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>

1 files changed, 78 insertions, 58 deletions

diff --git a/net/mac80211/scan.c b/net/mac80211/scan.c
index 74820656dc89..71500f1dddbc 100644
--- 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;
         }