Re: [PATCH v2 7/7] vfio: Remove vfio_free_device

[Anthony Krowiak <akrowiak@linux.ibm.com>]

Reviewed-by: Tony Krowiak <akrowiak@linux.ibm.com> : vfio_ap part

On 11/2/22 11:01 AM, Eric Farman wrote:
> With the "mess" sorted out, we should be able to inline the
> vfio_free_device call introduced by commit cb9ff3f3b84c
> ("vfio: Add helpers for unifying vfio_device life cycle")
> and remove them from driver release callbacks.
>
> Signed-off-by: Eric Farman <farman@linux.ibm.com>
> Reviewed-by: Jason Gunthorpe <jgg@nvidia.com>
> Reviewed-by: Kevin Tian <kevin.tian@intel.com>
> ---
>   drivers/gpu/drm/i915/gvt/kvmgt.c      |  1 -
>   drivers/s390/cio/vfio_ccw_ops.c       |  2 --
>   drivers/s390/crypto/vfio_ap_ops.c     |  6 ------
>   drivers/vfio/fsl-mc/vfio_fsl_mc.c     |  1 -
>   drivers/vfio/pci/vfio_pci_core.c      |  1 -
>   drivers/vfio/platform/vfio_amba.c     |  1 -
>   drivers/vfio/platform/vfio_platform.c |  1 -
>   drivers/vfio/vfio_main.c              | 22 ++++------------------
>   include/linux/vfio.h                  |  1 -
>   samples/vfio-mdev/mbochs.c            |  1 -
>   samples/vfio-mdev/mdpy.c              |  1 -
>   samples/vfio-mdev/mtty.c              |  1 -
>   12 files changed, 4 insertions(+), 35 deletions(-)
>
> diff --git a/drivers/gpu/drm/i915/gvt/kvmgt.c b/drivers/gpu/drm/i915/gvt/kvmgt.c
> index 7a45e5360caf..eee6805e67de 100644
> --- a/drivers/gpu/drm/i915/gvt/kvmgt.c
> +++ b/drivers/gpu/drm/i915/gvt/kvmgt.c
> @@ -1461,7 +1461,6 @@ static void intel_vgpu_release_dev(struct vfio_device *vfio_dev)
>   	struct intel_vgpu *vgpu = vfio_dev_to_vgpu(vfio_dev);
>   
>   	intel_gvt_destroy_vgpu(vgpu);
> -	vfio_free_device(vfio_dev);
>   }
>   
>   static const struct vfio_device_ops intel_vgpu_dev_ops = {
> diff --git a/drivers/s390/cio/vfio_ccw_ops.c b/drivers/s390/cio/vfio_ccw_ops.c
> index 1155f8bcedd9..598a3814d428 100644
> --- a/drivers/s390/cio/vfio_ccw_ops.c
> +++ b/drivers/s390/cio/vfio_ccw_ops.c
> @@ -143,8 +143,6 @@ static void vfio_ccw_mdev_release_dev(struct vfio_device *vdev)
>   	kmem_cache_free(vfio_ccw_io_region, private->io_region);
>   	kfree(private->cp.guest_cp);
>   	mutex_destroy(&private->io_mutex);
> -
> -	vfio_free_device(vdev);
>   }
>   
>   static void vfio_ccw_mdev_remove(struct mdev_device *mdev)
> diff --git a/drivers/s390/crypto/vfio_ap_ops.c b/drivers/s390/crypto/vfio_ap_ops.c
> index 0b4cc8c597ae..f108c0f14712 100644
> --- a/drivers/s390/crypto/vfio_ap_ops.c
> +++ b/drivers/s390/crypto/vfio_ap_ops.c
> @@ -765,11 +765,6 @@ static void vfio_ap_mdev_unlink_fr_queues(struct ap_matrix_mdev *matrix_mdev)
>   	}
>   }
>   
> -static void vfio_ap_mdev_release_dev(struct vfio_device *vdev)
> -{
> -	vfio_free_device(vdev);
> -}
> -
>   static void vfio_ap_mdev_remove(struct mdev_device *mdev)
>   {
>   	struct ap_matrix_mdev *matrix_mdev = dev_get_drvdata(&mdev->dev);
> @@ -1784,7 +1779,6 @@ static const struct attribute_group vfio_queue_attr_group = {
>   
>   static const struct vfio_device_ops vfio_ap_matrix_dev_ops = {
>   	.init = vfio_ap_mdev_init_dev,
> -	.release = vfio_ap_mdev_release_dev,
>   	.open_device = vfio_ap_mdev_open_device,
>   	.close_device = vfio_ap_mdev_close_device,
>   	.ioctl = vfio_ap_mdev_ioctl,
> diff --git a/drivers/vfio/fsl-mc/vfio_fsl_mc.c b/drivers/vfio/fsl-mc/vfio_fsl_mc.c
> index b16874e913e4..7b8889f55007 100644
> --- a/drivers/vfio/fsl-mc/vfio_fsl_mc.c
> +++ b/drivers/vfio/fsl-mc/vfio_fsl_mc.c
> @@ -568,7 +568,6 @@ static void vfio_fsl_mc_release_dev(struct vfio_device *core_vdev)
>   
>   	vfio_fsl_uninit_device(vdev);
>   	mutex_destroy(&vdev->igate);
> -	vfio_free_device(core_vdev);
>   }
>   
>   static int vfio_fsl_mc_remove(struct fsl_mc_device *mc_dev)
> diff --git a/drivers/vfio/pci/vfio_pci_core.c b/drivers/vfio/pci/vfio_pci_core.c
> index badc9d828cac..9be2d5be5d95 100644
> --- a/drivers/vfio/pci/vfio_pci_core.c
> +++ b/drivers/vfio/pci/vfio_pci_core.c
> @@ -2109,7 +2109,6 @@ void vfio_pci_core_release_dev(struct vfio_device *core_vdev)
>   	mutex_destroy(&vdev->vma_lock);
>   	kfree(vdev->region);
>   	kfree(vdev->pm_save);
> -	vfio_free_device(core_vdev);
>   }
>   EXPORT_SYMBOL_GPL(vfio_pci_core_release_dev);
>   
> diff --git a/drivers/vfio/platform/vfio_amba.c b/drivers/vfio/platform/vfio_amba.c
> index eaea63e5294c..18faf2678b99 100644
> --- a/drivers/vfio/platform/vfio_amba.c
> +++ b/drivers/vfio/platform/vfio_amba.c
> @@ -95,7 +95,6 @@ static void vfio_amba_release_dev(struct vfio_device *core_vdev)
>   
>   	vfio_platform_release_common(vdev);
>   	kfree(vdev->name);
> -	vfio_free_device(core_vdev);
>   }
>   
>   static void vfio_amba_remove(struct amba_device *adev)
> diff --git a/drivers/vfio/platform/vfio_platform.c b/drivers/vfio/platform/vfio_platform.c
> index 82cedcebfd90..9910451dc341 100644
> --- a/drivers/vfio/platform/vfio_platform.c
> +++ b/drivers/vfio/platform/vfio_platform.c
> @@ -83,7 +83,6 @@ static void vfio_platform_release_dev(struct vfio_device *core_vdev)
>   		container_of(core_vdev, struct vfio_platform_device, vdev);
>   
>   	vfio_platform_release_common(vdev);
> -	vfio_free_device(core_vdev);
>   }
>   
>   static int vfio_platform_remove(struct platform_device *pdev)
> diff --git a/drivers/vfio/vfio_main.c b/drivers/vfio/vfio_main.c
> index 2901b8ad5be9..9835757e2bee 100644
> --- a/drivers/vfio/vfio_main.c
> +++ b/drivers/vfio/vfio_main.c
> @@ -339,13 +339,10 @@ static void vfio_device_release(struct device *dev)
>   	vfio_release_device_set(device);
>   	ida_free(&vfio.device_ida, device->index);
>   
> -	/*
> -	 * kvfree() cannot be done here due to a life cycle mess in
> -	 * vfio-ccw. Before the ccw part is fixed all drivers are
> -	 * required to support @release and call vfio_free_device()
> -	 * from there.
> -	 */
> -	device->ops->release(device);
> +	if (device->ops->release)
> +		device->ops->release(device);
> +
> +	kvfree(device);
>   }
>   
>   static int vfio_init_device(struct vfio_device *device, struct device *dev,
> @@ -424,17 +421,6 @@ static int vfio_init_device(struct vfio_device *device, struct device *dev,
>   	return ret;
>   }
>   
> -/*
> - * The helper called by driver @release callback to free the device
> - * structure. Drivers which don't have private data to clean can
> - * simply use this helper as its @release.
> - */
> -void vfio_free_device(struct vfio_device *device)
> -{
> -	kvfree(device);
> -}
> -EXPORT_SYMBOL_GPL(vfio_free_device);
> -
>   static struct vfio_group *vfio_noiommu_group_alloc(struct device *dev,
>   		enum vfio_group_type type)
>   {
> diff --git a/include/linux/vfio.h b/include/linux/vfio.h
> index ba809268a48e..e7480154825e 100644
> --- a/include/linux/vfio.h
> +++ b/include/linux/vfio.h
> @@ -176,7 +176,6 @@ struct vfio_device *_vfio_alloc_device(size_t size, struct device *dev,
>   					dev, ops),				\
>   		     struct dev_struct, member)
>   
> -void vfio_free_device(struct vfio_device *device);
>   static inline void vfio_put_device(struct vfio_device *device)
>   {
>   	put_device(&device->device);
> diff --git a/samples/vfio-mdev/mbochs.c b/samples/vfio-mdev/mbochs.c
> index 117a8d799f71..8b5a3a778a25 100644
> --- a/samples/vfio-mdev/mbochs.c
> +++ b/samples/vfio-mdev/mbochs.c
> @@ -594,7 +594,6 @@ static void mbochs_release_dev(struct vfio_device *vdev)
>   	atomic_add(mdev_state->type->mbytes, &mbochs_avail_mbytes);
>   	kfree(mdev_state->pages);
>   	kfree(mdev_state->vconfig);
> -	vfio_free_device(vdev);
>   }
>   
>   static void mbochs_remove(struct mdev_device *mdev)
> diff --git a/samples/vfio-mdev/mdpy.c b/samples/vfio-mdev/mdpy.c
> index 946e8cfde6fd..721fb06c6413 100644
> --- a/samples/vfio-mdev/mdpy.c
> +++ b/samples/vfio-mdev/mdpy.c
> @@ -283,7 +283,6 @@ static void mdpy_release_dev(struct vfio_device *vdev)
>   
>   	vfree(mdev_state->memblk);
>   	kfree(mdev_state->vconfig);
> -	vfio_free_device(vdev);
>   }
>   
>   static void mdpy_remove(struct mdev_device *mdev)
> diff --git a/samples/vfio-mdev/mtty.c b/samples/vfio-mdev/mtty.c
> index e72085fc1376..3c2a421b9b69 100644
> --- a/samples/vfio-mdev/mtty.c
> +++ b/samples/vfio-mdev/mtty.c
> @@ -784,7 +784,6 @@ static void mtty_release_dev(struct vfio_device *vdev)
>   
>   	atomic_add(mdev_state->nr_ports, &mdev_avail_ports);
>   	kfree(mdev_state->vconfig);
> -	vfio_free_device(vdev);
>   }
>   
>   static void mtty_remove(struct mdev_device *mdev)