1 files changed, 14 insertions, 16 deletions

diff --git a/include/linux/backing-dev.h b/include/linux/backing-dev.h
index aee5f6ce166e..35b00746c712 100644
--- a/include/linux/backing-dev.h
+++ b/include/linux/backing-dev.h
@@ -31,6 +31,7 @@ enum bdi_state {
         BDI_async_congested,    /* The async (write) queue is getting full */
         BDI_sync_congested,     /* The sync queue is getting full */
         BDI_registered,         /* bdi_register() was done */
+        BDI_writeback_running,  /* Writeback is in progress */
         BDI_unused,             /* Available bits start here */
 };
 
@@ -45,22 +46,21 @@ enum bdi_stat_item {
 #define BDI_STAT_BATCH (8*(1+ilog2(nr_cpu_ids)))
 
 struct bdi_writeback {
-        struct list_head list;                  /* hangs off the bdi */
-
-        struct backing_dev_info *bdi;           /* our parent bdi */
+        struct backing_dev_info *bdi;   /* our parent bdi */
         unsigned int nr;
 
-        unsigned long last_old_flush;           /* last old data flush */
+        unsigned long last_old_flush;   /* last old data flush */
+        unsigned long last_active;      /* last time bdi thread was active */
 
-        struct task_struct      *task;          /* writeback task */
-        struct list_head        b_dirty;        /* dirty inodes */
-        struct list_head        b_io;           /* parked for writeback */
-        struct list_head        b_more_io;      /* parked for more writeback */
+        struct task_struct *task;       /* writeback thread */
+        struct timer_list wakeup_timer; /* used for delayed bdi thread wakeup */
+        struct list_head b_dirty;       /* dirty inodes */
+        struct list_head b_io;          /* parked for writeback */
+        struct list_head b_more_io;     /* parked for more writeback */
 };
 
 struct backing_dev_info {
         struct list_head bdi_list;
-        struct rcu_head rcu_head;
         unsigned long ra_pages; /* max readahead in PAGE_CACHE_SIZE units */
         unsigned long state;    /* Always use atomic bitops on this */
         unsigned int capabilities; /* Device capabilities */
@@ -80,10 +80,7 @@ struct backing_dev_info {
         unsigned int max_ratio, max_prop_frac;
 
         struct bdi_writeback wb;  /* default writeback info for this bdi */
-        spinlock_t wb_lock;       /* protects update side of wb_list */
-        struct list_head wb_list; /* the flusher threads hanging off this bdi */
-        unsigned long wb_mask;    /* bitmask of registered tasks */
-        unsigned int wb_cnt;      /* number of registered tasks */
+        spinlock_t wb_lock;       /* protects work_list */
 
         struct list_head work_list;
 
@@ -105,11 +102,12 @@ int bdi_register(struct backing_dev_info *bdi, struct device *parent,
 int bdi_register_dev(struct backing_dev_info *bdi, dev_t dev);
 void bdi_unregister(struct backing_dev_info *bdi);
 int bdi_setup_and_register(struct backing_dev_info *, char *, unsigned int);
-void bdi_start_writeback(struct backing_dev_info *bdi, struct super_block *sb,
-                                long nr_pages);
-int bdi_writeback_task(struct bdi_writeback *wb);
+void bdi_start_writeback(struct backing_dev_info *bdi, long nr_pages);
+void bdi_start_background_writeback(struct backing_dev_info *bdi);
+int bdi_writeback_thread(void *data);
 int bdi_has_dirty_io(struct backing_dev_info *bdi);
 void bdi_arm_supers_timer(void);
+void bdi_wakeup_thread_delayed(struct backing_dev_info *bdi);
 
 extern spinlock_t bdi_lock;
 extern struct list_head bdi_list;