1/*
2 * Common eBPF ELF object loading operations.
3 *
4 * Copyright (C) 2013-2015 Alexei Starovoitov <ast@kernel.org>
5 * Copyright (C) 2015 Wang Nan <wangnan0@huawei.com>
6 * Copyright (C) 2015 Huawei Inc.
7 */
8#ifndef __BPF_LIBBPF_H
9#define __BPF_LIBBPF_H
10
11#include <stdio.h>
12#include <stdbool.h>
13#include <linux/err.h>
14
15enum libbpf_errno {
16	__LIBBPF_ERRNO__START = 4000,
17
18	/* Something wrong in libelf */
19	LIBBPF_ERRNO__LIBELF = __LIBBPF_ERRNO__START,
20	LIBBPF_ERRNO__FORMAT,	/* BPF object format invalid */
21	LIBBPF_ERRNO__KVERSION,	/* Incorrect or no 'version' section */
22	LIBBPF_ERRNO__ENDIAN,	/* Endian missmatch */
23	LIBBPF_ERRNO__INTERNAL,	/* Internal error in libbpf */
24	LIBBPF_ERRNO__RELOC,	/* Relocation failed */
25	LIBBPF_ERRNO__LOAD,	/* Load program failure for unknown reason */
26	LIBBPF_ERRNO__VERIFY,	/* Kernel verifier blocks program loading */
27	LIBBPF_ERRNO__PROG2BIG,	/* Program too big */
28	LIBBPF_ERRNO__KVER,	/* Incorrect kernel version */
29	__LIBBPF_ERRNO__END,
30};
31
32int libbpf_strerror(int err, char *buf, size_t size);
33
34/*
35 * In include/linux/compiler-gcc.h, __printf is defined. However
36 * it should be better if libbpf.h doesn't depend on Linux header file.
37 * So instead of __printf, here we use gcc attribute directly.
38 */
39typedef int (*libbpf_print_fn_t)(const char *, ...)
40	__attribute__((format(printf, 1, 2)));
41
42void libbpf_set_print(libbpf_print_fn_t warn,
43		      libbpf_print_fn_t info,
44		      libbpf_print_fn_t debug);
45
46/* Hide internal to user */
47struct bpf_object;
48
49struct bpf_object *bpf_object__open(const char *path);
50struct bpf_object *bpf_object__open_buffer(void *obj_buf,
51					   size_t obj_buf_sz,
52					   const char *name);
53void bpf_object__close(struct bpf_object *object);
54
55/* Load/unload object into/from kernel */
56int bpf_object__load(struct bpf_object *obj);
57int bpf_object__unload(struct bpf_object *obj);
58const char *bpf_object__get_name(struct bpf_object *obj);
59unsigned int bpf_object__get_kversion(struct bpf_object *obj);
60
61struct bpf_object *bpf_object__next(struct bpf_object *prev);
62#define bpf_object__for_each_safe(pos, tmp)			\
63	for ((pos) = bpf_object__next(NULL),		\
64		(tmp) = bpf_object__next(pos);		\
65	     (pos) != NULL;				\
66	     (pos) = (tmp), (tmp) = bpf_object__next(tmp))
67
68/* Accessors of bpf_program. */
69struct bpf_program;
70struct bpf_program *bpf_program__next(struct bpf_program *prog,
71				      struct bpf_object *obj);
72
73#define bpf_object__for_each_program(pos, obj)		\
74	for ((pos) = bpf_program__next(NULL, (obj));	\
75	     (pos) != NULL;				\
76	     (pos) = bpf_program__next((pos), (obj)))
77
78typedef void (*bpf_program_clear_priv_t)(struct bpf_program *,
79					 void *);
80
81int bpf_program__set_private(struct bpf_program *prog, void *priv,
82			     bpf_program_clear_priv_t clear_priv);
83
84int bpf_program__get_private(struct bpf_program *prog,
85			     void **ppriv);
86
87const char *bpf_program__title(struct bpf_program *prog, bool needs_copy);
88
89int bpf_program__fd(struct bpf_program *prog);
90
91/*
92 * We don't need __attribute__((packed)) now since it is
93 * unnecessary for 'bpf_map_def' because they are all aligned.
94 * In addition, using it will trigger -Wpacked warning message,
95 * and will be treated as an error due to -Werror.
96 */
97struct bpf_map_def {
98	unsigned int type;
99	unsigned int key_size;
100	unsigned int value_size;
101	unsigned int max_entries;
102};
103
104#endif
105