tg3: Cleanup transmit error path
This patch consolidates the skb cleanup code into a function named
tg3_skb_error_unmap(). The modification addresses a long-standing bug
where pci_unmap_single() was incorrectly being called instead of
pci_unmap_page() in tigon3_dma_hwbug_workaround().
Signed-off-by: Matt Carlson <mcarlson@broadcom.com>
Reviewed-by: Michael Chan <mchan@broadcom.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/drivers/net/tg3.c b/drivers/net/tg3.c
index 4c44168..b2b1ba1 100644
--- a/drivers/net/tg3.c
+++ b/drivers/net/tg3.c
@@ -5758,16 +5758,39 @@
txd->vlan_tag = vlan_tag << TXD_VLAN_TAG_SHIFT;
}
+static void tg3_skb_error_unmap(struct tg3_napi *tnapi,
+ struct sk_buff *skb, int last)
+{
+ int i;
+ u32 entry = tnapi->tx_prod;
+ struct ring_info *txb = &tnapi->tx_buffers[entry];
+
+ pci_unmap_single(tnapi->tp->pdev,
+ dma_unmap_addr(txb, mapping),
+ skb_headlen(skb),
+ PCI_DMA_TODEVICE);
+ for (i = 0; i <= last; i++) {
+ skb_frag_t *frag = &skb_shinfo(skb)->frags[i];
+
+ entry = NEXT_TX(entry);
+ txb = &tnapi->tx_buffers[entry];
+
+ pci_unmap_page(tnapi->tp->pdev,
+ dma_unmap_addr(txb, mapping),
+ frag->size, PCI_DMA_TODEVICE);
+ }
+}
+
/* Workaround 4GB and 40-bit hardware DMA bugs. */
static int tigon3_dma_hwbug_workaround(struct tg3_napi *tnapi,
- struct sk_buff *skb, u32 last_plus_one,
- u32 *start, u32 base_flags, u32 mss)
+ struct sk_buff *skb,
+ u32 base_flags, u32 mss)
{
struct tg3 *tp = tnapi->tp;
struct sk_buff *new_skb;
dma_addr_t new_addr = 0;
- u32 entry = *start;
- int i, ret = 0;
+ u32 entry = tnapi->tx_prod;
+ int ret = 0;
if (GET_ASIC_REV(tp->pci_chip_rev_id) != ASIC_REV_5701)
new_skb = skb_copy(skb, GFP_ATOMIC);
@@ -5783,14 +5806,12 @@
ret = -1;
} else {
/* New SKB is guaranteed to be linear. */
- entry = *start;
new_addr = pci_map_single(tp->pdev, new_skb->data, new_skb->len,
PCI_DMA_TODEVICE);
/* Make sure the mapping succeeded */
if (pci_dma_mapping_error(tp->pdev, new_addr)) {
ret = -1;
dev_kfree_skb(new_skb);
- new_skb = NULL;
/* Make sure new skb does not cross any 4G boundaries.
* Drop the packet if it does.
@@ -5801,39 +5822,16 @@
PCI_DMA_TODEVICE);
ret = -1;
dev_kfree_skb(new_skb);
- new_skb = NULL;
} else {
+ tnapi->tx_buffers[entry].skb = new_skb;
+ dma_unmap_addr_set(&tnapi->tx_buffers[entry],
+ mapping, new_addr);
+
tg3_set_txd(tnapi, entry, new_addr, new_skb->len,
base_flags, 1 | (mss << 1));
- *start = NEXT_TX(entry);
}
}
- /* Now clean up the sw ring entries. */
- i = 0;
- while (entry != last_plus_one) {
- int len;
-
- if (i == 0)
- len = skb_headlen(skb);
- else
- len = skb_shinfo(skb)->frags[i-1].size;
-
- pci_unmap_single(tp->pdev,
- dma_unmap_addr(&tnapi->tx_buffers[entry],
- mapping),
- len, PCI_DMA_TODEVICE);
- if (i == 0) {
- tnapi->tx_buffers[entry].skb = new_skb;
- dma_unmap_addr_set(&tnapi->tx_buffers[entry], mapping,
- new_addr);
- } else {
- tnapi->tx_buffers[entry].skb = NULL;
- }
- entry = NEXT_TX(entry);
- i++;
- }
-
dev_kfree_skb(skb);
return ret;
@@ -5889,11 +5887,11 @@
{
struct tg3 *tp = netdev_priv(dev);
u32 len, entry, base_flags, mss;
- int would_hit_hwbug;
+ int i = -1, would_hit_hwbug;
dma_addr_t mapping;
struct tg3_napi *tnapi;
struct netdev_queue *txq;
- unsigned int i, last;
+ unsigned int last;
txq = netdev_get_tx_queue(dev, skb_get_queue_mapping(skb));
tnapi = &tp->napi[skb_get_queue_mapping(skb)];
@@ -6074,20 +6072,15 @@
}
if (would_hit_hwbug) {
- u32 last_plus_one = entry;
- u32 start;
-
- start = entry - 1 - skb_shinfo(skb)->nr_frags;
- start &= (TG3_TX_RING_SIZE - 1);
+ tg3_skb_error_unmap(tnapi, skb, i);
/* If the workaround fails due to memory/mapping
* failure, silently drop this packet.
*/
- if (tigon3_dma_hwbug_workaround(tnapi, skb, last_plus_one,
- &start, base_flags, mss))
+ if (tigon3_dma_hwbug_workaround(tnapi, skb, base_flags, mss))
goto out_unlock;
- entry = start;
+ entry = NEXT_TX(tnapi->tx_prod);
}
/* Packets are ready, update Tx producer idx local and on card. */
@@ -6113,24 +6106,9 @@
return NETDEV_TX_OK;
dma_error:
- last = i;
- entry = tnapi->tx_prod;
- tnapi->tx_buffers[entry].skb = NULL;
- pci_unmap_single(tp->pdev,
- dma_unmap_addr(&tnapi->tx_buffers[entry], mapping),
- skb_headlen(skb),
- PCI_DMA_TODEVICE);
- for (i = 0; i <= last; i++) {
- skb_frag_t *frag = &skb_shinfo(skb)->frags[i];
- entry = NEXT_TX(entry);
-
- pci_unmap_page(tp->pdev,
- dma_unmap_addr(&tnapi->tx_buffers[entry],
- mapping),
- frag->size, PCI_DMA_TODEVICE);
- }
-
+ tg3_skb_error_unmap(tnapi, skb, i);
dev_kfree_skb(skb);
+ tnapi->tx_buffers[tnapi->tx_prod].skb = NULL;
return NETDEV_TX_OK;
}