[PATCHv3 0/6] Export the expected throughput towards a peer

[PATCHv3 0/6] Export the expected throughput towards a peer

[Antonio Quartulli]

Changes since v2:
- fix throughput computation in minstrel
- squash minstrel patches

Changes since v1:
- add expected throughput nl80211 attribute to the GET_STATION reply
  message
- the unit of the exported value has been changed to kbps
- the way the exported value was computed in minstrel and minstrel_ht has been
  changed after having really understood what minstrel is doing (thanks
  Johannes!)
- the number of arguments of the RC api have been reduced
- allow the API result to be 0 if the underlying layer does not know what to
  report
- squash ex patch 2/3/4
- use wiphy_to_rdev() where needed


Antonio Quartulli (4):
  cfg80211: export expected throughput through get_station()
  cfg80211: export expected throughput via nl80211 (GET_STATION)
  mac80211: export the expected throughput
  cfg80211: implement cfg80211_get_station cfg80211 API

 include/net/cfg80211.h             | 75 ++++++++++++++++++++++++--------------
 include/net/mac80211.h             |  7 ++++
 include/uapi/linux/nl80211.h       |  3 ++
 net/mac80211/cfg.c                 | 19 ++++++++++
 net/mac80211/driver-ops.h          | 13 +++++++
 net/mac80211/rc80211_minstrel.c    | 12 ++++++
 net/mac80211/rc80211_minstrel_ht.c | 17 +++++++++
 net/mac80211/trace.h               | 32 ++++++++++++++++
 net/wireless/nl80211.c             |  4 ++
 net/wireless/util.c                | 18 +++++++++
 10 files changed, 172 insertions(+), 28 deletions(-)

-- 
1.8.5.5

[PATCHv3 1/4] cfg80211: export expected throughput through get_station()

[Antonio Quartulli]

From: Antonio Quartulli <antonio@open-mesh.com>

Users may need information about the expected throughput
towards a given peer.
This value is supposed to consider the size overhead
generated by the 802.11 header.

Export such value in kbps through the get_station() API
(by including it into the station_info object).

This information will be useful to the batman-adv module
which will use it for its new metric computation.

Signed-off-by: Antonio Quartulli <antonio@open-mesh.com>
---
 include/net/cfg80211.h | 62 +++++++++++++++++++++++++++-----------------------
 1 file changed, 34 insertions(+), 28 deletions(-)

diff --git a/include/net/cfg80211.h b/include/net/cfg80211.h
index 447cb58..394189e 100644
--- a/include/net/cfg80211.h
+++ b/include/net/cfg80211.h
@@ -873,36 +873,38 @@ int cfg80211_check_station_change(struct wiphy *wiphy,
  * @STATION_INFO_NONPEER_PM: @nonpeer_pm filled
  * @STATION_INFO_CHAIN_SIGNAL: @chain_signal filled
  * @STATION_INFO_CHAIN_SIGNAL_AVG: @chain_signal_avg filled
+ * @STATION_INFO_EXPECTED_THROUGHPUT: @expected_throughput filled
  */
 enum station_info_flags {
-	STATION_INFO_INACTIVE_TIME	= 1<<0,
-	STATION_INFO_RX_BYTES		= 1<<1,
-	STATION_INFO_TX_BYTES		= 1<<2,
-	STATION_INFO_LLID		= 1<<3,
-	STATION_INFO_PLID		= 1<<4,
-	STATION_INFO_PLINK_STATE	= 1<<5,
-	STATION_INFO_SIGNAL		= 1<<6,
-	STATION_INFO_TX_BITRATE		= 1<<7,
-	STATION_INFO_RX_PACKETS		= 1<<8,
-	STATION_INFO_TX_PACKETS		= 1<<9,
-	STATION_INFO_TX_RETRIES		= 1<<10,
-	STATION_INFO_TX_FAILED		= 1<<11,
-	STATION_INFO_RX_DROP_MISC	= 1<<12,
-	STATION_INFO_SIGNAL_AVG		= 1<<13,
-	STATION_INFO_RX_BITRATE		= 1<<14,
-	STATION_INFO_BSS_PARAM          = 1<<15,
-	STATION_INFO_CONNECTED_TIME	= 1<<16,
-	STATION_INFO_ASSOC_REQ_IES	= 1<<17,
-	STATION_INFO_STA_FLAGS		= 1<<18,
-	STATION_INFO_BEACON_LOSS_COUNT	= 1<<19,
-	STATION_INFO_T_OFFSET		= 1<<20,
-	STATION_INFO_LOCAL_PM		= 1<<21,
-	STATION_INFO_PEER_PM		= 1<<22,
-	STATION_INFO_NONPEER_PM		= 1<<23,
-	STATION_INFO_RX_BYTES64		= 1<<24,
-	STATION_INFO_TX_BYTES64		= 1<<25,
-	STATION_INFO_CHAIN_SIGNAL	= 1<<26,
-	STATION_INFO_CHAIN_SIGNAL_AVG	= 1<<27,
+	STATION_INFO_INACTIVE_TIME		= BIT(0),
+	STATION_INFO_RX_BYTES			= BIT(1),
+	STATION_INFO_TX_BYTES			= BIT(2),
+	STATION_INFO_LLID			= BIT(3),
+	STATION_INFO_PLID			= BIT(4),
+	STATION_INFO_PLINK_STATE		= BIT(5),
+	STATION_INFO_SIGNAL			= BIT(6),
+	STATION_INFO_TX_BITRATE			= BIT(7),
+	STATION_INFO_RX_PACKETS			= BIT(8),
+	STATION_INFO_TX_PACKETS			= BIT(9),
+	STATION_INFO_TX_RETRIES			= BIT(10),
+	STATION_INFO_TX_FAILED			= BIT(11),
+	STATION_INFO_RX_DROP_MISC		= BIT(12),
+	STATION_INFO_SIGNAL_AVG			= BIT(13),
+	STATION_INFO_RX_BITRATE			= BIT(14),
+	STATION_INFO_BSS_PARAM			= BIT(15),
+	STATION_INFO_CONNECTED_TIME		= BIT(16),
+	STATION_INFO_ASSOC_REQ_IES		= BIT(17),
+	STATION_INFO_STA_FLAGS			= BIT(18),
+	STATION_INFO_BEACON_LOSS_COUNT		= BIT(19),
+	STATION_INFO_T_OFFSET			= BIT(20),
+	STATION_INFO_LOCAL_PM			= BIT(21),
+	STATION_INFO_PEER_PM			= BIT(22),
+	STATION_INFO_NONPEER_PM			= BIT(23),
+	STATION_INFO_RX_BYTES64			= BIT(24),
+	STATION_INFO_TX_BYTES64			= BIT(25),
+	STATION_INFO_CHAIN_SIGNAL		= BIT(26),
+	STATION_INFO_CHAIN_SIGNAL_AVG		= BIT(27),
+	STATION_INFO_EXPECTED_THROUGHPUT	= BIT(28),
 };
 
 /**
@@ -1024,6 +1026,8 @@ struct sta_bss_parameters {
  * @local_pm: local mesh STA power save mode
  * @peer_pm: peer mesh STA power save mode
  * @nonpeer_pm: non-peer mesh STA power save mode
+ * @expected_throughput: expected throughput in kbps (including 802.11 headers)
+ *	towards this station.
  */
 struct station_info {
 	u32 filled;
@@ -1062,6 +1066,8 @@ struct station_info {
 	enum nl80211_mesh_power_mode peer_pm;
 	enum nl80211_mesh_power_mode nonpeer_pm;
 
+	u32 expected_throughput;
+
 	/*
 	 * Note: Add a new enum station_info_flags value for each new field and
 	 * use it to check which fields are initialized.
-- 
1.8.5.5

[PATCHv3 2/4] cfg80211: export expected throughput via nl80211 (GET_STATION)

[Antonio Quartulli]

From: Antonio Quartulli <antonio@open-mesh.com>

Send the expected throughput when replying to a GET_STATION
command via nl80211.

Signed-off-by: Antonio Quartulli <antonio@open-mesh.com>
---
 include/uapi/linux/nl80211.h | 3 +++
 net/wireless/nl80211.c       | 4 ++++
 2 files changed, 7 insertions(+)

diff --git a/include/uapi/linux/nl80211.h b/include/uapi/linux/nl80211.h
index 0cfa827..2964948 100644
--- a/include/uapi/linux/nl80211.h
+++ b/include/uapi/linux/nl80211.h
@@ -2199,6 +2199,8 @@ enum nl80211_sta_bss_param {
  *	Contains a nested array of signal strength attributes (u8, dBm)
  * @NL80211_STA_INFO_CHAIN_SIGNAL_AVG: per-chain signal strength average
  *	Same format as NL80211_STA_INFO_CHAIN_SIGNAL.
+ * @NL80211_STA_EXPECTED_THROUGHPUT: expected throughput (considering also the
+ *	802.11 header) expressed in kbps
  * @__NL80211_STA_INFO_AFTER_LAST: internal
  * @NL80211_STA_INFO_MAX: highest possible station info attribute
  */
@@ -2230,6 +2232,7 @@ enum nl80211_sta_info {
 	NL80211_STA_INFO_TX_BYTES64,
 	NL80211_STA_INFO_CHAIN_SIGNAL,
 	NL80211_STA_INFO_CHAIN_SIGNAL_AVG,
+	NL80211_STA_INFO_EXPECTED_THROUGHPUT,
 
 	/* keep last */
 	__NL80211_STA_INFO_AFTER_LAST,
diff --git a/net/wireless/nl80211.c b/net/wireless/nl80211.c
index ca19b15..9631648 100644
--- a/net/wireless/nl80211.c
+++ b/net/wireless/nl80211.c
@@ -3650,6 +3650,10 @@ static int nl80211_send_station(struct sk_buff *msg, u32 portid, u32 seq,
 	    nla_put_u32(msg, NL80211_STA_INFO_TX_FAILED,
 			sinfo->tx_failed))
 		goto nla_put_failure;
+	if ((sinfo->filled & STATION_INFO_EXPECTED_THROUGHPUT) &&
+	    nla_put_u32(msg, NL80211_STA_INFO_EXPECTED_THROUGHPUT,
+			sinfo->expected_throughput))
+		goto nla_put_failure;
 	if ((sinfo->filled & STATION_INFO_BEACON_LOSS_COUNT) &&
 	    nla_put_u32(msg, NL80211_STA_INFO_BEACON_LOSS,
 			sinfo->beacon_loss_count))
-- 
1.8.5.5

Re: [PATCHv3 2/4] cfg80211: export expected throughput via nl80211 (GET_STATION)

[Johannes Berg]

On Sat, 2014-05-17 at 18:41 +0200, Antonio Quartulli wrote:
> From: Antonio Quartulli <antonio@open-mesh.com>
> 
> Send the expected throughput when replying to a GET_STATION
> command via nl80211.
> 
> Signed-off-by: Antonio Quartulli <antonio@open-mesh.com>
> ---
>  include/uapi/linux/nl80211.h | 3 +++
>  net/wireless/nl80211.c       | 4 ++++
>  2 files changed, 7 insertions(+)
> 
> diff --git a/include/uapi/linux/nl80211.h b/include/uapi/linux/nl80211.h
> index 0cfa827..2964948 100644
> --- a/include/uapi/linux/nl80211.h
> +++ b/include/uapi/linux/nl80211.h
> @@ -2199,6 +2199,8 @@ enum nl80211_sta_bss_param {
>   *	Contains a nested array of signal strength attributes (u8, dBm)
>   * @NL80211_STA_INFO_CHAIN_SIGNAL_AVG: per-chain signal strength average
>   *	Same format as NL80211_STA_INFO_CHAIN_SIGNAL.
> + * @NL80211_STA_EXPECTED_THROUGHPUT: expected throughput (considering also the
> + *	802.11 header) expressed in kbps

This should say it's a u32.

johannes

Re: [PATCHv3 2/4] cfg80211: export expected throughput via nl80211 (GET_STATION)

[Johannes Berg]

On Sat, 2014-05-17 at 18:41 +0200, Antonio Quartulli wrote:
> From: Antonio Quartulli <antonio@open-mesh.com>
> 
> Send the expected throughput when replying to a GET_STATION
> command via nl80211.

Since both are pretty short I think you might also just squash patches 1
and 2.

johannes

Re: [PATCHv3 2/4] cfg80211: export expected throughput via nl80211 (GET_STATION)

[Antonio Quartulli]

[-- Attachment #1: Type: text/plain, Size: 450 bytes --]

On 19/05/14 17:00, Johannes Berg wrote:
> On Sat, 2014-05-17 at 18:41 +0200, Antonio Quartulli wrote:
>> From: Antonio Quartulli <antonio@open-mesh.com>
>>
>> Send the expected throughput when replying to a GET_STATION
>> command via nl80211.
> 
> Since both are pretty short I think you might also just squash patches 1
> and 2.

Ok, will resend with 1/4 and 2/4 squashed and I'll add the u32 spec.

Thanks!

-- 
Antonio Quartulli


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[PATCHv3 3/4] mac80211: export the expected throughput

[Antonio Quartulli]

From: Antonio Quartulli <antonio@open-mesh.com>

Add get_expected_throughput() API to mac80211 so that each
driver can implement its own version based on the RC
algorithm they are using (might be using an HW RC algo).
The API returns a value expressed in Kbps.

Also, add the new get_expected_throughput() member
to the rate_control_ops structure in order to be
able to query the RC algorithm (this patch provides an
implementation of this API for both minstrel and
minstrel_ht).

The related member in the station_info object is now
filled accordingly when dumping a station.

Cc: Felix Fietkau <nbd@openwrt.org>
Signed-off-by: Antonio Quartulli <antonio@open-mesh.com>
---
 include/net/mac80211.h             |  7 +++++++
 net/mac80211/cfg.c                 | 19 +++++++++++++++++++
 net/mac80211/driver-ops.h          | 13 +++++++++++++
 net/mac80211/rc80211_minstrel.c    | 12 ++++++++++++
 net/mac80211/rc80211_minstrel_ht.c | 17 +++++++++++++++++
 net/mac80211/trace.h               | 32 ++++++++++++++++++++++++++++++++
 6 files changed, 100 insertions(+)

diff --git a/include/net/mac80211.h b/include/net/mac80211.h
index 982d2cd..81efbc7 100644
--- a/include/net/mac80211.h
+++ b/include/net/mac80211.h
@@ -2769,6 +2769,10 @@ enum ieee80211_roc_type {
  *	information in bss_conf is set up and the beacon can be retrieved. A
  *	channel context is bound before this is called.
  * @leave_ibss: Leave the IBSS again.
+ *
+ * @get_expected_throughput: extract the expected throughput towards the
+ *	specified station. The returned value is expressed in Kbps. It returns 0
+ *	if the RC algorithm does not have proper data to provide.
  */
 struct ieee80211_ops {
 	void (*tx)(struct ieee80211_hw *hw,
@@ -2962,6 +2966,7 @@ struct ieee80211_ops {
 
 	int (*join_ibss)(struct ieee80211_hw *hw, struct ieee80211_vif *vif);
 	void (*leave_ibss)(struct ieee80211_hw *hw, struct ieee80211_vif *vif);
+	u32 (*get_expected_throughput)(struct ieee80211_sta *sta);
 };
 
 /**
@@ -4534,6 +4539,8 @@ struct rate_control_ops {
 	void (*add_sta_debugfs)(void *priv, void *priv_sta,
 				struct dentry *dir);
 	void (*remove_sta_debugfs)(void *priv, void *priv_sta);
+
+	u32 (*get_expected_throughput)(void *priv_sta);
 };
 
 static inline int rate_supported(struct ieee80211_sta *sta,
diff --git a/net/mac80211/cfg.c b/net/mac80211/cfg.c
index bfd2534..d739409 100644
--- a/net/mac80211/cfg.c
+++ b/net/mac80211/cfg.c
@@ -472,8 +472,12 @@ static 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 = local->rate_ctrl;
+	struct ieee80211_supported_band *sband;
+	enum ieee80211_band band;
 	struct timespec uptime;
 	u64 packets = 0;
+	u32 thr = 0;
 	int i, ac;
 
 	sinfo->generation = sdata->local->sta_generation;
@@ -587,6 +591,21 @@ static void sta_set_sinfo(struct sta_info *sta, struct station_info *sinfo)
 		sinfo->sta_flags.set |= BIT(NL80211_STA_FLAG_ASSOCIATED);
 	if (test_sta_flag(sta, WLAN_STA_TDLS_PEER))
 		sinfo->sta_flags.set |= BIT(NL80211_STA_FLAG_TDLS_PEER);
+
+	/* check if the driver has a SW RC implementation */
+	if (ref && ref->ops->get_expected_throughput) {
+		band = ieee80211_get_sdata_band(sta->sdata);
+		sband = sta->local->hw.wiphy->bands[band];
+
+		thr = ref->ops->get_expected_throughput(sta->rate_ctrl_priv);
+	} else {
+		thr = drv_get_expected_throughput(local, &sta->sta);
+	}
+
+	if (thr != 0) {
+		sinfo->filled |= STATION_INFO_EXPECTED_THROUGHPUT;
+		sinfo->expected_throughput = thr;
+	}
 }
 
 static const char ieee80211_gstrings_sta_stats[][ETH_GSTRING_LEN] = {
diff --git a/net/mac80211/driver-ops.h b/net/mac80211/driver-ops.h
index df1d502..696ef78 100644
--- a/net/mac80211/driver-ops.h
+++ b/net/mac80211/driver-ops.h
@@ -1156,4 +1156,17 @@ static inline void drv_leave_ibss(struct ieee80211_local *local,
 	trace_drv_return_void(local);
 }
 
+static inline u32 drv_get_expected_throughput(struct ieee80211_local *local,
+					      struct ieee80211_sta *sta)
+{
+	u32 ret = 0;
+
+	trace_drv_get_expected_throughput(sta);
+	if (local->ops->get_expected_throughput)
+		ret = local->ops->get_expected_throughput(sta);
+	trace_drv_return_u32(local, ret);
+
+	return ret;
+}
+
 #endif /* __MAC80211_DRIVER_OPS */
diff --git a/net/mac80211/rc80211_minstrel.c b/net/mac80211/rc80211_minstrel.c
index 26fd94f..1c1469c 100644
--- a/net/mac80211/rc80211_minstrel.c
+++ b/net/mac80211/rc80211_minstrel.c
@@ -657,6 +657,17 @@ minstrel_free(void *priv)
 	kfree(priv);
 }
 
+static u32 minstrel_get_expected_throughput(void *priv_sta)
+{
+	struct minstrel_sta_info *mi = priv_sta;
+	int idx = mi->max_tp_rate[0];
+
+	/* convert pkt per sec in kbps (1200 is the average pkt size used for
+	 * computing cur_tp
+	 */
+	return MINSTREL_TRUNC(mi->r[idx].cur_tp) * 1200 * 8 / 1024;
+}
+
 const struct rate_control_ops mac80211_minstrel = {
 	.name = "minstrel",
 	.tx_status = minstrel_tx_status,
@@ -670,6 +681,7 @@ const struct rate_control_ops mac80211_minstrel = {
 	.add_sta_debugfs = minstrel_add_sta_debugfs,
 	.remove_sta_debugfs = minstrel_remove_sta_debugfs,
 #endif
+	.get_expected_throughput = minstrel_get_expected_throughput,
 };
 
 int __init
diff --git a/net/mac80211/rc80211_minstrel_ht.c b/net/mac80211/rc80211_minstrel_ht.c
index bccaf85..949fb01 100644
--- a/net/mac80211/rc80211_minstrel_ht.c
+++ b/net/mac80211/rc80211_minstrel_ht.c
@@ -1031,6 +1031,22 @@ minstrel_ht_free(void *priv)
 	mac80211_minstrel.free(priv);
 }
 
+static u32 minstrel_ht_get_expected_throughput(void *priv_sta)
+{
+	struct minstrel_ht_sta_priv *msp = priv_sta;
+	struct minstrel_ht_sta *mi = &msp->ht;
+	int i, j;
+
+	if (!msp->is_ht)
+		return mac80211_minstrel.get_expected_throughput(priv_sta);
+
+	i = mi->max_tp_rate / MCS_GROUP_RATES;
+	j = mi->max_tp_rate % MCS_GROUP_RATES;
+
+	/* convert cur_tp from pkt per second in kbps */
+	return mi->groups[i].rates[j].cur_tp * AVG_PKT_SIZE * 8 / 1024;
+}
+
 static const struct rate_control_ops mac80211_minstrel_ht = {
 	.name = "minstrel_ht",
 	.tx_status = minstrel_ht_tx_status,
@@ -1045,6 +1061,7 @@ static const struct rate_control_ops mac80211_minstrel_ht = {
 	.add_sta_debugfs = minstrel_ht_add_sta_debugfs,
 	.remove_sta_debugfs = minstrel_ht_remove_sta_debugfs,
 #endif
+	.get_expected_throughput = minstrel_ht_get_expected_throughput,
 };
 
 
diff --git a/net/mac80211/trace.h b/net/mac80211/trace.h
index a0b0aea..942f64b 100644
--- a/net/mac80211/trace.h
+++ b/net/mac80211/trace.h
@@ -184,6 +184,20 @@ TRACE_EVENT(drv_return_bool,
 		  "true" : "false")
 );
 
+TRACE_EVENT(drv_return_u32,
+	TP_PROTO(struct ieee80211_local *local, u32 ret),
+	TP_ARGS(local, ret),
+	TP_STRUCT__entry(
+		LOCAL_ENTRY
+		__field(u32, ret)
+	),
+	TP_fast_assign(
+		LOCAL_ASSIGN;
+		__entry->ret = ret;
+	),
+	TP_printk(LOCAL_PR_FMT " - %u", LOCAL_PR_ARG, __entry->ret)
+);
+
 TRACE_EVENT(drv_return_u64,
 	TP_PROTO(struct ieee80211_local *local, u64 ret),
 	TP_ARGS(local, ret),
@@ -1499,6 +1513,24 @@ DEFINE_EVENT(local_sdata_evt, drv_leave_ibss,
 	TP_ARGS(local, sdata)
 );
 
+TRACE_EVENT(drv_get_expected_throughput,
+	TP_PROTO(struct ieee80211_sta *sta),
+
+	TP_ARGS(sta),
+
+	TP_STRUCT__entry(
+		STA_ENTRY
+	),
+
+	TP_fast_assign(
+		STA_ASSIGN;
+	),
+
+	TP_printk(
+		STA_PR_FMT, STA_PR_ARG
+	)
+);
+
 /*
  * Tracing for API calls that drivers call.
  */
-- 
1.8.5.5

[PATCHv3 4/4] cfg80211: implement cfg80211_get_station cfg80211 API

[Antonio Quartulli]

From: Antonio Quartulli <antonio@open-mesh.com>

Implement and export the new cfg80211_get_station() API.
This utility can be used by other kernel modules to obtain
detailed information about a given wireless station.

It will be in particular useful to batman-adv which will
implement a wireless rate based metric.

Signed-off-by: Antonio Quartulli <antonio@open-mesh.com>
---
 include/net/cfg80211.h | 13 +++++++++++++
 net/wireless/util.c    | 18 ++++++++++++++++++
 2 files changed, 31 insertions(+)

diff --git a/include/net/cfg80211.h b/include/net/cfg80211.h
index 394189e..5917919 100644
--- a/include/net/cfg80211.h
+++ b/include/net/cfg80211.h
@@ -1075,6 +1075,19 @@ struct station_info {
 };
 
 /**
+ * cfg80211_get_station - retrieve information about a given station
+ * @dev: the device where the station is supposed to be connected to
+ * @mac_addr: the mac address of the station of interest
+ * @sinfo: pointer to the structure to fill with the information
+ *
+ * Returns 0 on success and sinfo is filled with the available information
+ * otherwise returns a negative error code and the content of sinfo has to be
+ * considered undefined.
+ */
+int cfg80211_get_station(struct net_device *dev, u8 *mac_addr,
+			 struct station_info *sinfo);
+
+/**
  * enum monitor_flags - monitor flags
  *
  * Monitor interface configuration flags. Note that these must be the bits
diff --git a/net/wireless/util.c b/net/wireless/util.c
index 8c61d5c..6380e55 100644
--- a/net/wireless/util.c
+++ b/net/wireless/util.c
@@ -1545,6 +1545,24 @@ unsigned int ieee80211_get_num_supported_channels(struct wiphy *wiphy)
 }
 EXPORT_SYMBOL(ieee80211_get_num_supported_channels);
 
+int cfg80211_get_station(struct net_device *dev, u8 *mac_addr,
+			 struct station_info *sinfo)
+{
+	struct cfg80211_registered_device *rdev;
+	struct wireless_dev *wdev;
+
+	wdev = dev->ieee80211_ptr;
+	if (!wdev)
+		return -EOPNOTSUPP;
+
+	rdev = wiphy_to_rdev(wdev->wiphy);
+	if (!rdev->ops->get_station)
+		return -EOPNOTSUPP;
+
+	return rdev_get_station(rdev, dev, mac_addr, sinfo);
+}
+EXPORT_SYMBOL(cfg80211_get_station);
+
 /* See IEEE 802.1H for LLC/SNAP encapsulation/decapsulation */
 /* Ethernet-II snap header (RFC1042 for most EtherTypes) */
 const unsigned char rfc1042_header[] __aligned(2) =
-- 
1.8.5.5