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 MOD_SLOCK; 103 TAILQ_FOREACH(mod, &modules, link) 104 MOD_EVENT(mod, MOD_SHUTDOWN); 105 MOD_SUNLOCK; 106 } 107 108 void 109 module_register_init(const void *arg) 110 { 111 const moduledata_t *data = (const moduledata_t *)arg; 112 int error; 113 module_t mod; 114 115 MOD_SLOCK; 116 mod = module_lookupbyname(data->name); 117 if (mod == NULL) 118 panic("module_register_init: module named %s not found\n", 119 data->name); 120 MOD_SUNLOCK; 121 error = MOD_EVENT(mod, MOD_LOAD); 122 if (error) { 123 MOD_EVENT(mod, MOD_UNLOAD); 124 MOD_XLOCK; 125 module_release(mod); 126 MOD_XUNLOCK; 127 printf("module_register_init: MOD_LOAD (%s, %p, %p) error" 128 " %d\n", data->name, (void *)data->evhand, data->priv, 129 error); 130 } 131 } 132 133 int 134 module_register(const moduledata_t *data, linker_file_t container) 135 { 136 size_t namelen; 137 module_t newmod; 138 139 MOD_SLOCK; 140 newmod = module_lookupbyname(data->name); 141 if (newmod != NULL) { 142 MOD_SUNLOCK; 143 printf("module_register: module %s already exists!\n", 144 data->name); 145 return (EEXIST); 146 } 147 MOD_SUNLOCK; 148 namelen = strlen(data->name) + 1; 149 newmod = malloc(sizeof(struct module) + namelen, M_MODULE, M_WAITOK); 150 if (newmod == NULL) 151 return (ENOMEM); 152 MOD_XLOCK; 153 newmod->refs = 1; 154 newmod->id = nextid++; 155 newmod->name = (char *)(newmod + 1); 156 strcpy(newmod->name, data->name); 157 newmod->handler = data->evhand ? data->evhand : modevent_nop; 158 newmod->arg = data->priv; 159 bzero(&newmod->data, sizeof(newmod->data)); 160 TAILQ_INSERT_TAIL(&modules, newmod, link); 161 162 if (container) 163 TAILQ_INSERT_TAIL(&container->modules, newmod, flink); 164 newmod->file = container; 165 MOD_XUNLOCK; 166 return (0); 167 } 168 169 void 170 module_reference(module_t mod) 171 { 172 173 MOD_XLOCK_ASSERT; 174 175 MOD_DPF(REFS, ("module_reference: before, refs=%d\n", mod->refs)); 176 mod->refs++; 177 } 178 179 void 180 module_release(module_t mod) 181 { 182 183 MOD_XLOCK_ASSERT; 184 185 if (mod->refs <= 0) 186 panic("module_release: bad reference count"); 187 188 MOD_DPF(REFS, ("module_release: before, refs=%d\n", mod->refs)); 189 190 mod->refs--; 191 if (mod->refs == 0) { 192 TAILQ_REMOVE(&modules, mod, link); 193 if (mod->file) 194 TAILQ_REMOVE(&mod->file->modules, mod, flink); 195 MOD_XUNLOCK; 196 free(mod, M_MODULE); 197 MOD_XLOCK; 198 } 199 } 200 201 module_t 202 module_lookupbyname(const char *name) 203 { 204 module_t mod; 205 int err; 206 207 MOD_LOCK_ASSERT; 208 209 TAILQ_FOREACH(mod, &modules, link) { 210 err = strcmp(mod->name, name); 211 if (err == 0) 212 return (mod); 213 } 214 return (NULL); 215 } 216 217 module_t 218 module_lookupbyid(int modid) 219 { 220 module_t mod; 221 222 MOD_LOCK_ASSERT; 223 224 TAILQ_FOREACH(mod, &modules, link) 225 if (mod->id == modid) 226 return(mod); 227 return (NULL); 228 } 229 230 int 231 module_unload(module_t mod, int flags) 232 { 233 int error; 234 235 error = MOD_EVENT(mod, MOD_QUIESCE); 236 if (error == EOPNOTSUPP || error == EINVAL) 237 error = 0; 238 if (flags == LINKER_UNLOAD_NORMAL && error != 0) 239 return (error); 240 return (MOD_EVENT(mod, MOD_UNLOAD)); 241 } 242 243 int 244 module_getid(module_t mod) 245 { 246 247 MOD_LOCK_ASSERT; 248 return (mod->id); 249 } 250 251 module_t 252 module_getfnext(module_t mod) 253 { 254 255 MOD_LOCK_ASSERT; 256 return (TAILQ_NEXT(mod, flink)); 257 } 258 259 void 260 module_setspecific(module_t mod, modspecific_t *datap) 261 { 262 263 MOD_XLOCK_ASSERT; 264 mod->data = *datap; 265 } 266 267 /* 268 * Syscalls. 269 */ 270 /* 271 * MPSAFE 272 */ 273 int 274 modnext(struct thread *td, struct modnext_args *uap) 275 { 276 module_t mod; 277 int error = 0; 278 279 td->td_retval[0] = -1; 280 281 MOD_SLOCK; 282 if (uap->modid == 0) { 283 mod = TAILQ_FIRST(&modules); 284 if (mod) 285 td->td_retval[0] = mod->id; 286 else 287 error = ENOENT; 288 goto done2; 289 } 290 mod = module_lookupbyid(uap->modid); 291 if (mod == NULL) { 292 error = ENOENT; 293 goto done2; 294 } 295 if (TAILQ_NEXT(mod, link)) 296 td->td_retval[0] = TAILQ_NEXT(mod, link)->id; 297 else 298 td->td_retval[0] = 0; 299 done2: 300 MOD_SUNLOCK; 301 return (error); 302 } 303 304 /* 305 * MPSAFE 306 */ 307 int 308 modfnext(struct thread *td, struct modfnext_args *uap) 309 { 310 module_t mod; 311 int error; 312 313 td->td_retval[0] = -1; 314 315 MOD_SLOCK; 316 mod = module_lookupbyid(uap->modid); 317 if (mod == NULL) { 318 error = ENOENT; 319 } else { 320 error = 0; 321 if (TAILQ_NEXT(mod, flink)) 322 td->td_retval[0] = TAILQ_NEXT(mod, flink)->id; 323 else 324 td->td_retval[0] = 0; 325 } 326 MOD_SUNLOCK; 327 return (error); 328 } 329 330 struct module_stat_v1 { 331 int version; /* set to sizeof(struct module_stat) */ 332 char name[MAXMODNAME]; 333 int refs; 334 int id; 335 }; 336 337 /* 338 * MPSAFE 339 */ 340 int 341 modstat(struct thread *td, struct modstat_args *uap) 342 { 343 module_t mod; 344 modspecific_t data; 345 int error = 0; 346 int id, namelen, refs, version; 347 struct module_stat *stat; 348 char *name; 349 350 MOD_SLOCK; 351 mod = module_lookupbyid(uap->modid); 352 if (mod == NULL) { 353 MOD_SUNLOCK; 354 return (ENOENT); 355 } 356 id = mod->id; 357 refs = mod->refs; 358 name = mod->name; 359 data = mod->data; 360 MOD_SUNLOCK; 361 stat = uap->stat; 362 363 /* 364 * Check the version of the user's structure. 365 */ 366 if ((error = copyin(&stat->version, &version, sizeof(version))) != 0) 367 return (error); 368 if (version != sizeof(struct module_stat_v1) 369 && version != sizeof(struct module_stat)) 370 return (EINVAL); 371 namelen = strlen(mod->name) + 1; 372 if (namelen > MAXMODNAME) 373 namelen = MAXMODNAME; 374 if ((error = copyout(name, &stat->name[0], namelen)) != 0) 375 return (error); 376 377 if ((error = copyout(&refs, &stat->refs, sizeof(int))) != 0) 378 return (error); 379 if ((error = copyout(&id, &stat->id, sizeof(int))) != 0) 380 return (error); 381 382 /* 383 * >v1 stat includes module data. 384 */ 385 if (version == sizeof(struct module_stat)) 386 if ((error = copyout(&data, &stat->data, 387 sizeof(data))) != 0) 388 return (error); 389 td->td_retval[0] = 0; 390 return (error); 391 } 392 393 /* 394 * MPSAFE 395 */ 396 int 397 modfind(struct thread *td, struct modfind_args *uap) 398 { 399 int error = 0; 400 char name[MAXMODNAME]; 401 module_t mod; 402 403 if ((error = copyinstr(uap->name, name, sizeof name, 0)) != 0) 404 return (error); 405 406 MOD_SLOCK; 407 mod = module_lookupbyname(name); 408 if (mod == NULL) 409 error = ENOENT; 410 else 411 td->td_retval[0] = module_getid(mod); 412 MOD_SUNLOCK; 413 return (error); 414 } 415 416 #ifdef COMPAT_IA32 417 #include <sys/mount.h> 418 #include <compat/freebsd32/freebsd32_util.h> 419 #include <compat/freebsd32/freebsd32.h> 420 #include <compat/freebsd32/freebsd32_proto.h> 421 422 typedef union modspecific32 { 423 int intval; 424 u_int32_t uintval; 425 int longval; 426 u_int32_t ulongval; 427 } modspecific32_t; 428 429 struct module_stat32 { 430 int version; 431 char name[MAXMODNAME]; 432 int refs; 433 int id; 434 modspecific32_t data; 435 }; 436 437 /* 438 * MPSAFE 439 */ 440 int 441 freebsd32_modstat(struct thread *td, struct freebsd32_modstat_args *uap) 442 { 443 module_t mod; 444 modspecific32_t data32; 445 int error = 0; 446 int id, namelen, refs, version; 447 struct module_stat32 *stat32; 448 char *name; 449 450 MOD_SLOCK; 451 mod = module_lookupbyid(uap->modid); 452 if (mod == NULL) { 453 MOD_SUNLOCK; 454 return (ENOENT); 455 } 456 457 id = mod->id; 458 refs = mod->refs; 459 name = mod->name; 460 CP(mod->data, data32, intval); 461 CP(mod->data, data32, uintval); 462 CP(mod->data, data32, longval); 463 CP(mod->data, data32, ulongval); 464 MOD_SUNLOCK; 465 stat32 = uap->stat; 466 467 if ((error = copyin(&stat32->version, &version, sizeof(version))) != 0) 468 return (error); 469 if (version != sizeof(struct module_stat_v1) 470 && version != sizeof(struct module_stat32)) 471 return (EINVAL); 472 namelen = strlen(mod->name) + 1; 473 if (namelen > MAXMODNAME) 474 namelen = MAXMODNAME; 475 if ((error = copyout(name, &stat32->name[0], namelen)) != 0) 476 return (error); 477 478 if ((error = copyout(&refs, &stat32->refs, sizeof(int))) != 0) 479 return (error); 480 if ((error = copyout(&id, &stat32->id, sizeof(int))) != 0) 481 return (error); 482 483 /* 484 * >v1 stat includes module data. 485 */ 486 if (version == sizeof(struct module_stat32)) 487 if ((error = copyout(&data32, &stat32->data, 488 sizeof(data32))) != 0) 489 return (error); 490 td->td_retval[0] = 0; 491 return (error); 492 } 493 #endif 494