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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(__KBUILD_MODNAME, \ 255 __PASTE(__, \ 256 __PASTE(type, \ 257 __PASTE(__, name))))) 258 259/* Creates an alias so file2alias.c can find device table. */ 260#define MODULE_DEVICE_TABLE(type, name) \ 261static typeof(name) __mod_device_table(type, name) \ 262 __attribute__ ((used, alias(__stringify(name)))) 263 264/* Version of form [<epoch>:]<version>[-<extra-version>]. 265 * Or for CVS/RCS ID version, everything but the number is stripped. 266 * <epoch>: A (small) unsigned integer which allows you to start versions 267 * anew. If not mentioned, it's zero. eg. "2:1.0" is after 268 * "1:2.0". 269 270 * <version>: The <version> may contain only alphanumerics and the 271 * character `.'. Ordered by numeric sort for numeric parts, 272 * ascii sort for ascii parts (as per RPM or DEB algorithm). 273 274 * <extraversion>: Like <version>, but inserted for local 275 * customizations, eg "rh3" or "rusty1". 276 277 * Using this automatically adds a checksum of the .c files and the 278 * local headers in "srcversion". 279 */ 280 281#if defined(MODULE) || !defined(CONFIG_SYSFS) 282#define MODULE_VERSION(_version) MODULE_INFO(version, _version) 283#else 284#define MODULE_VERSION(_version) \ 285 MODULE_INFO(version, _version); \ 286 static const struct module_version_attribute __modver_attr \ 287 __used __section("__modver") \ 288 __aligned(__alignof__(struct module_version_attribute)) \ 289 = { \ 290 .mattr = { \ 291 .attr = { \ 292 .name = "version", \ 293 .mode = S_IRUGO, \ 294 }, \ 295 .show = __modver_version_show, \ 296 }, \ 297 .module_name = KBUILD_MODNAME, \ 298 .version = _version, \ 299 } 300#endif 301 302/* Optional firmware file (or files) needed by the module 303 * format is simply firmware file name. Multiple firmware 304 * files require multiple MODULE_FIRMWARE() specifiers */ 305#define MODULE_FIRMWARE(_firmware) MODULE_INFO(firmware, _firmware) 306 307#define MODULE_IMPORT_NS(ns) MODULE_INFO(import_ns, ns) 308 309struct notifier_block; 310 311enum module_state { 312 MODULE_STATE_LIVE, /* Normal state. */ 313 MODULE_STATE_COMING, /* Full formed, running module_init. */ 314 MODULE_STATE_GOING, /* Going away. */ 315 MODULE_STATE_UNFORMED, /* Still setting it up. */ 316}; 317 318struct mod_tree_node { 319 struct module *mod; 320 struct latch_tree_node node; 321}; 322 323enum mod_mem_type { 324 MOD_TEXT = 0, 325 MOD_DATA, 326 MOD_RODATA, 327 MOD_RO_AFTER_INIT, 328 MOD_INIT_TEXT, 329 MOD_INIT_DATA, 330 MOD_INIT_RODATA, 331 332 MOD_MEM_NUM_TYPES, 333 MOD_INVALID = -1, 334}; 335 336#define mod_mem_type_is_init(type) \ 337 ((type) == MOD_INIT_TEXT || \ 338 (type) == MOD_INIT_DATA || \ 339 (type) == MOD_INIT_RODATA) 340 341#define mod_mem_type_is_core(type) (!mod_mem_type_is_init(type)) 342 343#define mod_mem_type_is_text(type) \ 344 ((type) == MOD_TEXT || \ 345 (type) == MOD_INIT_TEXT) 346 347#define mod_mem_type_is_data(type) (!mod_mem_type_is_text(type)) 348 349#define mod_mem_type_is_core_data(type) \ 350 (mod_mem_type_is_core(type) && \ 351 mod_mem_type_is_data(type)) 352 353#define for_each_mod_mem_type(type) \ 354 for (enum mod_mem_type (type) = 0; \ 355 (type) < MOD_MEM_NUM_TYPES; (type)++) 356 357#define for_class_mod_mem_type(type, class) \ 358 for_each_mod_mem_type(type) \ 359 if (mod_mem_type_is_##class(type)) 360 361struct module_memory { 362 void *base; 363 bool is_rox; 364 unsigned int size; 365 366#ifdef CONFIG_MODULES_TREE_LOOKUP 367 struct mod_tree_node mtn; 368#endif 369}; 370 371#ifdef CONFIG_MODULES_TREE_LOOKUP 372/* Only touch one cacheline for common rbtree-for-core-layout case. */ 373#define __module_memory_align ____cacheline_aligned 374#else 375#define __module_memory_align 376#endif 377 378struct mod_kallsyms { 379 Elf_Sym *symtab; 380 unsigned int num_symtab; 381 char *strtab; 382 char *typetab; 383}; 384 385#ifdef CONFIG_LIVEPATCH 386/** 387 * struct klp_modinfo - ELF information preserved from the livepatch module 388 * 389 * @hdr: ELF header 390 * @sechdrs: Section header table 391 * @secstrings: String table for the section headers 392 * @symndx: The symbol table section index 393 */ 394struct klp_modinfo { 395 Elf_Ehdr hdr; 396 Elf_Shdr *sechdrs; 397 char *secstrings; 398 unsigned int symndx; 399}; 400#endif 401 402struct module { 403 enum module_state state; 404 405 /* Member of list of modules */ 406 struct list_head list; 407 408 /* Unique handle for this module */ 409 char name[MODULE_NAME_LEN]; 410 411#ifdef CONFIG_STACKTRACE_BUILD_ID 412 /* Module build ID */ 413 unsigned char build_id[BUILD_ID_SIZE_MAX]; 414#endif 415 416 /* Sysfs stuff. */ 417 struct module_kobject mkobj; 418 struct module_attribute *modinfo_attrs; 419 const char *version; 420 const char *srcversion; 421 struct kobject *holders_dir; 422 423 /* Exported symbols */ 424 const struct kernel_symbol *syms; 425 const u32 *crcs; 426 unsigned int num_syms; 427 428#ifdef CONFIG_ARCH_USES_CFI_TRAPS 429 s32 *kcfi_traps; 430 s32 *kcfi_traps_end; 431#endif 432 433 /* Kernel parameters. */ 434#ifdef CONFIG_SYSFS 435 struct mutex param_lock; 436#endif 437 struct kernel_param *kp; 438 unsigned int num_kp; 439 440 /* GPL-only exported symbols. */ 441 unsigned int num_gpl_syms; 442 const struct kernel_symbol *gpl_syms; 443 const u32 *gpl_crcs; 444 bool using_gplonly_symbols; 445 446#ifdef CONFIG_MODULE_SIG 447 /* Signature was verified. */ 448 bool sig_ok; 449#endif 450 451 bool async_probe_requested; 452 453 /* Exception table */ 454 unsigned int num_exentries; 455 struct exception_table_entry *extable; 456 457 /* Startup function. */ 458 int (*init)(void); 459 460 struct module_memory mem[MOD_MEM_NUM_TYPES] __module_memory_align; 461 462 /* Arch-specific module values */ 463 struct mod_arch_specific arch; 464 465 unsigned long taints; /* same bits as kernel:taint_flags */ 466 467#ifdef CONFIG_GENERIC_BUG 468 /* Support for BUG */ 469 unsigned num_bugs; 470 struct list_head bug_list; 471 struct bug_entry *bug_table; 472#endif 473 474#ifdef CONFIG_KALLSYMS 475 /* Protected by RCU and/or module_mutex: use rcu_dereference() */ 476 struct mod_kallsyms __rcu *kallsyms; 477 struct mod_kallsyms core_kallsyms; 478 479 /* Section attributes */ 480 struct module_sect_attrs *sect_attrs; 481 482 /* Notes attributes */ 483 struct module_notes_attrs *notes_attrs; 484#endif 485 486 /* The command line arguments (may be mangled). People like 487 keeping pointers to this stuff */ 488 char *args; 489 490#ifdef CONFIG_SMP 491 /* Per-cpu data. */ 492 void __percpu *percpu; 493 unsigned int percpu_size; 494#endif 495 void *noinstr_text_start; 496 unsigned int noinstr_text_size; 497 498#ifdef CONFIG_TRACEPOINTS 499 unsigned int num_tracepoints; 500 tracepoint_ptr_t *tracepoints_ptrs; 501#endif 502#ifdef CONFIG_TREE_SRCU 503 unsigned int num_srcu_structs; 504 struct srcu_struct **srcu_struct_ptrs; 505#endif 506#ifdef CONFIG_BPF_EVENTS 507 unsigned int num_bpf_raw_events; 508 struct bpf_raw_event_map *bpf_raw_events; 509#endif 510#ifdef CONFIG_DEBUG_INFO_BTF_MODULES 511 unsigned int btf_data_size; 512 unsigned int btf_base_data_size; 513 void *btf_data; 514 void *btf_base_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_DYNAMIC_FTRACE 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_init_suites; 546 struct kunit_suite **kunit_init_suites; 547 int num_kunit_suites; 548 struct kunit_suite **kunit_suites; 549#endif 550 551 552#ifdef CONFIG_LIVEPATCH 553 bool klp; /* Is this a livepatch module? */ 554 bool klp_alive; 555 556 /* ELF information */ 557 struct klp_modinfo *klp_info; 558#endif 559 560#ifdef CONFIG_PRINTK_INDEX 561 unsigned int printk_index_size; 562 struct pi_entry **printk_index_start; 563#endif 564 565#ifdef CONFIG_MODULE_UNLOAD 566 /* What modules depend on me? */ 567 struct list_head source_list; 568 /* What modules do I depend on? */ 569 struct list_head target_list; 570 571 /* Destruction function. */ 572 void (*exit)(void); 573 574 atomic_t refcnt; 575#endif 576 577#ifdef CONFIG_CONSTRUCTORS 578 /* Constructor functions. */ 579 ctor_fn_t *ctors; 580 unsigned int num_ctors; 581#endif 582 583#ifdef CONFIG_FUNCTION_ERROR_INJECTION 584 struct error_injection_entry *ei_funcs; 585 unsigned int num_ei_funcs; 586#endif 587#ifdef CONFIG_DYNAMIC_DEBUG_CORE 588 struct _ddebug_info dyndbg_info; 589#endif 590} ____cacheline_aligned __randomize_layout; 591#ifndef MODULE_ARCH_INIT 592#define MODULE_ARCH_INIT {} 593#endif 594 595#ifdef CONFIG_MODULES 596 597/* Get/put a kernel symbol (calls must be symmetric) */ 598void *__symbol_get(const char *symbol); 599void *__symbol_get_gpl(const char *symbol); 600#define symbol_get(x) ({ \ 601 static const char __notrim[] \ 602 __used __section(".no_trim_symbol") = __stringify(x); \ 603 (typeof(&x))(__symbol_get(__stringify(x))); }) 604 605#ifndef HAVE_ARCH_KALLSYMS_SYMBOL_VALUE 606static inline unsigned long kallsyms_symbol_value(const Elf_Sym *sym) 607{ 608 return sym->st_value; 609} 610#endif 611 612/* FIXME: It'd be nice to isolate modules during init, too, so they 613 aren't used before they (may) fail. But presently too much code 614 (IDE & SCSI) require entry into the module during init.*/ 615static inline bool module_is_live(struct module *mod) 616{ 617 return mod->state != MODULE_STATE_GOING; 618} 619 620static inline bool module_is_coming(struct module *mod) 621{ 622 return mod->state == MODULE_STATE_COMING; 623} 624 625struct module *__module_text_address(unsigned long addr); 626struct module *__module_address(unsigned long addr); 627bool is_module_address(unsigned long addr); 628bool __is_module_percpu_address(unsigned long addr, unsigned long *can_addr); 629bool is_module_percpu_address(unsigned long addr); 630bool is_module_text_address(unsigned long addr); 631 632static inline bool within_module_mem_type(unsigned long addr, 633 const struct module *mod, 634 enum mod_mem_type type) 635{ 636 unsigned long base, size; 637 638 base = (unsigned long)mod->mem[type].base; 639 size = mod->mem[type].size; 640 return addr - base < size; 641} 642 643static inline bool within_module_core(unsigned long addr, 644 const struct module *mod) 645{ 646 for_class_mod_mem_type(type, core) { 647 if (within_module_mem_type(addr, mod, type)) 648 return true; 649 } 650 return false; 651} 652 653static inline bool within_module_init(unsigned long addr, 654 const struct module *mod) 655{ 656 for_class_mod_mem_type(type, init) { 657 if (within_module_mem_type(addr, mod, type)) 658 return true; 659 } 660 return false; 661} 662 663static inline bool within_module(unsigned long addr, const struct module *mod) 664{ 665 return within_module_init(addr, mod) || within_module_core(addr, mod); 666} 667 668/* Search for module by name: must be in a RCU critical section. */ 669struct module *find_module(const char *name); 670 671extern void __noreturn __module_put_and_kthread_exit(struct module *mod, 672 long code); 673#define module_put_and_kthread_exit(code) __module_put_and_kthread_exit(THIS_MODULE, code) 674 675#ifdef CONFIG_MODULE_UNLOAD 676int module_refcount(struct module *mod); 677void __symbol_put(const char *symbol); 678#define symbol_put(x) __symbol_put(__stringify(x)) 679void symbol_put_addr(void *addr); 680 681/* Sometimes we know we already have a refcount, and it's easier not 682 to handle the error case (which only happens with rmmod --wait). */ 683extern void __module_get(struct module *module); 684 685/** 686 * try_module_get() - take module refcount unless module is being removed 687 * @module: the module we should check for 688 * 689 * Only try to get a module reference count if the module is not being removed. 690 * This call will fail if the module is in the process of being removed. 691 * 692 * Care must also be taken to ensure the module exists and is alive prior to 693 * usage of this call. This can be gauranteed through two means: 694 * 695 * 1) Direct protection: you know an earlier caller must have increased the 696 * module reference through __module_get(). This can typically be achieved 697 * by having another entity other than the module itself increment the 698 * module reference count. 699 * 700 * 2) Implied protection: there is an implied protection against module 701 * removal. An example of this is the implied protection used by kernfs / 702 * sysfs. The sysfs store / read file operations are guaranteed to exist 703 * through the use of kernfs's active reference (see kernfs_active()) and a 704 * sysfs / kernfs file removal cannot happen unless the same file is not 705 * active. Therefore, if a sysfs file is being read or written to the module 706 * which created it must still exist. It is therefore safe to use 707 * try_module_get() on module sysfs store / read ops. 708 * 709 * One of the real values to try_module_get() is the module_is_live() check 710 * which ensures that the caller of try_module_get() can yield to userspace 711 * module removal requests and gracefully fail if the module is on its way out. 712 * 713 * Returns true if the reference count was successfully incremented. 714 */ 715extern bool try_module_get(struct module *module); 716 717/** 718 * module_put() - release a reference count to a module 719 * @module: the module we should release a reference count for 720 * 721 * If you successfully bump a reference count to a module with try_module_get(), 722 * when you are finished you must call module_put() to release that reference 723 * count. 724 */ 725extern void module_put(struct module *module); 726 727#else /*!CONFIG_MODULE_UNLOAD*/ 728static inline bool try_module_get(struct module *module) 729{ 730 return !module || module_is_live(module); 731} 732static inline void module_put(struct module *module) 733{ 734} 735static inline void __module_get(struct module *module) 736{ 737} 738#define symbol_put(x) do { } while (0) 739#define symbol_put_addr(p) do { } while (0) 740 741#endif /* CONFIG_MODULE_UNLOAD */ 742 743/* This is a #define so the string doesn't get put in every .o file */ 744#define module_name(mod) \ 745({ \ 746 struct module *__mod = (mod); \ 747 __mod ? __mod->name : "kernel"; \ 748}) 749 750/* Dereference module function descriptor */ 751void *dereference_module_function_descriptor(struct module *mod, void *ptr); 752 753int register_module_notifier(struct notifier_block *nb); 754int unregister_module_notifier(struct notifier_block *nb); 755 756extern void print_modules(void); 757 758static inline bool module_requested_async_probing(struct module *module) 759{ 760 return module && module->async_probe_requested; 761} 762 763static inline bool is_livepatch_module(struct module *mod) 764{ 765#ifdef CONFIG_LIVEPATCH 766 return mod->klp; 767#else 768 return false; 769#endif 770} 771 772void set_module_sig_enforced(void); 773 774void module_for_each_mod(int(*func)(struct module *mod, void *data), void *data); 775 776#else /* !CONFIG_MODULES... */ 777 778static inline struct module *__module_address(unsigned long addr) 779{ 780 return NULL; 781} 782 783static inline struct module *__module_text_address(unsigned long addr) 784{ 785 return NULL; 786} 787 788static inline bool is_module_address(unsigned long addr) 789{ 790 return false; 791} 792 793static inline bool is_module_percpu_address(unsigned long addr) 794{ 795 return false; 796} 797 798static inline bool __is_module_percpu_address(unsigned long addr, unsigned long *can_addr) 799{ 800 return false; 801} 802 803static inline bool is_module_text_address(unsigned long addr) 804{ 805 return false; 806} 807 808static inline bool within_module_core(unsigned long addr, 809 const struct module *mod) 810{ 811 return false; 812} 813 814static inline bool within_module_init(unsigned long addr, 815 const struct module *mod) 816{ 817 return false; 818} 819 820static inline bool within_module(unsigned long addr, const struct module *mod) 821{ 822 return false; 823} 824 825/* Get/put a kernel symbol (calls should be symmetric) */ 826#define symbol_get(x) ({ extern typeof(x) x __attribute__((weak,visibility("hidden"))); &(x); }) 827#define symbol_put(x) do { } while (0) 828#define symbol_put_addr(x) do { } while (0) 829 830static inline void __module_get(struct module *module) 831{ 832} 833 834static inline bool try_module_get(struct module *module) 835{ 836 return true; 837} 838 839static inline void module_put(struct module *module) 840{ 841} 842 843#define module_name(mod) "kernel" 844 845static inline int register_module_notifier(struct notifier_block *nb) 846{ 847 /* no events will happen anyway, so this can always succeed */ 848 return 0; 849} 850 851static inline int unregister_module_notifier(struct notifier_block *nb) 852{ 853 return 0; 854} 855 856#define module_put_and_kthread_exit(code) kthread_exit(code) 857 858static inline void print_modules(void) 859{ 860} 861 862static inline bool module_requested_async_probing(struct module *module) 863{ 864 return false; 865} 866 867 868static inline void set_module_sig_enforced(void) 869{ 870} 871 872/* Dereference module function descriptor */ 873static inline 874void *dereference_module_function_descriptor(struct module *mod, void *ptr) 875{ 876 return ptr; 877} 878 879static inline bool module_is_coming(struct module *mod) 880{ 881 return false; 882} 883 884static inline void module_for_each_mod(int(*func)(struct module *mod, void *data), void *data) 885{ 886} 887#endif /* CONFIG_MODULES */ 888 889#ifdef CONFIG_SYSFS 890extern struct kset *module_kset; 891extern const struct kobj_type module_ktype; 892#endif /* CONFIG_SYSFS */ 893 894#define symbol_request(x) try_then_request_module(symbol_get(x), "symbol:" #x) 895 896/* BELOW HERE ALL THESE ARE OBSOLETE AND WILL VANISH */ 897 898#define __MODULE_STRING(x) __stringify(x) 899 900#ifdef CONFIG_GENERIC_BUG 901void module_bug_finalize(const Elf_Ehdr *, const Elf_Shdr *, 902 struct module *); 903void module_bug_cleanup(struct module *); 904 905#else /* !CONFIG_GENERIC_BUG */ 906 907static inline void module_bug_finalize(const Elf_Ehdr *hdr, 908 const Elf_Shdr *sechdrs, 909 struct module *mod) 910{ 911} 912static inline void module_bug_cleanup(struct module *mod) {} 913#endif /* CONFIG_GENERIC_BUG */ 914 915#ifdef CONFIG_MITIGATION_RETPOLINE 916extern bool retpoline_module_ok(bool has_retpoline); 917#else 918static inline bool retpoline_module_ok(bool has_retpoline) 919{ 920 return true; 921} 922#endif 923 924#ifdef CONFIG_MODULE_SIG 925bool is_module_sig_enforced(void); 926 927static inline bool module_sig_ok(struct module *module) 928{ 929 return module->sig_ok; 930} 931#else /* !CONFIG_MODULE_SIG */ 932static inline bool is_module_sig_enforced(void) 933{ 934 return false; 935} 936 937static inline bool module_sig_ok(struct module *module) 938{ 939 return true; 940} 941#endif /* CONFIG_MODULE_SIG */ 942 943#if defined(CONFIG_MODULES) && defined(CONFIG_KALLSYMS) 944int module_kallsyms_on_each_symbol(const char *modname, 945 int (*fn)(void *, const char *, unsigned long), 946 void *data); 947 948/* For kallsyms to ask for address resolution. namebuf should be at 949 * least KSYM_NAME_LEN long: a pointer to namebuf is returned if 950 * found, otherwise NULL. 951 */ 952int module_address_lookup(unsigned long addr, 953 unsigned long *symbolsize, 954 unsigned long *offset, 955 char **modname, const unsigned char **modbuildid, 956 char *namebuf); 957int lookup_module_symbol_name(unsigned long addr, char *symname); 958int lookup_module_symbol_attrs(unsigned long addr, 959 unsigned long *size, 960 unsigned long *offset, 961 char *modname, 962 char *name); 963 964/* Returns 0 and fills in value, defined and namebuf, or -ERANGE if 965 * symnum out of range. 966 */ 967int module_get_kallsym(unsigned int symnum, unsigned long *value, char *type, 968 char *name, char *module_name, int *exported); 969 970/* Look for this name: can be of form module:name. */ 971unsigned long module_kallsyms_lookup_name(const char *name); 972 973unsigned long find_kallsyms_symbol_value(struct module *mod, const char *name); 974 975#else /* CONFIG_MODULES && CONFIG_KALLSYMS */ 976 977static inline int module_kallsyms_on_each_symbol(const char *modname, 978 int (*fn)(void *, const char *, unsigned long), 979 void *data) 980{ 981 return -EOPNOTSUPP; 982} 983 984/* For kallsyms to ask for address resolution. NULL means not found. */ 985static inline int module_address_lookup(unsigned long addr, 986 unsigned long *symbolsize, 987 unsigned long *offset, 988 char **modname, 989 const unsigned char **modbuildid, 990 char *namebuf) 991{ 992 return 0; 993} 994 995static inline int lookup_module_symbol_name(unsigned long addr, char *symname) 996{ 997 return -ERANGE; 998} 999 1000static inline int module_get_kallsym(unsigned int symnum, unsigned long *value, 1001 char *type, char *name, 1002 char *module_name, int *exported) 1003{ 1004 return -ERANGE; 1005} 1006 1007static inline unsigned long module_kallsyms_lookup_name(const char *name) 1008{ 1009 return 0; 1010} 1011 1012static inline unsigned long find_kallsyms_symbol_value(struct module *mod, 1013 const char *name) 1014{ 1015 return 0; 1016} 1017 1018#endif /* CONFIG_MODULES && CONFIG_KALLSYMS */ 1019 1020/* Define __free(module_put) macro for struct module *. */ 1021DEFINE_FREE(module_put, struct module *, if (_T) module_put(_T)) 1022 1023#endif /* _LINUX_MODULE_H */