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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
38struct modversion_info {
39 unsigned long crc;
40 char name[MODULE_NAME_LEN];
41};
42
43struct module;
44struct exception_table_entry;
45
46struct 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
54struct 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
65struct module_version_attribute {
66 struct module_attribute mattr;
67 const char *module_name;
68 const char *version;
69};
70
71extern ssize_t __modver_version_show(const struct module_attribute *,
72 struct module_kobject *, char *);
73
74extern const struct module_attribute module_uevent;
75
76/* These are either module local, or the kernel's dummy ones. */
77extern int init_module(void);
78extern 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#define __INIT_OR_MODULE .text
155#define __INITDATA_OR_MODULE .data
156#define __INITRODATA_OR_MODULE .section ".rodata","a",%progbits
157#else
158#define __init_or_module __init
159#define __initdata_or_module __initdata
160#define __initconst_or_module __initconst
161#define __INIT_OR_MODULE __INIT
162#define __INITDATA_OR_MODULE __INITDATA
163#define __INITRODATA_OR_MODULE __INITRODATA
164#endif /*CONFIG_MODULES*/
165
166struct module_kobject *lookup_or_create_module_kobject(const char *name);
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/*
248 * Format: __mod_device_table__kmod_<modname>__<type>__<name>
249 * Parts of the string `__kmod_` and `__` are used as delimiters when parsing
250 * a symbol in file2alias.c
251 */
252#define __mod_device_table(type, name) \
253 __PASTE(__mod_device_table__, \
254 __PASTE(kmod_, \
255 __PASTE(__KBUILD_MODNAME, \
256 __PASTE(__, \
257 __PASTE(type, \
258 __PASTE(__, name))))))
259
260/* Creates an alias so file2alias.c can find device table. */
261#define MODULE_DEVICE_TABLE(type, name) \
262static typeof(name) __mod_device_table(type, name) \
263 __attribute__ ((used, alias(__stringify(name))))
264
265/* Version of form [<epoch>:]<version>[-<extra-version>].
266 * Or for CVS/RCS ID version, everything but the number is stripped.
267 * <epoch>: A (small) unsigned integer which allows you to start versions
268 * anew. If not mentioned, it's zero. eg. "2:1.0" is after
269 * "1:2.0".
270
271 * <version>: The <version> may contain only alphanumerics and the
272 * character `.'. Ordered by numeric sort for numeric parts,
273 * ascii sort for ascii parts (as per RPM or DEB algorithm).
274
275 * <extraversion>: Like <version>, but inserted for local
276 * customizations, eg "rh3" or "rusty1".
277
278 * Using this automatically adds a checksum of the .c files and the
279 * local headers in "srcversion".
280 */
281
282#if defined(MODULE) || !defined(CONFIG_SYSFS)
283#define MODULE_VERSION(_version) MODULE_INFO(version, _version)
284#else
285#define MODULE_VERSION(_version) \
286 MODULE_INFO(version, _version); \
287 static const struct module_version_attribute __modver_attr \
288 __used __section("__modver") \
289 __aligned(__alignof__(struct module_version_attribute)) \
290 = { \
291 .mattr = { \
292 .attr = { \
293 .name = "version", \
294 .mode = S_IRUGO, \
295 }, \
296 .show = __modver_version_show, \
297 }, \
298 .module_name = KBUILD_MODNAME, \
299 .version = _version, \
300 }
301#endif
302
303/* Optional firmware file (or files) needed by the module
304 * format is simply firmware file name. Multiple firmware
305 * files require multiple MODULE_FIRMWARE() specifiers */
306#define MODULE_FIRMWARE(_firmware) MODULE_INFO(firmware, _firmware)
307
308#define MODULE_IMPORT_NS(ns) MODULE_INFO(import_ns, ns)
309
310struct notifier_block;
311
312enum module_state {
313 MODULE_STATE_LIVE, /* Normal state. */
314 MODULE_STATE_COMING, /* Full formed, running module_init. */
315 MODULE_STATE_GOING, /* Going away. */
316 MODULE_STATE_UNFORMED, /* Still setting it up. */
317};
318
319struct mod_tree_node {
320 struct module *mod;
321 struct latch_tree_node node;
322};
323
324enum mod_mem_type {
325 MOD_TEXT = 0,
326 MOD_DATA,
327 MOD_RODATA,
328 MOD_RO_AFTER_INIT,
329 MOD_INIT_TEXT,
330 MOD_INIT_DATA,
331 MOD_INIT_RODATA,
332
333 MOD_MEM_NUM_TYPES,
334 MOD_INVALID = -1,
335};
336
337#define mod_mem_type_is_init(type) \
338 ((type) == MOD_INIT_TEXT || \
339 (type) == MOD_INIT_DATA || \
340 (type) == MOD_INIT_RODATA)
341
342#define mod_mem_type_is_core(type) (!mod_mem_type_is_init(type))
343
344#define mod_mem_type_is_text(type) \
345 ((type) == MOD_TEXT || \
346 (type) == MOD_INIT_TEXT)
347
348#define mod_mem_type_is_data(type) (!mod_mem_type_is_text(type))
349
350#define mod_mem_type_is_core_data(type) \
351 (mod_mem_type_is_core(type) && \
352 mod_mem_type_is_data(type))
353
354#define for_each_mod_mem_type(type) \
355 for (enum mod_mem_type (type) = 0; \
356 (type) < MOD_MEM_NUM_TYPES; (type)++)
357
358#define for_class_mod_mem_type(type, class) \
359 for_each_mod_mem_type(type) \
360 if (mod_mem_type_is_##class(type))
361
362struct module_memory {
363 void *base;
364 bool is_rox;
365 unsigned int size;
366
367#ifdef CONFIG_MODULES_TREE_LOOKUP
368 struct mod_tree_node mtn;
369#endif
370};
371
372#ifdef CONFIG_MODULES_TREE_LOOKUP
373/* Only touch one cacheline for common rbtree-for-core-layout case. */
374#define __module_memory_align ____cacheline_aligned
375#else
376#define __module_memory_align
377#endif
378
379struct mod_kallsyms {
380 Elf_Sym *symtab;
381 unsigned int num_symtab;
382 char *strtab;
383 char *typetab;
384};
385
386#ifdef CONFIG_LIVEPATCH
387/**
388 * struct klp_modinfo - ELF information preserved from the livepatch module
389 *
390 * @hdr: ELF header
391 * @sechdrs: Section header table
392 * @secstrings: String table for the section headers
393 * @symndx: The symbol table section index
394 */
395struct klp_modinfo {
396 Elf_Ehdr hdr;
397 Elf_Shdr *sechdrs;
398 char *secstrings;
399 unsigned int symndx;
400};
401#endif
402
403struct module {
404 enum module_state state;
405
406 /* Member of list of modules */
407 struct list_head list;
408
409 /* Unique handle for this module */
410 char name[MODULE_NAME_LEN];
411
412#ifdef CONFIG_STACKTRACE_BUILD_ID
413 /* Module build ID */
414 unsigned char build_id[BUILD_ID_SIZE_MAX];
415#endif
416
417 /* Sysfs stuff. */
418 struct module_kobject mkobj;
419 struct module_attribute *modinfo_attrs;
420 const char *version;
421 const char *srcversion;
422 struct kobject *holders_dir;
423
424 /* Exported symbols */
425 const struct kernel_symbol *syms;
426 const u32 *crcs;
427 unsigned int num_syms;
428
429#ifdef CONFIG_ARCH_USES_CFI_TRAPS
430 s32 *kcfi_traps;
431 s32 *kcfi_traps_end;
432#endif
433
434 /* Kernel parameters. */
435#ifdef CONFIG_SYSFS
436 struct mutex param_lock;
437#endif
438 struct kernel_param *kp;
439 unsigned int num_kp;
440
441 /* GPL-only exported symbols. */
442 unsigned int num_gpl_syms;
443 const struct kernel_symbol *gpl_syms;
444 const u32 *gpl_crcs;
445 bool using_gplonly_symbols;
446
447#ifdef CONFIG_MODULE_SIG
448 /* Signature was verified. */
449 bool sig_ok;
450#endif
451
452 bool async_probe_requested;
453
454 /* Exception table */
455 unsigned int num_exentries;
456 struct exception_table_entry *extable;
457
458 /* Startup function. */
459 int (*init)(void);
460
461 struct module_memory mem[MOD_MEM_NUM_TYPES] __module_memory_align;
462
463 /* Arch-specific module values */
464 struct mod_arch_specific arch;
465
466 unsigned long taints; /* same bits as kernel:taint_flags */
467
468#ifdef CONFIG_GENERIC_BUG
469 /* Support for BUG */
470 unsigned num_bugs;
471 struct list_head bug_list;
472 struct bug_entry *bug_table;
473#endif
474
475#ifdef CONFIG_KALLSYMS
476 /* Protected by RCU and/or module_mutex: use rcu_dereference() */
477 struct mod_kallsyms __rcu *kallsyms;
478 struct mod_kallsyms core_kallsyms;
479
480 /* Section attributes */
481 struct module_sect_attrs *sect_attrs;
482
483 /* Notes attributes */
484 struct module_notes_attrs *notes_attrs;
485#endif
486
487 /* The command line arguments (may be mangled). People like
488 keeping pointers to this stuff */
489 char *args;
490
491#ifdef CONFIG_SMP
492 /* Per-cpu data. */
493 void __percpu *percpu;
494 unsigned int percpu_size;
495#endif
496 void *noinstr_text_start;
497 unsigned int noinstr_text_size;
498
499#ifdef CONFIG_TRACEPOINTS
500 unsigned int num_tracepoints;
501 tracepoint_ptr_t *tracepoints_ptrs;
502#endif
503#ifdef CONFIG_TREE_SRCU
504 unsigned int num_srcu_structs;
505 struct srcu_struct **srcu_struct_ptrs;
506#endif
507#ifdef CONFIG_BPF_EVENTS
508 unsigned int num_bpf_raw_events;
509 struct bpf_raw_event_map *bpf_raw_events;
510#endif
511#ifdef CONFIG_DEBUG_INFO_BTF_MODULES
512 unsigned int btf_data_size;
513 unsigned int btf_base_data_size;
514 void *btf_data;
515 void *btf_base_data;
516#endif
517#ifdef CONFIG_JUMP_LABEL
518 struct jump_entry *jump_entries;
519 unsigned int num_jump_entries;
520#endif
521#ifdef CONFIG_TRACING
522 unsigned int num_trace_bprintk_fmt;
523 const char **trace_bprintk_fmt_start;
524#endif
525#ifdef CONFIG_EVENT_TRACING
526 struct trace_event_call **trace_events;
527 unsigned int num_trace_events;
528 struct trace_eval_map **trace_evals;
529 unsigned int num_trace_evals;
530#endif
531#ifdef CONFIG_DYNAMIC_FTRACE
532 unsigned int num_ftrace_callsites;
533 unsigned long *ftrace_callsites;
534#endif
535#ifdef CONFIG_KPROBES
536 void *kprobes_text_start;
537 unsigned int kprobes_text_size;
538 unsigned long *kprobe_blacklist;
539 unsigned int num_kprobe_blacklist;
540#endif
541#ifdef CONFIG_HAVE_STATIC_CALL_INLINE
542 int num_static_call_sites;
543 struct static_call_site *static_call_sites;
544#endif
545#if IS_ENABLED(CONFIG_KUNIT)
546 int num_kunit_init_suites;
547 struct kunit_suite **kunit_init_suites;
548 int num_kunit_suites;
549 struct kunit_suite **kunit_suites;
550#endif
551
552
553#ifdef CONFIG_LIVEPATCH
554 bool klp; /* Is this a livepatch module? */
555 bool klp_alive;
556
557 /* ELF information */
558 struct klp_modinfo *klp_info;
559#endif
560
561#ifdef CONFIG_PRINTK_INDEX
562 unsigned int printk_index_size;
563 struct pi_entry **printk_index_start;
564#endif
565
566#ifdef CONFIG_MODULE_UNLOAD
567 /* What modules depend on me? */
568 struct list_head source_list;
569 /* What modules do I depend on? */
570 struct list_head target_list;
571
572 /* Destruction function. */
573 void (*exit)(void);
574
575 atomic_t refcnt;
576#endif
577
578#ifdef CONFIG_CONSTRUCTORS
579 /* Constructor functions. */
580 ctor_fn_t *ctors;
581 unsigned int num_ctors;
582#endif
583
584#ifdef CONFIG_FUNCTION_ERROR_INJECTION
585 struct error_injection_entry *ei_funcs;
586 unsigned int num_ei_funcs;
587#endif
588#ifdef CONFIG_DYNAMIC_DEBUG_CORE
589 struct _ddebug_info dyndbg_info;
590#endif
591} ____cacheline_aligned __randomize_layout;
592#ifndef MODULE_ARCH_INIT
593#define MODULE_ARCH_INIT {}
594#endif
595
596#ifdef CONFIG_MODULES
597
598/* Get/put a kernel symbol (calls must be symmetric) */
599void *__symbol_get(const char *symbol);
600void *__symbol_get_gpl(const char *symbol);
601#define symbol_get(x) ({ \
602 static const char __notrim[] \
603 __used __section(".no_trim_symbol") = __stringify(x); \
604 (typeof(&x))(__symbol_get(__stringify(x))); })
605
606#ifndef HAVE_ARCH_KALLSYMS_SYMBOL_VALUE
607static inline unsigned long kallsyms_symbol_value(const Elf_Sym *sym)
608{
609 return sym->st_value;
610}
611#endif
612
613/* FIXME: It'd be nice to isolate modules during init, too, so they
614 aren't used before they (may) fail. But presently too much code
615 (IDE & SCSI) require entry into the module during init.*/
616static inline bool module_is_live(struct module *mod)
617{
618 return mod->state != MODULE_STATE_GOING;
619}
620
621static inline bool module_is_coming(struct module *mod)
622{
623 return mod->state == MODULE_STATE_COMING;
624}
625
626struct module *__module_text_address(unsigned long addr);
627struct module *__module_address(unsigned long addr);
628bool is_module_address(unsigned long addr);
629bool __is_module_percpu_address(unsigned long addr, unsigned long *can_addr);
630bool is_module_percpu_address(unsigned long addr);
631bool is_module_text_address(unsigned long addr);
632
633static inline bool within_module_mem_type(unsigned long addr,
634 const struct module *mod,
635 enum mod_mem_type type)
636{
637 unsigned long base, size;
638
639 base = (unsigned long)mod->mem[type].base;
640 size = mod->mem[type].size;
641 return addr - base < size;
642}
643
644static inline bool within_module_core(unsigned long addr,
645 const struct module *mod)
646{
647 for_class_mod_mem_type(type, core) {
648 if (within_module_mem_type(addr, mod, type))
649 return true;
650 }
651 return false;
652}
653
654static inline bool within_module_init(unsigned long addr,
655 const struct module *mod)
656{
657 for_class_mod_mem_type(type, init) {
658 if (within_module_mem_type(addr, mod, type))
659 return true;
660 }
661 return false;
662}
663
664static inline bool within_module(unsigned long addr, const struct module *mod)
665{
666 return within_module_init(addr, mod) || within_module_core(addr, mod);
667}
668
669/* Search for module by name: must be in a RCU critical section. */
670struct module *find_module(const char *name);
671
672extern void __noreturn __module_put_and_kthread_exit(struct module *mod,
673 long code);
674#define module_put_and_kthread_exit(code) __module_put_and_kthread_exit(THIS_MODULE, code)
675
676#ifdef CONFIG_MODULE_UNLOAD
677int module_refcount(struct module *mod);
678void __symbol_put(const char *symbol);
679#define symbol_put(x) __symbol_put(__stringify(x))
680void symbol_put_addr(void *addr);
681
682/* Sometimes we know we already have a refcount, and it's easier not
683 to handle the error case (which only happens with rmmod --wait). */
684extern void __module_get(struct module *module);
685
686/**
687 * try_module_get() - take module refcount unless module is being removed
688 * @module: the module we should check for
689 *
690 * Only try to get a module reference count if the module is not being removed.
691 * This call will fail if the module is in the process of being removed.
692 *
693 * Care must also be taken to ensure the module exists and is alive prior to
694 * usage of this call. This can be gauranteed through two means:
695 *
696 * 1) Direct protection: you know an earlier caller must have increased the
697 * module reference through __module_get(). This can typically be achieved
698 * by having another entity other than the module itself increment the
699 * module reference count.
700 *
701 * 2) Implied protection: there is an implied protection against module
702 * removal. An example of this is the implied protection used by kernfs /
703 * sysfs. The sysfs store / read file operations are guaranteed to exist
704 * through the use of kernfs's active reference (see kernfs_active()) and a
705 * sysfs / kernfs file removal cannot happen unless the same file is not
706 * active. Therefore, if a sysfs file is being read or written to the module
707 * which created it must still exist. It is therefore safe to use
708 * try_module_get() on module sysfs store / read ops.
709 *
710 * One of the real values to try_module_get() is the module_is_live() check
711 * which ensures that the caller of try_module_get() can yield to userspace
712 * module removal requests and gracefully fail if the module is on its way out.
713 *
714 * Returns true if the reference count was successfully incremented.
715 */
716extern bool try_module_get(struct module *module);
717
718/**
719 * module_put() - release a reference count to a module
720 * @module: the module we should release a reference count for
721 *
722 * If you successfully bump a reference count to a module with try_module_get(),
723 * when you are finished you must call module_put() to release that reference
724 * count.
725 */
726extern void module_put(struct module *module);
727
728#else /*!CONFIG_MODULE_UNLOAD*/
729static inline bool try_module_get(struct module *module)
730{
731 return !module || module_is_live(module);
732}
733static inline void module_put(struct module *module)
734{
735}
736static inline void __module_get(struct module *module)
737{
738}
739#define symbol_put(x) do { } while (0)
740#define symbol_put_addr(p) do { } while (0)
741
742#endif /* CONFIG_MODULE_UNLOAD */
743
744/* This is a #define so the string doesn't get put in every .o file */
745#define module_name(mod) \
746({ \
747 struct module *__mod = (mod); \
748 __mod ? __mod->name : "kernel"; \
749})
750
751/* Dereference module function descriptor */
752void *dereference_module_function_descriptor(struct module *mod, void *ptr);
753
754int register_module_notifier(struct notifier_block *nb);
755int unregister_module_notifier(struct notifier_block *nb);
756
757extern void print_modules(void);
758
759static inline bool module_requested_async_probing(struct module *module)
760{
761 return module && module->async_probe_requested;
762}
763
764static inline bool is_livepatch_module(struct module *mod)
765{
766#ifdef CONFIG_LIVEPATCH
767 return mod->klp;
768#else
769 return false;
770#endif
771}
772
773void set_module_sig_enforced(void);
774
775void module_for_each_mod(int(*func)(struct module *mod, void *data), void *data);
776
777#else /* !CONFIG_MODULES... */
778
779static inline struct module *__module_address(unsigned long addr)
780{
781 return NULL;
782}
783
784static inline struct module *__module_text_address(unsigned long addr)
785{
786 return NULL;
787}
788
789static inline bool is_module_address(unsigned long addr)
790{
791 return false;
792}
793
794static inline bool is_module_percpu_address(unsigned long addr)
795{
796 return false;
797}
798
799static inline bool __is_module_percpu_address(unsigned long addr, unsigned long *can_addr)
800{
801 return false;
802}
803
804static inline bool is_module_text_address(unsigned long addr)
805{
806 return false;
807}
808
809static inline bool within_module_core(unsigned long addr,
810 const struct module *mod)
811{
812 return false;
813}
814
815static inline bool within_module_init(unsigned long addr,
816 const struct module *mod)
817{
818 return false;
819}
820
821static 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
831static inline void __module_get(struct module *module)
832{
833}
834
835static inline bool try_module_get(struct module *module)
836{
837 return true;
838}
839
840static inline void module_put(struct module *module)
841{
842}
843
844#define module_name(mod) "kernel"
845
846static 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
852static 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
859static inline void print_modules(void)
860{
861}
862
863static inline bool module_requested_async_probing(struct module *module)
864{
865 return false;
866}
867
868
869static inline void set_module_sig_enforced(void)
870{
871}
872
873/* Dereference module function descriptor */
874static inline
875void *dereference_module_function_descriptor(struct module *mod, void *ptr)
876{
877 return ptr;
878}
879
880static inline bool module_is_coming(struct module *mod)
881{
882 return false;
883}
884
885static inline void module_for_each_mod(int(*func)(struct module *mod, void *data), void *data)
886{
887}
888#endif /* CONFIG_MODULES */
889
890#ifdef CONFIG_SYSFS
891extern struct kset *module_kset;
892extern 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
902void module_bug_finalize(const Elf_Ehdr *, const Elf_Shdr *,
903 struct module *);
904void module_bug_cleanup(struct module *);
905
906#else /* !CONFIG_GENERIC_BUG */
907
908static inline void module_bug_finalize(const Elf_Ehdr *hdr,
909 const Elf_Shdr *sechdrs,
910 struct module *mod)
911{
912}
913static inline void module_bug_cleanup(struct module *mod) {}
914#endif /* CONFIG_GENERIC_BUG */
915
916#ifdef CONFIG_MITIGATION_RETPOLINE
917extern bool retpoline_module_ok(bool has_retpoline);
918#else
919static inline bool retpoline_module_ok(bool has_retpoline)
920{
921 return true;
922}
923#endif
924
925#ifdef CONFIG_MODULE_SIG
926bool is_module_sig_enforced(void);
927
928static inline bool module_sig_ok(struct module *module)
929{
930 return module->sig_ok;
931}
932#else /* !CONFIG_MODULE_SIG */
933static inline bool is_module_sig_enforced(void)
934{
935 return false;
936}
937
938static 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)
945int 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 */
953int module_address_lookup(unsigned long addr,
954 unsigned long *symbolsize,
955 unsigned long *offset,
956 char **modname, const unsigned char **modbuildid,
957 char *namebuf);
958int lookup_module_symbol_name(unsigned long addr, char *symname);
959int 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 */
968int 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. */
972unsigned long module_kallsyms_lookup_name(const char *name);
973
974unsigned long find_kallsyms_symbol_value(struct module *mod, const char *name);
975
976#else /* CONFIG_MODULES && CONFIG_KALLSYMS */
977
978static 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. */
986static 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
996static inline int lookup_module_symbol_name(unsigned long addr, char *symname)
997{
998 return -ERANGE;
999}
1000
1001static 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
1008static inline unsigned long module_kallsyms_lookup_name(const char *name)
1009{
1010 return 0;
1011}
1012
1013static 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/* Define __free(module_put) macro for struct module *. */
1022DEFINE_FREE(module_put, struct module *, if (_T) module_put(_T))
1023
1024#endif /* _LINUX_MODULE_H */