sys/kern/tty.c

   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("$FreeBSD$");
  32
  33 #include "opt_capsicum.h"
  34 #include "opt_compat.h"
  35
  36 #include <sys/param.h>
  37 #include <sys/capsicum.h>
  38 #include <sys/conf.h>
  39 #include <sys/cons.h>
  40 #include <sys/fcntl.h>
  41 #include <sys/file.h>
  42 #include <sys/filedesc.h>
  43 #include <sys/filio.h>
  44 #ifdef COMPAT_43TTY
  45 #include <sys/ioctl_compat.h>
  46 #endif /* COMPAT_43TTY */
  47 #include <sys/kernel.h>
  48 #include <sys/limits.h>
  49 #include <sys/malloc.h>
  50 #include <sys/mount.h>
  51 #include <sys/poll.h>
  52 #include <sys/priv.h>
  53 #include <sys/proc.h>
  54 #include <sys/serial.h>
  55 #include <sys/signal.h>
  56 #include <sys/stat.h>
  57 #include <sys/sx.h>
  58 #include <sys/sysctl.h>
  59 #include <sys/systm.h>
  60 #include <sys/tty.h>
  61 #include <sys/ttycom.h>
  62 #define TTYDEFCHARS
  63 #include <sys/ttydefaults.h>
  64 #undef TTYDEFCHARS
  65 #include <sys/ucred.h>
  66 #include <sys/vnode.h>
  67
  68 #include <machine/stdarg.h>
  69
  70 static MALLOC_DEFINE(M_TTY, "tty", "tty device");
  71
  72 static void tty_rel_free(struct tty *tp);
  73
  74 static TAILQ_HEAD(, tty) tty_list = TAILQ_HEAD_INITIALIZER(tty_list);
  75 static struct sx tty_list_sx;
  76 SX_SYSINIT(tty_list, &tty_list_sx, "tty list");
  77 static unsigned int tty_list_count = 0;
  78
  79 /* Character device of /dev/console. */
  80 static struct cdev      *dev_console;
  81 static const char       *dev_console_filename;
  82
  83 /*
  84  * Flags that are supported and stored by this implementation.
  85  */
  86 #define TTYSUP_IFLAG    (IGNBRK|BRKINT|IGNPAR|PARMRK|INPCK|ISTRIP|\
  87                         INLCR|IGNCR|ICRNL|IXON|IXOFF|IXANY|IMAXBEL)
  88 #define TTYSUP_OFLAG    (OPOST|ONLCR|TAB3|ONOEOT|OCRNL|ONOCR|ONLRET)
  89 #define TTYSUP_LFLAG    (ECHOKE|ECHOE|ECHOK|ECHO|ECHONL|ECHOPRT|\
  90                         ECHOCTL|ISIG|ICANON|ALTWERASE|IEXTEN|TOSTOP|\
  91                         FLUSHO|NOKERNINFO|NOFLSH)
  92 #define TTYSUP_CFLAG    (CIGNORE|CSIZE|CSTOPB|CREAD|PARENB|PARODD|\
  93                         HUPCL|CLOCAL|CCTS_OFLOW|CRTS_IFLOW|CDTR_IFLOW|\
  94                         CDSR_OFLOW|CCAR_OFLOW)
  95
  96 #define TTY_CALLOUT(tp,d) (dev2unit(d) & TTYUNIT_CALLOUT)
  97
  98 /*
  99  * Set TTY buffer sizes.
 100  */
 101
 102 #define TTYBUF_MAX      65536
 103
 104 static void
 105 tty_watermarks(struct tty *tp)
 106 {
 107         size_t bs = 0;
 108
 109         /* Provide an input buffer for 0.2 seconds of data. */
 110         if (tp->t_termios.c_cflag & CREAD)
 111                 bs = MIN(tp->t_termios.c_ispeed / 5, TTYBUF_MAX);
 112         ttyinq_setsize(&tp->t_inq, tp, bs);
 113
 114         /* Set low watermark at 10% (when 90% is available). */
 115         tp->t_inlow = (ttyinq_getallocatedsize(&tp->t_inq) * 9) / 10;
 116
 117         /* Provide an output buffer for 0.2 seconds of data. */
 118         bs = MIN(tp->t_termios.c_ospeed / 5, TTYBUF_MAX);
 119         ttyoutq_setsize(&tp->t_outq, tp, bs);
 120
 121         /* Set low watermark at 10% (when 90% is available). */
 122         tp->t_outlow = (ttyoutq_getallocatedsize(&tp->t_outq) * 9) / 10;
 123 }
 124
 125 static int
 126 tty_drain(struct tty *tp, int leaving)
 127 {
 128         size_t bytesused;
 129         int error, revokecnt;
 130
 131         if (ttyhook_hashook(tp, getc_inject))
 132                 /* buffer is inaccessible */
 133                 return (0);
 134
 135         while (ttyoutq_bytesused(&tp->t_outq) > 0 || ttydevsw_busy(tp)) {
 136                 ttydevsw_outwakeup(tp);
 137                 /* Could be handled synchronously. */
 138                 bytesused = ttyoutq_bytesused(&tp->t_outq);
 139                 if (bytesused == 0 && !ttydevsw_busy(tp))
 140                         return (0);
 141
 142                 /* Wait for data to be drained. */
 143                 if (leaving) {
 144                         revokecnt = tp->t_revokecnt;
 145                         error = tty_timedwait(tp, &tp->t_outwait, hz);
 146                         switch (error) {
 147                         case ERESTART:
 148                                 if (revokecnt != tp->t_revokecnt)
 149                                         error = 0;
 150                                 break;
 151                         case EWOULDBLOCK:
 152                                 if (ttyoutq_bytesused(&tp->t_outq) < bytesused)
 153                                         error = 0;
 154                                 break;
 155                         }
 156                 } else
 157                         error = tty_wait(tp, &tp->t_outwait);
 158
 159                 if (error)
 160                         return (error);
 161         }
 162
 163         return (0);
 164 }
 165
 166 /*
 167  * Though ttydev_enter() and ttydev_leave() seem to be related, they
 168  * don't have to be used together. ttydev_enter() is used by the cdev
 169  * operations to prevent an actual operation from being processed when
 170  * the TTY has been abandoned. ttydev_leave() is used by ttydev_open()
 171  * and ttydev_close() to determine whether per-TTY data should be
 172  * deallocated.
 173  */
 174
 175 static __inline int
 176 ttydev_enter(struct tty *tp)
 177 {
 178         tty_lock(tp);
 179
 180         if (tty_gone(tp) || !tty_opened(tp)) {
 181                 /* Device is already gone. */
 182                 tty_unlock(tp);
 183                 return (ENXIO);
 184         }
 185
 186         return (0);
 187 }
 188
 189 static void
 190 ttydev_leave(struct tty *tp)
 191 {
 192         tty_lock_assert(tp, MA_OWNED);
 193
 194         if (tty_opened(tp) || tp->t_flags & TF_OPENCLOSE) {
 195                 /* Device is still opened somewhere. */
 196                 tty_unlock(tp);
 197                 return;
 198         }
 199
 200         tp->t_flags |= TF_OPENCLOSE;
 201
 202         /* Stop asynchronous I/O. */
 203         funsetown(&tp->t_sigio);
 204
 205         /* Remove console TTY. */
 206         if (constty == tp)
 207                 constty_clear();
 208
 209         /* Drain any output. */
 210         MPASS((tp->t_flags & TF_STOPPED) == 0);
 211         if (!tty_gone(tp))
 212                 tty_drain(tp, 1);
 213
 214         ttydisc_close(tp);
 215
 216         /* Free i/o queues now since they might be large. */
 217         ttyinq_free(&tp->t_inq);
 218         tp->t_inlow = 0;
 219         ttyoutq_free(&tp->t_outq);
 220         tp->t_outlow = 0;
 221
 222         knlist_clear(&tp->t_inpoll.si_note, 1);
 223         knlist_clear(&tp->t_outpoll.si_note, 1);
 224
 225         if (!tty_gone(tp))
 226                 ttydevsw_close(tp);
 227
 228         tp->t_flags &= ~TF_OPENCLOSE;
 229         cv_broadcast(&tp->t_dcdwait);
 230         tty_rel_free(tp);
 231 }
 232
 233 /*
 234  * Operations that are exposed through the character device in /dev.
 235  */
 236 static int
 237 ttydev_open(struct cdev *dev, int oflags, int devtype, struct thread *td)
 238 {
 239         struct tty *tp;
 240         int error;
 241
 242         tp = dev->si_drv1;
 243         error = 0;
 244         tty_lock(tp);
 245         if (tty_gone(tp)) {
 246                 /* Device is already gone. */
 247                 tty_unlock(tp);
 248                 return (ENXIO);
 249         }
 250
 251         /*
 252          * Block when other processes are currently opening or closing
 253          * the TTY.
 254          */
 255         while (tp->t_flags & TF_OPENCLOSE) {
 256                 error = tty_wait(tp, &tp->t_dcdwait);
 257                 if (error != 0) {
 258                         tty_unlock(tp);
 259                         return (error);
 260                 }
 261         }
 262         tp->t_flags |= TF_OPENCLOSE;
 263
 264         /*
 265          * Make sure the "tty" and "cua" device cannot be opened at the
 266          * same time.
 267          */
 268         if (TTY_CALLOUT(tp, dev)) {
 269                 if (tp->t_flags & TF_OPENED_IN) {
 270                         error = EBUSY;
 271                         goto done;
 272                 }
 273         } else {
 274                 if (tp->t_flags & TF_OPENED_OUT) {
 275                         error = EBUSY;
 276                         goto done;
 277                 }
 278         }
 279
 280         if (tp->t_flags & TF_EXCLUDE && priv_check(td, PRIV_TTY_EXCLUSIVE)) {
 281                 error = EBUSY;
 282                 goto done;
 283         }
 284
 285         if (!tty_opened(tp)) {
 286                 /* Set proper termios flags. */
 287                 if (TTY_CALLOUT(tp, dev))
 288                         tp->t_termios = tp->t_termios_init_out;
 289                 else
 290                         tp->t_termios = tp->t_termios_init_in;
 291                 ttydevsw_param(tp, &tp->t_termios);
 292                 /* Prevent modem control on callout devices and /dev/console. */
 293                 if (TTY_CALLOUT(tp, dev) || dev == dev_console)
 294                         tp->t_termios.c_cflag |= CLOCAL;
 295
 296                 ttydevsw_modem(tp, SER_DTR|SER_RTS, 0);
 297
 298                 error = ttydevsw_open(tp);
 299                 if (error != 0)
 300                         goto done;
 301
 302                 ttydisc_open(tp);
 303                 tty_watermarks(tp); /* XXXGL: drops lock */
 304         }
 305
 306         /* Wait for Carrier Detect. */
 307         if ((oflags & O_NONBLOCK) == 0 &&
 308             (tp->t_termios.c_cflag & CLOCAL) == 0) {
 309                 while ((ttydevsw_modem(tp, 0, 0) & SER_DCD) == 0) {
 310                         error = tty_wait(tp, &tp->t_dcdwait);
 311                         if (error != 0)
 312                                 goto done;
 313                 }
 314         }
 315
 316         if (dev == dev_console)
 317                 tp->t_flags |= TF_OPENED_CONS;
 318         else if (TTY_CALLOUT(tp, dev))
 319                 tp->t_flags |= TF_OPENED_OUT;
 320         else
 321                 tp->t_flags |= TF_OPENED_IN;
 322
 323 done:   tp->t_flags &= ~TF_OPENCLOSE;
 324         cv_broadcast(&tp->t_dcdwait);
 325         ttydev_leave(tp);
 326
 327         return (error);
 328 }
 329
 330 static int
 331 ttydev_close(struct cdev *dev, int fflag, int devtype, struct thread *td)
 332 {
 333         struct tty *tp = dev->si_drv1;
 334
 335         tty_lock(tp);
 336
 337         /*
 338          * Don't actually close the device if it is being used as the
 339          * console.
 340          */
 341         MPASS((tp->t_flags & TF_OPENED) != TF_OPENED);
 342         if (dev == dev_console)
 343                 tp->t_flags &= ~TF_OPENED_CONS;
 344         else
 345                 tp->t_flags &= ~(TF_OPENED_IN|TF_OPENED_OUT);
 346
 347         if (tp->t_flags & TF_OPENED) {
 348                 tty_unlock(tp);
 349                 return (0);
 350         }
 351
 352         /*
 353          * This can only be called once. The callin and the callout
 354          * devices cannot be opened at the same time.
 355          */
 356         tp->t_flags &= ~(TF_EXCLUDE|TF_STOPPED);
 357
 358         /* Properly wake up threads that are stuck - revoke(). */
 359         tp->t_revokecnt++;
 360         tty_wakeup(tp, FREAD|FWRITE);
 361         cv_broadcast(&tp->t_bgwait);
 362         cv_broadcast(&tp->t_dcdwait);
 363
 364         ttydev_leave(tp);
 365
 366         return (0);
 367 }
 368
 369 static __inline int
 370 tty_is_ctty(struct tty *tp, struct proc *p)
 371 {
 372         tty_lock_assert(tp, MA_OWNED);
 373
 374         return (p->p_session == tp->t_session && p->p_flag & P_CONTROLT);
 375 }
 376
 377 int
 378 tty_wait_background(struct tty *tp, struct thread *td, int sig)
 379 {
 380         struct proc *p = td->td_proc;
 381         struct pgrp *pg;
 382         ksiginfo_t ksi;
 383         int error;
 384
 385         MPASS(sig == SIGTTIN || sig == SIGTTOU);
 386         tty_lock_assert(tp, MA_OWNED);
 387
 388         for (;;) {
 389                 PROC_LOCK(p);
 390                 /*
 391                  * The process should only sleep, when:
 392                  * - This terminal is the controling terminal
 393                  * - Its process group is not the foreground process
 394                  *   group
 395                  * - The parent process isn't waiting for the child to
 396                  *   exit
 397                  * - the signal to send to the process isn't masked
 398                  */
 399                 if (!tty_is_ctty(tp, p) || p->p_pgrp == tp->t_pgrp) {
 400                         /* Allow the action to happen. */
 401                         PROC_UNLOCK(p);
 402                         return (0);
 403                 }
 404
 405                 if (SIGISMEMBER(p->p_sigacts->ps_sigignore, sig) ||
 406                     SIGISMEMBER(td->td_sigmask, sig)) {
 407                         /* Only allow them in write()/ioctl(). */
 408                         PROC_UNLOCK(p);
 409                         return (sig == SIGTTOU ? 0 : EIO);
 410                 }
 411
 412                 pg = p->p_pgrp;
 413                 if (p->p_flag & P_PPWAIT || pg->pg_jobc == 0) {
 414                         /* Don't allow the action to happen. */
 415                         PROC_UNLOCK(p);
 416                         return (EIO);
 417                 }
 418                 PROC_UNLOCK(p);
 419
 420                 /*
 421                  * Send the signal and sleep until we're the new
 422                  * foreground process group.
 423                  */
 424                 if (sig != 0) {
 425                         ksiginfo_init(&ksi);
 426                         ksi.ksi_code = SI_KERNEL;
 427                         ksi.ksi_signo = sig;
 428                         sig = 0;
 429                 }
 430                 PGRP_LOCK(pg);
 431                 pgsignal(pg, ksi.ksi_signo, 1, &ksi);
 432                 PGRP_UNLOCK(pg);
 433
 434                 error = tty_wait(tp, &tp->t_bgwait);
 435                 if (error)
 436                         return (error);
 437         }
 438 }
 439
 440 static int
 441 ttydev_read(struct cdev *dev, struct uio *uio, int ioflag)
 442 {
 443         struct tty *tp = dev->si_drv1;
 444         int error;
 445
 446         error = ttydev_enter(tp);
 447         if (error)
 448                 goto done;
 449         error = ttydisc_read(tp, uio, ioflag);
 450         tty_unlock(tp);
 451
 452         /*
 453          * The read() call should not throw an error when the device is
 454          * being destroyed. Silently convert it to an EOF.
 455          */
 456 done:   if (error == ENXIO)
 457                 error = 0;
 458         return (error);
 459 }
 460
 461 static int
 462 ttydev_write(struct cdev *dev, struct uio *uio, int ioflag)
 463 {
 464         struct tty *tp = dev->si_drv1;
 465         int error;
 466
 467         error = ttydev_enter(tp);
 468         if (error)
 469                 return (error);
 470
 471         if (tp->t_termios.c_lflag & TOSTOP) {
 472                 error = tty_wait_background(tp, curthread, SIGTTOU);
 473                 if (error)
 474                         goto done;
 475         }
 476
 477         if (ioflag & IO_NDELAY && tp->t_flags & TF_BUSY_OUT) {
 478                 /* Allow non-blocking writes to bypass serialization. */
 479                 error = ttydisc_write(tp, uio, ioflag);
 480         } else {
 481                 /* Serialize write() calls. */
 482                 while (tp->t_flags & TF_BUSY_OUT) {
 483                         error = tty_wait(tp, &tp->t_outserwait);
 484                         if (error)
 485                                 goto done;
 486                 }
 487
 488                 tp->t_flags |= TF_BUSY_OUT;
 489                 error = ttydisc_write(tp, uio, ioflag);
 490                 tp->t_flags &= ~TF_BUSY_OUT;
 491                 cv_signal(&tp->t_outserwait);
 492         }
 493
 494 done:   tty_unlock(tp);
 495         return (error);
 496 }
 497
 498 static int
 499 ttydev_ioctl(struct cdev *dev, u_long cmd, caddr_t data, int fflag,
 500     struct thread *td)
 501 {
 502         struct tty *tp = dev->si_drv1;
 503         int error;
 504
 505         error = ttydev_enter(tp);
 506         if (error)
 507                 return (error);
 508
 509         switch (cmd) {
 510         case TIOCCBRK:
 511         case TIOCCONS:
 512         case TIOCDRAIN:
 513         case TIOCEXCL:
 514         case TIOCFLUSH:
 515         case TIOCNXCL:
 516         case TIOCSBRK:
 517         case TIOCSCTTY:
 518         case TIOCSETA:
 519         case TIOCSETAF:
 520         case TIOCSETAW:
 521         case TIOCSPGRP:
 522         case TIOCSTART:
 523         case TIOCSTAT:
 524         case TIOCSTI:
 525         case TIOCSTOP:
 526         case TIOCSWINSZ:
 527 #if 0
 528         case TIOCSDRAINWAIT:
 529         case TIOCSETD:
 530 #endif
 531 #ifdef COMPAT_43TTY
 532         case  TIOCLBIC:
 533         case  TIOCLBIS:
 534         case  TIOCLSET:
 535         case  TIOCSETC:
 536         case OTIOCSETD:
 537         case  TIOCSETN:
 538         case  TIOCSETP:
 539         case  TIOCSLTC:
 540 #endif /* COMPAT_43TTY */
 541                 /*
 542                  * If the ioctl() causes the TTY to be modified, let it
 543                  * wait in the background.
 544                  */
 545                 error = tty_wait_background(tp, curthread, SIGTTOU);
 546                 if (error)
 547                         goto done;
 548         }
 549
 550         if (cmd == TIOCSETA || cmd == TIOCSETAW || cmd == TIOCSETAF) {
 551                 struct termios *old = &tp->t_termios;
 552                 struct termios *new = (struct termios *)data;
 553                 struct termios *lock = TTY_CALLOUT(tp, dev) ?
 554                     &tp->t_termios_lock_out : &tp->t_termios_lock_in;
 555                 int cc;
 556
 557                 /*
 558                  * Lock state devices.  Just overwrite the values of the
 559                  * commands that are currently in use.
 560                  */
 561                 new->c_iflag = (old->c_iflag & lock->c_iflag) |
 562                     (new->c_iflag & ~lock->c_iflag);
 563                 new->c_oflag = (old->c_oflag & lock->c_oflag) |
 564                     (new->c_oflag & ~lock->c_oflag);
 565                 new->c_cflag = (old->c_cflag & lock->c_cflag) |
 566                     (new->c_cflag & ~lock->c_cflag);
 567                 new->c_lflag = (old->c_lflag & lock->c_lflag) |
 568                     (new->c_lflag & ~lock->c_lflag);
 569                 for (cc = 0; cc < NCCS; ++cc)
 570                         if (lock->c_cc[cc])
 571                                 new->c_cc[cc] = old->c_cc[cc];
 572                 if (lock->c_ispeed)
 573                         new->c_ispeed = old->c_ispeed;
 574                 if (lock->c_ospeed)
 575                         new->c_ospeed = old->c_ospeed;
 576         }
 577
 578         error = tty_ioctl(tp, cmd, data, fflag, td);
 579 done:   tty_unlock(tp);
 580
 581         return (error);
 582 }
 583
 584 static int
 585 ttydev_poll(struct cdev *dev, int events, struct thread *td)
 586 {
 587         struct tty *tp = dev->si_drv1;
 588         int error, revents = 0;
 589
 590         error = ttydev_enter(tp);
 591         if (error)
 592                 return ((events & (POLLIN|POLLRDNORM)) | POLLHUP);
 593
 594         if (events & (POLLIN|POLLRDNORM)) {
 595                 /* See if we can read something. */
 596                 if (ttydisc_read_poll(tp) > 0)
 597                         revents |= events & (POLLIN|POLLRDNORM);
 598         }
 599
 600         if (tp->t_flags & TF_ZOMBIE) {
 601                 /* Hangup flag on zombie state. */
 602                 revents |= POLLHUP;
 603         } else if (events & (POLLOUT|POLLWRNORM)) {
 604                 /* See if we can write something. */
 605                 if (ttydisc_write_poll(tp) > 0)
 606                         revents |= events & (POLLOUT|POLLWRNORM);
 607         }
 608
 609         if (revents == 0) {
 610                 if (events & (POLLIN|POLLRDNORM))
 611                         selrecord(td, &tp->t_inpoll);
 612                 if (events & (POLLOUT|POLLWRNORM))
 613                         selrecord(td, &tp->t_outpoll);
 614         }
 615
 616         tty_unlock(tp);
 617
 618         return (revents);
 619 }
 620
 621 static int
 622 ttydev_mmap(struct cdev *dev, vm_ooffset_t offset, vm_paddr_t *paddr,
 623     int nprot, vm_memattr_t *memattr)
 624 {
 625         struct tty *tp = dev->si_drv1;
 626         int error;
 627
 628         /* Handle mmap() through the driver. */
 629
 630         error = ttydev_enter(tp);
 631         if (error)
 632                 return (-1);
 633         error = ttydevsw_mmap(tp, offset, paddr, nprot, memattr);
 634         tty_unlock(tp);
 635
 636         return (error);
 637 }
 638
 639 /*
 640  * kqueue support.
 641  */
 642
 643 static void
 644 tty_kqops_read_detach(struct knote *kn)
 645 {
 646         struct tty *tp = kn->kn_hook;
 647
 648         knlist_remove(&tp->t_inpoll.si_note, kn, 0);
 649 }
 650
 651 static int
 652 tty_kqops_read_event(struct knote *kn, long hint)
 653 {
 654         struct tty *tp = kn->kn_hook;
 655
 656         tty_lock_assert(tp, MA_OWNED);
 657
 658         if (tty_gone(tp) || tp->t_flags & TF_ZOMBIE) {
 659                 kn->kn_flags |= EV_EOF;
 660                 return (1);
 661         } else {
 662                 kn->kn_data = ttydisc_read_poll(tp);
 663                 return (kn->kn_data > 0);
 664         }
 665 }
 666
 667 static void
 668 tty_kqops_write_detach(struct knote *kn)
 669 {
 670         struct tty *tp = kn->kn_hook;
 671
 672         knlist_remove(&tp->t_outpoll.si_note, kn, 0);
 673 }
 674
 675 static int
 676 tty_kqops_write_event(struct knote *kn, long hint)
 677 {
 678         struct tty *tp = kn->kn_hook;
 679
 680         tty_lock_assert(tp, MA_OWNED);
 681
 682         if (tty_gone(tp)) {
 683                 kn->kn_flags |= EV_EOF;
 684                 return (1);
 685         } else {
 686                 kn->kn_data = ttydisc_write_poll(tp);
 687                 return (kn->kn_data > 0);
 688         }
 689 }
 690
 691 static struct filterops tty_kqops_read = {
 692         .f_isfd = 1,
 693         .f_detach = tty_kqops_read_detach,
 694         .f_event = tty_kqops_read_event,
 695 };
 696 static struct filterops tty_kqops_write = {
 697         .f_isfd = 1,
 698         .f_detach = tty_kqops_write_detach,
 699         .f_event = tty_kqops_write_event,
 700 };
 701
 702 static int
 703 ttydev_kqfilter(struct cdev *dev, struct knote *kn)
 704 {
 705         struct tty *tp = dev->si_drv1;
 706         int error;
 707
 708         error = ttydev_enter(tp);
 709         if (error)
 710                 return (error);
 711
 712         switch (kn->kn_filter) {
 713         case EVFILT_READ:
 714                 kn->kn_hook = tp;
 715                 kn->kn_fop = &tty_kqops_read;
 716                 knlist_add(&tp->t_inpoll.si_note, kn, 1);
 717                 break;
 718         case EVFILT_WRITE:
 719                 kn->kn_hook = tp;
 720                 kn->kn_fop = &tty_kqops_write;
 721                 knlist_add(&tp->t_outpoll.si_note, kn, 1);
 722                 break;
 723         default:
 724                 error = EINVAL;
 725                 break;
 726         }
 727
 728         tty_unlock(tp);
 729         return (error);
 730 }
 731
 732 static struct cdevsw ttydev_cdevsw = {
 733         .d_version      = D_VERSION,
 734         .d_open         = ttydev_open,
 735         .d_close        = ttydev_close,
 736         .d_read         = ttydev_read,
 737         .d_write        = ttydev_write,
 738         .d_ioctl        = ttydev_ioctl,
 739         .d_kqfilter     = ttydev_kqfilter,
 740         .d_poll         = ttydev_poll,
 741         .d_mmap         = ttydev_mmap,
 742         .d_name         = "ttydev",
 743         .d_flags        = D_TTY,
 744 };
 745
 746 /*
 747  * Init/lock-state devices
 748  */
 749
 750 static int
 751 ttyil_open(struct cdev *dev, int oflags, int devtype, struct thread *td)
 752 {
 753         struct tty *tp;
 754         int error;
 755
 756         tp = dev->si_drv1;
 757         error = 0;
 758         tty_lock(tp);
 759         if (tty_gone(tp))
 760                 error = ENODEV;
 761         tty_unlock(tp);
 762
 763         return (error);
 764 }
 765
 766 static int
 767 ttyil_close(struct cdev *dev, int flag, int mode, struct thread *td)
 768 {
 769         return (0);
 770 }
 771
 772 static int
 773 ttyil_rdwr(struct cdev *dev, struct uio *uio, int ioflag)
 774 {
 775         return (ENODEV);
 776 }
 777
 778 static int
 779 ttyil_ioctl(struct cdev *dev, u_long cmd, caddr_t data, int fflag,
 780     struct thread *td)
 781 {
 782         struct tty *tp = dev->si_drv1;
 783         int error;
 784
 785         tty_lock(tp);
 786         if (tty_gone(tp)) {
 787                 error = ENODEV;
 788                 goto done;
 789         }
 790
 791         error = ttydevsw_cioctl(tp, dev2unit(dev), cmd, data, td);
 792         if (error != ENOIOCTL)
 793                 goto done;
 794         error = 0;
 795
 796         switch (cmd) {
 797         case TIOCGETA:
 798                 /* Obtain terminal flags through tcgetattr(). */
 799                 *(struct termios*)data = *(struct termios*)dev->si_drv2;
 800                 break;
 801         case TIOCSETA:
 802                 /* Set terminal flags through tcsetattr(). */
 803                 error = priv_check(td, PRIV_TTY_SETA);
 804                 if (error)
 805                         break;
 806                 *(struct termios*)dev->si_drv2 = *(struct termios*)data;
 807                 break;
 808         case TIOCGETD:
 809                 *(int *)data = TTYDISC;
 810                 break;
 811         case TIOCGWINSZ:
 812                 bzero(data, sizeof(struct winsize));
 813                 break;
 814         default:
 815                 error = ENOTTY;
 816         }
 817
 818 done:   tty_unlock(tp);
 819         return (error);
 820 }
 821
 822 static struct cdevsw ttyil_cdevsw = {
 823         .d_version      = D_VERSION,
 824         .d_open         = ttyil_open,
 825         .d_close        = ttyil_close,
 826         .d_read         = ttyil_rdwr,
 827         .d_write        = ttyil_rdwr,
 828         .d_ioctl        = ttyil_ioctl,
 829         .d_name         = "ttyil",
 830         .d_flags        = D_TTY,
 831 };
 832
 833 static void
 834 tty_init_termios(struct tty *tp)
 835 {
 836         struct termios *t = &tp->t_termios_init_in;
 837
 838         t->c_cflag = TTYDEF_CFLAG;
 839         t->c_iflag = TTYDEF_IFLAG;
 840         t->c_lflag = TTYDEF_LFLAG;
 841         t->c_oflag = TTYDEF_OFLAG;
 842         t->c_ispeed = TTYDEF_SPEED;
 843         t->c_ospeed = TTYDEF_SPEED;
 844         memcpy(&t->c_cc, ttydefchars, sizeof ttydefchars);
 845
 846         tp->t_termios_init_out = *t;
 847 }
 848
 849 void
 850 tty_init_console(struct tty *tp, speed_t s)
 851 {
 852         struct termios *ti = &tp->t_termios_init_in;
 853         struct termios *to = &tp->t_termios_init_out;
 854
 855         if (s != 0) {
 856                 ti->c_ispeed = ti->c_ospeed = s;
 857                 to->c_ispeed = to->c_ospeed = s;
 858         }
 859
 860         ti->c_cflag |= CLOCAL;
 861         to->c_cflag |= CLOCAL;
 862 }
 863
 864 /*
 865  * Standard device routine implementations, mostly meant for
 866  * pseudo-terminal device drivers. When a driver creates a new terminal
 867  * device class, missing routines are patched.
 868  */
 869
 870 static int
 871 ttydevsw_defopen(struct tty *tp)
 872 {
 873
 874         return (0);
 875 }
 876
 877 static void
 878 ttydevsw_defclose(struct tty *tp)
 879 {
 880 }
 881
 882 static void
 883 ttydevsw_defoutwakeup(struct tty *tp)
 884 {
 885
 886         panic("Terminal device has output, while not implemented");
 887 }
 888
 889 static void
 890 ttydevsw_definwakeup(struct tty *tp)
 891 {
 892 }
 893
 894 static int
 895 ttydevsw_defioctl(struct tty *tp, u_long cmd, caddr_t data, struct thread *td)
 896 {
 897
 898         return (ENOIOCTL);
 899 }
 900
 901 static int
 902 ttydevsw_defcioctl(struct tty *tp, int unit, u_long cmd, caddr_t data, struct thread *td)
 903 {
 904
 905         return (ENOIOCTL);
 906 }
 907
 908 static int
 909 ttydevsw_defparam(struct tty *tp, struct termios *t)
 910 {
 911
 912         /*
 913          * Allow the baud rate to be adjusted for pseudo-devices, but at
 914          * least restrict it to 115200 to prevent excessive buffer
 915          * usage.  Also disallow 0, to prevent foot shooting.
 916          */
 917         if (t->c_ispeed < B50)
 918                 t->c_ispeed = B50;
 919         else if (t->c_ispeed > B115200)
 920                 t->c_ispeed = B115200;
 921         if (t->c_ospeed < B50)
 922                 t->c_ospeed = B50;
 923         else if (t->c_ospeed > B115200)
 924                 t->c_ospeed = B115200;
 925         t->c_cflag |= CREAD;
 926
 927         return (0);
 928 }
 929
 930 static int
 931 ttydevsw_defmodem(struct tty *tp, int sigon, int sigoff)
 932 {
 933
 934         /* Simulate a carrier to make the TTY layer happy. */
 935         return (SER_DCD);
 936 }
 937
 938 static int
 939 ttydevsw_defmmap(struct tty *tp, vm_ooffset_t offset, vm_paddr_t *paddr,
 940     int nprot, vm_memattr_t *memattr)
 941 {
 942
 943         return (-1);
 944 }
 945
 946 static void
 947 ttydevsw_defpktnotify(struct tty *tp, char event)
 948 {
 949 }
 950
 951 static void
 952 ttydevsw_deffree(void *softc)
 953 {
 954
 955         panic("Terminal device freed without a free-handler");
 956 }
 957
 958 static bool
 959 ttydevsw_defbusy(struct tty *tp __unused)
 960 {
 961
 962         return (FALSE);
 963 }
 964
 965 /*
 966  * TTY allocation and deallocation. TTY devices can be deallocated when
 967  * the driver doesn't use it anymore, when the TTY isn't a session's
 968  * controlling TTY and when the device node isn't opened through devfs.
 969  */
 970
 971 struct tty *
 972 tty_alloc(struct ttydevsw *tsw, void *sc)
 973 {
 974
 975         return (tty_alloc_mutex(tsw, sc, NULL));
 976 }
 977
 978 struct tty *
 979 tty_alloc_mutex(struct ttydevsw *tsw, void *sc, struct mtx *mutex)
 980 {
 981         struct tty *tp;
 982
 983         /* Make sure the driver defines all routines. */
 984 #define PATCH_FUNC(x) do {                              \
 985         if (tsw->tsw_ ## x == NULL)                     \
 986                 tsw->tsw_ ## x = ttydevsw_def ## x;     \
 987 } while (0)
 988         PATCH_FUNC(open);
 989         PATCH_FUNC(close);
 990         PATCH_FUNC(outwakeup);
 991         PATCH_FUNC(inwakeup);
 992         PATCH_FUNC(ioctl);
 993         PATCH_FUNC(cioctl);
 994         PATCH_FUNC(param);
 995         PATCH_FUNC(modem);
 996         PATCH_FUNC(mmap);
 997         PATCH_FUNC(pktnotify);
 998         PATCH_FUNC(free);
 999         PATCH_FUNC(busy);
1000 #undef PATCH_FUNC
1001
1002         tp = malloc(sizeof(struct tty), M_TTY, M_WAITOK|M_ZERO);
1003         tp->t_devsw = tsw;
1004         tp->t_devswsoftc = sc;
1005         tp->t_flags = tsw->tsw_flags;
1006
1007         tty_init_termios(tp);
1008
1009         cv_init(&tp->t_inwait, "ttyin");
1010         cv_init(&tp->t_outwait, "ttyout");
1011         cv_init(&tp->t_outserwait, "ttyosr");
1012         cv_init(&tp->t_bgwait, "ttybg");
1013         cv_init(&tp->t_dcdwait, "ttydcd");
1014
1015         /* Allow drivers to use a custom mutex to lock the TTY. */
1016         if (mutex != NULL) {
1017                 tp->t_mtx = mutex;
1018         } else {
1019                 tp->t_mtx = &tp->t_mtxobj;
1020                 mtx_init(&tp->t_mtxobj, "ttymtx", NULL, MTX_DEF);
1021         }
1022
1023         knlist_init_mtx(&tp->t_inpoll.si_note, tp->t_mtx);
1024         knlist_init_mtx(&tp->t_outpoll.si_note, tp->t_mtx);
1025
1026         return (tp);
1027 }
1028
1029 static void
1030 tty_dealloc(void *arg)
1031 {
1032         struct tty *tp = arg;
1033
1034         /*
1035          * ttyydev_leave() usually frees the i/o queues earlier, but it is
1036          * not always called between queue allocation and here.  The queues
1037          * may be allocated by ioctls on a pty control device without the
1038          * corresponding pty slave device ever being open, or after it is
1039          * closed.
1040          */
1041         ttyinq_free(&tp->t_inq);
1042         ttyoutq_free(&tp->t_outq);
1043         seldrain(&tp->t_inpoll);
1044         seldrain(&tp->t_outpoll);
1045         knlist_destroy(&tp->t_inpoll.si_note);
1046         knlist_destroy(&tp->t_outpoll.si_note);
1047
1048         cv_destroy(&tp->t_inwait);
1049         cv_destroy(&tp->t_outwait);
1050         cv_destroy(&tp->t_bgwait);
1051         cv_destroy(&tp->t_dcdwait);
1052         cv_destroy(&tp->t_outserwait);
1053
1054         if (tp->t_mtx == &tp->t_mtxobj)
1055                 mtx_destroy(&tp->t_mtxobj);
1056         ttydevsw_free(tp);
1057         free(tp, M_TTY);
1058 }
1059
1060 static void
1061 tty_rel_free(struct tty *tp)
1062 {
1063         struct cdev *dev;
1064
1065         tty_lock_assert(tp, MA_OWNED);
1066
1067 #define TF_ACTIVITY     (TF_GONE|TF_OPENED|TF_HOOK|TF_OPENCLOSE)
1068         if (tp->t_sessioncnt != 0 || (tp->t_flags & TF_ACTIVITY) != TF_GONE) {
1069                 /* TTY is still in use. */
1070                 tty_unlock(tp);
1071                 return;
1072         }
1073
1074         /* TTY can be deallocated. */
1075         dev = tp->t_dev;
1076         tp->t_dev = NULL;
1077         tty_unlock(tp);
1078
1079         if (dev != NULL) {
1080                 sx_xlock(&tty_list_sx);
1081                 TAILQ_REMOVE(&tty_list, tp, t_list);
1082                 tty_list_count--;
1083                 sx_xunlock(&tty_list_sx);
1084                 destroy_dev_sched_cb(dev, tty_dealloc, tp);
1085         }
1086 }
1087
1088 void
1089 tty_rel_pgrp(struct tty *tp, struct pgrp *pg)
1090 {
1091         MPASS(tp->t_sessioncnt > 0);
1092         tty_lock_assert(tp, MA_OWNED);
1093
1094         if (tp->t_pgrp == pg)
1095                 tp->t_pgrp = NULL;
1096
1097         tty_unlock(tp);
1098 }
1099
1100 void
1101 tty_rel_sess(struct tty *tp, struct session *sess)
1102 {
1103         MPASS(tp->t_sessioncnt > 0);
1104
1105         /* Current session has left. */
1106         if (tp->t_session == sess) {
1107                 tp->t_session = NULL;
1108                 MPASS(tp->t_pgrp == NULL);
1109         }
1110         tp->t_sessioncnt--;
1111         tty_rel_free(tp);
1112 }
1113
1114 void
1115 tty_rel_gone(struct tty *tp)
1116 {
1117         MPASS(!tty_gone(tp));
1118
1119         /* Simulate carrier removal. */
1120         ttydisc_modem(tp, 0);
1121
1122         /* Wake up all blocked threads. */
1123         tty_wakeup(tp, FREAD|FWRITE);
1124         cv_broadcast(&tp->t_bgwait);
1125         cv_broadcast(&tp->t_dcdwait);
1126
1127         tp->t_flags |= TF_GONE;
1128         tty_rel_free(tp);
1129 }
1130
1131 /*
1132  * Exposing information about current TTY's through sysctl
1133  */
1134
1135 static void
1136 tty_to_xtty(struct tty *tp, struct xtty *xt)
1137 {
1138         tty_lock_assert(tp, MA_OWNED);
1139
1140         xt->xt_size = sizeof(struct xtty);
1141         xt->xt_insize = ttyinq_getsize(&tp->t_inq);
1142         xt->xt_incc = ttyinq_bytescanonicalized(&tp->t_inq);
1143         xt->xt_inlc = ttyinq_bytesline(&tp->t_inq);
1144         xt->xt_inlow = tp->t_inlow;
1145         xt->xt_outsize = ttyoutq_getsize(&tp->t_outq);
1146         xt->xt_outcc = ttyoutq_bytesused(&tp->t_outq);
1147         xt->xt_outlow = tp->t_outlow;
1148         xt->xt_column = tp->t_column;
1149         xt->xt_pgid = tp->t_pgrp ? tp->t_pgrp->pg_id : 0;
1150         xt->xt_sid = tp->t_session ? tp->t_session->s_sid : 0;
1151         xt->xt_flags = tp->t_flags;
1152         xt->xt_dev = tp->t_dev ? dev2udev(tp->t_dev) : NODEV;
1153 }
1154
1155 static int
1156 sysctl_kern_ttys(SYSCTL_HANDLER_ARGS)
1157 {
1158         unsigned long lsize;
1159         struct xtty *xtlist, *xt;
1160         struct tty *tp;
1161         int error;
1162
1163         sx_slock(&tty_list_sx);
1164         lsize = tty_list_count * sizeof(struct xtty);
1165         if (lsize == 0) {
1166                 sx_sunlock(&tty_list_sx);
1167                 return (0);
1168         }
1169
1170         xtlist = xt = malloc(lsize, M_TTY, M_WAITOK);
1171
1172         TAILQ_FOREACH(tp, &tty_list, t_list) {
1173                 tty_lock(tp);
1174                 tty_to_xtty(tp, xt);
1175                 tty_unlock(tp);
1176                 xt++;
1177         }
1178         sx_sunlock(&tty_list_sx);
1179
1180         error = SYSCTL_OUT(req, xtlist, lsize);
1181         free(xtlist, M_TTY);
1182         return (error);
1183 }
1184
1185 SYSCTL_PROC(_kern, OID_AUTO, ttys, CTLTYPE_OPAQUE|CTLFLAG_RD|CTLFLAG_MPSAFE,
1186         0, 0, sysctl_kern_ttys, "S,xtty", "List of TTYs");
1187
1188 /*
1189  * Device node creation. Device has been set up, now we can expose it to
1190  * the user.
1191  */
1192
1193 int
1194 tty_makedevf(struct tty *tp, struct ucred *cred, int flags,
1195     const char *fmt, ...)
1196 {
1197         va_list ap;
1198         struct make_dev_args args;
1199         struct cdev *dev, *init, *lock, *cua, *cinit, *clock;
1200         const char *prefix = "tty";
1201         char name[SPECNAMELEN - 3]; /* for "tty" and "cua". */
1202         uid_t uid;
1203         gid_t gid;
1204         mode_t mode;
1205         int error;
1206
1207         /* Remove "tty" prefix from devices like PTY's. */
1208         if (tp->t_flags & TF_NOPREFIX)
1209                 prefix = "";
1210
1211         va_start(ap, fmt);
1212         vsnrprintf(name, sizeof name, 32, fmt, ap);
1213         va_end(ap);
1214
1215         if (cred == NULL) {
1216                 /* System device. */
1217                 uid = UID_ROOT;
1218                 gid = GID_WHEEL;
1219                 mode = S_IRUSR|S_IWUSR;
1220         } else {
1221                 /* User device. */
1222                 uid = cred->cr_ruid;
1223                 gid = GID_TTY;
1224                 mode = S_IRUSR|S_IWUSR|S_IWGRP;
1225         }
1226
1227         flags = flags & TTYMK_CLONING ? MAKEDEV_REF : 0;
1228         flags |= MAKEDEV_CHECKNAME;
1229
1230         /* Master call-in device. */
1231         make_dev_args_init(&args);
1232         args.mda_flags = flags;
1233         args.mda_devsw = &ttydev_cdevsw;
1234         args.mda_cr = cred;
1235         args.mda_uid = uid;
1236         args.mda_gid = gid;
1237         args.mda_mode = mode;
1238         args.mda_si_drv1 = tp;
1239         error = make_dev_s(&args, &dev, "%s%s", prefix, name);
1240         if (error != 0)
1241                 return (error);
1242         tp->t_dev = dev;
1243
1244         init = lock = cua = cinit = clock = NULL;
1245
1246         /* Slave call-in devices. */
1247         if (tp->t_flags & TF_INITLOCK) {
1248                 args.mda_devsw = &ttyil_cdevsw;
1249                 args.mda_unit = TTYUNIT_INIT;
1250                 args.mda_si_drv1 = tp;
1251                 args.mda_si_drv2 = &tp->t_termios_init_in;
1252                 error = make_dev_s(&args, &init, "%s%s.init", prefix, name);
1253                 if (error != 0)
1254                         goto fail;
1255                 dev_depends(dev, init);
1256
1257                 args.mda_unit = TTYUNIT_LOCK;
1258                 args.mda_si_drv2 = &tp->t_termios_lock_in;
1259                 error = make_dev_s(&args, &lock, "%s%s.lock", prefix, name);
1260                 if (error != 0)
1261                         goto fail;
1262                 dev_depends(dev, lock);
1263         }
1264
1265         /* Call-out devices. */
1266         if (tp->t_flags & TF_CALLOUT) {
1267                 make_dev_args_init(&args);
1268                 args.mda_flags = flags;
1269                 args.mda_devsw = &ttydev_cdevsw;
1270                 args.mda_cr = cred;
1271                 args.mda_uid = UID_UUCP;
1272                 args.mda_gid = GID_DIALER;
1273                 args.mda_mode = 0660;
1274                 args.mda_unit = TTYUNIT_CALLOUT;
1275                 args.mda_si_drv1 = tp;
1276                 error = make_dev_s(&args, &cua, "cua%s", name);
1277                 if (error != 0)
1278                         goto fail;
1279                 dev_depends(dev, cua);
1280
1281                 /* Slave call-out devices. */
1282                 if (tp->t_flags & TF_INITLOCK) {
1283                         args.mda_devsw = &ttyil_cdevsw;
1284                         args.mda_unit = TTYUNIT_CALLOUT | TTYUNIT_INIT;
1285                         args.mda_si_drv2 = &tp->t_termios_init_out;
1286                         error = make_dev_s(&args, &cinit, "cua%s.init", name);
1287                         if (error != 0)
1288                                 goto fail;
1289                         dev_depends(dev, cinit);
1290
1291                         args.mda_unit = TTYUNIT_CALLOUT | TTYUNIT_LOCK;
1292                         args.mda_si_drv2 = &tp->t_termios_lock_out;
1293                         error = make_dev_s(&args, &clock, "cua%s.lock", name);
1294                         if (error != 0)
1295                                 goto fail;
1296                         dev_depends(dev, clock);
1297                 }
1298         }
1299
1300         sx_xlock(&tty_list_sx);
1301         TAILQ_INSERT_TAIL(&tty_list, tp, t_list);
1302         tty_list_count++;
1303         sx_xunlock(&tty_list_sx);
1304
1305         return (0);
1306
1307 fail:
1308         destroy_dev(dev);
1309         if (init)
1310                 destroy_dev(init);
1311         if (lock)
1312                 destroy_dev(lock);
1313         if (cinit)
1314                 destroy_dev(cinit);
1315         if (clock)
1316                 destroy_dev(clock);
1317
1318         return (error);
1319 }
1320
1321 /*
1322  * Signalling processes.
1323  */
1324
1325 void
1326 tty_signal_sessleader(struct tty *tp, int sig)
1327 {
1328         struct proc *p;
1329
1330         tty_lock_assert(tp, MA_OWNED);
1331         MPASS(sig >= 1 && sig < NSIG);
1332
1333         /* Make signals start output again. */
1334         tp->t_flags &= ~TF_STOPPED;
1335
1336         if (tp->t_session != NULL && tp->t_session->s_leader != NULL) {
1337                 p = tp->t_session->s_leader;
1338                 PROC_LOCK(p);
1339                 kern_psignal(p, sig);
1340                 PROC_UNLOCK(p);
1341         }
1342 }
1343
1344 void
1345 tty_signal_pgrp(struct tty *tp, int sig)
1346 {
1347         ksiginfo_t ksi;
1348
1349         tty_lock_assert(tp, MA_OWNED);
1350         MPASS(sig >= 1 && sig < NSIG);
1351
1352         /* Make signals start output again. */
1353         tp->t_flags &= ~TF_STOPPED;
1354
1355         if (sig == SIGINFO && !(tp->t_termios.c_lflag & NOKERNINFO))
1356                 tty_info(tp);
1357         if (tp->t_pgrp != NULL) {
1358                 ksiginfo_init(&ksi);
1359                 ksi.ksi_signo = sig;
1360                 ksi.ksi_code = SI_KERNEL;
1361                 PGRP_LOCK(tp->t_pgrp);
1362                 pgsignal(tp->t_pgrp, sig, 1, &ksi);
1363                 PGRP_UNLOCK(tp->t_pgrp);
1364         }
1365 }
1366
1367 void
1368 tty_wakeup(struct tty *tp, int flags)
1369 {
1370         if (tp->t_flags & TF_ASYNC && tp->t_sigio != NULL)
1371                 pgsigio(&tp->t_sigio, SIGIO, (tp->t_session != NULL));
1372
1373         if (flags & FWRITE) {
1374                 cv_broadcast(&tp->t_outwait);
1375                 selwakeup(&tp->t_outpoll);
1376                 KNOTE_LOCKED(&tp->t_outpoll.si_note, 0);
1377         }
1378         if (flags & FREAD) {
1379                 cv_broadcast(&tp->t_inwait);
1380                 selwakeup(&tp->t_inpoll);
1381                 KNOTE_LOCKED(&tp->t_inpoll.si_note, 0);
1382         }
1383 }
1384
1385 int
1386 tty_wait(struct tty *tp, struct cv *cv)
1387 {
1388         int error;
1389         int revokecnt = tp->t_revokecnt;
1390
1391         tty_lock_assert(tp, MA_OWNED|MA_NOTRECURSED);
1392         MPASS(!tty_gone(tp));
1393
1394         error = cv_wait_sig(cv, tp->t_mtx);
1395
1396         /* Bail out when the device slipped away. */
1397         if (tty_gone(tp))
1398                 return (ENXIO);
1399
1400         /* Restart the system call when we may have been revoked. */
1401         if (tp->t_revokecnt != revokecnt)
1402                 return (ERESTART);
1403
1404         return (error);
1405 }
1406
1407 int
1408 tty_timedwait(struct tty *tp, struct cv *cv, int hz)
1409 {
1410         int error;
1411         int revokecnt = tp->t_revokecnt;
1412
1413         tty_lock_assert(tp, MA_OWNED|MA_NOTRECURSED);
1414         MPASS(!tty_gone(tp));
1415
1416         error = cv_timedwait_sig(cv, tp->t_mtx, hz);
1417
1418         /* Bail out when the device slipped away. */
1419         if (tty_gone(tp))
1420                 return (ENXIO);
1421
1422         /* Restart the system call when we may have been revoked. */
1423         if (tp->t_revokecnt != revokecnt)
1424                 return (ERESTART);
1425
1426         return (error);
1427 }
1428
1429 void
1430 tty_flush(struct tty *tp, int flags)
1431 {
1432         if (flags & FWRITE) {
1433                 tp->t_flags &= ~TF_HIWAT_OUT;
1434                 ttyoutq_flush(&tp->t_outq);
1435                 tty_wakeup(tp, FWRITE);
1436                 ttydevsw_pktnotify(tp, TIOCPKT_FLUSHWRITE);
1437         }
1438         if (flags & FREAD) {
1439                 tty_hiwat_in_unblock(tp);
1440                 ttyinq_flush(&tp->t_inq);
1441                 ttydevsw_inwakeup(tp);
1442                 ttydevsw_pktnotify(tp, TIOCPKT_FLUSHREAD);
1443         }
1444 }
1445
1446 void
1447 tty_set_winsize(struct tty *tp, const struct winsize *wsz)
1448 {
1449
1450         if (memcmp(&tp->t_winsize, wsz, sizeof(*wsz)) == 0)
1451                 return;
1452         tp->t_winsize = *wsz;
1453         tty_signal_pgrp(tp, SIGWINCH);
1454 }
1455
1456 static int
1457 tty_generic_ioctl(struct tty *tp, u_long cmd, void *data, int fflag,
1458     struct thread *td)
1459 {
1460         int error;
1461
1462         switch (cmd) {
1463         /*
1464          * Modem commands.
1465          * The SER_* and TIOCM_* flags are the same, but one bit
1466          * shifted. I don't know why.
1467          */
1468         case TIOCSDTR:
1469                 ttydevsw_modem(tp, SER_DTR, 0);
1470                 return (0);
1471         case TIOCCDTR:
1472                 ttydevsw_modem(tp, 0, SER_DTR);
1473                 return (0);
1474         case TIOCMSET: {
1475                 int bits = *(int *)data;
1476                 ttydevsw_modem(tp,
1477                     (bits & (TIOCM_DTR | TIOCM_RTS)) >> 1,
1478                     ((~bits) & (TIOCM_DTR | TIOCM_RTS)) >> 1);
1479                 return (0);
1480         }
1481         case TIOCMBIS: {
1482                 int bits = *(int *)data;
1483                 ttydevsw_modem(tp, (bits & (TIOCM_DTR | TIOCM_RTS)) >> 1, 0);
1484                 return (0);
1485         }
1486         case TIOCMBIC: {
1487                 int bits = *(int *)data;
1488                 ttydevsw_modem(tp, 0, (bits & (TIOCM_DTR | TIOCM_RTS)) >> 1);
1489                 return (0);
1490         }
1491         case TIOCMGET:
1492                 *(int *)data = TIOCM_LE + (ttydevsw_modem(tp, 0, 0) << 1);
1493                 return (0);
1494
1495         case FIOASYNC:
1496                 if (*(int *)data)
1497                         tp->t_flags |= TF_ASYNC;
1498                 else
1499                         tp->t_flags &= ~TF_ASYNC;
1500                 return (0);
1501         case FIONBIO:
1502                 /* This device supports non-blocking operation. */
1503                 return (0);
1504         case FIONREAD:
1505                 *(int *)data = ttyinq_bytescanonicalized(&tp->t_inq);
1506                 return (0);
1507         case FIONWRITE:
1508         case TIOCOUTQ:
1509                 *(int *)data = ttyoutq_bytesused(&tp->t_outq);
1510                 return (0);
1511         case FIOSETOWN:
1512                 if (tp->t_session != NULL && !tty_is_ctty(tp, td->td_proc))
1513                         /* Not allowed to set ownership. */
1514                         return (ENOTTY);
1515
1516                 /* Temporarily unlock the TTY to set ownership. */
1517                 tty_unlock(tp);
1518                 error = fsetown(*(int *)data, &tp->t_sigio);
1519                 tty_lock(tp);
1520                 return (error);
1521         case FIOGETOWN:
1522                 if (tp->t_session != NULL && !tty_is_ctty(tp, td->td_proc))
1523                         /* Not allowed to set ownership. */
1524                         return (ENOTTY);
1525
1526                 /* Get ownership. */
1527                 *(int *)data = fgetown(&tp->t_sigio);
1528                 return (0);
1529         case TIOCGETA:
1530                 /* Obtain terminal flags through tcgetattr(). */
1531                 *(struct termios*)data = tp->t_termios;
1532                 return (0);
1533         case TIOCSETA:
1534         case TIOCSETAW:
1535         case TIOCSETAF: {
1536                 struct termios *t = data;
1537
1538                 /*
1539                  * Who makes up these funny rules? According to POSIX,
1540                  * input baud rate is set equal to the output baud rate
1541                  * when zero.
1542                  */
1543                 if (t->c_ispeed == 0)
1544                         t->c_ispeed = t->c_ospeed;
1545
1546                 /* Discard any unsupported bits. */
1547                 t->c_iflag &= TTYSUP_IFLAG;
1548                 t->c_oflag &= TTYSUP_OFLAG;
1549                 t->c_lflag &= TTYSUP_LFLAG;
1550                 t->c_cflag &= TTYSUP_CFLAG;
1551
1552                 /* Set terminal flags through tcsetattr(). */
1553                 if (cmd == TIOCSETAW || cmd == TIOCSETAF) {
1554                         error = tty_drain(tp, 0);
1555                         if (error)
1556                                 return (error);
1557                         if (cmd == TIOCSETAF)
1558                                 tty_flush(tp, FREAD);
1559                 }
1560
1561                 /*
1562                  * Only call param() when the flags really change.
1563                  */
1564                 if ((t->c_cflag & CIGNORE) == 0 &&
1565                     (tp->t_termios.c_cflag != t->c_cflag ||
1566                     ((tp->t_termios.c_iflag ^ t->c_iflag) &
1567                     (IXON|IXOFF|IXANY)) ||
1568                     tp->t_termios.c_ispeed != t->c_ispeed ||
1569                     tp->t_termios.c_ospeed != t->c_ospeed)) {
1570                         error = ttydevsw_param(tp, t);
1571                         if (error)
1572                                 return (error);
1573
1574                         /* XXX: CLOCAL? */
1575
1576                         tp->t_termios.c_cflag = t->c_cflag & ~CIGNORE;
1577                         tp->t_termios.c_ispeed = t->c_ispeed;
1578                         tp->t_termios.c_ospeed = t->c_ospeed;
1579
1580                         /* Baud rate has changed - update watermarks. */
1581                         tty_watermarks(tp);
1582                 }
1583
1584                 /* Copy new non-device driver parameters. */
1585                 tp->t_termios.c_iflag = t->c_iflag;
1586                 tp->t_termios.c_oflag = t->c_oflag;
1587                 tp->t_termios.c_lflag = t->c_lflag;
1588                 memcpy(&tp->t_termios.c_cc, t->c_cc, sizeof t->c_cc);
1589
1590                 ttydisc_optimize(tp);
1591
1592                 if ((t->c_lflag & ICANON) == 0) {
1593                         /*
1594                          * When in non-canonical mode, wake up all
1595                          * readers. Canonicalize any partial input. VMIN
1596                          * and VTIME could also be adjusted.
1597                          */
1598                         ttyinq_canonicalize(&tp->t_inq);
1599                         tty_wakeup(tp, FREAD);
1600                 }
1601
1602                 /*
1603                  * For packet mode: notify the PTY consumer that VSTOP
1604                  * and VSTART may have been changed.
1605                  */
1606                 if (tp->t_termios.c_iflag & IXON &&
1607                     tp->t_termios.c_cc[VSTOP] == CTRL('S') &&
1608                     tp->t_termios.c_cc[VSTART] == CTRL('Q'))
1609                         ttydevsw_pktnotify(tp, TIOCPKT_DOSTOP);
1610                 else
1611                         ttydevsw_pktnotify(tp, TIOCPKT_NOSTOP);
1612                 return (0);
1613         }
1614         case TIOCGETD:
1615                 /* For compatibility - we only support TTYDISC. */
1616                 *(int *)data = TTYDISC;
1617                 return (0);
1618         case TIOCGPGRP:
1619                 if (!tty_is_ctty(tp, td->td_proc))
1620                         return (ENOTTY);
1621
1622                 if (tp->t_pgrp != NULL)
1623                         *(int *)data = tp->t_pgrp->pg_id;
1624                 else
1625                         *(int *)data = NO_PID;
1626                 return (0);
1627         case TIOCGSID:
1628                 if (!tty_is_ctty(tp, td->td_proc))
1629                         return (ENOTTY);
1630
1631                 MPASS(tp->t_session);
1632                 *(int *)data = tp->t_session->s_sid;
1633                 return (0);
1634         case TIOCSCTTY: {
1635                 struct proc *p = td->td_proc;
1636
1637                 /* XXX: This looks awful. */
1638                 tty_unlock(tp);
1639                 sx_xlock(&proctree_lock);
1640                 tty_lock(tp);
1641
1642                 if (!SESS_LEADER(p)) {
1643                         /* Only the session leader may do this. */
1644                         sx_xunlock(&proctree_lock);
1645                         return (EPERM);
1646                 }
1647
1648                 if (tp->t_session != NULL && tp->t_session == p->p_session) {
1649                         /* This is already our controlling TTY. */
1650                         sx_xunlock(&proctree_lock);
1651                         return (0);
1652                 }
1653
1654                 if (p->p_session->s_ttyp != NULL ||
1655                     (tp->t_session != NULL && tp->t_session->s_ttyvp != NULL &&
1656                     tp->t_session->s_ttyvp->v_type != VBAD)) {
1657                         /*
1658                          * There is already a relation between a TTY and
1659                          * a session, or the caller is not the session
1660                          * leader.
1661                          *
1662                          * Allow the TTY to be stolen when the vnode is
1663                          * invalid, but the reference to the TTY is
1664                          * still active.  This allows immediate reuse of
1665                          * TTYs of which the session leader has been
1666                          * killed or the TTY revoked.
1667                          */
1668                         sx_xunlock(&proctree_lock);
1669                         return (EPERM);
1670                 }
1671
1672                 /* Connect the session to the TTY. */
1673                 tp->t_session = p->p_session;
1674                 tp->t_session->s_ttyp = tp;
1675                 tp->t_sessioncnt++;
1676                 sx_xunlock(&proctree_lock);
1677
1678                 /* Assign foreground process group. */
1679                 tp->t_pgrp = p->p_pgrp;
1680                 PROC_LOCK(p);
1681                 p->p_flag |= P_CONTROLT;
1682                 PROC_UNLOCK(p);
1683
1684                 return (0);
1685         }
1686         case TIOCSPGRP: {
1687                 struct pgrp *pg;
1688
1689                 /*
1690                  * XXX: Temporarily unlock the TTY to locate the process
1691                  * group. This code would be lot nicer if we would ever
1692                  * decompose proctree_lock.
1693                  */
1694                 tty_unlock(tp);
1695                 sx_slock(&proctree_lock);
1696                 pg = pgfind(*(int *)data);
1697                 if (pg != NULL)
1698                         PGRP_UNLOCK(pg);
1699                 if (pg == NULL || pg->pg_session != td->td_proc->p_session) {
1700                         sx_sunlock(&proctree_lock);
1701                         tty_lock(tp);
1702                         return (EPERM);
1703                 }
1704                 tty_lock(tp);
1705
1706                 /*
1707                  * Determine if this TTY is the controlling TTY after
1708                  * relocking the TTY.
1709                  */
1710                 if (!tty_is_ctty(tp, td->td_proc)) {
1711                         sx_sunlock(&proctree_lock);
1712                         return (ENOTTY);
1713                 }
1714                 tp->t_pgrp = pg;
1715                 sx_sunlock(&proctree_lock);
1716
1717                 /* Wake up the background process groups. */
1718                 cv_broadcast(&tp->t_bgwait);
1719                 return (0);
1720         }
1721         case TIOCFLUSH: {
1722                 int flags = *(int *)data;
1723
1724                 if (flags == 0)
1725                         flags = (FREAD|FWRITE);
1726                 else
1727                         flags &= (FREAD|FWRITE);
1728                 tty_flush(tp, flags);
1729                 return (0);
1730         }
1731         case TIOCDRAIN:
1732                 /* Drain TTY output. */
1733                 return tty_drain(tp, 0);
1734         case TIOCCONS:
1735                 /* Set terminal as console TTY. */
1736                 if (*(int *)data) {
1737                         error = priv_check(td, PRIV_TTY_CONSOLE);
1738                         if (error)
1739                                 return (error);
1740
1741                         /*
1742                          * XXX: constty should really need to be locked!
1743                          * XXX: allow disconnected constty's to be stolen!
1744                          */
1745
1746                         if (constty == tp)
1747                                 return (0);
1748                         if (constty != NULL)
1749                                 return (EBUSY);
1750
1751                         tty_unlock(tp);
1752                         constty_set(tp);
1753                         tty_lock(tp);
1754                 } else if (constty == tp) {
1755                         constty_clear();
1756                 }
1757                 return (0);
1758         case TIOCGWINSZ:
1759                 /* Obtain window size. */
1760                 *(struct winsize*)data = tp->t_winsize;
1761                 return (0);
1762         case TIOCSWINSZ:
1763                 /* Set window size. */
1764                 tty_set_winsize(tp, data);
1765                 return (0);
1766         case TIOCEXCL:
1767                 tp->t_flags |= TF_EXCLUDE;
1768                 return (0);
1769         case TIOCNXCL:
1770                 tp->t_flags &= ~TF_EXCLUDE;
1771                 return (0);
1772         case TIOCSTOP:
1773                 tp->t_flags |= TF_STOPPED;
1774                 ttydevsw_pktnotify(tp, TIOCPKT_STOP);
1775                 return (0);
1776         case TIOCSTART:
1777                 tp->t_flags &= ~TF_STOPPED;
1778                 ttydevsw_outwakeup(tp);
1779                 ttydevsw_pktnotify(tp, TIOCPKT_START);
1780                 return (0);
1781         case TIOCSTAT:
1782                 tty_info(tp);
1783                 return (0);
1784         case TIOCSTI:
1785                 if ((fflag & FREAD) == 0 && priv_check(td, PRIV_TTY_STI))
1786                         return (EPERM);
1787                 if (!tty_is_ctty(tp, td->td_proc) &&
1788                     priv_check(td, PRIV_TTY_STI))
1789                         return (EACCES);
1790                 ttydisc_rint(tp, *(char *)data, 0);
1791                 ttydisc_rint_done(tp);
1792                 return (0);
1793         }
1794
1795 #ifdef COMPAT_43TTY
1796         return tty_ioctl_compat(tp, cmd, data, fflag, td);
1797 #else /* !COMPAT_43TTY */
1798         return (ENOIOCTL);
1799 #endif /* COMPAT_43TTY */
1800 }
1801
1802 int
1803 tty_ioctl(struct tty *tp, u_long cmd, void *data, int fflag, struct thread *td)
1804 {
1805         int error;
1806
1807         tty_lock_assert(tp, MA_OWNED);
1808
1809         if (tty_gone(tp))
1810                 return (ENXIO);
1811
1812         error = ttydevsw_ioctl(tp, cmd, data, td);
1813         if (error == ENOIOCTL)
1814                 error = tty_generic_ioctl(tp, cmd, data, fflag, td);
1815
1816         return (error);
1817 }
1818
1819 dev_t
1820 tty_udev(struct tty *tp)
1821 {
1822         if (tp->t_dev)
1823                 return dev2udev(tp->t_dev);
1824         else
1825                 return NODEV;
1826 }
1827
1828 int
1829 tty_checkoutq(struct tty *tp)
1830 {
1831
1832         /* 256 bytes should be enough to print a log message. */
1833         return (ttyoutq_bytesleft(&tp->t_outq) >= 256);
1834 }
1835
1836 void
1837 tty_hiwat_in_block(struct tty *tp)
1838 {
1839
1840         if ((tp->t_flags & TF_HIWAT_IN) == 0 &&
1841             tp->t_termios.c_iflag & IXOFF &&
1842             tp->t_termios.c_cc[VSTOP] != _POSIX_VDISABLE) {
1843                 /*
1844                  * Input flow control. Only enter the high watermark when we
1845                  * can successfully store the VSTOP character.
1846                  */
1847                 if (ttyoutq_write_nofrag(&tp->t_outq,
1848                     &tp->t_termios.c_cc[VSTOP], 1) == 0)
1849                         tp->t_flags |= TF_HIWAT_IN;
1850         } else {
1851                 /* No input flow control. */
1852                 tp->t_flags |= TF_HIWAT_IN;
1853         }
1854 }
1855
1856 void
1857 tty_hiwat_in_unblock(struct tty *tp)
1858 {
1859
1860         if (tp->t_flags & TF_HIWAT_IN &&
1861             tp->t_termios.c_iflag & IXOFF &&
1862             tp->t_termios.c_cc[VSTART] != _POSIX_VDISABLE) {
1863                 /*
1864                  * Input flow control. Only leave the high watermark when we
1865                  * can successfully store the VSTART character.
1866                  */
1867                 if (ttyoutq_write_nofrag(&tp->t_outq,
1868                     &tp->t_termios.c_cc[VSTART], 1) == 0)
1869                         tp->t_flags &= ~TF_HIWAT_IN;
1870         } else {
1871                 /* No input flow control. */
1872                 tp->t_flags &= ~TF_HIWAT_IN;
1873         }
1874
1875         if (!tty_gone(tp))
1876                 ttydevsw_inwakeup(tp);
1877 }
1878
1879 /*
1880  * TTY hooks interface.
1881  */
1882
1883 static int
1884 ttyhook_defrint(struct tty *tp, char c, int flags)
1885 {
1886
1887         if (ttyhook_rint_bypass(tp, &c, 1) != 1)
1888                 return (-1);
1889
1890         return (0);
1891 }
1892
1893 int
1894 ttyhook_register(struct tty **rtp, struct proc *p, int fd,
1895     struct ttyhook *th, void *softc)
1896 {
1897         struct tty *tp;
1898         struct file *fp;
1899         struct cdev *dev;
1900         struct cdevsw *cdp;
1901         struct filedesc *fdp;
1902         cap_rights_t rights;
1903         int error, ref;
1904
1905         /* Validate the file descriptor. */
1906         fdp = p->p_fd;
1907         error = fget_unlocked(fdp, fd, cap_rights_init(&rights, CAP_TTYHOOK),
1908             &fp, NULL);
1909         if (error != 0)
1910                 return (error);
1911         if (fp->f_ops == &badfileops) {
1912                 error = EBADF;
1913                 goto done1;
1914         }
1915
1916         /*
1917          * Make sure the vnode is bound to a character device.
1918          * Unlocked check for the vnode type is ok there, because we
1919          * only shall prevent calling devvn_refthread on the file that
1920          * never has been opened over a character device.
1921          */
1922         if (fp->f_type != DTYPE_VNODE || fp->f_vnode->v_type != VCHR) {
1923                 error = EINVAL;
1924                 goto done1;
1925         }
1926
1927         /* Make sure it is a TTY. */
1928         cdp = devvn_refthread(fp->f_vnode, &dev, &ref);
1929         if (cdp == NULL) {
1930                 error = ENXIO;
1931                 goto done1;
1932         }
1933         if (dev != fp->f_data) {
1934                 error = ENXIO;
1935                 goto done2;
1936         }
1937         if (cdp != &ttydev_cdevsw) {
1938                 error = ENOTTY;
1939                 goto done2;
1940         }
1941         tp = dev->si_drv1;
1942
1943         /* Try to attach the hook to the TTY. */
1944         error = EBUSY;
1945         tty_lock(tp);
1946         MPASS((tp->t_hook == NULL) == ((tp->t_flags & TF_HOOK) == 0));
1947         if (tp->t_flags & TF_HOOK)
1948                 goto done3;
1949
1950         tp->t_flags |= TF_HOOK;
1951         tp->t_hook = th;
1952         tp->t_hooksoftc = softc;
1953         *rtp = tp;
1954         error = 0;
1955
1956         /* Maybe we can switch into bypass mode now. */
1957         ttydisc_optimize(tp);
1958
1959         /* Silently convert rint() calls to rint_bypass() when possible. */
1960         if (!ttyhook_hashook(tp, rint) && ttyhook_hashook(tp, rint_bypass))
1961                 th->th_rint = ttyhook_defrint;
1962
1963 done3:  tty_unlock(tp);
1964 done2:  dev_relthread(dev, ref);
1965 done1:  fdrop(fp, curthread);
1966         return (error);
1967 }
1968
1969 void
1970 ttyhook_unregister(struct tty *tp)
1971 {
1972
1973         tty_lock_assert(tp, MA_OWNED);
1974         MPASS(tp->t_flags & TF_HOOK);
1975
1976         /* Disconnect the hook. */
1977         tp->t_flags &= ~TF_HOOK;
1978         tp->t_hook = NULL;
1979
1980         /* Maybe we need to leave bypass mode. */
1981         ttydisc_optimize(tp);
1982
1983         /* Maybe deallocate the TTY as well. */
1984         tty_rel_free(tp);
1985 }
1986
1987 /*
1988  * /dev/console handling.
1989  */
1990
1991 static int
1992 ttyconsdev_open(struct cdev *dev, int oflags, int devtype, struct thread *td)
1993 {
1994         struct tty *tp;
1995
1996         /* System has no console device. */
1997         if (dev_console_filename == NULL)
1998                 return (ENXIO);
1999
2000         /* Look up corresponding TTY by device name. */
2001         sx_slock(&tty_list_sx);
2002         TAILQ_FOREACH(tp, &tty_list, t_list) {
2003                 if (strcmp(dev_console_filename, tty_devname(tp)) == 0) {
2004                         dev_console->si_drv1 = tp;
2005                         break;
2006                 }
2007         }
2008         sx_sunlock(&tty_list_sx);
2009
2010         /* System console has no TTY associated. */
2011         if (dev_console->si_drv1 == NULL)
2012                 return (ENXIO);
2013
2014         return (ttydev_open(dev, oflags, devtype, td));
2015 }
2016
2017 static int
2018 ttyconsdev_write(struct cdev *dev, struct uio *uio, int ioflag)
2019 {
2020
2021         log_console(uio);
2022
2023         return (ttydev_write(dev, uio, ioflag));
2024 }
2025
2026 /*
2027  * /dev/console is a little different than normal TTY's.  When opened,
2028  * it determines which TTY to use.  When data gets written to it, it
2029  * will be logged in the kernel message buffer.
2030  */
2031 static struct cdevsw ttyconsdev_cdevsw = {
2032         .d_version      = D_VERSION,
2033         .d_open         = ttyconsdev_open,
2034         .d_close        = ttydev_close,
2035         .d_read         = ttydev_read,
2036         .d_write        = ttyconsdev_write,
2037         .d_ioctl        = ttydev_ioctl,
2038         .d_kqfilter     = ttydev_kqfilter,
2039         .d_poll         = ttydev_poll,
2040         .d_mmap         = ttydev_mmap,
2041         .d_name         = "ttyconsdev",
2042         .d_flags        = D_TTY,
2043 };
2044
2045 static void
2046 ttyconsdev_init(void *unused)
2047 {
2048
2049         dev_console = make_dev_credf(MAKEDEV_ETERNAL, &ttyconsdev_cdevsw, 0,
2050             NULL, UID_ROOT, GID_WHEEL, 0600, "console");
2051 }
2052
2053 SYSINIT(tty, SI_SUB_DRIVERS, SI_ORDER_FIRST, ttyconsdev_init, NULL);
2054
2055 void
2056 ttyconsdev_select(const char *name)
2057 {
2058
2059         dev_console_filename = name;
2060 }
2061
2062 /*
2063  * Debugging routines.
2064  */
2065
2066 #include "opt_ddb.h"
2067 #ifdef DDB
2068 #include <ddb/ddb.h>
2069 #include <ddb/db_sym.h>
2070
2071 static struct {
2072         int flag;
2073         char val;
2074 } ttystates[] = {
2075 #if 0
2076         { TF_NOPREFIX,          'N' },
2077 #endif
2078         { TF_INITLOCK,          'I' },
2079         { TF_CALLOUT,           'C' },
2080
2081         /* Keep these together -> 'Oi' and 'Oo'. */
2082         { TF_OPENED,            'O' },
2083         { TF_OPENED_IN,         'i' },
2084         { TF_OPENED_OUT,        'o' },
2085         { TF_OPENED_CONS,       'c' },
2086
2087         { TF_GONE,              'G' },
2088         { TF_OPENCLOSE,         'B' },
2089         { TF_ASYNC,             'Y' },
2090         { TF_LITERAL,           'L' },
2091
2092         /* Keep these together -> 'Hi' and 'Ho'. */
2093         { TF_HIWAT,             'H' },
2094         { TF_HIWAT_IN,          'i' },
2095         { TF_HIWAT_OUT,         'o' },
2096
2097         { TF_STOPPED,           'S' },
2098         { TF_EXCLUDE,           'X' },
2099         { TF_BYPASS,            'l' },
2100         { TF_ZOMBIE,            'Z' },
2101         { TF_HOOK,              's' },
2102
2103         /* Keep these together -> 'bi' and 'bo'. */
2104         { TF_BUSY,              'b' },
2105         { TF_BUSY_IN,           'i' },
2106         { TF_BUSY_OUT,          'o' },
2107
2108         { 0,                    '\0'},
2109 };
2110
2111 #define TTY_FLAG_BITS \
2112         "\20\1NOPREFIX\2INITLOCK\3CALLOUT\4OPENED_IN\5OPENED_OUT\6GONE" \
2113         "\7OPENCLOSE\10ASYNC\11LITERAL\12HIWAT_IN\13HIWAT_OUT\14STOPPED" \
2114         "\15EXCLUDE\16BYPASS\17ZOMBIE\20HOOK"
2115
2116 #define DB_PRINTSYM(name, addr) \
2117         db_printf("%s  " #name ": ", sep); \
2118         db_printsym((db_addr_t) addr, DB_STGY_ANY); \
2119         db_printf("\n");
2120
2121 static void
2122 _db_show_devsw(const char *sep, const struct ttydevsw *tsw)
2123 {
2124         db_printf("%sdevsw: ", sep);
2125         db_printsym((db_addr_t)tsw, DB_STGY_ANY);
2126         db_printf(" (%p)\n", tsw);
2127         DB_PRINTSYM(open, tsw->tsw_open);
2128         DB_PRINTSYM(close, tsw->tsw_close);
2129         DB_PRINTSYM(outwakeup, tsw->tsw_outwakeup);
2130         DB_PRINTSYM(inwakeup, tsw->tsw_inwakeup);
2131         DB_PRINTSYM(ioctl, tsw->tsw_ioctl);
2132         DB_PRINTSYM(param, tsw->tsw_param);
2133         DB_PRINTSYM(modem, tsw->tsw_modem);
2134         DB_PRINTSYM(mmap, tsw->tsw_mmap);
2135         DB_PRINTSYM(pktnotify, tsw->tsw_pktnotify);
2136         DB_PRINTSYM(free, tsw->tsw_free);
2137 }
2138 static void
2139 _db_show_hooks(const char *sep, const struct ttyhook *th)
2140 {
2141         db_printf("%shook: ", sep);
2142         db_printsym((db_addr_t)th, DB_STGY_ANY);
2143         db_printf(" (%p)\n", th);
2144         if (th == NULL)
2145                 return;
2146         DB_PRINTSYM(rint, th->th_rint);
2147         DB_PRINTSYM(rint_bypass, th->th_rint_bypass);
2148         DB_PRINTSYM(rint_done, th->th_rint_done);
2149         DB_PRINTSYM(rint_poll, th->th_rint_poll);
2150         DB_PRINTSYM(getc_inject, th->th_getc_inject);
2151         DB_PRINTSYM(getc_capture, th->th_getc_capture);
2152         DB_PRINTSYM(getc_poll, th->th_getc_poll);
2153         DB_PRINTSYM(close, th->th_close);
2154 }
2155
2156 static void
2157 _db_show_termios(const char *name, const struct termios *t)
2158 {
2159
2160         db_printf("%s: iflag 0x%x oflag 0x%x cflag 0x%x "
2161             "lflag 0x%x ispeed %u ospeed %u\n", name,
2162             t->c_iflag, t->c_oflag, t->c_cflag, t->c_lflag,
2163             t->c_ispeed, t->c_ospeed);
2164 }
2165
2166 /* DDB command to show TTY statistics. */
2167 DB_SHOW_COMMAND(tty, db_show_tty)
2168 {
2169         struct tty *tp;
2170
2171         if (!have_addr) {
2172                 db_printf("usage: show tty <addr>\n");
2173                 return;
2174         }
2175         tp = (struct tty *)addr;
2176
2177         db_printf("0x%p: %s\n", tp, tty_devname(tp));
2178         db_printf("\tmtx: %p\n", tp->t_mtx);
2179         db_printf("\tflags: %b\n", tp->t_flags, TTY_FLAG_BITS);
2180         db_printf("\trevokecnt: %u\n", tp->t_revokecnt);
2181
2182         /* Buffering mechanisms. */
2183         db_printf("\tinq: %p begin %u linestart %u reprint %u end %u "
2184             "nblocks %u quota %u\n", &tp->t_inq, tp->t_inq.ti_begin,
2185             tp->t_inq.ti_linestart, tp->t_inq.ti_reprint, tp->t_inq.ti_end,
2186             tp->t_inq.ti_nblocks, tp->t_inq.ti_quota);
2187         db_printf("\toutq: %p begin %u end %u nblocks %u quota %u\n",
2188             &tp->t_outq, tp->t_outq.to_begin, tp->t_outq.to_end,
2189             tp->t_outq.to_nblocks, tp->t_outq.to_quota);
2190         db_printf("\tinlow: %zu\n", tp->t_inlow);
2191         db_printf("\toutlow: %zu\n", tp->t_outlow);
2192         _db_show_termios("\ttermios", &tp->t_termios);
2193         db_printf("\twinsize: row %u col %u xpixel %u ypixel %u\n",
2194             tp->t_winsize.ws_row, tp->t_winsize.ws_col,
2195             tp->t_winsize.ws_xpixel, tp->t_winsize.ws_ypixel);
2196         db_printf("\tcolumn: %u\n", tp->t_column);
2197         db_printf("\twritepos: %u\n", tp->t_writepos);
2198         db_printf("\tcompatflags: 0x%x\n", tp->t_compatflags);
2199
2200         /* Init/lock-state devices. */
2201         _db_show_termios("\ttermios_init_in", &tp->t_termios_init_in);
2202         _db_show_termios("\ttermios_init_out", &tp->t_termios_init_out);
2203         _db_show_termios("\ttermios_lock_in", &tp->t_termios_lock_in);
2204         _db_show_termios("\ttermios_lock_out", &tp->t_termios_lock_out);
2205
2206         /* Hooks */
2207         _db_show_devsw("\t", tp->t_devsw);
2208         _db_show_hooks("\t", tp->t_hook);
2209
2210         /* Process info. */
2211         db_printf("\tpgrp: %p gid %d jobc %d\n", tp->t_pgrp,
2212             tp->t_pgrp ? tp->t_pgrp->pg_id : 0,
2213             tp->t_pgrp ? tp->t_pgrp->pg_jobc : 0);
2214         db_printf("\tsession: %p", tp->t_session);
2215         if (tp->t_session != NULL)
2216             db_printf(" count %u leader %p tty %p sid %d login %s",
2217                 tp->t_session->s_count, tp->t_session->s_leader,
2218                 tp->t_session->s_ttyp, tp->t_session->s_sid,
2219                 tp->t_session->s_login);
2220         db_printf("\n");
2221         db_printf("\tsessioncnt: %u\n", tp->t_sessioncnt);
2222         db_printf("\tdevswsoftc: %p\n", tp->t_devswsoftc);
2223         db_printf("\thooksoftc: %p\n", tp->t_hooksoftc);
2224         db_printf("\tdev: %p\n", tp->t_dev);
2225 }
2226
2227 /* DDB command to list TTYs. */
2228 DB_SHOW_ALL_COMMAND(ttys, db_show_all_ttys)
2229 {
2230         struct tty *tp;
2231         size_t isiz, osiz;
2232         int i, j;
2233
2234         /* Make the output look like `pstat -t'. */
2235         db_printf("PTR        ");
2236 #if defined(__LP64__)
2237         db_printf("        ");
2238 #endif
2239         db_printf("      LINE   INQ  CAN  LIN  LOW  OUTQ  USE  LOW   "
2240             "COL  SESS  PGID STATE\n");
2241
2242         TAILQ_FOREACH(tp, &tty_list, t_list) {
2243                 isiz = tp->t_inq.ti_nblocks * TTYINQ_DATASIZE;
2244                 osiz = tp->t_outq.to_nblocks * TTYOUTQ_DATASIZE;
2245
2246                 db_printf("%p %10s %5zu %4u %4u %4zu %5zu %4u %4zu %5u %5d %5d ",
2247                     tp,
2248                     tty_devname(tp),
2249                     isiz,
2250                     tp->t_inq.ti_linestart - tp->t_inq.ti_begin,
2251                     tp->t_inq.ti_end - tp->t_inq.ti_linestart,
2252                     isiz - tp->t_inlow,
2253                     osiz,
2254                     tp->t_outq.to_end - tp->t_outq.to_begin,
2255                     osiz - tp->t_outlow,
2256                     MIN(tp->t_column, 99999),
2257                     tp->t_session ? tp->t_session->s_sid : 0,
2258                     tp->t_pgrp ? tp->t_pgrp->pg_id : 0);
2259
2260                 /* Flag bits. */
2261                 for (i = j = 0; ttystates[i].flag; i++)
2262                         if (tp->t_flags & ttystates[i].flag) {
2263                                 db_printf("%c", ttystates[i].val);
2264                                 j++;
2265                         }
2266                 if (j == 0)
2267                         db_printf("-");
2268                 db_printf("\n");
2269         }
2270 }
2271 #endif /* DDB */