[PATCH v2 bpf-next 2/4] selftests/bpf: Add bloom filter map test cases

[Joanne Koong <joannekoong@fb.com>]

This patch adds test cases for bpf bloom filter maps. They include tests
checking against invalid operations by userspace, tests for using the bloom
filter map as an inner map, and a bpf program that queries the bloom filter
map for values added by a userspace program.

Signed-off-by: Joanne Koong <joannekoong@fb.com>
---
 .../bpf/prog_tests/bloom_filter_map.c         | 177 ++++++++++++++++++
 .../selftests/bpf/progs/bloom_filter_map.c    |  82 ++++++++
 2 files changed, 259 insertions(+)
 create mode 100644 tools/testing/selftests/bpf/prog_tests/bloom_filter_map.c
 create mode 100644 tools/testing/selftests/bpf/progs/bloom_filter_map.c

diff --git a/tools/testing/selftests/bpf/prog_tests/bloom_filter_map.c b/tools/testing/selftests/bpf/prog_tests/bloom_filter_map.c
new file mode 100644
index 000000000000..eb81aab0d7be
--- /dev/null
+++ b/tools/testing/selftests/bpf/prog_tests/bloom_filter_map.c
@@ -0,0 +1,177 @@
+// SPDX-License-Identifier: GPL-2.0
+/* Copyright (c) 2021 Facebook */
+
+#include <sys/syscall.h>
+#include <test_progs.h>
+#include "bloom_filter_map.skel.h"
+
+static void test_bloom_filter_map_fail(void)
+{
+	struct bpf_create_map_attr xattr = {
+		.name = "bloom_filter_map",
+		.map_type = BPF_MAP_TYPE_BLOOM_FILTER,
+		.max_entries = 100,
+		.value_size = sizeof(__u32),
+		.map_flags = BPF_F_BLOOM_FILTER_HASH_BIT_2,
+	};
+	__u32 value;
+	int fd, err;
+
+	/* Invalid key size */
+	xattr.key_size = 4;
+	fd = bpf_create_map_xattr(&xattr);
+	if (!ASSERT_LT(fd, 0, "bpf_create_map bloom filter invalid key size"))
+		close(fd);
+	xattr.key_size = 0;
+
+	/* Invalid value size */
+	xattr.value_size = 0;
+	fd = bpf_create_map_xattr(&xattr);
+	if (!ASSERT_LT(fd, 0, "bpf_create_map bloom filter invalid value size"))
+		close(fd);
+	xattr.value_size = sizeof(__u32);
+
+	/* Invalid max entries size */
+	xattr.max_entries = 0;
+	fd = bpf_create_map_xattr(&xattr);
+	if (!ASSERT_LT(fd, 0, "bpf_create_map bloom filter invalid max entries size"))
+		close(fd);
+	xattr.max_entries = 100;
+
+	/* Bloom filter maps do not support BPF_F_NO_PREALLOC */
+	xattr.map_flags = BPF_F_NO_PREALLOC;
+	fd = bpf_create_map_xattr(&xattr);
+	if (!ASSERT_LT(fd, 0, "bpf_create_map bloom filter invalid flags"))
+		close(fd);
+	xattr.map_flags = 0;
+
+	fd = bpf_create_map_xattr(&xattr);
+	if (!ASSERT_GE(fd, 0, "bpf_create_map bloom filter"))
+		return;
+
+	/* Test invalid flags */
+	err = bpf_map_update_elem(fd, NULL, &value, -1);
+	ASSERT_EQ(err, -EINVAL, "bpf_map_update_elem bloom filter invalid flags");
+
+	err = bpf_map_update_elem(fd, NULL, &value, BPF_EXIST);
+	ASSERT_EQ(err, -EINVAL, "bpf_map_update_elem bloom filter invalid flags");
+
+	err = bpf_map_update_elem(fd, NULL, &value, BPF_F_LOCK);
+	ASSERT_EQ(err, -EINVAL, "bpf_map_update_elem bloom filter invalid flags");
+
+	err = bpf_map_update_elem(fd, NULL, &value, BPF_NOEXIST);
+	ASSERT_EQ(err, -EINVAL, "bpf_map_update_elem bloom filter invalid flags");
+
+	err = bpf_map_update_elem(fd, NULL, &value, 10000);
+	ASSERT_EQ(err, -EINVAL, "bpf_map_update_elem bloom filter invalid flags");
+
+	close(fd);
+}
+
+static void bloom_filter_map(struct bloom_filter_map *skel)
+{
+	const int map_size = bpf_map__max_entries(skel->maps.map_random_data);
+	int err, map_random_data_fd, map_bloom_filter_fd, i;
+	__u64 val;
+	struct bpf_link *link;
+
+	map_random_data_fd = bpf_map__fd(skel->maps.map_random_data);
+	map_bloom_filter_fd = bpf_map__fd(skel->maps.map_bloom_filter);
+
+	/* Generate random values and add them to the maps */
+	for (i = 0; i < map_size; i++) {
+		val = rand();
+		err = bpf_map_update_elem(map_random_data_fd, &i, &val, BPF_ANY);
+		if (!ASSERT_OK(err, "Add random value to map_random_data"))
+			continue;
+
+		err = bpf_map_update_elem(map_bloom_filter_fd, NULL, &val, 0);
+		if (!ASSERT_OK(err, "Add random value to map_bloom_filter"))
+			return;
+	}
+
+	link = bpf_program__attach(skel->progs.prog_bloom_filter);
+	if (!ASSERT_OK_PTR(link, "link"))
+		return;
+
+	syscall(SYS_getpgid);
+
+	ASSERT_EQ(skel->bss->error, 0, "error");
+
+	bpf_link__destroy(link);
+}
+
+static void bloom_filter_inner_map(struct bloom_filter_map *skel)
+{
+	const int map_size = bpf_map__max_entries(skel->maps.map_random_data);
+	int outer_map_fd, inner_map_fd, map_random_data_fd, err, i, key = 0;
+	struct bpf_create_map_attr xattr = {
+		.name = "bloom_filter_inner_map",
+		.map_type = BPF_MAP_TYPE_BLOOM_FILTER,
+		.max_entries = map_size,
+		.value_size = sizeof(__u64),
+	};
+	struct bpf_link *link;
+	__u64 val;
+
+	/* Create a bloom filter map that will be used as the inner map */
+	inner_map_fd = bpf_create_map_xattr(&xattr);
+	if (!ASSERT_GE(inner_map_fd, 0, "bpf_create_map bloom filter map as inner map"))
+		return;
+
+	/* Generate random values and add them to the maps */
+	map_random_data_fd = bpf_map__fd(skel->maps.map_random_data);
+	for (i = 0; i < map_size; i++) {
+		val = rand();
+		err = bpf_map_update_elem(map_random_data_fd, &i, &val, BPF_ANY);
+		if (!ASSERT_OK(err, "Add random value to map_random_data"))
+			continue;
+
+		err = bpf_map_update_elem(inner_map_fd, NULL, &val, 0);
+		if (!ASSERT_OK(err, "Add random value to inner_map_fd"))
+			goto done;
+	}
+
+	outer_map_fd = bpf_map__fd(skel->maps.outer_map);
+	/* Add the bloom filter map to the outer map */
+	err = bpf_map_update_elem(outer_map_fd, &key, &inner_map_fd, 0);
+	if (!ASSERT_OK(err, "Add bloom filter map to outer map"))
+		goto done;
+
+	/* Attach the bloom_filter_inner_map prog */
+	link = bpf_program__attach(skel->progs.prog_bloom_filter_inner_map);
+	if (!ASSERT_OK_PTR(link, "link"))
+		goto delete_inner_map;
+
+	syscall(SYS_getpgid);
+
+	ASSERT_EQ(skel->bss->error, 0, "error");
+
+	bpf_link__destroy(link);
+
+delete_inner_map:
+	/* Ensure the inner bloom filter map can be deleted */
+	err = bpf_map_delete_elem(outer_map_fd, &key);
+	ASSERT_OK(err, "Delete inner bloom filter map");
+
+done:
+	close(inner_map_fd);
+}
+
+void test_bloom_filter_map(void)
+{
+	struct bloom_filter_map *skel;
+
+	test_bloom_filter_map_fail();
+
+	skel = bloom_filter_map__open_and_load();
+	if (!ASSERT_OK_PTR(skel, "bloom_filter_map__open_and_load"))
+		goto cleanup;
+
+	bloom_filter_map(skel);
+
+	bloom_filter_inner_map(skel);
+
+cleanup:
+	bloom_filter_map__destroy(skel);
+}
diff --git a/tools/testing/selftests/bpf/progs/bloom_filter_map.c b/tools/testing/selftests/bpf/progs/bloom_filter_map.c
new file mode 100644
index 000000000000..8b5bf8d61a40
--- /dev/null
+++ b/tools/testing/selftests/bpf/progs/bloom_filter_map.c
@@ -0,0 +1,82 @@
+// SPDX-License-Identifier: GPL-2.0
+/* Copyright (c) 2021 Facebook */
+
+#include <linux/bpf.h>
+#include <bpf/bpf_helpers.h>
+
+char _license[] SEC("license") = "GPL";
+
+struct bpf_map;
+
+struct {
+	__uint(type, BPF_MAP_TYPE_ARRAY);
+	__uint(max_entries, 1000);
+	__type(key, __u32);
+	__type(value, __u64);
+} map_random_data SEC(".maps");
+
+struct map_bloom_filter_type {
+	__uint(type, BPF_MAP_TYPE_BLOOM_FILTER);
+	__uint(key_size, 0);
+	__uint(value_size, sizeof(__u64));
+	__uint(max_entries, 1000);
+} map_bloom_filter SEC(".maps");
+
+struct {
+	__uint(type, BPF_MAP_TYPE_ARRAY_OF_MAPS);
+	__uint(max_entries, 1);
+	__uint(key_size, sizeof(int));
+	__uint(value_size, sizeof(int));
+	__array(values, struct map_bloom_filter_type);
+} outer_map SEC(".maps");
+
+struct callback_ctx {
+	struct map_bloom_filter_type *map;
+};
+
+int error = 0;
+
+static __u64
+check_elem(struct bpf_map *map, __u32 *key, __u64 *val,
+	   struct callback_ctx *data)
+{
+	int err;
+
+	err = bpf_map_peek_elem(data->map, val);
+	if (err) {
+		error |= 1;
+		return 1; /* stop the iteration */
+	}
+
+	return 0;
+}
+
+SEC("fentry/__x64_sys_getpgid")
+int prog_bloom_filter(void *ctx)
+{
+	struct callback_ctx data;
+
+	data.map = &map_bloom_filter;
+	bpf_for_each_map_elem(&map_random_data, check_elem, &data, 0);
+
+	return 0;
+}
+
+SEC("fentry/__x64_sys_getpgid")
+int prog_bloom_filter_inner_map(void *ctx)
+{
+	struct map_bloom_filter_type *inner_map;
+	struct callback_ctx data;
+	int key = 0;
+
+	inner_map = bpf_map_lookup_elem(&outer_map, &key);
+	if (!inner_map) {
+		error |= 2;
+		return 0;
+	}
+
+	data.map = inner_map;
+	bpf_for_each_map_elem(&map_random_data, check_elem, &data, 0);
+
+	return 0;
+}
-- 
2.30.2