iwlwifi: error checking for number of tfds in queue
When receive reply_tx and ready to decrement the count for number of
tfds in queue, do error checking to prevent error condition and
tfds_in_queue become negative number.
Signed-off-by: Wey-Yi Guy <wey-yi.w.guy@intel.com>
Signed-off-by: Reinette Chatre <reinette.chatre@intel.com>
CC: stable@kernel.org
Signed-off-by: John W. Linville <linville@tuxdriver.com>
diff --git a/drivers/net/wireless/iwlwifi/iwl-4965.c b/drivers/net/wireless/iwlwifi/iwl-4965.c
index 9b4b8b5..3146281 100644
--- a/drivers/net/wireless/iwlwifi/iwl-4965.c
+++ b/drivers/net/wireless/iwlwifi/iwl-4965.c
@@ -2008,7 +2008,7 @@
IWL_DEBUG_TX_REPLY(priv, "Retry scheduler reclaim scd_ssn "
"%d index %d\n", scd_ssn , index);
freed = iwl_tx_queue_reclaim(priv, txq_id, index);
- priv->stations[sta_id].tid[tid].tfds_in_queue -= freed;
+ iwl_free_tfds_in_queue(priv, sta_id, tid, freed);
if (priv->mac80211_registered &&
(iwl_queue_space(&txq->q) > txq->q.low_mark) &&
diff --git a/drivers/net/wireless/iwlwifi/iwl-5000.c b/drivers/net/wireless/iwlwifi/iwl-5000.c
index de45f30..f27c514 100644
--- a/drivers/net/wireless/iwlwifi/iwl-5000.c
+++ b/drivers/net/wireless/iwlwifi/iwl-5000.c
@@ -1125,7 +1125,7 @@
scd_ssn , index, txq_id, txq->swq_id);
freed = iwl_tx_queue_reclaim(priv, txq_id, index);
- priv->stations[sta_id].tid[tid].tfds_in_queue -= freed;
+ iwl_free_tfds_in_queue(priv, sta_id, tid, freed);
if (priv->mac80211_registered &&
(iwl_queue_space(&txq->q) > txq->q.low_mark) &&
@@ -1154,7 +1154,7 @@
freed = iwl_tx_queue_reclaim(priv, txq_id, index);
if (ieee80211_is_data_qos(tx_resp->frame_ctrl))
- priv->stations[sta_id].tid[tid].tfds_in_queue -= freed;
+ iwl_free_tfds_in_queue(priv, sta_id, tid, freed);
if (priv->mac80211_registered &&
(iwl_queue_space(&txq->q) > txq->q.low_mark))
diff --git a/drivers/net/wireless/iwlwifi/iwl-core.h b/drivers/net/wireless/iwlwifi/iwl-core.h
index 675b7df..fe37d6a 100644
--- a/drivers/net/wireless/iwlwifi/iwl-core.h
+++ b/drivers/net/wireless/iwlwifi/iwl-core.h
@@ -446,6 +446,8 @@
int iwl_hw_tx_queue_init(struct iwl_priv *priv,
struct iwl_tx_queue *txq);
int iwl_txq_update_write_ptr(struct iwl_priv *priv, struct iwl_tx_queue *txq);
+void iwl_free_tfds_in_queue(struct iwl_priv *priv,
+ int sta_id, int tid, int freed);
int iwl_tx_queue_init(struct iwl_priv *priv, struct iwl_tx_queue *txq,
int slots_num, u32 txq_id);
void iwl_tx_queue_free(struct iwl_priv *priv, int txq_id);
diff --git a/drivers/net/wireless/iwlwifi/iwl-tx.c b/drivers/net/wireless/iwlwifi/iwl-tx.c
index 87ce2bd..72136c8 100644
--- a/drivers/net/wireless/iwlwifi/iwl-tx.c
+++ b/drivers/net/wireless/iwlwifi/iwl-tx.c
@@ -120,6 +120,20 @@
EXPORT_SYMBOL(iwl_txq_update_write_ptr);
+void iwl_free_tfds_in_queue(struct iwl_priv *priv,
+ int sta_id, int tid, int freed)
+{
+ if (priv->stations[sta_id].tid[tid].tfds_in_queue >= freed)
+ priv->stations[sta_id].tid[tid].tfds_in_queue -= freed;
+ else {
+ IWL_ERR(priv, "free more than tfds_in_queue (%u:%d)\n",
+ priv->stations[sta_id].tid[tid].tfds_in_queue,
+ freed);
+ priv->stations[sta_id].tid[tid].tfds_in_queue = 0;
+ }
+}
+EXPORT_SYMBOL(iwl_free_tfds_in_queue);
+
/**
* iwl_tx_queue_free - Deallocate DMA queue.
* @txq: Transmit queue to deallocate.
@@ -1559,7 +1573,7 @@
if (txq->q.read_ptr != (ba_resp_scd_ssn & 0xff)) {
/* calculate mac80211 ampdu sw queue to wake */
int freed = iwl_tx_queue_reclaim(priv, scd_flow, index);
- priv->stations[sta_id].tid[tid].tfds_in_queue -= freed;
+ iwl_free_tfds_in_queue(priv, sta_id, tid, freed);
if ((iwl_queue_space(&txq->q) > txq->q.low_mark) &&
priv->mac80211_registered &&