iommu: Revive device_group iommu-ops call-back

That call-back is currently unused, change it into a
call-back function for finding the right IOMMU group for a
device.
This is a first step to remove the hard-coded PCI dependency
in the iommu-group code.

Signed-off-by: Joerg Roedel <jroedel@suse.de>

2 files changed, 7 insertions, 4 deletions

diff --git a/drivers/iommu/iommu.c b/drivers/iommu/iommu.c
index 049df495c274..563746383973 100644
--- a/drivers/iommu/iommu.c
+++ b/drivers/iommu/iommu.c
@@ -814,6 +814,7 @@ static struct iommu_group *iommu_group_get_for_pci_dev(struct pci_dev *pdev)
  */
 struct iommu_group *iommu_group_get_for_dev(struct device *dev)
 {
+        const struct iommu_ops *ops = dev->bus->iommu_ops;
         struct iommu_group *group;
         int ret;
 
@@ -821,10 +822,12 @@ struct iommu_group *iommu_group_get_for_dev(struct device *dev)
         if (group)
                 return group;
 
-        if (!dev_is_pci(dev))
-                return ERR_PTR(-EINVAL);
+        group = ERR_PTR(-EINVAL);
 
-        group = iommu_group_get_for_pci_dev(to_pci_dev(dev));
+        if (ops && ops->device_group)
+                group = ops->device_group(dev);
+        else if (dev_is_pci(dev))
+                group = iommu_group_get_for_pci_dev(to_pci_dev(dev));
 
         if (IS_ERR(group))
                 return group;
diff --git a/include/linux/iommu.h b/include/linux/iommu.h
index f174506a5343..a1e6e8914c17 100644
--- a/include/linux/iommu.h
+++ b/include/linux/iommu.h
@@ -168,7 +168,7 @@ struct iommu_ops {
         phys_addr_t (*iova_to_phys)(struct iommu_domain *domain, dma_addr_t iova);
         int (*add_device)(struct device *dev);
         void (*remove_device)(struct device *dev);
-        int (*device_group)(struct device *dev, unsigned int *groupid);
+        struct iommu_group *(*device_group)(struct device *dev);
         int (*domain_get_attr)(struct iommu_domain *domain,
                                enum iommu_attr attr, void *data);
         int (*domain_set_attr)(struct iommu_domain *domain,