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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 */