intel-iommu: Support IOMMU groups

Add IOMMU group support to Intel VT-d code.  This driver sets up
devices ondemand, so make use of the add_device/remove_device
callbacks in IOMMU API to manage setting up the groups.

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

1 files changed, 43 insertions, 0 deletions

diff --git a/drivers/iommu/intel-iommu.c b/drivers/iommu/intel-iommu.c
index c62f2df25221..4a434528cd1c 100644
--- a/drivers/iommu/intel-iommu.c
+++ b/drivers/iommu/intel-iommu.c
@@ -4090,6 +4090,47 @@ static int intel_iommu_domain_has_cap(struct iommu_domain *domain,
         return 0;
 }
 
+static int intel_iommu_add_device(struct device *dev)
+{
+        struct pci_dev *pdev = to_pci_dev(dev);
+        struct pci_dev *bridge, *dma_pdev;
+        struct iommu_group *group;
+        int ret;
+
+        if (!device_to_iommu(pci_domain_nr(pdev->bus),
+                             pdev->bus->number, pdev->devfn))
+                return -ENODEV;
+
+        bridge = pci_find_upstream_pcie_bridge(pdev);
+        if (bridge) {
+                if (pci_is_pcie(bridge))
+                        dma_pdev = pci_get_domain_bus_and_slot(
+                                                pci_domain_nr(pdev->bus),
+                                                bridge->subordinate->number, 0);
+                else
+                        dma_pdev = pci_dev_get(bridge);
+        } else
+                dma_pdev = pci_dev_get(pdev);
+
+        group = iommu_group_get(&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;
+}
+
+static void intel_iommu_remove_device(struct device *dev)
+{
+        iommu_group_remove_device(dev);
+}
+
 static struct iommu_ops intel_iommu_ops = {
         .domain_init    = intel_iommu_domain_init,
         .domain_destroy = intel_iommu_domain_destroy,
@@ -4099,6 +4140,8 @@ static struct iommu_ops intel_iommu_ops = {
         .unmap          = intel_iommu_unmap,
         .iova_to_phys   = intel_iommu_iova_to_phys,
         .domain_has_cap = intel_iommu_domain_has_cap,
+        .add_device     = intel_iommu_add_device,
+        .remove_device  = intel_iommu_remove_device,
         .pgsize_bitmap  = INTEL_IOMMU_PGSIZES,
 };