[UDP]: Allow users to configure UDP-Lite.

Let's give users an option for disabling UDP-Lite (~4K).

old:
|    text	   data	    bss	    dec	    hex	filename
|  286498	  12432	   6072	 305002	  4a76a	net/ipv4/built-in.o
|  193830	   8192	   3204	 205226	  321aa	net/ipv6/ipv6.o

new (without UDP-Lite):
|    text	   data	    bss	    dec	    hex	filename
|  284086	  12136	   5432	 301654	  49a56	net/ipv4/built-in.o
|  191835	   7832	   3076	 202743	  317f7	net/ipv6/ipv6.o

Signed-off-by: YOSHIFUJI Hideaki <yoshfuji@linux-ipv6.org>

1 files changed, 7 insertions, 2 deletions

diff --git a/include/net/udplite.h b/include/net/udplite.h
index b76b2e377af4..01ddb2c20264 100644
--- a/include/net/udplite.h
+++ b/include/net/udplite.h
@@ -25,7 +25,9 @@ static __inline__ int udplite_getfrag(void *from, char *to, int  offset,
 /* Designate sk as UDP-Lite socket */
 static inline int udplite_sk_init(struct sock *sk)
 {
+#ifdef CONFIG_IP_UDPLITE
         udp_sk(sk)->pcflag = UDPLITE_BIT;
+#endif
         return 0;
 }
 
@@ -69,7 +71,7 @@ static inline int udplite_checksum_init(struct sk_buff *skb, struct udphdr *uh)
 static inline int udplite_sender_cscov(struct udp_sock *up, struct udphdr *uh)
 {
         int cscov = up->len;
-
+#ifdef CONFIG_IP_UDPLITE
         /*
          * Sender has set `partial coverage' option on UDP-Lite socket
          */
@@ -93,13 +95,15 @@ static inline int udplite_sender_cscov(struct udp_sock *up, struct udphdr *uh)
          *       illegal, we fall back to the defaults here.
          */
         }
+#endif
         return cscov;
 }
 
 static inline __wsum udplite_csum_outgoing(struct sock *sk, struct sk_buff *skb)
 {
-        int cscov = udplite_sender_cscov(udp_sk(sk), udp_hdr(skb));
         __wsum csum = 0;
+#ifdef CONFIG_IP_UDPLITE
+        int cscov = udplite_sender_cscov(udp_sk(sk), udp_hdr(skb));
 
         skb->ip_summed = CHECKSUM_NONE;     /* no HW support for checksumming */
 
@@ -112,6 +116,7 @@ static inline __wsum udplite_csum_outgoing(struct sock *sk, struct sk_buff *skb)
                 if ((cscov -= len) <= 0)
                         break;
         }
+#endif
         return csum;
 }