Re: [PATCH v4 03/10] vfio/fsl-mc: Implement VFIO_DEVICE_GET_INFO ioctl

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

Hi Diana,

On 8/26/20 11:33 AM, Diana Craciun wrote:
> Allow userspace to get fsl-mc device info (number of regions
> and irqs).
> 
> Signed-off-by: Bharat Bhushan <Bharat.Bhushan@nxp.com>
> Signed-off-by: Diana Craciun <diana.craciun@oss.nxp.com>
Reviewed-by: Eric Auger <eric.auger@redhat.com>

Thanks

Eric
> ---
>  drivers/vfio/fsl-mc/vfio_fsl_mc.c | 21 ++++++++++++++++++++-
>  1 file changed, 20 insertions(+), 1 deletion(-)
> 
> diff --git a/drivers/vfio/fsl-mc/vfio_fsl_mc.c b/drivers/vfio/fsl-mc/vfio_fsl_mc.c
> index 85e007be3a5d..5a5460d01f00 100644
> --- a/drivers/vfio/fsl-mc/vfio_fsl_mc.c
> +++ b/drivers/vfio/fsl-mc/vfio_fsl_mc.c
> @@ -33,10 +33,29 @@ static void vfio_fsl_mc_release(void *device_data)
>  static long vfio_fsl_mc_ioctl(void *device_data, unsigned int cmd,
>  			      unsigned long arg)
>  {
> +	unsigned long minsz;
> +	struct vfio_fsl_mc_device *vdev = device_data;
> +	struct fsl_mc_device *mc_dev = vdev->mc_dev;
> +
>  	switch (cmd) {
>  	case VFIO_DEVICE_GET_INFO:
>  	{
> -		return -ENOTTY;
> +		struct vfio_device_info info;
> +
> +		minsz = offsetofend(struct vfio_device_info, num_irqs);
> +
> +		if (copy_from_user(&info, (void __user *)arg, minsz))
> +			return -EFAULT;
> +
> +		if (info.argsz < minsz)
> +			return -EINVAL;
> +
> +		info.flags = VFIO_DEVICE_FLAGS_FSL_MC;
> +		info.num_regions = mc_dev->obj_desc.region_count;
> +		info.num_irqs = mc_dev->obj_desc.irq_count;
> +
> +		return copy_to_user((void __user *)arg, &info, minsz) ?
> +			-EFAULT : 0;
>  	}
>  	case VFIO_DEVICE_GET_REGION_INFO:
>  	{
>