ipv4: split inet_ehashfn to hash functions per compilation unit

This duplicates a bit of code but let's us easily introduce
separate secret keys later. The separate compilation units are
ipv4/inet_hashtabbles.o, ipv4/udp.o and rds/connection.o.

Cc: Eric Dumazet <edumazet@google.com>
Cc: "David S. Miller" <davem@davemloft.net>
Signed-off-by: Hannes Frederic Sowa <hannes@stressinduktion.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

4 files changed, 42 insertions, 23 deletions

diff --git a/include/net/inet_sock.h b/include/net/inet_sock.h
index 06da91efbc83..7a6c7f80a8fd 100644
--- a/include/net/inet_sock.h
+++ b/include/net/inet_sock.h
@@ -208,26 +208,16 @@ extern u32 inet_ehash_secret;
 extern u32 ipv6_hash_secret;
 void build_ehash_secret(void);
 
-static inline unsigned int inet_ehashfn(struct net *net,
-                                        const __be32 laddr, const __u16 lport,
-                                        const __be32 faddr, const __be16 fport)
+static inline unsigned int __inet_ehashfn(const __be32 laddr,
+                                          const __u16 lport,
+                                          const __be32 faddr,
+                                          const __be16 fport,
+                                          u32 initval)
 {
         return jhash_3words((__force __u32) laddr,
                             (__force __u32) faddr,
                             ((__u32) lport) << 16 | (__force __u32)fport,
-                            inet_ehash_secret + net_hash_mix(net));
-}
-
-static inline int inet_sk_ehashfn(const struct sock *sk)
-{
-        const struct inet_sock *inet = inet_sk(sk);
-        const __be32 laddr = inet->inet_rcv_saddr;
-        const __u16 lport = inet->inet_num;
-        const __be32 faddr = inet->inet_daddr;
-        const __be16 fport = inet->inet_dport;
-        struct net *net = sock_net(sk);
-
-        return inet_ehashfn(net, laddr, lport, faddr, fport);
+                            initval);
 }
 
 static inline struct request_sock *inet_reqsk_alloc(struct request_sock_ops *ops)
diff --git a/net/ipv4/inet_hashtables.c b/net/ipv4/inet_hashtables.c
index a4b66bbe4f21..18aa668d0cc9 100644
--- a/net/ipv4/inet_hashtables.c
+++ b/net/ipv4/inet_hashtables.c
@@ -24,6 +24,27 @@
 #include <net/secure_seq.h>
 #include <net/ip.h>
 
+static unsigned int inet_ehashfn(struct net *net, const __be32 laddr,
+                                 const __u16 lport, const __be32 faddr,
+                                 const __be16 fport)
+{
+        return __inet_ehashfn(laddr, lport, faddr, fport,
+                              inet_ehash_secret + net_hash_mix(net));
+}
+
+
+static unsigned int inet_sk_ehashfn(const struct sock *sk)
+{
+        const struct inet_sock *inet = inet_sk(sk);
+        const __be32 laddr = inet->inet_rcv_saddr;
+        const __u16 lport = inet->inet_num;
+        const __be32 faddr = inet->inet_daddr;
+        const __be16 fport = inet->inet_dport;
+        struct net *net = sock_net(sk);
+
+        return inet_ehashfn(net, laddr, lport, faddr, fport);
+}
+
 /*
  * Allocate and initialize a new local port bind bucket.
  * The bindhash mutex for snum's hash chain must be held here.
diff --git a/net/ipv4/udp.c b/net/ipv4/udp.c
index 9f27bb800607..b4437c7db6ce 100644
--- a/net/ipv4/udp.c
+++ b/net/ipv4/udp.c
@@ -407,6 +407,14 @@ static inline int compute_score2(struct sock *sk, struct net *net,
         return score;
 }
 
+static unsigned int udp_ehashfn(struct net *net, const __be32 laddr,
+                                 const __u16 lport, const __be32 faddr,
+                                 const __be16 fport)
+{
+        return __inet_ehashfn(laddr, lport, faddr, fport,
+                              inet_ehash_secret + net_hash_mix(net));
+}
+
 
 /* called with read_rcu_lock() */
 static struct sock *udp4_lib_lookup2(struct net *net,
@@ -430,8 +438,8 @@ begin:
                         badness = score;
                         reuseport = sk->sk_reuseport;
                         if (reuseport) {
-                                hash = inet_ehashfn(net, daddr, hnum,
-                                                    saddr, sport);
+                                hash = udp_ehashfn(net, daddr, hnum,
+                                                   saddr, sport);
                                 matches = 1;
                         }
                 } else if (score == badness && reuseport) {
@@ -511,8 +519,8 @@ begin:
                         badness = score;
                         reuseport = sk->sk_reuseport;
                         if (reuseport) {
-                                hash = inet_ehashfn(net, daddr, hnum,
-                                                    saddr, sport);
+                                hash = udp_ehashfn(net, daddr, hnum,
+                                                   saddr, sport);
                                 matches = 1;
                         }
                 } else if (score == badness && reuseport) {
diff --git a/net/rds/connection.c b/net/rds/connection.c
index 642ad42c416b..45e23660437a 100644
--- a/net/rds/connection.c
+++ b/net/rds/connection.c
@@ -52,9 +52,9 @@ static struct kmem_cache *rds_conn_slab;
 static struct hlist_head *rds_conn_bucket(__be32 laddr, __be32 faddr)
 {
         /* Pass NULL, don't need struct net for hash */
-        unsigned long hash = inet_ehashfn(NULL,
-                                          be32_to_cpu(laddr), 0,
-                                          be32_to_cpu(faddr), 0);
+        unsigned long hash = __inet_ehashfn(be32_to_cpu(laddr), 0,
+                                            be32_to_cpu(faddr), 0,
+                                            inet_ehash_secret);
         return &rds_conn_hash[hash & RDS_CONNECTION_HASH_MASK];
 }