net: sk_sleep() helper

Define a new function to return the waitqueue of a "struct sock".

static inline wait_queue_head_t *sk_sleep(struct sock *sk)
{
	return sk->sk_sleep;
}

Change all read occurrences of sk_sleep by a call to this function.

Needed for a future RCU conversion. sk_sleep wont be a field directly
available.

Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/bluetooth/af_bluetooth.c b/net/bluetooth/af_bluetooth.c
index 404a850..421c45b 100644
--- a/net/bluetooth/af_bluetooth.c
+++ b/net/bluetooth/af_bluetooth.c
@@ -288,7 +288,7 @@
 
 	BT_DBG("sock %p, sk %p", sock, sk);
 
-	poll_wait(file, sk->sk_sleep, wait);
+	poll_wait(file, sk_sleep(sk), wait);
 
 	if (sk->sk_state == BT_LISTEN)
 		return bt_accept_poll(sk);
@@ -378,7 +378,7 @@
 
 	BT_DBG("sk %p", sk);
 
-	add_wait_queue(sk->sk_sleep, &wait);
+	add_wait_queue(sk_sleep(sk), &wait);
 	while (sk->sk_state != state) {
 		set_current_state(TASK_INTERRUPTIBLE);
 
@@ -401,7 +401,7 @@
 			break;
 	}
 	set_current_state(TASK_RUNNING);
-	remove_wait_queue(sk->sk_sleep, &wait);
+	remove_wait_queue(sk_sleep(sk), &wait);
 	return err;
 }
 EXPORT_SYMBOL(bt_sock_wait_state);