Francois Romieu <[EMAIL PROTECTED]> :
> Alistair John Strachan <[EMAIL PROTECTED]> :
> [...]
> > The "choke" affects other devices on the system too, notably libata, which 
> > does not recover gracefully. In my logs, I see a stream of:
> > 
> > DMA: Out of SW-IOMMU space for 7222 bytes at device 0000:04:00.0
> > DMA: Out of SW-IOMMU space for 7222 bytes at device 0000:04:00.0
> 
> You are using jumbo frames, aren't you ?

See below for my late night crap. At least it should avoid the driver
issuing Rx/Tx DMA with the single static buffer of lib/swiotlb.c
(io_tlb_overflow_buffer). Ghee.

diff --git a/drivers/net/r8169.c b/drivers/net/r8169.c
index 1f647b9..72a7370 100644
--- a/drivers/net/r8169.c
+++ b/drivers/net/r8169.c
@@ -2262,10 +2262,16 @@ static struct sk_buff *rtl8169_alloc_rx_skb(struct 
pci_dev *pdev,
        mapping = pci_map_single(pdev, skb->data, rx_buf_sz,
                                 PCI_DMA_FROMDEVICE);
 
+       if (pci_dma_mapping_error(mapping))
+               goto err_kfree_skb;
+
        rtl8169_map_to_asic(desc, mapping, rx_buf_sz);
 out:
        return skb;
 
+err_kfree_skb:
+       dev_kfree_skb(skb);
+       skb = NULL;
 err_out:
        rtl8169_make_unusable_by_asic(desc);
        goto out;
@@ -2486,6 +2492,7 @@ static int rtl8169_xmit_frags(struct rtl8169_private *tp, 
struct sk_buff *skb,
                dma_addr_t mapping;
                u32 status, len;
                void *addr;
+               int rc;
 
                entry = (entry + 1) % NUM_TX_DESC;
 
@@ -2493,6 +2500,22 @@ static int rtl8169_xmit_frags(struct rtl8169_private 
*tp, struct sk_buff *skb,
                len = frag->size;
                addr = ((void *) page_address(frag->page)) + frag->page_offset;
                mapping = pci_map_single(tp->pci_dev, addr, len, 
PCI_DMA_TODEVICE);
+               rc = pci_dma_mapping_error(mapping);
+               if (unlikely(rc < 0)) {
+                       while (cur_frag-- > 0) {
+                               frag = info->frags + cur_frag;
+                               entry = (entry - 1) % NUM_TX_DESC;
+                               txd = tp->TxDescArray + entry;
+                               len = frag->size;
+                               mapping = le64_to_cpu(txd->addr);
+                               pci_unmap_single(tp->pci_dev, mapping, len,
+                                                PCI_DMA_TODEVICE);
+                               txd->opts1 = 0x00;
+                               txd->opts2 = 0x00;
+                               txd->addr = 0x00;
+                       }
+                       return rc;
+               }
 
                /* anti gcc 2.95.3 bugware (sic) */
                status = opts1 | len | (RingEnd * !((entry + 1) % NUM_TX_DESC));
@@ -2534,13 +2557,13 @@ static inline u32 rtl8169_tso_csum(struct sk_buff *skb, 
struct net_device *dev)
 static int rtl8169_start_xmit(struct sk_buff *skb, struct net_device *dev)
 {
        struct rtl8169_private *tp = netdev_priv(dev);
-       unsigned int frags, entry = tp->cur_tx % NUM_TX_DESC;
+       unsigned int entry = tp->cur_tx % NUM_TX_DESC;
        struct TxDesc *txd = tp->TxDescArray + entry;
        void __iomem *ioaddr = tp->mmio_addr;
        dma_addr_t mapping;
        u32 status, len;
        u32 opts1;
-       int ret = NETDEV_TX_OK;
+       int frags, ret = NETDEV_TX_OK;
 
        if (unlikely(TX_BUFFS_AVAIL(tp) < skb_shinfo(skb)->nr_frags)) {
                if (netif_msg_drv(tp)) {
@@ -2557,7 +2580,11 @@ static int rtl8169_start_xmit(struct sk_buff *skb, 
struct net_device *dev)
        opts1 = DescOwn | rtl8169_tso_csum(skb, dev);
 
        frags = rtl8169_xmit_frags(tp, skb, opts1);
-       if (frags) {
+       if (frags < 0) {
+               printk(KERN_ERR "%s: PCI mapping failure (%d).\n", dev->name,
+                      frags);
+               goto err_busy;
+       } else if (frags > 0) {
                len = skb_headlen(skb);
                opts1 |= FirstFrag;
        } else {
@@ -2605,6 +2632,7 @@ out:
 
 err_stop:
        netif_stop_queue(dev);
+err_busy:
        ret = NETDEV_TX_BUSY;
 err_update_stats:
        dev->stats.tx_dropped++;
-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to [EMAIL PROTECTED]
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/

Reply via email to