From: Eric Dumazet <edumazet@google.com>
Date: Wed, 17 Jun 2020 20:53:25 -0700
Subject: net: tso: cache transport header length
Git-commit: 761b331cb6902dc0a08f786e9fa0dbd572059027
Patch-mainline: v5.9-rc1
References: jsc#SLE-16106

Add tlen field into struct tso_t, and change tso_start()
to return skb_transport_offset(skb) + tso->tlen

This removes from callers the need to use tcp_hdrlen(skb) and
will ease UDP segmentation offload addition.

v2: calls tso_start() earlier in otx2_sq_append_tso() [Jakub]

Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Acked-by: Nicolas Saenz Julienne <nsaenzjulienne@suse.de>
---
 drivers/net/ethernet/cavium/thunder/nicvf_queues.c |    5 +++--
 drivers/net/ethernet/freescale/fec_main.c          |    5 ++---
 drivers/net/ethernet/marvell/mv643xx_eth.c         |    5 ++---
 drivers/net/ethernet/marvell/mvneta.c              |    5 ++---
 drivers/net/ethernet/marvell/mvpp2/mvpp2_main.c    |    6 +++---
 include/net/tso.h                                  |    3 ++-
 net/core/tso.c                                     |   11 +++++++----
 7 files changed, 21 insertions(+), 19 deletions(-)

--- a/drivers/net/ethernet/cavium/thunder/nicvf_queues.c
+++ b/drivers/net/ethernet/cavium/thunder/nicvf_queues.c
@@ -1490,9 +1490,10 @@ static int nicvf_sq_append_tso(struct ni
 	int seg_subdescs = 0, desc_cnt = 0;
 	int seg_len, total_len, data_left;
 	int hdr_qentry = qentry;
-	int hdr_len = skb_transport_offset(skb) + tcp_hdrlen(skb);
+	int hdr_len;
+
+	hdr_len = tso_start(skb, &tso);
 
-	tso_start(skb, &tso);
 	total_len = skb->len - hdr_len;
 	while (total_len > 0) {
 		char *hdr;
--- a/drivers/net/ethernet/freescale/fec_main.c
+++ b/drivers/net/ethernet/freescale/fec_main.c
@@ -708,8 +708,7 @@ static int fec_enet_txq_submit_tso(struc
 				   struct net_device *ndev)
 {
 	struct fec_enet_private *fep = netdev_priv(ndev);
-	int hdr_len = skb_transport_offset(skb) + tcp_hdrlen(skb);
-	int total_len, data_left;
+	int hdr_len, total_len, data_left;
 	struct bufdesc *bdp = txq->bd.cur;
 	struct tso_t tso;
 	unsigned int index = 0;
@@ -729,7 +728,7 @@ static int fec_enet_txq_submit_tso(struc
 	}
 
 	/* Initialize the TSO handler, and prepare the first payload */
-	tso_start(skb, &tso);
+	hdr_len = tso_start(skb, &tso);
 
 	total_len = skb->len - hdr_len;
 	while (total_len > 0) {
--- a/drivers/net/ethernet/marvell/mv643xx_eth.c
+++ b/drivers/net/ethernet/marvell/mv643xx_eth.c
@@ -821,10 +821,9 @@ static int txq_submit_tso(struct tx_queu
 			  struct net_device *dev)
 {
 	struct mv643xx_eth_private *mp = txq_to_mp(txq);
-	int total_len, data_left, ret;
+	int hdr_len, total_len, data_left, ret;
 	int desc_count = 0;
 	struct tso_t tso;
-	int hdr_len = skb_transport_offset(skb) + tcp_hdrlen(skb);
 	struct tx_desc *first_tx_desc;
 	u32 first_cmd_sts = 0;
 
@@ -837,7 +836,7 @@ static int txq_submit_tso(struct tx_queu
 	first_tx_desc = &txq->tx_desc_area[txq->tx_curr_desc];
 
 	/* Initialize the TSO handler, and prepare the first payload */
-	tso_start(skb, &tso);
+	hdr_len = tso_start(skb, &tso);
 
 	total_len = skb->len - hdr_len;
 	while (total_len > 0) {
--- a/drivers/net/ethernet/marvell/mvneta.c
+++ b/drivers/net/ethernet/marvell/mvneta.c
@@ -2286,11 +2286,10 @@ mvneta_tso_put_data(struct net_device *d
 static int mvneta_tx_tso(struct sk_buff *skb, struct net_device *dev,
 			 struct mvneta_tx_queue *txq)
 {
-	int total_len, data_left;
+	int hdr_len, total_len, data_left;
 	int desc_count = 0;
 	struct mvneta_port *pp = netdev_priv(dev);
 	struct tso_t tso;
-	int hdr_len = skb_transport_offset(skb) + tcp_hdrlen(skb);
 	int i;
 
 	/* Count needed descriptors */
@@ -2303,7 +2302,7 @@ static int mvneta_tx_tso(struct sk_buff
 	}
 
 	/* Initialize the TSO handler, and prepare the first payload */
-	tso_start(skb, &tso);
+	hdr_len = tso_start(skb, &tso);
 
 	total_len = skb->len - hdr_len;
 	while (total_len > 0) {
--- a/drivers/net/ethernet/marvell/mvpp2/mvpp2_main.c
+++ b/drivers/net/ethernet/marvell/mvpp2/mvpp2_main.c
@@ -3157,9 +3157,8 @@ static int mvpp2_tx_tso(struct sk_buff *
 			struct mvpp2_txq_pcpu *txq_pcpu)
 {
 	struct mvpp2_port *port = netdev_priv(dev);
+	int hdr_sz, i, len, descs = 0;
 	struct tso_t tso;
-	int hdr_sz = skb_transport_offset(skb) + tcp_hdrlen(skb);
-	int i, len, descs = 0;
 
 	/* Check number of available descriptors */
 	if (mvpp2_aggr_desc_num_check(port, aggr_txq, tso_count_descs(skb)) ||
@@ -3167,7 +3166,8 @@ static int mvpp2_tx_tso(struct sk_buff *
 					     tso_count_descs(skb)))
 		return 0;
 
-	tso_start(skb, &tso);
+	hdr_sz = tso_start(skb, &tso);
+
 	len = skb->len - hdr_sz;
 	while (len > 0) {
 		int left = min_t(int, skb_shinfo(skb)->gso_size, len);
--- a/include/net/tso.h
+++ b/include/net/tso.h
@@ -11,6 +11,7 @@ struct tso_t {
 	void *data;
 	size_t size;
 	u16 ip_id;
+	u8	tlen; /* transport header len */
 	bool ipv6;
 	u32 tcp_seq;
 };
@@ -19,6 +20,6 @@ int tso_count_descs(struct sk_buff *skb)
 void tso_build_hdr(struct sk_buff *skb, char *hdr, struct tso_t *tso,
 		   int size, bool is_last);
 void tso_build_data(struct sk_buff *skb, struct tso_t *tso, int size);
-void tso_start(struct sk_buff *skb, struct tso_t *tso);
+int tso_start(struct sk_buff *skb, struct tso_t *tso);
 
 #endif	/* _TSO_H */
--- a/net/core/tso.c
+++ b/net/core/tso.c
@@ -17,7 +17,7 @@ void tso_build_hdr(struct sk_buff *skb,
 		   int size, bool is_last)
 {
 	struct tcphdr *tcph;
-	int hdr_len = skb_transport_offset(skb) + tcp_hdrlen(skb);
+	int hdr_len = skb_transport_offset(skb) + tso->tlen;
 	int mac_hdr_len = skb_network_offset(skb);
 
 	memcpy(hdr, skb->data, hdr_len);
@@ -30,7 +30,7 @@ void tso_build_hdr(struct sk_buff *skb,
 	} else {
 		struct ipv6hdr *iph = (void *)(hdr + mac_hdr_len);
 
-		iph->payload_len = htons(size + tcp_hdrlen(skb));
+		iph->payload_len = htons(size + tso->tlen);
 	}
 	tcph = (struct tcphdr *)(hdr + skb_transport_offset(skb));
 	put_unaligned_be32(tso->tcp_seq, &tcph->seq);
@@ -62,10 +62,12 @@ void tso_build_data(struct sk_buff *skb,
 }
 EXPORT_SYMBOL(tso_build_data);
 
-void tso_start(struct sk_buff *skb, struct tso_t *tso)
+int tso_start(struct sk_buff *skb, struct tso_t *tso)
 {
-	int hdr_len = skb_transport_offset(skb) + tcp_hdrlen(skb);
+	int tlen = tcp_hdrlen(skb);
+	int hdr_len = skb_transport_offset(skb) + tlen;
 
+	tso->tlen = tlen;
 	tso->ip_id = ntohs(ip_hdr(skb)->id);
 	tso->tcp_seq = ntohl(tcp_hdr(skb)->seq);
 	tso->next_frag_idx = 0;
@@ -83,5 +85,6 @@ void tso_start(struct sk_buff *skb, stru
 		tso->data = skb_frag_address(frag);
 		tso->next_frag_idx++;
 	}
+	return hdr_len;
 }
 EXPORT_SYMBOL(tso_start);