[PATCH 13/16] nvme-pci: Convert to using dma_map_sg_p2pdma for p2pdma pages

Logan Gunthorpe
2021-04-08T17:01:49Z

Convert to using dma_map_sg_p2pdma() for PCI p2pdma pages.

This should be equivalent but allows for heterogeneous scatterlists
with both P2PDMA and regular pages. However, P2PDMA support will be
slightly more restricted (only dma-direct and dma-iommu are currently
supported).

Signed-off-by: Logan Gunthorpe <logang@deltatee.com>
---
drivers/nvme/host/pci.c | 28 ++++++++--------------------
1 file changed, 8 insertions(+), 20 deletions(-)

diff --git a/drivers/nvme/host/pci.c b/drivers/nvme/host/pci.c
index 14f092973792..a1ed07ff38b7 100644
--- a/drivers/nvme/host/pci.c
+++ b/drivers/nvme/host/pci.c
@@ -577,17 +577,6 @@ static void nvme_free_sgls(struct nvme_dev *dev, struct request *req)

}

-static void nvme_unmap_sg(struct nvme_dev *dev, struct request *req)
-{
- struct nvme_iod *iod = blk_mq_rq_to_pdu(req);
-
- if (is_pci_p2pdma_page(sg_page(iod->sg)))
- pci_p2pdma_unmap_sg(dev->dev, iod->sg, iod->nents,
- rq_dma_dir(req));
- else
- dma_unmap_sg(dev->dev, iod->sg, iod->nents, rq_dma_dir(req));
-}
-
static void nvme_unmap_data(struct nvme_dev *dev, struct request *req)
{
struct nvme_iod *iod = blk_mq_rq_to_pdu(req);
@@ -600,7 +589,7 @@ static void nvme_unmap_data(struct nvme_dev *dev, struct request *req)

WARN_ON_ONCE(!iod->nents);

- nvme_unmap_sg(dev, req);
+ dma_unmap_sg(dev->dev, iod->sg, iod->nents, rq_dma_dir(req));
if (iod->npages == 0)
dma_pool_free(dev->prp_small_pool, nvme_pci_iod_list(req)[0],
iod->first_dma);
@@ -868,14 +857,13 @@ static blk_status_t nvme_map_data(struct nvme_dev *dev, struct request *req,
if (!iod->nents)
goto out_free_sg;

- if (is_pci_p2pdma_page(sg_page(iod->sg)))
- nr_mapped = pci_p2pdma_map_sg_attrs(dev->dev, iod->sg,
- iod->nents, rq_dma_dir(req), DMA_ATTR_NO_WARN);
- else
- nr_mapped = dma_map_sg_attrs(dev->dev, iod->sg, iod->nents,
- rq_dma_dir(req), DMA_ATTR_NO_WARN);
- if (!nr_mapped)
+ nr_mapped = dma_map_sg_p2pdma_attrs(dev->dev, iod->sg, iod->nents,
+ rq_dma_dir(req), DMA_ATTR_NO_WARN);
+ if (nr_mapped < 0) {
+ if (nr_mapped != -ENOMEM)
+ ret = BLK_STS_TARGET;
goto out_free_sg;
+ }

iod->use_sgl = nvme_pci_use_sgls(dev, req);
if (iod->use_sgl)
@@ -887,7 +875,7 @@ static blk_status_t nvme_map_data(struct nvme_dev *dev, struct request *req,
return BLK_STS_OK;

out_unmap_sg:
- nvme_unmap_sg(dev, req);
+ dma_unmap_sg(dev->dev, iod->sg, iod->nents, rq_dma_dir(req));
out_free_sg:
mempool_free(iod->sg, dev->iod_mempool);
return ret;
--
2.20.1