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 #include <linux/slab.h> 33 34 #include <asm/system.h> 35 36 #ifdef CONFIG_UNIX98_PTYS 37 static struct tty_driver *ptm_driver; 38 static struct tty_driver *pts_driver; 39 #endif 40 41 static void pty_close(struct tty_struct *tty, struct file *filp) 42 { 43 BUG_ON(!tty); 44 if (tty->driver->subtype == PTY_TYPE_MASTER) 45 WARN_ON(tty->count > 1); 46 else { 47 if (tty->count > 2) 48 return; 49 } 50 wake_up_interruptible(&tty->read_wait); 51 wake_up_interruptible(&tty->write_wait); 52 tty->packet = 0; 53 if (!tty->link) 54 return; 55 tty->link->packet = 0; 56 set_bit(TTY_OTHER_CLOSED, &tty->link->flags); 57 wake_up_interruptible(&tty->link->read_wait); 58 wake_up_interruptible(&tty->link->write_wait); 59 if (tty->driver->subtype == PTY_TYPE_MASTER) { 60 set_bit(TTY_OTHER_CLOSED, &tty->flags); 61 #ifdef CONFIG_UNIX98_PTYS 62 if (tty->driver == ptm_driver) 63 devpts_pty_kill(tty->link); 64 #endif 65 tty_unlock(); 66 tty_vhangup(tty->link); 67 tty_lock(); 68 } 69 } 70 71 /* 72 * The unthrottle routine is called by the line discipline to signal 73 * that it can receive more characters. For PTY's, the TTY_THROTTLED 74 * flag is always set, to force the line discipline to always call the 75 * unthrottle routine when there are fewer than TTY_THRESHOLD_UNTHROTTLE 76 * characters in the queue. This is necessary since each time this 77 * happens, we need to wake up any sleeping processes that could be 78 * (1) trying to send data to the pty, or (2) waiting in wait_until_sent() 79 * for the pty buffer to be drained. 80 */ 81 static void pty_unthrottle(struct tty_struct *tty) 82 { 83 tty_wakeup(tty->link); 84 set_bit(TTY_THROTTLED, &tty->flags); 85 } 86 87 /** 88 * pty_space - report space left for writing 89 * @to: tty we are writing into 90 * 91 * The tty buffers allow 64K but we sneak a peak and clip at 8K this 92 * allows a lot of overspill room for echo and other fun messes to 93 * be handled properly 94 */ 95 96 static int pty_space(struct tty_struct *to) 97 { 98 int n = 8192 - to->buf.memory_used; 99 if (n < 0) 100 return 0; 101 return n; 102 } 103 104 /** 105 * pty_write - write to a pty 106 * @tty: the tty we write from 107 * @buf: kernel buffer of data 108 * @count: bytes to write 109 * 110 * Our "hardware" write method. Data is coming from the ldisc which 111 * may be in a non sleeping state. We simply throw this at the other 112 * end of the link as if we were an IRQ handler receiving stuff for 113 * the other side of the pty/tty pair. 114 */ 115 116 static int pty_write(struct tty_struct *tty, const unsigned char *buf, int c) 117 { 118 struct tty_struct *to = tty->link; 119 120 if (tty->stopped) 121 return 0; 122 123 if (c > 0) { 124 /* Stuff the data into the input queue of the other end */ 125 c = tty_insert_flip_string(to, buf, c); 126 /* And shovel */ 127 if (c) { 128 tty_flip_buffer_push(to); 129 tty_wakeup(tty); 130 } 131 } 132 return c; 133 } 134 135 /** 136 * pty_write_room - write space 137 * @tty: tty we are writing from 138 * 139 * Report how many bytes the ldisc can send into the queue for 140 * the other device. 141 */ 142 143 static int pty_write_room(struct tty_struct *tty) 144 { 145 if (tty->stopped) 146 return 0; 147 return pty_space(tty->link); 148 } 149 150 /** 151 * pty_chars_in_buffer - characters currently in our tx queue 152 * @tty: our tty 153 * 154 * Report how much we have in the transmit queue. As everything is 155 * instantly at the other end this is easy to implement. 156 */ 157 158 static int pty_chars_in_buffer(struct tty_struct *tty) 159 { 160 return 0; 161 } 162 163 /* Set the lock flag on a pty */ 164 static int pty_set_lock(struct tty_struct *tty, int __user *arg) 165 { 166 int val; 167 if (get_user(val, arg)) 168 return -EFAULT; 169 if (val) 170 set_bit(TTY_PTY_LOCK, &tty->flags); 171 else 172 clear_bit(TTY_PTY_LOCK, &tty->flags); 173 return 0; 174 } 175 176 /* Send a signal to the slave */ 177 static int pty_signal(struct tty_struct *tty, int sig) 178 { 179 unsigned long flags; 180 struct pid *pgrp; 181 182 if (tty->link) { 183 spin_lock_irqsave(&tty->link->ctrl_lock, flags); 184 pgrp = get_pid(tty->link->pgrp); 185 spin_unlock_irqrestore(&tty->link->ctrl_lock, flags); 186 187 kill_pgrp(pgrp, sig, 1); 188 put_pid(pgrp); 189 } 190 return 0; 191 } 192 193 static void pty_flush_buffer(struct tty_struct *tty) 194 { 195 struct tty_struct *to = tty->link; 196 unsigned long flags; 197 198 if (!to) 199 return; 200 /* tty_buffer_flush(to); FIXME */ 201 if (to->packet) { 202 spin_lock_irqsave(&tty->ctrl_lock, flags); 203 tty->ctrl_status |= TIOCPKT_FLUSHWRITE; 204 wake_up_interruptible(&to->read_wait); 205 spin_unlock_irqrestore(&tty->ctrl_lock, flags); 206 } 207 } 208 209 static int pty_open(struct tty_struct *tty, struct file *filp) 210 { 211 int retval = -ENODEV; 212 213 if (!tty || !tty->link) 214 goto out; 215 216 retval = -EIO; 217 if (test_bit(TTY_OTHER_CLOSED, &tty->flags)) 218 goto out; 219 if (test_bit(TTY_PTY_LOCK, &tty->link->flags)) 220 goto out; 221 if (tty->link->count != 1) 222 goto out; 223 224 clear_bit(TTY_OTHER_CLOSED, &tty->link->flags); 225 set_bit(TTY_THROTTLED, &tty->flags); 226 retval = 0; 227 out: 228 return retval; 229 } 230 231 static void pty_set_termios(struct tty_struct *tty, 232 struct ktermios *old_termios) 233 { 234 tty->termios->c_cflag &= ~(CSIZE | PARENB); 235 tty->termios->c_cflag |= (CS8 | CREAD); 236 } 237 238 /** 239 * pty_do_resize - resize event 240 * @tty: tty being resized 241 * @ws: window size being set. 242 * 243 * Update the termios variables and send the necessary signals to 244 * peform a terminal resize correctly 245 */ 246 247 int pty_resize(struct tty_struct *tty, struct winsize *ws) 248 { 249 struct pid *pgrp, *rpgrp; 250 unsigned long flags; 251 struct tty_struct *pty = tty->link; 252 253 /* For a PTY we need to lock the tty side */ 254 mutex_lock(&tty->termios_mutex); 255 if (!memcmp(ws, &tty->winsize, sizeof(*ws))) 256 goto done; 257 258 /* Get the PID values and reference them so we can 259 avoid holding the tty ctrl lock while sending signals. 260 We need to lock these individually however. */ 261 262 spin_lock_irqsave(&tty->ctrl_lock, flags); 263 pgrp = get_pid(tty->pgrp); 264 spin_unlock_irqrestore(&tty->ctrl_lock, flags); 265 266 spin_lock_irqsave(&pty->ctrl_lock, flags); 267 rpgrp = get_pid(pty->pgrp); 268 spin_unlock_irqrestore(&pty->ctrl_lock, flags); 269 270 if (pgrp) 271 kill_pgrp(pgrp, SIGWINCH, 1); 272 if (rpgrp != pgrp && rpgrp) 273 kill_pgrp(rpgrp, SIGWINCH, 1); 274 275 put_pid(pgrp); 276 put_pid(rpgrp); 277 278 tty->winsize = *ws; 279 pty->winsize = *ws; /* Never used so will go away soon */ 280 done: 281 mutex_unlock(&tty->termios_mutex); 282 return 0; 283 } 284 285 /* Traditional BSD devices */ 286 #ifdef CONFIG_LEGACY_PTYS 287 288 static int pty_install(struct tty_driver *driver, struct tty_struct *tty) 289 { 290 struct tty_struct *o_tty; 291 int idx = tty->index; 292 int retval; 293 294 o_tty = alloc_tty_struct(); 295 if (!o_tty) 296 return -ENOMEM; 297 if (!try_module_get(driver->other->owner)) { 298 /* This cannot in fact currently happen */ 299 free_tty_struct(o_tty); 300 return -ENOMEM; 301 } 302 initialize_tty_struct(o_tty, driver->other, idx); 303 304 /* We always use new tty termios data so we can do this 305 the easy way .. */ 306 retval = tty_init_termios(tty); 307 if (retval) 308 goto free_mem_out; 309 310 retval = tty_init_termios(o_tty); 311 if (retval) { 312 tty_free_termios(tty); 313 goto free_mem_out; 314 } 315 316 /* 317 * Everything allocated ... set up the o_tty structure. 318 */ 319 driver->other->ttys[idx] = o_tty; 320 tty_driver_kref_get(driver->other); 321 if (driver->subtype == PTY_TYPE_MASTER) 322 o_tty->count++; 323 /* Establish the links in both directions */ 324 tty->link = o_tty; 325 o_tty->link = tty; 326 327 tty_driver_kref_get(driver); 328 tty->count++; 329 driver->ttys[idx] = tty; 330 return 0; 331 free_mem_out: 332 module_put(o_tty->driver->owner); 333 free_tty_struct(o_tty); 334 return -ENOMEM; 335 } 336 337 static int pty_bsd_ioctl(struct tty_struct *tty, struct file *file, 338 unsigned int cmd, unsigned long arg) 339 { 340 switch (cmd) { 341 case TIOCSPTLCK: /* Set PT Lock (disallow slave open) */ 342 return pty_set_lock(tty, (int __user *) arg); 343 case TIOCSIG: /* Send signal to other side of pty */ 344 return pty_signal(tty, (int) arg); 345 } 346 return -ENOIOCTLCMD; 347 } 348 349 static int legacy_count = CONFIG_LEGACY_PTY_COUNT; 350 module_param(legacy_count, int, 0); 351 352 /* 353 * The master side of a pty can do TIOCSPTLCK and thus 354 * has pty_bsd_ioctl. 355 */ 356 static const struct tty_operations master_pty_ops_bsd = { 357 .install = pty_install, 358 .open = pty_open, 359 .close = pty_close, 360 .write = pty_write, 361 .write_room = pty_write_room, 362 .flush_buffer = pty_flush_buffer, 363 .chars_in_buffer = pty_chars_in_buffer, 364 .unthrottle = pty_unthrottle, 365 .set_termios = pty_set_termios, 366 .ioctl = pty_bsd_ioctl, 367 .resize = pty_resize 368 }; 369 370 static const struct tty_operations slave_pty_ops_bsd = { 371 .install = pty_install, 372 .open = pty_open, 373 .close = pty_close, 374 .write = pty_write, 375 .write_room = pty_write_room, 376 .flush_buffer = pty_flush_buffer, 377 .chars_in_buffer = pty_chars_in_buffer, 378 .unthrottle = pty_unthrottle, 379 .set_termios = pty_set_termios, 380 .resize = pty_resize 381 }; 382 383 static void __init legacy_pty_init(void) 384 { 385 struct tty_driver *pty_driver, *pty_slave_driver; 386 387 if (legacy_count <= 0) 388 return; 389 390 pty_driver = alloc_tty_driver(legacy_count); 391 if (!pty_driver) 392 panic("Couldn't allocate pty driver"); 393 394 pty_slave_driver = alloc_tty_driver(legacy_count); 395 if (!pty_slave_driver) 396 panic("Couldn't allocate pty slave driver"); 397 398 pty_driver->owner = THIS_MODULE; 399 pty_driver->driver_name = "pty_master"; 400 pty_driver->name = "pty"; 401 pty_driver->major = PTY_MASTER_MAJOR; 402 pty_driver->minor_start = 0; 403 pty_driver->type = TTY_DRIVER_TYPE_PTY; 404 pty_driver->subtype = PTY_TYPE_MASTER; 405 pty_driver->init_termios = tty_std_termios; 406 pty_driver->init_termios.c_iflag = 0; 407 pty_driver->init_termios.c_oflag = 0; 408 pty_driver->init_termios.c_cflag = B38400 | CS8 | CREAD; 409 pty_driver->init_termios.c_lflag = 0; 410 pty_driver->init_termios.c_ispeed = 38400; 411 pty_driver->init_termios.c_ospeed = 38400; 412 pty_driver->flags = TTY_DRIVER_RESET_TERMIOS | TTY_DRIVER_REAL_RAW; 413 pty_driver->other = pty_slave_driver; 414 tty_set_operations(pty_driver, &master_pty_ops_bsd); 415 416 pty_slave_driver->owner = THIS_MODULE; 417 pty_slave_driver->driver_name = "pty_slave"; 418 pty_slave_driver->name = "ttyp"; 419 pty_slave_driver->major = PTY_SLAVE_MAJOR; 420 pty_slave_driver->minor_start = 0; 421 pty_slave_driver->type = TTY_DRIVER_TYPE_PTY; 422 pty_slave_driver->subtype = PTY_TYPE_SLAVE; 423 pty_slave_driver->init_termios = tty_std_termios; 424 pty_slave_driver->init_termios.c_cflag = B38400 | CS8 | CREAD; 425 pty_slave_driver->init_termios.c_ispeed = 38400; 426 pty_slave_driver->init_termios.c_ospeed = 38400; 427 pty_slave_driver->flags = TTY_DRIVER_RESET_TERMIOS | 428 TTY_DRIVER_REAL_RAW; 429 pty_slave_driver->other = pty_driver; 430 tty_set_operations(pty_slave_driver, &slave_pty_ops_bsd); 431 432 if (tty_register_driver(pty_driver)) 433 panic("Couldn't register pty driver"); 434 if (tty_register_driver(pty_slave_driver)) 435 panic("Couldn't register pty slave driver"); 436 } 437 #else 438 static inline void legacy_pty_init(void) { } 439 #endif 440 441 /* Unix98 devices */ 442 #ifdef CONFIG_UNIX98_PTYS 443 /* 444 * sysctl support for setting limits on the number of Unix98 ptys allocated. 445 * Otherwise one can eat up all kernel memory by opening /dev/ptmx repeatedly. 446 */ 447 int pty_limit = NR_UNIX98_PTY_DEFAULT; 448 static int pty_limit_min; 449 static int pty_limit_max = NR_UNIX98_PTY_MAX; 450 static int pty_count; 451 452 static struct cdev ptmx_cdev; 453 454 static struct ctl_table pty_table[] = { 455 { 456 .procname = "max", 457 .maxlen = sizeof(int), 458 .mode = 0644, 459 .data = &pty_limit, 460 .proc_handler = proc_dointvec_minmax, 461 .extra1 = &pty_limit_min, 462 .extra2 = &pty_limit_max, 463 }, { 464 .procname = "nr", 465 .maxlen = sizeof(int), 466 .mode = 0444, 467 .data = &pty_count, 468 .proc_handler = proc_dointvec, 469 }, 470 {} 471 }; 472 473 static struct ctl_table pty_kern_table[] = { 474 { 475 .procname = "pty", 476 .mode = 0555, 477 .child = pty_table, 478 }, 479 {} 480 }; 481 482 static struct ctl_table pty_root_table[] = { 483 { 484 .procname = "kernel", 485 .mode = 0555, 486 .child = pty_kern_table, 487 }, 488 {} 489 }; 490 491 492 static int pty_unix98_ioctl(struct tty_struct *tty, struct file *file, 493 unsigned int cmd, unsigned long arg) 494 { 495 switch (cmd) { 496 case TIOCSPTLCK: /* Set PT Lock (disallow slave open) */ 497 return pty_set_lock(tty, (int __user *)arg); 498 case TIOCGPTN: /* Get PT Number */ 499 return put_user(tty->index, (unsigned int __user *)arg); 500 case TIOCSIG: /* Send signal to other side of pty */ 501 return pty_signal(tty, (int) arg); 502 } 503 504 return -ENOIOCTLCMD; 505 } 506 507 /** 508 * ptm_unix98_lookup - find a pty master 509 * @driver: ptm 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 *ptm_unix98_lookup(struct tty_driver *driver, 517 struct inode *ptm_inode, int idx) 518 { 519 struct tty_struct *tty = devpts_get_tty(ptm_inode, idx); 520 if (tty) 521 tty = tty->link; 522 return tty; 523 } 524 525 /** 526 * pts_unix98_lookup - find a pty slave 527 * @driver: pts driver 528 * @idx: tty index 529 * 530 * Look up a pty master device. Called under the tty_mutex for now. 531 * This provides our locking. 532 */ 533 534 static struct tty_struct *pts_unix98_lookup(struct tty_driver *driver, 535 struct inode *pts_inode, int idx) 536 { 537 struct tty_struct *tty = devpts_get_tty(pts_inode, idx); 538 /* Master must be open before slave */ 539 if (!tty) 540 return ERR_PTR(-EIO); 541 return tty; 542 } 543 544 static void pty_unix98_shutdown(struct tty_struct *tty) 545 { 546 /* We have our own method as we don't use the tty index */ 547 kfree(tty->termios); 548 } 549 550 /* We have no need to install and remove our tty objects as devpts does all 551 the work for us */ 552 553 static int pty_unix98_install(struct tty_driver *driver, struct tty_struct *tty) 554 { 555 struct tty_struct *o_tty; 556 int idx = tty->index; 557 558 o_tty = alloc_tty_struct(); 559 if (!o_tty) 560 return -ENOMEM; 561 if (!try_module_get(driver->other->owner)) { 562 /* This cannot in fact currently happen */ 563 free_tty_struct(o_tty); 564 return -ENOMEM; 565 } 566 initialize_tty_struct(o_tty, driver->other, idx); 567 568 tty->termios = kzalloc(sizeof(struct ktermios[2]), GFP_KERNEL); 569 if (tty->termios == NULL) 570 goto free_mem_out; 571 *tty->termios = driver->init_termios; 572 tty->termios_locked = tty->termios + 1; 573 574 o_tty->termios = kzalloc(sizeof(struct ktermios[2]), GFP_KERNEL); 575 if (o_tty->termios == NULL) 576 goto free_mem_out; 577 *o_tty->termios = driver->other->init_termios; 578 o_tty->termios_locked = o_tty->termios + 1; 579 580 tty_driver_kref_get(driver->other); 581 if (driver->subtype == PTY_TYPE_MASTER) 582 o_tty->count++; 583 /* Establish the links in both directions */ 584 tty->link = o_tty; 585 o_tty->link = tty; 586 /* 587 * All structures have been allocated, so now we install them. 588 * Failures after this point use release_tty to clean up, so 589 * there's no need to null out the local pointers. 590 */ 591 tty_driver_kref_get(driver); 592 tty->count++; 593 pty_count++; 594 return 0; 595 free_mem_out: 596 kfree(o_tty->termios); 597 module_put(o_tty->driver->owner); 598 free_tty_struct(o_tty); 599 kfree(tty->termios); 600 return -ENOMEM; 601 } 602 603 static void pty_unix98_remove(struct tty_driver *driver, struct tty_struct *tty) 604 { 605 pty_count--; 606 } 607 608 static const struct tty_operations ptm_unix98_ops = { 609 .lookup = ptm_unix98_lookup, 610 .install = pty_unix98_install, 611 .remove = pty_unix98_remove, 612 .open = pty_open, 613 .close = pty_close, 614 .write = pty_write, 615 .write_room = pty_write_room, 616 .flush_buffer = pty_flush_buffer, 617 .chars_in_buffer = pty_chars_in_buffer, 618 .unthrottle = pty_unthrottle, 619 .set_termios = pty_set_termios, 620 .ioctl = pty_unix98_ioctl, 621 .shutdown = pty_unix98_shutdown, 622 .resize = pty_resize 623 }; 624 625 static const struct tty_operations pty_unix98_ops = { 626 .lookup = pts_unix98_lookup, 627 .install = pty_unix98_install, 628 .remove = pty_unix98_remove, 629 .open = pty_open, 630 .close = pty_close, 631 .write = pty_write, 632 .write_room = pty_write_room, 633 .flush_buffer = pty_flush_buffer, 634 .chars_in_buffer = pty_chars_in_buffer, 635 .unthrottle = pty_unthrottle, 636 .set_termios = pty_set_termios, 637 .shutdown = pty_unix98_shutdown 638 }; 639 640 /** 641 * ptmx_open - open a unix 98 pty master 642 * @inode: inode of device file 643 * @filp: file pointer to tty 644 * 645 * Allocate a unix98 pty master device from the ptmx driver. 646 * 647 * Locking: tty_mutex protects the init_dev work. tty->count should 648 * protect the rest. 649 * allocated_ptys_lock handles the list of free pty numbers 650 */ 651 652 static int ptmx_open(struct inode *inode, struct file *filp) 653 { 654 struct tty_struct *tty; 655 int retval; 656 int index; 657 658 nonseekable_open(inode, filp); 659 660 /* find a device that is not in use. */ 661 tty_lock(); 662 index = devpts_new_index(inode); 663 tty_unlock(); 664 if (index < 0) 665 return index; 666 667 mutex_lock(&tty_mutex); 668 tty_lock(); 669 tty = tty_init_dev(ptm_driver, index, 1); 670 mutex_unlock(&tty_mutex); 671 672 if (IS_ERR(tty)) { 673 retval = PTR_ERR(tty); 674 goto out; 675 } 676 677 set_bit(TTY_PTY_LOCK, &tty->flags); /* LOCK THE SLAVE */ 678 679 retval = tty_add_file(tty, filp); 680 if (retval) 681 goto out; 682 683 retval = devpts_pty_new(inode, tty->link); 684 if (retval) 685 goto out1; 686 687 retval = ptm_driver->ops->open(tty, filp); 688 if (retval) 689 goto out2; 690 out1: 691 tty_unlock(); 692 return retval; 693 out2: 694 tty_unlock(); 695 tty_release(inode, filp); 696 return retval; 697 out: 698 devpts_kill_index(inode, index); 699 tty_unlock(); 700 return retval; 701 } 702 703 static struct file_operations ptmx_fops; 704 705 static void __init unix98_pty_init(void) 706 { 707 ptm_driver = alloc_tty_driver(NR_UNIX98_PTY_MAX); 708 if (!ptm_driver) 709 panic("Couldn't allocate Unix98 ptm driver"); 710 pts_driver = alloc_tty_driver(NR_UNIX98_PTY_MAX); 711 if (!pts_driver) 712 panic("Couldn't allocate Unix98 pts driver"); 713 714 ptm_driver->owner = THIS_MODULE; 715 ptm_driver->driver_name = "pty_master"; 716 ptm_driver->name = "ptm"; 717 ptm_driver->major = UNIX98_PTY_MASTER_MAJOR; 718 ptm_driver->minor_start = 0; 719 ptm_driver->type = TTY_DRIVER_TYPE_PTY; 720 ptm_driver->subtype = PTY_TYPE_MASTER; 721 ptm_driver->init_termios = tty_std_termios; 722 ptm_driver->init_termios.c_iflag = 0; 723 ptm_driver->init_termios.c_oflag = 0; 724 ptm_driver->init_termios.c_cflag = B38400 | CS8 | CREAD; 725 ptm_driver->init_termios.c_lflag = 0; 726 ptm_driver->init_termios.c_ispeed = 38400; 727 ptm_driver->init_termios.c_ospeed = 38400; 728 ptm_driver->flags = TTY_DRIVER_RESET_TERMIOS | TTY_DRIVER_REAL_RAW | 729 TTY_DRIVER_DYNAMIC_DEV | TTY_DRIVER_DEVPTS_MEM; 730 ptm_driver->other = pts_driver; 731 tty_set_operations(ptm_driver, &ptm_unix98_ops); 732 733 pts_driver->owner = THIS_MODULE; 734 pts_driver->driver_name = "pty_slave"; 735 pts_driver->name = "pts"; 736 pts_driver->major = UNIX98_PTY_SLAVE_MAJOR; 737 pts_driver->minor_start = 0; 738 pts_driver->type = TTY_DRIVER_TYPE_PTY; 739 pts_driver->subtype = PTY_TYPE_SLAVE; 740 pts_driver->init_termios = tty_std_termios; 741 pts_driver->init_termios.c_cflag = B38400 | CS8 | CREAD; 742 pts_driver->init_termios.c_ispeed = 38400; 743 pts_driver->init_termios.c_ospeed = 38400; 744 pts_driver->flags = TTY_DRIVER_RESET_TERMIOS | TTY_DRIVER_REAL_RAW | 745 TTY_DRIVER_DYNAMIC_DEV | TTY_DRIVER_DEVPTS_MEM; 746 pts_driver->other = ptm_driver; 747 tty_set_operations(pts_driver, &pty_unix98_ops); 748 749 if (tty_register_driver(ptm_driver)) 750 panic("Couldn't register Unix98 ptm driver"); 751 if (tty_register_driver(pts_driver)) 752 panic("Couldn't register Unix98 pts driver"); 753 754 register_sysctl_table(pty_root_table); 755 756 /* Now create the /dev/ptmx special device */ 757 tty_default_fops(&ptmx_fops); 758 ptmx_fops.open = ptmx_open; 759 760 cdev_init(&ptmx_cdev, &ptmx_fops); 761 if (cdev_add(&ptmx_cdev, MKDEV(TTYAUX_MAJOR, 2), 1) || 762 register_chrdev_region(MKDEV(TTYAUX_MAJOR, 2), 1, "/dev/ptmx") < 0) 763 panic("Couldn't register /dev/ptmx driver\n"); 764 device_create(tty_class, NULL, MKDEV(TTYAUX_MAJOR, 2), NULL, "ptmx"); 765 } 766 767 #else 768 static inline void unix98_pty_init(void) { } 769 #endif 770 771 static int __init pty_init(void) 772 { 773 legacy_pty_init(); 774 unix98_pty_init(); 775 return 0; 776 } 777 module_init(pty_init); 778