Re: [PATCH 5/7] xfs: switch xfs_get_defquota to take explicit type

[Christoph Hellwig <hch@infradead.org>]

On Wed, May 20, 2020 at 09:35:16PM -0500, Eric Sandeen wrote:
> xfs_get_defquota() currently takes an xfs_dquot, and from that obtains
> the type of default quota we should get (user/group/project).
> 
> But early in init, we don't have access to a fully set up quota, so
> that's not possible.  The next patch needs go set up default quota
> timers early, so switch xfs_get_defquota to take an explicit type
> and add a helper function to obtain that type from an xfs_dquot
> for the existing callers.
> 
> Signed-off-by: Eric Sandeen <sandeen@redhat.com>
> ---
>  fs/xfs/xfs_dquot.c       |  2 +-
>  fs/xfs/xfs_qm.c          |  2 +-
>  fs/xfs/xfs_qm.h          | 28 +++++++++++++++++++++++-----
>  fs/xfs/xfs_qm_syscalls.c |  2 +-
>  fs/xfs/xfs_trans_dquot.c |  2 +-
>  5 files changed, 27 insertions(+), 9 deletions(-)
> 
> diff --git a/fs/xfs/xfs_dquot.c b/fs/xfs/xfs_dquot.c
> index 714ecea..6196f7c 100644
> --- a/fs/xfs/xfs_dquot.c
> +++ b/fs/xfs/xfs_dquot.c
> @@ -75,7 +75,7 @@
>  	int			prealloc = 0;
>  
>  	ASSERT(d->d_id);
> -	defq = xfs_get_defquota(dq, q);
> +	defq = xfs_get_defquota(q, xfs_dquot_type(dq));
>  
>  	if (defq->bsoftlimit && !d->d_blk_softlimit) {
>  		d->d_blk_softlimit = cpu_to_be64(defq->bsoftlimit);
> diff --git a/fs/xfs/xfs_qm.c b/fs/xfs/xfs_qm.c
> index 6609b4b..ac0b5e7f 100644
> --- a/fs/xfs/xfs_qm.c
> +++ b/fs/xfs/xfs_qm.c
> @@ -558,7 +558,7 @@ struct xfs_qm_isolate {
>  		return;
>  
>  	ddqp = &dqp->q_core;
> -	defq = xfs_get_defquota(dqp, qinf);
> +	defq = xfs_get_defquota(qinf, xfs_dquot_type(dqp));
>  
>  	/*
>  	 * Timers and warnings have been already set, let's just set the
> diff --git a/fs/xfs/xfs_qm.h b/fs/xfs/xfs_qm.h
> index 3a85040..06df406 100644
> --- a/fs/xfs/xfs_qm.h
> +++ b/fs/xfs/xfs_qm.h
> @@ -113,6 +113,19 @@ struct xfs_quotainfo {
>  	return NULL;
>  }
>  
> +static inline int
> +xfs_dquot_type(struct xfs_dquot *dqp)
> +{
> +	if (XFS_QM_ISUDQ(dqp))
> +		return XFS_DQ_USER;
> +	else if (XFS_QM_ISGDQ(dqp))
> +		return XFS_DQ_GROUP;
> +	else {
> +		ASSERT(XFS_QM_ISPDQ(dqp));
> +		return XFS_DQ_PROJ;
> +	}

No real need for the elses here:

	if (XFS_QM_ISUDQ(dqp))
		return XFS_DQ_USER;
	if (XFS_QM_ISGDQ(dqp))
		return XFS_DQ_GROUP;
	ASSERT(XFS_QM_ISPDQ(dqp));
	return XFS_DQ_PROJ;

> +xfs_get_defquota(struct xfs_quotainfo *qi, int type)
>  {
>  	struct xfs_def_quota *defq;
>  
> +	switch (type) {
> +	case XFS_DQ_USER:
>  		defq = &qi->qi_usr_default;
> +		break;
> +	case XFS_DQ_GROUP:
>  		defq = &qi->qi_grp_default;
> +		break;
> +	case XFS_DQ_PROJ:
>  		defq = &qi->qi_prj_default;
> +		break;
> +	default:
> +		ASSERT(0);
>  	}
>  	return defq;

Just kill the defq variable and return directly?

	switch (type) {
	case XFS_DQ_USER:
 		return &qi->qi_usr_default;
	case XFS_DQ_GROUP:
  		return &qi->qi_grp_default;
	case XFS_DQ_PROJ:
  		return &qi->qi_prj_default;
	default:
		ASSERT(0);
		return NULL;
	}