tty.c revision 182764
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 182764 2008-09-04 16:39:02Z 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_defpktnotify(struct tty *tp, char event) 820{ 821} 822 823static void 824ttydevsw_deffree(void *softc) 825{ 826 827 panic("Terminal device freed without a free-handler"); 828} 829 830/* 831 * TTY allocation and deallocation. TTY devices can be deallocated when 832 * the driver doesn't use it anymore, when the TTY isn't a session's 833 * controlling TTY and when the device node isn't opened through devfs. 834 */ 835 836struct tty * 837tty_alloc(struct ttydevsw *tsw, void *sc, struct mtx *mutex) 838{ 839 struct tty *tp; 840 841 /* Make sure the driver defines all routines. */ 842#define PATCH_FUNC(x) do { \ 843 if (tsw->tsw_ ## x == NULL) \ 844 tsw->tsw_ ## x = ttydevsw_def ## x; \ 845} while (0) 846 PATCH_FUNC(open); 847 PATCH_FUNC(close); 848 PATCH_FUNC(outwakeup); 849 PATCH_FUNC(inwakeup); 850 PATCH_FUNC(ioctl); 851 PATCH_FUNC(param); 852 PATCH_FUNC(modem); 853 PATCH_FUNC(mmap); 854 PATCH_FUNC(pktnotify); 855 PATCH_FUNC(free); 856#undef PATCH_FUNC 857 858 tp = malloc(sizeof(struct tty), M_TTY, M_WAITOK|M_ZERO); 859 tp->t_devsw = tsw; 860 tp->t_softc = sc; 861 tp->t_flags = tsw->tsw_flags; 862 863 tty_init_termios(tp); 864 865 cv_init(&tp->t_inwait, "tty input"); 866 cv_init(&tp->t_outwait, "tty output"); 867 cv_init(&tp->t_bgwait, "tty background"); 868 cv_init(&tp->t_dcdwait, "tty dcd"); 869 870 ttyinq_init(&tp->t_inq); 871 ttyoutq_init(&tp->t_outq); 872 873 /* Allow drivers to use a custom mutex to lock the TTY. */ 874 if (mutex != NULL) { 875 tp->t_mtx = mutex; 876 } else { 877 tp->t_mtx = &tp->t_mtxobj; 878 mtx_init(&tp->t_mtxobj, "tty lock", NULL, MTX_DEF); 879 } 880 881 knlist_init(&tp->t_inpoll.si_note, tp->t_mtx, NULL, NULL, NULL); 882 knlist_init(&tp->t_outpoll.si_note, tp->t_mtx, NULL, NULL, NULL); 883 884 sx_xlock(&tty_list_sx); 885 TAILQ_INSERT_TAIL(&tty_list, tp, t_list); 886 tty_list_count++; 887 sx_xunlock(&tty_list_sx); 888 889 return (tp); 890} 891 892static void 893tty_dealloc(void *arg) 894{ 895 struct tty *tp = arg; 896 897 sx_xlock(&tty_list_sx); 898 TAILQ_REMOVE(&tty_list, tp, t_list); 899 tty_list_count--; 900 sx_xunlock(&tty_list_sx); 901 902 /* Make sure we haven't leaked buffers. */ 903 MPASS(ttyinq_getsize(&tp->t_inq) == 0); 904 MPASS(ttyoutq_getsize(&tp->t_outq) == 0); 905 906 knlist_destroy(&tp->t_inpoll.si_note); 907 knlist_destroy(&tp->t_outpoll.si_note); 908 909 cv_destroy(&tp->t_inwait); 910 cv_destroy(&tp->t_outwait); 911 cv_destroy(&tp->t_bgwait); 912 cv_destroy(&tp->t_dcdwait); 913 914 if (tp->t_mtx == &tp->t_mtxobj) 915 mtx_destroy(&tp->t_mtxobj); 916 ttydevsw_free(tp); 917 free(tp, M_TTY); 918} 919 920static void 921tty_rel_free(struct tty *tp) 922{ 923 struct cdev *dev; 924 925 tty_lock_assert(tp, MA_OWNED); 926 927 if (tp->t_sessioncnt != 0 || 928 (tp->t_flags & (TF_GONE|TF_OPENED)) != TF_GONE) { 929 /* TTY is still in use. */ 930 tty_unlock(tp); 931 return; 932 } 933 934 /* TTY can be deallocated. */ 935 dev = tp->t_dev; 936 tp->t_dev = NULL; 937 tty_unlock(tp); 938 939 destroy_dev_sched_cb(dev, tty_dealloc, tp); 940} 941 942void 943tty_rel_pgrp(struct tty *tp, struct pgrp *pg) 944{ 945 tty_lock_assert(tp, MA_OWNED); 946 947 if (tp->t_pgrp == pg) 948 tp->t_pgrp = NULL; 949} 950 951void 952tty_rel_sess(struct tty *tp, struct session *sess) 953{ 954 MPASS(tp->t_sessioncnt > 0); 955 956 /* Current session has left. */ 957 if (tp->t_session == sess) { 958 tp->t_session = NULL; 959 MPASS(tp->t_pgrp == NULL); 960 } 961 tp->t_sessioncnt--; 962 tty_rel_free(tp); 963} 964 965void 966tty_rel_gone(struct tty *tp) 967{ 968 MPASS(!tty_gone(tp)); 969 970 /* Simulate carrier removal. */ 971 ttydisc_modem(tp, 0); 972 973 /* Wake up misc. blocked threads. */ 974 cv_broadcast(&tp->t_bgwait); 975 cv_broadcast(&tp->t_dcdwait); 976 977 tp->t_flags |= TF_GONE; 978 tty_rel_free(tp); 979} 980 981/* 982 * Exposing information about current TTY's through sysctl 983 */ 984 985static void 986tty_to_xtty(struct tty *tp, struct xtty *xt) 987{ 988 tty_lock_assert(tp, MA_OWNED); 989 990 xt->xt_size = sizeof(struct xtty); 991 xt->xt_insize = ttyinq_getsize(&tp->t_inq); 992 xt->xt_incc = ttyinq_bytescanonicalized(&tp->t_inq); 993 xt->xt_inlc = ttyinq_bytesline(&tp->t_inq); 994 xt->xt_inlow = tp->t_inlow; 995 xt->xt_outsize = ttyoutq_getsize(&tp->t_outq); 996 xt->xt_outcc = ttyoutq_bytesused(&tp->t_outq); 997 xt->xt_outlow = tp->t_outlow; 998 xt->xt_column = tp->t_column; 999 xt->xt_pgid = tp->t_pgrp ? tp->t_pgrp->pg_id : 0; 1000 xt->xt_sid = tp->t_session ? tp->t_session->s_sid : 0; 1001 xt->xt_flags = tp->t_flags; 1002 xt->xt_dev = tp->t_dev ? dev2udev(tp->t_dev) : NODEV; 1003} 1004 1005static int 1006sysctl_kern_ttys(SYSCTL_HANDLER_ARGS) 1007{ 1008 unsigned long lsize; 1009 struct xtty *xtlist, *xt; 1010 struct tty *tp; 1011 int error; 1012 1013 sx_slock(&tty_list_sx); 1014 lsize = tty_list_count * sizeof(struct xtty); 1015 if (lsize == 0) { 1016 sx_sunlock(&tty_list_sx); 1017 return (0); 1018 } 1019 1020 xtlist = xt = malloc(lsize, M_TEMP, M_WAITOK); 1021 1022 TAILQ_FOREACH(tp, &tty_list, t_list) { 1023 tty_lock(tp); 1024 tty_to_xtty(tp, xt); 1025 tty_unlock(tp); 1026 xt++; 1027 } 1028 sx_sunlock(&tty_list_sx); 1029 1030 error = SYSCTL_OUT(req, xtlist, lsize); 1031 free(xtlist, M_TEMP); 1032 return (error); 1033} 1034 1035SYSCTL_PROC(_kern, OID_AUTO, ttys, CTLTYPE_OPAQUE|CTLFLAG_RD, 1036 0, 0, sysctl_kern_ttys, "S,xtty", "List of TTYs"); 1037 1038/* 1039 * Device node creation. Device has been set up, now we can expose it to 1040 * the user. 1041 */ 1042 1043void 1044tty_makedev(struct tty *tp, struct ucred *cred, const char *fmt, ...) 1045{ 1046 va_list ap; 1047 struct cdev *dev; 1048 const char *prefix = "tty"; 1049 char name[SPECNAMELEN - 3]; /* for "tty" and "cua". */ 1050 uid_t uid; 1051 gid_t gid; 1052 mode_t mode; 1053 1054 /* Remove "tty" prefix from devices like PTY's. */ 1055 if (tp->t_flags & TF_NOPREFIX) 1056 prefix = ""; 1057 1058 va_start(ap, fmt); 1059 vsnrprintf(name, sizeof name, 32, fmt, ap); 1060 va_end(ap); 1061 1062 if (cred == NULL) { 1063 /* System device. */ 1064 uid = UID_ROOT; 1065 gid = GID_WHEEL; 1066 mode = S_IRUSR|S_IWUSR; 1067 } else { 1068 /* User device. */ 1069 uid = cred->cr_ruid; 1070 gid = GID_TTY; 1071 mode = S_IRUSR|S_IWUSR|S_IWGRP; 1072 } 1073 1074 /* Master call-in device. */ 1075 dev = make_dev_cred(&ttydev_cdevsw, 0, cred, 1076 uid, gid, mode, "%s%s", prefix, name); 1077 dev->si_drv1 = tp; 1078 tp->t_dev = dev; 1079 1080 /* Slave call-in devices. */ 1081 if (tp->t_flags & TF_INITLOCK) { 1082 dev = make_dev_cred(&ttyil_cdevsw, 0, cred, 1083 uid, gid, mode, "%s%s.init", prefix, name); 1084 dev_depends(tp->t_dev, dev); 1085 dev->si_drv1 = tp; 1086 dev->si_drv2 = &tp->t_termios_init_in; 1087 1088 dev = make_dev_cred(&ttyil_cdevsw, 0, cred, 1089 uid, gid, mode, "%s%s.lock", prefix, name); 1090 dev_depends(tp->t_dev, dev); 1091 dev->si_drv1 = tp; 1092 dev->si_drv2 = &tp->t_termios_lock_in; 1093 } 1094 1095 /* Call-out devices. */ 1096 if (tp->t_flags & TF_CALLOUT) { 1097 dev = make_dev_cred(&ttydev_cdevsw, 0, cred, 1098 UID_UUCP, GID_DIALER, 0660, "cua%s", name); 1099 dev_depends(tp->t_dev, dev); 1100 dev->si_drv1 = tp; 1101 1102 /* Slave call-out devices. */ 1103 if (tp->t_flags & TF_INITLOCK) { 1104 dev = make_dev_cred(&ttyil_cdevsw, 0, cred, 1105 UID_UUCP, GID_DIALER, 0660, "cua%s.init", name); 1106 dev_depends(tp->t_dev, dev); 1107 dev->si_drv1 = tp; 1108 dev->si_drv2 = &tp->t_termios_init_out; 1109 1110 dev = make_dev_cred(&ttyil_cdevsw, 0, cred, 1111 UID_UUCP, GID_DIALER, 0660, "cua%s.lock", name); 1112 dev_depends(tp->t_dev, dev); 1113 dev->si_drv1 = tp; 1114 dev->si_drv2 = &tp->t_termios_lock_out; 1115 } 1116 } 1117} 1118 1119/* 1120 * Signalling processes. 1121 */ 1122 1123void 1124tty_signal_sessleader(struct tty *tp, int sig) 1125{ 1126 struct proc *p; 1127 1128 tty_lock_assert(tp, MA_OWNED); 1129 MPASS(sig >= 1 && sig < NSIG); 1130 1131 /* Make signals start output again. */ 1132 tp->t_flags &= ~TF_STOPPED; 1133 1134 if (tp->t_session != NULL && tp->t_session->s_leader != NULL) { 1135 p = tp->t_session->s_leader; 1136 PROC_LOCK(p); 1137 psignal(p, sig); 1138 PROC_UNLOCK(p); 1139 } 1140} 1141 1142void 1143tty_signal_pgrp(struct tty *tp, int sig) 1144{ 1145 tty_lock_assert(tp, MA_OWNED); 1146 MPASS(sig >= 1 && sig < NSIG); 1147 1148 /* Make signals start output again. */ 1149 tp->t_flags &= ~TF_STOPPED; 1150 1151 if (sig == SIGINFO && !(tp->t_termios.c_lflag & NOKERNINFO)) 1152 tty_info(tp); 1153 if (tp->t_pgrp != NULL) { 1154 PGRP_LOCK(tp->t_pgrp); 1155 pgsignal(tp->t_pgrp, sig, 1); 1156 PGRP_UNLOCK(tp->t_pgrp); 1157 } 1158} 1159 1160void 1161tty_wakeup(struct tty *tp, int flags) 1162{ 1163 if (tp->t_flags & TF_ASYNC && tp->t_sigio != NULL) 1164 pgsigio(&tp->t_sigio, SIGIO, (tp->t_session != NULL)); 1165 1166 if (flags & FWRITE) { 1167 cv_broadcast(&tp->t_outwait); 1168 selwakeup(&tp->t_outpoll); 1169 KNOTE_LOCKED(&tp->t_outpoll.si_note, 0); 1170 } 1171 if (flags & FREAD) { 1172 cv_broadcast(&tp->t_inwait); 1173 selwakeup(&tp->t_inpoll); 1174 KNOTE_LOCKED(&tp->t_inpoll.si_note, 0); 1175 } 1176} 1177 1178int 1179tty_wait(struct tty *tp, struct cv *cv) 1180{ 1181 int error; 1182 int revokecnt = tp->t_revokecnt; 1183 1184#if 0 1185 /* XXX: /dev/console also picks up Giant. */ 1186 tty_lock_assert(tp, MA_OWNED|MA_NOTRECURSED); 1187#endif 1188 tty_lock_assert(tp, MA_OWNED); 1189 1190 error = cv_wait_sig(cv, tp->t_mtx); 1191 1192 /* Restart the system call when we may have been revoked. */ 1193 if (tp->t_revokecnt != revokecnt) 1194 return (ERESTART); 1195 1196 /* Bail out when the device slipped away. */ 1197 if (tty_gone(tp)) 1198 return (ENXIO); 1199 1200 return (error); 1201} 1202 1203int 1204tty_timedwait(struct tty *tp, struct cv *cv, int hz) 1205{ 1206 int error; 1207 int revokecnt = tp->t_revokecnt; 1208 1209#if 0 1210 /* XXX: /dev/console also picks up Giant. */ 1211 tty_lock_assert(tp, MA_OWNED|MA_NOTRECURSED); 1212#endif 1213 tty_lock_assert(tp, MA_OWNED); 1214 1215 error = cv_timedwait_sig(cv, tp->t_mtx, hz); 1216 1217 /* Restart the system call when we may have been revoked. */ 1218 if (tp->t_revokecnt != revokecnt) 1219 return (ERESTART); 1220 1221 /* Bail out when the device slipped away. */ 1222 if (tty_gone(tp)) 1223 return (ENXIO); 1224 1225 return (error); 1226} 1227 1228void 1229tty_flush(struct tty *tp, int flags) 1230{ 1231 if (flags & FWRITE) { 1232 tp->t_flags &= ~TF_HIWAT_OUT; 1233 ttyoutq_flush(&tp->t_outq); 1234 tty_wakeup(tp, FWRITE); 1235 ttydevsw_pktnotify(tp, TIOCPKT_FLUSHWRITE); 1236 } 1237 if (flags & FREAD) { 1238 tty_hiwat_in_unblock(tp); 1239 ttyinq_flush(&tp->t_inq); 1240 ttydevsw_inwakeup(tp); 1241 ttydevsw_pktnotify(tp, TIOCPKT_FLUSHREAD); 1242 } 1243} 1244 1245static int 1246tty_generic_ioctl(struct tty *tp, u_long cmd, void *data, struct thread *td) 1247{ 1248 int error; 1249 1250 switch (cmd) { 1251 /* 1252 * Modem commands. 1253 * The SER_* and TIOCM_* flags are the same, but one bit 1254 * shifted. I don't know why. 1255 */ 1256 case TIOCSDTR: 1257 ttydevsw_modem(tp, SER_DTR, 0); 1258 return (0); 1259 case TIOCCDTR: 1260 ttydevsw_modem(tp, 0, SER_DTR); 1261 return (0); 1262 case TIOCMSET: { 1263 int bits = *(int *)data; 1264 ttydevsw_modem(tp, 1265 (bits & (TIOCM_DTR | TIOCM_RTS)) >> 1, 1266 ((~bits) & (TIOCM_DTR | TIOCM_RTS)) >> 1); 1267 return (0); 1268 } 1269 case TIOCMBIS: { 1270 int bits = *(int *)data; 1271 ttydevsw_modem(tp, (bits & (TIOCM_DTR | TIOCM_RTS)) >> 1, 0); 1272 return (0); 1273 } 1274 case TIOCMBIC: { 1275 int bits = *(int *)data; 1276 ttydevsw_modem(tp, 0, (bits & (TIOCM_DTR | TIOCM_RTS)) >> 1); 1277 return (0); 1278 } 1279 case TIOCMGET: 1280 *(int *)data = TIOCM_LE + (ttydevsw_modem(tp, 0, 0) << 1); 1281 return (0); 1282 1283 case FIOASYNC: 1284 if (*(int *)data) 1285 tp->t_flags |= TF_ASYNC; 1286 else 1287 tp->t_flags &= ~TF_ASYNC; 1288 return (0); 1289 case FIONBIO: 1290 /* This device supports non-blocking operation. */ 1291 return (0); 1292 case FIONREAD: 1293 *(int *)data = ttyinq_bytescanonicalized(&tp->t_inq); 1294 return (0); 1295 case FIOSETOWN: 1296 if (tp->t_session != NULL && !tty_is_ctty(tp, td->td_proc)) 1297 /* Not allowed to set ownership. */ 1298 return (ENOTTY); 1299 1300 /* Temporarily unlock the TTY to set ownership. */ 1301 tty_unlock(tp); 1302 error = fsetown(*(int *)data, &tp->t_sigio); 1303 tty_lock(tp); 1304 return (error); 1305 case FIOGETOWN: 1306 if (tp->t_session != NULL && !tty_is_ctty(tp, td->td_proc)) 1307 /* Not allowed to set ownership. */ 1308 return (ENOTTY); 1309 1310 /* Get ownership. */ 1311 *(int *)data = fgetown(&tp->t_sigio); 1312 return (0); 1313 case TIOCGETA: 1314 /* Obtain terminal flags through tcgetattr(). */ 1315 bcopy(&tp->t_termios, data, sizeof(struct termios)); 1316 return (0); 1317 case TIOCSETA: 1318 case TIOCSETAW: 1319 case TIOCSETAF: { 1320 struct termios *t = data; 1321 1322 /* 1323 * Who makes up these funny rules? According to POSIX, 1324 * input baud rate is set equal to the output baud rate 1325 * when zero. 1326 */ 1327 if (t->c_ispeed == 0) 1328 t->c_ispeed = t->c_ospeed; 1329 1330 /* Discard any unsupported bits. */ 1331 t->c_iflag &= TTYSUP_IFLAG; 1332 t->c_oflag &= TTYSUP_OFLAG; 1333 t->c_lflag &= TTYSUP_LFLAG; 1334 t->c_cflag &= TTYSUP_CFLAG; 1335 1336 /* Set terminal flags through tcsetattr(). */ 1337 if (cmd == TIOCSETAW || cmd == TIOCSETAF) { 1338 error = tty_drain(tp); 1339 if (error) 1340 return (error); 1341 if (cmd == TIOCSETAF) 1342 tty_flush(tp, FREAD); 1343 } 1344 1345 /* 1346 * Only call param() when the flags really change. 1347 */ 1348 if ((t->c_cflag & CIGNORE) == 0 && 1349 (tp->t_termios.c_cflag != t->c_cflag || 1350 tp->t_termios.c_ispeed != t->c_ispeed || 1351 tp->t_termios.c_ospeed != t->c_ospeed)) { 1352 error = ttydevsw_param(tp, t); 1353 if (error) 1354 return (error); 1355 1356 /* XXX: CLOCAL? */ 1357 1358 tp->t_termios.c_cflag = t->c_cflag & ~CIGNORE; 1359 tp->t_termios.c_ispeed = t->c_ispeed; 1360 tp->t_termios.c_ospeed = t->c_ospeed; 1361 1362 /* Baud rate has changed - update watermarks. */ 1363 tty_watermarks(tp); 1364 } 1365 1366 /* Copy new non-device driver parameters. */ 1367 tp->t_termios.c_iflag = t->c_iflag; 1368 tp->t_termios.c_oflag = t->c_oflag; 1369 tp->t_termios.c_lflag = t->c_lflag; 1370 bcopy(t->c_cc, &tp->t_termios.c_cc, sizeof(t->c_cc)); 1371 1372 ttydisc_optimize(tp); 1373 1374 if ((t->c_lflag & ICANON) == 0) { 1375 /* 1376 * When in non-canonical mode, wake up all 1377 * readers. Canonicalize any partial input. VMIN 1378 * and VTIME could also be adjusted. 1379 */ 1380 ttyinq_canonicalize(&tp->t_inq); 1381 tty_wakeup(tp, FREAD); 1382 } 1383 1384 /* 1385 * For packet mode: notify the PTY consumer that VSTOP 1386 * and VSTART may have been changed. 1387 */ 1388 if (tp->t_termios.c_iflag & IXON && 1389 tp->t_termios.c_cc[VSTOP] == CTRL('S') && 1390 tp->t_termios.c_cc[VSTART] == CTRL('Q')) 1391 ttydevsw_pktnotify(tp, TIOCPKT_DOSTOP); 1392 else 1393 ttydevsw_pktnotify(tp, TIOCPKT_NOSTOP); 1394 return (0); 1395 } 1396 case TIOCGETD: 1397 /* For compatibility - we only support TTYDISC. */ 1398 *(int *)data = TTYDISC; 1399 return (0); 1400 case TIOCGPGRP: 1401 if (!tty_is_ctty(tp, td->td_proc)) 1402 return (ENOTTY); 1403 1404 if (tp->t_pgrp != NULL) 1405 *(int *)data = tp->t_pgrp->pg_id; 1406 else 1407 *(int *)data = NO_PID; 1408 return (0); 1409 case TIOCGSID: 1410 if (!tty_is_ctty(tp, td->td_proc)) 1411 return (ENOTTY); 1412 1413 MPASS(tp->t_session); 1414 *(int *)data = tp->t_session->s_sid; 1415 return (0); 1416 case TIOCSCTTY: { 1417 struct proc *p = td->td_proc; 1418 1419 /* XXX: This looks awful. */ 1420 tty_unlock(tp); 1421 sx_xlock(&proctree_lock); 1422 tty_lock(tp); 1423 1424 if (!SESS_LEADER(p)) { 1425 /* Only the session leader may do this. */ 1426 sx_xunlock(&proctree_lock); 1427 return (EPERM); 1428 } 1429 1430 if (tp->t_session != NULL && tp->t_session == p->p_session) { 1431 /* This is already our controlling TTY. */ 1432 sx_xunlock(&proctree_lock); 1433 return (0); 1434 } 1435 1436 if (!SESS_LEADER(p) || p->p_session->s_ttyvp != NULL || 1437 (tp->t_session != NULL && tp->t_session->s_ttyvp != NULL)) { 1438 /* 1439 * There is already a relation between a TTY and 1440 * a session, or the caller is not the session 1441 * leader. 1442 * 1443 * Allow the TTY to be stolen when the vnode is 1444 * NULL, but the reference to the TTY is still 1445 * active. 1446 */ 1447 sx_xunlock(&proctree_lock); 1448 return (EPERM); 1449 } 1450 1451 /* Connect the session to the TTY. */ 1452 tp->t_session = p->p_session; 1453 tp->t_session->s_ttyp = tp; 1454 tp->t_sessioncnt++; 1455 sx_xunlock(&proctree_lock); 1456 1457 /* Assign foreground process group. */ 1458 tp->t_pgrp = p->p_pgrp; 1459 PROC_LOCK(p); 1460 p->p_flag |= P_CONTROLT; 1461 PROC_UNLOCK(p); 1462 1463 return (0); 1464 } 1465 case TIOCSPGRP: { 1466 struct pgrp *pg; 1467 1468 /* 1469 * XXX: Temporarily unlock the TTY to locate the process 1470 * group. This code would be lot nicer if we would ever 1471 * decompose proctree_lock. 1472 */ 1473 tty_unlock(tp); 1474 sx_slock(&proctree_lock); 1475 pg = pgfind(*(int *)data); 1476 if (pg != NULL) 1477 PGRP_UNLOCK(pg); 1478 if (pg == NULL || pg->pg_session != td->td_proc->p_session) { 1479 sx_sunlock(&proctree_lock); 1480 tty_lock(tp); 1481 return (EPERM); 1482 } 1483 tty_lock(tp); 1484 1485 /* 1486 * Determine if this TTY is the controlling TTY after 1487 * relocking the TTY. 1488 */ 1489 if (!tty_is_ctty(tp, td->td_proc)) { 1490 sx_sunlock(&proctree_lock); 1491 return (ENOTTY); 1492 } 1493 tp->t_pgrp = pg; 1494 sx_sunlock(&proctree_lock); 1495 1496 /* Wake up the background process groups. */ 1497 cv_broadcast(&tp->t_bgwait); 1498 return (0); 1499 } 1500 case TIOCFLUSH: { 1501 int flags = *(int *)data; 1502 1503 if (flags == 0) 1504 flags = (FREAD|FWRITE); 1505 else 1506 flags &= (FREAD|FWRITE); 1507 tty_flush(tp, flags); 1508 return (0); 1509 } 1510 case TIOCDRAIN: 1511 /* Drain TTY output. */ 1512 return tty_drain(tp); 1513 case TIOCCONS: 1514 /* Set terminal as console TTY. */ 1515 if (*(int *)data) { 1516 struct nameidata nd; 1517 int vfslocked; 1518 1519 /* 1520 * XXX: TTY won't slip away, but constty would 1521 * really need to be locked! 1522 */ 1523 tty_unlock(tp); 1524 1525 if (constty == tp) { 1526 tty_lock(tp); 1527 return (0); 1528 } 1529 if (constty != NULL) { 1530 tty_lock(tp); 1531 return (EBUSY); 1532 } 1533 /* XXX: allow disconnected constty's to be stolen! */ 1534 1535 /* 1536 * Only allow this to work when the user can 1537 * open /dev/console. 1538 */ 1539 NDINIT(&nd, LOOKUP, FOLLOW|LOCKLEAF|MPSAFE, 1540 UIO_SYSSPACE, "/dev/console", td); 1541 if ((error = namei(&nd)) != 0) { 1542 tty_lock(tp); 1543 return (error); 1544 } 1545 vfslocked = NDHASGIANT(&nd); 1546 NDFREE(&nd, NDF_ONLY_PNBUF); 1547 1548 error = VOP_ACCESS(nd.ni_vp, VREAD, td->td_ucred, td); 1549 vput(nd.ni_vp); 1550 VFS_UNLOCK_GIANT(vfslocked); 1551 if (error) { 1552 tty_lock(tp); 1553 return (error); 1554 } 1555 1556 constty_set(tp); 1557 tty_lock(tp); 1558 } else if (constty == tp) { 1559 constty_clear(); 1560 } 1561 return (0); 1562 case TIOCGWINSZ: 1563 /* Obtain window size. */ 1564 bcopy(&tp->t_winsize, data, sizeof(struct winsize)); 1565 return (0); 1566 case TIOCSWINSZ: 1567 /* Set window size. */ 1568 if (bcmp(&tp->t_winsize, data, sizeof(struct winsize)) == 0) 1569 return (0); 1570 bcopy(data, &tp->t_winsize, sizeof(struct winsize)); 1571 tty_signal_pgrp(tp, SIGWINCH); 1572 return (0); 1573 case TIOCEXCL: 1574 tp->t_flags |= TF_EXCLUDE; 1575 return (0); 1576 case TIOCNXCL: 1577 tp->t_flags &= ~TF_EXCLUDE; 1578 return (0); 1579 case TIOCOUTQ: 1580 *(unsigned int *)data = ttyoutq_bytesused(&tp->t_outq); 1581 return (0); 1582 case TIOCSTOP: 1583 tp->t_flags |= TF_STOPPED; 1584 ttydevsw_pktnotify(tp, TIOCPKT_STOP); 1585 return (0); 1586 case TIOCSTART: 1587 tp->t_flags &= ~TF_STOPPED; 1588 ttydevsw_outwakeup(tp); 1589 ttydevsw_pktnotify(tp, TIOCPKT_START); 1590 return (0); 1591 case TIOCSTAT: 1592 tty_info(tp); 1593 return (0); 1594 } 1595 1596#ifdef COMPAT_43TTY 1597 return tty_ioctl_compat(tp, cmd, data, td); 1598#else /* !COMPAT_43TTY */ 1599 return (ENOIOCTL); 1600#endif /* COMPAT_43TTY */ 1601} 1602 1603int 1604tty_ioctl(struct tty *tp, u_long cmd, void *data, struct thread *td) 1605{ 1606 int error; 1607 1608 tty_lock_assert(tp, MA_OWNED); 1609 1610 if (tty_gone(tp)) 1611 return (ENXIO); 1612 1613 error = ttydevsw_ioctl(tp, cmd, data, td); 1614 if (error == ENOIOCTL) 1615 error = tty_generic_ioctl(tp, cmd, data, td); 1616 1617 return (error); 1618} 1619 1620dev_t 1621tty_udev(struct tty *tp) 1622{ 1623 if (tp->t_dev) 1624 return dev2udev(tp->t_dev); 1625 else 1626 return NODEV; 1627} 1628 1629int 1630tty_checkoutq(struct tty *tp) 1631{ 1632 1633 /* 256 bytes should be enough to print a log message. */ 1634 return (ttyoutq_bytesleft(&tp->t_outq) >= 256); 1635} 1636 1637void 1638tty_hiwat_in_block(struct tty *tp) 1639{ 1640 1641 if ((tp->t_flags & TF_HIWAT_IN) == 0 && 1642 tp->t_termios.c_iflag & IXOFF && 1643 tp->t_termios.c_cc[VSTOP] != _POSIX_VDISABLE) { 1644 /* 1645 * Input flow control. Only enter the high watermark when we 1646 * can successfully store the VSTOP character. 1647 */ 1648 if (ttyoutq_write_nofrag(&tp->t_outq, 1649 &tp->t_termios.c_cc[VSTOP], 1) == 0) 1650 tp->t_flags |= TF_HIWAT_IN; 1651 } else { 1652 /* No input flow control. */ 1653 tp->t_flags |= TF_HIWAT_IN; 1654 } 1655} 1656 1657void 1658tty_hiwat_in_unblock(struct tty *tp) 1659{ 1660 1661 if (tp->t_flags & TF_HIWAT_IN && 1662 tp->t_termios.c_iflag & IXOFF && 1663 tp->t_termios.c_cc[VSTART] != _POSIX_VDISABLE) { 1664 /* 1665 * Input flow control. Only leave the high watermark when we 1666 * can successfully store the VSTART character. 1667 */ 1668 if (ttyoutq_write_nofrag(&tp->t_outq, 1669 &tp->t_termios.c_cc[VSTART], 1) == 0) 1670 tp->t_flags &= ~TF_HIWAT_IN; 1671 } else { 1672 /* No input flow control. */ 1673 tp->t_flags &= ~TF_HIWAT_IN; 1674 } 1675 1676 if (!tty_gone(tp)) 1677 ttydevsw_inwakeup(tp); 1678} 1679 1680#include "opt_ddb.h" 1681#ifdef DDB 1682#include <ddb/ddb.h> 1683 1684static struct { 1685 int flag; 1686 char val; 1687} ttystates[] = { 1688#if 0 1689 { TF_NOPREFIX, 'N' }, 1690#endif 1691 { TF_INITLOCK, 'I' }, 1692 { TF_CALLOUT, 'C' }, 1693 1694 /* Keep these together -> 'Oi' and 'Oo'. */ 1695 { TF_OPENED, 'O' }, 1696 { TF_OPENED_IN, 'i' }, 1697 { TF_OPENED_OUT,'o' }, 1698 1699 { TF_GONE, 'G' }, 1700 { TF_OPENCLOSE, 'B' }, 1701 { TF_ASYNC, 'Y' }, 1702 { TF_LITERAL, 'L' }, 1703 1704 /* Keep these together -> 'Hi' and 'Ho'. */ 1705 { TF_HIWAT, 'H' }, 1706 { TF_HIWAT_IN, 'i' }, 1707 { TF_HIWAT_OUT, 'o' }, 1708 1709 { TF_STOPPED, 'S' }, 1710 { TF_EXCLUDE, 'X' }, 1711 { TF_BYPASS, 'l' }, 1712 { TF_ZOMBIE, 'Z' }, 1713 1714 { 0, '\0' }, 1715}; 1716 1717/* DDB command to show TTY statistics. */ 1718DB_SHOW_COMMAND(ttys, db_show_ttys) 1719{ 1720 struct tty *tp; 1721 size_t isiz, osiz; 1722 int i, j; 1723 1724 /* Make the output look like `pstat -t'. */ 1725 db_printf(" LINE INQ CAN LIN LOW OUTQ USE LOW " 1726 "COL SESS PGID STATE\n"); 1727 1728 TAILQ_FOREACH(tp, &tty_list, t_list) { 1729 isiz = tp->t_inq.ti_nblocks * TTYINQ_DATASIZE; 1730 osiz = tp->t_outq.to_nblocks * TTYOUTQ_DATASIZE; 1731 1732 db_printf("%10s %5zu %4u %4u %4zu %5zu %4u %4zu %5u %5d %5d ", 1733 tty_devname(tp), 1734 isiz, 1735 tp->t_inq.ti_linestart - tp->t_inq.ti_begin, 1736 tp->t_inq.ti_end - tp->t_inq.ti_linestart, 1737 isiz - tp->t_inlow, 1738 osiz, 1739 tp->t_outq.to_end - tp->t_outq.to_begin, 1740 osiz - tp->t_outlow, 1741 tp->t_column, 1742 tp->t_session ? tp->t_session->s_sid : 0, 1743 tp->t_pgrp ? tp->t_pgrp->pg_id : 0); 1744 1745 /* Flag bits. */ 1746 for (i = j = 0; ttystates[i].flag; i++) 1747 if (tp->t_flags & ttystates[i].flag) { 1748 db_printf("%c", ttystates[i].val); 1749 j++; 1750 } 1751 if (j == 0) 1752 db_printf("-"); 1753 db_printf("\n"); 1754 } 1755} 1756#endif /* DDB */ 1757