--- /dev/null
+/*
+ * Copyright (C) 2018 Felix Fietkau <nbd@nbd.name>
+ *
+ * Permission to use, copy, modify, and/or distribute this software for any
+ * purpose with or without fee is hereby granted, provided that the above
+ * copyright notice and this permission notice appear in all copies.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
+ * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
+ * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
+ * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
+ * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
+ * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
+ * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
+ */
+#include "mt76.h"
+
+#define REORDER_TIMEOUT (HZ / 10)
+
+static void
+mt76_aggr_release(struct mt76_rx_tid *tid, struct sk_buff_head *frames, int idx)
+{
+ struct sk_buff *skb;
+
+ tid->head = ieee80211_sn_inc(tid->head);
+
+ skb = tid->reorder_buf[idx];
+ if (!skb)
+ return;
+
+ tid->reorder_buf[idx] = NULL;
+ tid->nframes--;
+ __skb_queue_tail(frames, skb);
+}
+
+static void
+mt76_rx_aggr_release_frames(struct mt76_rx_tid *tid, struct sk_buff_head *frames,
+ u16 head)
+{
+ int idx;
+
+ while (ieee80211_sn_less(tid->head, head)) {
+ idx = tid->head % tid->size;
+ mt76_aggr_release(tid, frames, idx);
+ }
+}
+
+static void
+mt76_rx_aggr_release_head(struct mt76_rx_tid *tid, struct sk_buff_head *frames)
+{
+ int idx = tid->head % tid->size;
+
+ while (tid->reorder_buf[idx]) {
+ mt76_aggr_release(tid, frames, idx);
+ idx = tid->head % tid->size;
+ }
+}
+
+static void
+mt76_rx_aggr_check_release(struct mt76_rx_tid *tid, struct sk_buff_head *frames)
+{
+ struct mt76_rx_status *status;
+ struct sk_buff *skb;
+ int start, idx, nframes;
+
+ if (!tid->nframes)
+ return;
+
+ mt76_rx_aggr_release_head(tid, frames);
+
+ start = tid->head % tid->size;
+ nframes = tid->nframes;
+
+ for (idx = (tid->head + 1) % tid->size;
+ idx != start && nframes;
+ idx = (idx + 1) % tid->size) {
+
+ skb = tid->reorder_buf[idx];
+ if (!skb)
+ continue;
+
+ nframes--;
+ status = (struct mt76_rx_status *) skb->cb;
+ if (!time_after(jiffies, status->reorder_time +
+ REORDER_TIMEOUT))
+ continue;
+
+ mt76_rx_aggr_release_frames(tid, frames, status->seqno);
+ }
+
+ mt76_rx_aggr_release_head(tid, frames);
+}
+
+static void
+mt76_rx_aggr_reorder_work(struct work_struct *work)
+{
+ struct mt76_rx_tid *tid = container_of(work, struct mt76_rx_tid,
+ reorder_work.work);
+ struct mt76_dev *dev = tid->dev;
+ struct ieee80211_sta *sta;
+ struct sk_buff_head frames;
+ struct sk_buff *skb;
+
+ __skb_queue_head_init(&frames);
+
+ local_bh_disable();
+
+ spin_lock(&tid->lock);
+ mt76_rx_aggr_check_release(tid, &frames);
+ spin_unlock(&tid->lock);
+
+ ieee80211_queue_delayed_work(tid->dev->hw, &tid->reorder_work, REORDER_TIMEOUT);
+
+ while ((skb = __skb_dequeue(&frames)) != NULL) {
+ sta = mt76_rx_convert(skb);
+ ieee80211_rx_napi(dev->hw, sta, skb, NULL);
+ }
+
+ local_bh_enable();
+}
+
+void mt76_rx_aggr_reorder(struct sk_buff *skb, struct sk_buff_head *frames)
+{
+ struct mt76_rx_status *status = (struct mt76_rx_status *) skb->cb;
+ struct mt76_wcid *wcid = status->wcid;
+ struct ieee80211_sta *sta;
+ struct mt76_rx_tid *tid;
+ bool sn_less;
+ u16 seqno, head, size;
+ u8 idx;
+
+ __skb_queue_tail(frames, skb);
+
+ sta = wcid_to_sta(wcid);
+ if (!sta || !status->aggr)
+ return;
+
+ tid = rcu_dereference(wcid->aggr[status->tid]);
+ if (!tid)
+ return;
+
+ spin_lock_bh(&tid->lock);
+
+ if (tid->stopped)
+ goto out;
+
+ head = tid->head;
+ seqno = status->seqno;
+ size = tid->size;
+ sn_less = ieee80211_sn_less(seqno, head);
+
+ if (!tid->started) {
+ if (sn_less)
+ goto out;
+
+ tid->started = true;
+ }
+
+ if (sn_less) {
+ __skb_unlink(skb, frames);
+ dev_kfree_skb(skb);
+ goto out;
+ }
+
+ if (seqno == head) {
+ tid->head = ieee80211_sn_inc(head);
+ if (tid->nframes)
+ mt76_rx_aggr_release_head(tid, frames);
+ goto out;
+ }
+
+ __skb_unlink(skb, frames);
+
+ /*
+ * Frame sequence number exceeds buffering window, free up some space
+ * by releasing previous frames
+ */
+ if (!ieee80211_sn_less(seqno, head + size)) {
+ head = ieee80211_sn_inc(ieee80211_sn_sub(seqno, size));
+ mt76_rx_aggr_release_frames(tid, frames, head);
+ }
+
+ idx = seqno % size;
+
+ /* Discard if the current slot is already in use */
+ if (tid->reorder_buf[idx]) {
+ dev_kfree_skb(skb);
+ goto out;
+ }
+
+ status->reorder_time = jiffies;
+ tid->reorder_buf[idx] = skb;
+ tid->nframes++;
+ mt76_rx_aggr_release_head(tid, frames);
+
+ ieee80211_queue_delayed_work(tid->dev->hw, &tid->reorder_work, REORDER_TIMEOUT);
+
+out:
+ spin_unlock_bh(&tid->lock);
+}
+
+int mt76_rx_aggr_start(struct mt76_dev *dev, struct mt76_wcid *wcid, u8 tidno,
+ u16 ssn, u8 size)
+{
+ struct mt76_rx_tid *tid;
+
+ mt76_rx_aggr_stop(dev, wcid, tidno);
+
+ tid = kzalloc(sizeof(*tid) + size * sizeof(tid->reorder_buf[0]),
+ GFP_KERNEL);
+ if (!tid)
+ return -ENOMEM;
+
+ tid->dev = dev;
+ tid->head = ssn;
+ tid->size = size;
+ INIT_DELAYED_WORK(&tid->reorder_work, mt76_rx_aggr_reorder_work);
+ spin_lock_init(&tid->lock);
+
+ rcu_assign_pointer(wcid->aggr[tidno], tid);
+
+ return 0;
+}
+EXPORT_SYMBOL_GPL(mt76_rx_aggr_start);
+
+static void mt76_rx_aggr_shutdown(struct mt76_dev *dev, struct mt76_rx_tid *tid)
+{
+ u8 size = tid->size;
+ int i;
+
+ spin_lock_bh(&tid->lock);
+
+ tid->stopped = true;
+ for (i = 0; tid->nframes && i < size; i++) {
+ struct sk_buff *skb = tid->reorder_buf[i];
+
+ if (!skb)
+ continue;
+
+ tid->nframes--;
+ dev_kfree_skb(skb);
+ }
+
+ spin_unlock_bh(&tid->lock);
+
+ cancel_delayed_work_sync(&tid->reorder_work);
+}
+
+void mt76_rx_aggr_stop(struct mt76_dev *dev, struct mt76_wcid *wcid, u8 tidno)
+{
+ struct mt76_rx_tid *tid;
+
+ rcu_read_lock();
+
+ tid = rcu_dereference(wcid->aggr[tidno]);
+ if (tid) {
+ rcu_assign_pointer(wcid->aggr[tidno], NULL);
+ mt76_rx_aggr_shutdown(dev, tid);
+ kfree_rcu(tid, rcu_head);
+ }
+
+ rcu_read_unlock();
+}
+EXPORT_SYMBOL_GPL(mt76_rx_aggr_stop);
projects / linux-2.6-microblaze.git / commitdiff