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