mwifiex: use separate wait condition for each command node

Currently global wait condition (adapter->cmd_wait_q.condition)
is used while sending synchronous commands to FW. When two threads
enter in mwifiex_send_cmd_sync() routine at the same time, both the
threads wait for their command responses. Since wait condition is
same for both, they wake up simultaneously after getting response
of 1st command. After this when a thread is waiting for command
response of 3rd command, it wakes up after getting response of 2nd
command and so on. Therefore we don't wait for the response of last
command(0xaa) during unload. Hence while next time loading the driver
command time out is seen for INIT command.

This problem is resolved by having separate wait condition flag for
each command(except scan command). Since scan command is treated
differently (by maintaining scan pending q etc.), newly defined flag
(scan_wait_q_woken) is used as a scan wait condition.

Signed-off-by: Amitkumar Karwar <[e-mail]>
Signed-off-by: Yogesh Ashok Powar <[e-mail]>
Signed-off-by: Bing Zhao <[e-mail]>
Signed-off-by: John W. Linville <[e-mail]>

drivers/net/wireless/mwifiex/cmdevt.c

···
 {
 	cmd_node->priv = priv;
 	cmd_node->cmd_oid = cmd_oid;
-	cmd_node->wait_q_enabled = priv->adapter->cmd_wait_q_required;
-	priv->adapter->cmd_wait_q_required = false;
+	if (priv->adapter->cmd_wait_q_required) {
+		cmd_node->wait_q_enabled = priv->adapter->cmd_wait_q_required;
+		priv->adapter->cmd_wait_q_required = false;
+		cmd_node->cmd_wait_q_woken = false;
+		cmd_node->condition = &cmd_node->cmd_wait_q_woken;
+	}
 	cmd_node->data_buf = data_buf;
 	cmd_node->cmd_skb = cmd_node->skb;
 }
···
 	struct mwifiex_adapter *adapter = priv->adapter;
 
 	adapter->cmd_wait_q_required = true;
-	adapter->cmd_wait_q.condition = false;
 
 	ret = mwifiex_send_cmd_async(priv, cmd_no, cmd_action, cmd_oid,
 				     data_buf);
···
 	}
 
 	/* Send command */
-	if (cmd_no == HostCmd_CMD_802_11_SCAN)
+	if (cmd_no == HostCmd_CMD_802_11_SCAN) {
 		mwifiex_queue_scan_cmd(priv, cmd_node);
-	else
+	} else {
+		adapter->cmd_queued = cmd_node;
 		mwifiex_insert_cmd_to_pending_q(adapter, cmd_node, true);
+	}
 
 	return ret;
 }
···
 		return;
 
 	if (cmd_node->wait_q_enabled)
-		mwifiex_complete_cmd(adapter);
+		mwifiex_complete_cmd(adapter, cmd_node);
 	/* Clean the node */
 	mwifiex_clean_cmd_node(adapter, cmd_node);
 
···
 		adapter->curr_cmd->wait_q_enabled = false;
 		spin_unlock_irqrestore(&adapter->mwifiex_cmd_lock, flags);
 		adapter->cmd_wait_q.status = -1;
-		mwifiex_complete_cmd(adapter);
+		mwifiex_complete_cmd(adapter, adapter->curr_cmd);
 	}
 	/* Cancel all pending command */
 	spin_lock_irqsave(&adapter->cmd_pending_q_lock, flags);
···
 
 		if (cmd_node->wait_q_enabled) {
 			adapter->cmd_wait_q.status = -1;
-			mwifiex_complete_cmd(adapter);
+			mwifiex_complete_cmd(adapter, cmd_node);
 			cmd_node->wait_q_enabled = false;
 		}
 		mwifiex_insert_cmd_to_free_q(adapter, cmd_node);
···
 		spin_unlock_irqrestore(&adapter->mwifiex_cmd_lock, cmd_flags);
 	}
 	adapter->cmd_wait_q.status = -1;
-	mwifiex_complete_cmd(adapter);
+	mwifiex_complete_cmd(adapter, adapter->curr_cmd);
 }
 
 /*

drivers/net/wireless/mwifiex/decl.h

···
 
 struct mwifiex_wait_queue {
 	wait_queue_head_t wait;
-	u16 condition;
 	int status;
 };
 

drivers/net/wireless/mwifiex/main.c

···
 	init_waitqueue_head(&adapter->hs_activate_wait_q);
 	adapter->cmd_wait_q_required = false;
 	init_waitqueue_head(&adapter->cmd_wait_q.wait);
-	adapter->cmd_wait_q.condition = false;
 	adapter->cmd_wait_q.status = 0;
+	adapter->scan_wait_q_woken = false;
 
 	adapter->workqueue = create_workqueue("MWIFIEX_WORK_QUEUE");
 	if (!adapter->workqueue)

drivers/net/wireless/mwifiex/main.h

···
 	void *data_buf;
 	u32 wait_q_enabled;
 	struct sk_buff *skb;
+	u8 *condition;
+	u8 cmd_wait_q_woken;
 };
 
 struct mwifiex_if_ops {
···
 	u32 arp_filter_size;
 	u16 cmd_wait_q_required;
 	struct mwifiex_wait_queue cmd_wait_q;
+	u8 scan_wait_q_woken;
+	struct cmd_ctrl_node *cmd_queued;
 };
 
 int mwifiex_init_lock_list(struct mwifiex_adapter *adapter);
···
 
 int mwifiex_process_event(struct mwifiex_adapter *adapter);
 
-int mwifiex_complete_cmd(struct mwifiex_adapter *adapter);
+int mwifiex_complete_cmd(struct mwifiex_adapter *adapter,
+			 struct cmd_ctrl_node *cmd_node);
 
 int mwifiex_send_cmd_async(struct mwifiex_private *priv, uint16_t cmd_no,
 			   u16 cmd_action, u32 cmd_oid, void *data_buf);

drivers/net/wireless/mwifiex/scan.c

···
 {
 	int status;
 
-	priv->adapter->cmd_wait_q.condition = false;
+	priv->adapter->scan_wait_q_woken = false;
 
 	status = mwifiex_scan_networks(priv, scan_req);
 	if (!status)
···
 			list_del(&cmd_node->list);
 			spin_unlock_irqrestore(&adapter->scan_pending_q_lock,
 									flags);
+			adapter->cmd_queued = cmd_node;
 			mwifiex_insert_cmd_to_pending_q(adapter, cmd_node,
 							true);
 		} else {
···
 		/* Need to indicate IOCTL complete */
 		if (adapter->curr_cmd->wait_q_enabled) {
 			adapter->cmd_wait_q.status = 0;
-			mwifiex_complete_cmd(adapter);
+			mwifiex_complete_cmd(adapter, adapter->curr_cmd);
 		}
 		if (priv->report_scan_result)
 			priv->report_scan_result = false;
···
 	unsigned long flags;
 
 	cmd_node->wait_q_enabled = true;
+	cmd_node->condition = &adapter->scan_wait_q_woken;
 	spin_lock_irqsave(&adapter->scan_pending_q_lock, flags);
 	list_add_tail(&cmd_node->list, &adapter->scan_pending_q);
 	spin_unlock_irqrestore(&adapter->scan_pending_q_lock, flags);
···
 	}
 	priv->scan_pending_on_block = true;
 
-	priv->adapter->cmd_wait_q.condition = false;
+	priv->adapter->scan_wait_q_woken = false;
 
 	if (req_ssid && req_ssid->ssid_len != 0)
 		/* Specific SSID scan */

drivers/net/wireless/mwifiex/sta_ioctl.c

···
 {
 	bool cancel_flag = false;
 	int status = adapter->cmd_wait_q.status;
+	struct cmd_ctrl_node *cmd_queued = adapter->cmd_queued;
 
+	adapter->cmd_queued = NULL;
 	dev_dbg(adapter->dev, "cmd pending\n");
 	atomic_inc(&adapter->cmd_pending);
 
···
 
 	/* Wait for completion */
 	wait_event_interruptible(adapter->cmd_wait_q.wait,
-					adapter->cmd_wait_q.condition);
-	if (!adapter->cmd_wait_q.condition)
+					*(cmd_queued->condition));
+	if (!*(cmd_queued->condition))
 		cancel_flag = true;
 
 	if (cancel_flag) {

drivers/net/wireless/mwifiex/util.c

···
  * corresponding waiting function. Otherwise, it processes the
  * IOCTL response and frees the response buffer.
  */
-int mwifiex_complete_cmd(struct mwifiex_adapter *adapter)
+int mwifiex_complete_cmd(struct mwifiex_adapter *adapter,
+			 struct cmd_ctrl_node *cmd_node)
 {
 	atomic_dec(&adapter->cmd_pending);
 	dev_dbg(adapter->dev, "cmd completed: status=%d\n",
 					adapter->cmd_wait_q.status);
 
-	adapter->cmd_wait_q.condition = true;
+	*(cmd_node->condition) = true;
 
 	if (adapter->cmd_wait_q.status == -ETIMEDOUT)
 		dev_err(adapter->dev, "cmd timeout\n");