Merge branch 'master' of git://git.kernel.org/pub/scm/linux/kernel/git/kaber/nf-next-2.6
[linux-2.6.git] / drivers / char / pty.c
1 /*
2  *  linux/drivers/char/pty.c
3  *
4  *  Copyright (C) 1991, 1992  Linus Torvalds
5  *
6  *  Added support for a Unix98-style ptmx device.
7  *    -- C. Scott Ananian <cananian@alumni.princeton.edu>, 14-Jan-1998
8  *
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.
12  */
13
14 #include <linux/module.h>
15
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
33 #include <asm/system.h>
34
35 #ifdef CONFIG_UNIX98_PTYS
36 static struct tty_driver *ptm_driver;
37 static struct tty_driver *pts_driver;
38 #endif
39
40 static void pty_close(struct tty_struct *tty, struct file *filp)
41 {
42         BUG_ON(!tty);
43         if (tty->driver->subtype == PTY_TYPE_MASTER)
44                 WARN_ON(tty->count > 1);
45         else {
46                 if (tty->count > 2)
47                         return;
48         }
49         wake_up_interruptible(&tty->read_wait);
50         wake_up_interruptible(&tty->write_wait);
51         tty->packet = 0;
52         if (!tty->link)
53                 return;
54         tty->link->packet = 0;
55         set_bit(TTY_OTHER_CLOSED, &tty->link->flags);
56         wake_up_interruptible(&tty->link->read_wait);
57         wake_up_interruptible(&tty->link->write_wait);
58         if (tty->driver->subtype == PTY_TYPE_MASTER) {
59                 set_bit(TTY_OTHER_CLOSED, &tty->flags);
60 #ifdef CONFIG_UNIX98_PTYS
61                 if (tty->driver == ptm_driver)
62                         devpts_pty_kill(tty->link);
63 #endif
64                 tty_vhangup(tty->link);
65         }
66 }
67
68 /*
69  * The unthrottle routine is called by the line discipline to signal
70  * that it can receive more characters.  For PTY's, the TTY_THROTTLED
71  * flag is always set, to force the line discipline to always call the
72  * unthrottle routine when there are fewer than TTY_THRESHOLD_UNTHROTTLE
73  * characters in the queue.  This is necessary since each time this
74  * happens, we need to wake up any sleeping processes that could be
75  * (1) trying to send data to the pty, or (2) waiting in wait_until_sent()
76  * for the pty buffer to be drained.
77  */
78 static void pty_unthrottle(struct tty_struct *tty)
79 {
80         tty_wakeup(tty->link);
81         set_bit(TTY_THROTTLED, &tty->flags);
82 }
83
84 /**
85  *      pty_space       -       report space left for writing
86  *      @to: tty we are writing into
87  *
88  *      The tty buffers allow 64K but we sneak a peak and clip at 8K this
89  *      allows a lot of overspill room for echo and other fun messes to
90  *      be handled properly
91  */
92
93 static int pty_space(struct tty_struct *to)
94 {
95         int n = 8192 - to->buf.memory_used;
96         if (n < 0)
97                 return 0;
98         return n;
99 }
100
101 /**
102  *      pty_write               -       write to a pty
103  *      @tty: the tty we write from
104  *      @buf: kernel buffer of data
105  *      @count: bytes to write
106  *
107  *      Our "hardware" write method. Data is coming from the ldisc which
108  *      may be in a non sleeping state. We simply throw this at the other
109  *      end of the link as if we were an IRQ handler receiving stuff for
110  *      the other side of the pty/tty pair.
111  */
112
113 static int pty_write(struct tty_struct *tty, const unsigned char *buf, int c)
114 {
115         struct tty_struct *to = tty->link;
116
117         if (tty->stopped)
118                 return 0;
119
120         if (c > 0) {
121                 /* Stuff the data into the input queue of the other end */
122                 c = tty_insert_flip_string(to, buf, c);
123                 /* And shovel */
124                 if (c) {
125                         tty_flip_buffer_push(to);
126                         tty_wakeup(tty);
127                 }
128         }
129         return c;
130 }
131
132 /**
133  *      pty_write_room  -       write space
134  *      @tty: tty we are writing from
135  *
136  *      Report how many bytes the ldisc can send into the queue for
137  *      the other device.
138  */
139
140 static int pty_write_room(struct tty_struct *tty)
141 {
142         if (tty->stopped)
143                 return 0;
144         return pty_space(tty->link);
145 }
146
147 /**
148  *      pty_chars_in_buffer     -       characters currently in our tx queue
149  *      @tty: our tty
150  *
151  *      Report how much we have in the transmit queue. As everything is
152  *      instantly at the other end this is easy to implement.
153  */
154
155 static int pty_chars_in_buffer(struct tty_struct *tty)
156 {
157         return 0;
158 }
159
160 /* Set the lock flag on a pty */
161 static int pty_set_lock(struct tty_struct *tty, int __user *arg)
162 {
163         int val;
164         if (get_user(val, arg))
165                 return -EFAULT;
166         if (val)
167                 set_bit(TTY_PTY_LOCK, &tty->flags);
168         else
169                 clear_bit(TTY_PTY_LOCK, &tty->flags);
170         return 0;
171 }
172
173 static void pty_flush_buffer(struct tty_struct *tty)
174 {
175         struct tty_struct *to = tty->link;
176         unsigned long flags;
177
178         if (!to)
179                 return;
180         /* tty_buffer_flush(to); FIXME */
181         if (to->packet) {
182                 spin_lock_irqsave(&tty->ctrl_lock, flags);
183                 tty->ctrl_status |= TIOCPKT_FLUSHWRITE;
184                 wake_up_interruptible(&to->read_wait);
185                 spin_unlock_irqrestore(&tty->ctrl_lock, flags);
186         }
187 }
188
189 static int pty_open(struct tty_struct *tty, struct file *filp)
190 {
191         int     retval = -ENODEV;
192
193         if (!tty || !tty->link)
194                 goto out;
195
196         retval = -EIO;
197         if (test_bit(TTY_OTHER_CLOSED, &tty->flags))
198                 goto out;
199         if (test_bit(TTY_PTY_LOCK, &tty->link->flags))
200                 goto out;
201         if (tty->link->count != 1)
202                 goto out;
203
204         clear_bit(TTY_OTHER_CLOSED, &tty->link->flags);
205         set_bit(TTY_THROTTLED, &tty->flags);
206         retval = 0;
207 out:
208         return retval;
209 }
210
211 static void pty_set_termios(struct tty_struct *tty,
212                                         struct ktermios *old_termios)
213 {
214         tty->termios->c_cflag &= ~(CSIZE | PARENB);
215         tty->termios->c_cflag |= (CS8 | CREAD);
216 }
217
218 /**
219  *      pty_do_resize           -       resize event
220  *      @tty: tty being resized
221  *      @ws: window size being set.
222  *
223  *      Update the termios variables and send the neccessary signals to
224  *      peform a terminal resize correctly
225  */
226
227 int pty_resize(struct tty_struct *tty,  struct winsize *ws)
228 {
229         struct pid *pgrp, *rpgrp;
230         unsigned long flags;
231         struct tty_struct *pty = tty->link;
232
233         /* For a PTY we need to lock the tty side */
234         mutex_lock(&tty->termios_mutex);
235         if (!memcmp(ws, &tty->winsize, sizeof(*ws)))
236                 goto done;
237
238         /* Get the PID values and reference them so we can
239            avoid holding the tty ctrl lock while sending signals.
240            We need to lock these individually however. */
241
242         spin_lock_irqsave(&tty->ctrl_lock, flags);
243         pgrp = get_pid(tty->pgrp);
244         spin_unlock_irqrestore(&tty->ctrl_lock, flags);
245
246         spin_lock_irqsave(&pty->ctrl_lock, flags);
247         rpgrp = get_pid(pty->pgrp);
248         spin_unlock_irqrestore(&pty->ctrl_lock, flags);
249
250         if (pgrp)
251                 kill_pgrp(pgrp, SIGWINCH, 1);
252         if (rpgrp != pgrp && rpgrp)
253                 kill_pgrp(rpgrp, SIGWINCH, 1);
254
255         put_pid(pgrp);
256         put_pid(rpgrp);
257
258         tty->winsize = *ws;
259         pty->winsize = *ws;     /* Never used so will go away soon */
260 done:
261         mutex_unlock(&tty->termios_mutex);
262         return 0;
263 }
264
265 /* Traditional BSD devices */
266 #ifdef CONFIG_LEGACY_PTYS
267
268 static int pty_install(struct tty_driver *driver, struct tty_struct *tty)
269 {
270         struct tty_struct *o_tty;
271         int idx = tty->index;
272         int retval;
273
274         o_tty = alloc_tty_struct();
275         if (!o_tty)
276                 return -ENOMEM;
277         if (!try_module_get(driver->other->owner)) {
278                 /* This cannot in fact currently happen */
279                 free_tty_struct(o_tty);
280                 return -ENOMEM;
281         }
282         initialize_tty_struct(o_tty, driver->other, idx);
283
284         /* We always use new tty termios data so we can do this
285            the easy way .. */
286         retval = tty_init_termios(tty);
287         if (retval)
288                 goto free_mem_out;
289
290         retval = tty_init_termios(o_tty);
291         if (retval) {
292                 tty_free_termios(tty);
293                 goto free_mem_out;
294         }
295
296         /*
297          * Everything allocated ... set up the o_tty structure.
298          */
299         driver->other->ttys[idx] = o_tty;
300         tty_driver_kref_get(driver->other);
301         if (driver->subtype == PTY_TYPE_MASTER)
302                 o_tty->count++;
303         /* Establish the links in both directions */
304         tty->link   = o_tty;
305         o_tty->link = tty;
306
307         tty_driver_kref_get(driver);
308         tty->count++;
309         driver->ttys[idx] = tty;
310         return 0;
311 free_mem_out:
312         module_put(o_tty->driver->owner);
313         free_tty_struct(o_tty);
314         return -ENOMEM;
315 }
316
317 static int pty_bsd_ioctl(struct tty_struct *tty, struct file *file,
318                          unsigned int cmd, unsigned long arg)
319 {
320         switch (cmd) {
321         case TIOCSPTLCK: /* Set PT Lock (disallow slave open) */
322                 return pty_set_lock(tty, (int __user *) arg);
323         }
324         return -ENOIOCTLCMD;
325 }
326
327 static int legacy_count = CONFIG_LEGACY_PTY_COUNT;
328 module_param(legacy_count, int, 0);
329
330 /*
331  * The master side of a pty can do TIOCSPTLCK and thus
332  * has pty_bsd_ioctl.
333  */
334 static const struct tty_operations master_pty_ops_bsd = {
335         .install = pty_install,
336         .open = pty_open,
337         .close = pty_close,
338         .write = pty_write,
339         .write_room = pty_write_room,
340         .flush_buffer = pty_flush_buffer,
341         .chars_in_buffer = pty_chars_in_buffer,
342         .unthrottle = pty_unthrottle,
343         .set_termios = pty_set_termios,
344         .ioctl = pty_bsd_ioctl,
345         .resize = pty_resize
346 };
347
348 static const struct tty_operations slave_pty_ops_bsd = {
349         .install = pty_install,
350         .open = pty_open,
351         .close = pty_close,
352         .write = pty_write,
353         .write_room = pty_write_room,
354         .flush_buffer = pty_flush_buffer,
355         .chars_in_buffer = pty_chars_in_buffer,
356         .unthrottle = pty_unthrottle,
357         .set_termios = pty_set_termios,
358         .resize = pty_resize
359 };
360
361 static void __init legacy_pty_init(void)
362 {
363         struct tty_driver *pty_driver, *pty_slave_driver;
364
365         if (legacy_count <= 0)
366                 return;
367
368         pty_driver = alloc_tty_driver(legacy_count);
369         if (!pty_driver)
370                 panic("Couldn't allocate pty driver");
371
372         pty_slave_driver = alloc_tty_driver(legacy_count);
373         if (!pty_slave_driver)
374                 panic("Couldn't allocate pty slave driver");
375
376         pty_driver->owner = THIS_MODULE;
377         pty_driver->driver_name = "pty_master";
378         pty_driver->name = "pty";
379         pty_driver->major = PTY_MASTER_MAJOR;
380         pty_driver->minor_start = 0;
381         pty_driver->type = TTY_DRIVER_TYPE_PTY;
382         pty_driver->subtype = PTY_TYPE_MASTER;
383         pty_driver->init_termios = tty_std_termios;
384         pty_driver->init_termios.c_iflag = 0;
385         pty_driver->init_termios.c_oflag = 0;
386         pty_driver->init_termios.c_cflag = B38400 | CS8 | CREAD;
387         pty_driver->init_termios.c_lflag = 0;
388         pty_driver->init_termios.c_ispeed = 38400;
389         pty_driver->init_termios.c_ospeed = 38400;
390         pty_driver->flags = TTY_DRIVER_RESET_TERMIOS | TTY_DRIVER_REAL_RAW;
391         pty_driver->other = pty_slave_driver;
392         tty_set_operations(pty_driver, &master_pty_ops_bsd);
393
394         pty_slave_driver->owner = THIS_MODULE;
395         pty_slave_driver->driver_name = "pty_slave";
396         pty_slave_driver->name = "ttyp";
397         pty_slave_driver->major = PTY_SLAVE_MAJOR;
398         pty_slave_driver->minor_start = 0;
399         pty_slave_driver->type = TTY_DRIVER_TYPE_PTY;
400         pty_slave_driver->subtype = PTY_TYPE_SLAVE;
401         pty_slave_driver->init_termios = tty_std_termios;
402         pty_slave_driver->init_termios.c_cflag = B38400 | CS8 | CREAD;
403         pty_slave_driver->init_termios.c_ispeed = 38400;
404         pty_slave_driver->init_termios.c_ospeed = 38400;
405         pty_slave_driver->flags = TTY_DRIVER_RESET_TERMIOS |
406                                         TTY_DRIVER_REAL_RAW;
407         pty_slave_driver->other = pty_driver;
408         tty_set_operations(pty_slave_driver, &slave_pty_ops_bsd);
409
410         if (tty_register_driver(pty_driver))
411                 panic("Couldn't register pty driver");
412         if (tty_register_driver(pty_slave_driver))
413                 panic("Couldn't register pty slave driver");
414 }
415 #else
416 static inline void legacy_pty_init(void) { }
417 #endif
418
419 /* Unix98 devices */
420 #ifdef CONFIG_UNIX98_PTYS
421 /*
422  * sysctl support for setting limits on the number of Unix98 ptys allocated.
423  * Otherwise one can eat up all kernel memory by opening /dev/ptmx repeatedly.
424  */
425 int pty_limit = NR_UNIX98_PTY_DEFAULT;
426 static int pty_limit_min;
427 static int pty_limit_max = NR_UNIX98_PTY_MAX;
428 static int pty_count;
429
430 static struct cdev ptmx_cdev;
431
432 static struct ctl_table pty_table[] = {
433         {
434                 .ctl_name       = PTY_MAX,
435                 .procname       = "max",
436                 .maxlen         = sizeof(int),
437                 .mode           = 0644,
438                 .data           = &pty_limit,
439                 .proc_handler   = &proc_dointvec_minmax,
440                 .strategy       = &sysctl_intvec,
441                 .extra1         = &pty_limit_min,
442                 .extra2         = &pty_limit_max,
443         }, {
444                 .ctl_name       = PTY_NR,
445                 .procname       = "nr",
446                 .maxlen         = sizeof(int),
447                 .mode           = 0444,
448                 .data           = &pty_count,
449                 .proc_handler   = &proc_dointvec,
450         }, {
451                 .ctl_name       = 0
452         }
453 };
454
455 static struct ctl_table pty_kern_table[] = {
456         {
457                 .ctl_name       = KERN_PTY,
458                 .procname       = "pty",
459                 .mode           = 0555,
460                 .child          = pty_table,
461         },
462         {}
463 };
464
465 static struct ctl_table pty_root_table[] = {
466         {
467                 .ctl_name       = CTL_KERN,
468                 .procname       = "kernel",
469                 .mode           = 0555,
470                 .child          = pty_kern_table,
471         },
472         {}
473 };
474
475
476 static int pty_unix98_ioctl(struct tty_struct *tty, struct file *file,
477                             unsigned int cmd, unsigned long arg)
478 {
479         switch (cmd) {
480         case TIOCSPTLCK: /* Set PT Lock (disallow slave open) */
481                 return pty_set_lock(tty, (int __user *)arg);
482         case TIOCGPTN: /* Get PT Number */
483                 return put_user(tty->index, (unsigned int __user *)arg);
484         }
485
486         return -ENOIOCTLCMD;
487 }
488
489 /**
490  *      ptm_unix98_lookup       -       find a pty master
491  *      @driver: ptm driver
492  *      @idx: tty index
493  *
494  *      Look up a pty master device. Called under the tty_mutex for now.
495  *      This provides our locking.
496  */
497
498 static struct tty_struct *ptm_unix98_lookup(struct tty_driver *driver,
499                 struct inode *ptm_inode, int idx)
500 {
501         struct tty_struct *tty = devpts_get_tty(ptm_inode, idx);
502         if (tty)
503                 tty = tty->link;
504         return tty;
505 }
506
507 /**
508  *      pts_unix98_lookup       -       find a pty slave
509  *      @driver: pts driver
510  *      @idx: tty index
511  *
512  *      Look up a pty master device. Called under the tty_mutex for now.
513  *      This provides our locking.
514  */
515
516 static struct tty_struct *pts_unix98_lookup(struct tty_driver *driver,
517                 struct inode *pts_inode, int idx)
518 {
519         struct tty_struct *tty = devpts_get_tty(pts_inode, idx);
520         /* Master must be open before slave */
521         if (!tty)
522                 return ERR_PTR(-EIO);
523         return tty;
524 }
525
526 static void pty_unix98_shutdown(struct tty_struct *tty)
527 {
528         /* We have our own method as we don't use the tty index */
529         kfree(tty->termios);
530 }
531
532 /* We have no need to install and remove our tty objects as devpts does all
533    the work for us */
534
535 static int pty_unix98_install(struct tty_driver *driver, struct tty_struct *tty)
536 {
537         struct tty_struct *o_tty;
538         int idx = tty->index;
539
540         o_tty = alloc_tty_struct();
541         if (!o_tty)
542                 return -ENOMEM;
543         if (!try_module_get(driver->other->owner)) {
544                 /* This cannot in fact currently happen */
545                 free_tty_struct(o_tty);
546                 return -ENOMEM;
547         }
548         initialize_tty_struct(o_tty, driver->other, idx);
549
550         tty->termios = kzalloc(sizeof(struct ktermios[2]), GFP_KERNEL);
551         if (tty->termios == NULL)
552                 goto free_mem_out;
553         *tty->termios = driver->init_termios;
554         tty->termios_locked = tty->termios + 1;
555
556         o_tty->termios = kzalloc(sizeof(struct ktermios[2]), GFP_KERNEL);
557         if (o_tty->termios == NULL)
558                 goto free_mem_out;
559         *o_tty->termios = driver->other->init_termios;
560         o_tty->termios_locked = o_tty->termios + 1;
561
562         tty_driver_kref_get(driver->other);
563         if (driver->subtype == PTY_TYPE_MASTER)
564                 o_tty->count++;
565         /* Establish the links in both directions */
566         tty->link   = o_tty;
567         o_tty->link = tty;
568         /*
569          * All structures have been allocated, so now we install them.
570          * Failures after this point use release_tty to clean up, so
571          * there's no need to null out the local pointers.
572          */
573         tty_driver_kref_get(driver);
574         tty->count++;
575         pty_count++;
576         return 0;
577 free_mem_out:
578         kfree(o_tty->termios);
579         module_put(o_tty->driver->owner);
580         free_tty_struct(o_tty);
581         kfree(tty->termios);
582         return -ENOMEM;
583 }
584
585 static void pty_unix98_remove(struct tty_driver *driver, struct tty_struct *tty)
586 {
587         pty_count--;
588 }
589
590 static const struct tty_operations ptm_unix98_ops = {
591         .lookup = ptm_unix98_lookup,
592         .install = pty_unix98_install,
593         .remove = pty_unix98_remove,
594         .open = pty_open,
595         .close = pty_close,
596         .write = pty_write,
597         .write_room = pty_write_room,
598         .flush_buffer = pty_flush_buffer,
599         .chars_in_buffer = pty_chars_in_buffer,
600         .unthrottle = pty_unthrottle,
601         .set_termios = pty_set_termios,
602         .ioctl = pty_unix98_ioctl,
603         .shutdown = pty_unix98_shutdown,
604         .resize = pty_resize
605 };
606
607 static const struct tty_operations pty_unix98_ops = {
608         .lookup = pts_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         .shutdown = pty_unix98_shutdown
620 };
621
622 /**
623  *      ptmx_open               -       open a unix 98 pty master
624  *      @inode: inode of device file
625  *      @filp: file pointer to tty
626  *
627  *      Allocate a unix98 pty master device from the ptmx driver.
628  *
629  *      Locking: tty_mutex protects the init_dev work. tty->count should
630  *              protect the rest.
631  *              allocated_ptys_lock handles the list of free pty numbers
632  */
633
634 static int __ptmx_open(struct inode *inode, struct file *filp)
635 {
636         struct tty_struct *tty;
637         int retval;
638         int index;
639
640         nonseekable_open(inode, filp);
641
642         /* find a device that is not in use. */
643         index = devpts_new_index(inode);
644         if (index < 0)
645                 return index;
646
647         mutex_lock(&tty_mutex);
648         tty = tty_init_dev(ptm_driver, index, 1);
649         mutex_unlock(&tty_mutex);
650
651         if (IS_ERR(tty)) {
652                 retval = PTR_ERR(tty);
653                 goto out;
654         }
655
656         set_bit(TTY_PTY_LOCK, &tty->flags); /* LOCK THE SLAVE */
657         filp->private_data = tty;
658         file_move(filp, &tty->tty_files);
659
660         retval = devpts_pty_new(inode, tty->link);
661         if (retval)
662                 goto out1;
663
664         retval = ptm_driver->ops->open(tty, filp);
665         if (!retval)
666                 return 0;
667 out1:
668         tty_release_dev(filp);
669         return retval;
670 out:
671         devpts_kill_index(inode, index);
672         return retval;
673 }
674
675 static int ptmx_open(struct inode *inode, struct file *filp)
676 {
677         int ret;
678
679         lock_kernel();
680         ret = __ptmx_open(inode, filp);
681         unlock_kernel();
682         return ret;
683 }
684
685 static struct file_operations ptmx_fops;
686
687 static void __init unix98_pty_init(void)
688 {
689         ptm_driver = alloc_tty_driver(NR_UNIX98_PTY_MAX);
690         if (!ptm_driver)
691                 panic("Couldn't allocate Unix98 ptm driver");
692         pts_driver = alloc_tty_driver(NR_UNIX98_PTY_MAX);
693         if (!pts_driver)
694                 panic("Couldn't allocate Unix98 pts driver");
695
696         ptm_driver->owner = THIS_MODULE;
697         ptm_driver->driver_name = "pty_master";
698         ptm_driver->name = "ptm";
699         ptm_driver->major = UNIX98_PTY_MASTER_MAJOR;
700         ptm_driver->minor_start = 0;
701         ptm_driver->type = TTY_DRIVER_TYPE_PTY;
702         ptm_driver->subtype = PTY_TYPE_MASTER;
703         ptm_driver->init_termios = tty_std_termios;
704         ptm_driver->init_termios.c_iflag = 0;
705         ptm_driver->init_termios.c_oflag = 0;
706         ptm_driver->init_termios.c_cflag = B38400 | CS8 | CREAD;
707         ptm_driver->init_termios.c_lflag = 0;
708         ptm_driver->init_termios.c_ispeed = 38400;
709         ptm_driver->init_termios.c_ospeed = 38400;
710         ptm_driver->flags = TTY_DRIVER_RESET_TERMIOS | TTY_DRIVER_REAL_RAW |
711                 TTY_DRIVER_DYNAMIC_DEV | TTY_DRIVER_DEVPTS_MEM;
712         ptm_driver->other = pts_driver;
713         tty_set_operations(ptm_driver, &ptm_unix98_ops);
714
715         pts_driver->owner = THIS_MODULE;
716         pts_driver->driver_name = "pty_slave";
717         pts_driver->name = "pts";
718         pts_driver->major = UNIX98_PTY_SLAVE_MAJOR;
719         pts_driver->minor_start = 0;
720         pts_driver->type = TTY_DRIVER_TYPE_PTY;
721         pts_driver->subtype = PTY_TYPE_SLAVE;
722         pts_driver->init_termios = tty_std_termios;
723         pts_driver->init_termios.c_cflag = B38400 | CS8 | CREAD;
724         pts_driver->init_termios.c_ispeed = 38400;
725         pts_driver->init_termios.c_ospeed = 38400;
726         pts_driver->flags = TTY_DRIVER_RESET_TERMIOS | TTY_DRIVER_REAL_RAW |
727                 TTY_DRIVER_DYNAMIC_DEV | TTY_DRIVER_DEVPTS_MEM;
728         pts_driver->other = ptm_driver;
729         tty_set_operations(pts_driver, &pty_unix98_ops);
730
731         if (tty_register_driver(ptm_driver))
732                 panic("Couldn't register Unix98 ptm driver");
733         if (tty_register_driver(pts_driver))
734                 panic("Couldn't register Unix98 pts driver");
735
736         register_sysctl_table(pty_root_table);
737
738         /* Now create the /dev/ptmx special device */
739         tty_default_fops(&ptmx_fops);
740         ptmx_fops.open = ptmx_open;
741
742         cdev_init(&ptmx_cdev, &ptmx_fops);
743         if (cdev_add(&ptmx_cdev, MKDEV(TTYAUX_MAJOR, 2), 1) ||
744             register_chrdev_region(MKDEV(TTYAUX_MAJOR, 2), 1, "/dev/ptmx") < 0)
745                 panic("Couldn't register /dev/ptmx driver\n");
746         device_create(tty_class, NULL, MKDEV(TTYAUX_MAJOR, 2), NULL, "ptmx");
747 }
748
749 #else
750 static inline void unix98_pty_init(void) { }
751 #endif
752
753 static int __init pty_init(void)
754 {
755         legacy_pty_init();
756         unix98_pty_init();
757         return 0;
758 }
759 module_init(pty_init);