1 files changed, 111 insertions, 0 deletions
diff --git a/net/core/netclassid_cgroup.c b/net/core/netclassid_cgroup.c
new file mode 100644
index 00000000000..30d903b19c6
--- /dev/null
+++ b/net/core/netclassid_cgroup.c
@@ -0,0 +1,111 @@
+/*
+ * net/core/netclassid_cgroup.c	Classid Cgroupfs Handling
+ *
+ *		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.
+ *
+ * Authors:	Thomas Graf <tgraf@suug.ch>
+ */
+
+#include <linux/module.h>
+#include <linux/slab.h>
+#include <linux/cgroup.h>
+#include <linux/fdtable.h>
+#include <net/cls_cgroup.h>
+#include <net/sock.h>
+
+static inline struct cgroup_cls_state *css_cls_state(struct cgroup_subsys_state *css)
+{
+	return css ? container_of(css, struct cgroup_cls_state, css) : NULL;
+}
+
+struct cgroup_cls_state *task_cls_state(struct task_struct *p)
+{
+	return css_cls_state(task_css(p, net_cls_cgrp_id));
+}
+EXPORT_SYMBOL_GPL(task_cls_state);
+
+static struct cgroup_subsys_state *
+cgrp_css_alloc(struct cgroup_subsys_state *parent_css)
+{
+	struct cgroup_cls_state *cs;
+
+	cs = kzalloc(sizeof(*cs), GFP_KERNEL);
+	if (!cs)
+		return ERR_PTR(-ENOMEM);
+
+	return &cs->css;
+}
+
+static int cgrp_css_online(struct cgroup_subsys_state *css)
+{
+	struct cgroup_cls_state *cs = css_cls_state(css);
+	struct cgroup_cls_state *parent = css_cls_state(css->parent);
+
+	if (parent)
+		cs->classid = parent->classid;
+
+	return 0;
+}
+
+static void cgrp_css_free(struct cgroup_subsys_state *css)
+{
+	kfree(css_cls_state(css));
+}
+
+static int update_classid(const void *v, struct file *file, unsigned n)
+{
+	int err;
+	struct socket *sock = sock_from_file(file, &err);
+
+	if (sock)
+		sock->sk->sk_classid = (u32)(unsigned long)v;
+
+	return 0;
+}
+
+static void cgrp_attach(struct cgroup_subsys_state *css,
+			struct cgroup_taskset *tset)
+{
+	struct cgroup_cls_state *cs = css_cls_state(css);
+	void *v = (void *)(unsigned long)cs->classid;
+	struct task_struct *p;
+
+	cgroup_taskset_for_each(p, tset) {
+		task_lock(p);
+		iterate_fd(p->files, 0, update_classid, v);
+		task_unlock(p);
+	}
+}
+
+static u64 read_classid(struct cgroup_subsys_state *css, struct cftype *cft)
+{
+	return css_cls_state(css)->classid;
+}
+
+static int write_classid(struct cgroup_subsys_state *css, struct cftype *cft,
+			 u64 value)
+{
+	css_cls_state(css)->classid = (u32) value;
+
+	return 0;
+}
+
+static struct cftype ss_files[] = {
+	{
+		.name		= "classid",
+		.read_u64	= read_classid,
+		.write_u64	= write_classid,
+	},
+	{ }	/* terminate */
+};
+
+struct cgroup_subsys net_cls_cgrp_subsys = {
+	.css_alloc		= cgrp_css_alloc,
+	.css_online		= cgrp_css_online,
+	.css_free		= cgrp_css_free,
+	.attach			= cgrp_attach,
+	.base_cftypes		= ss_files,
+};