diff options
Diffstat (limited to 'net/mac80211/scan.c')
| -rw-r--r-- | net/mac80211/scan.c | 977 |
1 files changed, 977 insertions, 0 deletions
diff --git a/net/mac80211/scan.c b/net/mac80211/scan.c new file mode 100644 index 00000000..669d2e32 --- /dev/null +++ b/net/mac80211/scan.c @@ -0,0 +1,977 @@ +/* + * Scanning implementation + * + * Copyright 2003, Jouni Malinen <jkmaline@cc.hut.fi> + * Copyright 2004, Instant802 Networks, Inc. + * Copyright 2005, Devicescape Software, Inc. + * Copyright 2006-2007 Jiri Benc <jbenc@suse.cz> + * Copyright 2007, Michael Wu <flamingice@sourmilk.net> + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 as + * published by the Free Software Foundation. + */ + +#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" +#include "driver-ops.h" +#include "mesh.h" + +#define IEEE80211_PROBE_DELAY (HZ / 33) +#define IEEE80211_CHANNEL_TIME (HZ / 33) +#define IEEE80211_PASSIVE_CHANNEL_TIME (HZ / 8) + +struct ieee80211_bss * +ieee80211_rx_bss_get(struct ieee80211_local *local, u8 *bssid, int freq, + u8 *ssid, u8 ssid_len) +{ + 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->priv; + + kfree(bss_mesh_id(bss)); + kfree(bss_mesh_cfg(bss)); +} + +void ieee80211_rx_bss_put(struct ieee80211_local *local, + struct ieee80211_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 * +ieee80211_bss_info_update(struct ieee80211_local *local, + struct ieee80211_rx_status *rx_status, + struct ieee80211_mgmt *mgmt, + size_t len, + struct ieee802_11_elems *elems, + struct ieee80211_channel *channel, + bool beacon) +{ + struct cfg80211_bss *cbss; + struct ieee80211_bss *bss; + int clen, srlen; + s32 signal = 0; + + if (local->hw.flags & IEEE80211_HW_SIGNAL_DBM) + signal = rx_status->signal * 100; + else if (local->hw.flags & IEEE80211_HW_SIGNAL_UNSPEC) + signal = (rx_status->signal * 100) / local->hw.max_signal; + + cbss = cfg80211_inform_bss_frame(local->hw.wiphy, channel, + mgmt, len, signal, GFP_ATOMIC); + + if (!cbss) + return NULL; + + 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) { + bss->erp_value = elems->erp_info[0]; + bss->has_erp_value = 1; + } + + if (elems->tim) { + struct ieee80211_tim_ie *tim_ie = + (struct ieee80211_tim_ie *)elems->tim; + bss->dtim_period = tim_ie->dtim_period; + } + + /* If the beacon had no TIM IE, or it was invalid, use 1 */ + if (beacon && !bss->dtim_period) + bss->dtim_period = 1; + + /* replace old supported rates if we get new values */ + srlen = 0; + if (elems->supp_rates) { + clen = IEEE80211_MAX_SUPP_RATES; + if (clen > elems->supp_rates_len) + clen = elems->supp_rates_len; + memcpy(bss->supp_rates, elems->supp_rates, clen); + srlen += clen; + } + if (elems->ext_supp_rates) { + clen = IEEE80211_MAX_SUPP_RATES - srlen; + if (clen > elems->ext_supp_rates_len) + clen = elems->ext_supp_rates_len; + 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; + + return bss; +} + +ieee80211_rx_result +ieee80211_scan_rx(struct ieee80211_sub_if_data *sdata, struct sk_buff *skb) +{ + struct ieee80211_rx_status *rx_status = IEEE80211_SKB_RXCB(skb); + struct ieee80211_mgmt *mgmt; + struct ieee80211_bss *bss; + u8 *elements; + struct ieee80211_channel *channel; + size_t baselen; + int freq; + __le16 fc; + bool presp, beacon = false; + struct ieee802_11_elems elems; + + if (skb->len < 2) + return RX_DROP_UNUSABLE; + + mgmt = (struct ieee80211_mgmt *) skb->data; + fc = mgmt->frame_control; + + if (ieee80211_is_ctl(fc)) + return RX_CONTINUE; + + if (skb->len < 24) + return RX_CONTINUE; + + presp = ieee80211_is_probe_resp(fc); + if (presp) { + /* ignore ProbeResp to foreign address */ + if (memcmp(mgmt->da, sdata->vif.addr, ETH_ALEN)) + return RX_DROP_MONITOR; + + presp = true; + elements = mgmt->u.probe_resp.variable; + baselen = offsetof(struct ieee80211_mgmt, u.probe_resp.variable); + } else { + beacon = ieee80211_is_beacon(fc); + baselen = offsetof(struct ieee80211_mgmt, u.beacon.variable); + elements = mgmt->u.beacon.variable; + } + + if (!presp && !beacon) + return RX_CONTINUE; + + if (baselen > skb->len) + return RX_DROP_MONITOR; + + ieee802_11_parse_elems(elements, skb->len - baselen, &elems); + + if (elems.ds_params && elems.ds_params_len == 1) + freq = ieee80211_channel_to_frequency(elems.ds_params[0], + rx_status->band); + else + freq = rx_status->freq; + + channel = ieee80211_get_channel(sdata->local->hw.wiphy, freq); + + if (!channel || channel->flags & IEEE80211_CHAN_DISABLED) + return RX_DROP_MONITOR; + + bss = ieee80211_bss_info_update(sdata->local, rx_status, + mgmt, skb->len, &elems, + channel, beacon); + if (bss) + ieee80211_rx_bss_put(sdata->local, bss); + + /* If we are on-operating-channel, and this packet is for the + * current channel, pass the pkt on up the stack so that + * the rest of the stack can make use of it. + */ + if (ieee80211_cfg_on_oper_channel(sdata->local) + && (channel == sdata->local->oper_channel)) + return RX_CONTINUE; + + dev_kfree_skb(skb); + return RX_QUEUED; +} + +/* return false if no more work */ +static bool ieee80211_prep_hw_scan(struct ieee80211_local *local) +{ + struct cfg80211_scan_request *req = local->scan_req; + enum ieee80211_band band; + int i, ielen, n_chans; + + do { + if (local->hw_scan_band == IEEE80211_NUM_BANDS) + return false; + + band = local->hw_scan_band; + n_chans = 0; + for (i = 0; i < req->n_channels; i++) { + if (req->channels[i]->band == band) { + local->hw_scan_req->channels[n_chans] = + req->channels[i]; + n_chans++; + } + } + + local->hw_scan_band++; + } while (!n_chans); + + local->hw_scan_req->n_channels = n_chans; + + ielen = ieee80211_build_preq_ies(local, (u8 *)local->hw_scan_req->ie, + req->ie, req->ie_len, band, (u32) -1, + 0); + local->hw_scan_req->ie_len = ielen; + + return true; +} + +static void __ieee80211_scan_completed(struct ieee80211_hw *hw, bool aborted, + bool was_hw_scan) +{ + struct ieee80211_local *local = hw_to_local(hw); + bool on_oper_chan; + bool enable_beacons = false; + + lockdep_assert_held(&local->mtx); + + /* + * It's ok to abort a not-yet-running scan (that + * we have one at all will be verified by checking + * local->scan_req next), but not to complete it + * successfully. + */ + if (WARN_ON(!local->scanning && !aborted)) + aborted = true; + + if (WARN_ON(!local->scan_req)) + return; + + if (was_hw_scan && !aborted && ieee80211_prep_hw_scan(local)) { + int rc = drv_hw_scan(local, local->scan_sdata, local->hw_scan_req); + if (rc == 0) + return; + } + + kfree(local->hw_scan_req); + local->hw_scan_req = NULL; + + if (local->scan_req != local->int_scan_req) + cfg80211_scan_done(local->scan_req, aborted); + local->scan_req = NULL; + local->scan_sdata = NULL; + + local->scanning = 0; + local->scan_channel = NULL; + + on_oper_chan = ieee80211_cfg_on_oper_channel(local); + + if (was_hw_scan || !on_oper_chan) + ieee80211_hw_config(local, IEEE80211_CONF_CHANGE_CHANNEL); + else + /* Set power back to normal operating levels. */ + ieee80211_hw_config(local, 0); + + if (!was_hw_scan) { + bool on_oper_chan2; + ieee80211_configure_filter(local); + drv_sw_scan_complete(local); + on_oper_chan2 = ieee80211_cfg_on_oper_channel(local); + /* We should always be on-channel at this point. */ + WARN_ON(!on_oper_chan2); + if (on_oper_chan2 && (on_oper_chan != on_oper_chan2)) + enable_beacons = true; + + ieee80211_offchannel_return(local, enable_beacons, true); + } + + 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); +} + +void ieee80211_scan_completed(struct ieee80211_hw *hw, bool aborted) +{ + struct ieee80211_local *local = hw_to_local(hw); + + trace_api_scan_completed(local, aborted); + + set_bit(SCAN_COMPLETED, &local->scanning); + if (aborted) + set_bit(SCAN_ABORTED, &local->scanning); + ieee80211_queue_delayed_work(&local->hw, &local->scan_work, 0); +} +EXPORT_SYMBOL(ieee80211_scan_completed); + +static int ieee80211_start_sw_scan(struct ieee80211_local *local) +{ + /* + * Hardware/driver doesn't support hw_scan, so use software + * scanning instead. First send a nullfunc frame with power save + * bit on so that AP will buffer the frames for us while we are not + * listening, then send probe requests to each channel and wait for + * the responses. After all channels are scanned, tune back to the + * original channel and send a nullfunc frame with power save bit + * off to trigger the AP to send us all the buffered frames. + * + * Note that while local->sw_scanning is true everything else but + * nullfunc frames and probe requests will be dropped in + * ieee80211_tx_h_check_assoc(). + */ + drv_sw_scan_start(local); + + local->leave_oper_channel_time = 0; + local->next_scan_state = SCAN_DECISION; + local->scan_channel_idx = 0; + + /* We always want to use off-channel PS, even if we + * are not really leaving oper-channel. Don't + * tell the AP though, as long as we are on-channel. + */ + ieee80211_offchannel_enable_all_ps(local, false); + + ieee80211_configure_filter(local); + + /* We need to set power level at maximum rate for scanning. */ + ieee80211_hw_config(local, 0); + + ieee80211_queue_delayed_work(&local->hw, + &local->scan_work, + IEEE80211_CHANNEL_TIME); + + return 0; +} + + +static int __ieee80211_start_scan(struct ieee80211_sub_if_data *sdata, + struct cfg80211_scan_request *req) +{ + struct ieee80211_local *local = sdata->local; + int rc; + + lockdep_assert_held(&local->mtx); + + 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; + + local->hw_scan_req = kmalloc( + sizeof(*local->hw_scan_req) + + req->n_channels * sizeof(req->channels[0]) + + 2 + IEEE80211_MAX_SSID_LEN + local->scan_ies_len + + req->ie_len, GFP_KERNEL); + if (!local->hw_scan_req) + return -ENOMEM; + + local->hw_scan_req->ssids = req->ssids; + local->hw_scan_req->n_ssids = req->n_ssids; + ies = (u8 *)local->hw_scan_req + + sizeof(*local->hw_scan_req) + + req->n_channels * sizeof(req->channels[0]); + 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 (local->ops->hw_scan) + __set_bit(SCAN_HW_SCANNING, &local->scanning); + else + __set_bit(SCAN_SW_SCANNING, &local->scanning); + + ieee80211_recalc_idle(local); + + if (local->ops->hw_scan) { + WARN_ON(!ieee80211_prep_hw_scan(local)); + rc = drv_hw_scan(local, sdata, local->hw_scan_req); + } else + rc = ieee80211_start_sw_scan(local); + + if (rc) { + kfree(local->hw_scan_req); + local->hw_scan_req = NULL; + local->scanning = 0; + + ieee80211_recalc_idle(local); + + local->scan_req = NULL; + local->scan_sdata = NULL; + } + + 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 void 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; + + /* + * 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 (!ieee80211_sdata_running(sdata)) + continue; + + if (sdata->vif.type == NL80211_IFTYPE_STATION) { + if (sdata->u.mgd.associated) { + associated = true; + + 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; + } + } + } + } + mutex_unlock(&local->iflist_mtx); + + next_chan = local->scan_req->channels[local->scan_channel_idx]; + + if (ieee80211_cfg_on_oper_channel(local)) { + /* We're currently on operating channel. */ + if (next_chan == local->oper_channel) + /* We don't need to move off of operating channel. */ + local->next_scan_state = SCAN_SET_CHANNEL; + else + /* + * We do need to leave operating channel, as next + * scan is somewhere else. + */ + local->next_scan_state = SCAN_LEAVE_OPER_CHANNEL; + } else { + /* + * we're currently scanning a different channel, let's + * 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. + */ + + 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; + } + + *next_delay = 0; +} + +static void ieee80211_scan_state_leave_oper_channel(struct ieee80211_local *local, + unsigned long *next_delay) +{ + /* PS will already be in off-channel mode, + * we do that once at the beginning of scanning. + */ + ieee80211_offchannel_stop_vifs(local, false); + + /* + * What if the nullfunc frames didn't arrive? + */ + drv_flush(local, false); + if (local->ops->flush) + *next_delay = 0; + else + *next_delay = HZ / 10; + + /* remember when we left the operating channel */ + local->leave_oper_channel_time = jiffies; + + /* advance to the next channel to be scanned */ + local->next_scan_state = SCAN_SET_CHANNEL; +} + +static void ieee80211_scan_state_enter_oper_channel(struct ieee80211_local *local, + unsigned long *next_delay) +{ + /* switch back to the operating channel */ + local->scan_channel = NULL; + if (!ieee80211_cfg_on_oper_channel(local)) + ieee80211_hw_config(local, IEEE80211_CONF_CHANGE_CHANNEL); + + /* + * Re-enable vifs and beaconing. Leave PS + * in off-channel state..will put that back + * on-channel at the end of scanning. + */ + ieee80211_offchannel_return(local, true, false); + + *next_delay = HZ / 5; + local->next_scan_state = SCAN_DECISION; +} + +static void ieee80211_scan_state_set_channel(struct ieee80211_local *local, + unsigned long *next_delay) +{ + int skip; + struct ieee80211_channel *chan; + + skip = 0; + chan = local->scan_req->channels[local->scan_channel_idx]; + + local->scan_channel = chan; + + /* Only call hw-config if we really need to change channels. */ + if (chan != local->hw.conf.channel) + if (ieee80211_hw_config(local, IEEE80211_CONF_CHANGE_CHANNEL)) + skip = 1; + + /* 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; + } + + /* + * 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; + local->next_scan_state = SCAN_DECISION; + return; + } + + /* active scan, send probes */ + *next_delay = IEEE80211_PROBE_DELAY; + local->next_scan_state = SCAN_SEND_PROBE; +} + +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->next_scan_state = SCAN_DECISION; +} + +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; + unsigned long next_delay = 0; + bool aborted, hw_scan; + + mutex_lock(&local->mtx); + + sdata = local->scan_sdata; + + if (test_and_clear_bit(SCAN_COMPLETED, &local->scanning)) { + aborted = test_and_clear_bit(SCAN_ABORTED, &local->scanning); + goto out_complete; + } + + if (!sdata || !local->scan_req) + goto out; + + if (local->scan_req && !local->scanning) { + struct cfg80211_scan_request *req = local->scan_req; + int rc; + + local->scan_req = NULL; + local->scan_sdata = NULL; + + rc = __ieee80211_start_scan(sdata, req); + if (rc) { + /* need to complete scan in cfg80211 */ + local->scan_req = req; + aborted = true; + goto out_complete; + } else + goto out; + } + + /* + * Avoid re-scheduling when the sdata is going away. + */ + if (!ieee80211_sdata_running(sdata)) { + aborted = true; + goto out_complete; + } + + /* + * as long as no delay is required advance immediately + * without scheduling a new work + */ + do { + if (!ieee80211_sdata_running(sdata)) { + aborted = true; + goto out_complete; + } + + switch (local->next_scan_state) { + case SCAN_DECISION: + /* if no more bands/channels left, complete scan */ + if (local->scan_channel_idx >= local->scan_req->n_channels) { + aborted = false; + goto out_complete; + } + ieee80211_scan_state_decision(local, &next_delay); + break; + case SCAN_SET_CHANNEL: + ieee80211_scan_state_set_channel(local, &next_delay); + break; + case SCAN_SEND_PROBE: + ieee80211_scan_state_send_probe(local, &next_delay); + break; + case SCAN_LEAVE_OPER_CHANNEL: + ieee80211_scan_state_leave_oper_channel(local, &next_delay); + break; + case SCAN_ENTER_OPER_CHANNEL: + ieee80211_scan_state_enter_oper_channel(local, &next_delay); + break; + } + } while (next_delay == 0); + + ieee80211_queue_delayed_work(&local->hw, &local->scan_work, next_delay); + goto out; + +out_complete: + hw_scan = test_bit(SCAN_HW_SCANNING, &local->scanning); + __ieee80211_scan_completed(&local->hw, aborted, hw_scan); +out: + mutex_unlock(&local->mtx); +} + +int ieee80211_request_scan(struct ieee80211_sub_if_data *sdata, + struct cfg80211_scan_request *req) +{ + int res; + + mutex_lock(&sdata->local->mtx); + res = __ieee80211_start_scan(sdata, req); + mutex_unlock(&sdata->local->mtx); + + return res; +} + +int ieee80211_request_internal_scan(struct ieee80211_sub_if_data *sdata, + const u8 *ssid, u8 ssid_len, + struct ieee80211_channel *chan) +{ + struct ieee80211_local *local = sdata->local; + int ret = -EBUSY; + enum ieee80211_band band; + + mutex_lock(&local->mtx); + + /* busy scanning */ + 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; + + ret = __ieee80211_start_scan(sdata, sdata->local->int_scan_req); + unlock: + mutex_unlock(&local->mtx); + return ret; +} + +/* + * Only call this function when a scan can't be queued -- under RTNL. + */ +void ieee80211_scan_cancel(struct ieee80211_local *local) +{ + bool abortscan; + + /* + * We are only canceling software scan, or deferred scan that was not + * yet really started (see __ieee80211_start_scan ). + * + * Regarding hardware scan: + * - we can not call __ieee80211_scan_completed() as when + * SCAN_HW_SCANNING bit is set this function change + * local->hw_scan_req to operate on 5G band, what race with + * driver which can use local->hw_scan_req + * + * - we can not cancel scan_work since driver can schedule it + * by ieee80211_scan_completed(..., true) to finish scan + * + * Hence low lever driver is responsible for canceling HW scan. + */ + + mutex_lock(&local->mtx); + abortscan = local->scan_req && !test_bit(SCAN_HW_SCANNING, &local->scanning); + if (abortscan) { + /* + * The scan is canceled, but stop work from being pending. + * + * If the work is currently running, it must be blocked on + * the mutex, but we'll set scan_sdata = NULL and it'll + * simply exit once it acquires the mutex. + */ + cancel_delayed_work(&local->scan_work); + /* and clean up */ + __ieee80211_scan_completed(&local->hw, true, false); + } + mutex_unlock(&local->mtx); +} + +int ieee80211_request_sched_scan_start(struct ieee80211_sub_if_data *sdata, + struct cfg80211_sched_scan_request *req) +{ + struct ieee80211_local *local = sdata->local; + int ret, i; + + mutex_lock(&sdata->local->mtx); + + if (local->sched_scanning) { + ret = -EBUSY; + goto out; + } + + if (!local->ops->sched_scan_start) { + ret = -ENOTSUPP; + goto out; + } + + for (i = 0; i < IEEE80211_NUM_BANDS; i++) { + local->sched_scan_ies.ie[i] = kzalloc(2 + + IEEE80211_MAX_SSID_LEN + + local->scan_ies_len + + req->ie_len, + GFP_KERNEL); + if (!local->sched_scan_ies.ie[i]) { + ret = -ENOMEM; + goto out_free; + } + + local->sched_scan_ies.len[i] = + ieee80211_build_preq_ies(local, + local->sched_scan_ies.ie[i], + req->ie, req->ie_len, i, + (u32) -1, 0); + } + + ret = drv_sched_scan_start(local, sdata, req, + &local->sched_scan_ies); + if (ret == 0) { + local->sched_scanning = true; + goto out; + } + +out_free: + while (i > 0) + kfree(local->sched_scan_ies.ie[--i]); +out: + mutex_unlock(&sdata->local->mtx); + return ret; +} + +int ieee80211_request_sched_scan_stop(struct ieee80211_sub_if_data *sdata) +{ + struct ieee80211_local *local = sdata->local; + int ret = 0, i; + + mutex_lock(&sdata->local->mtx); + + if (!local->ops->sched_scan_stop) { + ret = -ENOTSUPP; + goto out; + } + + if (local->sched_scanning) { + for (i = 0; i < IEEE80211_NUM_BANDS; i++) + kfree(local->sched_scan_ies.ie[i]); + + drv_sched_scan_stop(local, sdata); + local->sched_scanning = false; + } +out: + mutex_unlock(&sdata->local->mtx); + + return ret; +} + +void ieee80211_sched_scan_results(struct ieee80211_hw *hw) +{ + struct ieee80211_local *local = hw_to_local(hw); + + trace_api_sched_scan_results(local); + + cfg80211_sched_scan_results(hw->wiphy); +} +EXPORT_SYMBOL(ieee80211_sched_scan_results); + +void ieee80211_sched_scan_stopped_work(struct work_struct *work) +{ + struct ieee80211_local *local = + container_of(work, struct ieee80211_local, + sched_scan_stopped_work); + int i; + + mutex_lock(&local->mtx); + + if (!local->sched_scanning) { + mutex_unlock(&local->mtx); + return; + } + + for (i = 0; i < IEEE80211_NUM_BANDS; i++) + kfree(local->sched_scan_ies.ie[i]); + + local->sched_scanning = false; + + mutex_unlock(&local->mtx); + + cfg80211_sched_scan_stopped(local->hw.wiphy); +} + +void ieee80211_sched_scan_stopped(struct ieee80211_hw *hw) +{ + struct ieee80211_local *local = hw_to_local(hw); + + trace_api_sched_scan_stopped(local); + + ieee80211_queue_work(&local->hw, &local->sched_scan_stopped_work); +} +EXPORT_SYMBOL(ieee80211_sched_scan_stopped); |