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