[BLUETOOTH] lockdep: annotate sk_lock nesting in AF_BLUETOOTH

=============================================
[ INFO: possible recursive locking detected ]
2.6.18-1.2726.fc6 #1

include/net/sock.h

@@ -745,7 +745,13 @@ static inline int sk_stream_wmem_schedule(struct sock *sk, int size)
  */
 #define sock_owned_by_user(sk)	((sk)->sk_lock.owner)
 
-extern void FASTCALL(lock_sock(struct sock *sk));
+extern void FASTCALL(lock_sock_nested(struct sock *sk, int subclass));
+
+static inline void lock_sock(struct sock *sk)
+{
+	lock_sock_nested(sk, 0);
+}
+
 extern void FASTCALL(release_sock(struct sock *sk));
 
 /* BH context may only use the following locking interface. */

net/bluetooth/l2cap.c

@@ -770,7 +770,7 @@ static int l2cap_sock_accept(struct socket *sock, struct socket *newsock, int fl
 	long timeo;
 	int err = 0;
 
-	lock_sock(sk);
+	lock_sock_nested(sk, SINGLE_DEPTH_NESTING);
 
 	if (sk->sk_state != BT_LISTEN) {
 		err = -EBADFD;
@@ -792,7 +792,7 @@ static int l2cap_sock_accept(struct socket *sock, struct socket *newsock, int fl
 
 		release_sock(sk);
 		timeo = schedule_timeout(timeo);
-		lock_sock(sk);
+		lock_sock_nested(sk, SINGLE_DEPTH_NESTING);
 
 		if (sk->sk_state != BT_LISTEN) {
 			err = -EBADFD;

net/core/sock.c

@@ -1527,7 +1527,7 @@ void sock_init_data(struct socket *sock, struct sock *sk)
 	atomic_set(&sk->sk_refcnt, 1);
 }
 
-void fastcall lock_sock(struct sock *sk)
+void fastcall lock_sock_nested(struct sock *sk, int subclass)
 {
 	might_sleep();
 	spin_lock_bh(&sk->sk_lock.slock);
@@ -1538,11 +1538,11 @@ void fastcall lock_sock(struct sock *sk)
 	/*
 	 * The sk_lock has mutex_lock() semantics here:
 	 */
-	mutex_acquire(&sk->sk_lock.dep_map, 0, 0, _RET_IP_);
+	mutex_acquire(&sk->sk_lock.dep_map, subclass, 0, _RET_IP_);
 	local_bh_enable();
 }
 
-EXPORT_SYMBOL(lock_sock);
+EXPORT_SYMBOL(lock_sock_nested);
 
 void fastcall release_sock(struct sock *sk)
 {