Any requests that traverse the host bridge will need to be mapped into the IOMMU, so call dma_map_sg() inside pci_p2pdma_map_sg() when appropriate. Similarly, call dma_unmap_sg() inside pci_p2pdma_unmap_sg(). Link: https://lore.kernel.org/r/20190730163545.4915-13-logang@xxxxxxxxxxxx Signed-off-by: Logan Gunthorpe <logang@xxxxxxxxxxxx> Signed-off-by: Bjorn Helgaas <bhelgaas@xxxxxxxxxx> --- drivers/pci/p2pdma.c | 40 +++++++++++++++++++++++++++++++++++++++- 1 file changed, 39 insertions(+), 1 deletion(-) diff --git a/drivers/pci/p2pdma.c b/drivers/pci/p2pdma.c index db8224ff6e80..bca1ffc7075e 100644 --- a/drivers/pci/p2pdma.c +++ b/drivers/pci/p2pdma.c @@ -807,6 +807,16 @@ void pci_p2pmem_publish(struct pci_dev *pdev, bool publish) } EXPORT_SYMBOL_GPL(pci_p2pmem_publish); +static enum pci_p2pdma_map_type pci_p2pdma_map_type(struct pci_dev *provider, + struct pci_dev *client) +{ + if (!provider->p2pdma) + return PCI_P2PDMA_MAP_NOT_SUPPORTED; + + return xa_to_value(xa_load(&provider->p2pdma->map_types, + map_types_idx(client))); +} + static int __pci_p2pdma_map_sg(struct pci_p2pdma_pagemap *p2p_pgmap, struct device *dev, struct scatterlist *sg, int nents) { @@ -852,8 +862,22 @@ int pci_p2pdma_map_sg_attrs(struct device *dev, struct scatterlist *sg, { struct pci_p2pdma_pagemap *p2p_pgmap = to_p2p_pgmap(sg_page(sg)->pgmap); + struct pci_dev *client; - return __pci_p2pdma_map_sg(p2p_pgmap, dev, sg, nents); + if (WARN_ON_ONCE(!dev_is_pci(dev))) + return 0; + + client = to_pci_dev(dev); + + switch (pci_p2pdma_map_type(p2p_pgmap->provider, client)) { + case PCI_P2PDMA_MAP_THRU_HOST_BRIDGE: + return dma_map_sg_attrs(dev, sg, nents, dir, attrs); + case PCI_P2PDMA_MAP_BUS_ADDR: + return __pci_p2pdma_map_sg(p2p_pgmap, dev, sg, nents); + default: + WARN_ON_ONCE(1); + return 0; + } } EXPORT_SYMBOL_GPL(pci_p2pdma_map_sg_attrs); @@ -869,6 +893,20 @@ EXPORT_SYMBOL_GPL(pci_p2pdma_map_sg_attrs); void pci_p2pdma_unmap_sg_attrs(struct device *dev, struct scatterlist *sg, int nents, enum dma_data_direction dir, unsigned long attrs) { + struct pci_p2pdma_pagemap *p2p_pgmap = + to_p2p_pgmap(sg_page(sg)->pgmap); + enum pci_p2pdma_map_type map_type; + struct pci_dev *client; + + if (WARN_ON_ONCE(!dev_is_pci(dev))) + return; + + client = to_pci_dev(dev); + + map_type = pci_p2pdma_map_type(p2p_pgmap->provider, client); + + if (map_type == PCI_P2PDMA_MAP_THRU_HOST_BRIDGE) + dma_unmap_sg_attrs(dev, sg, nents, dir, attrs); } EXPORT_SYMBOL_GPL(pci_p2pdma_unmap_sg_attrs); -- 2.20.1
