1 /* $NetBSD: kern_module.c,v 1.60 2010/03/05 20:10:05 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 1.60 2010/03/05 20:10:05 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_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 int module_verbose_on; 72 static int module_autoload_on = 1; 73 u_int module_count; 74 u_int module_builtinlist; 75 kmutex_t module_lock; 76 u_int module_autotime = 10; 77 u_int module_gen = 1; 78 static kcondvar_t module_thread_cv; 79 static kmutex_t module_thread_lock; 80 static int module_thread_ticks; 81 82 static kauth_listener_t module_listener; 83 84 /* Ensure that the kernel's link set isn't empty. */ 85 static modinfo_t module_dummy; 86 __link_set_add_rodata(modules, module_dummy); 87 88 static int module_do_load(const char *, bool, int, prop_dictionary_t, 89 module_t **, modclass_t class, bool); 90 static int module_do_unload(const char *); 91 static int module_do_builtin(const char *, module_t **); 92 static int module_fetch_info(module_t *); 93 static void module_thread(void *); 94 95 static module_t *module_lookup(const char *); 96 static void module_enqueue(module_t *); 97 98 static bool module_merge_dicts(prop_dictionary_t, const prop_dictionary_t); 99 100 int module_eopnotsupp(void); 101 102 int 103 module_eopnotsupp(void) 104 { 105 106 return EOPNOTSUPP; 107 } 108 __weak_alias(module_load_vfs,module_eopnotsupp); 109 110 /* 111 * module_error: 112 * 113 * Utility function: log an error. 114 */ 115 void 116 module_error(const char *fmt, ...) 117 { 118 va_list ap; 119 120 va_start(ap, fmt); 121 printf("WARNING: module error: "); 122 vprintf(fmt, ap); 123 printf("\n"); 124 va_end(ap); 125 } 126 127 /* 128 * module_print: 129 * 130 * Utility function: log verbose output. 131 */ 132 void 133 module_print(const char *fmt, ...) 134 { 135 va_list ap; 136 137 if (module_verbose_on) { 138 va_start(ap, fmt); 139 printf("DEBUG: module: "); 140 vprintf(fmt, ap); 141 printf("\n"); 142 va_end(ap); 143 } 144 } 145 146 static int 147 module_listener_cb(kauth_cred_t cred, kauth_action_t action, void *cookie, 148 void *arg0, void *arg1, void *arg2, void *arg3) 149 { 150 int result; 151 152 result = KAUTH_RESULT_DEFER; 153 154 if (action != KAUTH_SYSTEM_MODULE) 155 return result; 156 157 if ((uintptr_t)arg2 != 0) /* autoload */ 158 result = KAUTH_RESULT_ALLOW; 159 160 return result; 161 } 162 163 /* 164 * Add modules to the builtin list. This can done at boottime or 165 * at runtime if the module is linked into the kernel with an 166 * external linker. All or none of the input will be handled. 167 * Optionally, the modules can be initialized. If they are not 168 * initialized, module_init_class() or module_load() can be used 169 * later, but these are not guaranteed to give atomic results. 170 */ 171 int 172 module_builtin_add(modinfo_t *const *mip, size_t nmodinfo, bool init) 173 { 174 struct module **modp = NULL, *mod_iter; 175 int rv = 0, i, mipskip; 176 177 if (init) { 178 rv = kauth_authorize_system(kauth_cred_get(), 179 KAUTH_SYSTEM_MODULE, 0, (void *)(uintptr_t)MODCTL_LOAD, 180 (void *)(uintptr_t)1, NULL); 181 if (rv) { 182 return rv; 183 } 184 } 185 186 for (i = 0, mipskip = 0; i < nmodinfo; i++) { 187 if (mip[i] == &module_dummy) { 188 KASSERT(nmodinfo > 0); 189 nmodinfo--; 190 } 191 } 192 if (nmodinfo == 0) 193 return 0; 194 195 modp = kmem_zalloc(sizeof(*modp) * nmodinfo, KM_SLEEP); 196 for (i = 0, mipskip = 0; i < nmodinfo; i++) { 197 if (mip[i+mipskip] == &module_dummy) { 198 mipskip++; 199 continue; 200 } 201 modp[i] = kmem_zalloc(sizeof(*modp[i]), KM_SLEEP); 202 modp[i]->mod_info = mip[i+mipskip]; 203 modp[i]->mod_source = MODULE_SOURCE_KERNEL; 204 } 205 mutex_enter(&module_lock); 206 207 /* do this in three stages for error recovery and atomicity */ 208 209 /* first check for presence */ 210 for (i = 0; i < nmodinfo; i++) { 211 TAILQ_FOREACH(mod_iter, &module_builtins, mod_chain) { 212 if (strcmp(mod_iter->mod_info->mi_name, 213 modp[i]->mod_info->mi_name) == 0) 214 break; 215 } 216 if (mod_iter) { 217 rv = EEXIST; 218 goto out; 219 } 220 221 if (module_lookup(modp[i]->mod_info->mi_name) != NULL) { 222 rv = EEXIST; 223 goto out; 224 } 225 } 226 227 /* then add to list */ 228 for (i = 0; i < nmodinfo; i++) { 229 TAILQ_INSERT_TAIL(&module_builtins, modp[i], mod_chain); 230 module_builtinlist++; 231 } 232 233 /* finally, init (if required) */ 234 if (init) { 235 for (i = 0; i < nmodinfo; i++) { 236 rv = module_do_builtin(modp[i]->mod_info->mi_name,NULL); 237 /* throw in the towel, recovery hard & not worth it */ 238 if (rv) 239 panic("builtin module \"%s\" init failed: %d", 240 modp[i]->mod_info->mi_name, rv); 241 } 242 } 243 244 out: 245 mutex_exit(&module_lock); 246 if (rv != 0) { 247 for (i = 0; i < nmodinfo; i++) { 248 if (modp[i]) 249 kmem_free(modp[i], sizeof(*modp[i])); 250 } 251 } 252 kmem_free(modp, sizeof(*modp) * nmodinfo); 253 return rv; 254 } 255 256 /* 257 * Optionally fini and remove builtin module from the kernel. 258 * Note: the module will now be unreachable except via mi && builtin_add. 259 */ 260 int 261 module_builtin_remove(modinfo_t *mi, bool fini) 262 { 263 struct module *mod; 264 int rv = 0; 265 266 if (fini) { 267 rv = kauth_authorize_system(kauth_cred_get(), 268 KAUTH_SYSTEM_MODULE, 0, (void *)(uintptr_t)MODCTL_UNLOAD, 269 NULL, NULL); 270 if (rv) 271 return rv; 272 273 mutex_enter(&module_lock); 274 rv = module_do_unload(mi->mi_name); 275 if (rv) { 276 goto out; 277 } 278 } else { 279 mutex_enter(&module_lock); 280 } 281 TAILQ_FOREACH(mod, &module_builtins, mod_chain) { 282 if (strcmp(mod->mod_info->mi_name, mi->mi_name) == 0) 283 break; 284 } 285 if (mod) { 286 TAILQ_REMOVE(&module_builtins, mod, mod_chain); 287 module_builtinlist--; 288 } else { 289 KASSERT(fini == false); 290 rv = ENOENT; 291 } 292 293 out: 294 mutex_exit(&module_lock); 295 return rv; 296 } 297 298 /* 299 * module_init: 300 * 301 * Initialize the module subsystem. 302 */ 303 void 304 module_init(void) 305 { 306 __link_set_decl(modules, modinfo_t); 307 extern struct vm_map *module_map; 308 modinfo_t *const *mip; 309 int rv; 310 311 if (module_map == NULL) { 312 module_map = kernel_map; 313 } 314 mutex_init(&module_lock, MUTEX_DEFAULT, IPL_NONE); 315 cv_init(&module_thread_cv, "modunload"); 316 mutex_init(&module_thread_lock, MUTEX_DEFAULT, IPL_NONE); 317 #ifdef MODULAR /* XXX */ 318 module_init_md(); 319 #endif 320 321 #if __NetBSD_Version__ / 1000000 % 100 == 99 /* -current */ 322 snprintf(module_base, sizeof(module_base), "/stand/%s/%s/modules", 323 machine, osrelease); 324 #else /* release */ 325 snprintf(module_base, sizeof(module_base), "/stand/%s/%d.%d/modules", 326 machine, __NetBSD_Version__ / 100000000, 327 __NetBSD_Version__ / 1000000 % 100); 328 #endif 329 330 module_listener = kauth_listen_scope(KAUTH_SCOPE_SYSTEM, 331 module_listener_cb, NULL); 332 333 __link_set_foreach(mip, modules) { 334 if ((rv = module_builtin_add(mip, 1, false) != 0)) 335 module_error("builtin %s failed: %d\n", 336 (*mip)->mi_name, rv); 337 } 338 } 339 340 /* 341 * module_init2: 342 * 343 * Start the auto unload kthread. 344 */ 345 void 346 module_init2(void) 347 { 348 int error; 349 350 error = kthread_create(PRI_VM, KTHREAD_MPSAFE, NULL, module_thread, 351 NULL, NULL, "modunload"); 352 if (error != 0) 353 panic("module_init: %d", error); 354 } 355 356 SYSCTL_SETUP(sysctl_module_setup, "sysctl module setup") 357 { 358 const struct sysctlnode *node = NULL; 359 360 sysctl_createv(clog, 0, NULL, NULL, 361 CTLFLAG_PERMANENT, 362 CTLTYPE_NODE, "kern", NULL, 363 NULL, 0, NULL, 0, 364 CTL_KERN, CTL_EOL); 365 sysctl_createv(clog, 0, NULL, &node, 366 CTLFLAG_PERMANENT, 367 CTLTYPE_NODE, "module", 368 SYSCTL_DESCR("Module options"), 369 NULL, 0, NULL, 0, 370 CTL_KERN, CTL_CREATE, CTL_EOL); 371 372 if (node == NULL) 373 return; 374 375 sysctl_createv(clog, 0, &node, NULL, 376 CTLFLAG_PERMANENT | CTLFLAG_READWRITE, 377 CTLTYPE_INT, "autoload", 378 SYSCTL_DESCR("Enable automatic load of modules"), 379 NULL, 0, &module_autoload_on, 0, 380 CTL_CREATE, CTL_EOL); 381 sysctl_createv(clog, 0, &node, NULL, 382 CTLFLAG_PERMANENT | CTLFLAG_READWRITE, 383 CTLTYPE_INT, "verbose", 384 SYSCTL_DESCR("Enable verbose output"), 385 NULL, 0, &module_verbose_on, 0, 386 CTL_CREATE, CTL_EOL); 387 } 388 389 /* 390 * module_init_class: 391 * 392 * Initialize all built-in and pre-loaded modules of the 393 * specified class. 394 */ 395 void 396 module_init_class(modclass_t class) 397 { 398 module_t *mod; 399 modinfo_t *mi; 400 401 mutex_enter(&module_lock); 402 /* 403 * Builtins first. These will not depend on pre-loaded modules 404 * (because the kernel would not link). 405 */ 406 do { 407 TAILQ_FOREACH(mod, &module_builtins, mod_chain) { 408 mi = mod->mod_info; 409 if (class != MODULE_CLASS_ANY && class != mi->mi_class) 410 continue; 411 (void)module_do_builtin(mi->mi_name, NULL); 412 break; 413 } 414 } while (mod != NULL); 415 416 /* 417 * Now preloaded modules. These will be pulled off the 418 * list as we call module_do_load(); 419 */ 420 do { 421 TAILQ_FOREACH(mod, &module_bootlist, mod_chain) { 422 mi = mod->mod_info; 423 if (class != MODULE_CLASS_ANY && class != mi->mi_class) 424 continue; 425 module_do_load(mi->mi_name, false, 0, NULL, NULL, 426 class, false); 427 break; 428 } 429 } while (mod != NULL); 430 mutex_exit(&module_lock); 431 } 432 433 /* 434 * module_compatible: 435 * 436 * Return true if the two supplied kernel versions are said to 437 * have the same binary interface for kernel code. The entire 438 * version is signficant for the development tree (-current), 439 * major and minor versions are significant for official 440 * releases of the system. 441 */ 442 bool 443 module_compatible(int v1, int v2) 444 { 445 446 #if __NetBSD_Version__ / 1000000 % 100 == 99 /* -current */ 447 return v1 == v2; 448 #else /* release */ 449 return abs(v1 - v2) < 10000; 450 #endif 451 } 452 453 /* 454 * module_load: 455 * 456 * Load a single module from the file system. 457 */ 458 int 459 module_load(const char *filename, int flags, prop_dictionary_t props, 460 modclass_t class) 461 { 462 int error; 463 464 /* Authorize. */ 465 error = kauth_authorize_system(kauth_cred_get(), KAUTH_SYSTEM_MODULE, 466 0, (void *)(uintptr_t)MODCTL_LOAD, NULL, NULL); 467 if (error != 0) { 468 return error; 469 } 470 471 mutex_enter(&module_lock); 472 error = module_do_load(filename, false, flags, props, NULL, class, 473 false); 474 mutex_exit(&module_lock); 475 476 return error; 477 } 478 479 /* 480 * module_autoload: 481 * 482 * Load a single module from the file system, system initiated. 483 */ 484 int 485 module_autoload(const char *filename, modclass_t class) 486 { 487 int error; 488 489 KASSERT(mutex_owned(&module_lock)); 490 491 /* Nothing if the user has disabled it. */ 492 if (!module_autoload_on) { 493 return EPERM; 494 } 495 496 /* Disallow path separators and magic symlinks. */ 497 if (strchr(filename, '/') != NULL || strchr(filename, '@') != NULL || 498 strchr(filename, '.') != NULL) { 499 return EPERM; 500 } 501 502 /* Authorize. */ 503 error = kauth_authorize_system(kauth_cred_get(), KAUTH_SYSTEM_MODULE, 504 0, (void *)(uintptr_t)MODCTL_LOAD, (void *)(uintptr_t)1, NULL); 505 if (error != 0) { 506 return error; 507 } 508 509 return module_do_load(filename, false, 0, NULL, NULL, class, true); 510 } 511 512 /* 513 * module_unload: 514 * 515 * Find and unload a module by name. 516 */ 517 int 518 module_unload(const char *name) 519 { 520 int error; 521 522 /* Authorize. */ 523 error = kauth_authorize_system(kauth_cred_get(), KAUTH_SYSTEM_MODULE, 524 0, (void *)(uintptr_t)MODCTL_UNLOAD, NULL, NULL); 525 if (error != 0) { 526 return error; 527 } 528 529 mutex_enter(&module_lock); 530 error = module_do_unload(name); 531 mutex_exit(&module_lock); 532 533 return error; 534 } 535 536 /* 537 * module_lookup: 538 * 539 * Look up a module by name. 540 */ 541 module_t * 542 module_lookup(const char *name) 543 { 544 module_t *mod; 545 546 KASSERT(mutex_owned(&module_lock)); 547 548 TAILQ_FOREACH(mod, &module_list, mod_chain) { 549 if (strcmp(mod->mod_info->mi_name, name) == 0) { 550 break; 551 } 552 } 553 554 return mod; 555 } 556 557 /* 558 * module_hold: 559 * 560 * Add a single reference to a module. It's the caller's 561 * responsibility to ensure that the reference is dropped 562 * later. 563 */ 564 int 565 module_hold(const char *name) 566 { 567 module_t *mod; 568 569 mutex_enter(&module_lock); 570 mod = module_lookup(name); 571 if (mod == NULL) { 572 mutex_exit(&module_lock); 573 return ENOENT; 574 } 575 mod->mod_refcnt++; 576 mutex_exit(&module_lock); 577 578 return 0; 579 } 580 581 /* 582 * module_rele: 583 * 584 * Release a reference acquired with module_hold(). 585 */ 586 void 587 module_rele(const char *name) 588 { 589 module_t *mod; 590 591 mutex_enter(&module_lock); 592 mod = module_lookup(name); 593 if (mod == NULL) { 594 mutex_exit(&module_lock); 595 panic("module_rele: gone"); 596 } 597 mod->mod_refcnt--; 598 mutex_exit(&module_lock); 599 } 600 601 /* 602 * module_enqueue: 603 * 604 * Put a module onto the global list and update counters. 605 */ 606 void 607 module_enqueue(module_t *mod) 608 { 609 int i; 610 611 KASSERT(mutex_owned(&module_lock)); 612 613 /* 614 * If there are requisite modules, put at the head of the queue. 615 * This is so that autounload can unload requisite modules with 616 * only one pass through the queue. 617 */ 618 if (mod->mod_nrequired) { 619 TAILQ_INSERT_HEAD(&module_list, mod, mod_chain); 620 621 /* Add references to the requisite modules. */ 622 for (i = 0; i < mod->mod_nrequired; i++) { 623 KASSERT(mod->mod_required[i] != NULL); 624 mod->mod_required[i]->mod_refcnt++; 625 } 626 } else { 627 TAILQ_INSERT_TAIL(&module_list, mod, mod_chain); 628 } 629 module_count++; 630 module_gen++; 631 } 632 633 /* 634 * module_do_builtin: 635 * 636 * Initialize a module from the list of modules that are 637 * already linked into the kernel. 638 */ 639 static int 640 module_do_builtin(const char *name, module_t **modp) 641 { 642 const char *p, *s; 643 char buf[MAXMODNAME]; 644 modinfo_t *mi = NULL; 645 module_t *mod, *mod2, *mod_loaded; 646 size_t len; 647 int error; 648 649 KASSERT(mutex_owned(&module_lock)); 650 651 /* 652 * Search the list to see if we have a module by this name. 653 */ 654 TAILQ_FOREACH(mod, &module_builtins, mod_chain) { 655 if (strcmp(mod->mod_info->mi_name, name) == 0) { 656 mi = mod->mod_info; 657 break; 658 } 659 } 660 661 /* 662 * Check to see if already loaded. This might happen if we 663 * were already loaded as a dependency. 664 */ 665 if ((mod_loaded = module_lookup(name)) != NULL) { 666 KASSERT(mod == NULL); 667 if (modp) 668 *modp = mod_loaded; 669 return 0; 670 } 671 672 /* Note! This is from TAILQ, not immediate above */ 673 if (mi == NULL) 674 panic("can't find `%s'", name); 675 676 /* 677 * Initialize pre-requisites. 678 */ 679 if (mi->mi_required != NULL) { 680 for (s = mi->mi_required; *s != '\0'; s = p) { 681 if (*s == ',') 682 s++; 683 p = s; 684 while (*p != '\0' && *p != ',') 685 p++; 686 len = min(p - s + 1, sizeof(buf)); 687 strlcpy(buf, s, len); 688 if (buf[0] == '\0') 689 break; 690 if (mod->mod_nrequired == MAXMODDEPS - 1) { 691 module_error("too many required modules"); 692 return EINVAL; 693 } 694 error = module_do_builtin(buf, &mod2); 695 if (error != 0) { 696 return error; 697 } 698 mod->mod_required[mod->mod_nrequired++] = mod2; 699 } 700 } 701 702 /* 703 * Try to initialize the module. 704 */ 705 KASSERT(module_active == NULL); 706 module_active = mod; 707 error = (*mi->mi_modcmd)(MODULE_CMD_INIT, NULL); 708 module_active = NULL; 709 if (error != 0) { 710 module_error("builtin module `%s' " 711 "failed to init", mi->mi_name); 712 return error; 713 } 714 715 /* load always succeeds after this point */ 716 717 TAILQ_REMOVE(&module_builtins, mod, mod_chain); 718 module_builtinlist--; 719 if (modp != NULL) { 720 *modp = mod; 721 } 722 if (mi->mi_class == MODULE_CLASS_SECMODEL) 723 secmodel_register(); 724 module_enqueue(mod); 725 return 0; 726 } 727 728 /* 729 * module_do_load: 730 * 731 * Helper routine: load a module from the file system, or one 732 * pushed by the boot loader. 733 */ 734 static int 735 module_do_load(const char *name, bool isdep, int flags, 736 prop_dictionary_t props, module_t **modp, modclass_t class, 737 bool autoload) 738 { 739 static TAILQ_HEAD(,module) pending = TAILQ_HEAD_INITIALIZER(pending); 740 static int depth; 741 const int maxdepth = 6; 742 modinfo_t *mi; 743 module_t *mod, *mod2; 744 prop_dictionary_t filedict; 745 char buf[MAXMODNAME]; 746 const char *s, *p; 747 int error; 748 size_t len; 749 750 KASSERT(mutex_owned(&module_lock)); 751 752 filedict = NULL; 753 error = 0; 754 755 /* 756 * Avoid recursing too far. 757 */ 758 if (++depth > maxdepth) { 759 module_error("too many required modules"); 760 depth--; 761 return EMLINK; 762 } 763 764 /* 765 * Search the list of disabled builtins first. 766 */ 767 TAILQ_FOREACH(mod, &module_builtins, mod_chain) { 768 if (strcmp(mod->mod_info->mi_name, name) == 0) { 769 break; 770 } 771 } 772 if (mod) { 773 if ((flags & MODCTL_LOAD_FORCE) == 0) { 774 module_error("use -f to reinstate " 775 "builtin module \"%s\"", name); 776 depth--; 777 return EPERM; 778 } else { 779 error = module_do_builtin(name, NULL); 780 depth--; 781 return error; 782 } 783 } 784 785 /* 786 * Load the module and link. Before going to the file system, 787 * scan the list of modules loaded by the boot loader. 788 */ 789 TAILQ_FOREACH(mod, &module_bootlist, mod_chain) { 790 if (strcmp(mod->mod_info->mi_name, name) == 0) { 791 TAILQ_REMOVE(&module_bootlist, mod, mod_chain); 792 break; 793 } 794 } 795 if (mod != NULL) { 796 TAILQ_INSERT_TAIL(&pending, mod, mod_chain); 797 } else { 798 /* 799 * If a requisite module, check to see if it is 800 * already present. 801 */ 802 if (isdep) { 803 TAILQ_FOREACH(mod, &module_list, mod_chain) { 804 if (strcmp(mod->mod_info->mi_name, name) == 0) { 805 break; 806 } 807 } 808 if (mod != NULL) { 809 if (modp != NULL) { 810 *modp = mod; 811 } 812 depth--; 813 return 0; 814 } 815 } 816 mod = kmem_zalloc(sizeof(*mod), KM_SLEEP); 817 if (mod == NULL) { 818 module_error("out of memory for `%s'", name); 819 depth--; 820 return ENOMEM; 821 } 822 823 error = module_load_vfs(name, flags, autoload, mod, &filedict); 824 if (error != 0) { 825 kmem_free(mod, sizeof(*mod)); 826 depth--; 827 return error; 828 } 829 mod->mod_source = MODULE_SOURCE_FILESYS; 830 TAILQ_INSERT_TAIL(&pending, mod, mod_chain); 831 832 error = module_fetch_info(mod); 833 if (error != 0) { 834 module_error("cannot fetch module info for `%s'", 835 name); 836 goto fail; 837 } 838 } 839 840 /* 841 * Check compatibility. 842 */ 843 mi = mod->mod_info; 844 if (strlen(mi->mi_name) >= MAXMODNAME) { 845 error = EINVAL; 846 module_error("module name `%s' too long", mi->mi_name); 847 goto fail; 848 } 849 if (!module_compatible(mi->mi_version, __NetBSD_Version__)) { 850 module_error("module built for `%d', system `%d'", 851 mi->mi_version, __NetBSD_Version__); 852 if ((flags & MODCTL_LOAD_FORCE) != 0) { 853 module_error("forced load, system may be unstable"); 854 } else { 855 error = EPROGMISMATCH; 856 goto fail; 857 } 858 } 859 860 /* 861 * If a specific kind of module was requested, ensure that we have 862 * a match. 863 */ 864 if (class != MODULE_CLASS_ANY && class != mi->mi_class) { 865 module_print("incompatible module class for `%s' (%d != %d)", 866 name, class, mi->mi_class); 867 error = ENOENT; 868 goto fail; 869 } 870 871 /* 872 * If loading a dependency, `name' is a plain module name. 873 * The name must match. 874 */ 875 if (isdep && strcmp(mi->mi_name, name) != 0) { 876 module_error("dependency name mismatch (`%s' != `%s')", 877 name, mi->mi_name); 878 error = ENOENT; 879 goto fail; 880 } 881 882 /* 883 * Check to see if the module is already loaded. If so, we may 884 * have been recursively called to handle a dependency, so be sure 885 * to set modp. 886 */ 887 if ((mod2 = module_lookup(mi->mi_name)) != NULL) { 888 if (modp != NULL) 889 *modp = mod2; 890 module_print("module `%s' already loaded", mi->mi_name); 891 error = EEXIST; 892 goto fail; 893 } 894 895 /* 896 * Block circular dependencies. 897 */ 898 TAILQ_FOREACH(mod2, &pending, mod_chain) { 899 if (mod == mod2) { 900 continue; 901 } 902 if (strcmp(mod2->mod_info->mi_name, mi->mi_name) == 0) { 903 error = EDEADLK; 904 module_error("circular dependency detected for `%s'", 905 mi->mi_name); 906 goto fail; 907 } 908 } 909 910 /* 911 * Now try to load any requisite modules. 912 */ 913 if (mi->mi_required != NULL) { 914 for (s = mi->mi_required; *s != '\0'; s = p) { 915 if (*s == ',') 916 s++; 917 p = s; 918 while (*p != '\0' && *p != ',') 919 p++; 920 len = p - s + 1; 921 if (len >= MAXMODNAME) { 922 error = EINVAL; 923 module_error("required module name `%s'" 924 " too long", mi->mi_required); 925 goto fail; 926 } 927 strlcpy(buf, s, len); 928 if (buf[0] == '\0') 929 break; 930 if (mod->mod_nrequired == MAXMODDEPS - 1) { 931 error = EINVAL; 932 module_error("too many required modules (%d)", 933 mod->mod_nrequired); 934 goto fail; 935 } 936 if (strcmp(buf, mi->mi_name) == 0) { 937 error = EDEADLK; 938 module_error("self-dependency detected for " 939 "`%s'", mi->mi_name); 940 goto fail; 941 } 942 error = module_do_load(buf, true, flags, NULL, 943 &mod->mod_required[mod->mod_nrequired++], 944 MODULE_CLASS_ANY, true); 945 if (error != 0) 946 goto fail; 947 } 948 } 949 950 /* 951 * We loaded all needed modules successfully: perform global 952 * relocations and initialize. 953 */ 954 error = kobj_affix(mod->mod_kobj, mi->mi_name); 955 if (error != 0) { 956 /* Cannot touch 'mi' as the module is now gone. */ 957 module_error("unable to affix module `%s'", name); 958 goto fail2; 959 } 960 961 if (filedict) { 962 if (!module_merge_dicts(filedict, props)) { 963 module_error("module properties failed"); 964 error = EINVAL; 965 goto fail; 966 } 967 } 968 KASSERT(module_active == NULL); 969 module_active = mod; 970 error = (*mi->mi_modcmd)(MODULE_CMD_INIT, filedict ? filedict : props); 971 module_active = NULL; 972 if (filedict) { 973 prop_object_release(filedict); 974 filedict = NULL; 975 } 976 if (error != 0) { 977 module_error("modcmd function returned error %d for `%s'", 978 error, mi->mi_name); 979 goto fail; 980 } 981 982 if (mi->mi_class == MODULE_CLASS_SECMODEL) 983 secmodel_register(); 984 985 /* 986 * Good, the module loaded successfully. Put it onto the 987 * list and add references to its requisite modules. 988 */ 989 TAILQ_REMOVE(&pending, mod, mod_chain); 990 module_enqueue(mod); 991 if (modp != NULL) { 992 *modp = mod; 993 } 994 if (autoload) { 995 /* 996 * Arrange to try unloading the module after 997 * a short delay. 998 */ 999 mod->mod_autotime = time_second + module_autotime; 1000 module_thread_kick(); 1001 } 1002 depth--; 1003 return 0; 1004 1005 fail: 1006 kobj_unload(mod->mod_kobj); 1007 fail2: 1008 if (filedict != NULL) { 1009 prop_object_release(filedict); 1010 filedict = NULL; 1011 } 1012 TAILQ_REMOVE(&pending, mod, mod_chain); 1013 kmem_free(mod, sizeof(*mod)); 1014 depth--; 1015 return error; 1016 } 1017 1018 /* 1019 * module_do_unload: 1020 * 1021 * Helper routine: do the dirty work of unloading a module. 1022 */ 1023 static int 1024 module_do_unload(const char *name) 1025 { 1026 module_t *mod; 1027 int error; 1028 u_int i; 1029 1030 KASSERT(mutex_owned(&module_lock)); 1031 1032 mod = module_lookup(name); 1033 if (mod == NULL) { 1034 module_error("module `%s' not found", name); 1035 return ENOENT; 1036 } 1037 if (mod->mod_refcnt != 0) { 1038 module_print("module `%s' busy", name); 1039 return EBUSY; 1040 } 1041 KASSERT(module_active == NULL); 1042 module_active = mod; 1043 error = (*mod->mod_info->mi_modcmd)(MODULE_CMD_FINI, NULL); 1044 module_active = NULL; 1045 if (error != 0) { 1046 module_print("cannot unload module `%s' error=%d", name, 1047 error); 1048 return error; 1049 } 1050 if (mod->mod_info->mi_class == MODULE_CLASS_SECMODEL) 1051 secmodel_deregister(); 1052 module_count--; 1053 TAILQ_REMOVE(&module_list, mod, mod_chain); 1054 for (i = 0; i < mod->mod_nrequired; i++) { 1055 mod->mod_required[i]->mod_refcnt--; 1056 } 1057 if (mod->mod_kobj != NULL) { 1058 kobj_unload(mod->mod_kobj); 1059 } 1060 if (mod->mod_source == MODULE_SOURCE_KERNEL) { 1061 mod->mod_nrequired = 0; /* will be re-parsed */ 1062 TAILQ_INSERT_TAIL(&module_builtins, mod, mod_chain); 1063 module_builtinlist++; 1064 } else { 1065 kmem_free(mod, sizeof(*mod)); 1066 } 1067 module_gen++; 1068 1069 return 0; 1070 } 1071 1072 /* 1073 * module_prime: 1074 * 1075 * Push a module loaded by the bootloader onto our internal 1076 * list. 1077 */ 1078 int 1079 module_prime(void *base, size_t size) 1080 { 1081 module_t *mod; 1082 int error; 1083 1084 mod = kmem_zalloc(sizeof(*mod), KM_SLEEP); 1085 if (mod == NULL) { 1086 return ENOMEM; 1087 } 1088 mod->mod_source = MODULE_SOURCE_BOOT; 1089 1090 error = kobj_load_mem(&mod->mod_kobj, base, size); 1091 if (error != 0) { 1092 kmem_free(mod, sizeof(*mod)); 1093 module_error("unable to load object pushed by boot loader"); 1094 return error; 1095 } 1096 error = module_fetch_info(mod); 1097 if (error != 0) { 1098 kobj_unload(mod->mod_kobj); 1099 kmem_free(mod, sizeof(*mod)); 1100 module_error("unable to load object pushed by boot loader"); 1101 return error; 1102 } 1103 1104 TAILQ_INSERT_TAIL(&module_bootlist, mod, mod_chain); 1105 1106 return 0; 1107 } 1108 1109 /* 1110 * module_fetch_into: 1111 * 1112 * Fetch modinfo record from a loaded module. 1113 */ 1114 static int 1115 module_fetch_info(module_t *mod) 1116 { 1117 int error; 1118 void *addr; 1119 size_t size; 1120 1121 /* 1122 * Find module info record and check compatibility. 1123 */ 1124 error = kobj_find_section(mod->mod_kobj, "link_set_modules", 1125 &addr, &size); 1126 if (error != 0) { 1127 module_error("`link_set_modules' section not present"); 1128 return error; 1129 } 1130 if (size != sizeof(modinfo_t **)) { 1131 module_error("`link_set_modules' section wrong size"); 1132 return error; 1133 } 1134 mod->mod_info = *(modinfo_t **)addr; 1135 1136 return 0; 1137 } 1138 1139 /* 1140 * module_find_section: 1141 * 1142 * Allows a module that is being initialized to look up a section 1143 * within its ELF object. 1144 */ 1145 int 1146 module_find_section(const char *name, void **addr, size_t *size) 1147 { 1148 1149 KASSERT(mutex_owned(&module_lock)); 1150 KASSERT(module_active != NULL); 1151 1152 return kobj_find_section(module_active->mod_kobj, name, addr, size); 1153 } 1154 1155 /* 1156 * module_thread: 1157 * 1158 * Automatically unload modules. We try once to unload autoloaded 1159 * modules after module_autotime seconds. If the system is under 1160 * severe memory pressure, we'll try unloading all modules. 1161 */ 1162 static void 1163 module_thread(void *cookie) 1164 { 1165 module_t *mod, *next; 1166 modinfo_t *mi; 1167 int error; 1168 1169 for (;;) { 1170 mutex_enter(&module_lock); 1171 for (mod = TAILQ_FIRST(&module_list); mod != NULL; mod = next) { 1172 next = TAILQ_NEXT(mod, mod_chain); 1173 if (uvmexp.free < uvmexp.freemin) { 1174 module_thread_ticks = hz; 1175 } else if (mod->mod_autotime == 0) { 1176 continue; 1177 } else if (time_second < mod->mod_autotime) { 1178 module_thread_ticks = hz; 1179 continue; 1180 } else { 1181 mod->mod_autotime = 0; 1182 } 1183 /* 1184 * If this module wants to avoid autounload then 1185 * skip it. Some modules can ping-pong in and out 1186 * because their use is transient but often. 1187 * Example: exec_script. 1188 */ 1189 mi = mod->mod_info; 1190 error = (*mi->mi_modcmd)(MODULE_CMD_AUTOUNLOAD, NULL); 1191 if (error == 0 || error == ENOTTY) { 1192 (void)module_do_unload(mi->mi_name); 1193 } 1194 } 1195 mutex_exit(&module_lock); 1196 1197 mutex_enter(&module_thread_lock); 1198 (void)cv_timedwait(&module_thread_cv, &module_thread_lock, 1199 module_thread_ticks); 1200 module_thread_ticks = 0; 1201 mutex_exit(&module_thread_lock); 1202 } 1203 } 1204 1205 /* 1206 * module_thread: 1207 * 1208 * Kick the module thread into action, perhaps because the 1209 * system is low on memory. 1210 */ 1211 void 1212 module_thread_kick(void) 1213 { 1214 1215 mutex_enter(&module_thread_lock); 1216 module_thread_ticks = hz; 1217 cv_broadcast(&module_thread_cv); 1218 mutex_exit(&module_thread_lock); 1219 } 1220 1221 #ifdef DDB 1222 /* 1223 * module_whatis: 1224 * 1225 * Helper routine for DDB. 1226 */ 1227 void 1228 module_whatis(uintptr_t addr, void (*pr)(const char *, ...)) 1229 { 1230 module_t *mod; 1231 size_t msize; 1232 vaddr_t maddr; 1233 1234 TAILQ_FOREACH(mod, &module_list, mod_chain) { 1235 if (mod->mod_kobj == NULL) { 1236 continue; 1237 } 1238 if (kobj_stat(mod->mod_kobj, &maddr, &msize) != 0) 1239 continue; 1240 if (addr < maddr || addr >= maddr + msize) { 1241 continue; 1242 } 1243 (*pr)("%p is %p+%zu, in kernel module `%s'\n", 1244 (void *)addr, (void *)maddr, 1245 (size_t)(addr - maddr), mod->mod_info->mi_name); 1246 } 1247 } 1248 1249 /* 1250 * module_print_list: 1251 * 1252 * Helper routine for DDB. 1253 */ 1254 void 1255 module_print_list(void (*pr)(const char *, ...)) 1256 { 1257 const char *src; 1258 module_t *mod; 1259 size_t msize; 1260 vaddr_t maddr; 1261 1262 (*pr)("%16s %16s %8s %8s\n", "NAME", "TEXT/DATA", "SIZE", "SOURCE"); 1263 1264 TAILQ_FOREACH(mod, &module_list, mod_chain) { 1265 switch (mod->mod_source) { 1266 case MODULE_SOURCE_KERNEL: 1267 src = "builtin"; 1268 break; 1269 case MODULE_SOURCE_FILESYS: 1270 src = "filesys"; 1271 break; 1272 case MODULE_SOURCE_BOOT: 1273 src = "boot"; 1274 break; 1275 default: 1276 src = "unknown"; 1277 break; 1278 } 1279 if (mod->mod_kobj == NULL) { 1280 maddr = 0; 1281 msize = 0; 1282 } else if (kobj_stat(mod->mod_kobj, &maddr, &msize) != 0) 1283 continue; 1284 (*pr)("%16s %16lx %8ld %8s\n", mod->mod_info->mi_name, 1285 (long)maddr, (long)msize, src); 1286 } 1287 } 1288 #endif /* DDB */ 1289 1290 static bool 1291 module_merge_dicts(prop_dictionary_t existing_dict, 1292 const prop_dictionary_t new_dict) 1293 { 1294 prop_dictionary_keysym_t props_keysym; 1295 prop_object_iterator_t props_iter; 1296 prop_object_t props_obj; 1297 const char *props_key; 1298 bool error; 1299 1300 if (new_dict == NULL) { /* nothing to merge */ 1301 return true; 1302 } 1303 1304 error = false; 1305 props_iter = prop_dictionary_iterator(new_dict); 1306 if (props_iter == NULL) { 1307 return false; 1308 } 1309 1310 while ((props_obj = prop_object_iterator_next(props_iter)) != NULL) { 1311 props_keysym = (prop_dictionary_keysym_t)props_obj; 1312 props_key = prop_dictionary_keysym_cstring_nocopy(props_keysym); 1313 props_obj = prop_dictionary_get_keysym(new_dict, props_keysym); 1314 if ((props_obj == NULL) || !prop_dictionary_set(existing_dict, 1315 props_key, props_obj)) { 1316 error = true; 1317 goto out; 1318 } 1319 } 1320 error = false; 1321 1322 out: 1323 prop_object_iterator_release(props_iter); 1324 1325 return !error; 1326 } 1327