selftests/bpf: Test TYPE_EXISTS and TYPE_SIZE CO-RE relocations

Add selftests for TYPE_EXISTS and TYPE_SIZE relocations, testing correctness
of relocations and handling of type compatiblity/incompatibility.

If __builtin_preserve_type_info() is not supported by compiler, skip tests.

Signed-off-by: Andrii Nakryiko <andriin@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Yonghong Song <yhs@fb.com>
Link: https://lore.kernel.org/bpf/20200819194519.3375898-3-andriin@fb.com

1 files changed, 104 insertions, 21 deletions

diff --git a/tools/testing/selftests/bpf/prog_tests/core_reloc.c b/tools/testing/selftests/bpf/prog_tests/core_reloc.c
index 4d650e99be28..b775ce0ede41 100644
--- a/tools/testing/selftests/bpf/prog_tests/core_reloc.c
+++ b/tools/testing/selftests/bpf/prog_tests/core_reloc.c
@@ -177,14 +177,13 @@
 	.fails = true,							\
 }
 
-#define EXISTENCE_CASE_COMMON(name)					\
+#define FIELD_EXISTS_CASE_COMMON(name)					\
 	.case_name = #name,						\
 	.bpf_obj_file = "test_core_reloc_existence.o",			\
-	.btf_src_file = "btf__core_reloc_" #name ".o",			\
-	.relaxed_core_relocs = true
+	.btf_src_file = "btf__core_reloc_" #name ".o"			\
 
-#define EXISTENCE_ERR_CASE(name) {					\
-	EXISTENCE_CASE_COMMON(name),					\
+#define FIELD_EXISTS_ERR_CASE(name) {					\
+	FIELD_EXISTS_CASE_COMMON(name),					\
 	.fails = true,							\
 }
 
@@ -253,6 +252,23 @@
 	.fails = true,							\
 }
 
+#define TYPE_BASED_CASE_COMMON(name)					\
+	.case_name = #name,						\
+	.bpf_obj_file = "test_core_reloc_type_based.o",		\
+	.btf_src_file = "btf__core_reloc_" #name ".o"			\
+
+#define TYPE_BASED_CASE(name, ...) {					\
+	TYPE_BASED_CASE_COMMON(name),					\
+	.output = STRUCT_TO_CHAR_PTR(core_reloc_type_based_output)	\
+			__VA_ARGS__,					\
+	.output_len = sizeof(struct core_reloc_type_based_output),	\
+}
+
+#define TYPE_BASED_ERR_CASE(name) {					\
+	TYPE_BASED_CASE_COMMON(name),					\
+	.fails = true,							\
+}
+
 struct core_reloc_test_case {
 	const char *case_name;
 	const char *bpf_obj_file;
@@ -364,7 +380,7 @@ static struct core_reloc_test_case test_cases[] = {
 
 	/* validate field existence checks */
 	{
-		EXISTENCE_CASE_COMMON(existence),
+		FIELD_EXISTS_CASE_COMMON(existence),
 		.input = STRUCT_TO_CHAR_PTR(core_reloc_existence) {
 			.a = 1,
 			.b = 2,
@@ -388,7 +404,7 @@ static struct core_reloc_test_case test_cases[] = {
 		.output_len = sizeof(struct core_reloc_existence_output),
 	},
 	{
-		EXISTENCE_CASE_COMMON(existence___minimal),
+		FIELD_EXISTS_CASE_COMMON(existence___minimal),
 		.input = STRUCT_TO_CHAR_PTR(core_reloc_existence___minimal) {
 			.a = 42,
 		},
@@ -408,12 +424,12 @@ static struct core_reloc_test_case test_cases[] = {
 		.output_len = sizeof(struct core_reloc_existence_output),
 	},
 
-	EXISTENCE_ERR_CASE(existence__err_int_sz),
-	EXISTENCE_ERR_CASE(existence__err_int_type),
-	EXISTENCE_ERR_CASE(existence__err_int_kind),
-	EXISTENCE_ERR_CASE(existence__err_arr_kind),
-	EXISTENCE_ERR_CASE(existence__err_arr_value_type),
-	EXISTENCE_ERR_CASE(existence__err_struct_type),
+	FIELD_EXISTS_ERR_CASE(existence__err_int_sz),
+	FIELD_EXISTS_ERR_CASE(existence__err_int_type),
+	FIELD_EXISTS_ERR_CASE(existence__err_int_kind),
+	FIELD_EXISTS_ERR_CASE(existence__err_arr_kind),
+	FIELD_EXISTS_ERR_CASE(existence__err_arr_value_type),
+	FIELD_EXISTS_ERR_CASE(existence__err_struct_type),
 
 	/* bitfield relocation checks */
 	BITFIELDS_CASE(bitfields, {
@@ -453,11 +469,73 @@ static struct core_reloc_test_case test_cases[] = {
 	SIZE_CASE(size),
 	SIZE_CASE(size___diff_sz),
 	SIZE_ERR_CASE(size___err_ambiguous),
+
+	/* validate type existence and size relocations */
+	TYPE_BASED_CASE(type_based, {
+		.struct_exists = 1,
+		.union_exists = 1,
+		.enum_exists = 1,
+		.typedef_named_struct_exists = 1,
+		.typedef_anon_struct_exists = 1,
+		.typedef_struct_ptr_exists = 1,
+		.typedef_int_exists = 1,
+		.typedef_enum_exists = 1,
+		.typedef_void_ptr_exists = 1,
+		.typedef_func_proto_exists = 1,
+		.typedef_arr_exists = 1,
+		.struct_sz = sizeof(struct a_struct),
+		.union_sz = sizeof(union a_union),
+		.enum_sz = sizeof(enum an_enum),
+		.typedef_named_struct_sz = sizeof(named_struct_typedef),
+		.typedef_anon_struct_sz = sizeof(anon_struct_typedef),
+		.typedef_struct_ptr_sz = sizeof(struct_ptr_typedef),
+		.typedef_int_sz = sizeof(int_typedef),
+		.typedef_enum_sz = sizeof(enum_typedef),
+		.typedef_void_ptr_sz = sizeof(void_ptr_typedef),
+		.typedef_func_proto_sz = sizeof(func_proto_typedef),
+		.typedef_arr_sz = sizeof(arr_typedef),
+	}),
+	TYPE_BASED_CASE(type_based___all_missing, {
+		/* all zeros */
+	}),
+	TYPE_BASED_CASE(type_based___diff_sz, {
+		.struct_exists = 1,
+		.union_exists = 1,
+		.enum_exists = 1,
+		.typedef_named_struct_exists = 1,
+		.typedef_anon_struct_exists = 1,
+		.typedef_struct_ptr_exists = 1,
+		.typedef_int_exists = 1,
+		.typedef_enum_exists = 1,
+		.typedef_void_ptr_exists = 1,
+		.typedef_func_proto_exists = 1,
+		.typedef_arr_exists = 1,
+		.struct_sz = sizeof(struct a_struct___diff_sz),
+		.union_sz = sizeof(union a_union___diff_sz),
+		.enum_sz = sizeof(enum an_enum___diff_sz),
+		.typedef_named_struct_sz = sizeof(named_struct_typedef___diff_sz),
+		.typedef_anon_struct_sz = sizeof(anon_struct_typedef___diff_sz),
+		.typedef_struct_ptr_sz = sizeof(struct_ptr_typedef___diff_sz),
+		.typedef_int_sz = sizeof(int_typedef___diff_sz),
+		.typedef_enum_sz = sizeof(enum_typedef___diff_sz),
+		.typedef_void_ptr_sz = sizeof(void_ptr_typedef___diff_sz),
+		.typedef_func_proto_sz = sizeof(func_proto_typedef___diff_sz),
+		.typedef_arr_sz = sizeof(arr_typedef___diff_sz),
+	}),
+	TYPE_BASED_CASE(type_based___incompat, {
+		.enum_exists = 1,
+		.enum_sz = sizeof(enum an_enum),
+	}),
+	TYPE_BASED_CASE(type_based___fn_wrong_args, {
+		.struct_exists = 1,
+		.struct_sz = sizeof(struct a_struct),
+	}),
 };
 
 struct data {
 	char in[256];
 	char out[256];
+	bool skip;
 	uint64_t my_pid_tgid;
 };
 
@@ -516,15 +594,10 @@ void test_core_reloc(void)
 		load_attr.log_level = 0;
 		load_attr.target_btf_path = test_case->btf_src_file;
 		err = bpf_object__load_xattr(&load_attr);
-		if (test_case->fails) {
-			CHECK(!err, "obj_load_fail",
-			      "should fail to load prog '%s'\n", probe_name);
+		if (err) {
+			if (!test_case->fails)
+				CHECK(false, "obj_load", "failed to load prog '%s': %d\n", probe_name, err);
 			goto cleanup;
-		} else {
-			if (CHECK(err, "obj_load",
-				  "failed to load prog '%s': %d\n",
-				  probe_name, err))
-				goto cleanup;
 		}
 
 		data_map = bpf_object__find_map_by_name(obj, "test_cor.bss");
@@ -552,6 +625,16 @@ void test_core_reloc(void)
 		/* trigger test run */
 		usleep(1);
 
+		if (data->skip) {
+			test__skip();
+			goto cleanup;
+		}
+
+		if (test_case->fails) {
+			CHECK(false, "obj_load_fail", "should fail to load prog '%s'\n", probe_name);
+			goto cleanup;
+		}
+
 		equal = memcmp(data->out, test_case->output,
 			       test_case->output_len) == 0;
 		if (CHECK(!equal, "check_result",