diff --git a/drivers/block/blkmap.c b/drivers/block/blkmap.c
index 14aa1e4d088..bd55bdf24b7 100644
--- a/drivers/block/blkmap.c
+++ b/drivers/block/blkmap.c
@@ -281,6 +281,9 @@ static ulong blkmap_blk_write_slice(struct blkmap *bm, struct blkmap_slice *bms,
 {
 	lbaint_t nr, cnt;
 
+	if (!bms->write)
+		return 0;
+
 	nr = blknr - bms->blknr;
 	cnt = (blkcnt < bms->blkcnt) ? blkcnt : bms->blkcnt;
 	return bms->write(bm, bms, nr, cnt, buffer);