Re: [PATCH] ext4: report sub-block project quotas in statfs

[Jan Kara]

On Sun 01-11-26 12:58:47, Hungyu Lin wrote:
> ext4_statfs_project() converts the selected space limit from bytes to
> filesystem blocks before checking whether it is nonzero. A nonzero quota
> smaller than one block therefore skips the project space adjustments.
> 
> For example, a valid 1 KiB hard limit on a 4 KiB-block filesystem leaves
> statvfs() and df reporting the underlying filesystem's space, even when
> unprivileged data allocation fails with EDQUOT.
> 
> Test the byte limit before converting it to filesystem blocks. The
> resulting zero block limit then clamps the project space statistics to
> zero. Keep the existing rounding and the rule that a zero byte limit
> means no quota.
> 
> Fixes: 689c958cbe6b ("ext4: add project quota support")
> Signed-off-by: Hungyu Lin <dennylin0707@xxxxxxxxx>

Looks good. Feel free to add:

Reviewed-by: Jan Kara <jack@xxxxxxx>

								Honza

> ---
>  fs/ext4/super.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/fs/ext4/super.c b/fs/ext4/super.c
> index 9cae52471dee..91c1a54730f6 100644
> --- a/fs/ext4/super.c
> +++ b/fs/ext4/super.c
> @@ -7001,11 +7001,11 @@ static int ext4_statfs_project(struct super_block *sb,
>  
>  	limit = min_not_zero(dquot->dq_dqb.dqb_bsoftlimit,
>  			     dquot->dq_dqb.dqb_bhardlimit);
> -	limit >>= sb->s_blocksize_bits;
>  
>  	if (limit) {
>  		uint64_t	remaining = 0;
>  
> +		limit >>= sb->s_blocksize_bits;
>  		curblock = (dquot->dq_dqb.dqb_curspace +
>  			    dquot->dq_dqb.dqb_rsvspace) >> sb->s_blocksize_bits;
>  		if (limit > curblock)
> -- 
> 2.43.0
> 
-- 
Jan Kara <jack@xxxxxxxx>
SUSE Labs, CR