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;