2 * net/core/netclassid_cgroup.c Classid Cgroupfs Handling
4 * This program is free software; you can redistribute it and/or
5 * modify it under the terms of the GNU General Public License
6 * as published by the Free Software Foundation; either version
7 * 2 of the License, or (at your option) any later version.
9 * Authors: Thomas Graf <tgraf@suug.ch>
12 #include <linux/module.h>
13 #include <linux/slab.h>
14 #include <linux/cgroup.h>
15 #include <linux/fdtable.h>
16 #include <net/cls_cgroup.h>
19 static inline struct cgroup_cls_state *css_cls_state(struct cgroup_subsys_state *css)
21 return css ? container_of(css, struct cgroup_cls_state, css) : NULL;
24 struct cgroup_cls_state *task_cls_state(struct task_struct *p)
26 return css_cls_state(task_css_check(p, net_cls_cgrp_id,
27 rcu_read_lock_bh_held()));
29 EXPORT_SYMBOL_GPL(task_cls_state);
31 static struct cgroup_subsys_state *
32 cgrp_css_alloc(struct cgroup_subsys_state *parent_css)
34 struct cgroup_cls_state *cs;
36 cs = kzalloc(sizeof(*cs), GFP_KERNEL);
38 return ERR_PTR(-ENOMEM);
43 static int cgrp_css_online(struct cgroup_subsys_state *css)
45 struct cgroup_cls_state *cs = css_cls_state(css);
46 struct cgroup_cls_state *parent = css_cls_state(css->parent);
49 cs->classid = parent->classid;
54 static void cgrp_css_free(struct cgroup_subsys_state *css)
56 kfree(css_cls_state(css));
59 static int update_classid_sock(const void *v, struct file *file, unsigned n)
62 struct socket *sock = sock_from_file(file, &err);
65 spin_lock(&cgroup_sk_update_lock);
66 sock_cgroup_set_classid(&sock->sk->sk_cgrp_data,
68 spin_unlock(&cgroup_sk_update_lock);
73 static void update_classid(struct cgroup_subsys_state *css, void *v)
75 struct css_task_iter it;
76 struct task_struct *p;
78 css_task_iter_start(css, &it);
79 while ((p = css_task_iter_next(&it))) {
81 iterate_fd(p->files, 0, update_classid_sock, v);
84 css_task_iter_end(&it);
87 static void cgrp_attach(struct cgroup_taskset *tset)
89 struct cgroup_subsys_state *css;
91 cgroup_taskset_first(tset, &css);
93 (void *)(unsigned long)css_cls_state(css)->classid);
96 static u64 read_classid(struct cgroup_subsys_state *css, struct cftype *cft)
98 return css_cls_state(css)->classid;
101 static int write_classid(struct cgroup_subsys_state *css, struct cftype *cft,
104 struct cgroup_cls_state *cs = css_cls_state(css);
106 cgroup_sk_alloc_disable();
108 cs->classid = (u32)value;
110 update_classid(css, (void *)(unsigned long)cs->classid);
114 static struct cftype ss_files[] = {
117 .read_u64 = read_classid,
118 .write_u64 = write_classid,
123 struct cgroup_subsys net_cls_cgrp_subsys = {
124 .css_alloc = cgrp_css_alloc,
125 .css_online = cgrp_css_online,
126 .css_free = cgrp_css_free,
127 .attach = cgrp_attach,
128 .legacy_cftypes = ss_files,