v4.19.13 snapshot.
diff --git a/net/sched/cls_basic.c b/net/sched/cls_basic.c
new file mode 100644
index 0000000..6a5dce8
--- /dev/null
+++ b/net/sched/cls_basic.c
@@ -0,0 +1,326 @@
+/*
+ * net/sched/cls_basic.c	Basic Packet Classifier.
+ *
+ *		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/types.h>
+#include <linux/kernel.h>
+#include <linux/string.h>
+#include <linux/errno.h>
+#include <linux/rtnetlink.h>
+#include <linux/skbuff.h>
+#include <linux/idr.h>
+#include <net/netlink.h>
+#include <net/act_api.h>
+#include <net/pkt_cls.h>
+
+struct basic_head {
+	struct list_head	flist;
+	struct idr		handle_idr;
+	struct rcu_head		rcu;
+};
+
+struct basic_filter {
+	u32			handle;
+	struct tcf_exts		exts;
+	struct tcf_ematch_tree	ematches;
+	struct tcf_result	res;
+	struct tcf_proto	*tp;
+	struct list_head	link;
+	struct rcu_work		rwork;
+};
+
+static int basic_classify(struct sk_buff *skb, const struct tcf_proto *tp,
+			  struct tcf_result *res)
+{
+	int r;
+	struct basic_head *head = rcu_dereference_bh(tp->root);
+	struct basic_filter *f;
+
+	list_for_each_entry_rcu(f, &head->flist, link) {
+		if (!tcf_em_tree_match(skb, &f->ematches, NULL))
+			continue;
+		*res = f->res;
+		r = tcf_exts_exec(skb, &f->exts, res);
+		if (r < 0)
+			continue;
+		return r;
+	}
+	return -1;
+}
+
+static void *basic_get(struct tcf_proto *tp, u32 handle)
+{
+	struct basic_head *head = rtnl_dereference(tp->root);
+	struct basic_filter *f;
+
+	list_for_each_entry(f, &head->flist, link) {
+		if (f->handle == handle) {
+			return f;
+		}
+	}
+
+	return NULL;
+}
+
+static int basic_init(struct tcf_proto *tp)
+{
+	struct basic_head *head;
+
+	head = kzalloc(sizeof(*head), GFP_KERNEL);
+	if (head == NULL)
+		return -ENOBUFS;
+	INIT_LIST_HEAD(&head->flist);
+	idr_init(&head->handle_idr);
+	rcu_assign_pointer(tp->root, head);
+	return 0;
+}
+
+static void __basic_delete_filter(struct basic_filter *f)
+{
+	tcf_exts_destroy(&f->exts);
+	tcf_em_tree_destroy(&f->ematches);
+	tcf_exts_put_net(&f->exts);
+	kfree(f);
+}
+
+static void basic_delete_filter_work(struct work_struct *work)
+{
+	struct basic_filter *f = container_of(to_rcu_work(work),
+					      struct basic_filter,
+					      rwork);
+	rtnl_lock();
+	__basic_delete_filter(f);
+	rtnl_unlock();
+}
+
+static void basic_destroy(struct tcf_proto *tp, struct netlink_ext_ack *extack)
+{
+	struct basic_head *head = rtnl_dereference(tp->root);
+	struct basic_filter *f, *n;
+
+	list_for_each_entry_safe(f, n, &head->flist, link) {
+		list_del_rcu(&f->link);
+		tcf_unbind_filter(tp, &f->res);
+		idr_remove(&head->handle_idr, f->handle);
+		if (tcf_exts_get_net(&f->exts))
+			tcf_queue_work(&f->rwork, basic_delete_filter_work);
+		else
+			__basic_delete_filter(f);
+	}
+	idr_destroy(&head->handle_idr);
+	kfree_rcu(head, rcu);
+}
+
+static int basic_delete(struct tcf_proto *tp, void *arg, bool *last,
+			struct netlink_ext_ack *extack)
+{
+	struct basic_head *head = rtnl_dereference(tp->root);
+	struct basic_filter *f = arg;
+
+	list_del_rcu(&f->link);
+	tcf_unbind_filter(tp, &f->res);
+	idr_remove(&head->handle_idr, f->handle);
+	tcf_exts_get_net(&f->exts);
+	tcf_queue_work(&f->rwork, basic_delete_filter_work);
+	*last = list_empty(&head->flist);
+	return 0;
+}
+
+static const struct nla_policy basic_policy[TCA_BASIC_MAX + 1] = {
+	[TCA_BASIC_CLASSID]	= { .type = NLA_U32 },
+	[TCA_BASIC_EMATCHES]	= { .type = NLA_NESTED },
+};
+
+static int basic_set_parms(struct net *net, struct tcf_proto *tp,
+			   struct basic_filter *f, unsigned long base,
+			   struct nlattr **tb,
+			   struct nlattr *est, bool ovr,
+			   struct netlink_ext_ack *extack)
+{
+	int err;
+
+	err = tcf_exts_validate(net, tp, tb, est, &f->exts, ovr, extack);
+	if (err < 0)
+		return err;
+
+	err = tcf_em_tree_validate(tp, tb[TCA_BASIC_EMATCHES], &f->ematches);
+	if (err < 0)
+		return err;
+
+	if (tb[TCA_BASIC_CLASSID]) {
+		f->res.classid = nla_get_u32(tb[TCA_BASIC_CLASSID]);
+		tcf_bind_filter(tp, &f->res, base);
+	}
+
+	f->tp = tp;
+	return 0;
+}
+
+static int basic_change(struct net *net, struct sk_buff *in_skb,
+			struct tcf_proto *tp, unsigned long base, u32 handle,
+			struct nlattr **tca, void **arg, bool ovr,
+			struct netlink_ext_ack *extack)
+{
+	int err;
+	struct basic_head *head = rtnl_dereference(tp->root);
+	struct nlattr *tb[TCA_BASIC_MAX + 1];
+	struct basic_filter *fold = (struct basic_filter *) *arg;
+	struct basic_filter *fnew;
+
+	if (tca[TCA_OPTIONS] == NULL)
+		return -EINVAL;
+
+	err = nla_parse_nested(tb, TCA_BASIC_MAX, tca[TCA_OPTIONS],
+			       basic_policy, NULL);
+	if (err < 0)
+		return err;
+
+	if (fold != NULL) {
+		if (handle && fold->handle != handle)
+			return -EINVAL;
+	}
+
+	fnew = kzalloc(sizeof(*fnew), GFP_KERNEL);
+	if (!fnew)
+		return -ENOBUFS;
+
+	err = tcf_exts_init(&fnew->exts, TCA_BASIC_ACT, TCA_BASIC_POLICE);
+	if (err < 0)
+		goto errout;
+
+	if (!handle) {
+		handle = 1;
+		err = idr_alloc_u32(&head->handle_idr, fnew, &handle,
+				    INT_MAX, GFP_KERNEL);
+	} else if (!fold) {
+		err = idr_alloc_u32(&head->handle_idr, fnew, &handle,
+				    handle, GFP_KERNEL);
+	}
+	if (err)
+		goto errout;
+	fnew->handle = handle;
+
+	err = basic_set_parms(net, tp, fnew, base, tb, tca[TCA_RATE], ovr,
+			      extack);
+	if (err < 0) {
+		if (!fold)
+			idr_remove(&head->handle_idr, fnew->handle);
+		goto errout;
+	}
+
+	*arg = fnew;
+
+	if (fold) {
+		idr_replace(&head->handle_idr, fnew, fnew->handle);
+		list_replace_rcu(&fold->link, &fnew->link);
+		tcf_unbind_filter(tp, &fold->res);
+		tcf_exts_get_net(&fold->exts);
+		tcf_queue_work(&fold->rwork, basic_delete_filter_work);
+	} else {
+		list_add_rcu(&fnew->link, &head->flist);
+	}
+
+	return 0;
+errout:
+	tcf_exts_destroy(&fnew->exts);
+	kfree(fnew);
+	return err;
+}
+
+static void basic_walk(struct tcf_proto *tp, struct tcf_walker *arg)
+{
+	struct basic_head *head = rtnl_dereference(tp->root);
+	struct basic_filter *f;
+
+	list_for_each_entry(f, &head->flist, link) {
+		if (arg->count < arg->skip)
+			goto skip;
+
+		if (arg->fn(tp, f, arg) < 0) {
+			arg->stop = 1;
+			break;
+		}
+skip:
+		arg->count++;
+	}
+}
+
+static void basic_bind_class(void *fh, u32 classid, unsigned long cl)
+{
+	struct basic_filter *f = fh;
+
+	if (f && f->res.classid == classid)
+		f->res.class = cl;
+}
+
+static int basic_dump(struct net *net, struct tcf_proto *tp, void *fh,
+		      struct sk_buff *skb, struct tcmsg *t)
+{
+	struct basic_filter *f = fh;
+	struct nlattr *nest;
+
+	if (f == NULL)
+		return skb->len;
+
+	t->tcm_handle = f->handle;
+
+	nest = nla_nest_start(skb, TCA_OPTIONS);
+	if (nest == NULL)
+		goto nla_put_failure;
+
+	if (f->res.classid &&
+	    nla_put_u32(skb, TCA_BASIC_CLASSID, f->res.classid))
+		goto nla_put_failure;
+
+	if (tcf_exts_dump(skb, &f->exts) < 0 ||
+	    tcf_em_tree_dump(skb, &f->ematches, TCA_BASIC_EMATCHES) < 0)
+		goto nla_put_failure;
+
+	nla_nest_end(skb, nest);
+
+	if (tcf_exts_dump_stats(skb, &f->exts) < 0)
+		goto nla_put_failure;
+
+	return skb->len;
+
+nla_put_failure:
+	nla_nest_cancel(skb, nest);
+	return -1;
+}
+
+static struct tcf_proto_ops cls_basic_ops __read_mostly = {
+	.kind		=	"basic",
+	.classify	=	basic_classify,
+	.init		=	basic_init,
+	.destroy	=	basic_destroy,
+	.get		=	basic_get,
+	.change		=	basic_change,
+	.delete		=	basic_delete,
+	.walk		=	basic_walk,
+	.dump		=	basic_dump,
+	.bind_class	=	basic_bind_class,
+	.owner		=	THIS_MODULE,
+};
+
+static int __init init_basic(void)
+{
+	return register_tcf_proto_ops(&cls_basic_ops);
+}
+
+static void __exit exit_basic(void)
+{
+	unregister_tcf_proto_ops(&cls_basic_ops);
+}
+
+module_init(init_basic)
+module_exit(exit_basic)
+MODULE_LICENSE("GPL");