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