From: Christoph Hellwig <hch@lst.de>
Date: Sun, 3 Mar 2019 15:52:21 +0000 (-0700)
Subject: nvme-pci: only call nvme_unmap_data for requests transferring data
X-Git-Url: http://git.lede-project.org./?a=commitdiff_plain;h=b15c592de37ed9d71499a3b8a750d1b235fcba3d;p=openwrt%2Fstaging%2Fblogic.git

nvme-pci: only call nvme_unmap_data for requests transferring data

This mirrors how nvme_map_pci is called and will allow simplifying some
checks in nvme_unmap_pci later on.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Keith Busch <keith.busch@intel.com>
Reviewed-by: Sagi Grimberg <sagi@grimberg.me>
Reviewed-by: Chaitanya Kulkarni <chaitanya.kulkarni@wdc.com>
---

diff --git a/drivers/nvme/host/pci.c b/drivers/nvme/host/pci.c
index de199aff8d05..030ee94452dd 100644
--- a/drivers/nvme/host/pci.c
+++ b/drivers/nvme/host/pci.c
@@ -929,7 +929,8 @@ static void nvme_pci_complete_rq(struct request *req)
 	struct nvme_iod *iod = blk_mq_rq_to_pdu(req);
 
 	nvme_cleanup_cmd(req);
-	nvme_unmap_data(iod->nvmeq->dev, req);
+	if (blk_rq_nr_phys_segments(req))
+		nvme_unmap_data(iod->nvmeq->dev, req);
 	nvme_complete_rq(req);
 }