From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932770AbeDWXcX (ORCPT ); Mon, 23 Apr 2018 19:32:23 -0400 Received: from ale.deltatee.com ([207.54.116.67]:41926 "EHLO ale.deltatee.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932654AbeDWXbF (ORCPT ); Mon, 23 Apr 2018 19:31:05 -0400 From: Logan Gunthorpe To: linux-kernel@vger.kernel.org, linux-pci@vger.kernel.org, linux-nvme@lists.infradead.org, linux-rdma@vger.kernel.org, linux-nvdimm@lists.01.org, linux-block@vger.kernel.org Cc: Stephen Bates , Christoph Hellwig , Jens Axboe , Keith Busch , Sagi Grimberg , Bjorn Helgaas , Jason Gunthorpe , Max Gurtovoy , Dan Williams , =?UTF-8?q?J=C3=A9r=C3=B4me=20Glisse?= , Benjamin Herrenschmidt , Alex Williamson , =?UTF-8?q?Christian=20K=C3=B6nig?= , Logan Gunthorpe Date: Mon, 23 Apr 2018 17:30:35 -0600 Message-Id: <20180423233046.21476-4-logang@deltatee.com> X-Mailer: git-send-email 2.11.0 In-Reply-To: <20180423233046.21476-1-logang@deltatee.com> References: <20180423233046.21476-1-logang@deltatee.com> X-SA-Exim-Connect-IP: 172.16.1.31 X-SA-Exim-Rcpt-To: linux-nvme@lists.infradead.org, linux-nvdimm@lists.01.org, linux-kernel@vger.kernel.org, linux-pci@vger.kernel.org, linux-rdma@vger.kernel.org, linux-block@vger.kernel.org, sbates@raithlin.com, hch@lst.de, axboe@kernel.dk, sagi@grimberg.me, bhelgaas@google.com, jgg@mellanox.com, maxg@mellanox.com, keith.busch@intel.com, dan.j.williams@intel.com, benh@kernel.crashing.org, jglisse@redhat.com, alex.williamson@redhat.com, christian.koenig@amd.com, logang@deltatee.com X-SA-Exim-Mail-From: gunthorp@deltatee.com Subject: [PATCH v4 03/14] PCI/P2PDMA: Add PCI p2pmem dma mappings to adjust the bus offset X-SA-Exim-Version: 4.2.1 (built Tue, 02 Aug 2016 21:08:31 +0000) X-SA-Exim-Scanned: Yes (on ale.deltatee.com) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org The DMA address used when mapping PCI P2P memory must be the PCI bus address. Thus, introduce pci_p2pmem_[un]map_sg() to map the correct addresses when using P2P memory. For this, we assume that an SGL passed to these functions contain all P2P memory or no P2P memory. Signed-off-by: Logan Gunthorpe --- drivers/pci/p2pdma.c | 51 ++++++++++++++++++++++++++++++++++++++++++++++ include/linux/memremap.h | 1 + include/linux/pci-p2pdma.h | 13 ++++++++++++ 3 files changed, 65 insertions(+) diff --git a/drivers/pci/p2pdma.c b/drivers/pci/p2pdma.c index 4daad6374869..ed9dce8552a2 100644 --- a/drivers/pci/p2pdma.c +++ b/drivers/pci/p2pdma.c @@ -190,6 +190,8 @@ int pci_p2pdma_add_resource(struct pci_dev *pdev, int bar, size_t size, pgmap->res.flags = pci_resource_flags(pdev, bar); pgmap->ref = &pdev->p2pdma->devmap_ref; pgmap->type = MEMORY_DEVICE_PCI_P2PDMA; + pgmap->pci_p2pdma_bus_offset = pci_bus_address(pdev, bar) - + pci_resource_start(pdev, bar); addr = devm_memremap_pages(&pdev->dev, pgmap); if (IS_ERR(addr)) { @@ -746,3 +748,52 @@ void pci_p2pmem_publish(struct pci_dev *pdev, bool publish) pdev->p2pdma->p2pmem_published = publish; } EXPORT_SYMBOL_GPL(pci_p2pmem_publish); + +/** + * pci_p2pdma_map_sg - map a PCI peer-to-peer sg for DMA + * @dev: device doing the DMA request + * @sg: scatter list to map + * @nents: elements in the scatterlist + * @dir: DMA direction + * + * Returns the number of SG entries mapped + */ +int pci_p2pdma_map_sg(struct device *dev, struct scatterlist *sg, int nents, + enum dma_data_direction dir) +{ + struct dev_pagemap *pgmap; + struct scatterlist *s; + phys_addr_t paddr; + int i; + + /* + * p2pdma mappings are not compatible with devices that use + * dma_virt_ops. + */ + if (IS_ENABLED(CONFIG_DMA_VIRT_OPS) && dev->dma_ops == &dma_virt_ops) + return 0; + + for_each_sg(sg, s, nents, i) { + pgmap = sg_page(s)->pgmap; + paddr = sg_phys(s); + + s->dma_address = paddr - pgmap->pci_p2pdma_bus_offset; + sg_dma_len(s) = s->length; + } + + return nents; +} +EXPORT_SYMBOL_GPL(pci_p2pdma_map_sg); + +/** + * pci_p2pdma_unmap_sg - unmap a PCI peer-to-peer sg for DMA + * @dev: device doing the DMA request + * @sg: scatter list to map + * @nents: elements in the scatterlist + * @dir: DMA direction + */ +void pci_p2pdma_unmap_sg(struct device *dev, struct scatterlist *sg, int nents, + enum dma_data_direction dir) +{ +} +EXPORT_SYMBOL_GPL(pci_p2pdma_unmap_sg); diff --git a/include/linux/memremap.h b/include/linux/memremap.h index 9e907c338a44..1660f64ce96f 100644 --- a/include/linux/memremap.h +++ b/include/linux/memremap.h @@ -125,6 +125,7 @@ struct dev_pagemap { struct device *dev; void *data; enum memory_type type; + u64 pci_p2pdma_bus_offset; }; #ifdef CONFIG_ZONE_DEVICE diff --git a/include/linux/pci-p2pdma.h b/include/linux/pci-p2pdma.h index 80e931cb1235..0cde88341eeb 100644 --- a/include/linux/pci-p2pdma.h +++ b/include/linux/pci-p2pdma.h @@ -35,6 +35,10 @@ struct scatterlist *pci_p2pmem_alloc_sgl(struct pci_dev *pdev, unsigned int *nents, u32 length); 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(struct device *dev, struct scatterlist *sg, int nents, + enum dma_data_direction dir); +void pci_p2pdma_unmap_sg(struct device *dev, struct scatterlist *sg, int nents, + enum dma_data_direction dir); #else /* CONFIG_PCI_P2PDMA */ static inline int pci_p2pdma_add_resource(struct pci_dev *pdev, int bar, size_t size, u64 offset) @@ -96,5 +100,14 @@ static inline void pci_p2pmem_free_sgl(struct pci_dev *pdev, static inline void pci_p2pmem_publish(struct pci_dev *pdev, bool publish) { } +static inline int pci_p2pdma_map_sg(struct device *dev, + struct scatterlist *sg, int nents, enum dma_data_direction dir) +{ + return 0; +} +static inline void pci_p2pdma_unmap_sg(struct device *dev, + struct scatterlist *sg, int nents, enum dma_data_direction dir) +{ +} #endif /* CONFIG_PCI_P2PDMA */ #endif /* _LINUX_PCI_P2P_H */ -- 2.11.0