Merge tag 'f2fs-for-3.9' of git://git.kernel.org/pub/scm/linux/kernel/git/jaegeuk...

[karo-tx-linux.git] / drivers / vfio / vfio.c

diff --git a/drivers/vfio/vfio.c b/drivers/vfio/vfio.c
index 56097c6d072d0797ecc9c13c9d2d231aa3e9afa8..28e2d5b2c0c759515ba733648c79aeef23ac05e9 100644 (file)
--- a/drivers/vfio/vfio.c
+++ b/drivers/vfio/vfio.c
@@ -191,6 +191,17 @@ static void vfio_container_put(struct vfio_container *container)
        kref_put(&container->kref, vfio_container_release);
 }
 
+static void vfio_group_unlock_and_free(struct vfio_group *group)
+{
+       mutex_unlock(&vfio.group_lock);
+       /*
+        * Unregister outside of lock.  A spurious callback is harmless now
+        * that the group is no longer in vfio.group_list.
+        */
+       iommu_group_unregister_notifier(group->iommu_group, &group->nb);
+       kfree(group);
+}
+
 /**
  * Group objects - create, release, get, put, search
  */
@@ -229,8 +240,7 @@ static struct vfio_group *vfio_create_group(struct iommu_group *iommu_group)
 
        minor = vfio_alloc_group_minor(group);
        if (minor < 0) {
-               mutex_unlock(&vfio.group_lock);
-               kfree(group);
+               vfio_group_unlock_and_free(group);
                return ERR_PTR(minor);
        }
 
@@ -239,8 +249,7 @@ static struct vfio_group *vfio_create_group(struct iommu_group *iommu_group)
                if (tmp->iommu_group == iommu_group) {
                        vfio_group_get(tmp);
                        vfio_free_group_minor(minor);
-                       mutex_unlock(&vfio.group_lock);
-                       kfree(group);
+                       vfio_group_unlock_and_free(group);
                        return tmp;
                }
        }
@@ -249,8 +258,7 @@ static struct vfio_group *vfio_create_group(struct iommu_group *iommu_group)
                            group, "%d", iommu_group_id(iommu_group));
        if (IS_ERR(dev)) {
                vfio_free_group_minor(minor);
-               mutex_unlock(&vfio.group_lock);
-               kfree(group);
+               vfio_group_unlock_and_free(group);
                return (struct vfio_group *)dev; /* ERR_PTR */
        }
 
@@ -274,16 +282,7 @@ static void vfio_group_release(struct kref *kref)
        device_destroy(vfio.class, MKDEV(MAJOR(vfio.devt), group->minor));
        list_del(&group->vfio_next);
        vfio_free_group_minor(group->minor);
-
-       mutex_unlock(&vfio.group_lock);
-
-       /*
-        * Unregister outside of lock.  A spurious callback is harmless now
-        * that the group is no longer in vfio.group_list.
-        */
-       iommu_group_unregister_notifier(group->iommu_group, &group->nb);
-
-       kfree(group);
+       vfio_group_unlock_and_free(group);
 }
 
 static void vfio_group_put(struct vfio_group *group)
@@ -443,7 +442,7 @@ static struct vfio_device *vfio_group_get_device(struct vfio_group *group,
  * a device.  It's not always practical to leave a device within a group
  * driverless as it could get re-bound to something unsafe.
  */
-static const char * const vfio_driver_whitelist[] = { "pci-stub" };
+static const char * const vfio_driver_whitelist[] = { "pci-stub", "pcieport" };
 
 static bool vfio_whitelisted_driver(struct device_driver *drv)
 {
@@ -466,8 +465,9 @@ static int vfio_dev_viable(struct device *dev, void *data)
 {
        struct vfio_group *group = data;
        struct vfio_device *device;
+       struct device_driver *drv = ACCESS_ONCE(dev->driver);
 
-       if (!dev->driver || vfio_whitelisted_driver(dev->driver))
+       if (!drv || vfio_whitelisted_driver(drv))
                return 0;
 
        device = vfio_group_get_device(group, dev);
@@ -642,33 +642,16 @@ int vfio_add_group_dev(struct device *dev,
 }
 EXPORT_SYMBOL_GPL(vfio_add_group_dev);
 
-/* Test whether a struct device is present in our tracking */
-static bool vfio_dev_present(struct device *dev)
+/* Given a referenced group, check if it contains the device */
+static bool vfio_dev_present(struct vfio_group *group, struct device *dev)
 {
-       struct iommu_group *iommu_group;
-       struct vfio_group *group;
        struct vfio_device *device;
 
-       iommu_group = iommu_group_get(dev);
-       if (!iommu_group)
-               return false;
-
-       group = vfio_group_get_from_iommu(iommu_group);
-       if (!group) {
-               iommu_group_put(iommu_group);
-               return false;
-       }
-
        device = vfio_group_get_device(group, dev);
-       if (!device) {
-               vfio_group_put(group);
-               iommu_group_put(iommu_group);
+       if (!device)
                return false;
-       }
 
        vfio_device_put(device);
-       vfio_group_put(group);
-       iommu_group_put(iommu_group);
        return true;
 }
 
@@ -682,10 +665,18 @@ void *vfio_del_group_dev(struct device *dev)
        struct iommu_group *iommu_group = group->iommu_group;
        void *device_data = device->device_data;
 
+       /*
+        * The group exists so long as we have a device reference.  Get
+        * a group reference and use it to scan for the device going away.
+        */
+       vfio_group_get(group);
+
        vfio_device_put(device);
 
        /* TODO send a signal to encourage this to be released */
-       wait_event(vfio.release_q, !vfio_dev_present(dev));
+       wait_event(vfio.release_q, !vfio_dev_present(group, dev));
+
+       vfio_group_put(group);
 
        iommu_group_put(iommu_group);