1 /* $NetBSD: kern_module.c,v 1.106 2015/06/22 16:35:13 matt 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 1.106 2015/06/22 16:35:13 matt 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 struct vm_map *module_map; 61 const char *module_machine; 62 char module_base[MODULE_BASE_SIZE]; 63 64 struct modlist module_list = TAILQ_HEAD_INITIALIZER(module_list); 65 struct modlist module_builtins = TAILQ_HEAD_INITIALIZER(module_builtins); 66 static struct modlist module_bootlist = TAILQ_HEAD_INITIALIZER(module_bootlist); 67 68 static module_t *module_active; 69 static bool module_verbose_on; 70 #ifdef MODULAR_DEFAULT_AUTOLOAD 71 static bool module_autoload_on = true; 72 #else 73 static bool module_autoload_on = false; 74 #endif 75 u_int module_count; 76 u_int module_builtinlist; 77 u_int module_autotime = 10; 78 u_int module_gen = 1; 79 static kcondvar_t module_thread_cv; 80 static kmutex_t module_thread_lock; 81 static int module_thread_ticks; 82 int (*module_load_vfs_vec)(const char *, int, bool, module_t *, 83 prop_dictionary_t *) = (void *)eopnotsupp; 84 85 static kauth_listener_t module_listener; 86 87 /* Ensure that the kernel's link set isn't empty. */ 88 static modinfo_t module_dummy; 89 __link_set_add_rodata(modules, module_dummy); 90 91 static module_t *module_newmodule(modsrc_t); 92 static void module_require_force(module_t *); 93 static int module_do_load(const char *, bool, int, prop_dictionary_t, 94 module_t **, modclass_t modclass, bool); 95 static int module_do_unload(const char *, bool); 96 static int module_do_builtin(const char *, module_t **, prop_dictionary_t); 97 static int module_fetch_info(module_t *); 98 static void module_thread(void *); 99 100 static module_t *module_lookup(const char *); 101 static void module_enqueue(module_t *); 102 103 static bool module_merge_dicts(prop_dictionary_t, const prop_dictionary_t); 104 105 static void sysctl_module_setup(void); 106 static int sysctl_module_autotime(SYSCTLFN_PROTO); 107 108 #define MODULE_CLASS_MATCH(mi, modclass) \ 109 ((modclass) == MODULE_CLASS_ANY || (modclass) == (mi)->mi_class) 110 111 static void 112 module_incompat(const modinfo_t *mi, int modclass) 113 { 114 module_error("incompatible module class for `%s' (%d != %d)", 115 mi->mi_name, modclass, mi->mi_class); 116 } 117 118 /* 119 * module_error: 120 * 121 * Utility function: log an error. 122 */ 123 void 124 module_error(const char *fmt, ...) 125 { 126 va_list ap; 127 128 va_start(ap, fmt); 129 printf("WARNING: module error: "); 130 vprintf(fmt, ap); 131 printf("\n"); 132 va_end(ap); 133 } 134 135 /* 136 * module_print: 137 * 138 * Utility function: log verbose output. 139 */ 140 void 141 module_print(const char *fmt, ...) 142 { 143 va_list ap; 144 145 if (module_verbose_on) { 146 va_start(ap, fmt); 147 printf("DEBUG: module: "); 148 vprintf(fmt, ap); 149 printf("\n"); 150 va_end(ap); 151 } 152 } 153 154 static int 155 module_listener_cb(kauth_cred_t cred, kauth_action_t action, void *cookie, 156 void *arg0, void *arg1, void *arg2, void *arg3) 157 { 158 int result; 159 160 result = KAUTH_RESULT_DEFER; 161 162 if (action != KAUTH_SYSTEM_MODULE) 163 return result; 164 165 if ((uintptr_t)arg2 != 0) /* autoload */ 166 result = KAUTH_RESULT_ALLOW; 167 168 return result; 169 } 170 171 /* 172 * Allocate a new module_t 173 */ 174 static module_t * 175 module_newmodule(modsrc_t source) 176 { 177 module_t *mod; 178 179 mod = kmem_zalloc(sizeof(*mod), KM_SLEEP); 180 if (mod != NULL) { 181 mod->mod_source = source; 182 mod->mod_info = NULL; 183 mod->mod_flags = 0; 184 } 185 return mod; 186 } 187 188 /* 189 * Require the -f (force) flag to load a module 190 */ 191 static void 192 module_require_force(struct module *mod) 193 { 194 mod->mod_flags |= MODFLG_MUST_FORCE; 195 } 196 197 /* 198 * Add modules to the builtin list. This can done at boottime or 199 * at runtime if the module is linked into the kernel with an 200 * external linker. All or none of the input will be handled. 201 * Optionally, the modules can be initialized. If they are not 202 * initialized, module_init_class() or module_load() can be used 203 * later, but these are not guaranteed to give atomic results. 204 */ 205 int 206 module_builtin_add(modinfo_t *const *mip, size_t nmodinfo, bool init) 207 { 208 struct module **modp = NULL, *mod_iter; 209 int rv = 0, i, mipskip; 210 211 if (init) { 212 rv = kauth_authorize_system(kauth_cred_get(), 213 KAUTH_SYSTEM_MODULE, 0, (void *)(uintptr_t)MODCTL_LOAD, 214 (void *)(uintptr_t)1, NULL); 215 if (rv) { 216 return rv; 217 } 218 } 219 220 for (i = 0, mipskip = 0; i < nmodinfo; i++) { 221 if (mip[i] == &module_dummy) { 222 KASSERT(nmodinfo > 0); 223 nmodinfo--; 224 } 225 } 226 if (nmodinfo == 0) 227 return 0; 228 229 modp = kmem_zalloc(sizeof(*modp) * nmodinfo, KM_SLEEP); 230 for (i = 0, mipskip = 0; i < nmodinfo; i++) { 231 if (mip[i+mipskip] == &module_dummy) { 232 mipskip++; 233 continue; 234 } 235 modp[i] = module_newmodule(MODULE_SOURCE_KERNEL); 236 modp[i]->mod_info = mip[i+mipskip]; 237 } 238 kernconfig_lock(); 239 240 /* do this in three stages for error recovery and atomicity */ 241 242 /* first check for presence */ 243 for (i = 0; i < nmodinfo; i++) { 244 TAILQ_FOREACH(mod_iter, &module_builtins, mod_chain) { 245 if (strcmp(mod_iter->mod_info->mi_name, 246 modp[i]->mod_info->mi_name) == 0) 247 break; 248 } 249 if (mod_iter) { 250 rv = EEXIST; 251 goto out; 252 } 253 254 if (module_lookup(modp[i]->mod_info->mi_name) != NULL) { 255 rv = EEXIST; 256 goto out; 257 } 258 } 259 260 /* then add to list */ 261 for (i = 0; i < nmodinfo; i++) { 262 TAILQ_INSERT_TAIL(&module_builtins, modp[i], mod_chain); 263 module_builtinlist++; 264 } 265 266 /* finally, init (if required) */ 267 if (init) { 268 for (i = 0; i < nmodinfo; i++) { 269 rv = module_do_builtin(modp[i]->mod_info->mi_name, 270 NULL, NULL); 271 /* throw in the towel, recovery hard & not worth it */ 272 if (rv) 273 panic("builtin module \"%s\" init failed: %d", 274 modp[i]->mod_info->mi_name, rv); 275 } 276 } 277 278 out: 279 kernconfig_unlock(); 280 if (rv != 0) { 281 for (i = 0; i < nmodinfo; i++) { 282 if (modp[i]) 283 kmem_free(modp[i], sizeof(*modp[i])); 284 } 285 } 286 kmem_free(modp, sizeof(*modp) * nmodinfo); 287 return rv; 288 } 289 290 /* 291 * Optionally fini and remove builtin module from the kernel. 292 * Note: the module will now be unreachable except via mi && builtin_add. 293 */ 294 int 295 module_builtin_remove(modinfo_t *mi, bool fini) 296 { 297 struct module *mod; 298 int rv = 0; 299 300 if (fini) { 301 rv = kauth_authorize_system(kauth_cred_get(), 302 KAUTH_SYSTEM_MODULE, 0, (void *)(uintptr_t)MODCTL_UNLOAD, 303 NULL, NULL); 304 if (rv) 305 return rv; 306 307 kernconfig_lock(); 308 rv = module_do_unload(mi->mi_name, true); 309 if (rv) { 310 goto out; 311 } 312 } else { 313 kernconfig_lock(); 314 } 315 TAILQ_FOREACH(mod, &module_builtins, mod_chain) { 316 if (strcmp(mod->mod_info->mi_name, mi->mi_name) == 0) 317 break; 318 } 319 if (mod) { 320 TAILQ_REMOVE(&module_builtins, mod, mod_chain); 321 module_builtinlist--; 322 } else { 323 KASSERT(fini == false); 324 rv = ENOENT; 325 } 326 327 out: 328 kernconfig_unlock(); 329 return rv; 330 } 331 332 /* 333 * module_init: 334 * 335 * Initialize the module subsystem. 336 */ 337 void 338 module_init(void) 339 { 340 __link_set_decl(modules, modinfo_t); 341 extern struct vm_map *module_map; 342 modinfo_t *const *mip; 343 int rv; 344 345 if (module_map == NULL) { 346 module_map = kernel_map; 347 } 348 cv_init(&module_thread_cv, "mod_unld"); 349 mutex_init(&module_thread_lock, MUTEX_DEFAULT, IPL_NONE); 350 351 #ifdef MODULAR /* XXX */ 352 module_init_md(); 353 #endif 354 355 if (!module_machine) 356 module_machine = machine; 357 #if __NetBSD_Version__ / 1000000 % 100 == 99 /* -current */ 358 snprintf(module_base, sizeof(module_base), "/stand/%s/%s/modules", 359 module_machine, osrelease); 360 #else /* release */ 361 snprintf(module_base, sizeof(module_base), "/stand/%s/%d.%d/modules", 362 module_machine, __NetBSD_Version__ / 100000000, 363 __NetBSD_Version__ / 1000000 % 100); 364 #endif 365 366 module_listener = kauth_listen_scope(KAUTH_SCOPE_SYSTEM, 367 module_listener_cb, NULL); 368 369 __link_set_foreach(mip, modules) { 370 if ((rv = module_builtin_add(mip, 1, false)) != 0) 371 module_error("builtin %s failed: %d\n", 372 (*mip)->mi_name, rv); 373 } 374 375 sysctl_module_setup(); 376 } 377 378 /* 379 * module_start_unload_thread: 380 * 381 * Start the auto unload kthread. 382 */ 383 void 384 module_start_unload_thread(void) 385 { 386 int error; 387 388 error = kthread_create(PRI_VM, KTHREAD_MPSAFE, NULL, module_thread, 389 NULL, NULL, "modunload"); 390 if (error != 0) 391 panic("module_init: %d", error); 392 } 393 394 /* 395 * module_builtin_require_force 396 * 397 * Require MODCTL_MUST_FORCE to load any built-in modules that have 398 * not yet been initialized 399 */ 400 void 401 module_builtin_require_force(void) 402 { 403 module_t *mod; 404 405 kernconfig_lock(); 406 TAILQ_FOREACH(mod, &module_builtins, mod_chain) { 407 module_require_force(mod); 408 } 409 kernconfig_unlock(); 410 } 411 412 static struct sysctllog *module_sysctllog; 413 414 static int 415 sysctl_module_autotime(SYSCTLFN_ARGS) 416 { 417 struct sysctlnode node; 418 int t, error; 419 420 t = *(int *)rnode->sysctl_data; 421 422 node = *rnode; 423 node.sysctl_data = &t; 424 error = sysctl_lookup(SYSCTLFN_CALL(&node)); 425 if (error || newp == NULL) 426 return (error); 427 428 if (t < 0) 429 return (EINVAL); 430 431 *(int *)rnode->sysctl_data = t; 432 return (0); 433 } 434 435 static void 436 sysctl_module_setup(void) 437 { 438 const struct sysctlnode *node = NULL; 439 440 sysctl_createv(&module_sysctllog, 0, NULL, &node, 441 CTLFLAG_PERMANENT, 442 CTLTYPE_NODE, "module", 443 SYSCTL_DESCR("Module options"), 444 NULL, 0, NULL, 0, 445 CTL_KERN, CTL_CREATE, CTL_EOL); 446 447 if (node == NULL) 448 return; 449 450 sysctl_createv(&module_sysctllog, 0, &node, NULL, 451 CTLFLAG_PERMANENT | CTLFLAG_READWRITE, 452 CTLTYPE_BOOL, "autoload", 453 SYSCTL_DESCR("Enable automatic load of modules"), 454 NULL, 0, &module_autoload_on, 0, 455 CTL_CREATE, CTL_EOL); 456 sysctl_createv(&module_sysctllog, 0, &node, NULL, 457 CTLFLAG_PERMANENT | CTLFLAG_READWRITE, 458 CTLTYPE_BOOL, "verbose", 459 SYSCTL_DESCR("Enable verbose output"), 460 NULL, 0, &module_verbose_on, 0, 461 CTL_CREATE, CTL_EOL); 462 sysctl_createv(&module_sysctllog, 0, &node, NULL, 463 CTLFLAG_PERMANENT | CTLFLAG_READONLY, 464 CTLTYPE_STRING, "path", 465 SYSCTL_DESCR("Default module load path"), 466 NULL, 0, module_base, 0, 467 CTL_CREATE, CTL_EOL); 468 sysctl_createv(&module_sysctllog, 0, &node, NULL, 469 CTLFLAG_PERMANENT | CTLFLAG_READWRITE, 470 CTLTYPE_INT, "autotime", 471 SYSCTL_DESCR("Auto-unload delay"), 472 sysctl_module_autotime, 0, &module_autotime, 0, 473 CTL_CREATE, CTL_EOL); 474 } 475 476 /* 477 * module_init_class: 478 * 479 * Initialize all built-in and pre-loaded modules of the 480 * specified class. 481 */ 482 void 483 module_init_class(modclass_t modclass) 484 { 485 TAILQ_HEAD(, module) bi_fail = TAILQ_HEAD_INITIALIZER(bi_fail); 486 module_t *mod; 487 modinfo_t *mi; 488 489 kernconfig_lock(); 490 /* 491 * Builtins first. These will not depend on pre-loaded modules 492 * (because the kernel would not link). 493 */ 494 do { 495 TAILQ_FOREACH(mod, &module_builtins, mod_chain) { 496 mi = mod->mod_info; 497 if (!MODULE_CLASS_MATCH(mi, modclass)) 498 continue; 499 /* 500 * If initializing a builtin module fails, don't try 501 * to load it again. But keep it around and queue it 502 * on the builtins list after we're done with module 503 * init. Don't set it to MODFLG_MUST_FORCE in case a 504 * future attempt to initialize can be successful. 505 * (If the module has previously been set to 506 * MODFLG_MUST_FORCE, don't try to override that!) 507 */ 508 if ((mod->mod_flags & MODFLG_MUST_FORCE) || 509 module_do_builtin(mi->mi_name, NULL, NULL) != 0) { 510 TAILQ_REMOVE(&module_builtins, mod, mod_chain); 511 TAILQ_INSERT_TAIL(&bi_fail, mod, mod_chain); 512 } 513 break; 514 } 515 } while (mod != NULL); 516 517 /* 518 * Now preloaded modules. These will be pulled off the 519 * list as we call module_do_load(); 520 */ 521 do { 522 TAILQ_FOREACH(mod, &module_bootlist, mod_chain) { 523 mi = mod->mod_info; 524 if (!MODULE_CLASS_MATCH(mi, modclass)) 525 continue; 526 module_do_load(mi->mi_name, false, 0, NULL, NULL, 527 modclass, false); 528 break; 529 } 530 } while (mod != NULL); 531 532 /* return failed builtin modules to builtin list */ 533 while ((mod = TAILQ_FIRST(&bi_fail)) != NULL) { 534 TAILQ_REMOVE(&bi_fail, mod, mod_chain); 535 TAILQ_INSERT_TAIL(&module_builtins, mod, mod_chain); 536 } 537 538 kernconfig_unlock(); 539 } 540 541 /* 542 * module_compatible: 543 * 544 * Return true if the two supplied kernel versions are said to 545 * have the same binary interface for kernel code. The entire 546 * version is signficant for the development tree (-current), 547 * major and minor versions are significant for official 548 * releases of the system. 549 */ 550 bool 551 module_compatible(int v1, int v2) 552 { 553 554 #if __NetBSD_Version__ / 1000000 % 100 == 99 /* -current */ 555 return v1 == v2; 556 #else /* release */ 557 return abs(v1 - v2) < 10000; 558 #endif 559 } 560 561 /* 562 * module_load: 563 * 564 * Load a single module from the file system. 565 */ 566 int 567 module_load(const char *filename, int flags, prop_dictionary_t props, 568 modclass_t modclass) 569 { 570 int error; 571 572 /* Authorize. */ 573 error = kauth_authorize_system(kauth_cred_get(), KAUTH_SYSTEM_MODULE, 574 0, (void *)(uintptr_t)MODCTL_LOAD, NULL, NULL); 575 if (error != 0) { 576 return error; 577 } 578 579 kernconfig_lock(); 580 error = module_do_load(filename, false, flags, props, NULL, modclass, 581 false); 582 kernconfig_unlock(); 583 584 return error; 585 } 586 587 /* 588 * module_autoload: 589 * 590 * Load a single module from the file system, system initiated. 591 */ 592 int 593 module_autoload(const char *filename, modclass_t modclass) 594 { 595 int error; 596 597 kernconfig_lock(); 598 599 /* Nothing if the user has disabled it. */ 600 if (!module_autoload_on) { 601 kernconfig_unlock(); 602 return EPERM; 603 } 604 605 /* Disallow path separators and magic symlinks. */ 606 if (strchr(filename, '/') != NULL || strchr(filename, '@') != NULL || 607 strchr(filename, '.') != NULL) { 608 kernconfig_unlock(); 609 return EPERM; 610 } 611 612 /* Authorize. */ 613 error = kauth_authorize_system(kauth_cred_get(), KAUTH_SYSTEM_MODULE, 614 0, (void *)(uintptr_t)MODCTL_LOAD, (void *)(uintptr_t)1, NULL); 615 616 if (error == 0) 617 error = module_do_load(filename, false, 0, NULL, NULL, modclass, 618 true); 619 620 kernconfig_unlock(); 621 return error; 622 } 623 624 /* 625 * module_unload: 626 * 627 * Find and unload a module by name. 628 */ 629 int 630 module_unload(const char *name) 631 { 632 int error; 633 634 /* Authorize. */ 635 error = kauth_authorize_system(kauth_cred_get(), KAUTH_SYSTEM_MODULE, 636 0, (void *)(uintptr_t)MODCTL_UNLOAD, NULL, NULL); 637 if (error != 0) { 638 return error; 639 } 640 641 kernconfig_lock(); 642 error = module_do_unload(name, true); 643 kernconfig_unlock(); 644 645 return error; 646 } 647 648 /* 649 * module_lookup: 650 * 651 * Look up a module by name. 652 */ 653 module_t * 654 module_lookup(const char *name) 655 { 656 module_t *mod; 657 658 KASSERT(kernconfig_is_held()); 659 660 TAILQ_FOREACH(mod, &module_list, mod_chain) { 661 if (strcmp(mod->mod_info->mi_name, name) == 0) { 662 break; 663 } 664 } 665 666 return mod; 667 } 668 669 /* 670 * module_hold: 671 * 672 * Add a single reference to a module. It's the caller's 673 * responsibility to ensure that the reference is dropped 674 * later. 675 */ 676 int 677 module_hold(const char *name) 678 { 679 module_t *mod; 680 681 kernconfig_lock(); 682 mod = module_lookup(name); 683 if (mod == NULL) { 684 kernconfig_unlock(); 685 return ENOENT; 686 } 687 mod->mod_refcnt++; 688 kernconfig_unlock(); 689 690 return 0; 691 } 692 693 /* 694 * module_rele: 695 * 696 * Release a reference acquired with module_hold(). 697 */ 698 void 699 module_rele(const char *name) 700 { 701 module_t *mod; 702 703 kernconfig_lock(); 704 mod = module_lookup(name); 705 if (mod == NULL) { 706 kernconfig_unlock(); 707 panic("module_rele: gone"); 708 } 709 mod->mod_refcnt--; 710 kernconfig_unlock(); 711 } 712 713 /* 714 * module_enqueue: 715 * 716 * Put a module onto the global list and update counters. 717 */ 718 void 719 module_enqueue(module_t *mod) 720 { 721 int i; 722 723 KASSERT(kernconfig_is_held()); 724 725 /* 726 * If there are requisite modules, put at the head of the queue. 727 * This is so that autounload can unload requisite modules with 728 * only one pass through the queue. 729 */ 730 if (mod->mod_nrequired) { 731 TAILQ_INSERT_HEAD(&module_list, mod, mod_chain); 732 733 /* Add references to the requisite modules. */ 734 for (i = 0; i < mod->mod_nrequired; i++) { 735 KASSERT(mod->mod_required[i] != NULL); 736 mod->mod_required[i]->mod_refcnt++; 737 } 738 } else { 739 TAILQ_INSERT_TAIL(&module_list, mod, mod_chain); 740 } 741 module_count++; 742 module_gen++; 743 } 744 745 /* 746 * module_do_builtin: 747 * 748 * Initialize a module from the list of modules that are 749 * already linked into the kernel. 750 */ 751 static int 752 module_do_builtin(const char *name, module_t **modp, prop_dictionary_t props) 753 { 754 const char *p, *s; 755 char buf[MAXMODNAME]; 756 modinfo_t *mi = NULL; 757 module_t *mod, *mod2, *mod_loaded, *prev_active; 758 size_t len; 759 int error; 760 761 KASSERT(kernconfig_is_held()); 762 763 /* 764 * Search the list to see if we have a module by this name. 765 */ 766 TAILQ_FOREACH(mod, &module_builtins, mod_chain) { 767 if (strcmp(mod->mod_info->mi_name, name) == 0) { 768 mi = mod->mod_info; 769 break; 770 } 771 } 772 773 /* 774 * Check to see if already loaded. This might happen if we 775 * were already loaded as a dependency. 776 */ 777 if ((mod_loaded = module_lookup(name)) != NULL) { 778 KASSERT(mod == NULL); 779 if (modp) 780 *modp = mod_loaded; 781 return 0; 782 } 783 784 /* Note! This is from TAILQ, not immediate above */ 785 if (mi == NULL) { 786 /* 787 * XXX: We'd like to panic here, but currently in some 788 * cases (such as nfsserver + nfs), the dependee can be 789 * succesfully linked without the dependencies. 790 */ 791 module_error("can't find builtin dependency `%s'", name); 792 return ENOENT; 793 } 794 795 /* 796 * Initialize pre-requisites. 797 */ 798 if (mi->mi_required != NULL) { 799 for (s = mi->mi_required; *s != '\0'; s = p) { 800 if (*s == ',') 801 s++; 802 p = s; 803 while (*p != '\0' && *p != ',') 804 p++; 805 len = min(p - s + 1, sizeof(buf)); 806 strlcpy(buf, s, len); 807 if (buf[0] == '\0') 808 break; 809 if (mod->mod_nrequired == MAXMODDEPS - 1) { 810 module_error("too many required modules " 811 "%d >= %d", mod->mod_nrequired, 812 MAXMODDEPS - 1); 813 return EINVAL; 814 } 815 error = module_do_builtin(buf, &mod2, NULL); 816 if (error != 0) { 817 return error; 818 } 819 mod->mod_required[mod->mod_nrequired++] = mod2; 820 } 821 } 822 823 /* 824 * Try to initialize the module. 825 */ 826 prev_active = module_active; 827 module_active = mod; 828 error = (*mi->mi_modcmd)(MODULE_CMD_INIT, props); 829 module_active = prev_active; 830 if (error != 0) { 831 module_error("builtin module `%s' " 832 "failed to init, error %d", mi->mi_name, error); 833 return error; 834 } 835 836 /* load always succeeds after this point */ 837 838 TAILQ_REMOVE(&module_builtins, mod, mod_chain); 839 module_builtinlist--; 840 if (modp != NULL) { 841 *modp = mod; 842 } 843 module_enqueue(mod); 844 return 0; 845 } 846 847 /* 848 * module_do_load: 849 * 850 * Helper routine: load a module from the file system, or one 851 * pushed by the boot loader. 852 */ 853 static int 854 module_do_load(const char *name, bool isdep, int flags, 855 prop_dictionary_t props, module_t **modp, modclass_t modclass, 856 bool autoload) 857 { 858 #define MODULE_MAX_DEPTH 6 859 860 TAILQ_HEAD(pending_t, module); 861 static int depth = 0; 862 static struct pending_t *pending_lists[MODULE_MAX_DEPTH]; 863 struct pending_t *pending; 864 struct pending_t new_pending = TAILQ_HEAD_INITIALIZER(new_pending); 865 modinfo_t *mi; 866 module_t *mod, *mod2, *prev_active; 867 prop_dictionary_t filedict; 868 char buf[MAXMODNAME]; 869 const char *s, *p; 870 int error; 871 size_t len; 872 873 KASSERT(kernconfig_is_held()); 874 875 filedict = NULL; 876 error = 0; 877 878 /* 879 * Avoid recursing too far. 880 */ 881 if (++depth > MODULE_MAX_DEPTH) { 882 module_error("recursion too deep for `%s' %d > %d", name, 883 depth, MODULE_MAX_DEPTH); 884 depth--; 885 return EMLINK; 886 } 887 888 /* 889 * Set up the pending list for this depth. If this is a 890 * recursive entry, then use same list as for outer call, 891 * else use the locally allocated list. In either case, 892 * remember which one we're using. 893 */ 894 if (isdep) { 895 KASSERT(depth > 1); 896 pending = pending_lists[depth - 2]; 897 } else 898 pending = &new_pending; 899 pending_lists[depth - 1] = pending; 900 901 /* 902 * Search the list of disabled builtins first. 903 */ 904 TAILQ_FOREACH(mod, &module_builtins, mod_chain) { 905 if (strcmp(mod->mod_info->mi_name, name) == 0) { 906 break; 907 } 908 } 909 if (mod) { 910 if ((mod->mod_flags & MODFLG_MUST_FORCE) && 911 (flags & MODCTL_LOAD_FORCE) == 0) { 912 if (!autoload) { 913 module_error("use -f to reinstate " 914 "builtin module `%s'", name); 915 } 916 depth--; 917 return EPERM; 918 } else { 919 error = module_do_builtin(name, modp, props); 920 depth--; 921 return error; 922 } 923 } 924 925 /* 926 * Load the module and link. Before going to the file system, 927 * scan the list of modules loaded by the boot loader. 928 */ 929 TAILQ_FOREACH(mod, &module_bootlist, mod_chain) { 930 if (strcmp(mod->mod_info->mi_name, name) == 0) { 931 TAILQ_REMOVE(&module_bootlist, mod, mod_chain); 932 break; 933 } 934 } 935 if (mod != NULL) { 936 TAILQ_INSERT_TAIL(pending, mod, mod_chain); 937 } else { 938 /* 939 * If a requisite module, check to see if it is 940 * already present. 941 */ 942 if (isdep) { 943 mod = module_lookup(name); 944 if (mod != NULL) { 945 if (modp != NULL) { 946 *modp = mod; 947 } 948 depth--; 949 return 0; 950 } 951 } 952 mod = module_newmodule(MODULE_SOURCE_FILESYS); 953 if (mod == NULL) { 954 module_error("out of memory for `%s'", name); 955 depth--; 956 return ENOMEM; 957 } 958 959 error = module_load_vfs_vec(name, flags, autoload, mod, 960 &filedict); 961 if (error != 0) { 962 #ifdef DEBUG 963 /* 964 * The exec class of modules contains a list of 965 * modules that is the union of all the modules 966 * available for each architecture, so we don't 967 * print an error if they are missing. 968 */ 969 if ((modclass != MODULE_CLASS_EXEC || error != ENOENT) 970 && root_device != NULL) 971 module_error("vfs load failed for `%s', " 972 "error %d", name, error); 973 #endif 974 kmem_free(mod, sizeof(*mod)); 975 depth--; 976 return error; 977 } 978 TAILQ_INSERT_TAIL(pending, mod, mod_chain); 979 980 error = module_fetch_info(mod); 981 if (error != 0) { 982 module_error("cannot fetch info for `%s', error %d", 983 name, error); 984 goto fail; 985 } 986 } 987 988 /* 989 * Check compatibility. 990 */ 991 mi = mod->mod_info; 992 if (strlen(mi->mi_name) >= MAXMODNAME) { 993 error = EINVAL; 994 module_error("module name `%s' longer than %d", mi->mi_name, 995 MAXMODNAME); 996 goto fail; 997 } 998 if (!module_compatible(mi->mi_version, __NetBSD_Version__)) { 999 module_error("module `%s' built for `%d', system `%d'", 1000 mi->mi_name, mi->mi_version, __NetBSD_Version__); 1001 if ((flags & MODCTL_LOAD_FORCE) != 0) { 1002 module_error("forced load, system may be unstable"); 1003 } else { 1004 error = EPROGMISMATCH; 1005 goto fail; 1006 } 1007 } 1008 1009 /* 1010 * If a specific kind of module was requested, ensure that we have 1011 * a match. 1012 */ 1013 if (!MODULE_CLASS_MATCH(mi, modclass)) { 1014 module_incompat(mi, modclass); 1015 error = ENOENT; 1016 goto fail; 1017 } 1018 1019 /* 1020 * If loading a dependency, `name' is a plain module name. 1021 * The name must match. 1022 */ 1023 if (isdep && strcmp(mi->mi_name, name) != 0) { 1024 module_error("dependency name mismatch (`%s' != `%s')", 1025 name, mi->mi_name); 1026 error = ENOENT; 1027 goto fail; 1028 } 1029 1030 /* 1031 * Check to see if the module is already loaded. If so, we may 1032 * have been recursively called to handle a dependency, so be sure 1033 * to set modp. 1034 */ 1035 if ((mod2 = module_lookup(mi->mi_name)) != NULL) { 1036 if (modp != NULL) 1037 *modp = mod2; 1038 module_print("module `%s' already loaded", mi->mi_name); 1039 error = EEXIST; 1040 goto fail; 1041 } 1042 1043 /* 1044 * Block circular dependencies. 1045 */ 1046 TAILQ_FOREACH(mod2, pending, mod_chain) { 1047 if (mod == mod2) { 1048 continue; 1049 } 1050 if (strcmp(mod2->mod_info->mi_name, mi->mi_name) == 0) { 1051 error = EDEADLK; 1052 module_error("circular dependency detected for `%s'", 1053 mi->mi_name); 1054 goto fail; 1055 } 1056 } 1057 1058 /* 1059 * Now try to load any requisite modules. 1060 */ 1061 if (mi->mi_required != NULL) { 1062 for (s = mi->mi_required; *s != '\0'; s = p) { 1063 if (*s == ',') 1064 s++; 1065 p = s; 1066 while (*p != '\0' && *p != ',') 1067 p++; 1068 len = p - s + 1; 1069 if (len >= MAXMODNAME) { 1070 error = EINVAL; 1071 module_error("required module name `%s' " 1072 "longer than %d", mi->mi_required, 1073 MAXMODNAME); 1074 goto fail; 1075 } 1076 strlcpy(buf, s, len); 1077 if (buf[0] == '\0') 1078 break; 1079 if (mod->mod_nrequired == MAXMODDEPS - 1) { 1080 error = EINVAL; 1081 module_error("too many required modules " 1082 "%d >= %d", mod->mod_nrequired, 1083 MAXMODDEPS - 1); 1084 goto fail; 1085 } 1086 if (strcmp(buf, mi->mi_name) == 0) { 1087 error = EDEADLK; 1088 module_error("self-dependency detected for " 1089 "`%s'", mi->mi_name); 1090 goto fail; 1091 } 1092 error = module_do_load(buf, true, flags, NULL, 1093 &mod2, MODULE_CLASS_ANY, true); 1094 if (error != 0) { 1095 module_error("recursive load failed for `%s' " 1096 "(`%s' required), error %d", mi->mi_name, 1097 buf, error); 1098 goto fail; 1099 } 1100 mod->mod_required[mod->mod_nrequired++] = mod2; 1101 } 1102 } 1103 1104 /* 1105 * We loaded all needed modules successfully: perform global 1106 * relocations and initialize. 1107 */ 1108 error = kobj_affix(mod->mod_kobj, mi->mi_name); 1109 if (error != 0) { 1110 /* Cannot touch 'mi' as the module is now gone. */ 1111 module_error("unable to affix module `%s', error %d", name, 1112 error); 1113 goto fail2; 1114 } 1115 1116 if (filedict) { 1117 if (!module_merge_dicts(filedict, props)) { 1118 module_error("module properties failed for %s", name); 1119 error = EINVAL; 1120 goto fail; 1121 } 1122 } 1123 prev_active = module_active; 1124 module_active = mod; 1125 error = (*mi->mi_modcmd)(MODULE_CMD_INIT, filedict ? filedict : props); 1126 module_active = prev_active; 1127 if (filedict) { 1128 prop_object_release(filedict); 1129 filedict = NULL; 1130 } 1131 if (error != 0) { 1132 module_error("modcmd function failed for `%s', error %d", 1133 mi->mi_name, error); 1134 goto fail; 1135 } 1136 1137 /* 1138 * Good, the module loaded successfully. Put it onto the 1139 * list and add references to its requisite modules. 1140 */ 1141 TAILQ_REMOVE(pending, mod, mod_chain); 1142 module_enqueue(mod); 1143 if (modp != NULL) { 1144 *modp = mod; 1145 } 1146 if (autoload && module_autotime > 0) { 1147 /* 1148 * Arrange to try unloading the module after 1149 * a short delay unless auto-unload is disabled. 1150 */ 1151 mod->mod_autotime = time_second + module_autotime; 1152 mod->mod_flags |= MODFLG_AUTO_LOADED; 1153 module_thread_kick(); 1154 } 1155 depth--; 1156 return 0; 1157 1158 fail: 1159 kobj_unload(mod->mod_kobj); 1160 fail2: 1161 if (filedict != NULL) { 1162 prop_object_release(filedict); 1163 filedict = NULL; 1164 } 1165 TAILQ_REMOVE(pending, mod, mod_chain); 1166 kmem_free(mod, sizeof(*mod)); 1167 depth--; 1168 return error; 1169 } 1170 1171 /* 1172 * module_do_unload: 1173 * 1174 * Helper routine: do the dirty work of unloading a module. 1175 */ 1176 static int 1177 module_do_unload(const char *name, bool load_requires_force) 1178 { 1179 module_t *mod, *prev_active; 1180 int error; 1181 u_int i; 1182 1183 KASSERT(kernconfig_is_held()); 1184 KASSERT(name != NULL); 1185 1186 mod = module_lookup(name); 1187 if (mod == NULL) { 1188 module_error("module `%s' not found", name); 1189 return ENOENT; 1190 } 1191 if (mod->mod_refcnt != 0) { 1192 module_print("module `%s' busy", name); 1193 return EBUSY; 1194 } 1195 1196 /* 1197 * Builtin secmodels are there to stay. 1198 */ 1199 if (mod->mod_source == MODULE_SOURCE_KERNEL && 1200 mod->mod_info->mi_class == MODULE_CLASS_SECMODEL) { 1201 return EPERM; 1202 } 1203 1204 prev_active = module_active; 1205 module_active = mod; 1206 error = (*mod->mod_info->mi_modcmd)(MODULE_CMD_FINI, NULL); 1207 module_active = prev_active; 1208 if (error != 0) { 1209 module_print("cannot unload module `%s' error=%d", name, 1210 error); 1211 return error; 1212 } 1213 module_count--; 1214 TAILQ_REMOVE(&module_list, mod, mod_chain); 1215 for (i = 0; i < mod->mod_nrequired; i++) { 1216 mod->mod_required[i]->mod_refcnt--; 1217 } 1218 module_print("unloaded module `%s'", name); 1219 if (mod->mod_kobj != NULL) { 1220 kobj_unload(mod->mod_kobj); 1221 } 1222 if (mod->mod_source == MODULE_SOURCE_KERNEL) { 1223 mod->mod_nrequired = 0; /* will be re-parsed */ 1224 if (load_requires_force) 1225 module_require_force(mod); 1226 TAILQ_INSERT_TAIL(&module_builtins, mod, mod_chain); 1227 module_builtinlist++; 1228 } else { 1229 kmem_free(mod, sizeof(*mod)); 1230 } 1231 module_gen++; 1232 1233 return 0; 1234 } 1235 1236 /* 1237 * module_prime: 1238 * 1239 * Push a module loaded by the bootloader onto our internal 1240 * list. 1241 */ 1242 int 1243 module_prime(const char *name, void *base, size_t size) 1244 { 1245 module_t *mod; 1246 int error; 1247 1248 mod = module_newmodule(MODULE_SOURCE_BOOT); 1249 if (mod == NULL) { 1250 return ENOMEM; 1251 } 1252 1253 error = kobj_load_mem(&mod->mod_kobj, name, base, size); 1254 if (error != 0) { 1255 kmem_free(mod, sizeof(*mod)); 1256 module_error("unable to load `%s' pushed by boot loader, " 1257 "error %d", name, error); 1258 return error; 1259 } 1260 error = module_fetch_info(mod); 1261 if (error != 0) { 1262 kobj_unload(mod->mod_kobj); 1263 kmem_free(mod, sizeof(*mod)); 1264 module_error("unable to load `%s' pushed by boot loader, " 1265 "error %d", name, error); 1266 return error; 1267 } 1268 1269 TAILQ_INSERT_TAIL(&module_bootlist, mod, mod_chain); 1270 1271 return 0; 1272 } 1273 1274 /* 1275 * module_fetch_into: 1276 * 1277 * Fetch modinfo record from a loaded module. 1278 */ 1279 static int 1280 module_fetch_info(module_t *mod) 1281 { 1282 int error; 1283 void *addr; 1284 size_t size; 1285 1286 /* 1287 * Find module info record and check compatibility. 1288 */ 1289 error = kobj_find_section(mod->mod_kobj, "link_set_modules", 1290 &addr, &size); 1291 if (error != 0) { 1292 module_error("`link_set_modules' section not present, " 1293 "error %d", error); 1294 return error; 1295 } 1296 if (size != sizeof(modinfo_t **)) { 1297 module_error("`link_set_modules' section wrong size %zu != %zu", 1298 size, sizeof(modinfo_t **)); 1299 return ENOEXEC; 1300 } 1301 mod->mod_info = *(modinfo_t **)addr; 1302 1303 return 0; 1304 } 1305 1306 /* 1307 * module_find_section: 1308 * 1309 * Allows a module that is being initialized to look up a section 1310 * within its ELF object. 1311 */ 1312 int 1313 module_find_section(const char *name, void **addr, size_t *size) 1314 { 1315 1316 KASSERT(kernconfig_is_held()); 1317 KASSERT(module_active != NULL); 1318 1319 return kobj_find_section(module_active->mod_kobj, name, addr, size); 1320 } 1321 1322 /* 1323 * module_thread: 1324 * 1325 * Automatically unload modules. We try once to unload autoloaded 1326 * modules after module_autotime seconds. If the system is under 1327 * severe memory pressure, we'll try unloading all modules, else if 1328 * module_autotime is zero, we don't try to unload, even if the 1329 * module was previously scheduled for unload. 1330 */ 1331 static void 1332 module_thread(void *cookie) 1333 { 1334 module_t *mod, *next; 1335 modinfo_t *mi; 1336 int error; 1337 1338 for (;;) { 1339 kernconfig_lock(); 1340 for (mod = TAILQ_FIRST(&module_list); mod != NULL; mod = next) { 1341 next = TAILQ_NEXT(mod, mod_chain); 1342 1343 /* skip built-in modules */ 1344 if (mod->mod_source == MODULE_SOURCE_KERNEL) 1345 continue; 1346 /* skip modules that weren't auto-loaded */ 1347 if ((mod->mod_flags & MODFLG_AUTO_LOADED) == 0) 1348 continue; 1349 1350 if (uvmexp.free < uvmexp.freemin) { 1351 module_thread_ticks = hz; 1352 } else if (module_autotime == 0 || 1353 mod->mod_autotime == 0) { 1354 continue; 1355 } else if (time_second < mod->mod_autotime) { 1356 module_thread_ticks = hz; 1357 continue; 1358 } else { 1359 mod->mod_autotime = 0; 1360 } 1361 1362 /* 1363 * If this module wants to avoid autounload then 1364 * skip it. Some modules can ping-pong in and out 1365 * because their use is transient but often. 1366 * Example: exec_script. 1367 */ 1368 mi = mod->mod_info; 1369 error = (*mi->mi_modcmd)(MODULE_CMD_AUTOUNLOAD, NULL); 1370 if (error == 0 || error == ENOTTY) { 1371 (void)module_do_unload(mi->mi_name, false); 1372 } 1373 } 1374 kernconfig_unlock(); 1375 1376 mutex_enter(&module_thread_lock); 1377 (void)cv_timedwait(&module_thread_cv, &module_thread_lock, 1378 module_thread_ticks); 1379 module_thread_ticks = 0; 1380 mutex_exit(&module_thread_lock); 1381 } 1382 } 1383 1384 /* 1385 * module_thread: 1386 * 1387 * Kick the module thread into action, perhaps because the 1388 * system is low on memory. 1389 */ 1390 void 1391 module_thread_kick(void) 1392 { 1393 1394 mutex_enter(&module_thread_lock); 1395 module_thread_ticks = hz; 1396 cv_broadcast(&module_thread_cv); 1397 mutex_exit(&module_thread_lock); 1398 } 1399 1400 #ifdef DDB 1401 /* 1402 * module_whatis: 1403 * 1404 * Helper routine for DDB. 1405 */ 1406 void 1407 module_whatis(uintptr_t addr, void (*pr)(const char *, ...)) 1408 { 1409 module_t *mod; 1410 size_t msize; 1411 vaddr_t maddr; 1412 1413 TAILQ_FOREACH(mod, &module_list, mod_chain) { 1414 if (mod->mod_kobj == NULL) { 1415 continue; 1416 } 1417 if (kobj_stat(mod->mod_kobj, &maddr, &msize) != 0) 1418 continue; 1419 if (addr < maddr || addr >= maddr + msize) { 1420 continue; 1421 } 1422 (*pr)("%p is %p+%zu, in kernel module `%s'\n", 1423 (void *)addr, (void *)maddr, 1424 (size_t)(addr - maddr), mod->mod_info->mi_name); 1425 } 1426 } 1427 1428 /* 1429 * module_print_list: 1430 * 1431 * Helper routine for DDB. 1432 */ 1433 void 1434 module_print_list(void (*pr)(const char *, ...)) 1435 { 1436 const char *src; 1437 module_t *mod; 1438 size_t msize; 1439 vaddr_t maddr; 1440 1441 (*pr)("%16s %16s %8s %8s\n", "NAME", "TEXT/DATA", "SIZE", "SOURCE"); 1442 1443 TAILQ_FOREACH(mod, &module_list, mod_chain) { 1444 switch (mod->mod_source) { 1445 case MODULE_SOURCE_KERNEL: 1446 src = "builtin"; 1447 break; 1448 case MODULE_SOURCE_FILESYS: 1449 src = "filesys"; 1450 break; 1451 case MODULE_SOURCE_BOOT: 1452 src = "boot"; 1453 break; 1454 default: 1455 src = "unknown"; 1456 break; 1457 } 1458 if (mod->mod_kobj == NULL) { 1459 maddr = 0; 1460 msize = 0; 1461 } else if (kobj_stat(mod->mod_kobj, &maddr, &msize) != 0) 1462 continue; 1463 (*pr)("%16s %16lx %8ld %8s\n", mod->mod_info->mi_name, 1464 (long)maddr, (long)msize, src); 1465 } 1466 } 1467 #endif /* DDB */ 1468 1469 static bool 1470 module_merge_dicts(prop_dictionary_t existing_dict, 1471 const prop_dictionary_t new_dict) 1472 { 1473 prop_dictionary_keysym_t props_keysym; 1474 prop_object_iterator_t props_iter; 1475 prop_object_t props_obj; 1476 const char *props_key; 1477 bool error; 1478 1479 if (new_dict == NULL) { /* nothing to merge */ 1480 return true; 1481 } 1482 1483 error = false; 1484 props_iter = prop_dictionary_iterator(new_dict); 1485 if (props_iter == NULL) { 1486 return false; 1487 } 1488 1489 while ((props_obj = prop_object_iterator_next(props_iter)) != NULL) { 1490 props_keysym = (prop_dictionary_keysym_t)props_obj; 1491 props_key = prop_dictionary_keysym_cstring_nocopy(props_keysym); 1492 props_obj = prop_dictionary_get_keysym(new_dict, props_keysym); 1493 if ((props_obj == NULL) || !prop_dictionary_set(existing_dict, 1494 props_key, props_obj)) { 1495 error = true; 1496 goto out; 1497 } 1498 } 1499 error = false; 1500 1501 out: 1502 prop_object_iterator_release(props_iter); 1503 1504 return !error; 1505 } 1506