GUI: Fix Tomato RAF theme for all builds. Compilation typo.
[tomato.git] / release / src-rt-6.x.4708 / linux / linux-2.6.36 / drivers / char / pty.c
blobc0184c009924bdc9acb378b3fb3333c88fa03a90
1 /*
2 * linux/drivers/char/pty.c
4 * Copyright (C) 1991, 1992 Linus Torvalds
6 * Added support for a Unix98-style ptmx device.
7 * -- C. Scott Ananian <cananian@alumni.princeton.edu>, 14-Jan-1998
9 * When reading this code see also fs/devpts. In particular note that the
10 * driver_data field is used by the devpts side as a binding to the devpts
11 * inode.
14 #include <linux/module.h>
16 #include <linux/errno.h>
17 #include <linux/interrupt.h>
18 #include <linux/tty.h>
19 #include <linux/tty_flip.h>
20 #include <linux/fcntl.h>
21 #include <linux/sched.h>
22 #include <linux/string.h>
23 #include <linux/major.h>
24 #include <linux/mm.h>
25 #include <linux/init.h>
26 #include <linux/smp_lock.h>
27 #include <linux/sysctl.h>
28 #include <linux/device.h>
29 #include <linux/uaccess.h>
30 #include <linux/bitops.h>
31 #include <linux/devpts_fs.h>
32 #include <linux/slab.h>
34 #include <asm/system.h>
36 #ifdef CONFIG_UNIX98_PTYS
37 static struct tty_driver *ptm_driver;
38 static struct tty_driver *pts_driver;
39 #endif
41 static void pty_close(struct tty_struct *tty, struct file *filp)
43 BUG_ON(!tty);
44 if (tty->driver->subtype == PTY_TYPE_MASTER)
45 WARN_ON(tty->count > 1);
46 else {
47 if (tty->count > 2)
48 return;
50 wake_up_interruptible(&tty->read_wait);
51 wake_up_interruptible(&tty->write_wait);
52 tty->packet = 0;
53 if (!tty->link)
54 return;
55 tty->link->packet = 0;
56 set_bit(TTY_OTHER_CLOSED, &tty->link->flags);
57 wake_up_interruptible(&tty->link->read_wait);
58 wake_up_interruptible(&tty->link->write_wait);
59 if (tty->driver->subtype == PTY_TYPE_MASTER) {
60 set_bit(TTY_OTHER_CLOSED, &tty->flags);
61 #ifdef CONFIG_UNIX98_PTYS
62 if (tty->driver == ptm_driver)
63 devpts_pty_kill(tty->link);
64 #endif
65 tty_unlock();
66 tty_vhangup(tty->link);
67 tty_lock();
72 * The unthrottle routine is called by the line discipline to signal
73 * that it can receive more characters. For PTY's, the TTY_THROTTLED
74 * flag is always set, to force the line discipline to always call the
75 * unthrottle routine when there are fewer than TTY_THRESHOLD_UNTHROTTLE
76 * characters in the queue. This is necessary since each time this
77 * happens, we need to wake up any sleeping processes that could be
78 * (1) trying to send data to the pty, or (2) waiting in wait_until_sent()
79 * for the pty buffer to be drained.
81 static void pty_unthrottle(struct tty_struct *tty)
83 tty_wakeup(tty->link);
84 set_bit(TTY_THROTTLED, &tty->flags);
87 /**
88 * pty_space - report space left for writing
89 * @to: tty we are writing into
91 * The tty buffers allow 64K but we sneak a peak and clip at 8K this
92 * allows a lot of overspill room for echo and other fun messes to
93 * be handled properly
96 static int pty_space(struct tty_struct *to)
98 int n = 8192 - to->buf.memory_used;
99 if (n < 0)
100 return 0;
101 return n;
105 * pty_write - write to a pty
106 * @tty: the tty we write from
107 * @buf: kernel buffer of data
108 * @count: bytes to write
110 * Our "hardware" write method. Data is coming from the ldisc which
111 * may be in a non sleeping state. We simply throw this at the other
112 * end of the link as if we were an IRQ handler receiving stuff for
113 * the other side of the pty/tty pair.
116 static int pty_write(struct tty_struct *tty, const unsigned char *buf, int c)
118 struct tty_struct *to = tty->link;
120 if (tty->stopped)
121 return 0;
123 if (c > 0) {
124 /* Stuff the data into the input queue of the other end */
125 c = tty_insert_flip_string(to, buf, c);
126 /* And shovel */
127 if (c) {
128 tty_flip_buffer_push(to);
129 tty_wakeup(tty);
132 return c;
136 * pty_write_room - write space
137 * @tty: tty we are writing from
139 * Report how many bytes the ldisc can send into the queue for
140 * the other device.
143 static int pty_write_room(struct tty_struct *tty)
145 if (tty->stopped)
146 return 0;
147 return pty_space(tty->link);
151 * pty_chars_in_buffer - characters currently in our tx queue
152 * @tty: our tty
154 * Report how much we have in the transmit queue. As everything is
155 * instantly at the other end this is easy to implement.
158 static int pty_chars_in_buffer(struct tty_struct *tty)
160 return 0;
163 /* Set the lock flag on a pty */
164 static int pty_set_lock(struct tty_struct *tty, int __user *arg)
166 int val;
167 if (get_user(val, arg))
168 return -EFAULT;
169 if (val)
170 set_bit(TTY_PTY_LOCK, &tty->flags);
171 else
172 clear_bit(TTY_PTY_LOCK, &tty->flags);
173 return 0;
176 /* Send a signal to the slave */
177 static int pty_signal(struct tty_struct *tty, int sig)
179 unsigned long flags;
180 struct pid *pgrp;
182 if (tty->link) {
183 spin_lock_irqsave(&tty->link->ctrl_lock, flags);
184 pgrp = get_pid(tty->link->pgrp);
185 spin_unlock_irqrestore(&tty->link->ctrl_lock, flags);
187 kill_pgrp(pgrp, sig, 1);
188 put_pid(pgrp);
190 return 0;
193 static void pty_flush_buffer(struct tty_struct *tty)
195 struct tty_struct *to = tty->link;
196 unsigned long flags;
198 if (!to)
199 return;
200 if (to->packet) {
201 spin_lock_irqsave(&tty->ctrl_lock, flags);
202 tty->ctrl_status |= TIOCPKT_FLUSHWRITE;
203 wake_up_interruptible(&to->read_wait);
204 spin_unlock_irqrestore(&tty->ctrl_lock, flags);
208 static int pty_open(struct tty_struct *tty, struct file *filp)
210 int retval = -ENODEV;
212 if (!tty || !tty->link)
213 goto out;
215 retval = -EIO;
216 if (test_bit(TTY_OTHER_CLOSED, &tty->flags))
217 goto out;
218 if (test_bit(TTY_PTY_LOCK, &tty->link->flags))
219 goto out;
220 if (tty->link->count != 1)
221 goto out;
223 clear_bit(TTY_OTHER_CLOSED, &tty->link->flags);
224 set_bit(TTY_THROTTLED, &tty->flags);
225 retval = 0;
226 out:
227 return retval;
230 static void pty_set_termios(struct tty_struct *tty,
231 struct ktermios *old_termios)
233 tty->termios->c_cflag &= ~(CSIZE | PARENB);
234 tty->termios->c_cflag |= (CS8 | CREAD);
238 * pty_do_resize - resize event
239 * @tty: tty being resized
240 * @ws: window size being set.
242 * Update the termios variables and send the necessary signals to
243 * peform a terminal resize correctly
246 int pty_resize(struct tty_struct *tty, struct winsize *ws)
248 struct pid *pgrp, *rpgrp;
249 unsigned long flags;
250 struct tty_struct *pty = tty->link;
252 /* For a PTY we need to lock the tty side */
253 mutex_lock(&tty->termios_mutex);
254 if (!memcmp(ws, &tty->winsize, sizeof(*ws)))
255 goto done;
257 /* Get the PID values and reference them so we can
258 avoid holding the tty ctrl lock while sending signals.
259 We need to lock these individually however. */
261 spin_lock_irqsave(&tty->ctrl_lock, flags);
262 pgrp = get_pid(tty->pgrp);
263 spin_unlock_irqrestore(&tty->ctrl_lock, flags);
265 spin_lock_irqsave(&pty->ctrl_lock, flags);
266 rpgrp = get_pid(pty->pgrp);
267 spin_unlock_irqrestore(&pty->ctrl_lock, flags);
269 if (pgrp)
270 kill_pgrp(pgrp, SIGWINCH, 1);
271 if (rpgrp != pgrp && rpgrp)
272 kill_pgrp(rpgrp, SIGWINCH, 1);
274 put_pid(pgrp);
275 put_pid(rpgrp);
277 tty->winsize = *ws;
278 pty->winsize = *ws; /* Never used so will go away soon */
279 done:
280 mutex_unlock(&tty->termios_mutex);
281 return 0;
284 /* Traditional BSD devices */
285 #ifdef CONFIG_LEGACY_PTYS
287 static int pty_install(struct tty_driver *driver, struct tty_struct *tty)
289 struct tty_struct *o_tty;
290 int idx = tty->index;
291 int retval;
293 o_tty = alloc_tty_struct();
294 if (!o_tty)
295 return -ENOMEM;
296 if (!try_module_get(driver->other->owner)) {
297 /* This cannot in fact currently happen */
298 free_tty_struct(o_tty);
299 return -ENOMEM;
301 initialize_tty_struct(o_tty, driver->other, idx);
303 /* We always use new tty termios data so we can do this
304 the easy way .. */
305 retval = tty_init_termios(tty);
306 if (retval)
307 goto free_mem_out;
309 retval = tty_init_termios(o_tty);
310 if (retval) {
311 tty_free_termios(tty);
312 goto free_mem_out;
316 * Everything allocated ... set up the o_tty structure.
318 driver->other->ttys[idx] = o_tty;
319 tty_driver_kref_get(driver->other);
320 if (driver->subtype == PTY_TYPE_MASTER)
321 o_tty->count++;
322 /* Establish the links in both directions */
323 tty->link = o_tty;
324 o_tty->link = tty;
326 tty_driver_kref_get(driver);
327 tty->count++;
328 driver->ttys[idx] = tty;
329 return 0;
330 free_mem_out:
331 module_put(o_tty->driver->owner);
332 free_tty_struct(o_tty);
333 return -ENOMEM;
336 static int pty_bsd_ioctl(struct tty_struct *tty, struct file *file,
337 unsigned int cmd, unsigned long arg)
339 switch (cmd) {
340 case TIOCSPTLCK: /* Set PT Lock (disallow slave open) */
341 return pty_set_lock(tty, (int __user *) arg);
342 case TIOCSIG: /* Send signal to other side of pty */
343 return pty_signal(tty, (int) arg);
345 return -ENOIOCTLCMD;
348 static int legacy_count = CONFIG_LEGACY_PTY_COUNT;
349 module_param(legacy_count, int, 0);
352 * The master side of a pty can do TIOCSPTLCK and thus
353 * has pty_bsd_ioctl.
355 static const struct tty_operations master_pty_ops_bsd = {
356 .install = pty_install,
357 .open = pty_open,
358 .close = pty_close,
359 .write = pty_write,
360 .write_room = pty_write_room,
361 .flush_buffer = pty_flush_buffer,
362 .chars_in_buffer = pty_chars_in_buffer,
363 .unthrottle = pty_unthrottle,
364 .set_termios = pty_set_termios,
365 .ioctl = pty_bsd_ioctl,
366 .resize = pty_resize
369 static const struct tty_operations slave_pty_ops_bsd = {
370 .install = pty_install,
371 .open = pty_open,
372 .close = pty_close,
373 .write = pty_write,
374 .write_room = pty_write_room,
375 .flush_buffer = pty_flush_buffer,
376 .chars_in_buffer = pty_chars_in_buffer,
377 .unthrottle = pty_unthrottle,
378 .set_termios = pty_set_termios,
379 .resize = pty_resize
382 static void __init legacy_pty_init(void)
384 struct tty_driver *pty_driver, *pty_slave_driver;
386 if (legacy_count <= 0)
387 return;
389 pty_driver = alloc_tty_driver(legacy_count);
390 if (!pty_driver)
391 panic("Couldn't allocate pty driver");
393 pty_slave_driver = alloc_tty_driver(legacy_count);
394 if (!pty_slave_driver)
395 panic("Couldn't allocate pty slave driver");
397 pty_driver->owner = THIS_MODULE;
398 pty_driver->driver_name = "pty_master";
399 pty_driver->name = "pty";
400 pty_driver->major = PTY_MASTER_MAJOR;
401 pty_driver->minor_start = 0;
402 pty_driver->type = TTY_DRIVER_TYPE_PTY;
403 pty_driver->subtype = PTY_TYPE_MASTER;
404 pty_driver->init_termios = tty_std_termios;
405 pty_driver->init_termios.c_iflag = 0;
406 pty_driver->init_termios.c_oflag = 0;
407 pty_driver->init_termios.c_cflag = B38400 | CS8 | CREAD;
408 pty_driver->init_termios.c_lflag = 0;
409 pty_driver->init_termios.c_ispeed = 38400;
410 pty_driver->init_termios.c_ospeed = 38400;
411 pty_driver->flags = TTY_DRIVER_RESET_TERMIOS | TTY_DRIVER_REAL_RAW;
412 pty_driver->other = pty_slave_driver;
413 tty_set_operations(pty_driver, &master_pty_ops_bsd);
415 pty_slave_driver->owner = THIS_MODULE;
416 pty_slave_driver->driver_name = "pty_slave";
417 pty_slave_driver->name = "ttyp";
418 pty_slave_driver->major = PTY_SLAVE_MAJOR;
419 pty_slave_driver->minor_start = 0;
420 pty_slave_driver->type = TTY_DRIVER_TYPE_PTY;
421 pty_slave_driver->subtype = PTY_TYPE_SLAVE;
422 pty_slave_driver->init_termios = tty_std_termios;
423 pty_slave_driver->init_termios.c_cflag = B38400 | CS8 | CREAD;
424 pty_slave_driver->init_termios.c_ispeed = 38400;
425 pty_slave_driver->init_termios.c_ospeed = 38400;
426 pty_slave_driver->flags = TTY_DRIVER_RESET_TERMIOS |
427 TTY_DRIVER_REAL_RAW;
428 pty_slave_driver->other = pty_driver;
429 tty_set_operations(pty_slave_driver, &slave_pty_ops_bsd);
431 if (tty_register_driver(pty_driver))
432 panic("Couldn't register pty driver");
433 if (tty_register_driver(pty_slave_driver))
434 panic("Couldn't register pty slave driver");
436 #else
437 static inline void legacy_pty_init(void) { }
438 #endif
440 /* Unix98 devices */
441 #ifdef CONFIG_UNIX98_PTYS
443 * sysctl support for setting limits on the number of Unix98 ptys allocated.
444 * Otherwise one can eat up all kernel memory by opening /dev/ptmx repeatedly.
446 int pty_limit = NR_UNIX98_PTY_DEFAULT;
447 static int pty_limit_min;
448 static int pty_limit_max = NR_UNIX98_PTY_MAX;
449 static int pty_count;
451 static struct cdev ptmx_cdev;
453 static struct ctl_table pty_table[] = {
455 .procname = "max",
456 .maxlen = sizeof(int),
457 .mode = 0644,
458 .data = &pty_limit,
459 .proc_handler = proc_dointvec_minmax,
460 .extra1 = &pty_limit_min,
461 .extra2 = &pty_limit_max,
462 }, {
463 .procname = "nr",
464 .maxlen = sizeof(int),
465 .mode = 0444,
466 .data = &pty_count,
467 .proc_handler = proc_dointvec,
472 static struct ctl_table pty_kern_table[] = {
474 .procname = "pty",
475 .mode = 0555,
476 .child = pty_table,
481 static struct ctl_table pty_root_table[] = {
483 .procname = "kernel",
484 .mode = 0555,
485 .child = pty_kern_table,
491 static int pty_unix98_ioctl(struct tty_struct *tty, struct file *file,
492 unsigned int cmd, unsigned long arg)
494 switch (cmd) {
495 case TIOCSPTLCK: /* Set PT Lock (disallow slave open) */
496 return pty_set_lock(tty, (int __user *)arg);
497 case TIOCGPTN: /* Get PT Number */
498 return put_user(tty->index, (unsigned int __user *)arg);
499 case TIOCSIG: /* Send signal to other side of pty */
500 return pty_signal(tty, (int) arg);
503 return -ENOIOCTLCMD;
507 * ptm_unix98_lookup - find a pty master
508 * @driver: ptm driver
509 * @idx: tty index
511 * Look up a pty master device. Called under the tty_mutex for now.
512 * This provides our locking.
515 static struct tty_struct *ptm_unix98_lookup(struct tty_driver *driver,
516 struct inode *ptm_inode, int idx)
518 struct tty_struct *tty = devpts_get_tty(ptm_inode, idx);
519 if (tty)
520 tty = tty->link;
521 return tty;
525 * pts_unix98_lookup - find a pty slave
526 * @driver: pts driver
527 * @idx: tty index
529 * Look up a pty master device. Called under the tty_mutex for now.
530 * This provides our locking.
533 static struct tty_struct *pts_unix98_lookup(struct tty_driver *driver,
534 struct inode *pts_inode, int idx)
536 struct tty_struct *tty = devpts_get_tty(pts_inode, idx);
537 /* Master must be open before slave */
538 if (!tty)
539 return ERR_PTR(-EIO);
540 return tty;
543 static void pty_unix98_shutdown(struct tty_struct *tty)
545 /* We have our own method as we don't use the tty index */
546 kfree(tty->termios);
549 /* We have no need to install and remove our tty objects as devpts does all
550 the work for us */
552 static int pty_unix98_install(struct tty_driver *driver, struct tty_struct *tty)
554 struct tty_struct *o_tty;
555 int idx = tty->index;
557 o_tty = alloc_tty_struct();
558 if (!o_tty)
559 return -ENOMEM;
560 if (!try_module_get(driver->other->owner)) {
561 /* This cannot in fact currently happen */
562 free_tty_struct(o_tty);
563 return -ENOMEM;
565 initialize_tty_struct(o_tty, driver->other, idx);
567 tty->termios = kzalloc(sizeof(struct ktermios[2]), GFP_KERNEL);
568 if (tty->termios == NULL)
569 goto free_mem_out;
570 *tty->termios = driver->init_termios;
571 tty->termios_locked = tty->termios + 1;
573 o_tty->termios = kzalloc(sizeof(struct ktermios[2]), GFP_KERNEL);
574 if (o_tty->termios == NULL)
575 goto free_mem_out;
576 *o_tty->termios = driver->other->init_termios;
577 o_tty->termios_locked = o_tty->termios + 1;
579 tty_driver_kref_get(driver->other);
580 if (driver->subtype == PTY_TYPE_MASTER)
581 o_tty->count++;
582 /* Establish the links in both directions */
583 tty->link = o_tty;
584 o_tty->link = tty;
586 * All structures have been allocated, so now we install them.
587 * Failures after this point use release_tty to clean up, so
588 * there's no need to null out the local pointers.
590 tty_driver_kref_get(driver);
591 tty->count++;
592 pty_count++;
593 return 0;
594 free_mem_out:
595 kfree(o_tty->termios);
596 module_put(o_tty->driver->owner);
597 free_tty_struct(o_tty);
598 kfree(tty->termios);
599 return -ENOMEM;
602 static void pty_unix98_remove(struct tty_driver *driver, struct tty_struct *tty)
604 pty_count--;
607 static const struct tty_operations ptm_unix98_ops = {
608 .lookup = ptm_unix98_lookup,
609 .install = pty_unix98_install,
610 .remove = pty_unix98_remove,
611 .open = pty_open,
612 .close = pty_close,
613 .write = pty_write,
614 .write_room = pty_write_room,
615 .flush_buffer = pty_flush_buffer,
616 .chars_in_buffer = pty_chars_in_buffer,
617 .unthrottle = pty_unthrottle,
618 .set_termios = pty_set_termios,
619 .ioctl = pty_unix98_ioctl,
620 .shutdown = pty_unix98_shutdown,
621 .resize = pty_resize
624 static const struct tty_operations pty_unix98_ops = {
625 .lookup = pts_unix98_lookup,
626 .install = pty_unix98_install,
627 .remove = pty_unix98_remove,
628 .open = pty_open,
629 .close = pty_close,
630 .write = pty_write,
631 .write_room = pty_write_room,
632 .flush_buffer = pty_flush_buffer,
633 .chars_in_buffer = pty_chars_in_buffer,
634 .unthrottle = pty_unthrottle,
635 .set_termios = pty_set_termios,
636 .shutdown = pty_unix98_shutdown
640 * ptmx_open - open a unix 98 pty master
641 * @inode: inode of device file
642 * @filp: file pointer to tty
644 * Allocate a unix98 pty master device from the ptmx driver.
646 * Locking: tty_mutex protects the init_dev work. tty->count should
647 * protect the rest.
648 * allocated_ptys_lock handles the list of free pty numbers
651 static int ptmx_open(struct inode *inode, struct file *filp)
653 struct tty_struct *tty;
654 int retval;
655 int index;
657 nonseekable_open(inode, filp);
659 /* find a device that is not in use. */
660 tty_lock();
661 index = devpts_new_index(inode);
662 tty_unlock();
663 if (index < 0)
664 return index;
666 mutex_lock(&tty_mutex);
667 tty_lock();
668 tty = tty_init_dev(ptm_driver, index, 1);
669 mutex_unlock(&tty_mutex);
671 if (IS_ERR(tty)) {
672 retval = PTR_ERR(tty);
673 goto out;
676 set_bit(TTY_PTY_LOCK, &tty->flags); /* LOCK THE SLAVE */
678 tty_add_file(tty, filp);
680 retval = devpts_pty_new(inode, tty->link);
681 if (retval)
682 goto out1;
684 retval = ptm_driver->ops->open(tty, filp);
685 if (retval)
686 goto out2;
687 out1:
688 tty_unlock();
689 return retval;
690 out2:
691 tty_unlock();
692 tty_release(inode, filp);
693 return retval;
694 out:
695 devpts_kill_index(inode, index);
696 tty_unlock();
697 return retval;
700 static struct file_operations ptmx_fops;
702 static void __init unix98_pty_init(void)
704 ptm_driver = alloc_tty_driver(NR_UNIX98_PTY_MAX);
705 if (!ptm_driver)
706 panic("Couldn't allocate Unix98 ptm driver");
707 pts_driver = alloc_tty_driver(NR_UNIX98_PTY_MAX);
708 if (!pts_driver)
709 panic("Couldn't allocate Unix98 pts driver");
711 ptm_driver->owner = THIS_MODULE;
712 ptm_driver->driver_name = "pty_master";
713 ptm_driver->name = "ptm";
714 ptm_driver->major = UNIX98_PTY_MASTER_MAJOR;
715 ptm_driver->minor_start = 0;
716 ptm_driver->type = TTY_DRIVER_TYPE_PTY;
717 ptm_driver->subtype = PTY_TYPE_MASTER;
718 ptm_driver->init_termios = tty_std_termios;
719 ptm_driver->init_termios.c_iflag = 0;
720 ptm_driver->init_termios.c_oflag = 0;
721 ptm_driver->init_termios.c_cflag = B38400 | CS8 | CREAD;
722 ptm_driver->init_termios.c_lflag = 0;
723 ptm_driver->init_termios.c_ispeed = 38400;
724 ptm_driver->init_termios.c_ospeed = 38400;
725 ptm_driver->flags = TTY_DRIVER_RESET_TERMIOS | TTY_DRIVER_REAL_RAW |
726 TTY_DRIVER_DYNAMIC_DEV | TTY_DRIVER_DEVPTS_MEM;
727 ptm_driver->other = pts_driver;
728 tty_set_operations(ptm_driver, &ptm_unix98_ops);
730 pts_driver->owner = THIS_MODULE;
731 pts_driver->driver_name = "pty_slave";
732 pts_driver->name = "pts";
733 pts_driver->major = UNIX98_PTY_SLAVE_MAJOR;
734 pts_driver->minor_start = 0;
735 pts_driver->type = TTY_DRIVER_TYPE_PTY;
736 pts_driver->subtype = PTY_TYPE_SLAVE;
737 pts_driver->init_termios = tty_std_termios;
738 pts_driver->init_termios.c_cflag = B38400 | CS8 | CREAD;
739 pts_driver->init_termios.c_ispeed = 38400;
740 pts_driver->init_termios.c_ospeed = 38400;
741 pts_driver->flags = TTY_DRIVER_RESET_TERMIOS | TTY_DRIVER_REAL_RAW |
742 TTY_DRIVER_DYNAMIC_DEV | TTY_DRIVER_DEVPTS_MEM;
743 pts_driver->other = ptm_driver;
744 tty_set_operations(pts_driver, &pty_unix98_ops);
746 if (tty_register_driver(ptm_driver))
747 panic("Couldn't register Unix98 ptm driver");
748 if (tty_register_driver(pts_driver))
749 panic("Couldn't register Unix98 pts driver");
751 register_sysctl_table(pty_root_table);
753 /* Now create the /dev/ptmx special device */
754 tty_default_fops(&ptmx_fops);
755 ptmx_fops.open = ptmx_open;
757 cdev_init(&ptmx_cdev, &ptmx_fops);
758 if (cdev_add(&ptmx_cdev, MKDEV(TTYAUX_MAJOR, 2), 1) ||
759 register_chrdev_region(MKDEV(TTYAUX_MAJOR, 2), 1, "/dev/ptmx") < 0)
760 panic("Couldn't register /dev/ptmx driver\n");
761 device_create(tty_class, NULL, MKDEV(TTYAUX_MAJOR, 2), NULL, "ptmx");
764 #else
765 static inline void unix98_pty_init(void) { }
766 #endif
768 static int __init pty_init(void)
770 legacy_pty_init();
771 unix98_pty_init();
772 return 0;
774 module_init(pty_init);