iwl3945: fix lock dependency

Patch seperates rx_used and rx_free into two
different atomic contexts. We can now avoid using GFP_ATOMIC
for skb allocation and use GFP_KERNEL.

Signed-off-by: Abhijeet Kolekar <abhijeet.kolekar@intel.com>
Signed-off-by: Reinette Chatre <reinette.chatre@intel.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

1 files changed, 17 insertions, 20 deletions

diff --git a/drivers/net/wireless/iwlwifi/iwl3945-base.c b/drivers/net/wireless/iwlwifi/iwl3945-base.c
index 5cd4321d7cf5..dc0359ce1ec0 100644
--- a/drivers/net/wireless/iwlwifi/iwl3945-base.c
+++ b/drivers/net/wireless/iwlwifi/iwl3945-base.c
@@ -1344,15 +1344,24 @@ static void iwl3945_rx_allocate(struct iwl_priv *priv)
         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)) {
+
+        while (1) {
+                spin_lock_irqsave(&rxq->lock, flags);
+
+                if (list_empty(&rxq->rx_used)) {
+                        spin_unlock_irqrestore(&rxq->lock, flags);
+                        return;
+                }
+
                 element = rxq->rx_used.next;
                 rxb = list_entry(element, struct iwl_rx_mem_buffer, list);
+                list_del(element);
+                spin_unlock_irqrestore(&rxq->lock, flags);
 
                 /* Alloc a new receive buffer */
                 rxb->skb =
                     alloc_skb(priv->hw_params.rx_buf_size,
-                                __GFP_NOWARN | GFP_ATOMIC);
+                                GFP_KERNEL);
                 if (!rxb->skb) {
                         if (net_ratelimit())
                                 IWL_CRIT(priv, ": Can not allocate SKB buffers\n");
@@ -1370,18 +1379,18 @@ static void iwl3945_rx_allocate(struct iwl_priv *priv)
                  */
                 skb_reserve(rxb->skb, 4);
 
-                priv->alloc_rxb_skb++;
-                list_del(element);
-
                 /* Get physical address of RB/SKB */
                 rxb->real_dma_addr = pci_map_single(priv->pci_dev,
                                                 rxb->skb->data,
                                                 priv->hw_params.rx_buf_size,
                                                 PCI_DMA_FROMDEVICE);
+
+                spin_lock_irqsave(&rxq->lock, flags);
                 list_add_tail(&rxb->list, &rxq->rx_free);
+                priv->alloc_rxb_skb++;
                 rxq->free_count++;
+                spin_unlock_irqrestore(&rxq->lock, flags);
         }
-        spin_unlock_irqrestore(&rxq->lock, flags);
 }
 
 void iwl3945_rx_queue_reset(struct iwl_priv *priv, struct iwl_rx_queue *rxq)
@@ -1414,18 +1423,6 @@ void iwl3945_rx_queue_reset(struct iwl_priv *priv, struct iwl_rx_queue *rxq)
         spin_unlock_irqrestore(&rxq->lock, flags);
 }
 
-/*
- * this should be called while priv->lock is locked
- */
-static void __iwl3945_rx_replenish(void *data)
-{
-        struct iwl_priv *priv = data;
-
-        iwl3945_rx_allocate(priv);
-        iwl3945_rx_queue_restock(priv);
-}
-
-
 void iwl3945_rx_replenish(void *data)
 {
         struct iwl_priv *priv = data;
@@ -1644,7 +1641,7 @@ static void iwl3945_rx_handle(struct iwl_priv *priv)
                         count++;
                         if (count >= 8) {
                                 priv->rxq.read = i;
-                                __iwl3945_rx_replenish(priv);
+                                iwl3945_rx_queue_restock(priv);
                                 count = 0;
                         }
                 }