From: Kui-Feng Lee <thinker.li@xxxxxxxxx> Create a new struct_ops type called bpf_testmod_ops within the bpf_testmod module. When a struct_ops object is registered, the bpf_testmod module will invoke test_2 from the module. Signed-off-by: Kui-Feng Lee <thinker.li@xxxxxxxxx> --- .../selftests/bpf/bpf_testmod/bpf_testmod.c | 52 +++++++++++ .../selftests/bpf/bpf_testmod/bpf_testmod.h | 5 + .../bpf/prog_tests/test_struct_ops_module.c | 92 +++++++++++++++++++ .../selftests/bpf/progs/struct_ops_module.c | 30 ++++++ .../selftests/bpf/progs/testmod_unload.c | 25 +++++ 5 files changed, 204 insertions(+) create mode 100644 tools/testing/selftests/bpf/prog_tests/test_struct_ops_module.c create mode 100644 tools/testing/selftests/bpf/progs/struct_ops_module.c create mode 100644 tools/testing/selftests/bpf/progs/testmod_unload.c diff --git a/tools/testing/selftests/bpf/bpf_testmod/bpf_testmod.c b/tools/testing/selftests/bpf/bpf_testmod/bpf_testmod.c index 91907b321f91..804a67bbb479 100644 --- a/tools/testing/selftests/bpf/bpf_testmod/bpf_testmod.c +++ b/tools/testing/selftests/bpf/bpf_testmod/bpf_testmod.c @@ -1,5 +1,6 @@ // SPDX-License-Identifier: GPL-2.0 /* Copyright (c) 2020 Facebook */ +#include <linux/bpf.h> #include <linux/btf.h> #include <linux/btf_ids.h> #include <linux/error-injection.h> @@ -520,11 +521,61 @@ BTF_ID_FLAGS(func, bpf_kfunc_call_test_static_unused_arg) BTF_ID_FLAGS(func, bpf_kfunc_call_test_offset) BTF_SET8_END(bpf_testmod_check_kfunc_ids) +DEFINE_STRUCT_OPS_VALUE_TYPE(bpf_testmod_ops); + +static int bpf_testmod_ops_init(struct btf *btf) +{ + return 0; +} + +static bool bpf_testmod_ops_is_valid_access(int off, int size, + enum bpf_access_type type, + const struct bpf_prog *prog, + struct bpf_insn_access_aux *info) +{ + return bpf_tracing_btf_ctx_access(off, size, type, prog, info); +} + +static int bpf_testmod_ops_init_member(const struct btf_type *t, + const struct btf_member *member, + void *kdata, const void *udata) +{ + return 0; +} + static const struct btf_kfunc_id_set bpf_testmod_kfunc_set = { .owner = THIS_MODULE, .set = &bpf_testmod_check_kfunc_ids, }; +static const struct bpf_verifier_ops bpf_testmod_verifier_ops = { + .is_valid_access = bpf_testmod_ops_is_valid_access, +}; + +static int bpf_dummy_reg(void *kdata) +{ + struct bpf_testmod_ops *ops = kdata; + int r; + + r = ops->test_2(4, 3); + + return 0; +} + +static void bpf_dummy_unreg(void *kdata) +{ +} + +struct bpf_struct_ops bpf_bpf_testmod_ops = { + .verifier_ops = &bpf_testmod_verifier_ops, + .init = bpf_testmod_ops_init, + .init_member = bpf_testmod_ops_init_member, + .reg = bpf_dummy_reg, + .unreg = bpf_dummy_unreg, + .name = "bpf_testmod_ops", + .owner = THIS_MODULE, +}; + extern int bpf_fentry_test1(int a); static int bpf_testmod_init(void) @@ -535,6 +586,7 @@ static int bpf_testmod_init(void) ret = ret ?: register_btf_kfunc_id_set(BPF_PROG_TYPE_SCHED_CLS, &bpf_testmod_kfunc_set); ret = ret ?: register_btf_kfunc_id_set(BPF_PROG_TYPE_TRACING, &bpf_testmod_kfunc_set); ret = ret ?: register_btf_kfunc_id_set(BPF_PROG_TYPE_SYSCALL, &bpf_testmod_kfunc_set); + ret = ret ?: REGISTER_BPF_STRUCT_OPS(&bpf_bpf_testmod_ops, bpf_testmod_ops); if (ret < 0) return ret; if (bpf_fentry_test1(0) < 0) diff --git a/tools/testing/selftests/bpf/bpf_testmod/bpf_testmod.h b/tools/testing/selftests/bpf/bpf_testmod/bpf_testmod.h index f32793efe095..ca5435751c79 100644 --- a/tools/testing/selftests/bpf/bpf_testmod/bpf_testmod.h +++ b/tools/testing/selftests/bpf/bpf_testmod/bpf_testmod.h @@ -28,4 +28,9 @@ struct bpf_iter_testmod_seq { int cnt; }; +struct bpf_testmod_ops { + int (*test_1)(void); + int (*test_2)(int a, int b); +}; + #endif /* _BPF_TESTMOD_H */ diff --git a/tools/testing/selftests/bpf/prog_tests/test_struct_ops_module.c b/tools/testing/selftests/bpf/prog_tests/test_struct_ops_module.c new file mode 100644 index 000000000000..55a4c6ed92aa --- /dev/null +++ b/tools/testing/selftests/bpf/prog_tests/test_struct_ops_module.c @@ -0,0 +1,92 @@ +// SPDX-License-Identifier: GPL-2.0 +/* Copyright (c) 2023 Meta Platforms, Inc. and affiliates. */ +#include <test_progs.h> +#include <time.h> + +#include "struct_ops_module.skel.h" +#include "testmod_unload.skel.h" + +static void test_regular_load(void) +{ + DECLARE_LIBBPF_OPTS(bpf_object_open_opts, opts); + struct struct_ops_module *skel; + struct testmod_unload *skel_unload; + struct bpf_link *link_map_free = NULL; + struct bpf_link *link; + int err, i; + + skel = struct_ops_module__open_opts(&opts); + if (!ASSERT_OK_PTR(skel, "struct_ops_module_open")) + return; + + err = struct_ops_module__load(skel); + if (!ASSERT_OK(err, "struct_ops_module_load")) + goto cleanup; + + link = bpf_map__attach_struct_ops(skel->maps.testmod_1); + ASSERT_OK_PTR(link, "attach_test_mod_1"); + + /* test_2() will be called from bpf_dummy_reg() in bpf_testmod.c */ + ASSERT_EQ(skel->bss->test_2_result, 7, "test_2_result"); + + bpf_link__destroy(link); + +cleanup: + skel_unload = testmod_unload__open_and_load(); + + if (ASSERT_OK_PTR(skel_unload, "testmod_unload_open")) + link_map_free = bpf_program__attach(skel_unload->progs.trace_map_free); + struct_ops_module__destroy(skel); + + if (!ASSERT_OK_PTR(link_map_free, "create_link_map_free")) + return; + + /* Wait for the struct_ops map to be freed. Struct_ops maps hold a + * refcount to the module btf. And, this function unloads and then + * loads bpf_testmod. Without waiting the map to be freed, the next + * test may fail to unload the bpf_testmod module since the map is + * still holding a refcnt to the module. + */ + for (i = 0; i < 10; i++) { + if (skel_unload->bss->bpf_testmod_put) + break; + usleep(100000); + } + ASSERT_EQ(skel_unload->bss->bpf_testmod_put, 1, "map_free"); + + bpf_link__destroy(link_map_free); + testmod_unload__destroy(skel_unload); +} + +static void test_load_without_module(void) +{ + DECLARE_LIBBPF_OPTS(bpf_object_open_opts, opts); + struct struct_ops_module *skel; + int err; + + err = unload_bpf_testmod(false); + if (!ASSERT_OK(err, "unload_bpf_testmod")) + return; + + skel = struct_ops_module__open_opts(&opts); + if (!ASSERT_OK_PTR(skel, "struct_ops_module_open")) + goto cleanup; + err = struct_ops_module__load(skel); + ASSERT_ERR(err, "struct_ops_module_load"); + + struct_ops_module__destroy(skel); + +cleanup: + /* Without this, the next test may fail */ + load_bpf_testmod(false); +} + +void serial_test_struct_ops_module(void) +{ + if (test__start_subtest("regular_load")) + test_regular_load(); + + if (test__start_subtest("load_without_module")) + test_load_without_module(); +} + diff --git a/tools/testing/selftests/bpf/progs/struct_ops_module.c b/tools/testing/selftests/bpf/progs/struct_ops_module.c new file mode 100644 index 000000000000..cb305d04342f --- /dev/null +++ b/tools/testing/selftests/bpf/progs/struct_ops_module.c @@ -0,0 +1,30 @@ +// SPDX-License-Identifier: GPL-2.0 +/* Copyright (c) 2023 Meta Platforms, Inc. and affiliates. */ +#include <vmlinux.h> +#include <bpf/bpf_helpers.h> +#include <bpf/bpf_tracing.h> +#include "../bpf_testmod/bpf_testmod.h" + +char _license[] SEC("license") = "GPL"; + +int test_2_result = 0; + +SEC("struct_ops/test_1") +int BPF_PROG(test_1) +{ + return 0xdeadbeef; +} + +SEC("struct_ops/test_2") +int BPF_PROG(test_2, int a, int b) +{ + test_2_result = a + b; + return a + b; +} + +SEC(".struct_ops.link") +struct bpf_testmod_ops testmod_1 = { + .test_1 = (void *)test_1, + .test_2 = (void *)test_2, +}; + diff --git a/tools/testing/selftests/bpf/progs/testmod_unload.c b/tools/testing/selftests/bpf/progs/testmod_unload.c new file mode 100644 index 000000000000..bb17914ecca3 --- /dev/null +++ b/tools/testing/selftests/bpf/progs/testmod_unload.c @@ -0,0 +1,25 @@ +// SPDX-License-Identifier: GPL-2.0 +/* Copyright (c) 2023 Meta Platforms, Inc. and affiliates. */ +#include <vmlinux.h> +#include <bpf/bpf_core_read.h> +#include <bpf/bpf_tracing.h> + +char _license[] SEC("license") = "GPL"; + +int bpf_testmod_put = 0; + +SEC("fentry/__bpf_struct_ops_map_free") +int BPF_PROG(trace_map_free, struct bpf_map *map) +{ + static const char name[] = "testmod_1"; + int i; + + for (i = 0; i < sizeof(name); i++) { + if (map->name[i] != name[i]) + return 0; + } + + bpf_testmod_put = 1; + + return 0; +} -- 2.34.1