From: Logan Gunthorpe Date: Tue, 2 Jul 2019 17:35:44 +0000 (-0600) Subject: PCI/P2PDMA: Fix missing check for dma_virt_ops X-Git-Url: http://git.maquefel.me/?a=commitdiff_plain;h=9c002bb66f5bd8b8f470926489a115b7f486f501;p=linux.git PCI/P2PDMA: Fix missing check for dma_virt_ops Drivers that use dma_virt_ops were meant to be rejected when testing compatibility for P2PDMA. This check got inadvertently dropped in one of the later versions of the original patchset, so add it back. Fixes: 52916982af48 ("PCI/P2PDMA: Support peer-to-peer memory") Link: https://lore.kernel.org/r/20190702173544.21950-1-logang@deltatee.com Signed-off-by: Logan Gunthorpe Signed-off-by: Bjorn Helgaas --- diff --git a/drivers/pci/p2pdma.c b/drivers/pci/p2pdma.c index 742928d0053ec..1940a7a0a6840 100644 --- a/drivers/pci/p2pdma.c +++ b/drivers/pci/p2pdma.c @@ -468,6 +468,14 @@ int pci_p2pdma_distance_many(struct pci_dev *provider, struct device **clients, return -1; for (i = 0; i < num_clients; i++) { + if (IS_ENABLED(CONFIG_DMA_VIRT_OPS) && + clients[i]->dma_ops == &dma_virt_ops) { + if (verbose) + dev_warn(clients[i], + "cannot be used for peer-to-peer DMA because the driver makes use of dma_virt_ops\n"); + return -1; + } + pci_client = find_parent_pci_dev(clients[i]); if (!pci_client) { if (verbose) @@ -732,7 +740,7 @@ int pci_p2pdma_map_sg(struct device *dev, struct scatterlist *sg, int nents, * p2pdma mappings are not compatible with devices that use * dma_virt_ops. If the upper layers do the right thing * this should never happen because it will be prevented - * by the check in pci_p2pdma_add_client() + * by the check in pci_p2pdma_distance_many() */ if (WARN_ON_ONCE(IS_ENABLED(CONFIG_DMA_VIRT_OPS) && dev->dma_ops == &dma_virt_ops))