[RFC v2 6/9] VFIO: Extend external user API

[Eric Auger]

On 09/11/2014 05:10 AM, Christoffer Dall wrote:
> On Mon, Sep 01, 2014 at 02:52:45PM +0200, Eric Auger wrote:
>> New functions are added to be called from ARM KVM-VFIO device.
> 
> This commit message seems somewhat random.  This patch doesn't deal with
> anything ARM specific, it introduces some generic functions that allows
> users external to vfio itself to retrieve information about a vfio
> platform device.

Yes you're right.
> 
>>
>> - vfio_device_get_external_user enables to get a vfio device from
>>   its fd
>> - vfio_device_put_external_user puts the vfio device
>> - vfio_external_base_device returns the struct device*,
>>   useful to access the platform_device
>>
>> Signed-off-by: Eric Auger <eric.auger at linaro.org>
>>
>> ---
>>
>> v1 -> v2:
>>
>> - vfio_external_get_base_device renamed into vfio_external_base_device
>> - vfio_external_get_type removed
>> ---
>>  drivers/vfio/vfio.c  | 24 ++++++++++++++++++++++++
>>  include/linux/vfio.h |  3 +++
>>  2 files changed, 27 insertions(+)
>>
>> diff --git a/drivers/vfio/vfio.c b/drivers/vfio/vfio.c
>> index 8e84471..282814e 100644
>> --- a/drivers/vfio/vfio.c
>> +++ b/drivers/vfio/vfio.c
>> @@ -1401,6 +1401,30 @@ void vfio_group_put_external_user(struct vfio_group *group)
>>  }
>>  EXPORT_SYMBOL_GPL(vfio_group_put_external_user);
>>  
>> +struct vfio_device *vfio_device_get_external_user(struct file *filep)
>> +{
>> +	struct vfio_device *vdev = filep->private_data;
>> +
>> +	if (filep->f_op != &vfio_device_fops)
>> +		return ERR_PTR(-EINVAL);
>> +
>> +	vfio_device_get(vdev);
>> +	return vdev;
>> +}
>> +EXPORT_SYMBOL_GPL(vfio_device_get_external_user);
>> +
>> +void vfio_device_put_external_user(struct vfio_device *vdev)
>> +{
>> +	vfio_device_put(vdev);
>> +}
>> +EXPORT_SYMBOL_GPL(vfio_device_put_external_user);
>> +
>> +struct device *vfio_external_base_device(struct vfio_device *vdev)
>> +{
>> +	return vdev->dev;
>> +}
>> +EXPORT_SYMBOL_GPL(vfio_external_base_device);
>> +
>>  int vfio_external_user_iommu_id(struct vfio_group *group)
>>  {
>>  	return iommu_group_id(group->iommu_group);
>> diff --git a/include/linux/vfio.h b/include/linux/vfio.h
>> index ffe04ed..bd4b6cb 100644
>> --- a/include/linux/vfio.h
>> +++ b/include/linux/vfio.h
>> @@ -99,6 +99,9 @@ extern void vfio_group_put_external_user(struct vfio_group *group);
>>  extern int vfio_external_user_iommu_id(struct vfio_group *group);
>>  extern long vfio_external_check_extension(struct vfio_group *group,
>>  					  unsigned long arg);
>> +extern struct vfio_device *vfio_device_get_external_user(struct file *filep);
>> +extern void vfio_device_put_external_user(struct vfio_device *vdev);
>> +extern struct device *vfio_external_base_device(struct vfio_device *vdev);
>>  
>>  struct pci_dev;
>>  #ifdef CONFIG_EEH
>> -- 
>> 1.9.1
>>
> Looks good to me,
> -Christoffer
>