From 7d3be3cc489176bc7bd23e673b0b4aef597af2b3 Mon Sep 17 00:00:00 2001 From: Helmut Schaa Date: Thu, 23 Jul 2009 12:13:41 +0200 Subject: [PATCH] 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 Acked-by: Johannes Berg Signed-off-by: John W. Linville --- net/mac80211/scan.c | 136 +++++++++++++++++++++++++------------------- 1 file 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; } -- 2.39.5