bnx2x: fix DMA API usage

With CONFIG_DMA_API_DEBUG=y bnx2x triggers the error "DMA-API: device
driver frees DMA memory with wrong function".
On archs where PAGE_SIZE > SGE_PAGE_SIZE it also triggers "DMA-API:
device driver frees DMA memory with different size".

Fix this by making the mapping and unmapping symmetric:
 - Do not map the whole pool page at once. Instead map the
   SGE_PAGE_SIZE-sized pieces individually, so they can be unmapped in
   the same manner.
 - What's mapped using dma_map_page() must be unmapped using
   dma_unmap_page().

Tested on ppc64.

Fixes: 4cace675d687 ("bnx2x: Alloc 4k fragment for each rx ring buffer element")
Signed-off-by: Michal Schmidt <mschmidt@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 2 insertions, 10 deletions

diff --git a/drivers/net/ethernet/broadcom/bnx2x/bnx2x_cmn.h b/drivers/net/ethernet/broadcom/bnx2x/bnx2x_cmn.h
index 2b30081ec26d..03b7404d5b9b 100644
--- a/drivers/net/ethernet/broadcom/bnx2x/bnx2x_cmn.h
+++ b/drivers/net/ethernet/broadcom/bnx2x/bnx2x_cmn.h
@@ -807,8 +807,8 @@ static inline void bnx2x_free_rx_sge(struct bnx2x *bp,
 	/* Since many fragments can share the same page, make sure to
 	 * only unmap and free the page once.
 	 */
-	dma_unmap_single(&bp->pdev->dev, dma_unmap_addr(sw_buf, mapping),
-			 SGE_PAGE_SIZE, DMA_FROM_DEVICE);
+	dma_unmap_page(&bp->pdev->dev, dma_unmap_addr(sw_buf, mapping),
+		       SGE_PAGE_SIZE, DMA_FROM_DEVICE);
 
 	put_page(page);
 
@@ -974,14 +974,6 @@ static inline void bnx2x_free_rx_mem_pool(struct bnx2x *bp,
 	if (!pool->page)
 		return;
 
-	/* Page was not fully fragmented.  Unmap unused space */
-	if (pool->offset < PAGE_SIZE) {
-		dma_addr_t dma = pool->dma + pool->offset;
-		int size = PAGE_SIZE - pool->offset;
-
-		dma_unmap_single(&bp->pdev->dev, dma, size, DMA_FROM_DEVICE);
-	}
-
 	put_page(pool->page);
 
 	pool->page = NULL;