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 * $DragonFly: src/sys/kern/kern_module.c,v 1.5 2003/07/30 00:19:14 dillon Exp $ 28 */ 29 30 #include <sys/param.h> 31 #include <sys/kernel.h> 32 #include <sys/systm.h> 33 #include <sys/eventhandler.h> 34 #include <sys/malloc.h> 35 #include <sys/sysproto.h> 36 #include <sys/sysent.h> 37 #include <sys/module.h> 38 #include <sys/linker.h> 39 #include <sys/proc.h> 40 41 #define M_MODULE M_TEMP /* XXX */ 42 43 typedef TAILQ_HEAD(, module) modulelist_t; 44 struct module { 45 TAILQ_ENTRY(module) link; /* chain together all modules */ 46 TAILQ_ENTRY(module) flink; /* all modules in a file */ 47 struct linker_file* file; /* file which contains this module */ 48 int refs; /* reference count */ 49 int id; /* unique id number */ 50 char *name; /* module name */ 51 modeventhand_t handler; /* event handler */ 52 void *arg; /* argument for handler */ 53 modspecific_t data; /* module specific data */ 54 }; 55 56 #define MOD_EVENT(mod, type) (mod)->handler((mod), (type), (mod)->arg) 57 58 static modulelist_t modules; 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_SUB_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\n", 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 MOD_EVENT(mod, MOD_UNLOAD); 113 module_release(mod); 114 printf("module_register_init: MOD_LOAD (%s, %lx, %p) error %d\n", 115 data->name, (u_long)(uintfptr_t)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 printf("module_register: module %s already exists!\n", data->name); 128 return EEXIST; 129 } 130 namelen = strlen(data->name) + 1; 131 newmod = (module_t) malloc(sizeof(struct module) + namelen, 132 M_MODULE, M_WAITOK); 133 if (newmod == 0) 134 return ENOMEM; 135 136 newmod->refs = 1; 137 newmod->id = nextid++; 138 newmod->name = (char *) (newmod + 1); 139 strcpy(newmod->name, data->name); 140 newmod->handler = data->evhand ? data->evhand : modevent_nop; 141 newmod->arg = data->priv; 142 bzero(&newmod->data, sizeof(newmod->data)); 143 TAILQ_INSERT_TAIL(&modules, newmod, link); 144 145 if (container == NULL) 146 container = linker_current_file; 147 if (container) 148 TAILQ_INSERT_TAIL(&container->modules, newmod, flink); 149 newmod->file = container; 150 151 return 0; 152 } 153 154 void 155 module_reference(module_t mod) 156 { 157 MOD_DPF(REFS, ("module_reference: before, refs=%d\n", mod->refs)); 158 159 mod->refs++; 160 } 161 162 void 163 module_release(module_t mod) 164 { 165 if (mod->refs <= 0) 166 panic("module_release: bad reference count"); 167 168 MOD_DPF(REFS, ("module_release: before, refs=%d\n", mod->refs)); 169 170 mod->refs--; 171 if (mod->refs == 0) { 172 TAILQ_REMOVE(&modules, mod, link); 173 if (mod->file) { 174 TAILQ_REMOVE(&mod->file->modules, mod, flink); 175 } 176 free(mod, M_MODULE); 177 } 178 } 179 180 module_t 181 module_lookupbyname(const char* name) 182 { 183 module_t mod; 184 185 for (mod = TAILQ_FIRST(&modules); mod; mod = TAILQ_NEXT(mod, link)) { 186 if (!strcmp(mod->name, name)) 187 return mod; 188 } 189 190 return 0; 191 } 192 193 module_t 194 module_lookupbyid(int modid) 195 { 196 module_t mod; 197 198 for (mod = TAILQ_FIRST(&modules); mod; mod = TAILQ_NEXT(mod, link)) { 199 if (mod->id == modid) 200 return mod; 201 } 202 203 return 0; 204 } 205 206 int 207 module_unload(module_t mod) 208 { 209 return MOD_EVENT(mod, MOD_UNLOAD); 210 } 211 212 int 213 module_getid(module_t mod) 214 { 215 return mod->id; 216 } 217 218 module_t 219 module_getfnext(module_t mod) 220 { 221 return TAILQ_NEXT(mod, flink); 222 } 223 224 void 225 module_setspecific(module_t mod, modspecific_t *datap) 226 { 227 mod->data = *datap; 228 } 229 230 /* 231 * Syscalls. 232 */ 233 int 234 modnext(struct modnext_args *uap) 235 { 236 module_t mod; 237 238 uap->sysmsg_result = -1; 239 if (SCARG(uap, modid) == 0) { 240 mod = TAILQ_FIRST(&modules); 241 if (mod) { 242 uap->sysmsg_result = mod->id; 243 return 0; 244 } else 245 return ENOENT; 246 } 247 248 mod = module_lookupbyid(SCARG(uap, modid)); 249 if (!mod) 250 return ENOENT; 251 252 if (TAILQ_NEXT(mod, link)) 253 uap->sysmsg_result = TAILQ_NEXT(mod, link)->id; 254 else 255 uap->sysmsg_result = 0; 256 return 0; 257 } 258 259 int 260 modfnext(struct modfnext_args *uap) 261 { 262 module_t mod; 263 264 uap->sysmsg_result = -1; 265 266 mod = module_lookupbyid(SCARG(uap, modid)); 267 if (!mod) 268 return ENOENT; 269 270 if (TAILQ_NEXT(mod, flink)) 271 uap->sysmsg_result = TAILQ_NEXT(mod, flink)->id; 272 else 273 uap->sysmsg_result = 0; 274 return 0; 275 } 276 277 struct module_stat_v1 { 278 int version; /* set to sizeof(struct module_stat) */ 279 char name[MAXMODNAME]; 280 int refs; 281 int id; 282 }; 283 284 int 285 modstat(struct modstat_args *uap) 286 { 287 module_t mod; 288 int error = 0; 289 int namelen; 290 int version; 291 struct module_stat* stat; 292 293 mod = module_lookupbyid(SCARG(uap, modid)); 294 if (!mod) 295 return ENOENT; 296 297 stat = SCARG(uap, stat); 298 299 /* 300 * Check the version of the user's structure. 301 */ 302 if ((error = copyin(&stat->version, &version, sizeof(version))) != 0) 303 goto out; 304 if (version != sizeof(struct module_stat_v1) 305 && version != sizeof(struct module_stat)) { 306 error = EINVAL; 307 goto out; 308 } 309 310 namelen = strlen(mod->name) + 1; 311 if (namelen > MAXMODNAME) 312 namelen = MAXMODNAME; 313 if ((error = copyout(mod->name, &stat->name[0], namelen)) != 0) 314 goto out; 315 316 if ((error = copyout(&mod->refs, &stat->refs, sizeof(int))) != 0) 317 goto out; 318 if ((error = copyout(&mod->id, &stat->id, sizeof(int))) != 0) 319 goto out; 320 321 /* 322 * >v1 stat includes module data. 323 */ 324 if (version == sizeof(struct module_stat)) { 325 if ((error = copyout(&mod->data, &stat->data, sizeof(mod->data))) != 0) 326 goto out; 327 } 328 329 uap->sysmsg_result = 0; 330 331 out: 332 return error; 333 } 334 335 int 336 modfind(struct modfind_args *uap) 337 { 338 int error = 0; 339 char name[MAXMODNAME]; 340 module_t mod; 341 342 if ((error = copyinstr(SCARG(uap, name), name, sizeof name, 0)) != 0) 343 goto out; 344 345 mod = module_lookupbyname(name); 346 if (!mod) 347 error = ENOENT; 348 else 349 uap->sysmsg_result = mod->id; 350 351 out: 352 return error; 353 } 354