2 * Copyright (C) 1991, 1992 Linus Torvalds
4 * Added support for a Unix98-style ptmx device.
5 * -- C. Scott Ananian <cananian@alumni.princeton.edu>, 14-Jan-1998
9 #include <linux/module.h>
11 #include <linux/errno.h>
12 #include <linux/interrupt.h>
13 #include <linux/tty.h>
14 #include <linux/tty_flip.h>
15 #include <linux/fcntl.h>
16 #include <linux/sched.h>
17 #include <linux/string.h>
18 #include <linux/major.h>
20 #include <linux/init.h>
21 #include <linux/device.h>
22 #include <linux/uaccess.h>
23 #include <linux/bitops.h>
24 #include <linux/devpts_fs.h>
25 #include <linux/slab.h>
26 #include <linux/mutex.h>
27 #include <linux/poll.h>
30 #ifdef CONFIG_UNIX98_PTYS
31 static struct tty_driver *ptm_driver;
32 static struct tty_driver *pts_driver;
33 static DEFINE_MUTEX(devpts_mutex);
36 static void pty_close(struct tty_struct *tty, struct file *filp)
39 if (tty->driver->subtype == PTY_TYPE_MASTER)
40 WARN_ON(tty->count > 1);
42 if (test_bit(TTY_IO_ERROR, &tty->flags))
47 set_bit(TTY_IO_ERROR, &tty->flags);
48 wake_up_interruptible(&tty->read_wait);
49 wake_up_interruptible(&tty->write_wait);
50 spin_lock_irq(&tty->ctrl_lock);
52 spin_unlock_irq(&tty->ctrl_lock);
53 /* Review - krefs on tty_link ?? */
56 tty_flush_to_ldisc(tty->link);
57 set_bit(TTY_OTHER_CLOSED, &tty->link->flags);
58 wake_up_interruptible(&tty->link->read_wait);
59 wake_up_interruptible(&tty->link->write_wait);
60 if (tty->driver->subtype == PTY_TYPE_MASTER) {
61 set_bit(TTY_OTHER_CLOSED, &tty->flags);
62 #ifdef CONFIG_UNIX98_PTYS
63 if (tty->driver == ptm_driver) {
64 mutex_lock(&devpts_mutex);
65 if (tty->link->driver_data)
66 devpts_pty_kill(tty->link->driver_data);
67 mutex_unlock(&devpts_mutex);
70 tty_vhangup(tty->link);
75 * The unthrottle routine is called by the line discipline to signal
76 * that it can receive more characters. For PTY's, the TTY_THROTTLED
77 * flag is always set, to force the line discipline to always call the
78 * unthrottle routine when there are fewer than TTY_THRESHOLD_UNTHROTTLE
79 * characters in the queue. This is necessary since each time this
80 * happens, we need to wake up any sleeping processes that could be
81 * (1) trying to send data to the pty, or (2) waiting in wait_until_sent()
82 * for the pty buffer to be drained.
84 static void pty_unthrottle(struct tty_struct *tty)
86 tty_wakeup(tty->link);
87 set_bit(TTY_THROTTLED, &tty->flags);
91 * pty_write - write to a pty
92 * @tty: the tty we write from
93 * @buf: kernel buffer of data
94 * @count: bytes to write
96 * Our "hardware" write method. Data is coming from the ldisc which
97 * may be in a non sleeping state. We simply throw this at the other
98 * end of the link as if we were an IRQ handler receiving stuff for
99 * the other side of the pty/tty pair.
102 static int pty_write(struct tty_struct *tty, const unsigned char *buf, int c)
104 struct tty_struct *to = tty->link;
110 /* Stuff the data into the input queue of the other end */
111 c = tty_insert_flip_string(to->port, buf, c);
114 tty_flip_buffer_push(to->port);
120 * pty_write_room - write space
121 * @tty: tty we are writing from
123 * Report how many bytes the ldisc can send into the queue for
127 static int pty_write_room(struct tty_struct *tty)
131 return tty_buffer_space_avail(tty->link->port);
135 * pty_chars_in_buffer - characters currently in our tx queue
138 * Report how much we have in the transmit queue. As everything is
139 * instantly at the other end this is easy to implement.
142 static int pty_chars_in_buffer(struct tty_struct *tty)
147 /* Set the lock flag on a pty */
148 static int pty_set_lock(struct tty_struct *tty, int __user *arg)
151 if (get_user(val, arg))
154 set_bit(TTY_PTY_LOCK, &tty->flags);
156 clear_bit(TTY_PTY_LOCK, &tty->flags);
160 static int pty_get_lock(struct tty_struct *tty, int __user *arg)
162 int locked = test_bit(TTY_PTY_LOCK, &tty->flags);
163 return put_user(locked, arg);
166 /* Set the packet mode on a pty */
167 static int pty_set_pktmode(struct tty_struct *tty, int __user *arg)
171 if (get_user(pktmode, arg))
174 spin_lock_irq(&tty->ctrl_lock);
177 tty->link->ctrl_status = 0;
183 spin_unlock_irq(&tty->ctrl_lock);
188 /* Get the packet mode of a pty */
189 static int pty_get_pktmode(struct tty_struct *tty, int __user *arg)
191 int pktmode = tty->packet;
192 return put_user(pktmode, arg);
195 /* Send a signal to the slave */
196 static int pty_signal(struct tty_struct *tty, int sig)
200 if (sig != SIGINT && sig != SIGQUIT && sig != SIGTSTP)
204 pgrp = tty_get_pgrp(tty->link);
206 kill_pgrp(pgrp, sig, 1);
212 static void pty_flush_buffer(struct tty_struct *tty)
214 struct tty_struct *to = tty->link;
215 struct tty_ldisc *ld;
220 ld = tty_ldisc_ref(to);
221 tty_buffer_flush(to, ld);
226 spin_lock_irq(&tty->ctrl_lock);
227 tty->ctrl_status |= TIOCPKT_FLUSHWRITE;
228 wake_up_interruptible(&to->read_wait);
229 spin_unlock_irq(&tty->ctrl_lock);
233 static int pty_open(struct tty_struct *tty, struct file *filp)
235 if (!tty || !tty->link)
238 if (test_bit(TTY_OTHER_CLOSED, &tty->flags))
240 if (test_bit(TTY_PTY_LOCK, &tty->link->flags))
242 if (tty->driver->subtype == PTY_TYPE_SLAVE && tty->link->count != 1)
245 clear_bit(TTY_IO_ERROR, &tty->flags);
246 clear_bit(TTY_OTHER_CLOSED, &tty->link->flags);
247 set_bit(TTY_THROTTLED, &tty->flags);
251 set_bit(TTY_IO_ERROR, &tty->flags);
255 static void pty_set_termios(struct tty_struct *tty,
256 struct ktermios *old_termios)
258 /* See if packet mode change of state. */
259 if (tty->link && tty->link->packet) {
260 int extproc = (old_termios->c_lflag & EXTPROC) |
261 (tty->termios.c_lflag & EXTPROC);
262 int old_flow = ((old_termios->c_iflag & IXON) &&
263 (old_termios->c_cc[VSTOP] == '\023') &&
264 (old_termios->c_cc[VSTART] == '\021'));
265 int new_flow = (I_IXON(tty) &&
266 STOP_CHAR(tty) == '\023' &&
267 START_CHAR(tty) == '\021');
268 if ((old_flow != new_flow) || extproc) {
269 spin_lock_irq(&tty->ctrl_lock);
270 if (old_flow != new_flow) {
271 tty->ctrl_status &= ~(TIOCPKT_DOSTOP | TIOCPKT_NOSTOP);
273 tty->ctrl_status |= TIOCPKT_DOSTOP;
275 tty->ctrl_status |= TIOCPKT_NOSTOP;
278 tty->ctrl_status |= TIOCPKT_IOCTL;
279 spin_unlock_irq(&tty->ctrl_lock);
280 wake_up_interruptible(&tty->link->read_wait);
284 tty->termios.c_cflag &= ~(CSIZE | PARENB);
285 tty->termios.c_cflag |= (CS8 | CREAD);
289 * pty_do_resize - resize event
290 * @tty: tty being resized
291 * @ws: window size being set.
293 * Update the termios variables and send the necessary signals to
294 * peform a terminal resize correctly
297 static int pty_resize(struct tty_struct *tty, struct winsize *ws)
299 struct pid *pgrp, *rpgrp;
300 struct tty_struct *pty = tty->link;
302 /* For a PTY we need to lock the tty side */
303 mutex_lock(&tty->winsize_mutex);
304 if (!memcmp(ws, &tty->winsize, sizeof(*ws)))
307 /* Signal the foreground process group of both ptys */
308 pgrp = tty_get_pgrp(tty);
309 rpgrp = tty_get_pgrp(pty);
312 kill_pgrp(pgrp, SIGWINCH, 1);
313 if (rpgrp != pgrp && rpgrp)
314 kill_pgrp(rpgrp, SIGWINCH, 1);
320 pty->winsize = *ws; /* Never used so will go away soon */
322 mutex_unlock(&tty->winsize_mutex);
327 * pty_start - start() handler
328 * pty_stop - stop() handler
329 * @tty: tty being flow-controlled
331 * Propagates the TIOCPKT status to the master pty.
333 * NB: only the master pty can be in packet mode so only the slave
334 * needs start()/stop() handlers
336 static void pty_start(struct tty_struct *tty)
340 if (tty->link && tty->link->packet) {
341 spin_lock_irqsave(&tty->ctrl_lock, flags);
342 tty->ctrl_status &= ~TIOCPKT_STOP;
343 tty->ctrl_status |= TIOCPKT_START;
344 spin_unlock_irqrestore(&tty->ctrl_lock, flags);
345 wake_up_interruptible_poll(&tty->link->read_wait, POLLIN);
349 static void pty_stop(struct tty_struct *tty)
353 if (tty->link && tty->link->packet) {
354 spin_lock_irqsave(&tty->ctrl_lock, flags);
355 tty->ctrl_status &= ~TIOCPKT_START;
356 tty->ctrl_status |= TIOCPKT_STOP;
357 spin_unlock_irqrestore(&tty->ctrl_lock, flags);
358 wake_up_interruptible_poll(&tty->link->read_wait, POLLIN);
363 * pty_common_install - set up the pty pair
364 * @driver: the pty driver
365 * @tty: the tty being instantiated
366 * @legacy: true if this is BSD style
368 * Perform the initial set up for the tty/pty pair. Called from the
369 * tty layer when the port is first opened.
371 * Locking: the caller must hold the tty_mutex
373 static int pty_common_install(struct tty_driver *driver, struct tty_struct *tty,
376 struct tty_struct *o_tty;
377 struct tty_port *ports[2];
378 int idx = tty->index;
379 int retval = -ENOMEM;
381 /* Opening the slave first has always returned -EIO */
382 if (driver->subtype != PTY_TYPE_MASTER)
385 ports[0] = kmalloc(sizeof **ports, GFP_KERNEL);
386 ports[1] = kmalloc(sizeof **ports, GFP_KERNEL);
387 if (!ports[0] || !ports[1])
389 if (!try_module_get(driver->other->owner)) {
390 /* This cannot in fact currently happen */
393 o_tty = alloc_tty_struct(driver->other, idx);
397 tty_set_lock_subclass(o_tty);
398 lockdep_set_subclass(&o_tty->termios_rwsem, TTY_LOCK_SLAVE);
401 /* We always use new tty termios data so we can do this
403 retval = tty_init_termios(tty);
407 retval = tty_init_termios(o_tty);
409 goto err_free_termios;
411 driver->other->ttys[idx] = o_tty;
412 driver->ttys[idx] = tty;
414 memset(&tty->termios_locked, 0, sizeof(tty->termios_locked));
415 tty->termios = driver->init_termios;
416 memset(&o_tty->termios_locked, 0, sizeof(tty->termios_locked));
417 o_tty->termios = driver->other->init_termios;
421 * Everything allocated ... set up the o_tty structure.
423 tty_driver_kref_get(driver->other);
424 /* Establish the links in both directions */
427 tty_port_init(ports[0]);
428 tty_port_init(ports[1]);
429 tty_buffer_set_limit(ports[0], 8192);
430 tty_buffer_set_limit(ports[1], 8192);
431 o_tty->port = ports[0];
432 tty->port = ports[1];
433 o_tty->port->itty = o_tty;
435 tty_buffer_set_lock_subclass(o_tty->port);
437 tty_driver_kref_get(driver);
443 tty_free_termios(tty);
445 deinitialize_tty_struct(o_tty);
446 free_tty_struct(o_tty);
448 module_put(driver->other->owner);
455 static void pty_cleanup(struct tty_struct *tty)
457 tty_port_put(tty->port);
460 /* Traditional BSD devices */
461 #ifdef CONFIG_LEGACY_PTYS
463 static int pty_install(struct tty_driver *driver, struct tty_struct *tty)
465 return pty_common_install(driver, tty, true);
468 static void pty_remove(struct tty_driver *driver, struct tty_struct *tty)
470 struct tty_struct *pair = tty->link;
471 driver->ttys[tty->index] = NULL;
473 pair->driver->ttys[pair->index] = NULL;
476 static int pty_bsd_ioctl(struct tty_struct *tty,
477 unsigned int cmd, unsigned long arg)
480 case TIOCSPTLCK: /* Set PT Lock (disallow slave open) */
481 return pty_set_lock(tty, (int __user *) arg);
482 case TIOCGPTLCK: /* Get PT Lock status */
483 return pty_get_lock(tty, (int __user *)arg);
484 case TIOCPKT: /* Set PT packet mode */
485 return pty_set_pktmode(tty, (int __user *)arg);
486 case TIOCGPKT: /* Get PT packet mode */
487 return pty_get_pktmode(tty, (int __user *)arg);
488 case TIOCSIG: /* Send signal to other side of pty */
489 return pty_signal(tty, (int) arg);
490 case TIOCGPTN: /* TTY returns ENOTTY, but glibc expects EINVAL here */
496 static int legacy_count = CONFIG_LEGACY_PTY_COUNT;
497 module_param(legacy_count, int, 0);
500 * The master side of a pty can do TIOCSPTLCK and thus
503 static const struct tty_operations master_pty_ops_bsd = {
504 .install = pty_install,
508 .write_room = pty_write_room,
509 .flush_buffer = pty_flush_buffer,
510 .chars_in_buffer = pty_chars_in_buffer,
511 .unthrottle = pty_unthrottle,
512 .ioctl = pty_bsd_ioctl,
513 .cleanup = pty_cleanup,
514 .resize = pty_resize,
518 static const struct tty_operations slave_pty_ops_bsd = {
519 .install = pty_install,
523 .write_room = pty_write_room,
524 .flush_buffer = pty_flush_buffer,
525 .chars_in_buffer = pty_chars_in_buffer,
526 .unthrottle = pty_unthrottle,
527 .set_termios = pty_set_termios,
528 .cleanup = pty_cleanup,
529 .resize = pty_resize,
535 static void __init legacy_pty_init(void)
537 struct tty_driver *pty_driver, *pty_slave_driver;
539 if (legacy_count <= 0)
542 pty_driver = tty_alloc_driver(legacy_count,
543 TTY_DRIVER_RESET_TERMIOS |
544 TTY_DRIVER_REAL_RAW |
545 TTY_DRIVER_DYNAMIC_ALLOC);
546 if (IS_ERR(pty_driver))
547 panic("Couldn't allocate pty driver");
549 pty_slave_driver = tty_alloc_driver(legacy_count,
550 TTY_DRIVER_RESET_TERMIOS |
551 TTY_DRIVER_REAL_RAW |
552 TTY_DRIVER_DYNAMIC_ALLOC);
553 if (IS_ERR(pty_slave_driver))
554 panic("Couldn't allocate pty slave driver");
556 pty_driver->driver_name = "pty_master";
557 pty_driver->name = "pty";
558 pty_driver->major = PTY_MASTER_MAJOR;
559 pty_driver->minor_start = 0;
560 pty_driver->type = TTY_DRIVER_TYPE_PTY;
561 pty_driver->subtype = PTY_TYPE_MASTER;
562 pty_driver->init_termios = tty_std_termios;
563 pty_driver->init_termios.c_iflag = 0;
564 pty_driver->init_termios.c_oflag = 0;
565 pty_driver->init_termios.c_cflag = B38400 | CS8 | CREAD;
566 pty_driver->init_termios.c_lflag = 0;
567 pty_driver->init_termios.c_ispeed = 38400;
568 pty_driver->init_termios.c_ospeed = 38400;
569 pty_driver->other = pty_slave_driver;
570 tty_set_operations(pty_driver, &master_pty_ops_bsd);
572 pty_slave_driver->driver_name = "pty_slave";
573 pty_slave_driver->name = "ttyp";
574 pty_slave_driver->major = PTY_SLAVE_MAJOR;
575 pty_slave_driver->minor_start = 0;
576 pty_slave_driver->type = TTY_DRIVER_TYPE_PTY;
577 pty_slave_driver->subtype = PTY_TYPE_SLAVE;
578 pty_slave_driver->init_termios = tty_std_termios;
579 pty_slave_driver->init_termios.c_cflag = B38400 | CS8 | CREAD;
580 pty_slave_driver->init_termios.c_ispeed = 38400;
581 pty_slave_driver->init_termios.c_ospeed = 38400;
582 pty_slave_driver->other = pty_driver;
583 tty_set_operations(pty_slave_driver, &slave_pty_ops_bsd);
585 if (tty_register_driver(pty_driver))
586 panic("Couldn't register pty driver");
587 if (tty_register_driver(pty_slave_driver))
588 panic("Couldn't register pty slave driver");
591 static inline void legacy_pty_init(void) { }
595 #ifdef CONFIG_UNIX98_PTYS
597 static struct cdev ptmx_cdev;
599 static int pty_unix98_ioctl(struct tty_struct *tty,
600 unsigned int cmd, unsigned long arg)
603 case TIOCSPTLCK: /* Set PT Lock (disallow slave open) */
604 return pty_set_lock(tty, (int __user *)arg);
605 case TIOCGPTLCK: /* Get PT Lock status */
606 return pty_get_lock(tty, (int __user *)arg);
607 case TIOCPKT: /* Set PT packet mode */
608 return pty_set_pktmode(tty, (int __user *)arg);
609 case TIOCGPKT: /* Get PT packet mode */
610 return pty_get_pktmode(tty, (int __user *)arg);
611 case TIOCGPTN: /* Get PT Number */
612 return put_user(tty->index, (unsigned int __user *)arg);
613 case TIOCSIG: /* Send signal to other side of pty */
614 return pty_signal(tty, (int) arg);
621 * ptm_unix98_lookup - find a pty master
622 * @driver: ptm driver
625 * Look up a pty master device. Called under the tty_mutex for now.
626 * This provides our locking.
629 static struct tty_struct *ptm_unix98_lookup(struct tty_driver *driver,
630 struct inode *ptm_inode, int idx)
632 /* Master must be open via /dev/ptmx */
633 return ERR_PTR(-EIO);
637 * pts_unix98_lookup - find a pty slave
638 * @driver: pts driver
641 * Look up a pty master device. Called under the tty_mutex for now.
642 * This provides our locking for the tty pointer.
645 static struct tty_struct *pts_unix98_lookup(struct tty_driver *driver,
646 struct inode *pts_inode, int idx)
648 struct tty_struct *tty;
650 mutex_lock(&devpts_mutex);
651 tty = devpts_get_priv(pts_inode);
652 mutex_unlock(&devpts_mutex);
653 /* Master must be open before slave */
655 return ERR_PTR(-EIO);
659 /* We have no need to install and remove our tty objects as devpts does all
662 static int pty_unix98_install(struct tty_driver *driver, struct tty_struct *tty)
664 return pty_common_install(driver, tty, false);
667 static void pty_unix98_remove(struct tty_driver *driver, struct tty_struct *tty)
671 /* this is called once with whichever end is closed last */
672 static void pty_unix98_shutdown(struct tty_struct *tty)
674 devpts_kill_index(tty->driver_data, tty->index);
677 static const struct tty_operations ptm_unix98_ops = {
678 .lookup = ptm_unix98_lookup,
679 .install = pty_unix98_install,
680 .remove = pty_unix98_remove,
684 .write_room = pty_write_room,
685 .flush_buffer = pty_flush_buffer,
686 .chars_in_buffer = pty_chars_in_buffer,
687 .unthrottle = pty_unthrottle,
688 .ioctl = pty_unix98_ioctl,
689 .resize = pty_resize,
690 .shutdown = pty_unix98_shutdown,
691 .cleanup = pty_cleanup
694 static const struct tty_operations pty_unix98_ops = {
695 .lookup = pts_unix98_lookup,
696 .install = pty_unix98_install,
697 .remove = pty_unix98_remove,
701 .write_room = pty_write_room,
702 .flush_buffer = pty_flush_buffer,
703 .chars_in_buffer = pty_chars_in_buffer,
704 .unthrottle = pty_unthrottle,
705 .set_termios = pty_set_termios,
708 .shutdown = pty_unix98_shutdown,
709 .cleanup = pty_cleanup,
713 * ptmx_open - open a unix 98 pty master
714 * @inode: inode of device file
715 * @filp: file pointer to tty
717 * Allocate a unix98 pty master device from the ptmx driver.
719 * Locking: tty_mutex protects the init_dev work. tty->count should
721 * allocated_ptys_lock handles the list of free pty numbers
724 static int ptmx_open(struct inode *inode, struct file *filp)
726 struct tty_struct *tty;
727 struct inode *slave_inode;
731 nonseekable_open(inode, filp);
733 /* We refuse fsnotify events on ptmx, since it's a shared resource */
734 filp->f_mode |= FMODE_NONOTIFY;
736 retval = tty_alloc_file(filp);
740 /* find a device that is not in use. */
741 mutex_lock(&devpts_mutex);
742 index = devpts_new_index(inode);
745 mutex_unlock(&devpts_mutex);
749 mutex_unlock(&devpts_mutex);
751 mutex_lock(&tty_mutex);
752 tty = tty_init_dev(ptm_driver, index);
755 retval = PTR_ERR(tty);
759 /* The tty returned here is locked so we can safely
761 mutex_unlock(&tty_mutex);
763 set_bit(TTY_PTY_LOCK, &tty->flags); /* LOCK THE SLAVE */
764 tty->driver_data = inode;
766 tty_add_file(tty, filp);
768 slave_inode = devpts_pty_new(inode,
769 MKDEV(UNIX98_PTY_SLAVE_MAJOR, index), index,
771 if (IS_ERR(slave_inode)) {
772 retval = PTR_ERR(slave_inode);
775 tty->link->driver_data = slave_inode;
777 retval = ptm_driver->ops->open(tty, filp);
785 tty_release(inode, filp);
788 mutex_unlock(&tty_mutex);
789 devpts_kill_index(inode, index);
795 static struct file_operations ptmx_fops;
797 static void __init unix98_pty_init(void)
799 ptm_driver = tty_alloc_driver(NR_UNIX98_PTY_MAX,
800 TTY_DRIVER_RESET_TERMIOS |
801 TTY_DRIVER_REAL_RAW |
802 TTY_DRIVER_DYNAMIC_DEV |
803 TTY_DRIVER_DEVPTS_MEM |
804 TTY_DRIVER_DYNAMIC_ALLOC);
805 if (IS_ERR(ptm_driver))
806 panic("Couldn't allocate Unix98 ptm driver");
807 pts_driver = tty_alloc_driver(NR_UNIX98_PTY_MAX,
808 TTY_DRIVER_RESET_TERMIOS |
809 TTY_DRIVER_REAL_RAW |
810 TTY_DRIVER_DYNAMIC_DEV |
811 TTY_DRIVER_DEVPTS_MEM |
812 TTY_DRIVER_DYNAMIC_ALLOC);
813 if (IS_ERR(pts_driver))
814 panic("Couldn't allocate Unix98 pts driver");
816 ptm_driver->driver_name = "pty_master";
817 ptm_driver->name = "ptm";
818 ptm_driver->major = UNIX98_PTY_MASTER_MAJOR;
819 ptm_driver->minor_start = 0;
820 ptm_driver->type = TTY_DRIVER_TYPE_PTY;
821 ptm_driver->subtype = PTY_TYPE_MASTER;
822 ptm_driver->init_termios = tty_std_termios;
823 ptm_driver->init_termios.c_iflag = 0;
824 ptm_driver->init_termios.c_oflag = 0;
825 ptm_driver->init_termios.c_cflag = B38400 | CS8 | CREAD;
826 ptm_driver->init_termios.c_lflag = 0;
827 ptm_driver->init_termios.c_ispeed = 38400;
828 ptm_driver->init_termios.c_ospeed = 38400;
829 ptm_driver->other = pts_driver;
830 tty_set_operations(ptm_driver, &ptm_unix98_ops);
832 pts_driver->driver_name = "pty_slave";
833 pts_driver->name = "pts";
834 pts_driver->major = UNIX98_PTY_SLAVE_MAJOR;
835 pts_driver->minor_start = 0;
836 pts_driver->type = TTY_DRIVER_TYPE_PTY;
837 pts_driver->subtype = PTY_TYPE_SLAVE;
838 pts_driver->init_termios = tty_std_termios;
839 pts_driver->init_termios.c_cflag = B38400 | CS8 | CREAD;
840 pts_driver->init_termios.c_ispeed = 38400;
841 pts_driver->init_termios.c_ospeed = 38400;
842 pts_driver->other = ptm_driver;
843 tty_set_operations(pts_driver, &pty_unix98_ops);
845 if (tty_register_driver(ptm_driver))
846 panic("Couldn't register Unix98 ptm driver");
847 if (tty_register_driver(pts_driver))
848 panic("Couldn't register Unix98 pts driver");
850 /* Now create the /dev/ptmx special device */
851 tty_default_fops(&ptmx_fops);
852 ptmx_fops.open = ptmx_open;
854 cdev_init(&ptmx_cdev, &ptmx_fops);
855 if (cdev_add(&ptmx_cdev, MKDEV(TTYAUX_MAJOR, 2), 1) ||
856 register_chrdev_region(MKDEV(TTYAUX_MAJOR, 2), 1, "/dev/ptmx") < 0)
857 panic("Couldn't register /dev/ptmx driver");
858 device_create(tty_class, NULL, MKDEV(TTYAUX_MAJOR, 2), NULL, "ptmx");
862 static inline void unix98_pty_init(void) { }
865 static int __init pty_init(void)
871 module_init(pty_init);