From: Ben Greear <greearb@xxxxxxxxxxxxxxx>
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.
Signed-off-by: Ben Greear <greearb@xxxxxxxxxxxxxxx>
---
:100644 100644 f0518b0... 7ecf8b0... M include/linux/nl80211.h
:100644 100644 a0613ff... f355b8c... M include/net/cfg80211.h
:100644 100644 945fbf2... ac720d2... M net/mac80211/ieee80211_i.h
:100644 100644 8b733cf... 6323954... M net/mac80211/mlme.c
:100644 100644 0b0e83e... 318b2de... M net/mac80211/rx.c
:100644 100644 57b5e66... 59d5925... M net/mac80211/scan.c
:100644 100644 ae344d1... 1bfc1e0... M net/mac80211/work.c
:100644 100644 4ff827e... b45646e... M net/wireless/nl80211.c
:100644 100644 f161b98... 87b0cd7... M net/wireless/sme.c
include/linux/nl80211.h | 2 +
include/net/cfg80211.h | 3 +
net/mac80211/ieee80211_i.h | 2 +
net/mac80211/mlme.c | 14 +++--
net/mac80211/rx.c | 2 +-
net/mac80211/scan.c | 110 +++++++++++++++++++++++++++++++++-----------
net/mac80211/work.c | 17 ++++--
net/wireless/nl80211.c | 6 ++
net/wireless/sme.c | 5 ++
9 files changed, 121 insertions(+), 40 deletions(-)
diff --git a/include/linux/nl80211.h b/include/linux/nl80211.h
index f0518b0..7ecf8b0 100644
--- a/include/linux/nl80211.h
+++ b/include/linux/nl80211.h
@@ -965,6 +965,8 @@ enum nl80211_attrs {
NL80211_ATTR_CONTROL_PORT_ETHERTYPE,
NL80211_ATTR_CONTROL_PORT_NO_ENCRYPT,
+ NL80211_ATTR_SCAN_ONE_IF_ASSOC,
+
/* add attributes here, update the policy in nl80211.c */
__NL80211_ATTR_AFTER_LAST,
diff --git a/include/net/cfg80211.h b/include/net/cfg80211.h
index a0613ff..f355b8c 100644
--- a/include/net/cfg80211.h
+++ b/include/net/cfg80211.h
@@ -667,6 +667,8 @@ struct cfg80211_ssid {
* @wiphy: the wiphy this was for
* @dev: the interface
* @aborted: (internal) scan request was notified as aborted
+ * @can_scan_one: If true, only scan active channel if at least one
+ * vif is already associated.
*/
struct cfg80211_scan_request {
struct cfg80211_ssid *ssids;
@@ -679,6 +681,7 @@ struct cfg80211_scan_request {
struct wiphy *wiphy;
struct net_device *dev;
bool aborted;
+ bool can_scan_one;
/* keep last */
struct ieee80211_channel *channels[0];
diff --git a/net/mac80211/ieee80211_i.h b/net/mac80211/ieee80211_i.h
index 945fbf2..ac720d2 100644
--- a/net/mac80211/ieee80211_i.h
+++ b/net/mac80211/ieee80211_i.h
@@ -815,6 +815,8 @@ 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 8b733cf..6323954 100644
--- a/net/mac80211/mlme.c
+++ b/net/mac80211/mlme.c
@@ -1863,10 +1863,11 @@ 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 {
@@ -1876,9 +1877,10 @@ 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 0b0e83e..318b2de 100644
--- a/net/mac80211/rx.c
+++ b/net/mac80211/rx.c
@@ -2407,7 +2407,7 @@ 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 57b5e66..59d5925 100644
--- a/net/mac80211/scan.c
+++ b/net/mac80211/scan.c
@@ -293,7 +293,9 @@ 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;
@@ -301,7 +303,8 @@ 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);
@@ -341,13 +344,53 @@ 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;
+
+ local->scan_probe_once = false;
+ if (local->scan_req->can_scan_one) {
+ struct sta_info *sta;
+ mutex_lock(&local->iflist_mtx);
+ list_for_each_entry(sdata, &local->interfaces, list) {
+ if (!ieee80211_sdata_running(sdata))
+ continue;
+
+ if (sdata->vif.type != NL80211_IFTYPE_STATION)
+ avifs++;
+ else
+ svifs++;
+ }
+ mutex_unlock(&local->iflist_mtx);
+
+ rcu_read_lock();
+ list_for_each_entry_rcu(sta, &local->sta_list, list) {
+ if (!ieee80211_sdata_running(sta->sdata))
+ continue;
+ if (sta->sdata->vif.type != NL80211_IFTYPE_STATION)
+ continue;
+ if (test_sta_flags(sta, WLAN_STA_ASSOC))
+ avifs++;
+ }
+ rcu_read_unlock();
+
+ /* If one sta is associated, we don't want another to start
+ * scanning on all channels, as that will interfere with the
+ * one already associated.
+ */
+ if ((avifs > 1) || ((avifs == 1) && (svifs > 1)))
+ local->scan_probe_once = true;
+ }
- ieee80211_offchannel_stop_beaconing(local);
+ drv_sw_scan_start(local);
- local->leave_oper_channel_time = 0;
+ 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);
@@ -460,7 +503,8 @@ 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;
}
@@ -529,10 +573,13 @@ 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;
@@ -567,14 +614,15 @@ 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;
@@ -588,19 +636,25 @@ 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;
+ }
}
/*
@@ -616,6 +670,7 @@ 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;
}
@@ -638,6 +693,7 @@ 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;
}
diff --git a/net/wireless/nl80211.c b/net/wireless/nl80211.c
index 4ff827e..b45646e 100644
--- a/net/wireless/nl80211.c
+++ b/net/wireless/nl80211.c
@@ -138,6 +138,7 @@ static const struct nla_policy nl80211_policy[NL80211_ATTR_MAX+1] = {
[NL80211_ATTR_CONTROL_PORT] = { .type = NLA_FLAG },
[NL80211_ATTR_CONTROL_PORT_ETHERTYPE] = { .type = NLA_U16 },
[NL80211_ATTR_CONTROL_PORT_NO_ENCRYPT] = { .type = NLA_FLAG },
+ [NL80211_ATTR_SCAN_ONE_IF_ASSOC] = { .type = NLA_FLAG },
[NL80211_ATTR_PRIVACY] = { .type = NLA_FLAG },
[NL80211_ATTR_CIPHER_SUITE_GROUP] = { .type = NLA_U32 },
[NL80211_ATTR_WPA_VERSIONS] = { .type = NLA_U32 },
@@ -3217,6 +3218,11 @@ static int nl80211_trigger_scan(struct sk_buff *skb, struct genl_info *info)
goto out;
}
+ if (info->attrs[NL80211_ATTR_SCAN_ONE_IF_ASSOC])
+ request->can_scan_one = true;
+ else
+ request->can_scan_one = false;
+
if (n_ssids)
request->ssids = (void *)&request->channels[n_channels];
request->n_ssids = n_ssids;
diff --git a/net/wireless/sme.c b/net/wireless/sme.c
index f161b98..87b0cd7 100644
--- a/net/wireless/sme.c
+++ b/net/wireless/sme.c
@@ -105,6 +105,11 @@ static int cfg80211_conn_scan(struct wireless_dev *wdev)
if (!request)
return -ENOMEM;
+ /* If at least one VIF on this hardware is already associated, then
+ * only scan on the active channel.
+ */
+ request->can_scan_one = true;
+
if (wdev->conn->params.channel)
request->channels[0] = wdev->conn->params.channel;
else {
--
1.7.2.2
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