b43: Add QOS support

This adds QOS support to the b43 driver.
QOS can be disabled on driver level with a module parameter for debugging purposes.

Signed-off-by: Michael Buesch <mb@bu3sch.de>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

1 files changed, 40 insertions, 50 deletions

diff --git a/drivers/net/wireless/b43/dma.c b/drivers/net/wireless/b43/dma.c
index 3dfb28a34be9..c8ead465497a 100644
--- a/drivers/net/wireless/b43/dma.c
+++ b/drivers/net/wireless/b43/dma.c
@@ -291,52 +291,6 @@ static inline int request_slot(struct b43_dmaring *ring)
         return slot;
 }
 
-/* Mac80211-queue to b43-ring mapping */
-static struct b43_dmaring *priority_to_txring(struct b43_wldev *dev,
-                                              int queue_priority)
-{
-        struct b43_dmaring *ring;
-
-/*FIXME: For now we always run on TX-ring-1 */
-        return dev->dma.tx_ring1;
-
-        /* 0 = highest priority */
-        switch (queue_priority) {
-        default:
-                B43_WARN_ON(1);
-                /* fallthrough */
-        case 0:
-                ring = dev->dma.tx_ring3;
-                break;
-        case 1:
-                ring = dev->dma.tx_ring2;
-                break;
-        case 2:
-                ring = dev->dma.tx_ring1;
-                break;
-        case 3:
-                ring = dev->dma.tx_ring0;
-                break;
-        }
-
-        return ring;
-}
-
-/* b43-ring to mac80211-queue mapping */
-static inline int txring_to_priority(struct b43_dmaring *ring)
-{
-        static const u8 idx_to_prio[] = { 3, 2, 1, 0, };
-        unsigned int index;
-
-/*FIXME: have only one queue, for now */
-        return 0;
-
-        index = ring->index;
-        if (B43_WARN_ON(index >= ARRAY_SIZE(idx_to_prio)))
-                index = 0;
-        return idx_to_prio[index];
-}
-
 static u16 b43_dmacontroller_base(enum b43_dmatype type, int controller_idx)
 {
         static const u16 map64[] = {
@@ -1272,6 +1226,37 @@ static inline int should_inject_overflow(struct b43_dmaring *ring)
         return 0;
 }
 
+/* Static mapping of mac80211's queues (priorities) to b43 DMA rings. */
+static struct b43_dmaring * select_ring_by_priority(struct b43_wldev *dev,
+                                                    u8 queue_prio)
+{
+        struct b43_dmaring *ring;
+
+        if (b43_modparam_qos) {
+                /* 0 = highest priority */
+                switch (queue_prio) {
+                default:
+                        B43_WARN_ON(1);
+                        /* fallthrough */
+                case 0:
+                        ring = dev->dma.tx_ring3; /* AC_VO */
+                        break;
+                case 1:
+                        ring = dev->dma.tx_ring2; /* AC_VI */
+                        break;
+                case 2:
+                        ring = dev->dma.tx_ring1; /* AC_BE */
+                        break;
+                case 3:
+                        ring = dev->dma.tx_ring0; /* AC_BK */
+                        break;
+                }
+        } else
+                ring = dev->dma.tx_ring1;
+
+        return ring;
+}
+
 int b43_dma_tx(struct b43_wldev *dev,
                struct sk_buff *skb, struct ieee80211_tx_control *ctl)
 {
@@ -1294,7 +1279,7 @@ int b43_dma_tx(struct b43_wldev *dev,
                 hdr->frame_control |= cpu_to_le16(IEEE80211_FCTL_MOREDATA);
         } else {
                 /* Decide by priority where to put this frame. */
-                ring = priority_to_txring(dev, ctl->queue);
+                ring = select_ring_by_priority(dev, ctl->queue);
         }
 
         spin_lock_irqsave(&ring->lock, flags);
@@ -1309,6 +1294,11 @@ int b43_dma_tx(struct b43_wldev *dev,
          * That would be a mac80211 bug. */
         B43_WARN_ON(ring->stopped);
 
+        /* Assign the queue number to the ring (if not already done before)
+         * so TX status handling can use it. The queue to ring mapping is
+         * static, so we don't need to store it per frame. */
+        ring->queue_prio = ctl->queue;
+
         err = dma_tx_fragment(ring, skb, ctl);
         if (unlikely(err == -ENOKEY)) {
                 /* Drop this packet, as we don't have the encryption key
@@ -1325,7 +1315,7 @@ int b43_dma_tx(struct b43_wldev *dev,
         if ((free_slots(ring) < SLOTS_PER_PACKET) ||
             should_inject_overflow(ring)) {
                 /* This TX ring is full. */
-                ieee80211_stop_queue(dev->wl->hw, txring_to_priority(ring));
+                ieee80211_stop_queue(dev->wl->hw, ctl->queue);
                 ring->stopped = 1;
                 if (b43_debug(dev, B43_DBG_DMAVERBOSE)) {
                         b43dbg(dev->wl, "Stopped TX ring %d\n", ring->index);
@@ -1404,7 +1394,7 @@ void b43_dma_handle_txstatus(struct b43_wldev *dev,
         dev->stats.last_tx = jiffies;
         if (ring->stopped) {
                 B43_WARN_ON(free_slots(ring) < SLOTS_PER_PACKET);
-                ieee80211_wake_queue(dev->wl->hw, txring_to_priority(ring));
+                ieee80211_wake_queue(dev->wl->hw, ring->queue_prio);
                 ring->stopped = 0;
                 if (b43_debug(dev, B43_DBG_DMAVERBOSE)) {
                         b43dbg(dev->wl, "Woke up TX ring %d\n", ring->index);
@@ -1425,7 +1415,7 @@ void b43_dma_get_tx_stats(struct b43_wldev *dev,
 
         for (i = 0; i < nr_queues; i++) {
                 data = &(stats->data[i]);
-                ring = priority_to_txring(dev, i);
+                ring = select_ring_by_priority(dev, i);
 
                 spin_lock_irqsave(&ring->lock, flags);
                 data->len = ring->used_slots / SLOTS_PER_PACKET;