mac80211: 802.11p OCB mode support
This patch adds 802.11p OCB (Outside the Context of a BSS) mode
support.
When communicating in OCB mode a mandatory wildcard BSSID
(48 '1' bits) is used.
The EDCA parameters handling function was changed to support
802.11p specific values.
The insertion of a newly discovered STAs is done in the similar way
as in the IBSS mode -- through the deferred insertion.
The OCB mode uses a periodic 'housekeeping task' for expiration of
disconnected STAs (in the similar manner as in the MESH mode).
New Kconfig option for verbose OCB debugging outputs is added.
Signed-off-by: Rostislav Lisovy <rostislav.lisovy@fel.cvut.cz>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
diff --git a/net/mac80211/ocb.c b/net/mac80211/ocb.c
new file mode 100644
index 0000000..358d5f9
--- /dev/null
+++ b/net/mac80211/ocb.c
@@ -0,0 +1,250 @@
+/*
+ * OCB mode implementation
+ *
+ * Copyright: (c) 2014 Czech Technical University in Prague
+ * (c) 2014 Volkswagen Group Research
+ * Author: Rostislav Lisovy <rostislav.lisovy@fel.cvut.cz>
+ * Funded by: Volkswagen Group Research
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+
+#include <linux/delay.h>
+#include <linux/if_ether.h>
+#include <linux/skbuff.h>
+#include <linux/if_arp.h>
+#include <linux/etherdevice.h>
+#include <linux/rtnetlink.h>
+#include <net/mac80211.h>
+#include <asm/unaligned.h>
+
+#include "ieee80211_i.h"
+#include "driver-ops.h"
+#include "rate.h"
+
+#define IEEE80211_OCB_HOUSEKEEPING_INTERVAL (60 * HZ)
+#define IEEE80211_OCB_PEER_INACTIVITY_LIMIT (240 * HZ)
+#define IEEE80211_OCB_MAX_STA_ENTRIES 128
+
+/**
+ * enum ocb_deferred_task_flags - mac80211 OCB deferred tasks
+ * @OCB_WORK_HOUSEKEEPING: run the periodic OCB housekeeping tasks
+ *
+ * These flags are used in @wrkq_flags field of &struct ieee80211_if_ocb
+ */
+enum ocb_deferred_task_flags {
+ OCB_WORK_HOUSEKEEPING,
+};
+
+void ieee80211_ocb_rx_no_sta(struct ieee80211_sub_if_data *sdata,
+ const u8 *bssid, const u8 *addr,
+ u32 supp_rates)
+{
+ struct ieee80211_if_ocb *ifocb = &sdata->u.ocb;
+ struct ieee80211_local *local = sdata->local;
+ struct ieee80211_chanctx_conf *chanctx_conf;
+ struct ieee80211_supported_band *sband;
+ enum nl80211_bss_scan_width scan_width;
+ struct sta_info *sta;
+ int band;
+
+ /* XXX: Consider removing the least recently used entry and
+ * allow new one to be added.
+ */
+ if (local->num_sta >= IEEE80211_OCB_MAX_STA_ENTRIES) {
+ net_info_ratelimited("%s: No room for a new OCB STA entry %pM\n",
+ sdata->name, addr);
+ return;
+ }
+
+ ocb_dbg(sdata, "Adding new OCB station %pM\n", addr);
+
+ rcu_read_lock();
+ chanctx_conf = rcu_dereference(sdata->vif.chanctx_conf);
+ if (WARN_ON_ONCE(!chanctx_conf)) {
+ rcu_read_unlock();
+ return;
+ }
+ band = chanctx_conf->def.chan->band;
+ scan_width = cfg80211_chandef_to_scan_width(&chanctx_conf->def);
+ rcu_read_unlock();
+
+ sta = sta_info_alloc(sdata, addr, GFP_ATOMIC);
+ if (!sta)
+ return;
+
+ sta->last_rx = jiffies;
+
+ /* Add only mandatory rates for now */
+ sband = local->hw.wiphy->bands[band];
+ sta->sta.supp_rates[band] =
+ ieee80211_mandatory_rates(sband, scan_width);
+
+ spin_lock(&ifocb->incomplete_lock);
+ list_add(&sta->list, &ifocb->incomplete_stations);
+ spin_unlock(&ifocb->incomplete_lock);
+ ieee80211_queue_work(&local->hw, &sdata->work);
+}
+
+static struct sta_info *ieee80211_ocb_finish_sta(struct sta_info *sta)
+ __acquires(RCU)
+{
+ struct ieee80211_sub_if_data *sdata = sta->sdata;
+ u8 addr[ETH_ALEN];
+
+ memcpy(addr, sta->sta.addr, ETH_ALEN);
+
+ ocb_dbg(sdata, "Adding new IBSS station %pM (dev=%s)\n",
+ addr, sdata->name);
+
+ sta_info_move_state(sta, IEEE80211_STA_AUTH);
+ sta_info_move_state(sta, IEEE80211_STA_ASSOC);
+ sta_info_move_state(sta, IEEE80211_STA_AUTHORIZED);
+
+ rate_control_rate_init(sta);
+
+ /* If it fails, maybe we raced another insertion? */
+ if (sta_info_insert_rcu(sta))
+ return sta_info_get(sdata, addr);
+ return sta;
+}
+
+static void ieee80211_ocb_housekeeping(struct ieee80211_sub_if_data *sdata)
+{
+ struct ieee80211_if_ocb *ifocb = &sdata->u.ocb;
+
+ ocb_dbg(sdata, "Running ocb housekeeping\n");
+
+ ieee80211_sta_expire(sdata, IEEE80211_OCB_PEER_INACTIVITY_LIMIT);
+
+ mod_timer(&ifocb->housekeeping_timer,
+ round_jiffies(jiffies + IEEE80211_OCB_HOUSEKEEPING_INTERVAL));
+}
+
+void ieee80211_ocb_work(struct ieee80211_sub_if_data *sdata)
+{
+ struct ieee80211_if_ocb *ifocb = &sdata->u.ocb;
+ struct sta_info *sta;
+
+ if (ifocb->joined != true)
+ return;
+
+ sdata_lock(sdata);
+
+ spin_lock_bh(&ifocb->incomplete_lock);
+ while (!list_empty(&ifocb->incomplete_stations)) {
+ sta = list_first_entry(&ifocb->incomplete_stations,
+ struct sta_info, list);
+ list_del(&sta->list);
+ spin_unlock_bh(&ifocb->incomplete_lock);
+
+ ieee80211_ocb_finish_sta(sta);
+ rcu_read_unlock();
+ spin_lock_bh(&ifocb->incomplete_lock);
+ }
+ spin_unlock_bh(&ifocb->incomplete_lock);
+
+ if (test_and_clear_bit(OCB_WORK_HOUSEKEEPING, &ifocb->wrkq_flags))
+ ieee80211_ocb_housekeeping(sdata);
+
+ sdata_unlock(sdata);
+}
+
+static void ieee80211_ocb_housekeeping_timer(unsigned long data)
+{
+ struct ieee80211_sub_if_data *sdata = (void *)data;
+ struct ieee80211_local *local = sdata->local;
+ struct ieee80211_if_ocb *ifocb = &sdata->u.ocb;
+
+ set_bit(OCB_WORK_HOUSEKEEPING, &ifocb->wrkq_flags);
+
+ ieee80211_queue_work(&local->hw, &sdata->work);
+}
+
+void ieee80211_ocb_setup_sdata(struct ieee80211_sub_if_data *sdata)
+{
+ struct ieee80211_if_ocb *ifocb = &sdata->u.ocb;
+
+ setup_timer(&ifocb->housekeeping_timer,
+ ieee80211_ocb_housekeeping_timer,
+ (unsigned long)sdata);
+ INIT_LIST_HEAD(&ifocb->incomplete_stations);
+ spin_lock_init(&ifocb->incomplete_lock);
+}
+
+int ieee80211_ocb_join(struct ieee80211_sub_if_data *sdata,
+ struct ocb_setup *setup)
+{
+ struct ieee80211_local *local = sdata->local;
+ struct ieee80211_if_ocb *ifocb = &sdata->u.ocb;
+ u32 changed = BSS_CHANGED_OCB;
+ int err;
+
+ if (ifocb->joined == true)
+ return -EINVAL;
+
+ sdata->flags |= IEEE80211_SDATA_OPERATING_GMODE;
+ sdata->smps_mode = IEEE80211_SMPS_OFF;
+ sdata->needed_rx_chains = sdata->local->rx_chains;
+
+ mutex_lock(&sdata->local->mtx);
+ err = ieee80211_vif_use_channel(sdata, &setup->chandef,
+ IEEE80211_CHANCTX_SHARED);
+ mutex_unlock(&sdata->local->mtx);
+ if (err)
+ return err;
+
+ ieee80211_bss_info_change_notify(sdata, changed);
+
+ ifocb->joined = true;
+
+ set_bit(OCB_WORK_HOUSEKEEPING, &ifocb->wrkq_flags);
+ ieee80211_queue_work(&local->hw, &sdata->work);
+
+ netif_carrier_on(sdata->dev);
+ return 0;
+}
+
+int ieee80211_ocb_leave(struct ieee80211_sub_if_data *sdata)
+{
+ struct ieee80211_if_ocb *ifocb = &sdata->u.ocb;
+ struct ieee80211_local *local = sdata->local;
+ struct sta_info *sta;
+
+ ifocb->joined = false;
+ sta_info_flush(sdata);
+
+ spin_lock_bh(&ifocb->incomplete_lock);
+ while (!list_empty(&ifocb->incomplete_stations)) {
+ sta = list_first_entry(&ifocb->incomplete_stations,
+ struct sta_info, list);
+ list_del(&sta->list);
+ spin_unlock_bh(&ifocb->incomplete_lock);
+
+ sta_info_free(local, sta);
+ spin_lock_bh(&ifocb->incomplete_lock);
+ }
+ spin_unlock_bh(&ifocb->incomplete_lock);
+
+ netif_carrier_off(sdata->dev);
+ clear_bit(SDATA_STATE_OFFCHANNEL, &sdata->state);
+ ieee80211_bss_info_change_notify(sdata, BSS_CHANGED_OCB);
+
+ mutex_lock(&sdata->local->mtx);
+ ieee80211_vif_release_channel(sdata);
+ mutex_unlock(&sdata->local->mtx);
+
+ skb_queue_purge(&sdata->skb_queue);
+
+ del_timer_sync(&sdata->u.ocb.housekeeping_timer);
+ /* If the timer fired while we waited for it, it will have
+ * requeued the work. Now the work will be running again
+ * but will not rearm the timer again because it checks
+ * whether we are connected to the network or not -- at this
+ * point we shouldn't be anymore.
+ */
+
+ return 0;
+}