mac80211: use ktime_get_seconds

The mac80211 code uses ktime_get_ts to measure the connected time.
As this uses monotonic time, it is y2038 safe on 32-bit systems,
but we still want to deprecate the use of 'timespec' because most
other users are broken.

This changes the code to use ktime_get_seconds() instead, which
avoids the timespec structure and is slightly more efficient.
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Cc: Johannes Berg <johannes@sipsolutions.net>
Cc: linux-wireless@vger.kernel.org
Signed-off-by: David S. Miller <davem@davemloft.net>

net/mac80211/sta_info.c

@@ -303,7 +303,6 @@ struct sta_info *sta_info_alloc(struct ieee80211_sub_if_data *sdata,
 	struct ieee80211_local *local = sdata->local;
 	struct ieee80211_hw *hw = &local->hw;
 	struct sta_info *sta;
-	struct timespec uptime;
 	int i;
 
 	sta = kzalloc(sizeof(*sta) + hw->sta_data_size, gfp);
@@ -339,8 +338,7 @@ struct sta_info *sta_info_alloc(struct ieee80211_sub_if_data *sdata,
 	/* Mark TID as unreserved */
 	sta->reserved_tid = IEEE80211_TID_UNRESERVED;
 
-	ktime_get_ts(&uptime);
-	sta->last_connected = uptime.tv_sec;
+	sta->last_connected = ktime_get_seconds();
 	ewma_signal_init(&sta->avg_signal);
 	for (i = 0; i < ARRAY_SIZE(sta->chain_signal_avg); i++)
 		ewma_signal_init(&sta->chain_signal_avg[i]);
@@ -1813,7 +1811,6 @@ void sta_set_sinfo(struct sta_info *sta, struct station_info *sinfo)
 	struct ieee80211_sub_if_data *sdata = sta->sdata;
 	struct ieee80211_local *local = sdata->local;
 	struct rate_control_ref *ref = NULL;
-	struct timespec uptime;
 	u32 thr = 0;
 	int i, ac;
 
@@ -1838,8 +1835,7 @@ void sta_set_sinfo(struct sta_info *sta, struct station_info *sinfo)
 			 BIT(NL80211_STA_INFO_RX_DROP_MISC) |
 			 BIT(NL80211_STA_INFO_BEACON_LOSS);
 
-	ktime_get_ts(&uptime);
-	sinfo->connected_time = uptime.tv_sec - sta->last_connected;
+	sinfo->connected_time = ktime_get_seconds() - sta->last_connected;
 	sinfo->inactive_time = jiffies_to_msecs(jiffies - sta->last_rx);
 
 	if (!(sinfo->filled & (BIT(NL80211_STA_INFO_TX_BYTES64) |