2 * Copyright (C) 1991, 1992, 1993, 1994 Linus Torvalds
4 * Modified by Fred N. van Kempen, 01/29/93, to add line disciplines
5 * which can be dynamically activated and de-activated by the line
6 * discipline handling modules (like SLIP).
9 #include <linux/types.h>
10 #include <linux/termios.h>
11 #include <linux/errno.h>
12 #include <linux/sched.h>
13 #include <linux/kernel.h>
14 #include <linux/major.h>
15 #include <linux/tty.h>
16 #include <linux/fcntl.h>
17 #include <linux/string.h>
19 #include <linux/module.h>
20 #include <linux/bitops.h>
21 #include <linux/mutex.h>
22 #include <linux/compat.h>
25 #include <asm/uaccess.h>
27 #undef TTY_DEBUG_WAIT_UNTIL_SENT
32 * Internal flag options for termios setting behavior
34 #define TERMIOS_FLUSH 1
35 #define TERMIOS_WAIT 2
36 #define TERMIOS_TERMIO 4
41 * tty_chars_in_buffer - characters pending
44 * Return the number of bytes of data in the device private
45 * output queue. If no private method is supplied there is assumed
46 * to be no queue on the device.
49 int tty_chars_in_buffer(struct tty_struct *tty)
51 if (tty->ops->chars_in_buffer)
52 return tty->ops->chars_in_buffer(tty);
56 EXPORT_SYMBOL(tty_chars_in_buffer);
59 * tty_write_room - write queue space
62 * Return the number of bytes that can be queued to this device
63 * at the present time. The result should be treated as a guarantee
64 * and the driver cannot offer a value it later shrinks by more than
65 * the number of bytes written. If no method is provided 2K is always
66 * returned and data may be lost as there will be no flow control.
69 int tty_write_room(struct tty_struct *tty)
71 if (tty->ops->write_room)
72 return tty->ops->write_room(tty);
75 EXPORT_SYMBOL(tty_write_room);
78 * tty_driver_flush_buffer - discard internal buffer
81 * Discard the internal output buffer for this device. If no method
82 * is provided then either the buffer cannot be hardware flushed or
83 * there is no buffer driver side.
85 void tty_driver_flush_buffer(struct tty_struct *tty)
87 if (tty->ops->flush_buffer)
88 tty->ops->flush_buffer(tty);
90 EXPORT_SYMBOL(tty_driver_flush_buffer);
93 * tty_throttle - flow control
96 * Indicate that a tty should stop transmitting data down the stack.
97 * Takes the termios rwsem to protect against parallel throttle/unthrottle
98 * and also to ensure the driver can consistently reference its own
99 * termios data at this point when implementing software flow control.
102 void tty_throttle(struct tty_struct *tty)
104 down_write(&tty->termios_rwsem);
105 /* check TTY_THROTTLED first so it indicates our state */
106 if (!test_and_set_bit(TTY_THROTTLED, &tty->flags) &&
108 tty->ops->throttle(tty);
109 tty->flow_change = 0;
110 up_write(&tty->termios_rwsem);
112 EXPORT_SYMBOL(tty_throttle);
115 * tty_unthrottle - flow control
118 * Indicate that a tty may continue transmitting data down the stack.
119 * Takes the termios rwsem to protect against parallel throttle/unthrottle
120 * and also to ensure the driver can consistently reference its own
121 * termios data at this point when implementing software flow control.
123 * Drivers should however remember that the stack can issue a throttle,
124 * then change flow control method, then unthrottle.
127 void tty_unthrottle(struct tty_struct *tty)
129 down_write(&tty->termios_rwsem);
130 if (test_and_clear_bit(TTY_THROTTLED, &tty->flags) &&
131 tty->ops->unthrottle)
132 tty->ops->unthrottle(tty);
133 tty->flow_change = 0;
134 up_write(&tty->termios_rwsem);
136 EXPORT_SYMBOL(tty_unthrottle);
139 * tty_throttle_safe - flow control
142 * Similar to tty_throttle() but will only attempt throttle
143 * if tty->flow_change is TTY_THROTTLE_SAFE. Prevents an accidental
144 * throttle due to race conditions when throttling is conditional
145 * on factors evaluated prior to throttling.
147 * Returns 0 if tty is throttled (or was already throttled)
150 int tty_throttle_safe(struct tty_struct *tty)
154 mutex_lock(&tty->throttle_mutex);
155 if (!test_bit(TTY_THROTTLED, &tty->flags)) {
156 if (tty->flow_change != TTY_THROTTLE_SAFE)
159 set_bit(TTY_THROTTLED, &tty->flags);
160 if (tty->ops->throttle)
161 tty->ops->throttle(tty);
164 mutex_unlock(&tty->throttle_mutex);
170 * tty_unthrottle_safe - flow control
173 * Similar to tty_unthrottle() but will only attempt unthrottle
174 * if tty->flow_change is TTY_UNTHROTTLE_SAFE. Prevents an accidental
175 * unthrottle due to race conditions when unthrottling is conditional
176 * on factors evaluated prior to unthrottling.
178 * Returns 0 if tty is unthrottled (or was already unthrottled)
181 int tty_unthrottle_safe(struct tty_struct *tty)
185 mutex_lock(&tty->throttle_mutex);
186 if (test_bit(TTY_THROTTLED, &tty->flags)) {
187 if (tty->flow_change != TTY_UNTHROTTLE_SAFE)
190 clear_bit(TTY_THROTTLED, &tty->flags);
191 if (tty->ops->unthrottle)
192 tty->ops->unthrottle(tty);
195 mutex_unlock(&tty->throttle_mutex);
201 * tty_wait_until_sent - wait for I/O to finish
202 * @tty: tty we are waiting for
203 * @timeout: how long we will wait
205 * Wait for characters pending in a tty driver to hit the wire, or
206 * for a timeout to occur (eg due to flow control)
211 void tty_wait_until_sent(struct tty_struct *tty, long timeout)
213 #ifdef TTY_DEBUG_WAIT_UNTIL_SENT
216 printk(KERN_DEBUG "%s wait until sent...\n", tty_name(tty, buf));
219 timeout = MAX_SCHEDULE_TIMEOUT;
220 if (wait_event_interruptible_timeout(tty->write_wait,
221 !tty_chars_in_buffer(tty), timeout) >= 0) {
222 if (tty->ops->wait_until_sent)
223 tty->ops->wait_until_sent(tty, timeout);
226 EXPORT_SYMBOL(tty_wait_until_sent);
230 * Termios Helper Methods
233 static void unset_locked_termios(struct ktermios *termios,
234 struct ktermios *old,
235 struct ktermios *locked)
239 #define NOSET_MASK(x, y, z) (x = ((x) & ~(z)) | ((y) & (z)))
242 printk(KERN_WARNING "Warning?!? termios_locked is NULL.\n");
246 NOSET_MASK(termios->c_iflag, old->c_iflag, locked->c_iflag);
247 NOSET_MASK(termios->c_oflag, old->c_oflag, locked->c_oflag);
248 NOSET_MASK(termios->c_cflag, old->c_cflag, locked->c_cflag);
249 NOSET_MASK(termios->c_lflag, old->c_lflag, locked->c_lflag);
250 termios->c_line = locked->c_line ? old->c_line : termios->c_line;
251 for (i = 0; i < NCCS; i++)
252 termios->c_cc[i] = locked->c_cc[i] ?
253 old->c_cc[i] : termios->c_cc[i];
254 /* FIXME: What should we do for i/ospeed */
258 * Routine which returns the baud rate of the tty
260 * Note that the baud_table needs to be kept in sync with the
261 * include/asm/termbits.h file.
263 static const speed_t baud_table[] = {
264 0, 50, 75, 110, 134, 150, 200, 300, 600, 1200, 1800, 2400, 4800,
265 9600, 19200, 38400, 57600, 115200, 230400, 460800,
267 76800, 153600, 307200, 614400, 921600
269 500000, 576000, 921600, 1000000, 1152000, 1500000, 2000000,
270 2500000, 3000000, 3500000, 4000000
275 static const tcflag_t baud_bits[] = {
276 B0, B50, B75, B110, B134, B150, B200, B300, B600,
277 B1200, B1800, B2400, B4800, B9600, B19200, B38400,
278 B57600, B115200, B230400, B460800, B500000, B576000,
279 B921600, B1000000, B1152000, B1500000, B2000000, B2500000,
280 B3000000, B3500000, B4000000
283 static const tcflag_t baud_bits[] = {
284 B0, B50, B75, B110, B134, B150, B200, B300, B600,
285 B1200, B1800, B2400, B4800, B9600, B19200, B38400,
286 B57600, B115200, B230400, B460800, B76800, B153600,
287 B307200, B614400, B921600
291 static int n_baud_table = ARRAY_SIZE(baud_table);
294 * tty_termios_baud_rate
295 * @termios: termios structure
297 * Convert termios baud rate data into a speed. This should be called
298 * with the termios lock held if this termios is a terminal termios
299 * structure. May change the termios data. Device drivers can call this
300 * function but should use ->c_[io]speed directly as they are updated.
305 speed_t tty_termios_baud_rate(struct ktermios *termios)
309 cbaud = termios->c_cflag & CBAUD;
312 /* Magic token for arbitrary speed via c_ispeed/c_ospeed */
314 return termios->c_ospeed;
316 if (cbaud & CBAUDEX) {
319 if (cbaud < 1 || cbaud + 15 > n_baud_table)
320 termios->c_cflag &= ~CBAUDEX;
324 return baud_table[cbaud];
326 EXPORT_SYMBOL(tty_termios_baud_rate);
329 * tty_termios_input_baud_rate
330 * @termios: termios structure
332 * Convert termios baud rate data into a speed. This should be called
333 * with the termios lock held if this termios is a terminal termios
334 * structure. May change the termios data. Device drivers can call this
335 * function but should use ->c_[io]speed directly as they are updated.
340 speed_t tty_termios_input_baud_rate(struct ktermios *termios)
343 unsigned int cbaud = (termios->c_cflag >> IBSHIFT) & CBAUD;
346 return tty_termios_baud_rate(termios);
348 /* Magic token for arbitrary speed via c_ispeed*/
350 return termios->c_ispeed;
352 if (cbaud & CBAUDEX) {
355 if (cbaud < 1 || cbaud + 15 > n_baud_table)
356 termios->c_cflag &= ~(CBAUDEX << IBSHIFT);
360 return baud_table[cbaud];
362 return tty_termios_baud_rate(termios);
365 EXPORT_SYMBOL(tty_termios_input_baud_rate);
368 * tty_termios_encode_baud_rate
369 * @termios: ktermios structure holding user requested state
370 * @ispeed: input speed
371 * @ospeed: output speed
373 * Encode the speeds set into the passed termios structure. This is
374 * used as a library helper for drivers so that they can report back
375 * the actual speed selected when it differs from the speed requested
377 * For maximal back compatibility with legacy SYS5/POSIX *nix behaviour
378 * we need to carefully set the bits when the user does not get the
379 * desired speed. We allow small margins and preserve as much of possible
380 * of the input intent to keep compatibility.
382 * Locking: Caller should hold termios lock. This is already held
383 * when calling this function from the driver termios handler.
385 * The ifdefs deal with platforms whose owners have yet to update them
386 * and will all go away once this is done.
389 void tty_termios_encode_baud_rate(struct ktermios *termios,
390 speed_t ibaud, speed_t obaud)
393 int ifound = -1, ofound = -1;
394 int iclose = ibaud/50, oclose = obaud/50;
397 if (obaud == 0) /* CD dropped */
398 ibaud = 0; /* Clear ibaud to be sure */
400 termios->c_ispeed = ibaud;
401 termios->c_ospeed = obaud;
404 /* If the user asked for a precise weird speed give a precise weird
405 answer. If they asked for a Bfoo speed they may have problems
406 digesting non-exact replies so fuzz a bit */
408 if ((termios->c_cflag & CBAUD) == BOTHER)
410 if (((termios->c_cflag >> IBSHIFT) & CBAUD) == BOTHER)
412 if ((termios->c_cflag >> IBSHIFT) & CBAUD)
413 ibinput = 1; /* An input speed was specified */
415 termios->c_cflag &= ~CBAUD;
418 * Our goal is to find a close match to the standard baud rate
419 * returned. Walk the baud rate table and if we get a very close
420 * match then report back the speed as a POSIX Bxxxx value by
425 if (obaud - oclose <= baud_table[i] &&
426 obaud + oclose >= baud_table[i]) {
427 termios->c_cflag |= baud_bits[i];
430 if (ibaud - iclose <= baud_table[i] &&
431 ibaud + iclose >= baud_table[i]) {
432 /* For the case input == output don't set IBAUD bits
433 if the user didn't do so */
434 if (ofound == i && !ibinput)
439 termios->c_cflag |= (baud_bits[i] << IBSHIFT);
443 } while (++i < n_baud_table);
446 * If we found no match then use BOTHER if provided or warn
447 * the user their platform maintainer needs to wake up if not.
451 termios->c_cflag |= BOTHER;
452 /* Set exact input bits only if the input and output differ or the
454 if (ifound == -1 && (ibaud != obaud || ibinput))
455 termios->c_cflag |= (BOTHER << IBSHIFT);
457 if (ifound == -1 || ofound == -1) {
458 printk_once(KERN_WARNING "tty: Unable to return correct "
459 "speed data as your architecture needs updating.\n");
463 EXPORT_SYMBOL_GPL(tty_termios_encode_baud_rate);
466 * tty_encode_baud_rate - set baud rate of the tty
467 * @ibaud: input baud rate
468 * @obad: output baud rate
470 * Update the current termios data for the tty with the new speed
471 * settings. The caller must hold the termios_rwsem for the tty in
475 void tty_encode_baud_rate(struct tty_struct *tty, speed_t ibaud, speed_t obaud)
477 tty_termios_encode_baud_rate(&tty->termios, ibaud, obaud);
479 EXPORT_SYMBOL_GPL(tty_encode_baud_rate);
482 * tty_termios_copy_hw - copy hardware settings
486 * Propagate the hardware specific terminal setting bits from
487 * the old termios structure to the new one. This is used in cases
488 * where the hardware does not support reconfiguration or as a helper
489 * in some cases where only minimal reconfiguration is supported
492 void tty_termios_copy_hw(struct ktermios *new, struct ktermios *old)
494 /* The bits a dumb device handles in software. Smart devices need
495 to always provide a set_termios method */
496 new->c_cflag &= HUPCL | CREAD | CLOCAL;
497 new->c_cflag |= old->c_cflag & ~(HUPCL | CREAD | CLOCAL);
498 new->c_ispeed = old->c_ispeed;
499 new->c_ospeed = old->c_ospeed;
501 EXPORT_SYMBOL(tty_termios_copy_hw);
504 * tty_termios_hw_change - check for setting change
506 * @b: termios to compare
508 * Check if any of the bits that affect a dumb device have changed
509 * between the two termios structures, or a speed change is needed.
512 int tty_termios_hw_change(struct ktermios *a, struct ktermios *b)
514 if (a->c_ispeed != b->c_ispeed || a->c_ospeed != b->c_ospeed)
516 if ((a->c_cflag ^ b->c_cflag) & ~(HUPCL | CREAD | CLOCAL))
520 EXPORT_SYMBOL(tty_termios_hw_change);
523 * tty_set_termios - update termios values
524 * @tty: tty to update
525 * @new_termios: desired new value
527 * Perform updates to the termios values set on this terminal. There
528 * is a bit of layering violation here with n_tty in terms of the
529 * internal knowledge of this function.
531 * A master pty's termios should never be set.
533 * Locking: termios_rwsem
536 int tty_set_termios(struct tty_struct *tty, struct ktermios *new_termios)
538 struct ktermios old_termios;
539 struct tty_ldisc *ld;
542 WARN_ON(tty->driver->type == TTY_DRIVER_TYPE_PTY &&
543 tty->driver->subtype == PTY_TYPE_MASTER);
545 * Perform the actual termios internal changes under lock.
549 /* FIXME: we need to decide on some locking/ordering semantics
550 for the set_termios notification eventually */
551 down_write(&tty->termios_rwsem);
552 old_termios = tty->termios;
553 tty->termios = *new_termios;
554 unset_locked_termios(&tty->termios, &old_termios, &tty->termios_locked);
556 /* See if packet mode change of state. */
557 if (tty->link && tty->link->packet) {
558 int extproc = (old_termios.c_lflag & EXTPROC) |
559 (tty->termios.c_lflag & EXTPROC);
560 int old_flow = ((old_termios.c_iflag & IXON) &&
561 (old_termios.c_cc[VSTOP] == '\023') &&
562 (old_termios.c_cc[VSTART] == '\021'));
563 int new_flow = (I_IXON(tty) &&
564 STOP_CHAR(tty) == '\023' &&
565 START_CHAR(tty) == '\021');
566 if ((old_flow != new_flow) || extproc) {
567 spin_lock_irqsave(&tty->ctrl_lock, flags);
568 if (old_flow != new_flow) {
569 tty->ctrl_status &= ~(TIOCPKT_DOSTOP | TIOCPKT_NOSTOP);
571 tty->ctrl_status |= TIOCPKT_DOSTOP;
573 tty->ctrl_status |= TIOCPKT_NOSTOP;
576 tty->ctrl_status |= TIOCPKT_IOCTL;
577 spin_unlock_irqrestore(&tty->ctrl_lock, flags);
578 wake_up_interruptible(&tty->link->read_wait);
582 if (tty->ops->set_termios)
583 (*tty->ops->set_termios)(tty, &old_termios);
585 tty_termios_copy_hw(&tty->termios, &old_termios);
587 ld = tty_ldisc_ref(tty);
589 if (ld->ops->set_termios)
590 (ld->ops->set_termios)(tty, &old_termios);
593 up_write(&tty->termios_rwsem);
596 EXPORT_SYMBOL_GPL(tty_set_termios);
599 * set_termios - set termios values for a tty
600 * @tty: terminal device
602 * @opt: option information
604 * Helper function to prepare termios data and run necessary other
605 * functions before using tty_set_termios to do the actual changes.
608 * Called functions take ldisc and termios_rwsem locks
611 static int set_termios(struct tty_struct *tty, void __user *arg, int opt)
613 struct ktermios tmp_termios;
614 struct tty_ldisc *ld;
615 int retval = tty_check_change(tty);
620 down_read(&tty->termios_rwsem);
621 tmp_termios = tty->termios;
622 up_read(&tty->termios_rwsem);
624 if (opt & TERMIOS_TERMIO) {
625 if (user_termio_to_kernel_termios(&tmp_termios,
626 (struct termio __user *)arg))
629 } else if (opt & TERMIOS_OLD) {
630 if (user_termios_to_kernel_termios_1(&tmp_termios,
631 (struct termios __user *)arg))
634 if (user_termios_to_kernel_termios(&tmp_termios,
635 (struct termios2 __user *)arg))
639 } else if (user_termios_to_kernel_termios(&tmp_termios,
640 (struct termios __user *)arg))
644 /* If old style Bfoo values are used then load c_ispeed/c_ospeed
645 * with the real speed so its unconditionally usable */
646 tmp_termios.c_ispeed = tty_termios_input_baud_rate(&tmp_termios);
647 tmp_termios.c_ospeed = tty_termios_baud_rate(&tmp_termios);
649 ld = tty_ldisc_ref(tty);
652 if ((opt & TERMIOS_FLUSH) && ld->ops->flush_buffer)
653 ld->ops->flush_buffer(tty);
657 if (opt & TERMIOS_WAIT) {
658 tty_wait_until_sent(tty, 0);
659 if (signal_pending(current))
663 tty_set_termios(tty, &tmp_termios);
665 /* FIXME: Arguably if tmp_termios == tty->termios AND the
666 actual requested termios was not tmp_termios then we may
667 want to return an error as no user requested change has
672 static void copy_termios(struct tty_struct *tty, struct ktermios *kterm)
674 down_read(&tty->termios_rwsem);
675 *kterm = tty->termios;
676 up_read(&tty->termios_rwsem);
679 static void copy_termios_locked(struct tty_struct *tty, struct ktermios *kterm)
681 down_read(&tty->termios_rwsem);
682 *kterm = tty->termios_locked;
683 up_read(&tty->termios_rwsem);
686 static int get_termio(struct tty_struct *tty, struct termio __user *termio)
688 struct ktermios kterm;
689 copy_termios(tty, &kterm);
690 if (kernel_termios_to_user_termio(termio, &kterm))
699 * set_termiox - set termiox fields if possible
701 * @arg: termiox structure from user
702 * @opt: option flags for ioctl type
704 * Implement the device calling points for the SYS5 termiox ioctl
708 static int set_termiox(struct tty_struct *tty, void __user *arg, int opt)
711 struct tty_ldisc *ld;
713 if (tty->termiox == NULL)
715 if (copy_from_user(&tnew, arg, sizeof(struct termiox)))
718 ld = tty_ldisc_ref(tty);
720 if ((opt & TERMIOS_FLUSH) && ld->ops->flush_buffer)
721 ld->ops->flush_buffer(tty);
724 if (opt & TERMIOS_WAIT) {
725 tty_wait_until_sent(tty, 0);
726 if (signal_pending(current))
730 down_write(&tty->termios_rwsem);
731 if (tty->ops->set_termiox)
732 tty->ops->set_termiox(tty, &tnew);
733 up_write(&tty->termios_rwsem);
742 * These are deprecated, but there is limited support..
744 * The "sg_flags" translation is a joke..
746 static int get_sgflags(struct tty_struct *tty)
750 if (!(tty->termios.c_lflag & ICANON)) {
751 if (tty->termios.c_lflag & ISIG)
752 flags |= 0x02; /* cbreak */
754 flags |= 0x20; /* raw */
756 if (tty->termios.c_lflag & ECHO)
757 flags |= 0x08; /* echo */
758 if (tty->termios.c_oflag & OPOST)
759 if (tty->termios.c_oflag & ONLCR)
760 flags |= 0x10; /* crmod */
764 static int get_sgttyb(struct tty_struct *tty, struct sgttyb __user *sgttyb)
768 down_read(&tty->termios_rwsem);
769 tmp.sg_ispeed = tty->termios.c_ispeed;
770 tmp.sg_ospeed = tty->termios.c_ospeed;
771 tmp.sg_erase = tty->termios.c_cc[VERASE];
772 tmp.sg_kill = tty->termios.c_cc[VKILL];
773 tmp.sg_flags = get_sgflags(tty);
774 up_read(&tty->termios_rwsem);
776 return copy_to_user(sgttyb, &tmp, sizeof(tmp)) ? -EFAULT : 0;
779 static void set_sgflags(struct ktermios *termios, int flags)
781 termios->c_iflag = ICRNL | IXON;
782 termios->c_oflag = 0;
783 termios->c_lflag = ISIG | ICANON;
784 if (flags & 0x02) { /* cbreak */
785 termios->c_iflag = 0;
786 termios->c_lflag &= ~ICANON;
788 if (flags & 0x08) { /* echo */
789 termios->c_lflag |= ECHO | ECHOE | ECHOK |
790 ECHOCTL | ECHOKE | IEXTEN;
792 if (flags & 0x10) { /* crmod */
793 termios->c_oflag |= OPOST | ONLCR;
795 if (flags & 0x20) { /* raw */
796 termios->c_iflag = 0;
797 termios->c_lflag &= ~(ISIG | ICANON);
799 if (!(termios->c_lflag & ICANON)) {
800 termios->c_cc[VMIN] = 1;
801 termios->c_cc[VTIME] = 0;
806 * set_sgttyb - set legacy terminal values
807 * @tty: tty structure
808 * @sgttyb: pointer to old style terminal structure
810 * Updates a terminal from the legacy BSD style terminal information
813 * Locking: termios_rwsem
816 static int set_sgttyb(struct tty_struct *tty, struct sgttyb __user *sgttyb)
820 struct ktermios termios;
822 retval = tty_check_change(tty);
826 if (copy_from_user(&tmp, sgttyb, sizeof(tmp)))
829 down_write(&tty->termios_rwsem);
830 termios = tty->termios;
831 termios.c_cc[VERASE] = tmp.sg_erase;
832 termios.c_cc[VKILL] = tmp.sg_kill;
833 set_sgflags(&termios, tmp.sg_flags);
834 /* Try and encode into Bfoo format */
836 tty_termios_encode_baud_rate(&termios, termios.c_ispeed,
839 up_write(&tty->termios_rwsem);
840 tty_set_termios(tty, &termios);
846 static int get_tchars(struct tty_struct *tty, struct tchars __user *tchars)
850 down_read(&tty->termios_rwsem);
851 tmp.t_intrc = tty->termios.c_cc[VINTR];
852 tmp.t_quitc = tty->termios.c_cc[VQUIT];
853 tmp.t_startc = tty->termios.c_cc[VSTART];
854 tmp.t_stopc = tty->termios.c_cc[VSTOP];
855 tmp.t_eofc = tty->termios.c_cc[VEOF];
856 tmp.t_brkc = tty->termios.c_cc[VEOL2]; /* what is brkc anyway? */
857 up_read(&tty->termios_rwsem);
858 return copy_to_user(tchars, &tmp, sizeof(tmp)) ? -EFAULT : 0;
861 static int set_tchars(struct tty_struct *tty, struct tchars __user *tchars)
865 if (copy_from_user(&tmp, tchars, sizeof(tmp)))
867 down_write(&tty->termios_rwsem);
868 tty->termios.c_cc[VINTR] = tmp.t_intrc;
869 tty->termios.c_cc[VQUIT] = tmp.t_quitc;
870 tty->termios.c_cc[VSTART] = tmp.t_startc;
871 tty->termios.c_cc[VSTOP] = tmp.t_stopc;
872 tty->termios.c_cc[VEOF] = tmp.t_eofc;
873 tty->termios.c_cc[VEOL2] = tmp.t_brkc; /* what is brkc anyway? */
874 up_write(&tty->termios_rwsem);
880 static int get_ltchars(struct tty_struct *tty, struct ltchars __user *ltchars)
884 down_read(&tty->termios_rwsem);
885 tmp.t_suspc = tty->termios.c_cc[VSUSP];
886 /* what is dsuspc anyway? */
887 tmp.t_dsuspc = tty->termios.c_cc[VSUSP];
888 tmp.t_rprntc = tty->termios.c_cc[VREPRINT];
889 /* what is flushc anyway? */
890 tmp.t_flushc = tty->termios.c_cc[VEOL2];
891 tmp.t_werasc = tty->termios.c_cc[VWERASE];
892 tmp.t_lnextc = tty->termios.c_cc[VLNEXT];
893 up_read(&tty->termios_rwsem);
894 return copy_to_user(ltchars, &tmp, sizeof(tmp)) ? -EFAULT : 0;
897 static int set_ltchars(struct tty_struct *tty, struct ltchars __user *ltchars)
901 if (copy_from_user(&tmp, ltchars, sizeof(tmp)))
904 down_write(&tty->termios_rwsem);
905 tty->termios.c_cc[VSUSP] = tmp.t_suspc;
906 /* what is dsuspc anyway? */
907 tty->termios.c_cc[VEOL2] = tmp.t_dsuspc;
908 tty->termios.c_cc[VREPRINT] = tmp.t_rprntc;
909 /* what is flushc anyway? */
910 tty->termios.c_cc[VEOL2] = tmp.t_flushc;
911 tty->termios.c_cc[VWERASE] = tmp.t_werasc;
912 tty->termios.c_cc[VLNEXT] = tmp.t_lnextc;
913 up_write(&tty->termios_rwsem);
919 * tty_change_softcar - carrier change ioctl helper
920 * @tty: tty to update
921 * @arg: enable/disable CLOCAL
923 * Perform a change to the CLOCAL state and call into the driver
924 * layer to make it visible. All done with the termios rwsem
927 static int tty_change_softcar(struct tty_struct *tty, int arg)
930 int bit = arg ? CLOCAL : 0;
933 down_write(&tty->termios_rwsem);
935 tty->termios.c_cflag &= ~CLOCAL;
936 tty->termios.c_cflag |= bit;
937 if (tty->ops->set_termios)
938 tty->ops->set_termios(tty, &old);
939 if ((tty->termios.c_cflag & CLOCAL) != bit)
941 up_write(&tty->termios_rwsem);
946 * tty_mode_ioctl - mode related ioctls
947 * @tty: tty for the ioctl
948 * @file: file pointer for the tty
950 * @arg: ioctl argument
952 * Perform non line discipline specific mode control ioctls. This
953 * is designed to be called by line disciplines to ensure they provide
954 * consistent mode setting.
957 int tty_mode_ioctl(struct tty_struct *tty, struct file *file,
958 unsigned int cmd, unsigned long arg)
960 struct tty_struct *real_tty;
961 void __user *p = (void __user *)arg;
963 struct ktermios kterm;
965 BUG_ON(file == NULL);
967 if (tty->driver->type == TTY_DRIVER_TYPE_PTY &&
968 tty->driver->subtype == PTY_TYPE_MASTER)
969 real_tty = tty->link;
976 return get_sgttyb(real_tty, (struct sgttyb __user *) arg);
979 return set_sgttyb(real_tty, (struct sgttyb __user *) arg);
983 return get_tchars(real_tty, p);
985 return set_tchars(real_tty, p);
989 return get_ltchars(real_tty, p);
991 return set_ltchars(real_tty, p);
994 return set_termios(real_tty, p, TERMIOS_FLUSH | TERMIOS_WAIT | TERMIOS_OLD);
996 return set_termios(real_tty, p, TERMIOS_WAIT | TERMIOS_OLD);
998 return set_termios(real_tty, p, TERMIOS_OLD);
1001 copy_termios(real_tty, &kterm);
1002 if (kernel_termios_to_user_termios((struct termios __user *)arg, &kterm))
1007 copy_termios(real_tty, &kterm);
1008 if (kernel_termios_to_user_termios_1((struct termios __user *)arg, &kterm))
1012 copy_termios(real_tty, &kterm);
1013 if (kernel_termios_to_user_termios((struct termios2 __user *)arg, &kterm))
1017 return set_termios(real_tty, p, TERMIOS_FLUSH | TERMIOS_WAIT);
1019 return set_termios(real_tty, p, TERMIOS_WAIT);
1021 return set_termios(real_tty, p, 0);
1024 return get_termio(real_tty, p);
1026 return set_termios(real_tty, p, TERMIOS_FLUSH | TERMIOS_WAIT | TERMIOS_TERMIO);
1028 return set_termios(real_tty, p, TERMIOS_WAIT | TERMIOS_TERMIO);
1030 return set_termios(real_tty, p, TERMIOS_TERMIO);
1032 case TIOCGLCKTRMIOS:
1033 copy_termios_locked(real_tty, &kterm);
1034 if (kernel_termios_to_user_termios((struct termios __user *)arg, &kterm))
1037 case TIOCSLCKTRMIOS:
1038 if (!capable(CAP_SYS_ADMIN))
1040 copy_termios_locked(real_tty, &kterm);
1041 if (user_termios_to_kernel_termios(&kterm,
1042 (struct termios __user *) arg))
1044 down_write(&real_tty->termios_rwsem);
1045 real_tty->termios_locked = kterm;
1046 up_write(&real_tty->termios_rwsem);
1049 case TIOCGLCKTRMIOS:
1050 copy_termios_locked(real_tty, &kterm);
1051 if (kernel_termios_to_user_termios_1((struct termios __user *)arg, &kterm))
1054 case TIOCSLCKTRMIOS:
1055 if (!capable(CAP_SYS_ADMIN))
1057 copy_termios_locked(real_tty, &kterm);
1058 if (user_termios_to_kernel_termios_1(&kterm,
1059 (struct termios __user *) arg))
1061 down_write(&real_tty->termios_rwsem);
1062 real_tty->termios_locked = kterm;
1063 up_write(&real_tty->termios_rwsem);
1068 struct termiox ktermx;
1069 if (real_tty->termiox == NULL)
1071 down_read(&real_tty->termios_rwsem);
1072 memcpy(&ktermx, real_tty->termiox, sizeof(struct termiox));
1073 up_read(&real_tty->termios_rwsem);
1074 if (copy_to_user(p, &ktermx, sizeof(struct termiox)))
1079 return set_termiox(real_tty, p, 0);
1081 return set_termiox(real_tty, p, TERMIOS_WAIT);
1083 return set_termiox(real_tty, p, TERMIOS_FLUSH);
1086 copy_termios(real_tty, &kterm);
1087 ret = put_user((kterm.c_cflag & CLOCAL) ? 1 : 0,
1091 if (get_user(arg, (unsigned int __user *) arg))
1093 return tty_change_softcar(real_tty, arg);
1095 return -ENOIOCTLCMD;
1098 EXPORT_SYMBOL_GPL(tty_mode_ioctl);
1101 /* Caller guarantees ldisc reference is held */
1102 static int __tty_perform_flush(struct tty_struct *tty, unsigned long arg)
1104 struct tty_ldisc *ld = tty->ldisc;
1108 if (ld && ld->ops->flush_buffer) {
1109 ld->ops->flush_buffer(tty);
1110 tty_unthrottle(tty);
1114 if (ld && ld->ops->flush_buffer) {
1115 ld->ops->flush_buffer(tty);
1116 tty_unthrottle(tty);
1120 tty_driver_flush_buffer(tty);
1128 int tty_perform_flush(struct tty_struct *tty, unsigned long arg)
1130 struct tty_ldisc *ld;
1131 int retval = tty_check_change(tty);
1135 ld = tty_ldisc_ref_wait(tty);
1136 retval = __tty_perform_flush(tty, arg);
1138 tty_ldisc_deref(ld);
1141 EXPORT_SYMBOL_GPL(tty_perform_flush);
1143 int n_tty_ioctl_helper(struct tty_struct *tty, struct file *file,
1144 unsigned int cmd, unsigned long arg)
1150 retval = tty_check_change(tty);
1155 spin_lock_irq(&tty->flow_lock);
1156 if (!tty->flow_stopped) {
1157 tty->flow_stopped = 1;
1160 spin_unlock_irq(&tty->flow_lock);
1163 spin_lock_irq(&tty->flow_lock);
1164 if (tty->flow_stopped) {
1165 tty->flow_stopped = 0;
1168 spin_unlock_irq(&tty->flow_lock);
1171 down_read(&tty->termios_rwsem);
1172 if (STOP_CHAR(tty) != __DISABLED_CHAR)
1173 retval = tty_send_xchar(tty, STOP_CHAR(tty));
1174 up_read(&tty->termios_rwsem);
1177 down_read(&tty->termios_rwsem);
1178 if (START_CHAR(tty) != __DISABLED_CHAR)
1179 retval = tty_send_xchar(tty, START_CHAR(tty));
1180 up_read(&tty->termios_rwsem);
1187 retval = tty_check_change(tty);
1190 return __tty_perform_flush(tty, arg);
1192 /* Try the mode commands */
1193 return tty_mode_ioctl(tty, file, cmd, arg);
1196 EXPORT_SYMBOL(n_tty_ioctl_helper);
1198 #ifdef CONFIG_COMPAT
1199 long n_tty_compat_ioctl_helper(struct tty_struct *tty, struct file *file,
1200 unsigned int cmd, unsigned long arg)
1203 case TIOCGLCKTRMIOS:
1204 case TIOCSLCKTRMIOS:
1205 return tty_mode_ioctl(tty, file, cmd, (unsigned long) compat_ptr(arg));
1207 return -ENOIOCTLCMD;
1210 EXPORT_SYMBOL(n_tty_compat_ioctl_helper);