cfg80211: add KHz variants of frame RX API

Drivers may wish to report the RX frequency in units of
KHz. Provide cfg80211_rx_mgmt_khz() and wrap it with
cfg80211_rx_mgmt() so exisiting drivers which can't report
KHz anyway don't need to change. Add a similar wrapper for
cfg80211_report_obss_beacon() so the frequency units stay
somewhat consistent.

This doesn't actually change the nl80211 API yet.
Signed-off-by: Thomas Pedersen <thomas@adapt-ip.com>
Link: https://lore.kernel.org/r/20200430172554.18383-2-thomas@adapt-ip.com
[fix mac80211 calling the non-khz version of obss beacon report,
 drop trace point name changes]
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

include/linux/ieee80211.h

@@ -3333,6 +3333,8 @@ static inline int ieee80211_get_tdls_action(struct sk_buff *skb, u32 hdr_size)
 /* convert frequencies */
 #define MHZ_TO_KHZ(freq) ((freq) * 1000)
 #define KHZ_TO_MHZ(freq) ((freq) / 1000)
+#define PR_KHZ(f) KHZ_TO_MHZ(f), f % 1000
+#define KHZ_F "%d.%03d"
 
 /* convert powers */
 #define DBI_TO_MBI(gain) ((gain) * 100)

include/net/cfg80211.h

@@ -6988,6 +6988,26 @@ void cfg80211_conn_failed(struct net_device *dev, const u8 *mac_addr,
 			  enum nl80211_connect_failed_reason reason,
 			  gfp_t gfp);
 
+/**
+ * cfg80211_rx_mgmt_khz - notification of received, unprocessed management frame
+ * @wdev: wireless device receiving the frame
+ * @freq: Frequency on which the frame was received in KHz
+ * @sig_dbm: signal strength in dBm, or 0 if unknown
+ * @buf: Management frame (header + body)
+ * @len: length of the frame data
+ * @flags: flags, as defined in enum nl80211_rxmgmt_flags
+ *
+ * This function is called whenever an Action frame is received for a station
+ * mode interface, but is not processed in kernel.
+ *
+ * Return: %true if a user space application has registered for this frame.
+ * For action frames, that makes it responsible for rejecting unrecognized
+ * action frames; %false otherwise, in which case for action frames the
+ * driver is responsible for rejecting the frame.
+ */
+bool cfg80211_rx_mgmt_khz(struct wireless_dev *wdev, int freq, int sig_dbm,
+			  const u8 *buf, size_t len, u32 flags);
+
 /**
  * cfg80211_rx_mgmt - notification of received, unprocessed management frame
  * @wdev: wireless device receiving the frame
@@ -7005,8 +7025,13 @@ void cfg80211_conn_failed(struct net_device *dev, const u8 *mac_addr,
  * action frames; %false otherwise, in which case for action frames the
  * driver is responsible for rejecting the frame.
  */
-bool cfg80211_rx_mgmt(struct wireless_dev *wdev, int freq, int sig_dbm,
-		      const u8 *buf, size_t len, u32 flags);
+static inline bool cfg80211_rx_mgmt(struct wireless_dev *wdev, int freq,
+				    int sig_dbm, const u8 *buf, size_t len,
+				    u32 flags)
+{
+	return cfg80211_rx_mgmt_khz(wdev, MHZ_TO_KHZ(freq), sig_dbm, buf, len,
+				    flags);
+}
 
 /**
  * cfg80211_mgmt_tx_status - notification of TX status for management frame
@@ -7204,6 +7229,21 @@ void cfg80211_probe_status(struct net_device *dev, const u8 *addr,
 			   u64 cookie, bool acked, s32 ack_signal,
 			   bool is_valid_ack_signal, gfp_t gfp);
 
+/**
+ * cfg80211_report_obss_beacon_khz - report beacon from other APs
+ * @wiphy: The wiphy that received the beacon
+ * @frame: the frame
+ * @len: length of the frame
+ * @freq: frequency the frame was received on in KHz
+ * @sig_dbm: signal strength in dBm, or 0 if unknown
+ *
+ * Use this function to report to userspace when a beacon was
+ * received. It is not useful to call this when there is no
+ * netdev that is in AP/GO mode.
+ */
+void cfg80211_report_obss_beacon_khz(struct wiphy *wiphy, const u8 *frame,
+				     size_t len, int freq, int sig_dbm);
+
 /**
  * cfg80211_report_obss_beacon - report beacon from other APs
  * @wiphy: The wiphy that received the beacon
@@ -7216,9 +7256,13 @@ void cfg80211_probe_status(struct net_device *dev, const u8 *addr,
  * received. It is not useful to call this when there is no
  * netdev that is in AP/GO mode.
  */
-void cfg80211_report_obss_beacon(struct wiphy *wiphy,
-				 const u8 *frame, size_t len,
-				 int freq, int sig_dbm);
+static inline void cfg80211_report_obss_beacon(struct wiphy *wiphy,
+					       const u8 *frame, size_t len,
+					       int freq, int sig_dbm)
+{
+	cfg80211_report_obss_beacon_khz(wiphy, frame, len, MHZ_TO_KHZ(freq),
+					sig_dbm);
+}
 
 /**
  * cfg80211_reg_can_beacon - check if beaconing is allowed

net/mac80211/rx.c

@@ -3095,9 +3095,10 @@ ieee80211_rx_h_mgmt_check(struct ieee80211_rx_data *rx)
 		    !(status->flag & RX_FLAG_NO_SIGNAL_VAL))
 			sig = status->signal;
 
-		cfg80211_report_obss_beacon(rx->local->hw.wiphy,
-					    rx->skb->data, rx->skb->len,
-					    status->freq, sig);
+		cfg80211_report_obss_beacon_khz(rx->local->hw.wiphy,
+						rx->skb->data, rx->skb->len,
+						ieee80211_rx_status_to_khz(status),
+						sig);
 		rx->flags |= IEEE80211_RX_BEACON_REPORTED;
 	}
 
@@ -3443,8 +3444,9 @@ ieee80211_rx_h_userspace_mgmt(struct ieee80211_rx_data *rx)
 	    !(status->flag & RX_FLAG_NO_SIGNAL_VAL))
 		sig = status->signal;
 
-	if (cfg80211_rx_mgmt(&rx->sdata->wdev, status->freq, sig,
-			     rx->skb->data, rx->skb->len, 0)) {
+	if (cfg80211_rx_mgmt_khz(&rx->sdata->wdev,
+				 ieee80211_rx_status_to_khz(status), sig,
+				 rx->skb->data, rx->skb->len, 0)) {
 		if (rx->sta)
 			rx->sta->rx_stats.packets++;
 		dev_kfree_skb(rx->skb);

net/wireless/mlme.c

@@ -729,8 +729,8 @@ int cfg80211_mlme_mgmt_tx(struct cfg80211_registered_device *rdev,
 	return rdev_mgmt_tx(rdev, wdev, params, cookie);
 }
 
-bool cfg80211_rx_mgmt(struct wireless_dev *wdev, int freq, int sig_dbm,
-		      const u8 *buf, size_t len, u32 flags)
+bool cfg80211_rx_mgmt_khz(struct wireless_dev *wdev, int freq, int sig_dbm,
+			  const u8 *buf, size_t len, u32 flags)
 {
 	struct wiphy *wiphy = wdev->wiphy;
 	struct cfg80211_registered_device *rdev = wiphy_to_rdev(wiphy);
@@ -785,7 +785,7 @@ bool cfg80211_rx_mgmt(struct wireless_dev *wdev, int freq, int sig_dbm,
 	trace_cfg80211_return_bool(result);
 	return result;
 }
-EXPORT_SYMBOL(cfg80211_rx_mgmt);
+EXPORT_SYMBOL(cfg80211_rx_mgmt_khz);
 
 void cfg80211_sched_dfs_chan_update(struct cfg80211_registered_device *rdev)
 {

net/wireless/nl80211.c

@@ -16214,7 +16214,7 @@ int nl80211_send_mgmt(struct cfg80211_registered_device *rdev,
 					netdev->ifindex)) ||
 	    nla_put_u64_64bit(msg, NL80211_ATTR_WDEV, wdev_id(wdev),
 			      NL80211_ATTR_PAD) ||
-	    nla_put_u32(msg, NL80211_ATTR_WIPHY_FREQ, freq) ||
+	    nla_put_u32(msg, NL80211_ATTR_WIPHY_FREQ, KHZ_TO_MHZ(freq)) ||
 	    (sig_dbm &&
 	     nla_put_u32(msg, NL80211_ATTR_RX_SIGNAL_DBM, sig_dbm)) ||
 	    nla_put(msg, NL80211_ATTR_FRAME, len, buf) ||
@@ -16840,9 +16840,8 @@ void cfg80211_probe_status(struct net_device *dev, const u8 *addr,
 }
 EXPORT_SYMBOL(cfg80211_probe_status);
 
-void cfg80211_report_obss_beacon(struct wiphy *wiphy,
-				 const u8 *frame, size_t len,
-				 int freq, int sig_dbm)
+void cfg80211_report_obss_beacon_khz(struct wiphy *wiphy, const u8 *frame,
+				     size_t len, int freq, int sig_dbm)
 {
 	struct cfg80211_registered_device *rdev = wiphy_to_rdev(wiphy);
 	struct sk_buff *msg;
@@ -16865,7 +16864,8 @@ void cfg80211_report_obss_beacon(struct wiphy *wiphy,
 
 		if (nla_put_u32(msg, NL80211_ATTR_WIPHY, rdev->wiphy_idx) ||
 		    (freq &&
-		     nla_put_u32(msg, NL80211_ATTR_WIPHY_FREQ, freq)) ||
+		     nla_put_u32(msg, NL80211_ATTR_WIPHY_FREQ,
+				 KHZ_TO_MHZ(freq))) ||
 		    (sig_dbm &&
 		     nla_put_u32(msg, NL80211_ATTR_RX_SIGNAL_DBM, sig_dbm)) ||
 		    nla_put(msg, NL80211_ATTR_FRAME, len, frame))
@@ -16882,7 +16882,7 @@ void cfg80211_report_obss_beacon(struct wiphy *wiphy,
 	spin_unlock_bh(&rdev->beacon_registrations_lock);
 	nlmsg_free(msg);
 }
-EXPORT_SYMBOL(cfg80211_report_obss_beacon);
+EXPORT_SYMBOL(cfg80211_report_obss_beacon_khz);
 
 #ifdef CONFIG_PM
 static int cfg80211_net_detect_results(struct sk_buff *msg,

net/wireless/trace.h

@@ -2840,8 +2840,8 @@ TRACE_EVENT(cfg80211_rx_mgmt,
 		__entry->freq = freq;
 		__entry->sig_dbm = sig_dbm;
 	),
-	TP_printk(WDEV_PR_FMT ", freq: %d, sig dbm: %d",
-		  WDEV_PR_ARG, __entry->freq, __entry->sig_dbm)
+	TP_printk(WDEV_PR_FMT ", freq: "KHZ_F", sig dbm: %d",
+		  WDEV_PR_ARG, PR_KHZ(__entry->freq), __entry->sig_dbm)
 );
 
 TRACE_EVENT(cfg80211_mgmt_tx_status,
@@ -3121,8 +3121,8 @@ TRACE_EVENT(cfg80211_report_obss_beacon,
 		__entry->freq = freq;
 		__entry->sig_dbm = sig_dbm;
 	),
-	TP_printk(WIPHY_PR_FMT ", freq: %d, sig_dbm: %d",
-		  WIPHY_PR_ARG, __entry->freq, __entry->sig_dbm)
+	TP_printk(WIPHY_PR_FMT ", freq: "KHZ_F", sig_dbm: %d",
+		  WIPHY_PR_ARG, PR_KHZ(__entry->freq), __entry->sig_dbm)
 );
 
 TRACE_EVENT(cfg80211_tdls_oper_request,