net: use reciprocal_scale() helper

Replace open codings of (((u64) <x> * <y>) >> 32) with reciprocal_scale().

Signed-off-by: Daniel Borkmann <dborkman@redhat.com>
Cc: Hannes Frederic Sowa <hannes@stressinduktion.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

3 files changed, 5 insertions, 5 deletions

diff --git a/net/ipv4/inet_hashtables.c b/net/ipv4/inet_hashtables.c
index 43116e8c8e13..9111a4e22155 100644
--- a/net/ipv4/inet_hashtables.c
+++ b/net/ipv4/inet_hashtables.c
@@ -229,7 +229,7 @@ begin:
                         }
                 } else if (score == hiscore && reuseport) {
                         matches++;
-                        if (((u64)phash * matches) >> 32 == 0)
+                        if (reciprocal_scale(phash, matches) == 0)
                                 result = sk;
                         phash = next_pseudo_random32(phash);
                 }
diff --git a/net/ipv4/netfilter/ipt_CLUSTERIP.c b/net/ipv4/netfilter/ipt_CLUSTERIP.c
index 2510c02c2d21..e90f83a3415b 100644
--- a/net/ipv4/netfilter/ipt_CLUSTERIP.c
+++ b/net/ipv4/netfilter/ipt_CLUSTERIP.c
@@ -285,7 +285,7 @@ clusterip_hashfn(const struct sk_buff *skb,
         }
 
         /* node numbers are 1..n, not 0..n */
-        return (((u64)hashval * config->num_total_nodes) >> 32) + 1;
+        return reciprocal_scale(hashval, config->num_total_nodes) + 1;
 }
 
 static inline int
diff --git a/net/ipv4/udp.c b/net/ipv4/udp.c
index f57c0e4c2326..32f9571e776b 100644
--- a/net/ipv4/udp.c
+++ b/net/ipv4/udp.c
@@ -224,7 +224,7 @@ int udp_lib_get_port(struct sock *sk, unsigned short snum,
                 remaining = (high - low) + 1;
 
                 rand = prandom_u32();
-                first = (((u64)rand * remaining) >> 32) + low;
+                first = reciprocal_scale(rand, remaining) + low;
                 /*
                  * force rand to be an odd multiple of UDP_HTABLE_SIZE
                  */
@@ -448,7 +448,7 @@ begin:
                         }
                 } else if (score == badness && reuseport) {
                         matches++;
-                        if (((u64)hash * matches) >> 32 == 0)
+                        if (reciprocal_scale(hash, matches) == 0)
                                 result = sk;
                         hash = next_pseudo_random32(hash);
                 }
@@ -529,7 +529,7 @@ begin:
                         }
                 } else if (score == badness && reuseport) {
                         matches++;
-                        if (((u64)hash * matches) >> 32 == 0)
+                        if (reciprocal_scale(hash, matches) == 0)
                                 result = sk;
                         hash = next_pseudo_random32(hash);
                 }