Re: [PATCH 1/3] btrfs: define support masks for ioctl volume args v2

[Marcos Paulo de Souza <mpdesouza@suse.de>]

On Fri, 2020-02-21 at 14:02 +0100, David Sterba wrote:
> The ioctl data for devices or subvolumes can be passed via
> btrfs_ioctl_vol_args or btrfs_ioctl_vol_args_v2. The latter is more
> versatile and needs some caution as some of the flags make sense only
> for some ioctls.
> 
> As we're going to extend the flags, define support masks for each
> ioctl
> class separately.
> 
> Signed-off-by: David Sterba <dsterba@suse.com>
> ---
>  include/uapi/linux/btrfs.h | 16 +++++++++++++---
>  1 file changed, 13 insertions(+), 3 deletions(-)
> 
> diff --git a/include/uapi/linux/btrfs.h b/include/uapi/linux/btrfs.h
> index 7a8bc8b920f5..49ed71df5e94 100644
> --- a/include/uapi/linux/btrfs.h
> +++ b/include/uapi/linux/btrfs.h
> @@ -97,16 +97,26 @@ struct btrfs_ioctl_qgroup_limit_args {
>  };
>  
>  /*
> - * flags for subvolumes
> + * Arguments for specification of subvolumes or devices, supporting
> by-name or
> + * by-id and flags
>   *
> - * Used by:
> - * struct btrfs_ioctl_vol_args_v2.flags
> + * The set of supported flags depends on the ioctl
>   *
>   * BTRFS_SUBVOL_RDONLY is also provided/consumed by the following
> ioctls:
>   * - BTRFS_IOC_SUBVOL_GETFLAGS
>   * - BTRFS_IOC_SUBVOL_SETFLAGS
>   */
>  
> +/* Supported flags for BTRFS_IOC_RM_DEV_V2 */
> +#define BTRFS_DEVICE_REMOVE_ARGS_MASK				
> 	\
> +	(BTRFS_DEVICE_SPEC_BY_ID)
> +
> +/* Supported flags for BTRFS_IOC_SNAP_CREATE_V2 and
> BTRFS_IOC_SUBVOL_CREATE_V2 */
> +#define BTRFS_SUBVOL_CREATE_ARGS_MASK				
> 	\
> +	(BTRFS_SUBVOL_CREATE_ASYNC |					
> \
> +	 BTRFS_SUBVOL_RDONLY |						
> \
> +	 BTRFS_SUBVOL_QGROUP_INHERIT)
> +
>  struct btrfs_ioctl_vol_args_v2 {
>  	__s64 fd;
>  	__u64 transid;

Looks good to me,
Reviewed-by: Marcos Paulo de Souza <mpdesouza@suse.com>