writeback: pay attention to wbc->nr_to_write in write_cache_pages
[safe/jmp/linux-2.6] / include / linux / writeback.h
index 4f4d98a..d63ef8f 100644 (file)
@@ -1,9 +1,12 @@
 /*
- * include/linux/writeback.h.
+ * include/linux/writeback.h
  */
 #ifndef WRITEBACK_H
 #define WRITEBACK_H
 
+#include <linux/sched.h>
+#include <linux/fs.h>
+
 struct backing_dev_info;
 
 extern spinlock_t inode_lock;
@@ -11,23 +14,11 @@ extern struct list_head inode_in_use;
 extern struct list_head inode_unused;
 
 /*
- * Yes, writeback.h requires sched.h
- * No, sched.h is not included from here.
- */
-static inline int task_is_pdflush(struct task_struct *task)
-{
-       return task->flags & PF_FLUSHER;
-}
-
-#define current_is_pdflush()   task_is_pdflush(current)
-
-/*
  * fs/fs-writeback.c
  */
 enum writeback_sync_modes {
        WB_SYNC_NONE,   /* Don't wait on anything */
        WB_SYNC_ALL,    /* Wait on every mapping */
-       WB_SYNC_HOLD,   /* Hold the inode on sb_dirty for sys_sync() */
 };
 
 /*
@@ -38,9 +29,14 @@ enum writeback_sync_modes {
 struct writeback_control {
        struct backing_dev_info *bdi;   /* If !NULL, only write back this
                                           queue */
+       struct super_block *sb;         /* if !NULL, only write inodes from
+                                          this super_block */
        enum writeback_sync_modes sync_mode;
        unsigned long *older_than_this; /* If !NULL, only write back inodes
                                           older than this */
+       unsigned long wb_start;         /* Time writeback_inodes_wb was
+                                          called. This is needed to avoid
+                                          extra jobs and livelock */
        long nr_to_write;               /* Write this many pages, and decrement
                                           this for each page written */
        long pages_skipped;             /* Pages which were not written */
@@ -56,50 +52,84 @@ struct writeback_control {
        unsigned nonblocking:1;         /* Don't get stuck on request queues */
        unsigned encountered_congestion:1; /* An output: a queue is full */
        unsigned for_kupdate:1;         /* A kupdate writeback */
+       unsigned for_background:1;      /* A background writeback */
        unsigned for_reclaim:1;         /* Invoked from the page allocator */
-       unsigned for_writepages:1;      /* This is a writepages() call */
        unsigned range_cyclic:1;        /* range_start is cyclic */
+       unsigned more_io:1;             /* more io to be dispatched */
 };
 
 /*
  * fs/fs-writeback.c
  */    
-void writeback_inodes(struct writeback_control *wbc);
-void wake_up_inode(struct inode *inode);
+struct bdi_writeback;
 int inode_wait(void *);
-void sync_inodes_sb(struct super_block *, int wait);
-void sync_inodes(int wait);
+void writeback_inodes_sb(struct super_block *);
+int writeback_inodes_sb_if_idle(struct super_block *);
+void sync_inodes_sb(struct super_block *);
+void writeback_inodes_wbc(struct writeback_control *wbc);
+long wb_do_writeback(struct bdi_writeback *wb, int force_wait);
+void wakeup_flusher_threads(long nr_pages);
 
 /* writeback.h requires fs.h; it, too, is not included from here. */
 static inline void wait_on_inode(struct inode *inode)
 {
        might_sleep();
-       wait_on_bit(&inode->i_state, __I_LOCK, inode_wait,
+       wait_on_bit(&inode->i_state, __I_NEW, inode_wait, TASK_UNINTERRUPTIBLE);
+}
+static inline void inode_sync_wait(struct inode *inode)
+{
+       might_sleep();
+       wait_on_bit(&inode->i_state, __I_SYNC, inode_wait,
                                                        TASK_UNINTERRUPTIBLE);
 }
 
+
 /*
  * mm/page-writeback.c
  */
-int wakeup_pdflush(long nr_pages);
-void laptop_io_completion(void);
+#ifdef CONFIG_BLOCK
+void laptop_io_completion(struct backing_dev_info *info);
 void laptop_sync_completion(void);
-void throttle_vm_writeout(void);
-void writeback_congestion_end(void);
+void laptop_mode_sync(struct work_struct *work);
+void laptop_mode_timer_fn(unsigned long data);
+#else
+static inline void laptop_sync_completion(void) { }
+#endif
+void throttle_vm_writeout(gfp_t gfp_mask);
 
 /* These are exported to sysctl. */
 extern int dirty_background_ratio;
+extern unsigned long dirty_background_bytes;
 extern int vm_dirty_ratio;
-extern int dirty_writeback_interval;
-extern int dirty_expire_interval;
+extern unsigned long vm_dirty_bytes;
+extern unsigned int dirty_writeback_interval;
+extern unsigned int dirty_expire_interval;
+extern int vm_highmem_is_dirtyable;
 extern int block_dump;
 extern int laptop_mode;
 
+extern unsigned long determine_dirtyable_memory(void);
+
+extern int dirty_background_ratio_handler(struct ctl_table *table, int write,
+               void __user *buffer, size_t *lenp,
+               loff_t *ppos);
+extern int dirty_background_bytes_handler(struct ctl_table *table, int write,
+               void __user *buffer, size_t *lenp,
+               loff_t *ppos);
+extern int dirty_ratio_handler(struct ctl_table *table, int write,
+               void __user *buffer, size_t *lenp,
+               loff_t *ppos);
+extern int dirty_bytes_handler(struct ctl_table *table, int write,
+               void __user *buffer, size_t *lenp,
+               loff_t *ppos);
+
 struct ctl_table;
-struct file;
-int dirty_writeback_centisecs_handler(struct ctl_table *, int, struct file *,
+int dirty_writeback_centisecs_handler(struct ctl_table *, int,
                                      void __user *, size_t *, loff_t *);
 
+void get_dirty_limits(unsigned long *pbackground, unsigned long *pdirty,
+                     unsigned long *pbdi_dirty, struct backing_dev_info *bdi);
+
 void page_writeback_init(void);
 void balance_dirty_pages_ratelimited_nr(struct address_space *mapping,
                                        unsigned long nr_pages_dirtied);
@@ -110,15 +140,16 @@ balance_dirty_pages_ratelimited(struct address_space *mapping)
        balance_dirty_pages_ratelimited_nr(mapping, 1);
 }
 
-int pdflush_operation(void (*fn)(unsigned long), unsigned long arg0);
-extern int generic_writepages(struct address_space *mapping,
-                             struct writeback_control *wbc);
+typedef int (*writepage_t)(struct page *page, struct writeback_control *wbc,
+                               void *data);
+
+int generic_writepages(struct address_space *mapping,
+                      struct writeback_control *wbc);
+int write_cache_pages(struct address_space *mapping,
+                     struct writeback_control *wbc, writepage_t writepage,
+                     void *data);
 int do_writepages(struct address_space *mapping, struct writeback_control *wbc);
-int sync_page_range(struct inode *inode, struct address_space *mapping,
-                       loff_t pos, loff_t count);
-int sync_page_range_nolock(struct inode *inode, struct address_space *mapping,
-                          loff_t pos, loff_t count);
-void set_page_dirty_balance(struct page *page);
+void set_page_dirty_balance(struct page *page, int page_mkwrite);
 void writeback_set_ratelimit(void);
 
 /* pdflush.c */