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-rw-r--r--drivers/char/tty_ioctl.c551
1 files changed, 551 insertions, 0 deletions
diff --git a/drivers/char/tty_ioctl.c b/drivers/char/tty_ioctl.c
new file mode 100644
index 000000000000..58597993954f
--- /dev/null
+++ b/drivers/char/tty_ioctl.c
@@ -0,0 +1,551 @@
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
24#include <asm/io.h>
25#include <asm/uaccess.h>
26#include <asm/system.h>
27
28#undef TTY_DEBUG_WAIT_UNTIL_SENT
29
30#undef DEBUG
31
32/*
33 * Internal flag options for termios setting behavior
34 */
35#define TERMIOS_FLUSH 1
36#define TERMIOS_WAIT 2
37#define TERMIOS_TERMIO 4
38
39void tty_wait_until_sent(struct tty_struct * tty, long timeout)
40{
41 DECLARE_WAITQUEUE(wait, current);
42
43#ifdef TTY_DEBUG_WAIT_UNTIL_SENT
44 char buf[64];
45
46 printk(KERN_DEBUG "%s wait until sent...\n", tty_name(tty, buf));
47#endif
48 if (!tty->driver->chars_in_buffer)
49 return;
50 add_wait_queue(&tty->write_wait, &wait);
51 if (!timeout)
52 timeout = MAX_SCHEDULE_TIMEOUT;
53 do {
54#ifdef TTY_DEBUG_WAIT_UNTIL_SENT
55 printk(KERN_DEBUG "waiting %s...(%d)\n", tty_name(tty, buf),
56 tty->driver->chars_in_buffer(tty));
57#endif
58 set_current_state(TASK_INTERRUPTIBLE);
59 if (signal_pending(current))
60 goto stop_waiting;
61 if (!tty->driver->chars_in_buffer(tty))
62 break;
63 timeout = schedule_timeout(timeout);
64 } while (timeout);
65 if (tty->driver->wait_until_sent)
66 tty->driver->wait_until_sent(tty, timeout);
67stop_waiting:
68 set_current_state(TASK_RUNNING);
69 remove_wait_queue(&tty->write_wait, &wait);
70}
71
72EXPORT_SYMBOL(tty_wait_until_sent);
73
74static void unset_locked_termios(struct termios *termios,
75 struct termios *old,
76 struct termios *locked)
77{
78 int i;
79
80#define NOSET_MASK(x,y,z) (x = ((x) & ~(z)) | ((y) & (z)))
81
82 if (!locked) {
83 printk(KERN_WARNING "Warning?!? termios_locked is NULL.\n");
84 return;
85 }
86
87 NOSET_MASK(termios->c_iflag, old->c_iflag, locked->c_iflag);
88 NOSET_MASK(termios->c_oflag, old->c_oflag, locked->c_oflag);
89 NOSET_MASK(termios->c_cflag, old->c_cflag, locked->c_cflag);
90 NOSET_MASK(termios->c_lflag, old->c_lflag, locked->c_lflag);
91 termios->c_line = locked->c_line ? old->c_line : termios->c_line;
92 for (i=0; i < NCCS; i++)
93 termios->c_cc[i] = locked->c_cc[i] ?
94 old->c_cc[i] : termios->c_cc[i];
95}
96
97static void change_termios(struct tty_struct * tty, struct termios * new_termios)
98{
99 int canon_change;
100 struct termios old_termios = *tty->termios;
101 struct tty_ldisc *ld;
102
103 /*
104 * Perform the actual termios internal changes under lock.
105 */
106
107
108 /* FIXME: we need to decide on some locking/ordering semantics
109 for the set_termios notification eventually */
110 down(&tty->termios_sem);
111
112 *tty->termios = *new_termios;
113 unset_locked_termios(tty->termios, &old_termios, tty->termios_locked);
114 canon_change = (old_termios.c_lflag ^ tty->termios->c_lflag) & ICANON;
115 if (canon_change) {
116 memset(&tty->read_flags, 0, sizeof tty->read_flags);
117 tty->canon_head = tty->read_tail;
118 tty->canon_data = 0;
119 tty->erasing = 0;
120 }
121
122
123 if (canon_change && !L_ICANON(tty) && tty->read_cnt)
124 /* Get characters left over from canonical mode. */
125 wake_up_interruptible(&tty->read_wait);
126
127 /* See if packet mode change of state. */
128
129 if (tty->link && tty->link->packet) {
130 int old_flow = ((old_termios.c_iflag & IXON) &&
131 (old_termios.c_cc[VSTOP] == '\023') &&
132 (old_termios.c_cc[VSTART] == '\021'));
133 int new_flow = (I_IXON(tty) &&
134 STOP_CHAR(tty) == '\023' &&
135 START_CHAR(tty) == '\021');
136 if (old_flow != new_flow) {
137 tty->ctrl_status &= ~(TIOCPKT_DOSTOP | TIOCPKT_NOSTOP);
138 if (new_flow)
139 tty->ctrl_status |= TIOCPKT_DOSTOP;
140 else
141 tty->ctrl_status |= TIOCPKT_NOSTOP;
142 wake_up_interruptible(&tty->link->read_wait);
143 }
144 }
145
146 if (tty->driver->set_termios)
147 (*tty->driver->set_termios)(tty, &old_termios);
148
149 ld = tty_ldisc_ref(tty);
150 if (ld != NULL) {
151 if (ld->set_termios)
152 (ld->set_termios)(tty, &old_termios);
153 tty_ldisc_deref(ld);
154 }
155 up(&tty->termios_sem);
156}
157
158static int set_termios(struct tty_struct * tty, void __user *arg, int opt)
159{
160 struct termios tmp_termios;
161 struct tty_ldisc *ld;
162 int retval = tty_check_change(tty);
163
164 if (retval)
165 return retval;
166
167 if (opt & TERMIOS_TERMIO) {
168 memcpy(&tmp_termios, tty->termios, sizeof(struct termios));
169 if (user_termio_to_kernel_termios(&tmp_termios,
170 (struct termio __user *)arg))
171 return -EFAULT;
172 } else {
173 if (user_termios_to_kernel_termios(&tmp_termios,
174 (struct termios __user *)arg))
175 return -EFAULT;
176 }
177
178 ld = tty_ldisc_ref(tty);
179
180 if (ld != NULL) {
181 if ((opt & TERMIOS_FLUSH) && ld->flush_buffer)
182 ld->flush_buffer(tty);
183 tty_ldisc_deref(ld);
184 }
185
186 if (opt & TERMIOS_WAIT) {
187 tty_wait_until_sent(tty, 0);
188 if (signal_pending(current))
189 return -EINTR;
190 }
191
192 change_termios(tty, &tmp_termios);
193 return 0;
194}
195
196static int get_termio(struct tty_struct * tty, struct termio __user * termio)
197{
198 if (kernel_termios_to_user_termio(termio, tty->termios))
199 return -EFAULT;
200 return 0;
201}
202
203static unsigned long inq_canon(struct tty_struct * tty)
204{
205 int nr, head, tail;
206
207 if (!tty->canon_data || !tty->read_buf)
208 return 0;
209 head = tty->canon_head;
210 tail = tty->read_tail;
211 nr = (head - tail) & (N_TTY_BUF_SIZE-1);
212 /* Skip EOF-chars.. */
213 while (head != tail) {
214 if (test_bit(tail, tty->read_flags) &&
215 tty->read_buf[tail] == __DISABLED_CHAR)
216 nr--;
217 tail = (tail+1) & (N_TTY_BUF_SIZE-1);
218 }
219 return nr;
220}
221
222#ifdef TIOCGETP
223/*
224 * These are deprecated, but there is limited support..
225 *
226 * The "sg_flags" translation is a joke..
227 */
228static int get_sgflags(struct tty_struct * tty)
229{
230 int flags = 0;
231
232 if (!(tty->termios->c_lflag & ICANON)) {
233 if (tty->termios->c_lflag & ISIG)
234 flags |= 0x02; /* cbreak */
235 else
236 flags |= 0x20; /* raw */
237 }
238 if (tty->termios->c_lflag & ECHO)
239 flags |= 0x08; /* echo */
240 if (tty->termios->c_oflag & OPOST)
241 if (tty->termios->c_oflag & ONLCR)
242 flags |= 0x10; /* crmod */
243 return flags;
244}
245
246static int get_sgttyb(struct tty_struct * tty, struct sgttyb __user * sgttyb)
247{
248 struct sgttyb tmp;
249
250 down(&tty->termios_sem);
251 tmp.sg_ispeed = 0;
252 tmp.sg_ospeed = 0;
253 tmp.sg_erase = tty->termios->c_cc[VERASE];
254 tmp.sg_kill = tty->termios->c_cc[VKILL];
255 tmp.sg_flags = get_sgflags(tty);
256 up(&tty->termios_sem);
257
258 return copy_to_user(sgttyb, &tmp, sizeof(tmp)) ? -EFAULT : 0;
259}
260
261static void set_sgflags(struct termios * termios, int flags)
262{
263 termios->c_iflag = ICRNL | IXON;
264 termios->c_oflag = 0;
265 termios->c_lflag = ISIG | ICANON;
266 if (flags & 0x02) { /* cbreak */
267 termios->c_iflag = 0;
268 termios->c_lflag &= ~ICANON;
269 }
270 if (flags & 0x08) { /* echo */
271 termios->c_lflag |= ECHO | ECHOE | ECHOK |
272 ECHOCTL | ECHOKE | IEXTEN;
273 }
274 if (flags & 0x10) { /* crmod */
275 termios->c_oflag |= OPOST | ONLCR;
276 }
277 if (flags & 0x20) { /* raw */
278 termios->c_iflag = 0;
279 termios->c_lflag &= ~(ISIG | ICANON);
280 }
281 if (!(termios->c_lflag & ICANON)) {
282 termios->c_cc[VMIN] = 1;
283 termios->c_cc[VTIME] = 0;
284 }
285}
286
287static int set_sgttyb(struct tty_struct * tty, struct sgttyb __user * sgttyb)
288{
289 int retval;
290 struct sgttyb tmp;
291 struct termios termios;
292
293 retval = tty_check_change(tty);
294 if (retval)
295 return retval;
296
297 if (copy_from_user(&tmp, sgttyb, sizeof(tmp)))
298 return -EFAULT;
299
300 down(&tty->termios_sem);
301 termios = *tty->termios;
302 termios.c_cc[VERASE] = tmp.sg_erase;
303 termios.c_cc[VKILL] = tmp.sg_kill;
304 set_sgflags(&termios, tmp.sg_flags);
305 up(&tty->termios_sem);
306 change_termios(tty, &termios);
307 return 0;
308}
309#endif
310
311#ifdef TIOCGETC
312static int get_tchars(struct tty_struct * tty, struct tchars __user * tchars)
313{
314 struct tchars tmp;
315
316 tmp.t_intrc = tty->termios->c_cc[VINTR];
317 tmp.t_quitc = tty->termios->c_cc[VQUIT];
318 tmp.t_startc = tty->termios->c_cc[VSTART];
319 tmp.t_stopc = tty->termios->c_cc[VSTOP];
320 tmp.t_eofc = tty->termios->c_cc[VEOF];
321 tmp.t_brkc = tty->termios->c_cc[VEOL2]; /* what is brkc anyway? */
322 return copy_to_user(tchars, &tmp, sizeof(tmp)) ? -EFAULT : 0;
323}
324
325static int set_tchars(struct tty_struct * tty, struct tchars __user * tchars)
326{
327 struct tchars tmp;
328
329 if (copy_from_user(&tmp, tchars, sizeof(tmp)))
330 return -EFAULT;
331 tty->termios->c_cc[VINTR] = tmp.t_intrc;
332 tty->termios->c_cc[VQUIT] = tmp.t_quitc;
333 tty->termios->c_cc[VSTART] = tmp.t_startc;
334 tty->termios->c_cc[VSTOP] = tmp.t_stopc;
335 tty->termios->c_cc[VEOF] = tmp.t_eofc;
336 tty->termios->c_cc[VEOL2] = tmp.t_brkc; /* what is brkc anyway? */
337 return 0;
338}
339#endif
340
341#ifdef TIOCGLTC
342static int get_ltchars(struct tty_struct * tty, struct ltchars __user * ltchars)
343{
344 struct ltchars tmp;
345
346 tmp.t_suspc = tty->termios->c_cc[VSUSP];
347 tmp.t_dsuspc = tty->termios->c_cc[VSUSP]; /* what is dsuspc anyway? */
348 tmp.t_rprntc = tty->termios->c_cc[VREPRINT];
349 tmp.t_flushc = tty->termios->c_cc[VEOL2]; /* what is flushc anyway? */
350 tmp.t_werasc = tty->termios->c_cc[VWERASE];
351 tmp.t_lnextc = tty->termios->c_cc[VLNEXT];
352 return copy_to_user(ltchars, &tmp, sizeof(tmp)) ? -EFAULT : 0;
353}
354
355static int set_ltchars(struct tty_struct * tty, struct ltchars __user * ltchars)
356{
357 struct ltchars tmp;
358
359 if (copy_from_user(&tmp, ltchars, sizeof(tmp)))
360 return -EFAULT;
361
362 tty->termios->c_cc[VSUSP] = tmp.t_suspc;
363 tty->termios->c_cc[VEOL2] = tmp.t_dsuspc; /* what is dsuspc anyway? */
364 tty->termios->c_cc[VREPRINT] = tmp.t_rprntc;
365 tty->termios->c_cc[VEOL2] = tmp.t_flushc; /* what is flushc anyway? */
366 tty->termios->c_cc[VWERASE] = tmp.t_werasc;
367 tty->termios->c_cc[VLNEXT] = tmp.t_lnextc;
368 return 0;
369}
370#endif
371
372/*
373 * Send a high priority character to the tty.
374 */
375static void send_prio_char(struct tty_struct *tty, char ch)
376{
377 int was_stopped = tty->stopped;
378
379 if (tty->driver->send_xchar) {
380 tty->driver->send_xchar(tty, ch);
381 return;
382 }
383 if (was_stopped)
384 start_tty(tty);
385 tty->driver->write(tty, &ch, 1);
386 if (was_stopped)
387 stop_tty(tty);
388}
389
390int n_tty_ioctl(struct tty_struct * tty, struct file * file,
391 unsigned int cmd, unsigned long arg)
392{
393 struct tty_struct * real_tty;
394 void __user *p = (void __user *)arg;
395 int retval;
396 struct tty_ldisc *ld;
397
398 if (tty->driver->type == TTY_DRIVER_TYPE_PTY &&
399 tty->driver->subtype == PTY_TYPE_MASTER)
400 real_tty = tty->link;
401 else
402 real_tty = tty;
403
404 switch (cmd) {
405#ifdef TIOCGETP
406 case TIOCGETP:
407 return get_sgttyb(real_tty, (struct sgttyb __user *) arg);
408 case TIOCSETP:
409 case TIOCSETN:
410 return set_sgttyb(real_tty, (struct sgttyb __user *) arg);
411#endif
412#ifdef TIOCGETC
413 case TIOCGETC:
414 return get_tchars(real_tty, p);
415 case TIOCSETC:
416 return set_tchars(real_tty, p);
417#endif
418#ifdef TIOCGLTC
419 case TIOCGLTC:
420 return get_ltchars(real_tty, p);
421 case TIOCSLTC:
422 return set_ltchars(real_tty, p);
423#endif
424 case TCGETS:
425 if (kernel_termios_to_user_termios((struct termios __user *)arg, real_tty->termios))
426 return -EFAULT;
427 return 0;
428 case TCSETSF:
429 return set_termios(real_tty, p, TERMIOS_FLUSH | TERMIOS_WAIT);
430 case TCSETSW:
431 return set_termios(real_tty, p, TERMIOS_WAIT);
432 case TCSETS:
433 return set_termios(real_tty, p, 0);
434 case TCGETA:
435 return get_termio(real_tty, p);
436 case TCSETAF:
437 return set_termios(real_tty, p, TERMIOS_FLUSH | TERMIOS_WAIT | TERMIOS_TERMIO);
438 case TCSETAW:
439 return set_termios(real_tty, p, TERMIOS_WAIT | TERMIOS_TERMIO);
440 case TCSETA:
441 return set_termios(real_tty, p, TERMIOS_TERMIO);
442 case TCXONC:
443 retval = tty_check_change(tty);
444 if (retval)
445 return retval;
446 switch (arg) {
447 case TCOOFF:
448 if (!tty->flow_stopped) {
449 tty->flow_stopped = 1;
450 stop_tty(tty);
451 }
452 break;
453 case TCOON:
454 if (tty->flow_stopped) {
455 tty->flow_stopped = 0;
456 start_tty(tty);
457 }
458 break;
459 case TCIOFF:
460 if (STOP_CHAR(tty) != __DISABLED_CHAR)
461 send_prio_char(tty, STOP_CHAR(tty));
462 break;
463 case TCION:
464 if (START_CHAR(tty) != __DISABLED_CHAR)
465 send_prio_char(tty, START_CHAR(tty));
466 break;
467 default:
468 return -EINVAL;
469 }
470 return 0;
471 case TCFLSH:
472 retval = tty_check_change(tty);
473 if (retval)
474 return retval;
475
476 ld = tty_ldisc_ref(tty);
477 switch (arg) {
478 case TCIFLUSH:
479 if (ld->flush_buffer)
480 ld->flush_buffer(tty);
481 break;
482 case TCIOFLUSH:
483 if (ld->flush_buffer)
484 ld->flush_buffer(tty);
485 /* fall through */
486 case TCOFLUSH:
487 if (tty->driver->flush_buffer)
488 tty->driver->flush_buffer(tty);
489 break;
490 default:
491 tty_ldisc_deref(ld);
492 return -EINVAL;
493 }
494 tty_ldisc_deref(ld);
495 return 0;
496 case TIOCOUTQ:
497 return put_user(tty->driver->chars_in_buffer ?
498 tty->driver->chars_in_buffer(tty) : 0,
499 (int __user *) arg);
500 case TIOCINQ:
501 retval = tty->read_cnt;
502 if (L_ICANON(tty))
503 retval = inq_canon(tty);
504 return put_user(retval, (unsigned int __user *) arg);
505 case TIOCGLCKTRMIOS:
506 if (kernel_termios_to_user_termios((struct termios __user *)arg, real_tty->termios_locked))
507 return -EFAULT;
508 return 0;
509
510 case TIOCSLCKTRMIOS:
511 if (!capable(CAP_SYS_ADMIN))
512 return -EPERM;
513 if (user_termios_to_kernel_termios(real_tty->termios_locked, (struct termios __user *) arg))
514 return -EFAULT;
515 return 0;
516
517 case TIOCPKT:
518 {
519 int pktmode;
520
521 if (tty->driver->type != TTY_DRIVER_TYPE_PTY ||
522 tty->driver->subtype != PTY_TYPE_MASTER)
523 return -ENOTTY;
524 if (get_user(pktmode, (int __user *) arg))
525 return -EFAULT;
526 if (pktmode) {
527 if (!tty->packet) {
528 tty->packet = 1;
529 tty->link->ctrl_status = 0;
530 }
531 } else
532 tty->packet = 0;
533 return 0;
534 }
535 case TIOCGSOFTCAR:
536 return put_user(C_CLOCAL(tty) ? 1 : 0, (int __user *)arg);
537 case TIOCSSOFTCAR:
538 if (get_user(arg, (unsigned int __user *) arg))
539 return -EFAULT;
540 down(&tty->termios_sem);
541 tty->termios->c_cflag =
542 ((tty->termios->c_cflag & ~CLOCAL) |
543 (arg ? CLOCAL : 0));
544 up(&tty->termios_sem);
545 return 0;
546 default:
547 return -ENOIOCTLCMD;
548 }
549}
550
551EXPORT_SYMBOL(n_tty_ioctl);
generated by cgit v1.2.2 (git 2.25.0) at 2024-12-14 03:37:50 -0500