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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/sched.h>
10 #include <linux/spinlock.h>
11 #include <linux/list.h>
12 #include <linux/stat.h>
13 #include <linux/compiler.h>
14 #include <linux/cache.h>
15 #include <linux/kmod.h>
16 #include <linux/elf.h>
17 #include <linux/stringify.h>
18 #include <linux/kobject.h>
19 #include <linux/moduleparam.h>
20 #include <asm/local.h>
21 
22 #include <asm/module.h>
23 
24 /* Not Yet Implemented */
25 #define MODULE_SUPPORTED_DEVICE(name)
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 struct module;
47 
48 struct module_attribute {
49         struct attribute attr;
50         ssize_t (*show)(struct module_attribute *, struct module *, char *);
51         ssize_t (*store)(struct module_attribute *, struct module *,
52 			 const char *, size_t count);
53 	void (*setup)(struct module *, const char *);
54 	int (*test)(struct module *);
55 	void (*free)(struct module *);
56 };
57 
58 struct module_kobject
59 {
60 	struct kobject kobj;
61 	struct module *mod;
62 };
63 
64 /* These are either module local, or the kernel's dummy ones. */
65 extern int init_module(void);
66 extern void cleanup_module(void);
67 
68 /* Archs provide a method of finding the correct exception table. */
69 struct exception_table_entry;
70 
71 const struct exception_table_entry *
72 search_extable(const struct exception_table_entry *first,
73 	       const struct exception_table_entry *last,
74 	       unsigned long value);
75 void sort_extable(struct exception_table_entry *start,
76 		  struct exception_table_entry *finish);
77 void sort_main_extable(void);
78 
79 extern struct subsystem module_subsys;
80 
81 #ifdef MODULE
82 #define MODULE_GENERIC_TABLE(gtype,name)			\
83 extern const struct gtype##_id __mod_##gtype##_table		\
84   __attribute__ ((unused, alias(__stringify(name))))
85 
86 extern struct module __this_module;
87 #define THIS_MODULE (&__this_module)
88 #else  /* !MODULE */
89 #define MODULE_GENERIC_TABLE(gtype,name)
90 #define THIS_MODULE ((struct module *)0)
91 #endif
92 
93 /* Generic info of form tag = "info" */
94 #define MODULE_INFO(tag, info) __MODULE_INFO(tag, tag, info)
95 
96 /* For userspace: you can also call me... */
97 #define MODULE_ALIAS(_alias) MODULE_INFO(alias, _alias)
98 
99 /*
100  * The following license idents are currently accepted as indicating free
101  * software modules
102  *
103  *	"GPL"				[GNU Public License v2 or later]
104  *	"GPL v2"			[GNU Public License v2]
105  *	"GPL and additional rights"	[GNU Public License v2 rights and more]
106  *	"Dual BSD/GPL"			[GNU Public License v2
107  *					 or BSD license choice]
108  *	"Dual MIT/GPL"			[GNU Public License v2
109  *					 or MIT license choice]
110  *	"Dual MPL/GPL"			[GNU Public License v2
111  *					 or Mozilla license choice]
112  *
113  * The following other idents are available
114  *
115  *	"Proprietary"			[Non free products]
116  *
117  * There are dual licensed components, but when running with Linux it is the
118  * GPL that is relevant so this is a non issue. Similarly LGPL linked with GPL
119  * is a GPL combined work.
120  *
121  * This exists for several reasons
122  * 1.	So modinfo can show license info for users wanting to vet their setup
123  *	is free
124  * 2.	So the community can ignore bug reports including proprietary modules
125  * 3.	So vendors can do likewise based on their own policies
126  */
127 #define MODULE_LICENSE(_license) MODULE_INFO(license, _license)
128 
129 /* Author, ideally of form NAME <EMAIL>[, NAME <EMAIL>]*[ and NAME <EMAIL>] */
130 #define MODULE_AUTHOR(_author) MODULE_INFO(author, _author)
131 
132 /* What your module does. */
133 #define MODULE_DESCRIPTION(_description) MODULE_INFO(description, _description)
134 
135 /* One for each parameter, describing how to use it.  Some files do
136    multiple of these per line, so can't just use MODULE_INFO. */
137 #define MODULE_PARM_DESC(_parm, desc) \
138 	__MODULE_INFO(parm, _parm, #_parm ":" desc)
139 
140 #define MODULE_DEVICE_TABLE(type,name)		\
141   MODULE_GENERIC_TABLE(type##_device,name)
142 
143 /* Version of form [<epoch>:]<version>[-<extra-version>].
144    Or for CVS/RCS ID version, everything but the number is stripped.
145   <epoch>: A (small) unsigned integer which allows you to start versions
146            anew. If not mentioned, it's zero.  eg. "2:1.0" is after
147 	   "1:2.0".
148   <version>: The <version> may contain only alphanumerics and the
149            character `.'.  Ordered by numeric sort for numeric parts,
150 	   ascii sort for ascii parts (as per RPM or DEB algorithm).
151   <extraversion>: Like <version>, but inserted for local
152            customizations, eg "rh3" or "rusty1".
153 
154   Using this automatically adds a checksum of the .c files and the
155   local headers in "srcversion".
156 */
157 #define MODULE_VERSION(_version) MODULE_INFO(version, _version)
158 
159 /* Given an address, look for it in the exception tables */
160 const struct exception_table_entry *search_exception_tables(unsigned long add);
161 
162 struct notifier_block;
163 
164 #ifdef CONFIG_MODULES
165 
166 /* Get/put a kernel symbol (calls must be symmetric) */
167 void *__symbol_get(const char *symbol);
168 void *__symbol_get_gpl(const char *symbol);
169 #define symbol_get(x) ((typeof(&x))(__symbol_get(MODULE_SYMBOL_PREFIX #x)))
170 
171 #ifndef __GENKSYMS__
172 #ifdef CONFIG_MODVERSIONS
173 /* Mark the CRC weak since genksyms apparently decides not to
174  * generate a checksums for some symbols */
175 #define __CRC_SYMBOL(sym, sec)					\
176 	extern void *__crc_##sym __attribute__((weak));		\
177 	static const unsigned long __kcrctab_##sym		\
178 	__attribute_used__					\
179 	__attribute__((section("__kcrctab" sec), unused))	\
180 	= (unsigned long) &__crc_##sym;
181 #else
182 #define __CRC_SYMBOL(sym, sec)
183 #endif
184 
185 /* For every exported symbol, place a struct in the __ksymtab section */
186 #define __EXPORT_SYMBOL(sym, sec)				\
187 	extern typeof(sym) sym;					\
188 	__CRC_SYMBOL(sym, sec)					\
189 	static const char __kstrtab_##sym[]			\
190 	__attribute__((section("__ksymtab_strings")))		\
191 	= MODULE_SYMBOL_PREFIX #sym;                    	\
192 	static const struct kernel_symbol __ksymtab_##sym	\
193 	__attribute_used__					\
194 	__attribute__((section("__ksymtab" sec), unused))	\
195 	= { (unsigned long)&sym, __kstrtab_##sym }
196 
197 #define EXPORT_SYMBOL(sym)					\
198 	__EXPORT_SYMBOL(sym, "")
199 
200 #define EXPORT_SYMBOL_GPL(sym)					\
201 	__EXPORT_SYMBOL(sym, "_gpl")
202 
203 #define EXPORT_SYMBOL_GPL_FUTURE(sym)				\
204 	__EXPORT_SYMBOL(sym, "_gpl_future")
205 
206 
207 #ifdef CONFIG_UNUSED_SYMBOLS
208 #define EXPORT_UNUSED_SYMBOL(sym) __EXPORT_SYMBOL(sym, "_unused")
209 #define EXPORT_UNUSED_SYMBOL_GPL(sym) __EXPORT_SYMBOL(sym, "_unused_gpl")
210 #else
211 #define EXPORT_UNUSED_SYMBOL(sym)
212 #define EXPORT_UNUSED_SYMBOL_GPL(sym)
213 #endif
214 
215 #endif
216 
217 struct module_ref
218 {
219 	local_t count;
220 } ____cacheline_aligned;
221 
222 enum module_state
223 {
224 	MODULE_STATE_LIVE,
225 	MODULE_STATE_COMING,
226 	MODULE_STATE_GOING,
227 };
228 
229 /* Similar stuff for section attributes. */
230 #define MODULE_SECT_NAME_LEN 32
231 struct module_sect_attr
232 {
233 	struct module_attribute mattr;
234 	char name[MODULE_SECT_NAME_LEN];
235 	unsigned long address;
236 };
237 
238 struct module_sect_attrs
239 {
240 	struct attribute_group grp;
241 	struct module_sect_attr attrs[0];
242 };
243 
244 struct module_param_attrs;
245 
246 struct module
247 {
248 	enum module_state state;
249 
250 	/* Member of list of modules */
251 	struct list_head list;
252 
253 	/* Unique handle for this module */
254 	char name[MODULE_NAME_LEN];
255 
256 	/* Sysfs stuff. */
257 	struct module_kobject mkobj;
258 	struct module_param_attrs *param_attrs;
259 	struct module_attribute *modinfo_attrs;
260 	const char *version;
261 	const char *srcversion;
262 
263 	/* Exported symbols */
264 	const struct kernel_symbol *syms;
265 	unsigned int num_syms;
266 	const unsigned long *crcs;
267 
268 	/* GPL-only exported symbols. */
269 	const struct kernel_symbol *gpl_syms;
270 	unsigned int num_gpl_syms;
271 	const unsigned long *gpl_crcs;
272 
273 	/* unused exported symbols. */
274 	const struct kernel_symbol *unused_syms;
275 	unsigned int num_unused_syms;
276 	const unsigned long *unused_crcs;
277 	/* GPL-only, unused exported symbols. */
278 	const struct kernel_symbol *unused_gpl_syms;
279 	unsigned int num_unused_gpl_syms;
280 	const unsigned long *unused_gpl_crcs;
281 
282 	/* symbols that will be GPL-only in the near future. */
283 	const struct kernel_symbol *gpl_future_syms;
284 	unsigned int num_gpl_future_syms;
285 	const unsigned long *gpl_future_crcs;
286 
287 	/* Exception table */
288 	unsigned int num_exentries;
289 	const struct exception_table_entry *extable;
290 
291 	/* Startup function. */
292 	int (*init)(void);
293 
294 	/* If this is non-NULL, vfree after init() returns */
295 	void *module_init;
296 
297 	/* Here is the actual code + data, vfree'd on unload. */
298 	void *module_core;
299 
300 	/* Here are the sizes of the init and core sections */
301 	unsigned long init_size, core_size;
302 
303 	/* The size of the executable code in each section.  */
304 	unsigned long init_text_size, core_text_size;
305 
306 	/* The handle returned from unwind_add_table. */
307 	void *unwind_info;
308 
309 	/* Arch-specific module values */
310 	struct mod_arch_specific arch;
311 
312 	/* Am I unsafe to unload? */
313 	int unsafe;
314 
315 	/* Am I GPL-compatible */
316 	int license_gplok;
317 
318 #ifdef CONFIG_MODULE_UNLOAD
319 	/* Reference counts */
320 	struct module_ref ref[NR_CPUS];
321 
322 	/* What modules depend on me? */
323 	struct list_head modules_which_use_me;
324 
325 	/* Who is waiting for us to be unloaded */
326 	struct task_struct *waiter;
327 
328 	/* Destruction function. */
329 	void (*exit)(void);
330 #endif
331 
332 #ifdef CONFIG_KALLSYMS
333 	/* We keep the symbol and string tables for kallsyms. */
334 	Elf_Sym *symtab;
335 	unsigned long num_symtab;
336 	char *strtab;
337 
338 	/* Section attributes */
339 	struct module_sect_attrs *sect_attrs;
340 #endif
341 
342 	/* Per-cpu data. */
343 	void *percpu;
344 
345 	/* The command line arguments (may be mangled).  People like
346 	   keeping pointers to this stuff */
347 	char *args;
348 };
349 
350 /* FIXME: It'd be nice to isolate modules during init, too, so they
351    aren't used before they (may) fail.  But presently too much code
352    (IDE & SCSI) require entry into the module during init.*/
module_is_live(struct module * mod)353 static inline int module_is_live(struct module *mod)
354 {
355 	return mod->state != MODULE_STATE_GOING;
356 }
357 
358 /* Is this address in a module? (second is with no locks, for oops) */
359 struct module *module_text_address(unsigned long addr);
360 struct module *__module_text_address(unsigned long addr);
361 int is_module_address(unsigned long addr);
362 
363 /* Returns module and fills in value, defined and namebuf, or NULL if
364    symnum out of range. */
365 struct module *module_get_kallsym(unsigned int symnum, unsigned long *value,
366 				char *type, char *name, size_t namelen);
367 
368 /* Look for this name: can be of form module:name. */
369 unsigned long module_kallsyms_lookup_name(const char *name);
370 
371 int is_exported(const char *name, const struct module *mod);
372 
373 extern void __module_put_and_exit(struct module *mod, long code)
374 	__attribute__((noreturn));
375 #define module_put_and_exit(code) __module_put_and_exit(THIS_MODULE, code);
376 
377 #ifdef CONFIG_MODULE_UNLOAD
378 unsigned int module_refcount(struct module *mod);
379 void __symbol_put(const char *symbol);
380 #define symbol_put(x) __symbol_put(MODULE_SYMBOL_PREFIX #x)
381 void symbol_put_addr(void *addr);
382 
383 /* Sometimes we know we already have a refcount, and it's easier not
384    to handle the error case (which only happens with rmmod --wait). */
__module_get(struct module * module)385 static inline void __module_get(struct module *module)
386 {
387 	if (module) {
388 		BUG_ON(module_refcount(module) == 0);
389 		local_inc(&module->ref[get_cpu()].count);
390 		put_cpu();
391 	}
392 }
393 
try_module_get(struct module * module)394 static inline int try_module_get(struct module *module)
395 {
396 	int ret = 1;
397 
398 	if (module) {
399 		unsigned int cpu = get_cpu();
400 		if (likely(module_is_live(module)))
401 			local_inc(&module->ref[cpu].count);
402 		else
403 			ret = 0;
404 		put_cpu();
405 	}
406 	return ret;
407 }
408 
module_put(struct module * module)409 static inline void module_put(struct module *module)
410 {
411 	if (module) {
412 		unsigned int cpu = get_cpu();
413 		local_dec(&module->ref[cpu].count);
414 		/* Maybe they're waiting for us to drop reference? */
415 		if (unlikely(!module_is_live(module)))
416 			wake_up_process(module->waiter);
417 		put_cpu();
418 	}
419 }
420 
421 #else /*!CONFIG_MODULE_UNLOAD*/
try_module_get(struct module * module)422 static inline int try_module_get(struct module *module)
423 {
424 	return !module || module_is_live(module);
425 }
module_put(struct module * module)426 static inline void module_put(struct module *module)
427 {
428 }
__module_get(struct module * module)429 static inline void __module_get(struct module *module)
430 {
431 }
432 #define symbol_put(x) do { } while(0)
433 #define symbol_put_addr(p) do { } while(0)
434 
435 #endif /* CONFIG_MODULE_UNLOAD */
436 
437 /* This is a #define so the string doesn't get put in every .o file */
438 #define module_name(mod)			\
439 ({						\
440 	struct module *__mod = (mod);		\
441 	__mod ? __mod->name : "kernel";		\
442 })
443 
444 #define __unsafe(mod)							     \
445 do {									     \
446 	if (mod && !(mod)->unsafe) {					     \
447 		printk(KERN_WARNING					     \
448 		       "Module %s cannot be unloaded due to unsafe usage in" \
449 		       " %s:%u\n", (mod)->name, __FILE__, __LINE__);	     \
450 		(mod)->unsafe = 1;					     \
451 	}								     \
452 } while(0)
453 
454 /* For kallsyms to ask for address resolution.  NULL means not found. */
455 const char *module_address_lookup(unsigned long addr,
456 				  unsigned long *symbolsize,
457 				  unsigned long *offset,
458 				  char **modname);
459 
460 /* For extable.c to search modules' exception tables. */
461 const struct exception_table_entry *search_module_extables(unsigned long addr);
462 
463 int register_module_notifier(struct notifier_block * nb);
464 int unregister_module_notifier(struct notifier_block * nb);
465 
466 extern void print_modules(void);
467 
468 struct device_driver;
469 void module_add_driver(struct module *, struct device_driver *);
470 void module_remove_driver(struct device_driver *);
471 
472 #else /* !CONFIG_MODULES... */
473 #define EXPORT_SYMBOL(sym)
474 #define EXPORT_SYMBOL_GPL(sym)
475 #define EXPORT_SYMBOL_GPL_FUTURE(sym)
476 #define EXPORT_UNUSED_SYMBOL(sym)
477 #define EXPORT_UNUSED_SYMBOL_GPL(sym)
478 
479 /* Given an address, look for it in the exception tables. */
480 static inline const struct exception_table_entry *
search_module_extables(unsigned long addr)481 search_module_extables(unsigned long addr)
482 {
483 	return NULL;
484 }
485 
486 /* Is this address in a module? */
module_text_address(unsigned long addr)487 static inline struct module *module_text_address(unsigned long addr)
488 {
489 	return NULL;
490 }
491 
492 /* Is this address in a module? (don't take a lock, we're oopsing) */
__module_text_address(unsigned long addr)493 static inline struct module *__module_text_address(unsigned long addr)
494 {
495 	return NULL;
496 }
497 
is_module_address(unsigned long addr)498 static inline int is_module_address(unsigned long addr)
499 {
500 	return 0;
501 }
502 
503 /* Get/put a kernel symbol (calls should be symmetric) */
504 #define symbol_get(x) ({ extern typeof(x) x __attribute__((weak)); &(x); })
505 #define symbol_put(x) do { } while(0)
506 #define symbol_put_addr(x) do { } while(0)
507 
__module_get(struct module * module)508 static inline void __module_get(struct module *module)
509 {
510 }
511 
try_module_get(struct module * module)512 static inline int try_module_get(struct module *module)
513 {
514 	return 1;
515 }
516 
module_put(struct module * module)517 static inline void module_put(struct module *module)
518 {
519 }
520 
521 #define module_name(mod) "kernel"
522 
523 #define __unsafe(mod)
524 
525 /* For kallsyms to ask for address resolution.  NULL means not found. */
module_address_lookup(unsigned long addr,unsigned long * symbolsize,unsigned long * offset,char ** modname)526 static inline const char *module_address_lookup(unsigned long addr,
527 						unsigned long *symbolsize,
528 						unsigned long *offset,
529 						char **modname)
530 {
531 	return NULL;
532 }
533 
module_get_kallsym(unsigned int symnum,unsigned long * value,char * type,char * name,size_t namelen)534 static inline struct module *module_get_kallsym(unsigned int symnum,
535 						unsigned long *value,
536 						char *type, char *name,
537 						size_t namelen)
538 {
539 	return NULL;
540 }
541 
module_kallsyms_lookup_name(const char * name)542 static inline unsigned long module_kallsyms_lookup_name(const char *name)
543 {
544 	return 0;
545 }
546 
is_exported(const char * name,const struct module * mod)547 static inline int is_exported(const char *name, const struct module *mod)
548 {
549 	return 0;
550 }
551 
register_module_notifier(struct notifier_block * nb)552 static inline int register_module_notifier(struct notifier_block * nb)
553 {
554 	/* no events will happen anyway, so this can always succeed */
555 	return 0;
556 }
557 
unregister_module_notifier(struct notifier_block * nb)558 static inline int unregister_module_notifier(struct notifier_block * nb)
559 {
560 	return 0;
561 }
562 
563 #define module_put_and_exit(code) do_exit(code)
564 
print_modules(void)565 static inline void print_modules(void)
566 {
567 }
568 
569 struct device_driver;
570 struct module;
571 
module_add_driver(struct module * module,struct device_driver * driver)572 static inline void module_add_driver(struct module *module, struct device_driver *driver)
573 {
574 }
575 
module_remove_driver(struct device_driver * driver)576 static inline void module_remove_driver(struct device_driver *driver)
577 {
578 }
579 
580 #endif /* CONFIG_MODULES */
581 
582 #define symbol_request(x) try_then_request_module(symbol_get(x), "symbol:" #x)
583 
584 /* BELOW HERE ALL THESE ARE OBSOLETE AND WILL VANISH */
585 
586 #define __MODULE_STRING(x) __stringify(x)
587 
588 #endif /* _LINUX_MODULE_H */
589