Re: [PATCH 4.5/6] xfs: switch xfs_get_defquota to take explicit type

["Darrick J. Wong" <darrick.wong@oracle.com>]

On Wed, May 20, 2020 at 01:41:25PM -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, and
> so we will fail to set these defaults.
> 
> 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.

Ah, so this patch isn't itself fixing anything, it's preparing code for
something that happens in the next patch.

> Signed-off-by: Eric Sandeen <sandeen@redhat.com>
> ---
> 
> diff --git a/fs/xfs/xfs_dquot.c b/fs/xfs/xfs_dquot.c
> index 6d6afc0297b3..fdeaccc67d91 100644
> --- a/fs/xfs/xfs_dquot.c
> +++ b/fs/xfs/xfs_dquot.c
> @@ -75,7 +75,7 @@ xfs_qm_adjust_dqlimits(
>  	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 e97a3802939c..64ba943e0675 100644
> --- a/fs/xfs/xfs_qm.c
> +++ b/fs/xfs/xfs_qm.c
> @@ -558,7 +558,7 @@ xfs_qm_set_defquota(
>  		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 3a850401b102..06df406fdf72 100644
> --- a/fs/xfs/xfs_qm.h
> +++ b/fs/xfs/xfs_qm.h
> @@ -113,6 +113,19 @@ xfs_quota_inode(xfs_mount_t *mp, uint dq_flags)
>  	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;

/me suspects this could be tidier, e.g.

if (UDQ)
	return XFS_DQ_USER;
if (GDQ)
	return XFS_DQ_GROUP;
ASSERT(PDQ);
return XFS_DQ_PROJ;

Otherwise the rest looks ok.

--D


> +	}
> +}
> +
>  extern void	xfs_trans_mod_dquot(struct xfs_trans *tp, struct xfs_dquot *dqp,
>  				    uint field, int64_t delta);
>  extern void	xfs_trans_dqjoin(struct xfs_trans *, struct xfs_dquot *);
> @@ -164,17 +177,22 @@ extern int		xfs_qm_scall_quotaon(struct xfs_mount *, uint);
>  extern int		xfs_qm_scall_quotaoff(struct xfs_mount *, uint);
>  
>  static inline struct xfs_def_quota *
> -xfs_get_defquota(struct xfs_dquot *dqp, struct xfs_quotainfo *qi)
> +xfs_get_defquota(struct xfs_quotainfo *qi, int type)
>  {
>  	struct xfs_def_quota *defq;
>  
> -	if (XFS_QM_ISUDQ(dqp))
> +	switch (type) {
> +	case XFS_DQ_USER:
>  		defq = &qi->qi_usr_default;
> -	else if (XFS_QM_ISGDQ(dqp))
> +		break;
> +	case XFS_DQ_GROUP:
>  		defq = &qi->qi_grp_default;
> -	else {
> -		ASSERT(XFS_QM_ISPDQ(dqp));
> +		break;
> +	case XFS_DQ_PROJ:
>  		defq = &qi->qi_prj_default;
> +		break;
> +	default:
> +		ASSERT(0);
>  	}
>  	return defq;
>  }
> diff --git a/fs/xfs/xfs_qm_syscalls.c b/fs/xfs/xfs_qm_syscalls.c
> index 301a284ee4f9..13196d07c84e 100644
> --- a/fs/xfs/xfs_qm_syscalls.c
> +++ b/fs/xfs/xfs_qm_syscalls.c
> @@ -479,7 +479,7 @@ xfs_qm_scall_setqlim(
>  		goto out_unlock;
>  	}
>  
> -	defq = xfs_get_defquota(dqp, q);
> +	defq = xfs_get_defquota(q, xfs_dquot_type(dqp));
>  	xfs_dqunlock(dqp);
>  
>  	error = xfs_trans_alloc(mp, &M_RES(mp)->tr_qm_setqlim, 0, 0, 0, &tp);
> diff --git a/fs/xfs/xfs_trans_dquot.c b/fs/xfs/xfs_trans_dquot.c
> index 20542076e32a..edde366ca8e9 100644
> --- a/fs/xfs/xfs_trans_dquot.c
> +++ b/fs/xfs/xfs_trans_dquot.c
> @@ -591,7 +591,7 @@ xfs_trans_dqresv(
>  
>  	xfs_dqlock(dqp);
>  
> -	defq = xfs_get_defquota(dqp, q);
> +	defq = xfs_get_defquota(q, xfs_dquot_type(dqp));
>  
>  	if (flags & XFS_TRANS_DQ_RES_BLKS) {
>  		hardlimit = be64_to_cpu(dqp->q_core.d_blk_hardlimit);
>