summaryrefslogtreecommitdiff
path: root/tools/lib/bpf/libbpf.h
blob: 8b9bc5e90c2b8b32556147cd34c9b37710d63ef1 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
756
757
758
759
760
761
762
763
764
765
766
767
768
769
770
771
772
773
774
775
776
777
778
779
780
781
782
783
784
785
786
787
788
789
790
791
792
793
794
795
796
797
798
799
800
801
802
803
804
805
806
807
808
809
810
811
812
813
814
815
816
817
818
819
820
821
822
823
824
825
826
827
828
829
830
831
832
833
834
835
836
837
838
839
840
841
842
843
844
845
846
847
848
849
850
851
852
853
854
855
856
857
858
859
860
861
862
863
864
865
866
867
868
869
870
871
872
873
874
875
876
877
878
879
880
881
882
883
884
885
886
887
888
889
890
891
892
893
894
895
896
897
898
899
900
901
902
903
904
905
906
907
908
909
910
911
912
913
914
915
916
917
918
919
920
921
922
923
924
925
926
927
928
929
930
931
932
933
934
935
936
937
938
939
940
941
942
943
944
945
946
947
948
949
950
951
952
953
954
955
956
957
958
959
960
961
962
963
964
965
966
967
968
969
970
971
972
973
974
975
976
977
978
979
980
981
982
983
984
985
986
987
988
989
990
991
992
993
994
995
996
997
998
999
1000
1001
1002
1003
1004
1005
1006
1007
1008
1009
1010
1011
1012
1013
1014
1015
1016
1017
1018
1019
1020
1021
1022
1023
1024
1025
1026
1027
1028
1029
1030
1031
1032
1033
1034
1035
1036
1037
1038
1039
1040
1041
1042
1043
1044
1045
1046
1047
1048
1049
1050
1051
1052
1053
1054
1055
1056
1057
1058
1059
1060
1061
1062
1063
1064
1065
1066
1067
1068
1069
1070
1071
1072
1073
1074
1075
1076
1077
1078
1079
1080
1081
1082
1083
1084
1085
1086
1087
1088
1089
1090
1091
1092
1093
1094
1095
1096
1097
1098
1099
1100
1101
1102
1103
1104
1105
1106
1107
1108
1109
1110
1111
1112
1113
1114
1115
1116
1117
1118
1119
1120
1121
1122
1123
1124
1125
1126
1127
1128
1129
1130
1131
1132
1133
1134
1135
1136
1137
1138
1139
1140
1141
1142
1143
1144
1145
1146
1147
1148
1149
1150
1151
1152
1153
1154
1155
1156
1157
1158
1159
1160
1161
1162
1163
1164
1165
1166
1167
1168
1169
1170
1171
1172
1173
1174
1175
1176
1177
1178
1179
1180
1181
1182
1183
1184
1185
1186
1187
1188
1189
1190
1191
1192
1193
1194
1195
1196
1197
1198
1199
1200
1201
1202
1203
1204
1205
1206
1207
1208
1209
1210
1211
1212
1213
1214
1215
1216
1217
1218
1219
1220
1221
1222
1223
1224
1225
1226
1227
1228
1229
1230
1231
1232
1233
1234
1235
1236
1237
1238
1239
1240
1241
1242
1243
1244
1245
1246
1247
1248
1249
1250
1251
1252
1253
1254
1255
1256
1257
1258
1259
1260
1261
1262
1263
1264
1265
1266
1267
1268
1269
1270
1271
1272
/* SPDX-License-Identifier: (LGPL-2.1 OR BSD-2-Clause) */

/*
 * Common eBPF ELF object loading operations.
 *
 * Copyright (C) 2013-2015 Alexei Starovoitov <ast@kernel.org>
 * Copyright (C) 2015 Wang Nan <wangnan0@huawei.com>
 * Copyright (C) 2015 Huawei Inc.
 */
#ifndef __LIBBPF_LIBBPF_H
#define __LIBBPF_LIBBPF_H

#include <stdarg.h>
#include <stdio.h>
#include <stdint.h>
#include <stdbool.h>
#include <sys/types.h>  // for size_t
#include <linux/bpf.h>

#include "libbpf_common.h"
#include "libbpf_legacy.h"

#ifdef __cplusplus
extern "C" {
#endif

LIBBPF_API __u32 libbpf_major_version(void);
LIBBPF_API __u32 libbpf_minor_version(void);
LIBBPF_API const char *libbpf_version_string(void);

enum libbpf_errno {
	__LIBBPF_ERRNO__START = 4000,

	/* Something wrong in libelf */
	LIBBPF_ERRNO__LIBELF = __LIBBPF_ERRNO__START,
	LIBBPF_ERRNO__FORMAT,	/* BPF object format invalid */
	LIBBPF_ERRNO__KVERSION,	/* Incorrect or no 'version' section */
	LIBBPF_ERRNO__ENDIAN,	/* Endian mismatch */
	LIBBPF_ERRNO__INTERNAL,	/* Internal error in libbpf */
	LIBBPF_ERRNO__RELOC,	/* Relocation failed */
	LIBBPF_ERRNO__LOAD,	/* Load program failure for unknown reason */
	LIBBPF_ERRNO__VERIFY,	/* Kernel verifier blocks program loading */
	LIBBPF_ERRNO__PROG2BIG,	/* Program too big */
	LIBBPF_ERRNO__KVER,	/* Incorrect kernel version */
	LIBBPF_ERRNO__PROGTYPE,	/* Kernel doesn't support this program type */
	LIBBPF_ERRNO__WRNGPID,	/* Wrong pid in netlink message */
	LIBBPF_ERRNO__INVSEQ,	/* Invalid netlink sequence */
	LIBBPF_ERRNO__NLPARSE,	/* netlink parsing error */
	__LIBBPF_ERRNO__END,
};

LIBBPF_API int libbpf_strerror(int err, char *buf, size_t size);

enum libbpf_print_level {
        LIBBPF_WARN,
        LIBBPF_INFO,
        LIBBPF_DEBUG,
};

typedef int (*libbpf_print_fn_t)(enum libbpf_print_level level,
				 const char *, va_list ap);

LIBBPF_API libbpf_print_fn_t libbpf_set_print(libbpf_print_fn_t fn);

/* Hide internal to user */
struct bpf_object;

struct bpf_object_open_attr {
	const char *file;
	enum bpf_prog_type prog_type;
};

struct bpf_object_open_opts {
	/* size of this struct, for forward/backward compatiblity */
	size_t sz;
	/* object name override, if provided:
	 * - for object open from file, this will override setting object
	 *   name from file path's base name;
	 * - for object open from memory buffer, this will specify an object
	 *   name and will override default "<addr>-<buf-size>" name;
	 */
	const char *object_name;
	/* parse map definitions non-strictly, allowing extra attributes/data */
	bool relaxed_maps;
	/* DEPRECATED: handle CO-RE relocations non-strictly, allowing failures.
	 * Value is ignored. Relocations always are processed non-strictly.
	 * Non-relocatable instructions are replaced with invalid ones to
	 * prevent accidental errors.
	 * */
	LIBBPF_DEPRECATED_SINCE(0, 6, "field has no effect")
	bool relaxed_core_relocs;
	/* maps that set the 'pinning' attribute in their definition will have
	 * their pin_path attribute set to a file in this directory, and be
	 * auto-pinned to that path on load; defaults to "/sys/fs/bpf".
	 */
	const char *pin_root_path;

	LIBBPF_DEPRECATED_SINCE(0, 7, "use bpf_program__set_attach_target() on each individual bpf_program")
	__u32 attach_prog_fd;
	/* Additional kernel config content that augments and overrides
	 * system Kconfig for CONFIG_xxx externs.
	 */
	const char *kconfig;
	/* Path to the custom BTF to be used for BPF CO-RE relocations.
	 * This custom BTF completely replaces the use of vmlinux BTF
	 * for the purpose of CO-RE relocations.
	 * NOTE: any other BPF feature (e.g., fentry/fexit programs,
	 * struct_ops, etc) will need actual kernel BTF at /sys/kernel/btf/vmlinux.
	 */
	const char *btf_custom_path;
	/* Pointer to a buffer for storing kernel logs for applicable BPF
	 * commands. Valid kernel_log_size has to be specified as well and are
	 * passed-through to bpf() syscall. Keep in mind that kernel might
	 * fail operation with -ENOSPC error if provided buffer is too small
	 * to contain entire log output.
	 * See the comment below for kernel_log_level for interaction between
	 * log_buf and log_level settings.
	 *
	 * If specified, this log buffer will be passed for:
	 *   - each BPF progral load (BPF_PROG_LOAD) attempt, unless overriden
	 *     with bpf_program__set_log() on per-program level, to get
	 *     BPF verifier log output.
	 *   - during BPF object's BTF load into kernel (BPF_BTF_LOAD) to get
	 *     BTF sanity checking log.
	 *
	 * Each BPF command (BPF_BTF_LOAD or BPF_PROG_LOAD) will overwrite
	 * previous contents, so if you need more fine-grained control, set
	 * per-program buffer with bpf_program__set_log_buf() to preserve each
	 * individual program's verification log. Keep using kernel_log_buf
	 * for BTF verification log, if necessary.
	 */
	char *kernel_log_buf;
	size_t kernel_log_size;
	/*
	 * Log level can be set independently from log buffer. Log_level=0
	 * means that libbpf will attempt loading BTF or program without any
	 * logging requested, but will retry with either its own or custom log
	 * buffer, if provided, and log_level=1 on any error.
	 * And vice versa, setting log_level>0 will request BTF or prog
	 * loading with verbose log from the first attempt (and as such also
	 * for successfully loaded BTF or program), and the actual log buffer
	 * could be either libbpf's own auto-allocated log buffer, if
	 * kernel_log_buffer is NULL, or user-provided custom kernel_log_buf.
	 * If user didn't provide custom log buffer, libbpf will emit captured
	 * logs through its print callback.
	 */
	__u32 kernel_log_level;

	size_t :0;
};
#define bpf_object_open_opts__last_field kernel_log_level

LIBBPF_API struct bpf_object *bpf_object__open(const char *path);

/**
 * @brief **bpf_object__open_file()** creates a bpf_object by opening
 * the BPF ELF object file pointed to by the passed path and loading it
 * into memory.
 * @param path BPF object file path
 * @param opts options for how to load the bpf object, this parameter is
 * optional and can be set to NULL
 * @return pointer to the new bpf_object; or NULL is returned on error,
 * error code is stored in errno
 */
LIBBPF_API struct bpf_object *
bpf_object__open_file(const char *path, const struct bpf_object_open_opts *opts);

/**
 * @brief **bpf_object__open_mem()** creates a bpf_object by reading
 * the BPF objects raw bytes from a memory buffer containing a valid
 * BPF ELF object file.
 * @param obj_buf pointer to the buffer containing ELF file bytes
 * @param obj_buf_sz number of bytes in the buffer
 * @param opts options for how to load the bpf object
 * @return pointer to the new bpf_object; or NULL is returned on error,
 * error code is stored in errno
 */
LIBBPF_API struct bpf_object *
bpf_object__open_mem(const void *obj_buf, size_t obj_buf_sz,
		     const struct bpf_object_open_opts *opts);

/* deprecated bpf_object__open variants */
LIBBPF_API struct bpf_object *
bpf_object__open_buffer(const void *obj_buf, size_t obj_buf_sz,
			const char *name);
LIBBPF_API struct bpf_object *
bpf_object__open_xattr(struct bpf_object_open_attr *attr);

enum libbpf_pin_type {
	LIBBPF_PIN_NONE,
	/* PIN_BY_NAME: pin maps by name (in /sys/fs/bpf by default) */
	LIBBPF_PIN_BY_NAME,
};

/* pin_maps and unpin_maps can both be called with a NULL path, in which case
 * they will use the pin_path attribute of each map (and ignore all maps that
 * don't have a pin_path set).
 */
LIBBPF_API int bpf_object__pin_maps(struct bpf_object *obj, const char *path);
LIBBPF_API int bpf_object__unpin_maps(struct bpf_object *obj,
				      const char *path);
LIBBPF_API int bpf_object__pin_programs(struct bpf_object *obj,
					const char *path);
LIBBPF_API int bpf_object__unpin_programs(struct bpf_object *obj,
					  const char *path);
LIBBPF_API int bpf_object__pin(struct bpf_object *object, const char *path);
LIBBPF_API void bpf_object__close(struct bpf_object *object);

struct bpf_object_load_attr {
	struct bpf_object *obj;
	int log_level;
	const char *target_btf_path;
};

/* Load/unload object into/from kernel */
LIBBPF_API int bpf_object__load(struct bpf_object *obj);
LIBBPF_DEPRECATED_SINCE(0, 8, "use bpf_object__load() instead")
LIBBPF_API int bpf_object__load_xattr(struct bpf_object_load_attr *attr);
LIBBPF_DEPRECATED_SINCE(0, 6, "bpf_object__unload() is deprecated, use bpf_object__close() instead")
LIBBPF_API int bpf_object__unload(struct bpf_object *obj);

LIBBPF_API const char *bpf_object__name(const struct bpf_object *obj);
LIBBPF_API unsigned int bpf_object__kversion(const struct bpf_object *obj);
LIBBPF_API int bpf_object__set_kversion(struct bpf_object *obj, __u32 kern_version);

struct btf;
LIBBPF_API struct btf *bpf_object__btf(const struct bpf_object *obj);
LIBBPF_API int bpf_object__btf_fd(const struct bpf_object *obj);

LIBBPF_DEPRECATED_SINCE(0, 7, "use bpf_object__find_program_by_name() instead")
LIBBPF_API struct bpf_program *
bpf_object__find_program_by_title(const struct bpf_object *obj,
				  const char *title);
LIBBPF_API struct bpf_program *
bpf_object__find_program_by_name(const struct bpf_object *obj,
				 const char *name);

LIBBPF_API LIBBPF_DEPRECATED_SINCE(0, 7, "track bpf_objects in application code instead")
struct bpf_object *bpf_object__next(struct bpf_object *prev);
#define bpf_object__for_each_safe(pos, tmp)			\
	for ((pos) = bpf_object__next(NULL),		\
		(tmp) = bpf_object__next(pos);		\
	     (pos) != NULL;				\
	     (pos) = (tmp), (tmp) = bpf_object__next(tmp))

typedef void (*bpf_object_clear_priv_t)(struct bpf_object *, void *);
LIBBPF_API int bpf_object__set_priv(struct bpf_object *obj, void *priv,
				    bpf_object_clear_priv_t clear_priv);
LIBBPF_API void *bpf_object__priv(const struct bpf_object *prog);

LIBBPF_API int
libbpf_prog_type_by_name(const char *name, enum bpf_prog_type *prog_type,
			 enum bpf_attach_type *expected_attach_type);
LIBBPF_API int libbpf_attach_type_by_name(const char *name,
					  enum bpf_attach_type *attach_type);
LIBBPF_API int libbpf_find_vmlinux_btf_id(const char *name,
					  enum bpf_attach_type attach_type);

/* Accessors of bpf_program */
struct bpf_program;
LIBBPF_API LIBBPF_DEPRECATED_SINCE(0, 7, "use bpf_object__next_program() instead")
struct bpf_program *bpf_program__next(struct bpf_program *prog,
				      const struct bpf_object *obj);
LIBBPF_API struct bpf_program *
bpf_object__next_program(const struct bpf_object *obj, struct bpf_program *prog);

#define bpf_object__for_each_program(pos, obj)			\
	for ((pos) = bpf_object__next_program((obj), NULL);	\
	     (pos) != NULL;					\
	     (pos) = bpf_object__next_program((obj), (pos)))

LIBBPF_API LIBBPF_DEPRECATED_SINCE(0, 7, "use bpf_object__prev_program() instead")
struct bpf_program *bpf_program__prev(struct bpf_program *prog,
				      const struct bpf_object *obj);
LIBBPF_API struct bpf_program *
bpf_object__prev_program(const struct bpf_object *obj, struct bpf_program *prog);

typedef void (*bpf_program_clear_priv_t)(struct bpf_program *, void *);

LIBBPF_API int bpf_program__set_priv(struct bpf_program *prog, void *priv,
				     bpf_program_clear_priv_t clear_priv);

LIBBPF_API void *bpf_program__priv(const struct bpf_program *prog);
LIBBPF_API void bpf_program__set_ifindex(struct bpf_program *prog,
					 __u32 ifindex);

LIBBPF_API const char *bpf_program__name(const struct bpf_program *prog);
LIBBPF_API const char *bpf_program__section_name(const struct bpf_program *prog);
LIBBPF_API LIBBPF_DEPRECATED("BPF program title is confusing term; please use bpf_program__section_name() instead")
const char *bpf_program__title(const struct bpf_program *prog, bool needs_copy);
LIBBPF_API bool bpf_program__autoload(const struct bpf_program *prog);
LIBBPF_API int bpf_program__set_autoload(struct bpf_program *prog, bool autoload);

/* returns program size in bytes */
LIBBPF_DEPRECATED_SINCE(0, 7, "use bpf_program__insn_cnt() instead")
LIBBPF_API size_t bpf_program__size(const struct bpf_program *prog);

struct bpf_insn;

/**
 * @brief **bpf_program__insns()** gives read-only access to BPF program's
 * underlying BPF instructions.
 * @param prog BPF program for which to return instructions
 * @return a pointer to an array of BPF instructions that belong to the
 * specified BPF program
 *
 * Returned pointer is always valid and not NULL. Number of `struct bpf_insn`
 * pointed to can be fetched using **bpf_program__insn_cnt()** API.
 *
 * Keep in mind, libbpf can modify and append/delete BPF program's
 * instructions as it processes BPF object file and prepares everything for
 * uploading into the kernel. So depending on the point in BPF object
 * lifetime, **bpf_program__insns()** can return different sets of
 * instructions. As an example, during BPF object load phase BPF program
 * instructions will be CO-RE-relocated, BPF subprograms instructions will be
 * appended, ldimm64 instructions will have FDs embedded, etc. So instructions
 * returned before **bpf_object__load()** and after it might be quite
 * different.
 */
LIBBPF_API const struct bpf_insn *bpf_program__insns(const struct bpf_program *prog);
/**
 * @brief **bpf_program__insn_cnt()** returns number of `struct bpf_insn`'s
 * that form specified BPF program.
 * @param prog BPF program for which to return number of BPF instructions
 *
 * See **bpf_program__insns()** documentation for notes on how libbpf can
 * change instructions and their count during different phases of
 * **bpf_object** lifetime.
 */
LIBBPF_API size_t bpf_program__insn_cnt(const struct bpf_program *prog);

LIBBPF_DEPRECATED_SINCE(0, 6, "use bpf_object__load() instead")
LIBBPF_API int bpf_program__load(struct bpf_program *prog, const char *license, __u32 kern_version);
LIBBPF_API int bpf_program__fd(const struct bpf_program *prog);
LIBBPF_DEPRECATED_SINCE(0, 7, "multi-instance bpf_program support is deprecated")
LIBBPF_API int bpf_program__pin_instance(struct bpf_program *prog,
					 const char *path,
					 int instance);
LIBBPF_DEPRECATED_SINCE(0, 7, "multi-instance bpf_program support is deprecated")
LIBBPF_API int bpf_program__unpin_instance(struct bpf_program *prog,
					   const char *path,
					   int instance);

/**
 * @brief **bpf_program__pin()** pins the BPF program to a file
 * in the BPF FS specified by a path. This increments the programs
 * reference count, allowing it to stay loaded after the process
 * which loaded it has exited.
 *
 * @param prog BPF program to pin, must already be loaded
 * @param path file path in a BPF file system
 * @return 0, on success; negative error code, otherwise
 */
LIBBPF_API int bpf_program__pin(struct bpf_program *prog, const char *path);

/**
 * @brief **bpf_program__unpin()** unpins the BPF program from a file
 * in the BPFFS specified by a path. This decrements the programs
 * reference count.
 *
 * The file pinning the BPF program can also be unlinked by a different
 * process in which case this function will return an error.
 *
 * @param prog BPF program to unpin
 * @param path file path to the pin in a BPF file system
 * @return 0, on success; negative error code, otherwise
 */
LIBBPF_API int bpf_program__unpin(struct bpf_program *prog, const char *path);
LIBBPF_API void bpf_program__unload(struct bpf_program *prog);

struct bpf_link;

LIBBPF_API struct bpf_link *bpf_link__open(const char *path);
LIBBPF_API int bpf_link__fd(const struct bpf_link *link);
LIBBPF_API const char *bpf_link__pin_path(const struct bpf_link *link);
LIBBPF_API int bpf_link__pin(struct bpf_link *link, const char *path);
LIBBPF_API int bpf_link__unpin(struct bpf_link *link);
LIBBPF_API int bpf_link__update_program(struct bpf_link *link,
					struct bpf_program *prog);
LIBBPF_API void bpf_link__disconnect(struct bpf_link *link);
LIBBPF_API int bpf_link__detach(struct bpf_link *link);
LIBBPF_API int bpf_link__destroy(struct bpf_link *link);

LIBBPF_API struct bpf_link *
bpf_program__attach(const struct bpf_program *prog);

struct bpf_perf_event_opts {
	/* size of this struct, for forward/backward compatiblity */
	size_t sz;
	/* custom user-provided value fetchable through bpf_get_attach_cookie() */
	__u64 bpf_cookie;
};
#define bpf_perf_event_opts__last_field bpf_cookie

LIBBPF_API struct bpf_link *
bpf_program__attach_perf_event(const struct bpf_program *prog, int pfd);

LIBBPF_API struct bpf_link *
bpf_program__attach_perf_event_opts(const struct bpf_program *prog, int pfd,
				    const struct bpf_perf_event_opts *opts);

struct bpf_kprobe_opts {
	/* size of this struct, for forward/backward compatiblity */
	size_t sz;
	/* custom user-provided value fetchable through bpf_get_attach_cookie() */
	__u64 bpf_cookie;
	/* function's offset to install kprobe to */
	size_t offset;
	/* kprobe is return probe */
	bool retprobe;
	size_t :0;
};
#define bpf_kprobe_opts__last_field retprobe

LIBBPF_API struct bpf_link *
bpf_program__attach_kprobe(const struct bpf_program *prog, bool retprobe,
			   const char *func_name);
LIBBPF_API struct bpf_link *
bpf_program__attach_kprobe_opts(const struct bpf_program *prog,
                                const char *func_name,
                                const struct bpf_kprobe_opts *opts);

struct bpf_uprobe_opts {
	/* size of this struct, for forward/backward compatiblity */
	size_t sz;
	/* offset of kernel reference counted USDT semaphore, added in
	 * a6ca88b241d5 ("trace_uprobe: support reference counter in fd-based uprobe")
	 */
	size_t ref_ctr_offset;
	/* custom user-provided value fetchable through bpf_get_attach_cookie() */
	__u64 bpf_cookie;
	/* uprobe is return probe, invoked at function return time */
	bool retprobe;
	size_t :0;
};
#define bpf_uprobe_opts__last_field retprobe

/**
 * @brief **bpf_program__attach_uprobe()** attaches a BPF program
 * to the userspace function which is found by binary path and
 * offset. You can optionally specify a particular proccess to attach
 * to. You can also optionally attach the program to the function
 * exit instead of entry.
 *
 * @param prog BPF program to attach
 * @param retprobe Attach to function exit
 * @param pid Process ID to attach the uprobe to, 0 for self (own process),
 * -1 for all processes
 * @param binary_path Path to binary that contains the function symbol
 * @param func_offset Offset within the binary of the function symbol
 * @return Reference to the newly created BPF link; or NULL is returned on error,
 * error code is stored in errno
 */
LIBBPF_API struct bpf_link *
bpf_program__attach_uprobe(const struct bpf_program *prog, bool retprobe,
			   pid_t pid, const char *binary_path,
			   size_t func_offset);

/**
 * @brief **bpf_program__attach_uprobe_opts()** is just like
 * bpf_program__attach_uprobe() except with a options struct
 * for various configurations.
 *
 * @param prog BPF program to attach
 * @param pid Process ID to attach the uprobe to, 0 for self (own process),
 * -1 for all processes
 * @param binary_path Path to binary that contains the function symbol
 * @param func_offset Offset within the binary of the function symbol
 * @param opts Options for altering program attachment
 * @return Reference to the newly created BPF link; or NULL is returned on error,
 * error code is stored in errno
 */
LIBBPF_API struct bpf_link *
bpf_program__attach_uprobe_opts(const struct bpf_program *prog, pid_t pid,
				const char *binary_path, size_t func_offset,
				const struct bpf_uprobe_opts *opts);

struct bpf_tracepoint_opts {
	/* size of this struct, for forward/backward compatiblity */
	size_t sz;
	/* custom user-provided value fetchable through bpf_get_attach_cookie() */
	__u64 bpf_cookie;
};
#define bpf_tracepoint_opts__last_field bpf_cookie

LIBBPF_API struct bpf_link *
bpf_program__attach_tracepoint(const struct bpf_program *prog,
			       const char *tp_category,
			       const char *tp_name);
LIBBPF_API struct bpf_link *
bpf_program__attach_tracepoint_opts(const struct bpf_program *prog,
				    const char *tp_category,
				    const char *tp_name,
				    const struct bpf_tracepoint_opts *opts);

LIBBPF_API struct bpf_link *
bpf_program__attach_raw_tracepoint(const struct bpf_program *prog,
				   const char *tp_name);
LIBBPF_API struct bpf_link *
bpf_program__attach_trace(const struct bpf_program *prog);
LIBBPF_API struct bpf_link *
bpf_program__attach_lsm(const struct bpf_program *prog);
LIBBPF_API struct bpf_link *
bpf_program__attach_cgroup(const struct bpf_program *prog, int cgroup_fd);
LIBBPF_API struct bpf_link *
bpf_program__attach_netns(const struct bpf_program *prog, int netns_fd);
LIBBPF_API struct bpf_link *
bpf_program__attach_xdp(const struct bpf_program *prog, int ifindex);
LIBBPF_API struct bpf_link *
bpf_program__attach_freplace(const struct bpf_program *prog,
			     int target_fd, const char *attach_func_name);

struct bpf_map;

LIBBPF_API struct bpf_link *bpf_map__attach_struct_ops(const struct bpf_map *map);

struct bpf_iter_attach_opts {
	size_t sz; /* size of this struct for forward/backward compatibility */
	union bpf_iter_link_info *link_info;
	__u32 link_info_len;
};
#define bpf_iter_attach_opts__last_field link_info_len

LIBBPF_API struct bpf_link *
bpf_program__attach_iter(const struct bpf_program *prog,
			 const struct bpf_iter_attach_opts *opts);

/*
 * Libbpf allows callers to adjust BPF programs before being loaded
 * into kernel. One program in an object file can be transformed into
 * multiple variants to be attached to different hooks.
 *
 * bpf_program_prep_t, bpf_program__set_prep and bpf_program__nth_fd
 * form an API for this purpose.
 *
 * - bpf_program_prep_t:
 *   Defines a 'preprocessor', which is a caller defined function
 *   passed to libbpf through bpf_program__set_prep(), and will be
 *   called before program is loaded. The processor should adjust
 *   the program one time for each instance according to the instance id
 *   passed to it.
 *
 * - bpf_program__set_prep:
 *   Attaches a preprocessor to a BPF program. The number of instances
 *   that should be created is also passed through this function.
 *
 * - bpf_program__nth_fd:
 *   After the program is loaded, get resulting FD of a given instance
 *   of the BPF program.
 *
 * If bpf_program__set_prep() is not used, the program would be loaded
 * without adjustment during bpf_object__load(). The program has only
 * one instance. In this case bpf_program__fd(prog) is equal to
 * bpf_program__nth_fd(prog, 0).
 */
struct bpf_prog_prep_result {
	/*
	 * If not NULL, load new instruction array.
	 * If set to NULL, don't load this instance.
	 */
	struct bpf_insn *new_insn_ptr;
	int new_insn_cnt;

	/* If not NULL, result FD is written to it. */
	int *pfd;
};

/*
 * Parameters of bpf_program_prep_t:
 *  - prog:	The bpf_program being loaded.
 *  - n:	Index of instance being generated.
 *  - insns:	BPF instructions array.
 *  - insns_cnt:Number of instructions in insns.
 *  - res:	Output parameter, result of transformation.
 *
 * Return value:
 *  - Zero:	pre-processing success.
 *  - Non-zero:	pre-processing error, stop loading.
 */
typedef int (*bpf_program_prep_t)(struct bpf_program *prog, int n,
				  struct bpf_insn *insns, int insns_cnt,
				  struct bpf_prog_prep_result *res);

LIBBPF_DEPRECATED_SINCE(0, 7, "use bpf_program__insns() for getting bpf_program instructions")
LIBBPF_API int bpf_program__set_prep(struct bpf_program *prog, int nr_instance,
				     bpf_program_prep_t prep);

LIBBPF_DEPRECATED_SINCE(0, 7, "multi-instance bpf_program support is deprecated")
LIBBPF_API int bpf_program__nth_fd(const struct bpf_program *prog, int n);

/*
 * Adjust type of BPF program. Default is kprobe.
 */
LIBBPF_API int bpf_program__set_socket_filter(struct bpf_program *prog);
LIBBPF_API int bpf_program__set_tracepoint(struct bpf_program *prog);
LIBBPF_API int bpf_program__set_raw_tracepoint(struct bpf_program *prog);
LIBBPF_API int bpf_program__set_kprobe(struct bpf_program *prog);
LIBBPF_API int bpf_program__set_lsm(struct bpf_program *prog);
LIBBPF_API int bpf_program__set_sched_cls(struct bpf_program *prog);
LIBBPF_API int bpf_program__set_sched_act(struct bpf_program *prog);
LIBBPF_API int bpf_program__set_xdp(struct bpf_program *prog);
LIBBPF_API int bpf_program__set_perf_event(struct bpf_program *prog);
LIBBPF_API int bpf_program__set_tracing(struct bpf_program *prog);
LIBBPF_API int bpf_program__set_struct_ops(struct bpf_program *prog);
LIBBPF_API int bpf_program__set_extension(struct bpf_program *prog);
LIBBPF_API int bpf_program__set_sk_lookup(struct bpf_program *prog);

LIBBPF_API enum bpf_prog_type bpf_program__get_type(const struct bpf_program *prog);
LIBBPF_API void bpf_program__set_type(struct bpf_program *prog,
				      enum bpf_prog_type type);

LIBBPF_API enum bpf_attach_type
bpf_program__get_expected_attach_type(const struct bpf_program *prog);
LIBBPF_API void
bpf_program__set_expected_attach_type(struct bpf_program *prog,
				      enum bpf_attach_type type);

LIBBPF_API __u32 bpf_program__flags(const struct bpf_program *prog);
LIBBPF_API int bpf_program__set_flags(struct bpf_program *prog, __u32 flags);

/* Per-program log level and log buffer getters/setters.
 * See bpf_object_open_opts comments regarding log_level and log_buf
 * interactions.
 */
LIBBPF_API __u32 bpf_program__log_level(const struct bpf_program *prog);
LIBBPF_API int bpf_program__set_log_level(struct bpf_program *prog, __u32 log_level);
LIBBPF_API const char *bpf_program__log_buf(const struct bpf_program *prog, size_t *log_size);
LIBBPF_API int bpf_program__set_log_buf(struct bpf_program *prog, char *log_buf, size_t log_size);

LIBBPF_API int
bpf_program__set_attach_target(struct bpf_program *prog, int attach_prog_fd,
			       const char *attach_func_name);

LIBBPF_API bool bpf_program__is_socket_filter(const struct bpf_program *prog);
LIBBPF_API bool bpf_program__is_tracepoint(const struct bpf_program *prog);
LIBBPF_API bool bpf_program__is_raw_tracepoint(const struct bpf_program *prog);
LIBBPF_API bool bpf_program__is_kprobe(const struct bpf_program *prog);
LIBBPF_API bool bpf_program__is_lsm(const struct bpf_program *prog);
LIBBPF_API bool bpf_program__is_sched_cls(const struct bpf_program *prog);
LIBBPF_API bool bpf_program__is_sched_act(const struct bpf_program *prog);
LIBBPF_API bool bpf_program__is_xdp(const struct bpf_program *prog);
LIBBPF_API bool bpf_program__is_perf_event(const struct bpf_program *prog);
LIBBPF_API bool bpf_program__is_tracing(const struct bpf_program *prog);
LIBBPF_API bool bpf_program__is_struct_ops(const struct bpf_program *prog);
LIBBPF_API bool bpf_program__is_extension(const struct bpf_program *prog);
LIBBPF_API bool bpf_program__is_sk_lookup(const struct bpf_program *prog);

/*
 * No need for __attribute__((packed)), all members of 'bpf_map_def'
 * are all aligned.  In addition, using __attribute__((packed))
 * would trigger a -Wpacked warning message, and lead to an error
 * if -Werror is set.
 */
struct bpf_map_def {
	unsigned int type;
	unsigned int key_size;
	unsigned int value_size;
	unsigned int max_entries;
	unsigned int map_flags;
};

/**
 * @brief **bpf_object__find_map_by_name()** returns BPF map of
 * the given name, if it exists within the passed BPF object
 * @param obj BPF object
 * @param name name of the BPF map
 * @return BPF map instance, if such map exists within the BPF object;
 * or NULL otherwise.
 */
LIBBPF_API struct bpf_map *
bpf_object__find_map_by_name(const struct bpf_object *obj, const char *name);

LIBBPF_API int
bpf_object__find_map_fd_by_name(const struct bpf_object *obj, const char *name);

/*
 * Get bpf_map through the offset of corresponding struct bpf_map_def
 * in the BPF object file.
 */
LIBBPF_API LIBBPF_DEPRECATED_SINCE(0, 8, "use bpf_object__find_map_by_name() instead")
struct bpf_map *
bpf_object__find_map_by_offset(struct bpf_object *obj, size_t offset);

LIBBPF_API LIBBPF_DEPRECATED_SINCE(0, 7, "use bpf_object__next_map() instead")
struct bpf_map *bpf_map__next(const struct bpf_map *map, const struct bpf_object *obj);
LIBBPF_API struct bpf_map *
bpf_object__next_map(const struct bpf_object *obj, const struct bpf_map *map);

#define bpf_object__for_each_map(pos, obj)		\
	for ((pos) = bpf_object__next_map((obj), NULL);	\
	     (pos) != NULL;				\
	     (pos) = bpf_object__next_map((obj), (pos)))
#define bpf_map__for_each bpf_object__for_each_map

LIBBPF_API LIBBPF_DEPRECATED_SINCE(0, 7, "use bpf_object__prev_map() instead")
struct bpf_map *bpf_map__prev(const struct bpf_map *map, const struct bpf_object *obj);
LIBBPF_API struct bpf_map *
bpf_object__prev_map(const struct bpf_object *obj, const struct bpf_map *map);

/**
 * @brief **bpf_map__fd()** gets the file descriptor of the passed
 * BPF map
 * @param map the BPF map instance
 * @return the file descriptor; or -EINVAL in case of an error
 */
LIBBPF_API int bpf_map__fd(const struct bpf_map *map);
LIBBPF_API int bpf_map__reuse_fd(struct bpf_map *map, int fd);
/* get map definition */
LIBBPF_API const struct bpf_map_def *bpf_map__def(const struct bpf_map *map);
/* get map name */
LIBBPF_API const char *bpf_map__name(const struct bpf_map *map);
/* get/set map type */
LIBBPF_API enum bpf_map_type bpf_map__type(const struct bpf_map *map);
LIBBPF_API int bpf_map__set_type(struct bpf_map *map, enum bpf_map_type type);
/* get/set map size (max_entries) */
LIBBPF_API __u32 bpf_map__max_entries(const struct bpf_map *map);
LIBBPF_API int bpf_map__set_max_entries(struct bpf_map *map, __u32 max_entries);
LIBBPF_API int bpf_map__resize(struct bpf_map *map, __u32 max_entries);
/* get/set map flags */
LIBBPF_API __u32 bpf_map__map_flags(const struct bpf_map *map);
LIBBPF_API int bpf_map__set_map_flags(struct bpf_map *map, __u32 flags);
/* get/set map NUMA node */
LIBBPF_API __u32 bpf_map__numa_node(const struct bpf_map *map);
LIBBPF_API int bpf_map__set_numa_node(struct bpf_map *map, __u32 numa_node);
/* get/set map key size */
LIBBPF_API __u32 bpf_map__key_size(const struct bpf_map *map);
LIBBPF_API int bpf_map__set_key_size(struct bpf_map *map, __u32 size);
/* get/set map value size */
LIBBPF_API __u32 bpf_map__value_size(const struct bpf_map *map);
LIBBPF_API int bpf_map__set_value_size(struct bpf_map *map, __u32 size);
/* get map key/value BTF type IDs */
LIBBPF_API __u32 bpf_map__btf_key_type_id(const struct bpf_map *map);
LIBBPF_API __u32 bpf_map__btf_value_type_id(const struct bpf_map *map);
/* get/set map if_index */
LIBBPF_API __u32 bpf_map__ifindex(const struct bpf_map *map);
LIBBPF_API int bpf_map__set_ifindex(struct bpf_map *map, __u32 ifindex);
/* get/set map map_extra flags */
LIBBPF_API __u64 bpf_map__map_extra(const struct bpf_map *map);
LIBBPF_API int bpf_map__set_map_extra(struct bpf_map *map, __u64 map_extra);

typedef void (*bpf_map_clear_priv_t)(struct bpf_map *, void *);
LIBBPF_API int bpf_map__set_priv(struct bpf_map *map, void *priv,
				 bpf_map_clear_priv_t clear_priv);
LIBBPF_API void *bpf_map__priv(const struct bpf_map *map);
LIBBPF_API int bpf_map__set_initial_value(struct bpf_map *map,
					  const void *data, size_t size);
LIBBPF_API const void *bpf_map__initial_value(struct bpf_map *map, size_t *psize);
LIBBPF_DEPRECATED_SINCE(0, 8, "use bpf_map__type() instead")
LIBBPF_API bool bpf_map__is_offload_neutral(const struct bpf_map *map);

/**
 * @brief **bpf_map__is_internal()** tells the caller whether or not the
 * passed map is a special map created by libbpf automatically for things like
 * global variables, __ksym externs, Kconfig values, etc
 * @param map the bpf_map
 * @return true, if the map is an internal map; false, otherwise
 */
LIBBPF_API bool bpf_map__is_internal(const struct bpf_map *map);
LIBBPF_API int bpf_map__set_pin_path(struct bpf_map *map, const char *path);
LIBBPF_API const char *bpf_map__get_pin_path(const struct bpf_map *map);
LIBBPF_API const char *bpf_map__pin_path(const struct bpf_map *map);
LIBBPF_API bool bpf_map__is_pinned(const struct bpf_map *map);
LIBBPF_API int bpf_map__pin(struct bpf_map *map, const char *path);
LIBBPF_API int bpf_map__unpin(struct bpf_map *map, const char *path);

LIBBPF_API int bpf_map__set_inner_map_fd(struct bpf_map *map, int fd);
LIBBPF_API struct bpf_map *bpf_map__inner_map(struct bpf_map *map);

/**
 * @brief **libbpf_get_error()** extracts the error code from the passed
 * pointer
 * @param ptr pointer returned from libbpf API function
 * @return error code; or 0 if no error occured
 *
 * Many libbpf API functions which return pointers have logic to encode error
 * codes as pointers, and do not return NULL. Meaning **libbpf_get_error()**
 * should be used on the return value from these functions immediately after
 * calling the API function, with no intervening calls that could clobber the
 * `errno` variable. Consult the individual functions documentation to verify
 * if this logic applies should be used.
 *
 * For these API functions, if `libbpf_set_strict_mode(LIBBPF_STRICT_CLEAN_PTRS)`
 * is enabled, NULL is returned on error instead.
 *
 * If ptr is NULL, then errno should be already set by the failing
 * API, because libbpf never returns NULL on success and it now always
 * sets errno on error.
 *
 * Example usage:
 *
 *   struct perf_buffer *pb;
 *
 *   pb = perf_buffer__new(bpf_map__fd(obj->maps.events), PERF_BUFFER_PAGES, &opts);
 *   err = libbpf_get_error(pb);
 *   if (err) {
 *	  pb = NULL;
 *	  fprintf(stderr, "failed to open perf buffer: %d\n", err);
 *	  goto cleanup;
 *   }
 */
LIBBPF_API long libbpf_get_error(const void *ptr);

struct bpf_prog_load_attr {
	const char *file;
	enum bpf_prog_type prog_type;
	enum bpf_attach_type expected_attach_type;
	int ifindex;
	int log_level;
	int prog_flags;
};

LIBBPF_DEPRECATED_SINCE(0, 8, "use bpf_object__open() and bpf_object__load() instead")
LIBBPF_API int bpf_prog_load_xattr(const struct bpf_prog_load_attr *attr,
				   struct bpf_object **pobj, int *prog_fd);
LIBBPF_DEPRECATED_SINCE(0, 7, "use bpf_object__open() and bpf_object__load() instead")
LIBBPF_API int bpf_prog_load_deprecated(const char *file, enum bpf_prog_type type,
					struct bpf_object **pobj, int *prog_fd);

/* XDP related API */
struct xdp_link_info {
	__u32 prog_id;
	__u32 drv_prog_id;
	__u32 hw_prog_id;
	__u32 skb_prog_id;
	__u8 attach_mode;
};

struct bpf_xdp_set_link_opts {
	size_t sz;
	int old_fd;
	size_t :0;
};
#define bpf_xdp_set_link_opts__last_field old_fd

LIBBPF_API int bpf_set_link_xdp_fd(int ifindex, int fd, __u32 flags);
LIBBPF_API int bpf_set_link_xdp_fd_opts(int ifindex, int fd, __u32 flags,
					const struct bpf_xdp_set_link_opts *opts);
LIBBPF_API int bpf_get_link_xdp_id(int ifindex, __u32 *prog_id, __u32 flags);
LIBBPF_API int bpf_get_link_xdp_info(int ifindex, struct xdp_link_info *info,
				     size_t info_size, __u32 flags);

/* TC related API */
enum bpf_tc_attach_point {
	BPF_TC_INGRESS = 1 << 0,
	BPF_TC_EGRESS  = 1 << 1,
	BPF_TC_CUSTOM  = 1 << 2,
};

#define BPF_TC_PARENT(a, b) 	\
	((((a) << 16) & 0xFFFF0000U) | ((b) & 0x0000FFFFU))

enum bpf_tc_flags {
	BPF_TC_F_REPLACE = 1 << 0,
};

struct bpf_tc_hook {
	size_t sz;
	int ifindex;
	enum bpf_tc_attach_point attach_point;
	__u32 parent;
	size_t :0;
};
#define bpf_tc_hook__last_field parent

struct bpf_tc_opts {
	size_t sz;
	int prog_fd;
	__u32 flags;
	__u32 prog_id;
	__u32 handle;
	__u32 priority;
	size_t :0;
};
#define bpf_tc_opts__last_field priority

LIBBPF_API int bpf_tc_hook_create(struct bpf_tc_hook *hook);
LIBBPF_API int bpf_tc_hook_destroy(struct bpf_tc_hook *hook);
LIBBPF_API int bpf_tc_attach(const struct bpf_tc_hook *hook,
			     struct bpf_tc_opts *opts);
LIBBPF_API int bpf_tc_detach(const struct bpf_tc_hook *hook,
			     const struct bpf_tc_opts *opts);
LIBBPF_API int bpf_tc_query(const struct bpf_tc_hook *hook,
			    struct bpf_tc_opts *opts);

/* Ring buffer APIs */
struct ring_buffer;

typedef int (*ring_buffer_sample_fn)(void *ctx, void *data, size_t size);

struct ring_buffer_opts {
	size_t sz; /* size of this struct, for forward/backward compatiblity */
};

#define ring_buffer_opts__last_field sz

LIBBPF_API struct ring_buffer *
ring_buffer__new(int map_fd, ring_buffer_sample_fn sample_cb, void *ctx,
		 const struct ring_buffer_opts *opts);
LIBBPF_API void ring_buffer__free(struct ring_buffer *rb);
LIBBPF_API int ring_buffer__add(struct ring_buffer *rb, int map_fd,
				ring_buffer_sample_fn sample_cb, void *ctx);
LIBBPF_API int ring_buffer__poll(struct ring_buffer *rb, int timeout_ms);
LIBBPF_API int ring_buffer__consume(struct ring_buffer *rb);
LIBBPF_API int ring_buffer__epoll_fd(const struct ring_buffer *rb);

/* Perf buffer APIs */
struct perf_buffer;

typedef void (*perf_buffer_sample_fn)(void *ctx, int cpu,
				      void *data, __u32 size);
typedef void (*perf_buffer_lost_fn)(void *ctx, int cpu, __u64 cnt);

/* common use perf buffer options */
struct perf_buffer_opts {
	union {
		size_t sz;
		struct { /* DEPRECATED: will be removed in v1.0 */
			/* if specified, sample_cb is called for each sample */
			perf_buffer_sample_fn sample_cb;
			/* if specified, lost_cb is called for each batch of lost samples */
			perf_buffer_lost_fn lost_cb;
			/* ctx is provided to sample_cb and lost_cb */
			void *ctx;
		};
	};
};
#define perf_buffer_opts__last_field sz

/**
 * @brief **perf_buffer__new()** creates BPF perfbuf manager for a specified
 * BPF_PERF_EVENT_ARRAY map
 * @param map_fd FD of BPF_PERF_EVENT_ARRAY BPF map that will be used by BPF
 * code to send data over to user-space
 * @param page_cnt number of memory pages allocated for each per-CPU buffer
 * @param sample_cb function called on each received data record
 * @param lost_cb function called when record loss has occurred
 * @param ctx user-provided extra context passed into *sample_cb* and *lost_cb*
 * @return a new instance of struct perf_buffer on success, NULL on error with
 * *errno* containing an error code
 */
LIBBPF_API struct perf_buffer *
perf_buffer__new(int map_fd, size_t page_cnt,
		 perf_buffer_sample_fn sample_cb, perf_buffer_lost_fn lost_cb, void *ctx,
		 const struct perf_buffer_opts *opts);

LIBBPF_API struct perf_buffer *
perf_buffer__new_v0_6_0(int map_fd, size_t page_cnt,
			perf_buffer_sample_fn sample_cb, perf_buffer_lost_fn lost_cb, void *ctx,
			const struct perf_buffer_opts *opts);

LIBBPF_API LIBBPF_DEPRECATED_SINCE(0, 7, "use new variant of perf_buffer__new() instead")
struct perf_buffer *perf_buffer__new_deprecated(int map_fd, size_t page_cnt,
						const struct perf_buffer_opts *opts);

#define perf_buffer__new(...) ___libbpf_overload(___perf_buffer_new, __VA_ARGS__)
#define ___perf_buffer_new6(map_fd, page_cnt, sample_cb, lost_cb, ctx, opts) \
	perf_buffer__new(map_fd, page_cnt, sample_cb, lost_cb, ctx, opts)
#define ___perf_buffer_new3(map_fd, page_cnt, opts) \
	perf_buffer__new_deprecated(map_fd, page_cnt, opts)

enum bpf_perf_event_ret {
	LIBBPF_PERF_EVENT_DONE	= 0,
	LIBBPF_PERF_EVENT_ERROR	= -1,
	LIBBPF_PERF_EVENT_CONT	= -2,
};

struct perf_event_header;

typedef enum bpf_perf_event_ret
(*perf_buffer_event_fn)(void *ctx, int cpu, struct perf_event_header *event);

/* raw perf buffer options, giving most power and control */
struct perf_buffer_raw_opts {
	union {
		struct {
			size_t sz;
			long :0;
			long :0;
		};
		struct { /* DEPRECATED: will be removed in v1.0 */
			/* perf event attrs passed directly into perf_event_open() */
			struct perf_event_attr *attr;
			/* raw event callback */
			perf_buffer_event_fn event_cb;
			/* ctx is provided to event_cb */
			void *ctx;
		};
	};
	/* if cpu_cnt == 0, open all on all possible CPUs (up to the number of
	 * max_entries of given PERF_EVENT_ARRAY map)
	 */
	int cpu_cnt;
	/* if cpu_cnt > 0, cpus is an array of CPUs to open ring buffers on */
	int *cpus;
	/* if cpu_cnt > 0, map_keys specify map keys to set per-CPU FDs for */
	int *map_keys;
};
#define perf_buffer_raw_opts__last_field map_keys

LIBBPF_API struct perf_buffer *
perf_buffer__new_raw(int map_fd, size_t page_cnt, struct perf_event_attr *attr,
		     perf_buffer_event_fn event_cb, void *ctx,
		     const struct perf_buffer_raw_opts *opts);

LIBBPF_API struct perf_buffer *
perf_buffer__new_raw_v0_6_0(int map_fd, size_t page_cnt, struct perf_event_attr *attr,
			    perf_buffer_event_fn event_cb, void *ctx,
			    const struct perf_buffer_raw_opts *opts);

LIBBPF_API LIBBPF_DEPRECATED_SINCE(0, 7, "use new variant of perf_buffer__new_raw() instead")
struct perf_buffer *perf_buffer__new_raw_deprecated(int map_fd, size_t page_cnt,
						    const struct perf_buffer_raw_opts *opts);

#define perf_buffer__new_raw(...) ___libbpf_overload(___perf_buffer_new_raw, __VA_ARGS__)
#define ___perf_buffer_new_raw6(map_fd, page_cnt, attr, event_cb, ctx, opts) \
	perf_buffer__new_raw(map_fd, page_cnt, attr, event_cb, ctx, opts)
#define ___perf_buffer_new_raw3(map_fd, page_cnt, opts) \
	perf_buffer__new_raw_deprecated(map_fd, page_cnt, opts)

LIBBPF_API void perf_buffer__free(struct perf_buffer *pb);
LIBBPF_API int perf_buffer__epoll_fd(const struct perf_buffer *pb);
LIBBPF_API int perf_buffer__poll(struct perf_buffer *pb, int timeout_ms);
LIBBPF_API int perf_buffer__consume(struct perf_buffer *pb);
LIBBPF_API int perf_buffer__consume_buffer(struct perf_buffer *pb, size_t buf_idx);
LIBBPF_API size_t perf_buffer__buffer_cnt(const struct perf_buffer *pb);
LIBBPF_API int perf_buffer__buffer_fd(const struct perf_buffer *pb, size_t buf_idx);

typedef enum bpf_perf_event_ret
	(*bpf_perf_event_print_t)(struct perf_event_header *hdr,
				  void *private_data);
LIBBPF_DEPRECATED_SINCE(0, 8, "use perf_buffer__poll() or  perf_buffer__consume() instead")
LIBBPF_API enum bpf_perf_event_ret
bpf_perf_event_read_simple(void *mmap_mem, size_t mmap_size, size_t page_size,
			   void **copy_mem, size_t *copy_size,
			   bpf_perf_event_print_t fn, void *private_data);

struct bpf_prog_linfo;
struct bpf_prog_info;

LIBBPF_API void bpf_prog_linfo__free(struct bpf_prog_linfo *prog_linfo);
LIBBPF_API struct bpf_prog_linfo *
bpf_prog_linfo__new(const struct bpf_prog_info *info);
LIBBPF_API const struct bpf_line_info *
bpf_prog_linfo__lfind_addr_func(const struct bpf_prog_linfo *prog_linfo,
				__u64 addr, __u32 func_idx, __u32 nr_skip);
LIBBPF_API const struct bpf_line_info *
bpf_prog_linfo__lfind(const struct bpf_prog_linfo *prog_linfo,
		      __u32 insn_off, __u32 nr_skip);

/*
 * Probe for supported system features
 *
 * Note that running many of these probes in a short amount of time can cause
 * the kernel to reach the maximal size of lockable memory allowed for the
 * user, causing subsequent probes to fail. In this case, the caller may want
 * to adjust that limit with setrlimit().
 */
LIBBPF_DEPRECATED_SINCE(0, 8, "use libbpf_probe_bpf_prog_type() instead")
LIBBPF_API bool bpf_probe_prog_type(enum bpf_prog_type prog_type, __u32 ifindex);
LIBBPF_DEPRECATED_SINCE(0, 8, "use libbpf_probe_bpf_map_type() instead")
LIBBPF_API bool bpf_probe_map_type(enum bpf_map_type map_type, __u32 ifindex);
LIBBPF_DEPRECATED_SINCE(0, 8, "use libbpf_probe_bpf_helper() instead")
LIBBPF_API bool bpf_probe_helper(enum bpf_func_id id, enum bpf_prog_type prog_type, __u32 ifindex);
LIBBPF_DEPRECATED_SINCE(0, 8, "implement your own or use bpftool for feature detection")
LIBBPF_API bool bpf_probe_large_insn_limit(__u32 ifindex);

/**
 * @brief **libbpf_probe_bpf_prog_type()** detects if host kernel supports
 * BPF programs of a given type.
 * @param prog_type BPF program type to detect kernel support for
 * @param opts reserved for future extensibility, should be NULL
 * @return 1, if given program type is supported; 0, if given program type is
 * not supported; negative error code if feature detection failed or can't be
 * performed
 *
 * Make sure the process has required set of CAP_* permissions (or runs as
 * root) when performing feature checking.
 */
LIBBPF_API int libbpf_probe_bpf_prog_type(enum bpf_prog_type prog_type, const void *opts);
/**
 * @brief **libbpf_probe_bpf_map_type()** detects if host kernel supports
 * BPF maps of a given type.
 * @param map_type BPF map type to detect kernel support for
 * @param opts reserved for future extensibility, should be NULL
 * @return 1, if given map type is supported; 0, if given map type is
 * not supported; negative error code if feature detection failed or can't be
 * performed
 *
 * Make sure the process has required set of CAP_* permissions (or runs as
 * root) when performing feature checking.
 */
LIBBPF_API int libbpf_probe_bpf_map_type(enum bpf_map_type map_type, const void *opts);
/**
 * @brief **libbpf_probe_bpf_helper()** detects if host kernel supports the
 * use of a given BPF helper from specified BPF program type.
 * @param prog_type BPF program type used to check the support of BPF helper
 * @param helper_id BPF helper ID (enum bpf_func_id) to check support for
 * @param opts reserved for future extensibility, should be NULL
 * @return 1, if given combination of program type and helper is supported; 0,
 * if the combination is not supported; negative error code if feature
 * detection for provided input arguments failed or can't be performed
 *
 * Make sure the process has required set of CAP_* permissions (or runs as
 * root) when performing feature checking.
 */
LIBBPF_API int libbpf_probe_bpf_helper(enum bpf_prog_type prog_type,
				       enum bpf_func_id helper_id, const void *opts);

/*
 * Get bpf_prog_info in continuous memory
 *
 * struct bpf_prog_info has multiple arrays. The user has option to choose
 * arrays to fetch from kernel. The following APIs provide an uniform way to
 * fetch these data. All arrays in bpf_prog_info are stored in a single
 * continuous memory region. This makes it easy to store the info in a
 * file.
 *
 * Before writing bpf_prog_info_linear to files, it is necessary to
 * translate pointers in bpf_prog_info to offsets. Helper functions
 * bpf_program__bpil_addr_to_offs() and bpf_program__bpil_offs_to_addr()
 * are introduced to switch between pointers and offsets.
 *
 * Examples:
 *   # To fetch map_ids and prog_tags:
 *   __u64 arrays = (1UL << BPF_PROG_INFO_MAP_IDS) |
 *           (1UL << BPF_PROG_INFO_PROG_TAGS);
 *   struct bpf_prog_info_linear *info_linear =
 *           bpf_program__get_prog_info_linear(fd, arrays);
 *
 *   # To save data in file
 *   bpf_program__bpil_addr_to_offs(info_linear);
 *   write(f, info_linear, sizeof(*info_linear) + info_linear->data_len);
 *
 *   # To read data from file
 *   read(f, info_linear, <proper_size>);
 *   bpf_program__bpil_offs_to_addr(info_linear);
 */
enum bpf_prog_info_array {
	BPF_PROG_INFO_FIRST_ARRAY = 0,
	BPF_PROG_INFO_JITED_INSNS = 0,
	BPF_PROG_INFO_XLATED_INSNS,
	BPF_PROG_INFO_MAP_IDS,
	BPF_PROG_INFO_JITED_KSYMS,
	BPF_PROG_INFO_JITED_FUNC_LENS,
	BPF_PROG_INFO_FUNC_INFO,
	BPF_PROG_INFO_LINE_INFO,
	BPF_PROG_INFO_JITED_LINE_INFO,
	BPF_PROG_INFO_PROG_TAGS,
	BPF_PROG_INFO_LAST_ARRAY,
};

struct bpf_prog_info_linear {
	/* size of struct bpf_prog_info, when the tool is compiled */
	__u32			info_len;
	/* total bytes allocated for data, round up to 8 bytes */
	__u32			data_len;
	/* which arrays are included in data */
	__u64			arrays;
	struct bpf_prog_info	info;
	__u8			data[];
};

LIBBPF_DEPRECATED_SINCE(0, 6, "use a custom linear prog_info wrapper")
LIBBPF_API struct bpf_prog_info_linear *
bpf_program__get_prog_info_linear(int fd, __u64 arrays);

LIBBPF_DEPRECATED_SINCE(0, 6, "use a custom linear prog_info wrapper")
LIBBPF_API void
bpf_program__bpil_addr_to_offs(struct bpf_prog_info_linear *info_linear);

LIBBPF_DEPRECATED_SINCE(0, 6, "use a custom linear prog_info wrapper")
LIBBPF_API void
bpf_program__bpil_offs_to_addr(struct bpf_prog_info_linear *info_linear);

/**
 * @brief **libbpf_num_possible_cpus()** is a helper function to get the
 * number of possible CPUs that the host kernel supports and expects.
 * @return number of possible CPUs; or error code on failure
 *
 * Example usage:
 *
 *     int ncpus = libbpf_num_possible_cpus();
 *     if (ncpus < 0) {
 *          // error handling
 *     }
 *     long values[ncpus];
 *     bpf_map_lookup_elem(per_cpu_map_fd, key, values);
 */
LIBBPF_API int libbpf_num_possible_cpus(void);

struct bpf_map_skeleton {
	const char *name;
	struct bpf_map **map;
	void **mmaped;
};

struct bpf_prog_skeleton {
	const char *name;
	struct bpf_program **prog;
	struct bpf_link **link;
};

struct bpf_object_skeleton {
	size_t sz; /* size of this struct, for forward/backward compatibility */

	const char *name;
	const void *data;
	size_t data_sz;

	struct bpf_object **obj;

	int map_cnt;
	int map_skel_sz; /* sizeof(struct bpf_map_skeleton) */
	struct bpf_map_skeleton *maps;

	int prog_cnt;
	int prog_skel_sz; /* sizeof(struct bpf_prog_skeleton) */
	struct bpf_prog_skeleton *progs;
};

LIBBPF_API int
bpf_object__open_skeleton(struct bpf_object_skeleton *s,
			  const struct bpf_object_open_opts *opts);
LIBBPF_API int bpf_object__load_skeleton(struct bpf_object_skeleton *s);
LIBBPF_API int bpf_object__attach_skeleton(struct bpf_object_skeleton *s);
LIBBPF_API void bpf_object__detach_skeleton(struct bpf_object_skeleton *s);
LIBBPF_API void bpf_object__destroy_skeleton(struct bpf_object_skeleton *s);

struct gen_loader_opts {
	size_t sz; /* size of this struct, for forward/backward compatiblity */
	const char *data;
	const char *insns;
	__u32 data_sz;
	__u32 insns_sz;
};

#define gen_loader_opts__last_field insns_sz
LIBBPF_API int bpf_object__gen_loader(struct bpf_object *obj,
				      struct gen_loader_opts *opts);

enum libbpf_tristate {
	TRI_NO = 0,
	TRI_YES = 1,
	TRI_MODULE = 2,
};

struct bpf_linker_opts {
	/* size of this struct, for forward/backward compatiblity */
	size_t sz;
};
#define bpf_linker_opts__last_field sz

struct bpf_linker_file_opts {
	/* size of this struct, for forward/backward compatiblity */
	size_t sz;
};
#define bpf_linker_file_opts__last_field sz

struct bpf_linker;

LIBBPF_API struct bpf_linker *bpf_linker__new(const char *filename, struct bpf_linker_opts *opts);
LIBBPF_API int bpf_linker__add_file(struct bpf_linker *linker,
				    const char *filename,
				    const struct bpf_linker_file_opts *opts);
LIBBPF_API int bpf_linker__finalize(struct bpf_linker *linker);
LIBBPF_API void bpf_linker__free(struct bpf_linker *linker);

#ifdef __cplusplus
} /* extern "C" */
#endif

#endif /* __LIBBPF_LIBBPF_H */