1 /* $NetBSD: kern_module.c,v 1.125 2017/06/01 02:45:13 chs 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 1.125 2017/06/01 02:45:13 chs 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 bool module_verbose_on; 70 #ifdef MODULAR_DEFAULT_AUTOLOAD 71 bool module_autoload_on = true; 72 #else 73 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 module_t *, const char *, module_t **, 97 prop_dictionary_t); 98 static int module_fetch_info(module_t *); 99 static void module_thread(void *); 100 101 static module_t *module_lookup(const char *); 102 static void module_enqueue(module_t *); 103 104 static bool module_merge_dicts(prop_dictionary_t, const prop_dictionary_t); 105 106 static void sysctl_module_setup(void); 107 static int sysctl_module_autotime(SYSCTLFN_PROTO); 108 109 #define MODULE_CLASS_MATCH(mi, modclass) \ 110 ((modclass) == MODULE_CLASS_ANY || (modclass) == (mi)->mi_class) 111 112 static void 113 module_incompat(const modinfo_t *mi, int modclass) 114 { 115 module_error("incompatible module class for `%s' (%d != %d)", 116 mi->mi_name, modclass, mi->mi_class); 117 } 118 119 /* 120 * module_error: 121 * 122 * Utility function: log an error. 123 */ 124 void 125 module_error(const char *fmt, ...) 126 { 127 va_list ap; 128 129 va_start(ap, fmt); 130 printf("WARNING: module error: "); 131 vprintf(fmt, ap); 132 printf("\n"); 133 va_end(ap); 134 } 135 136 /* 137 * module_print: 138 * 139 * Utility function: log verbose output. 140 */ 141 void 142 module_print(const char *fmt, ...) 143 { 144 va_list ap; 145 146 if (module_verbose_on) { 147 va_start(ap, fmt); 148 printf("DEBUG: module: "); 149 vprintf(fmt, ap); 150 printf("\n"); 151 va_end(ap); 152 } 153 } 154 155 static int 156 module_listener_cb(kauth_cred_t cred, kauth_action_t action, void *cookie, 157 void *arg0, void *arg1, void *arg2, void *arg3) 158 { 159 int result; 160 161 result = KAUTH_RESULT_DEFER; 162 163 if (action != KAUTH_SYSTEM_MODULE) 164 return result; 165 166 if ((uintptr_t)arg2 != 0) /* autoload */ 167 result = KAUTH_RESULT_ALLOW; 168 169 return result; 170 } 171 172 /* 173 * Allocate a new module_t 174 */ 175 static module_t * 176 module_newmodule(modsrc_t source) 177 { 178 module_t *mod; 179 180 mod = kmem_zalloc(sizeof(*mod), KM_SLEEP); 181 mod->mod_source = source; 182 mod->mod_info = NULL; 183 mod->mod_flags = 0; 184 return mod; 185 } 186 187 /* 188 * Require the -f (force) flag to load a module 189 */ 190 static void 191 module_require_force(struct module *mod) 192 { 193 mod->mod_flags |= MODFLG_MUST_FORCE; 194 } 195 196 /* 197 * Add modules to the builtin list. This can done at boottime or 198 * at runtime if the module is linked into the kernel with an 199 * external linker. All or none of the input will be handled. 200 * Optionally, the modules can be initialized. If they are not 201 * initialized, module_init_class() or module_load() can be used 202 * later, but these are not guaranteed to give atomic results. 203 */ 204 int 205 module_builtin_add(modinfo_t *const *mip, size_t nmodinfo, bool init) 206 { 207 struct module **modp = NULL, *mod_iter; 208 int rv = 0, i, mipskip; 209 210 if (init) { 211 rv = kauth_authorize_system(kauth_cred_get(), 212 KAUTH_SYSTEM_MODULE, 0, (void *)(uintptr_t)MODCTL_LOAD, 213 (void *)(uintptr_t)1, NULL); 214 if (rv) { 215 return rv; 216 } 217 } 218 219 for (i = 0, mipskip = 0; i < nmodinfo; i++) { 220 if (mip[i] == &module_dummy) { 221 KASSERT(nmodinfo > 0); 222 nmodinfo--; 223 } 224 } 225 if (nmodinfo == 0) 226 return 0; 227 228 modp = kmem_zalloc(sizeof(*modp) * nmodinfo, KM_SLEEP); 229 for (i = 0, mipskip = 0; i < nmodinfo; i++) { 230 if (mip[i+mipskip] == &module_dummy) { 231 mipskip++; 232 continue; 233 } 234 modp[i] = module_newmodule(MODULE_SOURCE_KERNEL); 235 modp[i]->mod_info = mip[i+mipskip]; 236 } 237 kernconfig_lock(); 238 239 /* do this in three stages for error recovery and atomicity */ 240 241 /* first check for presence */ 242 for (i = 0; i < nmodinfo; i++) { 243 TAILQ_FOREACH(mod_iter, &module_builtins, mod_chain) { 244 if (strcmp(mod_iter->mod_info->mi_name, 245 modp[i]->mod_info->mi_name) == 0) 246 break; 247 } 248 if (mod_iter) { 249 rv = EEXIST; 250 goto out; 251 } 252 253 if (module_lookup(modp[i]->mod_info->mi_name) != NULL) { 254 rv = EEXIST; 255 goto out; 256 } 257 } 258 259 /* then add to list */ 260 for (i = 0; i < nmodinfo; i++) { 261 TAILQ_INSERT_TAIL(&module_builtins, modp[i], mod_chain); 262 module_builtinlist++; 263 } 264 265 /* finally, init (if required) */ 266 if (init) { 267 for (i = 0; i < nmodinfo; i++) { 268 rv = module_do_builtin(modp[i], 269 modp[i]->mod_info->mi_name, NULL, NULL); 270 /* throw in the towel, recovery hard & not worth it */ 271 if (rv) 272 panic("%s: builtin module \"%s\" init failed:" 273 " %d", __func__, 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("%s: %d", __func__, 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(mod, mi->mi_name, NULL, 510 NULL) != 0) { 511 TAILQ_REMOVE(&module_builtins, mod, mod_chain); 512 TAILQ_INSERT_TAIL(&bi_fail, mod, mod_chain); 513 } 514 break; 515 } 516 } while (mod != NULL); 517 518 /* 519 * Now preloaded modules. These will be pulled off the 520 * list as we call module_do_load(); 521 */ 522 do { 523 TAILQ_FOREACH(mod, &module_bootlist, mod_chain) { 524 mi = mod->mod_info; 525 if (!MODULE_CLASS_MATCH(mi, modclass)) 526 continue; 527 module_do_load(mi->mi_name, false, 0, NULL, NULL, 528 modclass, false); 529 break; 530 } 531 } while (mod != NULL); 532 533 /* return failed builtin modules to builtin list */ 534 while ((mod = TAILQ_FIRST(&bi_fail)) != NULL) { 535 TAILQ_REMOVE(&bi_fail, mod, mod_chain); 536 TAILQ_INSERT_TAIL(&module_builtins, mod, mod_chain); 537 } 538 539 kernconfig_unlock(); 540 } 541 542 /* 543 * module_compatible: 544 * 545 * Return true if the two supplied kernel versions are said to 546 * have the same binary interface for kernel code. The entire 547 * version is signficant for the development tree (-current), 548 * major and minor versions are significant for official 549 * releases of the system. 550 */ 551 bool 552 module_compatible(int v1, int v2) 553 { 554 555 #if __NetBSD_Version__ / 1000000 % 100 == 99 /* -current */ 556 return v1 == v2; 557 #else /* release */ 558 return abs(v1 - v2) < 10000; 559 #endif 560 } 561 562 /* 563 * module_load: 564 * 565 * Load a single module from the file system. 566 */ 567 int 568 module_load(const char *filename, int flags, prop_dictionary_t props, 569 modclass_t modclass) 570 { 571 module_t *mod; 572 int error; 573 574 /* Test if we already have the module loaded before 575 * authorizing so we have the opportunity to return EEXIST. */ 576 kernconfig_lock(); 577 mod = module_lookup(filename); 578 if (mod != NULL) { 579 module_print("%s module `%s' already loaded", 580 "requested", filename); 581 error = EEXIST; 582 goto out; 583 } 584 585 /* Authorize. */ 586 error = kauth_authorize_system(kauth_cred_get(), KAUTH_SYSTEM_MODULE, 587 0, (void *)(uintptr_t)MODCTL_LOAD, NULL, NULL); 588 if (error != 0) 589 goto out; 590 591 error = module_do_load(filename, false, flags, props, NULL, modclass, 592 false); 593 594 out: 595 kernconfig_unlock(); 596 return error; 597 } 598 599 /* 600 * module_autoload: 601 * 602 * Load a single module from the file system, system initiated. 603 */ 604 int 605 module_autoload(const char *filename, modclass_t modclass) 606 { 607 int error; 608 609 kernconfig_lock(); 610 611 /* Nothing if the user has disabled it. */ 612 if (!module_autoload_on) { 613 kernconfig_unlock(); 614 return EPERM; 615 } 616 617 /* Disallow path separators and magic symlinks. */ 618 if (strchr(filename, '/') != NULL || strchr(filename, '@') != NULL || 619 strchr(filename, '.') != NULL) { 620 kernconfig_unlock(); 621 return EPERM; 622 } 623 624 /* Authorize. */ 625 error = kauth_authorize_system(kauth_cred_get(), KAUTH_SYSTEM_MODULE, 626 0, (void *)(uintptr_t)MODCTL_LOAD, (void *)(uintptr_t)1, NULL); 627 628 if (error == 0) 629 error = module_do_load(filename, false, 0, NULL, NULL, modclass, 630 true); 631 632 kernconfig_unlock(); 633 return error; 634 } 635 636 /* 637 * module_unload: 638 * 639 * Find and unload a module by name. 640 */ 641 int 642 module_unload(const char *name) 643 { 644 int error; 645 646 /* Authorize. */ 647 error = kauth_authorize_system(kauth_cred_get(), KAUTH_SYSTEM_MODULE, 648 0, (void *)(uintptr_t)MODCTL_UNLOAD, NULL, NULL); 649 if (error != 0) { 650 return error; 651 } 652 653 kernconfig_lock(); 654 error = module_do_unload(name, true); 655 kernconfig_unlock(); 656 657 return error; 658 } 659 660 /* 661 * module_lookup: 662 * 663 * Look up a module by name. 664 */ 665 module_t * 666 module_lookup(const char *name) 667 { 668 module_t *mod; 669 670 KASSERT(kernconfig_is_held()); 671 672 TAILQ_FOREACH(mod, &module_list, mod_chain) { 673 if (strcmp(mod->mod_info->mi_name, name) == 0) { 674 break; 675 } 676 } 677 678 return mod; 679 } 680 681 /* 682 * module_hold: 683 * 684 * Add a single reference to a module. It's the caller's 685 * responsibility to ensure that the reference is dropped 686 * later. 687 */ 688 int 689 module_hold(const char *name) 690 { 691 module_t *mod; 692 693 kernconfig_lock(); 694 mod = module_lookup(name); 695 if (mod == NULL) { 696 kernconfig_unlock(); 697 return ENOENT; 698 } 699 mod->mod_refcnt++; 700 kernconfig_unlock(); 701 702 return 0; 703 } 704 705 /* 706 * module_rele: 707 * 708 * Release a reference acquired with module_hold(). 709 */ 710 void 711 module_rele(const char *name) 712 { 713 module_t *mod; 714 715 kernconfig_lock(); 716 mod = module_lookup(name); 717 if (mod == NULL) { 718 kernconfig_unlock(); 719 panic("%s: gone", __func__); 720 } 721 mod->mod_refcnt--; 722 kernconfig_unlock(); 723 } 724 725 /* 726 * module_enqueue: 727 * 728 * Put a module onto the global list and update counters. 729 */ 730 void 731 module_enqueue(module_t *mod) 732 { 733 int i; 734 735 KASSERT(kernconfig_is_held()); 736 737 /* 738 * Put new entry at the head of the queue so autounload can unload 739 * requisite modules with only one pass through the queue. 740 */ 741 TAILQ_INSERT_HEAD(&module_list, mod, mod_chain); 742 if (mod->mod_nrequired) { 743 744 /* Add references to the requisite modules. */ 745 for (i = 0; i < mod->mod_nrequired; i++) { 746 KASSERT(mod->mod_required[i] != NULL); 747 mod->mod_required[i]->mod_refcnt++; 748 } 749 } 750 module_count++; 751 module_gen++; 752 } 753 754 /* 755 * module_do_builtin: 756 * 757 * Initialize a module from the list of modules that are 758 * already linked into the kernel. 759 */ 760 static int 761 module_do_builtin(const module_t *pmod, const char *name, module_t **modp, 762 prop_dictionary_t props) 763 { 764 const char *p, *s; 765 char buf[MAXMODNAME]; 766 modinfo_t *mi = NULL; 767 module_t *mod, *mod2, *mod_loaded, *prev_active; 768 size_t len; 769 int error; 770 771 KASSERT(kernconfig_is_held()); 772 773 /* 774 * Search the list to see if we have a module by this name. 775 */ 776 TAILQ_FOREACH(mod, &module_builtins, mod_chain) { 777 if (strcmp(mod->mod_info->mi_name, name) == 0) { 778 mi = mod->mod_info; 779 break; 780 } 781 } 782 783 /* 784 * Check to see if already loaded. This might happen if we 785 * were already loaded as a dependency. 786 */ 787 if ((mod_loaded = module_lookup(name)) != NULL) { 788 KASSERT(mod == NULL); 789 if (modp) 790 *modp = mod_loaded; 791 return 0; 792 } 793 794 /* Note! This is from TAILQ, not immediate above */ 795 if (mi == NULL) { 796 /* 797 * XXX: We'd like to panic here, but currently in some 798 * cases (such as nfsserver + nfs), the dependee can be 799 * succesfully linked without the dependencies. 800 */ 801 module_error("%s: can't find builtin dependency `%s'", 802 pmod->mod_info->mi_name, name); 803 return ENOENT; 804 } 805 806 /* 807 * Initialize pre-requisites. 808 */ 809 if (mi->mi_required != NULL) { 810 for (s = mi->mi_required; *s != '\0'; s = p) { 811 if (*s == ',') 812 s++; 813 p = s; 814 while (*p != '\0' && *p != ',') 815 p++; 816 len = min(p - s + 1, sizeof(buf)); 817 strlcpy(buf, s, len); 818 if (buf[0] == '\0') 819 break; 820 if (mod->mod_nrequired == MAXMODDEPS - 1) { 821 module_error("%s: too many required modules " 822 "%d >= %d", pmod->mod_info->mi_name, 823 mod->mod_nrequired, MAXMODDEPS - 1); 824 return EINVAL; 825 } 826 error = module_do_builtin(mod, buf, &mod2, NULL); 827 if (error != 0) { 828 return error; 829 } 830 mod->mod_required[mod->mod_nrequired++] = mod2; 831 } 832 } 833 834 /* 835 * Try to initialize the module. 836 */ 837 prev_active = module_active; 838 module_active = mod; 839 error = (*mi->mi_modcmd)(MODULE_CMD_INIT, props); 840 module_active = prev_active; 841 if (error != 0) { 842 module_error("builtin module `%s' " 843 "failed to init, error %d", mi->mi_name, error); 844 return error; 845 } 846 847 /* load always succeeds after this point */ 848 849 TAILQ_REMOVE(&module_builtins, mod, mod_chain); 850 module_builtinlist--; 851 if (modp != NULL) { 852 *modp = mod; 853 } 854 module_enqueue(mod); 855 return 0; 856 } 857 858 /* 859 * module_do_load: 860 * 861 * Helper routine: load a module from the file system, or one 862 * pushed by the boot loader. 863 */ 864 static int 865 module_do_load(const char *name, bool isdep, int flags, 866 prop_dictionary_t props, module_t **modp, modclass_t modclass, 867 bool autoload) 868 { 869 #define MODULE_MAX_DEPTH 6 870 871 TAILQ_HEAD(pending_t, module); 872 static int depth = 0; 873 static struct pending_t *pending_lists[MODULE_MAX_DEPTH]; 874 struct pending_t *pending; 875 struct pending_t new_pending = TAILQ_HEAD_INITIALIZER(new_pending); 876 modinfo_t *mi; 877 module_t *mod, *mod2, *prev_active; 878 prop_dictionary_t filedict; 879 char buf[MAXMODNAME]; 880 const char *s, *p; 881 int error; 882 size_t len; 883 884 KASSERT(kernconfig_is_held()); 885 886 filedict = NULL; 887 error = 0; 888 889 /* 890 * Avoid recursing too far. 891 */ 892 if (++depth > MODULE_MAX_DEPTH) { 893 module_error("recursion too deep for `%s' %d > %d", name, 894 depth, MODULE_MAX_DEPTH); 895 depth--; 896 return EMLINK; 897 } 898 899 /* 900 * Set up the pending list for this depth. If this is a 901 * recursive entry, then use same list as for outer call, 902 * else use the locally allocated list. In either case, 903 * remember which one we're using. 904 */ 905 if (isdep) { 906 KASSERT(depth > 1); 907 pending = pending_lists[depth - 2]; 908 } else 909 pending = &new_pending; 910 pending_lists[depth - 1] = pending; 911 912 /* 913 * Search the list of disabled builtins first. 914 */ 915 TAILQ_FOREACH(mod, &module_builtins, mod_chain) { 916 if (strcmp(mod->mod_info->mi_name, name) == 0) { 917 break; 918 } 919 } 920 if (mod) { 921 if ((mod->mod_flags & MODFLG_MUST_FORCE) && 922 (flags & MODCTL_LOAD_FORCE) == 0) { 923 if (!autoload) { 924 module_error("use -f to reinstate " 925 "builtin module `%s'", name); 926 } 927 depth--; 928 return EPERM; 929 } else { 930 error = module_do_builtin(mod, name, modp, props); 931 depth--; 932 return error; 933 } 934 } 935 936 /* 937 * Load the module and link. Before going to the file system, 938 * scan the list of modules loaded by the boot loader. 939 */ 940 TAILQ_FOREACH(mod, &module_bootlist, mod_chain) { 941 if (strcmp(mod->mod_info->mi_name, name) == 0) { 942 TAILQ_REMOVE(&module_bootlist, mod, mod_chain); 943 break; 944 } 945 } 946 if (mod != NULL) { 947 TAILQ_INSERT_TAIL(pending, mod, mod_chain); 948 } else { 949 /* 950 * Check to see if module is already present. 951 */ 952 mod = module_lookup(name); 953 if (mod != NULL) { 954 if (modp != NULL) { 955 *modp = mod; 956 } 957 module_print("%s module `%s' already loaded", 958 isdep ? "dependent" : "requested", name); 959 depth--; 960 return EEXIST; 961 } 962 963 mod = module_newmodule(MODULE_SOURCE_FILESYS); 964 if (mod == NULL) { 965 module_error("out of memory for `%s'", name); 966 depth--; 967 return ENOMEM; 968 } 969 970 error = module_load_vfs_vec(name, flags, autoload, mod, 971 &filedict); 972 if (error != 0) { 973 #ifdef DEBUG 974 /* 975 * The exec class of modules contains a list of 976 * modules that is the union of all the modules 977 * available for each architecture, so we don't 978 * print an error if they are missing. 979 */ 980 if ((modclass != MODULE_CLASS_EXEC || error != ENOENT) 981 && root_device != NULL) 982 module_error("vfs load failed for `%s', " 983 "error %d", name, error); 984 #endif 985 kmem_free(mod, sizeof(*mod)); 986 depth--; 987 return error; 988 } 989 TAILQ_INSERT_TAIL(pending, mod, mod_chain); 990 991 error = module_fetch_info(mod); 992 if (error != 0) { 993 module_error("cannot fetch info for `%s', error %d", 994 name, error); 995 goto fail; 996 } 997 } 998 999 /* 1000 * Check compatibility. 1001 */ 1002 mi = mod->mod_info; 1003 if (strlen(mi->mi_name) >= MAXMODNAME) { 1004 error = EINVAL; 1005 module_error("module name `%s' longer than %d", mi->mi_name, 1006 MAXMODNAME); 1007 goto fail; 1008 } 1009 if (!module_compatible(mi->mi_version, __NetBSD_Version__)) { 1010 module_error("module `%s' built for `%d', system `%d'", 1011 mi->mi_name, mi->mi_version, __NetBSD_Version__); 1012 if ((flags & MODCTL_LOAD_FORCE) != 0) { 1013 module_error("forced load, system may be unstable"); 1014 } else { 1015 error = EPROGMISMATCH; 1016 goto fail; 1017 } 1018 } 1019 1020 /* 1021 * If a specific kind of module was requested, ensure that we have 1022 * a match. 1023 */ 1024 if (!MODULE_CLASS_MATCH(mi, modclass)) { 1025 module_incompat(mi, modclass); 1026 error = ENOENT; 1027 goto fail; 1028 } 1029 1030 /* 1031 * If loading a dependency, `name' is a plain module name. 1032 * The name must match. 1033 */ 1034 if (isdep && strcmp(mi->mi_name, name) != 0) { 1035 module_error("dependency name mismatch (`%s' != `%s')", 1036 name, mi->mi_name); 1037 error = ENOENT; 1038 goto fail; 1039 } 1040 1041 /* 1042 * Block circular dependencies. 1043 */ 1044 TAILQ_FOREACH(mod2, pending, mod_chain) { 1045 if (mod == mod2) { 1046 continue; 1047 } 1048 if (strcmp(mod2->mod_info->mi_name, mi->mi_name) == 0) { 1049 error = EDEADLK; 1050 module_error("circular dependency detected for `%s'", 1051 mi->mi_name); 1052 goto fail; 1053 } 1054 } 1055 1056 /* 1057 * Now try to load any requisite modules. 1058 */ 1059 if (mi->mi_required != NULL) { 1060 for (s = mi->mi_required; *s != '\0'; s = p) { 1061 if (*s == ',') 1062 s++; 1063 p = s; 1064 while (*p != '\0' && *p != ',') 1065 p++; 1066 len = p - s + 1; 1067 if (len >= MAXMODNAME) { 1068 error = EINVAL; 1069 module_error("required module name `%s' " 1070 "longer than %d", mi->mi_required, 1071 MAXMODNAME); 1072 goto fail; 1073 } 1074 strlcpy(buf, s, len); 1075 if (buf[0] == '\0') 1076 break; 1077 if (mod->mod_nrequired == MAXMODDEPS - 1) { 1078 error = EINVAL; 1079 module_error("too many required modules " 1080 "%d >= %d", mod->mod_nrequired, 1081 MAXMODDEPS - 1); 1082 goto fail; 1083 } 1084 if (strcmp(buf, mi->mi_name) == 0) { 1085 error = EDEADLK; 1086 module_error("self-dependency detected for " 1087 "`%s'", mi->mi_name); 1088 goto fail; 1089 } 1090 error = module_do_load(buf, true, flags, NULL, 1091 &mod2, MODULE_CLASS_ANY, true); 1092 if (error != 0 && error != EEXIST) { 1093 module_error("recursive load failed for `%s' " 1094 "(`%s' required), error %d", mi->mi_name, 1095 buf, error); 1096 goto fail; 1097 } 1098 mod->mod_required[mod->mod_nrequired++] = mod2; 1099 } 1100 } 1101 1102 /* 1103 * We loaded all needed modules successfully: perform global 1104 * relocations and initialize. 1105 */ 1106 error = kobj_affix(mod->mod_kobj, mi->mi_name); 1107 if (error != 0) { 1108 /* Cannot touch 'mi' as the module is now gone. */ 1109 module_error("unable to affix module `%s', error %d", name, 1110 error); 1111 goto fail2; 1112 } 1113 1114 if (filedict) { 1115 if (!module_merge_dicts(filedict, props)) { 1116 module_error("module properties failed for %s", name); 1117 error = EINVAL; 1118 goto fail; 1119 } 1120 } 1121 prev_active = module_active; 1122 module_active = mod; 1123 error = (*mi->mi_modcmd)(MODULE_CMD_INIT, filedict ? filedict : props); 1124 module_active = prev_active; 1125 if (filedict) { 1126 prop_object_release(filedict); 1127 filedict = NULL; 1128 } 1129 if (error != 0) { 1130 module_error("modcmd function failed for `%s', error %d", 1131 mi->mi_name, error); 1132 goto fail; 1133 } 1134 1135 /* 1136 * Good, the module loaded successfully. Put it onto the 1137 * list and add references to its requisite modules. 1138 */ 1139 TAILQ_REMOVE(pending, mod, mod_chain); 1140 module_enqueue(mod); 1141 if (modp != NULL) { 1142 *modp = mod; 1143 } 1144 if (autoload && module_autotime > 0) { 1145 /* 1146 * Arrange to try unloading the module after 1147 * a short delay unless auto-unload is disabled. 1148 */ 1149 mod->mod_autotime = time_second + module_autotime; 1150 mod->mod_flags |= MODFLG_AUTO_LOADED; 1151 module_thread_kick(); 1152 } 1153 depth--; 1154 module_print("module `%s' loaded successfully", mi->mi_name); 1155 return 0; 1156 1157 fail: 1158 kobj_unload(mod->mod_kobj); 1159 fail2: 1160 if (filedict != NULL) { 1161 prop_object_release(filedict); 1162 filedict = NULL; 1163 } 1164 TAILQ_REMOVE(pending, mod, mod_chain); 1165 kmem_free(mod, sizeof(*mod)); 1166 depth--; 1167 return error; 1168 } 1169 1170 /* 1171 * module_do_unload: 1172 * 1173 * Helper routine: do the dirty work of unloading a module. 1174 */ 1175 static int 1176 module_do_unload(const char *name, bool load_requires_force) 1177 { 1178 module_t *mod, *prev_active; 1179 int error; 1180 u_int i; 1181 1182 KASSERT(kernconfig_is_held()); 1183 KASSERT(name != NULL); 1184 1185 module_print("unload requested for '%s' (%s)", name, 1186 load_requires_force ? "TRUE" : "FALSE"); 1187 mod = module_lookup(name); 1188 if (mod == NULL) { 1189 module_error("module `%s' not found", name); 1190 return ENOENT; 1191 } 1192 if (mod->mod_refcnt != 0) { 1193 module_print("module `%s' busy (%d refs)", name, 1194 mod->mod_refcnt); 1195 return EBUSY; 1196 } 1197 1198 /* 1199 * Builtin secmodels are there to stay. 1200 */ 1201 if (mod->mod_source == MODULE_SOURCE_KERNEL && 1202 mod->mod_info->mi_class == MODULE_CLASS_SECMODEL) { 1203 module_print("cannot unload built-in secmodel module `%s'", 1204 name); 1205 return EPERM; 1206 } 1207 1208 prev_active = module_active; 1209 module_active = mod; 1210 error = (*mod->mod_info->mi_modcmd)(MODULE_CMD_FINI, NULL); 1211 module_active = prev_active; 1212 if (error != 0) { 1213 module_print("cannot unload module `%s' error=%d", name, 1214 error); 1215 return error; 1216 } 1217 module_count--; 1218 TAILQ_REMOVE(&module_list, mod, mod_chain); 1219 for (i = 0; i < mod->mod_nrequired; i++) { 1220 mod->mod_required[i]->mod_refcnt--; 1221 } 1222 module_print("unloaded module `%s'", name); 1223 if (mod->mod_kobj != NULL) { 1224 kobj_unload(mod->mod_kobj); 1225 } 1226 if (mod->mod_source == MODULE_SOURCE_KERNEL) { 1227 mod->mod_nrequired = 0; /* will be re-parsed */ 1228 if (load_requires_force) 1229 module_require_force(mod); 1230 TAILQ_INSERT_TAIL(&module_builtins, mod, mod_chain); 1231 module_builtinlist++; 1232 } else { 1233 kmem_free(mod, sizeof(*mod)); 1234 } 1235 module_gen++; 1236 1237 return 0; 1238 } 1239 1240 /* 1241 * module_prime: 1242 * 1243 * Push a module loaded by the bootloader onto our internal 1244 * list. 1245 */ 1246 int 1247 module_prime(const char *name, void *base, size_t size) 1248 { 1249 __link_set_decl(modules, modinfo_t); 1250 modinfo_t *const *mip; 1251 module_t *mod; 1252 int error; 1253 1254 /* Check for module name same as a built-in module */ 1255 1256 __link_set_foreach(mip, modules) { 1257 if (*mip == &module_dummy) 1258 continue; 1259 if (strcmp((*mip)->mi_name, name) == 0) { 1260 module_error("module `%s' pushed by boot loader " 1261 "already exists", name); 1262 return EEXIST; 1263 } 1264 } 1265 1266 /* Also eliminate duplicate boolist entries */ 1267 1268 TAILQ_FOREACH(mod, &module_bootlist, mod_chain) { 1269 if (strcmp(mod->mod_info->mi_name, name) == 0) { 1270 module_error("duplicate bootlist entry for module " 1271 "`%s'", name); 1272 return EEXIST; 1273 } 1274 } 1275 1276 mod = module_newmodule(MODULE_SOURCE_BOOT); 1277 if (mod == NULL) { 1278 return ENOMEM; 1279 } 1280 1281 error = kobj_load_mem(&mod->mod_kobj, name, base, size); 1282 if (error != 0) { 1283 kmem_free(mod, sizeof(*mod)); 1284 module_error("unable to load `%s' pushed by boot loader, " 1285 "error %d", name, error); 1286 return error; 1287 } 1288 error = module_fetch_info(mod); 1289 if (error != 0) { 1290 kobj_unload(mod->mod_kobj); 1291 kmem_free(mod, sizeof(*mod)); 1292 module_error("unable to fetch_info for `%s' pushed by boot " 1293 "loader, error %d", name, error); 1294 return error; 1295 } 1296 1297 TAILQ_INSERT_TAIL(&module_bootlist, mod, mod_chain); 1298 1299 return 0; 1300 } 1301 1302 /* 1303 * module_fetch_into: 1304 * 1305 * Fetch modinfo record from a loaded module. 1306 */ 1307 static int 1308 module_fetch_info(module_t *mod) 1309 { 1310 int error; 1311 void *addr; 1312 size_t size; 1313 1314 /* 1315 * Find module info record and check compatibility. 1316 */ 1317 error = kobj_find_section(mod->mod_kobj, "link_set_modules", 1318 &addr, &size); 1319 if (error != 0) { 1320 module_error("`link_set_modules' section not present, " 1321 "error %d", error); 1322 return error; 1323 } 1324 if (size != sizeof(modinfo_t **)) { 1325 module_error("`link_set_modules' section wrong size %zu != %zu", 1326 size, sizeof(modinfo_t **)); 1327 return ENOEXEC; 1328 } 1329 mod->mod_info = *(modinfo_t **)addr; 1330 1331 return 0; 1332 } 1333 1334 /* 1335 * module_find_section: 1336 * 1337 * Allows a module that is being initialized to look up a section 1338 * within its ELF object. 1339 */ 1340 int 1341 module_find_section(const char *name, void **addr, size_t *size) 1342 { 1343 1344 KASSERT(kernconfig_is_held()); 1345 KASSERT(module_active != NULL); 1346 1347 return kobj_find_section(module_active->mod_kobj, name, addr, size); 1348 } 1349 1350 /* 1351 * module_thread: 1352 * 1353 * Automatically unload modules. We try once to unload autoloaded 1354 * modules after module_autotime seconds. If the system is under 1355 * severe memory pressure, we'll try unloading all modules, else if 1356 * module_autotime is zero, we don't try to unload, even if the 1357 * module was previously scheduled for unload. 1358 */ 1359 static void 1360 module_thread(void *cookie) 1361 { 1362 module_t *mod, *next; 1363 modinfo_t *mi; 1364 int error; 1365 1366 for (;;) { 1367 kernconfig_lock(); 1368 for (mod = TAILQ_FIRST(&module_list); mod != NULL; mod = next) { 1369 next = TAILQ_NEXT(mod, mod_chain); 1370 1371 /* skip built-in modules */ 1372 if (mod->mod_source == MODULE_SOURCE_KERNEL) 1373 continue; 1374 /* skip modules that weren't auto-loaded */ 1375 if ((mod->mod_flags & MODFLG_AUTO_LOADED) == 0) 1376 continue; 1377 1378 if (uvmexp.free < uvmexp.freemin) { 1379 module_thread_ticks = hz; 1380 } else if (module_autotime == 0 || 1381 mod->mod_autotime == 0) { 1382 continue; 1383 } else if (time_second < mod->mod_autotime) { 1384 module_thread_ticks = hz; 1385 continue; 1386 } else { 1387 mod->mod_autotime = 0; 1388 } 1389 1390 /* 1391 * If this module wants to avoid autounload then 1392 * skip it. Some modules can ping-pong in and out 1393 * because their use is transient but often. 1394 * Example: exec_script. 1395 */ 1396 mi = mod->mod_info; 1397 error = (*mi->mi_modcmd)(MODULE_CMD_AUTOUNLOAD, NULL); 1398 if (error == 0 || error == ENOTTY) { 1399 (void)module_do_unload(mi->mi_name, false); 1400 } else 1401 module_print("module `%s' declined to be " 1402 "auto-unloaded error=%d", mi->mi_name, 1403 error); 1404 } 1405 kernconfig_unlock(); 1406 1407 mutex_enter(&module_thread_lock); 1408 (void)cv_timedwait(&module_thread_cv, &module_thread_lock, 1409 module_thread_ticks); 1410 module_thread_ticks = 0; 1411 mutex_exit(&module_thread_lock); 1412 } 1413 } 1414 1415 /* 1416 * module_thread: 1417 * 1418 * Kick the module thread into action, perhaps because the 1419 * system is low on memory. 1420 */ 1421 void 1422 module_thread_kick(void) 1423 { 1424 1425 mutex_enter(&module_thread_lock); 1426 module_thread_ticks = hz; 1427 cv_broadcast(&module_thread_cv); 1428 mutex_exit(&module_thread_lock); 1429 } 1430 1431 #ifdef DDB 1432 /* 1433 * module_whatis: 1434 * 1435 * Helper routine for DDB. 1436 */ 1437 void 1438 module_whatis(uintptr_t addr, void (*pr)(const char *, ...)) 1439 { 1440 module_t *mod; 1441 size_t msize; 1442 vaddr_t maddr; 1443 1444 TAILQ_FOREACH(mod, &module_list, mod_chain) { 1445 if (mod->mod_kobj == NULL) { 1446 continue; 1447 } 1448 if (kobj_stat(mod->mod_kobj, &maddr, &msize) != 0) 1449 continue; 1450 if (addr < maddr || addr >= maddr + msize) { 1451 continue; 1452 } 1453 (*pr)("%p is %p+%zu, in kernel module `%s'\n", 1454 (void *)addr, (void *)maddr, 1455 (size_t)(addr - maddr), mod->mod_info->mi_name); 1456 } 1457 } 1458 1459 /* 1460 * module_print_list: 1461 * 1462 * Helper routine for DDB. 1463 */ 1464 void 1465 module_print_list(void (*pr)(const char *, ...)) 1466 { 1467 const char *src; 1468 module_t *mod; 1469 size_t msize; 1470 vaddr_t maddr; 1471 1472 (*pr)("%16s %16s %8s %8s\n", "NAME", "TEXT/DATA", "SIZE", "SOURCE"); 1473 1474 TAILQ_FOREACH(mod, &module_list, mod_chain) { 1475 switch (mod->mod_source) { 1476 case MODULE_SOURCE_KERNEL: 1477 src = "builtin"; 1478 break; 1479 case MODULE_SOURCE_FILESYS: 1480 src = "filesys"; 1481 break; 1482 case MODULE_SOURCE_BOOT: 1483 src = "boot"; 1484 break; 1485 default: 1486 src = "unknown"; 1487 break; 1488 } 1489 if (mod->mod_kobj == NULL) { 1490 maddr = 0; 1491 msize = 0; 1492 } else if (kobj_stat(mod->mod_kobj, &maddr, &msize) != 0) 1493 continue; 1494 (*pr)("%16s %16lx %8ld %8s\n", mod->mod_info->mi_name, 1495 (long)maddr, (long)msize, src); 1496 } 1497 } 1498 #endif /* DDB */ 1499 1500 static bool 1501 module_merge_dicts(prop_dictionary_t existing_dict, 1502 const prop_dictionary_t new_dict) 1503 { 1504 prop_dictionary_keysym_t props_keysym; 1505 prop_object_iterator_t props_iter; 1506 prop_object_t props_obj; 1507 const char *props_key; 1508 bool error; 1509 1510 if (new_dict == NULL) { /* nothing to merge */ 1511 return true; 1512 } 1513 1514 error = false; 1515 props_iter = prop_dictionary_iterator(new_dict); 1516 if (props_iter == NULL) { 1517 return false; 1518 } 1519 1520 while ((props_obj = prop_object_iterator_next(props_iter)) != NULL) { 1521 props_keysym = (prop_dictionary_keysym_t)props_obj; 1522 props_key = prop_dictionary_keysym_cstring_nocopy(props_keysym); 1523 props_obj = prop_dictionary_get_keysym(new_dict, props_keysym); 1524 if ((props_obj == NULL) || !prop_dictionary_set(existing_dict, 1525 props_key, props_obj)) { 1526 error = true; 1527 goto out; 1528 } 1529 } 1530 error = false; 1531 1532 out: 1533 prop_object_iterator_release(props_iter); 1534 1535 return !error; 1536 } 1537