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 #define no_kqfilter (d_kqfilter_t *)enodev 202 203 static void 204 no_strategy(struct bio *bp) 205 { 206 207 biofinish(bp, NULL, ENODEV); 208 } 209 210 static int 211 no_poll(struct cdev *dev __unused, int events, struct thread *td __unused) 212 { 213 /* 214 * Return true for read/write. If the user asked for something 215 * special, return POLLNVAL, so that clients have a way of 216 * determining reliably whether or not the extended 217 * functionality is present without hard-coding knowledge 218 * of specific filesystem implementations. 219 * Stay in sync with vop_nopoll(). 220 */ 221 if (events & ~POLLSTANDARD) 222 return (POLLNVAL); 223 224 return (events & (POLLIN | POLLOUT | POLLRDNORM | POLLWRNORM)); 225 } 226 227 #define no_dump (dumper_t *)enodev 228 229 struct cdevsw * 230 devsw(struct cdev *dev) 231 { 232 if (dev->si_devsw != NULL) 233 return (dev->si_devsw); 234 return (&dead_cdevsw); 235 } 236 237 /* 238 * struct cdev * and u_dev_t primitives 239 */ 240 241 int 242 major(struct cdev *x) 243 { 244 if (x == NULL) 245 return NODEV; 246 return((x->si_udev >> 8) & 0xff); 247 } 248 249 int 250 minor(struct cdev *x) 251 { 252 if (x == NULL) 253 return NODEV; 254 return(x->si_udev & 0xffff00ff); 255 } 256 257 int 258 dev2unit(struct cdev *x) 259 { 260 int i; 261 262 if (x == NULL) 263 return NODEV; 264 i = minor(x); 265 return ((i & 0xff) | (i >> 8)); 266 } 267 268 int 269 unit2minor(int unit) 270 { 271 272 KASSERT(unit <= 0xffffff, ("Invalid unit (%d) in unit2minor", unit)); 273 return ((unit & 0xff) | ((unit << 8) & ~0xffff)); 274 } 275 276 static struct cdev * 277 allocdev(void) 278 { 279 static int stashed; 280 struct cdev *si; 281 282 if (LIST_FIRST(&dev_free)) { 283 si = LIST_FIRST(&dev_free); 284 LIST_REMOVE(si, si_hash); 285 } else if (stashed >= DEVT_STASH) { 286 MALLOC(si, struct cdev *, sizeof(*si), M_DEVT, 287 M_USE_RESERVE | M_ZERO | M_WAITOK); 288 } else { 289 si = devt_stash + stashed++; 290 bzero(si, sizeof *si); 291 si->si_flags |= SI_STASHED; 292 } 293 si->__si_namebuf[0] = '\0'; 294 si->si_name = si->__si_namebuf; 295 LIST_INIT(&si->si_children); 296 return (si); 297 } 298 299 static struct cdev * 300 newdev(int x, int y) 301 { 302 struct cdev *si; 303 dev_t udev; 304 int hash; 305 306 if (x == umajor(NODEV) && y == uminor(NODEV)) 307 panic("newdev of NODEV"); 308 udev = (x << 8) | y; 309 hash = udev % DEVT_HASH; 310 LIST_FOREACH(si, &dev_hash[hash], si_hash) { 311 if (si->si_udev == udev) 312 return (si); 313 } 314 si = allocdev(); 315 si->si_udev = udev; 316 LIST_INSERT_HEAD(&dev_hash[hash], si, si_hash); 317 return (si); 318 } 319 320 static void 321 freedev(struct cdev *dev) 322 { 323 324 if (dev->si_flags & SI_STASHED) { 325 bzero(dev, sizeof(*dev)); 326 dev->si_flags |= SI_STASHED; 327 LIST_INSERT_HEAD(&dev_free, dev, si_hash); 328 } else { 329 FREE(dev, M_DEVT); 330 } 331 } 332 333 dev_t 334 dev2udev(struct cdev *x) 335 { 336 if (x == NULL) 337 return (NODEV); 338 return (x->si_udev); 339 } 340 341 struct cdev * 342 findcdev(dev_t udev) 343 { 344 struct cdev *si; 345 int hash; 346 347 if (udev == NODEV) 348 return (NULL); 349 hash = udev % DEVT_HASH; 350 LIST_FOREACH(si, &dev_hash[hash], si_hash) { 351 if (si->si_udev == udev) 352 return (si); 353 } 354 return (NULL); 355 } 356 357 int 358 uminor(dev_t dev) 359 { 360 return (dev & 0xffff00ff); 361 } 362 363 int 364 umajor(dev_t dev) 365 { 366 return ((dev & 0xff00) >> 8); 367 } 368 369 static void 370 find_major(struct cdevsw *devsw) 371 { 372 int i; 373 374 for (i = NUMCDEVSW - 1; i > 0; i--) 375 if (reserved_majors[i] != i) 376 break; 377 KASSERT(i > 0, ("Out of major numbers (%s)", devsw->d_name)); 378 devsw->d_maj = i; 379 reserved_majors[i] = i; 380 devsw->d_flags |= D_ALLOCMAJ; 381 } 382 383 static void 384 fini_cdevsw(struct cdevsw *devsw) 385 { 386 if (devsw->d_flags & D_ALLOCMAJ) { 387 reserved_majors[devsw->d_maj] = 0; 388 devsw->d_maj = MAJOR_AUTO; 389 devsw->d_flags &= ~D_ALLOCMAJ; 390 } else if (devsw->d_maj == 0) 391 devsw->d_maj = 256; 392 devsw->d_flags &= ~D_INIT; 393 } 394 395 static void 396 prep_cdevsw(struct cdevsw *devsw) 397 { 398 399 devlock(); 400 401 if (devsw->d_version != D_VERSION_00) { 402 printf( 403 "WARNING: Device driver \"%s\" has wrong version %s\n", 404 devsw->d_name, "and is disabled. Recompile KLD module."); 405 devsw->d_open = dead_open; 406 devsw->d_close = dead_close; 407 devsw->d_read = dead_read; 408 devsw->d_write = dead_write; 409 devsw->d_ioctl = dead_ioctl; 410 devsw->d_poll = dead_poll; 411 devsw->d_mmap = dead_mmap; 412 devsw->d_strategy = dead_strategy; 413 devsw->d_dump = dead_dump; 414 devsw->d_kqfilter = dead_kqfilter; 415 } 416 417 if (devsw->d_flags & D_TTY) { 418 if (devsw->d_ioctl == NULL) devsw->d_ioctl = ttyioctl; 419 if (devsw->d_read == NULL) devsw->d_read = ttyread; 420 if (devsw->d_write == NULL) devsw->d_write = ttywrite; 421 if (devsw->d_kqfilter == NULL) devsw->d_kqfilter = ttykqfilter; 422 if (devsw->d_poll == NULL) devsw->d_poll = ttypoll; 423 } 424 425 if (devsw->d_open == NULL) devsw->d_open = null_open; 426 if (devsw->d_close == NULL) devsw->d_close = null_close; 427 if (devsw->d_read == NULL) devsw->d_read = no_read; 428 if (devsw->d_write == NULL) devsw->d_write = no_write; 429 if (devsw->d_ioctl == NULL) devsw->d_ioctl = no_ioctl; 430 if (devsw->d_poll == NULL) devsw->d_poll = no_poll; 431 if (devsw->d_mmap == NULL) devsw->d_mmap = no_mmap; 432 if (devsw->d_strategy == NULL) devsw->d_strategy = no_strategy; 433 if (devsw->d_dump == NULL) devsw->d_dump = no_dump; 434 if (devsw->d_kqfilter == NULL) devsw->d_kqfilter = no_kqfilter; 435 436 LIST_INIT(&devsw->d_devs); 437 438 devsw->d_flags |= D_INIT; 439 440 if (devsw->d_maj == MAJOR_AUTO) { 441 find_major(devsw); 442 } else { 443 if (devsw->d_maj == 256) /* XXX: tty_cons.c is magic */ 444 devsw->d_maj = 0; 445 KASSERT(devsw->d_maj >= 0 && devsw->d_maj < 256, 446 ("Invalid major (%d) in make_dev", devsw->d_maj)); 447 if (reserved_majors[devsw->d_maj] != devsw->d_maj) { 448 printf("WARNING: driver \"%s\" used %s %d\n", 449 devsw->d_name, "unreserved major device number", 450 devsw->d_maj); 451 reserved_majors[devsw->d_maj] = devsw->d_maj; 452 } 453 } 454 devunlock(); 455 } 456 457 struct cdev * 458 make_dev(struct cdevsw *devsw, int minornr, uid_t uid, gid_t gid, int perms, const char *fmt, ...) 459 { 460 struct cdev *dev; 461 va_list ap; 462 int i; 463 464 KASSERT((minornr & ~0xffff00ff) == 0, 465 ("Invalid minor (0x%x) in make_dev", minornr)); 466 467 if (!(devsw->d_flags & D_INIT)) 468 prep_cdevsw(devsw); 469 dev = newdev(devsw->d_maj, minornr); 470 if (dev->si_flags & SI_CHEAPCLONE && 471 dev->si_flags & SI_NAMED && 472 dev->si_devsw == devsw) { 473 /* 474 * This is allowed as it removes races and generally 475 * simplifies cloning devices. 476 * XXX: still ?? 477 */ 478 return (dev); 479 } 480 devlock(); 481 KASSERT(!(dev->si_flags & SI_NAMED), 482 ("make_dev() by driver %s on pre-existing device (maj=%d, min=%d, name=%s)", 483 devsw->d_name, major(dev), minor(dev), devtoname(dev))); 484 485 va_start(ap, fmt); 486 i = vsnrprintf(dev->__si_namebuf, sizeof dev->__si_namebuf, 32, fmt, ap); 487 if (i > (sizeof dev->__si_namebuf - 1)) { 488 printf("WARNING: Device name truncated! (%s)\n", 489 dev->__si_namebuf); 490 } 491 va_end(ap); 492 dev->si_devsw = devsw; 493 dev->si_uid = uid; 494 dev->si_gid = gid; 495 dev->si_mode = perms; 496 dev->si_flags |= SI_NAMED; 497 498 LIST_INSERT_HEAD(&devsw->d_devs, dev, si_list); 499 devfs_create(dev); 500 devunlock(); 501 return (dev); 502 } 503 504 int 505 dev_named(struct cdev *pdev, const char *name) 506 { 507 struct cdev *cdev; 508 509 if (strcmp(devtoname(pdev), name) == 0) 510 return (1); 511 LIST_FOREACH(cdev, &pdev->si_children, si_siblings) 512 if (strcmp(devtoname(cdev), name) == 0) 513 return (1); 514 return (0); 515 } 516 517 void 518 dev_depends(struct cdev *pdev, struct cdev *cdev) 519 { 520 521 devlock(); 522 cdev->si_parent = pdev; 523 cdev->si_flags |= SI_CHILD; 524 LIST_INSERT_HEAD(&pdev->si_children, cdev, si_siblings); 525 devunlock(); 526 } 527 528 struct cdev * 529 make_dev_alias(struct cdev *pdev, const char *fmt, ...) 530 { 531 struct cdev *dev; 532 va_list ap; 533 int i; 534 535 dev = allocdev(); 536 devlock(); 537 dev->si_flags |= SI_ALIAS; 538 dev->si_flags |= SI_NAMED; 539 va_start(ap, fmt); 540 i = vsnrprintf(dev->__si_namebuf, sizeof dev->__si_namebuf, 32, fmt, ap); 541 if (i > (sizeof dev->__si_namebuf - 1)) { 542 printf("WARNING: Device name truncated! (%s)\n", 543 dev->__si_namebuf); 544 } 545 va_end(ap); 546 547 devfs_create(dev); 548 devunlock(); 549 dev_depends(pdev, dev); 550 return (dev); 551 } 552 553 static void 554 idestroy_dev(struct cdev *dev) 555 { 556 if (!(dev->si_flags & SI_NAMED)) { 557 printf( "WARNING: Driver mistake: destroy_dev on %d/%d\n", 558 major(dev), minor(dev)); 559 panic("don't do that"); 560 } 561 562 devfs_destroy(dev); 563 564 /* Remove name marking */ 565 dev->si_flags &= ~SI_NAMED; 566 567 /* If we are a child, remove us from the parents list */ 568 if (dev->si_flags & SI_CHILD) { 569 LIST_REMOVE(dev, si_siblings); 570 dev->si_flags &= ~SI_CHILD; 571 } 572 573 /* Kill our children */ 574 while (!LIST_EMPTY(&dev->si_children)) 575 idestroy_dev(LIST_FIRST(&dev->si_children)); 576 577 /* Remove from clone list */ 578 if (dev->si_flags & SI_CLONELIST) { 579 LIST_REMOVE(dev, si_clone); 580 dev->si_flags &= ~SI_CLONELIST; 581 } 582 583 if (!(dev->si_flags & SI_ALIAS)) { 584 /* Remove from cdevsw list */ 585 LIST_REMOVE(dev, si_list); 586 587 /* If cdevsw has no struct cdev *'s, clean it */ 588 if (LIST_EMPTY(&dev->si_devsw->d_devs)) 589 fini_cdevsw(dev->si_devsw); 590 591 LIST_REMOVE(dev, si_hash); 592 } 593 dev->si_drv1 = 0; 594 dev->si_drv2 = 0; 595 dev->si_devsw = NULL; 596 bzero(&dev->__si_u, sizeof(dev->__si_u)); 597 dev->si_flags &= ~SI_ALIAS; 598 if (dev->si_refcount > 0) { 599 LIST_INSERT_HEAD(&dead_cdevsw.d_devs, dev, si_list); 600 } else { 601 freedev(dev); 602 } 603 } 604 605 void 606 destroy_dev(struct cdev *dev) 607 { 608 609 devlock(); 610 idestroy_dev(dev); 611 devunlock(); 612 } 613 614 const char * 615 devtoname(struct cdev *dev) 616 { 617 char *p; 618 int mynor; 619 620 if (dev->si_name[0] == '#' || dev->si_name[0] == '\0') { 621 p = dev->si_name; 622 if (devsw(dev)) 623 sprintf(p, "#%s/", devsw(dev)->d_name); 624 else 625 sprintf(p, "#%d/", major(dev)); 626 p += strlen(p); 627 mynor = minor(dev); 628 if (mynor < 0 || mynor > 255) 629 sprintf(p, "%#x", (u_int)mynor); 630 else 631 sprintf(p, "%d", mynor); 632 } 633 return (dev->si_name); 634 } 635 636 int 637 dev_stdclone(char *name, char **namep, const char *stem, int *unit) 638 { 639 int u, i; 640 641 i = strlen(stem); 642 if (bcmp(stem, name, i) != 0) 643 return (0); 644 if (!isdigit(name[i])) 645 return (0); 646 u = 0; 647 if (name[i] == '0' && isdigit(name[i+1])) 648 return (0); 649 while (isdigit(name[i])) { 650 u *= 10; 651 u += name[i++] - '0'; 652 } 653 if (u > 0xffffff) 654 return (0); 655 *unit = u; 656 if (namep) 657 *namep = &name[i]; 658 if (name[i]) 659 return (2); 660 return (1); 661 } 662 663 /* 664 * Helper functions for cloning device drivers. 665 * 666 * The objective here is to make it unnecessary for the device drivers to 667 * use rman or similar to manage their unit number space. Due to the way 668 * we do "on-demand" devices, using rman or other "private" methods 669 * will be very tricky to lock down properly once we lock down this file. 670 * 671 * Instead we give the drivers these routines which puts the struct cdev *'s 672 * that are to be managed on their own list, and gives the driver the ability 673 * to ask for the first free unit number or a given specified unit number. 674 * 675 * In addition these routines support paired devices (pty, nmdm and similar) 676 * by respecting a number of "flag" bits in the minor number. 677 * 678 */ 679 680 struct clonedevs { 681 LIST_HEAD(,cdev) head; 682 }; 683 684 void 685 clone_setup(struct clonedevs **cdp) 686 { 687 688 *cdp = malloc(sizeof **cdp, M_DEVBUF, M_WAITOK | M_ZERO); 689 LIST_INIT(&(*cdp)->head); 690 } 691 692 int 693 clone_create(struct clonedevs **cdp, struct cdevsw *csw, int *up, struct cdev **dp, u_int extra) 694 { 695 struct clonedevs *cd; 696 struct cdev *dev, *dl, *de; 697 int unit, low, u; 698 699 KASSERT(*cdp != NULL, 700 ("clone_setup() not called in driver \"%s\"", csw->d_name)); 701 KASSERT(!(extra & CLONE_UNITMASK), 702 ("Illegal extra bits (0x%x) in clone_create", extra)); 703 KASSERT(*up <= CLONE_UNITMASK, 704 ("Too high unit (0x%x) in clone_create", *up)); 705 706 if (csw->d_maj == MAJOR_AUTO) 707 find_major(csw); 708 709 /* 710 * Search the list for a lot of things in one go: 711 * A preexisting match is returned immediately. 712 * The lowest free unit number if we are passed -1, and the place 713 * in the list where we should insert that new element. 714 * The place to insert a specified unit number, if applicable 715 * the end of the list. 716 */ 717 unit = *up; 718 low = extra; 719 de = dl = NULL; 720 cd = *cdp; 721 LIST_FOREACH(dev, &cd->head, si_clone) { 722 u = dev2unit(dev); 723 if (u == (unit | extra)) { 724 *dp = dev; 725 return (0); 726 } 727 if (unit == -1 && u == low) { 728 low++; 729 de = dev; 730 continue; 731 } 732 if (u > (unit | extra)) { 733 dl = dev; 734 break; 735 } 736 de = dev; 737 } 738 if (unit == -1) 739 unit = low & CLONE_UNITMASK; 740 dev = newdev(csw->d_maj, unit2minor(unit | extra)); 741 KASSERT(!(dev->si_flags & SI_CLONELIST), 742 ("Dev %p should not be on clonelist", dev)); 743 if (dl != NULL) 744 LIST_INSERT_BEFORE(dl, dev, si_clone); 745 else if (de != NULL) 746 LIST_INSERT_AFTER(de, dev, si_clone); 747 else 748 LIST_INSERT_HEAD(&cd->head, dev, si_clone); 749 dev->si_flags |= SI_CLONELIST; 750 *up = unit; 751 return (1); 752 } 753 754 /* 755 * Kill everything still on the list. The driver should already have 756 * disposed of any softc hung of the struct cdev *'s at this time. 757 */ 758 void 759 clone_cleanup(struct clonedevs **cdp) 760 { 761 struct cdev *dev, *tdev; 762 struct clonedevs *cd; 763 764 cd = *cdp; 765 if (cd == NULL) 766 return; 767 LIST_FOREACH_SAFE(dev, &cd->head, si_clone, tdev) { 768 KASSERT(dev->si_flags & SI_NAMED, 769 ("Driver has goofed in cloning underways udev %x", dev->si_udev)); 770 destroy_dev(dev); 771 } 772 free(cd, M_DEVBUF); 773 *cdp = NULL; 774 } 775 776 /* 777 * Helper sysctl for devname(3). We're given a struct cdev * and return 778 * the name, if any, registered by the device driver. 779 */ 780 static int 781 sysctl_devname(SYSCTL_HANDLER_ARGS) 782 { 783 int error; 784 dev_t ud; 785 struct cdev *dev; 786 787 error = SYSCTL_IN(req, &ud, sizeof (ud)); 788 if (error) 789 return (error); 790 if (ud == NODEV) 791 return(EINVAL); 792 dev = findcdev(ud); 793 if (dev == NULL) 794 error = ENOENT; 795 else 796 error = SYSCTL_OUT(req, dev->si_name, strlen(dev->si_name) + 1); 797 return (error); 798 } 799 800 SYSCTL_PROC(_kern, OID_AUTO, devname, CTLTYPE_OPAQUE|CTLFLAG_RW|CTLFLAG_ANYBODY, 801 NULL, 0, sysctl_devname, "", "devname(3) handler"); 802