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