1 files changed, 14 insertions, 2 deletions

diff --git a/fs/fs-writeback.c b/fs/fs-writeback.c
index e2951506434d..f855916657ba 100644
--- a/fs/fs-writeback.c
+++ b/fs/fs-writeback.c
@@ -20,6 +20,7 @@
 #include <linux/sched.h>
 #include <linux/fs.h>
 #include <linux/mm.h>
+#include <linux/pagemap.h>
 #include <linux/kthread.h>
 #include <linux/freezer.h>
 #include <linux/writeback.h>
@@ -29,6 +30,11 @@
 #include "internal.h"
 
 /*
+ * 4MB minimal write chunk size
+ */
+#define MIN_WRITEBACK_PAGES     (4096UL >> (PAGE_CACHE_SHIFT - 10))
+
+/*
  * Passed into wb_writeback(), essentially a subset of writeback_control
  */
 struct wb_writeback_work {
@@ -742,11 +748,17 @@ static long wb_writeback(struct bdi_writeback *wb,
                 if (work->for_background && !over_bground_thresh(wb->bdi))
                         break;
 
+                /*
+                 * Kupdate and background works are special and we want to
+                 * include all inodes that need writing. Livelock avoidance is
+                 * handled by these works yielding to any other work so we are
+                 * safe.
+                 */
                 if (work->for_kupdate) {
                         oldest_jif = jiffies -
                                 msecs_to_jiffies(dirty_expire_interval * 10);
-                        work->older_than_this = &oldest_jif;
-                }
+                } else if (work->for_background)
+                        oldest_jif = jiffies;
 
                 trace_writeback_start(wb->bdi, work);
                 if (list_empty(&wb->b_io))