Re: [PATCH 03/11] xfs: refactor default quota grace period setting code

[Christoph Hellwig <hch@infradead.org>]

On Thu, Aug 20, 2020 at 07:11:47PM -0700, Darrick J. Wong wrote:
> From: Darrick J. Wong <darrick.wong@oracle.com>
> 
> Refactor the code that sets the default quota grace period into a helper
> function so that we can override the ondisk behavior later.
> 
> Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
> Reviewed-by: Amir Goldstein <amir73il@gmail.com>
> ---
>  fs/xfs/libxfs/xfs_format.h |   13 +++++++++++++
>  fs/xfs/xfs_dquot.c         |    9 +++++++++
>  fs/xfs/xfs_dquot.h         |    1 +
>  fs/xfs/xfs_ondisk.h        |    2 ++
>  fs/xfs/xfs_qm_syscalls.c   |    4 ++--
>  5 files changed, 27 insertions(+), 2 deletions(-)
> 
> 
> diff --git a/fs/xfs/libxfs/xfs_format.h b/fs/xfs/libxfs/xfs_format.h
> index ef36978239ac..e9e6248b35be 100644
> --- a/fs/xfs/libxfs/xfs_format.h
> +++ b/fs/xfs/libxfs/xfs_format.h
> @@ -1205,6 +1205,11 @@ static inline void xfs_dinode_put_rdev(struct xfs_dinode *dip, xfs_dev_t rdev)
>   * time zero is the Unix epoch, Jan  1 00:00:01 UTC 1970.  An expiration value
>   * of zero means that the quota limit has not been reached, and therefore no
>   * expiration has been set.
> + *
> + * The grace period for each quota type is stored in the root dquot (id = 0)
> + * and is applied to a non-root dquot when it exceeds the soft or hard limits.
> + * The length of quota grace periods are unsigned 32-bit quantities measured in
> + * units of seconds.  A value of zero means to use the default period.
>   */
>  
>  /*
> @@ -1219,6 +1224,14 @@ static inline void xfs_dinode_put_rdev(struct xfs_dinode *dip, xfs_dev_t rdev)
>   */
>  #define XFS_DQ_TIMEOUT_MAX	((int64_t)U32_MAX)
>  
> +/*
> + * Default quota grace periods, ranging from zero (use the compiled defaults)
> + * to ~136 years.  These are applied to a non-root dquot that has exceeded
> + * either limit.
> + */
> +#define XFS_DQ_GRACE_MIN	((int64_t)0)
> +#define XFS_DQ_GRACE_MAX	((int64_t)U32_MAX)
> +
>  /*
>   * This is the main portion of the on-disk representation of quota information
>   * for a user.  We pad this with some more expansion room to construct the on
> diff --git a/fs/xfs/xfs_dquot.c b/fs/xfs/xfs_dquot.c
> index 2425b1c30d11..ed3fa6ada0d3 100644
> --- a/fs/xfs/xfs_dquot.c
> +++ b/fs/xfs/xfs_dquot.c
> @@ -98,6 +98,15 @@ xfs_qm_adjust_dqlimits(
>  		xfs_dquot_set_prealloc_limits(dq);
>  }
>  
> +/* Set the length of the default grace period. */
> +void
> +xfs_dquot_set_grace_period(
> +	time64_t		*timer,
> +	time64_t		value)
> +{
> +	*timer = clamp_t(time64_t, value, XFS_DQ_GRACE_MIN, XFS_DQ_GRACE_MAX);
> +}

Why not return the value?