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 LIBBPF_API int btf__add_type(struct btf *btf, const struct btf *src_btf,
97 const struct btf_type *src_type);
98
99 LIBBPF_API int btf__add_int(struct btf *btf, const char *name, size_t byte_sz, int encoding);
100 LIBBPF_API int btf__add_float(struct btf *btf, const char *name, size_t byte_sz);
101 LIBBPF_API int btf__add_ptr(struct btf *btf, int ref_type_id);
102 LIBBPF_API int btf__add_array(struct btf *btf,
103 int index_type_id, int elem_type_id, __u32 nr_elems);
104 /* struct/union construction APIs */
105 LIBBPF_API int btf__add_struct(struct btf *btf, const char *name, __u32 sz);
106 LIBBPF_API int btf__add_union(struct btf *btf, const char *name, __u32 sz);
107 LIBBPF_API int btf__add_field(struct btf *btf, const char *name, int field_type_id,
108 __u32 bit_offset, __u32 bit_size);
109
110 /* enum construction APIs */
111 LIBBPF_API int btf__add_enum(struct btf *btf, const char *name, __u32 bytes_sz);
112 LIBBPF_API int btf__add_enum_value(struct btf *btf, const char *name, __s64 value);
113
114 enum btf_fwd_kind {
115 BTF_FWD_STRUCT = 0,
116 BTF_FWD_UNION = 1,
117 BTF_FWD_ENUM = 2,
118 };
119
120 LIBBPF_API int btf__add_fwd(struct btf *btf, const char *name, enum btf_fwd_kind fwd_kind);
121 LIBBPF_API int btf__add_typedef(struct btf *btf, const char *name, int ref_type_id);
122 LIBBPF_API int btf__add_volatile(struct btf *btf, int ref_type_id);
123 LIBBPF_API int btf__add_const(struct btf *btf, int ref_type_id);
124 LIBBPF_API int btf__add_restrict(struct btf *btf, int ref_type_id);
125
126 /* func and func_proto construction APIs */
127 LIBBPF_API int btf__add_func(struct btf *btf, const char *name,
128 enum btf_func_linkage linkage, int proto_type_id);
129 LIBBPF_API int btf__add_func_proto(struct btf *btf, int ret_type_id);
130 LIBBPF_API int btf__add_func_param(struct btf *btf, const char *name, int type_id);
131
132 /* var & datasec construction APIs */
133 LIBBPF_API int btf__add_var(struct btf *btf, const char *name, int linkage, int type_id);
134 LIBBPF_API int btf__add_datasec(struct btf *btf, const char *name, __u32 byte_sz);
135 LIBBPF_API int btf__add_datasec_var_info(struct btf *btf, int var_type_id,
136 __u32 offset, __u32 byte_sz);
137
138 struct btf_dedup_opts {
139 unsigned int dedup_table_size;
140 bool dont_resolve_fwds;
141 };
142
143 LIBBPF_API int btf__dedup(struct btf *btf, struct btf_ext *btf_ext,
144 const struct btf_dedup_opts *opts);
145
146 struct btf_dump;
147
148 struct btf_dump_opts {
149 void *ctx;
150 };
151
152 typedef void (*btf_dump_printf_fn_t)(void *ctx, const char *fmt, va_list args);
153
154 LIBBPF_API struct btf_dump *btf_dump__new(const struct btf *btf,
155 const struct btf_ext *btf_ext,
156 const struct btf_dump_opts *opts,
157 btf_dump_printf_fn_t printf_fn);
158 LIBBPF_API void btf_dump__free(struct btf_dump *d);
159
160 LIBBPF_API int btf_dump__dump_type(struct btf_dump *d, __u32 id);
161
162 struct btf_dump_emit_type_decl_opts {
163 /* size of this struct, for forward/backward compatiblity */
164 size_t sz;
165 /* optional field name for type declaration, e.g.:
166 * - struct my_struct <FNAME>
167 * - void (*<FNAME>)(int)
168 * - char (*<FNAME>)[123]
169 */
170 const char *field_name;
171 /* extra indentation level (in number of tabs) to emit for multi-line
172 * type declarations (e.g., anonymous struct); applies for lines
173 * starting from the second one (first line is assumed to have
174 * necessary indentation already
175 */
176 int indent_level;
177 /* strip all the const/volatile/restrict mods */
178 bool strip_mods;
179 size_t :0;
180 };
181 #define btf_dump_emit_type_decl_opts__last_field strip_mods
182
183 LIBBPF_API int
184 btf_dump__emit_type_decl(struct btf_dump *d, __u32 id,
185 const struct btf_dump_emit_type_decl_opts *opts);
186
187 /*
188 * A set of helpers for easier BTF types handling
189 */
btf_kind(const struct btf_type * t)190 static inline __u16 btf_kind(const struct btf_type *t)
191 {
192 return BTF_INFO_KIND(t->info);
193 }
194
btf_vlen(const struct btf_type * t)195 static inline __u16 btf_vlen(const struct btf_type *t)
196 {
197 return BTF_INFO_VLEN(t->info);
198 }
199
btf_kflag(const struct btf_type * t)200 static inline bool btf_kflag(const struct btf_type *t)
201 {
202 return BTF_INFO_KFLAG(t->info);
203 }
204
btf_is_void(const struct btf_type * t)205 static inline bool btf_is_void(const struct btf_type *t)
206 {
207 return btf_kind(t) == BTF_KIND_UNKN;
208 }
209
btf_is_int(const struct btf_type * t)210 static inline bool btf_is_int(const struct btf_type *t)
211 {
212 return btf_kind(t) == BTF_KIND_INT;
213 }
214
btf_is_ptr(const struct btf_type * t)215 static inline bool btf_is_ptr(const struct btf_type *t)
216 {
217 return btf_kind(t) == BTF_KIND_PTR;
218 }
219
btf_is_array(const struct btf_type * t)220 static inline bool btf_is_array(const struct btf_type *t)
221 {
222 return btf_kind(t) == BTF_KIND_ARRAY;
223 }
224
btf_is_struct(const struct btf_type * t)225 static inline bool btf_is_struct(const struct btf_type *t)
226 {
227 return btf_kind(t) == BTF_KIND_STRUCT;
228 }
229
btf_is_union(const struct btf_type * t)230 static inline bool btf_is_union(const struct btf_type *t)
231 {
232 return btf_kind(t) == BTF_KIND_UNION;
233 }
234
btf_is_composite(const struct btf_type * t)235 static inline bool btf_is_composite(const struct btf_type *t)
236 {
237 __u16 kind = btf_kind(t);
238
239 return kind == BTF_KIND_STRUCT || kind == BTF_KIND_UNION;
240 }
241
btf_is_enum(const struct btf_type * t)242 static inline bool btf_is_enum(const struct btf_type *t)
243 {
244 return btf_kind(t) == BTF_KIND_ENUM;
245 }
246
btf_is_fwd(const struct btf_type * t)247 static inline bool btf_is_fwd(const struct btf_type *t)
248 {
249 return btf_kind(t) == BTF_KIND_FWD;
250 }
251
btf_is_typedef(const struct btf_type * t)252 static inline bool btf_is_typedef(const struct btf_type *t)
253 {
254 return btf_kind(t) == BTF_KIND_TYPEDEF;
255 }
256
btf_is_volatile(const struct btf_type * t)257 static inline bool btf_is_volatile(const struct btf_type *t)
258 {
259 return btf_kind(t) == BTF_KIND_VOLATILE;
260 }
261
btf_is_const(const struct btf_type * t)262 static inline bool btf_is_const(const struct btf_type *t)
263 {
264 return btf_kind(t) == BTF_KIND_CONST;
265 }
266
btf_is_restrict(const struct btf_type * t)267 static inline bool btf_is_restrict(const struct btf_type *t)
268 {
269 return btf_kind(t) == BTF_KIND_RESTRICT;
270 }
271
btf_is_mod(const struct btf_type * t)272 static inline bool btf_is_mod(const struct btf_type *t)
273 {
274 __u16 kind = btf_kind(t);
275
276 return kind == BTF_KIND_VOLATILE ||
277 kind == BTF_KIND_CONST ||
278 kind == BTF_KIND_RESTRICT;
279 }
280
btf_is_func(const struct btf_type * t)281 static inline bool btf_is_func(const struct btf_type *t)
282 {
283 return btf_kind(t) == BTF_KIND_FUNC;
284 }
285
btf_is_func_proto(const struct btf_type * t)286 static inline bool btf_is_func_proto(const struct btf_type *t)
287 {
288 return btf_kind(t) == BTF_KIND_FUNC_PROTO;
289 }
290
btf_is_var(const struct btf_type * t)291 static inline bool btf_is_var(const struct btf_type *t)
292 {
293 return btf_kind(t) == BTF_KIND_VAR;
294 }
295
btf_is_datasec(const struct btf_type * t)296 static inline bool btf_is_datasec(const struct btf_type *t)
297 {
298 return btf_kind(t) == BTF_KIND_DATASEC;
299 }
300
btf_is_float(const struct btf_type * t)301 static inline bool btf_is_float(const struct btf_type *t)
302 {
303 return btf_kind(t) == BTF_KIND_FLOAT;
304 }
305
btf_int_encoding(const struct btf_type * t)306 static inline __u8 btf_int_encoding(const struct btf_type *t)
307 {
308 return BTF_INT_ENCODING(*(__u32 *)(t + 1));
309 }
310
btf_int_offset(const struct btf_type * t)311 static inline __u8 btf_int_offset(const struct btf_type *t)
312 {
313 return BTF_INT_OFFSET(*(__u32 *)(t + 1));
314 }
315
btf_int_bits(const struct btf_type * t)316 static inline __u8 btf_int_bits(const struct btf_type *t)
317 {
318 return BTF_INT_BITS(*(__u32 *)(t + 1));
319 }
320
btf_array(const struct btf_type * t)321 static inline struct btf_array *btf_array(const struct btf_type *t)
322 {
323 return (struct btf_array *)(t + 1);
324 }
325
btf_enum(const struct btf_type * t)326 static inline struct btf_enum *btf_enum(const struct btf_type *t)
327 {
328 return (struct btf_enum *)(t + 1);
329 }
330
btf_members(const struct btf_type * t)331 static inline struct btf_member *btf_members(const struct btf_type *t)
332 {
333 return (struct btf_member *)(t + 1);
334 }
335
336 /* Get bit offset of a member with specified index. */
btf_member_bit_offset(const struct btf_type * t,__u32 member_idx)337 static inline __u32 btf_member_bit_offset(const struct btf_type *t,
338 __u32 member_idx)
339 {
340 const struct btf_member *m = btf_members(t) + member_idx;
341 bool kflag = btf_kflag(t);
342
343 return kflag ? BTF_MEMBER_BIT_OFFSET(m->offset) : m->offset;
344 }
345 /*
346 * Get bitfield size of a member, assuming t is BTF_KIND_STRUCT or
347 * BTF_KIND_UNION. If member is not a bitfield, zero is returned.
348 */
btf_member_bitfield_size(const struct btf_type * t,__u32 member_idx)349 static inline __u32 btf_member_bitfield_size(const struct btf_type *t,
350 __u32 member_idx)
351 {
352 const struct btf_member *m = btf_members(t) + member_idx;
353 bool kflag = btf_kflag(t);
354
355 return kflag ? BTF_MEMBER_BITFIELD_SIZE(m->offset) : 0;
356 }
357
btf_params(const struct btf_type * t)358 static inline struct btf_param *btf_params(const struct btf_type *t)
359 {
360 return (struct btf_param *)(t + 1);
361 }
362
btf_var(const struct btf_type * t)363 static inline struct btf_var *btf_var(const struct btf_type *t)
364 {
365 return (struct btf_var *)(t + 1);
366 }
367
368 static inline struct btf_var_secinfo *
btf_var_secinfos(const struct btf_type * t)369 btf_var_secinfos(const struct btf_type *t)
370 {
371 return (struct btf_var_secinfo *)(t + 1);
372 }
373
374 #ifdef __cplusplus
375 } /* extern "C" */
376 #endif
377
378 #endif /* __LIBBPF_BTF_H */
379