tty.c revision 182471
1/*- 2 * Copyright (c) 2008 Ed Schouten <ed@FreeBSD.org> 3 * All rights reserved. 4 * 5 * Portions of this software were developed under sponsorship from Snow 6 * B.V., the Netherlands. 7 * 8 * Redistribution and use in source and binary forms, with or without 9 * modification, are permitted provided that the following conditions 10 * are met: 11 * 1. Redistributions of source code must retain the above copyright 12 * notice, this list of conditions and the following disclaimer. 13 * 2. Redistributions in binary form must reproduce the above copyright 14 * notice, this list of conditions and the following disclaimer in the 15 * documentation and/or other materials provided with the distribution. 16 * 17 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 18 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 19 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 20 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 21 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 22 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 23 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 24 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 25 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 26 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 27 * SUCH DAMAGE. 28 */ 29 30#include <sys/cdefs.h> 31__FBSDID("$FreeBSD: head/sys/kern/tty.c 182471 2008-08-30 09:18:27Z ed $"); 32 33#include "opt_compat.h" 34 35#include <sys/param.h> 36#include <sys/conf.h> 37#include <sys/cons.h> 38#include <sys/fcntl.h> 39#include <sys/filio.h> 40#ifdef COMPAT_43TTY 41#include <sys/ioctl_compat.h> 42#endif /* COMPAT_43TTY */ 43#include <sys/kernel.h> 44#include <sys/limits.h> 45#include <sys/malloc.h> 46#include <sys/mount.h> 47#include <sys/namei.h> 48#include <sys/poll.h> 49#include <sys/priv.h> 50#include <sys/proc.h> 51#include <sys/serial.h> 52#include <sys/signal.h> 53#include <sys/stat.h> 54#include <sys/sx.h> 55#include <sys/sysctl.h> 56#include <sys/systm.h> 57#include <sys/tty.h> 58#include <sys/ttycom.h> 59#define TTYDEFCHARS 60#include <sys/ttydefaults.h> 61#undef TTYDEFCHARS 62#include <sys/ucred.h> 63#include <sys/vnode.h> 64 65#include <machine/stdarg.h> 66 67static MALLOC_DEFINE(M_TTY, "tty", "tty device"); 68 69static void tty_rel_free(struct tty *tp); 70 71static TAILQ_HEAD(, tty) tty_list = TAILQ_HEAD_INITIALIZER(tty_list); 72static struct sx tty_list_sx; 73SX_SYSINIT(tty_list, &tty_list_sx, "tty list"); 74static unsigned int tty_list_count = 0; 75 76/* 77 * Flags that are supported and stored by this implementation. 78 */ 79#define TTYSUP_IFLAG (IGNBRK|BRKINT|IGNPAR|PARMRK|INPCK|ISTRIP|\ 80 INLCR|IGNCR|ICRNL|IXON|IXOFF|IXANY|IMAXBEL) 81#define TTYSUP_OFLAG (OPOST|ONLCR|TAB3|ONOEOT|OCRNL|ONOCR|ONLRET) 82#define TTYSUP_LFLAG (ECHOKE|ECHOE|ECHOK|ECHO|ECHONL|ECHOPRT|\ 83 ECHOCTL|ISIG|ICANON|ALTWERASE|IEXTEN|TOSTOP|\ 84 FLUSHO|NOKERNINFO|NOFLSH) 85#define TTYSUP_CFLAG (CIGNORE|CSIZE|CSTOPB|CREAD|PARENB|PARODD|\ 86 HUPCL|CLOCAL|CCTS_OFLOW|CRTS_IFLOW|CDTR_IFLOW|\ 87 CDSR_OFLOW|CCAR_OFLOW) 88 89#define TTY_CALLOUT(tp,d) ((tp)->t_dev != (d)) 90 91/* 92 * Set TTY buffer sizes. 93 */ 94 95static void 96tty_watermarks(struct tty *tp) 97{ 98 speed_t sp; 99 100 /* Provide an input buffer for 0.2 seconds of data. */ 101 sp = MAX(tp->t_termios.c_ispeed, 0); 102 ttyinq_setsize(&tp->t_inq, tp, sp / 5); 103 104 /* Set low watermark at 10% (when 90% is available). */ 105 tp->t_inlow = (ttyinq_getsize(&tp->t_inq) * 9) / 10; 106 107 /* Provide an ouput buffer for 0.2 seconds of data. */ 108 sp = MAX(tp->t_termios.c_ospeed, 0); 109 ttyoutq_setsize(&tp->t_outq, tp, sp / 5); 110 111 /* Set low watermark at 10% (when 90% is available). */ 112 tp->t_outlow = (ttyoutq_getsize(&tp->t_outq) * 9) / 10; 113} 114 115static int 116tty_drain(struct tty *tp) 117{ 118 int error; 119 120 while (ttyoutq_bytesused(&tp->t_outq) > 0) { 121 ttydevsw_outwakeup(tp); 122 /* Could be handled synchronously. */ 123 if (ttyoutq_bytesused(&tp->t_outq) == 0) 124 return (0); 125 126 /* Wait for data to be drained. */ 127 error = tty_wait(tp, &tp->t_outwait); 128 if (error) 129 return (error); 130 } 131 132 return (0); 133} 134 135/* 136 * Because the revoke() call already calls d_close() without making sure 137 * all threads are purged from the TTY, we can only destroy the buffers 138 * and such when the last thread leaves the TTY. ttydev_enter() and 139 * ttydev_leave() are called from within the cdev functions, to make 140 * sure we can garbage collect the TTY. 141 */ 142 143static __inline int 144ttydev_enter(struct tty *tp) 145{ 146 tty_lock(tp); 147 148 if (tty_gone(tp) || !tty_opened(tp)) { 149 /* Device is already gone. */ 150 tty_unlock(tp); 151 return (ENXIO); 152 } 153 154 return (0); 155} 156 157static void 158ttydev_leave(struct tty *tp) 159{ 160 tty_lock_assert(tp, MA_OWNED); 161 162 if (tty_opened(tp) || tp->t_flags & TF_OPENCLOSE) { 163 /* Device is still opened somewhere. */ 164 tty_unlock(tp); 165 return; 166 } 167 168 tp->t_flags |= TF_OPENCLOSE; 169 170 /* Stop asynchronous I/O. */ 171 funsetown(&tp->t_sigio); 172 173 /* Remove console TTY. */ 174 if (constty == tp) 175 constty_clear(); 176 177 /* Drain any output. */ 178 MPASS((tp->t_flags & TF_STOPPED) == 0); 179 if (!tty_gone(tp)) 180 tty_drain(tp); 181 182 ttydisc_close(tp); 183 184 /* Destroy associated buffers already. */ 185 ttyinq_free(&tp->t_inq); 186 tp->t_inlow = 0; 187 ttyoutq_free(&tp->t_outq); 188 tp->t_outlow = 0; 189 190 knlist_clear(&tp->t_inpoll.si_note, 1); 191 knlist_clear(&tp->t_outpoll.si_note, 1); 192 193 if (!tty_gone(tp)) 194 ttydevsw_close(tp); 195 196 tp->t_flags &= ~TF_OPENCLOSE; 197 tty_rel_free(tp); 198} 199 200/* 201 * Operations that are exposed through the character device in /dev. 202 */ 203static int 204ttydev_open(struct cdev *dev, int oflags, int devtype, struct thread *td) 205{ 206 struct tty *tp = dev->si_drv1; 207 int error; 208 209 /* Disallow access when the TTY belongs to a different prison. */ 210 if (dev->si_cred != NULL && 211 dev->si_cred->cr_prison != td->td_ucred->cr_prison && 212 priv_check(td, PRIV_TTY_PRISON)) { 213 return (EPERM); 214 } 215 216 tty_lock(tp); 217 if (tty_gone(tp)) { 218 /* Device is already gone. */ 219 tty_unlock(tp); 220 return (ENXIO); 221 } 222 /* 223 * Prevent the TTY from being opened when being torn down or 224 * built up by unrelated processes. 225 */ 226 if (tp->t_flags & TF_OPENCLOSE) { 227 tty_unlock(tp); 228 return (EBUSY); 229 } 230 tp->t_flags |= TF_OPENCLOSE; 231 232 /* 233 * Make sure the "tty" and "cua" device cannot be opened at the 234 * same time. 235 */ 236 if (TTY_CALLOUT(tp, dev)) { 237 if (tp->t_flags & TF_OPENED_IN) { 238 error = EBUSY; 239 goto done; 240 } 241 } else { 242 if (tp->t_flags & TF_OPENED_OUT) { 243 error = EBUSY; 244 goto done; 245 } 246 } 247 248 if (tp->t_flags & TF_EXCLUDE && priv_check(td, PRIV_TTY_EXCLUSIVE)) { 249 error = EBUSY; 250 goto done; 251 } 252 253 if (!tty_opened(tp)) { 254 /* Set proper termios flags. */ 255 if (TTY_CALLOUT(tp, dev)) { 256 tp->t_termios = tp->t_termios_init_out; 257 } else { 258 tp->t_termios = tp->t_termios_init_in; 259 } 260 ttydevsw_param(tp, &tp->t_termios); 261 262 ttydevsw_modem(tp, SER_DTR|SER_RTS, 0); 263 264 error = ttydevsw_open(tp); 265 if (error != 0) 266 goto done; 267 268 ttydisc_open(tp); 269 tty_watermarks(tp); 270 } 271 272 /* Wait for Carrier Detect. */ 273 if (!TTY_CALLOUT(tp, dev) && (oflags & O_NONBLOCK) == 0 && 274 (tp->t_termios.c_cflag & CLOCAL) == 0) { 275 while ((ttydevsw_modem(tp, 0, 0) & SER_DCD) == 0) { 276 error = tty_wait(tp, &tp->t_dcdwait); 277 if (error != 0) 278 goto done; 279 } 280 } 281 282 if (TTY_CALLOUT(tp, dev)) { 283 tp->t_flags |= TF_OPENED_OUT; 284 } else { 285 tp->t_flags |= TF_OPENED_IN; 286 } 287 288done: tp->t_flags &= ~TF_OPENCLOSE; 289 ttydev_leave(tp); 290 return (error); 291} 292 293static int 294ttydev_close(struct cdev *dev, int fflag, int devtype, struct thread *td) 295{ 296 struct tty *tp = dev->si_drv1; 297 298 tty_lock(tp); 299 300 /* 301 * This can only be called once. The callin and the callout 302 * devices cannot be opened at the same time. 303 */ 304 MPASS((tp->t_flags & TF_OPENED) != TF_OPENED); 305 tp->t_flags &= ~(TF_OPENED|TF_EXCLUDE|TF_STOPPED); 306 307 /* Properly wake up threads that are stuck - revoke(). */ 308 tp->t_revokecnt++; 309 tty_wakeup(tp, FREAD|FWRITE); 310 cv_broadcast(&tp->t_bgwait); 311 312 ttydev_leave(tp); 313 314 return (0); 315} 316 317static __inline int 318tty_is_ctty(struct tty *tp, struct proc *p) 319{ 320 tty_lock_assert(tp, MA_OWNED); 321 322 return (p->p_session == tp->t_session && p->p_flag & P_CONTROLT); 323} 324 325static int 326tty_wait_background(struct tty *tp, struct thread *td, int sig) 327{ 328 struct proc *p = td->td_proc; 329 struct pgrp *pg; 330 int error; 331 332 MPASS(sig == SIGTTIN || sig == SIGTTOU); 333 tty_lock_assert(tp, MA_OWNED); 334 335 for (;;) { 336 PROC_LOCK(p); 337 /* 338 * The process should only sleep, when: 339 * - This terminal is the controling terminal 340 * - Its process group is not the foreground process 341 * group 342 * - The parent process isn't waiting for the child to 343 * exit 344 * - the signal to send to the process isn't masked 345 */ 346 if (!tty_is_ctty(tp, p) || 347 p->p_pgrp == tp->t_pgrp || p->p_flag & P_PPWAIT || 348 SIGISMEMBER(p->p_sigacts->ps_sigignore, sig) || 349 SIGISMEMBER(td->td_sigmask, sig)) { 350 /* Allow the action to happen. */ 351 PROC_UNLOCK(p); 352 return (0); 353 } 354 355 /* 356 * Send the signal and sleep until we're the new 357 * foreground process group. 358 */ 359 pg = p->p_pgrp; 360 PROC_UNLOCK(p); 361 if (pg->pg_jobc == 0) 362 return (EIO); 363 PGRP_LOCK(pg); 364 pgsignal(pg, sig, 1); 365 PGRP_UNLOCK(pg); 366 367 error = tty_wait(tp, &tp->t_bgwait); 368 if (error) 369 return (error); 370 } 371} 372 373static int 374ttydev_read(struct cdev *dev, struct uio *uio, int ioflag) 375{ 376 struct tty *tp = dev->si_drv1; 377 int error; 378 379 error = ttydev_enter(tp); 380 if (error) 381 return (0); 382 383 error = tty_wait_background(tp, curthread, SIGTTIN); 384 if (error) 385 goto done; 386 387 error = ttydisc_read(tp, uio, ioflag); 388done: ttydev_leave(tp); 389 390 /* 391 * The read() and write() calls should not throw an error when 392 * the device is ripped offline. 393 */ 394 if (error == ENXIO) 395 return (0); 396 397 return (error); 398} 399 400static int 401ttydev_write(struct cdev *dev, struct uio *uio, int ioflag) 402{ 403 struct tty *tp = dev->si_drv1; 404 int error; 405 406 error = ttydev_enter(tp); 407 if (error) 408 return (0); 409 410 if (tp->t_termios.c_lflag & TOSTOP) { 411 error = tty_wait_background(tp, curthread, SIGTTOU); 412 if (error) 413 goto done; 414 } 415 416 error = ttydisc_write(tp, uio, ioflag); 417done: ttydev_leave(tp); 418 419 /* 420 * The read() and write() calls should not throw an error when 421 * the device is ripped offline. 422 */ 423 if (error == ENXIO) 424 return (0); 425 426 return (error); 427} 428 429static int 430ttydev_ioctl(struct cdev *dev, u_long cmd, caddr_t data, int fflag, 431 struct thread *td) 432{ 433 struct tty *tp = dev->si_drv1; 434 int error; 435 436 error = ttydev_enter(tp); 437 if (error) 438 return (error); 439 440 switch (cmd) { 441 case TIOCCBRK: 442 case TIOCCONS: 443 case TIOCDRAIN: 444 case TIOCEXCL: 445 case TIOCFLUSH: 446 case TIOCNXCL: 447 case TIOCSBRK: 448 case TIOCSCTTY: 449 case TIOCSETA: 450 case TIOCSETAF: 451 case TIOCSETAW: 452 case TIOCSPGRP: 453 case TIOCSTART: 454 case TIOCSTAT: 455 case TIOCSTOP: 456 case TIOCSWINSZ: 457#if 0 458 case TIOCSDRAINWAIT: 459 case TIOCSETD: 460 case TIOCSTI: 461#endif 462#ifdef COMPAT_43TTY 463 case TIOCLBIC: 464 case TIOCLBIS: 465 case TIOCLSET: 466 case TIOCSETC: 467 case OTIOCSETD: 468 case TIOCSETN: 469 case TIOCSETP: 470 case TIOCSLTC: 471#endif /* COMPAT_43TTY */ 472 /* 473 * If the ioctl() causes the TTY to be modified, let it 474 * wait in the background. 475 */ 476 error = tty_wait_background(tp, curthread, SIGTTOU); 477 if (error) 478 goto done; 479 } 480 481 error = tty_ioctl(tp, cmd, data, td); 482done: ttydev_leave(tp); 483 484 return (error); 485} 486 487static int 488ttydev_poll(struct cdev *dev, int events, struct thread *td) 489{ 490 struct tty *tp = dev->si_drv1; 491 int error, revents = 0; 492 493 error = ttydev_enter(tp); 494 if (error) { 495 /* Don't return the error here, but the event mask. */ 496 return (events & 497 (POLLHUP|POLLIN|POLLRDNORM|POLLOUT|POLLWRNORM)); 498 } 499 500 if (events & (POLLIN|POLLRDNORM)) { 501 /* See if we can read something. */ 502 if (ttydisc_read_poll(tp) > 0) 503 revents |= events & (POLLIN|POLLRDNORM); 504 } 505 if (events & (POLLOUT|POLLWRNORM)) { 506 /* See if we can write something. */ 507 if (ttydisc_write_poll(tp) > 0) 508 revents |= events & (POLLOUT|POLLWRNORM); 509 } 510 if (tp->t_flags & TF_ZOMBIE) 511 /* Hangup flag on zombie state. */ 512 revents |= events & POLLHUP; 513 514 if (revents == 0) { 515 if (events & (POLLIN|POLLRDNORM)) 516 selrecord(td, &tp->t_inpoll); 517 if (events & (POLLOUT|POLLWRNORM)) 518 selrecord(td, &tp->t_outpoll); 519 } 520 521 ttydev_leave(tp); 522 523 return (revents); 524} 525 526static int 527ttydev_mmap(struct cdev *dev, vm_offset_t offset, vm_paddr_t *paddr, int nprot) 528{ 529 struct tty *tp = dev->si_drv1; 530 int error; 531 532 /* Handle mmap() through the driver. */ 533 534 error = ttydev_enter(tp); 535 if (error) 536 return (-1); 537 error = ttydevsw_mmap(tp, offset, paddr, nprot); 538 ttydev_leave(tp); 539 540 return (error); 541} 542 543/* 544 * kqueue support. 545 */ 546 547static void 548tty_kqops_read_detach(struct knote *kn) 549{ 550 struct tty *tp = kn->kn_hook; 551 552 knlist_remove(&tp->t_inpoll.si_note, kn, 0); 553} 554 555static int 556tty_kqops_read_event(struct knote *kn, long hint) 557{ 558 struct tty *tp = kn->kn_hook; 559 560 tty_lock_assert(tp, MA_OWNED); 561 562 if (tty_gone(tp) || tp->t_flags & TF_ZOMBIE) { 563 kn->kn_flags |= EV_EOF; 564 return (1); 565 } else { 566 kn->kn_data = ttydisc_read_poll(tp); 567 return (kn->kn_data > 0); 568 } 569} 570 571static void 572tty_kqops_write_detach(struct knote *kn) 573{ 574 struct tty *tp = kn->kn_hook; 575 576 knlist_remove(&tp->t_outpoll.si_note, kn, 0); 577} 578 579static int 580tty_kqops_write_event(struct knote *kn, long hint) 581{ 582 struct tty *tp = kn->kn_hook; 583 584 tty_lock_assert(tp, MA_OWNED); 585 586 if (tty_gone(tp)) { 587 kn->kn_flags |= EV_EOF; 588 return (1); 589 } else { 590 kn->kn_data = ttydisc_write_poll(tp); 591 return (kn->kn_data > 0); 592 } 593} 594 595static struct filterops tty_kqops_read = 596 { 1, NULL, tty_kqops_read_detach, tty_kqops_read_event }; 597static struct filterops tty_kqops_write = 598 { 1, NULL, tty_kqops_write_detach, tty_kqops_write_event }; 599 600static int 601ttydev_kqfilter(struct cdev *dev, struct knote *kn) 602{ 603 struct tty *tp = dev->si_drv1; 604 int error; 605 606 error = ttydev_enter(tp); 607 if (error) 608 return (error); 609 610 switch (kn->kn_filter) { 611 case EVFILT_READ: 612 kn->kn_hook = tp; 613 kn->kn_fop = &tty_kqops_read; 614 knlist_add(&tp->t_inpoll.si_note, kn, 1); 615 break; 616 case EVFILT_WRITE: 617 kn->kn_hook = tp; 618 kn->kn_fop = &tty_kqops_write; 619 knlist_add(&tp->t_outpoll.si_note, kn, 1); 620 break; 621 default: 622 error = EINVAL; 623 break; 624 } 625 626 ttydev_leave(tp); 627 return (error); 628} 629 630static struct cdevsw ttydev_cdevsw = { 631 .d_version = D_VERSION, 632 .d_open = ttydev_open, 633 .d_close = ttydev_close, 634 .d_read = ttydev_read, 635 .d_write = ttydev_write, 636 .d_ioctl = ttydev_ioctl, 637 .d_kqfilter = ttydev_kqfilter, 638 .d_poll = ttydev_poll, 639 .d_mmap = ttydev_mmap, 640 .d_name = "ttydev", 641 .d_flags = D_TTY, 642}; 643 644/* 645 * Init/lock-state devices 646 */ 647 648static int 649ttyil_open(struct cdev *dev, int oflags, int devtype, struct thread *td) 650{ 651 struct tty *tp = dev->si_drv1; 652 int error = 0; 653 654 tty_lock(tp); 655 if (tty_gone(tp)) 656 error = ENODEV; 657 tty_unlock(tp); 658 659 return (error); 660} 661 662static int 663ttyil_close(struct cdev *dev, int flag, int mode, struct thread *td) 664{ 665 return (0); 666} 667 668static int 669ttyil_rdwr(struct cdev *dev, struct uio *uio, int ioflag) 670{ 671 return (ENODEV); 672} 673 674static int 675ttyil_ioctl(struct cdev *dev, u_long cmd, caddr_t data, int fflag, 676 struct thread *td) 677{ 678 struct tty *tp = dev->si_drv1; 679 int error = 0; 680 681 tty_lock(tp); 682 if (tty_gone(tp)) { 683 error = ENODEV; 684 goto done; 685 } 686 687 switch (cmd) { 688 case TIOCGETA: 689 /* Obtain terminal flags through tcgetattr(). */ 690 bcopy(dev->si_drv2, data, sizeof(struct termios)); 691 break; 692 case TIOCSETA: 693 /* Set terminal flags through tcsetattr(). */ 694 error = priv_check(td, PRIV_TTY_SETA); 695 if (error) 696 break; 697 bcopy(data, dev->si_drv2, sizeof(struct termios)); 698 break; 699 case TIOCGETD: 700 *(int *)data = TTYDISC; 701 break; 702 case TIOCGWINSZ: 703 bzero(data, sizeof(struct winsize)); 704 break; 705 default: 706 error = ENOTTY; 707 } 708 709done: tty_unlock(tp); 710 return (error); 711} 712 713static struct cdevsw ttyil_cdevsw = { 714 .d_version = D_VERSION, 715 .d_open = ttyil_open, 716 .d_close = ttyil_close, 717 .d_read = ttyil_rdwr, 718 .d_write = ttyil_rdwr, 719 .d_ioctl = ttyil_ioctl, 720 .d_name = "ttyil", 721 .d_flags = D_TTY, 722}; 723 724static void 725tty_init_termios(struct tty *tp) 726{ 727 struct termios *t = &tp->t_termios_init_in; 728 729 t->c_cflag = TTYDEF_CFLAG; 730 t->c_iflag = TTYDEF_IFLAG; 731 t->c_lflag = TTYDEF_LFLAG; 732 t->c_oflag = TTYDEF_OFLAG; 733 t->c_ispeed = TTYDEF_SPEED; 734 t->c_ospeed = TTYDEF_SPEED; 735 bcopy(ttydefchars, &t->c_cc, sizeof ttydefchars); 736 737 tp->t_termios_init_out = *t; 738} 739 740void 741tty_init_console(struct tty *tp, speed_t s) 742{ 743 struct termios *ti = &tp->t_termios_init_in; 744 struct termios *to = &tp->t_termios_init_out; 745 746 if (s != 0) { 747 ti->c_ispeed = ti->c_ospeed = s; 748 to->c_ispeed = to->c_ospeed = s; 749 } 750 751 ti->c_cflag |= CLOCAL; 752 to->c_cflag |= CLOCAL; 753} 754 755/* 756 * Standard device routine implementations, mostly meant for 757 * pseudo-terminal device drivers. When a driver creates a new terminal 758 * device class, missing routines are patched. 759 */ 760 761static int 762ttydevsw_defopen(struct tty *tp) 763{ 764 765 return (0); 766} 767 768static void 769ttydevsw_defclose(struct tty *tp) 770{ 771} 772 773static void 774ttydevsw_defoutwakeup(struct tty *tp) 775{ 776 777 panic("Terminal device has output, while not implemented"); 778} 779 780static void 781ttydevsw_definwakeup(struct tty *tp) 782{ 783} 784 785static int 786ttydevsw_defioctl(struct tty *tp, u_long cmd, caddr_t data, struct thread *td) 787{ 788 789 return (ENOIOCTL); 790} 791 792static int 793ttydevsw_defparam(struct tty *tp, struct termios *t) 794{ 795 796 /* Use a fake baud rate, we're not a real device. */ 797 t->c_ispeed = t->c_ospeed = TTYDEF_SPEED_PSEUDO; 798 799 return (0); 800} 801 802static int 803ttydevsw_defmodem(struct tty *tp, int sigon, int sigoff) 804{ 805 806 /* Simulate a carrier to make the TTY layer happy. */ 807 return (SER_DCD); 808} 809 810static int 811ttydevsw_defmmap(struct tty *tp, vm_offset_t offset, vm_paddr_t *paddr, 812 int nprot) 813{ 814 815 return (-1); 816} 817 818static void 819ttydevsw_deffree(void *softc) 820{ 821 822 panic("Terminal device freed without a free-handler"); 823} 824 825/* 826 * TTY allocation and deallocation. TTY devices can be deallocated when 827 * the driver doesn't use it anymore, when the TTY isn't a session's 828 * controlling TTY and when the device node isn't opened through devfs. 829 */ 830 831struct tty * 832tty_alloc(struct ttydevsw *tsw, void *sc, struct mtx *mutex) 833{ 834 struct tty *tp; 835 836 /* Make sure the driver defines all routines. */ 837#define PATCH_FUNC(x) do { \ 838 if (tsw->tsw_ ## x == NULL) \ 839 tsw->tsw_ ## x = ttydevsw_def ## x; \ 840} while (0) 841 PATCH_FUNC(open); 842 PATCH_FUNC(close); 843 PATCH_FUNC(outwakeup); 844 PATCH_FUNC(inwakeup); 845 PATCH_FUNC(ioctl); 846 PATCH_FUNC(param); 847 PATCH_FUNC(modem); 848 PATCH_FUNC(mmap); 849 PATCH_FUNC(free); 850#undef PATCH_FUNC 851 852 tp = malloc(sizeof(struct tty), M_TTY, M_WAITOK|M_ZERO); 853 tp->t_devsw = tsw; 854 tp->t_softc = sc; 855 tp->t_flags = tsw->tsw_flags; 856 857 tty_init_termios(tp); 858 859 cv_init(&tp->t_inwait, "tty input"); 860 cv_init(&tp->t_outwait, "tty output"); 861 cv_init(&tp->t_bgwait, "tty background"); 862 cv_init(&tp->t_dcdwait, "tty dcd"); 863 864 ttyinq_init(&tp->t_inq); 865 ttyoutq_init(&tp->t_outq); 866 867 /* Allow drivers to use a custom mutex to lock the TTY. */ 868 if (mutex != NULL) { 869 tp->t_mtx = mutex; 870 } else { 871 tp->t_mtx = &tp->t_mtxobj; 872 mtx_init(&tp->t_mtxobj, "tty lock", NULL, MTX_DEF); 873 } 874 875 knlist_init(&tp->t_inpoll.si_note, tp->t_mtx, NULL, NULL, NULL); 876 knlist_init(&tp->t_outpoll.si_note, tp->t_mtx, NULL, NULL, NULL); 877 878 sx_xlock(&tty_list_sx); 879 TAILQ_INSERT_TAIL(&tty_list, tp, t_list); 880 tty_list_count++; 881 sx_xunlock(&tty_list_sx); 882 883 return (tp); 884} 885 886static void 887tty_dealloc(void *arg) 888{ 889 struct tty *tp = arg; 890 891 sx_xlock(&tty_list_sx); 892 TAILQ_REMOVE(&tty_list, tp, t_list); 893 tty_list_count--; 894 sx_xunlock(&tty_list_sx); 895 896 /* Make sure we haven't leaked buffers. */ 897 MPASS(ttyinq_getsize(&tp->t_inq) == 0); 898 MPASS(ttyoutq_getsize(&tp->t_outq) == 0); 899 900 knlist_destroy(&tp->t_inpoll.si_note); 901 knlist_destroy(&tp->t_outpoll.si_note); 902 903 cv_destroy(&tp->t_inwait); 904 cv_destroy(&tp->t_outwait); 905 cv_destroy(&tp->t_bgwait); 906 cv_destroy(&tp->t_dcdwait); 907 908 if (tp->t_mtx == &tp->t_mtxobj) 909 mtx_destroy(&tp->t_mtxobj); 910 ttydevsw_free(tp); 911 free(tp, M_TTY); 912} 913 914static void 915tty_rel_free(struct tty *tp) 916{ 917 struct cdev *dev; 918 919 tty_lock_assert(tp, MA_OWNED); 920 921 if (tp->t_sessioncnt != 0 || 922 (tp->t_flags & (TF_GONE|TF_OPENED)) != TF_GONE) { 923 /* TTY is still in use. */ 924 tty_unlock(tp); 925 return; 926 } 927 928 /* TTY can be deallocated. */ 929 dev = tp->t_dev; 930 tp->t_dev = NULL; 931 tty_unlock(tp); 932 933 destroy_dev_sched_cb(dev, tty_dealloc, tp); 934} 935 936void 937tty_rel_pgrp(struct tty *tp, struct pgrp *pg) 938{ 939 tty_lock_assert(tp, MA_OWNED); 940 941 if (tp->t_pgrp == pg) 942 tp->t_pgrp = NULL; 943} 944 945void 946tty_rel_sess(struct tty *tp, struct session *sess) 947{ 948 MPASS(tp->t_sessioncnt > 0); 949 950 /* Current session has left. */ 951 if (tp->t_session == sess) { 952 tp->t_session = NULL; 953 MPASS(tp->t_pgrp == NULL); 954 } 955 tp->t_sessioncnt--; 956 tty_rel_free(tp); 957} 958 959void 960tty_rel_gone(struct tty *tp) 961{ 962 MPASS(!tty_gone(tp)); 963 964 /* Simulate carrier removal. */ 965 ttydisc_modem(tp, 0); 966 967 /* Wake up misc. blocked threads. */ 968 cv_broadcast(&tp->t_bgwait); 969 cv_broadcast(&tp->t_dcdwait); 970 971 tp->t_flags |= TF_GONE; 972 tty_rel_free(tp); 973} 974 975/* 976 * Exposing information about current TTY's through sysctl 977 */ 978 979static void 980tty_to_xtty(struct tty *tp, struct xtty *xt) 981{ 982 tty_lock_assert(tp, MA_OWNED); 983 984 xt->xt_size = sizeof(struct xtty); 985 xt->xt_insize = ttyinq_getsize(&tp->t_inq); 986 xt->xt_incc = ttyinq_bytescanonicalized(&tp->t_inq); 987 xt->xt_inlc = ttyinq_bytesline(&tp->t_inq); 988 xt->xt_inlow = tp->t_inlow; 989 xt->xt_outsize = ttyoutq_getsize(&tp->t_outq); 990 xt->xt_outcc = ttyoutq_bytesused(&tp->t_outq); 991 xt->xt_outlow = tp->t_outlow; 992 xt->xt_column = tp->t_column; 993 xt->xt_pgid = tp->t_pgrp ? tp->t_pgrp->pg_id : 0; 994 xt->xt_sid = tp->t_session ? tp->t_session->s_sid : 0; 995 xt->xt_flags = tp->t_flags; 996 xt->xt_dev = tp->t_dev ? dev2udev(tp->t_dev) : NODEV; 997} 998 999static int 1000sysctl_kern_ttys(SYSCTL_HANDLER_ARGS) 1001{ 1002 unsigned long lsize; 1003 struct xtty *xtlist, *xt; 1004 struct tty *tp; 1005 int error; 1006 1007 sx_slock(&tty_list_sx); 1008 lsize = tty_list_count * sizeof(struct xtty); 1009 if (lsize == 0) { 1010 sx_sunlock(&tty_list_sx); 1011 return (0); 1012 } 1013 1014 xtlist = xt = malloc(lsize, M_TEMP, M_WAITOK); 1015 1016 TAILQ_FOREACH(tp, &tty_list, t_list) { 1017 tty_lock(tp); 1018 tty_to_xtty(tp, xt); 1019 tty_unlock(tp); 1020 xt++; 1021 } 1022 sx_sunlock(&tty_list_sx); 1023 1024 error = SYSCTL_OUT(req, xtlist, lsize); 1025 free(xtlist, M_TEMP); 1026 return (error); 1027} 1028 1029SYSCTL_PROC(_kern, OID_AUTO, ttys, CTLTYPE_OPAQUE|CTLFLAG_RD, 1030 0, 0, sysctl_kern_ttys, "S,xtty", "List of TTYs"); 1031 1032/* 1033 * Device node creation. Device has been set up, now we can expose it to 1034 * the user. 1035 */ 1036 1037void 1038tty_makedev(struct tty *tp, struct ucred *cred, const char *fmt, ...) 1039{ 1040 va_list ap; 1041 struct cdev *dev; 1042 const char *prefix = "tty"; 1043 char name[SPECNAMELEN - 3]; /* for "tty" and "cua". */ 1044 uid_t uid; 1045 gid_t gid; 1046 mode_t mode; 1047 1048 /* Remove "tty" prefix from devices like PTY's. */ 1049 if (tp->t_flags & TF_NOPREFIX) 1050 prefix = ""; 1051 1052 va_start(ap, fmt); 1053 vsnrprintf(name, sizeof name, 32, fmt, ap); 1054 va_end(ap); 1055 1056 if (cred == NULL) { 1057 /* System device. */ 1058 uid = UID_ROOT; 1059 gid = GID_WHEEL; 1060 mode = S_IRUSR|S_IWUSR; 1061 } else { 1062 /* User device. */ 1063 uid = cred->cr_ruid; 1064 gid = GID_TTY; 1065 mode = S_IRUSR|S_IWUSR|S_IWGRP; 1066 } 1067 1068 /* Master call-in device. */ 1069 dev = make_dev_cred(&ttydev_cdevsw, 0, cred, 1070 uid, gid, mode, "%s%s", prefix, name); 1071 dev->si_drv1 = tp; 1072 tp->t_dev = dev; 1073 1074 /* Slave call-in devices. */ 1075 if (tp->t_flags & TF_INITLOCK) { 1076 dev = make_dev_cred(&ttyil_cdevsw, 0, cred, 1077 uid, gid, mode, "%s%s.init", prefix, name); 1078 dev_depends(tp->t_dev, dev); 1079 dev->si_drv1 = tp; 1080 dev->si_drv2 = &tp->t_termios_init_in; 1081 1082 dev = make_dev_cred(&ttyil_cdevsw, 0, cred, 1083 uid, gid, mode, "%s%s.lock", prefix, name); 1084 dev_depends(tp->t_dev, dev); 1085 dev->si_drv1 = tp; 1086 dev->si_drv2 = &tp->t_termios_lock_in; 1087 } 1088 1089 /* Call-out devices. */ 1090 if (tp->t_flags & TF_CALLOUT) { 1091 dev = make_dev_cred(&ttydev_cdevsw, 0, cred, 1092 UID_UUCP, GID_DIALER, 0660, "cua%s", name); 1093 dev_depends(tp->t_dev, dev); 1094 dev->si_drv1 = tp; 1095 1096 /* Slave call-out devices. */ 1097 if (tp->t_flags & TF_INITLOCK) { 1098 dev = make_dev_cred(&ttyil_cdevsw, 0, cred, 1099 UID_UUCP, GID_DIALER, 0660, "cua%s.init", name); 1100 dev_depends(tp->t_dev, dev); 1101 dev->si_drv1 = tp; 1102 dev->si_drv2 = &tp->t_termios_init_out; 1103 1104 dev = make_dev_cred(&ttyil_cdevsw, 0, cred, 1105 UID_UUCP, GID_DIALER, 0660, "cua%s.lock", name); 1106 dev_depends(tp->t_dev, dev); 1107 dev->si_drv1 = tp; 1108 dev->si_drv2 = &tp->t_termios_lock_out; 1109 } 1110 } 1111} 1112 1113/* 1114 * Signalling processes. 1115 */ 1116 1117void 1118tty_signal_sessleader(struct tty *tp, int sig) 1119{ 1120 struct proc *p; 1121 1122 tty_lock_assert(tp, MA_OWNED); 1123 MPASS(sig >= 1 && sig < NSIG); 1124 1125 /* Make signals start output again. */ 1126 tp->t_flags &= ~TF_STOPPED; 1127 1128 if (tp->t_session != NULL && tp->t_session->s_leader != NULL) { 1129 p = tp->t_session->s_leader; 1130 PROC_LOCK(p); 1131 psignal(p, sig); 1132 PROC_UNLOCK(p); 1133 } 1134} 1135 1136void 1137tty_signal_pgrp(struct tty *tp, int sig) 1138{ 1139 tty_lock_assert(tp, MA_OWNED); 1140 MPASS(sig >= 1 && sig < NSIG); 1141 1142 /* Make signals start output again. */ 1143 tp->t_flags &= ~TF_STOPPED; 1144 1145 if (sig == SIGINFO && !(tp->t_termios.c_lflag & NOKERNINFO)) 1146 tty_info(tp); 1147 if (tp->t_pgrp != NULL) { 1148 PGRP_LOCK(tp->t_pgrp); 1149 pgsignal(tp->t_pgrp, sig, 1); 1150 PGRP_UNLOCK(tp->t_pgrp); 1151 } 1152} 1153 1154void 1155tty_wakeup(struct tty *tp, int flags) 1156{ 1157 if (tp->t_flags & TF_ASYNC && tp->t_sigio != NULL) 1158 pgsigio(&tp->t_sigio, SIGIO, (tp->t_session != NULL)); 1159 1160 if (flags & FWRITE) { 1161 cv_broadcast(&tp->t_outwait); 1162 selwakeup(&tp->t_outpoll); 1163 KNOTE_LOCKED(&tp->t_outpoll.si_note, 0); 1164 } 1165 if (flags & FREAD) { 1166 cv_broadcast(&tp->t_inwait); 1167 selwakeup(&tp->t_inpoll); 1168 KNOTE_LOCKED(&tp->t_inpoll.si_note, 0); 1169 } 1170} 1171 1172int 1173tty_wait(struct tty *tp, struct cv *cv) 1174{ 1175 int error; 1176 int revokecnt = tp->t_revokecnt; 1177 1178#if 0 1179 /* XXX: /dev/console also picks up Giant. */ 1180 tty_lock_assert(tp, MA_OWNED|MA_NOTRECURSED); 1181#endif 1182 tty_lock_assert(tp, MA_OWNED); 1183 1184 error = cv_wait_sig(cv, tp->t_mtx); 1185 1186 /* Restart the system call when we may have been revoked. */ 1187 if (tp->t_revokecnt != revokecnt) 1188 return (ERESTART); 1189 1190 /* Bail out when the device slipped away. */ 1191 if (tty_gone(tp)) 1192 return (ENXIO); 1193 1194 return (error); 1195} 1196 1197int 1198tty_timedwait(struct tty *tp, struct cv *cv, int hz) 1199{ 1200 int error; 1201 int revokecnt = tp->t_revokecnt; 1202 1203#if 0 1204 /* XXX: /dev/console also picks up Giant. */ 1205 tty_lock_assert(tp, MA_OWNED|MA_NOTRECURSED); 1206#endif 1207 tty_lock_assert(tp, MA_OWNED); 1208 1209 error = cv_timedwait_sig(cv, tp->t_mtx, hz); 1210 1211 /* Restart the system call when we may have been revoked. */ 1212 if (tp->t_revokecnt != revokecnt) 1213 return (ERESTART); 1214 1215 /* Bail out when the device slipped away. */ 1216 if (tty_gone(tp)) 1217 return (ENXIO); 1218 1219 return (error); 1220} 1221 1222void 1223tty_flush(struct tty *tp, int flags) 1224{ 1225 if (flags & FWRITE) { 1226 tp->t_flags &= ~TF_HIWAT_OUT; 1227 ttyoutq_flush(&tp->t_outq); 1228 tty_wakeup(tp, FWRITE); 1229 } 1230 if (flags & FREAD) { 1231 tty_hiwat_in_unblock(tp); 1232 ttyinq_flush(&tp->t_inq); 1233 ttydevsw_inwakeup(tp); 1234 } 1235} 1236 1237static int 1238tty_generic_ioctl(struct tty *tp, u_long cmd, void *data, struct thread *td) 1239{ 1240 int error; 1241 1242 switch (cmd) { 1243 /* 1244 * Modem commands. 1245 * The SER_* and TIOCM_* flags are the same, but one bit 1246 * shifted. I don't know why. 1247 */ 1248 case TIOCSDTR: 1249 ttydevsw_modem(tp, SER_DTR, 0); 1250 return (0); 1251 case TIOCCDTR: 1252 ttydevsw_modem(tp, 0, SER_DTR); 1253 return (0); 1254 case TIOCMSET: { 1255 int bits = *(int *)data; 1256 ttydevsw_modem(tp, 1257 (bits & (TIOCM_DTR | TIOCM_RTS)) >> 1, 1258 ((~bits) & (TIOCM_DTR | TIOCM_RTS)) >> 1); 1259 return (0); 1260 } 1261 case TIOCMBIS: { 1262 int bits = *(int *)data; 1263 ttydevsw_modem(tp, (bits & (TIOCM_DTR | TIOCM_RTS)) >> 1, 0); 1264 return (0); 1265 } 1266 case TIOCMBIC: { 1267 int bits = *(int *)data; 1268 ttydevsw_modem(tp, 0, (bits & (TIOCM_DTR | TIOCM_RTS)) >> 1); 1269 return (0); 1270 } 1271 case TIOCMGET: 1272 *(int *)data = TIOCM_LE + (ttydevsw_modem(tp, 0, 0) << 1); 1273 return (0); 1274 1275 case FIOASYNC: 1276 if (*(int *)data) 1277 tp->t_flags |= TF_ASYNC; 1278 else 1279 tp->t_flags &= ~TF_ASYNC; 1280 return (0); 1281 case FIONBIO: 1282 /* This device supports non-blocking operation. */ 1283 return (0); 1284 case FIONREAD: 1285 *(int *)data = ttyinq_bytescanonicalized(&tp->t_inq); 1286 return (0); 1287 case FIOSETOWN: 1288 if (tp->t_session != NULL && !tty_is_ctty(tp, td->td_proc)) 1289 /* Not allowed to set ownership. */ 1290 return (ENOTTY); 1291 1292 /* Temporarily unlock the TTY to set ownership. */ 1293 tty_unlock(tp); 1294 error = fsetown(*(int *)data, &tp->t_sigio); 1295 tty_lock(tp); 1296 return (error); 1297 case FIOGETOWN: 1298 if (tp->t_session != NULL && !tty_is_ctty(tp, td->td_proc)) 1299 /* Not allowed to set ownership. */ 1300 return (ENOTTY); 1301 1302 /* Get ownership. */ 1303 *(int *)data = fgetown(&tp->t_sigio); 1304 return (0); 1305 case TIOCGETA: 1306 /* Obtain terminal flags through tcgetattr(). */ 1307 bcopy(&tp->t_termios, data, sizeof(struct termios)); 1308 return (0); 1309 case TIOCSETA: 1310 case TIOCSETAW: 1311 case TIOCSETAF: { 1312 struct termios *t = data; 1313 1314 /* 1315 * Who makes up these funny rules? According to POSIX, 1316 * input baud rate is set equal to the output baud rate 1317 * when zero. 1318 */ 1319 if (t->c_ispeed == 0) 1320 t->c_ispeed = t->c_ospeed; 1321 1322 /* Discard any unsupported bits. */ 1323 t->c_iflag &= TTYSUP_IFLAG; 1324 t->c_oflag &= TTYSUP_OFLAG; 1325 t->c_lflag &= TTYSUP_LFLAG; 1326 t->c_cflag &= TTYSUP_CFLAG; 1327 1328 /* Set terminal flags through tcsetattr(). */ 1329 if (cmd == TIOCSETAW || cmd == TIOCSETAF) { 1330 error = tty_drain(tp); 1331 if (error) 1332 return (error); 1333 if (cmd == TIOCSETAF) 1334 tty_flush(tp, FREAD); 1335 } 1336 1337 /* 1338 * Only call param() when the flags really change. 1339 */ 1340 if ((t->c_cflag & CIGNORE) == 0 && 1341 (tp->t_termios.c_cflag != t->c_cflag || 1342 tp->t_termios.c_ispeed != t->c_ispeed || 1343 tp->t_termios.c_ospeed != t->c_ospeed)) { 1344 error = ttydevsw_param(tp, t); 1345 if (error) 1346 return (error); 1347 1348 /* XXX: CLOCAL? */ 1349 1350 tp->t_termios.c_cflag = t->c_cflag & ~CIGNORE; 1351 tp->t_termios.c_ispeed = t->c_ispeed; 1352 tp->t_termios.c_ospeed = t->c_ospeed; 1353 1354 /* Baud rate has changed - update watermarks. */ 1355 tty_watermarks(tp); 1356 } 1357 1358 /* Copy new non-device driver parameters. */ 1359 tp->t_termios.c_iflag = t->c_iflag; 1360 tp->t_termios.c_oflag = t->c_oflag; 1361 tp->t_termios.c_lflag = t->c_lflag; 1362 bcopy(t->c_cc, &tp->t_termios.c_cc, sizeof(t->c_cc)); 1363 1364 ttydisc_optimize(tp); 1365 1366 if ((t->c_lflag & ICANON) == 0) { 1367 /* 1368 * When in non-canonical mode, wake up all 1369 * readers. Canonicalize any partial input. VMIN 1370 * and VTIME could also be adjusted. 1371 */ 1372 ttyinq_canonicalize(&tp->t_inq); 1373 tty_wakeup(tp, FREAD); 1374 } 1375 return (0); 1376 } 1377 case TIOCGETD: 1378 /* For compatibility - we only support TTYDISC. */ 1379 *(int *)data = TTYDISC; 1380 return (0); 1381 case TIOCGPGRP: 1382 if (!tty_is_ctty(tp, td->td_proc)) 1383 return (ENOTTY); 1384 1385 if (tp->t_pgrp != NULL) 1386 *(int *)data = tp->t_pgrp->pg_id; 1387 else 1388 *(int *)data = NO_PID; 1389 return (0); 1390 case TIOCGSID: 1391 if (!tty_is_ctty(tp, td->td_proc)) 1392 return (ENOTTY); 1393 1394 MPASS(tp->t_session); 1395 *(int *)data = tp->t_session->s_sid; 1396 return (0); 1397 case TIOCSCTTY: { 1398 struct proc *p = td->td_proc; 1399 1400 /* XXX: This looks awful. */ 1401 tty_unlock(tp); 1402 sx_xlock(&proctree_lock); 1403 tty_lock(tp); 1404 1405 if (!SESS_LEADER(p)) { 1406 /* Only the session leader may do this. */ 1407 sx_xunlock(&proctree_lock); 1408 return (EPERM); 1409 } 1410 1411 if (tp->t_session != NULL && tp->t_session == p->p_session) { 1412 /* This is already our controlling TTY. */ 1413 sx_xunlock(&proctree_lock); 1414 return (0); 1415 } 1416 1417 if (!SESS_LEADER(p) || p->p_session->s_ttyvp != NULL || 1418 (tp->t_session != NULL && tp->t_session->s_ttyvp != NULL)) { 1419 /* 1420 * There is already a relation between a TTY and 1421 * a session, or the caller is not the session 1422 * leader. 1423 * 1424 * Allow the TTY to be stolen when the vnode is 1425 * NULL, but the reference to the TTY is still 1426 * active. 1427 */ 1428 sx_xunlock(&proctree_lock); 1429 return (EPERM); 1430 } 1431 1432 /* Connect the session to the TTY. */ 1433 tp->t_session = p->p_session; 1434 tp->t_session->s_ttyp = tp; 1435 tp->t_sessioncnt++; 1436 sx_xunlock(&proctree_lock); 1437 1438 /* Assign foreground process group. */ 1439 tp->t_pgrp = p->p_pgrp; 1440 PROC_LOCK(p); 1441 p->p_flag |= P_CONTROLT; 1442 PROC_UNLOCK(p); 1443 1444 return (0); 1445 } 1446 case TIOCSPGRP: { 1447 struct pgrp *pg; 1448 1449 /* 1450 * XXX: Temporarily unlock the TTY to locate the process 1451 * group. This code would be lot nicer if we would ever 1452 * decompose proctree_lock. 1453 */ 1454 tty_unlock(tp); 1455 sx_slock(&proctree_lock); 1456 pg = pgfind(*(int *)data); 1457 if (pg != NULL) 1458 PGRP_UNLOCK(pg); 1459 if (pg == NULL || pg->pg_session != td->td_proc->p_session) { 1460 sx_sunlock(&proctree_lock); 1461 tty_lock(tp); 1462 return (EPERM); 1463 } 1464 tty_lock(tp); 1465 1466 /* 1467 * Determine if this TTY is the controlling TTY after 1468 * relocking the TTY. 1469 */ 1470 if (!tty_is_ctty(tp, td->td_proc)) { 1471 sx_sunlock(&proctree_lock); 1472 return (ENOTTY); 1473 } 1474 tp->t_pgrp = pg; 1475 sx_sunlock(&proctree_lock); 1476 1477 /* Wake up the background process groups. */ 1478 cv_broadcast(&tp->t_bgwait); 1479 return (0); 1480 } 1481 case TIOCFLUSH: { 1482 int flags = *(int *)data; 1483 1484 if (flags == 0) 1485 flags = (FREAD|FWRITE); 1486 else 1487 flags &= (FREAD|FWRITE); 1488 tty_flush(tp, flags); 1489 return (0); 1490 } 1491 case TIOCDRAIN: 1492 /* Drain TTY output. */ 1493 return tty_drain(tp); 1494 case TIOCCONS: 1495 /* Set terminal as console TTY. */ 1496 if (*(int *)data) { 1497 struct nameidata nd; 1498 int vfslocked; 1499 1500 /* 1501 * XXX: TTY won't slip away, but constty would 1502 * really need to be locked! 1503 */ 1504 tty_unlock(tp); 1505 1506 if (constty == tp) { 1507 tty_lock(tp); 1508 return (0); 1509 } 1510 if (constty != NULL) { 1511 tty_lock(tp); 1512 return (EBUSY); 1513 } 1514 /* XXX: allow disconnected constty's to be stolen! */ 1515 1516 /* 1517 * Only allow this to work when the user can 1518 * open /dev/console. 1519 */ 1520 NDINIT(&nd, LOOKUP, FOLLOW|LOCKLEAF|MPSAFE, 1521 UIO_SYSSPACE, "/dev/console", td); 1522 if ((error = namei(&nd)) != 0) { 1523 tty_lock(tp); 1524 return (error); 1525 } 1526 vfslocked = NDHASGIANT(&nd); 1527 NDFREE(&nd, NDF_ONLY_PNBUF); 1528 1529 error = VOP_ACCESS(nd.ni_vp, VREAD, td->td_ucred, td); 1530 vput(nd.ni_vp); 1531 VFS_UNLOCK_GIANT(vfslocked); 1532 if (error) { 1533 tty_lock(tp); 1534 return (error); 1535 } 1536 1537 constty_set(tp); 1538 tty_lock(tp); 1539 } else if (constty == tp) { 1540 constty_clear(); 1541 } 1542 return (0); 1543 case TIOCGWINSZ: 1544 /* Obtain window size. */ 1545 bcopy(&tp->t_winsize, data, sizeof(struct winsize)); 1546 return (0); 1547 case TIOCSWINSZ: 1548 /* Set window size. */ 1549 if (bcmp(&tp->t_winsize, data, sizeof(struct winsize)) == 0) 1550 return (0); 1551 bcopy(data, &tp->t_winsize, sizeof(struct winsize)); 1552 tty_signal_pgrp(tp, SIGWINCH); 1553 return (0); 1554 case TIOCEXCL: 1555 tp->t_flags |= TF_EXCLUDE; 1556 return (0); 1557 case TIOCNXCL: 1558 tp->t_flags &= ~TF_EXCLUDE; 1559 return (0); 1560 case TIOCOUTQ: 1561 *(unsigned int *)data = ttyoutq_bytesused(&tp->t_outq); 1562 return (0); 1563 case TIOCSTOP: 1564 tp->t_flags |= TF_STOPPED; 1565 return (0); 1566 case TIOCSTART: 1567 tp->t_flags &= ~TF_STOPPED; 1568 ttydevsw_outwakeup(tp); 1569 return (0); 1570 case TIOCSTAT: 1571 tty_info(tp); 1572 return (0); 1573 } 1574 1575#ifdef COMPAT_43TTY 1576 return tty_ioctl_compat(tp, cmd, data, td); 1577#else /* !COMPAT_43TTY */ 1578 return (ENOIOCTL); 1579#endif /* COMPAT_43TTY */ 1580} 1581 1582int 1583tty_ioctl(struct tty *tp, u_long cmd, void *data, struct thread *td) 1584{ 1585 int error; 1586 1587 tty_lock_assert(tp, MA_OWNED); 1588 1589 if (tty_gone(tp)) 1590 return (ENXIO); 1591 1592 error = ttydevsw_ioctl(tp, cmd, data, td); 1593 if (error == ENOIOCTL) 1594 error = tty_generic_ioctl(tp, cmd, data, td); 1595 1596 return (error); 1597} 1598 1599dev_t 1600tty_udev(struct tty *tp) 1601{ 1602 if (tp->t_dev) 1603 return dev2udev(tp->t_dev); 1604 else 1605 return NODEV; 1606} 1607 1608int 1609tty_checkoutq(struct tty *tp) 1610{ 1611 1612 /* 256 bytes should be enough to print a log message. */ 1613 return (ttyoutq_bytesleft(&tp->t_outq) >= 256); 1614} 1615 1616void 1617tty_hiwat_in_block(struct tty *tp) 1618{ 1619 1620 if ((tp->t_flags & TF_HIWAT_IN) == 0 && 1621 tp->t_termios.c_iflag & IXOFF && 1622 tp->t_termios.c_cc[VSTOP] != _POSIX_VDISABLE) { 1623 /* 1624 * Input flow control. Only enter the high watermark when we 1625 * can successfully store the VSTOP character. 1626 */ 1627 if (ttyoutq_write_nofrag(&tp->t_outq, 1628 &tp->t_termios.c_cc[VSTOP], 1) == 0) 1629 tp->t_flags |= TF_HIWAT_IN; 1630 } else { 1631 /* No input flow control. */ 1632 tp->t_flags |= TF_HIWAT_IN; 1633 } 1634} 1635 1636void 1637tty_hiwat_in_unblock(struct tty *tp) 1638{ 1639 1640 if (tp->t_flags & TF_HIWAT_IN && 1641 tp->t_termios.c_iflag & IXOFF && 1642 tp->t_termios.c_cc[VSTART] != _POSIX_VDISABLE) { 1643 /* 1644 * Input flow control. Only leave the high watermark when we 1645 * can successfully store the VSTART character. 1646 */ 1647 if (ttyoutq_write_nofrag(&tp->t_outq, 1648 &tp->t_termios.c_cc[VSTART], 1) == 0) 1649 tp->t_flags &= ~TF_HIWAT_IN; 1650 } else { 1651 /* No input flow control. */ 1652 tp->t_flags &= ~TF_HIWAT_IN; 1653 } 1654 1655 if (!tty_gone(tp)) 1656 ttydevsw_inwakeup(tp); 1657} 1658 1659#include "opt_ddb.h" 1660#ifdef DDB 1661#include <ddb/ddb.h> 1662 1663static struct { 1664 int flag; 1665 char val; 1666} ttystates[] = { 1667#if 0 1668 { TF_NOPREFIX, 'N' }, 1669#endif 1670 { TF_INITLOCK, 'I' }, 1671 { TF_CALLOUT, 'C' }, 1672 1673 /* Keep these together -> 'Oi' and 'Oo'. */ 1674 { TF_OPENED, 'O' }, 1675 { TF_OPENED_IN, 'i' }, 1676 { TF_OPENED_OUT,'o' }, 1677 1678 { TF_GONE, 'G' }, 1679 { TF_OPENCLOSE, 'B' }, 1680 { TF_ASYNC, 'Y' }, 1681 { TF_LITERAL, 'L' }, 1682 1683 /* Keep these together -> 'Hi' and 'Ho'. */ 1684 { TF_HIWAT, 'H' }, 1685 { TF_HIWAT_IN, 'i' }, 1686 { TF_HIWAT_OUT, 'o' }, 1687 1688 { TF_STOPPED, 'S' }, 1689 { TF_EXCLUDE, 'X' }, 1690 { TF_BYPASS, 'l' }, 1691 { TF_ZOMBIE, 'Z' }, 1692 1693 { 0, '\0' }, 1694}; 1695 1696/* DDB command to show TTY statistics. */ 1697DB_SHOW_COMMAND(ttys, db_show_ttys) 1698{ 1699 struct tty *tp; 1700 size_t isiz, osiz; 1701 int i, j; 1702 1703 /* Make the output look like `pstat -t'. */ 1704 db_printf(" LINE INQ CAN LIN LOW OUTQ USE LOW " 1705 "COL SESS PGID STATE\n"); 1706 1707 TAILQ_FOREACH(tp, &tty_list, t_list) { 1708 isiz = tp->t_inq.ti_nblocks * TTYINQ_DATASIZE; 1709 osiz = tp->t_outq.to_nblocks * TTYOUTQ_DATASIZE; 1710 1711 db_printf("%10s %5zu %4u %4u %4zu %5zu %4u %4zu %5u %5d %5d ", 1712 tty_devname(tp), 1713 isiz, 1714 tp->t_inq.ti_linestart - tp->t_inq.ti_begin, 1715 tp->t_inq.ti_end - tp->t_inq.ti_linestart, 1716 isiz - tp->t_inlow, 1717 osiz, 1718 tp->t_outq.to_end - tp->t_outq.to_begin, 1719 osiz - tp->t_outlow, 1720 tp->t_column, 1721 tp->t_session ? tp->t_session->s_sid : 0, 1722 tp->t_pgrp ? tp->t_pgrp->pg_id : 0); 1723 1724 /* Flag bits. */ 1725 for (i = j = 0; ttystates[i].flag; i++) 1726 if (tp->t_flags & ttystates[i].flag) { 1727 db_printf("%c", ttystates[i].val); 1728 j++; 1729 } 1730 if (j == 0) 1731 db_printf("-"); 1732 db_printf("\n"); 1733 } 1734} 1735#endif /* DDB */ 1736