mac80211: A-MPDU Tx adding qdisc support

This patch allows qdisc support in A-MPDU Tx. a method to
handle QoS <-> TID switches is present in this patch.

Signed-off-by: Ron Rindjunsky <ron.rindjunsky@intel.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

5 files changed, 155 insertions, 18 deletions

diff --git a/net/mac80211/ieee80211.c b/net/mac80211/ieee80211.c
index c323c9af9b8f..f8e734f0da1a 100644
--- a/net/mac80211/ieee80211.c
+++ b/net/mac80211/ieee80211.c
@@ -462,7 +462,7 @@ int ieee80211_start_tx_ba_session(struct ieee80211_hw *hw, u8 *ra, u16 tid)
         spin_lock_bh(&local->mdev->queue_lock);
 
         /* create a new queue for this aggregation */
-        /* ret = ieee80211_ht_agg_queue_add(local, sta, tid); */
+        ret = ieee80211_ht_agg_queue_add(local, sta, tid);
 
         /* case no queue is available to aggregation
          * don't switch to aggregation */
@@ -488,7 +488,7 @@ int ieee80211_start_tx_ba_session(struct ieee80211_hw *hw, u8 *ra, u16 tid)
                 /* No need to requeue the packets in the agg queue, since we
                  * held the tx lock: no packet could be enqueued to the newly
                  * allocated queue */
-                /* ieee80211_ht_agg_queue_remove(local, sta, tid, 0); */
+                 ieee80211_ht_agg_queue_remove(local, sta, tid, 0);
 #ifdef CONFIG_MAC80211_HT_DEBUG
                 printk(KERN_DEBUG "BA request denied - HW or queue unavailable"
                                 " for tid %d\n", tid);
@@ -499,7 +499,7 @@ int ieee80211_start_tx_ba_session(struct ieee80211_hw *hw, u8 *ra, u16 tid)
         }
 
         /* Will put all the packets in the new SW queue */
-        /* ieee80211_requeue(local, ieee802_1d_to_ac[tid]); */
+        ieee80211_requeue(local, ieee802_1d_to_ac[tid]);
         spin_unlock_bh(&local->mdev->queue_lock);
 
         /* We have most probably almost emptied the legacy queue */
@@ -675,7 +675,7 @@ void ieee80211_stop_tx_ba_cb(struct ieee80211_hw *hw, u8 *ra, u8 tid)
          * the content of the qdiscs */
         spin_lock_bh(&local->mdev->queue_lock);
         /* remove the queue for this aggregation */
-        /* ieee80211_ht_agg_queue_remove(local, sta, tid, 1); */
+        ieee80211_ht_agg_queue_remove(local, sta, tid, 1);
         spin_unlock_bh(&local->mdev->queue_lock);
 
         /* we just requeued the all the frames that were in the removed
diff --git a/net/mac80211/ieee80211_i.h b/net/mac80211/ieee80211_i.h
index 8a24c2c6ebc1..cfd0717c0033 100644
--- a/net/mac80211/ieee80211_i.h
+++ b/net/mac80211/ieee80211_i.h
@@ -165,6 +165,7 @@ struct ieee80211_txrx_data {
 #define IEEE80211_TXPD_DO_NOT_ENCRYPT   BIT(1)
 #define IEEE80211_TXPD_REQUEUE          BIT(2)
 #define IEEE80211_TXPD_EAPOL_FRAME      BIT(3)
+#define IEEE80211_TXPD_AMPDU            BIT(4)
 /* Stored in sk_buff->cb */
 struct ieee80211_tx_packet_data {
         int ifindex;
@@ -452,8 +453,8 @@ struct ieee80211_local {
         struct sta_info *sta_hash[STA_HASH_SIZE];
         struct timer_list sta_cleanup;
 
-        unsigned long state[NUM_TX_DATA_QUEUES];
-        struct ieee80211_tx_stored_packet pending_packet[NUM_TX_DATA_QUEUES];
+        unsigned long state[NUM_TX_DATA_QUEUES_AMPDU];
+        struct ieee80211_tx_stored_packet pending_packet[NUM_TX_DATA_QUEUES_AMPDU];
         struct tasklet_struct tx_pending_tasklet;
 
         /* number of interfaces with corresponding IFF_ flags */
diff --git a/net/mac80211/tx.c b/net/mac80211/tx.c
index 85d01646abf5..38e1b2bd8245 100644
--- a/net/mac80211/tx.c
+++ b/net/mac80211/tx.c
@@ -1260,6 +1260,8 @@ int ieee80211_master_start_xmit(struct sk_buff *skb,
                 control.flags |= IEEE80211_TXCTL_REQUEUE;
         if (pkt_data->flags & IEEE80211_TXPD_EAPOL_FRAME)
                 control.flags |= IEEE80211_TXCTL_EAPOL_FRAME;
+        if (pkt_data->flags & IEEE80211_TXPD_AMPDU)
+                control.flags |= IEEE80211_TXCTL_AMPDU;
         control.queue = pkt_data->queue;
 
         ret = ieee80211_tx(odev, skb, &control);
diff --git a/net/mac80211/wme.c b/net/mac80211/wme.c
index 4e236599dd31..425aa8588ea0 100644
--- a/net/mac80211/wme.c
+++ b/net/mac80211/wme.c
@@ -19,10 +19,13 @@
 #include "wme.h"
 
 /* maximum number of hardware queues we support. */
-#define TC_80211_MAX_QUEUES 8
+#define TC_80211_MAX_QUEUES 16
+
+const int ieee802_1d_to_ac[8] = { 2, 3, 3, 2, 1, 1, 0, 0 };
 
 struct ieee80211_sched_data
 {
+        unsigned long qdisc_pool;
         struct tcf_proto *filter_list;
         struct Qdisc *queues[TC_80211_MAX_QUEUES];
         struct sk_buff_head requeued[TC_80211_MAX_QUEUES];
@@ -98,7 +101,6 @@ static inline int classify80211(struct sk_buff *skb, struct Qdisc *qd)
         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
         unsigned short fc = le16_to_cpu(hdr->frame_control);
         int qos;
-        const int ieee802_1d_to_ac[8] = { 2, 3, 3, 2, 1, 1, 0, 0 };
 
         /* see if frame is data or non data frame */
         if (unlikely((fc & IEEE80211_FCTL_FTYPE) != IEEE80211_FTYPE_DATA)) {
@@ -146,9 +148,25 @@ static int wme_qdiscop_enqueue(struct sk_buff *skb, struct Qdisc* qd)
         unsigned short fc = le16_to_cpu(hdr->frame_control);
         struct Qdisc *qdisc;
         int err, queue;
+        struct sta_info *sta;
+        u8 tid;
 
         if (pkt_data->flags & IEEE80211_TXPD_REQUEUE) {
-                skb_queue_tail(&q->requeued[pkt_data->queue], skb);
+                queue = pkt_data->queue;
+                sta = sta_info_get(local, hdr->addr1);
+                tid = skb->priority & QOS_CONTROL_TAG1D_MASK;
+                if (sta) {
+                        int ampdu_queue = sta->tid_to_tx_q[tid];
+                        if ((ampdu_queue < local->hw.queues) &&
+                            test_bit(ampdu_queue, &q->qdisc_pool)) {
+                                queue = ampdu_queue;
+                                pkt_data->flags |= IEEE80211_TXPD_AMPDU;
+                        } else {
+                                pkt_data->flags &= ~IEEE80211_TXPD_AMPDU;
+                        }
+                        sta_info_put(sta);
+                }
+                skb_queue_tail(&q->requeued[queue], skb);
                 qd->q.qlen++;
                 return 0;
         }
@@ -159,14 +177,28 @@ static int wme_qdiscop_enqueue(struct sk_buff *skb, struct Qdisc* qd)
          */
         if (WLAN_FC_IS_QOS_DATA(fc)) {
                 u8 *p = skb->data + ieee80211_get_hdrlen(fc) - 2;
-                u8 qos_hdr = skb->priority & QOS_CONTROL_TAG1D_MASK;
+                u8 ack_policy = 0;
+                tid = skb->priority & QOS_CONTROL_TAG1D_MASK;
                 if (local->wifi_wme_noack_test)
-                        qos_hdr |= QOS_CONTROL_ACK_POLICY_NOACK <<
+                        ack_policy |= QOS_CONTROL_ACK_POLICY_NOACK <<
                                         QOS_CONTROL_ACK_POLICY_SHIFT;
                 /* qos header is 2 bytes, second reserved */
-                *p = qos_hdr;
+                *p = ack_policy | tid;
                 p++;
                 *p = 0;
+
+                sta = sta_info_get(local, hdr->addr1);
+                if (sta) {
+                        int ampdu_queue = sta->tid_to_tx_q[tid];
+                        if ((ampdu_queue < local->hw.queues) &&
+                                test_bit(ampdu_queue, &q->qdisc_pool)) {
+                                queue = ampdu_queue;
+                                pkt_data->flags |= IEEE80211_TXPD_AMPDU;
+                        } else {
+                                pkt_data->flags &= ~IEEE80211_TXPD_AMPDU;
+                        }
+                        sta_info_put(sta);
+                }
         }
 
         if (unlikely(queue >= local->hw.queues)) {
@@ -184,6 +216,7 @@ static int wme_qdiscop_enqueue(struct sk_buff *skb, struct Qdisc* qd)
                         kfree_skb(skb);
                         err = NET_XMIT_DROP;
         } else {
+                tid = skb->priority & QOS_CONTROL_TAG1D_MASK;
                 pkt_data->queue = (unsigned int) queue;
                 qdisc = q->queues[queue];
                 err = qdisc->enqueue(skb, qdisc);
@@ -235,10 +268,11 @@ static struct sk_buff *wme_qdiscop_dequeue(struct Qdisc* qd)
         /* check all the h/w queues in numeric/priority order */
         for (queue = 0; queue < hw->queues; queue++) {
                 /* see if there is room in this hardware queue */
-                if (test_bit(IEEE80211_LINK_STATE_XOFF,
-                             &local->state[queue]) ||
-                    test_bit(IEEE80211_LINK_STATE_PENDING,
-                             &local->state[queue]))
+                if ((test_bit(IEEE80211_LINK_STATE_XOFF,
+                                &local->state[queue])) ||
+                    (test_bit(IEEE80211_LINK_STATE_PENDING,
+                                &local->state[queue])) ||
+                         (!test_bit(queue, &q->qdisc_pool)))
                         continue;
 
                 /* there is space - try and get a frame */
@@ -360,6 +394,10 @@ static int wme_qdiscop_init(struct Qdisc *qd, struct nlattr *opt)
                 }
         }
 
+        /* reserve all legacy QoS queues */
+        for (i = 0; i < min(IEEE80211_TX_QUEUE_DATA4, queues); i++)
+                set_bit(i, &q->qdisc_pool);
+
         return err;
 }
 
@@ -605,3 +643,80 @@ void ieee80211_wme_unregister(void)
 {
         unregister_qdisc(&wme_qdisc_ops);
 }
+
+int ieee80211_ht_agg_queue_add(struct ieee80211_local *local,
+                        struct sta_info *sta, u16 tid)
+{
+        int i;
+        struct ieee80211_sched_data *q =
+                        qdisc_priv(local->mdev->qdisc_sleeping);
+        DECLARE_MAC_BUF(mac);
+
+        /* prepare the filter and save it for the SW queue
+         * matching the recieved HW queue */
+
+        /* try to get a Qdisc from the pool */
+        for (i = IEEE80211_TX_QUEUE_BEACON; i < local->hw.queues; i++)
+                if (!test_and_set_bit(i, &q->qdisc_pool)) {
+                        ieee80211_stop_queue(local_to_hw(local), i);
+                        sta->tid_to_tx_q[tid] = i;
+
+                        /* IF there are already pending packets
+                         * on this tid first we need to drain them
+                         * on the previous queue
+                         * since HT is strict in order */
+#ifdef CONFIG_MAC80211_HT_DEBUG
+                        if (net_ratelimit())
+                                printk(KERN_DEBUG "allocated aggregation queue"
+                                        " %d tid %d addr %s pool=0x%lX\n",
+                                        i, tid, print_mac(mac, sta->addr),
+                                        q->qdisc_pool);
+#endif /* CONFIG_MAC80211_HT_DEBUG */
+                        return 0;
+                }
+
+        return -EAGAIN;
+}
+
+/**
+ * the caller needs to hold local->mdev->queue_lock
+ */
+void ieee80211_ht_agg_queue_remove(struct ieee80211_local *local,
+                                   struct sta_info *sta, u16 tid,
+                                   u8 requeue)
+{
+        struct ieee80211_sched_data *q =
+                qdisc_priv(local->mdev->qdisc_sleeping);
+        int agg_queue = sta->tid_to_tx_q[tid];
+
+        /* return the qdisc to the pool */
+        clear_bit(agg_queue, &q->qdisc_pool);
+        sta->tid_to_tx_q[tid] = local->hw.queues;
+
+        if (requeue)
+                ieee80211_requeue(local, agg_queue);
+        else
+                q->queues[agg_queue]->ops->reset(q->queues[agg_queue]);
+}
+
+void ieee80211_requeue(struct ieee80211_local *local, int queue)
+{
+        struct Qdisc *root_qd = local->mdev->qdisc_sleeping;
+        struct ieee80211_sched_data *q = qdisc_priv(root_qd);
+        struct Qdisc *qdisc = q->queues[queue];
+        struct sk_buff *skb = NULL;
+        u32 len = qdisc->q.qlen;
+
+        if (!qdisc || !qdisc->dequeue)
+                return;
+
+        printk(KERN_DEBUG "requeue: qlen = %d\n", qdisc->q.qlen);
+        for (len = qdisc->q.qlen; len > 0; len--) {
+                skb = qdisc->dequeue(qdisc);
+                root_qd->q.qlen--;
+                /* packet will be classified again and */
+                /* skb->packet_data->queue will be overridden if needed */
+                if (skb)
+                        wme_qdiscop_enqueue(skb, root_qd);
+        }
+}
diff --git a/net/mac80211/wme.h b/net/mac80211/wme.h
index 76c713a6450c..fcc6b05508cc 100644
--- a/net/mac80211/wme.h
+++ b/net/mac80211/wme.h
@@ -24,6 +24,8 @@
 
 #define QOS_CONTROL_TAG1D_MASK 0x07
 
+extern const int ieee802_1d_to_ac[8];
+
 static inline int WLAN_FC_IS_QOS_DATA(u16 fc)
 {
         return (fc & 0x8C) == 0x88;
@@ -32,7 +34,12 @@ static inline int WLAN_FC_IS_QOS_DATA(u16 fc)
 #ifdef CONFIG_NET_SCHED
 void ieee80211_install_qdisc(struct net_device *dev);
 int ieee80211_qdisc_installed(struct net_device *dev);
-
+int ieee80211_ht_agg_queue_add(struct ieee80211_local *local,
+                               struct sta_info *sta, u16 tid);
+void ieee80211_ht_agg_queue_remove(struct ieee80211_local *local,
+                                   struct sta_info *sta, u16 tid,
+                                   u8 requeue);
+void ieee80211_requeue(struct ieee80211_local *local, int queue);
 int ieee80211_wme_register(void);
 void ieee80211_wme_unregister(void);
 #else
@@ -43,7 +50,19 @@ static inline int ieee80211_qdisc_installed(struct net_device *dev)
 {
         return 0;
 }
-
+static inline int ieee80211_ht_agg_queue_add(struct ieee80211_local *local,
+                                             struct sta_info *sta, u16 tid)
+{
+        return -EAGAIN;
+}
+static inline void ieee80211_ht_agg_queue_remove(struct ieee80211_local *local,
+                                                 struct sta_info *sta, u16 tid,
+                                                 u8 requeue)
+{
+}
+static inline void ieee80211_requeue(struct ieee80211_local *local, int queue)
+{
+}
 static inline int ieee80211_wme_register(void)
 {
         return 0;