1 /*- 2 * Copyright (c) 1999-2002 Poul-Henning Kamp 3 * All rights reserved. 4 * 5 * Redistribution and use in source and binary forms, with or without 6 * modification, are permitted provided that the following conditions 7 * are met: 8 * 1. Redistributions of source code must retain the above copyright 9 * notice, this list of conditions and the following disclaimer. 10 * 2. Redistributions in binary form must reproduce the above copyright 11 * notice, this list of conditions and the following disclaimer in the 12 * documentation and/or other materials provided with the distribution. 13 * 14 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 15 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 16 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 17 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 18 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 19 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 20 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 21 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 22 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 23 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 24 * SUCH DAMAGE. 25 */ 26 27 #include <sys/cdefs.h> 28 __FBSDID("$FreeBSD$"); 29 30 #include <sys/param.h> 31 #include <sys/kernel.h> 32 #include <sys/systm.h> 33 #include <sys/bio.h> 34 #include <sys/lock.h> 35 #include <sys/mutex.h> 36 #include <sys/sysctl.h> 37 #include <sys/module.h> 38 #include <sys/malloc.h> 39 #include <sys/conf.h> 40 #include <sys/vnode.h> 41 #include <sys/queue.h> 42 #include <sys/poll.h> 43 #include <sys/ctype.h> 44 #include <sys/tty.h> 45 #include <machine/stdarg.h> 46 47 static MALLOC_DEFINE(M_DEVT, "cdev", "cdev storage"); 48 49 /* Built at compile time from sys/conf/majors */ 50 extern unsigned char reserved_majors[256]; 51 52 /* 53 * This is the number of hash-buckets. Experiments with 'real-life' 54 * dev_t's show that a prime halfway between two powers of two works 55 * best. 56 */ 57 #define DEVT_HASH 83 58 59 /* The number of struct cdev *'s we can create before malloc(9) kick in. */ 60 #define DEVT_STASH 50 61 62 static struct cdev devt_stash[DEVT_STASH]; 63 64 static LIST_HEAD(, cdev) dev_hash[DEVT_HASH]; 65 66 static LIST_HEAD(, cdev) dev_free; 67 68 static int free_devt; 69 SYSCTL_INT(_debug, OID_AUTO, free_devt, CTLFLAG_RW, &free_devt, 0, ""); 70 71 static struct mtx devmtx; 72 static void freedev(struct cdev *dev); 73 static struct cdev *newdev(int x, int y); 74 75 76 static void 77 devlock(void) 78 { 79 if (!mtx_initialized(&devmtx)) 80 mtx_init(&devmtx, "cdev", NULL, MTX_DEF); 81 mtx_lock(&devmtx); 82 } 83 84 static void 85 devunlock(void) 86 { 87 mtx_unlock(&devmtx); 88 } 89 90 void 91 dev_ref(struct cdev *dev) 92 { 93 devlock(); 94 dev->si_refcount++; 95 devunlock(); 96 } 97 98 void 99 dev_rel(struct cdev *dev) 100 { 101 devlock(); 102 dev->si_refcount--; 103 KASSERT(dev->si_refcount >= 0, 104 ("dev_rel(%s) gave negative count", devtoname(dev))); 105 if (dev->si_devsw == NULL && dev->si_refcount == 0) { 106 LIST_REMOVE(dev, si_list); 107 freedev(dev); 108 } 109 devunlock(); 110 } 111 112 void 113 cdevsw_ref(struct cdevsw *csw) 114 { 115 devlock(); 116 csw->d_refcount++; 117 devunlock(); 118 } 119 120 void 121 cdevsw_rel(struct cdevsw *csw) 122 { 123 devlock(); 124 csw->d_refcount--; 125 KASSERT(csw->d_refcount >= 0, 126 ("cdevsw_vrel(%s) gave negative count", csw->d_name)); 127 devunlock(); 128 } 129 130 int 131 nullop(void) 132 { 133 134 return (0); 135 } 136 137 int 138 eopnotsupp(void) 139 { 140 141 return (EOPNOTSUPP); 142 } 143 144 static int 145 enxio(void) 146 { 147 return (ENXIO); 148 } 149 150 static int 151 enodev(void) 152 { 153 return (ENODEV); 154 } 155 156 /* Define a dead_cdevsw for use when devices leave unexpectedly. */ 157 158 #define dead_open (d_open_t *)enxio 159 #define dead_close (d_close_t *)enxio 160 #define dead_read (d_read_t *)enxio 161 #define dead_write (d_write_t *)enxio 162 #define dead_ioctl (d_ioctl_t *)enxio 163 #define dead_poll (d_poll_t *)enodev 164 #define dead_mmap (d_mmap_t *)enodev 165 166 static void 167 dead_strategy(struct bio *bp) 168 { 169 170 biofinish(bp, NULL, ENXIO); 171 } 172 173 #define dead_dump (dumper_t *)enxio 174 #define dead_kqfilter (d_kqfilter_t *)enxio 175 176 static struct cdevsw dead_cdevsw = { 177 .d_version = D_VERSION, 178 .d_flags = D_NEEDGIANT, /* XXX: does dead_strategy need this ? */ 179 .d_open = dead_open, 180 .d_close = dead_close, 181 .d_read = dead_read, 182 .d_write = dead_write, 183 .d_ioctl = dead_ioctl, 184 .d_poll = dead_poll, 185 .d_mmap = dead_mmap, 186 .d_strategy = dead_strategy, 187 .d_name = "dead", 188 .d_maj = 255, 189 .d_dump = dead_dump, 190 .d_kqfilter = dead_kqfilter 191 }; 192 193 /* Default methods if driver does not specify method */ 194 195 #define null_open (d_open_t *)nullop 196 #define null_close (d_close_t *)nullop 197 #define no_read (d_read_t *)enodev 198 #define no_write (d_write_t *)enodev 199 #define no_ioctl (d_ioctl_t *)enodev 200 #define no_mmap (d_mmap_t *)enodev 201 202 static int 203 no_kqfilter(struct cdev *dev __unused, struct knote *kn __unused) 204 { 205 206 return (1); 207 } 208 209 static void 210 no_strategy(struct bio *bp) 211 { 212 213 biofinish(bp, NULL, ENODEV); 214 } 215 216 static int 217 no_poll(struct cdev *dev __unused, int events, struct thread *td __unused) 218 { 219 /* 220 * Return true for read/write. If the user asked for something 221 * special, return POLLNVAL, so that clients have a way of 222 * determining reliably whether or not the extended 223 * functionality is present without hard-coding knowledge 224 * of specific filesystem implementations. 225 * Stay in sync with vop_nopoll(). 226 */ 227 if (events & ~POLLSTANDARD) 228 return (POLLNVAL); 229 230 return (events & (POLLIN | POLLOUT | POLLRDNORM | POLLWRNORM)); 231 } 232 233 #define no_dump (dumper_t *)enodev 234 235 struct cdevsw * 236 devsw(struct cdev *dev) 237 { 238 if (dev->si_devsw != NULL) 239 return (dev->si_devsw); 240 return (&dead_cdevsw); 241 } 242 243 /* 244 * struct cdev * and u_dev_t primitives 245 */ 246 247 int 248 major(struct cdev *x) 249 { 250 if (x == NULL) 251 return NODEV; 252 return((x->si_udev >> 8) & 0xff); 253 } 254 255 int 256 minor(struct cdev *x) 257 { 258 if (x == NULL) 259 return NODEV; 260 return(x->si_udev & 0xffff00ff); 261 } 262 263 int 264 dev2unit(struct cdev *x) 265 { 266 int i; 267 268 if (x == NULL) 269 return NODEV; 270 i = minor(x); 271 return ((i & 0xff) | (i >> 8)); 272 } 273 274 int 275 unit2minor(int unit) 276 { 277 278 KASSERT(unit <= 0xffffff, ("Invalid unit (%d) in unit2minor", unit)); 279 return ((unit & 0xff) | ((unit << 8) & ~0xffff)); 280 } 281 282 static struct cdev * 283 allocdev(void) 284 { 285 static int stashed; 286 struct cdev *si; 287 288 if (LIST_FIRST(&dev_free)) { 289 si = LIST_FIRST(&dev_free); 290 LIST_REMOVE(si, si_hash); 291 } else if (stashed >= DEVT_STASH) { 292 MALLOC(si, struct cdev *, sizeof(*si), M_DEVT, 293 M_USE_RESERVE | M_ZERO | M_WAITOK); 294 } else { 295 si = devt_stash + stashed++; 296 bzero(si, sizeof *si); 297 si->si_flags |= SI_STASHED; 298 } 299 si->__si_namebuf[0] = '\0'; 300 si->si_name = si->__si_namebuf; 301 LIST_INIT(&si->si_children); 302 TAILQ_INIT(&si->si_snapshots); 303 return (si); 304 } 305 306 static struct cdev * 307 newdev(int x, int y) 308 { 309 struct cdev *si; 310 dev_t udev; 311 int hash; 312 313 if (x == umajor(NODEV) && y == uminor(NODEV)) 314 panic("newdev of NODEV"); 315 udev = (x << 8) | y; 316 hash = udev % DEVT_HASH; 317 LIST_FOREACH(si, &dev_hash[hash], si_hash) { 318 if (si->si_udev == udev) 319 return (si); 320 } 321 si = allocdev(); 322 si->si_udev = udev; 323 LIST_INSERT_HEAD(&dev_hash[hash], si, si_hash); 324 return (si); 325 } 326 327 static void 328 freedev(struct cdev *dev) 329 { 330 331 if (dev->si_flags & SI_STASHED) { 332 bzero(dev, sizeof(*dev)); 333 dev->si_flags |= SI_STASHED; 334 LIST_INSERT_HEAD(&dev_free, dev, si_hash); 335 } else { 336 FREE(dev, M_DEVT); 337 } 338 } 339 340 dev_t 341 dev2udev(struct cdev *x) 342 { 343 if (x == NULL) 344 return (NODEV); 345 return (x->si_udev); 346 } 347 348 struct cdev * 349 findcdev(dev_t udev) 350 { 351 struct cdev *si; 352 int hash; 353 354 if (udev == NODEV) 355 return (NULL); 356 hash = udev % DEVT_HASH; 357 LIST_FOREACH(si, &dev_hash[hash], si_hash) { 358 if (si->si_udev == udev) 359 return (si); 360 } 361 return (NULL); 362 } 363 364 int 365 uminor(dev_t dev) 366 { 367 return (dev & 0xffff00ff); 368 } 369 370 int 371 umajor(dev_t dev) 372 { 373 return ((dev & 0xff00) >> 8); 374 } 375 376 static void 377 find_major(struct cdevsw *devsw) 378 { 379 int i; 380 381 for (i = NUMCDEVSW - 1; i > 0; i--) 382 if (reserved_majors[i] != i) 383 break; 384 KASSERT(i > 0, ("Out of major numbers (%s)", devsw->d_name)); 385 devsw->d_maj = i; 386 reserved_majors[i] = i; 387 devsw->d_flags |= D_ALLOCMAJ; 388 } 389 390 static void 391 fini_cdevsw(struct cdevsw *devsw) 392 { 393 if (devsw->d_flags & D_ALLOCMAJ) { 394 reserved_majors[devsw->d_maj] = 0; 395 devsw->d_maj = MAJOR_AUTO; 396 devsw->d_flags &= ~D_ALLOCMAJ; 397 } else if (devsw->d_maj == 0) 398 devsw->d_maj = 256; 399 devsw->d_flags &= ~D_INIT; 400 } 401 402 static void 403 prep_cdevsw(struct cdevsw *devsw) 404 { 405 406 devlock(); 407 408 if (devsw->d_version != D_VERSION_00) { 409 printf( 410 "WARNING: Device driver \"%s\" has wrong version %s\n", 411 devsw->d_name, "and is disabled. Recompile KLD module."); 412 devsw->d_open = dead_open; 413 devsw->d_close = dead_close; 414 devsw->d_read = dead_read; 415 devsw->d_write = dead_write; 416 devsw->d_ioctl = dead_ioctl; 417 devsw->d_poll = dead_poll; 418 devsw->d_mmap = dead_mmap; 419 devsw->d_strategy = dead_strategy; 420 devsw->d_dump = dead_dump; 421 devsw->d_kqfilter = dead_kqfilter; 422 } 423 424 if (devsw->d_flags & D_TTY) { 425 if (devsw->d_ioctl == NULL) devsw->d_ioctl = ttyioctl; 426 if (devsw->d_read == NULL) devsw->d_read = ttyread; 427 if (devsw->d_write == NULL) devsw->d_write = ttywrite; 428 if (devsw->d_kqfilter == NULL) devsw->d_kqfilter = ttykqfilter; 429 if (devsw->d_poll == NULL) devsw->d_poll = ttypoll; 430 } 431 432 if (devsw->d_open == NULL) devsw->d_open = null_open; 433 if (devsw->d_close == NULL) devsw->d_close = null_close; 434 if (devsw->d_read == NULL) devsw->d_read = no_read; 435 if (devsw->d_write == NULL) devsw->d_write = no_write; 436 if (devsw->d_ioctl == NULL) devsw->d_ioctl = no_ioctl; 437 if (devsw->d_poll == NULL) devsw->d_poll = no_poll; 438 if (devsw->d_mmap == NULL) devsw->d_mmap = no_mmap; 439 if (devsw->d_strategy == NULL) devsw->d_strategy = no_strategy; 440 if (devsw->d_dump == NULL) devsw->d_dump = no_dump; 441 if (devsw->d_kqfilter == NULL) devsw->d_kqfilter = no_kqfilter; 442 443 LIST_INIT(&devsw->d_devs); 444 445 devsw->d_flags |= D_INIT; 446 447 if (devsw->d_maj == MAJOR_AUTO) { 448 find_major(devsw); 449 } else { 450 if (devsw->d_maj == 256) /* XXX: tty_cons.c is magic */ 451 devsw->d_maj = 0; 452 KASSERT(devsw->d_maj >= 0 && devsw->d_maj < 256, 453 ("Invalid major (%d) in make_dev", devsw->d_maj)); 454 if (reserved_majors[devsw->d_maj] != devsw->d_maj) { 455 printf("WARNING: driver \"%s\" used %s %d\n", 456 devsw->d_name, "unreserved major device number", 457 devsw->d_maj); 458 reserved_majors[devsw->d_maj] = devsw->d_maj; 459 } 460 } 461 devunlock(); 462 } 463 464 struct cdev * 465 make_dev(struct cdevsw *devsw, int minornr, uid_t uid, gid_t gid, int perms, const char *fmt, ...) 466 { 467 struct cdev *dev; 468 va_list ap; 469 int i; 470 471 KASSERT((minornr & ~0xffff00ff) == 0, 472 ("Invalid minor (0x%x) in make_dev", minornr)); 473 474 if (!(devsw->d_flags & D_INIT)) 475 prep_cdevsw(devsw); 476 dev = newdev(devsw->d_maj, minornr); 477 if (dev->si_flags & SI_CHEAPCLONE && 478 dev->si_flags & SI_NAMED && 479 dev->si_devsw == devsw) { 480 /* 481 * This is allowed as it removes races and generally 482 * simplifies cloning devices. 483 * XXX: still ?? 484 */ 485 return (dev); 486 } 487 devlock(); 488 KASSERT(!(dev->si_flags & SI_NAMED), 489 ("make_dev() by driver %s on pre-existing device (maj=%d, min=%d, name=%s)", 490 devsw->d_name, major(dev), minor(dev), devtoname(dev))); 491 492 va_start(ap, fmt); 493 i = vsnrprintf(dev->__si_namebuf, sizeof dev->__si_namebuf, 32, fmt, ap); 494 if (i > (sizeof dev->__si_namebuf - 1)) { 495 printf("WARNING: Device name truncated! (%s)", 496 dev->__si_namebuf); 497 } 498 va_end(ap); 499 dev->si_devsw = devsw; 500 dev->si_uid = uid; 501 dev->si_gid = gid; 502 dev->si_mode = perms; 503 dev->si_flags |= SI_NAMED; 504 505 LIST_INSERT_HEAD(&devsw->d_devs, dev, si_list); 506 devfs_create(dev); 507 devunlock(); 508 return (dev); 509 } 510 511 int 512 dev_named(struct cdev *pdev, const char *name) 513 { 514 struct cdev *cdev; 515 516 if (strcmp(devtoname(pdev), name) == 0) 517 return (1); 518 LIST_FOREACH(cdev, &pdev->si_children, si_siblings) 519 if (strcmp(devtoname(cdev), name) == 0) 520 return (1); 521 return (0); 522 } 523 524 void 525 dev_depends(struct cdev *pdev, struct cdev *cdev) 526 { 527 528 devlock(); 529 cdev->si_parent = pdev; 530 cdev->si_flags |= SI_CHILD; 531 LIST_INSERT_HEAD(&pdev->si_children, cdev, si_siblings); 532 devunlock(); 533 } 534 535 struct cdev * 536 make_dev_alias(struct cdev *pdev, const char *fmt, ...) 537 { 538 struct cdev *dev; 539 va_list ap; 540 int i; 541 542 dev = allocdev(); 543 devlock(); 544 dev->si_flags |= SI_ALIAS; 545 dev->si_flags |= SI_NAMED; 546 va_start(ap, fmt); 547 i = vsnrprintf(dev->__si_namebuf, sizeof dev->__si_namebuf, 32, fmt, ap); 548 if (i > (sizeof dev->__si_namebuf - 1)) { 549 printf("WARNING: Device name truncated! (%s)", 550 dev->__si_namebuf); 551 } 552 va_end(ap); 553 554 devfs_create(dev); 555 devunlock(); 556 dev_depends(pdev, dev); 557 return (dev); 558 } 559 560 static void 561 idestroy_dev(struct cdev *dev) 562 { 563 if (!(dev->si_flags & SI_NAMED)) { 564 printf( "WARNING: Driver mistake: destroy_dev on %d/%d\n", 565 major(dev), minor(dev)); 566 panic("don't do that"); 567 } 568 569 devfs_destroy(dev); 570 571 /* Remove name marking */ 572 dev->si_flags &= ~SI_NAMED; 573 574 /* If we are a child, remove us from the parents list */ 575 if (dev->si_flags & SI_CHILD) { 576 LIST_REMOVE(dev, si_siblings); 577 dev->si_flags &= ~SI_CHILD; 578 } 579 580 /* Kill our children */ 581 while (!LIST_EMPTY(&dev->si_children)) 582 idestroy_dev(LIST_FIRST(&dev->si_children)); 583 584 /* Remove from clone list */ 585 if (dev->si_flags & SI_CLONELIST) { 586 LIST_REMOVE(dev, si_clone); 587 dev->si_flags &= ~SI_CLONELIST; 588 } 589 590 if (!(dev->si_flags & SI_ALIAS)) { 591 /* Remove from cdevsw list */ 592 LIST_REMOVE(dev, si_list); 593 594 /* If cdevsw has no struct cdev *'s, clean it */ 595 if (LIST_EMPTY(&dev->si_devsw->d_devs)) 596 fini_cdevsw(dev->si_devsw); 597 598 LIST_REMOVE(dev, si_hash); 599 } 600 dev->si_drv1 = 0; 601 dev->si_drv2 = 0; 602 dev->si_devsw = NULL; 603 bzero(&dev->__si_u, sizeof(dev->__si_u)); 604 dev->si_flags &= ~SI_ALIAS; 605 if (dev->si_refcount > 0) { 606 LIST_INSERT_HEAD(&dead_cdevsw.d_devs, dev, si_list); 607 } else { 608 freedev(dev); 609 } 610 } 611 612 void 613 destroy_dev(struct cdev *dev) 614 { 615 616 devlock(); 617 idestroy_dev(dev); 618 devunlock(); 619 } 620 621 const char * 622 devtoname(struct cdev *dev) 623 { 624 char *p; 625 int mynor; 626 627 if (dev->si_name[0] == '#' || dev->si_name[0] == '\0') { 628 p = dev->si_name; 629 if (devsw(dev)) 630 sprintf(p, "#%s/", devsw(dev)->d_name); 631 else 632 sprintf(p, "#%d/", major(dev)); 633 p += strlen(p); 634 mynor = minor(dev); 635 if (mynor < 0 || mynor > 255) 636 sprintf(p, "%#x", (u_int)mynor); 637 else 638 sprintf(p, "%d", mynor); 639 } 640 return (dev->si_name); 641 } 642 643 int 644 dev_stdclone(char *name, char **namep, const char *stem, int *unit) 645 { 646 int u, i; 647 648 i = strlen(stem); 649 if (bcmp(stem, name, i) != 0) 650 return (0); 651 if (!isdigit(name[i])) 652 return (0); 653 u = 0; 654 if (name[i] == '0' && isdigit(name[i+1])) 655 return (0); 656 while (isdigit(name[i])) { 657 u *= 10; 658 u += name[i++] - '0'; 659 } 660 if (u > 0xffffff) 661 return (0); 662 *unit = u; 663 if (namep) 664 *namep = &name[i]; 665 if (name[i]) 666 return (2); 667 return (1); 668 } 669 670 /* 671 * Helper functions for cloning device drivers. 672 * 673 * The objective here is to make it unnecessary for the device drivers to 674 * use rman or similar to manage their unit number space. Due to the way 675 * we do "on-demand" devices, using rman or other "private" methods 676 * will be very tricky to lock down properly once we lock down this file. 677 * 678 * Instead we give the drivers these routines which puts the struct cdev *'s 679 * that are to be managed on their own list, and gives the driver the ability 680 * to ask for the first free unit number or a given specified unit number. 681 * 682 * In addition these routines support paired devices (pty, nmdm and similar) 683 * by respecting a number of "flag" bits in the minor number. 684 * 685 */ 686 687 struct clonedevs { 688 LIST_HEAD(,cdev) head; 689 }; 690 691 void 692 clone_setup(struct clonedevs **cdp) 693 { 694 695 *cdp = malloc(sizeof **cdp, M_DEVBUF, M_WAITOK | M_ZERO); 696 LIST_INIT(&(*cdp)->head); 697 } 698 699 int 700 clone_create(struct clonedevs **cdp, struct cdevsw *csw, int *up, struct cdev **dp, u_int extra) 701 { 702 struct clonedevs *cd; 703 struct cdev *dev, *dl, *de; 704 int unit, low, u; 705 706 KASSERT(*cdp != NULL, 707 ("clone_setup() not called in driver \"%s\"", csw->d_name)); 708 KASSERT(!(extra & CLONE_UNITMASK), 709 ("Illegal extra bits (0x%x) in clone_create", extra)); 710 KASSERT(*up <= CLONE_UNITMASK, 711 ("Too high unit (0x%x) in clone_create", *up)); 712 713 if (csw->d_maj == MAJOR_AUTO) 714 find_major(csw); 715 716 /* 717 * Search the list for a lot of things in one go: 718 * A preexisting match is returned immediately. 719 * The lowest free unit number if we are passed -1, and the place 720 * in the list where we should insert that new element. 721 * The place to insert a specified unit number, if applicable 722 * the end of the list. 723 */ 724 unit = *up; 725 low = extra; 726 de = dl = NULL; 727 cd = *cdp; 728 LIST_FOREACH(dev, &cd->head, si_clone) { 729 u = dev2unit(dev); 730 if (u == (unit | extra)) { 731 *dp = dev; 732 return (0); 733 } 734 if (unit == -1 && u == low) { 735 low++; 736 de = dev; 737 continue; 738 } 739 if (u > (unit | extra)) { 740 dl = dev; 741 break; 742 } 743 de = dev; 744 } 745 if (unit == -1) 746 unit = low & CLONE_UNITMASK; 747 dev = newdev(csw->d_maj, unit2minor(unit | extra)); 748 KASSERT(!(dev->si_flags & SI_CLONELIST), 749 ("Dev %p should not be on clonelist", dev)); 750 if (dl != NULL) 751 LIST_INSERT_BEFORE(dl, dev, si_clone); 752 else if (de != NULL) 753 LIST_INSERT_AFTER(de, dev, si_clone); 754 else 755 LIST_INSERT_HEAD(&cd->head, dev, si_clone); 756 dev->si_flags |= SI_CLONELIST; 757 *up = unit; 758 return (1); 759 } 760 761 /* 762 * Kill everything still on the list. The driver should already have 763 * disposed of any softc hung of the struct cdev *'s at this time. 764 */ 765 void 766 clone_cleanup(struct clonedevs **cdp) 767 { 768 struct cdev *dev, *tdev; 769 struct clonedevs *cd; 770 771 cd = *cdp; 772 if (cd == NULL) 773 return; 774 LIST_FOREACH_SAFE(dev, &cd->head, si_clone, tdev) { 775 KASSERT(dev->si_flags & SI_NAMED, 776 ("Driver has goofed in cloning underways udev %x", dev->si_udev)); 777 destroy_dev(dev); 778 } 779 free(cd, M_DEVBUF); 780 *cdp = NULL; 781 } 782 783 /* 784 * Helper sysctl for devname(3). We're given a struct cdev * and return 785 * the name, if any, registered by the device driver. 786 */ 787 static int 788 sysctl_devname(SYSCTL_HANDLER_ARGS) 789 { 790 int error; 791 dev_t ud; 792 struct cdev *dev; 793 794 error = SYSCTL_IN(req, &ud, sizeof (ud)); 795 if (error) 796 return (error); 797 if (ud == NODEV) 798 return(EINVAL); 799 dev = findcdev(ud); 800 if (dev == NULL) 801 error = ENOENT; 802 else 803 error = SYSCTL_OUT(req, dev->si_name, strlen(dev->si_name) + 1); 804 return (error); 805 } 806 807 SYSCTL_PROC(_kern, OID_AUTO, devname, CTLTYPE_OPAQUE|CTLFLAG_RW|CTLFLAG_ANYBODY, 808 NULL, 0, sysctl_devname, "", "devname(3) handler"); 809