Merge branch 'listener_refactor'

Eric Dumazet says:

====================
inet: tcp listener refactoring, part 10

We are getting close to the point where request sockets will be hashed
into generic hash table. Some followups are needed for netfilter and
will be handled in next patch series.
====================

Signed-off-by: David S. Miller <davem@davemloft.net>

4 files changed, 26 insertions, 6 deletions

diff --git a/include/net/inet_connection_sock.h b/include/net/inet_connection_sock.h
index b9a6b0a94cc6..191feec60205 100644
--- a/include/net/inet_connection_sock.h
+++ b/include/net/inet_connection_sock.h
@@ -275,6 +275,11 @@ static inline void inet_csk_reqsk_queue_add(struct sock *sk,
 					    struct sock *child)
 {
 	reqsk_queue_add(&inet_csk(sk)->icsk_accept_queue, req, sk, child);
+	/* before letting lookups find us, make sure all req fields
+	 * are committed to memory.
+	 */
+	smp_wmb();
+	atomic_set(&req->rsk_refcnt, 1);
 }
 
 void inet_csk_reqsk_queue_hash_add(struct sock *sk, struct request_sock *req,
diff --git a/include/net/inet_sock.h b/include/net/inet_sock.h
index b3053fdd871e..3d8c09abb097 100644
--- a/include/net/inet_sock.h
+++ b/include/net/inet_sock.h
@@ -255,6 +255,11 @@ static inline struct request_sock *inet_reqsk_alloc(struct request_sock_ops *ops
 		ireq->opt = NULL;
 		atomic64_set(&ireq->ir_cookie, 0);
 		ireq->ireq_state = TCP_NEW_SYN_RECV;
+
+		/* Following is temporary. It is coupled with debugging
+		 * helpers in reqsk_put() & reqsk_free()
+		 */
+		atomic_set(&ireq->ireq_refcnt, 0);
 	}
 
 	return req;
diff --git a/include/net/request_sock.h b/include/net/request_sock.h
index 3275cf31f731..56dc2faba47e 100644
--- a/include/net/request_sock.h
+++ b/include/net/request_sock.h
@@ -82,19 +82,20 @@ static inline struct request_sock *inet_reqsk(struct sock *sk)
 	return (struct request_sock *)sk;
 }
 
-static inline void __reqsk_free(struct request_sock *req)
-{
-	kmem_cache_free(req->rsk_ops->slab, req);
-}
-
 static inline void reqsk_free(struct request_sock *req)
 {
+	/* temporary debugging */
+	WARN_ON_ONCE(atomic_read(&req->rsk_refcnt) != 0);
+
 	req->rsk_ops->destructor(req);
-	__reqsk_free(req);
+	kmem_cache_free(req->rsk_ops->slab, req);
 }
 
 static inline void reqsk_put(struct request_sock *req)
 {
+	/* temporary debugging, until req sock are put into ehash table */
+	WARN_ON_ONCE(atomic_read(&req->rsk_refcnt) != 1);
+
 	if (atomic_dec_and_test(&req->rsk_refcnt))
 		reqsk_free(req);
 }
diff --git a/include/net/sock.h b/include/net/sock.h
index f10832ca2e90..e0360f5a53e9 100644
--- a/include/net/sock.h
+++ b/include/net/sock.h
@@ -67,6 +67,7 @@
 #include <linux/atomic.h>
 #include <net/dst.h>
 #include <net/checksum.h>
+#include <net/tcp_states.h>
 #include <linux/net_tstamp.h>
 
 struct cgroup;
@@ -2218,6 +2219,14 @@ static inline struct sock *skb_steal_sock(struct sk_buff *skb)
 	return NULL;
 }
 
+/* This helper checks if a socket is a full socket,
+ * ie _not_ a timewait or request socket.
+ */
+static inline bool sk_fullsock(const struct sock *sk)
+{
+	return (1 << sk->sk_state) & ~(TCPF_TIME_WAIT | TCPF_NEW_SYN_RECV);
+}
+
 void sock_enable_timestamp(struct sock *sk, int flag);
 int sock_get_timestamp(struct sock *, struct timeval __user *);
 int sock_get_timestampns(struct sock *, struct timespec __user *);