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> |
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); | |
ab78b0c9 | 60 | return 0; |
f34d7a5b | 61 | } |
f34d7a5b AC |
62 | EXPORT_SYMBOL(tty_chars_in_buffer); |
63 | ||
d81ed103 AC |
64 | /** |
65 | * tty_write_room - write queue space | |
66 | * @tty: terminal | |
67 | * | |
68 | * Return the number of bytes that can be queued to this device | |
69 | * at the present time. The result should be treated as a guarantee | |
70 | * and the driver cannot offer a value it later shrinks by more than | |
71 | * the number of bytes written. If no method is provided 2K is always | |
72 | * returned and data may be lost as there will be no flow control. | |
73 | */ | |
74 | ||
f34d7a5b AC |
75 | int tty_write_room(struct tty_struct *tty) |
76 | { | |
77 | if (tty->ops->write_room) | |
78 | return tty->ops->write_room(tty); | |
79 | return 2048; | |
80 | } | |
f34d7a5b AC |
81 | EXPORT_SYMBOL(tty_write_room); |
82 | ||
d81ed103 AC |
83 | /** |
84 | * tty_driver_flush_buffer - discard internal buffer | |
85 | * @tty: terminal | |
86 | * | |
87 | * Discard the internal output buffer for this device. If no method | |
88 | * is provided then either the buffer cannot be hardware flushed or | |
89 | * there is no buffer driver side. | |
90 | */ | |
f34d7a5b AC |
91 | void tty_driver_flush_buffer(struct tty_struct *tty) |
92 | { | |
93 | if (tty->ops->flush_buffer) | |
94 | tty->ops->flush_buffer(tty); | |
95 | } | |
f34d7a5b AC |
96 | EXPORT_SYMBOL(tty_driver_flush_buffer); |
97 | ||
d81ed103 AC |
98 | /** |
99 | * tty_throttle - flow control | |
100 | * @tty: terminal | |
101 | * | |
102 | * Indicate that a tty should stop transmitting data down the stack. | |
6a1c0680 | 103 | * Takes the termios rwsem to protect against parallel throttle/unthrottle |
38db8979 AC |
104 | * and also to ensure the driver can consistently reference its own |
105 | * termios data at this point when implementing software flow control. | |
d81ed103 AC |
106 | */ |
107 | ||
39c2e60f AC |
108 | void tty_throttle(struct tty_struct *tty) |
109 | { | |
6a1c0680 | 110 | down_write(&tty->termios_rwsem); |
39c2e60f AC |
111 | /* check TTY_THROTTLED first so it indicates our state */ |
112 | if (!test_and_set_bit(TTY_THROTTLED, &tty->flags) && | |
113 | tty->ops->throttle) | |
114 | tty->ops->throttle(tty); | |
70bc1264 | 115 | tty->flow_change = 0; |
6a1c0680 | 116 | up_write(&tty->termios_rwsem); |
39c2e60f AC |
117 | } |
118 | EXPORT_SYMBOL(tty_throttle); | |
119 | ||
d81ed103 AC |
120 | /** |
121 | * tty_unthrottle - flow control | |
122 | * @tty: terminal | |
123 | * | |
124 | * Indicate that a tty may continue transmitting data down the stack. | |
6a1c0680 | 125 | * Takes the termios rwsem to protect against parallel throttle/unthrottle |
38db8979 AC |
126 | * and also to ensure the driver can consistently reference its own |
127 | * termios data at this point when implementing software flow control. | |
128 | * | |
129 | * Drivers should however remember that the stack can issue a throttle, | |
130 | * then change flow control method, then unthrottle. | |
d81ed103 AC |
131 | */ |
132 | ||
39c2e60f AC |
133 | void tty_unthrottle(struct tty_struct *tty) |
134 | { | |
6a1c0680 | 135 | down_write(&tty->termios_rwsem); |
39c2e60f AC |
136 | if (test_and_clear_bit(TTY_THROTTLED, &tty->flags) && |
137 | tty->ops->unthrottle) | |
138 | tty->ops->unthrottle(tty); | |
70bc1264 | 139 | tty->flow_change = 0; |
6a1c0680 | 140 | up_write(&tty->termios_rwsem); |
39c2e60f AC |
141 | } |
142 | EXPORT_SYMBOL(tty_unthrottle); | |
f34d7a5b | 143 | |
70bc1264 PH |
144 | /** |
145 | * tty_throttle_safe - flow control | |
146 | * @tty: terminal | |
147 | * | |
148 | * Similar to tty_throttle() but will only attempt throttle | |
149 | * if tty->flow_change is TTY_THROTTLE_SAFE. Prevents an accidental | |
150 | * throttle due to race conditions when throttling is conditional | |
151 | * on factors evaluated prior to throttling. | |
152 | * | |
153 | * Returns 0 if tty is throttled (or was already throttled) | |
154 | */ | |
155 | ||
156 | int tty_throttle_safe(struct tty_struct *tty) | |
157 | { | |
158 | int ret = 0; | |
159 | ||
d8c1f929 | 160 | mutex_lock(&tty->throttle_mutex); |
97ef38b8 | 161 | if (!tty_throttled(tty)) { |
70bc1264 PH |
162 | if (tty->flow_change != TTY_THROTTLE_SAFE) |
163 | ret = 1; | |
164 | else { | |
579a00a5 | 165 | set_bit(TTY_THROTTLED, &tty->flags); |
70bc1264 PH |
166 | if (tty->ops->throttle) |
167 | tty->ops->throttle(tty); | |
168 | } | |
169 | } | |
d8c1f929 | 170 | mutex_unlock(&tty->throttle_mutex); |
70bc1264 PH |
171 | |
172 | return ret; | |
173 | } | |
174 | ||
175 | /** | |
176 | * tty_unthrottle_safe - flow control | |
177 | * @tty: terminal | |
178 | * | |
179 | * Similar to tty_unthrottle() but will only attempt unthrottle | |
180 | * if tty->flow_change is TTY_UNTHROTTLE_SAFE. Prevents an accidental | |
181 | * unthrottle due to race conditions when unthrottling is conditional | |
182 | * on factors evaluated prior to unthrottling. | |
183 | * | |
184 | * Returns 0 if tty is unthrottled (or was already unthrottled) | |
185 | */ | |
186 | ||
187 | int tty_unthrottle_safe(struct tty_struct *tty) | |
188 | { | |
189 | int ret = 0; | |
190 | ||
d8c1f929 | 191 | mutex_lock(&tty->throttle_mutex); |
97ef38b8 | 192 | if (tty_throttled(tty)) { |
70bc1264 PH |
193 | if (tty->flow_change != TTY_UNTHROTTLE_SAFE) |
194 | ret = 1; | |
195 | else { | |
579a00a5 | 196 | clear_bit(TTY_THROTTLED, &tty->flags); |
70bc1264 PH |
197 | if (tty->ops->unthrottle) |
198 | tty->ops->unthrottle(tty); | |
199 | } | |
200 | } | |
d8c1f929 | 201 | mutex_unlock(&tty->throttle_mutex); |
70bc1264 PH |
202 | |
203 | return ret; | |
204 | } | |
205 | ||
af9b897e AC |
206 | /** |
207 | * tty_wait_until_sent - wait for I/O to finish | |
208 | * @tty: tty we are waiting for | |
209 | * @timeout: how long we will wait | |
210 | * | |
211 | * Wait for characters pending in a tty driver to hit the wire, or | |
212 | * for a timeout to occur (eg due to flow control) | |
213 | * | |
214 | * Locking: none | |
215 | */ | |
216 | ||
355d95a1 | 217 | void tty_wait_until_sent(struct tty_struct *tty, long timeout) |
1da177e4 | 218 | { |
d435cefe | 219 | tty_debug_wait_until_sent(tty, "wait until sent, timeout=%ld\n", timeout); |
ff8339dc | 220 | |
1da177e4 LT |
221 | if (!timeout) |
222 | timeout = MAX_SCHEDULE_TIMEOUT; | |
79fbf4a5 | 223 | |
c37bc682 JH |
224 | timeout = wait_event_interruptible_timeout(tty->write_wait, |
225 | !tty_chars_in_buffer(tty), timeout); | |
226 | if (timeout <= 0) | |
79fbf4a5 | 227 | return; |
79fbf4a5 JH |
228 | |
229 | if (timeout == MAX_SCHEDULE_TIMEOUT) | |
230 | timeout = 0; | |
231 | ||
232 | if (tty->ops->wait_until_sent) | |
233 | tty->ops->wait_until_sent(tty, timeout); | |
1da177e4 | 234 | } |
1da177e4 LT |
235 | EXPORT_SYMBOL(tty_wait_until_sent); |
236 | ||
d81ed103 AC |
237 | |
238 | /* | |
239 | * Termios Helper Methods | |
240 | */ | |
241 | ||
d97ba9cd | 242 | static void unset_locked_termios(struct tty_struct *tty, struct ktermios *old) |
1da177e4 | 243 | { |
d97ba9cd PH |
244 | struct ktermios *termios = &tty->termios; |
245 | struct ktermios *locked = &tty->termios_locked; | |
1da177e4 | 246 | int i; |
355d95a1 AC |
247 | |
248 | #define NOSET_MASK(x, y, z) (x = ((x) & ~(z)) | ((y) & (z))) | |
1da177e4 | 249 | |
1da177e4 LT |
250 | NOSET_MASK(termios->c_iflag, old->c_iflag, locked->c_iflag); |
251 | NOSET_MASK(termios->c_oflag, old->c_oflag, locked->c_oflag); | |
252 | NOSET_MASK(termios->c_cflag, old->c_cflag, locked->c_cflag); | |
253 | NOSET_MASK(termios->c_lflag, old->c_lflag, locked->c_lflag); | |
254 | termios->c_line = locked->c_line ? old->c_line : termios->c_line; | |
355d95a1 | 255 | for (i = 0; i < NCCS; i++) |
1da177e4 LT |
256 | termios->c_cc[i] = locked->c_cc[i] ? |
257 | old->c_cc[i] : termios->c_cc[i]; | |
edc6afc5 | 258 | /* FIXME: What should we do for i/ospeed */ |
1da177e4 LT |
259 | } |
260 | ||
5f519d72 AC |
261 | /** |
262 | * tty_termios_copy_hw - copy hardware settings | |
263 | * @new: New termios | |
264 | * @old: Old termios | |
265 | * | |
25985edc | 266 | * Propagate the hardware specific terminal setting bits from |
5f519d72 AC |
267 | * the old termios structure to the new one. This is used in cases |
268 | * where the hardware does not support reconfiguration or as a helper | |
269 | * in some cases where only minimal reconfiguration is supported | |
270 | */ | |
271 | ||
272 | void tty_termios_copy_hw(struct ktermios *new, struct ktermios *old) | |
273 | { | |
274 | /* The bits a dumb device handles in software. Smart devices need | |
275 | to always provide a set_termios method */ | |
276 | new->c_cflag &= HUPCL | CREAD | CLOCAL; | |
277 | new->c_cflag |= old->c_cflag & ~(HUPCL | CREAD | CLOCAL); | |
278 | new->c_ispeed = old->c_ispeed; | |
279 | new->c_ospeed = old->c_ospeed; | |
280 | } | |
5f519d72 AC |
281 | EXPORT_SYMBOL(tty_termios_copy_hw); |
282 | ||
bf5e5834 AC |
283 | /** |
284 | * tty_termios_hw_change - check for setting change | |
285 | * @a: termios | |
286 | * @b: termios to compare | |
287 | * | |
288 | * Check if any of the bits that affect a dumb device have changed | |
289 | * between the two termios structures, or a speed change is needed. | |
290 | */ | |
291 | ||
7b0c6b38 | 292 | int tty_termios_hw_change(const struct ktermios *a, const struct ktermios *b) |
bf5e5834 AC |
293 | { |
294 | if (a->c_ispeed != b->c_ispeed || a->c_ospeed != b->c_ospeed) | |
295 | return 1; | |
296 | if ((a->c_cflag ^ b->c_cflag) & ~(HUPCL | CREAD | CLOCAL)) | |
297 | return 1; | |
298 | return 0; | |
299 | } | |
300 | EXPORT_SYMBOL(tty_termios_hw_change); | |
301 | ||
af9b897e | 302 | /** |
8d075b19 | 303 | * tty_set_termios - update termios values |
af9b897e AC |
304 | * @tty: tty to update |
305 | * @new_termios: desired new value | |
306 | * | |
dbfcd851 | 307 | * Perform updates to the termios values set on this terminal. |
6460fbbf PH |
308 | * A master pty's termios should never be set. |
309 | * | |
6a1c0680 | 310 | * Locking: termios_rwsem |
af9b897e AC |
311 | */ |
312 | ||
b00f5c2d | 313 | int tty_set_termios(struct tty_struct *tty, struct ktermios *new_termios) |
1da177e4 | 314 | { |
978e595f | 315 | struct ktermios old_termios; |
1da177e4 | 316 | struct tty_ldisc *ld; |
355d95a1 | 317 | |
6460fbbf PH |
318 | WARN_ON(tty->driver->type == TTY_DRIVER_TYPE_PTY && |
319 | tty->driver->subtype == PTY_TYPE_MASTER); | |
1da177e4 LT |
320 | /* |
321 | * Perform the actual termios internal changes under lock. | |
322 | */ | |
355d95a1 | 323 | |
1da177e4 LT |
324 | |
325 | /* FIXME: we need to decide on some locking/ordering semantics | |
326 | for the set_termios notification eventually */ | |
6a1c0680 | 327 | down_write(&tty->termios_rwsem); |
adc8d746 AC |
328 | old_termios = tty->termios; |
329 | tty->termios = *new_termios; | |
d97ba9cd | 330 | unset_locked_termios(tty, &old_termios); |
1da177e4 | 331 | |
f34d7a5b | 332 | if (tty->ops->set_termios) |
c961bfb1 | 333 | tty->ops->set_termios(tty, &old_termios); |
5f519d72 | 334 | else |
adc8d746 | 335 | tty_termios_copy_hw(&tty->termios, &old_termios); |
1da177e4 LT |
336 | |
337 | ld = tty_ldisc_ref(tty); | |
338 | if (ld != NULL) { | |
a352def2 | 339 | if (ld->ops->set_termios) |
c961bfb1 | 340 | ld->ops->set_termios(tty, &old_termios); |
1da177e4 LT |
341 | tty_ldisc_deref(ld); |
342 | } | |
6a1c0680 | 343 | up_write(&tty->termios_rwsem); |
8d075b19 | 344 | return 0; |
1da177e4 | 345 | } |
b00f5c2d | 346 | EXPORT_SYMBOL_GPL(tty_set_termios); |
1da177e4 | 347 | |
af9b897e AC |
348 | /** |
349 | * set_termios - set termios values for a tty | |
350 | * @tty: terminal device | |
351 | * @arg: user data | |
352 | * @opt: option information | |
353 | * | |
3a4fa0a2 | 354 | * Helper function to prepare termios data and run necessary other |
8d075b19 | 355 | * functions before using tty_set_termios to do the actual changes. |
af9b897e AC |
356 | * |
357 | * Locking: | |
6a1c0680 | 358 | * Called functions take ldisc and termios_rwsem locks |
af9b897e AC |
359 | */ |
360 | ||
355d95a1 | 361 | static int set_termios(struct tty_struct *tty, void __user *arg, int opt) |
1da177e4 | 362 | { |
edc6afc5 | 363 | struct ktermios tmp_termios; |
1da177e4 LT |
364 | struct tty_ldisc *ld; |
365 | int retval = tty_check_change(tty); | |
366 | ||
367 | if (retval) | |
368 | return retval; | |
369 | ||
6a1c0680 | 370 | down_read(&tty->termios_rwsem); |
adc8d746 | 371 | tmp_termios = tty->termios; |
6a1c0680 | 372 | up_read(&tty->termios_rwsem); |
64bb6c5e | 373 | |
1da177e4 | 374 | if (opt & TERMIOS_TERMIO) { |
1da177e4 LT |
375 | if (user_termio_to_kernel_termios(&tmp_termios, |
376 | (struct termio __user *)arg)) | |
377 | return -EFAULT; | |
edc6afc5 AC |
378 | #ifdef TCGETS2 |
379 | } else if (opt & TERMIOS_OLD) { | |
edc6afc5 | 380 | if (user_termios_to_kernel_termios_1(&tmp_termios, |
64bb6c5e | 381 | (struct termios __user *)arg)) |
edc6afc5 | 382 | return -EFAULT; |
1da177e4 LT |
383 | } else { |
384 | if (user_termios_to_kernel_termios(&tmp_termios, | |
64bb6c5e | 385 | (struct termios2 __user *)arg)) |
1da177e4 LT |
386 | return -EFAULT; |
387 | } | |
64bb6c5e AC |
388 | #else |
389 | } else if (user_termios_to_kernel_termios(&tmp_termios, | |
390 | (struct termios __user *)arg)) | |
391 | return -EFAULT; | |
392 | #endif | |
1da177e4 | 393 | |
355d95a1 AC |
394 | /* If old style Bfoo values are used then load c_ispeed/c_ospeed |
395 | * with the real speed so its unconditionally usable */ | |
edc6afc5 AC |
396 | tmp_termios.c_ispeed = tty_termios_input_baud_rate(&tmp_termios); |
397 | tmp_termios.c_ospeed = tty_termios_baud_rate(&tmp_termios); | |
398 | ||
1da177e4 | 399 | ld = tty_ldisc_ref(tty); |
355d95a1 | 400 | |
1da177e4 | 401 | if (ld != NULL) { |
a352def2 AC |
402 | if ((opt & TERMIOS_FLUSH) && ld->ops->flush_buffer) |
403 | ld->ops->flush_buffer(tty); | |
1da177e4 LT |
404 | tty_ldisc_deref(ld); |
405 | } | |
355d95a1 | 406 | |
1da177e4 LT |
407 | if (opt & TERMIOS_WAIT) { |
408 | tty_wait_until_sent(tty, 0); | |
409 | if (signal_pending(current)) | |
183d95cd | 410 | return -ERESTARTSYS; |
1da177e4 LT |
411 | } |
412 | ||
8d075b19 | 413 | tty_set_termios(tty, &tmp_termios); |
5f519d72 AC |
414 | |
415 | /* FIXME: Arguably if tmp_termios == tty->termios AND the | |
416 | actual requested termios was not tmp_termios then we may | |
417 | want to return an error as no user requested change has | |
418 | succeeded */ | |
1da177e4 LT |
419 | return 0; |
420 | } | |
421 | ||
26a2e20f AC |
422 | static void copy_termios(struct tty_struct *tty, struct ktermios *kterm) |
423 | { | |
6a1c0680 | 424 | down_read(&tty->termios_rwsem); |
adc8d746 | 425 | *kterm = tty->termios; |
6a1c0680 | 426 | up_read(&tty->termios_rwsem); |
26a2e20f AC |
427 | } |
428 | ||
429 | static void copy_termios_locked(struct tty_struct *tty, struct ktermios *kterm) | |
430 | { | |
6a1c0680 | 431 | down_read(&tty->termios_rwsem); |
adc8d746 | 432 | *kterm = tty->termios_locked; |
6a1c0680 | 433 | up_read(&tty->termios_rwsem); |
26a2e20f AC |
434 | } |
435 | ||
355d95a1 | 436 | static int get_termio(struct tty_struct *tty, struct termio __user *termio) |
1da177e4 | 437 | { |
26a2e20f AC |
438 | struct ktermios kterm; |
439 | copy_termios(tty, &kterm); | |
440 | if (kernel_termios_to_user_termio(termio, &kterm)) | |
1da177e4 LT |
441 | return -EFAULT; |
442 | return 0; | |
443 | } | |
444 | ||
1da177e4 LT |
445 | #ifdef TIOCGETP |
446 | /* | |
447 | * These are deprecated, but there is limited support.. | |
448 | * | |
449 | * The "sg_flags" translation is a joke.. | |
450 | */ | |
355d95a1 | 451 | static int get_sgflags(struct tty_struct *tty) |
1da177e4 LT |
452 | { |
453 | int flags = 0; | |
454 | ||
9db276f8 PH |
455 | if (!L_ICANON(tty)) { |
456 | if (L_ISIG(tty)) | |
1da177e4 LT |
457 | flags |= 0x02; /* cbreak */ |
458 | else | |
459 | flags |= 0x20; /* raw */ | |
460 | } | |
9db276f8 | 461 | if (L_ECHO(tty)) |
1da177e4 | 462 | flags |= 0x08; /* echo */ |
9db276f8 PH |
463 | if (O_OPOST(tty)) |
464 | if (O_ONLCR(tty)) | |
1da177e4 LT |
465 | flags |= 0x10; /* crmod */ |
466 | return flags; | |
467 | } | |
468 | ||
355d95a1 | 469 | static int get_sgttyb(struct tty_struct *tty, struct sgttyb __user *sgttyb) |
1da177e4 LT |
470 | { |
471 | struct sgttyb tmp; | |
472 | ||
6a1c0680 | 473 | down_read(&tty->termios_rwsem); |
adc8d746 AC |
474 | tmp.sg_ispeed = tty->termios.c_ispeed; |
475 | tmp.sg_ospeed = tty->termios.c_ospeed; | |
476 | tmp.sg_erase = tty->termios.c_cc[VERASE]; | |
477 | tmp.sg_kill = tty->termios.c_cc[VKILL]; | |
1da177e4 | 478 | tmp.sg_flags = get_sgflags(tty); |
6a1c0680 | 479 | up_read(&tty->termios_rwsem); |
355d95a1 | 480 | |
1da177e4 LT |
481 | return copy_to_user(sgttyb, &tmp, sizeof(tmp)) ? -EFAULT : 0; |
482 | } | |
483 | ||
355d95a1 | 484 | static void set_sgflags(struct ktermios *termios, int flags) |
1da177e4 | 485 | { |
9833facf AC |
486 | termios->c_iflag = ICRNL | IXON; |
487 | termios->c_oflag = 0; | |
488 | termios->c_lflag = ISIG | ICANON; | |
1da177e4 | 489 | if (flags & 0x02) { /* cbreak */ |
9833facf AC |
490 | termios->c_iflag = 0; |
491 | termios->c_lflag &= ~ICANON; | |
1da177e4 LT |
492 | } |
493 | if (flags & 0x08) { /* echo */ | |
9833facf | 494 | termios->c_lflag |= ECHO | ECHOE | ECHOK | |
1da177e4 LT |
495 | ECHOCTL | ECHOKE | IEXTEN; |
496 | } | |
497 | if (flags & 0x10) { /* crmod */ | |
9833facf | 498 | termios->c_oflag |= OPOST | ONLCR; |
1da177e4 LT |
499 | } |
500 | if (flags & 0x20) { /* raw */ | |
9833facf AC |
501 | termios->c_iflag = 0; |
502 | termios->c_lflag &= ~(ISIG | ICANON); | |
1da177e4 | 503 | } |
9833facf AC |
504 | if (!(termios->c_lflag & ICANON)) { |
505 | termios->c_cc[VMIN] = 1; | |
506 | termios->c_cc[VTIME] = 0; | |
1da177e4 LT |
507 | } |
508 | } | |
509 | ||
af9b897e AC |
510 | /** |
511 | * set_sgttyb - set legacy terminal values | |
512 | * @tty: tty structure | |
513 | * @sgttyb: pointer to old style terminal structure | |
514 | * | |
515 | * Updates a terminal from the legacy BSD style terminal information | |
516 | * structure. | |
517 | * | |
6a1c0680 | 518 | * Locking: termios_rwsem |
af9b897e AC |
519 | */ |
520 | ||
355d95a1 | 521 | static int set_sgttyb(struct tty_struct *tty, struct sgttyb __user *sgttyb) |
1da177e4 LT |
522 | { |
523 | int retval; | |
524 | struct sgttyb tmp; | |
edc6afc5 | 525 | struct ktermios termios; |
1da177e4 LT |
526 | |
527 | retval = tty_check_change(tty); | |
528 | if (retval) | |
529 | return retval; | |
355d95a1 | 530 | |
1da177e4 LT |
531 | if (copy_from_user(&tmp, sgttyb, sizeof(tmp))) |
532 | return -EFAULT; | |
533 | ||
6a1c0680 | 534 | down_write(&tty->termios_rwsem); |
adc8d746 | 535 | termios = tty->termios; |
1da177e4 LT |
536 | termios.c_cc[VERASE] = tmp.sg_erase; |
537 | termios.c_cc[VKILL] = tmp.sg_kill; | |
538 | set_sgflags(&termios, tmp.sg_flags); | |
edc6afc5 AC |
539 | /* Try and encode into Bfoo format */ |
540 | #ifdef BOTHER | |
355d95a1 AC |
541 | tty_termios_encode_baud_rate(&termios, termios.c_ispeed, |
542 | termios.c_ospeed); | |
edc6afc5 | 543 | #endif |
6a1c0680 | 544 | up_write(&tty->termios_rwsem); |
8d075b19 | 545 | tty_set_termios(tty, &termios); |
1da177e4 LT |
546 | return 0; |
547 | } | |
548 | #endif | |
549 | ||
550 | #ifdef TIOCGETC | |
355d95a1 | 551 | static int get_tchars(struct tty_struct *tty, struct tchars __user *tchars) |
1da177e4 LT |
552 | { |
553 | struct tchars tmp; | |
554 | ||
6a1c0680 | 555 | down_read(&tty->termios_rwsem); |
adc8d746 AC |
556 | tmp.t_intrc = tty->termios.c_cc[VINTR]; |
557 | tmp.t_quitc = tty->termios.c_cc[VQUIT]; | |
558 | tmp.t_startc = tty->termios.c_cc[VSTART]; | |
559 | tmp.t_stopc = tty->termios.c_cc[VSTOP]; | |
560 | tmp.t_eofc = tty->termios.c_cc[VEOF]; | |
561 | tmp.t_brkc = tty->termios.c_cc[VEOL2]; /* what is brkc anyway? */ | |
6a1c0680 | 562 | up_read(&tty->termios_rwsem); |
1da177e4 LT |
563 | return copy_to_user(tchars, &tmp, sizeof(tmp)) ? -EFAULT : 0; |
564 | } | |
565 | ||
355d95a1 | 566 | static int set_tchars(struct tty_struct *tty, struct tchars __user *tchars) |
1da177e4 LT |
567 | { |
568 | struct tchars tmp; | |
569 | ||
570 | if (copy_from_user(&tmp, tchars, sizeof(tmp))) | |
571 | return -EFAULT; | |
6a1c0680 | 572 | down_write(&tty->termios_rwsem); |
adc8d746 AC |
573 | tty->termios.c_cc[VINTR] = tmp.t_intrc; |
574 | tty->termios.c_cc[VQUIT] = tmp.t_quitc; | |
575 | tty->termios.c_cc[VSTART] = tmp.t_startc; | |
576 | tty->termios.c_cc[VSTOP] = tmp.t_stopc; | |
577 | tty->termios.c_cc[VEOF] = tmp.t_eofc; | |
578 | tty->termios.c_cc[VEOL2] = tmp.t_brkc; /* what is brkc anyway? */ | |
6a1c0680 | 579 | up_write(&tty->termios_rwsem); |
1da177e4 LT |
580 | return 0; |
581 | } | |
582 | #endif | |
583 | ||
584 | #ifdef TIOCGLTC | |
355d95a1 | 585 | static int get_ltchars(struct tty_struct *tty, struct ltchars __user *ltchars) |
1da177e4 LT |
586 | { |
587 | struct ltchars tmp; | |
588 | ||
6a1c0680 | 589 | down_read(&tty->termios_rwsem); |
adc8d746 | 590 | tmp.t_suspc = tty->termios.c_cc[VSUSP]; |
355d95a1 | 591 | /* what is dsuspc anyway? */ |
adc8d746 AC |
592 | tmp.t_dsuspc = tty->termios.c_cc[VSUSP]; |
593 | tmp.t_rprntc = tty->termios.c_cc[VREPRINT]; | |
355d95a1 | 594 | /* what is flushc anyway? */ |
adc8d746 AC |
595 | tmp.t_flushc = tty->termios.c_cc[VEOL2]; |
596 | tmp.t_werasc = tty->termios.c_cc[VWERASE]; | |
597 | tmp.t_lnextc = tty->termios.c_cc[VLNEXT]; | |
6a1c0680 | 598 | up_read(&tty->termios_rwsem); |
1da177e4 LT |
599 | return copy_to_user(ltchars, &tmp, sizeof(tmp)) ? -EFAULT : 0; |
600 | } | |
601 | ||
355d95a1 | 602 | static int set_ltchars(struct tty_struct *tty, struct ltchars __user *ltchars) |
1da177e4 LT |
603 | { |
604 | struct ltchars tmp; | |
605 | ||
606 | if (copy_from_user(&tmp, ltchars, sizeof(tmp))) | |
607 | return -EFAULT; | |
608 | ||
6a1c0680 | 609 | down_write(&tty->termios_rwsem); |
adc8d746 | 610 | tty->termios.c_cc[VSUSP] = tmp.t_suspc; |
355d95a1 | 611 | /* what is dsuspc anyway? */ |
adc8d746 AC |
612 | tty->termios.c_cc[VEOL2] = tmp.t_dsuspc; |
613 | tty->termios.c_cc[VREPRINT] = tmp.t_rprntc; | |
355d95a1 | 614 | /* what is flushc anyway? */ |
adc8d746 AC |
615 | tty->termios.c_cc[VEOL2] = tmp.t_flushc; |
616 | tty->termios.c_cc[VWERASE] = tmp.t_werasc; | |
617 | tty->termios.c_cc[VLNEXT] = tmp.t_lnextc; | |
6a1c0680 | 618 | up_write(&tty->termios_rwsem); |
1da177e4 LT |
619 | return 0; |
620 | } | |
621 | #endif | |
622 | ||
1c2630cc AC |
623 | /** |
624 | * tty_change_softcar - carrier change ioctl helper | |
625 | * @tty: tty to update | |
626 | * @arg: enable/disable CLOCAL | |
627 | * | |
628 | * Perform a change to the CLOCAL state and call into the driver | |
6a1c0680 | 629 | * layer to make it visible. All done with the termios rwsem |
1c2630cc AC |
630 | */ |
631 | ||
632 | static int tty_change_softcar(struct tty_struct *tty, int arg) | |
633 | { | |
634 | int ret = 0; | |
635 | int bit = arg ? CLOCAL : 0; | |
f34d7a5b | 636 | struct ktermios old; |
1c2630cc | 637 | |
6a1c0680 | 638 | down_write(&tty->termios_rwsem); |
adc8d746 AC |
639 | old = tty->termios; |
640 | tty->termios.c_cflag &= ~CLOCAL; | |
641 | tty->termios.c_cflag |= bit; | |
f34d7a5b AC |
642 | if (tty->ops->set_termios) |
643 | tty->ops->set_termios(tty, &old); | |
9db276f8 | 644 | if (C_CLOCAL(tty) != bit) |
1c2630cc | 645 | ret = -EINVAL; |
6a1c0680 | 646 | up_write(&tty->termios_rwsem); |
1c2630cc AC |
647 | return ret; |
648 | } | |
649 | ||
0fc00e24 AC |
650 | /** |
651 | * tty_mode_ioctl - mode related ioctls | |
652 | * @tty: tty for the ioctl | |
653 | * @file: file pointer for the tty | |
654 | * @cmd: command | |
655 | * @arg: ioctl argument | |
656 | * | |
657 | * Perform non line discipline specific mode control ioctls. This | |
658 | * is designed to be called by line disciplines to ensure they provide | |
659 | * consistent mode setting. | |
660 | */ | |
661 | ||
355d95a1 | 662 | int tty_mode_ioctl(struct tty_struct *tty, struct file *file, |
0fc00e24 | 663 | unsigned int cmd, unsigned long arg) |
1da177e4 | 664 | { |
355d95a1 | 665 | struct tty_struct *real_tty; |
1da177e4 | 666 | void __user *p = (void __user *)arg; |
8f520021 | 667 | int ret = 0; |
26a2e20f | 668 | struct ktermios kterm; |
1da177e4 | 669 | |
8d075b19 AC |
670 | BUG_ON(file == NULL); |
671 | ||
1da177e4 LT |
672 | if (tty->driver->type == TTY_DRIVER_TYPE_PTY && |
673 | tty->driver->subtype == PTY_TYPE_MASTER) | |
674 | real_tty = tty->link; | |
675 | else | |
676 | real_tty = tty; | |
677 | ||
678 | switch (cmd) { | |
679 | #ifdef TIOCGETP | |
355d95a1 AC |
680 | case TIOCGETP: |
681 | return get_sgttyb(real_tty, (struct sgttyb __user *) arg); | |
682 | case TIOCSETP: | |
683 | case TIOCSETN: | |
684 | return set_sgttyb(real_tty, (struct sgttyb __user *) arg); | |
1da177e4 LT |
685 | #endif |
686 | #ifdef TIOCGETC | |
355d95a1 AC |
687 | case TIOCGETC: |
688 | return get_tchars(real_tty, p); | |
689 | case TIOCSETC: | |
690 | return set_tchars(real_tty, p); | |
1da177e4 LT |
691 | #endif |
692 | #ifdef TIOCGLTC | |
355d95a1 AC |
693 | case TIOCGLTC: |
694 | return get_ltchars(real_tty, p); | |
695 | case TIOCSLTC: | |
696 | return set_ltchars(real_tty, p); | |
1da177e4 | 697 | #endif |
355d95a1 AC |
698 | case TCSETSF: |
699 | return set_termios(real_tty, p, TERMIOS_FLUSH | TERMIOS_WAIT | TERMIOS_OLD); | |
700 | case TCSETSW: | |
701 | return set_termios(real_tty, p, TERMIOS_WAIT | TERMIOS_OLD); | |
702 | case TCSETS: | |
703 | return set_termios(real_tty, p, TERMIOS_OLD); | |
edc6afc5 | 704 | #ifndef TCGETS2 |
355d95a1 | 705 | case TCGETS: |
26a2e20f AC |
706 | copy_termios(real_tty, &kterm); |
707 | if (kernel_termios_to_user_termios((struct termios __user *)arg, &kterm)) | |
8f520021 | 708 | ret = -EFAULT; |
8f520021 | 709 | return ret; |
edc6afc5 | 710 | #else |
355d95a1 | 711 | case TCGETS: |
26a2e20f AC |
712 | copy_termios(real_tty, &kterm); |
713 | if (kernel_termios_to_user_termios_1((struct termios __user *)arg, &kterm)) | |
8f520021 | 714 | ret = -EFAULT; |
8f520021 | 715 | return ret; |
355d95a1 | 716 | case TCGETS2: |
26a2e20f AC |
717 | copy_termios(real_tty, &kterm); |
718 | if (kernel_termios_to_user_termios((struct termios2 __user *)arg, &kterm)) | |
8f520021 | 719 | ret = -EFAULT; |
8f520021 | 720 | return ret; |
355d95a1 AC |
721 | case TCSETSF2: |
722 | return set_termios(real_tty, p, TERMIOS_FLUSH | TERMIOS_WAIT); | |
723 | case TCSETSW2: | |
724 | return set_termios(real_tty, p, TERMIOS_WAIT); | |
725 | case TCSETS2: | |
726 | return set_termios(real_tty, p, 0); | |
edc6afc5 | 727 | #endif |
355d95a1 AC |
728 | case TCGETA: |
729 | return get_termio(real_tty, p); | |
730 | case TCSETAF: | |
731 | return set_termios(real_tty, p, TERMIOS_FLUSH | TERMIOS_WAIT | TERMIOS_TERMIO); | |
732 | case TCSETAW: | |
733 | return set_termios(real_tty, p, TERMIOS_WAIT | TERMIOS_TERMIO); | |
734 | case TCSETA: | |
735 | return set_termios(real_tty, p, TERMIOS_TERMIO); | |
0fc00e24 | 736 | #ifndef TCGETS2 |
355d95a1 | 737 | case TIOCGLCKTRMIOS: |
26a2e20f AC |
738 | copy_termios_locked(real_tty, &kterm); |
739 | if (kernel_termios_to_user_termios((struct termios __user *)arg, &kterm)) | |
8f520021 | 740 | ret = -EFAULT; |
8f520021 | 741 | return ret; |
355d95a1 AC |
742 | case TIOCSLCKTRMIOS: |
743 | if (!capable(CAP_SYS_ADMIN)) | |
744 | return -EPERM; | |
26a2e20f AC |
745 | copy_termios_locked(real_tty, &kterm); |
746 | if (user_termios_to_kernel_termios(&kterm, | |
355d95a1 | 747 | (struct termios __user *) arg)) |
26a2e20f | 748 | return -EFAULT; |
6a1c0680 | 749 | down_write(&real_tty->termios_rwsem); |
adc8d746 | 750 | real_tty->termios_locked = kterm; |
6a1c0680 | 751 | up_write(&real_tty->termios_rwsem); |
26a2e20f | 752 | return 0; |
0fc00e24 | 753 | #else |
355d95a1 | 754 | case TIOCGLCKTRMIOS: |
26a2e20f AC |
755 | copy_termios_locked(real_tty, &kterm); |
756 | if (kernel_termios_to_user_termios_1((struct termios __user *)arg, &kterm)) | |
8f520021 | 757 | ret = -EFAULT; |
8f520021 | 758 | return ret; |
355d95a1 AC |
759 | case TIOCSLCKTRMIOS: |
760 | if (!capable(CAP_SYS_ADMIN)) | |
26a2e20f AC |
761 | return -EPERM; |
762 | copy_termios_locked(real_tty, &kterm); | |
763 | if (user_termios_to_kernel_termios_1(&kterm, | |
355d95a1 | 764 | (struct termios __user *) arg)) |
26a2e20f | 765 | return -EFAULT; |
6a1c0680 | 766 | down_write(&real_tty->termios_rwsem); |
adc8d746 | 767 | real_tty->termios_locked = kterm; |
6a1c0680 | 768 | up_write(&real_tty->termios_rwsem); |
8f520021 | 769 | return ret; |
0fc00e24 | 770 | #endif |
1d65b4a0 | 771 | #ifdef TCGETX |
e0efb316 | 772 | case TCGETX: |
1d65b4a0 | 773 | case TCSETX: |
1d65b4a0 | 774 | case TCSETXW: |
1d65b4a0 | 775 | case TCSETXF: |
8871de06 JH |
776 | return -ENOTTY; |
777 | #endif | |
355d95a1 | 778 | case TIOCGSOFTCAR: |
26a2e20f AC |
779 | copy_termios(real_tty, &kterm); |
780 | ret = put_user((kterm.c_cflag & CLOCAL) ? 1 : 0, | |
355d95a1 | 781 | (int __user *)arg); |
8f520021 | 782 | return ret; |
355d95a1 AC |
783 | case TIOCSSOFTCAR: |
784 | if (get_user(arg, (unsigned int __user *) arg)) | |
785 | return -EFAULT; | |
f753f327 | 786 | return tty_change_softcar(real_tty, arg); |
355d95a1 AC |
787 | default: |
788 | return -ENOIOCTLCMD; | |
0fc00e24 AC |
789 | } |
790 | } | |
0fc00e24 AC |
791 | EXPORT_SYMBOL_GPL(tty_mode_ioctl); |
792 | ||
e7f3880c PH |
793 | |
794 | /* Caller guarantees ldisc reference is held */ | |
795 | static int __tty_perform_flush(struct tty_struct *tty, unsigned long arg) | |
0fc00e24 | 796 | { |
e7f3880c | 797 | struct tty_ldisc *ld = tty->ldisc; |
0fc00e24 | 798 | |
0fc00e24 AC |
799 | switch (arg) { |
800 | case TCIFLUSH: | |
a1bf9584 | 801 | if (ld && ld->ops->flush_buffer) { |
a352def2 | 802 | ld->ops->flush_buffer(tty); |
a1bf9584 IZ |
803 | tty_unthrottle(tty); |
804 | } | |
0fc00e24 AC |
805 | break; |
806 | case TCIOFLUSH: | |
a1bf9584 | 807 | if (ld && ld->ops->flush_buffer) { |
a352def2 | 808 | ld->ops->flush_buffer(tty); |
a1bf9584 IZ |
809 | tty_unthrottle(tty); |
810 | } | |
df561f66 | 811 | fallthrough; |
0fc00e24 | 812 | case TCOFLUSH: |
f34d7a5b | 813 | tty_driver_flush_buffer(tty); |
0fc00e24 AC |
814 | break; |
815 | default: | |
0fc00e24 AC |
816 | return -EINVAL; |
817 | } | |
0fc00e24 AC |
818 | return 0; |
819 | } | |
e7f3880c PH |
820 | |
821 | int tty_perform_flush(struct tty_struct *tty, unsigned long arg) | |
822 | { | |
823 | struct tty_ldisc *ld; | |
824 | int retval = tty_check_change(tty); | |
825 | if (retval) | |
826 | return retval; | |
827 | ||
828 | ld = tty_ldisc_ref_wait(tty); | |
829 | retval = __tty_perform_flush(tty, arg); | |
830 | if (ld) | |
831 | tty_ldisc_deref(ld); | |
832 | return retval; | |
833 | } | |
0fc00e24 AC |
834 | EXPORT_SYMBOL_GPL(tty_perform_flush); |
835 | ||
47afa7a5 | 836 | int n_tty_ioctl_helper(struct tty_struct *tty, struct file *file, |
0fc00e24 AC |
837 | unsigned int cmd, unsigned long arg) |
838 | { | |
0fc00e24 AC |
839 | int retval; |
840 | ||
0fc00e24 | 841 | switch (cmd) { |
355d95a1 AC |
842 | case TCXONC: |
843 | retval = tty_check_change(tty); | |
844 | if (retval) | |
845 | return retval; | |
846 | switch (arg) { | |
847 | case TCOOFF: | |
c545b66c | 848 | spin_lock_irq(&tty->flow_lock); |
355d95a1 AC |
849 | if (!tty->flow_stopped) { |
850 | tty->flow_stopped = 1; | |
c545b66c | 851 | __stop_tty(tty); |
1da177e4 | 852 | } |
c545b66c | 853 | spin_unlock_irq(&tty->flow_lock); |
355d95a1 AC |
854 | break; |
855 | case TCOON: | |
c545b66c | 856 | spin_lock_irq(&tty->flow_lock); |
355d95a1 AC |
857 | if (tty->flow_stopped) { |
858 | tty->flow_stopped = 0; | |
c545b66c | 859 | __start_tty(tty); |
355d95a1 | 860 | } |
c545b66c | 861 | spin_unlock_irq(&tty->flow_lock); |
355d95a1 AC |
862 | break; |
863 | case TCIOFF: | |
864 | if (STOP_CHAR(tty) != __DISABLED_CHAR) | |
c274f6ef | 865 | retval = tty_send_xchar(tty, STOP_CHAR(tty)); |
355d95a1 AC |
866 | break; |
867 | case TCION: | |
868 | if (START_CHAR(tty) != __DISABLED_CHAR) | |
c274f6ef | 869 | retval = tty_send_xchar(tty, START_CHAR(tty)); |
355d95a1 | 870 | break; |
1da177e4 | 871 | default: |
355d95a1 | 872 | return -EINVAL; |
1da177e4 | 873 | } |
c274f6ef | 874 | return retval; |
355d95a1 | 875 | case TCFLSH: |
5cec7bf6 PH |
876 | retval = tty_check_change(tty); |
877 | if (retval) | |
878 | return retval; | |
e7f3880c | 879 | return __tty_perform_flush(tty, arg); |
355d95a1 AC |
880 | default: |
881 | /* Try the mode commands */ | |
882 | return tty_mode_ioctl(tty, file, cmd, arg); | |
883 | } | |
1da177e4 | 884 | } |
47afa7a5 | 885 | EXPORT_SYMBOL(n_tty_ioctl_helper); |