Commit | Line | Data |
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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> |
9f72cab1 | 24 | #include "tty.h" |
1da177e4 LT |
25 | |
26 | #include <asm/io.h> | |
7c0f6ba6 | 27 | #include <linux/uaccess.h> |
1da177e4 LT |
28 | |
29 | #undef TTY_DEBUG_WAIT_UNTIL_SENT | |
30 | ||
ff8339dc PH |
31 | #ifdef TTY_DEBUG_WAIT_UNTIL_SENT |
32 | # define tty_debug_wait_until_sent(tty, f, args...) tty_debug(tty, f, ##args) | |
33 | #else | |
34 | # define tty_debug_wait_until_sent(tty, f, args...) do {} while (0) | |
35 | #endif | |
36 | ||
1da177e4 LT |
37 | #undef DEBUG |
38 | ||
39 | /* | |
40 | * Internal flag options for termios setting behavior | |
41 | */ | |
42 | #define TERMIOS_FLUSH 1 | |
43 | #define TERMIOS_WAIT 2 | |
44 | #define TERMIOS_TERMIO 4 | |
edc6afc5 | 45 | #define TERMIOS_OLD 8 |
1da177e4 | 46 | |
af9b897e | 47 | |
d81ed103 AC |
48 | /** |
49 | * tty_chars_in_buffer - characters pending | |
50 | * @tty: terminal | |
51 | * | |
52 | * Return the number of bytes of data in the device private | |
53 | * output queue. If no private method is supplied there is assumed | |
54 | * to be no queue on the device. | |
55 | */ | |
56 | ||
fff4ef17 | 57 | unsigned int tty_chars_in_buffer(struct tty_struct *tty) |
f34d7a5b AC |
58 | { |
59 | if (tty->ops->chars_in_buffer) | |
60 | return tty->ops->chars_in_buffer(tty); | |
ab78b0c9 | 61 | return 0; |
f34d7a5b | 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 | ||
03b3b1a2 | 76 | unsigned int tty_write_room(struct tty_struct *tty) |
f34d7a5b AC |
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_unthrottle - flow control | |
101 | * @tty: terminal | |
102 | * | |
103 | * Indicate that a tty may continue 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. | |
107 | * | |
108 | * Drivers should however remember that the stack can issue a throttle, | |
109 | * then change flow control method, then unthrottle. | |
d81ed103 AC |
110 | */ |
111 | ||
39c2e60f AC |
112 | void tty_unthrottle(struct tty_struct *tty) |
113 | { | |
6a1c0680 | 114 | down_write(&tty->termios_rwsem); |
39c2e60f AC |
115 | if (test_and_clear_bit(TTY_THROTTLED, &tty->flags) && |
116 | tty->ops->unthrottle) | |
117 | tty->ops->unthrottle(tty); | |
70bc1264 | 118 | tty->flow_change = 0; |
6a1c0680 | 119 | up_write(&tty->termios_rwsem); |
39c2e60f AC |
120 | } |
121 | EXPORT_SYMBOL(tty_unthrottle); | |
f34d7a5b | 122 | |
70bc1264 PH |
123 | /** |
124 | * tty_throttle_safe - flow control | |
125 | * @tty: terminal | |
126 | * | |
76af233d JS |
127 | * Indicate that a tty should stop transmitting data down the stack. |
128 | * tty_throttle_safe will only attempt throttle if tty->flow_change is | |
129 | * TTY_THROTTLE_SAFE. Prevents an accidental throttle due to race | |
130 | * conditions when throttling is conditional on factors evaluated prior to | |
131 | * throttling. | |
70bc1264 PH |
132 | * |
133 | * Returns 0 if tty is throttled (or was already throttled) | |
134 | */ | |
135 | ||
136 | int tty_throttle_safe(struct tty_struct *tty) | |
137 | { | |
138 | int ret = 0; | |
139 | ||
d8c1f929 | 140 | mutex_lock(&tty->throttle_mutex); |
97ef38b8 | 141 | if (!tty_throttled(tty)) { |
70bc1264 PH |
142 | if (tty->flow_change != TTY_THROTTLE_SAFE) |
143 | ret = 1; | |
144 | else { | |
579a00a5 | 145 | set_bit(TTY_THROTTLED, &tty->flags); |
70bc1264 PH |
146 | if (tty->ops->throttle) |
147 | tty->ops->throttle(tty); | |
148 | } | |
149 | } | |
d8c1f929 | 150 | mutex_unlock(&tty->throttle_mutex); |
70bc1264 PH |
151 | |
152 | return ret; | |
153 | } | |
154 | ||
155 | /** | |
156 | * tty_unthrottle_safe - flow control | |
157 | * @tty: terminal | |
158 | * | |
159 | * Similar to tty_unthrottle() but will only attempt unthrottle | |
160 | * if tty->flow_change is TTY_UNTHROTTLE_SAFE. Prevents an accidental | |
161 | * unthrottle due to race conditions when unthrottling is conditional | |
162 | * on factors evaluated prior to unthrottling. | |
163 | * | |
164 | * Returns 0 if tty is unthrottled (or was already unthrottled) | |
165 | */ | |
166 | ||
167 | int tty_unthrottle_safe(struct tty_struct *tty) | |
168 | { | |
169 | int ret = 0; | |
170 | ||
d8c1f929 | 171 | mutex_lock(&tty->throttle_mutex); |
97ef38b8 | 172 | if (tty_throttled(tty)) { |
70bc1264 PH |
173 | if (tty->flow_change != TTY_UNTHROTTLE_SAFE) |
174 | ret = 1; | |
175 | else { | |
579a00a5 | 176 | clear_bit(TTY_THROTTLED, &tty->flags); |
70bc1264 PH |
177 | if (tty->ops->unthrottle) |
178 | tty->ops->unthrottle(tty); | |
179 | } | |
180 | } | |
d8c1f929 | 181 | mutex_unlock(&tty->throttle_mutex); |
70bc1264 PH |
182 | |
183 | return ret; | |
184 | } | |
185 | ||
af9b897e AC |
186 | /** |
187 | * tty_wait_until_sent - wait for I/O to finish | |
188 | * @tty: tty we are waiting for | |
189 | * @timeout: how long we will wait | |
190 | * | |
191 | * Wait for characters pending in a tty driver to hit the wire, or | |
192 | * for a timeout to occur (eg due to flow control) | |
193 | * | |
194 | * Locking: none | |
195 | */ | |
196 | ||
355d95a1 | 197 | void tty_wait_until_sent(struct tty_struct *tty, long timeout) |
1da177e4 | 198 | { |
d435cefe | 199 | tty_debug_wait_until_sent(tty, "wait until sent, timeout=%ld\n", timeout); |
ff8339dc | 200 | |
1da177e4 LT |
201 | if (!timeout) |
202 | timeout = MAX_SCHEDULE_TIMEOUT; | |
79fbf4a5 | 203 | |
c37bc682 JH |
204 | timeout = wait_event_interruptible_timeout(tty->write_wait, |
205 | !tty_chars_in_buffer(tty), timeout); | |
206 | if (timeout <= 0) | |
79fbf4a5 | 207 | return; |
79fbf4a5 JH |
208 | |
209 | if (timeout == MAX_SCHEDULE_TIMEOUT) | |
210 | timeout = 0; | |
211 | ||
212 | if (tty->ops->wait_until_sent) | |
213 | tty->ops->wait_until_sent(tty, timeout); | |
1da177e4 | 214 | } |
1da177e4 LT |
215 | EXPORT_SYMBOL(tty_wait_until_sent); |
216 | ||
d81ed103 AC |
217 | |
218 | /* | |
219 | * Termios Helper Methods | |
220 | */ | |
221 | ||
d97ba9cd | 222 | static void unset_locked_termios(struct tty_struct *tty, struct ktermios *old) |
1da177e4 | 223 | { |
d97ba9cd PH |
224 | struct ktermios *termios = &tty->termios; |
225 | struct ktermios *locked = &tty->termios_locked; | |
1da177e4 | 226 | int i; |
355d95a1 AC |
227 | |
228 | #define NOSET_MASK(x, y, z) (x = ((x) & ~(z)) | ((y) & (z))) | |
1da177e4 | 229 | |
1da177e4 LT |
230 | NOSET_MASK(termios->c_iflag, old->c_iflag, locked->c_iflag); |
231 | NOSET_MASK(termios->c_oflag, old->c_oflag, locked->c_oflag); | |
232 | NOSET_MASK(termios->c_cflag, old->c_cflag, locked->c_cflag); | |
233 | NOSET_MASK(termios->c_lflag, old->c_lflag, locked->c_lflag); | |
234 | termios->c_line = locked->c_line ? old->c_line : termios->c_line; | |
355d95a1 | 235 | for (i = 0; i < NCCS; i++) |
1da177e4 LT |
236 | termios->c_cc[i] = locked->c_cc[i] ? |
237 | old->c_cc[i] : termios->c_cc[i]; | |
edc6afc5 | 238 | /* FIXME: What should we do for i/ospeed */ |
1da177e4 LT |
239 | } |
240 | ||
5f519d72 AC |
241 | /** |
242 | * tty_termios_copy_hw - copy hardware settings | |
243 | * @new: New termios | |
244 | * @old: Old termios | |
245 | * | |
25985edc | 246 | * Propagate the hardware specific terminal setting bits from |
5f519d72 AC |
247 | * the old termios structure to the new one. This is used in cases |
248 | * where the hardware does not support reconfiguration or as a helper | |
249 | * in some cases where only minimal reconfiguration is supported | |
250 | */ | |
251 | ||
252 | void tty_termios_copy_hw(struct ktermios *new, struct ktermios *old) | |
253 | { | |
254 | /* The bits a dumb device handles in software. Smart devices need | |
255 | to always provide a set_termios method */ | |
256 | new->c_cflag &= HUPCL | CREAD | CLOCAL; | |
257 | new->c_cflag |= old->c_cflag & ~(HUPCL | CREAD | CLOCAL); | |
258 | new->c_ispeed = old->c_ispeed; | |
259 | new->c_ospeed = old->c_ospeed; | |
260 | } | |
5f519d72 AC |
261 | EXPORT_SYMBOL(tty_termios_copy_hw); |
262 | ||
bf5e5834 AC |
263 | /** |
264 | * tty_termios_hw_change - check for setting change | |
265 | * @a: termios | |
266 | * @b: termios to compare | |
267 | * | |
268 | * Check if any of the bits that affect a dumb device have changed | |
269 | * between the two termios structures, or a speed change is needed. | |
270 | */ | |
271 | ||
7b0c6b38 | 272 | int tty_termios_hw_change(const struct ktermios *a, const struct ktermios *b) |
bf5e5834 AC |
273 | { |
274 | if (a->c_ispeed != b->c_ispeed || a->c_ospeed != b->c_ospeed) | |
275 | return 1; | |
276 | if ((a->c_cflag ^ b->c_cflag) & ~(HUPCL | CREAD | CLOCAL)) | |
277 | return 1; | |
278 | return 0; | |
279 | } | |
280 | EXPORT_SYMBOL(tty_termios_hw_change); | |
281 | ||
654ee49b JS |
282 | /** |
283 | * tty_get_char_size - get size of a character | |
284 | * @cflag: termios cflag value | |
285 | * | |
286 | * Get the size (in bits) of a character depending on @cflag's %CSIZE | |
287 | * setting. | |
288 | */ | |
289 | unsigned char tty_get_char_size(unsigned int cflag) | |
290 | { | |
291 | switch (cflag & CSIZE) { | |
292 | case CS5: | |
293 | return 5; | |
294 | case CS6: | |
295 | return 6; | |
296 | case CS7: | |
297 | return 7; | |
298 | case CS8: | |
299 | default: | |
300 | return 8; | |
301 | } | |
302 | } | |
303 | EXPORT_SYMBOL_GPL(tty_get_char_size); | |
304 | ||
305 | /** | |
306 | * tty_get_frame_size - get size of a frame | |
307 | * @cflag: termios cflag value | |
308 | * | |
309 | * Get the size (in bits) of a frame depending on @cflag's %CSIZE, %CSTOPB, | |
310 | * and %PARENB setting. The result is a sum of character size, start and | |
311 | * stop bits -- one bit each -- second stop bit (if set), and parity bit | |
312 | * (if set). | |
313 | */ | |
314 | unsigned char tty_get_frame_size(unsigned int cflag) | |
315 | { | |
316 | unsigned char bits = 2 + tty_get_char_size(cflag); | |
317 | ||
318 | if (cflag & CSTOPB) | |
319 | bits++; | |
320 | if (cflag & PARENB) | |
321 | bits++; | |
4f768e94 IJ |
322 | if (cflag & ADDRB) |
323 | bits++; | |
654ee49b JS |
324 | |
325 | return bits; | |
326 | } | |
327 | EXPORT_SYMBOL_GPL(tty_get_frame_size); | |
328 | ||
af9b897e | 329 | /** |
8d075b19 | 330 | * tty_set_termios - update termios values |
af9b897e AC |
331 | * @tty: tty to update |
332 | * @new_termios: desired new value | |
333 | * | |
dbfcd851 | 334 | * Perform updates to the termios values set on this terminal. |
6460fbbf PH |
335 | * A master pty's termios should never be set. |
336 | * | |
6a1c0680 | 337 | * Locking: termios_rwsem |
af9b897e AC |
338 | */ |
339 | ||
b00f5c2d | 340 | int tty_set_termios(struct tty_struct *tty, struct ktermios *new_termios) |
1da177e4 | 341 | { |
978e595f | 342 | struct ktermios old_termios; |
1da177e4 | 343 | struct tty_ldisc *ld; |
355d95a1 | 344 | |
6460fbbf PH |
345 | WARN_ON(tty->driver->type == TTY_DRIVER_TYPE_PTY && |
346 | tty->driver->subtype == PTY_TYPE_MASTER); | |
1da177e4 LT |
347 | /* |
348 | * Perform the actual termios internal changes under lock. | |
349 | */ | |
355d95a1 | 350 | |
1da177e4 LT |
351 | |
352 | /* FIXME: we need to decide on some locking/ordering semantics | |
353 | for the set_termios notification eventually */ | |
6a1c0680 | 354 | down_write(&tty->termios_rwsem); |
adc8d746 AC |
355 | old_termios = tty->termios; |
356 | tty->termios = *new_termios; | |
d97ba9cd | 357 | unset_locked_termios(tty, &old_termios); |
4f768e94 IJ |
358 | /* Reset any ADDRB changes, ADDRB is changed through ->rs485_config() */ |
359 | tty->termios.c_cflag ^= (tty->termios.c_cflag ^ old_termios.c_cflag) & ADDRB; | |
1da177e4 | 360 | |
f34d7a5b | 361 | if (tty->ops->set_termios) |
c961bfb1 | 362 | tty->ops->set_termios(tty, &old_termios); |
5f519d72 | 363 | else |
adc8d746 | 364 | tty_termios_copy_hw(&tty->termios, &old_termios); |
1da177e4 LT |
365 | |
366 | ld = tty_ldisc_ref(tty); | |
367 | if (ld != NULL) { | |
a352def2 | 368 | if (ld->ops->set_termios) |
c961bfb1 | 369 | ld->ops->set_termios(tty, &old_termios); |
1da177e4 LT |
370 | tty_ldisc_deref(ld); |
371 | } | |
6a1c0680 | 372 | up_write(&tty->termios_rwsem); |
8d075b19 | 373 | return 0; |
1da177e4 | 374 | } |
b00f5c2d | 375 | EXPORT_SYMBOL_GPL(tty_set_termios); |
1da177e4 | 376 | |
af9b897e AC |
377 | /** |
378 | * set_termios - set termios values for a tty | |
379 | * @tty: terminal device | |
380 | * @arg: user data | |
381 | * @opt: option information | |
382 | * | |
3a4fa0a2 | 383 | * Helper function to prepare termios data and run necessary other |
8d075b19 | 384 | * functions before using tty_set_termios to do the actual changes. |
af9b897e AC |
385 | * |
386 | * Locking: | |
6a1c0680 | 387 | * Called functions take ldisc and termios_rwsem locks |
af9b897e AC |
388 | */ |
389 | ||
355d95a1 | 390 | static int set_termios(struct tty_struct *tty, void __user *arg, int opt) |
1da177e4 | 391 | { |
edc6afc5 | 392 | struct ktermios tmp_termios; |
1da177e4 LT |
393 | struct tty_ldisc *ld; |
394 | int retval = tty_check_change(tty); | |
395 | ||
396 | if (retval) | |
397 | return retval; | |
398 | ||
6a1c0680 | 399 | down_read(&tty->termios_rwsem); |
adc8d746 | 400 | tmp_termios = tty->termios; |
6a1c0680 | 401 | up_read(&tty->termios_rwsem); |
64bb6c5e | 402 | |
1da177e4 | 403 | if (opt & TERMIOS_TERMIO) { |
1da177e4 LT |
404 | if (user_termio_to_kernel_termios(&tmp_termios, |
405 | (struct termio __user *)arg)) | |
406 | return -EFAULT; | |
edc6afc5 AC |
407 | #ifdef TCGETS2 |
408 | } else if (opt & TERMIOS_OLD) { | |
edc6afc5 | 409 | if (user_termios_to_kernel_termios_1(&tmp_termios, |
64bb6c5e | 410 | (struct termios __user *)arg)) |
edc6afc5 | 411 | return -EFAULT; |
1da177e4 LT |
412 | } else { |
413 | if (user_termios_to_kernel_termios(&tmp_termios, | |
64bb6c5e | 414 | (struct termios2 __user *)arg)) |
1da177e4 LT |
415 | return -EFAULT; |
416 | } | |
64bb6c5e AC |
417 | #else |
418 | } else if (user_termios_to_kernel_termios(&tmp_termios, | |
419 | (struct termios __user *)arg)) | |
420 | return -EFAULT; | |
421 | #endif | |
1da177e4 | 422 | |
355d95a1 AC |
423 | /* If old style Bfoo values are used then load c_ispeed/c_ospeed |
424 | * with the real speed so its unconditionally usable */ | |
edc6afc5 AC |
425 | tmp_termios.c_ispeed = tty_termios_input_baud_rate(&tmp_termios); |
426 | tmp_termios.c_ospeed = tty_termios_baud_rate(&tmp_termios); | |
427 | ||
1da177e4 | 428 | ld = tty_ldisc_ref(tty); |
355d95a1 | 429 | |
1da177e4 | 430 | if (ld != NULL) { |
a352def2 AC |
431 | if ((opt & TERMIOS_FLUSH) && ld->ops->flush_buffer) |
432 | ld->ops->flush_buffer(tty); | |
1da177e4 LT |
433 | tty_ldisc_deref(ld); |
434 | } | |
355d95a1 | 435 | |
1da177e4 LT |
436 | if (opt & TERMIOS_WAIT) { |
437 | tty_wait_until_sent(tty, 0); | |
438 | if (signal_pending(current)) | |
183d95cd | 439 | return -ERESTARTSYS; |
1da177e4 LT |
440 | } |
441 | ||
8d075b19 | 442 | tty_set_termios(tty, &tmp_termios); |
5f519d72 AC |
443 | |
444 | /* FIXME: Arguably if tmp_termios == tty->termios AND the | |
445 | actual requested termios was not tmp_termios then we may | |
446 | want to return an error as no user requested change has | |
447 | succeeded */ | |
1da177e4 LT |
448 | return 0; |
449 | } | |
450 | ||
26a2e20f AC |
451 | static void copy_termios(struct tty_struct *tty, struct ktermios *kterm) |
452 | { | |
6a1c0680 | 453 | down_read(&tty->termios_rwsem); |
adc8d746 | 454 | *kterm = tty->termios; |
6a1c0680 | 455 | up_read(&tty->termios_rwsem); |
26a2e20f AC |
456 | } |
457 | ||
458 | static void copy_termios_locked(struct tty_struct *tty, struct ktermios *kterm) | |
459 | { | |
6a1c0680 | 460 | down_read(&tty->termios_rwsem); |
adc8d746 | 461 | *kterm = tty->termios_locked; |
6a1c0680 | 462 | up_read(&tty->termios_rwsem); |
26a2e20f AC |
463 | } |
464 | ||
355d95a1 | 465 | static int get_termio(struct tty_struct *tty, struct termio __user *termio) |
1da177e4 | 466 | { |
26a2e20f AC |
467 | struct ktermios kterm; |
468 | copy_termios(tty, &kterm); | |
469 | if (kernel_termios_to_user_termio(termio, &kterm)) | |
1da177e4 LT |
470 | return -EFAULT; |
471 | return 0; | |
472 | } | |
473 | ||
1da177e4 LT |
474 | #ifdef TIOCGETP |
475 | /* | |
476 | * These are deprecated, but there is limited support.. | |
477 | * | |
478 | * The "sg_flags" translation is a joke.. | |
479 | */ | |
355d95a1 | 480 | static int get_sgflags(struct tty_struct *tty) |
1da177e4 LT |
481 | { |
482 | int flags = 0; | |
483 | ||
9db276f8 PH |
484 | if (!L_ICANON(tty)) { |
485 | if (L_ISIG(tty)) | |
1da177e4 LT |
486 | flags |= 0x02; /* cbreak */ |
487 | else | |
488 | flags |= 0x20; /* raw */ | |
489 | } | |
9db276f8 | 490 | if (L_ECHO(tty)) |
1da177e4 | 491 | flags |= 0x08; /* echo */ |
9db276f8 PH |
492 | if (O_OPOST(tty)) |
493 | if (O_ONLCR(tty)) | |
1da177e4 LT |
494 | flags |= 0x10; /* crmod */ |
495 | return flags; | |
496 | } | |
497 | ||
355d95a1 | 498 | static int get_sgttyb(struct tty_struct *tty, struct sgttyb __user *sgttyb) |
1da177e4 LT |
499 | { |
500 | struct sgttyb tmp; | |
501 | ||
6a1c0680 | 502 | down_read(&tty->termios_rwsem); |
adc8d746 AC |
503 | tmp.sg_ispeed = tty->termios.c_ispeed; |
504 | tmp.sg_ospeed = tty->termios.c_ospeed; | |
505 | tmp.sg_erase = tty->termios.c_cc[VERASE]; | |
506 | tmp.sg_kill = tty->termios.c_cc[VKILL]; | |
1da177e4 | 507 | tmp.sg_flags = get_sgflags(tty); |
6a1c0680 | 508 | up_read(&tty->termios_rwsem); |
355d95a1 | 509 | |
1da177e4 LT |
510 | return copy_to_user(sgttyb, &tmp, sizeof(tmp)) ? -EFAULT : 0; |
511 | } | |
512 | ||
355d95a1 | 513 | static void set_sgflags(struct ktermios *termios, int flags) |
1da177e4 | 514 | { |
9833facf AC |
515 | termios->c_iflag = ICRNL | IXON; |
516 | termios->c_oflag = 0; | |
517 | termios->c_lflag = ISIG | ICANON; | |
1da177e4 | 518 | if (flags & 0x02) { /* cbreak */ |
9833facf AC |
519 | termios->c_iflag = 0; |
520 | termios->c_lflag &= ~ICANON; | |
1da177e4 LT |
521 | } |
522 | if (flags & 0x08) { /* echo */ | |
9833facf | 523 | termios->c_lflag |= ECHO | ECHOE | ECHOK | |
1da177e4 LT |
524 | ECHOCTL | ECHOKE | IEXTEN; |
525 | } | |
526 | if (flags & 0x10) { /* crmod */ | |
9833facf | 527 | termios->c_oflag |= OPOST | ONLCR; |
1da177e4 LT |
528 | } |
529 | if (flags & 0x20) { /* raw */ | |
9833facf AC |
530 | termios->c_iflag = 0; |
531 | termios->c_lflag &= ~(ISIG | ICANON); | |
1da177e4 | 532 | } |
9833facf AC |
533 | if (!(termios->c_lflag & ICANON)) { |
534 | termios->c_cc[VMIN] = 1; | |
535 | termios->c_cc[VTIME] = 0; | |
1da177e4 LT |
536 | } |
537 | } | |
538 | ||
af9b897e AC |
539 | /** |
540 | * set_sgttyb - set legacy terminal values | |
541 | * @tty: tty structure | |
542 | * @sgttyb: pointer to old style terminal structure | |
543 | * | |
544 | * Updates a terminal from the legacy BSD style terminal information | |
545 | * structure. | |
546 | * | |
6a1c0680 | 547 | * Locking: termios_rwsem |
af9b897e AC |
548 | */ |
549 | ||
355d95a1 | 550 | static int set_sgttyb(struct tty_struct *tty, struct sgttyb __user *sgttyb) |
1da177e4 LT |
551 | { |
552 | int retval; | |
553 | struct sgttyb tmp; | |
edc6afc5 | 554 | struct ktermios termios; |
1da177e4 LT |
555 | |
556 | retval = tty_check_change(tty); | |
557 | if (retval) | |
558 | return retval; | |
355d95a1 | 559 | |
1da177e4 LT |
560 | if (copy_from_user(&tmp, sgttyb, sizeof(tmp))) |
561 | return -EFAULT; | |
562 | ||
6a1c0680 | 563 | down_write(&tty->termios_rwsem); |
adc8d746 | 564 | termios = tty->termios; |
1da177e4 LT |
565 | termios.c_cc[VERASE] = tmp.sg_erase; |
566 | termios.c_cc[VKILL] = tmp.sg_kill; | |
567 | set_sgflags(&termios, tmp.sg_flags); | |
edc6afc5 | 568 | /* Try and encode into Bfoo format */ |
355d95a1 AC |
569 | tty_termios_encode_baud_rate(&termios, termios.c_ispeed, |
570 | termios.c_ospeed); | |
6a1c0680 | 571 | up_write(&tty->termios_rwsem); |
8d075b19 | 572 | tty_set_termios(tty, &termios); |
1da177e4 LT |
573 | return 0; |
574 | } | |
575 | #endif | |
576 | ||
577 | #ifdef TIOCGETC | |
355d95a1 | 578 | static int get_tchars(struct tty_struct *tty, struct tchars __user *tchars) |
1da177e4 LT |
579 | { |
580 | struct tchars tmp; | |
581 | ||
6a1c0680 | 582 | down_read(&tty->termios_rwsem); |
adc8d746 AC |
583 | tmp.t_intrc = tty->termios.c_cc[VINTR]; |
584 | tmp.t_quitc = tty->termios.c_cc[VQUIT]; | |
585 | tmp.t_startc = tty->termios.c_cc[VSTART]; | |
586 | tmp.t_stopc = tty->termios.c_cc[VSTOP]; | |
587 | tmp.t_eofc = tty->termios.c_cc[VEOF]; | |
588 | tmp.t_brkc = tty->termios.c_cc[VEOL2]; /* what is brkc anyway? */ | |
6a1c0680 | 589 | up_read(&tty->termios_rwsem); |
1da177e4 LT |
590 | return copy_to_user(tchars, &tmp, sizeof(tmp)) ? -EFAULT : 0; |
591 | } | |
592 | ||
355d95a1 | 593 | static int set_tchars(struct tty_struct *tty, struct tchars __user *tchars) |
1da177e4 LT |
594 | { |
595 | struct tchars tmp; | |
596 | ||
597 | if (copy_from_user(&tmp, tchars, sizeof(tmp))) | |
598 | return -EFAULT; | |
6a1c0680 | 599 | down_write(&tty->termios_rwsem); |
adc8d746 AC |
600 | tty->termios.c_cc[VINTR] = tmp.t_intrc; |
601 | tty->termios.c_cc[VQUIT] = tmp.t_quitc; | |
602 | tty->termios.c_cc[VSTART] = tmp.t_startc; | |
603 | tty->termios.c_cc[VSTOP] = tmp.t_stopc; | |
604 | tty->termios.c_cc[VEOF] = tmp.t_eofc; | |
605 | tty->termios.c_cc[VEOL2] = tmp.t_brkc; /* what is brkc anyway? */ | |
6a1c0680 | 606 | up_write(&tty->termios_rwsem); |
1da177e4 LT |
607 | return 0; |
608 | } | |
609 | #endif | |
610 | ||
611 | #ifdef TIOCGLTC | |
355d95a1 | 612 | static int get_ltchars(struct tty_struct *tty, struct ltchars __user *ltchars) |
1da177e4 LT |
613 | { |
614 | struct ltchars tmp; | |
615 | ||
6a1c0680 | 616 | down_read(&tty->termios_rwsem); |
adc8d746 | 617 | tmp.t_suspc = tty->termios.c_cc[VSUSP]; |
355d95a1 | 618 | /* what is dsuspc anyway? */ |
adc8d746 AC |
619 | tmp.t_dsuspc = tty->termios.c_cc[VSUSP]; |
620 | tmp.t_rprntc = tty->termios.c_cc[VREPRINT]; | |
355d95a1 | 621 | /* what is flushc anyway? */ |
adc8d746 AC |
622 | tmp.t_flushc = tty->termios.c_cc[VEOL2]; |
623 | tmp.t_werasc = tty->termios.c_cc[VWERASE]; | |
624 | tmp.t_lnextc = tty->termios.c_cc[VLNEXT]; | |
6a1c0680 | 625 | up_read(&tty->termios_rwsem); |
1da177e4 LT |
626 | return copy_to_user(ltchars, &tmp, sizeof(tmp)) ? -EFAULT : 0; |
627 | } | |
628 | ||
355d95a1 | 629 | static int set_ltchars(struct tty_struct *tty, struct ltchars __user *ltchars) |
1da177e4 LT |
630 | { |
631 | struct ltchars tmp; | |
632 | ||
633 | if (copy_from_user(&tmp, ltchars, sizeof(tmp))) | |
634 | return -EFAULT; | |
635 | ||
6a1c0680 | 636 | down_write(&tty->termios_rwsem); |
adc8d746 | 637 | tty->termios.c_cc[VSUSP] = tmp.t_suspc; |
355d95a1 | 638 | /* what is dsuspc anyway? */ |
adc8d746 AC |
639 | tty->termios.c_cc[VEOL2] = tmp.t_dsuspc; |
640 | tty->termios.c_cc[VREPRINT] = tmp.t_rprntc; | |
355d95a1 | 641 | /* what is flushc anyway? */ |
adc8d746 AC |
642 | tty->termios.c_cc[VEOL2] = tmp.t_flushc; |
643 | tty->termios.c_cc[VWERASE] = tmp.t_werasc; | |
644 | tty->termios.c_cc[VLNEXT] = tmp.t_lnextc; | |
6a1c0680 | 645 | up_write(&tty->termios_rwsem); |
1da177e4 LT |
646 | return 0; |
647 | } | |
648 | #endif | |
649 | ||
1c2630cc AC |
650 | /** |
651 | * tty_change_softcar - carrier change ioctl helper | |
652 | * @tty: tty to update | |
653 | * @arg: enable/disable CLOCAL | |
654 | * | |
655 | * Perform a change to the CLOCAL state and call into the driver | |
6a1c0680 | 656 | * layer to make it visible. All done with the termios rwsem |
1c2630cc AC |
657 | */ |
658 | ||
659 | static int tty_change_softcar(struct tty_struct *tty, int arg) | |
660 | { | |
661 | int ret = 0; | |
662 | int bit = arg ? CLOCAL : 0; | |
f34d7a5b | 663 | struct ktermios old; |
1c2630cc | 664 | |
6a1c0680 | 665 | down_write(&tty->termios_rwsem); |
adc8d746 AC |
666 | old = tty->termios; |
667 | tty->termios.c_cflag &= ~CLOCAL; | |
668 | tty->termios.c_cflag |= bit; | |
f34d7a5b AC |
669 | if (tty->ops->set_termios) |
670 | tty->ops->set_termios(tty, &old); | |
9db276f8 | 671 | if (C_CLOCAL(tty) != bit) |
1c2630cc | 672 | ret = -EINVAL; |
6a1c0680 | 673 | up_write(&tty->termios_rwsem); |
1c2630cc AC |
674 | return ret; |
675 | } | |
676 | ||
0fc00e24 AC |
677 | /** |
678 | * tty_mode_ioctl - mode related ioctls | |
679 | * @tty: tty for the ioctl | |
0fc00e24 AC |
680 | * @cmd: command |
681 | * @arg: ioctl argument | |
682 | * | |
683 | * Perform non line discipline specific mode control ioctls. This | |
684 | * is designed to be called by line disciplines to ensure they provide | |
685 | * consistent mode setting. | |
686 | */ | |
687 | ||
dcc223e8 | 688 | int tty_mode_ioctl(struct tty_struct *tty, unsigned int cmd, unsigned long arg) |
1da177e4 | 689 | { |
355d95a1 | 690 | struct tty_struct *real_tty; |
1da177e4 | 691 | void __user *p = (void __user *)arg; |
8f520021 | 692 | int ret = 0; |
26a2e20f | 693 | struct ktermios kterm; |
1da177e4 LT |
694 | |
695 | if (tty->driver->type == TTY_DRIVER_TYPE_PTY && | |
696 | tty->driver->subtype == PTY_TYPE_MASTER) | |
697 | real_tty = tty->link; | |
698 | else | |
699 | real_tty = tty; | |
700 | ||
701 | switch (cmd) { | |
702 | #ifdef TIOCGETP | |
355d95a1 AC |
703 | case TIOCGETP: |
704 | return get_sgttyb(real_tty, (struct sgttyb __user *) arg); | |
705 | case TIOCSETP: | |
706 | case TIOCSETN: | |
707 | return set_sgttyb(real_tty, (struct sgttyb __user *) arg); | |
1da177e4 LT |
708 | #endif |
709 | #ifdef TIOCGETC | |
355d95a1 AC |
710 | case TIOCGETC: |
711 | return get_tchars(real_tty, p); | |
712 | case TIOCSETC: | |
713 | return set_tchars(real_tty, p); | |
1da177e4 LT |
714 | #endif |
715 | #ifdef TIOCGLTC | |
355d95a1 AC |
716 | case TIOCGLTC: |
717 | return get_ltchars(real_tty, p); | |
718 | case TIOCSLTC: | |
719 | return set_ltchars(real_tty, p); | |
1da177e4 | 720 | #endif |
355d95a1 AC |
721 | case TCSETSF: |
722 | return set_termios(real_tty, p, TERMIOS_FLUSH | TERMIOS_WAIT | TERMIOS_OLD); | |
723 | case TCSETSW: | |
724 | return set_termios(real_tty, p, TERMIOS_WAIT | TERMIOS_OLD); | |
725 | case TCSETS: | |
726 | return set_termios(real_tty, p, TERMIOS_OLD); | |
edc6afc5 | 727 | #ifndef TCGETS2 |
355d95a1 | 728 | case TCGETS: |
26a2e20f AC |
729 | copy_termios(real_tty, &kterm); |
730 | if (kernel_termios_to_user_termios((struct termios __user *)arg, &kterm)) | |
8f520021 | 731 | ret = -EFAULT; |
8f520021 | 732 | return ret; |
edc6afc5 | 733 | #else |
355d95a1 | 734 | case TCGETS: |
26a2e20f AC |
735 | copy_termios(real_tty, &kterm); |
736 | if (kernel_termios_to_user_termios_1((struct termios __user *)arg, &kterm)) | |
8f520021 | 737 | ret = -EFAULT; |
8f520021 | 738 | return ret; |
355d95a1 | 739 | case TCGETS2: |
26a2e20f AC |
740 | copy_termios(real_tty, &kterm); |
741 | if (kernel_termios_to_user_termios((struct termios2 __user *)arg, &kterm)) | |
8f520021 | 742 | ret = -EFAULT; |
8f520021 | 743 | return ret; |
355d95a1 AC |
744 | case TCSETSF2: |
745 | return set_termios(real_tty, p, TERMIOS_FLUSH | TERMIOS_WAIT); | |
746 | case TCSETSW2: | |
747 | return set_termios(real_tty, p, TERMIOS_WAIT); | |
748 | case TCSETS2: | |
749 | return set_termios(real_tty, p, 0); | |
edc6afc5 | 750 | #endif |
355d95a1 AC |
751 | case TCGETA: |
752 | return get_termio(real_tty, p); | |
753 | case TCSETAF: | |
754 | return set_termios(real_tty, p, TERMIOS_FLUSH | TERMIOS_WAIT | TERMIOS_TERMIO); | |
755 | case TCSETAW: | |
756 | return set_termios(real_tty, p, TERMIOS_WAIT | TERMIOS_TERMIO); | |
757 | case TCSETA: | |
758 | return set_termios(real_tty, p, TERMIOS_TERMIO); | |
0fc00e24 | 759 | #ifndef TCGETS2 |
355d95a1 | 760 | case TIOCGLCKTRMIOS: |
26a2e20f AC |
761 | copy_termios_locked(real_tty, &kterm); |
762 | if (kernel_termios_to_user_termios((struct termios __user *)arg, &kterm)) | |
8f520021 | 763 | ret = -EFAULT; |
8f520021 | 764 | return ret; |
355d95a1 AC |
765 | case TIOCSLCKTRMIOS: |
766 | if (!capable(CAP_SYS_ADMIN)) | |
767 | return -EPERM; | |
26a2e20f AC |
768 | copy_termios_locked(real_tty, &kterm); |
769 | if (user_termios_to_kernel_termios(&kterm, | |
355d95a1 | 770 | (struct termios __user *) arg)) |
26a2e20f | 771 | return -EFAULT; |
6a1c0680 | 772 | down_write(&real_tty->termios_rwsem); |
adc8d746 | 773 | real_tty->termios_locked = kterm; |
6a1c0680 | 774 | up_write(&real_tty->termios_rwsem); |
26a2e20f | 775 | return 0; |
0fc00e24 | 776 | #else |
355d95a1 | 777 | case TIOCGLCKTRMIOS: |
26a2e20f AC |
778 | copy_termios_locked(real_tty, &kterm); |
779 | if (kernel_termios_to_user_termios_1((struct termios __user *)arg, &kterm)) | |
8f520021 | 780 | ret = -EFAULT; |
8f520021 | 781 | return ret; |
355d95a1 AC |
782 | case TIOCSLCKTRMIOS: |
783 | if (!capable(CAP_SYS_ADMIN)) | |
26a2e20f AC |
784 | return -EPERM; |
785 | copy_termios_locked(real_tty, &kterm); | |
786 | if (user_termios_to_kernel_termios_1(&kterm, | |
355d95a1 | 787 | (struct termios __user *) arg)) |
26a2e20f | 788 | return -EFAULT; |
6a1c0680 | 789 | down_write(&real_tty->termios_rwsem); |
adc8d746 | 790 | real_tty->termios_locked = kterm; |
6a1c0680 | 791 | up_write(&real_tty->termios_rwsem); |
8f520021 | 792 | return ret; |
0fc00e24 | 793 | #endif |
1d65b4a0 | 794 | #ifdef TCGETX |
e0efb316 | 795 | case TCGETX: |
1d65b4a0 | 796 | case TCSETX: |
1d65b4a0 | 797 | case TCSETXW: |
1d65b4a0 | 798 | case TCSETXF: |
8871de06 JH |
799 | return -ENOTTY; |
800 | #endif | |
355d95a1 | 801 | case TIOCGSOFTCAR: |
26a2e20f AC |
802 | copy_termios(real_tty, &kterm); |
803 | ret = put_user((kterm.c_cflag & CLOCAL) ? 1 : 0, | |
355d95a1 | 804 | (int __user *)arg); |
8f520021 | 805 | return ret; |
355d95a1 AC |
806 | case TIOCSSOFTCAR: |
807 | if (get_user(arg, (unsigned int __user *) arg)) | |
808 | return -EFAULT; | |
f753f327 | 809 | return tty_change_softcar(real_tty, arg); |
355d95a1 AC |
810 | default: |
811 | return -ENOIOCTLCMD; | |
0fc00e24 AC |
812 | } |
813 | } | |
0fc00e24 AC |
814 | EXPORT_SYMBOL_GPL(tty_mode_ioctl); |
815 | ||
e7f3880c PH |
816 | |
817 | /* Caller guarantees ldisc reference is held */ | |
818 | static int __tty_perform_flush(struct tty_struct *tty, unsigned long arg) | |
0fc00e24 | 819 | { |
e7f3880c | 820 | struct tty_ldisc *ld = tty->ldisc; |
0fc00e24 | 821 | |
0fc00e24 AC |
822 | switch (arg) { |
823 | case TCIFLUSH: | |
a1bf9584 | 824 | if (ld && ld->ops->flush_buffer) { |
a352def2 | 825 | ld->ops->flush_buffer(tty); |
a1bf9584 IZ |
826 | tty_unthrottle(tty); |
827 | } | |
0fc00e24 AC |
828 | break; |
829 | case TCIOFLUSH: | |
a1bf9584 | 830 | if (ld && ld->ops->flush_buffer) { |
a352def2 | 831 | ld->ops->flush_buffer(tty); |
a1bf9584 IZ |
832 | tty_unthrottle(tty); |
833 | } | |
df561f66 | 834 | fallthrough; |
0fc00e24 | 835 | case TCOFLUSH: |
f34d7a5b | 836 | tty_driver_flush_buffer(tty); |
0fc00e24 AC |
837 | break; |
838 | default: | |
0fc00e24 AC |
839 | return -EINVAL; |
840 | } | |
0fc00e24 AC |
841 | return 0; |
842 | } | |
e7f3880c PH |
843 | |
844 | int tty_perform_flush(struct tty_struct *tty, unsigned long arg) | |
845 | { | |
846 | struct tty_ldisc *ld; | |
847 | int retval = tty_check_change(tty); | |
848 | if (retval) | |
849 | return retval; | |
850 | ||
851 | ld = tty_ldisc_ref_wait(tty); | |
852 | retval = __tty_perform_flush(tty, arg); | |
853 | if (ld) | |
854 | tty_ldisc_deref(ld); | |
855 | return retval; | |
856 | } | |
0fc00e24 AC |
857 | EXPORT_SYMBOL_GPL(tty_perform_flush); |
858 | ||
7c783601 JS |
859 | int n_tty_ioctl_helper(struct tty_struct *tty, unsigned int cmd, |
860 | unsigned long arg) | |
0fc00e24 | 861 | { |
0fc00e24 AC |
862 | int retval; |
863 | ||
0fc00e24 | 864 | switch (cmd) { |
355d95a1 AC |
865 | case TCXONC: |
866 | retval = tty_check_change(tty); | |
867 | if (retval) | |
868 | return retval; | |
869 | switch (arg) { | |
870 | case TCOOFF: | |
6e94dbc7 JS |
871 | spin_lock_irq(&tty->flow.lock); |
872 | if (!tty->flow.tco_stopped) { | |
873 | tty->flow.tco_stopped = true; | |
c545b66c | 874 | __stop_tty(tty); |
1da177e4 | 875 | } |
6e94dbc7 | 876 | spin_unlock_irq(&tty->flow.lock); |
355d95a1 AC |
877 | break; |
878 | case TCOON: | |
6e94dbc7 JS |
879 | spin_lock_irq(&tty->flow.lock); |
880 | if (tty->flow.tco_stopped) { | |
881 | tty->flow.tco_stopped = false; | |
c545b66c | 882 | __start_tty(tty); |
355d95a1 | 883 | } |
6e94dbc7 | 884 | spin_unlock_irq(&tty->flow.lock); |
355d95a1 AC |
885 | break; |
886 | case TCIOFF: | |
887 | if (STOP_CHAR(tty) != __DISABLED_CHAR) | |
c274f6ef | 888 | retval = tty_send_xchar(tty, STOP_CHAR(tty)); |
355d95a1 AC |
889 | break; |
890 | case TCION: | |
891 | if (START_CHAR(tty) != __DISABLED_CHAR) | |
c274f6ef | 892 | retval = tty_send_xchar(tty, START_CHAR(tty)); |
355d95a1 | 893 | break; |
1da177e4 | 894 | default: |
355d95a1 | 895 | return -EINVAL; |
1da177e4 | 896 | } |
c274f6ef | 897 | return retval; |
355d95a1 | 898 | case TCFLSH: |
5cec7bf6 PH |
899 | retval = tty_check_change(tty); |
900 | if (retval) | |
901 | return retval; | |
e7f3880c | 902 | return __tty_perform_flush(tty, arg); |
355d95a1 AC |
903 | default: |
904 | /* Try the mode commands */ | |
dcc223e8 | 905 | return tty_mode_ioctl(tty, cmd, arg); |
355d95a1 | 906 | } |
1da177e4 | 907 | } |
47afa7a5 | 908 | EXPORT_SYMBOL(n_tty_ioctl_helper); |