1 /* SPDX-License-Identifier: (LGPL-2.1 OR BSD-2-Clause) */
2 /* Copyright (c) 2018 Facebook */
3 /*! \file */
4
5 #ifndef __LIBBPF_BTF_H
6 #define __LIBBPF_BTF_H
7
8 #include <stdarg.h>
9 #include <stdbool.h>
10 #include <linux/btf.h>
11 #include <linux/types.h>
12
13 #include "libbpf_common.h"
14
15 #ifdef __cplusplus
16 extern "C" {
17 #endif
18
19 #define BTF_ELF_SEC ".BTF"
20 #define BTF_EXT_ELF_SEC ".BTF.ext"
21 #define BTF_BASE_ELF_SEC ".BTF.base"
22 #define MAPS_ELF_SEC ".maps"
23
24 struct btf;
25 struct btf_ext;
26 struct btf_type;
27
28 struct bpf_object;
29
30 enum btf_endianness {
31 BTF_LITTLE_ENDIAN = 0,
32 BTF_BIG_ENDIAN = 1,
33 };
34
35 /**
36 * @brief **btf__free()** frees all data of a BTF object
37 * @param btf BTF object to free
38 */
39 LIBBPF_API void btf__free(struct btf *btf);
40
41 /**
42 * @brief **btf__new()** creates a new instance of a BTF object from the raw
43 * bytes of an ELF's BTF section
44 * @param data raw bytes
45 * @param size number of bytes passed in `data`
46 * @return new BTF object instance which has to be eventually freed with
47 * **btf__free()**
48 *
49 * On error, error-code-encoded-as-pointer is returned, not a NULL. To extract
50 * error code from such a pointer `libbpf_get_error()` should be used. If
51 * `libbpf_set_strict_mode(LIBBPF_STRICT_CLEAN_PTRS)` is enabled, NULL is
52 * returned on error instead. In both cases thread-local `errno` variable is
53 * always set to error code as well.
54 */
55 LIBBPF_API struct btf *btf__new(const void *data, __u32 size);
56
57 /**
58 * @brief **btf__new_split()** create a new instance of a BTF object from the
59 * provided raw data bytes. It takes another BTF instance, **base_btf**, which
60 * serves as a base BTF, which is extended by types in a newly created BTF
61 * instance
62 * @param data raw bytes
63 * @param size length of raw bytes
64 * @param base_btf the base BTF object
65 * @return new BTF object instance which has to be eventually freed with
66 * **btf__free()**
67 *
68 * If *base_btf* is NULL, `btf__new_split()` is equivalent to `btf__new()` and
69 * creates non-split BTF.
70 *
71 * On error, error-code-encoded-as-pointer is returned, not a NULL. To extract
72 * error code from such a pointer `libbpf_get_error()` should be used. If
73 * `libbpf_set_strict_mode(LIBBPF_STRICT_CLEAN_PTRS)` is enabled, NULL is
74 * returned on error instead. In both cases thread-local `errno` variable is
75 * always set to error code as well.
76 */
77 LIBBPF_API struct btf *btf__new_split(const void *data, __u32 size, struct btf *base_btf);
78
79 /**
80 * @brief **btf__new_empty()** creates an empty BTF object. Use
81 * `btf__add_*()` to populate such BTF object.
82 * @return new BTF object instance which has to be eventually freed with
83 * **btf__free()**
84 *
85 * On error, error-code-encoded-as-pointer is returned, not a NULL. To extract
86 * error code from such a pointer `libbpf_get_error()` should be used. If
87 * `libbpf_set_strict_mode(LIBBPF_STRICT_CLEAN_PTRS)` is enabled, NULL is
88 * returned on error instead. In both cases thread-local `errno` variable is
89 * always set to error code as well.
90 */
91 LIBBPF_API struct btf *btf__new_empty(void);
92
93 /**
94 * @brief **btf__new_empty_split()** creates an unpopulated BTF object from an
95 * ELF BTF section except with a base BTF on top of which split BTF should be
96 * based
97 * @param base_btf base BTF object
98 * @return new BTF object instance which has to be eventually freed with
99 * **btf__free()**
100 *
101 * If *base_btf* is NULL, `btf__new_empty_split()` is equivalent to
102 * `btf__new_empty()` and creates non-split BTF.
103 *
104 * On error, error-code-encoded-as-pointer is returned, not a NULL. To extract
105 * error code from such a pointer `libbpf_get_error()` should be used. If
106 * `libbpf_set_strict_mode(LIBBPF_STRICT_CLEAN_PTRS)` is enabled, NULL is
107 * returned on error instead. In both cases thread-local `errno` variable is
108 * always set to error code as well.
109 */
110 LIBBPF_API struct btf *btf__new_empty_split(struct btf *base_btf);
111
112 struct btf_new_opts {
113 size_t sz;
114 struct btf *base_btf; /* optional base BTF */
115 bool add_layout; /* add BTF layout information */
116 size_t:0;
117 };
118 #define btf_new_opts__last_field add_layout
119
120 /**
121 * @brief **btf__new_empty_opts()** creates an unpopulated BTF object with
122 * optional *base_btf* and BTF kind layout description if *add_layout*
123 * is set
124 * @return new BTF object instance which has to be eventually freed with
125 * **btf__free()**
126 *
127 * On error, NULL is returned and the thread-local `errno` variable is
128 * set to the error code.
129 */
130 LIBBPF_API struct btf *btf__new_empty_opts(struct btf_new_opts *opts);
131
132 /**
133 * @brief **btf__distill_base()** creates new versions of the split BTF
134 * *src_btf* and its base BTF. The new base BTF will only contain the types
135 * needed to improve robustness of the split BTF to small changes in base BTF.
136 * When that split BTF is loaded against a (possibly changed) base, this
137 * distilled base BTF will help update references to that (possibly changed)
138 * base BTF.
139 * @param src_btf source split BTF object
140 * @param new_base_btf pointer to where the new base BTF object pointer will be stored
141 * @param new_split_btf pointer to where the new split BTF object pointer will be stored
142 * @return 0 on success; negative error code, otherwise
143 *
144 * Both the new split and its associated new base BTF must be freed by
145 * the caller.
146 *
147 * If successful, 0 is returned and **new_base_btf** and **new_split_btf**
148 * will point at new base/split BTF. Both the new split and its associated
149 * new base BTF must be freed by the caller.
150 *
151 * A negative value is returned on error and the thread-local `errno` variable
152 * is set to the error code as well.
153 */
154 LIBBPF_API int btf__distill_base(const struct btf *src_btf, struct btf **new_base_btf,
155 struct btf **new_split_btf);
156
157 LIBBPF_API struct btf *btf__parse(const char *path, struct btf_ext **btf_ext);
158 LIBBPF_API struct btf *btf__parse_split(const char *path, struct btf *base_btf);
159 LIBBPF_API struct btf *btf__parse_elf(const char *path, struct btf_ext **btf_ext);
160 LIBBPF_API struct btf *btf__parse_elf_split(const char *path, struct btf *base_btf);
161 LIBBPF_API struct btf *btf__parse_raw(const char *path);
162 LIBBPF_API struct btf *btf__parse_raw_split(const char *path, struct btf *base_btf);
163
164 LIBBPF_API struct btf *btf__load_vmlinux_btf(void);
165 LIBBPF_API struct btf *btf__load_module_btf(const char *module_name, struct btf *vmlinux_btf);
166
167 LIBBPF_API struct btf *btf__load_from_kernel_by_id(__u32 id);
168 LIBBPF_API struct btf *btf__load_from_kernel_by_id_split(__u32 id, struct btf *base_btf);
169
170 LIBBPF_API int btf__load_into_kernel(struct btf *btf);
171 LIBBPF_API __s32 btf__find_by_name(const struct btf *btf,
172 const char *type_name);
173 LIBBPF_API __s32 btf__find_by_name_kind(const struct btf *btf,
174 const char *type_name, __u32 kind);
175 LIBBPF_API __s32 btf__find_by_name_kind_own(const struct btf *btf,
176 const char *type_name, __u32 kind);
177 LIBBPF_API __u32 btf__type_cnt(const struct btf *btf);
178 LIBBPF_API const struct btf *btf__base_btf(const struct btf *btf);
179 LIBBPF_API const struct btf_type *btf__type_by_id(const struct btf *btf,
180 __u32 id);
181 LIBBPF_API size_t btf__pointer_size(const struct btf *btf);
182 LIBBPF_API int btf__set_pointer_size(struct btf *btf, size_t ptr_sz);
183 LIBBPF_API enum btf_endianness btf__endianness(const struct btf *btf);
184 LIBBPF_API int btf__set_endianness(struct btf *btf, enum btf_endianness endian);
185 LIBBPF_API __s64 btf__resolve_size(const struct btf *btf, __u32 type_id);
186 LIBBPF_API int btf__resolve_type(const struct btf *btf, __u32 type_id);
187 LIBBPF_API int btf__align_of(const struct btf *btf, __u32 id);
188 LIBBPF_API int btf__fd(const struct btf *btf);
189 LIBBPF_API void btf__set_fd(struct btf *btf, int fd);
190 LIBBPF_API const void *btf__raw_data(const struct btf *btf, __u32 *size);
191 LIBBPF_API const char *btf__name_by_offset(const struct btf *btf, __u32 offset);
192 LIBBPF_API const char *btf__str_by_offset(const struct btf *btf, __u32 offset);
193
194 LIBBPF_API struct btf_ext *btf_ext__new(const __u8 *data, __u32 size);
195 LIBBPF_API void btf_ext__free(struct btf_ext *btf_ext);
196 LIBBPF_API const void *btf_ext__raw_data(const struct btf_ext *btf_ext, __u32 *size);
197 LIBBPF_API enum btf_endianness btf_ext__endianness(const struct btf_ext *btf_ext);
198 LIBBPF_API int btf_ext__set_endianness(struct btf_ext *btf_ext,
199 enum btf_endianness endian);
200
201 LIBBPF_API int btf__find_str(struct btf *btf, const char *s);
202 LIBBPF_API int btf__add_str(struct btf *btf, const char *s);
203 LIBBPF_API int btf__add_type(struct btf *btf, const struct btf *src_btf,
204 const struct btf_type *src_type);
205 /**
206 * @brief **btf__add_btf()** appends all the BTF types from *src_btf* into *btf*
207 * @param btf BTF object which all the BTF types and strings are added to
208 * @param src_btf BTF object which all BTF types and referenced strings are copied from
209 * @return BTF type ID of the first appended BTF type, or negative error code
210 *
211 * **btf__add_btf()** can be used to simply and efficiently append the entire
212 * contents of one BTF object to another one. All the BTF type data is copied
213 * over, all referenced type IDs are adjusted by adding a necessary ID offset.
214 * Only strings referenced from BTF types are copied over and deduplicated, so
215 * if there were some unused strings in *src_btf*, those won't be copied over,
216 * which is consistent with the general string deduplication semantics of BTF
217 * writing APIs.
218 *
219 * If any error is encountered during this process, the contents of *btf* is
220 * left intact, which means that **btf__add_btf()** follows the transactional
221 * semantics and the operation as a whole is all-or-nothing.
222 *
223 * *src_btf* has to be non-split BTF, as of now copying types from split BTF
224 * is not supported and will result in -ENOTSUP error code returned.
225 */
226 LIBBPF_API int btf__add_btf(struct btf *btf, const struct btf *src_btf);
227
228 LIBBPF_API int btf__add_int(struct btf *btf, const char *name, size_t byte_sz, int encoding);
229 LIBBPF_API int btf__add_float(struct btf *btf, const char *name, size_t byte_sz);
230 LIBBPF_API int btf__add_ptr(struct btf *btf, int ref_type_id);
231 LIBBPF_API int btf__add_array(struct btf *btf,
232 int index_type_id, int elem_type_id, __u32 nr_elems);
233 /* struct/union construction APIs */
234 LIBBPF_API int btf__add_struct(struct btf *btf, const char *name, __u32 sz);
235 LIBBPF_API int btf__add_union(struct btf *btf, const char *name, __u32 sz);
236 LIBBPF_API int btf__add_field(struct btf *btf, const char *name, int field_type_id,
237 __u32 bit_offset, __u32 bit_size);
238
239 /* enum construction APIs */
240 LIBBPF_API int btf__add_enum(struct btf *btf, const char *name, __u32 bytes_sz);
241 LIBBPF_API int btf__add_enum_value(struct btf *btf, const char *name, __s64 value);
242 LIBBPF_API int btf__add_enum64(struct btf *btf, const char *name, __u32 bytes_sz, bool is_signed);
243 LIBBPF_API int btf__add_enum64_value(struct btf *btf, const char *name, __u64 value);
244
245 enum btf_fwd_kind {
246 BTF_FWD_STRUCT = 0,
247 BTF_FWD_UNION = 1,
248 BTF_FWD_ENUM = 2,
249 };
250
251 LIBBPF_API int btf__add_fwd(struct btf *btf, const char *name, enum btf_fwd_kind fwd_kind);
252 LIBBPF_API int btf__add_typedef(struct btf *btf, const char *name, int ref_type_id);
253 LIBBPF_API int btf__add_volatile(struct btf *btf, int ref_type_id);
254 LIBBPF_API int btf__add_const(struct btf *btf, int ref_type_id);
255 LIBBPF_API int btf__add_restrict(struct btf *btf, int ref_type_id);
256 LIBBPF_API int btf__add_type_tag(struct btf *btf, const char *value, int ref_type_id);
257 LIBBPF_API int btf__add_type_attr(struct btf *btf, const char *value, int ref_type_id);
258
259 /* func and func_proto construction APIs */
260 LIBBPF_API int btf__add_func(struct btf *btf, const char *name,
261 enum btf_func_linkage linkage, int proto_type_id);
262 LIBBPF_API int btf__add_func_proto(struct btf *btf, int ret_type_id);
263 LIBBPF_API int btf__add_func_param(struct btf *btf, const char *name, int type_id);
264
265 /* var & datasec construction APIs */
266 LIBBPF_API int btf__add_var(struct btf *btf, const char *name, int linkage, int type_id);
267 LIBBPF_API int btf__add_datasec(struct btf *btf, const char *name, __u32 byte_sz);
268 LIBBPF_API int btf__add_datasec_var_info(struct btf *btf, int var_type_id,
269 __u32 offset, __u32 byte_sz);
270
271 /* tag construction API */
272 LIBBPF_API int btf__add_decl_tag(struct btf *btf, const char *value, int ref_type_id,
273 int component_idx);
274 LIBBPF_API int btf__add_decl_attr(struct btf *btf, const char *value, int ref_type_id,
275 int component_idx);
276
277 struct btf_dedup_opts {
278 size_t sz;
279 /* optional .BTF.ext info to dedup along the main BTF info */
280 struct btf_ext *btf_ext;
281 /* force hash collisions (used for testing) */
282 bool force_collisions;
283 size_t :0;
284 };
285 #define btf_dedup_opts__last_field force_collisions
286
287 LIBBPF_API int btf__dedup(struct btf *btf, const struct btf_dedup_opts *opts);
288
289 /**
290 * @brief **btf__relocate()** will check the split BTF *btf* for references
291 * to base BTF kinds, and verify those references are compatible with
292 * *base_btf*; if they are, *btf* is adjusted such that is re-parented to
293 * *base_btf* and type ids and strings are adjusted to accommodate this.
294 * @param btf split BTF object to relocate
295 * @param base_btf base BTF object
296 * @return 0 on success; negative error code, otherwise
297 *
298 * If successful, 0 is returned and **btf** now has **base_btf** as its
299 * base.
300 *
301 * A negative value is returned on error and the thread-local `errno` variable
302 * is set to the error code as well.
303 */
304 LIBBPF_API int btf__relocate(struct btf *btf, const struct btf *base_btf);
305
306 struct btf_permute_opts {
307 size_t sz;
308 /* optional .BTF.ext info along the main BTF info */
309 struct btf_ext *btf_ext;
310 size_t :0;
311 };
312 #define btf_permute_opts__last_field btf_ext
313
314 /**
315 * @brief **btf__permute()** rearranges BTF types in-place according to a specified ID mapping
316 * @param btf BTF object to permute
317 * @param id_map Array mapping original type IDs to new IDs
318 * @param id_map_cnt Number of elements in @id_map
319 * @param opts Optional parameters, including BTF extension data for reference updates
320 * @return 0 on success, negative error code on failure
321 *
322 * **btf__permute()** reorders BTF types based on the provided @id_map array,
323 * updating all internal type references to maintain consistency. The function
324 * operates in-place, modifying the BTF object directly.
325 *
326 * For **base BTF**:
327 * - @id_map must include all types from ID 0 to `btf__type_cnt(btf) - 1`
328 * - @id_map_cnt must be `btf__type_cnt(btf)`
329 * - Mapping is defined as `id_map[original_id] = new_id`
330 * - `id_map[0]` must be 0 (void type cannot be moved)
331 *
332 * For **split BTF**:
333 * - @id_map must include only split types (types added on top of the base BTF)
334 * - @id_map_cnt must be `btf__type_cnt(btf) - btf__type_cnt(btf__base_btf(btf))`
335 * - Mapping is defined as `id_map[original_id - start_id] = new_id`
336 * - `start_id` equals `btf__type_cnt(btf__base_btf(btf))`
337 *
338 * After permutation, all type references within the BTF data and optional
339 * BTF extension (if provided via @opts) are updated automatically.
340 *
341 * On error, returns a negative error code and sets errno:
342 * - `-EINVAL`: Invalid parameters or invalid ID mapping
343 * - `-ENOMEM`: Memory allocation failure
344 */
345 LIBBPF_API int btf__permute(struct btf *btf, __u32 *id_map, __u32 id_map_cnt,
346 const struct btf_permute_opts *opts);
347
348 struct btf_dump;
349
350 struct btf_dump_opts {
351 size_t sz;
352 };
353 #define btf_dump_opts__last_field sz
354
355 typedef void (*btf_dump_printf_fn_t)(void *ctx, const char *fmt, va_list args);
356
357 LIBBPF_API struct btf_dump *btf_dump__new(const struct btf *btf,
358 btf_dump_printf_fn_t printf_fn,
359 void *ctx,
360 const struct btf_dump_opts *opts);
361
362 LIBBPF_API void btf_dump__free(struct btf_dump *d);
363
364 LIBBPF_API int btf_dump__dump_type(struct btf_dump *d, __u32 id);
365
366 struct btf_dump_emit_type_decl_opts {
367 /* size of this struct, for forward/backward compatibility */
368 size_t sz;
369 /* optional field name for type declaration, e.g.:
370 * - struct my_struct <FNAME>
371 * - void (*<FNAME>)(int)
372 * - char (*<FNAME>)[123]
373 */
374 const char *field_name;
375 /* extra indentation level (in number of tabs) to emit for multi-line
376 * type declarations (e.g., anonymous struct); applies for lines
377 * starting from the second one (first line is assumed to have
378 * necessary indentation already
379 */
380 int indent_level;
381 /* strip all the const/volatile/restrict mods */
382 bool strip_mods;
383 size_t :0;
384 };
385 #define btf_dump_emit_type_decl_opts__last_field strip_mods
386
387 LIBBPF_API int
388 btf_dump__emit_type_decl(struct btf_dump *d, __u32 id,
389 const struct btf_dump_emit_type_decl_opts *opts);
390
391
392 struct btf_dump_type_data_opts {
393 /* size of this struct, for forward/backward compatibility */
394 size_t sz;
395 const char *indent_str;
396 int indent_level;
397 /* below match "show" flags for bpf_show_snprintf() */
398 bool compact; /* no newlines/indentation */
399 bool skip_names; /* skip member/type names */
400 bool emit_zeroes; /* show 0-valued fields */
401 bool emit_strings; /* print char arrays as strings */
402 size_t :0;
403 };
404 #define btf_dump_type_data_opts__last_field emit_strings
405
406 LIBBPF_API int
407 btf_dump__dump_type_data(struct btf_dump *d, __u32 id,
408 const void *data, size_t data_sz,
409 const struct btf_dump_type_data_opts *opts);
410
411 /*
412 * A set of helpers for easier BTF types handling.
413 *
414 * The inline functions below rely on constants from the kernel headers which
415 * may not be available for applications including this header file. To avoid
416 * compilation errors, we define all the constants here that were added after
417 * the initial introduction of the BTF_KIND* constants.
418 */
419 #ifndef BTF_KIND_FUNC
420 #define BTF_KIND_FUNC 12 /* Function */
421 #define BTF_KIND_FUNC_PROTO 13 /* Function Proto */
422 #endif
423 #ifndef BTF_KIND_VAR
424 #define BTF_KIND_VAR 14 /* Variable */
425 #define BTF_KIND_DATASEC 15 /* Section */
426 #endif
427 #ifndef BTF_KIND_FLOAT
428 #define BTF_KIND_FLOAT 16 /* Floating point */
429 #endif
430 /* The kernel header switched to enums, so the following were never #defined */
431 #define BTF_KIND_DECL_TAG 17 /* Decl Tag */
432 #define BTF_KIND_TYPE_TAG 18 /* Type Tag */
433 #define BTF_KIND_ENUM64 19 /* Enum for up-to 64bit values */
434
btf_kind(const struct btf_type * t)435 static inline __u16 btf_kind(const struct btf_type *t)
436 {
437 return BTF_INFO_KIND(t->info);
438 }
439
btf_vlen(const struct btf_type * t)440 static inline __u32 btf_vlen(const struct btf_type *t)
441 {
442 return BTF_INFO_VLEN(t->info);
443 }
444
btf_kflag(const struct btf_type * t)445 static inline bool btf_kflag(const struct btf_type *t)
446 {
447 return BTF_INFO_KFLAG(t->info);
448 }
449
btf_is_void(const struct btf_type * t)450 static inline bool btf_is_void(const struct btf_type *t)
451 {
452 return btf_kind(t) == BTF_KIND_UNKN;
453 }
454
btf_is_int(const struct btf_type * t)455 static inline bool btf_is_int(const struct btf_type *t)
456 {
457 return btf_kind(t) == BTF_KIND_INT;
458 }
459
btf_is_ptr(const struct btf_type * t)460 static inline bool btf_is_ptr(const struct btf_type *t)
461 {
462 return btf_kind(t) == BTF_KIND_PTR;
463 }
464
btf_is_array(const struct btf_type * t)465 static inline bool btf_is_array(const struct btf_type *t)
466 {
467 return btf_kind(t) == BTF_KIND_ARRAY;
468 }
469
btf_is_struct(const struct btf_type * t)470 static inline bool btf_is_struct(const struct btf_type *t)
471 {
472 return btf_kind(t) == BTF_KIND_STRUCT;
473 }
474
btf_is_union(const struct btf_type * t)475 static inline bool btf_is_union(const struct btf_type *t)
476 {
477 return btf_kind(t) == BTF_KIND_UNION;
478 }
479
btf_is_composite(const struct btf_type * t)480 static inline bool btf_is_composite(const struct btf_type *t)
481 {
482 __u16 kind = btf_kind(t);
483
484 return kind == BTF_KIND_STRUCT || kind == BTF_KIND_UNION;
485 }
486
btf_is_enum(const struct btf_type * t)487 static inline bool btf_is_enum(const struct btf_type *t)
488 {
489 return btf_kind(t) == BTF_KIND_ENUM;
490 }
491
btf_is_enum64(const struct btf_type * t)492 static inline bool btf_is_enum64(const struct btf_type *t)
493 {
494 return btf_kind(t) == BTF_KIND_ENUM64;
495 }
496
btf_is_fwd(const struct btf_type * t)497 static inline bool btf_is_fwd(const struct btf_type *t)
498 {
499 return btf_kind(t) == BTF_KIND_FWD;
500 }
501
btf_is_typedef(const struct btf_type * t)502 static inline bool btf_is_typedef(const struct btf_type *t)
503 {
504 return btf_kind(t) == BTF_KIND_TYPEDEF;
505 }
506
btf_is_volatile(const struct btf_type * t)507 static inline bool btf_is_volatile(const struct btf_type *t)
508 {
509 return btf_kind(t) == BTF_KIND_VOLATILE;
510 }
511
btf_is_const(const struct btf_type * t)512 static inline bool btf_is_const(const struct btf_type *t)
513 {
514 return btf_kind(t) == BTF_KIND_CONST;
515 }
516
btf_is_restrict(const struct btf_type * t)517 static inline bool btf_is_restrict(const struct btf_type *t)
518 {
519 return btf_kind(t) == BTF_KIND_RESTRICT;
520 }
521
btf_is_mod(const struct btf_type * t)522 static inline bool btf_is_mod(const struct btf_type *t)
523 {
524 __u16 kind = btf_kind(t);
525
526 return kind == BTF_KIND_VOLATILE ||
527 kind == BTF_KIND_CONST ||
528 kind == BTF_KIND_RESTRICT ||
529 kind == BTF_KIND_TYPE_TAG;
530 }
531
btf_is_func(const struct btf_type * t)532 static inline bool btf_is_func(const struct btf_type *t)
533 {
534 return btf_kind(t) == BTF_KIND_FUNC;
535 }
536
btf_is_func_proto(const struct btf_type * t)537 static inline bool btf_is_func_proto(const struct btf_type *t)
538 {
539 return btf_kind(t) == BTF_KIND_FUNC_PROTO;
540 }
541
btf_is_var(const struct btf_type * t)542 static inline bool btf_is_var(const struct btf_type *t)
543 {
544 return btf_kind(t) == BTF_KIND_VAR;
545 }
546
btf_is_datasec(const struct btf_type * t)547 static inline bool btf_is_datasec(const struct btf_type *t)
548 {
549 return btf_kind(t) == BTF_KIND_DATASEC;
550 }
551
btf_is_float(const struct btf_type * t)552 static inline bool btf_is_float(const struct btf_type *t)
553 {
554 return btf_kind(t) == BTF_KIND_FLOAT;
555 }
556
btf_is_decl_tag(const struct btf_type * t)557 static inline bool btf_is_decl_tag(const struct btf_type *t)
558 {
559 return btf_kind(t) == BTF_KIND_DECL_TAG;
560 }
561
btf_is_type_tag(const struct btf_type * t)562 static inline bool btf_is_type_tag(const struct btf_type *t)
563 {
564 return btf_kind(t) == BTF_KIND_TYPE_TAG;
565 }
566
btf_is_any_enum(const struct btf_type * t)567 static inline bool btf_is_any_enum(const struct btf_type *t)
568 {
569 return btf_is_enum(t) || btf_is_enum64(t);
570 }
571
btf_kind_core_compat(const struct btf_type * t1,const struct btf_type * t2)572 static inline bool btf_kind_core_compat(const struct btf_type *t1,
573 const struct btf_type *t2)
574 {
575 return btf_kind(t1) == btf_kind(t2) ||
576 (btf_is_any_enum(t1) && btf_is_any_enum(t2));
577 }
578
btf_int_encoding(const struct btf_type * t)579 static inline __u8 btf_int_encoding(const struct btf_type *t)
580 {
581 return BTF_INT_ENCODING(*(__u32 *)(t + 1));
582 }
583
btf_int_offset(const struct btf_type * t)584 static inline __u8 btf_int_offset(const struct btf_type *t)
585 {
586 return BTF_INT_OFFSET(*(__u32 *)(t + 1));
587 }
588
btf_int_bits(const struct btf_type * t)589 static inline __u8 btf_int_bits(const struct btf_type *t)
590 {
591 return BTF_INT_BITS(*(__u32 *)(t + 1));
592 }
593
btf_array(const struct btf_type * t)594 static inline struct btf_array *btf_array(const struct btf_type *t)
595 {
596 return (struct btf_array *)(t + 1);
597 }
598
btf_enum(const struct btf_type * t)599 static inline struct btf_enum *btf_enum(const struct btf_type *t)
600 {
601 return (struct btf_enum *)(t + 1);
602 }
603
604 struct btf_enum64;
605
btf_enum64(const struct btf_type * t)606 static inline struct btf_enum64 *btf_enum64(const struct btf_type *t)
607 {
608 return (struct btf_enum64 *)(t + 1);
609 }
610
btf_enum64_value(const struct btf_enum64 * e)611 static inline __u64 btf_enum64_value(const struct btf_enum64 *e)
612 {
613 /* struct btf_enum64 is introduced in Linux 6.0, which is very
614 * bleeding-edge. Here we are avoiding relying on struct btf_enum64
615 * definition coming from kernel UAPI headers to support wider range
616 * of system-wide kernel headers.
617 *
618 * Given this header can be also included from C++ applications, that
619 * further restricts C tricks we can use (like using compatible
620 * anonymous struct). So just treat struct btf_enum64 as
621 * a three-element array of u32 and access second (lo32) and third
622 * (hi32) elements directly.
623 *
624 * For reference, here is a struct btf_enum64 definition:
625 *
626 * const struct btf_enum64 {
627 * __u32 name_off;
628 * __u32 val_lo32;
629 * __u32 val_hi32;
630 * };
631 */
632 const __u32 *e64 = (const __u32 *)e;
633
634 return ((__u64)e64[2] << 32) | e64[1];
635 }
636
btf_members(const struct btf_type * t)637 static inline struct btf_member *btf_members(const struct btf_type *t)
638 {
639 return (struct btf_member *)(t + 1);
640 }
641
642 /* Get bit offset of a member with specified index. */
btf_member_bit_offset(const struct btf_type * t,__u32 member_idx)643 static inline __u32 btf_member_bit_offset(const struct btf_type *t,
644 __u32 member_idx)
645 {
646 const struct btf_member *m = btf_members(t) + member_idx;
647 bool kflag = btf_kflag(t);
648
649 return kflag ? BTF_MEMBER_BIT_OFFSET(m->offset) : m->offset;
650 }
651 /*
652 * Get bitfield size of a member, assuming t is BTF_KIND_STRUCT or
653 * BTF_KIND_UNION. If member is not a bitfield, zero is returned.
654 */
btf_member_bitfield_size(const struct btf_type * t,__u32 member_idx)655 static inline __u32 btf_member_bitfield_size(const struct btf_type *t,
656 __u32 member_idx)
657 {
658 const struct btf_member *m = btf_members(t) + member_idx;
659 bool kflag = btf_kflag(t);
660
661 return kflag ? BTF_MEMBER_BITFIELD_SIZE(m->offset) : 0;
662 }
663
btf_params(const struct btf_type * t)664 static inline struct btf_param *btf_params(const struct btf_type *t)
665 {
666 return (struct btf_param *)(t + 1);
667 }
668
btf_var(const struct btf_type * t)669 static inline struct btf_var *btf_var(const struct btf_type *t)
670 {
671 return (struct btf_var *)(t + 1);
672 }
673
674 static inline struct btf_var_secinfo *
btf_var_secinfos(const struct btf_type * t)675 btf_var_secinfos(const struct btf_type *t)
676 {
677 return (struct btf_var_secinfo *)(t + 1);
678 }
679
680 struct btf_decl_tag;
btf_decl_tag(const struct btf_type * t)681 static inline struct btf_decl_tag *btf_decl_tag(const struct btf_type *t)
682 {
683 return (struct btf_decl_tag *)(t + 1);
684 }
685
686 #ifdef __cplusplus
687 } /* extern "C" */
688 #endif
689
690 #endif /* __LIBBPF_BTF_H */
691