[INET]: Remove struct dst_entry *dst from request_sock_ops.rtx_syn_ack.

It looks like dst parameter is used in this API due to historical
reasons.  Actually, it is really used in the direct call to
tcp_v4_send_synack only.  So, create a wrapper for tcp_v4_send_synack
and remove dst from rtx_syn_ack.

Signed-off-by: Denis V. Lunev <den@openvz.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

8 files changed, 53 insertions, 55 deletions

diff --git a/include/net/request_sock.h b/include/net/request_sock.h
index cff4608179c1..040780add355 100644
--- a/include/net/request_sock.h
+++ b/include/net/request_sock.h
@@ -31,8 +31,7 @@ struct request_sock_ops {
         int             obj_size;
         struct kmem_cache       *slab;
         int             (*rtx_syn_ack)(struct sock *sk,
-                                       struct request_sock *req,
-                                       struct dst_entry *dst);
+                                       struct request_sock *req);
         void            (*send_ack)(struct sk_buff *skb,
                                     struct request_sock *req);
         void            (*send_reset)(struct sock *sk,
diff --git a/net/dccp/ipv4.c b/net/dccp/ipv4.c
index 474075adbde4..514a40b7fc7f 100644
--- a/net/dccp/ipv4.c
+++ b/net/dccp/ipv4.c
@@ -471,15 +471,14 @@ static struct dst_entry* dccp_v4_route_skb(struct sock *sk,
         return &rt->u.dst;
 }
 
-static int dccp_v4_send_response(struct sock *sk, struct request_sock *req,
-                                 struct dst_entry *dst)
+static int dccp_v4_send_response(struct sock *sk, struct request_sock *req)
 {
         int err = -1;
         struct sk_buff *skb;
+        struct dst_entry *dst;
 
-        /* First, grab a route. */
-
-        if (dst == NULL && (dst = inet_csk_route_req(sk, req)) == NULL)
+        dst = inet_csk_route_req(sk, req);
+        if (dst == NULL)
                 goto out;
 
         skb = dccp_make_response(sk, dst, req);
@@ -620,7 +619,7 @@ int dccp_v4_conn_request(struct sock *sk, struct sk_buff *skb)
         dreq->dreq_iss     = dccp_v4_init_sequence(skb);
         dreq->dreq_service = service;
 
-        if (dccp_v4_send_response(sk, req, NULL))
+        if (dccp_v4_send_response(sk, req))
                 goto drop_and_free;
 
         inet_csk_reqsk_queue_hash_add(sk, req, DCCP_TIMEOUT_INIT);
diff --git a/net/dccp/ipv6.c b/net/dccp/ipv6.c
index 490333d47c7b..1a5e50b90677 100644
--- a/net/dccp/ipv6.c
+++ b/net/dccp/ipv6.c
@@ -224,8 +224,7 @@ out:
 }
 
 
-static int dccp_v6_send_response(struct sock *sk, struct request_sock *req,
-                                 struct dst_entry *dst)
+static int dccp_v6_send_response(struct sock *sk, struct request_sock *req)
 {
         struct inet6_request_sock *ireq6 = inet6_rsk(req);
         struct ipv6_pinfo *np = inet6_sk(sk);
@@ -234,6 +233,7 @@ static int dccp_v6_send_response(struct sock *sk, struct request_sock *req,
         struct in6_addr *final_p = NULL, final;
         struct flowi fl;
         int err = -1;
+        struct dst_entry *dst;
 
         memset(&fl, 0, sizeof(fl));
         fl.proto = IPPROTO_DCCP;
@@ -245,28 +245,26 @@ static int dccp_v6_send_response(struct sock *sk, struct request_sock *req,
         fl.fl_ip_sport = inet_sk(sk)->sport;
         security_req_classify_flow(req, &fl);
 
-        if (dst == NULL) {
-                opt = np->opt;
+        opt = np->opt;
 
-                if (opt != NULL && opt->srcrt != NULL) {
-                        const struct rt0_hdr *rt0 = (struct rt0_hdr *)opt->srcrt;
+        if (opt != NULL && opt->srcrt != NULL) {
+                const struct rt0_hdr *rt0 = (struct rt0_hdr *)opt->srcrt;
 
-                        ipv6_addr_copy(&final, &fl.fl6_dst);
-                        ipv6_addr_copy(&fl.fl6_dst, rt0->addr);
-                        final_p = &final;
-                }
+                ipv6_addr_copy(&final, &fl.fl6_dst);
+                ipv6_addr_copy(&fl.fl6_dst, rt0->addr);
+                final_p = &final;
+        }
 
-                err = ip6_dst_lookup(sk, &dst, &fl);
-                if (err)
-                        goto done;
+        err = ip6_dst_lookup(sk, &dst, &fl);
+        if (err)
+                goto done;
 
-                if (final_p)
-                        ipv6_addr_copy(&fl.fl6_dst, final_p);
+        if (final_p)
+                ipv6_addr_copy(&fl.fl6_dst, final_p);
 
-                err = xfrm_lookup(&dst, &fl, sk, 0);
-                if (err < 0)
-                        goto done;
-        }
+        err = xfrm_lookup(&dst, &fl, sk, 0);
+        if (err < 0)
+                goto done;
 
         skb = dccp_make_response(sk, dst, req);
         if (skb != NULL) {
@@ -448,7 +446,7 @@ static int dccp_v6_conn_request(struct sock *sk, struct sk_buff *skb)
         dreq->dreq_iss     = dccp_v6_init_sequence(skb);
         dreq->dreq_service = service;
 
-        if (dccp_v6_send_response(sk, req, NULL))
+        if (dccp_v6_send_response(sk, req))
                 goto drop_and_free;
 
         inet6_csk_reqsk_queue_hash_add(sk, req, DCCP_TIMEOUT_INIT);
diff --git a/net/dccp/minisocks.c b/net/dccp/minisocks.c
index 027d1814e1ab..33ad48321b08 100644
--- a/net/dccp/minisocks.c
+++ b/net/dccp/minisocks.c
@@ -216,7 +216,7 @@ struct sock *dccp_check_req(struct sock *sk, struct sk_buff *skb,
                          * counter (backoff, monitored by dccp_response_timer).
                          */
                         req->retrans++;
-                        req->rsk_ops->rtx_syn_ack(sk, req, NULL);
+                        req->rsk_ops->rtx_syn_ack(sk, req);
                 }
                 /* Network Duplicate, discard packet */
                 return NULL;
diff --git a/net/ipv4/inet_connection_sock.c b/net/ipv4/inet_connection_sock.c
index b189278c7bc1..c0e0fa03fce1 100644
--- a/net/ipv4/inet_connection_sock.c
+++ b/net/ipv4/inet_connection_sock.c
@@ -463,7 +463,7 @@ void inet_csk_reqsk_queue_prune(struct sock *parent,
                         if (time_after_eq(now, req->expires)) {
                                 if ((req->retrans < thresh ||
                                      (inet_rsk(req)->acked && req->retrans < max_retries))
-                                    && !req->rsk_ops->rtx_syn_ack(parent, req, NULL)) {
+                                    && !req->rsk_ops->rtx_syn_ack(parent, req)) {
                                         unsigned long timeo;
 
                                         if (req->retrans++ == 0)
diff --git a/net/ipv4/tcp_ipv4.c b/net/ipv4/tcp_ipv4.c
index 256032a41069..3b26f9586dcb 100644
--- a/net/ipv4/tcp_ipv4.c
+++ b/net/ipv4/tcp_ipv4.c
@@ -723,8 +723,8 @@ static void tcp_v4_reqsk_send_ack(struct sk_buff *skb,
  *      This still operates on a request_sock only, not on a big
  *      socket.
  */
-static int tcp_v4_send_synack(struct sock *sk, struct request_sock *req,
-                              struct dst_entry *dst)
+static int __tcp_v4_send_synack(struct sock *sk, struct request_sock *req,
+                                struct dst_entry *dst)
 {
         const struct inet_request_sock *ireq = inet_rsk(req);
         int err = -1;
@@ -732,7 +732,7 @@ static int tcp_v4_send_synack(struct sock *sk, struct request_sock *req,
 
         /* First, grab a route. */
         if (!dst && (dst = inet_csk_route_req(sk, req)) == NULL)
-                goto out;
+                return -1;
 
         skb = tcp_make_synack(sk, dst, req);
 
@@ -751,11 +751,15 @@ static int tcp_v4_send_synack(struct sock *sk, struct request_sock *req,
                 err = net_xmit_eval(err);
         }
 
-out:
         dst_release(dst);
         return err;
 }
 
+static int tcp_v4_send_synack(struct sock *sk, struct request_sock *req)
+{
+        return __tcp_v4_send_synack(sk, req, NULL);
+}
+
 /*
  *      IPv4 request_sock destructor.
  */
@@ -1380,7 +1384,7 @@ int tcp_v4_conn_request(struct sock *sk, struct sk_buff *skb)
         }
         tcp_rsk(req)->snt_isn = isn;
 
-        if (tcp_v4_send_synack(sk, req, dst))
+        if (__tcp_v4_send_synack(sk, req, dst))
                 goto drop_and_free;
 
         if (want_cookie) {
diff --git a/net/ipv4/tcp_minisocks.c b/net/ipv4/tcp_minisocks.c
index b61b76847ad9..0fdd1db641ac 100644
--- a/net/ipv4/tcp_minisocks.c
+++ b/net/ipv4/tcp_minisocks.c
@@ -536,7 +536,7 @@ struct sock *tcp_check_req(struct sock *sk,struct sk_buff *skb,
                  * Enforce "SYN-ACK" according to figure 8, figure 6
                  * of RFC793, fixed by RFC1122.
                  */
-                req->rsk_ops->rtx_syn_ack(sk, req, NULL);
+                req->rsk_ops->rtx_syn_ack(sk, req);
                 return NULL;
         }
 
diff --git a/net/ipv6/tcp_ipv6.c b/net/ipv6/tcp_ipv6.c
index 12750f2b05ab..1cbbb87dbad2 100644
--- a/net/ipv6/tcp_ipv6.c
+++ b/net/ipv6/tcp_ipv6.c
@@ -455,8 +455,7 @@ out:
 }
 
 
-static int tcp_v6_send_synack(struct sock *sk, struct request_sock *req,
-                              struct dst_entry *dst)
+static int tcp_v6_send_synack(struct sock *sk, struct request_sock *req)
 {
         struct inet6_request_sock *treq = inet6_rsk(req);
         struct ipv6_pinfo *np = inet6_sk(sk);
@@ -464,6 +463,7 @@ static int tcp_v6_send_synack(struct sock *sk, struct request_sock *req,
         struct ipv6_txoptions *opt = NULL;
         struct in6_addr * final_p = NULL, final;
         struct flowi fl;
+        struct dst_entry *dst;
         int err = -1;
 
         memset(&fl, 0, sizeof(fl));
@@ -476,24 +476,22 @@ static int tcp_v6_send_synack(struct sock *sk, struct request_sock *req,
         fl.fl_ip_sport = inet_sk(sk)->sport;
         security_req_classify_flow(req, &fl);
 
-        if (dst == NULL) {
-                opt = np->opt;
-                if (opt && opt->srcrt) {
-                        struct rt0_hdr *rt0 = (struct rt0_hdr *) opt->srcrt;
-                        ipv6_addr_copy(&final, &fl.fl6_dst);
-                        ipv6_addr_copy(&fl.fl6_dst, rt0->addr);
-                        final_p = &final;
-                }
-
-                err = ip6_dst_lookup(sk, &dst, &fl);
-                if (err)
-                        goto done;
-                if (final_p)
-                        ipv6_addr_copy(&fl.fl6_dst, final_p);
-                if ((err = xfrm_lookup(&dst, &fl, sk, 0)) < 0)
-                        goto done;
+        opt = np->opt;
+        if (opt && opt->srcrt) {
+                struct rt0_hdr *rt0 = (struct rt0_hdr *) opt->srcrt;
+                ipv6_addr_copy(&final, &fl.fl6_dst);
+                ipv6_addr_copy(&fl.fl6_dst, rt0->addr);
+                final_p = &final;
         }
 
+        err = ip6_dst_lookup(sk, &dst, &fl);
+        if (err)
+                goto done;
+        if (final_p)
+                ipv6_addr_copy(&fl.fl6_dst, final_p);
+        if ((err = xfrm_lookup(&dst, &fl, sk, 0)) < 0)
+                goto done;
+
         skb = tcp_make_synack(sk, dst, req);
         if (skb) {
                 struct tcphdr *th = tcp_hdr(skb);
@@ -1294,7 +1292,7 @@ static int tcp_v6_conn_request(struct sock *sk, struct sk_buff *skb)
 
         security_inet_conn_request(sk, skb, req);
 
-        if (tcp_v6_send_synack(sk, req, NULL))
+        if (tcp_v6_send_synack(sk, req))
                 goto drop;
 
         inet6_csk_reqsk_queue_hash_add(sk, req, TCP_TIMEOUT_INIT);