[PATCH net-next 4/5] qede: Add support to handle GRE hardware GRO packets

[Manish Chopra]

This patch adds support to do necessary processing
for hardware assisted GRE tunnel GRO packets before
driver delivers them upto the stack.

Signed-off-by: Manish Chopra <manish.cho...@qlogic.com>
Signed-off-by: Yuval Mintz <yuval.mi...@qlogic.com>
---
 drivers/net/ethernet/qlogic/qede/qede_main.c | 54 +++++++++++++++++++++++-----
 1 file changed, 46 insertions(+), 8 deletions(-)

diff --git a/drivers/net/ethernet/qlogic/qede/qede_main.c 
b/drivers/net/ethernet/qlogic/qede/qede_main.c
index a4b445f..787aef0 100644
--- a/drivers/net/ethernet/qlogic/qede/qede_main.c
+++ b/drivers/net/ethernet/qlogic/qede/qede_main.c
@@ -38,6 +38,7 @@
 #include <linux/bitops.h>
 #include <net/vxlan.h>
 #include <net/geneve.h>
+#include <net/gre.h>
 
 #include "qede.h"
 
@@ -1152,10 +1153,7 @@ cons_buf: /* We still need to handle bd_len_list to 
consume buffers */
 static void qede_gro_ip_csum(struct sk_buff *skb)
 {
        const struct iphdr *iph = ip_hdr(skb);
-       struct tcphdr *th;
-
-       skb_set_transport_header(skb, sizeof(struct iphdr));
-       th = tcp_hdr(skb);
+       struct tcphdr *th = tcp_hdr(skb);
 
        th->check = ~tcp_v4_check(skb->len - skb_transport_offset(skb),
                                  iph->saddr, iph->daddr, 0);
@@ -1166,10 +1164,7 @@ static void qede_gro_ip_csum(struct sk_buff *skb)
 static void qede_gro_ipv6_csum(struct sk_buff *skb)
 {
        struct ipv6hdr *iph = ipv6_hdr(skb);
-       struct tcphdr *th;
-
-       skb_set_transport_header(skb, sizeof(struct ipv6hdr));
-       th = tcp_hdr(skb);
+       struct tcphdr *th = tcp_hdr(skb);
 
        th->check = ~tcp_v6_check(skb->len - skb_transport_offset(skb),
                                  &iph->saddr, &iph->daddr, 0);
@@ -1232,6 +1227,44 @@ static void qede_handle_geneve_tunnel_gro(struct sk_buff 
*skb)
        }
 }
 
+static void qede_handle_gre_tunnel_gro(struct sk_buff *skb)
+{
+       unsigned int grehlen, gre_headroom;
+       struct gre_base_hdr *greh;
+       int nhoff = 0;
+
+       switch (skb->protocol) {
+       case htons(ETH_P_IP):
+               nhoff = sizeof(struct iphdr);
+               break;
+       case htons(ETH_P_IPV6):
+               nhoff = sizeof(struct ipv6hdr);
+               break;
+       default:
+               WARN_ONCE(1, "Unsupported GRE tunnel GRO, proto=0x%x\n",
+                         skb->protocol);
+       }
+
+       greh = (struct gre_base_hdr *)(skb->data + nhoff);
+       grehlen = sizeof(*greh);
+
+       if (greh->flags & GRE_KEY)
+               grehlen += GRE_HEADER_SECTION;
+
+       if (greh->flags & GRE_CSUM)
+               grehlen += GRE_HEADER_SECTION;
+
+       gre_headroom = nhoff + grehlen;
+
+       /* L2 GRE */
+       if (greh->protocol == htons(ETH_P_TEB))
+               gre_headroom += ETH_HLEN;
+
+       qede_set_nh_th_offset(skb, gre_headroom);
+
+       gre_gro_complete(skb, nhoff);
+}
+
 static void qede_handle_tunnel_gro(struct qede_dev *edev,
                                   struct sk_buff *skb, u8 tunnel_type)
 {
@@ -1242,6 +1275,9 @@ static void qede_handle_tunnel_gro(struct qede_dev *edev,
        case ETH_RX_TUNN_GENEVE:
                qede_handle_geneve_tunnel_gro(skb);
                break;
+       case ETH_RX_TUNN_GRE:
+               qede_handle_gre_tunnel_gro(skb);
+               break;
        default:
                WARN_ONCE(1, "Unsupported tunnel GRO, tunnel type=0x%x\n",
                          tunnel_type);
@@ -1277,9 +1313,11 @@ static void qede_gro_receive(struct qede_dev *edev,
 
                switch (skb->protocol) {
                case htons(ETH_P_IP):
+                       skb_set_transport_header(skb, sizeof(struct iphdr));
                        qede_gro_ip_csum(skb);
                        break;
                case htons(ETH_P_IPV6):
+                       skb_set_transport_header(skb, sizeof(struct ipv6hdr));
                        qede_gro_ipv6_csum(skb);
                        break;
                default:
-- 
2.7.2