3 files changed, 22 insertions, 13 deletions

diff --git a/drivers/net/wireless/iwlwifi/iwl-agn.c b/drivers/net/wireless/iwlwifi/iwl-agn.c
index 6751bb2b8ae2..444c5cc05f03 100644
--- a/drivers/net/wireless/iwlwifi/iwl-agn.c
+++ b/drivers/net/wireless/iwlwifi/iwl-agn.c
@@ -1384,7 +1384,7 @@ void iwl_rx_handle(struct iwl_priv *priv)
 
                 rxq->queue[i] = NULL;
 
-                pci_dma_sync_single_for_cpu(priv->pci_dev, rxb->dma_addr,
+                pci_dma_sync_single_for_cpu(priv->pci_dev, rxb->aligned_dma_addr,
                                             priv->hw_params.rx_buf_size,
                                             PCI_DMA_FROMDEVICE);
                 pkt = (struct iwl_rx_packet *)rxb->skb->data;
@@ -1436,8 +1436,8 @@ void iwl_rx_handle(struct iwl_priv *priv)
                         rxb->skb = NULL;
                 }
 
-                pci_unmap_single(priv->pci_dev, rxb->dma_addr,
-                                 priv->hw_params.rx_buf_size,
+                pci_unmap_single(priv->pci_dev, rxb->real_dma_addr,
+                                 priv->hw_params.rx_buf_size + 256,
                                  PCI_DMA_FROMDEVICE);
                 spin_lock_irqsave(&rxq->lock, flags);
                 list_add_tail(&rxb->list, &priv->rxq.rx_used);
diff --git a/drivers/net/wireless/iwlwifi/iwl-dev.h b/drivers/net/wireless/iwlwifi/iwl-dev.h
index c018121085e9..9966d4e384ce 100644
--- a/drivers/net/wireless/iwlwifi/iwl-dev.h
+++ b/drivers/net/wireless/iwlwifi/iwl-dev.h
@@ -89,7 +89,8 @@ extern struct iwl_cfg iwl5100_abg_cfg;
 #define DEFAULT_LONG_RETRY_LIMIT  4U
 
 struct iwl_rx_mem_buffer {
-        dma_addr_t dma_addr;
+        dma_addr_t real_dma_addr;
+        dma_addr_t aligned_dma_addr;
         struct sk_buff *skb;
         struct list_head list;
 };
diff --git a/drivers/net/wireless/iwlwifi/iwl-rx.c b/drivers/net/wireless/iwlwifi/iwl-rx.c
index 7cde9d76ff5d..0509c16dbe75 100644
--- a/drivers/net/wireless/iwlwifi/iwl-rx.c
+++ b/drivers/net/wireless/iwlwifi/iwl-rx.c
@@ -204,7 +204,7 @@ int iwl_rx_queue_restock(struct iwl_priv *priv)
                 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->bd[rxq->write] = iwl_dma_addr2rbd_ptr(priv, rxb->aligned_dma_addr);
                 rxq->queue[rxq->write] = rxb;
                 rxq->write = (rxq->write + 1) & RX_QUEUE_MASK;
                 rxq->free_count--;
@@ -251,7 +251,7 @@ void iwl_rx_allocate(struct iwl_priv *priv)
                 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,
+                rxb->skb = alloc_skb(priv->hw_params.rx_buf_size + 256,
                                 __GFP_NOWARN | GFP_ATOMIC);
                 if (!rxb->skb) {
                         if (net_ratelimit())
@@ -266,9 +266,17 @@ void iwl_rx_allocate(struct iwl_priv *priv)
                 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);
+                rxb->real_dma_addr = pci_map_single(
+                                        priv->pci_dev,
+                                        rxb->skb->data,
+                                        priv->hw_params.rx_buf_size + 256,
+                                        PCI_DMA_FROMDEVICE);
+                /* dma address must be no more than 36 bits */
+                BUG_ON(rxb->real_dma_addr & ~DMA_BIT_MASK(36));
+                /* and also 256 byte aligned! */
+                rxb->aligned_dma_addr = ALIGN(rxb->real_dma_addr, 256);
+                skb_reserve(rxb->skb, rxb->aligned_dma_addr - rxb->real_dma_addr);
+
                 list_add_tail(&rxb->list, &rxq->rx_free);
                 rxq->free_count++;
         }
@@ -300,8 +308,8 @@ void iwl_rx_queue_free(struct iwl_priv *priv, struct iwl_rx_queue *rxq)
         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,
+                                         rxq->pool[i].real_dma_addr,
+                                         priv->hw_params.rx_buf_size + 256,
                                          PCI_DMA_FROMDEVICE);
                         dev_kfree_skb(rxq->pool[i].skb);
                 }
@@ -354,8 +362,8 @@ void iwl_rx_queue_reset(struct iwl_priv *priv, struct iwl_rx_queue *rxq)
                  * 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,
+                                         rxq->pool[i].real_dma_addr,
+                                         priv->hw_params.rx_buf_size + 256,
                                          PCI_DMA_FROMDEVICE);
                         priv->alloc_rxb_skb--;
                         dev_kfree_skb(rxq->pool[i].skb);