xref: /openbmc/linux/tools/lib/bpf/libbpf.h (revision adb57164)
1 /* SPDX-License-Identifier: (LGPL-2.1 OR BSD-2-Clause) */
2 
3 /*
4  * Common eBPF ELF object loading operations.
5  *
6  * Copyright (C) 2013-2015 Alexei Starovoitov <ast@kernel.org>
7  * Copyright (C) 2015 Wang Nan <wangnan0@huawei.com>
8  * Copyright (C) 2015 Huawei Inc.
9  */
10 #ifndef __LIBBPF_LIBBPF_H
11 #define __LIBBPF_LIBBPF_H
12 
13 #include <stdarg.h>
14 #include <stdio.h>
15 #include <stdint.h>
16 #include <stdbool.h>
17 #include <sys/types.h>  // for size_t
18 #include <linux/bpf.h>
19 
20 #include "libbpf_common.h"
21 
22 #ifdef __cplusplus
23 extern "C" {
24 #endif
25 
26 enum libbpf_errno {
27 	__LIBBPF_ERRNO__START = 4000,
28 
29 	/* Something wrong in libelf */
30 	LIBBPF_ERRNO__LIBELF = __LIBBPF_ERRNO__START,
31 	LIBBPF_ERRNO__FORMAT,	/* BPF object format invalid */
32 	LIBBPF_ERRNO__KVERSION,	/* Incorrect or no 'version' section */
33 	LIBBPF_ERRNO__ENDIAN,	/* Endian mismatch */
34 	LIBBPF_ERRNO__INTERNAL,	/* Internal error in libbpf */
35 	LIBBPF_ERRNO__RELOC,	/* Relocation failed */
36 	LIBBPF_ERRNO__LOAD,	/* Load program failure for unknown reason */
37 	LIBBPF_ERRNO__VERIFY,	/* Kernel verifier blocks program loading */
38 	LIBBPF_ERRNO__PROG2BIG,	/* Program too big */
39 	LIBBPF_ERRNO__KVER,	/* Incorrect kernel version */
40 	LIBBPF_ERRNO__PROGTYPE,	/* Kernel doesn't support this program type */
41 	LIBBPF_ERRNO__WRNGPID,	/* Wrong pid in netlink message */
42 	LIBBPF_ERRNO__INVSEQ,	/* Invalid netlink sequence */
43 	LIBBPF_ERRNO__NLPARSE,	/* netlink parsing error */
44 	__LIBBPF_ERRNO__END,
45 };
46 
47 LIBBPF_API int libbpf_strerror(int err, char *buf, size_t size);
48 
49 enum libbpf_print_level {
50         LIBBPF_WARN,
51         LIBBPF_INFO,
52         LIBBPF_DEBUG,
53 };
54 
55 typedef int (*libbpf_print_fn_t)(enum libbpf_print_level level,
56 				 const char *, va_list ap);
57 
58 LIBBPF_API libbpf_print_fn_t libbpf_set_print(libbpf_print_fn_t fn);
59 
60 /* Hide internal to user */
61 struct bpf_object;
62 
63 struct bpf_object_open_attr {
64 	const char *file;
65 	enum bpf_prog_type prog_type;
66 };
67 
68 struct bpf_object_open_opts {
69 	/* size of this struct, for forward/backward compatiblity */
70 	size_t sz;
71 	/* object name override, if provided:
72 	 * - for object open from file, this will override setting object
73 	 *   name from file path's base name;
74 	 * - for object open from memory buffer, this will specify an object
75 	 *   name and will override default "<addr>-<buf-size>" name;
76 	 */
77 	const char *object_name;
78 	/* parse map definitions non-strictly, allowing extra attributes/data */
79 	bool relaxed_maps;
80 	/* DEPRECATED: handle CO-RE relocations non-strictly, allowing failures.
81 	 * Value is ignored. Relocations always are processed non-strictly.
82 	 * Non-relocatable instructions are replaced with invalid ones to
83 	 * prevent accidental errors.
84 	 * */
85 	bool relaxed_core_relocs;
86 	/* maps that set the 'pinning' attribute in their definition will have
87 	 * their pin_path attribute set to a file in this directory, and be
88 	 * auto-pinned to that path on load; defaults to "/sys/fs/bpf".
89 	 */
90 	const char *pin_root_path;
91 	__u32 attach_prog_fd;
92 	/* Additional kernel config content that augments and overrides
93 	 * system Kconfig for CONFIG_xxx externs.
94 	 */
95 	const char *kconfig;
96 };
97 #define bpf_object_open_opts__last_field kconfig
98 
99 LIBBPF_API struct bpf_object *bpf_object__open(const char *path);
100 LIBBPF_API struct bpf_object *
101 bpf_object__open_file(const char *path, const struct bpf_object_open_opts *opts);
102 LIBBPF_API struct bpf_object *
103 bpf_object__open_mem(const void *obj_buf, size_t obj_buf_sz,
104 		     const struct bpf_object_open_opts *opts);
105 
106 /* deprecated bpf_object__open variants */
107 LIBBPF_API struct bpf_object *
108 bpf_object__open_buffer(const void *obj_buf, size_t obj_buf_sz,
109 			const char *name);
110 LIBBPF_API struct bpf_object *
111 bpf_object__open_xattr(struct bpf_object_open_attr *attr);
112 
113 enum libbpf_pin_type {
114 	LIBBPF_PIN_NONE,
115 	/* PIN_BY_NAME: pin maps by name (in /sys/fs/bpf by default) */
116 	LIBBPF_PIN_BY_NAME,
117 };
118 
119 /* pin_maps and unpin_maps can both be called with a NULL path, in which case
120  * they will use the pin_path attribute of each map (and ignore all maps that
121  * don't have a pin_path set).
122  */
123 LIBBPF_API int bpf_object__pin_maps(struct bpf_object *obj, const char *path);
124 LIBBPF_API int bpf_object__unpin_maps(struct bpf_object *obj,
125 				      const char *path);
126 LIBBPF_API int bpf_object__pin_programs(struct bpf_object *obj,
127 					const char *path);
128 LIBBPF_API int bpf_object__unpin_programs(struct bpf_object *obj,
129 					  const char *path);
130 LIBBPF_API int bpf_object__pin(struct bpf_object *object, const char *path);
131 LIBBPF_API void bpf_object__close(struct bpf_object *object);
132 
133 struct bpf_object_load_attr {
134 	struct bpf_object *obj;
135 	int log_level;
136 	const char *target_btf_path;
137 };
138 
139 /* Load/unload object into/from kernel */
140 LIBBPF_API int bpf_object__load(struct bpf_object *obj);
141 LIBBPF_API int bpf_object__load_xattr(struct bpf_object_load_attr *attr);
142 LIBBPF_API int bpf_object__unload(struct bpf_object *obj);
143 
144 LIBBPF_API const char *bpf_object__name(const struct bpf_object *obj);
145 LIBBPF_API unsigned int bpf_object__kversion(const struct bpf_object *obj);
146 
147 struct btf;
148 LIBBPF_API struct btf *bpf_object__btf(const struct bpf_object *obj);
149 LIBBPF_API int bpf_object__btf_fd(const struct bpf_object *obj);
150 
151 LIBBPF_API struct bpf_program *
152 bpf_object__find_program_by_title(const struct bpf_object *obj,
153 				  const char *title);
154 LIBBPF_API struct bpf_program *
155 bpf_object__find_program_by_name(const struct bpf_object *obj,
156 				 const char *name);
157 
158 LIBBPF_API struct bpf_object *bpf_object__next(struct bpf_object *prev);
159 #define bpf_object__for_each_safe(pos, tmp)			\
160 	for ((pos) = bpf_object__next(NULL),		\
161 		(tmp) = bpf_object__next(pos);		\
162 	     (pos) != NULL;				\
163 	     (pos) = (tmp), (tmp) = bpf_object__next(tmp))
164 
165 typedef void (*bpf_object_clear_priv_t)(struct bpf_object *, void *);
166 LIBBPF_API int bpf_object__set_priv(struct bpf_object *obj, void *priv,
167 				    bpf_object_clear_priv_t clear_priv);
168 LIBBPF_API void *bpf_object__priv(const struct bpf_object *prog);
169 
170 LIBBPF_API int
171 libbpf_prog_type_by_name(const char *name, enum bpf_prog_type *prog_type,
172 			 enum bpf_attach_type *expected_attach_type);
173 LIBBPF_API int libbpf_attach_type_by_name(const char *name,
174 					  enum bpf_attach_type *attach_type);
175 LIBBPF_API int libbpf_find_vmlinux_btf_id(const char *name,
176 					  enum bpf_attach_type attach_type);
177 
178 /* Accessors of bpf_program */
179 struct bpf_program;
180 LIBBPF_API struct bpf_program *bpf_program__next(struct bpf_program *prog,
181 						 const struct bpf_object *obj);
182 
183 #define bpf_object__for_each_program(pos, obj)		\
184 	for ((pos) = bpf_program__next(NULL, (obj));	\
185 	     (pos) != NULL;				\
186 	     (pos) = bpf_program__next((pos), (obj)))
187 
188 LIBBPF_API struct bpf_program *bpf_program__prev(struct bpf_program *prog,
189 						 const struct bpf_object *obj);
190 
191 typedef void (*bpf_program_clear_priv_t)(struct bpf_program *, void *);
192 
193 LIBBPF_API int bpf_program__set_priv(struct bpf_program *prog, void *priv,
194 				     bpf_program_clear_priv_t clear_priv);
195 
196 LIBBPF_API void *bpf_program__priv(const struct bpf_program *prog);
197 LIBBPF_API void bpf_program__set_ifindex(struct bpf_program *prog,
198 					 __u32 ifindex);
199 
200 LIBBPF_API const char *bpf_program__name(const struct bpf_program *prog);
201 LIBBPF_API const char *bpf_program__title(const struct bpf_program *prog,
202 					  bool needs_copy);
203 
204 /* returns program size in bytes */
205 LIBBPF_API size_t bpf_program__size(const struct bpf_program *prog);
206 
207 LIBBPF_API int bpf_program__load(struct bpf_program *prog, char *license,
208 				 __u32 kern_version);
209 LIBBPF_API int bpf_program__fd(const struct bpf_program *prog);
210 LIBBPF_API int bpf_program__pin_instance(struct bpf_program *prog,
211 					 const char *path,
212 					 int instance);
213 LIBBPF_API int bpf_program__unpin_instance(struct bpf_program *prog,
214 					   const char *path,
215 					   int instance);
216 LIBBPF_API int bpf_program__pin(struct bpf_program *prog, const char *path);
217 LIBBPF_API int bpf_program__unpin(struct bpf_program *prog, const char *path);
218 LIBBPF_API void bpf_program__unload(struct bpf_program *prog);
219 
220 struct bpf_link;
221 
222 LIBBPF_API struct bpf_link *bpf_link__open(const char *path);
223 LIBBPF_API int bpf_link__fd(const struct bpf_link *link);
224 LIBBPF_API const char *bpf_link__pin_path(const struct bpf_link *link);
225 LIBBPF_API int bpf_link__pin(struct bpf_link *link, const char *path);
226 LIBBPF_API int bpf_link__unpin(struct bpf_link *link);
227 LIBBPF_API int bpf_link__update_program(struct bpf_link *link,
228 					struct bpf_program *prog);
229 LIBBPF_API void bpf_link__disconnect(struct bpf_link *link);
230 LIBBPF_API int bpf_link__destroy(struct bpf_link *link);
231 
232 LIBBPF_API struct bpf_link *
233 bpf_program__attach(struct bpf_program *prog);
234 LIBBPF_API struct bpf_link *
235 bpf_program__attach_perf_event(struct bpf_program *prog, int pfd);
236 LIBBPF_API struct bpf_link *
237 bpf_program__attach_kprobe(struct bpf_program *prog, bool retprobe,
238 			   const char *func_name);
239 LIBBPF_API struct bpf_link *
240 bpf_program__attach_uprobe(struct bpf_program *prog, bool retprobe,
241 			   pid_t pid, const char *binary_path,
242 			   size_t func_offset);
243 LIBBPF_API struct bpf_link *
244 bpf_program__attach_tracepoint(struct bpf_program *prog,
245 			       const char *tp_category,
246 			       const char *tp_name);
247 LIBBPF_API struct bpf_link *
248 bpf_program__attach_raw_tracepoint(struct bpf_program *prog,
249 				   const char *tp_name);
250 LIBBPF_API struct bpf_link *
251 bpf_program__attach_trace(struct bpf_program *prog);
252 LIBBPF_API struct bpf_link *
253 bpf_program__attach_lsm(struct bpf_program *prog);
254 LIBBPF_API struct bpf_link *
255 bpf_program__attach_cgroup(struct bpf_program *prog, int cgroup_fd);
256 
257 struct bpf_map;
258 
259 LIBBPF_API struct bpf_link *bpf_map__attach_struct_ops(struct bpf_map *map);
260 
261 struct bpf_insn;
262 
263 /*
264  * Libbpf allows callers to adjust BPF programs before being loaded
265  * into kernel. One program in an object file can be transformed into
266  * multiple variants to be attached to different hooks.
267  *
268  * bpf_program_prep_t, bpf_program__set_prep and bpf_program__nth_fd
269  * form an API for this purpose.
270  *
271  * - bpf_program_prep_t:
272  *   Defines a 'preprocessor', which is a caller defined function
273  *   passed to libbpf through bpf_program__set_prep(), and will be
274  *   called before program is loaded. The processor should adjust
275  *   the program one time for each instance according to the instance id
276  *   passed to it.
277  *
278  * - bpf_program__set_prep:
279  *   Attaches a preprocessor to a BPF program. The number of instances
280  *   that should be created is also passed through this function.
281  *
282  * - bpf_program__nth_fd:
283  *   After the program is loaded, get resulting FD of a given instance
284  *   of the BPF program.
285  *
286  * If bpf_program__set_prep() is not used, the program would be loaded
287  * without adjustment during bpf_object__load(). The program has only
288  * one instance. In this case bpf_program__fd(prog) is equal to
289  * bpf_program__nth_fd(prog, 0).
290  */
291 
292 struct bpf_prog_prep_result {
293 	/*
294 	 * If not NULL, load new instruction array.
295 	 * If set to NULL, don't load this instance.
296 	 */
297 	struct bpf_insn *new_insn_ptr;
298 	int new_insn_cnt;
299 
300 	/* If not NULL, result FD is written to it. */
301 	int *pfd;
302 };
303 
304 /*
305  * Parameters of bpf_program_prep_t:
306  *  - prog:	The bpf_program being loaded.
307  *  - n:	Index of instance being generated.
308  *  - insns:	BPF instructions array.
309  *  - insns_cnt:Number of instructions in insns.
310  *  - res:	Output parameter, result of transformation.
311  *
312  * Return value:
313  *  - Zero:	pre-processing success.
314  *  - Non-zero:	pre-processing error, stop loading.
315  */
316 typedef int (*bpf_program_prep_t)(struct bpf_program *prog, int n,
317 				  struct bpf_insn *insns, int insns_cnt,
318 				  struct bpf_prog_prep_result *res);
319 
320 LIBBPF_API int bpf_program__set_prep(struct bpf_program *prog, int nr_instance,
321 				     bpf_program_prep_t prep);
322 
323 LIBBPF_API int bpf_program__nth_fd(const struct bpf_program *prog, int n);
324 
325 /*
326  * Adjust type of BPF program. Default is kprobe.
327  */
328 LIBBPF_API int bpf_program__set_socket_filter(struct bpf_program *prog);
329 LIBBPF_API int bpf_program__set_tracepoint(struct bpf_program *prog);
330 LIBBPF_API int bpf_program__set_raw_tracepoint(struct bpf_program *prog);
331 LIBBPF_API int bpf_program__set_kprobe(struct bpf_program *prog);
332 LIBBPF_API int bpf_program__set_lsm(struct bpf_program *prog);
333 LIBBPF_API int bpf_program__set_sched_cls(struct bpf_program *prog);
334 LIBBPF_API int bpf_program__set_sched_act(struct bpf_program *prog);
335 LIBBPF_API int bpf_program__set_xdp(struct bpf_program *prog);
336 LIBBPF_API int bpf_program__set_perf_event(struct bpf_program *prog);
337 LIBBPF_API int bpf_program__set_tracing(struct bpf_program *prog);
338 LIBBPF_API int bpf_program__set_struct_ops(struct bpf_program *prog);
339 LIBBPF_API int bpf_program__set_extension(struct bpf_program *prog);
340 
341 LIBBPF_API enum bpf_prog_type bpf_program__get_type(struct bpf_program *prog);
342 LIBBPF_API void bpf_program__set_type(struct bpf_program *prog,
343 				      enum bpf_prog_type type);
344 
345 LIBBPF_API enum bpf_attach_type
346 bpf_program__get_expected_attach_type(struct bpf_program *prog);
347 LIBBPF_API void
348 bpf_program__set_expected_attach_type(struct bpf_program *prog,
349 				      enum bpf_attach_type type);
350 
351 LIBBPF_API int
352 bpf_program__set_attach_target(struct bpf_program *prog, int attach_prog_fd,
353 			       const char *attach_func_name);
354 
355 LIBBPF_API bool bpf_program__is_socket_filter(const struct bpf_program *prog);
356 LIBBPF_API bool bpf_program__is_tracepoint(const struct bpf_program *prog);
357 LIBBPF_API bool bpf_program__is_raw_tracepoint(const struct bpf_program *prog);
358 LIBBPF_API bool bpf_program__is_kprobe(const struct bpf_program *prog);
359 LIBBPF_API bool bpf_program__is_lsm(const struct bpf_program *prog);
360 LIBBPF_API bool bpf_program__is_sched_cls(const struct bpf_program *prog);
361 LIBBPF_API bool bpf_program__is_sched_act(const struct bpf_program *prog);
362 LIBBPF_API bool bpf_program__is_xdp(const struct bpf_program *prog);
363 LIBBPF_API bool bpf_program__is_perf_event(const struct bpf_program *prog);
364 LIBBPF_API bool bpf_program__is_tracing(const struct bpf_program *prog);
365 LIBBPF_API bool bpf_program__is_struct_ops(const struct bpf_program *prog);
366 LIBBPF_API bool bpf_program__is_extension(const struct bpf_program *prog);
367 
368 /*
369  * No need for __attribute__((packed)), all members of 'bpf_map_def'
370  * are all aligned.  In addition, using __attribute__((packed))
371  * would trigger a -Wpacked warning message, and lead to an error
372  * if -Werror is set.
373  */
374 struct bpf_map_def {
375 	unsigned int type;
376 	unsigned int key_size;
377 	unsigned int value_size;
378 	unsigned int max_entries;
379 	unsigned int map_flags;
380 };
381 
382 /*
383  * The 'struct bpf_map' in include/linux/bpf.h is internal to the kernel,
384  * so no need to worry about a name clash.
385  */
386 LIBBPF_API struct bpf_map *
387 bpf_object__find_map_by_name(const struct bpf_object *obj, const char *name);
388 
389 LIBBPF_API int
390 bpf_object__find_map_fd_by_name(const struct bpf_object *obj, const char *name);
391 
392 /*
393  * Get bpf_map through the offset of corresponding struct bpf_map_def
394  * in the BPF object file.
395  */
396 LIBBPF_API struct bpf_map *
397 bpf_object__find_map_by_offset(struct bpf_object *obj, size_t offset);
398 
399 LIBBPF_API struct bpf_map *
400 bpf_map__next(const struct bpf_map *map, const struct bpf_object *obj);
401 #define bpf_object__for_each_map(pos, obj)		\
402 	for ((pos) = bpf_map__next(NULL, (obj));	\
403 	     (pos) != NULL;				\
404 	     (pos) = bpf_map__next((pos), (obj)))
405 #define bpf_map__for_each bpf_object__for_each_map
406 
407 LIBBPF_API struct bpf_map *
408 bpf_map__prev(const struct bpf_map *map, const struct bpf_object *obj);
409 
410 LIBBPF_API int bpf_map__fd(const struct bpf_map *map);
411 LIBBPF_API const struct bpf_map_def *bpf_map__def(const struct bpf_map *map);
412 LIBBPF_API const char *bpf_map__name(const struct bpf_map *map);
413 LIBBPF_API __u32 bpf_map__btf_key_type_id(const struct bpf_map *map);
414 LIBBPF_API __u32 bpf_map__btf_value_type_id(const struct bpf_map *map);
415 
416 typedef void (*bpf_map_clear_priv_t)(struct bpf_map *, void *);
417 LIBBPF_API int bpf_map__set_priv(struct bpf_map *map, void *priv,
418 				 bpf_map_clear_priv_t clear_priv);
419 LIBBPF_API void *bpf_map__priv(const struct bpf_map *map);
420 LIBBPF_API int bpf_map__set_initial_value(struct bpf_map *map,
421 					  const void *data, size_t size);
422 LIBBPF_API int bpf_map__reuse_fd(struct bpf_map *map, int fd);
423 LIBBPF_API int bpf_map__resize(struct bpf_map *map, __u32 max_entries);
424 LIBBPF_API bool bpf_map__is_offload_neutral(const struct bpf_map *map);
425 LIBBPF_API bool bpf_map__is_internal(const struct bpf_map *map);
426 LIBBPF_API void bpf_map__set_ifindex(struct bpf_map *map, __u32 ifindex);
427 LIBBPF_API int bpf_map__set_pin_path(struct bpf_map *map, const char *path);
428 LIBBPF_API const char *bpf_map__get_pin_path(const struct bpf_map *map);
429 LIBBPF_API bool bpf_map__is_pinned(const struct bpf_map *map);
430 LIBBPF_API int bpf_map__pin(struct bpf_map *map, const char *path);
431 LIBBPF_API int bpf_map__unpin(struct bpf_map *map, const char *path);
432 
433 LIBBPF_API int bpf_map__set_inner_map_fd(struct bpf_map *map, int fd);
434 
435 LIBBPF_API long libbpf_get_error(const void *ptr);
436 
437 struct bpf_prog_load_attr {
438 	const char *file;
439 	enum bpf_prog_type prog_type;
440 	enum bpf_attach_type expected_attach_type;
441 	int ifindex;
442 	int log_level;
443 	int prog_flags;
444 };
445 
446 LIBBPF_API int bpf_prog_load_xattr(const struct bpf_prog_load_attr *attr,
447 				   struct bpf_object **pobj, int *prog_fd);
448 LIBBPF_API int bpf_prog_load(const char *file, enum bpf_prog_type type,
449 			     struct bpf_object **pobj, int *prog_fd);
450 
451 struct xdp_link_info {
452 	__u32 prog_id;
453 	__u32 drv_prog_id;
454 	__u32 hw_prog_id;
455 	__u32 skb_prog_id;
456 	__u8 attach_mode;
457 };
458 
459 struct bpf_xdp_set_link_opts {
460 	size_t sz;
461 	int old_fd;
462 };
463 #define bpf_xdp_set_link_opts__last_field old_fd
464 
465 LIBBPF_API int bpf_set_link_xdp_fd(int ifindex, int fd, __u32 flags);
466 LIBBPF_API int bpf_set_link_xdp_fd_opts(int ifindex, int fd, __u32 flags,
467 					const struct bpf_xdp_set_link_opts *opts);
468 LIBBPF_API int bpf_get_link_xdp_id(int ifindex, __u32 *prog_id, __u32 flags);
469 LIBBPF_API int bpf_get_link_xdp_info(int ifindex, struct xdp_link_info *info,
470 				     size_t info_size, __u32 flags);
471 
472 struct perf_buffer;
473 
474 typedef void (*perf_buffer_sample_fn)(void *ctx, int cpu,
475 				      void *data, __u32 size);
476 typedef void (*perf_buffer_lost_fn)(void *ctx, int cpu, __u64 cnt);
477 
478 /* common use perf buffer options */
479 struct perf_buffer_opts {
480 	/* if specified, sample_cb is called for each sample */
481 	perf_buffer_sample_fn sample_cb;
482 	/* if specified, lost_cb is called for each batch of lost samples */
483 	perf_buffer_lost_fn lost_cb;
484 	/* ctx is provided to sample_cb and lost_cb */
485 	void *ctx;
486 };
487 
488 LIBBPF_API struct perf_buffer *
489 perf_buffer__new(int map_fd, size_t page_cnt,
490 		 const struct perf_buffer_opts *opts);
491 
492 enum bpf_perf_event_ret {
493 	LIBBPF_PERF_EVENT_DONE	= 0,
494 	LIBBPF_PERF_EVENT_ERROR	= -1,
495 	LIBBPF_PERF_EVENT_CONT	= -2,
496 };
497 
498 struct perf_event_header;
499 
500 typedef enum bpf_perf_event_ret
501 (*perf_buffer_event_fn)(void *ctx, int cpu, struct perf_event_header *event);
502 
503 /* raw perf buffer options, giving most power and control */
504 struct perf_buffer_raw_opts {
505 	/* perf event attrs passed directly into perf_event_open() */
506 	struct perf_event_attr *attr;
507 	/* raw event callback */
508 	perf_buffer_event_fn event_cb;
509 	/* ctx is provided to event_cb */
510 	void *ctx;
511 	/* if cpu_cnt == 0, open all on all possible CPUs (up to the number of
512 	 * max_entries of given PERF_EVENT_ARRAY map)
513 	 */
514 	int cpu_cnt;
515 	/* if cpu_cnt > 0, cpus is an array of CPUs to open ring buffers on */
516 	int *cpus;
517 	/* if cpu_cnt > 0, map_keys specify map keys to set per-CPU FDs for */
518 	int *map_keys;
519 };
520 
521 LIBBPF_API struct perf_buffer *
522 perf_buffer__new_raw(int map_fd, size_t page_cnt,
523 		     const struct perf_buffer_raw_opts *opts);
524 
525 LIBBPF_API void perf_buffer__free(struct perf_buffer *pb);
526 LIBBPF_API int perf_buffer__poll(struct perf_buffer *pb, int timeout_ms);
527 
528 typedef enum bpf_perf_event_ret
529 	(*bpf_perf_event_print_t)(struct perf_event_header *hdr,
530 				  void *private_data);
531 LIBBPF_API enum bpf_perf_event_ret
532 bpf_perf_event_read_simple(void *mmap_mem, size_t mmap_size, size_t page_size,
533 			   void **copy_mem, size_t *copy_size,
534 			   bpf_perf_event_print_t fn, void *private_data);
535 
536 struct bpf_prog_linfo;
537 struct bpf_prog_info;
538 
539 LIBBPF_API void bpf_prog_linfo__free(struct bpf_prog_linfo *prog_linfo);
540 LIBBPF_API struct bpf_prog_linfo *
541 bpf_prog_linfo__new(const struct bpf_prog_info *info);
542 LIBBPF_API const struct bpf_line_info *
543 bpf_prog_linfo__lfind_addr_func(const struct bpf_prog_linfo *prog_linfo,
544 				__u64 addr, __u32 func_idx, __u32 nr_skip);
545 LIBBPF_API const struct bpf_line_info *
546 bpf_prog_linfo__lfind(const struct bpf_prog_linfo *prog_linfo,
547 		      __u32 insn_off, __u32 nr_skip);
548 
549 /*
550  * Probe for supported system features
551  *
552  * Note that running many of these probes in a short amount of time can cause
553  * the kernel to reach the maximal size of lockable memory allowed for the
554  * user, causing subsequent probes to fail. In this case, the caller may want
555  * to adjust that limit with setrlimit().
556  */
557 LIBBPF_API bool bpf_probe_prog_type(enum bpf_prog_type prog_type,
558 				    __u32 ifindex);
559 LIBBPF_API bool bpf_probe_map_type(enum bpf_map_type map_type, __u32 ifindex);
560 LIBBPF_API bool bpf_probe_helper(enum bpf_func_id id,
561 				 enum bpf_prog_type prog_type, __u32 ifindex);
562 LIBBPF_API bool bpf_probe_large_insn_limit(__u32 ifindex);
563 
564 /*
565  * Get bpf_prog_info in continuous memory
566  *
567  * struct bpf_prog_info has multiple arrays. The user has option to choose
568  * arrays to fetch from kernel. The following APIs provide an uniform way to
569  * fetch these data. All arrays in bpf_prog_info are stored in a single
570  * continuous memory region. This makes it easy to store the info in a
571  * file.
572  *
573  * Before writing bpf_prog_info_linear to files, it is necessary to
574  * translate pointers in bpf_prog_info to offsets. Helper functions
575  * bpf_program__bpil_addr_to_offs() and bpf_program__bpil_offs_to_addr()
576  * are introduced to switch between pointers and offsets.
577  *
578  * Examples:
579  *   # To fetch map_ids and prog_tags:
580  *   __u64 arrays = (1UL << BPF_PROG_INFO_MAP_IDS) |
581  *           (1UL << BPF_PROG_INFO_PROG_TAGS);
582  *   struct bpf_prog_info_linear *info_linear =
583  *           bpf_program__get_prog_info_linear(fd, arrays);
584  *
585  *   # To save data in file
586  *   bpf_program__bpil_addr_to_offs(info_linear);
587  *   write(f, info_linear, sizeof(*info_linear) + info_linear->data_len);
588  *
589  *   # To read data from file
590  *   read(f, info_linear, <proper_size>);
591  *   bpf_program__bpil_offs_to_addr(info_linear);
592  */
593 enum bpf_prog_info_array {
594 	BPF_PROG_INFO_FIRST_ARRAY = 0,
595 	BPF_PROG_INFO_JITED_INSNS = 0,
596 	BPF_PROG_INFO_XLATED_INSNS,
597 	BPF_PROG_INFO_MAP_IDS,
598 	BPF_PROG_INFO_JITED_KSYMS,
599 	BPF_PROG_INFO_JITED_FUNC_LENS,
600 	BPF_PROG_INFO_FUNC_INFO,
601 	BPF_PROG_INFO_LINE_INFO,
602 	BPF_PROG_INFO_JITED_LINE_INFO,
603 	BPF_PROG_INFO_PROG_TAGS,
604 	BPF_PROG_INFO_LAST_ARRAY,
605 };
606 
607 struct bpf_prog_info_linear {
608 	/* size of struct bpf_prog_info, when the tool is compiled */
609 	__u32			info_len;
610 	/* total bytes allocated for data, round up to 8 bytes */
611 	__u32			data_len;
612 	/* which arrays are included in data */
613 	__u64			arrays;
614 	struct bpf_prog_info	info;
615 	__u8			data[];
616 };
617 
618 LIBBPF_API struct bpf_prog_info_linear *
619 bpf_program__get_prog_info_linear(int fd, __u64 arrays);
620 
621 LIBBPF_API void
622 bpf_program__bpil_addr_to_offs(struct bpf_prog_info_linear *info_linear);
623 
624 LIBBPF_API void
625 bpf_program__bpil_offs_to_addr(struct bpf_prog_info_linear *info_linear);
626 
627 /*
628  * A helper function to get the number of possible CPUs before looking up
629  * per-CPU maps. Negative errno is returned on failure.
630  *
631  * Example usage:
632  *
633  *     int ncpus = libbpf_num_possible_cpus();
634  *     if (ncpus < 0) {
635  *          // error handling
636  *     }
637  *     long values[ncpus];
638  *     bpf_map_lookup_elem(per_cpu_map_fd, key, values);
639  *
640  */
641 LIBBPF_API int libbpf_num_possible_cpus(void);
642 
643 struct bpf_map_skeleton {
644 	const char *name;
645 	struct bpf_map **map;
646 	void **mmaped;
647 };
648 
649 struct bpf_prog_skeleton {
650 	const char *name;
651 	struct bpf_program **prog;
652 	struct bpf_link **link;
653 };
654 
655 struct bpf_object_skeleton {
656 	size_t sz; /* size of this struct, for forward/backward compatibility */
657 
658 	const char *name;
659 	void *data;
660 	size_t data_sz;
661 
662 	struct bpf_object **obj;
663 
664 	int map_cnt;
665 	int map_skel_sz; /* sizeof(struct bpf_skeleton_map) */
666 	struct bpf_map_skeleton *maps;
667 
668 	int prog_cnt;
669 	int prog_skel_sz; /* sizeof(struct bpf_skeleton_prog) */
670 	struct bpf_prog_skeleton *progs;
671 };
672 
673 LIBBPF_API int
674 bpf_object__open_skeleton(struct bpf_object_skeleton *s,
675 			  const struct bpf_object_open_opts *opts);
676 LIBBPF_API int bpf_object__load_skeleton(struct bpf_object_skeleton *s);
677 LIBBPF_API int bpf_object__attach_skeleton(struct bpf_object_skeleton *s);
678 LIBBPF_API void bpf_object__detach_skeleton(struct bpf_object_skeleton *s);
679 LIBBPF_API void bpf_object__destroy_skeleton(struct bpf_object_skeleton *s);
680 
681 enum libbpf_tristate {
682 	TRI_NO = 0,
683 	TRI_YES = 1,
684 	TRI_MODULE = 2,
685 };
686 
687 #ifdef __cplusplus
688 } /* extern "C" */
689 #endif
690 
691 #endif /* __LIBBPF_LIBBPF_H */
692