libbpf: Add btf__parse_raw() and generic btf__parse() APIs (94a1fedd) · Commits · 戴 / test

tools/lib/bpf/btf.c

+78 −36

Original line number	Diff line number	Diff line
		@@ -562,6 +562,83 @@ done:
		return btf;
		}

		struct btf btf__parse_raw(const char path)
		{
		void *data = NULL;
		struct btf *btf;
		FILE *f = NULL;
		__u16 magic;
		int err = 0;
		long sz;

		f = fopen(path, "rb");
		if (!f) {
		err = -errno;
		goto err_out;
		}

		/* check BTF magic */
		if (fread(&magic, 1, sizeof(magic), f) < sizeof(magic)) {
		err = -EIO;
		goto err_out;
		}
		if (magic != BTF_MAGIC) {
		/* definitely not a raw BTF */
		err = -EPROTO;
		goto err_out;
		}

		/* get file size */
		if (fseek(f, 0, SEEK_END)) {
		err = -errno;
		goto err_out;
		}
		sz = ftell(f);
		if (sz < 0) {
		err = -errno;
		goto err_out;
		}
		/* rewind to the start */
		if (fseek(f, 0, SEEK_SET)) {
		err = -errno;
		goto err_out;
		}

		/* pre-alloc memory and read all of BTF data */
		data = malloc(sz);
		if (!data) {
		err = -ENOMEM;
		goto err_out;
		}
		if (fread(data, 1, sz, f) < sz) {
		err = -EIO;
		goto err_out;
		}

		/* finally parse BTF data */
		btf = btf__new(data, sz);

		err_out:
		free(data);
		if (f)
		fclose(f);
		return err ? ERR_PTR(err) : btf;
		}

		struct btf btf__parse(const char path, struct btf_ext **btf_ext)
		{
		struct btf *btf;

		if (btf_ext)
		*btf_ext = NULL;

		btf = btf__parse_raw(path);
		if (!IS_ERR(btf) \|\| PTR_ERR(btf) != -EPROTO)
		return btf;

		return btf__parse_elf(path, btf_ext);
		}

		static int compare_vsi_off(const void _a, const void _b)
		{
		const struct btf_var_secinfo *a = _a;
		@@ -2951,41 +3028,6 @@ static int btf_dedup_remap_types(struct btf_dedup *d)
		return 0;
		}

		static struct btf btf_load_raw(const char path)
		{
		struct btf *btf;
		size_t read_cnt;
		struct stat st;
		void *data;
		FILE *f;

		if (stat(path, &st))
		return ERR_PTR(-errno);

		data = malloc(st.st_size);
		if (!data)
		return ERR_PTR(-ENOMEM);

		f = fopen(path, "rb");
		if (!f) {
		btf = ERR_PTR(-errno);
		goto cleanup;
		}

		read_cnt = fread(data, 1, st.st_size, f);
		fclose(f);
		if (read_cnt < st.st_size) {
		btf = ERR_PTR(-EBADF);
		goto cleanup;
		}

		btf = btf__new(data, read_cnt);

		cleanup:
		free(data);
		return btf;
		}

		/*
		* Probe few well-known locations for vmlinux kernel image and try to load BTF
		* data out of it to use for target BTF.
		@@ -3021,7 +3063,7 @@ struct btf *libbpf_find_kernel_btf(void)
		continue;

		if (locations[i].raw_btf)
		btf = btf_load_raw(path);
		btf = btf__parse_raw(path);
		else
		btf = btf__parse_elf(path, NULL);

tools/lib/bpf/btf.h

+3 −2

Original line number	Diff line number	Diff line
		@@ -64,8 +64,9 @@ struct btf_ext_header {

		LIBBPF_API void btf__free(struct btf *btf);
		LIBBPF_API struct btf btf__new(const void data, __u32 size);
		LIBBPF_API struct btf btf__parse_elf(const char path,
		struct btf_ext **btf_ext);
		LIBBPF_API struct btf btf__parse(const char path, struct btf_ext **btf_ext);
		LIBBPF_API struct btf btf__parse_elf(const char path, struct btf_ext **btf_ext);
		LIBBPF_API struct btf btf__parse_raw(const char path);
		LIBBPF_API int btf__finalize_data(struct bpf_object obj, struct btf btf);
		LIBBPF_API int btf__load(struct btf *btf);
		LIBBPF_API __s32 btf__find_by_name(const struct btf *btf,

tools/lib/bpf/libbpf.map

+2 −0

Original line number	Diff line number	Diff line
		@@ -293,5 +293,7 @@ LIBBPF_0.1.0 {
		bpf_program__is_sk_lookup;
		bpf_program__set_autoload;
		bpf_program__set_sk_lookup;
		btf__parse;
		btf__parse_raw;
		btf__set_fd;
		} LIBBPF_0.0.9;

Admin message