net: rename sk_clone to sk_clone_lock

Make clear that sk_clone() and inet_csk_clone() return a locked socket.

Add _lock() prefix and kerneldoc.

Suggested-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

include/net/inet_connection_sock.h

@@ -143,9 +143,9 @@ static inline void *inet_csk_ca(const struct sock *sk)
 	return (void *)inet_csk(sk)->icsk_ca_priv;
 }
 
-extern struct sock *inet_csk_clone(struct sock *sk,
-				   const struct request_sock *req,
-				   const gfp_t priority);
+extern struct sock *inet_csk_clone_lock(const struct sock *sk,
+					const struct request_sock *req,
+					const gfp_t priority);
 
 enum inet_csk_ack_state_t {
 	ICSK_ACK_SCHED	= 1,

include/net/sock.h

@@ -1089,8 +1089,8 @@ extern struct sock		*sk_alloc(struct net *net, int family,
 					  struct proto *prot);
 extern void			sk_free(struct sock *sk);
 extern void			sk_release_kernel(struct sock *sk);
-extern struct sock		*sk_clone(const struct sock *sk,
-					  const gfp_t priority);
+extern struct sock		*sk_clone_lock(const struct sock *sk,
+					       const gfp_t priority);
 
 extern struct sk_buff		*sock_wmalloc(struct sock *sk,
 					      unsigned long size, int force,

net/core/sock.c

@@ -1204,7 +1204,14 @@ void sk_release_kernel(struct sock *sk)
 }
 EXPORT_SYMBOL(sk_release_kernel);
 
-struct sock *sk_clone(const struct sock *sk, const gfp_t priority)
+/**
+ *	sk_clone_lock - clone a socket, and lock its clone
+ *	@sk: the socket to clone
+ *	@priority: for allocation (%GFP_KERNEL, %GFP_ATOMIC, etc)
+ *
+ *	Caller must unlock socket even in error path (bh_unlock_sock(newsk))
+ */
+struct sock *sk_clone_lock(const struct sock *sk, const gfp_t priority)
 {
 	struct sock *newsk;
 
@@ -1297,7 +1304,7 @@ struct sock *sk_clone(const struct sock *sk, const gfp_t priority)
 out:
 	return newsk;
 }
-EXPORT_SYMBOL_GPL(sk_clone);
+EXPORT_SYMBOL_GPL(sk_clone_lock);
 
 void sk_setup_caps(struct sock *sk, struct dst_entry *dst)
 {

net/dccp/minisocks.c

@@ -100,7 +100,7 @@ struct sock *dccp_create_openreq_child(struct sock *sk,
 	 *   (* Generate a new socket and switch to that socket *)
 	 *   Set S := new socket for this port pair
 	 */
-	struct sock *newsk = inet_csk_clone(sk, req, GFP_ATOMIC);
+	struct sock *newsk = inet_csk_clone_lock(sk, req, GFP_ATOMIC);
 
 	if (newsk != NULL) {
 		struct dccp_request_sock *dreq = dccp_rsk(req);

net/ipv4/inet_connection_sock.c

@@ -588,10 +588,19 @@ void inet_csk_reqsk_queue_prune(struct sock *parent,
 }
 EXPORT_SYMBOL_GPL(inet_csk_reqsk_queue_prune);
 
-struct sock *inet_csk_clone(struct sock *sk, const struct request_sock *req,
-			    const gfp_t priority)
+/**
+ *	inet_csk_clone_lock - clone an inet socket, and lock its clone
+ *	@sk: the socket to clone
+ *	@req: request_sock
+ *	@priority: for allocation (%GFP_KERNEL, %GFP_ATOMIC, etc)
+ *
+ *	Caller must unlock socket even in error path (bh_unlock_sock(newsk))
+ */
+struct sock *inet_csk_clone_lock(const struct sock *sk,
+				 const struct request_sock *req,
+				 const gfp_t priority)
 {
-	struct sock *newsk = sk_clone(sk, priority);
+	struct sock *newsk = sk_clone_lock(sk, priority);
 
 	if (newsk != NULL) {
 		struct inet_connection_sock *newicsk = inet_csk(newsk);
@@ -615,7 +624,7 @@ struct sock *inet_csk_clone(struct sock *sk, const struct request_sock *req,
 	}
 	return newsk;
 }
-EXPORT_SYMBOL_GPL(inet_csk_clone);
+EXPORT_SYMBOL_GPL(inet_csk_clone_lock);
 
 /*
  * At this point, there should be no process reference to this

net/ipv4/tcp_minisocks.c

@@ -425,7 +425,7 @@ static inline void TCP_ECN_openreq_child(struct tcp_sock *tp,
  */
 struct sock *tcp_create_openreq_child(struct sock *sk, struct request_sock *req, struct sk_buff *skb)
 {
-	struct sock *newsk = inet_csk_clone(sk, req, GFP_ATOMIC);
+	struct sock *newsk = inet_csk_clone_lock(sk, req, GFP_ATOMIC);
 
 	if (newsk != NULL) {
 		const struct inet_request_sock *ireq = inet_rsk(req);