1 /* SPDX-License-Identifier: (LGPL-2.1 OR BSD-2-Clause) */ 2 /* Copyright (c) 2018 Facebook */ 3 /*! \file */ 4 5 #ifndef __LIBBPF_BTF_H 6 #define __LIBBPF_BTF_H 7 8 #include <stdarg.h> 9 #include <stdbool.h> 10 #include <linux/btf.h> 11 #include <linux/types.h> 12 13 #include "libbpf_common.h" 14 15 #ifdef __cplusplus 16 extern "C" { 17 #endif 18 19 #define BTF_ELF_SEC ".BTF" 20 #define BTF_EXT_ELF_SEC ".BTF.ext" 21 #define BTF_BASE_ELF_SEC ".BTF.base" 22 #define MAPS_ELF_SEC ".maps" 23 24 struct btf; 25 struct btf_ext; 26 struct btf_type; 27 28 struct bpf_object; 29 30 enum btf_endianness { 31 BTF_LITTLE_ENDIAN = 0, 32 BTF_BIG_ENDIAN = 1, 33 }; 34 35 /** 36 * @brief **btf__free()** frees all data of a BTF object 37 * @param btf BTF object to free 38 */ 39 LIBBPF_API void btf__free(struct btf *btf); 40 41 /** 42 * @brief **btf__new()** creates a new instance of a BTF object from the raw 43 * bytes of an ELF's BTF section 44 * @param data raw bytes 45 * @param size number of bytes passed in `data` 46 * @return new BTF object instance which has to be eventually freed with 47 * **btf__free()** 48 * 49 * On error, error-code-encoded-as-pointer is returned, not a NULL. To extract 50 * error code from such a pointer `libbpf_get_error()` should be used. If 51 * `libbpf_set_strict_mode(LIBBPF_STRICT_CLEAN_PTRS)` is enabled, NULL is 52 * returned on error instead. In both cases thread-local `errno` variable is 53 * always set to error code as well. 54 */ 55 LIBBPF_API struct btf *btf__new(const void *data, __u32 size); 56 57 /** 58 * @brief **btf__new_split()** create a new instance of a BTF object from the 59 * provided raw data bytes. It takes another BTF instance, **base_btf**, which 60 * serves as a base BTF, which is extended by types in a newly created BTF 61 * instance 62 * @param data raw bytes 63 * @param size length of raw bytes 64 * @param base_btf the base BTF object 65 * @return new BTF object instance which has to be eventually freed with 66 * **btf__free()** 67 * 68 * If *base_btf* is NULL, `btf__new_split()` is equivalent to `btf__new()` and 69 * creates non-split BTF. 70 * 71 * On error, error-code-encoded-as-pointer is returned, not a NULL. To extract 72 * error code from such a pointer `libbpf_get_error()` should be used. If 73 * `libbpf_set_strict_mode(LIBBPF_STRICT_CLEAN_PTRS)` is enabled, NULL is 74 * returned on error instead. In both cases thread-local `errno` variable is 75 * always set to error code as well. 76 */ 77 LIBBPF_API struct btf *btf__new_split(const void *data, __u32 size, struct btf *base_btf); 78 79 /** 80 * @brief **btf__new_empty()** creates an empty BTF object. Use 81 * `btf__add_*()` to populate such BTF object. 82 * @return new BTF object instance which has to be eventually freed with 83 * **btf__free()** 84 * 85 * On error, error-code-encoded-as-pointer is returned, not a NULL. To extract 86 * error code from such a pointer `libbpf_get_error()` should be used. If 87 * `libbpf_set_strict_mode(LIBBPF_STRICT_CLEAN_PTRS)` is enabled, NULL is 88 * returned on error instead. In both cases thread-local `errno` variable is 89 * always set to error code as well. 90 */ 91 LIBBPF_API struct btf *btf__new_empty(void); 92 93 /** 94 * @brief **btf__new_empty_split()** creates an unpopulated BTF object from an 95 * ELF BTF section except with a base BTF on top of which split BTF should be 96 * based 97 * @param base_btf base BTF object 98 * @return new BTF object instance which has to be eventually freed with 99 * **btf__free()** 100 * 101 * If *base_btf* is NULL, `btf__new_empty_split()` is equivalent to 102 * `btf__new_empty()` and creates non-split BTF. 103 * 104 * On error, error-code-encoded-as-pointer is returned, not a NULL. To extract 105 * error code from such a pointer `libbpf_get_error()` should be used. If 106 * `libbpf_set_strict_mode(LIBBPF_STRICT_CLEAN_PTRS)` is enabled, NULL is 107 * returned on error instead. In both cases thread-local `errno` variable is 108 * always set to error code as well. 109 */ 110 LIBBPF_API struct btf *btf__new_empty_split(struct btf *base_btf); 111 112 struct btf_new_opts { 113 size_t sz; 114 struct btf *base_btf; /* optional base BTF */ 115 bool add_layout; /* add BTF layout information */ 116 size_t:0; 117 }; 118 #define btf_new_opts__last_field add_layout 119 120 /** 121 * @brief **btf__new_empty_opts()** creates an unpopulated BTF object with 122 * optional *base_btf* and BTF kind layout description if *add_layout* 123 * is set 124 * @return new BTF object instance which has to be eventually freed with 125 * **btf__free()** 126 * 127 * On error, NULL is returned and the thread-local `errno` variable is 128 * set to the error code. 129 */ 130 LIBBPF_API struct btf *btf__new_empty_opts(struct btf_new_opts *opts); 131 132 /** 133 * @brief **btf__distill_base()** creates new versions of the split BTF 134 * *src_btf* and its base BTF. The new base BTF will only contain the types 135 * needed to improve robustness of the split BTF to small changes in base BTF. 136 * When that split BTF is loaded against a (possibly changed) base, this 137 * distilled base BTF will help update references to that (possibly changed) 138 * base BTF. 139 * @param src_btf source split BTF object 140 * @param new_base_btf pointer to where the new base BTF object pointer will be stored 141 * @param new_split_btf pointer to where the new split BTF object pointer will be stored 142 * @return 0 on success; negative error code, otherwise 143 * 144 * Both the new split and its associated new base BTF must be freed by 145 * the caller. 146 * 147 * If successful, 0 is returned and **new_base_btf** and **new_split_btf** 148 * will point at new base/split BTF. Both the new split and its associated 149 * new base BTF must be freed by the caller. 150 * 151 * A negative value is returned on error and the thread-local `errno` variable 152 * is set to the error code as well. 153 */ 154 LIBBPF_API int btf__distill_base(const struct btf *src_btf, struct btf **new_base_btf, 155 struct btf **new_split_btf); 156 157 LIBBPF_API struct btf *btf__parse(const char *path, struct btf_ext **btf_ext); 158 LIBBPF_API struct btf *btf__parse_split(const char *path, struct btf *base_btf); 159 LIBBPF_API struct btf *btf__parse_elf(const char *path, struct btf_ext **btf_ext); 160 LIBBPF_API struct btf *btf__parse_elf_split(const char *path, struct btf *base_btf); 161 LIBBPF_API struct btf *btf__parse_raw(const char *path); 162 LIBBPF_API struct btf *btf__parse_raw_split(const char *path, struct btf *base_btf); 163 164 LIBBPF_API struct btf *btf__load_vmlinux_btf(void); 165 LIBBPF_API struct btf *btf__load_module_btf(const char *module_name, struct btf *vmlinux_btf); 166 167 LIBBPF_API struct btf *btf__load_from_kernel_by_id(__u32 id); 168 LIBBPF_API struct btf *btf__load_from_kernel_by_id_split(__u32 id, struct btf *base_btf); 169 170 LIBBPF_API int btf__load_into_kernel(struct btf *btf); 171 LIBBPF_API __s32 btf__find_by_name(const struct btf *btf, 172 const char *type_name); 173 LIBBPF_API __s32 btf__find_by_name_kind(const struct btf *btf, 174 const char *type_name, __u32 kind); 175 LIBBPF_API __s32 btf__find_by_name_kind_own(const struct btf *btf, 176 const char *type_name, __u32 kind); 177 LIBBPF_API __u32 btf__type_cnt(const struct btf *btf); 178 LIBBPF_API const struct btf *btf__base_btf(const struct btf *btf); 179 LIBBPF_API const struct btf_type *btf__type_by_id(const struct btf *btf, 180 __u32 id); 181 LIBBPF_API size_t btf__pointer_size(const struct btf *btf); 182 LIBBPF_API int btf__set_pointer_size(struct btf *btf, size_t ptr_sz); 183 LIBBPF_API enum btf_endianness btf__endianness(const struct btf *btf); 184 LIBBPF_API int btf__set_endianness(struct btf *btf, enum btf_endianness endian); 185 LIBBPF_API __s64 btf__resolve_size(const struct btf *btf, __u32 type_id); 186 LIBBPF_API int btf__resolve_type(const struct btf *btf, __u32 type_id); 187 LIBBPF_API int btf__align_of(const struct btf *btf, __u32 id); 188 LIBBPF_API int btf__fd(const struct btf *btf); 189 LIBBPF_API void btf__set_fd(struct btf *btf, int fd); 190 LIBBPF_API const void *btf__raw_data(const struct btf *btf, __u32 *size); 191 LIBBPF_API const char *btf__name_by_offset(const struct btf *btf, __u32 offset); 192 LIBBPF_API const char *btf__str_by_offset(const struct btf *btf, __u32 offset); 193 194 LIBBPF_API struct btf_ext *btf_ext__new(const __u8 *data, __u32 size); 195 LIBBPF_API void btf_ext__free(struct btf_ext *btf_ext); 196 LIBBPF_API const void *btf_ext__raw_data(const struct btf_ext *btf_ext, __u32 *size); 197 LIBBPF_API enum btf_endianness btf_ext__endianness(const struct btf_ext *btf_ext); 198 LIBBPF_API int btf_ext__set_endianness(struct btf_ext *btf_ext, 199 enum btf_endianness endian); 200 201 LIBBPF_API int btf__find_str(struct btf *btf, const char *s); 202 LIBBPF_API int btf__add_str(struct btf *btf, const char *s); 203 LIBBPF_API int btf__add_type(struct btf *btf, const struct btf *src_btf, 204 const struct btf_type *src_type); 205 /** 206 * @brief **btf__add_btf()** appends all the BTF types from *src_btf* into *btf* 207 * @param btf BTF object which all the BTF types and strings are added to 208 * @param src_btf BTF object which all BTF types and referenced strings are copied from 209 * @return BTF type ID of the first appended BTF type, or negative error code 210 * 211 * **btf__add_btf()** can be used to simply and efficiently append the entire 212 * contents of one BTF object to another one. All the BTF type data is copied 213 * over, all referenced type IDs are adjusted by adding a necessary ID offset. 214 * Only strings referenced from BTF types are copied over and deduplicated, so 215 * if there were some unused strings in *src_btf*, those won't be copied over, 216 * which is consistent with the general string deduplication semantics of BTF 217 * writing APIs. 218 * 219 * If any error is encountered during this process, the contents of *btf* is 220 * left intact, which means that **btf__add_btf()** follows the transactional 221 * semantics and the operation as a whole is all-or-nothing. 222 * 223 * *src_btf* has to be non-split BTF, as of now copying types from split BTF 224 * is not supported and will result in -ENOTSUP error code returned. 225 */ 226 LIBBPF_API int btf__add_btf(struct btf *btf, const struct btf *src_btf); 227 228 LIBBPF_API int btf__add_int(struct btf *btf, const char *name, size_t byte_sz, int encoding); 229 LIBBPF_API int btf__add_float(struct btf *btf, const char *name, size_t byte_sz); 230 LIBBPF_API int btf__add_ptr(struct btf *btf, int ref_type_id); 231 LIBBPF_API int btf__add_array(struct btf *btf, 232 int index_type_id, int elem_type_id, __u32 nr_elems); 233 /* struct/union construction APIs */ 234 LIBBPF_API int btf__add_struct(struct btf *btf, const char *name, __u32 sz); 235 LIBBPF_API int btf__add_union(struct btf *btf, const char *name, __u32 sz); 236 LIBBPF_API int btf__add_field(struct btf *btf, const char *name, int field_type_id, 237 __u32 bit_offset, __u32 bit_size); 238 239 /* enum construction APIs */ 240 LIBBPF_API int btf__add_enum(struct btf *btf, const char *name, __u32 bytes_sz); 241 LIBBPF_API int btf__add_enum_value(struct btf *btf, const char *name, __s64 value); 242 LIBBPF_API int btf__add_enum64(struct btf *btf, const char *name, __u32 bytes_sz, bool is_signed); 243 LIBBPF_API int btf__add_enum64_value(struct btf *btf, const char *name, __u64 value); 244 245 enum btf_fwd_kind { 246 BTF_FWD_STRUCT = 0, 247 BTF_FWD_UNION = 1, 248 BTF_FWD_ENUM = 2, 249 }; 250 251 LIBBPF_API int btf__add_fwd(struct btf *btf, const char *name, enum btf_fwd_kind fwd_kind); 252 LIBBPF_API int btf__add_typedef(struct btf *btf, const char *name, int ref_type_id); 253 LIBBPF_API int btf__add_volatile(struct btf *btf, int ref_type_id); 254 LIBBPF_API int btf__add_const(struct btf *btf, int ref_type_id); 255 LIBBPF_API int btf__add_restrict(struct btf *btf, int ref_type_id); 256 LIBBPF_API int btf__add_type_tag(struct btf *btf, const char *value, int ref_type_id); 257 LIBBPF_API int btf__add_type_attr(struct btf *btf, const char *value, int ref_type_id); 258 259 /* func and func_proto construction APIs */ 260 LIBBPF_API int btf__add_func(struct btf *btf, const char *name, 261 enum btf_func_linkage linkage, int proto_type_id); 262 LIBBPF_API int btf__add_func_proto(struct btf *btf, int ret_type_id); 263 LIBBPF_API int btf__add_func_param(struct btf *btf, const char *name, int type_id); 264 265 /* var & datasec construction APIs */ 266 LIBBPF_API int btf__add_var(struct btf *btf, const char *name, int linkage, int type_id); 267 LIBBPF_API int btf__add_datasec(struct btf *btf, const char *name, __u32 byte_sz); 268 LIBBPF_API int btf__add_datasec_var_info(struct btf *btf, int var_type_id, 269 __u32 offset, __u32 byte_sz); 270 271 /* tag construction API */ 272 LIBBPF_API int btf__add_decl_tag(struct btf *btf, const char *value, int ref_type_id, 273 int component_idx); 274 LIBBPF_API int btf__add_decl_attr(struct btf *btf, const char *value, int ref_type_id, 275 int component_idx); 276 277 struct btf_dedup_opts { 278 size_t sz; 279 /* optional .BTF.ext info to dedup along the main BTF info */ 280 struct btf_ext *btf_ext; 281 /* force hash collisions (used for testing) */ 282 bool force_collisions; 283 size_t :0; 284 }; 285 #define btf_dedup_opts__last_field force_collisions 286 287 LIBBPF_API int btf__dedup(struct btf *btf, const struct btf_dedup_opts *opts); 288 289 /** 290 * @brief **btf__relocate()** will check the split BTF *btf* for references 291 * to base BTF kinds, and verify those references are compatible with 292 * *base_btf*; if they are, *btf* is adjusted such that is re-parented to 293 * *base_btf* and type ids and strings are adjusted to accommodate this. 294 * @param btf split BTF object to relocate 295 * @param base_btf base BTF object 296 * @return 0 on success; negative error code, otherwise 297 * 298 * If successful, 0 is returned and **btf** now has **base_btf** as its 299 * base. 300 * 301 * A negative value is returned on error and the thread-local `errno` variable 302 * is set to the error code as well. 303 */ 304 LIBBPF_API int btf__relocate(struct btf *btf, const struct btf *base_btf); 305 306 struct btf_permute_opts { 307 size_t sz; 308 /* optional .BTF.ext info along the main BTF info */ 309 struct btf_ext *btf_ext; 310 size_t :0; 311 }; 312 #define btf_permute_opts__last_field btf_ext 313 314 /** 315 * @brief **btf__permute()** rearranges BTF types in-place according to a specified ID mapping 316 * @param btf BTF object to permute 317 * @param id_map Array mapping original type IDs to new IDs 318 * @param id_map_cnt Number of elements in @id_map 319 * @param opts Optional parameters, including BTF extension data for reference updates 320 * @return 0 on success, negative error code on failure 321 * 322 * **btf__permute()** reorders BTF types based on the provided @id_map array, 323 * updating all internal type references to maintain consistency. The function 324 * operates in-place, modifying the BTF object directly. 325 * 326 * For **base BTF**: 327 * - @id_map must include all types from ID 0 to `btf__type_cnt(btf) - 1` 328 * - @id_map_cnt must be `btf__type_cnt(btf)` 329 * - Mapping is defined as `id_map[original_id] = new_id` 330 * - `id_map[0]` must be 0 (void type cannot be moved) 331 * 332 * For **split BTF**: 333 * - @id_map must include only split types (types added on top of the base BTF) 334 * - @id_map_cnt must be `btf__type_cnt(btf) - btf__type_cnt(btf__base_btf(btf))` 335 * - Mapping is defined as `id_map[original_id - start_id] = new_id` 336 * - `start_id` equals `btf__type_cnt(btf__base_btf(btf))` 337 * 338 * After permutation, all type references within the BTF data and optional 339 * BTF extension (if provided via @opts) are updated automatically. 340 * 341 * On error, returns a negative error code and sets errno: 342 * - `-EINVAL`: Invalid parameters or invalid ID mapping 343 * - `-ENOMEM`: Memory allocation failure 344 */ 345 LIBBPF_API int btf__permute(struct btf *btf, __u32 *id_map, __u32 id_map_cnt, 346 const struct btf_permute_opts *opts); 347 348 struct btf_dump; 349 350 struct btf_dump_opts { 351 size_t sz; 352 }; 353 #define btf_dump_opts__last_field sz 354 355 typedef void (*btf_dump_printf_fn_t)(void *ctx, const char *fmt, va_list args); 356 357 LIBBPF_API struct btf_dump *btf_dump__new(const struct btf *btf, 358 btf_dump_printf_fn_t printf_fn, 359 void *ctx, 360 const struct btf_dump_opts *opts); 361 362 LIBBPF_API void btf_dump__free(struct btf_dump *d); 363 364 LIBBPF_API int btf_dump__dump_type(struct btf_dump *d, __u32 id); 365 366 struct btf_dump_emit_type_decl_opts { 367 /* size of this struct, for forward/backward compatibility */ 368 size_t sz; 369 /* optional field name for type declaration, e.g.: 370 * - struct my_struct <FNAME> 371 * - void (*<FNAME>)(int) 372 * - char (*<FNAME>)[123] 373 */ 374 const char *field_name; 375 /* extra indentation level (in number of tabs) to emit for multi-line 376 * type declarations (e.g., anonymous struct); applies for lines 377 * starting from the second one (first line is assumed to have 378 * necessary indentation already 379 */ 380 int indent_level; 381 /* strip all the const/volatile/restrict mods */ 382 bool strip_mods; 383 size_t :0; 384 }; 385 #define btf_dump_emit_type_decl_opts__last_field strip_mods 386 387 LIBBPF_API int 388 btf_dump__emit_type_decl(struct btf_dump *d, __u32 id, 389 const struct btf_dump_emit_type_decl_opts *opts); 390 391 392 struct btf_dump_type_data_opts { 393 /* size of this struct, for forward/backward compatibility */ 394 size_t sz; 395 const char *indent_str; 396 int indent_level; 397 /* below match "show" flags for bpf_show_snprintf() */ 398 bool compact; /* no newlines/indentation */ 399 bool skip_names; /* skip member/type names */ 400 bool emit_zeroes; /* show 0-valued fields */ 401 bool emit_strings; /* print char arrays as strings */ 402 size_t :0; 403 }; 404 #define btf_dump_type_data_opts__last_field emit_strings 405 406 LIBBPF_API int 407 btf_dump__dump_type_data(struct btf_dump *d, __u32 id, 408 const void *data, size_t data_sz, 409 const struct btf_dump_type_data_opts *opts); 410 411 /* 412 * A set of helpers for easier BTF types handling. 413 * 414 * The inline functions below rely on constants from the kernel headers which 415 * may not be available for applications including this header file. To avoid 416 * compilation errors, we define all the constants here that were added after 417 * the initial introduction of the BTF_KIND* constants. 418 */ 419 #ifndef BTF_KIND_FUNC 420 #define BTF_KIND_FUNC 12 /* Function */ 421 #define BTF_KIND_FUNC_PROTO 13 /* Function Proto */ 422 #endif 423 #ifndef BTF_KIND_VAR 424 #define BTF_KIND_VAR 14 /* Variable */ 425 #define BTF_KIND_DATASEC 15 /* Section */ 426 #endif 427 #ifndef BTF_KIND_FLOAT 428 #define BTF_KIND_FLOAT 16 /* Floating point */ 429 #endif 430 /* The kernel header switched to enums, so the following were never #defined */ 431 #define BTF_KIND_DECL_TAG 17 /* Decl Tag */ 432 #define BTF_KIND_TYPE_TAG 18 /* Type Tag */ 433 #define BTF_KIND_ENUM64 19 /* Enum for up-to 64bit values */ 434 435 static inline __u16 btf_kind(const struct btf_type *t) 436 { 437 return BTF_INFO_KIND(t->info); 438 } 439 440 static inline __u32 btf_vlen(const struct btf_type *t) 441 { 442 return BTF_INFO_VLEN(t->info); 443 } 444 445 static inline bool btf_kflag(const struct btf_type *t) 446 { 447 return BTF_INFO_KFLAG(t->info); 448 } 449 450 static inline bool btf_is_void(const struct btf_type *t) 451 { 452 return btf_kind(t) == BTF_KIND_UNKN; 453 } 454 455 static inline bool btf_is_int(const struct btf_type *t) 456 { 457 return btf_kind(t) == BTF_KIND_INT; 458 } 459 460 static inline bool btf_is_ptr(const struct btf_type *t) 461 { 462 return btf_kind(t) == BTF_KIND_PTR; 463 } 464 465 static inline bool btf_is_array(const struct btf_type *t) 466 { 467 return btf_kind(t) == BTF_KIND_ARRAY; 468 } 469 470 static inline bool btf_is_struct(const struct btf_type *t) 471 { 472 return btf_kind(t) == BTF_KIND_STRUCT; 473 } 474 475 static inline bool btf_is_union(const struct btf_type *t) 476 { 477 return btf_kind(t) == BTF_KIND_UNION; 478 } 479 480 static inline bool btf_is_composite(const struct btf_type *t) 481 { 482 __u16 kind = btf_kind(t); 483 484 return kind == BTF_KIND_STRUCT || kind == BTF_KIND_UNION; 485 } 486 487 static inline bool btf_is_enum(const struct btf_type *t) 488 { 489 return btf_kind(t) == BTF_KIND_ENUM; 490 } 491 492 static inline bool btf_is_enum64(const struct btf_type *t) 493 { 494 return btf_kind(t) == BTF_KIND_ENUM64; 495 } 496 497 static inline bool btf_is_fwd(const struct btf_type *t) 498 { 499 return btf_kind(t) == BTF_KIND_FWD; 500 } 501 502 static inline bool btf_is_typedef(const struct btf_type *t) 503 { 504 return btf_kind(t) == BTF_KIND_TYPEDEF; 505 } 506 507 static inline bool btf_is_volatile(const struct btf_type *t) 508 { 509 return btf_kind(t) == BTF_KIND_VOLATILE; 510 } 511 512 static inline bool btf_is_const(const struct btf_type *t) 513 { 514 return btf_kind(t) == BTF_KIND_CONST; 515 } 516 517 static inline bool btf_is_restrict(const struct btf_type *t) 518 { 519 return btf_kind(t) == BTF_KIND_RESTRICT; 520 } 521 522 static inline bool btf_is_mod(const struct btf_type *t) 523 { 524 __u16 kind = btf_kind(t); 525 526 return kind == BTF_KIND_VOLATILE || 527 kind == BTF_KIND_CONST || 528 kind == BTF_KIND_RESTRICT || 529 kind == BTF_KIND_TYPE_TAG; 530 } 531 532 static inline bool btf_is_func(const struct btf_type *t) 533 { 534 return btf_kind(t) == BTF_KIND_FUNC; 535 } 536 537 static inline bool btf_is_func_proto(const struct btf_type *t) 538 { 539 return btf_kind(t) == BTF_KIND_FUNC_PROTO; 540 } 541 542 static inline bool btf_is_var(const struct btf_type *t) 543 { 544 return btf_kind(t) == BTF_KIND_VAR; 545 } 546 547 static inline bool btf_is_datasec(const struct btf_type *t) 548 { 549 return btf_kind(t) == BTF_KIND_DATASEC; 550 } 551 552 static inline bool btf_is_float(const struct btf_type *t) 553 { 554 return btf_kind(t) == BTF_KIND_FLOAT; 555 } 556 557 static inline bool btf_is_decl_tag(const struct btf_type *t) 558 { 559 return btf_kind(t) == BTF_KIND_DECL_TAG; 560 } 561 562 static inline bool btf_is_type_tag(const struct btf_type *t) 563 { 564 return btf_kind(t) == BTF_KIND_TYPE_TAG; 565 } 566 567 static inline bool btf_is_any_enum(const struct btf_type *t) 568 { 569 return btf_is_enum(t) || btf_is_enum64(t); 570 } 571 572 static inline bool btf_kind_core_compat(const struct btf_type *t1, 573 const struct btf_type *t2) 574 { 575 return btf_kind(t1) == btf_kind(t2) || 576 (btf_is_any_enum(t1) && btf_is_any_enum(t2)); 577 } 578 579 static inline __u8 btf_int_encoding(const struct btf_type *t) 580 { 581 return BTF_INT_ENCODING(*(__u32 *)(t + 1)); 582 } 583 584 static inline __u8 btf_int_offset(const struct btf_type *t) 585 { 586 return BTF_INT_OFFSET(*(__u32 *)(t + 1)); 587 } 588 589 static inline __u8 btf_int_bits(const struct btf_type *t) 590 { 591 return BTF_INT_BITS(*(__u32 *)(t + 1)); 592 } 593 594 static inline struct btf_array *btf_array(const struct btf_type *t) 595 { 596 return (struct btf_array *)(t + 1); 597 } 598 599 static inline struct btf_enum *btf_enum(const struct btf_type *t) 600 { 601 return (struct btf_enum *)(t + 1); 602 } 603 604 struct btf_enum64; 605 606 static inline struct btf_enum64 *btf_enum64(const struct btf_type *t) 607 { 608 return (struct btf_enum64 *)(t + 1); 609 } 610 611 static inline __u64 btf_enum64_value(const struct btf_enum64 *e) 612 { 613 /* struct btf_enum64 is introduced in Linux 6.0, which is very 614 * bleeding-edge. Here we are avoiding relying on struct btf_enum64 615 * definition coming from kernel UAPI headers to support wider range 616 * of system-wide kernel headers. 617 * 618 * Given this header can be also included from C++ applications, that 619 * further restricts C tricks we can use (like using compatible 620 * anonymous struct). So just treat struct btf_enum64 as 621 * a three-element array of u32 and access second (lo32) and third 622 * (hi32) elements directly. 623 * 624 * For reference, here is a struct btf_enum64 definition: 625 * 626 * const struct btf_enum64 { 627 * __u32 name_off; 628 * __u32 val_lo32; 629 * __u32 val_hi32; 630 * }; 631 */ 632 const __u32 *e64 = (const __u32 *)e; 633 634 return ((__u64)e64[2] << 32) | e64[1]; 635 } 636 637 static inline struct btf_member *btf_members(const struct btf_type *t) 638 { 639 return (struct btf_member *)(t + 1); 640 } 641 642 /* Get bit offset of a member with specified index. */ 643 static inline __u32 btf_member_bit_offset(const struct btf_type *t, 644 __u32 member_idx) 645 { 646 const struct btf_member *m = btf_members(t) + member_idx; 647 bool kflag = btf_kflag(t); 648 649 return kflag ? BTF_MEMBER_BIT_OFFSET(m->offset) : m->offset; 650 } 651 /* 652 * Get bitfield size of a member, assuming t is BTF_KIND_STRUCT or 653 * BTF_KIND_UNION. If member is not a bitfield, zero is returned. 654 */ 655 static inline __u32 btf_member_bitfield_size(const struct btf_type *t, 656 __u32 member_idx) 657 { 658 const struct btf_member *m = btf_members(t) + member_idx; 659 bool kflag = btf_kflag(t); 660 661 return kflag ? BTF_MEMBER_BITFIELD_SIZE(m->offset) : 0; 662 } 663 664 static inline struct btf_param *btf_params(const struct btf_type *t) 665 { 666 return (struct btf_param *)(t + 1); 667 } 668 669 static inline struct btf_var *btf_var(const struct btf_type *t) 670 { 671 return (struct btf_var *)(t + 1); 672 } 673 674 static inline struct btf_var_secinfo * 675 btf_var_secinfos(const struct btf_type *t) 676 { 677 return (struct btf_var_secinfo *)(t + 1); 678 } 679 680 struct btf_decl_tag; 681 static inline struct btf_decl_tag *btf_decl_tag(const struct btf_type *t) 682 { 683 return (struct btf_decl_tag *)(t + 1); 684 } 685 686 #ifdef __cplusplus 687 } /* extern "C" */ 688 #endif 689 690 #endif /* __LIBBPF_BTF_H */ 691