1 /* SPDX-License-Identifier: (LGPL-2.1 OR BSD-2-Clause) */ 2 /* Copyright (c) 2018 Facebook */ 3 4 #ifndef __LIBBPF_BTF_H 5 #define __LIBBPF_BTF_H 6 7 #include <stdarg.h> 8 #include <stdbool.h> 9 #include <linux/btf.h> 10 #include <linux/types.h> 11 12 #include "libbpf_common.h" 13 14 #ifdef __cplusplus 15 extern "C" { 16 #endif 17 18 #define BTF_ELF_SEC ".BTF" 19 #define BTF_EXT_ELF_SEC ".BTF.ext" 20 #define MAPS_ELF_SEC ".maps" 21 22 struct btf; 23 struct btf_ext; 24 struct btf_type; 25 26 struct bpf_object; 27 28 enum btf_endianness { 29 BTF_LITTLE_ENDIAN = 0, 30 BTF_BIG_ENDIAN = 1, 31 }; 32 33 LIBBPF_API void btf__free(struct btf *btf); 34 35 LIBBPF_API struct btf *btf__new(const void *data, __u32 size); 36 LIBBPF_API struct btf *btf__new_split(const void *data, __u32 size, struct btf *base_btf); 37 LIBBPF_API struct btf *btf__new_empty(void); 38 LIBBPF_API struct btf *btf__new_empty_split(struct btf *base_btf); 39 40 LIBBPF_API struct btf *btf__parse(const char *path, struct btf_ext **btf_ext); 41 LIBBPF_API struct btf *btf__parse_split(const char *path, struct btf *base_btf); 42 LIBBPF_API struct btf *btf__parse_elf(const char *path, struct btf_ext **btf_ext); 43 LIBBPF_API struct btf *btf__parse_elf_split(const char *path, struct btf *base_btf); 44 LIBBPF_API struct btf *btf__parse_raw(const char *path); 45 LIBBPF_API struct btf *btf__parse_raw_split(const char *path, struct btf *base_btf); 46 47 LIBBPF_API struct btf *btf__load_vmlinux_btf(void); 48 LIBBPF_API struct btf *btf__load_module_btf(const char *module_name, struct btf *vmlinux_btf); 49 LIBBPF_API struct btf *libbpf_find_kernel_btf(void); 50 51 LIBBPF_API struct btf *btf__load_from_kernel_by_id(__u32 id); 52 LIBBPF_API struct btf *btf__load_from_kernel_by_id_split(__u32 id, struct btf *base_btf); 53 LIBBPF_API int btf__get_from_id(__u32 id, struct btf **btf); 54 55 LIBBPF_API int btf__finalize_data(struct bpf_object *obj, struct btf *btf); 56 LIBBPF_API int btf__load(struct btf *btf); 57 LIBBPF_API int btf__load_into_kernel(struct btf *btf); 58 LIBBPF_API __s32 btf__find_by_name(const struct btf *btf, 59 const char *type_name); 60 LIBBPF_API __s32 btf__find_by_name_kind(const struct btf *btf, 61 const char *type_name, __u32 kind); 62 LIBBPF_API __u32 btf__get_nr_types(const struct btf *btf); 63 LIBBPF_API const struct btf *btf__base_btf(const struct btf *btf); 64 LIBBPF_API const struct btf_type *btf__type_by_id(const struct btf *btf, 65 __u32 id); 66 LIBBPF_API size_t btf__pointer_size(const struct btf *btf); 67 LIBBPF_API int btf__set_pointer_size(struct btf *btf, size_t ptr_sz); 68 LIBBPF_API enum btf_endianness btf__endianness(const struct btf *btf); 69 LIBBPF_API int btf__set_endianness(struct btf *btf, enum btf_endianness endian); 70 LIBBPF_API __s64 btf__resolve_size(const struct btf *btf, __u32 type_id); 71 LIBBPF_API int btf__resolve_type(const struct btf *btf, __u32 type_id); 72 LIBBPF_API int btf__align_of(const struct btf *btf, __u32 id); 73 LIBBPF_API int btf__fd(const struct btf *btf); 74 LIBBPF_API void btf__set_fd(struct btf *btf, int fd); 75 LIBBPF_API const void *btf__get_raw_data(const struct btf *btf, __u32 *size); 76 LIBBPF_API const char *btf__name_by_offset(const struct btf *btf, __u32 offset); 77 LIBBPF_API const char *btf__str_by_offset(const struct btf *btf, __u32 offset); 78 LIBBPF_API int btf__get_map_kv_tids(const struct btf *btf, const char *map_name, 79 __u32 expected_key_size, 80 __u32 expected_value_size, 81 __u32 *key_type_id, __u32 *value_type_id); 82 83 LIBBPF_API struct btf_ext *btf_ext__new(__u8 *data, __u32 size); 84 LIBBPF_API void btf_ext__free(struct btf_ext *btf_ext); 85 LIBBPF_API const void *btf_ext__get_raw_data(const struct btf_ext *btf_ext, 86 __u32 *size); 87 LIBBPF_API LIBBPF_DEPRECATED("btf_ext__reloc_func_info was never meant as a public API and has wrong assumptions embedded in it; it will be removed in the future libbpf versions") 88 int btf_ext__reloc_func_info(const struct btf *btf, 89 const struct btf_ext *btf_ext, 90 const char *sec_name, __u32 insns_cnt, 91 void **func_info, __u32 *cnt); 92 LIBBPF_API LIBBPF_DEPRECATED("btf_ext__reloc_line_info was never meant as a public API and has wrong assumptions embedded in it; it will be removed in the future libbpf versions") 93 int btf_ext__reloc_line_info(const struct btf *btf, 94 const struct btf_ext *btf_ext, 95 const char *sec_name, __u32 insns_cnt, 96 void **line_info, __u32 *cnt); 97 LIBBPF_API __u32 btf_ext__func_info_rec_size(const struct btf_ext *btf_ext); 98 LIBBPF_API __u32 btf_ext__line_info_rec_size(const struct btf_ext *btf_ext); 99 100 LIBBPF_API int btf__find_str(struct btf *btf, const char *s); 101 LIBBPF_API int btf__add_str(struct btf *btf, const char *s); 102 LIBBPF_API int btf__add_type(struct btf *btf, const struct btf *src_btf, 103 const struct btf_type *src_type); 104 105 LIBBPF_API int btf__add_int(struct btf *btf, const char *name, size_t byte_sz, int encoding); 106 LIBBPF_API int btf__add_float(struct btf *btf, const char *name, size_t byte_sz); 107 LIBBPF_API int btf__add_ptr(struct btf *btf, int ref_type_id); 108 LIBBPF_API int btf__add_array(struct btf *btf, 109 int index_type_id, int elem_type_id, __u32 nr_elems); 110 /* struct/union construction APIs */ 111 LIBBPF_API int btf__add_struct(struct btf *btf, const char *name, __u32 sz); 112 LIBBPF_API int btf__add_union(struct btf *btf, const char *name, __u32 sz); 113 LIBBPF_API int btf__add_field(struct btf *btf, const char *name, int field_type_id, 114 __u32 bit_offset, __u32 bit_size); 115 116 /* enum construction APIs */ 117 LIBBPF_API int btf__add_enum(struct btf *btf, const char *name, __u32 bytes_sz); 118 LIBBPF_API int btf__add_enum_value(struct btf *btf, const char *name, __s64 value); 119 120 enum btf_fwd_kind { 121 BTF_FWD_STRUCT = 0, 122 BTF_FWD_UNION = 1, 123 BTF_FWD_ENUM = 2, 124 }; 125 126 LIBBPF_API int btf__add_fwd(struct btf *btf, const char *name, enum btf_fwd_kind fwd_kind); 127 LIBBPF_API int btf__add_typedef(struct btf *btf, const char *name, int ref_type_id); 128 LIBBPF_API int btf__add_volatile(struct btf *btf, int ref_type_id); 129 LIBBPF_API int btf__add_const(struct btf *btf, int ref_type_id); 130 LIBBPF_API int btf__add_restrict(struct btf *btf, int ref_type_id); 131 132 /* func and func_proto construction APIs */ 133 LIBBPF_API int btf__add_func(struct btf *btf, const char *name, 134 enum btf_func_linkage linkage, int proto_type_id); 135 LIBBPF_API int btf__add_func_proto(struct btf *btf, int ret_type_id); 136 LIBBPF_API int btf__add_func_param(struct btf *btf, const char *name, int type_id); 137 138 /* var & datasec construction APIs */ 139 LIBBPF_API int btf__add_var(struct btf *btf, const char *name, int linkage, int type_id); 140 LIBBPF_API int btf__add_datasec(struct btf *btf, const char *name, __u32 byte_sz); 141 LIBBPF_API int btf__add_datasec_var_info(struct btf *btf, int var_type_id, 142 __u32 offset, __u32 byte_sz); 143 144 struct btf_dedup_opts { 145 unsigned int dedup_table_size; 146 bool dont_resolve_fwds; 147 }; 148 149 LIBBPF_API int btf__dedup(struct btf *btf, struct btf_ext *btf_ext, 150 const struct btf_dedup_opts *opts); 151 152 struct btf_dump; 153 154 struct btf_dump_opts { 155 void *ctx; 156 }; 157 158 typedef void (*btf_dump_printf_fn_t)(void *ctx, const char *fmt, va_list args); 159 160 LIBBPF_API struct btf_dump *btf_dump__new(const struct btf *btf, 161 const struct btf_ext *btf_ext, 162 const struct btf_dump_opts *opts, 163 btf_dump_printf_fn_t printf_fn); 164 LIBBPF_API void btf_dump__free(struct btf_dump *d); 165 166 LIBBPF_API int btf_dump__dump_type(struct btf_dump *d, __u32 id); 167 168 struct btf_dump_emit_type_decl_opts { 169 /* size of this struct, for forward/backward compatiblity */ 170 size_t sz; 171 /* optional field name for type declaration, e.g.: 172 * - struct my_struct <FNAME> 173 * - void (*<FNAME>)(int) 174 * - char (*<FNAME>)[123] 175 */ 176 const char *field_name; 177 /* extra indentation level (in number of tabs) to emit for multi-line 178 * type declarations (e.g., anonymous struct); applies for lines 179 * starting from the second one (first line is assumed to have 180 * necessary indentation already 181 */ 182 int indent_level; 183 /* strip all the const/volatile/restrict mods */ 184 bool strip_mods; 185 size_t :0; 186 }; 187 #define btf_dump_emit_type_decl_opts__last_field strip_mods 188 189 LIBBPF_API int 190 btf_dump__emit_type_decl(struct btf_dump *d, __u32 id, 191 const struct btf_dump_emit_type_decl_opts *opts); 192 193 194 struct btf_dump_type_data_opts { 195 /* size of this struct, for forward/backward compatibility */ 196 size_t sz; 197 const char *indent_str; 198 int indent_level; 199 /* below match "show" flags for bpf_show_snprintf() */ 200 bool compact; /* no newlines/indentation */ 201 bool skip_names; /* skip member/type names */ 202 bool emit_zeroes; /* show 0-valued fields */ 203 size_t :0; 204 }; 205 #define btf_dump_type_data_opts__last_field emit_zeroes 206 207 LIBBPF_API int 208 btf_dump__dump_type_data(struct btf_dump *d, __u32 id, 209 const void *data, size_t data_sz, 210 const struct btf_dump_type_data_opts *opts); 211 212 /* 213 * A set of helpers for easier BTF types handling 214 */ 215 static inline __u16 btf_kind(const struct btf_type *t) 216 { 217 return BTF_INFO_KIND(t->info); 218 } 219 220 static inline __u16 btf_vlen(const struct btf_type *t) 221 { 222 return BTF_INFO_VLEN(t->info); 223 } 224 225 static inline bool btf_kflag(const struct btf_type *t) 226 { 227 return BTF_INFO_KFLAG(t->info); 228 } 229 230 static inline bool btf_is_void(const struct btf_type *t) 231 { 232 return btf_kind(t) == BTF_KIND_UNKN; 233 } 234 235 static inline bool btf_is_int(const struct btf_type *t) 236 { 237 return btf_kind(t) == BTF_KIND_INT; 238 } 239 240 static inline bool btf_is_ptr(const struct btf_type *t) 241 { 242 return btf_kind(t) == BTF_KIND_PTR; 243 } 244 245 static inline bool btf_is_array(const struct btf_type *t) 246 { 247 return btf_kind(t) == BTF_KIND_ARRAY; 248 } 249 250 static inline bool btf_is_struct(const struct btf_type *t) 251 { 252 return btf_kind(t) == BTF_KIND_STRUCT; 253 } 254 255 static inline bool btf_is_union(const struct btf_type *t) 256 { 257 return btf_kind(t) == BTF_KIND_UNION; 258 } 259 260 static inline bool btf_is_composite(const struct btf_type *t) 261 { 262 __u16 kind = btf_kind(t); 263 264 return kind == BTF_KIND_STRUCT || kind == BTF_KIND_UNION; 265 } 266 267 static inline bool btf_is_enum(const struct btf_type *t) 268 { 269 return btf_kind(t) == BTF_KIND_ENUM; 270 } 271 272 static inline bool btf_is_fwd(const struct btf_type *t) 273 { 274 return btf_kind(t) == BTF_KIND_FWD; 275 } 276 277 static inline bool btf_is_typedef(const struct btf_type *t) 278 { 279 return btf_kind(t) == BTF_KIND_TYPEDEF; 280 } 281 282 static inline bool btf_is_volatile(const struct btf_type *t) 283 { 284 return btf_kind(t) == BTF_KIND_VOLATILE; 285 } 286 287 static inline bool btf_is_const(const struct btf_type *t) 288 { 289 return btf_kind(t) == BTF_KIND_CONST; 290 } 291 292 static inline bool btf_is_restrict(const struct btf_type *t) 293 { 294 return btf_kind(t) == BTF_KIND_RESTRICT; 295 } 296 297 static inline bool btf_is_mod(const struct btf_type *t) 298 { 299 __u16 kind = btf_kind(t); 300 301 return kind == BTF_KIND_VOLATILE || 302 kind == BTF_KIND_CONST || 303 kind == BTF_KIND_RESTRICT; 304 } 305 306 static inline bool btf_is_func(const struct btf_type *t) 307 { 308 return btf_kind(t) == BTF_KIND_FUNC; 309 } 310 311 static inline bool btf_is_func_proto(const struct btf_type *t) 312 { 313 return btf_kind(t) == BTF_KIND_FUNC_PROTO; 314 } 315 316 static inline bool btf_is_var(const struct btf_type *t) 317 { 318 return btf_kind(t) == BTF_KIND_VAR; 319 } 320 321 static inline bool btf_is_datasec(const struct btf_type *t) 322 { 323 return btf_kind(t) == BTF_KIND_DATASEC; 324 } 325 326 static inline bool btf_is_float(const struct btf_type *t) 327 { 328 return btf_kind(t) == BTF_KIND_FLOAT; 329 } 330 331 static inline __u8 btf_int_encoding(const struct btf_type *t) 332 { 333 return BTF_INT_ENCODING(*(__u32 *)(t + 1)); 334 } 335 336 static inline __u8 btf_int_offset(const struct btf_type *t) 337 { 338 return BTF_INT_OFFSET(*(__u32 *)(t + 1)); 339 } 340 341 static inline __u8 btf_int_bits(const struct btf_type *t) 342 { 343 return BTF_INT_BITS(*(__u32 *)(t + 1)); 344 } 345 346 static inline struct btf_array *btf_array(const struct btf_type *t) 347 { 348 return (struct btf_array *)(t + 1); 349 } 350 351 static inline struct btf_enum *btf_enum(const struct btf_type *t) 352 { 353 return (struct btf_enum *)(t + 1); 354 } 355 356 static inline struct btf_member *btf_members(const struct btf_type *t) 357 { 358 return (struct btf_member *)(t + 1); 359 } 360 361 /* Get bit offset of a member with specified index. */ 362 static inline __u32 btf_member_bit_offset(const struct btf_type *t, 363 __u32 member_idx) 364 { 365 const struct btf_member *m = btf_members(t) + member_idx; 366 bool kflag = btf_kflag(t); 367 368 return kflag ? BTF_MEMBER_BIT_OFFSET(m->offset) : m->offset; 369 } 370 /* 371 * Get bitfield size of a member, assuming t is BTF_KIND_STRUCT or 372 * BTF_KIND_UNION. If member is not a bitfield, zero is returned. 373 */ 374 static inline __u32 btf_member_bitfield_size(const struct btf_type *t, 375 __u32 member_idx) 376 { 377 const struct btf_member *m = btf_members(t) + member_idx; 378 bool kflag = btf_kflag(t); 379 380 return kflag ? BTF_MEMBER_BITFIELD_SIZE(m->offset) : 0; 381 } 382 383 static inline struct btf_param *btf_params(const struct btf_type *t) 384 { 385 return (struct btf_param *)(t + 1); 386 } 387 388 static inline struct btf_var *btf_var(const struct btf_type *t) 389 { 390 return (struct btf_var *)(t + 1); 391 } 392 393 static inline struct btf_var_secinfo * 394 btf_var_secinfos(const struct btf_type *t) 395 { 396 return (struct btf_var_secinfo *)(t + 1); 397 } 398 399 #ifdef __cplusplus 400 } /* extern "C" */ 401 #endif 402 403 #endif /* __LIBBPF_BTF_H */ 404