1 files changed, 95 insertions, 0 deletions
diff --git a/tools/testing/selftests/bpf/progs/for_each_hash_map_elem.c b/tools/testing/selftests/bpf/progs/for_each_hash_map_elem.c
new file mode 100644
index 000000000000..276994d5c0c7
--- /dev/null
+++ b/tools/testing/selftests/bpf/progs/for_each_hash_map_elem.c
@@ -0,0 +1,95 @@
+// SPDX-License-Identifier: GPL-2.0
+/* Copyright (c) 2021 Facebook */
+#include "vmlinux.h"
+#include <bpf/bpf_helpers.h>
+
+char _license[] SEC("license") = "GPL";
+
+struct {
+	__uint(type, BPF_MAP_TYPE_HASH);
+	__uint(max_entries, 3);
+	__type(key, __u32);
+	__type(value, __u64);
+} hashmap SEC(".maps");
+
+struct {
+	__uint(type, BPF_MAP_TYPE_PERCPU_HASH);
+	__uint(max_entries, 1);
+	__type(key, __u32);
+	__type(value, __u64);
+} percpu_map SEC(".maps");
+
+struct callback_ctx {
+	struct __sk_buff *ctx;
+	int input;
+	int output;
+};
+
+static __u64
+check_hash_elem(struct bpf_map *map, __u32 *key, __u64 *val,
+		struct callback_ctx *data)
+{
+	struct __sk_buff *skb = data->ctx;
+	__u32 k;
+	__u64 v;
+
+	if (skb) {
+		k = *key;
+		v = *val;
+		if (skb->len == 10000 && k == 10 && v == 10)
+			data->output = 3; /* impossible path */
+		else
+			data->output = 4;
+	} else {
+		data->output = data->input;
+		bpf_map_delete_elem(map, key);
+	}
+
+	return 0;
+}
+
+__u32 cpu = 0;
+__u32 percpu_called = 0;
+__u32 percpu_key = 0;
+__u64 percpu_val = 0;
+int percpu_output = 0;
+
+static __u64
+check_percpu_elem(struct bpf_map *map, __u32 *key, __u64 *val,
+		  struct callback_ctx *unused)
+{
+	struct callback_ctx data;
+
+	percpu_called++;
+	cpu = bpf_get_smp_processor_id();
+	percpu_key = *key;
+	percpu_val = *val;
+
+	data.ctx = 0;
+	data.input = 100;
+	data.output = 0;
+	bpf_for_each_map_elem(&hashmap, check_hash_elem, &data, 0);
+	percpu_output = data.output;
+
+	return 0;
+}
+
+int hashmap_output = 0;
+int hashmap_elems = 0;
+int percpu_map_elems = 0;
+
+SEC("tc")
+int test_pkt_access(struct __sk_buff *skb)
+{
+	struct callback_ctx data;
+
+	data.ctx = skb;
+	data.input = 10;
+	data.output = 0;
+	hashmap_elems = bpf_for_each_map_elem(&hashmap, check_hash_elem, &data, 0);
+	hashmap_output = data.output;
+
+	percpu_map_elems = bpf_for_each_map_elem(&percpu_map, check_percpu_elem,
+						 (void *)0, 0);
+	return 0;
+}