tg3: Generalize tg3_skb_error_unmap()

In the following patches, unmapping skb fragments will get just as
complicated as mapping them.  This patch generalizes
tg3_skb_error_unmap() and makes it the one-stop-shop for skb unmapping.

Signed-off-by: Matt Carlson <mcarlson@broadcom.com>
Reviewed-by: Michael Chan <mchan@broadcom.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
(cherry picked from commit 0d681b27b0efc962a3038a316e78373de7bfe1ce)

Signed-off-by: Joe Jin <joe.jin@oracle.com>

diff --git a/drivers/net/tg3.c b/drivers/net/tg3.c
index 20fcdbe714525680ef5ffeb976275a73b439aaa4..4db20cb0b02fb3c0b976d1abbca3998a9d1b077c 100644 (file)
--- a/drivers/net/tg3.c
+++ b/drivers/net/tg3.c
@@ -5919,13 +5919,15 @@ static inline void tg3_tx_set_bd(struct tg3_napi *tnapi, u32 entry,
        txbd->vlan_tag = (mss << TXD_MSS_SHIFT) | (vlan << TXD_VLAN_TAG_SHIFT);
 }
 
-static void tg3_skb_error_unmap(struct tg3_napi *tnapi,
-                               struct sk_buff *skb, int last)
+static void tg3_tx_skb_unmap(struct tg3_napi *tnapi, u32 entry, int last)
 {
        int i;
-       u32 entry = tnapi->tx_prod;
+       struct sk_buff *skb;
        struct tg3_tx_ring_info *txb = &tnapi->tx_buffers[entry];
 
+       skb = txb->skb;
+       txb->skb = NULL;
+
        pci_unmap_single(tnapi->tp->pdev,
                         dma_unmap_addr(txb, mapping),
                         skb_headlen(skb),
@@ -6233,7 +6235,7 @@ static netdev_tx_t tg3_start_xmit(struct sk_buff *skb, struct net_device *dev)
        }
 
        if (would_hit_hwbug) {
-               tg3_skb_error_unmap(tnapi, skb, i);
+               tg3_tx_skb_unmap(tnapi, tnapi->tx_prod, i);
 
                /* If the workaround fails due to memory/mapping
                 * failure, silently drop this packet.
@@ -6268,7 +6270,7 @@ out_unlock:
        return NETDEV_TX_OK;
 
 dma_error:
-       tg3_skb_error_unmap(tnapi, skb, i);
+       tg3_tx_skb_unmap(tnapi, tnapi->tx_prod, i);
        dev_kfree_skb(skb);
        tnapi->tx_buffers[tnapi->tx_prod].skb = NULL;
        return NETDEV_TX_OK;
@@ -6601,35 +6603,13 @@ static void tg3_free_rings(struct tg3 *tp)
                if (!tnapi->tx_buffers)
                        continue;
 
-               for (i = 0; i < TG3_TX_RING_SIZE; ) {
-                       struct tg3_tx_ring_info *txp;
-                       struct sk_buff *skb;
-                       unsigned int k;
+               for (i = 0; i < TG3_TX_RING_SIZE; i++) {
+                       struct sk_buff *skb = tnapi->tx_buffers[i].skb;
 
-                       txp = &tnapi->tx_buffers[i];
-                       skb = txp->skb;
-
-                       if (skb == NULL) {
-                               i++;
+                       if (!skb)
                                continue;
-                       }
 
-                       pci_unmap_single(tp->pdev,
-                                        dma_unmap_addr(txp, mapping),
-                                        skb_headlen(skb),
-                                        PCI_DMA_TODEVICE);
-                       txp->skb = NULL;
-
-                       i++;
-
-                       for (k = 0; k < skb_shinfo(skb)->nr_frags; k++) {
-                               txp = &tnapi->tx_buffers[i & (TG3_TX_RING_SIZE - 1)];
-                               pci_unmap_page(tp->pdev,
-                                              dma_unmap_addr(txp, mapping),
-                                              skb_shinfo(skb)->frags[k].size,
-                                              PCI_DMA_TODEVICE);
-                               i++;
-                       }
+                       tg3_tx_skb_unmap(tnapi, i, skb_shinfo(skb)->nr_frags);
 
                        dev_kfree_skb_any(skb);
                }
@@ -11326,6 +11306,10 @@ static int tg3_run_loopback(struct tg3 *tp, u32 pktsz, int loopback_mode)
                return -EIO;
        }
 
+       val = tnapi->tx_prod;
+       tnapi->tx_buffers[val].skb = skb;
+       dma_unmap_addr_set(&tnapi->tx_buffers[val], mapping, map);
+
        tw32_f(HOSTCC_MODE, tp->coalesce_mode | HOSTCC_MODE_ENABLE |
               rnapi->coal_now);
 
@@ -11357,7 +11341,7 @@ static int tg3_run_loopback(struct tg3 *tp, u32 pktsz, int loopback_mode)
                        break;
        }
 
-       pci_unmap_single(tp->pdev, map, tx_len, PCI_DMA_TODEVICE);
+       tg3_tx_skb_unmap(tnapi, tnapi->tx_prod - 1, 0);
        dev_kfree_skb(skb);
 
        if (tx_idx != tnapi->tx_prod)