2 files changed, 8 insertions, 0 deletions

diff --git a/include/linux/backing-dev.h b/include/linux/backing-dev.h
index 469d56443c63..a008982e7c08 100644
--- a/include/linux/backing-dev.h
+++ b/include/linux/backing-dev.h
@@ -73,6 +73,11 @@ struct backing_dev_info {
 
         struct percpu_counter bdi_stat[NR_BDI_STAT_ITEMS];
 
+        unsigned long bw_time_stamp;    /* last time write bw is updated */
+        unsigned long written_stamp;    /* pages written at bw_time_stamp */
+        unsigned long write_bandwidth;  /* the estimated write bandwidth */
+        unsigned long avg_write_bandwidth; /* further smoothed write bw */
+
         struct prop_local_percpu completions;
         int dirty_exceeded;
 
diff --git a/include/linux/writeback.h b/include/linux/writeback.h
index df1b7f18f100..66862f2d90c8 100644
--- a/include/linux/writeback.h
+++ b/include/linux/writeback.h
@@ -118,6 +118,9 @@ void global_dirty_limits(unsigned long *pbackground, unsigned long *pdirty);
 unsigned long bdi_dirty_limit(struct backing_dev_info *bdi,
                                unsigned long dirty);
 
+void __bdi_update_bandwidth(struct backing_dev_info *bdi,
+                            unsigned long start_time);
+
 void page_writeback_init(void);
 void balance_dirty_pages_ratelimited_nr(struct address_space *mapping,
                                         unsigned long nr_pages_dirtied);