diff --git a/include/linux/backing-dev.h b/include/linux/backing-dev.h
index f7a1390..7011d625 100644
--- a/include/linux/backing-dev.h
+++ b/include/linux/backing-dev.h
@@ -10,6 +10,8 @@
 
 #include <asm/atomic.h>
 
+struct page;
+
 /*
  * Bits in backing_dev_info.state
  */
@@ -88,6 +90,11 @@
 				  (1 << BDI_write_congested));
 }
 
+void clear_bdi_congested(struct backing_dev_info *bdi, int rw);
+void set_bdi_congested(struct backing_dev_info *bdi, int rw);
+long congestion_wait(int rw, long timeout);
+void congestion_end(int rw);
+
 #define bdi_cap_writeback_dirty(bdi) \
 	(!((bdi)->capabilities & BDI_CAP_NO_WRITEBACK))