s2io: Update driver to use dma_wmb

This change updates several spots where a wmb was being used to instead use
a dma_wmb to flush out writes before updating the control portion of the
descriptor.
Signed-off-by: NAlexander Duyck <alexander.h.duyck@redhat.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

drivers/net/ethernet/neterion/s2io.c

@@ -2520,7 +2520,7 @@ static int fill_rx_buffers(struct s2io_nic *nic, struct ring_info *ring,
 			DBG_PRINT(INFO_DBG, "%s: Could not allocate skb\n",
 				  ring->dev->name);
 			if (first_rxdp) {
-				wmb();
+				dma_wmb();
 				first_rxdp->Control_1 |= RXD_OWN_XENA;
 			}
 			swstats->mem_alloc_fail_cnt++;
@@ -2634,7 +2634,7 @@ static int fill_rx_buffers(struct s2io_nic *nic, struct ring_info *ring,
 		rxdp->Control_2 |= SET_RXD_MARKER;
 		if (!(alloc_tab & ((1 << rxsync_frequency) - 1))) {
 			if (first_rxdp) {
-				wmb();
+				dma_wmb();
 				first_rxdp->Control_1 |= RXD_OWN_XENA;
 			}
 			first_rxdp = rxdp;
@@ -2649,7 +2649,7 @@ static int fill_rx_buffers(struct s2io_nic *nic, struct ring_info *ring,
 	 * and other fields are seen by adapter correctly.
 	 */
 	if (first_rxdp) {
-		wmb();
+		dma_wmb();
 		first_rxdp->Control_1 |= RXD_OWN_XENA;
 	}
 
@@ -6950,7 +6950,7 @@ static  int rxd_owner_bit_reset(struct s2io_nic *sp)
 				}
 
 				set_rxd_buffer_size(sp, rxdp, size);
-				wmb();
+				dma_wmb();
 				/* flip the Ownership bit to Hardware */
 				rxdp->Control_1 |= RXD_OWN_XENA;
 			}