1 files changed, 50 insertions, 0 deletions
diff --git a/tools/testing/selftests/bpf/progs/test_core_read_macros.c b/tools/testing/selftests/bpf/progs/test_core_read_macros.c
new file mode 100644
index 000000000000..fd54caa17319
--- /dev/null
+++ b/tools/testing/selftests/bpf/progs/test_core_read_macros.c
@@ -0,0 +1,50 @@
+// SPDX-License-Identifier: GPL-2.0
+// Copyright (c) 2020 Facebook
+
+#include "vmlinux.h"
+#include <bpf/bpf_helpers.h>
+#include <bpf/bpf_core_read.h>
+
+char _license[] SEC("license") = "GPL";
+
+/* shuffled layout for relocatable (CO-RE) reads */
+struct callback_head___shuffled {
+	void (*func)(struct callback_head___shuffled *head);
+	struct callback_head___shuffled *next;
+};
+
+struct callback_head k_probe_in = {};
+struct callback_head___shuffled k_core_in = {};
+
+struct callback_head *u_probe_in = 0;
+struct callback_head___shuffled *u_core_in = 0;
+
+long k_probe_out = 0;
+long u_probe_out = 0;
+
+long k_core_out = 0;
+long u_core_out = 0;
+
+int my_pid = 0;
+
+SEC("raw_tracepoint/sys_enter")
+int handler(void *ctx)
+{
+	int pid = bpf_get_current_pid_tgid() >> 32;
+
+	if (my_pid != pid)
+		return 0;
+
+	/* next pointers for kernel address space have to be initialized from
+	 * BPF side, user-space mmaped addresses are stil user-space addresses
+	 */
+	k_probe_in.next = &k_probe_in;
+	__builtin_preserve_access_index(({k_core_in.next = &k_core_in;}));
+
+	k_probe_out = (long)BPF_PROBE_READ(&k_probe_in, next, next, func);
+	k_core_out = (long)BPF_CORE_READ(&k_core_in, next, next, func);
+	u_probe_out = (long)BPF_PROBE_READ_USER(u_probe_in, next, next, func);
+	u_core_out = (long)BPF_CORE_READ_USER(u_core_in, next, next, func);
+
+	return 0;
+}