iommu/amd: Split IOMMU group allocation and attach
Add a WARN_ON to make it clear why we don't add dma_pdev->dev to the
group we're allocating.
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 3a00b5ce..7fa97a5 100644
--- a/drivers/iommu/amd_iommu.c
+++ b/drivers/iommu/amd_iommu.c
@@ -325,6 +325,24 @@
return dma_pdev;
}
+static int use_pdev_iommu_group(struct pci_dev *pdev, struct device *dev)
+{
+ struct iommu_group *group = iommu_group_get(&pdev->dev);
+ int ret;
+
+ if (!group) {
+ group = iommu_group_alloc();
+ if (IS_ERR(group))
+ return PTR_ERR(group);
+
+ WARN_ON(&pdev->dev != dev);
+ }
+
+ ret = iommu_group_add_device(group, dev);
+ iommu_group_put(group);
+ return ret;
+}
+
static int init_iommu_group(struct device *dev)
{
struct iommu_dev_data *dev_data;
@@ -353,18 +371,8 @@
dma_pdev = pci_dev_get(to_pci_dev(dev));
dma_pdev = get_isolation_root(dma_pdev);
- group = iommu_group_get(&dma_pdev->dev);
+ ret = use_pdev_iommu_group(dma_pdev, dev);
pci_dev_put(dma_pdev);
- if (!group) {
- group = iommu_group_alloc();
- if (IS_ERR(group))
- return PTR_ERR(group);
- }
-
- ret = iommu_group_add_device(group, dev);
-
- iommu_group_put(group);
-
return ret;
}