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.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 (test_bit(TTY_IO_ERROR, &tty->flags))
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;
219 struct tty_ldisc *ld;
224 ld = tty_ldisc_ref(to);
225 tty_buffer_flush(to, ld);
230 spin_lock_irq(&tty->ctrl_lock);
231 tty->ctrl_status |= TIOCPKT_FLUSHWRITE;
232 wake_up_interruptible(&to->read_wait);
233 spin_unlock_irq(&tty->ctrl_lock);
237 static int pty_open(struct tty_struct *tty, struct file *filp)
239 if (!tty || !tty->link)
242 if (test_bit(TTY_OTHER_CLOSED, &tty->flags))
244 if (test_bit(TTY_PTY_LOCK, &tty->link->flags))
246 if (tty->driver->subtype == PTY_TYPE_SLAVE && tty->link->count != 1)
249 clear_bit(TTY_IO_ERROR, &tty->flags);
250 clear_bit(TTY_OTHER_CLOSED, &tty->link->flags);
251 set_bit(TTY_THROTTLED, &tty->flags);
255 set_bit(TTY_IO_ERROR, &tty->flags);
259 static void pty_set_termios(struct tty_struct *tty,
260 struct ktermios *old_termios)
262 /* See if packet mode change of state. */
263 if (tty->link && tty->link->packet) {
264 int extproc = (old_termios->c_lflag & EXTPROC) |
265 (tty->termios.c_lflag & EXTPROC);
266 int old_flow = ((old_termios->c_iflag & IXON) &&
267 (old_termios->c_cc[VSTOP] == '\023') &&
268 (old_termios->c_cc[VSTART] == '\021'));
269 int new_flow = (I_IXON(tty) &&
270 STOP_CHAR(tty) == '\023' &&
271 START_CHAR(tty) == '\021');
272 if ((old_flow != new_flow) || extproc) {
273 spin_lock_irq(&tty->ctrl_lock);
274 if (old_flow != new_flow) {
275 tty->ctrl_status &= ~(TIOCPKT_DOSTOP | TIOCPKT_NOSTOP);
277 tty->ctrl_status |= TIOCPKT_DOSTOP;
279 tty->ctrl_status |= TIOCPKT_NOSTOP;
282 tty->ctrl_status |= TIOCPKT_IOCTL;
283 spin_unlock_irq(&tty->ctrl_lock);
284 wake_up_interruptible(&tty->link->read_wait);
288 tty->termios.c_cflag &= ~(CSIZE | PARENB);
289 tty->termios.c_cflag |= (CS8 | CREAD);
293 * pty_do_resize - resize event
294 * @tty: tty being resized
295 * @ws: window size being set.
297 * Update the termios variables and send the necessary signals to
298 * peform a terminal resize correctly
301 static int pty_resize(struct tty_struct *tty, struct winsize *ws)
303 struct pid *pgrp, *rpgrp;
304 struct tty_struct *pty = tty->link;
306 /* For a PTY we need to lock the tty side */
307 mutex_lock(&tty->winsize_mutex);
308 if (!memcmp(ws, &tty->winsize, sizeof(*ws)))
311 /* Signal the foreground process group of both ptys */
312 pgrp = tty_get_pgrp(tty);
313 rpgrp = tty_get_pgrp(pty);
316 kill_pgrp(pgrp, SIGWINCH, 1);
317 if (rpgrp != pgrp && rpgrp)
318 kill_pgrp(rpgrp, SIGWINCH, 1);
324 pty->winsize = *ws; /* Never used so will go away soon */
326 mutex_unlock(&tty->winsize_mutex);
331 * pty_start - start() handler
332 * pty_stop - stop() handler
333 * @tty: tty being flow-controlled
335 * Propagates the TIOCPKT status to the master pty.
337 * NB: only the master pty can be in packet mode so only the slave
338 * needs start()/stop() handlers
340 static void pty_start(struct tty_struct *tty)
344 if (tty->link && tty->link->packet) {
345 spin_lock_irqsave(&tty->ctrl_lock, flags);
346 tty->ctrl_status &= ~TIOCPKT_STOP;
347 tty->ctrl_status |= TIOCPKT_START;
348 spin_unlock_irqrestore(&tty->ctrl_lock, flags);
349 wake_up_interruptible_poll(&tty->link->read_wait, POLLIN);
353 static void pty_stop(struct tty_struct *tty)
357 if (tty->link && tty->link->packet) {
358 spin_lock_irqsave(&tty->ctrl_lock, flags);
359 tty->ctrl_status &= ~TIOCPKT_START;
360 tty->ctrl_status |= TIOCPKT_STOP;
361 spin_unlock_irqrestore(&tty->ctrl_lock, flags);
362 wake_up_interruptible_poll(&tty->link->read_wait, POLLIN);
367 * pty_common_install - set up the pty pair
368 * @driver: the pty driver
369 * @tty: the tty being instantiated
370 * @legacy: true if this is BSD style
372 * Perform the initial set up for the tty/pty pair. Called from the
373 * tty layer when the port is first opened.
375 * Locking: the caller must hold the tty_mutex
377 static int pty_common_install(struct tty_driver *driver, struct tty_struct *tty,
380 struct tty_struct *o_tty;
381 struct tty_port *ports[2];
382 int idx = tty->index;
383 int retval = -ENOMEM;
385 /* Opening the slave first has always returned -EIO */
386 if (driver->subtype != PTY_TYPE_MASTER)
389 ports[0] = kmalloc(sizeof **ports, GFP_KERNEL);
390 ports[1] = kmalloc(sizeof **ports, GFP_KERNEL);
391 if (!ports[0] || !ports[1])
393 if (!try_module_get(driver->other->owner)) {
394 /* This cannot in fact currently happen */
397 o_tty = alloc_tty_struct(driver->other, idx);
401 tty_set_lock_subclass(o_tty);
402 lockdep_set_subclass(&o_tty->termios_rwsem, TTY_LOCK_SLAVE);
405 /* We always use new tty termios data so we can do this
407 retval = tty_init_termios(tty);
411 retval = tty_init_termios(o_tty);
413 goto err_free_termios;
415 driver->other->ttys[idx] = o_tty;
416 driver->ttys[idx] = tty;
418 memset(&tty->termios_locked, 0, sizeof(tty->termios_locked));
419 tty->termios = driver->init_termios;
420 memset(&o_tty->termios_locked, 0, sizeof(tty->termios_locked));
421 o_tty->termios = driver->other->init_termios;
425 * Everything allocated ... set up the o_tty structure.
427 tty_driver_kref_get(driver->other);
428 /* Establish the links in both directions */
431 tty_port_init(ports[0]);
432 tty_port_init(ports[1]);
433 tty_buffer_set_limit(ports[0], 8192);
434 tty_buffer_set_limit(ports[1], 8192);
435 o_tty->port = ports[0];
436 tty->port = ports[1];
437 o_tty->port->itty = o_tty;
439 tty_buffer_set_lock_subclass(o_tty->port);
441 tty_driver_kref_get(driver);
447 tty_free_termios(tty);
449 deinitialize_tty_struct(o_tty);
450 free_tty_struct(o_tty);
452 module_put(driver->other->owner);
459 static void pty_cleanup(struct tty_struct *tty)
461 tty_port_put(tty->port);
464 /* Traditional BSD devices */
465 #ifdef CONFIG_LEGACY_PTYS
467 static int pty_install(struct tty_driver *driver, struct tty_struct *tty)
469 return pty_common_install(driver, tty, true);
472 static void pty_remove(struct tty_driver *driver, struct tty_struct *tty)
474 struct tty_struct *pair = tty->link;
475 driver->ttys[tty->index] = NULL;
477 pair->driver->ttys[pair->index] = NULL;
480 static int pty_bsd_ioctl(struct tty_struct *tty,
481 unsigned int cmd, unsigned long arg)
484 case TIOCSPTLCK: /* Set PT Lock (disallow slave open) */
485 return pty_set_lock(tty, (int __user *) arg);
486 case TIOCGPTLCK: /* Get PT Lock status */
487 return pty_get_lock(tty, (int __user *)arg);
488 case TIOCPKT: /* Set PT packet mode */
489 return pty_set_pktmode(tty, (int __user *)arg);
490 case TIOCGPKT: /* Get PT packet mode */
491 return pty_get_pktmode(tty, (int __user *)arg);
492 case TIOCSIG: /* Send signal to other side of pty */
493 return pty_signal(tty, (int) arg);
494 case TIOCGPTN: /* TTY returns ENOTTY, but glibc expects EINVAL here */
500 static int legacy_count = CONFIG_LEGACY_PTY_COUNT;
502 * not really modular, but the easiest way to keep compat with existing
503 * bootargs behaviour is to continue using module_param here.
505 module_param(legacy_count, int, 0);
508 * The master side of a pty can do TIOCSPTLCK and thus
511 static const struct tty_operations master_pty_ops_bsd = {
512 .install = pty_install,
516 .write_room = pty_write_room,
517 .flush_buffer = pty_flush_buffer,
518 .chars_in_buffer = pty_chars_in_buffer,
519 .unthrottle = pty_unthrottle,
520 .ioctl = pty_bsd_ioctl,
521 .cleanup = pty_cleanup,
522 .resize = pty_resize,
526 static const struct tty_operations slave_pty_ops_bsd = {
527 .install = pty_install,
531 .write_room = pty_write_room,
532 .flush_buffer = pty_flush_buffer,
533 .chars_in_buffer = pty_chars_in_buffer,
534 .unthrottle = pty_unthrottle,
535 .set_termios = pty_set_termios,
536 .cleanup = pty_cleanup,
537 .resize = pty_resize,
543 static void __init legacy_pty_init(void)
545 struct tty_driver *pty_driver, *pty_slave_driver;
547 if (legacy_count <= 0)
550 pty_driver = tty_alloc_driver(legacy_count,
551 TTY_DRIVER_RESET_TERMIOS |
552 TTY_DRIVER_REAL_RAW |
553 TTY_DRIVER_DYNAMIC_ALLOC);
554 if (IS_ERR(pty_driver))
555 panic("Couldn't allocate pty driver");
557 pty_slave_driver = tty_alloc_driver(legacy_count,
558 TTY_DRIVER_RESET_TERMIOS |
559 TTY_DRIVER_REAL_RAW |
560 TTY_DRIVER_DYNAMIC_ALLOC);
561 if (IS_ERR(pty_slave_driver))
562 panic("Couldn't allocate pty slave driver");
564 pty_driver->driver_name = "pty_master";
565 pty_driver->name = "pty";
566 pty_driver->major = PTY_MASTER_MAJOR;
567 pty_driver->minor_start = 0;
568 pty_driver->type = TTY_DRIVER_TYPE_PTY;
569 pty_driver->subtype = PTY_TYPE_MASTER;
570 pty_driver->init_termios = tty_std_termios;
571 pty_driver->init_termios.c_iflag = 0;
572 pty_driver->init_termios.c_oflag = 0;
573 pty_driver->init_termios.c_cflag = B38400 | CS8 | CREAD;
574 pty_driver->init_termios.c_lflag = 0;
575 pty_driver->init_termios.c_ispeed = 38400;
576 pty_driver->init_termios.c_ospeed = 38400;
577 pty_driver->other = pty_slave_driver;
578 tty_set_operations(pty_driver, &master_pty_ops_bsd);
580 pty_slave_driver->driver_name = "pty_slave";
581 pty_slave_driver->name = "ttyp";
582 pty_slave_driver->major = PTY_SLAVE_MAJOR;
583 pty_slave_driver->minor_start = 0;
584 pty_slave_driver->type = TTY_DRIVER_TYPE_PTY;
585 pty_slave_driver->subtype = PTY_TYPE_SLAVE;
586 pty_slave_driver->init_termios = tty_std_termios;
587 pty_slave_driver->init_termios.c_cflag = B38400 | CS8 | CREAD;
588 pty_slave_driver->init_termios.c_ispeed = 38400;
589 pty_slave_driver->init_termios.c_ospeed = 38400;
590 pty_slave_driver->other = pty_driver;
591 tty_set_operations(pty_slave_driver, &slave_pty_ops_bsd);
593 if (tty_register_driver(pty_driver))
594 panic("Couldn't register pty driver");
595 if (tty_register_driver(pty_slave_driver))
596 panic("Couldn't register pty slave driver");
599 static inline void legacy_pty_init(void) { }
603 #ifdef CONFIG_UNIX98_PTYS
605 static struct cdev ptmx_cdev;
607 static int pty_unix98_ioctl(struct tty_struct *tty,
608 unsigned int cmd, unsigned long arg)
611 case TIOCSPTLCK: /* Set PT Lock (disallow slave open) */
612 return pty_set_lock(tty, (int __user *)arg);
613 case TIOCGPTLCK: /* Get PT Lock status */
614 return pty_get_lock(tty, (int __user *)arg);
615 case TIOCPKT: /* Set PT packet mode */
616 return pty_set_pktmode(tty, (int __user *)arg);
617 case TIOCGPKT: /* Get PT packet mode */
618 return pty_get_pktmode(tty, (int __user *)arg);
619 case TIOCGPTN: /* Get PT Number */
620 return put_user(tty->index, (unsigned int __user *)arg);
621 case TIOCSIG: /* Send signal to other side of pty */
622 return pty_signal(tty, (int) arg);
629 * ptm_unix98_lookup - find a pty master
630 * @driver: ptm driver
633 * Look up a pty master device. Called under the tty_mutex for now.
634 * This provides our locking.
637 static struct tty_struct *ptm_unix98_lookup(struct tty_driver *driver,
638 struct inode *ptm_inode, int idx)
640 /* Master must be open via /dev/ptmx */
641 return ERR_PTR(-EIO);
645 * pts_unix98_lookup - find a pty slave
646 * @driver: pts driver
649 * Look up a pty master device. Called under the tty_mutex for now.
650 * This provides our locking for the tty pointer.
653 static struct tty_struct *pts_unix98_lookup(struct tty_driver *driver,
654 struct inode *pts_inode, int idx)
656 struct tty_struct *tty;
658 mutex_lock(&devpts_mutex);
659 tty = devpts_get_priv(pts_inode);
660 mutex_unlock(&devpts_mutex);
661 /* Master must be open before slave */
663 return ERR_PTR(-EIO);
667 /* We have no need to install and remove our tty objects as devpts does all
670 static int pty_unix98_install(struct tty_driver *driver, struct tty_struct *tty)
672 return pty_common_install(driver, tty, false);
675 static void pty_unix98_remove(struct tty_driver *driver, struct tty_struct *tty)
679 /* this is called once with whichever end is closed last */
680 static void pty_unix98_shutdown(struct tty_struct *tty)
682 struct inode *ptmx_inode;
684 if (tty->driver->subtype == PTY_TYPE_MASTER)
685 ptmx_inode = tty->driver_data;
687 ptmx_inode = tty->link->driver_data;
688 devpts_kill_index(ptmx_inode, tty->index);
689 devpts_del_ref(ptmx_inode);
692 static const struct tty_operations ptm_unix98_ops = {
693 .lookup = ptm_unix98_lookup,
694 .install = pty_unix98_install,
695 .remove = pty_unix98_remove,
699 .write_room = pty_write_room,
700 .flush_buffer = pty_flush_buffer,
701 .chars_in_buffer = pty_chars_in_buffer,
702 .unthrottle = pty_unthrottle,
703 .ioctl = pty_unix98_ioctl,
704 .resize = pty_resize,
705 .shutdown = pty_unix98_shutdown,
706 .cleanup = pty_cleanup
709 static const struct tty_operations pty_unix98_ops = {
710 .lookup = pts_unix98_lookup,
711 .install = pty_unix98_install,
712 .remove = pty_unix98_remove,
716 .write_room = pty_write_room,
717 .flush_buffer = pty_flush_buffer,
718 .chars_in_buffer = pty_chars_in_buffer,
719 .unthrottle = pty_unthrottle,
720 .set_termios = pty_set_termios,
723 .shutdown = pty_unix98_shutdown,
724 .cleanup = pty_cleanup,
728 * ptmx_open - open a unix 98 pty master
729 * @inode: inode of device file
730 * @filp: file pointer to tty
732 * Allocate a unix98 pty master device from the ptmx driver.
734 * Locking: tty_mutex protects the init_dev work. tty->count should
736 * allocated_ptys_lock handles the list of free pty numbers
739 static int ptmx_open(struct inode *inode, struct file *filp)
741 struct tty_struct *tty;
742 struct inode *slave_inode;
746 nonseekable_open(inode, filp);
748 /* We refuse fsnotify events on ptmx, since it's a shared resource */
749 filp->f_mode |= FMODE_NONOTIFY;
751 retval = tty_alloc_file(filp);
755 /* find a device that is not in use. */
756 mutex_lock(&devpts_mutex);
757 index = devpts_new_index(inode);
760 mutex_unlock(&devpts_mutex);
764 mutex_unlock(&devpts_mutex);
766 mutex_lock(&tty_mutex);
767 tty = tty_init_dev(ptm_driver, index);
770 retval = PTR_ERR(tty);
774 /* The tty returned here is locked so we can safely
776 mutex_unlock(&tty_mutex);
778 set_bit(TTY_PTY_LOCK, &tty->flags); /* LOCK THE SLAVE */
779 tty->driver_data = inode;
782 * In the case where all references to ptmx inode are dropped and we
783 * still have /dev/tty opened pointing to the master/slave pair (ptmx
784 * is closed/released before /dev/tty), we must make sure that the inode
785 * is still valid when we call the final pty_unix98_shutdown, thus we
786 * hold an additional reference to the ptmx inode. For the same /dev/tty
787 * last close case, we also need to make sure the super_block isn't
788 * destroyed (devpts instance unmounted), before /dev/tty is closed and
789 * on its release devpts_kill_index is called.
791 devpts_add_ref(inode);
793 tty_add_file(tty, filp);
795 slave_inode = devpts_pty_new(inode,
796 MKDEV(UNIX98_PTY_SLAVE_MAJOR, index), index,
798 if (IS_ERR(slave_inode)) {
799 retval = PTR_ERR(slave_inode);
802 tty->link->driver_data = slave_inode;
804 retval = ptm_driver->ops->open(tty, filp);
808 tty_debug_hangup(tty, "(tty count=%d)\n", tty->count);
814 tty_release(inode, filp);
817 mutex_unlock(&tty_mutex);
818 devpts_kill_index(inode, index);
824 static struct file_operations ptmx_fops;
826 static void __init unix98_pty_init(void)
828 ptm_driver = tty_alloc_driver(NR_UNIX98_PTY_MAX,
829 TTY_DRIVER_RESET_TERMIOS |
830 TTY_DRIVER_REAL_RAW |
831 TTY_DRIVER_DYNAMIC_DEV |
832 TTY_DRIVER_DEVPTS_MEM |
833 TTY_DRIVER_DYNAMIC_ALLOC);
834 if (IS_ERR(ptm_driver))
835 panic("Couldn't allocate Unix98 ptm driver");
836 pts_driver = tty_alloc_driver(NR_UNIX98_PTY_MAX,
837 TTY_DRIVER_RESET_TERMIOS |
838 TTY_DRIVER_REAL_RAW |
839 TTY_DRIVER_DYNAMIC_DEV |
840 TTY_DRIVER_DEVPTS_MEM |
841 TTY_DRIVER_DYNAMIC_ALLOC);
842 if (IS_ERR(pts_driver))
843 panic("Couldn't allocate Unix98 pts driver");
845 ptm_driver->driver_name = "pty_master";
846 ptm_driver->name = "ptm";
847 ptm_driver->major = UNIX98_PTY_MASTER_MAJOR;
848 ptm_driver->minor_start = 0;
849 ptm_driver->type = TTY_DRIVER_TYPE_PTY;
850 ptm_driver->subtype = PTY_TYPE_MASTER;
851 ptm_driver->init_termios = tty_std_termios;
852 ptm_driver->init_termios.c_iflag = 0;
853 ptm_driver->init_termios.c_oflag = 0;
854 ptm_driver->init_termios.c_cflag = B38400 | CS8 | CREAD;
855 ptm_driver->init_termios.c_lflag = 0;
856 ptm_driver->init_termios.c_ispeed = 38400;
857 ptm_driver->init_termios.c_ospeed = 38400;
858 ptm_driver->other = pts_driver;
859 tty_set_operations(ptm_driver, &ptm_unix98_ops);
861 pts_driver->driver_name = "pty_slave";
862 pts_driver->name = "pts";
863 pts_driver->major = UNIX98_PTY_SLAVE_MAJOR;
864 pts_driver->minor_start = 0;
865 pts_driver->type = TTY_DRIVER_TYPE_PTY;
866 pts_driver->subtype = PTY_TYPE_SLAVE;
867 pts_driver->init_termios = tty_std_termios;
868 pts_driver->init_termios.c_cflag = B38400 | CS8 | CREAD;
869 pts_driver->init_termios.c_ispeed = 38400;
870 pts_driver->init_termios.c_ospeed = 38400;
871 pts_driver->other = ptm_driver;
872 tty_set_operations(pts_driver, &pty_unix98_ops);
874 if (tty_register_driver(ptm_driver))
875 panic("Couldn't register Unix98 ptm driver");
876 if (tty_register_driver(pts_driver))
877 panic("Couldn't register Unix98 pts driver");
879 /* Now create the /dev/ptmx special device */
880 tty_default_fops(&ptmx_fops);
881 ptmx_fops.open = ptmx_open;
883 cdev_init(&ptmx_cdev, &ptmx_fops);
884 if (cdev_add(&ptmx_cdev, MKDEV(TTYAUX_MAJOR, 2), 1) ||
885 register_chrdev_region(MKDEV(TTYAUX_MAJOR, 2), 1, "/dev/ptmx") < 0)
886 panic("Couldn't register /dev/ptmx driver");
887 device_create(tty_class, NULL, MKDEV(TTYAUX_MAJOR, 2), NULL, "ptmx");
891 static inline void unix98_pty_init(void) { }
894 static int __init pty_init(void)
900 device_initcall(pty_init);