1 /* $NetBSD: kern_module.c,v 1.118 2016/12/09 13:06:41 roy 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 1.118 2016/12/09 13:06:41 roy 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 if (mod != NULL) { 182 mod->mod_source = source; 183 mod->mod_info = NULL; 184 mod->mod_flags = 0; 185 } 186 return mod; 187 } 188 189 /* 190 * Require the -f (force) flag to load a module 191 */ 192 static void 193 module_require_force(struct module *mod) 194 { 195 mod->mod_flags |= MODFLG_MUST_FORCE; 196 } 197 198 /* 199 * Add modules to the builtin list. This can done at boottime or 200 * at runtime if the module is linked into the kernel with an 201 * external linker. All or none of the input will be handled. 202 * Optionally, the modules can be initialized. If they are not 203 * initialized, module_init_class() or module_load() can be used 204 * later, but these are not guaranteed to give atomic results. 205 */ 206 int 207 module_builtin_add(modinfo_t *const *mip, size_t nmodinfo, bool init) 208 { 209 struct module **modp = NULL, *mod_iter; 210 int rv = 0, i, mipskip; 211 212 if (init) { 213 rv = kauth_authorize_system(kauth_cred_get(), 214 KAUTH_SYSTEM_MODULE, 0, (void *)(uintptr_t)MODCTL_LOAD, 215 (void *)(uintptr_t)1, NULL); 216 if (rv) { 217 return rv; 218 } 219 } 220 221 for (i = 0, mipskip = 0; i < nmodinfo; i++) { 222 if (mip[i] == &module_dummy) { 223 KASSERT(nmodinfo > 0); 224 nmodinfo--; 225 } 226 } 227 if (nmodinfo == 0) 228 return 0; 229 230 modp = kmem_zalloc(sizeof(*modp) * nmodinfo, KM_SLEEP); 231 for (i = 0, mipskip = 0; i < nmodinfo; i++) { 232 if (mip[i+mipskip] == &module_dummy) { 233 mipskip++; 234 continue; 235 } 236 modp[i] = module_newmodule(MODULE_SOURCE_KERNEL); 237 modp[i]->mod_info = mip[i+mipskip]; 238 } 239 kernconfig_lock(); 240 241 /* do this in three stages for error recovery and atomicity */ 242 243 /* first check for presence */ 244 for (i = 0; i < nmodinfo; i++) { 245 TAILQ_FOREACH(mod_iter, &module_builtins, mod_chain) { 246 if (strcmp(mod_iter->mod_info->mi_name, 247 modp[i]->mod_info->mi_name) == 0) 248 break; 249 } 250 if (mod_iter) { 251 rv = EEXIST; 252 goto out; 253 } 254 255 if (module_lookup(modp[i]->mod_info->mi_name) != NULL) { 256 rv = EEXIST; 257 goto out; 258 } 259 } 260 261 /* then add to list */ 262 for (i = 0; i < nmodinfo; i++) { 263 TAILQ_INSERT_TAIL(&module_builtins, modp[i], mod_chain); 264 module_builtinlist++; 265 } 266 267 /* finally, init (if required) */ 268 if (init) { 269 for (i = 0; i < nmodinfo; i++) { 270 rv = module_do_builtin(modp[i], 271 modp[i]->mod_info->mi_name, NULL, NULL); 272 /* throw in the towel, recovery hard & not worth it */ 273 if (rv) 274 panic("%s: builtin module \"%s\" init failed:" 275 " %d", __func__, 276 modp[i]->mod_info->mi_name, rv); 277 } 278 } 279 280 out: 281 kernconfig_unlock(); 282 if (rv != 0) { 283 for (i = 0; i < nmodinfo; i++) { 284 if (modp[i]) 285 kmem_free(modp[i], sizeof(*modp[i])); 286 } 287 } 288 kmem_free(modp, sizeof(*modp) * nmodinfo); 289 return rv; 290 } 291 292 /* 293 * Optionally fini and remove builtin module from the kernel. 294 * Note: the module will now be unreachable except via mi && builtin_add. 295 */ 296 int 297 module_builtin_remove(modinfo_t *mi, bool fini) 298 { 299 struct module *mod; 300 int rv = 0; 301 302 if (fini) { 303 rv = kauth_authorize_system(kauth_cred_get(), 304 KAUTH_SYSTEM_MODULE, 0, (void *)(uintptr_t)MODCTL_UNLOAD, 305 NULL, NULL); 306 if (rv) 307 return rv; 308 309 kernconfig_lock(); 310 rv = module_do_unload(mi->mi_name, true); 311 if (rv) { 312 goto out; 313 } 314 } else { 315 kernconfig_lock(); 316 } 317 TAILQ_FOREACH(mod, &module_builtins, mod_chain) { 318 if (strcmp(mod->mod_info->mi_name, mi->mi_name) == 0) 319 break; 320 } 321 if (mod) { 322 TAILQ_REMOVE(&module_builtins, mod, mod_chain); 323 module_builtinlist--; 324 } else { 325 KASSERT(fini == false); 326 rv = ENOENT; 327 } 328 329 out: 330 kernconfig_unlock(); 331 return rv; 332 } 333 334 /* 335 * module_init: 336 * 337 * Initialize the module subsystem. 338 */ 339 void 340 module_init(void) 341 { 342 __link_set_decl(modules, modinfo_t); 343 extern struct vm_map *module_map; 344 modinfo_t *const *mip; 345 int rv; 346 347 if (module_map == NULL) { 348 module_map = kernel_map; 349 } 350 cv_init(&module_thread_cv, "mod_unld"); 351 mutex_init(&module_thread_lock, MUTEX_DEFAULT, IPL_NONE); 352 353 #ifdef MODULAR /* XXX */ 354 module_init_md(); 355 #endif 356 357 if (!module_machine) 358 module_machine = machine; 359 #if __NetBSD_Version__ / 1000000 % 100 == 99 /* -current */ 360 snprintf(module_base, sizeof(module_base), "/stand/%s/%s/modules", 361 module_machine, osrelease); 362 #else /* release */ 363 snprintf(module_base, sizeof(module_base), "/stand/%s/%d.%d/modules", 364 module_machine, __NetBSD_Version__ / 100000000, 365 __NetBSD_Version__ / 1000000 % 100); 366 #endif 367 368 module_listener = kauth_listen_scope(KAUTH_SCOPE_SYSTEM, 369 module_listener_cb, NULL); 370 371 __link_set_foreach(mip, modules) { 372 if ((rv = module_builtin_add(mip, 1, false)) != 0) 373 module_error("builtin %s failed: %d\n", 374 (*mip)->mi_name, rv); 375 } 376 377 sysctl_module_setup(); 378 } 379 380 /* 381 * module_start_unload_thread: 382 * 383 * Start the auto unload kthread. 384 */ 385 void 386 module_start_unload_thread(void) 387 { 388 int error; 389 390 error = kthread_create(PRI_VM, KTHREAD_MPSAFE, NULL, module_thread, 391 NULL, NULL, "modunload"); 392 if (error != 0) 393 panic("%s: %d", __func__, error); 394 } 395 396 /* 397 * module_builtin_require_force 398 * 399 * Require MODCTL_MUST_FORCE to load any built-in modules that have 400 * not yet been initialized 401 */ 402 void 403 module_builtin_require_force(void) 404 { 405 module_t *mod; 406 407 kernconfig_lock(); 408 TAILQ_FOREACH(mod, &module_builtins, mod_chain) { 409 module_require_force(mod); 410 } 411 kernconfig_unlock(); 412 } 413 414 static struct sysctllog *module_sysctllog; 415 416 static int 417 sysctl_module_autotime(SYSCTLFN_ARGS) 418 { 419 struct sysctlnode node; 420 int t, error; 421 422 t = *(int *)rnode->sysctl_data; 423 424 node = *rnode; 425 node.sysctl_data = &t; 426 error = sysctl_lookup(SYSCTLFN_CALL(&node)); 427 if (error || newp == NULL) 428 return (error); 429 430 if (t < 0) 431 return (EINVAL); 432 433 *(int *)rnode->sysctl_data = t; 434 return (0); 435 } 436 437 static void 438 sysctl_module_setup(void) 439 { 440 const struct sysctlnode *node = NULL; 441 442 sysctl_createv(&module_sysctllog, 0, NULL, &node, 443 CTLFLAG_PERMANENT, 444 CTLTYPE_NODE, "module", 445 SYSCTL_DESCR("Module options"), 446 NULL, 0, NULL, 0, 447 CTL_KERN, CTL_CREATE, CTL_EOL); 448 449 if (node == NULL) 450 return; 451 452 sysctl_createv(&module_sysctllog, 0, &node, NULL, 453 CTLFLAG_PERMANENT | CTLFLAG_READWRITE, 454 CTLTYPE_BOOL, "autoload", 455 SYSCTL_DESCR("Enable automatic load of modules"), 456 NULL, 0, &module_autoload_on, 0, 457 CTL_CREATE, CTL_EOL); 458 sysctl_createv(&module_sysctllog, 0, &node, NULL, 459 CTLFLAG_PERMANENT | CTLFLAG_READWRITE, 460 CTLTYPE_BOOL, "verbose", 461 SYSCTL_DESCR("Enable verbose output"), 462 NULL, 0, &module_verbose_on, 0, 463 CTL_CREATE, CTL_EOL); 464 sysctl_createv(&module_sysctllog, 0, &node, NULL, 465 CTLFLAG_PERMANENT | CTLFLAG_READONLY, 466 CTLTYPE_STRING, "path", 467 SYSCTL_DESCR("Default module load path"), 468 NULL, 0, module_base, 0, 469 CTL_CREATE, CTL_EOL); 470 sysctl_createv(&module_sysctllog, 0, &node, NULL, 471 CTLFLAG_PERMANENT | CTLFLAG_READWRITE, 472 CTLTYPE_INT, "autotime", 473 SYSCTL_DESCR("Auto-unload delay"), 474 sysctl_module_autotime, 0, &module_autotime, 0, 475 CTL_CREATE, CTL_EOL); 476 } 477 478 /* 479 * module_init_class: 480 * 481 * Initialize all built-in and pre-loaded modules of the 482 * specified class. 483 */ 484 void 485 module_init_class(modclass_t modclass) 486 { 487 TAILQ_HEAD(, module) bi_fail = TAILQ_HEAD_INITIALIZER(bi_fail); 488 module_t *mod; 489 modinfo_t *mi; 490 491 kernconfig_lock(); 492 /* 493 * Builtins first. These will not depend on pre-loaded modules 494 * (because the kernel would not link). 495 */ 496 do { 497 TAILQ_FOREACH(mod, &module_builtins, mod_chain) { 498 mi = mod->mod_info; 499 if (!MODULE_CLASS_MATCH(mi, modclass)) 500 continue; 501 /* 502 * If initializing a builtin module fails, don't try 503 * to load it again. But keep it around and queue it 504 * on the builtins list after we're done with module 505 * init. Don't set it to MODFLG_MUST_FORCE in case a 506 * future attempt to initialize can be successful. 507 * (If the module has previously been set to 508 * MODFLG_MUST_FORCE, don't try to override that!) 509 */ 510 if ((mod->mod_flags & MODFLG_MUST_FORCE) || 511 module_do_builtin(mod, mi->mi_name, NULL, 512 NULL) != 0) { 513 TAILQ_REMOVE(&module_builtins, mod, mod_chain); 514 TAILQ_INSERT_TAIL(&bi_fail, mod, mod_chain); 515 } 516 break; 517 } 518 } while (mod != NULL); 519 520 /* 521 * Now preloaded modules. These will be pulled off the 522 * list as we call module_do_load(); 523 */ 524 do { 525 TAILQ_FOREACH(mod, &module_bootlist, mod_chain) { 526 mi = mod->mod_info; 527 if (!MODULE_CLASS_MATCH(mi, modclass)) 528 continue; 529 module_do_load(mi->mi_name, false, 0, NULL, NULL, 530 modclass, false); 531 break; 532 } 533 } while (mod != NULL); 534 535 /* return failed builtin modules to builtin list */ 536 while ((mod = TAILQ_FIRST(&bi_fail)) != NULL) { 537 TAILQ_REMOVE(&bi_fail, mod, mod_chain); 538 TAILQ_INSERT_TAIL(&module_builtins, mod, mod_chain); 539 } 540 541 kernconfig_unlock(); 542 } 543 544 /* 545 * module_compatible: 546 * 547 * Return true if the two supplied kernel versions are said to 548 * have the same binary interface for kernel code. The entire 549 * version is signficant for the development tree (-current), 550 * major and minor versions are significant for official 551 * releases of the system. 552 */ 553 bool 554 module_compatible(int v1, int v2) 555 { 556 557 #if __NetBSD_Version__ / 1000000 % 100 == 99 /* -current */ 558 return v1 == v2; 559 #else /* release */ 560 return abs(v1 - v2) < 10000; 561 #endif 562 } 563 564 /* 565 * module_load: 566 * 567 * Load a single module from the file system. 568 */ 569 int 570 module_load(const char *filename, int flags, prop_dictionary_t props, 571 modclass_t modclass) 572 { 573 module_t *mod; 574 int error; 575 576 /* Test if we already have the module loaded before 577 * authorizing so we have the opportunity to return EEXIST. */ 578 kernconfig_lock(); 579 mod = module_lookup(filename); 580 if (mod != NULL) { 581 module_print("%s module `%s' already loaded", 582 "requested", filename); 583 error = EEXIST; 584 goto out; 585 } 586 587 /* Authorize. */ 588 error = kauth_authorize_system(kauth_cred_get(), KAUTH_SYSTEM_MODULE, 589 0, (void *)(uintptr_t)MODCTL_LOAD, NULL, NULL); 590 if (error != 0) 591 goto out; 592 593 error = module_do_load(filename, false, flags, props, NULL, modclass, 594 false); 595 596 out: 597 kernconfig_unlock(); 598 return error; 599 } 600 601 /* 602 * module_autoload: 603 * 604 * Load a single module from the file system, system initiated. 605 */ 606 int 607 module_autoload(const char *filename, modclass_t modclass) 608 { 609 int error; 610 611 kernconfig_lock(); 612 613 /* Nothing if the user has disabled it. */ 614 if (!module_autoload_on) { 615 kernconfig_unlock(); 616 return EPERM; 617 } 618 619 /* Disallow path separators and magic symlinks. */ 620 if (strchr(filename, '/') != NULL || strchr(filename, '@') != NULL || 621 strchr(filename, '.') != NULL) { 622 kernconfig_unlock(); 623 return EPERM; 624 } 625 626 /* Authorize. */ 627 error = kauth_authorize_system(kauth_cred_get(), KAUTH_SYSTEM_MODULE, 628 0, (void *)(uintptr_t)MODCTL_LOAD, (void *)(uintptr_t)1, NULL); 629 630 if (error == 0) 631 error = module_do_load(filename, false, 0, NULL, NULL, modclass, 632 true); 633 634 kernconfig_unlock(); 635 return error; 636 } 637 638 /* 639 * module_unload: 640 * 641 * Find and unload a module by name. 642 */ 643 int 644 module_unload(const char *name) 645 { 646 int error; 647 648 /* Authorize. */ 649 error = kauth_authorize_system(kauth_cred_get(), KAUTH_SYSTEM_MODULE, 650 0, (void *)(uintptr_t)MODCTL_UNLOAD, NULL, NULL); 651 if (error != 0) { 652 return error; 653 } 654 655 kernconfig_lock(); 656 error = module_do_unload(name, true); 657 kernconfig_unlock(); 658 659 return error; 660 } 661 662 /* 663 * module_lookup: 664 * 665 * Look up a module by name. 666 */ 667 module_t * 668 module_lookup(const char *name) 669 { 670 module_t *mod; 671 672 KASSERT(kernconfig_is_held()); 673 674 TAILQ_FOREACH(mod, &module_list, mod_chain) { 675 if (strcmp(mod->mod_info->mi_name, name) == 0) { 676 break; 677 } 678 } 679 680 return mod; 681 } 682 683 /* 684 * module_hold: 685 * 686 * Add a single reference to a module. It's the caller's 687 * responsibility to ensure that the reference is dropped 688 * later. 689 */ 690 int 691 module_hold(const char *name) 692 { 693 module_t *mod; 694 695 kernconfig_lock(); 696 mod = module_lookup(name); 697 if (mod == NULL) { 698 kernconfig_unlock(); 699 return ENOENT; 700 } 701 mod->mod_refcnt++; 702 kernconfig_unlock(); 703 704 return 0; 705 } 706 707 /* 708 * module_rele: 709 * 710 * Release a reference acquired with module_hold(). 711 */ 712 void 713 module_rele(const char *name) 714 { 715 module_t *mod; 716 717 kernconfig_lock(); 718 mod = module_lookup(name); 719 if (mod == NULL) { 720 kernconfig_unlock(); 721 panic("%s: gone", __func__); 722 } 723 mod->mod_refcnt--; 724 kernconfig_unlock(); 725 } 726 727 /* 728 * module_enqueue: 729 * 730 * Put a module onto the global list and update counters. 731 */ 732 void 733 module_enqueue(module_t *mod) 734 { 735 int i; 736 737 KASSERT(kernconfig_is_held()); 738 739 /* 740 * Put new entry at the head of the queue so autounload can unload 741 * requisite modules with only one pass through the queue. 742 */ 743 TAILQ_INSERT_HEAD(&module_list, mod, mod_chain); 744 if (mod->mod_nrequired) { 745 746 /* Add references to the requisite modules. */ 747 for (i = 0; i < mod->mod_nrequired; i++) { 748 KASSERT(mod->mod_required[i] != NULL); 749 mod->mod_required[i]->mod_refcnt++; 750 } 751 } 752 module_count++; 753 module_gen++; 754 } 755 756 /* 757 * module_do_builtin: 758 * 759 * Initialize a module from the list of modules that are 760 * already linked into the kernel. 761 */ 762 static int 763 module_do_builtin(const module_t *pmod, const char *name, module_t **modp, 764 prop_dictionary_t props) 765 { 766 const char *p, *s; 767 char buf[MAXMODNAME]; 768 modinfo_t *mi = NULL; 769 module_t *mod, *mod2, *mod_loaded, *prev_active; 770 size_t len; 771 int error; 772 773 KASSERT(kernconfig_is_held()); 774 775 /* 776 * Search the list to see if we have a module by this name. 777 */ 778 TAILQ_FOREACH(mod, &module_builtins, mod_chain) { 779 if (strcmp(mod->mod_info->mi_name, name) == 0) { 780 mi = mod->mod_info; 781 break; 782 } 783 } 784 785 /* 786 * Check to see if already loaded. This might happen if we 787 * were already loaded as a dependency. 788 */ 789 if ((mod_loaded = module_lookup(name)) != NULL) { 790 KASSERT(mod == NULL); 791 if (modp) 792 *modp = mod_loaded; 793 return 0; 794 } 795 796 /* Note! This is from TAILQ, not immediate above */ 797 if (mi == NULL) { 798 /* 799 * XXX: We'd like to panic here, but currently in some 800 * cases (such as nfsserver + nfs), the dependee can be 801 * succesfully linked without the dependencies. 802 */ 803 module_error("%s: can't find builtin dependency `%s'", 804 pmod->mod_info->mi_name, name); 805 return ENOENT; 806 } 807 808 /* 809 * Initialize pre-requisites. 810 */ 811 if (mi->mi_required != NULL) { 812 for (s = mi->mi_required; *s != '\0'; s = p) { 813 if (*s == ',') 814 s++; 815 p = s; 816 while (*p != '\0' && *p != ',') 817 p++; 818 len = min(p - s + 1, sizeof(buf)); 819 strlcpy(buf, s, len); 820 if (buf[0] == '\0') 821 break; 822 if (mod->mod_nrequired == MAXMODDEPS - 1) { 823 module_error("%s: too many required modules " 824 "%d >= %d", pmod->mod_info->mi_name, 825 mod->mod_nrequired, MAXMODDEPS - 1); 826 return EINVAL; 827 } 828 error = module_do_builtin(mod, buf, &mod2, NULL); 829 if (error != 0) { 830 return error; 831 } 832 mod->mod_required[mod->mod_nrequired++] = mod2; 833 } 834 } 835 836 /* 837 * Try to initialize the module. 838 */ 839 prev_active = module_active; 840 module_active = mod; 841 error = (*mi->mi_modcmd)(MODULE_CMD_INIT, props); 842 module_active = prev_active; 843 if (error != 0) { 844 module_error("builtin module `%s' " 845 "failed to init, error %d", mi->mi_name, error); 846 return error; 847 } 848 849 /* load always succeeds after this point */ 850 851 TAILQ_REMOVE(&module_builtins, mod, mod_chain); 852 module_builtinlist--; 853 if (modp != NULL) { 854 *modp = mod; 855 } 856 module_enqueue(mod); 857 return 0; 858 } 859 860 /* 861 * module_do_load: 862 * 863 * Helper routine: load a module from the file system, or one 864 * pushed by the boot loader. 865 */ 866 static int 867 module_do_load(const char *name, bool isdep, int flags, 868 prop_dictionary_t props, module_t **modp, modclass_t modclass, 869 bool autoload) 870 { 871 #define MODULE_MAX_DEPTH 6 872 873 TAILQ_HEAD(pending_t, module); 874 static int depth = 0; 875 static struct pending_t *pending_lists[MODULE_MAX_DEPTH]; 876 struct pending_t *pending; 877 struct pending_t new_pending = TAILQ_HEAD_INITIALIZER(new_pending); 878 modinfo_t *mi; 879 module_t *mod, *mod2, *prev_active; 880 prop_dictionary_t filedict; 881 char buf[MAXMODNAME]; 882 const char *s, *p; 883 int error; 884 size_t len; 885 886 KASSERT(kernconfig_is_held()); 887 888 filedict = NULL; 889 error = 0; 890 891 /* 892 * Avoid recursing too far. 893 */ 894 if (++depth > MODULE_MAX_DEPTH) { 895 module_error("recursion too deep for `%s' %d > %d", name, 896 depth, MODULE_MAX_DEPTH); 897 depth--; 898 return EMLINK; 899 } 900 901 /* 902 * Set up the pending list for this depth. If this is a 903 * recursive entry, then use same list as for outer call, 904 * else use the locally allocated list. In either case, 905 * remember which one we're using. 906 */ 907 if (isdep) { 908 KASSERT(depth > 1); 909 pending = pending_lists[depth - 2]; 910 } else 911 pending = &new_pending; 912 pending_lists[depth - 1] = pending; 913 914 /* 915 * Search the list of disabled builtins first. 916 */ 917 TAILQ_FOREACH(mod, &module_builtins, mod_chain) { 918 if (strcmp(mod->mod_info->mi_name, name) == 0) { 919 break; 920 } 921 } 922 if (mod) { 923 if ((mod->mod_flags & MODFLG_MUST_FORCE) && 924 (flags & MODCTL_LOAD_FORCE) == 0) { 925 if (!autoload) { 926 module_error("use -f to reinstate " 927 "builtin module `%s'", name); 928 } 929 depth--; 930 return EPERM; 931 } else { 932 error = module_do_builtin(mod, name, modp, props); 933 depth--; 934 return error; 935 } 936 } 937 938 /* 939 * Load the module and link. Before going to the file system, 940 * scan the list of modules loaded by the boot loader. 941 */ 942 TAILQ_FOREACH(mod, &module_bootlist, mod_chain) { 943 if (strcmp(mod->mod_info->mi_name, name) == 0) { 944 TAILQ_REMOVE(&module_bootlist, mod, mod_chain); 945 break; 946 } 947 } 948 if (mod != NULL) { 949 TAILQ_INSERT_TAIL(pending, mod, mod_chain); 950 } else { 951 /* 952 * Check to see if module is already present. 953 */ 954 mod = module_lookup(name); 955 if (mod != NULL) { 956 if (modp != NULL) { 957 *modp = mod; 958 } 959 module_print("%s module `%s' already loaded", 960 isdep ? "dependent" : "requested", name); 961 depth--; 962 return EEXIST; 963 } 964 965 mod = module_newmodule(MODULE_SOURCE_FILESYS); 966 if (mod == NULL) { 967 module_error("out of memory for `%s'", name); 968 depth--; 969 return ENOMEM; 970 } 971 972 error = module_load_vfs_vec(name, flags, autoload, mod, 973 &filedict); 974 if (error != 0) { 975 #ifdef DEBUG 976 /* 977 * The exec class of modules contains a list of 978 * modules that is the union of all the modules 979 * available for each architecture, so we don't 980 * print an error if they are missing. 981 */ 982 if ((modclass != MODULE_CLASS_EXEC || error != ENOENT) 983 && root_device != NULL) 984 module_error("vfs load failed for `%s', " 985 "error %d", name, error); 986 #endif 987 kmem_free(mod, sizeof(*mod)); 988 depth--; 989 return error; 990 } 991 TAILQ_INSERT_TAIL(pending, mod, mod_chain); 992 993 error = module_fetch_info(mod); 994 if (error != 0) { 995 module_error("cannot fetch info for `%s', error %d", 996 name, error); 997 goto fail; 998 } 999 } 1000 1001 /* 1002 * Check compatibility. 1003 */ 1004 mi = mod->mod_info; 1005 if (strlen(mi->mi_name) >= MAXMODNAME) { 1006 error = EINVAL; 1007 module_error("module name `%s' longer than %d", mi->mi_name, 1008 MAXMODNAME); 1009 goto fail; 1010 } 1011 if (!module_compatible(mi->mi_version, __NetBSD_Version__)) { 1012 module_error("module `%s' built for `%d', system `%d'", 1013 mi->mi_name, mi->mi_version, __NetBSD_Version__); 1014 if ((flags & MODCTL_LOAD_FORCE) != 0) { 1015 module_error("forced load, system may be unstable"); 1016 } else { 1017 error = EPROGMISMATCH; 1018 goto fail; 1019 } 1020 } 1021 1022 /* 1023 * If a specific kind of module was requested, ensure that we have 1024 * a match. 1025 */ 1026 if (!MODULE_CLASS_MATCH(mi, modclass)) { 1027 module_incompat(mi, modclass); 1028 error = ENOENT; 1029 goto fail; 1030 } 1031 1032 /* 1033 * If loading a dependency, `name' is a plain module name. 1034 * The name must match. 1035 */ 1036 if (isdep && strcmp(mi->mi_name, name) != 0) { 1037 module_error("dependency name mismatch (`%s' != `%s')", 1038 name, mi->mi_name); 1039 error = ENOENT; 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 && error != EEXIST) { 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 module_print("module `%s' loaded successfully", mi->mi_name); 1157 return 0; 1158 1159 fail: 1160 kobj_unload(mod->mod_kobj); 1161 fail2: 1162 if (filedict != NULL) { 1163 prop_object_release(filedict); 1164 filedict = NULL; 1165 } 1166 TAILQ_REMOVE(pending, mod, mod_chain); 1167 kmem_free(mod, sizeof(*mod)); 1168 depth--; 1169 return error; 1170 } 1171 1172 /* 1173 * module_do_unload: 1174 * 1175 * Helper routine: do the dirty work of unloading a module. 1176 */ 1177 static int 1178 module_do_unload(const char *name, bool load_requires_force) 1179 { 1180 module_t *mod, *prev_active; 1181 int error; 1182 u_int i; 1183 1184 KASSERT(kernconfig_is_held()); 1185 KASSERT(name != NULL); 1186 1187 module_print("unload requested for '%s' (%s)", name, 1188 load_requires_force ? "TRUE" : "FALSE"); 1189 mod = module_lookup(name); 1190 if (mod == NULL) { 1191 module_error("module `%s' not found", name); 1192 return ENOENT; 1193 } 1194 if (mod->mod_refcnt != 0) { 1195 module_print("module `%s' busy (%d refs)", name, 1196 mod->mod_refcnt); 1197 return EBUSY; 1198 } 1199 1200 /* 1201 * Builtin secmodels are there to stay. 1202 */ 1203 if (mod->mod_source == MODULE_SOURCE_KERNEL && 1204 mod->mod_info->mi_class == MODULE_CLASS_SECMODEL) { 1205 module_print("cannot unload built-in secmodel module `%s'", 1206 name); 1207 return EPERM; 1208 } 1209 1210 prev_active = module_active; 1211 module_active = mod; 1212 error = (*mod->mod_info->mi_modcmd)(MODULE_CMD_FINI, NULL); 1213 module_active = prev_active; 1214 if (error != 0) { 1215 module_print("cannot unload module `%s' error=%d", name, 1216 error); 1217 return error; 1218 } 1219 module_count--; 1220 TAILQ_REMOVE(&module_list, mod, mod_chain); 1221 for (i = 0; i < mod->mod_nrequired; i++) { 1222 mod->mod_required[i]->mod_refcnt--; 1223 } 1224 module_print("unloaded module `%s'", name); 1225 if (mod->mod_kobj != NULL) { 1226 kobj_unload(mod->mod_kobj); 1227 } 1228 if (mod->mod_source == MODULE_SOURCE_KERNEL) { 1229 mod->mod_nrequired = 0; /* will be re-parsed */ 1230 if (load_requires_force) 1231 module_require_force(mod); 1232 TAILQ_INSERT_TAIL(&module_builtins, mod, mod_chain); 1233 module_builtinlist++; 1234 } else { 1235 kmem_free(mod, sizeof(*mod)); 1236 } 1237 module_gen++; 1238 1239 return 0; 1240 } 1241 1242 /* 1243 * module_prime: 1244 * 1245 * Push a module loaded by the bootloader onto our internal 1246 * list. 1247 */ 1248 int 1249 module_prime(const char *name, void *base, size_t size) 1250 { 1251 __link_set_decl(modules, modinfo_t); 1252 modinfo_t *const *mip; 1253 module_t *mod; 1254 int error; 1255 1256 /* Check for module name same as a built-in module */ 1257 1258 __link_set_foreach(mip, modules) { 1259 if (*mip == &module_dummy) 1260 continue; 1261 if (strcmp((*mip)->mi_name, name) == 0) { 1262 module_error("module `%s' pushed by boot loader " 1263 "already exists", name); 1264 return EEXIST; 1265 } 1266 } 1267 1268 /* Also eliminate duplicate boolist entries */ 1269 1270 TAILQ_FOREACH(mod, &module_bootlist, mod_chain) { 1271 if (strcmp(mod->mod_info->mi_name, name) == 0) { 1272 module_error("duplicate bootlist entry for module " 1273 "`%s'", name); 1274 return EEXIST; 1275 } 1276 } 1277 1278 mod = module_newmodule(MODULE_SOURCE_BOOT); 1279 if (mod == NULL) { 1280 return ENOMEM; 1281 } 1282 1283 error = kobj_load_mem(&mod->mod_kobj, name, base, size); 1284 if (error != 0) { 1285 kmem_free(mod, sizeof(*mod)); 1286 module_error("unable to load `%s' pushed by boot loader, " 1287 "error %d", name, error); 1288 return error; 1289 } 1290 error = module_fetch_info(mod); 1291 if (error != 0) { 1292 kobj_unload(mod->mod_kobj); 1293 kmem_free(mod, sizeof(*mod)); 1294 module_error("unable to fetch_info for `%s' pushed by boot " 1295 "loader, error %d", name, error); 1296 return error; 1297 } 1298 1299 TAILQ_INSERT_TAIL(&module_bootlist, mod, mod_chain); 1300 1301 return 0; 1302 } 1303 1304 /* 1305 * module_fetch_into: 1306 * 1307 * Fetch modinfo record from a loaded module. 1308 */ 1309 static int 1310 module_fetch_info(module_t *mod) 1311 { 1312 int error; 1313 void *addr; 1314 size_t size; 1315 1316 /* 1317 * Find module info record and check compatibility. 1318 */ 1319 error = kobj_find_section(mod->mod_kobj, "link_set_modules", 1320 &addr, &size); 1321 if (error != 0) { 1322 module_error("`link_set_modules' section not present, " 1323 "error %d", error); 1324 return error; 1325 } 1326 if (size != sizeof(modinfo_t **)) { 1327 module_error("`link_set_modules' section wrong size %zu != %zu", 1328 size, sizeof(modinfo_t **)); 1329 return ENOEXEC; 1330 } 1331 mod->mod_info = *(modinfo_t **)addr; 1332 1333 return 0; 1334 } 1335 1336 /* 1337 * module_find_section: 1338 * 1339 * Allows a module that is being initialized to look up a section 1340 * within its ELF object. 1341 */ 1342 int 1343 module_find_section(const char *name, void **addr, size_t *size) 1344 { 1345 1346 KASSERT(kernconfig_is_held()); 1347 KASSERT(module_active != NULL); 1348 1349 return kobj_find_section(module_active->mod_kobj, name, addr, size); 1350 } 1351 1352 /* 1353 * module_thread: 1354 * 1355 * Automatically unload modules. We try once to unload autoloaded 1356 * modules after module_autotime seconds. If the system is under 1357 * severe memory pressure, we'll try unloading all modules, else if 1358 * module_autotime is zero, we don't try to unload, even if the 1359 * module was previously scheduled for unload. 1360 */ 1361 static void 1362 module_thread(void *cookie) 1363 { 1364 module_t *mod, *next; 1365 modinfo_t *mi; 1366 int error; 1367 1368 for (;;) { 1369 kernconfig_lock(); 1370 for (mod = TAILQ_FIRST(&module_list); mod != NULL; mod = next) { 1371 next = TAILQ_NEXT(mod, mod_chain); 1372 1373 /* skip built-in modules */ 1374 if (mod->mod_source == MODULE_SOURCE_KERNEL) 1375 continue; 1376 /* skip modules that weren't auto-loaded */ 1377 if ((mod->mod_flags & MODFLG_AUTO_LOADED) == 0) 1378 continue; 1379 1380 if (uvmexp.free < uvmexp.freemin) { 1381 module_thread_ticks = hz; 1382 } else if (module_autotime == 0 || 1383 mod->mod_autotime == 0) { 1384 continue; 1385 } else if (time_second < mod->mod_autotime) { 1386 module_thread_ticks = hz; 1387 continue; 1388 } else { 1389 mod->mod_autotime = 0; 1390 } 1391 1392 /* 1393 * If this module wants to avoid autounload then 1394 * skip it. Some modules can ping-pong in and out 1395 * because their use is transient but often. 1396 * Example: exec_script. 1397 */ 1398 mi = mod->mod_info; 1399 error = (*mi->mi_modcmd)(MODULE_CMD_AUTOUNLOAD, NULL); 1400 if (error == 0 || error == ENOTTY) { 1401 (void)module_do_unload(mi->mi_name, false); 1402 } else 1403 module_print("module `%s' declined to be " 1404 "auto-unloaded error=%d", mi->mi_name, 1405 error); 1406 } 1407 kernconfig_unlock(); 1408 1409 mutex_enter(&module_thread_lock); 1410 (void)cv_timedwait(&module_thread_cv, &module_thread_lock, 1411 module_thread_ticks); 1412 module_thread_ticks = 0; 1413 mutex_exit(&module_thread_lock); 1414 } 1415 } 1416 1417 /* 1418 * module_thread: 1419 * 1420 * Kick the module thread into action, perhaps because the 1421 * system is low on memory. 1422 */ 1423 void 1424 module_thread_kick(void) 1425 { 1426 1427 mutex_enter(&module_thread_lock); 1428 module_thread_ticks = hz; 1429 cv_broadcast(&module_thread_cv); 1430 mutex_exit(&module_thread_lock); 1431 } 1432 1433 #ifdef DDB 1434 /* 1435 * module_whatis: 1436 * 1437 * Helper routine for DDB. 1438 */ 1439 void 1440 module_whatis(uintptr_t addr, void (*pr)(const char *, ...)) 1441 { 1442 module_t *mod; 1443 size_t msize; 1444 vaddr_t maddr; 1445 1446 TAILQ_FOREACH(mod, &module_list, mod_chain) { 1447 if (mod->mod_kobj == NULL) { 1448 continue; 1449 } 1450 if (kobj_stat(mod->mod_kobj, &maddr, &msize) != 0) 1451 continue; 1452 if (addr < maddr || addr >= maddr + msize) { 1453 continue; 1454 } 1455 (*pr)("%p is %p+%zu, in kernel module `%s'\n", 1456 (void *)addr, (void *)maddr, 1457 (size_t)(addr - maddr), mod->mod_info->mi_name); 1458 } 1459 } 1460 1461 /* 1462 * module_print_list: 1463 * 1464 * Helper routine for DDB. 1465 */ 1466 void 1467 module_print_list(void (*pr)(const char *, ...)) 1468 { 1469 const char *src; 1470 module_t *mod; 1471 size_t msize; 1472 vaddr_t maddr; 1473 1474 (*pr)("%16s %16s %8s %8s\n", "NAME", "TEXT/DATA", "SIZE", "SOURCE"); 1475 1476 TAILQ_FOREACH(mod, &module_list, mod_chain) { 1477 switch (mod->mod_source) { 1478 case MODULE_SOURCE_KERNEL: 1479 src = "builtin"; 1480 break; 1481 case MODULE_SOURCE_FILESYS: 1482 src = "filesys"; 1483 break; 1484 case MODULE_SOURCE_BOOT: 1485 src = "boot"; 1486 break; 1487 default: 1488 src = "unknown"; 1489 break; 1490 } 1491 if (mod->mod_kobj == NULL) { 1492 maddr = 0; 1493 msize = 0; 1494 } else if (kobj_stat(mod->mod_kobj, &maddr, &msize) != 0) 1495 continue; 1496 (*pr)("%16s %16lx %8ld %8s\n", mod->mod_info->mi_name, 1497 (long)maddr, (long)msize, src); 1498 } 1499 } 1500 #endif /* DDB */ 1501 1502 static bool 1503 module_merge_dicts(prop_dictionary_t existing_dict, 1504 const prop_dictionary_t new_dict) 1505 { 1506 prop_dictionary_keysym_t props_keysym; 1507 prop_object_iterator_t props_iter; 1508 prop_object_t props_obj; 1509 const char *props_key; 1510 bool error; 1511 1512 if (new_dict == NULL) { /* nothing to merge */ 1513 return true; 1514 } 1515 1516 error = false; 1517 props_iter = prop_dictionary_iterator(new_dict); 1518 if (props_iter == NULL) { 1519 return false; 1520 } 1521 1522 while ((props_obj = prop_object_iterator_next(props_iter)) != NULL) { 1523 props_keysym = (prop_dictionary_keysym_t)props_obj; 1524 props_key = prop_dictionary_keysym_cstring_nocopy(props_keysym); 1525 props_obj = prop_dictionary_get_keysym(new_dict, props_keysym); 1526 if ((props_obj == NULL) || !prop_dictionary_set(existing_dict, 1527 props_key, props_obj)) { 1528 error = true; 1529 goto out; 1530 } 1531 } 1532 error = false; 1533 1534 out: 1535 prop_object_iterator_release(props_iter); 1536 1537 return !error; 1538 } 1539