forcedeth: Fix WARNINGS that result when DMA mapping is not checked

With 3.8-rc1, the first call of pci_map_single() that is not checked
with a corresponding pci_dma_mapping_error() call results in a warning
with a splat as follows:

WARNING: at lib/dma-debug.c:933 check_unmap+0x480/0x950()
Hardware name: HP Pavilion dv2700 Notebook PC
forcedeth 0000:00:0a.0: DMA-API: device driver failed to check
 map error[device address=0x00000000b176e002] [size=90 bytes] [mapped as single]

Reviewed-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: Larry Finger <Larry.Finger@lwfinger.net>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/drivers/net/ethernet/nvidia/forcedeth.c b/drivers/net/ethernet/nvidia/forcedeth.c
index 653487dc7b52c58d69f42723cd5e572dfddc90a0..87fa5919c455224f8ee6ab47a4bae742e7fc801f 100644 (file)
--- a/drivers/net/ethernet/nvidia/forcedeth.c
+++ b/drivers/net/ethernet/nvidia/forcedeth.c
@@ -1821,6 +1821,11 @@ static int nv_alloc_rx(struct net_device *dev)
                                                             skb->data,
                                                             skb_tailroom(skb),
                                                             PCI_DMA_FROMDEVICE);
+                       if (pci_dma_mapping_error(np->pci_dev,
+                                                 np->put_rx_ctx->dma)) {
+                               kfree_skb(skb);
+                               goto packet_dropped;
+                       }
                        np->put_rx_ctx->dma_len = skb_tailroom(skb);
                        np->put_rx.orig->buf = cpu_to_le32(np->put_rx_ctx->dma);
                        wmb();
@@ -1830,6 +1835,7 @@ static int nv_alloc_rx(struct net_device *dev)
                        if (unlikely(np->put_rx_ctx++ == np->last_rx_ctx))
                                np->put_rx_ctx = np->first_rx_ctx;
                } else {
+packet_dropped:
                        u64_stats_update_begin(&np->swstats_rx_syncp);
                        np->stat_rx_dropped++;
                        u64_stats_update_end(&np->swstats_rx_syncp);
@@ -1856,6 +1862,11 @@ static int nv_alloc_rx_optimized(struct net_device *dev)
                                                             skb->data,
                                                             skb_tailroom(skb),
                                                             PCI_DMA_FROMDEVICE);
+                       if (pci_dma_mapping_error(np->pci_dev,
+                                                 np->put_rx_ctx->dma)) {
+                               kfree_skb(skb);
+                               goto packet_dropped;
+                       }
                        np->put_rx_ctx->dma_len = skb_tailroom(skb);
                        np->put_rx.ex->bufhigh = cpu_to_le32(dma_high(np->put_rx_ctx->dma));
                        np->put_rx.ex->buflow = cpu_to_le32(dma_low(np->put_rx_ctx->dma));
@@ -1866,6 +1877,7 @@ static int nv_alloc_rx_optimized(struct net_device *dev)
                        if (unlikely(np->put_rx_ctx++ == np->last_rx_ctx))
                                np->put_rx_ctx = np->first_rx_ctx;
                } else {
+packet_dropped:
                        u64_stats_update_begin(&np->swstats_rx_syncp);
                        np->stat_rx_dropped++;
                        u64_stats_update_end(&np->swstats_rx_syncp);
@@ -2217,6 +2229,15 @@ static netdev_tx_t nv_start_xmit(struct sk_buff *skb, struct net_device *dev)
                bcnt = (size > NV_TX2_TSO_MAX_SIZE) ? NV_TX2_TSO_MAX_SIZE : size;
                np->put_tx_ctx->dma = pci_map_single(np->pci_dev, skb->data + offset, bcnt,
                                                PCI_DMA_TODEVICE);
+               if (pci_dma_mapping_error(np->pci_dev,
+                                         np->put_tx_ctx->dma)) {
+                       /* on DMA mapping error - drop the packet */
+                       kfree_skb(skb);
+                       u64_stats_update_begin(&np->swstats_tx_syncp);
+                       np->stat_tx_dropped++;
+                       u64_stats_update_end(&np->swstats_tx_syncp);
+                       return NETDEV_TX_OK;
+               }
                np->put_tx_ctx->dma_len = bcnt;
                np->put_tx_ctx->dma_single = 1;
                put_tx->buf = cpu_to_le32(np->put_tx_ctx->dma);
@@ -2337,6 +2358,15 @@ static netdev_tx_t nv_start_xmit_optimized(struct sk_buff *skb,
                bcnt = (size > NV_TX2_TSO_MAX_SIZE) ? NV_TX2_TSO_MAX_SIZE : size;
                np->put_tx_ctx->dma = pci_map_single(np->pci_dev, skb->data + offset, bcnt,
                                                PCI_DMA_TODEVICE);
+               if (pci_dma_mapping_error(np->pci_dev,
+                                         np->put_tx_ctx->dma)) {
+                       /* on DMA mapping error - drop the packet */
+                       kfree_skb(skb);
+                       u64_stats_update_begin(&np->swstats_tx_syncp);
+                       np->stat_tx_dropped++;
+                       u64_stats_update_end(&np->swstats_tx_syncp);
+                       return NETDEV_TX_OK;
+               }
                np->put_tx_ctx->dma_len = bcnt;
                np->put_tx_ctx->dma_single = 1;
                put_tx->bufhigh = cpu_to_le32(dma_high(np->put_tx_ctx->dma));
@@ -5003,6 +5033,11 @@ static int nv_loopback_test(struct net_device *dev)
        test_dma_addr = pci_map_single(np->pci_dev, tx_skb->data,
                                       skb_tailroom(tx_skb),
                                       PCI_DMA_FROMDEVICE);
+       if (pci_dma_mapping_error(np->pci_dev,
+                                 test_dma_addr)) {
+               dev_kfree_skb_any(tx_skb);
+               goto out;
+       }
        pkt_data = skb_put(tx_skb, pkt_len);
        for (i = 0; i < pkt_len; i++)
                pkt_data[i] = (u8)(i & 0xff);