Remove all #inclusions of asm/system.h
[linux-2.6.git] / drivers / tty / pty.c
1 /*
2  *  Copyright (C) 1991, 1992  Linus Torvalds
3  *
4  *  Added support for a Unix98-style ptmx device.
5  *    -- C. Scott Ananian <cananian@alumni.princeton.edu>, 14-Jan-1998
6  *
7  *  When reading this code see also fs/devpts. In particular note that the
8  *  driver_data field is used by the devpts side as a binding to the devpts
9  *  inode.
10  */
11
12 #include <linux/module.h>
13
14 #include <linux/errno.h>
15 #include <linux/interrupt.h>
16 #include <linux/tty.h>
17 #include <linux/tty_flip.h>
18 #include <linux/fcntl.h>
19 #include <linux/sched.h>
20 #include <linux/string.h>
21 #include <linux/major.h>
22 #include <linux/mm.h>
23 #include <linux/init.h>
24 #include <linux/device.h>
25 #include <linux/uaccess.h>
26 #include <linux/bitops.h>
27 #include <linux/devpts_fs.h>
28 #include <linux/slab.h>
29
30
31 #ifdef CONFIG_UNIX98_PTYS
32 static struct tty_driver *ptm_driver;
33 static struct tty_driver *pts_driver;
34 #endif
35
36 static void pty_close(struct tty_struct *tty, struct file *filp)
37 {
38         BUG_ON(!tty);
39         if (tty->driver->subtype == PTY_TYPE_MASTER)
40                 WARN_ON(tty->count > 1);
41         else {
42                 if (tty->count > 2)
43                         return;
44         }
45         wake_up_interruptible(&tty->read_wait);
46         wake_up_interruptible(&tty->write_wait);
47         tty->packet = 0;
48         if (!tty->link)
49                 return;
50         tty->link->packet = 0;
51         set_bit(TTY_OTHER_CLOSED, &tty->link->flags);
52         wake_up_interruptible(&tty->link->read_wait);
53         wake_up_interruptible(&tty->link->write_wait);
54         if (tty->driver->subtype == PTY_TYPE_MASTER) {
55                 set_bit(TTY_OTHER_CLOSED, &tty->flags);
56 #ifdef CONFIG_UNIX98_PTYS
57                 if (tty->driver == ptm_driver)
58                         devpts_pty_kill(tty->link);
59 #endif
60                 tty_unlock();
61                 tty_vhangup(tty->link);
62                 tty_lock();
63         }
64 }
65
66 /*
67  * The unthrottle routine is called by the line discipline to signal
68  * that it can receive more characters.  For PTY's, the TTY_THROTTLED
69  * flag is always set, to force the line discipline to always call the
70  * unthrottle routine when there are fewer than TTY_THRESHOLD_UNTHROTTLE
71  * characters in the queue.  This is necessary since each time this
72  * happens, we need to wake up any sleeping processes that could be
73  * (1) trying to send data to the pty, or (2) waiting in wait_until_sent()
74  * for the pty buffer to be drained.
75  */
76 static void pty_unthrottle(struct tty_struct *tty)
77 {
78         tty_wakeup(tty->link);
79         set_bit(TTY_THROTTLED, &tty->flags);
80 }
81
82 /**
83  *      pty_space       -       report space left for writing
84  *      @to: tty we are writing into
85  *
86  *      The tty buffers allow 64K but we sneak a peak and clip at 8K this
87  *      allows a lot of overspill room for echo and other fun messes to
88  *      be handled properly
89  */
90
91 static int pty_space(struct tty_struct *to)
92 {
93         int n = 8192 - to->buf.memory_used;
94         if (n < 0)
95                 return 0;
96         return n;
97 }
98
99 /**
100  *      pty_write               -       write to a pty
101  *      @tty: the tty we write from
102  *      @buf: kernel buffer of data
103  *      @count: bytes to write
104  *
105  *      Our "hardware" write method. Data is coming from the ldisc which
106  *      may be in a non sleeping state. We simply throw this at the other
107  *      end of the link as if we were an IRQ handler receiving stuff for
108  *      the other side of the pty/tty pair.
109  */
110
111 static int pty_write(struct tty_struct *tty, const unsigned char *buf, int c)
112 {
113         struct tty_struct *to = tty->link;
114
115         if (tty->stopped)
116                 return 0;
117
118         if (c > 0) {
119                 /* Stuff the data into the input queue of the other end */
120                 c = tty_insert_flip_string(to, buf, c);
121                 /* And shovel */
122                 if (c) {
123                         tty_flip_buffer_push(to);
124                         tty_wakeup(tty);
125                 }
126         }
127         return c;
128 }
129
130 /**
131  *      pty_write_room  -       write space
132  *      @tty: tty we are writing from
133  *
134  *      Report how many bytes the ldisc can send into the queue for
135  *      the other device.
136  */
137
138 static int pty_write_room(struct tty_struct *tty)
139 {
140         if (tty->stopped)
141                 return 0;
142         return pty_space(tty->link);
143 }
144
145 /**
146  *      pty_chars_in_buffer     -       characters currently in our tx queue
147  *      @tty: our tty
148  *
149  *      Report how much we have in the transmit queue. As everything is
150  *      instantly at the other end this is easy to implement.
151  */
152
153 static int pty_chars_in_buffer(struct tty_struct *tty)
154 {
155         return 0;
156 }
157
158 /* Set the lock flag on a pty */
159 static int pty_set_lock(struct tty_struct *tty, int __user *arg)
160 {
161         int val;
162         if (get_user(val, arg))
163                 return -EFAULT;
164         if (val)
165                 set_bit(TTY_PTY_LOCK, &tty->flags);
166         else
167                 clear_bit(TTY_PTY_LOCK, &tty->flags);
168         return 0;
169 }
170
171 /* Send a signal to the slave */
172 static int pty_signal(struct tty_struct *tty, int sig)
173 {
174         unsigned long flags;
175         struct pid *pgrp;
176
177         if (tty->link) {
178                 spin_lock_irqsave(&tty->link->ctrl_lock, flags);
179                 pgrp = get_pid(tty->link->pgrp);
180                 spin_unlock_irqrestore(&tty->link->ctrl_lock, flags);
181
182                 kill_pgrp(pgrp, sig, 1);
183                 put_pid(pgrp);
184         }
185         return 0;
186 }
187
188 static void pty_flush_buffer(struct tty_struct *tty)
189 {
190         struct tty_struct *to = tty->link;
191         unsigned long flags;
192
193         if (!to)
194                 return;
195         /* tty_buffer_flush(to); FIXME */
196         if (to->packet) {
197                 spin_lock_irqsave(&tty->ctrl_lock, flags);
198                 tty->ctrl_status |= TIOCPKT_FLUSHWRITE;
199                 wake_up_interruptible(&to->read_wait);
200                 spin_unlock_irqrestore(&tty->ctrl_lock, flags);
201         }
202 }
203
204 static int pty_open(struct tty_struct *tty, struct file *filp)
205 {
206         int     retval = -ENODEV;
207
208         if (!tty || !tty->link)
209                 goto out;
210
211         retval = -EIO;
212         if (test_bit(TTY_OTHER_CLOSED, &tty->flags))
213                 goto out;
214         if (test_bit(TTY_PTY_LOCK, &tty->link->flags))
215                 goto out;
216         if (tty->link->count != 1)
217                 goto out;
218
219         clear_bit(TTY_OTHER_CLOSED, &tty->link->flags);
220         set_bit(TTY_THROTTLED, &tty->flags);
221         retval = 0;
222 out:
223         return retval;
224 }
225
226 static void pty_set_termios(struct tty_struct *tty,
227                                         struct ktermios *old_termios)
228 {
229         tty->termios->c_cflag &= ~(CSIZE | PARENB);
230         tty->termios->c_cflag |= (CS8 | CREAD);
231 }
232
233 /**
234  *      pty_do_resize           -       resize event
235  *      @tty: tty being resized
236  *      @ws: window size being set.
237  *
238  *      Update the termios variables and send the necessary signals to
239  *      peform a terminal resize correctly
240  */
241
242 int pty_resize(struct tty_struct *tty,  struct winsize *ws)
243 {
244         struct pid *pgrp, *rpgrp;
245         unsigned long flags;
246         struct tty_struct *pty = tty->link;
247
248         /* For a PTY we need to lock the tty side */
249         mutex_lock(&tty->termios_mutex);
250         if (!memcmp(ws, &tty->winsize, sizeof(*ws)))
251                 goto done;
252
253         /* Get the PID values and reference them so we can
254            avoid holding the tty ctrl lock while sending signals.
255            We need to lock these individually however. */
256
257         spin_lock_irqsave(&tty->ctrl_lock, flags);
258         pgrp = get_pid(tty->pgrp);
259         spin_unlock_irqrestore(&tty->ctrl_lock, flags);
260
261         spin_lock_irqsave(&pty->ctrl_lock, flags);
262         rpgrp = get_pid(pty->pgrp);
263         spin_unlock_irqrestore(&pty->ctrl_lock, flags);
264
265         if (pgrp)
266                 kill_pgrp(pgrp, SIGWINCH, 1);
267         if (rpgrp != pgrp && rpgrp)
268                 kill_pgrp(rpgrp, SIGWINCH, 1);
269
270         put_pid(pgrp);
271         put_pid(rpgrp);
272
273         tty->winsize = *ws;
274         pty->winsize = *ws;     /* Never used so will go away soon */
275 done:
276         mutex_unlock(&tty->termios_mutex);
277         return 0;
278 }
279
280 /* Traditional BSD devices */
281 #ifdef CONFIG_LEGACY_PTYS
282
283 static int pty_install(struct tty_driver *driver, struct tty_struct *tty)
284 {
285         struct tty_struct *o_tty;
286         int idx = tty->index;
287         int retval;
288
289         o_tty = alloc_tty_struct();
290         if (!o_tty)
291                 return -ENOMEM;
292         if (!try_module_get(driver->other->owner)) {
293                 /* This cannot in fact currently happen */
294                 retval = -ENOMEM;
295                 goto err_free_tty;
296         }
297         initialize_tty_struct(o_tty, driver->other, idx);
298
299         /* We always use new tty termios data so we can do this
300            the easy way .. */
301         retval = tty_init_termios(tty);
302         if (retval)
303                 goto err_deinit_tty;
304
305         retval = tty_init_termios(o_tty);
306         if (retval)
307                 goto err_free_termios;
308
309         /*
310          * Everything allocated ... set up the o_tty structure.
311          */
312         driver->other->ttys[idx] = o_tty;
313         tty_driver_kref_get(driver->other);
314         if (driver->subtype == PTY_TYPE_MASTER)
315                 o_tty->count++;
316         /* Establish the links in both directions */
317         tty->link   = o_tty;
318         o_tty->link = tty;
319
320         tty_driver_kref_get(driver);
321         tty->count++;
322         driver->ttys[idx] = tty;
323         return 0;
324 err_free_termios:
325         tty_free_termios(tty);
326 err_deinit_tty:
327         deinitialize_tty_struct(o_tty);
328         module_put(o_tty->driver->owner);
329 err_free_tty:
330         free_tty_struct(o_tty);
331         return retval;
332 }
333
334 static int pty_bsd_ioctl(struct tty_struct *tty,
335                          unsigned int cmd, unsigned long arg)
336 {
337         switch (cmd) {
338         case TIOCSPTLCK: /* Set PT Lock (disallow slave open) */
339                 return pty_set_lock(tty, (int __user *) arg);
340         case TIOCSIG:    /* Send signal to other side of pty */
341                 return pty_signal(tty, (int) arg);
342         }
343         return -ENOIOCTLCMD;
344 }
345
346 static int legacy_count = CONFIG_LEGACY_PTY_COUNT;
347 module_param(legacy_count, int, 0);
348
349 /*
350  * The master side of a pty can do TIOCSPTLCK and thus
351  * has pty_bsd_ioctl.
352  */
353 static const struct tty_operations master_pty_ops_bsd = {
354         .install = pty_install,
355         .open = pty_open,
356         .close = pty_close,
357         .write = pty_write,
358         .write_room = pty_write_room,
359         .flush_buffer = pty_flush_buffer,
360         .chars_in_buffer = pty_chars_in_buffer,
361         .unthrottle = pty_unthrottle,
362         .set_termios = pty_set_termios,
363         .ioctl = pty_bsd_ioctl,
364         .resize = pty_resize
365 };
366
367 static const struct tty_operations slave_pty_ops_bsd = {
368         .install = pty_install,
369         .open = pty_open,
370         .close = pty_close,
371         .write = pty_write,
372         .write_room = pty_write_room,
373         .flush_buffer = pty_flush_buffer,
374         .chars_in_buffer = pty_chars_in_buffer,
375         .unthrottle = pty_unthrottle,
376         .set_termios = pty_set_termios,
377         .resize = pty_resize
378 };
379
380 static void __init legacy_pty_init(void)
381 {
382         struct tty_driver *pty_driver, *pty_slave_driver;
383
384         if (legacy_count <= 0)
385                 return;
386
387         pty_driver = alloc_tty_driver(legacy_count);
388         if (!pty_driver)
389                 panic("Couldn't allocate pty driver");
390
391         pty_slave_driver = alloc_tty_driver(legacy_count);
392         if (!pty_slave_driver)
393                 panic("Couldn't allocate pty slave driver");
394
395         pty_driver->driver_name = "pty_master";
396         pty_driver->name = "pty";
397         pty_driver->major = PTY_MASTER_MAJOR;
398         pty_driver->minor_start = 0;
399         pty_driver->type = TTY_DRIVER_TYPE_PTY;
400         pty_driver->subtype = PTY_TYPE_MASTER;
401         pty_driver->init_termios = tty_std_termios;
402         pty_driver->init_termios.c_iflag = 0;
403         pty_driver->init_termios.c_oflag = 0;
404         pty_driver->init_termios.c_cflag = B38400 | CS8 | CREAD;
405         pty_driver->init_termios.c_lflag = 0;
406         pty_driver->init_termios.c_ispeed = 38400;
407         pty_driver->init_termios.c_ospeed = 38400;
408         pty_driver->flags = TTY_DRIVER_RESET_TERMIOS | TTY_DRIVER_REAL_RAW;
409         pty_driver->other = pty_slave_driver;
410         tty_set_operations(pty_driver, &master_pty_ops_bsd);
411
412         pty_slave_driver->driver_name = "pty_slave";
413         pty_slave_driver->name = "ttyp";
414         pty_slave_driver->major = PTY_SLAVE_MAJOR;
415         pty_slave_driver->minor_start = 0;
416         pty_slave_driver->type = TTY_DRIVER_TYPE_PTY;
417         pty_slave_driver->subtype = PTY_TYPE_SLAVE;
418         pty_slave_driver->init_termios = tty_std_termios;
419         pty_slave_driver->init_termios.c_cflag = B38400 | CS8 | CREAD;
420         pty_slave_driver->init_termios.c_ispeed = 38400;
421         pty_slave_driver->init_termios.c_ospeed = 38400;
422         pty_slave_driver->flags = TTY_DRIVER_RESET_TERMIOS |
423                                         TTY_DRIVER_REAL_RAW;
424         pty_slave_driver->other = pty_driver;
425         tty_set_operations(pty_slave_driver, &slave_pty_ops_bsd);
426
427         if (tty_register_driver(pty_driver))
428                 panic("Couldn't register pty driver");
429         if (tty_register_driver(pty_slave_driver))
430                 panic("Couldn't register pty slave driver");
431 }
432 #else
433 static inline void legacy_pty_init(void) { }
434 #endif
435
436 /* Unix98 devices */
437 #ifdef CONFIG_UNIX98_PTYS
438
439 static struct cdev ptmx_cdev;
440
441 static int pty_unix98_ioctl(struct tty_struct *tty,
442                             unsigned int cmd, unsigned long arg)
443 {
444         switch (cmd) {
445         case TIOCSPTLCK: /* Set PT Lock (disallow slave open) */
446                 return pty_set_lock(tty, (int __user *)arg);
447         case TIOCGPTN: /* Get PT Number */
448                 return put_user(tty->index, (unsigned int __user *)arg);
449         case TIOCSIG:    /* Send signal to other side of pty */
450                 return pty_signal(tty, (int) arg);
451         }
452
453         return -ENOIOCTLCMD;
454 }
455
456 /**
457  *      ptm_unix98_lookup       -       find a pty master
458  *      @driver: ptm driver
459  *      @idx: tty index
460  *
461  *      Look up a pty master device. Called under the tty_mutex for now.
462  *      This provides our locking.
463  */
464
465 static struct tty_struct *ptm_unix98_lookup(struct tty_driver *driver,
466                 struct inode *ptm_inode, int idx)
467 {
468         /* Master must be open via /dev/ptmx */
469         return ERR_PTR(-EIO);
470 }
471
472 /**
473  *      pts_unix98_lookup       -       find a pty slave
474  *      @driver: pts driver
475  *      @idx: tty index
476  *
477  *      Look up a pty master device. Called under the tty_mutex for now.
478  *      This provides our locking.
479  */
480
481 static struct tty_struct *pts_unix98_lookup(struct tty_driver *driver,
482                 struct inode *pts_inode, int idx)
483 {
484         struct tty_struct *tty = devpts_get_tty(pts_inode, idx);
485         /* Master must be open before slave */
486         if (!tty)
487                 return ERR_PTR(-EIO);
488         return tty;
489 }
490
491 static void pty_unix98_shutdown(struct tty_struct *tty)
492 {
493         tty_driver_remove_tty(tty->driver, tty);
494         /* We have our own method as we don't use the tty index */
495         kfree(tty->termios);
496 }
497
498 /* We have no need to install and remove our tty objects as devpts does all
499    the work for us */
500
501 static int pty_unix98_install(struct tty_driver *driver, struct tty_struct *tty)
502 {
503         struct tty_struct *o_tty;
504         int idx = tty->index;
505
506         o_tty = alloc_tty_struct();
507         if (!o_tty)
508                 return -ENOMEM;
509         if (!try_module_get(driver->other->owner)) {
510                 /* This cannot in fact currently happen */
511                 goto err_free_tty;
512         }
513         initialize_tty_struct(o_tty, driver->other, idx);
514
515         tty->termios = kzalloc(sizeof(struct ktermios[2]), GFP_KERNEL);
516         if (tty->termios == NULL)
517                 goto err_free_mem;
518         *tty->termios = driver->init_termios;
519         tty->termios_locked = tty->termios + 1;
520
521         o_tty->termios = kzalloc(sizeof(struct ktermios[2]), GFP_KERNEL);
522         if (o_tty->termios == NULL)
523                 goto err_free_mem;
524         *o_tty->termios = driver->other->init_termios;
525         o_tty->termios_locked = o_tty->termios + 1;
526
527         tty_driver_kref_get(driver->other);
528         if (driver->subtype == PTY_TYPE_MASTER)
529                 o_tty->count++;
530         /* Establish the links in both directions */
531         tty->link   = o_tty;
532         o_tty->link = tty;
533         /*
534          * All structures have been allocated, so now we install them.
535          * Failures after this point use release_tty to clean up, so
536          * there's no need to null out the local pointers.
537          */
538         tty_driver_kref_get(driver);
539         tty->count++;
540         return 0;
541 err_free_mem:
542         deinitialize_tty_struct(o_tty);
543         kfree(o_tty->termios);
544         kfree(tty->termios);
545         module_put(o_tty->driver->owner);
546 err_free_tty:
547         free_tty_struct(o_tty);
548         return -ENOMEM;
549 }
550
551 static void ptm_unix98_remove(struct tty_driver *driver, struct tty_struct *tty)
552 {
553 }
554
555 static void pts_unix98_remove(struct tty_driver *driver, struct tty_struct *tty)
556 {
557 }
558
559 static const struct tty_operations ptm_unix98_ops = {
560         .lookup = ptm_unix98_lookup,
561         .install = pty_unix98_install,
562         .remove = ptm_unix98_remove,
563         .open = pty_open,
564         .close = pty_close,
565         .write = pty_write,
566         .write_room = pty_write_room,
567         .flush_buffer = pty_flush_buffer,
568         .chars_in_buffer = pty_chars_in_buffer,
569         .unthrottle = pty_unthrottle,
570         .set_termios = pty_set_termios,
571         .ioctl = pty_unix98_ioctl,
572         .shutdown = pty_unix98_shutdown,
573         .resize = pty_resize
574 };
575
576 static const struct tty_operations pty_unix98_ops = {
577         .lookup = pts_unix98_lookup,
578         .install = pty_unix98_install,
579         .remove = pts_unix98_remove,
580         .open = pty_open,
581         .close = pty_close,
582         .write = pty_write,
583         .write_room = pty_write_room,
584         .flush_buffer = pty_flush_buffer,
585         .chars_in_buffer = pty_chars_in_buffer,
586         .unthrottle = pty_unthrottle,
587         .set_termios = pty_set_termios,
588         .shutdown = pty_unix98_shutdown
589 };
590
591 /**
592  *      ptmx_open               -       open a unix 98 pty master
593  *      @inode: inode of device file
594  *      @filp: file pointer to tty
595  *
596  *      Allocate a unix98 pty master device from the ptmx driver.
597  *
598  *      Locking: tty_mutex protects the init_dev work. tty->count should
599  *              protect the rest.
600  *              allocated_ptys_lock handles the list of free pty numbers
601  */
602
603 static int ptmx_open(struct inode *inode, struct file *filp)
604 {
605         struct tty_struct *tty;
606         int retval;
607         int index;
608
609         nonseekable_open(inode, filp);
610
611         retval = tty_alloc_file(filp);
612         if (retval)
613                 return retval;
614
615         /* find a device that is not in use. */
616         tty_lock();
617         index = devpts_new_index(inode);
618         tty_unlock();
619         if (index < 0) {
620                 retval = index;
621                 goto err_file;
622         }
623
624         mutex_lock(&tty_mutex);
625         tty_lock();
626         tty = tty_init_dev(ptm_driver, index);
627         mutex_unlock(&tty_mutex);
628
629         if (IS_ERR(tty)) {
630                 retval = PTR_ERR(tty);
631                 goto out;
632         }
633
634         set_bit(TTY_PTY_LOCK, &tty->flags); /* LOCK THE SLAVE */
635
636         tty_add_file(tty, filp);
637
638         retval = devpts_pty_new(inode, tty->link);
639         if (retval)
640                 goto err_release;
641
642         retval = ptm_driver->ops->open(tty, filp);
643         if (retval)
644                 goto err_release;
645
646         tty_unlock();
647         return 0;
648 err_release:
649         tty_unlock();
650         tty_release(inode, filp);
651         return retval;
652 out:
653         devpts_kill_index(inode, index);
654         tty_unlock();
655 err_file:
656         tty_free_file(filp);
657         return retval;
658 }
659
660 static struct file_operations ptmx_fops;
661
662 static void __init unix98_pty_init(void)
663 {
664         ptm_driver = alloc_tty_driver(NR_UNIX98_PTY_MAX);
665         if (!ptm_driver)
666                 panic("Couldn't allocate Unix98 ptm driver");
667         pts_driver = alloc_tty_driver(NR_UNIX98_PTY_MAX);
668         if (!pts_driver)
669                 panic("Couldn't allocate Unix98 pts driver");
670
671         ptm_driver->driver_name = "pty_master";
672         ptm_driver->name = "ptm";
673         ptm_driver->major = UNIX98_PTY_MASTER_MAJOR;
674         ptm_driver->minor_start = 0;
675         ptm_driver->type = TTY_DRIVER_TYPE_PTY;
676         ptm_driver->subtype = PTY_TYPE_MASTER;
677         ptm_driver->init_termios = tty_std_termios;
678         ptm_driver->init_termios.c_iflag = 0;
679         ptm_driver->init_termios.c_oflag = 0;
680         ptm_driver->init_termios.c_cflag = B38400 | CS8 | CREAD;
681         ptm_driver->init_termios.c_lflag = 0;
682         ptm_driver->init_termios.c_ispeed = 38400;
683         ptm_driver->init_termios.c_ospeed = 38400;
684         ptm_driver->flags = TTY_DRIVER_RESET_TERMIOS | TTY_DRIVER_REAL_RAW |
685                 TTY_DRIVER_DYNAMIC_DEV | TTY_DRIVER_DEVPTS_MEM;
686         ptm_driver->other = pts_driver;
687         tty_set_operations(ptm_driver, &ptm_unix98_ops);
688
689         pts_driver->driver_name = "pty_slave";
690         pts_driver->name = "pts";
691         pts_driver->major = UNIX98_PTY_SLAVE_MAJOR;
692         pts_driver->minor_start = 0;
693         pts_driver->type = TTY_DRIVER_TYPE_PTY;
694         pts_driver->subtype = PTY_TYPE_SLAVE;
695         pts_driver->init_termios = tty_std_termios;
696         pts_driver->init_termios.c_cflag = B38400 | CS8 | CREAD;
697         pts_driver->init_termios.c_ispeed = 38400;
698         pts_driver->init_termios.c_ospeed = 38400;
699         pts_driver->flags = TTY_DRIVER_RESET_TERMIOS | TTY_DRIVER_REAL_RAW |
700                 TTY_DRIVER_DYNAMIC_DEV | TTY_DRIVER_DEVPTS_MEM;
701         pts_driver->other = ptm_driver;
702         tty_set_operations(pts_driver, &pty_unix98_ops);
703
704         if (tty_register_driver(ptm_driver))
705                 panic("Couldn't register Unix98 ptm driver");
706         if (tty_register_driver(pts_driver))
707                 panic("Couldn't register Unix98 pts driver");
708
709         /* Now create the /dev/ptmx special device */
710         tty_default_fops(&ptmx_fops);
711         ptmx_fops.open = ptmx_open;
712
713         cdev_init(&ptmx_cdev, &ptmx_fops);
714         if (cdev_add(&ptmx_cdev, MKDEV(TTYAUX_MAJOR, 2), 1) ||
715             register_chrdev_region(MKDEV(TTYAUX_MAJOR, 2), 1, "/dev/ptmx") < 0)
716                 panic("Couldn't register /dev/ptmx driver\n");
717         device_create(tty_class, NULL, MKDEV(TTYAUX_MAJOR, 2), NULL, "ptmx");
718 }
719
720 #else
721 static inline void unix98_pty_init(void) { }
722 #endif
723
724 static int __init pty_init(void)
725 {
726         legacy_pty_init();
727         unix98_pty_init();
728         return 0;
729 }
730 module_init(pty_init);