On Mon, Jul 14, 2014 at 02:48:59PM +1000, Dave Chinner wrote:
> From: Dave Chinner <dchinner@xxxxxxxxxx>
>
> When quota is on, it is expected that unused quota inodes have a
> value of NULLFSINO. The changes to support a separate project quota
> in 3.12 broken this rule for non-project quota inode enabled
> filesystem, as the code now refuses to write the group quota inode
> if neither group or project quotas are enabled. This regression was
> introduced by commit d892d58 ("xfs: Start using pquotaino from the
> superblock").
>
> In this case, we should be writing NULLFSINO rather than nothing to
> ensure that we leave the group quota inode in a valid state while
> quotas are enabled.
>
> Failure to do so doesn't cause a current kernel to break - the
> separate project quota inodes introduced translation code to always
> treat a zero inode as NULLFSINO. This was introduced by commit
> 0102629 ("xfs: Initialize all quota inodes to be NULLFSINO") with is
> also in 3.12 but older kernels do not do this and hence taking a
> filesystem back to an older kernel can result in quotas failing
> initialisation at mount time. When that happens, we see this in
> dmesg:
>
> [ 1649.215390] XFS (sdb): Mounting Filesystem
> [ 1649.316894] XFS (sdb): Failed to initialize disk quotas.
> [ 1649.316902] XFS (sdb): Ending clean mount
>
> By ensuring that we write NULLFSINO to quota inodes that aren't
> active, we avoid this problem. We have to be really careful when
> determining if the quota inodes are active or not, because we don't
> want to write a NULLFSINO if the quota inodes are active and we
> simply aren't updating them.
>
> Signed-off-by: Dave Chinner <dchinner@xxxxxxxxxx>
> ---
Reviewed-by: Brian Foster <bfoster@xxxxxxxxxx>
> fs/xfs/xfs_sb.c | 25 +++++++++++++++++++++----
> 1 file changed, 21 insertions(+), 4 deletions(-)
>
> diff --git a/fs/xfs/xfs_sb.c b/fs/xfs/xfs_sb.c
> index c3453b1..7703fa6 100644
> --- a/fs/xfs/xfs_sb.c
> +++ b/fs/xfs/xfs_sb.c
> @@ -483,10 +483,16 @@ xfs_sb_quota_to_disk(
> }
>
> /*
> - * GQUOTINO and PQUOTINO cannot be used together in versions
> - * of superblock that do not have pquotino. from->sb_flags
> - * tells us which quota is active and should be copied to
> - * disk.
> + * GQUOTINO and PQUOTINO cannot be used together in versions of
> + * superblock that do not have pquotino. from->sb_flags tells us which
> + * quota is active and should be copied to disk. If neither are active,
> + * make sure we write NULLFSINO to the sb_gquotino field as a quota
> + * inode value of "0" is invalid when the XFS_SB_VERSION_QUOTA feature
> + * bit is set.
> + *
> + * Note that we don't need to handle the sb_uquotino or sb_pquotino here
> + * as they do not require any translation. Hence the main sb field loop
> + * will write them appropriately from the in-core superblock.
> */
> if ((*fields & XFS_SB_GQUOTINO) &&
> (from->sb_qflags & XFS_GQUOTA_ACCT))
> @@ -494,6 +500,17 @@ xfs_sb_quota_to_disk(
> else if ((*fields & XFS_SB_PQUOTINO) &&
> (from->sb_qflags & XFS_PQUOTA_ACCT))
> to->sb_gquotino = cpu_to_be64(from->sb_pquotino);
> + else {
> + /*
> + * We can't rely on just the fields being logged to tell us
> + * that it is safe to write NULLFSINO - we should only do that
> + * if quotas are not actually enabled. Hence only write
> + * NULLFSINO if both in-core quota inodes are NULL.
> + */
> + if (from->sb_gquotino == NULLFSINO &&
> + from->sb_pquotino == NULLFSINO)
> + to->sb_gquotino = cpu_to_be64(NULLFSINO);
> + }
>
> *fields &= ~(XFS_SB_PQUOTINO | XFS_SB_GQUOTINO);
> }
> --
> 2.0.0
>
> _______________________________________________
> xfs mailing list
> xfs@xxxxxxxxxxx
> http://oss.sgi.com/mailman/listinfo/xfs
_______________________________________________
xfs mailing list
xfs@xxxxxxxxxxx
http://oss.sgi.com/mailman/listinfo/xfs
