Messages in this thread |  | | Subject | Re: [PATCH 13/16] nvme-pci: Convert to using dma_map_sg_p2pdma for p2pdma pages | From | John Hubbard <> | Date | Sun, 2 May 2021 18:34:39 -0700 |
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On 4/8/21 10:01 AM, Logan Gunthorpe wrote: > 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));
Nice simplification!
> 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; > + }
But now the "nr_mapped == 0" case is no longer doing an early out_free_sg. Is that OK?
> > 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; >
thanks, -- John Hubbard NVIDIA
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