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>

diff --git a/net/mac80211/scan.c b/net/mac80211/scan.c
index 7482065..71500f1 100644 (file)
--- a/net/mac80211/scan.c
+++ b/net/mac80211/scan.c
@@ -474,13 +474,87 @@ static int __ieee80211_start_scan(struct ieee80211_sub_if_data *sdata,
        return rc;
 }
 
+static int ieee80211_scan_state_set_channel(struct ieee80211_local *local,
+                                           unsigned long *next_delay)
+{
+       int skip;
+       struct ieee80211_channel *chan;
+       struct ieee80211_sub_if_data *sdata = local->scan_sdata;
+
+       /* 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 1;
+       }
+       skip = 0;
+       chan = local->scan_req->channels[local->scan_channel_idx];
+
+       if (chan->flags & IEEE80211_CHAN_DISABLED ||
+           (sdata->vif.type == NL80211_IFTYPE_ADHOC &&
+            chan->flags & IEEE80211_CHAN_NO_IBSS))
+               skip = 1;
+
+       if (!skip) {
+               local->scan_channel = chan;
+               if (ieee80211_hw_config(local,
+                                       IEEE80211_CONF_CHANGE_CHANNEL))
+                       skip = 1;
+       }
+
+       /* advance state machine to next channel/band */
+       local->scan_channel_idx++;
+
+       if (skip)
+               return 0;
+
+       /*
+        * Probe delay is used to update the NAV, cf. 11.1.3.2.2
+        * (which unfortunately doesn't say _why_ step a) is done,
+        * but it waits for the probe delay or until a frame is
+        * received - and the received frame would update the NAV).
+        * For now, we do not support waiting until a frame is
+        * received.
+        *
+        * In any case, it is not necessary for a passive scan.
+        */
+       if (chan->flags & IEEE80211_CHAN_PASSIVE_SCAN ||
+           !local->scan_req->n_ssids) {
+               *next_delay = IEEE80211_PASSIVE_CHANNEL_TIME;
+               return 0;
+       }
+
+       *next_delay = IEEE80211_PROBE_DELAY;
+       local->scan_state = 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,
+                       local->scan_req->ssids[i].ssid,
+                       local->scan_req->ssids[i].ssid_len,
+                       local->scan_req->ie, local->scan_req->ie_len);
+
+       /*
+        * After sending probe requests, wait for probe responses
+        * on the channel.
+        */
+       *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;
-       struct ieee80211_channel *chan;
-       int skip, i;
        unsigned long next_delay = 0;
 
        mutex_lock(&local->scan_mtx);
@@ -515,65 +589,11 @@ void ieee80211_scan_work(struct work_struct *work)
 
        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);
+               if (ieee80211_scan_state_set_channel(local, &next_delay))
                        return;
-               }
-               skip = 0;
-               chan = local->scan_req->channels[local->scan_channel_idx];
-
-               if (chan->flags & IEEE80211_CHAN_DISABLED ||
-                   (sdata->vif.type == NL80211_IFTYPE_ADHOC &&
-                    chan->flags & IEEE80211_CHAN_NO_IBSS))
-                       skip = 1;
-
-               if (!skip) {
-                       local->scan_channel = chan;
-                       if (ieee80211_hw_config(local,
-                                               IEEE80211_CONF_CHANGE_CHANNEL))
-                               skip = 1;
-               }
-
-               /* advance state machine to next channel/band */
-               local->scan_channel_idx++;
-
-               if (skip)
-                       break;
-
-               /*
-                * Probe delay is used to update the NAV, cf. 11.1.3.2.2
-                * (which unfortunately doesn't say _why_ step a) is done,
-                * but it waits for the probe delay or until a frame is
-                * received - and the received frame would update the NAV).
-                * For now, we do not support waiting until a frame is
-                * received.
-                *
-                * In any case, it is not necessary for a passive scan.
-                */
-               if (chan->flags & IEEE80211_CHAN_PASSIVE_SCAN ||
-                   !local->scan_req->n_ssids) {
-                       next_delay = IEEE80211_PASSIVE_CHANNEL_TIME;
-                       break;
-               }
-
-               next_delay = IEEE80211_PROBE_DELAY;
-               local->scan_state = SCAN_SEND_PROBE;
                break;
        case SCAN_SEND_PROBE:
-               for (i = 0; i < local->scan_req->n_ssids; i++)
-                       ieee80211_send_probe_req(
-                               sdata, NULL,
-                               local->scan_req->ssids[i].ssid,
-                               local->scan_req->ssids[i].ssid_len,
-                               local->scan_req->ie, local->scan_req->ie_len);
-
-               /*
-                * After sending probe requests, wait for probe responses
-                * on the channel.
-                */
-               next_delay = IEEE80211_CHANNEL_TIME;
-               local->scan_state = SCAN_SET_CHANNEL;
+               ieee80211_scan_state_send_probe(local, &next_delay);
                break;
        }