1// SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
  2// Copyright (C) 2020 Facebook
  3
  4#ifndef _GNU_SOURCE
  5#define _GNU_SOURCE
  6#endif
  7#include <errno.h>
  8#include <unistd.h>
  9#include <linux/err.h>
 10#include <bpf/libbpf.h>
 11
 12#include "main.h"
 13
 14static int do_pin(int argc, char **argv)
 15{
 16	DECLARE_LIBBPF_OPTS(bpf_iter_attach_opts, iter_opts);
 17	union bpf_iter_link_info linfo;
 18	const char *objfile, *path;
 19	struct bpf_program *prog;
 20	struct bpf_object *obj;
 21	struct bpf_link *link;
 22	int err = -1, map_fd = -1;
 23
 24	if (!REQ_ARGS(2))
 25		usage();
 26
 27	objfile = GET_ARG();
 28	path = GET_ARG();
 29
 30	/* optional arguments */
 31	if (argc) {
 32		if (is_prefix(*argv, "map")) {
 33			NEXT_ARG();
 34
 35			if (!REQ_ARGS(2)) {
 36				p_err("incorrect map spec");
 37				return -1;
 38			}
 39
 40			map_fd = map_parse_fd(&argc, &argv);
 41			if (map_fd < 0)
 42				return -1;
 43
 44			memset(&linfo, 0, sizeof(linfo));
 45			linfo.map.map_fd = map_fd;
 46			iter_opts.link_info = &linfo;
 47			iter_opts.link_info_len = sizeof(linfo);
 48		}
 49	}
 50
 51	obj = bpf_object__open(objfile);
 52	if (!obj) {
 53		err = -errno;
 54		p_err("can't open objfile %s", objfile);
 55		goto close_map_fd;
 56	}
 57
 58	err = bpf_object__load(obj);
 59	if (err) {
 60		p_err("can't load objfile %s", objfile);
 61		goto close_obj;
 62	}
 63
 64	prog = bpf_object__next_program(obj, NULL);
 65	if (!prog) {
 66		err = -errno;
 67		p_err("can't find bpf program in objfile %s", objfile);
 68		goto close_obj;
 69	}
 70
 71	link = bpf_program__attach_iter(prog, &iter_opts);
 72	if (!link) {
 73		err = -errno;
 74		p_err("attach_iter failed for program %s",
 75		      bpf_program__name(prog));
 76		goto close_obj;
 77	}
 78
 79	err = mount_bpffs_for_pin(path, false);
 80	if (err)
 81		goto close_link;
 82
 83	err = bpf_link__pin(link, path);
 84	if (err) {
 85		p_err("pin_iter failed for program %s to path %s",
 86		      bpf_program__name(prog), path);
 87		goto close_link;
 88	}
 89
 90close_link:
 91	bpf_link__destroy(link);
 92close_obj:
 93	bpf_object__close(obj);
 94close_map_fd:
 95	if (map_fd >= 0)
 96		close(map_fd);
 97	return err;
 98}
 99
100static int do_help(int argc, char **argv)
101{
102	fprintf(stderr,
103		"Usage: %1$s %2$s pin OBJ PATH [map MAP]\n"
104		"       %1$s %2$s help\n"
105		"\n"
106		"       " HELP_SPEC_MAP "\n"
107		"       " HELP_SPEC_OPTIONS " }\n"
108		"",
109		bin_name, "iter");
110
111	return 0;
112}
113
114static const struct cmd cmds[] = {
115	{ "help",	do_help },
116	{ "pin",	do_pin },
117	{ 0 }
118};
119
120int do_iter(int argc, char **argv)
121{
122	return cmd_select(cmds, argc, argv, do_help);
123}