1 /* $NetBSD: kern_module.c,v 1.153 2021/09/16 21:29:42 andvar 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 1.153 2021/09/16 21:29:42 andvar 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/lwp.h> 51 #include <sys/kauth.h> 52 #include <sys/kobj.h> 53 #include <sys/kmem.h> 54 #include <sys/module.h> 55 #include <sys/module_hook.h> 56 #include <sys/kthread.h> 57 #include <sys/sysctl.h> 58 #include <sys/lock.h> 59 #include <sys/evcnt.h> 60 61 #include <uvm/uvm_extern.h> 62 63 struct vm_map *module_map; 64 const char *module_machine; 65 char module_base[MODULE_BASE_SIZE]; 66 67 struct modlist module_list = TAILQ_HEAD_INITIALIZER(module_list); 68 struct modlist module_builtins = TAILQ_HEAD_INITIALIZER(module_builtins); 69 static struct modlist module_bootlist = TAILQ_HEAD_INITIALIZER(module_bootlist); 70 71 struct module_callbacks { 72 TAILQ_ENTRY(module_callbacks) modcb_list; 73 void (*modcb_load)(struct module *); 74 void (*modcb_unload)(struct module *); 75 }; 76 TAILQ_HEAD(modcblist, module_callbacks); 77 static struct modcblist modcblist; 78 79 static module_t *module_netbsd; 80 static const modinfo_t module_netbsd_modinfo = { 81 .mi_version = __NetBSD_Version__, 82 .mi_class = MODULE_CLASS_MISC, 83 .mi_name = "netbsd" 84 }; 85 86 static module_t *module_active; 87 bool module_verbose_on; 88 #ifdef MODULAR_DEFAULT_AUTOLOAD 89 bool module_autoload_on = true; 90 #else 91 bool module_autoload_on = false; 92 #endif 93 u_int module_count; 94 u_int module_builtinlist; 95 u_int module_autotime = 10; 96 u_int module_gen = 1; 97 static kcondvar_t module_thread_cv; 98 static kmutex_t module_thread_lock; 99 static int module_thread_ticks; 100 int (*module_load_vfs_vec)(const char *, int, bool, module_t *, 101 prop_dictionary_t *) = (void *)eopnotsupp; 102 103 static kauth_listener_t module_listener; 104 105 static specificdata_domain_t module_specificdata_domain; 106 107 /* Ensure that the kernel's link set isn't empty. */ 108 static modinfo_t module_dummy; 109 __link_set_add_rodata(modules, module_dummy); 110 111 static module_t *module_newmodule(modsrc_t); 112 static void module_free(module_t *); 113 static void module_require_force(module_t *); 114 static int module_do_load(const char *, bool, int, prop_dictionary_t, 115 module_t **, modclass_t modclass, bool); 116 static int module_do_unload(const char *, bool); 117 static int module_do_builtin(const module_t *, const char *, module_t **, 118 prop_dictionary_t); 119 static int module_fetch_info(module_t *); 120 static void module_thread(void *); 121 122 static module_t *module_lookup(const char *); 123 static void module_enqueue(module_t *); 124 125 static bool module_merge_dicts(prop_dictionary_t, const prop_dictionary_t); 126 127 static void sysctl_module_setup(void); 128 static int sysctl_module_autotime(SYSCTLFN_PROTO); 129 130 static void module_callback_load(struct module *); 131 static void module_callback_unload(struct module *); 132 133 #define MODULE_CLASS_MATCH(mi, modclass) \ 134 ((modclass) == MODULE_CLASS_ANY || (modclass) == (mi)->mi_class) 135 136 static void 137 module_incompat(const modinfo_t *mi, int modclass) 138 { 139 module_error("incompatible module class %d for `%s' (wanted %d)", 140 mi->mi_class, mi->mi_name, modclass); 141 } 142 143 struct module * 144 module_kernel(void) 145 { 146 147 return module_netbsd; 148 } 149 150 /* 151 * module_error: 152 * 153 * Utility function: log an error. 154 */ 155 void 156 module_error(const char *fmt, ...) 157 { 158 va_list ap; 159 160 va_start(ap, fmt); 161 printf("WARNING: module error: "); 162 vprintf(fmt, ap); 163 printf("\n"); 164 va_end(ap); 165 } 166 167 /* 168 * module_print: 169 * 170 * Utility function: log verbose output. 171 */ 172 void 173 module_print(const char *fmt, ...) 174 { 175 va_list ap; 176 177 if (module_verbose_on) { 178 va_start(ap, fmt); 179 printf("DEBUG: module: "); 180 vprintf(fmt, ap); 181 printf("\n"); 182 va_end(ap); 183 } 184 } 185 186 /* 187 * module_name: 188 * 189 * Utility function: return the module's name. 190 */ 191 const char * 192 module_name(struct module *mod) 193 { 194 195 return mod->mod_info->mi_name; 196 } 197 198 /* 199 * module_source: 200 * 201 * Utility function: return the module's source. 202 */ 203 modsrc_t 204 module_source(struct module *mod) 205 { 206 207 return mod->mod_source; 208 } 209 210 static int 211 module_listener_cb(kauth_cred_t cred, kauth_action_t action, void *cookie, 212 void *arg0, void *arg1, void *arg2, void *arg3) 213 { 214 int result; 215 216 result = KAUTH_RESULT_DEFER; 217 218 if (action != KAUTH_SYSTEM_MODULE) 219 return result; 220 221 if ((uintptr_t)arg2 != 0) /* autoload */ 222 result = KAUTH_RESULT_ALLOW; 223 224 return result; 225 } 226 227 /* 228 * Allocate a new module_t 229 */ 230 static module_t * 231 module_newmodule(modsrc_t source) 232 { 233 module_t *mod; 234 235 mod = kmem_zalloc(sizeof(*mod), KM_SLEEP); 236 mod->mod_source = source; 237 specificdata_init(module_specificdata_domain, &mod->mod_sdref); 238 return mod; 239 } 240 241 /* 242 * Free a module_t 243 */ 244 static void 245 module_free(module_t *mod) 246 { 247 248 specificdata_fini(module_specificdata_domain, &mod->mod_sdref); 249 if (mod->mod_required) 250 kmem_free(mod->mod_required, mod->mod_arequired * 251 sizeof(module_t *)); 252 kmem_free(mod, sizeof(*mod)); 253 } 254 255 /* 256 * Require the -f (force) flag to load a module 257 */ 258 static void 259 module_require_force(struct module *mod) 260 { 261 SET(mod->mod_flags, MODFLG_MUST_FORCE); 262 } 263 264 /* 265 * Add modules to the builtin list. This can done at boottime or 266 * at runtime if the module is linked into the kernel with an 267 * external linker. All or none of the input will be handled. 268 * Optionally, the modules can be initialized. If they are not 269 * initialized, module_init_class() or module_load() can be used 270 * later, but these are not guaranteed to give atomic results. 271 */ 272 int 273 module_builtin_add(modinfo_t *const *mip, size_t nmodinfo, bool init) 274 { 275 struct module **modp = NULL, *mod_iter; 276 int rv = 0, i, mipskip; 277 278 if (init) { 279 rv = kauth_authorize_system(kauth_cred_get(), 280 KAUTH_SYSTEM_MODULE, 0, (void *)(uintptr_t)MODCTL_LOAD, 281 (void *)(uintptr_t)1, NULL); 282 if (rv) { 283 return rv; 284 } 285 } 286 287 for (i = 0, mipskip = 0; i < nmodinfo; i++) { 288 if (mip[i] == &module_dummy) { 289 KASSERT(nmodinfo > 0); 290 nmodinfo--; 291 } 292 } 293 if (nmodinfo == 0) 294 return 0; 295 296 modp = kmem_zalloc(sizeof(*modp) * nmodinfo, KM_SLEEP); 297 for (i = 0, mipskip = 0; i < nmodinfo; i++) { 298 if (mip[i+mipskip] == &module_dummy) { 299 mipskip++; 300 continue; 301 } 302 modp[i] = module_newmodule(MODULE_SOURCE_KERNEL); 303 modp[i]->mod_info = mip[i+mipskip]; 304 } 305 kernconfig_lock(); 306 307 /* do this in three stages for error recovery and atomicity */ 308 309 /* first check for presence */ 310 for (i = 0; i < nmodinfo; i++) { 311 TAILQ_FOREACH(mod_iter, &module_builtins, mod_chain) { 312 if (strcmp(mod_iter->mod_info->mi_name, 313 modp[i]->mod_info->mi_name) == 0) 314 break; 315 } 316 if (mod_iter) { 317 rv = EEXIST; 318 goto out; 319 } 320 321 if (module_lookup(modp[i]->mod_info->mi_name) != NULL) { 322 rv = EEXIST; 323 goto out; 324 } 325 } 326 327 /* then add to list */ 328 for (i = 0; i < nmodinfo; i++) { 329 TAILQ_INSERT_TAIL(&module_builtins, modp[i], mod_chain); 330 module_builtinlist++; 331 } 332 333 /* finally, init (if required) */ 334 if (init) { 335 for (i = 0; i < nmodinfo; i++) { 336 rv = module_do_builtin(modp[i], 337 modp[i]->mod_info->mi_name, NULL, NULL); 338 /* throw in the towel, recovery hard & not worth it */ 339 if (rv) 340 panic("%s: builtin module \"%s\" init failed:" 341 " %d", __func__, 342 modp[i]->mod_info->mi_name, rv); 343 } 344 } 345 346 out: 347 kernconfig_unlock(); 348 if (rv != 0) { 349 for (i = 0; i < nmodinfo; i++) { 350 if (modp[i]) 351 module_free(modp[i]); 352 } 353 } 354 kmem_free(modp, sizeof(*modp) * nmodinfo); 355 return rv; 356 } 357 358 /* 359 * Optionally fini and remove builtin module from the kernel. 360 * Note: the module will now be unreachable except via mi && builtin_add. 361 */ 362 int 363 module_builtin_remove(modinfo_t *mi, bool fini) 364 { 365 struct module *mod; 366 int rv = 0; 367 368 if (fini) { 369 rv = kauth_authorize_system(kauth_cred_get(), 370 KAUTH_SYSTEM_MODULE, 0, (void *)(uintptr_t)MODCTL_UNLOAD, 371 NULL, NULL); 372 if (rv) 373 return rv; 374 375 kernconfig_lock(); 376 rv = module_do_unload(mi->mi_name, true); 377 if (rv) { 378 goto out; 379 } 380 } else { 381 kernconfig_lock(); 382 } 383 TAILQ_FOREACH(mod, &module_builtins, mod_chain) { 384 if (strcmp(mod->mod_info->mi_name, mi->mi_name) == 0) 385 break; 386 } 387 if (mod) { 388 TAILQ_REMOVE(&module_builtins, mod, mod_chain); 389 module_builtinlist--; 390 } else { 391 KASSERT(fini == false); 392 rv = ENOENT; 393 } 394 395 out: 396 kernconfig_unlock(); 397 return rv; 398 } 399 400 /* 401 * module_init: 402 * 403 * Initialize the module subsystem. 404 */ 405 void 406 module_init(void) 407 { 408 __link_set_decl(modules, modinfo_t); 409 extern struct vm_map *module_map; 410 modinfo_t *const *mip; 411 int rv; 412 413 if (module_map == NULL) { 414 module_map = kernel_map; 415 } 416 cv_init(&module_thread_cv, "mod_unld"); 417 mutex_init(&module_thread_lock, MUTEX_DEFAULT, IPL_NONE); 418 TAILQ_INIT(&modcblist); 419 420 #ifdef MODULAR /* XXX */ 421 module_init_md(); 422 #endif 423 424 #ifdef KERNEL_DIR 425 const char *booted_kernel = get_booted_kernel(); 426 if (booted_kernel) { 427 char *ptr = strrchr(booted_kernel, '/'); 428 snprintf(module_base, sizeof(module_base), "/%.*s/modules", 429 (int)(ptr - booted_kernel), booted_kernel); 430 } else { 431 strlcpy(module_base, "/netbsd/modules", sizeof(module_base)); 432 printf("Cannot find kernel name, loading modules from \"%s\"\n", 433 module_base); 434 } 435 #else 436 if (!module_machine) 437 module_machine = machine; 438 #if __NetBSD_Version__ / 1000000 % 100 == 99 /* -current */ 439 snprintf(module_base, sizeof(module_base), "/stand/%s/%s/modules", 440 module_machine, osrelease); 441 #else /* release */ 442 snprintf(module_base, sizeof(module_base), "/stand/%s/%d.%d/modules", 443 module_machine, __NetBSD_Version__ / 100000000, 444 __NetBSD_Version__ / 1000000 % 100); 445 #endif 446 #endif 447 448 module_listener = kauth_listen_scope(KAUTH_SCOPE_SYSTEM, 449 module_listener_cb, NULL); 450 451 __link_set_foreach(mip, modules) { 452 if ((rv = module_builtin_add(mip, 1, false)) != 0) 453 module_error("builtin %s failed: %d\n", 454 (*mip)->mi_name, rv); 455 } 456 457 sysctl_module_setup(); 458 module_specificdata_domain = specificdata_domain_create(); 459 460 module_netbsd = module_newmodule(MODULE_SOURCE_KERNEL); 461 module_netbsd->mod_refcnt = 1; 462 module_netbsd->mod_info = &module_netbsd_modinfo; 463 } 464 465 /* 466 * module_start_unload_thread: 467 * 468 * Start the auto unload kthread. 469 */ 470 void 471 module_start_unload_thread(void) 472 { 473 int error; 474 475 error = kthread_create(PRI_VM, KTHREAD_MPSAFE, NULL, module_thread, 476 NULL, NULL, "modunload"); 477 if (error != 0) 478 panic("%s: %d", __func__, error); 479 } 480 481 /* 482 * module_builtin_require_force 483 * 484 * Require MODCTL_MUST_FORCE to load any built-in modules that have 485 * not yet been initialized 486 */ 487 void 488 module_builtin_require_force(void) 489 { 490 module_t *mod; 491 492 kernconfig_lock(); 493 TAILQ_FOREACH(mod, &module_builtins, mod_chain) { 494 module_require_force(mod); 495 } 496 kernconfig_unlock(); 497 } 498 499 static struct sysctllog *module_sysctllog; 500 501 static int 502 sysctl_module_autotime(SYSCTLFN_ARGS) 503 { 504 struct sysctlnode node; 505 int t, error; 506 507 t = *(int *)rnode->sysctl_data; 508 509 node = *rnode; 510 node.sysctl_data = &t; 511 error = sysctl_lookup(SYSCTLFN_CALL(&node)); 512 if (error || newp == NULL) 513 return (error); 514 515 if (t < 0) 516 return (EINVAL); 517 518 *(int *)rnode->sysctl_data = t; 519 return (0); 520 } 521 522 static void 523 sysctl_module_setup(void) 524 { 525 const struct sysctlnode *node = NULL; 526 527 sysctl_createv(&module_sysctllog, 0, NULL, &node, 528 CTLFLAG_PERMANENT, 529 CTLTYPE_NODE, "module", 530 SYSCTL_DESCR("Module options"), 531 NULL, 0, NULL, 0, 532 CTL_KERN, CTL_CREATE, CTL_EOL); 533 534 if (node == NULL) 535 return; 536 537 sysctl_createv(&module_sysctllog, 0, &node, NULL, 538 CTLFLAG_PERMANENT | CTLFLAG_READWRITE, 539 CTLTYPE_BOOL, "autoload", 540 SYSCTL_DESCR("Enable automatic load of modules"), 541 NULL, 0, &module_autoload_on, 0, 542 CTL_CREATE, CTL_EOL); 543 sysctl_createv(&module_sysctllog, 0, &node, NULL, 544 CTLFLAG_PERMANENT | CTLFLAG_READWRITE, 545 CTLTYPE_BOOL, "verbose", 546 SYSCTL_DESCR("Enable verbose output"), 547 NULL, 0, &module_verbose_on, 0, 548 CTL_CREATE, CTL_EOL); 549 sysctl_createv(&module_sysctllog, 0, &node, NULL, 550 CTLFLAG_PERMANENT | CTLFLAG_READONLY, 551 CTLTYPE_STRING, "path", 552 SYSCTL_DESCR("Default module load path"), 553 NULL, 0, module_base, 0, 554 CTL_CREATE, CTL_EOL); 555 sysctl_createv(&module_sysctllog, 0, &node, NULL, 556 CTLFLAG_PERMANENT | CTLFLAG_READWRITE, 557 CTLTYPE_INT, "autotime", 558 SYSCTL_DESCR("Auto-unload delay"), 559 sysctl_module_autotime, 0, &module_autotime, 0, 560 CTL_CREATE, CTL_EOL); 561 } 562 563 /* 564 * module_init_class: 565 * 566 * Initialize all built-in and pre-loaded modules of the 567 * specified class. 568 */ 569 void 570 module_init_class(modclass_t modclass) 571 { 572 TAILQ_HEAD(, module) bi_fail = TAILQ_HEAD_INITIALIZER(bi_fail); 573 module_t *mod; 574 modinfo_t *mi; 575 576 kernconfig_lock(); 577 /* 578 * Builtins first. These will not depend on pre-loaded modules 579 * (because the kernel would not link). 580 */ 581 do { 582 TAILQ_FOREACH(mod, &module_builtins, mod_chain) { 583 mi = mod->mod_info; 584 if (!MODULE_CLASS_MATCH(mi, modclass)) 585 continue; 586 /* 587 * If initializing a builtin module fails, don't try 588 * to load it again. But keep it around and queue it 589 * on the builtins list after we're done with module 590 * init. Don't set it to MODFLG_MUST_FORCE in case a 591 * future attempt to initialize can be successful. 592 * (If the module has previously been set to 593 * MODFLG_MUST_FORCE, don't try to override that!) 594 */ 595 if (ISSET(mod->mod_flags, MODFLG_MUST_FORCE) || 596 module_do_builtin(mod, mi->mi_name, NULL, 597 NULL) != 0) { 598 TAILQ_REMOVE(&module_builtins, mod, mod_chain); 599 TAILQ_INSERT_TAIL(&bi_fail, mod, mod_chain); 600 } 601 break; 602 } 603 } while (mod != NULL); 604 605 /* 606 * Now preloaded modules. These will be pulled off the 607 * list as we call module_do_load(); 608 */ 609 do { 610 TAILQ_FOREACH(mod, &module_bootlist, mod_chain) { 611 mi = mod->mod_info; 612 if (!MODULE_CLASS_MATCH(mi, modclass)) 613 continue; 614 module_do_load(mi->mi_name, false, 0, NULL, NULL, 615 modclass, false); 616 break; 617 } 618 } while (mod != NULL); 619 620 /* return failed builtin modules to builtin list */ 621 while ((mod = TAILQ_FIRST(&bi_fail)) != NULL) { 622 TAILQ_REMOVE(&bi_fail, mod, mod_chain); 623 TAILQ_INSERT_TAIL(&module_builtins, mod, mod_chain); 624 } 625 626 kernconfig_unlock(); 627 } 628 629 /* 630 * module_compatible: 631 * 632 * Return true if the two supplied kernel versions are said to 633 * have the same binary interface for kernel code. The entire 634 * version is signficant for the development tree (-current), 635 * major and minor versions are significant for official 636 * releases of the system. 637 */ 638 bool 639 module_compatible(int v1, int v2) 640 { 641 642 #if __NetBSD_Version__ / 1000000 % 100 == 99 /* -current */ 643 return v1 == v2; 644 #else /* release */ 645 return abs(v1 - v2) < 10000; 646 #endif 647 } 648 649 /* 650 * module_load: 651 * 652 * Load a single module from the file system. 653 */ 654 int 655 module_load(const char *filename, int flags, prop_dictionary_t props, 656 modclass_t modclass) 657 { 658 module_t *mod; 659 int error; 660 661 /* Test if we already have the module loaded before 662 * authorizing so we have the opportunity to return EEXIST. */ 663 kernconfig_lock(); 664 mod = module_lookup(filename); 665 if (mod != NULL) { 666 module_print("%s module `%s' already loaded", 667 "requested", filename); 668 error = EEXIST; 669 goto out; 670 } 671 672 /* Authorize. */ 673 error = kauth_authorize_system(kauth_cred_get(), KAUTH_SYSTEM_MODULE, 674 0, (void *)(uintptr_t)MODCTL_LOAD, NULL, NULL); 675 if (error != 0) 676 goto out; 677 678 error = module_do_load(filename, false, flags, props, NULL, modclass, 679 false); 680 681 out: 682 kernconfig_unlock(); 683 return error; 684 } 685 686 /* 687 * module_autoload: 688 * 689 * Load a single module from the file system, system initiated. 690 */ 691 int 692 module_autoload(const char *filename, modclass_t modclass) 693 { 694 int error; 695 struct proc *p = curlwp->l_proc; 696 697 kernconfig_lock(); 698 699 /* Nothing if the user has disabled it. */ 700 if (!module_autoload_on) { 701 kernconfig_unlock(); 702 return EPERM; 703 } 704 705 /* Disallow path separators and magic symlinks. */ 706 if (strchr(filename, '/') != NULL || strchr(filename, '@') != NULL || 707 strchr(filename, '.') != NULL) { 708 kernconfig_unlock(); 709 return EPERM; 710 } 711 712 /* Authorize. */ 713 error = kauth_authorize_system(kauth_cred_get(), KAUTH_SYSTEM_MODULE, 714 0, (void *)(uintptr_t)MODCTL_LOAD, (void *)(uintptr_t)1, NULL); 715 716 if (error == 0) 717 error = module_do_load(filename, false, 0, NULL, NULL, modclass, 718 true); 719 720 module_print("Autoload for `%s' requested by pid %d (%s), status %d", 721 filename, p->p_pid, p->p_comm, error); 722 kernconfig_unlock(); 723 return error; 724 } 725 726 /* 727 * module_unload: 728 * 729 * Find and unload a module by name. 730 */ 731 int 732 module_unload(const char *name) 733 { 734 int error; 735 736 /* Authorize. */ 737 error = kauth_authorize_system(kauth_cred_get(), KAUTH_SYSTEM_MODULE, 738 0, (void *)(uintptr_t)MODCTL_UNLOAD, NULL, NULL); 739 if (error != 0) { 740 return error; 741 } 742 743 kernconfig_lock(); 744 error = module_do_unload(name, true); 745 kernconfig_unlock(); 746 747 return error; 748 } 749 750 /* 751 * module_lookup: 752 * 753 * Look up a module by name. 754 */ 755 module_t * 756 module_lookup(const char *name) 757 { 758 module_t *mod; 759 760 KASSERT(kernconfig_is_held()); 761 762 TAILQ_FOREACH(mod, &module_list, mod_chain) { 763 if (strcmp(mod->mod_info->mi_name, name) == 0) 764 break; 765 } 766 767 return mod; 768 } 769 770 /* 771 * module_hold: 772 * 773 * Add a single reference to a module. It's the caller's 774 * responsibility to ensure that the reference is dropped 775 * later. 776 */ 777 void 778 module_hold(module_t *mod) 779 { 780 781 kernconfig_lock(); 782 mod->mod_refcnt++; 783 kernconfig_unlock(); 784 } 785 786 /* 787 * module_rele: 788 * 789 * Release a reference acquired with module_hold(). 790 */ 791 void 792 module_rele(module_t *mod) 793 { 794 795 kernconfig_lock(); 796 KASSERT(mod->mod_refcnt > 0); 797 mod->mod_refcnt--; 798 kernconfig_unlock(); 799 } 800 801 /* 802 * module_enqueue: 803 * 804 * Put a module onto the global list and update counters. 805 */ 806 void 807 module_enqueue(module_t *mod) 808 { 809 int i; 810 811 KASSERT(kernconfig_is_held()); 812 813 /* 814 * Put new entry at the head of the queue so autounload can unload 815 * requisite modules with only one pass through the queue. 816 */ 817 TAILQ_INSERT_HEAD(&module_list, mod, mod_chain); 818 if (mod->mod_nrequired) { 819 820 /* Add references to the requisite modules. */ 821 for (i = 0; i < mod->mod_nrequired; i++) { 822 KASSERT((*mod->mod_required)[i] != NULL); 823 (*mod->mod_required)[i]->mod_refcnt++; 824 } 825 } 826 module_count++; 827 module_gen++; 828 } 829 830 /* 831 * Our array of required module pointers starts with zero entries. If we 832 * need to add a new entry, and the list is already full, we reallocate a 833 * larger array, adding MAXMODDEPS entries. 834 */ 835 static void 836 alloc_required(module_t *mod) 837 { 838 module_t *(*new)[], *(*old)[]; 839 int areq; 840 int i; 841 842 if (mod->mod_nrequired >= mod->mod_arequired) { 843 areq = mod->mod_arequired + MAXMODDEPS; 844 old = mod->mod_required; 845 new = kmem_zalloc(areq * sizeof(module_t *), KM_SLEEP); 846 for (i = 0; i < mod->mod_arequired; i++) 847 (*new)[i] = (*old)[i]; 848 mod->mod_required = new; 849 if (old) 850 kmem_free(old, mod->mod_arequired * sizeof(module_t *)); 851 mod->mod_arequired = areq; 852 } 853 } 854 855 /* 856 * module_do_builtin: 857 * 858 * Initialize a module from the list of modules that are 859 * already linked into the kernel. 860 */ 861 static int 862 module_do_builtin(const module_t *pmod, const char *name, module_t **modp, 863 prop_dictionary_t props) 864 { 865 const char *p, *s; 866 char buf[MAXMODNAME]; 867 modinfo_t *mi = NULL; 868 module_t *mod, *mod2, *mod_loaded, *prev_active; 869 size_t len; 870 int error; 871 872 KASSERT(kernconfig_is_held()); 873 874 /* 875 * Search the list to see if we have a module by this name. 876 */ 877 TAILQ_FOREACH(mod, &module_builtins, mod_chain) { 878 if (strcmp(mod->mod_info->mi_name, name) == 0) { 879 mi = mod->mod_info; 880 break; 881 } 882 } 883 884 /* 885 * Check to see if already loaded. This might happen if we 886 * were already loaded as a dependency. 887 */ 888 if ((mod_loaded = module_lookup(name)) != NULL) { 889 KASSERT(mod == NULL); 890 if (modp) 891 *modp = mod_loaded; 892 return 0; 893 } 894 895 /* Note! This is from TAILQ, not immediate above */ 896 if (mi == NULL) { 897 /* 898 * XXX: We'd like to panic here, but currently in some 899 * cases (such as nfsserver + nfs), the dependee can be 900 * successfully linked without the dependencies. 901 */ 902 module_error("built-in module %s can't find builtin " 903 "dependency `%s'", pmod->mod_info->mi_name, name); 904 return ENOENT; 905 } 906 907 /* 908 * Initialize pre-requisites. 909 */ 910 KASSERT(mod->mod_required == NULL); 911 KASSERT(mod->mod_arequired == 0); 912 KASSERT(mod->mod_nrequired == 0); 913 if (mi->mi_required != NULL) { 914 for (s = mi->mi_required; *s != '\0'; s = p) { 915 if (*s == ',') 916 s++; 917 p = s; 918 while (*p != '\0' && *p != ',') 919 p++; 920 len = uimin(p - s + 1, sizeof(buf)); 921 strlcpy(buf, s, len); 922 if (buf[0] == '\0') 923 break; 924 alloc_required(mod); 925 error = module_do_builtin(mod, buf, &mod2, NULL); 926 if (error != 0) { 927 module_error("built-in module %s prerequisite " 928 "%s failed, error %d", name, buf, error); 929 goto fail; 930 } 931 (*mod->mod_required)[mod->mod_nrequired++] = mod2; 932 } 933 } 934 935 /* 936 * Try to initialize the module. 937 */ 938 prev_active = module_active; 939 module_active = mod; 940 error = (*mi->mi_modcmd)(MODULE_CMD_INIT, props); 941 module_active = prev_active; 942 if (error != 0) { 943 module_error("built-in module %s failed its MODULE_CMD_INIT, " 944 "error %d", mi->mi_name, error); 945 goto fail; 946 } 947 948 /* load always succeeds after this point */ 949 950 TAILQ_REMOVE(&module_builtins, mod, mod_chain); 951 module_builtinlist--; 952 if (modp != NULL) { 953 *modp = mod; 954 } 955 module_enqueue(mod); 956 return 0; 957 958 fail: 959 if (mod->mod_required) 960 kmem_free(mod->mod_required, mod->mod_arequired * 961 sizeof(module_t *)); 962 mod->mod_arequired = 0; 963 mod->mod_nrequired = 0; 964 mod->mod_required = NULL; 965 return error; 966 } 967 968 /* 969 * module_load_sysctl 970 * 971 * Check to see if a non-builtin module has any SYSCTL_SETUP() routine(s) 972 * registered. If so, call it (them). 973 */ 974 975 static void 976 module_load_sysctl(module_t *mod) 977 { 978 void (**ls_funcp)(struct sysctllog **); 979 void *ls_start; 980 size_t ls_size, count; 981 int error; 982 983 /* 984 * Built-in modules don't have a mod_kobj so we cannot search 985 * for their link_set_sysctl_funcs 986 */ 987 if (mod->mod_source == MODULE_SOURCE_KERNEL) 988 return; 989 990 error = kobj_find_section(mod->mod_kobj, "link_set_sysctl_funcs", 991 &ls_start, &ls_size); 992 if (error == 0) { 993 count = ls_size / sizeof(ls_start); 994 ls_funcp = ls_start; 995 while (count--) { 996 (**ls_funcp)(&mod->mod_sysctllog); 997 ls_funcp++; 998 } 999 } 1000 } 1001 1002 /* 1003 * module_load_evcnt 1004 * 1005 * Check to see if a non-builtin module has any static evcnt's defined; 1006 * if so, attach them. 1007 */ 1008 1009 static void 1010 module_load_evcnt(module_t *mod) 1011 { 1012 struct evcnt * const *ls_evp; 1013 void *ls_start; 1014 size_t ls_size, count; 1015 int error; 1016 1017 /* 1018 * Built-in modules' static evcnt stuff will be handled 1019 * automatically as part of general kernel initialization 1020 */ 1021 if (mod->mod_source == MODULE_SOURCE_KERNEL) 1022 return; 1023 1024 error = kobj_find_section(mod->mod_kobj, "link_set_evcnts", 1025 &ls_start, &ls_size); 1026 if (error == 0) { 1027 count = ls_size / sizeof(*ls_evp); 1028 ls_evp = ls_start; 1029 while (count--) { 1030 evcnt_attach_static(*ls_evp++); 1031 } 1032 } 1033 } 1034 1035 /* 1036 * module_unload_evcnt 1037 * 1038 * Check to see if a non-builtin module has any static evcnt's defined; 1039 * if so, detach them. 1040 */ 1041 1042 static void 1043 module_unload_evcnt(module_t *mod) 1044 { 1045 struct evcnt * const *ls_evp; 1046 void *ls_start; 1047 size_t ls_size, count; 1048 int error; 1049 1050 /* 1051 * Built-in modules' static evcnt stuff will be handled 1052 * automatically as part of general kernel initialization 1053 */ 1054 if (mod->mod_source == MODULE_SOURCE_KERNEL) 1055 return; 1056 1057 error = kobj_find_section(mod->mod_kobj, "link_set_evcnts", 1058 &ls_start, &ls_size); 1059 if (error == 0) { 1060 count = ls_size / sizeof(*ls_evp); 1061 ls_evp = (void *)((char *)ls_start + ls_size); 1062 while (count--) { 1063 evcnt_detach(*--ls_evp); 1064 } 1065 } 1066 } 1067 1068 /* 1069 * module_do_load: 1070 * 1071 * Helper routine: load a module from the file system, or one 1072 * pushed by the boot loader. 1073 */ 1074 static int 1075 module_do_load(const char *name, bool isdep, int flags, 1076 prop_dictionary_t props, module_t **modp, modclass_t modclass, 1077 bool autoload) 1078 { 1079 /* The pending list for this level of recursion */ 1080 TAILQ_HEAD(pending_t, module); 1081 struct pending_t *pending; 1082 struct pending_t new_pending = TAILQ_HEAD_INITIALIZER(new_pending); 1083 1084 /* The stack of pending lists */ 1085 static SLIST_HEAD(pend_head, pend_entry) pend_stack = 1086 SLIST_HEAD_INITIALIZER(pend_stack); 1087 struct pend_entry { 1088 SLIST_ENTRY(pend_entry) pe_entry; 1089 struct pending_t *pe_pending; 1090 } my_pend_entry; 1091 1092 modinfo_t *mi; 1093 module_t *mod, *mod2, *prev_active; 1094 prop_dictionary_t filedict; 1095 char buf[MAXMODNAME]; 1096 const char *s, *p; 1097 int error; 1098 size_t len; 1099 1100 KASSERT(kernconfig_is_held()); 1101 1102 filedict = NULL; 1103 error = 0; 1104 1105 /* 1106 * Set up the pending list for this entry. If this is an 1107 * internal entry (for a dependency), then use the same list 1108 * as for the outer call; otherwise, it's an external entry 1109 * (possibly recursive, ie a module's xxx_modcmd(init, ...) 1110 * routine called us), so use the locally allocated list. In 1111 * either case, add it to our stack. 1112 */ 1113 if (isdep) { 1114 KASSERT(SLIST_FIRST(&pend_stack) != NULL); 1115 pending = SLIST_FIRST(&pend_stack)->pe_pending; 1116 } else 1117 pending = &new_pending; 1118 my_pend_entry.pe_pending = pending; 1119 SLIST_INSERT_HEAD(&pend_stack, &my_pend_entry, pe_entry); 1120 1121 /* 1122 * Search the list of disabled builtins first. 1123 */ 1124 TAILQ_FOREACH(mod, &module_builtins, mod_chain) { 1125 if (strcmp(mod->mod_info->mi_name, name) == 0) { 1126 break; 1127 } 1128 } 1129 if (mod) { 1130 if (ISSET(mod->mod_flags, MODFLG_MUST_FORCE) && 1131 !ISSET(flags, MODCTL_LOAD_FORCE)) { 1132 if (!autoload) { 1133 module_error("use -f to reinstate " 1134 "builtin module `%s'", name); 1135 } 1136 SLIST_REMOVE_HEAD(&pend_stack, pe_entry); 1137 return EPERM; 1138 } else { 1139 SLIST_REMOVE_HEAD(&pend_stack, pe_entry); 1140 error = module_do_builtin(mod, name, modp, props); 1141 return error; 1142 } 1143 } 1144 1145 /* 1146 * Load the module and link. Before going to the file system, 1147 * scan the list of modules loaded by the boot loader. 1148 */ 1149 TAILQ_FOREACH(mod, &module_bootlist, mod_chain) { 1150 if (strcmp(mod->mod_info->mi_name, name) == 0) { 1151 TAILQ_REMOVE(&module_bootlist, mod, mod_chain); 1152 break; 1153 } 1154 } 1155 if (mod != NULL) { 1156 TAILQ_INSERT_TAIL(pending, mod, mod_chain); 1157 } else { 1158 /* 1159 * Check to see if module is already present. 1160 */ 1161 mod = module_lookup(name); 1162 if (mod != NULL) { 1163 if (modp != NULL) { 1164 *modp = mod; 1165 } 1166 module_print("%s module `%s' already loaded", 1167 isdep ? "dependent" : "requested", name); 1168 SLIST_REMOVE_HEAD(&pend_stack, pe_entry); 1169 return EEXIST; 1170 } 1171 1172 mod = module_newmodule(MODULE_SOURCE_FILESYS); 1173 if (mod == NULL) { 1174 module_error("out of memory for `%s'", name); 1175 SLIST_REMOVE_HEAD(&pend_stack, pe_entry); 1176 return ENOMEM; 1177 } 1178 1179 error = module_load_vfs_vec(name, flags, autoload, mod, 1180 &filedict); 1181 if (error != 0) { 1182 #ifdef DEBUG 1183 /* 1184 * The exec class of modules contains a list of 1185 * modules that is the union of all the modules 1186 * available for each architecture, so we don't 1187 * print an error if they are missing. 1188 */ 1189 if ((modclass != MODULE_CLASS_EXEC || error != ENOENT) 1190 && root_device != NULL) 1191 module_error("vfs load failed for `%s', " 1192 "error %d", name, error); 1193 #endif 1194 SLIST_REMOVE_HEAD(&pend_stack, pe_entry); 1195 module_free(mod); 1196 return error; 1197 } 1198 TAILQ_INSERT_TAIL(pending, mod, mod_chain); 1199 1200 error = module_fetch_info(mod); 1201 if (error != 0) { 1202 module_error("cannot fetch info for `%s', error %d", 1203 name, error); 1204 goto fail; 1205 } 1206 } 1207 1208 /* 1209 * Check compatibility. 1210 */ 1211 mi = mod->mod_info; 1212 if (strnlen(mi->mi_name, MAXMODNAME) >= MAXMODNAME) { 1213 error = EINVAL; 1214 module_error("module name `%s' longer than %d", mi->mi_name, 1215 MAXMODNAME); 1216 goto fail; 1217 } 1218 if (mi->mi_class <= MODULE_CLASS_ANY || 1219 mi->mi_class >= MODULE_CLASS_MAX) { 1220 error = EINVAL; 1221 module_error("module `%s' has invalid class %d", 1222 mi->mi_name, mi->mi_class); 1223 goto fail; 1224 } 1225 if (!module_compatible(mi->mi_version, __NetBSD_Version__)) { 1226 module_error("module `%s' built for `%d', system `%d'", 1227 mi->mi_name, mi->mi_version, __NetBSD_Version__); 1228 if (ISSET(flags, MODCTL_LOAD_FORCE)) { 1229 module_error("forced load, system may be unstable"); 1230 } else { 1231 error = EPROGMISMATCH; 1232 goto fail; 1233 } 1234 } 1235 1236 /* 1237 * If a specific kind of module was requested, ensure that we have 1238 * a match. 1239 */ 1240 if (!MODULE_CLASS_MATCH(mi, modclass)) { 1241 module_incompat(mi, modclass); 1242 error = ENOENT; 1243 goto fail; 1244 } 1245 1246 /* 1247 * If loading a dependency, `name' is a plain module name. 1248 * The name must match. 1249 */ 1250 if (isdep && strcmp(mi->mi_name, name) != 0) { 1251 module_error("dependency name mismatch (`%s' != `%s')", 1252 name, mi->mi_name); 1253 error = ENOENT; 1254 goto fail; 1255 } 1256 1257 /* 1258 * If we loaded a module from the filesystem, check the actual 1259 * module name (from the modinfo_t) to ensure another module 1260 * with the same name doesn't already exist. (There's no 1261 * guarantee the filename will match the module name, and the 1262 * dup-symbols check may not be sufficient.) 1263 */ 1264 if (mod->mod_source == MODULE_SOURCE_FILESYS) { 1265 mod2 = module_lookup(mod->mod_info->mi_name); 1266 if ( mod2 && mod2 != mod) { 1267 module_error("module with name `%s' already loaded", 1268 mod2->mod_info->mi_name); 1269 error = EEXIST; 1270 if (modp != NULL) 1271 *modp = mod2; 1272 goto fail; 1273 } 1274 } 1275 1276 /* 1277 * Block circular dependencies. 1278 */ 1279 TAILQ_FOREACH(mod2, pending, mod_chain) { 1280 if (mod == mod2) { 1281 continue; 1282 } 1283 if (strcmp(mod2->mod_info->mi_name, mi->mi_name) == 0) { 1284 error = EDEADLK; 1285 module_error("circular dependency detected for `%s'", 1286 mi->mi_name); 1287 goto fail; 1288 } 1289 } 1290 1291 /* 1292 * Now try to load any requisite modules. 1293 */ 1294 if (mi->mi_required != NULL) { 1295 mod->mod_arequired = 0; 1296 for (s = mi->mi_required; *s != '\0'; s = p) { 1297 if (*s == ',') 1298 s++; 1299 p = s; 1300 while (*p != '\0' && *p != ',') 1301 p++; 1302 len = p - s + 1; 1303 if (len >= MAXMODNAME) { 1304 error = EINVAL; 1305 module_error("required module name `%s' " 1306 "longer than %d", mi->mi_required, 1307 MAXMODNAME); 1308 goto fail; 1309 } 1310 strlcpy(buf, s, len); 1311 if (buf[0] == '\0') 1312 break; 1313 alloc_required(mod); 1314 if (strcmp(buf, mi->mi_name) == 0) { 1315 error = EDEADLK; 1316 module_error("self-dependency detected for " 1317 "`%s'", mi->mi_name); 1318 goto fail; 1319 } 1320 error = module_do_load(buf, true, flags, NULL, 1321 &mod2, MODULE_CLASS_ANY, true); 1322 if (error != 0 && error != EEXIST) { 1323 module_error("recursive load failed for `%s' " 1324 "(`%s' required), error %d", mi->mi_name, 1325 buf, error); 1326 goto fail; 1327 } 1328 (*mod->mod_required)[mod->mod_nrequired++] = mod2; 1329 } 1330 } 1331 1332 /* 1333 * We loaded all needed modules successfully: perform global 1334 * relocations and initialize. 1335 */ 1336 { 1337 char xname[MAXMODNAME]; 1338 1339 /* 1340 * In case of error the entire module is gone, so we 1341 * need to save its name for possible error report. 1342 */ 1343 1344 strlcpy(xname, mi->mi_name, MAXMODNAME); 1345 error = kobj_affix(mod->mod_kobj, mi->mi_name); 1346 if (error != 0) { 1347 module_error("unable to affix module `%s', error %d", 1348 xname, error); 1349 goto fail2; 1350 } 1351 } 1352 1353 if (filedict) { 1354 if (!module_merge_dicts(filedict, props)) { 1355 module_error("module properties failed for %s", name); 1356 error = EINVAL; 1357 goto fail; 1358 } 1359 } 1360 1361 prev_active = module_active; 1362 module_active = mod; 1363 error = (*mi->mi_modcmd)(MODULE_CMD_INIT, filedict ? filedict : props); 1364 module_active = prev_active; 1365 if (filedict) { 1366 prop_object_release(filedict); 1367 filedict = NULL; 1368 } 1369 if (error != 0) { 1370 module_error("modcmd(CMD_INIT) failed for `%s', error %d", 1371 mi->mi_name, error); 1372 goto fail; 1373 } 1374 1375 /* 1376 * If a recursive load already added a module with the same 1377 * name, abort. 1378 */ 1379 mod2 = module_lookup(mi->mi_name); 1380 if (mod2 && mod2 != mod) { 1381 module_error("recursive load causes duplicate module `%s'", 1382 mi->mi_name); 1383 error = EEXIST; 1384 goto fail1; 1385 } 1386 1387 module_load_sysctl(mod); /* Set-up module's sysctl if any */ 1388 module_load_evcnt(mod); /* Attach any static evcnt needed */ 1389 1390 /* 1391 * Good, the module loaded successfully. Put it onto the 1392 * list and add references to its requisite modules. 1393 */ 1394 TAILQ_REMOVE(pending, mod, mod_chain); 1395 module_enqueue(mod); 1396 if (modp != NULL) { 1397 *modp = mod; 1398 } 1399 if (autoload && module_autotime > 0) { 1400 /* 1401 * Arrange to try unloading the module after 1402 * a short delay unless auto-unload is disabled. 1403 */ 1404 mod->mod_autotime = time_second + module_autotime; 1405 SET(mod->mod_flags, MODFLG_AUTO_LOADED); 1406 module_thread_kick(); 1407 } 1408 SLIST_REMOVE_HEAD(&pend_stack, pe_entry); 1409 module_print("module `%s' loaded successfully", mi->mi_name); 1410 module_callback_load(mod); 1411 return 0; 1412 1413 fail1: 1414 (*mi->mi_modcmd)(MODULE_CMD_FINI, NULL); 1415 fail: 1416 kobj_unload(mod->mod_kobj); 1417 fail2: 1418 if (filedict != NULL) { 1419 prop_object_release(filedict); 1420 filedict = NULL; 1421 } 1422 TAILQ_REMOVE(pending, mod, mod_chain); 1423 SLIST_REMOVE_HEAD(&pend_stack, pe_entry); 1424 module_free(mod); 1425 return error; 1426 } 1427 1428 /* 1429 * module_do_unload: 1430 * 1431 * Helper routine: do the dirty work of unloading a module. 1432 */ 1433 static int 1434 module_do_unload(const char *name, bool load_requires_force) 1435 { 1436 module_t *mod, *prev_active; 1437 int error; 1438 u_int i; 1439 1440 KASSERT(kernconfig_is_held()); 1441 KASSERT(name != NULL); 1442 1443 module_print("unload requested for '%s' (%s)", name, 1444 load_requires_force ? "TRUE" : "FALSE"); 1445 mod = module_lookup(name); 1446 if (mod == NULL) { 1447 module_error("module `%s' not found", name); 1448 return ENOENT; 1449 } 1450 if (mod->mod_refcnt != 0) { 1451 module_print("module `%s' busy (%d refs)", name, 1452 mod->mod_refcnt); 1453 return EBUSY; 1454 } 1455 1456 /* 1457 * Builtin secmodels are there to stay. 1458 */ 1459 if (mod->mod_source == MODULE_SOURCE_KERNEL && 1460 mod->mod_info->mi_class == MODULE_CLASS_SECMODEL) { 1461 module_print("cannot unload built-in secmodel module `%s'", 1462 name); 1463 return EPERM; 1464 } 1465 1466 prev_active = module_active; 1467 module_active = mod; 1468 module_callback_unload(mod); 1469 1470 /* 1471 * If there were any registered SYSCTL_SETUP funcs, make sure 1472 * we release the sysctl entries 1473 */ 1474 if (mod->mod_sysctllog) { 1475 sysctl_teardown(&mod->mod_sysctllog); 1476 } 1477 module_unload_evcnt(mod); 1478 error = (*mod->mod_info->mi_modcmd)(MODULE_CMD_FINI, NULL); 1479 module_active = prev_active; 1480 if (error != 0) { 1481 module_load_sysctl(mod); /* re-enable sysctl stuff */ 1482 module_load_evcnt(mod); /* and reenable evcnts */ 1483 module_print("cannot unload module `%s' error=%d", name, 1484 error); 1485 return error; 1486 } 1487 module_count--; 1488 TAILQ_REMOVE(&module_list, mod, mod_chain); 1489 for (i = 0; i < mod->mod_nrequired; i++) { 1490 (*mod->mod_required)[i]->mod_refcnt--; 1491 } 1492 module_print("unloaded module `%s'", name); 1493 if (mod->mod_kobj != NULL) { 1494 kobj_unload(mod->mod_kobj); 1495 } 1496 if (mod->mod_source == MODULE_SOURCE_KERNEL) { 1497 if (mod->mod_required != NULL) { 1498 /* 1499 * release "required" resources - will be re-parsed 1500 * if the module is re-enabled 1501 */ 1502 kmem_free(mod->mod_required, 1503 mod->mod_arequired * sizeof(module_t *)); 1504 mod->mod_nrequired = 0; 1505 mod->mod_arequired = 0; 1506 mod->mod_required = NULL; 1507 } 1508 if (load_requires_force) 1509 module_require_force(mod); 1510 TAILQ_INSERT_TAIL(&module_builtins, mod, mod_chain); 1511 module_builtinlist++; 1512 } else { 1513 module_free(mod); 1514 } 1515 module_gen++; 1516 1517 return 0; 1518 } 1519 1520 /* 1521 * module_prime: 1522 * 1523 * Push a module loaded by the bootloader onto our internal 1524 * list. 1525 */ 1526 int 1527 module_prime(const char *name, void *base, size_t size) 1528 { 1529 __link_set_decl(modules, modinfo_t); 1530 modinfo_t *const *mip; 1531 module_t *mod; 1532 int error; 1533 1534 /* Check for module name same as a built-in module */ 1535 1536 __link_set_foreach(mip, modules) { 1537 if (*mip == &module_dummy) 1538 continue; 1539 if (strcmp((*mip)->mi_name, name) == 0) { 1540 module_error("module `%s' pushed by boot loader " 1541 "already exists", name); 1542 return EEXIST; 1543 } 1544 } 1545 1546 /* Also eliminate duplicate boolist entries */ 1547 1548 TAILQ_FOREACH(mod, &module_bootlist, mod_chain) { 1549 if (strcmp(mod->mod_info->mi_name, name) == 0) { 1550 module_error("duplicate bootlist entry for module " 1551 "`%s'", name); 1552 return EEXIST; 1553 } 1554 } 1555 1556 mod = module_newmodule(MODULE_SOURCE_BOOT); 1557 if (mod == NULL) { 1558 return ENOMEM; 1559 } 1560 1561 error = kobj_load_mem(&mod->mod_kobj, name, base, size); 1562 if (error != 0) { 1563 module_free(mod); 1564 module_error("unable to load `%s' pushed by boot loader, " 1565 "error %d", name, error); 1566 return error; 1567 } 1568 error = module_fetch_info(mod); 1569 if (error != 0) { 1570 kobj_unload(mod->mod_kobj); 1571 module_free(mod); 1572 module_error("unable to fetch_info for `%s' pushed by boot " 1573 "loader, error %d", name, error); 1574 return error; 1575 } 1576 1577 TAILQ_INSERT_TAIL(&module_bootlist, mod, mod_chain); 1578 1579 return 0; 1580 } 1581 1582 /* 1583 * module_fetch_into: 1584 * 1585 * Fetch modinfo record from a loaded module. 1586 */ 1587 static int 1588 module_fetch_info(module_t *mod) 1589 { 1590 int error; 1591 void *addr; 1592 size_t size; 1593 1594 /* 1595 * Find module info record and check compatibility. 1596 */ 1597 error = kobj_find_section(mod->mod_kobj, "link_set_modules", 1598 &addr, &size); 1599 if (error != 0) { 1600 module_error("`link_set_modules' section not present, " 1601 "error %d", error); 1602 return error; 1603 } 1604 if (size != sizeof(modinfo_t **)) { 1605 module_error("`link_set_modules' section wrong size " 1606 "(got %zu, wanted %zu)", size, sizeof(modinfo_t **)); 1607 return ENOEXEC; 1608 } 1609 mod->mod_info = *(modinfo_t **)addr; 1610 1611 return 0; 1612 } 1613 1614 /* 1615 * module_find_section: 1616 * 1617 * Allows a module that is being initialized to look up a section 1618 * within its ELF object. 1619 */ 1620 int 1621 module_find_section(const char *name, void **addr, size_t *size) 1622 { 1623 1624 KASSERT(kernconfig_is_held()); 1625 KASSERT(module_active != NULL); 1626 1627 return kobj_find_section(module_active->mod_kobj, name, addr, size); 1628 } 1629 1630 /* 1631 * module_thread: 1632 * 1633 * Automatically unload modules. We try once to unload autoloaded 1634 * modules after module_autotime seconds. If the system is under 1635 * severe memory pressure, we'll try unloading all modules, else if 1636 * module_autotime is zero, we don't try to unload, even if the 1637 * module was previously scheduled for unload. 1638 */ 1639 static void 1640 module_thread(void *cookie) 1641 { 1642 module_t *mod, *next; 1643 modinfo_t *mi; 1644 int error; 1645 1646 for (;;) { 1647 kernconfig_lock(); 1648 for (mod = TAILQ_FIRST(&module_list); mod != NULL; mod = next) { 1649 next = TAILQ_NEXT(mod, mod_chain); 1650 1651 /* skip built-in modules */ 1652 if (mod->mod_source == MODULE_SOURCE_KERNEL) 1653 continue; 1654 /* skip modules that weren't auto-loaded */ 1655 if (!ISSET(mod->mod_flags, MODFLG_AUTO_LOADED)) 1656 continue; 1657 1658 if (uvm_availmem(false) < uvmexp.freemin) { 1659 module_thread_ticks = hz; 1660 } else if (module_autotime == 0 || 1661 mod->mod_autotime == 0) { 1662 continue; 1663 } else if (time_second < mod->mod_autotime) { 1664 module_thread_ticks = hz; 1665 continue; 1666 } else { 1667 mod->mod_autotime = 0; 1668 } 1669 1670 /* 1671 * If this module wants to avoid autounload then 1672 * skip it. Some modules can ping-pong in and out 1673 * because their use is transient but often. 1674 * Example: exec_script. 1675 */ 1676 mi = mod->mod_info; 1677 error = (*mi->mi_modcmd)(MODULE_CMD_AUTOUNLOAD, NULL); 1678 if (error == 0 || error == ENOTTY) { 1679 (void)module_do_unload(mi->mi_name, false); 1680 } else 1681 module_print("module `%s' declined to be " 1682 "auto-unloaded error=%d", mi->mi_name, 1683 error); 1684 } 1685 kernconfig_unlock(); 1686 1687 mutex_enter(&module_thread_lock); 1688 (void)cv_timedwait(&module_thread_cv, &module_thread_lock, 1689 module_thread_ticks); 1690 module_thread_ticks = 0; 1691 mutex_exit(&module_thread_lock); 1692 } 1693 } 1694 1695 /* 1696 * module_thread: 1697 * 1698 * Kick the module thread into action, perhaps because the 1699 * system is low on memory. 1700 */ 1701 void 1702 module_thread_kick(void) 1703 { 1704 1705 mutex_enter(&module_thread_lock); 1706 module_thread_ticks = hz; 1707 cv_broadcast(&module_thread_cv); 1708 mutex_exit(&module_thread_lock); 1709 } 1710 1711 #ifdef DDB 1712 /* 1713 * module_whatis: 1714 * 1715 * Helper routine for DDB. 1716 */ 1717 void 1718 module_whatis(uintptr_t addr, void (*pr)(const char *, ...)) 1719 { 1720 module_t *mod; 1721 size_t msize; 1722 vaddr_t maddr; 1723 1724 TAILQ_FOREACH(mod, &module_list, mod_chain) { 1725 if (mod->mod_kobj == NULL) { 1726 continue; 1727 } 1728 if (kobj_stat(mod->mod_kobj, &maddr, &msize) != 0) 1729 continue; 1730 if (addr < maddr || addr >= maddr + msize) { 1731 continue; 1732 } 1733 (*pr)("%p is %p+%zu, in kernel module `%s'\n", 1734 (void *)addr, (void *)maddr, 1735 (size_t)(addr - maddr), mod->mod_info->mi_name); 1736 } 1737 } 1738 1739 /* 1740 * module_print_list: 1741 * 1742 * Helper routine for DDB. 1743 */ 1744 void 1745 module_print_list(void (*pr)(const char *, ...)) 1746 { 1747 const char *src; 1748 module_t *mod; 1749 size_t msize; 1750 vaddr_t maddr; 1751 1752 (*pr)("%16s %16s %8s %8s\n", "NAME", "TEXT/DATA", "SIZE", "SOURCE"); 1753 1754 TAILQ_FOREACH(mod, &module_list, mod_chain) { 1755 switch (mod->mod_source) { 1756 case MODULE_SOURCE_KERNEL: 1757 src = "builtin"; 1758 break; 1759 case MODULE_SOURCE_FILESYS: 1760 src = "filesys"; 1761 break; 1762 case MODULE_SOURCE_BOOT: 1763 src = "boot"; 1764 break; 1765 default: 1766 src = "unknown"; 1767 break; 1768 } 1769 if (mod->mod_kobj == NULL) { 1770 maddr = 0; 1771 msize = 0; 1772 } else if (kobj_stat(mod->mod_kobj, &maddr, &msize) != 0) 1773 continue; 1774 (*pr)("%16s %16lx %8ld %8s\n", mod->mod_info->mi_name, 1775 (long)maddr, (long)msize, src); 1776 } 1777 } 1778 #endif /* DDB */ 1779 1780 static bool 1781 module_merge_dicts(prop_dictionary_t existing_dict, 1782 const prop_dictionary_t new_dict) 1783 { 1784 prop_dictionary_keysym_t props_keysym; 1785 prop_object_iterator_t props_iter; 1786 prop_object_t props_obj; 1787 const char *props_key; 1788 bool error; 1789 1790 if (new_dict == NULL) { /* nothing to merge */ 1791 return true; 1792 } 1793 1794 error = false; 1795 props_iter = prop_dictionary_iterator(new_dict); 1796 if (props_iter == NULL) { 1797 return false; 1798 } 1799 1800 while ((props_obj = prop_object_iterator_next(props_iter)) != NULL) { 1801 props_keysym = (prop_dictionary_keysym_t)props_obj; 1802 props_key = prop_dictionary_keysym_value(props_keysym); 1803 props_obj = prop_dictionary_get_keysym(new_dict, props_keysym); 1804 if ((props_obj == NULL) || !prop_dictionary_set(existing_dict, 1805 props_key, props_obj)) { 1806 error = true; 1807 goto out; 1808 } 1809 } 1810 error = false; 1811 1812 out: 1813 prop_object_iterator_release(props_iter); 1814 1815 return !error; 1816 } 1817 1818 /* 1819 * module_specific_key_create: 1820 * 1821 * Create a key for subsystem module-specific data. 1822 */ 1823 specificdata_key_t 1824 module_specific_key_create(specificdata_key_t *keyp, specificdata_dtor_t dtor) 1825 { 1826 1827 return specificdata_key_create(module_specificdata_domain, keyp, dtor); 1828 } 1829 1830 /* 1831 * module_specific_key_delete: 1832 * 1833 * Delete a key for subsystem module-specific data. 1834 */ 1835 void 1836 module_specific_key_delete(specificdata_key_t key) 1837 { 1838 1839 return specificdata_key_delete(module_specificdata_domain, key); 1840 } 1841 1842 /* 1843 * module_getspecific: 1844 * 1845 * Return module-specific data corresponding to the specified key. 1846 */ 1847 void * 1848 module_getspecific(module_t *mod, specificdata_key_t key) 1849 { 1850 1851 return specificdata_getspecific(module_specificdata_domain, 1852 &mod->mod_sdref, key); 1853 } 1854 1855 /* 1856 * module_setspecific: 1857 * 1858 * Set module-specific data corresponding to the specified key. 1859 */ 1860 void 1861 module_setspecific(module_t *mod, specificdata_key_t key, void *data) 1862 { 1863 1864 specificdata_setspecific(module_specificdata_domain, 1865 &mod->mod_sdref, key, data); 1866 } 1867 1868 /* 1869 * module_register_callbacks: 1870 * 1871 * Register a new set of callbacks to be called on module load/unload. 1872 * Call the load callback on each existing module. 1873 * Return an opaque handle for unregistering these later. 1874 */ 1875 void * 1876 module_register_callbacks(void (*load)(struct module *), 1877 void (*unload)(struct module *)) 1878 { 1879 struct module_callbacks *modcb; 1880 struct module *mod; 1881 1882 modcb = kmem_alloc(sizeof(*modcb), KM_SLEEP); 1883 modcb->modcb_load = load; 1884 modcb->modcb_unload = unload; 1885 1886 kernconfig_lock(); 1887 TAILQ_INSERT_TAIL(&modcblist, modcb, modcb_list); 1888 TAILQ_FOREACH(mod, &module_list, mod_chain) 1889 load(mod); 1890 kernconfig_unlock(); 1891 1892 return modcb; 1893 } 1894 1895 /* 1896 * module_unregister_callbacks: 1897 * 1898 * Unregister a previously-registered set of module load/unload callbacks. 1899 * Call the unload callback on each existing module. 1900 */ 1901 void 1902 module_unregister_callbacks(void *opaque) 1903 { 1904 struct module_callbacks *modcb; 1905 struct module *mod; 1906 1907 modcb = opaque; 1908 kernconfig_lock(); 1909 TAILQ_FOREACH(mod, &module_list, mod_chain) 1910 modcb->modcb_unload(mod); 1911 TAILQ_REMOVE(&modcblist, modcb, modcb_list); 1912 kernconfig_unlock(); 1913 kmem_free(modcb, sizeof(*modcb)); 1914 } 1915 1916 /* 1917 * module_callback_load: 1918 * 1919 * Helper routine: call all load callbacks on a module being loaded. 1920 */ 1921 static void 1922 module_callback_load(struct module *mod) 1923 { 1924 struct module_callbacks *modcb; 1925 1926 TAILQ_FOREACH(modcb, &modcblist, modcb_list) { 1927 modcb->modcb_load(mod); 1928 } 1929 } 1930 1931 /* 1932 * module_callback_unload: 1933 * 1934 * Helper routine: call all unload callbacks on a module being unloaded. 1935 */ 1936 static void 1937 module_callback_unload(struct module *mod) 1938 { 1939 struct module_callbacks *modcb; 1940 1941 TAILQ_FOREACH(modcb, &modcblist, modcb_list) { 1942 modcb->modcb_unload(mod); 1943 } 1944 } 1945