xref: /openbmc/linux/tools/lib/bpf/libbpf.h (revision 002dff36)
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 LIBBPF_API struct bpf_link *
257 bpf_program__attach_netns(struct bpf_program *prog, int netns_fd);
258 
259 struct bpf_map;
260 
261 LIBBPF_API struct bpf_link *bpf_map__attach_struct_ops(struct bpf_map *map);
262 
263 struct bpf_iter_attach_opts {
264 	size_t sz; /* size of this struct for forward/backward compatibility */
265 };
266 #define bpf_iter_attach_opts__last_field sz
267 
268 LIBBPF_API struct bpf_link *
269 bpf_program__attach_iter(struct bpf_program *prog,
270 			 const struct bpf_iter_attach_opts *opts);
271 
272 struct bpf_insn;
273 
274 /*
275  * Libbpf allows callers to adjust BPF programs before being loaded
276  * into kernel. One program in an object file can be transformed into
277  * multiple variants to be attached to different hooks.
278  *
279  * bpf_program_prep_t, bpf_program__set_prep and bpf_program__nth_fd
280  * form an API for this purpose.
281  *
282  * - bpf_program_prep_t:
283  *   Defines a 'preprocessor', which is a caller defined function
284  *   passed to libbpf through bpf_program__set_prep(), and will be
285  *   called before program is loaded. The processor should adjust
286  *   the program one time for each instance according to the instance id
287  *   passed to it.
288  *
289  * - bpf_program__set_prep:
290  *   Attaches a preprocessor to a BPF program. The number of instances
291  *   that should be created is also passed through this function.
292  *
293  * - bpf_program__nth_fd:
294  *   After the program is loaded, get resulting FD of a given instance
295  *   of the BPF program.
296  *
297  * If bpf_program__set_prep() is not used, the program would be loaded
298  * without adjustment during bpf_object__load(). The program has only
299  * one instance. In this case bpf_program__fd(prog) is equal to
300  * bpf_program__nth_fd(prog, 0).
301  */
302 
303 struct bpf_prog_prep_result {
304 	/*
305 	 * If not NULL, load new instruction array.
306 	 * If set to NULL, don't load this instance.
307 	 */
308 	struct bpf_insn *new_insn_ptr;
309 	int new_insn_cnt;
310 
311 	/* If not NULL, result FD is written to it. */
312 	int *pfd;
313 };
314 
315 /*
316  * Parameters of bpf_program_prep_t:
317  *  - prog:	The bpf_program being loaded.
318  *  - n:	Index of instance being generated.
319  *  - insns:	BPF instructions array.
320  *  - insns_cnt:Number of instructions in insns.
321  *  - res:	Output parameter, result of transformation.
322  *
323  * Return value:
324  *  - Zero:	pre-processing success.
325  *  - Non-zero:	pre-processing error, stop loading.
326  */
327 typedef int (*bpf_program_prep_t)(struct bpf_program *prog, int n,
328 				  struct bpf_insn *insns, int insns_cnt,
329 				  struct bpf_prog_prep_result *res);
330 
331 LIBBPF_API int bpf_program__set_prep(struct bpf_program *prog, int nr_instance,
332 				     bpf_program_prep_t prep);
333 
334 LIBBPF_API int bpf_program__nth_fd(const struct bpf_program *prog, int n);
335 
336 /*
337  * Adjust type of BPF program. Default is kprobe.
338  */
339 LIBBPF_API int bpf_program__set_socket_filter(struct bpf_program *prog);
340 LIBBPF_API int bpf_program__set_tracepoint(struct bpf_program *prog);
341 LIBBPF_API int bpf_program__set_raw_tracepoint(struct bpf_program *prog);
342 LIBBPF_API int bpf_program__set_kprobe(struct bpf_program *prog);
343 LIBBPF_API int bpf_program__set_lsm(struct bpf_program *prog);
344 LIBBPF_API int bpf_program__set_sched_cls(struct bpf_program *prog);
345 LIBBPF_API int bpf_program__set_sched_act(struct bpf_program *prog);
346 LIBBPF_API int bpf_program__set_xdp(struct bpf_program *prog);
347 LIBBPF_API int bpf_program__set_perf_event(struct bpf_program *prog);
348 LIBBPF_API int bpf_program__set_tracing(struct bpf_program *prog);
349 LIBBPF_API int bpf_program__set_struct_ops(struct bpf_program *prog);
350 LIBBPF_API int bpf_program__set_extension(struct bpf_program *prog);
351 
352 LIBBPF_API enum bpf_prog_type bpf_program__get_type(struct bpf_program *prog);
353 LIBBPF_API void bpf_program__set_type(struct bpf_program *prog,
354 				      enum bpf_prog_type type);
355 
356 LIBBPF_API enum bpf_attach_type
357 bpf_program__get_expected_attach_type(struct bpf_program *prog);
358 LIBBPF_API void
359 bpf_program__set_expected_attach_type(struct bpf_program *prog,
360 				      enum bpf_attach_type type);
361 
362 LIBBPF_API int
363 bpf_program__set_attach_target(struct bpf_program *prog, int attach_prog_fd,
364 			       const char *attach_func_name);
365 
366 LIBBPF_API bool bpf_program__is_socket_filter(const struct bpf_program *prog);
367 LIBBPF_API bool bpf_program__is_tracepoint(const struct bpf_program *prog);
368 LIBBPF_API bool bpf_program__is_raw_tracepoint(const struct bpf_program *prog);
369 LIBBPF_API bool bpf_program__is_kprobe(const struct bpf_program *prog);
370 LIBBPF_API bool bpf_program__is_lsm(const struct bpf_program *prog);
371 LIBBPF_API bool bpf_program__is_sched_cls(const struct bpf_program *prog);
372 LIBBPF_API bool bpf_program__is_sched_act(const struct bpf_program *prog);
373 LIBBPF_API bool bpf_program__is_xdp(const struct bpf_program *prog);
374 LIBBPF_API bool bpf_program__is_perf_event(const struct bpf_program *prog);
375 LIBBPF_API bool bpf_program__is_tracing(const struct bpf_program *prog);
376 LIBBPF_API bool bpf_program__is_struct_ops(const struct bpf_program *prog);
377 LIBBPF_API bool bpf_program__is_extension(const struct bpf_program *prog);
378 
379 /*
380  * No need for __attribute__((packed)), all members of 'bpf_map_def'
381  * are all aligned.  In addition, using __attribute__((packed))
382  * would trigger a -Wpacked warning message, and lead to an error
383  * if -Werror is set.
384  */
385 struct bpf_map_def {
386 	unsigned int type;
387 	unsigned int key_size;
388 	unsigned int value_size;
389 	unsigned int max_entries;
390 	unsigned int map_flags;
391 };
392 
393 /*
394  * The 'struct bpf_map' in include/linux/bpf.h is internal to the kernel,
395  * so no need to worry about a name clash.
396  */
397 LIBBPF_API struct bpf_map *
398 bpf_object__find_map_by_name(const struct bpf_object *obj, const char *name);
399 
400 LIBBPF_API int
401 bpf_object__find_map_fd_by_name(const struct bpf_object *obj, const char *name);
402 
403 /*
404  * Get bpf_map through the offset of corresponding struct bpf_map_def
405  * in the BPF object file.
406  */
407 LIBBPF_API struct bpf_map *
408 bpf_object__find_map_by_offset(struct bpf_object *obj, size_t offset);
409 
410 LIBBPF_API struct bpf_map *
411 bpf_map__next(const struct bpf_map *map, const struct bpf_object *obj);
412 #define bpf_object__for_each_map(pos, obj)		\
413 	for ((pos) = bpf_map__next(NULL, (obj));	\
414 	     (pos) != NULL;				\
415 	     (pos) = bpf_map__next((pos), (obj)))
416 #define bpf_map__for_each bpf_object__for_each_map
417 
418 LIBBPF_API struct bpf_map *
419 bpf_map__prev(const struct bpf_map *map, const struct bpf_object *obj);
420 
421 LIBBPF_API int bpf_map__fd(const struct bpf_map *map);
422 LIBBPF_API const struct bpf_map_def *bpf_map__def(const struct bpf_map *map);
423 LIBBPF_API const char *bpf_map__name(const struct bpf_map *map);
424 LIBBPF_API __u32 bpf_map__btf_key_type_id(const struct bpf_map *map);
425 LIBBPF_API __u32 bpf_map__btf_value_type_id(const struct bpf_map *map);
426 
427 typedef void (*bpf_map_clear_priv_t)(struct bpf_map *, void *);
428 LIBBPF_API int bpf_map__set_priv(struct bpf_map *map, void *priv,
429 				 bpf_map_clear_priv_t clear_priv);
430 LIBBPF_API void *bpf_map__priv(const struct bpf_map *map);
431 LIBBPF_API int bpf_map__set_initial_value(struct bpf_map *map,
432 					  const void *data, size_t size);
433 LIBBPF_API int bpf_map__reuse_fd(struct bpf_map *map, int fd);
434 LIBBPF_API int bpf_map__resize(struct bpf_map *map, __u32 max_entries);
435 LIBBPF_API bool bpf_map__is_offload_neutral(const struct bpf_map *map);
436 LIBBPF_API bool bpf_map__is_internal(const struct bpf_map *map);
437 LIBBPF_API void bpf_map__set_ifindex(struct bpf_map *map, __u32 ifindex);
438 LIBBPF_API int bpf_map__set_pin_path(struct bpf_map *map, const char *path);
439 LIBBPF_API const char *bpf_map__get_pin_path(const struct bpf_map *map);
440 LIBBPF_API bool bpf_map__is_pinned(const struct bpf_map *map);
441 LIBBPF_API int bpf_map__pin(struct bpf_map *map, const char *path);
442 LIBBPF_API int bpf_map__unpin(struct bpf_map *map, const char *path);
443 
444 LIBBPF_API int bpf_map__set_inner_map_fd(struct bpf_map *map, int fd);
445 
446 LIBBPF_API long libbpf_get_error(const void *ptr);
447 
448 struct bpf_prog_load_attr {
449 	const char *file;
450 	enum bpf_prog_type prog_type;
451 	enum bpf_attach_type expected_attach_type;
452 	int ifindex;
453 	int log_level;
454 	int prog_flags;
455 };
456 
457 LIBBPF_API int bpf_prog_load_xattr(const struct bpf_prog_load_attr *attr,
458 				   struct bpf_object **pobj, int *prog_fd);
459 LIBBPF_API int bpf_prog_load(const char *file, enum bpf_prog_type type,
460 			     struct bpf_object **pobj, int *prog_fd);
461 
462 struct xdp_link_info {
463 	__u32 prog_id;
464 	__u32 drv_prog_id;
465 	__u32 hw_prog_id;
466 	__u32 skb_prog_id;
467 	__u8 attach_mode;
468 };
469 
470 struct bpf_xdp_set_link_opts {
471 	size_t sz;
472 	int old_fd;
473 };
474 #define bpf_xdp_set_link_opts__last_field old_fd
475 
476 LIBBPF_API int bpf_set_link_xdp_fd(int ifindex, int fd, __u32 flags);
477 LIBBPF_API int bpf_set_link_xdp_fd_opts(int ifindex, int fd, __u32 flags,
478 					const struct bpf_xdp_set_link_opts *opts);
479 LIBBPF_API int bpf_get_link_xdp_id(int ifindex, __u32 *prog_id, __u32 flags);
480 LIBBPF_API int bpf_get_link_xdp_info(int ifindex, struct xdp_link_info *info,
481 				     size_t info_size, __u32 flags);
482 
483 /* Ring buffer APIs */
484 struct ring_buffer;
485 
486 typedef int (*ring_buffer_sample_fn)(void *ctx, void *data, size_t size);
487 
488 struct ring_buffer_opts {
489 	size_t sz; /* size of this struct, for forward/backward compatiblity */
490 };
491 
492 #define ring_buffer_opts__last_field sz
493 
494 LIBBPF_API struct ring_buffer *
495 ring_buffer__new(int map_fd, ring_buffer_sample_fn sample_cb, void *ctx,
496 		 const struct ring_buffer_opts *opts);
497 LIBBPF_API void ring_buffer__free(struct ring_buffer *rb);
498 LIBBPF_API int ring_buffer__add(struct ring_buffer *rb, int map_fd,
499 				ring_buffer_sample_fn sample_cb, void *ctx);
500 LIBBPF_API int ring_buffer__poll(struct ring_buffer *rb, int timeout_ms);
501 LIBBPF_API int ring_buffer__consume(struct ring_buffer *rb);
502 
503 /* Perf buffer APIs */
504 struct perf_buffer;
505 
506 typedef void (*perf_buffer_sample_fn)(void *ctx, int cpu,
507 				      void *data, __u32 size);
508 typedef void (*perf_buffer_lost_fn)(void *ctx, int cpu, __u64 cnt);
509 
510 /* common use perf buffer options */
511 struct perf_buffer_opts {
512 	/* if specified, sample_cb is called for each sample */
513 	perf_buffer_sample_fn sample_cb;
514 	/* if specified, lost_cb is called for each batch of lost samples */
515 	perf_buffer_lost_fn lost_cb;
516 	/* ctx is provided to sample_cb and lost_cb */
517 	void *ctx;
518 };
519 
520 LIBBPF_API struct perf_buffer *
521 perf_buffer__new(int map_fd, size_t page_cnt,
522 		 const struct perf_buffer_opts *opts);
523 
524 enum bpf_perf_event_ret {
525 	LIBBPF_PERF_EVENT_DONE	= 0,
526 	LIBBPF_PERF_EVENT_ERROR	= -1,
527 	LIBBPF_PERF_EVENT_CONT	= -2,
528 };
529 
530 struct perf_event_header;
531 
532 typedef enum bpf_perf_event_ret
533 (*perf_buffer_event_fn)(void *ctx, int cpu, struct perf_event_header *event);
534 
535 /* raw perf buffer options, giving most power and control */
536 struct perf_buffer_raw_opts {
537 	/* perf event attrs passed directly into perf_event_open() */
538 	struct perf_event_attr *attr;
539 	/* raw event callback */
540 	perf_buffer_event_fn event_cb;
541 	/* ctx is provided to event_cb */
542 	void *ctx;
543 	/* if cpu_cnt == 0, open all on all possible CPUs (up to the number of
544 	 * max_entries of given PERF_EVENT_ARRAY map)
545 	 */
546 	int cpu_cnt;
547 	/* if cpu_cnt > 0, cpus is an array of CPUs to open ring buffers on */
548 	int *cpus;
549 	/* if cpu_cnt > 0, map_keys specify map keys to set per-CPU FDs for */
550 	int *map_keys;
551 };
552 
553 LIBBPF_API struct perf_buffer *
554 perf_buffer__new_raw(int map_fd, size_t page_cnt,
555 		     const struct perf_buffer_raw_opts *opts);
556 
557 LIBBPF_API void perf_buffer__free(struct perf_buffer *pb);
558 LIBBPF_API int perf_buffer__poll(struct perf_buffer *pb, int timeout_ms);
559 LIBBPF_API int perf_buffer__consume(struct perf_buffer *pb);
560 
561 typedef enum bpf_perf_event_ret
562 	(*bpf_perf_event_print_t)(struct perf_event_header *hdr,
563 				  void *private_data);
564 LIBBPF_API enum bpf_perf_event_ret
565 bpf_perf_event_read_simple(void *mmap_mem, size_t mmap_size, size_t page_size,
566 			   void **copy_mem, size_t *copy_size,
567 			   bpf_perf_event_print_t fn, void *private_data);
568 
569 struct bpf_prog_linfo;
570 struct bpf_prog_info;
571 
572 LIBBPF_API void bpf_prog_linfo__free(struct bpf_prog_linfo *prog_linfo);
573 LIBBPF_API struct bpf_prog_linfo *
574 bpf_prog_linfo__new(const struct bpf_prog_info *info);
575 LIBBPF_API const struct bpf_line_info *
576 bpf_prog_linfo__lfind_addr_func(const struct bpf_prog_linfo *prog_linfo,
577 				__u64 addr, __u32 func_idx, __u32 nr_skip);
578 LIBBPF_API const struct bpf_line_info *
579 bpf_prog_linfo__lfind(const struct bpf_prog_linfo *prog_linfo,
580 		      __u32 insn_off, __u32 nr_skip);
581 
582 /*
583  * Probe for supported system features
584  *
585  * Note that running many of these probes in a short amount of time can cause
586  * the kernel to reach the maximal size of lockable memory allowed for the
587  * user, causing subsequent probes to fail. In this case, the caller may want
588  * to adjust that limit with setrlimit().
589  */
590 LIBBPF_API bool bpf_probe_prog_type(enum bpf_prog_type prog_type,
591 				    __u32 ifindex);
592 LIBBPF_API bool bpf_probe_map_type(enum bpf_map_type map_type, __u32 ifindex);
593 LIBBPF_API bool bpf_probe_helper(enum bpf_func_id id,
594 				 enum bpf_prog_type prog_type, __u32 ifindex);
595 LIBBPF_API bool bpf_probe_large_insn_limit(__u32 ifindex);
596 
597 /*
598  * Get bpf_prog_info in continuous memory
599  *
600  * struct bpf_prog_info has multiple arrays. The user has option to choose
601  * arrays to fetch from kernel. The following APIs provide an uniform way to
602  * fetch these data. All arrays in bpf_prog_info are stored in a single
603  * continuous memory region. This makes it easy to store the info in a
604  * file.
605  *
606  * Before writing bpf_prog_info_linear to files, it is necessary to
607  * translate pointers in bpf_prog_info to offsets. Helper functions
608  * bpf_program__bpil_addr_to_offs() and bpf_program__bpil_offs_to_addr()
609  * are introduced to switch between pointers and offsets.
610  *
611  * Examples:
612  *   # To fetch map_ids and prog_tags:
613  *   __u64 arrays = (1UL << BPF_PROG_INFO_MAP_IDS) |
614  *           (1UL << BPF_PROG_INFO_PROG_TAGS);
615  *   struct bpf_prog_info_linear *info_linear =
616  *           bpf_program__get_prog_info_linear(fd, arrays);
617  *
618  *   # To save data in file
619  *   bpf_program__bpil_addr_to_offs(info_linear);
620  *   write(f, info_linear, sizeof(*info_linear) + info_linear->data_len);
621  *
622  *   # To read data from file
623  *   read(f, info_linear, <proper_size>);
624  *   bpf_program__bpil_offs_to_addr(info_linear);
625  */
626 enum bpf_prog_info_array {
627 	BPF_PROG_INFO_FIRST_ARRAY = 0,
628 	BPF_PROG_INFO_JITED_INSNS = 0,
629 	BPF_PROG_INFO_XLATED_INSNS,
630 	BPF_PROG_INFO_MAP_IDS,
631 	BPF_PROG_INFO_JITED_KSYMS,
632 	BPF_PROG_INFO_JITED_FUNC_LENS,
633 	BPF_PROG_INFO_FUNC_INFO,
634 	BPF_PROG_INFO_LINE_INFO,
635 	BPF_PROG_INFO_JITED_LINE_INFO,
636 	BPF_PROG_INFO_PROG_TAGS,
637 	BPF_PROG_INFO_LAST_ARRAY,
638 };
639 
640 struct bpf_prog_info_linear {
641 	/* size of struct bpf_prog_info, when the tool is compiled */
642 	__u32			info_len;
643 	/* total bytes allocated for data, round up to 8 bytes */
644 	__u32			data_len;
645 	/* which arrays are included in data */
646 	__u64			arrays;
647 	struct bpf_prog_info	info;
648 	__u8			data[];
649 };
650 
651 LIBBPF_API struct bpf_prog_info_linear *
652 bpf_program__get_prog_info_linear(int fd, __u64 arrays);
653 
654 LIBBPF_API void
655 bpf_program__bpil_addr_to_offs(struct bpf_prog_info_linear *info_linear);
656 
657 LIBBPF_API void
658 bpf_program__bpil_offs_to_addr(struct bpf_prog_info_linear *info_linear);
659 
660 /*
661  * A helper function to get the number of possible CPUs before looking up
662  * per-CPU maps. Negative errno is returned on failure.
663  *
664  * Example usage:
665  *
666  *     int ncpus = libbpf_num_possible_cpus();
667  *     if (ncpus < 0) {
668  *          // error handling
669  *     }
670  *     long values[ncpus];
671  *     bpf_map_lookup_elem(per_cpu_map_fd, key, values);
672  *
673  */
674 LIBBPF_API int libbpf_num_possible_cpus(void);
675 
676 struct bpf_map_skeleton {
677 	const char *name;
678 	struct bpf_map **map;
679 	void **mmaped;
680 };
681 
682 struct bpf_prog_skeleton {
683 	const char *name;
684 	struct bpf_program **prog;
685 	struct bpf_link **link;
686 };
687 
688 struct bpf_object_skeleton {
689 	size_t sz; /* size of this struct, for forward/backward compatibility */
690 
691 	const char *name;
692 	void *data;
693 	size_t data_sz;
694 
695 	struct bpf_object **obj;
696 
697 	int map_cnt;
698 	int map_skel_sz; /* sizeof(struct bpf_skeleton_map) */
699 	struct bpf_map_skeleton *maps;
700 
701 	int prog_cnt;
702 	int prog_skel_sz; /* sizeof(struct bpf_skeleton_prog) */
703 	struct bpf_prog_skeleton *progs;
704 };
705 
706 LIBBPF_API int
707 bpf_object__open_skeleton(struct bpf_object_skeleton *s,
708 			  const struct bpf_object_open_opts *opts);
709 LIBBPF_API int bpf_object__load_skeleton(struct bpf_object_skeleton *s);
710 LIBBPF_API int bpf_object__attach_skeleton(struct bpf_object_skeleton *s);
711 LIBBPF_API void bpf_object__detach_skeleton(struct bpf_object_skeleton *s);
712 LIBBPF_API void bpf_object__destroy_skeleton(struct bpf_object_skeleton *s);
713 
714 enum libbpf_tristate {
715 	TRI_NO = 0,
716 	TRI_YES = 1,
717 	TRI_MODULE = 2,
718 };
719 
720 #ifdef __cplusplus
721 } /* extern "C" */
722 #endif
723 
724 #endif /* __LIBBPF_LIBBPF_H */
725