diff --git a/tools/lib/bpf/libbpf.c b/tools/lib/bpf/libbpf.c index d69f81052c2f6f0b16df85d51da777d6ec4de363..64e7dc7c51981c1443d3ec6c9f72176a2346679b 100644 --- a/tools/lib/bpf/libbpf.c +++ b/tools/lib/bpf/libbpf.c @@ -6588,8 +6588,6 @@ int bpf_program__load(struct bpf_program *prog, char *license, __u32 kern_ver) out: if (err) pr_warn("failed to load program '%s'\n", prog->name); - zfree(&prog->insns); - prog->insns_cnt = 0; return libbpf_err(err); } @@ -8060,6 +8058,16 @@ size_t bpf_program__size(const struct bpf_program *prog) return prog->insns_cnt * BPF_INSN_SZ; } +const struct bpf_insn *bpf_program__insns(const struct bpf_program *prog) +{ + return prog->insns; +} + +size_t bpf_program__insn_cnt(const struct bpf_program *prog) +{ + return prog->insns_cnt; +} + int bpf_program__set_prep(struct bpf_program *prog, int nr_instances, bpf_program_prep_t prep) { diff --git a/tools/lib/bpf/libbpf.h b/tools/lib/bpf/libbpf.h index d9815eee26ac8291f6bb1a59e504a14fbcb4941e..0940ffbef461f25c599233d36c6128fd80c634a3 100644 --- a/tools/lib/bpf/libbpf.h +++ b/tools/lib/bpf/libbpf.h @@ -219,6 +219,40 @@ LIBBPF_API int bpf_program__set_autoload(struct bpf_program *prog, bool autoload /* returns program size in bytes */ 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_API int bpf_program__load(struct bpf_program *prog, char *license, __u32 kern_version); LIBBPF_API int bpf_program__fd(const struct bpf_program *prog); @@ -294,8 +328,6 @@ LIBBPF_API struct bpf_link * bpf_program__attach_iter(const struct bpf_program *prog, const struct bpf_iter_attach_opts *opts); -struct bpf_insn; - /* * Libbpf allows callers to adjust BPF programs before being loaded * into kernel. One program in an object file can be transformed into diff --git a/tools/lib/bpf/libbpf.map b/tools/lib/bpf/libbpf.map index 6b9da58d46d891935e3733032102174be744e00a..29585c8155457977581fd3662f6a5648b39c4741 100644 --- a/tools/lib/bpf/libbpf.map +++ b/tools/lib/bpf/libbpf.map @@ -384,6 +384,8 @@ LIBBPF_0.5.0 { LIBBPF_0.6.0 { global: + bpf_program__insn_cnt; + bpf_program__insns; btf__add_btf; btf__add_decl_tag; } LIBBPF_0.5.0;