xfs: repair refcount btrees
Reconstruct the refcount data from the rmap btree.
Link: https://docs.kernel.org/filesystems/xfs-online-fsck-design.html#case-study-rebuilding-the-space-reference-counts
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
diff --git a/fs/xfs/libxfs/xfs_refcount_btree.c b/fs/xfs/libxfs/xfs_refcount_btree.c
index 3fa795e..0d80bd9 100644
--- a/fs/xfs/libxfs/xfs_refcount_btree.c
+++ b/fs/xfs/libxfs/xfs_refcount_btree.c
@@ -226,7 +226,18 @@ xfs_refcountbt_verify(
level = be16_to_cpu(block->bb_level);
if (pag && xfs_perag_initialised_agf(pag)) {
- if (level >= pag->pagf_refcount_level)
+ unsigned int maxlevel = pag->pagf_refcount_level;
+
+#ifdef CONFIG_XFS_ONLINE_REPAIR
+ /*
+ * Online repair could be rewriting the refcount btree, so
+ * we'll validate against the larger of either tree while this
+ * is going on.
+ */
+ maxlevel = max_t(unsigned int, maxlevel,
+ pag->pagf_repair_refcount_level);
+#endif
+ if (level >= maxlevel)
return __this_address;
} else if (level >= mp->m_refc_maxlevels)
return __this_address;
