Subject: [PATCH 1/4] ibmveth: Fix DMA unmap error

From: Anton Blanchard <[email-masked]>
Date: Thu, 08 Sep 2011 10:41:03 +1000

From: Brian King <[email-masked]>

Commit 6e8ab30ec677 (ibmveth: Add scatter-gather support) introduced a
DMA mapping API inconsistency resulting in dma_unmap_page getting
called on memory mapped via dma_map_single. This was seen when
CONFIG_DMA_API_DEBUG was enabled. Fix up this API usage inconsistency.

Signed-off-by: Brian King <[email-masked]>
Acked-by: Anton Blanchard <[email-masked]>
Cc: <[email-masked]> # v2.6.37+
---

Index: linux-build/drivers/net/ibmveth.c
===================================================================
--- linux-build.orig/drivers/net/ibmveth.c	2011-09-08 08:00:16.842856634 +1000
+++ linux-build/drivers/net/ibmveth.c	2011-09-08 09:45:43.163851274 +1000
@@ -1026,7 +1026,12 @@ retry_bounce:
 		netdev->stats.tx_bytes += skb->len;
 	}
 
-	for (i = 0; i < skb_shinfo(skb)->nr_frags + 1; i++)
+	dma_unmap_single(&adapter->vdev->dev,
+			 descs[0].fields.address,
+			 descs[0].fields.flags_len & IBMVETH_BUF_LEN_MASK,
+			 DMA_TO_DEVICE);
+
+	for (i = 1; i < skb_shinfo(skb)->nr_frags + 1; i++)
 		dma_unmap_page(&adapter->vdev->dev, descs[i].fields.address,
 			       descs[i].fields.flags_len & IBMVETH_BUF_LEN_MASK,
 			       DMA_TO_DEVICE);