xref: /linux-6.15/include/linux/module.h (revision c287c072)
1 /* SPDX-License-Identifier: GPL-2.0-only */
2 /*
3  * Dynamic loading of modules into the kernel.
4  *
5  * Rewritten by Richard Henderson <[email protected]> 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/kmod.h>
18 #include <linux/init.h>
19 #include <linux/elf.h>
20 #include <linux/stringify.h>
21 #include <linux/kobject.h>
22 #include <linux/moduleparam.h>
23 #include <linux/jump_label.h>
24 #include <linux/export.h>
25 #include <linux/rbtree_latch.h>
26 #include <linux/error-injection.h>
27 #include <linux/tracepoint-defs.h>
28 #include <linux/srcu.h>
29 #include <linux/static_call_types.h>
30 #include <linux/dynamic_debug.h>
31 
32 #include <linux/percpu.h>
33 #include <asm/module.h>
34 
35 #define MODULE_NAME_LEN MAX_PARAM_PREFIX_LEN
36 
37 struct modversion_info {
38 	unsigned long crc;
39 	char name[MODULE_NAME_LEN];
40 };
41 
42 struct module;
43 struct exception_table_entry;
44 
45 struct module_kobject {
46 	struct kobject kobj;
47 	struct module *mod;
48 	struct kobject *drivers_dir;
49 	struct module_param_attrs *mp;
50 	struct completion *kobj_completion;
51 } __randomize_layout;
52 
53 struct module_attribute {
54 	struct attribute attr;
55 	ssize_t (*show)(const struct module_attribute *, struct module_kobject *,
56 			char *);
57 	ssize_t (*store)(const struct module_attribute *, struct module_kobject *,
58 			 const char *, size_t count);
59 	void (*setup)(struct module *, const char *);
60 	int (*test)(struct module *);
61 	void (*free)(struct module *);
62 };
63 
64 struct module_version_attribute {
65 	struct module_attribute mattr;
66 	const char *module_name;
67 	const char *version;
68 };
69 
70 extern ssize_t __modver_version_show(const struct module_attribute *,
71 				     struct module_kobject *, char *);
72 
73 extern const struct module_attribute module_uevent;
74 
75 /* These are either module local, or the kernel's dummy ones. */
76 extern int init_module(void);
77 extern void cleanup_module(void);
78 
79 #ifndef MODULE
80 /**
81  * module_init() - driver initialization entry point
82  * @x: function to be run at kernel boot time or module insertion
83  *
84  * module_init() will either be called during do_initcalls() (if
85  * builtin) or at module insertion time (if a module).  There can only
86  * be one per module.
87  */
88 #define module_init(x)	__initcall(x);
89 
90 /**
91  * module_exit() - driver exit entry point
92  * @x: function to be run when driver is removed
93  *
94  * module_exit() will wrap the driver clean-up code
95  * with cleanup_module() when used with rmmod when
96  * the driver is a module.  If the driver is statically
97  * compiled into the kernel, module_exit() has no effect.
98  * There can only be one per module.
99  */
100 #define module_exit(x)	__exitcall(x);
101 
102 #else /* MODULE */
103 
104 /*
105  * In most cases loadable modules do not need custom
106  * initcall levels. There are still some valid cases where
107  * a driver may be needed early if built in, and does not
108  * matter when built as a loadable module. Like bus
109  * snooping debug drivers.
110  */
111 #define early_initcall(fn)		module_init(fn)
112 #define core_initcall(fn)		module_init(fn)
113 #define core_initcall_sync(fn)		module_init(fn)
114 #define postcore_initcall(fn)		module_init(fn)
115 #define postcore_initcall_sync(fn)	module_init(fn)
116 #define arch_initcall(fn)		module_init(fn)
117 #define subsys_initcall(fn)		module_init(fn)
118 #define subsys_initcall_sync(fn)	module_init(fn)
119 #define fs_initcall(fn)			module_init(fn)
120 #define fs_initcall_sync(fn)		module_init(fn)
121 #define rootfs_initcall(fn)		module_init(fn)
122 #define device_initcall(fn)		module_init(fn)
123 #define device_initcall_sync(fn)	module_init(fn)
124 #define late_initcall(fn)		module_init(fn)
125 #define late_initcall_sync(fn)		module_init(fn)
126 
127 #define console_initcall(fn)		module_init(fn)
128 
129 /* Each module must use one module_init(). */
130 #define module_init(initfn)					\
131 	static inline initcall_t __maybe_unused __inittest(void)		\
132 	{ return initfn; }					\
133 	int init_module(void) __copy(initfn)			\
134 		__attribute__((alias(#initfn)));		\
135 	___ADDRESSABLE(init_module, __initdata);
136 
137 /* This is only required if you want to be unloadable. */
138 #define module_exit(exitfn)					\
139 	static inline exitcall_t __maybe_unused __exittest(void)		\
140 	{ return exitfn; }					\
141 	void cleanup_module(void) __copy(exitfn)		\
142 		__attribute__((alias(#exitfn)));		\
143 	___ADDRESSABLE(cleanup_module, __exitdata);
144 
145 #endif
146 
147 /* This means "can be init if no module support, otherwise module load
148    may call it." */
149 #ifdef CONFIG_MODULES
150 #define __init_or_module
151 #define __initdata_or_module
152 #define __initconst_or_module
153 #define __INIT_OR_MODULE	.text
154 #define __INITDATA_OR_MODULE	.data
155 #define __INITRODATA_OR_MODULE	.section ".rodata","a",%progbits
156 #else
157 #define __init_or_module __init
158 #define __initdata_or_module __initdata
159 #define __initconst_or_module __initconst
160 #define __INIT_OR_MODULE __INIT
161 #define __INITDATA_OR_MODULE __INITDATA
162 #define __INITRODATA_OR_MODULE __INITRODATA
163 #endif /*CONFIG_MODULES*/
164 
165 /* Generic info of form tag = "info" */
166 #define MODULE_INFO(tag, info) __MODULE_INFO(tag, tag, info)
167 
168 /* For userspace: you can also call me... */
169 #define MODULE_ALIAS(_alias) MODULE_INFO(alias, _alias)
170 
171 /* Soft module dependencies. See man modprobe.d for details.
172  * Example: MODULE_SOFTDEP("pre: module-foo module-bar post: module-baz")
173  */
174 #define MODULE_SOFTDEP(_softdep) MODULE_INFO(softdep, _softdep)
175 
176 /*
177  * Weak module dependencies. See man modprobe.d for details.
178  * Example: MODULE_WEAKDEP("module-foo")
179  */
180 #define MODULE_WEAKDEP(_weakdep) MODULE_INFO(weakdep, _weakdep)
181 
182 /*
183  * MODULE_FILE is used for generating modules.builtin
184  * So, make it no-op when this is being built as a module
185  */
186 #ifdef MODULE
187 #define MODULE_FILE
188 #else
189 #define MODULE_FILE	MODULE_INFO(file, KBUILD_MODFILE);
190 #endif
191 
192 /*
193  * The following license idents are currently accepted as indicating free
194  * software modules
195  *
196  *	"GPL"				[GNU Public License v2]
197  *	"GPL v2"			[GNU Public License v2]
198  *	"GPL and additional rights"	[GNU Public License v2 rights and more]
199  *	"Dual BSD/GPL"			[GNU Public License v2
200  *					 or BSD license choice]
201  *	"Dual MIT/GPL"			[GNU Public License v2
202  *					 or MIT license choice]
203  *	"Dual MPL/GPL"			[GNU Public License v2
204  *					 or Mozilla license choice]
205  *
206  * The following other idents are available
207  *
208  *	"Proprietary"			[Non free products]
209  *
210  * Both "GPL v2" and "GPL" (the latter also in dual licensed strings) are
211  * merely stating that the module is licensed under the GPL v2, but are not
212  * telling whether "GPL v2 only" or "GPL v2 or later". The reason why there
213  * are two variants is a historic and failed attempt to convey more
214  * information in the MODULE_LICENSE string. For module loading the
215  * "only/or later" distinction is completely irrelevant and does neither
216  * replace the proper license identifiers in the corresponding source file
217  * nor amends them in any way. The sole purpose is to make the
218  * 'Proprietary' flagging work and to refuse to bind symbols which are
219  * exported with EXPORT_SYMBOL_GPL when a non free module is loaded.
220  *
221  * In the same way "BSD" is not a clear license information. It merely
222  * states, that the module is licensed under one of the compatible BSD
223  * license variants. The detailed and correct license information is again
224  * to be found in the corresponding source files.
225  *
226  * There are dual licensed components, but when running with Linux it is the
227  * GPL that is relevant so this is a non issue. Similarly LGPL linked with GPL
228  * is a GPL combined work.
229  *
230  * This exists for several reasons
231  * 1.	So modinfo can show license info for users wanting to vet their setup
232  *	is free
233  * 2.	So the community can ignore bug reports including proprietary modules
234  * 3.	So vendors can do likewise based on their own policies
235  */
236 #define MODULE_LICENSE(_license) MODULE_FILE MODULE_INFO(license, _license)
237 
238 /*
239  * Author(s), use "Name <email>" or just "Name", for multiple
240  * authors use multiple MODULE_AUTHOR() statements/lines.
241  */
242 #define MODULE_AUTHOR(_author) MODULE_INFO(author, _author)
243 
244 /* What your module does. */
245 #define MODULE_DESCRIPTION(_description) MODULE_INFO(description, _description)
246 
247 #ifdef MODULE
248 /* Creates an alias so file2alias.c can find device table. */
249 #define MODULE_DEVICE_TABLE(type, name)					\
250 extern typeof(name) __mod_device_table__##type##__##name		\
251   __attribute__ ((unused, alias(__stringify(name))))
252 #else  /* !MODULE */
253 #define MODULE_DEVICE_TABLE(type, name)
254 #endif
255 
256 /* Version of form [<epoch>:]<version>[-<extra-version>].
257  * Or for CVS/RCS ID version, everything but the number is stripped.
258  * <epoch>: A (small) unsigned integer which allows you to start versions
259  * anew. If not mentioned, it's zero.  eg. "2:1.0" is after
260  * "1:2.0".
261 
262  * <version>: The <version> may contain only alphanumerics and the
263  * character `.'.  Ordered by numeric sort for numeric parts,
264  * ascii sort for ascii parts (as per RPM or DEB algorithm).
265 
266  * <extraversion>: Like <version>, but inserted for local
267  * customizations, eg "rh3" or "rusty1".
268 
269  * Using this automatically adds a checksum of the .c files and the
270  * local headers in "srcversion".
271  */
272 
273 #if defined(MODULE) || !defined(CONFIG_SYSFS)
274 #define MODULE_VERSION(_version) MODULE_INFO(version, _version)
275 #else
276 #define MODULE_VERSION(_version)					\
277 	MODULE_INFO(version, _version);					\
278 	static const struct module_version_attribute __modver_attr	\
279 		__used __section("__modver")				\
280 		__aligned(__alignof__(struct module_version_attribute)) \
281 		= {							\
282 			.mattr	= {					\
283 				.attr	= {				\
284 					.name	= "version",		\
285 					.mode	= S_IRUGO,		\
286 				},					\
287 				.show	= __modver_version_show,	\
288 			},						\
289 			.module_name	= KBUILD_MODNAME,		\
290 			.version	= _version,			\
291 		}
292 #endif
293 
294 /* Optional firmware file (or files) needed by the module
295  * format is simply firmware file name.  Multiple firmware
296  * files require multiple MODULE_FIRMWARE() specifiers */
297 #define MODULE_FIRMWARE(_firmware) MODULE_INFO(firmware, _firmware)
298 
299 #define MODULE_IMPORT_NS(ns)	MODULE_INFO(import_ns, ns)
300 
301 struct notifier_block;
302 
303 #ifdef CONFIG_MODULES
304 
305 extern int modules_disabled; /* for sysctl */
306 /* Get/put a kernel symbol (calls must be symmetric) */
307 void *__symbol_get(const char *symbol);
308 void *__symbol_get_gpl(const char *symbol);
309 #define symbol_get(x) ((typeof(&x))(__symbol_get(__stringify(x))))
310 
311 /* modules using other modules: kdb wants to see this. */
312 struct module_use {
313 	struct list_head source_list;
314 	struct list_head target_list;
315 	struct module *source, *target;
316 };
317 
318 enum module_state {
319 	MODULE_STATE_LIVE,	/* Normal state. */
320 	MODULE_STATE_COMING,	/* Full formed, running module_init. */
321 	MODULE_STATE_GOING,	/* Going away. */
322 	MODULE_STATE_UNFORMED,	/* Still setting it up. */
323 };
324 
325 struct mod_tree_node {
326 	struct module *mod;
327 	struct latch_tree_node node;
328 };
329 
330 enum mod_mem_type {
331 	MOD_TEXT = 0,
332 	MOD_DATA,
333 	MOD_RODATA,
334 	MOD_RO_AFTER_INIT,
335 	MOD_INIT_TEXT,
336 	MOD_INIT_DATA,
337 	MOD_INIT_RODATA,
338 
339 	MOD_MEM_NUM_TYPES,
340 	MOD_INVALID = -1,
341 };
342 
343 #define mod_mem_type_is_init(type)	\
344 	((type) == MOD_INIT_TEXT ||	\
345 	 (type) == MOD_INIT_DATA ||	\
346 	 (type) == MOD_INIT_RODATA)
347 
348 #define mod_mem_type_is_core(type) (!mod_mem_type_is_init(type))
349 
350 #define mod_mem_type_is_text(type)	\
351 	 ((type) == MOD_TEXT ||		\
352 	  (type) == MOD_INIT_TEXT)
353 
354 #define mod_mem_type_is_data(type) (!mod_mem_type_is_text(type))
355 
356 #define mod_mem_type_is_core_data(type)	\
357 	(mod_mem_type_is_core(type) &&	\
358 	 mod_mem_type_is_data(type))
359 
360 #define for_each_mod_mem_type(type)			\
361 	for (enum mod_mem_type (type) = 0;		\
362 	     (type) < MOD_MEM_NUM_TYPES; (type)++)
363 
364 #define for_class_mod_mem_type(type, class)		\
365 	for_each_mod_mem_type(type)			\
366 		if (mod_mem_type_is_##class(type))
367 
368 struct module_memory {
369 	void *base;
370 	bool is_rox;
371 	unsigned int size;
372 
373 #ifdef CONFIG_MODULES_TREE_LOOKUP
374 	struct mod_tree_node mtn;
375 #endif
376 };
377 
378 #ifdef CONFIG_MODULES_TREE_LOOKUP
379 /* Only touch one cacheline for common rbtree-for-core-layout case. */
380 #define __module_memory_align ____cacheline_aligned
381 #else
382 #define __module_memory_align
383 #endif
384 
385 struct mod_kallsyms {
386 	Elf_Sym *symtab;
387 	unsigned int num_symtab;
388 	char *strtab;
389 	char *typetab;
390 };
391 
392 #ifdef CONFIG_LIVEPATCH
393 /**
394  * struct klp_modinfo - ELF information preserved from the livepatch module
395  *
396  * @hdr: ELF header
397  * @sechdrs: Section header table
398  * @secstrings: String table for the section headers
399  * @symndx: The symbol table section index
400  */
401 struct klp_modinfo {
402 	Elf_Ehdr hdr;
403 	Elf_Shdr *sechdrs;
404 	char *secstrings;
405 	unsigned int symndx;
406 };
407 #endif
408 
409 struct module {
410 	enum module_state state;
411 
412 	/* Member of list of modules */
413 	struct list_head list;
414 
415 	/* Unique handle for this module */
416 	char name[MODULE_NAME_LEN];
417 
418 #ifdef CONFIG_STACKTRACE_BUILD_ID
419 	/* Module build ID */
420 	unsigned char build_id[BUILD_ID_SIZE_MAX];
421 #endif
422 
423 	/* Sysfs stuff. */
424 	struct module_kobject mkobj;
425 	struct module_attribute *modinfo_attrs;
426 	const char *version;
427 	const char *srcversion;
428 	struct kobject *holders_dir;
429 
430 	/* Exported symbols */
431 	const struct kernel_symbol *syms;
432 	const u32 *crcs;
433 	unsigned int num_syms;
434 
435 #ifdef CONFIG_ARCH_USES_CFI_TRAPS
436 	s32 *kcfi_traps;
437 	s32 *kcfi_traps_end;
438 #endif
439 
440 	/* Kernel parameters. */
441 #ifdef CONFIG_SYSFS
442 	struct mutex param_lock;
443 #endif
444 	struct kernel_param *kp;
445 	unsigned int num_kp;
446 
447 	/* GPL-only exported symbols. */
448 	unsigned int num_gpl_syms;
449 	const struct kernel_symbol *gpl_syms;
450 	const u32 *gpl_crcs;
451 	bool using_gplonly_symbols;
452 
453 #ifdef CONFIG_MODULE_SIG
454 	/* Signature was verified. */
455 	bool sig_ok;
456 #endif
457 
458 	bool async_probe_requested;
459 
460 	/* Exception table */
461 	unsigned int num_exentries;
462 	struct exception_table_entry *extable;
463 
464 	/* Startup function. */
465 	int (*init)(void);
466 
467 	struct module_memory mem[MOD_MEM_NUM_TYPES] __module_memory_align;
468 
469 	/* Arch-specific module values */
470 	struct mod_arch_specific arch;
471 
472 	unsigned long taints;	/* same bits as kernel:taint_flags */
473 
474 #ifdef CONFIG_GENERIC_BUG
475 	/* Support for BUG */
476 	unsigned num_bugs;
477 	struct list_head bug_list;
478 	struct bug_entry *bug_table;
479 #endif
480 
481 #ifdef CONFIG_KALLSYMS
482 	/* Protected by RCU and/or module_mutex: use rcu_dereference() */
483 	struct mod_kallsyms __rcu *kallsyms;
484 	struct mod_kallsyms core_kallsyms;
485 
486 	/* Section attributes */
487 	struct module_sect_attrs *sect_attrs;
488 
489 	/* Notes attributes */
490 	struct module_notes_attrs *notes_attrs;
491 #endif
492 
493 	/* The command line arguments (may be mangled).  People like
494 	   keeping pointers to this stuff */
495 	char *args;
496 
497 #ifdef CONFIG_SMP
498 	/* Per-cpu data. */
499 	void __percpu *percpu;
500 	unsigned int percpu_size;
501 #endif
502 	void *noinstr_text_start;
503 	unsigned int noinstr_text_size;
504 
505 #ifdef CONFIG_TRACEPOINTS
506 	unsigned int num_tracepoints;
507 	tracepoint_ptr_t *tracepoints_ptrs;
508 #endif
509 #ifdef CONFIG_TREE_SRCU
510 	unsigned int num_srcu_structs;
511 	struct srcu_struct **srcu_struct_ptrs;
512 #endif
513 #ifdef CONFIG_BPF_EVENTS
514 	unsigned int num_bpf_raw_events;
515 	struct bpf_raw_event_map *bpf_raw_events;
516 #endif
517 #ifdef CONFIG_DEBUG_INFO_BTF_MODULES
518 	unsigned int btf_data_size;
519 	unsigned int btf_base_data_size;
520 	void *btf_data;
521 	void *btf_base_data;
522 #endif
523 #ifdef CONFIG_JUMP_LABEL
524 	struct jump_entry *jump_entries;
525 	unsigned int num_jump_entries;
526 #endif
527 #ifdef CONFIG_TRACING
528 	unsigned int num_trace_bprintk_fmt;
529 	const char **trace_bprintk_fmt_start;
530 #endif
531 #ifdef CONFIG_EVENT_TRACING
532 	struct trace_event_call **trace_events;
533 	unsigned int num_trace_events;
534 	struct trace_eval_map **trace_evals;
535 	unsigned int num_trace_evals;
536 #endif
537 #ifdef CONFIG_FTRACE_MCOUNT_RECORD
538 	unsigned int num_ftrace_callsites;
539 	unsigned long *ftrace_callsites;
540 #endif
541 #ifdef CONFIG_KPROBES
542 	void *kprobes_text_start;
543 	unsigned int kprobes_text_size;
544 	unsigned long *kprobe_blacklist;
545 	unsigned int num_kprobe_blacklist;
546 #endif
547 #ifdef CONFIG_HAVE_STATIC_CALL_INLINE
548 	int num_static_call_sites;
549 	struct static_call_site *static_call_sites;
550 #endif
551 #if IS_ENABLED(CONFIG_KUNIT)
552 	int num_kunit_init_suites;
553 	struct kunit_suite **kunit_init_suites;
554 	int num_kunit_suites;
555 	struct kunit_suite **kunit_suites;
556 #endif
557 
558 
559 #ifdef CONFIG_LIVEPATCH
560 	bool klp; /* Is this a livepatch module? */
561 	bool klp_alive;
562 
563 	/* ELF information */
564 	struct klp_modinfo *klp_info;
565 #endif
566 
567 #ifdef CONFIG_PRINTK_INDEX
568 	unsigned int printk_index_size;
569 	struct pi_entry **printk_index_start;
570 #endif
571 
572 #ifdef CONFIG_MODULE_UNLOAD
573 	/* What modules depend on me? */
574 	struct list_head source_list;
575 	/* What modules do I depend on? */
576 	struct list_head target_list;
577 
578 	/* Destruction function. */
579 	void (*exit)(void);
580 
581 	atomic_t refcnt;
582 #endif
583 
584 #ifdef CONFIG_CONSTRUCTORS
585 	/* Constructor functions. */
586 	ctor_fn_t *ctors;
587 	unsigned int num_ctors;
588 #endif
589 
590 #ifdef CONFIG_FUNCTION_ERROR_INJECTION
591 	struct error_injection_entry *ei_funcs;
592 	unsigned int num_ei_funcs;
593 #endif
594 #ifdef CONFIG_DYNAMIC_DEBUG_CORE
595 	struct _ddebug_info dyndbg_info;
596 #endif
597 } ____cacheline_aligned __randomize_layout;
598 #ifndef MODULE_ARCH_INIT
599 #define MODULE_ARCH_INIT {}
600 #endif
601 
602 #ifndef HAVE_ARCH_KALLSYMS_SYMBOL_VALUE
603 static inline unsigned long kallsyms_symbol_value(const Elf_Sym *sym)
604 {
605 	return sym->st_value;
606 }
607 #endif
608 
609 /* FIXME: It'd be nice to isolate modules during init, too, so they
610    aren't used before they (may) fail.  But presently too much code
611    (IDE & SCSI) require entry into the module during init.*/
612 static inline bool module_is_live(struct module *mod)
613 {
614 	return mod->state != MODULE_STATE_GOING;
615 }
616 
617 static inline bool module_is_coming(struct module *mod)
618 {
619         return mod->state == MODULE_STATE_COMING;
620 }
621 
622 struct module *__module_text_address(unsigned long addr);
623 struct module *__module_address(unsigned long addr);
624 bool is_module_address(unsigned long addr);
625 bool __is_module_percpu_address(unsigned long addr, unsigned long *can_addr);
626 bool is_module_percpu_address(unsigned long addr);
627 bool is_module_text_address(unsigned long addr);
628 
629 static inline bool within_module_mem_type(unsigned long addr,
630 					  const struct module *mod,
631 					  enum mod_mem_type type)
632 {
633 	unsigned long base, size;
634 
635 	base = (unsigned long)mod->mem[type].base;
636 	size = mod->mem[type].size;
637 	return addr - base < size;
638 }
639 
640 static inline bool within_module_core(unsigned long addr,
641 				      const struct module *mod)
642 {
643 	for_class_mod_mem_type(type, core) {
644 		if (within_module_mem_type(addr, mod, type))
645 			return true;
646 	}
647 	return false;
648 }
649 
650 static inline bool within_module_init(unsigned long addr,
651 				      const struct module *mod)
652 {
653 	for_class_mod_mem_type(type, init) {
654 		if (within_module_mem_type(addr, mod, type))
655 			return true;
656 	}
657 	return false;
658 }
659 
660 static inline bool within_module(unsigned long addr, const struct module *mod)
661 {
662 	return within_module_init(addr, mod) || within_module_core(addr, mod);
663 }
664 
665 /* Search for module by name: must be in a RCU-sched critical section. */
666 struct module *find_module(const char *name);
667 
668 extern void __noreturn __module_put_and_kthread_exit(struct module *mod,
669 			long code);
670 #define module_put_and_kthread_exit(code) __module_put_and_kthread_exit(THIS_MODULE, code)
671 
672 #ifdef CONFIG_MODULE_UNLOAD
673 int module_refcount(struct module *mod);
674 void __symbol_put(const char *symbol);
675 #define symbol_put(x) __symbol_put(__stringify(x))
676 void symbol_put_addr(void *addr);
677 
678 /* Sometimes we know we already have a refcount, and it's easier not
679    to handle the error case (which only happens with rmmod --wait). */
680 extern void __module_get(struct module *module);
681 
682 /**
683  * try_module_get() - take module refcount unless module is being removed
684  * @module: the module we should check for
685  *
686  * Only try to get a module reference count if the module is not being removed.
687  * This call will fail if the module is in the process of being removed.
688  *
689  * Care must also be taken to ensure the module exists and is alive prior to
690  * usage of this call. This can be gauranteed through two means:
691  *
692  * 1) Direct protection: you know an earlier caller must have increased the
693  *    module reference through __module_get(). This can typically be achieved
694  *    by having another entity other than the module itself increment the
695  *    module reference count.
696  *
697  * 2) Implied protection: there is an implied protection against module
698  *    removal. An example of this is the implied protection used by kernfs /
699  *    sysfs. The sysfs store / read file operations are guaranteed to exist
700  *    through the use of kernfs's active reference (see kernfs_active()) and a
701  *    sysfs / kernfs file removal cannot happen unless the same file is not
702  *    active. Therefore, if a sysfs file is being read or written to the module
703  *    which created it must still exist. It is therefore safe to use
704  *    try_module_get() on module sysfs store / read ops.
705  *
706  * One of the real values to try_module_get() is the module_is_live() check
707  * which ensures that the caller of try_module_get() can yield to userspace
708  * module removal requests and gracefully fail if the module is on its way out.
709  *
710  * Returns true if the reference count was successfully incremented.
711  */
712 extern bool try_module_get(struct module *module);
713 
714 /**
715  * module_put() - release a reference count to a module
716  * @module: the module we should release a reference count for
717  *
718  * If you successfully bump a reference count to a module with try_module_get(),
719  * when you are finished you must call module_put() to release that reference
720  * count.
721  */
722 extern void module_put(struct module *module);
723 
724 #else /*!CONFIG_MODULE_UNLOAD*/
725 static inline bool try_module_get(struct module *module)
726 {
727 	return !module || module_is_live(module);
728 }
729 static inline void module_put(struct module *module)
730 {
731 }
732 static inline void __module_get(struct module *module)
733 {
734 }
735 #define symbol_put(x) do { } while (0)
736 #define symbol_put_addr(p) do { } while (0)
737 
738 #endif /* CONFIG_MODULE_UNLOAD */
739 
740 /* This is a #define so the string doesn't get put in every .o file */
741 #define module_name(mod)			\
742 ({						\
743 	struct module *__mod = (mod);		\
744 	__mod ? __mod->name : "kernel";		\
745 })
746 
747 /* Dereference module function descriptor */
748 void *dereference_module_function_descriptor(struct module *mod, void *ptr);
749 
750 int register_module_notifier(struct notifier_block *nb);
751 int unregister_module_notifier(struct notifier_block *nb);
752 
753 extern void print_modules(void);
754 
755 static inline bool module_requested_async_probing(struct module *module)
756 {
757 	return module && module->async_probe_requested;
758 }
759 
760 static inline bool is_livepatch_module(struct module *mod)
761 {
762 #ifdef CONFIG_LIVEPATCH
763 	return mod->klp;
764 #else
765 	return false;
766 #endif
767 }
768 
769 void set_module_sig_enforced(void);
770 
771 static inline void *module_writable_address(struct module *mod, void *loc)
772 {
773 	return loc;
774 }
775 
776 #else /* !CONFIG_MODULES... */
777 
778 static inline struct module *__module_address(unsigned long addr)
779 {
780 	return NULL;
781 }
782 
783 static inline struct module *__module_text_address(unsigned long addr)
784 {
785 	return NULL;
786 }
787 
788 static inline bool is_module_address(unsigned long addr)
789 {
790 	return false;
791 }
792 
793 static inline bool is_module_percpu_address(unsigned long addr)
794 {
795 	return false;
796 }
797 
798 static inline bool __is_module_percpu_address(unsigned long addr, unsigned long *can_addr)
799 {
800 	return false;
801 }
802 
803 static inline bool is_module_text_address(unsigned long addr)
804 {
805 	return false;
806 }
807 
808 static inline bool within_module_core(unsigned long addr,
809 				      const struct module *mod)
810 {
811 	return false;
812 }
813 
814 static inline bool within_module_init(unsigned long addr,
815 				      const struct module *mod)
816 {
817 	return false;
818 }
819 
820 static inline bool within_module(unsigned long addr, const struct module *mod)
821 {
822 	return false;
823 }
824 
825 /* Get/put a kernel symbol (calls should be symmetric) */
826 #define symbol_get(x) ({ extern typeof(x) x __attribute__((weak,visibility("hidden"))); &(x); })
827 #define symbol_put(x) do { } while (0)
828 #define symbol_put_addr(x) do { } while (0)
829 
830 static inline void __module_get(struct module *module)
831 {
832 }
833 
834 static inline bool try_module_get(struct module *module)
835 {
836 	return true;
837 }
838 
839 static inline void module_put(struct module *module)
840 {
841 }
842 
843 #define module_name(mod) "kernel"
844 
845 static inline int register_module_notifier(struct notifier_block *nb)
846 {
847 	/* no events will happen anyway, so this can always succeed */
848 	return 0;
849 }
850 
851 static inline int unregister_module_notifier(struct notifier_block *nb)
852 {
853 	return 0;
854 }
855 
856 #define module_put_and_kthread_exit(code) kthread_exit(code)
857 
858 static inline void print_modules(void)
859 {
860 }
861 
862 static inline bool module_requested_async_probing(struct module *module)
863 {
864 	return false;
865 }
866 
867 
868 static inline void set_module_sig_enforced(void)
869 {
870 }
871 
872 /* Dereference module function descriptor */
873 static inline
874 void *dereference_module_function_descriptor(struct module *mod, void *ptr)
875 {
876 	return ptr;
877 }
878 
879 static inline bool module_is_coming(struct module *mod)
880 {
881 	return false;
882 }
883 
884 static inline void *module_writable_address(struct module *mod, void *loc)
885 {
886 	return loc;
887 }
888 #endif /* CONFIG_MODULES */
889 
890 #ifdef CONFIG_SYSFS
891 extern struct kset *module_kset;
892 extern const struct kobj_type module_ktype;
893 #endif /* CONFIG_SYSFS */
894 
895 #define symbol_request(x) try_then_request_module(symbol_get(x), "symbol:" #x)
896 
897 /* BELOW HERE ALL THESE ARE OBSOLETE AND WILL VANISH */
898 
899 #define __MODULE_STRING(x) __stringify(x)
900 
901 #ifdef CONFIG_GENERIC_BUG
902 void module_bug_finalize(const Elf_Ehdr *, const Elf_Shdr *,
903 			 struct module *);
904 void module_bug_cleanup(struct module *);
905 
906 #else	/* !CONFIG_GENERIC_BUG */
907 
908 static inline void module_bug_finalize(const Elf_Ehdr *hdr,
909 					const Elf_Shdr *sechdrs,
910 					struct module *mod)
911 {
912 }
913 static inline void module_bug_cleanup(struct module *mod) {}
914 #endif	/* CONFIG_GENERIC_BUG */
915 
916 #ifdef CONFIG_MITIGATION_RETPOLINE
917 extern bool retpoline_module_ok(bool has_retpoline);
918 #else
919 static inline bool retpoline_module_ok(bool has_retpoline)
920 {
921 	return true;
922 }
923 #endif
924 
925 #ifdef CONFIG_MODULE_SIG
926 bool is_module_sig_enforced(void);
927 
928 static inline bool module_sig_ok(struct module *module)
929 {
930 	return module->sig_ok;
931 }
932 #else	/* !CONFIG_MODULE_SIG */
933 static inline bool is_module_sig_enforced(void)
934 {
935 	return false;
936 }
937 
938 static inline bool module_sig_ok(struct module *module)
939 {
940 	return true;
941 }
942 #endif	/* CONFIG_MODULE_SIG */
943 
944 #if defined(CONFIG_MODULES) && defined(CONFIG_KALLSYMS)
945 int module_kallsyms_on_each_symbol(const char *modname,
946 				   int (*fn)(void *, const char *, unsigned long),
947 				   void *data);
948 
949 /* For kallsyms to ask for address resolution.  namebuf should be at
950  * least KSYM_NAME_LEN long: a pointer to namebuf is returned if
951  * found, otherwise NULL.
952  */
953 int module_address_lookup(unsigned long addr,
954 			  unsigned long *symbolsize,
955 			  unsigned long *offset,
956 			  char **modname, const unsigned char **modbuildid,
957 			  char *namebuf);
958 int lookup_module_symbol_name(unsigned long addr, char *symname);
959 int lookup_module_symbol_attrs(unsigned long addr,
960 			       unsigned long *size,
961 			       unsigned long *offset,
962 			       char *modname,
963 			       char *name);
964 
965 /* Returns 0 and fills in value, defined and namebuf, or -ERANGE if
966  * symnum out of range.
967  */
968 int module_get_kallsym(unsigned int symnum, unsigned long *value, char *type,
969 		       char *name, char *module_name, int *exported);
970 
971 /* Look for this name: can be of form module:name. */
972 unsigned long module_kallsyms_lookup_name(const char *name);
973 
974 unsigned long find_kallsyms_symbol_value(struct module *mod, const char *name);
975 
976 #else	/* CONFIG_MODULES && CONFIG_KALLSYMS */
977 
978 static inline int module_kallsyms_on_each_symbol(const char *modname,
979 						 int (*fn)(void *, const char *, unsigned long),
980 						 void *data)
981 {
982 	return -EOPNOTSUPP;
983 }
984 
985 /* For kallsyms to ask for address resolution.  NULL means not found. */
986 static inline int module_address_lookup(unsigned long addr,
987 						unsigned long *symbolsize,
988 						unsigned long *offset,
989 						char **modname,
990 						const unsigned char **modbuildid,
991 						char *namebuf)
992 {
993 	return 0;
994 }
995 
996 static inline int lookup_module_symbol_name(unsigned long addr, char *symname)
997 {
998 	return -ERANGE;
999 }
1000 
1001 static inline int module_get_kallsym(unsigned int symnum, unsigned long *value,
1002 				     char *type, char *name,
1003 				     char *module_name, int *exported)
1004 {
1005 	return -ERANGE;
1006 }
1007 
1008 static inline unsigned long module_kallsyms_lookup_name(const char *name)
1009 {
1010 	return 0;
1011 }
1012 
1013 static inline unsigned long find_kallsyms_symbol_value(struct module *mod,
1014 						       const char *name)
1015 {
1016 	return 0;
1017 }
1018 
1019 #endif  /* CONFIG_MODULES && CONFIG_KALLSYMS */
1020 
1021 #endif /* _LINUX_MODULE_H */
1022