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 | 50 +++++++
.../selftests/bpf/bpf_testmod/bpf_testmod.h | 5 +
.../bpf/prog_tests/test_struct_ops_module.c | 137 ++++++++++++++++++
.../selftests/bpf/progs/struct_ops_module.c | 30 ++++
.../selftests/bpf/progs/testmod_unload.c | 25 ++++
5 files changed, 247 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..25ce13760807 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 +521,59 @@ 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)
+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 +584,7 @@ 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..7ec340bba5d7
--- /dev/null
+++ b/tools/testing/selftests/bpf/prog_tests/test_struct_ops_module.c
@@ -0,0 +1,137 @@
+// 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 int unload_testmod_wait(void)
+{
+ struct testmod_unload *skel_unload;
+ struct bpf_link *link_map_free;
+ int err, i;
+
+ skel_unload = testmod_unload__open_and_load();
+ if (!ASSERT_OK_PTR(skel_unload, "testmod_unload_open"))
+ return -1;
+
+ link_map_free = bpf_program__attach(skel_unload->progs.trace_map_free);
+ if (!ASSERT_OK_PTR(link_map_free, "create_link_map_free")) {
+ testmod_unload__destroy(skel_unload);
+ return -1;
+ }
+
+ /* 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);
+
+ err = unload_bpf_testmod(false);
+ ASSERT_OK(err, "unload_bpf_testmod");
+
+ return err;
+}
+
+static void test_without_testmod(struct bpf_map_info *info)
+{
+ DECLARE_LIBBPF_OPTS(bpf_map_create_opts, map_opts);
+ int err, fd;
+
+ /* Prepare map create opts */
+ fd = bpf_btf_get_fd_by_id(info->btf_id);
+ if (!ASSERT_GT(fd, 0, "get_btf_fd"))
+ goto cleanup;
+ map_opts.btf_fd = fd;
+
+ fd = bpf_btf_get_fd_by_id(info->btf_vmlinux_id);
+ if (!ASSERT_GT(fd, 0, "get_value_type_btf_obj_fd"))
+ goto cleanup;
+ map_opts.value_type_btf_obj_fd = fd;
+
+ map_opts.btf_vmlinux_value_type_id = info->btf_vmlinux_value_type_id;
+
+ /* Create a struct_ops map */
+ fd = bpf_map_create(BPF_MAP_TYPE_STRUCT_OPS, "testmod_success",
+ info->key_size, info->value_size,
+ info->max_entries, &map_opts);
+ if (!ASSERT_GT(fd, 0, "bpf_map_create_testmod_success"))
+ goto cleanup;
+
+ close(fd);
+
+ err = unload_testmod_wait();
+ if (err)
+ goto cleanup;
+
+ /* Create a struct_ops map again while bpf_testmod.ko is
+ * unloaded.
+ */
+ fd = bpf_map_create(BPF_MAP_TYPE_STRUCT_OPS, "testmod_fail",
+ info->key_size, info->value_size,
+ info->max_entries, &map_opts);
+ if (ASSERT_LT(fd, 0, "bpf_map_create_testmod_fail"))
+ close(fd);
+ load_bpf_testmod(false);
+
+cleanup:
+ if (map_opts.btf_fd > 0)
+ close(map_opts.btf_fd);
+ if (map_opts.value_type_btf_obj_fd > 0)
+ close(map_opts.value_type_btf_obj_fd);
+}
+
+static void test_struct_ops_load(void)
+{
+ DECLARE_LIBBPF_OPTS(bpf_object_open_opts, opts);
+ struct struct_ops_module *skel;
+ struct bpf_map_info info = {};
+ struct bpf_link *link;
+ int err;
+ u32 len;
+
+ 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;
+
+ len = sizeof(info);
+ err = bpf_map_get_info_by_fd(bpf_map__fd(skel->maps.testmod_1), &info,
+ &len);
+ if (!ASSERT_OK(err, "bpf_map_get_info_by_fd"))
+ 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:
+ struct_ops_module__destroy(skel);
+
+ test_without_testmod(&info);
+}
+
+void serial_test_struct_ops_module(void)
+{
+ if (test__start_subtest("test_struct_ops_load"))
+ test_struct_ops_load();
+}
+
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
