1 /* $NetBSD: kern_module.c,v 1.57 2010/01/19 15:23:14 pooka Exp $ */ 2 3 /*- 4 * Copyright (c) 2008 The NetBSD Foundation, Inc. 5 * All rights reserved. 6 * 7 * This code is derived from software developed for The NetBSD Foundation 8 * by Andrew Doran. 9 * 10 * Redistribution and use in source and binary forms, with or without 11 * modification, are permitted provided that the following conditions 12 * are met: 13 * 1. Redistributions of source code must retain the above copyright 14 * notice, this list of conditions and the following disclaimer. 15 * 2. Redistributions in binary form must reproduce the above copyright 16 * notice, this list of conditions and the following disclaimer in the 17 * documentation and/or other materials provided with the distribution. 18 * 19 * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS 20 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED 21 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR 22 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS 23 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR 24 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 25 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 26 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 27 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 28 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 29 * POSSIBILITY OF SUCH DAMAGE. 30 */ 31 32 /* 33 * Kernel module support. 34 */ 35 36 #include <sys/cdefs.h> 37 __KERNEL_RCSID(0, "$NetBSD: kern_module.c,v 1.57 2010/01/19 15:23:14 pooka Exp $"); 38 39 #define _MODULE_INTERNAL 40 41 #ifdef _KERNEL_OPT 42 #include "opt_ddb.h" 43 #include "opt_modular.h" 44 #endif 45 46 #include <sys/param.h> 47 #include <sys/systm.h> 48 #include <sys/kernel.h> 49 #include <sys/proc.h> 50 #include <sys/kauth.h> 51 #include <sys/kobj.h> 52 #include <sys/kmem.h> 53 #include <sys/module.h> 54 #include <sys/kauth.h> 55 #include <sys/kthread.h> 56 #include <sys/sysctl.h> 57 #include <sys/lock.h> 58 59 #include <uvm/uvm_extern.h> 60 61 #include <machine/stdarg.h> 62 63 struct vm_map *module_map; 64 char module_base[MODULE_BASE_SIZE]; 65 66 struct modlist module_list = TAILQ_HEAD_INITIALIZER(module_list); 67 struct modlist module_bootlist = TAILQ_HEAD_INITIALIZER(module_bootlist); 68 static module_t *module_active; 69 static int module_verbose_on; 70 static int module_autoload_on = 1; 71 u_int module_count; 72 kmutex_t module_lock; 73 u_int module_autotime = 10; 74 u_int module_gen = 1; 75 static kcondvar_t module_thread_cv; 76 static kmutex_t module_thread_lock; 77 static int module_thread_ticks; 78 79 static kauth_listener_t module_listener; 80 81 /* Ensure that the kernel's link set isn't empty. */ 82 static modinfo_t module_dummy; 83 __link_set_add_rodata(modules, module_dummy); 84 85 static int module_do_load(const char *, bool, int, prop_dictionary_t, 86 module_t **, modclass_t class, bool); 87 static int module_do_unload(const char *); 88 static int module_do_builtin(const char *, module_t **); 89 static int module_fetch_info(module_t *); 90 static void module_thread(void *); 91 92 static bool module_merge_dicts(prop_dictionary_t, const prop_dictionary_t); 93 94 int module_eopnotsupp(void); 95 96 int 97 module_eopnotsupp(void) 98 { 99 100 return EOPNOTSUPP; 101 } 102 __weak_alias(module_load_vfs,module_eopnotsupp); 103 104 /* 105 * module_error: 106 * 107 * Utility function: log an error. 108 */ 109 void 110 module_error(const char *fmt, ...) 111 { 112 va_list ap; 113 114 va_start(ap, fmt); 115 printf("WARNING: module error: "); 116 vprintf(fmt, ap); 117 printf("\n"); 118 va_end(ap); 119 } 120 121 /* 122 * module_print: 123 * 124 * Utility function: log verbose output. 125 */ 126 void 127 module_print(const char *fmt, ...) 128 { 129 va_list ap; 130 131 if (module_verbose_on) { 132 va_start(ap, fmt); 133 printf("DEBUG: module: "); 134 vprintf(fmt, ap); 135 printf("\n"); 136 va_end(ap); 137 } 138 } 139 140 static int 141 module_listener_cb(kauth_cred_t cred, kauth_action_t action, void *cookie, 142 void *arg0, void *arg1, void *arg2, void *arg3) 143 { 144 int result; 145 146 result = KAUTH_RESULT_DEFER; 147 148 if (action != KAUTH_SYSTEM_MODULE) 149 return result; 150 151 if ((uintptr_t)arg2 != 0) /* autoload */ 152 result = KAUTH_RESULT_ALLOW; 153 154 return result; 155 } 156 157 /* 158 * module_init: 159 * 160 * Initialize the module subsystem. 161 */ 162 void 163 module_init(void) 164 { 165 extern struct vm_map *module_map; 166 167 if (module_map == NULL) { 168 module_map = kernel_map; 169 } 170 mutex_init(&module_lock, MUTEX_DEFAULT, IPL_NONE); 171 cv_init(&module_thread_cv, "modunload"); 172 mutex_init(&module_thread_lock, MUTEX_DEFAULT, IPL_NONE); 173 #ifdef MODULAR /* XXX */ 174 module_init_md(); 175 #endif 176 177 #if __NetBSD_Version__ / 1000000 % 100 == 99 /* -current */ 178 snprintf(module_base, sizeof(module_base), "/stand/%s/%s/modules", 179 machine, osrelease); 180 #else /* release */ 181 snprintf(module_base, sizeof(module_base), "/stand/%s/%d.%d/modules", 182 machine, __NetBSD_Version__ / 100000000, 183 __NetBSD_Version__ / 1000000 % 100); 184 #endif 185 186 module_listener = kauth_listen_scope(KAUTH_SCOPE_SYSTEM, 187 module_listener_cb, NULL); 188 } 189 190 /* 191 * module_init2: 192 * 193 * Start the auto unload kthread. 194 */ 195 void 196 module_init2(void) 197 { 198 int error; 199 200 error = kthread_create(PRI_VM, KTHREAD_MPSAFE, NULL, module_thread, 201 NULL, NULL, "modunload"); 202 if (error != 0) 203 panic("module_init: %d", error); 204 } 205 206 SYSCTL_SETUP(sysctl_module_setup, "sysctl module setup") 207 { 208 const struct sysctlnode *node = NULL; 209 210 sysctl_createv(clog, 0, NULL, NULL, 211 CTLFLAG_PERMANENT, 212 CTLTYPE_NODE, "kern", NULL, 213 NULL, 0, NULL, 0, 214 CTL_KERN, CTL_EOL); 215 sysctl_createv(clog, 0, NULL, &node, 216 CTLFLAG_PERMANENT, 217 CTLTYPE_NODE, "module", 218 SYSCTL_DESCR("Module options"), 219 NULL, 0, NULL, 0, 220 CTL_KERN, CTL_CREATE, CTL_EOL); 221 222 if (node == NULL) 223 return; 224 225 sysctl_createv(clog, 0, &node, NULL, 226 CTLFLAG_PERMANENT | CTLFLAG_READWRITE, 227 CTLTYPE_INT, "autoload", 228 SYSCTL_DESCR("Enable automatic load of modules"), 229 NULL, 0, &module_autoload_on, 0, 230 CTL_CREATE, CTL_EOL); 231 sysctl_createv(clog, 0, &node, NULL, 232 CTLFLAG_PERMANENT | CTLFLAG_READWRITE, 233 CTLTYPE_INT, "verbose", 234 SYSCTL_DESCR("Enable verbose output"), 235 NULL, 0, &module_verbose_on, 0, 236 CTL_CREATE, CTL_EOL); 237 } 238 239 /* 240 * module_init_class: 241 * 242 * Initialize all built-in and pre-loaded modules of the 243 * specified class. 244 */ 245 void 246 module_init_class(modclass_t class) 247 { 248 __link_set_decl(modules, modinfo_t); 249 modinfo_t *const *mip, *mi; 250 module_t *mod; 251 252 mutex_enter(&module_lock); 253 /* 254 * Builtins first. These can't depend on pre-loaded modules. 255 */ 256 __link_set_foreach(mip, modules) { 257 mi = *mip; 258 if (mi == &module_dummy) { 259 continue; 260 } 261 if (class != MODULE_CLASS_ANY && class != mi->mi_class) { 262 continue; 263 } 264 (void)module_do_builtin(mi->mi_name, NULL); 265 } 266 /* 267 * Now preloaded modules. These will be pulled off the 268 * list as we call module_do_load(); 269 */ 270 do { 271 TAILQ_FOREACH(mod, &module_bootlist, mod_chain) { 272 mi = mod->mod_info; 273 if (class != MODULE_CLASS_ANY && 274 class != mi->mi_class) 275 continue; 276 module_do_load(mi->mi_name, false, 0, NULL, NULL, 277 class, false); 278 break; 279 } 280 } while (mod != NULL); 281 mutex_exit(&module_lock); 282 } 283 284 /* 285 * module_compatible: 286 * 287 * Return true if the two supplied kernel versions are said to 288 * have the same binary interface for kernel code. The entire 289 * version is signficant for the development tree (-current), 290 * major and minor versions are significant for official 291 * releases of the system. 292 */ 293 bool 294 module_compatible(int v1, int v2) 295 { 296 297 #if __NetBSD_Version__ / 1000000 % 100 == 99 /* -current */ 298 return v1 == v2; 299 #else /* release */ 300 return abs(v1 - v2) < 10000; 301 #endif 302 } 303 304 /* 305 * module_load: 306 * 307 * Load a single module from the file system. 308 */ 309 int 310 module_load(const char *filename, int flags, prop_dictionary_t props, 311 modclass_t class) 312 { 313 int error; 314 315 /* Authorize. */ 316 error = kauth_authorize_system(kauth_cred_get(), KAUTH_SYSTEM_MODULE, 317 0, (void *)(uintptr_t)MODCTL_LOAD, NULL, NULL); 318 if (error != 0) { 319 return error; 320 } 321 322 mutex_enter(&module_lock); 323 error = module_do_load(filename, false, flags, props, NULL, class, 324 false); 325 mutex_exit(&module_lock); 326 327 return error; 328 } 329 330 /* 331 * module_autoload: 332 * 333 * Load a single module from the file system, system initiated. 334 */ 335 int 336 module_autoload(const char *filename, modclass_t class) 337 { 338 int error; 339 340 KASSERT(mutex_owned(&module_lock)); 341 342 /* Nothing if the user has disabled it. */ 343 if (!module_autoload_on) { 344 return EPERM; 345 } 346 347 /* Disallow path separators and magic symlinks. */ 348 if (strchr(filename, '/') != NULL || strchr(filename, '@') != NULL || 349 strchr(filename, '.') != NULL) { 350 return EPERM; 351 } 352 353 /* Authorize. */ 354 error = kauth_authorize_system(kauth_cred_get(), KAUTH_SYSTEM_MODULE, 355 0, (void *)(uintptr_t)MODCTL_LOAD, (void *)(uintptr_t)1, NULL); 356 if (error != 0) { 357 return error; 358 } 359 360 return module_do_load(filename, false, 0, NULL, NULL, class, true); 361 } 362 363 /* 364 * module_unload: 365 * 366 * Find and unload a module by name. 367 */ 368 int 369 module_unload(const char *name) 370 { 371 int error; 372 373 /* Authorize. */ 374 error = kauth_authorize_system(kauth_cred_get(), KAUTH_SYSTEM_MODULE, 375 0, (void *)(uintptr_t)MODCTL_UNLOAD, NULL, NULL); 376 if (error != 0) { 377 return error; 378 } 379 380 mutex_enter(&module_lock); 381 error = module_do_unload(name); 382 mutex_exit(&module_lock); 383 384 return error; 385 } 386 387 /* 388 * module_lookup: 389 * 390 * Look up a module by name. 391 */ 392 module_t * 393 module_lookup(const char *name) 394 { 395 module_t *mod; 396 397 KASSERT(mutex_owned(&module_lock)); 398 399 TAILQ_FOREACH(mod, &module_list, mod_chain) { 400 if (strcmp(mod->mod_info->mi_name, name) == 0) { 401 break; 402 } 403 } 404 405 return mod; 406 } 407 408 /* 409 * module_hold: 410 * 411 * Add a single reference to a module. It's the caller's 412 * responsibility to ensure that the reference is dropped 413 * later. 414 */ 415 int 416 module_hold(const char *name) 417 { 418 module_t *mod; 419 420 mutex_enter(&module_lock); 421 mod = module_lookup(name); 422 if (mod == NULL) { 423 mutex_exit(&module_lock); 424 return ENOENT; 425 } 426 mod->mod_refcnt++; 427 mutex_exit(&module_lock); 428 429 return 0; 430 } 431 432 /* 433 * module_rele: 434 * 435 * Release a reference acquired with module_hold(). 436 */ 437 void 438 module_rele(const char *name) 439 { 440 module_t *mod; 441 442 mutex_enter(&module_lock); 443 mod = module_lookup(name); 444 if (mod == NULL) { 445 mutex_exit(&module_lock); 446 panic("module_rele: gone"); 447 } 448 mod->mod_refcnt--; 449 mutex_exit(&module_lock); 450 } 451 452 /* 453 * module_enqueue: 454 * 455 * Put a module onto the global list and update counters. 456 */ 457 void 458 module_enqueue(module_t *mod) 459 { 460 int i; 461 462 KASSERT(mutex_owned(&module_lock)); 463 464 /* 465 * If there are requisite modules, put at the head of the queue. 466 * This is so that autounload can unload requisite modules with 467 * only one pass through the queue. 468 */ 469 if (mod->mod_nrequired) { 470 TAILQ_INSERT_HEAD(&module_list, mod, mod_chain); 471 472 /* Add references to the requisite modules. */ 473 for (i = 0; i < mod->mod_nrequired; i++) { 474 KASSERT(mod->mod_required[i] != NULL); 475 mod->mod_required[i]->mod_refcnt++; 476 } 477 } else { 478 TAILQ_INSERT_TAIL(&module_list, mod, mod_chain); 479 } 480 module_count++; 481 module_gen++; 482 } 483 484 /* 485 * module_do_builtin: 486 * 487 * Initialize a single module from the list of modules that are 488 * built into the kernel (linked into the kernel image). 489 */ 490 static int 491 module_do_builtin(const char *name, module_t **modp) 492 { 493 __link_set_decl(modules, modinfo_t); 494 modinfo_t *const *mip; 495 const char *p, *s; 496 char buf[MAXMODNAME]; 497 modinfo_t *mi; 498 module_t *mod, *mod2; 499 size_t len; 500 int error; 501 502 KASSERT(mutex_owned(&module_lock)); 503 504 /* 505 * Check to see if already loaded. 506 */ 507 if ((mod = module_lookup(name)) != NULL) { 508 if (modp != NULL) { 509 *modp = mod; 510 } 511 return 0; 512 } 513 514 /* 515 * Search the list to see if we have a module by this name. 516 */ 517 error = ENOENT; 518 __link_set_foreach(mip, modules) { 519 mi = *mip; 520 if (mi == &module_dummy) { 521 continue; 522 } 523 if (strcmp(mi->mi_name, name) == 0) { 524 error = 0; 525 break; 526 } 527 } 528 if (error != 0) { 529 module_error("can't find `%s'", name); 530 return error; 531 } 532 533 /* 534 * Initialize pre-requisites. 535 */ 536 mod = kmem_zalloc(sizeof(*mod), KM_SLEEP); 537 if (mod == NULL) { 538 module_error("out of memory for `%s'", name); 539 return ENOMEM; 540 } 541 if (modp != NULL) { 542 *modp = mod; 543 } 544 if (mi->mi_required != NULL) { 545 for (s = mi->mi_required; *s != '\0'; s = p) { 546 if (*s == ',') 547 s++; 548 p = s; 549 while (*p != '\0' && *p != ',') 550 p++; 551 len = min(p - s + 1, sizeof(buf)); 552 strlcpy(buf, s, len); 553 if (buf[0] == '\0') 554 break; 555 if (mod->mod_nrequired == MAXMODDEPS - 1) { 556 module_error("too many required modules"); 557 kmem_free(mod, sizeof(*mod)); 558 return EINVAL; 559 } 560 error = module_do_builtin(buf, &mod2); 561 if (error != 0) { 562 kmem_free(mod, sizeof(*mod)); 563 return error; 564 } 565 mod->mod_required[mod->mod_nrequired++] = mod2; 566 } 567 } 568 569 /* 570 * Try to initialize the module. 571 */ 572 KASSERT(module_active == NULL); 573 module_active = mod; 574 error = (*mi->mi_modcmd)(MODULE_CMD_INIT, NULL); 575 module_active = NULL; 576 if (error != 0) { 577 module_error("builtin module `%s' " 578 "failed to init", mi->mi_name); 579 kmem_free(mod, sizeof(*mod)); 580 return error; 581 } 582 if (mi->mi_class == MODULE_CLASS_SECMODEL) 583 secmodel_register(); 584 mod->mod_info = mi; 585 mod->mod_source = MODULE_SOURCE_KERNEL; 586 module_enqueue(mod); 587 return 0; 588 } 589 590 /* 591 * module_do_load: 592 * 593 * Helper routine: load a module from the file system, or one 594 * pushed by the boot loader. 595 */ 596 static int 597 module_do_load(const char *name, bool isdep, int flags, 598 prop_dictionary_t props, module_t **modp, modclass_t class, 599 bool autoload) 600 { 601 static TAILQ_HEAD(,module) pending = TAILQ_HEAD_INITIALIZER(pending); 602 static int depth; 603 const int maxdepth = 6; 604 modinfo_t *mi; 605 module_t *mod, *mod2; 606 prop_dictionary_t filedict; 607 char buf[MAXMODNAME]; 608 const char *s, *p; 609 int error; 610 size_t len; 611 612 KASSERT(mutex_owned(&module_lock)); 613 614 filedict = NULL; 615 error = 0; 616 617 /* 618 * Avoid recursing too far. 619 */ 620 if (++depth > maxdepth) { 621 module_error("too many required modules"); 622 depth--; 623 return EMLINK; 624 } 625 626 /* 627 * Load the module and link. Before going to the file system, 628 * scan the list of modules loaded by the boot loader. 629 */ 630 TAILQ_FOREACH(mod, &module_bootlist, mod_chain) { 631 if (strcmp(mod->mod_info->mi_name, name) == 0) { 632 TAILQ_REMOVE(&module_bootlist, mod, mod_chain); 633 break; 634 } 635 } 636 if (mod != NULL) { 637 TAILQ_INSERT_TAIL(&pending, mod, mod_chain); 638 } else { 639 /* 640 * If a requisite module, check to see if it is 641 * already present. 642 */ 643 if (isdep) { 644 TAILQ_FOREACH(mod, &module_list, mod_chain) { 645 if (strcmp(mod->mod_info->mi_name, name) == 0) { 646 break; 647 } 648 } 649 if (mod != NULL) { 650 if (modp != NULL) { 651 *modp = mod; 652 } 653 depth--; 654 return 0; 655 } 656 } 657 mod = kmem_zalloc(sizeof(*mod), KM_SLEEP); 658 if (mod == NULL) { 659 module_error("out of memory for `%s'", name); 660 depth--; 661 return ENOMEM; 662 } 663 664 error = module_load_vfs(name, flags, autoload, mod, &filedict); 665 if (error != 0) { 666 kmem_free(mod, sizeof(*mod)); 667 depth--; 668 return error; 669 } 670 mod->mod_source = MODULE_SOURCE_FILESYS; 671 TAILQ_INSERT_TAIL(&pending, mod, mod_chain); 672 673 error = module_fetch_info(mod); 674 if (error != 0) { 675 module_error("cannot fetch module info for `%s'", 676 name); 677 goto fail; 678 } 679 } 680 681 /* 682 * Check compatibility. 683 */ 684 mi = mod->mod_info; 685 if (strlen(mi->mi_name) >= MAXMODNAME) { 686 error = EINVAL; 687 module_error("module name `%s' too long", mi->mi_name); 688 goto fail; 689 } 690 if (!module_compatible(mi->mi_version, __NetBSD_Version__)) { 691 module_error("module built for `%d', system `%d'", 692 mi->mi_version, __NetBSD_Version__); 693 if ((flags & MODCTL_LOAD_FORCE) != 0) { 694 module_error("forced load, system may be unstable"); 695 } else { 696 error = EPROGMISMATCH; 697 goto fail; 698 } 699 } 700 701 /* 702 * If a specific kind of module was requested, ensure that we have 703 * a match. 704 */ 705 if (class != MODULE_CLASS_ANY && class != mi->mi_class) { 706 module_print("incompatible module class for `%s' (%d != %d)", 707 name, class, mi->mi_class); 708 error = ENOENT; 709 goto fail; 710 } 711 712 /* 713 * If loading a dependency, `name' is a plain module name. 714 * The name must match. 715 */ 716 if (isdep && strcmp(mi->mi_name, name) != 0) { 717 module_error("dependency name mismatch (`%s' != `%s')", 718 name, mi->mi_name); 719 error = ENOENT; 720 goto fail; 721 } 722 723 /* 724 * Check to see if the module is already loaded. If so, we may 725 * have been recursively called to handle a dependency, so be sure 726 * to set modp. 727 */ 728 if ((mod2 = module_lookup(mi->mi_name)) != NULL) { 729 if (modp != NULL) 730 *modp = mod2; 731 module_print("module `%s' already loaded", mi->mi_name); 732 error = EEXIST; 733 goto fail; 734 } 735 736 /* 737 * Block circular dependencies. 738 */ 739 TAILQ_FOREACH(mod2, &pending, mod_chain) { 740 if (mod == mod2) { 741 continue; 742 } 743 if (strcmp(mod2->mod_info->mi_name, mi->mi_name) == 0) { 744 error = EDEADLK; 745 module_error("circular dependency detected for `%s'", 746 mi->mi_name); 747 goto fail; 748 } 749 } 750 751 /* 752 * Now try to load any requisite modules. 753 */ 754 if (mi->mi_required != NULL) { 755 for (s = mi->mi_required; *s != '\0'; s = p) { 756 if (*s == ',') 757 s++; 758 p = s; 759 while (*p != '\0' && *p != ',') 760 p++; 761 len = p - s + 1; 762 if (len >= MAXMODNAME) { 763 error = EINVAL; 764 module_error("required module name `%s'" 765 " too long", mi->mi_required); 766 goto fail; 767 } 768 strlcpy(buf, s, len); 769 if (buf[0] == '\0') 770 break; 771 if (mod->mod_nrequired == MAXMODDEPS - 1) { 772 error = EINVAL; 773 module_error("too many required modules (%d)", 774 mod->mod_nrequired); 775 goto fail; 776 } 777 if (strcmp(buf, mi->mi_name) == 0) { 778 error = EDEADLK; 779 module_error("self-dependency detected for " 780 "`%s'", mi->mi_name); 781 goto fail; 782 } 783 error = module_do_load(buf, true, flags, NULL, 784 &mod->mod_required[mod->mod_nrequired++], 785 MODULE_CLASS_ANY, true); 786 if (error != 0) 787 goto fail; 788 } 789 } 790 791 /* 792 * We loaded all needed modules successfully: perform global 793 * relocations and initialize. 794 */ 795 error = kobj_affix(mod->mod_kobj, mi->mi_name); 796 if (error != 0) { 797 /* Cannot touch 'mi' as the module is now gone. */ 798 module_error("unable to affix module `%s'", name); 799 goto fail2; 800 } 801 802 if (filedict) { 803 if (!module_merge_dicts(filedict, props)) { 804 module_error("module properties failed"); 805 error = EINVAL; 806 goto fail; 807 } 808 } 809 KASSERT(module_active == NULL); 810 module_active = mod; 811 error = (*mi->mi_modcmd)(MODULE_CMD_INIT, filedict ? filedict : props); 812 module_active = NULL; 813 if (filedict) { 814 prop_object_release(filedict); 815 filedict = NULL; 816 } 817 if (error != 0) { 818 module_error("modcmd function returned error %d for `%s'", 819 error, mi->mi_name); 820 goto fail; 821 } 822 823 if (mi->mi_class == MODULE_CLASS_SECMODEL) 824 secmodel_register(); 825 826 /* 827 * Good, the module loaded successfully. Put it onto the 828 * list and add references to its requisite modules. 829 */ 830 TAILQ_REMOVE(&pending, mod, mod_chain); 831 module_enqueue(mod); 832 if (modp != NULL) { 833 *modp = mod; 834 } 835 if (autoload) { 836 /* 837 * Arrange to try unloading the module after 838 * a short delay. 839 */ 840 mod->mod_autotime = time_second + module_autotime; 841 module_thread_kick(); 842 } 843 depth--; 844 return 0; 845 846 fail: 847 kobj_unload(mod->mod_kobj); 848 fail2: 849 if (filedict != NULL) { 850 prop_object_release(filedict); 851 filedict = NULL; 852 } 853 TAILQ_REMOVE(&pending, mod, mod_chain); 854 kmem_free(mod, sizeof(*mod)); 855 depth--; 856 return error; 857 } 858 859 /* 860 * module_do_unload: 861 * 862 * Helper routine: do the dirty work of unloading a module. 863 */ 864 static int 865 module_do_unload(const char *name) 866 { 867 module_t *mod; 868 int error; 869 u_int i; 870 871 KASSERT(mutex_owned(&module_lock)); 872 873 mod = module_lookup(name); 874 if (mod == NULL) { 875 module_error("module `%s' not found", name); 876 return ENOENT; 877 } 878 if (mod->mod_refcnt != 0 || mod->mod_source == MODULE_SOURCE_KERNEL) { 879 module_print("module `%s' busy", name); 880 return EBUSY; 881 } 882 KASSERT(module_active == NULL); 883 module_active = mod; 884 error = (*mod->mod_info->mi_modcmd)(MODULE_CMD_FINI, NULL); 885 module_active = NULL; 886 if (error != 0) { 887 module_print("cannot unload module `%s' error=%d", name, 888 error); 889 return error; 890 } 891 if (mod->mod_info->mi_class == MODULE_CLASS_SECMODEL) 892 secmodel_deregister(); 893 module_count--; 894 TAILQ_REMOVE(&module_list, mod, mod_chain); 895 for (i = 0; i < mod->mod_nrequired; i++) { 896 mod->mod_required[i]->mod_refcnt--; 897 } 898 if (mod->mod_kobj != NULL) { 899 kobj_unload(mod->mod_kobj); 900 } 901 kmem_free(mod, sizeof(*mod)); 902 module_gen++; 903 904 return 0; 905 } 906 907 /* 908 * module_prime: 909 * 910 * Push a module loaded by the bootloader onto our internal 911 * list. 912 */ 913 int 914 module_prime(void *base, size_t size) 915 { 916 module_t *mod; 917 int error; 918 919 mod = kmem_zalloc(sizeof(*mod), KM_SLEEP); 920 if (mod == NULL) { 921 return ENOMEM; 922 } 923 mod->mod_source = MODULE_SOURCE_BOOT; 924 925 error = kobj_load_mem(&mod->mod_kobj, base, size); 926 if (error != 0) { 927 kmem_free(mod, sizeof(*mod)); 928 module_error("unable to load object pushed by boot loader"); 929 return error; 930 } 931 error = module_fetch_info(mod); 932 if (error != 0) { 933 kobj_unload(mod->mod_kobj); 934 kmem_free(mod, sizeof(*mod)); 935 module_error("unable to load object pushed by boot loader"); 936 return error; 937 } 938 939 TAILQ_INSERT_TAIL(&module_bootlist, mod, mod_chain); 940 941 return 0; 942 } 943 944 /* 945 * module_fetch_into: 946 * 947 * Fetch modinfo record from a loaded module. 948 */ 949 static int 950 module_fetch_info(module_t *mod) 951 { 952 int error; 953 void *addr; 954 size_t size; 955 956 /* 957 * Find module info record and check compatibility. 958 */ 959 error = kobj_find_section(mod->mod_kobj, "link_set_modules", 960 &addr, &size); 961 if (error != 0) { 962 module_error("`link_set_modules' section not present"); 963 return error; 964 } 965 if (size != sizeof(modinfo_t **)) { 966 module_error("`link_set_modules' section wrong size"); 967 return error; 968 } 969 mod->mod_info = *(modinfo_t **)addr; 970 971 return 0; 972 } 973 974 /* 975 * module_find_section: 976 * 977 * Allows a module that is being initialized to look up a section 978 * within its ELF object. 979 */ 980 int 981 module_find_section(const char *name, void **addr, size_t *size) 982 { 983 984 KASSERT(mutex_owned(&module_lock)); 985 KASSERT(module_active != NULL); 986 987 return kobj_find_section(module_active->mod_kobj, name, addr, size); 988 } 989 990 /* 991 * module_thread: 992 * 993 * Automatically unload modules. We try once to unload autoloaded 994 * modules after module_autotime seconds. If the system is under 995 * severe memory pressure, we'll try unloading all modules. 996 */ 997 static void 998 module_thread(void *cookie) 999 { 1000 module_t *mod, *next; 1001 modinfo_t *mi; 1002 int error; 1003 1004 for (;;) { 1005 mutex_enter(&module_lock); 1006 for (mod = TAILQ_FIRST(&module_list); mod != NULL; mod = next) { 1007 next = TAILQ_NEXT(mod, mod_chain); 1008 if (uvmexp.free < uvmexp.freemin) { 1009 module_thread_ticks = hz; 1010 } else if (mod->mod_autotime == 0) { 1011 continue; 1012 } else if (time_second < mod->mod_autotime) { 1013 module_thread_ticks = hz; 1014 continue; 1015 } else { 1016 mod->mod_autotime = 0; 1017 } 1018 /* 1019 * If this module wants to avoid autounload then 1020 * skip it. Some modules can ping-pong in and out 1021 * because their use is transient but often. 1022 * Example: exec_script. 1023 */ 1024 mi = mod->mod_info; 1025 error = (*mi->mi_modcmd)(MODULE_CMD_AUTOUNLOAD, NULL); 1026 if (error == 0 || error == ENOTTY) { 1027 (void)module_do_unload(mi->mi_name); 1028 } 1029 } 1030 mutex_exit(&module_lock); 1031 1032 mutex_enter(&module_thread_lock); 1033 (void)cv_timedwait(&module_thread_cv, &module_thread_lock, 1034 module_thread_ticks); 1035 module_thread_ticks = 0; 1036 mutex_exit(&module_thread_lock); 1037 } 1038 } 1039 1040 /* 1041 * module_thread: 1042 * 1043 * Kick the module thread into action, perhaps because the 1044 * system is low on memory. 1045 */ 1046 void 1047 module_thread_kick(void) 1048 { 1049 1050 mutex_enter(&module_thread_lock); 1051 module_thread_ticks = hz; 1052 cv_broadcast(&module_thread_cv); 1053 mutex_exit(&module_thread_lock); 1054 } 1055 1056 #ifdef DDB 1057 /* 1058 * module_whatis: 1059 * 1060 * Helper routine for DDB. 1061 */ 1062 void 1063 module_whatis(uintptr_t addr, void (*pr)(const char *, ...)) 1064 { 1065 module_t *mod; 1066 size_t msize; 1067 vaddr_t maddr; 1068 1069 TAILQ_FOREACH(mod, &module_list, mod_chain) { 1070 if (mod->mod_kobj == NULL) { 1071 continue; 1072 } 1073 if (kobj_stat(mod->mod_kobj, &maddr, &msize) != 0) 1074 continue; 1075 if (addr < maddr || addr >= maddr + msize) { 1076 continue; 1077 } 1078 (*pr)("%p is %p+%zu, in kernel module `%s'\n", 1079 (void *)addr, (void *)maddr, 1080 (size_t)(addr - maddr), mod->mod_info->mi_name); 1081 } 1082 } 1083 1084 /* 1085 * module_print_list: 1086 * 1087 * Helper routine for DDB. 1088 */ 1089 void 1090 module_print_list(void (*pr)(const char *, ...)) 1091 { 1092 const char *src; 1093 module_t *mod; 1094 size_t msize; 1095 vaddr_t maddr; 1096 1097 (*pr)("%16s %16s %8s %8s\n", "NAME", "TEXT/DATA", "SIZE", "SOURCE"); 1098 1099 TAILQ_FOREACH(mod, &module_list, mod_chain) { 1100 switch (mod->mod_source) { 1101 case MODULE_SOURCE_KERNEL: 1102 src = "builtin"; 1103 break; 1104 case MODULE_SOURCE_FILESYS: 1105 src = "filesys"; 1106 break; 1107 case MODULE_SOURCE_BOOT: 1108 src = "boot"; 1109 break; 1110 default: 1111 src = "unknown"; 1112 break; 1113 } 1114 if (mod->mod_kobj == NULL) { 1115 maddr = 0; 1116 msize = 0; 1117 } else if (kobj_stat(mod->mod_kobj, &maddr, &msize) != 0) 1118 continue; 1119 (*pr)("%16s %16lx %8ld %8s\n", mod->mod_info->mi_name, 1120 (long)maddr, (long)msize, src); 1121 } 1122 } 1123 #endif /* DDB */ 1124 1125 static bool 1126 module_merge_dicts(prop_dictionary_t existing_dict, 1127 const prop_dictionary_t new_dict) 1128 { 1129 prop_dictionary_keysym_t props_keysym; 1130 prop_object_iterator_t props_iter; 1131 prop_object_t props_obj; 1132 const char *props_key; 1133 bool error; 1134 1135 if (new_dict == NULL) { /* nothing to merge */ 1136 return true; 1137 } 1138 1139 error = false; 1140 props_iter = prop_dictionary_iterator(new_dict); 1141 if (props_iter == NULL) { 1142 return false; 1143 } 1144 1145 while ((props_obj = prop_object_iterator_next(props_iter)) != NULL) { 1146 props_keysym = (prop_dictionary_keysym_t)props_obj; 1147 props_key = prop_dictionary_keysym_cstring_nocopy(props_keysym); 1148 props_obj = prop_dictionary_get_keysym(new_dict, props_keysym); 1149 if ((props_obj == NULL) || !prop_dictionary_set(existing_dict, 1150 props_key, props_obj)) { 1151 error = true; 1152 goto out; 1153 } 1154 } 1155 error = false; 1156 1157 out: 1158 prop_object_iterator_release(props_iter); 1159 1160 return !error; 1161 } 1162