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/sysproto.h> 35 #include <sys/sysent.h> 36 #include <sys/module.h> 37 #include <sys/linker.h> 38 #include <sys/proc.h> 39 40 #include <sys/mplock2.h> 41 42 MALLOC_DEFINE(M_MODULE, "module", "module data structures"); 43 44 typedef TAILQ_HEAD(, module) modulelist_t; 45 struct module { 46 TAILQ_ENTRY(module) link; /* chain together all modules */ 47 TAILQ_ENTRY(module) flink; /* all modules in a file */ 48 struct linker_file* file; /* file which contains this module */ 49 int refs; /* reference count */ 50 int id; /* unique id number */ 51 char *name; /* module name */ 52 modeventhand_t handler; /* event handler */ 53 void *arg; /* argument for handler */ 54 modspecific_t data; /* module specific data */ 55 }; 56 57 #define MOD_EVENT(mod, type) (mod)->handler((mod), (type), (mod)->arg) 58 59 static modulelist_t modules = TAILQ_HEAD_INITIALIZER(modules); 60 static int nextid = 1; 61 62 static void module_shutdown(void*, int); 63 64 static int 65 modevent_nop(module_t mod, int what, void* arg) 66 { 67 return 0; 68 } 69 70 71 static void 72 module_init(void* arg) 73 { 74 TAILQ_INIT(&modules); 75 EVENTHANDLER_REGISTER(shutdown_post_sync, module_shutdown, NULL, 76 SHUTDOWN_PRI_DEFAULT); 77 } 78 79 SYSINIT(module, SI_BOOT2_KLD, SI_ORDER_FIRST, module_init, 0); 80 81 static void 82 module_shutdown(void* arg1, int arg2) 83 { 84 module_t mod; 85 86 for (mod = TAILQ_FIRST(&modules); mod; mod = TAILQ_NEXT(mod, link)) 87 MOD_EVENT(mod, MOD_SHUTDOWN); 88 } 89 90 void 91 module_register_init(const void *arg) 92 { 93 const moduledata_t* data = (const moduledata_t*) arg; 94 int error; 95 module_t mod; 96 97 mod = module_lookupbyname(data->name); 98 if (mod == NULL) { 99 #if 0 100 panic("module_register_init: module named %s not found", data->name); 101 #else 102 /* temporary kludge until kernel `file' attachment registers modules */ 103 error = module_register(data, linker_kernel_file); 104 if (error) 105 panic("module_register_init: register of module failed! %d", error); 106 mod = module_lookupbyname(data->name); 107 if (mod == NULL) 108 panic("module_register_init: module STILL not found!"); 109 #endif 110 } 111 error = MOD_EVENT(mod, MOD_LOAD); 112 if (error) { 113 module_unload(mod); /* ignore error */ 114 module_release(mod); 115 kprintf("module_register_init: MOD_LOAD (%s, %lx, %p) error %d\n", 116 data->name, (u_long)(uintfptr_t)data->evhand, data->priv, error); 117 } 118 } 119 120 int 121 module_register(const moduledata_t *data, linker_file_t container) 122 { 123 size_t namelen; 124 module_t newmod; 125 126 newmod = module_lookupbyname(data->name); 127 if (newmod != NULL) { 128 kprintf("module_register: module %s already exists!\n", data->name); 129 return EEXIST; 130 } 131 namelen = strlen(data->name) + 1; 132 newmod = (module_t) kmalloc(sizeof(struct module) + namelen, 133 M_MODULE, M_WAITOK); 134 135 newmod->refs = 1; 136 newmod->id = nextid++; 137 newmod->name = (char *) (newmod + 1); 138 strcpy(newmod->name, data->name); 139 newmod->handler = data->evhand ? data->evhand : modevent_nop; 140 newmod->arg = data->priv; 141 bzero(&newmod->data, sizeof(newmod->data)); 142 TAILQ_INSERT_TAIL(&modules, newmod, link); 143 144 if (container == NULL) 145 container = linker_current_file; 146 if (container) 147 TAILQ_INSERT_TAIL(&container->modules, newmod, flink); 148 newmod->file = container; 149 150 return 0; 151 } 152 153 void 154 module_reference(module_t mod) 155 { 156 MOD_DPF(REFS, ("module_reference: before, refs=%d\n", mod->refs)); 157 158 mod->refs++; 159 } 160 161 /* 162 * module_release() 163 * 164 * Release ref on the module and return the new reference count. If 0 165 * is returned, the module has been removed from its list and freed. 166 */ 167 int 168 module_release(module_t mod) 169 { 170 int rc; 171 172 if (mod->refs <= 0) 173 panic("module_release: bad reference count"); 174 175 MOD_DPF(REFS, ("module_release: before, refs=%d\n", mod->refs)); 176 177 rc = --mod->refs; 178 if (rc == 0) { 179 TAILQ_REMOVE(&modules, mod, link); 180 if (mod->file) { 181 TAILQ_REMOVE(&mod->file->modules, mod, flink); 182 } 183 kfree(mod, M_MODULE); 184 } 185 return(rc); 186 } 187 188 module_t 189 module_lookupbyname(const char* name) 190 { 191 module_t mod; 192 193 for (mod = TAILQ_FIRST(&modules); mod; mod = TAILQ_NEXT(mod, link)) { 194 if (!strcmp(mod->name, name)) 195 return mod; 196 } 197 198 return NULL; 199 } 200 201 module_t 202 module_lookupbyid(int modid) 203 { 204 module_t mod; 205 206 for (mod = TAILQ_FIRST(&modules); mod; mod = TAILQ_NEXT(mod, link)) { 207 if (mod->id == modid) 208 return mod; 209 } 210 211 return NULL; 212 } 213 214 int 215 module_unload(module_t mod) 216 { 217 int error; 218 219 error = MOD_EVENT(mod, MOD_UNLOAD); 220 /*sync_devs();*/ 221 return (error); 222 } 223 224 int 225 module_getid(module_t mod) 226 { 227 return mod->id; 228 } 229 230 module_t 231 module_getfnext(module_t mod) 232 { 233 return TAILQ_NEXT(mod, flink); 234 } 235 236 void 237 module_setspecific(module_t mod, modspecific_t *datap) 238 { 239 mod->data = *datap; 240 } 241 242 /* 243 * Syscalls. 244 * 245 * MPALMOSTSAFE 246 */ 247 int 248 sys_modnext(struct modnext_args *uap) 249 { 250 module_t mod; 251 int error; 252 253 error = 0; 254 get_mplock(); 255 uap->sysmsg_result = -1; 256 if (uap->modid == 0) { 257 mod = TAILQ_FIRST(&modules); 258 if (mod) 259 uap->sysmsg_result = mod->id; 260 else 261 error = ENOENT; 262 goto done; 263 } 264 265 mod = module_lookupbyid(uap->modid); 266 if (!mod) { 267 error = ENOENT; 268 goto done; 269 } 270 271 if (TAILQ_NEXT(mod, link)) 272 uap->sysmsg_result = TAILQ_NEXT(mod, link)->id; 273 else 274 uap->sysmsg_result = 0; 275 done: 276 rel_mplock(); 277 return error; 278 } 279 280 /* 281 * MPALMOSTSAFE 282 */ 283 int 284 sys_modfnext(struct modfnext_args *uap) 285 { 286 module_t mod; 287 int error; 288 289 get_mplock(); 290 uap->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 uap->sysmsg_result = TAILQ_NEXT(mod, flink)->id; 300 else 301 uap->sysmsg_result = 0; 302 error = 0; 303 done: 304 rel_mplock(); 305 return error; 306 } 307 308 struct module_stat_v1 { 309 int version; /* set to sizeof(struct module_stat) */ 310 char name[MAXMODNAME]; 311 int refs; 312 int id; 313 }; 314 315 /* 316 * MPALMOSTSAFE 317 */ 318 int 319 sys_modstat(struct modstat_args *uap) 320 { 321 module_t mod; 322 int error; 323 int namelen; 324 int version; 325 struct module_stat* stat; 326 327 get_mplock(); 328 mod = module_lookupbyid(uap->modid); 329 if (!mod) { 330 error = ENOENT; 331 goto out; 332 } 333 334 stat = uap->stat; 335 336 /* 337 * Check the version of the user's structure. 338 */ 339 if ((error = copyin(&stat->version, &version, sizeof(version))) != 0) 340 goto out; 341 if (version != sizeof(struct module_stat_v1) 342 && version != sizeof(struct module_stat)) { 343 error = EINVAL; 344 goto out; 345 } 346 347 namelen = strlen(mod->name) + 1; 348 if (namelen > MAXMODNAME) 349 namelen = MAXMODNAME; 350 if ((error = copyout(mod->name, &stat->name[0], namelen)) != 0) 351 goto out; 352 353 if ((error = copyout(&mod->refs, &stat->refs, sizeof(int))) != 0) 354 goto out; 355 if ((error = copyout(&mod->id, &stat->id, sizeof(int))) != 0) 356 goto out; 357 358 /* 359 * >v1 stat includes module data. 360 */ 361 if (version == sizeof(struct module_stat)) { 362 if ((error = copyout(&mod->data, &stat->data, sizeof(mod->data))) != 0) 363 goto out; 364 } 365 366 uap->sysmsg_result = 0; 367 368 out: 369 rel_mplock(); 370 return error; 371 } 372 373 /* 374 * MPALMOSTSAFE 375 */ 376 int 377 sys_modfind(struct modfind_args *uap) 378 { 379 int error; 380 char name[MAXMODNAME]; 381 module_t mod; 382 383 get_mplock(); 384 if ((error = copyinstr(uap->name, name, sizeof name, 0)) != 0) 385 goto out; 386 387 mod = module_lookupbyname(name); 388 if (!mod) 389 error = ENOENT; 390 else 391 uap->sysmsg_result = mod->id; 392 393 out: 394 rel_mplock(); 395 return error; 396 } 397