Search Linux Wireless

Re: [PATCH v2 2/3] mac80211: cache mesh beacon

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

 



When re-submitting, could you please check if you unintentionally removed the call to ieee80211_mps_set_frame_flags when building the beacon?

--Marco


On 02/13/2013 09:14 PM, Thomas Pedersen wrote:
Previously, the entire mesh beacon would be generated each
time the beacon timer fired. Instead generate a beacon
head and tail (so the TIM can easily be inserted when mesh
power save is on) when starting a mesh or the MBSS
parameters change.

Also add a mutex for protecting beacon updates and
preventing leaks.

Signed-off-by: Thomas Pedersen <thomas@xxxxxxxxxxx>
---

v2:
	less verbose, fix RCU usage (Johannes)
	protect beacon updates (Johannes)

  net/mac80211/cfg.c         |    5 +-
  net/mac80211/ieee80211_i.h |    3 +
  net/mac80211/mesh.c        |  146 +++++++++++++++++++++++++++++++++++++++++++-
  net/mac80211/mesh.h        |    3 +
  net/mac80211/mesh_plink.c  |    4 +-
  net/mac80211/tx.c          |   61 +++---------------
  6 files changed, 162 insertions(+), 60 deletions(-)

diff --git a/net/mac80211/cfg.c b/net/mac80211/cfg.c
index 6a39d38..5388054e 100644
--- a/net/mac80211/cfg.c
+++ b/net/mac80211/cfg.c
@@ -1803,11 +1803,10 @@ static int ieee80211_update_mesh_config(struct wiphy *wiphy,
  		conf->power_mode = nconf->power_mode;
  		ieee80211_mps_local_status_update(sdata);
  	}
-	if (_chg_mesh_attr(NL80211_MESHCONF_AWAKE_WINDOW, mask)) {
+	if (_chg_mesh_attr(NL80211_MESHCONF_AWAKE_WINDOW, mask))
  		conf->dot11MeshAwakeWindowDuration =
  			nconf->dot11MeshAwakeWindowDuration;
-		ieee80211_bss_info_change_notify(sdata, BSS_CHANGED_BEACON);
-	}
+	ieee80211_mbss_info_change_notify(sdata, BSS_CHANGED_BEACON);
  	return 0;
  }

diff --git a/net/mac80211/ieee80211_i.h b/net/mac80211/ieee80211_i.h
index 0e0a977..959888c 100644
--- a/net/mac80211/ieee80211_i.h
+++ b/net/mac80211/ieee80211_i.h
@@ -578,6 +578,9 @@ struct ieee80211_if_mesh {
  	u32 mesh_seqnum;
  	bool accepting_plinks;
  	int num_gates;
+	struct beacon_data __rcu *beacon;
+	/* just protects beacon updates for now */
+	struct mutex mtx;
  	const u8 *ie;
  	u8 ie_len;
  	enum {
diff --git a/net/mac80211/mesh.c b/net/mac80211/mesh.c
index 0adec3d..d9426e0 100644
--- a/net/mac80211/mesh.c
+++ b/net/mac80211/mesh.c
@@ -171,7 +171,7 @@ void mesh_sta_cleanup(struct sta_info *sta)
  	}

  	if (changed)
-		ieee80211_bss_info_change_notify(sdata, changed);
+		ieee80211_mbss_info_change_notify(sdata, changed);
  }

  int mesh_rmc_init(struct ieee80211_sub_if_data *sdata)
@@ -593,7 +593,7 @@ static void ieee80211_mesh_housekeeping(struct ieee80211_sub_if_data *sdata,
  	mesh_path_expire(sdata);

  	changed = mesh_accept_plinks_update(sdata);
-	ieee80211_bss_info_change_notify(sdata, changed);
+	ieee80211_mbss_info_change_notify(sdata, changed);

  	mod_timer(&ifmsh->housekeeping_timer,
  		  round_jiffies(jiffies + IEEE80211_MESH_HOUSEKEEPING_INTERVAL));
@@ -644,6 +644,139 @@ void ieee80211_mesh_restart(struct ieee80211_sub_if_data *sdata)
  }
  #endif

+static int
+ieee80211_mesh_build_beacon(struct ieee80211_if_mesh *ifmsh)
+{
+	struct beacon_data *bcn;
+	int head_len, tail_len;
+	struct sk_buff *skb;
+	struct ieee80211_mgmt *mgmt;
+	struct ieee80211_chanctx_conf *chanctx_conf;
+	enum ieee80211_band band;
+	u8 *pos;
+	struct ieee80211_sub_if_data *sdata;
+	int hdr_len = offsetof(struct ieee80211_mgmt, u.beacon) +
+		      sizeof(mgmt->u.beacon);
+
+	sdata = container_of(ifmsh, struct ieee80211_sub_if_data, u.mesh);
+	rcu_read_lock();
+	chanctx_conf = rcu_dereference(sdata->vif.chanctx_conf);
+	band = chanctx_conf->def.chan->band;
+	rcu_read_unlock();
+
+	head_len = hdr_len +
+		   2 + /* NULL SSID */
+		   2 + 8 + /* supported rates */
+		   2 + 3; /* DS params */
+	tail_len = 2 + (IEEE80211_MAX_SUPP_RATES - 8) +
+		   2 + sizeof(struct ieee80211_ht_cap) +
+		   2 + sizeof(struct ieee80211_ht_operation) +
+		   2 + ifmsh->mesh_id_len +
+		   2 + sizeof(struct ieee80211_meshconf_ie) +
+		   2 + sizeof(__le16) + /* awake window */
+		   ifmsh->ie_len;
+
+	bcn = kzalloc(sizeof(*bcn) + head_len + tail_len, GFP_KERNEL);
+	/* need an skb for IE builders to operate on */
+	skb = dev_alloc_skb(max(head_len, tail_len));
+
+	if (!bcn || !skb)
+		goto out_free;
+
+	/*
+	 * pointers go into the block we allocated,
+	 * memory is | beacon_data | head | tail |
+	 */
+	bcn->head = ((u8 *) bcn) + sizeof(*bcn);
+
+	/* fill in the head */
+	mgmt = (struct ieee80211_mgmt *) skb_put(skb, hdr_len);
+	memset(mgmt, 0, hdr_len);
+	mgmt->frame_control = cpu_to_le16(IEEE80211_FTYPE_MGMT |
+					  IEEE80211_STYPE_BEACON);
+	eth_broadcast_addr(mgmt->da);
+	memcpy(mgmt->sa, sdata->vif.addr, ETH_ALEN);
+	memcpy(mgmt->bssid, sdata->vif.addr, ETH_ALEN);

e.g. here

+	mgmt->u.beacon.beacon_int =
+		cpu_to_le16(sdata->vif.bss_conf.beacon_int);
+	mgmt->u.beacon.capab_info |= cpu_to_le16(
+		sdata->u.mesh.security ? WLAN_CAPABILITY_PRIVACY : 0);
+
+	pos = skb_put(skb, 2);
+	*pos++ = WLAN_EID_SSID;
+	*pos++ = 0x0;
+
+	if (ieee80211_add_srates_ie(sdata, skb, true, band) ||
+	    mesh_add_ds_params_ie(skb, sdata))
+		goto out_free;
+
+	bcn->head_len = skb->len;
+	memcpy(bcn->head, skb->data, bcn->head_len);
+
+	/* now the tail */
+	skb_trim(skb, 0);
+	bcn->tail = bcn->head + bcn->head_len;
+
+	if (ieee80211_add_ext_srates_ie(sdata, skb, true, band) ||
+	    mesh_add_rsn_ie(skb, sdata) ||
+	    mesh_add_ht_cap_ie(skb, sdata) ||
+	    mesh_add_ht_oper_ie(skb, sdata) ||
+	    mesh_add_meshid_ie(skb, sdata) ||
+	    mesh_add_meshconf_ie(skb, sdata) ||
+	    mesh_add_awake_window_ie(skb, sdata) ||
+	    mesh_add_vendor_ies(skb, sdata))
+		goto out_free;
+
+	bcn->tail_len = skb->len;
+	memcpy(bcn->tail, skb->data, bcn->tail_len);
+
+	dev_kfree_skb(skb);
+	rcu_assign_pointer(ifmsh->beacon, bcn);
+	return 0;
+out_free:
+	kfree(bcn);
+	dev_kfree_skb(skb);
+	return -ENOMEM;
+}
+
+static int
+ieee80211_mesh_rebuild_beacon(struct ieee80211_if_mesh *ifmsh)
+{
+	struct ieee80211_sub_if_data *sdata;
+	struct beacon_data *old_bcn;
+	int ret;
+	sdata = container_of(ifmsh, struct ieee80211_sub_if_data, u.mesh);
+
+	mutex_lock(&ifmsh->mtx);
+
+	old_bcn = rcu_dereference_protected(ifmsh->beacon,
+					    lockdep_is_held(&ifmsh->mtx));
+	ret = ieee80211_mesh_build_beacon(ifmsh);
+	if (ret)
+		/* just reuse old beacon */
+		goto out;
+
+	if (old_bcn)
+		kfree_rcu(old_bcn, rcu_head);
+out:
+	mutex_unlock(&ifmsh->mtx);
+	return ret;
+}
+
+void ieee80211_mbss_info_change_notify(struct ieee80211_sub_if_data *sdata,
+				       u32 changed)
+{
+	if (sdata->vif.bss_conf.enable_beacon &&
+	    (changed & (BSS_CHANGED_BEACON |
+			BSS_CHANGED_HT |
+			BSS_CHANGED_BASIC_RATES |
+			BSS_CHANGED_BEACON_INT)))
+		if (ieee80211_mesh_rebuild_beacon(&sdata->u.mesh))
+			return;
+	ieee80211_bss_info_change_notify(sdata, changed);
+	return;
+}
+
  void ieee80211_start_mesh(struct ieee80211_sub_if_data *sdata)
  {
  	struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
@@ -677,6 +810,11 @@ void ieee80211_start_mesh(struct ieee80211_sub_if_data *sdata)

  	changed |= ieee80211_mps_local_status_update(sdata);

+	if (ieee80211_mesh_build_beacon(ifmsh)) {
+		ieee80211_stop_mesh(sdata);
+		return;
+	}
+
  	ieee80211_bss_info_change_notify(sdata, changed);

  	netif_carrier_on(sdata->dev);
@@ -694,6 +832,8 @@ void ieee80211_stop_mesh(struct ieee80211_sub_if_data *sdata)
  	sdata->vif.bss_conf.enable_beacon = false;
  	clear_bit(SDATA_STATE_OFFCHANNEL_BEACON_STOPPED, &sdata->state);
  	ieee80211_bss_info_change_notify(sdata, BSS_CHANGED_BEACON_ENABLED);
+	kfree_rcu(ifmsh->beacon, rcu_head);
+	rcu_assign_pointer(ifmsh->beacon, NULL);

  	/* flush STAs and mpaths on this iface */
  	sta_info_flush(sdata);
@@ -883,6 +1023,8 @@ void ieee80211_mesh_init_sdata(struct ieee80211_sub_if_data *sdata)
  	skb_queue_head_init(&ifmsh->ps.bc_buf);
  	spin_lock_init(&ifmsh->mesh_preq_queue_lock);
  	spin_lock_init(&ifmsh->sync_offset_lock);
+	RCU_INIT_POINTER(ifmsh->beacon, NULL);
+	mutex_init(&ifmsh->mtx);

  	sdata->vif.bss_conf.bssid = zero_addr;
  }
diff --git a/net/mac80211/mesh.h b/net/mac80211/mesh.h
index 7ad035f..3ce00ba 100644
--- a/net/mac80211/mesh.h
+++ b/net/mac80211/mesh.h
@@ -243,6 +243,9 @@ void ieee80211_start_mesh(struct ieee80211_sub_if_data *sdata);
  void ieee80211_stop_mesh(struct ieee80211_sub_if_data *sdata);
  void ieee80211_mesh_root_setup(struct ieee80211_if_mesh *ifmsh);
  const struct ieee80211_mesh_sync_ops *ieee80211_mesh_sync_ops_get(u8 method);
+/* wrapper for ieee80211_bss_info_change_notify() */
+void ieee80211_mbss_info_change_notify(struct ieee80211_sub_if_data *sdata,
+				       u32 changed);

  /* mesh power save */
  u32 ieee80211_mps_local_status_update(struct ieee80211_sub_if_data *sdata);
diff --git a/net/mac80211/mesh_plink.c b/net/mac80211/mesh_plink.c
index a4c7a7e..13983b6 100644
--- a/net/mac80211/mesh_plink.c
+++ b/net/mac80211/mesh_plink.c
@@ -510,7 +510,7 @@ void mesh_neighbour_update(struct ieee80211_sub_if_data *sdata,
  	ieee80211_mps_frame_release(sta, elems);
  out:
  	rcu_read_unlock();
-	ieee80211_bss_info_change_notify(sdata, changed);
+	ieee80211_mbss_info_change_notify(sdata, changed);
  }

  static void mesh_plink_timer(unsigned long data)
@@ -1092,5 +1092,5 @@ void mesh_rx_plink_frame(struct ieee80211_sub_if_data *sdata, struct ieee80211_m
  	rcu_read_unlock();

  	if (changed)
-		ieee80211_bss_info_change_notify(sdata, changed);
+		ieee80211_mbss_info_change_notify(sdata, changed);
  }
diff --git a/net/mac80211/tx.c b/net/mac80211/tx.c
index f476aa6..0dabc8a 100644
--- a/net/mac80211/tx.c
+++ b/net/mac80211/tx.c
@@ -2446,71 +2446,26 @@ struct sk_buff *ieee80211_beacon_get_tim(struct ieee80211_hw *hw,
  		hdr->frame_control = cpu_to_le16(IEEE80211_FTYPE_MGMT |
  						 IEEE80211_STYPE_BEACON);
  	} else if (ieee80211_vif_is_mesh(&sdata->vif)) {
-		struct ieee80211_mgmt *mgmt;
  		struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
-		u8 *pos;
-		int hdr_len = offsetof(struct ieee80211_mgmt, u.beacon) +
-			      sizeof(mgmt->u.beacon);
+		struct beacon_data *bcn = rcu_dereference(ifmsh->beacon);

-#ifdef CONFIG_MAC80211_MESH
-		if (!sdata->u.mesh.mesh_id_len)
+		if (!bcn)
  			goto out;
-#endif

  		if (ifmsh->sync_ops)
  			ifmsh->sync_ops->adjust_tbtt(
  						sdata);

  		skb = dev_alloc_skb(local->tx_headroom +
-				    hdr_len +
-				    2 + /* NULL SSID */
-				    2 + 8 + /* supported rates */
-				    2 + 3 + /* DS params */
+				    bcn->head_len +
  				    256 + /* TIM IE */
-				    2 + (IEEE80211_MAX_SUPP_RATES - 8) +
-				    2 + sizeof(struct ieee80211_ht_cap) +
-				    2 + sizeof(struct ieee80211_ht_operation) +
-				    2 + sdata->u.mesh.mesh_id_len +
-				    2 + sizeof(struct ieee80211_meshconf_ie) +
-				    sdata->u.mesh.ie_len +
-				    2 + sizeof(__le16)); /* awake window */
+				    bcn->tail_len);
  		if (!skb)
  			goto out;
-
-		skb_reserve(skb, local->hw.extra_tx_headroom);
-		mgmt = (struct ieee80211_mgmt *) skb_put(skb, hdr_len);
-		memset(mgmt, 0, hdr_len);
-		mgmt->frame_control =
-		    cpu_to_le16(IEEE80211_FTYPE_MGMT | IEEE80211_STYPE_BEACON);
-		eth_broadcast_addr(mgmt->da);
-		memcpy(mgmt->sa, sdata->vif.addr, ETH_ALEN);
-		memcpy(mgmt->bssid, sdata->vif.addr, ETH_ALEN);
-		ieee80211_mps_set_frame_flags(sdata, NULL, (void *) mgmt);

as previously here

-		mgmt->u.beacon.beacon_int =
-			cpu_to_le16(sdata->vif.bss_conf.beacon_int);
-		mgmt->u.beacon.capab_info |= cpu_to_le16(
-			sdata->u.mesh.security ? WLAN_CAPABILITY_PRIVACY : 0);
-
-		pos = skb_put(skb, 2);
-		*pos++ = WLAN_EID_SSID;
-		*pos++ = 0x0;
-
-		band = chanctx_conf->def.chan->band;
-
-		if (ieee80211_add_srates_ie(sdata, skb, true, band) ||
-		    mesh_add_ds_params_ie(skb, sdata) ||
-		    ieee80211_beacon_add_tim(sdata, &ifmsh->ps, skb) ||
-		    ieee80211_add_ext_srates_ie(sdata, skb, true, band) ||
-		    mesh_add_rsn_ie(skb, sdata) ||
-		    mesh_add_ht_cap_ie(skb, sdata) ||
-		    mesh_add_ht_oper_ie(skb, sdata) ||
-		    mesh_add_meshid_ie(skb, sdata) ||
-		    mesh_add_meshconf_ie(skb, sdata) ||
-		    mesh_add_awake_window_ie(skb, sdata) ||
-		    mesh_add_vendor_ies(skb, sdata)) {
-			pr_err("o11s: couldn't add ies!\n");
-			goto out;
-		}
+		skb_reserve(skb, local->tx_headroom);
+		memcpy(skb_put(skb, bcn->head_len), bcn->head, bcn->head_len);
+		ieee80211_beacon_add_tim(sdata, &ifmsh->ps, skb);
+		memcpy(skb_put(skb, bcn->tail_len), bcn->tail, bcn->tail_len);
  	} else {
  		WARN_ON(1);
  		goto out;


--
To unsubscribe from this list: send the line "unsubscribe linux-wireless" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at  http://vger.kernel.org/majordomo-info.html


[Index of Archives]     [Linux Host AP]     [ATH6KL]     [Linux Wireless Personal Area Network]     [Linux Bluetooth]     [Linux Netdev]     [Kernel Newbies]     [Linux Kernel]     [IDE]     [Git]     [Netfilter]     [Bugtraq]     [Yosemite Hiking]     [MIPS Linux]     [ARM Linux]     [Linux RAID]

  Powered by Linux