3 files changed, 33 insertions, 17 deletions

diff --git a/include/net/cfg80211.h b/include/net/cfg80211.h
index 3b489f8fc4cd..5a861440c122 100644
--- a/include/net/cfg80211.h
+++ b/include/net/cfg80211.h
@@ -542,7 +542,8 @@ enum survey_info_flags {
 /**
  * struct survey_info - channel survey response
  *
- * @channel: the channel this survey record reports, mandatory
+ * @channel: the channel this survey record reports, may be %NULL for a single
+ *      record to report global statistics
  * @filled: bitflag of flags from &enum survey_info_flags
  * @noise: channel noise in dBm. This and all following fields are
  *      optional
diff --git a/include/uapi/linux/nl80211.h b/include/uapi/linux/nl80211.h
index 1a5acc80ab88..5e8b65f239a5 100644
--- a/include/uapi/linux/nl80211.h
+++ b/include/uapi/linux/nl80211.h
@@ -1727,6 +1727,14 @@ enum nl80211_commands {
  *      is located at bit 0 of byte 0. bit index 25 would be located at bit 1
  *      of byte 3 (u8 array).
  *
+ * @NL80211_ATTR_SURVEY_RADIO_STATS: Request overall radio statistics to be
+ *      returned along with other survey data. If set, @NL80211_CMD_GET_SURVEY
+ *      may return a survey entry without a channel indicating global radio
+ *      statistics (only some values are valid and make sense.)
+ *      For devices that don't return such an entry even then, the information
+ *      should be contained in the result as the sum of the respective counters
+ *      over all channels.
+ *
  * @NUM_NL80211_ATTR: total number of nl80211_attrs available
  * @NL80211_ATTR_MAX: highest attribute number currently defined
  * @__NL80211_ATTR_AFTER_LAST: internal use
@@ -2088,6 +2096,8 @@ enum nl80211_attrs {
 
         NL80211_ATTR_EXT_FEATURES,
 
+        NL80211_ATTR_SURVEY_RADIO_STATS,
+
         /* add attributes here, update the policy in nl80211.c */
 
         __NL80211_ATTR_AFTER_LAST,
@@ -2816,15 +2826,15 @@ enum nl80211_user_reg_hint_type {
  * @NL80211_SURVEY_INFO_NOISE: noise level of channel (u8, dBm)
  * @NL80211_SURVEY_INFO_IN_USE: channel is currently being used
  * @NL80211_SURVEY_INFO_TIME: amount of time (in ms) that the radio
- *      spent on this channel
+ *      was turned on (on channel or globally)
  * @NL80211_SURVEY_INFO_TIME_BUSY: amount of the time the primary
  *      channel was sensed busy (either due to activity or energy detect)
  * @NL80211_SURVEY_INFO_TIME_EXT_BUSY: amount of time the extension
  *      channel was sensed busy
  * @NL80211_SURVEY_INFO_TIME_RX: amount of time the radio spent
- *      receiving data
+ *      receiving data (on channel or globally)
  * @NL80211_SURVEY_INFO_TIME_TX: amount of time the radio spent
- *      transmitting data
+ *      transmitting data (on channel or globally)
  * @NL80211_SURVEY_INFO_MAX: highest survey info attribute number
  *      currently defined
  * @__NL80211_SURVEY_INFO_AFTER_LAST: internal use
diff --git a/net/wireless/nl80211.c b/net/wireless/nl80211.c
index 94ab2014fefe..9555ef9fd99e 100644
--- a/net/wireless/nl80211.c
+++ b/net/wireless/nl80211.c
@@ -6613,12 +6613,17 @@ static int nl80211_dump_scan(struct sk_buff *skb, struct netlink_callback *cb)
 }
 
 static int nl80211_send_survey(struct sk_buff *msg, u32 portid, u32 seq,
-                                int flags, struct net_device *dev,
-                                struct survey_info *survey)
+                               int flags, struct net_device *dev,
+                               bool allow_radio_stats,
+                               struct survey_info *survey)
 {
         void *hdr;
         struct nlattr *infoattr;
 
+        /* skip radio stats if userspace didn't request them */
+        if (!survey->channel && !allow_radio_stats)
+                return 0;
+
         hdr = nl80211hdr_put(msg, portid, seq, flags,
                              NL80211_CMD_NEW_SURVEY_RESULTS);
         if (!hdr)
@@ -6631,7 +6636,8 @@ static int nl80211_send_survey(struct sk_buff *msg, u32 portid, u32 seq,
         if (!infoattr)
                 goto nla_put_failure;
 
-        if (nla_put_u32(msg, NL80211_SURVEY_INFO_FREQUENCY,
+        if (survey->channel &&
+            nla_put_u32(msg, NL80211_SURVEY_INFO_FREQUENCY,
                         survey->channel->center_freq))
                 goto nla_put_failure;
 
@@ -6671,19 +6677,22 @@ static int nl80211_send_survey(struct sk_buff *msg, u32 portid, u32 seq,
         return -EMSGSIZE;
 }
 
-static int nl80211_dump_survey(struct sk_buff *skb,
-                        struct netlink_callback *cb)
+static int nl80211_dump_survey(struct sk_buff *skb, struct netlink_callback *cb)
 {
         struct survey_info survey;
         struct cfg80211_registered_device *rdev;
         struct wireless_dev *wdev;
         int survey_idx = cb->args[2];
         int res;
+        bool radio_stats;
 
         res = nl80211_prepare_wdev_dump(skb, cb, &rdev, &wdev);
         if (res)
                 return res;
 
+        /* prepare_wdev_dump parsed the attributes */
+        radio_stats = nl80211_fam.attrbuf[NL80211_ATTR_SURVEY_RADIO_STATS];
+
         if (!wdev->netdev) {
                 res = -EINVAL;
                 goto out_err;
@@ -6701,13 +6710,9 @@ static int nl80211_dump_survey(struct sk_buff *skb,
                 if (res)
                         goto out_err;
 
-                /* Survey without a channel doesn't make sense */
-                if (!survey.channel) {
-                        res = -EINVAL;
-                        goto out;
-                }
-
-                if (survey.channel->flags & IEEE80211_CHAN_DISABLED) {
+                /* don't send disabled channels, but do send non-channel data */
+                if (survey.channel &&
+                    survey.channel->flags & IEEE80211_CHAN_DISABLED) {
                         survey_idx++;
                         continue;
                 }
@@ -6715,7 +6720,7 @@ static int nl80211_dump_survey(struct sk_buff *skb,
                 if (nl80211_send_survey(skb,
                                 NETLINK_CB(cb->skb).portid,
                                 cb->nlh->nlmsg_seq, NLM_F_MULTI,
-                                wdev->netdev, &survey) < 0)
+                                wdev->netdev, radio_stats, &survey) < 0)
                         goto out;
                 survey_idx++;
         }