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