Commit ec624fe7 authored by Paul Blakey's avatar Paul Blakey Committed by Jakub Kicinski
Browse files

net/sched: Extend qdisc control block with tc control block 



BPF layer extends the qdisc control block via struct bpf_skb_data_end
and because of that there is no more room to add variables to the
qdisc layer control block without going over the skb->cb size.

Extend the qdisc control block with a tc control block,
and move all tc related variables to there as a pre-step for
extending the tc control block with additional members.

Signed-off-by: default avatarPaul Blakey <paulb@nvidia.com>
Signed-off-by: default avatarJakub Kicinski <kuba@kernel.org>
parent 8ca4090f

include/net/pkt_sched.h

+15 −0
Original line number Diff line number Diff line
@@ -193,4 +193,19 @@ static inline void skb_txtime_consumed(struct sk_buff *skb) 
	skb->tstamp = ktime_set(0, 0);

}



struct tc_skb_cb {

	struct qdisc_skb_cb qdisc_cb;



	u16 mru;

	bool post_ct;

};



static inline struct tc_skb_cb *tc_skb_cb(const struct sk_buff *skb)

{

	struct tc_skb_cb *cb = (struct tc_skb_cb *)skb->cb;



	BUILD_BUG_ON(sizeof(*cb) > sizeof_field(struct sk_buff, cb));

	return cb;

}



#endif

include/net/sch_generic.h

+0 −2
Original line number Diff line number Diff line
@@ -447,8 +447,6 @@ struct qdisc_skb_cb { 
	};

#define QDISC_CB_PRIV_LEN 20

	unsigned char		data[QDISC_CB_PRIV_LEN];

	u16			mru;

	bool			post_ct;

};



typedef void tcf_chain_head_change_t(struct tcf_proto *tp_head, void *priv);

net/core/dev.c

+4 −4
Original line number Diff line number Diff line
@@ -3941,8 +3941,8 @@ sch_handle_egress(struct sk_buff *skb, int *ret, struct net_device *dev) 
		return skb;



	/* qdisc_skb_cb(skb)->pkt_len was already set by the caller. */

	qdisc_skb_cb(skb)->mru = 0;

	qdisc_skb_cb(skb)->post_ct = false;

	tc_skb_cb(skb)->mru = 0;

	tc_skb_cb(skb)->post_ct = false;

	mini_qdisc_bstats_cpu_update(miniq, skb);



	switch (tcf_classify(skb, miniq->block, miniq->filter_list, &cl_res, false)) {
@@ -5103,8 +5103,8 @@ sch_handle_ingress(struct sk_buff *skb, struct packet_type **pt_prev, int *ret, 
	}



	qdisc_skb_cb(skb)->pkt_len = skb->len;

	qdisc_skb_cb(skb)->mru = 0;

	qdisc_skb_cb(skb)->post_ct = false;

	tc_skb_cb(skb)->mru = 0;

	tc_skb_cb(skb)->post_ct = false;

	skb->tc_at_ingress = 1;

	mini_qdisc_bstats_cpu_update(miniq, skb);

net/sched/act_ct.c

+7 −7
Original line number Diff line number Diff line
@@ -690,10 +690,10 @@ static int tcf_ct_handle_fragments(struct net *net, struct sk_buff *skb, 
				   u8 family, u16 zone, bool *defrag)

{

	enum ip_conntrack_info ctinfo;

	struct qdisc_skb_cb cb;

	struct nf_conn *ct;

	int err = 0;

	bool frag;

	u16 mru;



	/* Previously seen (loopback)? Ignore. */

	ct = nf_ct_get(skb, &ctinfo);
@@ -708,7 +708,7 @@ static int tcf_ct_handle_fragments(struct net *net, struct sk_buff *skb, 
		return err;



	skb_get(skb);

	cb = *qdisc_skb_cb(skb);

	mru = tc_skb_cb(skb)->mru;



	if (family == NFPROTO_IPV4) {

		enum ip_defrag_users user = IP_DEFRAG_CONNTRACK_IN + zone;
@@ -722,7 +722,7 @@ static int tcf_ct_handle_fragments(struct net *net, struct sk_buff *skb, 


		if (!err) {

			*defrag = true;

			cb.mru = IPCB(skb)->frag_max_size;

			mru = IPCB(skb)->frag_max_size;

		}

	} else { /* NFPROTO_IPV6 */

#if IS_ENABLED(CONFIG_NF_DEFRAG_IPV6)
@@ -735,7 +735,7 @@ static int tcf_ct_handle_fragments(struct net *net, struct sk_buff *skb, 


		if (!err) {

			*defrag = true;

			cb.mru = IP6CB(skb)->frag_max_size;

			mru = IP6CB(skb)->frag_max_size;

		}

#else

		err = -EOPNOTSUPP;
@@ -744,7 +744,7 @@ static int tcf_ct_handle_fragments(struct net *net, struct sk_buff *skb, 
	}



	if (err != -EINPROGRESS)

		*qdisc_skb_cb(skb) = cb;

		tc_skb_cb(skb)->mru = mru;

	skb_clear_hash(skb);

	skb->ignore_df = 1;

	return err;
@@ -963,7 +963,7 @@ static int tcf_ct_act(struct sk_buff *skb, const struct tc_action *a, 
	tcf_action_update_bstats(&c->common, skb);



	if (clear) {

		qdisc_skb_cb(skb)->post_ct = false;

		tc_skb_cb(skb)->post_ct = false;

		ct = nf_ct_get(skb, &ctinfo);

		if (ct) {

			nf_conntrack_put(&ct->ct_general);
@@ -1048,7 +1048,7 @@ static int tcf_ct_act(struct sk_buff *skb, const struct tc_action *a, 
out_push:

	skb_push_rcsum(skb, nh_ofs);



	qdisc_skb_cb(skb)->post_ct = true;

	tc_skb_cb(skb)->post_ct = true;

out_clear:

	if (defrag)

		qdisc_skb_cb(skb)->pkt_len = skb->len;

net/sched/cls_api.c

+4 −2
Original line number Diff line number Diff line
@@ -1617,12 +1617,14 @@ int tcf_classify(struct sk_buff *skb, 


	/* If we missed on some chain */

	if (ret == TC_ACT_UNSPEC && last_executed_chain) {

		struct tc_skb_cb *cb = tc_skb_cb(skb);



		ext = tc_skb_ext_alloc(skb);

		if (WARN_ON_ONCE(!ext))

			return TC_ACT_SHOT;

		ext->chain = last_executed_chain;

		ext->mru = qdisc_skb_cb(skb)->mru;

		ext->post_ct = qdisc_skb_cb(skb)->post_ct;

		ext->mru = cb->mru;

		ext->post_ct = cb->post_ct;

	}



	return ret;