mac80211: start moving scan code from mlme
authorJohannes Berg <johannes@sipsolutions.net>
Mon, 8 Sep 2008 15:44:25 +0000 (17:44 +0200)
committerJohn W. Linville <linville@tuxdriver.com>
Thu, 11 Sep 2008 19:53:36 +0000 (15:53 -0400)
Here's a first patch to move some code from mlme.c to a
new file called scan.c. The end result will hopefully be
a more manageable mlme.c.

Signed-off-by: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
net/mac80211/Makefile
net/mac80211/ieee80211_i.h
net/mac80211/mlme.c
net/mac80211/scan.c [new file with mode: 0644]

index a169b02..376280a 100644 (file)
@@ -7,6 +7,7 @@ mac80211-y := \
        sta_info.o \
        wep.o \
        wpa.o \
+       scan.o \
        mlme.o \
        iface.o \
        rate.o \
index a33bbd1..25dccd5 100644 (file)
@@ -53,6 +53,12 @@ struct ieee80211_local;
  * increased memory use (about 2 kB of RAM per entry). */
 #define IEEE80211_FRAGMENT_MAX 4
 
+/*
+ * Time after which we ignore scan results and no longer report/use
+ * them in any way.
+ */
+#define IEEE80211_SCAN_RESULT_EXPIRE (10 * HZ)
+
 struct ieee80211_fragment_entry {
        unsigned long first_frag_time;
        unsigned int seq;
@@ -924,8 +930,13 @@ u64 ieee80211_sta_get_rates(struct ieee80211_local *local,
                            enum ieee80211_band band);
 void ieee80211_sta_tx(struct ieee80211_sub_if_data *sdata, struct sk_buff *skb,
                int encrypt);
+void ieee80211_send_probe_req(struct ieee80211_sub_if_data *sdata, u8 *dst,
+                             u8 *ssid, size_t ssid_len);
 void ieee802_11_parse_elems(u8 *start, size_t len,
-                                  struct ieee802_11_elems *elems);
+                           struct ieee802_11_elems *elems);
+void ieee80211_mlme_notify_scan_completed(struct ieee80211_local *local);
+int ieee80211_sta_start_scan(struct ieee80211_sub_if_data *scan_sdata,
+                            u8 *ssid, size_t ssid_len);
 
 #ifdef CONFIG_MAC80211_MESH
 void ieee80211_start_mesh(struct ieee80211_sub_if_data *sdata);
index ba502ce..2caea97 100644 (file)
 #define IEEE80211_SCAN_INTERVAL_SLOW (15 * HZ)
 #define IEEE80211_IBSS_JOIN_TIMEOUT (7 * HZ)
 
-#define IEEE80211_PROBE_DELAY (HZ / 33)
-#define IEEE80211_CHANNEL_TIME (HZ / 33)
-#define IEEE80211_PASSIVE_CHANNEL_TIME (HZ / 5)
-#define IEEE80211_SCAN_RESULT_EXPIRE (10 * HZ)
 #define IEEE80211_IBSS_MERGE_INTERVAL (30 * HZ)
 #define IEEE80211_IBSS_INACTIVITY_LIMIT (60 * HZ)
 #define IEEE80211_MESH_PEER_INACTIVITY_LIMIT (1800 * HZ)
@@ -341,8 +337,8 @@ static void ieee80211_send_auth(struct ieee80211_sub_if_data *sdata,
        ieee80211_sta_tx(sdata, skb, encrypt);
 }
 
-static void ieee80211_send_probe_req(struct ieee80211_sub_if_data *sdata, u8 *dst,
-                                    u8 *ssid, size_t ssid_len)
+void ieee80211_send_probe_req(struct ieee80211_sub_if_data *sdata, u8 *dst,
+                             u8 *ssid, size_t ssid_len)
 {
        struct ieee80211_local *local = sdata->local;
        struct ieee80211_supported_band *sband;
@@ -3466,543 +3462,6 @@ int ieee80211_sta_set_bssid(struct ieee80211_sub_if_data *sdata, u8 *bssid)
 }
 
 
-static void ieee80211_send_nullfunc(struct ieee80211_local *local,
-                                   struct ieee80211_sub_if_data *sdata,
-                                   int powersave)
-{
-       struct sk_buff *skb;
-       struct ieee80211_hdr *nullfunc;
-       __le16 fc;
-
-       skb = dev_alloc_skb(local->hw.extra_tx_headroom + 24);
-       if (!skb) {
-               printk(KERN_DEBUG "%s: failed to allocate buffer for nullfunc "
-                      "frame\n", sdata->dev->name);
-               return;
-       }
-       skb_reserve(skb, local->hw.extra_tx_headroom);
-
-       nullfunc = (struct ieee80211_hdr *) skb_put(skb, 24);
-       memset(nullfunc, 0, 24);
-       fc = cpu_to_le16(IEEE80211_FTYPE_DATA | IEEE80211_STYPE_NULLFUNC |
-                        IEEE80211_FCTL_TODS);
-       if (powersave)
-               fc |= cpu_to_le16(IEEE80211_FCTL_PM);
-       nullfunc->frame_control = fc;
-       memcpy(nullfunc->addr1, sdata->u.sta.bssid, ETH_ALEN);
-       memcpy(nullfunc->addr2, sdata->dev->dev_addr, ETH_ALEN);
-       memcpy(nullfunc->addr3, sdata->u.sta.bssid, ETH_ALEN);
-
-       ieee80211_sta_tx(sdata, skb, 0);
-}
-
-
-static void ieee80211_restart_sta_timer(struct ieee80211_sub_if_data *sdata)
-{
-       if (sdata->vif.type == IEEE80211_IF_TYPE_STA ||
-           ieee80211_vif_is_mesh(&sdata->vif))
-               ieee80211_sta_timer((unsigned long)sdata);
-}
-
-void ieee80211_scan_completed(struct ieee80211_hw *hw)
-{
-       struct ieee80211_local *local = hw_to_local(hw);
-       struct ieee80211_sub_if_data *sdata;
-       union iwreq_data wrqu;
-
-       local->last_scan_completed = jiffies;
-       memset(&wrqu, 0, sizeof(wrqu));
-       wireless_send_event(local->scan_sdata->dev, SIOCGIWSCAN, &wrqu, NULL);
-
-       if (local->sta_hw_scanning) {
-               local->sta_hw_scanning = 0;
-               if (ieee80211_hw_config(local))
-                       printk(KERN_DEBUG "%s: failed to restore operational "
-                              "channel after scan\n", wiphy_name(local->hw.wiphy));
-               /* Restart STA timer for HW scan case */
-               rcu_read_lock();
-               list_for_each_entry_rcu(sdata, &local->interfaces, list)
-                       ieee80211_restart_sta_timer(sdata);
-               rcu_read_unlock();
-
-               goto done;
-       }
-
-       local->sta_sw_scanning = 0;
-       if (ieee80211_hw_config(local))
-               printk(KERN_DEBUG "%s: failed to restore operational "
-                      "channel after scan\n", wiphy_name(local->hw.wiphy));
-
-
-       netif_tx_lock_bh(local->mdev);
-       netif_addr_lock(local->mdev);
-       local->filter_flags &= ~FIF_BCN_PRBRESP_PROMISC;
-       local->ops->configure_filter(local_to_hw(local),
-                                    FIF_BCN_PRBRESP_PROMISC,
-                                    &local->filter_flags,
-                                    local->mdev->mc_count,
-                                    local->mdev->mc_list);
-
-       netif_addr_unlock(local->mdev);
-       netif_tx_unlock_bh(local->mdev);
-
-       rcu_read_lock();
-       list_for_each_entry_rcu(sdata, &local->interfaces, list) {
-               /* Tell AP we're back */
-               if (sdata->vif.type == IEEE80211_IF_TYPE_STA) {
-                       if (sdata->u.sta.flags & IEEE80211_STA_ASSOCIATED) {
-                               ieee80211_send_nullfunc(local, sdata, 0);
-                               netif_tx_wake_all_queues(sdata->dev);
-                       }
-               } else
-                       netif_tx_wake_all_queues(sdata->dev);
-
-               ieee80211_restart_sta_timer(sdata);
-       }
-       rcu_read_unlock();
-
- done:
-       sdata = local->scan_sdata;
-       if (sdata->vif.type == IEEE80211_IF_TYPE_IBSS) {
-               struct ieee80211_if_sta *ifsta = &sdata->u.sta;
-               if (!(ifsta->flags & IEEE80211_STA_BSSID_SET) ||
-                   (!(ifsta->state == IEEE80211_STA_MLME_IBSS_JOINED) &&
-                   !ieee80211_sta_active_ibss(sdata)))
-                       ieee80211_sta_find_ibss(sdata, ifsta);
-       }
-}
-EXPORT_SYMBOL(ieee80211_scan_completed);
-
-void ieee80211_sta_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 = local->scan_sdata;
-       struct ieee80211_supported_band *sband;
-       struct ieee80211_channel *chan;
-       int skip;
-       unsigned long next_delay = 0;
-
-       if (!local->sta_sw_scanning)
-               return;
-
-       switch (local->scan_state) {
-       case SCAN_SET_CHANNEL:
-               /*
-                * Get current scan band. scan_band may be IEEE80211_NUM_BANDS
-                * after we successfully scanned the last channel of the last
-                * band (and the last band is supported by the hw)
-                */
-               if (local->scan_band < IEEE80211_NUM_BANDS)
-                       sband = local->hw.wiphy->bands[local->scan_band];
-               else
-                       sband = NULL;
-
-               /*
-                * If we are at an unsupported band and have more bands
-                * left to scan, advance to the next supported one.
-                */
-               while (!sband && local->scan_band < IEEE80211_NUM_BANDS - 1) {
-                       local->scan_band++;
-                       sband = local->hw.wiphy->bands[local->scan_band];
-                       local->scan_channel_idx = 0;
-               }
-
-               /* if no more bands/channels left, complete scan */
-               if (!sband || local->scan_channel_idx >= sband->n_channels) {
-                       ieee80211_scan_completed(local_to_hw(local));
-                       return;
-               }
-               skip = 0;
-               chan = &sband->channels[local->scan_channel_idx];
-
-               if (chan->flags & IEEE80211_CHAN_DISABLED ||
-                   (sdata->vif.type == IEEE80211_IF_TYPE_IBSS &&
-                    chan->flags & IEEE80211_CHAN_NO_IBSS))
-                       skip = 1;
-
-               if (!skip) {
-                       local->scan_channel = chan;
-                       if (ieee80211_hw_config(local)) {
-                               printk(KERN_DEBUG "%s: failed to set freq to "
-                                      "%d MHz for scan\n", wiphy_name(local->hw.wiphy),
-                                      chan->center_freq);
-                               skip = 1;
-                       }
-               }
-
-               /* advance state machine to next channel/band */
-               local->scan_channel_idx++;
-               if (local->scan_channel_idx >= sband->n_channels) {
-                       /*
-                        * scan_band may end up == IEEE80211_NUM_BANDS, but
-                        * we'll catch that case above and complete the scan
-                        * if that is the case.
-                        */
-                       local->scan_band++;
-                       local->scan_channel_idx = 0;
-               }
-
-               if (skip)
-                       break;
-
-               next_delay = IEEE80211_PROBE_DELAY +
-                            usecs_to_jiffies(local->hw.channel_change_time);
-               local->scan_state = SCAN_SEND_PROBE;
-               break;
-       case SCAN_SEND_PROBE:
-               next_delay = IEEE80211_PASSIVE_CHANNEL_TIME;
-               local->scan_state = SCAN_SET_CHANNEL;
-
-               if (local->scan_channel->flags & IEEE80211_CHAN_PASSIVE_SCAN)
-                       break;
-               ieee80211_send_probe_req(sdata, NULL, local->scan_ssid,
-                                        local->scan_ssid_len);
-               next_delay = IEEE80211_CHANNEL_TIME;
-               break;
-       }
-
-       if (local->sta_sw_scanning)
-               queue_delayed_work(local->hw.workqueue, &local->scan_work,
-                                  next_delay);
-}
-
-
-static int ieee80211_sta_start_scan(struct ieee80211_sub_if_data *scan_sdata,
-                                   u8 *ssid, size_t ssid_len)
-{
-       struct ieee80211_local *local = scan_sdata->local;
-       struct ieee80211_sub_if_data *sdata;
-
-       if (ssid_len > IEEE80211_MAX_SSID_LEN)
-               return -EINVAL;
-
-       /* MLME-SCAN.request (page 118)  page 144 (11.1.3.1)
-        * BSSType: INFRASTRUCTURE, INDEPENDENT, ANY_BSS
-        * BSSID: MACAddress
-        * SSID
-        * ScanType: ACTIVE, PASSIVE
-        * ProbeDelay: delay (in microseconds) to be used prior to transmitting
-        *    a Probe frame during active scanning
-        * ChannelList
-        * MinChannelTime (>= ProbeDelay), in TU
-        * MaxChannelTime: (>= MinChannelTime), in TU
-        */
-
-        /* MLME-SCAN.confirm
-         * BSSDescriptionSet
-         * ResultCode: SUCCESS, INVALID_PARAMETERS
-        */
-
-       if (local->sta_sw_scanning || local->sta_hw_scanning) {
-               if (local->scan_sdata == scan_sdata)
-                       return 0;
-               return -EBUSY;
-       }
-
-       if (local->ops->hw_scan) {
-               int rc = local->ops->hw_scan(local_to_hw(local),
-                                            ssid, ssid_len);
-               if (!rc) {
-                       local->sta_hw_scanning = 1;
-                       local->scan_sdata = scan_sdata;
-               }
-               return rc;
-       }
-
-       local->sta_sw_scanning = 1;
-
-       rcu_read_lock();
-       list_for_each_entry_rcu(sdata, &local->interfaces, list) {
-               if (sdata->vif.type == IEEE80211_IF_TYPE_STA) {
-                       if (sdata->u.sta.flags & IEEE80211_STA_ASSOCIATED) {
-                               netif_tx_stop_all_queues(sdata->dev);
-                               ieee80211_send_nullfunc(local, sdata, 1);
-                       }
-               } else
-                       netif_tx_stop_all_queues(sdata->dev);
-       }
-       rcu_read_unlock();
-
-       if (ssid) {
-               local->scan_ssid_len = ssid_len;
-               memcpy(local->scan_ssid, ssid, ssid_len);
-       } else
-               local->scan_ssid_len = 0;
-       local->scan_state = SCAN_SET_CHANNEL;
-       local->scan_channel_idx = 0;
-       local->scan_band = IEEE80211_BAND_2GHZ;
-       local->scan_sdata = scan_sdata;
-
-       netif_addr_lock_bh(local->mdev);
-       local->filter_flags |= FIF_BCN_PRBRESP_PROMISC;
-       local->ops->configure_filter(local_to_hw(local),
-                                    FIF_BCN_PRBRESP_PROMISC,
-                                    &local->filter_flags,
-                                    local->mdev->mc_count,
-                                    local->mdev->mc_list);
-       netif_addr_unlock_bh(local->mdev);
-
-       /* TODO: start scan as soon as all nullfunc frames are ACKed */
-       queue_delayed_work(local->hw.workqueue, &local->scan_work,
-                          IEEE80211_CHANNEL_TIME);
-
-       return 0;
-}
-
-
-int ieee80211_sta_req_scan(struct ieee80211_sub_if_data *sdata, u8 *ssid, size_t ssid_len)
-{
-       struct ieee80211_if_sta *ifsta = &sdata->u.sta;
-       struct ieee80211_local *local = sdata->local;
-
-       if (sdata->vif.type != IEEE80211_IF_TYPE_STA)
-               return ieee80211_sta_start_scan(sdata, ssid, ssid_len);
-
-       if (local->sta_sw_scanning || local->sta_hw_scanning) {
-               if (local->scan_sdata == sdata)
-                       return 0;
-               return -EBUSY;
-       }
-
-       ifsta->scan_ssid_len = ssid_len;
-       if (ssid_len)
-               memcpy(ifsta->scan_ssid, ssid, ssid_len);
-       set_bit(IEEE80211_STA_REQ_SCAN, &ifsta->request);
-       queue_work(local->hw.workqueue, &ifsta->work);
-       return 0;
-}
-
-
-static void ieee80211_sta_add_scan_ies(struct iw_request_info *info,
-                                      struct ieee80211_sta_bss *bss,
-                                      char **current_ev, char *end_buf)
-{
-       u8 *pos, *end, *next;
-       struct iw_event iwe;
-
-       if (bss == NULL || bss->ies == NULL)
-               return;
-
-       /*
-        * If needed, fragment the IEs buffer (at IE boundaries) into short
-        * enough fragments to fit into IW_GENERIC_IE_MAX octet messages.
-        */
-       pos = bss->ies;
-       end = pos + bss->ies_len;
-
-       while (end - pos > IW_GENERIC_IE_MAX) {
-               next = pos + 2 + pos[1];
-               while (next + 2 + next[1] - pos < IW_GENERIC_IE_MAX)
-                       next = next + 2 + next[1];
-
-               memset(&iwe, 0, sizeof(iwe));
-               iwe.cmd = IWEVGENIE;
-               iwe.u.data.length = next - pos;
-               *current_ev = iwe_stream_add_point(info, *current_ev,
-                                                  end_buf, &iwe, pos);
-
-               pos = next;
-       }
-
-       if (end > pos) {
-               memset(&iwe, 0, sizeof(iwe));
-               iwe.cmd = IWEVGENIE;
-               iwe.u.data.length = end - pos;
-               *current_ev = iwe_stream_add_point(info, *current_ev,
-                                                  end_buf, &iwe, pos);
-       }
-}
-
-
-static char *
-ieee80211_sta_scan_result(struct ieee80211_local *local,
-                         struct iw_request_info *info,
-                         struct ieee80211_sta_bss *bss,
-                         char *current_ev, char *end_buf)
-{
-       struct iw_event iwe;
-       char *buf;
-
-       if (time_after(jiffies,
-                      bss->last_update + IEEE80211_SCAN_RESULT_EXPIRE))
-               return current_ev;
-
-       memset(&iwe, 0, sizeof(iwe));
-       iwe.cmd = SIOCGIWAP;
-       iwe.u.ap_addr.sa_family = ARPHRD_ETHER;
-       memcpy(iwe.u.ap_addr.sa_data, bss->bssid, ETH_ALEN);
-       current_ev = iwe_stream_add_event(info, current_ev, end_buf, &iwe,
-                                         IW_EV_ADDR_LEN);
-
-       memset(&iwe, 0, sizeof(iwe));
-       iwe.cmd = SIOCGIWESSID;
-       if (bss_mesh_cfg(bss)) {
-               iwe.u.data.length = bss_mesh_id_len(bss);
-               iwe.u.data.flags = 1;
-               current_ev = iwe_stream_add_point(info, current_ev, end_buf,
-                                                 &iwe, bss_mesh_id(bss));
-       } else {
-               iwe.u.data.length = bss->ssid_len;
-               iwe.u.data.flags = 1;
-               current_ev = iwe_stream_add_point(info, current_ev, end_buf,
-                                                 &iwe, bss->ssid);
-       }
-
-       if (bss->capability & (WLAN_CAPABILITY_ESS | WLAN_CAPABILITY_IBSS)
-           || bss_mesh_cfg(bss)) {
-               memset(&iwe, 0, sizeof(iwe));
-               iwe.cmd = SIOCGIWMODE;
-               if (bss_mesh_cfg(bss))
-                       iwe.u.mode = IW_MODE_MESH;
-               else if (bss->capability & WLAN_CAPABILITY_ESS)
-                       iwe.u.mode = IW_MODE_MASTER;
-               else
-                       iwe.u.mode = IW_MODE_ADHOC;
-               current_ev = iwe_stream_add_event(info, current_ev, end_buf,
-                                                 &iwe, IW_EV_UINT_LEN);
-       }
-
-       memset(&iwe, 0, sizeof(iwe));
-       iwe.cmd = SIOCGIWFREQ;
-       iwe.u.freq.m = ieee80211_frequency_to_channel(bss->freq);
-       iwe.u.freq.e = 0;
-       current_ev = iwe_stream_add_event(info, current_ev, end_buf, &iwe,
-                                         IW_EV_FREQ_LEN);
-
-       memset(&iwe, 0, sizeof(iwe));
-       iwe.cmd = SIOCGIWFREQ;
-       iwe.u.freq.m = bss->freq;
-       iwe.u.freq.e = 6;
-       current_ev = iwe_stream_add_event(info, current_ev, end_buf, &iwe,
-                                         IW_EV_FREQ_LEN);
-       memset(&iwe, 0, sizeof(iwe));
-       iwe.cmd = IWEVQUAL;
-       iwe.u.qual.qual = bss->qual;
-       iwe.u.qual.level = bss->signal;
-       iwe.u.qual.noise = bss->noise;
-       iwe.u.qual.updated = local->wstats_flags;
-       current_ev = iwe_stream_add_event(info, current_ev, end_buf, &iwe,
-                                         IW_EV_QUAL_LEN);
-
-       memset(&iwe, 0, sizeof(iwe));
-       iwe.cmd = SIOCGIWENCODE;
-       if (bss->capability & WLAN_CAPABILITY_PRIVACY)
-               iwe.u.data.flags = IW_ENCODE_ENABLED | IW_ENCODE_NOKEY;
-       else
-               iwe.u.data.flags = IW_ENCODE_DISABLED;
-       iwe.u.data.length = 0;
-       current_ev = iwe_stream_add_point(info, current_ev, end_buf,
-                                         &iwe, "");
-
-       ieee80211_sta_add_scan_ies(info, bss, &current_ev, end_buf);
-
-       if (bss->supp_rates_len > 0) {
-               /* display all supported rates in readable format */
-               char *p = current_ev + iwe_stream_lcp_len(info);
-               int i;
-
-               memset(&iwe, 0, sizeof(iwe));
-               iwe.cmd = SIOCGIWRATE;
-               /* Those two flags are ignored... */
-               iwe.u.bitrate.fixed = iwe.u.bitrate.disabled = 0;
-
-               for (i = 0; i < bss->supp_rates_len; i++) {
-                       iwe.u.bitrate.value = ((bss->supp_rates[i] &
-                                                       0x7f) * 500000);
-                       p = iwe_stream_add_value(info, current_ev, p,
-                                       end_buf, &iwe, IW_EV_PARAM_LEN);
-               }
-               current_ev = p;
-       }
-
-       buf = kmalloc(30, GFP_ATOMIC);
-       if (buf) {
-               memset(&iwe, 0, sizeof(iwe));
-               iwe.cmd = IWEVCUSTOM;
-               sprintf(buf, "tsf=%016llx", (unsigned long long)(bss->timestamp));
-               iwe.u.data.length = strlen(buf);
-               current_ev = iwe_stream_add_point(info, current_ev, end_buf,
-                                                 &iwe, buf);
-               memset(&iwe, 0, sizeof(iwe));
-               iwe.cmd = IWEVCUSTOM;
-               sprintf(buf, " Last beacon: %dms ago",
-                       jiffies_to_msecs(jiffies - bss->last_update));
-               iwe.u.data.length = strlen(buf);
-               current_ev = iwe_stream_add_point(info, current_ev,
-                                                 end_buf, &iwe, buf);
-               kfree(buf);
-       }
-
-       if (bss_mesh_cfg(bss)) {
-               u8 *cfg = bss_mesh_cfg(bss);
-               buf = kmalloc(50, GFP_ATOMIC);
-               if (buf) {
-                       memset(&iwe, 0, sizeof(iwe));
-                       iwe.cmd = IWEVCUSTOM;
-                       sprintf(buf, "Mesh network (version %d)", cfg[0]);
-                       iwe.u.data.length = strlen(buf);
-                       current_ev = iwe_stream_add_point(info, current_ev,
-                                                         end_buf,
-                                                         &iwe, buf);
-                       sprintf(buf, "Path Selection Protocol ID: "
-                               "0x%02X%02X%02X%02X", cfg[1], cfg[2], cfg[3],
-                                                       cfg[4]);
-                       iwe.u.data.length = strlen(buf);
-                       current_ev = iwe_stream_add_point(info, current_ev,
-                                                         end_buf,
-                                                         &iwe, buf);
-                       sprintf(buf, "Path Selection Metric ID: "
-                               "0x%02X%02X%02X%02X", cfg[5], cfg[6], cfg[7],
-                                                       cfg[8]);
-                       iwe.u.data.length = strlen(buf);
-                       current_ev = iwe_stream_add_point(info, current_ev,
-                                                         end_buf,
-                                                         &iwe, buf);
-                       sprintf(buf, "Congestion Control Mode ID: "
-                               "0x%02X%02X%02X%02X", cfg[9], cfg[10],
-                                                       cfg[11], cfg[12]);
-                       iwe.u.data.length = strlen(buf);
-                       current_ev = iwe_stream_add_point(info, current_ev,
-                                                         end_buf,
-                                                         &iwe, buf);
-                       sprintf(buf, "Channel Precedence: "
-                               "0x%02X%02X%02X%02X", cfg[13], cfg[14],
-                                                       cfg[15], cfg[16]);
-                       iwe.u.data.length = strlen(buf);
-                       current_ev = iwe_stream_add_point(info, current_ev,
-                                                         end_buf,
-                                                         &iwe, buf);
-                       kfree(buf);
-               }
-       }
-
-       return current_ev;
-}
-
-
-int ieee80211_sta_scan_results(struct ieee80211_local *local,
-                              struct iw_request_info *info,
-                              char *buf, size_t len)
-{
-       char *current_ev = buf;
-       char *end_buf = buf + len;
-       struct ieee80211_sta_bss *bss;
-
-       spin_lock_bh(&local->sta_bss_lock);
-       list_for_each_entry(bss, &local->sta_bss_list, list) {
-               if (buf + len - current_ev <= IW_EV_ADDR_LEN) {
-                       spin_unlock_bh(&local->sta_bss_lock);
-                       return -E2BIG;
-               }
-               current_ev = ieee80211_sta_scan_result(local, info, bss,
-                                                      current_ev, end_buf);
-       }
-       spin_unlock_bh(&local->sta_bss_lock);
-       return current_ev - buf;
-}
-
-
 int ieee80211_sta_set_extra_ie(struct ieee80211_sub_if_data *sdata, char *ie, size_t len)
 {
        struct ieee80211_if_sta *ifsta = &sdata->u.sta;
@@ -4290,3 +3749,17 @@ void ieee80211_sta_work(struct work_struct *work)
                                        WLAN_REASON_UNSPECIFIED);
        }
 }
+
+void ieee80211_mlme_notify_scan_completed(struct ieee80211_local *local)
+{
+       struct ieee80211_sub_if_data *sdata = local->scan_sdata;
+       struct ieee80211_if_sta *ifsta;
+
+       if (sdata->vif.type == IEEE80211_IF_TYPE_IBSS) {
+               ifsta = &sdata->u.sta;
+               if (!(ifsta->flags & IEEE80211_STA_BSSID_SET) ||
+                   (!(ifsta->state == IEEE80211_STA_MLME_IBSS_JOINED) &&
+                   !ieee80211_sta_active_ibss(sdata)))
+                       ieee80211_sta_find_ibss(sdata, ifsta);
+       }
+}
diff --git a/net/mac80211/scan.c b/net/mac80211/scan.c
new file mode 100644 (file)
index 0000000..68fa782
--- /dev/null
@@ -0,0 +1,553 @@
+/*
+ * BSS client mode 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/wireless.h>
+#include <linux/if_arp.h>
+#include <net/mac80211.h>
+#include <net/iw_handler.h>
+
+#include "ieee80211_i.h"
+
+#define IEEE80211_PROBE_DELAY (HZ / 33)
+#define IEEE80211_CHANNEL_TIME (HZ / 33)
+#define IEEE80211_PASSIVE_CHANNEL_TIME (HZ / 5)
+
+
+static void ieee80211_send_nullfunc(struct ieee80211_local *local,
+                                   struct ieee80211_sub_if_data *sdata,
+                                   int powersave)
+{
+       struct sk_buff *skb;
+       struct ieee80211_hdr *nullfunc;
+       __le16 fc;
+
+       skb = dev_alloc_skb(local->hw.extra_tx_headroom + 24);
+       if (!skb) {
+               printk(KERN_DEBUG "%s: failed to allocate buffer for nullfunc "
+                      "frame\n", sdata->dev->name);
+               return;
+       }
+       skb_reserve(skb, local->hw.extra_tx_headroom);
+
+       nullfunc = (struct ieee80211_hdr *) skb_put(skb, 24);
+       memset(nullfunc, 0, 24);
+       fc = cpu_to_le16(IEEE80211_FTYPE_DATA | IEEE80211_STYPE_NULLFUNC |
+                        IEEE80211_FCTL_TODS);
+       if (powersave)
+               fc |= cpu_to_le16(IEEE80211_FCTL_PM);
+       nullfunc->frame_control = fc;
+       memcpy(nullfunc->addr1, sdata->u.sta.bssid, ETH_ALEN);
+       memcpy(nullfunc->addr2, sdata->dev->dev_addr, ETH_ALEN);
+       memcpy(nullfunc->addr3, sdata->u.sta.bssid, ETH_ALEN);
+
+       ieee80211_sta_tx(sdata, skb, 0);
+}
+
+static void ieee80211_restart_sta_timer(struct ieee80211_sub_if_data *sdata)
+{
+       if (sdata->vif.type == IEEE80211_IF_TYPE_STA ||
+           ieee80211_vif_is_mesh(&sdata->vif))
+               ieee80211_sta_timer((unsigned long)sdata);
+}
+
+void ieee80211_scan_completed(struct ieee80211_hw *hw)
+{
+       struct ieee80211_local *local = hw_to_local(hw);
+       struct ieee80211_sub_if_data *sdata;
+       union iwreq_data wrqu;
+
+       local->last_scan_completed = jiffies;
+       memset(&wrqu, 0, sizeof(wrqu));
+       wireless_send_event(local->scan_sdata->dev, SIOCGIWSCAN, &wrqu, NULL);
+
+       if (local->sta_hw_scanning) {
+               local->sta_hw_scanning = 0;
+               if (ieee80211_hw_config(local))
+                       printk(KERN_DEBUG "%s: failed to restore operational "
+                              "channel after scan\n", wiphy_name(local->hw.wiphy));
+               /* Restart STA timer for HW scan case */
+               rcu_read_lock();
+               list_for_each_entry_rcu(sdata, &local->interfaces, list)
+                       ieee80211_restart_sta_timer(sdata);
+               rcu_read_unlock();
+
+               goto done;
+       }
+
+       local->sta_sw_scanning = 0;
+       if (ieee80211_hw_config(local))
+               printk(KERN_DEBUG "%s: failed to restore operational "
+                      "channel after scan\n", wiphy_name(local->hw.wiphy));
+
+
+       netif_tx_lock_bh(local->mdev);
+       netif_addr_lock(local->mdev);
+       local->filter_flags &= ~FIF_BCN_PRBRESP_PROMISC;
+       local->ops->configure_filter(local_to_hw(local),
+                                    FIF_BCN_PRBRESP_PROMISC,
+                                    &local->filter_flags,
+                                    local->mdev->mc_count,
+                                    local->mdev->mc_list);
+
+       netif_addr_unlock(local->mdev);
+       netif_tx_unlock_bh(local->mdev);
+
+       rcu_read_lock();
+       list_for_each_entry_rcu(sdata, &local->interfaces, list) {
+               /* Tell AP we're back */
+               if (sdata->vif.type == IEEE80211_IF_TYPE_STA) {
+                       if (sdata->u.sta.flags & IEEE80211_STA_ASSOCIATED) {
+                               ieee80211_send_nullfunc(local, sdata, 0);
+                               netif_tx_wake_all_queues(sdata->dev);
+                       }
+               } else
+                       netif_tx_wake_all_queues(sdata->dev);
+
+               ieee80211_restart_sta_timer(sdata);
+       }
+       rcu_read_unlock();
+
+ done:
+       ieee80211_mlme_notify_scan_completed(local);
+}
+EXPORT_SYMBOL(ieee80211_scan_completed);
+
+
+void ieee80211_sta_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 = local->scan_sdata;
+       struct ieee80211_supported_band *sband;
+       struct ieee80211_channel *chan;
+       int skip;
+       unsigned long next_delay = 0;
+
+       if (!local->sta_sw_scanning)
+               return;
+
+       switch (local->scan_state) {
+       case SCAN_SET_CHANNEL:
+               /*
+                * Get current scan band. scan_band may be IEEE80211_NUM_BANDS
+                * after we successfully scanned the last channel of the last
+                * band (and the last band is supported by the hw)
+                */
+               if (local->scan_band < IEEE80211_NUM_BANDS)
+                       sband = local->hw.wiphy->bands[local->scan_band];
+               else
+                       sband = NULL;
+
+               /*
+                * If we are at an unsupported band and have more bands
+                * left to scan, advance to the next supported one.
+                */
+               while (!sband && local->scan_band < IEEE80211_NUM_BANDS - 1) {
+                       local->scan_band++;
+                       sband = local->hw.wiphy->bands[local->scan_band];
+                       local->scan_channel_idx = 0;
+               }
+
+               /* if no more bands/channels left, complete scan */
+               if (!sband || local->scan_channel_idx >= sband->n_channels) {
+                       ieee80211_scan_completed(local_to_hw(local));
+                       return;
+               }
+               skip = 0;
+               chan = &sband->channels[local->scan_channel_idx];
+
+               if (chan->flags & IEEE80211_CHAN_DISABLED ||
+                   (sdata->vif.type == IEEE80211_IF_TYPE_IBSS &&
+                    chan->flags & IEEE80211_CHAN_NO_IBSS))
+                       skip = 1;
+
+               if (!skip) {
+                       local->scan_channel = chan;
+                       if (ieee80211_hw_config(local)) {
+                               printk(KERN_DEBUG "%s: failed to set freq to "
+                                      "%d MHz for scan\n", wiphy_name(local->hw.wiphy),
+                                      chan->center_freq);
+                               skip = 1;
+                       }
+               }
+
+               /* advance state machine to next channel/band */
+               local->scan_channel_idx++;
+               if (local->scan_channel_idx >= sband->n_channels) {
+                       /*
+                        * scan_band may end up == IEEE80211_NUM_BANDS, but
+                        * we'll catch that case above and complete the scan
+                        * if that is the case.
+                        */
+                       local->scan_band++;
+                       local->scan_channel_idx = 0;
+               }
+
+               if (skip)
+                       break;
+
+               next_delay = IEEE80211_PROBE_DELAY +
+                            usecs_to_jiffies(local->hw.channel_change_time);
+               local->scan_state = SCAN_SEND_PROBE;
+               break;
+       case SCAN_SEND_PROBE:
+               next_delay = IEEE80211_PASSIVE_CHANNEL_TIME;
+               local->scan_state = SCAN_SET_CHANNEL;
+
+               if (local->scan_channel->flags & IEEE80211_CHAN_PASSIVE_SCAN)
+                       break;
+               ieee80211_send_probe_req(sdata, NULL, local->scan_ssid,
+                                        local->scan_ssid_len);
+               next_delay = IEEE80211_CHANNEL_TIME;
+               break;
+       }
+
+       if (local->sta_sw_scanning)
+               queue_delayed_work(local->hw.workqueue, &local->scan_work,
+                                  next_delay);
+}
+
+
+int ieee80211_sta_start_scan(struct ieee80211_sub_if_data *scan_sdata,
+                            u8 *ssid, size_t ssid_len)
+{
+       struct ieee80211_local *local = scan_sdata->local;
+       struct ieee80211_sub_if_data *sdata;
+
+       if (ssid_len > IEEE80211_MAX_SSID_LEN)
+               return -EINVAL;
+
+       /* MLME-SCAN.request (page 118)  page 144 (11.1.3.1)
+        * BSSType: INFRASTRUCTURE, INDEPENDENT, ANY_BSS
+        * BSSID: MACAddress
+        * SSID
+        * ScanType: ACTIVE, PASSIVE
+        * ProbeDelay: delay (in microseconds) to be used prior to transmitting
+        *    a Probe frame during active scanning
+        * ChannelList
+        * MinChannelTime (>= ProbeDelay), in TU
+        * MaxChannelTime: (>= MinChannelTime), in TU
+        */
+
+        /* MLME-SCAN.confirm
+         * BSSDescriptionSet
+         * ResultCode: SUCCESS, INVALID_PARAMETERS
+        */
+
+       if (local->sta_sw_scanning || local->sta_hw_scanning) {
+               if (local->scan_sdata == scan_sdata)
+                       return 0;
+               return -EBUSY;
+       }
+
+       if (local->ops->hw_scan) {
+               int rc = local->ops->hw_scan(local_to_hw(local),
+                                            ssid, ssid_len);
+               if (!rc) {
+                       local->sta_hw_scanning = 1;
+                       local->scan_sdata = scan_sdata;
+               }
+               return rc;
+       }
+
+       local->sta_sw_scanning = 1;
+
+       rcu_read_lock();
+       list_for_each_entry_rcu(sdata, &local->interfaces, list) {
+               if (sdata->vif.type == IEEE80211_IF_TYPE_STA) {
+                       if (sdata->u.sta.flags & IEEE80211_STA_ASSOCIATED) {
+                               netif_tx_stop_all_queues(sdata->dev);
+                               ieee80211_send_nullfunc(local, sdata, 1);
+                       }
+               } else
+                       netif_tx_stop_all_queues(sdata->dev);
+       }
+       rcu_read_unlock();
+
+       if (ssid) {
+               local->scan_ssid_len = ssid_len;
+               memcpy(local->scan_ssid, ssid, ssid_len);
+       } else
+               local->scan_ssid_len = 0;
+       local->scan_state = SCAN_SET_CHANNEL;
+       local->scan_channel_idx = 0;
+       local->scan_band = IEEE80211_BAND_2GHZ;
+       local->scan_sdata = scan_sdata;
+
+       netif_addr_lock_bh(local->mdev);
+       local->filter_flags |= FIF_BCN_PRBRESP_PROMISC;
+       local->ops->configure_filter(local_to_hw(local),
+                                    FIF_BCN_PRBRESP_PROMISC,
+                                    &local->filter_flags,
+                                    local->mdev->mc_count,
+                                    local->mdev->mc_list);
+       netif_addr_unlock_bh(local->mdev);
+
+       /* TODO: start scan as soon as all nullfunc frames are ACKed */
+       queue_delayed_work(local->hw.workqueue, &local->scan_work,
+                          IEEE80211_CHANNEL_TIME);
+
+       return 0;
+}
+
+
+int ieee80211_sta_req_scan(struct ieee80211_sub_if_data *sdata, u8 *ssid, size_t ssid_len)
+{
+       struct ieee80211_if_sta *ifsta = &sdata->u.sta;
+       struct ieee80211_local *local = sdata->local;
+
+       if (sdata->vif.type != IEEE80211_IF_TYPE_STA)
+               return ieee80211_sta_start_scan(sdata, ssid, ssid_len);
+
+       if (local->sta_sw_scanning || local->sta_hw_scanning) {
+               if (local->scan_sdata == sdata)
+                       return 0;
+               return -EBUSY;
+       }
+
+       ifsta->scan_ssid_len = ssid_len;
+       if (ssid_len)
+               memcpy(ifsta->scan_ssid, ssid, ssid_len);
+       set_bit(IEEE80211_STA_REQ_SCAN, &ifsta->request);
+       queue_work(local->hw.workqueue, &ifsta->work);
+       return 0;
+}
+
+
+static void ieee80211_sta_add_scan_ies(struct iw_request_info *info,
+                                      struct ieee80211_sta_bss *bss,
+                                      char **current_ev, char *end_buf)
+{
+       u8 *pos, *end, *next;
+       struct iw_event iwe;
+
+       if (bss == NULL || bss->ies == NULL)
+               return;
+
+       /*
+        * If needed, fragment the IEs buffer (at IE boundaries) into short
+        * enough fragments to fit into IW_GENERIC_IE_MAX octet messages.
+        */
+       pos = bss->ies;
+       end = pos + bss->ies_len;
+
+       while (end - pos > IW_GENERIC_IE_MAX) {
+               next = pos + 2 + pos[1];
+               while (next + 2 + next[1] - pos < IW_GENERIC_IE_MAX)
+                       next = next + 2 + next[1];
+
+               memset(&iwe, 0, sizeof(iwe));
+               iwe.cmd = IWEVGENIE;
+               iwe.u.data.length = next - pos;
+               *current_ev = iwe_stream_add_point(info, *current_ev,
+                                                  end_buf, &iwe, pos);
+
+               pos = next;
+       }
+
+       if (end > pos) {
+               memset(&iwe, 0, sizeof(iwe));
+               iwe.cmd = IWEVGENIE;
+               iwe.u.data.length = end - pos;
+               *current_ev = iwe_stream_add_point(info, *current_ev,
+                                                  end_buf, &iwe, pos);
+       }
+}
+
+
+static char *
+ieee80211_sta_scan_result(struct ieee80211_local *local,
+                         struct iw_request_info *info,
+                         struct ieee80211_sta_bss *bss,
+                         char *current_ev, char *end_buf)
+{
+       struct iw_event iwe;
+       char *buf;
+
+       if (time_after(jiffies,
+                      bss->last_update + IEEE80211_SCAN_RESULT_EXPIRE))
+               return current_ev;
+
+       memset(&iwe, 0, sizeof(iwe));
+       iwe.cmd = SIOCGIWAP;
+       iwe.u.ap_addr.sa_family = ARPHRD_ETHER;
+       memcpy(iwe.u.ap_addr.sa_data, bss->bssid, ETH_ALEN);
+       current_ev = iwe_stream_add_event(info, current_ev, end_buf, &iwe,
+                                         IW_EV_ADDR_LEN);
+
+       memset(&iwe, 0, sizeof(iwe));
+       iwe.cmd = SIOCGIWESSID;
+       if (bss_mesh_cfg(bss)) {
+               iwe.u.data.length = bss_mesh_id_len(bss);
+               iwe.u.data.flags = 1;
+               current_ev = iwe_stream_add_point(info, current_ev, end_buf,
+                                                 &iwe, bss_mesh_id(bss));
+       } else {
+               iwe.u.data.length = bss->ssid_len;
+               iwe.u.data.flags = 1;
+               current_ev = iwe_stream_add_point(info, current_ev, end_buf,
+                                                 &iwe, bss->ssid);
+       }
+
+       if (bss->capability & (WLAN_CAPABILITY_ESS | WLAN_CAPABILITY_IBSS)
+           || bss_mesh_cfg(bss)) {
+               memset(&iwe, 0, sizeof(iwe));
+               iwe.cmd = SIOCGIWMODE;
+               if (bss_mesh_cfg(bss))
+                       iwe.u.mode = IW_MODE_MESH;
+               else if (bss->capability & WLAN_CAPABILITY_ESS)
+                       iwe.u.mode = IW_MODE_MASTER;
+               else
+                       iwe.u.mode = IW_MODE_ADHOC;
+               current_ev = iwe_stream_add_event(info, current_ev, end_buf,
+                                                 &iwe, IW_EV_UINT_LEN);
+       }
+
+       memset(&iwe, 0, sizeof(iwe));
+       iwe.cmd = SIOCGIWFREQ;
+       iwe.u.freq.m = ieee80211_frequency_to_channel(bss->freq);
+       iwe.u.freq.e = 0;
+       current_ev = iwe_stream_add_event(info, current_ev, end_buf, &iwe,
+                                         IW_EV_FREQ_LEN);
+
+       memset(&iwe, 0, sizeof(iwe));
+       iwe.cmd = SIOCGIWFREQ;
+       iwe.u.freq.m = bss->freq;
+       iwe.u.freq.e = 6;
+       current_ev = iwe_stream_add_event(info, current_ev, end_buf, &iwe,
+                                         IW_EV_FREQ_LEN);
+       memset(&iwe, 0, sizeof(iwe));
+       iwe.cmd = IWEVQUAL;
+       iwe.u.qual.qual = bss->qual;
+       iwe.u.qual.level = bss->signal;
+       iwe.u.qual.noise = bss->noise;
+       iwe.u.qual.updated = local->wstats_flags;
+       current_ev = iwe_stream_add_event(info, current_ev, end_buf, &iwe,
+                                         IW_EV_QUAL_LEN);
+
+       memset(&iwe, 0, sizeof(iwe));
+       iwe.cmd = SIOCGIWENCODE;
+       if (bss->capability & WLAN_CAPABILITY_PRIVACY)
+               iwe.u.data.flags = IW_ENCODE_ENABLED | IW_ENCODE_NOKEY;
+       else
+               iwe.u.data.flags = IW_ENCODE_DISABLED;
+       iwe.u.data.length = 0;
+       current_ev = iwe_stream_add_point(info, current_ev, end_buf,
+                                         &iwe, "");
+
+       ieee80211_sta_add_scan_ies(info, bss, &current_ev, end_buf);
+
+       if (bss->supp_rates_len > 0) {
+               /* display all supported rates in readable format */
+               char *p = current_ev + iwe_stream_lcp_len(info);
+               int i;
+
+               memset(&iwe, 0, sizeof(iwe));
+               iwe.cmd = SIOCGIWRATE;
+               /* Those two flags are ignored... */
+               iwe.u.bitrate.fixed = iwe.u.bitrate.disabled = 0;
+
+               for (i = 0; i < bss->supp_rates_len; i++) {
+                       iwe.u.bitrate.value = ((bss->supp_rates[i] &
+                                                       0x7f) * 500000);
+                       p = iwe_stream_add_value(info, current_ev, p,
+                                       end_buf, &iwe, IW_EV_PARAM_LEN);
+               }
+               current_ev = p;
+       }
+
+       buf = kmalloc(30, GFP_ATOMIC);
+       if (buf) {
+               memset(&iwe, 0, sizeof(iwe));
+               iwe.cmd = IWEVCUSTOM;
+               sprintf(buf, "tsf=%016llx", (unsigned long long)(bss->timestamp));
+               iwe.u.data.length = strlen(buf);
+               current_ev = iwe_stream_add_point(info, current_ev, end_buf,
+                                                 &iwe, buf);
+               memset(&iwe, 0, sizeof(iwe));
+               iwe.cmd = IWEVCUSTOM;
+               sprintf(buf, " Last beacon: %dms ago",
+                       jiffies_to_msecs(jiffies - bss->last_update));
+               iwe.u.data.length = strlen(buf);
+               current_ev = iwe_stream_add_point(info, current_ev,
+                                                 end_buf, &iwe, buf);
+               kfree(buf);
+       }
+
+       if (bss_mesh_cfg(bss)) {
+               u8 *cfg = bss_mesh_cfg(bss);
+               buf = kmalloc(50, GFP_ATOMIC);
+               if (buf) {
+                       memset(&iwe, 0, sizeof(iwe));
+                       iwe.cmd = IWEVCUSTOM;
+                       sprintf(buf, "Mesh network (version %d)", cfg[0]);
+                       iwe.u.data.length = strlen(buf);
+                       current_ev = iwe_stream_add_point(info, current_ev,
+                                                         end_buf,
+                                                         &iwe, buf);
+                       sprintf(buf, "Path Selection Protocol ID: "
+                               "0x%02X%02X%02X%02X", cfg[1], cfg[2], cfg[3],
+                                                       cfg[4]);
+                       iwe.u.data.length = strlen(buf);
+                       current_ev = iwe_stream_add_point(info, current_ev,
+                                                         end_buf,
+                                                         &iwe, buf);
+                       sprintf(buf, "Path Selection Metric ID: "
+                               "0x%02X%02X%02X%02X", cfg[5], cfg[6], cfg[7],
+                                                       cfg[8]);
+                       iwe.u.data.length = strlen(buf);
+                       current_ev = iwe_stream_add_point(info, current_ev,
+                                                         end_buf,
+                                                         &iwe, buf);
+                       sprintf(buf, "Congestion Control Mode ID: "
+                               "0x%02X%02X%02X%02X", cfg[9], cfg[10],
+                                                       cfg[11], cfg[12]);
+                       iwe.u.data.length = strlen(buf);
+                       current_ev = iwe_stream_add_point(info, current_ev,
+                                                         end_buf,
+                                                         &iwe, buf);
+                       sprintf(buf, "Channel Precedence: "
+                               "0x%02X%02X%02X%02X", cfg[13], cfg[14],
+                                                       cfg[15], cfg[16]);
+                       iwe.u.data.length = strlen(buf);
+                       current_ev = iwe_stream_add_point(info, current_ev,
+                                                         end_buf,
+                                                         &iwe, buf);
+                       kfree(buf);
+               }
+       }
+
+       return current_ev;
+}
+
+
+int ieee80211_sta_scan_results(struct ieee80211_local *local,
+                              struct iw_request_info *info,
+                              char *buf, size_t len)
+{
+       char *current_ev = buf;
+       char *end_buf = buf + len;
+       struct ieee80211_sta_bss *bss;
+
+       spin_lock_bh(&local->sta_bss_lock);
+       list_for_each_entry(bss, &local->sta_bss_list, list) {
+               if (buf + len - current_ev <= IW_EV_ADDR_LEN) {
+                       spin_unlock_bh(&local->sta_bss_lock);
+                       return -E2BIG;
+               }
+               current_ev = ieee80211_sta_scan_result(local, info, bss,
+                                                      current_ev, end_buf);
+       }
+       spin_unlock_bh(&local->sta_bss_lock);
+       return current_ev - buf;
+}