[NET]: Merge TSO/UFO fields in sk_buff

Having separate fields in sk_buff for TSO/UFO (tso_size/ufo_size) is not
going to scale if we add any more segmentation methods (e.g., DCCP).  So
let's merge them.

They were used to tell the protocol of a packet.  This function has been
subsumed by the new gso_type field.  This is essentially a set of netdev
feature bits (shifted by 16 bits) that are required to process a specific
skb.  As such it's easy to tell whether a given device can process a GSO
skb: you just have to and the gso_type field and the netdev's features
field.

I've made gso_type a conjunction.  The idea is that you have a base type
(e.g., SKB_GSO_TCPV4) that can be modified further to support new features.
For example, if we add a hardware TSO type that supports ECN, they would
declare NETIF_F_TSO | NETIF_F_TSO_ECN.  All TSO packets with CWR set would
have a gso_type of SKB_GSO_TCPV4 | SKB_GSO_TCPV4_ECN while all other TSO
packets would be SKB_GSO_TCPV4.  This means that only the CWR packets need
to be emulated in software.

Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 2 insertions, 2 deletions

diff --git a/drivers/net/ixgb/ixgb_main.c b/drivers/net/ixgb/ixgb_main.c
index 57006fb8840e..8bb32f946993 100644
--- a/drivers/net/ixgb/ixgb_main.c
+++ b/drivers/net/ixgb/ixgb_main.c
@@ -1173,7 +1173,7 @@ ixgb_tso(struct ixgb_adapter *adapter, struct sk_buff *skb)
         uint16_t ipcse, tucse, mss;
         int err;
 
-        if(likely(skb_shinfo(skb)->tso_size)) {
+        if(likely(skb_shinfo(skb)->gso_size)) {
                 if (skb_header_cloned(skb)) {
                         err = pskb_expand_head(skb, 0, 0, GFP_ATOMIC);
                         if (err)
@@ -1181,7 +1181,7 @@ ixgb_tso(struct ixgb_adapter *adapter, struct sk_buff *skb)
                 }
 
                 hdr_len = ((skb->h.raw - skb->data) + (skb->h.th->doff << 2));
-                mss = skb_shinfo(skb)->tso_size;
+                mss = skb_shinfo(skb)->gso_size;
                 skb->nh.iph->tot_len = 0;
                 skb->nh.iph->check = 0;
                 skb->h.th->check = ~csum_tcpudp_magic(skb->nh.iph->saddr,