syscall messaging 3: Expand the 'header' that goes in front of the syscall
[dragonfly.git] / sys / kern / kern_module.c
CommitLineData
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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 $
c7114eea 27 * $DragonFly: src/sys/kern/kern_module.c,v 1.5 2003/07/30 00:19:14 dillon Exp $
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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
43typedef TAILQ_HEAD(, module) modulelist_t;
44struct 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
58static modulelist_t modules;
59static int nextid = 1;
60
61static void module_shutdown(void*, int);
62
63static int
64modevent_nop(module_t mod, int what, void* arg)
65{
66 return 0;
67}
68
69
70static void
71module_init(void* arg)
72{
73 TAILQ_INIT(&modules);
74 EVENTHANDLER_REGISTER(shutdown_post_sync, module_shutdown, NULL,
75 SHUTDOWN_PRI_DEFAULT);
76}
77
78SYSINIT(module, SI_SUB_KLD, SI_ORDER_FIRST, module_init, 0);
79
80static void
81module_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
89void
90module_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
119int
120module_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
154void
155module_reference(module_t mod)
156{
157 MOD_DPF(REFS, ("module_reference: before, refs=%d\n", mod->refs));
158
159 mod->refs++;
160}
161
162void
163module_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
180module_t
181module_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
193module_t
194module_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
206int
207module_unload(module_t mod)
208{
209 return MOD_EVENT(mod, MOD_UNLOAD);
210}
211
212int
213module_getid(module_t mod)
214{
215 return mod->id;
216}
217
218module_t
219module_getfnext(module_t mod)
220{
221 return TAILQ_NEXT(mod, flink);
222}
223
224void
225module_setspecific(module_t mod, modspecific_t *datap)
226{
227 mod->data = *datap;
228}
229
230/*
231 * Syscalls.
232 */
233int
41c20dac 234modnext(struct modnext_args *uap)
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235{
236 module_t mod;
237
c7114eea 238 uap->sysmsg_result = -1;
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239 if (SCARG(uap, modid) == 0) {
240 mod = TAILQ_FIRST(&modules);
241 if (mod) {
c7114eea 242 uap->sysmsg_result = mod->id;
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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))
c7114eea 253 uap->sysmsg_result = TAILQ_NEXT(mod, link)->id;
984263bc 254 else
c7114eea 255 uap->sysmsg_result = 0;
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256 return 0;
257}
258
259int
41c20dac 260modfnext(struct modfnext_args *uap)
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261{
262 module_t mod;
263
c7114eea 264 uap->sysmsg_result = -1;
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265
266 mod = module_lookupbyid(SCARG(uap, modid));
267 if (!mod)
268 return ENOENT;
269
270 if (TAILQ_NEXT(mod, flink))
c7114eea 271 uap->sysmsg_result = TAILQ_NEXT(mod, flink)->id;
984263bc 272 else
c7114eea 273 uap->sysmsg_result = 0;
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274 return 0;
275}
276
277struct module_stat_v1 {
278 int version; /* set to sizeof(struct module_stat) */
279 char name[MAXMODNAME];
280 int refs;
281 int id;
282};
283
284int
41c20dac 285modstat(struct modstat_args *uap)
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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
c7114eea 329 uap->sysmsg_result = 0;
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330
331out:
332 return error;
333}
334
335int
41c20dac 336modfind(struct modfind_args *uap)
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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
c7114eea 349 uap->sysmsg_result = mod->id;
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350
351out:
352 return error;
353}