ipv6: move IPV6_TCLASS_SHIFT into ipv6.h and define a helper

Two places defined IPV6_TCLASS_SHIFT, so we should move it into ipv6.h,
and use this macro as possible. And define ip6_tclass helper to return
tclass

Signed-off-by: Li RongQing <roy.qing.li@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 5 insertions, 0 deletions

diff --git a/include/net/ipv6.h b/include/net/ipv6.h
index 12079c65ea3e..6d80f51897a5 100644
--- a/include/net/ipv6.h
+++ b/include/net/ipv6.h
@@ -239,6 +239,7 @@ struct ip6_flowlabel {
 #define IPV6_FLOWINFO_MASK      cpu_to_be32(0x0FFFFFFF)
 #define IPV6_FLOWLABEL_MASK     cpu_to_be32(0x000FFFFF)
 #define IPV6_TCLASS_MASK (IPV6_FLOWINFO_MASK & ~IPV6_FLOWLABEL_MASK)
+#define IPV6_TCLASS_SHIFT       20
 
 struct ipv6_fl_socklist {
         struct ipv6_fl_socklist __rcu   *next;
@@ -681,6 +682,10 @@ static inline __be32 ip6_flowlabel(const struct ipv6hdr *hdr)
         return *(__be32 *)hdr & IPV6_FLOWLABEL_MASK;
 }
 
+static inline u8 ip6_tclass(__be32 flowinfo)
+{
+        return ntohl(flowinfo & IPV6_TCLASS_MASK) >> IPV6_TCLASS_SHIFT;
+}
 /*
  *      Prototypes exported by ipv6
  */