iommu/vt-d: Use iommu_group_get_for_dev()

The IOMMU code now provides a common interface for finding or
creating an IOMMU group for a device on PCI buses.  Make use of it
and remove piles of code.

Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
Cc: David Woodhouse <dwmw2@infradead.org>
Signed-off-by: Joerg Roedel <jroedel@suse.de>

1 files changed, 4 insertions, 75 deletions

diff --git a/drivers/iommu/intel-iommu.c b/drivers/iommu/intel-iommu.c
index 51b6b77dc3e5..9128c84a51e7 100644
--- a/drivers/iommu/intel-iommu.c
+++ b/drivers/iommu/intel-iommu.c
@@ -45,7 +45,6 @@
 #include <asm/iommu.h>
 
 #include "irq_remapping.h"
-#include "pci.h"
 
 #define ROOT_SIZE               VTD_PAGE_SIZE
 #define CONTEXT_SIZE            VTD_PAGE_SIZE
@@ -4373,91 +4372,21 @@ static int intel_iommu_domain_has_cap(struct iommu_domain *domain,
         return 0;
 }
 
-#define REQ_ACS_FLAGS   (PCI_ACS_SV | PCI_ACS_RR | PCI_ACS_CR | PCI_ACS_UF)
-
 static int intel_iommu_add_device(struct device *dev)
 {
-        struct pci_dev *pdev = to_pci_dev(dev);
-        struct pci_dev *bridge, *dma_pdev = NULL;
         struct iommu_group *group;
-        int ret;
         u8 bus, devfn;
 
         if (!device_to_iommu(dev, &bus, &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);
-                if (!dma_pdev)
-                        dma_pdev = pci_dev_get(bridge);
-        } else
-                dma_pdev = pci_dev_get(pdev);
-
-        /* Account for quirked devices */
-        swap_pci_ref(&dma_pdev, pci_get_dma_source(dma_pdev));
-
-        /*
-         * If it's a multifunction device that does not support our
-         * required ACS flags, add to the same group as lowest numbered
-         * function that also does not suport the required ACS flags.
-         */
-        if (dma_pdev->multifunction &&
-            !pci_acs_enabled(dma_pdev, REQ_ACS_FLAGS)) {
-                u8 i, slot = PCI_SLOT(dma_pdev->devfn);
-
-                for (i = 0; i < 8; i++) {
-                        struct pci_dev *tmp;
-
-                        tmp = pci_get_slot(dma_pdev->bus, PCI_DEVFN(slot, i));
-                        if (!tmp)
-                                continue;
-
-                        if (!pci_acs_enabled(tmp, REQ_ACS_FLAGS)) {
-                                swap_pci_ref(&dma_pdev, tmp);
-                                break;
-                        }
-                        pci_dev_put(tmp);
-                }
-        }
-
-        /*
-         * Devices on the root bus go through the iommu.  If that's not us,
-         * find the next upstream device and test ACS up to the root bus.
-         * Finding the next device may require skipping virtual buses.
-         */
-        while (!pci_is_root_bus(dma_pdev->bus)) {
-                struct pci_bus *bus = dma_pdev->bus;
-
-                while (!bus->self) {
-                        if (!pci_is_root_bus(bus))
-                                bus = bus->parent;
-                        else
-                                goto root_bus;
-                }
-
-                if (pci_acs_path_enabled(bus->self, NULL, REQ_ACS_FLAGS))
-                        break;
-
-                swap_pci_ref(&dma_pdev, pci_dev_get(bus->self));
-        }
+        group = iommu_group_get_for_dev(dev);
 
-root_bus:
-        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);
+        if (IS_ERR(group))
+                return PTR_ERR(group);
 
         iommu_group_put(group);
-        return ret;
+        return 0;
 }
 
 static void intel_iommu_remove_device(struct device *dev)