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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 <linux/btf.h>
9#include <linux/types.h>
10
11#include "libbpf_common.h"
12
13#ifdef __cplusplus
14extern "C" {
15#endif
16
17#define BTF_ELF_SEC ".BTF"
18#define BTF_EXT_ELF_SEC ".BTF.ext"
19#define MAPS_ELF_SEC ".maps"
20
21struct btf;
22struct btf_ext;
23struct btf_type;
24
25struct bpf_object;
26
27/*
28 * The .BTF.ext ELF section layout defined as
29 * struct btf_ext_header
30 * func_info subsection
31 *
32 * The func_info subsection layout:
33 * record size for struct bpf_func_info in the func_info subsection
34 * struct btf_sec_func_info for section #1
35 * a list of bpf_func_info records for section #1
36 * where struct bpf_func_info mimics one in include/uapi/linux/bpf.h
37 * but may not be identical
38 * struct btf_sec_func_info for section #2
39 * a list of bpf_func_info records for section #2
40 * ......
41 *
42 * Note that the bpf_func_info record size in .BTF.ext may not
43 * be the same as the one defined in include/uapi/linux/bpf.h.
44 * The loader should ensure that record_size meets minimum
45 * requirement and pass the record as is to the kernel. The
46 * kernel will handle the func_info properly based on its contents.
47 */
48struct btf_ext_header {
49 __u16 magic;
50 __u8 version;
51 __u8 flags;
52 __u32 hdr_len;
53
54 /* All offsets are in bytes relative to the end of this header */
55 __u32 func_info_off;
56 __u32 func_info_len;
57 __u32 line_info_off;
58 __u32 line_info_len;
59
60 /* optional part of .BTF.ext header */
61 __u32 field_reloc_off;
62 __u32 field_reloc_len;
63};
64
65LIBBPF_API void btf__free(struct btf *btf);
66LIBBPF_API struct btf *btf__new(const void *data, __u32 size);
67LIBBPF_API struct btf *btf__parse(const char *path, struct btf_ext **btf_ext);
68LIBBPF_API struct btf *btf__parse_elf(const char *path, struct btf_ext **btf_ext);
69LIBBPF_API struct btf *btf__parse_raw(const char *path);
70LIBBPF_API int btf__finalize_data(struct bpf_object *obj, struct btf *btf);
71LIBBPF_API int btf__load(struct btf *btf);
72LIBBPF_API __s32 btf__find_by_name(const struct btf *btf,
73 const char *type_name);
74LIBBPF_API __s32 btf__find_by_name_kind(const struct btf *btf,
75 const char *type_name, __u32 kind);
76LIBBPF_API __u32 btf__get_nr_types(const struct btf *btf);
77LIBBPF_API const struct btf_type *btf__type_by_id(const struct btf *btf,
78 __u32 id);
79LIBBPF_API size_t btf__pointer_size(const struct btf *btf);
80LIBBPF_API int btf__set_pointer_size(struct btf *btf, size_t ptr_sz);
81LIBBPF_API __s64 btf__resolve_size(const struct btf *btf, __u32 type_id);
82LIBBPF_API int btf__resolve_type(const struct btf *btf, __u32 type_id);
83LIBBPF_API int btf__align_of(const struct btf *btf, __u32 id);
84LIBBPF_API int btf__fd(const struct btf *btf);
85LIBBPF_API void btf__set_fd(struct btf *btf, int fd);
86LIBBPF_API const void *btf__get_raw_data(const struct btf *btf, __u32 *size);
87LIBBPF_API const char *btf__name_by_offset(const struct btf *btf, __u32 offset);
88LIBBPF_API int btf__get_from_id(__u32 id, struct btf **btf);
89LIBBPF_API int btf__get_map_kv_tids(const struct btf *btf, const char *map_name,
90 __u32 expected_key_size,
91 __u32 expected_value_size,
92 __u32 *key_type_id, __u32 *value_type_id);
93
94LIBBPF_API struct btf_ext *btf_ext__new(__u8 *data, __u32 size);
95LIBBPF_API void btf_ext__free(struct btf_ext *btf_ext);
96LIBBPF_API const void *btf_ext__get_raw_data(const struct btf_ext *btf_ext,
97 __u32 *size);
98LIBBPF_API int btf_ext__reloc_func_info(const struct btf *btf,
99 const struct btf_ext *btf_ext,
100 const char *sec_name, __u32 insns_cnt,
101 void **func_info, __u32 *cnt);
102LIBBPF_API int btf_ext__reloc_line_info(const struct btf *btf,
103 const struct btf_ext *btf_ext,
104 const char *sec_name, __u32 insns_cnt,
105 void **line_info, __u32 *cnt);
106LIBBPF_API __u32 btf_ext__func_info_rec_size(const struct btf_ext *btf_ext);
107LIBBPF_API __u32 btf_ext__line_info_rec_size(const struct btf_ext *btf_ext);
108
109LIBBPF_API struct btf *libbpf_find_kernel_btf(void);
110
111struct btf_dedup_opts {
112 unsigned int dedup_table_size;
113 bool dont_resolve_fwds;
114};
115
116LIBBPF_API int btf__dedup(struct btf *btf, struct btf_ext *btf_ext,
117 const struct btf_dedup_opts *opts);
118
119struct btf_dump;
120
121struct btf_dump_opts {
122 void *ctx;
123};
124
125typedef void (*btf_dump_printf_fn_t)(void *ctx, const char *fmt, va_list args);
126
127LIBBPF_API struct btf_dump *btf_dump__new(const struct btf *btf,
128 const struct btf_ext *btf_ext,
129 const struct btf_dump_opts *opts,
130 btf_dump_printf_fn_t printf_fn);
131LIBBPF_API void btf_dump__free(struct btf_dump *d);
132
133LIBBPF_API int btf_dump__dump_type(struct btf_dump *d, __u32 id);
134
135struct btf_dump_emit_type_decl_opts {
136 /* size of this struct, for forward/backward compatiblity */
137 size_t sz;
138 /* optional field name for type declaration, e.g.:
139 * - struct my_struct <FNAME>
140 * - void (*<FNAME>)(int)
141 * - char (*<FNAME>)[123]
142 */
143 const char *field_name;
144 /* extra indentation level (in number of tabs) to emit for multi-line
145 * type declarations (e.g., anonymous struct); applies for lines
146 * starting from the second one (first line is assumed to have
147 * necessary indentation already
148 */
149 int indent_level;
150 /* strip all the const/volatile/restrict mods */
151 bool strip_mods;
152};
153#define btf_dump_emit_type_decl_opts__last_field strip_mods
154
155LIBBPF_API int
156btf_dump__emit_type_decl(struct btf_dump *d, __u32 id,
157 const struct btf_dump_emit_type_decl_opts *opts);
158
159/*
160 * A set of helpers for easier BTF types handling
161 */
162static inline __u16 btf_kind(const struct btf_type *t)
163{
164 return BTF_INFO_KIND(t->info);
165}
166
167static inline __u16 btf_vlen(const struct btf_type *t)
168{
169 return BTF_INFO_VLEN(t->info);
170}
171
172static inline bool btf_kflag(const struct btf_type *t)
173{
174 return BTF_INFO_KFLAG(t->info);
175}
176
177static inline bool btf_is_void(const struct btf_type *t)
178{
179 return btf_kind(t) == BTF_KIND_UNKN;
180}
181
182static inline bool btf_is_int(const struct btf_type *t)
183{
184 return btf_kind(t) == BTF_KIND_INT;
185}
186
187static inline bool btf_is_ptr(const struct btf_type *t)
188{
189 return btf_kind(t) == BTF_KIND_PTR;
190}
191
192static inline bool btf_is_array(const struct btf_type *t)
193{
194 return btf_kind(t) == BTF_KIND_ARRAY;
195}
196
197static inline bool btf_is_struct(const struct btf_type *t)
198{
199 return btf_kind(t) == BTF_KIND_STRUCT;
200}
201
202static inline bool btf_is_union(const struct btf_type *t)
203{
204 return btf_kind(t) == BTF_KIND_UNION;
205}
206
207static inline bool btf_is_composite(const struct btf_type *t)
208{
209 __u16 kind = btf_kind(t);
210
211 return kind == BTF_KIND_STRUCT || kind == BTF_KIND_UNION;
212}
213
214static inline bool btf_is_enum(const struct btf_type *t)
215{
216 return btf_kind(t) == BTF_KIND_ENUM;
217}
218
219static inline bool btf_is_fwd(const struct btf_type *t)
220{
221 return btf_kind(t) == BTF_KIND_FWD;
222}
223
224static inline bool btf_is_typedef(const struct btf_type *t)
225{
226 return btf_kind(t) == BTF_KIND_TYPEDEF;
227}
228
229static inline bool btf_is_volatile(const struct btf_type *t)
230{
231 return btf_kind(t) == BTF_KIND_VOLATILE;
232}
233
234static inline bool btf_is_const(const struct btf_type *t)
235{
236 return btf_kind(t) == BTF_KIND_CONST;
237}
238
239static inline bool btf_is_restrict(const struct btf_type *t)
240{
241 return btf_kind(t) == BTF_KIND_RESTRICT;
242}
243
244static inline bool btf_is_mod(const struct btf_type *t)
245{
246 __u16 kind = btf_kind(t);
247
248 return kind == BTF_KIND_VOLATILE ||
249 kind == BTF_KIND_CONST ||
250 kind == BTF_KIND_RESTRICT;
251}
252
253static inline bool btf_is_func(const struct btf_type *t)
254{
255 return btf_kind(t) == BTF_KIND_FUNC;
256}
257
258static inline bool btf_is_func_proto(const struct btf_type *t)
259{
260 return btf_kind(t) == BTF_KIND_FUNC_PROTO;
261}
262
263static inline bool btf_is_var(const struct btf_type *t)
264{
265 return btf_kind(t) == BTF_KIND_VAR;
266}
267
268static inline bool btf_is_datasec(const struct btf_type *t)
269{
270 return btf_kind(t) == BTF_KIND_DATASEC;
271}
272
273static inline __u8 btf_int_encoding(const struct btf_type *t)
274{
275 return BTF_INT_ENCODING(*(__u32 *)(t + 1));
276}
277
278static inline __u8 btf_int_offset(const struct btf_type *t)
279{
280 return BTF_INT_OFFSET(*(__u32 *)(t + 1));
281}
282
283static inline __u8 btf_int_bits(const struct btf_type *t)
284{
285 return BTF_INT_BITS(*(__u32 *)(t + 1));
286}
287
288static inline struct btf_array *btf_array(const struct btf_type *t)
289{
290 return (struct btf_array *)(t + 1);
291}
292
293static inline struct btf_enum *btf_enum(const struct btf_type *t)
294{
295 return (struct btf_enum *)(t + 1);
296}
297
298static inline struct btf_member *btf_members(const struct btf_type *t)
299{
300 return (struct btf_member *)(t + 1);
301}
302
303/* Get bit offset of a member with specified index. */
304static inline __u32 btf_member_bit_offset(const struct btf_type *t,
305 __u32 member_idx)
306{
307 const struct btf_member *m = btf_members(t) + member_idx;
308 bool kflag = btf_kflag(t);
309
310 return kflag ? BTF_MEMBER_BIT_OFFSET(m->offset) : m->offset;
311}
312/*
313 * Get bitfield size of a member, assuming t is BTF_KIND_STRUCT or
314 * BTF_KIND_UNION. If member is not a bitfield, zero is returned.
315 */
316static inline __u32 btf_member_bitfield_size(const struct btf_type *t,
317 __u32 member_idx)
318{
319 const struct btf_member *m = btf_members(t) + member_idx;
320 bool kflag = btf_kflag(t);
321
322 return kflag ? BTF_MEMBER_BITFIELD_SIZE(m->offset) : 0;
323}
324
325static inline struct btf_param *btf_params(const struct btf_type *t)
326{
327 return (struct btf_param *)(t + 1);
328}
329
330static inline struct btf_var *btf_var(const struct btf_type *t)
331{
332 return (struct btf_var *)(t + 1);
333}
334
335static inline struct btf_var_secinfo *
336btf_var_secinfos(const struct btf_type *t)
337{
338 return (struct btf_var_secinfo *)(t + 1);
339}
340
341#ifdef __cplusplus
342} /* extern "C" */
343#endif
344
345#endif /* __LIBBPF_BTF_H */
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 <linux/btf.h>
9#include <linux/types.h>
10
11#ifdef __cplusplus
12extern "C" {
13#endif
14
15#ifndef LIBBPF_API
16#define LIBBPF_API __attribute__((visibility("default")))
17#endif
18
19#define BTF_ELF_SEC ".BTF"
20#define BTF_EXT_ELF_SEC ".BTF.ext"
21#define MAPS_ELF_SEC ".maps"
22
23struct btf;
24struct btf_ext;
25struct btf_type;
26
27struct bpf_object;
28
29/*
30 * The .BTF.ext ELF section layout defined as
31 * struct btf_ext_header
32 * func_info subsection
33 *
34 * The func_info subsection layout:
35 * record size for struct bpf_func_info in the func_info subsection
36 * struct btf_sec_func_info for section #1
37 * a list of bpf_func_info records for section #1
38 * where struct bpf_func_info mimics one in include/uapi/linux/bpf.h
39 * but may not be identical
40 * struct btf_sec_func_info for section #2
41 * a list of bpf_func_info records for section #2
42 * ......
43 *
44 * Note that the bpf_func_info record size in .BTF.ext may not
45 * be the same as the one defined in include/uapi/linux/bpf.h.
46 * The loader should ensure that record_size meets minimum
47 * requirement and pass the record as is to the kernel. The
48 * kernel will handle the func_info properly based on its contents.
49 */
50struct btf_ext_header {
51 __u16 magic;
52 __u8 version;
53 __u8 flags;
54 __u32 hdr_len;
55
56 /* All offsets are in bytes relative to the end of this header */
57 __u32 func_info_off;
58 __u32 func_info_len;
59 __u32 line_info_off;
60 __u32 line_info_len;
61
62 /* optional part of .BTF.ext header */
63 __u32 offset_reloc_off;
64 __u32 offset_reloc_len;
65};
66
67LIBBPF_API void btf__free(struct btf *btf);
68LIBBPF_API struct btf *btf__new(__u8 *data, __u32 size);
69LIBBPF_API struct btf *btf__parse_elf(const char *path,
70 struct btf_ext **btf_ext);
71LIBBPF_API int btf__finalize_data(struct bpf_object *obj, struct btf *btf);
72LIBBPF_API int btf__load(struct btf *btf);
73LIBBPF_API __s32 btf__find_by_name(const struct btf *btf,
74 const char *type_name);
75LIBBPF_API __u32 btf__get_nr_types(const struct btf *btf);
76LIBBPF_API const struct btf_type *btf__type_by_id(const struct btf *btf,
77 __u32 id);
78LIBBPF_API __s64 btf__resolve_size(const struct btf *btf, __u32 type_id);
79LIBBPF_API int btf__resolve_type(const struct btf *btf, __u32 type_id);
80LIBBPF_API int btf__fd(const struct btf *btf);
81LIBBPF_API const void *btf__get_raw_data(const struct btf *btf, __u32 *size);
82LIBBPF_API const char *btf__name_by_offset(const struct btf *btf, __u32 offset);
83LIBBPF_API int btf__get_from_id(__u32 id, struct btf **btf);
84LIBBPF_API int btf__get_map_kv_tids(const struct btf *btf, const char *map_name,
85 __u32 expected_key_size,
86 __u32 expected_value_size,
87 __u32 *key_type_id, __u32 *value_type_id);
88
89LIBBPF_API struct btf_ext *btf_ext__new(__u8 *data, __u32 size);
90LIBBPF_API void btf_ext__free(struct btf_ext *btf_ext);
91LIBBPF_API const void *btf_ext__get_raw_data(const struct btf_ext *btf_ext,
92 __u32 *size);
93LIBBPF_API int btf_ext__reloc_func_info(const struct btf *btf,
94 const struct btf_ext *btf_ext,
95 const char *sec_name, __u32 insns_cnt,
96 void **func_info, __u32 *cnt);
97LIBBPF_API int btf_ext__reloc_line_info(const struct btf *btf,
98 const struct btf_ext *btf_ext,
99 const char *sec_name, __u32 insns_cnt,
100 void **line_info, __u32 *cnt);
101LIBBPF_API __u32 btf_ext__func_info_rec_size(const struct btf_ext *btf_ext);
102LIBBPF_API __u32 btf_ext__line_info_rec_size(const struct btf_ext *btf_ext);
103
104struct btf_dedup_opts {
105 unsigned int dedup_table_size;
106 bool dont_resolve_fwds;
107};
108
109LIBBPF_API int btf__dedup(struct btf *btf, struct btf_ext *btf_ext,
110 const struct btf_dedup_opts *opts);
111
112struct btf_dump;
113
114struct btf_dump_opts {
115 void *ctx;
116};
117
118typedef void (*btf_dump_printf_fn_t)(void *ctx, const char *fmt, va_list args);
119
120LIBBPF_API struct btf_dump *btf_dump__new(const struct btf *btf,
121 const struct btf_ext *btf_ext,
122 const struct btf_dump_opts *opts,
123 btf_dump_printf_fn_t printf_fn);
124LIBBPF_API void btf_dump__free(struct btf_dump *d);
125
126LIBBPF_API int btf_dump__dump_type(struct btf_dump *d, __u32 id);
127
128/*
129 * A set of helpers for easier BTF types handling
130 */
131static inline __u16 btf_kind(const struct btf_type *t)
132{
133 return BTF_INFO_KIND(t->info);
134}
135
136static inline __u16 btf_vlen(const struct btf_type *t)
137{
138 return BTF_INFO_VLEN(t->info);
139}
140
141static inline bool btf_kflag(const struct btf_type *t)
142{
143 return BTF_INFO_KFLAG(t->info);
144}
145
146static inline bool btf_is_int(const struct btf_type *t)
147{
148 return btf_kind(t) == BTF_KIND_INT;
149}
150
151static inline bool btf_is_ptr(const struct btf_type *t)
152{
153 return btf_kind(t) == BTF_KIND_PTR;
154}
155
156static inline bool btf_is_array(const struct btf_type *t)
157{
158 return btf_kind(t) == BTF_KIND_ARRAY;
159}
160
161static inline bool btf_is_struct(const struct btf_type *t)
162{
163 return btf_kind(t) == BTF_KIND_STRUCT;
164}
165
166static inline bool btf_is_union(const struct btf_type *t)
167{
168 return btf_kind(t) == BTF_KIND_UNION;
169}
170
171static inline bool btf_is_composite(const struct btf_type *t)
172{
173 __u16 kind = btf_kind(t);
174
175 return kind == BTF_KIND_STRUCT || kind == BTF_KIND_UNION;
176}
177
178static inline bool btf_is_enum(const struct btf_type *t)
179{
180 return btf_kind(t) == BTF_KIND_ENUM;
181}
182
183static inline bool btf_is_fwd(const struct btf_type *t)
184{
185 return btf_kind(t) == BTF_KIND_FWD;
186}
187
188static inline bool btf_is_typedef(const struct btf_type *t)
189{
190 return btf_kind(t) == BTF_KIND_TYPEDEF;
191}
192
193static inline bool btf_is_volatile(const struct btf_type *t)
194{
195 return btf_kind(t) == BTF_KIND_VOLATILE;
196}
197
198static inline bool btf_is_const(const struct btf_type *t)
199{
200 return btf_kind(t) == BTF_KIND_CONST;
201}
202
203static inline bool btf_is_restrict(const struct btf_type *t)
204{
205 return btf_kind(t) == BTF_KIND_RESTRICT;
206}
207
208static inline bool btf_is_mod(const struct btf_type *t)
209{
210 __u16 kind = btf_kind(t);
211
212 return kind == BTF_KIND_VOLATILE ||
213 kind == BTF_KIND_CONST ||
214 kind == BTF_KIND_RESTRICT;
215}
216
217static inline bool btf_is_func(const struct btf_type *t)
218{
219 return btf_kind(t) == BTF_KIND_FUNC;
220}
221
222static inline bool btf_is_func_proto(const struct btf_type *t)
223{
224 return btf_kind(t) == BTF_KIND_FUNC_PROTO;
225}
226
227static inline bool btf_is_var(const struct btf_type *t)
228{
229 return btf_kind(t) == BTF_KIND_VAR;
230}
231
232static inline bool btf_is_datasec(const struct btf_type *t)
233{
234 return btf_kind(t) == BTF_KIND_DATASEC;
235}
236
237static inline __u8 btf_int_encoding(const struct btf_type *t)
238{
239 return BTF_INT_ENCODING(*(__u32 *)(t + 1));
240}
241
242static inline __u8 btf_int_offset(const struct btf_type *t)
243{
244 return BTF_INT_OFFSET(*(__u32 *)(t + 1));
245}
246
247static inline __u8 btf_int_bits(const struct btf_type *t)
248{
249 return BTF_INT_BITS(*(__u32 *)(t + 1));
250}
251
252static inline struct btf_array *btf_array(const struct btf_type *t)
253{
254 return (struct btf_array *)(t + 1);
255}
256
257static inline struct btf_enum *btf_enum(const struct btf_type *t)
258{
259 return (struct btf_enum *)(t + 1);
260}
261
262static inline struct btf_member *btf_members(const struct btf_type *t)
263{
264 return (struct btf_member *)(t + 1);
265}
266
267/* Get bit offset of a member with specified index. */
268static inline __u32 btf_member_bit_offset(const struct btf_type *t,
269 __u32 member_idx)
270{
271 const struct btf_member *m = btf_members(t) + member_idx;
272 bool kflag = btf_kflag(t);
273
274 return kflag ? BTF_MEMBER_BIT_OFFSET(m->offset) : m->offset;
275}
276/*
277 * Get bitfield size of a member, assuming t is BTF_KIND_STRUCT or
278 * BTF_KIND_UNION. If member is not a bitfield, zero is returned.
279 */
280static inline __u32 btf_member_bitfield_size(const struct btf_type *t,
281 __u32 member_idx)
282{
283 const struct btf_member *m = btf_members(t) + member_idx;
284 bool kflag = btf_kflag(t);
285
286 return kflag ? BTF_MEMBER_BITFIELD_SIZE(m->offset) : 0;
287}
288
289static inline struct btf_param *btf_params(const struct btf_type *t)
290{
291 return (struct btf_param *)(t + 1);
292}
293
294static inline struct btf_var *btf_var(const struct btf_type *t)
295{
296 return (struct btf_var *)(t + 1);
297}
298
299static inline struct btf_var_secinfo *
300btf_var_secinfos(const struct btf_type *t)
301{
302 return (struct btf_var_secinfo *)(t + 1);
303}
304
305#ifdef __cplusplus
306} /* extern "C" */
307#endif
308
309#endif /* __LIBBPF_BTF_H */