This patch aims to decrease channel switching when there is at least one
interface associated. This should help multiple station interfaces co-exist
on the same hardware, especially in WPA mode.
This patch is on top of the other 3 I posted recently, and even though I think
this patch is going in the right direction, I still cannot get two WPA interfaces
to complete authentication.
Thanks,
Ben
--
Ben Greear <greearb@xxxxxxxxxxxxxxx>
Candela Technologies Inc http://www.candelatech.com
diff --git a/drivers/net/wireless/ath/ath9k/main.c b/drivers/net/wireless/ath/ath9k/main.c
index 1165f90..13673bb 100644
--- a/drivers/net/wireless/ath/ath9k/main.c
+++ b/drivers/net/wireless/ath/ath9k/main.c
@@ -1605,7 +1605,12 @@ static int ath9k_config(struct ieee80211_hw *hw, u32 changed)
struct ieee80211_channel *curchan = hw->conf.channel;
int pos = curchan->hw_value;
+ /* If channels are the same, then don't actually do anything.
+ */
+ if (sc->sc_ah->curchan == &sc->sc_ah->channels[pos])
+ goto skip_chan_change;
+
aphy->chan_idx = pos;
aphy->chan_is_ht = conf_is_ht(conf);
if (hw->conf.flags & IEEE80211_CONF_OFFCHANNEL)
diff --git a/net/mac80211/ieee80211_i.h b/net/mac80211/ieee80211_i.h
index 4e635e2..631b094 100644
--- a/net/mac80211/ieee80211_i.h
+++ b/net/mac80211/ieee80211_i.h
@@ -790,6 +790,8 @@ struct ieee80211_local {
enum ieee80211_band hw_scan_band;
int scan_channel_idx;
int scan_ies_len;
+ int scanned_count; /* how many channels scanned so far in this scan */
+ bool scan_probe_once; /* if true, scan only the current channel. */
unsigned long leave_oper_channel_time;
enum mac80211_scan_state next_scan_state;
diff --git a/net/mac80211/mlme.c b/net/mac80211/mlme.c
index 0cb822c..abb76ae 100644
--- a/net/mac80211/mlme.c
+++ b/net/mac80211/mlme.c
@@ -1845,10 +1845,11 @@ void ieee80211_sta_work(struct ieee80211_sub_if_data *sdata)
else if (ifmgd->probe_send_count < IEEE80211_MAX_PROBE_TRIES) {
#ifdef CONFIG_MAC80211_VERBOSE_DEBUG
- printk(KERN_DEBUG "No probe response from AP %pM"
- " after %dms, try %d\n", bssid,
+ printk(KERN_DEBUG "%s: No probe response from AP %pM"
+ " after %dms, try %d flags: 0x%x\n",
+ sdata->dev->name, bssid,
(1000 * IEEE80211_PROBE_WAIT)/HZ,
- ifmgd->probe_send_count);
+ ifmgd->probe_send_count, ifmgd->flags);
#endif
ieee80211_mgd_probe_ap_send(sdata);
} else {
@@ -1858,9 +1859,10 @@ void ieee80211_sta_work(struct ieee80211_sub_if_data *sdata)
*/
ifmgd->flags &= ~(IEEE80211_STA_CONNECTION_POLL |
IEEE80211_STA_BEACON_POLL);
- printk(KERN_DEBUG "No probe response from AP %pM"
- " after %dms, disconnecting.\n",
- bssid, (1000 * IEEE80211_PROBE_WAIT)/HZ);
+ printk(KERN_DEBUG "%s: No probe response from AP %pM"
+ " after %dms, disconnecting, flags: 0x%x\n",
+ sdata->dev->name, bssid,
+ (1000 * IEEE80211_PROBE_WAIT)/HZ, ifmgd->flags);
ieee80211_set_disassoc(sdata, true);
mutex_unlock(&ifmgd->mtx);
mutex_lock(&local->mtx);
diff --git a/net/mac80211/rx.c b/net/mac80211/rx.c
index ac205a3..e8ea84d 100644
--- a/net/mac80211/rx.c
+++ b/net/mac80211/rx.c
@@ -2399,7 +2399,7 @@ static void ieee80211_rx_handlers(struct ieee80211_rx_data *rx,
do { \
res = rxh(rx); \
if (res != RX_CONTINUE) \
- goto rxh_next; \
+ goto rxh_next; \
} while (0);
while ((skb = __skb_dequeue(frames))) {
diff --git a/net/mac80211/scan.c b/net/mac80211/scan.c
index e20fb52..1c9f0a8 100644
--- a/net/mac80211/scan.c
+++ b/net/mac80211/scan.c
@@ -292,7 +292,9 @@ static void __ieee80211_scan_completed(struct ieee80211_hw *hw, bool aborted)
/* we only have to protect scan_req and hw/sw scan */
mutex_unlock(&local->mtx);
- ieee80211_hw_config(local, IEEE80211_CONF_CHANGE_CHANNEL);
+ if (!local->scan_probe_once)
+ ieee80211_hw_config(local, IEEE80211_CONF_CHANGE_CHANNEL);
+
if (was_hw_scan)
goto done;
@@ -300,7 +302,8 @@ static void __ieee80211_scan_completed(struct ieee80211_hw *hw, bool aborted)
drv_sw_scan_complete(local);
- ieee80211_offchannel_return(local, true);
+ if (!local->scan_probe_once)
+ ieee80211_offchannel_return(local, true);
done:
mutex_lock(&local->mtx);
@@ -340,13 +343,43 @@ static int ieee80211_start_sw_scan(struct ieee80211_local *local)
* nullfunc frames and probe requests will be dropped in
* ieee80211_tx_h_check_assoc().
*/
- drv_sw_scan_start(local);
+ int avifs = 0;
+ int svifs = 0;
+ struct ieee80211_sub_if_data *sdata;
+
+ mutex_lock(&local->iflist_mtx);
+ list_for_each_entry(sdata, &local->interfaces, list) {
+ if (!ieee80211_sdata_running(sdata))
+ continue;
- ieee80211_offchannel_stop_beaconing(local);
+ if (sdata->vif.type != NL80211_IFTYPE_STATION
+ || sdata->u.mgd.associated)
+ avifs++;
- local->leave_oper_channel_time = 0;
+ if (sdata->vif.type == NL80211_IFTYPE_STATION)
+ svifs++;
+ }
+ mutex_unlock(&local->iflist_mtx);
+
+ /* If one sta is associated, we don't want another to start scanning,
+ * as that will un-associate the first.
+ * TODO: This still leaves a race when a thundering herd of WPA
+ * supplicants are all coming up at once.
+ */
+ if ((avifs > 1) || ((avifs == 1) && (svifs > 1)))
+ local->scan_probe_once = true;
+ else
+ local->scan_probe_once = false;
+
+ drv_sw_scan_start(local);
+
+ if (!local->scan_probe_once) {
+ ieee80211_offchannel_stop_beaconing(local);
+ local->leave_oper_channel_time = 0;
+ local->scan_channel_idx = 0;
+ }
+ local->scanned_count = 0;
local->next_scan_state = SCAN_DECISION;
- local->scan_channel_idx = 0;
drv_flush(local, false);
@@ -459,7 +492,8 @@ static int ieee80211_scan_state_decision(struct ieee80211_local *local,
struct ieee80211_channel *next_chan;
/* if no more bands/channels left, complete scan and advance to the idle state */
- if (local->scan_channel_idx >= local->scan_req->n_channels) {
+ if ((local->scan_channel_idx >= local->scan_req->n_channels) ||
+ (local->scanned_count && local->scan_probe_once)) {
__ieee80211_scan_completed(&local->hw, false);
return 1;
}
@@ -528,10 +562,13 @@ static int ieee80211_scan_state_decision(struct ieee80211_local *local,
local->next_scan_state = SCAN_SET_CHANNEL;
} else {
/*
- * we're on the operating channel currently, let's
- * leave that channel now to scan another one
+ * we're on the operating channel currently, Leave that
+ * channel if we are not probing the single channel.
*/
- local->next_scan_state = SCAN_LEAVE_OPER_CHANNEL;
+ if (local->scan_probe_once)
+ local->next_scan_state = SCAN_SET_CHANNEL;
+ else
+ local->next_scan_state = SCAN_LEAVE_OPER_CHANNEL;
}
*next_delay = 0;
@@ -566,14 +603,15 @@ static void ieee80211_scan_state_enter_oper_channel(struct ieee80211_local *loca
{
/* switch back to the operating channel */
local->scan_channel = NULL;
- ieee80211_hw_config(local, IEEE80211_CONF_CHANGE_CHANNEL);
-
- /*
- * Only re-enable station mode interface now; beaconing will be
- * re-enabled once the full scan has been completed.
- */
- ieee80211_offchannel_return(local, false);
+ if (!local->scan_probe_once) {
+ ieee80211_hw_config(local, IEEE80211_CONF_CHANGE_CHANNEL);
+ /*
+ * Only re-enable station mode interface now; beaconing will be
+ * re-enabled once the full scan has been completed.
+ */
+ ieee80211_offchannel_return(local, false);
+ }
__clear_bit(SCAN_OFF_CHANNEL, &local->scanning);
*next_delay = HZ / 5;
@@ -587,19 +625,25 @@ static void ieee80211_scan_state_set_channel(struct ieee80211_local *local,
struct ieee80211_channel *chan;
skip = 0;
- chan = local->scan_req->channels[local->scan_channel_idx];
+ if (local->scan_probe_once) {
+ chan = local->oper_channel;
+ local->scan_channel = chan;
+ } else {
+ chan = local->scan_req->channels[local->scan_channel_idx];
+ local->scan_channel = chan;
- local->scan_channel = chan;
- if (ieee80211_hw_config(local, IEEE80211_CONF_CHANGE_CHANNEL))
- skip = 1;
+ if (ieee80211_hw_config(local, IEEE80211_CONF_CHANGE_CHANNEL))
+ skip = 1;
- /* advance state machine to next channel/band */
- local->scan_channel_idx++;
+ /* advance state machine to next channel/band */
+ local->scan_channel_idx++;
- if (skip) {
- /* if we skip this channel return to the decision state */
- local->next_scan_state = SCAN_DECISION;
- return;
+ if (skip) {
+ /* if we skip this channel return to the decision
+ * state */
+ local->next_scan_state = SCAN_DECISION;
+ return;
+ }
}
/*
@@ -615,6 +659,7 @@ static void ieee80211_scan_state_set_channel(struct ieee80211_local *local,
if (chan->flags & IEEE80211_CHAN_PASSIVE_SCAN ||
!local->scan_req->n_ssids) {
*next_delay = IEEE80211_PASSIVE_CHANNEL_TIME;
+ local->scanned_count++;
local->next_scan_state = SCAN_DECISION;
return;
}
@@ -637,6 +682,7 @@ static void ieee80211_scan_state_send_probe(struct ieee80211_local *local,
local->scan_req->ssids[i].ssid_len,
local->scan_req->ie, local->scan_req->ie_len);
+ local->scanned_count++;
/*
* After sending probe requests, wait for probe responses
* on the channel.
diff --git a/net/mac80211/work.c b/net/mac80211/work.c
index ae344d1..1bfc1e0 100644
--- a/net/mac80211/work.c
+++ b/net/mac80211/work.c
@@ -910,12 +910,17 @@ static void ieee80211_work_work(struct work_struct *work)
* happen to be on the same channel as
* the requested channel
*/
- ieee80211_offchannel_stop_beaconing(local);
- ieee80211_offchannel_stop_station(local);
-
- local->tmp_channel = wk->chan;
- local->tmp_channel_type = wk->chan_type;
- ieee80211_hw_config(local, 0);
+ if (!(wk->chan == local->scan_channel ||
+ (wk->chan == local->oper_channel &&
+ !local->scan_channel))) {
+ /* Only change channels if we need to */
+ ieee80211_offchannel_stop_beaconing(local);
+ ieee80211_offchannel_stop_station(local);
+
+ local->tmp_channel = wk->chan;
+ local->tmp_channel_type = wk->chan_type;
+ ieee80211_hw_config(local, 0);
+ }
started = true;
wk->timeout = jiffies;
}
