inet: constify ip_dont_fragment() arguments

ip_dont_fragment() can accept const socket and dst

Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/include/net/ip.h b/include/net/ip.h
index 9b9ca28..525dc07 100644 (file)
--- a/include/net/ip.h
+++ b/include/net/ip.h
@@ -282,10 +282,12 @@ int ip_decrease_ttl(struct iphdr *iph)
 }
 
 static inline
-int ip_dont_fragment(struct sock *sk, struct dst_entry *dst)
+int ip_dont_fragment(const struct sock *sk, const struct dst_entry *dst)
 {
-       return  inet_sk(sk)->pmtudisc == IP_PMTUDISC_DO ||
-               (inet_sk(sk)->pmtudisc == IP_PMTUDISC_WANT &&
+       u8 pmtudisc = READ_ONCE(inet_sk(sk)->pmtudisc);
+
+       return  pmtudisc == IP_PMTUDISC_DO ||
+               (pmtudisc == IP_PMTUDISC_WANT &&
                 !(dst_metric_locked(dst, RTAX_MTU)));
 }