myri10ge: check for DMA mapping errors

On IOMMU systems DMA mapping can fail, we need to check for
that possibility.

Signed-off-by: Stanislaw Gruszka <sgruszka@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/drivers/net/ethernet/myricom/myri10ge/myri10ge.c b/drivers/net/ethernet/myricom/myri10ge/myri10ge.c
index 69c26f0..679db02 100644 (file)
--- a/drivers/net/ethernet/myricom/myri10ge/myri10ge.c
+++ b/drivers/net/ethernet/myricom/myri10ge/myri10ge.c
@@ -873,6 +873,10 @@ static int myri10ge_dma_test(struct myri10ge_priv *mgp, int test_type)
                return -ENOMEM;
        dmatest_bus = pci_map_page(mgp->pdev, dmatest_page, 0, PAGE_SIZE,
                                   DMA_BIDIRECTIONAL);
+       if (unlikely(pci_dma_mapping_error(mgp->pdev, dmatest_bus))) {
+               __free_page(dmatest_page);
+               return -ENOMEM;
+       }
 
        /* Run a small DMA test.
         * The magic multipliers to the length tell the firmware
@@ -1294,6 +1298,7 @@ myri10ge_alloc_rx_pages(struct myri10ge_priv *mgp, struct myri10ge_rx_buf *rx,
                        int bytes, int watchdog)
 {
        struct page *page;
+       dma_addr_t bus;
        int idx;
 #if MYRI10GE_ALLOC_SIZE > 4096
        int end_offset;
@@ -1318,11 +1323,21 @@ myri10ge_alloc_rx_pages(struct myri10ge_priv *mgp, struct myri10ge_rx_buf *rx,
                                        rx->watchdog_needed = 1;
                                return;
                        }
+
+                       bus = pci_map_page(mgp->pdev, page, 0,
+                                          MYRI10GE_ALLOC_SIZE,
+                                          PCI_DMA_FROMDEVICE);
+                       if (unlikely(pci_dma_mapping_error(mgp->pdev, bus))) {
+                               __free_pages(page, MYRI10GE_ALLOC_ORDER);
+                               if (rx->fill_cnt - rx->cnt < 16)
+                                       rx->watchdog_needed = 1;
+                               return;
+                       }
+
                        rx->page = page;
                        rx->page_offset = 0;
-                       rx->bus = pci_map_page(mgp->pdev, page, 0,
-                                              MYRI10GE_ALLOC_SIZE,
-                                              PCI_DMA_FROMDEVICE);
+                       rx->bus = bus;
+
                }
                rx->info[idx].page = rx->page;
                rx->info[idx].page_offset = rx->page_offset;
@@ -2764,6 +2779,35 @@ myri10ge_submit_req(struct myri10ge_tx_buf *tx, struct mcp_kreq_ether_send *src,
        mb();
 }
 
+static void myri10ge_unmap_tx_dma(struct myri10ge_priv *mgp,
+                                 struct myri10ge_tx_buf *tx, int idx)
+{
+       unsigned int len;
+       int last_idx;
+
+       /* Free any DMA resources we've alloced and clear out the skb slot */
+       last_idx = (idx + 1) & tx->mask;
+       idx = tx->req & tx->mask;
+       do {
+               len = dma_unmap_len(&tx->info[idx], len);
+               if (len) {
+                       if (tx->info[idx].skb != NULL)
+                               pci_unmap_single(mgp->pdev,
+                                                dma_unmap_addr(&tx->info[idx],
+                                                               bus), len,
+                                                PCI_DMA_TODEVICE);
+                       else
+                               pci_unmap_page(mgp->pdev,
+                                              dma_unmap_addr(&tx->info[idx],
+                                                             bus), len,
+                                              PCI_DMA_TODEVICE);
+                       dma_unmap_len_set(&tx->info[idx], len, 0);
+                       tx->info[idx].skb = NULL;
+               }
+               idx = (idx + 1) & tx->mask;
+       } while (idx != last_idx);
+}
+
 /*
  * Transmit a packet.  We need to split the packet so that a single
  * segment does not cross myri10ge->tx_boundary, so this makes segment
@@ -2787,7 +2831,7 @@ static netdev_tx_t myri10ge_xmit(struct sk_buff *skb,
        u32 low;
        __be32 high_swapped;
        unsigned int len;
-       int idx, last_idx, avail, frag_cnt, frag_idx, count, mss, max_segments;
+       int idx, avail, frag_cnt, frag_idx, count, mss, max_segments;
        u16 pseudo_hdr_offset, cksum_offset, queue;
        int cum_len, seglen, boundary, rdma_count;
        u8 flags, odd_flag;
@@ -2884,9 +2928,12 @@ again:
 
        /* map the skb for DMA */
        len = skb_headlen(skb);
+       bus = pci_map_single(mgp->pdev, skb->data, len, PCI_DMA_TODEVICE);
+       if (unlikely(pci_dma_mapping_error(mgp->pdev, bus)))
+               goto drop;
+
        idx = tx->req & tx->mask;
        tx->info[idx].skb = skb;
-       bus = pci_map_single(mgp->pdev, skb->data, len, PCI_DMA_TODEVICE);
        dma_unmap_addr_set(&tx->info[idx], bus, bus);
        dma_unmap_len_set(&tx->info[idx], len, len);
 
@@ -2985,12 +3032,16 @@ again:
                        break;
 
                /* map next fragment for DMA */
-               idx = (count + tx->req) & tx->mask;
                frag = &skb_shinfo(skb)->frags[frag_idx];
                frag_idx++;
                len = skb_frag_size(frag);
                bus = skb_frag_dma_map(&mgp->pdev->dev, frag, 0, len,
                                       DMA_TO_DEVICE);
+               if (unlikely(pci_dma_mapping_error(mgp->pdev, bus))) {
+                       myri10ge_unmap_tx_dma(mgp, tx, idx);
+                       goto drop;
+               }
+               idx = (count + tx->req) & tx->mask;
                dma_unmap_addr_set(&tx->info[idx], bus, bus);
                dma_unmap_len_set(&tx->info[idx], len, len);
        }
@@ -3021,31 +3072,8 @@ again:
        return NETDEV_TX_OK;
 
 abort_linearize:
-       /* Free any DMA resources we've alloced and clear out the skb
-        * slot so as to not trip up assertions, and to avoid a
-        * double-free if linearizing fails */
+       myri10ge_unmap_tx_dma(mgp, tx, idx);
 
-       last_idx = (idx + 1) & tx->mask;
-       idx = tx->req & tx->mask;
-       tx->info[idx].skb = NULL;
-       do {
-               len = dma_unmap_len(&tx->info[idx], len);
-               if (len) {
-                       if (tx->info[idx].skb != NULL)
-                               pci_unmap_single(mgp->pdev,
-                                                dma_unmap_addr(&tx->info[idx],
-                                                               bus), len,
-                                                PCI_DMA_TODEVICE);
-                       else
-                               pci_unmap_page(mgp->pdev,
-                                              dma_unmap_addr(&tx->info[idx],
-                                                             bus), len,
-                                              PCI_DMA_TODEVICE);
-                       dma_unmap_len_set(&tx->info[idx], len, 0);
-                       tx->info[idx].skb = NULL;
-               }
-               idx = (idx + 1) & tx->mask;
-       } while (idx != last_idx);
        if (skb_is_gso(skb)) {
                netdev_err(mgp->dev, "TSO but wanted to linearize?!?!?\n");
                goto drop;