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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/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>
19
20 #include <linux/percpu.h>
21 #include <asm/module.h>
22
23 #include <trace/events/module.h>
24
25 /* Not Yet Implemented */
26 #define MODULE_SUPPORTED_DEVICE(name)
27
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
34
35 #define MODULE_NAME_LEN MAX_PARAM_PREFIX_LEN
36
37 struct kernel_symbol
38 {
39 unsigned long value;
40 const char *name;
41 };
42
43 struct modversion_info
44 {
45 unsigned long crc;
46 char name[MODULE_NAME_LEN];
47 };
48
49 struct module;
50
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 *);
59 };
60
61 struct module_kobject
62 {
63 struct kobject kobj;
64 struct module *mod;
65 struct kobject *drivers_dir;
66 struct module_param_attrs *mp;
67 };
68
69 /* These are either module local, or the kernel's dummy ones. */
70 extern int init_module(void);
71 extern void cleanup_module(void);
72
73 /* Archs provide a method of finding the correct exception table. */
74 struct exception_table_entry;
75
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);
84
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))))
89
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
96
97 /* Generic info of form tag = "info" */
98 #define MODULE_INFO(tag, info) __MODULE_INFO(tag, tag, info)
99
100 /* For userspace: you can also call me... */
101 #define MODULE_ALIAS(_alias) MODULE_INFO(alias, _alias)
102
103 /*
104 * The following license idents are currently accepted as indicating free
105 * software modules
106 *
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]
116 *
117 * The following other idents are available
118 *
119 * "Proprietary" [Non free products]
120 *
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.
124 *
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
130 */
131 #define MODULE_LICENSE(_license) MODULE_INFO(license, _license)
132
133 /*
134 * Author(s), use "Name <email>" or just "Name", for multiple
135 * authors use multiple MODULE_AUTHOR() statements/lines.
136 */
137 #define MODULE_AUTHOR(_author) MODULE_INFO(author, _author)
138
139 /* What your module does. */
140 #define MODULE_DESCRIPTION(_description) MODULE_INFO(description, _description)
141
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)
146
147 #define MODULE_DEVICE_TABLE(type,name) \
148 MODULE_GENERIC_TABLE(type##_device,name)
149
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".
160
161 Using this automatically adds a checksum of the .c files and the
162 local headers in "srcversion".
163 */
164 #define MODULE_VERSION(_version) MODULE_INFO(version, _version)
165
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)
170
171 /* Given an address, look for it in the exception tables */
172 const struct exception_table_entry *search_exception_tables(unsigned long add);
173
174 struct notifier_block;
175
176 #ifdef CONFIG_MODULES
177
178 /* Get/put a kernel symbol (calls must be symmetric) */
179 void *__symbol_get(const char *symbol);
180 void *__symbol_get_gpl(const char *symbol);
181 #define symbol_get(x) ((typeof(&x))(__symbol_get(MODULE_SYMBOL_PREFIX #x)))
182
183 #ifndef __GENKSYMS__
184 #ifdef CONFIG_MODVERSIONS
185 /* Mark the CRC weak since genksyms apparently decides not to
186 * generate a checksums for some symbols */
187 #define __CRC_SYMBOL(sym, sec) \
188 extern void *__crc_##sym __attribute__((weak)); \
189 static const unsigned long __kcrctab_##sym \
190 __used \
191 __attribute__((section("__kcrctab" sec), unused)) \
192 = (unsigned long) &__crc_##sym;
193 #else
194 #define __CRC_SYMBOL(sym, sec)
195 #endif
196
197 /* For every exported symbol, place a struct in the __ksymtab section */
198 #define __EXPORT_SYMBOL(sym, sec) \
199 extern typeof(sym) sym; \
200 __CRC_SYMBOL(sym, sec) \
201 static const char __kstrtab_##sym[] \
202 __attribute__((section("__ksymtab_strings"), aligned(1))) \
203 = MODULE_SYMBOL_PREFIX #sym; \
204 static const struct kernel_symbol __ksymtab_##sym \
205 __used \
206 __attribute__((section("__ksymtab" sec), unused)) \
207 = { (unsigned long)&sym, __kstrtab_##sym }
208
209 #define EXPORT_SYMBOL(sym) \
210 __EXPORT_SYMBOL(sym, "")
211
212 #define EXPORT_SYMBOL_GPL(sym) \
213 __EXPORT_SYMBOL(sym, "_gpl")
214
215 #define EXPORT_SYMBOL_GPL_FUTURE(sym) \
216 __EXPORT_SYMBOL(sym, "_gpl_future")
217
218
219 #ifdef CONFIG_UNUSED_SYMBOLS
220 #define EXPORT_UNUSED_SYMBOL(sym) __EXPORT_SYMBOL(sym, "_unused")
221 #define EXPORT_UNUSED_SYMBOL_GPL(sym) __EXPORT_SYMBOL(sym, "_unused_gpl")
222 #else
223 #define EXPORT_UNUSED_SYMBOL(sym)
224 #define EXPORT_UNUSED_SYMBOL_GPL(sym)
225 #endif
226
227 #endif
228
229 enum module_state
230 {
231 MODULE_STATE_LIVE,
232 MODULE_STATE_COMING,
233 MODULE_STATE_GOING,
234 };
235
236 struct module
237 {
238 enum module_state state;
239
240 /* Member of list of modules */
241 struct list_head list;
242
243 /* Unique handle for this module */
244 char name[MODULE_NAME_LEN];
245
246 /* Sysfs stuff. */
247 struct module_kobject mkobj;
248 struct module_attribute *modinfo_attrs;
249 const char *version;
250 const char *srcversion;
251 struct kobject *holders_dir;
252
253 /* Exported symbols */
254 const struct kernel_symbol *syms;
255 const unsigned long *crcs;
256 unsigned int num_syms;
257
258 /* Kernel parameters. */
259 struct kernel_param *kp;
260 unsigned int num_kp;
261
262 /* GPL-only exported symbols. */
263 unsigned int num_gpl_syms;
264 const struct kernel_symbol *gpl_syms;
265 const unsigned long *gpl_crcs;
266
267 #ifdef CONFIG_UNUSED_SYMBOLS
268 /* unused exported symbols. */
269 const struct kernel_symbol *unused_syms;
270 const unsigned long *unused_crcs;
271 unsigned int num_unused_syms;
272
273 /* GPL-only, unused exported symbols. */
274 unsigned int num_unused_gpl_syms;
275 const struct kernel_symbol *unused_gpl_syms;
276 const unsigned long *unused_gpl_crcs;
277 #endif
278
279 /* symbols that will be GPL-only in the near future. */
280 const struct kernel_symbol *gpl_future_syms;
281 const unsigned long *gpl_future_crcs;
282 unsigned int num_gpl_future_syms;
283
284 /* Exception table */
285 unsigned int num_exentries;
286 struct exception_table_entry *extable;
287
288 /* Startup function. */
289 int (*init)(void);
290
291 /* If this is non-NULL, vfree after init() returns */
292 void *module_init;
293
294 /* Here is the actual code + data, vfree'd on unload. */
295 void *module_core;
296
297 /* Here are the sizes of the init and core sections */
298 unsigned int init_size, core_size;
299
300 /* The size of the executable code in each section. */
301 unsigned int init_text_size, core_text_size;
302
303 /* Arch-specific module values */
304 struct mod_arch_specific arch;
305
306 unsigned int taints; /* same bits as kernel:tainted */
307
308 #ifdef CONFIG_GENERIC_BUG
309 /* Support for BUG */
310 unsigned num_bugs;
311 struct list_head bug_list;
312 struct bug_entry *bug_table;
313 #endif
314
315 #ifdef CONFIG_KALLSYMS
316 /*
317 * We keep the symbol and string tables for kallsyms.
318 * The core_* fields below are temporary, loader-only (they
319 * could really be discarded after module init).
320 */
321 Elf_Sym *symtab, *core_symtab;
322 unsigned int num_symtab, core_num_syms;
323 char *strtab, *core_strtab;
324
325 /* Section attributes */
326 struct module_sect_attrs *sect_attrs;
327
328 /* Notes attributes */
329 struct module_notes_attrs *notes_attrs;
330 #endif
331
332 /* Per-cpu data. */
333 void *percpu;
334
335 /* The command line arguments (may be mangled). People like
336 keeping pointers to this stuff */
337 char *args;
338 #ifdef CONFIG_TRACEPOINTS
339 struct tracepoint *tracepoints;
340 unsigned int num_tracepoints;
341 #endif
342
343 #ifdef CONFIG_TRACING
344 const char **trace_bprintk_fmt_start;
345 unsigned int num_trace_bprintk_fmt;
346 #endif
347 #ifdef CONFIG_EVENT_TRACING
348 struct ftrace_event_call *trace_events;
349 unsigned int num_trace_events;
350 #endif
351 #ifdef CONFIG_FTRACE_MCOUNT_RECORD
352 unsigned long *ftrace_callsites;
353 unsigned int num_ftrace_callsites;
354 #endif
355
356 #ifdef CONFIG_MODULE_UNLOAD
357 /* What modules depend on me? */
358 struct list_head modules_which_use_me;
359
360 /* Who is waiting for us to be unloaded */
361 struct task_struct *waiter;
362
363 /* Destruction function. */
364 void (*exit)(void);
365
366 struct module_ref {
367 int count;
368 } __percpu *refptr;
369 #endif
370
371 #ifdef CONFIG_CONSTRUCTORS
372 /* Constructor functions. */
373 ctor_fn_t *ctors;
374 unsigned int num_ctors;
375 #endif
376 };
377 #ifndef MODULE_ARCH_INIT
378 #define MODULE_ARCH_INIT {}
379 #endif
380
381 extern struct mutex module_mutex;
382
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)
387 {
388 return mod->state != MODULE_STATE_GOING;
389 }
390
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);
395
396 static inline int within_module_core(unsigned long addr, struct module *mod)
397 {
398 return (unsigned long)mod->module_core <= addr &&
399 addr < (unsigned long)mod->module_core + mod->core_size;
400 }
401
402 static inline int within_module_init(unsigned long addr, struct module *mod)
403 {
404 return (unsigned long)mod->module_init <= addr &&
405 addr < (unsigned long)mod->module_init + mod->init_size;
406 }
407
408 /* Search for module by name: must hold module_mutex. */
409 struct module *find_module(const char *name);
410
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;
420 };
421
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);
428
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);
432
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);
437
438 /* Look for this name: can be of form module:name. */
439 unsigned long module_kallsyms_lookup_name(const char *name);
440
441 int module_kallsyms_on_each_symbol(int (*fn)(void *, const char *,
442 struct module *, unsigned long),
443 void *data);
444
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);
448
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);
454
455 /* Sometimes we know we already have a refcount, and it's easier not
456 to handle the error case (which only happens with rmmod --wait). */
457 static inline void __module_get(struct module *module)
458 {
459 if (module) {
460 preempt_disable();
461 __this_cpu_inc(module->refptr->count);
462 trace_module_get(module, _THIS_IP_,
463 __this_cpu_read(module->refptr->count));
464 preempt_enable();
465 }
466 }
467
468 static inline int try_module_get(struct module *module)
469 {
470 int ret = 1;
471
472 if (module) {
473 preempt_disable();
474
475 if (likely(module_is_live(module))) {
476 __this_cpu_inc(module->refptr->count);
477 trace_module_get(module, _THIS_IP_,
478 __this_cpu_read(module->refptr->count));
479 }
480 else
481 ret = 0;
482
483 preempt_enable();
484 }
485 return ret;
486 }
487
488 extern void module_put(struct module *module);
489
490 #else /*!CONFIG_MODULE_UNLOAD*/
491 static inline int try_module_get(struct module *module)
492 {
493 return !module || module_is_live(module);
494 }
495 static inline void module_put(struct module *module)
496 {
497 }
498 static inline void __module_get(struct module *module)
499 {
500 }
501 #define symbol_put(x) do { } while(0)
502 #define symbol_put_addr(p) do { } while(0)
503
504 #endif /* CONFIG_MODULE_UNLOAD */
505 int use_module(struct module *a, struct module *b);
506
507 /* This is a #define so the string doesn't get put in every .o file */
508 #define module_name(mod) \
509 ({ \
510 struct module *__mod = (mod); \
511 __mod ? __mod->name : "kernel"; \
512 })
513
514 /* For kallsyms to ask for address resolution. namebuf should be at
515 * least KSYM_NAME_LEN long: a pointer to namebuf is returned if
516 * found, otherwise NULL. */
517 const char *module_address_lookup(unsigned long addr,
518 unsigned long *symbolsize,
519 unsigned long *offset,
520 char **modname,
521 char *namebuf);
522 int lookup_module_symbol_name(unsigned long addr, char *symname);
523 int lookup_module_symbol_attrs(unsigned long addr, unsigned long *size, unsigned long *offset, char *modname, char *name);
524
525 /* For extable.c to search modules' exception tables. */
526 const struct exception_table_entry *search_module_extables(unsigned long addr);
527
528 int register_module_notifier(struct notifier_block * nb);
529 int unregister_module_notifier(struct notifier_block * nb);
530
531 extern void print_modules(void);
532
533 extern void module_update_tracepoints(void);
534 extern int module_get_iter_tracepoints(struct tracepoint_iter *iter);
535
536 #else /* !CONFIG_MODULES... */
537 #define EXPORT_SYMBOL(sym)
538 #define EXPORT_SYMBOL_GPL(sym)
539 #define EXPORT_SYMBOL_GPL_FUTURE(sym)
540 #define EXPORT_UNUSED_SYMBOL(sym)
541 #define EXPORT_UNUSED_SYMBOL_GPL(sym)
542
543 /* Given an address, look for it in the exception tables. */
544 static inline const struct exception_table_entry *
545 search_module_extables(unsigned long addr)
546 {
547 return NULL;
548 }
549
550 static inline struct module *__module_address(unsigned long addr)
551 {
552 return NULL;
553 }
554
555 static inline struct module *__module_text_address(unsigned long addr)
556 {
557 return NULL;
558 }
559
560 static inline bool is_module_address(unsigned long addr)
561 {
562 return false;
563 }
564
565 static inline bool is_module_text_address(unsigned long addr)
566 {
567 return false;
568 }
569
570 /* Get/put a kernel symbol (calls should be symmetric) */
571 #define symbol_get(x) ({ extern typeof(x) x __attribute__((weak)); &(x); })
572 #define symbol_put(x) do { } while(0)
573 #define symbol_put_addr(x) do { } while(0)
574
575 static inline void __module_get(struct module *module)
576 {
577 }
578
579 static inline int try_module_get(struct module *module)
580 {
581 return 1;
582 }
583
584 static inline void module_put(struct module *module)
585 {
586 }
587
588 #define module_name(mod) "kernel"
589
590 /* For kallsyms to ask for address resolution. NULL means not found. */
591 static inline const char *module_address_lookup(unsigned long addr,
592 unsigned long *symbolsize,
593 unsigned long *offset,
594 char **modname,
595 char *namebuf)
596 {
597 return NULL;
598 }
599
600 static inline int lookup_module_symbol_name(unsigned long addr, char *symname)
601 {
602 return -ERANGE;
603 }
604
605 static inline int lookup_module_symbol_attrs(unsigned long addr, unsigned long *size, unsigned long *offset, char *modname, char *name)
606 {
607 return -ERANGE;
608 }
609
610 static inline int module_get_kallsym(unsigned int symnum, unsigned long *value,
611 char *type, char *name,
612 char *module_name, int *exported)
613 {
614 return -ERANGE;
615 }
616
617 static inline unsigned long module_kallsyms_lookup_name(const char *name)
618 {
619 return 0;
620 }
621
622 static inline int module_kallsyms_on_each_symbol(int (*fn)(void *, const char *,
623 struct module *,
624 unsigned long),
625 void *data)
626 {
627 return 0;
628 }
629
630 static inline int register_module_notifier(struct notifier_block * nb)
631 {
632 /* no events will happen anyway, so this can always succeed */
633 return 0;
634 }
635
636 static inline int unregister_module_notifier(struct notifier_block * nb)
637 {
638 return 0;
639 }
640
641 #define module_put_and_exit(code) do_exit(code)
642
643 static inline void print_modules(void)
644 {
645 }
646
647 static inline void module_update_tracepoints(void)
648 {
649 }
650
651 static inline int module_get_iter_tracepoints(struct tracepoint_iter *iter)
652 {
653 return 0;
654 }
655
656 #endif /* CONFIG_MODULES */
657
658 struct device_driver;
659 #ifdef CONFIG_SYSFS
660 struct module;
661
662 extern struct kset *module_kset;
663 extern struct kobj_type module_ktype;
664 extern int module_sysfs_initialized;
665
666 int mod_sysfs_init(struct module *mod);
667 int mod_sysfs_setup(struct module *mod,
668 struct kernel_param *kparam,
669 unsigned int num_params);
670 int module_add_modinfo_attrs(struct module *mod);
671 void module_remove_modinfo_attrs(struct module *mod);
672
673 #else /* !CONFIG_SYSFS */
674
675 static inline int mod_sysfs_init(struct module *mod)
676 {
677 return 0;
678 }
679
680 static inline int mod_sysfs_setup(struct module *mod,
681 struct kernel_param *kparam,
682 unsigned int num_params)
683 {
684 return 0;
685 }
686
687 static inline int module_add_modinfo_attrs(struct module *mod)
688 {
689 return 0;
690 }
691
692 static inline void module_remove_modinfo_attrs(struct module *mod)
693 { }
694
695 #endif /* CONFIG_SYSFS */
696
697 #define symbol_request(x) try_then_request_module(symbol_get(x), "symbol:" #x)
698
699 /* BELOW HERE ALL THESE ARE OBSOLETE AND WILL VANISH */
700
701 #define __MODULE_STRING(x) __stringify(x)
702
703
704 #ifdef CONFIG_GENERIC_BUG
705 int module_bug_finalize(const Elf_Ehdr *, const Elf_Shdr *,
706 struct module *);
707 void module_bug_cleanup(struct module *);
708
709 #else /* !CONFIG_GENERIC_BUG */
710
711 static inline int module_bug_finalize(const Elf_Ehdr *hdr,
712 const Elf_Shdr *sechdrs,
713 struct module *mod)
714 {
715 return 0;
716 }
717 static inline void module_bug_cleanup(struct module *mod) {}
718 #endif /* CONFIG_GENERIC_BUG */
719
720 #endif /* _LINUX_MODULE_H */