mac80211: cache mesh beacon

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@cozybit.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

1 files changed, 8 insertions, 53 deletions

diff --git a/net/mac80211/tx.c b/net/mac80211/tx.c
index 7d8c629f1e6a..fe644f91ae05 100644
--- a/net/mac80211/tx.c
+++ b/net/mac80211/tx.c
@@ -2444,71 +2444,26 @@ 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);
-		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;