1 /* SPDX-License-Identifier: (LGPL-2.1 OR BSD-2-Clause) */
2 /* Copyright (c) 2018 Facebook */
7 #include <linux/types.h>
14 #define LIBBPF_API __attribute__((visibility("default")))
17 #define BTF_ELF_SEC ".BTF"
18 #define BTF_EXT_ELF_SEC ".BTF.ext"
25 * The .BTF.ext ELF section layout defined as
26 * struct btf_ext_header
27 * func_info subsection
29 * The func_info subsection layout:
30 * record size for struct bpf_func_info in the func_info subsection
31 * struct btf_sec_func_info for section #1
32 * a list of bpf_func_info records for section #1
33 * where struct bpf_func_info mimics one in include/uapi/linux/bpf.h
34 * but may not be identical
35 * struct btf_sec_func_info for section #2
36 * a list of bpf_func_info records for section #2
39 * Note that the bpf_func_info record size in .BTF.ext may not
40 * be the same as the one defined in include/uapi/linux/bpf.h.
41 * The loader should ensure that record_size meets minimum
42 * requirement and pass the record as is to the kernel. The
43 * kernel will handle the func_info properly based on its contents.
45 struct btf_ext_header {
51 /* All offsets are in bytes relative to the end of this header */
56 struct btf_sec_func_info {
59 /* Followed by num_func_info number of bpf func_info records */
63 typedef int (*btf_print_fn_t)(const char *, ...)
64 __attribute__((format(printf, 1, 2)));
66 LIBBPF_API void btf__free(struct btf *btf);
67 LIBBPF_API struct btf *btf__new(__u8 *data, __u32 size, btf_print_fn_t err_log);
68 LIBBPF_API __s32 btf__find_by_name(const struct btf *btf,
69 const char *type_name);
70 LIBBPF_API const struct btf_type *btf__type_by_id(const struct btf *btf,
72 LIBBPF_API __s64 btf__resolve_size(const struct btf *btf, __u32 type_id);
73 LIBBPF_API int btf__resolve_type(const struct btf *btf, __u32 type_id);
74 LIBBPF_API int btf__fd(const struct btf *btf);
75 LIBBPF_API const char *btf__name_by_offset(const struct btf *btf, __u32 offset);
76 LIBBPF_API int btf__get_from_id(__u32 id, struct btf **btf);
78 struct btf_ext *btf_ext__new(__u8 *data, __u32 size, btf_print_fn_t err_log);
79 void btf_ext__free(struct btf_ext *btf_ext);
80 int btf_ext__reloc_init(struct btf *btf, struct btf_ext *btf_ext,
81 const char *sec_name, void **func_info,
82 __u32 *func_info_rec_size, __u32 *func_info_len);
83 int btf_ext__reloc(struct btf *btf, struct btf_ext *btf_ext,
84 const char *sec_name, __u32 insns_cnt, void **func_info,
85 __u32 *func_info_len);
91 #endif /* __LIBBPF_BTF_H */