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/bio.h> 36 #include <sys/devctl.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 void destroy_dev_tq_giant(void *ctx, int pending); 62 static int make_dev_credv(int flags, struct cdev **dres, struct cdevsw *devsw, 63 int unit, struct ucred *cr, uid_t uid, gid_t gid, int mode, const char *fmt, 64 va_list ap); 65 66 static struct cdev_priv_list cdevp_free_list = 67 TAILQ_HEAD_INITIALIZER(cdevp_free_list); 68 static SLIST_HEAD(free_cdevsw, cdevsw) cdevsw_gt_post_list = 69 SLIST_HEAD_INITIALIZER(cdevsw_gt_post_list); 70 71 void 72 dev_lock(void) 73 { 74 75 mtx_lock(&devmtx); 76 } 77 78 /* 79 * Free all the memory collected while the cdev mutex was 80 * locked. Since devmtx is after the system map mutex, free() cannot 81 * be called immediately and is postponed until cdev mutex can be 82 * dropped. 83 */ 84 static void 85 dev_unlock_and_free(void) 86 { 87 struct cdev_priv_list cdp_free; 88 struct free_cdevsw csw_free; 89 struct cdev_priv *cdp; 90 struct cdevsw *csw; 91 92 dev_lock_assert_locked(); 93 94 /* 95 * Make the local copy of the list heads while the dev_mtx is 96 * held. Free it later. 97 */ 98 TAILQ_INIT(&cdp_free); 99 TAILQ_CONCAT(&cdp_free, &cdevp_free_list, cdp_list); 100 csw_free = cdevsw_gt_post_list; 101 SLIST_INIT(&cdevsw_gt_post_list); 102 103 mtx_unlock(&devmtx); 104 105 while ((cdp = TAILQ_FIRST(&cdp_free)) != NULL) { 106 TAILQ_REMOVE(&cdp_free, cdp, cdp_list); 107 devfs_free(&cdp->cdp_c); 108 } 109 while ((csw = SLIST_FIRST(&csw_free)) != NULL) { 110 SLIST_REMOVE_HEAD(&csw_free, d_postfree_list); 111 free(csw, M_DEVT); 112 } 113 } 114 115 static void 116 dev_free_devlocked(struct cdev *cdev) 117 { 118 struct cdev_priv *cdp; 119 120 dev_lock_assert_locked(); 121 cdp = cdev2priv(cdev); 122 KASSERT((cdp->cdp_flags & CDP_UNREF_DTR) == 0, 123 ("destroy_dev() was not called after delist_dev(%p)", cdev)); 124 TAILQ_INSERT_HEAD(&cdevp_free_list, cdp, cdp_list); 125 } 126 127 static void 128 cdevsw_free_devlocked(struct cdevsw *csw) 129 { 130 131 dev_lock_assert_locked(); 132 SLIST_INSERT_HEAD(&cdevsw_gt_post_list, csw, d_postfree_list); 133 } 134 135 void 136 dev_unlock(void) 137 { 138 139 mtx_unlock(&devmtx); 140 } 141 142 void 143 dev_ref(struct cdev *dev) 144 { 145 146 dev_lock_assert_unlocked(); 147 mtx_lock(&devmtx); 148 dev->si_refcount++; 149 mtx_unlock(&devmtx); 150 } 151 152 void 153 dev_refl(struct cdev *dev) 154 { 155 156 dev_lock_assert_locked(); 157 dev->si_refcount++; 158 } 159 160 void 161 dev_rel(struct cdev *dev) 162 { 163 int flag = 0; 164 165 dev_lock_assert_unlocked(); 166 dev_lock(); 167 dev->si_refcount--; 168 KASSERT(dev->si_refcount >= 0, 169 ("dev_rel(%s) gave negative count", devtoname(dev))); 170 if (dev->si_devsw == NULL && dev->si_refcount == 0) { 171 LIST_REMOVE(dev, si_list); 172 flag = 1; 173 } 174 dev_unlock(); 175 if (flag) 176 devfs_free(dev); 177 } 178 179 struct cdevsw * 180 dev_refthread(struct cdev *dev, int *ref) 181 { 182 struct cdevsw *csw; 183 struct cdev_priv *cdp; 184 185 dev_lock_assert_unlocked(); 186 if ((dev->si_flags & SI_ETERNAL) != 0) { 187 *ref = 0; 188 return (dev->si_devsw); 189 } 190 cdp = cdev2priv(dev); 191 mtx_lock(&cdp->cdp_threadlock); 192 csw = dev->si_devsw; 193 if (csw != NULL) { 194 if ((cdp->cdp_flags & CDP_SCHED_DTR) == 0) 195 atomic_add_long(&dev->si_threadcount, 1); 196 else 197 csw = NULL; 198 } 199 mtx_unlock(&cdp->cdp_threadlock); 200 if (csw != NULL) 201 *ref = 1; 202 return (csw); 203 } 204 205 struct cdevsw * 206 devvn_refthread(struct vnode *vp, struct cdev **devp, int *ref) 207 { 208 struct cdevsw *csw; 209 struct cdev_priv *cdp; 210 struct cdev *dev; 211 212 dev_lock_assert_unlocked(); 213 if ((vp->v_vflag & VV_ETERNALDEV) != 0) { 214 dev = vp->v_rdev; 215 if (dev == NULL) 216 return (NULL); 217 KASSERT((dev->si_flags & SI_ETERNAL) != 0, 218 ("Not eternal cdev")); 219 *ref = 0; 220 csw = dev->si_devsw; 221 KASSERT(csw != NULL, ("Eternal cdev is destroyed")); 222 *devp = dev; 223 return (csw); 224 } 225 226 csw = NULL; 227 VI_LOCK(vp); 228 dev = vp->v_rdev; 229 if (dev == NULL) { 230 VI_UNLOCK(vp); 231 return (NULL); 232 } 233 cdp = cdev2priv(dev); 234 mtx_lock(&cdp->cdp_threadlock); 235 if ((cdp->cdp_flags & CDP_SCHED_DTR) == 0) { 236 csw = dev->si_devsw; 237 if (csw != NULL) 238 atomic_add_long(&dev->si_threadcount, 1); 239 } 240 mtx_unlock(&cdp->cdp_threadlock); 241 VI_UNLOCK(vp); 242 if (csw != NULL) { 243 *devp = dev; 244 *ref = 1; 245 } 246 return (csw); 247 } 248 249 void 250 dev_relthread(struct cdev *dev, int ref) 251 { 252 253 dev_lock_assert_unlocked(); 254 if (!ref) 255 return; 256 KASSERT(dev->si_threadcount > 0, 257 ("%s threadcount is wrong", dev->si_name)); 258 atomic_subtract_rel_long(&dev->si_threadcount, 1); 259 } 260 261 int 262 nullop(void) 263 { 264 265 return (0); 266 } 267 268 int 269 eopnotsupp(void) 270 { 271 272 return (EOPNOTSUPP); 273 } 274 275 static int 276 enxio(void) 277 { 278 return (ENXIO); 279 } 280 281 static int 282 enodev(void) 283 { 284 return (ENODEV); 285 } 286 287 /* Define a dead_cdevsw for use when devices leave unexpectedly. */ 288 289 #define dead_open (d_open_t *)enxio 290 #define dead_close (d_close_t *)enxio 291 #define dead_read (d_read_t *)enxio 292 #define dead_write (d_write_t *)enxio 293 #define dead_ioctl (d_ioctl_t *)enxio 294 #define dead_poll (d_poll_t *)enodev 295 #define dead_mmap (d_mmap_t *)enodev 296 297 static void 298 dead_strategy(struct bio *bp) 299 { 300 301 biofinish(bp, NULL, ENXIO); 302 } 303 304 #define dead_kqfilter (d_kqfilter_t *)enxio 305 #define dead_mmap_single (d_mmap_single_t *)enodev 306 307 static struct cdevsw dead_cdevsw = { 308 .d_version = D_VERSION, 309 .d_open = dead_open, 310 .d_close = dead_close, 311 .d_read = dead_read, 312 .d_write = dead_write, 313 .d_ioctl = dead_ioctl, 314 .d_poll = dead_poll, 315 .d_mmap = dead_mmap, 316 .d_strategy = dead_strategy, 317 .d_name = "dead", 318 .d_kqfilter = dead_kqfilter, 319 .d_mmap_single = dead_mmap_single 320 }; 321 322 /* Default methods if driver does not specify method */ 323 324 #define null_open (d_open_t *)nullop 325 #define null_close (d_close_t *)nullop 326 #define no_read (d_read_t *)enodev 327 #define no_write (d_write_t *)enodev 328 #define no_ioctl (d_ioctl_t *)enodev 329 #define no_mmap (d_mmap_t *)enodev 330 #define no_kqfilter (d_kqfilter_t *)enodev 331 #define no_mmap_single (d_mmap_single_t *)enodev 332 333 static void 334 no_strategy(struct bio *bp) 335 { 336 337 biofinish(bp, NULL, ENODEV); 338 } 339 340 static int 341 no_poll(struct cdev *dev __unused, int events, struct thread *td __unused) 342 { 343 344 return (poll_no_poll(events)); 345 } 346 347 static int 348 giant_open(struct cdev *dev, int oflags, int devtype, struct thread *td) 349 { 350 struct cdevsw *dsw; 351 int ref, retval; 352 353 dsw = dev_refthread(dev, &ref); 354 if (dsw == NULL) 355 return (ENXIO); 356 mtx_lock(&Giant); 357 retval = dsw->d_gianttrick->d_open(dev, oflags, devtype, td); 358 mtx_unlock(&Giant); 359 dev_relthread(dev, ref); 360 return (retval); 361 } 362 363 static int 364 giant_fdopen(struct cdev *dev, int oflags, struct thread *td, struct file *fp) 365 { 366 struct cdevsw *dsw; 367 int ref, retval; 368 369 dsw = dev_refthread(dev, &ref); 370 if (dsw == NULL) 371 return (ENXIO); 372 mtx_lock(&Giant); 373 retval = dsw->d_gianttrick->d_fdopen(dev, oflags, td, fp); 374 mtx_unlock(&Giant); 375 dev_relthread(dev, ref); 376 return (retval); 377 } 378 379 static int 380 giant_close(struct cdev *dev, int fflag, int devtype, struct thread *td) 381 { 382 struct cdevsw *dsw; 383 int ref, retval; 384 385 dsw = dev_refthread(dev, &ref); 386 if (dsw == NULL) 387 return (ENXIO); 388 mtx_lock(&Giant); 389 retval = dsw->d_gianttrick->d_close(dev, fflag, devtype, td); 390 mtx_unlock(&Giant); 391 dev_relthread(dev, ref); 392 return (retval); 393 } 394 395 static void 396 giant_strategy(struct bio *bp) 397 { 398 struct cdevsw *dsw; 399 struct cdev *dev; 400 int ref; 401 402 dev = bp->bio_dev; 403 dsw = dev_refthread(dev, &ref); 404 if (dsw == NULL) { 405 biofinish(bp, NULL, ENXIO); 406 return; 407 } 408 mtx_lock(&Giant); 409 dsw->d_gianttrick->d_strategy(bp); 410 mtx_unlock(&Giant); 411 dev_relthread(dev, ref); 412 } 413 414 static int 415 giant_ioctl(struct cdev *dev, u_long cmd, caddr_t data, int fflag, struct thread *td) 416 { 417 struct cdevsw *dsw; 418 int ref, retval; 419 420 dsw = dev_refthread(dev, &ref); 421 if (dsw == NULL) 422 return (ENXIO); 423 mtx_lock(&Giant); 424 retval = dsw->d_gianttrick->d_ioctl(dev, cmd, data, fflag, td); 425 mtx_unlock(&Giant); 426 dev_relthread(dev, ref); 427 return (retval); 428 } 429 430 static int 431 giant_read(struct cdev *dev, struct uio *uio, int ioflag) 432 { 433 struct cdevsw *dsw; 434 int ref, retval; 435 436 dsw = dev_refthread(dev, &ref); 437 if (dsw == NULL) 438 return (ENXIO); 439 mtx_lock(&Giant); 440 retval = dsw->d_gianttrick->d_read(dev, uio, ioflag); 441 mtx_unlock(&Giant); 442 dev_relthread(dev, ref); 443 return (retval); 444 } 445 446 static int 447 giant_write(struct cdev *dev, struct uio *uio, int ioflag) 448 { 449 struct cdevsw *dsw; 450 int ref, retval; 451 452 dsw = dev_refthread(dev, &ref); 453 if (dsw == NULL) 454 return (ENXIO); 455 mtx_lock(&Giant); 456 retval = dsw->d_gianttrick->d_write(dev, uio, ioflag); 457 mtx_unlock(&Giant); 458 dev_relthread(dev, ref); 459 return (retval); 460 } 461 462 static int 463 giant_poll(struct cdev *dev, int events, struct thread *td) 464 { 465 struct cdevsw *dsw; 466 int ref, retval; 467 468 dsw = dev_refthread(dev, &ref); 469 if (dsw == NULL) 470 return (ENXIO); 471 mtx_lock(&Giant); 472 retval = dsw->d_gianttrick->d_poll(dev, events, td); 473 mtx_unlock(&Giant); 474 dev_relthread(dev, ref); 475 return (retval); 476 } 477 478 static int 479 giant_kqfilter(struct cdev *dev, struct knote *kn) 480 { 481 struct cdevsw *dsw; 482 int ref, retval; 483 484 dsw = dev_refthread(dev, &ref); 485 if (dsw == NULL) 486 return (ENXIO); 487 mtx_lock(&Giant); 488 retval = dsw->d_gianttrick->d_kqfilter(dev, kn); 489 mtx_unlock(&Giant); 490 dev_relthread(dev, ref); 491 return (retval); 492 } 493 494 static int 495 giant_mmap(struct cdev *dev, vm_ooffset_t offset, vm_paddr_t *paddr, int nprot, 496 vm_memattr_t *memattr) 497 { 498 struct cdevsw *dsw; 499 int ref, retval; 500 501 dsw = dev_refthread(dev, &ref); 502 if (dsw == NULL) 503 return (ENXIO); 504 mtx_lock(&Giant); 505 retval = dsw->d_gianttrick->d_mmap(dev, offset, paddr, nprot, 506 memattr); 507 mtx_unlock(&Giant); 508 dev_relthread(dev, ref); 509 return (retval); 510 } 511 512 static int 513 giant_mmap_single(struct cdev *dev, vm_ooffset_t *offset, vm_size_t size, 514 vm_object_t *object, int nprot) 515 { 516 struct cdevsw *dsw; 517 int ref, retval; 518 519 dsw = dev_refthread(dev, &ref); 520 if (dsw == NULL) 521 return (ENXIO); 522 mtx_lock(&Giant); 523 retval = dsw->d_gianttrick->d_mmap_single(dev, offset, size, object, 524 nprot); 525 mtx_unlock(&Giant); 526 dev_relthread(dev, ref); 527 return (retval); 528 } 529 530 static void 531 notify(struct cdev *dev, const char *ev, int flags) 532 { 533 static const char prefix[] = "cdev="; 534 char *data; 535 int namelen, mflags; 536 537 if (cold) 538 return; 539 mflags = (flags & MAKEDEV_NOWAIT) ? M_NOWAIT : M_WAITOK; 540 namelen = strlen(dev->si_name); 541 data = malloc(namelen + sizeof(prefix), M_TEMP, mflags); 542 if (data == NULL) 543 return; 544 memcpy(data, prefix, sizeof(prefix) - 1); 545 memcpy(data + sizeof(prefix) - 1, dev->si_name, namelen + 1); 546 devctl_notify("DEVFS", "CDEV", ev, data); 547 free(data, M_TEMP); 548 } 549 550 static void 551 notify_create(struct cdev *dev, int flags) 552 { 553 554 notify(dev, "CREATE", flags); 555 } 556 557 static void 558 notify_destroy(struct cdev *dev) 559 { 560 561 notify(dev, "DESTROY", MAKEDEV_WAITOK); 562 } 563 564 static struct cdev * 565 newdev(struct make_dev_args *args, struct cdev *si) 566 { 567 struct cdev *si2; 568 struct cdevsw *csw; 569 570 dev_lock_assert_locked(); 571 csw = args->mda_devsw; 572 si2 = NULL; 573 if (csw->d_flags & D_NEEDMINOR) { 574 /* We may want to return an existing device */ 575 LIST_FOREACH(si2, &csw->d_devs, si_list) { 576 if (dev2unit(si2) == args->mda_unit) { 577 dev_free_devlocked(si); 578 si = si2; 579 break; 580 } 581 } 582 583 /* 584 * If we're returning an existing device, we should make sure 585 * it isn't already initialized. This would have been caught 586 * in consumers anyways, but it's good to catch such a case 587 * early. We still need to complete initialization of the 588 * device, and we'll use whatever make_dev_args were passed in 589 * to do so. 590 */ 591 KASSERT(si2 == NULL || (si2->si_flags & SI_NAMED) == 0, 592 ("make_dev() by driver %s on pre-existing device (min=%x, name=%s)", 593 args->mda_devsw->d_name, dev2unit(si2), devtoname(si2))); 594 } 595 si->si_drv0 = args->mda_unit; 596 si->si_drv1 = args->mda_si_drv1; 597 si->si_drv2 = args->mda_si_drv2; 598 /* Only push to csw->d_devs if it's not a cloned device. */ 599 if (si2 == NULL) { 600 si->si_devsw = csw; 601 LIST_INSERT_HEAD(&csw->d_devs, si, si_list); 602 } else { 603 KASSERT(si->si_devsw == csw, 604 ("%s: inconsistent devsw between clone_create() and make_dev()", 605 __func__)); 606 } 607 return (si); 608 } 609 610 static void 611 fini_cdevsw(struct cdevsw *devsw) 612 { 613 struct cdevsw *gt; 614 615 if (devsw->d_gianttrick != NULL) { 616 gt = devsw->d_gianttrick; 617 memcpy(devsw, gt, sizeof *devsw); 618 cdevsw_free_devlocked(gt); 619 devsw->d_gianttrick = NULL; 620 } 621 devsw->d_flags &= ~D_INIT; 622 } 623 624 static int 625 prep_cdevsw(struct cdevsw *devsw, int flags) 626 { 627 struct cdevsw *dsw2; 628 629 dev_lock_assert_locked(); 630 if (devsw->d_flags & D_INIT) 631 return (0); 632 if (devsw->d_flags & D_NEEDGIANT) { 633 dev_unlock(); 634 dsw2 = malloc(sizeof *dsw2, M_DEVT, 635 (flags & MAKEDEV_NOWAIT) ? M_NOWAIT : M_WAITOK); 636 dev_lock(); 637 if (dsw2 == NULL && !(devsw->d_flags & D_INIT)) 638 return (ENOMEM); 639 } else 640 dsw2 = NULL; 641 if (devsw->d_flags & D_INIT) { 642 if (dsw2 != NULL) 643 cdevsw_free_devlocked(dsw2); 644 return (0); 645 } 646 647 if (devsw->d_version != D_VERSION_04) { 648 printf( 649 "WARNING: Device driver \"%s\" has wrong version %s\n", 650 devsw->d_name == NULL ? "???" : devsw->d_name, 651 "and is disabled. Recompile KLD module."); 652 devsw->d_open = dead_open; 653 devsw->d_close = dead_close; 654 devsw->d_read = dead_read; 655 devsw->d_write = dead_write; 656 devsw->d_ioctl = dead_ioctl; 657 devsw->d_poll = dead_poll; 658 devsw->d_mmap = dead_mmap; 659 devsw->d_mmap_single = dead_mmap_single; 660 devsw->d_strategy = dead_strategy; 661 devsw->d_kqfilter = dead_kqfilter; 662 } 663 664 if ((devsw->d_flags & D_NEEDGIANT) != 0) { 665 if ((devsw->d_flags & D_GIANTOK) == 0) { 666 printf( 667 "WARNING: Device \"%s\" is Giant locked and may be " 668 "deleted before FreeBSD 14.0.\n", 669 devsw->d_name == NULL ? "???" : devsw->d_name); 670 } 671 if (devsw->d_gianttrick == NULL) { 672 memcpy(dsw2, devsw, sizeof *dsw2); 673 devsw->d_gianttrick = dsw2; 674 dsw2 = NULL; 675 } 676 } 677 678 #define FIXUP(member, noop, giant) \ 679 do { \ 680 if (devsw->member == NULL) { \ 681 devsw->member = noop; \ 682 } else if (devsw->d_flags & D_NEEDGIANT) \ 683 devsw->member = giant; \ 684 } \ 685 while (0) 686 687 FIXUP(d_open, null_open, giant_open); 688 FIXUP(d_fdopen, NULL, giant_fdopen); 689 FIXUP(d_close, null_close, giant_close); 690 FIXUP(d_read, no_read, giant_read); 691 FIXUP(d_write, no_write, giant_write); 692 FIXUP(d_ioctl, no_ioctl, giant_ioctl); 693 FIXUP(d_poll, no_poll, giant_poll); 694 FIXUP(d_mmap, no_mmap, giant_mmap); 695 FIXUP(d_strategy, no_strategy, giant_strategy); 696 FIXUP(d_kqfilter, no_kqfilter, giant_kqfilter); 697 FIXUP(d_mmap_single, no_mmap_single, giant_mmap_single); 698 699 LIST_INIT(&devsw->d_devs); 700 701 devsw->d_flags |= D_INIT; 702 703 if (dsw2 != NULL) 704 cdevsw_free_devlocked(dsw2); 705 return (0); 706 } 707 708 static int 709 prep_devname(struct cdev *dev, const char *fmt, va_list ap) 710 { 711 int len; 712 char *from, *q, *s, *to; 713 714 dev_lock_assert_locked(); 715 716 len = vsnrprintf(dev->si_name, sizeof(dev->si_name), 32, fmt, ap); 717 if (len > sizeof(dev->si_name) - 1) 718 return (ENAMETOOLONG); 719 720 /* Strip leading slashes. */ 721 for (from = dev->si_name; *from == '/'; from++) 722 ; 723 724 for (to = dev->si_name; *from != '\0'; from++, to++) { 725 /* 726 * Spaces and double quotation marks cause 727 * problems for the devctl(4) protocol. 728 * Reject names containing those characters. 729 */ 730 if (isspace(*from) || *from == '"') 731 return (EINVAL); 732 /* Treat multiple sequential slashes as single. */ 733 while (from[0] == '/' && from[1] == '/') 734 from++; 735 /* Trailing slash is considered invalid. */ 736 if (from[0] == '/' && from[1] == '\0') 737 return (EINVAL); 738 *to = *from; 739 } 740 *to = '\0'; 741 742 if (dev->si_name[0] == '\0') 743 return (EINVAL); 744 745 /* Disallow "." and ".." components. */ 746 for (s = dev->si_name;;) { 747 for (q = s; *q != '/' && *q != '\0'; q++) 748 ; 749 if (q - s == 1 && s[0] == '.') 750 return (EINVAL); 751 if (q - s == 2 && s[0] == '.' && s[1] == '.') 752 return (EINVAL); 753 if (*q != '/') 754 break; 755 s = q + 1; 756 } 757 758 if (devfs_dev_exists(dev->si_name) != 0) 759 return (EEXIST); 760 761 return (0); 762 } 763 764 void 765 make_dev_args_init_impl(struct make_dev_args *args, size_t sz) 766 { 767 768 bzero(args, sz); 769 args->mda_size = sz; 770 } 771 772 static int 773 make_dev_sv(struct make_dev_args *args1, struct cdev **dres, 774 const char *fmt, va_list ap) 775 { 776 struct cdev *dev, *dev_new; 777 struct make_dev_args args; 778 int res; 779 780 bzero(&args, sizeof(args)); 781 if (sizeof(args) < args1->mda_size) 782 return (EINVAL); 783 bcopy(args1, &args, args1->mda_size); 784 KASSERT((args.mda_flags & MAKEDEV_WAITOK) == 0 || 785 (args.mda_flags & MAKEDEV_NOWAIT) == 0, 786 ("make_dev_sv: both WAITOK and NOWAIT specified")); 787 dev_new = devfs_alloc(args.mda_flags); 788 if (dev_new == NULL) 789 return (ENOMEM); 790 dev_lock(); 791 res = prep_cdevsw(args.mda_devsw, args.mda_flags); 792 if (res != 0) { 793 dev_unlock(); 794 devfs_free(dev_new); 795 return (res); 796 } 797 dev = newdev(&args, dev_new); 798 if ((dev->si_flags & SI_NAMED) == 0) { 799 res = prep_devname(dev, fmt, ap); 800 if (res != 0) { 801 if ((args.mda_flags & MAKEDEV_CHECKNAME) == 0) { 802 panic( 803 "make_dev_sv: bad si_name (error=%d, si_name=%s)", 804 res, dev->si_name); 805 } 806 if (dev == dev_new) { 807 LIST_REMOVE(dev, si_list); 808 dev_unlock(); 809 devfs_free(dev); 810 } else 811 dev_unlock(); 812 return (res); 813 } 814 } 815 if ((args.mda_flags & MAKEDEV_REF) != 0) 816 dev_refl(dev); 817 if ((args.mda_flags & MAKEDEV_ETERNAL) != 0) 818 dev->si_flags |= SI_ETERNAL; 819 KASSERT(!(dev->si_flags & SI_NAMED), 820 ("make_dev() by driver %s on pre-existing device (min=%x, name=%s)", 821 args.mda_devsw->d_name, dev2unit(dev), devtoname(dev))); 822 dev->si_flags |= SI_NAMED; 823 if (args.mda_cr != NULL) 824 dev->si_cred = crhold(args.mda_cr); 825 dev->si_uid = args.mda_uid; 826 dev->si_gid = args.mda_gid; 827 dev->si_mode = args.mda_mode; 828 829 devfs_create(dev); 830 clean_unrhdrl(devfs_inos); 831 dev_unlock_and_free(); 832 833 notify_create(dev, args.mda_flags); 834 835 *dres = dev; 836 return (0); 837 } 838 839 int 840 make_dev_s(struct make_dev_args *args, struct cdev **dres, 841 const char *fmt, ...) 842 { 843 va_list ap; 844 int res; 845 846 va_start(ap, fmt); 847 res = make_dev_sv(args, dres, fmt, ap); 848 va_end(ap); 849 return (res); 850 } 851 852 static int 853 make_dev_credv(int flags, struct cdev **dres, struct cdevsw *devsw, int unit, 854 struct ucred *cr, uid_t uid, gid_t gid, int mode, const char *fmt, 855 va_list ap) 856 { 857 struct make_dev_args args; 858 859 make_dev_args_init(&args); 860 args.mda_flags = flags; 861 args.mda_devsw = devsw; 862 args.mda_cr = cr; 863 args.mda_uid = uid; 864 args.mda_gid = gid; 865 args.mda_mode = mode; 866 args.mda_unit = unit; 867 return (make_dev_sv(&args, dres, fmt, ap)); 868 } 869 870 struct cdev * 871 make_dev(struct cdevsw *devsw, int unit, uid_t uid, gid_t gid, int mode, 872 const char *fmt, ...) 873 { 874 struct cdev *dev; 875 va_list ap; 876 int res __unused; 877 878 va_start(ap, fmt); 879 res = make_dev_credv(0, &dev, devsw, unit, NULL, uid, gid, mode, fmt, 880 ap); 881 va_end(ap); 882 KASSERT(res == 0 && dev != NULL, 883 ("make_dev: failed make_dev_credv (error=%d)", res)); 884 return (dev); 885 } 886 887 struct cdev * 888 make_dev_cred(struct cdevsw *devsw, int unit, struct ucred *cr, uid_t uid, 889 gid_t gid, int mode, const char *fmt, ...) 890 { 891 struct cdev *dev; 892 va_list ap; 893 int res __unused; 894 895 va_start(ap, fmt); 896 res = make_dev_credv(0, &dev, devsw, unit, cr, uid, gid, mode, fmt, ap); 897 va_end(ap); 898 899 KASSERT(res == 0 && dev != NULL, 900 ("make_dev_cred: failed make_dev_credv (error=%d)", res)); 901 return (dev); 902 } 903 904 struct cdev * 905 make_dev_credf(int flags, struct cdevsw *devsw, int unit, struct ucred *cr, 906 uid_t uid, gid_t gid, int mode, const char *fmt, ...) 907 { 908 struct cdev *dev; 909 va_list ap; 910 int res; 911 912 va_start(ap, fmt); 913 res = make_dev_credv(flags, &dev, devsw, unit, cr, uid, gid, mode, 914 fmt, ap); 915 va_end(ap); 916 917 KASSERT(((flags & MAKEDEV_NOWAIT) != 0 && res == ENOMEM) || 918 ((flags & MAKEDEV_CHECKNAME) != 0 && res != ENOMEM) || res == 0, 919 ("make_dev_credf: failed make_dev_credv (error=%d)", res)); 920 return (res == 0 ? dev : NULL); 921 } 922 923 int 924 make_dev_p(int flags, struct cdev **cdev, struct cdevsw *devsw, 925 struct ucred *cr, uid_t uid, gid_t gid, int mode, const char *fmt, ...) 926 { 927 va_list ap; 928 int res; 929 930 va_start(ap, fmt); 931 res = make_dev_credv(flags, cdev, devsw, 0, cr, uid, gid, mode, 932 fmt, ap); 933 va_end(ap); 934 935 KASSERT(((flags & MAKEDEV_NOWAIT) != 0 && res == ENOMEM) || 936 ((flags & MAKEDEV_CHECKNAME) != 0 && res != ENOMEM) || res == 0, 937 ("make_dev_p: failed make_dev_credv (error=%d)", res)); 938 return (res); 939 } 940 941 static void 942 dev_dependsl(struct cdev *pdev, struct cdev *cdev) 943 { 944 945 cdev->si_parent = pdev; 946 cdev->si_flags |= SI_CHILD; 947 LIST_INSERT_HEAD(&pdev->si_children, cdev, si_siblings); 948 } 949 950 void 951 dev_depends(struct cdev *pdev, struct cdev *cdev) 952 { 953 954 dev_lock(); 955 dev_dependsl(pdev, cdev); 956 dev_unlock(); 957 } 958 959 static int 960 make_dev_alias_v(int flags, struct cdev **cdev, struct cdev *pdev, 961 const char *fmt, va_list ap) 962 { 963 struct cdev *dev; 964 int error; 965 966 KASSERT(pdev != NULL, ("make_dev_alias_v: pdev is NULL")); 967 KASSERT((flags & MAKEDEV_WAITOK) == 0 || (flags & MAKEDEV_NOWAIT) == 0, 968 ("make_dev_alias_v: both WAITOK and NOWAIT specified")); 969 KASSERT((flags & ~(MAKEDEV_WAITOK | MAKEDEV_NOWAIT | 970 MAKEDEV_CHECKNAME)) == 0, 971 ("make_dev_alias_v: invalid flags specified (flags=%02x)", flags)); 972 973 dev = devfs_alloc(flags); 974 if (dev == NULL) 975 return (ENOMEM); 976 dev_lock(); 977 dev->si_flags |= SI_ALIAS; 978 error = prep_devname(dev, fmt, ap); 979 if (error != 0) { 980 if ((flags & MAKEDEV_CHECKNAME) == 0) { 981 panic("make_dev_alias_v: bad si_name " 982 "(error=%d, si_name=%s)", error, dev->si_name); 983 } 984 dev_unlock(); 985 devfs_free(dev); 986 return (error); 987 } 988 dev->si_flags |= SI_NAMED; 989 devfs_create(dev); 990 dev_dependsl(pdev, dev); 991 clean_unrhdrl(devfs_inos); 992 dev_unlock(); 993 994 notify_create(dev, flags); 995 *cdev = dev; 996 997 return (0); 998 } 999 1000 struct cdev * 1001 make_dev_alias(struct cdev *pdev, const char *fmt, ...) 1002 { 1003 struct cdev *dev; 1004 va_list ap; 1005 int res __unused; 1006 1007 va_start(ap, fmt); 1008 res = make_dev_alias_v(MAKEDEV_WAITOK, &dev, pdev, fmt, ap); 1009 va_end(ap); 1010 1011 KASSERT(res == 0 && dev != NULL, 1012 ("make_dev_alias: failed make_dev_alias_v (error=%d)", res)); 1013 return (dev); 1014 } 1015 1016 int 1017 make_dev_alias_p(int flags, struct cdev **cdev, struct cdev *pdev, 1018 const char *fmt, ...) 1019 { 1020 va_list ap; 1021 int res; 1022 1023 va_start(ap, fmt); 1024 res = make_dev_alias_v(flags, cdev, pdev, fmt, ap); 1025 va_end(ap); 1026 return (res); 1027 } 1028 1029 int 1030 make_dev_physpath_alias(int flags, struct cdev **cdev, struct cdev *pdev, 1031 struct cdev *old_alias, const char *physpath) 1032 { 1033 char *devfspath; 1034 int physpath_len; 1035 int max_parentpath_len; 1036 int parentpath_len; 1037 int devfspathbuf_len; 1038 int mflags; 1039 int ret; 1040 1041 *cdev = NULL; 1042 devfspath = NULL; 1043 physpath_len = strlen(physpath); 1044 ret = EINVAL; 1045 if (physpath_len == 0) 1046 goto out; 1047 1048 if (strncmp("id1,", physpath, 4) == 0) { 1049 physpath += 4; 1050 physpath_len -= 4; 1051 if (physpath_len == 0) 1052 goto out; 1053 } 1054 1055 max_parentpath_len = SPECNAMELEN - physpath_len - /*/*/1; 1056 parentpath_len = strlen(pdev->si_name); 1057 if (max_parentpath_len < parentpath_len) { 1058 if (bootverbose) 1059 printf("WARNING: Unable to alias %s " 1060 "to %s/%s - path too long\n", 1061 pdev->si_name, physpath, pdev->si_name); 1062 ret = ENAMETOOLONG; 1063 goto out; 1064 } 1065 1066 mflags = (flags & MAKEDEV_NOWAIT) ? M_NOWAIT : M_WAITOK; 1067 devfspathbuf_len = physpath_len + /*/*/1 + parentpath_len + /*NUL*/1; 1068 devfspath = malloc(devfspathbuf_len, M_DEVBUF, mflags); 1069 if (devfspath == NULL) { 1070 ret = ENOMEM; 1071 goto out; 1072 } 1073 1074 sprintf(devfspath, "%s/%s", physpath, pdev->si_name); 1075 if (old_alias != NULL && strcmp(old_alias->si_name, devfspath) == 0) { 1076 /* Retain the existing alias. */ 1077 *cdev = old_alias; 1078 old_alias = NULL; 1079 ret = 0; 1080 } else { 1081 ret = make_dev_alias_p(flags, cdev, pdev, "%s", devfspath); 1082 } 1083 out: 1084 if (old_alias != NULL) 1085 destroy_dev(old_alias); 1086 if (devfspath != NULL) 1087 free(devfspath, M_DEVBUF); 1088 return (ret); 1089 } 1090 1091 static void 1092 destroy_devl(struct cdev *dev) 1093 { 1094 struct cdevsw *csw; 1095 struct cdev_privdata *p; 1096 struct cdev_priv *cdp; 1097 1098 dev_lock_assert_locked(); 1099 KASSERT(dev->si_flags & SI_NAMED, 1100 ("WARNING: Driver mistake: destroy_dev on %d\n", dev2unit(dev))); 1101 KASSERT((dev->si_flags & SI_ETERNAL) == 0, 1102 ("WARNING: Driver mistake: destroy_dev on eternal %d\n", 1103 dev2unit(dev))); 1104 1105 cdp = cdev2priv(dev); 1106 if ((cdp->cdp_flags & CDP_UNREF_DTR) == 0) { 1107 /* 1108 * Avoid race with dev_rel(), e.g. from the populate 1109 * loop. If CDP_UNREF_DTR flag is set, the reference 1110 * to be dropped at the end of destroy_devl() was 1111 * already taken by delist_dev_locked(). 1112 */ 1113 dev_refl(dev); 1114 1115 devfs_destroy(dev); 1116 } 1117 1118 /* Remove name marking */ 1119 dev->si_flags &= ~SI_NAMED; 1120 1121 /* If we are a child, remove us from the parents list */ 1122 if (dev->si_flags & SI_CHILD) { 1123 LIST_REMOVE(dev, si_siblings); 1124 dev->si_flags &= ~SI_CHILD; 1125 } 1126 1127 /* Kill our children */ 1128 while (!LIST_EMPTY(&dev->si_children)) 1129 destroy_devl(LIST_FIRST(&dev->si_children)); 1130 1131 /* Remove from clone list */ 1132 if (dev->si_flags & SI_CLONELIST) { 1133 LIST_REMOVE(dev, si_clone); 1134 dev->si_flags &= ~SI_CLONELIST; 1135 } 1136 1137 mtx_lock(&cdp->cdp_threadlock); 1138 csw = dev->si_devsw; 1139 dev->si_devsw = NULL; /* already NULL for SI_ALIAS */ 1140 while (csw != NULL && csw->d_purge != NULL && dev->si_threadcount) { 1141 csw->d_purge(dev); 1142 mtx_unlock(&cdp->cdp_threadlock); 1143 msleep(csw, &devmtx, PRIBIO, "devprg", hz/10); 1144 mtx_lock(&cdp->cdp_threadlock); 1145 if (dev->si_threadcount) 1146 printf("Still %lu threads in %s\n", 1147 dev->si_threadcount, devtoname(dev)); 1148 } 1149 while (dev->si_threadcount != 0) { 1150 /* Use unique dummy wait ident */ 1151 mtx_unlock(&cdp->cdp_threadlock); 1152 msleep(&csw, &devmtx, PRIBIO, "devdrn", hz / 10); 1153 mtx_lock(&cdp->cdp_threadlock); 1154 } 1155 1156 mtx_unlock(&cdp->cdp_threadlock); 1157 dev_unlock(); 1158 if ((cdp->cdp_flags & CDP_UNREF_DTR) == 0) { 1159 /* avoid out of order notify events */ 1160 notify_destroy(dev); 1161 } 1162 mtx_lock(&cdevpriv_mtx); 1163 while ((p = LIST_FIRST(&cdp->cdp_fdpriv)) != NULL) { 1164 devfs_destroy_cdevpriv(p); 1165 mtx_lock(&cdevpriv_mtx); 1166 } 1167 mtx_unlock(&cdevpriv_mtx); 1168 dev_lock(); 1169 1170 dev->si_drv1 = 0; 1171 dev->si_drv2 = 0; 1172 1173 if (!(dev->si_flags & SI_ALIAS)) { 1174 /* Remove from cdevsw list */ 1175 LIST_REMOVE(dev, si_list); 1176 1177 /* If cdevsw has no more struct cdev *'s, clean it */ 1178 if (LIST_EMPTY(&csw->d_devs)) { 1179 fini_cdevsw(csw); 1180 wakeup(&csw->d_devs); 1181 } 1182 } 1183 dev->si_flags &= ~SI_ALIAS; 1184 cdp->cdp_flags &= ~CDP_UNREF_DTR; 1185 dev->si_refcount--; 1186 1187 if (dev->si_refcount > 0) 1188 LIST_INSERT_HEAD(&dead_cdevsw.d_devs, dev, si_list); 1189 else 1190 dev_free_devlocked(dev); 1191 } 1192 1193 static void 1194 delist_dev_locked(struct cdev *dev) 1195 { 1196 struct cdev_priv *cdp; 1197 struct cdev *child; 1198 1199 dev_lock_assert_locked(); 1200 cdp = cdev2priv(dev); 1201 if ((cdp->cdp_flags & CDP_UNREF_DTR) != 0) 1202 return; 1203 cdp->cdp_flags |= CDP_UNREF_DTR; 1204 dev_refl(dev); 1205 devfs_destroy(dev); 1206 LIST_FOREACH(child, &dev->si_children, si_siblings) 1207 delist_dev_locked(child); 1208 dev_unlock(); 1209 /* ensure the destroy event is queued in order */ 1210 notify_destroy(dev); 1211 dev_lock(); 1212 } 1213 1214 /* 1215 * This function will delist a character device and its children from 1216 * the directory listing and create a destroy event without waiting 1217 * for all character device references to go away. At some later point 1218 * destroy_dev() must be called to complete the character device 1219 * destruction. After calling this function the character device name 1220 * can instantly be re-used. 1221 */ 1222 void 1223 delist_dev(struct cdev *dev) 1224 { 1225 1226 WITNESS_WARN(WARN_GIANTOK | WARN_SLEEPOK, NULL, "delist_dev"); 1227 dev_lock(); 1228 delist_dev_locked(dev); 1229 dev_unlock(); 1230 } 1231 1232 void 1233 destroy_dev(struct cdev *dev) 1234 { 1235 1236 WITNESS_WARN(WARN_GIANTOK | WARN_SLEEPOK, NULL, "destroy_dev"); 1237 dev_lock(); 1238 destroy_devl(dev); 1239 dev_unlock_and_free(); 1240 } 1241 1242 const char * 1243 devtoname(struct cdev *dev) 1244 { 1245 1246 return (dev->si_name); 1247 } 1248 1249 int 1250 dev_stdclone(char *name, char **namep, const char *stem, int *unit) 1251 { 1252 int u, i; 1253 1254 i = strlen(stem); 1255 if (strncmp(stem, name, i) != 0) 1256 return (0); 1257 if (!isdigit(name[i])) 1258 return (0); 1259 u = 0; 1260 if (name[i] == '0' && isdigit(name[i+1])) 1261 return (0); 1262 while (isdigit(name[i])) { 1263 u *= 10; 1264 u += name[i++] - '0'; 1265 } 1266 if (u > 0xffffff) 1267 return (0); 1268 *unit = u; 1269 if (namep) 1270 *namep = &name[i]; 1271 if (name[i]) 1272 return (2); 1273 return (1); 1274 } 1275 1276 /* 1277 * Helper functions for cloning device drivers. 1278 * 1279 * The objective here is to make it unnecessary for the device drivers to 1280 * use rman or similar to manage their unit number space. Due to the way 1281 * we do "on-demand" devices, using rman or other "private" methods 1282 * will be very tricky to lock down properly once we lock down this file. 1283 * 1284 * Instead we give the drivers these routines which puts the struct cdev *'s 1285 * that are to be managed on their own list, and gives the driver the ability 1286 * to ask for the first free unit number or a given specified unit number. 1287 * 1288 * In addition these routines support paired devices (pty, nmdm and similar) 1289 * by respecting a number of "flag" bits in the minor number. 1290 * 1291 */ 1292 1293 struct clonedevs { 1294 LIST_HEAD(,cdev) head; 1295 }; 1296 1297 void 1298 clone_setup(struct clonedevs **cdp) 1299 { 1300 1301 *cdp = malloc(sizeof **cdp, M_DEVBUF, M_WAITOK | M_ZERO); 1302 LIST_INIT(&(*cdp)->head); 1303 } 1304 1305 int 1306 clone_create(struct clonedevs **cdp, struct cdevsw *csw, int *up, 1307 struct cdev **dp, int extra) 1308 { 1309 struct clonedevs *cd; 1310 struct cdev *dev, *ndev, *dl, *de; 1311 struct make_dev_args args; 1312 int unit, low, u; 1313 1314 KASSERT(*cdp != NULL, 1315 ("clone_setup() not called in driver \"%s\"", csw->d_name)); 1316 KASSERT(!(extra & CLONE_UNITMASK), 1317 ("Illegal extra bits (0x%x) in clone_create", extra)); 1318 KASSERT(*up <= CLONE_UNITMASK, 1319 ("Too high unit (0x%x) in clone_create", *up)); 1320 KASSERT(csw->d_flags & D_NEEDMINOR, 1321 ("clone_create() on cdevsw without minor numbers")); 1322 1323 /* 1324 * Search the list for a lot of things in one go: 1325 * A preexisting match is returned immediately. 1326 * The lowest free unit number if we are passed -1, and the place 1327 * in the list where we should insert that new element. 1328 * The place to insert a specified unit number, if applicable 1329 * the end of the list. 1330 */ 1331 unit = *up; 1332 ndev = devfs_alloc(MAKEDEV_WAITOK); 1333 dev_lock(); 1334 prep_cdevsw(csw, MAKEDEV_WAITOK); 1335 low = extra; 1336 de = dl = NULL; 1337 cd = *cdp; 1338 LIST_FOREACH(dev, &cd->head, si_clone) { 1339 KASSERT(dev->si_flags & SI_CLONELIST, 1340 ("Dev %p(%s) should be on clonelist", dev, dev->si_name)); 1341 u = dev2unit(dev); 1342 if (u == (unit | extra)) { 1343 *dp = dev; 1344 dev_unlock(); 1345 devfs_free(ndev); 1346 return (0); 1347 } 1348 if (unit == -1 && u == low) { 1349 low++; 1350 de = dev; 1351 continue; 1352 } else if (u < (unit | extra)) { 1353 de = dev; 1354 continue; 1355 } else if (u > (unit | extra)) { 1356 dl = dev; 1357 break; 1358 } 1359 } 1360 if (unit == -1) 1361 unit = low & CLONE_UNITMASK; 1362 make_dev_args_init(&args); 1363 args.mda_unit = unit | extra; 1364 args.mda_devsw = csw; 1365 dev = newdev(&args, ndev); 1366 if (dev->si_flags & SI_CLONELIST) { 1367 printf("dev %p (%s) is on clonelist\n", dev, dev->si_name); 1368 printf("unit=%d, low=%d, extra=0x%x\n", unit, low, extra); 1369 LIST_FOREACH(dev, &cd->head, si_clone) { 1370 printf("\t%p %s\n", dev, dev->si_name); 1371 } 1372 panic("foo"); 1373 } 1374 KASSERT(!(dev->si_flags & SI_CLONELIST), 1375 ("Dev %p(%s) should not be on clonelist", dev, dev->si_name)); 1376 if (dl != NULL) 1377 LIST_INSERT_BEFORE(dl, dev, si_clone); 1378 else if (de != NULL) 1379 LIST_INSERT_AFTER(de, dev, si_clone); 1380 else 1381 LIST_INSERT_HEAD(&cd->head, dev, si_clone); 1382 dev->si_flags |= SI_CLONELIST; 1383 *up = unit; 1384 dev_unlock_and_free(); 1385 return (1); 1386 } 1387 1388 /* 1389 * Kill everything still on the list. The driver should already have 1390 * disposed of any softc hung of the struct cdev *'s at this time. 1391 */ 1392 void 1393 clone_cleanup(struct clonedevs **cdp) 1394 { 1395 struct cdev *dev; 1396 struct cdev_priv *cp; 1397 struct clonedevs *cd; 1398 1399 cd = *cdp; 1400 if (cd == NULL) 1401 return; 1402 dev_lock(); 1403 while (!LIST_EMPTY(&cd->head)) { 1404 dev = LIST_FIRST(&cd->head); 1405 LIST_REMOVE(dev, si_clone); 1406 KASSERT(dev->si_flags & SI_CLONELIST, 1407 ("Dev %p(%s) should be on clonelist", dev, dev->si_name)); 1408 dev->si_flags &= ~SI_CLONELIST; 1409 cp = cdev2priv(dev); 1410 if (!(cp->cdp_flags & CDP_SCHED_DTR)) { 1411 cp->cdp_flags |= CDP_SCHED_DTR; 1412 KASSERT(dev->si_flags & SI_NAMED, 1413 ("Driver has goofed in cloning underways udev %jx unit %x", 1414 (uintmax_t)dev2udev(dev), dev2unit(dev))); 1415 destroy_devl(dev); 1416 } 1417 } 1418 dev_unlock_and_free(); 1419 free(cd, M_DEVBUF); 1420 *cdp = NULL; 1421 } 1422 1423 static TAILQ_HEAD(, cdev_priv) dev_ddtr = 1424 TAILQ_HEAD_INITIALIZER(dev_ddtr); 1425 static TAILQ_HEAD(, cdev_priv) dev_ddtr_giant = 1426 TAILQ_HEAD_INITIALIZER(dev_ddtr_giant); 1427 static struct task dev_dtr_task = TASK_INITIALIZER(0, destroy_dev_tq, &dev_ddtr); 1428 static struct task dev_dtr_task_giant = TASK_INITIALIZER(0, destroy_dev_tq_giant, 1429 &dev_ddtr_giant); 1430 1431 static void 1432 destroy_dev_tq(void *ctx, int pending) 1433 { 1434 TAILQ_HEAD(, cdev_priv) *ddtr = ctx; 1435 struct cdev_priv *cp; 1436 struct cdev *dev; 1437 void (*cb)(void *); 1438 void *cb_arg; 1439 1440 dev_lock(); 1441 while (!TAILQ_EMPTY(ddtr)) { 1442 cp = TAILQ_FIRST(ddtr); 1443 dev = &cp->cdp_c; 1444 KASSERT(cp->cdp_flags & CDP_SCHED_DTR, 1445 ("cdev %p in dev_destroy_tq without CDP_SCHED_DTR", cp)); 1446 TAILQ_REMOVE(ddtr, cp, cdp_dtr_list); 1447 cb = cp->cdp_dtr_cb; 1448 cb_arg = cp->cdp_dtr_cb_arg; 1449 destroy_devl(dev); 1450 dev_unlock_and_free(); 1451 dev_rel(dev); 1452 if (cb != NULL) 1453 cb(cb_arg); 1454 dev_lock(); 1455 } 1456 dev_unlock(); 1457 } 1458 1459 static void 1460 destroy_dev_tq_giant(void *ctx, int pending) 1461 { 1462 mtx_lock(&Giant); 1463 destroy_dev_tq(ctx, pending); 1464 mtx_unlock(&Giant); 1465 } 1466 1467 /* 1468 * devmtx shall be locked on entry. devmtx will be unlocked after 1469 * function return. 1470 */ 1471 static int 1472 destroy_dev_sched_cbl(struct cdev *dev, void (*cb)(void *), void *arg) 1473 { 1474 struct cdev_priv *cp; 1475 bool need_giant; 1476 1477 dev_lock_assert_locked(); 1478 cp = cdev2priv(dev); 1479 if (cp->cdp_flags & CDP_SCHED_DTR) { 1480 dev_unlock(); 1481 return (0); 1482 } 1483 dev_refl(dev); 1484 cp->cdp_flags |= CDP_SCHED_DTR; 1485 cp->cdp_dtr_cb = cb; 1486 cp->cdp_dtr_cb_arg = arg; 1487 need_giant = (dev->si_devsw->d_flags & D_NEEDGIANT) != 0; 1488 if (need_giant) 1489 TAILQ_INSERT_TAIL(&dev_ddtr_giant, cp, cdp_dtr_list); 1490 else 1491 TAILQ_INSERT_TAIL(&dev_ddtr, cp, cdp_dtr_list); 1492 dev_unlock(); 1493 if (need_giant) 1494 taskqueue_enqueue(taskqueue_thread, &dev_dtr_task_giant); 1495 else 1496 taskqueue_enqueue(taskqueue_thread, &dev_dtr_task); 1497 return (1); 1498 } 1499 1500 int 1501 destroy_dev_sched_cb(struct cdev *dev, void (*cb)(void *), void *arg) 1502 { 1503 1504 dev_lock(); 1505 return (destroy_dev_sched_cbl(dev, cb, arg)); 1506 } 1507 1508 int 1509 destroy_dev_sched(struct cdev *dev) 1510 { 1511 1512 return (destroy_dev_sched_cb(dev, NULL, NULL)); 1513 } 1514 1515 void 1516 destroy_dev_drain(struct cdevsw *csw) 1517 { 1518 1519 dev_lock(); 1520 while (!LIST_EMPTY(&csw->d_devs)) { 1521 msleep(&csw->d_devs, &devmtx, PRIBIO, "devscd", hz/10); 1522 } 1523 dev_unlock(); 1524 } 1525 1526 #include "opt_ddb.h" 1527 #ifdef DDB 1528 #include <sys/kernel.h> 1529 1530 #include <ddb/ddb.h> 1531 1532 DB_SHOW_COMMAND(cdev, db_show_cdev) 1533 { 1534 struct cdev_priv *cdp; 1535 struct cdev *dev; 1536 u_int flags; 1537 char buf[512]; 1538 1539 if (!have_addr) { 1540 TAILQ_FOREACH(cdp, &cdevp_list, cdp_list) { 1541 dev = &cdp->cdp_c; 1542 db_printf("%s %p\n", dev->si_name, dev); 1543 if (db_pager_quit) 1544 break; 1545 } 1546 return; 1547 } 1548 1549 dev = (struct cdev *)addr; 1550 cdp = cdev2priv(dev); 1551 db_printf("dev %s ref %d use %ld thr %ld inuse %u fdpriv %p\n", 1552 dev->si_name, dev->si_refcount, dev->si_usecount, 1553 dev->si_threadcount, cdp->cdp_inuse, cdp->cdp_fdpriv.lh_first); 1554 db_printf("devsw %p si_drv0 %d si_drv1 %p si_drv2 %p\n", 1555 dev->si_devsw, dev->si_drv0, dev->si_drv1, dev->si_drv2); 1556 flags = dev->si_flags; 1557 #define SI_FLAG(flag) do { \ 1558 if (flags & (flag)) { \ 1559 if (buf[0] != '\0') \ 1560 strlcat(buf, ", ", sizeof(buf)); \ 1561 strlcat(buf, (#flag) + 3, sizeof(buf)); \ 1562 flags &= ~(flag); \ 1563 } \ 1564 } while (0) 1565 buf[0] = '\0'; 1566 SI_FLAG(SI_ETERNAL); 1567 SI_FLAG(SI_ALIAS); 1568 SI_FLAG(SI_NAMED); 1569 SI_FLAG(SI_CHILD); 1570 SI_FLAG(SI_DUMPDEV); 1571 SI_FLAG(SI_CLONELIST); 1572 db_printf("si_flags %s\n", buf); 1573 1574 flags = cdp->cdp_flags; 1575 #define CDP_FLAG(flag) do { \ 1576 if (flags & (flag)) { \ 1577 if (buf[0] != '\0') \ 1578 strlcat(buf, ", ", sizeof(buf)); \ 1579 strlcat(buf, (#flag) + 4, sizeof(buf)); \ 1580 flags &= ~(flag); \ 1581 } \ 1582 } while (0) 1583 buf[0] = '\0'; 1584 CDP_FLAG(CDP_ACTIVE); 1585 CDP_FLAG(CDP_SCHED_DTR); 1586 db_printf("cdp_flags %s\n", buf); 1587 } 1588 #endif 1589