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);
51 /* Review - krefs on tty_link ?? */
54 set_bit(TTY_OTHER_CLOSED, &tty->link->flags);
55 wake_up_interruptible(&tty->link->read_wait);
56 wake_up_interruptible(&tty->link->write_wait);
57 if (tty->driver->subtype == PTY_TYPE_MASTER) {
58 set_bit(TTY_OTHER_CLOSED, &tty->flags);
59 #ifdef CONFIG_UNIX98_PTYS
60 if (tty->driver == ptm_driver) {
61 mutex_lock(&devpts_mutex);
62 if (tty->link->driver_data)
63 devpts_pty_kill(tty->link->driver_data);
64 mutex_unlock(&devpts_mutex);
68 tty_vhangup(tty->link);
74 * The unthrottle routine is called by the line discipline to signal
75 * that it can receive more characters. For PTY's, the TTY_THROTTLED
76 * flag is always set, to force the line discipline to always call the
77 * unthrottle routine when there are fewer than TTY_THRESHOLD_UNTHROTTLE
78 * characters in the queue. This is necessary since each time this
79 * happens, we need to wake up any sleeping processes that could be
80 * (1) trying to send data to the pty, or (2) waiting in wait_until_sent()
81 * for the pty buffer to be drained.
83 static void pty_unthrottle(struct tty_struct *tty)
85 tty_wakeup(tty->link);
86 set_bit(TTY_THROTTLED, &tty->flags);
90 * pty_space - report space left for writing
91 * @to: tty we are writing into
93 * Limit the buffer space used by ptys to 8k.
96 static int pty_space(struct tty_struct *to)
98 int n = tty_buffer_space_avail(to->port);
103 * pty_write - write to a pty
104 * @tty: the tty we write from
105 * @buf: kernel buffer of data
106 * @count: bytes to write
108 * Our "hardware" write method. Data is coming from the ldisc which
109 * may be in a non sleeping state. We simply throw this at the other
110 * end of the link as if we were an IRQ handler receiving stuff for
111 * the other side of the pty/tty pair.
114 static int pty_write(struct tty_struct *tty, const unsigned char *buf, int c)
116 struct tty_struct *to = tty->link;
122 /* Stuff the data into the input queue of the other end */
123 c = tty_insert_flip_string(to->port, buf, c);
126 tty_flip_buffer_push(to->port);
132 * pty_write_room - write space
133 * @tty: tty we are writing from
135 * Report how many bytes the ldisc can send into the queue for
139 static int pty_write_room(struct tty_struct *tty)
143 return pty_space(tty->link);
147 * pty_chars_in_buffer - characters currently in our tx queue
150 * Report how much we have in the transmit queue. As everything is
151 * instantly at the other end this is easy to implement.
154 static int pty_chars_in_buffer(struct tty_struct *tty)
159 /* Set the lock flag on a pty */
160 static int pty_set_lock(struct tty_struct *tty, int __user *arg)
163 if (get_user(val, arg))
166 set_bit(TTY_PTY_LOCK, &tty->flags);
168 clear_bit(TTY_PTY_LOCK, &tty->flags);
172 static int pty_get_lock(struct tty_struct *tty, int __user *arg)
174 int locked = test_bit(TTY_PTY_LOCK, &tty->flags);
175 return put_user(locked, arg);
178 /* Set the packet mode on a pty */
179 static int pty_set_pktmode(struct tty_struct *tty, int __user *arg)
183 if (get_user(pktmode, arg))
186 spin_lock_irq(&tty->ctrl_lock);
190 tty->link->ctrl_status = 0;
194 spin_unlock_irq(&tty->ctrl_lock);
199 /* Get the packet mode of a pty */
200 static int pty_get_pktmode(struct tty_struct *tty, int __user *arg)
202 int pktmode = tty->packet;
203 return put_user(pktmode, arg);
206 /* Send a signal to the slave */
207 static int pty_signal(struct tty_struct *tty, int sig)
212 pgrp = tty_get_pgrp(tty->link);
214 kill_pgrp(pgrp, sig, 1);
220 static void pty_flush_buffer(struct tty_struct *tty)
222 struct tty_struct *to = tty->link;
226 /* tty_buffer_flush(to); FIXME */
228 spin_lock_irq(&tty->ctrl_lock);
229 tty->ctrl_status |= TIOCPKT_FLUSHWRITE;
230 wake_up_interruptible(&to->read_wait);
231 spin_unlock_irq(&tty->ctrl_lock);
235 static int pty_open(struct tty_struct *tty, struct file *filp)
237 if (!tty || !tty->link)
240 if (test_bit(TTY_OTHER_CLOSED, &tty->flags))
242 if (test_bit(TTY_PTY_LOCK, &tty->link->flags))
244 if (tty->driver->subtype == PTY_TYPE_SLAVE && tty->link->count != 1)
247 clear_bit(TTY_IO_ERROR, &tty->flags);
248 clear_bit(TTY_OTHER_CLOSED, &tty->link->flags);
249 set_bit(TTY_THROTTLED, &tty->flags);
253 set_bit(TTY_IO_ERROR, &tty->flags);
257 static void pty_set_termios(struct tty_struct *tty,
258 struct ktermios *old_termios)
260 /* See if packet mode change of state. */
261 if (tty->link && tty->link->packet) {
262 int extproc = (old_termios->c_lflag & EXTPROC) |
263 (tty->termios.c_lflag & EXTPROC);
264 int old_flow = ((old_termios->c_iflag & IXON) &&
265 (old_termios->c_cc[VSTOP] == '\023') &&
266 (old_termios->c_cc[VSTART] == '\021'));
267 int new_flow = (I_IXON(tty) &&
268 STOP_CHAR(tty) == '\023' &&
269 START_CHAR(tty) == '\021');
270 if ((old_flow != new_flow) || extproc) {
271 spin_lock_irq(&tty->ctrl_lock);
272 if (old_flow != new_flow) {
273 tty->ctrl_status &= ~(TIOCPKT_DOSTOP | TIOCPKT_NOSTOP);
275 tty->ctrl_status |= TIOCPKT_DOSTOP;
277 tty->ctrl_status |= TIOCPKT_NOSTOP;
280 tty->ctrl_status |= TIOCPKT_IOCTL;
281 spin_unlock_irq(&tty->ctrl_lock);
282 wake_up_interruptible(&tty->link->read_wait);
286 tty->termios.c_cflag &= ~(CSIZE | PARENB);
287 tty->termios.c_cflag |= (CS8 | CREAD);
291 * pty_do_resize - resize event
292 * @tty: tty being resized
293 * @ws: window size being set.
295 * Update the termios variables and send the necessary signals to
296 * peform a terminal resize correctly
299 static int pty_resize(struct tty_struct *tty, struct winsize *ws)
301 struct pid *pgrp, *rpgrp;
302 struct tty_struct *pty = tty->link;
304 /* For a PTY we need to lock the tty side */
305 mutex_lock(&tty->winsize_mutex);
306 if (!memcmp(ws, &tty->winsize, sizeof(*ws)))
309 /* Signal the foreground process group of both ptys */
310 pgrp = tty_get_pgrp(tty);
311 rpgrp = tty_get_pgrp(pty);
314 kill_pgrp(pgrp, SIGWINCH, 1);
315 if (rpgrp != pgrp && rpgrp)
316 kill_pgrp(rpgrp, SIGWINCH, 1);
322 pty->winsize = *ws; /* Never used so will go away soon */
324 mutex_unlock(&tty->winsize_mutex);
329 * pty_start - start() handler
330 * pty_stop - stop() handler
331 * @tty: tty being flow-controlled
333 * Propagates the TIOCPKT status to the master pty.
335 * NB: only the master pty can be in packet mode so only the slave
336 * needs start()/stop() handlers
338 static void pty_start(struct tty_struct *tty)
342 spin_lock_irqsave(&tty->ctrl_lock, flags);
343 if (tty->link && tty->link->packet) {
344 tty->ctrl_status &= ~TIOCPKT_STOP;
345 tty->ctrl_status |= TIOCPKT_START;
346 wake_up_interruptible_poll(&tty->link->read_wait, POLLIN);
348 spin_unlock_irqrestore(&tty->ctrl_lock, flags);
351 static void pty_stop(struct tty_struct *tty)
355 spin_lock_irqsave(&tty->ctrl_lock, flags);
356 if (tty->link && tty->link->packet) {
357 tty->ctrl_status &= ~TIOCPKT_START;
358 tty->ctrl_status |= TIOCPKT_STOP;
359 wake_up_interruptible_poll(&tty->link->read_wait, POLLIN);
361 spin_unlock_irqrestore(&tty->ctrl_lock, flags);
365 * pty_common_install - set up the pty pair
366 * @driver: the pty driver
367 * @tty: the tty being instantiated
368 * @legacy: true if this is BSD style
370 * Perform the initial set up for the tty/pty pair. Called from the
371 * tty layer when the port is first opened.
373 * Locking: the caller must hold the tty_mutex
375 static int pty_common_install(struct tty_driver *driver, struct tty_struct *tty,
378 struct tty_struct *o_tty;
379 struct tty_port *ports[2];
380 int idx = tty->index;
381 int retval = -ENOMEM;
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);
396 /* We always use new tty termios data so we can do this
398 retval = tty_init_termios(tty);
402 retval = tty_init_termios(o_tty);
404 goto err_free_termios;
406 driver->other->ttys[idx] = o_tty;
407 driver->ttys[idx] = tty;
409 memset(&tty->termios_locked, 0, sizeof(tty->termios_locked));
410 tty->termios = driver->init_termios;
411 memset(&o_tty->termios_locked, 0, sizeof(tty->termios_locked));
412 o_tty->termios = driver->other->init_termios;
416 * Everything allocated ... set up the o_tty structure.
418 tty_driver_kref_get(driver->other);
419 if (driver->subtype == PTY_TYPE_MASTER)
421 /* Establish the links in both directions */
424 tty_port_init(ports[0]);
425 tty_port_init(ports[1]);
426 o_tty->port = ports[0];
427 tty->port = ports[1];
428 o_tty->port->itty = o_tty;
430 tty_driver_kref_get(driver);
435 tty_free_termios(tty);
437 deinitialize_tty_struct(o_tty);
438 free_tty_struct(o_tty);
440 module_put(driver->other->owner);
447 static void pty_cleanup(struct tty_struct *tty)
449 tty_port_put(tty->port);
452 /* Traditional BSD devices */
453 #ifdef CONFIG_LEGACY_PTYS
455 static int pty_install(struct tty_driver *driver, struct tty_struct *tty)
457 return pty_common_install(driver, tty, true);
460 static void pty_remove(struct tty_driver *driver, struct tty_struct *tty)
462 struct tty_struct *pair = tty->link;
463 driver->ttys[tty->index] = NULL;
465 pair->driver->ttys[pair->index] = NULL;
468 static int pty_bsd_ioctl(struct tty_struct *tty,
469 unsigned int cmd, unsigned long arg)
472 case TIOCSPTLCK: /* Set PT Lock (disallow slave open) */
473 return pty_set_lock(tty, (int __user *) arg);
474 case TIOCGPTLCK: /* Get PT Lock status */
475 return pty_get_lock(tty, (int __user *)arg);
476 case TIOCPKT: /* Set PT packet mode */
477 return pty_set_pktmode(tty, (int __user *)arg);
478 case TIOCGPKT: /* Get PT packet mode */
479 return pty_get_pktmode(tty, (int __user *)arg);
480 case TIOCSIG: /* Send signal to other side of pty */
481 return pty_signal(tty, (int) arg);
482 case TIOCGPTN: /* TTY returns ENOTTY, but glibc expects EINVAL here */
488 static int legacy_count = CONFIG_LEGACY_PTY_COUNT;
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 inode *ptm_inode, 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 inode *pts_inode, int idx)
640 struct tty_struct *tty;
642 mutex_lock(&devpts_mutex);
643 tty = devpts_get_priv(pts_inode);
644 mutex_unlock(&devpts_mutex);
645 /* Master must be open before slave */
647 return ERR_PTR(-EIO);
651 /* We have no need to install and remove our tty objects as devpts does all
654 static int pty_unix98_install(struct tty_driver *driver, struct tty_struct *tty)
656 return pty_common_install(driver, tty, false);
659 static void pty_unix98_remove(struct tty_driver *driver, struct tty_struct *tty)
663 /* this is called once with whichever end is closed last */
664 static void pty_unix98_shutdown(struct tty_struct *tty)
666 devpts_kill_index(tty->driver_data, tty->index);
669 static const struct tty_operations ptm_unix98_ops = {
670 .lookup = ptm_unix98_lookup,
671 .install = pty_unix98_install,
672 .remove = pty_unix98_remove,
676 .write_room = pty_write_room,
677 .flush_buffer = pty_flush_buffer,
678 .chars_in_buffer = pty_chars_in_buffer,
679 .unthrottle = pty_unthrottle,
680 .ioctl = pty_unix98_ioctl,
681 .resize = pty_resize,
682 .shutdown = pty_unix98_shutdown,
683 .cleanup = pty_cleanup
686 static const struct tty_operations pty_unix98_ops = {
687 .lookup = pts_unix98_lookup,
688 .install = pty_unix98_install,
689 .remove = pty_unix98_remove,
693 .write_room = pty_write_room,
694 .flush_buffer = pty_flush_buffer,
695 .chars_in_buffer = pty_chars_in_buffer,
696 .unthrottle = pty_unthrottle,
697 .set_termios = pty_set_termios,
700 .shutdown = pty_unix98_shutdown,
701 .cleanup = pty_cleanup,
705 * ptmx_open - open a unix 98 pty master
706 * @inode: inode of device file
707 * @filp: file pointer to tty
709 * Allocate a unix98 pty master device from the ptmx driver.
711 * Locking: tty_mutex protects the init_dev work. tty->count should
713 * allocated_ptys_lock handles the list of free pty numbers
716 static int ptmx_open(struct inode *inode, struct file *filp)
718 struct tty_struct *tty;
719 struct inode *slave_inode;
723 nonseekable_open(inode, filp);
725 /* We refuse fsnotify events on ptmx, since it's a shared resource */
726 filp->f_mode |= FMODE_NONOTIFY;
728 retval = tty_alloc_file(filp);
732 /* find a device that is not in use. */
733 mutex_lock(&devpts_mutex);
734 index = devpts_new_index(inode);
737 mutex_unlock(&devpts_mutex);
741 mutex_unlock(&devpts_mutex);
743 mutex_lock(&tty_mutex);
744 tty = tty_init_dev(ptm_driver, index);
747 retval = PTR_ERR(tty);
751 /* The tty returned here is locked so we can safely
753 mutex_unlock(&tty_mutex);
755 set_bit(TTY_PTY_LOCK, &tty->flags); /* LOCK THE SLAVE */
756 tty->driver_data = inode;
758 tty_add_file(tty, filp);
760 slave_inode = devpts_pty_new(inode,
761 MKDEV(UNIX98_PTY_SLAVE_MAJOR, index), index,
763 if (IS_ERR(slave_inode)) {
764 retval = PTR_ERR(slave_inode);
767 tty->link->driver_data = slave_inode;
769 retval = ptm_driver->ops->open(tty, filp);
777 tty_release(inode, filp);
780 mutex_unlock(&tty_mutex);
781 devpts_kill_index(inode, index);
787 static struct file_operations ptmx_fops;
789 static void __init unix98_pty_init(void)
791 ptm_driver = tty_alloc_driver(NR_UNIX98_PTY_MAX,
792 TTY_DRIVER_RESET_TERMIOS |
793 TTY_DRIVER_REAL_RAW |
794 TTY_DRIVER_DYNAMIC_DEV |
795 TTY_DRIVER_DEVPTS_MEM |
796 TTY_DRIVER_DYNAMIC_ALLOC);
797 if (IS_ERR(ptm_driver))
798 panic("Couldn't allocate Unix98 ptm driver");
799 pts_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(pts_driver))
806 panic("Couldn't allocate Unix98 pts driver");
808 ptm_driver->driver_name = "pty_master";
809 ptm_driver->name = "ptm";
810 ptm_driver->major = UNIX98_PTY_MASTER_MAJOR;
811 ptm_driver->minor_start = 0;
812 ptm_driver->type = TTY_DRIVER_TYPE_PTY;
813 ptm_driver->subtype = PTY_TYPE_MASTER;
814 ptm_driver->init_termios = tty_std_termios;
815 ptm_driver->init_termios.c_iflag = 0;
816 ptm_driver->init_termios.c_oflag = 0;
817 ptm_driver->init_termios.c_cflag = B38400 | CS8 | CREAD;
818 ptm_driver->init_termios.c_lflag = 0;
819 ptm_driver->init_termios.c_ispeed = 38400;
820 ptm_driver->init_termios.c_ospeed = 38400;
821 ptm_driver->other = pts_driver;
822 tty_set_operations(ptm_driver, &ptm_unix98_ops);
824 pts_driver->driver_name = "pty_slave";
825 pts_driver->name = "pts";
826 pts_driver->major = UNIX98_PTY_SLAVE_MAJOR;
827 pts_driver->minor_start = 0;
828 pts_driver->type = TTY_DRIVER_TYPE_PTY;
829 pts_driver->subtype = PTY_TYPE_SLAVE;
830 pts_driver->init_termios = tty_std_termios;
831 pts_driver->init_termios.c_cflag = B38400 | CS8 | CREAD;
832 pts_driver->init_termios.c_ispeed = 38400;
833 pts_driver->init_termios.c_ospeed = 38400;
834 pts_driver->other = ptm_driver;
835 tty_set_operations(pts_driver, &pty_unix98_ops);
837 if (tty_register_driver(ptm_driver))
838 panic("Couldn't register Unix98 ptm driver");
839 if (tty_register_driver(pts_driver))
840 panic("Couldn't register Unix98 pts driver");
842 /* Now create the /dev/ptmx special device */
843 tty_default_fops(&ptmx_fops);
844 ptmx_fops.open = ptmx_open;
846 cdev_init(&ptmx_cdev, &ptmx_fops);
847 if (cdev_add(&ptmx_cdev, MKDEV(TTYAUX_MAJOR, 2), 1) ||
848 register_chrdev_region(MKDEV(TTYAUX_MAJOR, 2), 1, "/dev/ptmx") < 0)
849 panic("Couldn't register /dev/ptmx driver");
850 device_create(tty_class, NULL, MKDEV(TTYAUX_MAJOR, 2), NULL, "ptmx");
854 static inline void unix98_pty_init(void) { }
857 static int __init pty_init(void)
863 module_init(pty_init);