[Quantal][PATCH 17/29] be2net: dont pull too much data in skb linear part

[Jesse Sung]

From: Eric Dumazet <edumazet at google.com>

BugLink: https://launchpad.net/bugs/1083088

skb_fill_rx_data() pulls 64 byte of data in skb->data

Its too much for TCP (with no options) on IPv4, as total size of headers
is 14 + 40 = 54

This means tcp stack and splice() are suboptimal, since tcp payload
is in part in tcp->data, and in part in skb frag.

Signed-off-by: Eric Dumazet <edumazet at google.com>
Acked-by: Padmanabh Ratnakar <padmanabh.ratnakar at emulex.com>
Signed-off-by: David S. Miller <davem at davemloft.net>
(cherry picked from commit ac1ae5f33fd225f46da0072e2091962410a0431b)

Signed-off-by: Wen-chien Jesse Sung <jesse.sung at canonical.com>
---
 drivers/net/ethernet/emulex/benet/be_main.c |    6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/drivers/net/ethernet/emulex/benet/be_main.c b/drivers/net/ethernet/emulex/benet/be_main.c
index 5919408..7bf6d1d 100644
--- a/drivers/net/ethernet/emulex/benet/be_main.c
+++ b/drivers/net/ethernet/emulex/benet/be_main.c
@@ -1228,16 +1228,16 @@ static void skb_fill_rx_data(struct be_rx_obj *rxo, struct sk_buff *skb,
 	/* Copy data in the first descriptor of this completion */
 	curr_frag_len = min(rxcp->pkt_size, rx_frag_size);
 
-	/* Copy the header portion into skb_data */
-	hdr_len = min(BE_HDR_LEN, curr_frag_len);
-	memcpy(skb->data, start, hdr_len);
 	skb->len = curr_frag_len;
 	if (curr_frag_len <= BE_HDR_LEN) { /* tiny packet */
+		memcpy(skb->data, start, curr_frag_len);
 		/* Complete packet has now been moved to data */
 		put_page(page_info->page);
 		skb->data_len = 0;
 		skb->tail += curr_frag_len;
 	} else {
+		hdr_len = ETH_HLEN;
+		memcpy(skb->data, start, hdr_len);
 		skb_shinfo(skb)->nr_frags = 1;
 		skb_frag_set_page(skb, 0, page_info->page);
 		skb_shinfo(skb)->frags[0].page_offset =
-- 
1.7.10.4