datapath: Compatibility code for inet_proto_csum_replace2.

Kernels earlier than 2.6.25 did not define inet_proto_csum_replace2,
so implement it ourselves.

Signed-off-by: Jesse Gross <jesse@nicira.com>

diff --git a/datapath/linux-2.6/compat-2.6/include/net/checksum.h b/datapath/linux-2.6/compat-2.6/include/net/checksum.h
index a8c47d8..c2ffb34 100644 (file)
--- a/datapath/linux-2.6/compat-2.6/include/net/checksum.h
+++ b/datapath/linux-2.6/compat-2.6/include/net/checksum.h
@@ -25,6 +25,10 @@ static inline void csum_replace4(__sum16 *sum, __be32 from, __be32 to)
 
        sum = csum_fold(csum_partial((char *)diff, sizeof(diff), ~csum_unfold(*sum)));
 }
+
+#define inet_proto_csum_replace2(sum, skb, from, to, pseudohdr) \
+       inet_proto_csum_replace4(sum, skb, (__force __be32)(from), \
+                                          (__force __be32)(to), pseudohdr)
 #endif
 
 #endif /* checksum.h */