[PATCH v2 bpf-next 03/14] bpf: pass a pointer to a cgroup storage using pcpu variable
From: Roman Gushchin <hidden>
Date: 2018-07-05 20:57:05
Also in:
lkml
Subsystem:
bpf [core], bpf [general] (safe dynamic programs and tools), bpf [storage & cgroups], the rest · Maintainers:
Alexei Starovoitov, Daniel Borkmann, Andrii Nakryiko, Eduard Zingerman, Kumar Kartikeya Dwivedi, Martin KaFai Lau, Linus Torvalds
This commit introduces the bpf_cgroup_storage_set() helper, which will be used to pass a pointer to a cgroup storage to the bpf helper. Signed-off-by: Roman Gushchin <redacted> Cc: Alexei Starovoitov <ast@kernel.org> Cc: Daniel Borkmann <daniel@iogearbox.net> Acked-by: Martin KaFai Lau <redacted> --- include/linux/bpf-cgroup.h | 15 +++++++++++++++ kernel/bpf/local_storage.c | 2 ++ 2 files changed, 17 insertions(+)
diff --git a/include/linux/bpf-cgroup.h b/include/linux/bpf-cgroup.h
index 6b0e7bd4b154..ce77a6dffb6d 100644
--- a/include/linux/bpf-cgroup.h
+++ b/include/linux/bpf-cgroup.h@@ -3,6 +3,7 @@ #define _BPF_CGROUP_H #include <linux/jump_label.h> +#include <linux/percpu-defs.h> #include <linux/rbtree.h> #include <uapi/linux/bpf.h>
@@ -20,6 +21,8 @@ struct bpf_cgroup_storage; extern struct static_key_false cgroup_bpf_enabled_key; #define cgroup_bpf_enabled static_branch_unlikely(&cgroup_bpf_enabled_key) +DECLARE_PER_CPU(void*, bpf_cgroup_storage); + struct bpf_cgroup_storage_map; struct bpf_storage_buffer {
@@ -96,6 +99,17 @@ int __cgroup_bpf_run_filter_sock_ops(struct sock *sk, int __cgroup_bpf_check_dev_permission(short dev_type, u32 major, u32 minor, short access, enum bpf_attach_type type); +static inline void bpf_cgroup_storage_set(struct bpf_cgroup_storage *storage) +{ + struct bpf_storage_buffer *buf; + + if (!storage) + return; + + buf = rcu_dereference(storage->buf); + this_cpu_write(bpf_cgroup_storage, &buf->data[0]); +} + struct bpf_cgroup_storage *bpf_cgroup_storage_alloc(struct bpf_prog *prog); void bpf_cgroup_storage_free(struct bpf_cgroup_storage *storage); void bpf_cgroup_storage_link(struct bpf_cgroup_storage *storage,
@@ -249,6 +263,7 @@ static inline int cgroup_bpf_prog_query(const union bpf_attr *attr, return -EINVAL; } +static inline void bpf_cgroup_storage_set(struct bpf_cgroup_storage *storage) {} static inline int bpf_cgroup_storage_assign(struct bpf_prog *prog, struct bpf_map *map) { return 0; } static inline void bpf_cgroup_storage_release(struct bpf_prog *prog,
diff --git a/kernel/bpf/local_storage.c b/kernel/bpf/local_storage.c
index 940889eda2c7..38810a712971 100644
--- a/kernel/bpf/local_storage.c
+++ b/kernel/bpf/local_storage.c@@ -7,6 +7,8 @@ #include <linux/rbtree.h> #include <linux/slab.h> +DEFINE_PER_CPU(void*, bpf_cgroup_storage); + #ifdef CONFIG_CGROUP_BPF struct bpf_cgroup_storage_map {
--
2.14.4