nfp: rename l4_offset in struct nfp_net_tx_desc to lso_hdrlen

The l4_offset field referred to by NFD is confusingly named. It is not the
offset of the L4 transport header, but rather the L4 payload.

The LSO2 capability supported by alternative device firmware requires
the actual L4 offset, thus the rename seems prudent.
Signed-off-by: NEdwin Peer <edwin.peer@netronome.com>
Reviewed-by: NJakub Kicinski <jakub.kicinski@netronome.com>
Reviewed-by: NSimon Horman <simon.horman@netronome.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

drivers/net/ethernet/netronome/nfp/nfp_net.h

@@ -153,7 +153,7 @@ struct nfp_net_tx_desc {
 			__le32 dma_addr_lo; /* Low 32bit of host buf addr */
 
 			__le16 mss;	/* MSS to be used for LSO */
-			u8 l4_offset;	/* LSO, where the L4 data starts */
+			u8 lso_hdrlen;	/* LSO, TCP payload offset */
 			u8 flags;	/* TX Flags, see @PCIE_DESC_TX_* */
 
 			__le16 vlan;	/* VLAN tag to add if indicated */

drivers/net/ethernet/netronome/nfp/nfp_net_common.c

@@ -677,7 +677,7 @@ static void nfp_net_tx_tso(struct nfp_net_r_vector *r_vec,
 	txbuf->real_len += hdrlen * (txbuf->pkt_cnt - 1);
 
 	mss = skb_shinfo(skb)->gso_size & PCIE_DESC_TX_MSS_MASK;
-	txd->l4_offset = hdrlen;
+	txd->lso_hdrlen = hdrlen;
 	txd->mss = cpu_to_le16(mss);
 	txd->flags |= PCIE_DESC_TX_LSO;
 
@@ -823,7 +823,7 @@ static int nfp_net_tx(struct sk_buff *skb, struct net_device *netdev)
 
 	txd->flags = 0;
 	txd->mss = 0;
-	txd->l4_offset = 0;
+	txd->lso_hdrlen = 0;
 
 	nfp_net_tx_tso(r_vec, txbuf, txd, skb);
 
@@ -1515,7 +1515,7 @@ nfp_net_tx_xdp_buf(struct nfp_net_dp *dp, struct nfp_net_rx_ring *rx_ring,
 
 	txd->flags = 0;
 	txd->mss = 0;
-	txd->l4_offset = 0;
+	txd->lso_hdrlen = 0;
 
 	tx_ring->wr_p++;
 	tx_ring->wr_ptr_add++;