bpf/selftests: Verify struct_ops prog sleepable behavior

In a set of prior changes, we added the ability for struct_ops programs
to be sleepable. This patch enhances the dummy_st_ops selftest suite to
validate this behavior by adding a new sleepable struct_ops entry to
dummy_st_ops.

Signed-off-by: David Vernet <void@manifault.com>
Link: https://lore.kernel.org/r/20230125164735.785732-5-void@manifault.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>

diff --git a/include/linux/bpf.h b/include/linux/bpf.h
index 0d868ef..14a0264 100644 (file)
--- a/include/linux/bpf.h
+++ b/include/linux/bpf.h
@@ -1474,6 +1474,7 @@ struct bpf_dummy_ops {
        int (*test_1)(struct bpf_dummy_ops_state *cb);
        int (*test_2)(struct bpf_dummy_ops_state *cb, int a1, unsigned short a2,
                      char a3, unsigned long a4);
+       int (*test_sleepable)(struct bpf_dummy_ops_state *cb);
 };
 
 int bpf_struct_ops_test_run(struct bpf_prog *prog, const union bpf_attr *kattr,

diff --git a/net/bpf/bpf_dummy_struct_ops.c b/net/bpf/bpf_dummy_struct_ops.c
index 1ac4467..ff4f89a 100644 (file)
--- a/net/bpf/bpf_dummy_struct_ops.c
+++ b/net/bpf/bpf_dummy_struct_ops.c
@@ -154,6 +154,23 @@ static bool bpf_dummy_ops_is_valid_access(int off, int size,
        return bpf_tracing_btf_ctx_access(off, size, type, prog, info);
 }
 
+static int bpf_dummy_ops_check_member(const struct btf_type *t,
+                                     const struct btf_member *member,
+                                     const struct bpf_prog *prog)
+{
+       u32 moff = __btf_member_bit_offset(t, member) / 8;
+
+       switch (moff) {
+       case offsetof(struct bpf_dummy_ops, test_sleepable):
+               break;
+       default:
+               if (prog->aux->sleepable)
+                       return -EINVAL;
+       }
+
+       return 0;
+}
+
 static int bpf_dummy_ops_btf_struct_access(struct bpf_verifier_log *log,
                                           const struct bpf_reg_state *reg,
                                           int off, int size, enum bpf_access_type atype,
@@ -208,6 +225,7 @@ static void bpf_dummy_unreg(void *kdata)
 struct bpf_struct_ops bpf_bpf_dummy_ops = {
        .verifier_ops = &bpf_dummy_verifier_ops,
        .init = bpf_dummy_init,
+       .check_member = bpf_dummy_ops_check_member,
        .init_member = bpf_dummy_init_member,
        .reg = bpf_dummy_reg,
        .unreg = bpf_dummy_unreg,

diff --git a/tools/testing/selftests/bpf/prog_tests/dummy_st_ops.c b/tools/testing/selftests/bpf/prog_tests/dummy_st_ops.c
index c118326..f43fcb1 100644 (file)
--- a/tools/testing/selftests/bpf/prog_tests/dummy_st_ops.c
+++ b/tools/testing/selftests/bpf/prog_tests/dummy_st_ops.c
@@ -1,7 +1,8 @@
 // SPDX-License-Identifier: GPL-2.0
 /* Copyright (C) 2021. Huawei Technologies Co., Ltd */
 #include <test_progs.h>
-#include "dummy_st_ops.skel.h"
+#include "dummy_st_ops_success.skel.h"
+#include "dummy_st_ops_fail.skel.h"
 #include "trace_dummy_st_ops.skel.h"
 
 /* Need to keep consistent with definition in include/linux/bpf.h */
@@ -11,17 +12,17 @@ struct bpf_dummy_ops_state {
 
 static void test_dummy_st_ops_attach(void)
 {
-       struct dummy_st_ops *skel;
+       struct dummy_st_ops_success *skel;
        struct bpf_link *link;
 
-       skel = dummy_st_ops__open_and_load();
+       skel = dummy_st_ops_success__open_and_load();
        if (!ASSERT_OK_PTR(skel, "dummy_st_ops_load"))
                return;
 
        link = bpf_map__attach_struct_ops(skel->maps.dummy_1);
        ASSERT_EQ(libbpf_get_error(link), -EOPNOTSUPP, "dummy_st_ops_attach");
 
-       dummy_st_ops__destroy(skel);
+       dummy_st_ops_success__destroy(skel);
 }
 
 static void test_dummy_init_ret_value(void)
@@ -31,10 +32,10 @@ static void test_dummy_init_ret_value(void)
                .ctx_in = args,
                .ctx_size_in = sizeof(args),
        );
-       struct dummy_st_ops *skel;
+       struct dummy_st_ops_success *skel;
        int fd, err;
 
-       skel = dummy_st_ops__open_and_load();
+       skel = dummy_st_ops_success__open_and_load();
        if (!ASSERT_OK_PTR(skel, "dummy_st_ops_load"))
                return;
 
@@ -43,7 +44,7 @@ static void test_dummy_init_ret_value(void)
        ASSERT_OK(err, "test_run");
        ASSERT_EQ(attr.retval, 0xf2f3f4f5, "test_ret");
 
-       dummy_st_ops__destroy(skel);
+       dummy_st_ops_success__destroy(skel);
 }
 
 static void test_dummy_init_ptr_arg(void)
@@ -58,10 +59,10 @@ static void test_dummy_init_ptr_arg(void)
                .ctx_size_in = sizeof(args),
        );
        struct trace_dummy_st_ops *trace_skel;
-       struct dummy_st_ops *skel;
+       struct dummy_st_ops_success *skel;
        int fd, err;
 
-       skel = dummy_st_ops__open_and_load();
+       skel = dummy_st_ops_success__open_and_load();
        if (!ASSERT_OK_PTR(skel, "dummy_st_ops_load"))
                return;
 
@@ -91,7 +92,7 @@ static void test_dummy_init_ptr_arg(void)
        ASSERT_EQ(trace_skel->bss->val, exp_retval, "fentry_val");
 
 done:
-       dummy_st_ops__destroy(skel);
+       dummy_st_ops_success__destroy(skel);
        trace_dummy_st_ops__destroy(trace_skel);
 }
 
@@ -102,12 +103,12 @@ static void test_dummy_multiple_args(void)
                .ctx_in = args,
                .ctx_size_in = sizeof(args),
        );
-       struct dummy_st_ops *skel;
+       struct dummy_st_ops_success *skel;
        int fd, err;
        size_t i;
        char name[8];
 
-       skel = dummy_st_ops__open_and_load();
+       skel = dummy_st_ops_success__open_and_load();
        if (!ASSERT_OK_PTR(skel, "dummy_st_ops_load"))
                return;
 
@@ -119,7 +120,28 @@ static void test_dummy_multiple_args(void)
                ASSERT_EQ(skel->bss->test_2_args[i], args[i], name);
        }
 
-       dummy_st_ops__destroy(skel);
+       dummy_st_ops_success__destroy(skel);
+}
+
+static void test_dummy_sleepable(void)
+{
+       __u64 args[1] = {0};
+       LIBBPF_OPTS(bpf_test_run_opts, attr,
+               .ctx_in = args,
+               .ctx_size_in = sizeof(args),
+       );
+       struct dummy_st_ops_success *skel;
+       int fd, err;
+
+       skel = dummy_st_ops_success__open_and_load();
+       if (!ASSERT_OK_PTR(skel, "dummy_st_ops_load"))
+               return;
+
+       fd = bpf_program__fd(skel->progs.test_sleepable);
+       err = bpf_prog_test_run_opts(fd, &attr);
+       ASSERT_OK(err, "test_run");
+
+       dummy_st_ops_success__destroy(skel);
 }
 
 void test_dummy_st_ops(void)
@@ -132,4 +154,8 @@ void test_dummy_st_ops(void)
                test_dummy_init_ptr_arg();
        if (test__start_subtest("dummy_multiple_args"))
                test_dummy_multiple_args();
+       if (test__start_subtest("dummy_sleepable"))
+               test_dummy_sleepable();
+
+       RUN_TESTS(dummy_st_ops_fail);
 }

diff --git a/tools/testing/selftests/bpf/progs/dummy_st_ops_fail.c b/tools/testing/selftests/bpf/progs/dummy_st_ops_fail.c
new file mode 100644 (file)
index 0000000..0bf969a
--- /dev/null
+++ b/tools/testing/selftests/bpf/progs/dummy_st_ops_fail.c
@@ -0,0 +1,27 @@
+// 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_misc.h"
+
+char _license[] SEC("license") = "GPL";
+
+SEC("struct_ops.s/test_2")
+__failure __msg("attach to unsupported member test_2 of struct bpf_dummy_ops")
+int BPF_PROG(test_unsupported_field_sleepable,
+            struct bpf_dummy_ops_state *state, int a1, unsigned short a2,
+            char a3, unsigned long a4)
+{
+       /* Tries to mark an unsleepable field in struct bpf_dummy_ops as sleepable. */
+       return 0;
+}
+
+SEC(".struct_ops")
+struct bpf_dummy_ops dummy_1 = {
+       .test_1 = NULL,
+       .test_2 = (void *)test_unsupported_field_sleepable,
+       .test_sleepable = (void *)NULL,
+};

diff --git a/tools/testing/selftests/bpf/progs/dummy_st_ops.c b/tools/testing/selftests/bpf/progs/dummy_st_ops_success.c
similarity index 72%
rename from tools/testing/selftests/bpf/progs/dummy_st_ops.c
rename to tools/testing/selftests/bpf/progs/dummy_st_ops_success.c
index ead87ed..1efa746 100644 (file)
--- a/tools/testing/selftests/bpf/progs/dummy_st_ops.c
+++ b/tools/testing/selftests/bpf/progs/dummy_st_ops_success.c
@@ -1,19 +1,9 @@
 // SPDX-License-Identifier: GPL-2.0
 /* Copyright (C) 2021. Huawei Technologies Co., Ltd */
-#include <linux/bpf.h>
+#include "vmlinux.h"
 #include <bpf/bpf_helpers.h>
 #include <bpf/bpf_tracing.h>
 
-struct bpf_dummy_ops_state {
-       int val;
-} __attribute__((preserve_access_index));
-
-struct bpf_dummy_ops {
-       int (*test_1)(struct bpf_dummy_ops_state *state);
-       int (*test_2)(struct bpf_dummy_ops_state *state, int a1, unsigned short a2,
-                     char a3, unsigned long a4);
-};
-
 char _license[] SEC("license") = "GPL";
 
 SEC("struct_ops/test_1")
@@ -43,8 +33,15 @@ int BPF_PROG(test_2, struct bpf_dummy_ops_state *state, int a1, unsigned short a
        return 0;
 }
 
+SEC("struct_ops.s/test_sleepable")
+int BPF_PROG(test_sleepable, struct bpf_dummy_ops_state *state)
+{
+       return 0;
+}
+
 SEC(".struct_ops")
 struct bpf_dummy_ops dummy_1 = {
        .test_1 = (void *)test_1,
        .test_2 = (void *)test_2,
+       .test_sleepable = (void *)test_sleepable,
 };