diff options
Diffstat (limited to 'tools/testing/selftests/bpf/progs/test_btf_map_in_map.c')
-rw-r--r-- | tools/testing/selftests/bpf/progs/test_btf_map_in_map.c | 76 |
1 files changed, 76 insertions, 0 deletions
diff --git a/tools/testing/selftests/bpf/progs/test_btf_map_in_map.c b/tools/testing/selftests/bpf/progs/test_btf_map_in_map.c new file mode 100644 index 000000000000..e5093796be97 --- /dev/null +++ b/tools/testing/selftests/bpf/progs/test_btf_map_in_map.c @@ -0,0 +1,76 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +/* Copyright (c) 2020 Facebook */ +#include <linux/bpf.h> +#include <bpf/bpf_helpers.h> + +struct inner_map { + __uint(type, BPF_MAP_TYPE_ARRAY); + __uint(max_entries, 1); + __type(key, int); + __type(value, int); +} inner_map1 SEC(".maps"), + inner_map2 SEC(".maps"); + +struct outer_arr { + __uint(type, BPF_MAP_TYPE_ARRAY_OF_MAPS); + __uint(max_entries, 3); + __uint(key_size, sizeof(int)); + __uint(value_size, sizeof(int)); + /* it's possible to use anonymous struct as inner map definition here */ + __array(values, struct { + __uint(type, BPF_MAP_TYPE_ARRAY); + /* changing max_entries to 2 will fail during load + * due to incompatibility with inner_map definition */ + __uint(max_entries, 1); + __type(key, int); + __type(value, int); + }); +} outer_arr SEC(".maps") = { + /* (void *) cast is necessary because we didn't use `struct inner_map` + * in __inner(values, ...) + * Actually, a conscious effort is required to screw up initialization + * of inner map slots, which is a great thing! + */ + .values = { (void *)&inner_map1, 0, (void *)&inner_map2 }, +}; + +struct outer_hash { + __uint(type, BPF_MAP_TYPE_HASH_OF_MAPS); + __uint(max_entries, 5); + __uint(key_size, sizeof(int)); + /* Here everything works flawlessly due to reuse of struct inner_map + * and compiler will complain at the attempt to use non-inner_map + * references below. This is great experience. + */ + __array(values, struct inner_map); +} outer_hash SEC(".maps") = { + .values = { + [0] = &inner_map2, + [4] = &inner_map1, + }, +}; + +int input = 0; + +SEC("raw_tp/sys_enter") +int handle__sys_enter(void *ctx) +{ + struct inner_map *inner_map; + int key = 0, val; + + inner_map = bpf_map_lookup_elem(&outer_arr, &key); + if (!inner_map) + return 1; + val = input; + bpf_map_update_elem(inner_map, &key, &val, 0); + + inner_map = bpf_map_lookup_elem(&outer_hash, &key); + if (!inner_map) + return 1; + val = input + 1; + bpf_map_update_elem(inner_map, &key, &val, 0); + + return 0; +} + +char _license[] SEC("license") = "GPL"; |