mirror of
https://github.com/AuxXxilium/linux_dsm_epyc7002.git
synced 2024-12-05 21:26:39 +07:00
d07bfd8b6f
The scan code has a race that Michael reported he ran into, but it's easy to fix while at the same time simplifying the code. The race resulted in the following warning: ------------[ cut here ]------------ WARNING: at net/mac80211/scan.c:310 ieee80211_rx_bss_free+0x20c/0x4b8 [mac80211]() Modules linked in: [...] [<c0033edc>] (unwind_backtrace+0x0/0xe0) from [<c004f2a4>] (warn_slowpath_common+0x4c/0x64) [... backtrace wasn't useful ...] Reported-by: Michael Buesch <mb@bu3sch.de> Signed-off-by: Johannes Berg <johannes.berg@intel.com> Signed-off-by: John W. Linville <linville@tuxdriver.com>
853 lines
22 KiB
C
853 lines
22 KiB
C
/*
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* Scanning implementation
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*
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* Copyright 2003, Jouni Malinen <jkmaline@cc.hut.fi>
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* Copyright 2004, Instant802 Networks, Inc.
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* Copyright 2005, Devicescape Software, Inc.
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* Copyright 2006-2007 Jiri Benc <jbenc@suse.cz>
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* Copyright 2007, Michael Wu <flamingice@sourmilk.net>
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*
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* This program is free software; you can redistribute it and/or modify
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* it under the terms of the GNU General Public License version 2 as
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* published by the Free Software Foundation.
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*/
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#include <linux/if_arp.h>
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#include <linux/rtnetlink.h>
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#include <linux/pm_qos_params.h>
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#include <net/sch_generic.h>
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#include <linux/slab.h>
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#include <net/mac80211.h>
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#include "ieee80211_i.h"
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#include "driver-ops.h"
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#include "mesh.h"
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#define IEEE80211_PROBE_DELAY (HZ / 33)
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#define IEEE80211_CHANNEL_TIME (HZ / 33)
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#define IEEE80211_PASSIVE_CHANNEL_TIME (HZ / 8)
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struct ieee80211_bss *
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ieee80211_rx_bss_get(struct ieee80211_local *local, u8 *bssid, int freq,
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u8 *ssid, u8 ssid_len)
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{
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struct cfg80211_bss *cbss;
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cbss = cfg80211_get_bss(local->hw.wiphy,
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ieee80211_get_channel(local->hw.wiphy, freq),
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bssid, ssid, ssid_len, 0, 0);
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if (!cbss)
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return NULL;
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return (void *)cbss->priv;
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}
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static void ieee80211_rx_bss_free(struct cfg80211_bss *cbss)
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{
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struct ieee80211_bss *bss = (void *)cbss->priv;
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kfree(bss_mesh_id(bss));
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kfree(bss_mesh_cfg(bss));
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}
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void ieee80211_rx_bss_put(struct ieee80211_local *local,
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struct ieee80211_bss *bss)
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{
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if (!bss)
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return;
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cfg80211_put_bss(container_of((void *)bss, struct cfg80211_bss, priv));
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}
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static bool is_uapsd_supported(struct ieee802_11_elems *elems)
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{
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u8 qos_info;
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if (elems->wmm_info && elems->wmm_info_len == 7
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&& elems->wmm_info[5] == 1)
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qos_info = elems->wmm_info[6];
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else if (elems->wmm_param && elems->wmm_param_len == 24
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&& elems->wmm_param[5] == 1)
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qos_info = elems->wmm_param[6];
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else
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/* no valid wmm information or parameter element found */
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return false;
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return qos_info & IEEE80211_WMM_IE_AP_QOSINFO_UAPSD;
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}
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struct ieee80211_bss *
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ieee80211_bss_info_update(struct ieee80211_local *local,
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struct ieee80211_rx_status *rx_status,
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struct ieee80211_mgmt *mgmt,
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size_t len,
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struct ieee802_11_elems *elems,
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struct ieee80211_channel *channel,
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bool beacon)
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{
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struct cfg80211_bss *cbss;
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struct ieee80211_bss *bss;
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int clen, srlen;
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s32 signal = 0;
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if (local->hw.flags & IEEE80211_HW_SIGNAL_DBM)
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signal = rx_status->signal * 100;
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else if (local->hw.flags & IEEE80211_HW_SIGNAL_UNSPEC)
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signal = (rx_status->signal * 100) / local->hw.max_signal;
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cbss = cfg80211_inform_bss_frame(local->hw.wiphy, channel,
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mgmt, len, signal, GFP_ATOMIC);
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if (!cbss)
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return NULL;
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cbss->free_priv = ieee80211_rx_bss_free;
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bss = (void *)cbss->priv;
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/* save the ERP value so that it is available at association time */
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if (elems->erp_info && elems->erp_info_len >= 1) {
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bss->erp_value = elems->erp_info[0];
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bss->has_erp_value = 1;
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}
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if (elems->tim) {
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struct ieee80211_tim_ie *tim_ie =
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(struct ieee80211_tim_ie *)elems->tim;
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bss->dtim_period = tim_ie->dtim_period;
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}
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/* If the beacon had no TIM IE, or it was invalid, use 1 */
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if (beacon && !bss->dtim_period)
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bss->dtim_period = 1;
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/* replace old supported rates if we get new values */
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srlen = 0;
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if (elems->supp_rates) {
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clen = IEEE80211_MAX_SUPP_RATES;
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if (clen > elems->supp_rates_len)
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clen = elems->supp_rates_len;
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memcpy(bss->supp_rates, elems->supp_rates, clen);
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srlen += clen;
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}
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if (elems->ext_supp_rates) {
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clen = IEEE80211_MAX_SUPP_RATES - srlen;
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if (clen > elems->ext_supp_rates_len)
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clen = elems->ext_supp_rates_len;
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memcpy(bss->supp_rates + srlen, elems->ext_supp_rates, clen);
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srlen += clen;
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}
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if (srlen)
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bss->supp_rates_len = srlen;
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bss->wmm_used = elems->wmm_param || elems->wmm_info;
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bss->uapsd_supported = is_uapsd_supported(elems);
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if (!beacon)
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bss->last_probe_resp = jiffies;
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return bss;
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}
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ieee80211_rx_result
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ieee80211_scan_rx(struct ieee80211_sub_if_data *sdata, struct sk_buff *skb)
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{
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struct ieee80211_rx_status *rx_status = IEEE80211_SKB_RXCB(skb);
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struct ieee80211_mgmt *mgmt;
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struct ieee80211_bss *bss;
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u8 *elements;
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struct ieee80211_channel *channel;
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size_t baselen;
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int freq;
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__le16 fc;
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bool presp, beacon = false;
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struct ieee802_11_elems elems;
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if (skb->len < 2)
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return RX_DROP_UNUSABLE;
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mgmt = (struct ieee80211_mgmt *) skb->data;
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fc = mgmt->frame_control;
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if (ieee80211_is_ctl(fc))
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return RX_CONTINUE;
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if (skb->len < 24)
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return RX_DROP_MONITOR;
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presp = ieee80211_is_probe_resp(fc);
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if (presp) {
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/* ignore ProbeResp to foreign address */
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if (memcmp(mgmt->da, sdata->vif.addr, ETH_ALEN))
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return RX_DROP_MONITOR;
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presp = true;
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elements = mgmt->u.probe_resp.variable;
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baselen = offsetof(struct ieee80211_mgmt, u.probe_resp.variable);
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} else {
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beacon = ieee80211_is_beacon(fc);
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baselen = offsetof(struct ieee80211_mgmt, u.beacon.variable);
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elements = mgmt->u.beacon.variable;
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}
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if (!presp && !beacon)
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return RX_CONTINUE;
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if (baselen > skb->len)
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return RX_DROP_MONITOR;
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ieee802_11_parse_elems(elements, skb->len - baselen, &elems);
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if (elems.ds_params && elems.ds_params_len == 1)
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freq = ieee80211_channel_to_frequency(elems.ds_params[0],
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rx_status->band);
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else
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freq = rx_status->freq;
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channel = ieee80211_get_channel(sdata->local->hw.wiphy, freq);
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if (!channel || channel->flags & IEEE80211_CHAN_DISABLED)
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return RX_DROP_MONITOR;
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bss = ieee80211_bss_info_update(sdata->local, rx_status,
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mgmt, skb->len, &elems,
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channel, beacon);
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if (bss)
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ieee80211_rx_bss_put(sdata->local, bss);
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/* If we are on-operating-channel, and this packet is for the
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* current channel, pass the pkt on up the stack so that
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* the rest of the stack can make use of it.
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*/
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if (ieee80211_cfg_on_oper_channel(sdata->local)
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&& (channel == sdata->local->oper_channel))
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return RX_CONTINUE;
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dev_kfree_skb(skb);
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return RX_QUEUED;
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}
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/* return false if no more work */
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static bool ieee80211_prep_hw_scan(struct ieee80211_local *local)
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{
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struct cfg80211_scan_request *req = local->scan_req;
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enum ieee80211_band band;
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int i, ielen, n_chans;
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do {
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if (local->hw_scan_band == IEEE80211_NUM_BANDS)
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return false;
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band = local->hw_scan_band;
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n_chans = 0;
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for (i = 0; i < req->n_channels; i++) {
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if (req->channels[i]->band == band) {
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local->hw_scan_req->channels[n_chans] =
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req->channels[i];
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n_chans++;
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}
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}
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local->hw_scan_band++;
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} while (!n_chans);
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local->hw_scan_req->n_channels = n_chans;
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ielen = ieee80211_build_preq_ies(local, (u8 *)local->hw_scan_req->ie,
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req->ie, req->ie_len, band, (u32) -1,
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0);
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local->hw_scan_req->ie_len = ielen;
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return true;
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}
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static void __ieee80211_scan_completed(struct ieee80211_hw *hw, bool aborted,
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bool was_hw_scan)
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{
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struct ieee80211_local *local = hw_to_local(hw);
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bool on_oper_chan;
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bool enable_beacons = false;
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lockdep_assert_held(&local->mtx);
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/*
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* It's ok to abort a not-yet-running scan (that
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* we have one at all will be verified by checking
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* local->scan_req next), but not to complete it
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* successfully.
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*/
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if (WARN_ON(!local->scanning && !aborted))
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aborted = true;
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if (WARN_ON(!local->scan_req))
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return;
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if (was_hw_scan && !aborted && ieee80211_prep_hw_scan(local)) {
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int rc = drv_hw_scan(local, local->scan_sdata, local->hw_scan_req);
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if (rc == 0)
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return;
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}
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kfree(local->hw_scan_req);
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local->hw_scan_req = NULL;
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if (local->scan_req != local->int_scan_req)
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cfg80211_scan_done(local->scan_req, aborted);
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local->scan_req = NULL;
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local->scan_sdata = NULL;
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local->scanning = 0;
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local->scan_channel = NULL;
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on_oper_chan = ieee80211_cfg_on_oper_channel(local);
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if (was_hw_scan || !on_oper_chan)
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ieee80211_hw_config(local, IEEE80211_CONF_CHANGE_CHANNEL);
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else
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/* Set power back to normal operating levels. */
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ieee80211_hw_config(local, 0);
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if (!was_hw_scan) {
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bool on_oper_chan2;
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ieee80211_configure_filter(local);
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drv_sw_scan_complete(local);
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on_oper_chan2 = ieee80211_cfg_on_oper_channel(local);
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/* We should always be on-channel at this point. */
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WARN_ON(!on_oper_chan2);
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if (on_oper_chan2 && (on_oper_chan != on_oper_chan2))
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enable_beacons = true;
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ieee80211_offchannel_return(local, enable_beacons, true);
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}
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ieee80211_recalc_idle(local);
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ieee80211_mlme_notify_scan_completed(local);
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ieee80211_ibss_notify_scan_completed(local);
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ieee80211_mesh_notify_scan_completed(local);
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ieee80211_queue_work(&local->hw, &local->work_work);
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}
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void ieee80211_scan_completed(struct ieee80211_hw *hw, bool aborted)
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{
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struct ieee80211_local *local = hw_to_local(hw);
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trace_api_scan_completed(local, aborted);
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set_bit(SCAN_COMPLETED, &local->scanning);
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if (aborted)
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set_bit(SCAN_ABORTED, &local->scanning);
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ieee80211_queue_delayed_work(&local->hw, &local->scan_work, 0);
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}
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EXPORT_SYMBOL(ieee80211_scan_completed);
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static int ieee80211_start_sw_scan(struct ieee80211_local *local)
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{
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/*
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* Hardware/driver doesn't support hw_scan, so use software
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* scanning instead. First send a nullfunc frame with power save
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* bit on so that AP will buffer the frames for us while we are not
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* listening, then send probe requests to each channel and wait for
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* the responses. After all channels are scanned, tune back to the
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* original channel and send a nullfunc frame with power save bit
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* off to trigger the AP to send us all the buffered frames.
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*
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* Note that while local->sw_scanning is true everything else but
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* nullfunc frames and probe requests will be dropped in
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* ieee80211_tx_h_check_assoc().
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*/
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drv_sw_scan_start(local);
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local->leave_oper_channel_time = 0;
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local->next_scan_state = SCAN_DECISION;
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local->scan_channel_idx = 0;
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/* We always want to use off-channel PS, even if we
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* are not really leaving oper-channel. Don't
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* tell the AP though, as long as we are on-channel.
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*/
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ieee80211_offchannel_enable_all_ps(local, false);
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ieee80211_configure_filter(local);
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/* We need to set power level at maximum rate for scanning. */
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ieee80211_hw_config(local, 0);
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ieee80211_queue_delayed_work(&local->hw,
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&local->scan_work,
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IEEE80211_CHANNEL_TIME);
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return 0;
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}
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static int __ieee80211_start_scan(struct ieee80211_sub_if_data *sdata,
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struct cfg80211_scan_request *req)
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{
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struct ieee80211_local *local = sdata->local;
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int rc;
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lockdep_assert_held(&local->mtx);
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if (local->scan_req)
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return -EBUSY;
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if (!list_empty(&local->work_list)) {
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/* wait for the work to finish/time out */
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local->scan_req = req;
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local->scan_sdata = sdata;
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return 0;
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}
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if (local->ops->hw_scan) {
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u8 *ies;
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local->hw_scan_req = kmalloc(
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sizeof(*local->hw_scan_req) +
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req->n_channels * sizeof(req->channels[0]) +
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2 + IEEE80211_MAX_SSID_LEN + local->scan_ies_len +
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req->ie_len, GFP_KERNEL);
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if (!local->hw_scan_req)
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return -ENOMEM;
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local->hw_scan_req->ssids = req->ssids;
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local->hw_scan_req->n_ssids = req->n_ssids;
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ies = (u8 *)local->hw_scan_req +
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sizeof(*local->hw_scan_req) +
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req->n_channels * sizeof(req->channels[0]);
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local->hw_scan_req->ie = ies;
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local->hw_scan_band = 0;
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/*
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* After allocating local->hw_scan_req, we must
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* go through until ieee80211_prep_hw_scan(), so
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* anything that might be changed here and leave
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* this function early must not go after this
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* allocation.
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*/
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}
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local->scan_req = req;
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local->scan_sdata = sdata;
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if (local->ops->hw_scan)
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__set_bit(SCAN_HW_SCANNING, &local->scanning);
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else
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__set_bit(SCAN_SW_SCANNING, &local->scanning);
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ieee80211_recalc_idle(local);
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if (local->ops->hw_scan) {
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WARN_ON(!ieee80211_prep_hw_scan(local));
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rc = drv_hw_scan(local, sdata, local->hw_scan_req);
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} else
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rc = ieee80211_start_sw_scan(local);
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if (rc) {
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kfree(local->hw_scan_req);
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local->hw_scan_req = NULL;
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local->scanning = 0;
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ieee80211_recalc_idle(local);
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local->scan_req = NULL;
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local->scan_sdata = NULL;
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}
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return rc;
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}
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static unsigned long
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ieee80211_scan_get_channel_time(struct ieee80211_channel *chan)
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{
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/*
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* TODO: channel switching also consumes quite some time,
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* add that delay as well to get a better estimation
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*/
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if (chan->flags & IEEE80211_CHAN_PASSIVE_SCAN)
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return IEEE80211_PASSIVE_CHANNEL_TIME;
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return IEEE80211_PROBE_DELAY + IEEE80211_CHANNEL_TIME;
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}
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static void ieee80211_scan_state_decision(struct ieee80211_local *local,
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unsigned long *next_delay)
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{
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bool associated = false;
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bool tx_empty = true;
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bool bad_latency;
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bool listen_int_exceeded;
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unsigned long min_beacon_int = 0;
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struct ieee80211_sub_if_data *sdata;
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struct ieee80211_channel *next_chan;
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/*
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* check if at least one STA interface is associated,
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* 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 {
|
|
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);
|
|
}
|