[PATCH v3 2/3] nvme: implement DMA_ATTR_NO_WARN

From: Mauricio Faria de Oliveira
Date: Fri Jul 08 2016 - 08:27:55 EST


Use the DMA_ATTR_NO_WARN attribute on dma_map_sg() calls of nvme driver.

Signed-off-by: Mauricio Faria de Oliveira <mauricfo@xxxxxxxxxxxxxxxxxx>
Reviewed-by: Gabriel Krisman Bertazi <krisman@xxxxxxxxxxxxxxxxxx>
---
Changelog:
v3:
- nvme: use DMA_ATTR_NO_WARN when ret = BLK_MQ_RQ_QUEUE_BUSY (io will be
requeued) but not when ret = BLK_MQ_RQ_QUEUE_ERROR (io will be failed).
thanks: Masayoshi Mizuma <m.mizuma@xxxxxxxxxxxxxx>
v2:
- all: address warnings from checkpatch.pl (line wrapping and typos)

drivers/nvme/host/pci.c | 9 ++++++++-
1 file changed, 8 insertions(+), 1 deletion(-)

diff --git a/drivers/nvme/host/pci.c b/drivers/nvme/host/pci.c
index d1a8259..187aa6b 100644
--- a/drivers/nvme/host/pci.c
+++ b/drivers/nvme/host/pci.c
@@ -18,6 +18,7 @@
#include <linux/blk-mq.h>
#include <linux/cpu.h>
#include <linux/delay.h>
+#include <linux/dma-attrs.h>
#include <linux/errno.h>
#include <linux/fs.h>
#include <linux/genhd.h>
@@ -65,6 +66,8 @@ MODULE_PARM_DESC(use_cmb_sqes, "use controller's memory buffer for I/O SQes");

static struct workqueue_struct *nvme_workq;

+static DEFINE_DMA_ATTRS(nvme_dma_attrs);
+
struct nvme_dev;
struct nvme_queue;

@@ -498,7 +501,8 @@ static int nvme_map_data(struct nvme_dev *dev, struct request *req,
goto out;

ret = BLK_MQ_RQ_QUEUE_BUSY;
- if (!dma_map_sg(dev->dev, iod->sg, iod->nents, dma_dir))
+ if (!dma_map_sg_attrs(dev->dev, iod->sg, iod->nents, dma_dir,
+ &nvme_dma_attrs))
goto out;

if (!nvme_setup_prps(dev, req, size))
@@ -2118,6 +2122,9 @@ static int __init nvme_init(void)
result = pci_register_driver(&nvme_driver);
if (result)
destroy_workqueue(nvme_workq);
+
+ dma_set_attr(DMA_ATTR_NO_WARN, &nvme_dma_attrs);
+
return result;
}

--
1.8.3.1