xfs_scrub: retry scrub (and repair) of items that are ok except for XFAIL

Sometimes a metadata object will pass all of the obvious scrubber
checks, but we won't be able to cross-reference the object's records
with other metadata objects (e.g. a file data fork and a free space
btree both claim ownership of an extent).  When this happens during the
checking phase, we should queue the object for a repair, which means
that phase 4 will keep re-evaluating the object as repairs proceed.
Eventually, the hope is that we'll fix the filesystem and everything
will scrub cleanly; if not, we recommend running xfs_repair as a second
attempt to fix the inconsistency.

Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Eric Sandeen <sandeen@redhat.com>
Signed-off-by: Eric Sandeen <sandeen@sandeen.net>

diff --git a/scrub/scrub.c b/scrub/scrub.c
index 07ae0673140b5a97b4575a5a907c13bed827ea66..4ef19656dcdb08210ab77e98eb26f78493c9d31e 100644 (file)
--- a/scrub/scrub.c
+++ b/scrub/scrub.c
@@ -223,6 +223,16 @@ _("Optimization is possible."));
                return CHECK_REPAIR;
        }
 
+       /*
+        * This metadata object itself looks ok, but we noticed inconsistencies
+        * when comparing it with the other filesystem metadata.  If we're in
+        * repair mode we need to queue it for a "repair" so that phase 4 will
+        * re-examine the object as repairs progress to see if the kernel will
+        * deem it completely consistent at some point.
+        */
+       if (xref_failed(meta) && ctx->mode == SCRUB_MODE_REPAIR)
+               return CHECK_REPAIR;
+
        /* Everything is ok. */
        return CHECK_DONE;
 }
@@ -787,6 +797,23 @@ _("Read-only filesystem; cannot make changes."));
                        return CHECK_RETRY;
                str_corrupt(ctx, descr_render(&dsc),
 _("Repair unsuccessful; offline repair required."));
+       } else if (xref_failed(&meta)) {
+               /*
+                * This metadata object itself looks ok, but we still noticed
+                * inconsistencies when comparing it with the other filesystem
+                * metadata.  If we're in "final warning" mode, advise the
+                * caller to run xfs_repair; otherwise, we'll keep trying to
+                * reverify the cross-referencing as repairs progress.
+                */
+               if (repair_flags & XRM_COMPLAIN_IF_UNFIXED) {
+                       str_info(ctx, descr_render(&dsc),
+ _("Seems correct but cross-referencing failed; offline repair recommended."));
+               } else {
+                       if (verbose)
+                               str_info(ctx, descr_render(&dsc),
+ _("Seems correct but cross-referencing failed; will keep checking."));
+                       return CHECK_RETRY;
+               }
        } else {
                /* Clean operation, no corruption detected. */
                if (needs_repair(&oldm))