v4.19.13 snapshot.
diff --git a/include/net/cls_cgroup.h b/include/net/cls_cgroup.h
new file mode 100644
index 0000000..74c9693
--- /dev/null
+++ b/include/net/cls_cgroup.h
@@ -0,0 +1,88 @@
+/*
+ * cls_cgroup.h Control Group Classifier
+ *
+ * Authors: Thomas Graf <tgraf@suug.ch>
+ *
+ * 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.
+ *
+ */
+
+#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 */