1 /*- 2 * SPDX-License-Identifier: BSD-2-Clause-FreeBSD 3 * 4 * Copyright (c) 1999-2002 Poul-Henning Kamp 5 * All rights reserved. 6 * 7 * Redistribution and use in source and binary forms, with or without 8 * modification, are permitted provided that the following conditions 9 * are met: 10 * 1. Redistributions of source code must retain the above copyright 11 * notice, this list of conditions and the following disclaimer. 12 * 2. Redistributions in binary form must reproduce the above copyright 13 * notice, this list of conditions and the following disclaimer in the 14 * documentation and/or other materials provided with the distribution. 15 * 16 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 17 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 18 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 19 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 20 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 21 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 22 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 23 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 24 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 25 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 26 * SUCH DAMAGE. 27 */ 28 29 #include <sys/cdefs.h> 30 __FBSDID("$FreeBSD$"); 31 32 #include <sys/param.h> 33 #include <sys/kernel.h> 34 #include <sys/systm.h> 35 #include <sys/bus.h> 36 #include <sys/bio.h> 37 #include <sys/lock.h> 38 #include <sys/mutex.h> 39 #include <sys/module.h> 40 #include <sys/malloc.h> 41 #include <sys/conf.h> 42 #include <sys/vnode.h> 43 #include <sys/queue.h> 44 #include <sys/poll.h> 45 #include <sys/sx.h> 46 #include <sys/ctype.h> 47 #include <sys/ucred.h> 48 #include <sys/taskqueue.h> 49 #include <machine/stdarg.h> 50 51 #include <fs/devfs/devfs_int.h> 52 #include <vm/vm.h> 53 54 static MALLOC_DEFINE(M_DEVT, "cdev", "cdev storage"); 55 56 struct mtx devmtx; 57 static void destroy_devl(struct cdev *dev); 58 static int destroy_dev_sched_cbl(struct cdev *dev, 59 void (*cb)(void *), void *arg); 60 static void destroy_dev_tq(void *ctx, int pending); 61 static int make_dev_credv(int flags, struct cdev **dres, struct cdevsw *devsw, 62 int unit, struct ucred *cr, uid_t uid, gid_t gid, int mode, const char *fmt, 63 va_list ap); 64 65 static struct cdev_priv_list cdevp_free_list = 66 TAILQ_HEAD_INITIALIZER(cdevp_free_list); 67 static SLIST_HEAD(free_cdevsw, cdevsw) cdevsw_gt_post_list = 68 SLIST_HEAD_INITIALIZER(cdevsw_gt_post_list); 69 70 void 71 dev_lock(void) 72 { 73 74 mtx_lock(&devmtx); 75 } 76 77 /* 78 * Free all the memory collected while the cdev mutex was 79 * locked. Since devmtx is after the system map mutex, free() cannot 80 * be called immediately and is postponed until cdev mutex can be 81 * dropped. 82 */ 83 static void 84 dev_unlock_and_free(void) 85 { 86 struct cdev_priv_list cdp_free; 87 struct free_cdevsw csw_free; 88 struct cdev_priv *cdp; 89 struct cdevsw *csw; 90 91 mtx_assert(&devmtx, MA_OWNED); 92 93 /* 94 * Make the local copy of the list heads while the dev_mtx is 95 * held. Free it later. 96 */ 97 TAILQ_INIT(&cdp_free); 98 TAILQ_CONCAT(&cdp_free, &cdevp_free_list, cdp_list); 99 csw_free = cdevsw_gt_post_list; 100 SLIST_INIT(&cdevsw_gt_post_list); 101 102 mtx_unlock(&devmtx); 103 104 while ((cdp = TAILQ_FIRST(&cdp_free)) != NULL) { 105 TAILQ_REMOVE(&cdp_free, cdp, cdp_list); 106 devfs_free(&cdp->cdp_c); 107 } 108 while ((csw = SLIST_FIRST(&csw_free)) != NULL) { 109 SLIST_REMOVE_HEAD(&csw_free, d_postfree_list); 110 free(csw, M_DEVT); 111 } 112 } 113 114 static void 115 dev_free_devlocked(struct cdev *cdev) 116 { 117 struct cdev_priv *cdp; 118 119 mtx_assert(&devmtx, MA_OWNED); 120 cdp = cdev2priv(cdev); 121 KASSERT((cdp->cdp_flags & CDP_UNREF_DTR) == 0, 122 ("destroy_dev() was not called after delist_dev(%p)", cdev)); 123 TAILQ_INSERT_HEAD(&cdevp_free_list, cdp, cdp_list); 124 } 125 126 static void 127 cdevsw_free_devlocked(struct cdevsw *csw) 128 { 129 130 mtx_assert(&devmtx, MA_OWNED); 131 SLIST_INSERT_HEAD(&cdevsw_gt_post_list, csw, d_postfree_list); 132 } 133 134 void 135 dev_unlock(void) 136 { 137 138 mtx_unlock(&devmtx); 139 } 140 141 void 142 dev_ref(struct cdev *dev) 143 { 144 145 mtx_assert(&devmtx, MA_NOTOWNED); 146 mtx_lock(&devmtx); 147 dev->si_refcount++; 148 mtx_unlock(&devmtx); 149 } 150 151 void 152 dev_refl(struct cdev *dev) 153 { 154 155 mtx_assert(&devmtx, MA_OWNED); 156 dev->si_refcount++; 157 } 158 159 void 160 dev_rel(struct cdev *dev) 161 { 162 int flag = 0; 163 164 mtx_assert(&devmtx, MA_NOTOWNED); 165 dev_lock(); 166 dev->si_refcount--; 167 KASSERT(dev->si_refcount >= 0, 168 ("dev_rel(%s) gave negative count", devtoname(dev))); 169 #if 0 170 if (dev->si_usecount == 0 && 171 (dev->si_flags & SI_CHEAPCLONE) && (dev->si_flags & SI_NAMED)) 172 ; 173 else 174 #endif 175 if (dev->si_devsw == NULL && dev->si_refcount == 0) { 176 LIST_REMOVE(dev, si_list); 177 flag = 1; 178 } 179 dev_unlock(); 180 if (flag) 181 devfs_free(dev); 182 } 183 184 struct cdevsw * 185 dev_refthread(struct cdev *dev, int *ref) 186 { 187 struct cdevsw *csw; 188 struct cdev_priv *cdp; 189 190 mtx_assert(&devmtx, MA_NOTOWNED); 191 if ((dev->si_flags & SI_ETERNAL) != 0) { 192 *ref = 0; 193 return (dev->si_devsw); 194 } 195 dev_lock(); 196 csw = dev->si_devsw; 197 if (csw != NULL) { 198 cdp = cdev2priv(dev); 199 if ((cdp->cdp_flags & CDP_SCHED_DTR) == 0) 200 atomic_add_long(&dev->si_threadcount, 1); 201 else 202 csw = NULL; 203 } 204 dev_unlock(); 205 if (csw != NULL) 206 *ref = 1; 207 return (csw); 208 } 209 210 struct cdevsw * 211 devvn_refthread(struct vnode *vp, struct cdev **devp, int *ref) 212 { 213 struct cdevsw *csw; 214 struct cdev_priv *cdp; 215 struct cdev *dev; 216 217 mtx_assert(&devmtx, MA_NOTOWNED); 218 if ((vp->v_vflag & VV_ETERNALDEV) != 0) { 219 dev = vp->v_rdev; 220 if (dev == NULL) 221 return (NULL); 222 KASSERT((dev->si_flags & SI_ETERNAL) != 0, 223 ("Not eternal cdev")); 224 *ref = 0; 225 csw = dev->si_devsw; 226 KASSERT(csw != NULL, ("Eternal cdev is destroyed")); 227 *devp = dev; 228 return (csw); 229 } 230 231 csw = NULL; 232 dev_lock(); 233 dev = vp->v_rdev; 234 if (dev == NULL) { 235 dev_unlock(); 236 return (NULL); 237 } 238 cdp = cdev2priv(dev); 239 if ((cdp->cdp_flags & CDP_SCHED_DTR) == 0) { 240 csw = dev->si_devsw; 241 if (csw != NULL) 242 atomic_add_long(&dev->si_threadcount, 1); 243 } 244 dev_unlock(); 245 if (csw != NULL) { 246 *devp = dev; 247 *ref = 1; 248 } 249 return (csw); 250 } 251 252 void 253 dev_relthread(struct cdev *dev, int ref) 254 { 255 256 mtx_assert(&devmtx, MA_NOTOWNED); 257 if (!ref) 258 return; 259 KASSERT(dev->si_threadcount > 0, 260 ("%s threadcount is wrong", dev->si_name)); 261 atomic_subtract_rel_long(&dev->si_threadcount, 1); 262 } 263 264 int 265 nullop(void) 266 { 267 268 return (0); 269 } 270 271 int 272 eopnotsupp(void) 273 { 274 275 return (EOPNOTSUPP); 276 } 277 278 static int 279 enxio(void) 280 { 281 return (ENXIO); 282 } 283 284 static int 285 enodev(void) 286 { 287 return (ENODEV); 288 } 289 290 /* Define a dead_cdevsw for use when devices leave unexpectedly. */ 291 292 #define dead_open (d_open_t *)enxio 293 #define dead_close (d_close_t *)enxio 294 #define dead_read (d_read_t *)enxio 295 #define dead_write (d_write_t *)enxio 296 #define dead_ioctl (d_ioctl_t *)enxio 297 #define dead_poll (d_poll_t *)enodev 298 #define dead_mmap (d_mmap_t *)enodev 299 300 static void 301 dead_strategy(struct bio *bp) 302 { 303 304 biofinish(bp, NULL, ENXIO); 305 } 306 307 #define dead_dump (dumper_t *)enxio 308 #define dead_kqfilter (d_kqfilter_t *)enxio 309 #define dead_mmap_single (d_mmap_single_t *)enodev 310 311 static struct cdevsw dead_cdevsw = { 312 .d_version = D_VERSION, 313 .d_open = dead_open, 314 .d_close = dead_close, 315 .d_read = dead_read, 316 .d_write = dead_write, 317 .d_ioctl = dead_ioctl, 318 .d_poll = dead_poll, 319 .d_mmap = dead_mmap, 320 .d_strategy = dead_strategy, 321 .d_name = "dead", 322 .d_dump = dead_dump, 323 .d_kqfilter = dead_kqfilter, 324 .d_mmap_single = dead_mmap_single 325 }; 326 327 /* Default methods if driver does not specify method */ 328 329 #define null_open (d_open_t *)nullop 330 #define null_close (d_close_t *)nullop 331 #define no_read (d_read_t *)enodev 332 #define no_write (d_write_t *)enodev 333 #define no_ioctl (d_ioctl_t *)enodev 334 #define no_mmap (d_mmap_t *)enodev 335 #define no_kqfilter (d_kqfilter_t *)enodev 336 #define no_mmap_single (d_mmap_single_t *)enodev 337 338 static void 339 no_strategy(struct bio *bp) 340 { 341 342 biofinish(bp, NULL, ENODEV); 343 } 344 345 static int 346 no_poll(struct cdev *dev __unused, int events, struct thread *td __unused) 347 { 348 349 return (poll_no_poll(events)); 350 } 351 352 #define no_dump (dumper_t *)enodev 353 354 static int 355 giant_open(struct cdev *dev, int oflags, int devtype, struct thread *td) 356 { 357 struct cdevsw *dsw; 358 int ref, retval; 359 360 dsw = dev_refthread(dev, &ref); 361 if (dsw == NULL) 362 return (ENXIO); 363 mtx_lock(&Giant); 364 retval = dsw->d_gianttrick->d_open(dev, oflags, devtype, td); 365 mtx_unlock(&Giant); 366 dev_relthread(dev, ref); 367 return (retval); 368 } 369 370 static int 371 giant_fdopen(struct cdev *dev, int oflags, struct thread *td, struct file *fp) 372 { 373 struct cdevsw *dsw; 374 int ref, retval; 375 376 dsw = dev_refthread(dev, &ref); 377 if (dsw == NULL) 378 return (ENXIO); 379 mtx_lock(&Giant); 380 retval = dsw->d_gianttrick->d_fdopen(dev, oflags, td, fp); 381 mtx_unlock(&Giant); 382 dev_relthread(dev, ref); 383 return (retval); 384 } 385 386 static int 387 giant_close(struct cdev *dev, int fflag, int devtype, struct thread *td) 388 { 389 struct cdevsw *dsw; 390 int ref, retval; 391 392 dsw = dev_refthread(dev, &ref); 393 if (dsw == NULL) 394 return (ENXIO); 395 mtx_lock(&Giant); 396 retval = dsw->d_gianttrick->d_close(dev, fflag, devtype, td); 397 mtx_unlock(&Giant); 398 dev_relthread(dev, ref); 399 return (retval); 400 } 401 402 static void 403 giant_strategy(struct bio *bp) 404 { 405 struct cdevsw *dsw; 406 struct cdev *dev; 407 int ref; 408 409 dev = bp->bio_dev; 410 dsw = dev_refthread(dev, &ref); 411 if (dsw == NULL) { 412 biofinish(bp, NULL, ENXIO); 413 return; 414 } 415 mtx_lock(&Giant); 416 dsw->d_gianttrick->d_strategy(bp); 417 mtx_unlock(&Giant); 418 dev_relthread(dev, ref); 419 } 420 421 static int 422 giant_ioctl(struct cdev *dev, u_long cmd, caddr_t data, int fflag, struct thread *td) 423 { 424 struct cdevsw *dsw; 425 int ref, retval; 426 427 dsw = dev_refthread(dev, &ref); 428 if (dsw == NULL) 429 return (ENXIO); 430 mtx_lock(&Giant); 431 retval = dsw->d_gianttrick->d_ioctl(dev, cmd, data, fflag, td); 432 mtx_unlock(&Giant); 433 dev_relthread(dev, ref); 434 return (retval); 435 } 436 437 static int 438 giant_read(struct cdev *dev, struct uio *uio, int ioflag) 439 { 440 struct cdevsw *dsw; 441 int ref, retval; 442 443 dsw = dev_refthread(dev, &ref); 444 if (dsw == NULL) 445 return (ENXIO); 446 mtx_lock(&Giant); 447 retval = dsw->d_gianttrick->d_read(dev, uio, ioflag); 448 mtx_unlock(&Giant); 449 dev_relthread(dev, ref); 450 return (retval); 451 } 452 453 static int 454 giant_write(struct cdev *dev, struct uio *uio, int ioflag) 455 { 456 struct cdevsw *dsw; 457 int ref, retval; 458 459 dsw = dev_refthread(dev, &ref); 460 if (dsw == NULL) 461 return (ENXIO); 462 mtx_lock(&Giant); 463 retval = dsw->d_gianttrick->d_write(dev, uio, ioflag); 464 mtx_unlock(&Giant); 465 dev_relthread(dev, ref); 466 return (retval); 467 } 468 469 static int 470 giant_poll(struct cdev *dev, int events, struct thread *td) 471 { 472 struct cdevsw *dsw; 473 int ref, retval; 474 475 dsw = dev_refthread(dev, &ref); 476 if (dsw == NULL) 477 return (ENXIO); 478 mtx_lock(&Giant); 479 retval = dsw->d_gianttrick->d_poll(dev, events, td); 480 mtx_unlock(&Giant); 481 dev_relthread(dev, ref); 482 return (retval); 483 } 484 485 static int 486 giant_kqfilter(struct cdev *dev, struct knote *kn) 487 { 488 struct cdevsw *dsw; 489 int ref, retval; 490 491 dsw = dev_refthread(dev, &ref); 492 if (dsw == NULL) 493 return (ENXIO); 494 mtx_lock(&Giant); 495 retval = dsw->d_gianttrick->d_kqfilter(dev, kn); 496 mtx_unlock(&Giant); 497 dev_relthread(dev, ref); 498 return (retval); 499 } 500 501 static int 502 giant_mmap(struct cdev *dev, vm_ooffset_t offset, vm_paddr_t *paddr, int nprot, 503 vm_memattr_t *memattr) 504 { 505 struct cdevsw *dsw; 506 int ref, retval; 507 508 dsw = dev_refthread(dev, &ref); 509 if (dsw == NULL) 510 return (ENXIO); 511 mtx_lock(&Giant); 512 retval = dsw->d_gianttrick->d_mmap(dev, offset, paddr, nprot, 513 memattr); 514 mtx_unlock(&Giant); 515 dev_relthread(dev, ref); 516 return (retval); 517 } 518 519 static int 520 giant_mmap_single(struct cdev *dev, vm_ooffset_t *offset, vm_size_t size, 521 vm_object_t *object, int nprot) 522 { 523 struct cdevsw *dsw; 524 int ref, retval; 525 526 dsw = dev_refthread(dev, &ref); 527 if (dsw == NULL) 528 return (ENXIO); 529 mtx_lock(&Giant); 530 retval = dsw->d_gianttrick->d_mmap_single(dev, offset, size, object, 531 nprot); 532 mtx_unlock(&Giant); 533 dev_relthread(dev, ref); 534 return (retval); 535 } 536 537 static void 538 notify(struct cdev *dev, const char *ev, int flags) 539 { 540 static const char prefix[] = "cdev="; 541 char *data; 542 int namelen, mflags; 543 544 if (cold) 545 return; 546 mflags = (flags & MAKEDEV_NOWAIT) ? M_NOWAIT : M_WAITOK; 547 namelen = strlen(dev->si_name); 548 data = malloc(namelen + sizeof(prefix), M_TEMP, mflags); 549 if (data == NULL) 550 return; 551 memcpy(data, prefix, sizeof(prefix) - 1); 552 memcpy(data + sizeof(prefix) - 1, dev->si_name, namelen + 1); 553 devctl_notify_f("DEVFS", "CDEV", ev, data, mflags); 554 free(data, M_TEMP); 555 } 556 557 static void 558 notify_create(struct cdev *dev, int flags) 559 { 560 561 notify(dev, "CREATE", flags); 562 } 563 564 static void 565 notify_destroy(struct cdev *dev) 566 { 567 568 notify(dev, "DESTROY", MAKEDEV_WAITOK); 569 } 570 571 static struct cdev * 572 newdev(struct make_dev_args *args, struct cdev *si) 573 { 574 struct cdev *si2; 575 struct cdevsw *csw; 576 577 mtx_assert(&devmtx, MA_OWNED); 578 csw = args->mda_devsw; 579 if (csw->d_flags & D_NEEDMINOR) { 580 /* We may want to return an existing device */ 581 LIST_FOREACH(si2, &csw->d_devs, si_list) { 582 if (dev2unit(si2) == args->mda_unit) { 583 dev_free_devlocked(si); 584 return (si2); 585 } 586 } 587 } 588 si->si_drv0 = args->mda_unit; 589 si->si_devsw = csw; 590 si->si_drv1 = args->mda_si_drv1; 591 si->si_drv2 = args->mda_si_drv2; 592 LIST_INSERT_HEAD(&csw->d_devs, si, si_list); 593 return (si); 594 } 595 596 static void 597 fini_cdevsw(struct cdevsw *devsw) 598 { 599 struct cdevsw *gt; 600 601 if (devsw->d_gianttrick != NULL) { 602 gt = devsw->d_gianttrick; 603 memcpy(devsw, gt, sizeof *devsw); 604 cdevsw_free_devlocked(gt); 605 devsw->d_gianttrick = NULL; 606 } 607 devsw->d_flags &= ~D_INIT; 608 } 609 610 static int 611 prep_cdevsw(struct cdevsw *devsw, int flags) 612 { 613 struct cdevsw *dsw2; 614 615 mtx_assert(&devmtx, MA_OWNED); 616 if (devsw->d_flags & D_INIT) 617 return (0); 618 if (devsw->d_flags & D_NEEDGIANT) { 619 dev_unlock(); 620 dsw2 = malloc(sizeof *dsw2, M_DEVT, 621 (flags & MAKEDEV_NOWAIT) ? M_NOWAIT : M_WAITOK); 622 dev_lock(); 623 if (dsw2 == NULL && !(devsw->d_flags & D_INIT)) 624 return (ENOMEM); 625 } else 626 dsw2 = NULL; 627 if (devsw->d_flags & D_INIT) { 628 if (dsw2 != NULL) 629 cdevsw_free_devlocked(dsw2); 630 return (0); 631 } 632 633 if (devsw->d_version != D_VERSION_04) { 634 printf( 635 "WARNING: Device driver \"%s\" has wrong version %s\n", 636 devsw->d_name == NULL ? "???" : devsw->d_name, 637 "and is disabled. Recompile KLD module."); 638 devsw->d_open = dead_open; 639 devsw->d_close = dead_close; 640 devsw->d_read = dead_read; 641 devsw->d_write = dead_write; 642 devsw->d_ioctl = dead_ioctl; 643 devsw->d_poll = dead_poll; 644 devsw->d_mmap = dead_mmap; 645 devsw->d_mmap_single = dead_mmap_single; 646 devsw->d_strategy = dead_strategy; 647 devsw->d_dump = dead_dump; 648 devsw->d_kqfilter = dead_kqfilter; 649 } 650 651 if (devsw->d_flags & D_NEEDGIANT) { 652 if (devsw->d_gianttrick == NULL) { 653 memcpy(dsw2, devsw, sizeof *dsw2); 654 devsw->d_gianttrick = dsw2; 655 dsw2 = NULL; 656 } 657 } 658 659 #define FIXUP(member, noop, giant) \ 660 do { \ 661 if (devsw->member == NULL) { \ 662 devsw->member = noop; \ 663 } else if (devsw->d_flags & D_NEEDGIANT) \ 664 devsw->member = giant; \ 665 } \ 666 while (0) 667 668 FIXUP(d_open, null_open, giant_open); 669 FIXUP(d_fdopen, NULL, giant_fdopen); 670 FIXUP(d_close, null_close, giant_close); 671 FIXUP(d_read, no_read, giant_read); 672 FIXUP(d_write, no_write, giant_write); 673 FIXUP(d_ioctl, no_ioctl, giant_ioctl); 674 FIXUP(d_poll, no_poll, giant_poll); 675 FIXUP(d_mmap, no_mmap, giant_mmap); 676 FIXUP(d_strategy, no_strategy, giant_strategy); 677 FIXUP(d_kqfilter, no_kqfilter, giant_kqfilter); 678 FIXUP(d_mmap_single, no_mmap_single, giant_mmap_single); 679 680 if (devsw->d_dump == NULL) devsw->d_dump = no_dump; 681 682 LIST_INIT(&devsw->d_devs); 683 684 devsw->d_flags |= D_INIT; 685 686 if (dsw2 != NULL) 687 cdevsw_free_devlocked(dsw2); 688 return (0); 689 } 690 691 static int 692 prep_devname(struct cdev *dev, const char *fmt, va_list ap) 693 { 694 int len; 695 char *from, *q, *s, *to; 696 697 mtx_assert(&devmtx, MA_OWNED); 698 699 len = vsnrprintf(dev->si_name, sizeof(dev->si_name), 32, fmt, ap); 700 if (len > sizeof(dev->si_name) - 1) 701 return (ENAMETOOLONG); 702 703 /* Strip leading slashes. */ 704 for (from = dev->si_name; *from == '/'; from++) 705 ; 706 707 for (to = dev->si_name; *from != '\0'; from++, to++) { 708 /* 709 * Spaces and double quotation marks cause 710 * problems for the devctl(4) protocol. 711 * Reject names containing those characters. 712 */ 713 if (isspace(*from) || *from == '"') 714 return (EINVAL); 715 /* Treat multiple sequential slashes as single. */ 716 while (from[0] == '/' && from[1] == '/') 717 from++; 718 /* Trailing slash is considered invalid. */ 719 if (from[0] == '/' && from[1] == '\0') 720 return (EINVAL); 721 *to = *from; 722 } 723 *to = '\0'; 724 725 if (dev->si_name[0] == '\0') 726 return (EINVAL); 727 728 /* Disallow "." and ".." components. */ 729 for (s = dev->si_name;;) { 730 for (q = s; *q != '/' && *q != '\0'; q++) 731 ; 732 if (q - s == 1 && s[0] == '.') 733 return (EINVAL); 734 if (q - s == 2 && s[0] == '.' && s[1] == '.') 735 return (EINVAL); 736 if (*q != '/') 737 break; 738 s = q + 1; 739 } 740 741 if (devfs_dev_exists(dev->si_name) != 0) 742 return (EEXIST); 743 744 return (0); 745 } 746 747 void 748 make_dev_args_init_impl(struct make_dev_args *args, size_t sz) 749 { 750 751 bzero(args, sz); 752 args->mda_size = sz; 753 } 754 755 static int 756 make_dev_sv(struct make_dev_args *args1, struct cdev **dres, 757 const char *fmt, va_list ap) 758 { 759 struct cdev *dev, *dev_new; 760 struct make_dev_args args; 761 int res; 762 763 bzero(&args, sizeof(args)); 764 if (sizeof(args) < args1->mda_size) 765 return (EINVAL); 766 bcopy(args1, &args, args1->mda_size); 767 KASSERT((args.mda_flags & MAKEDEV_WAITOK) == 0 || 768 (args.mda_flags & MAKEDEV_NOWAIT) == 0, 769 ("make_dev_sv: both WAITOK and NOWAIT specified")); 770 dev_new = devfs_alloc(args.mda_flags); 771 if (dev_new == NULL) 772 return (ENOMEM); 773 dev_lock(); 774 res = prep_cdevsw(args.mda_devsw, args.mda_flags); 775 if (res != 0) { 776 dev_unlock(); 777 devfs_free(dev_new); 778 return (res); 779 } 780 dev = newdev(&args, dev_new); 781 if ((dev->si_flags & SI_NAMED) == 0) { 782 res = prep_devname(dev, fmt, ap); 783 if (res != 0) { 784 if ((args.mda_flags & MAKEDEV_CHECKNAME) == 0) { 785 panic( 786 "make_dev_sv: bad si_name (error=%d, si_name=%s)", 787 res, dev->si_name); 788 } 789 if (dev == dev_new) { 790 LIST_REMOVE(dev, si_list); 791 dev_unlock(); 792 devfs_free(dev); 793 } else 794 dev_unlock(); 795 return (res); 796 } 797 } 798 if ((args.mda_flags & MAKEDEV_REF) != 0) 799 dev_refl(dev); 800 if ((args.mda_flags & MAKEDEV_ETERNAL) != 0) 801 dev->si_flags |= SI_ETERNAL; 802 if (dev->si_flags & SI_CHEAPCLONE && 803 dev->si_flags & SI_NAMED) { 804 /* 805 * This is allowed as it removes races and generally 806 * simplifies cloning devices. 807 * XXX: still ?? 808 */ 809 dev_unlock_and_free(); 810 *dres = dev; 811 return (0); 812 } 813 KASSERT(!(dev->si_flags & SI_NAMED), 814 ("make_dev() by driver %s on pre-existing device (min=%x, name=%s)", 815 args.mda_devsw->d_name, dev2unit(dev), devtoname(dev))); 816 dev->si_flags |= SI_NAMED; 817 if (args.mda_cr != NULL) 818 dev->si_cred = crhold(args.mda_cr); 819 dev->si_uid = args.mda_uid; 820 dev->si_gid = args.mda_gid; 821 dev->si_mode = args.mda_mode; 822 823 devfs_create(dev); 824 clean_unrhdrl(devfs_inos); 825 dev_unlock_and_free(); 826 827 notify_create(dev, args.mda_flags); 828 829 *dres = dev; 830 return (0); 831 } 832 833 int 834 make_dev_s(struct make_dev_args *args, struct cdev **dres, 835 const char *fmt, ...) 836 { 837 va_list ap; 838 int res; 839 840 va_start(ap, fmt); 841 res = make_dev_sv(args, dres, fmt, ap); 842 va_end(ap); 843 return (res); 844 } 845 846 static int 847 make_dev_credv(int flags, struct cdev **dres, struct cdevsw *devsw, int unit, 848 struct ucred *cr, uid_t uid, gid_t gid, int mode, const char *fmt, 849 va_list ap) 850 { 851 struct make_dev_args args; 852 853 make_dev_args_init(&args); 854 args.mda_flags = flags; 855 args.mda_devsw = devsw; 856 args.mda_cr = cr; 857 args.mda_uid = uid; 858 args.mda_gid = gid; 859 args.mda_mode = mode; 860 args.mda_unit = unit; 861 return (make_dev_sv(&args, dres, fmt, ap)); 862 } 863 864 struct cdev * 865 make_dev(struct cdevsw *devsw, int unit, uid_t uid, gid_t gid, int mode, 866 const char *fmt, ...) 867 { 868 struct cdev *dev; 869 va_list ap; 870 int res __unused; 871 872 va_start(ap, fmt); 873 res = make_dev_credv(0, &dev, devsw, unit, NULL, uid, gid, mode, fmt, 874 ap); 875 va_end(ap); 876 KASSERT(res == 0 && dev != NULL, 877 ("make_dev: failed make_dev_credv (error=%d)", res)); 878 return (dev); 879 } 880 881 struct cdev * 882 make_dev_cred(struct cdevsw *devsw, int unit, struct ucred *cr, uid_t uid, 883 gid_t gid, int mode, const char *fmt, ...) 884 { 885 struct cdev *dev; 886 va_list ap; 887 int res __unused; 888 889 va_start(ap, fmt); 890 res = make_dev_credv(0, &dev, devsw, unit, cr, uid, gid, mode, fmt, ap); 891 va_end(ap); 892 893 KASSERT(res == 0 && dev != NULL, 894 ("make_dev_cred: failed make_dev_credv (error=%d)", res)); 895 return (dev); 896 } 897 898 struct cdev * 899 make_dev_credf(int flags, struct cdevsw *devsw, int unit, struct ucred *cr, 900 uid_t uid, gid_t gid, int mode, const char *fmt, ...) 901 { 902 struct cdev *dev; 903 va_list ap; 904 int res; 905 906 va_start(ap, fmt); 907 res = make_dev_credv(flags, &dev, devsw, unit, cr, uid, gid, mode, 908 fmt, ap); 909 va_end(ap); 910 911 KASSERT(((flags & MAKEDEV_NOWAIT) != 0 && res == ENOMEM) || 912 ((flags & MAKEDEV_CHECKNAME) != 0 && res != ENOMEM) || res == 0, 913 ("make_dev_credf: failed make_dev_credv (error=%d)", res)); 914 return (res == 0 ? dev : NULL); 915 } 916 917 int 918 make_dev_p(int flags, struct cdev **cdev, struct cdevsw *devsw, 919 struct ucred *cr, uid_t uid, gid_t gid, int mode, const char *fmt, ...) 920 { 921 va_list ap; 922 int res; 923 924 va_start(ap, fmt); 925 res = make_dev_credv(flags, cdev, devsw, 0, cr, uid, gid, mode, 926 fmt, ap); 927 va_end(ap); 928 929 KASSERT(((flags & MAKEDEV_NOWAIT) != 0 && res == ENOMEM) || 930 ((flags & MAKEDEV_CHECKNAME) != 0 && res != ENOMEM) || res == 0, 931 ("make_dev_p: failed make_dev_credv (error=%d)", res)); 932 return (res); 933 } 934 935 static void 936 dev_dependsl(struct cdev *pdev, struct cdev *cdev) 937 { 938 939 cdev->si_parent = pdev; 940 cdev->si_flags |= SI_CHILD; 941 LIST_INSERT_HEAD(&pdev->si_children, cdev, si_siblings); 942 } 943 944 945 void 946 dev_depends(struct cdev *pdev, struct cdev *cdev) 947 { 948 949 dev_lock(); 950 dev_dependsl(pdev, cdev); 951 dev_unlock(); 952 } 953 954 static int 955 make_dev_alias_v(int flags, struct cdev **cdev, struct cdev *pdev, 956 const char *fmt, va_list ap) 957 { 958 struct cdev *dev; 959 int error; 960 961 KASSERT(pdev != NULL, ("make_dev_alias_v: pdev is NULL")); 962 KASSERT((flags & MAKEDEV_WAITOK) == 0 || (flags & MAKEDEV_NOWAIT) == 0, 963 ("make_dev_alias_v: both WAITOK and NOWAIT specified")); 964 KASSERT((flags & ~(MAKEDEV_WAITOK | MAKEDEV_NOWAIT | 965 MAKEDEV_CHECKNAME)) == 0, 966 ("make_dev_alias_v: invalid flags specified (flags=%02x)", flags)); 967 968 dev = devfs_alloc(flags); 969 if (dev == NULL) 970 return (ENOMEM); 971 dev_lock(); 972 dev->si_flags |= SI_ALIAS; 973 error = prep_devname(dev, fmt, ap); 974 if (error != 0) { 975 if ((flags & MAKEDEV_CHECKNAME) == 0) { 976 panic("make_dev_alias_v: bad si_name " 977 "(error=%d, si_name=%s)", error, dev->si_name); 978 } 979 dev_unlock(); 980 devfs_free(dev); 981 return (error); 982 } 983 dev->si_flags |= SI_NAMED; 984 devfs_create(dev); 985 dev_dependsl(pdev, dev); 986 clean_unrhdrl(devfs_inos); 987 dev_unlock(); 988 989 notify_create(dev, flags); 990 *cdev = dev; 991 992 return (0); 993 } 994 995 struct cdev * 996 make_dev_alias(struct cdev *pdev, const char *fmt, ...) 997 { 998 struct cdev *dev; 999 va_list ap; 1000 int res __unused; 1001 1002 va_start(ap, fmt); 1003 res = make_dev_alias_v(MAKEDEV_WAITOK, &dev, pdev, fmt, ap); 1004 va_end(ap); 1005 1006 KASSERT(res == 0 && dev != NULL, 1007 ("make_dev_alias: failed make_dev_alias_v (error=%d)", res)); 1008 return (dev); 1009 } 1010 1011 int 1012 make_dev_alias_p(int flags, struct cdev **cdev, struct cdev *pdev, 1013 const char *fmt, ...) 1014 { 1015 va_list ap; 1016 int res; 1017 1018 va_start(ap, fmt); 1019 res = make_dev_alias_v(flags, cdev, pdev, fmt, ap); 1020 va_end(ap); 1021 return (res); 1022 } 1023 1024 int 1025 make_dev_physpath_alias(int flags, struct cdev **cdev, struct cdev *pdev, 1026 struct cdev *old_alias, const char *physpath) 1027 { 1028 char *devfspath; 1029 int physpath_len; 1030 int max_parentpath_len; 1031 int parentpath_len; 1032 int devfspathbuf_len; 1033 int mflags; 1034 int ret; 1035 1036 *cdev = NULL; 1037 devfspath = NULL; 1038 physpath_len = strlen(physpath); 1039 ret = EINVAL; 1040 if (physpath_len == 0) 1041 goto out; 1042 1043 if (strncmp("id1,", physpath, 4) == 0) { 1044 physpath += 4; 1045 physpath_len -= 4; 1046 if (physpath_len == 0) 1047 goto out; 1048 } 1049 1050 max_parentpath_len = SPECNAMELEN - physpath_len - /*/*/1; 1051 parentpath_len = strlen(pdev->si_name); 1052 if (max_parentpath_len < parentpath_len) { 1053 if (bootverbose) 1054 printf("WARNING: Unable to alias %s " 1055 "to %s/%s - path too long\n", 1056 pdev->si_name, physpath, pdev->si_name); 1057 ret = ENAMETOOLONG; 1058 goto out; 1059 } 1060 1061 mflags = (flags & MAKEDEV_NOWAIT) ? M_NOWAIT : M_WAITOK; 1062 devfspathbuf_len = physpath_len + /*/*/1 + parentpath_len + /*NUL*/1; 1063 devfspath = malloc(devfspathbuf_len, M_DEVBUF, mflags); 1064 if (devfspath == NULL) { 1065 ret = ENOMEM; 1066 goto out; 1067 } 1068 1069 sprintf(devfspath, "%s/%s", physpath, pdev->si_name); 1070 if (old_alias != NULL && strcmp(old_alias->si_name, devfspath) == 0) { 1071 /* Retain the existing alias. */ 1072 *cdev = old_alias; 1073 old_alias = NULL; 1074 ret = 0; 1075 } else { 1076 ret = make_dev_alias_p(flags, cdev, pdev, "%s", devfspath); 1077 } 1078 out: 1079 if (old_alias != NULL) 1080 destroy_dev(old_alias); 1081 if (devfspath != NULL) 1082 free(devfspath, M_DEVBUF); 1083 return (ret); 1084 } 1085 1086 static void 1087 destroy_devl(struct cdev *dev) 1088 { 1089 struct cdevsw *csw; 1090 struct cdev_privdata *p; 1091 struct cdev_priv *cdp; 1092 1093 mtx_assert(&devmtx, MA_OWNED); 1094 KASSERT(dev->si_flags & SI_NAMED, 1095 ("WARNING: Driver mistake: destroy_dev on %d\n", dev2unit(dev))); 1096 KASSERT((dev->si_flags & SI_ETERNAL) == 0, 1097 ("WARNING: Driver mistake: destroy_dev on eternal %d\n", 1098 dev2unit(dev))); 1099 1100 cdp = cdev2priv(dev); 1101 if ((cdp->cdp_flags & CDP_UNREF_DTR) == 0) { 1102 /* 1103 * Avoid race with dev_rel(), e.g. from the populate 1104 * loop. If CDP_UNREF_DTR flag is set, the reference 1105 * to be dropped at the end of destroy_devl() was 1106 * already taken by delist_dev_locked(). 1107 */ 1108 dev_refl(dev); 1109 1110 devfs_destroy(dev); 1111 } 1112 1113 /* Remove name marking */ 1114 dev->si_flags &= ~SI_NAMED; 1115 1116 /* If we are a child, remove us from the parents list */ 1117 if (dev->si_flags & SI_CHILD) { 1118 LIST_REMOVE(dev, si_siblings); 1119 dev->si_flags &= ~SI_CHILD; 1120 } 1121 1122 /* Kill our children */ 1123 while (!LIST_EMPTY(&dev->si_children)) 1124 destroy_devl(LIST_FIRST(&dev->si_children)); 1125 1126 /* Remove from clone list */ 1127 if (dev->si_flags & SI_CLONELIST) { 1128 LIST_REMOVE(dev, si_clone); 1129 dev->si_flags &= ~SI_CLONELIST; 1130 } 1131 1132 csw = dev->si_devsw; 1133 dev->si_devsw = NULL; /* already NULL for SI_ALIAS */ 1134 while (csw != NULL && csw->d_purge != NULL && dev->si_threadcount) { 1135 csw->d_purge(dev); 1136 msleep(csw, &devmtx, PRIBIO, "devprg", hz/10); 1137 if (dev->si_threadcount) 1138 printf("Still %lu threads in %s\n", 1139 dev->si_threadcount, devtoname(dev)); 1140 } 1141 while (dev->si_threadcount != 0) { 1142 /* Use unique dummy wait ident */ 1143 msleep(&csw, &devmtx, PRIBIO, "devdrn", hz / 10); 1144 } 1145 1146 dev_unlock(); 1147 if ((cdp->cdp_flags & CDP_UNREF_DTR) == 0) { 1148 /* avoid out of order notify events */ 1149 notify_destroy(dev); 1150 } 1151 mtx_lock(&cdevpriv_mtx); 1152 while ((p = LIST_FIRST(&cdp->cdp_fdpriv)) != NULL) { 1153 devfs_destroy_cdevpriv(p); 1154 mtx_lock(&cdevpriv_mtx); 1155 } 1156 mtx_unlock(&cdevpriv_mtx); 1157 dev_lock(); 1158 1159 dev->si_drv1 = 0; 1160 dev->si_drv2 = 0; 1161 bzero(&dev->__si_u, sizeof(dev->__si_u)); 1162 1163 if (!(dev->si_flags & SI_ALIAS)) { 1164 /* Remove from cdevsw list */ 1165 LIST_REMOVE(dev, si_list); 1166 1167 /* If cdevsw has no more struct cdev *'s, clean it */ 1168 if (LIST_EMPTY(&csw->d_devs)) { 1169 fini_cdevsw(csw); 1170 wakeup(&csw->d_devs); 1171 } 1172 } 1173 dev->si_flags &= ~SI_ALIAS; 1174 cdp->cdp_flags &= ~CDP_UNREF_DTR; 1175 dev->si_refcount--; 1176 1177 if (dev->si_refcount > 0) 1178 LIST_INSERT_HEAD(&dead_cdevsw.d_devs, dev, si_list); 1179 else 1180 dev_free_devlocked(dev); 1181 } 1182 1183 static void 1184 delist_dev_locked(struct cdev *dev) 1185 { 1186 struct cdev_priv *cdp; 1187 struct cdev *child; 1188 1189 mtx_assert(&devmtx, MA_OWNED); 1190 cdp = cdev2priv(dev); 1191 if ((cdp->cdp_flags & CDP_UNREF_DTR) != 0) 1192 return; 1193 cdp->cdp_flags |= CDP_UNREF_DTR; 1194 dev_refl(dev); 1195 devfs_destroy(dev); 1196 LIST_FOREACH(child, &dev->si_children, si_siblings) 1197 delist_dev_locked(child); 1198 dev_unlock(); 1199 /* ensure the destroy event is queued in order */ 1200 notify_destroy(dev); 1201 dev_lock(); 1202 } 1203 1204 /* 1205 * This function will delist a character device and its children from 1206 * the directory listing and create a destroy event without waiting 1207 * for all character device references to go away. At some later point 1208 * destroy_dev() must be called to complete the character device 1209 * destruction. After calling this function the character device name 1210 * can instantly be re-used. 1211 */ 1212 void 1213 delist_dev(struct cdev *dev) 1214 { 1215 1216 WITNESS_WARN(WARN_GIANTOK | WARN_SLEEPOK, NULL, "delist_dev"); 1217 dev_lock(); 1218 delist_dev_locked(dev); 1219 dev_unlock(); 1220 } 1221 1222 void 1223 destroy_dev(struct cdev *dev) 1224 { 1225 1226 WITNESS_WARN(WARN_GIANTOK | WARN_SLEEPOK, NULL, "destroy_dev"); 1227 dev_lock(); 1228 destroy_devl(dev); 1229 dev_unlock_and_free(); 1230 } 1231 1232 const char * 1233 devtoname(struct cdev *dev) 1234 { 1235 1236 return (dev->si_name); 1237 } 1238 1239 int 1240 dev_stdclone(char *name, char **namep, const char *stem, int *unit) 1241 { 1242 int u, i; 1243 1244 i = strlen(stem); 1245 if (bcmp(stem, name, i) != 0) 1246 return (0); 1247 if (!isdigit(name[i])) 1248 return (0); 1249 u = 0; 1250 if (name[i] == '0' && isdigit(name[i+1])) 1251 return (0); 1252 while (isdigit(name[i])) { 1253 u *= 10; 1254 u += name[i++] - '0'; 1255 } 1256 if (u > 0xffffff) 1257 return (0); 1258 *unit = u; 1259 if (namep) 1260 *namep = &name[i]; 1261 if (name[i]) 1262 return (2); 1263 return (1); 1264 } 1265 1266 /* 1267 * Helper functions for cloning device drivers. 1268 * 1269 * The objective here is to make it unnecessary for the device drivers to 1270 * use rman or similar to manage their unit number space. Due to the way 1271 * we do "on-demand" devices, using rman or other "private" methods 1272 * will be very tricky to lock down properly once we lock down this file. 1273 * 1274 * Instead we give the drivers these routines which puts the struct cdev *'s 1275 * that are to be managed on their own list, and gives the driver the ability 1276 * to ask for the first free unit number or a given specified unit number. 1277 * 1278 * In addition these routines support paired devices (pty, nmdm and similar) 1279 * by respecting a number of "flag" bits in the minor number. 1280 * 1281 */ 1282 1283 struct clonedevs { 1284 LIST_HEAD(,cdev) head; 1285 }; 1286 1287 void 1288 clone_setup(struct clonedevs **cdp) 1289 { 1290 1291 *cdp = malloc(sizeof **cdp, M_DEVBUF, M_WAITOK | M_ZERO); 1292 LIST_INIT(&(*cdp)->head); 1293 } 1294 1295 int 1296 clone_create(struct clonedevs **cdp, struct cdevsw *csw, int *up, 1297 struct cdev **dp, int extra) 1298 { 1299 struct clonedevs *cd; 1300 struct cdev *dev, *ndev, *dl, *de; 1301 struct make_dev_args args; 1302 int unit, low, u; 1303 1304 KASSERT(*cdp != NULL, 1305 ("clone_setup() not called in driver \"%s\"", csw->d_name)); 1306 KASSERT(!(extra & CLONE_UNITMASK), 1307 ("Illegal extra bits (0x%x) in clone_create", extra)); 1308 KASSERT(*up <= CLONE_UNITMASK, 1309 ("Too high unit (0x%x) in clone_create", *up)); 1310 KASSERT(csw->d_flags & D_NEEDMINOR, 1311 ("clone_create() on cdevsw without minor numbers")); 1312 1313 1314 /* 1315 * Search the list for a lot of things in one go: 1316 * A preexisting match is returned immediately. 1317 * The lowest free unit number if we are passed -1, and the place 1318 * in the list where we should insert that new element. 1319 * The place to insert a specified unit number, if applicable 1320 * the end of the list. 1321 */ 1322 unit = *up; 1323 ndev = devfs_alloc(MAKEDEV_WAITOK); 1324 dev_lock(); 1325 prep_cdevsw(csw, MAKEDEV_WAITOK); 1326 low = extra; 1327 de = dl = NULL; 1328 cd = *cdp; 1329 LIST_FOREACH(dev, &cd->head, si_clone) { 1330 KASSERT(dev->si_flags & SI_CLONELIST, 1331 ("Dev %p(%s) should be on clonelist", dev, dev->si_name)); 1332 u = dev2unit(dev); 1333 if (u == (unit | extra)) { 1334 *dp = dev; 1335 dev_unlock(); 1336 devfs_free(ndev); 1337 return (0); 1338 } 1339 if (unit == -1 && u == low) { 1340 low++; 1341 de = dev; 1342 continue; 1343 } else if (u < (unit | extra)) { 1344 de = dev; 1345 continue; 1346 } else if (u > (unit | extra)) { 1347 dl = dev; 1348 break; 1349 } 1350 } 1351 if (unit == -1) 1352 unit = low & CLONE_UNITMASK; 1353 make_dev_args_init(&args); 1354 args.mda_unit = unit | extra; 1355 args.mda_devsw = csw; 1356 dev = newdev(&args, ndev); 1357 if (dev->si_flags & SI_CLONELIST) { 1358 printf("dev %p (%s) is on clonelist\n", dev, dev->si_name); 1359 printf("unit=%d, low=%d, extra=0x%x\n", unit, low, extra); 1360 LIST_FOREACH(dev, &cd->head, si_clone) { 1361 printf("\t%p %s\n", dev, dev->si_name); 1362 } 1363 panic("foo"); 1364 } 1365 KASSERT(!(dev->si_flags & SI_CLONELIST), 1366 ("Dev %p(%s) should not be on clonelist", dev, dev->si_name)); 1367 if (dl != NULL) 1368 LIST_INSERT_BEFORE(dl, dev, si_clone); 1369 else if (de != NULL) 1370 LIST_INSERT_AFTER(de, dev, si_clone); 1371 else 1372 LIST_INSERT_HEAD(&cd->head, dev, si_clone); 1373 dev->si_flags |= SI_CLONELIST; 1374 *up = unit; 1375 dev_unlock_and_free(); 1376 return (1); 1377 } 1378 1379 /* 1380 * Kill everything still on the list. The driver should already have 1381 * disposed of any softc hung of the struct cdev *'s at this time. 1382 */ 1383 void 1384 clone_cleanup(struct clonedevs **cdp) 1385 { 1386 struct cdev *dev; 1387 struct cdev_priv *cp; 1388 struct clonedevs *cd; 1389 1390 cd = *cdp; 1391 if (cd == NULL) 1392 return; 1393 dev_lock(); 1394 while (!LIST_EMPTY(&cd->head)) { 1395 dev = LIST_FIRST(&cd->head); 1396 LIST_REMOVE(dev, si_clone); 1397 KASSERT(dev->si_flags & SI_CLONELIST, 1398 ("Dev %p(%s) should be on clonelist", dev, dev->si_name)); 1399 dev->si_flags &= ~SI_CLONELIST; 1400 cp = cdev2priv(dev); 1401 if (!(cp->cdp_flags & CDP_SCHED_DTR)) { 1402 cp->cdp_flags |= CDP_SCHED_DTR; 1403 KASSERT(dev->si_flags & SI_NAMED, 1404 ("Driver has goofed in cloning underways udev %jx unit %x", 1405 (uintmax_t)dev2udev(dev), dev2unit(dev))); 1406 destroy_devl(dev); 1407 } 1408 } 1409 dev_unlock_and_free(); 1410 free(cd, M_DEVBUF); 1411 *cdp = NULL; 1412 } 1413 1414 static TAILQ_HEAD(, cdev_priv) dev_ddtr = 1415 TAILQ_HEAD_INITIALIZER(dev_ddtr); 1416 static struct task dev_dtr_task = TASK_INITIALIZER(0, destroy_dev_tq, NULL); 1417 1418 static void 1419 destroy_dev_tq(void *ctx, int pending) 1420 { 1421 struct cdev_priv *cp; 1422 struct cdev *dev; 1423 void (*cb)(void *); 1424 void *cb_arg; 1425 1426 dev_lock(); 1427 while (!TAILQ_EMPTY(&dev_ddtr)) { 1428 cp = TAILQ_FIRST(&dev_ddtr); 1429 dev = &cp->cdp_c; 1430 KASSERT(cp->cdp_flags & CDP_SCHED_DTR, 1431 ("cdev %p in dev_destroy_tq without CDP_SCHED_DTR", cp)); 1432 TAILQ_REMOVE(&dev_ddtr, cp, cdp_dtr_list); 1433 cb = cp->cdp_dtr_cb; 1434 cb_arg = cp->cdp_dtr_cb_arg; 1435 destroy_devl(dev); 1436 dev_unlock_and_free(); 1437 dev_rel(dev); 1438 if (cb != NULL) 1439 cb(cb_arg); 1440 dev_lock(); 1441 } 1442 dev_unlock(); 1443 } 1444 1445 /* 1446 * devmtx shall be locked on entry. devmtx will be unlocked after 1447 * function return. 1448 */ 1449 static int 1450 destroy_dev_sched_cbl(struct cdev *dev, void (*cb)(void *), void *arg) 1451 { 1452 struct cdev_priv *cp; 1453 1454 mtx_assert(&devmtx, MA_OWNED); 1455 cp = cdev2priv(dev); 1456 if (cp->cdp_flags & CDP_SCHED_DTR) { 1457 dev_unlock(); 1458 return (0); 1459 } 1460 dev_refl(dev); 1461 cp->cdp_flags |= CDP_SCHED_DTR; 1462 cp->cdp_dtr_cb = cb; 1463 cp->cdp_dtr_cb_arg = arg; 1464 TAILQ_INSERT_TAIL(&dev_ddtr, cp, cdp_dtr_list); 1465 dev_unlock(); 1466 taskqueue_enqueue(taskqueue_swi_giant, &dev_dtr_task); 1467 return (1); 1468 } 1469 1470 int 1471 destroy_dev_sched_cb(struct cdev *dev, void (*cb)(void *), void *arg) 1472 { 1473 1474 dev_lock(); 1475 return (destroy_dev_sched_cbl(dev, cb, arg)); 1476 } 1477 1478 int 1479 destroy_dev_sched(struct cdev *dev) 1480 { 1481 1482 return (destroy_dev_sched_cb(dev, NULL, NULL)); 1483 } 1484 1485 void 1486 destroy_dev_drain(struct cdevsw *csw) 1487 { 1488 1489 dev_lock(); 1490 while (!LIST_EMPTY(&csw->d_devs)) { 1491 msleep(&csw->d_devs, &devmtx, PRIBIO, "devscd", hz/10); 1492 } 1493 dev_unlock(); 1494 } 1495 1496 void 1497 drain_dev_clone_events(void) 1498 { 1499 1500 sx_xlock(&clone_drain_lock); 1501 sx_xunlock(&clone_drain_lock); 1502 } 1503 1504 #include "opt_ddb.h" 1505 #ifdef DDB 1506 #include <sys/kernel.h> 1507 1508 #include <ddb/ddb.h> 1509 1510 DB_SHOW_COMMAND(cdev, db_show_cdev) 1511 { 1512 struct cdev_priv *cdp; 1513 struct cdev *dev; 1514 u_int flags; 1515 char buf[512]; 1516 1517 if (!have_addr) { 1518 TAILQ_FOREACH(cdp, &cdevp_list, cdp_list) { 1519 dev = &cdp->cdp_c; 1520 db_printf("%s %p\n", dev->si_name, dev); 1521 if (db_pager_quit) 1522 break; 1523 } 1524 return; 1525 } 1526 1527 dev = (struct cdev *)addr; 1528 cdp = cdev2priv(dev); 1529 db_printf("dev %s ref %d use %ld thr %ld inuse %u fdpriv %p\n", 1530 dev->si_name, dev->si_refcount, dev->si_usecount, 1531 dev->si_threadcount, cdp->cdp_inuse, cdp->cdp_fdpriv.lh_first); 1532 db_printf("devsw %p si_drv0 %d si_drv1 %p si_drv2 %p\n", 1533 dev->si_devsw, dev->si_drv0, dev->si_drv1, dev->si_drv2); 1534 flags = dev->si_flags; 1535 #define SI_FLAG(flag) do { \ 1536 if (flags & (flag)) { \ 1537 if (buf[0] != '\0') \ 1538 strlcat(buf, ", ", sizeof(buf)); \ 1539 strlcat(buf, (#flag) + 3, sizeof(buf)); \ 1540 flags &= ~(flag); \ 1541 } \ 1542 } while (0) 1543 buf[0] = '\0'; 1544 SI_FLAG(SI_ETERNAL); 1545 SI_FLAG(SI_ALIAS); 1546 SI_FLAG(SI_NAMED); 1547 SI_FLAG(SI_CHEAPCLONE); 1548 SI_FLAG(SI_CHILD); 1549 SI_FLAG(SI_DUMPDEV); 1550 SI_FLAG(SI_CLONELIST); 1551 db_printf("si_flags %s\n", buf); 1552 1553 flags = cdp->cdp_flags; 1554 #define CDP_FLAG(flag) do { \ 1555 if (flags & (flag)) { \ 1556 if (buf[0] != '\0') \ 1557 strlcat(buf, ", ", sizeof(buf)); \ 1558 strlcat(buf, (#flag) + 4, sizeof(buf)); \ 1559 flags &= ~(flag); \ 1560 } \ 1561 } while (0) 1562 buf[0] = '\0'; 1563 CDP_FLAG(CDP_ACTIVE); 1564 CDP_FLAG(CDP_SCHED_DTR); 1565 db_printf("cdp_flags %s\n", buf); 1566 } 1567 #endif 1568