1 /* $NetBSD: kern_module.c,v 1.119 2016/12/27 09:34:44 maya 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 1.119 2016/12/27 09:34:44 maya 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 int error; 574 575 /* Authorize. */ 576 error = kauth_authorize_system(kauth_cred_get(), KAUTH_SYSTEM_MODULE, 577 0, (void *)(uintptr_t)MODCTL_LOAD, NULL, NULL); 578 if (error != 0) { 579 return error; 580 } 581 582 kernconfig_lock(); 583 error = module_do_load(filename, false, flags, props, NULL, modclass, 584 false); 585 kernconfig_unlock(); 586 587 return error; 588 } 589 590 /* 591 * module_autoload: 592 * 593 * Load a single module from the file system, system initiated. 594 */ 595 int 596 module_autoload(const char *filename, modclass_t modclass) 597 { 598 int error; 599 600 kernconfig_lock(); 601 602 /* Nothing if the user has disabled it. */ 603 if (!module_autoload_on) { 604 kernconfig_unlock(); 605 return EPERM; 606 } 607 608 /* Disallow path separators and magic symlinks. */ 609 if (strchr(filename, '/') != NULL || strchr(filename, '@') != NULL || 610 strchr(filename, '.') != NULL) { 611 kernconfig_unlock(); 612 return EPERM; 613 } 614 615 /* Authorize. */ 616 error = kauth_authorize_system(kauth_cred_get(), KAUTH_SYSTEM_MODULE, 617 0, (void *)(uintptr_t)MODCTL_LOAD, (void *)(uintptr_t)1, NULL); 618 619 if (error == 0) 620 error = module_do_load(filename, false, 0, NULL, NULL, modclass, 621 true); 622 623 kernconfig_unlock(); 624 return error; 625 } 626 627 /* 628 * module_unload: 629 * 630 * Find and unload a module by name. 631 */ 632 int 633 module_unload(const char *name) 634 { 635 int error; 636 637 /* Authorize. */ 638 error = kauth_authorize_system(kauth_cred_get(), KAUTH_SYSTEM_MODULE, 639 0, (void *)(uintptr_t)MODCTL_UNLOAD, NULL, NULL); 640 if (error != 0) { 641 return error; 642 } 643 644 kernconfig_lock(); 645 error = module_do_unload(name, true); 646 kernconfig_unlock(); 647 648 return error; 649 } 650 651 /* 652 * module_lookup: 653 * 654 * Look up a module by name. 655 */ 656 module_t * 657 module_lookup(const char *name) 658 { 659 module_t *mod; 660 661 KASSERT(kernconfig_is_held()); 662 663 TAILQ_FOREACH(mod, &module_list, mod_chain) { 664 if (strcmp(mod->mod_info->mi_name, name) == 0) { 665 break; 666 } 667 } 668 669 return mod; 670 } 671 672 /* 673 * module_hold: 674 * 675 * Add a single reference to a module. It's the caller's 676 * responsibility to ensure that the reference is dropped 677 * later. 678 */ 679 int 680 module_hold(const char *name) 681 { 682 module_t *mod; 683 684 kernconfig_lock(); 685 mod = module_lookup(name); 686 if (mod == NULL) { 687 kernconfig_unlock(); 688 return ENOENT; 689 } 690 mod->mod_refcnt++; 691 kernconfig_unlock(); 692 693 return 0; 694 } 695 696 /* 697 * module_rele: 698 * 699 * Release a reference acquired with module_hold(). 700 */ 701 void 702 module_rele(const char *name) 703 { 704 module_t *mod; 705 706 kernconfig_lock(); 707 mod = module_lookup(name); 708 if (mod == NULL) { 709 kernconfig_unlock(); 710 panic("%s: gone", __func__); 711 } 712 mod->mod_refcnt--; 713 kernconfig_unlock(); 714 } 715 716 /* 717 * module_enqueue: 718 * 719 * Put a module onto the global list and update counters. 720 */ 721 void 722 module_enqueue(module_t *mod) 723 { 724 int i; 725 726 KASSERT(kernconfig_is_held()); 727 728 /* 729 * Put new entry at the head of the queue so autounload can unload 730 * requisite modules with only one pass through the queue. 731 */ 732 TAILQ_INSERT_HEAD(&module_list, mod, mod_chain); 733 if (mod->mod_nrequired) { 734 735 /* Add references to the requisite modules. */ 736 for (i = 0; i < mod->mod_nrequired; i++) { 737 KASSERT(mod->mod_required[i] != NULL); 738 mod->mod_required[i]->mod_refcnt++; 739 } 740 } 741 module_count++; 742 module_gen++; 743 } 744 745 /* 746 * module_do_builtin: 747 * 748 * Initialize a module from the list of modules that are 749 * already linked into the kernel. 750 */ 751 static int 752 module_do_builtin(const module_t *pmod, const char *name, module_t **modp, 753 prop_dictionary_t props) 754 { 755 const char *p, *s; 756 char buf[MAXMODNAME]; 757 modinfo_t *mi = NULL; 758 module_t *mod, *mod2, *mod_loaded, *prev_active; 759 size_t len; 760 int error; 761 762 KASSERT(kernconfig_is_held()); 763 764 /* 765 * Search the list to see if we have a module by this name. 766 */ 767 TAILQ_FOREACH(mod, &module_builtins, mod_chain) { 768 if (strcmp(mod->mod_info->mi_name, name) == 0) { 769 mi = mod->mod_info; 770 break; 771 } 772 } 773 774 /* 775 * Check to see if already loaded. This might happen if we 776 * were already loaded as a dependency. 777 */ 778 if ((mod_loaded = module_lookup(name)) != NULL) { 779 KASSERT(mod == NULL); 780 if (modp) 781 *modp = mod_loaded; 782 return 0; 783 } 784 785 /* Note! This is from TAILQ, not immediate above */ 786 if (mi == NULL) { 787 /* 788 * XXX: We'd like to panic here, but currently in some 789 * cases (such as nfsserver + nfs), the dependee can be 790 * succesfully linked without the dependencies. 791 */ 792 module_error("%s: can't find builtin dependency `%s'", 793 pmod->mod_info->mi_name, name); 794 return ENOENT; 795 } 796 797 /* 798 * Initialize pre-requisites. 799 */ 800 if (mi->mi_required != NULL) { 801 for (s = mi->mi_required; *s != '\0'; s = p) { 802 if (*s == ',') 803 s++; 804 p = s; 805 while (*p != '\0' && *p != ',') 806 p++; 807 len = min(p - s + 1, sizeof(buf)); 808 strlcpy(buf, s, len); 809 if (buf[0] == '\0') 810 break; 811 if (mod->mod_nrequired == MAXMODDEPS - 1) { 812 module_error("%s: too many required modules " 813 "%d >= %d", pmod->mod_info->mi_name, 814 mod->mod_nrequired, MAXMODDEPS - 1); 815 return EINVAL; 816 } 817 error = module_do_builtin(mod, buf, &mod2, NULL); 818 if (error != 0) { 819 return error; 820 } 821 mod->mod_required[mod->mod_nrequired++] = mod2; 822 } 823 } 824 825 /* 826 * Try to initialize the module. 827 */ 828 prev_active = module_active; 829 module_active = mod; 830 error = (*mi->mi_modcmd)(MODULE_CMD_INIT, props); 831 module_active = prev_active; 832 if (error != 0) { 833 module_error("builtin module `%s' " 834 "failed to init, error %d", mi->mi_name, error); 835 return error; 836 } 837 838 /* load always succeeds after this point */ 839 840 TAILQ_REMOVE(&module_builtins, mod, mod_chain); 841 module_builtinlist--; 842 if (modp != NULL) { 843 *modp = mod; 844 } 845 module_enqueue(mod); 846 return 0; 847 } 848 849 /* 850 * module_do_load: 851 * 852 * Helper routine: load a module from the file system, or one 853 * pushed by the boot loader. 854 */ 855 static int 856 module_do_load(const char *name, bool isdep, int flags, 857 prop_dictionary_t props, module_t **modp, modclass_t modclass, 858 bool autoload) 859 { 860 #define MODULE_MAX_DEPTH 6 861 862 TAILQ_HEAD(pending_t, module); 863 static int depth = 0; 864 static struct pending_t *pending_lists[MODULE_MAX_DEPTH]; 865 struct pending_t *pending; 866 struct pending_t new_pending = TAILQ_HEAD_INITIALIZER(new_pending); 867 modinfo_t *mi; 868 module_t *mod, *mod2, *prev_active; 869 prop_dictionary_t filedict; 870 char buf[MAXMODNAME]; 871 const char *s, *p; 872 int error; 873 size_t len; 874 875 KASSERT(kernconfig_is_held()); 876 877 filedict = NULL; 878 error = 0; 879 880 /* 881 * Avoid recursing too far. 882 */ 883 if (++depth > MODULE_MAX_DEPTH) { 884 module_error("recursion too deep for `%s' %d > %d", name, 885 depth, MODULE_MAX_DEPTH); 886 depth--; 887 return EMLINK; 888 } 889 890 /* 891 * Set up the pending list for this depth. If this is a 892 * recursive entry, then use same list as for outer call, 893 * else use the locally allocated list. In either case, 894 * remember which one we're using. 895 */ 896 if (isdep) { 897 KASSERT(depth > 1); 898 pending = pending_lists[depth - 2]; 899 } else 900 pending = &new_pending; 901 pending_lists[depth - 1] = pending; 902 903 /* 904 * Search the list of disabled builtins first. 905 */ 906 TAILQ_FOREACH(mod, &module_builtins, mod_chain) { 907 if (strcmp(mod->mod_info->mi_name, name) == 0) { 908 break; 909 } 910 } 911 if (mod) { 912 if ((mod->mod_flags & MODFLG_MUST_FORCE) && 913 (flags & MODCTL_LOAD_FORCE) == 0) { 914 if (!autoload) { 915 module_error("use -f to reinstate " 916 "builtin module `%s'", name); 917 } 918 depth--; 919 return EPERM; 920 } else { 921 error = module_do_builtin(mod, name, modp, props); 922 depth--; 923 return error; 924 } 925 } 926 927 /* 928 * Load the module and link. Before going to the file system, 929 * scan the list of modules loaded by the boot loader. 930 */ 931 TAILQ_FOREACH(mod, &module_bootlist, mod_chain) { 932 if (strcmp(mod->mod_info->mi_name, name) == 0) { 933 TAILQ_REMOVE(&module_bootlist, mod, mod_chain); 934 break; 935 } 936 } 937 if (mod != NULL) { 938 TAILQ_INSERT_TAIL(pending, mod, mod_chain); 939 } else { 940 /* 941 * Check to see if module is already present. 942 */ 943 mod = module_lookup(name); 944 if (mod != NULL) { 945 if (modp != NULL) { 946 *modp = mod; 947 } 948 module_print("%s module `%s' already loaded", 949 isdep ? "dependent" : "requested", name); 950 depth--; 951 return EEXIST; 952 } 953 954 mod = module_newmodule(MODULE_SOURCE_FILESYS); 955 if (mod == NULL) { 956 module_error("out of memory for `%s'", name); 957 depth--; 958 return ENOMEM; 959 } 960 961 error = module_load_vfs_vec(name, flags, autoload, mod, 962 &filedict); 963 if (error != 0) { 964 #ifdef DEBUG 965 /* 966 * The exec class of modules contains a list of 967 * modules that is the union of all the modules 968 * available for each architecture, so we don't 969 * print an error if they are missing. 970 */ 971 if ((modclass != MODULE_CLASS_EXEC || error != ENOENT) 972 && root_device != NULL) 973 module_error("vfs load failed for `%s', " 974 "error %d", name, error); 975 #endif 976 kmem_free(mod, sizeof(*mod)); 977 depth--; 978 return error; 979 } 980 TAILQ_INSERT_TAIL(pending, mod, mod_chain); 981 982 error = module_fetch_info(mod); 983 if (error != 0) { 984 module_error("cannot fetch info for `%s', error %d", 985 name, error); 986 goto fail; 987 } 988 } 989 990 /* 991 * Check compatibility. 992 */ 993 mi = mod->mod_info; 994 if (strlen(mi->mi_name) >= MAXMODNAME) { 995 error = EINVAL; 996 module_error("module name `%s' longer than %d", mi->mi_name, 997 MAXMODNAME); 998 goto fail; 999 } 1000 if (!module_compatible(mi->mi_version, __NetBSD_Version__)) { 1001 module_error("module `%s' built for `%d', system `%d'", 1002 mi->mi_name, mi->mi_version, __NetBSD_Version__); 1003 if ((flags & MODCTL_LOAD_FORCE) != 0) { 1004 module_error("forced load, system may be unstable"); 1005 } else { 1006 error = EPROGMISMATCH; 1007 goto fail; 1008 } 1009 } 1010 1011 /* 1012 * If a specific kind of module was requested, ensure that we have 1013 * a match. 1014 */ 1015 if (!MODULE_CLASS_MATCH(mi, modclass)) { 1016 module_incompat(mi, modclass); 1017 error = ENOENT; 1018 goto fail; 1019 } 1020 1021 /* 1022 * If loading a dependency, `name' is a plain module name. 1023 * The name must match. 1024 */ 1025 if (isdep && strcmp(mi->mi_name, name) != 0) { 1026 module_error("dependency name mismatch (`%s' != `%s')", 1027 name, mi->mi_name); 1028 error = ENOENT; 1029 goto fail; 1030 } 1031 1032 /* 1033 * Block circular dependencies. 1034 */ 1035 TAILQ_FOREACH(mod2, pending, mod_chain) { 1036 if (mod == mod2) { 1037 continue; 1038 } 1039 if (strcmp(mod2->mod_info->mi_name, mi->mi_name) == 0) { 1040 error = EDEADLK; 1041 module_error("circular dependency detected for `%s'", 1042 mi->mi_name); 1043 goto fail; 1044 } 1045 } 1046 1047 /* 1048 * Now try to load any requisite modules. 1049 */ 1050 if (mi->mi_required != NULL) { 1051 for (s = mi->mi_required; *s != '\0'; s = p) { 1052 if (*s == ',') 1053 s++; 1054 p = s; 1055 while (*p != '\0' && *p != ',') 1056 p++; 1057 len = p - s + 1; 1058 if (len >= MAXMODNAME) { 1059 error = EINVAL; 1060 module_error("required module name `%s' " 1061 "longer than %d", mi->mi_required, 1062 MAXMODNAME); 1063 goto fail; 1064 } 1065 strlcpy(buf, s, len); 1066 if (buf[0] == '\0') 1067 break; 1068 if (mod->mod_nrequired == MAXMODDEPS - 1) { 1069 error = EINVAL; 1070 module_error("too many required modules " 1071 "%d >= %d", mod->mod_nrequired, 1072 MAXMODDEPS - 1); 1073 goto fail; 1074 } 1075 if (strcmp(buf, mi->mi_name) == 0) { 1076 error = EDEADLK; 1077 module_error("self-dependency detected for " 1078 "`%s'", mi->mi_name); 1079 goto fail; 1080 } 1081 error = module_do_load(buf, true, flags, NULL, 1082 &mod2, MODULE_CLASS_ANY, true); 1083 if (error != 0 && error != EEXIST) { 1084 module_error("recursive load failed for `%s' " 1085 "(`%s' required), error %d", mi->mi_name, 1086 buf, error); 1087 goto fail; 1088 } 1089 mod->mod_required[mod->mod_nrequired++] = mod2; 1090 } 1091 } 1092 1093 /* 1094 * We loaded all needed modules successfully: perform global 1095 * relocations and initialize. 1096 */ 1097 error = kobj_affix(mod->mod_kobj, mi->mi_name); 1098 if (error != 0) { 1099 /* Cannot touch 'mi' as the module is now gone. */ 1100 module_error("unable to affix module `%s', error %d", name, 1101 error); 1102 goto fail2; 1103 } 1104 1105 if (filedict) { 1106 if (!module_merge_dicts(filedict, props)) { 1107 module_error("module properties failed for %s", name); 1108 error = EINVAL; 1109 goto fail; 1110 } 1111 } 1112 prev_active = module_active; 1113 module_active = mod; 1114 error = (*mi->mi_modcmd)(MODULE_CMD_INIT, filedict ? filedict : props); 1115 module_active = prev_active; 1116 if (filedict) { 1117 prop_object_release(filedict); 1118 filedict = NULL; 1119 } 1120 if (error != 0) { 1121 module_error("modcmd function failed for `%s', error %d", 1122 mi->mi_name, error); 1123 goto fail; 1124 } 1125 1126 /* 1127 * Good, the module loaded successfully. Put it onto the 1128 * list and add references to its requisite modules. 1129 */ 1130 TAILQ_REMOVE(pending, mod, mod_chain); 1131 module_enqueue(mod); 1132 if (modp != NULL) { 1133 *modp = mod; 1134 } 1135 if (autoload && module_autotime > 0) { 1136 /* 1137 * Arrange to try unloading the module after 1138 * a short delay unless auto-unload is disabled. 1139 */ 1140 mod->mod_autotime = time_second + module_autotime; 1141 mod->mod_flags |= MODFLG_AUTO_LOADED; 1142 module_thread_kick(); 1143 } 1144 depth--; 1145 module_print("module `%s' loaded successfully", mi->mi_name); 1146 return 0; 1147 1148 fail: 1149 kobj_unload(mod->mod_kobj); 1150 fail2: 1151 if (filedict != NULL) { 1152 prop_object_release(filedict); 1153 filedict = NULL; 1154 } 1155 TAILQ_REMOVE(pending, mod, mod_chain); 1156 kmem_free(mod, sizeof(*mod)); 1157 depth--; 1158 return error; 1159 } 1160 1161 /* 1162 * module_do_unload: 1163 * 1164 * Helper routine: do the dirty work of unloading a module. 1165 */ 1166 static int 1167 module_do_unload(const char *name, bool load_requires_force) 1168 { 1169 module_t *mod, *prev_active; 1170 int error; 1171 u_int i; 1172 1173 KASSERT(kernconfig_is_held()); 1174 KASSERT(name != NULL); 1175 1176 module_print("unload requested for '%s' (%s)", name, 1177 load_requires_force ? "TRUE" : "FALSE"); 1178 mod = module_lookup(name); 1179 if (mod == NULL) { 1180 module_error("module `%s' not found", name); 1181 return ENOENT; 1182 } 1183 if (mod->mod_refcnt != 0) { 1184 module_print("module `%s' busy (%d refs)", name, 1185 mod->mod_refcnt); 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 module_print("cannot unload built-in secmodel module `%s'", 1195 name); 1196 return EPERM; 1197 } 1198 1199 prev_active = module_active; 1200 module_active = mod; 1201 error = (*mod->mod_info->mi_modcmd)(MODULE_CMD_FINI, NULL); 1202 module_active = prev_active; 1203 if (error != 0) { 1204 module_print("cannot unload module `%s' error=%d", name, 1205 error); 1206 return error; 1207 } 1208 module_count--; 1209 TAILQ_REMOVE(&module_list, mod, mod_chain); 1210 for (i = 0; i < mod->mod_nrequired; i++) { 1211 mod->mod_required[i]->mod_refcnt--; 1212 } 1213 module_print("unloaded module `%s'", name); 1214 if (mod->mod_kobj != NULL) { 1215 kobj_unload(mod->mod_kobj); 1216 } 1217 if (mod->mod_source == MODULE_SOURCE_KERNEL) { 1218 mod->mod_nrequired = 0; /* will be re-parsed */ 1219 if (load_requires_force) 1220 module_require_force(mod); 1221 TAILQ_INSERT_TAIL(&module_builtins, mod, mod_chain); 1222 module_builtinlist++; 1223 } else { 1224 kmem_free(mod, sizeof(*mod)); 1225 } 1226 module_gen++; 1227 1228 return 0; 1229 } 1230 1231 /* 1232 * module_prime: 1233 * 1234 * Push a module loaded by the bootloader onto our internal 1235 * list. 1236 */ 1237 int 1238 module_prime(const char *name, void *base, size_t size) 1239 { 1240 __link_set_decl(modules, modinfo_t); 1241 modinfo_t *const *mip; 1242 module_t *mod; 1243 int error; 1244 1245 /* Check for module name same as a built-in module */ 1246 1247 __link_set_foreach(mip, modules) { 1248 if (*mip == &module_dummy) 1249 continue; 1250 if (strcmp((*mip)->mi_name, name) == 0) { 1251 module_error("module `%s' pushed by boot loader " 1252 "already exists", name); 1253 return EEXIST; 1254 } 1255 } 1256 1257 /* Also eliminate duplicate boolist entries */ 1258 1259 TAILQ_FOREACH(mod, &module_bootlist, mod_chain) { 1260 if (strcmp(mod->mod_info->mi_name, name) == 0) { 1261 module_error("duplicate bootlist entry for module " 1262 "`%s'", name); 1263 return EEXIST; 1264 } 1265 } 1266 1267 mod = module_newmodule(MODULE_SOURCE_BOOT); 1268 if (mod == NULL) { 1269 return ENOMEM; 1270 } 1271 1272 error = kobj_load_mem(&mod->mod_kobj, name, base, size); 1273 if (error != 0) { 1274 kmem_free(mod, sizeof(*mod)); 1275 module_error("unable to load `%s' pushed by boot loader, " 1276 "error %d", name, error); 1277 return error; 1278 } 1279 error = module_fetch_info(mod); 1280 if (error != 0) { 1281 kobj_unload(mod->mod_kobj); 1282 kmem_free(mod, sizeof(*mod)); 1283 module_error("unable to fetch_info for `%s' pushed by boot " 1284 "loader, error %d", name, error); 1285 return error; 1286 } 1287 1288 TAILQ_INSERT_TAIL(&module_bootlist, mod, mod_chain); 1289 1290 return 0; 1291 } 1292 1293 /* 1294 * module_fetch_into: 1295 * 1296 * Fetch modinfo record from a loaded module. 1297 */ 1298 static int 1299 module_fetch_info(module_t *mod) 1300 { 1301 int error; 1302 void *addr; 1303 size_t size; 1304 1305 /* 1306 * Find module info record and check compatibility. 1307 */ 1308 error = kobj_find_section(mod->mod_kobj, "link_set_modules", 1309 &addr, &size); 1310 if (error != 0) { 1311 module_error("`link_set_modules' section not present, " 1312 "error %d", error); 1313 return error; 1314 } 1315 if (size != sizeof(modinfo_t **)) { 1316 module_error("`link_set_modules' section wrong size %zu != %zu", 1317 size, sizeof(modinfo_t **)); 1318 return ENOEXEC; 1319 } 1320 mod->mod_info = *(modinfo_t **)addr; 1321 1322 return 0; 1323 } 1324 1325 /* 1326 * module_find_section: 1327 * 1328 * Allows a module that is being initialized to look up a section 1329 * within its ELF object. 1330 */ 1331 int 1332 module_find_section(const char *name, void **addr, size_t *size) 1333 { 1334 1335 KASSERT(kernconfig_is_held()); 1336 KASSERT(module_active != NULL); 1337 1338 return kobj_find_section(module_active->mod_kobj, name, addr, size); 1339 } 1340 1341 /* 1342 * module_thread: 1343 * 1344 * Automatically unload modules. We try once to unload autoloaded 1345 * modules after module_autotime seconds. If the system is under 1346 * severe memory pressure, we'll try unloading all modules, else if 1347 * module_autotime is zero, we don't try to unload, even if the 1348 * module was previously scheduled for unload. 1349 */ 1350 static void 1351 module_thread(void *cookie) 1352 { 1353 module_t *mod, *next; 1354 modinfo_t *mi; 1355 int error; 1356 1357 for (;;) { 1358 kernconfig_lock(); 1359 for (mod = TAILQ_FIRST(&module_list); mod != NULL; mod = next) { 1360 next = TAILQ_NEXT(mod, mod_chain); 1361 1362 /* skip built-in modules */ 1363 if (mod->mod_source == MODULE_SOURCE_KERNEL) 1364 continue; 1365 /* skip modules that weren't auto-loaded */ 1366 if ((mod->mod_flags & MODFLG_AUTO_LOADED) == 0) 1367 continue; 1368 1369 if (uvmexp.free < uvmexp.freemin) { 1370 module_thread_ticks = hz; 1371 } else if (module_autotime == 0 || 1372 mod->mod_autotime == 0) { 1373 continue; 1374 } else if (time_second < mod->mod_autotime) { 1375 module_thread_ticks = hz; 1376 continue; 1377 } else { 1378 mod->mod_autotime = 0; 1379 } 1380 1381 /* 1382 * If this module wants to avoid autounload then 1383 * skip it. Some modules can ping-pong in and out 1384 * because their use is transient but often. 1385 * Example: exec_script. 1386 */ 1387 mi = mod->mod_info; 1388 error = (*mi->mi_modcmd)(MODULE_CMD_AUTOUNLOAD, NULL); 1389 if (error == 0 || error == ENOTTY) { 1390 (void)module_do_unload(mi->mi_name, false); 1391 } else 1392 module_print("module `%s' declined to be " 1393 "auto-unloaded error=%d", mi->mi_name, 1394 error); 1395 } 1396 kernconfig_unlock(); 1397 1398 mutex_enter(&module_thread_lock); 1399 (void)cv_timedwait(&module_thread_cv, &module_thread_lock, 1400 module_thread_ticks); 1401 module_thread_ticks = 0; 1402 mutex_exit(&module_thread_lock); 1403 } 1404 } 1405 1406 /* 1407 * module_thread: 1408 * 1409 * Kick the module thread into action, perhaps because the 1410 * system is low on memory. 1411 */ 1412 void 1413 module_thread_kick(void) 1414 { 1415 1416 mutex_enter(&module_thread_lock); 1417 module_thread_ticks = hz; 1418 cv_broadcast(&module_thread_cv); 1419 mutex_exit(&module_thread_lock); 1420 } 1421 1422 #ifdef DDB 1423 /* 1424 * module_whatis: 1425 * 1426 * Helper routine for DDB. 1427 */ 1428 void 1429 module_whatis(uintptr_t addr, void (*pr)(const char *, ...)) 1430 { 1431 module_t *mod; 1432 size_t msize; 1433 vaddr_t maddr; 1434 1435 TAILQ_FOREACH(mod, &module_list, mod_chain) { 1436 if (mod->mod_kobj == NULL) { 1437 continue; 1438 } 1439 if (kobj_stat(mod->mod_kobj, &maddr, &msize) != 0) 1440 continue; 1441 if (addr < maddr || addr >= maddr + msize) { 1442 continue; 1443 } 1444 (*pr)("%p is %p+%zu, in kernel module `%s'\n", 1445 (void *)addr, (void *)maddr, 1446 (size_t)(addr - maddr), mod->mod_info->mi_name); 1447 } 1448 } 1449 1450 /* 1451 * module_print_list: 1452 * 1453 * Helper routine for DDB. 1454 */ 1455 void 1456 module_print_list(void (*pr)(const char *, ...)) 1457 { 1458 const char *src; 1459 module_t *mod; 1460 size_t msize; 1461 vaddr_t maddr; 1462 1463 (*pr)("%16s %16s %8s %8s\n", "NAME", "TEXT/DATA", "SIZE", "SOURCE"); 1464 1465 TAILQ_FOREACH(mod, &module_list, mod_chain) { 1466 switch (mod->mod_source) { 1467 case MODULE_SOURCE_KERNEL: 1468 src = "builtin"; 1469 break; 1470 case MODULE_SOURCE_FILESYS: 1471 src = "filesys"; 1472 break; 1473 case MODULE_SOURCE_BOOT: 1474 src = "boot"; 1475 break; 1476 default: 1477 src = "unknown"; 1478 break; 1479 } 1480 if (mod->mod_kobj == NULL) { 1481 maddr = 0; 1482 msize = 0; 1483 } else if (kobj_stat(mod->mod_kobj, &maddr, &msize) != 0) 1484 continue; 1485 (*pr)("%16s %16lx %8ld %8s\n", mod->mod_info->mi_name, 1486 (long)maddr, (long)msize, src); 1487 } 1488 } 1489 #endif /* DDB */ 1490 1491 static bool 1492 module_merge_dicts(prop_dictionary_t existing_dict, 1493 const prop_dictionary_t new_dict) 1494 { 1495 prop_dictionary_keysym_t props_keysym; 1496 prop_object_iterator_t props_iter; 1497 prop_object_t props_obj; 1498 const char *props_key; 1499 bool error; 1500 1501 if (new_dict == NULL) { /* nothing to merge */ 1502 return true; 1503 } 1504 1505 error = false; 1506 props_iter = prop_dictionary_iterator(new_dict); 1507 if (props_iter == NULL) { 1508 return false; 1509 } 1510 1511 while ((props_obj = prop_object_iterator_next(props_iter)) != NULL) { 1512 props_keysym = (prop_dictionary_keysym_t)props_obj; 1513 props_key = prop_dictionary_keysym_cstring_nocopy(props_keysym); 1514 props_obj = prop_dictionary_get_keysym(new_dict, props_keysym); 1515 if ((props_obj == NULL) || !prop_dictionary_set(existing_dict, 1516 props_key, props_obj)) { 1517 error = true; 1518 goto out; 1519 } 1520 } 1521 error = false; 1522 1523 out: 1524 prop_object_iterator_release(props_iter); 1525 1526 return !error; 1527 } 1528