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>
10 #include <linux/errno.h>
11 #include <linux/interrupt.h>
12 #include <linux/tty.h>
13 #include <linux/tty_flip.h>
14 #include <linux/fcntl.h>
15 #include <linux/sched/signal.h>
16 #include <linux/string.h>
17 #include <linux/major.h>
19 #include <linux/init.h>
20 #include <linux/device.h>
21 #include <linux/uaccess.h>
22 #include <linux/bitops.h>
23 #include <linux/devpts_fs.h>
24 #include <linux/slab.h>
25 #include <linux/mutex.h>
26 #include <linux/poll.h>
28 #undef TTY_DEBUG_HANGUP
29 #ifdef TTY_DEBUG_HANGUP
30 # define tty_debug_hangup(tty, f, args...) tty_debug(tty, f, ##args)
32 # define tty_debug_hangup(tty, f, args...) do {} while (0)
35 #ifdef CONFIG_UNIX98_PTYS
36 static struct tty_driver *ptm_driver;
37 static struct tty_driver *pts_driver;
38 static DEFINE_MUTEX(devpts_mutex);
41 static void pty_close(struct tty_struct *tty, struct file *filp)
44 if (tty->driver->subtype == PTY_TYPE_MASTER)
45 WARN_ON(tty->count > 1);
47 if (tty_io_error(tty))
52 set_bit(TTY_IO_ERROR, &tty->flags);
53 wake_up_interruptible(&tty->read_wait);
54 wake_up_interruptible(&tty->write_wait);
55 spin_lock_irq(&tty->ctrl_lock);
57 spin_unlock_irq(&tty->ctrl_lock);
58 /* Review - krefs on tty_link ?? */
61 set_bit(TTY_OTHER_CLOSED, &tty->link->flags);
62 wake_up_interruptible(&tty->link->read_wait);
63 wake_up_interruptible(&tty->link->write_wait);
64 if (tty->driver->subtype == PTY_TYPE_MASTER) {
65 set_bit(TTY_OTHER_CLOSED, &tty->flags);
66 #ifdef CONFIG_UNIX98_PTYS
67 if (tty->driver == ptm_driver) {
68 mutex_lock(&devpts_mutex);
69 if (tty->link->driver_data)
70 devpts_pty_kill(tty->link->driver_data);
71 mutex_unlock(&devpts_mutex);
74 tty_vhangup(tty->link);
79 * The unthrottle routine is called by the line discipline to signal
80 * that it can receive more characters. For PTY's, the TTY_THROTTLED
81 * flag is always set, to force the line discipline to always call the
82 * unthrottle routine when there are fewer than TTY_THRESHOLD_UNTHROTTLE
83 * characters in the queue. This is necessary since each time this
84 * happens, we need to wake up any sleeping processes that could be
85 * (1) trying to send data to the pty, or (2) waiting in wait_until_sent()
86 * for the pty buffer to be drained.
88 static void pty_unthrottle(struct tty_struct *tty)
90 tty_wakeup(tty->link);
91 set_bit(TTY_THROTTLED, &tty->flags);
95 * pty_write - write to a pty
96 * @tty: the tty we write from
97 * @buf: kernel buffer of data
98 * @count: bytes to write
100 * Our "hardware" write method. Data is coming from the ldisc which
101 * may be in a non sleeping state. We simply throw this at the other
102 * end of the link as if we were an IRQ handler receiving stuff for
103 * the other side of the pty/tty pair.
106 static int pty_write(struct tty_struct *tty, const unsigned char *buf, int c)
108 struct tty_struct *to = tty->link;
114 /* Stuff the data into the input queue of the other end */
115 c = tty_insert_flip_string(to->port, buf, c);
118 tty_flip_buffer_push(to->port);
124 * pty_write_room - write space
125 * @tty: tty we are writing from
127 * Report how many bytes the ldisc can send into the queue for
131 static int pty_write_room(struct tty_struct *tty)
135 return tty_buffer_space_avail(tty->link->port);
139 * pty_chars_in_buffer - characters currently in our tx queue
142 * Report how much we have in the transmit queue. As everything is
143 * instantly at the other end this is easy to implement.
146 static int pty_chars_in_buffer(struct tty_struct *tty)
151 /* Set the lock flag on a pty */
152 static int pty_set_lock(struct tty_struct *tty, int __user *arg)
155 if (get_user(val, arg))
158 set_bit(TTY_PTY_LOCK, &tty->flags);
160 clear_bit(TTY_PTY_LOCK, &tty->flags);
164 static int pty_get_lock(struct tty_struct *tty, int __user *arg)
166 int locked = test_bit(TTY_PTY_LOCK, &tty->flags);
167 return put_user(locked, arg);
170 /* Set the packet mode on a pty */
171 static int pty_set_pktmode(struct tty_struct *tty, int __user *arg)
175 if (get_user(pktmode, arg))
178 spin_lock_irq(&tty->ctrl_lock);
181 tty->link->ctrl_status = 0;
187 spin_unlock_irq(&tty->ctrl_lock);
192 /* Get the packet mode of a pty */
193 static int pty_get_pktmode(struct tty_struct *tty, int __user *arg)
195 int pktmode = tty->packet;
196 return put_user(pktmode, arg);
199 /* Send a signal to the slave */
200 static int pty_signal(struct tty_struct *tty, int sig)
204 if (sig != SIGINT && sig != SIGQUIT && sig != SIGTSTP)
208 pgrp = tty_get_pgrp(tty->link);
210 kill_pgrp(pgrp, sig, 1);
216 static void pty_flush_buffer(struct tty_struct *tty)
218 struct tty_struct *to = tty->link;
223 tty_buffer_flush(to, NULL);
225 spin_lock_irq(&tty->ctrl_lock);
226 tty->ctrl_status |= TIOCPKT_FLUSHWRITE;
227 wake_up_interruptible(&to->read_wait);
228 spin_unlock_irq(&tty->ctrl_lock);
232 static int pty_open(struct tty_struct *tty, struct file *filp)
234 if (!tty || !tty->link)
237 if (test_bit(TTY_OTHER_CLOSED, &tty->flags))
239 if (test_bit(TTY_PTY_LOCK, &tty->link->flags))
241 if (tty->driver->subtype == PTY_TYPE_SLAVE && tty->link->count != 1)
244 clear_bit(TTY_IO_ERROR, &tty->flags);
245 clear_bit(TTY_OTHER_CLOSED, &tty->link->flags);
246 set_bit(TTY_THROTTLED, &tty->flags);
250 set_bit(TTY_IO_ERROR, &tty->flags);
254 static void pty_set_termios(struct tty_struct *tty,
255 struct ktermios *old_termios)
257 /* See if packet mode change of state. */
258 if (tty->link && tty->link->packet) {
259 int extproc = (old_termios->c_lflag & EXTPROC) | L_EXTPROC(tty);
260 int old_flow = ((old_termios->c_iflag & IXON) &&
261 (old_termios->c_cc[VSTOP] == '\023') &&
262 (old_termios->c_cc[VSTART] == '\021'));
263 int new_flow = (I_IXON(tty) &&
264 STOP_CHAR(tty) == '\023' &&
265 START_CHAR(tty) == '\021');
266 if ((old_flow != new_flow) || extproc) {
267 spin_lock_irq(&tty->ctrl_lock);
268 if (old_flow != new_flow) {
269 tty->ctrl_status &= ~(TIOCPKT_DOSTOP | TIOCPKT_NOSTOP);
271 tty->ctrl_status |= TIOCPKT_DOSTOP;
273 tty->ctrl_status |= TIOCPKT_NOSTOP;
276 tty->ctrl_status |= TIOCPKT_IOCTL;
277 spin_unlock_irq(&tty->ctrl_lock);
278 wake_up_interruptible(&tty->link->read_wait);
282 tty->termios.c_cflag &= ~(CSIZE | PARENB);
283 tty->termios.c_cflag |= (CS8 | CREAD);
287 * pty_do_resize - resize event
288 * @tty: tty being resized
289 * @ws: window size being set.
291 * Update the termios variables and send the necessary signals to
292 * peform a terminal resize correctly
295 static int pty_resize(struct tty_struct *tty, struct winsize *ws)
297 struct pid *pgrp, *rpgrp;
298 struct tty_struct *pty = tty->link;
300 /* For a PTY we need to lock the tty side */
301 mutex_lock(&tty->winsize_mutex);
302 if (!memcmp(ws, &tty->winsize, sizeof(*ws)))
305 /* Signal the foreground process group of both ptys */
306 pgrp = tty_get_pgrp(tty);
307 rpgrp = tty_get_pgrp(pty);
310 kill_pgrp(pgrp, SIGWINCH, 1);
311 if (rpgrp != pgrp && rpgrp)
312 kill_pgrp(rpgrp, SIGWINCH, 1);
318 pty->winsize = *ws; /* Never used so will go away soon */
320 mutex_unlock(&tty->winsize_mutex);
325 * pty_start - start() handler
326 * pty_stop - stop() handler
327 * @tty: tty being flow-controlled
329 * Propagates the TIOCPKT status to the master pty.
331 * NB: only the master pty can be in packet mode so only the slave
332 * needs start()/stop() handlers
334 static void pty_start(struct tty_struct *tty)
338 if (tty->link && tty->link->packet) {
339 spin_lock_irqsave(&tty->ctrl_lock, flags);
340 tty->ctrl_status &= ~TIOCPKT_STOP;
341 tty->ctrl_status |= TIOCPKT_START;
342 spin_unlock_irqrestore(&tty->ctrl_lock, flags);
343 wake_up_interruptible_poll(&tty->link->read_wait, POLLIN);
347 static void pty_stop(struct tty_struct *tty)
351 if (tty->link && tty->link->packet) {
352 spin_lock_irqsave(&tty->ctrl_lock, flags);
353 tty->ctrl_status &= ~TIOCPKT_START;
354 tty->ctrl_status |= TIOCPKT_STOP;
355 spin_unlock_irqrestore(&tty->ctrl_lock, flags);
356 wake_up_interruptible_poll(&tty->link->read_wait, POLLIN);
361 * pty_common_install - set up the pty pair
362 * @driver: the pty driver
363 * @tty: the tty being instantiated
364 * @legacy: true if this is BSD style
366 * Perform the initial set up for the tty/pty pair. Called from the
367 * tty layer when the port is first opened.
369 * Locking: the caller must hold the tty_mutex
371 static int pty_common_install(struct tty_driver *driver, struct tty_struct *tty,
374 struct tty_struct *o_tty;
375 struct tty_port *ports[2];
376 int idx = tty->index;
377 int retval = -ENOMEM;
379 /* Opening the slave first has always returned -EIO */
380 if (driver->subtype != PTY_TYPE_MASTER)
383 ports[0] = kmalloc(sizeof **ports, GFP_KERNEL);
384 ports[1] = kmalloc(sizeof **ports, GFP_KERNEL);
385 if (!ports[0] || !ports[1])
387 if (!try_module_get(driver->other->owner)) {
388 /* This cannot in fact currently happen */
391 o_tty = alloc_tty_struct(driver->other, idx);
395 tty_set_lock_subclass(o_tty);
396 lockdep_set_subclass(&o_tty->termios_rwsem, TTY_LOCK_SLAVE);
399 /* We always use new tty termios data so we can do this
401 tty_init_termios(tty);
402 tty_init_termios(o_tty);
404 driver->other->ttys[idx] = o_tty;
405 driver->ttys[idx] = tty;
407 memset(&tty->termios_locked, 0, sizeof(tty->termios_locked));
408 tty->termios = driver->init_termios;
409 memset(&o_tty->termios_locked, 0, sizeof(tty->termios_locked));
410 o_tty->termios = driver->other->init_termios;
414 * Everything allocated ... set up the o_tty structure.
416 tty_driver_kref_get(driver->other);
417 /* Establish the links in both directions */
420 tty_port_init(ports[0]);
421 tty_port_init(ports[1]);
422 tty_buffer_set_limit(ports[0], 8192);
423 tty_buffer_set_limit(ports[1], 8192);
424 o_tty->port = ports[0];
425 tty->port = ports[1];
426 o_tty->port->itty = o_tty;
428 tty_buffer_set_lock_subclass(o_tty->port);
430 tty_driver_kref_get(driver);
436 module_put(driver->other->owner);
443 static void pty_cleanup(struct tty_struct *tty)
445 tty_port_put(tty->port);
448 /* Traditional BSD devices */
449 #ifdef CONFIG_LEGACY_PTYS
451 static int pty_install(struct tty_driver *driver, struct tty_struct *tty)
453 return pty_common_install(driver, tty, true);
456 static void pty_remove(struct tty_driver *driver, struct tty_struct *tty)
458 struct tty_struct *pair = tty->link;
459 driver->ttys[tty->index] = NULL;
461 pair->driver->ttys[pair->index] = NULL;
464 static int pty_bsd_ioctl(struct tty_struct *tty,
465 unsigned int cmd, unsigned long arg)
468 case TIOCSPTLCK: /* Set PT Lock (disallow slave open) */
469 return pty_set_lock(tty, (int __user *) arg);
470 case TIOCGPTLCK: /* Get PT Lock status */
471 return pty_get_lock(tty, (int __user *)arg);
472 case TIOCPKT: /* Set PT packet mode */
473 return pty_set_pktmode(tty, (int __user *)arg);
474 case TIOCGPKT: /* Get PT packet mode */
475 return pty_get_pktmode(tty, (int __user *)arg);
476 case TIOCSIG: /* Send signal to other side of pty */
477 return pty_signal(tty, (int) arg);
478 case TIOCGPTN: /* TTY returns ENOTTY, but glibc expects EINVAL here */
484 static int legacy_count = CONFIG_LEGACY_PTY_COUNT;
486 * not really modular, but the easiest way to keep compat with existing
487 * bootargs behaviour is to continue using module_param here.
489 module_param(legacy_count, int, 0);
492 * The master side of a pty can do TIOCSPTLCK and thus
495 static const struct tty_operations master_pty_ops_bsd = {
496 .install = pty_install,
500 .write_room = pty_write_room,
501 .flush_buffer = pty_flush_buffer,
502 .chars_in_buffer = pty_chars_in_buffer,
503 .unthrottle = pty_unthrottle,
504 .ioctl = pty_bsd_ioctl,
505 .cleanup = pty_cleanup,
506 .resize = pty_resize,
510 static const struct tty_operations slave_pty_ops_bsd = {
511 .install = pty_install,
515 .write_room = pty_write_room,
516 .flush_buffer = pty_flush_buffer,
517 .chars_in_buffer = pty_chars_in_buffer,
518 .unthrottle = pty_unthrottle,
519 .set_termios = pty_set_termios,
520 .cleanup = pty_cleanup,
521 .resize = pty_resize,
527 static void __init legacy_pty_init(void)
529 struct tty_driver *pty_driver, *pty_slave_driver;
531 if (legacy_count <= 0)
534 pty_driver = tty_alloc_driver(legacy_count,
535 TTY_DRIVER_RESET_TERMIOS |
536 TTY_DRIVER_REAL_RAW |
537 TTY_DRIVER_DYNAMIC_ALLOC);
538 if (IS_ERR(pty_driver))
539 panic("Couldn't allocate pty driver");
541 pty_slave_driver = tty_alloc_driver(legacy_count,
542 TTY_DRIVER_RESET_TERMIOS |
543 TTY_DRIVER_REAL_RAW |
544 TTY_DRIVER_DYNAMIC_ALLOC);
545 if (IS_ERR(pty_slave_driver))
546 panic("Couldn't allocate pty slave driver");
548 pty_driver->driver_name = "pty_master";
549 pty_driver->name = "pty";
550 pty_driver->major = PTY_MASTER_MAJOR;
551 pty_driver->minor_start = 0;
552 pty_driver->type = TTY_DRIVER_TYPE_PTY;
553 pty_driver->subtype = PTY_TYPE_MASTER;
554 pty_driver->init_termios = tty_std_termios;
555 pty_driver->init_termios.c_iflag = 0;
556 pty_driver->init_termios.c_oflag = 0;
557 pty_driver->init_termios.c_cflag = B38400 | CS8 | CREAD;
558 pty_driver->init_termios.c_lflag = 0;
559 pty_driver->init_termios.c_ispeed = 38400;
560 pty_driver->init_termios.c_ospeed = 38400;
561 pty_driver->other = pty_slave_driver;
562 tty_set_operations(pty_driver, &master_pty_ops_bsd);
564 pty_slave_driver->driver_name = "pty_slave";
565 pty_slave_driver->name = "ttyp";
566 pty_slave_driver->major = PTY_SLAVE_MAJOR;
567 pty_slave_driver->minor_start = 0;
568 pty_slave_driver->type = TTY_DRIVER_TYPE_PTY;
569 pty_slave_driver->subtype = PTY_TYPE_SLAVE;
570 pty_slave_driver->init_termios = tty_std_termios;
571 pty_slave_driver->init_termios.c_cflag = B38400 | CS8 | CREAD;
572 pty_slave_driver->init_termios.c_ispeed = 38400;
573 pty_slave_driver->init_termios.c_ospeed = 38400;
574 pty_slave_driver->other = pty_driver;
575 tty_set_operations(pty_slave_driver, &slave_pty_ops_bsd);
577 if (tty_register_driver(pty_driver))
578 panic("Couldn't register pty driver");
579 if (tty_register_driver(pty_slave_driver))
580 panic("Couldn't register pty slave driver");
583 static inline void legacy_pty_init(void) { }
587 #ifdef CONFIG_UNIX98_PTYS
589 static struct cdev ptmx_cdev;
591 static int pty_unix98_ioctl(struct tty_struct *tty,
592 unsigned int cmd, unsigned long arg)
595 case TIOCSPTLCK: /* Set PT Lock (disallow slave open) */
596 return pty_set_lock(tty, (int __user *)arg);
597 case TIOCGPTLCK: /* Get PT Lock status */
598 return pty_get_lock(tty, (int __user *)arg);
599 case TIOCPKT: /* Set PT packet mode */
600 return pty_set_pktmode(tty, (int __user *)arg);
601 case TIOCGPKT: /* Get PT packet mode */
602 return pty_get_pktmode(tty, (int __user *)arg);
603 case TIOCGPTN: /* Get PT Number */
604 return put_user(tty->index, (unsigned int __user *)arg);
605 case TIOCSIG: /* Send signal to other side of pty */
606 return pty_signal(tty, (int) arg);
613 * ptm_unix98_lookup - find a pty master
614 * @driver: ptm driver
617 * Look up a pty master device. Called under the tty_mutex for now.
618 * This provides our locking.
621 static struct tty_struct *ptm_unix98_lookup(struct tty_driver *driver,
622 struct file *file, int idx)
624 /* Master must be open via /dev/ptmx */
625 return ERR_PTR(-EIO);
629 * pts_unix98_lookup - find a pty slave
630 * @driver: pts driver
633 * Look up a pty master device. Called under the tty_mutex for now.
634 * This provides our locking for the tty pointer.
637 static struct tty_struct *pts_unix98_lookup(struct tty_driver *driver,
638 struct file *file, int idx)
640 struct tty_struct *tty;
642 mutex_lock(&devpts_mutex);
643 tty = devpts_get_priv(file->f_path.dentry);
644 mutex_unlock(&devpts_mutex);
645 /* Master must be open before slave */
647 return ERR_PTR(-EIO);
651 static int pty_unix98_install(struct tty_driver *driver, struct tty_struct *tty)
653 return pty_common_install(driver, tty, false);
656 /* this is called once with whichever end is closed last */
657 static void pty_unix98_remove(struct tty_driver *driver, struct tty_struct *tty)
659 struct pts_fs_info *fsi;
661 if (tty->driver->subtype == PTY_TYPE_MASTER)
662 fsi = tty->driver_data;
664 fsi = tty->link->driver_data;
667 devpts_kill_index(fsi, tty->index);
672 static const struct tty_operations ptm_unix98_ops = {
673 .lookup = ptm_unix98_lookup,
674 .install = pty_unix98_install,
675 .remove = pty_unix98_remove,
679 .write_room = pty_write_room,
680 .flush_buffer = pty_flush_buffer,
681 .chars_in_buffer = pty_chars_in_buffer,
682 .unthrottle = pty_unthrottle,
683 .ioctl = pty_unix98_ioctl,
684 .resize = pty_resize,
685 .cleanup = pty_cleanup
688 static const struct tty_operations pty_unix98_ops = {
689 .lookup = pts_unix98_lookup,
690 .install = pty_unix98_install,
691 .remove = pty_unix98_remove,
695 .write_room = pty_write_room,
696 .flush_buffer = pty_flush_buffer,
697 .chars_in_buffer = pty_chars_in_buffer,
698 .unthrottle = pty_unthrottle,
699 .set_termios = pty_set_termios,
702 .cleanup = pty_cleanup,
706 * ptmx_open - open a unix 98 pty master
707 * @inode: inode of device file
708 * @filp: file pointer to tty
710 * Allocate a unix98 pty master device from the ptmx driver.
712 * Locking: tty_mutex protects the init_dev work. tty->count should
714 * allocated_ptys_lock handles the list of free pty numbers
717 static int ptmx_open(struct inode *inode, struct file *filp)
719 struct pts_fs_info *fsi;
720 struct tty_struct *tty;
721 struct dentry *dentry;
725 nonseekable_open(inode, filp);
727 /* We refuse fsnotify events on ptmx, since it's a shared resource */
728 filp->f_mode |= FMODE_NONOTIFY;
730 retval = tty_alloc_file(filp);
734 fsi = devpts_acquire(filp);
736 retval = PTR_ERR(fsi);
740 /* find a device that is not in use. */
741 mutex_lock(&devpts_mutex);
742 index = devpts_new_index(fsi);
743 mutex_unlock(&devpts_mutex);
750 mutex_lock(&tty_mutex);
751 tty = tty_init_dev(ptm_driver, index);
752 /* The tty returned here is locked so we can safely
754 mutex_unlock(&tty_mutex);
756 retval = PTR_ERR(tty);
761 * From here on out, the tty is "live", and the index and
762 * fsi will be killed/put by the tty_release()
764 set_bit(TTY_PTY_LOCK, &tty->flags); /* LOCK THE SLAVE */
765 tty->driver_data = fsi;
767 tty_add_file(tty, filp);
769 dentry = devpts_pty_new(fsi, index, tty->link);
770 if (IS_ERR(dentry)) {
771 retval = PTR_ERR(dentry);
774 tty->link->driver_data = dentry;
776 retval = ptm_driver->ops->open(tty, filp);
780 tty_debug_hangup(tty, "opening (count=%d)\n", tty->count);
786 // This will also put-ref the fsi
787 tty_release(inode, filp);
790 devpts_kill_index(fsi, index);
798 static struct file_operations ptmx_fops __ro_after_init;
800 static void __init unix98_pty_init(void)
802 ptm_driver = tty_alloc_driver(NR_UNIX98_PTY_MAX,
803 TTY_DRIVER_RESET_TERMIOS |
804 TTY_DRIVER_REAL_RAW |
805 TTY_DRIVER_DYNAMIC_DEV |
806 TTY_DRIVER_DEVPTS_MEM |
807 TTY_DRIVER_DYNAMIC_ALLOC);
808 if (IS_ERR(ptm_driver))
809 panic("Couldn't allocate Unix98 ptm driver");
810 pts_driver = tty_alloc_driver(NR_UNIX98_PTY_MAX,
811 TTY_DRIVER_RESET_TERMIOS |
812 TTY_DRIVER_REAL_RAW |
813 TTY_DRIVER_DYNAMIC_DEV |
814 TTY_DRIVER_DEVPTS_MEM |
815 TTY_DRIVER_DYNAMIC_ALLOC);
816 if (IS_ERR(pts_driver))
817 panic("Couldn't allocate Unix98 pts driver");
819 ptm_driver->driver_name = "pty_master";
820 ptm_driver->name = "ptm";
821 ptm_driver->major = UNIX98_PTY_MASTER_MAJOR;
822 ptm_driver->minor_start = 0;
823 ptm_driver->type = TTY_DRIVER_TYPE_PTY;
824 ptm_driver->subtype = PTY_TYPE_MASTER;
825 ptm_driver->init_termios = tty_std_termios;
826 ptm_driver->init_termios.c_iflag = 0;
827 ptm_driver->init_termios.c_oflag = 0;
828 ptm_driver->init_termios.c_cflag = B38400 | CS8 | CREAD;
829 ptm_driver->init_termios.c_lflag = 0;
830 ptm_driver->init_termios.c_ispeed = 38400;
831 ptm_driver->init_termios.c_ospeed = 38400;
832 ptm_driver->other = pts_driver;
833 tty_set_operations(ptm_driver, &ptm_unix98_ops);
835 pts_driver->driver_name = "pty_slave";
836 pts_driver->name = "pts";
837 pts_driver->major = UNIX98_PTY_SLAVE_MAJOR;
838 pts_driver->minor_start = 0;
839 pts_driver->type = TTY_DRIVER_TYPE_PTY;
840 pts_driver->subtype = PTY_TYPE_SLAVE;
841 pts_driver->init_termios = tty_std_termios;
842 pts_driver->init_termios.c_cflag = B38400 | CS8 | CREAD;
843 pts_driver->init_termios.c_ispeed = 38400;
844 pts_driver->init_termios.c_ospeed = 38400;
845 pts_driver->other = ptm_driver;
846 tty_set_operations(pts_driver, &pty_unix98_ops);
848 if (tty_register_driver(ptm_driver))
849 panic("Couldn't register Unix98 ptm driver");
850 if (tty_register_driver(pts_driver))
851 panic("Couldn't register Unix98 pts driver");
853 /* Now create the /dev/ptmx special device */
854 tty_default_fops(&ptmx_fops);
855 ptmx_fops.open = ptmx_open;
857 cdev_init(&ptmx_cdev, &ptmx_fops);
858 if (cdev_add(&ptmx_cdev, MKDEV(TTYAUX_MAJOR, 2), 1) ||
859 register_chrdev_region(MKDEV(TTYAUX_MAJOR, 2), 1, "/dev/ptmx") < 0)
860 panic("Couldn't register /dev/ptmx driver");
861 device_create(tty_class, NULL, MKDEV(TTYAUX_MAJOR, 2), NULL, "ptmx");
865 static inline void unix98_pty_init(void) { }
868 static int __init pty_init(void)
874 device_initcall(pty_init);