bpf: pass a pointer to a cgroup storage using pcpu variable

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 <guro@fb.com>
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Martin KaFai Lau <kafai@fb.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
This commit is contained in:
Roman Gushchin 2018-08-02 14:27:19 -07:00 committed by Daniel Borkmann
parent de9cbbaadb
commit aa0ad5b039
2 changed files with 17 additions and 0 deletions

View File

@ -4,6 +4,7 @@
#include <linux/errno.h>
#include <linux/jump_label.h>
#include <linux/percpu.h>
#include <linux/rbtree.h>
#include <uapi/linux/bpf.h>
@ -21,6 +22,8 @@ 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 {
@ -97,6 +100,17 @@ 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 = READ_ONCE(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,
@ -250,6 +264,7 @@ 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,

View File

@ -7,6 +7,8 @@
#include <linux/rbtree.h>
#include <linux/slab.h>
DEFINE_PER_CPU(void*, bpf_cgroup_storage);
#ifdef CONFIG_CGROUP_BPF
#define LOCAL_STORAGE_CREATE_FLAG_MASK \