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>

diff --git a/drivers/net/wireless/iwlwifi/iwl3945-base.c b/drivers/net/wireless/iwlwifi/iwl3945-base.c
index 5cd4321..dc0359c 100644 (file)
--- 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;
                        }
                }