ixgbe: no need for esp trailer if GSO

There is no need to calculate the trailer length if we're doing
a GSO/TSO, as there is no trailer added to the packet data.
Also, don't bother clearing the flags field as it was already
cleared earlier.

Signed-off-by: Shannon Nelson <shannon.nelson@oracle.com>
Tested-by: Andrew Bowers <andrewx.bowers@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>

diff --git a/drivers/net/ethernet/intel/ixgbe/ixgbe_ipsec.c b/drivers/net/ethernet/intel/ixgbe/ixgbe_ipsec.c
index f2254528dcfcdfac5e2a877b7558f8b9d6a3ed08..5ddea43a21c231fb829f8be373c407f9cf3fb2d8 100644 (file)
--- a/drivers/net/ethernet/intel/ixgbe/ixgbe_ipsec.c
+++ b/drivers/net/ethernet/intel/ixgbe/ixgbe_ipsec.c
@@ -774,11 +774,7 @@ int ixgbe_ipsec_tx(struct ixgbe_ring *tx_ring,
 
        first->tx_flags |= IXGBE_TX_FLAGS_IPSEC | IXGBE_TX_FLAGS_CC;
 
-       itd->flags = 0;
        if (xs->id.proto == IPPROTO_ESP) {
-               struct sk_buff *skb = first->skb;
-               int ret, authlen, trailerlen;
-               u8 padlen;
 
                itd->flags |= IXGBE_ADVTXD_TUCMD_IPSEC_TYPE_ESP |
                              IXGBE_ADVTXD_TUCMD_L4T_TCP;
@@ -790,19 +786,28 @@ int ixgbe_ipsec_tx(struct ixgbe_ring *tx_ring,
                 * padlen bytes of padding.  This ends up not the same
                 * as the static value found in xs->props.trailer_len (21).
                 *
-                * The "correct" way to get the auth length would be to use
-                *    authlen = crypto_aead_authsize(xs->data);
-                * but since we know we only have one size to worry about
-                * we can let the compiler use the constant and save us a
-                * few CPU cycles.
+                * ... but if we're doing GSO, don't bother as the stack
+                * doesn't add a trailer for those.
                 */
-               authlen = IXGBE_IPSEC_AUTH_BITS / 8;
-
-               ret = skb_copy_bits(skb, skb->len - (authlen + 2), &padlen, 1);
-               if (unlikely(ret))
-                       return 0;
-               trailerlen = authlen + 2 + padlen;
-               itd->trailer_len = trailerlen;
+               if (!skb_is_gso(first->skb)) {
+                       /* The "correct" way to get the auth length would be
+                        * to use
+                        *    authlen = crypto_aead_authsize(xs->data);
+                        * but since we know we only have one size to worry
+                        * about * we can let the compiler use the constant
+                        * and save us a few CPU cycles.
+                        */
+                       const int authlen = IXGBE_IPSEC_AUTH_BITS / 8;
+                       struct sk_buff *skb = first->skb;
+                       u8 padlen;
+                       int ret;
+
+                       ret = skb_copy_bits(skb, skb->len - (authlen + 2),
+                                           &padlen, 1);
+                       if (unlikely(ret))
+                               return 0;
+                       itd->trailer_len = authlen + 2 + padlen;
+               }
        }
        if (tsa->encrypt)
                itd->flags |= IXGBE_ADVTXD_TUCMD_IPSEC_ENCRYPT_EN;