diff options
Diffstat (limited to 'net/mac80211/scan.c')
-rw-r--r-- | net/mac80211/scan.c | 382 |
1 files changed, 182 insertions, 200 deletions
diff --git a/net/mac80211/scan.c b/net/mac80211/scan.c index f934c9620b73..e1b0be7a57b9 100644 --- a/net/mac80211/scan.c +++ b/net/mac80211/scan.c @@ -12,9 +12,11 @@ * published by the Free Software Foundation. */ -#include <linux/wireless.h> #include <linux/if_arp.h> #include <linux/rtnetlink.h> +#include <linux/pm_qos_params.h> +#include <net/sch_generic.h> +#include <linux/slab.h> #include <net/mac80211.h> #include "ieee80211_i.h" @@ -29,16 +31,19 @@ struct ieee80211_bss * ieee80211_rx_bss_get(struct ieee80211_local *local, u8 *bssid, int freq, u8 *ssid, u8 ssid_len) { - return (void *)cfg80211_get_bss(local->hw.wiphy, - ieee80211_get_channel(local->hw.wiphy, - freq), - bssid, ssid, ssid_len, - 0, 0); + struct cfg80211_bss *cbss; + + cbss = cfg80211_get_bss(local->hw.wiphy, + ieee80211_get_channel(local->hw.wiphy, freq), + bssid, ssid, ssid_len, 0, 0); + if (!cbss) + return NULL; + return (void *)cbss->priv; } static void ieee80211_rx_bss_free(struct cfg80211_bss *cbss) { - struct ieee80211_bss *bss = (void *)cbss; + struct ieee80211_bss *bss = (void *)cbss->priv; kfree(bss_mesh_id(bss)); kfree(bss_mesh_cfg(bss)); @@ -47,7 +52,26 @@ static void ieee80211_rx_bss_free(struct cfg80211_bss *cbss) void ieee80211_rx_bss_put(struct ieee80211_local *local, struct ieee80211_bss *bss) { - cfg80211_put_bss((struct cfg80211_bss *)bss); + if (!bss) + return; + cfg80211_put_bss(container_of((void *)bss, struct cfg80211_bss, priv)); +} + +static bool is_uapsd_supported(struct ieee802_11_elems *elems) +{ + u8 qos_info; + + if (elems->wmm_info && elems->wmm_info_len == 7 + && elems->wmm_info[5] == 1) + qos_info = elems->wmm_info[6]; + else if (elems->wmm_param && elems->wmm_param_len == 24 + && elems->wmm_param[5] == 1) + qos_info = elems->wmm_param[6]; + else + /* no valid wmm information or parameter element found */ + return false; + + return qos_info & IEEE80211_WMM_IE_AP_QOSINFO_UAPSD; } struct ieee80211_bss * @@ -59,8 +83,9 @@ ieee80211_bss_info_update(struct ieee80211_local *local, struct ieee80211_channel *channel, bool beacon) { + struct cfg80211_bss *cbss; struct ieee80211_bss *bss; - int clen; + int clen, srlen; s32 signal = 0; if (local->hw.flags & IEEE80211_HW_SIGNAL_DBM) @@ -68,13 +93,14 @@ ieee80211_bss_info_update(struct ieee80211_local *local, else if (local->hw.flags & IEEE80211_HW_SIGNAL_UNSPEC) signal = (rx_status->signal * 100) / local->hw.max_signal; - bss = (void *)cfg80211_inform_bss_frame(local->hw.wiphy, channel, - mgmt, len, signal, GFP_ATOMIC); + cbss = cfg80211_inform_bss_frame(local->hw.wiphy, channel, + mgmt, len, signal, GFP_ATOMIC); - if (!bss) + if (!cbss) return NULL; - bss->cbss.free_priv = ieee80211_rx_bss_free; + cbss->free_priv = ieee80211_rx_bss_free; + bss = (void *)cbss->priv; /* save the ERP value so that it is available at association time */ if (elems->erp_info && elems->erp_info_len >= 1) { @@ -88,29 +114,27 @@ ieee80211_bss_info_update(struct ieee80211_local *local, bss->dtim_period = tim_ie->dtim_period; } - /* set default value for buggy AP/no TIM element */ - if (bss->dtim_period == 0) - bss->dtim_period = 1; - - bss->supp_rates_len = 0; + /* replace old supported rates if we get new values */ + srlen = 0; if (elems->supp_rates) { - clen = IEEE80211_MAX_SUPP_RATES - bss->supp_rates_len; + clen = IEEE80211_MAX_SUPP_RATES; if (clen > elems->supp_rates_len) clen = elems->supp_rates_len; - memcpy(&bss->supp_rates[bss->supp_rates_len], elems->supp_rates, - clen); - bss->supp_rates_len += clen; + memcpy(bss->supp_rates, elems->supp_rates, clen); + srlen += clen; } if (elems->ext_supp_rates) { - clen = IEEE80211_MAX_SUPP_RATES - bss->supp_rates_len; + clen = IEEE80211_MAX_SUPP_RATES - srlen; if (clen > elems->ext_supp_rates_len) clen = elems->ext_supp_rates_len; - memcpy(&bss->supp_rates[bss->supp_rates_len], - elems->ext_supp_rates, clen); - bss->supp_rates_len += clen; + memcpy(bss->supp_rates + srlen, elems->ext_supp_rates, clen); + srlen += clen; } + if (srlen) + bss->supp_rates_len = srlen; bss->wmm_used = elems->wmm_param || elems->wmm_info; + bss->uapsd_supported = is_uapsd_supported(elems); if (!beacon) bss->last_probe_resp = jiffies; @@ -147,7 +171,7 @@ ieee80211_scan_rx(struct ieee80211_sub_if_data *sdata, struct sk_buff *skb) presp = ieee80211_is_probe_resp(fc); if (presp) { /* ignore ProbeResp to foreign address */ - if (memcmp(mgmt->da, sdata->dev->dev_addr, ETH_ALEN)) + if (memcmp(mgmt->da, sdata->vif.addr, ETH_ALEN)) return RX_DROP_MONITOR; presp = true; @@ -220,84 +244,13 @@ static bool ieee80211_prep_hw_scan(struct ieee80211_local *local) return true; } -/* - * inform AP that we will go to sleep so that it will buffer the frames - * while we scan - */ -static void ieee80211_scan_ps_enable(struct ieee80211_sub_if_data *sdata) -{ - struct ieee80211_local *local = sdata->local; - - local->scan_ps_enabled = false; - - /* FIXME: what to do when local->pspolling is true? */ - - del_timer_sync(&local->dynamic_ps_timer); - cancel_work_sync(&local->dynamic_ps_enable_work); - - if (local->hw.conf.flags & IEEE80211_CONF_PS) { - local->scan_ps_enabled = true; - local->hw.conf.flags &= ~IEEE80211_CONF_PS; - ieee80211_hw_config(local, IEEE80211_CONF_CHANGE_PS); - } - - if (!(local->scan_ps_enabled) || - !(local->hw.flags & IEEE80211_HW_PS_NULLFUNC_STACK)) - /* - * If power save was enabled, no need to send a nullfunc - * frame because AP knows that we are sleeping. But if the - * hardware is creating the nullfunc frame for power save - * status (ie. IEEE80211_HW_PS_NULLFUNC_STACK is not - * enabled) and power save was enabled, the firmware just - * sent a null frame with power save disabled. So we need - * to send a new nullfunc frame to inform the AP that we - * are again sleeping. - */ - ieee80211_send_nullfunc(local, sdata, 1); -} - -/* inform AP that we are awake again, unless power save is enabled */ -static void ieee80211_scan_ps_disable(struct ieee80211_sub_if_data *sdata) -{ - struct ieee80211_local *local = sdata->local; - - if (!local->ps_sdata) - ieee80211_send_nullfunc(local, sdata, 0); - else if (local->scan_ps_enabled) { - /* - * In !IEEE80211_HW_PS_NULLFUNC_STACK case the hardware - * will send a nullfunc frame with the powersave bit set - * even though the AP already knows that we are sleeping. - * This could be avoided by sending a null frame with power - * save bit disabled before enabling the power save, but - * this doesn't gain anything. - * - * When IEEE80211_HW_PS_NULLFUNC_STACK is enabled, no need - * to send a nullfunc frame because AP already knows that - * we are sleeping, let's just enable power save mode in - * hardware. - */ - local->hw.conf.flags |= IEEE80211_CONF_PS; - ieee80211_hw_config(local, IEEE80211_CONF_CHANGE_PS); - } else if (local->hw.conf.dynamic_ps_timeout > 0) { - /* - * If IEEE80211_CONF_PS was not set and the dynamic_ps_timer - * had been running before leaving the operating channel, - * restart the timer now and send a nullfunc frame to inform - * the AP that we are awake. - */ - ieee80211_send_nullfunc(local, sdata, 0); - mod_timer(&local->dynamic_ps_timer, jiffies + - msecs_to_jiffies(local->hw.conf.dynamic_ps_timeout)); - } -} - void ieee80211_scan_completed(struct ieee80211_hw *hw, bool aborted) { struct ieee80211_local *local = hw_to_local(hw); - struct ieee80211_sub_if_data *sdata; bool was_hw_scan; + trace_api_scan_completed(local, aborted); + mutex_lock(&local->scan_mtx); /* @@ -344,41 +297,19 @@ void ieee80211_scan_completed(struct ieee80211_hw *hw, bool aborted) drv_sw_scan_complete(local); - mutex_lock(&local->iflist_mtx); - list_for_each_entry(sdata, &local->interfaces, list) { - if (!netif_running(sdata->dev)) - continue; - - /* Tell AP we're back */ - if (sdata->vif.type == NL80211_IFTYPE_STATION) { - if (sdata->u.mgd.associated) { - ieee80211_scan_ps_disable(sdata); - netif_tx_wake_all_queues(sdata->dev); - } - } else - netif_tx_wake_all_queues(sdata->dev); - - /* re-enable beaconing */ - if (sdata->vif.type == NL80211_IFTYPE_AP || - sdata->vif.type == NL80211_IFTYPE_ADHOC || - sdata->vif.type == NL80211_IFTYPE_MESH_POINT) - ieee80211_bss_info_change_notify( - sdata, BSS_CHANGED_BEACON_ENABLED); - } - mutex_unlock(&local->iflist_mtx); + ieee80211_offchannel_return(local, true); done: ieee80211_recalc_idle(local); ieee80211_mlme_notify_scan_completed(local); ieee80211_ibss_notify_scan_completed(local); ieee80211_mesh_notify_scan_completed(local); + ieee80211_queue_work(&local->hw, &local->work_work); } EXPORT_SYMBOL(ieee80211_scan_completed); static int ieee80211_start_sw_scan(struct ieee80211_local *local) { - struct ieee80211_sub_if_data *sdata; - /* * Hardware/driver doesn't support hw_scan, so use software * scanning instead. First send a nullfunc frame with power save @@ -394,33 +325,16 @@ static int ieee80211_start_sw_scan(struct ieee80211_local *local) */ drv_sw_scan_start(local); - mutex_lock(&local->iflist_mtx); - list_for_each_entry(sdata, &local->interfaces, list) { - if (!netif_running(sdata->dev)) - continue; - - /* disable beaconing */ - if (sdata->vif.type == NL80211_IFTYPE_AP || - sdata->vif.type == NL80211_IFTYPE_ADHOC || - sdata->vif.type == NL80211_IFTYPE_MESH_POINT) - ieee80211_bss_info_change_notify( - sdata, BSS_CHANGED_BEACON_ENABLED); - - /* - * only handle non-STA interfaces here, STA interfaces - * are handled in the scan state machine - */ - if (sdata->vif.type != NL80211_IFTYPE_STATION) - netif_tx_stop_all_queues(sdata->dev); - } - mutex_unlock(&local->iflist_mtx); + ieee80211_offchannel_stop_beaconing(local); + local->leave_oper_channel_time = 0; local->next_scan_state = SCAN_DECISION; local->scan_channel_idx = 0; + drv_flush(local, false); + ieee80211_configure_filter(local); - /* TODO: start scan as soon as all nullfunc frames are ACKed */ ieee80211_queue_delayed_work(&local->hw, &local->scan_work, IEEE80211_CHANNEL_TIME); @@ -433,12 +347,18 @@ static int __ieee80211_start_scan(struct ieee80211_sub_if_data *sdata, struct cfg80211_scan_request *req) { struct ieee80211_local *local = sdata->local; - struct ieee80211_if_managed *ifmgd = &sdata->u.mgd; int rc; if (local->scan_req) return -EBUSY; + if (!list_empty(&local->work_list)) { + /* wait for the work to finish/time out */ + local->scan_req = req; + local->scan_sdata = sdata; + return 0; + } + if (local->ops->hw_scan) { u8 *ies; @@ -458,32 +378,33 @@ static int __ieee80211_start_scan(struct ieee80211_sub_if_data *sdata, local->hw_scan_req->ie = ies; local->hw_scan_band = 0; + + /* + * After allocating local->hw_scan_req, we must + * go through until ieee80211_prep_hw_scan(), so + * anything that might be changed here and leave + * this function early must not go after this + * allocation. + */ } local->scan_req = req; local->scan_sdata = sdata; - if (req != local->int_scan_req && - sdata->vif.type == NL80211_IFTYPE_STATION && - !list_empty(&ifmgd->work_list)) { - /* actually wait for the work it's doing to finish/time out */ - set_bit(IEEE80211_STA_REQ_SCAN, &ifmgd->request); - return 0; - } - if (local->ops->hw_scan) __set_bit(SCAN_HW_SCANNING, &local->scanning); else __set_bit(SCAN_SW_SCANNING, &local->scanning); + /* * Kicking off the scan need not be protected, * only the scan variable stuff, since now * local->scan_req is assigned and other callers * will abort their scan attempts. * - * This avoids getting a scan_mtx -> iflist_mtx - * dependency, so that the scan completed calls - * have more locking freedom. + * This avoids too many locking dependencies + * so that the scan completed calls have more + * locking freedom. */ ieee80211_recalc_idle(local); @@ -491,7 +412,7 @@ static int __ieee80211_start_scan(struct ieee80211_sub_if_data *sdata, if (local->ops->hw_scan) { WARN_ON(!ieee80211_prep_hw_scan(local)); - rc = drv_hw_scan(local, local->hw_scan_req); + rc = drv_hw_scan(local, sdata, local->hw_scan_req); } else rc = ieee80211_start_sw_scan(local); @@ -511,11 +432,28 @@ static int __ieee80211_start_scan(struct ieee80211_sub_if_data *sdata, return rc; } +static unsigned long +ieee80211_scan_get_channel_time(struct ieee80211_channel *chan) +{ + /* + * TODO: channel switching also consumes quite some time, + * add that delay as well to get a better estimation + */ + if (chan->flags & IEEE80211_CHAN_PASSIVE_SCAN) + return IEEE80211_PASSIVE_CHANNEL_TIME; + return IEEE80211_PROBE_DELAY + IEEE80211_CHANNEL_TIME; +} + static int ieee80211_scan_state_decision(struct ieee80211_local *local, unsigned long *next_delay) { bool associated = false; + bool tx_empty = true; + bool bad_latency; + bool listen_int_exceeded; + unsigned long min_beacon_int = 0; struct ieee80211_sub_if_data *sdata; + 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) { @@ -523,16 +461,29 @@ static int ieee80211_scan_state_decision(struct ieee80211_local *local, return 1; } - /* check if at least one STA interface is associated */ + /* + * check if at least one STA interface is associated, + * check if at least one STA interface has pending tx frames + * and grab the lowest used beacon interval + */ mutex_lock(&local->iflist_mtx); list_for_each_entry(sdata, &local->interfaces, list) { - if (!netif_running(sdata->dev)) + if (!ieee80211_sdata_running(sdata)) continue; if (sdata->vif.type == NL80211_IFTYPE_STATION) { if (sdata->u.mgd.associated) { associated = true; - break; + + if (sdata->vif.bss_conf.beacon_int < + min_beacon_int || min_beacon_int == 0) + min_beacon_int = + sdata->vif.bss_conf.beacon_int; + + if (!qdisc_all_tx_empty(sdata->dev)) { + tx_empty = false; + break; + } } } } @@ -541,11 +492,34 @@ static int ieee80211_scan_state_decision(struct ieee80211_local *local, if (local->scan_channel) { /* * we're currently scanning a different channel, let's - * switch back to the operating channel now if at least - * one interface is associated. Otherwise just scan the - * next channel + * see if we can scan another channel without interfering + * with the current traffic situation. + * + * Since we don't know if the AP has pending frames for us + * we can only check for our tx queues and use the current + * pm_qos requirements for rx. Hence, if no tx traffic occurs + * at all we will scan as many channels in a row as the pm_qos + * latency allows us to. Additionally we also check for the + * currently negotiated listen interval to prevent losing + * frames unnecessarily. + * + * Otherwise switch back to the operating channel. */ - if (associated) + next_chan = local->scan_req->channels[local->scan_channel_idx]; + + bad_latency = time_after(jiffies + + ieee80211_scan_get_channel_time(next_chan), + local->leave_oper_channel_time + + usecs_to_jiffies(pm_qos_request(PM_QOS_NETWORK_LATENCY))); + + listen_int_exceeded = time_after(jiffies + + ieee80211_scan_get_channel_time(next_chan), + local->leave_oper_channel_time + + usecs_to_jiffies(min_beacon_int * 1024) * + local->hw.conf.listen_interval); + + if (associated && ( !tx_empty || bad_latency || + listen_int_exceeded)) local->next_scan_state = SCAN_ENTER_OPER_CHANNEL; else local->next_scan_state = SCAN_SET_CHANNEL; @@ -564,56 +538,38 @@ static int ieee80211_scan_state_decision(struct ieee80211_local *local, static void ieee80211_scan_state_leave_oper_channel(struct ieee80211_local *local, unsigned long *next_delay) { - struct ieee80211_sub_if_data *sdata; + ieee80211_offchannel_stop_station(local); + + __set_bit(SCAN_OFF_CHANNEL, &local->scanning); /* - * notify the AP about us leaving the channel and stop all STA interfaces + * What if the nullfunc frames didn't arrive? */ - mutex_lock(&local->iflist_mtx); - list_for_each_entry(sdata, &local->interfaces, list) { - if (!netif_running(sdata->dev)) - continue; - - if (sdata->vif.type == NL80211_IFTYPE_STATION) { - netif_tx_stop_all_queues(sdata->dev); - if (sdata->u.mgd.associated) - ieee80211_scan_ps_enable(sdata); - } - } - mutex_unlock(&local->iflist_mtx); + drv_flush(local, false); + if (local->ops->flush) + *next_delay = 0; + else + *next_delay = HZ / 10; - __set_bit(SCAN_OFF_CHANNEL, &local->scanning); + /* remember when we left the operating channel */ + local->leave_oper_channel_time = jiffies; /* advance to the next channel to be scanned */ - *next_delay = HZ / 10; local->next_scan_state = SCAN_SET_CHANNEL; } static void ieee80211_scan_state_enter_oper_channel(struct ieee80211_local *local, unsigned long *next_delay) { - struct ieee80211_sub_if_data *sdata = local->scan_sdata; - /* switch back to the operating channel */ local->scan_channel = NULL; ieee80211_hw_config(local, IEEE80211_CONF_CHANGE_CHANNEL); /* - * notify the AP about us being back and restart all STA interfaces + * Only re-enable station mode interface now; beaconing will be + * re-enabled once the full scan has been completed. */ - mutex_lock(&local->iflist_mtx); - list_for_each_entry(sdata, &local->interfaces, list) { - if (!netif_running(sdata->dev)) - continue; - - /* Tell AP we're back */ - if (sdata->vif.type == NL80211_IFTYPE_STATION) { - if (sdata->u.mgd.associated) - ieee80211_scan_ps_disable(sdata); - netif_tx_wake_all_queues(sdata->dev); - } - } - mutex_unlock(&local->iflist_mtx); + ieee80211_offchannel_return(local, false); __clear_bit(SCAN_OFF_CHANNEL, &local->scanning); @@ -700,7 +656,7 @@ void ieee80211_scan_work(struct work_struct *work) } if (local->hw_scan_req) { - int rc = drv_hw_scan(local, local->hw_scan_req); + int rc = drv_hw_scan(local, sdata, local->hw_scan_req); mutex_unlock(&local->scan_mtx); if (rc) ieee80211_scan_completed(&local->hw, true); @@ -727,7 +683,7 @@ void ieee80211_scan_work(struct work_struct *work) /* * Avoid re-scheduling when the sdata is going away. */ - if (!netif_running(sdata->dev)) { + if (!ieee80211_sdata_running(sdata)) { ieee80211_scan_completed(&local->hw, true); return; } @@ -773,10 +729,12 @@ int ieee80211_request_scan(struct ieee80211_sub_if_data *sdata, } int ieee80211_request_internal_scan(struct ieee80211_sub_if_data *sdata, - const u8 *ssid, u8 ssid_len) + const u8 *ssid, u8 ssid_len, + struct ieee80211_channel *chan) { struct ieee80211_local *local = sdata->local; int ret = -EBUSY; + enum nl80211_band band; mutex_lock(&local->scan_mtx); @@ -784,6 +742,30 @@ int ieee80211_request_internal_scan(struct ieee80211_sub_if_data *sdata, if (local->scan_req) goto unlock; + /* fill internal scan request */ + if (!chan) { + int i, nchan = 0; + + for (band = 0; band < IEEE80211_NUM_BANDS; band++) { + if (!local->hw.wiphy->bands[band]) + continue; + for (i = 0; + i < local->hw.wiphy->bands[band]->n_channels; + i++) { + local->int_scan_req->channels[nchan] = + &local->hw.wiphy->bands[band]->channels[i]; + nchan++; + } + } + + local->int_scan_req->n_channels = nchan; + } else { + local->int_scan_req->channels[0] = chan; + local->int_scan_req->n_channels = 1; + } + + local->int_scan_req->ssids = &local->scan_ssid; + local->int_scan_req->n_ssids = 1; memcpy(local->int_scan_req->ssids[0].ssid, ssid, IEEE80211_MAX_SSID_LEN); local->int_scan_req->ssids[0].ssid_len = ssid_len; |