bpf/progs/test_map_in_map.c

0001 // SPDX-License-Identifier: GPL-2.0
0002 /* Copyright (c) 2018 Facebook */
0003 #include <stddef.h>
0004 #include <linux/bpf.h>
0005 #include <linux/types.h>
0006 #include <bpf/bpf_helpers.h>
0007
0008 struct {
0009     __uint(type, BPF_MAP_TYPE_ARRAY_OF_MAPS);
0010     __uint(max_entries, 1);
0011     __uint(map_flags, 0);
0012     __type(key, __u32);
0013     __type(value, __u32);
0014 } mim_array SEC(".maps");
0015
0016 struct {
0017     __uint(type, BPF_MAP_TYPE_HASH_OF_MAPS);
0018     __uint(max_entries, 1);
0019     __uint(map_flags, 0);
0020     __type(key, int);
0021     __type(value, __u32);
0022 } mim_hash SEC(".maps");
0023
0024 SEC("xdp")
0025 int xdp_mimtest0(struct xdp_md *ctx)
0026 {
0027     int value = 123;
0028     int *value_p;
0029     int key = 0;
0030     void *map;
0031
0032     map = bpf_map_lookup_elem(&mim_array, &key);
0033     if (!map)
0034         return XDP_DROP;
0035
0036     bpf_map_update_elem(map, &key, &value, 0);
0037     value_p = bpf_map_lookup_elem(map, &key);
0038     if (!value_p || *value_p != 123)
0039         return XDP_DROP;
0040
0041     map = bpf_map_lookup_elem(&mim_hash, &key);
0042     if (!map)
0043         return XDP_DROP;
0044
0045     bpf_map_update_elem(map, &key, &value, 0);
0046
0047     return XDP_PASS;
0048 }
0049
0050 char _license[] SEC("license") = "GPL";