1 /* $NetBSD: kern_module.c,v 1.78 2011/04/17 05:16:28 mrg 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 1.78 2011/04/17 05:16:28 mrg 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/kthread.h> 55 #include <sys/sysctl.h> 56 #include <sys/lock.h> 57 58 #include <uvm/uvm_extern.h> 59 60 #include <machine/stdarg.h> 61 62 struct vm_map *module_map; 63 char *module_machine; 64 char module_base[MODULE_BASE_SIZE]; 65 66 struct modlist module_list = TAILQ_HEAD_INITIALIZER(module_list); 67 struct modlist module_builtins = TAILQ_HEAD_INITIALIZER(module_builtins); 68 static struct modlist module_bootlist = TAILQ_HEAD_INITIALIZER(module_bootlist); 69 70 static module_t *module_active; 71 static bool module_verbose_on; 72 static bool module_autoload_on = true; 73 u_int module_count; 74 u_int module_builtinlist; 75 u_int module_autotime = 10; 76 u_int module_gen = 1; 77 static kcondvar_t module_thread_cv; 78 static kmutex_t module_thread_lock; 79 static int module_thread_ticks; 80 int (*module_load_vfs_vec)(const char *, int, bool, module_t *, 81 prop_dictionary_t *) = (void *)eopnotsupp; 82 83 static kauth_listener_t module_listener; 84 85 /* Ensure that the kernel's link set isn't empty. */ 86 static modinfo_t module_dummy; 87 __link_set_add_rodata(modules, module_dummy); 88 89 static module_t *module_newmodule(modsrc_t); 90 static void module_require_force(module_t *); 91 static int module_do_load(const char *, bool, int, prop_dictionary_t, 92 module_t **, modclass_t class, bool); 93 static int module_do_unload(const char *, bool); 94 static int module_do_builtin(const char *, module_t **, prop_dictionary_t); 95 static int module_fetch_info(module_t *); 96 static void module_thread(void *); 97 98 static module_t *module_lookup(const char *); 99 static void module_enqueue(module_t *); 100 101 static bool module_merge_dicts(prop_dictionary_t, const prop_dictionary_t); 102 103 static void sysctl_module_setup(void); 104 105 /* 106 * module_error: 107 * 108 * Utility function: log an error. 109 */ 110 void 111 module_error(const char *fmt, ...) 112 { 113 va_list ap; 114 115 va_start(ap, fmt); 116 printf("WARNING: module error: "); 117 vprintf(fmt, ap); 118 printf("\n"); 119 va_end(ap); 120 } 121 122 /* 123 * module_print: 124 * 125 * Utility function: log verbose output. 126 */ 127 void 128 module_print(const char *fmt, ...) 129 { 130 va_list ap; 131 132 if (module_verbose_on) { 133 va_start(ap, fmt); 134 printf("DEBUG: module: "); 135 vprintf(fmt, ap); 136 printf("\n"); 137 va_end(ap); 138 } 139 } 140 141 static int 142 module_listener_cb(kauth_cred_t cred, kauth_action_t action, void *cookie, 143 void *arg0, void *arg1, void *arg2, void *arg3) 144 { 145 int result; 146 147 result = KAUTH_RESULT_DEFER; 148 149 if (action != KAUTH_SYSTEM_MODULE) 150 return result; 151 152 if ((uintptr_t)arg2 != 0) /* autoload */ 153 result = KAUTH_RESULT_ALLOW; 154 155 return result; 156 } 157 158 /* 159 * Allocate a new module_t 160 */ 161 static module_t * 162 module_newmodule(modsrc_t source) 163 { 164 module_t *mod; 165 166 mod = kmem_zalloc(sizeof(*mod), KM_SLEEP); 167 if (mod != NULL) { 168 mod->mod_source = source; 169 mod->mod_info = NULL; 170 mod->mod_flags = 0; 171 } 172 return mod; 173 } 174 175 /* 176 * Require the -f (force) flag to load a module 177 */ 178 static void 179 module_require_force(struct module *mod) 180 { 181 mod->mod_flags |= MODFLG_MUST_FORCE; 182 } 183 184 /* 185 * Add modules to the builtin list. This can done at boottime or 186 * at runtime if the module is linked into the kernel with an 187 * external linker. All or none of the input will be handled. 188 * Optionally, the modules can be initialized. If they are not 189 * initialized, module_init_class() or module_load() can be used 190 * later, but these are not guaranteed to give atomic results. 191 */ 192 int 193 module_builtin_add(modinfo_t *const *mip, size_t nmodinfo, bool init) 194 { 195 struct module **modp = NULL, *mod_iter; 196 int rv = 0, i, mipskip; 197 198 if (init) { 199 rv = kauth_authorize_system(kauth_cred_get(), 200 KAUTH_SYSTEM_MODULE, 0, (void *)(uintptr_t)MODCTL_LOAD, 201 (void *)(uintptr_t)1, NULL); 202 if (rv) { 203 return rv; 204 } 205 } 206 207 for (i = 0, mipskip = 0; i < nmodinfo; i++) { 208 if (mip[i] == &module_dummy) { 209 KASSERT(nmodinfo > 0); 210 nmodinfo--; 211 } 212 } 213 if (nmodinfo == 0) 214 return 0; 215 216 modp = kmem_zalloc(sizeof(*modp) * nmodinfo, KM_SLEEP); 217 for (i = 0, mipskip = 0; i < nmodinfo; i++) { 218 if (mip[i+mipskip] == &module_dummy) { 219 mipskip++; 220 continue; 221 } 222 modp[i] = module_newmodule(MODULE_SOURCE_KERNEL); 223 modp[i]->mod_info = mip[i+mipskip]; 224 } 225 kernconfig_lock(); 226 227 /* do this in three stages for error recovery and atomicity */ 228 229 /* first check for presence */ 230 for (i = 0; i < nmodinfo; i++) { 231 TAILQ_FOREACH(mod_iter, &module_builtins, mod_chain) { 232 if (strcmp(mod_iter->mod_info->mi_name, 233 modp[i]->mod_info->mi_name) == 0) 234 break; 235 } 236 if (mod_iter) { 237 rv = EEXIST; 238 goto out; 239 } 240 241 if (module_lookup(modp[i]->mod_info->mi_name) != NULL) { 242 rv = EEXIST; 243 goto out; 244 } 245 } 246 247 /* then add to list */ 248 for (i = 0; i < nmodinfo; i++) { 249 TAILQ_INSERT_TAIL(&module_builtins, modp[i], mod_chain); 250 module_builtinlist++; 251 } 252 253 /* finally, init (if required) */ 254 if (init) { 255 for (i = 0; i < nmodinfo; i++) { 256 rv = module_do_builtin(modp[i]->mod_info->mi_name, 257 NULL, NULL); 258 /* throw in the towel, recovery hard & not worth it */ 259 if (rv) 260 panic("builtin module \"%s\" init failed: %d", 261 modp[i]->mod_info->mi_name, rv); 262 } 263 } 264 265 out: 266 kernconfig_unlock(); 267 if (rv != 0) { 268 for (i = 0; i < nmodinfo; i++) { 269 if (modp[i]) 270 kmem_free(modp[i], sizeof(*modp[i])); 271 } 272 } 273 kmem_free(modp, sizeof(*modp) * nmodinfo); 274 return rv; 275 } 276 277 /* 278 * Optionally fini and remove builtin module from the kernel. 279 * Note: the module will now be unreachable except via mi && builtin_add. 280 */ 281 int 282 module_builtin_remove(modinfo_t *mi, bool fini) 283 { 284 struct module *mod; 285 int rv = 0; 286 287 if (fini) { 288 rv = kauth_authorize_system(kauth_cred_get(), 289 KAUTH_SYSTEM_MODULE, 0, (void *)(uintptr_t)MODCTL_UNLOAD, 290 NULL, NULL); 291 if (rv) 292 return rv; 293 294 kernconfig_lock(); 295 rv = module_do_unload(mi->mi_name, true); 296 if (rv) { 297 goto out; 298 } 299 } else { 300 kernconfig_lock(); 301 } 302 TAILQ_FOREACH(mod, &module_builtins, mod_chain) { 303 if (strcmp(mod->mod_info->mi_name, mi->mi_name) == 0) 304 break; 305 } 306 if (mod) { 307 TAILQ_REMOVE(&module_builtins, mod, mod_chain); 308 module_builtinlist--; 309 } else { 310 KASSERT(fini == false); 311 rv = ENOENT; 312 } 313 314 out: 315 kernconfig_unlock(); 316 return rv; 317 } 318 319 /* 320 * module_init: 321 * 322 * Initialize the module subsystem. 323 */ 324 void 325 module_init(void) 326 { 327 __link_set_decl(modules, modinfo_t); 328 extern struct vm_map *module_map; 329 modinfo_t *const *mip; 330 int rv; 331 332 if (module_map == NULL) { 333 module_map = kernel_map; 334 } 335 cv_init(&module_thread_cv, "mod_unld"); 336 mutex_init(&module_thread_lock, MUTEX_DEFAULT, IPL_NONE); 337 338 #ifdef MODULAR /* XXX */ 339 module_init_md(); 340 #endif 341 342 if (!module_machine) 343 module_machine = machine; 344 #if __NetBSD_Version__ / 1000000 % 100 == 99 /* -current */ 345 snprintf(module_base, sizeof(module_base), "/stand/%s/%s/modules", 346 module_machine, osrelease); 347 #else /* release */ 348 snprintf(module_base, sizeof(module_base), "/stand/%s/%d.%d/modules", 349 module_machine, __NetBSD_Version__ / 100000000, 350 __NetBSD_Version__ / 1000000 % 100); 351 #endif 352 353 module_listener = kauth_listen_scope(KAUTH_SCOPE_SYSTEM, 354 module_listener_cb, NULL); 355 356 __link_set_foreach(mip, modules) { 357 if ((rv = module_builtin_add(mip, 1, false)) != 0) 358 module_error("builtin %s failed: %d\n", 359 (*mip)->mi_name, rv); 360 } 361 362 sysctl_module_setup(); 363 } 364 365 /* 366 * module_start_unload_thread: 367 * 368 * Start the auto unload kthread. 369 */ 370 void 371 module_start_unload_thread(void) 372 { 373 int error; 374 375 error = kthread_create(PRI_VM, KTHREAD_MPSAFE, NULL, module_thread, 376 NULL, NULL, "modunload"); 377 if (error != 0) 378 panic("module_init: %d", error); 379 } 380 381 /* 382 * module_builtin_require_force 383 * 384 * Require MODCTL_MUST_FORCE to load any built-in modules that have 385 * not yet been initialized 386 */ 387 void 388 module_builtin_require_force(void) 389 { 390 module_t *mod; 391 392 kernconfig_lock(); 393 TAILQ_FOREACH(mod, &module_builtins, mod_chain) { 394 module_require_force(mod); 395 } 396 kernconfig_unlock(); 397 } 398 399 static struct sysctllog *module_sysctllog; 400 401 static void 402 sysctl_module_setup(void) 403 { 404 const struct sysctlnode *node = NULL; 405 406 sysctl_createv(&module_sysctllog, 0, NULL, NULL, 407 CTLFLAG_PERMANENT, 408 CTLTYPE_NODE, "kern", NULL, 409 NULL, 0, NULL, 0, 410 CTL_KERN, CTL_EOL); 411 sysctl_createv(&module_sysctllog, 0, NULL, &node, 412 CTLFLAG_PERMANENT, 413 CTLTYPE_NODE, "module", 414 SYSCTL_DESCR("Module options"), 415 NULL, 0, NULL, 0, 416 CTL_KERN, CTL_CREATE, CTL_EOL); 417 418 if (node == NULL) 419 return; 420 421 sysctl_createv(&module_sysctllog, 0, &node, NULL, 422 CTLFLAG_PERMANENT | CTLFLAG_READWRITE, 423 CTLTYPE_BOOL, "autoload", 424 SYSCTL_DESCR("Enable automatic load of modules"), 425 NULL, 0, &module_autoload_on, 0, 426 CTL_CREATE, CTL_EOL); 427 sysctl_createv(&module_sysctllog, 0, &node, NULL, 428 CTLFLAG_PERMANENT | CTLFLAG_READWRITE, 429 CTLTYPE_BOOL, "verbose", 430 SYSCTL_DESCR("Enable verbose output"), 431 NULL, 0, &module_verbose_on, 0, 432 CTL_CREATE, CTL_EOL); 433 } 434 435 /* 436 * module_init_class: 437 * 438 * Initialize all built-in and pre-loaded modules of the 439 * specified class. 440 */ 441 void 442 module_init_class(modclass_t class) 443 { 444 TAILQ_HEAD(, module) bi_fail = TAILQ_HEAD_INITIALIZER(bi_fail); 445 module_t *mod; 446 modinfo_t *mi; 447 448 kernconfig_lock(); 449 /* 450 * Builtins first. These will not depend on pre-loaded modules 451 * (because the kernel would not link). 452 */ 453 do { 454 TAILQ_FOREACH(mod, &module_builtins, mod_chain) { 455 mi = mod->mod_info; 456 if (class != MODULE_CLASS_ANY && class != mi->mi_class) 457 continue; 458 /* 459 * If initializing a builtin module fails, don't try 460 * to load it again. But keep it around and queue it 461 * on the builtins list after we're done with module 462 * init. Don't set it to MODFLG_MUST_FORCE in case a 463 * future attempt to initialize can be successful. 464 * (If the module has previously been set to 465 * MODFLG_MUST_FORCE, don't try to override that!) 466 */ 467 if (mod->mod_flags & MODFLG_MUST_FORCE || 468 module_do_builtin(mi->mi_name, NULL, NULL) != 0) { 469 TAILQ_REMOVE(&module_builtins, mod, mod_chain); 470 TAILQ_INSERT_TAIL(&bi_fail, mod, mod_chain); 471 } 472 break; 473 } 474 } while (mod != NULL); 475 476 /* 477 * Now preloaded modules. These will be pulled off the 478 * list as we call module_do_load(); 479 */ 480 do { 481 TAILQ_FOREACH(mod, &module_bootlist, mod_chain) { 482 mi = mod->mod_info; 483 if (class != MODULE_CLASS_ANY && class != mi->mi_class) 484 continue; 485 module_do_load(mi->mi_name, false, 0, NULL, NULL, 486 class, false); 487 break; 488 } 489 } while (mod != NULL); 490 491 /* return failed builtin modules to builtin list */ 492 while ((mod = TAILQ_FIRST(&bi_fail)) != NULL) { 493 TAILQ_REMOVE(&bi_fail, mod, mod_chain); 494 TAILQ_INSERT_TAIL(&module_builtins, mod, mod_chain); 495 } 496 497 kernconfig_unlock(); 498 } 499 500 /* 501 * module_compatible: 502 * 503 * Return true if the two supplied kernel versions are said to 504 * have the same binary interface for kernel code. The entire 505 * version is signficant for the development tree (-current), 506 * major and minor versions are significant for official 507 * releases of the system. 508 */ 509 bool 510 module_compatible(int v1, int v2) 511 { 512 513 #if __NetBSD_Version__ / 1000000 % 100 == 99 /* -current */ 514 return v1 == v2; 515 #else /* release */ 516 return abs(v1 - v2) < 10000; 517 #endif 518 } 519 520 /* 521 * module_load: 522 * 523 * Load a single module from the file system. 524 */ 525 int 526 module_load(const char *filename, int flags, prop_dictionary_t props, 527 modclass_t class) 528 { 529 int error; 530 531 /* Authorize. */ 532 error = kauth_authorize_system(kauth_cred_get(), KAUTH_SYSTEM_MODULE, 533 0, (void *)(uintptr_t)MODCTL_LOAD, NULL, NULL); 534 if (error != 0) { 535 return error; 536 } 537 538 kernconfig_lock(); 539 error = module_do_load(filename, false, flags, props, NULL, class, 540 false); 541 kernconfig_unlock(); 542 543 return error; 544 } 545 546 /* 547 * module_autoload: 548 * 549 * Load a single module from the file system, system initiated. 550 */ 551 int 552 module_autoload(const char *filename, modclass_t class) 553 { 554 int error; 555 556 kernconfig_lock(); 557 558 /* Nothing if the user has disabled it. */ 559 if (!module_autoload_on) { 560 kernconfig_unlock(); 561 return EPERM; 562 } 563 564 /* Disallow path separators and magic symlinks. */ 565 if (strchr(filename, '/') != NULL || strchr(filename, '@') != NULL || 566 strchr(filename, '.') != NULL) { 567 kernconfig_unlock(); 568 return EPERM; 569 } 570 571 /* Authorize. */ 572 error = kauth_authorize_system(kauth_cred_get(), KAUTH_SYSTEM_MODULE, 573 0, (void *)(uintptr_t)MODCTL_LOAD, (void *)(uintptr_t)1, NULL); 574 575 if (error == 0) 576 error = module_do_load(filename, false, 0, NULL, NULL, class, 577 true); 578 579 kernconfig_unlock(); 580 return error; 581 } 582 583 /* 584 * module_unload: 585 * 586 * Find and unload a module by name. 587 */ 588 int 589 module_unload(const char *name) 590 { 591 int error; 592 593 /* Authorize. */ 594 error = kauth_authorize_system(kauth_cred_get(), KAUTH_SYSTEM_MODULE, 595 0, (void *)(uintptr_t)MODCTL_UNLOAD, NULL, NULL); 596 if (error != 0) { 597 return error; 598 } 599 600 kernconfig_lock(); 601 error = module_do_unload(name, true); 602 kernconfig_unlock(); 603 604 return error; 605 } 606 607 /* 608 * module_lookup: 609 * 610 * Look up a module by name. 611 */ 612 module_t * 613 module_lookup(const char *name) 614 { 615 module_t *mod; 616 617 KASSERT(kernconfig_is_held()); 618 619 TAILQ_FOREACH(mod, &module_list, mod_chain) { 620 if (strcmp(mod->mod_info->mi_name, name) == 0) { 621 break; 622 } 623 } 624 625 return mod; 626 } 627 628 /* 629 * module_hold: 630 * 631 * Add a single reference to a module. It's the caller's 632 * responsibility to ensure that the reference is dropped 633 * later. 634 */ 635 int 636 module_hold(const char *name) 637 { 638 module_t *mod; 639 640 kernconfig_lock(); 641 mod = module_lookup(name); 642 if (mod == NULL) { 643 kernconfig_unlock(); 644 return ENOENT; 645 } 646 mod->mod_refcnt++; 647 kernconfig_unlock(); 648 649 return 0; 650 } 651 652 /* 653 * module_rele: 654 * 655 * Release a reference acquired with module_hold(). 656 */ 657 void 658 module_rele(const char *name) 659 { 660 module_t *mod; 661 662 kernconfig_lock(); 663 mod = module_lookup(name); 664 if (mod == NULL) { 665 kernconfig_unlock(); 666 panic("module_rele: gone"); 667 } 668 mod->mod_refcnt--; 669 kernconfig_unlock(); 670 } 671 672 /* 673 * module_enqueue: 674 * 675 * Put a module onto the global list and update counters. 676 */ 677 void 678 module_enqueue(module_t *mod) 679 { 680 int i; 681 682 KASSERT(kernconfig_is_held()); 683 684 /* 685 * If there are requisite modules, put at the head of the queue. 686 * This is so that autounload can unload requisite modules with 687 * only one pass through the queue. 688 */ 689 if (mod->mod_nrequired) { 690 TAILQ_INSERT_HEAD(&module_list, mod, mod_chain); 691 692 /* Add references to the requisite modules. */ 693 for (i = 0; i < mod->mod_nrequired; i++) { 694 KASSERT(mod->mod_required[i] != NULL); 695 mod->mod_required[i]->mod_refcnt++; 696 } 697 } else { 698 TAILQ_INSERT_TAIL(&module_list, mod, mod_chain); 699 } 700 module_count++; 701 module_gen++; 702 } 703 704 /* 705 * module_do_builtin: 706 * 707 * Initialize a module from the list of modules that are 708 * already linked into the kernel. 709 */ 710 static int 711 module_do_builtin(const char *name, module_t **modp, prop_dictionary_t props) 712 { 713 const char *p, *s; 714 char buf[MAXMODNAME]; 715 modinfo_t *mi = NULL; 716 module_t *mod, *mod2, *mod_loaded, *prev_active; 717 size_t len; 718 int error; 719 720 KASSERT(kernconfig_is_held()); 721 722 /* 723 * Search the list to see if we have a module by this name. 724 */ 725 TAILQ_FOREACH(mod, &module_builtins, mod_chain) { 726 if (strcmp(mod->mod_info->mi_name, name) == 0) { 727 mi = mod->mod_info; 728 break; 729 } 730 } 731 732 /* 733 * Check to see if already loaded. This might happen if we 734 * were already loaded as a dependency. 735 */ 736 if ((mod_loaded = module_lookup(name)) != NULL) { 737 KASSERT(mod == NULL); 738 if (modp) 739 *modp = mod_loaded; 740 return 0; 741 } 742 743 /* Note! This is from TAILQ, not immediate above */ 744 if (mi == NULL) { 745 /* 746 * XXX: We'd like to panic here, but currently in some 747 * cases (such as nfsserver + nfs), the dependee can be 748 * succesfully linked without the dependencies. 749 */ 750 module_error("can't find builtin dependency `%s'", name); 751 return ENOENT; 752 } 753 754 /* 755 * Initialize pre-requisites. 756 */ 757 if (mi->mi_required != NULL) { 758 for (s = mi->mi_required; *s != '\0'; s = p) { 759 if (*s == ',') 760 s++; 761 p = s; 762 while (*p != '\0' && *p != ',') 763 p++; 764 len = min(p - s + 1, sizeof(buf)); 765 strlcpy(buf, s, len); 766 if (buf[0] == '\0') 767 break; 768 if (mod->mod_nrequired == MAXMODDEPS - 1) { 769 module_error("too many required modules"); 770 return EINVAL; 771 } 772 error = module_do_builtin(buf, &mod2, NULL); 773 if (error != 0) { 774 return error; 775 } 776 mod->mod_required[mod->mod_nrequired++] = mod2; 777 } 778 } 779 780 /* 781 * Try to initialize the module. 782 */ 783 prev_active = module_active; 784 module_active = mod; 785 error = (*mi->mi_modcmd)(MODULE_CMD_INIT, props); 786 module_active = prev_active; 787 if (error != 0) { 788 module_error("builtin module `%s' " 789 "failed to init", mi->mi_name); 790 return error; 791 } 792 793 /* load always succeeds after this point */ 794 795 TAILQ_REMOVE(&module_builtins, mod, mod_chain); 796 module_builtinlist--; 797 if (modp != NULL) { 798 *modp = mod; 799 } 800 if (mi->mi_class == MODULE_CLASS_SECMODEL) 801 secmodel_register(); 802 module_enqueue(mod); 803 return 0; 804 } 805 806 /* 807 * module_do_load: 808 * 809 * Helper routine: load a module from the file system, or one 810 * pushed by the boot loader. 811 */ 812 static int 813 module_do_load(const char *name, bool isdep, int flags, 814 prop_dictionary_t props, module_t **modp, modclass_t class, 815 bool autoload) 816 { 817 #define MODULE_MAX_DEPTH 6 818 819 TAILQ_HEAD(pending_t, module); 820 static int depth = 0; 821 static struct pending_t *pending_lists[MODULE_MAX_DEPTH]; 822 struct pending_t *pending; 823 struct pending_t new_pending = TAILQ_HEAD_INITIALIZER(new_pending); 824 modinfo_t *mi; 825 module_t *mod, *mod2, *prev_active; 826 prop_dictionary_t filedict; 827 char buf[MAXMODNAME]; 828 const char *s, *p; 829 int error; 830 size_t len; 831 832 KASSERT(kernconfig_is_held()); 833 834 filedict = NULL; 835 error = 0; 836 837 /* 838 * Avoid recursing too far. 839 */ 840 if (++depth > MODULE_MAX_DEPTH) { 841 module_error("recursion too deep"); 842 depth--; 843 return EMLINK; 844 } 845 846 /* 847 * Set up the pending list for this depth. If this is a 848 * recursive entry, then use same list as for outer call, 849 * else use the locally allocated list. In either case, 850 * remember which one we're using. 851 */ 852 if (isdep) { 853 KASSERT(depth > 1); 854 pending = pending_lists[depth - 2]; 855 } else 856 pending = &new_pending; 857 pending_lists[depth - 1] = pending; 858 859 /* 860 * Search the list of disabled builtins first. 861 */ 862 TAILQ_FOREACH(mod, &module_builtins, mod_chain) { 863 if (strcmp(mod->mod_info->mi_name, name) == 0) { 864 break; 865 } 866 } 867 if (mod) { 868 if ((mod->mod_flags & MODFLG_MUST_FORCE) && 869 (flags & MODCTL_LOAD_FORCE) == 0) { 870 if (!autoload) { 871 module_error("use -f to reinstate " 872 "builtin module \"%s\"", name); 873 } 874 depth--; 875 return EPERM; 876 } else { 877 error = module_do_builtin(name, NULL, props); 878 depth--; 879 return error; 880 } 881 } 882 883 /* 884 * Load the module and link. Before going to the file system, 885 * scan the list of modules loaded by the boot loader. 886 */ 887 TAILQ_FOREACH(mod, &module_bootlist, mod_chain) { 888 if (strcmp(mod->mod_info->mi_name, name) == 0) { 889 TAILQ_REMOVE(&module_bootlist, mod, mod_chain); 890 break; 891 } 892 } 893 if (mod != NULL) { 894 TAILQ_INSERT_TAIL(pending, mod, mod_chain); 895 } else { 896 /* 897 * If a requisite module, check to see if it is 898 * already present. 899 */ 900 if (isdep) { 901 mod = module_lookup(name); 902 if (mod != NULL) { 903 if (modp != NULL) { 904 *modp = mod; 905 } 906 depth--; 907 return 0; 908 } 909 } 910 mod = module_newmodule(MODULE_SOURCE_FILESYS); 911 if (mod == NULL) { 912 module_error("out of memory for `%s'", name); 913 depth--; 914 return ENOMEM; 915 } 916 917 error = module_load_vfs_vec(name, flags, autoload, mod, 918 &filedict); 919 if (error != 0) { 920 kmem_free(mod, sizeof(*mod)); 921 depth--; 922 return error; 923 } 924 TAILQ_INSERT_TAIL(pending, mod, mod_chain); 925 926 error = module_fetch_info(mod); 927 if (error != 0) { 928 module_error("cannot fetch module info for `%s'", 929 name); 930 goto fail; 931 } 932 } 933 934 /* 935 * Check compatibility. 936 */ 937 mi = mod->mod_info; 938 if (strlen(mi->mi_name) >= MAXMODNAME) { 939 error = EINVAL; 940 module_error("module name `%s' too long", mi->mi_name); 941 goto fail; 942 } 943 if (!module_compatible(mi->mi_version, __NetBSD_Version__)) { 944 module_error("module built for `%d', system `%d'", 945 mi->mi_version, __NetBSD_Version__); 946 if ((flags & MODCTL_LOAD_FORCE) != 0) { 947 module_error("forced load, system may be unstable"); 948 } else { 949 error = EPROGMISMATCH; 950 goto fail; 951 } 952 } 953 954 /* 955 * If a specific kind of module was requested, ensure that we have 956 * a match. 957 */ 958 if (class != MODULE_CLASS_ANY && class != mi->mi_class) { 959 module_print("incompatible module class for `%s' (%d != %d)", 960 name, class, mi->mi_class); 961 error = ENOENT; 962 goto fail; 963 } 964 965 /* 966 * If loading a dependency, `name' is a plain module name. 967 * The name must match. 968 */ 969 if (isdep && strcmp(mi->mi_name, name) != 0) { 970 module_error("dependency name mismatch (`%s' != `%s')", 971 name, mi->mi_name); 972 error = ENOENT; 973 goto fail; 974 } 975 976 /* 977 * Check to see if the module is already loaded. If so, we may 978 * have been recursively called to handle a dependency, so be sure 979 * to set modp. 980 */ 981 if ((mod2 = module_lookup(mi->mi_name)) != NULL) { 982 if (modp != NULL) 983 *modp = mod2; 984 module_print("module `%s' already loaded", mi->mi_name); 985 error = EEXIST; 986 goto fail; 987 } 988 989 /* 990 * Block circular dependencies. 991 */ 992 TAILQ_FOREACH(mod2, pending, mod_chain) { 993 if (mod == mod2) { 994 continue; 995 } 996 if (strcmp(mod2->mod_info->mi_name, mi->mi_name) == 0) { 997 error = EDEADLK; 998 module_error("circular dependency detected for `%s'", 999 mi->mi_name); 1000 goto fail; 1001 } 1002 } 1003 1004 /* 1005 * Now try to load any requisite modules. 1006 */ 1007 if (mi->mi_required != NULL) { 1008 for (s = mi->mi_required; *s != '\0'; s = p) { 1009 if (*s == ',') 1010 s++; 1011 p = s; 1012 while (*p != '\0' && *p != ',') 1013 p++; 1014 len = p - s + 1; 1015 if (len >= MAXMODNAME) { 1016 error = EINVAL; 1017 module_error("required module name `%s'" 1018 " too long", mi->mi_required); 1019 goto fail; 1020 } 1021 strlcpy(buf, s, len); 1022 if (buf[0] == '\0') 1023 break; 1024 if (mod->mod_nrequired == MAXMODDEPS - 1) { 1025 error = EINVAL; 1026 module_error("too many required modules (%d)", 1027 mod->mod_nrequired); 1028 goto fail; 1029 } 1030 if (strcmp(buf, mi->mi_name) == 0) { 1031 error = EDEADLK; 1032 module_error("self-dependency detected for " 1033 "`%s'", mi->mi_name); 1034 goto fail; 1035 } 1036 error = module_do_load(buf, true, flags, NULL, 1037 &mod->mod_required[mod->mod_nrequired++], 1038 MODULE_CLASS_ANY, true); 1039 if (error != 0) 1040 goto fail; 1041 } 1042 } 1043 1044 /* 1045 * We loaded all needed modules successfully: perform global 1046 * relocations and initialize. 1047 */ 1048 error = kobj_affix(mod->mod_kobj, mi->mi_name); 1049 if (error != 0) { 1050 /* Cannot touch 'mi' as the module is now gone. */ 1051 module_error("unable to affix module `%s'", name); 1052 goto fail2; 1053 } 1054 1055 if (filedict) { 1056 if (!module_merge_dicts(filedict, props)) { 1057 module_error("module properties failed"); 1058 error = EINVAL; 1059 goto fail; 1060 } 1061 } 1062 prev_active = module_active; 1063 module_active = mod; 1064 error = (*mi->mi_modcmd)(MODULE_CMD_INIT, filedict ? filedict : props); 1065 module_active = prev_active; 1066 if (filedict) { 1067 prop_object_release(filedict); 1068 filedict = NULL; 1069 } 1070 if (error != 0) { 1071 module_error("modcmd function returned error %d for `%s'", 1072 error, mi->mi_name); 1073 goto fail; 1074 } 1075 1076 if (mi->mi_class == MODULE_CLASS_SECMODEL) 1077 secmodel_register(); 1078 1079 /* 1080 * Good, the module loaded successfully. Put it onto the 1081 * list and add references to its requisite modules. 1082 */ 1083 TAILQ_REMOVE(pending, mod, mod_chain); 1084 module_enqueue(mod); 1085 if (modp != NULL) { 1086 *modp = mod; 1087 } 1088 if (autoload) { 1089 /* 1090 * Arrange to try unloading the module after 1091 * a short delay. 1092 */ 1093 mod->mod_autotime = time_second + module_autotime; 1094 module_thread_kick(); 1095 } 1096 depth--; 1097 return 0; 1098 1099 fail: 1100 kobj_unload(mod->mod_kobj); 1101 fail2: 1102 if (filedict != NULL) { 1103 prop_object_release(filedict); 1104 filedict = NULL; 1105 } 1106 TAILQ_REMOVE(pending, mod, mod_chain); 1107 kmem_free(mod, sizeof(*mod)); 1108 depth--; 1109 return error; 1110 } 1111 1112 /* 1113 * module_do_unload: 1114 * 1115 * Helper routine: do the dirty work of unloading a module. 1116 */ 1117 static int 1118 module_do_unload(const char *name, bool load_requires_force) 1119 { 1120 module_t *mod, *prev_active; 1121 int error; 1122 u_int i; 1123 1124 KASSERT(kernconfig_is_held()); 1125 1126 mod = module_lookup(name); 1127 if (mod == NULL) { 1128 module_error("module `%s' not found", name); 1129 return ENOENT; 1130 } 1131 if (mod->mod_refcnt != 0) { 1132 module_print("module `%s' busy", name); 1133 return EBUSY; 1134 } 1135 1136 /* 1137 * Builtin secmodels are there to stay. 1138 */ 1139 if (mod->mod_source == MODULE_SOURCE_KERNEL && 1140 mod->mod_info->mi_class == MODULE_CLASS_SECMODEL) { 1141 return EPERM; 1142 } 1143 1144 prev_active = module_active; 1145 module_active = mod; 1146 error = (*mod->mod_info->mi_modcmd)(MODULE_CMD_FINI, NULL); 1147 module_active = prev_active; 1148 if (error != 0) { 1149 module_print("cannot unload module `%s' error=%d", name, 1150 error); 1151 return error; 1152 } 1153 if (mod->mod_info->mi_class == MODULE_CLASS_SECMODEL) 1154 secmodel_deregister(); 1155 module_count--; 1156 TAILQ_REMOVE(&module_list, mod, mod_chain); 1157 for (i = 0; i < mod->mod_nrequired; i++) { 1158 mod->mod_required[i]->mod_refcnt--; 1159 } 1160 if (mod->mod_kobj != NULL) { 1161 kobj_unload(mod->mod_kobj); 1162 } 1163 if (mod->mod_source == MODULE_SOURCE_KERNEL) { 1164 mod->mod_nrequired = 0; /* will be re-parsed */ 1165 if (load_requires_force) 1166 module_require_force(mod); 1167 TAILQ_INSERT_TAIL(&module_builtins, mod, mod_chain); 1168 module_builtinlist++; 1169 } else { 1170 kmem_free(mod, sizeof(*mod)); 1171 } 1172 module_gen++; 1173 1174 return 0; 1175 } 1176 1177 /* 1178 * module_prime: 1179 * 1180 * Push a module loaded by the bootloader onto our internal 1181 * list. 1182 */ 1183 int 1184 module_prime(void *base, size_t size) 1185 { 1186 module_t *mod; 1187 int error; 1188 1189 mod = module_newmodule(MODULE_SOURCE_BOOT); 1190 if (mod == NULL) { 1191 return ENOMEM; 1192 } 1193 1194 error = kobj_load_mem(&mod->mod_kobj, base, size); 1195 if (error != 0) { 1196 kmem_free(mod, sizeof(*mod)); 1197 module_error("unable to load object pushed by boot loader"); 1198 return error; 1199 } 1200 error = module_fetch_info(mod); 1201 if (error != 0) { 1202 kobj_unload(mod->mod_kobj); 1203 kmem_free(mod, sizeof(*mod)); 1204 module_error("unable to load object pushed by boot loader"); 1205 return error; 1206 } 1207 1208 TAILQ_INSERT_TAIL(&module_bootlist, mod, mod_chain); 1209 1210 return 0; 1211 } 1212 1213 /* 1214 * module_fetch_into: 1215 * 1216 * Fetch modinfo record from a loaded module. 1217 */ 1218 static int 1219 module_fetch_info(module_t *mod) 1220 { 1221 int error; 1222 void *addr; 1223 size_t size; 1224 1225 /* 1226 * Find module info record and check compatibility. 1227 */ 1228 error = kobj_find_section(mod->mod_kobj, "link_set_modules", 1229 &addr, &size); 1230 if (error != 0) { 1231 module_error("`link_set_modules' section not present"); 1232 return error; 1233 } 1234 if (size != sizeof(modinfo_t **)) { 1235 module_error("`link_set_modules' section wrong size"); 1236 return error; 1237 } 1238 mod->mod_info = *(modinfo_t **)addr; 1239 1240 return 0; 1241 } 1242 1243 /* 1244 * module_find_section: 1245 * 1246 * Allows a module that is being initialized to look up a section 1247 * within its ELF object. 1248 */ 1249 int 1250 module_find_section(const char *name, void **addr, size_t *size) 1251 { 1252 1253 KASSERT(kernconfig_is_held()); 1254 KASSERT(module_active != NULL); 1255 1256 return kobj_find_section(module_active->mod_kobj, name, addr, size); 1257 } 1258 1259 /* 1260 * module_thread: 1261 * 1262 * Automatically unload modules. We try once to unload autoloaded 1263 * modules after module_autotime seconds. If the system is under 1264 * severe memory pressure, we'll try unloading all modules. 1265 */ 1266 static void 1267 module_thread(void *cookie) 1268 { 1269 module_t *mod, *next; 1270 modinfo_t *mi; 1271 int error; 1272 1273 for (;;) { 1274 kernconfig_lock(); 1275 for (mod = TAILQ_FIRST(&module_list); mod != NULL; mod = next) { 1276 next = TAILQ_NEXT(mod, mod_chain); 1277 if (mod->mod_source == MODULE_SOURCE_KERNEL) 1278 continue; 1279 if (uvmexp.free < uvmexp.freemin) { 1280 module_thread_ticks = hz; 1281 } else if (mod->mod_autotime == 0) { 1282 continue; 1283 } else if (time_second < mod->mod_autotime) { 1284 module_thread_ticks = hz; 1285 continue; 1286 } else { 1287 mod->mod_autotime = 0; 1288 } 1289 /* 1290 * If this module wants to avoid autounload then 1291 * skip it. Some modules can ping-pong in and out 1292 * because their use is transient but often. 1293 * Example: exec_script. 1294 */ 1295 mi = mod->mod_info; 1296 error = (*mi->mi_modcmd)(MODULE_CMD_AUTOUNLOAD, NULL); 1297 if (error == 0 || error == ENOTTY) { 1298 (void)module_do_unload(mi->mi_name, false); 1299 } 1300 } 1301 kernconfig_unlock(); 1302 1303 mutex_enter(&module_thread_lock); 1304 (void)cv_timedwait(&module_thread_cv, &module_thread_lock, 1305 module_thread_ticks); 1306 module_thread_ticks = 0; 1307 mutex_exit(&module_thread_lock); 1308 } 1309 } 1310 1311 /* 1312 * module_thread: 1313 * 1314 * Kick the module thread into action, perhaps because the 1315 * system is low on memory. 1316 */ 1317 void 1318 module_thread_kick(void) 1319 { 1320 1321 mutex_enter(&module_thread_lock); 1322 module_thread_ticks = hz; 1323 cv_broadcast(&module_thread_cv); 1324 mutex_exit(&module_thread_lock); 1325 } 1326 1327 #ifdef DDB 1328 /* 1329 * module_whatis: 1330 * 1331 * Helper routine for DDB. 1332 */ 1333 void 1334 module_whatis(uintptr_t addr, void (*pr)(const char *, ...)) 1335 { 1336 module_t *mod; 1337 size_t msize; 1338 vaddr_t maddr; 1339 1340 TAILQ_FOREACH(mod, &module_list, mod_chain) { 1341 if (mod->mod_kobj == NULL) { 1342 continue; 1343 } 1344 if (kobj_stat(mod->mod_kobj, &maddr, &msize) != 0) 1345 continue; 1346 if (addr < maddr || addr >= maddr + msize) { 1347 continue; 1348 } 1349 (*pr)("%p is %p+%zu, in kernel module `%s'\n", 1350 (void *)addr, (void *)maddr, 1351 (size_t)(addr - maddr), mod->mod_info->mi_name); 1352 } 1353 } 1354 1355 /* 1356 * module_print_list: 1357 * 1358 * Helper routine for DDB. 1359 */ 1360 void 1361 module_print_list(void (*pr)(const char *, ...)) 1362 { 1363 const char *src; 1364 module_t *mod; 1365 size_t msize; 1366 vaddr_t maddr; 1367 1368 (*pr)("%16s %16s %8s %8s\n", "NAME", "TEXT/DATA", "SIZE", "SOURCE"); 1369 1370 TAILQ_FOREACH(mod, &module_list, mod_chain) { 1371 switch (mod->mod_source) { 1372 case MODULE_SOURCE_KERNEL: 1373 src = "builtin"; 1374 break; 1375 case MODULE_SOURCE_FILESYS: 1376 src = "filesys"; 1377 break; 1378 case MODULE_SOURCE_BOOT: 1379 src = "boot"; 1380 break; 1381 default: 1382 src = "unknown"; 1383 break; 1384 } 1385 if (mod->mod_kobj == NULL) { 1386 maddr = 0; 1387 msize = 0; 1388 } else if (kobj_stat(mod->mod_kobj, &maddr, &msize) != 0) 1389 continue; 1390 (*pr)("%16s %16lx %8ld %8s\n", mod->mod_info->mi_name, 1391 (long)maddr, (long)msize, src); 1392 } 1393 } 1394 #endif /* DDB */ 1395 1396 static bool 1397 module_merge_dicts(prop_dictionary_t existing_dict, 1398 const prop_dictionary_t new_dict) 1399 { 1400 prop_dictionary_keysym_t props_keysym; 1401 prop_object_iterator_t props_iter; 1402 prop_object_t props_obj; 1403 const char *props_key; 1404 bool error; 1405 1406 if (new_dict == NULL) { /* nothing to merge */ 1407 return true; 1408 } 1409 1410 error = false; 1411 props_iter = prop_dictionary_iterator(new_dict); 1412 if (props_iter == NULL) { 1413 return false; 1414 } 1415 1416 while ((props_obj = prop_object_iterator_next(props_iter)) != NULL) { 1417 props_keysym = (prop_dictionary_keysym_t)props_obj; 1418 props_key = prop_dictionary_keysym_cstring_nocopy(props_keysym); 1419 props_obj = prop_dictionary_get_keysym(new_dict, props_keysym); 1420 if ((props_obj == NULL) || !prop_dictionary_set(existing_dict, 1421 props_key, props_obj)) { 1422 error = true; 1423 goto out; 1424 } 1425 } 1426 error = false; 1427 1428 out: 1429 prop_object_iterator_release(props_iter); 1430 1431 return !error; 1432 } 1433