block migration: Report progress also via info migration

Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
diff --git a/block-migration.h b/block-migration.h
index a274d2d..ffa8ac0 100644
--- a/block-migration.h
+++ b/block-migration.h
@@ -15,5 +15,9 @@
 #define BLOCK_MIGRATION_H
 
 void blk_mig_init(void);
+int blk_mig_active(void);
+uint64_t blk_mig_bytes_transferred(void);
+uint64_t blk_mig_bytes_remaining(void);
+uint64_t blk_mig_bytes_total(void);
 
 #endif /* BLOCK_MIGRATION_H */