Index: if_em.c
===================================================================
RCS file: /home/ncvs/src/sys/dev/em/if_em.c,v
retrieving revision 1.45
diff -u -p -r1.45 if_em.c
--- if_em.c	1 Sep 2004 23:22:41 -0000	1.45
+++ if_em.c	15 Sep 2004 17:45:08 -0000
@@ -1339,6 +1339,8 @@ em_encap(struct adapter *adapter, struct
          * Advance the Transmit Descriptor Tail (Tdt), this tells the E1000
          * that this frame is available to transmit.
          */
+        bus_dmamap_sync(adapter->txdma.dma_tag, adapter->txdma.dma_map,
+            BUS_DMASYNC_PREREAD | BUS_DMASYNC_PREWRITE);
         if (adapter->hw.mac_type == em_82547 &&
             adapter->link_duplex == HALF_DUPLEX) {
                 em_82547_move_tail_locked(adapter);
@@ -2400,6 +2402,8 @@ em_clean_transmit_interrupts(struct adap
         tx_buffer = &adapter->tx_buffer_area[i];
         tx_desc = &adapter->tx_desc_base[i];
 
+        bus_dmamap_sync(adapter->txdma.dma_tag, adapter->txdma.dma_map,
+            BUS_DMASYNC_POSTREAD);
         while (tx_desc->upper.fields.status & E1000_TXD_STAT_DD) {
 
                 tx_desc->upper.data = 0;
@@ -2407,8 +2411,6 @@ em_clean_transmit_interrupts(struct adap
 
                 if (tx_buffer->m_head) {
 			ifp->if_opackets++;
-                        bus_dmamap_sync(adapter->txtag, tx_buffer->map,
-                                        BUS_DMASYNC_POSTWRITE);
                         bus_dmamap_unload(adapter->txtag, tx_buffer->map);
                         bus_dmamap_destroy(adapter->txtag, tx_buffer->map);
 
@@ -2422,6 +2424,8 @@ em_clean_transmit_interrupts(struct adap
                 tx_buffer = &adapter->tx_buffer_area[i];
                 tx_desc = &adapter->tx_desc_base[i];
         }
+        bus_dmamap_sync(adapter->txdma.dma_tag, adapter->txdma.dma_map,
+            BUS_DMASYNC_PREREAD | BUS_DMASYNC_PREWRITE);
 
         adapter->oldest_used_tx_desc = i;
 
@@ -2561,6 +2565,8 @@ em_allocate_receive_structures(struct ad
                         return(error);
                 }
         }
+        bus_dmamap_sync(adapter->rxdma.dma_tag, adapter->rxdma.dma_map,
+            BUS_DMASYNC_PREREAD | BUS_DMASYNC_PREWRITE);
 
         return(0);
 
@@ -2746,6 +2752,8 @@ em_process_receive_interrupts(struct ada
 	ifp = &adapter->interface_data.ac_if;
 	i = adapter->next_rx_desc_to_check;
         current_desc = &adapter->rx_desc_base[i];
+	bus_dmamap_sync(adapter->rxdma.dma_tag, adapter->rxdma.dma_map,
+	    BUS_DMASYNC_POSTREAD | BUS_DMASYNC_POSTWRITE);
 
 	if (!((current_desc->status) & E1000_RXD_STAT_DD)) {
 #ifdef DBG_STATS
@@ -2893,6 +2901,8 @@ em_process_receive_interrupts(struct ada
                 } else
 			current_desc++;
 	}
+	bus_dmamap_sync(adapter->rxdma.dma_tag, adapter->rxdma.dma_map,
+	    BUS_DMASYNC_PREREAD | BUS_DMASYNC_PREWRITE);
 	adapter->next_rx_desc_to_check = i;
 	return;
 }