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/capability.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 ouput 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)
 127 {
 128         int error;
 129
 130         if (ttyhook_hashook(tp, getc_inject))
 131                 /* buffer is inaccessible */
 132                 return (0);
 133
 134         while (ttyoutq_bytesused(&tp->t_outq) > 0) {
 135                 ttydevsw_outwakeup(tp);
 136                 /* Could be handled synchronously. */
 137                 if (ttyoutq_bytesused(&tp->t_outq) == 0)
 138                         return (0);
 139
 140                 /* Wait for data to be drained. */
 141                 error = tty_wait(tp, &tp->t_outwait);
 142                 if (error)
 143                         return (error);
 144         }
 145
 146         return (0);
 147 }
 148
 149 /*
 150  * Though ttydev_enter() and ttydev_leave() seem to be related, they
 151  * don't have to be used together. ttydev_enter() is used by the cdev
 152  * operations to prevent an actual operation from being processed when
 153  * the TTY has been abandoned. ttydev_leave() is used by ttydev_open()
 154  * and ttydev_close() to determine whether per-TTY data should be
 155  * deallocated.
 156  */
 157
 158 static __inline int
 159 ttydev_enter(struct tty *tp)
 160 {
 161         tty_lock(tp);
 162
 163         if (tty_gone(tp) || !tty_opened(tp)) {
 164                 /* Device is already gone. */
 165                 tty_unlock(tp);
 166                 return (ENXIO);
 167         }
 168
 169         return (0);
 170 }
 171
 172 static void
 173 ttydev_leave(struct tty *tp)
 174 {
 175         tty_lock_assert(tp, MA_OWNED);
 176
 177         if (tty_opened(tp) || tp->t_flags & TF_OPENCLOSE) {
 178                 /* Device is still opened somewhere. */
 179                 tty_unlock(tp);
 180                 return;
 181         }
 182
 183         tp->t_flags |= TF_OPENCLOSE;
 184
 185         /* Stop asynchronous I/O. */
 186         funsetown(&tp->t_sigio);
 187
 188         /* Remove console TTY. */
 189         if (constty == tp)
 190                 constty_clear();
 191
 192         /* Drain any output. */
 193         MPASS((tp->t_flags & TF_STOPPED) == 0);
 194         if (!tty_gone(tp))
 195                 tty_drain(tp);
 196
 197         ttydisc_close(tp);
 198
 199         /* Destroy associated buffers already. */
 200         ttyinq_free(&tp->t_inq);
 201         tp->t_inlow = 0;
 202         ttyoutq_free(&tp->t_outq);
 203         tp->t_outlow = 0;
 204
 205         knlist_clear(&tp->t_inpoll.si_note, 1);
 206         knlist_clear(&tp->t_outpoll.si_note, 1);
 207
 208         if (!tty_gone(tp))
 209                 ttydevsw_close(tp);
 210
 211         tp->t_flags &= ~TF_OPENCLOSE;
 212         cv_broadcast(&tp->t_dcdwait);
 213         tty_rel_free(tp);
 214 }
 215
 216 /*
 217  * Operations that are exposed through the character device in /dev.
 218  */
 219 static int
 220 ttydev_open(struct cdev *dev, int oflags, int devtype, struct thread *td)
 221 {
 222         struct tty *tp;
 223         int error = 0;
 224
 225         while ((tp = dev->si_drv1) == NULL) {
 226                 error = tsleep(&dev->si_drv1, PCATCH, "ttdrv1", 1);
 227                 if (error != EWOULDBLOCK)
 228                         return (error);
 229         }
 230
 231         tty_lock(tp);
 232         if (tty_gone(tp)) {
 233                 /* Device is already gone. */
 234                 tty_unlock(tp);
 235                 return (ENXIO);
 236         }
 237
 238         /*
 239          * Block when other processes are currently opening or closing
 240          * the TTY.
 241          */
 242         while (tp->t_flags & TF_OPENCLOSE) {
 243                 error = tty_wait(tp, &tp->t_dcdwait);
 244                 if (error != 0) {
 245                         tty_unlock(tp);
 246                         return (error);
 247                 }
 248         }
 249         tp->t_flags |= TF_OPENCLOSE;
 250
 251         /*
 252          * Make sure the "tty" and "cua" device cannot be opened at the
 253          * same time.
 254          */
 255         if (TTY_CALLOUT(tp, dev)) {
 256                 if (tp->t_flags & TF_OPENED_IN) {
 257                         error = EBUSY;
 258                         goto done;
 259                 }
 260         } else {
 261                 if (tp->t_flags & TF_OPENED_OUT) {
 262                         error = EBUSY;
 263                         goto done;
 264                 }
 265         }
 266
 267         if (tp->t_flags & TF_EXCLUDE && priv_check(td, PRIV_TTY_EXCLUSIVE)) {
 268                 error = EBUSY;
 269                 goto done;
 270         }
 271
 272         if (!tty_opened(tp)) {
 273                 /* Set proper termios flags. */
 274                 if (TTY_CALLOUT(tp, dev))
 275                         tp->t_termios = tp->t_termios_init_out;
 276                 else
 277                         tp->t_termios = tp->t_termios_init_in;
 278                 ttydevsw_param(tp, &tp->t_termios);
 279                 /* Prevent modem control on callout devices and /dev/console. */
 280                 if (TTY_CALLOUT(tp, dev) || dev == dev_console)
 281                         tp->t_termios.c_cflag |= CLOCAL;
 282
 283                 ttydevsw_modem(tp, SER_DTR|SER_RTS, 0);
 284
 285                 error = ttydevsw_open(tp);
 286                 if (error != 0)
 287                         goto done;
 288
 289                 ttydisc_open(tp);
 290                 tty_watermarks(tp);
 291         }
 292
 293         /* Wait for Carrier Detect. */
 294         if ((oflags & O_NONBLOCK) == 0 &&
 295             (tp->t_termios.c_cflag & CLOCAL) == 0) {
 296                 while ((ttydevsw_modem(tp, 0, 0) & SER_DCD) == 0) {
 297                         error = tty_wait(tp, &tp->t_dcdwait);
 298                         if (error != 0)
 299                                 goto done;
 300                 }
 301         }
 302
 303         if (dev == dev_console)
 304                 tp->t_flags |= TF_OPENED_CONS;
 305         else if (TTY_CALLOUT(tp, dev))
 306                 tp->t_flags |= TF_OPENED_OUT;
 307         else
 308                 tp->t_flags |= TF_OPENED_IN;
 309
 310 done:   tp->t_flags &= ~TF_OPENCLOSE;
 311         cv_broadcast(&tp->t_dcdwait);
 312         ttydev_leave(tp);
 313
 314         return (error);
 315 }
 316
 317 static int
 318 ttydev_close(struct cdev *dev, int fflag, int devtype, struct thread *td)
 319 {
 320         struct tty *tp = dev->si_drv1;
 321
 322         tty_lock(tp);
 323
 324         /*
 325          * Don't actually close the device if it is being used as the
 326          * console.
 327          */
 328         MPASS((tp->t_flags & TF_OPENED) != TF_OPENED);
 329         if (dev == dev_console)
 330                 tp->t_flags &= ~TF_OPENED_CONS;
 331         else
 332                 tp->t_flags &= ~(TF_OPENED_IN|TF_OPENED_OUT);
 333
 334         if (tp->t_flags & TF_OPENED) {
 335                 tty_unlock(tp);
 336                 return (0);
 337         }
 338
 339         /*
 340          * This can only be called once. The callin and the callout
 341          * devices cannot be opened at the same time.
 342          */
 343         tp->t_flags &= ~(TF_EXCLUDE|TF_STOPPED);
 344
 345         /* Properly wake up threads that are stuck - revoke(). */
 346         tp->t_revokecnt++;
 347         tty_wakeup(tp, FREAD|FWRITE);
 348         cv_broadcast(&tp->t_bgwait);
 349         cv_broadcast(&tp->t_dcdwait);
 350
 351         ttydev_leave(tp);
 352
 353         return (0);
 354 }
 355
 356 static __inline int
 357 tty_is_ctty(struct tty *tp, struct proc *p)
 358 {
 359         tty_lock_assert(tp, MA_OWNED);
 360
 361         return (p->p_session == tp->t_session && p->p_flag & P_CONTROLT);
 362 }
 363
 364 static int
 365 tty_wait_background(struct tty *tp, struct thread *td, int sig)
 366 {
 367         struct proc *p = td->td_proc;
 368         struct pgrp *pg;
 369         ksiginfo_t ksi;
 370         int error;
 371
 372         MPASS(sig == SIGTTIN || sig == SIGTTOU);
 373         tty_lock_assert(tp, MA_OWNED);
 374
 375         for (;;) {
 376                 PROC_LOCK(p);
 377                 /*
 378                  * The process should only sleep, when:
 379                  * - This terminal is the controling terminal
 380                  * - Its process group is not the foreground process
 381                  *   group
 382                  * - The parent process isn't waiting for the child to
 383                  *   exit
 384                  * - the signal to send to the process isn't masked
 385                  */
 386                 if (!tty_is_ctty(tp, p) || p->p_pgrp == tp->t_pgrp) {
 387                         /* Allow the action to happen. */
 388                         PROC_UNLOCK(p);
 389                         return (0);
 390                 }
 391
 392                 if (SIGISMEMBER(p->p_sigacts->ps_sigignore, sig) ||
 393                     SIGISMEMBER(td->td_sigmask, sig)) {
 394                         /* Only allow them in write()/ioctl(). */
 395                         PROC_UNLOCK(p);
 396                         return (sig == SIGTTOU ? 0 : EIO);
 397                 }
 398
 399                 pg = p->p_pgrp;
 400                 if (p->p_flag & P_PPWAIT || pg->pg_jobc == 0) {
 401                         /* Don't allow the action to happen. */
 402                         PROC_UNLOCK(p);
 403                         return (EIO);
 404                 }
 405                 PROC_UNLOCK(p);
 406
 407                 /*
 408                  * Send the signal and sleep until we're the new
 409                  * foreground process group.
 410                  */
 411                 if (sig != 0) {
 412                         ksiginfo_init(&ksi);
 413                         ksi.ksi_code = SI_KERNEL;
 414                         ksi.ksi_signo = sig;
 415                         sig = 0;
 416                 }
 417                 PGRP_LOCK(pg);
 418                 pgsignal(pg, ksi.ksi_signo, 1, &ksi);
 419                 PGRP_UNLOCK(pg);
 420
 421                 error = tty_wait(tp, &tp->t_bgwait);
 422                 if (error)
 423                         return (error);
 424         }
 425 }
 426
 427 static int
 428 ttydev_read(struct cdev *dev, struct uio *uio, int ioflag)
 429 {
 430         struct tty *tp = dev->si_drv1;
 431         int error;
 432
 433         error = ttydev_enter(tp);
 434         if (error)
 435                 goto done;
 436
 437         error = tty_wait_background(tp, curthread, SIGTTIN);
 438         if (error) {
 439                 tty_unlock(tp);
 440                 goto done;
 441         }
 442
 443         error = ttydisc_read(tp, uio, ioflag);
 444         tty_unlock(tp);
 445
 446         /*
 447          * The read() call should not throw an error when the device is
 448          * being destroyed. Silently convert it to an EOF.
 449          */
 450 done:   if (error == ENXIO)
 451                 error = 0;
 452         return (error);
 453 }
 454
 455 static int
 456 ttydev_write(struct cdev *dev, struct uio *uio, int ioflag)
 457 {
 458         struct tty *tp = dev->si_drv1;
 459         int error;
 460
 461         error = ttydev_enter(tp);
 462         if (error)
 463                 return (error);
 464
 465         if (tp->t_termios.c_lflag & TOSTOP) {
 466                 error = tty_wait_background(tp, curthread, SIGTTOU);
 467                 if (error)
 468                         goto done;
 469         }
 470
 471         if (ioflag & IO_NDELAY && tp->t_flags & TF_BUSY_OUT) {
 472                 /* Allow non-blocking writes to bypass serialization. */
 473                 error = ttydisc_write(tp, uio, ioflag);
 474         } else {
 475                 /* Serialize write() calls. */
 476                 while (tp->t_flags & TF_BUSY_OUT) {
 477                         error = tty_wait(tp, &tp->t_outserwait);
 478                         if (error)
 479                                 goto done;
 480                 }
 481
 482                 tp->t_flags |= TF_BUSY_OUT;
 483                 error = ttydisc_write(tp, uio, ioflag);
 484                 tp->t_flags &= ~TF_BUSY_OUT;
 485                 cv_signal(&tp->t_outserwait);
 486         }
 487
 488 done:   tty_unlock(tp);
 489         return (error);
 490 }
 491
 492 static int
 493 ttydev_ioctl(struct cdev *dev, u_long cmd, caddr_t data, int fflag,
 494     struct thread *td)
 495 {
 496         struct tty *tp = dev->si_drv1;
 497         int error;
 498
 499         error = ttydev_enter(tp);
 500         if (error)
 501                 return (error);
 502
 503         switch (cmd) {
 504         case TIOCCBRK:
 505         case TIOCCONS:
 506         case TIOCDRAIN:
 507         case TIOCEXCL:
 508         case TIOCFLUSH:
 509         case TIOCNXCL:
 510         case TIOCSBRK:
 511         case TIOCSCTTY:
 512         case TIOCSETA:
 513         case TIOCSETAF:
 514         case TIOCSETAW:
 515         case TIOCSPGRP:
 516         case TIOCSTART:
 517         case TIOCSTAT:
 518         case TIOCSTI:
 519         case TIOCSTOP:
 520         case TIOCSWINSZ:
 521 #if 0
 522         case TIOCSDRAINWAIT:
 523         case TIOCSETD:
 524 #endif
 525 #ifdef COMPAT_43TTY
 526         case  TIOCLBIC:
 527         case  TIOCLBIS:
 528         case  TIOCLSET:
 529         case  TIOCSETC:
 530         case OTIOCSETD:
 531         case  TIOCSETN:
 532         case  TIOCSETP:
 533         case  TIOCSLTC:
 534 #endif /* COMPAT_43TTY */
 535                 /*
 536                  * If the ioctl() causes the TTY to be modified, let it
 537                  * wait in the background.
 538                  */
 539                 error = tty_wait_background(tp, curthread, SIGTTOU);
 540                 if (error)
 541                         goto done;
 542         }
 543
 544         if (cmd == TIOCSETA || cmd == TIOCSETAW || cmd == TIOCSETAF) {
 545                 struct termios *old = &tp->t_termios;
 546                 struct termios *new = (struct termios *)data;
 547                 struct termios *lock = TTY_CALLOUT(tp, dev) ?
 548                     &tp->t_termios_lock_out : &tp->t_termios_lock_in;
 549                 int cc;
 550
 551                 /*
 552                  * Lock state devices.  Just overwrite the values of the
 553                  * commands that are currently in use.
 554                  */
 555                 new->c_iflag = (old->c_iflag & lock->c_iflag) |
 556                     (new->c_iflag & ~lock->c_iflag);
 557                 new->c_oflag = (old->c_oflag & lock->c_oflag) |
 558                     (new->c_oflag & ~lock->c_oflag);
 559                 new->c_cflag = (old->c_cflag & lock->c_cflag) |
 560                     (new->c_cflag & ~lock->c_cflag);
 561                 new->c_lflag = (old->c_lflag & lock->c_lflag) |
 562                     (new->c_lflag & ~lock->c_lflag);
 563                 for (cc = 0; cc < NCCS; ++cc)
 564                         if (lock->c_cc[cc])
 565                                 new->c_cc[cc] = old->c_cc[cc];
 566                 if (lock->c_ispeed)
 567                         new->c_ispeed = old->c_ispeed;
 568                 if (lock->c_ospeed)
 569                         new->c_ospeed = old->c_ospeed;
 570         }
 571
 572         error = tty_ioctl(tp, cmd, data, fflag, td);
 573 done:   tty_unlock(tp);
 574
 575         return (error);
 576 }
 577
 578 static int
 579 ttydev_poll(struct cdev *dev, int events, struct thread *td)
 580 {
 581         struct tty *tp = dev->si_drv1;
 582         int error, revents = 0;
 583
 584         error = ttydev_enter(tp);
 585         if (error)
 586                 return ((events & (POLLIN|POLLRDNORM)) | POLLHUP);
 587
 588         if (events & (POLLIN|POLLRDNORM)) {
 589                 /* See if we can read something. */
 590                 if (ttydisc_read_poll(tp) > 0)
 591                         revents |= events & (POLLIN|POLLRDNORM);
 592         }
 593
 594         if (tp->t_flags & TF_ZOMBIE) {
 595                 /* Hangup flag on zombie state. */
 596                 revents |= POLLHUP;
 597         } else if (events & (POLLOUT|POLLWRNORM)) {
 598                 /* See if we can write something. */
 599                 if (ttydisc_write_poll(tp) > 0)
 600                         revents |= events & (POLLOUT|POLLWRNORM);
 601         }
 602
 603         if (revents == 0) {
 604                 if (events & (POLLIN|POLLRDNORM))
 605                         selrecord(td, &tp->t_inpoll);
 606                 if (events & (POLLOUT|POLLWRNORM))
 607                         selrecord(td, &tp->t_outpoll);
 608         }
 609
 610         tty_unlock(tp);
 611
 612         return (revents);
 613 }
 614
 615 static int
 616 ttydev_mmap(struct cdev *dev, vm_ooffset_t offset, vm_paddr_t *paddr,
 617     int nprot, vm_memattr_t *memattr)
 618 {
 619         struct tty *tp = dev->si_drv1;
 620         int error;
 621
 622         /* Handle mmap() through the driver. */
 623
 624         error = ttydev_enter(tp);
 625         if (error)
 626                 return (-1);
 627         error = ttydevsw_mmap(tp, offset, paddr, nprot, memattr);
 628         tty_unlock(tp);
 629
 630         return (error);
 631 }
 632
 633 /*
 634  * kqueue support.
 635  */
 636
 637 static void
 638 tty_kqops_read_detach(struct knote *kn)
 639 {
 640         struct tty *tp = kn->kn_hook;
 641
 642         knlist_remove(&tp->t_inpoll.si_note, kn, 0);
 643 }
 644
 645 static int
 646 tty_kqops_read_event(struct knote *kn, long hint)
 647 {
 648         struct tty *tp = kn->kn_hook;
 649
 650         tty_lock_assert(tp, MA_OWNED);
 651
 652         if (tty_gone(tp) || tp->t_flags & TF_ZOMBIE) {
 653                 kn->kn_flags |= EV_EOF;
 654                 return (1);
 655         } else {
 656                 kn->kn_data = ttydisc_read_poll(tp);
 657                 return (kn->kn_data > 0);
 658         }
 659 }
 660
 661 static void
 662 tty_kqops_write_detach(struct knote *kn)
 663 {
 664         struct tty *tp = kn->kn_hook;
 665
 666         knlist_remove(&tp->t_outpoll.si_note, kn, 0);
 667 }
 668
 669 static int
 670 tty_kqops_write_event(struct knote *kn, long hint)
 671 {
 672         struct tty *tp = kn->kn_hook;
 673
 674         tty_lock_assert(tp, MA_OWNED);
 675
 676         if (tty_gone(tp)) {
 677                 kn->kn_flags |= EV_EOF;
 678                 return (1);
 679         } else {
 680                 kn->kn_data = ttydisc_write_poll(tp);
 681                 return (kn->kn_data > 0);
 682         }
 683 }
 684
 685 static struct filterops tty_kqops_read = {
 686         .f_isfd = 1,
 687         .f_detach = tty_kqops_read_detach,
 688         .f_event = tty_kqops_read_event,
 689 };
 690 static struct filterops tty_kqops_write = {
 691         .f_isfd = 1,
 692         .f_detach = tty_kqops_write_detach,
 693         .f_event = tty_kqops_write_event,
 694 };
 695
 696 static int
 697 ttydev_kqfilter(struct cdev *dev, struct knote *kn)
 698 {
 699         struct tty *tp = dev->si_drv1;
 700         int error;
 701
 702         error = ttydev_enter(tp);
 703         if (error)
 704                 return (error);
 705
 706         switch (kn->kn_filter) {
 707         case EVFILT_READ:
 708                 kn->kn_hook = tp;
 709                 kn->kn_fop = &tty_kqops_read;
 710                 knlist_add(&tp->t_inpoll.si_note, kn, 1);
 711                 break;
 712         case EVFILT_WRITE:
 713                 kn->kn_hook = tp;
 714                 kn->kn_fop = &tty_kqops_write;
 715                 knlist_add(&tp->t_outpoll.si_note, kn, 1);
 716                 break;
 717         default:
 718                 error = EINVAL;
 719                 break;
 720         }
 721
 722         tty_unlock(tp);
 723         return (error);
 724 }
 725
 726 static struct cdevsw ttydev_cdevsw = {
 727         .d_version      = D_VERSION,
 728         .d_open         = ttydev_open,
 729         .d_close        = ttydev_close,
 730         .d_read         = ttydev_read,
 731         .d_write        = ttydev_write,
 732         .d_ioctl        = ttydev_ioctl,
 733         .d_kqfilter     = ttydev_kqfilter,
 734         .d_poll         = ttydev_poll,
 735         .d_mmap         = ttydev_mmap,
 736         .d_name         = "ttydev",
 737         .d_flags        = D_TTY,
 738 };
 739
 740 /*
 741  * Init/lock-state devices
 742  */
 743
 744 static int
 745 ttyil_open(struct cdev *dev, int oflags, int devtype, struct thread *td)
 746 {
 747         struct tty *tp;
 748         int error = 0;
 749
 750         while ((tp = dev->si_drv1) == NULL) {
 751                 error = tsleep(&dev->si_drv1, PCATCH, "ttdrv1", 1);
 752                 if (error != EWOULDBLOCK)
 753                         return (error);
 754         }
 755         tty_lock(tp);
 756         if (tty_gone(tp))
 757                 error = ENODEV;
 758         tty_unlock(tp);
 759
 760         return (error);
 761 }
 762
 763 static int
 764 ttyil_close(struct cdev *dev, int flag, int mode, struct thread *td)
 765 {
 766         return (0);
 767 }
 768
 769 static int
 770 ttyil_rdwr(struct cdev *dev, struct uio *uio, int ioflag)
 771 {
 772         return (ENODEV);
 773 }
 774
 775 static int
 776 ttyil_ioctl(struct cdev *dev, u_long cmd, caddr_t data, int fflag,
 777     struct thread *td)
 778 {
 779         struct tty *tp = dev->si_drv1;
 780         int error;
 781
 782         tty_lock(tp);
 783         if (tty_gone(tp)) {
 784                 error = ENODEV;
 785                 goto done;
 786         }
 787
 788         error = ttydevsw_cioctl(tp, dev2unit(dev), cmd, data, td);
 789         if (error != ENOIOCTL)
 790                 goto done;
 791         error = 0;
 792
 793         switch (cmd) {
 794         case TIOCGETA:
 795                 /* Obtain terminal flags through tcgetattr(). */
 796                 *(struct termios*)data = *(struct termios*)dev->si_drv2;
 797                 break;
 798         case TIOCSETA:
 799                 /* Set terminal flags through tcsetattr(). */
 800                 error = priv_check(td, PRIV_TTY_SETA);
 801                 if (error)
 802                         break;
 803                 *(struct termios*)dev->si_drv2 = *(struct termios*)data;
 804                 break;
 805         case TIOCGETD:
 806                 *(int *)data = TTYDISC;
 807                 break;
 808         case TIOCGWINSZ:
 809                 bzero(data, sizeof(struct winsize));
 810                 break;
 811         default:
 812                 error = ENOTTY;
 813         }
 814
 815 done:   tty_unlock(tp);
 816         return (error);
 817 }
 818
 819 static struct cdevsw ttyil_cdevsw = {
 820         .d_version      = D_VERSION,
 821         .d_open         = ttyil_open,
 822         .d_close        = ttyil_close,
 823         .d_read         = ttyil_rdwr,
 824         .d_write        = ttyil_rdwr,
 825         .d_ioctl        = ttyil_ioctl,
 826         .d_name         = "ttyil",
 827         .d_flags        = D_TTY,
 828 };
 829
 830 static void
 831 tty_init_termios(struct tty *tp)
 832 {
 833         struct termios *t = &tp->t_termios_init_in;
 834
 835         t->c_cflag = TTYDEF_CFLAG;
 836         t->c_iflag = TTYDEF_IFLAG;
 837         t->c_lflag = TTYDEF_LFLAG;
 838         t->c_oflag = TTYDEF_OFLAG;
 839         t->c_ispeed = TTYDEF_SPEED;
 840         t->c_ospeed = TTYDEF_SPEED;
 841         memcpy(&t->c_cc, ttydefchars, sizeof ttydefchars);
 842
 843         tp->t_termios_init_out = *t;
 844 }
 845
 846 void
 847 tty_init_console(struct tty *tp, speed_t s)
 848 {
 849         struct termios *ti = &tp->t_termios_init_in;
 850         struct termios *to = &tp->t_termios_init_out;
 851
 852         if (s != 0) {
 853                 ti->c_ispeed = ti->c_ospeed = s;
 854                 to->c_ispeed = to->c_ospeed = s;
 855         }
 856
 857         ti->c_cflag |= CLOCAL;
 858         to->c_cflag |= CLOCAL;
 859 }
 860
 861 /*
 862  * Standard device routine implementations, mostly meant for
 863  * pseudo-terminal device drivers. When a driver creates a new terminal
 864  * device class, missing routines are patched.
 865  */
 866
 867 static int
 868 ttydevsw_defopen(struct tty *tp)
 869 {
 870
 871         return (0);
 872 }
 873
 874 static void
 875 ttydevsw_defclose(struct tty *tp)
 876 {
 877 }
 878
 879 static void
 880 ttydevsw_defoutwakeup(struct tty *tp)
 881 {
 882
 883         panic("Terminal device has output, while not implemented");
 884 }
 885
 886 static void
 887 ttydevsw_definwakeup(struct tty *tp)
 888 {
 889 }
 890
 891 static int
 892 ttydevsw_defioctl(struct tty *tp, u_long cmd, caddr_t data, struct thread *td)
 893 {
 894
 895         return (ENOIOCTL);
 896 }
 897
 898 static int
 899 ttydevsw_defcioctl(struct tty *tp, int unit, u_long cmd, caddr_t data, struct thread *td)
 900 {
 901
 902         return (ENOIOCTL);
 903 }
 904
 905 static int
 906 ttydevsw_defparam(struct tty *tp, struct termios *t)
 907 {
 908
 909         /*
 910          * Allow the baud rate to be adjusted for pseudo-devices, but at
 911          * least restrict it to 115200 to prevent excessive buffer
 912          * usage.  Also disallow 0, to prevent foot shooting.
 913          */
 914         if (t->c_ispeed < B50)
 915                 t->c_ispeed = B50;
 916         else if (t->c_ispeed > B115200)
 917                 t->c_ispeed = B115200;
 918         if (t->c_ospeed < B50)
 919                 t->c_ospeed = B50;
 920         else if (t->c_ospeed > B115200)
 921                 t->c_ospeed = B115200;
 922         t->c_cflag |= CREAD;
 923
 924         return (0);
 925 }
 926
 927 static int
 928 ttydevsw_defmodem(struct tty *tp, int sigon, int sigoff)
 929 {
 930
 931         /* Simulate a carrier to make the TTY layer happy. */
 932         return (SER_DCD);
 933 }
 934
 935 static int
 936 ttydevsw_defmmap(struct tty *tp, vm_ooffset_t offset, vm_paddr_t *paddr,
 937     int nprot, vm_memattr_t *memattr)
 938 {
 939
 940         return (-1);
 941 }
 942
 943 static void
 944 ttydevsw_defpktnotify(struct tty *tp, char event)
 945 {
 946 }
 947
 948 static void
 949 ttydevsw_deffree(void *softc)
 950 {
 951
 952         panic("Terminal device freed without a free-handler");
 953 }
 954
 955 /*
 956  * TTY allocation and deallocation. TTY devices can be deallocated when
 957  * the driver doesn't use it anymore, when the TTY isn't a session's
 958  * controlling TTY and when the device node isn't opened through devfs.
 959  */
 960
 961 struct tty *
 962 tty_alloc(struct ttydevsw *tsw, void *sc)
 963 {
 964
 965         return (tty_alloc_mutex(tsw, sc, NULL));
 966 }
 967
 968 struct tty *
 969 tty_alloc_mutex(struct ttydevsw *tsw, void *sc, struct mtx *mutex)
 970 {
 971         struct tty *tp;
 972
 973         /* Make sure the driver defines all routines. */
 974 #define PATCH_FUNC(x) do {                              \
 975         if (tsw->tsw_ ## x == NULL)                     \
 976                 tsw->tsw_ ## x = ttydevsw_def ## x;     \
 977 } while (0)
 978         PATCH_FUNC(open);
 979         PATCH_FUNC(close);
 980         PATCH_FUNC(outwakeup);
 981         PATCH_FUNC(inwakeup);
 982         PATCH_FUNC(ioctl);
 983         PATCH_FUNC(cioctl);
 984         PATCH_FUNC(param);
 985         PATCH_FUNC(modem);
 986         PATCH_FUNC(mmap);
 987         PATCH_FUNC(pktnotify);
 988         PATCH_FUNC(free);
 989 #undef PATCH_FUNC
 990
 991         tp = malloc(sizeof(struct tty), M_TTY, M_WAITOK|M_ZERO);
 992         tp->t_devsw = tsw;
 993         tp->t_devswsoftc = sc;
 994         tp->t_flags = tsw->tsw_flags;
 995
 996         tty_init_termios(tp);
 997
 998         cv_init(&tp->t_inwait, "ttyin");
 999         cv_init(&tp->t_outwait, "ttyout");
1000         cv_init(&tp->t_outserwait, "ttyosr");
1001         cv_init(&tp->t_bgwait, "ttybg");
1002         cv_init(&tp->t_dcdwait, "ttydcd");
1003
1004         /* Allow drivers to use a custom mutex to lock the TTY. */
1005         if (mutex != NULL) {
1006                 tp->t_mtx = mutex;
1007         } else {
1008                 tp->t_mtx = &tp->t_mtxobj;
1009                 mtx_init(&tp->t_mtxobj, "ttymtx", NULL, MTX_DEF);
1010         }
1011
1012         knlist_init_mtx(&tp->t_inpoll.si_note, tp->t_mtx);
1013         knlist_init_mtx(&tp->t_outpoll.si_note, tp->t_mtx);
1014
1015         sx_xlock(&tty_list_sx);
1016         TAILQ_INSERT_TAIL(&tty_list, tp, t_list);
1017         tty_list_count++;
1018         sx_xunlock(&tty_list_sx);
1019
1020         return (tp);
1021 }
1022
1023 static void
1024 tty_dealloc(void *arg)
1025 {
1026         struct tty *tp = arg;
1027
1028         sx_xlock(&tty_list_sx);
1029         TAILQ_REMOVE(&tty_list, tp, t_list);
1030         tty_list_count--;
1031         sx_xunlock(&tty_list_sx);
1032
1033         /* Make sure we haven't leaked buffers. */
1034         MPASS(ttyinq_getsize(&tp->t_inq) == 0);
1035         MPASS(ttyoutq_getsize(&tp->t_outq) == 0);
1036
1037         seldrain(&tp->t_inpoll);
1038         seldrain(&tp->t_outpoll);
1039         knlist_destroy(&tp->t_inpoll.si_note);
1040         knlist_destroy(&tp->t_outpoll.si_note);
1041
1042         cv_destroy(&tp->t_inwait);
1043         cv_destroy(&tp->t_outwait);
1044         cv_destroy(&tp->t_bgwait);
1045         cv_destroy(&tp->t_dcdwait);
1046         cv_destroy(&tp->t_outserwait);
1047
1048         if (tp->t_mtx == &tp->t_mtxobj)
1049                 mtx_destroy(&tp->t_mtxobj);
1050         ttydevsw_free(tp);
1051         free(tp, M_TTY);
1052 }
1053
1054 static void
1055 tty_rel_free(struct tty *tp)
1056 {
1057         struct cdev *dev;
1058
1059         tty_lock_assert(tp, MA_OWNED);
1060
1061 #define TF_ACTIVITY     (TF_GONE|TF_OPENED|TF_HOOK|TF_OPENCLOSE)
1062         if (tp->t_sessioncnt != 0 || (tp->t_flags & TF_ACTIVITY) != TF_GONE) {
1063                 /* TTY is still in use. */
1064                 tty_unlock(tp);
1065                 return;
1066         }
1067
1068         /* TTY can be deallocated. */
1069         dev = tp->t_dev;
1070         tp->t_dev = NULL;
1071         tty_unlock(tp);
1072
1073         if (dev != NULL)
1074                 destroy_dev_sched_cb(dev, tty_dealloc, tp);
1075 }
1076
1077 void
1078 tty_rel_pgrp(struct tty *tp, struct pgrp *pg)
1079 {
1080         MPASS(tp->t_sessioncnt > 0);
1081         tty_lock_assert(tp, MA_OWNED);
1082
1083         if (tp->t_pgrp == pg)
1084                 tp->t_pgrp = NULL;
1085
1086         tty_unlock(tp);
1087 }
1088
1089 void
1090 tty_rel_sess(struct tty *tp, struct session *sess)
1091 {
1092         MPASS(tp->t_sessioncnt > 0);
1093
1094         /* Current session has left. */
1095         if (tp->t_session == sess) {
1096                 tp->t_session = NULL;
1097                 MPASS(tp->t_pgrp == NULL);
1098         }
1099         tp->t_sessioncnt--;
1100         tty_rel_free(tp);
1101 }
1102
1103 void
1104 tty_rel_gone(struct tty *tp)
1105 {
1106         MPASS(!tty_gone(tp));
1107
1108         /* Simulate carrier removal. */
1109         ttydisc_modem(tp, 0);
1110
1111         /* Wake up all blocked threads. */
1112         tty_wakeup(tp, FREAD|FWRITE);
1113         cv_broadcast(&tp->t_bgwait);
1114         cv_broadcast(&tp->t_dcdwait);
1115
1116         tp->t_flags |= TF_GONE;
1117         tty_rel_free(tp);
1118 }
1119
1120 /*
1121  * Exposing information about current TTY's through sysctl
1122  */
1123
1124 static void
1125 tty_to_xtty(struct tty *tp, struct xtty *xt)
1126 {
1127         tty_lock_assert(tp, MA_OWNED);
1128
1129         xt->xt_size = sizeof(struct xtty);
1130         xt->xt_insize = ttyinq_getsize(&tp->t_inq);
1131         xt->xt_incc = ttyinq_bytescanonicalized(&tp->t_inq);
1132         xt->xt_inlc = ttyinq_bytesline(&tp->t_inq);
1133         xt->xt_inlow = tp->t_inlow;
1134         xt->xt_outsize = ttyoutq_getsize(&tp->t_outq);
1135         xt->xt_outcc = ttyoutq_bytesused(&tp->t_outq);
1136         xt->xt_outlow = tp->t_outlow;
1137         xt->xt_column = tp->t_column;
1138         xt->xt_pgid = tp->t_pgrp ? tp->t_pgrp->pg_id : 0;
1139         xt->xt_sid = tp->t_session ? tp->t_session->s_sid : 0;
1140         xt->xt_flags = tp->t_flags;
1141         xt->xt_dev = tp->t_dev ? dev2udev(tp->t_dev) : NODEV;
1142 }
1143
1144 static int
1145 sysctl_kern_ttys(SYSCTL_HANDLER_ARGS)
1146 {
1147         unsigned long lsize;
1148         struct xtty *xtlist, *xt;
1149         struct tty *tp;
1150         int error;
1151
1152         sx_slock(&tty_list_sx);
1153         lsize = tty_list_count * sizeof(struct xtty);
1154         if (lsize == 0) {
1155                 sx_sunlock(&tty_list_sx);
1156                 return (0);
1157         }
1158
1159         xtlist = xt = malloc(lsize, M_TTY, M_WAITOK);
1160
1161         TAILQ_FOREACH(tp, &tty_list, t_list) {
1162                 tty_lock(tp);
1163                 tty_to_xtty(tp, xt);
1164                 tty_unlock(tp);
1165                 xt++;
1166         }
1167         sx_sunlock(&tty_list_sx);
1168
1169         error = SYSCTL_OUT(req, xtlist, lsize);
1170         free(xtlist, M_TTY);
1171         return (error);
1172 }
1173
1174 SYSCTL_PROC(_kern, OID_AUTO, ttys, CTLTYPE_OPAQUE|CTLFLAG_RD|CTLFLAG_MPSAFE,
1175         0, 0, sysctl_kern_ttys, "S,xtty", "List of TTYs");
1176
1177 /*
1178  * Device node creation. Device has been set up, now we can expose it to
1179  * the user.
1180  */
1181
1182 void
1183 tty_makedev(struct tty *tp, struct ucred *cred, const char *fmt, ...)
1184 {
1185         va_list ap;
1186         struct cdev *dev;
1187         const char *prefix = "tty";
1188         char name[SPECNAMELEN - 3]; /* for "tty" and "cua". */
1189         uid_t uid;
1190         gid_t gid;
1191         mode_t mode;
1192
1193         /* Remove "tty" prefix from devices like PTY's. */
1194         if (tp->t_flags & TF_NOPREFIX)
1195                 prefix = "";
1196
1197         va_start(ap, fmt);
1198         vsnrprintf(name, sizeof name, 32, fmt, ap);
1199         va_end(ap);
1200
1201         if (cred == NULL) {
1202                 /* System device. */
1203                 uid = UID_ROOT;
1204                 gid = GID_WHEEL;
1205                 mode = S_IRUSR|S_IWUSR;
1206         } else {
1207                 /* User device. */
1208                 uid = cred->cr_ruid;
1209                 gid = GID_TTY;
1210                 mode = S_IRUSR|S_IWUSR|S_IWGRP;
1211         }
1212
1213         /* Master call-in device. */
1214         dev = make_dev_cred(&ttydev_cdevsw, 0, cred,
1215             uid, gid, mode, "%s%s", prefix, name);
1216         dev->si_drv1 = tp;
1217         wakeup(&dev->si_drv1);
1218         tp->t_dev = dev;
1219
1220         /* Slave call-in devices. */
1221         if (tp->t_flags & TF_INITLOCK) {
1222                 dev = make_dev_cred(&ttyil_cdevsw, TTYUNIT_INIT, cred,
1223                     uid, gid, mode, "%s%s.init", prefix, name);
1224                 dev_depends(tp->t_dev, dev);
1225                 dev->si_drv1 = tp;
1226                 wakeup(&dev->si_drv1);
1227                 dev->si_drv2 = &tp->t_termios_init_in;
1228
1229                 dev = make_dev_cred(&ttyil_cdevsw, TTYUNIT_LOCK, cred,
1230                     uid, gid, mode, "%s%s.lock", prefix, name);
1231                 dev_depends(tp->t_dev, dev);
1232                 dev->si_drv1 = tp;
1233                 wakeup(&dev->si_drv1);
1234                 dev->si_drv2 = &tp->t_termios_lock_in;
1235         }
1236
1237         /* Call-out devices. */
1238         if (tp->t_flags & TF_CALLOUT) {
1239                 dev = make_dev_cred(&ttydev_cdevsw, TTYUNIT_CALLOUT, cred,
1240                     UID_UUCP, GID_DIALER, 0660, "cua%s", name);
1241                 dev_depends(tp->t_dev, dev);
1242                 dev->si_drv1 = tp;
1243                 wakeup(&dev->si_drv1);
1244
1245                 /* Slave call-out devices. */
1246                 if (tp->t_flags & TF_INITLOCK) {
1247                         dev = make_dev_cred(&ttyil_cdevsw,
1248                             TTYUNIT_CALLOUT | TTYUNIT_INIT, cred,
1249                             UID_UUCP, GID_DIALER, 0660, "cua%s.init", name);
1250                         dev_depends(tp->t_dev, dev);
1251                         dev->si_drv1 = tp;
1252                         wakeup(&dev->si_drv1);
1253                         dev->si_drv2 = &tp->t_termios_init_out;
1254
1255                         dev = make_dev_cred(&ttyil_cdevsw,
1256                             TTYUNIT_CALLOUT | TTYUNIT_LOCK, cred,
1257                             UID_UUCP, GID_DIALER, 0660, "cua%s.lock", name);
1258                         dev_depends(tp->t_dev, dev);
1259                         dev->si_drv1 = tp;
1260                         wakeup(&dev->si_drv1);
1261                         dev->si_drv2 = &tp->t_termios_lock_out;
1262                 }
1263         }
1264 }
1265
1266 /*
1267  * Signalling processes.
1268  */
1269
1270 void
1271 tty_signal_sessleader(struct tty *tp, int sig)
1272 {
1273         struct proc *p;
1274
1275         tty_lock_assert(tp, MA_OWNED);
1276         MPASS(sig >= 1 && sig < NSIG);
1277
1278         /* Make signals start output again. */
1279         tp->t_flags &= ~TF_STOPPED;
1280
1281         if (tp->t_session != NULL && tp->t_session->s_leader != NULL) {
1282                 p = tp->t_session->s_leader;
1283                 PROC_LOCK(p);
1284                 kern_psignal(p, sig);
1285                 PROC_UNLOCK(p);
1286         }
1287 }
1288
1289 void
1290 tty_signal_pgrp(struct tty *tp, int sig)
1291 {
1292         ksiginfo_t ksi;
1293
1294         tty_lock_assert(tp, MA_OWNED);
1295         MPASS(sig >= 1 && sig < NSIG);
1296
1297         /* Make signals start output again. */
1298         tp->t_flags &= ~TF_STOPPED;
1299
1300         if (sig == SIGINFO && !(tp->t_termios.c_lflag & NOKERNINFO))
1301                 tty_info(tp);
1302         if (tp->t_pgrp != NULL) {
1303                 ksiginfo_init(&ksi);
1304                 ksi.ksi_signo = sig;
1305                 ksi.ksi_code = SI_KERNEL;
1306                 PGRP_LOCK(tp->t_pgrp);
1307                 pgsignal(tp->t_pgrp, sig, 1, &ksi);
1308                 PGRP_UNLOCK(tp->t_pgrp);
1309         }
1310 }
1311
1312 void
1313 tty_wakeup(struct tty *tp, int flags)
1314 {
1315         if (tp->t_flags & TF_ASYNC && tp->t_sigio != NULL)
1316                 pgsigio(&tp->t_sigio, SIGIO, (tp->t_session != NULL));
1317
1318         if (flags & FWRITE) {
1319                 cv_broadcast(&tp->t_outwait);
1320                 selwakeup(&tp->t_outpoll);
1321                 KNOTE_LOCKED(&tp->t_outpoll.si_note, 0);
1322         }
1323         if (flags & FREAD) {
1324                 cv_broadcast(&tp->t_inwait);
1325                 selwakeup(&tp->t_inpoll);
1326                 KNOTE_LOCKED(&tp->t_inpoll.si_note, 0);
1327         }
1328 }
1329
1330 int
1331 tty_wait(struct tty *tp, struct cv *cv)
1332 {
1333         int error;
1334         int revokecnt = tp->t_revokecnt;
1335
1336         tty_lock_assert(tp, MA_OWNED|MA_NOTRECURSED);
1337         MPASS(!tty_gone(tp));
1338
1339         error = cv_wait_sig(cv, tp->t_mtx);
1340
1341         /* Restart the system call when we may have been revoked. */
1342         if (tp->t_revokecnt != revokecnt)
1343                 return (ERESTART);
1344
1345         /* Bail out when the device slipped away. */
1346         if (tty_gone(tp))
1347                 return (ENXIO);
1348
1349         return (error);
1350 }
1351
1352 int
1353 tty_timedwait(struct tty *tp, struct cv *cv, int hz)
1354 {
1355         int error;
1356         int revokecnt = tp->t_revokecnt;
1357
1358         tty_lock_assert(tp, MA_OWNED|MA_NOTRECURSED);
1359         MPASS(!tty_gone(tp));
1360
1361         error = cv_timedwait_sig(cv, tp->t_mtx, hz);
1362
1363         /* Restart the system call when we may have been revoked. */
1364         if (tp->t_revokecnt != revokecnt)
1365                 return (ERESTART);
1366
1367         /* Bail out when the device slipped away. */
1368         if (tty_gone(tp))
1369                 return (ENXIO);
1370
1371         return (error);
1372 }
1373
1374 void
1375 tty_flush(struct tty *tp, int flags)
1376 {
1377         if (flags & FWRITE) {
1378                 tp->t_flags &= ~TF_HIWAT_OUT;
1379                 ttyoutq_flush(&tp->t_outq);
1380                 tty_wakeup(tp, FWRITE);
1381                 ttydevsw_pktnotify(tp, TIOCPKT_FLUSHWRITE);
1382         }
1383         if (flags & FREAD) {
1384                 tty_hiwat_in_unblock(tp);
1385                 ttyinq_flush(&tp->t_inq);
1386                 ttydevsw_inwakeup(tp);
1387                 ttydevsw_pktnotify(tp, TIOCPKT_FLUSHREAD);
1388         }
1389 }
1390
1391 static int
1392 tty_generic_ioctl(struct tty *tp, u_long cmd, void *data, int fflag,
1393     struct thread *td)
1394 {
1395         int error;
1396
1397         switch (cmd) {
1398         /*
1399          * Modem commands.
1400          * The SER_* and TIOCM_* flags are the same, but one bit
1401          * shifted. I don't know why.
1402          */
1403         case TIOCSDTR:
1404                 ttydevsw_modem(tp, SER_DTR, 0);
1405                 return (0);
1406         case TIOCCDTR:
1407                 ttydevsw_modem(tp, 0, SER_DTR);
1408                 return (0);
1409         case TIOCMSET: {
1410                 int bits = *(int *)data;
1411                 ttydevsw_modem(tp,
1412                     (bits & (TIOCM_DTR | TIOCM_RTS)) >> 1,
1413                     ((~bits) & (TIOCM_DTR | TIOCM_RTS)) >> 1);
1414                 return (0);
1415         }
1416         case TIOCMBIS: {
1417                 int bits = *(int *)data;
1418                 ttydevsw_modem(tp, (bits & (TIOCM_DTR | TIOCM_RTS)) >> 1, 0);
1419                 return (0);
1420         }
1421         case TIOCMBIC: {
1422                 int bits = *(int *)data;
1423                 ttydevsw_modem(tp, 0, (bits & (TIOCM_DTR | TIOCM_RTS)) >> 1);
1424                 return (0);
1425         }
1426         case TIOCMGET:
1427                 *(int *)data = TIOCM_LE + (ttydevsw_modem(tp, 0, 0) << 1);
1428                 return (0);
1429
1430         case FIOASYNC:
1431                 if (*(int *)data)
1432                         tp->t_flags |= TF_ASYNC;
1433                 else
1434                         tp->t_flags &= ~TF_ASYNC;
1435                 return (0);
1436         case FIONBIO:
1437                 /* This device supports non-blocking operation. */
1438                 return (0);
1439         case FIONREAD:
1440                 *(int *)data = ttyinq_bytescanonicalized(&tp->t_inq);
1441                 return (0);
1442         case FIONWRITE:
1443         case TIOCOUTQ:
1444                 *(int *)data = ttyoutq_bytesused(&tp->t_outq);
1445                 return (0);
1446         case FIOSETOWN:
1447                 if (tp->t_session != NULL && !tty_is_ctty(tp, td->td_proc))
1448                         /* Not allowed to set ownership. */
1449                         return (ENOTTY);
1450
1451                 /* Temporarily unlock the TTY to set ownership. */
1452                 tty_unlock(tp);
1453                 error = fsetown(*(int *)data, &tp->t_sigio);
1454                 tty_lock(tp);
1455                 return (error);
1456         case FIOGETOWN:
1457                 if (tp->t_session != NULL && !tty_is_ctty(tp, td->td_proc))
1458                         /* Not allowed to set ownership. */
1459                         return (ENOTTY);
1460
1461                 /* Get ownership. */
1462                 *(int *)data = fgetown(&tp->t_sigio);
1463                 return (0);
1464         case TIOCGETA:
1465                 /* Obtain terminal flags through tcgetattr(). */
1466                 *(struct termios*)data = tp->t_termios;
1467                 return (0);
1468         case TIOCSETA:
1469         case TIOCSETAW:
1470         case TIOCSETAF: {
1471                 struct termios *t = data;
1472
1473                 /*
1474                  * Who makes up these funny rules? According to POSIX,
1475                  * input baud rate is set equal to the output baud rate
1476                  * when zero.
1477                  */
1478                 if (t->c_ispeed == 0)
1479                         t->c_ispeed = t->c_ospeed;
1480
1481                 /* Discard any unsupported bits. */
1482                 t->c_iflag &= TTYSUP_IFLAG;
1483                 t->c_oflag &= TTYSUP_OFLAG;
1484                 t->c_lflag &= TTYSUP_LFLAG;
1485                 t->c_cflag &= TTYSUP_CFLAG;
1486
1487                 /* Set terminal flags through tcsetattr(). */
1488                 if (cmd == TIOCSETAW || cmd == TIOCSETAF) {
1489                         error = tty_drain(tp);
1490                         if (error)
1491                                 return (error);
1492                         if (cmd == TIOCSETAF)
1493                                 tty_flush(tp, FREAD);
1494                 }
1495
1496                 /*
1497                  * Only call param() when the flags really change.
1498                  */
1499                 if ((t->c_cflag & CIGNORE) == 0 &&
1500                     (tp->t_termios.c_cflag != t->c_cflag ||
1501                     ((tp->t_termios.c_iflag ^ t->c_iflag) &
1502                     (IXON|IXOFF|IXANY)) ||
1503                     tp->t_termios.c_ispeed != t->c_ispeed ||
1504                     tp->t_termios.c_ospeed != t->c_ospeed)) {
1505                         error = ttydevsw_param(tp, t);
1506                         if (error)
1507                                 return (error);
1508
1509                         /* XXX: CLOCAL? */
1510
1511                         tp->t_termios.c_cflag = t->c_cflag & ~CIGNORE;
1512                         tp->t_termios.c_ispeed = t->c_ispeed;
1513                         tp->t_termios.c_ospeed = t->c_ospeed;
1514
1515                         /* Baud rate has changed - update watermarks. */
1516                         tty_watermarks(tp);
1517                 }
1518
1519                 /* Copy new non-device driver parameters. */
1520                 tp->t_termios.c_iflag = t->c_iflag;
1521                 tp->t_termios.c_oflag = t->c_oflag;
1522                 tp->t_termios.c_lflag = t->c_lflag;
1523                 memcpy(&tp->t_termios.c_cc, t->c_cc, sizeof t->c_cc);
1524
1525                 ttydisc_optimize(tp);
1526
1527                 if ((t->c_lflag & ICANON) == 0) {
1528                         /*
1529                          * When in non-canonical mode, wake up all
1530                          * readers. Canonicalize any partial input. VMIN
1531                          * and VTIME could also be adjusted.
1532                          */
1533                         ttyinq_canonicalize(&tp->t_inq);
1534                         tty_wakeup(tp, FREAD);
1535                 }
1536
1537                 /*
1538                  * For packet mode: notify the PTY consumer that VSTOP
1539                  * and VSTART may have been changed.
1540                  */
1541                 if (tp->t_termios.c_iflag & IXON &&
1542                     tp->t_termios.c_cc[VSTOP] == CTRL('S') &&
1543                     tp->t_termios.c_cc[VSTART] == CTRL('Q'))
1544                         ttydevsw_pktnotify(tp, TIOCPKT_DOSTOP);
1545                 else
1546                         ttydevsw_pktnotify(tp, TIOCPKT_NOSTOP);
1547                 return (0);
1548         }
1549         case TIOCGETD:
1550                 /* For compatibility - we only support TTYDISC. */
1551                 *(int *)data = TTYDISC;
1552                 return (0);
1553         case TIOCGPGRP:
1554                 if (!tty_is_ctty(tp, td->td_proc))
1555                         return (ENOTTY);
1556
1557                 if (tp->t_pgrp != NULL)
1558                         *(int *)data = tp->t_pgrp->pg_id;
1559                 else
1560                         *(int *)data = NO_PID;
1561                 return (0);
1562         case TIOCGSID:
1563                 if (!tty_is_ctty(tp, td->td_proc))
1564                         return (ENOTTY);
1565
1566                 MPASS(tp->t_session);
1567                 *(int *)data = tp->t_session->s_sid;
1568                 return (0);
1569         case TIOCSCTTY: {
1570                 struct proc *p = td->td_proc;
1571
1572                 /* XXX: This looks awful. */
1573                 tty_unlock(tp);
1574                 sx_xlock(&proctree_lock);
1575                 tty_lock(tp);
1576
1577                 if (!SESS_LEADER(p)) {
1578                         /* Only the session leader may do this. */
1579                         sx_xunlock(&proctree_lock);
1580                         return (EPERM);
1581                 }
1582
1583                 if (tp->t_session != NULL && tp->t_session == p->p_session) {
1584                         /* This is already our controlling TTY. */
1585                         sx_xunlock(&proctree_lock);
1586                         return (0);
1587                 }
1588
1589                 if (p->p_session->s_ttyp != NULL ||
1590                     (tp->t_session != NULL && tp->t_session->s_ttyvp != NULL &&
1591                     tp->t_session->s_ttyvp->v_type != VBAD)) {
1592                         /*
1593                          * There is already a relation between a TTY and
1594                          * a session, or the caller is not the session
1595                          * leader.
1596                          *
1597                          * Allow the TTY to be stolen when the vnode is
1598                          * invalid, but the reference to the TTY is
1599                          * still active.  This allows immediate reuse of
1600                          * TTYs of which the session leader has been
1601                          * killed or the TTY revoked.
1602                          */
1603                         sx_xunlock(&proctree_lock);
1604                         return (EPERM);
1605                 }
1606
1607                 /* Connect the session to the TTY. */
1608                 tp->t_session = p->p_session;
1609                 tp->t_session->s_ttyp = tp;
1610                 tp->t_sessioncnt++;
1611                 sx_xunlock(&proctree_lock);
1612
1613                 /* Assign foreground process group. */
1614                 tp->t_pgrp = p->p_pgrp;
1615                 PROC_LOCK(p);
1616                 p->p_flag |= P_CONTROLT;
1617                 PROC_UNLOCK(p);
1618
1619                 return (0);
1620         }
1621         case TIOCSPGRP: {
1622                 struct pgrp *pg;
1623
1624                 /*
1625                  * XXX: Temporarily unlock the TTY to locate the process
1626                  * group. This code would be lot nicer if we would ever
1627                  * decompose proctree_lock.
1628                  */
1629                 tty_unlock(tp);
1630                 sx_slock(&proctree_lock);
1631                 pg = pgfind(*(int *)data);
1632                 if (pg != NULL)
1633                         PGRP_UNLOCK(pg);
1634                 if (pg == NULL || pg->pg_session != td->td_proc->p_session) {
1635                         sx_sunlock(&proctree_lock);
1636                         tty_lock(tp);
1637                         return (EPERM);
1638                 }
1639                 tty_lock(tp);
1640
1641                 /*
1642                  * Determine if this TTY is the controlling TTY after
1643                  * relocking the TTY.
1644                  */
1645                 if (!tty_is_ctty(tp, td->td_proc)) {
1646                         sx_sunlock(&proctree_lock);
1647                         return (ENOTTY);
1648                 }
1649                 tp->t_pgrp = pg;
1650                 sx_sunlock(&proctree_lock);
1651
1652                 /* Wake up the background process groups. */
1653                 cv_broadcast(&tp->t_bgwait);
1654                 return (0);
1655         }
1656         case TIOCFLUSH: {
1657                 int flags = *(int *)data;
1658
1659                 if (flags == 0)
1660                         flags = (FREAD|FWRITE);
1661                 else
1662                         flags &= (FREAD|FWRITE);
1663                 tty_flush(tp, flags);
1664                 return (0);
1665         }
1666         case TIOCDRAIN:
1667                 /* Drain TTY output. */
1668                 return tty_drain(tp);
1669         case TIOCCONS:
1670                 /* Set terminal as console TTY. */
1671                 if (*(int *)data) {
1672                         error = priv_check(td, PRIV_TTY_CONSOLE);
1673                         if (error)
1674                                 return (error);
1675
1676                         /*
1677                          * XXX: constty should really need to be locked!
1678                          * XXX: allow disconnected constty's to be stolen!
1679                          */
1680
1681                         if (constty == tp)
1682                                 return (0);
1683                         if (constty != NULL)
1684                                 return (EBUSY);
1685
1686                         tty_unlock(tp);
1687                         constty_set(tp);
1688                         tty_lock(tp);
1689                 } else if (constty == tp) {
1690                         constty_clear();
1691                 }
1692                 return (0);
1693         case TIOCGWINSZ:
1694                 /* Obtain window size. */
1695                 *(struct winsize*)data = tp->t_winsize;
1696                 return (0);
1697         case TIOCSWINSZ:
1698                 /* Set window size. */
1699                 if (bcmp(&tp->t_winsize, data, sizeof(struct winsize)) == 0)
1700                         return (0);
1701                 tp->t_winsize = *(struct winsize*)data;
1702                 tty_signal_pgrp(tp, SIGWINCH);
1703                 return (0);
1704         case TIOCEXCL:
1705                 tp->t_flags |= TF_EXCLUDE;
1706                 return (0);
1707         case TIOCNXCL:
1708                 tp->t_flags &= ~TF_EXCLUDE;
1709                 return (0);
1710         case TIOCSTOP:
1711                 tp->t_flags |= TF_STOPPED;
1712                 ttydevsw_pktnotify(tp, TIOCPKT_STOP);
1713                 return (0);
1714         case TIOCSTART:
1715                 tp->t_flags &= ~TF_STOPPED;
1716                 ttydevsw_outwakeup(tp);
1717                 ttydevsw_pktnotify(tp, TIOCPKT_START);
1718                 return (0);
1719         case TIOCSTAT:
1720                 tty_info(tp);
1721                 return (0);
1722         case TIOCSTI:
1723                 if ((fflag & FREAD) == 0 && priv_check(td, PRIV_TTY_STI))
1724                         return (EPERM);
1725                 if (!tty_is_ctty(tp, td->td_proc) &&
1726                     priv_check(td, PRIV_TTY_STI))
1727                         return (EACCES);
1728                 ttydisc_rint(tp, *(char *)data, 0);
1729                 ttydisc_rint_done(tp);
1730                 return (0);
1731         }
1732
1733 #ifdef COMPAT_43TTY
1734         return tty_ioctl_compat(tp, cmd, data, fflag, td);
1735 #else /* !COMPAT_43TTY */
1736         return (ENOIOCTL);
1737 #endif /* COMPAT_43TTY */
1738 }
1739
1740 int
1741 tty_ioctl(struct tty *tp, u_long cmd, void *data, int fflag, struct thread *td)
1742 {
1743         int error;
1744
1745         tty_lock_assert(tp, MA_OWNED);
1746
1747         if (tty_gone(tp))
1748                 return (ENXIO);
1749
1750         error = ttydevsw_ioctl(tp, cmd, data, td);
1751         if (error == ENOIOCTL)
1752                 error = tty_generic_ioctl(tp, cmd, data, fflag, td);
1753
1754         return (error);
1755 }
1756
1757 dev_t
1758 tty_udev(struct tty *tp)
1759 {
1760         if (tp->t_dev)
1761                 return dev2udev(tp->t_dev);
1762         else
1763                 return NODEV;
1764 }
1765
1766 int
1767 tty_checkoutq(struct tty *tp)
1768 {
1769
1770         /* 256 bytes should be enough to print a log message. */
1771         return (ttyoutq_bytesleft(&tp->t_outq) >= 256);
1772 }
1773
1774 void
1775 tty_hiwat_in_block(struct tty *tp)
1776 {
1777
1778         if ((tp->t_flags & TF_HIWAT_IN) == 0 &&
1779             tp->t_termios.c_iflag & IXOFF &&
1780             tp->t_termios.c_cc[VSTOP] != _POSIX_VDISABLE) {
1781                 /*
1782                  * Input flow control. Only enter the high watermark when we
1783                  * can successfully store the VSTOP character.
1784                  */
1785                 if (ttyoutq_write_nofrag(&tp->t_outq,
1786                     &tp->t_termios.c_cc[VSTOP], 1) == 0)
1787                         tp->t_flags |= TF_HIWAT_IN;
1788         } else {
1789                 /* No input flow control. */
1790                 tp->t_flags |= TF_HIWAT_IN;
1791         }
1792 }
1793
1794 void
1795 tty_hiwat_in_unblock(struct tty *tp)
1796 {
1797
1798         if (tp->t_flags & TF_HIWAT_IN &&
1799             tp->t_termios.c_iflag & IXOFF &&
1800             tp->t_termios.c_cc[VSTART] != _POSIX_VDISABLE) {
1801                 /*
1802                  * Input flow control. Only leave the high watermark when we
1803                  * can successfully store the VSTART character.
1804                  */
1805                 if (ttyoutq_write_nofrag(&tp->t_outq,
1806                     &tp->t_termios.c_cc[VSTART], 1) == 0)
1807                         tp->t_flags &= ~TF_HIWAT_IN;
1808         } else {
1809                 /* No input flow control. */
1810                 tp->t_flags &= ~TF_HIWAT_IN;
1811         }
1812
1813         if (!tty_gone(tp))
1814                 ttydevsw_inwakeup(tp);
1815 }
1816
1817 /*
1818  * TTY hooks interface.
1819  */
1820
1821 static int
1822 ttyhook_defrint(struct tty *tp, char c, int flags)
1823 {
1824
1825         if (ttyhook_rint_bypass(tp, &c, 1) != 1)
1826                 return (-1);
1827
1828         return (0);
1829 }
1830
1831 int
1832 ttyhook_register(struct tty **rtp, struct proc *p, int fd,
1833     struct ttyhook *th, void *softc)
1834 {
1835         struct tty *tp;
1836         struct file *fp;
1837 #ifdef CAPABILITIES
1838         struct file *fp_cap;
1839 #endif
1840         struct cdev *dev;
1841         struct cdevsw *cdp;
1842         struct filedesc *fdp;
1843         int error, ref;
1844
1845         /* Validate the file descriptor. */
1846         if ((fdp = p->p_fd) == NULL)
1847                 return (EBADF);
1848
1849         fp = fget_unlocked(fdp, fd);
1850         if (fp == NULL)
1851                 return (EBADF);
1852         if (fp->f_ops == &badfileops) {
1853                 error = EBADF;
1854                 goto done1;
1855         }
1856
1857 #ifdef CAPABILITIES
1858         fp_cap = fp;
1859         error = cap_funwrap(fp_cap, CAP_TTYHOOK, &fp);
1860         if (error)
1861                 return (error);
1862 #endif
1863
1864         /*
1865          * Make sure the vnode is bound to a character device.
1866          * Unlocked check for the vnode type is ok there, because we
1867          * only shall prevent calling devvn_refthread on the file that
1868          * never has been opened over a character device.
1869          */
1870         if (fp->f_type != DTYPE_VNODE || fp->f_vnode->v_type != VCHR) {
1871                 error = EINVAL;
1872                 goto done1;
1873         }
1874
1875         /* Make sure it is a TTY. */
1876         cdp = devvn_refthread(fp->f_vnode, &dev, &ref);
1877         if (cdp == NULL) {
1878                 error = ENXIO;
1879                 goto done1;
1880         }
1881         if (dev != fp->f_data) {
1882                 error = ENXIO;
1883                 goto done2;
1884         }
1885         if (cdp != &ttydev_cdevsw) {
1886                 error = ENOTTY;
1887                 goto done2;
1888         }
1889         tp = dev->si_drv1;
1890
1891         /* Try to attach the hook to the TTY. */
1892         error = EBUSY;
1893         tty_lock(tp);
1894         MPASS((tp->t_hook == NULL) == ((tp->t_flags & TF_HOOK) == 0));
1895         if (tp->t_flags & TF_HOOK)
1896                 goto done3;
1897
1898         tp->t_flags |= TF_HOOK;
1899         tp->t_hook = th;
1900         tp->t_hooksoftc = softc;
1901         *rtp = tp;
1902         error = 0;
1903
1904         /* Maybe we can switch into bypass mode now. */
1905         ttydisc_optimize(tp);
1906
1907         /* Silently convert rint() calls to rint_bypass() when possible. */
1908         if (!ttyhook_hashook(tp, rint) && ttyhook_hashook(tp, rint_bypass))
1909                 th->th_rint = ttyhook_defrint;
1910
1911 done3:  tty_unlock(tp);
1912 done2:  dev_relthread(dev, ref);
1913 done1:  fdrop(fp, curthread);
1914         return (error);
1915 }
1916
1917 void
1918 ttyhook_unregister(struct tty *tp)
1919 {
1920
1921         tty_lock_assert(tp, MA_OWNED);
1922         MPASS(tp->t_flags & TF_HOOK);
1923
1924         /* Disconnect the hook. */
1925         tp->t_flags &= ~TF_HOOK;
1926         tp->t_hook = NULL;
1927
1928         /* Maybe we need to leave bypass mode. */
1929         ttydisc_optimize(tp);
1930
1931         /* Maybe deallocate the TTY as well. */
1932         tty_rel_free(tp);
1933 }
1934
1935 /*
1936  * /dev/console handling.
1937  */
1938
1939 static int
1940 ttyconsdev_open(struct cdev *dev, int oflags, int devtype, struct thread *td)
1941 {
1942         struct tty *tp;
1943
1944         /* System has no console device. */
1945         if (dev_console_filename == NULL)
1946                 return (ENXIO);
1947
1948         /* Look up corresponding TTY by device name. */
1949         sx_slock(&tty_list_sx);
1950         TAILQ_FOREACH(tp, &tty_list, t_list) {
1951                 if (strcmp(dev_console_filename, tty_devname(tp)) == 0) {
1952                         dev_console->si_drv1 = tp;
1953                         break;
1954                 }
1955         }
1956         sx_sunlock(&tty_list_sx);
1957
1958         /* System console has no TTY associated. */
1959         if (dev_console->si_drv1 == NULL)
1960                 return (ENXIO);
1961
1962         return (ttydev_open(dev, oflags, devtype, td));
1963 }
1964
1965 static int
1966 ttyconsdev_write(struct cdev *dev, struct uio *uio, int ioflag)
1967 {
1968
1969         log_console(uio);
1970
1971         return (ttydev_write(dev, uio, ioflag));
1972 }
1973
1974 /*
1975  * /dev/console is a little different than normal TTY's.  When opened,
1976  * it determines which TTY to use.  When data gets written to it, it
1977  * will be logged in the kernel message buffer.
1978  */
1979 static struct cdevsw ttyconsdev_cdevsw = {
1980         .d_version      = D_VERSION,
1981         .d_open         = ttyconsdev_open,
1982         .d_close        = ttydev_close,
1983         .d_read         = ttydev_read,
1984         .d_write        = ttyconsdev_write,
1985         .d_ioctl        = ttydev_ioctl,
1986         .d_kqfilter     = ttydev_kqfilter,
1987         .d_poll         = ttydev_poll,
1988         .d_mmap         = ttydev_mmap,
1989         .d_name         = "ttyconsdev",
1990         .d_flags        = D_TTY,
1991 };
1992
1993 static void
1994 ttyconsdev_init(void *unused)
1995 {
1996
1997         dev_console = make_dev_credf(MAKEDEV_ETERNAL, &ttyconsdev_cdevsw, 0,
1998             NULL, UID_ROOT, GID_WHEEL, 0600, "console");
1999 }
2000
2001 SYSINIT(tty, SI_SUB_DRIVERS, SI_ORDER_FIRST, ttyconsdev_init, NULL);
2002
2003 void
2004 ttyconsdev_select(const char *name)
2005 {
2006
2007         dev_console_filename = name;
2008 }
2009
2010 /*
2011  * Debugging routines.
2012  */
2013
2014 #include "opt_ddb.h"
2015 #ifdef DDB
2016 #include <ddb/ddb.h>
2017 #include <ddb/db_sym.h>
2018
2019 static struct {
2020         int flag;
2021         char val;
2022 } ttystates[] = {
2023 #if 0
2024         { TF_NOPREFIX,          'N' },
2025 #endif
2026         { TF_INITLOCK,          'I' },
2027         { TF_CALLOUT,           'C' },
2028
2029         /* Keep these together -> 'Oi' and 'Oo'. */
2030         { TF_OPENED,            'O' },
2031         { TF_OPENED_IN,         'i' },
2032         { TF_OPENED_OUT,        'o' },
2033         { TF_OPENED_CONS,       'c' },
2034
2035         { TF_GONE,              'G' },
2036         { TF_OPENCLOSE,         'B' },
2037         { TF_ASYNC,             'Y' },
2038         { TF_LITERAL,           'L' },
2039
2040         /* Keep these together -> 'Hi' and 'Ho'. */
2041         { TF_HIWAT,             'H' },
2042         { TF_HIWAT_IN,          'i' },
2043         { TF_HIWAT_OUT,         'o' },
2044
2045         { TF_STOPPED,           'S' },
2046         { TF_EXCLUDE,           'X' },
2047         { TF_BYPASS,            'l' },
2048         { TF_ZOMBIE,            'Z' },
2049         { TF_HOOK,              's' },
2050
2051         /* Keep these together -> 'bi' and 'bo'. */
2052         { TF_BUSY,              'b' },
2053         { TF_BUSY_IN,           'i' },
2054         { TF_BUSY_OUT,          'o' },
2055
2056         { 0,                    '\0'},
2057 };
2058
2059 #define TTY_FLAG_BITS \
2060         "\20\1NOPREFIX\2INITLOCK\3CALLOUT\4OPENED_IN\5OPENED_OUT\6GONE" \
2061         "\7OPENCLOSE\10ASYNC\11LITERAL\12HIWAT_IN\13HIWAT_OUT\14STOPPED" \
2062         "\15EXCLUDE\16BYPASS\17ZOMBIE\20HOOK"
2063
2064 #define DB_PRINTSYM(name, addr) \
2065         db_printf("%s  " #name ": ", sep); \
2066         db_printsym((db_addr_t) addr, DB_STGY_ANY); \
2067         db_printf("\n");
2068
2069 static void
2070 _db_show_devsw(const char *sep, const struct ttydevsw *tsw)
2071 {
2072         db_printf("%sdevsw: ", sep);
2073         db_printsym((db_addr_t)tsw, DB_STGY_ANY);
2074         db_printf(" (%p)\n", tsw);
2075         DB_PRINTSYM(open, tsw->tsw_open);
2076         DB_PRINTSYM(close, tsw->tsw_close);
2077         DB_PRINTSYM(outwakeup, tsw->tsw_outwakeup);
2078         DB_PRINTSYM(inwakeup, tsw->tsw_inwakeup);
2079         DB_PRINTSYM(ioctl, tsw->tsw_ioctl);
2080         DB_PRINTSYM(param, tsw->tsw_param);
2081         DB_PRINTSYM(modem, tsw->tsw_modem);
2082         DB_PRINTSYM(mmap, tsw->tsw_mmap);
2083         DB_PRINTSYM(pktnotify, tsw->tsw_pktnotify);
2084         DB_PRINTSYM(free, tsw->tsw_free);
2085 }
2086 static void
2087 _db_show_hooks(const char *sep, const struct ttyhook *th)
2088 {
2089         db_printf("%shook: ", sep);
2090         db_printsym((db_addr_t)th, DB_STGY_ANY);
2091         db_printf(" (%p)\n", th);
2092         if (th == NULL)
2093                 return;
2094         DB_PRINTSYM(rint, th->th_rint);
2095         DB_PRINTSYM(rint_bypass, th->th_rint_bypass);
2096         DB_PRINTSYM(rint_done, th->th_rint_done);
2097         DB_PRINTSYM(rint_poll, th->th_rint_poll);
2098         DB_PRINTSYM(getc_inject, th->th_getc_inject);
2099         DB_PRINTSYM(getc_capture, th->th_getc_capture);
2100         DB_PRINTSYM(getc_poll, th->th_getc_poll);
2101         DB_PRINTSYM(close, th->th_close);
2102 }
2103
2104 static void
2105 _db_show_termios(const char *name, const struct termios *t)
2106 {
2107
2108         db_printf("%s: iflag 0x%x oflag 0x%x cflag 0x%x "
2109             "lflag 0x%x ispeed %u ospeed %u\n", name,
2110             t->c_iflag, t->c_oflag, t->c_cflag, t->c_lflag,
2111             t->c_ispeed, t->c_ospeed);
2112 }
2113
2114 /* DDB command to show TTY statistics. */
2115 DB_SHOW_COMMAND(tty, db_show_tty)
2116 {
2117         struct tty *tp;
2118
2119         if (!have_addr) {
2120                 db_printf("usage: show tty <addr>\n");
2121                 return;
2122         }
2123         tp = (struct tty *)addr;
2124
2125         db_printf("0x%p: %s\n", tp, tty_devname(tp));
2126         db_printf("\tmtx: %p\n", tp->t_mtx);
2127         db_printf("\tflags: %b\n", tp->t_flags, TTY_FLAG_BITS);
2128         db_printf("\trevokecnt: %u\n", tp->t_revokecnt);
2129
2130         /* Buffering mechanisms. */
2131         db_printf("\tinq: %p begin %u linestart %u reprint %u end %u "
2132             "nblocks %u quota %u\n", &tp->t_inq, tp->t_inq.ti_begin,
2133             tp->t_inq.ti_linestart, tp->t_inq.ti_reprint, tp->t_inq.ti_end,
2134             tp->t_inq.ti_nblocks, tp->t_inq.ti_quota);
2135         db_printf("\toutq: %p begin %u end %u nblocks %u quota %u\n",
2136             &tp->t_outq, tp->t_outq.to_begin, tp->t_outq.to_end,
2137             tp->t_outq.to_nblocks, tp->t_outq.to_quota);
2138         db_printf("\tinlow: %zu\n", tp->t_inlow);
2139         db_printf("\toutlow: %zu\n", tp->t_outlow);
2140         _db_show_termios("\ttermios", &tp->t_termios);
2141         db_printf("\twinsize: row %u col %u xpixel %u ypixel %u\n",
2142             tp->t_winsize.ws_row, tp->t_winsize.ws_col,
2143             tp->t_winsize.ws_xpixel, tp->t_winsize.ws_ypixel);
2144         db_printf("\tcolumn: %u\n", tp->t_column);
2145         db_printf("\twritepos: %u\n", tp->t_writepos);
2146         db_printf("\tcompatflags: 0x%x\n", tp->t_compatflags);
2147
2148         /* Init/lock-state devices. */
2149         _db_show_termios("\ttermios_init_in", &tp->t_termios_init_in);
2150         _db_show_termios("\ttermios_init_out", &tp->t_termios_init_out);
2151         _db_show_termios("\ttermios_lock_in", &tp->t_termios_lock_in);
2152         _db_show_termios("\ttermios_lock_out", &tp->t_termios_lock_out);
2153
2154         /* Hooks */
2155         _db_show_devsw("\t", tp->t_devsw);
2156         _db_show_hooks("\t", tp->t_hook);
2157
2158         /* Process info. */
2159         db_printf("\tpgrp: %p gid %d jobc %d\n", tp->t_pgrp,
2160             tp->t_pgrp ? tp->t_pgrp->pg_id : 0,
2161             tp->t_pgrp ? tp->t_pgrp->pg_jobc : 0);
2162         db_printf("\tsession: %p", tp->t_session);
2163         if (tp->t_session != NULL)
2164             db_printf(" count %u leader %p tty %p sid %d login %s",
2165                 tp->t_session->s_count, tp->t_session->s_leader,
2166                 tp->t_session->s_ttyp, tp->t_session->s_sid,
2167                 tp->t_session->s_login);
2168         db_printf("\n");
2169         db_printf("\tsessioncnt: %u\n", tp->t_sessioncnt);
2170         db_printf("\tdevswsoftc: %p\n", tp->t_devswsoftc);
2171         db_printf("\thooksoftc: %p\n", tp->t_hooksoftc);
2172         db_printf("\tdev: %p\n", tp->t_dev);
2173 }
2174
2175 /* DDB command to list TTYs. */
2176 DB_SHOW_ALL_COMMAND(ttys, db_show_all_ttys)
2177 {
2178         struct tty *tp;
2179         size_t isiz, osiz;
2180         int i, j;
2181
2182         /* Make the output look like `pstat -t'. */
2183         db_printf("PTR        ");
2184 #if defined(__LP64__)
2185         db_printf("        ");
2186 #endif
2187         db_printf("      LINE   INQ  CAN  LIN  LOW  OUTQ  USE  LOW   "
2188             "COL  SESS  PGID STATE\n");
2189
2190         TAILQ_FOREACH(tp, &tty_list, t_list) {
2191                 isiz = tp->t_inq.ti_nblocks * TTYINQ_DATASIZE;
2192                 osiz = tp->t_outq.to_nblocks * TTYOUTQ_DATASIZE;
2193
2194                 db_printf("%p %10s %5zu %4u %4u %4zu %5zu %4u %4zu %5u %5d %5d ",
2195                     tp,
2196                     tty_devname(tp),
2197                     isiz,
2198                     tp->t_inq.ti_linestart - tp->t_inq.ti_begin,
2199                     tp->t_inq.ti_end - tp->t_inq.ti_linestart,
2200                     isiz - tp->t_inlow,
2201                     osiz,
2202                     tp->t_outq.to_end - tp->t_outq.to_begin,
2203                     osiz - tp->t_outlow,
2204                     MIN(tp->t_column, 99999),
2205                     tp->t_session ? tp->t_session->s_sid : 0,
2206                     tp->t_pgrp ? tp->t_pgrp->pg_id : 0);
2207
2208                 /* Flag bits. */
2209                 for (i = j = 0; ttystates[i].flag; i++)
2210                         if (tp->t_flags & ttystates[i].flag) {
2211                                 db_printf("%c", ttystates[i].val);
2212                                 j++;
2213                         }
2214                 if (j == 0)
2215                         db_printf("-");
2216                 db_printf("\n");
2217         }
2218 }
2219 #endif /* DDB */