Re: [Qemu-devel] [PATCH v10 04/19] vfio: Common function to increment container_users

[Jike Song]

On 10/27/2016 05:29 AM, Kirti Wankhede wrote:
> This change rearrange functions to have common function to increment
> container_users
> 
> Signed-off-by: Kirti Wankhede <address@hidden>
> Signed-off-by: Neo Jia <address@hidden>
> Change-Id: I8bdeb352bc8439b107ffd519480fd4dc238677f2
> ---
>  drivers/vfio/vfio.c | 34 +++++++++++++++++++++-------------
>  1 file changed, 21 insertions(+), 13 deletions(-)
> 
> diff --git a/drivers/vfio/vfio.c b/drivers/vfio/vfio.c
> index 23bc86c1d05d..2e83bdf007fe 100644
> --- a/drivers/vfio/vfio.c
> +++ b/drivers/vfio/vfio.c
> @@ -1385,6 +1385,23 @@ static bool vfio_group_viable(struct vfio_group *group)
>                                        group, vfio_dev_viable) == 0);
>  }
>  
> +static int vfio_group_add_container_user(struct vfio_group *group)
> +{
> +     if (!atomic_inc_not_zero(&group->container_users))
> +             return -EINVAL;
> +
> +     if (group->noiommu) {
> +             atomic_dec(&group->container_users);
> +             return -EPERM;
> +     }

trivial: a blank line here

> +     if (!group->container->iommu_driver || !vfio_group_viable(group)) {
> +             atomic_dec(&group->container_users);
> +             return -EINVAL;
> +     }
> +
> +     return 0;
> +}
> +
>  static const struct file_operations vfio_device_fops;
>  
>  static int vfio_group_get_device_fd(struct vfio_group *group, char *buf)
> @@ -1694,23 +1711,14 @@ static const struct file_operations vfio_device_fops 
> = {
>  struct vfio_group *vfio_group_get_external_user(struct file *filep)
>  {
>       struct vfio_group *group = filep->private_data;
> +     int ret;
>  
>       if (filep->f_op != &vfio_group_fops)
>               return ERR_PTR(-EINVAL);
>  
> -     if (!atomic_inc_not_zero(&group->container_users))
> -             return ERR_PTR(-EINVAL);
> -
> -     if (group->noiommu) {
> -             atomic_dec(&group->container_users);
> -             return ERR_PTR(-EPERM);
> -     }
> -
> -     if (!group->container->iommu_driver ||
> -                     !vfio_group_viable(group)) {
> -             atomic_dec(&group->container_users);
> -             return ERR_PTR(-EINVAL);
> -     }
> +     ret = vfio_group_add_container_user(group);
> +     if (ret)
> +             return ERR_PTR(ret);
>  
>       vfio_group_get(group);
>  

Reviewed-by: Jike Song <address@hidden>

--
Thanks,
Jike