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[linux-2.6/next.git] / include / linux / module.h
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1 #ifndef _LINUX_MODULE_H
2 #define _LINUX_MODULE_H
3 /*
4 * Dynamic loading of modules into the kernel.
6 * Rewritten by Richard Henderson <rth@tamu.edu> Dec 1996
7 * Rewritten again by Rusty Russell, 2002
8 */
9 #include <linux/list.h>
10 #include <linux/stat.h>
11 #include <linux/compiler.h>
12 #include <linux/cache.h>
13 #include <linux/kmod.h>
14 #include <linux/elf.h>
15 #include <linux/stringify.h>
16 #include <linux/kobject.h>
17 #include <linux/moduleparam.h>
18 #include <linux/tracepoint.h>
20 #include <linux/percpu.h>
21 #include <asm/module.h>
23 #include <trace/events/module.h>
25 /* Not Yet Implemented */
26 #define MODULE_SUPPORTED_DEVICE(name)
28 /* Some toolchains use a `_' prefix for all user symbols. */
29 #ifdef CONFIG_SYMBOL_PREFIX
30 #define MODULE_SYMBOL_PREFIX CONFIG_SYMBOL_PREFIX
31 #else
32 #define MODULE_SYMBOL_PREFIX ""
33 #endif
35 #define MODULE_NAME_LEN MAX_PARAM_PREFIX_LEN
37 struct kernel_symbol
39 unsigned long value;
40 const char *name;
43 struct modversion_info
45 unsigned long crc;
46 char name[MODULE_NAME_LEN];
49 struct module;
51 struct module_attribute {
52 struct attribute attr;
53 ssize_t (*show)(struct module_attribute *, struct module *, char *);
54 ssize_t (*store)(struct module_attribute *, struct module *,
55 const char *, size_t count);
56 void (*setup)(struct module *, const char *);
57 int (*test)(struct module *);
58 void (*free)(struct module *);
61 struct module_kobject
63 struct kobject kobj;
64 struct module *mod;
65 struct kobject *drivers_dir;
66 struct module_param_attrs *mp;
69 /* These are either module local, or the kernel's dummy ones. */
70 extern int init_module(void);
71 extern void cleanup_module(void);
73 /* Archs provide a method of finding the correct exception table. */
74 struct exception_table_entry;
76 const struct exception_table_entry *
77 search_extable(const struct exception_table_entry *first,
78 const struct exception_table_entry *last,
79 unsigned long value);
80 void sort_extable(struct exception_table_entry *start,
81 struct exception_table_entry *finish);
82 void sort_main_extable(void);
83 void trim_init_extable(struct module *m);
85 #ifdef MODULE
86 #define MODULE_GENERIC_TABLE(gtype,name) \
87 extern const struct gtype##_id __mod_##gtype##_table \
88 __attribute__ ((unused, alias(__stringify(name))))
90 extern struct module __this_module;
91 #define THIS_MODULE (&__this_module)
92 #else /* !MODULE */
93 #define MODULE_GENERIC_TABLE(gtype,name)
94 #define THIS_MODULE ((struct module *)0)
95 #endif
97 /* Generic info of form tag = "info" */
98 #define MODULE_INFO(tag, info) __MODULE_INFO(tag, tag, info)
100 /* For userspace: you can also call me... */
101 #define MODULE_ALIAS(_alias) MODULE_INFO(alias, _alias)
104 * The following license idents are currently accepted as indicating free
105 * software modules
107 * "GPL" [GNU Public License v2 or later]
108 * "GPL v2" [GNU Public License v2]
109 * "GPL and additional rights" [GNU Public License v2 rights and more]
110 * "Dual BSD/GPL" [GNU Public License v2
111 * or BSD license choice]
112 * "Dual MIT/GPL" [GNU Public License v2
113 * or MIT license choice]
114 * "Dual MPL/GPL" [GNU Public License v2
115 * or Mozilla license choice]
117 * The following other idents are available
119 * "Proprietary" [Non free products]
121 * There are dual licensed components, but when running with Linux it is the
122 * GPL that is relevant so this is a non issue. Similarly LGPL linked with GPL
123 * is a GPL combined work.
125 * This exists for several reasons
126 * 1. So modinfo can show license info for users wanting to vet their setup
127 * is free
128 * 2. So the community can ignore bug reports including proprietary modules
129 * 3. So vendors can do likewise based on their own policies
131 #define MODULE_LICENSE(_license) MODULE_INFO(license, _license)
134 * Author(s), use "Name <email>" or just "Name", for multiple
135 * authors use multiple MODULE_AUTHOR() statements/lines.
137 #define MODULE_AUTHOR(_author) MODULE_INFO(author, _author)
139 /* What your module does. */
140 #define MODULE_DESCRIPTION(_description) MODULE_INFO(description, _description)
142 /* One for each parameter, describing how to use it. Some files do
143 multiple of these per line, so can't just use MODULE_INFO. */
144 #define MODULE_PARM_DESC(_parm, desc) \
145 __MODULE_INFO(parm, _parm, #_parm ":" desc)
147 #define MODULE_DEVICE_TABLE(type,name) \
148 MODULE_GENERIC_TABLE(type##_device,name)
150 /* Version of form [<epoch>:]<version>[-<extra-version>].
151 Or for CVS/RCS ID version, everything but the number is stripped.
152 <epoch>: A (small) unsigned integer which allows you to start versions
153 anew. If not mentioned, it's zero. eg. "2:1.0" is after
154 "1:2.0".
155 <version>: The <version> may contain only alphanumerics and the
156 character `.'. Ordered by numeric sort for numeric parts,
157 ascii sort for ascii parts (as per RPM or DEB algorithm).
158 <extraversion>: Like <version>, but inserted for local
159 customizations, eg "rh3" or "rusty1".
161 Using this automatically adds a checksum of the .c files and the
162 local headers in "srcversion".
164 #define MODULE_VERSION(_version) MODULE_INFO(version, _version)
166 /* Optional firmware file (or files) needed by the module
167 * format is simply firmware file name. Multiple firmware
168 * files require multiple MODULE_FIRMWARE() specifiers */
169 #define MODULE_FIRMWARE(_firmware) MODULE_INFO(firmware, _firmware)
171 /* Given an address, look for it in the exception tables */
172 const struct exception_table_entry *search_exception_tables(unsigned long add);
174 struct notifier_block;
176 #ifdef CONFIG_MODULES
178 extern int modules_disabled; /* for sysctl */
179 /* Get/put a kernel symbol (calls must be symmetric) */
180 void *__symbol_get(const char *symbol);
181 void *__symbol_get_gpl(const char *symbol);
182 #define symbol_get(x) ((typeof(&x))(__symbol_get(MODULE_SYMBOL_PREFIX #x)))
184 /* modules using other modules: kdb wants to see this. */
185 struct module_use {
186 struct list_head source_list;
187 struct list_head target_list;
188 struct module *source, *target;
191 #ifndef __GENKSYMS__
192 #ifdef CONFIG_MODVERSIONS
193 /* Mark the CRC weak since genksyms apparently decides not to
194 * generate a checksums for some symbols */
195 #define __CRC_SYMBOL(sym, sec) \
196 extern void *__crc_##sym __attribute__((weak)); \
197 static const unsigned long __kcrctab_##sym \
198 __used \
199 __attribute__((section("__kcrctab" sec), unused)) \
200 = (unsigned long) &__crc_##sym;
201 #else
202 #define __CRC_SYMBOL(sym, sec)
203 #endif
205 /* For every exported symbol, place a struct in the __ksymtab section */
206 #define __EXPORT_SYMBOL(sym, sec) \
207 extern typeof(sym) sym; \
208 __CRC_SYMBOL(sym, sec) \
209 static const char __kstrtab_##sym[] \
210 __attribute__((section("__ksymtab_strings"), aligned(1))) \
211 = MODULE_SYMBOL_PREFIX #sym; \
212 static const struct kernel_symbol __ksymtab_##sym \
213 __used \
214 __attribute__((section("__ksymtab" sec), unused)) \
215 = { (unsigned long)&sym, __kstrtab_##sym }
217 #define EXPORT_SYMBOL(sym) \
218 __EXPORT_SYMBOL(sym, "")
220 #define EXPORT_SYMBOL_GPL(sym) \
221 __EXPORT_SYMBOL(sym, "_gpl")
223 #define EXPORT_SYMBOL_GPL_FUTURE(sym) \
224 __EXPORT_SYMBOL(sym, "_gpl_future")
227 #ifdef CONFIG_UNUSED_SYMBOLS
228 #define EXPORT_UNUSED_SYMBOL(sym) __EXPORT_SYMBOL(sym, "_unused")
229 #define EXPORT_UNUSED_SYMBOL_GPL(sym) __EXPORT_SYMBOL(sym, "_unused_gpl")
230 #else
231 #define EXPORT_UNUSED_SYMBOL(sym)
232 #define EXPORT_UNUSED_SYMBOL_GPL(sym)
233 #endif
235 #endif
237 enum module_state
239 MODULE_STATE_LIVE,
240 MODULE_STATE_COMING,
241 MODULE_STATE_GOING,
244 struct module
246 enum module_state state;
248 /* Member of list of modules */
249 struct list_head list;
251 /* Unique handle for this module */
252 char name[MODULE_NAME_LEN];
254 /* Sysfs stuff. */
255 struct module_kobject mkobj;
256 struct module_attribute *modinfo_attrs;
257 const char *version;
258 const char *srcversion;
259 struct kobject *holders_dir;
261 /* Exported symbols */
262 const struct kernel_symbol *syms;
263 const unsigned long *crcs;
264 unsigned int num_syms;
266 /* Kernel parameters. */
267 struct kernel_param *kp;
268 unsigned int num_kp;
270 /* GPL-only exported symbols. */
271 unsigned int num_gpl_syms;
272 const struct kernel_symbol *gpl_syms;
273 const unsigned long *gpl_crcs;
275 #ifdef CONFIG_UNUSED_SYMBOLS
276 /* unused exported symbols. */
277 const struct kernel_symbol *unused_syms;
278 const unsigned long *unused_crcs;
279 unsigned int num_unused_syms;
281 /* GPL-only, unused exported symbols. */
282 unsigned int num_unused_gpl_syms;
283 const struct kernel_symbol *unused_gpl_syms;
284 const unsigned long *unused_gpl_crcs;
285 #endif
287 /* symbols that will be GPL-only in the near future. */
288 const struct kernel_symbol *gpl_future_syms;
289 const unsigned long *gpl_future_crcs;
290 unsigned int num_gpl_future_syms;
292 /* Exception table */
293 unsigned int num_exentries;
294 struct exception_table_entry *extable;
296 /* Startup function. */
297 int (*init)(void);
299 /* If this is non-NULL, vfree after init() returns */
300 void *module_init;
302 /* Here is the actual code + data, vfree'd on unload. */
303 void *module_core;
305 /* Here are the sizes of the init and core sections */
306 unsigned int init_size, core_size;
308 /* The size of the executable code in each section. */
309 unsigned int init_text_size, core_text_size;
311 /* Arch-specific module values */
312 struct mod_arch_specific arch;
314 unsigned int taints; /* same bits as kernel:tainted */
316 #ifdef CONFIG_GENERIC_BUG
317 /* Support for BUG */
318 unsigned num_bugs;
319 struct list_head bug_list;
320 struct bug_entry *bug_table;
321 #endif
323 #ifdef CONFIG_KALLSYMS
325 * We keep the symbol and string tables for kallsyms.
326 * The core_* fields below are temporary, loader-only (they
327 * could really be discarded after module init).
329 Elf_Sym *symtab, *core_symtab;
330 unsigned int num_symtab, core_num_syms;
331 char *strtab, *core_strtab;
333 /* Section attributes */
334 struct module_sect_attrs *sect_attrs;
336 /* Notes attributes */
337 struct module_notes_attrs *notes_attrs;
338 #endif
340 #ifdef CONFIG_SMP
341 /* Per-cpu data. */
342 void __percpu *percpu;
343 unsigned int percpu_size;
344 #endif
346 /* The command line arguments (may be mangled). People like
347 keeping pointers to this stuff */
348 char *args;
349 #ifdef CONFIG_TRACEPOINTS
350 struct tracepoint *tracepoints;
351 unsigned int num_tracepoints;
352 #endif
354 #ifdef CONFIG_TRACING
355 const char **trace_bprintk_fmt_start;
356 unsigned int num_trace_bprintk_fmt;
357 #endif
358 #ifdef CONFIG_EVENT_TRACING
359 struct ftrace_event_call *trace_events;
360 unsigned int num_trace_events;
361 #endif
362 #ifdef CONFIG_FTRACE_MCOUNT_RECORD
363 unsigned long *ftrace_callsites;
364 unsigned int num_ftrace_callsites;
365 #endif
367 #ifdef CONFIG_MODULE_UNLOAD
368 /* What modules depend on me? */
369 struct list_head source_list;
370 /* What modules do I depend on? */
371 struct list_head target_list;
373 /* Who is waiting for us to be unloaded */
374 struct task_struct *waiter;
376 /* Destruction function. */
377 void (*exit)(void);
379 struct module_ref {
380 unsigned int incs;
381 unsigned int decs;
382 } __percpu *refptr;
383 #endif
385 #ifdef CONFIG_CONSTRUCTORS
386 /* Constructor functions. */
387 ctor_fn_t *ctors;
388 unsigned int num_ctors;
389 #endif
391 #ifndef MODULE_ARCH_INIT
392 #define MODULE_ARCH_INIT {}
393 #endif
395 extern struct mutex module_mutex;
397 /* FIXME: It'd be nice to isolate modules during init, too, so they
398 aren't used before they (may) fail. But presently too much code
399 (IDE & SCSI) require entry into the module during init.*/
400 static inline int module_is_live(struct module *mod)
402 return mod->state != MODULE_STATE_GOING;
405 struct module *__module_text_address(unsigned long addr);
406 struct module *__module_address(unsigned long addr);
407 bool is_module_address(unsigned long addr);
408 bool is_module_percpu_address(unsigned long addr);
409 bool is_module_text_address(unsigned long addr);
411 static inline int within_module_core(unsigned long addr, struct module *mod)
413 return (unsigned long)mod->module_core <= addr &&
414 addr < (unsigned long)mod->module_core + mod->core_size;
417 static inline int within_module_init(unsigned long addr, struct module *mod)
419 return (unsigned long)mod->module_init <= addr &&
420 addr < (unsigned long)mod->module_init + mod->init_size;
423 /* Search for module by name: must hold module_mutex. */
424 struct module *find_module(const char *name);
426 struct symsearch {
427 const struct kernel_symbol *start, *stop;
428 const unsigned long *crcs;
429 enum {
430 NOT_GPL_ONLY,
431 GPL_ONLY,
432 WILL_BE_GPL_ONLY,
433 } licence;
434 bool unused;
437 /* Search for an exported symbol by name. */
438 const struct kernel_symbol *find_symbol(const char *name,
439 struct module **owner,
440 const unsigned long **crc,
441 bool gplok,
442 bool warn);
444 /* Walk the exported symbol table */
445 bool each_symbol(bool (*fn)(const struct symsearch *arr, struct module *owner,
446 unsigned int symnum, void *data), void *data);
448 /* Returns 0 and fills in value, defined and namebuf, or -ERANGE if
449 symnum out of range. */
450 int module_get_kallsym(unsigned int symnum, unsigned long *value, char *type,
451 char *name, char *module_name, int *exported);
453 /* Look for this name: can be of form module:name. */
454 unsigned long module_kallsyms_lookup_name(const char *name);
456 int module_kallsyms_on_each_symbol(int (*fn)(void *, const char *,
457 struct module *, unsigned long),
458 void *data);
460 extern void __module_put_and_exit(struct module *mod, long code)
461 __attribute__((noreturn));
462 #define module_put_and_exit(code) __module_put_and_exit(THIS_MODULE, code);
464 #ifdef CONFIG_MODULE_UNLOAD
465 unsigned int module_refcount(struct module *mod);
466 void __symbol_put(const char *symbol);
467 #define symbol_put(x) __symbol_put(MODULE_SYMBOL_PREFIX #x)
468 void symbol_put_addr(void *addr);
470 /* Sometimes we know we already have a refcount, and it's easier not
471 to handle the error case (which only happens with rmmod --wait). */
472 static inline void __module_get(struct module *module)
474 if (module) {
475 preempt_disable();
476 __this_cpu_inc(module->refptr->incs);
477 trace_module_get(module, _THIS_IP_);
478 preempt_enable();
482 static inline int try_module_get(struct module *module)
484 int ret = 1;
486 if (module) {
487 preempt_disable();
489 if (likely(module_is_live(module))) {
490 __this_cpu_inc(module->refptr->incs);
491 trace_module_get(module, _THIS_IP_);
492 } else
493 ret = 0;
495 preempt_enable();
497 return ret;
500 extern void module_put(struct module *module);
502 #else /*!CONFIG_MODULE_UNLOAD*/
503 static inline int try_module_get(struct module *module)
505 return !module || module_is_live(module);
507 static inline void module_put(struct module *module)
510 static inline void __module_get(struct module *module)
513 #define symbol_put(x) do { } while(0)
514 #define symbol_put_addr(p) do { } while(0)
516 #endif /* CONFIG_MODULE_UNLOAD */
517 int use_module(struct module *a, struct module *b);
519 /* This is a #define so the string doesn't get put in every .o file */
520 #define module_name(mod) \
521 ({ \
522 struct module *__mod = (mod); \
523 __mod ? __mod->name : "kernel"; \
526 /* For kallsyms to ask for address resolution. namebuf should be at
527 * least KSYM_NAME_LEN long: a pointer to namebuf is returned if
528 * found, otherwise NULL. */
529 const char *module_address_lookup(unsigned long addr,
530 unsigned long *symbolsize,
531 unsigned long *offset,
532 char **modname,
533 char *namebuf);
534 int lookup_module_symbol_name(unsigned long addr, char *symname);
535 int lookup_module_symbol_attrs(unsigned long addr, unsigned long *size, unsigned long *offset, char *modname, char *name);
537 /* For extable.c to search modules' exception tables. */
538 const struct exception_table_entry *search_module_extables(unsigned long addr);
540 int register_module_notifier(struct notifier_block * nb);
541 int unregister_module_notifier(struct notifier_block * nb);
543 extern void print_modules(void);
545 extern void module_update_tracepoints(void);
546 extern int module_get_iter_tracepoints(struct tracepoint_iter *iter);
548 #else /* !CONFIG_MODULES... */
549 #define EXPORT_SYMBOL(sym)
550 #define EXPORT_SYMBOL_GPL(sym)
551 #define EXPORT_SYMBOL_GPL_FUTURE(sym)
552 #define EXPORT_UNUSED_SYMBOL(sym)
553 #define EXPORT_UNUSED_SYMBOL_GPL(sym)
555 /* Given an address, look for it in the exception tables. */
556 static inline const struct exception_table_entry *
557 search_module_extables(unsigned long addr)
559 return NULL;
562 static inline struct module *__module_address(unsigned long addr)
564 return NULL;
567 static inline struct module *__module_text_address(unsigned long addr)
569 return NULL;
572 static inline bool is_module_address(unsigned long addr)
574 return false;
577 static inline bool is_module_percpu_address(unsigned long addr)
579 return false;
582 static inline bool is_module_text_address(unsigned long addr)
584 return false;
587 /* Get/put a kernel symbol (calls should be symmetric) */
588 #define symbol_get(x) ({ extern typeof(x) x __attribute__((weak)); &(x); })
589 #define symbol_put(x) do { } while(0)
590 #define symbol_put_addr(x) do { } while(0)
592 static inline void __module_get(struct module *module)
596 static inline int try_module_get(struct module *module)
598 return 1;
601 static inline void module_put(struct module *module)
605 #define module_name(mod) "kernel"
607 /* For kallsyms to ask for address resolution. NULL means not found. */
608 static inline const char *module_address_lookup(unsigned long addr,
609 unsigned long *symbolsize,
610 unsigned long *offset,
611 char **modname,
612 char *namebuf)
614 return NULL;
617 static inline int lookup_module_symbol_name(unsigned long addr, char *symname)
619 return -ERANGE;
622 static inline int lookup_module_symbol_attrs(unsigned long addr, unsigned long *size, unsigned long *offset, char *modname, char *name)
624 return -ERANGE;
627 static inline int module_get_kallsym(unsigned int symnum, unsigned long *value,
628 char *type, char *name,
629 char *module_name, int *exported)
631 return -ERANGE;
634 static inline unsigned long module_kallsyms_lookup_name(const char *name)
636 return 0;
639 static inline int module_kallsyms_on_each_symbol(int (*fn)(void *, const char *,
640 struct module *,
641 unsigned long),
642 void *data)
644 return 0;
647 static inline int register_module_notifier(struct notifier_block * nb)
649 /* no events will happen anyway, so this can always succeed */
650 return 0;
653 static inline int unregister_module_notifier(struct notifier_block * nb)
655 return 0;
658 #define module_put_and_exit(code) do_exit(code)
660 static inline void print_modules(void)
664 static inline void module_update_tracepoints(void)
668 static inline int module_get_iter_tracepoints(struct tracepoint_iter *iter)
670 return 0;
673 #endif /* CONFIG_MODULES */
675 #ifdef CONFIG_SYSFS
676 extern struct kset *module_kset;
677 extern struct kobj_type module_ktype;
678 extern int module_sysfs_initialized;
679 #endif /* CONFIG_SYSFS */
681 #define symbol_request(x) try_then_request_module(symbol_get(x), "symbol:" #x)
683 /* BELOW HERE ALL THESE ARE OBSOLETE AND WILL VANISH */
685 #define __MODULE_STRING(x) __stringify(x)
688 #ifdef CONFIG_GENERIC_BUG
689 int module_bug_finalize(const Elf_Ehdr *, const Elf_Shdr *,
690 struct module *);
691 void module_bug_cleanup(struct module *);
693 #else /* !CONFIG_GENERIC_BUG */
695 static inline int module_bug_finalize(const Elf_Ehdr *hdr,
696 const Elf_Shdr *sechdrs,
697 struct module *mod)
699 return 0;
701 static inline void module_bug_cleanup(struct module *mod) {}
702 #endif /* CONFIG_GENERIC_BUG */
704 #endif /* _LINUX_MODULE_H */