amd-xgbe: Fix DMA API debug warning

When running a kernel configured with CONFIG_DMA_API_DEBUG=y a warning
is issued:
  DMA-API: device driver tries to sync DMA memory it has not allocated

This warning is the result of mapping the full range of the Rx buffer
pages allocated and then performing a dma_sync_single_for_cpu against
a calculated DMA address. The proper thing to do is to use the
dma_sync_single_range_for_cpu with a base DMA address and an offset.
Reported-by: Kim Phillips <kim.phillips@arm.com>
Signed-off-by: Tom Lendacky <thomas.lendacky@amd.com>
Tested-by: Kim Phillips <kim.phillips@arm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/net/ethernet/amd/xgbe/xgbe-desc.c

@@ -303,7 +303,8 @@ static void xgbe_set_buffer_data(struct xgbe_buffer_data *bd,
 	get_page(pa->pages);
 	bd->pa = *pa;
 
-	bd->dma = pa->pages_dma + pa->pages_offset;
+	bd->dma_base = pa->pages_dma;
+	bd->dma_off = pa->pages_offset;
 	bd->dma_len = len;
 
 	pa->pages_offset += len;

drivers/net/ethernet/amd/xgbe/xgbe-dev.c

@@ -1110,6 +1110,7 @@ static void xgbe_rx_desc_reset(struct xgbe_prv_data *pdata,
 	unsigned int rx_usecs = pdata->rx_usecs;
 	unsigned int rx_frames = pdata->rx_frames;
 	unsigned int inte;
+	dma_addr_t hdr_dma, buf_dma;
 
 	if (!rx_usecs && !rx_frames) {
 		/* No coalescing, interrupt for every descriptor */
@@ -1129,10 +1130,12 @@ static void xgbe_rx_desc_reset(struct xgbe_prv_data *pdata,
 	 *   Set buffer 2 (hi) address to buffer dma address (hi) and
 	 *     set control bits OWN and INTE
 	 */
-	rdesc->desc0 = cpu_to_le32(lower_32_bits(rdata->rx.hdr.dma));
-	rdesc->desc1 = cpu_to_le32(upper_32_bits(rdata->rx.hdr.dma));
-	rdesc->desc2 = cpu_to_le32(lower_32_bits(rdata->rx.buf.dma));
-	rdesc->desc3 = cpu_to_le32(upper_32_bits(rdata->rx.buf.dma));
+	hdr_dma = rdata->rx.hdr.dma_base + rdata->rx.hdr.dma_off;
+	buf_dma = rdata->rx.buf.dma_base + rdata->rx.buf.dma_off;
+	rdesc->desc0 = cpu_to_le32(lower_32_bits(hdr_dma));
+	rdesc->desc1 = cpu_to_le32(upper_32_bits(hdr_dma));
+	rdesc->desc2 = cpu_to_le32(lower_32_bits(buf_dma));
+	rdesc->desc3 = cpu_to_le32(upper_32_bits(buf_dma));
 
 	XGMAC_SET_BITS_LE(rdesc->desc3, RX_NORMAL_DESC3, INTE, inte);
 

drivers/net/ethernet/amd/xgbe/xgbe-drv.c

@@ -1765,7 +1765,8 @@ static struct sk_buff *xgbe_create_skb(struct xgbe_prv_data *pdata,
 	/* Start with the header buffer which may contain just the header
 	 * or the header plus data
 	 */
-	dma_sync_single_for_cpu(pdata->dev, rdata->rx.hdr.dma,
+	dma_sync_single_range_for_cpu(pdata->dev, rdata->rx.hdr.dma_base,
+				      rdata->rx.hdr.dma_off,
 				      rdata->rx.hdr.dma_len, DMA_FROM_DEVICE);
 
 	packet = page_address(rdata->rx.hdr.pa.pages) +
@@ -1778,8 +1779,11 @@ static struct sk_buff *xgbe_create_skb(struct xgbe_prv_data *pdata,
 	len -= copy_len;
 	if (len) {
 		/* Add the remaining data as a frag */
-		dma_sync_single_for_cpu(pdata->dev, rdata->rx.buf.dma,
-					rdata->rx.buf.dma_len, DMA_FROM_DEVICE);
+		dma_sync_single_range_for_cpu(pdata->dev,
+					      rdata->rx.buf.dma_base,
+					      rdata->rx.buf.dma_off,
+					      rdata->rx.buf.dma_len,
+					      DMA_FROM_DEVICE);
 
 		skb_add_rx_frag(skb, skb_shinfo(skb)->nr_frags,
 				rdata->rx.buf.pa.pages,
@@ -1945,8 +1949,9 @@ static int xgbe_rx_poll(struct xgbe_channel *channel, int budget)
 				if (!skb)
 					error = 1;
 			} else if (rdesc_len) {
-				dma_sync_single_for_cpu(pdata->dev,
-							rdata->rx.buf.dma,
+				dma_sync_single_range_for_cpu(pdata->dev,
+							rdata->rx.buf.dma_base,
+							rdata->rx.buf.dma_off,
 							rdata->rx.buf.dma_len,
 							DMA_FROM_DEVICE);
 

drivers/net/ethernet/amd/xgbe/xgbe.h

@@ -337,7 +337,8 @@ struct xgbe_buffer_data {
 	struct xgbe_page_alloc pa;
 	struct xgbe_page_alloc pa_unmap;
 
-	dma_addr_t dma;
+	dma_addr_t dma_base;
+	unsigned long dma_off;
 	unsigned int dma_len;
 };