---

yaml --- r: 316582 b: refs/heads/master c: 664b600 h: refs/heads/master v: v3
git-mirror · Jun 25, 2012 · a42af7f · a42af7f
1 parent a1da2b4
commit a42af7f
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Showing 2 changed files with 26 additions and 1 deletion.
diff --git a/[refs] b/[refs]
@@ -1,2 +1,2 @@
 ---
-refs/heads/master: abdfdde2534c48d7a761fc437ad3d840a5947dbc
+refs/heads/master: 664b600331128146d8ddd3e004defe23ba5c47dc
diff --git a/trunk/drivers/iommu/amd_iommu.c b/trunk/drivers/iommu/amd_iommu.c
@@ -254,6 +254,14 @@ static bool check_device(struct device *dev)
 	return true;
 }
 
+static void swap_pci_ref(struct pci_dev **from, struct pci_dev *to)
+{
+	pci_dev_put(*from);
+	*from = to;
+}
+
+#define REQ_ACS_FLAGS	(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);
@@ -286,6 +294,23 @@ static int iommu_init_device(struct device *dev)
 	} else
 		dma_pdev = pci_dev_get(pdev);
 
+	swap_pci_ref(&dma_pdev, pci_get_dma_source(dma_pdev));
+
+	if (dma_pdev->multifunction &&
+	    !pci_acs_enabled(dma_pdev, REQ_ACS_FLAGS))
+		swap_pci_ref(&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, REQ_ACS_FLAGS))
+			break;
+
+		swap_pci_ref(&dma_pdev, pci_dev_get(dma_pdev->bus->self));
+	}
+
 	group = iommu_group_get(&dma_pdev->dev);
 	pci_dev_put(dma_pdev);
 	if (!group) {