1 /*- 2 * Copyright (c) 1997 Doug Rabson 3 * All rights reserved. 4 * 5 * Redistribution and use in source and binary forms, with or without 6 * modification, are permitted provided that the following conditions 7 * are met: 8 * 1. Redistributions of source code must retain the above copyright 9 * notice, this list of conditions and the following disclaimer. 10 * 2. Redistributions in binary form must reproduce the above copyright 11 * notice, this list of conditions and the following disclaimer in the 12 * documentation and/or other materials provided with the distribution. 13 * 14 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 15 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 16 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 17 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 18 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 19 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 20 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 21 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 22 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 23 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 24 * SUCH DAMAGE. 25 */ 26 27 #include "opt_compat.h" 28 29 #include <sys/cdefs.h> 30 __FBSDID("$FreeBSD$"); 31 32 #include <sys/param.h> 33 #include <sys/kernel.h> 34 #include <sys/systm.h> 35 #include <sys/eventhandler.h> 36 #include <sys/malloc.h> 37 #include <sys/sysproto.h> 38 #include <sys/sysent.h> 39 #include <sys/proc.h> 40 #include <sys/lock.h> 41 #include <sys/mutex.h> 42 #include <sys/reboot.h> 43 #include <sys/sx.h> 44 #include <sys/module.h> 45 #include <sys/linker.h> 46 47 static MALLOC_DEFINE(M_MODULE, "module", "module data structures"); 48 49 typedef TAILQ_HEAD(, module) modulelist_t; 50 struct module { 51 TAILQ_ENTRY(module) link; /* chain together all modules */ 52 TAILQ_ENTRY(module) flink; /* all modules in a file */ 53 struct linker_file *file; /* file which contains this module */ 54 int refs; /* reference count */ 55 int id; /* unique id number */ 56 char *name; /* module name */ 57 modeventhand_t handler; /* event handler */ 58 void *arg; /* argument for handler */ 59 modspecific_t data; /* module specific data */ 60 }; 61 62 #define MOD_EVENT(mod, type) (mod)->handler((mod), (type), (mod)->arg) 63 64 static modulelist_t modules; 65 struct sx modules_sx; 66 static int nextid = 1; 67 static void module_shutdown(void *, int); 68 69 static int 70 modevent_nop(module_t mod, int what, void *arg) 71 { 72 73 switch(what) { 74 case MOD_LOAD: 75 return (0); 76 case MOD_UNLOAD: 77 return (EBUSY); 78 default: 79 return (EOPNOTSUPP); 80 } 81 } 82 83 static void 84 module_init(void *arg) 85 { 86 87 sx_init(&modules_sx, "module subsystem sx lock"); 88 TAILQ_INIT(&modules); 89 EVENTHANDLER_REGISTER(shutdown_final, module_shutdown, NULL, 90 SHUTDOWN_PRI_DEFAULT); 91 } 92 93 SYSINIT(module, SI_SUB_KLD, SI_ORDER_FIRST, module_init, 0) 94 95 static void 96 module_shutdown(void *arg1, int arg2) 97 { 98 module_t mod; 99 100 if (arg2 & RB_NOSYNC) 101 return; 102 mtx_lock(&Giant); 103 MOD_SLOCK; 104 TAILQ_FOREACH(mod, &modules, link) 105 MOD_EVENT(mod, MOD_SHUTDOWN); 106 MOD_SUNLOCK; 107 mtx_unlock(&Giant); 108 } 109 110 void 111 module_register_init(const void *arg) 112 { 113 const moduledata_t *data = (const moduledata_t *)arg; 114 int error; 115 module_t mod; 116 117 mtx_lock(&Giant); 118 MOD_SLOCK; 119 mod = module_lookupbyname(data->name); 120 if (mod == NULL) 121 panic("module_register_init: module named %s not found\n", 122 data->name); 123 MOD_SUNLOCK; 124 error = MOD_EVENT(mod, MOD_LOAD); 125 if (error) { 126 MOD_EVENT(mod, MOD_UNLOAD); 127 MOD_XLOCK; 128 module_release(mod); 129 MOD_XUNLOCK; 130 printf("module_register_init: MOD_LOAD (%s, %p, %p) error" 131 " %d\n", data->name, (void *)data->evhand, data->priv, 132 error); 133 } 134 mtx_unlock(&Giant); 135 } 136 137 int 138 module_register(const moduledata_t *data, linker_file_t container) 139 { 140 size_t namelen; 141 module_t newmod; 142 143 MOD_XLOCK; 144 newmod = module_lookupbyname(data->name); 145 if (newmod != NULL) { 146 MOD_XUNLOCK; 147 printf("module_register: module %s already exists!\n", 148 data->name); 149 return (EEXIST); 150 } 151 namelen = strlen(data->name) + 1; 152 newmod = malloc(sizeof(struct module) + namelen, M_MODULE, M_WAITOK); 153 if (newmod == NULL) { 154 MOD_XUNLOCK; 155 return (ENOMEM); 156 } 157 newmod->refs = 1; 158 newmod->id = nextid++; 159 newmod->name = (char *)(newmod + 1); 160 strcpy(newmod->name, data->name); 161 newmod->handler = data->evhand ? data->evhand : modevent_nop; 162 newmod->arg = data->priv; 163 bzero(&newmod->data, sizeof(newmod->data)); 164 TAILQ_INSERT_TAIL(&modules, newmod, link); 165 166 if (container) 167 TAILQ_INSERT_TAIL(&container->modules, newmod, flink); 168 newmod->file = container; 169 MOD_XUNLOCK; 170 return (0); 171 } 172 173 void 174 module_reference(module_t mod) 175 { 176 177 MOD_XLOCK_ASSERT; 178 179 MOD_DPF(REFS, ("module_reference: before, refs=%d\n", mod->refs)); 180 mod->refs++; 181 } 182 183 void 184 module_release(module_t mod) 185 { 186 187 MOD_XLOCK_ASSERT; 188 189 if (mod->refs <= 0) 190 panic("module_release: bad reference count"); 191 192 MOD_DPF(REFS, ("module_release: before, refs=%d\n", mod->refs)); 193 194 mod->refs--; 195 if (mod->refs == 0) { 196 TAILQ_REMOVE(&modules, mod, link); 197 if (mod->file) 198 TAILQ_REMOVE(&mod->file->modules, mod, flink); 199 MOD_XUNLOCK; 200 free(mod, M_MODULE); 201 MOD_XLOCK; 202 } 203 } 204 205 module_t 206 module_lookupbyname(const char *name) 207 { 208 module_t mod; 209 int err; 210 211 MOD_LOCK_ASSERT; 212 213 TAILQ_FOREACH(mod, &modules, link) { 214 err = strcmp(mod->name, name); 215 if (err == 0) 216 return (mod); 217 } 218 return (NULL); 219 } 220 221 module_t 222 module_lookupbyid(int modid) 223 { 224 module_t mod; 225 226 MOD_LOCK_ASSERT; 227 228 TAILQ_FOREACH(mod, &modules, link) 229 if (mod->id == modid) 230 return(mod); 231 return (NULL); 232 } 233 234 int 235 module_unload(module_t mod, int flags) 236 { 237 int error; 238 239 mtx_lock(&Giant); 240 error = MOD_EVENT(mod, MOD_QUIESCE); 241 if (error == EOPNOTSUPP || error == EINVAL) 242 error = 0; 243 if (error == 0 || flags == LINKER_UNLOAD_FORCE) 244 error = MOD_EVENT(mod, MOD_UNLOAD); 245 mtx_unlock(&Giant); 246 return (error); 247 } 248 249 int 250 module_getid(module_t mod) 251 { 252 253 MOD_LOCK_ASSERT; 254 return (mod->id); 255 } 256 257 module_t 258 module_getfnext(module_t mod) 259 { 260 261 MOD_LOCK_ASSERT; 262 return (TAILQ_NEXT(mod, flink)); 263 } 264 265 void 266 module_setspecific(module_t mod, modspecific_t *datap) 267 { 268 269 MOD_XLOCK_ASSERT; 270 mod->data = *datap; 271 } 272 273 linker_file_t 274 module_file(module_t mod) 275 { 276 277 return (mod->file); 278 } 279 280 /* 281 * Syscalls. 282 */ 283 /* 284 * MPSAFE 285 */ 286 int 287 modnext(struct thread *td, struct modnext_args *uap) 288 { 289 module_t mod; 290 int error = 0; 291 292 td->td_retval[0] = -1; 293 294 MOD_SLOCK; 295 if (uap->modid == 0) { 296 mod = TAILQ_FIRST(&modules); 297 if (mod) 298 td->td_retval[0] = mod->id; 299 else 300 error = ENOENT; 301 goto done2; 302 } 303 mod = module_lookupbyid(uap->modid); 304 if (mod == NULL) { 305 error = ENOENT; 306 goto done2; 307 } 308 if (TAILQ_NEXT(mod, link)) 309 td->td_retval[0] = TAILQ_NEXT(mod, link)->id; 310 else 311 td->td_retval[0] = 0; 312 done2: 313 MOD_SUNLOCK; 314 return (error); 315 } 316 317 /* 318 * MPSAFE 319 */ 320 int 321 modfnext(struct thread *td, struct modfnext_args *uap) 322 { 323 module_t mod; 324 int error; 325 326 td->td_retval[0] = -1; 327 328 MOD_SLOCK; 329 mod = module_lookupbyid(uap->modid); 330 if (mod == NULL) { 331 error = ENOENT; 332 } else { 333 error = 0; 334 if (TAILQ_NEXT(mod, flink)) 335 td->td_retval[0] = TAILQ_NEXT(mod, flink)->id; 336 else 337 td->td_retval[0] = 0; 338 } 339 MOD_SUNLOCK; 340 return (error); 341 } 342 343 struct module_stat_v1 { 344 int version; /* set to sizeof(struct module_stat) */ 345 char name[MAXMODNAME]; 346 int refs; 347 int id; 348 }; 349 350 /* 351 * MPSAFE 352 */ 353 int 354 modstat(struct thread *td, struct modstat_args *uap) 355 { 356 module_t mod; 357 modspecific_t data; 358 int error = 0; 359 int id, namelen, refs, version; 360 struct module_stat *stat; 361 char *name; 362 363 MOD_SLOCK; 364 mod = module_lookupbyid(uap->modid); 365 if (mod == NULL) { 366 MOD_SUNLOCK; 367 return (ENOENT); 368 } 369 id = mod->id; 370 refs = mod->refs; 371 name = mod->name; 372 data = mod->data; 373 MOD_SUNLOCK; 374 stat = uap->stat; 375 376 /* 377 * Check the version of the user's structure. 378 */ 379 if ((error = copyin(&stat->version, &version, sizeof(version))) != 0) 380 return (error); 381 if (version != sizeof(struct module_stat_v1) 382 && version != sizeof(struct module_stat)) 383 return (EINVAL); 384 namelen = strlen(mod->name) + 1; 385 if (namelen > MAXMODNAME) 386 namelen = MAXMODNAME; 387 if ((error = copyout(name, &stat->name[0], namelen)) != 0) 388 return (error); 389 390 if ((error = copyout(&refs, &stat->refs, sizeof(int))) != 0) 391 return (error); 392 if ((error = copyout(&id, &stat->id, sizeof(int))) != 0) 393 return (error); 394 395 /* 396 * >v1 stat includes module data. 397 */ 398 if (version == sizeof(struct module_stat)) 399 if ((error = copyout(&data, &stat->data, 400 sizeof(data))) != 0) 401 return (error); 402 td->td_retval[0] = 0; 403 return (error); 404 } 405 406 /* 407 * MPSAFE 408 */ 409 int 410 modfind(struct thread *td, struct modfind_args *uap) 411 { 412 int error = 0; 413 char name[MAXMODNAME]; 414 module_t mod; 415 416 if ((error = copyinstr(uap->name, name, sizeof name, 0)) != 0) 417 return (error); 418 419 MOD_SLOCK; 420 mod = module_lookupbyname(name); 421 if (mod == NULL) 422 error = ENOENT; 423 else 424 td->td_retval[0] = module_getid(mod); 425 MOD_SUNLOCK; 426 return (error); 427 } 428 429 #ifdef COMPAT_IA32 430 #include <sys/mount.h> 431 #include <compat/freebsd32/freebsd32_util.h> 432 #include <compat/freebsd32/freebsd32.h> 433 #include <compat/freebsd32/freebsd32_proto.h> 434 435 typedef union modspecific32 { 436 int intval; 437 u_int32_t uintval; 438 int longval; 439 u_int32_t ulongval; 440 } modspecific32_t; 441 442 struct module_stat32 { 443 int version; 444 char name[MAXMODNAME]; 445 int refs; 446 int id; 447 modspecific32_t data; 448 }; 449 450 /* 451 * MPSAFE 452 */ 453 int 454 freebsd32_modstat(struct thread *td, struct freebsd32_modstat_args *uap) 455 { 456 module_t mod; 457 modspecific32_t data32; 458 int error = 0; 459 int id, namelen, refs, version; 460 struct module_stat32 *stat32; 461 char *name; 462 463 MOD_SLOCK; 464 mod = module_lookupbyid(uap->modid); 465 if (mod == NULL) { 466 MOD_SUNLOCK; 467 return (ENOENT); 468 } 469 470 id = mod->id; 471 refs = mod->refs; 472 name = mod->name; 473 CP(mod->data, data32, intval); 474 CP(mod->data, data32, uintval); 475 CP(mod->data, data32, longval); 476 CP(mod->data, data32, ulongval); 477 MOD_SUNLOCK; 478 stat32 = uap->stat; 479 480 if ((error = copyin(&stat32->version, &version, sizeof(version))) != 0) 481 return (error); 482 if (version != sizeof(struct module_stat_v1) 483 && version != sizeof(struct module_stat32)) 484 return (EINVAL); 485 namelen = strlen(mod->name) + 1; 486 if (namelen > MAXMODNAME) 487 namelen = MAXMODNAME; 488 if ((error = copyout(name, &stat32->name[0], namelen)) != 0) 489 return (error); 490 491 if ((error = copyout(&refs, &stat32->refs, sizeof(int))) != 0) 492 return (error); 493 if ((error = copyout(&id, &stat32->id, sizeof(int))) != 0) 494 return (error); 495 496 /* 497 * >v1 stat includes module data. 498 */ 499 if (version == sizeof(struct module_stat32)) 500 if ((error = copyout(&data32, &stat32->data, 501 sizeof(data32))) != 0) 502 return (error); 503 td->td_retval[0] = 0; 504 return (error); 505 } 506 #endif 507