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10#include <linux/module.h>
11#include <linux/errno.h>
12#include <linux/interrupt.h>
13#include <linux/tty.h>
14#include <linux/tty_flip.h>
15#include <linux/fcntl.h>
16#include <linux/sched/signal.h>
17#include <linux/string.h>
18#include <linux/major.h>
19#include <linux/mm.h>
20#include <linux/init.h>
21#include <linux/device.h>
22#include <linux/uaccess.h>
23#include <linux/bitops.h>
24#include <linux/devpts_fs.h>
25#include <linux/slab.h>
26#include <linux/mutex.h>
27#include <linux/poll.h>
28#include <linux/mount.h>
29#include <linux/file.h>
30#include <linux/ioctl.h>
31#include <linux/compat.h>
32#include "tty.h"
33
34#undef TTY_DEBUG_HANGUP
35#ifdef TTY_DEBUG_HANGUP
36# define tty_debug_hangup(tty, f, args...) tty_debug(tty, f, ##args)
37#else
38# define tty_debug_hangup(tty, f, args...) do {} while (0)
39#endif
40
41#ifdef CONFIG_UNIX98_PTYS
42static struct tty_driver *ptm_driver;
43static struct tty_driver *pts_driver;
44static DEFINE_MUTEX(devpts_mutex);
45#endif
46
47static void pty_close(struct tty_struct *tty, struct file *filp)
48{
49 if (tty->driver->subtype == PTY_TYPE_MASTER)
50 WARN_ON(tty->count > 1);
51 else {
52 if (tty_io_error(tty))
53 return;
54 if (tty->count > 2)
55 return;
56 }
57 set_bit(TTY_IO_ERROR, &tty->flags);
58 wake_up_interruptible(&tty->read_wait);
59 wake_up_interruptible(&tty->write_wait);
60 spin_lock_irq(&tty->ctrl.lock);
61 tty->ctrl.packet = false;
62 spin_unlock_irq(&tty->ctrl.lock);
63
64 if (!tty->link)
65 return;
66 set_bit(TTY_OTHER_CLOSED, &tty->link->flags);
67 wake_up_interruptible(&tty->link->read_wait);
68 wake_up_interruptible(&tty->link->write_wait);
69 if (tty->driver->subtype == PTY_TYPE_MASTER) {
70 set_bit(TTY_OTHER_CLOSED, &tty->flags);
71#ifdef CONFIG_UNIX98_PTYS
72 if (tty->driver == ptm_driver) {
73 mutex_lock(&devpts_mutex);
74 if (tty->link->driver_data)
75 devpts_pty_kill(tty->link->driver_data);
76 mutex_unlock(&devpts_mutex);
77 }
78#endif
79 tty_vhangup(tty->link);
80 }
81}
82
83
84
85
86
87
88
89
90
91
92
93static void pty_unthrottle(struct tty_struct *tty)
94{
95 tty_wakeup(tty->link);
96 set_bit(TTY_THROTTLED, &tty->flags);
97}
98
99
100
101
102
103
104
105
106
107
108
109
110
111static int pty_write(struct tty_struct *tty, const unsigned char *buf, int c)
112{
113 struct tty_struct *to = tty->link;
114 unsigned long flags;
115
116 if (tty->flow.stopped)
117 return 0;
118
119 if (c > 0) {
120 spin_lock_irqsave(&to->port->lock, flags);
121
122 c = tty_insert_flip_string(to->port, buf, c);
123 spin_unlock_irqrestore(&to->port->lock, flags);
124
125 if (c)
126 tty_flip_buffer_push(to->port);
127 }
128 return c;
129}
130
131
132
133
134
135
136
137
138
139static unsigned int pty_write_room(struct tty_struct *tty)
140{
141 if (tty->flow.stopped)
142 return 0;
143 return tty_buffer_space_avail(tty->link->port);
144}
145
146
147static int pty_set_lock(struct tty_struct *tty, int __user *arg)
148{
149 int val;
150
151 if (get_user(val, arg))
152 return -EFAULT;
153 if (val)
154 set_bit(TTY_PTY_LOCK, &tty->flags);
155 else
156 clear_bit(TTY_PTY_LOCK, &tty->flags);
157 return 0;
158}
159
160static int pty_get_lock(struct tty_struct *tty, int __user *arg)
161{
162 int locked = test_bit(TTY_PTY_LOCK, &tty->flags);
163
164 return put_user(locked, arg);
165}
166
167
168static int pty_set_pktmode(struct tty_struct *tty, int __user *arg)
169{
170 int pktmode;
171
172 if (get_user(pktmode, arg))
173 return -EFAULT;
174
175 spin_lock_irq(&tty->ctrl.lock);
176 if (pktmode) {
177 if (!tty->ctrl.packet) {
178 tty->link->ctrl.pktstatus = 0;
179 smp_mb();
180 tty->ctrl.packet = true;
181 }
182 } else
183 tty->ctrl.packet = false;
184 spin_unlock_irq(&tty->ctrl.lock);
185
186 return 0;
187}
188
189
190static int pty_get_pktmode(struct tty_struct *tty, int __user *arg)
191{
192 int pktmode = tty->ctrl.packet;
193
194 return put_user(pktmode, arg);
195}
196
197
198static int pty_signal(struct tty_struct *tty, int sig)
199{
200 struct pid *pgrp;
201
202 if (sig != SIGINT && sig != SIGQUIT && sig != SIGTSTP)
203 return -EINVAL;
204
205 if (tty->link) {
206 pgrp = tty_get_pgrp(tty->link);
207 if (pgrp)
208 kill_pgrp(pgrp, sig, 1);
209 put_pid(pgrp);
210 }
211 return 0;
212}
213
214static void pty_flush_buffer(struct tty_struct *tty)
215{
216 struct tty_struct *to = tty->link;
217
218 if (!to)
219 return;
220
221 tty_buffer_flush(to, NULL);
222 if (to->ctrl.packet) {
223 spin_lock_irq(&tty->ctrl.lock);
224 tty->ctrl.pktstatus |= TIOCPKT_FLUSHWRITE;
225 wake_up_interruptible(&to->read_wait);
226 spin_unlock_irq(&tty->ctrl.lock);
227 }
228}
229
230static int pty_open(struct tty_struct *tty, struct file *filp)
231{
232 if (!tty || !tty->link)
233 return -ENODEV;
234
235 if (test_bit(TTY_OTHER_CLOSED, &tty->flags))
236 goto out;
237 if (test_bit(TTY_PTY_LOCK, &tty->link->flags))
238 goto out;
239 if (tty->driver->subtype == PTY_TYPE_SLAVE && tty->link->count != 1)
240 goto out;
241
242 clear_bit(TTY_IO_ERROR, &tty->flags);
243 clear_bit(TTY_OTHER_CLOSED, &tty->link->flags);
244 set_bit(TTY_THROTTLED, &tty->flags);
245 return 0;
246
247out:
248 set_bit(TTY_IO_ERROR, &tty->flags);
249 return -EIO;
250}
251
252static void pty_set_termios(struct tty_struct *tty,
253 struct ktermios *old_termios)
254{
255
256 if (tty->link && tty->link->ctrl.packet) {
257 int extproc = (old_termios->c_lflag & EXTPROC) | L_EXTPROC(tty);
258 int old_flow = ((old_termios->c_iflag & IXON) &&
259 (old_termios->c_cc[VSTOP] == '\023') &&
260 (old_termios->c_cc[VSTART] == '\021'));
261 int new_flow = (I_IXON(tty) &&
262 STOP_CHAR(tty) == '\023' &&
263 START_CHAR(tty) == '\021');
264 if ((old_flow != new_flow) || extproc) {
265 spin_lock_irq(&tty->ctrl.lock);
266 if (old_flow != new_flow) {
267 tty->ctrl.pktstatus &= ~(TIOCPKT_DOSTOP | TIOCPKT_NOSTOP);
268 if (new_flow)
269 tty->ctrl.pktstatus |= TIOCPKT_DOSTOP;
270 else
271 tty->ctrl.pktstatus |= TIOCPKT_NOSTOP;
272 }
273 if (extproc)
274 tty->ctrl.pktstatus |= TIOCPKT_IOCTL;
275 spin_unlock_irq(&tty->ctrl.lock);
276 wake_up_interruptible(&tty->link->read_wait);
277 }
278 }
279
280 tty->termios.c_cflag &= ~(CSIZE | PARENB);
281 tty->termios.c_cflag |= (CS8 | CREAD);
282}
283
284
285
286
287
288
289
290
291
292
293static int pty_resize(struct tty_struct *tty, struct winsize *ws)
294{
295 struct pid *pgrp, *rpgrp;
296 struct tty_struct *pty = tty->link;
297
298
299 mutex_lock(&tty->winsize_mutex);
300 if (!memcmp(ws, &tty->winsize, sizeof(*ws)))
301 goto done;
302
303
304 pgrp = tty_get_pgrp(tty);
305 rpgrp = tty_get_pgrp(pty);
306
307 if (pgrp)
308 kill_pgrp(pgrp, SIGWINCH, 1);
309 if (rpgrp != pgrp && rpgrp)
310 kill_pgrp(rpgrp, SIGWINCH, 1);
311
312 put_pid(pgrp);
313 put_pid(rpgrp);
314
315 tty->winsize = *ws;
316 pty->winsize = *ws;
317done:
318 mutex_unlock(&tty->winsize_mutex);
319 return 0;
320}
321
322
323
324
325
326
327
328
329
330
331
332static void pty_start(struct tty_struct *tty)
333{
334 unsigned long flags;
335
336 if (tty->link && tty->link->ctrl.packet) {
337 spin_lock_irqsave(&tty->ctrl.lock, flags);
338 tty->ctrl.pktstatus &= ~TIOCPKT_STOP;
339 tty->ctrl.pktstatus |= TIOCPKT_START;
340 spin_unlock_irqrestore(&tty->ctrl.lock, flags);
341 wake_up_interruptible_poll(&tty->link->read_wait, EPOLLIN);
342 }
343}
344
345static void pty_stop(struct tty_struct *tty)
346{
347 unsigned long flags;
348
349 if (tty->link && tty->link->ctrl.packet) {
350 spin_lock_irqsave(&tty->ctrl.lock, flags);
351 tty->ctrl.pktstatus &= ~TIOCPKT_START;
352 tty->ctrl.pktstatus |= TIOCPKT_STOP;
353 spin_unlock_irqrestore(&tty->ctrl.lock, flags);
354 wake_up_interruptible_poll(&tty->link->read_wait, EPOLLIN);
355 }
356}
357
358
359
360
361
362
363
364
365
366
367
368
369static int pty_common_install(struct tty_driver *driver, struct tty_struct *tty,
370 bool legacy)
371{
372 struct tty_struct *o_tty;
373 struct tty_port *ports[2];
374 int idx = tty->index;
375 int retval = -ENOMEM;
376
377
378 if (driver->subtype != PTY_TYPE_MASTER)
379 return -EIO;
380
381 ports[0] = kmalloc(sizeof **ports, GFP_KERNEL);
382 ports[1] = kmalloc(sizeof **ports, GFP_KERNEL);
383 if (!ports[0] || !ports[1])
384 goto err;
385 if (!try_module_get(driver->other->owner)) {
386
387 goto err;
388 }
389 o_tty = alloc_tty_struct(driver->other, idx);
390 if (!o_tty)
391 goto err_put_module;
392
393 tty_set_lock_subclass(o_tty);
394 lockdep_set_subclass(&o_tty->termios_rwsem, TTY_LOCK_SLAVE);
395
396 if (legacy) {
397
398
399 tty_init_termios(tty);
400 tty_init_termios(o_tty);
401
402 driver->other->ttys[idx] = o_tty;
403 driver->ttys[idx] = tty;
404 } else {
405 memset(&tty->termios_locked, 0, sizeof(tty->termios_locked));
406 tty->termios = driver->init_termios;
407 memset(&o_tty->termios_locked, 0, sizeof(tty->termios_locked));
408 o_tty->termios = driver->other->init_termios;
409 }
410
411
412
413
414 tty_driver_kref_get(driver->other);
415
416 tty->link = o_tty;
417 o_tty->link = tty;
418 tty_port_init(ports[0]);
419 tty_port_init(ports[1]);
420 tty_buffer_set_limit(ports[0], 8192);
421 tty_buffer_set_limit(ports[1], 8192);
422 o_tty->port = ports[0];
423 tty->port = ports[1];
424 o_tty->port->itty = o_tty;
425
426 tty_buffer_set_lock_subclass(o_tty->port);
427
428 tty_driver_kref_get(driver);
429 tty->count++;
430 o_tty->count++;
431 return 0;
432
433err_put_module:
434 module_put(driver->other->owner);
435err:
436 kfree(ports[0]);
437 kfree(ports[1]);
438 return retval;
439}
440
441static void pty_cleanup(struct tty_struct *tty)
442{
443 tty_port_put(tty->port);
444}
445
446
447#ifdef CONFIG_LEGACY_PTYS
448
449static int pty_install(struct tty_driver *driver, struct tty_struct *tty)
450{
451 return pty_common_install(driver, tty, true);
452}
453
454static void pty_remove(struct tty_driver *driver, struct tty_struct *tty)
455{
456 struct tty_struct *pair = tty->link;
457
458 driver->ttys[tty->index] = NULL;
459 if (pair)
460 pair->driver->ttys[pair->index] = NULL;
461}
462
463static int pty_bsd_ioctl(struct tty_struct *tty,
464 unsigned int cmd, unsigned long arg)
465{
466 switch (cmd) {
467 case TIOCSPTLCK:
468 return pty_set_lock(tty, (int __user *) arg);
469 case TIOCGPTLCK:
470 return pty_get_lock(tty, (int __user *)arg);
471 case TIOCPKT:
472 return pty_set_pktmode(tty, (int __user *)arg);
473 case TIOCGPKT:
474 return pty_get_pktmode(tty, (int __user *)arg);
475 case TIOCSIG:
476 return pty_signal(tty, (int) arg);
477 case TIOCGPTN:
478 return -EINVAL;
479 }
480 return -ENOIOCTLCMD;
481}
482
483#ifdef CONFIG_COMPAT
484static long pty_bsd_compat_ioctl(struct tty_struct *tty,
485 unsigned int cmd, unsigned long arg)
486{
487
488
489
490
491 return pty_bsd_ioctl(tty, cmd, (unsigned long)compat_ptr(arg));
492}
493#else
494#define pty_bsd_compat_ioctl NULL
495#endif
496
497static int legacy_count = CONFIG_LEGACY_PTY_COUNT;
498
499
500
501
502module_param(legacy_count, int, 0);
503
504
505
506
507
508static const struct tty_operations master_pty_ops_bsd = {
509 .install = pty_install,
510 .open = pty_open,
511 .close = pty_close,
512 .write = pty_write,
513 .write_room = pty_write_room,
514 .flush_buffer = pty_flush_buffer,
515 .unthrottle = pty_unthrottle,
516 .ioctl = pty_bsd_ioctl,
517 .compat_ioctl = pty_bsd_compat_ioctl,
518 .cleanup = pty_cleanup,
519 .resize = pty_resize,
520 .remove = pty_remove
521};
522
523static const struct tty_operations slave_pty_ops_bsd = {
524 .install = pty_install,
525 .open = pty_open,
526 .close = pty_close,
527 .write = pty_write,
528 .write_room = pty_write_room,
529 .flush_buffer = pty_flush_buffer,
530 .unthrottle = pty_unthrottle,
531 .set_termios = pty_set_termios,
532 .cleanup = pty_cleanup,
533 .resize = pty_resize,
534 .start = pty_start,
535 .stop = pty_stop,
536 .remove = pty_remove
537};
538
539static void __init legacy_pty_init(void)
540{
541 struct tty_driver *pty_driver, *pty_slave_driver;
542
543 if (legacy_count <= 0)
544 return;
545
546 pty_driver = tty_alloc_driver(legacy_count,
547 TTY_DRIVER_RESET_TERMIOS |
548 TTY_DRIVER_REAL_RAW |
549 TTY_DRIVER_DYNAMIC_ALLOC);
550 if (IS_ERR(pty_driver))
551 panic("Couldn't allocate pty driver");
552
553 pty_slave_driver = tty_alloc_driver(legacy_count,
554 TTY_DRIVER_RESET_TERMIOS |
555 TTY_DRIVER_REAL_RAW |
556 TTY_DRIVER_DYNAMIC_ALLOC);
557 if (IS_ERR(pty_slave_driver))
558 panic("Couldn't allocate pty slave driver");
559
560 pty_driver->driver_name = "pty_master";
561 pty_driver->name = "pty";
562 pty_driver->major = PTY_MASTER_MAJOR;
563 pty_driver->minor_start = 0;
564 pty_driver->type = TTY_DRIVER_TYPE_PTY;
565 pty_driver->subtype = PTY_TYPE_MASTER;
566 pty_driver->init_termios = tty_std_termios;
567 pty_driver->init_termios.c_iflag = 0;
568 pty_driver->init_termios.c_oflag = 0;
569 pty_driver->init_termios.c_cflag = B38400 | CS8 | CREAD;
570 pty_driver->init_termios.c_lflag = 0;
571 pty_driver->init_termios.c_ispeed = 38400;
572 pty_driver->init_termios.c_ospeed = 38400;
573 pty_driver->other = pty_slave_driver;
574 tty_set_operations(pty_driver, &master_pty_ops_bsd);
575
576 pty_slave_driver->driver_name = "pty_slave";
577 pty_slave_driver->name = "ttyp";
578 pty_slave_driver->major = PTY_SLAVE_MAJOR;
579 pty_slave_driver->minor_start = 0;
580 pty_slave_driver->type = TTY_DRIVER_TYPE_PTY;
581 pty_slave_driver->subtype = PTY_TYPE_SLAVE;
582 pty_slave_driver->init_termios = tty_std_termios;
583 pty_slave_driver->init_termios.c_cflag = B38400 | CS8 | CREAD;
584 pty_slave_driver->init_termios.c_ispeed = 38400;
585 pty_slave_driver->init_termios.c_ospeed = 38400;
586 pty_slave_driver->other = pty_driver;
587 tty_set_operations(pty_slave_driver, &slave_pty_ops_bsd);
588
589 if (tty_register_driver(pty_driver))
590 panic("Couldn't register pty driver");
591 if (tty_register_driver(pty_slave_driver))
592 panic("Couldn't register pty slave driver");
593}
594#else
595static inline void legacy_pty_init(void) { }
596#endif
597
598
599#ifdef CONFIG_UNIX98_PTYS
600static struct cdev ptmx_cdev;
601
602
603
604
605
606
607
608
609
610
611
612int ptm_open_peer(struct file *master, struct tty_struct *tty, int flags)
613{
614 int fd;
615 struct file *filp;
616 int retval = -EINVAL;
617 struct path path;
618
619 if (tty->driver != ptm_driver)
620 return -EIO;
621
622 fd = get_unused_fd_flags(flags);
623 if (fd < 0) {
624 retval = fd;
625 goto err;
626 }
627
628
629 path.mnt = devpts_mntget(master, tty->driver_data);
630 if (IS_ERR(path.mnt)) {
631 retval = PTR_ERR(path.mnt);
632 goto err_put;
633 }
634 path.dentry = tty->link->driver_data;
635
636 filp = dentry_open(&path, flags, current_cred());
637 mntput(path.mnt);
638 if (IS_ERR(filp)) {
639 retval = PTR_ERR(filp);
640 goto err_put;
641 }
642
643 fd_install(fd, filp);
644 return fd;
645
646err_put:
647 put_unused_fd(fd);
648err:
649 return retval;
650}
651
652static int pty_unix98_ioctl(struct tty_struct *tty,
653 unsigned int cmd, unsigned long arg)
654{
655 switch (cmd) {
656 case TIOCSPTLCK:
657 return pty_set_lock(tty, (int __user *)arg);
658 case TIOCGPTLCK:
659 return pty_get_lock(tty, (int __user *)arg);
660 case TIOCPKT:
661 return pty_set_pktmode(tty, (int __user *)arg);
662 case TIOCGPKT:
663 return pty_get_pktmode(tty, (int __user *)arg);
664 case TIOCGPTN:
665 return put_user(tty->index, (unsigned int __user *)arg);
666 case TIOCSIG:
667 return pty_signal(tty, (int) arg);
668 }
669
670 return -ENOIOCTLCMD;
671}
672
673#ifdef CONFIG_COMPAT
674static long pty_unix98_compat_ioctl(struct tty_struct *tty,
675 unsigned int cmd, unsigned long arg)
676{
677
678
679
680
681 return pty_unix98_ioctl(tty, cmd,
682 cmd == TIOCSIG ? arg : (unsigned long)compat_ptr(arg));
683}
684#else
685#define pty_unix98_compat_ioctl NULL
686#endif
687
688
689
690
691
692
693
694
695
696
697
698static struct tty_struct *ptm_unix98_lookup(struct tty_driver *driver,
699 struct file *file, int idx)
700{
701
702 return ERR_PTR(-EIO);
703}
704
705
706
707
708
709
710
711
712
713
714
715static struct tty_struct *pts_unix98_lookup(struct tty_driver *driver,
716 struct file *file, int idx)
717{
718 struct tty_struct *tty;
719
720 mutex_lock(&devpts_mutex);
721 tty = devpts_get_priv(file->f_path.dentry);
722 mutex_unlock(&devpts_mutex);
723
724 if (!tty)
725 return ERR_PTR(-EIO);
726 return tty;
727}
728
729static int pty_unix98_install(struct tty_driver *driver, struct tty_struct *tty)
730{
731 return pty_common_install(driver, tty, false);
732}
733
734
735static void pty_unix98_remove(struct tty_driver *driver, struct tty_struct *tty)
736{
737 struct pts_fs_info *fsi;
738
739 if (tty->driver->subtype == PTY_TYPE_MASTER)
740 fsi = tty->driver_data;
741 else
742 fsi = tty->link->driver_data;
743
744 if (fsi) {
745 devpts_kill_index(fsi, tty->index);
746 devpts_release(fsi);
747 }
748}
749
750static void pty_show_fdinfo(struct tty_struct *tty, struct seq_file *m)
751{
752 seq_printf(m, "tty-index:\t%d\n", tty->index);
753}
754
755static const struct tty_operations ptm_unix98_ops = {
756 .lookup = ptm_unix98_lookup,
757 .install = pty_unix98_install,
758 .remove = pty_unix98_remove,
759 .open = pty_open,
760 .close = pty_close,
761 .write = pty_write,
762 .write_room = pty_write_room,
763 .flush_buffer = pty_flush_buffer,
764 .unthrottle = pty_unthrottle,
765 .ioctl = pty_unix98_ioctl,
766 .compat_ioctl = pty_unix98_compat_ioctl,
767 .resize = pty_resize,
768 .cleanup = pty_cleanup,
769 .show_fdinfo = pty_show_fdinfo,
770};
771
772static const struct tty_operations pty_unix98_ops = {
773 .lookup = pts_unix98_lookup,
774 .install = pty_unix98_install,
775 .remove = pty_unix98_remove,
776 .open = pty_open,
777 .close = pty_close,
778 .write = pty_write,
779 .write_room = pty_write_room,
780 .flush_buffer = pty_flush_buffer,
781 .unthrottle = pty_unthrottle,
782 .set_termios = pty_set_termios,
783 .start = pty_start,
784 .stop = pty_stop,
785 .cleanup = pty_cleanup,
786};
787
788
789
790
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792
793
794
795
796
797
798
799
800static int ptmx_open(struct inode *inode, struct file *filp)
801{
802 struct pts_fs_info *fsi;
803 struct tty_struct *tty;
804 struct dentry *dentry;
805 int retval;
806 int index;
807
808 nonseekable_open(inode, filp);
809
810
811 filp->f_mode |= FMODE_NONOTIFY;
812
813 retval = tty_alloc_file(filp);
814 if (retval)
815 return retval;
816
817 fsi = devpts_acquire(filp);
818 if (IS_ERR(fsi)) {
819 retval = PTR_ERR(fsi);
820 goto out_free_file;
821 }
822
823
824 mutex_lock(&devpts_mutex);
825 index = devpts_new_index(fsi);
826 mutex_unlock(&devpts_mutex);
827
828 retval = index;
829 if (index < 0)
830 goto out_put_fsi;
831
832
833 mutex_lock(&tty_mutex);
834 tty = tty_init_dev(ptm_driver, index);
835
836
837 mutex_unlock(&tty_mutex);
838
839 retval = PTR_ERR(tty);
840 if (IS_ERR(tty))
841 goto out;
842
843
844
845
846
847 set_bit(TTY_PTY_LOCK, &tty->flags);
848 tty->driver_data = fsi;
849
850 tty_add_file(tty, filp);
851
852 dentry = devpts_pty_new(fsi, index, tty->link);
853 if (IS_ERR(dentry)) {
854 retval = PTR_ERR(dentry);
855 goto err_release;
856 }
857 tty->link->driver_data = dentry;
858
859 retval = ptm_driver->ops->open(tty, filp);
860 if (retval)
861 goto err_release;
862
863 tty_debug_hangup(tty, "opening (count=%d)\n", tty->count);
864
865 tty_unlock(tty);
866 return 0;
867err_release:
868 tty_unlock(tty);
869
870 tty_release(inode, filp);
871 return retval;
872out:
873 devpts_kill_index(fsi, index);
874out_put_fsi:
875 devpts_release(fsi);
876out_free_file:
877 tty_free_file(filp);
878 return retval;
879}
880
881static struct file_operations ptmx_fops __ro_after_init;
882
883static void __init unix98_pty_init(void)
884{
885 ptm_driver = tty_alloc_driver(NR_UNIX98_PTY_MAX,
886 TTY_DRIVER_RESET_TERMIOS |
887 TTY_DRIVER_REAL_RAW |
888 TTY_DRIVER_DYNAMIC_DEV |
889 TTY_DRIVER_DEVPTS_MEM |
890 TTY_DRIVER_DYNAMIC_ALLOC);
891 if (IS_ERR(ptm_driver))
892 panic("Couldn't allocate Unix98 ptm driver");
893 pts_driver = tty_alloc_driver(NR_UNIX98_PTY_MAX,
894 TTY_DRIVER_RESET_TERMIOS |
895 TTY_DRIVER_REAL_RAW |
896 TTY_DRIVER_DYNAMIC_DEV |
897 TTY_DRIVER_DEVPTS_MEM |
898 TTY_DRIVER_DYNAMIC_ALLOC);
899 if (IS_ERR(pts_driver))
900 panic("Couldn't allocate Unix98 pts driver");
901
902 ptm_driver->driver_name = "pty_master";
903 ptm_driver->name = "ptm";
904 ptm_driver->major = UNIX98_PTY_MASTER_MAJOR;
905 ptm_driver->minor_start = 0;
906 ptm_driver->type = TTY_DRIVER_TYPE_PTY;
907 ptm_driver->subtype = PTY_TYPE_MASTER;
908 ptm_driver->init_termios = tty_std_termios;
909 ptm_driver->init_termios.c_iflag = 0;
910 ptm_driver->init_termios.c_oflag = 0;
911 ptm_driver->init_termios.c_cflag = B38400 | CS8 | CREAD;
912 ptm_driver->init_termios.c_lflag = 0;
913 ptm_driver->init_termios.c_ispeed = 38400;
914 ptm_driver->init_termios.c_ospeed = 38400;
915 ptm_driver->other = pts_driver;
916 tty_set_operations(ptm_driver, &ptm_unix98_ops);
917
918 pts_driver->driver_name = "pty_slave";
919 pts_driver->name = "pts";
920 pts_driver->major = UNIX98_PTY_SLAVE_MAJOR;
921 pts_driver->minor_start = 0;
922 pts_driver->type = TTY_DRIVER_TYPE_PTY;
923 pts_driver->subtype = PTY_TYPE_SLAVE;
924 pts_driver->init_termios = tty_std_termios;
925 pts_driver->init_termios.c_cflag = B38400 | CS8 | CREAD;
926 pts_driver->init_termios.c_ispeed = 38400;
927 pts_driver->init_termios.c_ospeed = 38400;
928 pts_driver->other = ptm_driver;
929 tty_set_operations(pts_driver, &pty_unix98_ops);
930
931 if (tty_register_driver(ptm_driver))
932 panic("Couldn't register Unix98 ptm driver");
933 if (tty_register_driver(pts_driver))
934 panic("Couldn't register Unix98 pts driver");
935
936
937 tty_default_fops(&ptmx_fops);
938 ptmx_fops.open = ptmx_open;
939
940 cdev_init(&ptmx_cdev, &ptmx_fops);
941 if (cdev_add(&ptmx_cdev, MKDEV(TTYAUX_MAJOR, 2), 1) ||
942 register_chrdev_region(MKDEV(TTYAUX_MAJOR, 2), 1, "/dev/ptmx") < 0)
943 panic("Couldn't register /dev/ptmx driver");
944 device_create(tty_class, NULL, MKDEV(TTYAUX_MAJOR, 2), NULL, "ptmx");
945}
946
947#else
948static inline void unix98_pty_init(void) { }
949#endif
950
951static int __init pty_init(void)
952{
953 legacy_pty_init();
954 unix98_pty_init();
955 return 0;
956}
957device_initcall(pty_init);
958