Merge branch 'x86-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git...
[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                 .procname       = "max",
435                 .maxlen         = sizeof(int),
436                 .mode           = 0644,
437                 .data           = &pty_limit,
438                 .proc_handler   = proc_dointvec_minmax,
439                 .extra1         = &pty_limit_min,
440                 .extra2         = &pty_limit_max,
441         }, {
442                 .procname       = "nr",
443                 .maxlen         = sizeof(int),
444                 .mode           = 0444,
445                 .data           = &pty_count,
446                 .proc_handler   = proc_dointvec,
447         }, 
448         {}
449 };
450
451 static struct ctl_table pty_kern_table[] = {
452         {
453                 .procname       = "pty",
454                 .mode           = 0555,
455                 .child          = pty_table,
456         },
457         {}
458 };
459
460 static struct ctl_table pty_root_table[] = {
461         {
462                 .procname       = "kernel",
463                 .mode           = 0555,
464                 .child          = pty_kern_table,
465         },
466         {}
467 };
468
469
470 static int pty_unix98_ioctl(struct tty_struct *tty, struct file *file,
471                             unsigned int cmd, unsigned long arg)
472 {
473         switch (cmd) {
474         case TIOCSPTLCK: /* Set PT Lock (disallow slave open) */
475                 return pty_set_lock(tty, (int __user *)arg);
476         case TIOCGPTN: /* Get PT Number */
477                 return put_user(tty->index, (unsigned int __user *)arg);
478         }
479
480         return -ENOIOCTLCMD;
481 }
482
483 /**
484  *      ptm_unix98_lookup       -       find a pty master
485  *      @driver: ptm driver
486  *      @idx: tty index
487  *
488  *      Look up a pty master device. Called under the tty_mutex for now.
489  *      This provides our locking.
490  */
491
492 static struct tty_struct *ptm_unix98_lookup(struct tty_driver *driver,
493                 struct inode *ptm_inode, int idx)
494 {
495         struct tty_struct *tty = devpts_get_tty(ptm_inode, idx);
496         if (tty)
497                 tty = tty->link;
498         return tty;
499 }
500
501 /**
502  *      pts_unix98_lookup       -       find a pty slave
503  *      @driver: pts driver
504  *      @idx: tty index
505  *
506  *      Look up a pty master device. Called under the tty_mutex for now.
507  *      This provides our locking.
508  */
509
510 static struct tty_struct *pts_unix98_lookup(struct tty_driver *driver,
511                 struct inode *pts_inode, int idx)
512 {
513         struct tty_struct *tty = devpts_get_tty(pts_inode, idx);
514         /* Master must be open before slave */
515         if (!tty)
516                 return ERR_PTR(-EIO);
517         return tty;
518 }
519
520 static void pty_unix98_shutdown(struct tty_struct *tty)
521 {
522         /* We have our own method as we don't use the tty index */
523         kfree(tty->termios);
524 }
525
526 /* We have no need to install and remove our tty objects as devpts does all
527    the work for us */
528
529 static int pty_unix98_install(struct tty_driver *driver, struct tty_struct *tty)
530 {
531         struct tty_struct *o_tty;
532         int idx = tty->index;
533
534         o_tty = alloc_tty_struct();
535         if (!o_tty)
536                 return -ENOMEM;
537         if (!try_module_get(driver->other->owner)) {
538                 /* This cannot in fact currently happen */
539                 free_tty_struct(o_tty);
540                 return -ENOMEM;
541         }
542         initialize_tty_struct(o_tty, driver->other, idx);
543
544         tty->termios = kzalloc(sizeof(struct ktermios[2]), GFP_KERNEL);
545         if (tty->termios == NULL)
546                 goto free_mem_out;
547         *tty->termios = driver->init_termios;
548         tty->termios_locked = tty->termios + 1;
549
550         o_tty->termios = kzalloc(sizeof(struct ktermios[2]), GFP_KERNEL);
551         if (o_tty->termios == NULL)
552                 goto free_mem_out;
553         *o_tty->termios = driver->other->init_termios;
554         o_tty->termios_locked = o_tty->termios + 1;
555
556         tty_driver_kref_get(driver->other);
557         if (driver->subtype == PTY_TYPE_MASTER)
558                 o_tty->count++;
559         /* Establish the links in both directions */
560         tty->link   = o_tty;
561         o_tty->link = tty;
562         /*
563          * All structures have been allocated, so now we install them.
564          * Failures after this point use release_tty to clean up, so
565          * there's no need to null out the local pointers.
566          */
567         tty_driver_kref_get(driver);
568         tty->count++;
569         pty_count++;
570         return 0;
571 free_mem_out:
572         kfree(o_tty->termios);
573         module_put(o_tty->driver->owner);
574         free_tty_struct(o_tty);
575         kfree(tty->termios);
576         return -ENOMEM;
577 }
578
579 static void pty_unix98_remove(struct tty_driver *driver, struct tty_struct *tty)
580 {
581         pty_count--;
582 }
583
584 static const struct tty_operations ptm_unix98_ops = {
585         .lookup = ptm_unix98_lookup,
586         .install = pty_unix98_install,
587         .remove = pty_unix98_remove,
588         .open = pty_open,
589         .close = pty_close,
590         .write = pty_write,
591         .write_room = pty_write_room,
592         .flush_buffer = pty_flush_buffer,
593         .chars_in_buffer = pty_chars_in_buffer,
594         .unthrottle = pty_unthrottle,
595         .set_termios = pty_set_termios,
596         .ioctl = pty_unix98_ioctl,
597         .shutdown = pty_unix98_shutdown,
598         .resize = pty_resize
599 };
600
601 static const struct tty_operations pty_unix98_ops = {
602         .lookup = pts_unix98_lookup,
603         .install = pty_unix98_install,
604         .remove = pty_unix98_remove,
605         .open = pty_open,
606         .close = pty_close,
607         .write = pty_write,
608         .write_room = pty_write_room,
609         .flush_buffer = pty_flush_buffer,
610         .chars_in_buffer = pty_chars_in_buffer,
611         .unthrottle = pty_unthrottle,
612         .set_termios = pty_set_termios,
613         .shutdown = pty_unix98_shutdown
614 };
615
616 /**
617  *      ptmx_open               -       open a unix 98 pty master
618  *      @inode: inode of device file
619  *      @filp: file pointer to tty
620  *
621  *      Allocate a unix98 pty master device from the ptmx driver.
622  *
623  *      Locking: tty_mutex protects the init_dev work. tty->count should
624  *              protect the rest.
625  *              allocated_ptys_lock handles the list of free pty numbers
626  */
627
628 static int __ptmx_open(struct inode *inode, struct file *filp)
629 {
630         struct tty_struct *tty;
631         int retval;
632         int index;
633
634         nonseekable_open(inode, filp);
635
636         /* find a device that is not in use. */
637         index = devpts_new_index(inode);
638         if (index < 0)
639                 return index;
640
641         mutex_lock(&tty_mutex);
642         tty = tty_init_dev(ptm_driver, index, 1);
643         mutex_unlock(&tty_mutex);
644
645         if (IS_ERR(tty)) {
646                 retval = PTR_ERR(tty);
647                 goto out;
648         }
649
650         set_bit(TTY_PTY_LOCK, &tty->flags); /* LOCK THE SLAVE */
651         filp->private_data = tty;
652         file_move(filp, &tty->tty_files);
653
654         retval = devpts_pty_new(inode, tty->link);
655         if (retval)
656                 goto out1;
657
658         retval = ptm_driver->ops->open(tty, filp);
659         if (!retval)
660                 return 0;
661 out1:
662         tty_release(inode, filp);
663         return retval;
664 out:
665         devpts_kill_index(inode, index);
666         return retval;
667 }
668
669 static int ptmx_open(struct inode *inode, struct file *filp)
670 {
671         int ret;
672
673         lock_kernel();
674         ret = __ptmx_open(inode, filp);
675         unlock_kernel();
676         return ret;
677 }
678
679 static struct file_operations ptmx_fops;
680
681 static void __init unix98_pty_init(void)
682 {
683         ptm_driver = alloc_tty_driver(NR_UNIX98_PTY_MAX);
684         if (!ptm_driver)
685                 panic("Couldn't allocate Unix98 ptm driver");
686         pts_driver = alloc_tty_driver(NR_UNIX98_PTY_MAX);
687         if (!pts_driver)
688                 panic("Couldn't allocate Unix98 pts driver");
689
690         ptm_driver->owner = THIS_MODULE;
691         ptm_driver->driver_name = "pty_master";
692         ptm_driver->name = "ptm";
693         ptm_driver->major = UNIX98_PTY_MASTER_MAJOR;
694         ptm_driver->minor_start = 0;
695         ptm_driver->type = TTY_DRIVER_TYPE_PTY;
696         ptm_driver->subtype = PTY_TYPE_MASTER;
697         ptm_driver->init_termios = tty_std_termios;
698         ptm_driver->init_termios.c_iflag = 0;
699         ptm_driver->init_termios.c_oflag = 0;
700         ptm_driver->init_termios.c_cflag = B38400 | CS8 | CREAD;
701         ptm_driver->init_termios.c_lflag = 0;
702         ptm_driver->init_termios.c_ispeed = 38400;
703         ptm_driver->init_termios.c_ospeed = 38400;
704         ptm_driver->flags = TTY_DRIVER_RESET_TERMIOS | TTY_DRIVER_REAL_RAW |
705                 TTY_DRIVER_DYNAMIC_DEV | TTY_DRIVER_DEVPTS_MEM;
706         ptm_driver->other = pts_driver;
707         tty_set_operations(ptm_driver, &ptm_unix98_ops);
708
709         pts_driver->owner = THIS_MODULE;
710         pts_driver->driver_name = "pty_slave";
711         pts_driver->name = "pts";
712         pts_driver->major = UNIX98_PTY_SLAVE_MAJOR;
713         pts_driver->minor_start = 0;
714         pts_driver->type = TTY_DRIVER_TYPE_PTY;
715         pts_driver->subtype = PTY_TYPE_SLAVE;
716         pts_driver->init_termios = tty_std_termios;
717         pts_driver->init_termios.c_cflag = B38400 | CS8 | CREAD;
718         pts_driver->init_termios.c_ispeed = 38400;
719         pts_driver->init_termios.c_ospeed = 38400;
720         pts_driver->flags = TTY_DRIVER_RESET_TERMIOS | TTY_DRIVER_REAL_RAW |
721                 TTY_DRIVER_DYNAMIC_DEV | TTY_DRIVER_DEVPTS_MEM;
722         pts_driver->other = ptm_driver;
723         tty_set_operations(pts_driver, &pty_unix98_ops);
724
725         if (tty_register_driver(ptm_driver))
726                 panic("Couldn't register Unix98 ptm driver");
727         if (tty_register_driver(pts_driver))
728                 panic("Couldn't register Unix98 pts driver");
729
730         register_sysctl_table(pty_root_table);
731
732         /* Now create the /dev/ptmx special device */
733         tty_default_fops(&ptmx_fops);
734         ptmx_fops.open = ptmx_open;
735
736         cdev_init(&ptmx_cdev, &ptmx_fops);
737         if (cdev_add(&ptmx_cdev, MKDEV(TTYAUX_MAJOR, 2), 1) ||
738             register_chrdev_region(MKDEV(TTYAUX_MAJOR, 2), 1, "/dev/ptmx") < 0)
739                 panic("Couldn't register /dev/ptmx driver\n");
740         device_create(tty_class, NULL, MKDEV(TTYAUX_MAJOR, 2), NULL, "ptmx");
741 }
742
743 #else
744 static inline void unix98_pty_init(void) { }
745 #endif
746
747 static int __init pty_init(void)
748 {
749         legacy_pty_init();
750         unix98_pty_init();
751         return 0;
752 }
753 module_init(pty_init);