netxen: handle dma mapping failures

o Bail out if pci_map_single() fails while replenishing rx ring.
o Drop packet if pci_map_{single,page}() fail in tx.

Signed-off-by: Dhananjay Phadke <dhananjay@netxen.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

3 files changed, 67 insertions, 40 deletions

diff --git a/drivers/net/netxen/netxen_nic.h b/drivers/net/netxen/netxen_nic.h
index 6598a34b87d4..c11c568fd7db 100644
--- a/drivers/net/netxen/netxen_nic.h
+++ b/drivers/net/netxen/netxen_nic.h
@@ -860,7 +860,6 @@ struct nx_host_rds_ring {
         u32 skb_size;
         struct netxen_rx_buffer *rx_buf_arr;    /* rx buffers for receive   */
         struct list_head free_list;
-        int begin_alloc;
 };
 
 /*
diff --git a/drivers/net/netxen/netxen_nic_init.c b/drivers/net/netxen/netxen_nic_init.c
index a3203644b482..ca7c8d8050c9 100644
--- a/drivers/net/netxen/netxen_nic_init.c
+++ b/drivers/net/netxen/netxen_nic_init.c
@@ -308,7 +308,6 @@ int netxen_alloc_sw_resources(struct netxen_adapter *adapter)
                         }
                         memset(rds_ring->rx_buf_arr, 0, RCV_BUFFSIZE);
                         INIT_LIST_HEAD(&rds_ring->free_list);
-                        rds_ring->begin_alloc = 0;
                         /*
                          * Now go through all of them, set reference handles
                          * and put them in the queues.
@@ -1435,7 +1434,6 @@ void netxen_post_rx_buffers(struct netxen_adapter *adapter, u32 ctx, u32 ringid)
         struct rcv_desc *pdesc;
         struct netxen_rx_buffer *buffer;
         int count = 0;
-        int index = 0;
         netxen_ctx_msg msg = 0;
         dma_addr_t dma;
         struct list_head *head;
@@ -1443,7 +1441,6 @@ void netxen_post_rx_buffers(struct netxen_adapter *adapter, u32 ctx, u32 ringid)
         rds_ring = &recv_ctx->rds_rings[ringid];
 
         producer = rds_ring->producer;
-        index = rds_ring->begin_alloc;
         head = &rds_ring->free_list;
 
         /* We can start writing rx descriptors into the phantom memory. */
@@ -1451,39 +1448,37 @@ void netxen_post_rx_buffers(struct netxen_adapter *adapter, u32 ctx, u32 ringid)
 
                 skb = dev_alloc_skb(rds_ring->skb_size);
                 if (unlikely(!skb)) {
-                        rds_ring->begin_alloc = index;
                         break;
                 }
 
+                if (!adapter->ahw.cut_through)
+                        skb_reserve(skb, 2);
+
+                dma = pci_map_single(pdev, skb->data,
+                                rds_ring->dma_size, PCI_DMA_FROMDEVICE);
+                if (pci_dma_mapping_error(pdev, dma)) {
+                        dev_kfree_skb_any(skb);
+                        break;
+                }
+
+                count++;
                 buffer = list_entry(head->next, struct netxen_rx_buffer, list);
                 list_del(&buffer->list);
 
-                count++;        /* now there should be no failure */
-                pdesc = &rds_ring->desc_head[producer];
-
-                if (!adapter->ahw.cut_through)
-                        skb_reserve(skb, 2);
-                /* This will be setup when we receive the
-                 * buffer after it has been filled  FSL  TBD TBD
-                 * skb->dev = netdev;
-                 */
-                dma = pci_map_single(pdev, skb->data, rds_ring->dma_size,
-                                     PCI_DMA_FROMDEVICE);
-                pdesc->addr_buffer = cpu_to_le64(dma);
                 buffer->skb = skb;
                 buffer->state = NETXEN_BUFFER_BUSY;
                 buffer->dma = dma;
+
                 /* make a rcv descriptor  */
+                pdesc = &rds_ring->desc_head[producer];
+                pdesc->addr_buffer = cpu_to_le64(dma);
                 pdesc->reference_handle = cpu_to_le16(buffer->ref_handle);
                 pdesc->buffer_length = cpu_to_le32(rds_ring->dma_size);
-                DPRINTK(INFO, "done writing descripter\n");
-                producer =
-                    get_next_index(producer, rds_ring->max_rx_desc_count);
-                index = get_next_index(index, rds_ring->max_rx_desc_count);
+
+                producer = get_next_index(producer, rds_ring->max_rx_desc_count);
         }
         /* if we did allocate buffers, then write the count to Phantom */
         if (count) {
-                rds_ring->begin_alloc = index;
                 rds_ring->producer = producer;
                         /* Window = 1 */
                 adapter->pci_write_normalize(adapter,
@@ -1522,49 +1517,50 @@ static void netxen_post_rx_buffers_nodb(struct netxen_adapter *adapter,
         struct rcv_desc *pdesc;
         struct netxen_rx_buffer *buffer;
         int count = 0;
-        int index = 0;
         struct list_head *head;
+        dma_addr_t dma;
 
         rds_ring = &recv_ctx->rds_rings[ringid];
 
         producer = rds_ring->producer;
-        index = rds_ring->begin_alloc;
         head = &rds_ring->free_list;
         /* We can start writing rx descriptors into the phantom memory. */
         while (!list_empty(head)) {
 
                 skb = dev_alloc_skb(rds_ring->skb_size);
                 if (unlikely(!skb)) {
-                        rds_ring->begin_alloc = index;
                         break;
                 }
 
+                if (!adapter->ahw.cut_through)
+                        skb_reserve(skb, 2);
+
+                dma = pci_map_single(pdev, skb->data,
+                                rds_ring->dma_size, PCI_DMA_FROMDEVICE);
+                if (pci_dma_mapping_error(pdev, dma)) {
+                        dev_kfree_skb_any(skb);
+                        break;
+                }
+
+                count++;
                 buffer = list_entry(head->next, struct netxen_rx_buffer, list);
                 list_del(&buffer->list);
 
-                count++;        /* now there should be no failure */
-                pdesc = &rds_ring->desc_head[producer];
-                if (!adapter->ahw.cut_through)
-                        skb_reserve(skb, 2);
                 buffer->skb = skb;
                 buffer->state = NETXEN_BUFFER_BUSY;
-                buffer->dma = pci_map_single(pdev, skb->data,
-                                             rds_ring->dma_size,
-                                             PCI_DMA_FROMDEVICE);
+                buffer->dma = dma;
 
                 /* make a rcv descriptor  */
+                pdesc = &rds_ring->desc_head[producer];
                 pdesc->reference_handle = cpu_to_le16(buffer->ref_handle);
                 pdesc->buffer_length = cpu_to_le32(rds_ring->dma_size);
                 pdesc->addr_buffer = cpu_to_le64(buffer->dma);
-                producer =
-                    get_next_index(producer, rds_ring->max_rx_desc_count);
-                index = get_next_index(index, rds_ring->max_rx_desc_count);
-                buffer = &rds_ring->rx_buf_arr[index];
+
+                producer = get_next_index(producer, rds_ring->max_rx_desc_count);
         }
 
         /* if we did allocate buffers, then write the count to Phantom */
         if (count) {
-                rds_ring->begin_alloc = index;
                 rds_ring->producer = producer;
                         /* Window = 1 */
                 adapter->pci_write_normalize(adapter,
diff --git a/drivers/net/netxen/netxen_nic_main.c b/drivers/net/netxen/netxen_nic_main.c
index 9268fd2fbacf..86867405a367 100644
--- a/drivers/net/netxen/netxen_nic_main.c
+++ b/drivers/net/netxen/netxen_nic_main.c
@@ -1200,6 +1200,24 @@ static bool netxen_tso_check(struct net_device *netdev,
         return tso;
 }
 
+static void
+netxen_clean_tx_dma_mapping(struct pci_dev *pdev,
+                struct netxen_cmd_buffer *pbuf, int last)
+{
+        int k;
+        struct netxen_skb_frag *buffrag;
+
+        buffrag = &pbuf->frag_array[0];
+        pci_unmap_single(pdev, buffrag->dma,
+                        buffrag->length, PCI_DMA_TODEVICE);
+
+        for (k = 1; k < last; k++) {
+                buffrag = &pbuf->frag_array[k];
+                pci_unmap_page(pdev, buffrag->dma,
+                        buffrag->length, PCI_DMA_TODEVICE);
+        }
+}
+
 static int netxen_nic_xmit_frame(struct sk_buff *skb, struct net_device *netdev)
 {
         struct netxen_adapter *adapter = netdev_priv(netdev);
@@ -1208,6 +1226,8 @@ static int netxen_nic_xmit_frame(struct sk_buff *skb, struct net_device *netdev)
         struct netxen_cmd_buffer *pbuf;
         struct netxen_skb_frag *buffrag;
         struct cmd_desc_type0 *hwdesc;
+        struct pci_dev *pdev = adapter->pdev;
+        dma_addr_t temp_dma;
         int i, k;
 
         u32 producer, consumer;
@@ -1240,8 +1260,12 @@ static int netxen_nic_xmit_frame(struct sk_buff *skb, struct net_device *netdev)
         pbuf->skb = skb;
         pbuf->frag_count = frag_count;
         buffrag = &pbuf->frag_array[0];
-        buffrag->dma = pci_map_single(adapter->pdev, skb->data, first_seg_len,
+        temp_dma = pci_map_single(pdev, skb->data, first_seg_len,
                                       PCI_DMA_TODEVICE);
+        if (pci_dma_mapping_error(pdev, temp_dma))
+                goto drop_packet;
+
+        buffrag->dma = temp_dma;
         buffrag->length = first_seg_len;
         netxen_set_tx_frags_len(hwdesc, frag_count, skb->len);
         netxen_set_tx_port(hwdesc, adapter->portnum);
@@ -1253,7 +1277,6 @@ static int netxen_nic_xmit_frame(struct sk_buff *skb, struct net_device *netdev)
                 struct skb_frag_struct *frag;
                 int len, temp_len;
                 unsigned long offset;
-                dma_addr_t temp_dma;
 
                 /* move to next desc. if there is a need */
                 if ((i & 0x3) == 0) {
@@ -1269,8 +1292,12 @@ static int netxen_nic_xmit_frame(struct sk_buff *skb, struct net_device *netdev)
                 offset = frag->page_offset;
 
                 temp_len = len;
-                temp_dma = pci_map_page(adapter->pdev, frag->page, offset,
+                temp_dma = pci_map_page(pdev, frag->page, offset,
                                         len, PCI_DMA_TODEVICE);
+                if (pci_dma_mapping_error(pdev, temp_dma)) {
+                        netxen_clean_tx_dma_mapping(pdev, pbuf, i);
+                        goto drop_packet;
+                }
 
                 buffrag++;
                 buffrag->dma = temp_dma;
@@ -1345,6 +1372,11 @@ static int netxen_nic_xmit_frame(struct sk_buff *skb, struct net_device *netdev)
         netdev->trans_start = jiffies;
 
         return NETDEV_TX_OK;
+
+drop_packet:
+        adapter->stats.txdropped++;
+        dev_kfree_skb_any(skb);
+        return NETDEV_TX_OK;
 }
 
 static int netxen_nic_check_temp(struct netxen_adapter *adapter)