summaryrefslogtreecommitdiffstats
path: root/include/linux/module.h
blob: b653d7c0a05a0abbaf5e1b4759a3f79b398c8b25 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
#ifndef _LINUX_MODULE_H
#define _LINUX_MODULE_H
/*
 * Dynamic loading of modules into the kernel.
 *
 * Rewritten by Richard Henderson <rth@tamu.edu> Dec 1996
 * Rewritten again by Rusty Russell, 2002
 */
#include <linux/list.h>
#include <linux/stat.h>
#include <linux/compiler.h>
#include <linux/cache.h>
#include <linux/kmod.h>
#include <linux/elf.h>
#include <linux/stringify.h>
#include <linux/kobject.h>
#include <linux/moduleparam.h>
#include <linux/jump_label.h>
#include <linux/export.h>

#include <linux/percpu.h>
#include <asm/module.h>

/* In stripped ARM and x86-64 modules, ~ is surprisingly rare. */
#define MODULE_SIG_STRING "~Module signature appended~\n"

/* Not Yet Implemented */
#define MODULE_SUPPORTED_DEVICE(name)

#define MODULE_NAME_LEN MAX_PARAM_PREFIX_LEN

struct modversion_info {
	unsigned long crc;
	char name[MODULE_NAME_LEN];
};

struct module;

struct module_kobject {
	struct kobject kobj;
	struct module *mod;
	struct kobject *drivers_dir;
	struct module_param_attrs *mp;
	struct completion *kobj_completion;
};

struct module_attribute {
	struct attribute attr;
	ssize_t (*show)(struct module_attribute *, struct module_kobject *,
			char *);
	ssize_t (*store)(struct module_attribute *, struct module_kobject *,
			 const char *, size_t count);
	void (*setup)(struct module *, const char *);
	int (*test)(struct module *);
	void (*free)(struct module *);
};

struct module_version_attribute {
	struct module_attribute mattr;
	const char *module_name;
	const char *version;
} __attribute__ ((__aligned__(sizeof(void *))));

extern ssize_t __modver_version_show(struct module_attribute *,
				     struct module_kobject *, char *);

extern struct module_attribute module_uevent;

/* These are either module local, or the kernel's dummy ones. */
extern int init_module(void);
extern void cleanup_module(void);

/* Archs provide a method of finding the correct exception table. */
struct exception_table_entry;

const struct exception_table_entry *
search_extable(const struct exception_table_entry *first,
	       const struct exception_table_entry *last,
	       unsigned long value);
void sort_extable(struct exception_table_entry *start,
		  struct exception_table_entry *finish);
void sort_main_extable(void);
void trim_init_extable(struct module *m);

/* Generic info of form tag = "info" */
#define MODULE_INFO(tag, info) __MODULE_INFO(tag, tag, info)

/* For userspace: you can also call me... */
#define MODULE_ALIAS(_alias) MODULE_INFO(alias, _alias)

/* Soft module dependencies. See man modprobe.d for details.
 * Example: MODULE_SOFTDEP("pre: module-foo module-bar post: module-baz")
 */
#define MODULE_SOFTDEP(_softdep) MODULE_INFO(softdep, _softdep)

/*
 * The following license idents are currently accepted as indicating free
 * software modules
 *
 *	"GPL"				[GNU Public License v2 or later]
 *	"GPL v2"			[GNU Public License v2]
 *	"GPL and additional rights"	[GNU Public License v2 rights and more]
 *	"Dual BSD/GPL"			[GNU Public License v2
 *					 or BSD license choice]
 *	"Dual MIT/GPL"			[GNU Public License v2
 *					 or MIT license choice]
 *	"Dual MPL/GPL"			[GNU Public License v2
 *					 or Mozilla license choice]
 *
 * The following other idents are available
 *
 *	"Proprietary"			[Non free products]
 *
 * There are dual licensed components, but when running with Linux it is the
 * GPL that is relevant so this is a non issue. Similarly LGPL linked with GPL
 * is a GPL combined work.
 *
 * This exists for several reasons
 * 1.	So modinfo can show license info for users wanting to vet their setup
 *	is free
 * 2.	So the community can ignore bug reports including proprietary modules
 * 3.	So vendors can do likewise based on their own policies
 */
#define MODULE_LICENSE(_license) MODULE_INFO(license, _license)

/*
 * Author(s), use "Name <email>" or just "Name", for multiple
 * authors use multiple MODULE_AUTHOR() statements/lines.
 */
#define MODULE_AUTHOR(_author) MODULE_INFO(author, _author)

/* What your module does. */
#define MODULE_DESCRIPTION(_description) MODULE_INFO(description, _description)

#ifdef MODULE
/* Creates an alias so file2alias.c can find device table. */
#define MODULE_DEVICE_TABLE(type, name)					\
  extern const struct type##_device_id __mod_##type##__##name##_device_table \
  __attribute__ ((unused, alias(__stringify(name))))
#else  /* !MODULE */
#define MODULE_DEVICE_TABLE(type, name)
#endif

/* Version of form [<epoch>:]<version>[-<extra-version>].
 * Or for CVS/RCS ID version, everything but the number is stripped.
 * <epoch>: A (small) unsigned integer which allows you to start versions
 * anew. If not mentioned, it's zero.  eg. "2:1.0" is after
 * "1:2.0".

 * <version>: The <version> may contain only alphanumerics and the
 * character `.'.  Ordered by numeric sort for numeric parts,
 * ascii sort for ascii parts (as per RPM or DEB algorithm).

 * <extraversion>: Like <version>, but inserted for local
 * customizations, eg "rh3" or "rusty1".

 * Using this automatically adds a checksum of the .c files and the
 * local headers in "srcversion".
 */

#if defined(MODULE) || !defined(CONFIG_SYSFS)
#define MODULE_VERSION(_version) MODULE_INFO(version, _version)
#else
#define MODULE_VERSION(_version)					\
	static struct module_version_attribute ___modver_attr = {	\
		.mattr	= {						\
			.attr	= {					\
				.name	= "version",			\
				.mode	= S_IRUGO,			\
			},						\
			.show	= __modver_version_show,		\
		},							\
		.module_name	= KBUILD_MODNAME,			\
		.version	= _version,				\
	};								\
	static const struct module_version_attribute			\
	__used __attribute__ ((__section__ ("__modver")))		\
	* __moduleparam_const __modver_attr = &___modver_attr
#endif

/* Optional firmware file (or files) needed by the module
 * format is simply firmware file name.  Multiple firmware
 * files require multiple MODULE_FIRMWARE() specifiers */
#define MODULE_FIRMWARE(_firmware) MODULE_INFO(firmware, _firmware)

/* Given an address, look for it in the exception tables */
const struct exception_table_entry *search_exception_tables(unsigned long add);

struct notifier_block;

#ifdef CONFIG_MODULES

extern int modules_disabled; /* for sysctl */
/* Get/put a kernel symbol (calls must be symmetric) */
void *__symbol_get(const char *symbol);
void *__symbol_get_gpl(const char *symbol);
#define symbol_get(x) ((typeof(&x))(__symbol_get(VMLINUX_SYMBOL_STR(x))))

/* modules using other modules: kdb wants to see this. */
struct module_use {
	struct list_head source_list;
	struct list_head target_list;
	struct module *source, *target;
};

enum module_state {
	MODULE_STATE_LIVE,	/* Normal state. */
	MODULE_STATE_COMING,	/* Full formed, running module_init. */
	MODULE_STATE_GOING,	/* Going away. */
	MODULE_STATE_UNFORMED,	/* Still setting it up. */
};

struct module {
	enum module_state state;

	/* Member of list of modules */
	struct list_head list;

	/* Unique handle for this module */
	char name[MODULE_NAME_LEN];

	/* Sysfs stuff. */
	struct module_kobject mkobj;
	struct module_attribute *modinfo_attrs;
	const char *version;
	const char *srcversion;
	struct kobject *holders_dir;

	/* Exported symbols */
	const struct kernel_symbol *syms;
	const unsigned long *crcs;
	unsigned int num_syms;

	/* Kernel parameters. */
	struct kernel_param *kp;
	unsigned int num_kp;

	/* GPL-only exported symbols. */
	unsigned int num_gpl_syms;
	const struct kernel_symbol *gpl_syms;
	const unsigned long *gpl_crcs;

#ifdef CONFIG_UNUSED_SYMBOLS
	/* unused exported symbols. */
	const struct kernel_symbol *unused_syms;
	const unsigned long *unused_crcs;
	unsigned int num_unused_syms;

	/* GPL-only, unused exported symbols. */
	unsigned int num_unused_gpl_syms;
	const struct kernel_symbol *unused_gpl_syms;
	const unsigned long *unused_gpl_crcs;
#endif

#ifdef CONFIG_MODULE_SIG
	/* Signature was verified. */
	bool sig_ok;
#endif

	/* symbols that will be GPL-only in the near future. */
	const struct kernel_symbol *gpl_future_syms;
	const unsigned long *gpl_future_crcs;
	unsigned int num_gpl_future_syms;

	/* Exception table */
	unsigned int num_exentries;
	struct exception_table_entry *extable;

	/* Startup function. */
	int (*init)(void);

	/* If this is non-NULL, vfree after init() returns */
	void *module_init;

	/* Here is the actual code + data, vfree'd on unload. */
	void *module_core;

	/* Here are the sizes of the init and core sections */
	unsigned int init_size, core_size;

	/* The size of the executable code in each section.  */
	unsigned int init_text_size, core_text_size;

	/* Size of RO sections of the module (text+rodata) */
	unsigned int init_ro_size, core_ro_size;

	/* Arch-specific module values */
	struct mod_arch_specific arch;

	unsigned int taints;	/* same bits as kernel:tainted */

#ifdef CONFIG_GENERIC_BUG
	/* Support for BUG */
	unsigned num_bugs;
	struct list_head bug_list;
	struct bug_entry *bug_table;
#endif

#ifdef CONFIG_KALLSYMS
	/*
	 * We keep the symbol and string tables for kallsyms.
	 * The core_* fields below are temporary, loader-only (they
	 * could really be discarded after module init).
	 */
	Elf_Sym *symtab, *core_symtab;
	unsigned int num_symtab, core_num_syms;
	char *strtab, *core_strtab;

	/* Section attributes */
	struct module_sect_attrs *sect_attrs;

	/* Notes attributes */
	struct module_notes_attrs *notes_attrs;
#endif

	/* The command line arguments (may be mangled).  People like
	   keeping pointers to this stuff */
	char *args;

#ifdef CONFIG_SMP
	/* Per-cpu data. */
	void __percpu *percpu;
	unsigned int percpu_size;
#endif

#ifdef CONFIG_TRACEPOINTS
	unsigned int num_tracepoints;
	struct tracepoint * const *tracepoints_ptrs;
#endif
#ifdef HAVE_JUMP_LABEL
	struct jump_entry *jump_entries;
	unsigned int num_jump_entries;
#endif
#ifdef CONFIG_TRACING
	unsigned int num_trace_bprintk_fmt;
	const char **trace_bprintk_fmt_start;
#endif
#ifdef CONFIG_EVENT_TRACING
	struct ftrace_event_call **trace_events;
	unsigned int num_trace_events;
#endif
#ifdef CONFIG_FTRACE_MCOUNT_RECORD
	unsigned int num_ftrace_callsites;
	unsigned long *ftrace_callsites;
#endif

#ifdef CONFIG_MODULE_UNLOAD
	/* What modules depend on me? */
	struct list_head source_list;
	/* What modules do I depend on? */
	struct list_head target_list;

	/* Destruction function. */
	void (*exit)(void);

	atomic_t refcnt;
#endif

#ifdef CONFIG_CONSTRUCTORS
	/* Constructor functions. */
	ctor_fn_t *ctors;
	unsigned int num_ctors;
#endif
};
#ifndef MODULE_ARCH_INIT
#define MODULE_ARCH_INIT {}
#endif

extern struct mutex module_mutex;

/* FIXME: It'd be nice to isolate modules during init, too, so they
   aren't used before they (may) fail.  But presently too much code
   (IDE & SCSI) require entry into the module during init.*/
static inline int module_is_live(struct module *mod)
{
	return mod->state != MODULE_STATE_GOING;
}

struct module *__module_text_address(unsigned long addr);
struct module *__module_address(unsigned long addr);
bool is_module_address(unsigned long addr);
bool is_module_percpu_address(unsigned long addr);
bool is_module_text_address(unsigned long addr);

static inline bool within_module_core(unsigned long addr,
				      const struct module *mod)
{
	return (unsigned long)mod->module_core <= addr &&
	       addr < (unsigned long)mod->module_core + mod->core_size;
}

static inline bool within_module_init(unsigned long addr,
				      const struct module *mod)
{
	return (unsigned long)mod->module_init <= addr &&
	       addr < (unsigned long)mod->module_init + mod->init_size;
}

static inline bool within_module(unsigned long addr, const struct module *mod)
{
	return within_module_init(addr, mod) || within_module_core(addr, mod);
}

/* Search for module by name: must hold module_mutex. */
struct module *find_module(const char *name);

struct symsearch {
	const struct kernel_symbol *start, *stop;
	const unsigned long *crcs;
	enum {
		NOT_GPL_ONLY,
		GPL_ONLY,
		WILL_BE_GPL_ONLY,
	} licence;
	bool unused;
};

/* Search for an exported symbol by name. */
const struct kernel_symbol *find_symbol(const char *name,
					struct module **owner,
					const unsigned long **crc,
					bool gplok,
					bool warn);

/* Walk the exported symbol table */
bool each_symbol_section(bool (*fn)(const struct symsearch *arr,
				    struct module *owner,
				    void *data), void *data);

/* Returns 0 and fills in value, defined and namebuf, or -ERANGE if
   symnum out of range. */
int module_get_kallsym(unsigned int symnum, unsigned long *value, char *type,
			char *name, char *module_name, int *exported);

/* Look for this name: can be of form module:name. */
unsigned long module_kallsyms_lookup_name(const char *name);

int module_kallsyms_on_each_symbol(int (*fn)(void *, const char *,
					     struct module *, unsigned long),
				   void *data);

extern void __module_put_and_exit(struct module *mod, long code)
	__attribute__((noreturn));
#define module_put_and_exit(code) __module_put_and_exit(THIS_MODULE, code)

#ifdef CONFIG_MODULE_UNLOAD
int module_refcount(struct module *mod);
void __symbol_put(const char *symbol);
#define symbol_put(x) __symbol_put(VMLINUX_SYMBOL_STR(x))
void symbol_put_addr(void *addr);

/* Sometimes we know we already have a refcount, and it's easier not
   to handle the error case (which only happens with rmmod --wait). */
extern void __module_get(struct module *module);

/* This is the Right Way to get a module: if it fails, it's being removed,
 * so pretend it's not there. */
extern bool try_module_get(struct module *module);

extern void module_put(struct module *module);

#else /*!CONFIG_MODULE_UNLOAD*/
static inline int try_module_get(struct module *module)
{
	return !module || module_is_live(module);
}
static inline void module_put(struct module *module)
{
}
static inline void __module_get(struct module *module)
{
}
#define symbol_put(x) do { } while (0)
#define symbol_put_addr(p) do { } while (0)

#endif /* CONFIG_MODULE_UNLOAD */
int ref_module(struct module *a, struct module *b);

/* This is a #define so the string doesn't get put in every .o file */
#define module_name(mod)			\
({						\
	struct module *__mod = (mod);		\
	__mod ? __mod->name : "kernel";		\
})

/* For kallsyms to ask for address resolution.  namebuf should be at
 * least KSYM_NAME_LEN long: a pointer to namebuf is returned if
 * found, otherwise NULL. */
const char *module_address_lookup(unsigned long addr,
			    unsigned long *symbolsize,
			    unsigned long *offset,
			    char **modname,
			    char *namebuf);
int lookup_module_symbol_name(unsigned long addr, char *symname);
int lookup_module_symbol_attrs(unsigned long addr, unsigned long *size, unsigned long *offset, char *modname, char *name);

/* For extable.c to search modules' exception tables. */
const struct exception_table_entry *search_module_extables(unsigned long addr);

int register_module_notifier(struct notifier_block *nb);
int unregister_module_notifier(struct notifier_block *nb);

extern void print_modules(void);

#else /* !CONFIG_MODULES... */

/* Given an address, look for it in the exception tables. */
static inline const struct exception_table_entry *
search_module_extables(unsigned long addr)
{
	return NULL;
}

static inline struct module *__module_address(unsigned long addr)
{
	return NULL;
}

static inline struct module *__module_text_address(unsigned long addr)
{
	return NULL;
}

static inline bool is_module_address(unsigned long addr)
{
	return false;
}

static inline bool is_module_percpu_address(unsigned long addr)
{
	return false;
}

static inline bool is_module_text_address(unsigned long addr)
{
	return false;
}

/* Get/put a kernel symbol (calls should be symmetric) */
#define symbol_get(x) ({ extern typeof(x) x __attribute__((weak)); &(x); })
#define symbol_put(x) do { } while (0)
#define symbol_put_addr(x) do { } while (0)

static inline void __module_get(struct module *module)
{
}

static inline int try_module_get(struct module *module)
{
	return 1;
}

static inline void module_put(struct module *module)
{
}

#define module_name(mod) "kernel"

/* For kallsyms to ask for address resolution.  NULL means not found. */
static inline const char *module_address_lookup(unsigned long addr,
					  unsigned long *symbolsize,
					  unsigned long *offset,
					  char **modname,
					  char *namebuf)
{
	return NULL;
}

static inline int lookup_module_symbol_name(unsigned long addr, char *symname)
{
	return -ERANGE;
}

static inline int lookup_module_symbol_attrs(unsigned long addr, unsigned long *size, unsigned long *offset, char *modname, char *name)
{
	return -ERANGE;
}

static inline int module_get_kallsym(unsigned int symnum, unsigned long *value,
					char *type, char *name,
					char *module_name, int *exported)
{
	return -ERANGE;
}

static inline unsigned long module_kallsyms_lookup_name(const char *name)
{
	return 0;
}

static inline int module_kallsyms_on_each_symbol(int (*fn)(void *, const char *,
							   struct module *,
							   unsigned long),
						 void *data)
{
	return 0;
}

static inline int register_module_notifier(struct notifier_block *nb)
{
	/* no events will happen anyway, so this can always succeed */
	return 0;
}

static inline int unregister_module_notifier(struct notifier_block *nb)
{
	return 0;
}

#define module_put_and_exit(code) do_exit(code)

static inline void print_modules(void)
{
}
#endif /* CONFIG_MODULES */

#ifdef CONFIG_SYSFS
extern struct kset *module_kset;
extern struct kobj_type module_ktype;
extern int module_sysfs_initialized;
#endif /* CONFIG_SYSFS */

#define symbol_request(x) try_then_request_module(symbol_get(x), "symbol:" #x)

/* BELOW HERE ALL THESE ARE OBSOLETE AND WILL VANISH */

#define __MODULE_STRING(x) __stringify(x)

#ifdef CONFIG_DEBUG_SET_MODULE_RONX
extern void set_all_modules_text_rw(void);
extern void set_all_modules_text_ro(void);
#else
static inline void set_all_modules_text_rw(void) { }
static inline void set_all_modules_text_ro(void) { }
#endif

#ifdef CONFIG_GENERIC_BUG
void module_bug_finalize(const Elf_Ehdr *, const Elf_Shdr *,
			 struct module *);
void module_bug_cleanup(struct module *);

#else	/* !CONFIG_GENERIC_BUG */

static inline void module_bug_finalize(const Elf_Ehdr *hdr,
					const Elf_Shdr *sechdrs,
					struct module *mod)
{
}
static inline void module_bug_cleanup(struct module *mod) {}
#endif	/* CONFIG_GENERIC_BUG */

#endif /* _LINUX_MODULE_H */