selftests/bpf: add CO-RE relocs enum/ptr/func_proto tests

Test CO-RE relocation handling of ints, enums, pointers, func protos, etc.
Signed-off-by: Andrii Nakryiko <andriin@fb.com>
Acked-by: Song Liu <songliubraving@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>

tools/testing/selftests/bpf/prog_tests/core_reloc.c

@@ -81,6 +81,32 @@
 	.fails = true,							\
 }
 
+#define PRIMITIVES_DATA(struct_name) STRUCT_TO_CHAR_PTR(struct_name) {	\
+	.a = 1,								\
+	.b = 2,								\
+	.c = 3,								\
+	.d = (void *)4,							\
+	.f = (void *)5,							\
+}
+
+#define PRIMITIVES_CASE_COMMON(name)					\
+	.case_name = #name,						\
+	.bpf_obj_file = "test_core_reloc_primitives.o",			\
+	.btf_src_file = "btf__core_reloc_" #name ".o"
+
+#define PRIMITIVES_CASE(name) {						\
+	PRIMITIVES_CASE_COMMON(name),					\
+	.input = PRIMITIVES_DATA(core_reloc_##name),			\
+	.input_len = sizeof(struct core_reloc_##name),			\
+	.output = PRIMITIVES_DATA(core_reloc_primitives),		\
+	.output_len = sizeof(struct core_reloc_primitives),		\
+}
+
+#define PRIMITIVES_ERR_CASE(name) {					\
+	PRIMITIVES_CASE_COMMON(name),					\
+	.fails = true,							\
+}
+
 struct core_reloc_test_case {
 	const char *case_name;
 	const char *bpf_obj_file;
@@ -137,6 +163,16 @@ static struct core_reloc_test_case test_cases[] = {
 	ARRAYS_ERR_CASE(arrays___err_non_array),
 	ARRAYS_ERR_CASE(arrays___err_wrong_val_type1),
 	ARRAYS_ERR_CASE(arrays___err_wrong_val_type2),
+
+	/* enum/ptr/int handling scenarios */
+	PRIMITIVES_CASE(primitives),
+	PRIMITIVES_CASE(primitives___diff_enum_def),
+	PRIMITIVES_CASE(primitives___diff_func_proto),
+	PRIMITIVES_CASE(primitives___diff_ptr_type),
+
+	PRIMITIVES_ERR_CASE(primitives___err_non_enum),
+	PRIMITIVES_ERR_CASE(primitives___err_non_int),
+	PRIMITIVES_ERR_CASE(primitives___err_non_ptr),
 };
 
 struct data {

tools/testing/selftests/bpf/progs/btf__core_reloc_primitives.c

+#include "core_reloc_types.h"
+
+void f(struct core_reloc_primitives x) {}

tools/testing/selftests/bpf/progs/btf__core_reloc_primitives___diff_enum_def.c

+#include "core_reloc_types.h"
+
+void f(struct core_reloc_primitives___diff_enum_def x) {}

tools/testing/selftests/bpf/progs/btf__core_reloc_primitives___diff_func_proto.c

+#include "core_reloc_types.h"
+
+void f(struct core_reloc_primitives___diff_func_proto x) {}

tools/testing/selftests/bpf/progs/btf__core_reloc_primitives___diff_ptr_type.c

+#include "core_reloc_types.h"
+
+void f(struct core_reloc_primitives___diff_ptr_type x) {}

tools/testing/selftests/bpf/progs/btf__core_reloc_primitives___err_non_enum.c

+#include "core_reloc_types.h"
+
+void f(struct core_reloc_primitives___err_non_enum x) {}

tools/testing/selftests/bpf/progs/btf__core_reloc_primitives___err_non_int.c

+#include "core_reloc_types.h"
+
+void f(struct core_reloc_primitives___err_non_int x) {}

tools/testing/selftests/bpf/progs/btf__core_reloc_primitives___err_non_ptr.c

+#include "core_reloc_types.h"
+
+void f(struct core_reloc_primitives___err_non_ptr x) {}

tools/testing/selftests/bpf/progs/core_reloc_types.h

@@ -387,3 +387,70 @@ struct core_reloc_arrays___err_wrong_val_type2 {
 	int c[3]; /* value is not a struct */
 	struct core_reloc_arrays_substruct d[1][2];
 };
+
+/*
+ * PRIMITIVES
+ */
+enum core_reloc_primitives_enum {
+	A = 0,
+	B = 1,
+};
+
+struct core_reloc_primitives {
+	char a;
+	int b;
+	enum core_reloc_primitives_enum c;
+	void *d;
+	int (*f)(const char *);
+};
+
+struct core_reloc_primitives___diff_enum_def {
+	char a;
+	int b;
+	void *d;
+	int (*f)(const char *);
+	enum {
+		X = 100,
+		Y = 200,
+	} c; /* inline enum def with differing set of values */
+};
+
+struct core_reloc_primitives___diff_func_proto {
+	void (*f)(int); /* incompatible function prototype */
+	void *d;
+	enum core_reloc_primitives_enum c;
+	int b;
+	char a;
+};
+
+struct core_reloc_primitives___diff_ptr_type {
+	const char * const d; /* different pointee type + modifiers */
+	char a;
+	int b;
+	enum core_reloc_primitives_enum c;
+	int (*f)(const char *);
+};
+
+struct core_reloc_primitives___err_non_enum {
+	char a[1];
+	int b;
+	int c; /* int instead of enum */
+	void *d;
+	int (*f)(const char *);
+};
+
+struct core_reloc_primitives___err_non_int {
+	char a[1];
+	int *b; /* ptr instead of int */
+	enum core_reloc_primitives_enum c;
+	void *d;
+	int (*f)(const char *);
+};
+
+struct core_reloc_primitives___err_non_ptr {
+	char a[1];
+	int b;
+	enum core_reloc_primitives_enum c;
+	int d; /* int instead of ptr */
+	int (*f)(const char *);
+};

tools/testing/selftests/bpf/progs/test_core_reloc_primitives.c

+// SPDX-License-Identifier: GPL-2.0
+// Copyright (c) 2019 Facebook
+
+#include <linux/bpf.h>
+#include <stdint.h>
+#include "bpf_helpers.h"
+
+char _license[] SEC("license") = "GPL";
+
+static volatile struct data {
+	char in[256];
+	char out[256];
+} data;
+
+enum core_reloc_primitives_enum {
+	A = 0,
+	B = 1,
+};
+
+struct core_reloc_primitives {
+	char a;
+	int b;
+	enum core_reloc_primitives_enum c;
+	void *d;
+	int (*f)(const char *);
+};
+
+SEC("raw_tracepoint/sys_enter")
+int test_core_primitives(void *ctx)
+{
+	struct core_reloc_primitives *in = (void *)&data.in;
+	struct core_reloc_primitives *out = (void *)&data.out;
+
+	if (BPF_CORE_READ(&out->a, &in->a) ||
+	    BPF_CORE_READ(&out->b, &in->b) ||
+	    BPF_CORE_READ(&out->c, &in->c) ||
+	    BPF_CORE_READ(&out->d, &in->d) ||
+	    BPF_CORE_READ(&out->f, &in->f))
+		return 1;
+
+	return 0;
+}
+