alistair23-linux/include/net/cls_cgroup.h
Thomas Gleixner 2874c5fd28 treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 152
Based on 1 normalized pattern(s):

  this program is free software you can redistribute it and or modify
  it under the terms of the gnu general public license as published by
  the free software foundation either version 2 of the license or at
  your option any later version

extracted by the scancode license scanner the SPDX license identifier

  GPL-2.0-or-later

has been chosen to replace the boilerplate/reference in 3029 file(s).

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Allison Randal <allison@lohutok.net>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190527070032.746973796@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-05-30 11:26:32 -07:00

84 lines
1.9 KiB
C

/* SPDX-License-Identifier: GPL-2.0-or-later */
/*
* cls_cgroup.h Control Group Classifier
*
* Authors: Thomas Graf <tgraf@suug.ch>
*/
#ifndef _NET_CLS_CGROUP_H
#define _NET_CLS_CGROUP_H
#include <linux/cgroup.h>
#include <linux/hardirq.h>
#include <linux/rcupdate.h>
#include <net/sock.h>
#include <net/inet_sock.h>
#ifdef CONFIG_CGROUP_NET_CLASSID
struct cgroup_cls_state {
struct cgroup_subsys_state css;
u32 classid;
};
struct cgroup_cls_state *task_cls_state(struct task_struct *p);
static inline u32 task_cls_classid(struct task_struct *p)
{
u32 classid;
if (in_interrupt())
return 0;
rcu_read_lock();
classid = container_of(task_css(p, net_cls_cgrp_id),
struct cgroup_cls_state, css)->classid;
rcu_read_unlock();
return classid;
}
static inline void sock_update_classid(struct sock_cgroup_data *skcd)
{
u32 classid;
classid = task_cls_classid(current);
sock_cgroup_set_classid(skcd, classid);
}
static inline u32 task_get_classid(const struct sk_buff *skb)
{
u32 classid = task_cls_state(current)->classid;
/* Due to the nature of the classifier it is required to ignore all
* packets originating from softirq context as accessing `current'
* would lead to false results.
*
* This test assumes that all callers of dev_queue_xmit() explicitly
* disable bh. Knowing this, it is possible to detect softirq based
* calls by looking at the number of nested bh disable calls because
* softirqs always disables bh.
*/
if (in_serving_softirq()) {
struct sock *sk = skb_to_full_sk(skb);
/* If there is an sock_cgroup_classid we'll use that. */
if (!sk || !sk_fullsock(sk))
return 0;
classid = sock_cgroup_classid(&sk->sk_cgrp_data);
}
return classid;
}
#else /* !CONFIG_CGROUP_NET_CLASSID */
static inline void sock_update_classid(struct sock_cgroup_data *skcd)
{
}
static inline u32 task_get_classid(const struct sk_buff *skb)
{
return 0;
}
#endif /* CONFIG_CGROUP_NET_CLASSID */
#endif /* _NET_CLS_CGROUP_H */