Linux 4.6-rc6
[cris-mirror.git] / include / net / cls_cgroup.h
blob74c9693d4941dd0f4a08526968a9783727249fb5
1 /*
2 * cls_cgroup.h Control Group Classifier
4 * Authors: Thomas Graf <tgraf@suug.ch>
6 * This program is free software; you can redistribute it and/or modify it
7 * under the terms of the GNU General Public License as published by the Free
8 * Software Foundation; either version 2 of the License, or (at your option)
9 * any later version.
13 #ifndef _NET_CLS_CGROUP_H
14 #define _NET_CLS_CGROUP_H
16 #include <linux/cgroup.h>
17 #include <linux/hardirq.h>
18 #include <linux/rcupdate.h>
19 #include <net/sock.h>
20 #include <net/inet_sock.h>
22 #ifdef CONFIG_CGROUP_NET_CLASSID
23 struct cgroup_cls_state {
24 struct cgroup_subsys_state css;
25 u32 classid;
28 struct cgroup_cls_state *task_cls_state(struct task_struct *p);
30 static inline u32 task_cls_classid(struct task_struct *p)
32 u32 classid;
34 if (in_interrupt())
35 return 0;
37 rcu_read_lock();
38 classid = container_of(task_css(p, net_cls_cgrp_id),
39 struct cgroup_cls_state, css)->classid;
40 rcu_read_unlock();
42 return classid;
45 static inline void sock_update_classid(struct sock_cgroup_data *skcd)
47 u32 classid;
49 classid = task_cls_classid(current);
50 sock_cgroup_set_classid(skcd, classid);
53 static inline u32 task_get_classid(const struct sk_buff *skb)
55 u32 classid = task_cls_state(current)->classid;
57 /* Due to the nature of the classifier it is required to ignore all
58 * packets originating from softirq context as accessing `current'
59 * would lead to false results.
61 * This test assumes that all callers of dev_queue_xmit() explicitly
62 * disable bh. Knowing this, it is possible to detect softirq based
63 * calls by looking at the number of nested bh disable calls because
64 * softirqs always disables bh.
66 if (in_serving_softirq()) {
67 struct sock *sk = skb_to_full_sk(skb);
69 /* If there is an sock_cgroup_classid we'll use that. */
70 if (!sk || !sk_fullsock(sk))
71 return 0;
73 classid = sock_cgroup_classid(&sk->sk_cgrp_data);
76 return classid;
78 #else /* !CONFIG_CGROUP_NET_CLASSID */
79 static inline void sock_update_classid(struct sock_cgroup_data *skcd)
83 static inline u32 task_get_classid(const struct sk_buff *skb)
85 return 0;
87 #endif /* CONFIG_CGROUP_NET_CLASSID */
88 #endif /* _NET_CLS_CGROUP_H */