bpf: Switch btf_parse_vmlinux to btf_find_by_name_kind (a2d0d62f) · Commits · 戴 / test

btf_parse_vmlinux() implements manual search for struct bpf_ctx_convert since at the time of implementing btf_find_by_name_kind() was not available. Later btf_find_by_name_kind() was introduced in ("bpf: Introduce BPF_PROG_TYPE_STRUCT_OPS"). It provides similar search functionality and can be leveraged in btf_parse_vmlinux(). Do it. Signed-off-by:

Andrey Ignatov <rdna@fb.com> Signed-off-by:

Daniel Borkmann <daniel@iogearbox.net> Acked-by:

Andrii Nakryiko <andriin@fb.com> Acked-by:

John Fastabend <john.fastabend@gmail.com> Acked-by:

Martin KaFai Lau <kafai@fb.com> Link: https://lore.kernel.org/bpf/6e12d5c3e8a3d552925913ef73a695dd1bb27800.1592600985.git.rdna@fb.com

kernel/bpf/btf.c

+6 −17

Original line number	Diff line number	Diff line
		@@ -3591,7 +3591,7 @@ struct btf *btf_parse_vmlinux(void)
		struct btf_verifier_env *env = NULL;
		struct bpf_verifier_log *log;
		struct btf *btf = NULL;
		int err, i;
		int err, btf_id;

		env = kzalloc(sizeof(*env), GFP_KERNEL \| __GFP_NOWARN);
		if (!env)
		@@ -3625,24 +3625,13 @@ struct btf *btf_parse_vmlinux(void)
		goto errout;

		/* find struct bpf_ctx_convert for type checking later */
		for (i = 1; i <= btf->nr_types; i++) {
		const struct btf_type *t;
		const char *tname;

		t = btf_type_by_id(btf, i);
		if (!__btf_type_is_struct(t))
		continue;
		tname = __btf_name_by_offset(btf, t->name_off);
		if (!strcmp(tname, "bpf_ctx_convert")) {
		/* btf_parse_vmlinux() runs under bpf_verifier_lock */
		bpf_ctx_convert.t = t;
		break;
		}
		}
		if (i > btf->nr_types) {
		err = -ENOENT;
		btf_id = btf_find_by_name_kind(btf, "bpf_ctx_convert", BTF_KIND_STRUCT);
		if (btf_id < 0) {
		err = btf_id;
		goto errout;
		}
		/* btf_parse_vmlinux() runs under bpf_verifier_lock */
		bpf_ctx_convert.t = btf_type_by_id(btf, btf_id);

		bpf_struct_ops_init(btf, log);

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