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