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