On Wed, Aug 26, 2009 at 12:46:12PM -0500, Alex Elder wrote:
> If you enable group or project quotas on an XFS file system, then the
> mount table presented through /proc/self/mounts erroneously shows
> that both options are in effect for the file system. The root of
> the problem is some bad logic in the xfs_showargs() function, which
> is used to format the file system type-specific options in effect
> for a file system.
>
> The problem originated in this GIT commit:
> Move platform specific mount option parse out of core XFS code
> Date: 11/22/07
> Author: Dave Chinner
> SHA1 ID: a67d7c5f5d25d0b13a4dfb182697135b014fa478
>
> For XFS quotas, project and group quota management are mutually
> exclusive--only one can be in effect at a time. There are two
> parts to managing quotas: aggregating usage information; and
> enforcing limits. It is possible to have a quota in effect
> (aggregating usage) but not enforced.
>
> These features are recorded on an XFS mount point using these flags:
> XFS_PQUOTA_ACCT - Project quotas are aggregated
> XFS_GQUOTA_ACCT - Group quotas are aggregated
> XFS_OQUOTA_ENFD - Project/group quotas are enforced
>
> The code in error is in fs/xfs/linux-2.6/xfs_super.c:
>
> if (mp->m_qflags & (XFS_PQUOTA_ACCT|XFS_OQUOTA_ENFD))
> seq_puts(m, "," MNTOPT_PRJQUOTA);
> else if (mp->m_qflags & XFS_PQUOTA_ACCT)
> seq_puts(m, "," MNTOPT_PQUOTANOENF);
>
> if (mp->m_qflags & (XFS_GQUOTA_ACCT|XFS_OQUOTA_ENFD))
> seq_puts(m, "," MNTOPT_GRPQUOTA);
> else if (mp->m_qflags & XFS_GQUOTA_ACCT)
> seq_puts(m, "," MNTOPT_GQUOTANOENF);
>
> The problem is that XFS_OQUOTA_ENFD will be set in mp->m_qflags
> if either group or project quotas are enforced, and as a result
> both MNTOPT_PRJQUOTA and MNTOPT_GRPQUOTA will be shown as mount
> options.
Indeed. Thanks for the detailed analysis.
Reviewed-by: Christoph Hellwig <hch@xxxxxx>
>
> Signed-off-by: Alex Elder <aelder@xxxxxxx>
>
> ---
> fs/xfs/linux-2.6/xfs_super.c | 20 ++++++++++++--------
> 1 file changed, 12 insertions(+), 8 deletions(-)
>
> Index: b/fs/xfs/linux-2.6/xfs_super.c
> ===================================================================
> --- a/fs/xfs/linux-2.6/xfs_super.c
> +++ b/fs/xfs/linux-2.6/xfs_super.c
> @@ -579,15 +579,19 @@ xfs_showargs(
> else if (mp->m_qflags & XFS_UQUOTA_ACCT)
> seq_puts(m, "," MNTOPT_UQUOTANOENF);
>
> - if (mp->m_qflags & (XFS_PQUOTA_ACCT|XFS_OQUOTA_ENFD))
> - seq_puts(m, "," MNTOPT_PRJQUOTA);
> - else if (mp->m_qflags & XFS_PQUOTA_ACCT)
> - seq_puts(m, "," MNTOPT_PQUOTANOENF);
> + /* Either project or group quotas can be active, not both */
>
> - if (mp->m_qflags & (XFS_GQUOTA_ACCT|XFS_OQUOTA_ENFD))
> - seq_puts(m, "," MNTOPT_GRPQUOTA);
> - else if (mp->m_qflags & XFS_GQUOTA_ACCT)
> - seq_puts(m, "," MNTOPT_GQUOTANOENF);
> + if (mp->m_qflags & XFS_PQUOTA_ACCT) {
> + if (mp->m_qflags & XFS_OQUOTA_ENFD)
> + seq_puts(m, "," MNTOPT_PRJQUOTA);
> + else
> + seq_puts(m, "," MNTOPT_PQUOTANOENF);
> + } else if (mp->m_qflags & XFS_GQUOTA_ACCT) {
> + if (mp->m_qflags & XFS_OQUOTA_ENFD)
> + seq_puts(m, "," MNTOPT_GRPQUOTA);
> + else
> + seq_puts(m, "," MNTOPT_GQUOTANOENF);
> + }
>
> if (!(mp->m_qflags & XFS_ALL_QUOTA_ACCT))
> seq_puts(m, "," MNTOPT_NOQUOTA);
>
> _______________________________________________
> xfs mailing list
> xfs@xxxxxxxxxxx
> http://oss.sgi.com/mailman/listinfo/xfs
---end quoted text---
|