Bluetooth: Move code for ERTM local busy state to separate functions

The local busy state is entered and exited based on buffer status in
the socket layer (or other upper layer).  This change is in
preparation for general buffer status reports from the socket layer,
which will then be used to change the local busy status.
Signed-off-by: Mat Martineau <mathewm@codeaurora.org>
Signed-off-by: Gustavo F. Padovan <padovan@profusion.mobi>

net/bluetooth/l2cap_core.c

@@ -3227,22 +3227,26 @@ static int l2cap_ertm_reassembly_sdu(struct l2cap_chan *chan, struct sk_buff *sk
 	return 0;
 }
 
-static int l2cap_try_push_rx_skb(struct l2cap_chan *chan)
+static void l2cap_ertm_enter_local_busy(struct l2cap_chan *chan)
 {
-	struct sk_buff *skb;
 	u16 control;
-	int err;
 
-	while ((skb = skb_dequeue(&chan->busy_q))) {
-		control = bt_cb(skb)->sar << L2CAP_CTRL_SAR_SHIFT;
-		err = l2cap_ertm_reassembly_sdu(chan, skb, control);
-		if (err < 0) {
-			skb_queue_head(&chan->busy_q, skb);
-			return -EBUSY;
-		}
+	BT_DBG("chan %p, Enter local busy", chan);
 
-		chan->buffer_seq = (chan->buffer_seq + 1) % 64;
-	}
+	set_bit(CONN_LOCAL_BUSY, &chan->conn_state);
+
+	control = chan->buffer_seq << L2CAP_CTRL_REQSEQ_SHIFT;
+	control |= L2CAP_SUPER_RCV_NOT_READY;
+	l2cap_send_sframe(chan, control);
+
+	set_bit(CONN_RNR_SENT, &chan->conn_state);
+
+	__clear_ack_timer(chan);
+}
+
+static void l2cap_ertm_exit_local_busy(struct l2cap_chan *chan)
+{
+	u16 control;
 
 	if (!test_bit(CONN_RNR_SENT, &chan->conn_state))
 		goto done;
@@ -3262,6 +3266,26 @@ static int l2cap_try_push_rx_skb(struct l2cap_chan *chan)
 	clear_bit(CONN_RNR_SENT, &chan->conn_state);
 
 	BT_DBG("chan %p, Exit local busy", chan);
+}
+
+static int l2cap_try_push_rx_skb(struct l2cap_chan *chan)
+{
+	struct sk_buff *skb;
+	u16 control;
+	int err;
+
+	while ((skb = skb_dequeue(&chan->busy_q))) {
+		control = bt_cb(skb)->sar << L2CAP_CTRL_SAR_SHIFT;
+		err = l2cap_ertm_reassembly_sdu(chan, skb, control);
+		if (err < 0) {
+			skb_queue_head(&chan->busy_q, skb);
+			return -EBUSY;
+		}
+
+		chan->buffer_seq = (chan->buffer_seq + 1) % 64;
+	}
+
+	l2cap_ertm_exit_local_busy(chan);
 
 	return 0;
 }
@@ -3315,7 +3339,7 @@ static void l2cap_busy_work(struct work_struct *work)
 
 static int l2cap_push_rx_skb(struct l2cap_chan *chan, struct sk_buff *skb, u16 control)
 {
-	int sctrl, err;
+	int err;
 
 	if (test_bit(CONN_LOCAL_BUSY, &chan->conn_state)) {
 		bt_cb(skb)->sar = control >> L2CAP_CTRL_SAR_SHIFT;
@@ -3331,21 +3355,11 @@ static int l2cap_push_rx_skb(struct l2cap_chan *chan, struct sk_buff *skb, u16 c
 		return err;
 	}
 
-	/* Busy Condition */
-	BT_DBG("chan %p, Enter local busy", chan);
+	l2cap_ertm_enter_local_busy(chan);
 
-	set_bit(CONN_LOCAL_BUSY, &chan->conn_state);
 	bt_cb(skb)->sar = control >> L2CAP_CTRL_SAR_SHIFT;
 	__skb_queue_tail(&chan->busy_q, skb);
 
-	sctrl = chan->buffer_seq << L2CAP_CTRL_REQSEQ_SHIFT;
-	sctrl |= L2CAP_SUPER_RCV_NOT_READY;
-	l2cap_send_sframe(chan, sctrl);
-
-	set_bit(CONN_RNR_SENT, &chan->conn_state);
-
-	__clear_ack_timer(chan);
-
 	queue_work(_busy_wq, &chan->busy_work);
 
 	return err;