xref: /openbmc/linux/tools/lib/bpf/btf.h (revision 87dbdc23)
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 MAPS_ELF_SEC ".maps"
22 
23 struct btf;
24 struct btf_ext;
25 struct btf_type;
26 
27 struct bpf_object;
28 
29 enum btf_endianness {
30 	BTF_LITTLE_ENDIAN = 0,
31 	BTF_BIG_ENDIAN = 1,
32 };
33 
34 /**
35  * @brief **btf__free()** frees all data of a BTF object
36  * @param btf BTF object to free
37  */
38 LIBBPF_API void btf__free(struct btf *btf);
39 
40 /**
41  * @brief **btf__new()** creates a new instance of a BTF object from the raw
42  * bytes of an ELF's BTF section
43  * @param data raw bytes
44  * @param size number of bytes passed in `data`
45  * @return new BTF object instance which has to be eventually freed with
46  * **btf__free()**
47  *
48  * On error, error-code-encoded-as-pointer is returned, not a NULL. To extract
49  * error code from such a pointer `libbpf_get_error()` should be used. If
50  * `libbpf_set_strict_mode(LIBBPF_STRICT_CLEAN_PTRS)` is enabled, NULL is
51  * returned on error instead. In both cases thread-local `errno` variable is
52  * always set to error code as well.
53  */
54 LIBBPF_API struct btf *btf__new(const void *data, __u32 size);
55 
56 /**
57  * @brief **btf__new_split()** create a new instance of a BTF object from the
58  * provided raw data bytes. It takes another BTF instance, **base_btf**, which
59  * serves as a base BTF, which is extended by types in a newly created BTF
60  * instance
61  * @param data raw bytes
62  * @param size length of raw bytes
63  * @param base_btf the base BTF object
64  * @return new BTF object instance which has to be eventually freed with
65  * **btf__free()**
66  *
67  * If *base_btf* is NULL, `btf__new_split()` is equivalent to `btf__new()` and
68  * creates non-split BTF.
69  *
70  * On error, error-code-encoded-as-pointer is returned, not a NULL. To extract
71  * error code from such a pointer `libbpf_get_error()` should be used. If
72  * `libbpf_set_strict_mode(LIBBPF_STRICT_CLEAN_PTRS)` is enabled, NULL is
73  * returned on error instead. In both cases thread-local `errno` variable is
74  * always set to error code as well.
75  */
76 LIBBPF_API struct btf *btf__new_split(const void *data, __u32 size, struct btf *base_btf);
77 
78 /**
79  * @brief **btf__new_empty()** creates an empty BTF object.  Use
80  * `btf__add_*()` to populate such BTF object.
81  * @return new BTF object instance which has to be eventually freed with
82  * **btf__free()**
83  *
84  * On error, error-code-encoded-as-pointer is returned, not a NULL. To extract
85  * error code from such a pointer `libbpf_get_error()` should be used. If
86  * `libbpf_set_strict_mode(LIBBPF_STRICT_CLEAN_PTRS)` is enabled, NULL is
87  * returned on error instead. In both cases thread-local `errno` variable is
88  * always set to error code as well.
89  */
90 LIBBPF_API struct btf *btf__new_empty(void);
91 
92 /**
93  * @brief **btf__new_empty_split()** creates an unpopulated BTF object from an
94  * ELF BTF section except with a base BTF on top of which split BTF should be
95  * based
96  * @return new BTF object instance which has to be eventually freed with
97  * **btf__free()**
98  *
99  * If *base_btf* is NULL, `btf__new_empty_split()` is equivalent to
100  * `btf__new_empty()` and creates non-split BTF.
101  *
102  * On error, error-code-encoded-as-pointer is returned, not a NULL. To extract
103  * error code from such a pointer `libbpf_get_error()` should be used. If
104  * `libbpf_set_strict_mode(LIBBPF_STRICT_CLEAN_PTRS)` is enabled, NULL is
105  * returned on error instead. In both cases thread-local `errno` variable is
106  * always set to error code as well.
107  */
108 LIBBPF_API struct btf *btf__new_empty_split(struct btf *base_btf);
109 
110 LIBBPF_API struct btf *btf__parse(const char *path, struct btf_ext **btf_ext);
111 LIBBPF_API struct btf *btf__parse_split(const char *path, struct btf *base_btf);
112 LIBBPF_API struct btf *btf__parse_elf(const char *path, struct btf_ext **btf_ext);
113 LIBBPF_API struct btf *btf__parse_elf_split(const char *path, struct btf *base_btf);
114 LIBBPF_API struct btf *btf__parse_raw(const char *path);
115 LIBBPF_API struct btf *btf__parse_raw_split(const char *path, struct btf *base_btf);
116 
117 LIBBPF_API struct btf *btf__load_vmlinux_btf(void);
118 LIBBPF_API struct btf *btf__load_module_btf(const char *module_name, struct btf *vmlinux_btf);
119 
120 LIBBPF_API struct btf *btf__load_from_kernel_by_id(__u32 id);
121 LIBBPF_API struct btf *btf__load_from_kernel_by_id_split(__u32 id, struct btf *base_btf);
122 
123 LIBBPF_API int btf__load_into_kernel(struct btf *btf);
124 LIBBPF_API __s32 btf__find_by_name(const struct btf *btf,
125 				   const char *type_name);
126 LIBBPF_API __s32 btf__find_by_name_kind(const struct btf *btf,
127 					const char *type_name, __u32 kind);
128 LIBBPF_API __u32 btf__type_cnt(const struct btf *btf);
129 LIBBPF_API const struct btf *btf__base_btf(const struct btf *btf);
130 LIBBPF_API const struct btf_type *btf__type_by_id(const struct btf *btf,
131 						  __u32 id);
132 LIBBPF_API size_t btf__pointer_size(const struct btf *btf);
133 LIBBPF_API int btf__set_pointer_size(struct btf *btf, size_t ptr_sz);
134 LIBBPF_API enum btf_endianness btf__endianness(const struct btf *btf);
135 LIBBPF_API int btf__set_endianness(struct btf *btf, enum btf_endianness endian);
136 LIBBPF_API __s64 btf__resolve_size(const struct btf *btf, __u32 type_id);
137 LIBBPF_API int btf__resolve_type(const struct btf *btf, __u32 type_id);
138 LIBBPF_API int btf__align_of(const struct btf *btf, __u32 id);
139 LIBBPF_API int btf__fd(const struct btf *btf);
140 LIBBPF_API void btf__set_fd(struct btf *btf, int fd);
141 LIBBPF_API const void *btf__raw_data(const struct btf *btf, __u32 *size);
142 LIBBPF_API const char *btf__name_by_offset(const struct btf *btf, __u32 offset);
143 LIBBPF_API const char *btf__str_by_offset(const struct btf *btf, __u32 offset);
144 
145 LIBBPF_API struct btf_ext *btf_ext__new(const __u8 *data, __u32 size);
146 LIBBPF_API void btf_ext__free(struct btf_ext *btf_ext);
147 LIBBPF_API const void *btf_ext__raw_data(const struct btf_ext *btf_ext, __u32 *size);
148 
149 LIBBPF_API int btf__find_str(struct btf *btf, const char *s);
150 LIBBPF_API int btf__add_str(struct btf *btf, const char *s);
151 LIBBPF_API int btf__add_type(struct btf *btf, const struct btf *src_btf,
152 			     const struct btf_type *src_type);
153 /**
154  * @brief **btf__add_btf()** appends all the BTF types from *src_btf* into *btf*
155  * @param btf BTF object which all the BTF types and strings are added to
156  * @param src_btf BTF object which all BTF types and referenced strings are copied from
157  * @return BTF type ID of the first appended BTF type, or negative error code
158  *
159  * **btf__add_btf()** can be used to simply and efficiently append the entire
160  * contents of one BTF object to another one. All the BTF type data is copied
161  * over, all referenced type IDs are adjusted by adding a necessary ID offset.
162  * Only strings referenced from BTF types are copied over and deduplicated, so
163  * if there were some unused strings in *src_btf*, those won't be copied over,
164  * which is consistent with the general string deduplication semantics of BTF
165  * writing APIs.
166  *
167  * If any error is encountered during this process, the contents of *btf* is
168  * left intact, which means that **btf__add_btf()** follows the transactional
169  * semantics and the operation as a whole is all-or-nothing.
170  *
171  * *src_btf* has to be non-split BTF, as of now copying types from split BTF
172  * is not supported and will result in -ENOTSUP error code returned.
173  */
174 LIBBPF_API int btf__add_btf(struct btf *btf, const struct btf *src_btf);
175 
176 LIBBPF_API int btf__add_int(struct btf *btf, const char *name, size_t byte_sz, int encoding);
177 LIBBPF_API int btf__add_float(struct btf *btf, const char *name, size_t byte_sz);
178 LIBBPF_API int btf__add_ptr(struct btf *btf, int ref_type_id);
179 LIBBPF_API int btf__add_array(struct btf *btf,
180 			      int index_type_id, int elem_type_id, __u32 nr_elems);
181 /* struct/union construction APIs */
182 LIBBPF_API int btf__add_struct(struct btf *btf, const char *name, __u32 sz);
183 LIBBPF_API int btf__add_union(struct btf *btf, const char *name, __u32 sz);
184 LIBBPF_API int btf__add_field(struct btf *btf, const char *name, int field_type_id,
185 			      __u32 bit_offset, __u32 bit_size);
186 
187 /* enum construction APIs */
188 LIBBPF_API int btf__add_enum(struct btf *btf, const char *name, __u32 bytes_sz);
189 LIBBPF_API int btf__add_enum_value(struct btf *btf, const char *name, __s64 value);
190 LIBBPF_API int btf__add_enum64(struct btf *btf, const char *name, __u32 bytes_sz, bool is_signed);
191 LIBBPF_API int btf__add_enum64_value(struct btf *btf, const char *name, __u64 value);
192 
193 enum btf_fwd_kind {
194 	BTF_FWD_STRUCT = 0,
195 	BTF_FWD_UNION = 1,
196 	BTF_FWD_ENUM = 2,
197 };
198 
199 LIBBPF_API int btf__add_fwd(struct btf *btf, const char *name, enum btf_fwd_kind fwd_kind);
200 LIBBPF_API int btf__add_typedef(struct btf *btf, const char *name, int ref_type_id);
201 LIBBPF_API int btf__add_volatile(struct btf *btf, int ref_type_id);
202 LIBBPF_API int btf__add_const(struct btf *btf, int ref_type_id);
203 LIBBPF_API int btf__add_restrict(struct btf *btf, int ref_type_id);
204 LIBBPF_API int btf__add_type_tag(struct btf *btf, const char *value, int ref_type_id);
205 
206 /* func and func_proto construction APIs */
207 LIBBPF_API int btf__add_func(struct btf *btf, const char *name,
208 			     enum btf_func_linkage linkage, int proto_type_id);
209 LIBBPF_API int btf__add_func_proto(struct btf *btf, int ret_type_id);
210 LIBBPF_API int btf__add_func_param(struct btf *btf, const char *name, int type_id);
211 
212 /* var & datasec construction APIs */
213 LIBBPF_API int btf__add_var(struct btf *btf, const char *name, int linkage, int type_id);
214 LIBBPF_API int btf__add_datasec(struct btf *btf, const char *name, __u32 byte_sz);
215 LIBBPF_API int btf__add_datasec_var_info(struct btf *btf, int var_type_id,
216 					 __u32 offset, __u32 byte_sz);
217 
218 /* tag construction API */
219 LIBBPF_API int btf__add_decl_tag(struct btf *btf, const char *value, int ref_type_id,
220 			    int component_idx);
221 
222 struct btf_dedup_opts {
223 	size_t sz;
224 	/* optional .BTF.ext info to dedup along the main BTF info */
225 	struct btf_ext *btf_ext;
226 	/* force hash collisions (used for testing) */
227 	bool force_collisions;
228 	size_t :0;
229 };
230 #define btf_dedup_opts__last_field force_collisions
231 
232 LIBBPF_API int btf__dedup(struct btf *btf, const struct btf_dedup_opts *opts);
233 
234 struct btf_dump;
235 
236 struct btf_dump_opts {
237 	size_t sz;
238 };
239 #define btf_dump_opts__last_field sz
240 
241 typedef void (*btf_dump_printf_fn_t)(void *ctx, const char *fmt, va_list args);
242 
243 LIBBPF_API struct btf_dump *btf_dump__new(const struct btf *btf,
244 					  btf_dump_printf_fn_t printf_fn,
245 					  void *ctx,
246 					  const struct btf_dump_opts *opts);
247 
248 LIBBPF_API void btf_dump__free(struct btf_dump *d);
249 
250 LIBBPF_API int btf_dump__dump_type(struct btf_dump *d, __u32 id);
251 
252 struct btf_dump_emit_type_decl_opts {
253 	/* size of this struct, for forward/backward compatiblity */
254 	size_t sz;
255 	/* optional field name for type declaration, e.g.:
256 	 * - struct my_struct <FNAME>
257 	 * - void (*<FNAME>)(int)
258 	 * - char (*<FNAME>)[123]
259 	 */
260 	const char *field_name;
261 	/* extra indentation level (in number of tabs) to emit for multi-line
262 	 * type declarations (e.g., anonymous struct); applies for lines
263 	 * starting from the second one (first line is assumed to have
264 	 * necessary indentation already
265 	 */
266 	int indent_level;
267 	/* strip all the const/volatile/restrict mods */
268 	bool strip_mods;
269 	size_t :0;
270 };
271 #define btf_dump_emit_type_decl_opts__last_field strip_mods
272 
273 LIBBPF_API int
274 btf_dump__emit_type_decl(struct btf_dump *d, __u32 id,
275 			 const struct btf_dump_emit_type_decl_opts *opts);
276 
277 
278 struct btf_dump_type_data_opts {
279 	/* size of this struct, for forward/backward compatibility */
280 	size_t sz;
281 	const char *indent_str;
282 	int indent_level;
283 	/* below match "show" flags for bpf_show_snprintf() */
284 	bool compact;		/* no newlines/indentation */
285 	bool skip_names;	/* skip member/type names */
286 	bool emit_zeroes;	/* show 0-valued fields */
287 	size_t :0;
288 };
289 #define btf_dump_type_data_opts__last_field emit_zeroes
290 
291 LIBBPF_API int
292 btf_dump__dump_type_data(struct btf_dump *d, __u32 id,
293 			 const void *data, size_t data_sz,
294 			 const struct btf_dump_type_data_opts *opts);
295 
296 /*
297  * A set of helpers for easier BTF types handling.
298  *
299  * The inline functions below rely on constants from the kernel headers which
300  * may not be available for applications including this header file. To avoid
301  * compilation errors, we define all the constants here that were added after
302  * the initial introduction of the BTF_KIND* constants.
303  */
304 #ifndef BTF_KIND_FUNC
305 #define BTF_KIND_FUNC		12	/* Function	*/
306 #define BTF_KIND_FUNC_PROTO	13	/* Function Proto	*/
307 #endif
308 #ifndef BTF_KIND_VAR
309 #define BTF_KIND_VAR		14	/* Variable	*/
310 #define BTF_KIND_DATASEC	15	/* Section	*/
311 #endif
312 #ifndef BTF_KIND_FLOAT
313 #define BTF_KIND_FLOAT		16	/* Floating point	*/
314 #endif
315 /* The kernel header switched to enums, so the following were never #defined */
316 #define BTF_KIND_DECL_TAG	17	/* Decl Tag */
317 #define BTF_KIND_TYPE_TAG	18	/* Type Tag */
318 #define BTF_KIND_ENUM64		19	/* Enum for up-to 64bit values */
319 
btf_kind(const struct btf_type * t)320 static inline __u16 btf_kind(const struct btf_type *t)
321 {
322 	return BTF_INFO_KIND(t->info);
323 }
324 
btf_vlen(const struct btf_type * t)325 static inline __u16 btf_vlen(const struct btf_type *t)
326 {
327 	return BTF_INFO_VLEN(t->info);
328 }
329 
btf_kflag(const struct btf_type * t)330 static inline bool btf_kflag(const struct btf_type *t)
331 {
332 	return BTF_INFO_KFLAG(t->info);
333 }
334 
btf_is_void(const struct btf_type * t)335 static inline bool btf_is_void(const struct btf_type *t)
336 {
337 	return btf_kind(t) == BTF_KIND_UNKN;
338 }
339 
btf_is_int(const struct btf_type * t)340 static inline bool btf_is_int(const struct btf_type *t)
341 {
342 	return btf_kind(t) == BTF_KIND_INT;
343 }
344 
btf_is_ptr(const struct btf_type * t)345 static inline bool btf_is_ptr(const struct btf_type *t)
346 {
347 	return btf_kind(t) == BTF_KIND_PTR;
348 }
349 
btf_is_array(const struct btf_type * t)350 static inline bool btf_is_array(const struct btf_type *t)
351 {
352 	return btf_kind(t) == BTF_KIND_ARRAY;
353 }
354 
btf_is_struct(const struct btf_type * t)355 static inline bool btf_is_struct(const struct btf_type *t)
356 {
357 	return btf_kind(t) == BTF_KIND_STRUCT;
358 }
359 
btf_is_union(const struct btf_type * t)360 static inline bool btf_is_union(const struct btf_type *t)
361 {
362 	return btf_kind(t) == BTF_KIND_UNION;
363 }
364 
btf_is_composite(const struct btf_type * t)365 static inline bool btf_is_composite(const struct btf_type *t)
366 {
367 	__u16 kind = btf_kind(t);
368 
369 	return kind == BTF_KIND_STRUCT || kind == BTF_KIND_UNION;
370 }
371 
btf_is_enum(const struct btf_type * t)372 static inline bool btf_is_enum(const struct btf_type *t)
373 {
374 	return btf_kind(t) == BTF_KIND_ENUM;
375 }
376 
btf_is_enum64(const struct btf_type * t)377 static inline bool btf_is_enum64(const struct btf_type *t)
378 {
379 	return btf_kind(t) == BTF_KIND_ENUM64;
380 }
381 
btf_is_fwd(const struct btf_type * t)382 static inline bool btf_is_fwd(const struct btf_type *t)
383 {
384 	return btf_kind(t) == BTF_KIND_FWD;
385 }
386 
btf_is_typedef(const struct btf_type * t)387 static inline bool btf_is_typedef(const struct btf_type *t)
388 {
389 	return btf_kind(t) == BTF_KIND_TYPEDEF;
390 }
391 
btf_is_volatile(const struct btf_type * t)392 static inline bool btf_is_volatile(const struct btf_type *t)
393 {
394 	return btf_kind(t) == BTF_KIND_VOLATILE;
395 }
396 
btf_is_const(const struct btf_type * t)397 static inline bool btf_is_const(const struct btf_type *t)
398 {
399 	return btf_kind(t) == BTF_KIND_CONST;
400 }
401 
btf_is_restrict(const struct btf_type * t)402 static inline bool btf_is_restrict(const struct btf_type *t)
403 {
404 	return btf_kind(t) == BTF_KIND_RESTRICT;
405 }
406 
btf_is_mod(const struct btf_type * t)407 static inline bool btf_is_mod(const struct btf_type *t)
408 {
409 	__u16 kind = btf_kind(t);
410 
411 	return kind == BTF_KIND_VOLATILE ||
412 	       kind == BTF_KIND_CONST ||
413 	       kind == BTF_KIND_RESTRICT ||
414 	       kind == BTF_KIND_TYPE_TAG;
415 }
416 
btf_is_func(const struct btf_type * t)417 static inline bool btf_is_func(const struct btf_type *t)
418 {
419 	return btf_kind(t) == BTF_KIND_FUNC;
420 }
421 
btf_is_func_proto(const struct btf_type * t)422 static inline bool btf_is_func_proto(const struct btf_type *t)
423 {
424 	return btf_kind(t) == BTF_KIND_FUNC_PROTO;
425 }
426 
btf_is_var(const struct btf_type * t)427 static inline bool btf_is_var(const struct btf_type *t)
428 {
429 	return btf_kind(t) == BTF_KIND_VAR;
430 }
431 
btf_is_datasec(const struct btf_type * t)432 static inline bool btf_is_datasec(const struct btf_type *t)
433 {
434 	return btf_kind(t) == BTF_KIND_DATASEC;
435 }
436 
btf_is_float(const struct btf_type * t)437 static inline bool btf_is_float(const struct btf_type *t)
438 {
439 	return btf_kind(t) == BTF_KIND_FLOAT;
440 }
441 
btf_is_decl_tag(const struct btf_type * t)442 static inline bool btf_is_decl_tag(const struct btf_type *t)
443 {
444 	return btf_kind(t) == BTF_KIND_DECL_TAG;
445 }
446 
btf_is_type_tag(const struct btf_type * t)447 static inline bool btf_is_type_tag(const struct btf_type *t)
448 {
449 	return btf_kind(t) == BTF_KIND_TYPE_TAG;
450 }
451 
btf_is_any_enum(const struct btf_type * t)452 static inline bool btf_is_any_enum(const struct btf_type *t)
453 {
454 	return btf_is_enum(t) || btf_is_enum64(t);
455 }
456 
btf_kind_core_compat(const struct btf_type * t1,const struct btf_type * t2)457 static inline bool btf_kind_core_compat(const struct btf_type *t1,
458 					const struct btf_type *t2)
459 {
460 	return btf_kind(t1) == btf_kind(t2) ||
461 	       (btf_is_any_enum(t1) && btf_is_any_enum(t2));
462 }
463 
btf_int_encoding(const struct btf_type * t)464 static inline __u8 btf_int_encoding(const struct btf_type *t)
465 {
466 	return BTF_INT_ENCODING(*(__u32 *)(t + 1));
467 }
468 
btf_int_offset(const struct btf_type * t)469 static inline __u8 btf_int_offset(const struct btf_type *t)
470 {
471 	return BTF_INT_OFFSET(*(__u32 *)(t + 1));
472 }
473 
btf_int_bits(const struct btf_type * t)474 static inline __u8 btf_int_bits(const struct btf_type *t)
475 {
476 	return BTF_INT_BITS(*(__u32 *)(t + 1));
477 }
478 
btf_array(const struct btf_type * t)479 static inline struct btf_array *btf_array(const struct btf_type *t)
480 {
481 	return (struct btf_array *)(t + 1);
482 }
483 
btf_enum(const struct btf_type * t)484 static inline struct btf_enum *btf_enum(const struct btf_type *t)
485 {
486 	return (struct btf_enum *)(t + 1);
487 }
488 
489 struct btf_enum64;
490 
btf_enum64(const struct btf_type * t)491 static inline struct btf_enum64 *btf_enum64(const struct btf_type *t)
492 {
493 	return (struct btf_enum64 *)(t + 1);
494 }
495 
btf_enum64_value(const struct btf_enum64 * e)496 static inline __u64 btf_enum64_value(const struct btf_enum64 *e)
497 {
498 	/* struct btf_enum64 is introduced in Linux 6.0, which is very
499 	 * bleeding-edge. Here we are avoiding relying on struct btf_enum64
500 	 * definition coming from kernel UAPI headers to support wider range
501 	 * of system-wide kernel headers.
502 	 *
503 	 * Given this header can be also included from C++ applications, that
504 	 * further restricts C tricks we can use (like using compatible
505 	 * anonymous struct). So just treat struct btf_enum64 as
506 	 * a three-element array of u32 and access second (lo32) and third
507 	 * (hi32) elements directly.
508 	 *
509 	 * For reference, here is a struct btf_enum64 definition:
510 	 *
511 	 * const struct btf_enum64 {
512 	 *	__u32	name_off;
513 	 *	__u32	val_lo32;
514 	 *	__u32	val_hi32;
515 	 * };
516 	 */
517 	const __u32 *e64 = (const __u32 *)e;
518 
519 	return ((__u64)e64[2] << 32) | e64[1];
520 }
521 
btf_members(const struct btf_type * t)522 static inline struct btf_member *btf_members(const struct btf_type *t)
523 {
524 	return (struct btf_member *)(t + 1);
525 }
526 
527 /* Get bit offset of a member with specified index. */
btf_member_bit_offset(const struct btf_type * t,__u32 member_idx)528 static inline __u32 btf_member_bit_offset(const struct btf_type *t,
529 					  __u32 member_idx)
530 {
531 	const struct btf_member *m = btf_members(t) + member_idx;
532 	bool kflag = btf_kflag(t);
533 
534 	return kflag ? BTF_MEMBER_BIT_OFFSET(m->offset) : m->offset;
535 }
536 /*
537  * Get bitfield size of a member, assuming t is BTF_KIND_STRUCT or
538  * BTF_KIND_UNION. If member is not a bitfield, zero is returned.
539  */
btf_member_bitfield_size(const struct btf_type * t,__u32 member_idx)540 static inline __u32 btf_member_bitfield_size(const struct btf_type *t,
541 					     __u32 member_idx)
542 {
543 	const struct btf_member *m = btf_members(t) + member_idx;
544 	bool kflag = btf_kflag(t);
545 
546 	return kflag ? BTF_MEMBER_BITFIELD_SIZE(m->offset) : 0;
547 }
548 
btf_params(const struct btf_type * t)549 static inline struct btf_param *btf_params(const struct btf_type *t)
550 {
551 	return (struct btf_param *)(t + 1);
552 }
553 
btf_var(const struct btf_type * t)554 static inline struct btf_var *btf_var(const struct btf_type *t)
555 {
556 	return (struct btf_var *)(t + 1);
557 }
558 
559 static inline struct btf_var_secinfo *
btf_var_secinfos(const struct btf_type * t)560 btf_var_secinfos(const struct btf_type *t)
561 {
562 	return (struct btf_var_secinfo *)(t + 1);
563 }
564 
565 struct btf_decl_tag;
btf_decl_tag(const struct btf_type * t)566 static inline struct btf_decl_tag *btf_decl_tag(const struct btf_type *t)
567 {
568 	return (struct btf_decl_tag *)(t + 1);
569 }
570 
571 #ifdef __cplusplus
572 } /* extern "C" */
573 #endif
574 
575 #endif /* __LIBBPF_BTF_H */
576