| 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 | * $FreeBSD: src/sys/kern/kern_module.c,v 1.21 1999/11/08 06:53:30 peter Exp $ |
| 27 | */ |
| 28 | |
| 29 | #include <sys/param.h> |
| 30 | #include <sys/kernel.h> |
| 31 | #include <sys/systm.h> |
| 32 | #include <sys/eventhandler.h> |
| 33 | #include <sys/malloc.h> |
| 34 | #include <sys/sysmsg.h> |
| 35 | #include <sys/sysent.h> |
| 36 | #include <sys/module.h> |
| 37 | #include <sys/linker.h> |
| 38 | #include <sys/proc.h> |
| 39 | |
| 40 | MALLOC_DEFINE(M_MODULE, "module", "module data structures"); |
| 41 | |
| 42 | typedef TAILQ_HEAD(, module) modulelist_t; |
| 43 | struct module { |
| 44 | TAILQ_ENTRY(module) link; /* chain together all modules */ |
| 45 | TAILQ_ENTRY(module) flink; /* all modules in a file */ |
| 46 | struct linker_file* file; /* file which contains this module */ |
| 47 | int refs; /* reference count */ |
| 48 | int id; /* unique id number */ |
| 49 | char *name; /* module name */ |
| 50 | modeventhand_t handler; /* event handler */ |
| 51 | void *arg; /* argument for handler */ |
| 52 | modspecific_t data; /* module specific data */ |
| 53 | }; |
| 54 | |
| 55 | #define MOD_EVENT(mod, type) (mod)->handler((mod), (type), (mod)->arg) |
| 56 | |
| 57 | static modulelist_t modules = TAILQ_HEAD_INITIALIZER(modules); |
| 58 | static struct lwkt_token mod_token = LWKT_TOKEN_INITIALIZER(mod_token); |
| 59 | static int nextid = 1; |
| 60 | |
| 61 | static void module_shutdown(void*, int); |
| 62 | |
| 63 | static int |
| 64 | modevent_nop(module_t mod, int what, void* arg) |
| 65 | { |
| 66 | return 0; |
| 67 | } |
| 68 | |
| 69 | |
| 70 | static void |
| 71 | module_init(void* arg) |
| 72 | { |
| 73 | TAILQ_INIT(&modules); |
| 74 | EVENTHANDLER_REGISTER(shutdown_post_sync, module_shutdown, NULL, |
| 75 | SHUTDOWN_PRI_DEFAULT); |
| 76 | } |
| 77 | |
| 78 | SYSINIT(module, SI_BOOT2_KLD, SI_ORDER_FIRST, module_init, 0); |
| 79 | |
| 80 | static void |
| 81 | module_shutdown(void* arg1, int arg2) |
| 82 | { |
| 83 | module_t mod; |
| 84 | |
| 85 | for (mod = TAILQ_FIRST(&modules); mod; mod = TAILQ_NEXT(mod, link)) |
| 86 | MOD_EVENT(mod, MOD_SHUTDOWN); |
| 87 | } |
| 88 | |
| 89 | void |
| 90 | module_register_init(const void *arg) |
| 91 | { |
| 92 | const moduledata_t* data = (const moduledata_t*) arg; |
| 93 | int error; |
| 94 | module_t mod; |
| 95 | |
| 96 | mod = module_lookupbyname(data->name); |
| 97 | if (mod == NULL) { |
| 98 | #if 0 |
| 99 | panic("module_register_init: module named %s not found", data->name); |
| 100 | #else |
| 101 | /* temporary kludge until kernel `file' attachment registers modules */ |
| 102 | error = module_register(data, linker_kernel_file); |
| 103 | if (error) |
| 104 | panic("module_register_init: register of module failed! %d", error); |
| 105 | mod = module_lookupbyname(data->name); |
| 106 | if (mod == NULL) |
| 107 | panic("module_register_init: module STILL not found!"); |
| 108 | #endif |
| 109 | } |
| 110 | error = MOD_EVENT(mod, MOD_LOAD); |
| 111 | if (error) { |
| 112 | module_unload(mod); /* ignore error */ |
| 113 | module_release(mod); |
| 114 | kprintf("module_register_init: MOD_LOAD (%s, %lx, %p) error %d\n", |
| 115 | data->name, (u_long)data->evhand, data->priv, error); |
| 116 | } |
| 117 | } |
| 118 | |
| 119 | int |
| 120 | module_register(const moduledata_t *data, linker_file_t container) |
| 121 | { |
| 122 | size_t namelen; |
| 123 | module_t newmod; |
| 124 | |
| 125 | newmod = module_lookupbyname(data->name); |
| 126 | if (newmod != NULL) { |
| 127 | kprintf("module_register: module %s already exists!\n", data->name); |
| 128 | return EEXIST; |
| 129 | } |
| 130 | namelen = strlen(data->name) + 1; |
| 131 | newmod = (module_t) kmalloc(sizeof(struct module) + namelen, |
| 132 | M_MODULE, M_WAITOK); |
| 133 | |
| 134 | newmod->refs = 1; |
| 135 | newmod->id = nextid++; |
| 136 | newmod->name = (char *) (newmod + 1); |
| 137 | strcpy(newmod->name, data->name); |
| 138 | newmod->handler = data->evhand ? data->evhand : modevent_nop; |
| 139 | newmod->arg = data->priv; |
| 140 | bzero(&newmod->data, sizeof(newmod->data)); |
| 141 | TAILQ_INSERT_TAIL(&modules, newmod, link); |
| 142 | |
| 143 | if (container == NULL) |
| 144 | container = linker_current_file; |
| 145 | if (container) |
| 146 | TAILQ_INSERT_TAIL(&container->modules, newmod, flink); |
| 147 | newmod->file = container; |
| 148 | |
| 149 | return 0; |
| 150 | } |
| 151 | |
| 152 | void |
| 153 | module_reference(module_t mod) |
| 154 | { |
| 155 | MOD_DPF(REFS, ("module_reference: before, refs=%d\n", mod->refs)); |
| 156 | |
| 157 | mod->refs++; |
| 158 | } |
| 159 | |
| 160 | /* |
| 161 | * module_release() |
| 162 | * |
| 163 | * Release ref on the module and return the new reference count. If 0 |
| 164 | * is returned, the module has been removed from its list and freed. |
| 165 | */ |
| 166 | int |
| 167 | module_release(module_t mod) |
| 168 | { |
| 169 | int rc; |
| 170 | |
| 171 | if (mod->refs <= 0) |
| 172 | panic("module_release: bad reference count"); |
| 173 | |
| 174 | MOD_DPF(REFS, ("module_release: before, refs=%d\n", mod->refs)); |
| 175 | |
| 176 | rc = --mod->refs; |
| 177 | if (rc == 0) { |
| 178 | TAILQ_REMOVE(&modules, mod, link); |
| 179 | if (mod->file) { |
| 180 | TAILQ_REMOVE(&mod->file->modules, mod, flink); |
| 181 | } |
| 182 | kfree(mod, M_MODULE); |
| 183 | } |
| 184 | return(rc); |
| 185 | } |
| 186 | |
| 187 | module_t |
| 188 | module_lookupbyname(const char* name) |
| 189 | { |
| 190 | module_t mod; |
| 191 | |
| 192 | for (mod = TAILQ_FIRST(&modules); mod; mod = TAILQ_NEXT(mod, link)) { |
| 193 | if (!strcmp(mod->name, name)) |
| 194 | return mod; |
| 195 | } |
| 196 | |
| 197 | return NULL; |
| 198 | } |
| 199 | |
| 200 | module_t |
| 201 | module_lookupbyid(int modid) |
| 202 | { |
| 203 | module_t mod; |
| 204 | |
| 205 | for (mod = TAILQ_FIRST(&modules); mod; mod = TAILQ_NEXT(mod, link)) { |
| 206 | if (mod->id == modid) |
| 207 | return mod; |
| 208 | } |
| 209 | |
| 210 | return NULL; |
| 211 | } |
| 212 | |
| 213 | int |
| 214 | module_unload(module_t mod) |
| 215 | { |
| 216 | int error; |
| 217 | |
| 218 | error = MOD_EVENT(mod, MOD_UNLOAD); |
| 219 | /*sync_devs();*/ |
| 220 | return (error); |
| 221 | } |
| 222 | |
| 223 | int |
| 224 | module_getid(module_t mod) |
| 225 | { |
| 226 | return mod->id; |
| 227 | } |
| 228 | |
| 229 | module_t |
| 230 | module_getfnext(module_t mod) |
| 231 | { |
| 232 | return TAILQ_NEXT(mod, flink); |
| 233 | } |
| 234 | |
| 235 | void |
| 236 | module_setspecific(module_t mod, modspecific_t *datap) |
| 237 | { |
| 238 | mod->data = *datap; |
| 239 | } |
| 240 | |
| 241 | /* |
| 242 | * Syscalls. |
| 243 | * |
| 244 | * MPALMOSTSAFE |
| 245 | */ |
| 246 | int |
| 247 | sys_modnext(struct sysmsg *sysmsg, const struct modnext_args *uap) |
| 248 | { |
| 249 | module_t mod; |
| 250 | int error; |
| 251 | |
| 252 | error = 0; |
| 253 | lwkt_gettoken(&mod_token); |
| 254 | sysmsg->sysmsg_result = -1; |
| 255 | if (uap->modid == 0) { |
| 256 | mod = TAILQ_FIRST(&modules); |
| 257 | if (mod) |
| 258 | sysmsg->sysmsg_result = mod->id; |
| 259 | else |
| 260 | error = ENOENT; |
| 261 | goto done; |
| 262 | } |
| 263 | |
| 264 | mod = module_lookupbyid(uap->modid); |
| 265 | if (!mod) { |
| 266 | error = ENOENT; |
| 267 | goto done; |
| 268 | } |
| 269 | |
| 270 | if (TAILQ_NEXT(mod, link)) |
| 271 | sysmsg->sysmsg_result = TAILQ_NEXT(mod, link)->id; |
| 272 | else |
| 273 | sysmsg->sysmsg_result = 0; |
| 274 | done: |
| 275 | lwkt_reltoken(&mod_token); |
| 276 | |
| 277 | return error; |
| 278 | } |
| 279 | |
| 280 | /* |
| 281 | * MPALMOSTSAFE |
| 282 | */ |
| 283 | int |
| 284 | sys_modfnext(struct sysmsg *sysmsg, const struct modfnext_args *uap) |
| 285 | { |
| 286 | module_t mod; |
| 287 | int error; |
| 288 | |
| 289 | lwkt_gettoken(&mod_token); |
| 290 | sysmsg->sysmsg_result = -1; |
| 291 | |
| 292 | mod = module_lookupbyid(uap->modid); |
| 293 | if (!mod) { |
| 294 | error = ENOENT; |
| 295 | goto done; |
| 296 | } |
| 297 | |
| 298 | if (TAILQ_NEXT(mod, flink)) |
| 299 | sysmsg->sysmsg_result = TAILQ_NEXT(mod, flink)->id; |
| 300 | else |
| 301 | sysmsg->sysmsg_result = 0; |
| 302 | error = 0; |
| 303 | done: |
| 304 | lwkt_reltoken(&mod_token); |
| 305 | |
| 306 | return error; |
| 307 | } |
| 308 | |
| 309 | struct module_stat_v1 { |
| 310 | int version; /* set to sizeof(struct module_stat) */ |
| 311 | char name[MAXMODNAME]; |
| 312 | int refs; |
| 313 | int id; |
| 314 | }; |
| 315 | |
| 316 | /* |
| 317 | * MPALMOSTSAFE |
| 318 | */ |
| 319 | int |
| 320 | sys_modstat(struct sysmsg *sysmsg, const struct modstat_args *uap) |
| 321 | { |
| 322 | module_t mod; |
| 323 | int error; |
| 324 | int namelen; |
| 325 | int version; |
| 326 | struct module_stat* stat; |
| 327 | |
| 328 | lwkt_gettoken(&mod_token); |
| 329 | mod = module_lookupbyid(uap->modid); |
| 330 | if (!mod) { |
| 331 | error = ENOENT; |
| 332 | goto out; |
| 333 | } |
| 334 | |
| 335 | stat = uap->stat; |
| 336 | |
| 337 | /* |
| 338 | * Check the version of the user's structure. |
| 339 | */ |
| 340 | if ((error = copyin(&stat->version, &version, sizeof(version))) != 0) |
| 341 | goto out; |
| 342 | if (version != sizeof(struct module_stat_v1) |
| 343 | && version != sizeof(struct module_stat)) { |
| 344 | error = EINVAL; |
| 345 | goto out; |
| 346 | } |
| 347 | |
| 348 | namelen = strlen(mod->name) + 1; |
| 349 | if (namelen > MAXMODNAME) |
| 350 | namelen = MAXMODNAME; |
| 351 | if ((error = copyout(mod->name, &stat->name[0], namelen)) != 0) |
| 352 | goto out; |
| 353 | |
| 354 | if ((error = copyout(&mod->refs, &stat->refs, sizeof(int))) != 0) |
| 355 | goto out; |
| 356 | if ((error = copyout(&mod->id, &stat->id, sizeof(int))) != 0) |
| 357 | goto out; |
| 358 | |
| 359 | /* |
| 360 | * >v1 stat includes module data. |
| 361 | */ |
| 362 | if (version == sizeof(struct module_stat)) { |
| 363 | if ((error = copyout(&mod->data, &stat->data, sizeof(mod->data))) != 0) |
| 364 | goto out; |
| 365 | } |
| 366 | |
| 367 | sysmsg->sysmsg_result = 0; |
| 368 | |
| 369 | out: |
| 370 | lwkt_reltoken(&mod_token); |
| 371 | |
| 372 | return error; |
| 373 | } |
| 374 | |
| 375 | /* |
| 376 | * MPALMOSTSAFE |
| 377 | */ |
| 378 | int |
| 379 | sys_modfind(struct sysmsg *sysmsg, const struct modfind_args *uap) |
| 380 | { |
| 381 | int error; |
| 382 | char name[MAXMODNAME]; |
| 383 | module_t mod; |
| 384 | |
| 385 | lwkt_gettoken(&mod_token); |
| 386 | if ((error = copyinstr(uap->name, name, sizeof name, 0)) != 0) |
| 387 | goto out; |
| 388 | |
| 389 | mod = module_lookupbyname(name); |
| 390 | if (!mod) |
| 391 | error = ENOENT; |
| 392 | else |
| 393 | sysmsg->sysmsg_result = mod->id; |
| 394 | |
| 395 | out: |
| 396 | lwkt_reltoken(&mod_token); |
| 397 | |
| 398 | return error; |
| 399 | } |