sfc: Use DMA_BIT_MASK() instead of our own DMA mask macros

Also change type of efx_nic_type::max_dma_mask to u64, matching
pci_dma_supported() parameter type.
Signed-off-by: Ben Hutchings <bhutchings@solarflare.com>
Signed-off-by: Jeff Garzik <jgarzik@redhat.com>

drivers/net/sfc/bitfield.h

@@ -501,8 +501,5 @@ typedef union efx_oword {
 #define DMA_ADDR_T_WIDTH	(8 * sizeof(dma_addr_t))
 #define EFX_DMA_TYPE_WIDTH(width) \
 	(((width) < DMA_ADDR_T_WIDTH) ? (width) : DMA_ADDR_T_WIDTH)
-#define EFX_DMA_MAX_MASK ((DMA_ADDR_T_WIDTH == 64) ? \
-			  ~((u64) 0) : ~((u32) 0))
-#define EFX_DMA_MASK(mask) ((mask) & EFX_DMA_MAX_MASK)
 
 #endif /* EFX_BITFIELD_H */

drivers/net/sfc/falcon.c

@@ -116,17 +116,8 @@ MODULE_PARM_DESC(rx_xon_thresh_bytes, "RX fifo XON threshold");
  **************************************************************************
  */
 
-/* DMA address mask (up to 46-bit, avoiding compiler warnings)
- *
- * Note that it is possible to have a platform with 64-bit longs and
- * 32-bit DMA addresses, or vice versa.  EFX_DMA_MASK takes care of the
- * platform DMA mask.
- */
-#if BITS_PER_LONG == 64
-#define FALCON_DMA_MASK EFX_DMA_MASK(0x00003fffffffffffUL)
-#else
-#define FALCON_DMA_MASK EFX_DMA_MASK(0x00003fffffffffffULL)
-#endif
+/* DMA address mask */
+#define FALCON_DMA_MASK DMA_BIT_MASK(46)
 
 /* TX DMA length mask (13-bit) */
 #define FALCON_TX_DMA_MASK (4096 - 1)

drivers/net/sfc/net_driver.h

@@ -800,7 +800,7 @@ struct efx_nic_type {
 	unsigned int txd_ring_mask;
 	unsigned int rxd_ring_mask;
 	unsigned int evq_size;
-	dma_addr_t max_dma_mask;
+	u64 max_dma_mask;
 	unsigned int tx_dma_mask;
 	unsigned bug5391_mask;