1 files changed, 371 insertions, 0 deletions

diff --git a/net/sched/act_police.c b/net/sched/act_police.c
new file mode 100644
index 000000000..4db25959e
--- /dev/null
+++ b/net/sched/act_police.c
@@ -0,0 +1,371 @@
+/*
+ * net/sched/act_police.c	Input police filter
+ *
+ *		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:	Alexey Kuznetsov, <kuznet@ms2.inr.ac.ru>
+ * 		J Hadi Salim (action changes)
+ */
+
+#include <linux/module.h>
+#include <linux/types.h>
+#include <linux/kernel.h>
+#include <linux/string.h>
+#include <linux/errno.h>
+#include <linux/skbuff.h>
+#include <linux/rtnetlink.h>
+#include <linux/init.h>
+#include <linux/slab.h>
+#include <net/act_api.h>
+#include <net/netlink.h>
+
+struct tcf_police {
+	struct tc_action	common;
+	int			tcfp_result;
+	u32			tcfp_ewma_rate;
+	s64			tcfp_burst;
+	u32			tcfp_mtu;
+	s64			tcfp_toks;
+	s64			tcfp_ptoks;
+	s64			tcfp_mtu_ptoks;
+	s64			tcfp_t_c;
+	struct psched_ratecfg	rate;
+	bool			rate_present;
+	struct psched_ratecfg	peak;
+	bool			peak_present;
+};
+
+#define to_police(pc) ((struct tcf_police *)pc)
+
+/* old policer structure from before tc actions */
+struct tc_police_compat {
+	u32			index;
+	int			action;
+	u32			limit;
+	u32			burst;
+	u32			mtu;
+	struct tc_ratespec	rate;
+	struct tc_ratespec	peakrate;
+};
+
+/* Each policer is serialized by its individual spinlock */
+
+static unsigned int police_net_id;
+static struct tc_action_ops act_police_ops;
+
+static int tcf_police_walker(struct net *net, struct sk_buff *skb,
+				 struct netlink_callback *cb, int type,
+				 const struct tc_action_ops *ops,
+				 struct netlink_ext_ack *extack)
+{
+	struct tc_action_net *tn = net_generic(net, police_net_id);
+
+	return tcf_generic_walker(tn, skb, cb, type, ops, extack);
+}
+
+static const struct nla_policy police_policy[TCA_POLICE_MAX + 1] = {
+	[TCA_POLICE_RATE]	= { .len = TC_RTAB_SIZE },
+	[TCA_POLICE_PEAKRATE]	= { .len = TC_RTAB_SIZE },
+	[TCA_POLICE_AVRATE]	= { .type = NLA_U32 },
+	[TCA_POLICE_RESULT]	= { .type = NLA_U32 },
+};
+
+static int tcf_police_init(struct net *net, struct nlattr *nla,
+			       struct nlattr *est, struct tc_action **a,
+			       int ovr, int bind, bool rtnl_held,
+			       struct netlink_ext_ack *extack)
+{
+	int ret = 0, err;
+	struct nlattr *tb[TCA_POLICE_MAX + 1];
+	struct tc_police *parm;
+	struct tcf_police *police;
+	struct qdisc_rate_table *R_tab = NULL, *P_tab = NULL;
+	struct tc_action_net *tn = net_generic(net, police_net_id);
+	bool exists = false;
+	u32 index;
+	int size;
+
+	if (nla == NULL)
+		return -EINVAL;
+
+	err = nla_parse_nested(tb, TCA_POLICE_MAX, nla, police_policy, NULL);
+	if (err < 0)
+		return err;
+
+	if (tb[TCA_POLICE_TBF] == NULL)
+		return -EINVAL;
+	size = nla_len(tb[TCA_POLICE_TBF]);
+	if (size != sizeof(*parm) && size != sizeof(struct tc_police_compat))
+		return -EINVAL;
+
+	parm = nla_data(tb[TCA_POLICE_TBF]);
+	index = parm->index;
+	err = tcf_idr_check_alloc(tn, &index, a, bind);
+	if (err < 0)
+		return err;
+	exists = err;
+	if (exists && bind)
+		return 0;
+
+	if (!exists) {
+		ret = tcf_idr_create(tn, index, NULL, a,
+				     &act_police_ops, bind, false);
+		if (ret) {
+			tcf_idr_cleanup(tn, index);
+			return ret;
+		}
+		ret = ACT_P_CREATED;
+	} else if (!ovr) {
+		tcf_idr_release(*a, bind);
+		return -EEXIST;
+	}
+
+	police = to_police(*a);
+	if (parm->rate.rate) {
+		err = -ENOMEM;
+		R_tab = qdisc_get_rtab(&parm->rate, tb[TCA_POLICE_RATE], NULL);
+		if (R_tab == NULL)
+			goto failure;
+
+		if (parm->peakrate.rate) {
+			P_tab = qdisc_get_rtab(&parm->peakrate,
+					       tb[TCA_POLICE_PEAKRATE], NULL);
+			if (P_tab == NULL)
+				goto failure;
+		}
+	}
+
+	if (est) {
+		err = gen_replace_estimator(&police->tcf_bstats, NULL,
+					    &police->tcf_rate_est,
+					    &police->tcf_lock,
+					    NULL, est);
+		if (err)
+			goto failure;
+	} else if (tb[TCA_POLICE_AVRATE] &&
+		   (ret == ACT_P_CREATED ||
+		    !gen_estimator_active(&police->tcf_rate_est))) {
+		err = -EINVAL;
+		goto failure;
+	}
+
+	spin_lock_bh(&police->tcf_lock);
+	/* No failure allowed after this point */
+	police->tcfp_mtu = parm->mtu;
+	if (police->tcfp_mtu == 0) {
+		police->tcfp_mtu = ~0;
+		if (R_tab)
+			police->tcfp_mtu = 255 << R_tab->rate.cell_log;
+	}
+	if (R_tab) {
+		police->rate_present = true;
+		psched_ratecfg_precompute(&police->rate, &R_tab->rate, 0);
+		qdisc_put_rtab(R_tab);
+	} else {
+		police->rate_present = false;
+	}
+	if (P_tab) {
+		police->peak_present = true;
+		psched_ratecfg_precompute(&police->peak, &P_tab->rate, 0);
+		qdisc_put_rtab(P_tab);
+	} else {
+		police->peak_present = false;
+	}
+
+	if (tb[TCA_POLICE_RESULT])
+		police->tcfp_result = nla_get_u32(tb[TCA_POLICE_RESULT]);
+	police->tcfp_burst = PSCHED_TICKS2NS(parm->burst);
+	police->tcfp_toks = police->tcfp_burst;
+	if (police->peak_present) {
+		police->tcfp_mtu_ptoks = (s64) psched_l2t_ns(&police->peak,
+							     police->tcfp_mtu);
+		police->tcfp_ptoks = police->tcfp_mtu_ptoks;
+	}
+	police->tcf_action = parm->action;
+
+	if (tb[TCA_POLICE_AVRATE])
+		police->tcfp_ewma_rate = nla_get_u32(tb[TCA_POLICE_AVRATE]);
+
+	spin_unlock_bh(&police->tcf_lock);
+	if (ret != ACT_P_CREATED)
+		return ret;
+
+	police->tcfp_t_c = ktime_get_ns();
+	tcf_idr_insert(tn, *a);
+
+	return ret;
+
+failure:
+	qdisc_put_rtab(P_tab);
+	qdisc_put_rtab(R_tab);
+	tcf_idr_release(*a, bind);
+	return err;
+}
+
+static int tcf_police_act(struct sk_buff *skb, const struct tc_action *a,
+			  struct tcf_result *res)
+{
+	struct tcf_police *police = to_police(a);
+	s64 now;
+	s64 toks;
+	s64 ptoks = 0;
+
+	spin_lock(&police->tcf_lock);
+
+	bstats_update(&police->tcf_bstats, skb);
+	tcf_lastuse_update(&police->tcf_tm);
+
+	if (police->tcfp_ewma_rate) {
+		struct gnet_stats_rate_est64 sample;
+
+		if (!gen_estimator_read(&police->tcf_rate_est, &sample) ||
+		    sample.bps >= police->tcfp_ewma_rate) {
+			police->tcf_qstats.overlimits++;
+			if (police->tcf_action == TC_ACT_SHOT)
+				police->tcf_qstats.drops++;
+			spin_unlock(&police->tcf_lock);
+			return police->tcf_action;
+		}
+	}
+
+	if (qdisc_pkt_len(skb) <= police->tcfp_mtu) {
+		if (!police->rate_present) {
+			spin_unlock(&police->tcf_lock);
+			return police->tcfp_result;
+		}
+
+		now = ktime_get_ns();
+		toks = min_t(s64, now - police->tcfp_t_c,
+			     police->tcfp_burst);
+		if (police->peak_present) {
+			ptoks = toks + police->tcfp_ptoks;
+			if (ptoks > police->tcfp_mtu_ptoks)
+				ptoks = police->tcfp_mtu_ptoks;
+			ptoks -= (s64) psched_l2t_ns(&police->peak,
+						     qdisc_pkt_len(skb));
+		}
+		toks += police->tcfp_toks;
+		if (toks > police->tcfp_burst)
+			toks = police->tcfp_burst;
+		toks -= (s64) psched_l2t_ns(&police->rate, qdisc_pkt_len(skb));
+		if ((toks|ptoks) >= 0) {
+			police->tcfp_t_c = now;
+			police->tcfp_toks = toks;
+			police->tcfp_ptoks = ptoks;
+			if (police->tcfp_result == TC_ACT_SHOT)
+				police->tcf_qstats.drops++;
+			spin_unlock(&police->tcf_lock);
+			return police->tcfp_result;
+		}
+	}
+
+	police->tcf_qstats.overlimits++;
+	if (police->tcf_action == TC_ACT_SHOT)
+		police->tcf_qstats.drops++;
+	spin_unlock(&police->tcf_lock);
+	return police->tcf_action;
+}
+
+static int tcf_police_dump(struct sk_buff *skb, struct tc_action *a,
+			       int bind, int ref)
+{
+	unsigned char *b = skb_tail_pointer(skb);
+	struct tcf_police *police = to_police(a);
+	struct tc_police opt = {
+		.index = police->tcf_index,
+		.refcnt = refcount_read(&police->tcf_refcnt) - ref,
+		.bindcnt = atomic_read(&police->tcf_bindcnt) - bind,
+	};
+	struct tcf_t t;
+
+	spin_lock_bh(&police->tcf_lock);
+	opt.action = police->tcf_action;
+	opt.mtu = police->tcfp_mtu;
+	opt.burst = PSCHED_NS2TICKS(police->tcfp_burst);
+	if (police->rate_present)
+		psched_ratecfg_getrate(&opt.rate, &police->rate);
+	if (police->peak_present)
+		psched_ratecfg_getrate(&opt.peakrate, &police->peak);
+	if (nla_put(skb, TCA_POLICE_TBF, sizeof(opt), &opt))
+		goto nla_put_failure;
+	if (police->tcfp_result &&
+	    nla_put_u32(skb, TCA_POLICE_RESULT, police->tcfp_result))
+		goto nla_put_failure;
+	if (police->tcfp_ewma_rate &&
+	    nla_put_u32(skb, TCA_POLICE_AVRATE, police->tcfp_ewma_rate))
+		goto nla_put_failure;
+
+	t.install = jiffies_to_clock_t(jiffies - police->tcf_tm.install);
+	t.lastuse = jiffies_to_clock_t(jiffies - police->tcf_tm.lastuse);
+	t.firstuse = jiffies_to_clock_t(jiffies - police->tcf_tm.firstuse);
+	t.expires = jiffies_to_clock_t(police->tcf_tm.expires);
+	if (nla_put_64bit(skb, TCA_POLICE_TM, sizeof(t), &t, TCA_POLICE_PAD))
+		goto nla_put_failure;
+	spin_unlock_bh(&police->tcf_lock);
+
+	return skb->len;
+
+nla_put_failure:
+	spin_unlock_bh(&police->tcf_lock);
+	nlmsg_trim(skb, b);
+	return -1;
+}
+
+static int tcf_police_search(struct net *net, struct tc_action **a, u32 index,
+			     struct netlink_ext_ack *extack)
+{
+	struct tc_action_net *tn = net_generic(net, police_net_id);
+
+	return tcf_idr_search(tn, a, index);
+}
+
+MODULE_AUTHOR("Alexey Kuznetsov");
+MODULE_DESCRIPTION("Policing actions");
+MODULE_LICENSE("GPL");
+
+static struct tc_action_ops act_police_ops = {
+	.kind		=	"police",
+	.type		=	TCA_ID_POLICE,
+	.owner		=	THIS_MODULE,
+	.act		=	tcf_police_act,
+	.dump		=	tcf_police_dump,
+	.init		=	tcf_police_init,
+	.walk		=	tcf_police_walker,
+	.lookup		=	tcf_police_search,
+	.size		=	sizeof(struct tcf_police),
+};
+
+static __net_init int police_init_net(struct net *net)
+{
+	struct tc_action_net *tn = net_generic(net, police_net_id);
+
+	return tc_action_net_init(net, tn, &act_police_ops);
+}
+
+static void __net_exit police_exit_net(struct list_head *net_list)
+{
+	tc_action_net_exit(net_list, police_net_id);
+}
+
+static struct pernet_operations police_net_ops = {
+	.init = police_init_net,
+	.exit_batch = police_exit_net,
+	.id   = &police_net_id,
+	.size = sizeof(struct tc_action_net),
+};
+
+static int __init police_init_module(void)
+{
+	return tcf_register_action(&act_police_ops, &police_net_ops);
+}
+
+static void __exit police_cleanup_module(void)
+{
+	tcf_unregister_action(&act_police_ops, &police_net_ops);
+}
+
+module_init(police_init_module);
+module_exit(police_cleanup_module);