jme: Fix DMA unmap warning

The jme driver forgot to check the return status from pci_map_page in its tx
path, causing a dma api warning on unmap.  Easy fix, just do the check and
augment the tx path to tell the stack that the driver is busy so we re-queue the
frame.

Signed-off-by: Neil Horman <nhorman@tuxdriver.com>
CC: Guo-Fu Tseng <cooldavid@cooldavid.org>
CC: "David S. Miller" <davem@davemloft.net>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/drivers/net/ethernet/jme.c b/drivers/net/ethernet/jme.c
index b0c6050479eb460ae306cccaa93926f738e64c2e..6e664d9038d60df53b36b3869897cb49582fca16 100644 (file)
--- a/drivers/net/ethernet/jme.c
+++ b/drivers/net/ethernet/jme.c
@@ -1988,7 +1988,7 @@ jme_alloc_txdesc(struct jme_adapter *jme,
        return idx;
 }
 
-static void
+static int
 jme_fill_tx_map(struct pci_dev *pdev,
                struct txdesc *txdesc,
                struct jme_buffer_info *txbi,
@@ -2005,6 +2005,9 @@ jme_fill_tx_map(struct pci_dev *pdev,
                                len,
                                PCI_DMA_TODEVICE);
 
+       if (unlikely(pci_dma_mapping_error(pdev, dmaaddr)))
+               return -EINVAL;
+
        pci_dma_sync_single_for_device(pdev,
                                       dmaaddr,
                                       len,
@@ -2021,9 +2024,30 @@ jme_fill_tx_map(struct pci_dev *pdev,
 
        txbi->mapping = dmaaddr;
        txbi->len = len;
+       return 0;
 }
 
-static void
+static void jme_drop_tx_map(struct jme_adapter *jme, int startidx, int endidx)
+{
+       struct jme_ring *txring = &(jme->txring[0]);
+       struct jme_buffer_info *txbi = txring->bufinf, *ctxbi;
+       int mask = jme->tx_ring_mask;
+       int j;
+
+       for (j = startidx ; j < endidx ; ++j) {
+               ctxbi = txbi + ((startidx + j + 2) & (mask));
+               pci_unmap_page(jme->pdev,
+                               ctxbi->mapping,
+                               ctxbi->len,
+                               PCI_DMA_TODEVICE);
+
+                               ctxbi->mapping = 0;
+                               ctxbi->len = 0;
+       }
+
+}
+
+static int
 jme_map_tx_skb(struct jme_adapter *jme, struct sk_buff *skb, int idx)
 {
        struct jme_ring *txring = &(jme->txring[0]);
@@ -2034,25 +2058,37 @@ jme_map_tx_skb(struct jme_adapter *jme, struct sk_buff *skb, int idx)
        int mask = jme->tx_ring_mask;
        const struct skb_frag_struct *frag;
        u32 len;
+       int ret = 0;
 
        for (i = 0 ; i < nr_frags ; ++i) {
                frag = &skb_shinfo(skb)->frags[i];
                ctxdesc = txdesc + ((idx + i + 2) & (mask));
                ctxbi = txbi + ((idx + i + 2) & (mask));
 
-               jme_fill_tx_map(jme->pdev, ctxdesc, ctxbi,
+               ret = jme_fill_tx_map(jme->pdev, ctxdesc, ctxbi,
                                skb_frag_page(frag),
                                frag->page_offset, skb_frag_size(frag), hidma);
+               if (ret) {
+                       jme_drop_tx_map(jme, idx, idx+i);
+                       goto out;
+               }
+
        }
 
        len = skb_is_nonlinear(skb) ? skb_headlen(skb) : skb->len;
        ctxdesc = txdesc + ((idx + 1) & (mask));
        ctxbi = txbi + ((idx + 1) & (mask));
-       jme_fill_tx_map(jme->pdev, ctxdesc, ctxbi, virt_to_page(skb->data),
+       ret = jme_fill_tx_map(jme->pdev, ctxdesc, ctxbi, virt_to_page(skb->data),
                        offset_in_page(skb->data), len, hidma);
+       if (ret)
+               jme_drop_tx_map(jme, idx, idx+i);
+
+out:
+       return ret;
 
 }
 
+
 static int
 jme_tx_tso(struct sk_buff *skb, __le16 *mss, u8 *flags)
 {
@@ -2131,6 +2167,7 @@ jme_fill_tx_desc(struct jme_adapter *jme, struct sk_buff *skb, int idx)
        struct txdesc *txdesc;
        struct jme_buffer_info *txbi;
        u8 flags;
+       int ret = 0;
 
        txdesc = (struct txdesc *)txring->desc + idx;
        txbi = txring->bufinf + idx;
@@ -2155,7 +2192,10 @@ jme_fill_tx_desc(struct jme_adapter *jme, struct sk_buff *skb, int idx)
        if (jme_tx_tso(skb, &txdesc->desc1.mss, &flags))
                jme_tx_csum(jme, skb, &flags);
        jme_tx_vlan(skb, &txdesc->desc1.vlan, &flags);
-       jme_map_tx_skb(jme, skb, idx);
+       ret = jme_map_tx_skb(jme, skb, idx);
+       if (ret)
+               return ret;
+
        txdesc->desc1.flags = flags;
        /*
         * Set tx buffer info after telling NIC to send
@@ -2228,7 +2268,8 @@ jme_start_xmit(struct sk_buff *skb, struct net_device *netdev)
                return NETDEV_TX_BUSY;
        }
 
-       jme_fill_tx_desc(jme, skb, idx);
+       if (jme_fill_tx_desc(jme, skb, idx))
+               return NETDEV_TX_BUSY;
 
        jwrite32(jme, JME_TXCS, jme->reg_txcs |
                                TXCS_SELECT_QUEUE0 |