iwlwifi: move RX code to iwl-rx.c

This patch moves partialy rx code into iwl-rx.c as part of iwlcore.
The second part of the code can be merged only with moving of tx
code as well.
Signed-off-by: NTomas Winkler <tomas.winkler@intel.com>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

drivers/net/wireless/iwlwifi/Makefile

 obj-$(CONFIG_IWLCORE)	+= iwlcore.o
 iwlcore-objs 		:= iwl-core.o iwl-eeprom.o iwl-hcmd.o iwl-power.o
+iwlcore-objs 		+= iwl-rx.o
 iwlcore-$(CONFIG_IWLWIFI_DEBUGFS) += iwl-debugfs.o
 iwlcore-$(CONFIG_IWLWIFI_LEDS) += iwl-led.o
 iwlcore-$(CONFIG_IWLWIFI_RFKILL) += iwl-rfkill.o

drivers/net/wireless/iwlwifi/iwl-4965.c

@@ -372,7 +372,7 @@ int iwl4965_set_pwr_src(struct iwl_priv *priv, enum iwl_pwr_src src)
 	return ret;
 }
 
-static int iwl4965_rx_init(struct iwl_priv *priv, struct iwl4965_rx_queue *rxq)
+static int iwl4965_rx_init(struct iwl_priv *priv, struct iwl_rx_queue *rxq)
 {
 	int ret;
 	unsigned long flags;
@@ -625,7 +625,7 @@ static void iwl4965_nic_config(struct iwl_priv *priv)
 int iwl4965_hw_nic_init(struct iwl_priv *priv)
 {
 	unsigned long flags;
-	struct iwl4965_rx_queue *rxq = &priv->rxq;
+	struct iwl_rx_queue *rxq = &priv->rxq;
 	int ret;
 
 	/* nic_init */
@@ -645,22 +645,22 @@ int iwl4965_hw_nic_init(struct iwl_priv *priv)
 
 	/* Allocate the RX queue, or reset if it is already allocated */
 	if (!rxq->bd) {
-		ret = iwl4965_rx_queue_alloc(priv);
+		ret = iwl_rx_queue_alloc(priv);
 		if (ret) {
 			IWL_ERROR("Unable to initialize Rx queue\n");
 			return -ENOMEM;
 		}
 	} else
-		iwl4965_rx_queue_reset(priv, rxq);
+		iwl_rx_queue_reset(priv, rxq);
 
-	iwl4965_rx_replenish(priv);
+	iwl_rx_replenish(priv);
 
 	iwl4965_rx_init(priv, rxq);
 
 	spin_lock_irqsave(&priv->lock, flags);
 
 	rxq->need_update = 1;
-	iwl4965_rx_queue_update_write_ptr(priv, rxq);
+	iwl_rx_queue_update_write_ptr(priv, rxq);
 
 	spin_unlock_irqrestore(&priv->lock, flags);
 
@@ -2516,7 +2516,8 @@ static void iwl4965_rx_calc_noise(struct iwl_priv *priv)
 			priv->last_rx_noise);
 }
 
-void iwl4965_hw_rx_statistics(struct iwl_priv *priv, struct iwl4965_rx_mem_buffer *rxb)
+void iwl4965_hw_rx_statistics(struct iwl_priv *priv,
+			      struct iwl_rx_mem_buffer *rxb)
 {
 	struct iwl4965_rx_packet *pkt = (void *)rxb->skb->data;
 	int change;
@@ -2803,7 +2804,7 @@ static u32 iwl4965_translate_rx_status(u32 decrypt_in)
 
 static void iwl4965_handle_data_packet(struct iwl_priv *priv, int is_data,
 				       int include_phy,
-				       struct iwl4965_rx_mem_buffer *rxb,
+				       struct iwl_rx_mem_buffer *rxb,
 				       struct ieee80211_rx_status *stats)
 {
 	struct iwl4965_rx_packet *pkt = (struct iwl4965_rx_packet *)rxb->skb->data;
@@ -3109,7 +3110,7 @@ static inline void iwl4965_dbg_report_frame(struct iwl_priv *priv,
 /* Called for REPLY_RX (legacy ABG frames), or
  * REPLY_RX_MPDU_CMD (HT high-throughput N frames). */
 static void iwl4965_rx_reply_rx(struct iwl_priv *priv,
-				struct iwl4965_rx_mem_buffer *rxb)
+				struct iwl_rx_mem_buffer *rxb)
 {
 	struct ieee80211_hdr *header;
 	struct ieee80211_rx_status rx_status;
@@ -3278,7 +3279,7 @@ static void iwl4965_rx_reply_rx(struct iwl_priv *priv,
 /* Cache phy data (Rx signal strength, etc) for HT frame (REPLY_RX_PHY_CMD).
  * This will be used later in iwl4965_rx_reply_rx() for REPLY_RX_MPDU_CMD. */
 static void iwl4965_rx_reply_rx_phy(struct iwl_priv *priv,
-				    struct iwl4965_rx_mem_buffer *rxb)
+				    struct iwl_rx_mem_buffer *rxb)
 {
 	struct iwl4965_rx_packet *pkt = (void *)rxb->skb->data;
 	priv->last_phy_res[0] = 1;
@@ -3286,7 +3287,7 @@ static void iwl4965_rx_reply_rx_phy(struct iwl_priv *priv,
 	       sizeof(struct iwl4965_rx_phy_res));
 }
 static void iwl4965_rx_missed_beacon_notif(struct iwl_priv *priv,
-					   struct iwl4965_rx_mem_buffer *rxb)
+					   struct iwl_rx_mem_buffer *rxb)
 
 {
 #ifdef CONFIG_IWL4965_RUN_TIME_CALIB
@@ -3495,7 +3496,7 @@ static inline int iwl4965_queue_dec_wrap(int index, int n_bd)
  * of frames sent via aggregation.
  */
 static void iwl4965_rx_reply_compressed_ba(struct iwl_priv *priv,
-					   struct iwl4965_rx_mem_buffer *rxb)
+					   struct iwl_rx_mem_buffer *rxb)
 {
 	struct iwl4965_rx_packet *pkt = (void *)rxb->skb->data;
 	struct iwl4965_compressed_ba_resp *ba_resp = &pkt->u.compressed_ba;

drivers/net/wireless/iwlwifi/iwl-core.h

@@ -173,6 +173,21 @@ int iwl_set_rxon_channel(struct iwl_priv *priv,
 void iwlcore_free_geos(struct iwl_priv *priv);
 int iwl_setup(struct iwl_priv *priv);
 
+/*****************************************************
+* RX
+******************************************************/
+void iwl_rx_queue_free(struct iwl_priv *priv, struct iwl_rx_queue *rxq);
+int iwl_rx_queue_alloc(struct iwl_priv *priv);
+void iwl_rx_handle(struct iwl_priv *priv);
+int iwl_rx_queue_update_write_ptr(struct iwl_priv *priv,
+				  struct iwl_rx_queue *q);
+void iwl_rx_queue_reset(struct iwl_priv *priv, struct iwl_rx_queue *rxq);
+void iwl_rx_replenish(struct iwl_priv *priv);
+/* FIXME: remove when TX is moved to iwl core */
+int iwl_rx_queue_restock(struct iwl_priv *priv);
+int iwl_rx_queue_space(const struct iwl_rx_queue *q);
+void iwl_rx_allocate(struct iwl_priv *priv);
+
 /*****************************************************
  *   S e n d i n g     H o s t     C o m m a n d s   *
  *****************************************************/
@@ -265,4 +280,5 @@ static inline int iwl_send_rxon_assoc(struct iwl_priv *priv)
 	return priv->cfg->ops->hcmd->rxon_assoc(priv);
 }
 
+
 #endif /* __iwl_core_h__ */

drivers/net/wireless/iwlwifi/iwl-dev.h

@@ -91,7 +91,7 @@ extern struct iwl_cfg iwl5350_agn_cfg;
 #define	DEFAULT_SHORT_RETRY_LIMIT 7U
 #define	DEFAULT_LONG_RETRY_LIMIT  4U
 
-struct iwl4965_rx_mem_buffer {
+struct iwl_rx_mem_buffer {
 	dma_addr_t dma_addr;
 	struct sk_buff *skb;
 	struct list_head list;
@@ -358,7 +358,7 @@ struct iwl_host_cmd {
 #define SUP_RATE_11G_MAX_NUM_CHANNELS  12
 
 /**
- * struct iwl4965_rx_queue - Rx queue
+ * struct iwl_rx_queue - Rx queue
  * @processed: Internal index to last handled Rx packet
  * @read: Shared index to newest available Rx buffer
  * @write: Shared index to oldest written Rx packet
@@ -367,13 +367,13 @@ struct iwl_host_cmd {
  * @rx_used: List of Rx buffers with no SKB
  * @need_update: flag to indicate we need to update read/write index
  *
- * NOTE:  rx_free and rx_used are used as a FIFO for iwl4965_rx_mem_buffers
+ * NOTE:  rx_free and rx_used are used as a FIFO for iwl_rx_mem_buffers
  */
-struct iwl4965_rx_queue {
+struct iwl_rx_queue {
 	__le32 *bd;
 	dma_addr_t dma_addr;
-	struct iwl4965_rx_mem_buffer pool[RX_QUEUE_SIZE + RX_FREE_BUFFERS];
-	struct iwl4965_rx_mem_buffer *queue[RX_QUEUE_SIZE];
+	struct iwl_rx_mem_buffer pool[RX_QUEUE_SIZE + RX_FREE_BUFFERS];
+	struct iwl_rx_mem_buffer *queue[RX_QUEUE_SIZE];
 	u32 processed;
 	u32 read;
 	u32 write;
@@ -643,26 +643,20 @@ extern int iwl4965_is_network_packet(struct iwl_priv *priv,
 				 struct ieee80211_hdr *header);
 extern int iwl4965_power_init_handle(struct iwl_priv *priv);
 extern void iwl4965_handle_data_packet_monitor(struct iwl_priv *priv,
-					   struct iwl4965_rx_mem_buffer *rxb,
+					   struct iwl_rx_mem_buffer *rxb,
 					   void *data, short len,
 					   struct ieee80211_rx_status *stats,
 					   u16 phy_flags);
 extern int iwl4965_is_duplicate_packet(struct iwl_priv *priv,
 				       struct ieee80211_hdr *header);
-extern int iwl4965_rx_queue_alloc(struct iwl_priv *priv);
-extern void iwl4965_rx_queue_reset(struct iwl_priv *priv,
-			       struct iwl4965_rx_queue *rxq);
 extern int iwl4965_calc_db_from_ratio(int sig_ratio);
 extern int iwl4965_calc_sig_qual(int rssi_dbm, int noise_dbm);
 extern int iwl4965_tx_queue_init(struct iwl_priv *priv,
 			     struct iwl4965_tx_queue *txq, int count, u32 id);
-extern void iwl4965_rx_replenish(void *data);
 extern void iwl4965_tx_queue_free(struct iwl_priv *priv, struct iwl4965_tx_queue *txq);
 extern unsigned int iwl4965_fill_beacon_frame(struct iwl_priv *priv,
 					struct ieee80211_hdr *hdr,
 					const u8 *dest, int left);
-extern int iwl4965_rx_queue_update_write_ptr(struct iwl_priv *priv,
-					 struct iwl4965_rx_queue *q);
 extern __le16 *ieee80211_get_qos_ctrl(struct ieee80211_hdr *hdr);
 extern void iwl4965_update_chain_flags(struct iwl_priv *priv);
 int iwl4965_set_pwr_src(struct iwl_priv *priv, enum iwl_pwr_src src);
@@ -722,7 +716,7 @@ extern void iwl4965_hw_build_tx_cmd_rate(struct iwl_priv *priv,
 extern int iwl4965_hw_reg_send_txpower(struct iwl_priv *priv);
 extern int iwl4965_hw_reg_set_txpower(struct iwl_priv *priv, s8 power);
 extern void iwl4965_hw_rx_statistics(struct iwl_priv *priv,
-				 struct iwl4965_rx_mem_buffer *rxb);
+				 struct iwl_rx_mem_buffer *rxb);
 extern void iwl4965_disable_events(struct iwl_priv *priv);
 extern int iwl4965_get_temperature(const struct iwl_priv *priv);
 
@@ -960,7 +954,7 @@ struct iwl_priv {
 	bool add_radiotap;
 
 	void (*rx_handlers[REPLY_MAX])(struct iwl_priv *priv,
-				       struct iwl4965_rx_mem_buffer *rxb);
+				       struct iwl_rx_mem_buffer *rxb);
 
 	struct ieee80211_supported_band bands[IEEE80211_NUM_BANDS];
 
@@ -1077,7 +1071,7 @@ struct iwl_priv {
 	int activity_timer_active;
 
 	/* Rx and Tx DMA processing queues */
-	struct iwl4965_rx_queue rxq;
+	struct iwl_rx_queue rxq;
 	struct iwl4965_tx_queue txq[IWL_MAX_NUM_QUEUES];
 	unsigned long txq_ctx_active_msk;
 	struct iwl4965_kw kw;	/* keep warm address */

drivers/net/wireless/iwlwifi/iwl-rx.c

+/******************************************************************************
+ *
+ * Copyright(c) 2003 - 2008 Intel Corporation. All rights reserved.
+ *
+ * Portions of this file are derived from the ipw3945 project, as well
+ * as portions of the ieee80211 subsystem header files.
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of version 2 of the GNU General Public License as
+ * published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
+ * more details.
+ *
+ * You should have received a copy of the GNU General Public License along with
+ * this program; if not, write to the Free Software Foundation, Inc.,
+ * 51 Franklin Street, Fifth Floor, Boston, MA 02110, USA
+ *
+ * The full GNU General Public License is included in this distribution in the
+ * file called LICENSE.
+ *
+ * Contact Information:
+ * James P. Ketrenos <ipw2100-admin@linux.intel.com>
+ * Intel Corporation, 5200 N.E. Elam Young Parkway, Hillsboro, OR 97124-6497
+ *
+ *****************************************************************************/
+
+#include <net/mac80211.h>
+#include "iwl-eeprom.h"
+#include "iwl-dev.h"
+#include "iwl-core.h"
+#include "iwl-sta.h"
+#include "iwl-io.h"
+#include "iwl-helpers.h"
+/************************** RX-FUNCTIONS ****************************/
+/*
+ * Rx theory of operation
+ *
+ * Driver allocates a circular buffer of Receive Buffer Descriptors (RBDs),
+ * each of which point to Receive Buffers to be filled by the NIC.  These get
+ * used not only for Rx frames, but for any command response or notification
+ * from the NIC.  The driver and NIC manage the Rx buffers by means
+ * of indexes into the circular buffer.
+ *
+ * Rx Queue Indexes
+ * The host/firmware share two index registers for managing the Rx buffers.
+ *
+ * The READ index maps to the first position that the firmware may be writing
+ * to -- the driver can read up to (but not including) this position and get
+ * good data.
+ * The READ index is managed by the firmware once the card is enabled.
+ *
+ * The WRITE index maps to the last position the driver has read from -- the
+ * position preceding WRITE is the last slot the firmware can place a packet.
+ *
+ * The queue is empty (no good data) if WRITE = READ - 1, and is full if
+ * WRITE = READ.
+ *
+ * During initialization, the host sets up the READ queue position to the first
+ * INDEX position, and WRITE to the last (READ - 1 wrapped)
+ *
+ * When the firmware places a packet in a buffer, it will advance the READ index
+ * and fire the RX interrupt.  The driver can then query the READ index and
+ * process as many packets as possible, moving the WRITE index forward as it
+ * resets the Rx queue buffers with new memory.
+ *
+ * The management in the driver is as follows:
+ * + A list of pre-allocated SKBs is stored in iwl->rxq->rx_free.  When
+ *   iwl->rxq->free_count drops to or below RX_LOW_WATERMARK, work is scheduled
+ *   to replenish the iwl->rxq->rx_free.
+ * + In iwl_rx_replenish (scheduled) if 'processed' != 'read' then the
+ *   iwl->rxq is replenished and the READ INDEX is updated (updating the
+ *   'processed' and 'read' driver indexes as well)
+ * + A received packet is processed and handed to the kernel network stack,
+ *   detached from the iwl->rxq.  The driver 'processed' index is updated.
+ * + The Host/Firmware iwl->rxq is replenished at tasklet time from the rx_free
+ *   list. If there are no allocated buffers in iwl->rxq->rx_free, the READ
+ *   INDEX is not incremented and iwl->status(RX_STALLED) is set.  If there
+ *   were enough free buffers and RX_STALLED is set it is cleared.
+ *
+ *
+ * Driver sequence:
+ *
+ * iwl_rx_queue_alloc()   Allocates rx_free
+ * iwl_rx_replenish()     Replenishes rx_free list from rx_used, and calls
+ *                            iwl_rx_queue_restock
+ * iwl_rx_queue_restock() Moves available buffers from rx_free into Rx
+ *                            queue, updates firmware pointers, and updates
+ *                            the WRITE index.  If insufficient rx_free buffers
+ *                            are available, schedules iwl_rx_replenish
+ *
+ * -- enable interrupts --
+ * ISR - iwl_rx()         Detach iwl_rx_mem_buffers from pool up to the
+ *                            READ INDEX, detaching the SKB from the pool.
+ *                            Moves the packet buffer from queue to rx_used.
+ *                            Calls iwl_rx_queue_restock to refill any empty
+ *                            slots.
+ * ...
+ *
+ */
+
+/**
+ * iwl_rx_queue_space - Return number of free slots available in queue.
+ */
+int iwl_rx_queue_space(const struct iwl_rx_queue *q)
+{
+	int s = q->read - q->write;
+	if (s <= 0)
+		s += RX_QUEUE_SIZE;
+	/* keep some buffer to not confuse full and empty queue */
+	s -= 2;
+	if (s < 0)
+		s = 0;
+	return s;
+}
+EXPORT_SYMBOL(iwl_rx_queue_space);
+
+/**
+ * iwl_rx_queue_update_write_ptr - Update the write pointer for the RX queue
+ */
+int iwl_rx_queue_update_write_ptr(struct iwl_priv *priv, struct iwl_rx_queue *q)
+{
+	u32 reg = 0;
+	int ret = 0;
+	unsigned long flags;
+
+	spin_lock_irqsave(&q->lock, flags);
+
+	if (q->need_update == 0)
+		goto exit_unlock;
+
+	/* If power-saving is in use, make sure device is awake */
+	if (test_bit(STATUS_POWER_PMI, &priv->status)) {
+		reg = iwl_read32(priv, CSR_UCODE_DRV_GP1);
+
+		if (reg & CSR_UCODE_DRV_GP1_BIT_MAC_SLEEP) {
+			iwl_set_bit(priv, CSR_GP_CNTRL,
+				    CSR_GP_CNTRL_REG_FLAG_MAC_ACCESS_REQ);
+			goto exit_unlock;
+		}
+
+		ret = iwl_grab_nic_access(priv);
+		if (ret)
+			goto exit_unlock;
+
+		/* Device expects a multiple of 8 */
+		iwl_write_direct32(priv, FH_RSCSR_CHNL0_WPTR,
+				     q->write & ~0x7);
+		iwl_release_nic_access(priv);
+
+	/* Else device is assumed to be awake */
+	} else
+		/* Device expects a multiple of 8 */
+		iwl_write32(priv, FH_RSCSR_CHNL0_WPTR, q->write & ~0x7);
+
+
+	q->need_update = 0;
+
+ exit_unlock:
+	spin_unlock_irqrestore(&q->lock, flags);
+	return ret;
+}
+EXPORT_SYMBOL(iwl_rx_queue_update_write_ptr);
+/**
+ * iwl_dma_addr2rbd_ptr - convert a DMA address to a uCode read buffer ptr
+ */
+static inline __le32 iwl_dma_addr2rbd_ptr(struct iwl_priv *priv,
+					  dma_addr_t dma_addr)
+{
+	return cpu_to_le32((u32)(dma_addr >> 8));
+}
+
+/**
+ * iwl_rx_queue_restock - refill RX queue from pre-allocated pool
+ *
+ * If there are slots in the RX queue that need to be restocked,
+ * and we have free pre-allocated buffers, fill the ranks as much
+ * as we can, pulling from rx_free.
+ *
+ * This moves the 'write' index forward to catch up with 'processed', and
+ * also updates the memory address in the firmware to reference the new
+ * target buffer.
+ */
+int iwl_rx_queue_restock(struct iwl_priv *priv)
+{
+	struct iwl_rx_queue *rxq = &priv->rxq;
+	struct list_head *element;
+	struct iwl_rx_mem_buffer *rxb;
+	unsigned long flags;
+	int write;
+	int ret = 0;
+
+	spin_lock_irqsave(&rxq->lock, flags);
+	write = rxq->write & ~0x7;
+	while ((iwl_rx_queue_space(rxq) > 0) && (rxq->free_count)) {
+		/* Get next free Rx buffer, remove from free list */
+		element = rxq->rx_free.next;
+		rxb = list_entry(element, struct iwl_rx_mem_buffer, list);
+		list_del(element);
+
+		/* Point to Rx buffer via next RBD in circular buffer */
+		rxq->bd[rxq->write] = iwl_dma_addr2rbd_ptr(priv, rxb->dma_addr);
+		rxq->queue[rxq->write] = rxb;
+		rxq->write = (rxq->write + 1) & RX_QUEUE_MASK;
+		rxq->free_count--;
+	}
+	spin_unlock_irqrestore(&rxq->lock, flags);
+	/* If the pre-allocated buffer pool is dropping low, schedule to
+	 * refill it */
+	if (rxq->free_count <= RX_LOW_WATERMARK)
+		queue_work(priv->workqueue, &priv->rx_replenish);
+
+
+	/* If we've added more space for the firmware to place data, tell it.
+	 * Increment device's write pointer in multiples of 8. */
+	if ((write != (rxq->write & ~0x7))
+	    || (abs(rxq->write - rxq->read) > 7)) {
+		spin_lock_irqsave(&rxq->lock, flags);
+		rxq->need_update = 1;
+		spin_unlock_irqrestore(&rxq->lock, flags);
+		ret = iwl_rx_queue_update_write_ptr(priv, rxq);
+	}
+
+	return ret;
+}
+EXPORT_SYMBOL(iwl_rx_queue_restock);
+
+
+/**
+ * iwl_rx_replenish - Move all used packet from rx_used to rx_free
+ *
+ * When moving to rx_free an SKB is allocated for the slot.
+ *
+ * Also restock the Rx queue via iwl_rx_queue_restock.
+ * This is called as a scheduled work item (except for during initialization)
+ */
+void iwl_rx_allocate(struct iwl_priv *priv)
+{
+	struct iwl_rx_queue *rxq = &priv->rxq;
+	struct list_head *element;
+	struct iwl_rx_mem_buffer *rxb;
+	unsigned long flags;
+	spin_lock_irqsave(&rxq->lock, flags);
+	while (!list_empty(&rxq->rx_used)) {
+		element = rxq->rx_used.next;
+		rxb = list_entry(element, struct iwl_rx_mem_buffer, list);
+
+		/* Alloc a new receive buffer */
+		rxb->skb = alloc_skb(priv->hw_params.rx_buf_size,
+				__GFP_NOWARN | GFP_ATOMIC);
+		if (!rxb->skb) {
+			if (net_ratelimit())
+				printk(KERN_CRIT DRV_NAME
+				       ": Can not allocate SKB buffers\n");
+			/* We don't reschedule replenish work here -- we will
+			 * call the restock method and if it still needs
+			 * more buffers it will schedule replenish */
+			break;
+		}
+		priv->alloc_rxb_skb++;
+		list_del(element);
+
+		/* Get physical address of RB/SKB */
+		rxb->dma_addr =
+		    pci_map_single(priv->pci_dev, rxb->skb->data,
+			   priv->hw_params.rx_buf_size, PCI_DMA_FROMDEVICE);
+		list_add_tail(&rxb->list, &rxq->rx_free);
+		rxq->free_count++;
+	}
+	spin_unlock_irqrestore(&rxq->lock, flags);
+}
+EXPORT_SYMBOL(iwl_rx_allocate);
+
+void iwl_rx_replenish(struct iwl_priv *priv)
+{
+	unsigned long flags;
+
+	iwl_rx_allocate(priv);
+
+	spin_lock_irqsave(&priv->lock, flags);
+	iwl_rx_queue_restock(priv);
+	spin_unlock_irqrestore(&priv->lock, flags);
+}
+EXPORT_SYMBOL(iwl_rx_replenish);
+
+
+/* Assumes that the skb field of the buffers in 'pool' is kept accurate.
+ * If an SKB has been detached, the POOL needs to have its SKB set to NULL
+ * This free routine walks the list of POOL entries and if SKB is set to
+ * non NULL it is unmapped and freed
+ */
+void iwl_rx_queue_free(struct iwl_priv *priv, struct iwl_rx_queue *rxq)
+{
+	int i;
+	for (i = 0; i < RX_QUEUE_SIZE + RX_FREE_BUFFERS; i++) {
+		if (rxq->pool[i].skb != NULL) {
+			pci_unmap_single(priv->pci_dev,
+					 rxq->pool[i].dma_addr,
+					 priv->hw_params.rx_buf_size,
+					 PCI_DMA_FROMDEVICE);
+			dev_kfree_skb(rxq->pool[i].skb);
+		}
+	}
+
+	pci_free_consistent(priv->pci_dev, 4 * RX_QUEUE_SIZE, rxq->bd,
+			    rxq->dma_addr);
+	rxq->bd = NULL;
+}
+EXPORT_SYMBOL(iwl_rx_queue_free);
+
+int iwl_rx_queue_alloc(struct iwl_priv *priv)
+{
+	struct iwl_rx_queue *rxq = &priv->rxq;
+	struct pci_dev *dev = priv->pci_dev;
+	int i;
+
+	spin_lock_init(&rxq->lock);
+	INIT_LIST_HEAD(&rxq->rx_free);
+	INIT_LIST_HEAD(&rxq->rx_used);
+
+	/* Alloc the circular buffer of Read Buffer Descriptors (RBDs) */
+	rxq->bd = pci_alloc_consistent(dev, 4 * RX_QUEUE_SIZE, &rxq->dma_addr);
+	if (!rxq->bd)
+		return -ENOMEM;
+
+	/* Fill the rx_used queue with _all_ of the Rx buffers */
+	for (i = 0; i < RX_FREE_BUFFERS + RX_QUEUE_SIZE; i++)
+		list_add_tail(&rxq->pool[i].list, &rxq->rx_used);
+
+	/* Set us so that we have processed and used all buffers, but have
+	 * not restocked the Rx queue with fresh buffers */
+	rxq->read = rxq->write = 0;
+	rxq->free_count = 0;
+	rxq->need_update = 0;
+	return 0;
+}
+EXPORT_SYMBOL(iwl_rx_queue_alloc);
+
+void iwl_rx_queue_reset(struct iwl_priv *priv, struct iwl_rx_queue *rxq)
+{
+	unsigned long flags;
+	int i;
+	spin_lock_irqsave(&rxq->lock, flags);
+	INIT_LIST_HEAD(&rxq->rx_free);
+	INIT_LIST_HEAD(&rxq->rx_used);
+	/* Fill the rx_used queue with _all_ of the Rx buffers */
+	for (i = 0; i < RX_FREE_BUFFERS + RX_QUEUE_SIZE; i++) {
+		/* In the reset function, these buffers may have been allocated
+		 * to an SKB, so we need to unmap and free potential storage */
+		if (rxq->pool[i].skb != NULL) {
+			pci_unmap_single(priv->pci_dev,
+					 rxq->pool[i].dma_addr,
+					 priv->hw_params.rx_buf_size,
+					 PCI_DMA_FROMDEVICE);
+			priv->alloc_rxb_skb--;
+			dev_kfree_skb(rxq->pool[i].skb);
+			rxq->pool[i].skb = NULL;
+		}
+		list_add_tail(&rxq->pool[i].list, &rxq->rx_used);
+	}
+
+	/* Set us so that we have processed and used all buffers, but have
+	 * not restocked the Rx queue with fresh buffers */
+	rxq->read = rxq->write = 0;
+	rxq->free_count = 0;
+	spin_unlock_irqrestore(&rxq->lock, flags);
+}
+EXPORT_SYMBOL(iwl_rx_queue_reset);
+