From 81372e121802fd57892a0b44d93cc747d9568627 Mon Sep 17 00:00:00 2001 From: Andrii Nakryiko Date: Tue, 7 Jul 2020 18:53:14 -0700 Subject: libbpf: Add btf__set_fd() for more control over loaded BTF FD Add setter for BTF FD to allow application more fine-grained control in more advanced scenarios. Storing BTF FD inside `struct btf` provides little benefit and probably would be better done differently (e.g., btf__load() could just return FD on success), but we are stuck with this due to backwards compatibility. The main problem is that it's impossible to load BTF and than free user-space memory, but keep FD intact, because `struct btf` assumes ownership of that FD upon successful load and will attempt to close it during btf__free(). To allow callers (e.g., libbpf itself for BTF sanitization) to have more control over this, add btf__set_fd() to allow to reset FD arbitrarily, if necessary. Signed-off-by: Andrii Nakryiko Signed-off-by: Daniel Borkmann Link: https://lore.kernel.org/bpf/20200708015318.3827358-3-andriin@fb.com --- tools/lib/bpf/btf.h | 1 + 1 file changed, 1 insertion(+) (limited to 'tools/lib/bpf/btf.h') diff --git a/tools/lib/bpf/btf.h b/tools/lib/bpf/btf.h index 06cd1731c154..173eff23c472 100644 --- a/tools/lib/bpf/btf.h +++ b/tools/lib/bpf/btf.h @@ -79,6 +79,7 @@ LIBBPF_API __s64 btf__resolve_size(const struct btf *btf, __u32 type_id); LIBBPF_API int btf__resolve_type(const struct btf *btf, __u32 type_id); LIBBPF_API int btf__align_of(const struct btf *btf, __u32 id); LIBBPF_API int btf__fd(const struct btf *btf); +LIBBPF_API void btf__set_fd(struct btf *btf, int fd); LIBBPF_API const void *btf__get_raw_data(const struct btf *btf, __u32 *size); LIBBPF_API const char *btf__name_by_offset(const struct btf *btf, __u32 offset); LIBBPF_API int btf__get_from_id(__u32 id, struct btf **btf); -- cgit