xref: /OK3568_Linux_fs/kernel/samples/bpf/test_cgrp2_array_pin.c (revision 4882a59341e53eb6f0b4789bf948001014eff981)
1*4882a593Smuzhiyun // SPDX-License-Identifier: GPL-2.0-only
2*4882a593Smuzhiyun /* Copyright (c) 2016 Facebook
3*4882a593Smuzhiyun  */
4*4882a593Smuzhiyun #include <linux/unistd.h>
5*4882a593Smuzhiyun #include <linux/bpf.h>
6*4882a593Smuzhiyun 
7*4882a593Smuzhiyun #include <stdio.h>
8*4882a593Smuzhiyun #include <stdint.h>
9*4882a593Smuzhiyun #include <unistd.h>
10*4882a593Smuzhiyun #include <string.h>
11*4882a593Smuzhiyun #include <errno.h>
12*4882a593Smuzhiyun #include <fcntl.h>
13*4882a593Smuzhiyun 
14*4882a593Smuzhiyun #include <bpf/bpf.h>
15*4882a593Smuzhiyun 
usage(void)16*4882a593Smuzhiyun static void usage(void)
17*4882a593Smuzhiyun {
18*4882a593Smuzhiyun 	printf("Usage: test_cgrp2_array_pin [...]\n");
19*4882a593Smuzhiyun 	printf("       -F <file>   File to pin an BPF cgroup array\n");
20*4882a593Smuzhiyun 	printf("       -U <file>   Update an already pinned BPF cgroup array\n");
21*4882a593Smuzhiyun 	printf("       -v <value>  Full path of the cgroup2\n");
22*4882a593Smuzhiyun 	printf("       -h          Display this help\n");
23*4882a593Smuzhiyun }
24*4882a593Smuzhiyun 
main(int argc,char ** argv)25*4882a593Smuzhiyun int main(int argc, char **argv)
26*4882a593Smuzhiyun {
27*4882a593Smuzhiyun 	const char *pinned_file = NULL, *cg2 = NULL;
28*4882a593Smuzhiyun 	int create_array = 1;
29*4882a593Smuzhiyun 	int array_key = 0;
30*4882a593Smuzhiyun 	int array_fd = -1;
31*4882a593Smuzhiyun 	int cg2_fd = -1;
32*4882a593Smuzhiyun 	int ret = -1;
33*4882a593Smuzhiyun 	int opt;
34*4882a593Smuzhiyun 
35*4882a593Smuzhiyun 	while ((opt = getopt(argc, argv, "F:U:v:")) != -1) {
36*4882a593Smuzhiyun 		switch (opt) {
37*4882a593Smuzhiyun 		/* General args */
38*4882a593Smuzhiyun 		case 'F':
39*4882a593Smuzhiyun 			pinned_file = optarg;
40*4882a593Smuzhiyun 			break;
41*4882a593Smuzhiyun 		case 'U':
42*4882a593Smuzhiyun 			pinned_file = optarg;
43*4882a593Smuzhiyun 			create_array = 0;
44*4882a593Smuzhiyun 			break;
45*4882a593Smuzhiyun 		case 'v':
46*4882a593Smuzhiyun 			cg2 = optarg;
47*4882a593Smuzhiyun 			break;
48*4882a593Smuzhiyun 		default:
49*4882a593Smuzhiyun 			usage();
50*4882a593Smuzhiyun 			goto out;
51*4882a593Smuzhiyun 		}
52*4882a593Smuzhiyun 	}
53*4882a593Smuzhiyun 
54*4882a593Smuzhiyun 	if (!cg2 || !pinned_file) {
55*4882a593Smuzhiyun 		usage();
56*4882a593Smuzhiyun 		goto out;
57*4882a593Smuzhiyun 	}
58*4882a593Smuzhiyun 
59*4882a593Smuzhiyun 	cg2_fd = open(cg2, O_RDONLY);
60*4882a593Smuzhiyun 	if (cg2_fd < 0) {
61*4882a593Smuzhiyun 		fprintf(stderr, "open(%s,...): %s(%d)\n",
62*4882a593Smuzhiyun 			cg2, strerror(errno), errno);
63*4882a593Smuzhiyun 		goto out;
64*4882a593Smuzhiyun 	}
65*4882a593Smuzhiyun 
66*4882a593Smuzhiyun 	if (create_array) {
67*4882a593Smuzhiyun 		array_fd = bpf_create_map(BPF_MAP_TYPE_CGROUP_ARRAY,
68*4882a593Smuzhiyun 					  sizeof(uint32_t), sizeof(uint32_t),
69*4882a593Smuzhiyun 					  1, 0);
70*4882a593Smuzhiyun 		if (array_fd < 0) {
71*4882a593Smuzhiyun 			fprintf(stderr,
72*4882a593Smuzhiyun 				"bpf_create_map(BPF_MAP_TYPE_CGROUP_ARRAY,...): %s(%d)\n",
73*4882a593Smuzhiyun 				strerror(errno), errno);
74*4882a593Smuzhiyun 			goto out;
75*4882a593Smuzhiyun 		}
76*4882a593Smuzhiyun 	} else {
77*4882a593Smuzhiyun 		array_fd = bpf_obj_get(pinned_file);
78*4882a593Smuzhiyun 		if (array_fd < 0) {
79*4882a593Smuzhiyun 			fprintf(stderr, "bpf_obj_get(%s): %s(%d)\n",
80*4882a593Smuzhiyun 				pinned_file, strerror(errno), errno);
81*4882a593Smuzhiyun 			goto out;
82*4882a593Smuzhiyun 		}
83*4882a593Smuzhiyun 	}
84*4882a593Smuzhiyun 
85*4882a593Smuzhiyun 	ret = bpf_map_update_elem(array_fd, &array_key, &cg2_fd, 0);
86*4882a593Smuzhiyun 	if (ret) {
87*4882a593Smuzhiyun 		perror("bpf_map_update_elem");
88*4882a593Smuzhiyun 		goto out;
89*4882a593Smuzhiyun 	}
90*4882a593Smuzhiyun 
91*4882a593Smuzhiyun 	if (create_array) {
92*4882a593Smuzhiyun 		ret = bpf_obj_pin(array_fd, pinned_file);
93*4882a593Smuzhiyun 		if (ret) {
94*4882a593Smuzhiyun 			fprintf(stderr, "bpf_obj_pin(..., %s): %s(%d)\n",
95*4882a593Smuzhiyun 				pinned_file, strerror(errno), errno);
96*4882a593Smuzhiyun 			goto out;
97*4882a593Smuzhiyun 		}
98*4882a593Smuzhiyun 	}
99*4882a593Smuzhiyun 
100*4882a593Smuzhiyun out:
101*4882a593Smuzhiyun 	if (array_fd != -1)
102*4882a593Smuzhiyun 		close(array_fd);
103*4882a593Smuzhiyun 	if (cg2_fd != -1)
104*4882a593Smuzhiyun 		close(cg2_fd);
105*4882a593Smuzhiyun 	return ret;
106*4882a593Smuzhiyun }
107