[RFCv2 1/3] mac80211: move mesh sync beacon handler into neighbour_update

[Marco Porsch <marco@cozybit.com>]

Move the beacon handler into mesh_neighbour_update where the STA
pointer is already available. This avoids additional overhead
and simplifies the handler.
The repositioning will also benefit mesh PS which uses the
T_offset value right after it has been updated.

Rename the handler to better reflect its purpose.

Signed-off-by: Marco Porsch <marco@cozybit.com>
---
 net/mac80211/ieee80211_i.h |   10 +++++-----
 net/mac80211/mesh.c        |    8 ++------
 net/mac80211/mesh.h        |    5 +++--
 net/mac80211/mesh_plink.c  |   16 ++++++++++++---
 net/mac80211/mesh_sync.c   |   47 +++++++++++++++-----------------------------
 5 files changed, 39 insertions(+), 47 deletions(-)

diff --git a/net/mac80211/ieee80211_i.h b/net/mac80211/ieee80211_i.h
index 650f758..bba2b10 100644
--- a/net/mac80211/ieee80211_i.h
+++ b/net/mac80211/ieee80211_i.h
@@ -560,11 +560,11 @@ struct ieee80211_if_ibss {
  */
 struct ieee802_11_elems;
 struct ieee80211_mesh_sync_ops {
-	void (*rx_bcn_presp)(struct ieee80211_sub_if_data *sdata,
-			     u16 stype,
-			     struct ieee80211_mgmt *mgmt,
-			     struct ieee802_11_elems *elems,
-			     struct ieee80211_rx_status *rx_status);
+	void (*rx_bcn)(struct sta_info *sta,
+		       struct ieee80211_mgmt *mgmt,
+		       struct ieee802_11_elems *elems,
+		       struct ieee80211_rx_status *rx_status,
+		       u64 tsf);
 	void (*adjust_tbtt)(struct ieee80211_sub_if_data *sdata);
 	/* add other framework functions here */
 };
diff --git a/net/mac80211/mesh.c b/net/mac80211/mesh.c
index e39a3f8..643262b 100644
--- a/net/mac80211/mesh.c
+++ b/net/mac80211/mesh.c
@@ -714,7 +714,6 @@ static void ieee80211_mesh_rx_bcn_presp(struct ieee80211_sub_if_data *sdata,
 					struct ieee80211_rx_status *rx_status)
 {
 	struct ieee80211_local *local = sdata->local;
-	struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
 	struct ieee802_11_elems elems;
 	struct ieee80211_channel *channel;
 	size_t baselen;
@@ -750,13 +749,10 @@ static void ieee80211_mesh_rx_bcn_presp(struct ieee80211_sub_if_data *sdata,
 		return;
 
 	if (mesh_matches_local(sdata, &elems))
-		mesh_neighbour_update(sdata, mgmt->sa, &elems);
-
-	if (ifmsh->sync_ops)
-		ifmsh->sync_ops->rx_bcn_presp(sdata,
-			stype, mgmt, &elems, rx_status);
+		mesh_neighbour_update(sdata, mgmt, &elems, rx_status);
 }
 
+
 static void ieee80211_mesh_rx_mgmt_action(struct ieee80211_sub_if_data *sdata,
 					  struct ieee80211_mgmt *mgmt,
 					  size_t len,
diff --git a/net/mac80211/mesh.h b/net/mac80211/mesh.h
index eb33625..d6d9933 100644
--- a/net/mac80211/mesh.h
+++ b/net/mac80211/mesh.h
@@ -283,8 +283,9 @@ int mesh_path_send_to_gates(struct mesh_path *mpath);
 int mesh_gate_num(struct ieee80211_sub_if_data *sdata);
 /* Mesh plinks */
 void mesh_neighbour_update(struct ieee80211_sub_if_data *sdata,
-			   u8 *hw_addr,
-			   struct ieee802_11_elems *ie);
+			   struct ieee80211_mgmt *mgmt,
+			   struct ieee802_11_elems *ie,
+			   struct ieee80211_rx_status *rx_status);
 bool mesh_peer_accepts_plinks(struct ieee802_11_elems *ie);
 u32 mesh_accept_plinks_update(struct ieee80211_sub_if_data *sdata);
 void mesh_plink_broken(struct sta_info *sta);
diff --git a/net/mac80211/mesh_plink.c b/net/mac80211/mesh_plink.c
index 57e7267..af6fbfd 100644
--- a/net/mac80211/mesh_plink.c
+++ b/net/mac80211/mesh_plink.c
@@ -12,6 +12,7 @@
 #include "ieee80211_i.h"
 #include "rate.h"
 #include "mesh.h"
+#include "driver-ops.h"
 
 #define PLINK_GET_LLID(p) (p + 2)
 #define PLINK_GET_PLID(p) (p + 4)
@@ -391,13 +392,19 @@ static struct sta_info *mesh_peer_init(struct ieee80211_sub_if_data *sdata,
 }
 
 void mesh_neighbour_update(struct ieee80211_sub_if_data *sdata,
-			   u8 *hw_addr,
-			   struct ieee802_11_elems *elems)
+			   struct ieee80211_mgmt *mgmt,
+			   struct ieee802_11_elems *elems,
+			   struct ieee80211_rx_status *rx_status)
 {
+	struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
 	struct sta_info *sta;
+	u64 tsf;
+
+	/* get tsf before entering rcu-read section */
+	tsf = drv_get_tsf(sdata->local, sdata);
 
 	rcu_read_lock();
-	sta = mesh_peer_init(sdata, hw_addr, elems);
+	sta = mesh_peer_init(sdata, mgmt->sa, elems);
 	if (!sta)
 		goto out;
 
@@ -408,6 +415,9 @@ void mesh_neighbour_update(struct ieee80211_sub_if_data *sdata,
 	    rssi_threshold_check(sta, sdata))
 		mesh_plink_open(sta);
 
+	if (ifmsh->sync_ops)
+		ifmsh->sync_ops->rx_bcn(sta, mgmt, elems, rx_status, tsf);
+
 	ieee80211_mps_frame_release(sta, elems);
 out:
 	rcu_read_unlock();
diff --git a/net/mac80211/mesh_sync.c b/net/mac80211/mesh_sync.c
index aa8d1e4..2275de4 100644
--- a/net/mac80211/mesh_sync.c
+++ b/net/mac80211/mesh_sync.c
@@ -75,35 +75,23 @@ void mesh_sync_adjust_tbtt(struct ieee80211_sub_if_data *sdata)
 		drv_set_tsf(local, sdata, tsf + tsfdelta);
 }
 
-static void mesh_sync_offset_rx_bcn_presp(struct ieee80211_sub_if_data *sdata,
-				   u16 stype,
-				   struct ieee80211_mgmt *mgmt,
-				   struct ieee802_11_elems *elems,
-				   struct ieee80211_rx_status *rx_status)
+static void mesh_sync_offset_rx_bcn(struct sta_info *sta,
+				    struct ieee80211_mgmt *mgmt,
+				    struct ieee802_11_elems *elems,
+				    struct ieee80211_rx_status *rx_status,
+				    u64 t_r)
 {
+	struct ieee80211_sub_if_data *sdata = sta->sdata;
 	struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
 	struct ieee80211_local *local = sdata->local;
-	struct sta_info *sta;
-	u64 t_t, t_r;
+	u64 t_t;
 
 	WARN_ON(ifmsh->mesh_sp_id != IEEE80211_SYNC_METHOD_NEIGHBOR_OFFSET);
 
 	/* standard mentions only beacons */
-	if (stype != IEEE80211_STYPE_BEACON)
+	if (!ieee80211_is_beacon(mgmt->frame_control))
 		return;
 
-	/* The current tsf is a first approximation for the timestamp
-	 * for the received beacon.  Further down we try to get a
-	 * better value from the rx_status->mactime field if
-	 * available. Also we have to call drv_get_tsf() before
-	 * entering the rcu-read section.*/
-	t_r = drv_get_tsf(local, sdata);
-
-	rcu_read_lock();
-	sta = sta_info_get(sdata, mgmt->sa);
-	if (!sta)
-		goto no_sync;
-
 	/* check offset sync conditions (13.13.2.2.1)
 	 *
 	 * TODO also sync to
@@ -113,11 +101,15 @@ static void mesh_sync_offset_rx_bcn_presp(struct ieee80211_sub_if_data *sdata,
 	if (elems->mesh_config && mesh_peer_tbtt_adjusting(elems)) {
 		clear_sta_flag(sta, WLAN_STA_TOFFSET_KNOWN);
 		msync_dbg(sdata, "STA %pM : is adjusting TBTT\n", sta->sta.addr);
-		goto no_sync;
+		return;
 	}
 
+	/*
+	 * The current tsf is a first approximation of the beacon RX time.
+	 * If available, get a better value from the rx_status->mactime field
+	 * (time when timestamp field was received).
+	 */
 	if (ieee80211_have_rx_timestamp(rx_status))
-		/* time when timestamp field was received */
 		t_r = ieee80211_calculate_rx_timestamp(local, rx_status,
 						       24 + 12 +
 						       elems->total_len +
@@ -146,11 +138,9 @@ static void mesh_sync_offset_rx_bcn_presp(struct ieee80211_sub_if_data *sdata,
 				  sta->sta.addr,
 				  (long long) t_clockdrift);
 			clear_sta_flag(sta, WLAN_STA_TOFFSET_KNOWN);
-			goto no_sync;
+			return;
 		}
 
-		rcu_read_unlock();
-
 		spin_lock_bh(&ifmsh->sync_offset_lock);
 		if (t_clockdrift >
 		    ifmsh->sync_offset_clockdrift_max)
@@ -165,12 +155,7 @@ static void mesh_sync_offset_rx_bcn_presp(struct ieee80211_sub_if_data *sdata,
 			  "STA %pM : offset was invalid, sta->t_offset=%lld\n",
 			  sta->sta.addr,
 			  (long long) sta->t_offset);
-		rcu_read_unlock();
 	}
-	return;
-
-no_sync:
-	rcu_read_unlock();
 }
 
 static void mesh_sync_offset_adjust_tbtt(struct ieee80211_sub_if_data *sdata)
@@ -212,7 +197,7 @@ static const struct sync_method sync_methods[] = {
 	{
 		.method = IEEE80211_SYNC_METHOD_NEIGHBOR_OFFSET,
 		.ops = {
-			.rx_bcn_presp = &mesh_sync_offset_rx_bcn_presp,
+			.rx_bcn = &mesh_sync_offset_rx_bcn,
 			.adjust_tbtt = &mesh_sync_offset_adjust_tbtt,
 		}
 	},
-- 
1.7.9.5