net: remove duplicate sk_lookup helpers
[platform/kernel/linux-starfive.git] / net / ipv4 / inet_hashtables.c
index e7391bf..6a872b8 100644 (file)
@@ -28,9 +28,9 @@
 #include <net/tcp.h>
 #include <net/sock_reuseport.h>
 
-static u32 inet_ehashfn(const struct net *net, const __be32 laddr,
-                       const __u16 lport, const __be32 faddr,
-                       const __be16 fport)
+u32 inet_ehashfn(const struct net *net, const __be32 laddr,
+                const __u16 lport, const __be32 faddr,
+                const __be16 fport)
 {
        static u32 inet_ehash_secret __read_mostly;
 
@@ -39,6 +39,7 @@ static u32 inet_ehashfn(const struct net *net, const __be32 laddr,
        return __inet_ehashfn(laddr, lport, faddr, fport,
                              inet_ehash_secret + net_hash_mix(net));
 }
+EXPORT_SYMBOL_GPL(inet_ehashfn);
 
 /* This function handles inet_sock, but also timewait and request sockets
  * for IPv4/IPv6.
@@ -332,20 +333,40 @@ static inline int compute_score(struct sock *sk, struct net *net,
        return score;
 }
 
-static inline struct sock *lookup_reuseport(struct net *net, struct sock *sk,
-                                           struct sk_buff *skb, int doff,
-                                           __be32 saddr, __be16 sport,
-                                           __be32 daddr, unsigned short hnum)
+INDIRECT_CALLABLE_DECLARE(inet_ehashfn_t udp_ehashfn);
+
+/**
+ * inet_lookup_reuseport() - execute reuseport logic on AF_INET socket if necessary.
+ * @net: network namespace.
+ * @sk: AF_INET socket, must be in TCP_LISTEN state for TCP or TCP_CLOSE for UDP.
+ * @skb: context for a potential SK_REUSEPORT program.
+ * @doff: header offset.
+ * @saddr: source address.
+ * @sport: source port.
+ * @daddr: destination address.
+ * @hnum: destination port in host byte order.
+ * @ehashfn: hash function used to generate the fallback hash.
+ *
+ * Return: NULL if sk doesn't have SO_REUSEPORT set, otherwise a pointer to
+ *         the selected sock or an error.
+ */
+struct sock *inet_lookup_reuseport(struct net *net, struct sock *sk,
+                                  struct sk_buff *skb, int doff,
+                                  __be32 saddr, __be16 sport,
+                                  __be32 daddr, unsigned short hnum,
+                                  inet_ehashfn_t *ehashfn)
 {
        struct sock *reuse_sk = NULL;
        u32 phash;
 
        if (sk->sk_reuseport) {
-               phash = inet_ehashfn(net, daddr, hnum, saddr, sport);
+               phash = INDIRECT_CALL_2(ehashfn, udp_ehashfn, inet_ehashfn,
+                                       net, daddr, hnum, saddr, sport);
                reuse_sk = reuseport_select_sock(sk, phash, skb, doff);
        }
        return reuse_sk;
 }
+EXPORT_SYMBOL_GPL(inet_lookup_reuseport);
 
 /*
  * Here are some nice properties to exploit here. The BSD API
@@ -369,8 +390,8 @@ static struct sock *inet_lhash2_lookup(struct net *net,
        sk_nulls_for_each_rcu(sk, node, &ilb2->nulls_head) {
                score = compute_score(sk, net, hnum, daddr, dif, sdif);
                if (score > hiscore) {
-                       result = lookup_reuseport(net, sk, skb, doff,
-                                                 saddr, sport, daddr, hnum);
+                       result = inet_lookup_reuseport(net, sk, skb, doff,
+                                                      saddr, sport, daddr, hnum, inet_ehashfn);
                        if (result)
                                return result;
 
@@ -382,24 +403,23 @@ static struct sock *inet_lhash2_lookup(struct net *net,
        return result;
 }
 
-static inline struct sock *inet_lookup_run_bpf(struct net *net,
-                                              struct inet_hashinfo *hashinfo,
-                                              struct sk_buff *skb, int doff,
-                                              __be32 saddr, __be16 sport,
-                                              __be32 daddr, u16 hnum, const int dif)
+struct sock *inet_lookup_run_sk_lookup(struct net *net,
+                                      int protocol,
+                                      struct sk_buff *skb, int doff,
+                                      __be32 saddr, __be16 sport,
+                                      __be32 daddr, u16 hnum, const int dif,
+                                      inet_ehashfn_t *ehashfn)
 {
        struct sock *sk, *reuse_sk;
        bool no_reuseport;
 
-       if (hashinfo != net->ipv4.tcp_death_row.hashinfo)
-               return NULL; /* only TCP is supported */
-
-       no_reuseport = bpf_sk_lookup_run_v4(net, IPPROTO_TCP, saddr, sport,
+       no_reuseport = bpf_sk_lookup_run_v4(net, protocol, saddr, sport,
                                            daddr, hnum, dif, &sk);
        if (no_reuseport || IS_ERR_OR_NULL(sk))
                return sk;
 
-       reuse_sk = lookup_reuseport(net, sk, skb, doff, saddr, sport, daddr, hnum);
+       reuse_sk = inet_lookup_reuseport(net, sk, skb, doff, saddr, sport, daddr, hnum,
+                                        ehashfn);
        if (reuse_sk)
                sk = reuse_sk;
        return sk;
@@ -417,9 +437,11 @@ struct sock *__inet_lookup_listener(struct net *net,
        unsigned int hash2;
 
        /* Lookup redirect from BPF */
-       if (static_branch_unlikely(&bpf_sk_lookup_enabled)) {
-               result = inet_lookup_run_bpf(net, hashinfo, skb, doff,
-                                            saddr, sport, daddr, hnum, dif);
+       if (static_branch_unlikely(&bpf_sk_lookup_enabled) &&
+           hashinfo == net->ipv4.tcp_death_row.hashinfo) {
+               result = inet_lookup_run_sk_lookup(net, IPPROTO_TCP, skb, doff,
+                                                  saddr, sport, daddr, hnum, dif,
+                                                  inet_ehashfn);
                if (result)
                        goto done;
        }
@@ -650,20 +672,8 @@ bool inet_ehash_insert(struct sock *sk, struct sock *osk, bool *found_dup_sk)
        spin_lock(lock);
        if (osk) {
                WARN_ON_ONCE(sk->sk_hash != osk->sk_hash);
-               ret = sk_hashed(osk);
-               if (ret) {
-                       /* Before deleting the node, we insert a new one to make
-                        * sure that the look-up-sk process would not miss either
-                        * of them and that at least one node would exist in ehash
-                        * table all the time. Otherwise there's a tiny chance
-                        * that lookup process could find nothing in ehash table.
-                        */
-                       __sk_nulls_add_node_tail_rcu(sk, list);
-                       sk_nulls_del_node_init_rcu(osk);
-               }
-               goto unlock;
-       }
-       if (found_dup_sk) {
+               ret = sk_nulls_del_node_init_rcu(osk);
+       } else if (found_dup_sk) {
                *found_dup_sk = inet_ehash_lookup_by_sk(sk, list);
                if (*found_dup_sk)
                        ret = false;
@@ -672,7 +682,6 @@ bool inet_ehash_insert(struct sock *sk, struct sock *osk, bool *found_dup_sk)
        if (ret)
                __sk_nulls_add_node_rcu(sk, list);
 
-unlock:
        spin_unlock(lock);
 
        return ret;