1 /* SPDX-License-Identifier: (LGPL-2.1 OR BSD-2-Clause) */ 2 3 /* 4 * Common eBPF ELF object loading operations. 5 * 6 * Copyright (C) 2013-2015 Alexei Starovoitov <ast@kernel.org> 7 * Copyright (C) 2015 Wang Nan <wangnan0@huawei.com> 8 * Copyright (C) 2015 Huawei Inc. 9 */ 10 #ifndef __LIBBPF_LIBBPF_H 11 #define __LIBBPF_LIBBPF_H 12 13 #include <stdarg.h> 14 #include <stdio.h> 15 #include <stdint.h> 16 #include <stdbool.h> 17 #include <sys/types.h> // for size_t 18 #include <linux/bpf.h> 19 20 #include "libbpf_common.h" 21 #include "libbpf_legacy.h" 22 23 #ifdef __cplusplus 24 extern "C" { 25 #endif 26 27 LIBBPF_API __u32 libbpf_major_version(void); 28 LIBBPF_API __u32 libbpf_minor_version(void); 29 LIBBPF_API const char *libbpf_version_string(void); 30 31 enum libbpf_errno { 32 __LIBBPF_ERRNO__START = 4000, 33 34 /* Something wrong in libelf */ 35 LIBBPF_ERRNO__LIBELF = __LIBBPF_ERRNO__START, 36 LIBBPF_ERRNO__FORMAT, /* BPF object format invalid */ 37 LIBBPF_ERRNO__KVERSION, /* Incorrect or no 'version' section */ 38 LIBBPF_ERRNO__ENDIAN, /* Endian mismatch */ 39 LIBBPF_ERRNO__INTERNAL, /* Internal error in libbpf */ 40 LIBBPF_ERRNO__RELOC, /* Relocation failed */ 41 LIBBPF_ERRNO__LOAD, /* Load program failure for unknown reason */ 42 LIBBPF_ERRNO__VERIFY, /* Kernel verifier blocks program loading */ 43 LIBBPF_ERRNO__PROG2BIG, /* Program too big */ 44 LIBBPF_ERRNO__KVER, /* Incorrect kernel version */ 45 LIBBPF_ERRNO__PROGTYPE, /* Kernel doesn't support this program type */ 46 LIBBPF_ERRNO__WRNGPID, /* Wrong pid in netlink message */ 47 LIBBPF_ERRNO__INVSEQ, /* Invalid netlink sequence */ 48 LIBBPF_ERRNO__NLPARSE, /* netlink parsing error */ 49 __LIBBPF_ERRNO__END, 50 }; 51 52 LIBBPF_API int libbpf_strerror(int err, char *buf, size_t size); 53 54 enum libbpf_print_level { 55 LIBBPF_WARN, 56 LIBBPF_INFO, 57 LIBBPF_DEBUG, 58 }; 59 60 typedef int (*libbpf_print_fn_t)(enum libbpf_print_level level, 61 const char *, va_list ap); 62 63 LIBBPF_API libbpf_print_fn_t libbpf_set_print(libbpf_print_fn_t fn); 64 65 /* Hide internal to user */ 66 struct bpf_object; 67 68 struct bpf_object_open_attr { 69 const char *file; 70 enum bpf_prog_type prog_type; 71 }; 72 73 struct bpf_object_open_opts { 74 /* size of this struct, for forward/backward compatiblity */ 75 size_t sz; 76 /* object name override, if provided: 77 * - for object open from file, this will override setting object 78 * name from file path's base name; 79 * - for object open from memory buffer, this will specify an object 80 * name and will override default "<addr>-<buf-size>" name; 81 */ 82 const char *object_name; 83 /* parse map definitions non-strictly, allowing extra attributes/data */ 84 bool relaxed_maps; 85 /* DEPRECATED: handle CO-RE relocations non-strictly, allowing failures. 86 * Value is ignored. Relocations always are processed non-strictly. 87 * Non-relocatable instructions are replaced with invalid ones to 88 * prevent accidental errors. 89 * */ 90 LIBBPF_DEPRECATED_SINCE(0, 6, "field has no effect") 91 bool relaxed_core_relocs; 92 /* maps that set the 'pinning' attribute in their definition will have 93 * their pin_path attribute set to a file in this directory, and be 94 * auto-pinned to that path on load; defaults to "/sys/fs/bpf". 95 */ 96 const char *pin_root_path; 97 98 LIBBPF_DEPRECATED_SINCE(0, 7, "use bpf_program__set_attach_target() on each individual bpf_program") 99 __u32 attach_prog_fd; 100 /* Additional kernel config content that augments and overrides 101 * system Kconfig for CONFIG_xxx externs. 102 */ 103 const char *kconfig; 104 /* Path to the custom BTF to be used for BPF CO-RE relocations. 105 * This custom BTF completely replaces the use of vmlinux BTF 106 * for the purpose of CO-RE relocations. 107 * NOTE: any other BPF feature (e.g., fentry/fexit programs, 108 * struct_ops, etc) will need actual kernel BTF at /sys/kernel/btf/vmlinux. 109 */ 110 const char *btf_custom_path; 111 /* Pointer to a buffer for storing kernel logs for applicable BPF 112 * commands. Valid kernel_log_size has to be specified as well and are 113 * passed-through to bpf() syscall. Keep in mind that kernel might 114 * fail operation with -ENOSPC error if provided buffer is too small 115 * to contain entire log output. 116 * See the comment below for kernel_log_level for interaction between 117 * log_buf and log_level settings. 118 * 119 * If specified, this log buffer will be passed for: 120 * - each BPF progral load (BPF_PROG_LOAD) attempt, unless overriden 121 * with bpf_program__set_log() on per-program level, to get 122 * BPF verifier log output. 123 * - during BPF object's BTF load into kernel (BPF_BTF_LOAD) to get 124 * BTF sanity checking log. 125 * 126 * Each BPF command (BPF_BTF_LOAD or BPF_PROG_LOAD) will overwrite 127 * previous contents, so if you need more fine-grained control, set 128 * per-program buffer with bpf_program__set_log_buf() to preserve each 129 * individual program's verification log. Keep using kernel_log_buf 130 * for BTF verification log, if necessary. 131 */ 132 char *kernel_log_buf; 133 size_t kernel_log_size; 134 /* 135 * Log level can be set independently from log buffer. Log_level=0 136 * means that libbpf will attempt loading BTF or program without any 137 * logging requested, but will retry with either its own or custom log 138 * buffer, if provided, and log_level=1 on any error. 139 * And vice versa, setting log_level>0 will request BTF or prog 140 * loading with verbose log from the first attempt (and as such also 141 * for successfully loaded BTF or program), and the actual log buffer 142 * could be either libbpf's own auto-allocated log buffer, if 143 * kernel_log_buffer is NULL, or user-provided custom kernel_log_buf. 144 * If user didn't provide custom log buffer, libbpf will emit captured 145 * logs through its print callback. 146 */ 147 __u32 kernel_log_level; 148 149 size_t :0; 150 }; 151 #define bpf_object_open_opts__last_field kernel_log_level 152 153 LIBBPF_API struct bpf_object *bpf_object__open(const char *path); 154 155 /** 156 * @brief **bpf_object__open_file()** creates a bpf_object by opening 157 * the BPF ELF object file pointed to by the passed path and loading it 158 * into memory. 159 * @param path BPF object file path 160 * @param opts options for how to load the bpf object, this parameter is 161 * optional and can be set to NULL 162 * @return pointer to the new bpf_object; or NULL is returned on error, 163 * error code is stored in errno 164 */ 165 LIBBPF_API struct bpf_object * 166 bpf_object__open_file(const char *path, const struct bpf_object_open_opts *opts); 167 168 /** 169 * @brief **bpf_object__open_mem()** creates a bpf_object by reading 170 * the BPF objects raw bytes from a memory buffer containing a valid 171 * BPF ELF object file. 172 * @param obj_buf pointer to the buffer containing ELF file bytes 173 * @param obj_buf_sz number of bytes in the buffer 174 * @param opts options for how to load the bpf object 175 * @return pointer to the new bpf_object; or NULL is returned on error, 176 * error code is stored in errno 177 */ 178 LIBBPF_API struct bpf_object * 179 bpf_object__open_mem(const void *obj_buf, size_t obj_buf_sz, 180 const struct bpf_object_open_opts *opts); 181 182 /* deprecated bpf_object__open variants */ 183 LIBBPF_DEPRECATED_SINCE(0, 8, "use bpf_object__open_mem() instead") 184 LIBBPF_API struct bpf_object * 185 bpf_object__open_buffer(const void *obj_buf, size_t obj_buf_sz, 186 const char *name); 187 LIBBPF_DEPRECATED_SINCE(0, 7, "use bpf_object__open_file() instead") 188 LIBBPF_API struct bpf_object * 189 bpf_object__open_xattr(struct bpf_object_open_attr *attr); 190 191 enum libbpf_pin_type { 192 LIBBPF_PIN_NONE, 193 /* PIN_BY_NAME: pin maps by name (in /sys/fs/bpf by default) */ 194 LIBBPF_PIN_BY_NAME, 195 }; 196 197 /* pin_maps and unpin_maps can both be called with a NULL path, in which case 198 * they will use the pin_path attribute of each map (and ignore all maps that 199 * don't have a pin_path set). 200 */ 201 LIBBPF_API int bpf_object__pin_maps(struct bpf_object *obj, const char *path); 202 LIBBPF_API int bpf_object__unpin_maps(struct bpf_object *obj, 203 const char *path); 204 LIBBPF_API int bpf_object__pin_programs(struct bpf_object *obj, 205 const char *path); 206 LIBBPF_API int bpf_object__unpin_programs(struct bpf_object *obj, 207 const char *path); 208 LIBBPF_API int bpf_object__pin(struct bpf_object *object, const char *path); 209 LIBBPF_API void bpf_object__close(struct bpf_object *object); 210 211 struct bpf_object_load_attr { 212 struct bpf_object *obj; 213 int log_level; 214 const char *target_btf_path; 215 }; 216 217 /* Load/unload object into/from kernel */ 218 LIBBPF_API int bpf_object__load(struct bpf_object *obj); 219 LIBBPF_DEPRECATED_SINCE(0, 8, "use bpf_object__load() instead") 220 LIBBPF_API int bpf_object__load_xattr(struct bpf_object_load_attr *attr); 221 LIBBPF_DEPRECATED_SINCE(0, 6, "bpf_object__unload() is deprecated, use bpf_object__close() instead") 222 LIBBPF_API int bpf_object__unload(struct bpf_object *obj); 223 224 LIBBPF_API const char *bpf_object__name(const struct bpf_object *obj); 225 LIBBPF_API unsigned int bpf_object__kversion(const struct bpf_object *obj); 226 LIBBPF_API int bpf_object__set_kversion(struct bpf_object *obj, __u32 kern_version); 227 228 struct btf; 229 LIBBPF_API struct btf *bpf_object__btf(const struct bpf_object *obj); 230 LIBBPF_API int bpf_object__btf_fd(const struct bpf_object *obj); 231 232 LIBBPF_DEPRECATED_SINCE(0, 7, "use bpf_object__find_program_by_name() instead") 233 LIBBPF_API struct bpf_program * 234 bpf_object__find_program_by_title(const struct bpf_object *obj, 235 const char *title); 236 LIBBPF_API struct bpf_program * 237 bpf_object__find_program_by_name(const struct bpf_object *obj, 238 const char *name); 239 240 LIBBPF_API LIBBPF_DEPRECATED_SINCE(0, 7, "track bpf_objects in application code instead") 241 struct bpf_object *bpf_object__next(struct bpf_object *prev); 242 #define bpf_object__for_each_safe(pos, tmp) \ 243 for ((pos) = bpf_object__next(NULL), \ 244 (tmp) = bpf_object__next(pos); \ 245 (pos) != NULL; \ 246 (pos) = (tmp), (tmp) = bpf_object__next(tmp)) 247 248 typedef void (*bpf_object_clear_priv_t)(struct bpf_object *, void *); 249 LIBBPF_DEPRECATED_SINCE(0, 7, "storage via set_priv/priv is deprecated") 250 LIBBPF_API int bpf_object__set_priv(struct bpf_object *obj, void *priv, 251 bpf_object_clear_priv_t clear_priv); 252 LIBBPF_DEPRECATED_SINCE(0, 7, "storage via set_priv/priv is deprecated") 253 LIBBPF_API void *bpf_object__priv(const struct bpf_object *prog); 254 255 LIBBPF_API int 256 libbpf_prog_type_by_name(const char *name, enum bpf_prog_type *prog_type, 257 enum bpf_attach_type *expected_attach_type); 258 LIBBPF_API int libbpf_attach_type_by_name(const char *name, 259 enum bpf_attach_type *attach_type); 260 LIBBPF_API int libbpf_find_vmlinux_btf_id(const char *name, 261 enum bpf_attach_type attach_type); 262 263 /* Accessors of bpf_program */ 264 struct bpf_program; 265 LIBBPF_API LIBBPF_DEPRECATED_SINCE(0, 7, "use bpf_object__next_program() instead") 266 struct bpf_program *bpf_program__next(struct bpf_program *prog, 267 const struct bpf_object *obj); 268 LIBBPF_API struct bpf_program * 269 bpf_object__next_program(const struct bpf_object *obj, struct bpf_program *prog); 270 271 #define bpf_object__for_each_program(pos, obj) \ 272 for ((pos) = bpf_object__next_program((obj), NULL); \ 273 (pos) != NULL; \ 274 (pos) = bpf_object__next_program((obj), (pos))) 275 276 LIBBPF_API LIBBPF_DEPRECATED_SINCE(0, 7, "use bpf_object__prev_program() instead") 277 struct bpf_program *bpf_program__prev(struct bpf_program *prog, 278 const struct bpf_object *obj); 279 LIBBPF_API struct bpf_program * 280 bpf_object__prev_program(const struct bpf_object *obj, struct bpf_program *prog); 281 282 typedef void (*bpf_program_clear_priv_t)(struct bpf_program *, void *); 283 284 LIBBPF_DEPRECATED_SINCE(0, 7, "storage via set_priv/priv is deprecated") 285 LIBBPF_API int bpf_program__set_priv(struct bpf_program *prog, void *priv, 286 bpf_program_clear_priv_t clear_priv); 287 LIBBPF_DEPRECATED_SINCE(0, 7, "storage via set_priv/priv is deprecated") 288 LIBBPF_API void *bpf_program__priv(const struct bpf_program *prog); 289 LIBBPF_API void bpf_program__set_ifindex(struct bpf_program *prog, 290 __u32 ifindex); 291 292 LIBBPF_API const char *bpf_program__name(const struct bpf_program *prog); 293 LIBBPF_API const char *bpf_program__section_name(const struct bpf_program *prog); 294 LIBBPF_API LIBBPF_DEPRECATED("BPF program title is confusing term; please use bpf_program__section_name() instead") 295 const char *bpf_program__title(const struct bpf_program *prog, bool needs_copy); 296 LIBBPF_API bool bpf_program__autoload(const struct bpf_program *prog); 297 LIBBPF_API int bpf_program__set_autoload(struct bpf_program *prog, bool autoload); 298 299 /* returns program size in bytes */ 300 LIBBPF_DEPRECATED_SINCE(0, 7, "use bpf_program__insn_cnt() instead") 301 LIBBPF_API size_t bpf_program__size(const struct bpf_program *prog); 302 303 struct bpf_insn; 304 305 /** 306 * @brief **bpf_program__insns()** gives read-only access to BPF program's 307 * underlying BPF instructions. 308 * @param prog BPF program for which to return instructions 309 * @return a pointer to an array of BPF instructions that belong to the 310 * specified BPF program 311 * 312 * Returned pointer is always valid and not NULL. Number of `struct bpf_insn` 313 * pointed to can be fetched using **bpf_program__insn_cnt()** API. 314 * 315 * Keep in mind, libbpf can modify and append/delete BPF program's 316 * instructions as it processes BPF object file and prepares everything for 317 * uploading into the kernel. So depending on the point in BPF object 318 * lifetime, **bpf_program__insns()** can return different sets of 319 * instructions. As an example, during BPF object load phase BPF program 320 * instructions will be CO-RE-relocated, BPF subprograms instructions will be 321 * appended, ldimm64 instructions will have FDs embedded, etc. So instructions 322 * returned before **bpf_object__load()** and after it might be quite 323 * different. 324 */ 325 LIBBPF_API const struct bpf_insn *bpf_program__insns(const struct bpf_program *prog); 326 /** 327 * @brief **bpf_program__insn_cnt()** returns number of `struct bpf_insn`'s 328 * that form specified BPF program. 329 * @param prog BPF program for which to return number of BPF instructions 330 * 331 * See **bpf_program__insns()** documentation for notes on how libbpf can 332 * change instructions and their count during different phases of 333 * **bpf_object** lifetime. 334 */ 335 LIBBPF_API size_t bpf_program__insn_cnt(const struct bpf_program *prog); 336 337 LIBBPF_DEPRECATED_SINCE(0, 6, "use bpf_object__load() instead") 338 LIBBPF_API int bpf_program__load(struct bpf_program *prog, const char *license, __u32 kern_version); 339 LIBBPF_API int bpf_program__fd(const struct bpf_program *prog); 340 LIBBPF_DEPRECATED_SINCE(0, 7, "multi-instance bpf_program support is deprecated") 341 LIBBPF_API int bpf_program__pin_instance(struct bpf_program *prog, 342 const char *path, 343 int instance); 344 LIBBPF_DEPRECATED_SINCE(0, 7, "multi-instance bpf_program support is deprecated") 345 LIBBPF_API int bpf_program__unpin_instance(struct bpf_program *prog, 346 const char *path, 347 int instance); 348 349 /** 350 * @brief **bpf_program__pin()** pins the BPF program to a file 351 * in the BPF FS specified by a path. This increments the programs 352 * reference count, allowing it to stay loaded after the process 353 * which loaded it has exited. 354 * 355 * @param prog BPF program to pin, must already be loaded 356 * @param path file path in a BPF file system 357 * @return 0, on success; negative error code, otherwise 358 */ 359 LIBBPF_API int bpf_program__pin(struct bpf_program *prog, const char *path); 360 361 /** 362 * @brief **bpf_program__unpin()** unpins the BPF program from a file 363 * in the BPFFS specified by a path. This decrements the programs 364 * reference count. 365 * 366 * The file pinning the BPF program can also be unlinked by a different 367 * process in which case this function will return an error. 368 * 369 * @param prog BPF program to unpin 370 * @param path file path to the pin in a BPF file system 371 * @return 0, on success; negative error code, otherwise 372 */ 373 LIBBPF_API int bpf_program__unpin(struct bpf_program *prog, const char *path); 374 LIBBPF_API void bpf_program__unload(struct bpf_program *prog); 375 376 struct bpf_link; 377 378 LIBBPF_API struct bpf_link *bpf_link__open(const char *path); 379 LIBBPF_API int bpf_link__fd(const struct bpf_link *link); 380 LIBBPF_API const char *bpf_link__pin_path(const struct bpf_link *link); 381 LIBBPF_API int bpf_link__pin(struct bpf_link *link, const char *path); 382 LIBBPF_API int bpf_link__unpin(struct bpf_link *link); 383 LIBBPF_API int bpf_link__update_program(struct bpf_link *link, 384 struct bpf_program *prog); 385 LIBBPF_API void bpf_link__disconnect(struct bpf_link *link); 386 LIBBPF_API int bpf_link__detach(struct bpf_link *link); 387 LIBBPF_API int bpf_link__destroy(struct bpf_link *link); 388 389 LIBBPF_API struct bpf_link * 390 bpf_program__attach(const struct bpf_program *prog); 391 392 struct bpf_perf_event_opts { 393 /* size of this struct, for forward/backward compatiblity */ 394 size_t sz; 395 /* custom user-provided value fetchable through bpf_get_attach_cookie() */ 396 __u64 bpf_cookie; 397 }; 398 #define bpf_perf_event_opts__last_field bpf_cookie 399 400 LIBBPF_API struct bpf_link * 401 bpf_program__attach_perf_event(const struct bpf_program *prog, int pfd); 402 403 LIBBPF_API struct bpf_link * 404 bpf_program__attach_perf_event_opts(const struct bpf_program *prog, int pfd, 405 const struct bpf_perf_event_opts *opts); 406 407 struct bpf_kprobe_opts { 408 /* size of this struct, for forward/backward compatiblity */ 409 size_t sz; 410 /* custom user-provided value fetchable through bpf_get_attach_cookie() */ 411 __u64 bpf_cookie; 412 /* function's offset to install kprobe to */ 413 size_t offset; 414 /* kprobe is return probe */ 415 bool retprobe; 416 size_t :0; 417 }; 418 #define bpf_kprobe_opts__last_field retprobe 419 420 LIBBPF_API struct bpf_link * 421 bpf_program__attach_kprobe(const struct bpf_program *prog, bool retprobe, 422 const char *func_name); 423 LIBBPF_API struct bpf_link * 424 bpf_program__attach_kprobe_opts(const struct bpf_program *prog, 425 const char *func_name, 426 const struct bpf_kprobe_opts *opts); 427 428 struct bpf_kprobe_multi_opts { 429 /* size of this struct, for forward/backward compatibility */ 430 size_t sz; 431 /* array of function symbols to attach */ 432 const char **syms; 433 /* array of function addresses to attach */ 434 const unsigned long *addrs; 435 /* array of user-provided values fetchable through bpf_get_attach_cookie */ 436 const __u64 *cookies; 437 /* number of elements in syms/addrs/cookies arrays */ 438 size_t cnt; 439 /* create return kprobes */ 440 bool retprobe; 441 size_t :0; 442 }; 443 444 #define bpf_kprobe_multi_opts__last_field retprobe 445 446 LIBBPF_API struct bpf_link * 447 bpf_program__attach_kprobe_multi_opts(const struct bpf_program *prog, 448 const char *pattern, 449 const struct bpf_kprobe_multi_opts *opts); 450 451 struct bpf_uprobe_opts { 452 /* size of this struct, for forward/backward compatiblity */ 453 size_t sz; 454 /* offset of kernel reference counted USDT semaphore, added in 455 * a6ca88b241d5 ("trace_uprobe: support reference counter in fd-based uprobe") 456 */ 457 size_t ref_ctr_offset; 458 /* custom user-provided value fetchable through bpf_get_attach_cookie() */ 459 __u64 bpf_cookie; 460 /* uprobe is return probe, invoked at function return time */ 461 bool retprobe; 462 /* Function name to attach to. Could be an unqualified ("abc") or library-qualified 463 * "abc@LIBXYZ" name. To specify function entry, func_name should be set while 464 * func_offset argument to bpf_prog__attach_uprobe_opts() should be 0. To trace an 465 * offset within a function, specify func_name and use func_offset argument to specify 466 * offset within the function. Shared library functions must specify the shared library 467 * binary_path. 468 */ 469 const char *func_name; 470 size_t :0; 471 }; 472 #define bpf_uprobe_opts__last_field func_name 473 474 /** 475 * @brief **bpf_program__attach_uprobe()** attaches a BPF program 476 * to the userspace function which is found by binary path and 477 * offset. You can optionally specify a particular proccess to attach 478 * to. You can also optionally attach the program to the function 479 * exit instead of entry. 480 * 481 * @param prog BPF program to attach 482 * @param retprobe Attach to function exit 483 * @param pid Process ID to attach the uprobe to, 0 for self (own process), 484 * -1 for all processes 485 * @param binary_path Path to binary that contains the function symbol 486 * @param func_offset Offset within the binary of the function symbol 487 * @return Reference to the newly created BPF link; or NULL is returned on error, 488 * error code is stored in errno 489 */ 490 LIBBPF_API struct bpf_link * 491 bpf_program__attach_uprobe(const struct bpf_program *prog, bool retprobe, 492 pid_t pid, const char *binary_path, 493 size_t func_offset); 494 495 /** 496 * @brief **bpf_program__attach_uprobe_opts()** is just like 497 * bpf_program__attach_uprobe() except with a options struct 498 * for various configurations. 499 * 500 * @param prog BPF program to attach 501 * @param pid Process ID to attach the uprobe to, 0 for self (own process), 502 * -1 for all processes 503 * @param binary_path Path to binary that contains the function symbol 504 * @param func_offset Offset within the binary of the function symbol 505 * @param opts Options for altering program attachment 506 * @return Reference to the newly created BPF link; or NULL is returned on error, 507 * error code is stored in errno 508 */ 509 LIBBPF_API struct bpf_link * 510 bpf_program__attach_uprobe_opts(const struct bpf_program *prog, pid_t pid, 511 const char *binary_path, size_t func_offset, 512 const struct bpf_uprobe_opts *opts); 513 514 struct bpf_usdt_opts { 515 /* size of this struct, for forward/backward compatibility */ 516 size_t sz; 517 /* custom user-provided value accessible through usdt_cookie() */ 518 __u64 usdt_cookie; 519 size_t :0; 520 }; 521 #define bpf_usdt_opts__last_field usdt_cookie 522 523 /** 524 * @brief **bpf_program__attach_usdt()** is just like 525 * bpf_program__attach_uprobe_opts() except it covers USDT (User-space 526 * Statically Defined Tracepoint) attachment, instead of attaching to 527 * user-space function entry or exit. 528 * 529 * @param prog BPF program to attach 530 * @param pid Process ID to attach the uprobe to, 0 for self (own process), 531 * -1 for all processes 532 * @param binary_path Path to binary that contains provided USDT probe 533 * @param usdt_provider USDT provider name 534 * @param usdt_name USDT probe name 535 * @param opts Options for altering program attachment 536 * @return Reference to the newly created BPF link; or NULL is returned on error, 537 * error code is stored in errno 538 */ 539 LIBBPF_API struct bpf_link * 540 bpf_program__attach_usdt(const struct bpf_program *prog, 541 pid_t pid, const char *binary_path, 542 const char *usdt_provider, const char *usdt_name, 543 const struct bpf_usdt_opts *opts); 544 545 struct bpf_tracepoint_opts { 546 /* size of this struct, for forward/backward compatiblity */ 547 size_t sz; 548 /* custom user-provided value fetchable through bpf_get_attach_cookie() */ 549 __u64 bpf_cookie; 550 }; 551 #define bpf_tracepoint_opts__last_field bpf_cookie 552 553 LIBBPF_API struct bpf_link * 554 bpf_program__attach_tracepoint(const struct bpf_program *prog, 555 const char *tp_category, 556 const char *tp_name); 557 LIBBPF_API struct bpf_link * 558 bpf_program__attach_tracepoint_opts(const struct bpf_program *prog, 559 const char *tp_category, 560 const char *tp_name, 561 const struct bpf_tracepoint_opts *opts); 562 563 LIBBPF_API struct bpf_link * 564 bpf_program__attach_raw_tracepoint(const struct bpf_program *prog, 565 const char *tp_name); 566 LIBBPF_API struct bpf_link * 567 bpf_program__attach_trace(const struct bpf_program *prog); 568 LIBBPF_API struct bpf_link * 569 bpf_program__attach_lsm(const struct bpf_program *prog); 570 LIBBPF_API struct bpf_link * 571 bpf_program__attach_cgroup(const struct bpf_program *prog, int cgroup_fd); 572 LIBBPF_API struct bpf_link * 573 bpf_program__attach_netns(const struct bpf_program *prog, int netns_fd); 574 LIBBPF_API struct bpf_link * 575 bpf_program__attach_xdp(const struct bpf_program *prog, int ifindex); 576 LIBBPF_API struct bpf_link * 577 bpf_program__attach_freplace(const struct bpf_program *prog, 578 int target_fd, const char *attach_func_name); 579 580 struct bpf_map; 581 582 LIBBPF_API struct bpf_link *bpf_map__attach_struct_ops(const struct bpf_map *map); 583 584 struct bpf_iter_attach_opts { 585 size_t sz; /* size of this struct for forward/backward compatibility */ 586 union bpf_iter_link_info *link_info; 587 __u32 link_info_len; 588 }; 589 #define bpf_iter_attach_opts__last_field link_info_len 590 591 LIBBPF_API struct bpf_link * 592 bpf_program__attach_iter(const struct bpf_program *prog, 593 const struct bpf_iter_attach_opts *opts); 594 595 /* 596 * Libbpf allows callers to adjust BPF programs before being loaded 597 * into kernel. One program in an object file can be transformed into 598 * multiple variants to be attached to different hooks. 599 * 600 * bpf_program_prep_t, bpf_program__set_prep and bpf_program__nth_fd 601 * form an API for this purpose. 602 * 603 * - bpf_program_prep_t: 604 * Defines a 'preprocessor', which is a caller defined function 605 * passed to libbpf through bpf_program__set_prep(), and will be 606 * called before program is loaded. The processor should adjust 607 * the program one time for each instance according to the instance id 608 * passed to it. 609 * 610 * - bpf_program__set_prep: 611 * Attaches a preprocessor to a BPF program. The number of instances 612 * that should be created is also passed through this function. 613 * 614 * - bpf_program__nth_fd: 615 * After the program is loaded, get resulting FD of a given instance 616 * of the BPF program. 617 * 618 * If bpf_program__set_prep() is not used, the program would be loaded 619 * without adjustment during bpf_object__load(). The program has only 620 * one instance. In this case bpf_program__fd(prog) is equal to 621 * bpf_program__nth_fd(prog, 0). 622 */ 623 struct bpf_prog_prep_result { 624 /* 625 * If not NULL, load new instruction array. 626 * If set to NULL, don't load this instance. 627 */ 628 struct bpf_insn *new_insn_ptr; 629 int new_insn_cnt; 630 631 /* If not NULL, result FD is written to it. */ 632 int *pfd; 633 }; 634 635 /* 636 * Parameters of bpf_program_prep_t: 637 * - prog: The bpf_program being loaded. 638 * - n: Index of instance being generated. 639 * - insns: BPF instructions array. 640 * - insns_cnt:Number of instructions in insns. 641 * - res: Output parameter, result of transformation. 642 * 643 * Return value: 644 * - Zero: pre-processing success. 645 * - Non-zero: pre-processing error, stop loading. 646 */ 647 typedef int (*bpf_program_prep_t)(struct bpf_program *prog, int n, 648 struct bpf_insn *insns, int insns_cnt, 649 struct bpf_prog_prep_result *res); 650 651 LIBBPF_DEPRECATED_SINCE(0, 7, "use bpf_program__insns() for getting bpf_program instructions") 652 LIBBPF_API int bpf_program__set_prep(struct bpf_program *prog, int nr_instance, 653 bpf_program_prep_t prep); 654 655 LIBBPF_DEPRECATED_SINCE(0, 7, "multi-instance bpf_program support is deprecated") 656 LIBBPF_API int bpf_program__nth_fd(const struct bpf_program *prog, int n); 657 658 /* 659 * Adjust type of BPF program. Default is kprobe. 660 */ 661 LIBBPF_DEPRECATED_SINCE(0, 8, "use bpf_program__set_type() instead") 662 LIBBPF_API int bpf_program__set_socket_filter(struct bpf_program *prog); 663 LIBBPF_DEPRECATED_SINCE(0, 8, "use bpf_program__set_type() instead") 664 LIBBPF_API int bpf_program__set_tracepoint(struct bpf_program *prog); 665 LIBBPF_DEPRECATED_SINCE(0, 8, "use bpf_program__set_type() instead") 666 LIBBPF_API int bpf_program__set_raw_tracepoint(struct bpf_program *prog); 667 LIBBPF_DEPRECATED_SINCE(0, 8, "use bpf_program__set_type() instead") 668 LIBBPF_API int bpf_program__set_kprobe(struct bpf_program *prog); 669 LIBBPF_DEPRECATED_SINCE(0, 8, "use bpf_program__set_type() instead") 670 LIBBPF_API int bpf_program__set_lsm(struct bpf_program *prog); 671 LIBBPF_DEPRECATED_SINCE(0, 8, "use bpf_program__set_type() instead") 672 LIBBPF_API int bpf_program__set_sched_cls(struct bpf_program *prog); 673 LIBBPF_DEPRECATED_SINCE(0, 8, "use bpf_program__set_type() instead") 674 LIBBPF_API int bpf_program__set_sched_act(struct bpf_program *prog); 675 LIBBPF_DEPRECATED_SINCE(0, 8, "use bpf_program__set_type() instead") 676 LIBBPF_API int bpf_program__set_xdp(struct bpf_program *prog); 677 LIBBPF_DEPRECATED_SINCE(0, 8, "use bpf_program__set_type() instead") 678 LIBBPF_API int bpf_program__set_perf_event(struct bpf_program *prog); 679 LIBBPF_DEPRECATED_SINCE(0, 8, "use bpf_program__set_type() instead") 680 LIBBPF_API int bpf_program__set_tracing(struct bpf_program *prog); 681 LIBBPF_DEPRECATED_SINCE(0, 8, "use bpf_program__set_type() instead") 682 LIBBPF_API int bpf_program__set_struct_ops(struct bpf_program *prog); 683 LIBBPF_DEPRECATED_SINCE(0, 8, "use bpf_program__set_type() instead") 684 LIBBPF_API int bpf_program__set_extension(struct bpf_program *prog); 685 LIBBPF_DEPRECATED_SINCE(0, 8, "use bpf_program__set_type() instead") 686 LIBBPF_API int bpf_program__set_sk_lookup(struct bpf_program *prog); 687 688 LIBBPF_API enum bpf_prog_type bpf_program__type(const struct bpf_program *prog); 689 LIBBPF_API void bpf_program__set_type(struct bpf_program *prog, 690 enum bpf_prog_type type); 691 692 LIBBPF_API enum bpf_attach_type 693 bpf_program__expected_attach_type(const struct bpf_program *prog); 694 LIBBPF_API void 695 bpf_program__set_expected_attach_type(struct bpf_program *prog, 696 enum bpf_attach_type type); 697 698 LIBBPF_API __u32 bpf_program__flags(const struct bpf_program *prog); 699 LIBBPF_API int bpf_program__set_flags(struct bpf_program *prog, __u32 flags); 700 701 /* Per-program log level and log buffer getters/setters. 702 * See bpf_object_open_opts comments regarding log_level and log_buf 703 * interactions. 704 */ 705 LIBBPF_API __u32 bpf_program__log_level(const struct bpf_program *prog); 706 LIBBPF_API int bpf_program__set_log_level(struct bpf_program *prog, __u32 log_level); 707 LIBBPF_API const char *bpf_program__log_buf(const struct bpf_program *prog, size_t *log_size); 708 LIBBPF_API int bpf_program__set_log_buf(struct bpf_program *prog, char *log_buf, size_t log_size); 709 710 LIBBPF_API int 711 bpf_program__set_attach_target(struct bpf_program *prog, int attach_prog_fd, 712 const char *attach_func_name); 713 714 LIBBPF_DEPRECATED_SINCE(0, 8, "use bpf_program__type() instead") 715 LIBBPF_API bool bpf_program__is_socket_filter(const struct bpf_program *prog); 716 LIBBPF_DEPRECATED_SINCE(0, 8, "use bpf_program__type() instead") 717 LIBBPF_API bool bpf_program__is_tracepoint(const struct bpf_program *prog); 718 LIBBPF_DEPRECATED_SINCE(0, 8, "use bpf_program__type() instead") 719 LIBBPF_API bool bpf_program__is_raw_tracepoint(const struct bpf_program *prog); 720 LIBBPF_DEPRECATED_SINCE(0, 8, "use bpf_program__type() instead") 721 LIBBPF_API bool bpf_program__is_kprobe(const struct bpf_program *prog); 722 LIBBPF_DEPRECATED_SINCE(0, 8, "use bpf_program__type() instead") 723 LIBBPF_API bool bpf_program__is_lsm(const struct bpf_program *prog); 724 LIBBPF_DEPRECATED_SINCE(0, 8, "use bpf_program__type() instead") 725 LIBBPF_API bool bpf_program__is_sched_cls(const struct bpf_program *prog); 726 LIBBPF_DEPRECATED_SINCE(0, 8, "use bpf_program__type() instead") 727 LIBBPF_API bool bpf_program__is_sched_act(const struct bpf_program *prog); 728 LIBBPF_DEPRECATED_SINCE(0, 8, "use bpf_program__type() instead") 729 LIBBPF_API bool bpf_program__is_xdp(const struct bpf_program *prog); 730 LIBBPF_DEPRECATED_SINCE(0, 8, "use bpf_program__type() instead") 731 LIBBPF_API bool bpf_program__is_perf_event(const struct bpf_program *prog); 732 LIBBPF_DEPRECATED_SINCE(0, 8, "use bpf_program__type() instead") 733 LIBBPF_API bool bpf_program__is_tracing(const struct bpf_program *prog); 734 LIBBPF_DEPRECATED_SINCE(0, 8, "use bpf_program__type() instead") 735 LIBBPF_API bool bpf_program__is_struct_ops(const struct bpf_program *prog); 736 LIBBPF_DEPRECATED_SINCE(0, 8, "use bpf_program__type() instead") 737 LIBBPF_API bool bpf_program__is_extension(const struct bpf_program *prog); 738 LIBBPF_DEPRECATED_SINCE(0, 8, "use bpf_program__type() instead") 739 LIBBPF_API bool bpf_program__is_sk_lookup(const struct bpf_program *prog); 740 741 /* 742 * No need for __attribute__((packed)), all members of 'bpf_map_def' 743 * are all aligned. In addition, using __attribute__((packed)) 744 * would trigger a -Wpacked warning message, and lead to an error 745 * if -Werror is set. 746 */ 747 struct bpf_map_def { 748 unsigned int type; 749 unsigned int key_size; 750 unsigned int value_size; 751 unsigned int max_entries; 752 unsigned int map_flags; 753 }; 754 755 /** 756 * @brief **bpf_object__find_map_by_name()** returns BPF map of 757 * the given name, if it exists within the passed BPF object 758 * @param obj BPF object 759 * @param name name of the BPF map 760 * @return BPF map instance, if such map exists within the BPF object; 761 * or NULL otherwise. 762 */ 763 LIBBPF_API struct bpf_map * 764 bpf_object__find_map_by_name(const struct bpf_object *obj, const char *name); 765 766 LIBBPF_API int 767 bpf_object__find_map_fd_by_name(const struct bpf_object *obj, const char *name); 768 769 /* 770 * Get bpf_map through the offset of corresponding struct bpf_map_def 771 * in the BPF object file. 772 */ 773 LIBBPF_API LIBBPF_DEPRECATED_SINCE(0, 8, "use bpf_object__find_map_by_name() instead") 774 struct bpf_map * 775 bpf_object__find_map_by_offset(struct bpf_object *obj, size_t offset); 776 777 LIBBPF_API LIBBPF_DEPRECATED_SINCE(0, 7, "use bpf_object__next_map() instead") 778 struct bpf_map *bpf_map__next(const struct bpf_map *map, const struct bpf_object *obj); 779 LIBBPF_API struct bpf_map * 780 bpf_object__next_map(const struct bpf_object *obj, const struct bpf_map *map); 781 782 #define bpf_object__for_each_map(pos, obj) \ 783 for ((pos) = bpf_object__next_map((obj), NULL); \ 784 (pos) != NULL; \ 785 (pos) = bpf_object__next_map((obj), (pos))) 786 #define bpf_map__for_each bpf_object__for_each_map 787 788 LIBBPF_API LIBBPF_DEPRECATED_SINCE(0, 7, "use bpf_object__prev_map() instead") 789 struct bpf_map *bpf_map__prev(const struct bpf_map *map, const struct bpf_object *obj); 790 LIBBPF_API struct bpf_map * 791 bpf_object__prev_map(const struct bpf_object *obj, const struct bpf_map *map); 792 793 /** 794 * @brief **bpf_map__fd()** gets the file descriptor of the passed 795 * BPF map 796 * @param map the BPF map instance 797 * @return the file descriptor; or -EINVAL in case of an error 798 */ 799 LIBBPF_API int bpf_map__fd(const struct bpf_map *map); 800 LIBBPF_API int bpf_map__reuse_fd(struct bpf_map *map, int fd); 801 /* get map definition */ 802 LIBBPF_API LIBBPF_DEPRECATED_SINCE(0, 8, "use appropriate getters or setters instead") 803 const struct bpf_map_def *bpf_map__def(const struct bpf_map *map); 804 /* get map name */ 805 LIBBPF_API const char *bpf_map__name(const struct bpf_map *map); 806 /* get/set map type */ 807 LIBBPF_API enum bpf_map_type bpf_map__type(const struct bpf_map *map); 808 LIBBPF_API int bpf_map__set_type(struct bpf_map *map, enum bpf_map_type type); 809 /* get/set map size (max_entries) */ 810 LIBBPF_API __u32 bpf_map__max_entries(const struct bpf_map *map); 811 LIBBPF_API int bpf_map__set_max_entries(struct bpf_map *map, __u32 max_entries); 812 LIBBPF_DEPRECATED_SINCE(0, 8, "use bpf_map__set_max_entries() instead") 813 LIBBPF_API int bpf_map__resize(struct bpf_map *map, __u32 max_entries); 814 /* get/set map flags */ 815 LIBBPF_API __u32 bpf_map__map_flags(const struct bpf_map *map); 816 LIBBPF_API int bpf_map__set_map_flags(struct bpf_map *map, __u32 flags); 817 /* get/set map NUMA node */ 818 LIBBPF_API __u32 bpf_map__numa_node(const struct bpf_map *map); 819 LIBBPF_API int bpf_map__set_numa_node(struct bpf_map *map, __u32 numa_node); 820 /* get/set map key size */ 821 LIBBPF_API __u32 bpf_map__key_size(const struct bpf_map *map); 822 LIBBPF_API int bpf_map__set_key_size(struct bpf_map *map, __u32 size); 823 /* get/set map value size */ 824 LIBBPF_API __u32 bpf_map__value_size(const struct bpf_map *map); 825 LIBBPF_API int bpf_map__set_value_size(struct bpf_map *map, __u32 size); 826 /* get map key/value BTF type IDs */ 827 LIBBPF_API __u32 bpf_map__btf_key_type_id(const struct bpf_map *map); 828 LIBBPF_API __u32 bpf_map__btf_value_type_id(const struct bpf_map *map); 829 /* get/set map if_index */ 830 LIBBPF_API __u32 bpf_map__ifindex(const struct bpf_map *map); 831 LIBBPF_API int bpf_map__set_ifindex(struct bpf_map *map, __u32 ifindex); 832 /* get/set map map_extra flags */ 833 LIBBPF_API __u64 bpf_map__map_extra(const struct bpf_map *map); 834 LIBBPF_API int bpf_map__set_map_extra(struct bpf_map *map, __u64 map_extra); 835 836 typedef void (*bpf_map_clear_priv_t)(struct bpf_map *, void *); 837 LIBBPF_DEPRECATED_SINCE(0, 7, "storage via set_priv/priv is deprecated") 838 LIBBPF_API int bpf_map__set_priv(struct bpf_map *map, void *priv, 839 bpf_map_clear_priv_t clear_priv); 840 LIBBPF_DEPRECATED_SINCE(0, 7, "storage via set_priv/priv is deprecated") 841 LIBBPF_API void *bpf_map__priv(const struct bpf_map *map); 842 LIBBPF_API int bpf_map__set_initial_value(struct bpf_map *map, 843 const void *data, size_t size); 844 LIBBPF_API const void *bpf_map__initial_value(struct bpf_map *map, size_t *psize); 845 LIBBPF_DEPRECATED_SINCE(0, 8, "use bpf_map__type() instead") 846 LIBBPF_API bool bpf_map__is_offload_neutral(const struct bpf_map *map); 847 848 /** 849 * @brief **bpf_map__is_internal()** tells the caller whether or not the 850 * passed map is a special map created by libbpf automatically for things like 851 * global variables, __ksym externs, Kconfig values, etc 852 * @param map the bpf_map 853 * @return true, if the map is an internal map; false, otherwise 854 */ 855 LIBBPF_API bool bpf_map__is_internal(const struct bpf_map *map); 856 LIBBPF_API int bpf_map__set_pin_path(struct bpf_map *map, const char *path); 857 LIBBPF_API const char *bpf_map__pin_path(const struct bpf_map *map); 858 LIBBPF_API bool bpf_map__is_pinned(const struct bpf_map *map); 859 LIBBPF_API int bpf_map__pin(struct bpf_map *map, const char *path); 860 LIBBPF_API int bpf_map__unpin(struct bpf_map *map, const char *path); 861 862 LIBBPF_API int bpf_map__set_inner_map_fd(struct bpf_map *map, int fd); 863 LIBBPF_API struct bpf_map *bpf_map__inner_map(struct bpf_map *map); 864 865 /** 866 * @brief **libbpf_get_error()** extracts the error code from the passed 867 * pointer 868 * @param ptr pointer returned from libbpf API function 869 * @return error code; or 0 if no error occured 870 * 871 * Many libbpf API functions which return pointers have logic to encode error 872 * codes as pointers, and do not return NULL. Meaning **libbpf_get_error()** 873 * should be used on the return value from these functions immediately after 874 * calling the API function, with no intervening calls that could clobber the 875 * `errno` variable. Consult the individual functions documentation to verify 876 * if this logic applies should be used. 877 * 878 * For these API functions, if `libbpf_set_strict_mode(LIBBPF_STRICT_CLEAN_PTRS)` 879 * is enabled, NULL is returned on error instead. 880 * 881 * If ptr is NULL, then errno should be already set by the failing 882 * API, because libbpf never returns NULL on success and it now always 883 * sets errno on error. 884 * 885 * Example usage: 886 * 887 * struct perf_buffer *pb; 888 * 889 * pb = perf_buffer__new(bpf_map__fd(obj->maps.events), PERF_BUFFER_PAGES, &opts); 890 * err = libbpf_get_error(pb); 891 * if (err) { 892 * pb = NULL; 893 * fprintf(stderr, "failed to open perf buffer: %d\n", err); 894 * goto cleanup; 895 * } 896 */ 897 LIBBPF_API long libbpf_get_error(const void *ptr); 898 899 struct bpf_prog_load_attr { 900 const char *file; 901 enum bpf_prog_type prog_type; 902 enum bpf_attach_type expected_attach_type; 903 int ifindex; 904 int log_level; 905 int prog_flags; 906 }; 907 908 LIBBPF_DEPRECATED_SINCE(0, 8, "use bpf_object__open() and bpf_object__load() instead") 909 LIBBPF_API int bpf_prog_load_xattr(const struct bpf_prog_load_attr *attr, 910 struct bpf_object **pobj, int *prog_fd); 911 LIBBPF_DEPRECATED_SINCE(0, 7, "use bpf_object__open() and bpf_object__load() instead") 912 LIBBPF_API int bpf_prog_load_deprecated(const char *file, enum bpf_prog_type type, 913 struct bpf_object **pobj, int *prog_fd); 914 915 /* XDP related API */ 916 struct xdp_link_info { 917 __u32 prog_id; 918 __u32 drv_prog_id; 919 __u32 hw_prog_id; 920 __u32 skb_prog_id; 921 __u8 attach_mode; 922 }; 923 924 struct bpf_xdp_set_link_opts { 925 size_t sz; 926 int old_fd; 927 size_t :0; 928 }; 929 #define bpf_xdp_set_link_opts__last_field old_fd 930 931 LIBBPF_DEPRECATED_SINCE(0, 8, "use bpf_xdp_attach() instead") 932 LIBBPF_API int bpf_set_link_xdp_fd(int ifindex, int fd, __u32 flags); 933 LIBBPF_DEPRECATED_SINCE(0, 8, "use bpf_xdp_attach() instead") 934 LIBBPF_API int bpf_set_link_xdp_fd_opts(int ifindex, int fd, __u32 flags, 935 const struct bpf_xdp_set_link_opts *opts); 936 LIBBPF_DEPRECATED_SINCE(0, 8, "use bpf_xdp_query_id() instead") 937 LIBBPF_API int bpf_get_link_xdp_id(int ifindex, __u32 *prog_id, __u32 flags); 938 LIBBPF_DEPRECATED_SINCE(0, 8, "use bpf_xdp_query() instead") 939 LIBBPF_API int bpf_get_link_xdp_info(int ifindex, struct xdp_link_info *info, 940 size_t info_size, __u32 flags); 941 942 struct bpf_xdp_attach_opts { 943 size_t sz; 944 int old_prog_fd; 945 size_t :0; 946 }; 947 #define bpf_xdp_attach_opts__last_field old_prog_fd 948 949 struct bpf_xdp_query_opts { 950 size_t sz; 951 __u32 prog_id; /* output */ 952 __u32 drv_prog_id; /* output */ 953 __u32 hw_prog_id; /* output */ 954 __u32 skb_prog_id; /* output */ 955 __u8 attach_mode; /* output */ 956 size_t :0; 957 }; 958 #define bpf_xdp_query_opts__last_field attach_mode 959 960 LIBBPF_API int bpf_xdp_attach(int ifindex, int prog_fd, __u32 flags, 961 const struct bpf_xdp_attach_opts *opts); 962 LIBBPF_API int bpf_xdp_detach(int ifindex, __u32 flags, 963 const struct bpf_xdp_attach_opts *opts); 964 LIBBPF_API int bpf_xdp_query(int ifindex, int flags, struct bpf_xdp_query_opts *opts); 965 LIBBPF_API int bpf_xdp_query_id(int ifindex, int flags, __u32 *prog_id); 966 967 /* TC related API */ 968 enum bpf_tc_attach_point { 969 BPF_TC_INGRESS = 1 << 0, 970 BPF_TC_EGRESS = 1 << 1, 971 BPF_TC_CUSTOM = 1 << 2, 972 }; 973 974 #define BPF_TC_PARENT(a, b) \ 975 ((((a) << 16) & 0xFFFF0000U) | ((b) & 0x0000FFFFU)) 976 977 enum bpf_tc_flags { 978 BPF_TC_F_REPLACE = 1 << 0, 979 }; 980 981 struct bpf_tc_hook { 982 size_t sz; 983 int ifindex; 984 enum bpf_tc_attach_point attach_point; 985 __u32 parent; 986 size_t :0; 987 }; 988 #define bpf_tc_hook__last_field parent 989 990 struct bpf_tc_opts { 991 size_t sz; 992 int prog_fd; 993 __u32 flags; 994 __u32 prog_id; 995 __u32 handle; 996 __u32 priority; 997 size_t :0; 998 }; 999 #define bpf_tc_opts__last_field priority 1000 1001 LIBBPF_API int bpf_tc_hook_create(struct bpf_tc_hook *hook); 1002 LIBBPF_API int bpf_tc_hook_destroy(struct bpf_tc_hook *hook); 1003 LIBBPF_API int bpf_tc_attach(const struct bpf_tc_hook *hook, 1004 struct bpf_tc_opts *opts); 1005 LIBBPF_API int bpf_tc_detach(const struct bpf_tc_hook *hook, 1006 const struct bpf_tc_opts *opts); 1007 LIBBPF_API int bpf_tc_query(const struct bpf_tc_hook *hook, 1008 struct bpf_tc_opts *opts); 1009 1010 /* Ring buffer APIs */ 1011 struct ring_buffer; 1012 1013 typedef int (*ring_buffer_sample_fn)(void *ctx, void *data, size_t size); 1014 1015 struct ring_buffer_opts { 1016 size_t sz; /* size of this struct, for forward/backward compatiblity */ 1017 }; 1018 1019 #define ring_buffer_opts__last_field sz 1020 1021 LIBBPF_API struct ring_buffer * 1022 ring_buffer__new(int map_fd, ring_buffer_sample_fn sample_cb, void *ctx, 1023 const struct ring_buffer_opts *opts); 1024 LIBBPF_API void ring_buffer__free(struct ring_buffer *rb); 1025 LIBBPF_API int ring_buffer__add(struct ring_buffer *rb, int map_fd, 1026 ring_buffer_sample_fn sample_cb, void *ctx); 1027 LIBBPF_API int ring_buffer__poll(struct ring_buffer *rb, int timeout_ms); 1028 LIBBPF_API int ring_buffer__consume(struct ring_buffer *rb); 1029 LIBBPF_API int ring_buffer__epoll_fd(const struct ring_buffer *rb); 1030 1031 /* Perf buffer APIs */ 1032 struct perf_buffer; 1033 1034 typedef void (*perf_buffer_sample_fn)(void *ctx, int cpu, 1035 void *data, __u32 size); 1036 typedef void (*perf_buffer_lost_fn)(void *ctx, int cpu, __u64 cnt); 1037 1038 /* common use perf buffer options */ 1039 struct perf_buffer_opts { 1040 union { 1041 size_t sz; 1042 struct { /* DEPRECATED: will be removed in v1.0 */ 1043 /* if specified, sample_cb is called for each sample */ 1044 perf_buffer_sample_fn sample_cb; 1045 /* if specified, lost_cb is called for each batch of lost samples */ 1046 perf_buffer_lost_fn lost_cb; 1047 /* ctx is provided to sample_cb and lost_cb */ 1048 void *ctx; 1049 }; 1050 }; 1051 }; 1052 #define perf_buffer_opts__last_field sz 1053 1054 /** 1055 * @brief **perf_buffer__new()** creates BPF perfbuf manager for a specified 1056 * BPF_PERF_EVENT_ARRAY map 1057 * @param map_fd FD of BPF_PERF_EVENT_ARRAY BPF map that will be used by BPF 1058 * code to send data over to user-space 1059 * @param page_cnt number of memory pages allocated for each per-CPU buffer 1060 * @param sample_cb function called on each received data record 1061 * @param lost_cb function called when record loss has occurred 1062 * @param ctx user-provided extra context passed into *sample_cb* and *lost_cb* 1063 * @return a new instance of struct perf_buffer on success, NULL on error with 1064 * *errno* containing an error code 1065 */ 1066 LIBBPF_API struct perf_buffer * 1067 perf_buffer__new(int map_fd, size_t page_cnt, 1068 perf_buffer_sample_fn sample_cb, perf_buffer_lost_fn lost_cb, void *ctx, 1069 const struct perf_buffer_opts *opts); 1070 1071 LIBBPF_API struct perf_buffer * 1072 perf_buffer__new_v0_6_0(int map_fd, size_t page_cnt, 1073 perf_buffer_sample_fn sample_cb, perf_buffer_lost_fn lost_cb, void *ctx, 1074 const struct perf_buffer_opts *opts); 1075 1076 LIBBPF_API LIBBPF_DEPRECATED_SINCE(0, 7, "use new variant of perf_buffer__new() instead") 1077 struct perf_buffer *perf_buffer__new_deprecated(int map_fd, size_t page_cnt, 1078 const struct perf_buffer_opts *opts); 1079 1080 #define perf_buffer__new(...) ___libbpf_overload(___perf_buffer_new, __VA_ARGS__) 1081 #define ___perf_buffer_new6(map_fd, page_cnt, sample_cb, lost_cb, ctx, opts) \ 1082 perf_buffer__new(map_fd, page_cnt, sample_cb, lost_cb, ctx, opts) 1083 #define ___perf_buffer_new3(map_fd, page_cnt, opts) \ 1084 perf_buffer__new_deprecated(map_fd, page_cnt, opts) 1085 1086 enum bpf_perf_event_ret { 1087 LIBBPF_PERF_EVENT_DONE = 0, 1088 LIBBPF_PERF_EVENT_ERROR = -1, 1089 LIBBPF_PERF_EVENT_CONT = -2, 1090 }; 1091 1092 struct perf_event_header; 1093 1094 typedef enum bpf_perf_event_ret 1095 (*perf_buffer_event_fn)(void *ctx, int cpu, struct perf_event_header *event); 1096 1097 /* raw perf buffer options, giving most power and control */ 1098 struct perf_buffer_raw_opts { 1099 union { 1100 struct { 1101 size_t sz; 1102 long :0; 1103 long :0; 1104 }; 1105 struct { /* DEPRECATED: will be removed in v1.0 */ 1106 /* perf event attrs passed directly into perf_event_open() */ 1107 struct perf_event_attr *attr; 1108 /* raw event callback */ 1109 perf_buffer_event_fn event_cb; 1110 /* ctx is provided to event_cb */ 1111 void *ctx; 1112 }; 1113 }; 1114 /* if cpu_cnt == 0, open all on all possible CPUs (up to the number of 1115 * max_entries of given PERF_EVENT_ARRAY map) 1116 */ 1117 int cpu_cnt; 1118 /* if cpu_cnt > 0, cpus is an array of CPUs to open ring buffers on */ 1119 int *cpus; 1120 /* if cpu_cnt > 0, map_keys specify map keys to set per-CPU FDs for */ 1121 int *map_keys; 1122 }; 1123 #define perf_buffer_raw_opts__last_field map_keys 1124 1125 LIBBPF_API struct perf_buffer * 1126 perf_buffer__new_raw(int map_fd, size_t page_cnt, struct perf_event_attr *attr, 1127 perf_buffer_event_fn event_cb, void *ctx, 1128 const struct perf_buffer_raw_opts *opts); 1129 1130 LIBBPF_API struct perf_buffer * 1131 perf_buffer__new_raw_v0_6_0(int map_fd, size_t page_cnt, struct perf_event_attr *attr, 1132 perf_buffer_event_fn event_cb, void *ctx, 1133 const struct perf_buffer_raw_opts *opts); 1134 1135 LIBBPF_API LIBBPF_DEPRECATED_SINCE(0, 7, "use new variant of perf_buffer__new_raw() instead") 1136 struct perf_buffer *perf_buffer__new_raw_deprecated(int map_fd, size_t page_cnt, 1137 const struct perf_buffer_raw_opts *opts); 1138 1139 #define perf_buffer__new_raw(...) ___libbpf_overload(___perf_buffer_new_raw, __VA_ARGS__) 1140 #define ___perf_buffer_new_raw6(map_fd, page_cnt, attr, event_cb, ctx, opts) \ 1141 perf_buffer__new_raw(map_fd, page_cnt, attr, event_cb, ctx, opts) 1142 #define ___perf_buffer_new_raw3(map_fd, page_cnt, opts) \ 1143 perf_buffer__new_raw_deprecated(map_fd, page_cnt, opts) 1144 1145 LIBBPF_API void perf_buffer__free(struct perf_buffer *pb); 1146 LIBBPF_API int perf_buffer__epoll_fd(const struct perf_buffer *pb); 1147 LIBBPF_API int perf_buffer__poll(struct perf_buffer *pb, int timeout_ms); 1148 LIBBPF_API int perf_buffer__consume(struct perf_buffer *pb); 1149 LIBBPF_API int perf_buffer__consume_buffer(struct perf_buffer *pb, size_t buf_idx); 1150 LIBBPF_API size_t perf_buffer__buffer_cnt(const struct perf_buffer *pb); 1151 LIBBPF_API int perf_buffer__buffer_fd(const struct perf_buffer *pb, size_t buf_idx); 1152 1153 typedef enum bpf_perf_event_ret 1154 (*bpf_perf_event_print_t)(struct perf_event_header *hdr, 1155 void *private_data); 1156 LIBBPF_DEPRECATED_SINCE(0, 8, "use perf_buffer__poll() or perf_buffer__consume() instead") 1157 LIBBPF_API enum bpf_perf_event_ret 1158 bpf_perf_event_read_simple(void *mmap_mem, size_t mmap_size, size_t page_size, 1159 void **copy_mem, size_t *copy_size, 1160 bpf_perf_event_print_t fn, void *private_data); 1161 1162 struct bpf_prog_linfo; 1163 struct bpf_prog_info; 1164 1165 LIBBPF_API void bpf_prog_linfo__free(struct bpf_prog_linfo *prog_linfo); 1166 LIBBPF_API struct bpf_prog_linfo * 1167 bpf_prog_linfo__new(const struct bpf_prog_info *info); 1168 LIBBPF_API const struct bpf_line_info * 1169 bpf_prog_linfo__lfind_addr_func(const struct bpf_prog_linfo *prog_linfo, 1170 __u64 addr, __u32 func_idx, __u32 nr_skip); 1171 LIBBPF_API const struct bpf_line_info * 1172 bpf_prog_linfo__lfind(const struct bpf_prog_linfo *prog_linfo, 1173 __u32 insn_off, __u32 nr_skip); 1174 1175 /* 1176 * Probe for supported system features 1177 * 1178 * Note that running many of these probes in a short amount of time can cause 1179 * the kernel to reach the maximal size of lockable memory allowed for the 1180 * user, causing subsequent probes to fail. In this case, the caller may want 1181 * to adjust that limit with setrlimit(). 1182 */ 1183 LIBBPF_DEPRECATED_SINCE(0, 8, "use libbpf_probe_bpf_prog_type() instead") 1184 LIBBPF_API bool bpf_probe_prog_type(enum bpf_prog_type prog_type, __u32 ifindex); 1185 LIBBPF_DEPRECATED_SINCE(0, 8, "use libbpf_probe_bpf_map_type() instead") 1186 LIBBPF_API bool bpf_probe_map_type(enum bpf_map_type map_type, __u32 ifindex); 1187 LIBBPF_DEPRECATED_SINCE(0, 8, "use libbpf_probe_bpf_helper() instead") 1188 LIBBPF_API bool bpf_probe_helper(enum bpf_func_id id, enum bpf_prog_type prog_type, __u32 ifindex); 1189 LIBBPF_DEPRECATED_SINCE(0, 8, "implement your own or use bpftool for feature detection") 1190 LIBBPF_API bool bpf_probe_large_insn_limit(__u32 ifindex); 1191 1192 /** 1193 * @brief **libbpf_probe_bpf_prog_type()** detects if host kernel supports 1194 * BPF programs of a given type. 1195 * @param prog_type BPF program type to detect kernel support for 1196 * @param opts reserved for future extensibility, should be NULL 1197 * @return 1, if given program type is supported; 0, if given program type is 1198 * not supported; negative error code if feature detection failed or can't be 1199 * performed 1200 * 1201 * Make sure the process has required set of CAP_* permissions (or runs as 1202 * root) when performing feature checking. 1203 */ 1204 LIBBPF_API int libbpf_probe_bpf_prog_type(enum bpf_prog_type prog_type, const void *opts); 1205 /** 1206 * @brief **libbpf_probe_bpf_map_type()** detects if host kernel supports 1207 * BPF maps of a given type. 1208 * @param map_type BPF map type to detect kernel support for 1209 * @param opts reserved for future extensibility, should be NULL 1210 * @return 1, if given map type is supported; 0, if given map type is 1211 * not supported; negative error code if feature detection failed or can't be 1212 * performed 1213 * 1214 * Make sure the process has required set of CAP_* permissions (or runs as 1215 * root) when performing feature checking. 1216 */ 1217 LIBBPF_API int libbpf_probe_bpf_map_type(enum bpf_map_type map_type, const void *opts); 1218 /** 1219 * @brief **libbpf_probe_bpf_helper()** detects if host kernel supports the 1220 * use of a given BPF helper from specified BPF program type. 1221 * @param prog_type BPF program type used to check the support of BPF helper 1222 * @param helper_id BPF helper ID (enum bpf_func_id) to check support for 1223 * @param opts reserved for future extensibility, should be NULL 1224 * @return 1, if given combination of program type and helper is supported; 0, 1225 * if the combination is not supported; negative error code if feature 1226 * detection for provided input arguments failed or can't be performed 1227 * 1228 * Make sure the process has required set of CAP_* permissions (or runs as 1229 * root) when performing feature checking. 1230 */ 1231 LIBBPF_API int libbpf_probe_bpf_helper(enum bpf_prog_type prog_type, 1232 enum bpf_func_id helper_id, const void *opts); 1233 1234 /* 1235 * Get bpf_prog_info in continuous memory 1236 * 1237 * struct bpf_prog_info has multiple arrays. The user has option to choose 1238 * arrays to fetch from kernel. The following APIs provide an uniform way to 1239 * fetch these data. All arrays in bpf_prog_info are stored in a single 1240 * continuous memory region. This makes it easy to store the info in a 1241 * file. 1242 * 1243 * Before writing bpf_prog_info_linear to files, it is necessary to 1244 * translate pointers in bpf_prog_info to offsets. Helper functions 1245 * bpf_program__bpil_addr_to_offs() and bpf_program__bpil_offs_to_addr() 1246 * are introduced to switch between pointers and offsets. 1247 * 1248 * Examples: 1249 * # To fetch map_ids and prog_tags: 1250 * __u64 arrays = (1UL << BPF_PROG_INFO_MAP_IDS) | 1251 * (1UL << BPF_PROG_INFO_PROG_TAGS); 1252 * struct bpf_prog_info_linear *info_linear = 1253 * bpf_program__get_prog_info_linear(fd, arrays); 1254 * 1255 * # To save data in file 1256 * bpf_program__bpil_addr_to_offs(info_linear); 1257 * write(f, info_linear, sizeof(*info_linear) + info_linear->data_len); 1258 * 1259 * # To read data from file 1260 * read(f, info_linear, <proper_size>); 1261 * bpf_program__bpil_offs_to_addr(info_linear); 1262 */ 1263 enum bpf_prog_info_array { 1264 BPF_PROG_INFO_FIRST_ARRAY = 0, 1265 BPF_PROG_INFO_JITED_INSNS = 0, 1266 BPF_PROG_INFO_XLATED_INSNS, 1267 BPF_PROG_INFO_MAP_IDS, 1268 BPF_PROG_INFO_JITED_KSYMS, 1269 BPF_PROG_INFO_JITED_FUNC_LENS, 1270 BPF_PROG_INFO_FUNC_INFO, 1271 BPF_PROG_INFO_LINE_INFO, 1272 BPF_PROG_INFO_JITED_LINE_INFO, 1273 BPF_PROG_INFO_PROG_TAGS, 1274 BPF_PROG_INFO_LAST_ARRAY, 1275 }; 1276 1277 struct bpf_prog_info_linear { 1278 /* size of struct bpf_prog_info, when the tool is compiled */ 1279 __u32 info_len; 1280 /* total bytes allocated for data, round up to 8 bytes */ 1281 __u32 data_len; 1282 /* which arrays are included in data */ 1283 __u64 arrays; 1284 struct bpf_prog_info info; 1285 __u8 data[]; 1286 }; 1287 1288 LIBBPF_DEPRECATED_SINCE(0, 6, "use a custom linear prog_info wrapper") 1289 LIBBPF_API struct bpf_prog_info_linear * 1290 bpf_program__get_prog_info_linear(int fd, __u64 arrays); 1291 1292 LIBBPF_DEPRECATED_SINCE(0, 6, "use a custom linear prog_info wrapper") 1293 LIBBPF_API void 1294 bpf_program__bpil_addr_to_offs(struct bpf_prog_info_linear *info_linear); 1295 1296 LIBBPF_DEPRECATED_SINCE(0, 6, "use a custom linear prog_info wrapper") 1297 LIBBPF_API void 1298 bpf_program__bpil_offs_to_addr(struct bpf_prog_info_linear *info_linear); 1299 1300 /** 1301 * @brief **libbpf_num_possible_cpus()** is a helper function to get the 1302 * number of possible CPUs that the host kernel supports and expects. 1303 * @return number of possible CPUs; or error code on failure 1304 * 1305 * Example usage: 1306 * 1307 * int ncpus = libbpf_num_possible_cpus(); 1308 * if (ncpus < 0) { 1309 * // error handling 1310 * } 1311 * long values[ncpus]; 1312 * bpf_map_lookup_elem(per_cpu_map_fd, key, values); 1313 */ 1314 LIBBPF_API int libbpf_num_possible_cpus(void); 1315 1316 struct bpf_map_skeleton { 1317 const char *name; 1318 struct bpf_map **map; 1319 void **mmaped; 1320 }; 1321 1322 struct bpf_prog_skeleton { 1323 const char *name; 1324 struct bpf_program **prog; 1325 struct bpf_link **link; 1326 }; 1327 1328 struct bpf_object_skeleton { 1329 size_t sz; /* size of this struct, for forward/backward compatibility */ 1330 1331 const char *name; 1332 const void *data; 1333 size_t data_sz; 1334 1335 struct bpf_object **obj; 1336 1337 int map_cnt; 1338 int map_skel_sz; /* sizeof(struct bpf_map_skeleton) */ 1339 struct bpf_map_skeleton *maps; 1340 1341 int prog_cnt; 1342 int prog_skel_sz; /* sizeof(struct bpf_prog_skeleton) */ 1343 struct bpf_prog_skeleton *progs; 1344 }; 1345 1346 LIBBPF_API int 1347 bpf_object__open_skeleton(struct bpf_object_skeleton *s, 1348 const struct bpf_object_open_opts *opts); 1349 LIBBPF_API int bpf_object__load_skeleton(struct bpf_object_skeleton *s); 1350 LIBBPF_API int bpf_object__attach_skeleton(struct bpf_object_skeleton *s); 1351 LIBBPF_API void bpf_object__detach_skeleton(struct bpf_object_skeleton *s); 1352 LIBBPF_API void bpf_object__destroy_skeleton(struct bpf_object_skeleton *s); 1353 1354 struct bpf_var_skeleton { 1355 const char *name; 1356 struct bpf_map **map; 1357 void **addr; 1358 }; 1359 1360 struct bpf_object_subskeleton { 1361 size_t sz; /* size of this struct, for forward/backward compatibility */ 1362 1363 const struct bpf_object *obj; 1364 1365 int map_cnt; 1366 int map_skel_sz; /* sizeof(struct bpf_map_skeleton) */ 1367 struct bpf_map_skeleton *maps; 1368 1369 int prog_cnt; 1370 int prog_skel_sz; /* sizeof(struct bpf_prog_skeleton) */ 1371 struct bpf_prog_skeleton *progs; 1372 1373 int var_cnt; 1374 int var_skel_sz; /* sizeof(struct bpf_var_skeleton) */ 1375 struct bpf_var_skeleton *vars; 1376 }; 1377 1378 LIBBPF_API int 1379 bpf_object__open_subskeleton(struct bpf_object_subskeleton *s); 1380 LIBBPF_API void 1381 bpf_object__destroy_subskeleton(struct bpf_object_subskeleton *s); 1382 1383 struct gen_loader_opts { 1384 size_t sz; /* size of this struct, for forward/backward compatiblity */ 1385 const char *data; 1386 const char *insns; 1387 __u32 data_sz; 1388 __u32 insns_sz; 1389 }; 1390 1391 #define gen_loader_opts__last_field insns_sz 1392 LIBBPF_API int bpf_object__gen_loader(struct bpf_object *obj, 1393 struct gen_loader_opts *opts); 1394 1395 enum libbpf_tristate { 1396 TRI_NO = 0, 1397 TRI_YES = 1, 1398 TRI_MODULE = 2, 1399 }; 1400 1401 struct bpf_linker_opts { 1402 /* size of this struct, for forward/backward compatiblity */ 1403 size_t sz; 1404 }; 1405 #define bpf_linker_opts__last_field sz 1406 1407 struct bpf_linker_file_opts { 1408 /* size of this struct, for forward/backward compatiblity */ 1409 size_t sz; 1410 }; 1411 #define bpf_linker_file_opts__last_field sz 1412 1413 struct bpf_linker; 1414 1415 LIBBPF_API struct bpf_linker *bpf_linker__new(const char *filename, struct bpf_linker_opts *opts); 1416 LIBBPF_API int bpf_linker__add_file(struct bpf_linker *linker, 1417 const char *filename, 1418 const struct bpf_linker_file_opts *opts); 1419 LIBBPF_API int bpf_linker__finalize(struct bpf_linker *linker); 1420 LIBBPF_API void bpf_linker__free(struct bpf_linker *linker); 1421 1422 /* 1423 * Custom handling of BPF program's SEC() definitions 1424 */ 1425 1426 struct bpf_prog_load_opts; /* defined in bpf.h */ 1427 1428 /* Called during bpf_object__open() for each recognized BPF program. Callback 1429 * can use various bpf_program__set_*() setters to adjust whatever properties 1430 * are necessary. 1431 */ 1432 typedef int (*libbpf_prog_setup_fn_t)(struct bpf_program *prog, long cookie); 1433 1434 /* Called right before libbpf performs bpf_prog_load() to load BPF program 1435 * into the kernel. Callback can adjust opts as necessary. 1436 */ 1437 typedef int (*libbpf_prog_prepare_load_fn_t)(struct bpf_program *prog, 1438 struct bpf_prog_load_opts *opts, long cookie); 1439 1440 /* Called during skeleton attach or through bpf_program__attach(). If 1441 * auto-attach is not supported, callback should return 0 and set link to 1442 * NULL (it's not considered an error during skeleton attach, but it will be 1443 * an error for bpf_program__attach() calls). On error, error should be 1444 * returned directly and link set to NULL. On success, return 0 and set link 1445 * to a valid struct bpf_link. 1446 */ 1447 typedef int (*libbpf_prog_attach_fn_t)(const struct bpf_program *prog, long cookie, 1448 struct bpf_link **link); 1449 1450 struct libbpf_prog_handler_opts { 1451 /* size of this struct, for forward/backward compatiblity */ 1452 size_t sz; 1453 /* User-provided value that is passed to prog_setup_fn, 1454 * prog_prepare_load_fn, and prog_attach_fn callbacks. Allows user to 1455 * register one set of callbacks for multiple SEC() definitions and 1456 * still be able to distinguish them, if necessary. For example, 1457 * libbpf itself is using this to pass necessary flags (e.g., 1458 * sleepable flag) to a common internal SEC() handler. 1459 */ 1460 long cookie; 1461 /* BPF program initialization callback (see libbpf_prog_setup_fn_t). 1462 * Callback is optional, pass NULL if it's not necessary. 1463 */ 1464 libbpf_prog_setup_fn_t prog_setup_fn; 1465 /* BPF program loading callback (see libbpf_prog_prepare_load_fn_t). 1466 * Callback is optional, pass NULL if it's not necessary. 1467 */ 1468 libbpf_prog_prepare_load_fn_t prog_prepare_load_fn; 1469 /* BPF program attach callback (see libbpf_prog_attach_fn_t). 1470 * Callback is optional, pass NULL if it's not necessary. 1471 */ 1472 libbpf_prog_attach_fn_t prog_attach_fn; 1473 }; 1474 #define libbpf_prog_handler_opts__last_field prog_attach_fn 1475 1476 /** 1477 * @brief **libbpf_register_prog_handler()** registers a custom BPF program 1478 * SEC() handler. 1479 * @param sec section prefix for which custom handler is registered 1480 * @param prog_type BPF program type associated with specified section 1481 * @param exp_attach_type Expected BPF attach type associated with specified section 1482 * @param opts optional cookie, callbacks, and other extra options 1483 * @return Non-negative handler ID is returned on success. This handler ID has 1484 * to be passed to *libbpf_unregister_prog_handler()* to unregister such 1485 * custom handler. Negative error code is returned on error. 1486 * 1487 * *sec* defines which SEC() definitions are handled by this custom handler 1488 * registration. *sec* can have few different forms: 1489 * - if *sec* is just a plain string (e.g., "abc"), it will match only 1490 * SEC("abc"). If BPF program specifies SEC("abc/whatever") it will result 1491 * in an error; 1492 * - if *sec* is of the form "abc/", proper SEC() form is 1493 * SEC("abc/something"), where acceptable "something" should be checked by 1494 * *prog_init_fn* callback, if there are additional restrictions; 1495 * - if *sec* is of the form "abc+", it will successfully match both 1496 * SEC("abc") and SEC("abc/whatever") forms; 1497 * - if *sec* is NULL, custom handler is registered for any BPF program that 1498 * doesn't match any of the registered (custom or libbpf's own) SEC() 1499 * handlers. There could be only one such generic custom handler registered 1500 * at any given time. 1501 * 1502 * All custom handlers (except the one with *sec* == NULL) are processed 1503 * before libbpf's own SEC() handlers. It is allowed to "override" libbpf's 1504 * SEC() handlers by registering custom ones for the same section prefix 1505 * (i.e., it's possible to have custom SEC("perf_event/LLC-load-misses") 1506 * handler). 1507 * 1508 * Note, like much of global libbpf APIs (e.g., libbpf_set_print(), 1509 * libbpf_set_strict_mode(), etc)) these APIs are not thread-safe. User needs 1510 * to ensure synchronization if there is a risk of running this API from 1511 * multiple threads simultaneously. 1512 */ 1513 LIBBPF_API int libbpf_register_prog_handler(const char *sec, 1514 enum bpf_prog_type prog_type, 1515 enum bpf_attach_type exp_attach_type, 1516 const struct libbpf_prog_handler_opts *opts); 1517 /** 1518 * @brief *libbpf_unregister_prog_handler()* unregisters previously registered 1519 * custom BPF program SEC() handler. 1520 * @param handler_id handler ID returned by *libbpf_register_prog_handler()* 1521 * after successful registration 1522 * @return 0 on success, negative error code if handler isn't found 1523 * 1524 * Note, like much of global libbpf APIs (e.g., libbpf_set_print(), 1525 * libbpf_set_strict_mode(), etc)) these APIs are not thread-safe. User needs 1526 * to ensure synchronization if there is a risk of running this API from 1527 * multiple threads simultaneously. 1528 */ 1529 LIBBPF_API int libbpf_unregister_prog_handler(int handler_id); 1530 1531 #ifdef __cplusplus 1532 } /* extern "C" */ 1533 #endif 1534 1535 #endif /* __LIBBPF_LIBBPF_H */ 1536