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 15extern "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 22struct btf; 23struct btf_ext; 24struct btf_type; 25 26struct bpf_object; 27 28enum btf_endianness { 29 BTF_LITTLE_ENDIAN = 0, 30 BTF_BIG_ENDIAN = 1, 31}; 32 33LIBBPF_API void btf__free(struct btf *btf); 34LIBBPF_API struct btf *btf__new(const void *data, __u32 size); 35LIBBPF_API struct btf *btf__new_empty(void); 36LIBBPF_API struct btf *btf__parse(const char *path, struct btf_ext **btf_ext); 37LIBBPF_API struct btf *btf__parse_elf(const char *path, struct btf_ext **btf_ext); 38LIBBPF_API struct btf *btf__parse_raw(const char *path); 39LIBBPF_API int btf__finalize_data(struct bpf_object *obj, struct btf *btf); 40LIBBPF_API int btf__load(struct btf *btf); 41LIBBPF_API __s32 btf__find_by_name(const struct btf *btf, 42 const char *type_name); 43LIBBPF_API __s32 btf__find_by_name_kind(const struct btf *btf, 44 const char *type_name, __u32 kind); 45LIBBPF_API __u32 btf__get_nr_types(const struct btf *btf); 46LIBBPF_API const struct btf_type *btf__type_by_id(const struct btf *btf, 47 __u32 id); 48LIBBPF_API size_t btf__pointer_size(const struct btf *btf); 49LIBBPF_API int btf__set_pointer_size(struct btf *btf, size_t ptr_sz); 50LIBBPF_API enum btf_endianness btf__endianness(const struct btf *btf); 51LIBBPF_API int btf__set_endianness(struct btf *btf, enum btf_endianness endian); 52LIBBPF_API __s64 btf__resolve_size(const struct btf *btf, __u32 type_id); 53LIBBPF_API int btf__resolve_type(const struct btf *btf, __u32 type_id); 54LIBBPF_API int btf__align_of(const struct btf *btf, __u32 id); 55LIBBPF_API int btf__fd(const struct btf *btf); 56LIBBPF_API void btf__set_fd(struct btf *btf, int fd); 57LIBBPF_API const void *btf__get_raw_data(const struct btf *btf, __u32 *size); 58LIBBPF_API const char *btf__name_by_offset(const struct btf *btf, __u32 offset); 59LIBBPF_API const char *btf__str_by_offset(const struct btf *btf, __u32 offset); 60LIBBPF_API int btf__get_from_id(__u32 id, struct btf **btf); 61LIBBPF_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 66LIBBPF_API struct btf_ext *btf_ext__new(__u8 *data, __u32 size); 67LIBBPF_API void btf_ext__free(struct btf_ext *btf_ext); 68LIBBPF_API const void *btf_ext__get_raw_data(const struct btf_ext *btf_ext, 69 __u32 *size); 70LIBBPF_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") 71int 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); 75LIBBPF_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") 76int 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); 80LIBBPF_API __u32 btf_ext__func_info_rec_size(const struct btf_ext *btf_ext); 81LIBBPF_API __u32 btf_ext__line_info_rec_size(const struct btf_ext *btf_ext); 82 83LIBBPF_API struct btf *libbpf_find_kernel_btf(void); 84 85LIBBPF_API int btf__find_str(struct btf *btf, const char *s); 86LIBBPF_API int btf__add_str(struct btf *btf, const char *s); 87 88LIBBPF_API int btf__add_int(struct btf *btf, const char *name, size_t byte_sz, int encoding); 89LIBBPF_API int btf__add_ptr(struct btf *btf, int ref_type_id); 90LIBBPF_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 */ 93LIBBPF_API int btf__add_struct(struct btf *btf, const char *name, __u32 sz); 94LIBBPF_API int btf__add_union(struct btf *btf, const char *name, __u32 sz); 95LIBBPF_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 */ 99LIBBPF_API int btf__add_enum(struct btf *btf, const char *name, __u32 bytes_sz); 100LIBBPF_API int btf__add_enum_value(struct btf *btf, const char *name, __s64 value); 101 102enum btf_fwd_kind { 103 BTF_FWD_STRUCT = 0, 104 BTF_FWD_UNION = 1, 105 BTF_FWD_ENUM = 2, 106}; 107 108LIBBPF_API int btf__add_fwd(struct btf *btf, const char *name, enum btf_fwd_kind fwd_kind); 109LIBBPF_API int btf__add_typedef(struct btf *btf, const char *name, int ref_type_id); 110LIBBPF_API int btf__add_volatile(struct btf *btf, int ref_type_id); 111LIBBPF_API int btf__add_const(struct btf *btf, int ref_type_id); 112LIBBPF_API int btf__add_restrict(struct btf *btf, int ref_type_id); 113 114/* func and func_proto construction APIs */ 115LIBBPF_API int btf__add_func(struct btf *btf, const char *name, 116 enum btf_func_linkage linkage, int proto_type_id); 117LIBBPF_API int btf__add_func_proto(struct btf *btf, int ret_type_id); 118LIBBPF_API int btf__add_func_param(struct btf *btf, const char *name, int type_id); 119 120/* var & datasec construction APIs */ 121LIBBPF_API int btf__add_var(struct btf *btf, const char *name, int linkage, int type_id); 122LIBBPF_API int btf__add_datasec(struct btf *btf, const char *name, __u32 byte_sz); 123LIBBPF_API int btf__add_datasec_var_info(struct btf *btf, int var_type_id, 124 __u32 offset, __u32 byte_sz); 125 126struct btf_dedup_opts { 127 unsigned int dedup_table_size; 128 bool dont_resolve_fwds; 129}; 130 131LIBBPF_API int btf__dedup(struct btf *btf, struct btf_ext *btf_ext, 132 const struct btf_dedup_opts *opts); 133 134struct btf_dump; 135 136struct btf_dump_opts { 137 void *ctx; 138}; 139 140typedef void (*btf_dump_printf_fn_t)(void *ctx, const char *fmt, va_list args); 141 142LIBBPF_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); 146LIBBPF_API void btf_dump__free(struct btf_dump *d); 147 148LIBBPF_API int btf_dump__dump_type(struct btf_dump *d, __u32 id); 149 150struct 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 size_t :0; 168}; 169#define btf_dump_emit_type_decl_opts__last_field strip_mods 170 171LIBBPF_API int 172btf_dump__emit_type_decl(struct btf_dump *d, __u32 id, 173 const struct btf_dump_emit_type_decl_opts *opts); 174 175/* 176 * A set of helpers for easier BTF types handling 177 */ 178static inline __u16 btf_kind(const struct btf_type *t) 179{ 180 return BTF_INFO_KIND(t->info); 181} 182 183static inline __u16 btf_vlen(const struct btf_type *t) 184{ 185 return BTF_INFO_VLEN(t->info); 186} 187 188static inline bool btf_kflag(const struct btf_type *t) 189{ 190 return BTF_INFO_KFLAG(t->info); 191} 192 193static inline bool btf_is_void(const struct btf_type *t) 194{ 195 return btf_kind(t) == BTF_KIND_UNKN; 196} 197 198static inline bool btf_is_int(const struct btf_type *t) 199{ 200 return btf_kind(t) == BTF_KIND_INT; 201} 202 203static inline bool btf_is_ptr(const struct btf_type *t) 204{ 205 return btf_kind(t) == BTF_KIND_PTR; 206} 207 208static inline bool btf_is_array(const struct btf_type *t) 209{ 210 return btf_kind(t) == BTF_KIND_ARRAY; 211} 212 213static inline bool btf_is_struct(const struct btf_type *t) 214{ 215 return btf_kind(t) == BTF_KIND_STRUCT; 216} 217 218static inline bool btf_is_union(const struct btf_type *t) 219{ 220 return btf_kind(t) == BTF_KIND_UNION; 221} 222 223static inline bool btf_is_composite(const struct btf_type *t) 224{ 225 __u16 kind = btf_kind(t); 226 227 return kind == BTF_KIND_STRUCT || kind == BTF_KIND_UNION; 228} 229 230static inline bool btf_is_enum(const struct btf_type *t) 231{ 232 return btf_kind(t) == BTF_KIND_ENUM; 233} 234 235static inline bool btf_is_fwd(const struct btf_type *t) 236{ 237 return btf_kind(t) == BTF_KIND_FWD; 238} 239 240static inline bool btf_is_typedef(const struct btf_type *t) 241{ 242 return btf_kind(t) == BTF_KIND_TYPEDEF; 243} 244 245static inline bool btf_is_volatile(const struct btf_type *t) 246{ 247 return btf_kind(t) == BTF_KIND_VOLATILE; 248} 249 250static inline bool btf_is_const(const struct btf_type *t) 251{ 252 return btf_kind(t) == BTF_KIND_CONST; 253} 254 255static inline bool btf_is_restrict(const struct btf_type *t) 256{ 257 return btf_kind(t) == BTF_KIND_RESTRICT; 258} 259 260static inline bool btf_is_mod(const struct btf_type *t) 261{ 262 __u16 kind = btf_kind(t); 263 264 return kind == BTF_KIND_VOLATILE || 265 kind == BTF_KIND_CONST || 266 kind == BTF_KIND_RESTRICT; 267} 268 269static inline bool btf_is_func(const struct btf_type *t) 270{ 271 return btf_kind(t) == BTF_KIND_FUNC; 272} 273 274static inline bool btf_is_func_proto(const struct btf_type *t) 275{ 276 return btf_kind(t) == BTF_KIND_FUNC_PROTO; 277} 278 279static inline bool btf_is_var(const struct btf_type *t) 280{ 281 return btf_kind(t) == BTF_KIND_VAR; 282} 283 284static inline bool btf_is_datasec(const struct btf_type *t) 285{ 286 return btf_kind(t) == BTF_KIND_DATASEC; 287} 288 289static inline __u8 btf_int_encoding(const struct btf_type *t) 290{ 291 return BTF_INT_ENCODING(*(__u32 *)(t + 1)); 292} 293 294static inline __u8 btf_int_offset(const struct btf_type *t) 295{ 296 return BTF_INT_OFFSET(*(__u32 *)(t + 1)); 297} 298 299static inline __u8 btf_int_bits(const struct btf_type *t) 300{ 301 return BTF_INT_BITS(*(__u32 *)(t + 1)); 302} 303 304static inline struct btf_array *btf_array(const struct btf_type *t) 305{ 306 return (struct btf_array *)(t + 1); 307} 308 309static inline struct btf_enum *btf_enum(const struct btf_type *t) 310{ 311 return (struct btf_enum *)(t + 1); 312} 313 314static inline struct btf_member *btf_members(const struct btf_type *t) 315{ 316 return (struct btf_member *)(t + 1); 317} 318 319/* Get bit offset of a member with specified index. */ 320static inline __u32 btf_member_bit_offset(const struct btf_type *t, 321 __u32 member_idx) 322{ 323 const struct btf_member *m = btf_members(t) + member_idx; 324 bool kflag = btf_kflag(t); 325 326 return kflag ? BTF_MEMBER_BIT_OFFSET(m->offset) : m->offset; 327} 328/* 329 * Get bitfield size of a member, assuming t is BTF_KIND_STRUCT or 330 * BTF_KIND_UNION. If member is not a bitfield, zero is returned. 331 */ 332static inline __u32 btf_member_bitfield_size(const struct btf_type *t, 333 __u32 member_idx) 334{ 335 const struct btf_member *m = btf_members(t) + member_idx; 336 bool kflag = btf_kflag(t); 337 338 return kflag ? BTF_MEMBER_BITFIELD_SIZE(m->offset) : 0; 339} 340 341static inline struct btf_param *btf_params(const struct btf_type *t) 342{ 343 return (struct btf_param *)(t + 1); 344} 345 346static inline struct btf_var *btf_var(const struct btf_type *t) 347{ 348 return (struct btf_var *)(t + 1); 349} 350 351static inline struct btf_var_secinfo * 352btf_var_secinfos(const struct btf_type *t) 353{ 354 return (struct btf_var_secinfo *)(t + 1); 355} 356 357#ifdef __cplusplus 358} /* extern "C" */ 359#endif 360 361#endif /* __LIBBPF_BTF_H */ 362