tools/lib/bpf/libbpf.h

   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, 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                      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 LIBBPF_API const char *bpf_object__name(const struct bpf_object *obj);
 136 LIBBPF_API unsigned int bpf_object__kversion(const struct bpf_object *obj);
 137
 138 struct btf;
 139 LIBBPF_API struct btf *bpf_object__btf(const struct bpf_object *obj);
 140 LIBBPF_API int bpf_object__btf_fd(const struct bpf_object *obj);
 141
 142 LIBBPF_API struct bpf_program *
 143 bpf_object__find_program_by_title(const struct bpf_object *obj,
 144                                   const char *title);
 145
 146 LIBBPF_API struct bpf_object *bpf_object__next(struct bpf_object *prev);
 147 #define bpf_object__for_each_safe(pos, tmp)                     \
 148         for ((pos) = bpf_object__next(NULL),            \
 149                 (tmp) = bpf_object__next(pos);          \
 150              (pos) != NULL;                             \
 151              (pos) = (tmp), (tmp) = bpf_object__next(tmp))
 152
 153 typedef void (*bpf_object_clear_priv_t)(struct bpf_object *, void *);
 154 LIBBPF_API int bpf_object__set_priv(struct bpf_object *obj, void *priv,
 155                                     bpf_object_clear_priv_t clear_priv);
 156 LIBBPF_API void *bpf_object__priv(const struct bpf_object *prog);
 157
 158 LIBBPF_API int
 159 libbpf_prog_type_by_name(const char *name, enum bpf_prog_type *prog_type,
 160                          enum bpf_attach_type *expected_attach_type);
 161 LIBBPF_API int libbpf_attach_type_by_name(const char *name,
 162                                           enum bpf_attach_type *attach_type);
 163 LIBBPF_API int libbpf_find_vmlinux_btf_id(const char *name,
 164                                           enum bpf_attach_type attach_type);
 165
 166 /* Accessors of bpf_program */
 167 struct bpf_program;
 168 LIBBPF_API struct bpf_program *bpf_program__next(struct bpf_program *prog,
 169                                                  const struct bpf_object *obj);
 170
 171 #define bpf_object__for_each_program(pos, obj)          \
 172         for ((pos) = bpf_program__next(NULL, (obj));    \
 173              (pos) != NULL;                             \
 174              (pos) = bpf_program__next((pos), (obj)))
 175
 176 LIBBPF_API struct bpf_program *bpf_program__prev(struct bpf_program *prog,
 177                                                  const struct bpf_object *obj);
 178
 179 typedef void (*bpf_program_clear_priv_t)(struct bpf_program *, void *);
 180
 181 LIBBPF_API int bpf_program__set_priv(struct bpf_program *prog, void *priv,
 182                                      bpf_program_clear_priv_t clear_priv);
 183
 184 LIBBPF_API void *bpf_program__priv(const struct bpf_program *prog);
 185 LIBBPF_API void bpf_program__set_ifindex(struct bpf_program *prog,
 186                                          __u32 ifindex);
 187
 188 LIBBPF_API const char *bpf_program__title(const struct bpf_program *prog,
 189                                           bool needs_copy);
 190
 191 /* returns program size in bytes */
 192 LIBBPF_API size_t bpf_program__size(const struct bpf_program *prog);
 193
 194 LIBBPF_API int bpf_program__load(struct bpf_program *prog, char *license,
 195                                  __u32 kern_version);
 196 LIBBPF_API int bpf_program__fd(const struct bpf_program *prog);
 197 LIBBPF_API int bpf_program__pin_instance(struct bpf_program *prog,
 198                                          const char *path,
 199                                          int instance);
 200 LIBBPF_API int bpf_program__unpin_instance(struct bpf_program *prog,
 201                                            const char *path,
 202                                            int instance);
 203 LIBBPF_API int bpf_program__pin(struct bpf_program *prog, const char *path);
 204 LIBBPF_API int bpf_program__unpin(struct bpf_program *prog, const char *path);
 205 LIBBPF_API void bpf_program__unload(struct bpf_program *prog);
 206
 207 struct bpf_link;
 208
 209 LIBBPF_API int bpf_link__destroy(struct bpf_link *link);
 210
 211 LIBBPF_API struct bpf_link *
 212 bpf_program__attach(struct bpf_program *prog);
 213 LIBBPF_API struct bpf_link *
 214 bpf_program__attach_perf_event(struct bpf_program *prog, int pfd);
 215 LIBBPF_API struct bpf_link *
 216 bpf_program__attach_kprobe(struct bpf_program *prog, bool retprobe,
 217                            const char *func_name);
 218 LIBBPF_API struct bpf_link *
 219 bpf_program__attach_uprobe(struct bpf_program *prog, bool retprobe,
 220                            pid_t pid, const char *binary_path,
 221                            size_t func_offset);
 222 LIBBPF_API struct bpf_link *
 223 bpf_program__attach_tracepoint(struct bpf_program *prog,
 224                                const char *tp_category,
 225                                const char *tp_name);
 226 LIBBPF_API struct bpf_link *
 227 bpf_program__attach_raw_tracepoint(struct bpf_program *prog,
 228                                    const char *tp_name);
 229
 230 LIBBPF_API struct bpf_link *
 231 bpf_program__attach_trace(struct bpf_program *prog);
 232 struct bpf_insn;
 233
 234 /*
 235  * Libbpf allows callers to adjust BPF programs before being loaded
 236  * into kernel. One program in an object file can be transformed into
 237  * multiple variants to be attached to different hooks.
 238  *
 239  * bpf_program_prep_t, bpf_program__set_prep and bpf_program__nth_fd
 240  * form an API for this purpose.
 241  *
 242  * - bpf_program_prep_t:
 243  *   Defines a 'preprocessor', which is a caller defined function
 244  *   passed to libbpf through bpf_program__set_prep(), and will be
 245  *   called before program is loaded. The processor should adjust
 246  *   the program one time for each instance according to the instance id
 247  *   passed to it.
 248  *
 249  * - bpf_program__set_prep:
 250  *   Attaches a preprocessor to a BPF program. The number of instances
 251  *   that should be created is also passed through this function.
 252  *
 253  * - bpf_program__nth_fd:
 254  *   After the program is loaded, get resulting FD of a given instance
 255  *   of the BPF program.
 256  *
 257  * If bpf_program__set_prep() is not used, the program would be loaded
 258  * without adjustment during bpf_object__load(). The program has only
 259  * one instance. In this case bpf_program__fd(prog) is equal to
 260  * bpf_program__nth_fd(prog, 0).
 261  */
 262
 263 struct bpf_prog_prep_result {
 264         /*
 265          * If not NULL, load new instruction array.
 266          * If set to NULL, don't load this instance.
 267          */
 268         struct bpf_insn *new_insn_ptr;
 269         int new_insn_cnt;
 270
 271         /* If not NULL, result FD is written to it. */
 272         int *pfd;
 273 };
 274
 275 /*
 276  * Parameters of bpf_program_prep_t:
 277  *  - prog:     The bpf_program being loaded.
 278  *  - n:        Index of instance being generated.
 279  *  - insns:    BPF instructions array.
 280  *  - insns_cnt:Number of instructions in insns.
 281  *  - res:      Output parameter, result of transformation.
 282  *
 283  * Return value:
 284  *  - Zero:     pre-processing success.
 285  *  - Non-zero: pre-processing error, stop loading.
 286  */
 287 typedef int (*bpf_program_prep_t)(struct bpf_program *prog, int n,
 288                                   struct bpf_insn *insns, int insns_cnt,
 289                                   struct bpf_prog_prep_result *res);
 290
 291 LIBBPF_API int bpf_program__set_prep(struct bpf_program *prog, int nr_instance,
 292                                      bpf_program_prep_t prep);
 293
 294 LIBBPF_API int bpf_program__nth_fd(const struct bpf_program *prog, int n);
 295
 296 /*
 297  * Adjust type of BPF program. Default is kprobe.
 298  */
 299 LIBBPF_API int bpf_program__set_socket_filter(struct bpf_program *prog);
 300 LIBBPF_API int bpf_program__set_tracepoint(struct bpf_program *prog);
 301 LIBBPF_API int bpf_program__set_raw_tracepoint(struct bpf_program *prog);
 302 LIBBPF_API int bpf_program__set_kprobe(struct bpf_program *prog);
 303 LIBBPF_API int bpf_program__set_sched_cls(struct bpf_program *prog);
 304 LIBBPF_API int bpf_program__set_sched_act(struct bpf_program *prog);
 305 LIBBPF_API int bpf_program__set_xdp(struct bpf_program *prog);
 306 LIBBPF_API int bpf_program__set_perf_event(struct bpf_program *prog);
 307 LIBBPF_API int bpf_program__set_tracing(struct bpf_program *prog);
 308
 309 LIBBPF_API enum bpf_prog_type bpf_program__get_type(struct bpf_program *prog);
 310 LIBBPF_API void bpf_program__set_type(struct bpf_program *prog,
 311                                       enum bpf_prog_type type);
 312
 313 LIBBPF_API enum bpf_attach_type
 314 bpf_program__get_expected_attach_type(struct bpf_program *prog);
 315 LIBBPF_API void
 316 bpf_program__set_expected_attach_type(struct bpf_program *prog,
 317                                       enum bpf_attach_type type);
 318
 319 LIBBPF_API bool bpf_program__is_socket_filter(const struct bpf_program *prog);
 320 LIBBPF_API bool bpf_program__is_tracepoint(const struct bpf_program *prog);
 321 LIBBPF_API bool bpf_program__is_raw_tracepoint(const struct bpf_program *prog);
 322 LIBBPF_API bool bpf_program__is_kprobe(const struct bpf_program *prog);
 323 LIBBPF_API bool bpf_program__is_sched_cls(const struct bpf_program *prog);
 324 LIBBPF_API bool bpf_program__is_sched_act(const struct bpf_program *prog);
 325 LIBBPF_API bool bpf_program__is_xdp(const struct bpf_program *prog);
 326 LIBBPF_API bool bpf_program__is_perf_event(const struct bpf_program *prog);
 327 LIBBPF_API bool bpf_program__is_tracing(const struct bpf_program *prog);
 328
 329 /*
 330  * No need for __attribute__((packed)), all members of 'bpf_map_def'
 331  * are all aligned.  In addition, using __attribute__((packed))
 332  * would trigger a -Wpacked warning message, and lead to an error
 333  * if -Werror is set.
 334  */
 335 struct bpf_map_def {
 336         unsigned int type;
 337         unsigned int key_size;
 338         unsigned int value_size;
 339         unsigned int max_entries;
 340         unsigned int map_flags;
 341 };
 342
 343 /*
 344  * The 'struct bpf_map' in include/linux/bpf.h is internal to the kernel,
 345  * so no need to worry about a name clash.
 346  */
 347 struct bpf_map;
 348 LIBBPF_API struct bpf_map *
 349 bpf_object__find_map_by_name(const struct bpf_object *obj, const char *name);
 350
 351 LIBBPF_API int
 352 bpf_object__find_map_fd_by_name(const struct bpf_object *obj, const char *name);
 353
 354 /*
 355  * Get bpf_map through the offset of corresponding struct bpf_map_def
 356  * in the BPF object file.
 357  */
 358 LIBBPF_API struct bpf_map *
 359 bpf_object__find_map_by_offset(struct bpf_object *obj, size_t offset);
 360
 361 LIBBPF_API struct bpf_map *
 362 bpf_map__next(const struct bpf_map *map, const struct bpf_object *obj);
 363 #define bpf_object__for_each_map(pos, obj)              \
 364         for ((pos) = bpf_map__next(NULL, (obj));        \
 365              (pos) != NULL;                             \
 366              (pos) = bpf_map__next((pos), (obj)))
 367 #define bpf_map__for_each bpf_object__for_each_map
 368
 369 LIBBPF_API struct bpf_map *
 370 bpf_map__prev(const struct bpf_map *map, const struct bpf_object *obj);
 371
 372 LIBBPF_API int bpf_map__fd(const struct bpf_map *map);
 373 LIBBPF_API const struct bpf_map_def *bpf_map__def(const struct bpf_map *map);
 374 LIBBPF_API const char *bpf_map__name(const struct bpf_map *map);
 375 LIBBPF_API __u32 bpf_map__btf_key_type_id(const struct bpf_map *map);
 376 LIBBPF_API __u32 bpf_map__btf_value_type_id(const struct bpf_map *map);
 377
 378 typedef void (*bpf_map_clear_priv_t)(struct bpf_map *, void *);
 379 LIBBPF_API int bpf_map__set_priv(struct bpf_map *map, void *priv,
 380                                  bpf_map_clear_priv_t clear_priv);
 381 LIBBPF_API void *bpf_map__priv(const struct bpf_map *map);
 382 LIBBPF_API int bpf_map__reuse_fd(struct bpf_map *map, int fd);
 383 LIBBPF_API int bpf_map__resize(struct bpf_map *map, __u32 max_entries);
 384 LIBBPF_API bool bpf_map__is_offload_neutral(const struct bpf_map *map);
 385 LIBBPF_API bool bpf_map__is_internal(const struct bpf_map *map);
 386 LIBBPF_API void bpf_map__set_ifindex(struct bpf_map *map, __u32 ifindex);
 387 LIBBPF_API int bpf_map__set_pin_path(struct bpf_map *map, const char *path);
 388 LIBBPF_API const char *bpf_map__get_pin_path(const struct bpf_map *map);
 389 LIBBPF_API bool bpf_map__is_pinned(const struct bpf_map *map);
 390 LIBBPF_API int bpf_map__pin(struct bpf_map *map, const char *path);
 391 LIBBPF_API int bpf_map__unpin(struct bpf_map *map, const char *path);
 392
 393 LIBBPF_API int bpf_map__set_inner_map_fd(struct bpf_map *map, int fd);
 394
 395 LIBBPF_API long libbpf_get_error(const void *ptr);
 396
 397 struct bpf_prog_load_attr {
 398         const char *file;
 399         enum bpf_prog_type prog_type;
 400         enum bpf_attach_type expected_attach_type;
 401         int ifindex;
 402         int log_level;
 403         int prog_flags;
 404 };
 405
 406 LIBBPF_API int bpf_prog_load_xattr(const struct bpf_prog_load_attr *attr,
 407                                    struct bpf_object **pobj, int *prog_fd);
 408 LIBBPF_API int bpf_prog_load(const char *file, enum bpf_prog_type type,
 409                              struct bpf_object **pobj, int *prog_fd);
 410
 411 struct xdp_link_info {
 412         __u32 prog_id;
 413         __u32 drv_prog_id;
 414         __u32 hw_prog_id;
 415         __u32 skb_prog_id;
 416         __u8 attach_mode;
 417 };
 418
 419 LIBBPF_API int bpf_set_link_xdp_fd(int ifindex, int fd, __u32 flags);
 420 LIBBPF_API int bpf_get_link_xdp_id(int ifindex, __u32 *prog_id, __u32 flags);
 421 LIBBPF_API int bpf_get_link_xdp_info(int ifindex, struct xdp_link_info *info,
 422                                      size_t info_size, __u32 flags);
 423
 424 struct perf_buffer;
 425
 426 typedef void (*perf_buffer_sample_fn)(void *ctx, int cpu,
 427                                       void *data, __u32 size);
 428 typedef void (*perf_buffer_lost_fn)(void *ctx, int cpu, __u64 cnt);
 429
 430 /* common use perf buffer options */
 431 struct perf_buffer_opts {
 432         /* if specified, sample_cb is called for each sample */
 433         perf_buffer_sample_fn sample_cb;
 434         /* if specified, lost_cb is called for each batch of lost samples */
 435         perf_buffer_lost_fn lost_cb;
 436         /* ctx is provided to sample_cb and lost_cb */
 437         void *ctx;
 438 };
 439
 440 LIBBPF_API struct perf_buffer *
 441 perf_buffer__new(int map_fd, size_t page_cnt,
 442                  const struct perf_buffer_opts *opts);
 443
 444 enum bpf_perf_event_ret {
 445         LIBBPF_PERF_EVENT_DONE  = 0,
 446         LIBBPF_PERF_EVENT_ERROR = -1,
 447         LIBBPF_PERF_EVENT_CONT  = -2,
 448 };
 449
 450 struct perf_event_header;
 451
 452 typedef enum bpf_perf_event_ret
 453 (*perf_buffer_event_fn)(void *ctx, int cpu, struct perf_event_header *event);
 454
 455 /* raw perf buffer options, giving most power and control */
 456 struct perf_buffer_raw_opts {
 457         /* perf event attrs passed directly into perf_event_open() */
 458         struct perf_event_attr *attr;
 459         /* raw event callback */
 460         perf_buffer_event_fn event_cb;
 461         /* ctx is provided to event_cb */
 462         void *ctx;
 463         /* if cpu_cnt == 0, open all on all possible CPUs (up to the number of
 464          * max_entries of given PERF_EVENT_ARRAY map)
 465          */
 466         int cpu_cnt;
 467         /* if cpu_cnt > 0, cpus is an array of CPUs to open ring buffers on */
 468         int *cpus;
 469         /* if cpu_cnt > 0, map_keys specify map keys to set per-CPU FDs for */
 470         int *map_keys;
 471 };
 472
 473 LIBBPF_API struct perf_buffer *
 474 perf_buffer__new_raw(int map_fd, size_t page_cnt,
 475                      const struct perf_buffer_raw_opts *opts);
 476
 477 LIBBPF_API void perf_buffer__free(struct perf_buffer *pb);
 478 LIBBPF_API int perf_buffer__poll(struct perf_buffer *pb, int timeout_ms);
 479
 480 typedef enum bpf_perf_event_ret
 481         (*bpf_perf_event_print_t)(struct perf_event_header *hdr,
 482                                   void *private_data);
 483 LIBBPF_API enum bpf_perf_event_ret
 484 bpf_perf_event_read_simple(void *mmap_mem, size_t mmap_size, size_t page_size,
 485                            void **copy_mem, size_t *copy_size,
 486                            bpf_perf_event_print_t fn, void *private_data);
 487
 488 struct bpf_prog_linfo;
 489 struct bpf_prog_info;
 490
 491 LIBBPF_API void bpf_prog_linfo__free(struct bpf_prog_linfo *prog_linfo);
 492 LIBBPF_API struct bpf_prog_linfo *
 493 bpf_prog_linfo__new(const struct bpf_prog_info *info);
 494 LIBBPF_API const struct bpf_line_info *
 495 bpf_prog_linfo__lfind_addr_func(const struct bpf_prog_linfo *prog_linfo,
 496                                 __u64 addr, __u32 func_idx, __u32 nr_skip);
 497 LIBBPF_API const struct bpf_line_info *
 498 bpf_prog_linfo__lfind(const struct bpf_prog_linfo *prog_linfo,
 499                       __u32 insn_off, __u32 nr_skip);
 500
 501 /*
 502  * Probe for supported system features
 503  *
 504  * Note that running many of these probes in a short amount of time can cause
 505  * the kernel to reach the maximal size of lockable memory allowed for the
 506  * user, causing subsequent probes to fail. In this case, the caller may want
 507  * to adjust that limit with setrlimit().
 508  */
 509 LIBBPF_API bool bpf_probe_prog_type(enum bpf_prog_type prog_type,
 510                                     __u32 ifindex);
 511 LIBBPF_API bool bpf_probe_map_type(enum bpf_map_type map_type, __u32 ifindex);
 512 LIBBPF_API bool bpf_probe_helper(enum bpf_func_id id,
 513                                  enum bpf_prog_type prog_type, __u32 ifindex);
 514
 515 /*
 516  * Get bpf_prog_info in continuous memory
 517  *
 518  * struct bpf_prog_info has multiple arrays. The user has option to choose
 519  * arrays to fetch from kernel. The following APIs provide an uniform way to
 520  * fetch these data. All arrays in bpf_prog_info are stored in a single
 521  * continuous memory region. This makes it easy to store the info in a
 522  * file.
 523  *
 524  * Before writing bpf_prog_info_linear to files, it is necessary to
 525  * translate pointers in bpf_prog_info to offsets. Helper functions
 526  * bpf_program__bpil_addr_to_offs() and bpf_program__bpil_offs_to_addr()
 527  * are introduced to switch between pointers and offsets.
 528  *
 529  * Examples:
 530  *   # To fetch map_ids and prog_tags:
 531  *   __u64 arrays = (1UL << BPF_PROG_INFO_MAP_IDS) |
 532  *           (1UL << BPF_PROG_INFO_PROG_TAGS);
 533  *   struct bpf_prog_info_linear *info_linear =
 534  *           bpf_program__get_prog_info_linear(fd, arrays);
 535  *
 536  *   # To save data in file
 537  *   bpf_program__bpil_addr_to_offs(info_linear);
 538  *   write(f, info_linear, sizeof(*info_linear) + info_linear->data_len);
 539  *
 540  *   # To read data from file
 541  *   read(f, info_linear, <proper_size>);
 542  *   bpf_program__bpil_offs_to_addr(info_linear);
 543  */
 544 enum bpf_prog_info_array {
 545         BPF_PROG_INFO_FIRST_ARRAY = 0,
 546         BPF_PROG_INFO_JITED_INSNS = 0,
 547         BPF_PROG_INFO_XLATED_INSNS,
 548         BPF_PROG_INFO_MAP_IDS,
 549         BPF_PROG_INFO_JITED_KSYMS,
 550         BPF_PROG_INFO_JITED_FUNC_LENS,
 551         BPF_PROG_INFO_FUNC_INFO,
 552         BPF_PROG_INFO_LINE_INFO,
 553         BPF_PROG_INFO_JITED_LINE_INFO,
 554         BPF_PROG_INFO_PROG_TAGS,
 555         BPF_PROG_INFO_LAST_ARRAY,
 556 };
 557
 558 struct bpf_prog_info_linear {
 559         /* size of struct bpf_prog_info, when the tool is compiled */
 560         __u32                   info_len;
 561         /* total bytes allocated for data, round up to 8 bytes */
 562         __u32                   data_len;
 563         /* which arrays are included in data */
 564         __u64                   arrays;
 565         struct bpf_prog_info    info;
 566         __u8                    data[];
 567 };
 568
 569 LIBBPF_API struct bpf_prog_info_linear *
 570 bpf_program__get_prog_info_linear(int fd, __u64 arrays);
 571
 572 LIBBPF_API void
 573 bpf_program__bpil_addr_to_offs(struct bpf_prog_info_linear *info_linear);
 574
 575 LIBBPF_API void
 576 bpf_program__bpil_offs_to_addr(struct bpf_prog_info_linear *info_linear);
 577
 578 /*
 579  * A helper function to get the number of possible CPUs before looking up
 580  * per-CPU maps. Negative errno is returned on failure.
 581  *
 582  * Example usage:
 583  *
 584  *     int ncpus = libbpf_num_possible_cpus();
 585  *     if (ncpus < 0) {
 586  *          // error handling
 587  *     }
 588  *     long values[ncpus];
 589  *     bpf_map_lookup_elem(per_cpu_map_fd, key, values);
 590  *
 591  */
 592 LIBBPF_API int libbpf_num_possible_cpus(void);
 593
 594 struct bpf_embed_data {
 595         void *data;
 596         size_t size;
 597 };
 598
 599 #define BPF_EMBED_OBJ_DECLARE(NAME)                                     \
 600 extern struct bpf_embed_data NAME##_embed;                              \
 601 extern char NAME##_data[];                                              \
 602 extern char NAME##_data_end[];
 603
 604 #define __BPF_EMBED_OBJ(NAME, PATH, SZ, ASM_TYPE)                       \
 605 asm (                                                                   \
 606 "       .pushsection \".rodata\", \"a\", @progbits              \n"     \
 607 "       .global "#NAME"_data                                    \n"     \
 608 #NAME"_data:                                                    \n"     \
 609 "       .incbin \"" PATH "\"                                    \n"     \
 610 "       .global "#NAME"_data_end                                \n"     \
 611 #NAME"_data_end:                                                \n"     \
 612 "       .global "#NAME"_embed                                   \n"     \
 613 "       .type "#NAME"_embed, @object                            \n"     \
 614 "       .size "#NAME"_size, "#SZ"                               \n"     \
 615 "       .align 8,                                               \n"     \
 616 #NAME"_embed:                                                   \n"     \
 617 "       "ASM_TYPE" "#NAME"_data                                 \n"     \
 618 "       "ASM_TYPE" "#NAME"_data_end - "#NAME"_data              \n"     \
 619 "       .popsection                                             \n"     \
 620 );                                                                      \
 621 BPF_EMBED_OBJ_DECLARE(NAME)
 622
 623 #if __SIZEOF_POINTER__ == 4
 624 #define BPF_EMBED_OBJ(NAME, PATH) __BPF_EMBED_OBJ(NAME, PATH, 8, ".long")
 625 #else
 626 #define BPF_EMBED_OBJ(NAME, PATH) __BPF_EMBED_OBJ(NAME, PATH, 16, ".quad")
 627 #endif
 628
 629 #ifdef __cplusplus
 630 } /* extern "C" */
 631 #endif
 632
 633 #endif /* __LIBBPF_LIBBPF_H */