1 /*- 2 * SPDX-License-Identifier: BSD-2-Clause 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 #include <sys/param.h> 31 #include <sys/kernel.h> 32 #include <sys/systm.h> 33 #include <sys/bio.h> 34 #include <sys/devctl.h> 35 #include <sys/lock.h> 36 #include <sys/mutex.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/sx.h> 44 #include <sys/ctype.h> 45 #include <sys/ucred.h> 46 #include <sys/taskqueue.h> 47 #include <machine/stdarg.h> 48 49 #include <fs/devfs/devfs_int.h> 50 #include <vm/vm.h> 51 52 static MALLOC_DEFINE(M_DEVT, "cdev", "cdev storage"); 53 54 struct mtx devmtx; 55 static void destroy_devl(struct cdev *dev); 56 static int destroy_dev_sched_cbl(struct cdev *dev, 57 void (*cb)(void *), void *arg); 58 static void destroy_dev_tq(void *ctx, int pending); 59 static void destroy_dev_tq_giant(void *ctx, int pending); 60 static int make_dev_credv(int flags, struct cdev **dres, struct cdevsw *devsw, 61 int unit, struct ucred *cr, uid_t uid, gid_t gid, int mode, const char *fmt, 62 va_list ap); 63 64 static struct cdev_priv_list cdevp_free_list = 65 TAILQ_HEAD_INITIALIZER(cdevp_free_list); 66 static SLIST_HEAD(free_cdevsw, cdevsw) cdevsw_gt_post_list = 67 SLIST_HEAD_INITIALIZER(cdevsw_gt_post_list); 68 69 void 70 dev_lock(void) 71 { 72 73 mtx_lock(&devmtx); 74 } 75 76 /* 77 * Free all the memory collected while the cdev mutex was 78 * locked. Since devmtx is after the system map mutex, free() cannot 79 * be called immediately and is postponed until cdev mutex can be 80 * dropped. 81 */ 82 static void 83 dev_unlock_and_free(void) 84 { 85 struct cdev_priv_list cdp_free; 86 struct free_cdevsw csw_free; 87 struct cdev_priv *cdp; 88 struct cdevsw *csw; 89 90 dev_lock_assert_locked(); 91 92 /* 93 * Make the local copy of the list heads while the dev_mtx is 94 * held. Free it later. 95 */ 96 TAILQ_INIT(&cdp_free); 97 TAILQ_CONCAT(&cdp_free, &cdevp_free_list, cdp_list); 98 csw_free = cdevsw_gt_post_list; 99 SLIST_INIT(&cdevsw_gt_post_list); 100 101 mtx_unlock(&devmtx); 102 103 while ((cdp = TAILQ_FIRST(&cdp_free)) != NULL) { 104 TAILQ_REMOVE(&cdp_free, cdp, cdp_list); 105 devfs_free(&cdp->cdp_c); 106 } 107 while ((csw = SLIST_FIRST(&csw_free)) != NULL) { 108 SLIST_REMOVE_HEAD(&csw_free, d_postfree_list); 109 free(csw, M_DEVT); 110 } 111 } 112 113 static void 114 dev_free_devlocked(struct cdev *cdev) 115 { 116 struct cdev_priv *cdp; 117 118 dev_lock_assert_locked(); 119 cdp = cdev2priv(cdev); 120 KASSERT((cdp->cdp_flags & CDP_UNREF_DTR) == 0, 121 ("destroy_dev() was not called after delist_dev(%p)", cdev)); 122 TAILQ_INSERT_HEAD(&cdevp_free_list, cdp, cdp_list); 123 } 124 125 static void 126 cdevsw_free_devlocked(struct cdevsw *csw) 127 { 128 129 dev_lock_assert_locked(); 130 SLIST_INSERT_HEAD(&cdevsw_gt_post_list, csw, d_postfree_list); 131 } 132 133 void 134 dev_unlock(void) 135 { 136 137 mtx_unlock(&devmtx); 138 } 139 140 void 141 dev_ref(struct cdev *dev) 142 { 143 144 dev_lock_assert_unlocked(); 145 mtx_lock(&devmtx); 146 dev->si_refcount++; 147 mtx_unlock(&devmtx); 148 } 149 150 void 151 dev_refl(struct cdev *dev) 152 { 153 154 dev_lock_assert_locked(); 155 dev->si_refcount++; 156 } 157 158 void 159 dev_rel(struct cdev *dev) 160 { 161 int flag = 0; 162 163 dev_lock_assert_unlocked(); 164 dev_lock(); 165 dev->si_refcount--; 166 KASSERT(dev->si_refcount >= 0, 167 ("dev_rel(%s) gave negative count", devtoname(dev))); 168 if (dev->si_devsw == NULL && dev->si_refcount == 0) { 169 LIST_REMOVE(dev, si_list); 170 flag = 1; 171 } 172 dev_unlock(); 173 if (flag) 174 devfs_free(dev); 175 } 176 177 struct cdevsw * 178 dev_refthread(struct cdev *dev, int *ref) 179 { 180 struct cdevsw *csw; 181 struct cdev_priv *cdp; 182 183 dev_lock_assert_unlocked(); 184 if ((dev->si_flags & SI_ETERNAL) != 0) { 185 *ref = 0; 186 return (dev->si_devsw); 187 } 188 cdp = cdev2priv(dev); 189 mtx_lock(&cdp->cdp_threadlock); 190 csw = dev->si_devsw; 191 if (csw != NULL) { 192 if ((cdp->cdp_flags & CDP_SCHED_DTR) == 0) 193 atomic_add_long(&dev->si_threadcount, 1); 194 else 195 csw = NULL; 196 } 197 mtx_unlock(&cdp->cdp_threadlock); 198 if (csw != NULL) 199 *ref = 1; 200 return (csw); 201 } 202 203 struct cdevsw * 204 devvn_refthread(struct vnode *vp, struct cdev **devp, int *ref) 205 { 206 struct cdevsw *csw; 207 struct cdev_priv *cdp; 208 struct cdev *dev; 209 210 dev_lock_assert_unlocked(); 211 if ((vp->v_vflag & VV_ETERNALDEV) != 0) { 212 dev = vp->v_rdev; 213 if (dev == NULL) 214 return (NULL); 215 KASSERT((dev->si_flags & SI_ETERNAL) != 0, 216 ("Not eternal cdev")); 217 *ref = 0; 218 csw = dev->si_devsw; 219 KASSERT(csw != NULL, ("Eternal cdev is destroyed")); 220 *devp = dev; 221 return (csw); 222 } 223 224 csw = NULL; 225 VI_LOCK(vp); 226 dev = vp->v_rdev; 227 if (dev == NULL) { 228 VI_UNLOCK(vp); 229 return (NULL); 230 } 231 cdp = cdev2priv(dev); 232 mtx_lock(&cdp->cdp_threadlock); 233 if ((cdp->cdp_flags & CDP_SCHED_DTR) == 0) { 234 csw = dev->si_devsw; 235 if (csw != NULL) 236 atomic_add_long(&dev->si_threadcount, 1); 237 } 238 mtx_unlock(&cdp->cdp_threadlock); 239 VI_UNLOCK(vp); 240 if (csw != NULL) { 241 *devp = dev; 242 *ref = 1; 243 } 244 return (csw); 245 } 246 247 void 248 dev_relthread(struct cdev *dev, int ref) 249 { 250 251 dev_lock_assert_unlocked(); 252 if (!ref) 253 return; 254 KASSERT(dev->si_threadcount > 0, 255 ("%s threadcount is wrong", dev->si_name)); 256 atomic_subtract_rel_long(&dev->si_threadcount, 1); 257 } 258 259 int 260 nullop(void) 261 { 262 263 return (0); 264 } 265 266 int 267 eopnotsupp(void) 268 { 269 270 return (EOPNOTSUPP); 271 } 272 273 static int 274 enxio(void) 275 { 276 return (ENXIO); 277 } 278 279 static int 280 enodev(void) 281 { 282 return (ENODEV); 283 } 284 285 /* Define a dead_cdevsw for use when devices leave unexpectedly. */ 286 287 #define dead_open (d_open_t *)enxio 288 #define dead_close (d_close_t *)enxio 289 #define dead_read (d_read_t *)enxio 290 #define dead_write (d_write_t *)enxio 291 #define dead_ioctl (d_ioctl_t *)enxio 292 #define dead_poll (d_poll_t *)enodev 293 #define dead_mmap (d_mmap_t *)enodev 294 295 static void 296 dead_strategy(struct bio *bp) 297 { 298 299 biofinish(bp, NULL, ENXIO); 300 } 301 302 #define dead_kqfilter (d_kqfilter_t *)enxio 303 #define dead_mmap_single (d_mmap_single_t *)enodev 304 305 static struct cdevsw dead_cdevsw = { 306 .d_version = D_VERSION, 307 .d_open = dead_open, 308 .d_close = dead_close, 309 .d_read = dead_read, 310 .d_write = dead_write, 311 .d_ioctl = dead_ioctl, 312 .d_poll = dead_poll, 313 .d_mmap = dead_mmap, 314 .d_strategy = dead_strategy, 315 .d_name = "dead", 316 .d_kqfilter = dead_kqfilter, 317 .d_mmap_single = dead_mmap_single 318 }; 319 320 /* Default methods if driver does not specify method */ 321 322 #define null_open (d_open_t *)nullop 323 #define null_close (d_close_t *)nullop 324 #define no_read (d_read_t *)enodev 325 #define no_write (d_write_t *)enodev 326 #define no_ioctl (d_ioctl_t *)enodev 327 #define no_mmap (d_mmap_t *)enodev 328 #define no_kqfilter (d_kqfilter_t *)enodev 329 #define no_mmap_single (d_mmap_single_t *)enodev 330 331 static void 332 no_strategy(struct bio *bp) 333 { 334 335 biofinish(bp, NULL, ENODEV); 336 } 337 338 static int 339 no_poll(struct cdev *dev __unused, int events, struct thread *td __unused) 340 { 341 342 return (poll_no_poll(events)); 343 } 344 345 static int 346 giant_open(struct cdev *dev, int oflags, int devtype, struct thread *td) 347 { 348 struct cdevsw *dsw; 349 int ref, retval; 350 351 dsw = dev_refthread(dev, &ref); 352 if (dsw == NULL) 353 return (ENXIO); 354 mtx_lock(&Giant); 355 retval = dsw->d_gianttrick->d_open(dev, oflags, devtype, td); 356 mtx_unlock(&Giant); 357 dev_relthread(dev, ref); 358 return (retval); 359 } 360 361 static int 362 giant_fdopen(struct cdev *dev, int oflags, struct thread *td, struct file *fp) 363 { 364 struct cdevsw *dsw; 365 int ref, retval; 366 367 dsw = dev_refthread(dev, &ref); 368 if (dsw == NULL) 369 return (ENXIO); 370 mtx_lock(&Giant); 371 retval = dsw->d_gianttrick->d_fdopen(dev, oflags, td, fp); 372 mtx_unlock(&Giant); 373 dev_relthread(dev, ref); 374 return (retval); 375 } 376 377 static int 378 giant_close(struct cdev *dev, int fflag, int devtype, struct thread *td) 379 { 380 struct cdevsw *dsw; 381 int ref, retval; 382 383 dsw = dev_refthread(dev, &ref); 384 if (dsw == NULL) 385 return (ENXIO); 386 mtx_lock(&Giant); 387 retval = dsw->d_gianttrick->d_close(dev, fflag, devtype, td); 388 mtx_unlock(&Giant); 389 dev_relthread(dev, ref); 390 return (retval); 391 } 392 393 static void 394 giant_strategy(struct bio *bp) 395 { 396 struct cdevsw *dsw; 397 struct cdev *dev; 398 int ref; 399 400 dev = bp->bio_dev; 401 dsw = dev_refthread(dev, &ref); 402 if (dsw == NULL) { 403 biofinish(bp, NULL, ENXIO); 404 return; 405 } 406 mtx_lock(&Giant); 407 dsw->d_gianttrick->d_strategy(bp); 408 mtx_unlock(&Giant); 409 dev_relthread(dev, ref); 410 } 411 412 static int 413 giant_ioctl(struct cdev *dev, u_long cmd, caddr_t data, int fflag, struct thread *td) 414 { 415 struct cdevsw *dsw; 416 int ref, retval; 417 418 dsw = dev_refthread(dev, &ref); 419 if (dsw == NULL) 420 return (ENXIO); 421 mtx_lock(&Giant); 422 retval = dsw->d_gianttrick->d_ioctl(dev, cmd, data, fflag, td); 423 mtx_unlock(&Giant); 424 dev_relthread(dev, ref); 425 return (retval); 426 } 427 428 static int 429 giant_read(struct cdev *dev, struct uio *uio, int ioflag) 430 { 431 struct cdevsw *dsw; 432 int ref, retval; 433 434 dsw = dev_refthread(dev, &ref); 435 if (dsw == NULL) 436 return (ENXIO); 437 mtx_lock(&Giant); 438 retval = dsw->d_gianttrick->d_read(dev, uio, ioflag); 439 mtx_unlock(&Giant); 440 dev_relthread(dev, ref); 441 return (retval); 442 } 443 444 static int 445 giant_write(struct cdev *dev, struct uio *uio, int ioflag) 446 { 447 struct cdevsw *dsw; 448 int ref, retval; 449 450 dsw = dev_refthread(dev, &ref); 451 if (dsw == NULL) 452 return (ENXIO); 453 mtx_lock(&Giant); 454 retval = dsw->d_gianttrick->d_write(dev, uio, ioflag); 455 mtx_unlock(&Giant); 456 dev_relthread(dev, ref); 457 return (retval); 458 } 459 460 static int 461 giant_poll(struct cdev *dev, int events, struct thread *td) 462 { 463 struct cdevsw *dsw; 464 int ref, retval; 465 466 dsw = dev_refthread(dev, &ref); 467 if (dsw == NULL) 468 return (ENXIO); 469 mtx_lock(&Giant); 470 retval = dsw->d_gianttrick->d_poll(dev, events, td); 471 mtx_unlock(&Giant); 472 dev_relthread(dev, ref); 473 return (retval); 474 } 475 476 static int 477 giant_kqfilter(struct cdev *dev, struct knote *kn) 478 { 479 struct cdevsw *dsw; 480 int ref, retval; 481 482 dsw = dev_refthread(dev, &ref); 483 if (dsw == NULL) 484 return (ENXIO); 485 mtx_lock(&Giant); 486 retval = dsw->d_gianttrick->d_kqfilter(dev, kn); 487 mtx_unlock(&Giant); 488 dev_relthread(dev, ref); 489 return (retval); 490 } 491 492 static int 493 giant_mmap(struct cdev *dev, vm_ooffset_t offset, vm_paddr_t *paddr, int nprot, 494 vm_memattr_t *memattr) 495 { 496 struct cdevsw *dsw; 497 int ref, retval; 498 499 dsw = dev_refthread(dev, &ref); 500 if (dsw == NULL) 501 return (ENXIO); 502 mtx_lock(&Giant); 503 retval = dsw->d_gianttrick->d_mmap(dev, offset, paddr, nprot, 504 memattr); 505 mtx_unlock(&Giant); 506 dev_relthread(dev, ref); 507 return (retval); 508 } 509 510 static int 511 giant_mmap_single(struct cdev *dev, vm_ooffset_t *offset, vm_size_t size, 512 vm_object_t *object, int nprot) 513 { 514 struct cdevsw *dsw; 515 int ref, retval; 516 517 dsw = dev_refthread(dev, &ref); 518 if (dsw == NULL) 519 return (ENXIO); 520 mtx_lock(&Giant); 521 retval = dsw->d_gianttrick->d_mmap_single(dev, offset, size, object, 522 nprot); 523 mtx_unlock(&Giant); 524 dev_relthread(dev, ref); 525 return (retval); 526 } 527 528 static void 529 notify(struct cdev *dev, const char *ev, int flags) 530 { 531 static const char prefix[] = "cdev="; 532 char *data; 533 int namelen, mflags; 534 535 if (cold) 536 return; 537 mflags = (flags & MAKEDEV_NOWAIT) ? M_NOWAIT : M_WAITOK; 538 namelen = strlen(dev->si_name); 539 data = malloc(namelen + sizeof(prefix), M_TEMP, mflags); 540 if (data == NULL) 541 return; 542 memcpy(data, prefix, sizeof(prefix) - 1); 543 memcpy(data + sizeof(prefix) - 1, dev->si_name, namelen + 1); 544 devctl_notify("DEVFS", "CDEV", ev, data); 545 free(data, M_TEMP); 546 } 547 548 static void 549 notify_create(struct cdev *dev, int flags) 550 { 551 552 notify(dev, "CREATE", flags); 553 } 554 555 static void 556 notify_destroy(struct cdev *dev) 557 { 558 559 notify(dev, "DESTROY", MAKEDEV_WAITOK); 560 } 561 562 static struct cdev * 563 newdev(struct make_dev_args *args, struct cdev *si) 564 { 565 struct cdev *si2; 566 struct cdevsw *csw; 567 568 dev_lock_assert_locked(); 569 csw = args->mda_devsw; 570 si2 = NULL; 571 if (csw->d_flags & D_NEEDMINOR) { 572 /* We may want to return an existing device */ 573 LIST_FOREACH(si2, &csw->d_devs, si_list) { 574 if (dev2unit(si2) == args->mda_unit) { 575 dev_free_devlocked(si); 576 si = si2; 577 break; 578 } 579 } 580 581 /* 582 * If we're returning an existing device, we should make sure 583 * it isn't already initialized. This would have been caught 584 * in consumers anyways, but it's good to catch such a case 585 * early. We still need to complete initialization of the 586 * device, and we'll use whatever make_dev_args were passed in 587 * to do so. 588 */ 589 KASSERT(si2 == NULL || (si2->si_flags & SI_NAMED) == 0, 590 ("make_dev() by driver %s on pre-existing device (min=%x, name=%s)", 591 args->mda_devsw->d_name, dev2unit(si2), devtoname(si2))); 592 } 593 si->si_drv0 = args->mda_unit; 594 si->si_drv1 = args->mda_si_drv1; 595 si->si_drv2 = args->mda_si_drv2; 596 /* Only push to csw->d_devs if it's not a cloned device. */ 597 if (si2 == NULL) { 598 si->si_devsw = csw; 599 LIST_INSERT_HEAD(&csw->d_devs, si, si_list); 600 } else { 601 KASSERT(si->si_devsw == csw, 602 ("%s: inconsistent devsw between clone_create() and make_dev()", 603 __func__)); 604 } 605 return (si); 606 } 607 608 static void 609 fini_cdevsw(struct cdevsw *devsw) 610 { 611 struct cdevsw *gt; 612 613 if (devsw->d_gianttrick != NULL) { 614 gt = devsw->d_gianttrick; 615 memcpy(devsw, gt, sizeof *devsw); 616 cdevsw_free_devlocked(gt); 617 devsw->d_gianttrick = NULL; 618 } 619 devsw->d_flags &= ~D_INIT; 620 } 621 622 static int 623 prep_cdevsw(struct cdevsw *devsw, int flags) 624 { 625 struct cdevsw *dsw2; 626 627 dev_lock_assert_locked(); 628 if (devsw->d_flags & D_INIT) 629 return (0); 630 if (devsw->d_flags & D_NEEDGIANT) { 631 dev_unlock(); 632 dsw2 = malloc(sizeof *dsw2, M_DEVT, 633 (flags & MAKEDEV_NOWAIT) ? M_NOWAIT : M_WAITOK); 634 dev_lock(); 635 if (dsw2 == NULL && !(devsw->d_flags & D_INIT)) 636 return (ENOMEM); 637 } else 638 dsw2 = NULL; 639 if (devsw->d_flags & D_INIT) { 640 if (dsw2 != NULL) 641 cdevsw_free_devlocked(dsw2); 642 return (0); 643 } 644 645 if (devsw->d_version != D_VERSION_04) { 646 printf( 647 "WARNING: Device driver \"%s\" has wrong version %s\n", 648 devsw->d_name == NULL ? "???" : devsw->d_name, 649 "and is disabled. Recompile KLD module."); 650 devsw->d_open = dead_open; 651 devsw->d_close = dead_close; 652 devsw->d_read = dead_read; 653 devsw->d_write = dead_write; 654 devsw->d_ioctl = dead_ioctl; 655 devsw->d_poll = dead_poll; 656 devsw->d_mmap = dead_mmap; 657 devsw->d_mmap_single = dead_mmap_single; 658 devsw->d_strategy = dead_strategy; 659 devsw->d_kqfilter = dead_kqfilter; 660 } 661 662 if ((devsw->d_flags & D_NEEDGIANT) != 0) { 663 if ((devsw->d_flags & D_GIANTOK) == 0) { 664 printf( 665 "WARNING: Device \"%s\" is Giant locked and may be " 666 "deleted before FreeBSD 14.0.\n", 667 devsw->d_name == NULL ? "???" : devsw->d_name); 668 } 669 if (devsw->d_gianttrick == NULL) { 670 memcpy(dsw2, devsw, sizeof *dsw2); 671 devsw->d_gianttrick = dsw2; 672 dsw2 = NULL; 673 } 674 } 675 676 #define FIXUP(member, noop, giant) \ 677 do { \ 678 if (devsw->member == NULL) { \ 679 devsw->member = noop; \ 680 } else if (devsw->d_flags & D_NEEDGIANT) \ 681 devsw->member = giant; \ 682 } \ 683 while (0) 684 685 FIXUP(d_open, null_open, giant_open); 686 FIXUP(d_fdopen, NULL, giant_fdopen); 687 FIXUP(d_close, null_close, giant_close); 688 FIXUP(d_read, no_read, giant_read); 689 FIXUP(d_write, no_write, giant_write); 690 FIXUP(d_ioctl, no_ioctl, giant_ioctl); 691 FIXUP(d_poll, no_poll, giant_poll); 692 FIXUP(d_mmap, no_mmap, giant_mmap); 693 FIXUP(d_strategy, no_strategy, giant_strategy); 694 FIXUP(d_kqfilter, no_kqfilter, giant_kqfilter); 695 FIXUP(d_mmap_single, no_mmap_single, giant_mmap_single); 696 697 LIST_INIT(&devsw->d_devs); 698 699 devsw->d_flags |= D_INIT; 700 701 if (dsw2 != NULL) 702 cdevsw_free_devlocked(dsw2); 703 return (0); 704 } 705 706 static int 707 prep_devname(struct cdev *dev, const char *fmt, va_list ap) 708 { 709 int len; 710 char *from, *q, *s, *to; 711 712 dev_lock_assert_locked(); 713 714 len = vsnrprintf(dev->si_name, sizeof(dev->si_name), 32, fmt, ap); 715 if (len > sizeof(dev->si_name) - 1) 716 return (ENAMETOOLONG); 717 718 /* Strip leading slashes. */ 719 for (from = dev->si_name; *from == '/'; from++) 720 ; 721 722 for (to = dev->si_name; *from != '\0'; from++, to++) { 723 /* 724 * Spaces and double quotation marks cause 725 * problems for the devctl(4) protocol. 726 * Reject names containing those characters. 727 */ 728 if (isspace(*from) || *from == '"') 729 return (EINVAL); 730 /* Treat multiple sequential slashes as single. */ 731 while (from[0] == '/' && from[1] == '/') 732 from++; 733 /* Trailing slash is considered invalid. */ 734 if (from[0] == '/' && from[1] == '\0') 735 return (EINVAL); 736 *to = *from; 737 } 738 *to = '\0'; 739 740 if (dev->si_name[0] == '\0') 741 return (EINVAL); 742 743 /* Disallow "." and ".." components. */ 744 for (s = dev->si_name;;) { 745 for (q = s; *q != '/' && *q != '\0'; q++) 746 ; 747 if (q - s == 1 && s[0] == '.') 748 return (EINVAL); 749 if (q - s == 2 && s[0] == '.' && s[1] == '.') 750 return (EINVAL); 751 if (*q != '/') 752 break; 753 s = q + 1; 754 } 755 756 if (devfs_dev_exists(dev->si_name) != 0) 757 return (EEXIST); 758 759 return (0); 760 } 761 762 void 763 make_dev_args_init_impl(struct make_dev_args *args, size_t sz) 764 { 765 766 bzero(args, sz); 767 args->mda_size = sz; 768 } 769 770 static int 771 make_dev_sv(struct make_dev_args *args1, struct cdev **dres, 772 const char *fmt, va_list ap) 773 { 774 struct cdev *dev, *dev_new; 775 struct make_dev_args args; 776 int res; 777 778 bzero(&args, sizeof(args)); 779 if (sizeof(args) < args1->mda_size) 780 return (EINVAL); 781 bcopy(args1, &args, args1->mda_size); 782 KASSERT((args.mda_flags & MAKEDEV_WAITOK) == 0 || 783 (args.mda_flags & MAKEDEV_NOWAIT) == 0, 784 ("make_dev_sv: both WAITOK and NOWAIT specified")); 785 dev_new = devfs_alloc(args.mda_flags); 786 if (dev_new == NULL) 787 return (ENOMEM); 788 dev_lock(); 789 res = prep_cdevsw(args.mda_devsw, args.mda_flags); 790 if (res != 0) { 791 dev_unlock(); 792 devfs_free(dev_new); 793 return (res); 794 } 795 dev = newdev(&args, dev_new); 796 if ((dev->si_flags & SI_NAMED) == 0) { 797 res = prep_devname(dev, fmt, ap); 798 if (res != 0) { 799 if ((args.mda_flags & MAKEDEV_CHECKNAME) == 0) { 800 panic( 801 "make_dev_sv: bad si_name (error=%d, si_name=%s)", 802 res, dev->si_name); 803 } 804 if (dev == dev_new) { 805 LIST_REMOVE(dev, si_list); 806 dev_unlock(); 807 devfs_free(dev); 808 } else 809 dev_unlock(); 810 return (res); 811 } 812 } 813 if ((args.mda_flags & MAKEDEV_REF) != 0) 814 dev_refl(dev); 815 if ((args.mda_flags & MAKEDEV_ETERNAL) != 0) 816 dev->si_flags |= SI_ETERNAL; 817 KASSERT(!(dev->si_flags & SI_NAMED), 818 ("make_dev() by driver %s on pre-existing device (min=%x, name=%s)", 819 args.mda_devsw->d_name, dev2unit(dev), devtoname(dev))); 820 dev->si_flags |= SI_NAMED; 821 if (args.mda_cr != NULL) 822 dev->si_cred = crhold(args.mda_cr); 823 dev->si_uid = args.mda_uid; 824 dev->si_gid = args.mda_gid; 825 dev->si_mode = args.mda_mode; 826 827 devfs_create(dev); 828 clean_unrhdrl(devfs_inos); 829 dev_unlock_and_free(); 830 831 notify_create(dev, args.mda_flags); 832 833 *dres = dev; 834 return (0); 835 } 836 837 int 838 make_dev_s(struct make_dev_args *args, struct cdev **dres, 839 const char *fmt, ...) 840 { 841 va_list ap; 842 int res; 843 844 va_start(ap, fmt); 845 res = make_dev_sv(args, dres, fmt, ap); 846 va_end(ap); 847 return (res); 848 } 849 850 static int 851 make_dev_credv(int flags, struct cdev **dres, struct cdevsw *devsw, int unit, 852 struct ucred *cr, uid_t uid, gid_t gid, int mode, const char *fmt, 853 va_list ap) 854 { 855 struct make_dev_args args; 856 857 make_dev_args_init(&args); 858 args.mda_flags = flags; 859 args.mda_devsw = devsw; 860 args.mda_cr = cr; 861 args.mda_uid = uid; 862 args.mda_gid = gid; 863 args.mda_mode = mode; 864 args.mda_unit = unit; 865 return (make_dev_sv(&args, dres, fmt, ap)); 866 } 867 868 struct cdev * 869 make_dev(struct cdevsw *devsw, int unit, uid_t uid, gid_t gid, int mode, 870 const char *fmt, ...) 871 { 872 struct cdev *dev; 873 va_list ap; 874 int res __unused; 875 876 va_start(ap, fmt); 877 res = make_dev_credv(0, &dev, devsw, unit, NULL, uid, gid, mode, fmt, 878 ap); 879 va_end(ap); 880 KASSERT(res == 0 && dev != NULL, 881 ("make_dev: failed make_dev_credv (error=%d)", res)); 882 return (dev); 883 } 884 885 struct cdev * 886 make_dev_cred(struct cdevsw *devsw, int unit, struct ucred *cr, uid_t uid, 887 gid_t gid, int mode, const char *fmt, ...) 888 { 889 struct cdev *dev; 890 va_list ap; 891 int res __unused; 892 893 va_start(ap, fmt); 894 res = make_dev_credv(0, &dev, devsw, unit, cr, uid, gid, mode, fmt, ap); 895 va_end(ap); 896 897 KASSERT(res == 0 && dev != NULL, 898 ("make_dev_cred: failed make_dev_credv (error=%d)", res)); 899 return (dev); 900 } 901 902 struct cdev * 903 make_dev_credf(int flags, struct cdevsw *devsw, int unit, struct ucred *cr, 904 uid_t uid, gid_t gid, int mode, const char *fmt, ...) 905 { 906 struct cdev *dev; 907 va_list ap; 908 int res; 909 910 va_start(ap, fmt); 911 res = make_dev_credv(flags, &dev, devsw, unit, cr, uid, gid, mode, 912 fmt, ap); 913 va_end(ap); 914 915 KASSERT(((flags & MAKEDEV_NOWAIT) != 0 && res == ENOMEM) || 916 ((flags & MAKEDEV_CHECKNAME) != 0 && res != ENOMEM) || res == 0, 917 ("make_dev_credf: failed make_dev_credv (error=%d)", res)); 918 return (res == 0 ? dev : NULL); 919 } 920 921 int 922 make_dev_p(int flags, struct cdev **cdev, struct cdevsw *devsw, 923 struct ucred *cr, uid_t uid, gid_t gid, int mode, const char *fmt, ...) 924 { 925 va_list ap; 926 int res; 927 928 va_start(ap, fmt); 929 res = make_dev_credv(flags, cdev, devsw, 0, cr, uid, gid, mode, 930 fmt, ap); 931 va_end(ap); 932 933 KASSERT(((flags & MAKEDEV_NOWAIT) != 0 && res == ENOMEM) || 934 ((flags & MAKEDEV_CHECKNAME) != 0 && res != ENOMEM) || res == 0, 935 ("make_dev_p: failed make_dev_credv (error=%d)", res)); 936 return (res); 937 } 938 939 static void 940 dev_dependsl(struct cdev *pdev, struct cdev *cdev) 941 { 942 943 cdev->si_parent = pdev; 944 cdev->si_flags |= SI_CHILD; 945 LIST_INSERT_HEAD(&pdev->si_children, cdev, si_siblings); 946 } 947 948 void 949 dev_depends(struct cdev *pdev, struct cdev *cdev) 950 { 951 952 dev_lock(); 953 dev_dependsl(pdev, cdev); 954 dev_unlock(); 955 } 956 957 static int 958 make_dev_alias_v(int flags, struct cdev **cdev, struct cdev *pdev, 959 const char *fmt, va_list ap) 960 { 961 struct cdev *dev; 962 int error; 963 964 KASSERT(pdev != NULL, ("make_dev_alias_v: pdev is NULL")); 965 KASSERT((flags & MAKEDEV_WAITOK) == 0 || (flags & MAKEDEV_NOWAIT) == 0, 966 ("make_dev_alias_v: both WAITOK and NOWAIT specified")); 967 KASSERT((flags & ~(MAKEDEV_WAITOK | MAKEDEV_NOWAIT | 968 MAKEDEV_CHECKNAME)) == 0, 969 ("make_dev_alias_v: invalid flags specified (flags=%02x)", flags)); 970 971 dev = devfs_alloc(flags); 972 if (dev == NULL) 973 return (ENOMEM); 974 dev_lock(); 975 dev->si_flags |= SI_ALIAS; 976 error = prep_devname(dev, fmt, ap); 977 if (error != 0) { 978 if ((flags & MAKEDEV_CHECKNAME) == 0) { 979 panic("make_dev_alias_v: bad si_name " 980 "(error=%d, si_name=%s)", error, dev->si_name); 981 } 982 dev_unlock(); 983 devfs_free(dev); 984 return (error); 985 } 986 dev->si_flags |= SI_NAMED; 987 devfs_create(dev); 988 dev_dependsl(pdev, dev); 989 clean_unrhdrl(devfs_inos); 990 dev_unlock(); 991 992 notify_create(dev, flags); 993 *cdev = dev; 994 995 return (0); 996 } 997 998 struct cdev * 999 make_dev_alias(struct cdev *pdev, const char *fmt, ...) 1000 { 1001 struct cdev *dev; 1002 va_list ap; 1003 int res __unused; 1004 1005 va_start(ap, fmt); 1006 res = make_dev_alias_v(MAKEDEV_WAITOK, &dev, pdev, fmt, ap); 1007 va_end(ap); 1008 1009 KASSERT(res == 0 && dev != NULL, 1010 ("make_dev_alias: failed make_dev_alias_v (error=%d)", res)); 1011 return (dev); 1012 } 1013 1014 int 1015 make_dev_alias_p(int flags, struct cdev **cdev, struct cdev *pdev, 1016 const char *fmt, ...) 1017 { 1018 va_list ap; 1019 int res; 1020 1021 va_start(ap, fmt); 1022 res = make_dev_alias_v(flags, cdev, pdev, fmt, ap); 1023 va_end(ap); 1024 return (res); 1025 } 1026 1027 int 1028 make_dev_physpath_alias(int flags, struct cdev **cdev, struct cdev *pdev, 1029 struct cdev *old_alias, const char *physpath) 1030 { 1031 char *devfspath; 1032 int physpath_len; 1033 int max_parentpath_len; 1034 int parentpath_len; 1035 int devfspathbuf_len; 1036 int mflags; 1037 int ret; 1038 1039 *cdev = NULL; 1040 devfspath = NULL; 1041 physpath_len = strlen(physpath); 1042 ret = EINVAL; 1043 if (physpath_len == 0) 1044 goto out; 1045 1046 if (strncmp("id1,", physpath, 4) == 0) { 1047 physpath += 4; 1048 physpath_len -= 4; 1049 if (physpath_len == 0) 1050 goto out; 1051 } 1052 1053 max_parentpath_len = SPECNAMELEN - physpath_len - /*/*/1; 1054 parentpath_len = strlen(pdev->si_name); 1055 if (max_parentpath_len < parentpath_len) { 1056 if (bootverbose) 1057 printf("WARNING: Unable to alias %s " 1058 "to %s/%s - path too long\n", 1059 pdev->si_name, physpath, pdev->si_name); 1060 ret = ENAMETOOLONG; 1061 goto out; 1062 } 1063 1064 mflags = (flags & MAKEDEV_NOWAIT) ? M_NOWAIT : M_WAITOK; 1065 devfspathbuf_len = physpath_len + /*/*/1 + parentpath_len + /*NUL*/1; 1066 devfspath = malloc(devfspathbuf_len, M_DEVBUF, mflags); 1067 if (devfspath == NULL) { 1068 ret = ENOMEM; 1069 goto out; 1070 } 1071 1072 sprintf(devfspath, "%s/%s", physpath, pdev->si_name); 1073 if (old_alias != NULL && strcmp(old_alias->si_name, devfspath) == 0) { 1074 /* Retain the existing alias. */ 1075 *cdev = old_alias; 1076 old_alias = NULL; 1077 ret = 0; 1078 } else { 1079 ret = make_dev_alias_p(flags, cdev, pdev, "%s", devfspath); 1080 } 1081 out: 1082 if (old_alias != NULL) 1083 destroy_dev(old_alias); 1084 if (devfspath != NULL) 1085 free(devfspath, M_DEVBUF); 1086 return (ret); 1087 } 1088 1089 static void 1090 destroy_devl(struct cdev *dev) 1091 { 1092 struct cdevsw *csw; 1093 struct cdev_privdata *p; 1094 struct cdev_priv *cdp; 1095 1096 dev_lock_assert_locked(); 1097 KASSERT(dev->si_flags & SI_NAMED, 1098 ("WARNING: Driver mistake: destroy_dev on %d\n", dev2unit(dev))); 1099 KASSERT((dev->si_flags & SI_ETERNAL) == 0, 1100 ("WARNING: Driver mistake: destroy_dev on eternal %d\n", 1101 dev2unit(dev))); 1102 1103 cdp = cdev2priv(dev); 1104 if ((cdp->cdp_flags & CDP_UNREF_DTR) == 0) { 1105 /* 1106 * Avoid race with dev_rel(), e.g. from the populate 1107 * loop. If CDP_UNREF_DTR flag is set, the reference 1108 * to be dropped at the end of destroy_devl() was 1109 * already taken by delist_dev_locked(). 1110 */ 1111 dev_refl(dev); 1112 1113 devfs_destroy(dev); 1114 } 1115 1116 /* Remove name marking */ 1117 dev->si_flags &= ~SI_NAMED; 1118 1119 /* If we are a child, remove us from the parents list */ 1120 if (dev->si_flags & SI_CHILD) { 1121 LIST_REMOVE(dev, si_siblings); 1122 dev->si_flags &= ~SI_CHILD; 1123 } 1124 1125 /* Kill our children */ 1126 while (!LIST_EMPTY(&dev->si_children)) 1127 destroy_devl(LIST_FIRST(&dev->si_children)); 1128 1129 /* Remove from clone list */ 1130 if (dev->si_flags & SI_CLONELIST) { 1131 LIST_REMOVE(dev, si_clone); 1132 dev->si_flags &= ~SI_CLONELIST; 1133 } 1134 1135 mtx_lock(&cdp->cdp_threadlock); 1136 csw = dev->si_devsw; 1137 dev->si_devsw = NULL; /* already NULL for SI_ALIAS */ 1138 while (csw != NULL && csw->d_purge != NULL && dev->si_threadcount) { 1139 csw->d_purge(dev); 1140 mtx_unlock(&cdp->cdp_threadlock); 1141 msleep(csw, &devmtx, PRIBIO, "devprg", hz/10); 1142 mtx_lock(&cdp->cdp_threadlock); 1143 if (dev->si_threadcount) 1144 printf("Still %lu threads in %s\n", 1145 dev->si_threadcount, devtoname(dev)); 1146 } 1147 while (dev->si_threadcount != 0) { 1148 /* Use unique dummy wait ident */ 1149 mtx_unlock(&cdp->cdp_threadlock); 1150 msleep(&csw, &devmtx, PRIBIO, "devdrn", hz / 10); 1151 mtx_lock(&cdp->cdp_threadlock); 1152 } 1153 1154 mtx_unlock(&cdp->cdp_threadlock); 1155 dev_unlock(); 1156 if ((cdp->cdp_flags & CDP_UNREF_DTR) == 0) { 1157 /* avoid out of order notify events */ 1158 notify_destroy(dev); 1159 } 1160 mtx_lock(&cdevpriv_mtx); 1161 while ((p = LIST_FIRST(&cdp->cdp_fdpriv)) != NULL) { 1162 devfs_destroy_cdevpriv(p); 1163 mtx_lock(&cdevpriv_mtx); 1164 } 1165 mtx_unlock(&cdevpriv_mtx); 1166 dev_lock(); 1167 1168 dev->si_drv1 = 0; 1169 dev->si_drv2 = 0; 1170 1171 if (!(dev->si_flags & SI_ALIAS)) { 1172 /* Remove from cdevsw list */ 1173 LIST_REMOVE(dev, si_list); 1174 1175 /* If cdevsw has no more struct cdev *'s, clean it */ 1176 if (LIST_EMPTY(&csw->d_devs)) { 1177 fini_cdevsw(csw); 1178 wakeup(&csw->d_devs); 1179 } 1180 } 1181 dev->si_flags &= ~SI_ALIAS; 1182 cdp->cdp_flags &= ~CDP_UNREF_DTR; 1183 dev->si_refcount--; 1184 1185 if (dev->si_refcount > 0) 1186 LIST_INSERT_HEAD(&dead_cdevsw.d_devs, dev, si_list); 1187 else 1188 dev_free_devlocked(dev); 1189 } 1190 1191 static void 1192 delist_dev_locked(struct cdev *dev) 1193 { 1194 struct cdev_priv *cdp; 1195 struct cdev *child; 1196 1197 dev_lock_assert_locked(); 1198 cdp = cdev2priv(dev); 1199 if ((cdp->cdp_flags & CDP_UNREF_DTR) != 0) 1200 return; 1201 cdp->cdp_flags |= CDP_UNREF_DTR; 1202 dev_refl(dev); 1203 devfs_destroy(dev); 1204 LIST_FOREACH(child, &dev->si_children, si_siblings) 1205 delist_dev_locked(child); 1206 dev_unlock(); 1207 /* ensure the destroy event is queued in order */ 1208 notify_destroy(dev); 1209 dev_lock(); 1210 } 1211 1212 /* 1213 * This function will delist a character device and its children from 1214 * the directory listing and create a destroy event without waiting 1215 * for all character device references to go away. At some later point 1216 * destroy_dev() must be called to complete the character device 1217 * destruction. After calling this function the character device name 1218 * can instantly be re-used. 1219 */ 1220 void 1221 delist_dev(struct cdev *dev) 1222 { 1223 1224 WITNESS_WARN(WARN_GIANTOK | WARN_SLEEPOK, NULL, "delist_dev"); 1225 dev_lock(); 1226 delist_dev_locked(dev); 1227 dev_unlock(); 1228 } 1229 1230 void 1231 destroy_dev(struct cdev *dev) 1232 { 1233 1234 WITNESS_WARN(WARN_GIANTOK | WARN_SLEEPOK, NULL, "destroy_dev"); 1235 dev_lock(); 1236 destroy_devl(dev); 1237 dev_unlock_and_free(); 1238 } 1239 1240 const char * 1241 devtoname(struct cdev *dev) 1242 { 1243 1244 return (dev->si_name); 1245 } 1246 1247 int 1248 dev_stdclone(char *name, char **namep, const char *stem, int *unit) 1249 { 1250 int u, i; 1251 1252 i = strlen(stem); 1253 if (strncmp(stem, name, i) != 0) 1254 return (0); 1255 if (!isdigit(name[i])) 1256 return (0); 1257 u = 0; 1258 if (name[i] == '0' && isdigit(name[i+1])) 1259 return (0); 1260 while (isdigit(name[i])) { 1261 u *= 10; 1262 u += name[i++] - '0'; 1263 } 1264 if (u > 0xffffff) 1265 return (0); 1266 *unit = u; 1267 if (namep) 1268 *namep = &name[i]; 1269 if (name[i]) 1270 return (2); 1271 return (1); 1272 } 1273 1274 /* 1275 * Helper functions for cloning device drivers. 1276 * 1277 * The objective here is to make it unnecessary for the device drivers to 1278 * use rman or similar to manage their unit number space. Due to the way 1279 * we do "on-demand" devices, using rman or other "private" methods 1280 * will be very tricky to lock down properly once we lock down this file. 1281 * 1282 * Instead we give the drivers these routines which puts the struct cdev *'s 1283 * that are to be managed on their own list, and gives the driver the ability 1284 * to ask for the first free unit number or a given specified unit number. 1285 * 1286 * In addition these routines support paired devices (pty, nmdm and similar) 1287 * by respecting a number of "flag" bits in the minor number. 1288 * 1289 */ 1290 1291 struct clonedevs { 1292 LIST_HEAD(,cdev) head; 1293 }; 1294 1295 void 1296 clone_setup(struct clonedevs **cdp) 1297 { 1298 1299 *cdp = malloc(sizeof **cdp, M_DEVBUF, M_WAITOK | M_ZERO); 1300 LIST_INIT(&(*cdp)->head); 1301 } 1302 1303 int 1304 clone_create(struct clonedevs **cdp, struct cdevsw *csw, int *up, 1305 struct cdev **dp, int extra) 1306 { 1307 struct clonedevs *cd; 1308 struct cdev *dev, *ndev, *dl, *de; 1309 struct make_dev_args args; 1310 int unit, low, u; 1311 1312 KASSERT(*cdp != NULL, 1313 ("clone_setup() not called in driver \"%s\"", csw->d_name)); 1314 KASSERT(!(extra & CLONE_UNITMASK), 1315 ("Illegal extra bits (0x%x) in clone_create", extra)); 1316 KASSERT(*up <= CLONE_UNITMASK, 1317 ("Too high unit (0x%x) in clone_create", *up)); 1318 KASSERT(csw->d_flags & D_NEEDMINOR, 1319 ("clone_create() on cdevsw without minor numbers")); 1320 1321 /* 1322 * Search the list for a lot of things in one go: 1323 * A preexisting match is returned immediately. 1324 * The lowest free unit number if we are passed -1, and the place 1325 * in the list where we should insert that new element. 1326 * The place to insert a specified unit number, if applicable 1327 * the end of the list. 1328 */ 1329 unit = *up; 1330 ndev = devfs_alloc(MAKEDEV_WAITOK); 1331 dev_lock(); 1332 prep_cdevsw(csw, MAKEDEV_WAITOK); 1333 low = extra; 1334 de = dl = NULL; 1335 cd = *cdp; 1336 LIST_FOREACH(dev, &cd->head, si_clone) { 1337 KASSERT(dev->si_flags & SI_CLONELIST, 1338 ("Dev %p(%s) should be on clonelist", dev, dev->si_name)); 1339 u = dev2unit(dev); 1340 if (u == (unit | extra)) { 1341 *dp = dev; 1342 dev_unlock(); 1343 devfs_free(ndev); 1344 return (0); 1345 } 1346 if (unit == -1 && u == low) { 1347 low++; 1348 de = dev; 1349 continue; 1350 } else if (u < (unit | extra)) { 1351 de = dev; 1352 continue; 1353 } else if (u > (unit | extra)) { 1354 dl = dev; 1355 break; 1356 } 1357 } 1358 if (unit == -1) 1359 unit = low & CLONE_UNITMASK; 1360 make_dev_args_init(&args); 1361 args.mda_unit = unit | extra; 1362 args.mda_devsw = csw; 1363 dev = newdev(&args, ndev); 1364 if (dev->si_flags & SI_CLONELIST) { 1365 printf("dev %p (%s) is on clonelist\n", dev, dev->si_name); 1366 printf("unit=%d, low=%d, extra=0x%x\n", unit, low, extra); 1367 LIST_FOREACH(dev, &cd->head, si_clone) { 1368 printf("\t%p %s\n", dev, dev->si_name); 1369 } 1370 panic("foo"); 1371 } 1372 KASSERT(!(dev->si_flags & SI_CLONELIST), 1373 ("Dev %p(%s) should not be on clonelist", dev, dev->si_name)); 1374 if (dl != NULL) 1375 LIST_INSERT_BEFORE(dl, dev, si_clone); 1376 else if (de != NULL) 1377 LIST_INSERT_AFTER(de, dev, si_clone); 1378 else 1379 LIST_INSERT_HEAD(&cd->head, dev, si_clone); 1380 dev->si_flags |= SI_CLONELIST; 1381 *up = unit; 1382 dev_unlock_and_free(); 1383 return (1); 1384 } 1385 1386 /* 1387 * Kill everything still on the list. The driver should already have 1388 * disposed of any softc hung of the struct cdev *'s at this time. 1389 */ 1390 void 1391 clone_cleanup(struct clonedevs **cdp) 1392 { 1393 struct cdev *dev; 1394 struct cdev_priv *cp; 1395 struct clonedevs *cd; 1396 1397 cd = *cdp; 1398 if (cd == NULL) 1399 return; 1400 dev_lock(); 1401 while (!LIST_EMPTY(&cd->head)) { 1402 dev = LIST_FIRST(&cd->head); 1403 LIST_REMOVE(dev, si_clone); 1404 KASSERT(dev->si_flags & SI_CLONELIST, 1405 ("Dev %p(%s) should be on clonelist", dev, dev->si_name)); 1406 dev->si_flags &= ~SI_CLONELIST; 1407 cp = cdev2priv(dev); 1408 if (!(cp->cdp_flags & CDP_SCHED_DTR)) { 1409 cp->cdp_flags |= CDP_SCHED_DTR; 1410 KASSERT(dev->si_flags & SI_NAMED, 1411 ("Driver has goofed in cloning underways udev %jx unit %x", 1412 (uintmax_t)dev2udev(dev), dev2unit(dev))); 1413 destroy_devl(dev); 1414 } 1415 } 1416 dev_unlock_and_free(); 1417 free(cd, M_DEVBUF); 1418 *cdp = NULL; 1419 } 1420 1421 static TAILQ_HEAD(, cdev_priv) dev_ddtr = 1422 TAILQ_HEAD_INITIALIZER(dev_ddtr); 1423 static TAILQ_HEAD(, cdev_priv) dev_ddtr_giant = 1424 TAILQ_HEAD_INITIALIZER(dev_ddtr_giant); 1425 static struct task dev_dtr_task = TASK_INITIALIZER(0, destroy_dev_tq, &dev_ddtr); 1426 static struct task dev_dtr_task_giant = TASK_INITIALIZER(0, destroy_dev_tq_giant, 1427 &dev_ddtr_giant); 1428 1429 static void 1430 destroy_dev_tq(void *ctx, int pending) 1431 { 1432 TAILQ_HEAD(, cdev_priv) *ddtr = ctx; 1433 struct cdev_priv *cp; 1434 struct cdev *dev; 1435 void (*cb)(void *); 1436 void *cb_arg; 1437 1438 dev_lock(); 1439 while (!TAILQ_EMPTY(ddtr)) { 1440 cp = TAILQ_FIRST(ddtr); 1441 dev = &cp->cdp_c; 1442 KASSERT(cp->cdp_flags & CDP_SCHED_DTR, 1443 ("cdev %p in dev_destroy_tq without CDP_SCHED_DTR", cp)); 1444 TAILQ_REMOVE(ddtr, cp, cdp_dtr_list); 1445 cb = cp->cdp_dtr_cb; 1446 cb_arg = cp->cdp_dtr_cb_arg; 1447 destroy_devl(dev); 1448 dev_unlock_and_free(); 1449 dev_rel(dev); 1450 if (cb != NULL) 1451 cb(cb_arg); 1452 dev_lock(); 1453 } 1454 dev_unlock(); 1455 } 1456 1457 static void 1458 destroy_dev_tq_giant(void *ctx, int pending) 1459 { 1460 mtx_lock(&Giant); 1461 destroy_dev_tq(ctx, pending); 1462 mtx_unlock(&Giant); 1463 } 1464 1465 /* 1466 * devmtx shall be locked on entry. devmtx will be unlocked after 1467 * function return. 1468 */ 1469 static int 1470 destroy_dev_sched_cbl(struct cdev *dev, void (*cb)(void *), void *arg) 1471 { 1472 struct cdev_priv *cp; 1473 bool need_giant; 1474 1475 dev_lock_assert_locked(); 1476 cp = cdev2priv(dev); 1477 if (cp->cdp_flags & CDP_SCHED_DTR) { 1478 dev_unlock(); 1479 return (0); 1480 } 1481 dev_refl(dev); 1482 cp->cdp_flags |= CDP_SCHED_DTR; 1483 cp->cdp_dtr_cb = cb; 1484 cp->cdp_dtr_cb_arg = arg; 1485 need_giant = (dev->si_devsw->d_flags & D_NEEDGIANT) != 0; 1486 if (need_giant) 1487 TAILQ_INSERT_TAIL(&dev_ddtr_giant, cp, cdp_dtr_list); 1488 else 1489 TAILQ_INSERT_TAIL(&dev_ddtr, cp, cdp_dtr_list); 1490 dev_unlock(); 1491 if (need_giant) 1492 taskqueue_enqueue(taskqueue_thread, &dev_dtr_task_giant); 1493 else 1494 taskqueue_enqueue(taskqueue_thread, &dev_dtr_task); 1495 return (1); 1496 } 1497 1498 int 1499 destroy_dev_sched_cb(struct cdev *dev, void (*cb)(void *), void *arg) 1500 { 1501 1502 dev_lock(); 1503 return (destroy_dev_sched_cbl(dev, cb, arg)); 1504 } 1505 1506 int 1507 destroy_dev_sched(struct cdev *dev) 1508 { 1509 1510 return (destroy_dev_sched_cb(dev, NULL, NULL)); 1511 } 1512 1513 void 1514 destroy_dev_drain(struct cdevsw *csw) 1515 { 1516 1517 dev_lock(); 1518 while (!LIST_EMPTY(&csw->d_devs)) { 1519 msleep(&csw->d_devs, &devmtx, PRIBIO, "devscd", hz/10); 1520 } 1521 dev_unlock(); 1522 } 1523 1524 #include "opt_ddb.h" 1525 #ifdef DDB 1526 #include <sys/kernel.h> 1527 1528 #include <ddb/ddb.h> 1529 1530 DB_SHOW_COMMAND(cdev, db_show_cdev) 1531 { 1532 struct cdev_priv *cdp; 1533 struct cdev *dev; 1534 u_int flags; 1535 char buf[512]; 1536 1537 if (!have_addr) { 1538 TAILQ_FOREACH(cdp, &cdevp_list, cdp_list) { 1539 dev = &cdp->cdp_c; 1540 db_printf("%s %p\n", dev->si_name, dev); 1541 if (db_pager_quit) 1542 break; 1543 } 1544 return; 1545 } 1546 1547 dev = (struct cdev *)addr; 1548 cdp = cdev2priv(dev); 1549 db_printf("dev %s ref %d use %ld thr %ld inuse %u fdpriv %p\n", 1550 dev->si_name, dev->si_refcount, dev->si_usecount, 1551 dev->si_threadcount, cdp->cdp_inuse, cdp->cdp_fdpriv.lh_first); 1552 db_printf("devsw %p si_drv0 %d si_drv1 %p si_drv2 %p\n", 1553 dev->si_devsw, dev->si_drv0, dev->si_drv1, dev->si_drv2); 1554 flags = dev->si_flags; 1555 #define SI_FLAG(flag) do { \ 1556 if (flags & (flag)) { \ 1557 if (buf[0] != '\0') \ 1558 strlcat(buf, ", ", sizeof(buf)); \ 1559 strlcat(buf, (#flag) + 3, sizeof(buf)); \ 1560 flags &= ~(flag); \ 1561 } \ 1562 } while (0) 1563 buf[0] = '\0'; 1564 SI_FLAG(SI_ETERNAL); 1565 SI_FLAG(SI_ALIAS); 1566 SI_FLAG(SI_NAMED); 1567 SI_FLAG(SI_CHILD); 1568 SI_FLAG(SI_DUMPDEV); 1569 SI_FLAG(SI_CLONELIST); 1570 db_printf("si_flags %s\n", buf); 1571 1572 flags = cdp->cdp_flags; 1573 #define CDP_FLAG(flag) do { \ 1574 if (flags & (flag)) { \ 1575 if (buf[0] != '\0') \ 1576 strlcat(buf, ", ", sizeof(buf)); \ 1577 strlcat(buf, (#flag) + 4, sizeof(buf)); \ 1578 flags &= ~(flag); \ 1579 } \ 1580 } while (0) 1581 buf[0] = '\0'; 1582 CDP_FLAG(CDP_ACTIVE); 1583 CDP_FLAG(CDP_SCHED_DTR); 1584 db_printf("cdp_flags %s\n", buf); 1585 } 1586 #endif 1587