Linux kernel mirror (for testing)
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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/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
37struct modversion_info {
38 unsigned long crc;
39 char name[MODULE_NAME_LEN];
40};
41
42struct module;
43struct exception_table_entry;
44
45struct 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
53struct 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
64struct module_version_attribute {
65 struct module_attribute mattr;
66 const char *module_name;
67 const char *version;
68};
69
70extern ssize_t __modver_version_show(const struct module_attribute *,
71 struct module_kobject *, char *);
72
73extern const struct module_attribute module_uevent;
74
75/* These are either module local, or the kernel's dummy ones. */
76extern int init_module(void);
77extern 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) \
250extern 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
301struct notifier_block;
302
303#ifdef CONFIG_MODULES
304
305extern int modules_disabled; /* for sysctl */
306/* Get/put a kernel symbol (calls must be symmetric) */
307void *__symbol_get(const char *symbol);
308void *__symbol_get_gpl(const char *symbol);
309#define symbol_get(x) ({ \
310 static const char __notrim[] \
311 __used __section(".no_trim_symbol") = __stringify(x); \
312 (typeof(&x))(__symbol_get(__stringify(x))); })
313
314/* modules using other modules: kdb wants to see this. */
315struct module_use {
316 struct list_head source_list;
317 struct list_head target_list;
318 struct module *source, *target;
319};
320
321enum module_state {
322 MODULE_STATE_LIVE, /* Normal state. */
323 MODULE_STATE_COMING, /* Full formed, running module_init. */
324 MODULE_STATE_GOING, /* Going away. */
325 MODULE_STATE_UNFORMED, /* Still setting it up. */
326};
327
328struct mod_tree_node {
329 struct module *mod;
330 struct latch_tree_node node;
331};
332
333enum mod_mem_type {
334 MOD_TEXT = 0,
335 MOD_DATA,
336 MOD_RODATA,
337 MOD_RO_AFTER_INIT,
338 MOD_INIT_TEXT,
339 MOD_INIT_DATA,
340 MOD_INIT_RODATA,
341
342 MOD_MEM_NUM_TYPES,
343 MOD_INVALID = -1,
344};
345
346#define mod_mem_type_is_init(type) \
347 ((type) == MOD_INIT_TEXT || \
348 (type) == MOD_INIT_DATA || \
349 (type) == MOD_INIT_RODATA)
350
351#define mod_mem_type_is_core(type) (!mod_mem_type_is_init(type))
352
353#define mod_mem_type_is_text(type) \
354 ((type) == MOD_TEXT || \
355 (type) == MOD_INIT_TEXT)
356
357#define mod_mem_type_is_data(type) (!mod_mem_type_is_text(type))
358
359#define mod_mem_type_is_core_data(type) \
360 (mod_mem_type_is_core(type) && \
361 mod_mem_type_is_data(type))
362
363#define for_each_mod_mem_type(type) \
364 for (enum mod_mem_type (type) = 0; \
365 (type) < MOD_MEM_NUM_TYPES; (type)++)
366
367#define for_class_mod_mem_type(type, class) \
368 for_each_mod_mem_type(type) \
369 if (mod_mem_type_is_##class(type))
370
371struct module_memory {
372 void *base;
373 void *rw_copy;
374 bool is_rox;
375 unsigned int size;
376
377#ifdef CONFIG_MODULES_TREE_LOOKUP
378 struct mod_tree_node mtn;
379#endif
380};
381
382#ifdef CONFIG_MODULES_TREE_LOOKUP
383/* Only touch one cacheline for common rbtree-for-core-layout case. */
384#define __module_memory_align ____cacheline_aligned
385#else
386#define __module_memory_align
387#endif
388
389struct mod_kallsyms {
390 Elf_Sym *symtab;
391 unsigned int num_symtab;
392 char *strtab;
393 char *typetab;
394};
395
396#ifdef CONFIG_LIVEPATCH
397/**
398 * struct klp_modinfo - ELF information preserved from the livepatch module
399 *
400 * @hdr: ELF header
401 * @sechdrs: Section header table
402 * @secstrings: String table for the section headers
403 * @symndx: The symbol table section index
404 */
405struct klp_modinfo {
406 Elf_Ehdr hdr;
407 Elf_Shdr *sechdrs;
408 char *secstrings;
409 unsigned int symndx;
410};
411#endif
412
413struct module {
414 enum module_state state;
415
416 /* Member of list of modules */
417 struct list_head list;
418
419 /* Unique handle for this module */
420 char name[MODULE_NAME_LEN];
421
422#ifdef CONFIG_STACKTRACE_BUILD_ID
423 /* Module build ID */
424 unsigned char build_id[BUILD_ID_SIZE_MAX];
425#endif
426
427 /* Sysfs stuff. */
428 struct module_kobject mkobj;
429 struct module_attribute *modinfo_attrs;
430 const char *version;
431 const char *srcversion;
432 struct kobject *holders_dir;
433
434 /* Exported symbols */
435 const struct kernel_symbol *syms;
436 const u32 *crcs;
437 unsigned int num_syms;
438
439#ifdef CONFIG_ARCH_USES_CFI_TRAPS
440 s32 *kcfi_traps;
441 s32 *kcfi_traps_end;
442#endif
443
444 /* Kernel parameters. */
445#ifdef CONFIG_SYSFS
446 struct mutex param_lock;
447#endif
448 struct kernel_param *kp;
449 unsigned int num_kp;
450
451 /* GPL-only exported symbols. */
452 unsigned int num_gpl_syms;
453 const struct kernel_symbol *gpl_syms;
454 const u32 *gpl_crcs;
455 bool using_gplonly_symbols;
456
457#ifdef CONFIG_MODULE_SIG
458 /* Signature was verified. */
459 bool sig_ok;
460#endif
461
462 bool async_probe_requested;
463
464 /* Exception table */
465 unsigned int num_exentries;
466 struct exception_table_entry *extable;
467
468 /* Startup function. */
469 int (*init)(void);
470
471 struct module_memory mem[MOD_MEM_NUM_TYPES] __module_memory_align;
472
473 /* Arch-specific module values */
474 struct mod_arch_specific arch;
475
476 unsigned long taints; /* same bits as kernel:taint_flags */
477
478#ifdef CONFIG_GENERIC_BUG
479 /* Support for BUG */
480 unsigned num_bugs;
481 struct list_head bug_list;
482 struct bug_entry *bug_table;
483#endif
484
485#ifdef CONFIG_KALLSYMS
486 /* Protected by RCU and/or module_mutex: use rcu_dereference() */
487 struct mod_kallsyms __rcu *kallsyms;
488 struct mod_kallsyms core_kallsyms;
489
490 /* Section attributes */
491 struct module_sect_attrs *sect_attrs;
492
493 /* Notes attributes */
494 struct module_notes_attrs *notes_attrs;
495#endif
496
497 /* The command line arguments (may be mangled). People like
498 keeping pointers to this stuff */
499 char *args;
500
501#ifdef CONFIG_SMP
502 /* Per-cpu data. */
503 void __percpu *percpu;
504 unsigned int percpu_size;
505#endif
506 void *noinstr_text_start;
507 unsigned int noinstr_text_size;
508
509#ifdef CONFIG_TRACEPOINTS
510 unsigned int num_tracepoints;
511 tracepoint_ptr_t *tracepoints_ptrs;
512#endif
513#ifdef CONFIG_TREE_SRCU
514 unsigned int num_srcu_structs;
515 struct srcu_struct **srcu_struct_ptrs;
516#endif
517#ifdef CONFIG_BPF_EVENTS
518 unsigned int num_bpf_raw_events;
519 struct bpf_raw_event_map *bpf_raw_events;
520#endif
521#ifdef CONFIG_DEBUG_INFO_BTF_MODULES
522 unsigned int btf_data_size;
523 unsigned int btf_base_data_size;
524 void *btf_data;
525 void *btf_base_data;
526#endif
527#ifdef CONFIG_JUMP_LABEL
528 struct jump_entry *jump_entries;
529 unsigned int num_jump_entries;
530#endif
531#ifdef CONFIG_TRACING
532 unsigned int num_trace_bprintk_fmt;
533 const char **trace_bprintk_fmt_start;
534#endif
535#ifdef CONFIG_EVENT_TRACING
536 struct trace_event_call **trace_events;
537 unsigned int num_trace_events;
538 struct trace_eval_map **trace_evals;
539 unsigned int num_trace_evals;
540#endif
541#ifdef CONFIG_FTRACE_MCOUNT_RECORD
542 unsigned int num_ftrace_callsites;
543 unsigned long *ftrace_callsites;
544#endif
545#ifdef CONFIG_KPROBES
546 void *kprobes_text_start;
547 unsigned int kprobes_text_size;
548 unsigned long *kprobe_blacklist;
549 unsigned int num_kprobe_blacklist;
550#endif
551#ifdef CONFIG_HAVE_STATIC_CALL_INLINE
552 int num_static_call_sites;
553 struct static_call_site *static_call_sites;
554#endif
555#if IS_ENABLED(CONFIG_KUNIT)
556 int num_kunit_init_suites;
557 struct kunit_suite **kunit_init_suites;
558 int num_kunit_suites;
559 struct kunit_suite **kunit_suites;
560#endif
561
562
563#ifdef CONFIG_LIVEPATCH
564 bool klp; /* Is this a livepatch module? */
565 bool klp_alive;
566
567 /* ELF information */
568 struct klp_modinfo *klp_info;
569#endif
570
571#ifdef CONFIG_PRINTK_INDEX
572 unsigned int printk_index_size;
573 struct pi_entry **printk_index_start;
574#endif
575
576#ifdef CONFIG_MODULE_UNLOAD
577 /* What modules depend on me? */
578 struct list_head source_list;
579 /* What modules do I depend on? */
580 struct list_head target_list;
581
582 /* Destruction function. */
583 void (*exit)(void);
584
585 atomic_t refcnt;
586#endif
587
588#ifdef CONFIG_CONSTRUCTORS
589 /* Constructor functions. */
590 ctor_fn_t *ctors;
591 unsigned int num_ctors;
592#endif
593
594#ifdef CONFIG_FUNCTION_ERROR_INJECTION
595 struct error_injection_entry *ei_funcs;
596 unsigned int num_ei_funcs;
597#endif
598#ifdef CONFIG_DYNAMIC_DEBUG_CORE
599 struct _ddebug_info dyndbg_info;
600#endif
601} ____cacheline_aligned __randomize_layout;
602#ifndef MODULE_ARCH_INIT
603#define MODULE_ARCH_INIT {}
604#endif
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-sched 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_writable_address(struct module *mod, void *loc);
776
777static inline void *module_writable_address(struct module *mod, void *loc)
778{
779 if (!IS_ENABLED(CONFIG_ARCH_HAS_EXECMEM_ROX) || !mod ||
780 mod->state != MODULE_STATE_UNFORMED)
781 return loc;
782 return __module_writable_address(mod, loc);
783}
784
785#else /* !CONFIG_MODULES... */
786
787static inline struct module *__module_address(unsigned long addr)
788{
789 return NULL;
790}
791
792static inline struct module *__module_text_address(unsigned long addr)
793{
794 return NULL;
795}
796
797static inline bool is_module_address(unsigned long addr)
798{
799 return false;
800}
801
802static inline bool is_module_percpu_address(unsigned long addr)
803{
804 return false;
805}
806
807static inline bool __is_module_percpu_address(unsigned long addr, unsigned long *can_addr)
808{
809 return false;
810}
811
812static inline bool is_module_text_address(unsigned long addr)
813{
814 return false;
815}
816
817static inline bool within_module_core(unsigned long addr,
818 const struct module *mod)
819{
820 return false;
821}
822
823static inline bool within_module_init(unsigned long addr,
824 const struct module *mod)
825{
826 return false;
827}
828
829static inline bool within_module(unsigned long addr, const struct module *mod)
830{
831 return false;
832}
833
834/* Get/put a kernel symbol (calls should be symmetric) */
835#define symbol_get(x) ({ extern typeof(x) x __attribute__((weak,visibility("hidden"))); &(x); })
836#define symbol_put(x) do { } while (0)
837#define symbol_put_addr(x) do { } while (0)
838
839static inline void __module_get(struct module *module)
840{
841}
842
843static inline bool try_module_get(struct module *module)
844{
845 return true;
846}
847
848static inline void module_put(struct module *module)
849{
850}
851
852#define module_name(mod) "kernel"
853
854static inline int register_module_notifier(struct notifier_block *nb)
855{
856 /* no events will happen anyway, so this can always succeed */
857 return 0;
858}
859
860static inline int unregister_module_notifier(struct notifier_block *nb)
861{
862 return 0;
863}
864
865#define module_put_and_kthread_exit(code) kthread_exit(code)
866
867static inline void print_modules(void)
868{
869}
870
871static inline bool module_requested_async_probing(struct module *module)
872{
873 return false;
874}
875
876
877static inline void set_module_sig_enforced(void)
878{
879}
880
881/* Dereference module function descriptor */
882static inline
883void *dereference_module_function_descriptor(struct module *mod, void *ptr)
884{
885 return ptr;
886}
887
888static inline bool module_is_coming(struct module *mod)
889{
890 return false;
891}
892
893static inline void *module_writable_address(struct module *mod, void *loc)
894{
895 return loc;
896}
897#endif /* CONFIG_MODULES */
898
899#ifdef CONFIG_SYSFS
900extern struct kset *module_kset;
901extern const struct kobj_type module_ktype;
902#endif /* CONFIG_SYSFS */
903
904#define symbol_request(x) try_then_request_module(symbol_get(x), "symbol:" #x)
905
906/* BELOW HERE ALL THESE ARE OBSOLETE AND WILL VANISH */
907
908#define __MODULE_STRING(x) __stringify(x)
909
910#ifdef CONFIG_GENERIC_BUG
911void module_bug_finalize(const Elf_Ehdr *, const Elf_Shdr *,
912 struct module *);
913void module_bug_cleanup(struct module *);
914
915#else /* !CONFIG_GENERIC_BUG */
916
917static inline void module_bug_finalize(const Elf_Ehdr *hdr,
918 const Elf_Shdr *sechdrs,
919 struct module *mod)
920{
921}
922static inline void module_bug_cleanup(struct module *mod) {}
923#endif /* CONFIG_GENERIC_BUG */
924
925#ifdef CONFIG_MITIGATION_RETPOLINE
926extern bool retpoline_module_ok(bool has_retpoline);
927#else
928static inline bool retpoline_module_ok(bool has_retpoline)
929{
930 return true;
931}
932#endif
933
934#ifdef CONFIG_MODULE_SIG
935bool is_module_sig_enforced(void);
936
937static inline bool module_sig_ok(struct module *module)
938{
939 return module->sig_ok;
940}
941#else /* !CONFIG_MODULE_SIG */
942static inline bool is_module_sig_enforced(void)
943{
944 return false;
945}
946
947static inline bool module_sig_ok(struct module *module)
948{
949 return true;
950}
951#endif /* CONFIG_MODULE_SIG */
952
953#if defined(CONFIG_MODULES) && defined(CONFIG_KALLSYMS)
954int module_kallsyms_on_each_symbol(const char *modname,
955 int (*fn)(void *, const char *, unsigned long),
956 void *data);
957
958/* For kallsyms to ask for address resolution. namebuf should be at
959 * least KSYM_NAME_LEN long: a pointer to namebuf is returned if
960 * found, otherwise NULL.
961 */
962int module_address_lookup(unsigned long addr,
963 unsigned long *symbolsize,
964 unsigned long *offset,
965 char **modname, const unsigned char **modbuildid,
966 char *namebuf);
967int lookup_module_symbol_name(unsigned long addr, char *symname);
968int lookup_module_symbol_attrs(unsigned long addr,
969 unsigned long *size,
970 unsigned long *offset,
971 char *modname,
972 char *name);
973
974/* Returns 0 and fills in value, defined and namebuf, or -ERANGE if
975 * symnum out of range.
976 */
977int module_get_kallsym(unsigned int symnum, unsigned long *value, char *type,
978 char *name, char *module_name, int *exported);
979
980/* Look for this name: can be of form module:name. */
981unsigned long module_kallsyms_lookup_name(const char *name);
982
983unsigned long find_kallsyms_symbol_value(struct module *mod, const char *name);
984
985#else /* CONFIG_MODULES && CONFIG_KALLSYMS */
986
987static inline int module_kallsyms_on_each_symbol(const char *modname,
988 int (*fn)(void *, const char *, unsigned long),
989 void *data)
990{
991 return -EOPNOTSUPP;
992}
993
994/* For kallsyms to ask for address resolution. NULL means not found. */
995static inline int module_address_lookup(unsigned long addr,
996 unsigned long *symbolsize,
997 unsigned long *offset,
998 char **modname,
999 const unsigned char **modbuildid,
1000 char *namebuf)
1001{
1002 return 0;
1003}
1004
1005static inline int lookup_module_symbol_name(unsigned long addr, char *symname)
1006{
1007 return -ERANGE;
1008}
1009
1010static inline int module_get_kallsym(unsigned int symnum, unsigned long *value,
1011 char *type, char *name,
1012 char *module_name, int *exported)
1013{
1014 return -ERANGE;
1015}
1016
1017static inline unsigned long module_kallsyms_lookup_name(const char *name)
1018{
1019 return 0;
1020}
1021
1022static inline unsigned long find_kallsyms_symbol_value(struct module *mod,
1023 const char *name)
1024{
1025 return 0;
1026}
1027
1028#endif /* CONFIG_MODULES && CONFIG_KALLSYMS */
1029
1030#endif /* _LINUX_MODULE_H */