// SPDX-License-Identifier: GPL-2.0 /* Copyright (c) 2020 Facebook */ #include #include static char *dump_buf; static size_t dump_buf_sz; static FILE *dump_buf_file; static void btf_dump_printf(void *ctx, const char *fmt, va_list args) { vfprintf(ctx, fmt, args); } /* Write raw BTF to file, return number of bytes written or negative errno */ static ssize_t btf_raw_write(struct btf *btf, char *file) { ssize_t written = 0; const void *data; __u32 size = 0; int fd, ret; fd = mkstemp(file); if (!ASSERT_GE(fd, 0, "create_file")) return -errno; data = btf__raw_data(btf, &size); if (!ASSERT_OK_PTR(data, "btf__raw_data")) { close(fd); return -EINVAL; } while (written < size) { ret = write(fd, data + written, size - written); if (!ASSERT_GE(ret, 0, "write succeeded")) { close(fd); return -errno; } written += ret; } close(fd); return written; } static void __test_btf_split(bool multi) { char multisplit_btf_file[] = "/tmp/test_btf_multisplit.XXXXXX"; char split_btf_file[] = "/tmp/test_btf_split.XXXXXX"; char base_btf_file[] = "/tmp/test_btf_base.XXXXXX"; ssize_t multisplit_btf_sz = 0, split_btf_sz = 0, base_btf_sz = 0; struct btf_dump *d = NULL; const struct btf_type *t, *ot; struct btf *btf1 = NULL, *btf2 = NULL, *btf3 = NULL; struct btf *btf4 = NULL, *btf5 = NULL, *btf6 = NULL; int str_off, i, err; btf1 = btf__new_empty(); if (!ASSERT_OK_PTR(btf1, "empty_main_btf")) return; btf__set_pointer_size(btf1, 8); /* enforce 64-bit arch */ btf__add_int(btf1, "int", 4, BTF_INT_SIGNED); /* [1] int */ btf__add_ptr(btf1, 1); /* [2] ptr to int */ btf__add_struct(btf1, "s1", 4); /* [3] struct s1 { */ btf__add_field(btf1, "f1", 1, 0, 0); /* int f1; */ /* } */ btf2 = btf__new_empty_split(btf1); if (!ASSERT_OK_PTR(btf2, "empty_split_btf")) goto cleanup; /* pointer size should be "inherited" from main BTF */ ASSERT_EQ(btf__pointer_size(btf2), 8, "inherit_ptr_sz"); str_off = btf__find_str(btf2, "int"); ASSERT_NEQ(str_off, -ENOENT, "str_int_missing"); t = btf__type_by_id(btf2, 1); if (!ASSERT_OK_PTR(t, "int_type")) goto cleanup; ASSERT_EQ(btf_is_int(t), true, "int_kind"); ASSERT_STREQ(btf__str_by_offset(btf2, t->name_off), "int", "int_name"); btf__add_struct(btf2, "s2", 16); /* [4] struct s2 { */ btf__add_field(btf2, "f1", 3, 0, 0); /* struct s1 f1; */ btf__add_field(btf2, "f2", 1, 32, 0); /* int f2; */ btf__add_field(btf2, "f3", 2, 64, 0); /* int *f3; */ /* } */ t = btf__type_by_id(btf1, 4); ASSERT_NULL(t, "split_type_in_main"); t = btf__type_by_id(btf2, 4); if (!ASSERT_OK_PTR(t, "split_struct_type")) goto cleanup; ASSERT_EQ(btf_is_struct(t), true, "split_struct_kind"); ASSERT_EQ(btf_vlen(t), 3, "split_struct_vlen"); ASSERT_STREQ(btf__str_by_offset(btf2, t->name_off), "s2", "split_struct_name"); if (multi) { btf3 = btf__new_empty_split(btf2); if (!ASSERT_OK_PTR(btf3, "multi_split_btf")) goto cleanup; } else { btf3 = btf2; } btf__add_union(btf3, "u1", 16); /* [5] union u1 { */ btf__add_field(btf3, "f1", 4, 0, 0); /* struct s2 f1; */ btf__add_field(btf3, "uf2", 1, 0, 0); /* int f2; */ /* } */ if (multi) { t = btf__type_by_id(btf2, 5); ASSERT_NULL(t, "multisplit_type_in_first_split"); } t = btf__type_by_id(btf3, 5); if (!ASSERT_OK_PTR(t, "split_union_type")) goto cleanup; ASSERT_EQ(btf_is_union(t), true, "split_union_kind"); ASSERT_EQ(btf_vlen(t), 2, "split_union_vlen"); ASSERT_STREQ(btf__str_by_offset(btf3, t->name_off), "u1", "split_union_name"); ASSERT_EQ(btf__type_cnt(btf3), 6, "split_type_cnt"); t = btf__type_by_id(btf3, 1); if (!ASSERT_OK_PTR(t, "split_base_type")) goto cleanup; ASSERT_EQ(btf_is_int(t), true, "split_base_int"); ASSERT_STREQ(btf__str_by_offset(btf3, t->name_off), "int", "split_base_type_name"); /* BTF-to-C dump of split BTF */ dump_buf_file = open_memstream(&dump_buf, &dump_buf_sz); if (!ASSERT_OK_PTR(dump_buf_file, "dump_memstream")) return; d = btf_dump__new(btf3, btf_dump_printf, dump_buf_file, NULL); if (!ASSERT_OK_PTR(d, "btf_dump__new")) goto cleanup; for (i = 1; i < btf__type_cnt(btf3); i++) { err = btf_dump__dump_type(d, i); ASSERT_OK(err, "dump_type_ok"); } fflush(dump_buf_file); dump_buf[dump_buf_sz] = 0; /* some libc implementations don't do this */ ASSERT_STREQ(dump_buf, "struct s1 {\n" " int f1;\n" "};\n\n" "struct s2 {\n" " struct s1 f1;\n" " int f2;\n" " int *f3;\n" "};\n\n" "union u1 {\n" " struct s2 f1;\n" " int uf2;\n" "};\n\n", "c_dump"); /* write base, split BTFs to files and ensure parsing succeeds */ base_btf_sz = btf_raw_write(btf1, base_btf_file); if (base_btf_sz < 0) goto cleanup; split_btf_sz = btf_raw_write(btf2, split_btf_file); if (split_btf_sz < 0) goto cleanup; btf4 = btf__parse(base_btf_file, NULL); if (!ASSERT_OK_PTR(btf4, "parse_base")) goto cleanup; btf5 = btf__parse_split(split_btf_file, btf4); if (!ASSERT_OK_PTR(btf5, "parse_split")) goto cleanup; if (multi) { multisplit_btf_sz = btf_raw_write(btf3, multisplit_btf_file); if (multisplit_btf_sz < 0) goto cleanup; btf6 = btf__parse_split(multisplit_btf_file, btf5); if (!ASSERT_OK_PTR(btf6, "parse_multisplit")) goto cleanup; } else { btf6 = btf5; } if (!ASSERT_EQ(btf__type_cnt(btf3), btf__type_cnt(btf6), "cmp_type_cnt")) goto cleanup; /* compare parsed to original BTF */ for (i = 1; i < btf__type_cnt(btf6); i++) { t = btf__type_by_id(btf6, i); if (!ASSERT_OK_PTR(t, "type_in_parsed_btf")) goto cleanup; ot = btf__type_by_id(btf3, i); if (!ASSERT_OK_PTR(ot, "type_in_orig_btf")) goto cleanup; if (!ASSERT_EQ(memcmp(t, ot, sizeof(*ot)), 0, "cmp_parsed_orig_btf")) goto cleanup; } cleanup: if (dump_buf_file) fclose(dump_buf_file); free(dump_buf); btf_dump__free(d); btf__free(btf1); btf__free(btf2); if (btf2 != btf3) btf__free(btf3); btf__free(btf4); btf__free(btf5); if (btf5 != btf6) btf__free(btf6); if (base_btf_sz > 0) unlink(base_btf_file); if (split_btf_sz > 0) unlink(split_btf_file); if (multisplit_btf_sz > 0) unlink(multisplit_btf_file); } void test_btf_split(void) { if (test__start_subtest("single_split")) __test_btf_split(false); if (test__start_subtest("multi_split")) __test_btf_split(true); }