From d8dd349eef3071993803d243721a9e657e476392 Mon Sep 17 00:00:00 2001
From: Keith Busch <keith.busch@intel.com>
Date: Tue, 6 Nov 2012 11:59:23 -0700
Subject: [PATCH] --- yaml --- r: 361683 b: refs/heads/master c:
 2b1960341576bf51c01b12fefeb1cc53820923e7 h: refs/heads/master i:   361681:
 5b375dfcfb0361ecbf7dbc3a55c7f7ae5258bdf9   361679:
 e0f0f1274efd77ffae27d09ba010a96280e93f51 v: v3

---
 [refs]                     | 2 +-
 trunk/drivers/block/nvme.c | 4 +++-
 2 files changed, 4 insertions(+), 2 deletions(-)

diff --git a/[refs] b/[refs]
index 11c453555569..a88f209aa00b 100644
--- a/[refs]
+++ b/[refs]
@@ -1,2 +1,2 @@
 ---
-refs/heads/master: 6ecec74520d8a357726e6c12f99080dbe7b347dd
+refs/heads/master: 2b1960341576bf51c01b12fefeb1cc53820923e7
diff --git a/trunk/drivers/block/nvme.c b/trunk/drivers/block/nvme.c
index 270805cf8d42..993c014d195a 100644
--- a/trunk/drivers/block/nvme.c
+++ b/trunk/drivers/block/nvme.c
@@ -337,6 +337,7 @@ nvme_alloc_iod(unsigned nseg, unsigned nbytes, gfp_t gfp)
 		iod->offset = offsetof(struct nvme_iod, sg[nseg]);
 		iod->npages = -1;
 		iod->length = nbytes;
+		iod->nents = 0;
 	}
 
 	return iod;
@@ -377,7 +378,8 @@ static void bio_completion(struct nvme_dev *dev, void *ctx,
 	struct bio *bio = iod->private;
 	u16 status = le16_to_cpup(&cqe->status) >> 1;
 
-	dma_unmap_sg(&dev->pci_dev->dev, iod->sg, iod->nents,
+	if (iod->nents)
+		dma_unmap_sg(&dev->pci_dev->dev, iod->sg, iod->nents,
 			bio_data_dir(bio) ? DMA_TO_DEVICE : DMA_FROM_DEVICE);
 	nvme_free_iod(dev, iod);
 	if (status) {