sfc: Enable TSO for 802.1q VLAN devices

Signed-off-by: Ben Hutchings <bhutchings@solarflare.com>
Signed-off-by: Jeff Garzik <jgarzik@redhat.com>

1 files changed, 19 insertions, 6 deletions

diff --git a/drivers/net/sfc/tx.c b/drivers/net/sfc/tx.c
index 0e9889ca68fc..a3a3eddd30b9 100644
--- a/drivers/net/sfc/tx.c
+++ b/drivers/net/sfc/tx.c
@@ -105,7 +105,7 @@ struct efx_tso_header {
 };
 
 static int efx_enqueue_skb_tso(struct efx_tx_queue *tx_queue,
-                               const struct sk_buff *skb);
+                               struct sk_buff *skb);
 static void efx_fini_tso(struct efx_tx_queue *tx_queue);
 static void efx_tsoh_heap_free(struct efx_tx_queue *tx_queue,
                                struct efx_tso_header *tsoh);
@@ -139,7 +139,7 @@ static void efx_tsoh_free(struct efx_tx_queue *tx_queue,
  * You must hold netif_tx_lock() to call this function.
  */
 static int efx_enqueue_skb(struct efx_tx_queue *tx_queue,
-                           const struct sk_buff *skb)
+                           struct sk_buff *skb)
 {
         struct efx_nic *efx = tx_queue->efx;
         struct pci_dev *pci_dev = efx->pci_dev;
@@ -578,11 +578,24 @@ struct tso_state {
  * Verify that our various assumptions about sk_buffs and the conditions
  * under which TSO will be attempted hold true.
  */
-static void efx_tso_check_safe(const struct sk_buff *skb)
+static void efx_tso_check_safe(struct sk_buff *skb)
 {
-        EFX_BUG_ON_PARANOID(skb->protocol != htons(ETH_P_IP));
+        __be16 protocol = skb->protocol;
+
         EFX_BUG_ON_PARANOID(((struct ethhdr *)skb->data)->h_proto !=
-                            skb->protocol);
+                            protocol);
+        if (protocol == htons(ETH_P_8021Q)) {
+                /* Find the encapsulated protocol; reset network header
+                 * and transport header based on that. */
+                struct vlan_ethhdr *veh = (struct vlan_ethhdr *)skb->data;
+                protocol = veh->h_vlan_encapsulated_proto;
+                skb_set_network_header(skb, sizeof(*veh));
+                if (protocol == htons(ETH_P_IP))
+                        skb_set_transport_header(skb, sizeof(*veh) +
+                                                 4 * ip_hdr(skb)->ihl);
+        }
+
+        EFX_BUG_ON_PARANOID(protocol != htons(ETH_P_IP));
         EFX_BUG_ON_PARANOID(ip_hdr(skb)->protocol != IPPROTO_TCP);
         EFX_BUG_ON_PARANOID((PTR_DIFF(tcp_hdr(skb), skb->data)
                              + (tcp_hdr(skb)->doff << 2u)) >
@@ -1020,7 +1033,7 @@ static int tso_start_new_packet(struct efx_tx_queue *tx_queue,
  * %NETDEV_TX_OK or %NETDEV_TX_BUSY.
  */
 static int efx_enqueue_skb_tso(struct efx_tx_queue *tx_queue,
-                               const struct sk_buff *skb)
+                               struct sk_buff *skb)
 {
         struct efx_nic *efx = tx_queue->efx;
         int frag_i, rc, rc2 = NETDEV_TX_OK;