driver(pty_slave_driver)) | |
587 | panic("Couldn't register pty slave driver"); | |
588 | } | |
589 | #else | |
590 | static inline void legacy_pty_init(void) { } | |
591 | #endif | |
592 | ||
593 | /* Unix98 devices */ | |
594 | #ifdef CONFIG_UNIX98_PTYS | |
1da177e4 | 595 | |
d81ed103 AC |
596 | static struct cdev ptmx_cdev; |
597 | ||
6caa76b7 | 598 | static int pty_unix98_ioctl(struct tty_struct *tty, |
1da177e4 LT |
599 | unsigned int cmd, unsigned long arg) |
600 | { | |
601 | switch (cmd) { | |
602 | case TIOCSPTLCK: /* Set PT Lock (disallow slave open) */ | |
603 | return pty_set_lock(tty, (int __user *)arg); | |
84fd7bdf CG |
604 | case TIOCGPTLCK: /* Get PT Lock status */ |
605 | return pty_get_lock(tty, (int __user *)arg); | |
06026d91 CG |
606 | case TIOCPKT: /* Set PT packet mode */ |
607 | return pty_set_pktmode(tty, (int __user *)arg); | |
84fd7bdf CG |
608 | case TIOCGPKT: /* Get PT packet mode */ |
609 | return pty_get_pktmode(tty, (int __user *)arg); | |
1da177e4 LT |
610 | case TIOCGPTN: /* Get PT Number */ |
611 | return put_user(tty->index, (unsigned int __user *)arg); | |
26df6d13 | 612 | case TIOCSIG: /* Send signal to other side of pty */ |
613 | return pty_signal(tty, (int) arg); | |
1da177e4 LT |
614 | } |
615 | ||
616 | return -ENOIOCTLCMD; | |
617 | } | |
618 | ||
99f1fe18 AC |
619 | /** |
620 | * ptm_unix98_lookup - find a pty master | |
621 | * @driver: ptm driver | |
622 | * @idx: tty index | |
623 | * | |
624 | * Look up a pty master device. Called under the tty_mutex for now. | |
625 | * This provides our locking. | |
626 | */ | |
627 | ||
15f1a633 SB |
628 | static struct tty_struct *ptm_unix98_lookup(struct tty_driver *driver, |
629 | struct inode *ptm_inode, int idx) | |
99f1fe18 | 630 | { |
593a27c4 KK |
631 | /* Master must be open via /dev/ptmx */ |
632 | return ERR_PTR(-EIO); | |
99f1fe18 AC |
633 | } |
634 | ||
635 | /** | |
636 | * pts_unix98_lookup - find a pty slave | |
637 | * @driver: pts driver | |
638 | * @idx: tty index | |
639 | * | |
640 | * Look up a pty master device. Called under the tty_mutex for now. | |
d739e65b | 641 | * This provides our locking for the tty pointer. |
99f1fe18 AC |
642 | */ |
643 | ||
15f1a633 SB |
644 | static struct tty_struct *pts_unix98_lookup(struct tty_driver *driver, |
645 | struct inode *pts_inode, int idx) | |
99f1fe18 | 646 | { |
d739e65b AC |
647 | struct tty_struct *tty; |
648 | ||
649 | mutex_lock(&devpts_mutex); | |
8fcbaa2b | 650 | tty = devpts_get_priv(pts_inode); |
d739e65b | 651 | mutex_unlock(&devpts_mutex); |
99f1fe18 AC |
652 | /* Master must be open before slave */ |
653 | if (!tty) | |
654 | return ERR_PTR(-EIO); | |
655 | return tty; | |
656 | } | |
657 | ||
bf970ee4 | 658 | static int pty_unix98_install(struct tty_driver *driver, struct tty_struct *tty) |
8b0a88d5 | 659 | { |
5d249bc6 | 660 | return pty_common_install(driver, tty, false); |
8b0a88d5 AC |
661 | } |
662 | ||
f4b208eb | 663 | /* this is called once with whichever end is closed last */ |
c1e33af1 | 664 | static void pty_unix98_remove(struct tty_driver *driver, struct tty_struct *tty) |
f4b208eb | 665 | { |
2831c89f HK |
666 | struct inode *ptmx_inode; |
667 | ||
668 | if (tty->driver->subtype == PTY_TYPE_MASTER) | |
669 | ptmx_inode = tty->driver_data; | |
670 | else | |
671 | ptmx_inode = tty->link->driver_data; | |
672 | devpts_kill_index(ptmx_inode, tty->index); | |
1f55c718 | 673 | devpts_del_ref(ptmx_inode); |
f4b208eb JS |
674 | } |
675 | ||
feebed65 | 676 | static const struct tty_operations ptm_unix98_ops = { |
99f1fe18 | 677 | .lookup = ptm_unix98_lookup, |
bf970ee4 | 678 | .install = pty_unix98_install, |
7171604a | 679 | .remove = pty_unix98_remove, |
3e8e88ca AC |
680 | .open = pty_open, |
681 | .close = pty_close, | |
682 | .write = pty_write, | |
683 | .write_room = pty_write_room, | |
684 | .flush_buffer = pty_flush_buffer, | |
685 | .chars_in_buffer = pty_chars_in_buffer, | |
686 | .unthrottle = pty_unthrottle, | |
feebed65 | 687 | .ioctl = pty_unix98_ioctl, |
36b3c070 AC |
688 | .resize = pty_resize, |
689 | .cleanup = pty_cleanup | |
3e8e88ca AC |
690 | }; |
691 | ||
99f1fe18 AC |
692 | static const struct tty_operations pty_unix98_ops = { |
693 | .lookup = pts_unix98_lookup, | |
bf970ee4 | 694 | .install = pty_unix98_install, |
7171604a | 695 | .remove = pty_unix98_remove, |
99f1fe18 AC |
696 | .open = pty_open, |
697 | .close = pty_close, | |
698 | .write = pty_write, | |
699 | .write_room = pty_write_room, | |
700 | .flush_buffer = pty_flush_buffer, | |
701 | .chars_in_buffer = pty_chars_in_buffer, | |
702 | .unthrottle = pty_unthrottle, | |
703 | .set_termios = pty_set_termios, | |
01adc807 PH |
704 | .start = pty_start, |
705 | .stop = pty_stop, | |
d03702a2 | 706 | .cleanup = pty_cleanup, |
99f1fe18 | 707 | }; |
d81ed103 AC |
708 | |
709 | /** | |
710 | * ptmx_open - open a unix 98 pty master | |
711 | * @inode: inode of device file | |
712 | * @filp: file pointer to tty | |
713 | * | |
714 | * Allocate a unix98 pty master device from the ptmx driver. | |
715 | * | |
716 | * Locking: tty_mutex protects the init_dev work. tty->count should | |
b9f8033f | 717 | * protect the rest. |
d81ed103 AC |
718 | * allocated_ptys_lock handles the list of free pty numbers |
719 | */ | |
720 | ||
64ba3dc3 | 721 | static int ptmx_open(struct inode *inode, struct file *filp) |
d81ed103 AC |
722 | { |
723 | struct tty_struct *tty; | |
162b97cf | 724 | struct inode *slave_inode; |
d81ed103 AC |
725 | int retval; |
726 | int index; | |
727 | ||
728 | nonseekable_open(inode, filp); | |
729 | ||
b0b88565 LT |
730 | /* We refuse fsnotify events on ptmx, since it's a shared resource */ |
731 | filp->f_mode |= FMODE_NONOTIFY; | |
732 | ||
fa90e1c9 JS |
733 | retval = tty_alloc_file(filp); |
734 | if (retval) | |
735 | return retval; | |
736 | ||
d81ed103 | 737 | /* find a device that is not in use. */ |
89c8d91e | 738 | mutex_lock(&devpts_mutex); |
15f1a633 | 739 | index = devpts_new_index(inode); |
fa90e1c9 JS |
740 | if (index < 0) { |
741 | retval = index; | |
05fb79e4 | 742 | mutex_unlock(&devpts_mutex); |
fa90e1c9 JS |
743 | goto err_file; |
744 | } | |
d81ed103 | 745 | |
89c8d91e AC |
746 | mutex_unlock(&devpts_mutex); |
747 | ||
d81ed103 | 748 | mutex_lock(&tty_mutex); |
593a27c4 | 749 | tty = tty_init_dev(ptm_driver, index); |
d81ed103 | 750 | |
73ec06fc AC |
751 | if (IS_ERR(tty)) { |
752 | retval = PTR_ERR(tty); | |
d81ed103 | 753 | goto out; |
73ec06fc | 754 | } |
d81ed103 | 755 | |
89c8d91e AC |
756 | /* The tty returned here is locked so we can safely |
757 | drop the mutex */ | |
758 | mutex_unlock(&tty_mutex); | |
759 | ||
d81ed103 | 760 | set_bit(TTY_PTY_LOCK, &tty->flags); /* LOCK THE SLAVE */ |
7acf6cd8 | 761 | tty->driver_data = inode; |
ee2ffa0d | 762 | |
2831c89f HK |
763 | /* |
764 | * In the case where all references to ptmx inode are dropped and we | |
765 | * still have /dev/tty opened pointing to the master/slave pair (ptmx | |
766 | * is closed/released before /dev/tty), we must make sure that the inode | |
767 | * is still valid when we call the final pty_unix98_shutdown, thus we | |
1f55c718 HK |
768 | * hold an additional reference to the ptmx inode. For the same /dev/tty |
769 | * last close case, we also need to make sure the super_block isn't | |
770 | * destroyed (devpts instance unmounted), before /dev/tty is closed and | |
771 | * on its release devpts_kill_index is called. | |
2831c89f | 772 | */ |
1f55c718 | 773 | devpts_add_ref(inode); |
2831c89f | 774 | |
fa90e1c9 | 775 | tty_add_file(tty, filp); |
d81ed103 | 776 | |
f11afb61 JS |
777 | slave_inode = devpts_pty_new(inode, |
778 | MKDEV(UNIX98_PTY_SLAVE_MAJOR, index), index, | |
779 | tty->link); | |
162b97cf JS |
780 | if (IS_ERR(slave_inode)) { |
781 | retval = PTR_ERR(slave_inode); | |
1177c0ef | 782 | goto err_release; |
162b97cf | 783 | } |
7acf6cd8 | 784 | tty->link->driver_data = slave_inode; |
d81ed103 AC |
785 | |
786 | retval = ptm_driver->ops->open(tty, filp); | |
64ba3dc3 | 787 | if (retval) |
1177c0ef JS |
788 | goto err_release; |
789 | ||
d435cefe | 790 | tty_debug_hangup(tty, "opening (count=%d)\n", tty->count); |
d6847793 | 791 | |
89c8d91e | 792 | tty_unlock(tty); |
1177c0ef JS |
793 | return 0; |
794 | err_release: | |
89c8d91e | 795 | tty_unlock(tty); |
eeb89d91 | 796 | tty_release(inode, filp); |
d81ed103 AC |
797 | return retval; |
798 | out: | |
89c8d91e | 799 | mutex_unlock(&tty_mutex); |
d3bda529 | 800 | devpts_kill_index(inode, index); |
fa90e1c9 JS |
801 | err_file: |
802 | tty_free_file(filp); | |
64ba3dc3 | 803 | return retval; |
d81ed103 AC |
804 | } |
805 | ||
806 | static struct file_operations ptmx_fops; | |
807 | ||
1da177e4 LT |
808 | static void __init unix98_pty_init(void) |
809 | { | |
21aca2fa JS |
810 | ptm_driver = tty_alloc_driver(NR_UNIX98_PTY_MAX, |
811 | TTY_DRIVER_RESET_TERMIOS | | |
812 | TTY_DRIVER_REAL_RAW | | |
813 | TTY_DRIVER_DYNAMIC_DEV | | |
814 | TTY_DRIVER_DEVPTS_MEM | | |
815 | TTY_DRIVER_DYNAMIC_ALLOC); | |
c3a6344a | 816 | if (IS_ERR(ptm_driver)) |
1da177e4 | 817 | panic("Couldn't allocate Unix98 ptm driver"); |
21aca2fa JS |
818 | pts_driver = tty_alloc_driver(NR_UNIX98_PTY_MAX, |
819 | TTY_DRIVER_RESET_TERMIOS | | |
820 | TTY_DRIVER_REAL_RAW | | |
821 | TTY_DRIVER_DYNAMIC_DEV | | |
822 | TTY_DRIVER_DEVPTS_MEM | | |
823 | TTY_DRIVER_DYNAMIC_ALLOC); | |
c3a6344a | 824 | if (IS_ERR(pts_driver)) |
1da177e4 LT |
825 | panic("Couldn't allocate Unix98 pts driver"); |
826 | ||
1da177e4 LT |
827 | ptm_driver->driver_name = "pty_master"; |
828 | ptm_driver->name = "ptm"; | |
829 | ptm_driver->major = UNIX98_PTY_MASTER_MAJOR; | |
830 | ptm_driver->minor_start = 0; | |
831 | ptm_driver->type = TTY_DRIVER_TYPE_PTY; | |
832 | ptm_driver->subtype = PTY_TYPE_MASTER; | |
833 | ptm_driver->init_termios = tty_std_termios; | |
834 | ptm_driver->init_termios.c_iflag = 0; | |
835 | ptm_driver->init_termios.c_oflag = 0; | |
836 | ptm_driver->init_termios.c_cflag = B38400 | CS8 | CREAD; | |
837 | ptm_driver->init_termios.c_lflag = 0; | |
606d099c AC |
838 | ptm_driver->init_termios.c_ispeed = 38400; |
839 | ptm_driver->init_termios.c_ospeed = 38400; | |
1da177e4 | 840 | ptm_driver->other = pts_driver; |
feebed65 | 841 | tty_set_operations(ptm_driver, &ptm_unix98_ops); |
1da177e4 | 842 | |
1da177e4 LT |
843 | pts_driver->driver_name = "pty_slave"; |
844 | pts_driver->name = "pts"; | |
845 | pts_driver->major = UNIX98_PTY_SLAVE_MAJOR; | |
846 | pts_driver->minor_start = 0; | |
847 | pts_driver->type = TTY_DRIVER_TYPE_PTY; | |
848 | pts_driver->subtype = PTY_TYPE_SLAVE; | |
849 | pts_driver->init_termios = tty_std_termios; | |
850 | pts_driver->init_termios.c_cflag = B38400 | CS8 | CREAD; | |
606d099c AC |
851 | pts_driver->init_termios.c_ispeed = 38400; |
852 | pts_driver->init_termios.c_ospeed = 38400; | |
1da177e4 | 853 | pts_driver->other = ptm_driver; |
99f1fe18 | 854 | tty_set_operations(pts_driver, &pty_unix98_ops); |
fe9cd962 | 855 | |
1da177e4 LT |
856 | if (tty_register_driver(ptm_driver)) |
857 | panic("Couldn't register Unix98 ptm driver"); | |
858 | if (tty_register_driver(pts_driver)) | |
859 | panic("Couldn't register Unix98 pts driver"); | |
860 | ||
d81ed103 AC |
861 | /* Now create the /dev/ptmx special device */ |
862 | tty_default_fops(&ptmx_fops); | |
863 | ptmx_fops.open = ptmx_open; | |
864 | ||
865 | cdev_init(&ptmx_cdev, &ptmx_fops); | |
866 | if (cdev_add(&ptmx_cdev, MKDEV(TTYAUX_MAJOR, 2), 1) || | |
867 | register_chrdev_region(MKDEV(TTYAUX_MAJOR, 2), 1, "/dev/ptmx") < 0) | |
82f8c35f | 868 | panic("Couldn't register /dev/ptmx driver"); |
d81ed103 | 869 | device_create(tty_class, NULL, MKDEV(TTYAUX_MAJOR, 2), NULL, "ptmx"); |
1da177e4 | 870 | } |
d81ed103 | 871 | |
1da177e4 LT |
872 | #else |
873 | static inline void unix98_pty_init(void) { } | |
874 | #endif | |
875 | ||
876 | static int __init pty_init(void) | |
877 | { | |
878 | legacy_pty_init(); | |
879 | unix98_pty_init(); | |
880 | return 0; | |
881 | } | |
7154988f | 882 | device_initcall(pty_init); |