Merge branch 'docs-next' of git://git.lwn.net/linux-2.6
[linux-2.6/next.git] / include / linux / module.h
blob482efc865acf272994b4de7906a8d403a1c1454a
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 <asm/local.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 uses a `_' prefix for all user symbols */
29 #ifndef MODULE_SYMBOL_PREFIX
30 #define MODULE_SYMBOL_PREFIX ""
31 #endif
33 #define MODULE_NAME_LEN MAX_PARAM_PREFIX_LEN
35 struct kernel_symbol
37 unsigned long value;
38 const char *name;
41 struct modversion_info
43 unsigned long crc;
44 char name[MODULE_NAME_LEN];
47 struct module;
49 struct module_attribute {
50 struct attribute attr;
51 ssize_t (*show)(struct module_attribute *, struct module *, char *);
52 ssize_t (*store)(struct module_attribute *, struct module *,
53 const char *, size_t count);
54 void (*setup)(struct module *, const char *);
55 int (*test)(struct module *);
56 void (*free)(struct module *);
59 struct module_kobject
61 struct kobject kobj;
62 struct module *mod;
63 struct kobject *drivers_dir;
64 struct module_param_attrs *mp;
67 /* These are either module local, or the kernel's dummy ones. */
68 extern int init_module(void);
69 extern void cleanup_module(void);
71 /* Archs provide a method of finding the correct exception table. */
72 struct exception_table_entry;
74 const struct exception_table_entry *
75 search_extable(const struct exception_table_entry *first,
76 const struct exception_table_entry *last,
77 unsigned long value);
78 void sort_extable(struct exception_table_entry *start,
79 struct exception_table_entry *finish);
80 void sort_main_extable(void);
81 void trim_init_extable(struct module *m);
83 #ifdef MODULE
84 #define MODULE_GENERIC_TABLE(gtype,name) \
85 extern const struct gtype##_id __mod_##gtype##_table \
86 __attribute__ ((unused, alias(__stringify(name))))
88 extern struct module __this_module;
89 #define THIS_MODULE (&__this_module)
90 #else /* !MODULE */
91 #define MODULE_GENERIC_TABLE(gtype,name)
92 #define THIS_MODULE ((struct module *)0)
93 #endif
95 /* Generic info of form tag = "info" */
96 #define MODULE_INFO(tag, info) __MODULE_INFO(tag, tag, info)
98 /* For userspace: you can also call me... */
99 #define MODULE_ALIAS(_alias) MODULE_INFO(alias, _alias)
102 * The following license idents are currently accepted as indicating free
103 * software modules
105 * "GPL" [GNU Public License v2 or later]
106 * "GPL v2" [GNU Public License v2]
107 * "GPL and additional rights" [GNU Public License v2 rights and more]
108 * "Dual BSD/GPL" [GNU Public License v2
109 * or BSD license choice]
110 * "Dual MIT/GPL" [GNU Public License v2
111 * or MIT license choice]
112 * "Dual MPL/GPL" [GNU Public License v2
113 * or Mozilla license choice]
115 * The following other idents are available
117 * "Proprietary" [Non free products]
119 * There are dual licensed components, but when running with Linux it is the
120 * GPL that is relevant so this is a non issue. Similarly LGPL linked with GPL
121 * is a GPL combined work.
123 * This exists for several reasons
124 * 1. So modinfo can show license info for users wanting to vet their setup
125 * is free
126 * 2. So the community can ignore bug reports including proprietary modules
127 * 3. So vendors can do likewise based on their own policies
129 #define MODULE_LICENSE(_license) MODULE_INFO(license, _license)
132 * Author(s), use "Name <email>" or just "Name", for multiple
133 * authors use multiple MODULE_AUTHOR() statements/lines.
135 #define MODULE_AUTHOR(_author) MODULE_INFO(author, _author)
137 /* What your module does. */
138 #define MODULE_DESCRIPTION(_description) MODULE_INFO(description, _description)
140 /* One for each parameter, describing how to use it. Some files do
141 multiple of these per line, so can't just use MODULE_INFO. */
142 #define MODULE_PARM_DESC(_parm, desc) \
143 __MODULE_INFO(parm, _parm, #_parm ":" desc)
145 #define MODULE_DEVICE_TABLE(type,name) \
146 MODULE_GENERIC_TABLE(type##_device,name)
148 /* Version of form [<epoch>:]<version>[-<extra-version>].
149 Or for CVS/RCS ID version, everything but the number is stripped.
150 <epoch>: A (small) unsigned integer which allows you to start versions
151 anew. If not mentioned, it's zero. eg. "2:1.0" is after
152 "1:2.0".
153 <version>: The <version> may contain only alphanumerics and the
154 character `.'. Ordered by numeric sort for numeric parts,
155 ascii sort for ascii parts (as per RPM or DEB algorithm).
156 <extraversion>: Like <version>, but inserted for local
157 customizations, eg "rh3" or "rusty1".
159 Using this automatically adds a checksum of the .c files and the
160 local headers in "srcversion".
162 #define MODULE_VERSION(_version) MODULE_INFO(version, _version)
164 /* Optional firmware file (or files) needed by the module
165 * format is simply firmware file name. Multiple firmware
166 * files require multiple MODULE_FIRMWARE() specifiers */
167 #define MODULE_FIRMWARE(_firmware) MODULE_INFO(firmware, _firmware)
169 /* Given an address, look for it in the exception tables */
170 const struct exception_table_entry *search_exception_tables(unsigned long add);
172 struct notifier_block;
174 #ifdef CONFIG_MODULES
176 /* Get/put a kernel symbol (calls must be symmetric) */
177 void *__symbol_get(const char *symbol);
178 void *__symbol_get_gpl(const char *symbol);
179 #define symbol_get(x) ((typeof(&x))(__symbol_get(MODULE_SYMBOL_PREFIX #x)))
181 #ifndef __GENKSYMS__
182 #ifdef CONFIG_MODVERSIONS
183 /* Mark the CRC weak since genksyms apparently decides not to
184 * generate a checksums for some symbols */
185 #define __CRC_SYMBOL(sym, sec) \
186 extern void *__crc_##sym __attribute__((weak)); \
187 static const unsigned long __kcrctab_##sym \
188 __used \
189 __attribute__((section("__kcrctab" sec), unused)) \
190 = (unsigned long) &__crc_##sym;
191 #else
192 #define __CRC_SYMBOL(sym, sec)
193 #endif
195 /* For every exported symbol, place a struct in the __ksymtab section */
196 #define __EXPORT_SYMBOL(sym, sec) \
197 extern typeof(sym) sym; \
198 __CRC_SYMBOL(sym, sec) \
199 static const char __kstrtab_##sym[] \
200 __attribute__((section("__ksymtab_strings"), aligned(1))) \
201 = MODULE_SYMBOL_PREFIX #sym; \
202 static const struct kernel_symbol __ksymtab_##sym \
203 __used \
204 __attribute__((section("__ksymtab" sec), unused)) \
205 = { (unsigned long)&sym, __kstrtab_##sym }
207 #define EXPORT_SYMBOL(sym) \
208 __EXPORT_SYMBOL(sym, "")
210 #define EXPORT_SYMBOL_GPL(sym) \
211 __EXPORT_SYMBOL(sym, "_gpl")
213 #define EXPORT_SYMBOL_GPL_FUTURE(sym) \
214 __EXPORT_SYMBOL(sym, "_gpl_future")
217 #ifdef CONFIG_UNUSED_SYMBOLS
218 #define EXPORT_UNUSED_SYMBOL(sym) __EXPORT_SYMBOL(sym, "_unused")
219 #define EXPORT_UNUSED_SYMBOL_GPL(sym) __EXPORT_SYMBOL(sym, "_unused_gpl")
220 #else
221 #define EXPORT_UNUSED_SYMBOL(sym)
222 #define EXPORT_UNUSED_SYMBOL_GPL(sym)
223 #endif
225 #endif
227 enum module_state
229 MODULE_STATE_LIVE,
230 MODULE_STATE_COMING,
231 MODULE_STATE_GOING,
234 struct module
236 enum module_state state;
238 /* Member of list of modules */
239 struct list_head list;
241 /* Unique handle for this module */
242 char name[MODULE_NAME_LEN];
244 /* Sysfs stuff. */
245 struct module_kobject mkobj;
246 struct module_attribute *modinfo_attrs;
247 const char *version;
248 const char *srcversion;
249 struct kobject *holders_dir;
251 /* Exported symbols */
252 const struct kernel_symbol *syms;
253 const unsigned long *crcs;
254 unsigned int num_syms;
256 /* Kernel parameters. */
257 struct kernel_param *kp;
258 unsigned int num_kp;
260 /* GPL-only exported symbols. */
261 unsigned int num_gpl_syms;
262 const struct kernel_symbol *gpl_syms;
263 const unsigned long *gpl_crcs;
265 #ifdef CONFIG_UNUSED_SYMBOLS
266 /* unused exported symbols. */
267 const struct kernel_symbol *unused_syms;
268 const unsigned long *unused_crcs;
269 unsigned int num_unused_syms;
271 /* GPL-only, unused exported symbols. */
272 unsigned int num_unused_gpl_syms;
273 const struct kernel_symbol *unused_gpl_syms;
274 const unsigned long *unused_gpl_crcs;
275 #endif
277 /* symbols that will be GPL-only in the near future. */
278 const struct kernel_symbol *gpl_future_syms;
279 const unsigned long *gpl_future_crcs;
280 unsigned int num_gpl_future_syms;
282 /* Exception table */
283 unsigned int num_exentries;
284 struct exception_table_entry *extable;
286 /* Startup function. */
287 int (*init)(void);
289 /* If this is non-NULL, vfree after init() returns */
290 void *module_init;
292 /* Here is the actual code + data, vfree'd on unload. */
293 void *module_core;
295 /* Here are the sizes of the init and core sections */
296 unsigned int init_size, core_size;
298 /* The size of the executable code in each section. */
299 unsigned int init_text_size, core_text_size;
301 /* Arch-specific module values */
302 struct mod_arch_specific arch;
304 unsigned int taints; /* same bits as kernel:tainted */
306 #ifdef CONFIG_GENERIC_BUG
307 /* Support for BUG */
308 unsigned num_bugs;
309 struct list_head bug_list;
310 struct bug_entry *bug_table;
311 #endif
313 #ifdef CONFIG_KALLSYMS
315 * We keep the symbol and string tables for kallsyms.
316 * The core_* fields below are temporary, loader-only (they
317 * could really be discarded after module init).
319 Elf_Sym *symtab, *core_symtab;
320 unsigned int num_symtab, core_num_syms;
321 char *strtab, *core_strtab;
323 /* Section attributes */
324 struct module_sect_attrs *sect_attrs;
326 /* Notes attributes */
327 struct module_notes_attrs *notes_attrs;
328 #endif
330 /* Per-cpu data. */
331 void *percpu;
333 /* The command line arguments (may be mangled). People like
334 keeping pointers to this stuff */
335 char *args;
336 #ifdef CONFIG_TRACEPOINTS
337 struct tracepoint *tracepoints;
338 unsigned int num_tracepoints;
339 #endif
341 #ifdef CONFIG_TRACING
342 const char **trace_bprintk_fmt_start;
343 unsigned int num_trace_bprintk_fmt;
344 #endif
345 #ifdef CONFIG_EVENT_TRACING
346 struct ftrace_event_call *trace_events;
347 unsigned int num_trace_events;
348 #endif
349 #ifdef CONFIG_FTRACE_MCOUNT_RECORD
350 unsigned long *ftrace_callsites;
351 unsigned int num_ftrace_callsites;
352 #endif
354 #ifdef CONFIG_MODULE_UNLOAD
355 /* What modules depend on me? */
356 struct list_head modules_which_use_me;
358 /* Who is waiting for us to be unloaded */
359 struct task_struct *waiter;
361 /* Destruction function. */
362 void (*exit)(void);
364 #ifdef CONFIG_SMP
365 char *refptr;
366 #else
367 local_t ref;
368 #endif
369 #endif
371 #ifdef CONFIG_CONSTRUCTORS
372 /* Constructor functions. */
373 ctor_fn_t *ctors;
374 unsigned int num_ctors;
375 #endif
377 #ifndef MODULE_ARCH_INIT
378 #define MODULE_ARCH_INIT {}
379 #endif
381 extern struct mutex module_mutex;
383 /* FIXME: It'd be nice to isolate modules during init, too, so they
384 aren't used before they (may) fail. But presently too much code
385 (IDE & SCSI) require entry into the module during init.*/
386 static inline int module_is_live(struct module *mod)
388 return mod->state != MODULE_STATE_GOING;
391 struct module *__module_text_address(unsigned long addr);
392 struct module *__module_address(unsigned long addr);
393 bool is_module_address(unsigned long addr);
394 bool is_module_text_address(unsigned long addr);
396 static inline int within_module_core(unsigned long addr, struct module *mod)
398 return (unsigned long)mod->module_core <= addr &&
399 addr < (unsigned long)mod->module_core + mod->core_size;
402 static inline int within_module_init(unsigned long addr, struct module *mod)
404 return (unsigned long)mod->module_init <= addr &&
405 addr < (unsigned long)mod->module_init + mod->init_size;
408 /* Search for module by name: must hold module_mutex. */
409 struct module *find_module(const char *name);
411 struct symsearch {
412 const struct kernel_symbol *start, *stop;
413 const unsigned long *crcs;
414 enum {
415 NOT_GPL_ONLY,
416 GPL_ONLY,
417 WILL_BE_GPL_ONLY,
418 } licence;
419 bool unused;
422 /* Search for an exported symbol by name. */
423 const struct kernel_symbol *find_symbol(const char *name,
424 struct module **owner,
425 const unsigned long **crc,
426 bool gplok,
427 bool warn);
429 /* Walk the exported symbol table */
430 bool each_symbol(bool (*fn)(const struct symsearch *arr, struct module *owner,
431 unsigned int symnum, void *data), void *data);
433 /* Returns 0 and fills in value, defined and namebuf, or -ERANGE if
434 symnum out of range. */
435 int module_get_kallsym(unsigned int symnum, unsigned long *value, char *type,
436 char *name, char *module_name, int *exported);
438 /* Look for this name: can be of form module:name. */
439 unsigned long module_kallsyms_lookup_name(const char *name);
441 int module_kallsyms_on_each_symbol(int (*fn)(void *, const char *,
442 struct module *, unsigned long),
443 void *data);
445 extern void __module_put_and_exit(struct module *mod, long code)
446 __attribute__((noreturn));
447 #define module_put_and_exit(code) __module_put_and_exit(THIS_MODULE, code);
449 #ifdef CONFIG_MODULE_UNLOAD
450 unsigned int module_refcount(struct module *mod);
451 void __symbol_put(const char *symbol);
452 #define symbol_put(x) __symbol_put(MODULE_SYMBOL_PREFIX #x)
453 void symbol_put_addr(void *addr);
455 static inline local_t *__module_ref_addr(struct module *mod, int cpu)
457 #ifdef CONFIG_SMP
458 return (local_t *) (mod->refptr + per_cpu_offset(cpu));
459 #else
460 return &mod->ref;
461 #endif
464 /* Sometimes we know we already have a refcount, and it's easier not
465 to handle the error case (which only happens with rmmod --wait). */
466 static inline void __module_get(struct module *module)
468 if (module) {
469 unsigned int cpu = get_cpu();
470 local_inc(__module_ref_addr(module, cpu));
471 trace_module_get(module, _THIS_IP_,
472 local_read(__module_ref_addr(module, cpu)));
473 put_cpu();
477 static inline int try_module_get(struct module *module)
479 int ret = 1;
481 if (module) {
482 unsigned int cpu = get_cpu();
483 if (likely(module_is_live(module))) {
484 local_inc(__module_ref_addr(module, cpu));
485 trace_module_get(module, _THIS_IP_,
486 local_read(__module_ref_addr(module, cpu)));
488 else
489 ret = 0;
490 put_cpu();
492 return ret;
495 extern void module_put(struct module *module);
497 #else /*!CONFIG_MODULE_UNLOAD*/
498 static inline int try_module_get(struct module *module)
500 return !module || module_is_live(module);
502 static inline void module_put(struct module *module)
505 static inline void __module_get(struct module *module)
508 #define symbol_put(x) do { } while(0)
509 #define symbol_put_addr(p) do { } while(0)
511 #endif /* CONFIG_MODULE_UNLOAD */
512 int use_module(struct module *a, struct module *b);
514 /* This is a #define so the string doesn't get put in every .o file */
515 #define module_name(mod) \
516 ({ \
517 struct module *__mod = (mod); \
518 __mod ? __mod->name : "kernel"; \
521 /* For kallsyms to ask for address resolution. namebuf should be at
522 * least KSYM_NAME_LEN long: a pointer to namebuf is returned if
523 * found, otherwise NULL. */
524 const char *module_address_lookup(unsigned long addr,
525 unsigned long *symbolsize,
526 unsigned long *offset,
527 char **modname,
528 char *namebuf);
529 int lookup_module_symbol_name(unsigned long addr, char *symname);
530 int lookup_module_symbol_attrs(unsigned long addr, unsigned long *size, unsigned long *offset, char *modname, char *name);
532 /* For extable.c to search modules' exception tables. */
533 const struct exception_table_entry *search_module_extables(unsigned long addr);
535 int register_module_notifier(struct notifier_block * nb);
536 int unregister_module_notifier(struct notifier_block * nb);
538 extern void print_modules(void);
540 extern void module_update_tracepoints(void);
541 extern int module_get_iter_tracepoints(struct tracepoint_iter *iter);
543 #else /* !CONFIG_MODULES... */
544 #define EXPORT_SYMBOL(sym)
545 #define EXPORT_SYMBOL_GPL(sym)
546 #define EXPORT_SYMBOL_GPL_FUTURE(sym)
547 #define EXPORT_UNUSED_SYMBOL(sym)
548 #define EXPORT_UNUSED_SYMBOL_GPL(sym)
550 /* Given an address, look for it in the exception tables. */
551 static inline const struct exception_table_entry *
552 search_module_extables(unsigned long addr)
554 return NULL;
557 static inline struct module *__module_address(unsigned long addr)
559 return NULL;
562 static inline struct module *__module_text_address(unsigned long addr)
564 return NULL;
567 static inline bool is_module_address(unsigned long addr)
569 return false;
572 static inline bool is_module_text_address(unsigned long addr)
574 return false;
577 /* Get/put a kernel symbol (calls should be symmetric) */
578 #define symbol_get(x) ({ extern typeof(x) x __attribute__((weak)); &(x); })
579 #define symbol_put(x) do { } while(0)
580 #define symbol_put_addr(x) do { } while(0)
582 static inline void __module_get(struct module *module)
586 static inline int try_module_get(struct module *module)
588 return 1;
591 static inline void module_put(struct module *module)
595 #define module_name(mod) "kernel"
597 /* For kallsyms to ask for address resolution. NULL means not found. */
598 static inline const char *module_address_lookup(unsigned long addr,
599 unsigned long *symbolsize,
600 unsigned long *offset,
601 char **modname,
602 char *namebuf)
604 return NULL;
607 static inline int lookup_module_symbol_name(unsigned long addr, char *symname)
609 return -ERANGE;
612 static inline int lookup_module_symbol_attrs(unsigned long addr, unsigned long *size, unsigned long *offset, char *modname, char *name)
614 return -ERANGE;
617 static inline int module_get_kallsym(unsigned int symnum, unsigned long *value,
618 char *type, char *name,
619 char *module_name, int *exported)
621 return -ERANGE;
624 static inline unsigned long module_kallsyms_lookup_name(const char *name)
626 return 0;
629 static inline int module_kallsyms_on_each_symbol(int (*fn)(void *, const char *,
630 struct module *,
631 unsigned long),
632 void *data)
634 return 0;
637 static inline int register_module_notifier(struct notifier_block * nb)
639 /* no events will happen anyway, so this can always succeed */
640 return 0;
643 static inline int unregister_module_notifier(struct notifier_block * nb)
645 return 0;
648 #define module_put_and_exit(code) do_exit(code)
650 static inline void print_modules(void)
654 static inline void module_update_tracepoints(void)
658 static inline int module_get_iter_tracepoints(struct tracepoint_iter *iter)
660 return 0;
663 #endif /* CONFIG_MODULES */
665 struct device_driver;
666 #ifdef CONFIG_SYSFS
667 struct module;
669 extern struct kset *module_kset;
670 extern struct kobj_type module_ktype;
671 extern int module_sysfs_initialized;
673 int mod_sysfs_init(struct module *mod);
674 int mod_sysfs_setup(struct module *mod,
675 struct kernel_param *kparam,
676 unsigned int num_params);
677 int module_add_modinfo_attrs(struct module *mod);
678 void module_remove_modinfo_attrs(struct module *mod);
680 #else /* !CONFIG_SYSFS */
682 static inline int mod_sysfs_init(struct module *mod)
684 return 0;
687 static inline int mod_sysfs_setup(struct module *mod,
688 struct kernel_param *kparam,
689 unsigned int num_params)
691 return 0;
694 static inline int module_add_modinfo_attrs(struct module *mod)
696 return 0;
699 static inline void module_remove_modinfo_attrs(struct module *mod)
702 #endif /* CONFIG_SYSFS */
704 #define symbol_request(x) try_then_request_module(symbol_get(x), "symbol:" #x)
706 /* BELOW HERE ALL THESE ARE OBSOLETE AND WILL VANISH */
708 #define __MODULE_STRING(x) __stringify(x)
711 #ifdef CONFIG_GENERIC_BUG
712 int module_bug_finalize(const Elf_Ehdr *, const Elf_Shdr *,
713 struct module *);
714 void module_bug_cleanup(struct module *);
716 #else /* !CONFIG_GENERIC_BUG */
718 static inline int module_bug_finalize(const Elf_Ehdr *hdr,
719 const Elf_Shdr *sechdrs,
720 struct module *mod)
722 return 0;
724 static inline void module_bug_cleanup(struct module *mod) {}
725 #endif /* CONFIG_GENERIC_BUG */
727 #endif /* _LINUX_MODULE_H */