iommu/amd: Split IOMMU Group topology walk

Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>

diff --git a/drivers/iommu/amd_iommu.c b/drivers/iommu/amd_iommu.c
index b65b377..6edbd0e 100644 (file)
--- a/drivers/iommu/amd_iommu.c
+++ b/drivers/iommu/amd_iommu.c
@@ -276,32 +276,9 @@ static void swap_pci_ref(struct pci_dev **from, struct pci_dev *to)
 
 #define REQ_ACS_FLAGS  (PCI_ACS_SV | PCI_ACS_RR | PCI_ACS_CR | PCI_ACS_UF)
 
-static int init_iommu_group(struct device *dev)
+static struct pci_dev *get_isolation_root(struct pci_dev *pdev)
 {
-       struct iommu_dev_data *dev_data;
-       struct iommu_group *group;
-       struct pci_dev *dma_pdev = NULL;
-       int ret;
-
-       group = iommu_group_get(dev);
-       if (group) {
-               iommu_group_put(group);
-               return 0;
-       }
-
-       dev_data = find_dev_data(get_device_id(dev));
-       if (!dev_data)
-               return -ENOMEM;
-
-       if (dev_data->alias_data) {
-               u16 alias;
-
-               alias = amd_iommu_alias_table[dev_data->devid];
-               dma_pdev = pci_get_bus_and_slot(alias >> 8, alias & 0xff);
-       }
-
-       if (!dma_pdev)
-               dma_pdev = pci_dev_get(to_pci_dev(dev));
+       struct pci_dev *dma_pdev = pdev;
 
        /* Account for quirked devices */
        swap_pci_ref(&dma_pdev, pci_get_dma_source(dma_pdev));
@@ -339,6 +316,37 @@ static int init_iommu_group(struct device *dev)
        }
 
 root_bus:
+       return dma_pdev;
+}
+
+static int init_iommu_group(struct device *dev)
+{
+       struct iommu_dev_data *dev_data;
+       struct iommu_group *group;
+       struct pci_dev *dma_pdev = NULL;
+       int ret;
+
+       group = iommu_group_get(dev);
+       if (group) {
+               iommu_group_put(group);
+               return 0;
+       }
+
+       dev_data = find_dev_data(get_device_id(dev));
+       if (!dev_data)
+               return -ENOMEM;
+
+       if (dev_data->alias_data) {
+               u16 alias;
+
+               alias = amd_iommu_alias_table[dev_data->devid];
+               dma_pdev = pci_get_bus_and_slot(alias >> 8, alias & 0xff);
+       }
+
+       if (!dma_pdev)
+               dma_pdev = pci_dev_get(to_pci_dev(dev));
+
+       dma_pdev = get_isolation_root(dma_pdev);
        group = iommu_group_get(&dma_pdev->dev);
        pci_dev_put(dma_pdev);
        if (!group) {