Commit a4b2f3cf authored by Stanislav Fomichev's avatar Stanislav Fomichev Committed by Alexei Starovoitov
Browse files

libbpf: implement bpf_prog_query_opts 



Implement bpf_prog_query_opts as a more expendable version of
bpf_prog_query. Expose new prog_attach_flags and attach_btf_func_id as
well:

* prog_attach_flags is a per-program attach_type; relevant only for
  lsm cgroup program which might have different attach_flags
  per attach_btf_id
* attach_btf_func_id is a new field expose for prog_query which
  specifies real btf function id for lsm cgroup attachments

Acked-by: default avatarMartin KaFai Lau <kafai@fb.com>
Acked-by: default avatarAndrii Nakryiko <andrii@kernel.org>
Signed-off-by: default avatarStanislav Fomichev <sdf@google.com>
Link: https://lore.kernel.org/r/20220628174314.1216643-10-sdf@google.com


Signed-off-by: default avatarAlexei Starovoitov <ast@kernel.org>
parent bffcf348

tools/lib/bpf/bpf.c

+31 −7
Original line number Diff line number Diff line
@@ -795,24 +795,48 @@ int bpf_iter_create(int link_fd) 
	return libbpf_err_errno(fd);

}



int bpf_prog_query(int target_fd, enum bpf_attach_type type, __u32 query_flags,

		   __u32 *attach_flags, __u32 *prog_ids, __u32 *prog_cnt)

int bpf_prog_query_opts(int target_fd,

			enum bpf_attach_type type,

			struct bpf_prog_query_opts *opts)

{

	union bpf_attr attr;

	int ret;



	if (!OPTS_VALID(opts, bpf_prog_query_opts))

		return libbpf_err(-EINVAL);



	memset(&attr, 0, sizeof(attr));



	attr.query.target_fd	= target_fd;

	attr.query.attach_type	= type;

	attr.query.query_flags	= query_flags;

	attr.query.prog_cnt	= *prog_cnt;

	attr.query.prog_ids	= ptr_to_u64(prog_ids);

	attr.query.query_flags	= OPTS_GET(opts, query_flags, 0);

	attr.query.prog_cnt	= OPTS_GET(opts, prog_cnt, 0);

	attr.query.prog_ids	= ptr_to_u64(OPTS_GET(opts, prog_ids, NULL));

	attr.query.prog_attach_flags = ptr_to_u64(OPTS_GET(opts, prog_attach_flags, NULL));



	ret = sys_bpf(BPF_PROG_QUERY, &attr, sizeof(attr));



	OPTS_SET(opts, attach_flags, attr.query.attach_flags);

	OPTS_SET(opts, prog_cnt, attr.query.prog_cnt);



	return libbpf_err_errno(ret);

}



int bpf_prog_query(int target_fd, enum bpf_attach_type type, __u32 query_flags,

		   __u32 *attach_flags, __u32 *prog_ids, __u32 *prog_cnt)

{

	LIBBPF_OPTS(bpf_prog_query_opts, opts);

	int ret;



	opts.query_flags = query_flags;

	opts.prog_ids = prog_ids;

	opts.prog_cnt = *prog_cnt;



	ret = bpf_prog_query_opts(target_fd, type, &opts);



	if (attach_flags)

		*attach_flags = attr.query.attach_flags;

	*prog_cnt = attr.query.prog_cnt;

		*attach_flags = opts.attach_flags;

	*prog_cnt = opts.prog_cnt;



	return libbpf_err_errno(ret);

}

tools/lib/bpf/bpf.h

+15 −0
Original line number Diff line number Diff line
@@ -359,9 +359,24 @@ LIBBPF_API int bpf_map_get_fd_by_id(__u32 id); 
LIBBPF_API int bpf_btf_get_fd_by_id(__u32 id);

LIBBPF_API int bpf_link_get_fd_by_id(__u32 id);

LIBBPF_API int bpf_obj_get_info_by_fd(int bpf_fd, void *info, __u32 *info_len);



struct bpf_prog_query_opts {

	size_t sz; /* size of this struct for forward/backward compatibility */

	__u32 query_flags;

	__u32 attach_flags; /* output argument */

	__u32 *prog_ids;

	__u32 prog_cnt; /* input+output argument */

	__u32 *prog_attach_flags;

};

#define bpf_prog_query_opts__last_field prog_attach_flags



LIBBPF_API int bpf_prog_query_opts(int target_fd,

				   enum bpf_attach_type type,

				   struct bpf_prog_query_opts *opts);

LIBBPF_API int bpf_prog_query(int target_fd, enum bpf_attach_type type,

			      __u32 query_flags, __u32 *attach_flags,

			      __u32 *prog_ids, __u32 *prog_cnt);



LIBBPF_API int bpf_raw_tracepoint_open(const char *name, int prog_fd);

LIBBPF_API int bpf_task_fd_query(int pid, int fd, __u32 flags, char *buf,

				 __u32 *buf_len, __u32 *prog_id, __u32 *fd_type,

tools/lib/bpf/libbpf.map

+1 −0
Original line number Diff line number Diff line
@@ -355,6 +355,7 @@ LIBBPF_0.8.0 { 


LIBBPF_1.0.0 {

	global:

		bpf_prog_query_opts;

		btf__add_enum64;

		btf__add_enum64_value;

		libbpf_bpf_attach_type_str;