#include "wme.h"
#include "rate.h"
-#define IEEE80211_TX_OK 0
-#define IEEE80211_TX_AGAIN 1
-#define IEEE80211_TX_PENDING 2
-
/* misc utils */
static __le16 ieee80211_duration(struct ieee80211_tx_data *tx, int group_addr,
return TX_CONTINUE;
}
-static int __ieee80211_tx(struct ieee80211_local *local,
- struct sk_buff **skbp,
- struct sta_info *sta,
- bool txpending)
+/*
+ * Returns false if the frame couldn't be transmitted but was queued instead.
+ */
+static bool __ieee80211_tx(struct ieee80211_local *local, struct sk_buff **skbp,
+ struct sta_info *sta, bool txpending)
{
struct sk_buff *skb = *skbp, *next;
struct ieee80211_tx_info *info;
struct ieee80211_sub_if_data *sdata;
unsigned long flags;
- int ret, len;
+ int len;
bool fragm = false;
while (skb) {
__le16 fc;
spin_lock_irqsave(&local->queue_stop_reason_lock, flags);
- ret = IEEE80211_TX_OK;
if (local->queue_stop_reasons[q] ||
- (!txpending && !skb_queue_empty(&local->pending[q])))
- ret = IEEE80211_TX_PENDING;
+ (!txpending && !skb_queue_empty(&local->pending[q]))) {
+ /*
+ * Since queue is stopped, queue up frames for later
+ * transmission from the tx-pending tasklet when the
+ * queue is woken again.
+ */
+
+ do {
+ next = skb->next;
+ skb->next = NULL;
+ /*
+ * NB: If txpending is true, next must already
+ * be NULL since we must've gone through this
+ * loop before already; therefore we can just
+ * queue the frame to the head without worrying
+ * about reordering of fragments.
+ */
+ if (unlikely(txpending))
+ __skb_queue_head(&local->pending[q],
+ skb);
+ else
+ __skb_queue_tail(&local->pending[q],
+ skb);
+ } while ((skb = next));
+
+ spin_unlock_irqrestore(&local->queue_stop_reason_lock,
+ flags);
+ return false;
+ }
spin_unlock_irqrestore(&local->queue_stop_reason_lock, flags);
- if (ret != IEEE80211_TX_OK)
- return ret;
info = IEEE80211_SKB_CB(skb);
info->control.sta = NULL;
fc = ((struct ieee80211_hdr *)skb->data)->frame_control;
- ret = drv_tx(local, skb);
- if (WARN_ON(ret != NETDEV_TX_OK && skb->len != len)) {
- dev_kfree_skb(skb);
- ret = NETDEV_TX_OK;
- }
- if (ret != NETDEV_TX_OK) {
- info->control.vif = &sdata->vif;
- return IEEE80211_TX_AGAIN;
- }
+ drv_tx(local, skb);
ieee80211_tpt_led_trig_tx(local, fc, len);
*skbp = skb = next;
fragm = true;
}
- return IEEE80211_TX_OK;
+ return true;
}
/*
return 0;
}
-static void ieee80211_tx(struct ieee80211_sub_if_data *sdata,
+/*
+ * Returns false if the frame couldn't be transmitted but was queued instead.
+ */
+static bool ieee80211_tx(struct ieee80211_sub_if_data *sdata,
struct sk_buff *skb, bool txpending)
{
struct ieee80211_local *local = sdata->local;
struct ieee80211_tx_data tx;
ieee80211_tx_result res_prepare;
struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
- struct sk_buff *next;
- unsigned long flags;
- int ret, retries;
u16 queue;
+ bool result = true;
queue = skb_get_queue_mapping(skb);
if (unlikely(skb->len < 10)) {
dev_kfree_skb(skb);
- return;
+ return true;
}
rcu_read_lock();
if (unlikely(res_prepare == TX_DROP)) {
dev_kfree_skb(skb);
- rcu_read_unlock();
- return;
+ goto out;
} else if (unlikely(res_prepare == TX_QUEUED)) {
- rcu_read_unlock();
- return;
+ goto out;
}
tx.channel = local->hw.conf.channel;
info->band = tx.channel->band;
- if (invoke_tx_handlers(&tx))
- goto out;
-
- retries = 0;
- retry:
- ret = __ieee80211_tx(local, &tx.skb, tx.sta, txpending);
- switch (ret) {
- case IEEE80211_TX_OK:
- break;
- case IEEE80211_TX_AGAIN:
- /*
- * Since there are no fragmented frames on A-MPDU
- * queues, there's no reason for a driver to reject
- * a frame there, warn and drop it.
- */
- if (WARN_ON(info->flags & IEEE80211_TX_CTL_AMPDU))
- goto drop;
- /* fall through */
- case IEEE80211_TX_PENDING:
- skb = tx.skb;
-
- spin_lock_irqsave(&local->queue_stop_reason_lock, flags);
-
- if (local->queue_stop_reasons[queue] ||
- !skb_queue_empty(&local->pending[queue])) {
- /*
- * if queue is stopped, queue up frames for later
- * transmission from the tasklet
- */
- do {
- next = skb->next;
- skb->next = NULL;
- if (unlikely(txpending))
- __skb_queue_head(&local->pending[queue],
- skb);
- else
- __skb_queue_tail(&local->pending[queue],
- skb);
- } while ((skb = next));
-
- spin_unlock_irqrestore(&local->queue_stop_reason_lock,
- flags);
- } else {
- /*
- * otherwise retry, but this is a race condition or
- * a driver bug (which we warn about if it persists)
- */
- spin_unlock_irqrestore(&local->queue_stop_reason_lock,
- flags);
-
- retries++;
- if (WARN(retries > 10, "tx refused but queue active\n"))
- goto drop;
- goto retry;
- }
- }
+ if (!invoke_tx_handlers(&tx))
+ result = __ieee80211_tx(local, &tx.skb, tx.sta, txpending);
out:
rcu_read_unlock();
- return;
-
- drop:
- rcu_read_unlock();
-
- skb = tx.skb;
- while (skb) {
- next = skb->next;
- dev_kfree_skb(skb);
- skb = next;
- }
+ return result;
}
/* device xmit handlers */
skb_queue_purge(&local->pending[i]);
}
+/*
+ * Returns false if the frame couldn't be transmitted but was queued instead,
+ * which in this case means re-queued -- take as an indication to stop sending
+ * more pending frames.
+ */
static bool ieee80211_tx_pending_skb(struct ieee80211_local *local,
struct sk_buff *skb)
{
struct ieee80211_sub_if_data *sdata;
struct sta_info *sta;
struct ieee80211_hdr *hdr;
- int ret;
- bool result = true;
+ bool result;
sdata = vif_to_sdata(info->control.vif);
if (info->flags & IEEE80211_TX_INTFL_NEED_TXPROCESSING) {
- ieee80211_tx(sdata, skb, true);
+ result = ieee80211_tx(sdata, skb, true);
} else {
hdr = (struct ieee80211_hdr *)skb->data;
sta = sta_info_get(sdata, hdr->addr1);
- ret = __ieee80211_tx(local, &skb, sta, true);
- if (ret != IEEE80211_TX_OK)
- result = false;
+ result = __ieee80211_tx(local, &skb, sta, true);
}
return result;
flags);
txok = ieee80211_tx_pending_skb(local, skb);
- if (!txok)
- __skb_queue_head(&local->pending[i], skb);
spin_lock_irqsave(&local->queue_stop_reason_lock,
flags);
if (!txok)
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