rt2x00: Queue handling overhaul

This introduces a big queue handling overhaul, this also
renames "ring" to "queues".

Move queue handling into rt2x00queue.c and the matching header,
use Kerneldoc to improve rt2x00 library documentation.

Access to the queues is now protected under a spinlock, this
to prevent race conditions which could corrupt the indexing
system of the queue.

Each queue entry allocates x bytes for driver/device specific data,
this cleans up the queue structure significantly and improves
code readability.

rt2500usb no longer needs 2 entries in the beacon queue to correctly
send out the guardian byte. This is now handled in the entry specific
structure.

rt61 and rt73 now use the correct descriptor size for beacon frames,
since this data is written into the registers not the entire TXD
descriptor was used but instead of a subset of it named TXINFO.

Finally this also fixes numerous other bugs related to incorrect
beacon handling or beacon related code.

Signed-off-by: Ivo van Doorn <IvDoorn@gmail.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
diff --git a/drivers/net/wireless/rt2x00/rt2400pci.c b/drivers/net/wireless/rt2x00/rt2400pci.c
index 763af7f..fc16108 100644
--- a/drivers/net/wireless/rt2x00/rt2400pci.c
+++ b/drivers/net/wireless/rt2x00/rt2400pci.c
@@ -498,13 +498,13 @@
 }
 
 static void rt2400pci_config_cw(struct rt2x00_dev *rt2x00dev,
-				struct ieee80211_tx_queue_params *params)
+				const int cw_min, const int cw_max)
 {
 	u32 reg;
 
 	rt2x00pci_register_read(rt2x00dev, CSR11, &reg);
-	rt2x00_set_field32(&reg, CSR11_CWMIN, params->cw_min);
-	rt2x00_set_field32(&reg, CSR11_CWMAX, params->cw_max);
+	rt2x00_set_field32(&reg, CSR11_CWMIN, cw_min);
+	rt2x00_set_field32(&reg, CSR11_CWMAX, cw_max);
 	rt2x00pci_register_write(rt2x00dev, CSR11, reg);
 }
 
@@ -593,90 +593,89 @@
  * Initialization functions.
  */
 static void rt2400pci_init_rxentry(struct rt2x00_dev *rt2x00dev,
-				   struct data_entry *entry)
+				   struct queue_entry *entry)
 {
-	__le32 *rxd = entry->priv;
+	struct queue_entry_priv_pci_rx *priv_rx = entry->priv_data;
 	u32 word;
 
-	rt2x00_desc_read(rxd, 2, &word);
-	rt2x00_set_field32(&word, RXD_W2_BUFFER_LENGTH, entry->ring->data_size);
-	rt2x00_desc_write(rxd, 2, word);
+	rt2x00_desc_read(priv_rx->desc, 2, &word);
+	rt2x00_set_field32(&word, RXD_W2_BUFFER_LENGTH, entry->queue->data_size);
+	rt2x00_desc_write(priv_rx->desc, 2, word);
 
-	rt2x00_desc_read(rxd, 1, &word);
-	rt2x00_set_field32(&word, RXD_W1_BUFFER_ADDRESS, entry->data_dma);
-	rt2x00_desc_write(rxd, 1, word);
+	rt2x00_desc_read(priv_rx->desc, 1, &word);
+	rt2x00_set_field32(&word, RXD_W1_BUFFER_ADDRESS, priv_rx->dma);
+	rt2x00_desc_write(priv_rx->desc, 1, word);
 
-	rt2x00_desc_read(rxd, 0, &word);
+	rt2x00_desc_read(priv_rx->desc, 0, &word);
 	rt2x00_set_field32(&word, RXD_W0_OWNER_NIC, 1);
-	rt2x00_desc_write(rxd, 0, word);
+	rt2x00_desc_write(priv_rx->desc, 0, word);
 }
 
 static void rt2400pci_init_txentry(struct rt2x00_dev *rt2x00dev,
-				   struct data_entry *entry)
+				   struct queue_entry *entry)
 {
-	__le32 *txd = entry->priv;
+	struct queue_entry_priv_pci_tx *priv_tx = entry->priv_data;
 	u32 word;
 
-	rt2x00_desc_read(txd, 1, &word);
-	rt2x00_set_field32(&word, TXD_W1_BUFFER_ADDRESS, entry->data_dma);
-	rt2x00_desc_write(txd, 1, word);
+	rt2x00_desc_read(priv_tx->desc, 1, &word);
+	rt2x00_set_field32(&word, TXD_W1_BUFFER_ADDRESS, priv_tx->dma);
+	rt2x00_desc_write(priv_tx->desc, 1, word);
 
-	rt2x00_desc_read(txd, 2, &word);
-	rt2x00_set_field32(&word, TXD_W2_BUFFER_LENGTH, entry->ring->data_size);
-	rt2x00_desc_write(txd, 2, word);
+	rt2x00_desc_read(priv_tx->desc, 2, &word);
+	rt2x00_set_field32(&word, TXD_W2_BUFFER_LENGTH,
+			   entry->queue->data_size);
+	rt2x00_desc_write(priv_tx->desc, 2, word);
 
-	rt2x00_desc_read(txd, 0, &word);
+	rt2x00_desc_read(priv_tx->desc, 0, &word);
 	rt2x00_set_field32(&word, TXD_W0_VALID, 0);
 	rt2x00_set_field32(&word, TXD_W0_OWNER_NIC, 0);
-	rt2x00_desc_write(txd, 0, word);
+	rt2x00_desc_write(priv_tx->desc, 0, word);
 }
 
-static int rt2400pci_init_rings(struct rt2x00_dev *rt2x00dev)
+static int rt2400pci_init_queues(struct rt2x00_dev *rt2x00dev)
 {
+	struct queue_entry_priv_pci_rx *priv_rx;
+	struct queue_entry_priv_pci_tx *priv_tx;
 	u32 reg;
 
 	/*
 	 * Initialize registers.
 	 */
 	rt2x00pci_register_read(rt2x00dev, TXCSR2, &reg);
-	rt2x00_set_field32(&reg, TXCSR2_TXD_SIZE,
-			   rt2x00dev->tx[IEEE80211_TX_QUEUE_DATA0].desc_size);
-	rt2x00_set_field32(&reg, TXCSR2_NUM_TXD,
-			   rt2x00dev->tx[IEEE80211_TX_QUEUE_DATA1].stats.limit);
-	rt2x00_set_field32(&reg, TXCSR2_NUM_ATIM,
-			   rt2x00dev->bcn[1].stats.limit);
-	rt2x00_set_field32(&reg, TXCSR2_NUM_PRIO,
-			   rt2x00dev->tx[IEEE80211_TX_QUEUE_DATA0].stats.limit);
+	rt2x00_set_field32(&reg, TXCSR2_TXD_SIZE, rt2x00dev->tx[0].desc_size);
+	rt2x00_set_field32(&reg, TXCSR2_NUM_TXD, rt2x00dev->tx[1].limit);
+	rt2x00_set_field32(&reg, TXCSR2_NUM_ATIM, rt2x00dev->bcn[1].limit);
+	rt2x00_set_field32(&reg, TXCSR2_NUM_PRIO, rt2x00dev->tx[0].limit);
 	rt2x00pci_register_write(rt2x00dev, TXCSR2, reg);
 
+	priv_tx = rt2x00dev->tx[1].entries[0].priv_data;
 	rt2x00pci_register_read(rt2x00dev, TXCSR3, &reg);
-	rt2x00_set_field32(&reg, TXCSR3_TX_RING_REGISTER,
-			   rt2x00dev->tx[IEEE80211_TX_QUEUE_DATA1].data_dma);
+	rt2x00_set_field32(&reg, TXCSR3_TX_RING_REGISTER, priv_tx->dma);
 	rt2x00pci_register_write(rt2x00dev, TXCSR3, reg);
 
+	priv_tx = rt2x00dev->tx[0].entries[0].priv_data;
 	rt2x00pci_register_read(rt2x00dev, TXCSR5, &reg);
-	rt2x00_set_field32(&reg, TXCSR5_PRIO_RING_REGISTER,
-			   rt2x00dev->tx[IEEE80211_TX_QUEUE_DATA0].data_dma);
+	rt2x00_set_field32(&reg, TXCSR5_PRIO_RING_REGISTER, priv_tx->dma);
 	rt2x00pci_register_write(rt2x00dev, TXCSR5, reg);
 
+	priv_tx = rt2x00dev->bcn[1].entries[0].priv_data;
 	rt2x00pci_register_read(rt2x00dev, TXCSR4, &reg);
-	rt2x00_set_field32(&reg, TXCSR4_ATIM_RING_REGISTER,
-			   rt2x00dev->bcn[1].data_dma);
+	rt2x00_set_field32(&reg, TXCSR4_ATIM_RING_REGISTER, priv_tx->dma);
 	rt2x00pci_register_write(rt2x00dev, TXCSR4, reg);
 
+	priv_tx = rt2x00dev->bcn[0].entries[0].priv_data;
 	rt2x00pci_register_read(rt2x00dev, TXCSR6, &reg);
-	rt2x00_set_field32(&reg, TXCSR6_BEACON_RING_REGISTER,
-			   rt2x00dev->bcn[0].data_dma);
+	rt2x00_set_field32(&reg, TXCSR6_BEACON_RING_REGISTER, priv_tx->dma);
 	rt2x00pci_register_write(rt2x00dev, TXCSR6, reg);
 
 	rt2x00pci_register_read(rt2x00dev, RXCSR1, &reg);
 	rt2x00_set_field32(&reg, RXCSR1_RXD_SIZE, rt2x00dev->rx->desc_size);
-	rt2x00_set_field32(&reg, RXCSR1_NUM_RXD, rt2x00dev->rx->stats.limit);
+	rt2x00_set_field32(&reg, RXCSR1_NUM_RXD, rt2x00dev->rx->limit);
 	rt2x00pci_register_write(rt2x00dev, RXCSR1, reg);
 
+	priv_rx = rt2x00dev->rx->entries[0].priv_data;
 	rt2x00pci_register_read(rt2x00dev, RXCSR2, &reg);
-	rt2x00_set_field32(&reg, RXCSR2_RX_RING_REGISTER,
-			   rt2x00dev->rx->data_dma);
+	rt2x00_set_field32(&reg, RXCSR2_RX_RING_REGISTER, priv_tx->dma);
 	rt2x00pci_register_write(rt2x00dev, RXCSR2, reg);
 
 	return 0;
@@ -859,7 +858,7 @@
 	/*
 	 * Initialize all registers.
 	 */
-	if (rt2400pci_init_rings(rt2x00dev) ||
+	if (rt2400pci_init_queues(rt2x00dev) ||
 	    rt2400pci_init_registers(rt2x00dev) ||
 	    rt2400pci_init_bbp(rt2x00dev)) {
 		ERROR(rt2x00dev, "Register initialization failed.\n");
@@ -986,10 +985,10 @@
  */
 static void rt2400pci_write_tx_desc(struct rt2x00_dev *rt2x00dev,
 				    struct sk_buff *skb,
-				    struct txdata_entry_desc *desc,
+				    struct txentry_desc *txdesc,
 				    struct ieee80211_tx_control *control)
 {
-	struct skb_desc *skbdesc = get_skb_desc(skb);
+	struct skb_frame_desc *skbdesc = get_skb_frame_desc(skb);
 	__le32 *txd = skbdesc->desc;
 	u32 word;
 
@@ -1001,19 +1000,19 @@
 	rt2x00_desc_write(txd, 2, word);
 
 	rt2x00_desc_read(txd, 3, &word);
-	rt2x00_set_field32(&word, TXD_W3_PLCP_SIGNAL, desc->signal);
+	rt2x00_set_field32(&word, TXD_W3_PLCP_SIGNAL, txdesc->signal);
 	rt2x00_set_field32(&word, TXD_W3_PLCP_SIGNAL_REGNUM, 5);
 	rt2x00_set_field32(&word, TXD_W3_PLCP_SIGNAL_BUSY, 1);
-	rt2x00_set_field32(&word, TXD_W3_PLCP_SERVICE, desc->service);
+	rt2x00_set_field32(&word, TXD_W3_PLCP_SERVICE, txdesc->service);
 	rt2x00_set_field32(&word, TXD_W3_PLCP_SERVICE_REGNUM, 6);
 	rt2x00_set_field32(&word, TXD_W3_PLCP_SERVICE_BUSY, 1);
 	rt2x00_desc_write(txd, 3, word);
 
 	rt2x00_desc_read(txd, 4, &word);
-	rt2x00_set_field32(&word, TXD_W4_PLCP_LENGTH_LOW, desc->length_low);
+	rt2x00_set_field32(&word, TXD_W4_PLCP_LENGTH_LOW, txdesc->length_low);
 	rt2x00_set_field32(&word, TXD_W3_PLCP_LENGTH_LOW_REGNUM, 8);
 	rt2x00_set_field32(&word, TXD_W3_PLCP_LENGTH_LOW_BUSY, 1);
-	rt2x00_set_field32(&word, TXD_W4_PLCP_LENGTH_HIGH, desc->length_high);
+	rt2x00_set_field32(&word, TXD_W4_PLCP_LENGTH_HIGH, txdesc->length_high);
 	rt2x00_set_field32(&word, TXD_W3_PLCP_LENGTH_HIGH_REGNUM, 7);
 	rt2x00_set_field32(&word, TXD_W3_PLCP_LENGTH_HIGH_BUSY, 1);
 	rt2x00_desc_write(txd, 4, word);
@@ -1022,14 +1021,14 @@
 	rt2x00_set_field32(&word, TXD_W0_OWNER_NIC, 1);
 	rt2x00_set_field32(&word, TXD_W0_VALID, 1);
 	rt2x00_set_field32(&word, TXD_W0_MORE_FRAG,
-			   test_bit(ENTRY_TXD_MORE_FRAG, &desc->flags));
+			   test_bit(ENTRY_TXD_MORE_FRAG, &txdesc->flags));
 	rt2x00_set_field32(&word, TXD_W0_ACK,
-			   test_bit(ENTRY_TXD_ACK, &desc->flags));
+			   test_bit(ENTRY_TXD_ACK, &txdesc->flags));
 	rt2x00_set_field32(&word, TXD_W0_TIMESTAMP,
-			   test_bit(ENTRY_TXD_REQ_TIMESTAMP, &desc->flags));
+			   test_bit(ENTRY_TXD_REQ_TIMESTAMP, &txdesc->flags));
 	rt2x00_set_field32(&word, TXD_W0_RTS,
-			   test_bit(ENTRY_TXD_RTS_FRAME, &desc->flags));
-	rt2x00_set_field32(&word, TXD_W0_IFS, desc->ifs);
+			   test_bit(ENTRY_TXD_RTS_FRAME, &txdesc->flags));
+	rt2x00_set_field32(&word, TXD_W0_IFS, txdesc->ifs);
 	rt2x00_set_field32(&word, TXD_W0_RETRY_MODE,
 			   !!(control->flags &
 			      IEEE80211_TXCTL_LONG_RETRY_LIMIT));
@@ -1066,49 +1065,49 @@
 /*
  * RX control handlers
  */
-static void rt2400pci_fill_rxdone(struct data_entry *entry,
-				  struct rxdata_entry_desc *desc)
+static void rt2400pci_fill_rxdone(struct queue_entry *entry,
+				  struct rxdone_entry_desc *rxdesc)
 {
-	__le32 *rxd = entry->priv;
+	struct queue_entry_priv_pci_rx *priv_rx = entry->priv_data;
 	u32 word0;
 	u32 word2;
 
-	rt2x00_desc_read(rxd, 0, &word0);
-	rt2x00_desc_read(rxd, 2, &word2);
+	rt2x00_desc_read(priv_rx->desc, 0, &word0);
+	rt2x00_desc_read(priv_rx->desc, 2, &word2);
 
-	desc->flags = 0;
+	rxdesc->flags = 0;
 	if (rt2x00_get_field32(word0, RXD_W0_CRC_ERROR))
-		desc->flags |= RX_FLAG_FAILED_FCS_CRC;
+		rxdesc->flags |= RX_FLAG_FAILED_FCS_CRC;
 	if (rt2x00_get_field32(word0, RXD_W0_PHYSICAL_ERROR))
-		desc->flags |= RX_FLAG_FAILED_PLCP_CRC;
+		rxdesc->flags |= RX_FLAG_FAILED_PLCP_CRC;
 
 	/*
 	 * Obtain the status about this packet.
 	 */
-	desc->signal = rt2x00_get_field32(word2, RXD_W2_SIGNAL);
-	desc->rssi = rt2x00_get_field32(word2, RXD_W2_RSSI) -
-	    entry->ring->rt2x00dev->rssi_offset;
-	desc->ofdm = 0;
-	desc->size = rt2x00_get_field32(word0, RXD_W0_DATABYTE_COUNT);
-	desc->my_bss = !!rt2x00_get_field32(word0, RXD_W0_MY_BSS);
+	rxdesc->signal = rt2x00_get_field32(word2, RXD_W2_SIGNAL);
+	rxdesc->rssi = rt2x00_get_field32(word2, RXD_W2_RSSI) -
+	    entry->queue->rt2x00dev->rssi_offset;
+	rxdesc->ofdm = 0;
+	rxdesc->size = rt2x00_get_field32(word0, RXD_W0_DATABYTE_COUNT);
+	rxdesc->my_bss = !!rt2x00_get_field32(word0, RXD_W0_MY_BSS);
 }
 
 /*
  * Interrupt functions.
  */
-static void rt2400pci_txdone(struct rt2x00_dev *rt2x00dev, const int queue)
+static void rt2400pci_txdone(struct rt2x00_dev *rt2x00dev,
+			     const enum ieee80211_tx_queue queue_idx)
 {
-	struct data_ring *ring = rt2x00lib_get_ring(rt2x00dev, queue);
-	struct data_entry *entry;
-	__le32 *txd;
+	struct data_queue *queue = rt2x00queue_get_queue(rt2x00dev, queue_idx);
+	struct queue_entry_priv_pci_tx *priv_tx;
+	struct queue_entry *entry;
+	struct txdone_entry_desc txdesc;
 	u32 word;
-	int tx_status;
-	int retry;
 
-	while (!rt2x00_ring_empty(ring)) {
-		entry = rt2x00_get_data_entry_done(ring);
-		txd = entry->priv;
-		rt2x00_desc_read(txd, 0, &word);
+	while (!rt2x00queue_empty(queue)) {
+		entry = rt2x00queue_get_entry(queue, Q_INDEX_DONE);
+		priv_tx = entry->priv_data;
+		rt2x00_desc_read(priv_tx->desc, 0, &word);
 
 		if (rt2x00_get_field32(word, TXD_W0_OWNER_NIC) ||
 		    !rt2x00_get_field32(word, TXD_W0_VALID))
@@ -1117,10 +1116,10 @@
 		/*
 		 * Obtain the status about this packet.
 		 */
-		tx_status = rt2x00_get_field32(word, TXD_W0_RESULT);
-		retry = rt2x00_get_field32(word, TXD_W0_RETRY_COUNT);
+		txdesc.status = rt2x00_get_field32(word, TXD_W0_RESULT);
+		txdesc.retry = rt2x00_get_field32(word, TXD_W0_RETRY_COUNT);
 
-		rt2x00pci_txdone(rt2x00dev, entry, tx_status, retry);
+		rt2x00pci_txdone(rt2x00dev, entry, &txdesc);
 	}
 }
 
@@ -1374,9 +1373,9 @@
 	rt2400pci_probe_hw_mode(rt2x00dev);
 
 	/*
-	 * This device requires the beacon ring
+	 * This device requires the atim queue
 	 */
-	__set_bit(DRIVER_REQUIRE_BEACON_RING, &rt2x00dev->flags);
+	__set_bit(DRIVER_REQUIRE_ATIM_QUEUE, &rt2x00dev->flags);
 
 	/*
 	 * Set the rssi offset.
@@ -1481,7 +1480,8 @@
 	/*
 	 * Write configuration to register.
 	 */
-	rt2400pci_config_cw(rt2x00dev, &rt2x00dev->tx->tx_params);
+	rt2400pci_config_cw(rt2x00dev,
+			    rt2x00dev->tx->cw_min, rt2x00dev->tx->cw_max);
 
 	return 0;
 }
@@ -1560,12 +1560,42 @@
 	.config			= rt2400pci_config,
 };
 
+static const struct data_queue_desc rt2400pci_queue_rx = {
+	.entry_num		= RX_ENTRIES,
+	.data_size		= DATA_FRAME_SIZE,
+	.desc_size		= RXD_DESC_SIZE,
+	.priv_size		= sizeof(struct queue_entry_priv_pci_rx),
+};
+
+static const struct data_queue_desc rt2400pci_queue_tx = {
+	.entry_num		= TX_ENTRIES,
+	.data_size		= DATA_FRAME_SIZE,
+	.desc_size		= TXD_DESC_SIZE,
+	.priv_size		= sizeof(struct queue_entry_priv_pci_tx),
+};
+
+static const struct data_queue_desc rt2400pci_queue_bcn = {
+	.entry_num		= BEACON_ENTRIES,
+	.data_size		= MGMT_FRAME_SIZE,
+	.desc_size		= TXD_DESC_SIZE,
+	.priv_size		= sizeof(struct queue_entry_priv_pci_tx),
+};
+
+static const struct data_queue_desc rt2400pci_queue_atim = {
+	.entry_num		= ATIM_ENTRIES,
+	.data_size		= DATA_FRAME_SIZE,
+	.desc_size		= TXD_DESC_SIZE,
+	.priv_size		= sizeof(struct queue_entry_priv_pci_tx),
+};
+
 static const struct rt2x00_ops rt2400pci_ops = {
 	.name		= KBUILD_MODNAME,
-	.rxd_size	= RXD_DESC_SIZE,
-	.txd_size	= TXD_DESC_SIZE,
 	.eeprom_size	= EEPROM_SIZE,
 	.rf_size	= RF_SIZE,
+	.rx		= &rt2400pci_queue_rx,
+	.tx		= &rt2400pci_queue_tx,
+	.bcn		= &rt2400pci_queue_bcn,
+	.atim		= &rt2400pci_queue_atim,
 	.lib		= &rt2400pci_rt2x00_ops,
 	.hw		= &rt2400pci_mac80211_ops,
 #ifdef CONFIG_RT2X00_LIB_DEBUGFS