tlan: manage rx allocation failure better
authorStephen Hemminger <shemminger@vyatta.com>
Fri, 30 May 2008 16:49:56 +0000 (09:49 -0700)
committerJeff Garzik <jgarzik@redhat.com>
Sat, 31 May 2008 02:18:00 +0000 (22:18 -0400)
Rx allocation failure at runtime is non-fatal. For normal Rx frame, it
just reuses the buffer, and during setup it just continues with a smaller
receive buffer pool.

Compile tested only.

Signed-off-by: Stephen Hemminger <shemminger@vyatta.com>
Signed-off-by: Jeff Garzik <jgarzik@redhat.com>
drivers/net/tlan.c

index aee2a458adc3749066f4aed5877e86e3ac42535b..afc831002db27b1eb2b1e541c40524a73caee180 100644 (file)
@@ -1539,8 +1539,6 @@ static u32 TLan_HandleRxEOF( struct net_device *dev, u16 host_int )
        TLanList        *head_list;
        struct sk_buff  *skb;
        TLanList        *tail_list;
-       void            *t;
-       u32             frameSize;
        u16             tmpCStat;
        dma_addr_t      head_list_phys;
 
@@ -1549,40 +1547,34 @@ static u32 TLan_HandleRxEOF( struct net_device *dev, u16 host_int )
        head_list_phys = priv->rxListDMA + sizeof(TLanList) * priv->rxHead;
 
        while (((tmpCStat = head_list->cStat) & TLAN_CSTAT_FRM_CMP) && (ack < 255)) {
-               frameSize = head_list->frameSize;
+               dma_addr_t frameDma = head_list->buffer[0].address;
+               u32 frameSize = head_list->frameSize;
                ack++;
                if (tmpCStat & TLAN_CSTAT_EOC)
                        eoc = 1;
 
                if (bbuf) {
-                       skb = dev_alloc_skb(frameSize + 7);
-                       if (skb == NULL)
-                               printk(KERN_INFO "TLAN: Couldn't allocate memory for received data.\n");
-                       else {
+                       skb = netdev_alloc_skb(dev, frameSize + 7);
+                       if ( skb ) {
                                head_buffer = priv->rxBuffer + (priv->rxHead * TLAN_MAX_FRAME_SIZE);
                                skb_reserve(skb, 2);
-                               t = (void *) skb_put(skb, frameSize);
-
-                               dev->stats.rx_bytes += head_list->frameSize;
+                               pci_dma_sync_single_for_cpu(priv->pciDev,
+                                                           frameDma, frameSize,
+                                                           PCI_DMA_FROMDEVICE);
+                               skb_copy_from_linear_data(skb, head_buffer, frameSize);
+                               skb_put(skb, frameSize);
+                               dev->stats.rx_bytes += frameSize;
 
-                               memcpy( t, head_buffer, frameSize );
                                skb->protocol = eth_type_trans( skb, dev );
                                netif_rx( skb );
                        }
                } else {
                        struct sk_buff *new_skb;
 
-                       /*
-                        *      I changed the algorithm here. What we now do
-                        *      is allocate the new frame. If this fails we
-                        *      simply recycle the frame.
-                        */
-
-                       new_skb = dev_alloc_skb( TLAN_MAX_FRAME_SIZE + 7 );
-
-                       if ( new_skb != NULL ) {
+                       new_skb = netdev_alloc_skb(dev, TLAN_MAX_FRAME_SIZE + 7 );
+                       if ( new_skb ) {
                                skb = TLan_GetSKB(head_list);
-                               pci_unmap_single(priv->pciDev, head_list->buffer[0].address, TLAN_MAX_FRAME_SIZE, PCI_DMA_FROMDEVICE);
+                               pci_unmap_single(priv->pciDev, frameDma, TLAN_MAX_FRAME_SIZE, PCI_DMA_FROMDEVICE);
                                skb_put( skb, frameSize );
 
                                dev->stats.rx_bytes += frameSize;
@@ -1590,12 +1582,12 @@ static u32 TLan_HandleRxEOF( struct net_device *dev, u16 host_int )
                                skb->protocol = eth_type_trans( skb, dev );
                                netif_rx( skb );
 
-                               skb_reserve( new_skb, 2 );
+                               skb_reserve( new_skb, NET_IP_ALIGN );
                                head_list->buffer[0].address = pci_map_single(priv->pciDev, new_skb->data, TLAN_MAX_FRAME_SIZE, PCI_DMA_FROMDEVICE);
 
                                TLan_StoreSKB(head_list, new_skb);
-                       } else
-                               printk(KERN_WARNING "TLAN:  Couldn't allocate memory for received data.\n" );
+                       }
+
                }
 
                head_list->forward = 0;
@@ -1994,24 +1986,27 @@ static void TLan_ResetLists( struct net_device *dev )
                if ( bbuf ) {
                        list->buffer[0].address = priv->rxBufferDMA + ( i * TLAN_MAX_FRAME_SIZE );
                } else {
-                       skb = dev_alloc_skb( TLAN_MAX_FRAME_SIZE + 7 );
-                       if ( skb == NULL ) {
+                       skb = netdev_alloc_skb(dev, TLAN_MAX_FRAME_SIZE + 7 );
+                       if ( !skb ) {
                                printk( "TLAN:  Couldn't allocate memory for received data.\n" );
-                               /* If this ever happened it would be a problem */
-                       } else {
-                               skb->dev = dev;
-                               skb_reserve( skb, 2 );
+                               break;
                        }
+
+                       skb_reserve( skb, NET_IP_ALIGN );
                        list->buffer[0].address = pci_map_single(priv->pciDev, t, TLAN_MAX_FRAME_SIZE, PCI_DMA_FROMDEVICE);
                        TLan_StoreSKB(list, skb);
                }
                list->buffer[1].count = 0;
                list->buffer[1].address = 0;
-               if ( i < TLAN_NUM_RX_LISTS - 1 )
-                       list->forward = list_phys + sizeof(TLanList);
-               else
-                       list->forward = 0;
+               list->forward = list_phys + sizeof(TLanList);
+       }
+
+       /* in case ran out of memory early, clear bits */
+       while (i < TLAN_NUM_RX_LISTS) {
+               TLan_StoreSKB(priv->rxList + i, NULL);
+               ++i;
        }
+       list->forward = 0;
 
 } /* TLan_ResetLists */