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/hidp/core.c b/net/bluetooth/hidp/core.c
index 280529a..bfe641b 100644
--- a/net/bluetooth/hidp/core.c
+++ b/net/bluetooth/hidp/core.c
@@ -561,8 +561,8 @@
 
 	init_waitqueue_entry(&ctrl_wait, current);
 	init_waitqueue_entry(&intr_wait, current);
-	add_wait_queue(ctrl_sk->sk_sleep, &ctrl_wait);
-	add_wait_queue(intr_sk->sk_sleep, &intr_wait);
+	add_wait_queue(sk_sleep(ctrl_sk), &ctrl_wait);
+	add_wait_queue(sk_sleep(intr_sk), &intr_wait);
 	while (!atomic_read(&session->terminate)) {
 		set_current_state(TASK_INTERRUPTIBLE);
 
@@ -584,8 +584,8 @@
 		schedule();
 	}
 	set_current_state(TASK_RUNNING);
-	remove_wait_queue(intr_sk->sk_sleep, &intr_wait);
-	remove_wait_queue(ctrl_sk->sk_sleep, &ctrl_wait);
+	remove_wait_queue(sk_sleep(intr_sk), &intr_wait);
+	remove_wait_queue(sk_sleep(ctrl_sk), &ctrl_wait);
 
 	down_write(&hidp_session_sem);
 
@@ -609,7 +609,7 @@
 
 	fput(session->intr_sock->file);
 
-	wait_event_timeout(*(ctrl_sk->sk_sleep),
+	wait_event_timeout(*(sk_sleep(ctrl_sk)),
 		(ctrl_sk->sk_state == BT_CLOSED), msecs_to_jiffies(500));
 
 	fput(session->ctrl_sock->file);