Free Electrons

Embedded Linux Experts

  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
#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/marker.h>
#include <asm/local.h>

#include <asm/module.h>

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

/* v850 toolchain uses a `_' prefix for all user symbols */
#ifndef MODULE_SYMBOL_PREFIX
#define MODULE_SYMBOL_PREFIX ""
#endif

#define MODULE_NAME_LEN (64 - sizeof(unsigned long))

struct kernel_symbol
{
	unsigned long value;
	const char *name;
};

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

struct module;

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

struct module_kobject
{
	struct kobject kobj;
	struct module *mod;
	struct kobject *drivers_dir;
};

/* 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);

#ifdef MODULE
#define MODULE_GENERIC_TABLE(gtype,name)			\
extern const struct gtype##_id __mod_##gtype##_table		\
  __attribute__ ((unused, alias(__stringify(name))))

extern struct module __this_module;
#define THIS_MODULE (&__this_module)
#else  /* !MODULE */
#define MODULE_GENERIC_TABLE(gtype,name)
#define THIS_MODULE ((struct module *)0)
#endif

/* 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)

/*
 * 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, ideally of form NAME[, NAME]*[ and NAME] */
#define MODULE_AUTHOR(_author) MODULE_INFO(author, _author)
  
/* What your module does. */
#define MODULE_DESCRIPTION(_description) MODULE_INFO(description, _description)

/* One for each parameter, describing how to use it.  Some files do
   multiple of these per line, so can't just use MODULE_INFO. */
#define MODULE_PARM_DESC(_parm, desc) \
	__MODULE_INFO(parm, _parm, #_parm ":" desc)

#define MODULE_DEVICE_TABLE(type,name)		\
  MODULE_GENERIC_TABLE(type##_device,name)

/* 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".
*/
#define MODULE_VERSION(_version) MODULE_INFO(version, _version)

/* 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

/* 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(MODULE_SYMBOL_PREFIX #x)))

#ifndef __GENKSYMS__
#ifdef CONFIG_MODVERSIONS
/* Mark the CRC weak since genksyms apparently decides not to
 * generate a checksums for some symbols */
#define __CRC_SYMBOL(sym, sec)					\
	extern void *__crc_##sym __attribute__((weak));		\
	static const unsigned long __kcrctab_##sym		\
	__used							\
	__attribute__((section("__kcrctab" sec), unused))	\
	= (unsigned long) &__crc_##sym;
#else
#define __CRC_SYMBOL(sym, sec)
#endif

/* For every exported symbol, place a struct in the __ksymtab section */
#define __EXPORT_SYMBOL(sym, sec)				\
	extern typeof(sym) sym;					\
	__CRC_SYMBOL(sym, sec)					\
	static const char __kstrtab_##sym[]			\
	__attribute__((section("__ksymtab_strings")))		\
	= MODULE_SYMBOL_PREFIX #sym;                    	\
	static const struct kernel_symbol __ksymtab_##sym	\
	__used							\
	__attribute__((section("__ksymtab" sec), unused))	\
	= { (unsigned long)&sym, __kstrtab_##sym }

#define EXPORT_SYMBOL(sym)					\
	__EXPORT_SYMBOL(sym, "")

#define EXPORT_SYMBOL_GPL(sym)					\
	__EXPORT_SYMBOL(sym, "_gpl")

#define EXPORT_SYMBOL_GPL_FUTURE(sym)				\
	__EXPORT_SYMBOL(sym, "_gpl_future")


#ifdef CONFIG_UNUSED_SYMBOLS
#define EXPORT_UNUSED_SYMBOL(sym) __EXPORT_SYMBOL(sym, "_unused")
#define EXPORT_UNUSED_SYMBOL_GPL(sym) __EXPORT_SYMBOL(sym, "_unused_gpl")
#else
#define EXPORT_UNUSED_SYMBOL(sym)
#define EXPORT_UNUSED_SYMBOL_GPL(sym)
#endif

#endif

struct module_ref
{
	local_t count;
} ____cacheline_aligned;

enum module_state
{
	MODULE_STATE_LIVE,
	MODULE_STATE_COMING,
	MODULE_STATE_GOING,
};

/* Similar stuff for section attributes. */
struct module_sect_attr
{
	struct module_attribute mattr;
	char *name;
	unsigned long address;
};

struct module_sect_attrs
{
	struct attribute_group grp;
	int nsections;
	struct module_sect_attr attrs[0];
};

struct module_param_attrs;

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_param_attrs *param_attrs;
	struct module_attribute *modinfo_attrs;
	const char *version;
	const char *srcversion;
	struct kobject *holders_dir;

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

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

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

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

	/* Exception table */
	unsigned int num_exentries;
	const 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 long init_size, core_size;

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

	/* The handle returned from unwind_add_table. */
	void *unwind_info;

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

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

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

#ifdef CONFIG_MODULE_UNLOAD
	/* Reference counts */
	struct module_ref ref[NR_CPUS];

	/* What modules depend on me? */
	struct list_head modules_which_use_me;

	/* Who is waiting for us to be unloaded */
	struct task_struct *waiter;

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

#ifdef CONFIG_KALLSYMS
	/* We keep the symbol and string tables for kallsyms. */
	Elf_Sym *symtab;
	unsigned long num_symtab;
	char *strtab;

	/* Section attributes */
	struct module_sect_attrs *sect_attrs;

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

	/* Per-cpu data. */
	void *percpu;

	/* The command line arguments (may be mangled).  People like
	   keeping pointers to this stuff */
	char *args;
#ifdef CONFIG_MARKERS
	struct marker *markers;
	unsigned int num_markers;
#endif
};
#ifndef MODULE_ARCH_INIT
#define MODULE_ARCH_INIT {}
#endif

/* 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;
}

/* Is this address in a module? (second is with no locks, for oops) */
struct module *module_text_address(unsigned long addr);
struct module *__module_text_address(unsigned long addr);
int is_module_address(unsigned long addr);

/* 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);

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
unsigned int module_refcount(struct module *mod);
void __symbol_put(const char *symbol);
#define symbol_put(x) __symbol_put(MODULE_SYMBOL_PREFIX #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). */
static inline void __module_get(struct module *module)
{
	if (module) {
		BUG_ON(module_refcount(module) == 0);
		local_inc(&module->ref[get_cpu()].count);
		put_cpu();
	}
}

static inline int try_module_get(struct module *module)
{
	int ret = 1;

	if (module) {
		unsigned int cpu = get_cpu();
		if (likely(module_is_live(module)))
			local_inc(&module->ref[cpu].count);
		else
			ret = 0;
		put_cpu();
	}
	return ret;
}

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 */

/* 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);

extern void module_update_markers(void);

#else /* !CONFIG_MODULES... */
#define EXPORT_SYMBOL(sym)
#define EXPORT_SYMBOL_GPL(sym)
#define EXPORT_SYMBOL_GPL_FUTURE(sym)
#define EXPORT_UNUSED_SYMBOL(sym)
#define EXPORT_UNUSED_SYMBOL_GPL(sym)

/* 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;
}

/* Is this address in a module? */
static inline struct module *module_text_address(unsigned long addr)
{
	return NULL;
}

/* Is this address in a module? (don't take a lock, we're oopsing) */
static inline struct module *__module_text_address(unsigned long addr)
{
	return NULL;
}

static inline int is_module_address(unsigned long addr)
{
	return 0;
}

/* 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 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)
{
}

static inline void module_update_markers(void)
{
}

#endif /* CONFIG_MODULES */

struct device_driver;
#ifdef CONFIG_SYSFS
struct module;

extern struct kset *module_kset;
extern struct kobj_type module_ktype;
extern int module_sysfs_initialized;

int mod_sysfs_init(struct module *mod);
int mod_sysfs_setup(struct module *mod,
			   struct kernel_param *kparam,
			   unsigned int num_params);
int module_add_modinfo_attrs(struct module *mod);
void module_remove_modinfo_attrs(struct module *mod);

#else /* !CONFIG_SYSFS */

static inline int mod_sysfs_init(struct module *mod)
{
	return 0;
}

static inline int mod_sysfs_setup(struct module *mod,
			   struct kernel_param *kparam,
			   unsigned int num_params)
{
	return 0;
}

static inline int module_add_modinfo_attrs(struct module *mod)
{
	return 0;
}

static inline void module_remove_modinfo_attrs(struct module *mod)
{ }

#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)

#endif /* _LINUX_MODULE_H */