iommu/vt-d: Add device_def_domain_type() helper

This helper returns the default domain type that the device
requires.

Signed-off-by: Lu Baolu <baolu.lu@linux.intel.com>
Signed-off-by: Joerg Roedel <jroedel@suse.de>

diff --git a/drivers/iommu/intel-iommu.c b/drivers/iommu/intel-iommu.c
index 1bd2251..9db0f7f 100644 (file)
--- a/drivers/iommu/intel-iommu.c
+++ b/drivers/iommu/intel-iommu.c
@@ -2930,29 +2930,37 @@ static bool device_is_rmrr_locked(struct device *dev)
        return true;
 }
 
-static int iommu_should_identity_map(struct device *dev, int startup)
+/*
+ * Return the required default domain type for a specific device.
+ *
+ * @dev: the device in query
+ * @startup: true if this is during early boot
+ *
+ * Returns:
+ *  - IOMMU_DOMAIN_DMA: device requires a dynamic mapping domain
+ *  - IOMMU_DOMAIN_IDENTITY: device requires an identical mapping domain
+ *  - 0: both identity and dynamic domains work for this device
+ */
+static int device_def_domain_type(struct device *dev, int startup)
 {
        if (dev_is_pci(dev)) {
                struct pci_dev *pdev = to_pci_dev(dev);
 
                if (device_is_rmrr_locked(dev))
-                       return 0;
+                       return IOMMU_DOMAIN_DMA;
 
                /*
                 * Prevent any device marked as untrusted from getting
                 * placed into the statically identity mapping domain.
                 */
                if (pdev->untrusted)
-                       return 0;
+                       return IOMMU_DOMAIN_DMA;
 
                if ((iommu_identity_mapping & IDENTMAP_AZALIA) && IS_AZALIA(pdev))
-                       return 1;
+                       return IOMMU_DOMAIN_IDENTITY;
 
                if ((iommu_identity_mapping & IDENTMAP_GFX) && IS_GFX_DEVICE(pdev))
-                       return 1;
-
-               if (!(iommu_identity_mapping & IDENTMAP_ALL))
-                       return 0;
+                       return IOMMU_DOMAIN_IDENTITY;
 
                /*
                 * We want to start off with all devices in the 1:1 domain, and
@@ -2973,14 +2981,14 @@ static int iommu_should_identity_map(struct device *dev, int startup)
                 */
                if (!pci_is_pcie(pdev)) {
                        if (!pci_is_root_bus(pdev->bus))
-                               return 0;
+                               return IOMMU_DOMAIN_DMA;
                        if (pdev->class >> 8 == PCI_CLASS_BRIDGE_PCI)
-                               return 0;
+                               return IOMMU_DOMAIN_DMA;
                } else if (pci_pcie_type(pdev) == PCI_EXP_TYPE_PCI_BRIDGE)
-                       return 0;
+                       return IOMMU_DOMAIN_DMA;
        } else {
                if (device_has_rmrr(dev))
-                       return 0;
+                       return IOMMU_DOMAIN_DMA;
        }
 
        /*
@@ -3002,7 +3010,13 @@ static int iommu_should_identity_map(struct device *dev, int startup)
                return dma_mask >= dma_get_required_mask(dev);
        }
 
-       return 1;
+       return (iommu_identity_mapping & IDENTMAP_ALL) ?
+                       IOMMU_DOMAIN_IDENTITY : 0;
+}
+
+static inline int iommu_should_identity_map(struct device *dev, int startup)
+{
+       return device_def_domain_type(dev, startup) == IOMMU_DOMAIN_IDENTITY;
 }
 
 static int __init dev_prepare_static_identity_mapping(struct device *dev, int hw)