bpf: adding tests for map_in_map helpber in libbpf

adding test/example of bpf_map__set_inner_map_fd usage

Signed-off-by: Nikita V. Shirokov <tehnerd@tehnerd.com>
Acked-by: Yonghong Song <yhs@fb.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>

diff --git a/tools/testing/selftests/bpf/Makefile b/tools/testing/selftests/bpf/Makefile
index 1dde03ea1484802878306ec1ae4ec93edc3e41e4..43157bd891655a2d6cc6a25b4421ea7728edd334 100644 (file)
--- a/tools/testing/selftests/bpf/Makefile
+++ b/tools/testing/selftests/bpf/Makefile
@@ -38,7 +38,8 @@ TEST_GEN_FILES = test_pkt_access.o test_xdp.o test_l4lb.o test_tcp_estats.o test
        test_lwt_seg6local.o sendmsg4_prog.o sendmsg6_prog.o test_lirc_mode2_kern.o \
        get_cgroup_id_kern.o socket_cookie_prog.o test_select_reuseport_kern.o \
        test_skb_cgroup_id_kern.o bpf_flow.o netcnt_prog.o \
-       test_sk_lookup_kern.o test_xdp_vlan.o test_queue_map.o test_stack_map.o
+       test_sk_lookup_kern.o test_xdp_vlan.o test_queue_map.o test_stack_map.o \
+       test_map_in_map.o
 
 # Order correspond to 'make run_tests' order
 TEST_PROGS := test_kmod.sh \

diff --git a/tools/testing/selftests/bpf/test_map_in_map.c b/tools/testing/selftests/bpf/test_map_in_map.c
new file mode 100644 (file)
index 0000000..ce923e6
--- /dev/null
+++ b/tools/testing/selftests/bpf/test_map_in_map.c
@@ -0,0 +1,49 @@
+// SPDX-License-Identifier: GPL-2.0
+/* Copyright (c) 2018 Facebook */
+#include <stddef.h>
+#include <linux/bpf.h>
+#include <linux/types.h>
+#include "bpf_helpers.h"
+
+struct bpf_map_def SEC("maps") mim_array = {
+       .type = BPF_MAP_TYPE_ARRAY_OF_MAPS,
+       .key_size = sizeof(int),
+       /* must be sizeof(__u32) for map in map */
+       .value_size = sizeof(__u32),
+       .max_entries = 1,
+       .map_flags = 0,
+};
+
+struct bpf_map_def SEC("maps") mim_hash = {
+       .type = BPF_MAP_TYPE_HASH_OF_MAPS,
+       .key_size = sizeof(int),
+       /* must be sizeof(__u32) for map in map */
+       .value_size = sizeof(__u32),
+       .max_entries = 1,
+       .map_flags = 0,
+};
+
+SEC("xdp_mimtest")
+int xdp_mimtest0(struct xdp_md *ctx)
+{
+       int value = 123;
+       int key = 0;
+       void *map;
+
+       map = bpf_map_lookup_elem(&mim_array, &key);
+       if (!map)
+               return XDP_DROP;
+
+       bpf_map_update_elem(map, &key, &value, 0);
+
+       map = bpf_map_lookup_elem(&mim_hash, &key);
+       if (!map)
+               return XDP_DROP;
+
+       bpf_map_update_elem(map, &key, &value, 0);
+
+       return XDP_PASS;
+}
+
+int _version SEC("version") = 1;
+char _license[] SEC("license") = "GPL";

diff --git a/tools/testing/selftests/bpf/test_maps.c b/tools/testing/selftests/bpf/test_maps.c
index 9f0a5b16a2469e8f76669a0d0d8a6da03cbc77be..9c79ee017df3bf15ac704e765188a4c2a56bf862 100644 (file)
--- a/tools/testing/selftests/bpf/test_maps.c
+++ b/tools/testing/selftests/bpf/test_maps.c
@@ -1125,6 +1125,94 @@ static void test_sockmap(int tasks, void *data)
        exit(1);
 }
 
+#define MAPINMAP_PROG "./test_map_in_map.o"
+static void test_map_in_map(void)
+{
+       struct bpf_program *prog;
+       struct bpf_object *obj;
+       struct bpf_map *map;
+       int mim_fd, fd, err;
+       int pos = 0;
+
+       obj = bpf_object__open(MAPINMAP_PROG);
+
+       fd = bpf_create_map(BPF_MAP_TYPE_HASH, sizeof(int), sizeof(int),
+                           2, 0);
+       if (fd < 0) {
+               printf("Failed to create hashmap '%s'!\n", strerror(errno));
+               exit(1);
+       }
+
+       map = bpf_object__find_map_by_name(obj, "mim_array");
+       if (IS_ERR(map)) {
+               printf("Failed to load array of maps from test prog\n");
+               goto out_map_in_map;
+       }
+       err = bpf_map__set_inner_map_fd(map, fd);
+       if (err) {
+               printf("Failed to set inner_map_fd for array of maps\n");
+               goto out_map_in_map;
+       }
+
+       map = bpf_object__find_map_by_name(obj, "mim_hash");
+       if (IS_ERR(map)) {
+               printf("Failed to load hash of maps from test prog\n");
+               goto out_map_in_map;
+       }
+       err = bpf_map__set_inner_map_fd(map, fd);
+       if (err) {
+               printf("Failed to set inner_map_fd for hash of maps\n");
+               goto out_map_in_map;
+       }
+
+       bpf_object__for_each_program(prog, obj) {
+               bpf_program__set_xdp(prog);
+       }
+       bpf_object__load(obj);
+
+       map = bpf_object__find_map_by_name(obj, "mim_array");
+       if (IS_ERR(map)) {
+               printf("Failed to load array of maps from test prog\n");
+               goto out_map_in_map;
+       }
+       mim_fd = bpf_map__fd(map);
+       if (mim_fd < 0) {
+               printf("Failed to get descriptor for array of maps\n");
+               goto out_map_in_map;
+       }
+
+       err = bpf_map_update_elem(mim_fd, &pos, &fd, 0);
+       if (err) {
+               printf("Failed to update array of maps\n");
+               goto out_map_in_map;
+       }
+
+       map = bpf_object__find_map_by_name(obj, "mim_hash");
+       if (IS_ERR(map)) {
+               printf("Failed to load hash of maps from test prog\n");
+               goto out_map_in_map;
+       }
+       mim_fd = bpf_map__fd(map);
+       if (mim_fd < 0) {
+               printf("Failed to get descriptor for hash of maps\n");
+               goto out_map_in_map;
+       }
+
+       err = bpf_map_update_elem(mim_fd, &pos, &fd, 0);
+       if (err) {
+               printf("Failed to update hash of maps\n");
+               goto out_map_in_map;
+       }
+
+       close(fd);
+       bpf_object__close(obj);
+       return;
+
+out_map_in_map:
+       close(fd);
+       exit(1);
+}
+
 #define MAP_SIZE (32 * 1024)
 
 static void test_map_large(void)
@@ -1600,6 +1688,8 @@ static void run_all_tests(void)
 
        test_queuemap(0, NULL);
        test_stackmap(0, NULL);
+
+       test_map_in_map();
 }
 
 int main(void)