On Tue, Feb 09, 2021 at 12:20:29PM -0500, Brian Foster wrote:
> On Mon, Feb 08, 2021 at 08:10:38PM -0800, Darrick J. Wong wrote:
> > From: Darrick J. Wong <djwong@xxxxxxxxxx>
> >
> > Clear the needsrepair flag, since it's used to prevent mounting of an
> > inconsistent filesystem. We only do this if we make it to the end of
> > repair with a non-zero error code, and all the rebuilt indices and
> > corrected metadata are persisted correctly.
> >
> > Note that we cannot combine clearing needsrepair with clearing the quota
> > checked flags because we need to clear the quota flags even if
> > reformatting the log fails, whereas we can't clear needsrepair if the
> > log reformat fails.
> >
> > Signed-off-by: Darrick J. Wong <djwong@xxxxxxxxxx>
> > ---
> > include/xfs_mount.h | 1 +
> > libxfs/init.c | 25 +++++++++++++------------
> > repair/agheader.c | 21 +++++++++++++++++++++
> > repair/xfs_repair.c | 45 +++++++++++++++++++++++++++++++++++++++++++++
> > 4 files changed, 80 insertions(+), 12 deletions(-)
> >
> >
> ...
> > diff --git a/libxfs/init.c b/libxfs/init.c
> > index 9fe13b8d..98057b78 100644
> > --- a/libxfs/init.c
> > +++ b/libxfs/init.c
> > @@ -867,25 +867,17 @@ _("%s: Flushing the %s failed, err=%d!\n"),
> > }
> >
> > /*
> > - * Flush all dirty buffers to stable storage and report on writes that didn't
> > - * make it to stable storage.
> > + * Persist all disk write caches and report on writes that didn't make it to
> > + * stable storage. Callers should flush (or purge) the libxfs buffer caches
> > + * before calling this function.
> > */
> > -static int
> > +int
> > libxfs_flush_mount(
> > struct xfs_mount *mp)
> > {
> > int error = 0;
> > int err2;
> >
> > - /*
> > - * Purge the buffer cache to write all dirty buffers to disk and free
> > - * all incore buffers. Buffers that fail write verification will cause
> > - * the CORRUPT_WRITE flag to be set in the buftarg. Buffers that
> > - * cannot be written will cause the LOST_WRITE flag to be set in the
> > - * buftarg.
> > - */
> > - libxfs_bcache_purge();
> > -
>
> FWIW, my comment on the previous version was that I think it's
> reasonable to call libxfs_bcache_flush() here instead of the purge so
> callers don't necessarily have to do anything special. The one caller
> that does the purge is free to do so before calling
> libxfs_flush_mount(), as that essentially supercedes the flush that
> would otherwise occur here. Either way, the patch looks fine to me:
Ah, yeah. That's a pretty simple change to make. Thanks for the
review.
--D
> Reviewed-by: Brian Foster <bfoster@xxxxxxxxxx>
>
> > /* Flush all kernel and disk write caches, and report failures. */
> > if (mp->m_ddev_targp) {
> > err2 = libxfs_flush_buftarg(mp->m_ddev_targp, _("data device"));
> > @@ -923,6 +915,15 @@ libxfs_umount(
> >
> > libxfs_rtmount_destroy(mp);
> >
> > + /*
> > + * Purge the buffer cache to write all dirty buffers to disk and free
> > + * all incore buffers. Buffers that fail write verification will cause
> > + * the CORRUPT_WRITE flag to be set in the buftarg. Buffers that
> > + * cannot be written will cause the LOST_WRITE flag to be set in the
> > + * buftarg. Once that's done, instruct the disks to persist their
> > + * write caches.
> > + */
> > + libxfs_bcache_purge();
> > error = libxfs_flush_mount(mp);
> >
> > for (agno = 0; agno < mp->m_maxagi; agno++) {
> > diff --git a/repair/agheader.c b/repair/agheader.c
> > index 8bb99489..2af24106 100644
> > --- a/repair/agheader.c
> > +++ b/repair/agheader.c
> > @@ -452,6 +452,27 @@ secondary_sb_whack(
> > rval |= XR_AG_SB_SEC;
> > }
> >
> > + if (xfs_sb_version_needsrepair(sb)) {
> > + if (i == 0) {
> > + if (!no_modify)
> > + do_warn(
> > + _("clearing needsrepair flag and regenerating metadata\n"));
> > + else
> > + do_warn(
> > + _("would clear needsrepair flag and regenerate metadata\n"));
> > + } else {
> > + /*
> > + * Quietly clear needsrepair on the secondary supers as
> > + * part of ensuring them. If needsrepair is set on the
> > + * primary, it will be cleared at the end of repair
> > + * once we've flushed all other dirty blocks to disk.
> > + */
> > + sb->sb_features_incompat &=
> > + ~XFS_SB_FEAT_INCOMPAT_NEEDSREPAIR;
> > + rval |= XR_AG_SB_SEC;
> > + }
> > + }
> > +
> > return(rval);
> > }
> >
> > diff --git a/repair/xfs_repair.c b/repair/xfs_repair.c
> > index 32755821..f607afcb 100644
> > --- a/repair/xfs_repair.c
> > +++ b/repair/xfs_repair.c
> > @@ -712,6 +712,48 @@ check_fs_vs_host_sectsize(
> > }
> > }
> >
> > +/* Clear needsrepair after a successful repair run. */
> > +void
> > +clear_needsrepair(
> > + struct xfs_mount *mp)
> > +{
> > + struct xfs_buf *bp;
> > + int error;
> > +
> > + /*
> > + * If we're going to clear NEEDSREPAIR, we need to make absolutely sure
> > + * that everything is ok with the ondisk filesystem. At this point
> > + * we've flushed the filesystem metadata out of the buffer cache and
> > + * possibly rewrote the log, but we haven't forced the disks to persist
> > + * the writes to stable storage. Do that now, and if anything goes
> > + * wrong, leave NEEDSREPAIR in place. Don't purge the buffer cache
> > + * here since we're not done yet.
> > + */
> > + libxfs_bcache_flush();
> > + error = -libxfs_flush_mount(mp);
> > + if (error) {
> > + do_warn(
> > + _("Cannot clear needsrepair due to flush failure, err=%d.\n"),
> > + error);
> > + return;
> > + }
> > +
> > + /* Clear needsrepair from the superblock. */
> > + bp = libxfs_getsb(mp);
> > + if (!bp || bp->b_error) {
> > + do_warn(
> > + _("Cannot clear needsrepair from primary super, err=%d.\n"),
> > + bp ? bp->b_error : ENOMEM);
> > + } else {
> > + mp->m_sb.sb_features_incompat &=
> > + ~XFS_SB_FEAT_INCOMPAT_NEEDSREPAIR;
> > + libxfs_sb_to_disk(bp->b_addr, &mp->m_sb);
> > + libxfs_buf_mark_dirty(bp);
> > + }
> > + if (bp)
> > + libxfs_buf_relse(bp);
> > +}
> > +
> > int
> > main(int argc, char **argv)
> > {
> > @@ -1131,6 +1173,9 @@ _("Note - stripe unit (%d) and width (%d) were copied from a backup superblock.\
> > libxfs_bcache_flush();
> > format_log_max_lsn(mp);
> >
> > + if (xfs_sb_version_needsrepair(&mp->m_sb))
> > + clear_needsrepair(mp);
> > +
> > /* Report failure if anything failed to get written to our fs. */
> > error = -libxfs_umount(mp);
> > if (error)
> >
>
