gve: DQO: avoid unused variable warnings

The use of dma_unmap_addr()/dma_unmap_len() in the driver causes
multiple warnings when these macros are defined as empty, e.g.
in an ARCH=i386 allmodconfig build:

drivers/net/ethernet/google/gve/gve_tx_dqo.c: In function 'gve_tx_add_skb_no_copy_dqo':
drivers/net/ethernet/google/gve/gve_tx_dqo.c:494:40: error: unused variable 'buf' [-Werror=unused-variable]
  494 |                 struct gve_tx_dma_buf *buf =

This is not how the NEED_DMA_MAP_STATE macros are meant to work,
as they rely on never using local variables or a temporary structure
like gve_tx_dma_buf.

Remote the gve_tx_dma_buf definition and open-code the contents
in all places to avoid the warning. This causes some rather long
lines but otherwise ends up making the driver slightly smaller.

Fixes: a57e5de476be ("gve: DQO: Add TX path")
Link: https://lore.kernel.org/netdev/20210723231957.1113800-1-bcf@google.com/
Link: https://lore.kernel.org/netdev/20210721151100.2042139-1-arnd@kernel.org/
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 10 insertions, 13 deletions

diff --git a/drivers/net/ethernet/google/gve/gve_tx.c b/drivers/net/ethernet/google/gve/gve_tx.c
index 665ac795a1ad..9922ce46a635 100644
--- a/drivers/net/ethernet/google/gve/gve_tx.c
+++ b/drivers/net/ethernet/google/gve/gve_tx.c
@@ -303,15 +303,15 @@ static inline int gve_skb_fifo_bytes_required(struct gve_tx_ring *tx,
 static void gve_tx_unmap_buf(struct device *dev, struct gve_tx_buffer_state *info)
 {
 	if (info->skb) {
-		dma_unmap_single(dev, dma_unmap_addr(&info->buf, dma),
-				 dma_unmap_len(&info->buf, len),
+		dma_unmap_single(dev, dma_unmap_addr(info, dma),
+				 dma_unmap_len(info, len),
 				 DMA_TO_DEVICE);
-		dma_unmap_len_set(&info->buf, len, 0);
+		dma_unmap_len_set(info, len, 0);
 	} else {
-		dma_unmap_page(dev, dma_unmap_addr(&info->buf, dma),
-			       dma_unmap_len(&info->buf, len),
+		dma_unmap_page(dev, dma_unmap_addr(info, dma),
+			       dma_unmap_len(info, len),
 			       DMA_TO_DEVICE);
-		dma_unmap_len_set(&info->buf, len, 0);
+		dma_unmap_len_set(info, len, 0);
 	}
 }
 
@@ -491,7 +491,6 @@ static int gve_tx_add_skb_no_copy(struct gve_priv *priv, struct gve_tx_ring *tx,
 	struct gve_tx_buffer_state *info;
 	bool is_gso = skb_is_gso(skb);
 	u32 idx = tx->req & tx->mask;
-	struct gve_tx_dma_buf *buf;
 	u64 addr;
 	u32 len;
 	int i;
@@ -515,9 +514,8 @@ static int gve_tx_add_skb_no_copy(struct gve_priv *priv, struct gve_tx_ring *tx,
 		tx->dma_mapping_error++;
 		goto drop;
 	}
-	buf = &info->buf;
-	dma_unmap_len_set(buf, len, len);
-	dma_unmap_addr_set(buf, dma, addr);
+	dma_unmap_len_set(info, len, len);
+	dma_unmap_addr_set(info, dma, addr);
 
 	payload_nfrags = shinfo->nr_frags;
 	if (hlen < len) {
@@ -549,10 +547,9 @@ static int gve_tx_add_skb_no_copy(struct gve_priv *priv, struct gve_tx_ring *tx,
 			tx->dma_mapping_error++;
 			goto unmap_drop;
 		}
-		buf = &tx->info[idx].buf;
 		tx->info[idx].skb = NULL;
-		dma_unmap_len_set(buf, len, len);
-		dma_unmap_addr_set(buf, dma, addr);
+		dma_unmap_len_set(&tx->info[idx], len, len);
+		dma_unmap_addr_set(&tx->info[idx], dma, addr);
 
 		gve_tx_fill_seg_desc(seg_desc, skb, is_gso, len, addr);
 	}