xref: /kernel/linux/linux-5.10/tools/bpf/bpftool/iter.c (revision 8c2ecf20)
1// SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
2// Copyright (C) 2020 Facebook
3
4#define _GNU_SOURCE
5#include <unistd.h>
6#include <linux/err.h>
7#include <bpf/libbpf.h>
8
9#include "main.h"
10
11static int do_pin(int argc, char **argv)
12{
13	DECLARE_LIBBPF_OPTS(bpf_iter_attach_opts, iter_opts);
14	union bpf_iter_link_info linfo;
15	const char *objfile, *path;
16	struct bpf_program *prog;
17	struct bpf_object *obj;
18	struct bpf_link *link;
19	int err = -1, map_fd = -1;
20
21	if (!REQ_ARGS(2))
22		usage();
23
24	objfile = GET_ARG();
25	path = GET_ARG();
26
27	/* optional arguments */
28	if (argc) {
29		if (is_prefix(*argv, "map")) {
30			NEXT_ARG();
31
32			if (!REQ_ARGS(2)) {
33				p_err("incorrect map spec");
34				return -1;
35			}
36
37			map_fd = map_parse_fd(&argc, &argv);
38			if (map_fd < 0)
39				return -1;
40
41			memset(&linfo, 0, sizeof(linfo));
42			linfo.map.map_fd = map_fd;
43			iter_opts.link_info = &linfo;
44			iter_opts.link_info_len = sizeof(linfo);
45		}
46	}
47
48	obj = bpf_object__open(objfile);
49	if (IS_ERR(obj)) {
50		p_err("can't open objfile %s", objfile);
51		goto close_map_fd;
52	}
53
54	err = bpf_object__load(obj);
55	if (err) {
56		p_err("can't load objfile %s", objfile);
57		goto close_obj;
58	}
59
60	prog = bpf_program__next(NULL, obj);
61	if (!prog) {
62		p_err("can't find bpf program in objfile %s", objfile);
63		goto close_obj;
64	}
65
66	link = bpf_program__attach_iter(prog, &iter_opts);
67	if (IS_ERR(link)) {
68		err = PTR_ERR(link);
69		p_err("attach_iter failed for program %s",
70		      bpf_program__name(prog));
71		goto close_obj;
72	}
73
74	err = mount_bpffs_for_pin(path);
75	if (err)
76		goto close_link;
77
78	err = bpf_link__pin(link, path);
79	if (err) {
80		p_err("pin_iter failed for program %s to path %s",
81		      bpf_program__name(prog), path);
82		goto close_link;
83	}
84
85close_link:
86	bpf_link__destroy(link);
87close_obj:
88	bpf_object__close(obj);
89close_map_fd:
90	if (map_fd >= 0)
91		close(map_fd);
92	return err;
93}
94
95static int do_help(int argc, char **argv)
96{
97	fprintf(stderr,
98		"Usage: %1$s %2$s pin OBJ PATH [map MAP]\n"
99		"       %1$s %2$s help\n"
100		"       " HELP_SPEC_MAP "\n"
101		"",
102		bin_name, "iter");
103
104	return 0;
105}
106
107static const struct cmd cmds[] = {
108	{ "help",	do_help },
109	{ "pin",	do_pin },
110	{ 0 }
111};
112
113int do_iter(int argc, char **argv)
114{
115	return cmd_select(cmds, argc, argv, do_help);
116}
117