nl80211: support beacon report scanning

Beacon report radio measurement requires reporting observed BSSs
on the channels specified in the beacon request. If the measurement
mode is set to passive or active, it requires actually performing a
scan (passive or active, accordingly), and reporting the time that
the scan was started and the time each beacon/probe was received
(both in terms of TSF of the BSS of the requesting AP). If the
request mode is table, this information is optional.
In addition, the radio measurement request specifies the channel
dwell time for the measurement.

In order to use scan for beacon report when the mode is active or
passive, add a parameter to scan request that specifies the
channel dwell time, and add scan start time and beacon received time
to scan results information.

Supporting beacon report is required for Multi Band Operation (MBO).

Signed-off-by: Assaf Krauss <assaf.krauss@intel.com>
Signed-off-by: David Spinadel <david.spinadel@intel.com>
Signed-off-by: Avraham Stern <avraham.stern@intel.com>
Signed-off-by: Luca Coelho <luciano.coelho@intel.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

5 files changed, 78 insertions, 16 deletions

diff --git a/net/wireless/core.c b/net/wireless/core.c
index 39d9abd309ea..7645e97362c0 100644
--- a/net/wireless/core.c
+++ b/net/wireless/core.c
@@ -220,7 +220,7 @@ void cfg80211_stop_p2p_device(struct cfg80211_registered_device *rdev,
 
         if (rdev->scan_req && rdev->scan_req->wdev == wdev) {
                 if (WARN_ON(!rdev->scan_req->notified))
-                        rdev->scan_req->aborted = true;
+                        rdev->scan_req->info.aborted = true;
                 ___cfg80211_scan_done(rdev, false);
         }
 }
@@ -1087,7 +1087,7 @@ static int cfg80211_netdev_notifier_call(struct notifier_block *nb,
                 cfg80211_update_iface_num(rdev, wdev->iftype, -1);
                 if (rdev->scan_req && rdev->scan_req->wdev == wdev) {
                         if (WARN_ON(!rdev->scan_req->notified))
-                                rdev->scan_req->aborted = true;
+                                rdev->scan_req->info.aborted = true;
                         ___cfg80211_scan_done(rdev, false);
                 }
 
diff --git a/net/wireless/core.h b/net/wireless/core.h
index a4d547f99f8d..eee91443924d 100644
--- a/net/wireless/core.h
+++ b/net/wireless/core.h
@@ -141,6 +141,18 @@ struct cfg80211_internal_bss {
         unsigned long refcount;
         atomic_t hold;
 
+        /* time at the start of the reception of the first octet of the
+         * timestamp field of the last beacon/probe received for this BSS.
+         * The time is the TSF of the BSS specified by %parent_bssid.
+         */
+        u64 parent_tsf;
+
+        /* the BSS according to which %parent_tsf is set. This is set to
+         * the BSS that the interface that requested the scan was connected to
+         * when the beacon/probe was received.
+         */
+        u8 parent_bssid[ETH_ALEN] __aligned(2);
+
         /* must be last because of priv member */
         struct cfg80211_bss pub;
 };
diff --git a/net/wireless/nl80211.c b/net/wireless/nl80211.c
index 447026f8cc76..c53b5462ed00 100644
--- a/net/wireless/nl80211.c
+++ b/net/wireless/nl80211.c
@@ -6223,6 +6223,19 @@ static int nl80211_trigger_scan(struct sk_buff *skb, struct genl_info *info)
                 }
         }
 
+        if (info->attrs[NL80211_ATTR_MEASUREMENT_DURATION]) {
+                if (!wiphy_ext_feature_isset(wiphy,
+                                        NL80211_EXT_FEATURE_SET_SCAN_DWELL)) {
+                        err = -EOPNOTSUPP;
+                        goto out_free;
+                }
+
+                request->duration =
+                        nla_get_u16(info->attrs[NL80211_ATTR_MEASUREMENT_DURATION]);
+                request->duration_mandatory =
+                        nla_get_flag(info->attrs[NL80211_ATTR_MEASUREMENT_DURATION_MANDATORY]);
+        }
+
         if (info->attrs[NL80211_ATTR_SCAN_FLAGS]) {
                 request->flags = nla_get_u32(
                         info->attrs[NL80211_ATTR_SCAN_FLAGS]);
@@ -7056,6 +7069,13 @@ static int nl80211_send_bss(struct sk_buff *msg, struct netlink_callback *cb,
                         jiffies_to_msecs(jiffies - intbss->ts)))
                 goto nla_put_failure;
 
+        if (intbss->parent_tsf &&
+            (nla_put_u64_64bit(msg, NL80211_BSS_PARENT_TSF,
+                               intbss->parent_tsf, NL80211_BSS_PAD) ||
+             nla_put(msg, NL80211_BSS_PARENT_BSSID, ETH_ALEN,
+                     intbss->parent_bssid)))
+                goto nla_put_failure;
+
         if (intbss->ts_boottime &&
             nla_put_u64_64bit(msg, NL80211_BSS_LAST_SEEN_BOOTTIME,
                               intbss->ts_boottime, NL80211_BSS_PAD))
@@ -11829,6 +11849,13 @@ static int nl80211_add_scan_req(struct sk_buff *msg,
             nla_put_u32(msg, NL80211_ATTR_SCAN_FLAGS, req->flags))
                 goto nla_put_failure;
 
+        if (req->info.scan_start_tsf &&
+            (nla_put_u64_64bit(msg, NL80211_ATTR_SCAN_START_TIME_TSF,
+                               req->info.scan_start_tsf, NL80211_BSS_PAD) ||
+             nla_put(msg, NL80211_ATTR_SCAN_START_TIME_TSF_BSSID, ETH_ALEN,
+                     req->info.tsf_bssid)))
+                goto nla_put_failure;
+
         return 0;
  nla_put_failure:
         return -ENOBUFS;
diff --git a/net/wireless/scan.c b/net/wireless/scan.c
index ef2955c89a00..0358e12be54b 100644
--- a/net/wireless/scan.c
+++ b/net/wireless/scan.c
@@ -3,6 +3,7 @@
  *
  * Copyright 2008 Johannes Berg <johannes@sipsolutions.net>
  * Copyright 2013-2014  Intel Mobile Communications GmbH
+ * Copyright 2016       Intel Deutschland GmbH
  */
 #include <linux/kernel.h>
 #include <linux/slab.h>
@@ -194,7 +195,7 @@ void ___cfg80211_scan_done(struct cfg80211_registered_device *rdev,
         if (wdev->netdev)
                 cfg80211_sme_scan_done(wdev->netdev);
 
-        if (!request->aborted &&
+        if (!request->info.aborted &&
             request->flags & NL80211_SCAN_FLAG_FLUSH) {
                 /* flush entries from previous scans */
                 spin_lock_bh(&rdev->bss_lock);
@@ -202,10 +203,10 @@ void ___cfg80211_scan_done(struct cfg80211_registered_device *rdev,
                 spin_unlock_bh(&rdev->bss_lock);
         }
 
-        msg = nl80211_build_scan_msg(rdev, wdev, request->aborted);
+        msg = nl80211_build_scan_msg(rdev, wdev, request->info.aborted);
 
 #ifdef CONFIG_CFG80211_WEXT
-        if (wdev->netdev && !request->aborted) {
+        if (wdev->netdev && !request->info.aborted) {
                 memset(&wrqu, 0, sizeof(wrqu));
 
                 wireless_send_event(wdev->netdev, SIOCGIWSCAN, &wrqu, NULL);
@@ -236,12 +237,13 @@ void __cfg80211_scan_done(struct work_struct *wk)
         rtnl_unlock();
 }
 
-void cfg80211_scan_done(struct cfg80211_scan_request *request, bool aborted)
+void cfg80211_scan_done(struct cfg80211_scan_request *request,
+                        struct cfg80211_scan_info *info)
 {
-        trace_cfg80211_scan_done(request, aborted);
+        trace_cfg80211_scan_done(request, info);
         WARN_ON(request != wiphy_to_rdev(request->wiphy)->scan_req);
 
-        request->aborted = aborted;
+        request->info = *info;
         request->notified = true;
         queue_work(cfg80211_wq, &wiphy_to_rdev(request->wiphy)->scan_done_wk);
 }
@@ -843,6 +845,8 @@ cfg80211_bss_update(struct cfg80211_registered_device *rdev,
                 found->pub.capability = tmp->pub.capability;
                 found->ts = tmp->ts;
                 found->ts_boottime = tmp->ts_boottime;
+                found->parent_tsf = tmp->parent_tsf;
+                ether_addr_copy(found->parent_bssid, tmp->parent_bssid);
         } else {
                 struct cfg80211_internal_bss *new;
                 struct cfg80211_internal_bss *hidden;
@@ -1086,6 +1090,8 @@ cfg80211_inform_bss_frame_data(struct wiphy *wiphy,
         tmp.pub.beacon_interval = le16_to_cpu(mgmt->u.probe_resp.beacon_int);
         tmp.pub.capability = le16_to_cpu(mgmt->u.probe_resp.capab_info);
         tmp.ts_boottime = data->boottime_ns;
+        tmp.parent_tsf = data->parent_tsf;
+        ether_addr_copy(tmp.parent_bssid, data->parent_bssid);
 
         signal_valid = abs(data->chan->center_freq - channel->center_freq) <=
                 wiphy->max_adj_channel_rssi_comp;
diff --git a/net/wireless/trace.h b/net/wireless/trace.h
index 3c1091ae6c36..72b5255cefe2 100644
--- a/net/wireless/trace.h
+++ b/net/wireless/trace.h
@@ -2642,8 +2642,9 @@ TRACE_EVENT(cfg80211_tdls_oper_request,
         );
 
 TRACE_EVENT(cfg80211_scan_done,
-        TP_PROTO(struct cfg80211_scan_request *request, bool aborted),
-        TP_ARGS(request, aborted),
+        TP_PROTO(struct cfg80211_scan_request *request,
+                 struct cfg80211_scan_info *info),
+        TP_ARGS(request, info),
         TP_STRUCT__entry(
                 __field(u32, n_channels)
                 __dynamic_array(u8, ie, request ? request->ie_len : 0)
@@ -2652,6 +2653,8 @@ TRACE_EVENT(cfg80211_scan_done,
                 MAC_ENTRY(wiphy_mac)
                 __field(bool, no_cck)
                 __field(bool, aborted)
+                __field(u64, scan_start_tsf)
+                MAC_ENTRY(tsf_bssid)
         ),
         TP_fast_assign(
                 if (request) {
@@ -2666,9 +2669,16 @@ TRACE_EVENT(cfg80211_scan_done,
                                            request->wiphy->perm_addr);
                         __entry->no_cck = request->no_cck;
                 }
-                __entry->aborted = aborted;
+                if (info) {
+                        __entry->aborted = info->aborted;
+                        __entry->scan_start_tsf = info->scan_start_tsf;
+                        MAC_ASSIGN(tsf_bssid, info->tsf_bssid);
+                }
         ),
-        TP_printk("aborted: %s", BOOL_TO_STR(__entry->aborted))
+        TP_printk("aborted: %s, scan start (TSF): %llu, tsf_bssid: " MAC_PR_FMT,
+                  BOOL_TO_STR(__entry->aborted),
+                  (unsigned long long)__entry->scan_start_tsf,
+                  MAC_PR_ARG(tsf_bssid))
 );
 
 DEFINE_EVENT(wiphy_only_evt, cfg80211_sched_scan_results,
@@ -2721,6 +2731,8 @@ TRACE_EVENT(cfg80211_inform_bss_frame,
                 __dynamic_array(u8, mgmt, len)
                 __field(s32, signal)
                 __field(u64, ts_boottime)
+                __field(u64, parent_tsf)
+                MAC_ENTRY(parent_bssid)
         ),
         TP_fast_assign(
                 WIPHY_ASSIGN;
@@ -2730,10 +2742,15 @@ TRACE_EVENT(cfg80211_inform_bss_frame,
                         memcpy(__get_dynamic_array(mgmt), mgmt, len);
                 __entry->signal = data->signal;
                 __entry->ts_boottime = data->boottime_ns;
-        ),
-        TP_printk(WIPHY_PR_FMT ", " CHAN_PR_FMT "(scan_width: %d) signal: %d, tsb:%llu",
-                  WIPHY_PR_ARG, CHAN_PR_ARG, __entry->scan_width,
-                  __entry->signal, (unsigned long long)__entry->ts_boottime)
+                __entry->parent_tsf = data->parent_tsf;
+                MAC_ASSIGN(parent_bssid, data->parent_bssid);
+        ),
+        TP_printk(WIPHY_PR_FMT ", " CHAN_PR_FMT
+                  "(scan_width: %d) signal: %d, tsb:%llu, detect_tsf:%llu, tsf_bssid: "
+                  MAC_PR_FMT, WIPHY_PR_ARG, CHAN_PR_ARG, __entry->scan_width,
+                  __entry->signal, (unsigned long long)__entry->ts_boottime,
+                  (unsigned long long)__entry->parent_tsf,
+                  MAC_PR_ARG(parent_bssid))
 );
 
 DECLARE_EVENT_CLASS(cfg80211_bss_evt,