mwifiex: restart rxreorder timer correctly

During 11n RX reordering, if there is a hole in RX table,
driver will not send packets to kernel until the rxreorder
timer expires or the table is full.
However, currently driver always restarts rxreorder timer when
receiving a packet, which causes the timer hardly to expire.
So while connected with to 11n AP in a busy environment,
ping packets may get blocked for about 30 seconds.

This patch fixes this timer restarting by ensuring rxreorder timer
would only be restarted either timer is not set or start_win
has changed.

Signed-off-by: Chin-Ran Lo <crlo@marvell.com>
Signed-off-by: Plus Chen <pchen@marvell.com>
Signed-off-by: Marc Yang <yangyang@marvell.com>
Signed-off-by: Cathy Luo <cluo@marvell.com>
Signed-off-by: Avinash Patil <patila@marvell.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
diff --git a/drivers/net/wireless/mwifiex/11n_rxreorder.c b/drivers/net/wireless/mwifiex/11n_rxreorder.c
index 4005707..5ef5a0e 100644
--- a/drivers/net/wireless/mwifiex/11n_rxreorder.c
+++ b/drivers/net/wireless/mwifiex/11n_rxreorder.c
@@ -196,6 +196,7 @@
 	mwifiex_11n_dispatch_pkt_until_start_win(priv, tbl, start_win);
 
 	del_timer_sync(&tbl->timer_context.timer);
+	tbl->timer_context.timer_is_set = false;
 
 	spin_lock_irqsave(&priv->rx_reorder_tbl_lock, flags);
 	list_del(&tbl->list);
@@ -297,6 +298,7 @@
 		(struct reorder_tmr_cnxt *) context;
 	int start_win, seq_num;
 
+	ctx->timer_is_set = false;
 	seq_num = mwifiex_11n_find_last_seq_num(ctx);
 
 	if (seq_num < 0)
@@ -385,6 +387,7 @@
 
 	new_node->timer_context.ptr = new_node;
 	new_node->timer_context.priv = priv;
+	new_node->timer_context.timer_is_set = false;
 
 	init_timer(&new_node->timer_context.timer);
 	new_node->timer_context.timer.function = mwifiex_flush_data;
@@ -399,6 +402,22 @@
 	spin_unlock_irqrestore(&priv->rx_reorder_tbl_lock, flags);
 }
 
+static void
+mwifiex_11n_rxreorder_timer_restart(struct mwifiex_rx_reorder_tbl *tbl)
+{
+	u32 min_flush_time;
+
+	if (tbl->win_size >= MWIFIEX_BA_WIN_SIZE_32)
+		min_flush_time = MIN_FLUSH_TIMER_15_MS;
+	else
+		min_flush_time = MIN_FLUSH_TIMER_MS;
+
+	mod_timer(&tbl->timer_context.timer,
+		  jiffies + msecs_to_jiffies(min_flush_time * tbl->win_size));
+
+	tbl->timer_context.timer_is_set = true;
+}
+
 /*
  * This function prepares command for adding a BA request.
  *
@@ -523,31 +542,31 @@
 				u8 *ta, u8 pkt_type, void *payload)
 {
 	struct mwifiex_rx_reorder_tbl *tbl;
-	int start_win, end_win, win_size;
+	int prev_start_win, start_win, end_win, win_size;
 	u16 pkt_index;
 	bool init_window_shift = false;
+	int ret = 0;
 
 	tbl = mwifiex_11n_get_rx_reorder_tbl(priv, tid, ta);
 	if (!tbl) {
 		if (pkt_type != PKT_TYPE_BAR)
 			mwifiex_11n_dispatch_pkt(priv, payload);
-		return 0;
+		return ret;
 	}
 
 	if ((pkt_type == PKT_TYPE_AMSDU) && !tbl->amsdu) {
 		mwifiex_11n_dispatch_pkt(priv, payload);
-		return 0;
+		return ret;
 	}
 
 	start_win = tbl->start_win;
+	prev_start_win = start_win;
 	win_size = tbl->win_size;
 	end_win = ((start_win + win_size) - 1) & (MAX_TID_VALUE - 1);
 	if (tbl->flags & RXREOR_INIT_WINDOW_SHIFT) {
 		init_window_shift = true;
 		tbl->flags &= ~RXREOR_INIT_WINDOW_SHIFT;
 	}
-	mod_timer(&tbl->timer_context.timer,
-		  jiffies + msecs_to_jiffies(MIN_FLUSH_TIMER_MS * win_size));
 
 	if (tbl->flags & RXREOR_FORCE_NO_DROP) {
 		dev_dbg(priv->adapter->dev,
@@ -568,11 +587,14 @@
 		if ((start_win + TWOPOW11) > (MAX_TID_VALUE - 1)) {
 			if (seq_num >= ((start_win + TWOPOW11) &
 					(MAX_TID_VALUE - 1)) &&
-			    seq_num < start_win)
-				return -1;
+			    seq_num < start_win) {
+				ret = -1;
+				goto done;
+			}
 		} else if ((seq_num < start_win) ||
-			   (seq_num > (start_win + TWOPOW11))) {
-			return -1;
+			   (seq_num >= (start_win + TWOPOW11))) {
+			ret = -1;
+			goto done;
 		}
 	}
 
@@ -601,8 +623,10 @@
 		else
 			pkt_index = (seq_num+MAX_TID_VALUE) - start_win;
 
-		if (tbl->rx_reorder_ptr[pkt_index])
-			return -1;
+		if (tbl->rx_reorder_ptr[pkt_index]) {
+			ret = -1;
+			goto done;
+		}
 
 		tbl->rx_reorder_ptr[pkt_index] = payload;
 	}
@@ -613,7 +637,11 @@
 	 */
 	mwifiex_11n_scan_and_dispatch(priv, tbl);
 
-	return 0;
+done:
+	if (!tbl->timer_context.timer_is_set ||
+	    prev_start_win != tbl->start_win)
+		mwifiex_11n_rxreorder_timer_restart(tbl);
+	return ret;
 }
 
 /*
diff --git a/drivers/net/wireless/mwifiex/11n_rxreorder.h b/drivers/net/wireless/mwifiex/11n_rxreorder.h
index 3a87bb0..63ecea8 100644
--- a/drivers/net/wireless/mwifiex/11n_rxreorder.h
+++ b/drivers/net/wireless/mwifiex/11n_rxreorder.h
@@ -21,6 +21,8 @@
 #define _MWIFIEX_11N_RXREORDER_H_
 
 #define MIN_FLUSH_TIMER_MS		50
+#define MIN_FLUSH_TIMER_15_MS		15
+#define MWIFIEX_BA_WIN_SIZE_32		32
 
 #define PKT_TYPE_BAR 0xE7
 #define MAX_TID_VALUE			(2 << 11)
diff --git a/drivers/net/wireless/mwifiex/main.h b/drivers/net/wireless/mwifiex/main.h
index e263574..f55658d 100644
--- a/drivers/net/wireless/mwifiex/main.h
+++ b/drivers/net/wireless/mwifiex/main.h
@@ -592,6 +592,7 @@
 	struct timer_list timer;
 	struct mwifiex_rx_reorder_tbl *ptr;
 	struct mwifiex_private *priv;
+	u8 timer_is_set;
 };
 
 struct mwifiex_rx_reorder_tbl {