On Thu, Jul 02, 2020 at 08:50:53AM +1000, Dave Chinner wrote:
> On Tue, Jun 30, 2020 at 08:42:16AM -0700, Darrick J. Wong wrote:
> > From: Darrick J. Wong <darrick.wong@xxxxxxxxxx>
> >
> > Use the incore dq_flags to figure out the dquot type. This is the first
> > step towards removing xfs_disk_dquot from the incore dquot.
> >
> > Signed-off-by: Darrick J. Wong <darrick.wong@xxxxxxxxxx>
> > ---
> > fs/xfs/libxfs/xfs_quota_defs.h | 2 ++
> > fs/xfs/scrub/quota.c | 4 ----
> > fs/xfs/xfs_dquot.c | 33 +++++++++++++++++++++++++++++++--
> > fs/xfs/xfs_dquot.h | 2 ++
> > fs/xfs/xfs_dquot_item.c | 6 ++++--
> > fs/xfs/xfs_qm.c | 4 ++--
> > fs/xfs/xfs_qm.h | 2 +-
> > fs/xfs/xfs_qm_syscalls.c | 9 +++------
> > 8 files changed, 45 insertions(+), 17 deletions(-)
> >
> >
> > diff --git a/fs/xfs/libxfs/xfs_quota_defs.h b/fs/xfs/libxfs/xfs_quota_defs.h
> > index 56d9dd787e7b..459023b0a304 100644
> > --- a/fs/xfs/libxfs/xfs_quota_defs.h
> > +++ b/fs/xfs/libxfs/xfs_quota_defs.h
> > @@ -29,6 +29,8 @@ typedef uint16_t xfs_qwarncnt_t;
> >
> > #define XFS_DQ_ALLTYPES (XFS_DQ_USER|XFS_DQ_PROJ|XFS_DQ_GROUP)
> >
> > +#define XFS_DQ_ONDISK (XFS_DQ_ALLTYPES)
>
> That's used as an on-disk flags mask. Perhaps XFS_DQF_ONDISK_MASK?
Well, based on Christoph's suggestions I broke the incore dquot flags
(XFS_DQ_*) apart from the ondisk dquot flags (XFS_DQFLAG_*). Not sure
if that's really better, but at least the namespaces are separate now.
> > +
> > #define XFS_DQ_FLAGS \
> > { XFS_DQ_USER, "USER" }, \
> > { XFS_DQ_PROJ, "PROJ" }, \
> > diff --git a/fs/xfs/scrub/quota.c b/fs/xfs/scrub/quota.c
> > index 905a34558361..710659d3fa28 100644
> > --- a/fs/xfs/scrub/quota.c
> > +++ b/fs/xfs/scrub/quota.c
> > @@ -108,10 +108,6 @@ xchk_quota_item(
> >
> > sqi->last_id = id;
> >
> > - /* Did we get the dquot type we wanted? */
> > - if (dqtype != (d->d_flags & XFS_DQ_ALLTYPES))
> > - xchk_fblock_set_corrupt(sc, XFS_DATA_FORK, offset);
> > -
> > if (d->d_pad0 != cpu_to_be32(0) || d->d_pad != cpu_to_be16(0))
> > xchk_fblock_set_corrupt(sc, XFS_DATA_FORK, offset);
> >
> > diff --git a/fs/xfs/xfs_dquot.c b/fs/xfs/xfs_dquot.c
> > index 46c8ca83c04d..59d1bce34a98 100644
> > --- a/fs/xfs/xfs_dquot.c
> > +++ b/fs/xfs/xfs_dquot.c
> > @@ -561,6 +561,16 @@ xfs_dquot_from_disk(
> > return 0;
> > }
> >
> > +/* Copy the in-core quota fields into the on-disk buffer. */
> > +void
> > +xfs_dquot_to_disk(
> > + struct xfs_disk_dquot *ddqp,
> > + struct xfs_dquot *dqp)
> > +{
> > + memcpy(ddqp, &dqp->q_core, sizeof(struct xfs_disk_dquot));
> > + ddqp->d_flags = dqp->dq_flags & XFS_DQ_ONDISK;
> > +}
> > +
> > /* Allocate and initialize the dquot buffer for this in-core dquot. */
> > static int
> > xfs_qm_dqread_alloc(
> > @@ -1108,6 +1118,17 @@ xfs_qm_dqflush_done(
> > xfs_dqfunlock(dqp);
> > }
> >
> > +/* Check incore dquot for errors before we flush. */
> > +static xfs_failaddr_t
> > +xfs_qm_dqflush_check(
> > + struct xfs_dquot *dqp)
> > +{
> > + if (hweight8(dqp->dq_flags & XFS_DQ_ALLTYPES) != 1)
> > + return __this_address;
>
> This only checks the low 8 bits in dq_flags, which is a 32 bit
> field. If we ever renumber the dq flags and the dquot types end up
> outside the LSB, this code will break.
>
> I don't really see a need to micro-optimise the code so much it
> leaves landmines like this in the code...
Ok. Fixed.
--D
> Cheers,
>
> Dave.
> --
> Dave Chinner
> david@xxxxxxxxxxxxx
