Commit | Line | Data |
---|---|---|
e3b3d0f5 | 1 | // SPDX-License-Identifier: GPL-2.0 |
1da177e4 | 2 | /* |
1da177e4 LT |
3 | * Copyright (C) 1991, 1992, 1993, 1994 Linus Torvalds |
4 | * | |
5 | * Modified by Fred N. van Kempen, 01/29/93, to add line disciplines | |
6 | * which can be dynamically activated and de-activated by the line | |
7 | * discipline handling modules (like SLIP). | |
8 | */ | |
9 | ||
10 | #include <linux/types.h> | |
11 | #include <linux/termios.h> | |
12 | #include <linux/errno.h> | |
174cd4b1 | 13 | #include <linux/sched/signal.h> |
1da177e4 LT |
14 | #include <linux/kernel.h> |
15 | #include <linux/major.h> | |
16 | #include <linux/tty.h> | |
17 | #include <linux/fcntl.h> | |
18 | #include <linux/string.h> | |
19 | #include <linux/mm.h> | |
20 | #include <linux/module.h> | |
21 | #include <linux/bitops.h> | |
5785c95b | 22 | #include <linux/mutex.h> |
8193c429 | 23 | #include <linux/compat.h> |
1da177e4 LT |
24 | |
25 | #include <asm/io.h> | |
7c0f6ba6 | 26 | #include <linux/uaccess.h> |
1da177e4 LT |
27 | |
28 | #undef TTY_DEBUG_WAIT_UNTIL_SENT | |
29 | ||
ff8339dc PH |
30 | #ifdef TTY_DEBUG_WAIT_UNTIL_SENT |
31 | # define tty_debug_wait_until_sent(tty, f, args...) tty_debug(tty, f, ##args) | |
32 | #else | |
33 | # define tty_debug_wait_until_sent(tty, f, args...) do {} while (0) | |
34 | #endif | |
35 | ||
1da177e4 LT |
36 | #undef DEBUG |
37 | ||
38 | /* | |
39 | * Internal flag options for termios setting behavior | |
40 | */ | |
41 | #define TERMIOS_FLUSH 1 | |
42 | #define TERMIOS_WAIT 2 | |
43 | #define TERMIOS_TERMIO 4 | |
edc6afc5 | 44 | #define TERMIOS_OLD 8 |
1da177e4 | 45 | |
af9b897e | 46 | |
d81ed103 AC |
47 | /** |
48 | * tty_chars_in_buffer - characters pending | |
49 | * @tty: terminal | |
50 | * | |
51 | * Return the number of bytes of data in the device private | |
52 | * output queue. If no private method is supplied there is assumed | |
53 | * to be no queue on the device. | |
54 | */ | |
55 | ||
f34d7a5b AC |
56 | int tty_chars_in_buffer(struct tty_struct *tty) |
57 | { | |
58 | if (tty->ops->chars_in_buffer) | |
59 | return tty->ops->chars_in_buffer(tty); | |
60 | else | |
61 | return 0; | |
62 | } | |
f34d7a5b AC |
63 | EXPORT_SYMBOL(tty_chars_in_buffer); |
64 | ||
d81ed103 AC |
65 | /** |
66 | * tty_write_room - write queue space | |
67 | * @tty: terminal | |
68 | * | |
69 | * Return the number of bytes that can be queued to this device | |
70 | * at the present time. The result should be treated as a guarantee | |
71 | * and the driver cannot offer a value it later shrinks by more than | |
72 | * the number of bytes written. If no method is provided 2K is always | |
73 | * returned and data may be lost as there will be no flow control. | |
74 | */ | |
75 | ||
f34d7a5b AC |
76 | int tty_write_room(struct tty_struct *tty) |
77 | { | |
78 | if (tty->ops->write_room) | |
79 | return tty->ops->write_room(tty); | |
80 | return 2048; | |
81 | } | |
f34d7a5b AC |
82 | EXPORT_SYMBOL(tty_write_room); |
83 | ||
d81ed103 AC |
84 | /** |
85 | * tty_driver_flush_buffer - discard internal buffer | |
86 | * @tty: terminal | |
87 | * | |
88 | * Discard the internal output buffer for this device. If no method | |
89 | * is provided then either the buffer cannot be hardware flushed or | |
90 | * there is no buffer driver side. | |
91 | */ | |
f34d7a5b AC |
92 | void tty_driver_flush_buffer(struct tty_struct *tty) |
93 | { | |
94 | if (tty->ops->flush_buffer) | |
95 | tty->ops->flush_buffer(tty); | |
96 | } | |
f34d7a5b AC |
97 | EXPORT_SYMBOL(tty_driver_flush_buffer); |
98 | ||
d81ed103 AC |
99 | /** |
100 | * tty_throttle - flow control | |
101 | * @tty: terminal | |
102 | * | |
103 | * Indicate that a tty should stop transmitting data down the stack. | |
6a1c0680 | 104 | * Takes the termios rwsem to protect against parallel throttle/unthrottle |
38db8979 AC |
105 | * and also to ensure the driver can consistently reference its own |
106 | * termios data at this point when implementing software flow control. | |
d81ed103 AC |
107 | */ |
108 | ||
39c2e60f AC |
109 | void tty_throttle(struct tty_struct *tty) |
110 | { | |
6a1c0680 | 111 | down_write(&tty->termios_rwsem); |
39c2e60f AC |
112 | /* check TTY_THROTTLED first so it indicates our state */ |
113 | if (!test_and_set_bit(TTY_THROTTLED, &tty->flags) && | |
114 | tty->ops->throttle) | |
115 | tty->ops->throttle(tty); | |
70bc1264 | 116 | tty->flow_change = 0; |
6a1c0680 | 117 | up_write(&tty->termios_rwsem); |
39c2e60f AC |
118 | } |
119 | EXPORT_SYMBOL(tty_throttle); | |
120 | ||
d81ed103 AC |
121 | /** |
122 | * tty_unthrottle - flow control | |
123 | * @tty: terminal | |
124 | * | |
125 | * Indicate that a tty may continue transmitting data down the stack. | |
6a1c0680 | 126 | * Takes the termios rwsem to protect against parallel throttle/unthrottle |
38db8979 AC |
127 | * and also to ensure the driver can consistently reference its own |
128 | * termios data at this point when implementing software flow control. | |
129 | * | |
130 | * Drivers should however remember that the stack can issue a throttle, | |
131 | * then change flow control method, then unthrottle. | |
d81ed103 AC |
132 | */ |
133 | ||
39c2e60f AC |
134 | void tty_unthrottle(struct tty_struct *tty) |
135 | { | |
6a1c0680 | 136 | down_write(&tty->termios_rwsem); |
39c2e60f AC |
137 | if (test_and_clear_bit(TTY_THROTTLED, &tty->flags) && |
138 | tty->ops->unthrottle) | |
139 | tty->ops->unthrottle(tty); | |
70bc1264 | 140 | tty->flow_change = 0; |
6a1c0680 | 141 | up_write(&tty->termios_rwsem); |
39c2e60f AC |
142 | } |
143 | EXPORT_SYMBOL(tty_unthrottle); | |
f34d7a5b | 144 | |
70bc1264 PH |
145 | /** |
146 | * tty_throttle_safe - flow control | |
147 | * @tty: terminal | |
148 | * | |
149 | * Similar to tty_throttle() but will only attempt throttle | |
150 | * if tty->flow_change is TTY_THROTTLE_SAFE. Prevents an accidental | |
151 | * throttle due to race conditions when throttling is conditional | |
152 | * on factors evaluated prior to throttling. | |
153 | * | |
154 | * Returns 0 if tty is throttled (or was already throttled) | |
155 | */ | |
156 | ||
157 | int tty_throttle_safe(struct tty_struct *tty) | |
158 | { | |
159 | int ret = 0; | |
160 | ||
d8c1f929 | 161 | mutex_lock(&tty->throttle_mutex); |
97ef38b8 | 162 | if (!tty_throttled(tty)) { |
70bc1264 PH |
163 | if (tty->flow_change != TTY_THROTTLE_SAFE) |
164 | ret = 1; | |
165 | else { | |
579a00a5 | 166 | set_bit(TTY_THROTTLED, &tty->flags); |
70bc1264 PH |
167 | if (tty->ops->throttle) |
168 | tty->ops->throttle(tty); | |
169 | } | |
170 | } | |
d8c1f929 | 171 | mutex_unlock(&tty->throttle_mutex); |
70bc1264 PH |
172 | |
173 | return ret; | |
174 | } | |
175 | ||
176 | /** | |
177 | * tty_unthrottle_safe - flow control | |
178 | * @tty: terminal | |
179 | * | |
180 | * Similar to tty_unthrottle() but will only attempt unthrottle | |
181 | * if tty->flow_change is TTY_UNTHROTTLE_SAFE. Prevents an accidental | |
182 | * unthrottle due to race conditions when unthrottling is conditional | |
183 | * on factors evaluated prior to unthrottling. | |
184 | * | |
185 | * Returns 0 if tty is unthrottled (or was already unthrottled) | |
186 | */ | |
187 | ||
188 | int tty_unthrottle_safe(struct tty_struct *tty) | |
189 | { | |
190 | int ret = 0; | |
191 | ||
d8c1f929 | 192 | mutex_lock(&tty->throttle_mutex); |
97ef38b8 | 193 | if (tty_throttled(tty)) { |
70bc1264 PH |
194 | if (tty->flow_change != TTY_UNTHROTTLE_SAFE) |
195 | ret = 1; | |
196 | else { | |
579a00a5 | 197 | clear_bit(TTY_THROTTLED, &tty->flags); |
70bc1264 PH |
198 | if (tty->ops->unthrottle) |
199 | tty->ops->unthrottle(tty); | |
200 | } | |
201 | } | |
d8c1f929 | 202 | mutex_unlock(&tty->throttle_mutex); |
70bc1264 PH |
203 | |
204 | return ret; | |
205 | } | |
206 | ||
af9b897e AC |
207 | /** |
208 | * tty_wait_until_sent - wait for I/O to finish | |
209 | * @tty: tty we are waiting for | |
210 | * @timeout: how long we will wait | |
211 | * | |
212 | * Wait for characters pending in a tty driver to hit the wire, or | |
213 | * for a timeout to occur (eg due to flow control) | |
214 | * | |
215 | * Locking: none | |
216 | */ | |
217 | ||
355d95a1 | 218 | void tty_wait_until_sent(struct tty_struct *tty, long timeout) |
1da177e4 | 219 | { |
d435cefe | 220 | tty_debug_wait_until_sent(tty, "wait until sent, timeout=%ld\n", timeout); |
ff8339dc | 221 | |
1da177e4 LT |
222 | if (!timeout) |
223 | timeout = MAX_SCHEDULE_TIMEOUT; | |
79fbf4a5 | 224 | |
c37bc682 JH |
225 | timeout = wait_event_interruptible_timeout(tty->write_wait, |
226 | !tty_chars_in_buffer(tty), timeout); | |
227 | if (timeout <= 0) | |
79fbf4a5 | 228 | return; |
79fbf4a5 JH |
229 | |
230 | if (timeout == MAX_SCHEDULE_TIMEOUT) | |
231 | timeout = 0; | |
232 | ||
233 | if (tty->ops->wait_until_sent) | |
234 | tty->ops->wait_until_sent(tty, timeout); | |
1da177e4 | 235 | } |
1da177e4 LT |
236 | EXPORT_SYMBOL(tty_wait_until_sent); |
237 | ||
d81ed103 AC |
238 | |
239 | /* | |
240 | * Termios Helper Methods | |
241 | */ | |
242 | ||
d97ba9cd | 243 | static void unset_locked_termios(struct tty_struct *tty, struct ktermios *old) |
1da177e4 | 244 | { |
d97ba9cd PH |
245 | struct ktermios *termios = &tty->termios; |
246 | struct ktermios *locked = &tty->termios_locked; | |
1da177e4 | 247 | int i; |
355d95a1 AC |
248 | |
249 | #define NOSET_MASK(x, y, z) (x = ((x) & ~(z)) | ((y) & (z))) | |
1da177e4 | 250 | |
1da177e4 LT |
251 | NOSET_MASK(termios->c_iflag, old->c_iflag, locked->c_iflag); |
252 | NOSET_MASK(termios->c_oflag, old->c_oflag, locked->c_oflag); | |
253 | NOSET_MASK(termios->c_cflag, old->c_cflag, locked->c_cflag); | |
254 | NOSET_MASK(termios->c_lflag, old->c_lflag, locked->c_lflag); | |
255 | termios->c_line = locked->c_line ? old->c_line : termios->c_line; | |
355d95a1 | 256 | for (i = 0; i < NCCS; i++) |
1da177e4 LT |
257 | termios->c_cc[i] = locked->c_cc[i] ? |
258 | old->c_cc[i] : termios->c_cc[i]; | |
edc6afc5 | 259 | /* FIXME: What should we do for i/ospeed */ |
1da177e4 LT |
260 | } |
261 | ||
5f519d72 AC |
262 | /** |
263 | * tty_termios_copy_hw - copy hardware settings | |
264 | * @new: New termios | |
265 | * @old: Old termios | |
266 | * | |
25985edc | 267 | * Propagate the hardware specific terminal setting bits from |
5f519d72 AC |
268 | * the old termios structure to the new one. This is used in cases |
269 | * where the hardware does not support reconfiguration or as a helper | |
270 | * in some cases where only minimal reconfiguration is supported | |
271 | */ | |
272 | ||
273 | void tty_termios_copy_hw(struct ktermios *new, struct ktermios *old) | |
274 | { | |
275 | /* The bits a dumb device handles in software. Smart devices need | |
276 | to always provide a set_termios method */ | |
277 | new->c_cflag &= HUPCL | CREAD | CLOCAL; | |
278 | new->c_cflag |= old->c_cflag & ~(HUPCL | CREAD | CLOCAL); | |
279 | new->c_ispeed = old->c_ispeed; | |
280 | new->c_ospeed = old->c_ospeed; | |
281 | } | |
5f519d72 AC |
282 | EXPORT_SYMBOL(tty_termios_copy_hw); |
283 | ||
bf5e5834 AC |
284 | /** |
285 | * tty_termios_hw_change - check for setting change | |
286 | * @a: termios | |
287 | * @b: termios to compare | |
288 | * | |
289 | * Check if any of the bits that affect a dumb device have changed | |
290 | * between the two termios structures, or a speed change is needed. | |
291 | */ | |
292 | ||
7b0c6b38 | 293 | int tty_termios_hw_change(const struct ktermios *a, const struct ktermios *b) |
bf5e5834 AC |
294 | { |
295 | if (a->c_ispeed != b->c_ispeed || a->c_ospeed != b->c_ospeed) | |
296 | return 1; | |
297 | if ((a->c_cflag ^ b->c_cflag) & ~(HUPCL | CREAD | CLOCAL)) | |
298 | return 1; | |
299 | return 0; | |
300 | } | |
301 | EXPORT_SYMBOL(tty_termios_hw_change); | |
302 | ||
af9b897e | 303 | /** |
8d075b19 | 304 | * tty_set_termios - update termios values |
af9b897e AC |
305 | * @tty: tty to update |
306 | * @new_termios: desired new value | |
307 | * | |
dbfcd851 | 308 | * Perform updates to the termios values set on this terminal. |
6460fbbf PH |
309 | * A master pty's termios should never be set. |
310 | * | |
6a1c0680 | 311 | * Locking: termios_rwsem |
af9b897e AC |
312 | */ |
313 | ||
b00f5c2d | 314 | int tty_set_termios(struct tty_struct *tty, struct ktermios *new_termios) |
1da177e4 | 315 | { |
978e595f | 316 | struct ktermios old_termios; |
1da177e4 | 317 | struct tty_ldisc *ld; |
355d95a1 | 318 | |
6460fbbf PH |
319 | WARN_ON(tty->driver->type == TTY_DRIVER_TYPE_PTY && |
320 | tty->driver->subtype == PTY_TYPE_MASTER); | |
1da177e4 LT |
321 | /* |
322 | * Perform the actual termios internal changes under lock. | |
323 | */ | |
355d95a1 | 324 | |
1da177e4 LT |
325 | |
326 | /* FIXME: we need to decide on some locking/ordering semantics | |
327 | for the set_termios notification eventually */ | |
6a1c0680 | 328 | down_write(&tty->termios_rwsem); |
adc8d746 AC |
329 | old_termios = tty->termios; |
330 | tty->termios = *new_termios; | |
d97ba9cd | 331 | unset_locked_termios(tty, &old_termios); |
1da177e4 | 332 | |
f34d7a5b | 333 | if (tty->ops->set_termios) |
c961bfb1 | 334 | tty->ops->set_termios(tty, &old_termios); |
5f519d72 | 335 | else |
adc8d746 | 336 | tty_termios_copy_hw(&tty->termios, &old_termios); |
1da177e4 LT |
337 | |
338 | ld = tty_ldisc_ref(tty); | |
339 | if (ld != NULL) { | |
a352def2 | 340 | if (ld->ops->set_termios) |
c961bfb1 | 341 | ld->ops->set_termios(tty, &old_termios); |
1da177e4 LT |
342 | tty_ldisc_deref(ld); |
343 | } | |
6a1c0680 | 344 | up_write(&tty->termios_rwsem); |
8d075b19 | 345 | return 0; |
1da177e4 | 346 | } |
b00f5c2d | 347 | EXPORT_SYMBOL_GPL(tty_set_termios); |
1da177e4 | 348 | |
af9b897e AC |
349 | /** |
350 | * set_termios - set termios values for a tty | |
351 | * @tty: terminal device | |
352 | * @arg: user data | |
353 | * @opt: option information | |
354 | * | |
3a4fa0a2 | 355 | * Helper function to prepare termios data and run necessary other |
8d075b19 | 356 | * functions before using tty_set_termios to do the actual changes. |
af9b897e AC |
357 | * |
358 | * Locking: | |
6a1c0680 | 359 | * Called functions take ldisc and termios_rwsem locks |
af9b897e AC |
360 | */ |
361 | ||
355d95a1 | 362 | static int set_termios(struct tty_struct *tty, void __user *arg, int opt) |
1da177e4 | 363 | { |
edc6afc5 | 364 | struct ktermios tmp_termios; |
1da177e4 LT |
365 | struct tty_ldisc *ld; |
366 | int retval = tty_check_change(tty); | |
367 | ||
368 | if (retval) | |
369 | return retval; | |
370 | ||
6a1c0680 | 371 | down_read(&tty->termios_rwsem); |
adc8d746 | 372 | tmp_termios = tty->termios; |
6a1c0680 | 373 | up_read(&tty->termios_rwsem); |
64bb6c5e | 374 | |
1da177e4 | 375 | if (opt & TERMIOS_TERMIO) { |
1da177e4 LT |
376 | if (user_termio_to_kernel_termios(&tmp_termios, |
377 | (struct termio __user *)arg)) | |
378 | return -EFAULT; | |
edc6afc5 AC |
379 | #ifdef TCGETS2 |
380 | } else if (opt & TERMIOS_OLD) { | |
edc6afc5 | 381 | if (user_termios_to_kernel_termios_1(&tmp_termios, |
64bb6c5e | 382 | (struct termios __user *)arg)) |
edc6afc5 | 383 | return -EFAULT; |
1da177e4 LT |
384 | } else { |
385 | if (user_termios_to_kernel_termios(&tmp_termios, | |
64bb6c5e | 386 | (struct termios2 __user *)arg)) |
1da177e4 LT |
387 | return -EFAULT; |
388 | } | |
64bb6c5e AC |
389 | #else |
390 | } else if (user_termios_to_kernel_termios(&tmp_termios, | |
391 | (struct termios __user *)arg)) | |
392 | return -EFAULT; | |
393 | #endif | |
1da177e4 | 394 | |
355d95a1 AC |
395 | /* If old style Bfoo values are used then load c_ispeed/c_ospeed |
396 | * with the real speed so its unconditionally usable */ | |
edc6afc5 AC |
397 | tmp_termios.c_ispeed = tty_termios_input_baud_rate(&tmp_termios); |
398 | tmp_termios.c_ospeed = tty_termios_baud_rate(&tmp_termios); | |
399 | ||
1da177e4 | 400 | ld = tty_ldisc_ref(tty); |
355d95a1 | 401 | |
1da177e4 | 402 | if (ld != NULL) { |
a352def2 AC |
403 | if ((opt & TERMIOS_FLUSH) && ld->ops->flush_buffer) |
404 | ld->ops->flush_buffer(tty); | |
1da177e4 LT |
405 | tty_ldisc_deref(ld); |
406 | } | |
355d95a1 | 407 | |
1da177e4 LT |
408 | if (opt & TERMIOS_WAIT) { |
409 | tty_wait_until_sent(tty, 0); | |
410 | if (signal_pending(current)) | |
183d95cd | 411 | return -ERESTARTSYS; |
1da177e4 LT |
412 | } |
413 | ||
8d075b19 | 414 | tty_set_termios(tty, &tmp_termios); |
5f519d72 AC |
415 | |
416 | /* FIXME: Arguably if tmp_termios == tty->termios AND the | |
417 | actual requested termios was not tmp_termios then we may | |
418 | want to return an error as no user requested change has | |
419 | succeeded */ | |
1da177e4 LT |
420 | return 0; |
421 | } | |
422 | ||
26a2e20f AC |
423 | static void copy_termios(struct tty_struct *tty, struct ktermios *kterm) |
424 | { | |
6a1c0680 | 425 | down_read(&tty->termios_rwsem); |
adc8d746 | 426 | *kterm = tty->termios; |
6a1c0680 | 427 | up_read(&tty->termios_rwsem); |
26a2e20f AC |
428 | } |
429 | ||
430 | static void copy_termios_locked(struct tty_struct *tty, struct ktermios *kterm) | |
431 | { | |
6a1c0680 | 432 | down_read(&tty->termios_rwsem); |
adc8d746 | 433 | *kterm = tty->termios_locked; |
6a1c0680 | 434 | up_read(&tty->termios_rwsem); |
26a2e20f AC |
435 | } |
436 | ||
355d95a1 | 437 | static int get_termio(struct tty_struct *tty, struct termio __user *termio) |
1da177e4 | 438 | { |
26a2e20f AC |
439 | struct ktermios kterm; |
440 | copy_termios(tty, &kterm); | |
441 | if (kernel_termios_to_user_termio(termio, &kterm)) | |
1da177e4 LT |
442 | return -EFAULT; |
443 | return 0; | |
444 | } | |
445 | ||
1d65b4a0 AC |
446 | |
447 | #ifdef TCGETX | |
448 | ||
449 | /** | |
450 | * set_termiox - set termiox fields if possible | |
451 | * @tty: terminal | |
452 | * @arg: termiox structure from user | |
453 | * @opt: option flags for ioctl type | |
454 | * | |
455 | * Implement the device calling points for the SYS5 termiox ioctl | |
456 | * interface in Linux | |
457 | */ | |
458 | ||
459 | static int set_termiox(struct tty_struct *tty, void __user *arg, int opt) | |
460 | { | |
461 | struct termiox tnew; | |
462 | struct tty_ldisc *ld; | |
463 | ||
464 | if (tty->termiox == NULL) | |
465 | return -EINVAL; | |
466 | if (copy_from_user(&tnew, arg, sizeof(struct termiox))) | |
467 | return -EFAULT; | |
468 | ||
469 | ld = tty_ldisc_ref(tty); | |
470 | if (ld != NULL) { | |
471 | if ((opt & TERMIOS_FLUSH) && ld->ops->flush_buffer) | |
472 | ld->ops->flush_buffer(tty); | |
473 | tty_ldisc_deref(ld); | |
474 | } | |
475 | if (opt & TERMIOS_WAIT) { | |
476 | tty_wait_until_sent(tty, 0); | |
477 | if (signal_pending(current)) | |
183d95cd | 478 | return -ERESTARTSYS; |
1d65b4a0 AC |
479 | } |
480 | ||
6a1c0680 | 481 | down_write(&tty->termios_rwsem); |
1d65b4a0 AC |
482 | if (tty->ops->set_termiox) |
483 | tty->ops->set_termiox(tty, &tnew); | |
6a1c0680 | 484 | up_write(&tty->termios_rwsem); |
1d65b4a0 AC |
485 | return 0; |
486 | } | |
487 | ||
488 | #endif | |
489 | ||
1da177e4 LT |
490 | |
491 | #ifdef TIOCGETP | |
492 | /* | |
493 | * These are deprecated, but there is limited support.. | |
494 | * | |
495 | * The "sg_flags" translation is a joke.. | |
496 | */ | |
355d95a1 | 497 | static int get_sgflags(struct tty_struct *tty) |
1da177e4 LT |
498 | { |
499 | int flags = 0; | |
500 | ||
9db276f8 PH |
501 | if (!L_ICANON(tty)) { |
502 | if (L_ISIG(tty)) | |
1da177e4 LT |
503 | flags |= 0x02; /* cbreak */ |
504 | else | |
505 | flags |= 0x20; /* raw */ | |
506 | } | |
9db276f8 | 507 | if (L_ECHO(tty)) |
1da177e4 | 508 | flags |= 0x08; /* echo */ |
9db276f8 PH |
509 | if (O_OPOST(tty)) |
510 | if (O_ONLCR(tty)) | |
1da177e4 LT |
511 | flags |= 0x10; /* crmod */ |
512 | return flags; | |
513 | } | |
514 | ||
355d95a1 | 515 | static int get_sgttyb(struct tty_struct *tty, struct sgttyb __user *sgttyb) |
1da177e4 LT |
516 | { |
517 | struct sgttyb tmp; | |
518 | ||
6a1c0680 | 519 | down_read(&tty->termios_rwsem); |
adc8d746 AC |
520 | tmp.sg_ispeed = tty->termios.c_ispeed; |
521 | tmp.sg_ospeed = tty->termios.c_ospeed; | |
522 | tmp.sg_erase = tty->termios.c_cc[VERASE]; | |
523 | tmp.sg_kill = tty->termios.c_cc[VKILL]; | |
1da177e4 | 524 | tmp.sg_flags = get_sgflags(tty); |
6a1c0680 | 525 | up_read(&tty->termios_rwsem); |
355d95a1 | 526 | |
1da177e4 LT |
527 | return copy_to_user(sgttyb, &tmp, sizeof(tmp)) ? -EFAULT : 0; |
528 | } | |
529 | ||
355d95a1 | 530 | static void set_sgflags(struct ktermios *termios, int flags) |
1da177e4 | 531 | { |
9833facf AC |
532 | termios->c_iflag = ICRNL | IXON; |
533 | termios->c_oflag = 0; | |
534 | termios->c_lflag = ISIG | ICANON; | |
1da177e4 | 535 | if (flags & 0x02) { /* cbreak */ |
9833facf AC |
536 | termios->c_iflag = 0; |
537 | termios->c_lflag &= ~ICANON; | |
1da177e4 LT |
538 | } |
539 | if (flags & 0x08) { /* echo */ | |
9833facf | 540 | termios->c_lflag |= ECHO | ECHOE | ECHOK | |
1da177e4 LT |
541 | ECHOCTL | ECHOKE | IEXTEN; |
542 | } | |
543 | if (flags & 0x10) { /* crmod */ | |
9833facf | 544 | termios->c_oflag |= OPOST | ONLCR; |
1da177e4 LT |
545 | } |
546 | if (flags & 0x20) { /* raw */ | |
9833facf AC |
547 | termios->c_iflag = 0; |
548 | termios->c_lflag &= ~(ISIG | ICANON); | |
1da177e4 | 549 | } |
9833facf AC |
550 | if (!(termios->c_lflag & ICANON)) { |
551 | termios->c_cc[VMIN] = 1; | |
552 | termios->c_cc[VTIME] = 0; | |
1da177e4 LT |
553 | } |
554 | } | |
555 | ||
af9b897e AC |
556 | /** |
557 | * set_sgttyb - set legacy terminal values | |
558 | * @tty: tty structure | |
559 | * @sgttyb: pointer to old style terminal structure | |
560 | * | |
561 | * Updates a terminal from the legacy BSD style terminal information | |
562 | * structure. | |
563 | * | |
6a1c0680 | 564 | * Locking: termios_rwsem |
af9b897e AC |
565 | */ |
566 | ||
355d95a1 | 567 | static int set_sgttyb(struct tty_struct *tty, struct sgttyb __user *sgttyb) |
1da177e4 LT |
568 | { |
569 | int retval; | |
570 | struct sgttyb tmp; | |
edc6afc5 | 571 | struct ktermios termios; |
1da177e4 LT |
572 | |
573 | retval = tty_check_change(tty); | |
574 | if (retval) | |
575 | return retval; | |
355d95a1 | 576 | |
1da177e4 LT |
577 | if (copy_from_user(&tmp, sgttyb, sizeof(tmp))) |
578 | return -EFAULT; | |
579 | ||
6a1c0680 | 580 | down_write(&tty->termios_rwsem); |
adc8d746 | 581 | termios = tty->termios; |
1da177e4 LT |
582 | termios.c_cc[VERASE] = tmp.sg_erase; |
583 | termios.c_cc[VKILL] = tmp.sg_kill; | |
584 | set_sgflags(&termios, tmp.sg_flags); | |
edc6afc5 AC |
585 | /* Try and encode into Bfoo format */ |
586 | #ifdef BOTHER | |
355d95a1 AC |
587 | tty_termios_encode_baud_rate(&termios, termios.c_ispeed, |
588 | termios.c_ospeed); | |
edc6afc5 | 589 | #endif |
6a1c0680 | 590 | up_write(&tty->termios_rwsem); |
8d075b19 | 591 | tty_set_termios(tty, &termios); |
1da177e4 LT |
592 | return 0; |
593 | } | |
594 | #endif | |
595 | ||
596 | #ifdef TIOCGETC | |
355d95a1 | 597 | static int get_tchars(struct tty_struct *tty, struct tchars __user *tchars) |
1da177e4 LT |
598 | { |
599 | struct tchars tmp; | |
600 | ||
6a1c0680 | 601 | down_read(&tty->termios_rwsem); |
adc8d746 AC |
602 | tmp.t_intrc = tty->termios.c_cc[VINTR]; |
603 | tmp.t_quitc = tty->termios.c_cc[VQUIT]; | |
604 | tmp.t_startc = tty->termios.c_cc[VSTART]; | |
605 | tmp.t_stopc = tty->termios.c_cc[VSTOP]; | |
606 | tmp.t_eofc = tty->termios.c_cc[VEOF]; | |
607 | tmp.t_brkc = tty->termios.c_cc[VEOL2]; /* what is brkc anyway? */ | |
6a1c0680 | 608 | up_read(&tty->termios_rwsem); |
1da177e4 LT |
609 | return copy_to_user(tchars, &tmp, sizeof(tmp)) ? -EFAULT : 0; |
610 | } | |
611 | ||
355d95a1 | 612 | static int set_tchars(struct tty_struct *tty, struct tchars __user *tchars) |
1da177e4 LT |
613 | { |
614 | struct tchars tmp; | |
615 | ||
616 | if (copy_from_user(&tmp, tchars, sizeof(tmp))) | |
617 | return -EFAULT; | |
6a1c0680 | 618 | down_write(&tty->termios_rwsem); |
adc8d746 AC |
619 | tty->termios.c_cc[VINTR] = tmp.t_intrc; |
620 | tty->termios.c_cc[VQUIT] = tmp.t_quitc; | |
621 | tty->termios.c_cc[VSTART] = tmp.t_startc; | |
622 | tty->termios.c_cc[VSTOP] = tmp.t_stopc; | |
623 | tty->termios.c_cc[VEOF] = tmp.t_eofc; | |
624 | tty->termios.c_cc[VEOL2] = tmp.t_brkc; /* what is brkc anyway? */ | |
6a1c0680 | 625 | up_write(&tty->termios_rwsem); |
1da177e4 LT |
626 | return 0; |
627 | } | |
628 | #endif | |
629 | ||
630 | #ifdef TIOCGLTC | |
355d95a1 | 631 | static int get_ltchars(struct tty_struct *tty, struct ltchars __user *ltchars) |
1da177e4 LT |
632 | { |
633 | struct ltchars tmp; | |
634 | ||
6a1c0680 | 635 | down_read(&tty->termios_rwsem); |
adc8d746 | 636 | tmp.t_suspc = tty->termios.c_cc[VSUSP]; |
355d95a1 | 637 | /* what is dsuspc anyway? */ |
adc8d746 AC |
638 | tmp.t_dsuspc = tty->termios.c_cc[VSUSP]; |
639 | tmp.t_rprntc = tty->termios.c_cc[VREPRINT]; | |
355d95a1 | 640 | /* what is flushc anyway? */ |
adc8d746 AC |
641 | tmp.t_flushc = tty->termios.c_cc[VEOL2]; |
642 | tmp.t_werasc = tty->termios.c_cc[VWERASE]; | |
643 | tmp.t_lnextc = tty->termios.c_cc[VLNEXT]; | |
6a1c0680 | 644 | up_read(&tty->termios_rwsem); |
1da177e4 LT |
645 | return copy_to_user(ltchars, &tmp, sizeof(tmp)) ? -EFAULT : 0; |
646 | } | |
647 | ||
355d95a1 | 648 | static int set_ltchars(struct tty_struct *tty, struct ltchars __user *ltchars) |
1da177e4 LT |
649 | { |
650 | struct ltchars tmp; | |
651 | ||
652 | if (copy_from_user(&tmp, ltchars, sizeof(tmp))) | |
653 | return -EFAULT; | |
654 | ||
6a1c0680 | 655 | down_write(&tty->termios_rwsem); |
adc8d746 | 656 | tty->termios.c_cc[VSUSP] = tmp.t_suspc; |
355d95a1 | 657 | /* what is dsuspc anyway? */ |
adc8d746 AC |
658 | tty->termios.c_cc[VEOL2] = tmp.t_dsuspc; |
659 | tty->termios.c_cc[VREPRINT] = tmp.t_rprntc; | |
355d95a1 | 660 | /* what is flushc anyway? */ |
adc8d746 AC |
661 | tty->termios.c_cc[VEOL2] = tmp.t_flushc; |
662 | tty->termios.c_cc[VWERASE] = tmp.t_werasc; | |
663 | tty->termios.c_cc[VLNEXT] = tmp.t_lnextc; | |
6a1c0680 | 664 | up_write(&tty->termios_rwsem); |
1da177e4 LT |
665 | return 0; |
666 | } | |
667 | #endif | |
668 | ||
1c2630cc AC |
669 | /** |
670 | * tty_change_softcar - carrier change ioctl helper | |
671 | * @tty: tty to update | |
672 | * @arg: enable/disable CLOCAL | |
673 | * | |
674 | * Perform a change to the CLOCAL state and call into the driver | |
6a1c0680 | 675 | * layer to make it visible. All done with the termios rwsem |
1c2630cc AC |
676 | */ |
677 | ||
678 | static int tty_change_softcar(struct tty_struct *tty, int arg) | |
679 | { | |
680 | int ret = 0; | |
681 | int bit = arg ? CLOCAL : 0; | |
f34d7a5b | 682 | struct ktermios old; |
1c2630cc | 683 | |
6a1c0680 | 684 | down_write(&tty->termios_rwsem); |
adc8d746 AC |
685 | old = tty->termios; |
686 | tty->termios.c_cflag &= ~CLOCAL; | |
687 | tty->termios.c_cflag |= bit; | |
f34d7a5b AC |
688 | if (tty->ops->set_termios) |
689 | tty->ops->set_termios(tty, &old); | |
9db276f8 | 690 | if (C_CLOCAL(tty) != bit) |
1c2630cc | 691 | ret = -EINVAL; |
6a1c0680 | 692 | up_write(&tty->termios_rwsem); |
1c2630cc AC |
693 | return ret; |
694 | } | |
695 | ||
0fc00e24 AC |
696 | /** |
697 | * tty_mode_ioctl - mode related ioctls | |
698 | * @tty: tty for the ioctl | |
699 | * @file: file pointer for the tty | |
700 | * @cmd: command | |
701 | * @arg: ioctl argument | |
702 | * | |
703 | * Perform non line discipline specific mode control ioctls. This | |
704 | * is designed to be called by line disciplines to ensure they provide | |
705 | * consistent mode setting. | |
706 | */ | |
707 | ||
355d95a1 | 708 | int tty_mode_ioctl(struct tty_struct *tty, struct file *file, |
0fc00e24 | 709 | unsigned int cmd, unsigned long arg) |
1da177e4 | 710 | { |
355d95a1 | 711 | struct tty_struct *real_tty; |
1da177e4 | 712 | void __user *p = (void __user *)arg; |
8f520021 | 713 | int ret = 0; |
26a2e20f | 714 | struct ktermios kterm; |
1da177e4 | 715 | |
8d075b19 AC |
716 | BUG_ON(file == NULL); |
717 | ||
1da177e4 LT |
718 | if (tty->driver->type == TTY_DRIVER_TYPE_PTY && |
719 | tty->driver->subtype == PTY_TYPE_MASTER) | |
720 | real_tty = tty->link; | |
721 | else | |
722 | real_tty = tty; | |
723 | ||
724 | switch (cmd) { | |
725 | #ifdef TIOCGETP | |
355d95a1 AC |
726 | case TIOCGETP: |
727 | return get_sgttyb(real_tty, (struct sgttyb __user *) arg); | |
728 | case TIOCSETP: | |
729 | case TIOCSETN: | |
730 | return set_sgttyb(real_tty, (struct sgttyb __user *) arg); | |
1da177e4 LT |
731 | #endif |
732 | #ifdef TIOCGETC | |
355d95a1 AC |
733 | case TIOCGETC: |
734 | return get_tchars(real_tty, p); | |
735 | case TIOCSETC: | |
736 | return set_tchars(real_tty, p); | |
1da177e4 LT |
737 | #endif |
738 | #ifdef TIOCGLTC | |
355d95a1 AC |
739 | case TIOCGLTC: |
740 | return get_ltchars(real_tty, p); | |
741 | case TIOCSLTC: | |
742 | return set_ltchars(real_tty, p); | |
1da177e4 | 743 | #endif |
355d95a1 AC |
744 | case TCSETSF: |
745 | return set_termios(real_tty, p, TERMIOS_FLUSH | TERMIOS_WAIT | TERMIOS_OLD); | |
746 | case TCSETSW: | |
747 | return set_termios(real_tty, p, TERMIOS_WAIT | TERMIOS_OLD); | |
748 | case TCSETS: | |
749 | return set_termios(real_tty, p, TERMIOS_OLD); | |
edc6afc5 | 750 | #ifndef TCGETS2 |
355d95a1 | 751 | case TCGETS: |
26a2e20f AC |
752 | copy_termios(real_tty, &kterm); |
753 | if (kernel_termios_to_user_termios((struct termios __user *)arg, &kterm)) | |
8f520021 | 754 | ret = -EFAULT; |
8f520021 | 755 | return ret; |
edc6afc5 | 756 | #else |
355d95a1 | 757 | case TCGETS: |
26a2e20f AC |
758 | copy_termios(real_tty, &kterm); |
759 | if (kernel_termios_to_user_termios_1((struct termios __user *)arg, &kterm)) | |
8f520021 | 760 | ret = -EFAULT; |
8f520021 | 761 | return ret; |
355d95a1 | 762 | case TCGETS2: |
26a2e20f AC |
763 | copy_termios(real_tty, &kterm); |
764 | if (kernel_termios_to_user_termios((struct termios2 __user *)arg, &kterm)) | |
8f520021 | 765 | ret = -EFAULT; |
8f520021 | 766 | return ret; |
355d95a1 AC |
767 | case TCSETSF2: |
768 | return set_termios(real_tty, p, TERMIOS_FLUSH | TERMIOS_WAIT); | |
769 | case TCSETSW2: | |
770 | return set_termios(real_tty, p, TERMIOS_WAIT); | |
771 | case TCSETS2: | |
772 | return set_termios(real_tty, p, 0); | |
edc6afc5 | 773 | #endif |
355d95a1 AC |
774 | case TCGETA: |
775 | return get_termio(real_tty, p); | |
776 | case TCSETAF: | |
777 | return set_termios(real_tty, p, TERMIOS_FLUSH | TERMIOS_WAIT | TERMIOS_TERMIO); | |
778 | case TCSETAW: | |
779 | return set_termios(real_tty, p, TERMIOS_WAIT | TERMIOS_TERMIO); | |
780 | case TCSETA: | |
781 | return set_termios(real_tty, p, TERMIOS_TERMIO); | |
0fc00e24 | 782 | #ifndef TCGETS2 |
355d95a1 | 783 | case TIOCGLCKTRMIOS: |
26a2e20f AC |
784 | copy_termios_locked(real_tty, &kterm); |
785 | if (kernel_termios_to_user_termios((struct termios __user *)arg, &kterm)) | |
8f520021 | 786 | ret = -EFAULT; |
8f520021 | 787 | return ret; |
355d95a1 AC |
788 | case TIOCSLCKTRMIOS: |
789 | if (!capable(CAP_SYS_ADMIN)) | |
790 | return -EPERM; | |
26a2e20f AC |
791 | copy_termios_locked(real_tty, &kterm); |
792 | if (user_termios_to_kernel_termios(&kterm, | |
355d95a1 | 793 | (struct termios __user *) arg)) |
26a2e20f | 794 | return -EFAULT; |
6a1c0680 | 795 | down_write(&real_tty->termios_rwsem); |
adc8d746 | 796 | real_tty->termios_locked = kterm; |
6a1c0680 | 797 | up_write(&real_tty->termios_rwsem); |
26a2e20f | 798 | return 0; |
0fc00e24 | 799 | #else |
355d95a1 | 800 | case TIOCGLCKTRMIOS: |
26a2e20f AC |
801 | copy_termios_locked(real_tty, &kterm); |
802 | if (kernel_termios_to_user_termios_1((struct termios __user *)arg, &kterm)) | |
8f520021 | 803 | ret = -EFAULT; |
8f520021 | 804 | return ret; |
355d95a1 AC |
805 | case TIOCSLCKTRMIOS: |
806 | if (!capable(CAP_SYS_ADMIN)) | |
26a2e20f AC |
807 | return -EPERM; |
808 | copy_termios_locked(real_tty, &kterm); | |
809 | if (user_termios_to_kernel_termios_1(&kterm, | |
355d95a1 | 810 | (struct termios __user *) arg)) |
26a2e20f | 811 | return -EFAULT; |
6a1c0680 | 812 | down_write(&real_tty->termios_rwsem); |
adc8d746 | 813 | real_tty->termios_locked = kterm; |
6a1c0680 | 814 | up_write(&real_tty->termios_rwsem); |
8f520021 | 815 | return ret; |
0fc00e24 | 816 | #endif |
1d65b4a0 | 817 | #ifdef TCGETX |
5dca607b MF |
818 | case TCGETX: { |
819 | struct termiox ktermx; | |
1d65b4a0 AC |
820 | if (real_tty->termiox == NULL) |
821 | return -EINVAL; | |
6a1c0680 | 822 | down_read(&real_tty->termios_rwsem); |
26a2e20f | 823 | memcpy(&ktermx, real_tty->termiox, sizeof(struct termiox)); |
6a1c0680 | 824 | up_read(&real_tty->termios_rwsem); |
26a2e20f AC |
825 | if (copy_to_user(p, &ktermx, sizeof(struct termiox))) |
826 | ret = -EFAULT; | |
8f520021 | 827 | return ret; |
5dca607b | 828 | } |
1d65b4a0 AC |
829 | case TCSETX: |
830 | return set_termiox(real_tty, p, 0); | |
831 | case TCSETXW: | |
832 | return set_termiox(real_tty, p, TERMIOS_WAIT); | |
833 | case TCSETXF: | |
834 | return set_termiox(real_tty, p, TERMIOS_FLUSH); | |
835 | #endif | |
355d95a1 | 836 | case TIOCGSOFTCAR: |
26a2e20f AC |
837 | copy_termios(real_tty, &kterm); |
838 | ret = put_user((kterm.c_cflag & CLOCAL) ? 1 : 0, | |
355d95a1 | 839 | (int __user *)arg); |
8f520021 | 840 | return ret; |
355d95a1 AC |
841 | case TIOCSSOFTCAR: |
842 | if (get_user(arg, (unsigned int __user *) arg)) | |
843 | return -EFAULT; | |
f753f327 | 844 | return tty_change_softcar(real_tty, arg); |
355d95a1 AC |
845 | default: |
846 | return -ENOIOCTLCMD; | |
0fc00e24 AC |
847 | } |
848 | } | |
0fc00e24 AC |
849 | EXPORT_SYMBOL_GPL(tty_mode_ioctl); |
850 | ||
e7f3880c PH |
851 | |
852 | /* Caller guarantees ldisc reference is held */ | |
853 | static int __tty_perform_flush(struct tty_struct *tty, unsigned long arg) | |
0fc00e24 | 854 | { |
e7f3880c | 855 | struct tty_ldisc *ld = tty->ldisc; |
0fc00e24 | 856 | |
0fc00e24 AC |
857 | switch (arg) { |
858 | case TCIFLUSH: | |
a1bf9584 | 859 | if (ld && ld->ops->flush_buffer) { |
a352def2 | 860 | ld->ops->flush_buffer(tty); |
a1bf9584 IZ |
861 | tty_unthrottle(tty); |
862 | } | |
0fc00e24 AC |
863 | break; |
864 | case TCIOFLUSH: | |
a1bf9584 | 865 | if (ld && ld->ops->flush_buffer) { |
a352def2 | 866 | ld->ops->flush_buffer(tty); |
a1bf9584 IZ |
867 | tty_unthrottle(tty); |
868 | } | |
df561f66 | 869 | fallthrough; |
0fc00e24 | 870 | case TCOFLUSH: |
f34d7a5b | 871 | tty_driver_flush_buffer(tty); |
0fc00e24 AC |
872 | break; |
873 | default: | |
0fc00e24 AC |
874 | return -EINVAL; |
875 | } | |
0fc00e24 AC |
876 | return 0; |
877 | } | |
e7f3880c PH |
878 | |
879 | int tty_perform_flush(struct tty_struct *tty, unsigned long arg) | |
880 | { | |
881 | struct tty_ldisc *ld; | |
882 | int retval = tty_check_change(tty); | |
883 | if (retval) | |
884 | return retval; | |
885 | ||
886 | ld = tty_ldisc_ref_wait(tty); | |
887 | retval = __tty_perform_flush(tty, arg); | |
888 | if (ld) | |
889 | tty_ldisc_deref(ld); | |
890 | return retval; | |
891 | } | |
0fc00e24 AC |
892 | EXPORT_SYMBOL_GPL(tty_perform_flush); |
893 | ||
47afa7a5 | 894 | int n_tty_ioctl_helper(struct tty_struct *tty, struct file *file, |
0fc00e24 AC |
895 | unsigned int cmd, unsigned long arg) |
896 | { | |
0fc00e24 AC |
897 | int retval; |
898 | ||
0fc00e24 | 899 | switch (cmd) { |
355d95a1 AC |
900 | case TCXONC: |
901 | retval = tty_check_change(tty); | |
902 | if (retval) | |
903 | return retval; | |
904 | switch (arg) { | |
905 | case TCOOFF: | |
c545b66c | 906 | spin_lock_irq(&tty->flow_lock); |
355d95a1 AC |
907 | if (!tty->flow_stopped) { |
908 | tty->flow_stopped = 1; | |
c545b66c | 909 | __stop_tty(tty); |
1da177e4 | 910 | } |
c545b66c | 911 | spin_unlock_irq(&tty->flow_lock); |
355d95a1 AC |
912 | break; |
913 | case TCOON: | |
c545b66c | 914 | spin_lock_irq(&tty->flow_lock); |
355d95a1 AC |
915 | if (tty->flow_stopped) { |
916 | tty->flow_stopped = 0; | |
c545b66c | 917 | __start_tty(tty); |
355d95a1 | 918 | } |
c545b66c | 919 | spin_unlock_irq(&tty->flow_lock); |
355d95a1 AC |
920 | break; |
921 | case TCIOFF: | |
922 | if (STOP_CHAR(tty) != __DISABLED_CHAR) | |
c274f6ef | 923 | retval = tty_send_xchar(tty, STOP_CHAR(tty)); |
355d95a1 AC |
924 | break; |
925 | case TCION: | |
926 | if (START_CHAR(tty) != __DISABLED_CHAR) | |
c274f6ef | 927 | retval = tty_send_xchar(tty, START_CHAR(tty)); |
355d95a1 | 928 | break; |
1da177e4 | 929 | default: |
355d95a1 | 930 | return -EINVAL; |
1da177e4 | 931 | } |
c274f6ef | 932 | return retval; |
355d95a1 | 933 | case TCFLSH: |
5cec7bf6 PH |
934 | retval = tty_check_change(tty); |
935 | if (retval) | |
936 | return retval; | |
e7f3880c | 937 | return __tty_perform_flush(tty, arg); |
355d95a1 AC |
938 | default: |
939 | /* Try the mode commands */ | |
940 | return tty_mode_ioctl(tty, file, cmd, arg); | |
941 | } | |
1da177e4 | 942 | } |
47afa7a5 | 943 | EXPORT_SYMBOL(n_tty_ioctl_helper); |