1 #ifndef _LINUX_MODULE_H
2 #define _LINUX_MODULE_H
3 /*
4 * Dynamic loading of modules into the kernel.
5 *
6 * Rewritten by Richard Henderson <rth@tamu.edu> Dec 1996
7 * Rewritten again by Rusty Russell, 2002
8 */
9 #include <linux/config.h>
10 #include <linux/sched.h>
11 #include <linux/spinlock.h>
12 #include <linux/list.h>
13 #include <linux/stat.h>
14 #include <linux/compiler.h>
15 #include <linux/cache.h>
16 #include <linux/kmod.h>
17 #include <linux/elf.h>
18 #include <linux/stringify.h>
19 #include <asm/local.h>
20
21 #include <asm/module.h>
22
23 /* Not Yet Implemented */
24 #define MODULE_SUPPORTED_DEVICE(name)
25 #define print_modules()
26
27 /* v850 toolchain uses a `_' prefix for all user symbols */
28 #ifndef MODULE_SYMBOL_PREFIX
29 #define MODULE_SYMBOL_PREFIX ""
30 #endif
31
32 #define MODULE_NAME_LEN (64 - sizeof(unsigned long))
33
34 struct kernel_symbol
35 {
36 unsigned long value;
37 const char *name;
38 };
39
40 struct modversion_info
41 {
42 unsigned long crc;
43 char name[MODULE_NAME_LEN];
44 };
45
46 /* These are either module local, or the kernel's dummy ones. */
47 extern int init_module(void);
48 extern void cleanup_module(void);
49
50 /* Archs provide a method of finding the correct exception table. */
51 struct exception_table_entry;
52
53 const struct exception_table_entry *
54 search_extable(const struct exception_table_entry *first,
55 const struct exception_table_entry *last,
56 unsigned long value);
57
58 #ifdef MODULE
59 #define ___module_cat(a,b) __mod_ ## a ## b
60 #define __module_cat(a,b) ___module_cat(a,b)
61 #define __MODULE_INFO(tag, name, info) \
62 static const char __module_cat(name,__LINE__)[] \
63 __attribute__((section(".modinfo"),unused)) = __stringify(tag) "=" info
64
65 #define MODULE_GENERIC_TABLE(gtype,name) \
66 extern const struct gtype##_id __mod_##gtype##_table \
67 __attribute__ ((unused, alias(__stringify(name))))
68
69 #define THIS_MODULE (&__this_module)
70
71 #else /* !MODULE */
72
73 #define MODULE_GENERIC_TABLE(gtype,name)
74 #define __MODULE_INFO(tag, name, info)
75 #define THIS_MODULE ((struct module *)0)
76 #endif
77
78 /* Generic info of form tag = "info" */
79 #define MODULE_INFO(tag, info) __MODULE_INFO(tag, tag, info)
80
81 /* For userspace: you can also call me... */
82 #define MODULE_ALIAS(_alias) MODULE_INFO(alias, _alias)
83
84 /*
85 * The following license idents are currently accepted as indicating free
86 * software modules
87 *
88 * "GPL" [GNU Public License v2 or later]
89 * "GPL v2" [GNU Public License v2]
90 * "GPL and additional rights" [GNU Public License v2 rights and more]
91 * "Dual BSD/GPL" [GNU Public License v2
92 * or BSD license choice]
93 * "Dual MPL/GPL" [GNU Public License v2
94 * or Mozilla license choice]
95 *
96 * The following other idents are available
97 *
98 * "Proprietary" [Non free products]
99 *
100 * There are dual licensed components, but when running with Linux it is the
101 * GPL that is relevant so this is a non issue. Similarly LGPL linked with GPL
102 * is a GPL combined work.
103 *
104 * This exists for several reasons
105 * 1. So modinfo can show license info for users wanting to vet their setup
106 * is free
107 * 2. So the community can ignore bug reports including proprietary modules
108 * 3. So vendors can do likewise based on their own policies
109 */
110 #define MODULE_LICENSE(_license) MODULE_INFO(license, _license)
111
112 /* Author, ideally of form NAME <EMAIL>[, NAME <EMAIL>]*[ and NAME <EMAIL>] */
113 #define MODULE_AUTHOR(_author) MODULE_INFO(author, _author)
114
115 /* What your module does. */
116 #define MODULE_DESCRIPTION(_description) MODULE_INFO(description, _description)
117
118 /* One for each parameter, describing how to use it. Some files do
119 multiple of these per line, so can't just use MODULE_INFO. */
120 #define MODULE_PARM_DESC(_parm, desc) \
121 __MODULE_INFO(parm, _parm, #_parm ":" desc)
122
123 #define MODULE_DEVICE_TABLE(type,name) \
124 MODULE_GENERIC_TABLE(type##_device,name)
125
126 /* Given an address, look for it in the exception tables */
127 const struct exception_table_entry *search_exception_tables(unsigned long add);
128
129 struct notifier_block;
130
131 #ifdef CONFIG_MODULES
132
133 /* Get/put a kernel symbol (calls must be symmetric) */
134 void *__symbol_get(const char *symbol);
135 void *__symbol_get_gpl(const char *symbol);
136 #define symbol_get(x) ((typeof(&x))(__symbol_get(MODULE_SYMBOL_PREFIX #x)))
137
138 #ifndef __GENKSYMS__
139 #ifdef CONFIG_MODVERSIONS
140 /* Mark the CRC weak since genksyms apparently decides not to
141 * generate a checksums for some symbols */
142 #define __CRC_SYMBOL(sym, sec) \
143 extern void *__crc_##sym __attribute__((weak)); \
144 static const unsigned long __kcrctab_##sym \
145 __attribute__((section("__kcrctab" sec), unused)) \
146 = (unsigned long) &__crc_##sym;
147 #else
148 #define __CRC_SYMBOL(sym, sec)
149 #endif
150
151 /* For every exported symbol, place a struct in the __ksymtab section */
152 #define __EXPORT_SYMBOL(sym, sec) \
153 __CRC_SYMBOL(sym, sec) \
154 static const char __kstrtab_##sym[] \
155 __attribute__((section("__ksymtab_strings"))) \
156 = MODULE_SYMBOL_PREFIX #sym; \
157 static const struct kernel_symbol __ksymtab_##sym \
158 __attribute__((section("__ksymtab" sec), unused)) \
159 = { (unsigned long)&sym, __kstrtab_##sym }
160
161 #define EXPORT_SYMBOL(sym) \
162 __EXPORT_SYMBOL(sym, "")
163
164 #define EXPORT_SYMBOL_GPL(sym) \
165 __EXPORT_SYMBOL(sym, "_gpl")
166
167 #endif
168
169 /* We don't mangle the actual symbol anymore, so no need for
170 * special casing EXPORT_SYMBOL_NOVERS. FIXME: Deprecated */
171 #define EXPORT_SYMBOL_NOVERS(sym) EXPORT_SYMBOL(sym)
172
173 struct module_ref
174 {
175 local_t count;
176 } ____cacheline_aligned;
177
178 enum module_state
179 {
180 MODULE_STATE_LIVE,
181 MODULE_STATE_COMING,
182 MODULE_STATE_GOING,
183 };
184
185 struct module
186 {
187 enum module_state state;
188
189 /* Member of list of modules */
190 struct list_head list;
191
192 /* Unique handle for this module */
193 char name[MODULE_NAME_LEN];
194
195 /* Exported symbols */
196 const struct kernel_symbol *syms;
197 unsigned int num_syms;
198 const unsigned long *crcs;
199
200 /* GPL-only exported symbols. */
201 const struct kernel_symbol *gpl_syms;
202 unsigned int num_gpl_syms;
203 const unsigned long *gpl_crcs;
204
205 /* Exception table */
206 unsigned int num_exentries;
207 const struct exception_table_entry *extable;
208
209 /* Startup function. */
210 int (*init)(void);
211
212 /* If this is non-NULL, vfree after init() returns */
213 void *module_init;
214
215 /* Here is the actual code + data, vfree'd on unload. */
216 void *module_core;
217
218 /* Here are the sizes of the init and core sections */
219 unsigned long init_size, core_size;
220
221 /* The size of the executable code in each section. */
222 unsigned long init_text_size, core_text_size;
223
224 /* Arch-specific module values */
225 struct mod_arch_specific arch;
226
227 /* Am I unsafe to unload? */
228 int unsafe;
229
230 /* Am I GPL-compatible */
231 int license_gplok;
232
233 #ifdef CONFIG_MODULE_UNLOAD
234 /* Reference counts */
235 struct module_ref ref[NR_CPUS];
236
237 /* What modules depend on me? */
238 struct list_head modules_which_use_me;
239
240 /* Who is waiting for us to be unloaded */
241 struct task_struct *waiter;
242
243 /* Destruction function. */
244 void (*exit)(void);
245 #endif
246
247 #ifdef CONFIG_KALLSYMS
248 /* We keep the symbol and string tables for kallsyms. */
249 Elf_Sym *symtab;
250 unsigned long num_symtab;
251 char *strtab;
252 #endif
253
254 /* Per-cpu data. */
255 void *percpu;
256
257 /* The command line arguments (may be mangled). People like
258 keeping pointers to this stuff */
259 char *args;
260 };
261
262 /* FIXME: It'd be nice to isolate modules during init, too, so they
263 aren't used before they (may) fail. But presently too much code
264 (IDE & SCSI) require entry into the module during init.*/
265 static inline int module_is_live(struct module *mod)
266 {
267 return mod->state != MODULE_STATE_GOING;
268 }
269
270 /* Is this address in a module? */
271 struct module *module_text_address(unsigned long addr);
272
273 /* Returns module and fills in value, defined and namebuf, or NULL if
274 symnum out of range. */
275 struct module *module_get_kallsym(unsigned int symnum,
276 unsigned long *value,
277 char *type,
278 char namebuf[128]);
279 int is_exported(const char *name, const struct module *mod);
280
281 extern void __module_put_and_exit(struct module *mod, long code)
282 __attribute__((noreturn));
283 #define module_put_and_exit(code) __module_put_and_exit(THIS_MODULE, code);
284
285 #ifdef CONFIG_MODULE_UNLOAD
286 unsigned int module_refcount(struct module *mod);
287 void __symbol_put(const char *symbol);
288 #define symbol_put(x) __symbol_put(MODULE_SYMBOL_PREFIX #x)
289 void symbol_put_addr(void *addr);
290
291 /* Sometimes we know we already have a refcount, and it's easier not
292 to handle the error case (which only happens with rmmod --wait). */
293 static inline void __module_get(struct module *module)
294 {
295 if (module) {
296 BUG_ON(module_refcount(module) == 0);
297 local_inc(&module->ref[get_cpu()].count);
298 put_cpu();
299 }
300 }
301
302 static inline int try_module_get(struct module *module)
303 {
304 int ret = 1;
305
306 if (module) {
307 unsigned int cpu = get_cpu();
308 if (likely(module_is_live(module)))
309 local_inc(&module->ref[cpu].count);
310 else
311 ret = 0;
312 put_cpu();
313 }
314 return ret;
315 }
316
317 static inline void module_put(struct module *module)
318 {
319 if (module) {
320 unsigned int cpu = get_cpu();
321 local_dec(&module->ref[cpu].count);
322 /* Maybe they're waiting for us to drop reference? */
323 if (unlikely(!module_is_live(module)))
324 wake_up_process(module->waiter);
325 put_cpu();
326 }
327 }
328
329 #else /*!CONFIG_MODULE_UNLOAD*/
330 static inline int try_module_get(struct module *module)
331 {
332 return !module || module_is_live(module);
333 }
334 static inline void module_put(struct module *module)
335 {
336 }
337 static inline void __module_get(struct module *module)
338 {
339 }
340 #define symbol_put(x) do { } while(0)
341 #define symbol_put_addr(p) do { } while(0)
342
343 #endif /* CONFIG_MODULE_UNLOAD */
344
345 /* This is a #define so the string doesn't get put in every .o file */
346 #define module_name(mod) \
347 ({ \
348 struct module *__mod = (mod); \
349 __mod ? __mod->name : "kernel"; \
350 })
351
352 #define __unsafe(mod) \
353 do { \
354 if (mod && !(mod)->unsafe) { \
355 printk(KERN_WARNING \
356 "Module %s cannot be unloaded due to unsafe usage in" \
357 " %s:%u\n", (mod)->name, __FILE__, __LINE__); \
358 (mod)->unsafe = 1; \
359 } \
360 } while(0)
361
362 /* For kallsyms to ask for address resolution. NULL means not found. */
363 const char *module_address_lookup(unsigned long addr,
364 unsigned long *symbolsize,
365 unsigned long *offset,
366 char **modname);
367
368 /* For extable.c to search modules' exception tables. */
369 const struct exception_table_entry *search_module_extables(unsigned long addr);
370
371 int register_module_notifier(struct notifier_block * nb);
372 int unregister_module_notifier(struct notifier_block * nb);
373
374 #else /* !CONFIG_MODULES... */
375 #define EXPORT_SYMBOL(sym)
376 #define EXPORT_SYMBOL_GPL(sym)
377 #define EXPORT_SYMBOL_NOVERS(sym)
378
379 /* Given an address, look for it in the exception tables. */
380 static inline const struct exception_table_entry *
381 search_module_extables(unsigned long addr)
382 {
383 return NULL;
384 }
385
386 /* Is this address in a module? */
387 static inline struct module *module_text_address(unsigned long addr)
388 {
389 return NULL;
390 }
391
392 /* Get/put a kernel symbol (calls should be symmetric) */
393 #define symbol_get(x) ({ extern typeof(x) x __attribute__((weak)); &(x); })
394 #define symbol_put(x) do { } while(0)
395 #define symbol_put_addr(x) do { } while(0)
396
397 static inline void __module_get(struct module *module)
398 {
399 }
400
401 static inline int try_module_get(struct module *module)
402 {
403 return 1;
404 }
405
406 static inline void module_put(struct module *module)
407 {
408 }
409
410 #define module_name(mod) "kernel"
411
412 #define __unsafe(mod)
413
414 /* For kallsyms to ask for address resolution. NULL means not found. */
415 static inline const char *module_address_lookup(unsigned long addr,
416 unsigned long *symbolsize,
417 unsigned long *offset,
418 char **modname)
419 {
420 return NULL;
421 }
422
423 static inline struct module *module_get_kallsym(unsigned int symnum,
424 unsigned long *value,
425 char *type,
426 char namebuf[128])
427 {
428 return NULL;
429 }
430
431 static inline int is_exported(const char *name, const struct module *mod)
432 {
433 return 0;
434 }
435
436 static inline int register_module_notifier(struct notifier_block * nb)
437 {
438 /* no events will happen anyway, so this can always succeed */
439 return 0;
440 }
441
442 static inline int unregister_module_notifier(struct notifier_block * nb)
443 {
444 return 0;
445 }
446
447 #define module_put_and_exit(code) do_exit(code)
448
449 #endif /* CONFIG_MODULES */
450
451 #ifdef MODULE
452 extern struct module __this_module;
453 #ifdef KBUILD_MODNAME
454 /* We make the linker do some of the work. */
455 struct module __this_module
456 __attribute__((section(".gnu.linkonce.this_module"))) = {
457 .name = __stringify(KBUILD_MODNAME),
458 .init = init_module,
459 #ifdef CONFIG_MODULE_UNLOAD
460 .exit = cleanup_module,
461 #endif
462 };
463 #endif /* KBUILD_MODNAME */
464 #endif /* MODULE */
465
466 #define symbol_request(x) try_then_request_module(symbol_get(x), "symbol:" #x)
467
468 /* BELOW HERE ALL THESE ARE OBSOLETE AND WILL VANISH */
469
470 struct obsolete_modparm {
471 char name[64];
472 char type[64-sizeof(void *)];
473 void *addr;
474 };
475 #ifdef MODULE
476 /* DEPRECATED: Do not use. */
477 #define MODULE_PARM(var,type) \
478 struct obsolete_modparm __parm_##var __attribute__((section("__obsparm"))) = \
479 { __stringify(var), type };
480
481 static inline void __deprecated MOD_INC_USE_COUNT(struct module *module)
482 {
483 __unsafe(module);
484
485 #if defined(CONFIG_MODULE_UNLOAD) && defined(MODULE)
486 local_inc(&module->ref[get_cpu()].count);
487 put_cpu();
488 #else
489 (void)try_module_get(module);
490 #endif
491 }
492
493 static inline void __deprecated MOD_DEC_USE_COUNT(struct module *module)
494 {
495 module_put(module);
496 }
497
498 #define MOD_INC_USE_COUNT MOD_INC_USE_COUNT(THIS_MODULE)
499 #define MOD_DEC_USE_COUNT MOD_DEC_USE_COUNT(THIS_MODULE)
500 #else
501 #define MODULE_PARM(var,type)
502 #define MOD_INC_USE_COUNT do { } while (0)
503 #define MOD_DEC_USE_COUNT do { } while (0)
504 #endif
505
506 #define __MODULE_STRING(x) __stringify(x)
507
508 /* Use symbol_get and symbol_put instead. You'll thank me. */
509 #define HAVE_INTER_MODULE
510 extern void inter_module_register(const char *, struct module *, const void *);
511 extern void inter_module_unregister(const char *);
512 extern const void *inter_module_get(const char *);
513 extern const void *inter_module_get_request(const char *, const char *);
514 extern void inter_module_put(const char *);
515
516 #endif /* _LINUX_MODULE_H */
517
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