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 #ifdef __cplusplus 21 extern "C" { 22 #endif 23 24 #ifndef LIBBPF_API 25 #define LIBBPF_API __attribute__((visibility("default"))) 26 #endif 27 28 enum libbpf_errno { 29 __LIBBPF_ERRNO__START = 4000, 30 31 /* Something wrong in libelf */ 32 LIBBPF_ERRNO__LIBELF = __LIBBPF_ERRNO__START, 33 LIBBPF_ERRNO__FORMAT, /* BPF object format invalid */ 34 LIBBPF_ERRNO__KVERSION, /* Incorrect or no 'version' section */ 35 LIBBPF_ERRNO__ENDIAN, /* Endian mismatch */ 36 LIBBPF_ERRNO__INTERNAL, /* Internal error in libbpf */ 37 LIBBPF_ERRNO__RELOC, /* Relocation failed */ 38 LIBBPF_ERRNO__LOAD, /* Load program failure for unknown reason */ 39 LIBBPF_ERRNO__VERIFY, /* Kernel verifier blocks program loading */ 40 LIBBPF_ERRNO__PROG2BIG, /* Program too big */ 41 LIBBPF_ERRNO__KVER, /* Incorrect kernel version */ 42 LIBBPF_ERRNO__PROGTYPE, /* Kernel doesn't support this program type */ 43 LIBBPF_ERRNO__WRNGPID, /* Wrong pid in netlink message */ 44 LIBBPF_ERRNO__INVSEQ, /* Invalid netlink sequence */ 45 LIBBPF_ERRNO__NLPARSE, /* netlink parsing error */ 46 __LIBBPF_ERRNO__END, 47 }; 48 49 LIBBPF_API int libbpf_strerror(int err, char *buf, size_t size); 50 51 enum libbpf_print_level { 52 LIBBPF_WARN, 53 LIBBPF_INFO, 54 LIBBPF_DEBUG, 55 }; 56 57 typedef int (*libbpf_print_fn_t)(enum libbpf_print_level level, 58 const char *, va_list ap); 59 60 LIBBPF_API libbpf_print_fn_t libbpf_set_print(libbpf_print_fn_t fn); 61 62 /* Hide internal to user */ 63 struct bpf_object; 64 65 struct bpf_object_open_attr { 66 const char *file; 67 enum bpf_prog_type prog_type; 68 }; 69 70 LIBBPF_API struct bpf_object *bpf_object__open(const char *path); 71 LIBBPF_API struct bpf_object * 72 bpf_object__open_xattr(struct bpf_object_open_attr *attr); 73 struct bpf_object *__bpf_object__open_xattr(struct bpf_object_open_attr *attr, 74 int flags); 75 LIBBPF_API struct bpf_object *bpf_object__open_buffer(void *obj_buf, 76 size_t obj_buf_sz, 77 const char *name); 78 int bpf_object__section_size(const struct bpf_object *obj, const char *name, 79 __u32 *size); 80 int bpf_object__variable_offset(const struct bpf_object *obj, const char *name, 81 __u32 *off); 82 LIBBPF_API int bpf_object__pin_maps(struct bpf_object *obj, const char *path); 83 LIBBPF_API int bpf_object__unpin_maps(struct bpf_object *obj, 84 const char *path); 85 LIBBPF_API int bpf_object__pin_programs(struct bpf_object *obj, 86 const char *path); 87 LIBBPF_API int bpf_object__unpin_programs(struct bpf_object *obj, 88 const char *path); 89 LIBBPF_API int bpf_object__pin(struct bpf_object *object, const char *path); 90 LIBBPF_API void bpf_object__close(struct bpf_object *object); 91 92 struct bpf_object_load_attr { 93 struct bpf_object *obj; 94 int log_level; 95 const char *target_btf_path; 96 }; 97 98 /* Load/unload object into/from kernel */ 99 LIBBPF_API int bpf_object__load(struct bpf_object *obj); 100 LIBBPF_API int bpf_object__load_xattr(struct bpf_object_load_attr *attr); 101 LIBBPF_API int bpf_object__unload(struct bpf_object *obj); 102 LIBBPF_API const char *bpf_object__name(const struct bpf_object *obj); 103 LIBBPF_API unsigned int bpf_object__kversion(const struct bpf_object *obj); 104 105 struct btf; 106 LIBBPF_API struct btf *bpf_object__btf(const struct bpf_object *obj); 107 LIBBPF_API int bpf_object__btf_fd(const struct bpf_object *obj); 108 109 LIBBPF_API struct bpf_program * 110 bpf_object__find_program_by_title(const struct bpf_object *obj, 111 const char *title); 112 113 LIBBPF_API struct bpf_object *bpf_object__next(struct bpf_object *prev); 114 #define bpf_object__for_each_safe(pos, tmp) \ 115 for ((pos) = bpf_object__next(NULL), \ 116 (tmp) = bpf_object__next(pos); \ 117 (pos) != NULL; \ 118 (pos) = (tmp), (tmp) = bpf_object__next(tmp)) 119 120 typedef void (*bpf_object_clear_priv_t)(struct bpf_object *, void *); 121 LIBBPF_API int bpf_object__set_priv(struct bpf_object *obj, void *priv, 122 bpf_object_clear_priv_t clear_priv); 123 LIBBPF_API void *bpf_object__priv(const struct bpf_object *prog); 124 125 LIBBPF_API int 126 libbpf_prog_type_by_name(const char *name, enum bpf_prog_type *prog_type, 127 enum bpf_attach_type *expected_attach_type); 128 LIBBPF_API int libbpf_attach_type_by_name(const char *name, 129 enum bpf_attach_type *attach_type); 130 131 /* Accessors of bpf_program */ 132 struct bpf_program; 133 LIBBPF_API struct bpf_program *bpf_program__next(struct bpf_program *prog, 134 const struct bpf_object *obj); 135 136 #define bpf_object__for_each_program(pos, obj) \ 137 for ((pos) = bpf_program__next(NULL, (obj)); \ 138 (pos) != NULL; \ 139 (pos) = bpf_program__next((pos), (obj))) 140 141 LIBBPF_API struct bpf_program *bpf_program__prev(struct bpf_program *prog, 142 const struct bpf_object *obj); 143 144 typedef void (*bpf_program_clear_priv_t)(struct bpf_program *, void *); 145 146 LIBBPF_API int bpf_program__set_priv(struct bpf_program *prog, void *priv, 147 bpf_program_clear_priv_t clear_priv); 148 149 LIBBPF_API void *bpf_program__priv(const struct bpf_program *prog); 150 LIBBPF_API void bpf_program__set_ifindex(struct bpf_program *prog, 151 __u32 ifindex); 152 153 LIBBPF_API const char *bpf_program__title(const struct bpf_program *prog, 154 bool needs_copy); 155 156 LIBBPF_API int bpf_program__load(struct bpf_program *prog, char *license, 157 __u32 kern_version); 158 LIBBPF_API int bpf_program__fd(const struct bpf_program *prog); 159 LIBBPF_API int bpf_program__pin_instance(struct bpf_program *prog, 160 const char *path, 161 int instance); 162 LIBBPF_API int bpf_program__unpin_instance(struct bpf_program *prog, 163 const char *path, 164 int instance); 165 LIBBPF_API int bpf_program__pin(struct bpf_program *prog, const char *path); 166 LIBBPF_API int bpf_program__unpin(struct bpf_program *prog, const char *path); 167 LIBBPF_API void bpf_program__unload(struct bpf_program *prog); 168 169 struct bpf_link; 170 171 LIBBPF_API int bpf_link__destroy(struct bpf_link *link); 172 173 LIBBPF_API struct bpf_link * 174 bpf_program__attach_perf_event(struct bpf_program *prog, int pfd); 175 LIBBPF_API struct bpf_link * 176 bpf_program__attach_kprobe(struct bpf_program *prog, bool retprobe, 177 const char *func_name); 178 LIBBPF_API struct bpf_link * 179 bpf_program__attach_uprobe(struct bpf_program *prog, bool retprobe, 180 pid_t pid, const char *binary_path, 181 size_t func_offset); 182 LIBBPF_API struct bpf_link * 183 bpf_program__attach_tracepoint(struct bpf_program *prog, 184 const char *tp_category, 185 const char *tp_name); 186 LIBBPF_API struct bpf_link * 187 bpf_program__attach_raw_tracepoint(struct bpf_program *prog, 188 const char *tp_name); 189 190 struct bpf_insn; 191 192 /* 193 * Libbpf allows callers to adjust BPF programs before being loaded 194 * into kernel. One program in an object file can be transformed into 195 * multiple variants to be attached to different hooks. 196 * 197 * bpf_program_prep_t, bpf_program__set_prep and bpf_program__nth_fd 198 * form an API for this purpose. 199 * 200 * - bpf_program_prep_t: 201 * Defines a 'preprocessor', which is a caller defined function 202 * passed to libbpf through bpf_program__set_prep(), and will be 203 * called before program is loaded. The processor should adjust 204 * the program one time for each instance according to the instance id 205 * passed to it. 206 * 207 * - bpf_program__set_prep: 208 * Attaches a preprocessor to a BPF program. The number of instances 209 * that should be created is also passed through this function. 210 * 211 * - bpf_program__nth_fd: 212 * After the program is loaded, get resulting FD of a given instance 213 * of the BPF program. 214 * 215 * If bpf_program__set_prep() is not used, the program would be loaded 216 * without adjustment during bpf_object__load(). The program has only 217 * one instance. In this case bpf_program__fd(prog) is equal to 218 * bpf_program__nth_fd(prog, 0). 219 */ 220 221 struct bpf_prog_prep_result { 222 /* 223 * If not NULL, load new instruction array. 224 * If set to NULL, don't load this instance. 225 */ 226 struct bpf_insn *new_insn_ptr; 227 int new_insn_cnt; 228 229 /* If not NULL, result FD is written to it. */ 230 int *pfd; 231 }; 232 233 /* 234 * Parameters of bpf_program_prep_t: 235 * - prog: The bpf_program being loaded. 236 * - n: Index of instance being generated. 237 * - insns: BPF instructions array. 238 * - insns_cnt:Number of instructions in insns. 239 * - res: Output parameter, result of transformation. 240 * 241 * Return value: 242 * - Zero: pre-processing success. 243 * - Non-zero: pre-processing error, stop loading. 244 */ 245 typedef int (*bpf_program_prep_t)(struct bpf_program *prog, int n, 246 struct bpf_insn *insns, int insns_cnt, 247 struct bpf_prog_prep_result *res); 248 249 LIBBPF_API int bpf_program__set_prep(struct bpf_program *prog, int nr_instance, 250 bpf_program_prep_t prep); 251 252 LIBBPF_API int bpf_program__nth_fd(const struct bpf_program *prog, int n); 253 254 /* 255 * Adjust type of BPF program. Default is kprobe. 256 */ 257 LIBBPF_API int bpf_program__set_socket_filter(struct bpf_program *prog); 258 LIBBPF_API int bpf_program__set_tracepoint(struct bpf_program *prog); 259 LIBBPF_API int bpf_program__set_raw_tracepoint(struct bpf_program *prog); 260 LIBBPF_API int bpf_program__set_kprobe(struct bpf_program *prog); 261 LIBBPF_API int bpf_program__set_sched_cls(struct bpf_program *prog); 262 LIBBPF_API int bpf_program__set_sched_act(struct bpf_program *prog); 263 LIBBPF_API int bpf_program__set_xdp(struct bpf_program *prog); 264 LIBBPF_API int bpf_program__set_perf_event(struct bpf_program *prog); 265 LIBBPF_API void bpf_program__set_type(struct bpf_program *prog, 266 enum bpf_prog_type type); 267 LIBBPF_API void 268 bpf_program__set_expected_attach_type(struct bpf_program *prog, 269 enum bpf_attach_type type); 270 271 LIBBPF_API bool bpf_program__is_socket_filter(const struct bpf_program *prog); 272 LIBBPF_API bool bpf_program__is_tracepoint(const struct bpf_program *prog); 273 LIBBPF_API bool bpf_program__is_raw_tracepoint(const struct bpf_program *prog); 274 LIBBPF_API bool bpf_program__is_kprobe(const struct bpf_program *prog); 275 LIBBPF_API bool bpf_program__is_sched_cls(const struct bpf_program *prog); 276 LIBBPF_API bool bpf_program__is_sched_act(const struct bpf_program *prog); 277 LIBBPF_API bool bpf_program__is_xdp(const struct bpf_program *prog); 278 LIBBPF_API bool bpf_program__is_perf_event(const struct bpf_program *prog); 279 280 /* 281 * No need for __attribute__((packed)), all members of 'bpf_map_def' 282 * are all aligned. In addition, using __attribute__((packed)) 283 * would trigger a -Wpacked warning message, and lead to an error 284 * if -Werror is set. 285 */ 286 struct bpf_map_def { 287 unsigned int type; 288 unsigned int key_size; 289 unsigned int value_size; 290 unsigned int max_entries; 291 unsigned int map_flags; 292 }; 293 294 /* 295 * The 'struct bpf_map' in include/linux/bpf.h is internal to the kernel, 296 * so no need to worry about a name clash. 297 */ 298 struct bpf_map; 299 LIBBPF_API struct bpf_map * 300 bpf_object__find_map_by_name(const struct bpf_object *obj, const char *name); 301 302 LIBBPF_API int 303 bpf_object__find_map_fd_by_name(const struct bpf_object *obj, const char *name); 304 305 /* 306 * Get bpf_map through the offset of corresponding struct bpf_map_def 307 * in the BPF object file. 308 */ 309 LIBBPF_API struct bpf_map * 310 bpf_object__find_map_by_offset(struct bpf_object *obj, size_t offset); 311 312 LIBBPF_API struct bpf_map * 313 bpf_map__next(const struct bpf_map *map, const struct bpf_object *obj); 314 #define bpf_object__for_each_map(pos, obj) \ 315 for ((pos) = bpf_map__next(NULL, (obj)); \ 316 (pos) != NULL; \ 317 (pos) = bpf_map__next((pos), (obj))) 318 #define bpf_map__for_each bpf_object__for_each_map 319 320 LIBBPF_API struct bpf_map * 321 bpf_map__prev(const struct bpf_map *map, const struct bpf_object *obj); 322 323 LIBBPF_API int bpf_map__fd(const struct bpf_map *map); 324 LIBBPF_API const struct bpf_map_def *bpf_map__def(const struct bpf_map *map); 325 LIBBPF_API const char *bpf_map__name(const struct bpf_map *map); 326 LIBBPF_API __u32 bpf_map__btf_key_type_id(const struct bpf_map *map); 327 LIBBPF_API __u32 bpf_map__btf_value_type_id(const struct bpf_map *map); 328 329 typedef void (*bpf_map_clear_priv_t)(struct bpf_map *, void *); 330 LIBBPF_API int bpf_map__set_priv(struct bpf_map *map, void *priv, 331 bpf_map_clear_priv_t clear_priv); 332 LIBBPF_API void *bpf_map__priv(const struct bpf_map *map); 333 LIBBPF_API int bpf_map__reuse_fd(struct bpf_map *map, int fd); 334 LIBBPF_API int bpf_map__resize(struct bpf_map *map, __u32 max_entries); 335 LIBBPF_API bool bpf_map__is_offload_neutral(const struct bpf_map *map); 336 LIBBPF_API bool bpf_map__is_internal(const struct bpf_map *map); 337 LIBBPF_API void bpf_map__set_ifindex(struct bpf_map *map, __u32 ifindex); 338 LIBBPF_API int bpf_map__pin(struct bpf_map *map, const char *path); 339 LIBBPF_API int bpf_map__unpin(struct bpf_map *map, const char *path); 340 341 LIBBPF_API int bpf_map__set_inner_map_fd(struct bpf_map *map, int fd); 342 343 LIBBPF_API long libbpf_get_error(const void *ptr); 344 345 struct bpf_prog_load_attr { 346 const char *file; 347 enum bpf_prog_type prog_type; 348 enum bpf_attach_type expected_attach_type; 349 int ifindex; 350 int log_level; 351 int prog_flags; 352 }; 353 354 LIBBPF_API int bpf_prog_load_xattr(const struct bpf_prog_load_attr *attr, 355 struct bpf_object **pobj, int *prog_fd); 356 LIBBPF_API int bpf_prog_load(const char *file, enum bpf_prog_type type, 357 struct bpf_object **pobj, int *prog_fd); 358 359 LIBBPF_API int bpf_set_link_xdp_fd(int ifindex, int fd, __u32 flags); 360 LIBBPF_API int bpf_get_link_xdp_id(int ifindex, __u32 *prog_id, __u32 flags); 361 362 struct perf_buffer; 363 364 typedef void (*perf_buffer_sample_fn)(void *ctx, int cpu, 365 void *data, __u32 size); 366 typedef void (*perf_buffer_lost_fn)(void *ctx, int cpu, __u64 cnt); 367 368 /* common use perf buffer options */ 369 struct perf_buffer_opts { 370 /* if specified, sample_cb is called for each sample */ 371 perf_buffer_sample_fn sample_cb; 372 /* if specified, lost_cb is called for each batch of lost samples */ 373 perf_buffer_lost_fn lost_cb; 374 /* ctx is provided to sample_cb and lost_cb */ 375 void *ctx; 376 }; 377 378 LIBBPF_API struct perf_buffer * 379 perf_buffer__new(int map_fd, size_t page_cnt, 380 const struct perf_buffer_opts *opts); 381 382 enum bpf_perf_event_ret { 383 LIBBPF_PERF_EVENT_DONE = 0, 384 LIBBPF_PERF_EVENT_ERROR = -1, 385 LIBBPF_PERF_EVENT_CONT = -2, 386 }; 387 388 struct perf_event_header; 389 390 typedef enum bpf_perf_event_ret 391 (*perf_buffer_event_fn)(void *ctx, int cpu, struct perf_event_header *event); 392 393 /* raw perf buffer options, giving most power and control */ 394 struct perf_buffer_raw_opts { 395 /* perf event attrs passed directly into perf_event_open() */ 396 struct perf_event_attr *attr; 397 /* raw event callback */ 398 perf_buffer_event_fn event_cb; 399 /* ctx is provided to event_cb */ 400 void *ctx; 401 /* if cpu_cnt == 0, open all on all possible CPUs (up to the number of 402 * max_entries of given PERF_EVENT_ARRAY map) 403 */ 404 int cpu_cnt; 405 /* if cpu_cnt > 0, cpus is an array of CPUs to open ring buffers on */ 406 int *cpus; 407 /* if cpu_cnt > 0, map_keys specify map keys to set per-CPU FDs for */ 408 int *map_keys; 409 }; 410 411 LIBBPF_API struct perf_buffer * 412 perf_buffer__new_raw(int map_fd, size_t page_cnt, 413 const struct perf_buffer_raw_opts *opts); 414 415 LIBBPF_API void perf_buffer__free(struct perf_buffer *pb); 416 LIBBPF_API int perf_buffer__poll(struct perf_buffer *pb, int timeout_ms); 417 418 typedef enum bpf_perf_event_ret 419 (*bpf_perf_event_print_t)(struct perf_event_header *hdr, 420 void *private_data); 421 LIBBPF_API enum bpf_perf_event_ret 422 bpf_perf_event_read_simple(void *mmap_mem, size_t mmap_size, size_t page_size, 423 void **copy_mem, size_t *copy_size, 424 bpf_perf_event_print_t fn, void *private_data); 425 426 struct nlattr; 427 typedef int (*libbpf_dump_nlmsg_t)(void *cookie, void *msg, struct nlattr **tb); 428 int libbpf_netlink_open(unsigned int *nl_pid); 429 int libbpf_nl_get_link(int sock, unsigned int nl_pid, 430 libbpf_dump_nlmsg_t dump_link_nlmsg, void *cookie); 431 int libbpf_nl_get_class(int sock, unsigned int nl_pid, int ifindex, 432 libbpf_dump_nlmsg_t dump_class_nlmsg, void *cookie); 433 int libbpf_nl_get_qdisc(int sock, unsigned int nl_pid, int ifindex, 434 libbpf_dump_nlmsg_t dump_qdisc_nlmsg, void *cookie); 435 int libbpf_nl_get_filter(int sock, unsigned int nl_pid, int ifindex, int handle, 436 libbpf_dump_nlmsg_t dump_filter_nlmsg, void *cookie); 437 438 struct bpf_prog_linfo; 439 struct bpf_prog_info; 440 441 LIBBPF_API void bpf_prog_linfo__free(struct bpf_prog_linfo *prog_linfo); 442 LIBBPF_API struct bpf_prog_linfo * 443 bpf_prog_linfo__new(const struct bpf_prog_info *info); 444 LIBBPF_API const struct bpf_line_info * 445 bpf_prog_linfo__lfind_addr_func(const struct bpf_prog_linfo *prog_linfo, 446 __u64 addr, __u32 func_idx, __u32 nr_skip); 447 LIBBPF_API const struct bpf_line_info * 448 bpf_prog_linfo__lfind(const struct bpf_prog_linfo *prog_linfo, 449 __u32 insn_off, __u32 nr_skip); 450 451 /* 452 * Probe for supported system features 453 * 454 * Note that running many of these probes in a short amount of time can cause 455 * the kernel to reach the maximal size of lockable memory allowed for the 456 * user, causing subsequent probes to fail. In this case, the caller may want 457 * to adjust that limit with setrlimit(). 458 */ 459 LIBBPF_API bool bpf_probe_prog_type(enum bpf_prog_type prog_type, 460 __u32 ifindex); 461 LIBBPF_API bool bpf_probe_map_type(enum bpf_map_type map_type, __u32 ifindex); 462 LIBBPF_API bool bpf_probe_helper(enum bpf_func_id id, 463 enum bpf_prog_type prog_type, __u32 ifindex); 464 465 /* 466 * Get bpf_prog_info in continuous memory 467 * 468 * struct bpf_prog_info has multiple arrays. The user has option to choose 469 * arrays to fetch from kernel. The following APIs provide an uniform way to 470 * fetch these data. All arrays in bpf_prog_info are stored in a single 471 * continuous memory region. This makes it easy to store the info in a 472 * file. 473 * 474 * Before writing bpf_prog_info_linear to files, it is necessary to 475 * translate pointers in bpf_prog_info to offsets. Helper functions 476 * bpf_program__bpil_addr_to_offs() and bpf_program__bpil_offs_to_addr() 477 * are introduced to switch between pointers and offsets. 478 * 479 * Examples: 480 * # To fetch map_ids and prog_tags: 481 * __u64 arrays = (1UL << BPF_PROG_INFO_MAP_IDS) | 482 * (1UL << BPF_PROG_INFO_PROG_TAGS); 483 * struct bpf_prog_info_linear *info_linear = 484 * bpf_program__get_prog_info_linear(fd, arrays); 485 * 486 * # To save data in file 487 * bpf_program__bpil_addr_to_offs(info_linear); 488 * write(f, info_linear, sizeof(*info_linear) + info_linear->data_len); 489 * 490 * # To read data from file 491 * read(f, info_linear, <proper_size>); 492 * bpf_program__bpil_offs_to_addr(info_linear); 493 */ 494 enum bpf_prog_info_array { 495 BPF_PROG_INFO_FIRST_ARRAY = 0, 496 BPF_PROG_INFO_JITED_INSNS = 0, 497 BPF_PROG_INFO_XLATED_INSNS, 498 BPF_PROG_INFO_MAP_IDS, 499 BPF_PROG_INFO_JITED_KSYMS, 500 BPF_PROG_INFO_JITED_FUNC_LENS, 501 BPF_PROG_INFO_FUNC_INFO, 502 BPF_PROG_INFO_LINE_INFO, 503 BPF_PROG_INFO_JITED_LINE_INFO, 504 BPF_PROG_INFO_PROG_TAGS, 505 BPF_PROG_INFO_LAST_ARRAY, 506 }; 507 508 struct bpf_prog_info_linear { 509 /* size of struct bpf_prog_info, when the tool is compiled */ 510 __u32 info_len; 511 /* total bytes allocated for data, round up to 8 bytes */ 512 __u32 data_len; 513 /* which arrays are included in data */ 514 __u64 arrays; 515 struct bpf_prog_info info; 516 __u8 data[]; 517 }; 518 519 LIBBPF_API struct bpf_prog_info_linear * 520 bpf_program__get_prog_info_linear(int fd, __u64 arrays); 521 522 LIBBPF_API void 523 bpf_program__bpil_addr_to_offs(struct bpf_prog_info_linear *info_linear); 524 525 LIBBPF_API void 526 bpf_program__bpil_offs_to_addr(struct bpf_prog_info_linear *info_linear); 527 528 /* 529 * A helper function to get the number of possible CPUs before looking up 530 * per-CPU maps. Negative errno is returned on failure. 531 * 532 * Example usage: 533 * 534 * int ncpus = libbpf_num_possible_cpus(); 535 * if (ncpus < 0) { 536 * // error handling 537 * } 538 * long values[ncpus]; 539 * bpf_map_lookup_elem(per_cpu_map_fd, key, values); 540 * 541 */ 542 LIBBPF_API int libbpf_num_possible_cpus(void); 543 544 #ifdef __cplusplus 545 } /* extern "C" */ 546 #endif 547 548 #endif /* __LIBBPF_LIBBPF_H */ 549