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