[PATCH bpf-next 1/5] bpf: add dummy BPF STRUCT_OPS for test purpose
From: Hou Tao <hidden>
Date: 2021-09-28 02:38:34
Also in:
bpf
Subsystem:
bpf [core], bpf [general] (safe dynamic programs and tools), networking [general], the rest · Maintainers:
Alexei Starovoitov, Daniel Borkmann, Andrii Nakryiko, Eduard Zingerman, Kumar Kartikeya Dwivedi, "David S. Miller", Eric Dumazet, Jakub Kicinski, Paolo Abeni, Linus Torvalds
Currently the test of BPF STRUCT_OPS depends on the specific bpf implementation of tcp_congestion_ops, but it can not cover all basic functionalities (e.g, return value handling), so introduce a dummy BPF STRUCT_OPS for test purpose. Loading a bpf_dummy_ops implementation from userspace is prohibited, and its only purpose is to run BPF_PROG_TYPE_STRUCT_OPS program through bpf(BPF_PROG_TEST_RUN). Signed-off-by: Hou Tao <redacted> --- include/linux/bpf_dummy_ops.h | 14 ++++++++++ kernel/bpf/bpf_struct_ops_types.h | 2 ++ net/bpf/Makefile | 3 +++ net/bpf/bpf_dummy_struct_ops.c | 44 +++++++++++++++++++++++++++++++ 4 files changed, 63 insertions(+) create mode 100644 include/linux/bpf_dummy_ops.h create mode 100644 net/bpf/bpf_dummy_struct_ops.c
diff --git a/include/linux/bpf_dummy_ops.h b/include/linux/bpf_dummy_ops.h
new file mode 100644
index 000000000000..a594ae830eba
--- /dev/null
+++ b/include/linux/bpf_dummy_ops.h@@ -0,0 +1,14 @@ +/* SPDX-License-Identifier: GPL-2.0-only */ +/* + * Copyright (C) 2021. Huawei Technologies Co., Ltd + */ +#ifndef _BPF_DUMMY_OPS_H +#define _BPF_DUMMY_OPS_H + +typedef int (*bpf_dummy_ops_init_t)(void); + +struct bpf_dummy_ops { + bpf_dummy_ops_init_t init; +}; + +#endif
diff --git a/kernel/bpf/bpf_struct_ops_types.h b/kernel/bpf/bpf_struct_ops_types.h
index 066d83ea1c99..02c86cf9c207 100644
--- a/kernel/bpf/bpf_struct_ops_types.h
+++ b/kernel/bpf/bpf_struct_ops_types.h@@ -2,6 +2,8 @@ /* internal file - do not include directly */ #ifdef CONFIG_BPF_JIT +#include <linux/bpf_dummy_ops.h> +BPF_STRUCT_OPS_TYPE(bpf_dummy_ops) #ifdef CONFIG_INET #include <net/tcp.h> BPF_STRUCT_OPS_TYPE(tcp_congestion_ops)
diff --git a/net/bpf/Makefile b/net/bpf/Makefile
index 1c0a98d8c28f..1ebe270bde23 100644
--- a/net/bpf/Makefile
+++ b/net/bpf/Makefile@@ -1,2 +1,5 @@ # SPDX-License-Identifier: GPL-2.0-only obj-$(CONFIG_BPF_SYSCALL) := test_run.o +ifeq ($(CONFIG_BPF_JIT),y) +obj-$(CONFIG_BPF_SYSCALL) += bpf_dummy_struct_ops.o +endif
diff --git a/net/bpf/bpf_dummy_struct_ops.c b/net/bpf/bpf_dummy_struct_ops.c
new file mode 100644
index 000000000000..1249e4bb4ccb
--- /dev/null
+++ b/net/bpf/bpf_dummy_struct_ops.c@@ -0,0 +1,44 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Copyright (C) 2021. Huawei Technologies Co., Ltd + */ +#include <linux/kernel.h> +#include <linux/bpf_verifier.h> +#include <linux/bpf.h> +#include <linux/btf.h> +#include <linux/bpf_dummy_ops.h> + +extern struct bpf_struct_ops bpf_bpf_dummy_ops; + +static int bpf_dummy_init(struct btf *btf) +{ + return 0; +} + +static const struct bpf_verifier_ops bpf_dummy_verifier_ops = { +}; + +static int bpf_dummy_init_member(const struct btf_type *t, + const struct btf_member *member, + void *kdata, const void *udata) +{ + return -EOPNOTSUPP; +} + +static int bpf_dummy_reg(void *kdata) +{ + return -EOPNOTSUPP; +} + +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, + .init_member = bpf_dummy_init_member, + .reg = bpf_dummy_reg, + .unreg = bpf_dummy_unreg, + .name = "bpf_dummy_ops", +};
--
2.29.2