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_suites; 544 struct kunit_suite **kunit_suites; 545 #endif 546 547 548 #ifdef CONFIG_LIVEPATCH 549 bool klp; /* Is this a livepatch module? */ 550 bool klp_alive; 551 552 /* ELF information */ 553 struct klp_modinfo *klp_info; 554 #endif 555 556 #ifdef CONFIG_PRINTK_INDEX 557 unsigned int printk_index_size; 558 struct pi_entry **printk_index_start; 559 #endif 560 561 #ifdef CONFIG_MODULE_UNLOAD 562 /* What modules depend on me? */ 563 struct list_head source_list; 564 /* What modules do I depend on? */ 565 struct list_head target_list; 566 567 /* Destruction function. */ 568 void (*exit)(void); 569 570 atomic_t refcnt; 571 #endif 572 573 #ifdef CONFIG_CONSTRUCTORS 574 /* Constructor functions. */ 575 ctor_fn_t *ctors; 576 unsigned int num_ctors; 577 #endif 578 579 #ifdef CONFIG_FUNCTION_ERROR_INJECTION 580 struct error_injection_entry *ei_funcs; 581 unsigned int num_ei_funcs; 582 #endif 583 #ifdef CONFIG_DYNAMIC_DEBUG_CORE 584 struct _ddebug_info dyndbg_info; 585 #endif 586 } ____cacheline_aligned __randomize_layout; 587 #ifndef MODULE_ARCH_INIT 588 #define MODULE_ARCH_INIT {} 589 #endif 590 591 #ifndef HAVE_ARCH_KALLSYMS_SYMBOL_VALUE 592 static inline unsigned long kallsyms_symbol_value(const Elf_Sym *sym) 593 { 594 return sym->st_value; 595 } 596 #endif 597 598 /* FIXME: It'd be nice to isolate modules during init, too, so they 599 aren't used before they (may) fail. But presently too much code 600 (IDE & SCSI) require entry into the module during init.*/ 601 static inline bool module_is_live(struct module *mod) 602 { 603 return mod->state != MODULE_STATE_GOING; 604 } 605 606 struct module *__module_text_address(unsigned long addr); 607 struct module *__module_address(unsigned long addr); 608 bool is_module_address(unsigned long addr); 609 bool __is_module_percpu_address(unsigned long addr, unsigned long *can_addr); 610 bool is_module_percpu_address(unsigned long addr); 611 bool is_module_text_address(unsigned long addr); 612 613 static inline bool within_module_mem_type(unsigned long addr, 614 const struct module *mod, 615 enum mod_mem_type type) 616 { 617 unsigned long base, size; 618 619 base = (unsigned long)mod->mem[type].base; 620 size = mod->mem[type].size; 621 return addr - base < size; 622 } 623 624 static inline bool within_module_core(unsigned long addr, 625 const struct module *mod) 626 { 627 for_class_mod_mem_type(type, core) { 628 if (within_module_mem_type(addr, mod, type)) 629 return true; 630 } 631 return false; 632 } 633 634 static inline bool within_module_init(unsigned long addr, 635 const struct module *mod) 636 { 637 for_class_mod_mem_type(type, init) { 638 if (within_module_mem_type(addr, mod, type)) 639 return true; 640 } 641 return false; 642 } 643 644 static inline bool within_module(unsigned long addr, const struct module *mod) 645 { 646 return within_module_init(addr, mod) || within_module_core(addr, mod); 647 } 648 649 /* Search for module by name: must be in a RCU-sched critical section. */ 650 struct module *find_module(const char *name); 651 652 extern void __noreturn __module_put_and_kthread_exit(struct module *mod, 653 long code); 654 #define module_put_and_kthread_exit(code) __module_put_and_kthread_exit(THIS_MODULE, code) 655 656 #ifdef CONFIG_MODULE_UNLOAD 657 int module_refcount(struct module *mod); 658 void __symbol_put(const char *symbol); 659 #define symbol_put(x) __symbol_put(__stringify(x)) 660 void symbol_put_addr(void *addr); 661 662 /* Sometimes we know we already have a refcount, and it's easier not 663 to handle the error case (which only happens with rmmod --wait). */ 664 extern void __module_get(struct module *module); 665 666 /** 667 * try_module_get() - take module refcount unless module is being removed 668 * @module: the module we should check for 669 * 670 * Only try to get a module reference count if the module is not being removed. 671 * This call will fail if the module is already being removed. 672 * 673 * Care must also be taken to ensure the module exists and is alive prior to 674 * usage of this call. This can be gauranteed through two means: 675 * 676 * 1) Direct protection: you know an earlier caller must have increased the 677 * module reference through __module_get(). This can typically be achieved 678 * by having another entity other than the module itself increment the 679 * module reference count. 680 * 681 * 2) Implied protection: there is an implied protection against module 682 * removal. An example of this is the implied protection used by kernfs / 683 * sysfs. The sysfs store / read file operations are guaranteed to exist 684 * through the use of kernfs's active reference (see kernfs_active()) and a 685 * sysfs / kernfs file removal cannot happen unless the same file is not 686 * active. Therefore, if a sysfs file is being read or written to the module 687 * which created it must still exist. It is therefore safe to use 688 * try_module_get() on module sysfs store / read ops. 689 * 690 * One of the real values to try_module_get() is the module_is_live() check 691 * which ensures that the caller of try_module_get() can yield to userspace 692 * module removal requests and gracefully fail if the module is on its way out. 693 * 694 * Returns true if the reference count was successfully incremented. 695 */ 696 extern bool try_module_get(struct module *module); 697 698 /** 699 * module_put() - release a reference count to a module 700 * @module: the module we should release a reference count for 701 * 702 * If you successfully bump a reference count to a module with try_module_get(), 703 * when you are finished you must call module_put() to release that reference 704 * count. 705 */ 706 extern void module_put(struct module *module); 707 708 #else /*!CONFIG_MODULE_UNLOAD*/ 709 static inline bool try_module_get(struct module *module) 710 { 711 return !module || module_is_live(module); 712 } 713 static inline void module_put(struct module *module) 714 { 715 } 716 static inline void __module_get(struct module *module) 717 { 718 } 719 #define symbol_put(x) do { } while (0) 720 #define symbol_put_addr(p) do { } while (0) 721 722 #endif /* CONFIG_MODULE_UNLOAD */ 723 724 /* This is a #define so the string doesn't get put in every .o file */ 725 #define module_name(mod) \ 726 ({ \ 727 struct module *__mod = (mod); \ 728 __mod ? __mod->name : "kernel"; \ 729 }) 730 731 /* Dereference module function descriptor */ 732 void *dereference_module_function_descriptor(struct module *mod, void *ptr); 733 734 int register_module_notifier(struct notifier_block *nb); 735 int unregister_module_notifier(struct notifier_block *nb); 736 737 extern void print_modules(void); 738 739 static inline bool module_requested_async_probing(struct module *module) 740 { 741 return module && module->async_probe_requested; 742 } 743 744 static inline bool is_livepatch_module(struct module *mod) 745 { 746 #ifdef CONFIG_LIVEPATCH 747 return mod->klp; 748 #else 749 return false; 750 #endif 751 } 752 753 void set_module_sig_enforced(void); 754 755 #else /* !CONFIG_MODULES... */ 756 757 static inline struct module *__module_address(unsigned long addr) 758 { 759 return NULL; 760 } 761 762 static inline struct module *__module_text_address(unsigned long addr) 763 { 764 return NULL; 765 } 766 767 static inline bool is_module_address(unsigned long addr) 768 { 769 return false; 770 } 771 772 static inline bool is_module_percpu_address(unsigned long addr) 773 { 774 return false; 775 } 776 777 static inline bool __is_module_percpu_address(unsigned long addr, unsigned long *can_addr) 778 { 779 return false; 780 } 781 782 static inline bool is_module_text_address(unsigned long addr) 783 { 784 return false; 785 } 786 787 static inline bool within_module_core(unsigned long addr, 788 const struct module *mod) 789 { 790 return false; 791 } 792 793 static inline bool within_module_init(unsigned long addr, 794 const struct module *mod) 795 { 796 return false; 797 } 798 799 static inline bool within_module(unsigned long addr, const struct module *mod) 800 { 801 return false; 802 } 803 804 /* Get/put a kernel symbol (calls should be symmetric) */ 805 #define symbol_get(x) ({ extern typeof(x) x __attribute__((weak,visibility("hidden"))); &(x); }) 806 #define symbol_put(x) do { } while (0) 807 #define symbol_put_addr(x) do { } while (0) 808 809 static inline void __module_get(struct module *module) 810 { 811 } 812 813 static inline bool try_module_get(struct module *module) 814 { 815 return true; 816 } 817 818 static inline void module_put(struct module *module) 819 { 820 } 821 822 #define module_name(mod) "kernel" 823 824 static inline int register_module_notifier(struct notifier_block *nb) 825 { 826 /* no events will happen anyway, so this can always succeed */ 827 return 0; 828 } 829 830 static inline int unregister_module_notifier(struct notifier_block *nb) 831 { 832 return 0; 833 } 834 835 #define module_put_and_kthread_exit(code) kthread_exit(code) 836 837 static inline void print_modules(void) 838 { 839 } 840 841 static inline bool module_requested_async_probing(struct module *module) 842 { 843 return false; 844 } 845 846 847 static inline void set_module_sig_enforced(void) 848 { 849 } 850 851 /* Dereference module function descriptor */ 852 static inline 853 void *dereference_module_function_descriptor(struct module *mod, void *ptr) 854 { 855 return ptr; 856 } 857 858 #endif /* CONFIG_MODULES */ 859 860 #ifdef CONFIG_SYSFS 861 extern struct kset *module_kset; 862 extern const struct kobj_type module_ktype; 863 #endif /* CONFIG_SYSFS */ 864 865 #define symbol_request(x) try_then_request_module(symbol_get(x), "symbol:" #x) 866 867 /* BELOW HERE ALL THESE ARE OBSOLETE AND WILL VANISH */ 868 869 #define __MODULE_STRING(x) __stringify(x) 870 871 #ifdef CONFIG_GENERIC_BUG 872 void module_bug_finalize(const Elf_Ehdr *, const Elf_Shdr *, 873 struct module *); 874 void module_bug_cleanup(struct module *); 875 876 #else /* !CONFIG_GENERIC_BUG */ 877 878 static inline void module_bug_finalize(const Elf_Ehdr *hdr, 879 const Elf_Shdr *sechdrs, 880 struct module *mod) 881 { 882 } 883 static inline void module_bug_cleanup(struct module *mod) {} 884 #endif /* CONFIG_GENERIC_BUG */ 885 886 #ifdef CONFIG_RETPOLINE 887 extern bool retpoline_module_ok(bool has_retpoline); 888 #else 889 static inline bool retpoline_module_ok(bool has_retpoline) 890 { 891 return true; 892 } 893 #endif 894 895 #ifdef CONFIG_MODULE_SIG 896 bool is_module_sig_enforced(void); 897 898 static inline bool module_sig_ok(struct module *module) 899 { 900 return module->sig_ok; 901 } 902 #else /* !CONFIG_MODULE_SIG */ 903 static inline bool is_module_sig_enforced(void) 904 { 905 return false; 906 } 907 908 static inline bool module_sig_ok(struct module *module) 909 { 910 return true; 911 } 912 #endif /* CONFIG_MODULE_SIG */ 913 914 #if defined(CONFIG_MODULES) && defined(CONFIG_KALLSYMS) 915 int module_kallsyms_on_each_symbol(const char *modname, 916 int (*fn)(void *, const char *, unsigned long), 917 void *data); 918 919 /* For kallsyms to ask for address resolution. namebuf should be at 920 * least KSYM_NAME_LEN long: a pointer to namebuf is returned if 921 * found, otherwise NULL. 922 */ 923 const char *module_address_lookup(unsigned long addr, 924 unsigned long *symbolsize, 925 unsigned long *offset, 926 char **modname, const unsigned char **modbuildid, 927 char *namebuf); 928 int lookup_module_symbol_name(unsigned long addr, char *symname); 929 int lookup_module_symbol_attrs(unsigned long addr, 930 unsigned long *size, 931 unsigned long *offset, 932 char *modname, 933 char *name); 934 935 /* Returns 0 and fills in value, defined and namebuf, or -ERANGE if 936 * symnum out of range. 937 */ 938 int module_get_kallsym(unsigned int symnum, unsigned long *value, char *type, 939 char *name, char *module_name, int *exported); 940 941 /* Look for this name: can be of form module:name. */ 942 unsigned long module_kallsyms_lookup_name(const char *name); 943 944 unsigned long find_kallsyms_symbol_value(struct module *mod, const char *name); 945 946 #else /* CONFIG_MODULES && CONFIG_KALLSYMS */ 947 948 static inline int module_kallsyms_on_each_symbol(const char *modname, 949 int (*fn)(void *, const char *, unsigned long), 950 void *data) 951 { 952 return -EOPNOTSUPP; 953 } 954 955 /* For kallsyms to ask for address resolution. NULL means not found. */ 956 static inline const char *module_address_lookup(unsigned long addr, 957 unsigned long *symbolsize, 958 unsigned long *offset, 959 char **modname, 960 const unsigned char **modbuildid, 961 char *namebuf) 962 { 963 return NULL; 964 } 965 966 static inline int lookup_module_symbol_name(unsigned long addr, char *symname) 967 { 968 return -ERANGE; 969 } 970 971 static inline int module_get_kallsym(unsigned int symnum, unsigned long *value, 972 char *type, char *name, 973 char *module_name, int *exported) 974 { 975 return -ERANGE; 976 } 977 978 static inline unsigned long module_kallsyms_lookup_name(const char *name) 979 { 980 return 0; 981 } 982 983 static inline unsigned long find_kallsyms_symbol_value(struct module *mod, 984 const char *name) 985 { 986 return 0; 987 } 988 989 #endif /* CONFIG_MODULES && CONFIG_KALLSYMS */ 990 991 #endif /* _LINUX_MODULE_H */ 992