[PATCH 4.4 40/45] ibmveth: calculate gso_segs for large packets

Greg Kroah-Hartman
2017-04-19T15:03:02Z

From: Thomas Falcon <tlfalcon@linux.vnet.ibm.com>

commit 94acf164dc8f1184e8d0737be7125134c2701dbe upstream.

Include calculations to compute the number of segments
that comprise an aggregated large packet.

Signed-off-by: Thomas Falcon <tlfalcon@linux.vnet.ibm.com>
Reviewed-by: Marcelo Ricardo Leitner <marcelo.leitner@gmail.com>
Reviewed-by: Jonathan Maxwell <jmaxwell37@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sumit Semwal <sumit.semwal@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

---
drivers/net/ethernet/ibm/ibmveth.c | 12 ++++++++++--
1 file changed, 10 insertions(+), 2 deletions(-)

--- a/drivers/net/ethernet/ibm/ibmveth.c
+++ b/drivers/net/ethernet/ibm/ibmveth.c
@@ -1179,7 +1179,9 @@ map_failed:

static void ibmveth_rx_mss_helper(struct sk_buff *skb, u16 mss, int lrg_pkt)
{
+ struct tcphdr *tcph;
int offset = 0;
+ int hdr_len;

/* only TCP packets will be aggregated */
if (skb->protocol == htons(ETH_P_IP)) {
@@ -1206,14 +1208,20 @@ static void ibmveth_rx_mss_helper(struct
/* if mss is not set through Large Packet bit/mss in rx buffer,
* expect that the mss will be written to the tcp header checksum.
*/
+ tcph = (struct tcphdr *)(skb->data + offset);
if (lrg_pkt) {
skb_shinfo(skb)->gso_size = mss;
} else if (offset) {
- struct tcphdr *tcph = (struct tcphdr *)(skb->data + offset);
-
skb_shinfo(skb)->gso_size = ntohs(tcph->check);
tcph->check = 0;
}
+
+ if (skb_shinfo(skb)->gso_size) {
+ hdr_len = offset + tcph->doff * 4;
+ skb_shinfo(skb)->gso_segs =
+ DIV_ROUND_UP(skb->len - hdr_len,
+ skb_shinfo(skb)->gso_size);
+ }
}

static int ibmveth_poll(struct napi_struct *napi, int budget)