diff options
| -rw-r--r-- | drivers/vfio/vfio.c | 19 |
1 files changed, 11 insertions, 8 deletions
diff --git a/drivers/vfio/vfio.c b/drivers/vfio/vfio.c index 43d5622b19b7..13e0f39d91e0 100644 --- a/drivers/vfio/vfio.c +++ b/drivers/vfio/vfio.c @@ -274,6 +274,7 @@ static void vfio_group_release(struct kref *kref) { struct vfio_group *group = container_of(kref, struct vfio_group, kref); struct vfio_unbound_dev *unbound, *tmp; + struct iommu_group *iommu_group = group->iommu_group; WARN_ON(!list_empty(&group->device_list)); @@ -287,6 +288,7 @@ static void vfio_group_release(struct kref *kref) list_del(&group->vfio_next); vfio_free_group_minor(group->minor); vfio_group_unlock_and_free(group); + iommu_group_put(iommu_group); } static void vfio_group_put(struct vfio_group *group) @@ -625,6 +627,12 @@ int vfio_add_group_dev(struct device *dev, iommu_group_put(iommu_group); return PTR_ERR(group); } + } else { + /* + * A found vfio_group already holds a reference to the + * iommu_group. A created vfio_group keeps the reference. + */ + iommu_group_put(iommu_group); } device = vfio_group_get_device(group, dev); @@ -633,21 +641,19 @@ int vfio_add_group_dev(struct device *dev, dev_name(dev), iommu_group_id(iommu_group)); vfio_device_put(device); vfio_group_put(group); - iommu_group_put(iommu_group); return -EBUSY; } device = vfio_group_create_device(group, dev, ops, device_data); if (IS_ERR(device)) { vfio_group_put(group); - iommu_group_put(iommu_group); return PTR_ERR(device); } /* - * Added device holds reference to iommu_group and vfio_device - * (which in turn holds reference to vfio_group). Drop extra - * group reference used while acquiring device. + * Drop all but the vfio_device reference. The vfio_device holds + * a reference to the vfio_group, which holds a reference to the + * iommu_group. */ vfio_group_put(group); @@ -702,7 +708,6 @@ void *vfio_del_group_dev(struct device *dev) { struct vfio_device *device = dev_get_drvdata(dev); struct vfio_group *group = device->group; - struct iommu_group *iommu_group = group->iommu_group; void *device_data = device->device_data; struct vfio_unbound_dev *unbound; @@ -737,8 +742,6 @@ void *vfio_del_group_dev(struct device *dev) vfio_group_put(group); - iommu_group_put(iommu_group); - return device_data; } EXPORT_SYMBOL_GPL(vfio_del_group_dev); |