xref: /linux/tools/lib/bpf/libbpf.h (revision eb9928bed003dd61a443d0ba51ae066429fbe735)
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 	/* process CO-RE relocations non-strictly, allowing them to fail */
81 	bool relaxed_core_relocs;
82 	/* maps that set the 'pinning' attribute in their definition will have
83 	 * their pin_path attribute set to a file in this directory, and be
84 	 * auto-pinned to that path on load; defaults to "/sys/fs/bpf".
85 	 */
86 	const char *pin_root_path;
87 	__u32 attach_prog_fd;
88 	/* Additional kernel config content that augments and overrides
89 	 * system Kconfig for CONFIG_xxx externs.
90 	 */
91 	const char *kconfig;
92 };
93 #define bpf_object_open_opts__last_field kconfig
94 
95 LIBBPF_API struct bpf_object *bpf_object__open(const char *path);
96 LIBBPF_API struct bpf_object *
97 bpf_object__open_file(const char *path, const struct bpf_object_open_opts *opts);
98 LIBBPF_API struct bpf_object *
99 bpf_object__open_mem(const void *obj_buf, size_t obj_buf_sz,
100 		     const struct bpf_object_open_opts *opts);
101 
102 /* deprecated bpf_object__open variants */
103 LIBBPF_API struct bpf_object *
104 bpf_object__open_buffer(const void *obj_buf, size_t obj_buf_sz,
105 			const char *name);
106 LIBBPF_API struct bpf_object *
107 bpf_object__open_xattr(struct bpf_object_open_attr *attr);
108 
109 enum libbpf_pin_type {
110 	LIBBPF_PIN_NONE,
111 	/* PIN_BY_NAME: pin maps by name (in /sys/fs/bpf by default) */
112 	LIBBPF_PIN_BY_NAME,
113 };
114 
115 /* pin_maps and unpin_maps can both be called with a NULL path, in which case
116  * they will use the pin_path attribute of each map (and ignore all maps that
117  * don't have a pin_path set).
118  */
119 LIBBPF_API int bpf_object__pin_maps(struct bpf_object *obj, const char *path);
120 LIBBPF_API int bpf_object__unpin_maps(struct bpf_object *obj,
121 				      const char *path);
122 LIBBPF_API int bpf_object__pin_programs(struct bpf_object *obj,
123 					const char *path);
124 LIBBPF_API int bpf_object__unpin_programs(struct bpf_object *obj,
125 					  const char *path);
126 LIBBPF_API int bpf_object__pin(struct bpf_object *object, const char *path);
127 LIBBPF_API void bpf_object__close(struct bpf_object *object);
128 
129 struct bpf_object_load_attr {
130 	struct bpf_object *obj;
131 	int log_level;
132 	const char *target_btf_path;
133 };
134 
135 /* Load/unload object into/from kernel */
136 LIBBPF_API int bpf_object__load(struct bpf_object *obj);
137 LIBBPF_API int bpf_object__load_xattr(struct bpf_object_load_attr *attr);
138 LIBBPF_API int bpf_object__unload(struct bpf_object *obj);
139 
140 LIBBPF_API const char *bpf_object__name(const struct bpf_object *obj);
141 LIBBPF_API unsigned int bpf_object__kversion(const struct bpf_object *obj);
142 
143 struct btf;
144 LIBBPF_API struct btf *bpf_object__btf(const struct bpf_object *obj);
145 LIBBPF_API int bpf_object__btf_fd(const struct bpf_object *obj);
146 
147 LIBBPF_API struct bpf_program *
148 bpf_object__find_program_by_title(const struct bpf_object *obj,
149 				  const char *title);
150 LIBBPF_API struct bpf_program *
151 bpf_object__find_program_by_name(const struct bpf_object *obj,
152 				 const char *name);
153 
154 LIBBPF_API struct bpf_object *bpf_object__next(struct bpf_object *prev);
155 #define bpf_object__for_each_safe(pos, tmp)			\
156 	for ((pos) = bpf_object__next(NULL),		\
157 		(tmp) = bpf_object__next(pos);		\
158 	     (pos) != NULL;				\
159 	     (pos) = (tmp), (tmp) = bpf_object__next(tmp))
160 
161 typedef void (*bpf_object_clear_priv_t)(struct bpf_object *, void *);
162 LIBBPF_API int bpf_object__set_priv(struct bpf_object *obj, void *priv,
163 				    bpf_object_clear_priv_t clear_priv);
164 LIBBPF_API void *bpf_object__priv(const struct bpf_object *prog);
165 
166 LIBBPF_API int
167 libbpf_prog_type_by_name(const char *name, enum bpf_prog_type *prog_type,
168 			 enum bpf_attach_type *expected_attach_type);
169 LIBBPF_API int libbpf_attach_type_by_name(const char *name,
170 					  enum bpf_attach_type *attach_type);
171 LIBBPF_API int libbpf_find_vmlinux_btf_id(const char *name,
172 					  enum bpf_attach_type attach_type);
173 
174 /* Accessors of bpf_program */
175 struct bpf_program;
176 LIBBPF_API struct bpf_program *bpf_program__next(struct bpf_program *prog,
177 						 const struct bpf_object *obj);
178 
179 #define bpf_object__for_each_program(pos, obj)		\
180 	for ((pos) = bpf_program__next(NULL, (obj));	\
181 	     (pos) != NULL;				\
182 	     (pos) = bpf_program__next((pos), (obj)))
183 
184 LIBBPF_API struct bpf_program *bpf_program__prev(struct bpf_program *prog,
185 						 const struct bpf_object *obj);
186 
187 typedef void (*bpf_program_clear_priv_t)(struct bpf_program *, void *);
188 
189 LIBBPF_API int bpf_program__set_priv(struct bpf_program *prog, void *priv,
190 				     bpf_program_clear_priv_t clear_priv);
191 
192 LIBBPF_API void *bpf_program__priv(const struct bpf_program *prog);
193 LIBBPF_API void bpf_program__set_ifindex(struct bpf_program *prog,
194 					 __u32 ifindex);
195 
196 LIBBPF_API const char *bpf_program__name(const struct bpf_program *prog);
197 LIBBPF_API const char *bpf_program__title(const struct bpf_program *prog,
198 					  bool needs_copy);
199 
200 /* returns program size in bytes */
201 LIBBPF_API size_t bpf_program__size(const struct bpf_program *prog);
202 
203 LIBBPF_API int bpf_program__load(struct bpf_program *prog, char *license,
204 				 __u32 kern_version);
205 LIBBPF_API int bpf_program__fd(const struct bpf_program *prog);
206 LIBBPF_API int bpf_program__pin_instance(struct bpf_program *prog,
207 					 const char *path,
208 					 int instance);
209 LIBBPF_API int bpf_program__unpin_instance(struct bpf_program *prog,
210 					   const char *path,
211 					   int instance);
212 LIBBPF_API int bpf_program__pin(struct bpf_program *prog, const char *path);
213 LIBBPF_API int bpf_program__unpin(struct bpf_program *prog, const char *path);
214 LIBBPF_API void bpf_program__unload(struct bpf_program *prog);
215 
216 struct bpf_link;
217 
218 LIBBPF_API void bpf_link__disconnect(struct bpf_link *link);
219 LIBBPF_API int bpf_link__destroy(struct bpf_link *link);
220 
221 LIBBPF_API struct bpf_link *
222 bpf_program__attach(struct bpf_program *prog);
223 LIBBPF_API struct bpf_link *
224 bpf_program__attach_perf_event(struct bpf_program *prog, int pfd);
225 LIBBPF_API struct bpf_link *
226 bpf_program__attach_kprobe(struct bpf_program *prog, bool retprobe,
227 			   const char *func_name);
228 LIBBPF_API struct bpf_link *
229 bpf_program__attach_uprobe(struct bpf_program *prog, bool retprobe,
230 			   pid_t pid, const char *binary_path,
231 			   size_t func_offset);
232 LIBBPF_API struct bpf_link *
233 bpf_program__attach_tracepoint(struct bpf_program *prog,
234 			       const char *tp_category,
235 			       const char *tp_name);
236 LIBBPF_API struct bpf_link *
237 bpf_program__attach_raw_tracepoint(struct bpf_program *prog,
238 				   const char *tp_name);
239 
240 LIBBPF_API struct bpf_link *
241 bpf_program__attach_trace(struct bpf_program *prog);
242 struct bpf_insn;
243 
244 /*
245  * Libbpf allows callers to adjust BPF programs before being loaded
246  * into kernel. One program in an object file can be transformed into
247  * multiple variants to be attached to different hooks.
248  *
249  * bpf_program_prep_t, bpf_program__set_prep and bpf_program__nth_fd
250  * form an API for this purpose.
251  *
252  * - bpf_program_prep_t:
253  *   Defines a 'preprocessor', which is a caller defined function
254  *   passed to libbpf through bpf_program__set_prep(), and will be
255  *   called before program is loaded. The processor should adjust
256  *   the program one time for each instance according to the instance id
257  *   passed to it.
258  *
259  * - bpf_program__set_prep:
260  *   Attaches a preprocessor to a BPF program. The number of instances
261  *   that should be created is also passed through this function.
262  *
263  * - bpf_program__nth_fd:
264  *   After the program is loaded, get resulting FD of a given instance
265  *   of the BPF program.
266  *
267  * If bpf_program__set_prep() is not used, the program would be loaded
268  * without adjustment during bpf_object__load(). The program has only
269  * one instance. In this case bpf_program__fd(prog) is equal to
270  * bpf_program__nth_fd(prog, 0).
271  */
272 
273 struct bpf_prog_prep_result {
274 	/*
275 	 * If not NULL, load new instruction array.
276 	 * If set to NULL, don't load this instance.
277 	 */
278 	struct bpf_insn *new_insn_ptr;
279 	int new_insn_cnt;
280 
281 	/* If not NULL, result FD is written to it. */
282 	int *pfd;
283 };
284 
285 /*
286  * Parameters of bpf_program_prep_t:
287  *  - prog:	The bpf_program being loaded.
288  *  - n:	Index of instance being generated.
289  *  - insns:	BPF instructions array.
290  *  - insns_cnt:Number of instructions in insns.
291  *  - res:	Output parameter, result of transformation.
292  *
293  * Return value:
294  *  - Zero:	pre-processing success.
295  *  - Non-zero:	pre-processing error, stop loading.
296  */
297 typedef int (*bpf_program_prep_t)(struct bpf_program *prog, int n,
298 				  struct bpf_insn *insns, int insns_cnt,
299 				  struct bpf_prog_prep_result *res);
300 
301 LIBBPF_API int bpf_program__set_prep(struct bpf_program *prog, int nr_instance,
302 				     bpf_program_prep_t prep);
303 
304 LIBBPF_API int bpf_program__nth_fd(const struct bpf_program *prog, int n);
305 
306 /*
307  * Adjust type of BPF program. Default is kprobe.
308  */
309 LIBBPF_API int bpf_program__set_socket_filter(struct bpf_program *prog);
310 LIBBPF_API int bpf_program__set_tracepoint(struct bpf_program *prog);
311 LIBBPF_API int bpf_program__set_raw_tracepoint(struct bpf_program *prog);
312 LIBBPF_API int bpf_program__set_kprobe(struct bpf_program *prog);
313 LIBBPF_API int bpf_program__set_sched_cls(struct bpf_program *prog);
314 LIBBPF_API int bpf_program__set_sched_act(struct bpf_program *prog);
315 LIBBPF_API int bpf_program__set_xdp(struct bpf_program *prog);
316 LIBBPF_API int bpf_program__set_perf_event(struct bpf_program *prog);
317 LIBBPF_API int bpf_program__set_tracing(struct bpf_program *prog);
318 
319 LIBBPF_API enum bpf_prog_type bpf_program__get_type(struct bpf_program *prog);
320 LIBBPF_API void bpf_program__set_type(struct bpf_program *prog,
321 				      enum bpf_prog_type type);
322 
323 LIBBPF_API enum bpf_attach_type
324 bpf_program__get_expected_attach_type(struct bpf_program *prog);
325 LIBBPF_API void
326 bpf_program__set_expected_attach_type(struct bpf_program *prog,
327 				      enum bpf_attach_type type);
328 
329 LIBBPF_API bool bpf_program__is_socket_filter(const struct bpf_program *prog);
330 LIBBPF_API bool bpf_program__is_tracepoint(const struct bpf_program *prog);
331 LIBBPF_API bool bpf_program__is_raw_tracepoint(const struct bpf_program *prog);
332 LIBBPF_API bool bpf_program__is_kprobe(const struct bpf_program *prog);
333 LIBBPF_API bool bpf_program__is_sched_cls(const struct bpf_program *prog);
334 LIBBPF_API bool bpf_program__is_sched_act(const struct bpf_program *prog);
335 LIBBPF_API bool bpf_program__is_xdp(const struct bpf_program *prog);
336 LIBBPF_API bool bpf_program__is_perf_event(const struct bpf_program *prog);
337 LIBBPF_API bool bpf_program__is_tracing(const struct bpf_program *prog);
338 
339 /*
340  * No need for __attribute__((packed)), all members of 'bpf_map_def'
341  * are all aligned.  In addition, using __attribute__((packed))
342  * would trigger a -Wpacked warning message, and lead to an error
343  * if -Werror is set.
344  */
345 struct bpf_map_def {
346 	unsigned int type;
347 	unsigned int key_size;
348 	unsigned int value_size;
349 	unsigned int max_entries;
350 	unsigned int map_flags;
351 };
352 
353 /*
354  * The 'struct bpf_map' in include/linux/bpf.h is internal to the kernel,
355  * so no need to worry about a name clash.
356  */
357 struct bpf_map;
358 LIBBPF_API struct bpf_map *
359 bpf_object__find_map_by_name(const struct bpf_object *obj, const char *name);
360 
361 LIBBPF_API int
362 bpf_object__find_map_fd_by_name(const struct bpf_object *obj, const char *name);
363 
364 /*
365  * Get bpf_map through the offset of corresponding struct bpf_map_def
366  * in the BPF object file.
367  */
368 LIBBPF_API struct bpf_map *
369 bpf_object__find_map_by_offset(struct bpf_object *obj, size_t offset);
370 
371 LIBBPF_API struct bpf_map *
372 bpf_map__next(const struct bpf_map *map, const struct bpf_object *obj);
373 #define bpf_object__for_each_map(pos, obj)		\
374 	for ((pos) = bpf_map__next(NULL, (obj));	\
375 	     (pos) != NULL;				\
376 	     (pos) = bpf_map__next((pos), (obj)))
377 #define bpf_map__for_each bpf_object__for_each_map
378 
379 LIBBPF_API struct bpf_map *
380 bpf_map__prev(const struct bpf_map *map, const struct bpf_object *obj);
381 
382 LIBBPF_API int bpf_map__fd(const struct bpf_map *map);
383 LIBBPF_API const struct bpf_map_def *bpf_map__def(const struct bpf_map *map);
384 LIBBPF_API const char *bpf_map__name(const struct bpf_map *map);
385 LIBBPF_API __u32 bpf_map__btf_key_type_id(const struct bpf_map *map);
386 LIBBPF_API __u32 bpf_map__btf_value_type_id(const struct bpf_map *map);
387 
388 typedef void (*bpf_map_clear_priv_t)(struct bpf_map *, void *);
389 LIBBPF_API int bpf_map__set_priv(struct bpf_map *map, void *priv,
390 				 bpf_map_clear_priv_t clear_priv);
391 LIBBPF_API void *bpf_map__priv(const struct bpf_map *map);
392 LIBBPF_API int bpf_map__reuse_fd(struct bpf_map *map, int fd);
393 LIBBPF_API int bpf_map__resize(struct bpf_map *map, __u32 max_entries);
394 LIBBPF_API bool bpf_map__is_offload_neutral(const struct bpf_map *map);
395 LIBBPF_API bool bpf_map__is_internal(const struct bpf_map *map);
396 LIBBPF_API void bpf_map__set_ifindex(struct bpf_map *map, __u32 ifindex);
397 LIBBPF_API int bpf_map__set_pin_path(struct bpf_map *map, const char *path);
398 LIBBPF_API const char *bpf_map__get_pin_path(const struct bpf_map *map);
399 LIBBPF_API bool bpf_map__is_pinned(const struct bpf_map *map);
400 LIBBPF_API int bpf_map__pin(struct bpf_map *map, const char *path);
401 LIBBPF_API int bpf_map__unpin(struct bpf_map *map, const char *path);
402 
403 LIBBPF_API int bpf_map__set_inner_map_fd(struct bpf_map *map, int fd);
404 
405 LIBBPF_API long libbpf_get_error(const void *ptr);
406 
407 struct bpf_prog_load_attr {
408 	const char *file;
409 	enum bpf_prog_type prog_type;
410 	enum bpf_attach_type expected_attach_type;
411 	int ifindex;
412 	int log_level;
413 	int prog_flags;
414 };
415 
416 LIBBPF_API int bpf_prog_load_xattr(const struct bpf_prog_load_attr *attr,
417 				   struct bpf_object **pobj, int *prog_fd);
418 LIBBPF_API int bpf_prog_load(const char *file, enum bpf_prog_type type,
419 			     struct bpf_object **pobj, int *prog_fd);
420 
421 struct xdp_link_info {
422 	__u32 prog_id;
423 	__u32 drv_prog_id;
424 	__u32 hw_prog_id;
425 	__u32 skb_prog_id;
426 	__u8 attach_mode;
427 };
428 
429 LIBBPF_API int bpf_set_link_xdp_fd(int ifindex, int fd, __u32 flags);
430 LIBBPF_API int bpf_get_link_xdp_id(int ifindex, __u32 *prog_id, __u32 flags);
431 LIBBPF_API int bpf_get_link_xdp_info(int ifindex, struct xdp_link_info *info,
432 				     size_t info_size, __u32 flags);
433 
434 struct perf_buffer;
435 
436 typedef void (*perf_buffer_sample_fn)(void *ctx, int cpu,
437 				      void *data, __u32 size);
438 typedef void (*perf_buffer_lost_fn)(void *ctx, int cpu, __u64 cnt);
439 
440 /* common use perf buffer options */
441 struct perf_buffer_opts {
442 	/* if specified, sample_cb is called for each sample */
443 	perf_buffer_sample_fn sample_cb;
444 	/* if specified, lost_cb is called for each batch of lost samples */
445 	perf_buffer_lost_fn lost_cb;
446 	/* ctx is provided to sample_cb and lost_cb */
447 	void *ctx;
448 };
449 
450 LIBBPF_API struct perf_buffer *
451 perf_buffer__new(int map_fd, size_t page_cnt,
452 		 const struct perf_buffer_opts *opts);
453 
454 enum bpf_perf_event_ret {
455 	LIBBPF_PERF_EVENT_DONE	= 0,
456 	LIBBPF_PERF_EVENT_ERROR	= -1,
457 	LIBBPF_PERF_EVENT_CONT	= -2,
458 };
459 
460 struct perf_event_header;
461 
462 typedef enum bpf_perf_event_ret
463 (*perf_buffer_event_fn)(void *ctx, int cpu, struct perf_event_header *event);
464 
465 /* raw perf buffer options, giving most power and control */
466 struct perf_buffer_raw_opts {
467 	/* perf event attrs passed directly into perf_event_open() */
468 	struct perf_event_attr *attr;
469 	/* raw event callback */
470 	perf_buffer_event_fn event_cb;
471 	/* ctx is provided to event_cb */
472 	void *ctx;
473 	/* if cpu_cnt == 0, open all on all possible CPUs (up to the number of
474 	 * max_entries of given PERF_EVENT_ARRAY map)
475 	 */
476 	int cpu_cnt;
477 	/* if cpu_cnt > 0, cpus is an array of CPUs to open ring buffers on */
478 	int *cpus;
479 	/* if cpu_cnt > 0, map_keys specify map keys to set per-CPU FDs for */
480 	int *map_keys;
481 };
482 
483 LIBBPF_API struct perf_buffer *
484 perf_buffer__new_raw(int map_fd, size_t page_cnt,
485 		     const struct perf_buffer_raw_opts *opts);
486 
487 LIBBPF_API void perf_buffer__free(struct perf_buffer *pb);
488 LIBBPF_API int perf_buffer__poll(struct perf_buffer *pb, int timeout_ms);
489 
490 typedef enum bpf_perf_event_ret
491 	(*bpf_perf_event_print_t)(struct perf_event_header *hdr,
492 				  void *private_data);
493 LIBBPF_API enum bpf_perf_event_ret
494 bpf_perf_event_read_simple(void *mmap_mem, size_t mmap_size, size_t page_size,
495 			   void **copy_mem, size_t *copy_size,
496 			   bpf_perf_event_print_t fn, void *private_data);
497 
498 struct bpf_prog_linfo;
499 struct bpf_prog_info;
500 
501 LIBBPF_API void bpf_prog_linfo__free(struct bpf_prog_linfo *prog_linfo);
502 LIBBPF_API struct bpf_prog_linfo *
503 bpf_prog_linfo__new(const struct bpf_prog_info *info);
504 LIBBPF_API const struct bpf_line_info *
505 bpf_prog_linfo__lfind_addr_func(const struct bpf_prog_linfo *prog_linfo,
506 				__u64 addr, __u32 func_idx, __u32 nr_skip);
507 LIBBPF_API const struct bpf_line_info *
508 bpf_prog_linfo__lfind(const struct bpf_prog_linfo *prog_linfo,
509 		      __u32 insn_off, __u32 nr_skip);
510 
511 /*
512  * Probe for supported system features
513  *
514  * Note that running many of these probes in a short amount of time can cause
515  * the kernel to reach the maximal size of lockable memory allowed for the
516  * user, causing subsequent probes to fail. In this case, the caller may want
517  * to adjust that limit with setrlimit().
518  */
519 LIBBPF_API bool bpf_probe_prog_type(enum bpf_prog_type prog_type,
520 				    __u32 ifindex);
521 LIBBPF_API bool bpf_probe_map_type(enum bpf_map_type map_type, __u32 ifindex);
522 LIBBPF_API bool bpf_probe_helper(enum bpf_func_id id,
523 				 enum bpf_prog_type prog_type, __u32 ifindex);
524 
525 /*
526  * Get bpf_prog_info in continuous memory
527  *
528  * struct bpf_prog_info has multiple arrays. The user has option to choose
529  * arrays to fetch from kernel. The following APIs provide an uniform way to
530  * fetch these data. All arrays in bpf_prog_info are stored in a single
531  * continuous memory region. This makes it easy to store the info in a
532  * file.
533  *
534  * Before writing bpf_prog_info_linear to files, it is necessary to
535  * translate pointers in bpf_prog_info to offsets. Helper functions
536  * bpf_program__bpil_addr_to_offs() and bpf_program__bpil_offs_to_addr()
537  * are introduced to switch between pointers and offsets.
538  *
539  * Examples:
540  *   # To fetch map_ids and prog_tags:
541  *   __u64 arrays = (1UL << BPF_PROG_INFO_MAP_IDS) |
542  *           (1UL << BPF_PROG_INFO_PROG_TAGS);
543  *   struct bpf_prog_info_linear *info_linear =
544  *           bpf_program__get_prog_info_linear(fd, arrays);
545  *
546  *   # To save data in file
547  *   bpf_program__bpil_addr_to_offs(info_linear);
548  *   write(f, info_linear, sizeof(*info_linear) + info_linear->data_len);
549  *
550  *   # To read data from file
551  *   read(f, info_linear, <proper_size>);
552  *   bpf_program__bpil_offs_to_addr(info_linear);
553  */
554 enum bpf_prog_info_array {
555 	BPF_PROG_INFO_FIRST_ARRAY = 0,
556 	BPF_PROG_INFO_JITED_INSNS = 0,
557 	BPF_PROG_INFO_XLATED_INSNS,
558 	BPF_PROG_INFO_MAP_IDS,
559 	BPF_PROG_INFO_JITED_KSYMS,
560 	BPF_PROG_INFO_JITED_FUNC_LENS,
561 	BPF_PROG_INFO_FUNC_INFO,
562 	BPF_PROG_INFO_LINE_INFO,
563 	BPF_PROG_INFO_JITED_LINE_INFO,
564 	BPF_PROG_INFO_PROG_TAGS,
565 	BPF_PROG_INFO_LAST_ARRAY,
566 };
567 
568 struct bpf_prog_info_linear {
569 	/* size of struct bpf_prog_info, when the tool is compiled */
570 	__u32			info_len;
571 	/* total bytes allocated for data, round up to 8 bytes */
572 	__u32			data_len;
573 	/* which arrays are included in data */
574 	__u64			arrays;
575 	struct bpf_prog_info	info;
576 	__u8			data[];
577 };
578 
579 LIBBPF_API struct bpf_prog_info_linear *
580 bpf_program__get_prog_info_linear(int fd, __u64 arrays);
581 
582 LIBBPF_API void
583 bpf_program__bpil_addr_to_offs(struct bpf_prog_info_linear *info_linear);
584 
585 LIBBPF_API void
586 bpf_program__bpil_offs_to_addr(struct bpf_prog_info_linear *info_linear);
587 
588 /*
589  * A helper function to get the number of possible CPUs before looking up
590  * per-CPU maps. Negative errno is returned on failure.
591  *
592  * Example usage:
593  *
594  *     int ncpus = libbpf_num_possible_cpus();
595  *     if (ncpus < 0) {
596  *          // error handling
597  *     }
598  *     long values[ncpus];
599  *     bpf_map_lookup_elem(per_cpu_map_fd, key, values);
600  *
601  */
602 LIBBPF_API int libbpf_num_possible_cpus(void);
603 
604 struct bpf_map_skeleton {
605 	const char *name;
606 	struct bpf_map **map;
607 	void **mmaped;
608 };
609 
610 struct bpf_prog_skeleton {
611 	const char *name;
612 	struct bpf_program **prog;
613 	struct bpf_link **link;
614 };
615 
616 struct bpf_object_skeleton {
617 	size_t sz; /* size of this struct, for forward/backward compatibility */
618 
619 	const char *name;
620 	void *data;
621 	size_t data_sz;
622 
623 	struct bpf_object **obj;
624 
625 	int map_cnt;
626 	int map_skel_sz; /* sizeof(struct bpf_skeleton_map) */
627 	struct bpf_map_skeleton *maps;
628 
629 	int prog_cnt;
630 	int prog_skel_sz; /* sizeof(struct bpf_skeleton_prog) */
631 	struct bpf_prog_skeleton *progs;
632 };
633 
634 LIBBPF_API int
635 bpf_object__open_skeleton(struct bpf_object_skeleton *s,
636 			  const struct bpf_object_open_opts *opts);
637 LIBBPF_API int bpf_object__load_skeleton(struct bpf_object_skeleton *s);
638 LIBBPF_API int bpf_object__attach_skeleton(struct bpf_object_skeleton *s);
639 LIBBPF_API void bpf_object__detach_skeleton(struct bpf_object_skeleton *s);
640 LIBBPF_API void bpf_object__destroy_skeleton(struct bpf_object_skeleton *s);
641 
642 enum libbpf_tristate {
643 	TRI_NO = 0,
644 	TRI_YES = 1,
645 	TRI_MODULE = 2,
646 };
647 
648 #ifdef __cplusplus
649 } /* extern "C" */
650 #endif
651 
652 #endif /* __LIBBPF_LIBBPF_H */
653