mac80211: refactor the scan code

Move the processing of each scan state into its own functions for better
readability. This patch does not introduce functional changes.
Signed-off-by: Helmut Schaa <helmut.schaa@googlemail.com>
Acked-by: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

net/mac80211/scan.c

@@ -474,51 +474,17 @@ static int __ieee80211_start_scan(struct ieee80211_sub_if_data *sdata,
 	return rc;
 }
 
-void ieee80211_scan_work(struct work_struct *work)
+static int ieee80211_scan_state_set_channel(struct ieee80211_local *local,
+					    unsigned long *next_delay)
 {
-	struct ieee80211_local *local =
-		container_of(work, struct ieee80211_local, scan_work.work);
-	struct ieee80211_sub_if_data *sdata = local->scan_sdata;
+	int skip;
 	struct ieee80211_channel *chan;
-	int skip, i;
-	unsigned long next_delay = 0;
-
-	mutex_lock(&local->scan_mtx);
-	if (!sdata || !local->scan_req) {
-		mutex_unlock(&local->scan_mtx);
-		return;
-	}
-
-	if (local->scan_req && !(local->sw_scanning || local->hw_scanning)) {
-		struct cfg80211_scan_request *req = local->scan_req;
-		int rc;
-
-		local->scan_req = NULL;
-
-		rc = __ieee80211_start_scan(sdata, req);
-		mutex_unlock(&local->scan_mtx);
-
-		if (rc)
-			ieee80211_scan_completed(&local->hw, true);
-		return;
-	}
-
-	mutex_unlock(&local->scan_mtx);
-
-	/*
-	 * Avoid re-scheduling when the sdata is going away.
-	 */
-	if (!netif_running(sdata->dev)) {
-		ieee80211_scan_completed(&local->hw, true);
-		return;
-	}
+	struct ieee80211_sub_if_data *sdata = local->scan_sdata;
 
-	switch (local->scan_state) {
-	case SCAN_SET_CHANNEL:
 	/* if no more bands/channels left, complete scan */
 	if (local->scan_channel_idx >= local->scan_req->n_channels) {
 		ieee80211_scan_completed(&local->hw, false);
-			return;
+		return 1;
 	}
 	skip = 0;
 	chan = local->scan_req->channels[local->scan_channel_idx];
@@ -539,7 +505,7 @@ void ieee80211_scan_work(struct work_struct *work)
 	local->scan_channel_idx++;
 
 	if (skip)
-			break;
+		return 0;
 
 	/*
 	 * Probe delay is used to update the NAV, cf. 11.1.3.2.2
@@ -553,14 +519,22 @@ void ieee80211_scan_work(struct work_struct *work)
 	 */
 	if (chan->flags & IEEE80211_CHAN_PASSIVE_SCAN ||
 	    !local->scan_req->n_ssids) {
-			next_delay = IEEE80211_PASSIVE_CHANNEL_TIME;
-			break;
+		*next_delay = IEEE80211_PASSIVE_CHANNEL_TIME;
+		return 0;
 	}
 
-		next_delay = IEEE80211_PROBE_DELAY;
+	*next_delay = IEEE80211_PROBE_DELAY;
 	local->scan_state = SCAN_SEND_PROBE;
-		break;
-	case SCAN_SEND_PROBE:
+
+	return 0;
+}
+
+static void ieee80211_scan_state_send_probe(struct ieee80211_local *local,
+					    unsigned long *next_delay)
+{
+	int i;
+	struct ieee80211_sub_if_data *sdata = local->scan_sdata;
+
 	for (i = 0; i < local->scan_req->n_ssids; i++)
 		ieee80211_send_probe_req(
 			sdata, NULL,
@@ -572,8 +546,54 @@ void ieee80211_scan_work(struct work_struct *work)
 	 * After sending probe requests, wait for probe responses
 	 * on the channel.
 	 */
-		next_delay = IEEE80211_CHANNEL_TIME;
+	*next_delay = IEEE80211_CHANNEL_TIME;
 	local->scan_state = SCAN_SET_CHANNEL;
+}
+
+void ieee80211_scan_work(struct work_struct *work)
+{
+	struct ieee80211_local *local =
+		container_of(work, struct ieee80211_local, scan_work.work);
+	struct ieee80211_sub_if_data *sdata = local->scan_sdata;
+	unsigned long next_delay = 0;
+
+	mutex_lock(&local->scan_mtx);
+	if (!sdata || !local->scan_req) {
+		mutex_unlock(&local->scan_mtx);
+		return;
+	}
+
+	if (local->scan_req && !(local->sw_scanning || local->hw_scanning)) {
+		struct cfg80211_scan_request *req = local->scan_req;
+		int rc;
+
+		local->scan_req = NULL;
+
+		rc = __ieee80211_start_scan(sdata, req);
+		mutex_unlock(&local->scan_mtx);
+
+		if (rc)
+			ieee80211_scan_completed(&local->hw, true);
+		return;
+	}
+
+	mutex_unlock(&local->scan_mtx);
+
+	/*
+	 * Avoid re-scheduling when the sdata is going away.
+	 */
+	if (!netif_running(sdata->dev)) {
+		ieee80211_scan_completed(&local->hw, true);
+		return;
+	}
+
+	switch (local->scan_state) {
+	case SCAN_SET_CHANNEL:
+		if (ieee80211_scan_state_set_channel(local, &next_delay))
+			return;
+		break;
+	case SCAN_SEND_PROBE:
+		ieee80211_scan_state_send_probe(local, &next_delay);
 		break;
 	}