[PATCH 2/4] Bluetooth: Fix remote and local txWindow roles on L2CAP

["Gustavo F. Padovan" <gustavo@padovan.org>]

L2CAP was misusing the values of txWindow. Now the remote txWindow is used
on the acknowledgement of I-frames and the local txWindow on the sending
of I-frames. It also renames pi->num_to_ack to a better name:
pi->num_acked.

Signed-off-by: Gustavo F. Padovan <gustavo@padovan.org>
---
 include/net/bluetooth/l2cap.h |    5 ++---
 net/bluetooth/l2cap.c         |    9 +++++----
 2 files changed, 7 insertions(+), 7 deletions(-)

diff --git a/include/net/bluetooth/l2cap.h b/include/net/bluetooth/l2cap.h
index c7bf676..f1eca05 100644
--- a/include/net/bluetooth/l2cap.h
+++ b/include/net/bluetooth/l2cap.h
@@ -30,7 +30,6 @@
 #define L2CAP_DEFAULT_MIN_MTU		48
 #define L2CAP_DEFAULT_FLUSH_TO		0xffff
 #define L2CAP_DEFAULT_TX_WINDOW		63
-#define L2CAP_DEFAULT_NUM_TO_ACK        (L2CAP_DEFAULT_TX_WINDOW/5)
 #define L2CAP_DEFAULT_MAX_TX		3
 #define L2CAP_DEFAULT_RETRANS_TO	1000    /* 1 second */
 #define L2CAP_DEFAULT_MONITOR_TO	12000   /* 12 seconds */
@@ -333,7 +332,7 @@ struct l2cap_pinfo {
 	__u8		frames_sent;
 	__u8		unacked_frames;
 	__u8		retry_count;
-	__u8		num_to_ack;
+	__u8		num_acked;
 	__u16		sdu_len;
 	__u16		partial_sdu_len;
 	struct sk_buff	*sdu;
@@ -399,7 +398,7 @@ static inline int l2cap_tx_window_full(struct sock *sk)
 	if (sub < 0)
 		sub += 64;
 
-	return (sub == pi->remote_tx_win);
+	return (sub == pi->tx_win);
 }
 
 #define __get_txseq(ctrl) ((ctrl) & L2CAP_CTRL_TXSEQ) >> 1
diff --git a/net/bluetooth/l2cap.c b/net/bluetooth/l2cap.c
index 6679418..85ec8b2 100644
--- a/net/bluetooth/l2cap.c
+++ b/net/bluetooth/l2cap.c
@@ -2248,7 +2248,7 @@ static inline void l2cap_ertm_init(struct sock *sk)
 	l2cap_pi(sk)->expected_ack_seq = 0;
 	l2cap_pi(sk)->unacked_frames = 0;
 	l2cap_pi(sk)->buffer_seq = 0;
-	l2cap_pi(sk)->num_to_ack = 0;
+	l2cap_pi(sk)->num_acked = 0;
 	l2cap_pi(sk)->frames_sent = 0;
 
 	setup_timer(&l2cap_pi(sk)->retrans_timer,
@@ -2571,7 +2571,7 @@ static int l2cap_parse_conf_rsp(struct sock *sk, void *rsp, int len, void *data,
 	if (*result == L2CAP_CONF_SUCCESS) {
 		switch (rfc.mode) {
 		case L2CAP_MODE_ERTM:
-			pi->remote_tx_win   = rfc.txwin_size;
+			pi->tx_win   = rfc.txwin_size;
 			pi->retrans_timeout = rfc.retrans_timeout;
 			pi->monitor_timeout = rfc.monitor_timeout;
 			pi->max_pdu_size    = le16_to_cpu(rfc.max_pdu_size);
@@ -3408,6 +3408,7 @@ static inline int l2cap_data_channel_iframe(struct sock *sk, u16 rx_control, str
 	u8 tx_seq = __get_txseq(rx_control);
 	u8 req_seq = __get_reqseq(rx_control);
 	u8 sar = rx_control >> L2CAP_CTRL_SAR_SHIFT;
+	int num_to_ack = (pi->remote_tx_win/5) + 1;
 	int err = 0;
 
 	BT_DBG("sk %p rx_control 0x%4.4x len %d", sk, rx_control, skb->len);
@@ -3501,8 +3502,8 @@ expected:
 
 	__mod_ack_timer();
 
-	pi->num_to_ack = (pi->num_to_ack + 1) % L2CAP_DEFAULT_NUM_TO_ACK;
-	if (pi->num_to_ack == L2CAP_DEFAULT_NUM_TO_ACK - 1)
+	pi->num_acked = (pi->num_acked + 1) % num_to_ack;
+	if (pi->num_acked == num_to_ack - 1)
 		l2cap_send_ack(pi);
 
 	return 0;
-- 
1.6.4.4