-/* Process received BAR frame */
-
-static int ath_bar_rx(struct ath_softc *sc,
- struct ath_node *an,
- struct sk_buff *skb)
-{
- struct ieee80211_bar *bar;
- struct ath_arx_tid *rxtid;
- struct sk_buff *tskb;
- struct ath_recv_status *rx_status;
- int tidno, index, cindex;
- u16 seqno;
-
- /* look at BAR contents */
-
- bar = (struct ieee80211_bar *)skb->data;
- tidno = (le16_to_cpu(bar->control) & IEEE80211_BAR_CTL_TID_M)
- >> IEEE80211_BAR_CTL_TID_S;
- seqno = le16_to_cpu(bar->start_seq_num) >> IEEE80211_SEQ_SEQ_SHIFT;
-
- /* process BAR - indicate all pending RX frames till the BAR seqno */
-
- rxtid = &an->an_aggr.rx.tid[tidno];
-
- spin_lock_bh(&rxtid->tidlock);
-
- /* get relative index */
-
- index = ATH_BA_INDEX(rxtid->seq_next, seqno);
-
- /* drop BAR if old sequence (index is too large) */
-
- if ((index > rxtid->baw_size) &&
- (index > (IEEE80211_SEQ_MAX - (rxtid->baw_size << 2))))
- /* discard frame, ieee layer may not treat frame as a dup */
- goto unlock_and_free;
-
- /* complete receive processing for all pending frames upto BAR seqno */
-
- cindex = (rxtid->baw_head + index) & (ATH_TID_MAX_BUFS - 1);
- while ((rxtid->baw_head != rxtid->baw_tail) &&
- (rxtid->baw_head != cindex)) {
- tskb = rxtid->rxbuf[rxtid->baw_head].rx_wbuf;
- rx_status = &rxtid->rxbuf[rxtid->baw_head].rx_status;
- rxtid->rxbuf[rxtid->baw_head].rx_wbuf = NULL;
-
- if (tskb != NULL)
- ath_rx_subframe(an, tskb, rx_status);
-
- INCR(rxtid->baw_head, ATH_TID_MAX_BUFS);
- INCR(rxtid->seq_next, IEEE80211_SEQ_MAX);
- }
-
- /* ... and indicate rest of the frames in-order */
-
- while (rxtid->baw_head != rxtid->baw_tail &&
- rxtid->rxbuf[rxtid->baw_head].rx_wbuf != NULL) {
- tskb = rxtid->rxbuf[rxtid->baw_head].rx_wbuf;
- rx_status = &rxtid->rxbuf[rxtid->baw_head].rx_status;
- rxtid->rxbuf[rxtid->baw_head].rx_wbuf = NULL;
-
- ath_rx_subframe(an, tskb, rx_status);
-
- INCR(rxtid->baw_head, ATH_TID_MAX_BUFS);
- INCR(rxtid->seq_next, IEEE80211_SEQ_MAX);
- }
-
-unlock_and_free:
- spin_unlock_bh(&rxtid->tidlock);
- /* free bar itself */
- dev_kfree_skb(skb);
- return IEEE80211_FTYPE_CTL;
-}
-
-/* Function to handle a subframe of aggregation when HT is enabled */
-
-static int ath_ampdu_input(struct ath_softc *sc,
- struct ath_node *an,
- struct sk_buff *skb,
- struct ath_recv_status *rx_status)
-{
- struct ieee80211_hdr *hdr;
- struct ath_arx_tid *rxtid;
- struct ath_rxbuf *rxbuf;
- u8 type, subtype;
- u16 rxseq;
- int tid = 0, index, cindex, rxdiff;
- __le16 fc;
- u8 *qc;
-
- hdr = (struct ieee80211_hdr *)skb->data;
- fc = hdr->frame_control;
-
- /* collect stats of frames with non-zero version */
-
- if ((le16_to_cpu(hdr->frame_control) & IEEE80211_FCTL_VERS) != 0) {
- dev_kfree_skb(skb);
- return -1;
- }
-
- type = le16_to_cpu(hdr->frame_control) & IEEE80211_FCTL_FTYPE;
- subtype = le16_to_cpu(hdr->frame_control) & IEEE80211_FCTL_STYPE;
-
- if (ieee80211_is_back_req(fc))
- return ath_bar_rx(sc, an, skb);
-
- /* special aggregate processing only for qos unicast data frames */
-
- if (!ieee80211_is_data(fc) ||
- !ieee80211_is_data_qos(fc) ||
- is_multicast_ether_addr(hdr->addr1))
- return ath_rx_subframe(an, skb, rx_status);
-
- /* lookup rx tid state */
-
- if (ieee80211_is_data_qos(fc)) {
- qc = ieee80211_get_qos_ctl(hdr);
- tid = qc[0] & 0xf;
- }
-
- if (sc->sc_ah->ah_opmode == ATH9K_M_STA) {
- /* Drop the frame not belonging to me. */
- if (memcmp(hdr->addr1, sc->sc_myaddr, ETH_ALEN)) {
- dev_kfree_skb(skb);
- return -1;
- }
- }
-
- rxtid = &an->an_aggr.rx.tid[tid];
-
- spin_lock(&rxtid->tidlock);
-
- rxdiff = (rxtid->baw_tail - rxtid->baw_head) &
- (ATH_TID_MAX_BUFS - 1);
-
- /*
- * If the ADDBA exchange has not been completed by the source,
- * process via legacy path (i.e. no reordering buffer is needed)
- */
- if (!rxtid->addba_exchangecomplete) {
- spin_unlock(&rxtid->tidlock);
- return ath_rx_subframe(an, skb, rx_status);
- }
-
- /* extract sequence number from recvd frame */
-
- rxseq = le16_to_cpu(hdr->seq_ctrl) >> IEEE80211_SEQ_SEQ_SHIFT;
-
- if (rxtid->seq_reset) {
- rxtid->seq_reset = 0;
- rxtid->seq_next = rxseq;
- }
-
- index = ATH_BA_INDEX(rxtid->seq_next, rxseq);
-
- /* drop frame if old sequence (index is too large) */
-
- if (index > (IEEE80211_SEQ_MAX - (rxtid->baw_size << 2))) {
- /* discard frame, ieee layer may not treat frame as a dup */
- spin_unlock(&rxtid->tidlock);
- dev_kfree_skb(skb);
- return IEEE80211_FTYPE_DATA;
- }
-
- /* sequence number is beyond block-ack window */
-
- if (index >= rxtid->baw_size) {
-
- /* complete receive processing for all pending frames */
-
- while (index >= rxtid->baw_size) {
-
- rxbuf = rxtid->rxbuf + rxtid->baw_head;
-
- if (rxbuf->rx_wbuf != NULL) {
- ath_rx_subframe(an, rxbuf->rx_wbuf,
- &rxbuf->rx_status);
- rxbuf->rx_wbuf = NULL;
- }
-
- INCR(rxtid->baw_head, ATH_TID_MAX_BUFS);
- INCR(rxtid->seq_next, IEEE80211_SEQ_MAX);
-
- index--;
- }
- }
-
- /* add buffer to the recv ba window */
-
- cindex = (rxtid->baw_head + index) & (ATH_TID_MAX_BUFS - 1);
- rxbuf = rxtid->rxbuf + cindex;
-
- if (rxbuf->rx_wbuf != NULL) {
- spin_unlock(&rxtid->tidlock);
- /* duplicate frame */
- dev_kfree_skb(skb);
- return IEEE80211_FTYPE_DATA;
- }
-
- rxbuf->rx_wbuf = skb;
- rxbuf->rx_time = get_timestamp();
- rxbuf->rx_status = *rx_status;
-
- /* advance tail if sequence received is newer
- * than any received so far */
-
- if (index >= rxdiff) {
- rxtid->baw_tail = cindex;
- INCR(rxtid->baw_tail, ATH_TID_MAX_BUFS);
- }
-
- /* indicate all in-order received frames */
-
- while (rxtid->baw_head != rxtid->baw_tail) {
- rxbuf = rxtid->rxbuf + rxtid->baw_head;
- if (!rxbuf->rx_wbuf)
- break;
-
- ath_rx_subframe(an, rxbuf->rx_wbuf, &rxbuf->rx_status);
- rxbuf->rx_wbuf = NULL;
-
- INCR(rxtid->baw_head, ATH_TID_MAX_BUFS);
- INCR(rxtid->seq_next, IEEE80211_SEQ_MAX);
- }
-
- /*
- * start a timer to flush all received frames if there are pending
- * receive frames
- */
- if (rxtid->baw_head != rxtid->baw_tail)
- mod_timer(&rxtid->timer, ATH_RX_TIMEOUT);
- else
- del_timer_sync(&rxtid->timer);
-
- spin_unlock(&rxtid->tidlock);
- return IEEE80211_FTYPE_DATA;
-}
-
-/* Timer to flush all received sub-frames */
-
-static void ath_rx_timer(unsigned long data)
-{
- struct ath_arx_tid *rxtid = (struct ath_arx_tid *)data;
- struct ath_node *an = rxtid->an;
- struct ath_rxbuf *rxbuf;
- int nosched;
-
- spin_lock_bh(&rxtid->tidlock);
- while (rxtid->baw_head != rxtid->baw_tail) {
- rxbuf = rxtid->rxbuf + rxtid->baw_head;
- if (!rxbuf->rx_wbuf) {
- INCR(rxtid->baw_head, ATH_TID_MAX_BUFS);
- INCR(rxtid->seq_next, IEEE80211_SEQ_MAX);
- continue;
- }
-
- /*
- * Stop if the next one is a very recent frame.
- *
- * Call get_timestamp in every iteration to protect against the
- * case in which a new frame is received while we are executing
- * this function. Using a timestamp obtained before entering
- * the loop could lead to a very large time interval
- * (a negative value typecast to unsigned), breaking the
- * function's logic.
- */
- if ((get_timestamp() - rxbuf->rx_time) <
- (ATH_RX_TIMEOUT * HZ / 1000))
- break;
-
- ath_rx_subframe(an, rxbuf->rx_wbuf,
- &rxbuf->rx_status);
- rxbuf->rx_wbuf = NULL;
-
- INCR(rxtid->baw_head, ATH_TID_MAX_BUFS);
- INCR(rxtid->seq_next, IEEE80211_SEQ_MAX);
- }
-
- /*
- * start a timer to flush all received frames if there are pending
- * receive frames
- */
- if (rxtid->baw_head != rxtid->baw_tail)
- nosched = 0;
- else
- nosched = 1; /* no need to re-arm the timer again */
-
- spin_unlock_bh(&rxtid->tidlock);
-}
-
-/* Free all pending sub-frames in the re-ordering buffer */
-
-static void ath_rx_flush_tid(struct ath_softc *sc, struct ath_arx_tid *rxtid,
- int drop)
-{
- struct ath_rxbuf *rxbuf;
- unsigned long flag;
-
- spin_lock_irqsave(&rxtid->tidlock, flag);
- while (rxtid->baw_head != rxtid->baw_tail) {
- rxbuf = rxtid->rxbuf + rxtid->baw_head;
- if (!rxbuf->rx_wbuf) {
- INCR(rxtid->baw_head, ATH_TID_MAX_BUFS);
- INCR(rxtid->seq_next, IEEE80211_SEQ_MAX);
- continue;
- }
-
- if (drop)
- dev_kfree_skb(rxbuf->rx_wbuf);
- else
- ath_rx_subframe(rxtid->an,
- rxbuf->rx_wbuf,
- &rxbuf->rx_status);
-
- rxbuf->rx_wbuf = NULL;
-
- INCR(rxtid->baw_head, ATH_TID_MAX_BUFS);
- INCR(rxtid->seq_next, IEEE80211_SEQ_MAX);
- }
- spin_unlock_irqrestore(&rxtid->tidlock, flag);
-}
-