iommu: Add probe_device() and release_device() call-backs

Add call-backs to 'struct iommu_ops' as an alternative to the
add_device() and remove_device() call-backs, which will be removed when
all drivers are converted.

The new call-backs will not setup IOMMU groups and domains anymore,
so also add a probe_finalize() call-back where the IOMMU driver can do
per-device setup work which require the device to be set up with a
group and a domain.

Signed-off-by: Joerg Roedel <jroedel@suse.de>
Tested-by: Marek Szyprowski <m.szyprowski@samsung.com>
Acked-by: Marek Szyprowski <m.szyprowski@samsung.com>
Link: https://lore.kernel.org/r/20200429133712.31431-8-joro@8bytes.org
Signed-off-by: Joerg Roedel <jroedel@suse.de>

diff --git a/drivers/iommu/iommu.c b/drivers/iommu/iommu.c
index 5877abd..6cfe779 100644 (file)
--- a/drivers/iommu/iommu.c
+++ b/drivers/iommu/iommu.c
@@ -174,6 +174,36 @@ static void dev_iommu_free(struct device *dev)
        dev->iommu = NULL;
 }
 
+static int __iommu_probe_device(struct device *dev)
+{
+       const struct iommu_ops *ops = dev->bus->iommu_ops;
+       struct iommu_device *iommu_dev;
+       struct iommu_group *group;
+       int ret;
+
+       iommu_dev = ops->probe_device(dev);
+       if (IS_ERR(iommu_dev))
+               return PTR_ERR(iommu_dev);
+
+       dev->iommu->iommu_dev = iommu_dev;
+
+       group = iommu_group_get_for_dev(dev);
+       if (!IS_ERR(group)) {
+               ret = PTR_ERR(group);
+               goto out_release;
+       }
+       iommu_group_put(group);
+
+       iommu_device_link(iommu_dev, dev);
+
+       return 0;
+
+out_release:
+       ops->release_device(dev);
+
+       return ret;
+}
+
 int iommu_probe_device(struct device *dev)
 {
        const struct iommu_ops *ops = dev->bus->iommu_ops;
@@ -191,10 +221,17 @@ int iommu_probe_device(struct device *dev)
                goto err_free_dev_param;
        }
 
-       ret = ops->add_device(dev);
+       if (ops->probe_device)
+               ret = __iommu_probe_device(dev);
+       else
+               ret = ops->add_device(dev);
+
        if (ret)
                goto err_module_put;
 
+       if (ops->probe_finalize)
+               ops->probe_finalize(dev);
+
        return 0;
 
 err_module_put:
@@ -204,17 +241,31 @@ err_free_dev_param:
        return ret;
 }
 
+static void __iommu_release_device(struct device *dev)
+{
+       const struct iommu_ops *ops = dev->bus->iommu_ops;
+
+       iommu_device_unlink(dev->iommu->iommu_dev, dev);
+
+       iommu_group_remove_device(dev);
+
+       ops->release_device(dev);
+}
+
 void iommu_release_device(struct device *dev)
 {
        const struct iommu_ops *ops = dev->bus->iommu_ops;
 
-       if (dev->iommu_group)
+       if (!dev->iommu)
+               return;
+
+       if (ops->release_device)
+               __iommu_release_device(dev);
+       else if (dev->iommu_group)
                ops->remove_device(dev);
 
-       if (dev->iommu) {
-               module_put(ops->owner);
-               dev_iommu_free(dev);
-       }
+       module_put(ops->owner);
+       dev_iommu_free(dev);
 }
 
 static struct iommu_domain *__iommu_domain_alloc(struct bus_type *bus,

diff --git a/include/linux/iommu.h b/include/linux/iommu.h
index 1f027b0..30170d1 100644 (file)
--- a/include/linux/iommu.h
+++ b/include/linux/iommu.h
@@ -225,6 +225,10 @@ struct iommu_iotlb_gather {
  * @iova_to_phys: translate iova to physical address
  * @add_device: add device to iommu grouping
  * @remove_device: remove device from iommu grouping
+ * @probe_device: Add device to iommu driver handling
+ * @release_device: Remove device from iommu driver handling
+ * @probe_finalize: Do final setup work after the device is added to an IOMMU
+ *                  group and attached to the groups domain
  * @device_group: find iommu group for a particular device
  * @domain_get_attr: Query domain attributes
  * @domain_set_attr: Change domain attributes
@@ -275,6 +279,9 @@ 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);
+       struct iommu_device *(*probe_device)(struct device *dev);
+       void (*release_device)(struct device *dev);
+       void (*probe_finalize)(struct device *dev);
        struct iommu_group *(*device_group)(struct device *dev);
        int (*domain_get_attr)(struct iommu_domain *domain,
                               enum iommu_attr attr, void *data);
@@ -375,6 +382,7 @@ struct iommu_fault_param {
  *
  * @fault_param: IOMMU detected device fault reporting data
  * @fwspec:     IOMMU fwspec data
+ * @iommu_dev:  IOMMU device this device is linked to
  * @priv:       IOMMU Driver private data
  *
  * TODO: migrate other per device data pointers under iommu_dev_data, e.g.
@@ -384,6 +392,7 @@ struct dev_iommu {
        struct mutex lock;
        struct iommu_fault_param        *fault_param;
        struct iommu_fwspec             *fwspec;
+       struct iommu_device             *iommu_dev;
        void                            *priv;
 };