1 files changed, 154 insertions, 45 deletions

diff --git a/net/sched/sch_red.c b/net/sched/sch_red.c
index 9df9942340ea..479c42d11083 100644
--- a/net/sched/sch_red.c
+++ b/net/sched/sch_red.c
@@ -1,11 +1,7 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
 /*
  * net/sched/sch_red.c	Random Early Detection queue.
  *
- *		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>
  *
  * Changes:
@@ -39,15 +35,23 @@
 
 struct red_sched_data {
 	u32			limit;		/* HARD maximal queue length */
+
 	unsigned char		flags;
+	/* Non-flags in tc_red_qopt.flags. */
+	unsigned char		userbits;
+
 	struct timer_list	adapt_timer;
 	struct Qdisc		*sch;
 	struct red_parms	parms;
 	struct red_vars		vars;
 	struct red_stats	stats;
 	struct Qdisc		*qdisc;
+	struct tcf_qevent	qe_early_drop;
+	struct tcf_qevent	qe_mark;
 };
 
+#define TC_RED_SUPPORTED_FLAGS (TC_RED_HISTORIC_FLAGS | TC_RED_NODROP)
+
 static inline int red_use_ecn(struct red_sched_data *q)
 {
 	return q->flags & TC_RED_ECN;
@@ -58,11 +62,18 @@ static inline int red_use_harddrop(struct red_sched_data *q)
 	return q->flags & TC_RED_HARDDROP;
 }
 
+static int red_use_nodrop(struct red_sched_data *q)
+{
+	return q->flags & TC_RED_NODROP;
+}
+
 static int red_enqueue(struct sk_buff *skb, struct Qdisc *sch,
 		       struct sk_buff **to_free)
 {
+	enum skb_drop_reason reason = SKB_DROP_REASON_QDISC_CONGESTED;
 	struct red_sched_data *q = qdisc_priv(sch);
 	struct Qdisc *child = q->qdisc;
+	unsigned int len;
 	int ret;
 
 	q->vars.qavg = red_calc_qavg(&q->parms,
@@ -78,29 +89,50 @@ static int red_enqueue(struct sk_buff *skb, struct Qdisc *sch,
 
 	case RED_PROB_MARK:
 		qdisc_qstats_overlimit(sch);
-		if (!red_use_ecn(q) || !INET_ECN_set_ce(skb)) {
+		if (!red_use_ecn(q)) {
+			q->stats.prob_drop++;
+			goto congestion_drop;
+		}
+
+		if (INET_ECN_set_ce(skb)) {
+			q->stats.prob_mark++;
+			skb = tcf_qevent_handle(&q->qe_mark, sch, skb, to_free, &ret);
+			if (!skb)
+				return NET_XMIT_CN | ret;
+		} else if (!red_use_nodrop(q)) {
 			q->stats.prob_drop++;
 			goto congestion_drop;
 		}
 
-		q->stats.prob_mark++;
+		/* Non-ECT packet in ECN nodrop mode: queue it. */
 		break;
 
 	case RED_HARD_MARK:
+		reason = SKB_DROP_REASON_QDISC_OVERLIMIT;
 		qdisc_qstats_overlimit(sch);
-		if (red_use_harddrop(q) || !red_use_ecn(q) ||
-		    !INET_ECN_set_ce(skb)) {
+		if (red_use_harddrop(q) || !red_use_ecn(q)) {
+			q->stats.forced_drop++;
+			goto congestion_drop;
+		}
+
+		if (INET_ECN_set_ce(skb)) {
+			q->stats.forced_mark++;
+			skb = tcf_qevent_handle(&q->qe_mark, sch, skb, to_free, &ret);
+			if (!skb)
+				return NET_XMIT_CN | ret;
+		} else if (!red_use_nodrop(q)) {
 			q->stats.forced_drop++;
 			goto congestion_drop;
 		}
 
-		q->stats.forced_mark++;
+		/* Non-ECT packet in ECN nodrop mode: queue it. */
 		break;
 	}
 
+	len = qdisc_pkt_len(skb);
 	ret = qdisc_enqueue(skb, child, to_free);
 	if (likely(ret == NET_XMIT_SUCCESS)) {
-		qdisc_qstats_backlog_inc(sch, skb);
+		sch->qstats.backlog += len;
 		sch->q.qlen++;
 	} else if (net_xmit_drop_count(ret)) {
 		q->stats.pdrop++;
@@ -109,7 +141,11 @@ static int red_enqueue(struct sk_buff *skb, struct Qdisc *sch,
 	return ret;
 
 congestion_drop:
-	qdisc_drop(skb, sch, to_free);
+	skb = tcf_qevent_handle(&q->qe_early_drop, sch, skb, to_free, &ret);
+	if (!skb)
+		return NET_XMIT_CN | ret;
+
+	qdisc_drop_reason(skb, sch, to_free, reason);
 	return NET_XMIT_CN;
 }
 
@@ -144,8 +180,6 @@ static void red_reset(struct Qdisc *sch)
 	struct red_sched_data *q = qdisc_priv(sch);
 
 	qdisc_reset(q->qdisc);
-	sch->qstats.backlog = 0;
-	sch->q.qlen = 0;
 	red_restart(&q->vars);
 }
 
@@ -169,6 +203,7 @@ static int red_offload(struct Qdisc *sch, bool enable)
 		opt.set.limit = q->limit;
 		opt.set.is_ecn = red_use_ecn(q);
 		opt.set.is_harddrop = red_use_harddrop(q);
+		opt.set.is_nodrop = red_use_nodrop(q);
 		opt.set.qstats = &sch->qstats;
 	} else {
 		opt.command = TC_RED_DESTROY;
@@ -181,44 +216,54 @@ static void red_destroy(struct Qdisc *sch)
 {
 	struct red_sched_data *q = qdisc_priv(sch);
 
-	del_timer_sync(&q->adapt_timer);
+	tcf_qevent_destroy(&q->qe_mark, sch);
+	tcf_qevent_destroy(&q->qe_early_drop, sch);
+	timer_delete_sync(&q->adapt_timer);
 	red_offload(sch, false);
 	qdisc_put(q->qdisc);
 }
 
 static const struct nla_policy red_policy[TCA_RED_MAX + 1] = {
+	[TCA_RED_UNSPEC] = { .strict_start_type = TCA_RED_FLAGS },
 	[TCA_RED_PARMS]	= { .len = sizeof(struct tc_red_qopt) },
 	[TCA_RED_STAB]	= { .len = RED_STAB_SIZE },
 	[TCA_RED_MAX_P] = { .type = NLA_U32 },
+	[TCA_RED_FLAGS] = NLA_POLICY_BITFIELD32(TC_RED_SUPPORTED_FLAGS),
+	[TCA_RED_EARLY_DROP_BLOCK] = { .type = NLA_U32 },
+	[TCA_RED_MARK_BLOCK] = { .type = NLA_U32 },
 };
 
-static int red_change(struct Qdisc *sch, struct nlattr *opt,
-		      struct netlink_ext_ack *extack)
+static int __red_change(struct Qdisc *sch, struct nlattr **tb,
+			struct netlink_ext_ack *extack)
 {
 	struct Qdisc *old_child = NULL, *child = NULL;
 	struct red_sched_data *q = qdisc_priv(sch);
-	struct nlattr *tb[TCA_RED_MAX + 1];
+	struct nla_bitfield32 flags_bf;
 	struct tc_red_qopt *ctl;
+	unsigned char userbits;
+	unsigned char flags;
 	int err;
 	u32 max_P;
-
-	if (opt == NULL)
-		return -EINVAL;
-
-	err = nla_parse_nested(tb, TCA_RED_MAX, opt, red_policy, NULL);
-	if (err < 0)
-		return err;
+	u8 *stab;
 
 	if (tb[TCA_RED_PARMS] == NULL ||
 	    tb[TCA_RED_STAB] == NULL)
 		return -EINVAL;
 
-	max_P = tb[TCA_RED_MAX_P] ? nla_get_u32(tb[TCA_RED_MAX_P]) : 0;
+	max_P = nla_get_u32_default(tb[TCA_RED_MAX_P], 0);
 
 	ctl = nla_data(tb[TCA_RED_PARMS]);
-	if (!red_check_params(ctl->qth_min, ctl->qth_max, ctl->Wlog))
+	stab = nla_data(tb[TCA_RED_STAB]);
+	if (!red_check_params(ctl->qth_min, ctl->qth_max, ctl->Wlog,
+			      ctl->Scell_log, stab))
 		return -EINVAL;
 
+	err = red_get_flags(ctl->flags, TC_RED_HISTORIC_FLAGS,
+			    tb[TCA_RED_FLAGS], TC_RED_SUPPORTED_FLAGS,
+			    &flags_bf, &userbits, extack);
+	if (err)
+		return err;
+
 	if (ctl->limit > 0) {
 		child = fifo_create_dflt(sch, &bfifo_qdisc_ops, ctl->limit,
 					 extack);
@@ -230,11 +275,17 @@ static int red_change(struct Qdisc *sch, struct nlattr *opt,
 	}
 
 	sch_tree_lock(sch);
-	q->flags = ctl->flags;
+
+	flags = (q->flags & ~flags_bf.selector) | flags_bf.value;
+	err = red_validate_flags(flags, extack);
+	if (err)
+		goto unlock_out;
+
+	q->flags = flags;
+	q->userbits = userbits;
 	q->limit = ctl->limit;
 	if (child) {
-		qdisc_tree_reduce_backlog(q->qdisc, q->qdisc->q.qlen,
-					  q->qdisc->qstats.backlog);
+		qdisc_purge_queue(q->qdisc);
 		old_child = q->qdisc;
 		q->qdisc = child;
 	}
@@ -242,11 +293,11 @@ static int red_change(struct Qdisc *sch, struct nlattr *opt,
 	red_set_parms(&q->parms,
 		      ctl->qth_min, ctl->qth_max, ctl->Wlog,
 		      ctl->Plog, ctl->Scell_log,
-		      nla_data(tb[TCA_RED_STAB]),
+		      stab,
 		      max_P);
 	red_set_vars(&q->vars);
 
-	del_timer(&q->adapt_timer);
+	timer_delete(&q->adapt_timer);
 	if (ctl->flags & TC_RED_ADAPTATIVE)
 		mod_timer(&q->adapt_timer, jiffies + HZ/2);
 
@@ -260,29 +311,86 @@ static int red_change(struct Qdisc *sch, struct nlattr *opt,
 	if (old_child)
 		qdisc_put(old_child);
 	return 0;
+
+unlock_out:
+	sch_tree_unlock(sch);
+	if (child)
+		qdisc_put(child);
+	return err;
 }
 
 static inline void red_adaptative_timer(struct timer_list *t)
 {
-	struct red_sched_data *q = from_timer(q, t, adapt_timer);
+	struct red_sched_data *q = timer_container_of(q, t, adapt_timer);
 	struct Qdisc *sch = q->sch;
-	spinlock_t *root_lock = qdisc_lock(qdisc_root_sleeping(sch));
+	spinlock_t *root_lock;
 
+	rcu_read_lock();
+	root_lock = qdisc_lock(qdisc_root_sleeping(sch));
 	spin_lock(root_lock);
 	red_adaptative_algo(&q->parms, &q->vars);
 	mod_timer(&q->adapt_timer, jiffies + HZ/2);
 	spin_unlock(root_lock);
+	rcu_read_unlock();
 }
 
 static int red_init(struct Qdisc *sch, struct nlattr *opt,
 		    struct netlink_ext_ack *extack)
 {
 	struct red_sched_data *q = qdisc_priv(sch);
+	struct nlattr *tb[TCA_RED_MAX + 1];
+	int err;
 
 	q->qdisc = &noop_qdisc;
 	q->sch = sch;
 	timer_setup(&q->adapt_timer, red_adaptative_timer, 0);
-	return red_change(sch, opt, extack);
+
+	if (!opt)
+		return -EINVAL;
+
+	err = nla_parse_nested_deprecated(tb, TCA_RED_MAX, opt, red_policy,
+					  extack);
+	if (err < 0)
+		return err;
+
+	err = __red_change(sch, tb, extack);
+	if (err)
+		return err;
+
+	err = tcf_qevent_init(&q->qe_early_drop, sch,
+			      FLOW_BLOCK_BINDER_TYPE_RED_EARLY_DROP,
+			      tb[TCA_RED_EARLY_DROP_BLOCK], extack);
+	if (err)
+		return err;
+
+	return tcf_qevent_init(&q->qe_mark, sch,
+			       FLOW_BLOCK_BINDER_TYPE_RED_MARK,
+			       tb[TCA_RED_MARK_BLOCK], extack);
+}
+
+static int red_change(struct Qdisc *sch, struct nlattr *opt,
+		      struct netlink_ext_ack *extack)
+{
+	struct red_sched_data *q = qdisc_priv(sch);
+	struct nlattr *tb[TCA_RED_MAX + 1];
+	int err;
+
+	err = nla_parse_nested_deprecated(tb, TCA_RED_MAX, opt, red_policy,
+					  extack);
+	if (err < 0)
+		return err;
+
+	err = tcf_qevent_validate_change(&q->qe_early_drop,
+					 tb[TCA_RED_EARLY_DROP_BLOCK], extack);
+	if (err)
+		return err;
+
+	err = tcf_qevent_validate_change(&q->qe_mark,
+					 tb[TCA_RED_MARK_BLOCK], extack);
+	if (err)
+		return err;
+
+	return __red_change(sch, tb, extack);
 }
 
 static int red_dump_offload_stats(struct Qdisc *sch)
@@ -306,7 +414,8 @@ static int red_dump(struct Qdisc *sch, struct sk_buff *skb)
 	struct nlattr *opts = NULL;
 	struct tc_red_qopt opt = {
 		.limit		= q->limit,
-		.flags		= q->flags,
+		.flags		= (q->flags & TC_RED_HISTORIC_FLAGS) |
+				  q->userbits,
 		.qth_min	= q->parms.qth_min >> q->parms.Wlog,
 		.qth_max	= q->parms.qth_max >> q->parms.Wlog,
 		.Wlog		= q->parms.Wlog,
@@ -319,11 +428,15 @@ static int red_dump(struct Qdisc *sch, struct sk_buff *skb)
 	if (err)
 		goto nla_put_failure;
 
-	opts = nla_nest_start(skb, TCA_OPTIONS);
+	opts = nla_nest_start_noflag(skb, TCA_OPTIONS);
 	if (opts == NULL)
 		goto nla_put_failure;
 	if (nla_put(skb, TCA_RED_PARMS, sizeof(opt), &opt) ||
-	    nla_put_u32(skb, TCA_RED_MAX_P, q->parms.max_P))
+	    nla_put_u32(skb, TCA_RED_MAX_P, q->parms.max_P) ||
+	    nla_put_bitfield32(skb, TCA_RED_FLAGS,
+			       q->flags, TC_RED_SUPPORTED_FLAGS) ||
+	    tcf_qevent_dump(skb, TCA_RED_MARK_BLOCK, &q->qe_mark) ||
+	    tcf_qevent_dump(skb, TCA_RED_EARLY_DROP_BLOCK, &q->qe_early_drop))
 		goto nla_put_failure;
 	return nla_nest_end(skb, opts);
 
@@ -352,7 +465,6 @@ static int red_dump_stats(struct Qdisc *sch, struct gnet_dump *d)
 	}
 	st.early = q->stats.prob_drop + q->stats.forced_drop;
 	st.pdrop = q->stats.pdrop;
-	st.other = q->stats.other;
 	st.marked = q->stats.prob_mark + q->stats.forced_mark;
 
 	return gnet_stats_copy_app(d, &st, sizeof(st));
@@ -411,12 +523,7 @@ static unsigned long red_find(struct Qdisc *sch, u32 classid)
 static void red_walk(struct Qdisc *sch, struct qdisc_walker *walker)
 {
 	if (!walker->stop) {
-		if (walker->count >= walker->skip)
-			if (walker->fn(sch, 1, walker) < 0) {
-				walker->stop = 1;
-				return;
-			}
-		walker->count++;
+		tc_qdisc_stats_dump(sch, 1, walker);
 	}
 }
 
@@ -443,6 +550,7 @@ static struct Qdisc_ops red_qdisc_ops __read_mostly = {
 	.dump_stats	=	red_dump_stats,
 	.owner		=	THIS_MODULE,
 };
+MODULE_ALIAS_NET_SCH("red");
 
 static int __init red_module_init(void)
 {
@@ -458,3 +566,4 @@ module_init(red_module_init)
 module_exit(red_module_exit)
 
 MODULE_LICENSE("GPL");
+MODULE_DESCRIPTION("Random Early Detection qdisc");