v4.19.13 snapshot.
diff --git a/fs/xfs/scrub/btree.h b/fs/xfs/scrub/btree.h
new file mode 100644
index 0000000..aada763
--- /dev/null
+++ b/fs/xfs/scrub/btree.h
@@ -0,0 +1,51 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * Copyright (C) 2017 Oracle. All Rights Reserved.
+ * Author: Darrick J. Wong <darrick.wong@oracle.com>
+ */
+#ifndef __XFS_SCRUB_BTREE_H__
+#define __XFS_SCRUB_BTREE_H__
+
+/* btree scrub */
+
+/* Check for btree operation errors. */
+bool xchk_btree_process_error(struct xfs_scrub *sc,
+ struct xfs_btree_cur *cur, int level, int *error);
+
+/* Check for btree xref operation errors. */
+bool xchk_btree_xref_process_error(struct xfs_scrub *sc,
+ struct xfs_btree_cur *cur, int level, int *error);
+
+/* Check for btree corruption. */
+void xchk_btree_set_corrupt(struct xfs_scrub *sc,
+ struct xfs_btree_cur *cur, int level);
+
+/* Check for btree xref discrepancies. */
+void xchk_btree_xref_set_corrupt(struct xfs_scrub *sc,
+ struct xfs_btree_cur *cur, int level);
+
+struct xchk_btree;
+typedef int (*xchk_btree_rec_fn)(
+ struct xchk_btree *bs,
+ union xfs_btree_rec *rec);
+
+struct xchk_btree {
+ /* caller-provided scrub state */
+ struct xfs_scrub *sc;
+ struct xfs_btree_cur *cur;
+ xchk_btree_rec_fn scrub_rec;
+ struct xfs_owner_info *oinfo;
+ void *private;
+
+ /* internal scrub state */
+ union xfs_btree_rec lastrec;
+ bool firstrec;
+ union xfs_btree_key lastkey[XFS_BTREE_MAXLEVELS];
+ bool firstkey[XFS_BTREE_MAXLEVELS];
+ struct list_head to_check;
+};
+int xchk_btree(struct xfs_scrub *sc, struct xfs_btree_cur *cur,
+ xchk_btree_rec_fn scrub_fn, struct xfs_owner_info *oinfo,
+ void *private);
+
+#endif /* __XFS_SCRUB_BTREE_H__ */