1 /* $NetBSD: kern_module.c,v 1.94 2013/12/15 21:09:50 pgoyette 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 1.94 2013/12/15 21:09:50 pgoyette 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 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 static bool module_autoload_on = true; 71 u_int module_count; 72 u_int module_builtinlist; 73 u_int module_autotime = 10; 74 u_int module_gen = 1; 75 static kcondvar_t module_thread_cv; 76 static kmutex_t module_thread_lock; 77 static int module_thread_ticks; 78 int (*module_load_vfs_vec)(const char *, int, bool, module_t *, 79 prop_dictionary_t *) = (void *)eopnotsupp; 80 81 static kauth_listener_t module_listener; 82 83 /* Ensure that the kernel's link set isn't empty. */ 84 static modinfo_t module_dummy; 85 __link_set_add_rodata(modules, module_dummy); 86 87 static module_t *module_newmodule(modsrc_t); 88 static void module_require_force(module_t *); 89 static int module_do_load(const char *, bool, int, prop_dictionary_t, 90 module_t **, modclass_t class, bool); 91 static int module_do_unload(const char *, bool); 92 static int module_do_builtin(const char *, module_t **, prop_dictionary_t); 93 static int module_fetch_info(module_t *); 94 static void module_thread(void *); 95 96 static module_t *module_lookup(const char *); 97 static void module_enqueue(module_t *); 98 99 static bool module_merge_dicts(prop_dictionary_t, const prop_dictionary_t); 100 101 static void sysctl_module_setup(void); 102 static int sysctl_module_autotime(SYSCTLFN_PROTO); 103 104 #define MODULE_CLASS_MATCH(mi, class) \ 105 ((class) == MODULE_CLASS_ANY || (class) == (mi)->mi_class) 106 107 static void 108 module_incompat(const modinfo_t *mi, int class) 109 { 110 module_error("incompatible module class for `%s' (%d != %d)", 111 mi->mi_name, class, mi->mi_class); 112 } 113 114 /* 115 * module_error: 116 * 117 * Utility function: log an error. 118 */ 119 void 120 module_error(const char *fmt, ...) 121 { 122 va_list ap; 123 124 va_start(ap, fmt); 125 printf("WARNING: module error: "); 126 vprintf(fmt, ap); 127 printf("\n"); 128 va_end(ap); 129 } 130 131 /* 132 * module_print: 133 * 134 * Utility function: log verbose output. 135 */ 136 void 137 module_print(const char *fmt, ...) 138 { 139 va_list ap; 140 141 if (module_verbose_on) { 142 va_start(ap, fmt); 143 printf("DEBUG: module: "); 144 vprintf(fmt, ap); 145 printf("\n"); 146 va_end(ap); 147 } 148 } 149 150 static int 151 module_listener_cb(kauth_cred_t cred, kauth_action_t action, void *cookie, 152 void *arg0, void *arg1, void *arg2, void *arg3) 153 { 154 int result; 155 156 result = KAUTH_RESULT_DEFER; 157 158 if (action != KAUTH_SYSTEM_MODULE) 159 return result; 160 161 if ((uintptr_t)arg2 != 0) /* autoload */ 162 result = KAUTH_RESULT_ALLOW; 163 164 return result; 165 } 166 167 /* 168 * Allocate a new module_t 169 */ 170 static module_t * 171 module_newmodule(modsrc_t source) 172 { 173 module_t *mod; 174 175 mod = kmem_zalloc(sizeof(*mod), KM_SLEEP); 176 if (mod != NULL) { 177 mod->mod_source = source; 178 mod->mod_info = NULL; 179 mod->mod_flags = 0; 180 } 181 return mod; 182 } 183 184 /* 185 * Require the -f (force) flag to load a module 186 */ 187 static void 188 module_require_force(struct module *mod) 189 { 190 mod->mod_flags |= MODFLG_MUST_FORCE; 191 } 192 193 /* 194 * Add modules to the builtin list. This can done at boottime or 195 * at runtime if the module is linked into the kernel with an 196 * external linker. All or none of the input will be handled. 197 * Optionally, the modules can be initialized. If they are not 198 * initialized, module_init_class() or module_load() can be used 199 * later, but these are not guaranteed to give atomic results. 200 */ 201 int 202 module_builtin_add(modinfo_t *const *mip, size_t nmodinfo, bool init) 203 { 204 struct module **modp = NULL, *mod_iter; 205 int rv = 0, i, mipskip; 206 207 if (init) { 208 rv = kauth_authorize_system(kauth_cred_get(), 209 KAUTH_SYSTEM_MODULE, 0, (void *)(uintptr_t)MODCTL_LOAD, 210 (void *)(uintptr_t)1, NULL); 211 if (rv) { 212 return rv; 213 } 214 } 215 216 for (i = 0, mipskip = 0; i < nmodinfo; i++) { 217 if (mip[i] == &module_dummy) { 218 KASSERT(nmodinfo > 0); 219 nmodinfo--; 220 } 221 } 222 if (nmodinfo == 0) 223 return 0; 224 225 modp = kmem_zalloc(sizeof(*modp) * nmodinfo, KM_SLEEP); 226 for (i = 0, mipskip = 0; i < nmodinfo; i++) { 227 if (mip[i+mipskip] == &module_dummy) { 228 mipskip++; 229 continue; 230 } 231 modp[i] = module_newmodule(MODULE_SOURCE_KERNEL); 232 modp[i]->mod_info = mip[i+mipskip]; 233 } 234 kernconfig_lock(); 235 236 /* do this in three stages for error recovery and atomicity */ 237 238 /* first check for presence */ 239 for (i = 0; i < nmodinfo; i++) { 240 TAILQ_FOREACH(mod_iter, &module_builtins, mod_chain) { 241 if (strcmp(mod_iter->mod_info->mi_name, 242 modp[i]->mod_info->mi_name) == 0) 243 break; 244 } 245 if (mod_iter) { 246 rv = EEXIST; 247 goto out; 248 } 249 250 if (module_lookup(modp[i]->mod_info->mi_name) != NULL) { 251 rv = EEXIST; 252 goto out; 253 } 254 } 255 256 /* then add to list */ 257 for (i = 0; i < nmodinfo; i++) { 258 TAILQ_INSERT_TAIL(&module_builtins, modp[i], mod_chain); 259 module_builtinlist++; 260 } 261 262 /* finally, init (if required) */ 263 if (init) { 264 for (i = 0; i < nmodinfo; i++) { 265 rv = module_do_builtin(modp[i]->mod_info->mi_name, 266 NULL, NULL); 267 /* throw in the towel, recovery hard & not worth it */ 268 if (rv) 269 panic("builtin module \"%s\" init failed: %d", 270 modp[i]->mod_info->mi_name, rv); 271 } 272 } 273 274 out: 275 kernconfig_unlock(); 276 if (rv != 0) { 277 for (i = 0; i < nmodinfo; i++) { 278 if (modp[i]) 279 kmem_free(modp[i], sizeof(*modp[i])); 280 } 281 } 282 kmem_free(modp, sizeof(*modp) * nmodinfo); 283 return rv; 284 } 285 286 /* 287 * Optionally fini and remove builtin module from the kernel. 288 * Note: the module will now be unreachable except via mi && builtin_add. 289 */ 290 int 291 module_builtin_remove(modinfo_t *mi, bool fini) 292 { 293 struct module *mod; 294 int rv = 0; 295 296 if (fini) { 297 rv = kauth_authorize_system(kauth_cred_get(), 298 KAUTH_SYSTEM_MODULE, 0, (void *)(uintptr_t)MODCTL_UNLOAD, 299 NULL, NULL); 300 if (rv) 301 return rv; 302 303 kernconfig_lock(); 304 rv = module_do_unload(mi->mi_name, true); 305 if (rv) { 306 goto out; 307 } 308 } else { 309 kernconfig_lock(); 310 } 311 TAILQ_FOREACH(mod, &module_builtins, mod_chain) { 312 if (strcmp(mod->mod_info->mi_name, mi->mi_name) == 0) 313 break; 314 } 315 if (mod) { 316 TAILQ_REMOVE(&module_builtins, mod, mod_chain); 317 module_builtinlist--; 318 } else { 319 KASSERT(fini == false); 320 rv = ENOENT; 321 } 322 323 out: 324 kernconfig_unlock(); 325 return rv; 326 } 327 328 /* 329 * module_init: 330 * 331 * Initialize the module subsystem. 332 */ 333 void 334 module_init(void) 335 { 336 __link_set_decl(modules, modinfo_t); 337 extern struct vm_map *module_map; 338 modinfo_t *const *mip; 339 int rv; 340 341 if (module_map == NULL) { 342 module_map = kernel_map; 343 } 344 cv_init(&module_thread_cv, "mod_unld"); 345 mutex_init(&module_thread_lock, MUTEX_DEFAULT, IPL_NONE); 346 347 #ifdef MODULAR /* XXX */ 348 module_init_md(); 349 #endif 350 351 if (!module_machine) 352 module_machine = machine; 353 #if __NetBSD_Version__ / 1000000 % 100 == 99 /* -current */ 354 snprintf(module_base, sizeof(module_base), "/stand/%s/%s/modules", 355 module_machine, osrelease); 356 #else /* release */ 357 snprintf(module_base, sizeof(module_base), "/stand/%s/%d.%d/modules", 358 module_machine, __NetBSD_Version__ / 100000000, 359 __NetBSD_Version__ / 1000000 % 100); 360 #endif 361 362 module_listener = kauth_listen_scope(KAUTH_SCOPE_SYSTEM, 363 module_listener_cb, NULL); 364 365 __link_set_foreach(mip, modules) { 366 if ((rv = module_builtin_add(mip, 1, false)) != 0) 367 module_error("builtin %s failed: %d\n", 368 (*mip)->mi_name, rv); 369 } 370 371 sysctl_module_setup(); 372 } 373 374 /* 375 * module_start_unload_thread: 376 * 377 * Start the auto unload kthread. 378 */ 379 void 380 module_start_unload_thread(void) 381 { 382 int error; 383 384 error = kthread_create(PRI_VM, KTHREAD_MPSAFE, NULL, module_thread, 385 NULL, NULL, "modunload"); 386 if (error != 0) 387 panic("module_init: %d", error); 388 } 389 390 /* 391 * module_builtin_require_force 392 * 393 * Require MODCTL_MUST_FORCE to load any built-in modules that have 394 * not yet been initialized 395 */ 396 void 397 module_builtin_require_force(void) 398 { 399 module_t *mod; 400 401 kernconfig_lock(); 402 TAILQ_FOREACH(mod, &module_builtins, mod_chain) { 403 module_require_force(mod); 404 } 405 kernconfig_unlock(); 406 } 407 408 static struct sysctllog *module_sysctllog; 409 410 static int 411 sysctl_module_autotime(SYSCTLFN_ARGS) 412 { 413 struct sysctlnode node; 414 int t, error; 415 416 t = *(int *)rnode->sysctl_data; 417 418 node = *rnode; 419 node.sysctl_data = &t; 420 error = sysctl_lookup(SYSCTLFN_CALL(&node)); 421 if (error || newp == NULL) 422 return (error); 423 424 if (t < 0) 425 return (EINVAL); 426 427 *(int *)rnode->sysctl_data = t; 428 return (0); 429 } 430 431 static void 432 sysctl_module_setup(void) 433 { 434 const struct sysctlnode *node = NULL; 435 436 sysctl_createv(&module_sysctllog, 0, NULL, NULL, 437 CTLFLAG_PERMANENT, 438 CTLTYPE_NODE, "kern", NULL, 439 NULL, 0, NULL, 0, 440 CTL_KERN, CTL_EOL); 441 sysctl_createv(&module_sysctllog, 0, NULL, &node, 442 CTLFLAG_PERMANENT, 443 CTLTYPE_NODE, "module", 444 SYSCTL_DESCR("Module options"), 445 NULL, 0, NULL, 0, 446 CTL_KERN, CTL_CREATE, CTL_EOL); 447 448 if (node == NULL) 449 return; 450 451 sysctl_createv(&module_sysctllog, 0, &node, NULL, 452 CTLFLAG_PERMANENT | CTLFLAG_READWRITE, 453 CTLTYPE_BOOL, "autoload", 454 SYSCTL_DESCR("Enable automatic load of modules"), 455 NULL, 0, &module_autoload_on, 0, 456 CTL_CREATE, CTL_EOL); 457 sysctl_createv(&module_sysctllog, 0, &node, NULL, 458 CTLFLAG_PERMANENT | CTLFLAG_READWRITE, 459 CTLTYPE_BOOL, "verbose", 460 SYSCTL_DESCR("Enable verbose output"), 461 NULL, 0, &module_verbose_on, 0, 462 CTL_CREATE, CTL_EOL); 463 sysctl_createv(&module_sysctllog, 0, &node, NULL, 464 CTLFLAG_PERMANENT | CTLFLAG_READWRITE, 465 CTLTYPE_INT, "autotime", 466 SYSCTL_DESCR("Auto-unload delay"), 467 sysctl_module_autotime, 0, &module_autotime, 0, 468 CTL_CREATE, CTL_EOL); 469 } 470 471 /* 472 * module_init_class: 473 * 474 * Initialize all built-in and pre-loaded modules of the 475 * specified class. 476 */ 477 void 478 module_init_class(modclass_t class) 479 { 480 TAILQ_HEAD(, module) bi_fail = TAILQ_HEAD_INITIALIZER(bi_fail); 481 module_t *mod; 482 modinfo_t *mi; 483 484 kernconfig_lock(); 485 /* 486 * Builtins first. These will not depend on pre-loaded modules 487 * (because the kernel would not link). 488 */ 489 do { 490 TAILQ_FOREACH(mod, &module_builtins, mod_chain) { 491 mi = mod->mod_info; 492 if (!MODULE_CLASS_MATCH(mi, class)) 493 continue; 494 /* 495 * If initializing a builtin module fails, don't try 496 * to load it again. But keep it around and queue it 497 * on the builtins list after we're done with module 498 * init. Don't set it to MODFLG_MUST_FORCE in case a 499 * future attempt to initialize can be successful. 500 * (If the module has previously been set to 501 * MODFLG_MUST_FORCE, don't try to override that!) 502 */ 503 if (mod->mod_flags & MODFLG_MUST_FORCE || 504 module_do_builtin(mi->mi_name, NULL, NULL) != 0) { 505 TAILQ_REMOVE(&module_builtins, mod, mod_chain); 506 TAILQ_INSERT_TAIL(&bi_fail, mod, mod_chain); 507 } 508 break; 509 } 510 } while (mod != NULL); 511 512 /* 513 * Now preloaded modules. These will be pulled off the 514 * list as we call module_do_load(); 515 */ 516 do { 517 TAILQ_FOREACH(mod, &module_bootlist, mod_chain) { 518 mi = mod->mod_info; 519 if (!MODULE_CLASS_MATCH(mi, class)) 520 continue; 521 module_do_load(mi->mi_name, false, 0, NULL, NULL, 522 class, false); 523 break; 524 } 525 } while (mod != NULL); 526 527 /* return failed builtin modules to builtin list */ 528 while ((mod = TAILQ_FIRST(&bi_fail)) != NULL) { 529 TAILQ_REMOVE(&bi_fail, mod, mod_chain); 530 TAILQ_INSERT_TAIL(&module_builtins, mod, mod_chain); 531 } 532 533 kernconfig_unlock(); 534 } 535 536 /* 537 * module_compatible: 538 * 539 * Return true if the two supplied kernel versions are said to 540 * have the same binary interface for kernel code. The entire 541 * version is signficant for the development tree (-current), 542 * major and minor versions are significant for official 543 * releases of the system. 544 */ 545 bool 546 module_compatible(int v1, int v2) 547 { 548 549 #if __NetBSD_Version__ / 1000000 % 100 == 99 /* -current */ 550 return v1 == v2; 551 #else /* release */ 552 return abs(v1 - v2) < 10000; 553 #endif 554 } 555 556 /* 557 * module_load: 558 * 559 * Load a single module from the file system. 560 */ 561 int 562 module_load(const char *filename, int flags, prop_dictionary_t props, 563 modclass_t class) 564 { 565 int error; 566 567 /* Authorize. */ 568 error = kauth_authorize_system(kauth_cred_get(), KAUTH_SYSTEM_MODULE, 569 0, (void *)(uintptr_t)MODCTL_LOAD, NULL, NULL); 570 if (error != 0) { 571 return error; 572 } 573 574 kernconfig_lock(); 575 error = module_do_load(filename, false, flags, props, NULL, class, 576 false); 577 kernconfig_unlock(); 578 579 return error; 580 } 581 582 /* 583 * module_autoload: 584 * 585 * Load a single module from the file system, system initiated. 586 */ 587 int 588 module_autoload(const char *filename, modclass_t class) 589 { 590 int error; 591 592 kernconfig_lock(); 593 594 /* Nothing if the user has disabled it. */ 595 if (!module_autoload_on) { 596 kernconfig_unlock(); 597 return EPERM; 598 } 599 600 /* Disallow path separators and magic symlinks. */ 601 if (strchr(filename, '/') != NULL || strchr(filename, '@') != NULL || 602 strchr(filename, '.') != NULL) { 603 kernconfig_unlock(); 604 return EPERM; 605 } 606 607 /* Authorize. */ 608 error = kauth_authorize_system(kauth_cred_get(), KAUTH_SYSTEM_MODULE, 609 0, (void *)(uintptr_t)MODCTL_LOAD, (void *)(uintptr_t)1, NULL); 610 611 if (error == 0) 612 error = module_do_load(filename, false, 0, NULL, NULL, class, 613 true); 614 615 kernconfig_unlock(); 616 return error; 617 } 618 619 /* 620 * module_unload: 621 * 622 * Find and unload a module by name. 623 */ 624 int 625 module_unload(const char *name) 626 { 627 int error; 628 629 /* Authorize. */ 630 error = kauth_authorize_system(kauth_cred_get(), KAUTH_SYSTEM_MODULE, 631 0, (void *)(uintptr_t)MODCTL_UNLOAD, NULL, NULL); 632 if (error != 0) { 633 return error; 634 } 635 636 kernconfig_lock(); 637 error = module_do_unload(name, true); 638 kernconfig_unlock(); 639 640 return error; 641 } 642 643 /* 644 * module_lookup: 645 * 646 * Look up a module by name. 647 */ 648 module_t * 649 module_lookup(const char *name) 650 { 651 module_t *mod; 652 653 KASSERT(kernconfig_is_held()); 654 655 TAILQ_FOREACH(mod, &module_list, mod_chain) { 656 if (strcmp(mod->mod_info->mi_name, name) == 0) { 657 break; 658 } 659 } 660 661 return mod; 662 } 663 664 /* 665 * module_hold: 666 * 667 * Add a single reference to a module. It's the caller's 668 * responsibility to ensure that the reference is dropped 669 * later. 670 */ 671 int 672 module_hold(const char *name) 673 { 674 module_t *mod; 675 676 kernconfig_lock(); 677 mod = module_lookup(name); 678 if (mod == NULL) { 679 kernconfig_unlock(); 680 return ENOENT; 681 } 682 mod->mod_refcnt++; 683 kernconfig_unlock(); 684 685 return 0; 686 } 687 688 /* 689 * module_rele: 690 * 691 * Release a reference acquired with module_hold(). 692 */ 693 void 694 module_rele(const char *name) 695 { 696 module_t *mod; 697 698 kernconfig_lock(); 699 mod = module_lookup(name); 700 if (mod == NULL) { 701 kernconfig_unlock(); 702 panic("module_rele: gone"); 703 } 704 mod->mod_refcnt--; 705 kernconfig_unlock(); 706 } 707 708 /* 709 * module_enqueue: 710 * 711 * Put a module onto the global list and update counters. 712 */ 713 void 714 module_enqueue(module_t *mod) 715 { 716 int i; 717 718 KASSERT(kernconfig_is_held()); 719 720 /* 721 * If there are requisite modules, put at the head of the queue. 722 * This is so that autounload can unload requisite modules with 723 * only one pass through the queue. 724 */ 725 if (mod->mod_nrequired) { 726 TAILQ_INSERT_HEAD(&module_list, mod, mod_chain); 727 728 /* Add references to the requisite modules. */ 729 for (i = 0; i < mod->mod_nrequired; i++) { 730 KASSERT(mod->mod_required[i] != NULL); 731 mod->mod_required[i]->mod_refcnt++; 732 } 733 } else { 734 TAILQ_INSERT_TAIL(&module_list, mod, mod_chain); 735 } 736 module_count++; 737 module_gen++; 738 } 739 740 /* 741 * module_do_builtin: 742 * 743 * Initialize a module from the list of modules that are 744 * already linked into the kernel. 745 */ 746 static int 747 module_do_builtin(const char *name, module_t **modp, prop_dictionary_t props) 748 { 749 const char *p, *s; 750 char buf[MAXMODNAME]; 751 modinfo_t *mi = NULL; 752 module_t *mod, *mod2, *mod_loaded, *prev_active; 753 size_t len; 754 int error; 755 756 KASSERT(kernconfig_is_held()); 757 758 /* 759 * Search the list to see if we have a module by this name. 760 */ 761 TAILQ_FOREACH(mod, &module_builtins, mod_chain) { 762 if (strcmp(mod->mod_info->mi_name, name) == 0) { 763 mi = mod->mod_info; 764 break; 765 } 766 } 767 768 /* 769 * Check to see if already loaded. This might happen if we 770 * were already loaded as a dependency. 771 */ 772 if ((mod_loaded = module_lookup(name)) != NULL) { 773 KASSERT(mod == NULL); 774 if (modp) 775 *modp = mod_loaded; 776 return 0; 777 } 778 779 /* Note! This is from TAILQ, not immediate above */ 780 if (mi == NULL) { 781 /* 782 * XXX: We'd like to panic here, but currently in some 783 * cases (such as nfsserver + nfs), the dependee can be 784 * succesfully linked without the dependencies. 785 */ 786 module_error("can't find builtin dependency `%s'", name); 787 return ENOENT; 788 } 789 790 /* 791 * Initialize pre-requisites. 792 */ 793 if (mi->mi_required != NULL) { 794 for (s = mi->mi_required; *s != '\0'; s = p) { 795 if (*s == ',') 796 s++; 797 p = s; 798 while (*p != '\0' && *p != ',') 799 p++; 800 len = min(p - s + 1, sizeof(buf)); 801 strlcpy(buf, s, len); 802 if (buf[0] == '\0') 803 break; 804 if (mod->mod_nrequired == MAXMODDEPS - 1) { 805 module_error("too many required modules " 806 "%d >= %d", mod->mod_nrequired, 807 MAXMODDEPS - 1); 808 return EINVAL; 809 } 810 error = module_do_builtin(buf, &mod2, NULL); 811 if (error != 0) { 812 return error; 813 } 814 mod->mod_required[mod->mod_nrequired++] = mod2; 815 } 816 } 817 818 /* 819 * Try to initialize the module. 820 */ 821 prev_active = module_active; 822 module_active = mod; 823 error = (*mi->mi_modcmd)(MODULE_CMD_INIT, props); 824 module_active = prev_active; 825 if (error != 0) { 826 module_error("builtin module `%s' " 827 "failed to init, error %d", mi->mi_name, error); 828 return error; 829 } 830 831 /* load always succeeds after this point */ 832 833 TAILQ_REMOVE(&module_builtins, mod, mod_chain); 834 module_builtinlist--; 835 if (modp != NULL) { 836 *modp = mod; 837 } 838 module_enqueue(mod); 839 return 0; 840 } 841 842 /* 843 * module_do_load: 844 * 845 * Helper routine: load a module from the file system, or one 846 * pushed by the boot loader. 847 */ 848 static int 849 module_do_load(const char *name, bool isdep, int flags, 850 prop_dictionary_t props, module_t **modp, modclass_t class, 851 bool autoload) 852 { 853 #define MODULE_MAX_DEPTH 6 854 855 TAILQ_HEAD(pending_t, module); 856 static int depth = 0; 857 static struct pending_t *pending_lists[MODULE_MAX_DEPTH]; 858 struct pending_t *pending; 859 struct pending_t new_pending = TAILQ_HEAD_INITIALIZER(new_pending); 860 modinfo_t *mi; 861 module_t *mod, *mod2, *prev_active; 862 prop_dictionary_t filedict; 863 char buf[MAXMODNAME]; 864 const char *s, *p; 865 int error; 866 size_t len; 867 868 KASSERT(kernconfig_is_held()); 869 870 filedict = NULL; 871 error = 0; 872 873 /* 874 * Avoid recursing too far. 875 */ 876 if (++depth > MODULE_MAX_DEPTH) { 877 module_error("recursion too deep for `%s' %d > %d", name, 878 depth, MODULE_MAX_DEPTH); 879 depth--; 880 return EMLINK; 881 } 882 883 /* 884 * Set up the pending list for this depth. If this is a 885 * recursive entry, then use same list as for outer call, 886 * else use the locally allocated list. In either case, 887 * remember which one we're using. 888 */ 889 if (isdep) { 890 KASSERT(depth > 1); 891 pending = pending_lists[depth - 2]; 892 } else 893 pending = &new_pending; 894 pending_lists[depth - 1] = pending; 895 896 /* 897 * Search the list of disabled builtins first. 898 */ 899 TAILQ_FOREACH(mod, &module_builtins, mod_chain) { 900 if (strcmp(mod->mod_info->mi_name, name) == 0) { 901 break; 902 } 903 } 904 if (mod) { 905 if ((mod->mod_flags & MODFLG_MUST_FORCE) && 906 (flags & MODCTL_LOAD_FORCE) == 0) { 907 if (!autoload) { 908 module_error("use -f to reinstate " 909 "builtin module `%s'", name); 910 } 911 depth--; 912 return EPERM; 913 } else { 914 error = module_do_builtin(name, modp, props); 915 depth--; 916 return error; 917 } 918 } 919 920 /* 921 * Load the module and link. Before going to the file system, 922 * scan the list of modules loaded by the boot loader. 923 */ 924 TAILQ_FOREACH(mod, &module_bootlist, mod_chain) { 925 if (strcmp(mod->mod_info->mi_name, name) == 0) { 926 TAILQ_REMOVE(&module_bootlist, mod, mod_chain); 927 break; 928 } 929 } 930 if (mod != NULL) { 931 TAILQ_INSERT_TAIL(pending, mod, mod_chain); 932 } else { 933 /* 934 * If a requisite module, check to see if it is 935 * already present. 936 */ 937 if (isdep) { 938 mod = module_lookup(name); 939 if (mod != NULL) { 940 if (modp != NULL) { 941 *modp = mod; 942 } 943 depth--; 944 return 0; 945 } 946 } 947 mod = module_newmodule(MODULE_SOURCE_FILESYS); 948 if (mod == NULL) { 949 module_error("out of memory for `%s'", name); 950 depth--; 951 return ENOMEM; 952 } 953 954 error = module_load_vfs_vec(name, flags, autoload, mod, 955 &filedict); 956 if (error != 0) { 957 #ifdef DEBUG 958 /* 959 * The exec class of modules contains a list of 960 * modules that is the union of all the modules 961 * available for each architecture, so we don't 962 * print an error if they are missing. 963 */ 964 if (class != MODULE_CLASS_EXEC || error != ENOENT) 965 module_error("vfs load failed for `%s', " 966 "error %d", name, error); 967 #endif 968 kmem_free(mod, sizeof(*mod)); 969 depth--; 970 return error; 971 } 972 TAILQ_INSERT_TAIL(pending, mod, mod_chain); 973 974 error = module_fetch_info(mod); 975 if (error != 0) { 976 module_error("cannot fetch info for `%s', error %d", 977 name, error); 978 goto fail; 979 } 980 } 981 982 /* 983 * Check compatibility. 984 */ 985 mi = mod->mod_info; 986 if (strlen(mi->mi_name) >= MAXMODNAME) { 987 error = EINVAL; 988 module_error("module name `%s' longer than %d", mi->mi_name, 989 MAXMODNAME); 990 goto fail; 991 } 992 if (!module_compatible(mi->mi_version, __NetBSD_Version__)) { 993 module_error("module `%s' built for `%d', system `%d'", 994 mi->mi_name, mi->mi_version, __NetBSD_Version__); 995 if ((flags & MODCTL_LOAD_FORCE) != 0) { 996 module_error("forced load, system may be unstable"); 997 } else { 998 error = EPROGMISMATCH; 999 goto fail; 1000 } 1001 } 1002 1003 /* 1004 * If a specific kind of module was requested, ensure that we have 1005 * a match. 1006 */ 1007 if (!MODULE_CLASS_MATCH(mi, class)) { 1008 module_incompat(mi, class); 1009 error = ENOENT; 1010 goto fail; 1011 } 1012 1013 /* 1014 * If loading a dependency, `name' is a plain module name. 1015 * The name must match. 1016 */ 1017 if (isdep && strcmp(mi->mi_name, name) != 0) { 1018 module_error("dependency name mismatch (`%s' != `%s')", 1019 name, mi->mi_name); 1020 error = ENOENT; 1021 goto fail; 1022 } 1023 1024 /* 1025 * Check to see if the module is already loaded. If so, we may 1026 * have been recursively called to handle a dependency, so be sure 1027 * to set modp. 1028 */ 1029 if ((mod2 = module_lookup(mi->mi_name)) != NULL) { 1030 if (modp != NULL) 1031 *modp = mod2; 1032 module_print("module `%s' already loaded", mi->mi_name); 1033 error = EEXIST; 1034 goto fail; 1035 } 1036 1037 /* 1038 * Block circular dependencies. 1039 */ 1040 TAILQ_FOREACH(mod2, pending, mod_chain) { 1041 if (mod == mod2) { 1042 continue; 1043 } 1044 if (strcmp(mod2->mod_info->mi_name, mi->mi_name) == 0) { 1045 error = EDEADLK; 1046 module_error("circular dependency detected for `%s'", 1047 mi->mi_name); 1048 goto fail; 1049 } 1050 } 1051 1052 /* 1053 * Now try to load any requisite modules. 1054 */ 1055 if (mi->mi_required != NULL) { 1056 for (s = mi->mi_required; *s != '\0'; s = p) { 1057 if (*s == ',') 1058 s++; 1059 p = s; 1060 while (*p != '\0' && *p != ',') 1061 p++; 1062 len = p - s + 1; 1063 if (len >= MAXMODNAME) { 1064 error = EINVAL; 1065 module_error("required module name `%s' " 1066 "longer than %d", mi->mi_required, 1067 MAXMODNAME); 1068 goto fail; 1069 } 1070 strlcpy(buf, s, len); 1071 if (buf[0] == '\0') 1072 break; 1073 if (mod->mod_nrequired == MAXMODDEPS - 1) { 1074 error = EINVAL; 1075 module_error("too many required modules " 1076 "%d >= %d", mod->mod_nrequired, 1077 MAXMODDEPS - 1); 1078 goto fail; 1079 } 1080 if (strcmp(buf, mi->mi_name) == 0) { 1081 error = EDEADLK; 1082 module_error("self-dependency detected for " 1083 "`%s'", mi->mi_name); 1084 goto fail; 1085 } 1086 error = module_do_load(buf, true, flags, NULL, 1087 &mod2, MODULE_CLASS_ANY, true); 1088 if (error != 0) { 1089 module_error("recursive load failed for `%s', " 1090 "error %d", mi->mi_name, error); 1091 goto fail; 1092 } 1093 mod->mod_required[mod->mod_nrequired++] = mod2; 1094 } 1095 } 1096 1097 /* 1098 * We loaded all needed modules successfully: perform global 1099 * relocations and initialize. 1100 */ 1101 error = kobj_affix(mod->mod_kobj, mi->mi_name); 1102 if (error != 0) { 1103 /* Cannot touch 'mi' as the module is now gone. */ 1104 module_error("unable to affix module `%s', error %d", name, 1105 error); 1106 goto fail2; 1107 } 1108 1109 if (filedict) { 1110 if (!module_merge_dicts(filedict, props)) { 1111 module_error("module properties failed for %s", name); 1112 error = EINVAL; 1113 goto fail; 1114 } 1115 } 1116 prev_active = module_active; 1117 module_active = mod; 1118 error = (*mi->mi_modcmd)(MODULE_CMD_INIT, filedict ? filedict : props); 1119 module_active = prev_active; 1120 if (filedict) { 1121 prop_object_release(filedict); 1122 filedict = NULL; 1123 } 1124 if (error != 0) { 1125 module_error("modcmd function failed for `%s', error %d", 1126 mi->mi_name, error); 1127 goto fail; 1128 } 1129 1130 /* 1131 * Good, the module loaded successfully. Put it onto the 1132 * list and add references to its requisite modules. 1133 */ 1134 TAILQ_REMOVE(pending, mod, mod_chain); 1135 module_enqueue(mod); 1136 if (modp != NULL) { 1137 *modp = mod; 1138 } 1139 if (autoload && module_autotime > 0) { 1140 /* 1141 * Arrange to try unloading the module after 1142 * a short delay unless auto-unload is disabled. 1143 */ 1144 mod->mod_autotime = time_second + module_autotime; 1145 mod->mod_flags |= MODFLG_AUTO_LOADED; 1146 module_thread_kick(); 1147 } 1148 depth--; 1149 return 0; 1150 1151 fail: 1152 kobj_unload(mod->mod_kobj); 1153 fail2: 1154 if (filedict != NULL) { 1155 prop_object_release(filedict); 1156 filedict = NULL; 1157 } 1158 TAILQ_REMOVE(pending, mod, mod_chain); 1159 kmem_free(mod, sizeof(*mod)); 1160 depth--; 1161 return error; 1162 } 1163 1164 /* 1165 * module_do_unload: 1166 * 1167 * Helper routine: do the dirty work of unloading a module. 1168 */ 1169 static int 1170 module_do_unload(const char *name, bool load_requires_force) 1171 { 1172 module_t *mod, *prev_active; 1173 int error; 1174 u_int i; 1175 1176 KASSERT(kernconfig_is_held()); 1177 KASSERT(name != NULL); 1178 1179 mod = module_lookup(name); 1180 if (mod == NULL) { 1181 module_error("module `%s' not found", name); 1182 return ENOENT; 1183 } 1184 if (mod->mod_refcnt != 0) { 1185 module_print("module `%s' busy", name); 1186 return EBUSY; 1187 } 1188 1189 /* 1190 * Builtin secmodels are there to stay. 1191 */ 1192 if (mod->mod_source == MODULE_SOURCE_KERNEL && 1193 mod->mod_info->mi_class == MODULE_CLASS_SECMODEL) { 1194 return EPERM; 1195 } 1196 1197 prev_active = module_active; 1198 module_active = mod; 1199 error = (*mod->mod_info->mi_modcmd)(MODULE_CMD_FINI, NULL); 1200 module_active = prev_active; 1201 if (error != 0) { 1202 module_print("cannot unload module `%s' error=%d", name, 1203 error); 1204 return error; 1205 } 1206 module_count--; 1207 TAILQ_REMOVE(&module_list, mod, mod_chain); 1208 for (i = 0; i < mod->mod_nrequired; i++) { 1209 mod->mod_required[i]->mod_refcnt--; 1210 } 1211 module_print("unloaded module `%s'", name); 1212 if (mod->mod_kobj != NULL) { 1213 kobj_unload(mod->mod_kobj); 1214 } 1215 if (mod->mod_source == MODULE_SOURCE_KERNEL) { 1216 mod->mod_nrequired = 0; /* will be re-parsed */ 1217 if (load_requires_force) 1218 module_require_force(mod); 1219 TAILQ_INSERT_TAIL(&module_builtins, mod, mod_chain); 1220 module_builtinlist++; 1221 } else { 1222 kmem_free(mod, sizeof(*mod)); 1223 } 1224 module_gen++; 1225 1226 return 0; 1227 } 1228 1229 /* 1230 * module_prime: 1231 * 1232 * Push a module loaded by the bootloader onto our internal 1233 * list. 1234 */ 1235 int 1236 module_prime(const char *name, void *base, size_t size) 1237 { 1238 module_t *mod; 1239 int error; 1240 1241 mod = module_newmodule(MODULE_SOURCE_BOOT); 1242 if (mod == NULL) { 1243 return ENOMEM; 1244 } 1245 1246 error = kobj_load_mem(&mod->mod_kobj, name, base, size); 1247 if (error != 0) { 1248 kmem_free(mod, sizeof(*mod)); 1249 module_error("unable to load `%s' pushed by boot loader, " 1250 "error %d", name, error); 1251 return error; 1252 } 1253 error = module_fetch_info(mod); 1254 if (error != 0) { 1255 kobj_unload(mod->mod_kobj); 1256 kmem_free(mod, sizeof(*mod)); 1257 module_error("unable to load `%s' pushed by boot loader, " 1258 "error %d", name, error); 1259 return error; 1260 } 1261 1262 TAILQ_INSERT_TAIL(&module_bootlist, mod, mod_chain); 1263 1264 return 0; 1265 } 1266 1267 /* 1268 * module_fetch_into: 1269 * 1270 * Fetch modinfo record from a loaded module. 1271 */ 1272 static int 1273 module_fetch_info(module_t *mod) 1274 { 1275 int error; 1276 void *addr; 1277 size_t size; 1278 1279 /* 1280 * Find module info record and check compatibility. 1281 */ 1282 error = kobj_find_section(mod->mod_kobj, "link_set_modules", 1283 &addr, &size); 1284 if (error != 0) { 1285 module_error("`link_set_modules' section not present, " 1286 "error %d", error); 1287 return error; 1288 } 1289 if (size != sizeof(modinfo_t **)) { 1290 module_error("`link_set_modules' section wrong size %zu != %zu", 1291 size, sizeof(modinfo_t **)); 1292 return ENOEXEC; 1293 } 1294 mod->mod_info = *(modinfo_t **)addr; 1295 1296 return 0; 1297 } 1298 1299 /* 1300 * module_find_section: 1301 * 1302 * Allows a module that is being initialized to look up a section 1303 * within its ELF object. 1304 */ 1305 int 1306 module_find_section(const char *name, void **addr, size_t *size) 1307 { 1308 1309 KASSERT(kernconfig_is_held()); 1310 KASSERT(module_active != NULL); 1311 1312 return kobj_find_section(module_active->mod_kobj, name, addr, size); 1313 } 1314 1315 /* 1316 * module_thread: 1317 * 1318 * Automatically unload modules. We try once to unload autoloaded 1319 * modules after module_autotime seconds. If the system is under 1320 * severe memory pressure, we'll try unloading all modules, else if 1321 * module_autotime is zero, we don't try to unload, even if the 1322 * module was previously scheduled for unload. 1323 */ 1324 static void 1325 module_thread(void *cookie) 1326 { 1327 module_t *mod, *next; 1328 modinfo_t *mi; 1329 int error; 1330 1331 for (;;) { 1332 kernconfig_lock(); 1333 for (mod = TAILQ_FIRST(&module_list); mod != NULL; mod = next) { 1334 next = TAILQ_NEXT(mod, mod_chain); 1335 1336 /* skip built-in modules */ 1337 if (mod->mod_source == MODULE_SOURCE_KERNEL) 1338 continue; 1339 /* skip modules that weren't auto-loaded */ 1340 if ((mod->mod_flags & MODFLG_AUTO_LOADED) == 0) 1341 continue; 1342 1343 if (uvmexp.free < uvmexp.freemin) { 1344 module_thread_ticks = hz; 1345 } else if (module_autotime == 0 || 1346 mod->mod_autotime == 0) { 1347 continue; 1348 } else if (time_second < mod->mod_autotime) { 1349 module_thread_ticks = hz; 1350 continue; 1351 } else { 1352 mod->mod_autotime = 0; 1353 } 1354 1355 /* 1356 * If this module wants to avoid autounload then 1357 * skip it. Some modules can ping-pong in and out 1358 * because their use is transient but often. 1359 * Example: exec_script. 1360 */ 1361 mi = mod->mod_info; 1362 error = (*mi->mi_modcmd)(MODULE_CMD_AUTOUNLOAD, NULL); 1363 if (error == 0 || error == ENOTTY) { 1364 (void)module_do_unload(mi->mi_name, false); 1365 } 1366 } 1367 kernconfig_unlock(); 1368 1369 mutex_enter(&module_thread_lock); 1370 (void)cv_timedwait(&module_thread_cv, &module_thread_lock, 1371 module_thread_ticks); 1372 module_thread_ticks = 0; 1373 mutex_exit(&module_thread_lock); 1374 } 1375 } 1376 1377 /* 1378 * module_thread: 1379 * 1380 * Kick the module thread into action, perhaps because the 1381 * system is low on memory. 1382 */ 1383 void 1384 module_thread_kick(void) 1385 { 1386 1387 mutex_enter(&module_thread_lock); 1388 module_thread_ticks = hz; 1389 cv_broadcast(&module_thread_cv); 1390 mutex_exit(&module_thread_lock); 1391 } 1392 1393 #ifdef DDB 1394 /* 1395 * module_whatis: 1396 * 1397 * Helper routine for DDB. 1398 */ 1399 void 1400 module_whatis(uintptr_t addr, void (*pr)(const char *, ...)) 1401 { 1402 module_t *mod; 1403 size_t msize; 1404 vaddr_t maddr; 1405 1406 TAILQ_FOREACH(mod, &module_list, mod_chain) { 1407 if (mod->mod_kobj == NULL) { 1408 continue; 1409 } 1410 if (kobj_stat(mod->mod_kobj, &maddr, &msize) != 0) 1411 continue; 1412 if (addr < maddr || addr >= maddr + msize) { 1413 continue; 1414 } 1415 (*pr)("%p is %p+%zu, in kernel module `%s'\n", 1416 (void *)addr, (void *)maddr, 1417 (size_t)(addr - maddr), mod->mod_info->mi_name); 1418 } 1419 } 1420 1421 /* 1422 * module_print_list: 1423 * 1424 * Helper routine for DDB. 1425 */ 1426 void 1427 module_print_list(void (*pr)(const char *, ...)) 1428 { 1429 const char *src; 1430 module_t *mod; 1431 size_t msize; 1432 vaddr_t maddr; 1433 1434 (*pr)("%16s %16s %8s %8s\n", "NAME", "TEXT/DATA", "SIZE", "SOURCE"); 1435 1436 TAILQ_FOREACH(mod, &module_list, mod_chain) { 1437 switch (mod->mod_source) { 1438 case MODULE_SOURCE_KERNEL: 1439 src = "builtin"; 1440 break; 1441 case MODULE_SOURCE_FILESYS: 1442 src = "filesys"; 1443 break; 1444 case MODULE_SOURCE_BOOT: 1445 src = "boot"; 1446 break; 1447 default: 1448 src = "unknown"; 1449 break; 1450 } 1451 if (mod->mod_kobj == NULL) { 1452 maddr = 0; 1453 msize = 0; 1454 } else if (kobj_stat(mod->mod_kobj, &maddr, &msize) != 0) 1455 continue; 1456 (*pr)("%16s %16lx %8ld %8s\n", mod->mod_info->mi_name, 1457 (long)maddr, (long)msize, src); 1458 } 1459 } 1460 #endif /* DDB */ 1461 1462 static bool 1463 module_merge_dicts(prop_dictionary_t existing_dict, 1464 const prop_dictionary_t new_dict) 1465 { 1466 prop_dictionary_keysym_t props_keysym; 1467 prop_object_iterator_t props_iter; 1468 prop_object_t props_obj; 1469 const char *props_key; 1470 bool error; 1471 1472 if (new_dict == NULL) { /* nothing to merge */ 1473 return true; 1474 } 1475 1476 error = false; 1477 props_iter = prop_dictionary_iterator(new_dict); 1478 if (props_iter == NULL) { 1479 return false; 1480 } 1481 1482 while ((props_obj = prop_object_iterator_next(props_iter)) != NULL) { 1483 props_keysym = (prop_dictionary_keysym_t)props_obj; 1484 props_key = prop_dictionary_keysym_cstring_nocopy(props_keysym); 1485 props_obj = prop_dictionary_get_keysym(new_dict, props_keysym); 1486 if ((props_obj == NULL) || !prop_dictionary_set(existing_dict, 1487 props_key, props_obj)) { 1488 error = true; 1489 goto out; 1490 } 1491 } 1492 error = false; 1493 1494 out: 1495 prop_object_iterator_release(props_iter); 1496 1497 return !error; 1498 } 1499