net-tc: convert tc_verd to integer bitfields

Extract the remaining two fields from tc_verd and remove the __u16
completely. TC_AT and TC_FROM are converted to equivalent two-bit
integer fields tc_at and tc_from. Where possible, use existing
helper skb_at_tc_ingress when reading tc_at. Introduce helper
skb_reset_tc to clear fields.

Not documenting tc_from and tc_at, because they will be replaced
with single bit fields in follow-on patches.

Signed-off-by: Willem de Bruijn <willemb@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

6 files changed, 13 insertions, 22 deletions

diff --git a/net/core/dev.c b/net/core/dev.c
index e39e35d2e082..8b5d6d033473 100644
--- a/net/core/dev.c
+++ b/net/core/dev.c
@@ -3153,7 +3153,7 @@ sch_handle_egress(struct sk_buff *skb, int *ret, struct net_device *dev)
 	if (!cl)
 		return skb;
 
-	/* skb->tc_verd and qdisc_skb_cb(skb)->pkt_len were already set
+	/* skb->tc_at and qdisc_skb_cb(skb)->pkt_len were already set
 	 * earlier by the caller.
 	 */
 	qdisc_bstats_cpu_update(cl->q, skb);
@@ -3320,7 +3320,7 @@ static int __dev_queue_xmit(struct sk_buff *skb, void *accel_priv)
 
 	qdisc_pkt_len_init(skb);
 #ifdef CONFIG_NET_CLS_ACT
-	skb->tc_verd = SET_TC_AT(skb->tc_verd, AT_EGRESS);
+	skb->tc_at = AT_EGRESS;
 # ifdef CONFIG_NET_EGRESS
 	if (static_key_false(&egress_needed)) {
 		skb = sch_handle_egress(skb, &rc, dev);
@@ -3920,7 +3920,7 @@ sch_handle_ingress(struct sk_buff *skb, struct packet_type **pt_prev, int *ret,
 	}
 
 	qdisc_skb_cb(skb)->pkt_len = skb->len;
-	skb->tc_verd = SET_TC_AT(skb->tc_verd, AT_INGRESS);
+	skb->tc_at = AT_INGRESS;
 	qdisc_bstats_cpu_update(cl->q, skb);
 
 	switch (tc_classify(skb, cl, &cl_res, false)) {
@@ -4122,9 +4122,7 @@ skip_taps:
 			goto out;
 	}
 #endif
-#ifdef CONFIG_NET_CLS_ACT
-	skb->tc_verd = 0;
-#endif
+	skb_reset_tc(skb);
 skip_classify:
 	if (pfmemalloc && !skb_pfmemalloc_protocol(skb))
 		goto drop;
diff --git a/net/core/pktgen.c b/net/core/pktgen.c
index 8e69ce472236..96947f5d41e4 100644
--- a/net/core/pktgen.c
+++ b/net/core/pktgen.c
@@ -3439,9 +3439,7 @@ static void pktgen_xmit(struct pktgen_dev *pkt_dev)
 			/* skb was 'freed' by stack, so clean few
 			 * bits and reuse it
 			 */
-#ifdef CONFIG_NET_CLS_ACT
-			skb->tc_verd = 0; /* reset reclass/redir ttl */
-#endif
+			skb_reset_tc(skb);
 		} while (--burst > 0);
 		goto out; /* Skips xmit_mode M_START_XMIT */
 	} else if (pkt_dev->xmit_mode == M_QUEUE_XMIT) {
diff --git a/net/core/skbuff.c b/net/core/skbuff.c
index 5a03730fbc1a..adec4bf807d8 100644
--- a/net/core/skbuff.c
+++ b/net/core/skbuff.c
@@ -878,9 +878,6 @@ static void __copy_skb_header(struct sk_buff *new, const struct sk_buff *old)
 #endif
 #ifdef CONFIG_NET_SCHED
 	CHECK_SKB_FIELD(tc_index);
-#ifdef CONFIG_NET_CLS_ACT
-	CHECK_SKB_FIELD(tc_verd);
-#endif
 #endif
 
 }
diff --git a/net/sched/act_ife.c b/net/sched/act_ife.c
index 80b848d3f096..921fb20eaa7c 100644
--- a/net/sched/act_ife.c
+++ b/net/sched/act_ife.c
@@ -736,12 +736,11 @@ static int tcf_ife_encode(struct sk_buff *skb, const struct tc_action *a,
 	u16 metalen = ife_get_sz(skb, ife);
 	int hdrm = metalen + skb->dev->hard_header_len + IFE_METAHDRLEN;
 	unsigned int skboff = skb->dev->hard_header_len;
-	u32 at = G_TC_AT(skb->tc_verd);
 	int new_len = skb->len + hdrm;
 	bool exceed_mtu = false;
 	int err;
 
-	if (at & AT_EGRESS) {
+	if (!skb_at_tc_ingress(skb)) {
 		if (new_len > skb->dev->mtu)
 			exceed_mtu = true;
 	}
@@ -773,7 +772,7 @@ static int tcf_ife_encode(struct sk_buff *skb, const struct tc_action *a,
 		return TC_ACT_SHOT;
 	}
 
-	if (!(at & AT_EGRESS))
+	if (skb_at_tc_ingress(skb))
 		skb_push(skb, skb->dev->hard_header_len);
 
 	iethh = (struct ethhdr *)skb->data;
@@ -816,7 +815,7 @@ static int tcf_ife_encode(struct sk_buff *skb, const struct tc_action *a,
 		ether_addr_copy(oethh->h_dest, iethh->h_dest);
 	oethh->h_proto = htons(ife->eth_type);
 
-	if (!(at & AT_EGRESS))
+	if (skb_at_tc_ingress(skb))
 		skb_pull(skb, skb->dev->hard_header_len);
 
 	spin_unlock(&ife->tcf_lock);
diff --git a/net/sched/act_mirred.c b/net/sched/act_mirred.c
index 2d9fa6e0a1b4..8543279bba49 100644
--- a/net/sched/act_mirred.c
+++ b/net/sched/act_mirred.c
@@ -170,7 +170,6 @@ static int tcf_mirred(struct sk_buff *skb, const struct tc_action *a,
 	int retval, err = 0;
 	int m_eaction;
 	int mac_len;
-	u32 at;
 
 	tcf_lastuse_update(&m->tcf_tm);
 	bstats_cpu_update(this_cpu_ptr(m->common.cpu_bstats), skb);
@@ -191,7 +190,6 @@ static int tcf_mirred(struct sk_buff *skb, const struct tc_action *a,
 		goto out;
 	}
 
-	at = G_TC_AT(skb->tc_verd);
 	skb2 = skb_clone(skb, GFP_ATOMIC);
 	if (!skb2)
 		goto out;
@@ -200,8 +198,9 @@ static int tcf_mirred(struct sk_buff *skb, const struct tc_action *a,
 	 * and devices expect a mac header on xmit, then mac push/pull is
 	 * needed.
 	 */
-	if (at != tcf_mirred_act_direction(m_eaction) && m_mac_header_xmit) {
-		if (at & AT_EGRESS) {
+	if (skb->tc_at != tcf_mirred_act_direction(m_eaction) &&
+	    m_mac_header_xmit) {
+		if (!skb_at_tc_ingress(skb)) {
 			/* caught at egress, act ingress: pull mac */
 			mac_len = skb_network_header(skb) - skb_mac_header(skb);
 			skb_pull_rcsum(skb2, mac_len);
@@ -213,7 +212,7 @@ static int tcf_mirred(struct sk_buff *skb, const struct tc_action *a,
 
 	/* mirror is always swallowed */
 	if (tcf_mirred_is_act_redirect(m_eaction))
-		skb2->tc_verd = SET_TC_FROM(skb2->tc_verd, at);
+		skb2->tc_from = skb2->tc_at;
 
 	skb2->skb_iif = skb->dev->ifindex;
 	skb2->dev = dev;
diff --git a/net/sched/sch_netem.c b/net/sched/sch_netem.c
index bcfadfdea8e0..bb5c638b6852 100644
--- a/net/sched/sch_netem.c
+++ b/net/sched/sch_netem.c
@@ -626,7 +626,7 @@ deliver:
 			 * If it's at ingress let's pretend the delay is
 			 * from the network (tstamp will be updated).
 			 */
-			if (G_TC_FROM(skb->tc_verd) & AT_INGRESS)
+			if (skb->tc_from & AT_INGRESS)
 				skb->tstamp = 0;
 #endif