1 files changed, 56 insertions, 1 deletions

diff --git a/include/linux/backing-dev.h b/include/linux/backing-dev.h
index 1d52425a6118..b449e738533a 100644
--- a/include/linux/backing-dev.h
+++ b/include/linux/backing-dev.h
@@ -13,6 +13,8 @@
 #include <linux/proportions.h>
 #include <linux/kernel.h>
 #include <linux/fs.h>
+#include <linux/sched.h>
+#include <linux/writeback.h>
 #include <asm/atomic.h>
 
 struct page;
@@ -23,9 +25,11 @@ struct dentry;
  * Bits in backing_dev_info.state
  */
 enum bdi_state {
-        BDI_pdflush,            /* A pdflush thread is working this device */
+        BDI_pending,            /* On its way to being activated */
+        BDI_wb_alloc,           /* Default embedded wb allocated */
         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_unused,             /* Available bits start here */
 };
 
@@ -39,7 +43,23 @@ 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 */
+        unsigned int nr;
+
+        unsigned long last_old_flush;           /* last old data flush */
+
+        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 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 */
@@ -48,6 +68,8 @@ struct backing_dev_info {
         void (*unplug_io_fn)(struct backing_dev_info *, struct page *);
         void *unplug_io_data;
 
+        char *name;
+
         struct percpu_counter bdi_stat[NR_BDI_STAT_ITEMS];
 
         struct prop_local_percpu completions;
@@ -56,6 +78,14 @@ struct backing_dev_info {
         unsigned int min_ratio;
         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 */
+
+        struct list_head work_list;
+
         struct device *dev;
 
 #ifdef CONFIG_DEBUG_FS
@@ -71,6 +101,20 @@ int bdi_register(struct backing_dev_info *bdi, struct device *parent,
                 const char *fmt, ...);
 int bdi_register_dev(struct backing_dev_info *bdi, dev_t dev);
 void bdi_unregister(struct backing_dev_info *bdi);
+void bdi_start_writeback(struct backing_dev_info *bdi, struct super_block *sb,
+                                long nr_pages);
+int bdi_writeback_task(struct bdi_writeback *wb);
+int bdi_has_dirty_io(struct backing_dev_info *bdi);
+
+extern spinlock_t bdi_lock;
+extern struct list_head bdi_list;
+
+static inline int wb_has_dirty_io(struct bdi_writeback *wb)
+{
+        return !list_empty(&wb->b_dirty) ||
+               !list_empty(&wb->b_io) ||
+               !list_empty(&wb->b_more_io);
+}
 
 static inline void __add_bdi_stat(struct backing_dev_info *bdi,
                 enum bdi_stat_item item, s64 amount)
@@ -261,6 +305,11 @@ static inline bool bdi_cap_swap_backed(struct backing_dev_info *bdi)
         return bdi->capabilities & BDI_CAP_SWAP_BACKED;
 }
 
+static inline bool bdi_cap_flush_forker(struct backing_dev_info *bdi)
+{
+        return bdi == &default_backing_dev_info;
+}
+
 static inline bool mapping_cap_writeback_dirty(struct address_space *mapping)
 {
         return bdi_cap_writeback_dirty(mapping->backing_dev_info);
@@ -276,4 +325,10 @@ static inline bool mapping_cap_swap_backed(struct address_space *mapping)
         return bdi_cap_swap_backed(mapping->backing_dev_info);
 }
 
+static inline int bdi_sched_wait(void *word)
+{
+        schedule();
+        return 0;
+}
+
 #endif          /* _LINUX_BACKING_DEV_H */