1/*- 2 * Copyright (c) 1999-2002 Poul-Henning Kamp 3 * All rights reserved. 4 * 5 * Redistribution and use in source and binary forms, with or without 6 * modification, are permitted provided that the following conditions 7 * are met: 8 * 1. Redistributions of source code must retain the above copyright 9 * notice, this list of conditions and the following disclaimer. 10 * 2. Redistributions in binary form must reproduce the above copyright 11 * notice, this list of conditions and the following disclaimer in the 12 * documentation and/or other materials provided with the distribution. 13 * 14 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 15 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 16 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 17 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 18 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 19 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 20 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 21 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 22 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 23 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 24 * SUCH DAMAGE. 25 */ 26 27#include <sys/cdefs.h> 28__FBSDID("$FreeBSD: stable/11/sys/kern/kern_conf.c 353783 2019-10-20 22:01:35Z kevans $"); 29 30#include <sys/param.h> 31#include <sys/kernel.h> 32#include <sys/systm.h> 33#include <sys/bus.h> 34#include <sys/bio.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 52static MALLOC_DEFINE(M_DEVT, "cdev", "cdev storage"); 53 54struct mtx devmtx; 55static void destroy_devl(struct cdev *dev); 56static int destroy_dev_sched_cbl(struct cdev *dev, 57 void (*cb)(void *), void *arg); 58static void destroy_dev_tq(void *ctx, int pending); 59static int make_dev_credv(int flags, struct cdev **dres, struct cdevsw *devsw, 60 int unit, struct ucred *cr, uid_t uid, gid_t gid, int mode, const char *fmt, 61 va_list ap); 62 63static struct cdev_priv_list cdevp_free_list = 64 TAILQ_HEAD_INITIALIZER(cdevp_free_list); 65static SLIST_HEAD(free_cdevsw, cdevsw) cdevsw_gt_post_list = 66 SLIST_HEAD_INITIALIZER(cdevsw_gt_post_list); 67 68void 69dev_lock(void) 70{ 71 72 mtx_lock(&devmtx); 73} 74 75/* 76 * Free all the memory collected while the cdev mutex was 77 * locked. Since devmtx is after the system map mutex, free() cannot 78 * be called immediately and is postponed until cdev mutex can be 79 * dropped. 80 */ 81static void 82dev_unlock_and_free(void) 83{ 84 struct cdev_priv_list cdp_free; 85 struct free_cdevsw csw_free; 86 struct cdev_priv *cdp; 87 struct cdevsw *csw; 88 89 mtx_assert(&devmtx, MA_OWNED); 90 91 /* 92 * Make the local copy of the list heads while the dev_mtx is 93 * held. Free it later. 94 */ 95 TAILQ_INIT(&cdp_free); 96 TAILQ_CONCAT(&cdp_free, &cdevp_free_list, cdp_list); 97 csw_free = cdevsw_gt_post_list; 98 SLIST_INIT(&cdevsw_gt_post_list); 99 100 mtx_unlock(&devmtx); 101 102 while ((cdp = TAILQ_FIRST(&cdp_free)) != NULL) { 103 TAILQ_REMOVE(&cdp_free, cdp, cdp_list); 104 devfs_free(&cdp->cdp_c); 105 } 106 while ((csw = SLIST_FIRST(&csw_free)) != NULL) { 107 SLIST_REMOVE_HEAD(&csw_free, d_postfree_list); 108 free(csw, M_DEVT); 109 } 110} 111 112static void 113dev_free_devlocked(struct cdev *cdev) 114{ 115 struct cdev_priv *cdp; 116 117 mtx_assert(&devmtx, MA_OWNED); 118 cdp = cdev2priv(cdev); 119 KASSERT((cdp->cdp_flags & CDP_UNREF_DTR) == 0, 120 ("destroy_dev() was not called after delist_dev(%p)", cdev)); 121 TAILQ_INSERT_HEAD(&cdevp_free_list, cdp, cdp_list); 122} 123 124static void 125cdevsw_free_devlocked(struct cdevsw *csw) 126{ 127 128 mtx_assert(&devmtx, MA_OWNED); 129 SLIST_INSERT_HEAD(&cdevsw_gt_post_list, csw, d_postfree_list); 130} 131 132void 133dev_unlock(void) 134{ 135 136 mtx_unlock(&devmtx); 137} 138 139void 140dev_ref(struct cdev *dev) 141{ 142 143 mtx_assert(&devmtx, MA_NOTOWNED); 144 mtx_lock(&devmtx); 145 dev->si_refcount++; 146 mtx_unlock(&devmtx); 147} 148 149void 150dev_refl(struct cdev *dev) 151{ 152 153 mtx_assert(&devmtx, MA_OWNED); 154 dev->si_refcount++; 155} 156 157void 158dev_rel(struct cdev *dev) 159{ 160 int flag = 0; 161 162 mtx_assert(&devmtx, MA_NOTOWNED); 163 dev_lock(); 164 dev->si_refcount--; 165 KASSERT(dev->si_refcount >= 0, 166 ("dev_rel(%s) gave negative count", devtoname(dev))); 167 if (dev->si_devsw == NULL && dev->si_refcount == 0) { 168 LIST_REMOVE(dev, si_list); 169 flag = 1; 170 } 171 dev_unlock(); 172 if (flag) 173 devfs_free(dev); 174} 175 176struct cdevsw * 177dev_refthread(struct cdev *dev, int *ref) 178{ 179 struct cdevsw *csw; 180 struct cdev_priv *cdp; 181 182 mtx_assert(&devmtx, MA_NOTOWNED); 183 if ((dev->si_flags & SI_ETERNAL) != 0) { 184 *ref = 0; 185 return (dev->si_devsw); 186 } 187 dev_lock(); 188 csw = dev->si_devsw; 189 if (csw != NULL) { 190 cdp = cdev2priv(dev); 191 if ((cdp->cdp_flags & CDP_SCHED_DTR) == 0) 192 atomic_add_long(&dev->si_threadcount, 1); 193 else 194 csw = NULL; 195 } 196 dev_unlock(); 197 *ref = 1; 198 return (csw); 199} 200 201struct cdevsw * 202devvn_refthread(struct vnode *vp, struct cdev **devp, int *ref) 203{ 204 struct cdevsw *csw; 205 struct cdev_priv *cdp; 206 struct cdev *dev; 207 208 mtx_assert(&devmtx, MA_NOTOWNED); 209 if ((vp->v_vflag & VV_ETERNALDEV) != 0) { 210 dev = vp->v_rdev; 211 if (dev == NULL) 212 return (NULL); 213 KASSERT((dev->si_flags & SI_ETERNAL) != 0, 214 ("Not eternal cdev")); 215 *ref = 0; 216 csw = dev->si_devsw; 217 KASSERT(csw != NULL, ("Eternal cdev is destroyed")); 218 *devp = dev; 219 return (csw); 220 } 221 222 csw = NULL; 223 dev_lock(); 224 dev = vp->v_rdev; 225 if (dev == NULL) { 226 dev_unlock(); 227 return (NULL); 228 } 229 cdp = cdev2priv(dev); 230 if ((cdp->cdp_flags & CDP_SCHED_DTR) == 0) { 231 csw = dev->si_devsw; 232 if (csw != NULL) 233 atomic_add_long(&dev->si_threadcount, 1); 234 } 235 dev_unlock(); 236 if (csw != NULL) { 237 *devp = dev; 238 *ref = 1; 239 } 240 return (csw); 241} 242 243void 244dev_relthread(struct cdev *dev, int ref) 245{ 246 247 mtx_assert(&devmtx, MA_NOTOWNED); 248 if (!ref) 249 return; 250 KASSERT(dev->si_threadcount > 0, 251 ("%s threadcount is wrong", dev->si_name)); 252 atomic_subtract_rel_long(&dev->si_threadcount, 1); 253} 254 255int 256nullop(void) 257{ 258 259 return (0); 260} 261 262int 263eopnotsupp(void) 264{ 265 266 return (EOPNOTSUPP); 267} 268 269static int 270enxio(void) 271{ 272 return (ENXIO); 273} 274 275static int 276enodev(void) 277{ 278 return (ENODEV); 279} 280 281/* Define a dead_cdevsw for use when devices leave unexpectedly. */ 282 283#define dead_open (d_open_t *)enxio 284#define dead_close (d_close_t *)enxio 285#define dead_read (d_read_t *)enxio 286#define dead_write (d_write_t *)enxio 287#define dead_ioctl (d_ioctl_t *)enxio 288#define dead_poll (d_poll_t *)enodev 289#define dead_mmap (d_mmap_t *)enodev 290 291static void 292dead_strategy(struct bio *bp) 293{ 294 295 biofinish(bp, NULL, ENXIO); 296} 297 298#define dead_dump (dumper_t *)enxio 299#define dead_kqfilter (d_kqfilter_t *)enxio 300#define dead_mmap_single (d_mmap_single_t *)enodev 301 302static struct cdevsw dead_cdevsw = { 303 .d_version = D_VERSION, 304 .d_open = dead_open, 305 .d_close = dead_close, 306 .d_read = dead_read, 307 .d_write = dead_write, 308 .d_ioctl = dead_ioctl, 309 .d_poll = dead_poll, 310 .d_mmap = dead_mmap, 311 .d_strategy = dead_strategy, 312 .d_name = "dead", 313 .d_dump = dead_dump, 314 .d_kqfilter = dead_kqfilter, 315 .d_mmap_single = dead_mmap_single 316}; 317 318/* Default methods if driver does not specify method */ 319 320#define null_open (d_open_t *)nullop 321#define null_close (d_close_t *)nullop 322#define no_read (d_read_t *)enodev 323#define no_write (d_write_t *)enodev 324#define no_ioctl (d_ioctl_t *)enodev 325#define no_mmap (d_mmap_t *)enodev 326#define no_kqfilter (d_kqfilter_t *)enodev 327#define no_mmap_single (d_mmap_single_t *)enodev 328 329static void 330no_strategy(struct bio *bp) 331{ 332 333 biofinish(bp, NULL, ENODEV); 334} 335 336static int 337no_poll(struct cdev *dev __unused, int events, struct thread *td __unused) 338{ 339 340 return (poll_no_poll(events)); 341} 342 343#define no_dump (dumper_t *)enodev 344 345static int 346giant_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 361static int 362giant_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 377static int 378giant_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 393static void 394giant_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 412static int 413giant_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 428static int 429giant_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 444static int 445giant_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 460static int 461giant_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 476static int 477giant_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 492static int 493giant_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 510static int 511giant_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 528static void 529notify(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_f("DEVFS", "CDEV", ev, data, mflags); 545 free(data, M_TEMP); 546} 547 548static void 549notify_create(struct cdev *dev, int flags) 550{ 551 552 notify(dev, "CREATE", flags); 553} 554 555static void 556notify_destroy(struct cdev *dev) 557{ 558 559 notify(dev, "DESTROY", MAKEDEV_WAITOK); 560} 561 562static struct cdev * 563newdev(struct make_dev_args *args, struct cdev *si) 564{ 565 struct cdev *si2; 566 struct cdevsw *csw; 567 568 mtx_assert(&devmtx, MA_OWNED); 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 608static void 609fini_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 622static int 623prep_cdevsw(struct cdevsw *devsw, int flags) 624{ 625 struct cdevsw *dsw2; 626 627 mtx_assert(&devmtx, MA_OWNED); 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_03) { 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_dump = dead_dump; 660 devsw->d_kqfilter = dead_kqfilter; 661 } 662 663 if (devsw->d_flags & D_NEEDGIANT) { 664 if (devsw->d_gianttrick == NULL) { 665 memcpy(dsw2, devsw, sizeof *dsw2); 666 devsw->d_gianttrick = dsw2; 667 dsw2 = NULL; 668 } 669 } 670 671#define FIXUP(member, noop, giant) \ 672 do { \ 673 if (devsw->member == NULL) { \ 674 devsw->member = noop; \ 675 } else if (devsw->d_flags & D_NEEDGIANT) \ 676 devsw->member = giant; \ 677 } \ 678 while (0) 679 680 FIXUP(d_open, null_open, giant_open); 681 FIXUP(d_fdopen, NULL, giant_fdopen); 682 FIXUP(d_close, null_close, giant_close); 683 FIXUP(d_read, no_read, giant_read); 684 FIXUP(d_write, no_write, giant_write); 685 FIXUP(d_ioctl, no_ioctl, giant_ioctl); 686 FIXUP(d_poll, no_poll, giant_poll); 687 FIXUP(d_mmap, no_mmap, giant_mmap); 688 FIXUP(d_strategy, no_strategy, giant_strategy); 689 FIXUP(d_kqfilter, no_kqfilter, giant_kqfilter); 690 FIXUP(d_mmap_single, no_mmap_single, giant_mmap_single); 691 692 if (devsw->d_dump == NULL) devsw->d_dump = no_dump; 693 694 LIST_INIT(&devsw->d_devs); 695 696 devsw->d_flags |= D_INIT; 697 698 if (dsw2 != NULL) 699 cdevsw_free_devlocked(dsw2); 700 return (0); 701} 702 703static int 704prep_devname(struct cdev *dev, const char *fmt, va_list ap) 705{ 706 int len; 707 char *from, *q, *s, *to; 708 709 mtx_assert(&devmtx, MA_OWNED); 710 711 len = vsnrprintf(dev->si_name, sizeof(dev->si_name), 32, fmt, ap); 712 if (len > sizeof(dev->si_name) - 1) 713 return (ENAMETOOLONG); 714 715 /* Strip leading slashes. */ 716 for (from = dev->si_name; *from == '/'; from++) 717 ; 718 719 for (to = dev->si_name; *from != '\0'; from++, to++) { 720 /* 721 * Spaces and double quotation marks cause 722 * problems for the devctl(4) protocol. 723 * Reject names containing those characters. 724 */ 725 if (isspace(*from) || *from == '"') 726 return (EINVAL); 727 /* Treat multiple sequential slashes as single. */ 728 while (from[0] == '/' && from[1] == '/') 729 from++; 730 /* Trailing slash is considered invalid. */ 731 if (from[0] == '/' && from[1] == '\0') 732 return (EINVAL); 733 *to = *from; 734 } 735 *to = '\0'; 736 737 if (dev->si_name[0] == '\0') 738 return (EINVAL); 739 740 /* Disallow "." and ".." components. */ 741 for (s = dev->si_name;;) { 742 for (q = s; *q != '/' && *q != '\0'; q++) 743 ; 744 if (q - s == 1 && s[0] == '.') 745 return (EINVAL); 746 if (q - s == 2 && s[0] == '.' && s[1] == '.') 747 return (EINVAL); 748 if (*q != '/') 749 break; 750 s = q + 1; 751 } 752 753 if (devfs_dev_exists(dev->si_name) != 0) 754 return (EEXIST); 755 756 return (0); 757} 758 759void 760make_dev_args_init_impl(struct make_dev_args *args, size_t sz) 761{ 762 763 bzero(args, sz); 764 args->mda_size = sz; 765} 766 767static int 768make_dev_sv(struct make_dev_args *args1, struct cdev **dres, 769 const char *fmt, va_list ap) 770{ 771 struct cdev *dev, *dev_new; 772 struct make_dev_args args; 773 int res; 774 775 bzero(&args, sizeof(args)); 776 if (sizeof(args) < args1->mda_size) 777 return (EINVAL); 778 bcopy(args1, &args, args1->mda_size); 779 KASSERT((args.mda_flags & MAKEDEV_WAITOK) == 0 || 780 (args.mda_flags & MAKEDEV_NOWAIT) == 0, 781 ("make_dev_sv: both WAITOK and NOWAIT specified")); 782 dev_new = devfs_alloc(args.mda_flags); 783 if (dev_new == NULL) 784 return (ENOMEM); 785 dev_lock(); 786 res = prep_cdevsw(args.mda_devsw, args.mda_flags); 787 if (res != 0) { 788 dev_unlock(); 789 devfs_free(dev_new); 790 return (res); 791 } 792 dev = newdev(&args, dev_new); 793 if ((dev->si_flags & SI_NAMED) == 0) { 794 res = prep_devname(dev, fmt, ap); 795 if (res != 0) { 796 if ((args.mda_flags & MAKEDEV_CHECKNAME) == 0) { 797 panic( 798 "make_dev_sv: bad si_name (error=%d, si_name=%s)", 799 res, dev->si_name); 800 } 801 if (dev == dev_new) { 802 LIST_REMOVE(dev, si_list); 803 dev_unlock(); 804 devfs_free(dev); 805 } else 806 dev_unlock(); 807 return (res); 808 } 809 } 810 if ((args.mda_flags & MAKEDEV_REF) != 0) 811 dev_refl(dev); 812 if ((args.mda_flags & MAKEDEV_ETERNAL) != 0) 813 dev->si_flags |= SI_ETERNAL; 814 KASSERT(!(dev->si_flags & SI_NAMED), 815 ("make_dev() by driver %s on pre-existing device (min=%x, name=%s)", 816 args.mda_devsw->d_name, dev2unit(dev), devtoname(dev))); 817 dev->si_flags |= SI_NAMED; 818 if (args.mda_cr != NULL) 819 dev->si_cred = crhold(args.mda_cr); 820 dev->si_uid = args.mda_uid; 821 dev->si_gid = args.mda_gid; 822 dev->si_mode = args.mda_mode; 823 824 devfs_create(dev); 825 clean_unrhdrl(devfs_inos); 826 dev_unlock_and_free(); 827 828 notify_create(dev, args.mda_flags); 829 830 *dres = dev; 831 return (0); 832} 833 834int 835make_dev_s(struct make_dev_args *args, struct cdev **dres, 836 const char *fmt, ...) 837{ 838 va_list ap; 839 int res; 840 841 va_start(ap, fmt); 842 res = make_dev_sv(args, dres, fmt, ap); 843 va_end(ap); 844 return (res); 845} 846 847static int 848make_dev_credv(int flags, struct cdev **dres, struct cdevsw *devsw, int unit, 849 struct ucred *cr, uid_t uid, gid_t gid, int mode, const char *fmt, 850 va_list ap) 851{ 852 struct make_dev_args args; 853 854 make_dev_args_init(&args); 855 args.mda_flags = flags; 856 args.mda_devsw = devsw; 857 args.mda_cr = cr; 858 args.mda_uid = uid; 859 args.mda_gid = gid; 860 args.mda_mode = mode; 861 args.mda_unit = unit; 862 return (make_dev_sv(&args, dres, fmt, ap)); 863} 864 865struct cdev * 866make_dev(struct cdevsw *devsw, int unit, uid_t uid, gid_t gid, int mode, 867 const char *fmt, ...) 868{ 869 struct cdev *dev; 870 va_list ap; 871 int res; 872 873 va_start(ap, fmt); 874 res = make_dev_credv(0, &dev, devsw, unit, NULL, uid, gid, mode, fmt, 875 ap); 876 va_end(ap); 877 KASSERT(res == 0 && dev != NULL, 878 ("make_dev: failed make_dev_credv (error=%d)", res)); 879 return (dev); 880} 881 882struct cdev * 883make_dev_cred(struct cdevsw *devsw, int unit, struct ucred *cr, uid_t uid, 884 gid_t gid, int mode, const char *fmt, ...) 885{ 886 struct cdev *dev; 887 va_list ap; 888 int res; 889 890 va_start(ap, fmt); 891 res = make_dev_credv(0, &dev, devsw, unit, cr, uid, gid, mode, fmt, ap); 892 va_end(ap); 893 894 KASSERT(res == 0 && dev != NULL, 895 ("make_dev_cred: failed make_dev_credv (error=%d)", res)); 896 return (dev); 897} 898 899struct cdev * 900make_dev_credf(int flags, struct cdevsw *devsw, int unit, struct ucred *cr, 901 uid_t uid, gid_t gid, int mode, const char *fmt, ...) 902{ 903 struct cdev *dev; 904 va_list ap; 905 int res; 906 907 va_start(ap, fmt); 908 res = make_dev_credv(flags, &dev, devsw, unit, cr, uid, gid, mode, 909 fmt, ap); 910 va_end(ap); 911 912 KASSERT(((flags & MAKEDEV_NOWAIT) != 0 && res == ENOMEM) || 913 ((flags & MAKEDEV_CHECKNAME) != 0 && res != ENOMEM) || res == 0, 914 ("make_dev_credf: failed make_dev_credv (error=%d)", res)); 915 return (res == 0 ? dev : NULL); 916} 917 918int 919make_dev_p(int flags, struct cdev **cdev, struct cdevsw *devsw, 920 struct ucred *cr, uid_t uid, gid_t gid, int mode, const char *fmt, ...) 921{ 922 va_list ap; 923 int res; 924 925 va_start(ap, fmt); 926 res = make_dev_credv(flags, cdev, devsw, 0, cr, uid, gid, mode, 927 fmt, ap); 928 va_end(ap); 929 930 KASSERT(((flags & MAKEDEV_NOWAIT) != 0 && res == ENOMEM) || 931 ((flags & MAKEDEV_CHECKNAME) != 0 && res != ENOMEM) || res == 0, 932 ("make_dev_p: failed make_dev_credv (error=%d)", res)); 933 return (res); 934} 935 936static void 937dev_dependsl(struct cdev *pdev, struct cdev *cdev) 938{ 939 940 cdev->si_parent = pdev; 941 cdev->si_flags |= SI_CHILD; 942 LIST_INSERT_HEAD(&pdev->si_children, cdev, si_siblings); 943} 944 945 946void 947dev_depends(struct cdev *pdev, struct cdev *cdev) 948{ 949 950 dev_lock(); 951 dev_dependsl(pdev, cdev); 952 dev_unlock(); 953} 954 955static int 956make_dev_alias_v(int flags, struct cdev **cdev, struct cdev *pdev, 957 const char *fmt, va_list ap) 958{ 959 struct cdev *dev; 960 int error; 961 962 KASSERT(pdev != NULL, ("make_dev_alias_v: pdev is NULL")); 963 KASSERT((flags & MAKEDEV_WAITOK) == 0 || (flags & MAKEDEV_NOWAIT) == 0, 964 ("make_dev_alias_v: both WAITOK and NOWAIT specified")); 965 KASSERT((flags & ~(MAKEDEV_WAITOK | MAKEDEV_NOWAIT | 966 MAKEDEV_CHECKNAME)) == 0, 967 ("make_dev_alias_v: invalid flags specified (flags=%02x)", flags)); 968 969 dev = devfs_alloc(flags); 970 if (dev == NULL) 971 return (ENOMEM); 972 dev_lock(); 973 dev->si_flags |= SI_ALIAS; 974 error = prep_devname(dev, fmt, ap); 975 if (error != 0) { 976 if ((flags & MAKEDEV_CHECKNAME) == 0) { 977 panic("make_dev_alias_v: bad si_name " 978 "(error=%d, si_name=%s)", error, dev->si_name); 979 } 980 dev_unlock(); 981 devfs_free(dev); 982 return (error); 983 } 984 dev->si_flags |= SI_NAMED; 985 devfs_create(dev); 986 dev_dependsl(pdev, dev); 987 clean_unrhdrl(devfs_inos); 988 dev_unlock(); 989 990 notify_create(dev, flags); 991 *cdev = dev; 992 993 return (0); 994} 995 996struct cdev * 997make_dev_alias(struct cdev *pdev, const char *fmt, ...) 998{ 999 struct cdev *dev; 1000 va_list ap; 1001 int res; 1002 1003 va_start(ap, fmt); 1004 res = make_dev_alias_v(MAKEDEV_WAITOK, &dev, pdev, fmt, ap); 1005 va_end(ap); 1006 1007 KASSERT(res == 0 && dev != NULL, 1008 ("make_dev_alias: failed make_dev_alias_v (error=%d)", res)); 1009 return (dev); 1010} 1011 1012int 1013make_dev_alias_p(int flags, struct cdev **cdev, struct cdev *pdev, 1014 const char *fmt, ...) 1015{ 1016 va_list ap; 1017 int res; 1018 1019 va_start(ap, fmt); 1020 res = make_dev_alias_v(flags, cdev, pdev, fmt, ap); 1021 va_end(ap); 1022 return (res); 1023} 1024 1025int 1026make_dev_physpath_alias(int flags, struct cdev **cdev, struct cdev *pdev, 1027 struct cdev *old_alias, const char *physpath) 1028{ 1029 char *devfspath; 1030 int physpath_len; 1031 int max_parentpath_len; 1032 int parentpath_len; 1033 int devfspathbuf_len; 1034 int mflags; 1035 int ret; 1036 1037 *cdev = NULL; 1038 devfspath = NULL; 1039 physpath_len = strlen(physpath); 1040 ret = EINVAL; 1041 if (physpath_len == 0) 1042 goto out; 1043 1044 if (strncmp("id1,", physpath, 4) == 0) { 1045 physpath += 4; 1046 physpath_len -= 4; 1047 if (physpath_len == 0) 1048 goto out; 1049 } 1050 1051 max_parentpath_len = SPECNAMELEN - physpath_len - /*/*/1; 1052 parentpath_len = strlen(pdev->si_name); 1053 if (max_parentpath_len < parentpath_len) { 1054 if (bootverbose) 1055 printf("WARNING: Unable to alias %s " 1056 "to %s/%s - path too long\n", 1057 pdev->si_name, physpath, pdev->si_name); 1058 ret = ENAMETOOLONG; 1059 goto out; 1060 } 1061 1062 mflags = (flags & MAKEDEV_NOWAIT) ? M_NOWAIT : M_WAITOK; 1063 devfspathbuf_len = physpath_len + /*/*/1 + parentpath_len + /*NUL*/1; 1064 devfspath = malloc(devfspathbuf_len, M_DEVBUF, mflags); 1065 if (devfspath == NULL) { 1066 ret = ENOMEM; 1067 goto out; 1068 } 1069 1070 sprintf(devfspath, "%s/%s", physpath, pdev->si_name); 1071 if (old_alias != NULL && strcmp(old_alias->si_name, devfspath) == 0) { 1072 /* Retain the existing alias. */ 1073 *cdev = old_alias; 1074 old_alias = NULL; 1075 ret = 0; 1076 } else { 1077 ret = make_dev_alias_p(flags, cdev, pdev, "%s", devfspath); 1078 } 1079out: 1080 if (old_alias != NULL) 1081 destroy_dev(old_alias); 1082 if (devfspath != NULL) 1083 free(devfspath, M_DEVBUF); 1084 return (ret); 1085} 1086 1087static void 1088destroy_devl(struct cdev *dev) 1089{ 1090 struct cdevsw *csw; 1091 struct cdev_privdata *p; 1092 struct cdev_priv *cdp; 1093 1094 mtx_assert(&devmtx, MA_OWNED); 1095 KASSERT(dev->si_flags & SI_NAMED, 1096 ("WARNING: Driver mistake: destroy_dev on %d\n", dev2unit(dev))); 1097 KASSERT((dev->si_flags & SI_ETERNAL) == 0, 1098 ("WARNING: Driver mistake: destroy_dev on eternal %d\n", 1099 dev2unit(dev))); 1100 1101 cdp = cdev2priv(dev); 1102 if ((cdp->cdp_flags & CDP_UNREF_DTR) == 0) { 1103 /* 1104 * Avoid race with dev_rel(), e.g. from the populate 1105 * loop. If CDP_UNREF_DTR flag is set, the reference 1106 * to be dropped at the end of destroy_devl() was 1107 * already taken by delist_dev_locked(). 1108 */ 1109 dev_refl(dev); 1110 1111 devfs_destroy(dev); 1112 } 1113 1114 /* Remove name marking */ 1115 dev->si_flags &= ~SI_NAMED; 1116 1117 /* If we are a child, remove us from the parents list */ 1118 if (dev->si_flags & SI_CHILD) { 1119 LIST_REMOVE(dev, si_siblings); 1120 dev->si_flags &= ~SI_CHILD; 1121 } 1122 1123 /* Kill our children */ 1124 while (!LIST_EMPTY(&dev->si_children)) 1125 destroy_devl(LIST_FIRST(&dev->si_children)); 1126 1127 /* Remove from clone list */ 1128 if (dev->si_flags & SI_CLONELIST) { 1129 LIST_REMOVE(dev, si_clone); 1130 dev->si_flags &= ~SI_CLONELIST; 1131 } 1132 1133 csw = dev->si_devsw; 1134 dev->si_devsw = NULL; /* already NULL for SI_ALIAS */ 1135 while (csw != NULL && csw->d_purge != NULL && dev->si_threadcount) { 1136 csw->d_purge(dev); 1137 msleep(csw, &devmtx, PRIBIO, "devprg", hz/10); 1138 if (dev->si_threadcount) 1139 printf("Still %lu threads in %s\n", 1140 dev->si_threadcount, devtoname(dev)); 1141 } 1142 while (dev->si_threadcount != 0) { 1143 /* Use unique dummy wait ident */ 1144 msleep(&csw, &devmtx, PRIBIO, "devdrn", hz / 10); 1145 } 1146 1147 dev_unlock(); 1148 if ((cdp->cdp_flags & CDP_UNREF_DTR) == 0) { 1149 /* avoid out of order notify events */ 1150 notify_destroy(dev); 1151 } 1152 mtx_lock(&cdevpriv_mtx); 1153 while ((p = LIST_FIRST(&cdp->cdp_fdpriv)) != NULL) { 1154 devfs_destroy_cdevpriv(p); 1155 mtx_lock(&cdevpriv_mtx); 1156 } 1157 mtx_unlock(&cdevpriv_mtx); 1158 dev_lock(); 1159 1160 dev->si_drv1 = 0; 1161 dev->si_drv2 = 0; 1162 bzero(&dev->__si_u, sizeof(dev->__si_u)); 1163 1164 if (!(dev->si_flags & SI_ALIAS)) { 1165 /* Remove from cdevsw list */ 1166 LIST_REMOVE(dev, si_list); 1167 1168 /* If cdevsw has no more struct cdev *'s, clean it */ 1169 if (LIST_EMPTY(&csw->d_devs)) { 1170 fini_cdevsw(csw); 1171 wakeup(&csw->d_devs); 1172 } 1173 } 1174 dev->si_flags &= ~SI_ALIAS; 1175 cdp->cdp_flags &= ~CDP_UNREF_DTR; 1176 dev->si_refcount--; 1177 1178 if (dev->si_refcount > 0) 1179 LIST_INSERT_HEAD(&dead_cdevsw.d_devs, dev, si_list); 1180 else 1181 dev_free_devlocked(dev); 1182} 1183 1184static void 1185delist_dev_locked(struct cdev *dev) 1186{ 1187 struct cdev_priv *cdp; 1188 struct cdev *child; 1189 1190 mtx_assert(&devmtx, MA_OWNED); 1191 cdp = cdev2priv(dev); 1192 if ((cdp->cdp_flags & CDP_UNREF_DTR) != 0) 1193 return; 1194 cdp->cdp_flags |= CDP_UNREF_DTR; 1195 dev_refl(dev); 1196 devfs_destroy(dev); 1197 LIST_FOREACH(child, &dev->si_children, si_siblings) 1198 delist_dev_locked(child); 1199 dev_unlock(); 1200 /* ensure the destroy event is queued in order */ 1201 notify_destroy(dev); 1202 dev_lock(); 1203} 1204 1205/* 1206 * This function will delist a character device and its children from 1207 * the directory listing and create a destroy event without waiting 1208 * for all character device references to go away. At some later point 1209 * destroy_dev() must be called to complete the character device 1210 * destruction. After calling this function the character device name 1211 * can instantly be re-used. 1212 */ 1213void 1214delist_dev(struct cdev *dev) 1215{ 1216 1217 WITNESS_WARN(WARN_GIANTOK | WARN_SLEEPOK, NULL, "delist_dev"); 1218 dev_lock(); 1219 delist_dev_locked(dev); 1220 dev_unlock(); 1221} 1222 1223void 1224destroy_dev(struct cdev *dev) 1225{ 1226 1227 WITNESS_WARN(WARN_GIANTOK | WARN_SLEEPOK, NULL, "destroy_dev"); 1228 dev_lock(); 1229 destroy_devl(dev); 1230 dev_unlock_and_free(); 1231} 1232 1233const char * 1234devtoname(struct cdev *dev) 1235{ 1236 1237 return (dev->si_name); 1238} 1239 1240int 1241dev_stdclone(char *name, char **namep, const char *stem, int *unit) 1242{ 1243 int u, i; 1244 1245 i = strlen(stem); 1246 if (bcmp(stem, name, i) != 0) 1247 return (0); 1248 if (!isdigit(name[i])) 1249 return (0); 1250 u = 0; 1251 if (name[i] == '0' && isdigit(name[i+1])) 1252 return (0); 1253 while (isdigit(name[i])) { 1254 u *= 10; 1255 u += name[i++] - '0'; 1256 } 1257 if (u > 0xffffff) 1258 return (0); 1259 *unit = u; 1260 if (namep) 1261 *namep = &name[i]; 1262 if (name[i]) 1263 return (2); 1264 return (1); 1265} 1266 1267/* 1268 * Helper functions for cloning device drivers. 1269 * 1270 * The objective here is to make it unnecessary for the device drivers to 1271 * use rman or similar to manage their unit number space. Due to the way 1272 * we do "on-demand" devices, using rman or other "private" methods 1273 * will be very tricky to lock down properly once we lock down this file. 1274 * 1275 * Instead we give the drivers these routines which puts the struct cdev *'s 1276 * that are to be managed on their own list, and gives the driver the ability 1277 * to ask for the first free unit number or a given specified unit number. 1278 * 1279 * In addition these routines support paired devices (pty, nmdm and similar) 1280 * by respecting a number of "flag" bits in the minor number. 1281 * 1282 */ 1283 1284struct clonedevs { 1285 LIST_HEAD(,cdev) head; 1286}; 1287 1288void 1289clone_setup(struct clonedevs **cdp) 1290{ 1291 1292 *cdp = malloc(sizeof **cdp, M_DEVBUF, M_WAITOK | M_ZERO); 1293 LIST_INIT(&(*cdp)->head); 1294} 1295 1296int 1297clone_create(struct clonedevs **cdp, struct cdevsw *csw, int *up, 1298 struct cdev **dp, int extra) 1299{ 1300 struct clonedevs *cd; 1301 struct cdev *dev, *ndev, *dl, *de; 1302 struct make_dev_args args; 1303 int unit, low, u; 1304 1305 KASSERT(*cdp != NULL, 1306 ("clone_setup() not called in driver \"%s\"", csw->d_name)); 1307 KASSERT(!(extra & CLONE_UNITMASK), 1308 ("Illegal extra bits (0x%x) in clone_create", extra)); 1309 KASSERT(*up <= CLONE_UNITMASK, 1310 ("Too high unit (0x%x) in clone_create", *up)); 1311 KASSERT(csw->d_flags & D_NEEDMINOR, 1312 ("clone_create() on cdevsw without minor numbers")); 1313 1314 1315 /* 1316 * Search the list for a lot of things in one go: 1317 * A preexisting match is returned immediately. 1318 * The lowest free unit number if we are passed -1, and the place 1319 * in the list where we should insert that new element. 1320 * The place to insert a specified unit number, if applicable 1321 * the end of the list. 1322 */ 1323 unit = *up; 1324 ndev = devfs_alloc(MAKEDEV_WAITOK); 1325 dev_lock(); 1326 prep_cdevsw(csw, MAKEDEV_WAITOK); 1327 low = extra; 1328 de = dl = NULL; 1329 cd = *cdp; 1330 LIST_FOREACH(dev, &cd->head, si_clone) { 1331 KASSERT(dev->si_flags & SI_CLONELIST, 1332 ("Dev %p(%s) should be on clonelist", dev, dev->si_name)); 1333 u = dev2unit(dev); 1334 if (u == (unit | extra)) { 1335 *dp = dev; 1336 dev_unlock(); 1337 devfs_free(ndev); 1338 return (0); 1339 } 1340 if (unit == -1 && u == low) { 1341 low++; 1342 de = dev; 1343 continue; 1344 } else if (u < (unit | extra)) { 1345 de = dev; 1346 continue; 1347 } else if (u > (unit | extra)) { 1348 dl = dev; 1349 break; 1350 } 1351 } 1352 if (unit == -1) 1353 unit = low & CLONE_UNITMASK; 1354 make_dev_args_init(&args); 1355 args.mda_unit = unit | extra; 1356 args.mda_devsw = csw; 1357 dev = newdev(&args, ndev); 1358 if (dev->si_flags & SI_CLONELIST) { 1359 printf("dev %p (%s) is on clonelist\n", dev, dev->si_name); 1360 printf("unit=%d, low=%d, extra=0x%x\n", unit, low, extra); 1361 LIST_FOREACH(dev, &cd->head, si_clone) { 1362 printf("\t%p %s\n", dev, dev->si_name); 1363 } 1364 panic("foo"); 1365 } 1366 KASSERT(!(dev->si_flags & SI_CLONELIST), 1367 ("Dev %p(%s) should not be on clonelist", dev, dev->si_name)); 1368 if (dl != NULL) 1369 LIST_INSERT_BEFORE(dl, dev, si_clone); 1370 else if (de != NULL) 1371 LIST_INSERT_AFTER(de, dev, si_clone); 1372 else 1373 LIST_INSERT_HEAD(&cd->head, dev, si_clone); 1374 dev->si_flags |= SI_CLONELIST; 1375 *up = unit; 1376 dev_unlock_and_free(); 1377 return (1); 1378} 1379 1380/* 1381 * Kill everything still on the list. The driver should already have 1382 * disposed of any softc hung of the struct cdev *'s at this time. 1383 */ 1384void 1385clone_cleanup(struct clonedevs **cdp) 1386{ 1387 struct cdev *dev; 1388 struct cdev_priv *cp; 1389 struct clonedevs *cd; 1390 1391 cd = *cdp; 1392 if (cd == NULL) 1393 return; 1394 dev_lock(); 1395 while (!LIST_EMPTY(&cd->head)) { 1396 dev = LIST_FIRST(&cd->head); 1397 LIST_REMOVE(dev, si_clone); 1398 KASSERT(dev->si_flags & SI_CLONELIST, 1399 ("Dev %p(%s) should be on clonelist", dev, dev->si_name)); 1400 dev->si_flags &= ~SI_CLONELIST; 1401 cp = cdev2priv(dev); 1402 if (!(cp->cdp_flags & CDP_SCHED_DTR)) { 1403 cp->cdp_flags |= CDP_SCHED_DTR; 1404 KASSERT(dev->si_flags & SI_NAMED, 1405 ("Driver has goofed in cloning underways udev %jx unit %x", 1406 (uintmax_t)dev2udev(dev), dev2unit(dev))); 1407 destroy_devl(dev); 1408 } 1409 } 1410 dev_unlock_and_free(); 1411 free(cd, M_DEVBUF); 1412 *cdp = NULL; 1413} 1414 1415static TAILQ_HEAD(, cdev_priv) dev_ddtr = 1416 TAILQ_HEAD_INITIALIZER(dev_ddtr); 1417static struct task dev_dtr_task = TASK_INITIALIZER(0, destroy_dev_tq, NULL); 1418 1419static void 1420destroy_dev_tq(void *ctx, int pending) 1421{ 1422 struct cdev_priv *cp; 1423 struct cdev *dev; 1424 void (*cb)(void *); 1425 void *cb_arg; 1426 1427 dev_lock(); 1428 while (!TAILQ_EMPTY(&dev_ddtr)) { 1429 cp = TAILQ_FIRST(&dev_ddtr); 1430 dev = &cp->cdp_c; 1431 KASSERT(cp->cdp_flags & CDP_SCHED_DTR, 1432 ("cdev %p in dev_destroy_tq without CDP_SCHED_DTR", cp)); 1433 TAILQ_REMOVE(&dev_ddtr, cp, cdp_dtr_list); 1434 cb = cp->cdp_dtr_cb; 1435 cb_arg = cp->cdp_dtr_cb_arg; 1436 destroy_devl(dev); 1437 dev_unlock_and_free(); 1438 dev_rel(dev); 1439 if (cb != NULL) 1440 cb(cb_arg); 1441 dev_lock(); 1442 } 1443 dev_unlock(); 1444} 1445 1446/* 1447 * devmtx shall be locked on entry. devmtx will be unlocked after 1448 * function return. 1449 */ 1450static int 1451destroy_dev_sched_cbl(struct cdev *dev, void (*cb)(void *), void *arg) 1452{ 1453 struct cdev_priv *cp; 1454 1455 mtx_assert(&devmtx, MA_OWNED); 1456 cp = cdev2priv(dev); 1457 if (cp->cdp_flags & CDP_SCHED_DTR) { 1458 dev_unlock(); 1459 return (0); 1460 } 1461 dev_refl(dev); 1462 cp->cdp_flags |= CDP_SCHED_DTR; 1463 cp->cdp_dtr_cb = cb; 1464 cp->cdp_dtr_cb_arg = arg; 1465 TAILQ_INSERT_TAIL(&dev_ddtr, cp, cdp_dtr_list); 1466 dev_unlock(); 1467 taskqueue_enqueue(taskqueue_swi_giant, &dev_dtr_task); 1468 return (1); 1469} 1470 1471int 1472destroy_dev_sched_cb(struct cdev *dev, void (*cb)(void *), void *arg) 1473{ 1474 1475 dev_lock(); 1476 return (destroy_dev_sched_cbl(dev, cb, arg)); 1477} 1478 1479int 1480destroy_dev_sched(struct cdev *dev) 1481{ 1482 1483 return (destroy_dev_sched_cb(dev, NULL, NULL)); 1484} 1485 1486void 1487destroy_dev_drain(struct cdevsw *csw) 1488{ 1489 1490 dev_lock(); 1491 while (!LIST_EMPTY(&csw->d_devs)) { 1492 msleep(&csw->d_devs, &devmtx, PRIBIO, "devscd", hz/10); 1493 } 1494 dev_unlock(); 1495} 1496 1497void 1498drain_dev_clone_events(void) 1499{ 1500 1501 sx_xlock(&clone_drain_lock); 1502 sx_xunlock(&clone_drain_lock); 1503} 1504 1505#include "opt_ddb.h" 1506#ifdef DDB 1507#include <sys/kernel.h> 1508 1509#include <ddb/ddb.h> 1510 1511DB_SHOW_COMMAND(cdev, db_show_cdev) 1512{ 1513 struct cdev_priv *cdp; 1514 struct cdev *dev; 1515 u_int flags; 1516 char buf[512]; 1517 1518 if (!have_addr) { 1519 TAILQ_FOREACH(cdp, &cdevp_list, cdp_list) { 1520 dev = &cdp->cdp_c; 1521 db_printf("%s %p\n", dev->si_name, dev); 1522 if (db_pager_quit) 1523 break; 1524 } 1525 return; 1526 } 1527 1528 dev = (struct cdev *)addr; 1529 cdp = cdev2priv(dev); 1530 db_printf("dev %s ref %d use %ld thr %ld inuse %u fdpriv %p\n", 1531 dev->si_name, dev->si_refcount, dev->si_usecount, 1532 dev->si_threadcount, cdp->cdp_inuse, cdp->cdp_fdpriv.lh_first); 1533 db_printf("devsw %p si_drv0 %d si_drv1 %p si_drv2 %p\n", 1534 dev->si_devsw, dev->si_drv0, dev->si_drv1, dev->si_drv2); 1535 flags = dev->si_flags; 1536#define SI_FLAG(flag) do { \ 1537 if (flags & (flag)) { \ 1538 if (buf[0] != '\0') \ 1539 strlcat(buf, ", ", sizeof(buf)); \ 1540 strlcat(buf, (#flag) + 3, sizeof(buf)); \ 1541 flags &= ~(flag); \ 1542 } \ 1543} while (0) 1544 buf[0] = '\0'; 1545 SI_FLAG(SI_ETERNAL); 1546 SI_FLAG(SI_ALIAS); 1547 SI_FLAG(SI_NAMED); 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