Add pci_p2pdma_unmap_sg() to the two places that call pci_p2pdma_map_sg(). This is a prep patch to introduce correct mappings for p2pdma transactions that go through the root complex. Link: https://lore.kernel.org/r/20190730163545.4915-10-logang@xxxxxxxxxxxx Signed-off-by: Logan Gunthorpe <logang@xxxxxxxxxxxx> Signed-off-by: Bjorn Helgaas <bhelgaas@xxxxxxxxxx> --- drivers/infiniband/core/rw.c | 6 ++++-- drivers/nvme/host/pci.c | 6 ++++-- drivers/pci/p2pdma.c | 18 +++++++++++++++++- include/linux/pci-p2pdma.h | 13 +++++++++++++ 4 files changed, 38 insertions(+), 5 deletions(-) diff --git a/drivers/infiniband/core/rw.c b/drivers/infiniband/core/rw.c index dce06108c8c3..5337393d4dfe 100644 --- a/drivers/infiniband/core/rw.c +++ b/drivers/infiniband/core/rw.c @@ -583,8 +583,10 @@ void rdma_rw_ctx_destroy(struct rdma_rw_ctx *ctx, struct ib_qp *qp, u8 port_num, break; } - /* P2PDMA contexts do not need to be unmapped */ - if (!is_pci_p2pdma_page(sg_page(sg))) + if (is_pci_p2pdma_page(sg_page(sg))) + pci_p2pdma_unmap_sg(qp->pd->device->dma_device, sg, + sg_cnt, dir); + else ib_dma_unmap_sg(qp->pd->device, sg, sg_cnt, dir); } EXPORT_SYMBOL(rdma_rw_ctx_destroy); diff --git a/drivers/nvme/host/pci.c b/drivers/nvme/host/pci.c index f97bb031228a..0f92cca7a860 100644 --- a/drivers/nvme/host/pci.c +++ b/drivers/nvme/host/pci.c @@ -547,8 +547,10 @@ static void nvme_unmap_data(struct nvme_dev *dev, struct request *req) WARN_ON_ONCE(!iod->nents); - /* P2PDMA requests do not need to be unmapped */ - if (!is_pci_p2pdma_page(sg_page(iod->sg))) + 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)); diff --git a/drivers/pci/p2pdma.c b/drivers/pci/p2pdma.c index 94fbacbcbbd0..1eec7a5ec27e 100644 --- a/drivers/pci/p2pdma.c +++ b/drivers/pci/p2pdma.c @@ -800,7 +800,8 @@ EXPORT_SYMBOL_GPL(pci_p2pmem_publish); * @dir: DMA direction * @attrs: DMA attributes passed to dma_map_sg() (if called) * - * Scatterlists mapped with this function should not be unmapped in any way. + * Scatterlists mapped with this function should be unmapped using + * pci_p2pdma_unmap_sg_attrs(). * * Returns the number of SG entries mapped or 0 on error. */ @@ -834,6 +835,21 @@ int pci_p2pdma_map_sg_attrs(struct device *dev, struct scatterlist *sg, } EXPORT_SYMBOL_GPL(pci_p2pdma_map_sg_attrs); +/** + * pci_p2pdma_unmap_sg - unmap a PCI peer-to-peer scatterlist that was + * mapped with pci_p2pdma_map_sg() + * @dev: device doing the DMA request + * @sg: scatter list to map + * @nents: number of elements returned by pci_p2pdma_map_sg() + * @dir: DMA direction + * @attrs: DMA attributes passed to dma_unmap_sg() (if called) + */ +void pci_p2pdma_unmap_sg_attrs(struct device *dev, struct scatterlist *sg, + int nents, enum dma_data_direction dir, unsigned long attrs) +{ +} +EXPORT_SYMBOL_GPL(pci_p2pdma_unmap_sg_attrs); + /** * pci_p2pdma_enable_store - parse a configfs/sysfs attribute store * to enable p2pdma diff --git a/include/linux/pci-p2pdma.h b/include/linux/pci-p2pdma.h index 7fd51954f93a..8318a97c9c61 100644 --- a/include/linux/pci-p2pdma.h +++ b/include/linux/pci-p2pdma.h @@ -32,6 +32,8 @@ void pci_p2pmem_free_sgl(struct pci_dev *pdev, struct scatterlist *sgl); void pci_p2pmem_publish(struct pci_dev *pdev, bool publish); int pci_p2pdma_map_sg_attrs(struct device *dev, struct scatterlist *sg, int nents, enum dma_data_direction dir, unsigned long attrs); +void pci_p2pdma_unmap_sg_attrs(struct device *dev, struct scatterlist *sg, + int nents, enum dma_data_direction dir, unsigned long attrs); int pci_p2pdma_enable_store(const char *page, struct pci_dev **p2p_dev, bool *use_p2pdma); ssize_t pci_p2pdma_enable_show(char *page, struct pci_dev *p2p_dev, @@ -87,6 +89,11 @@ static inline int pci_p2pdma_map_sg_attrs(struct device *dev, { return 0; } +static inline void pci_p2pdma_unmap_sg_attrs(struct device *dev, + struct scatterlist *sg, int nents, enum dma_data_direction dir, + unsigned long attrs) +{ +} static inline int pci_p2pdma_enable_store(const char *page, struct pci_dev **p2p_dev, bool *use_p2pdma) { @@ -118,4 +125,10 @@ static inline int pci_p2pdma_map_sg(struct device *dev, struct scatterlist *sg, return pci_p2pdma_map_sg_attrs(dev, sg, nents, dir, 0); } +static inline void pci_p2pdma_unmap_sg(struct device *dev, + struct scatterlist *sg, int nents, enum dma_data_direction dir) +{ + pci_p2pdma_unmap_sg_attrs(dev, sg, nents, dir, 0); +} + #endif /* _LINUX_PCI_P2P_H */ -- 2.20.1
