[RFC PATCH 3/3] set full_buffer_write for nvme devices.

[Jianxiong Gao]

NVMe dma operations always overwrite the whole dma buffer passed to
the device. Making use the newly introduced full_buffer_write flag
so in cases swiotlb is used to bounce the buffer, we no longer need
to do the extra copy on preparing the buffer.

Signed-off-by: Jianxiong Gao <jxgao at google.com>
---
 drivers/nvme/host/pci.c | 1 +
 1 file changed, 1 insertion(+)

diff --git a/drivers/nvme/host/pci.c b/drivers/nvme/host/pci.c
index 278bed4e35bb..8fb6a0a87202 100644
--- a/drivers/nvme/host/pci.c
+++ b/drivers/nvme/host/pci.c
@@ -3209,6 +3209,7 @@ static struct nvme_dev *nvme_pci_alloc_dev(struct pci_dev *pdev,
 		dma_set_mask_and_coherent(&pdev->dev, DMA_BIT_MASK(48));
 	else
 		dma_set_mask_and_coherent(&pdev->dev, DMA_BIT_MASK(64));
+	dma_set_full_buffer_write(&pdev->dev, true);
 	dma_set_min_align_mask(&pdev->dev, NVME_CTRL_PAGE_SIZE - 1);
 	dma_set_max_seg_size(&pdev->dev, 0xffffffff);
 
-- 
2.48.1.362.g079036d154-goog