From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: From: Alex Williamson Subject: [PATCH 5/7] amd_iommu: Make use of DMA quirks and ACS checks in IOMMU groups To: joerg.roedel@amd.com, dwmw2@infradead.org, iommu@lists.linux-foundation.org Cc: bhelgaas@google.com, benh@kernel.crashing.org, aik@ozlabs.ru, david@gibson.dropbear.id.au, konrad.wilk@oracle.com, linux-kernel@vger.kernel.org, linux-pci@vger.kernel.org, gregkh@linuxfoundation.org, ddutile@redhat.com, alex.williamson@redhat.com Date: Tue, 29 May 2012 23:10:34 -0600 Message-ID: <20120530051034.1543.46304.stgit@bling.home> In-Reply-To: <20120530045150.1543.73660.stgit@bling.home> References: <20120530045150.1543.73660.stgit@bling.home> MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Sender: linux-kernel-owner@vger.kernel.org List-ID: Work around broken devices and adhere to ACS support when determining IOMMU grouping. Signed-off-by: Alex Williamson --- drivers/iommu/amd_iommu.c | 18 ++++++++++++++++++ 1 file changed, 18 insertions(+) diff --git a/drivers/iommu/amd_iommu.c b/drivers/iommu/amd_iommu.c index c0385b3..9b2e2c9 100644 --- a/drivers/iommu/amd_iommu.c +++ b/drivers/iommu/amd_iommu.c @@ -254,6 +254,8 @@ static bool check_device(struct device *dev) return true; } +#define PCI_ACS_ENABLED (PCI_ACS_SV | PCI_ACS_RR | PCI_ACS_CR | PCI_ACS_UF) + static int iommu_init_device(struct device *dev) { struct pci_dev *dma_pdev, *pdev = to_pci_dev(dev); @@ -291,6 +293,22 @@ static int iommu_init_device(struct device *dev) dma_pdev = pci_get_slot(pdev->bus, PCI_DEVFN(PCI_SLOT(pdev->devfn), 0)); + dma_pdev = pci_dma_source(dma_pdev); + + if (dma_pdev->multifunction && + !pci_acs_enabled(dma_pdev, PCI_ACS_ENABLED)) + dma_pdev = pci_get_slot(dma_pdev->bus, + PCI_DEVFN(PCI_SLOT(dma_pdev->devfn), + 0)); + + while (!pci_is_root_bus(dma_pdev->bus)) { + if (pci_acs_path_enabled(dma_pdev->bus->self, + NULL, PCI_ACS_ENABLED)) + break; + + dma_pdev = dma_pdev->bus->self; + } + group = iommu_group_get(&dma_pdev->dev); if (!group) { group = iommu_group_alloc();