xref: /linux/include/linux/module.h (revision 88b29f3f579987fff0d2bd726d5fa95a53f857fa)
1 /* SPDX-License-Identifier: GPL-2.0-only */
2 /*
3  * Dynamic loading of modules into the kernel.
4  *
5  * Rewritten by Richard Henderson <rth@tamu.edu> Dec 1996
6  * Rewritten again by Rusty Russell, 2002
7  */
8 
9 #ifndef _LINUX_MODULE_H
10 #define _LINUX_MODULE_H
11 
12 #include <linux/list.h>
13 #include <linux/stat.h>
14 #include <linux/buildid.h>
15 #include <linux/compiler.h>
16 #include <linux/cache.h>
17 #include <linux/cleanup.h>
18 #include <linux/kmod.h>
19 #include <linux/init.h>
20 #include <linux/elf.h>
21 #include <linux/stringify.h>
22 #include <linux/kobject.h>
23 #include <linux/moduleparam.h>
24 #include <linux/jump_label.h>
25 #include <linux/export.h>
26 #include <linux/rbtree_latch.h>
27 #include <linux/error-injection.h>
28 #include <linux/tracepoint-defs.h>
29 #include <linux/srcu.h>
30 #include <linux/static_call_types.h>
31 #include <linux/dynamic_debug.h>
32 
33 #include <linux/percpu.h>
34 #include <asm/module.h>
35 
36 #define MODULE_NAME_LEN __MODULE_NAME_LEN
37 
38 struct modversion_info {
39 	unsigned long crc;
40 	char name[MODULE_NAME_LEN];
41 };
42 
43 struct module;
44 struct exception_table_entry;
45 
46 struct module_kobject {
47 	struct kobject kobj;
48 	struct module *mod;
49 	struct kobject *drivers_dir;
50 	struct module_param_attrs *mp;
51 	struct completion *kobj_completion;
52 } __randomize_layout;
53 
54 struct module_attribute {
55 	struct attribute attr;
56 	ssize_t (*show)(const struct module_attribute *, struct module_kobject *,
57 			char *);
58 	ssize_t (*store)(const struct module_attribute *, struct module_kobject *,
59 			 const char *, size_t count);
60 	void (*setup)(struct module *, const char *);
61 	int (*test)(struct module *);
62 	void (*free)(struct module *);
63 };
64 
65 struct module_version_attribute {
66 	struct module_attribute mattr;
67 	const char *module_name;
68 	const char *version;
69 };
70 
71 extern ssize_t __modver_version_show(const struct module_attribute *,
72 				     struct module_kobject *, char *);
73 
74 extern const struct module_attribute module_uevent;
75 
76 /* These are either module local, or the kernel's dummy ones. */
77 extern int init_module(void);
78 extern void cleanup_module(void);
79 
80 #ifndef MODULE
81 /**
82  * module_init() - driver initialization entry point
83  * @x: function to be run at kernel boot time or module insertion
84  *
85  * module_init() will either be called during do_initcalls() (if
86  * builtin) or at module insertion time (if a module).  There can only
87  * be one per module.
88  */
89 #define module_init(x)	__initcall(x);
90 
91 /**
92  * module_exit() - driver exit entry point
93  * @x: function to be run when driver is removed
94  *
95  * module_exit() will wrap the driver clean-up code
96  * with cleanup_module() when used with rmmod when
97  * the driver is a module.  If the driver is statically
98  * compiled into the kernel, module_exit() has no effect.
99  * There can only be one per module.
100  */
101 #define module_exit(x)	__exitcall(x);
102 
103 #else /* MODULE */
104 
105 /*
106  * In most cases loadable modules do not need custom
107  * initcall levels. There are still some valid cases where
108  * a driver may be needed early if built in, and does not
109  * matter when built as a loadable module. Like bus
110  * snooping debug drivers.
111  */
112 #define early_initcall(fn)		module_init(fn)
113 #define core_initcall(fn)		module_init(fn)
114 #define core_initcall_sync(fn)		module_init(fn)
115 #define postcore_initcall(fn)		module_init(fn)
116 #define postcore_initcall_sync(fn)	module_init(fn)
117 #define arch_initcall(fn)		module_init(fn)
118 #define subsys_initcall(fn)		module_init(fn)
119 #define subsys_initcall_sync(fn)	module_init(fn)
120 #define fs_initcall(fn)			module_init(fn)
121 #define fs_initcall_sync(fn)		module_init(fn)
122 #define rootfs_initcall(fn)		module_init(fn)
123 #define device_initcall(fn)		module_init(fn)
124 #define device_initcall_sync(fn)	module_init(fn)
125 #define late_initcall(fn)		module_init(fn)
126 #define late_initcall_sync(fn)		module_init(fn)
127 
128 #define console_initcall(fn)		module_init(fn)
129 
130 /* Each module must use one module_init(). */
131 #define module_init(initfn)					\
132 	static inline initcall_t __maybe_unused __inittest(void)		\
133 	{ return initfn; }					\
134 	int init_module(void) __copy(initfn)			\
135 		__attribute__((alias(#initfn)));		\
136 	___ADDRESSABLE(init_module, __initdata);
137 
138 /* This is only required if you want to be unloadable. */
139 #define module_exit(exitfn)					\
140 	static inline exitcall_t __maybe_unused __exittest(void)		\
141 	{ return exitfn; }					\
142 	void cleanup_module(void) __copy(exitfn)		\
143 		__attribute__((alias(#exitfn)));		\
144 	___ADDRESSABLE(cleanup_module, __exitdata);
145 
146 #endif
147 
148 /* This means "can be init if no module support, otherwise module load
149    may call it." */
150 #ifdef CONFIG_MODULES
151 #define __init_or_module
152 #define __initdata_or_module
153 #define __initconst_or_module
154 #else
155 #define __init_or_module __init
156 #define __initdata_or_module __initdata
157 #define __initconst_or_module __initconst
158 #endif /*CONFIG_MODULES*/
159 
160 struct module_kobject *lookup_or_create_module_kobject(const char *name);
161 
162 /* For userspace: you can also call me... */
163 #define MODULE_ALIAS(_alias) MODULE_INFO(alias, _alias)
164 
165 /* Soft module dependencies. See man modprobe.d for details.
166  * Example: MODULE_SOFTDEP("pre: module-foo module-bar post: module-baz")
167  */
168 #define MODULE_SOFTDEP(_softdep) MODULE_INFO(softdep, _softdep)
169 
170 /*
171  * Weak module dependencies. See man modprobe.d for details.
172  * Example: MODULE_WEAKDEP("module-foo")
173  */
174 #define MODULE_WEAKDEP(_weakdep) MODULE_INFO(weakdep, _weakdep)
175 
176 /*
177  * MODULE_FILE is used for generating modules.builtin
178  * So, make it no-op when this is being built as a module
179  */
180 #ifdef MODULE
181 #define MODULE_FILE
182 #else
183 #define MODULE_FILE	MODULE_INFO(file, KBUILD_MODFILE);
184 #endif
185 
186 /*
187  * The following license idents are currently accepted as indicating free
188  * software modules
189  *
190  *	"GPL"				[GNU Public License v2]
191  *	"GPL v2"			[GNU Public License v2]
192  *	"GPL and additional rights"	[GNU Public License v2 rights and more]
193  *	"Dual BSD/GPL"			[GNU Public License v2
194  *					 or BSD license choice]
195  *	"Dual MIT/GPL"			[GNU Public License v2
196  *					 or MIT license choice]
197  *	"Dual MPL/GPL"			[GNU Public License v2
198  *					 or Mozilla license choice]
199  *
200  * The following other idents are available
201  *
202  *	"Proprietary"			[Non free products]
203  *
204  * Both "GPL v2" and "GPL" (the latter also in dual licensed strings) are
205  * merely stating that the module is licensed under the GPL v2, but are not
206  * telling whether "GPL v2 only" or "GPL v2 or later". The reason why there
207  * are two variants is a historic and failed attempt to convey more
208  * information in the MODULE_LICENSE string. For module loading the
209  * "only/or later" distinction is completely irrelevant and does neither
210  * replace the proper license identifiers in the corresponding source file
211  * nor amends them in any way. The sole purpose is to make the
212  * 'Proprietary' flagging work and to refuse to bind symbols which are
213  * exported with EXPORT_SYMBOL_GPL when a non free module is loaded.
214  *
215  * In the same way "BSD" is not a clear license information. It merely
216  * states, that the module is licensed under one of the compatible BSD
217  * license variants. The detailed and correct license information is again
218  * to be found in the corresponding source files.
219  *
220  * There are dual licensed components, but when running with Linux it is the
221  * GPL that is relevant so this is a non issue. Similarly LGPL linked with GPL
222  * is a GPL combined work.
223  *
224  * This exists for several reasons
225  * 1.	So modinfo can show license info for users wanting to vet their setup
226  *	is free
227  * 2.	So the community can ignore bug reports including proprietary modules
228  * 3.	So vendors can do likewise based on their own policies
229  */
230 #define MODULE_LICENSE(_license) MODULE_FILE MODULE_INFO(license, _license)
231 
232 /*
233  * Author(s), use "Name <email>" or just "Name", for multiple
234  * authors use multiple MODULE_AUTHOR() statements/lines.
235  */
236 #define MODULE_AUTHOR(_author) MODULE_INFO(author, _author)
237 
238 /* What your module does. */
239 #define MODULE_DESCRIPTION(_description) MODULE_INFO(description, _description)
240 
241 /*
242  * Format: __mod_device_table__kmod_<modname>__<type>__<name>
243  * Parts of the string `__kmod_` and `__` are used as delimiters when parsing
244  * a symbol in file2alias.c
245  */
246 #define __mod_device_table(type, name)	\
247 	__PASTE(__mod_device_table__,	\
248 	__PASTE(kmod_,			\
249 	__PASTE(__KBUILD_MODNAME,	\
250 	__PASTE(__,			\
251 	__PASTE(type,			\
252 	__PASTE(__, name))))))
253 
254 /* Creates an alias so file2alias.c can find device table. */
255 #define MODULE_DEVICE_TABLE(type, name)					\
256 static typeof(name) __mod_device_table(type, name)			\
257   __attribute__ ((used, alias(__stringify(name))))
258 
259 /* Version of form [<epoch>:]<version>[-<extra-version>].
260  * Or for CVS/RCS ID version, everything but the number is stripped.
261  * <epoch>: A (small) unsigned integer which allows you to start versions
262  * anew. If not mentioned, it's zero.  eg. "2:1.0" is after
263  * "1:2.0".
264 
265  * <version>: The <version> may contain only alphanumerics and the
266  * character `.'.  Ordered by numeric sort for numeric parts,
267  * ascii sort for ascii parts (as per RPM or DEB algorithm).
268 
269  * <extraversion>: Like <version>, but inserted for local
270  * customizations, eg "rh3" or "rusty1".
271 
272  * Using this automatically adds a checksum of the .c files and the
273  * local headers in "srcversion".
274  */
275 
276 #if defined(MODULE) || !defined(CONFIG_SYSFS)
277 #define MODULE_VERSION(_version) MODULE_INFO(version, _version)
278 #else
279 #define MODULE_VERSION(_version)					\
280 	MODULE_INFO(version, _version);					\
281 	static const struct module_version_attribute __modver_attr	\
282 		__used __section("__modver")				\
283 		__aligned(__alignof__(struct module_version_attribute)) \
284 		= {							\
285 			.mattr	= {					\
286 				.attr	= {				\
287 					.name	= "version",		\
288 					.mode	= S_IRUGO,		\
289 				},					\
290 				.show	= __modver_version_show,	\
291 			},						\
292 			.module_name	= KBUILD_MODNAME,		\
293 			.version	= _version,			\
294 		}
295 #endif
296 
297 /* Optional firmware file (or files) needed by the module
298  * format is simply firmware file name.  Multiple firmware
299  * files require multiple MODULE_FIRMWARE() specifiers */
300 #define MODULE_FIRMWARE(_firmware) MODULE_INFO(firmware, _firmware)
301 
302 #define MODULE_IMPORT_NS(ns)	MODULE_INFO(import_ns, ns)
303 
304 struct notifier_block;
305 
306 enum module_state {
307 	MODULE_STATE_LIVE,	/* Normal state. */
308 	MODULE_STATE_COMING,	/* Full formed, running module_init. */
309 	MODULE_STATE_GOING,	/* Going away. */
310 	MODULE_STATE_UNFORMED,	/* Still setting it up. */
311 };
312 
313 struct mod_tree_node {
314 	struct module *mod;
315 	struct latch_tree_node node;
316 };
317 
318 enum mod_mem_type {
319 	MOD_TEXT = 0,
320 	MOD_DATA,
321 	MOD_RODATA,
322 	MOD_RO_AFTER_INIT,
323 	MOD_INIT_TEXT,
324 	MOD_INIT_DATA,
325 	MOD_INIT_RODATA,
326 
327 	MOD_MEM_NUM_TYPES,
328 	MOD_INVALID = -1,
329 };
330 
331 #define mod_mem_type_is_init(type)	\
332 	((type) == MOD_INIT_TEXT ||	\
333 	 (type) == MOD_INIT_DATA ||	\
334 	 (type) == MOD_INIT_RODATA)
335 
336 #define mod_mem_type_is_core(type) (!mod_mem_type_is_init(type))
337 
338 #define mod_mem_type_is_text(type)	\
339 	 ((type) == MOD_TEXT ||		\
340 	  (type) == MOD_INIT_TEXT)
341 
342 #define mod_mem_type_is_data(type) (!mod_mem_type_is_text(type))
343 
344 #define mod_mem_type_is_core_data(type)	\
345 	(mod_mem_type_is_core(type) &&	\
346 	 mod_mem_type_is_data(type))
347 
348 #define for_each_mod_mem_type(type)			\
349 	for (enum mod_mem_type (type) = 0;		\
350 	     (type) < MOD_MEM_NUM_TYPES; (type)++)
351 
352 #define for_class_mod_mem_type(type, class)		\
353 	for_each_mod_mem_type(type)			\
354 		if (mod_mem_type_is_##class(type))
355 
356 struct module_memory {
357 	void *base;
358 	bool is_rox;
359 	unsigned int size;
360 
361 #ifdef CONFIG_MODULES_TREE_LOOKUP
362 	struct mod_tree_node mtn;
363 #endif
364 };
365 
366 #ifdef CONFIG_MODULES_TREE_LOOKUP
367 /* Only touch one cacheline for common rbtree-for-core-layout case. */
368 #define __module_memory_align ____cacheline_aligned
369 #else
370 #define __module_memory_align
371 #endif
372 
373 struct mod_kallsyms {
374 	Elf_Sym *symtab;
375 	unsigned int num_symtab;
376 	char *strtab;
377 	char *typetab;
378 };
379 
380 #ifdef CONFIG_LIVEPATCH
381 /**
382  * struct klp_modinfo - ELF information preserved from the livepatch module
383  *
384  * @hdr: ELF header
385  * @sechdrs: Section header table
386  * @secstrings: String table for the section headers
387  * @symndx: The symbol table section index
388  */
389 struct klp_modinfo {
390 	Elf_Ehdr hdr;
391 	Elf_Shdr *sechdrs;
392 	char *secstrings;
393 	unsigned int symndx;
394 };
395 #endif
396 
397 struct module {
398 	enum module_state state;
399 
400 	/* Member of list of modules */
401 	struct list_head list;
402 
403 	/* Unique handle for this module */
404 	char name[MODULE_NAME_LEN];
405 
406 #ifdef CONFIG_STACKTRACE_BUILD_ID
407 	/* Module build ID */
408 	unsigned char build_id[BUILD_ID_SIZE_MAX];
409 #endif
410 
411 	/* Sysfs stuff. */
412 	struct module_kobject mkobj;
413 	struct module_attribute *modinfo_attrs;
414 	const char *version;
415 	const char *srcversion;
416 	const char *imported_namespaces;
417 	struct kobject *holders_dir;
418 
419 	/* Exported symbols */
420 	const struct kernel_symbol *syms;
421 	const u32 *crcs;
422 	const u8 *flagstab;
423 	unsigned int num_syms;
424 
425 #ifdef CONFIG_ARCH_USES_CFI_TRAPS
426 	s32 *kcfi_traps;
427 	s32 *kcfi_traps_end;
428 #endif
429 
430 	/* Kernel parameters. */
431 #ifdef CONFIG_SYSFS
432 	struct mutex param_lock;
433 #endif
434 	struct kernel_param *kp;
435 	unsigned int num_kp;
436 
437 	/* GPL-only exported symbols. */
438 	bool using_gplonly_symbols;
439 
440 #ifdef CONFIG_MODULE_SIG
441 	/* Signature was verified. */
442 	bool sig_ok;
443 #endif
444 
445 	bool async_probe_requested;
446 
447 	/* Exception table */
448 	unsigned int num_exentries;
449 	struct exception_table_entry *extable;
450 
451 	/* Startup function. */
452 	int (*init)(void);
453 
454 	struct module_memory mem[MOD_MEM_NUM_TYPES] __module_memory_align;
455 
456 	/* Arch-specific module values */
457 	struct mod_arch_specific arch;
458 
459 	unsigned long taints;	/* same bits as kernel:taint_flags */
460 
461 #ifdef CONFIG_GENERIC_BUG
462 	/* Support for BUG */
463 	unsigned num_bugs;
464 	struct list_head bug_list;
465 	struct bug_entry *bug_table;
466 #endif
467 
468 #ifdef CONFIG_KALLSYMS
469 	/* Protected by RCU and/or module_mutex: use rcu_dereference() */
470 	struct mod_kallsyms __rcu *kallsyms;
471 	struct mod_kallsyms core_kallsyms;
472 
473 	/* Section attributes */
474 	struct module_sect_attrs *sect_attrs;
475 
476 	/* Notes attributes */
477 	struct module_notes_attrs *notes_attrs;
478 #endif
479 
480 	/* The command line arguments (may be mangled).  People like
481 	   keeping pointers to this stuff */
482 	char *args;
483 
484 #ifdef CONFIG_SMP
485 	/* Per-cpu data. */
486 	void __percpu *percpu;
487 	unsigned int percpu_size;
488 #endif
489 	void *noinstr_text_start;
490 	unsigned int noinstr_text_size;
491 
492 #ifdef CONFIG_TRACEPOINTS
493 	unsigned int num_tracepoints;
494 	tracepoint_ptr_t *tracepoints_ptrs;
495 #endif
496 #ifdef CONFIG_TREE_SRCU
497 	unsigned int num_srcu_structs;
498 	struct srcu_struct **srcu_struct_ptrs;
499 #endif
500 #ifdef CONFIG_BPF_EVENTS
501 	unsigned int num_bpf_raw_events;
502 	struct bpf_raw_event_map *bpf_raw_events;
503 #endif
504 #ifdef CONFIG_DEBUG_INFO_BTF_MODULES
505 	unsigned int btf_data_size;
506 	unsigned int btf_base_data_size;
507 	void *btf_data;
508 	void *btf_base_data;
509 #endif
510 #ifdef CONFIG_JUMP_LABEL
511 	struct jump_entry *jump_entries;
512 	unsigned int num_jump_entries;
513 #endif
514 #ifdef CONFIG_TRACING
515 	unsigned int num_trace_bprintk_fmt;
516 	const char **trace_bprintk_fmt_start;
517 #endif
518 #ifdef CONFIG_EVENT_TRACING
519 	struct trace_event_call **trace_events;
520 	unsigned int num_trace_events;
521 	struct trace_eval_map **trace_evals;
522 	unsigned int num_trace_evals;
523 #endif
524 #ifdef CONFIG_DYNAMIC_FTRACE
525 	unsigned int num_ftrace_callsites;
526 	unsigned long *ftrace_callsites;
527 #endif
528 #ifdef CONFIG_KPROBES
529 	void *kprobes_text_start;
530 	unsigned int kprobes_text_size;
531 	unsigned long *kprobe_blacklist;
532 	unsigned int num_kprobe_blacklist;
533 #endif
534 #ifdef CONFIG_HAVE_STATIC_CALL_INLINE
535 	int num_static_call_sites;
536 	struct static_call_site *static_call_sites;
537 #endif
538 #if IS_ENABLED(CONFIG_KUNIT)
539 	int num_kunit_init_suites;
540 	struct kunit_suite **kunit_init_suites;
541 	int num_kunit_suites;
542 	struct kunit_suite **kunit_suites;
543 #endif
544 
545 
546 #ifdef CONFIG_LIVEPATCH
547 	bool klp; /* Is this a livepatch module? */
548 	bool klp_alive;
549 
550 	/* ELF information */
551 	struct klp_modinfo *klp_info;
552 #endif
553 
554 #ifdef CONFIG_PRINTK_INDEX
555 	unsigned int printk_index_size;
556 	struct pi_entry **printk_index_start;
557 #endif
558 
559 #ifdef CONFIG_MODULE_UNLOAD
560 	/* What modules depend on me? */
561 	struct list_head source_list;
562 	/* What modules do I depend on? */
563 	struct list_head target_list;
564 
565 	/* Destruction function. */
566 	void (*exit)(void);
567 
568 	atomic_t refcnt;
569 #endif
570 
571 #ifdef CONFIG_CONSTRUCTORS
572 	/* Constructor functions. */
573 	ctor_fn_t *ctors;
574 	unsigned int num_ctors;
575 #endif
576 
577 #ifdef CONFIG_FUNCTION_ERROR_INJECTION
578 	struct error_injection_entry *ei_funcs;
579 	unsigned int num_ei_funcs;
580 #endif
581 #ifdef CONFIG_DYNAMIC_DEBUG_CORE
582 	struct _ddebug_info dyndbg_info;
583 #endif
584 } ____cacheline_aligned __randomize_layout;
585 #ifndef MODULE_ARCH_INIT
586 #define MODULE_ARCH_INIT {}
587 #endif
588 
589 #ifdef CONFIG_MODULES
590 
591 /* Get/put a kernel symbol (calls must be symmetric) */
592 void *__symbol_get(const char *symbol);
593 void *__symbol_get_gpl(const char *symbol);
594 #define symbol_get(x)	({ \
595 	static const char __notrim[] \
596 		__used __section(".no_trim_symbol") = __stringify(x); \
597 	(typeof(&x))(__symbol_get(__stringify(x))); })
598 
599 #ifndef HAVE_ARCH_KALLSYMS_SYMBOL_VALUE
kallsyms_symbol_value(const Elf_Sym * sym)600 static inline unsigned long kallsyms_symbol_value(const Elf_Sym *sym)
601 {
602 	return sym->st_value;
603 }
604 #endif
605 
606 /* FIXME: It'd be nice to isolate modules during init, too, so they
607    aren't used before they (may) fail.  But presently too much code
608    (IDE & SCSI) require entry into the module during init.*/
module_is_live(struct module * mod)609 static inline bool module_is_live(struct module *mod)
610 {
611 	return mod->state != MODULE_STATE_GOING;
612 }
613 
module_is_coming(struct module * mod)614 static inline bool module_is_coming(struct module *mod)
615 {
616         return mod->state == MODULE_STATE_COMING;
617 }
618 
619 struct module *__module_text_address(unsigned long addr);
620 struct module *__module_address(unsigned long addr);
621 bool is_module_address(unsigned long addr);
622 bool __is_module_percpu_address(unsigned long addr, unsigned long *can_addr);
623 bool is_module_percpu_address(unsigned long addr);
624 bool is_module_text_address(unsigned long addr);
625 
within_module_mem_type(unsigned long addr,const struct module * mod,enum mod_mem_type type)626 static inline bool within_module_mem_type(unsigned long addr,
627 					  const struct module *mod,
628 					  enum mod_mem_type type)
629 {
630 	unsigned long base, size;
631 
632 	base = (unsigned long)mod->mem[type].base;
633 	size = mod->mem[type].size;
634 	return addr - base < size;
635 }
636 
within_module_core(unsigned long addr,const struct module * mod)637 static inline bool within_module_core(unsigned long addr,
638 				      const struct module *mod)
639 {
640 	for_class_mod_mem_type(type, core) {
641 		if (within_module_mem_type(addr, mod, type))
642 			return true;
643 	}
644 	return false;
645 }
646 
within_module_init(unsigned long addr,const struct module * mod)647 static inline bool within_module_init(unsigned long addr,
648 				      const struct module *mod)
649 {
650 	for_class_mod_mem_type(type, init) {
651 		if (within_module_mem_type(addr, mod, type))
652 			return true;
653 	}
654 	return false;
655 }
656 
within_module(unsigned long addr,const struct module * mod)657 static inline bool within_module(unsigned long addr, const struct module *mod)
658 {
659 	return within_module_init(addr, mod) || within_module_core(addr, mod);
660 }
661 
662 /* Search for module by name: must be in a RCU critical section. */
663 struct module *find_module(const char *name);
664 
665 extern void __noreturn __module_put_and_kthread_exit(struct module *mod,
666 			long code);
667 #define module_put_and_kthread_exit(code) __module_put_and_kthread_exit(THIS_MODULE, code)
668 
669 #ifdef CONFIG_MODULE_UNLOAD
670 int module_refcount(struct module *mod);
671 void __symbol_put(const char *symbol);
672 #define symbol_put(x) __symbol_put(__stringify(x))
673 void symbol_put_addr(void *addr);
674 
675 /* Sometimes we know we already have a refcount, and it's easier not
676    to handle the error case (which only happens with rmmod --wait). */
677 extern void __module_get(struct module *module);
678 
679 /**
680  * try_module_get() - take module refcount unless module is being removed
681  * @module: the module we should check for
682  *
683  * Only try to get a module reference count if the module is not being removed.
684  * This call will fail if the module is in the process of being removed.
685  *
686  * Care must also be taken to ensure the module exists and is alive prior to
687  * usage of this call. This can be gauranteed through two means:
688  *
689  * 1) Direct protection: you know an earlier caller must have increased the
690  *    module reference through __module_get(). This can typically be achieved
691  *    by having another entity other than the module itself increment the
692  *    module reference count.
693  *
694  * 2) Implied protection: there is an implied protection against module
695  *    removal. An example of this is the implied protection used by kernfs /
696  *    sysfs. The sysfs store / read file operations are guaranteed to exist
697  *    through the use of kernfs's active reference (see kernfs_active()) and a
698  *    sysfs / kernfs file removal cannot happen unless the same file is not
699  *    active. Therefore, if a sysfs file is being read or written to the module
700  *    which created it must still exist. It is therefore safe to use
701  *    try_module_get() on module sysfs store / read ops.
702  *
703  * One of the real values to try_module_get() is the module_is_live() check
704  * which ensures that the caller of try_module_get() can yield to userspace
705  * module removal requests and gracefully fail if the module is on its way out.
706  *
707  * Returns true if the reference count was successfully incremented.
708  */
709 extern bool try_module_get(struct module *module);
710 
711 /**
712  * module_put() - release a reference count to a module
713  * @module: the module we should release a reference count for
714  *
715  * If you successfully bump a reference count to a module with try_module_get(),
716  * when you are finished you must call module_put() to release that reference
717  * count.
718  */
719 extern void module_put(struct module *module);
720 
721 #else /*!CONFIG_MODULE_UNLOAD*/
try_module_get(struct module * module)722 static inline bool try_module_get(struct module *module)
723 {
724 	return !module || module_is_live(module);
725 }
module_put(struct module * module)726 static inline void module_put(struct module *module)
727 {
728 }
__module_get(struct module * module)729 static inline void __module_get(struct module *module)
730 {
731 }
732 #define symbol_put(x) do { } while (0)
733 #define symbol_put_addr(p) do { } while (0)
734 
735 #endif /* CONFIG_MODULE_UNLOAD */
736 
737 /* This is a #define so the string doesn't get put in every .o file */
738 #define module_name(mod)			\
739 ({						\
740 	struct module *__mod = (mod);		\
741 	__mod ? __mod->name : "kernel";		\
742 })
743 
module_buildid(struct module * mod)744 static inline const unsigned char *module_buildid(struct module *mod)
745 {
746 #ifdef CONFIG_STACKTRACE_BUILD_ID
747 	return mod->build_id;
748 #else
749 	return NULL;
750 #endif
751 }
752 
753 /* Dereference module function descriptor */
754 void *dereference_module_function_descriptor(struct module *mod, void *ptr);
755 
756 int register_module_notifier(struct notifier_block *nb);
757 int unregister_module_notifier(struct notifier_block *nb);
758 
759 extern void print_modules(void);
760 
module_requested_async_probing(struct module * module)761 static inline bool module_requested_async_probing(struct module *module)
762 {
763 	return module && module->async_probe_requested;
764 }
765 
is_livepatch_module(struct module * mod)766 static inline bool is_livepatch_module(struct module *mod)
767 {
768 #ifdef CONFIG_LIVEPATCH
769 	return mod->klp;
770 #else
771 	return false;
772 #endif
773 }
774 
775 void module_for_each_mod(int(*func)(struct module *mod, void *data), void *data);
776 
777 #else /* !CONFIG_MODULES... */
778 
__module_address(unsigned long addr)779 static inline struct module *__module_address(unsigned long addr)
780 {
781 	return NULL;
782 }
783 
__module_text_address(unsigned long addr)784 static inline struct module *__module_text_address(unsigned long addr)
785 {
786 	return NULL;
787 }
788 
is_module_address(unsigned long addr)789 static inline bool is_module_address(unsigned long addr)
790 {
791 	return false;
792 }
793 
is_module_percpu_address(unsigned long addr)794 static inline bool is_module_percpu_address(unsigned long addr)
795 {
796 	return false;
797 }
798 
__is_module_percpu_address(unsigned long addr,unsigned long * can_addr)799 static inline bool __is_module_percpu_address(unsigned long addr, unsigned long *can_addr)
800 {
801 	return false;
802 }
803 
is_module_text_address(unsigned long addr)804 static inline bool is_module_text_address(unsigned long addr)
805 {
806 	return false;
807 }
808 
within_module_core(unsigned long addr,const struct module * mod)809 static inline bool within_module_core(unsigned long addr,
810 				      const struct module *mod)
811 {
812 	return false;
813 }
814 
within_module_init(unsigned long addr,const struct module * mod)815 static inline bool within_module_init(unsigned long addr,
816 				      const struct module *mod)
817 {
818 	return false;
819 }
820 
within_module(unsigned long addr,const struct module * mod)821 static inline bool within_module(unsigned long addr, const struct module *mod)
822 {
823 	return false;
824 }
825 
826 /* Get/put a kernel symbol (calls should be symmetric) */
827 #define symbol_get(x) ({ extern typeof(x) x __attribute__((weak,visibility("hidden"))); &(x); })
828 #define symbol_put(x) do { } while (0)
829 #define symbol_put_addr(x) do { } while (0)
830 
__module_get(struct module * module)831 static inline void __module_get(struct module *module)
832 {
833 }
834 
try_module_get(struct module * module)835 static inline bool try_module_get(struct module *module)
836 {
837 	return true;
838 }
839 
module_put(struct module * module)840 static inline void module_put(struct module *module)
841 {
842 }
843 
844 #define module_name(mod) "kernel"
845 
register_module_notifier(struct notifier_block * nb)846 static inline int register_module_notifier(struct notifier_block *nb)
847 {
848 	/* no events will happen anyway, so this can always succeed */
849 	return 0;
850 }
851 
unregister_module_notifier(struct notifier_block * nb)852 static inline int unregister_module_notifier(struct notifier_block *nb)
853 {
854 	return 0;
855 }
856 
857 #define module_put_and_kthread_exit(code) kthread_exit(code)
858 
print_modules(void)859 static inline void print_modules(void)
860 {
861 }
862 
module_requested_async_probing(struct module * module)863 static inline bool module_requested_async_probing(struct module *module)
864 {
865 	return false;
866 }
867 
868 
869 /* Dereference module function descriptor */
870 static inline
dereference_module_function_descriptor(struct module * mod,void * ptr)871 void *dereference_module_function_descriptor(struct module *mod, void *ptr)
872 {
873 	return ptr;
874 }
875 
module_is_coming(struct module * mod)876 static inline bool module_is_coming(struct module *mod)
877 {
878 	return false;
879 }
880 
module_for_each_mod(int (* func)(struct module * mod,void * data),void * data)881 static inline void module_for_each_mod(int(*func)(struct module *mod, void *data), void *data)
882 {
883 }
884 #endif /* CONFIG_MODULES */
885 
886 #ifdef CONFIG_SYSFS
887 extern struct kset *module_kset;
888 extern const struct kobj_type module_ktype;
889 #endif /* CONFIG_SYSFS */
890 
891 #define symbol_request(x) try_then_request_module(symbol_get(x), "symbol:" #x)
892 
893 /* BELOW HERE ALL THESE ARE OBSOLETE AND WILL VANISH */
894 
895 #define __MODULE_STRING(x) __stringify(x)
896 
897 #ifdef CONFIG_GENERIC_BUG
898 void module_bug_finalize(const Elf_Ehdr *, const Elf_Shdr *,
899 			 struct module *);
900 void module_bug_cleanup(struct module *);
901 
902 #else	/* !CONFIG_GENERIC_BUG */
903 
module_bug_finalize(const Elf_Ehdr * hdr,const Elf_Shdr * sechdrs,struct module * mod)904 static inline void module_bug_finalize(const Elf_Ehdr *hdr,
905 					const Elf_Shdr *sechdrs,
906 					struct module *mod)
907 {
908 }
module_bug_cleanup(struct module * mod)909 static inline void module_bug_cleanup(struct module *mod) {}
910 #endif	/* CONFIG_GENERIC_BUG */
911 
912 #ifdef CONFIG_MITIGATION_RETPOLINE
913 extern bool retpoline_module_ok(bool has_retpoline);
914 #else
retpoline_module_ok(bool has_retpoline)915 static inline bool retpoline_module_ok(bool has_retpoline)
916 {
917 	return true;
918 }
919 #endif
920 
921 #ifdef CONFIG_MODULE_SIG
922 bool is_module_sig_enforced(void);
923 
924 void set_module_sig_enforced(void);
925 
module_sig_ok(struct module * module)926 static inline bool module_sig_ok(struct module *module)
927 {
928 	return module->sig_ok;
929 }
930 #else	/* !CONFIG_MODULE_SIG */
is_module_sig_enforced(void)931 static inline bool is_module_sig_enforced(void)
932 {
933 	return false;
934 }
935 
set_module_sig_enforced(void)936 static inline void set_module_sig_enforced(void)
937 {
938 }
939 
module_sig_ok(struct module * module)940 static inline bool module_sig_ok(struct module *module)
941 {
942 	return true;
943 }
944 #endif	/* CONFIG_MODULE_SIG */
945 
946 #if defined(CONFIG_MODULES) && defined(CONFIG_KALLSYMS)
947 int module_kallsyms_on_each_symbol(const char *modname,
948 				   int (*fn)(void *, const char *, unsigned long),
949 				   void *data);
950 
951 /* For kallsyms to ask for address resolution.  namebuf should be at
952  * least KSYM_NAME_LEN long: a pointer to namebuf is returned if
953  * found, otherwise NULL.
954  */
955 int module_address_lookup(unsigned long addr,
956 			  unsigned long *symbolsize,
957 			  unsigned long *offset,
958 			  char **modname, const unsigned char **modbuildid,
959 			  char *namebuf);
960 int lookup_module_symbol_name(unsigned long addr, char *symname);
961 int lookup_module_symbol_attrs(unsigned long addr,
962 			       unsigned long *size,
963 			       unsigned long *offset,
964 			       char *modname,
965 			       char *name);
966 
967 /* Returns 0 and fills in value, defined and namebuf, or -ERANGE if
968  * symnum out of range.
969  */
970 int module_get_kallsym(unsigned int symnum, unsigned long *value, char *type,
971 		       char *name, char *module_name, int *exported);
972 
973 /* Look for this name: can be of form module:name. */
974 unsigned long module_kallsyms_lookup_name(const char *name);
975 
976 unsigned long find_kallsyms_symbol_value(struct module *mod, const char *name);
977 
978 #else	/* CONFIG_MODULES && CONFIG_KALLSYMS */
979 
module_kallsyms_on_each_symbol(const char * modname,int (* fn)(void *,const char *,unsigned long),void * data)980 static inline int module_kallsyms_on_each_symbol(const char *modname,
981 						 int (*fn)(void *, const char *, unsigned long),
982 						 void *data)
983 {
984 	return -EOPNOTSUPP;
985 }
986 
987 /* For kallsyms to ask for address resolution.  NULL means not found. */
module_address_lookup(unsigned long addr,unsigned long * symbolsize,unsigned long * offset,char ** modname,const unsigned char ** modbuildid,char * namebuf)988 static inline int module_address_lookup(unsigned long addr,
989 						unsigned long *symbolsize,
990 						unsigned long *offset,
991 						char **modname,
992 						const unsigned char **modbuildid,
993 						char *namebuf)
994 {
995 	return 0;
996 }
997 
lookup_module_symbol_name(unsigned long addr,char * symname)998 static inline int lookup_module_symbol_name(unsigned long addr, char *symname)
999 {
1000 	return -ERANGE;
1001 }
1002 
module_get_kallsym(unsigned int symnum,unsigned long * value,char * type,char * name,char * module_name,int * exported)1003 static inline int module_get_kallsym(unsigned int symnum, unsigned long *value,
1004 				     char *type, char *name,
1005 				     char *module_name, int *exported)
1006 {
1007 	return -ERANGE;
1008 }
1009 
module_kallsyms_lookup_name(const char * name)1010 static inline unsigned long module_kallsyms_lookup_name(const char *name)
1011 {
1012 	return 0;
1013 }
1014 
find_kallsyms_symbol_value(struct module * mod,const char * name)1015 static inline unsigned long find_kallsyms_symbol_value(struct module *mod,
1016 						       const char *name)
1017 {
1018 	return 0;
1019 }
1020 
1021 #endif  /* CONFIG_MODULES && CONFIG_KALLSYMS */
1022 
1023 /* Define __free(module_put) macro for struct module *. */
1024 DEFINE_FREE(module_put, struct module *, if (_T) module_put(_T))
1025 
1026 #endif /* _LINUX_MODULE_H */
1027