tg3: Consolidate code that calls tg3_tx_set_bd()

This patch consolidates all code that populates tx BDs into a single
routine.  Setting tx BDs needs to be more carefully controlled to see if
workarounds need to be applied.

Signed-off-by: Matt Carlson <mcarlson@broadcom.com>
Reviewed-by: Michael Chan <mchan@broadcom.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 42 insertions, 37 deletions

diff --git a/drivers/net/tg3.c b/drivers/net/tg3.c
index 90b68a229745..7f816a0ee421 100644
--- a/drivers/net/tg3.c
+++ b/drivers/net/tg3.c
@@ -5914,18 +5914,37 @@ static inline int tg3_40bit_overflow_test(struct tg3 *tp, dma_addr_t mapping,
 #endif
 }
 
-static inline void tg3_tx_set_bd(struct tg3_napi *tnapi, u32 entry,
+static inline void tg3_tx_set_bd(struct tg3_tx_buffer_desc *txbd,
                                  dma_addr_t mapping, u32 len, u32 flags,
                                  u32 mss, u32 vlan)
 {
-        struct tg3_tx_buffer_desc *txbd = &tnapi->tx_ring[entry];
-
         txbd->addr_hi = ((u64) mapping >> 32);
         txbd->addr_lo = ((u64) mapping & 0xffffffff);
         txbd->len_flags = (len << TXD_LEN_SHIFT) | (flags & 0x0000ffff);
         txbd->vlan_tag = (mss << TXD_MSS_SHIFT) | (vlan << TXD_VLAN_TAG_SHIFT);
 }
 
+static bool tg3_tx_frag_set(struct tg3_napi *tnapi, u32 entry,
+                            dma_addr_t map, u32 len, u32 flags,
+                            u32 mss, u32 vlan)
+{
+        struct tg3 *tp = tnapi->tp;
+        bool hwbug = false;
+
+        if (tg3_flag(tp, SHORT_DMA_BUG) && len <= 8)
+                hwbug = 1;
+
+        if (tg3_4g_overflow_test(map, len))
+                hwbug = 1;
+
+        if (tg3_40bit_overflow_test(tp, map, len))
+                hwbug = 1;
+
+        tg3_tx_set_bd(&tnapi->tx_ring[entry], map, len, flags, mss, vlan);
+
+        return hwbug;
+}
+
 static void tg3_tx_skb_unmap(struct tg3_napi *tnapi, u32 entry, int last)
 {
         int i;
@@ -5993,17 +6012,8 @@ static int tigon3_dma_hwbug_workaround(struct tg3_napi *tnapi,
                                           PCI_DMA_TODEVICE);
                 /* Make sure the mapping succeeded */
                 if (pci_dma_mapping_error(tp->pdev, new_addr)) {
-                        ret = -1;
                         dev_kfree_skb(new_skb);
-
-                /* Make sure new skb does not cross any 4G boundaries.
-                 * Drop the packet if it does.
-                 */
-                } else if (tg3_4g_overflow_test(new_addr, new_skb->len)) {
-                        pci_unmap_single(tp->pdev, new_addr, new_skb->len,
-                                         PCI_DMA_TODEVICE);
                         ret = -1;
-                        dev_kfree_skb(new_skb);
                 } else {
                         base_flags |= TXD_FLAG_END;
 
@@ -6011,8 +6021,13 @@ static int tigon3_dma_hwbug_workaround(struct tg3_napi *tnapi,
                         dma_unmap_addr_set(&tnapi->tx_buffers[entry],
                                            mapping, new_addr);
 
-                        tg3_tx_set_bd(tnapi, entry, new_addr, new_skb->len,
-                                      base_flags, mss, vlan);
+                        if (tg3_tx_frag_set(tnapi, entry, new_addr,
+                                            new_skb->len, base_flags,
+                                            mss, vlan)) {
+                                tg3_tx_skb_unmap(tnapi, entry, 0);
+                                dev_kfree_skb(new_skb);
+                                ret = -1;
+                        }
                 }
         }
 
@@ -6196,18 +6211,13 @@ static netdev_tx_t tg3_start_xmit(struct sk_buff *skb, struct net_device *dev)
 
         would_hit_hwbug = 0;
 
-        if (tg3_4g_overflow_test(mapping, len))
-                would_hit_hwbug = 1;
-
-        if (tg3_40bit_overflow_test(tp, mapping, len))
-                would_hit_hwbug = 1;
-
         if (tg3_flag(tp, 5701_DMA_BUG))
                 would_hit_hwbug = 1;
 
-        tg3_tx_set_bd(tnapi, entry, mapping, len, base_flags |
-                      ((skb_shinfo(skb)->nr_frags == 0) ? TXD_FLAG_END : 0),
-                      mss, vlan);
+        if (tg3_tx_frag_set(tnapi, entry, mapping, len, base_flags |
+                          ((skb_shinfo(skb)->nr_frags == 0) ? TXD_FLAG_END : 0),
+                            mss, vlan))
+                would_hit_hwbug = 1;
 
         entry = NEXT_TX(entry);
 
@@ -6236,20 +6246,11 @@ static netdev_tx_t tg3_start_xmit(struct sk_buff *skb, struct net_device *dev)
                         if (pci_dma_mapping_error(tp->pdev, mapping))
                                 goto dma_error;
 
-                        if (tg3_flag(tp, SHORT_DMA_BUG) &&
-                            len <= 8)
-                                would_hit_hwbug = 1;
-
-                        if (tg3_4g_overflow_test(mapping, len))
-                                would_hit_hwbug = 1;
-
-                        if (tg3_40bit_overflow_test(tp, mapping, len))
+                        if (tg3_tx_frag_set(tnapi, entry, mapping, len,
+                                  base_flags | ((i == last) ? TXD_FLAG_END : 0),
+                                            tmp_mss, vlan))
                                 would_hit_hwbug = 1;
 
-                        tg3_tx_set_bd(tnapi, entry, mapping, len, base_flags |
-                                      ((i == last) ? TXD_FLAG_END : 0),
-                                      tmp_mss, vlan);
-
                         entry = NEXT_TX(entry);
                 }
         }
@@ -11375,8 +11376,12 @@ static int tg3_run_loopback(struct tg3 *tp, u32 pktsz, int loopback_mode)
 
         rx_start_idx = rnapi->hw_status->idx[0].rx_producer;
 
-        tg3_tx_set_bd(tnapi, tnapi->tx_prod, map, tx_len,
-                      base_flags | TXD_FLAG_END, mss, 0);
+        if (tg3_tx_frag_set(tnapi, tnapi->tx_prod, map, tx_len,
+                            base_flags | TXD_FLAG_END, mss, 0)) {
+                tnapi->tx_buffers[val].skb = NULL;
+                dev_kfree_skb(skb);
+                return -EIO;
+        }
 
         tnapi->tx_prod++;