diff --git a/kmod/src/block.c b/kmod/src/block.c
index 8249a3d6..eb2c3b2e 100644
--- a/kmod/src/block.c
+++ b/kmod/src/block.c
@@ -802,6 +802,44 @@ void scoutfs_block_writer_forget(struct super_block *sb,
 	}
 }
 
+/*
+ * Change a cached block's location.  We're careful to only change its
+ * position in the rbtree.  If we find another block existing at the new
+ * location then we remove it from the cache and forget it if it was
+ * dirty.
+ */
+void scoutfs_block_move(struct super_block *sb,
+			struct scoutfs_block_writer *wri,
+			struct scoutfs_block *bl, u64 blkno)
+{
+	DECLARE_BLOCK_INFO(sb, binf);
+	struct block_private *bp = BLOCK_PRIVATE(bl);
+	struct block_private *existing = NULL;
+
+	spin_lock(&binf->lock);
+
+	existing = walk_block_rbtree(&binf->root, blkno, NULL);
+	if (existing) {
+		/* only nesting of binf and wri locks */
+		if (test_bit(BLOCK_BIT_DIRTY, &bp->bits)) {
+			spin_lock(&wri->lock);
+			if (test_bit(BLOCK_BIT_DIRTY, &bp->bits))
+				block_forget(sb, wri, bp);
+			spin_unlock(&wri->lock);
+		}
+		block_remove(sb, existing);
+	}
+
+	rb_erase(&bp->node, &binf->root);
+	RB_CLEAR_NODE(&bp->node);
+	bp->bl.blkno = blkno;
+	walk_block_rbtree(&binf->root, blkno, bp);
+
+	TRACE_BLOCK(move, bp);
+
+	spin_unlock(&binf->lock);
+}
+
 /*
  * The caller has ensured that no more dirtying will take place.  This
  * helps the caller avoid doing a bunch of work before calling into the
diff --git a/kmod/src/block.h b/kmod/src/block.h
index abcdd440..8a405f11 100644
--- a/kmod/src/block.h
+++ b/kmod/src/block.h
@@ -44,6 +44,9 @@ void scoutfs_block_writer_forget_all(struct super_block *sb,
 void scoutfs_block_writer_forget(struct super_block *sb,
 			         struct scoutfs_block_writer *wri,
 				 struct scoutfs_block *bl);
+void scoutfs_block_move(struct super_block *sb,
+			struct scoutfs_block_writer *wri,
+			struct scoutfs_block *bl, u64 blkno);
 bool scoutfs_block_writer_has_dirty(struct super_block *sb,
 				    struct scoutfs_block_writer *wri);
 u64 scoutfs_block_writer_dirty_bytes(struct super_block *sb,
diff --git a/kmod/src/scoutfs_trace.h b/kmod/src/scoutfs_trace.h
index 5f8db8a3..15fc7daa 100644
--- a/kmod/src/scoutfs_trace.h
+++ b/kmod/src/scoutfs_trace.h
@@ -2191,6 +2191,11 @@ DEFINE_EVENT(scoutfs_block_class, scoutfs_block_invalidate,
 		 int refcount, int io_count, unsigned long bits, u64 lru_moved),
 	TP_ARGS(sb, bp, blkno, refcount, io_count, bits, lru_moved)
 );
+DEFINE_EVENT(scoutfs_block_class, scoutfs_block_move,
+	TP_PROTO(struct super_block *sb, void *bp, u64 blkno,
+		 int refcount, int io_count, unsigned long bits, u64 lru_moved),
+	TP_ARGS(sb, bp, blkno, refcount, io_count, bits, lru_moved)
+);
 DEFINE_EVENT(scoutfs_block_class, scoutfs_block_mark_dirty,
 	TP_PROTO(struct super_block *sb, void *bp, u64 blkno,
 		 int refcount, int io_count, unsigned long bits, u64 lru_moved),