* @IEEE80211_TX_INTFL_RCALGO: mac80211 internal flag, do not test or
* set this flag in the driver; indicates that the rate control
* algorithm was used and should be notified of TX status
+ * @IEEE80211_TX_INTFL_NEED_TXPROCESSING: completely internal to mac80211,
+ * used to indicate that a pending frame requires TX processing before
+ * it can be sent out.
*/
enum mac80211_tx_control_flags {
IEEE80211_TX_CTL_REQ_TX_STATUS = BIT(0),
IEEE80211_TX_STAT_AMPDU_NO_BACK = BIT(11),
IEEE80211_TX_CTL_RATE_CTRL_PROBE = BIT(12),
IEEE80211_TX_INTFL_RCALGO = BIT(13),
+ IEEE80211_TX_INTFL_NEED_TXPROCESSING = BIT(14),
};
/**
state = &sta->ampdu_mlme.tid_state_tx[tid];
if (local->hw.ampdu_queues) {
- if (initiator) {
- /*
- * Stop the AC queue to avoid issues where we send
- * unaggregated frames already before the delba.
- */
- ieee80211_stop_queue_by_reason(&local->hw,
- local->hw.queues + sta->tid_to_tx_q[tid],
- IEEE80211_QUEUE_STOP_REASON_AGGREGATION);
- }
-
/*
* Pretend the driver woke the queue, just in case
* it disabled it before the session was stopped.
/* HW shall not deny going back to legacy */
if (WARN_ON(ret)) {
*state = HT_AGG_STATE_OPERATIONAL;
+ /*
+ * We may have pending packets get stuck in this case...
+ * Not bothering with a workaround for now.
+ */
}
return ret;
ra, tid);
#endif /* CONFIG_MAC80211_HT_DEBUG */
- if (hw->ampdu_queues && ieee80211_ac_from_tid(tid) == 0) {
-#ifdef CONFIG_MAC80211_HT_DEBUG
- printk(KERN_DEBUG "rejecting on voice AC\n");
-#endif
- return -EINVAL;
- }
-
rcu_read_lock();
sta = sta_info_get(local, ra);
}
spin_lock_bh(&sta->lock);
+ spin_lock(&local->ampdu_lock);
sdata = sta->sdata;
ret = -ENOSPC;
goto err_unlock_sta;
}
-
- /*
- * If we successfully allocate the session, we can't have
- * anything going on on the queue this TID maps into, so
- * stop it for now. This is a "virtual" stop using the same
- * mechanism that drivers will use.
- *
- * XXX: queue up frames for this session in the sta_info
- * struct instead to avoid hitting all other STAs.
- */
- ieee80211_stop_queue_by_reason(
- &local->hw, hw->queues + qn,
- IEEE80211_QUEUE_STOP_REASON_AGGREGATION);
}
+ /*
+ * While we're asking the driver about the aggregation,
+ * stop the AC queue so that we don't have to worry
+ * about frames that came in while we were doing that,
+ * which would require us to put them to the AC pending
+ * afterwards which just makes the code more complex.
+ */
+ ieee80211_stop_queue_by_reason(
+ &local->hw, ieee80211_ac_from_tid(tid),
+ IEEE80211_QUEUE_STOP_REASON_AGGREGATION);
+
/* prepare A-MPDU MLME for Tx aggregation */
sta->ampdu_mlme.tid_tx[tid] =
kmalloc(sizeof(struct tid_ampdu_tx), GFP_ATOMIC);
goto err_return_queue;
}
+ skb_queue_head_init(&sta->ampdu_mlme.tid_tx[tid]->pending);
+
/* Tx timer */
sta->ampdu_mlme.tid_tx[tid]->addba_resp_timer.function =
sta_addba_resp_timer_expired;
}
sta->tid_to_tx_q[tid] = qn;
+ /* Driver vetoed or OKed, but we can take packets again now */
+ ieee80211_wake_queue_by_reason(
+ &local->hw, ieee80211_ac_from_tid(tid),
+ IEEE80211_QUEUE_STOP_REASON_AGGREGATION);
+
+ spin_unlock(&local->ampdu_lock);
spin_unlock_bh(&sta->lock);
/* send an addBA request */
sta->ampdu_mlme.tid_tx[tid] = NULL;
err_return_queue:
if (qn >= 0) {
- /* We failed, so start queue again right away. */
- ieee80211_wake_queue_by_reason(hw, hw->queues + qn,
- IEEE80211_QUEUE_STOP_REASON_AGGREGATION);
/* give queue back to pool */
spin_lock(&local->queue_stop_reason_lock);
local->ampdu_ac_queue[qn] = -1;
spin_unlock(&local->queue_stop_reason_lock);
}
+ ieee80211_wake_queue_by_reason(
+ &local->hw, ieee80211_ac_from_tid(tid),
+ IEEE80211_QUEUE_STOP_REASON_AGGREGATION);
err_unlock_sta:
+ spin_unlock(&local->ampdu_lock);
spin_unlock_bh(&sta->lock);
unlock:
rcu_read_unlock();
}
EXPORT_SYMBOL(ieee80211_start_tx_ba_session);
+/*
+ * splice packets from the STA's pending to the local pending,
+ * requires a call to ieee80211_agg_splice_finish and holding
+ * local->ampdu_lock across both calls.
+ */
+static void ieee80211_agg_splice_packets(struct ieee80211_local *local,
+ struct sta_info *sta, u16 tid)
+{
+ unsigned long flags;
+ u16 queue = ieee80211_ac_from_tid(tid);
+
+ ieee80211_stop_queue_by_reason(
+ &local->hw, queue,
+ IEEE80211_QUEUE_STOP_REASON_AGGREGATION);
+
+ if (!skb_queue_empty(&sta->ampdu_mlme.tid_tx[tid]->pending)) {
+ spin_lock_irqsave(&local->queue_stop_reason_lock, flags);
+ /* mark queue as pending, it is stopped already */
+ __set_bit(IEEE80211_QUEUE_STOP_REASON_PENDING,
+ &local->queue_stop_reasons[queue]);
+ /* copy over remaining packets */
+ skb_queue_splice_tail_init(
+ &sta->ampdu_mlme.tid_tx[tid]->pending,
+ &local->pending[queue]);
+ spin_unlock_irqrestore(&local->queue_stop_reason_lock, flags);
+ }
+}
+
+static void ieee80211_agg_splice_finish(struct ieee80211_local *local,
+ struct sta_info *sta, u16 tid)
+{
+ u16 queue = ieee80211_ac_from_tid(tid);
+
+ ieee80211_wake_queue_by_reason(
+ &local->hw, queue,
+ IEEE80211_QUEUE_STOP_REASON_AGGREGATION);
+}
+
+/* caller must hold sta->lock */
static void ieee80211_agg_tx_operational(struct ieee80211_local *local,
struct sta_info *sta, u16 tid)
{
printk(KERN_DEBUG "Aggregation is on for tid %d \n", tid);
#endif
- if (local->hw.ampdu_queues) {
- /*
- * Wake up the A-MPDU queue, we stopped it earlier,
- * this will in turn wake the entire AC.
- */
- ieee80211_wake_queue_by_reason(&local->hw,
- local->hw.queues + sta->tid_to_tx_q[tid],
- IEEE80211_QUEUE_STOP_REASON_AGGREGATION);
- }
+ spin_lock(&local->ampdu_lock);
+ ieee80211_agg_splice_packets(local, sta, tid);
+ /*
+ * NB: we rely on sta->lock being taken in the TX
+ * processing here when adding to the pending queue,
+ * otherwise we could only change the state of the
+ * session to OPERATIONAL _here_.
+ */
+ ieee80211_agg_splice_finish(local, sta, tid);
+ spin_unlock(&local->ampdu_lock);
local->ops->ampdu_action(&local->hw, IEEE80211_AMPDU_TX_OPERATIONAL,
&sta->sta, tid, NULL);
WLAN_BACK_INITIATOR, WLAN_REASON_QSTA_NOT_USE);
spin_lock_bh(&sta->lock);
+ spin_lock(&local->ampdu_lock);
- if (*state & HT_AGG_STATE_INITIATOR_MSK &&
- hw->ampdu_queues) {
- /*
- * Wake up this queue, we stopped it earlier,
- * this will in turn wake the entire AC.
- */
- ieee80211_wake_queue_by_reason(hw,
- hw->queues + sta->tid_to_tx_q[tid],
- IEEE80211_QUEUE_STOP_REASON_AGGREGATION);
- }
+ ieee80211_agg_splice_packets(local, sta, tid);
*state = HT_AGG_STATE_IDLE;
+ /* from now on packets are no longer put onto sta->pending */
sta->ampdu_mlme.addba_req_num[tid] = 0;
kfree(sta->ampdu_mlme.tid_tx[tid]);
sta->ampdu_mlme.tid_tx[tid] = NULL;
+
+ ieee80211_agg_splice_finish(local, sta, tid);
+
+ spin_unlock(&local->ampdu_lock);
spin_unlock_bh(&sta->lock);
rcu_read_unlock();
struct sk_buff_head pending[IEEE80211_MAX_QUEUES];
struct tasklet_struct tx_pending_tasklet;
+ /*
+ * This lock is used to prevent concurrent A-MPDU
+ * session start/stop processing, this thus also
+ * synchronises the ->ampdu_action() callback to
+ * drivers and limits it to one at a time.
+ */
+ spinlock_t ampdu_lock;
+
/* number of interfaces with corresponding IFF_ flags */
atomic_t iff_allmultis, iff_promiscs;
skb_queue_head_init(&local->skb_queue);
skb_queue_head_init(&local->skb_queue_unreliable);
+ spin_lock_init(&local->ampdu_lock);
+
return local_to_hw(local);
}
EXPORT_SYMBOL(ieee80211_alloc_hw);
tid_tx = sta->ampdu_mlme.tid_tx[i];
if (tid_tx) {
del_timer_sync(&tid_tx->addba_resp_timer);
+ /*
+ * STA removed while aggregation session being
+ * started? Bit odd, but purge frames anyway.
+ */
+ skb_queue_purge(&tid_tx->pending);
kfree(tid_tx);
}
}
* struct tid_ampdu_tx - TID aggregation information (Tx).
*
* @addba_resp_timer: timer for peer's response to addba request
+ * @pending: pending frames queue -- use sta's spinlock to protect
* @ssn: Starting Sequence Number expected to be aggregated.
* @dialog_token: dialog token for aggregation session
*/
struct tid_ampdu_tx {
struct timer_list addba_resp_timer;
+ struct sk_buff_head pending;
u16 ssn;
u8 dialog_token;
};
struct ieee80211_hdr *hdr;
struct ieee80211_sub_if_data *sdata;
struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
-
int hdrlen, tid;
u8 *qc, *state;
+ bool queued = false;
memset(tx, 0, sizeof(*tx));
tx->skb = skb;
*/
}
+ /*
+ * If this flag is set to true anywhere, and we get here,
+ * we are doing the needed processing, so remove the flag
+ * now.
+ */
+ info->flags &= ~IEEE80211_TX_INTFL_NEED_TXPROCESSING;
+
hdr = (struct ieee80211_hdr *) skb->data;
tx->sta = sta_info_get(local, hdr->addr1);
- if (tx->sta && ieee80211_is_data_qos(hdr->frame_control)) {
+ if (tx->sta && ieee80211_is_data_qos(hdr->frame_control) &&
+ (local->hw.flags & IEEE80211_HW_AMPDU_AGGREGATION)) {
unsigned long flags;
+ struct tid_ampdu_tx *tid_tx;
+
qc = ieee80211_get_qos_ctl(hdr);
tid = *qc & IEEE80211_QOS_CTL_TID_MASK;
spin_lock_irqsave(&tx->sta->lock, flags);
+ /*
+ * XXX: This spinlock could be fairly expensive, but see the
+ * comment in agg-tx.c:ieee80211_agg_tx_operational().
+ * One way to solve this would be to do something RCU-like
+ * for managing the tid_tx struct and using atomic bitops
+ * for the actual state -- by introducing an actual
+ * 'operational' bit that would be possible. It would
+ * require changing ieee80211_agg_tx_operational() to
+ * set that bit, and changing the way tid_tx is managed
+ * everywhere, including races between that bit and
+ * tid_tx going away (tid_tx being added can be easily
+ * committed to memory before the 'operational' bit).
+ */
+ tid_tx = tx->sta->ampdu_mlme.tid_tx[tid];
state = &tx->sta->ampdu_mlme.tid_state_tx[tid];
- if (*state == HT_AGG_STATE_OPERATIONAL)
+ if (*state == HT_AGG_STATE_OPERATIONAL) {
info->flags |= IEEE80211_TX_CTL_AMPDU;
+ } else if (*state != HT_AGG_STATE_IDLE) {
+ /* in progress */
+ queued = true;
+ info->flags |= IEEE80211_TX_INTFL_NEED_TXPROCESSING;
+ __skb_queue_tail(&tid_tx->pending, skb);
+ }
spin_unlock_irqrestore(&tx->sta->lock, flags);
+
+ if (unlikely(queued))
+ return TX_QUEUED;
}
if (is_multicast_ether_addr(hdr->addr1)) {
}
if (unlikely(!dev))
return -ENODEV;
- /* initialises tx with control */
+ /*
+ * initialises tx with control
+ *
+ * return value is safe to ignore here because this function
+ * can only be invoked for multicast frames
+ *
+ * XXX: clean up
+ */
__ieee80211_tx_prepare(tx, skb, dev);
dev_put(dev);
return 0;
return 0;
}
-static int ieee80211_tx(struct net_device *dev, struct sk_buff *skb)
+static void ieee80211_tx(struct net_device *dev, struct sk_buff *skb,
+ bool txpending)
{
struct ieee80211_local *local = wdev_priv(dev->ieee80211_ptr);
struct sta_info *sta;
queue = skb_get_queue_mapping(skb);
- WARN_ON(!skb_queue_empty(&local->pending[queue]));
+ WARN_ON(!txpending && !skb_queue_empty(&local->pending[queue]));
if (unlikely(skb->len < 10)) {
dev_kfree_skb(skb);
- return 0;
+ return;
}
rcu_read_lock();
/* initialises tx */
res_prepare = __ieee80211_tx_prepare(&tx, skb, dev);
- if (res_prepare == TX_DROP) {
+ if (unlikely(res_prepare == TX_DROP)) {
dev_kfree_skb(skb);
rcu_read_unlock();
- return 0;
+ return;
+ } else if (unlikely(res_prepare == TX_QUEUED)) {
+ rcu_read_unlock();
+ return;
}
sta = tx.sta;
do {
next = skb->next;
skb->next = NULL;
- skb_queue_tail(&local->pending[queue], skb);
+ if (unlikely(txpending))
+ skb_queue_head(&local->pending[queue],
+ skb);
+ else
+ skb_queue_tail(&local->pending[queue],
+ skb);
} while ((skb = next));
/*
}
out:
rcu_read_unlock();
- return 0;
+ return;
drop:
rcu_read_unlock();
dev_kfree_skb(skb);
skb = next;
}
- return 0;
}
/* device xmit handlers */
FOUND_SDATA,
UNKNOWN_ADDRESS,
} monitor_iface = NOT_MONITOR;
- int ret;
if (skb->iif)
odev = dev_get_by_index(&init_net, skb->iif);
"originating device\n", dev->name);
#endif
dev_kfree_skb(skb);
- return 0;
+ return NETDEV_TX_OK;
}
if ((local->hw.flags & IEEE80211_HW_PS_NULLFUNC_STACK) &&
else
if (mesh_nexthop_lookup(skb, osdata)) {
dev_put(odev);
- return 0;
+ return NETDEV_TX_OK;
}
if (memcmp(odev->dev_addr, hdr->addr4, ETH_ALEN) != 0)
IEEE80211_IFSTA_MESH_CTR_INC(&osdata->u.mesh,
if (ieee80211_skb_resize(osdata->local, skb, headroom, may_encrypt)) {
dev_kfree_skb(skb);
dev_put(odev);
- return 0;
+ return NETDEV_TX_OK;
}
if (osdata->vif.type == NL80211_IFTYPE_AP_VLAN)
u.ap);
if (likely(monitor_iface != UNKNOWN_ADDRESS))
info->control.vif = &osdata->vif;
- ret = ieee80211_tx(odev, skb);
+
+ ieee80211_tx(odev, skb, false);
dev_put(odev);
- return ret;
+ return NETDEV_TX_OK;
}
int ieee80211_monitor_start_xmit(struct sk_buff *skb,
skb_queue_purge(&local->pending[i]);
}
+static bool ieee80211_tx_pending_skb(struct ieee80211_local *local,
+ struct sk_buff *skb)
+{
+ struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
+ struct ieee80211_sub_if_data *sdata;
+ struct sta_info *sta;
+ struct ieee80211_hdr *hdr;
+ struct net_device *dev;
+ int ret;
+ bool result = true;
+
+ /* does interface still exist? */
+ dev = dev_get_by_index(&init_net, skb->iif);
+ if (!dev) {
+ dev_kfree_skb(skb);
+ return true;
+ }
+
+ /* validate info->control.vif against skb->iif */
+ sdata = IEEE80211_DEV_TO_SUB_IF(dev);
+ if (sdata->vif.type == NL80211_IFTYPE_AP_VLAN)
+ sdata = container_of(sdata->bss,
+ struct ieee80211_sub_if_data,
+ u.ap);
+
+ if (unlikely(info->control.vif && info->control.vif != &sdata->vif)) {
+ dev_kfree_skb(skb);
+ result = true;
+ goto out;
+ }
+
+ if (info->flags & IEEE80211_TX_INTFL_NEED_TXPROCESSING) {
+ ieee80211_tx(dev, skb, true);
+ } else {
+ hdr = (struct ieee80211_hdr *)skb->data;
+ sta = sta_info_get(local, hdr->addr1);
+
+ ret = __ieee80211_tx(local, &skb, sta);
+ if (ret != IEEE80211_TX_OK)
+ result = false;
+ }
+
+ out:
+ dev_put(dev);
+
+ return result;
+}
+
/*
* Transmit all pending packets. Called from tasklet, locks master device
* TX lock so that no new packets can come in.
{
struct ieee80211_local *local = (struct ieee80211_local *)data;
struct net_device *dev = local->mdev;
- struct ieee80211_hdr *hdr;
unsigned long flags;
- int i, ret;
+ int i;
bool next;
rcu_read_lock();
while (!skb_queue_empty(&local->pending[i])) {
struct sk_buff *skb = skb_dequeue(&local->pending[i]);
- struct sta_info *sta;
-
- hdr = (struct ieee80211_hdr *)skb->data;
- sta = sta_info_get(local, hdr->addr1);
- ret = __ieee80211_tx(local, &skb, sta);
- if (ret != IEEE80211_TX_OK) {
+ if (!ieee80211_tx_pending_skb(local, skb)) {
skb_queue_head(&local->pending[i], skb);
break;
}
projects / linux-platform-drivers-x86.git / commitdiff