nmdm.c revision 119418
15992SN/A/* 25992SN/A * Copyright (c) 1982, 1986, 1989, 1993 35992SN/A * The Regents of the University of California. All rights reserved. 45992SN/A * 55992SN/A * Redistribution and use in source and binary forms, with or without 65992SN/A * modification, are permitted provided that the following conditions 75992SN/A * are met: 85992SN/A * 1. Redistributions of source code must retain the above copyright 95992SN/A * notice, this list of conditions and the following disclaimer. 105992SN/A * 2. Redistributions in binary form must reproduce the above copyright 115992SN/A * notice, this list of conditions and the following disclaimer in the 125992SN/A * documentation and/or other materials provided with the distribution. 135992SN/A * 3. All advertising materials mentioning features or use of this software 145992SN/A * must display the following acknowledgement: 155992SN/A * This product includes software developed by the University of 165992SN/A * California, Berkeley and its contributors. 175992SN/A * 4. Neither the name of the University nor the names of its contributors 185992SN/A * may be used to endorse or promote products derived from this software 195992SN/A * without specific prior written permission. 205992SN/A * 215992SN/A * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 225992SN/A * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 235992SN/A * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 245992SN/A * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 255992SN/A * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 265992SN/A * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 275992SN/A * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 285992SN/A * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 295992SN/A * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 305992SN/A * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 315992SN/A * SUCH DAMAGE. 325992SN/A * 335992SN/A */ 345992SN/A 355992SN/A#include <sys/cdefs.h> 365992SN/A__FBSDID("$FreeBSD: head/sys/dev/nmdm/nmdm.c 119418 2003-08-24 17:55:58Z obrien $"); 375992SN/A 385992SN/A/* 395992SN/A * Pseudo-nulmodem driver 405992SN/A * Mighty handy for use with serial console in Vmware 415992SN/A */ 425992SN/A 435992SN/A#include "opt_compat.h" 445992SN/A#include "opt_tty.h" 455992SN/A 465992SN/A#include <sys/param.h> 475992SN/A#include <sys/systm.h> 485992SN/A#if defined(COMPAT_43) || defined(COMPAT_SUNOS) 495992SN/A#include <sys/ioctl_compat.h> 505992SN/A#endif 515992SN/A#include <sys/proc.h> 525992SN/A#include <sys/tty.h> 535992SN/A#include <sys/conf.h> 545992SN/A#include <sys/fcntl.h> 555992SN/A#include <sys/poll.h> 565992SN/A#include <sys/kernel.h> 575992SN/A#include <sys/vnode.h> 585992SN/A#include <sys/signalvar.h> 595992SN/A#include <sys/malloc.h> 605992SN/A 615992SN/AMALLOC_DEFINE(M_NLMDM, "nullmodem", "nullmodem data structures"); 625992SN/A 635992SN/Astatic void nmdmstart(struct tty *tp); 645992SN/Astatic void nmdmstop(struct tty *tp, int rw); 655992SN/Astatic void wakeup_other(struct tty *tp, int flag); 665992SN/Astatic void nmdminit(int); 675992SN/Astatic int nmdmshutdown(void); 685992SN/A 695992SN/Astatic d_open_t nmdmopen; 705992SN/Astatic d_close_t nmdmclose; 715992SN/Astatic d_read_t nmdmread; 725992SN/Astatic d_write_t nmdmwrite; 735992SN/Astatic d_ioctl_t nmdmioctl; 745992SN/A 757084SN/A#define CDEV_MAJOR 18 767084SN/Astatic struct cdevsw nmdm_cdevsw = { 777084SN/A .d_open = nmdmopen, 787084SN/A .d_close = nmdmclose, 795992SN/A .d_read = nmdmread, 805992SN/A .d_write = nmdmwrite, 815992SN/A .d_ioctl = nmdmioctl, 825992SN/A .d_poll = ttypoll, 835992SN/A .d_name = "pts", 845992SN/A .d_maj = CDEV_MAJOR, 855992SN/A .d_flags = D_TTY, 865992SN/A}; 87 88#define BUFSIZ 100 /* Chunk size iomoved to/from user */ 89#define NMDM_MAX_NUM 128 /* Artificially limit # devices. */ 90#define PF_STOPPED 0x10 /* user told stopped */ 91 92struct softpart { 93 struct tty nm_tty; 94 dev_t dev; 95 int modemsignals; /* bits defined in sys/ttycom.h */ 96 int gotbreak; 97}; 98 99struct nm_softc { 100 int pt_flags; 101 struct softpart part1, part2; 102 struct prison *pt_prison; 103}; 104 105static void 106nmdm_crossover(struct nm_softc *pti, 107 struct softpart *ourpart, 108 struct softpart *otherpart); 109 110#define GETPARTS(tp, ourpart, otherpart) \ 111do { \ 112 struct nm_softc *pti = tp->t_dev->si_drv1; \ 113 if (tp == &pti->part1.nm_tty) { \ 114 ourpart = &pti->part1; \ 115 otherpart = &pti->part2; \ 116 } else { \ 117 ourpart = &pti->part2; \ 118 otherpart = &pti->part1; \ 119 } \ 120} while (0) 121 122/* 123 * This function creates and initializes a pair of ttys. 124 */ 125static void 126nmdminit(n) 127 int n; 128{ 129 dev_t dev1, dev2; 130 struct nm_softc *pt; 131 132 /* For now we only map the lower 8 bits of the minor */ 133 if (n & ~0xff) 134 return; 135 136 pt = malloc(sizeof(*pt), M_NLMDM, M_WAITOK); 137 bzero(pt, sizeof(*pt)); 138 pt->part1.dev = dev1 = make_dev(&nmdm_cdevsw, n+n, 139 0, 0, 0666, "nmdm%dA", n); 140 pt->part2.dev = dev2 = make_dev(&nmdm_cdevsw, n+n+1, 141 0, 0, 0666, "nmdm%dB", n); 142 143 dev1->si_drv1 = dev2->si_drv1 = pt; 144 dev1->si_tty = &pt->part1.nm_tty; 145 dev2->si_tty = &pt->part2.nm_tty; 146 ttyregister(&pt->part1.nm_tty); 147 ttyregister(&pt->part2.nm_tty); 148 pt->part1.nm_tty.t_oproc = nmdmstart; 149 pt->part2.nm_tty.t_oproc = nmdmstart; 150 pt->part1.nm_tty.t_stop = nmdmstop; 151 pt->part2.nm_tty.t_dev = dev1; 152 pt->part1.nm_tty.t_dev = dev2; 153 pt->part2.nm_tty.t_stop = nmdmstop; 154} 155 156/* 157 * Device opened from userland 158 */ 159static int 160nmdmopen(dev_t dev, int flag, int devtype, struct thread *td) 161{ 162 register struct tty *tp, *tp2; 163 int error; 164 int minr; 165 dev_t nextdev; 166 struct nm_softc *pti; 167 int is_b; 168 int pair; 169 struct softpart *ourpart, *otherpart; 170 171 /* 172 * XXX: Gross hack for DEVFS: 173 * If we openned this device, ensure we have the 174 * next one too, so people can open it. 175 */ 176 minr = dev2unit(dev); 177 pair = minr >> 1; 178 is_b = minr & 1; 179 180 if (pair < (NMDM_MAX_NUM - 1)) { 181 nextdev = makedev(major(dev), minr + 2); 182 if (!nextdev->si_drv1) { 183 nmdminit(pair + 1); 184 } 185 } else { /* Limit ourselves to 128 of them for now */ 186 if (pair > (NMDM_MAX_NUM - 1)) 187 return (ENXIO); 188 } 189 if (!dev->si_drv1) 190 nmdminit(pair); 191 192 if (!dev->si_drv1) 193 return(ENXIO); 194 195 pti = dev->si_drv1; 196 if (is_b) 197 tp = &pti->part2.nm_tty; 198 else 199 tp = &pti->part1.nm_tty; 200 GETPARTS(tp, ourpart, otherpart); 201 202 tp2 = &otherpart->nm_tty; 203 ourpart->modemsignals |= TIOCM_LE; 204 205 if ((tp->t_state & TS_ISOPEN) == 0) { 206 ttychars(tp); /* Set up default chars */ 207 tp->t_iflag = TTYDEF_IFLAG; 208 tp->t_oflag = TTYDEF_OFLAG; 209 tp->t_lflag = TTYDEF_LFLAG; 210 tp->t_cflag = TTYDEF_CFLAG; 211 tp->t_ispeed = tp->t_ospeed = TTYDEF_SPEED; 212 } else if (tp->t_state & TS_XCLUDE && suser(td)) { 213 return (EBUSY); 214 } else if (pti->pt_prison != td->td_ucred->cr_prison) { 215 return (EBUSY); 216 } 217 218 /* 219 * If the other side is open we have carrier 220 */ 221 if (tp2->t_state & TS_ISOPEN) { 222 (void)(*linesw[tp->t_line].l_modem)(tp, 1); 223 } 224 225 /* 226 * And the other side gets carrier as we are now open. 227 */ 228 (void)(*linesw[tp2->t_line].l_modem)(tp2, 1); 229 230 /* External processing makes no sense here */ 231 tp->t_lflag &= ~EXTPROC; 232 233 /* 234 * Wait here if we don't have carrier. 235 */ 236#if 0 237 while ((tp->t_state & TS_CARR_ON) == 0) { 238 if (flag & FNONBLOCK) 239 break; 240 error = ttysleep(tp, TSA_CARR_ON(tp), TTIPRI | PCATCH, 241 "nmdopn", 0); 242 if (error) 243 return (error); 244 } 245#endif 246 247 /* 248 * Give the line disciplin a chance to set this end up. 249 */ 250 error = (*linesw[tp->t_line].l_open)(dev, tp); 251 252 /* 253 * Wake up the other side. 254 * Theoretically not needed. 255 */ 256 ourpart->modemsignals |= TIOCM_DTR; 257 nmdm_crossover(pti, ourpart, otherpart); 258 if (error == 0) 259 wakeup_other(tp, FREAD|FWRITE); /* XXX */ 260 return (error); 261} 262 263/* 264 * Device closed again 265 */ 266static int 267nmdmclose(dev_t dev, int flag, int mode, struct thread *td) 268{ 269 register struct tty *tp, *tp2; 270 int err; 271 struct softpart *ourpart, *otherpart; 272 273 /* 274 * let the other end know that the game is up 275 */ 276 tp = dev->si_tty; 277 GETPARTS(tp, ourpart, otherpart); 278 tp2 = &otherpart->nm_tty; 279 (void)(*linesw[tp2->t_line].l_modem)(tp2, 0); 280 281 /* 282 * XXX MDMBUF makes no sense for nmdms but would inhibit the above 283 * l_modem(). CLOCAL makes sense but isn't supported. Special 284 * l_modem()s that ignore carrier drop make no sense for nmdms but 285 * may be in use because other parts of the line discipline make 286 * sense for nmdms. Recover by doing everything that a normal 287 * ttymodem() would have done except for sending a SIGHUP. 288 */ 289 if (tp2->t_state & TS_ISOPEN) { 290 tp2->t_state &= ~(TS_CARR_ON | TS_CONNECTED); 291 tp2->t_state |= TS_ZOMBIE; 292 ttyflush(tp2, FREAD | FWRITE); 293 } 294 295 err = (*linesw[tp->t_line].l_close)(tp, flag); 296 ourpart->modemsignals &= ~TIOCM_DTR; 297 nmdm_crossover(dev->si_drv1, ourpart, otherpart); 298 nmdmstop(tp, FREAD|FWRITE); 299 (void) ttyclose(tp); 300 return (err); 301} 302 303/* 304 * handle read(2) request from userland 305 */ 306static int 307nmdmread(dev_t dev, struct uio *uio, int flag) 308{ 309 int error = 0; 310 struct tty *tp, *tp2; 311 struct softpart *ourpart, *otherpart; 312 313 tp = dev->si_tty; 314 GETPARTS(tp, ourpart, otherpart); 315 tp2 = &otherpart->nm_tty; 316 317#if 0 318 if (tp2->t_state & TS_ISOPEN) { 319 error = (*linesw[tp->t_line].l_read)(tp, uio, flag); 320 wakeup_other(tp, FWRITE); 321 } else { 322 if (flag & IO_NDELAY) { 323 return (EWOULDBLOCK); 324 } 325 error = tsleep(TSA_PTC_READ(tp), 326 TTIPRI | PCATCH, "nmdout", 0); 327 } 328 } 329#else 330 if ((error = (*linesw[tp->t_line].l_read)(tp, uio, flag)) == 0) 331 wakeup_other(tp, FWRITE); 332#endif 333 return (error); 334} 335 336/* 337 * Write to pseudo-tty. 338 * Wakeups of controlling tty will happen 339 * indirectly, when tty driver calls nmdmstart. 340 */ 341static int 342nmdmwrite(dev_t dev, struct uio *uio, int flag) 343{ 344 register u_char *cp = 0; 345 register int cc = 0; 346 u_char locbuf[BUFSIZ]; 347 int cnt = 0; 348 int error = 0; 349 struct tty *tp1, *tp; 350 struct softpart *ourpart, *otherpart; 351 352 tp1 = dev->si_tty; 353 /* 354 * Get the other tty struct. 355 * basically we are writing into the INPUT side of the other device. 356 */ 357 GETPARTS(tp1, ourpart, otherpart); 358 tp = &otherpart->nm_tty; 359 360again: 361 if ((tp->t_state & TS_ISOPEN) == 0) 362 return (EIO); 363 while (uio->uio_resid > 0 || cc > 0) { 364 /* 365 * Fill up the buffer if it's empty 366 */ 367 if (cc == 0) { 368 cc = min(uio->uio_resid, BUFSIZ); 369 cp = locbuf; 370 error = uiomove((caddr_t)cp, cc, uio); 371 if (error) 372 return (error); 373 /* check again for safety */ 374 if ((tp->t_state & TS_ISOPEN) == 0) { 375 /* adjust for data copied in but not written */ 376 uio->uio_resid += cc; 377 return (EIO); 378 } 379 } 380 while (cc > 0) { 381 if (((tp->t_rawq.c_cc + tp->t_canq.c_cc) >= (TTYHOG-2)) 382 && ((tp->t_canq.c_cc > 0) || !(tp->t_iflag&ICANON))) { 383 /* 384 * Come here to wait for space in outq, 385 * or space in rawq, or an empty canq. 386 */ 387 wakeup(TSA_HUP_OR_INPUT(tp)); 388 if ((tp->t_state & TS_CONNECTED) == 0) { 389 /* 390 * Data piled up because not connected. 391 * Adjust for data copied in but 392 * not written. 393 */ 394 uio->uio_resid += cc; 395 return (EIO); 396 } 397 if (flag & IO_NDELAY) { 398 /* 399 * Don't wait if asked not to. 400 * Adjust for data copied in but 401 * not written. 402 */ 403 uio->uio_resid += cc; 404 if (cnt == 0) 405 return (EWOULDBLOCK); 406 return (0); 407 } 408 error = tsleep(TSA_PTC_WRITE(tp), 409 TTOPRI | PCATCH, "nmdout", 0); 410 if (error) { 411 /* 412 * Tsleep returned (signal?). 413 * Go find out what the user wants. 414 * adjust for data copied in but 415 * not written 416 */ 417 uio->uio_resid += cc; 418 return (error); 419 } 420 goto again; 421 } 422 (*linesw[tp->t_line].l_rint)(*cp++, tp); 423 cnt++; 424 cc--; 425 } 426 cc = 0; 427 } 428 return (0); 429} 430 431/* 432 * Start output on pseudo-tty. 433 * Wake up process selecting or sleeping for input from controlling tty. 434 */ 435static void 436nmdmstart(struct tty *tp) 437{ 438 register struct nm_softc *pti = tp->t_dev->si_drv1; 439 440 if (tp->t_state & TS_TTSTOP) 441 return; 442 pti->pt_flags &= ~PF_STOPPED; 443 wakeup_other(tp, FREAD); 444} 445 446/* Wakes up the OTHER tty;*/ 447static void 448wakeup_other(struct tty *tp, int flag) 449{ 450 struct softpart *ourpart, *otherpart; 451 452 GETPARTS(tp, ourpart, otherpart); 453 if (flag & FREAD) { 454 selwakeup(&otherpart->nm_tty.t_rsel); 455 wakeup(TSA_PTC_READ((&otherpart->nm_tty))); 456 } 457 if (flag & FWRITE) { 458 selwakeup(&otherpart->nm_tty.t_wsel); 459 wakeup(TSA_PTC_WRITE((&otherpart->nm_tty))); 460 } 461} 462 463/* 464 * stopped output on tty, called when device is closed 465 */ 466static void 467nmdmstop(register struct tty *tp, int flush) 468{ 469 struct nm_softc *pti = tp->t_dev->si_drv1; 470 int flag; 471 472 /* note: FLUSHREAD and FLUSHWRITE already ok */ 473 if (flush == 0) { 474 flush = TIOCPKT_STOP; 475 pti->pt_flags |= PF_STOPPED; 476 } else 477 pti->pt_flags &= ~PF_STOPPED; 478 /* change of perspective */ 479 flag = 0; 480 if (flush & FREAD) 481 flag |= FWRITE; 482 if (flush & FWRITE) 483 flag |= FREAD; 484 wakeup_other(tp, flag); 485} 486 487/* 488 * handle ioctl(2) request from userland 489 */ 490static int 491nmdmioctl(dev_t dev, u_long cmd, caddr_t data, int flag, struct thread *td) 492{ 493 register struct tty *tp = dev->si_tty; 494 struct nm_softc *pti = dev->si_drv1; 495 int error, s; 496 register struct tty *tp2; 497 struct softpart *ourpart, *otherpart; 498 499 s = spltty(); 500 GETPARTS(tp, ourpart, otherpart); 501 tp2 = &otherpart->nm_tty; 502 503 error = (*linesw[tp->t_line].l_ioctl)(tp, cmd, data, flag, td); 504 if (error == ENOIOCTL) 505 error = ttioctl(tp, cmd, data, flag); 506 if (error == ENOIOCTL) { 507 switch (cmd) { 508 case TIOCSBRK: 509 otherpart->gotbreak = 1; 510 break; 511 case TIOCCBRK: 512 break; 513 case TIOCSDTR: 514 ourpart->modemsignals |= TIOCM_DTR; 515 break; 516 case TIOCCDTR: 517 ourpart->modemsignals &= TIOCM_DTR; 518 break; 519 case TIOCMSET: 520 ourpart->modemsignals = *(int *)data; 521 otherpart->modemsignals = *(int *)data; 522 break; 523 case TIOCMBIS: 524 ourpart->modemsignals |= *(int *)data; 525 break; 526 case TIOCMBIC: 527 ourpart->modemsignals &= ~(*(int *)data); 528 otherpart->modemsignals &= ~(*(int *)data); 529 break; 530 case TIOCMGET: 531 *(int *)data = ourpart->modemsignals; 532 break; 533 case TIOCMSDTRWAIT: 534 break; 535 case TIOCMGDTRWAIT: 536 *(int *)data = 0; 537 break; 538 case TIOCTIMESTAMP: 539 /* FALLTHROUGH */ 540 case TIOCDCDTIMESTAMP: 541 default: 542 splx(s); 543 error = ENOTTY; 544 return (error); 545 } 546 error = 0; 547 nmdm_crossover(pti, ourpart, otherpart); 548 } 549 splx(s); 550 return (error); 551} 552 553static void 554nmdm_crossover(struct nm_softc *pti, struct softpart *ourpart, 555 struct softpart *otherpart) 556{ 557 otherpart->modemsignals &= ~(TIOCM_CTS|TIOCM_CAR); 558 if (ourpart->modemsignals & TIOCM_RTS) 559 otherpart->modemsignals |= TIOCM_CTS; 560 if (ourpart->modemsignals & TIOCM_DTR) 561 otherpart->modemsignals |= TIOCM_CAR; 562} 563 564/* 565 * Module handling 566 */ 567static int 568nmdm_modevent(module_t mod, int type, void *data) 569{ 570 int error = 0; 571 572 switch(type) { 573 case MOD_LOAD: /* start with 4 of them */ 574 nmdminit(0); 575 nmdminit(1); 576 nmdminit(2); 577 nmdminit(3); 578 break; 579 580 case MOD_SHUTDOWN: 581 /* FALLTHROUGH */ 582 case MOD_UNLOAD: 583 nmdmshutdown(); 584 break; 585 default: 586 error = EOPNOTSUPP; 587 } 588 return (error); 589} 590 591/* 592 * Handle teardown of device 593 */ 594static int 595nmdmshutdown(void) 596{ 597 int i; 598 dev_t nextdev1; 599 dev_t nextdev2; 600 void * ptr1; 601 602 for(i = 0;( i < NMDM_MAX_NUM) ;i++) { 603 nextdev1 = makedev(CDEV_MAJOR, (i+i) ); 604 nextdev2 = makedev(CDEV_MAJOR, (i+i) + 1); 605 ptr1 = nextdev1->si_drv1; 606 if (ptr1) { 607 revoke_and_destroy_dev(nextdev1); 608 revoke_and_destroy_dev(nextdev2); 609 free(ptr1, M_NLMDM); 610 } else { 611 freedev(nextdev1); 612 freedev(nextdev2); 613 } 614 } 615 return(0); 616} 617 618DEV_MODULE(nmdm, nmdm_modevent, NULL); 619