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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#include "libbpf_legacy.h"
22
23#ifdef __cplusplus
24extern "C" {
25#endif
26
27/**
28 * @brief **libbpf_major_version()** provides the major version of libbpf.
29 * @return An integer, the major version number
30 */
31LIBBPF_API __u32 libbpf_major_version(void);
32
33/**
34 * @brief **libbpf_minor_version()** provides the minor version of libbpf.
35 * @return An integer, the minor version number
36 */
37LIBBPF_API __u32 libbpf_minor_version(void);
38
39/**
40 * @brief **libbpf_version_string()** provides the version of libbpf in a
41 * human-readable form, e.g., "v1.7".
42 * @return Pointer to a static string containing the version
43 *
44 * The format is *not* a part of a stable API and may change in the future.
45 */
46LIBBPF_API const char *libbpf_version_string(void);
47
48enum libbpf_errno {
49 __LIBBPF_ERRNO__START = 4000,
50
51 /* Something wrong in libelf */
52 LIBBPF_ERRNO__LIBELF = __LIBBPF_ERRNO__START,
53 LIBBPF_ERRNO__FORMAT, /* BPF object format invalid */
54 LIBBPF_ERRNO__KVERSION, /* Incorrect or no 'version' section */
55 LIBBPF_ERRNO__ENDIAN, /* Endian mismatch */
56 LIBBPF_ERRNO__INTERNAL, /* Internal error in libbpf */
57 LIBBPF_ERRNO__RELOC, /* Relocation failed */
58 LIBBPF_ERRNO__LOAD, /* Load program failure for unknown reason */
59 LIBBPF_ERRNO__VERIFY, /* Kernel verifier blocks program loading */
60 LIBBPF_ERRNO__PROG2BIG, /* Program too big */
61 LIBBPF_ERRNO__KVER, /* Incorrect kernel version */
62 LIBBPF_ERRNO__PROGTYPE, /* Kernel doesn't support this program type */
63 LIBBPF_ERRNO__WRNGPID, /* Wrong pid in netlink message */
64 LIBBPF_ERRNO__INVSEQ, /* Invalid netlink sequence */
65 LIBBPF_ERRNO__NLPARSE, /* netlink parsing error */
66 __LIBBPF_ERRNO__END,
67};
68
69/**
70 * @brief **libbpf_strerror()** converts the provided error code into a
71 * human-readable string.
72 * @param err The error code to convert
73 * @param buf Pointer to a buffer where the error message will be stored
74 * @param size The number of bytes in the buffer
75 * @return 0, on success; negative error code, otherwise
76 */
77LIBBPF_API int libbpf_strerror(int err, char *buf, size_t size);
78
79/**
80 * @brief **libbpf_bpf_attach_type_str()** converts the provided attach type
81 * value into a textual representation.
82 * @param t The attach type.
83 * @return Pointer to a static string identifying the attach type. NULL is
84 * returned for unknown **bpf_attach_type** values.
85 */
86LIBBPF_API const char *libbpf_bpf_attach_type_str(enum bpf_attach_type t);
87
88/**
89 * @brief **libbpf_bpf_link_type_str()** converts the provided link type value
90 * into a textual representation.
91 * @param t The link type.
92 * @return Pointer to a static string identifying the link type. NULL is
93 * returned for unknown **bpf_link_type** values.
94 */
95LIBBPF_API const char *libbpf_bpf_link_type_str(enum bpf_link_type t);
96
97/**
98 * @brief **libbpf_bpf_map_type_str()** converts the provided map type value
99 * into a textual representation.
100 * @param t The map type.
101 * @return Pointer to a static string identifying the map type. NULL is
102 * returned for unknown **bpf_map_type** values.
103 */
104LIBBPF_API const char *libbpf_bpf_map_type_str(enum bpf_map_type t);
105
106/**
107 * @brief **libbpf_bpf_prog_type_str()** converts the provided program type
108 * value into a textual representation.
109 * @param t The program type.
110 * @return Pointer to a static string identifying the program type. NULL is
111 * returned for unknown **bpf_prog_type** values.
112 */
113LIBBPF_API const char *libbpf_bpf_prog_type_str(enum bpf_prog_type t);
114
115enum libbpf_print_level {
116 LIBBPF_WARN,
117 LIBBPF_INFO,
118 LIBBPF_DEBUG,
119};
120
121typedef int (*libbpf_print_fn_t)(enum libbpf_print_level level,
122 const char *, va_list ap);
123
124/**
125 * @brief **libbpf_set_print()** sets user-provided log callback function to
126 * be used for libbpf warnings and informational messages. If the user callback
127 * is not set, messages are logged to stderr by default. The verbosity of these
128 * messages can be controlled by setting the environment variable
129 * LIBBPF_LOG_LEVEL to either warn, info, or debug.
130 * @param fn The log print function. If NULL, libbpf won't print anything.
131 * @return Pointer to old print function.
132 *
133 * This function is thread-safe.
134 */
135LIBBPF_API libbpf_print_fn_t libbpf_set_print(libbpf_print_fn_t fn);
136
137/* Hide internal to user */
138struct bpf_object;
139
140struct bpf_object_open_opts {
141 /* size of this struct, for forward/backward compatibility */
142 size_t sz;
143 /* object name override, if provided:
144 * - for object open from file, this will override setting object
145 * name from file path's base name;
146 * - for object open from memory buffer, this will specify an object
147 * name and will override default "<addr>-<buf-size>" name;
148 */
149 const char *object_name;
150 /* parse map definitions non-strictly, allowing extra attributes/data */
151 bool relaxed_maps;
152 /* maps that set the 'pinning' attribute in their definition will have
153 * their pin_path attribute set to a file in this directory, and be
154 * auto-pinned to that path on load; defaults to "/sys/fs/bpf".
155 */
156 const char *pin_root_path;
157
158 __u32 :32; /* stub out now removed attach_prog_fd */
159
160 /* Additional kernel config content that augments and overrides
161 * system Kconfig for CONFIG_xxx externs.
162 */
163 const char *kconfig;
164 /* Path to the custom BTF to be used for BPF CO-RE relocations.
165 * This custom BTF completely replaces the use of vmlinux BTF
166 * for the purpose of CO-RE relocations.
167 * NOTE: any other BPF feature (e.g., fentry/fexit programs,
168 * struct_ops, etc) will need actual kernel BTF at /sys/kernel/btf/vmlinux.
169 */
170 const char *btf_custom_path;
171 /* Pointer to a buffer for storing kernel logs for applicable BPF
172 * commands. Valid kernel_log_size has to be specified as well and are
173 * passed-through to bpf() syscall. Keep in mind that kernel might
174 * fail operation with -ENOSPC error if provided buffer is too small
175 * to contain entire log output.
176 * See the comment below for kernel_log_level for interaction between
177 * log_buf and log_level settings.
178 *
179 * If specified, this log buffer will be passed for:
180 * - each BPF progral load (BPF_PROG_LOAD) attempt, unless overridden
181 * with bpf_program__set_log() on per-program level, to get
182 * BPF verifier log output.
183 * - during BPF object's BTF load into kernel (BPF_BTF_LOAD) to get
184 * BTF sanity checking log.
185 *
186 * Each BPF command (BPF_BTF_LOAD or BPF_PROG_LOAD) will overwrite
187 * previous contents, so if you need more fine-grained control, set
188 * per-program buffer with bpf_program__set_log_buf() to preserve each
189 * individual program's verification log. Keep using kernel_log_buf
190 * for BTF verification log, if necessary.
191 */
192 char *kernel_log_buf;
193 size_t kernel_log_size;
194 /*
195 * Log level can be set independently from log buffer. Log_level=0
196 * means that libbpf will attempt loading BTF or program without any
197 * logging requested, but will retry with either its own or custom log
198 * buffer, if provided, and log_level=1 on any error.
199 * And vice versa, setting log_level>0 will request BTF or prog
200 * loading with verbose log from the first attempt (and as such also
201 * for successfully loaded BTF or program), and the actual log buffer
202 * could be either libbpf's own auto-allocated log buffer, if
203 * kernel_log_buffer is NULL, or user-provided custom kernel_log_buf.
204 * If user didn't provide custom log buffer, libbpf will emit captured
205 * logs through its print callback.
206 */
207 __u32 kernel_log_level;
208 /* Path to BPF FS mount point to derive BPF token from.
209 *
210 * Created BPF token will be used for all bpf() syscall operations
211 * that accept BPF token (e.g., map creation, BTF and program loads,
212 * etc) automatically within instantiated BPF object.
213 *
214 * If bpf_token_path is not specified, libbpf will consult
215 * LIBBPF_BPF_TOKEN_PATH environment variable. If set, it will be
216 * taken as a value of bpf_token_path option and will force libbpf to
217 * either create BPF token from provided custom BPF FS path, or will
218 * disable implicit BPF token creation, if envvar value is an empty
219 * string. bpf_token_path overrides LIBBPF_BPF_TOKEN_PATH, if both are
220 * set at the same time.
221 *
222 * Setting bpf_token_path option to empty string disables libbpf's
223 * automatic attempt to create BPF token from default BPF FS mount
224 * point (/sys/fs/bpf), in case this default behavior is undesirable.
225 */
226 const char *bpf_token_path;
227
228 size_t :0;
229};
230#define bpf_object_open_opts__last_field bpf_token_path
231
232/**
233 * @brief **bpf_object__open()** creates a bpf_object by opening
234 * the BPF ELF object file pointed to by the passed path and loading it
235 * into memory.
236 * @param path BPF object file path.
237 * @return pointer to the new bpf_object; or NULL is returned on error,
238 * error code is stored in errno
239 */
240LIBBPF_API struct bpf_object *bpf_object__open(const char *path);
241
242/**
243 * @brief **bpf_object__open_file()** creates a bpf_object by opening
244 * the BPF ELF object file pointed to by the passed path and loading it
245 * into memory.
246 * @param path BPF object file path
247 * @param opts options for how to load the bpf object, this parameter is
248 * optional and can be set to NULL
249 * @return pointer to the new bpf_object; or NULL is returned on error,
250 * error code is stored in errno
251 */
252LIBBPF_API struct bpf_object *
253bpf_object__open_file(const char *path, const struct bpf_object_open_opts *opts);
254
255/**
256 * @brief **bpf_object__open_mem()** creates a bpf_object by reading
257 * the BPF objects raw bytes from a memory buffer containing a valid
258 * BPF ELF object file.
259 * @param obj_buf pointer to the buffer containing ELF file bytes
260 * @param obj_buf_sz number of bytes in the buffer
261 * @param opts options for how to load the bpf object
262 * @return pointer to the new bpf_object; or NULL is returned on error,
263 * error code is stored in errno
264 */
265LIBBPF_API struct bpf_object *
266bpf_object__open_mem(const void *obj_buf, size_t obj_buf_sz,
267 const struct bpf_object_open_opts *opts);
268
269/**
270 * @brief **bpf_object__prepare()** prepares BPF object for loading:
271 * performs ELF processing, relocations, prepares final state of BPF program
272 * instructions (accessible with bpf_program__insns()), creates and
273 * (potentially) pins maps. Leaves BPF object in the state ready for program
274 * loading.
275 * @param obj Pointer to a valid BPF object instance returned by
276 * **bpf_object__open*()** API
277 * @return 0, on success; negative error code, otherwise, error code is
278 * stored in errno
279 */
280LIBBPF_API int bpf_object__prepare(struct bpf_object *obj);
281
282/**
283 * @brief **bpf_object__load()** loads BPF object into kernel.
284 * @param obj Pointer to a valid BPF object instance returned by
285 * **bpf_object__open*()** APIs
286 * @return 0, on success; negative error code, otherwise, error code is
287 * stored in errno
288 */
289LIBBPF_API int bpf_object__load(struct bpf_object *obj);
290
291/**
292 * @brief **bpf_object__close()** closes a BPF object and releases all
293 * resources.
294 * @param obj Pointer to a valid BPF object
295 */
296LIBBPF_API void bpf_object__close(struct bpf_object *obj);
297
298/**
299 * @brief **bpf_object__pin_maps()** pins each map contained within
300 * the BPF object at the passed directory.
301 * @param obj Pointer to a valid BPF object
302 * @param path A directory where maps should be pinned.
303 * @return 0, on success; negative error code, otherwise
304 *
305 * If `path` is NULL `bpf_map__pin` (which is being used on each map)
306 * will use the pin_path attribute of each map. In this case, maps that
307 * don't have a pin_path set will be ignored.
308 */
309LIBBPF_API int bpf_object__pin_maps(struct bpf_object *obj, const char *path);
310
311/**
312 * @brief **bpf_object__unpin_maps()** unpins each map contained within
313 * the BPF object found in the passed directory.
314 * @param obj Pointer to a valid BPF object
315 * @param path A directory where pinned maps should be searched for.
316 * @return 0, on success; negative error code, otherwise
317 *
318 * If `path` is NULL `bpf_map__unpin` (which is being used on each map)
319 * will use the pin_path attribute of each map. In this case, maps that
320 * don't have a pin_path set will be ignored.
321 */
322LIBBPF_API int bpf_object__unpin_maps(struct bpf_object *obj,
323 const char *path);
324LIBBPF_API int bpf_object__pin_programs(struct bpf_object *obj,
325 const char *path);
326LIBBPF_API int bpf_object__unpin_programs(struct bpf_object *obj,
327 const char *path);
328LIBBPF_API int bpf_object__pin(struct bpf_object *object, const char *path);
329LIBBPF_API int bpf_object__unpin(struct bpf_object *object, const char *path);
330
331LIBBPF_API const char *bpf_object__name(const struct bpf_object *obj);
332LIBBPF_API unsigned int bpf_object__kversion(const struct bpf_object *obj);
333LIBBPF_API int bpf_object__set_kversion(struct bpf_object *obj, __u32 kern_version);
334
335/**
336 * @brief **bpf_object__token_fd** is an accessor for BPF token FD associated
337 * with BPF object.
338 * @param obj Pointer to a valid BPF object
339 * @return BPF token FD or -1, if it wasn't set
340 */
341LIBBPF_API int bpf_object__token_fd(const struct bpf_object *obj);
342
343struct btf;
344LIBBPF_API struct btf *bpf_object__btf(const struct bpf_object *obj);
345LIBBPF_API int bpf_object__btf_fd(const struct bpf_object *obj);
346
347LIBBPF_API struct bpf_program *
348bpf_object__find_program_by_name(const struct bpf_object *obj,
349 const char *name);
350
351LIBBPF_API int
352libbpf_prog_type_by_name(const char *name, enum bpf_prog_type *prog_type,
353 enum bpf_attach_type *expected_attach_type);
354LIBBPF_API int libbpf_attach_type_by_name(const char *name,
355 enum bpf_attach_type *attach_type);
356LIBBPF_API int libbpf_find_vmlinux_btf_id(const char *name,
357 enum bpf_attach_type attach_type);
358
359/* Accessors of bpf_program */
360struct bpf_program;
361
362LIBBPF_API struct bpf_program *
363bpf_object__next_program(const struct bpf_object *obj, struct bpf_program *prog);
364
365#define bpf_object__for_each_program(pos, obj) \
366 for ((pos) = bpf_object__next_program((obj), NULL); \
367 (pos) != NULL; \
368 (pos) = bpf_object__next_program((obj), (pos)))
369
370LIBBPF_API struct bpf_program *
371bpf_object__prev_program(const struct bpf_object *obj, struct bpf_program *prog);
372
373LIBBPF_API void bpf_program__set_ifindex(struct bpf_program *prog,
374 __u32 ifindex);
375
376LIBBPF_API const char *bpf_program__name(const struct bpf_program *prog);
377LIBBPF_API const char *bpf_program__section_name(const struct bpf_program *prog);
378LIBBPF_API bool bpf_program__autoload(const struct bpf_program *prog);
379LIBBPF_API int bpf_program__set_autoload(struct bpf_program *prog, bool autoload);
380LIBBPF_API bool bpf_program__autoattach(const struct bpf_program *prog);
381LIBBPF_API void bpf_program__set_autoattach(struct bpf_program *prog, bool autoattach);
382
383struct bpf_insn;
384
385/**
386 * @brief **bpf_program__insns()** gives read-only access to BPF program's
387 * underlying BPF instructions.
388 * @param prog BPF program for which to return instructions
389 * @return a pointer to an array of BPF instructions that belong to the
390 * specified BPF program
391 *
392 * Returned pointer is always valid and not NULL. Number of `struct bpf_insn`
393 * pointed to can be fetched using **bpf_program__insn_cnt()** API.
394 *
395 * Keep in mind, libbpf can modify and append/delete BPF program's
396 * instructions as it processes BPF object file and prepares everything for
397 * uploading into the kernel. So depending on the point in BPF object
398 * lifetime, **bpf_program__insns()** can return different sets of
399 * instructions. As an example, during BPF object load phase BPF program
400 * instructions will be CO-RE-relocated, BPF subprograms instructions will be
401 * appended, ldimm64 instructions will have FDs embedded, etc. So instructions
402 * returned before **bpf_object__load()** and after it might be quite
403 * different.
404 */
405LIBBPF_API const struct bpf_insn *bpf_program__insns(const struct bpf_program *prog);
406
407/**
408 * @brief **bpf_program__set_insns()** can set BPF program's underlying
409 * BPF instructions.
410 *
411 * WARNING: This is a very advanced libbpf API and users need to know
412 * what they are doing. This should be used from prog_prepare_load_fn
413 * callback only.
414 *
415 * @param prog BPF program for which to return instructions
416 * @param new_insns a pointer to an array of BPF instructions
417 * @param new_insn_cnt number of `struct bpf_insn`'s that form
418 * specified BPF program
419 * @return 0, on success; negative error code, otherwise
420 */
421LIBBPF_API int bpf_program__set_insns(struct bpf_program *prog,
422 struct bpf_insn *new_insns, size_t new_insn_cnt);
423
424/**
425 * @brief **bpf_program__insn_cnt()** returns number of `struct bpf_insn`'s
426 * that form specified BPF program.
427 * @param prog BPF program for which to return number of BPF instructions
428 *
429 * See **bpf_program__insns()** documentation for notes on how libbpf can
430 * change instructions and their count during different phases of
431 * **bpf_object** lifetime.
432 */
433LIBBPF_API size_t bpf_program__insn_cnt(const struct bpf_program *prog);
434
435LIBBPF_API int bpf_program__fd(const struct bpf_program *prog);
436
437/**
438 * @brief **bpf_program__pin()** pins the BPF program to a file
439 * in the BPF FS specified by a path. This increments the programs
440 * reference count, allowing it to stay loaded after the process
441 * which loaded it has exited.
442 *
443 * @param prog BPF program to pin, must already be loaded
444 * @param path file path in a BPF file system
445 * @return 0, on success; negative error code, otherwise
446 */
447LIBBPF_API int bpf_program__pin(struct bpf_program *prog, const char *path);
448
449/**
450 * @brief **bpf_program__unpin()** unpins the BPF program from a file
451 * in the BPFFS specified by a path. This decrements program's in-kernel
452 * reference count.
453 *
454 * The file pinning the BPF program can also be unlinked by a different
455 * process in which case this function will return an error.
456 *
457 * @param prog BPF program to unpin
458 * @param path file path to the pin in a BPF file system
459 * @return 0, on success; negative error code, otherwise
460 */
461LIBBPF_API int bpf_program__unpin(struct bpf_program *prog, const char *path);
462LIBBPF_API void bpf_program__unload(struct bpf_program *prog);
463
464struct bpf_link;
465
466LIBBPF_API struct bpf_link *bpf_link__open(const char *path);
467LIBBPF_API int bpf_link__fd(const struct bpf_link *link);
468LIBBPF_API const char *bpf_link__pin_path(const struct bpf_link *link);
469/**
470 * @brief **bpf_link__pin()** pins the BPF link to a file
471 * in the BPF FS specified by a path. This increments the links
472 * reference count, allowing it to stay loaded after the process
473 * which loaded it has exited.
474 *
475 * @param link BPF link to pin, must already be loaded
476 * @param path file path in a BPF file system
477 * @return 0, on success; negative error code, otherwise
478 */
479
480LIBBPF_API int bpf_link__pin(struct bpf_link *link, const char *path);
481
482/**
483 * @brief **bpf_link__unpin()** unpins the BPF link from a file
484 * in the BPFFS. This decrements link's in-kernel reference count.
485 *
486 * The file pinning the BPF link can also be unlinked by a different
487 * process in which case this function will return an error.
488 *
489 * @param link BPF link to unpin
490 * @return 0, on success; negative error code, otherwise
491 */
492LIBBPF_API int bpf_link__unpin(struct bpf_link *link);
493LIBBPF_API int bpf_link__update_program(struct bpf_link *link,
494 struct bpf_program *prog);
495LIBBPF_API void bpf_link__disconnect(struct bpf_link *link);
496LIBBPF_API int bpf_link__detach(struct bpf_link *link);
497LIBBPF_API int bpf_link__destroy(struct bpf_link *link);
498
499/**
500 * @brief **bpf_program__attach()** is a generic function for attaching
501 * a BPF program based on auto-detection of program type, attach type,
502 * and extra parameters, where applicable.
503 *
504 * @param prog BPF program to attach
505 * @return Reference to the newly created BPF link; or NULL is returned on error,
506 * error code is stored in errno
507 *
508 * This is supported for:
509 * - kprobe/kretprobe (depends on SEC() definition)
510 * - uprobe/uretprobe (depends on SEC() definition)
511 * - tracepoint
512 * - raw tracepoint
513 * - tracing programs (typed raw TP/fentry/fexit/fmod_ret)
514 */
515LIBBPF_API struct bpf_link *
516bpf_program__attach(const struct bpf_program *prog);
517
518struct bpf_perf_event_opts {
519 /* size of this struct, for forward/backward compatibility */
520 size_t sz;
521 /* custom user-provided value fetchable through bpf_get_attach_cookie() */
522 __u64 bpf_cookie;
523 /* don't use BPF link when attach BPF program */
524 bool force_ioctl_attach;
525 /* don't automatically enable the event */
526 bool dont_enable;
527 size_t :0;
528};
529#define bpf_perf_event_opts__last_field dont_enable
530
531LIBBPF_API struct bpf_link *
532bpf_program__attach_perf_event(const struct bpf_program *prog, int pfd);
533
534LIBBPF_API struct bpf_link *
535bpf_program__attach_perf_event_opts(const struct bpf_program *prog, int pfd,
536 const struct bpf_perf_event_opts *opts);
537
538/**
539 * enum probe_attach_mode - the mode to attach kprobe/uprobe
540 *
541 * force libbpf to attach kprobe/uprobe in specific mode, -ENOTSUP will
542 * be returned if it is not supported by the kernel.
543 */
544enum probe_attach_mode {
545 /* attach probe in latest supported mode by kernel */
546 PROBE_ATTACH_MODE_DEFAULT = 0,
547 /* attach probe in legacy mode, using debugfs/tracefs */
548 PROBE_ATTACH_MODE_LEGACY,
549 /* create perf event with perf_event_open() syscall */
550 PROBE_ATTACH_MODE_PERF,
551 /* attach probe with BPF link */
552 PROBE_ATTACH_MODE_LINK,
553};
554
555struct bpf_kprobe_opts {
556 /* size of this struct, for forward/backward compatibility */
557 size_t sz;
558 /* custom user-provided value fetchable through bpf_get_attach_cookie() */
559 __u64 bpf_cookie;
560 /* function offset, or raw address if func_name == NULL */
561 size_t offset;
562 /* kprobe is return probe */
563 bool retprobe;
564 /* kprobe attach mode */
565 enum probe_attach_mode attach_mode;
566 size_t :0;
567};
568
569#define bpf_kprobe_opts__last_field attach_mode
570
571/**
572 * @brief **bpf_program__attach_kprobe()** attaches a BPF program to a
573 * kernel function entry or return.
574 *
575 * @param prog BPF program to attach
576 * @param retprobe Attach to function return
577 * @param func_name Name of the kernel function to attach to
578 * @return Reference to the newly created BPF link; or NULL is returned on
579 * error, error code is stored in errno
580 */
581LIBBPF_API struct bpf_link *
582bpf_program__attach_kprobe(const struct bpf_program *prog, bool retprobe,
583 const char *func_name);
584
585/**
586 * @brief **bpf_program__attach_kprobe_opts()** is just like
587 * bpf_program__attach_kprobe() except with an options struct
588 * for various configurations.
589 *
590 * @param prog BPF program to attach
591 * @param func_name Name of the kernel function to attach to. If NULL,
592 * opts->offset is treated as a raw kernel address. Raw-address attach
593 * is supported with PROBE_ATTACH_MODE_PERF and PROBE_ATTACH_MODE_LINK.
594 * @param opts Options for altering program attachment
595 * @return Reference to the newly created BPF link; or NULL is returned on
596 * error, error code is stored in errno
597 */
598LIBBPF_API struct bpf_link *
599bpf_program__attach_kprobe_opts(const struct bpf_program *prog,
600 const char *func_name,
601 const struct bpf_kprobe_opts *opts);
602
603struct bpf_kprobe_multi_opts {
604 /* size of this struct, for forward/backward compatibility */
605 size_t sz;
606 /* array of function symbols to attach */
607 const char **syms;
608 /* array of function addresses to attach */
609 const unsigned long *addrs;
610 /* array of user-provided values fetchable through bpf_get_attach_cookie */
611 const __u64 *cookies;
612 /* number of elements in syms/addrs/cookies arrays */
613 size_t cnt;
614 /* create return kprobes */
615 bool retprobe;
616 /* create session kprobes */
617 bool session;
618 /* enforce unique match */
619 bool unique_match;
620 size_t :0;
621};
622
623#define bpf_kprobe_multi_opts__last_field unique_match
624
625LIBBPF_API struct bpf_link *
626bpf_program__attach_kprobe_multi_opts(const struct bpf_program *prog,
627 const char *pattern,
628 const struct bpf_kprobe_multi_opts *opts);
629
630struct bpf_uprobe_multi_opts {
631 /* size of this struct, for forward/backward compatibility */
632 size_t sz;
633 /* array of function symbols to attach to */
634 const char **syms;
635 /* array of function addresses to attach to */
636 const unsigned long *offsets;
637 /* optional, array of associated ref counter offsets */
638 const unsigned long *ref_ctr_offsets;
639 /* optional, array of associated BPF cookies */
640 const __u64 *cookies;
641 /* number of elements in syms/addrs/cookies arrays */
642 size_t cnt;
643 /* create return uprobes */
644 bool retprobe;
645 /* create session kprobes */
646 bool session;
647 size_t :0;
648};
649
650#define bpf_uprobe_multi_opts__last_field session
651
652/**
653 * @brief **bpf_program__attach_uprobe_multi()** attaches a BPF program
654 * to multiple uprobes with uprobe_multi link.
655 *
656 * User can specify 2 mutually exclusive set of inputs:
657 *
658 * 1) use only path/func_pattern/pid arguments
659 *
660 * 2) use path/pid with allowed combinations of
661 * syms/offsets/ref_ctr_offsets/cookies/cnt
662 *
663 * - syms and offsets are mutually exclusive
664 * - ref_ctr_offsets and cookies are optional
665 *
666 *
667 * @param prog BPF program to attach
668 * @param pid Process ID to attach the uprobe to, 0 for self (own process),
669 * -1 for all processes
670 * @param binary_path Path to binary
671 * @param func_pattern Regular expression to specify functions to attach
672 * BPF program to
673 * @param opts Additional options (see **struct bpf_uprobe_multi_opts**)
674 * @return 0, on success; negative error code, otherwise
675 */
676LIBBPF_API struct bpf_link *
677bpf_program__attach_uprobe_multi(const struct bpf_program *prog,
678 pid_t pid,
679 const char *binary_path,
680 const char *func_pattern,
681 const struct bpf_uprobe_multi_opts *opts);
682
683struct bpf_ksyscall_opts {
684 /* size of this struct, for forward/backward compatibility */
685 size_t sz;
686 /* custom user-provided value fetchable through bpf_get_attach_cookie() */
687 __u64 bpf_cookie;
688 /* attach as return probe? */
689 bool retprobe;
690 size_t :0;
691};
692#define bpf_ksyscall_opts__last_field retprobe
693
694/**
695 * @brief **bpf_program__attach_ksyscall()** attaches a BPF program
696 * to kernel syscall handler of a specified syscall. Optionally it's possible
697 * to request to install retprobe that will be triggered at syscall exit. It's
698 * also possible to associate BPF cookie (though options).
699 *
700 * Libbpf automatically will determine correct full kernel function name,
701 * which depending on system architecture and kernel version/configuration
702 * could be of the form __<arch>_sys_<syscall> or __se_sys_<syscall>, and will
703 * attach specified program using kprobe/kretprobe mechanism.
704 *
705 * **bpf_program__attach_ksyscall()** is an API counterpart of declarative
706 * **SEC("ksyscall/<syscall>")** annotation of BPF programs.
707 *
708 * At the moment **SEC("ksyscall")** and **bpf_program__attach_ksyscall()** do
709 * not handle all the calling convention quirks for mmap(), clone() and compat
710 * syscalls. It also only attaches to "native" syscall interfaces. If host
711 * system supports compat syscalls or defines 32-bit syscalls in 64-bit
712 * kernel, such syscall interfaces won't be attached to by libbpf.
713 *
714 * These limitations may or may not change in the future. Therefore it is
715 * recommended to use SEC("kprobe") for these syscalls or if working with
716 * compat and 32-bit interfaces is required.
717 *
718 * @param prog BPF program to attach
719 * @param syscall_name Symbolic name of the syscall (e.g., "bpf")
720 * @param opts Additional options (see **struct bpf_ksyscall_opts**)
721 * @return Reference to the newly created BPF link; or NULL is returned on
722 * error, error code is stored in errno
723 */
724LIBBPF_API struct bpf_link *
725bpf_program__attach_ksyscall(const struct bpf_program *prog,
726 const char *syscall_name,
727 const struct bpf_ksyscall_opts *opts);
728
729struct bpf_uprobe_opts {
730 /* size of this struct, for forward/backward compatibility */
731 size_t sz;
732 /* offset of kernel reference counted USDT semaphore, added in
733 * a6ca88b241d5 ("trace_uprobe: support reference counter in fd-based uprobe")
734 */
735 size_t ref_ctr_offset;
736 /* custom user-provided value fetchable through bpf_get_attach_cookie() */
737 __u64 bpf_cookie;
738 /* uprobe is return probe, invoked at function return time */
739 bool retprobe;
740 /* Function name to attach to. Could be an unqualified ("abc") or library-qualified
741 * "abc@LIBXYZ" name. To specify function entry, func_name should be set while
742 * func_offset argument to bpf_prog__attach_uprobe_opts() should be 0. To trace an
743 * offset within a function, specify func_name and use func_offset argument to specify
744 * offset within the function. Shared library functions must specify the shared library
745 * binary_path.
746 */
747 const char *func_name;
748 /* uprobe attach mode */
749 enum probe_attach_mode attach_mode;
750 size_t :0;
751};
752#define bpf_uprobe_opts__last_field attach_mode
753
754/**
755 * @brief **bpf_program__attach_uprobe()** attaches a BPF program
756 * to the userspace function which is found by binary path and
757 * offset. You can optionally specify a particular process to attach
758 * to. You can also optionally attach the program to the function
759 * exit instead of entry.
760 *
761 * @param prog BPF program to attach
762 * @param retprobe Attach to function exit
763 * @param pid Process ID to attach the uprobe to, 0 for self (own process),
764 * -1 for all processes
765 * @param binary_path Path to binary that contains the function symbol
766 * @param func_offset Offset within the binary of the function symbol
767 * @return Reference to the newly created BPF link; or NULL is returned on error,
768 * error code is stored in errno
769 */
770LIBBPF_API struct bpf_link *
771bpf_program__attach_uprobe(const struct bpf_program *prog, bool retprobe,
772 pid_t pid, const char *binary_path,
773 size_t func_offset);
774
775/**
776 * @brief **bpf_program__attach_uprobe_opts()** is just like
777 * bpf_program__attach_uprobe() except with a options struct
778 * for various configurations.
779 *
780 * @param prog BPF program to attach
781 * @param pid Process ID to attach the uprobe to, 0 for self (own process),
782 * -1 for all processes
783 * @param binary_path Path to binary that contains the function symbol
784 * @param func_offset Offset within the binary of the function symbol
785 * @param opts Options for altering program attachment
786 * @return Reference to the newly created BPF link; or NULL is returned on error,
787 * error code is stored in errno
788 */
789LIBBPF_API struct bpf_link *
790bpf_program__attach_uprobe_opts(const struct bpf_program *prog, pid_t pid,
791 const char *binary_path, size_t func_offset,
792 const struct bpf_uprobe_opts *opts);
793
794struct bpf_usdt_opts {
795 /* size of this struct, for forward/backward compatibility */
796 size_t sz;
797 /* custom user-provided value accessible through usdt_cookie() */
798 __u64 usdt_cookie;
799 size_t :0;
800};
801#define bpf_usdt_opts__last_field usdt_cookie
802
803/**
804 * @brief **bpf_program__attach_usdt()** is just like
805 * bpf_program__attach_uprobe_opts() except it covers USDT (User-space
806 * Statically Defined Tracepoint) attachment, instead of attaching to
807 * user-space function entry or exit.
808 *
809 * @param prog BPF program to attach
810 * @param pid Process ID to attach the uprobe to, 0 for self (own process),
811 * -1 for all processes
812 * @param binary_path Path to binary that contains provided USDT probe
813 * @param usdt_provider USDT provider name
814 * @param usdt_name USDT probe name
815 * @param opts Options for altering program attachment
816 * @return Reference to the newly created BPF link; or NULL is returned on error,
817 * error code is stored in errno
818 */
819LIBBPF_API struct bpf_link *
820bpf_program__attach_usdt(const struct bpf_program *prog,
821 pid_t pid, const char *binary_path,
822 const char *usdt_provider, const char *usdt_name,
823 const struct bpf_usdt_opts *opts);
824
825struct bpf_tracepoint_opts {
826 /* size of this struct, for forward/backward compatibility */
827 size_t sz;
828 /* custom user-provided value fetchable through bpf_get_attach_cookie() */
829 __u64 bpf_cookie;
830};
831#define bpf_tracepoint_opts__last_field bpf_cookie
832
833LIBBPF_API struct bpf_link *
834bpf_program__attach_tracepoint(const struct bpf_program *prog,
835 const char *tp_category,
836 const char *tp_name);
837LIBBPF_API struct bpf_link *
838bpf_program__attach_tracepoint_opts(const struct bpf_program *prog,
839 const char *tp_category,
840 const char *tp_name,
841 const struct bpf_tracepoint_opts *opts);
842
843struct bpf_raw_tracepoint_opts {
844 size_t sz; /* size of this struct for forward/backward compatibility */
845 __u64 cookie;
846 size_t :0;
847};
848#define bpf_raw_tracepoint_opts__last_field cookie
849
850LIBBPF_API struct bpf_link *
851bpf_program__attach_raw_tracepoint(const struct bpf_program *prog,
852 const char *tp_name);
853LIBBPF_API struct bpf_link *
854bpf_program__attach_raw_tracepoint_opts(const struct bpf_program *prog,
855 const char *tp_name,
856 struct bpf_raw_tracepoint_opts *opts);
857
858struct bpf_trace_opts {
859 /* size of this struct, for forward/backward compatibility */
860 size_t sz;
861 /* custom user-provided value fetchable through bpf_get_attach_cookie() */
862 __u64 cookie;
863};
864#define bpf_trace_opts__last_field cookie
865
866LIBBPF_API struct bpf_link *
867bpf_program__attach_trace(const struct bpf_program *prog);
868LIBBPF_API struct bpf_link *
869bpf_program__attach_trace_opts(const struct bpf_program *prog, const struct bpf_trace_opts *opts);
870
871LIBBPF_API struct bpf_link *
872bpf_program__attach_lsm(const struct bpf_program *prog);
873LIBBPF_API struct bpf_link *
874bpf_program__attach_cgroup(const struct bpf_program *prog, int cgroup_fd);
875LIBBPF_API struct bpf_link *
876bpf_program__attach_netns(const struct bpf_program *prog, int netns_fd);
877LIBBPF_API struct bpf_link *
878bpf_program__attach_sockmap(const struct bpf_program *prog, int map_fd);
879LIBBPF_API struct bpf_link *
880bpf_program__attach_xdp(const struct bpf_program *prog, int ifindex);
881LIBBPF_API struct bpf_link *
882bpf_program__attach_freplace(const struct bpf_program *prog,
883 int target_fd, const char *attach_func_name);
884
885struct bpf_netfilter_opts {
886 /* size of this struct, for forward/backward compatibility */
887 size_t sz;
888
889 __u32 pf;
890 __u32 hooknum;
891 __s32 priority;
892 __u32 flags;
893};
894#define bpf_netfilter_opts__last_field flags
895
896LIBBPF_API struct bpf_link *
897bpf_program__attach_netfilter(const struct bpf_program *prog,
898 const struct bpf_netfilter_opts *opts);
899
900struct bpf_tcx_opts {
901 /* size of this struct, for forward/backward compatibility */
902 size_t sz;
903 __u32 flags;
904 __u32 relative_fd;
905 __u32 relative_id;
906 __u64 expected_revision;
907 size_t :0;
908};
909#define bpf_tcx_opts__last_field expected_revision
910
911LIBBPF_API struct bpf_link *
912bpf_program__attach_tcx(const struct bpf_program *prog, int ifindex,
913 const struct bpf_tcx_opts *opts);
914
915struct bpf_netkit_opts {
916 /* size of this struct, for forward/backward compatibility */
917 size_t sz;
918 __u32 flags;
919 __u32 relative_fd;
920 __u32 relative_id;
921 __u64 expected_revision;
922 size_t :0;
923};
924#define bpf_netkit_opts__last_field expected_revision
925
926LIBBPF_API struct bpf_link *
927bpf_program__attach_netkit(const struct bpf_program *prog, int ifindex,
928 const struct bpf_netkit_opts *opts);
929
930struct bpf_cgroup_opts {
931 /* size of this struct, for forward/backward compatibility */
932 size_t sz;
933 __u32 flags;
934 __u32 relative_fd;
935 __u32 relative_id;
936 __u64 expected_revision;
937 size_t :0;
938};
939#define bpf_cgroup_opts__last_field expected_revision
940
941LIBBPF_API struct bpf_link *
942bpf_program__attach_cgroup_opts(const struct bpf_program *prog, int cgroup_fd,
943 const struct bpf_cgroup_opts *opts);
944
945struct bpf_map;
946
947LIBBPF_API struct bpf_link *bpf_map__attach_struct_ops(const struct bpf_map *map);
948LIBBPF_API int bpf_link__update_map(struct bpf_link *link, const struct bpf_map *map);
949
950struct bpf_iter_attach_opts {
951 size_t sz; /* size of this struct for forward/backward compatibility */
952 union bpf_iter_link_info *link_info;
953 __u32 link_info_len;
954};
955#define bpf_iter_attach_opts__last_field link_info_len
956
957LIBBPF_API struct bpf_link *
958bpf_program__attach_iter(const struct bpf_program *prog,
959 const struct bpf_iter_attach_opts *opts);
960
961LIBBPF_API enum bpf_prog_type bpf_program__type(const struct bpf_program *prog);
962
963/**
964 * @brief **bpf_program__set_type()** sets the program
965 * type of the passed BPF program.
966 * @param prog BPF program to set the program type for
967 * @param type program type to set the BPF map to have
968 * @return error code; or 0 if no error. An error occurs
969 * if the object is already loaded.
970 *
971 * This must be called before the BPF object is loaded,
972 * otherwise it has no effect and an error is returned.
973 */
974LIBBPF_API int bpf_program__set_type(struct bpf_program *prog,
975 enum bpf_prog_type type);
976
977LIBBPF_API enum bpf_attach_type
978bpf_program__expected_attach_type(const struct bpf_program *prog);
979
980/**
981 * @brief **bpf_program__set_expected_attach_type()** sets the
982 * attach type of the passed BPF program. This is used for
983 * auto-detection of attachment when programs are loaded.
984 * @param prog BPF program to set the attach type for
985 * @param type attach type to set the BPF map to have
986 * @return error code; or 0 if no error. An error occurs
987 * if the object is already loaded.
988 *
989 * This must be called before the BPF object is loaded,
990 * otherwise it has no effect and an error is returned.
991 */
992LIBBPF_API int
993bpf_program__set_expected_attach_type(struct bpf_program *prog,
994 enum bpf_attach_type type);
995
996LIBBPF_API __u32 bpf_program__flags(const struct bpf_program *prog);
997LIBBPF_API int bpf_program__set_flags(struct bpf_program *prog, __u32 flags);
998
999/* Per-program log level and log buffer getters/setters.
1000 * See bpf_object_open_opts comments regarding log_level and log_buf
1001 * interactions.
1002 */
1003LIBBPF_API __u32 bpf_program__log_level(const struct bpf_program *prog);
1004LIBBPF_API int bpf_program__set_log_level(struct bpf_program *prog, __u32 log_level);
1005LIBBPF_API const char *bpf_program__log_buf(const struct bpf_program *prog, size_t *log_size);
1006LIBBPF_API int bpf_program__set_log_buf(struct bpf_program *prog, char *log_buf, size_t log_size);
1007
1008LIBBPF_API struct bpf_func_info *bpf_program__func_info(const struct bpf_program *prog);
1009LIBBPF_API __u32 bpf_program__func_info_cnt(const struct bpf_program *prog);
1010
1011LIBBPF_API struct bpf_line_info *bpf_program__line_info(const struct bpf_program *prog);
1012LIBBPF_API __u32 bpf_program__line_info_cnt(const struct bpf_program *prog);
1013
1014/**
1015 * @brief **bpf_program__set_attach_target()** sets BTF-based attach target
1016 * for supported BPF program types:
1017 * - BTF-aware raw tracepoints (tp_btf);
1018 * - fentry/fexit/fmod_ret;
1019 * - lsm;
1020 * - freplace.
1021 * @param prog BPF program to configure; must be not yet loaded.
1022 * @param attach_prog_fd FD of target BPF program (for freplace/extension).
1023 * If >0 and func name omitted, defers BTF ID resolution.
1024 * @param attach_func_name Target function name. Used either with
1025 * attach_prog_fd to find destination BTF type ID in that BPF program, or
1026 * alone (no attach_prog_fd) to resolve kernel (vmlinux/module) BTF ID.
1027 * Must be provided if attach_prog_fd is 0.
1028 * @return error code; or 0 if no error occurred.
1029 */
1030LIBBPF_API int
1031bpf_program__set_attach_target(struct bpf_program *prog, int attach_prog_fd,
1032 const char *attach_func_name);
1033
1034struct bpf_prog_assoc_struct_ops_opts; /* defined in bpf.h */
1035
1036/**
1037 * @brief **bpf_program__assoc_struct_ops()** associates a BPF program with a
1038 * struct_ops map.
1039 *
1040 * @param prog BPF program
1041 * @param map struct_ops map to be associated with the BPF program
1042 * @param opts optional options, can be NULL
1043 *
1044 * @return 0, on success; negative error code, otherwise
1045 */
1046LIBBPF_API int
1047bpf_program__assoc_struct_ops(struct bpf_program *prog, struct bpf_map *map,
1048 struct bpf_prog_assoc_struct_ops_opts *opts);
1049
1050/**
1051 * @brief **bpf_object__find_map_by_name()** returns BPF map of
1052 * the given name, if it exists within the passed BPF object
1053 * @param obj BPF object
1054 * @param name name of the BPF map
1055 * @return BPF map instance, if such map exists within the BPF object;
1056 * or NULL otherwise.
1057 */
1058LIBBPF_API struct bpf_map *
1059bpf_object__find_map_by_name(const struct bpf_object *obj, const char *name);
1060
1061LIBBPF_API int
1062bpf_object__find_map_fd_by_name(const struct bpf_object *obj, const char *name);
1063
1064LIBBPF_API struct bpf_map *
1065bpf_object__next_map(const struct bpf_object *obj, const struct bpf_map *map);
1066
1067#define bpf_object__for_each_map(pos, obj) \
1068 for ((pos) = bpf_object__next_map((obj), NULL); \
1069 (pos) != NULL; \
1070 (pos) = bpf_object__next_map((obj), (pos)))
1071#define bpf_map__for_each bpf_object__for_each_map
1072
1073LIBBPF_API struct bpf_map *
1074bpf_object__prev_map(const struct bpf_object *obj, const struct bpf_map *map);
1075
1076/**
1077 * @brief **bpf_map__set_autocreate()** sets whether libbpf has to auto-create
1078 * BPF map during BPF object load phase.
1079 * @param map the BPF map instance
1080 * @param autocreate whether to create BPF map during BPF object load
1081 * @return 0 on success; -EBUSY if BPF object was already loaded
1082 *
1083 * **bpf_map__set_autocreate()** allows to opt-out from libbpf auto-creating
1084 * BPF map. By default, libbpf will attempt to create every single BPF map
1085 * defined in BPF object file using BPF_MAP_CREATE command of bpf() syscall
1086 * and fill in map FD in BPF instructions.
1087 *
1088 * This API allows to opt-out of this process for specific map instance. This
1089 * can be useful if host kernel doesn't support such BPF map type or used
1090 * combination of flags and user application wants to avoid creating such
1091 * a map in the first place. User is still responsible to make sure that their
1092 * BPF-side code that expects to use such missing BPF map is recognized by BPF
1093 * verifier as dead code, otherwise BPF verifier will reject such BPF program.
1094 */
1095LIBBPF_API int bpf_map__set_autocreate(struct bpf_map *map, bool autocreate);
1096LIBBPF_API bool bpf_map__autocreate(const struct bpf_map *map);
1097
1098/**
1099 * @brief **bpf_map__set_autoattach()** sets whether libbpf has to auto-attach
1100 * map during BPF skeleton attach phase.
1101 * @param map the BPF map instance
1102 * @param autoattach whether to attach map during BPF skeleton attach phase
1103 * @return 0 on success; negative error code, otherwise
1104 */
1105LIBBPF_API int bpf_map__set_autoattach(struct bpf_map *map, bool autoattach);
1106
1107/**
1108 * @brief **bpf_map__autoattach()** returns whether BPF map is configured to
1109 * auto-attach during BPF skeleton attach phase.
1110 * @param map the BPF map instance
1111 * @return true if map is set to auto-attach during skeleton attach phase; false, otherwise
1112 */
1113LIBBPF_API bool bpf_map__autoattach(const struct bpf_map *map);
1114
1115/**
1116 * @brief **bpf_map__fd()** gets the file descriptor of the passed
1117 * BPF map
1118 * @param map the BPF map instance
1119 * @return the file descriptor; or -EINVAL in case of an error
1120 */
1121LIBBPF_API int bpf_map__fd(const struct bpf_map *map);
1122LIBBPF_API int bpf_map__reuse_fd(struct bpf_map *map, int fd);
1123/* get map name */
1124LIBBPF_API const char *bpf_map__name(const struct bpf_map *map);
1125/* get/set map type */
1126LIBBPF_API enum bpf_map_type bpf_map__type(const struct bpf_map *map);
1127LIBBPF_API int bpf_map__set_type(struct bpf_map *map, enum bpf_map_type type);
1128/* get/set map size (max_entries) */
1129LIBBPF_API __u32 bpf_map__max_entries(const struct bpf_map *map);
1130LIBBPF_API int bpf_map__set_max_entries(struct bpf_map *map, __u32 max_entries);
1131/* get/set map flags */
1132LIBBPF_API __u32 bpf_map__map_flags(const struct bpf_map *map);
1133LIBBPF_API int bpf_map__set_map_flags(struct bpf_map *map, __u32 flags);
1134/* get/set map NUMA node */
1135LIBBPF_API __u32 bpf_map__numa_node(const struct bpf_map *map);
1136LIBBPF_API int bpf_map__set_numa_node(struct bpf_map *map, __u32 numa_node);
1137/* get/set map key size */
1138LIBBPF_API __u32 bpf_map__key_size(const struct bpf_map *map);
1139LIBBPF_API int bpf_map__set_key_size(struct bpf_map *map, __u32 size);
1140/* get map value size */
1141LIBBPF_API __u32 bpf_map__value_size(const struct bpf_map *map);
1142/**
1143 * @brief **bpf_map__set_value_size()** sets map value size.
1144 * @param map the BPF map instance
1145 * @param size the new value size
1146 * @return 0, on success; negative error, otherwise
1147 *
1148 * There is a special case for maps with associated memory-mapped regions, like
1149 * the global data section maps (bss, data, rodata). When this function is used
1150 * on such a map, the mapped region is resized. Afterward, an attempt is made to
1151 * adjust the corresponding BTF info. This attempt is best-effort and can only
1152 * succeed if the last variable of the data section map is an array. The array
1153 * BTF type is replaced by a new BTF array type with a different length.
1154 * Any previously existing pointers returned from bpf_map__initial_value() or
1155 * corresponding data section skeleton pointer must be reinitialized.
1156 */
1157LIBBPF_API int bpf_map__set_value_size(struct bpf_map *map, __u32 size);
1158/* get map key/value BTF type IDs */
1159LIBBPF_API __u32 bpf_map__btf_key_type_id(const struct bpf_map *map);
1160LIBBPF_API __u32 bpf_map__btf_value_type_id(const struct bpf_map *map);
1161/* get/set map if_index */
1162LIBBPF_API __u32 bpf_map__ifindex(const struct bpf_map *map);
1163LIBBPF_API int bpf_map__set_ifindex(struct bpf_map *map, __u32 ifindex);
1164/* get/set map map_extra flags */
1165LIBBPF_API __u64 bpf_map__map_extra(const struct bpf_map *map);
1166LIBBPF_API int bpf_map__set_map_extra(struct bpf_map *map, __u64 map_extra);
1167
1168LIBBPF_API int bpf_map__set_initial_value(struct bpf_map *map,
1169 const void *data, size_t size);
1170LIBBPF_API void *bpf_map__initial_value(const struct bpf_map *map, size_t *psize);
1171
1172/**
1173 * @brief **bpf_map__is_internal()** tells the caller whether or not the
1174 * passed map is a special map created by libbpf automatically for things like
1175 * global variables, __ksym externs, Kconfig values, etc
1176 * @param map the bpf_map
1177 * @return true, if the map is an internal map; false, otherwise
1178 */
1179LIBBPF_API bool bpf_map__is_internal(const struct bpf_map *map);
1180
1181/**
1182 * @brief **bpf_map__set_pin_path()** sets the path attribute that tells where the
1183 * BPF map should be pinned. This does not actually create the 'pin'.
1184 * @param map The bpf_map
1185 * @param path The path
1186 * @return 0, on success; negative error, otherwise
1187 */
1188LIBBPF_API int bpf_map__set_pin_path(struct bpf_map *map, const char *path);
1189
1190/**
1191 * @brief **bpf_map__pin_path()** gets the path attribute that tells where the
1192 * BPF map should be pinned.
1193 * @param map The bpf_map
1194 * @return The path string; which can be NULL
1195 */
1196LIBBPF_API const char *bpf_map__pin_path(const struct bpf_map *map);
1197
1198/**
1199 * @brief **bpf_map__is_pinned()** tells the caller whether or not the
1200 * passed map has been pinned via a 'pin' file.
1201 * @param map The bpf_map
1202 * @return true, if the map is pinned; false, otherwise
1203 */
1204LIBBPF_API bool bpf_map__is_pinned(const struct bpf_map *map);
1205
1206/**
1207 * @brief **bpf_map__pin()** creates a file that serves as a 'pin'
1208 * for the BPF map. This increments the reference count on the
1209 * BPF map which will keep the BPF map loaded even after the
1210 * userspace process which loaded it has exited.
1211 * @param map The bpf_map to pin
1212 * @param path A file path for the 'pin'
1213 * @return 0, on success; negative error, otherwise
1214 *
1215 * If `path` is NULL the maps `pin_path` attribute will be used. If this is
1216 * also NULL, an error will be returned and the map will not be pinned.
1217 */
1218LIBBPF_API int bpf_map__pin(struct bpf_map *map, const char *path);
1219
1220/**
1221 * @brief **bpf_map__unpin()** removes the file that serves as a
1222 * 'pin' for the BPF map.
1223 * @param map The bpf_map to unpin
1224 * @param path A file path for the 'pin'
1225 * @return 0, on success; negative error, otherwise
1226 *
1227 * The `path` parameter can be NULL, in which case the `pin_path`
1228 * map attribute is unpinned. If both the `path` parameter and
1229 * `pin_path` map attribute are set, they must be equal.
1230 */
1231LIBBPF_API int bpf_map__unpin(struct bpf_map *map, const char *path);
1232
1233LIBBPF_API int bpf_map__set_inner_map_fd(struct bpf_map *map, int fd);
1234LIBBPF_API struct bpf_map *bpf_map__inner_map(struct bpf_map *map);
1235
1236/**
1237 * @brief **bpf_map__lookup_elem()** allows to lookup BPF map value
1238 * corresponding to provided key.
1239 * @param map BPF map to lookup element in
1240 * @param key pointer to memory containing bytes of the key used for lookup
1241 * @param key_sz size in bytes of key data, needs to match BPF map definition's **key_size**
1242 * @param value pointer to memory in which looked up value will be stored
1243 * @param value_sz size in byte of value data memory; it has to match BPF map
1244 * definition's **value_size**. For per-CPU BPF maps, value size can be
1245 * `value_size` if either **BPF_F_CPU** or **BPF_F_ALL_CPUS** is specified
1246 * in **flags**, otherwise a product of BPF map value size and number of
1247 * possible CPUs in the system (could be fetched with
1248 * **libbpf_num_possible_cpus()**). Note also that for per-CPU values value
1249 * size has to be aligned up to closest 8 bytes, so expected size is:
1250 * `round_up(value_size, 8) * libbpf_num_possible_cpus()`.
1251 * @param flags extra flags passed to kernel for this operation
1252 * @return 0, on success; negative error, otherwise
1253 *
1254 * **bpf_map__lookup_elem()** is high-level equivalent of
1255 * **bpf_map_lookup_elem()** API with added check for key and value size.
1256 */
1257LIBBPF_API int bpf_map__lookup_elem(const struct bpf_map *map,
1258 const void *key, size_t key_sz,
1259 void *value, size_t value_sz, __u64 flags);
1260
1261/**
1262 * @brief **bpf_map__update_elem()** allows to insert or update value in BPF
1263 * map that corresponds to provided key.
1264 * @param map BPF map to insert to or update element in
1265 * @param key pointer to memory containing bytes of the key
1266 * @param key_sz size in bytes of key data, needs to match BPF map definition's **key_size**
1267 * @param value pointer to memory containing bytes of the value
1268 * @param value_sz refer to **bpf_map__lookup_elem**'s description.'
1269 * @param flags extra flags passed to kernel for this operation
1270 * @return 0, on success; negative error, otherwise
1271 *
1272 * **bpf_map__update_elem()** is high-level equivalent of
1273 * **bpf_map_update_elem()** API with added check for key and value size.
1274 */
1275LIBBPF_API int bpf_map__update_elem(const struct bpf_map *map,
1276 const void *key, size_t key_sz,
1277 const void *value, size_t value_sz, __u64 flags);
1278
1279/**
1280 * @brief **bpf_map__delete_elem()** allows to delete element in BPF map that
1281 * corresponds to provided key.
1282 * @param map BPF map to delete element from
1283 * @param key pointer to memory containing bytes of the key
1284 * @param key_sz size in bytes of key data, needs to match BPF map definition's **key_size**
1285 * @param flags extra flags passed to kernel for this operation
1286 * @return 0, on success; negative error, otherwise
1287 *
1288 * **bpf_map__delete_elem()** is high-level equivalent of
1289 * **bpf_map_delete_elem()** API with added check for key size.
1290 */
1291LIBBPF_API int bpf_map__delete_elem(const struct bpf_map *map,
1292 const void *key, size_t key_sz, __u64 flags);
1293
1294/**
1295 * @brief **bpf_map__lookup_and_delete_elem()** allows to lookup BPF map value
1296 * corresponding to provided key and atomically delete it afterwards.
1297 * @param map BPF map to lookup element in
1298 * @param key pointer to memory containing bytes of the key used for lookup
1299 * @param key_sz size in bytes of key data, needs to match BPF map definition's **key_size**
1300 * @param value pointer to memory in which looked up value will be stored
1301 * @param value_sz size in byte of value data memory; it has to match BPF map
1302 * definition's **value_size**. For per-CPU BPF maps value size has to be
1303 * a product of BPF map value size and number of possible CPUs in the system
1304 * (could be fetched with **libbpf_num_possible_cpus()**). Note also that for
1305 * per-CPU values value size has to be aligned up to closest 8 bytes for
1306 * alignment reasons, so expected size is: `round_up(value_size, 8)
1307 * * libbpf_num_possible_cpus()`.
1308 * @param flags extra flags passed to kernel for this operation
1309 * @return 0, on success; negative error, otherwise
1310 *
1311 * **bpf_map__lookup_and_delete_elem()** is high-level equivalent of
1312 * **bpf_map_lookup_and_delete_elem()** API with added check for key and value size.
1313 */
1314LIBBPF_API int bpf_map__lookup_and_delete_elem(const struct bpf_map *map,
1315 const void *key, size_t key_sz,
1316 void *value, size_t value_sz, __u64 flags);
1317
1318/**
1319 * @brief **bpf_map__get_next_key()** allows to iterate BPF map keys by
1320 * fetching next key that follows current key.
1321 * @param map BPF map to fetch next key from
1322 * @param cur_key pointer to memory containing bytes of current key or NULL to
1323 * fetch the first key
1324 * @param next_key pointer to memory to write next key into
1325 * @param key_sz size in bytes of key data, needs to match BPF map definition's **key_size**
1326 * @return 0, on success; -ENOENT if **cur_key** is the last key in BPF map;
1327 * negative error, otherwise
1328 *
1329 * **bpf_map__get_next_key()** is high-level equivalent of
1330 * **bpf_map_get_next_key()** API with added check for key size.
1331 */
1332LIBBPF_API int bpf_map__get_next_key(const struct bpf_map *map,
1333 const void *cur_key, void *next_key, size_t key_sz);
1334/**
1335 * @brief **bpf_map__set_exclusive_program()** sets a map to be exclusive to the
1336 * specified program. This must be called *before* the map is created.
1337 *
1338 * @param map BPF map to make exclusive.
1339 * @param prog BPF program to be the exclusive user of the map. Must belong
1340 * to the same bpf_object as the map.
1341 * @return 0 on success; a negative error code otherwise.
1342 *
1343 * This function must be called after the BPF object is opened but before
1344 * it is loaded. Once the object is loaded, only the specified program
1345 * will be able to access the map's contents.
1346 */
1347LIBBPF_API int bpf_map__set_exclusive_program(struct bpf_map *map, struct bpf_program *prog);
1348
1349/**
1350 * @brief **bpf_map__exclusive_program()** returns the exclusive program
1351 * that is registered with the map (if any).
1352 * @param map BPF map to which the exclusive program is registered.
1353 * @return the registered exclusive program.
1354 */
1355LIBBPF_API struct bpf_program *bpf_map__exclusive_program(struct bpf_map *map);
1356
1357struct bpf_xdp_set_link_opts {
1358 size_t sz;
1359 int old_fd;
1360 size_t :0;
1361};
1362#define bpf_xdp_set_link_opts__last_field old_fd
1363
1364struct bpf_xdp_attach_opts {
1365 size_t sz;
1366 int old_prog_fd;
1367 size_t :0;
1368};
1369#define bpf_xdp_attach_opts__last_field old_prog_fd
1370
1371struct bpf_xdp_query_opts {
1372 size_t sz;
1373 __u32 prog_id; /* output */
1374 __u32 drv_prog_id; /* output */
1375 __u32 hw_prog_id; /* output */
1376 __u32 skb_prog_id; /* output */
1377 __u8 attach_mode; /* output */
1378 __u64 feature_flags; /* output */
1379 __u32 xdp_zc_max_segs; /* output */
1380 size_t :0;
1381};
1382#define bpf_xdp_query_opts__last_field xdp_zc_max_segs
1383
1384LIBBPF_API int bpf_xdp_attach(int ifindex, int prog_fd, __u32 flags,
1385 const struct bpf_xdp_attach_opts *opts);
1386LIBBPF_API int bpf_xdp_detach(int ifindex, __u32 flags,
1387 const struct bpf_xdp_attach_opts *opts);
1388LIBBPF_API int bpf_xdp_query(int ifindex, int flags, struct bpf_xdp_query_opts *opts);
1389LIBBPF_API int bpf_xdp_query_id(int ifindex, int flags, __u32 *prog_id);
1390
1391/* TC related API */
1392enum bpf_tc_attach_point {
1393 BPF_TC_INGRESS = 1 << 0,
1394 BPF_TC_EGRESS = 1 << 1,
1395 BPF_TC_CUSTOM = 1 << 2,
1396 BPF_TC_QDISC = 1 << 3,
1397};
1398
1399#define BPF_TC_PARENT(a, b) \
1400 ((((a) << 16) & 0xFFFF0000U) | ((b) & 0x0000FFFFU))
1401
1402enum bpf_tc_flags {
1403 BPF_TC_F_REPLACE = 1 << 0,
1404};
1405
1406struct bpf_tc_hook {
1407 size_t sz;
1408 int ifindex;
1409 enum bpf_tc_attach_point attach_point;
1410 __u32 parent;
1411 __u32 handle;
1412 const char *qdisc;
1413 size_t :0;
1414};
1415#define bpf_tc_hook__last_field qdisc
1416
1417struct bpf_tc_opts {
1418 size_t sz;
1419 int prog_fd;
1420 __u32 flags;
1421 __u32 prog_id;
1422 __u32 handle;
1423 __u32 priority;
1424 size_t :0;
1425};
1426#define bpf_tc_opts__last_field priority
1427
1428LIBBPF_API int bpf_tc_hook_create(struct bpf_tc_hook *hook);
1429LIBBPF_API int bpf_tc_hook_destroy(struct bpf_tc_hook *hook);
1430LIBBPF_API int bpf_tc_attach(const struct bpf_tc_hook *hook,
1431 struct bpf_tc_opts *opts);
1432LIBBPF_API int bpf_tc_detach(const struct bpf_tc_hook *hook,
1433 const struct bpf_tc_opts *opts);
1434LIBBPF_API int bpf_tc_query(const struct bpf_tc_hook *hook,
1435 struct bpf_tc_opts *opts);
1436
1437/* Ring buffer APIs */
1438struct ring_buffer;
1439struct ring;
1440struct user_ring_buffer;
1441
1442typedef int (*ring_buffer_sample_fn)(void *ctx, void *data, size_t size);
1443
1444struct ring_buffer_opts {
1445 size_t sz; /* size of this struct, for forward/backward compatibility */
1446};
1447
1448#define ring_buffer_opts__last_field sz
1449
1450LIBBPF_API struct ring_buffer *
1451ring_buffer__new(int map_fd, ring_buffer_sample_fn sample_cb, void *ctx,
1452 const struct ring_buffer_opts *opts);
1453LIBBPF_API void ring_buffer__free(struct ring_buffer *rb);
1454LIBBPF_API int ring_buffer__add(struct ring_buffer *rb, int map_fd,
1455 ring_buffer_sample_fn sample_cb, void *ctx);
1456LIBBPF_API int ring_buffer__poll(struct ring_buffer *rb, int timeout_ms);
1457LIBBPF_API int ring_buffer__consume(struct ring_buffer *rb);
1458LIBBPF_API int ring_buffer__consume_n(struct ring_buffer *rb, size_t n);
1459LIBBPF_API int ring_buffer__epoll_fd(const struct ring_buffer *rb);
1460
1461/**
1462 * @brief **ring_buffer__ring()** returns the ringbuffer object inside a given
1463 * ringbuffer manager representing a single BPF_MAP_TYPE_RINGBUF map instance.
1464 *
1465 * @param rb A ringbuffer manager object.
1466 * @param idx An index into the ringbuffers contained within the ringbuffer
1467 * manager object. The index is 0-based and corresponds to the order in which
1468 * ring_buffer__add was called.
1469 * @return A ringbuffer object on success; NULL and errno set if the index is
1470 * invalid.
1471 */
1472LIBBPF_API struct ring *ring_buffer__ring(struct ring_buffer *rb,
1473 unsigned int idx);
1474
1475/**
1476 * @brief **ring__consumer_pos()** returns the current consumer position in the
1477 * given ringbuffer.
1478 *
1479 * @param r A ringbuffer object.
1480 * @return The current consumer position.
1481 */
1482LIBBPF_API unsigned long ring__consumer_pos(const struct ring *r);
1483
1484/**
1485 * @brief **ring__producer_pos()** returns the current producer position in the
1486 * given ringbuffer.
1487 *
1488 * @param r A ringbuffer object.
1489 * @return The current producer position.
1490 */
1491LIBBPF_API unsigned long ring__producer_pos(const struct ring *r);
1492
1493/**
1494 * @brief **ring__avail_data_size()** returns the number of bytes in the
1495 * ringbuffer not yet consumed. This has no locking associated with it, so it
1496 * can be inaccurate if operations are ongoing while this is called. However, it
1497 * should still show the correct trend over the long-term.
1498 *
1499 * @param r A ringbuffer object.
1500 * @return The number of bytes not yet consumed.
1501 */
1502LIBBPF_API size_t ring__avail_data_size(const struct ring *r);
1503
1504/**
1505 * @brief **ring__size()** returns the total size of the ringbuffer's map data
1506 * area (excluding special producer/consumer pages). Effectively this gives the
1507 * amount of usable bytes of data inside the ringbuffer.
1508 *
1509 * @param r A ringbuffer object.
1510 * @return The total size of the ringbuffer map data area.
1511 */
1512LIBBPF_API size_t ring__size(const struct ring *r);
1513
1514/**
1515 * @brief **ring__map_fd()** returns the file descriptor underlying the given
1516 * ringbuffer.
1517 *
1518 * @param r A ringbuffer object.
1519 * @return The underlying ringbuffer file descriptor
1520 */
1521LIBBPF_API int ring__map_fd(const struct ring *r);
1522
1523/**
1524 * @brief **ring__consume()** consumes available ringbuffer data without event
1525 * polling.
1526 *
1527 * @param r A ringbuffer object.
1528 * @return The number of records consumed (or INT_MAX, whichever is less), or
1529 * a negative number if any of the callbacks return an error.
1530 */
1531LIBBPF_API int ring__consume(struct ring *r);
1532
1533/**
1534 * @brief **ring__consume_n()** consumes up to a requested amount of items from
1535 * a ringbuffer without event polling.
1536 *
1537 * @param r A ringbuffer object.
1538 * @param n Maximum amount of items to consume.
1539 * @return The number of items consumed, or a negative number if any of the
1540 * callbacks return an error.
1541 */
1542LIBBPF_API int ring__consume_n(struct ring *r, size_t n);
1543
1544struct user_ring_buffer_opts {
1545 size_t sz; /* size of this struct, for forward/backward compatibility */
1546};
1547
1548#define user_ring_buffer_opts__last_field sz
1549
1550/**
1551 * @brief **user_ring_buffer__new()** creates a new instance of a user ring
1552 * buffer.
1553 *
1554 * @param map_fd A file descriptor to a BPF_MAP_TYPE_USER_RINGBUF map.
1555 * @param opts Options for how the ring buffer should be created.
1556 * @return A user ring buffer on success; NULL and errno being set on a
1557 * failure.
1558 */
1559LIBBPF_API struct user_ring_buffer *
1560user_ring_buffer__new(int map_fd, const struct user_ring_buffer_opts *opts);
1561
1562/**
1563 * @brief **user_ring_buffer__reserve()** reserves a pointer to a sample in the
1564 * user ring buffer.
1565 * @param rb A pointer to a user ring buffer.
1566 * @param size The size of the sample, in bytes.
1567 * @return A pointer to an 8-byte aligned reserved region of the user ring
1568 * buffer; NULL, and errno being set if a sample could not be reserved.
1569 *
1570 * This function is *not* thread safe, and callers must synchronize accessing
1571 * this function if there are multiple producers. If a size is requested that
1572 * is larger than the size of the entire ring buffer, errno will be set to
1573 * E2BIG and NULL is returned. If the ring buffer could accommodate the size,
1574 * but currently does not have enough space, errno is set to ENOSPC and NULL is
1575 * returned.
1576 *
1577 * After initializing the sample, callers must invoke
1578 * **user_ring_buffer__submit()** to post the sample to the kernel. Otherwise,
1579 * the sample must be freed with **user_ring_buffer__discard()**.
1580 */
1581LIBBPF_API void *user_ring_buffer__reserve(struct user_ring_buffer *rb, __u32 size);
1582
1583/**
1584 * @brief **user_ring_buffer__reserve_blocking()** reserves a record in the
1585 * ring buffer, possibly blocking for up to @timeout_ms until a sample becomes
1586 * available.
1587 * @param rb The user ring buffer.
1588 * @param size The size of the sample, in bytes.
1589 * @param timeout_ms The amount of time, in milliseconds, for which the caller
1590 * should block when waiting for a sample. -1 causes the caller to block
1591 * indefinitely.
1592 * @return A pointer to an 8-byte aligned reserved region of the user ring
1593 * buffer; NULL, and errno being set if a sample could not be reserved.
1594 *
1595 * This function is *not* thread safe, and callers must synchronize
1596 * accessing this function if there are multiple producers
1597 *
1598 * If **timeout_ms** is -1, the function will block indefinitely until a sample
1599 * becomes available. Otherwise, **timeout_ms** must be non-negative, or errno
1600 * is set to EINVAL, and NULL is returned. If **timeout_ms** is 0, no blocking
1601 * will occur and the function will return immediately after attempting to
1602 * reserve a sample.
1603 *
1604 * If **size** is larger than the size of the entire ring buffer, errno is set
1605 * to E2BIG and NULL is returned. If the ring buffer could accommodate
1606 * **size**, but currently does not have enough space, the caller will block
1607 * until at most **timeout_ms** has elapsed. If insufficient space is available
1608 * at that time, errno is set to ENOSPC, and NULL is returned.
1609 *
1610 * The kernel guarantees that it will wake up this thread to check if
1611 * sufficient space is available in the ring buffer at least once per
1612 * invocation of the **bpf_ringbuf_drain()** helper function, provided that at
1613 * least one sample is consumed, and the BPF program did not invoke the
1614 * function with BPF_RB_NO_WAKEUP. A wakeup may occur sooner than that, but the
1615 * kernel does not guarantee this. If the helper function is invoked with
1616 * BPF_RB_FORCE_WAKEUP, a wakeup event will be sent even if no sample is
1617 * consumed.
1618 *
1619 * When a sample of size **size** is found within **timeout_ms**, a pointer to
1620 * the sample is returned. After initializing the sample, callers must invoke
1621 * **user_ring_buffer__submit()** to post the sample to the ring buffer.
1622 * Otherwise, the sample must be freed with **user_ring_buffer__discard()**.
1623 */
1624LIBBPF_API void *user_ring_buffer__reserve_blocking(struct user_ring_buffer *rb,
1625 __u32 size,
1626 int timeout_ms);
1627
1628/**
1629 * @brief **user_ring_buffer__submit()** submits a previously reserved sample
1630 * into the ring buffer.
1631 * @param rb The user ring buffer.
1632 * @param sample A reserved sample.
1633 *
1634 * It is not necessary to synchronize amongst multiple producers when invoking
1635 * this function.
1636 */
1637LIBBPF_API void user_ring_buffer__submit(struct user_ring_buffer *rb, void *sample);
1638
1639/**
1640 * @brief **user_ring_buffer__discard()** discards a previously reserved sample.
1641 * @param rb The user ring buffer.
1642 * @param sample A reserved sample.
1643 *
1644 * It is not necessary to synchronize amongst multiple producers when invoking
1645 * this function.
1646 */
1647LIBBPF_API void user_ring_buffer__discard(struct user_ring_buffer *rb, void *sample);
1648
1649/**
1650 * @brief **user_ring_buffer__free()** frees a ring buffer that was previously
1651 * created with **user_ring_buffer__new()**.
1652 * @param rb The user ring buffer being freed.
1653 */
1654LIBBPF_API void user_ring_buffer__free(struct user_ring_buffer *rb);
1655
1656/* Perf buffer APIs */
1657struct perf_buffer;
1658
1659typedef void (*perf_buffer_sample_fn)(void *ctx, int cpu,
1660 void *data, __u32 size);
1661typedef void (*perf_buffer_lost_fn)(void *ctx, int cpu, __u64 cnt);
1662
1663/* common use perf buffer options */
1664struct perf_buffer_opts {
1665 size_t sz;
1666 __u32 sample_period;
1667 size_t :0;
1668};
1669#define perf_buffer_opts__last_field sample_period
1670
1671/**
1672 * @brief **perf_buffer__new()** creates BPF perfbuf manager for a specified
1673 * BPF_PERF_EVENT_ARRAY map
1674 * @param map_fd FD of BPF_PERF_EVENT_ARRAY BPF map that will be used by BPF
1675 * code to send data over to user-space
1676 * @param page_cnt number of memory pages allocated for each per-CPU buffer
1677 * @param sample_cb function called on each received data record
1678 * @param lost_cb function called when record loss has occurred
1679 * @param ctx user-provided extra context passed into *sample_cb* and *lost_cb*
1680 * @param opts optional parameters for the perf buffer, can be null
1681 * @return a new instance of struct perf_buffer on success, NULL on error with
1682 * *errno* containing an error code
1683 */
1684LIBBPF_API struct perf_buffer *
1685perf_buffer__new(int map_fd, size_t page_cnt,
1686 perf_buffer_sample_fn sample_cb, perf_buffer_lost_fn lost_cb, void *ctx,
1687 const struct perf_buffer_opts *opts);
1688
1689enum bpf_perf_event_ret {
1690 LIBBPF_PERF_EVENT_DONE = 0,
1691 LIBBPF_PERF_EVENT_ERROR = -1,
1692 LIBBPF_PERF_EVENT_CONT = -2,
1693};
1694
1695struct perf_event_header;
1696
1697typedef enum bpf_perf_event_ret
1698(*perf_buffer_event_fn)(void *ctx, int cpu, struct perf_event_header *event);
1699
1700/* raw perf buffer options, giving most power and control */
1701struct perf_buffer_raw_opts {
1702 size_t sz;
1703 long :0;
1704 long :0;
1705 /* if cpu_cnt == 0, open all on all possible CPUs (up to the number of
1706 * max_entries of given PERF_EVENT_ARRAY map)
1707 */
1708 int cpu_cnt;
1709 /* if cpu_cnt > 0, cpus is an array of CPUs to open ring buffers on */
1710 int *cpus;
1711 /* if cpu_cnt > 0, map_keys specify map keys to set per-CPU FDs for */
1712 int *map_keys;
1713};
1714#define perf_buffer_raw_opts__last_field map_keys
1715
1716struct perf_event_attr;
1717
1718LIBBPF_API struct perf_buffer *
1719perf_buffer__new_raw(int map_fd, size_t page_cnt, struct perf_event_attr *attr,
1720 perf_buffer_event_fn event_cb, void *ctx,
1721 const struct perf_buffer_raw_opts *opts);
1722
1723LIBBPF_API void perf_buffer__free(struct perf_buffer *pb);
1724LIBBPF_API int perf_buffer__epoll_fd(const struct perf_buffer *pb);
1725LIBBPF_API int perf_buffer__poll(struct perf_buffer *pb, int timeout_ms);
1726LIBBPF_API int perf_buffer__consume(struct perf_buffer *pb);
1727LIBBPF_API int perf_buffer__consume_buffer(struct perf_buffer *pb, size_t buf_idx);
1728LIBBPF_API size_t perf_buffer__buffer_cnt(const struct perf_buffer *pb);
1729LIBBPF_API int perf_buffer__buffer_fd(const struct perf_buffer *pb, size_t buf_idx);
1730/**
1731 * @brief **perf_buffer__buffer()** returns the per-cpu raw mmap()'ed underlying
1732 * memory region of the ring buffer.
1733 * This ring buffer can be used to implement a custom events consumer.
1734 * The ring buffer starts with the *struct perf_event_mmap_page*, which
1735 * holds the ring buffer management fields, when accessing the header
1736 * structure it's important to be SMP aware.
1737 * You can refer to *perf_event_read_simple* for a simple example.
1738 * @param pb the perf buffer structure
1739 * @param buf_idx the buffer index to retrieve
1740 * @param buf (out) gets the base pointer of the mmap()'ed memory
1741 * @param buf_size (out) gets the size of the mmap()'ed region
1742 * @return 0 on success, negative error code for failure
1743 */
1744LIBBPF_API int perf_buffer__buffer(struct perf_buffer *pb, int buf_idx, void **buf,
1745 size_t *buf_size);
1746
1747struct bpf_prog_linfo;
1748struct bpf_prog_info;
1749
1750LIBBPF_API void bpf_prog_linfo__free(struct bpf_prog_linfo *prog_linfo);
1751LIBBPF_API struct bpf_prog_linfo *
1752bpf_prog_linfo__new(const struct bpf_prog_info *info);
1753LIBBPF_API const struct bpf_line_info *
1754bpf_prog_linfo__lfind_addr_func(const struct bpf_prog_linfo *prog_linfo,
1755 __u64 addr, __u32 func_idx, __u32 nr_skip);
1756LIBBPF_API const struct bpf_line_info *
1757bpf_prog_linfo__lfind(const struct bpf_prog_linfo *prog_linfo,
1758 __u32 insn_off, __u32 nr_skip);
1759
1760/*
1761 * Probe for supported system features
1762 *
1763 * Note that running many of these probes in a short amount of time can cause
1764 * the kernel to reach the maximal size of lockable memory allowed for the
1765 * user, causing subsequent probes to fail. In this case, the caller may want
1766 * to adjust that limit with setrlimit().
1767 */
1768
1769/**
1770 * @brief **libbpf_probe_bpf_prog_type()** detects if host kernel supports
1771 * BPF programs of a given type.
1772 * @param prog_type BPF program type to detect kernel support for
1773 * @param opts reserved for future extensibility, should be NULL
1774 * @return 1, if given program type is supported; 0, if given program type is
1775 * not supported; negative error code if feature detection failed or can't be
1776 * performed
1777 *
1778 * Make sure the process has required set of CAP_* permissions (or runs as
1779 * root) when performing feature checking.
1780 */
1781LIBBPF_API int libbpf_probe_bpf_prog_type(enum bpf_prog_type prog_type, const void *opts);
1782/**
1783 * @brief **libbpf_probe_bpf_map_type()** detects if host kernel supports
1784 * BPF maps of a given type.
1785 * @param map_type BPF map type to detect kernel support for
1786 * @param opts reserved for future extensibility, should be NULL
1787 * @return 1, if given map type is supported; 0, if given map type is
1788 * not supported; negative error code if feature detection failed or can't be
1789 * performed
1790 *
1791 * Make sure the process has required set of CAP_* permissions (or runs as
1792 * root) when performing feature checking.
1793 */
1794LIBBPF_API int libbpf_probe_bpf_map_type(enum bpf_map_type map_type, const void *opts);
1795/**
1796 * @brief **libbpf_probe_bpf_helper()** detects if host kernel supports the
1797 * use of a given BPF helper from specified BPF program type.
1798 * @param prog_type BPF program type used to check the support of BPF helper
1799 * @param helper_id BPF helper ID (enum bpf_func_id) to check support for
1800 * @param opts reserved for future extensibility, should be NULL
1801 * @return 1, if given combination of program type and helper is supported; 0,
1802 * if the combination is not supported; negative error code if feature
1803 * detection for provided input arguments failed or can't be performed
1804 *
1805 * Make sure the process has required set of CAP_* permissions (or runs as
1806 * root) when performing feature checking.
1807 */
1808LIBBPF_API int libbpf_probe_bpf_helper(enum bpf_prog_type prog_type,
1809 enum bpf_func_id helper_id, const void *opts);
1810
1811/**
1812 * @brief **libbpf_num_possible_cpus()** is a helper function to get the
1813 * number of possible CPUs that the host kernel supports and expects.
1814 * @return number of possible CPUs; or error code on failure
1815 *
1816 * Example usage:
1817 *
1818 * int ncpus = libbpf_num_possible_cpus();
1819 * if (ncpus < 0) {
1820 * // error handling
1821 * }
1822 * long values[ncpus];
1823 * bpf_map_lookup_elem(per_cpu_map_fd, key, values);
1824 */
1825LIBBPF_API int libbpf_num_possible_cpus(void);
1826
1827struct bpf_map_skeleton {
1828 const char *name;
1829 struct bpf_map **map;
1830 void **mmaped;
1831 struct bpf_link **link;
1832};
1833
1834struct bpf_prog_skeleton {
1835 const char *name;
1836 struct bpf_program **prog;
1837 struct bpf_link **link;
1838};
1839
1840struct bpf_object_skeleton {
1841 size_t sz; /* size of this struct, for forward/backward compatibility */
1842
1843 const char *name;
1844 const void *data;
1845 size_t data_sz;
1846
1847 struct bpf_object **obj;
1848
1849 int map_cnt;
1850 int map_skel_sz; /* sizeof(struct bpf_map_skeleton) */
1851 struct bpf_map_skeleton *maps;
1852
1853 int prog_cnt;
1854 int prog_skel_sz; /* sizeof(struct bpf_prog_skeleton) */
1855 struct bpf_prog_skeleton *progs;
1856};
1857
1858LIBBPF_API int
1859bpf_object__open_skeleton(struct bpf_object_skeleton *s,
1860 const struct bpf_object_open_opts *opts);
1861LIBBPF_API int bpf_object__load_skeleton(struct bpf_object_skeleton *s);
1862LIBBPF_API int bpf_object__attach_skeleton(struct bpf_object_skeleton *s);
1863LIBBPF_API void bpf_object__detach_skeleton(struct bpf_object_skeleton *s);
1864LIBBPF_API void bpf_object__destroy_skeleton(struct bpf_object_skeleton *s);
1865
1866struct bpf_var_skeleton {
1867 const char *name;
1868 struct bpf_map **map;
1869 void **addr;
1870};
1871
1872struct bpf_object_subskeleton {
1873 size_t sz; /* size of this struct, for forward/backward compatibility */
1874
1875 const struct bpf_object *obj;
1876
1877 int map_cnt;
1878 int map_skel_sz; /* sizeof(struct bpf_map_skeleton) */
1879 struct bpf_map_skeleton *maps;
1880
1881 int prog_cnt;
1882 int prog_skel_sz; /* sizeof(struct bpf_prog_skeleton) */
1883 struct bpf_prog_skeleton *progs;
1884
1885 int var_cnt;
1886 int var_skel_sz; /* sizeof(struct bpf_var_skeleton) */
1887 struct bpf_var_skeleton *vars;
1888};
1889
1890LIBBPF_API int
1891bpf_object__open_subskeleton(struct bpf_object_subskeleton *s);
1892LIBBPF_API void
1893bpf_object__destroy_subskeleton(struct bpf_object_subskeleton *s);
1894
1895struct gen_loader_opts {
1896 size_t sz; /* size of this struct, for forward/backward compatibility */
1897 const char *data;
1898 const char *insns;
1899 __u32 data_sz;
1900 __u32 insns_sz;
1901 bool gen_hash;
1902};
1903
1904#define gen_loader_opts__last_field gen_hash
1905LIBBPF_API int bpf_object__gen_loader(struct bpf_object *obj,
1906 struct gen_loader_opts *opts);
1907
1908enum libbpf_tristate {
1909 TRI_NO = 0,
1910 TRI_YES = 1,
1911 TRI_MODULE = 2,
1912};
1913
1914struct bpf_linker_opts {
1915 /* size of this struct, for forward/backward compatibility */
1916 size_t sz;
1917};
1918#define bpf_linker_opts__last_field sz
1919
1920struct bpf_linker_file_opts {
1921 /* size of this struct, for forward/backward compatibility */
1922 size_t sz;
1923};
1924#define bpf_linker_file_opts__last_field sz
1925
1926struct bpf_linker;
1927
1928LIBBPF_API struct bpf_linker *bpf_linker__new(const char *filename, struct bpf_linker_opts *opts);
1929LIBBPF_API struct bpf_linker *bpf_linker__new_fd(int fd, struct bpf_linker_opts *opts);
1930LIBBPF_API int bpf_linker__add_file(struct bpf_linker *linker,
1931 const char *filename,
1932 const struct bpf_linker_file_opts *opts);
1933LIBBPF_API int bpf_linker__add_fd(struct bpf_linker *linker, int fd,
1934 const struct bpf_linker_file_opts *opts);
1935LIBBPF_API int bpf_linker__add_buf(struct bpf_linker *linker, void *buf, size_t buf_sz,
1936 const struct bpf_linker_file_opts *opts);
1937LIBBPF_API int bpf_linker__finalize(struct bpf_linker *linker);
1938LIBBPF_API void bpf_linker__free(struct bpf_linker *linker);
1939
1940/*
1941 * Custom handling of BPF program's SEC() definitions
1942 */
1943
1944struct bpf_prog_load_opts; /* defined in bpf.h */
1945
1946/* Called during bpf_object__open() for each recognized BPF program. Callback
1947 * can use various bpf_program__set_*() setters to adjust whatever properties
1948 * are necessary.
1949 */
1950typedef int (*libbpf_prog_setup_fn_t)(struct bpf_program *prog, long cookie);
1951
1952/* Called right before libbpf performs bpf_prog_load() to load BPF program
1953 * into the kernel. Callback can adjust opts as necessary.
1954 */
1955typedef int (*libbpf_prog_prepare_load_fn_t)(struct bpf_program *prog,
1956 struct bpf_prog_load_opts *opts, long cookie);
1957
1958/* Called during skeleton attach or through bpf_program__attach(). If
1959 * auto-attach is not supported, callback should return 0 and set link to
1960 * NULL (it's not considered an error during skeleton attach, but it will be
1961 * an error for bpf_program__attach() calls). On error, error should be
1962 * returned directly and link set to NULL. On success, return 0 and set link
1963 * to a valid struct bpf_link.
1964 */
1965typedef int (*libbpf_prog_attach_fn_t)(const struct bpf_program *prog, long cookie,
1966 struct bpf_link **link);
1967
1968struct libbpf_prog_handler_opts {
1969 /* size of this struct, for forward/backward compatibility */
1970 size_t sz;
1971 /* User-provided value that is passed to prog_setup_fn,
1972 * prog_prepare_load_fn, and prog_attach_fn callbacks. Allows user to
1973 * register one set of callbacks for multiple SEC() definitions and
1974 * still be able to distinguish them, if necessary. For example,
1975 * libbpf itself is using this to pass necessary flags (e.g.,
1976 * sleepable flag) to a common internal SEC() handler.
1977 */
1978 long cookie;
1979 /* BPF program initialization callback (see libbpf_prog_setup_fn_t).
1980 * Callback is optional, pass NULL if it's not necessary.
1981 */
1982 libbpf_prog_setup_fn_t prog_setup_fn;
1983 /* BPF program loading callback (see libbpf_prog_prepare_load_fn_t).
1984 * Callback is optional, pass NULL if it's not necessary.
1985 */
1986 libbpf_prog_prepare_load_fn_t prog_prepare_load_fn;
1987 /* BPF program attach callback (see libbpf_prog_attach_fn_t).
1988 * Callback is optional, pass NULL if it's not necessary.
1989 */
1990 libbpf_prog_attach_fn_t prog_attach_fn;
1991};
1992#define libbpf_prog_handler_opts__last_field prog_attach_fn
1993
1994/**
1995 * @brief **libbpf_register_prog_handler()** registers a custom BPF program
1996 * SEC() handler.
1997 * @param sec section prefix for which custom handler is registered
1998 * @param prog_type BPF program type associated with specified section
1999 * @param exp_attach_type Expected BPF attach type associated with specified section
2000 * @param opts optional cookie, callbacks, and other extra options
2001 * @return Non-negative handler ID is returned on success. This handler ID has
2002 * to be passed to *libbpf_unregister_prog_handler()* to unregister such
2003 * custom handler. Negative error code is returned on error.
2004 *
2005 * *sec* defines which SEC() definitions are handled by this custom handler
2006 * registration. *sec* can have few different forms:
2007 * - if *sec* is just a plain string (e.g., "abc"), it will match only
2008 * SEC("abc"). If BPF program specifies SEC("abc/whatever") it will result
2009 * in an error;
2010 * - if *sec* is of the form "abc/", proper SEC() form is
2011 * SEC("abc/something"), where acceptable "something" should be checked by
2012 * *prog_init_fn* callback, if there are additional restrictions;
2013 * - if *sec* is of the form "abc+", it will successfully match both
2014 * SEC("abc") and SEC("abc/whatever") forms;
2015 * - if *sec* is NULL, custom handler is registered for any BPF program that
2016 * doesn't match any of the registered (custom or libbpf's own) SEC()
2017 * handlers. There could be only one such generic custom handler registered
2018 * at any given time.
2019 *
2020 * All custom handlers (except the one with *sec* == NULL) are processed
2021 * before libbpf's own SEC() handlers. It is allowed to "override" libbpf's
2022 * SEC() handlers by registering custom ones for the same section prefix
2023 * (i.e., it's possible to have custom SEC("perf_event/LLC-load-misses")
2024 * handler).
2025 *
2026 * Note, like much of global libbpf APIs (e.g., libbpf_set_print(),
2027 * libbpf_set_strict_mode(), etc)) these APIs are not thread-safe. User needs
2028 * to ensure synchronization if there is a risk of running this API from
2029 * multiple threads simultaneously.
2030 */
2031LIBBPF_API int libbpf_register_prog_handler(const char *sec,
2032 enum bpf_prog_type prog_type,
2033 enum bpf_attach_type exp_attach_type,
2034 const struct libbpf_prog_handler_opts *opts);
2035/**
2036 * @brief *libbpf_unregister_prog_handler()* unregisters previously registered
2037 * custom BPF program SEC() handler.
2038 * @param handler_id handler ID returned by *libbpf_register_prog_handler()*
2039 * after successful registration
2040 * @return 0 on success, negative error code if handler isn't found
2041 *
2042 * Note, like much of global libbpf APIs (e.g., libbpf_set_print(),
2043 * libbpf_set_strict_mode(), etc)) these APIs are not thread-safe. User needs
2044 * to ensure synchronization if there is a risk of running this API from
2045 * multiple threads simultaneously.
2046 */
2047LIBBPF_API int libbpf_unregister_prog_handler(int handler_id);
2048
2049/**
2050 * @brief **bpf_program__clone()** loads a single BPF program from a prepared
2051 * BPF object into the kernel, returning its file descriptor.
2052 *
2053 * The BPF object must have been previously prepared with
2054 * **bpf_object__prepare()**. If @opts is provided, any non-zero field
2055 * overrides the defaults derived from the program/object internals.
2056 * If @opts is NULL, all fields are populated automatically.
2057 *
2058 * The returned FD is owned by the caller and must be closed with close().
2059 *
2060 * @param prog BPF program from a prepared object
2061 * @param opts Optional load options; non-zero fields override defaults
2062 * @return program FD (>= 0) on success; negative error code on failure
2063 */
2064LIBBPF_API int bpf_program__clone(struct bpf_program *prog, const struct bpf_prog_load_opts *opts);
2065
2066#ifdef __cplusplus
2067} /* extern "C" */
2068#endif
2069
2070#endif /* __LIBBPF_LIBBPF_H */