1 /* SPDX-License-Identifier: GPL-2.0-only */ 2 /* 3 * Dynamic loading of modules into the kernel. 4 * 5 * Rewritten by Richard Henderson <[email protected]> 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 /* Generic info of form tag = "info" */ 166 #define MODULE_INFO(tag, info) __MODULE_INFO(tag, tag, info) 167 168 /* For userspace: you can also call me... */ 169 #define MODULE_ALIAS(_alias) MODULE_INFO(alias, _alias) 170 171 /* Soft module dependencies. See man modprobe.d for details. 172 * Example: MODULE_SOFTDEP("pre: module-foo module-bar post: module-baz") 173 */ 174 #define MODULE_SOFTDEP(_softdep) MODULE_INFO(softdep, _softdep) 175 176 /* 177 * MODULE_FILE is used for generating modules.builtin 178 * So, make it no-op when this is being built as a module 179 */ 180 #ifdef MODULE 181 #define MODULE_FILE 182 #else 183 #define MODULE_FILE MODULE_INFO(file, KBUILD_MODFILE); 184 #endif 185 186 /* 187 * The following license idents are currently accepted as indicating free 188 * software modules 189 * 190 * "GPL" [GNU Public License v2] 191 * "GPL v2" [GNU Public License v2] 192 * "GPL and additional rights" [GNU Public License v2 rights and more] 193 * "Dual BSD/GPL" [GNU Public License v2 194 * or BSD license choice] 195 * "Dual MIT/GPL" [GNU Public License v2 196 * or MIT license choice] 197 * "Dual MPL/GPL" [GNU Public License v2 198 * or Mozilla license choice] 199 * 200 * The following other idents are available 201 * 202 * "Proprietary" [Non free products] 203 * 204 * Both "GPL v2" and "GPL" (the latter also in dual licensed strings) are 205 * merely stating that the module is licensed under the GPL v2, but are not 206 * telling whether "GPL v2 only" or "GPL v2 or later". The reason why there 207 * are two variants is a historic and failed attempt to convey more 208 * information in the MODULE_LICENSE string. For module loading the 209 * "only/or later" distinction is completely irrelevant and does neither 210 * replace the proper license identifiers in the corresponding source file 211 * nor amends them in any way. The sole purpose is to make the 212 * 'Proprietary' flagging work and to refuse to bind symbols which are 213 * exported with EXPORT_SYMBOL_GPL when a non free module is loaded. 214 * 215 * In the same way "BSD" is not a clear license information. It merely 216 * states, that the module is licensed under one of the compatible BSD 217 * license variants. The detailed and correct license information is again 218 * to be found in the corresponding source files. 219 * 220 * There are dual licensed components, but when running with Linux it is the 221 * GPL that is relevant so this is a non issue. Similarly LGPL linked with GPL 222 * is a GPL combined work. 223 * 224 * This exists for several reasons 225 * 1. So modinfo can show license info for users wanting to vet their setup 226 * is free 227 * 2. So the community can ignore bug reports including proprietary modules 228 * 3. So vendors can do likewise based on their own policies 229 */ 230 #define MODULE_LICENSE(_license) MODULE_FILE MODULE_INFO(license, _license) 231 232 /* 233 * Author(s), use "Name <email>" or just "Name", for multiple 234 * authors use multiple MODULE_AUTHOR() statements/lines. 235 */ 236 #define MODULE_AUTHOR(_author) MODULE_INFO(author, _author) 237 238 /* What your module does. */ 239 #define MODULE_DESCRIPTION(_description) MODULE_INFO(description, _description) 240 241 #ifdef MODULE 242 /* Creates an alias so file2alias.c can find device table. */ 243 #define MODULE_DEVICE_TABLE(type, name) \ 244 extern typeof(name) __mod_##type##__##name##_device_table \ 245 __attribute__ ((unused, alias(__stringify(name)))) 246 #else /* !MODULE */ 247 #define MODULE_DEVICE_TABLE(type, name) 248 #endif 249 250 /* Version of form [<epoch>:]<version>[-<extra-version>]. 251 * Or for CVS/RCS ID version, everything but the number is stripped. 252 * <epoch>: A (small) unsigned integer which allows you to start versions 253 * anew. If not mentioned, it's zero. eg. "2:1.0" is after 254 * "1:2.0". 255 256 * <version>: The <version> may contain only alphanumerics and the 257 * character `.'. Ordered by numeric sort for numeric parts, 258 * ascii sort for ascii parts (as per RPM or DEB algorithm). 259 260 * <extraversion>: Like <version>, but inserted for local 261 * customizations, eg "rh3" or "rusty1". 262 263 * Using this automatically adds a checksum of the .c files and the 264 * local headers in "srcversion". 265 */ 266 267 #if defined(MODULE) || !defined(CONFIG_SYSFS) 268 #define MODULE_VERSION(_version) MODULE_INFO(version, _version) 269 #else 270 #define MODULE_VERSION(_version) \ 271 MODULE_INFO(version, _version); \ 272 static struct module_version_attribute __modver_attr \ 273 __used __section("__modver") \ 274 __aligned(__alignof__(struct module_version_attribute)) \ 275 = { \ 276 .mattr = { \ 277 .attr = { \ 278 .name = "version", \ 279 .mode = S_IRUGO, \ 280 }, \ 281 .show = __modver_version_show, \ 282 }, \ 283 .module_name = KBUILD_MODNAME, \ 284 .version = _version, \ 285 } 286 #endif 287 288 /* Optional firmware file (or files) needed by the module 289 * format is simply firmware file name. Multiple firmware 290 * files require multiple MODULE_FIRMWARE() specifiers */ 291 #define MODULE_FIRMWARE(_firmware) MODULE_INFO(firmware, _firmware) 292 293 #define MODULE_IMPORT_NS(ns) MODULE_INFO(import_ns, __stringify(ns)) 294 295 struct notifier_block; 296 297 #ifdef CONFIG_MODULES 298 299 extern int modules_disabled; /* for sysctl */ 300 /* Get/put a kernel symbol (calls must be symmetric) */ 301 void *__symbol_get(const char *symbol); 302 void *__symbol_get_gpl(const char *symbol); 303 #define symbol_get(x) ((typeof(&x))(__symbol_get(__stringify(x)))) 304 305 /* modules using other modules: kdb wants to see this. */ 306 struct module_use { 307 struct list_head source_list; 308 struct list_head target_list; 309 struct module *source, *target; 310 }; 311 312 enum 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 }; 318 319 struct mod_tree_node { 320 struct module *mod; 321 struct latch_tree_node node; 322 }; 323 324 enum 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)) 361 362 struct module_memory { 363 void *base; 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 377 378 struct 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 */ 394 struct klp_modinfo { 395 Elf_Ehdr hdr; 396 Elf_Shdr *sechdrs; 397 char *secstrings; 398 unsigned int symndx; 399 }; 400 #endif 401 402 struct 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 s32 *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 s32 *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 void *btf_data; 513 #endif 514 #ifdef CONFIG_JUMP_LABEL 515 struct jump_entry *jump_entries; 516 unsigned int num_jump_entries; 517 #endif 518 #ifdef CONFIG_TRACING 519 unsigned int num_trace_bprintk_fmt; 520 const char **trace_bprintk_fmt_start; 521 #endif 522 #ifdef CONFIG_EVENT_TRACING 523 struct trace_event_call **trace_events; 524 unsigned int num_trace_events; 525 struct trace_eval_map **trace_evals; 526 unsigned int num_trace_evals; 527 #endif 528 #ifdef CONFIG_FTRACE_MCOUNT_RECORD 529 unsigned int num_ftrace_callsites; 530 unsigned long *ftrace_callsites; 531 #endif 532 #ifdef CONFIG_KPROBES 533 void *kprobes_text_start; 534 unsigned int kprobes_text_size; 535 unsigned long *kprobe_blacklist; 536 unsigned int num_kprobe_blacklist; 537 #endif 538 #ifdef CONFIG_HAVE_STATIC_CALL_INLINE 539 int num_static_call_sites; 540 struct static_call_site *static_call_sites; 541 #endif 542 #if IS_ENABLED(CONFIG_KUNIT) 543 int num_kunit_init_suites; 544 struct kunit_suite **kunit_init_suites; 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_CONSTRUCTORS 576 /* Constructor functions. */ 577 ctor_fn_t *ctors; 578 unsigned int num_ctors; 579 #endif 580 581 #ifdef CONFIG_FUNCTION_ERROR_INJECTION 582 struct error_injection_entry *ei_funcs; 583 unsigned int num_ei_funcs; 584 #endif 585 #ifdef CONFIG_DYNAMIC_DEBUG_CORE 586 struct _ddebug_info dyndbg_info; 587 #endif 588 } ____cacheline_aligned __randomize_layout; 589 #ifndef MODULE_ARCH_INIT 590 #define MODULE_ARCH_INIT {} 591 #endif 592 593 #ifndef HAVE_ARCH_KALLSYMS_SYMBOL_VALUE 594 static inline unsigned long kallsyms_symbol_value(const Elf_Sym *sym) 595 { 596 return sym->st_value; 597 } 598 #endif 599 600 /* FIXME: It'd be nice to isolate modules during init, too, so they 601 aren't used before they (may) fail. But presently too much code 602 (IDE & SCSI) require entry into the module during init.*/ 603 static inline bool module_is_live(struct module *mod) 604 { 605 return mod->state != MODULE_STATE_GOING; 606 } 607 608 static inline bool module_is_coming(struct module *mod) 609 { 610 return mod->state == MODULE_STATE_COMING; 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); 619 620 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 } 630 631 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 } 640 641 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 } 650 651 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 in the process of 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*/ 716 static inline bool try_module_get(struct module *module) 717 { 718 return !module || module_is_live(module); 719 } 720 static inline void module_put(struct module *module) 721 { 722 } 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); 745 746 static inline bool module_requested_async_probing(struct module *module) 747 { 748 return module && module->async_probe_requested; 749 } 750 751 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... */ 763 764 static inline struct module *__module_address(unsigned long addr) 765 { 766 return NULL; 767 } 768 769 static inline struct module *__module_text_address(unsigned long addr) 770 { 771 return NULL; 772 } 773 774 static inline bool is_module_address(unsigned long addr) 775 { 776 return false; 777 } 778 779 static inline bool is_module_percpu_address(unsigned long addr) 780 { 781 return false; 782 } 783 784 static inline bool __is_module_percpu_address(unsigned long addr, unsigned long *can_addr) 785 { 786 return false; 787 } 788 789 static inline bool is_module_text_address(unsigned long addr) 790 { 791 return false; 792 } 793 794 static inline bool within_module_core(unsigned long addr, 795 const struct module *mod) 796 { 797 return false; 798 } 799 800 static inline bool within_module_init(unsigned long addr, 801 const struct module *mod) 802 { 803 return false; 804 } 805 806 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) 815 816 static inline void __module_get(struct module *module) 817 { 818 } 819 820 static inline bool try_module_get(struct module *module) 821 { 822 return true; 823 } 824 825 static inline void module_put(struct module *module) 826 { 827 } 828 829 #define module_name(mod) "kernel" 830 831 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 } 836 837 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) 843 844 static inline void print_modules(void) 845 { 846 } 847 848 static inline bool module_requested_async_probing(struct module *module) 849 { 850 return false; 851 } 852 853 854 static inline void set_module_sig_enforced(void) 855 { 856 } 857 858 /* Dereference module function descriptor */ 859 static inline 860 void *dereference_module_function_descriptor(struct module *mod, void *ptr) 861 { 862 return ptr; 863 } 864 865 static inline bool module_is_coming(struct module *mod) 866 { 867 return false; 868 } 869 #endif /* CONFIG_MODULES */ 870 871 #ifdef CONFIG_SYSFS 872 extern struct kset *module_kset; 873 extern const struct kobj_type module_ktype; 874 #endif /* CONFIG_SYSFS */ 875 876 #define symbol_request(x) try_then_request_module(symbol_get(x), "symbol:" #x) 877 878 /* BELOW HERE ALL THESE ARE OBSOLETE AND WILL VANISH */ 879 880 #define __MODULE_STRING(x) __stringify(x) 881 882 #ifdef CONFIG_GENERIC_BUG 883 void module_bug_finalize(const Elf_Ehdr *, const Elf_Shdr *, 884 struct module *); 885 void module_bug_cleanup(struct module *); 886 887 #else /* !CONFIG_GENERIC_BUG */ 888 889 static inline void module_bug_finalize(const Elf_Ehdr *hdr, 890 const Elf_Shdr *sechdrs, 891 struct module *mod) 892 { 893 } 894 static inline void module_bug_cleanup(struct module *mod) {} 895 #endif /* CONFIG_GENERIC_BUG */ 896 897 #ifdef CONFIG_MITIGATION_RETPOLINE 898 extern bool retpoline_module_ok(bool has_retpoline); 899 #else 900 static inline bool retpoline_module_ok(bool has_retpoline) 901 { 902 return true; 903 } 904 #endif 905 906 #ifdef CONFIG_MODULE_SIG 907 bool is_module_sig_enforced(void); 908 909 static inline bool module_sig_ok(struct module *module) 910 { 911 return module->sig_ok; 912 } 913 #else /* !CONFIG_MODULE_SIG */ 914 static inline bool is_module_sig_enforced(void) 915 { 916 return false; 917 } 918 919 static inline bool module_sig_ok(struct module *module) 920 { 921 return true; 922 } 923 #endif /* CONFIG_MODULE_SIG */ 924 925 #if defined(CONFIG_MODULES) && defined(CONFIG_KALLSYMS) 926 int module_kallsyms_on_each_symbol(const char *modname, 927 int (*fn)(void *, const char *, unsigned long), 928 void *data); 929 930 /* For kallsyms to ask for address resolution. namebuf should be at 931 * least KSYM_NAME_LEN long: a pointer to namebuf is returned if 932 * found, otherwise NULL. 933 */ 934 const char *module_address_lookup(unsigned long addr, 935 unsigned long *symbolsize, 936 unsigned long *offset, 937 char **modname, const unsigned char **modbuildid, 938 char *namebuf); 939 int lookup_module_symbol_name(unsigned long addr, char *symname); 940 int lookup_module_symbol_attrs(unsigned long addr, 941 unsigned long *size, 942 unsigned long *offset, 943 char *modname, 944 char *name); 945 946 /* Returns 0 and fills in value, defined and namebuf, or -ERANGE if 947 * symnum out of range. 948 */ 949 int module_get_kallsym(unsigned int symnum, unsigned long *value, char *type, 950 char *name, char *module_name, int *exported); 951 952 /* Look for this name: can be of form module:name. */ 953 unsigned long module_kallsyms_lookup_name(const char *name); 954 955 unsigned long find_kallsyms_symbol_value(struct module *mod, const char *name); 956 957 #else /* CONFIG_MODULES && CONFIG_KALLSYMS */ 958 959 static inline int module_kallsyms_on_each_symbol(const char *modname, 960 int (*fn)(void *, const char *, unsigned long), 961 void *data) 962 { 963 return -EOPNOTSUPP; 964 } 965 966 /* For kallsyms to ask for address resolution. NULL means not found. */ 967 static inline const char *module_address_lookup(unsigned long addr, 968 unsigned long *symbolsize, 969 unsigned long *offset, 970 char **modname, 971 const unsigned char **modbuildid, 972 char *namebuf) 973 { 974 return NULL; 975 } 976 977 static inline int lookup_module_symbol_name(unsigned long addr, char *symname) 978 { 979 return -ERANGE; 980 } 981 982 static inline int module_get_kallsym(unsigned int symnum, unsigned long *value, 983 char *type, char *name, 984 char *module_name, int *exported) 985 { 986 return -ERANGE; 987 } 988 989 static inline unsigned long module_kallsyms_lookup_name(const char *name) 990 { 991 return 0; 992 } 993 994 static inline unsigned long find_kallsyms_symbol_value(struct module *mod, 995 const char *name) 996 { 997 return 0; 998 } 999 1000 #endif /* CONFIG_MODULES && CONFIG_KALLSYMS */ 1001 1002 #endif /* _LINUX_MODULE_H */ 1003