mac80211: inform the driver about update of dtim_period
Currently, when the driver requires the DTIM period,
mac80211 will wait to hear a beacon before association.
This behavior is suboptimal since some drivers may be
able to deal with knowing the DTIM period after the
association, if they get it at all.
To address this, notify the drivers with bss_info_changed
with the new BSS_CHANGED_DTIM_PERIOD flag when the DTIM
becomes known. This might be when changing to associated,
or later when the entire association was done with only
probe response information.
Rename the hardware flag for the current behaviour to
IEEE80211_HW_NEED_DTIM_BEFORE_ASSOC to more accurately
reflect its behaviour. IEEE80211_HW_NEED_DTIM_PERIOD is
no longer accurate as all drivers get the DTIM period
now, just not before association.
Signed-off-by: Emmanuel Grumbach <emmanuel.grumbach@intel.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
diff --git a/drivers/net/wireless/ath/carl9170/main.c b/drivers/net/wireless/ath/carl9170/main.c
index ef82751..f293b3f 100644
--- a/drivers/net/wireless/ath/carl9170/main.c
+++ b/drivers/net/wireless/ath/carl9170/main.c
@@ -1853,7 +1853,7 @@
IEEE80211_HW_REPORTS_TX_ACK_STATUS |
IEEE80211_HW_SUPPORTS_PS |
IEEE80211_HW_PS_NULLFUNC_STACK |
- IEEE80211_HW_NEED_DTIM_PERIOD |
+ IEEE80211_HW_NEED_DTIM_BEFORE_ASSOC |
IEEE80211_HW_SIGNAL_DBM;
if (!modparam_noht) {
diff --git a/drivers/net/wireless/iwlegacy/4965-mac.c b/drivers/net/wireless/iwlegacy/4965-mac.c
index f1dc040..d3cc776 100644
--- a/drivers/net/wireless/iwlegacy/4965-mac.c
+++ b/drivers/net/wireless/iwlegacy/4965-mac.c
@@ -5711,7 +5711,7 @@
/* Tell mac80211 our characteristics */
hw->flags =
IEEE80211_HW_SIGNAL_DBM | IEEE80211_HW_AMPDU_AGGREGATION |
- IEEE80211_HW_NEED_DTIM_PERIOD | IEEE80211_HW_SPECTRUM_MGMT |
+ IEEE80211_HW_NEED_DTIM_BEFORE_ASSOC | IEEE80211_HW_SPECTRUM_MGMT |
IEEE80211_HW_REPORTS_TX_ACK_STATUS | IEEE80211_HW_SUPPORTS_PS |
IEEE80211_HW_SUPPORTS_DYNAMIC_PS;
if (il->cfg->sku & IL_SKU_N)
diff --git a/drivers/net/wireless/iwlwifi/dvm/mac80211.c b/drivers/net/wireless/iwlwifi/dvm/mac80211.c
index fa43c0d..8e5c5c5 100644
--- a/drivers/net/wireless/iwlwifi/dvm/mac80211.c
+++ b/drivers/net/wireless/iwlwifi/dvm/mac80211.c
@@ -145,7 +145,7 @@
/* Tell mac80211 our characteristics */
hw->flags = IEEE80211_HW_SIGNAL_DBM |
IEEE80211_HW_AMPDU_AGGREGATION |
- IEEE80211_HW_NEED_DTIM_PERIOD |
+ IEEE80211_HW_NEED_DTIM_BEFORE_ASSOC |
IEEE80211_HW_SPECTRUM_MGMT |
IEEE80211_HW_REPORTS_TX_ACK_STATUS |
IEEE80211_HW_QUEUE_CONTROL |
diff --git a/include/net/mac80211.h b/include/net/mac80211.h
index 7a27e00..398b6ca4 100644
--- a/include/net/mac80211.h
+++ b/include/net/mac80211.h
@@ -208,6 +208,8 @@
* @BSS_CHANGED_TXPOWER: TX power setting changed for this interface
* @BSS_CHANGED_P2P_PS: P2P powersave settings (CTWindow, opportunistic PS)
* changed (currently only in P2P client mode, GO mode will be later)
+ * @BSS_CHANGED_DTIM_PERIOD: the DTIM period value was changed (set when
+ * it becomes valid, managed mode only)
*/
enum ieee80211_bss_change {
BSS_CHANGED_ASSOC = 1<<0,
@@ -230,6 +232,7 @@
BSS_CHANGED_PS = 1<<17,
BSS_CHANGED_TXPOWER = 1<<18,
BSS_CHANGED_P2P_PS = 1<<19,
+ BSS_CHANGED_DTIM_PERIOD = 1<<20,
/* when adding here, make sure to change ieee80211_reconfig */
};
@@ -271,9 +274,8 @@
* if the hardware cannot handle this it must set the
* IEEE80211_HW_2GHZ_SHORT_SLOT_INCAPABLE hardware flag
* @dtim_period: num of beacons before the next DTIM, for beaconing,
- * valid in station mode only while @assoc is true and if also
- * requested by %IEEE80211_HW_NEED_DTIM_PERIOD (cf. also hw conf
- * @ps_dtim_period)
+ * valid in station mode only if after the driver was notified
+ * with the %BSS_CHANGED_DTIM_PERIOD flag, will be non-zero then.
* @sync_tsf: last beacon's/probe response's TSF timestamp (could be old
* as it may have been received during scanning long ago)
* @sync_device_ts: the device timestamp corresponding to the sync_tsf,
@@ -1328,9 +1330,9 @@
* When this flag is set, signaling beacon-loss will cause an immediate
* change to disassociated state.
*
- * @IEEE80211_HW_NEED_DTIM_PERIOD:
- * This device needs to know the DTIM period for the BSS before
- * associating.
+ * @IEEE80211_HW_NEED_DTIM_BEFORE_ASSOC:
+ * This device needs to get data from beacon before association (i.e.
+ * dtim_period).
*
* @IEEE80211_HW_SUPPORTS_PER_STA_GTK: The device's crypto engine supports
* per-station GTKs as used by IBSS RSN or during fast transition. If
@@ -1375,7 +1377,7 @@
IEEE80211_HW_2GHZ_SHORT_PREAMBLE_INCAPABLE = 1<<4,
IEEE80211_HW_SIGNAL_UNSPEC = 1<<5,
IEEE80211_HW_SIGNAL_DBM = 1<<6,
- IEEE80211_HW_NEED_DTIM_PERIOD = 1<<7,
+ IEEE80211_HW_NEED_DTIM_BEFORE_ASSOC = 1<<7,
IEEE80211_HW_SPECTRUM_MGMT = 1<<8,
IEEE80211_HW_AMPDU_AGGREGATION = 1<<9,
IEEE80211_HW_SUPPORTS_PS = 1<<10,
diff --git a/net/mac80211/debugfs.c b/net/mac80211/debugfs.c
index 466f4b4..8e604099 100644
--- a/net/mac80211/debugfs.c
+++ b/net/mac80211/debugfs.c
@@ -121,8 +121,8 @@
sf += snprintf(buf + sf, mxln - sf, "SIGNAL_UNSPEC\n");
if (local->hw.flags & IEEE80211_HW_SIGNAL_DBM)
sf += snprintf(buf + sf, mxln - sf, "SIGNAL_DBM\n");
- if (local->hw.flags & IEEE80211_HW_NEED_DTIM_PERIOD)
- sf += snprintf(buf + sf, mxln - sf, "NEED_DTIM_PERIOD\n");
+ if (local->hw.flags & IEEE80211_HW_NEED_DTIM_BEFORE_ASSOC)
+ sf += snprintf(buf + sf, mxln - sf, "NEED_DTIM_BEFORE_ASSOC\n");
if (local->hw.flags & IEEE80211_HW_SPECTRUM_MGMT)
sf += snprintf(buf + sf, mxln - sf, "SPECTRUM_MGMT\n");
if (local->hw.flags & IEEE80211_HW_AMPDU_AGGREGATION)
diff --git a/net/mac80211/ieee80211_i.h b/net/mac80211/ieee80211_i.h
index 2f50be7..5ce0b6b 100644
--- a/net/mac80211/ieee80211_i.h
+++ b/net/mac80211/ieee80211_i.h
@@ -399,7 +399,7 @@
u8 ssid_len;
u8 supp_rates_len;
bool wmm, uapsd;
- bool have_beacon;
+ bool have_beacon, need_beacon;
bool synced;
u8 ap_ht_param;
diff --git a/net/mac80211/mlme.c b/net/mac80211/mlme.c
index d79b9cd..a5dba67 100644
--- a/net/mac80211/mlme.c
+++ b/net/mac80211/mlme.c
@@ -1445,7 +1445,7 @@
ieee80211_led_assoc(local, 1);
- if (local->hw.flags & IEEE80211_HW_NEED_DTIM_PERIOD) {
+ if (sdata->u.mgd.assoc_data->have_beacon) {
/*
* If the AP is buggy we may get here with no DTIM period
* known, so assume it's 1 which is the only safe assumption
@@ -1453,6 +1453,7 @@
* probably just won't work at all.
*/
bss_conf->dtim_period = sdata->u.mgd.dtim_period ?: 1;
+ bss_info_changed |= BSS_CHANGED_DTIM_PERIOD;
} else {
bss_conf->dtim_period = 0;
}
@@ -2548,13 +2549,14 @@
chan = chanctx_conf->def.chan;
rcu_read_unlock();
- if (ifmgd->assoc_data && !ifmgd->assoc_data->have_beacon &&
+ if (ifmgd->assoc_data && ifmgd->assoc_data->need_beacon &&
ether_addr_equal(mgmt->bssid, ifmgd->assoc_data->bss->bssid)) {
ieee802_11_parse_elems(mgmt->u.beacon.variable,
len - baselen, &elems);
ieee80211_rx_bss_info(sdata, mgmt, len, rx_status, &elems);
ifmgd->assoc_data->have_beacon = true;
+ ifmgd->assoc_data->need_beacon = false;
/* continue assoc process */
ifmgd->assoc_data->timeout = jiffies;
run_again(ifmgd, ifmgd->assoc_data->timeout);
@@ -2711,6 +2713,19 @@
elems.wmm_param_len))
changed |= BSS_CHANGED_QOS;
+ /*
+ * If we haven't had a beacon before, tell the driver about the
+ * DTIM period now.
+ */
+ if (!bss_conf->dtim_period) {
+ /* a few bogus AP send dtim_period = 0 or no TIM IE */
+ if (elems.tim)
+ bss_conf->dtim_period = elems.tim->dtim_period ?: 1;
+ else
+ bss_conf->dtim_period = 1;
+ changed |= BSS_CHANGED_DTIM_PERIOD;
+ }
+
if (elems.erp_info && elems.erp_info_len >= 1) {
erp_valid = true;
erp_value = elems.erp_info[0];
@@ -2989,7 +3004,8 @@
if (ifmgd->assoc_data &&
time_after(jiffies, ifmgd->assoc_data->timeout)) {
- if (!ifmgd->assoc_data->have_beacon ||
+ if ((ifmgd->assoc_data->need_beacon &&
+ !ifmgd->assoc_data->have_beacon) ||
ieee80211_do_assoc(sdata)) {
u8 bssid[ETH_ALEN];
@@ -3776,6 +3792,7 @@
struct ieee80211_if_managed *ifmgd = &sdata->u.mgd;
struct ieee80211_bss *bss = (void *)req->bss->priv;
struct ieee80211_mgd_assoc_data *assoc_data;
+ const struct cfg80211_bss_ies *beacon_ies;
struct ieee80211_supported_band *sband;
const u8 *ssidie, *ht_ie, *vht_ie;
int i, err;
@@ -3941,38 +3958,35 @@
if (err)
goto err_clear;
- if (sdata->local->hw.flags & IEEE80211_HW_NEED_DTIM_PERIOD) {
- const struct cfg80211_bss_ies *beacon_ies;
+ rcu_read_lock();
+ beacon_ies = rcu_dereference(req->bss->beacon_ies);
- rcu_read_lock();
- beacon_ies = rcu_dereference(req->bss->beacon_ies);
- if (!beacon_ies) {
- /*
- * Wait up to one beacon interval ...
- * should this be more if we miss one?
- */
- sdata_info(sdata, "waiting for beacon from %pM\n",
- ifmgd->bssid);
- assoc_data->timeout =
- TU_TO_EXP_TIME(req->bss->beacon_interval);
- } else {
- const u8 *tim_ie = cfg80211_find_ie(WLAN_EID_TIM,
- beacon_ies->data,
- beacon_ies->len);
- if (tim_ie && tim_ie[1] >=
- sizeof(struct ieee80211_tim_ie)) {
- const struct ieee80211_tim_ie *tim;
- tim = (void *)(tim_ie + 2);
- ifmgd->dtim_period = tim->dtim_period;
- }
- assoc_data->have_beacon = true;
- assoc_data->timeout = jiffies;
+ if (sdata->local->hw.flags & IEEE80211_HW_NEED_DTIM_BEFORE_ASSOC &&
+ !beacon_ies) {
+ /*
+ * Wait up to one beacon interval ...
+ * should this be more if we miss one?
+ */
+ sdata_info(sdata, "waiting for beacon from %pM\n",
+ ifmgd->bssid);
+ assoc_data->timeout = TU_TO_EXP_TIME(req->bss->beacon_interval);
+ assoc_data->need_beacon = true;
+ } else if (beacon_ies) {
+ const u8 *tim_ie = cfg80211_find_ie(WLAN_EID_TIM,
+ beacon_ies->data,
+ beacon_ies->len);
+ if (tim_ie && tim_ie[1] >= sizeof(struct ieee80211_tim_ie)) {
+ const struct ieee80211_tim_ie *tim;
+ tim = (void *)(tim_ie + 2);
+ ifmgd->dtim_period = tim->dtim_period;
}
- rcu_read_unlock();
- } else {
assoc_data->have_beacon = true;
assoc_data->timeout = jiffies;
+ } else {
+ assoc_data->timeout = jiffies;
}
+ rcu_read_unlock();
+
run_again(ifmgd, assoc_data->timeout);
if (bss->corrupt_data) {
diff --git a/net/mac80211/util.c b/net/mac80211/util.c
index 7519018..1c74512 100644
--- a/net/mac80211/util.c
+++ b/net/mac80211/util.c
@@ -1538,6 +1538,10 @@
changed |= BSS_CHANGED_ASSOC |
BSS_CHANGED_ARP_FILTER |
BSS_CHANGED_PS;
+
+ if (sdata->u.mgd.dtim_period)
+ changed |= BSS_CHANGED_DTIM_PERIOD;
+
mutex_lock(&sdata->u.mgd.mtx);
ieee80211_bss_info_change_notify(sdata, changed);
mutex_unlock(&sdata->u.mgd.mtx);