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-rw-r--r--drivers/tty/tty_ioctl.c1179
1 files changed, 1179 insertions, 0 deletions
diff --git a/drivers/tty/tty_ioctl.c b/drivers/tty/tty_ioctl.c
new file mode 100644
index 000000000000..0c1889971459
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+++ b/drivers/tty/tty_ioctl.c
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1/*
2 * linux/drivers/char/tty_ioctl.c
3 *
4 * Copyright (C) 1991, 1992, 1993, 1994 Linus Torvalds
5 *
6 * Modified by Fred N. van Kempen, 01/29/93, to add line disciplines
7 * which can be dynamically activated and de-activated by the line
8 * discipline handling modules (like SLIP).
9 */
10
11#include <linux/types.h>
12#include <linux/termios.h>
13#include <linux/errno.h>
14#include <linux/sched.h>
15#include <linux/kernel.h>
16#include <linux/major.h>
17#include <linux/tty.h>
18#include <linux/fcntl.h>
19#include <linux/string.h>
20#include <linux/mm.h>
21#include <linux/module.h>
22#include <linux/bitops.h>
23#include <linux/mutex.h>
24
25#include <asm/io.h>
26#include <asm/uaccess.h>
27#include <asm/system.h>
28
29#undef TTY_DEBUG_WAIT_UNTIL_SENT
30
31#undef DEBUG
32
33/*
34 * Internal flag options for termios setting behavior
35 */
36#define TERMIOS_FLUSH 1
37#define TERMIOS_WAIT 2
38#define TERMIOS_TERMIO 4
39#define TERMIOS_OLD 8
40
41
42/**
43 * tty_chars_in_buffer - characters pending
44 * @tty: terminal
45 *
46 * Return the number of bytes of data in the device private
47 * output queue. If no private method is supplied there is assumed
48 * to be no queue on the device.
49 */
50
51int tty_chars_in_buffer(struct tty_struct *tty)
52{
53 if (tty->ops->chars_in_buffer)
54 return tty->ops->chars_in_buffer(tty);
55 else
56 return 0;
57}
58EXPORT_SYMBOL(tty_chars_in_buffer);
59
60/**
61 * tty_write_room - write queue space
62 * @tty: terminal
63 *
64 * Return the number of bytes that can be queued to this device
65 * at the present time. The result should be treated as a guarantee
66 * and the driver cannot offer a value it later shrinks by more than
67 * the number of bytes written. If no method is provided 2K is always
68 * returned and data may be lost as there will be no flow control.
69 */
70
71int tty_write_room(struct tty_struct *tty)
72{
73 if (tty->ops->write_room)
74 return tty->ops->write_room(tty);
75 return 2048;
76}
77EXPORT_SYMBOL(tty_write_room);
78
79/**
80 * tty_driver_flush_buffer - discard internal buffer
81 * @tty: terminal
82 *
83 * Discard the internal output buffer for this device. If no method
84 * is provided then either the buffer cannot be hardware flushed or
85 * there is no buffer driver side.
86 */
87void tty_driver_flush_buffer(struct tty_struct *tty)
88{
89 if (tty->ops->flush_buffer)
90 tty->ops->flush_buffer(tty);
91}
92EXPORT_SYMBOL(tty_driver_flush_buffer);
93
94/**
95 * tty_throttle - flow control
96 * @tty: terminal
97 *
98 * Indicate that a tty should stop transmitting data down the stack.
99 * Takes the termios mutex to protect against parallel throttle/unthrottle
100 * and also to ensure the driver can consistently reference its own
101 * termios data at this point when implementing software flow control.
102 */
103
104void tty_throttle(struct tty_struct *tty)
105{
106 mutex_lock(&tty->termios_mutex);
107 /* check TTY_THROTTLED first so it indicates our state */
108 if (!test_and_set_bit(TTY_THROTTLED, &tty->flags) &&
109 tty->ops->throttle)
110 tty->ops->throttle(tty);
111 mutex_unlock(&tty->termios_mutex);
112}
113EXPORT_SYMBOL(tty_throttle);
114
115/**
116 * tty_unthrottle - flow control
117 * @tty: terminal
118 *
119 * Indicate that a tty may continue transmitting data down the stack.
120 * Takes the termios mutex to protect against parallel throttle/unthrottle
121 * and also to ensure the driver can consistently reference its own
122 * termios data at this point when implementing software flow control.
123 *
124 * Drivers should however remember that the stack can issue a throttle,
125 * then change flow control method, then unthrottle.
126 */
127
128void tty_unthrottle(struct tty_struct *tty)
129{
130 mutex_lock(&tty->termios_mutex);
131 if (test_and_clear_bit(TTY_THROTTLED, &tty->flags) &&
132 tty->ops->unthrottle)
133 tty->ops->unthrottle(tty);
134 mutex_unlock(&tty->termios_mutex);
135}
136EXPORT_SYMBOL(tty_unthrottle);
137
138/**
139 * tty_wait_until_sent - wait for I/O to finish
140 * @tty: tty we are waiting for
141 * @timeout: how long we will wait
142 *
143 * Wait for characters pending in a tty driver to hit the wire, or
144 * for a timeout to occur (eg due to flow control)
145 *
146 * Locking: none
147 */
148
149void tty_wait_until_sent(struct tty_struct *tty, long timeout)
150{
151#ifdef TTY_DEBUG_WAIT_UNTIL_SENT
152 char buf[64];
153
154 printk(KERN_DEBUG "%s wait until sent...\n", tty_name(tty, buf));
155#endif
156 if (!timeout)
157 timeout = MAX_SCHEDULE_TIMEOUT;
158 if (wait_event_interruptible_timeout(tty->write_wait,
159 !tty_chars_in_buffer(tty), timeout) >= 0) {
160 if (tty->ops->wait_until_sent)
161 tty->ops->wait_until_sent(tty, timeout);
162 }
163}
164EXPORT_SYMBOL(tty_wait_until_sent);
165
166
167/*
168 * Termios Helper Methods
169 */
170
171static void unset_locked_termios(struct ktermios *termios,
172 struct ktermios *old,
173 struct ktermios *locked)
174{
175 int i;
176
177#define NOSET_MASK(x, y, z) (x = ((x) & ~(z)) | ((y) & (z)))
178
179 if (!locked) {
180 printk(KERN_WARNING "Warning?!? termios_locked is NULL.\n");
181 return;
182 }
183
184 NOSET_MASK(termios->c_iflag, old->c_iflag, locked->c_iflag);
185 NOSET_MASK(termios->c_oflag, old->c_oflag, locked->c_oflag);
186 NOSET_MASK(termios->c_cflag, old->c_cflag, locked->c_cflag);
187 NOSET_MASK(termios->c_lflag, old->c_lflag, locked->c_lflag);
188 termios->c_line = locked->c_line ? old->c_line : termios->c_line;
189 for (i = 0; i < NCCS; i++)
190 termios->c_cc[i] = locked->c_cc[i] ?
191 old->c_cc[i] : termios->c_cc[i];
192 /* FIXME: What should we do for i/ospeed */
193}
194
195/*
196 * Routine which returns the baud rate of the tty
197 *
198 * Note that the baud_table needs to be kept in sync with the
199 * include/asm/termbits.h file.
200 */
201static const speed_t baud_table[] = {
202 0, 50, 75, 110, 134, 150, 200, 300, 600, 1200, 1800, 2400, 4800,
203 9600, 19200, 38400, 57600, 115200, 230400, 460800,
204#ifdef __sparc__
205 76800, 153600, 307200, 614400, 921600
206#else
207 500000, 576000, 921600, 1000000, 1152000, 1500000, 2000000,
208 2500000, 3000000, 3500000, 4000000
209#endif
210};
211
212#ifndef __sparc__
213static const tcflag_t baud_bits[] = {
214 B0, B50, B75, B110, B134, B150, B200, B300, B600,
215 B1200, B1800, B2400, B4800, B9600, B19200, B38400,
216 B57600, B115200, B230400, B460800, B500000, B576000,
217 B921600, B1000000, B1152000, B1500000, B2000000, B2500000,
218 B3000000, B3500000, B4000000
219};
220#else
221static const tcflag_t baud_bits[] = {
222 B0, B50, B75, B110, B134, B150, B200, B300, B600,
223 B1200, B1800, B2400, B4800, B9600, B19200, B38400,
224 B57600, B115200, B230400, B460800, B76800, B153600,
225 B307200, B614400, B921600
226};
227#endif
228
229static int n_baud_table = ARRAY_SIZE(baud_table);
230
231/**
232 * tty_termios_baud_rate
233 * @termios: termios structure
234 *
235 * Convert termios baud rate data into a speed. This should be called
236 * with the termios lock held if this termios is a terminal termios
237 * structure. May change the termios data. Device drivers can call this
238 * function but should use ->c_[io]speed directly as they are updated.
239 *
240 * Locking: none
241 */
242
243speed_t tty_termios_baud_rate(struct ktermios *termios)
244{
245 unsigned int cbaud;
246
247 cbaud = termios->c_cflag & CBAUD;
248
249#ifdef BOTHER
250 /* Magic token for arbitary speed via c_ispeed/c_ospeed */
251 if (cbaud == BOTHER)
252 return termios->c_ospeed;
253#endif
254 if (cbaud & CBAUDEX) {
255 cbaud &= ~CBAUDEX;
256
257 if (cbaud < 1 || cbaud + 15 > n_baud_table)
258 termios->c_cflag &= ~CBAUDEX;
259 else
260 cbaud += 15;
261 }
262 return baud_table[cbaud];
263}
264EXPORT_SYMBOL(tty_termios_baud_rate);
265
266/**
267 * tty_termios_input_baud_rate
268 * @termios: termios structure
269 *
270 * Convert termios baud rate data into a speed. This should be called
271 * with the termios lock held if this termios is a terminal termios
272 * structure. May change the termios data. Device drivers can call this
273 * function but should use ->c_[io]speed directly as they are updated.
274 *
275 * Locking: none
276 */
277
278speed_t tty_termios_input_baud_rate(struct ktermios *termios)
279{
280#ifdef IBSHIFT
281 unsigned int cbaud = (termios->c_cflag >> IBSHIFT) & CBAUD;
282
283 if (cbaud == B0)
284 return tty_termios_baud_rate(termios);
285
286 /* Magic token for arbitary speed via c_ispeed*/
287 if (cbaud == BOTHER)
288 return termios->c_ispeed;
289
290 if (cbaud & CBAUDEX) {
291 cbaud &= ~CBAUDEX;
292
293 if (cbaud < 1 || cbaud + 15 > n_baud_table)
294 termios->c_cflag &= ~(CBAUDEX << IBSHIFT);
295 else
296 cbaud += 15;
297 }
298 return baud_table[cbaud];
299#else
300 return tty_termios_baud_rate(termios);
301#endif
302}
303EXPORT_SYMBOL(tty_termios_input_baud_rate);
304
305/**
306 * tty_termios_encode_baud_rate
307 * @termios: ktermios structure holding user requested state
308 * @ispeed: input speed
309 * @ospeed: output speed
310 *
311 * Encode the speeds set into the passed termios structure. This is
312 * used as a library helper for drivers os that they can report back
313 * the actual speed selected when it differs from the speed requested
314 *
315 * For maximal back compatibility with legacy SYS5/POSIX *nix behaviour
316 * we need to carefully set the bits when the user does not get the
317 * desired speed. We allow small margins and preserve as much of possible
318 * of the input intent to keep compatibility.
319 *
320 * Locking: Caller should hold termios lock. This is already held
321 * when calling this function from the driver termios handler.
322 *
323 * The ifdefs deal with platforms whose owners have yet to update them
324 * and will all go away once this is done.
325 */
326
327void tty_termios_encode_baud_rate(struct ktermios *termios,
328 speed_t ibaud, speed_t obaud)
329{
330 int i = 0;
331 int ifound = -1, ofound = -1;
332 int iclose = ibaud/50, oclose = obaud/50;
333 int ibinput = 0;
334
335 if (obaud == 0) /* CD dropped */
336 ibaud = 0; /* Clear ibaud to be sure */
337
338 termios->c_ispeed = ibaud;
339 termios->c_ospeed = obaud;
340
341#ifdef BOTHER
342 /* If the user asked for a precise weird speed give a precise weird
343 answer. If they asked for a Bfoo speed they many have problems
344 digesting non-exact replies so fuzz a bit */
345
346 if ((termios->c_cflag & CBAUD) == BOTHER)
347 oclose = 0;
348 if (((termios->c_cflag >> IBSHIFT) & CBAUD) == BOTHER)
349 iclose = 0;
350 if ((termios->c_cflag >> IBSHIFT) & CBAUD)
351 ibinput = 1; /* An input speed was specified */
352#endif
353 termios->c_cflag &= ~CBAUD;
354
355 /*
356 * Our goal is to find a close match to the standard baud rate
357 * returned. Walk the baud rate table and if we get a very close
358 * match then report back the speed as a POSIX Bxxxx value by
359 * preference
360 */
361
362 do {
363 if (obaud - oclose <= baud_table[i] &&
364 obaud + oclose >= baud_table[i]) {
365 termios->c_cflag |= baud_bits[i];
366 ofound = i;
367 }
368 if (ibaud - iclose <= baud_table[i] &&
369 ibaud + iclose >= baud_table[i]) {
370 /* For the case input == output don't set IBAUD bits
371 if the user didn't do so */
372 if (ofound == i && !ibinput)
373 ifound = i;
374#ifdef IBSHIFT
375 else {
376 ifound = i;
377 termios->c_cflag |= (baud_bits[i] << IBSHIFT);
378 }
379#endif
380 }
381 } while (++i < n_baud_table);
382
383 /*
384 * If we found no match then use BOTHER if provided or warn
385 * the user their platform maintainer needs to wake up if not.
386 */
387#ifdef BOTHER
388 if (ofound == -1)
389 termios->c_cflag |= BOTHER;
390 /* Set exact input bits only if the input and output differ or the
391 user already did */
392 if (ifound == -1 && (ibaud != obaud || ibinput))
393 termios->c_cflag |= (BOTHER << IBSHIFT);
394#else
395 if (ifound == -1 || ofound == -1) {
396 printk_once(KERN_WARNING "tty: Unable to return correct "
397 "speed data as your architecture needs updating.\n");
398 }
399#endif
400}
401EXPORT_SYMBOL_GPL(tty_termios_encode_baud_rate);
402
403/**
404 * tty_encode_baud_rate - set baud rate of the tty
405 * @ibaud: input baud rate
406 * @obad: output baud rate
407 *
408 * Update the current termios data for the tty with the new speed
409 * settings. The caller must hold the termios_mutex for the tty in
410 * question.
411 */
412
413void tty_encode_baud_rate(struct tty_struct *tty, speed_t ibaud, speed_t obaud)
414{
415 tty_termios_encode_baud_rate(tty->termios, ibaud, obaud);
416}
417EXPORT_SYMBOL_GPL(tty_encode_baud_rate);
418
419/**
420 * tty_get_baud_rate - get tty bit rates
421 * @tty: tty to query
422 *
423 * Returns the baud rate as an integer for this terminal. The
424 * termios lock must be held by the caller and the terminal bit
425 * flags may be updated.
426 *
427 * Locking: none
428 */
429
430speed_t tty_get_baud_rate(struct tty_struct *tty)
431{
432 speed_t baud = tty_termios_baud_rate(tty->termios);
433
434 if (baud == 38400 && tty->alt_speed) {
435 if (!tty->warned) {
436 printk(KERN_WARNING "Use of setserial/setrocket to "
437 "set SPD_* flags is deprecated\n");
438 tty->warned = 1;
439 }
440 baud = tty->alt_speed;
441 }
442
443 return baud;
444}
445EXPORT_SYMBOL(tty_get_baud_rate);
446
447/**
448 * tty_termios_copy_hw - copy hardware settings
449 * @new: New termios
450 * @old: Old termios
451 *
452 * Propogate the hardware specific terminal setting bits from
453 * the old termios structure to the new one. This is used in cases
454 * where the hardware does not support reconfiguration or as a helper
455 * in some cases where only minimal reconfiguration is supported
456 */
457
458void tty_termios_copy_hw(struct ktermios *new, struct ktermios *old)
459{
460 /* The bits a dumb device handles in software. Smart devices need
461 to always provide a set_termios method */
462 new->c_cflag &= HUPCL | CREAD | CLOCAL;
463 new->c_cflag |= old->c_cflag & ~(HUPCL | CREAD | CLOCAL);
464 new->c_ispeed = old->c_ispeed;
465 new->c_ospeed = old->c_ospeed;
466}
467EXPORT_SYMBOL(tty_termios_copy_hw);
468
469/**
470 * tty_termios_hw_change - check for setting change
471 * @a: termios
472 * @b: termios to compare
473 *
474 * Check if any of the bits that affect a dumb device have changed
475 * between the two termios structures, or a speed change is needed.
476 */
477
478int tty_termios_hw_change(struct ktermios *a, struct ktermios *b)
479{
480 if (a->c_ispeed != b->c_ispeed || a->c_ospeed != b->c_ospeed)
481 return 1;
482 if ((a->c_cflag ^ b->c_cflag) & ~(HUPCL | CREAD | CLOCAL))
483 return 1;
484 return 0;
485}
486EXPORT_SYMBOL(tty_termios_hw_change);
487
488/**
489 * change_termios - update termios values
490 * @tty: tty to update
491 * @new_termios: desired new value
492 *
493 * Perform updates to the termios values set on this terminal. There
494 * is a bit of layering violation here with n_tty in terms of the
495 * internal knowledge of this function.
496 *
497 * Locking: termios_mutex
498 */
499
500static void change_termios(struct tty_struct *tty, struct ktermios *new_termios)
501{
502 struct ktermios old_termios;
503 struct tty_ldisc *ld;
504 unsigned long flags;
505
506 /*
507 * Perform the actual termios internal changes under lock.
508 */
509
510
511 /* FIXME: we need to decide on some locking/ordering semantics
512 for the set_termios notification eventually */
513 mutex_lock(&tty->termios_mutex);
514 old_termios = *tty->termios;
515 *tty->termios = *new_termios;
516 unset_locked_termios(tty->termios, &old_termios, tty->termios_locked);
517
518 /* See if packet mode change of state. */
519 if (tty->link && tty->link->packet) {
520 int extproc = (old_termios.c_lflag & EXTPROC) |
521 (tty->termios->c_lflag & EXTPROC);
522 int old_flow = ((old_termios.c_iflag & IXON) &&
523 (old_termios.c_cc[VSTOP] == '\023') &&
524 (old_termios.c_cc[VSTART] == '\021'));
525 int new_flow = (I_IXON(tty) &&
526 STOP_CHAR(tty) == '\023' &&
527 START_CHAR(tty) == '\021');
528 if ((old_flow != new_flow) || extproc) {
529 spin_lock_irqsave(&tty->ctrl_lock, flags);
530 if (old_flow != new_flow) {
531 tty->ctrl_status &= ~(TIOCPKT_DOSTOP | TIOCPKT_NOSTOP);
532 if (new_flow)
533 tty->ctrl_status |= TIOCPKT_DOSTOP;
534 else
535 tty->ctrl_status |= TIOCPKT_NOSTOP;
536 }
537 if (extproc)
538 tty->ctrl_status |= TIOCPKT_IOCTL;
539 spin_unlock_irqrestore(&tty->ctrl_lock, flags);
540 wake_up_interruptible(&tty->link->read_wait);
541 }
542 }
543
544 if (tty->ops->set_termios)
545 (*tty->ops->set_termios)(tty, &old_termios);
546 else
547 tty_termios_copy_hw(tty->termios, &old_termios);
548
549 ld = tty_ldisc_ref(tty);
550 if (ld != NULL) {
551 if (ld->ops->set_termios)
552 (ld->ops->set_termios)(tty, &old_termios);
553 tty_ldisc_deref(ld);
554 }
555 mutex_unlock(&tty->termios_mutex);
556}
557
558/**
559 * set_termios - set termios values for a tty
560 * @tty: terminal device
561 * @arg: user data
562 * @opt: option information
563 *
564 * Helper function to prepare termios data and run necessary other
565 * functions before using change_termios to do the actual changes.
566 *
567 * Locking:
568 * Called functions take ldisc and termios_mutex locks
569 */
570
571static int set_termios(struct tty_struct *tty, void __user *arg, int opt)
572{
573 struct ktermios tmp_termios;
574 struct tty_ldisc *ld;
575 int retval = tty_check_change(tty);
576
577 if (retval)
578 return retval;
579
580 mutex_lock(&tty->termios_mutex);
581 memcpy(&tmp_termios, tty->termios, sizeof(struct ktermios));
582 mutex_unlock(&tty->termios_mutex);
583
584 if (opt & TERMIOS_TERMIO) {
585 if (user_termio_to_kernel_termios(&tmp_termios,
586 (struct termio __user *)arg))
587 return -EFAULT;
588#ifdef TCGETS2
589 } else if (opt & TERMIOS_OLD) {
590 if (user_termios_to_kernel_termios_1(&tmp_termios,
591 (struct termios __user *)arg))
592 return -EFAULT;
593 } else {
594 if (user_termios_to_kernel_termios(&tmp_termios,
595 (struct termios2 __user *)arg))
596 return -EFAULT;
597 }
598#else
599 } else if (user_termios_to_kernel_termios(&tmp_termios,
600 (struct termios __user *)arg))
601 return -EFAULT;
602#endif
603
604 /* If old style Bfoo values are used then load c_ispeed/c_ospeed
605 * with the real speed so its unconditionally usable */
606 tmp_termios.c_ispeed = tty_termios_input_baud_rate(&tmp_termios);
607 tmp_termios.c_ospeed = tty_termios_baud_rate(&tmp_termios);
608
609 ld = tty_ldisc_ref(tty);
610
611 if (ld != NULL) {
612 if ((opt & TERMIOS_FLUSH) && ld->ops->flush_buffer)
613 ld->ops->flush_buffer(tty);
614 tty_ldisc_deref(ld);
615 }
616
617 if (opt & TERMIOS_WAIT) {
618 tty_wait_until_sent(tty, 0);
619 if (signal_pending(current))
620 return -EINTR;
621 }
622
623 change_termios(tty, &tmp_termios);
624
625 /* FIXME: Arguably if tmp_termios == tty->termios AND the
626 actual requested termios was not tmp_termios then we may
627 want to return an error as no user requested change has
628 succeeded */
629 return 0;
630}
631
632static void copy_termios(struct tty_struct *tty, struct ktermios *kterm)
633{
634 mutex_lock(&tty->termios_mutex);
635 memcpy(kterm, tty->termios, sizeof(struct ktermios));
636 mutex_unlock(&tty->termios_mutex);
637}
638
639static void copy_termios_locked(struct tty_struct *tty, struct ktermios *kterm)
640{
641 mutex_lock(&tty->termios_mutex);
642 memcpy(kterm, tty->termios_locked, sizeof(struct ktermios));
643 mutex_unlock(&tty->termios_mutex);
644}
645
646static int get_termio(struct tty_struct *tty, struct termio __user *termio)
647{
648 struct ktermios kterm;
649 copy_termios(tty, &kterm);
650 if (kernel_termios_to_user_termio(termio, &kterm))
651 return -EFAULT;
652 return 0;
653}
654
655
656#ifdef TCGETX
657
658/**
659 * set_termiox - set termiox fields if possible
660 * @tty: terminal
661 * @arg: termiox structure from user
662 * @opt: option flags for ioctl type
663 *
664 * Implement the device calling points for the SYS5 termiox ioctl
665 * interface in Linux
666 */
667
668static int set_termiox(struct tty_struct *tty, void __user *arg, int opt)
669{
670 struct termiox tnew;
671 struct tty_ldisc *ld;
672
673 if (tty->termiox == NULL)
674 return -EINVAL;
675 if (copy_from_user(&tnew, arg, sizeof(struct termiox)))
676 return -EFAULT;
677
678 ld = tty_ldisc_ref(tty);
679 if (ld != NULL) {
680 if ((opt & TERMIOS_FLUSH) && ld->ops->flush_buffer)
681 ld->ops->flush_buffer(tty);
682 tty_ldisc_deref(ld);
683 }
684 if (opt & TERMIOS_WAIT) {
685 tty_wait_until_sent(tty, 0);
686 if (signal_pending(current))
687 return -EINTR;
688 }
689
690 mutex_lock(&tty->termios_mutex);
691 if (tty->ops->set_termiox)
692 tty->ops->set_termiox(tty, &tnew);
693 mutex_unlock(&tty->termios_mutex);
694 return 0;
695}
696
697#endif
698
699
700#ifdef TIOCGETP
701/*
702 * These are deprecated, but there is limited support..
703 *
704 * The "sg_flags" translation is a joke..
705 */
706static int get_sgflags(struct tty_struct *tty)
707{
708 int flags = 0;
709
710 if (!(tty->termios->c_lflag & ICANON)) {
711 if (tty->termios->c_lflag & ISIG)
712 flags |= 0x02; /* cbreak */
713 else
714 flags |= 0x20; /* raw */
715 }
716 if (tty->termios->c_lflag & ECHO)
717 flags |= 0x08; /* echo */
718 if (tty->termios->c_oflag & OPOST)
719 if (tty->termios->c_oflag & ONLCR)
720 flags |= 0x10; /* crmod */
721 return flags;
722}
723
724static int get_sgttyb(struct tty_struct *tty, struct sgttyb __user *sgttyb)
725{
726 struct sgttyb tmp;
727
728 mutex_lock(&tty->termios_mutex);
729 tmp.sg_ispeed = tty->termios->c_ispeed;
730 tmp.sg_ospeed = tty->termios->c_ospeed;
731 tmp.sg_erase = tty->termios->c_cc[VERASE];
732 tmp.sg_kill = tty->termios->c_cc[VKILL];
733 tmp.sg_flags = get_sgflags(tty);
734 mutex_unlock(&tty->termios_mutex);
735
736 return copy_to_user(sgttyb, &tmp, sizeof(tmp)) ? -EFAULT : 0;
737}
738
739static void set_sgflags(struct ktermios *termios, int flags)
740{
741 termios->c_iflag = ICRNL | IXON;
742 termios->c_oflag = 0;
743 termios->c_lflag = ISIG | ICANON;
744 if (flags & 0x02) { /* cbreak */
745 termios->c_iflag = 0;
746 termios->c_lflag &= ~ICANON;
747 }
748 if (flags & 0x08) { /* echo */
749 termios->c_lflag |= ECHO | ECHOE | ECHOK |
750 ECHOCTL | ECHOKE | IEXTEN;
751 }
752 if (flags & 0x10) { /* crmod */
753 termios->c_oflag |= OPOST | ONLCR;
754 }
755 if (flags & 0x20) { /* raw */
756 termios->c_iflag = 0;
757 termios->c_lflag &= ~(ISIG | ICANON);
758 }
759 if (!(termios->c_lflag & ICANON)) {
760 termios->c_cc[VMIN] = 1;
761 termios->c_cc[VTIME] = 0;
762 }
763}
764
765/**
766 * set_sgttyb - set legacy terminal values
767 * @tty: tty structure
768 * @sgttyb: pointer to old style terminal structure
769 *
770 * Updates a terminal from the legacy BSD style terminal information
771 * structure.
772 *
773 * Locking: termios_mutex
774 */
775
776static int set_sgttyb(struct tty_struct *tty, struct sgttyb __user *sgttyb)
777{
778 int retval;
779 struct sgttyb tmp;
780 struct ktermios termios;
781
782 retval = tty_check_change(tty);
783 if (retval)
784 return retval;
785
786 if (copy_from_user(&tmp, sgttyb, sizeof(tmp)))
787 return -EFAULT;
788
789 mutex_lock(&tty->termios_mutex);
790 termios = *tty->termios;
791 termios.c_cc[VERASE] = tmp.sg_erase;
792 termios.c_cc[VKILL] = tmp.sg_kill;
793 set_sgflags(&termios, tmp.sg_flags);
794 /* Try and encode into Bfoo format */
795#ifdef BOTHER
796 tty_termios_encode_baud_rate(&termios, termios.c_ispeed,
797 termios.c_ospeed);
798#endif
799 mutex_unlock(&tty->termios_mutex);
800 change_termios(tty, &termios);
801 return 0;
802}
803#endif
804
805#ifdef TIOCGETC
806static int get_tchars(struct tty_struct *tty, struct tchars __user *tchars)
807{
808 struct tchars tmp;
809
810 mutex_lock(&tty->termios_mutex);
811 tmp.t_intrc = tty->termios->c_cc[VINTR];
812 tmp.t_quitc = tty->termios->c_cc[VQUIT];
813 tmp.t_startc = tty->termios->c_cc[VSTART];
814 tmp.t_stopc = tty->termios->c_cc[VSTOP];
815 tmp.t_eofc = tty->termios->c_cc[VEOF];
816 tmp.t_brkc = tty->termios->c_cc[VEOL2]; /* what is brkc anyway? */
817 mutex_unlock(&tty->termios_mutex);
818 return copy_to_user(tchars, &tmp, sizeof(tmp)) ? -EFAULT : 0;
819}
820
821static int set_tchars(struct tty_struct *tty, struct tchars __user *tchars)
822{
823 struct tchars tmp;
824
825 if (copy_from_user(&tmp, tchars, sizeof(tmp)))
826 return -EFAULT;
827 mutex_lock(&tty->termios_mutex);
828 tty->termios->c_cc[VINTR] = tmp.t_intrc;
829 tty->termios->c_cc[VQUIT] = tmp.t_quitc;
830 tty->termios->c_cc[VSTART] = tmp.t_startc;
831 tty->termios->c_cc[VSTOP] = tmp.t_stopc;
832 tty->termios->c_cc[VEOF] = tmp.t_eofc;
833 tty->termios->c_cc[VEOL2] = tmp.t_brkc; /* what is brkc anyway? */
834 mutex_unlock(&tty->termios_mutex);
835 return 0;
836}
837#endif
838
839#ifdef TIOCGLTC
840static int get_ltchars(struct tty_struct *tty, struct ltchars __user *ltchars)
841{
842 struct ltchars tmp;
843
844 mutex_lock(&tty->termios_mutex);
845 tmp.t_suspc = tty->termios->c_cc[VSUSP];
846 /* what is dsuspc anyway? */
847 tmp.t_dsuspc = tty->termios->c_cc[VSUSP];
848 tmp.t_rprntc = tty->termios->c_cc[VREPRINT];
849 /* what is flushc anyway? */
850 tmp.t_flushc = tty->termios->c_cc[VEOL2];
851 tmp.t_werasc = tty->termios->c_cc[VWERASE];
852 tmp.t_lnextc = tty->termios->c_cc[VLNEXT];
853 mutex_unlock(&tty->termios_mutex);
854 return copy_to_user(ltchars, &tmp, sizeof(tmp)) ? -EFAULT : 0;
855}
856
857static int set_ltchars(struct tty_struct *tty, struct ltchars __user *ltchars)
858{
859 struct ltchars tmp;
860
861 if (copy_from_user(&tmp, ltchars, sizeof(tmp)))
862 return -EFAULT;
863
864 mutex_lock(&tty->termios_mutex);
865 tty->termios->c_cc[VSUSP] = tmp.t_suspc;
866 /* what is dsuspc anyway? */
867 tty->termios->c_cc[VEOL2] = tmp.t_dsuspc;
868 tty->termios->c_cc[VREPRINT] = tmp.t_rprntc;
869 /* what is flushc anyway? */
870 tty->termios->c_cc[VEOL2] = tmp.t_flushc;
871 tty->termios->c_cc[VWERASE] = tmp.t_werasc;
872 tty->termios->c_cc[VLNEXT] = tmp.t_lnextc;
873 mutex_unlock(&tty->termios_mutex);
874 return 0;
875}
876#endif
877
878/**
879 * send_prio_char - send priority character
880 *
881 * Send a high priority character to the tty even if stopped
882 *
883 * Locking: none for xchar method, write ordering for write method.
884 */
885
886static int send_prio_char(struct tty_struct *tty, char ch)
887{
888 int was_stopped = tty->stopped;
889
890 if (tty->ops->send_xchar) {
891 tty->ops->send_xchar(tty, ch);
892 return 0;
893 }
894
895 if (tty_write_lock(tty, 0) < 0)
896 return -ERESTARTSYS;
897
898 if (was_stopped)
899 start_tty(tty);
900 tty->ops->write(tty, &ch, 1);
901 if (was_stopped)
902 stop_tty(tty);
903 tty_write_unlock(tty);
904 return 0;
905}
906
907/**
908 * tty_change_softcar - carrier change ioctl helper
909 * @tty: tty to update
910 * @arg: enable/disable CLOCAL
911 *
912 * Perform a change to the CLOCAL state and call into the driver
913 * layer to make it visible. All done with the termios mutex
914 */
915
916static int tty_change_softcar(struct tty_struct *tty, int arg)
917{
918 int ret = 0;
919 int bit = arg ? CLOCAL : 0;
920 struct ktermios old;
921
922 mutex_lock(&tty->termios_mutex);
923 old = *tty->termios;
924 tty->termios->c_cflag &= ~CLOCAL;
925 tty->termios->c_cflag |= bit;
926 if (tty->ops->set_termios)
927 tty->ops->set_termios(tty, &old);
928 if ((tty->termios->c_cflag & CLOCAL) != bit)
929 ret = -EINVAL;
930 mutex_unlock(&tty->termios_mutex);
931 return ret;
932}
933
934/**
935 * tty_mode_ioctl - mode related ioctls
936 * @tty: tty for the ioctl
937 * @file: file pointer for the tty
938 * @cmd: command
939 * @arg: ioctl argument
940 *
941 * Perform non line discipline specific mode control ioctls. This
942 * is designed to be called by line disciplines to ensure they provide
943 * consistent mode setting.
944 */
945
946int tty_mode_ioctl(struct tty_struct *tty, struct file *file,
947 unsigned int cmd, unsigned long arg)
948{
949 struct tty_struct *real_tty;
950 void __user *p = (void __user *)arg;
951 int ret = 0;
952 struct ktermios kterm;
953
954 if (tty->driver->type == TTY_DRIVER_TYPE_PTY &&
955 tty->driver->subtype == PTY_TYPE_MASTER)
956 real_tty = tty->link;
957 else
958 real_tty = tty;
959
960 switch (cmd) {
961#ifdef TIOCGETP
962 case TIOCGETP:
963 return get_sgttyb(real_tty, (struct sgttyb __user *) arg);
964 case TIOCSETP:
965 case TIOCSETN:
966 return set_sgttyb(real_tty, (struct sgttyb __user *) arg);
967#endif
968#ifdef TIOCGETC
969 case TIOCGETC:
970 return get_tchars(real_tty, p);
971 case TIOCSETC:
972 return set_tchars(real_tty, p);
973#endif
974#ifdef TIOCGLTC
975 case TIOCGLTC:
976 return get_ltchars(real_tty, p);
977 case TIOCSLTC:
978 return set_ltchars(real_tty, p);
979#endif
980 case TCSETSF:
981 return set_termios(real_tty, p, TERMIOS_FLUSH | TERMIOS_WAIT | TERMIOS_OLD);
982 case TCSETSW:
983 return set_termios(real_tty, p, TERMIOS_WAIT | TERMIOS_OLD);
984 case TCSETS:
985 return set_termios(real_tty, p, TERMIOS_OLD);
986#ifndef TCGETS2
987 case TCGETS:
988 copy_termios(real_tty, &kterm);
989 if (kernel_termios_to_user_termios((struct termios __user *)arg, &kterm))
990 ret = -EFAULT;
991 return ret;
992#else
993 case TCGETS:
994 copy_termios(real_tty, &kterm);
995 if (kernel_termios_to_user_termios_1((struct termios __user *)arg, &kterm))
996 ret = -EFAULT;
997 return ret;
998 case TCGETS2:
999 copy_termios(real_tty, &kterm);
1000 if (kernel_termios_to_user_termios((struct termios2 __user *)arg, &kterm))
1001 ret = -EFAULT;
1002 return ret;
1003 case TCSETSF2:
1004 return set_termios(real_tty, p, TERMIOS_FLUSH | TERMIOS_WAIT);
1005 case TCSETSW2:
1006 return set_termios(real_tty, p, TERMIOS_WAIT);
1007 case TCSETS2:
1008 return set_termios(real_tty, p, 0);
1009#endif
1010 case TCGETA:
1011 return get_termio(real_tty, p);
1012 case TCSETAF:
1013 return set_termios(real_tty, p, TERMIOS_FLUSH | TERMIOS_WAIT | TERMIOS_TERMIO);
1014 case TCSETAW:
1015 return set_termios(real_tty, p, TERMIOS_WAIT | TERMIOS_TERMIO);
1016 case TCSETA:
1017 return set_termios(real_tty, p, TERMIOS_TERMIO);
1018#ifndef TCGETS2
1019 case TIOCGLCKTRMIOS:
1020 copy_termios_locked(real_tty, &kterm);
1021 if (kernel_termios_to_user_termios((struct termios __user *)arg, &kterm))
1022 ret = -EFAULT;
1023 return ret;
1024 case TIOCSLCKTRMIOS:
1025 if (!capable(CAP_SYS_ADMIN))
1026 return -EPERM;
1027 copy_termios_locked(real_tty, &kterm);
1028 if (user_termios_to_kernel_termios(&kterm,
1029 (struct termios __user *) arg))
1030 return -EFAULT;
1031 mutex_lock(&real_tty->termios_mutex);
1032 memcpy(real_tty->termios_locked, &kterm, sizeof(struct ktermios));
1033 mutex_unlock(&real_tty->termios_mutex);
1034 return 0;
1035#else
1036 case TIOCGLCKTRMIOS:
1037 copy_termios_locked(real_tty, &kterm);
1038 if (kernel_termios_to_user_termios_1((struct termios __user *)arg, &kterm))
1039 ret = -EFAULT;
1040 return ret;
1041 case TIOCSLCKTRMIOS:
1042 if (!capable(CAP_SYS_ADMIN))
1043 return -EPERM;
1044 copy_termios_locked(real_tty, &kterm);
1045 if (user_termios_to_kernel_termios_1(&kterm,
1046 (struct termios __user *) arg))
1047 return -EFAULT;
1048 mutex_lock(&real_tty->termios_mutex);
1049 memcpy(real_tty->termios_locked, &kterm, sizeof(struct ktermios));
1050 mutex_unlock(&real_tty->termios_mutex);
1051 return ret;
1052#endif
1053#ifdef TCGETX
1054 case TCGETX: {
1055 struct termiox ktermx;
1056 if (real_tty->termiox == NULL)
1057 return -EINVAL;
1058 mutex_lock(&real_tty->termios_mutex);
1059 memcpy(&ktermx, real_tty->termiox, sizeof(struct termiox));
1060 mutex_unlock(&real_tty->termios_mutex);
1061 if (copy_to_user(p, &ktermx, sizeof(struct termiox)))
1062 ret = -EFAULT;
1063 return ret;
1064 }
1065 case TCSETX:
1066 return set_termiox(real_tty, p, 0);
1067 case TCSETXW:
1068 return set_termiox(real_tty, p, TERMIOS_WAIT);
1069 case TCSETXF:
1070 return set_termiox(real_tty, p, TERMIOS_FLUSH);
1071#endif
1072 case TIOCGSOFTCAR:
1073 copy_termios(real_tty, &kterm);
1074 ret = put_user((kterm.c_cflag & CLOCAL) ? 1 : 0,
1075 (int __user *)arg);
1076 return ret;
1077 case TIOCSSOFTCAR:
1078 if (get_user(arg, (unsigned int __user *) arg))
1079 return -EFAULT;
1080 return tty_change_softcar(real_tty, arg);
1081 default:
1082 return -ENOIOCTLCMD;
1083 }
1084}
1085EXPORT_SYMBOL_GPL(tty_mode_ioctl);
1086
1087int tty_perform_flush(struct tty_struct *tty, unsigned long arg)
1088{
1089 struct tty_ldisc *ld;
1090 int retval = tty_check_change(tty);
1091 if (retval)
1092 return retval;
1093
1094 ld = tty_ldisc_ref_wait(tty);
1095 switch (arg) {
1096 case TCIFLUSH:
1097 if (ld && ld->ops->flush_buffer)
1098 ld->ops->flush_buffer(tty);
1099 break;
1100 case TCIOFLUSH:
1101 if (ld && ld->ops->flush_buffer)
1102 ld->ops->flush_buffer(tty);
1103 /* fall through */
1104 case TCOFLUSH:
1105 tty_driver_flush_buffer(tty);
1106 break;
1107 default:
1108 tty_ldisc_deref(ld);
1109 return -EINVAL;
1110 }
1111 tty_ldisc_deref(ld);
1112 return 0;
1113}
1114EXPORT_SYMBOL_GPL(tty_perform_flush);
1115
1116int n_tty_ioctl_helper(struct tty_struct *tty, struct file *file,
1117 unsigned int cmd, unsigned long arg)
1118{
1119 unsigned long flags;
1120 int retval;
1121
1122 switch (cmd) {
1123 case TCXONC:
1124 retval = tty_check_change(tty);
1125 if (retval)
1126 return retval;
1127 switch (arg) {
1128 case TCOOFF:
1129 if (!tty->flow_stopped) {
1130 tty->flow_stopped = 1;
1131 stop_tty(tty);
1132 }
1133 break;
1134 case TCOON:
1135 if (tty->flow_stopped) {
1136 tty->flow_stopped = 0;
1137 start_tty(tty);
1138 }
1139 break;
1140 case TCIOFF:
1141 if (STOP_CHAR(tty) != __DISABLED_CHAR)
1142 return send_prio_char(tty, STOP_CHAR(tty));
1143 break;
1144 case TCION:
1145 if (START_CHAR(tty) != __DISABLED_CHAR)
1146 return send_prio_char(tty, START_CHAR(tty));
1147 break;
1148 default:
1149 return -EINVAL;
1150 }
1151 return 0;
1152 case TCFLSH:
1153 return tty_perform_flush(tty, arg);
1154 case TIOCPKT:
1155 {
1156 int pktmode;
1157
1158 if (tty->driver->type != TTY_DRIVER_TYPE_PTY ||
1159 tty->driver->subtype != PTY_TYPE_MASTER)
1160 return -ENOTTY;
1161 if (get_user(pktmode, (int __user *) arg))
1162 return -EFAULT;
1163 spin_lock_irqsave(&tty->ctrl_lock, flags);
1164 if (pktmode) {
1165 if (!tty->packet) {
1166 tty->packet = 1;
1167 tty->link->ctrl_status = 0;
1168 }
1169 } else
1170 tty->packet = 0;
1171 spin_unlock_irqrestore(&tty->ctrl_lock, flags);
1172 return 0;
1173 }
1174 default:
1175 /* Try the mode commands */
1176 return tty_mode_ioctl(tty, file, cmd, arg);
1177 }
1178}
1179EXPORT_SYMBOL(n_tty_ioctl_helper);
generated by cgit v1.2.2 (git 2.25.0) at 2024-12-29 15:11:28 -0500