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