Re: [PATCH v2 11/15] vfio/platform: Use the new device life cycle helpers

[Eric Auger <eric.auger@redhat.com>]

Hi kevin,

On 9/1/22 16:37, Kevin Tian wrote:
> Move vfio_device_ops from platform core to platform drivers so device
> specific init/cleanup can be added.
>
> Introduce two new helpers vfio_platform_init/release_common() for the
> use in driver @init/@release.
>
> vfio_platform_probe/remove_common() will be deprecated.
>
> Signed-off-by: Kevin Tian <kevin.tian@intel.com>
> Reviewed-by: Jason Gunthorpe <jgg@nvidia.com>
> ---
>  drivers/vfio/platform/vfio_platform.c         | 66 +++++++++++++++----
>  drivers/vfio/platform/vfio_platform_common.c  | 53 ++++++++++++---
>  drivers/vfio/platform/vfio_platform_private.h | 15 +++++
>  3 files changed, 111 insertions(+), 23 deletions(-)
>
> diff --git a/drivers/vfio/platform/vfio_platform.c b/drivers/vfio/platform/vfio_platform.c
> index 04f40c5acfd6..82cedcebfd90 100644
> --- a/drivers/vfio/platform/vfio_platform.c
> +++ b/drivers/vfio/platform/vfio_platform.c
> @@ -7,6 +7,7 @@
>  #include <linux/module.h>
>  #include <linux/slab.h>
>  #include <linux/vfio.h>
> +#include <linux/pm_runtime.h>
>  #include <linux/platform_device.h>
>  
>  #include "vfio_platform_private.h"
> @@ -36,14 +37,11 @@ static int get_platform_irq(struct vfio_platform_device *vdev, int i)
>  	return platform_get_irq_optional(pdev, i);
>  }
>  
> -static int vfio_platform_probe(struct platform_device *pdev)
> +static int vfio_platform_init_dev(struct vfio_device *core_vdev)
>  {
> -	struct vfio_platform_device *vdev;
> -	int ret;
> -
> -	vdev = kzalloc(sizeof(*vdev), GFP_KERNEL);
> -	if (!vdev)
> -		return -ENOMEM;
> +	struct vfio_platform_device *vdev =
> +		container_of(core_vdev, struct vfio_platform_device, vdev);
> +	struct platform_device *pdev = to_platform_device(core_vdev->dev);
>  
>  	vdev->opaque = (void *) pdev;
>  	vdev->name = pdev->name;
> @@ -52,24 +50,64 @@ static int vfio_platform_probe(struct platform_device *pdev)
>  	vdev->get_irq = get_platform_irq;
>  	vdev->reset_required = reset_required;
>  
> -	ret = vfio_platform_probe_common(vdev, &pdev->dev);
> -	if (ret) {
> -		kfree(vdev);
> -		return ret;
> -	}
> +	return vfio_platform_init_common(vdev);
> +}
> +
> +static const struct vfio_device_ops vfio_platform_ops;
> +static int vfio_platform_probe(struct platform_device *pdev)
> +{
> +	struct vfio_platform_device *vdev;
> +	int ret;
> +
> +	vdev = vfio_alloc_device(vfio_platform_device, vdev, &pdev->dev,
> +				 &vfio_platform_ops);
> +	if (IS_ERR(vdev))
> +		return PTR_ERR(vdev);
> +
> +	ret = vfio_register_group_dev(&vdev->vdev);
> +	if (ret)
> +		goto out_put_vdev;
> +
> +	pm_runtime_enable(&pdev->dev);
>  	dev_set_drvdata(&pdev->dev, vdev);
>  	return 0;
> +
> +out_put_vdev:
> +	vfio_put_device(&vdev->vdev);
> +	return ret;
> +}
> +
> +static void vfio_platform_release_dev(struct vfio_device *core_vdev)
> +{
> +	struct vfio_platform_device *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)
>  {
>  	struct vfio_platform_device *vdev = dev_get_drvdata(&pdev->dev);
>  
> -	vfio_platform_remove_common(vdev);
> -	kfree(vdev);
> +	vfio_unregister_group_dev(&vdev->vdev);
> +	pm_runtime_disable(vdev->device);
> +	vfio_put_device(&vdev->vdev);
>  	return 0;
>  }
>  
> +static const struct vfio_device_ops vfio_platform_ops = {
> +	.name		= "vfio-platform",
> +	.init		= vfio_platform_init_dev,
> +	.release	= vfio_platform_release_dev,
> +	.open_device	= vfio_platform_open_device,
> +	.close_device	= vfio_platform_close_device,
> +	.ioctl		= vfio_platform_ioctl,
> +	.read		= vfio_platform_read,
> +	.write		= vfio_platform_write,
> +	.mmap		= vfio_platform_mmap,
> +};
> +
>  static struct platform_driver vfio_platform_driver = {
>  	.probe		= vfio_platform_probe,
>  	.remove		= vfio_platform_remove,
> diff --git a/drivers/vfio/platform/vfio_platform_common.c b/drivers/vfio/platform/vfio_platform_common.c
> index 256f55b84e70..4c01bf0adebb 100644
> --- a/drivers/vfio/platform/vfio_platform_common.c
> +++ b/drivers/vfio/platform/vfio_platform_common.c
> @@ -218,7 +218,7 @@ static int vfio_platform_call_reset(struct vfio_platform_device *vdev,
>  	return -EINVAL;
>  }
>  
> -static void vfio_platform_close_device(struct vfio_device *core_vdev)
> +void vfio_platform_close_device(struct vfio_device *core_vdev)
>  {
>  	struct vfio_platform_device *vdev =
>  		container_of(core_vdev, struct vfio_platform_device, vdev);
> @@ -236,8 +236,9 @@ static void vfio_platform_close_device(struct vfio_device *core_vdev)
>  	vfio_platform_regions_cleanup(vdev);
>  	vfio_platform_irq_cleanup(vdev);
>  }
> +EXPORT_SYMBOL_GPL(vfio_platform_close_device);
>  
> -static int vfio_platform_open_device(struct vfio_device *core_vdev)
> +int vfio_platform_open_device(struct vfio_device *core_vdev)
>  {
>  	struct vfio_platform_device *vdev =
>  		container_of(core_vdev, struct vfio_platform_device, vdev);
> @@ -273,9 +274,10 @@ static int vfio_platform_open_device(struct vfio_device *core_vdev)
>  	vfio_platform_regions_cleanup(vdev);
>  	return ret;
>  }
> +EXPORT_SYMBOL_GPL(vfio_platform_open_device);
>  
> -static long vfio_platform_ioctl(struct vfio_device *core_vdev,
> -				unsigned int cmd, unsigned long arg)
> +long vfio_platform_ioctl(struct vfio_device *core_vdev,
> +			 unsigned int cmd, unsigned long arg)
>  {
>  	struct vfio_platform_device *vdev =
>  		container_of(core_vdev, struct vfio_platform_device, vdev);
> @@ -382,6 +384,7 @@ static long vfio_platform_ioctl(struct vfio_device *core_vdev,
>  
>  	return -ENOTTY;
>  }
> +EXPORT_SYMBOL_GPL(vfio_platform_ioctl);
>  
>  static ssize_t vfio_platform_read_mmio(struct vfio_platform_region *reg,
>  				       char __user *buf, size_t count,
> @@ -438,8 +441,8 @@ static ssize_t vfio_platform_read_mmio(struct vfio_platform_region *reg,
>  	return -EFAULT;
>  }
>  
> -static ssize_t vfio_platform_read(struct vfio_device *core_vdev,
> -				  char __user *buf, size_t count, loff_t *ppos)
> +ssize_t vfio_platform_read(struct vfio_device *core_vdev,
> +			   char __user *buf, size_t count, loff_t *ppos)
>  {
>  	struct vfio_platform_device *vdev =
>  		container_of(core_vdev, struct vfio_platform_device, vdev);
> @@ -460,6 +463,7 @@ static ssize_t vfio_platform_read(struct vfio_device *core_vdev,
>  
>  	return -EINVAL;
>  }
> +EXPORT_SYMBOL_GPL(vfio_platform_read);
>  
>  static ssize_t vfio_platform_write_mmio(struct vfio_platform_region *reg,
>  					const char __user *buf, size_t count,
> @@ -515,8 +519,8 @@ static ssize_t vfio_platform_write_mmio(struct vfio_platform_region *reg,
>  	return -EFAULT;
>  }
>  
> -static ssize_t vfio_platform_write(struct vfio_device *core_vdev, const char __user *buf,
> -				   size_t count, loff_t *ppos)
> +ssize_t vfio_platform_write(struct vfio_device *core_vdev, const char __user *buf,
> +			    size_t count, loff_t *ppos)
>  {
>  	struct vfio_platform_device *vdev =
>  		container_of(core_vdev, struct vfio_platform_device, vdev);
> @@ -537,6 +541,7 @@ static ssize_t vfio_platform_write(struct vfio_device *core_vdev, const char __u
>  
>  	return -EINVAL;
>  }
> +EXPORT_SYMBOL_GPL(vfio_platform_write);
>  
>  static int vfio_platform_mmap_mmio(struct vfio_platform_region region,
>  				   struct vm_area_struct *vma)
> @@ -558,7 +563,7 @@ static int vfio_platform_mmap_mmio(struct vfio_platform_region region,
>  			       req_len, vma->vm_page_prot);
>  }
>  
> -static int vfio_platform_mmap(struct vfio_device *core_vdev, struct vm_area_struct *vma)
> +int vfio_platform_mmap(struct vfio_device *core_vdev, struct vm_area_struct *vma)
>  {
>  	struct vfio_platform_device *vdev =
>  		container_of(core_vdev, struct vfio_platform_device, vdev);
> @@ -598,6 +603,7 @@ static int vfio_platform_mmap(struct vfio_device *core_vdev, struct vm_area_stru
>  
>  	return -EINVAL;
>  }
> +EXPORT_SYMBOL_GPL(vfio_platform_mmap);
>  
>  static const struct vfio_device_ops vfio_platform_ops = {
>  	.name		= "vfio-platform",
> @@ -639,6 +645,35 @@ static int vfio_platform_of_probe(struct vfio_platform_device *vdev,
>   * If the firmware is ACPI type, then acpi_disabled is 0. All other checks are
>   * valid checks. We cannot claim that this system is DT.
>   */
> +int vfio_platform_init_common(struct vfio_platform_device *vdev)
> +{
> +	int ret;
> +	struct device *dev = vdev->vdev.dev;
> +
> +	ret = vfio_platform_acpi_probe(vdev, dev);
> +	if (ret)
> +		ret = vfio_platform_of_probe(vdev, dev);
> +
> +	if (ret)
> +		return ret;
> +
> +	vdev->device = dev;
> +	mutex_init(&vdev->igate);
> +
> +	ret = vfio_platform_get_reset(vdev);
> +	if (ret && vdev->reset_required)
> +		dev_err(dev, "No reset function found for device %s\n",
> +			vdev->name);
> +	return ret;
> +}
> +EXPORT_SYMBOL_GPL(vfio_platform_init_common);
> +
> +void vfio_platform_release_common(struct vfio_platform_device *vdev)
> +{
> +	vfio_platform_put_reset(vdev);
> +}
> +EXPORT_SYMBOL_GPL(vfio_platform_release_common);
> +
>  int vfio_platform_probe_common(struct vfio_platform_device *vdev,
>  			       struct device *dev)
>  {
> diff --git a/drivers/vfio/platform/vfio_platform_private.h b/drivers/vfio/platform/vfio_platform_private.h
> index 691b43f4b2b2..a769d649fb97 100644
> --- a/drivers/vfio/platform/vfio_platform_private.h
> +++ b/drivers/vfio/platform/vfio_platform_private.h
> @@ -81,6 +81,21 @@ struct vfio_platform_reset_node {
>  int vfio_platform_probe_common(struct vfio_platform_device *vdev,
>  			       struct device *dev);
>  void vfio_platform_remove_common(struct vfio_platform_device *vdev);
> +int vfio_platform_init_common(struct vfio_platform_device *vdev);
> +void vfio_platform_release_common(struct vfio_platform_device *vdev);
> +
> +int vfio_platform_open_device(struct vfio_device *core_vdev);
> +void vfio_platform_close_device(struct vfio_device *core_vdev);
> +long vfio_platform_ioctl(struct vfio_device *core_vdev,
> +			 unsigned int cmd, unsigned long arg);
> +ssize_t vfio_platform_read(struct vfio_device *core_vdev,
> +			   char __user *buf, size_t count,
> +			   loff_t *ppos);
> +ssize_t vfio_platform_write(struct vfio_device *core_vdev,
> +			    const char __user *buf,
> +			    size_t count, loff_t *ppos);
> +int vfio_platform_mmap(struct vfio_device *core_vdev,
> +		       struct vm_area_struct *vma);
>  
>  int vfio_platform_irq_init(struct vfio_platform_device *vdev);
>  void vfio_platform_irq_cleanup(struct vfio_platform_device *vdev);
Looks good to me. I also ran basic non regression testing

Reviewed-by: Eric Auger <eric.auger@redhat.com>
Tested-by: Eric Auger <eric.auger@redhat.com>

Eric