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 #define M_MODULE M_TEMP /* XXX */ 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; 58 static int nextid = 1; 59 60 static void module_shutdown(void*, int); 61 62 static int 63 modevent_nop(module_t mod, int what, void* arg) 64 { 65 return 0; 66 } 67 68 69 static void 70 module_init(void* arg) 71 { 72 TAILQ_INIT(&modules); 73 EVENTHANDLER_REGISTER(shutdown_post_sync, module_shutdown, NULL, 74 SHUTDOWN_PRI_DEFAULT); 75 } 76 77 SYSINIT(module, SI_SUB_KLD, SI_ORDER_FIRST, module_init, 0); 78 79 static void 80 module_shutdown(void* arg1, int arg2) 81 { 82 module_t mod; 83 84 for (mod = TAILQ_FIRST(&modules); mod; mod = TAILQ_NEXT(mod, link)) 85 MOD_EVENT(mod, MOD_SHUTDOWN); 86 } 87 88 void 89 module_register_init(const void *arg) 90 { 91 const moduledata_t* data = (const moduledata_t*) arg; 92 int error; 93 module_t mod; 94 95 mod = module_lookupbyname(data->name); 96 if (mod == NULL) { 97 #if 0 98 panic("module_register_init: module named %s not found\n", data->name); 99 #else 100 /* temporary kludge until kernel `file' attachment registers modules */ 101 error = module_register(data, linker_kernel_file); 102 if (error) 103 panic("module_register_init: register of module failed! %d", error); 104 mod = module_lookupbyname(data->name); 105 if (mod == NULL) 106 panic("module_register_init: module STILL not found!"); 107 #endif 108 } 109 error = MOD_EVENT(mod, MOD_LOAD); 110 if (error) { 111 MOD_EVENT(mod, MOD_UNLOAD); 112 module_release(mod); 113 printf("module_register_init: MOD_LOAD (%s, %lx, %p) error %d\n", 114 data->name, (u_long)(uintfptr_t)data->evhand, data->priv, error); 115 } 116 } 117 118 int 119 module_register(const moduledata_t *data, linker_file_t container) 120 { 121 size_t namelen; 122 module_t newmod; 123 124 newmod = module_lookupbyname(data->name); 125 if (newmod != NULL) { 126 printf("module_register: module %s already exists!\n", data->name); 127 return EEXIST; 128 } 129 namelen = strlen(data->name) + 1; 130 newmod = (module_t) malloc(sizeof(struct module) + namelen, 131 M_MODULE, M_WAITOK); 132 if (newmod == 0) 133 return ENOMEM; 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 void 162 module_release(module_t mod) 163 { 164 if (mod->refs <= 0) 165 panic("module_release: bad reference count"); 166 167 MOD_DPF(REFS, ("module_release: before, refs=%d\n", mod->refs)); 168 169 mod->refs--; 170 if (mod->refs == 0) { 171 TAILQ_REMOVE(&modules, mod, link); 172 if (mod->file) { 173 TAILQ_REMOVE(&mod->file->modules, mod, flink); 174 } 175 free(mod, M_MODULE); 176 } 177 } 178 179 module_t 180 module_lookupbyname(const char* name) 181 { 182 module_t mod; 183 184 for (mod = TAILQ_FIRST(&modules); mod; mod = TAILQ_NEXT(mod, link)) { 185 if (!strcmp(mod->name, name)) 186 return mod; 187 } 188 189 return 0; 190 } 191 192 module_t 193 module_lookupbyid(int modid) 194 { 195 module_t mod; 196 197 for (mod = TAILQ_FIRST(&modules); mod; mod = TAILQ_NEXT(mod, link)) { 198 if (mod->id == modid) 199 return mod; 200 } 201 202 return 0; 203 } 204 205 int 206 module_unload(module_t mod) 207 { 208 return MOD_EVENT(mod, MOD_UNLOAD); 209 } 210 211 int 212 module_getid(module_t mod) 213 { 214 return mod->id; 215 } 216 217 module_t 218 module_getfnext(module_t mod) 219 { 220 return TAILQ_NEXT(mod, flink); 221 } 222 223 void 224 module_setspecific(module_t mod, modspecific_t *datap) 225 { 226 mod->data = *datap; 227 } 228 229 /* 230 * Syscalls. 231 */ 232 int 233 modnext(struct proc* p, struct modnext_args* uap) 234 { 235 module_t mod; 236 237 p->p_retval[0] = -1; 238 if (SCARG(uap, modid) == 0) { 239 mod = TAILQ_FIRST(&modules); 240 if (mod) { 241 p->p_retval[0] = mod->id; 242 return 0; 243 } else 244 return ENOENT; 245 } 246 247 mod = module_lookupbyid(SCARG(uap, modid)); 248 if (!mod) 249 return ENOENT; 250 251 if (TAILQ_NEXT(mod, link)) 252 p->p_retval[0] = TAILQ_NEXT(mod, link)->id; 253 else 254 p->p_retval[0] = 0; 255 return 0; 256 } 257 258 int 259 modfnext(struct proc* p, struct modfnext_args* uap) 260 { 261 module_t mod; 262 263 p->p_retval[0] = -1; 264 265 mod = module_lookupbyid(SCARG(uap, modid)); 266 if (!mod) 267 return ENOENT; 268 269 if (TAILQ_NEXT(mod, flink)) 270 p->p_retval[0] = TAILQ_NEXT(mod, flink)->id; 271 else 272 p->p_retval[0] = 0; 273 return 0; 274 } 275 276 struct module_stat_v1 { 277 int version; /* set to sizeof(struct module_stat) */ 278 char name[MAXMODNAME]; 279 int refs; 280 int id; 281 }; 282 283 int 284 modstat(struct proc* p, struct modstat_args* uap) 285 { 286 module_t mod; 287 int error = 0; 288 int namelen; 289 int version; 290 struct module_stat* stat; 291 292 mod = module_lookupbyid(SCARG(uap, modid)); 293 if (!mod) 294 return ENOENT; 295 296 stat = SCARG(uap, stat); 297 298 /* 299 * Check the version of the user's structure. 300 */ 301 if ((error = copyin(&stat->version, &version, sizeof(version))) != 0) 302 goto out; 303 if (version != sizeof(struct module_stat_v1) 304 && version != sizeof(struct module_stat)) { 305 error = EINVAL; 306 goto out; 307 } 308 309 namelen = strlen(mod->name) + 1; 310 if (namelen > MAXMODNAME) 311 namelen = MAXMODNAME; 312 if ((error = copyout(mod->name, &stat->name[0], namelen)) != 0) 313 goto out; 314 315 if ((error = copyout(&mod->refs, &stat->refs, sizeof(int))) != 0) 316 goto out; 317 if ((error = copyout(&mod->id, &stat->id, sizeof(int))) != 0) 318 goto out; 319 320 /* 321 * >v1 stat includes module data. 322 */ 323 if (version == sizeof(struct module_stat)) { 324 if ((error = copyout(&mod->data, &stat->data, sizeof(mod->data))) != 0) 325 goto out; 326 } 327 328 p->p_retval[0] = 0; 329 330 out: 331 return error; 332 } 333 334 int 335 modfind(struct proc* p, struct modfind_args* uap) 336 { 337 int error = 0; 338 char name[MAXMODNAME]; 339 module_t mod; 340 341 if ((error = copyinstr(SCARG(uap, name), name, sizeof name, 0)) != 0) 342 goto out; 343 344 mod = module_lookupbyname(name); 345 if (!mod) 346 error = ENOENT; 347 else 348 p->p_retval[0] = mod->id; 349 350 out: 351 return error; 352 } 353