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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 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)))
183
184 #ifndef __GENKSYMS__
185 #ifdef CONFIG_MODVERSIONS
186 /* Mark the CRC weak since genksyms apparently decides not to
187 * generate a checksums for some symbols */
188 #define __CRC_SYMBOL(sym, sec) \
189 extern void *__crc_##sym __attribute__((weak)); \
190 static const unsigned long __kcrctab_##sym \
191 __used \
192 __attribute__((section("__kcrctab" sec), unused)) \
193 = (unsigned long) &__crc_##sym;
194 #else
195 #define __CRC_SYMBOL(sym, sec)
196 #endif
197
198 /* For every exported symbol, place a struct in the __ksymtab section */
199 #define __EXPORT_SYMBOL(sym, sec) \
200 extern typeof(sym) sym; \
201 __CRC_SYMBOL(sym, sec) \
202 static const char __kstrtab_##sym[] \
203 __attribute__((section("__ksymtab_strings"), aligned(1))) \
204 = MODULE_SYMBOL_PREFIX #sym; \
205 static const struct kernel_symbol __ksymtab_##sym \
206 __used \
207 __attribute__((section("__ksymtab" sec), unused)) \
208 = { (unsigned long)&sym, __kstrtab_##sym }
209
210 #define EXPORT_SYMBOL(sym) \
211 __EXPORT_SYMBOL(sym, "")
212
213 #define EXPORT_SYMBOL_GPL(sym) \
214 __EXPORT_SYMBOL(sym, "_gpl")
215
216 #define EXPORT_SYMBOL_GPL_FUTURE(sym) \
217 __EXPORT_SYMBOL(sym, "_gpl_future")
218
219
220 #ifdef CONFIG_UNUSED_SYMBOLS
221 #define EXPORT_UNUSED_SYMBOL(sym) __EXPORT_SYMBOL(sym, "_unused")
222 #define EXPORT_UNUSED_SYMBOL_GPL(sym) __EXPORT_SYMBOL(sym, "_unused_gpl")
223 #else
224 #define EXPORT_UNUSED_SYMBOL(sym)
225 #define EXPORT_UNUSED_SYMBOL_GPL(sym)
226 #endif
227
228 #endif
229
230 enum module_state
231 {
232 MODULE_STATE_LIVE,
233 MODULE_STATE_COMING,
234 MODULE_STATE_GOING,
235 };
236
237 struct module
238 {
239 enum module_state state;
240
241 /* Member of list of modules */
242 struct list_head list;
243
244 /* Unique handle for this module */
245 char name[MODULE_NAME_LEN];
246
247 /* Sysfs stuff. */
248 struct module_kobject mkobj;
249 struct module_attribute *modinfo_attrs;
250 const char *version;
251 const char *srcversion;
252 struct kobject *holders_dir;
253
254 /* Exported symbols */
255 const struct kernel_symbol *syms;
256 const unsigned long *crcs;
257 unsigned int num_syms;
258
259 /* Kernel parameters. */
260 struct kernel_param *kp;
261 unsigned int num_kp;
262
263 /* GPL-only exported symbols. */
264 unsigned int num_gpl_syms;
265 const struct kernel_symbol *gpl_syms;
266 const unsigned long *gpl_crcs;
267
268 #ifdef CONFIG_UNUSED_SYMBOLS
269 /* unused exported symbols. */
270 const struct kernel_symbol *unused_syms;
271 const unsigned long *unused_crcs;
272 unsigned int num_unused_syms;
273
274 /* GPL-only, unused exported symbols. */
275 unsigned int num_unused_gpl_syms;
276 const struct kernel_symbol *unused_gpl_syms;
277 const unsigned long *unused_gpl_crcs;
278 #endif
279
280 /* symbols that will be GPL-only in the near future. */
281 const struct kernel_symbol *gpl_future_syms;
282 const unsigned long *gpl_future_crcs;
283 unsigned int num_gpl_future_syms;
284
285 /* Exception table */
286 unsigned int num_exentries;
287 struct exception_table_entry *extable;
288
289 /* Startup function. */
290 int (*init)(void);
291
292 /* If this is non-NULL, vfree after init() returns */
293 void *module_init;
294
295 /* Here is the actual code + data, vfree'd on unload. */
296 void *module_core;
297
298 /* Here are the sizes of the init and core sections */
299 unsigned int init_size, core_size;
300
301 /* The size of the executable code in each section. */
302 unsigned int init_text_size, core_text_size;
303
304 /* Arch-specific module values */
305 struct mod_arch_specific arch;
306
307 unsigned int taints; /* same bits as kernel:tainted */
308
309 #ifdef CONFIG_GENERIC_BUG
310 /* Support for BUG */
311 unsigned num_bugs;
312 struct list_head bug_list;
313 struct bug_entry *bug_table;
314 #endif
315
316 #ifdef CONFIG_KALLSYMS
317 /*
318 * We keep the symbol and string tables for kallsyms.
319 * The core_* fields below are temporary, loader-only (they
320 * could really be discarded after module init).
321 */
322 Elf_Sym *symtab, *core_symtab;
323 unsigned int num_symtab, core_num_syms;
324 char *strtab, *core_strtab;
325
326 /* Section attributes */
327 struct module_sect_attrs *sect_attrs;
328
329 /* Notes attributes */
330 struct module_notes_attrs *notes_attrs;
331 #endif
332
333 #ifdef CONFIG_SMP
334 /* Per-cpu data. */
335 void __percpu *percpu;
336 unsigned int percpu_size;
337 #endif
338
339 /* The command line arguments (may be mangled). People like
340 keeping pointers to this stuff */
341 char *args;
342 #ifdef CONFIG_TRACEPOINTS
343 struct tracepoint *tracepoints;
344 unsigned int num_tracepoints;
345 #endif
346
347 #ifdef CONFIG_TRACING
348 const char **trace_bprintk_fmt_start;
349 unsigned int num_trace_bprintk_fmt;
350 #endif
351 #ifdef CONFIG_EVENT_TRACING
352 struct ftrace_event_call *trace_events;
353 unsigned int num_trace_events;
354 #endif
355 #ifdef CONFIG_FTRACE_MCOUNT_RECORD
356 unsigned long *ftrace_callsites;
357 unsigned int num_ftrace_callsites;
358 #endif
359
360 #ifdef CONFIG_MODULE_UNLOAD
361 /* What modules depend on me? */
362 struct list_head modules_which_use_me;
363
364 /* Who is waiting for us to be unloaded */
365 struct task_struct *waiter;
366
367 /* Destruction function. */
368 void (*exit)(void);
369
370 struct module_ref {
371 int count;
372 } __percpu *refptr;
373 #endif
374
375 #ifdef CONFIG_CONSTRUCTORS
376 /* Constructor functions. */
377 ctor_fn_t *ctors;
378 unsigned int num_ctors;
379 #endif
380 };
381 #ifndef MODULE_ARCH_INIT
382 #define MODULE_ARCH_INIT {}
383 #endif
384
385 extern struct mutex module_mutex;
386
387 /* FIXME: It'd be nice to isolate modules during init, too, so they
388 aren't used before they (may) fail. But presently too much code
389 (IDE & SCSI) require entry into the module during init.*/
390 static inline int module_is_live(struct module *mod)
391 {
392 return mod->state != MODULE_STATE_GOING;
393 }
394
395 struct module *__module_text_address(unsigned long addr);
396 struct module *__module_address(unsigned long addr);
397 bool is_module_address(unsigned long addr);
398 bool is_module_percpu_address(unsigned long addr);
399 bool is_module_text_address(unsigned long addr);
400
401 static inline int within_module_core(unsigned long addr, struct module *mod)
402 {
403 return (unsigned long)mod->module_core <= addr &&
404 addr < (unsigned long)mod->module_core + mod->core_size;
405 }
406
407 static inline int within_module_init(unsigned long addr, struct module *mod)
408 {
409 return (unsigned long)mod->module_init <= addr &&
410 addr < (unsigned long)mod->module_init + mod->init_size;
411 }
412
413 /* Search for module by name: must hold module_mutex. */
414 struct module *find_module(const char *name);
415
416 struct symsearch {
417 const struct kernel_symbol *start, *stop;
418 const unsigned long *crcs;
419 enum {
420 NOT_GPL_ONLY,
421 GPL_ONLY,
422 WILL_BE_GPL_ONLY,
423 } licence;
424 bool unused;
425 };
426
427 /* Search for an exported symbol by name. */
428 const struct kernel_symbol *find_symbol(const char *name,
429 struct module **owner,
430 const unsigned long **crc,
431 bool gplok,
432 bool warn);
433
434 /* Walk the exported symbol table */
435 bool each_symbol(bool (*fn)(const struct symsearch *arr, struct module *owner,
436 unsigned int symnum, void *data), void *data);
437
438 /* Returns 0 and fills in value, defined and namebuf, or -ERANGE if
439 symnum out of range. */
440 int module_get_kallsym(unsigned int symnum, unsigned long *value, char *type,
441 char *name, char *module_name, int *exported);
442
443 /* Look for this name: can be of form module:name. */
444 unsigned long module_kallsyms_lookup_name(const char *name);
445
446 int module_kallsyms_on_each_symbol(int (*fn)(void *, const char *,
447 struct module *, unsigned long),
448 void *data);
449
450 extern void __module_put_and_exit(struct module *mod, long code)
451 __attribute__((noreturn));
452 #define module_put_and_exit(code) __module_put_and_exit(THIS_MODULE, code);
453
454 #ifdef CONFIG_MODULE_UNLOAD
455 unsigned int module_refcount(struct module *mod);
456 void __symbol_put(const char *symbol);
457 #define symbol_put(x) __symbol_put(MODULE_SYMBOL_PREFIX #x)
458 void symbol_put_addr(void *addr);
459
460 /* Sometimes we know we already have a refcount, and it's easier not
461 to handle the error case (which only happens with rmmod --wait). */
462 static inline void __module_get(struct module *module)
463 {
464 if (module) {
465 preempt_disable();
466 __this_cpu_inc(module->refptr->count);
467 trace_module_get(module, _THIS_IP_,
468 __this_cpu_read(module->refptr->count));
469 preempt_enable();
470 }
471 }
472
473 static inline int try_module_get(struct module *module)
474 {
475 int ret = 1;
476
477 if (module) {
478 preempt_disable();
479
480 if (likely(module_is_live(module))) {
481 __this_cpu_inc(module->refptr->count);
482 trace_module_get(module, _THIS_IP_,
483 __this_cpu_read(module->refptr->count));
484 }
485 else
486 ret = 0;
487
488 preempt_enable();
489 }
490 return ret;
491 }
492
493 extern void module_put(struct module *module);
494
495 #else /*!CONFIG_MODULE_UNLOAD*/
496 static inline int try_module_get(struct module *module)
497 {
498 return !module || module_is_live(module);
499 }
500 static inline void module_put(struct module *module)
501 {
502 }
503 static inline void __module_get(struct module *module)
504 {
505 }
506 #define symbol_put(x) do { } while(0)
507 #define symbol_put_addr(p) do { } while(0)
508
509 #endif /* CONFIG_MODULE_UNLOAD */
510 int use_module(struct module *a, struct module *b);
511
512 /* This is a #define so the string doesn't get put in every .o file */
513 #define module_name(mod) \
514 ({ \
515 struct module *__mod = (mod); \
516 __mod ? __mod->name : "kernel"; \
517 })
518
519 /* For kallsyms to ask for address resolution. namebuf should be at
520 * least KSYM_NAME_LEN long: a pointer to namebuf is returned if
521 * found, otherwise NULL. */
522 const char *module_address_lookup(unsigned long addr,
523 unsigned long *symbolsize,
524 unsigned long *offset,
525 char **modname,
526 char *namebuf);
527 int lookup_module_symbol_name(unsigned long addr, char *symname);
528 int lookup_module_symbol_attrs(unsigned long addr, unsigned long *size, unsigned long *offset, char *modname, char *name);
529
530 /* For extable.c to search modules' exception tables. */
531 const struct exception_table_entry *search_module_extables(unsigned long addr);
532
533 int register_module_notifier(struct notifier_block * nb);
534 int unregister_module_notifier(struct notifier_block * nb);
535
536 extern void print_modules(void);
537
538 extern void module_update_tracepoints(void);
539 extern int module_get_iter_tracepoints(struct tracepoint_iter *iter);
540
541 #else /* !CONFIG_MODULES... */
542 #define EXPORT_SYMBOL(sym)
543 #define EXPORT_SYMBOL_GPL(sym)
544 #define EXPORT_SYMBOL_GPL_FUTURE(sym)
545 #define EXPORT_UNUSED_SYMBOL(sym)
546 #define EXPORT_UNUSED_SYMBOL_GPL(sym)
547
548 /* Given an address, look for it in the exception tables. */
549 static inline const struct exception_table_entry *
550 search_module_extables(unsigned long addr)
551 {
552 return NULL;
553 }
554
555 static inline struct module *__module_address(unsigned long addr)
556 {
557 return NULL;
558 }
559
560 static inline struct module *__module_text_address(unsigned long addr)
561 {
562 return NULL;
563 }
564
565 static inline bool is_module_address(unsigned long addr)
566 {
567 return false;
568 }
569
570 static inline bool is_module_text_address(unsigned long addr)
571 {
572 return false;
573 }
574
575 /* Get/put a kernel symbol (calls should be symmetric) */
576 #define symbol_get(x) ({ extern typeof(x) x __attribute__((weak)); &(x); })
577 #define symbol_put(x) do { } while(0)
578 #define symbol_put_addr(x) do { } while(0)
579
580 static inline void __module_get(struct module *module)
581 {
582 }
583
584 static inline int try_module_get(struct module *module)
585 {
586 return 1;
587 }
588
589 static inline void module_put(struct module *module)
590 {
591 }
592
593 #define module_name(mod) "kernel"
594
595 /* For kallsyms to ask for address resolution. NULL means not found. */
596 static inline const char *module_address_lookup(unsigned long addr,
597 unsigned long *symbolsize,
598 unsigned long *offset,
599 char **modname,
600 char *namebuf)
601 {
602 return NULL;
603 }
604
605 static inline int lookup_module_symbol_name(unsigned long addr, char *symname)
606 {
607 return -ERANGE;
608 }
609
610 static inline int lookup_module_symbol_attrs(unsigned long addr, unsigned long *size, unsigned long *offset, char *modname, char *name)
611 {
612 return -ERANGE;
613 }
614
615 static inline int module_get_kallsym(unsigned int symnum, unsigned long *value,
616 char *type, char *name,
617 char *module_name, int *exported)
618 {
619 return -ERANGE;
620 }
621
622 static inline unsigned long module_kallsyms_lookup_name(const char *name)
623 {
624 return 0;
625 }
626
627 static inline int module_kallsyms_on_each_symbol(int (*fn)(void *, const char *,
628 struct module *,
629 unsigned long),
630 void *data)
631 {
632 return 0;
633 }
634
635 static inline int register_module_notifier(struct notifier_block * nb)
636 {
637 /* no events will happen anyway, so this can always succeed */
638 return 0;
639 }
640
641 static inline int unregister_module_notifier(struct notifier_block * nb)
642 {
643 return 0;
644 }
645
646 #define module_put_and_exit(code) do_exit(code)
647
648 static inline void print_modules(void)
649 {
650 }
651
652 static inline void module_update_tracepoints(void)
653 {
654 }
655
656 static inline int module_get_iter_tracepoints(struct tracepoint_iter *iter)
657 {
658 return 0;
659 }
660
661 #endif /* CONFIG_MODULES */
662
663 struct device_driver;
664 #ifdef CONFIG_SYSFS
665 struct module;
666
667 extern struct kset *module_kset;
668 extern struct kobj_type module_ktype;
669 extern int module_sysfs_initialized;
670
671 int mod_sysfs_init(struct module *mod);
672 int mod_sysfs_setup(struct module *mod,
673 struct kernel_param *kparam,
674 unsigned int num_params);
675 int module_add_modinfo_attrs(struct module *mod);
676 void module_remove_modinfo_attrs(struct module *mod);
677
678 #else /* !CONFIG_SYSFS */
679
680 static inline int mod_sysfs_init(struct module *mod)
681 {
682 return 0;
683 }
684
685 static inline int mod_sysfs_setup(struct module *mod,
686 struct kernel_param *kparam,
687 unsigned int num_params)
688 {
689 return 0;
690 }
691
692 static inline int module_add_modinfo_attrs(struct module *mod)
693 {
694 return 0;
695 }
696
697 static inline void module_remove_modinfo_attrs(struct module *mod)
698 { }
699
700 #endif /* CONFIG_SYSFS */
701
702 #define symbol_request(x) try_then_request_module(symbol_get(x), "symbol:" #x)
703
704 /* BELOW HERE ALL THESE ARE OBSOLETE AND WILL VANISH */
705
706 #define __MODULE_STRING(x) __stringify(x)
707
708
709 #ifdef CONFIG_GENERIC_BUG
710 int module_bug_finalize(const Elf_Ehdr *, const Elf_Shdr *,
711 struct module *);
712 void module_bug_cleanup(struct module *);
713
714 #else /* !CONFIG_GENERIC_BUG */
715
716 static inline int module_bug_finalize(const Elf_Ehdr *hdr,
717 const Elf_Shdr *sechdrs,
718 struct module *mod)
719 {
720 return 0;
721 }
722 static inline void module_bug_cleanup(struct module *mod) {}
723 #endif /* CONFIG_GENERIC_BUG */
724
725 #endif /* _LINUX_MODULE_H */