1 /* $NetBSD: kern_module.c,v 1.62 2010/03/18 18:25:45 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 1.62 2010/03/18 18:25:45 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 if (!autoload) { 775 module_error("use -f to reinstate " 776 "builtin module \"%s\"", name); 777 } 778 depth--; 779 return EPERM; 780 } else { 781 error = module_do_builtin(name, NULL); 782 depth--; 783 return error; 784 } 785 } 786 787 /* 788 * Load the module and link. Before going to the file system, 789 * scan the list of modules loaded by the boot loader. 790 */ 791 TAILQ_FOREACH(mod, &module_bootlist, mod_chain) { 792 if (strcmp(mod->mod_info->mi_name, name) == 0) { 793 TAILQ_REMOVE(&module_bootlist, mod, mod_chain); 794 break; 795 } 796 } 797 if (mod != NULL) { 798 TAILQ_INSERT_TAIL(&pending, mod, mod_chain); 799 } else { 800 /* 801 * If a requisite module, check to see if it is 802 * already present. 803 */ 804 if (isdep) { 805 TAILQ_FOREACH(mod, &module_list, mod_chain) { 806 if (strcmp(mod->mod_info->mi_name, name) == 0) { 807 break; 808 } 809 } 810 if (mod != NULL) { 811 if (modp != NULL) { 812 *modp = mod; 813 } 814 depth--; 815 return 0; 816 } 817 } 818 mod = kmem_zalloc(sizeof(*mod), KM_SLEEP); 819 if (mod == NULL) { 820 module_error("out of memory for `%s'", name); 821 depth--; 822 return ENOMEM; 823 } 824 825 error = module_load_vfs(name, flags, autoload, mod, &filedict); 826 if (error != 0) { 827 kmem_free(mod, sizeof(*mod)); 828 depth--; 829 return error; 830 } 831 mod->mod_source = MODULE_SOURCE_FILESYS; 832 TAILQ_INSERT_TAIL(&pending, mod, mod_chain); 833 834 error = module_fetch_info(mod); 835 if (error != 0) { 836 module_error("cannot fetch module info for `%s'", 837 name); 838 goto fail; 839 } 840 } 841 842 /* 843 * Check compatibility. 844 */ 845 mi = mod->mod_info; 846 if (strlen(mi->mi_name) >= MAXMODNAME) { 847 error = EINVAL; 848 module_error("module name `%s' too long", mi->mi_name); 849 goto fail; 850 } 851 if (!module_compatible(mi->mi_version, __NetBSD_Version__)) { 852 module_error("module built for `%d', system `%d'", 853 mi->mi_version, __NetBSD_Version__); 854 if ((flags & MODCTL_LOAD_FORCE) != 0) { 855 module_error("forced load, system may be unstable"); 856 } else { 857 error = EPROGMISMATCH; 858 goto fail; 859 } 860 } 861 862 /* 863 * If a specific kind of module was requested, ensure that we have 864 * a match. 865 */ 866 if (class != MODULE_CLASS_ANY && class != mi->mi_class) { 867 module_print("incompatible module class for `%s' (%d != %d)", 868 name, class, mi->mi_class); 869 error = ENOENT; 870 goto fail; 871 } 872 873 /* 874 * If loading a dependency, `name' is a plain module name. 875 * The name must match. 876 */ 877 if (isdep && strcmp(mi->mi_name, name) != 0) { 878 module_error("dependency name mismatch (`%s' != `%s')", 879 name, mi->mi_name); 880 error = ENOENT; 881 goto fail; 882 } 883 884 /* 885 * Check to see if the module is already loaded. If so, we may 886 * have been recursively called to handle a dependency, so be sure 887 * to set modp. 888 */ 889 if ((mod2 = module_lookup(mi->mi_name)) != NULL) { 890 if (modp != NULL) 891 *modp = mod2; 892 module_print("module `%s' already loaded", mi->mi_name); 893 error = EEXIST; 894 goto fail; 895 } 896 897 /* 898 * Block circular dependencies. 899 */ 900 TAILQ_FOREACH(mod2, &pending, mod_chain) { 901 if (mod == mod2) { 902 continue; 903 } 904 if (strcmp(mod2->mod_info->mi_name, mi->mi_name) == 0) { 905 error = EDEADLK; 906 module_error("circular dependency detected for `%s'", 907 mi->mi_name); 908 goto fail; 909 } 910 } 911 912 /* 913 * Now try to load any requisite modules. 914 */ 915 if (mi->mi_required != NULL) { 916 for (s = mi->mi_required; *s != '\0'; s = p) { 917 if (*s == ',') 918 s++; 919 p = s; 920 while (*p != '\0' && *p != ',') 921 p++; 922 len = p - s + 1; 923 if (len >= MAXMODNAME) { 924 error = EINVAL; 925 module_error("required module name `%s'" 926 " too long", mi->mi_required); 927 goto fail; 928 } 929 strlcpy(buf, s, len); 930 if (buf[0] == '\0') 931 break; 932 if (mod->mod_nrequired == MAXMODDEPS - 1) { 933 error = EINVAL; 934 module_error("too many required modules (%d)", 935 mod->mod_nrequired); 936 goto fail; 937 } 938 if (strcmp(buf, mi->mi_name) == 0) { 939 error = EDEADLK; 940 module_error("self-dependency detected for " 941 "`%s'", mi->mi_name); 942 goto fail; 943 } 944 error = module_do_load(buf, true, flags, NULL, 945 &mod->mod_required[mod->mod_nrequired++], 946 MODULE_CLASS_ANY, true); 947 if (error != 0) 948 goto fail; 949 } 950 } 951 952 /* 953 * We loaded all needed modules successfully: perform global 954 * relocations and initialize. 955 */ 956 error = kobj_affix(mod->mod_kobj, mi->mi_name); 957 if (error != 0) { 958 /* Cannot touch 'mi' as the module is now gone. */ 959 module_error("unable to affix module `%s'", name); 960 goto fail2; 961 } 962 963 if (filedict) { 964 if (!module_merge_dicts(filedict, props)) { 965 module_error("module properties failed"); 966 error = EINVAL; 967 goto fail; 968 } 969 } 970 KASSERT(module_active == NULL); 971 module_active = mod; 972 error = (*mi->mi_modcmd)(MODULE_CMD_INIT, filedict ? filedict : props); 973 module_active = NULL; 974 if (filedict) { 975 prop_object_release(filedict); 976 filedict = NULL; 977 } 978 if (error != 0) { 979 module_error("modcmd function returned error %d for `%s'", 980 error, mi->mi_name); 981 goto fail; 982 } 983 984 if (mi->mi_class == MODULE_CLASS_SECMODEL) 985 secmodel_register(); 986 987 /* 988 * Good, the module loaded successfully. Put it onto the 989 * list and add references to its requisite modules. 990 */ 991 TAILQ_REMOVE(&pending, mod, mod_chain); 992 module_enqueue(mod); 993 if (modp != NULL) { 994 *modp = mod; 995 } 996 if (autoload) { 997 /* 998 * Arrange to try unloading the module after 999 * a short delay. 1000 */ 1001 mod->mod_autotime = time_second + module_autotime; 1002 module_thread_kick(); 1003 } 1004 depth--; 1005 return 0; 1006 1007 fail: 1008 kobj_unload(mod->mod_kobj); 1009 fail2: 1010 if (filedict != NULL) { 1011 prop_object_release(filedict); 1012 filedict = NULL; 1013 } 1014 TAILQ_REMOVE(&pending, mod, mod_chain); 1015 kmem_free(mod, sizeof(*mod)); 1016 depth--; 1017 return error; 1018 } 1019 1020 /* 1021 * module_do_unload: 1022 * 1023 * Helper routine: do the dirty work of unloading a module. 1024 */ 1025 static int 1026 module_do_unload(const char *name) 1027 { 1028 module_t *mod; 1029 int error; 1030 u_int i; 1031 1032 KASSERT(mutex_owned(&module_lock)); 1033 1034 mod = module_lookup(name); 1035 if (mod == NULL) { 1036 module_error("module `%s' not found", name); 1037 return ENOENT; 1038 } 1039 if (mod->mod_refcnt != 0) { 1040 module_print("module `%s' busy", name); 1041 return EBUSY; 1042 } 1043 KASSERT(module_active == NULL); 1044 module_active = mod; 1045 error = (*mod->mod_info->mi_modcmd)(MODULE_CMD_FINI, NULL); 1046 module_active = NULL; 1047 if (error != 0) { 1048 module_print("cannot unload module `%s' error=%d", name, 1049 error); 1050 return error; 1051 } 1052 if (mod->mod_info->mi_class == MODULE_CLASS_SECMODEL) 1053 secmodel_deregister(); 1054 module_count--; 1055 TAILQ_REMOVE(&module_list, mod, mod_chain); 1056 for (i = 0; i < mod->mod_nrequired; i++) { 1057 mod->mod_required[i]->mod_refcnt--; 1058 } 1059 if (mod->mod_kobj != NULL) { 1060 kobj_unload(mod->mod_kobj); 1061 } 1062 if (mod->mod_source == MODULE_SOURCE_KERNEL) { 1063 mod->mod_nrequired = 0; /* will be re-parsed */ 1064 TAILQ_INSERT_TAIL(&module_builtins, mod, mod_chain); 1065 module_builtinlist++; 1066 } else { 1067 kmem_free(mod, sizeof(*mod)); 1068 } 1069 module_gen++; 1070 1071 return 0; 1072 } 1073 1074 /* 1075 * module_prime: 1076 * 1077 * Push a module loaded by the bootloader onto our internal 1078 * list. 1079 */ 1080 int 1081 module_prime(void *base, size_t size) 1082 { 1083 module_t *mod; 1084 int error; 1085 1086 mod = kmem_zalloc(sizeof(*mod), KM_SLEEP); 1087 if (mod == NULL) { 1088 return ENOMEM; 1089 } 1090 mod->mod_source = MODULE_SOURCE_BOOT; 1091 1092 error = kobj_load_mem(&mod->mod_kobj, base, size); 1093 if (error != 0) { 1094 kmem_free(mod, sizeof(*mod)); 1095 module_error("unable to load object pushed by boot loader"); 1096 return error; 1097 } 1098 error = module_fetch_info(mod); 1099 if (error != 0) { 1100 kobj_unload(mod->mod_kobj); 1101 kmem_free(mod, sizeof(*mod)); 1102 module_error("unable to load object pushed by boot loader"); 1103 return error; 1104 } 1105 1106 TAILQ_INSERT_TAIL(&module_bootlist, mod, mod_chain); 1107 1108 return 0; 1109 } 1110 1111 /* 1112 * module_fetch_into: 1113 * 1114 * Fetch modinfo record from a loaded module. 1115 */ 1116 static int 1117 module_fetch_info(module_t *mod) 1118 { 1119 int error; 1120 void *addr; 1121 size_t size; 1122 1123 /* 1124 * Find module info record and check compatibility. 1125 */ 1126 error = kobj_find_section(mod->mod_kobj, "link_set_modules", 1127 &addr, &size); 1128 if (error != 0) { 1129 module_error("`link_set_modules' section not present"); 1130 return error; 1131 } 1132 if (size != sizeof(modinfo_t **)) { 1133 module_error("`link_set_modules' section wrong size"); 1134 return error; 1135 } 1136 mod->mod_info = *(modinfo_t **)addr; 1137 1138 return 0; 1139 } 1140 1141 /* 1142 * module_find_section: 1143 * 1144 * Allows a module that is being initialized to look up a section 1145 * within its ELF object. 1146 */ 1147 int 1148 module_find_section(const char *name, void **addr, size_t *size) 1149 { 1150 1151 KASSERT(mutex_owned(&module_lock)); 1152 KASSERT(module_active != NULL); 1153 1154 return kobj_find_section(module_active->mod_kobj, name, addr, size); 1155 } 1156 1157 /* 1158 * module_thread: 1159 * 1160 * Automatically unload modules. We try once to unload autoloaded 1161 * modules after module_autotime seconds. If the system is under 1162 * severe memory pressure, we'll try unloading all modules. 1163 */ 1164 static void 1165 module_thread(void *cookie) 1166 { 1167 module_t *mod, *next; 1168 modinfo_t *mi; 1169 int error; 1170 1171 for (;;) { 1172 mutex_enter(&module_lock); 1173 for (mod = TAILQ_FIRST(&module_list); mod != NULL; mod = next) { 1174 next = TAILQ_NEXT(mod, mod_chain); 1175 if (mod->mod_source == MODULE_SOURCE_KERNEL) 1176 continue; 1177 if (uvmexp.free < uvmexp.freemin) { 1178 module_thread_ticks = hz; 1179 } else if (mod->mod_autotime == 0) { 1180 continue; 1181 } else if (time_second < mod->mod_autotime) { 1182 module_thread_ticks = hz; 1183 continue; 1184 } else { 1185 mod->mod_autotime = 0; 1186 } 1187 /* 1188 * If this module wants to avoid autounload then 1189 * skip it. Some modules can ping-pong in and out 1190 * because their use is transient but often. 1191 * Example: exec_script. 1192 */ 1193 mi = mod->mod_info; 1194 error = (*mi->mi_modcmd)(MODULE_CMD_AUTOUNLOAD, NULL); 1195 if (error == 0 || error == ENOTTY) { 1196 (void)module_do_unload(mi->mi_name); 1197 } 1198 } 1199 mutex_exit(&module_lock); 1200 1201 mutex_enter(&module_thread_lock); 1202 (void)cv_timedwait(&module_thread_cv, &module_thread_lock, 1203 module_thread_ticks); 1204 module_thread_ticks = 0; 1205 mutex_exit(&module_thread_lock); 1206 } 1207 } 1208 1209 /* 1210 * module_thread: 1211 * 1212 * Kick the module thread into action, perhaps because the 1213 * system is low on memory. 1214 */ 1215 void 1216 module_thread_kick(void) 1217 { 1218 1219 mutex_enter(&module_thread_lock); 1220 module_thread_ticks = hz; 1221 cv_broadcast(&module_thread_cv); 1222 mutex_exit(&module_thread_lock); 1223 } 1224 1225 #ifdef DDB 1226 /* 1227 * module_whatis: 1228 * 1229 * Helper routine for DDB. 1230 */ 1231 void 1232 module_whatis(uintptr_t addr, void (*pr)(const char *, ...)) 1233 { 1234 module_t *mod; 1235 size_t msize; 1236 vaddr_t maddr; 1237 1238 TAILQ_FOREACH(mod, &module_list, mod_chain) { 1239 if (mod->mod_kobj == NULL) { 1240 continue; 1241 } 1242 if (kobj_stat(mod->mod_kobj, &maddr, &msize) != 0) 1243 continue; 1244 if (addr < maddr || addr >= maddr + msize) { 1245 continue; 1246 } 1247 (*pr)("%p is %p+%zu, in kernel module `%s'\n", 1248 (void *)addr, (void *)maddr, 1249 (size_t)(addr - maddr), mod->mod_info->mi_name); 1250 } 1251 } 1252 1253 /* 1254 * module_print_list: 1255 * 1256 * Helper routine for DDB. 1257 */ 1258 void 1259 module_print_list(void (*pr)(const char *, ...)) 1260 { 1261 const char *src; 1262 module_t *mod; 1263 size_t msize; 1264 vaddr_t maddr; 1265 1266 (*pr)("%16s %16s %8s %8s\n", "NAME", "TEXT/DATA", "SIZE", "SOURCE"); 1267 1268 TAILQ_FOREACH(mod, &module_list, mod_chain) { 1269 switch (mod->mod_source) { 1270 case MODULE_SOURCE_KERNEL: 1271 src = "builtin"; 1272 break; 1273 case MODULE_SOURCE_FILESYS: 1274 src = "filesys"; 1275 break; 1276 case MODULE_SOURCE_BOOT: 1277 src = "boot"; 1278 break; 1279 default: 1280 src = "unknown"; 1281 break; 1282 } 1283 if (mod->mod_kobj == NULL) { 1284 maddr = 0; 1285 msize = 0; 1286 } else if (kobj_stat(mod->mod_kobj, &maddr, &msize) != 0) 1287 continue; 1288 (*pr)("%16s %16lx %8ld %8s\n", mod->mod_info->mi_name, 1289 (long)maddr, (long)msize, src); 1290 } 1291 } 1292 #endif /* DDB */ 1293 1294 static bool 1295 module_merge_dicts(prop_dictionary_t existing_dict, 1296 const prop_dictionary_t new_dict) 1297 { 1298 prop_dictionary_keysym_t props_keysym; 1299 prop_object_iterator_t props_iter; 1300 prop_object_t props_obj; 1301 const char *props_key; 1302 bool error; 1303 1304 if (new_dict == NULL) { /* nothing to merge */ 1305 return true; 1306 } 1307 1308 error = false; 1309 props_iter = prop_dictionary_iterator(new_dict); 1310 if (props_iter == NULL) { 1311 return false; 1312 } 1313 1314 while ((props_obj = prop_object_iterator_next(props_iter)) != NULL) { 1315 props_keysym = (prop_dictionary_keysym_t)props_obj; 1316 props_key = prop_dictionary_keysym_cstring_nocopy(props_keysym); 1317 props_obj = prop_dictionary_get_keysym(new_dict, props_keysym); 1318 if ((props_obj == NULL) || !prop_dictionary_set(existing_dict, 1319 props_key, props_obj)) { 1320 error = true; 1321 goto out; 1322 } 1323 } 1324 error = false; 1325 1326 out: 1327 prop_object_iterator_release(props_iter); 1328 1329 return !error; 1330 } 1331