2 * include/linux/writeback.h.
7 struct backing_dev_info;
9 extern spinlock_t inode_lock;
10 extern struct list_head inode_in_use;
11 extern struct list_head inode_unused;
14 * Yes, writeback.h requires sched.h
15 * No, sched.h is not included from here.
17 static inline int task_is_pdflush(struct task_struct *task)
19 return task->flags & PF_FLUSHER;
22 #define current_is_pdflush() task_is_pdflush(current)
27 enum writeback_sync_modes {
28 WB_SYNC_NONE, /* Don't wait on anything */
29 WB_SYNC_ALL, /* Wait on every mapping */
30 WB_SYNC_HOLD, /* Hold the inode on sb_dirty for sys_sync() */
34 * A control structure which tells the writeback code what to do. These are
35 * always on the stack, and hence need no locking. They are always initialised
36 * in a manner such that unspecified fields are set to zero.
38 struct writeback_control {
39 struct backing_dev_info *bdi; /* If !NULL, only write back this
41 enum writeback_sync_modes sync_mode;
42 unsigned long *older_than_this; /* If !NULL, only write back inodes
44 long nr_to_write; /* Write this many pages, and decrement
45 this for each page written */
46 long pages_skipped; /* Pages which were not written */
49 * For a_ops->writepages(): is start or end are non-zero then this is
50 * a hint that the filesystem need only write out the pages inside that
51 * byterange. The byte at `end' is included in the writeout request.
56 unsigned nonblocking:1; /* Don't get stuck on request queues */
57 unsigned encountered_congestion:1; /* An output: a queue is full */
58 unsigned for_kupdate:1; /* A kupdate writeback */
59 unsigned for_reclaim:1; /* Invoked from the page allocator */
60 unsigned for_writepages:1; /* This is a writepages() call */
61 unsigned range_cyclic:1; /* range_start is cyclic */
67 void writeback_inodes(struct writeback_control *wbc);
68 void wake_up_inode(struct inode *inode);
69 int inode_wait(void *);
70 void sync_inodes_sb(struct super_block *, int wait);
71 void sync_inodes(int wait);
73 /* writeback.h requires fs.h; it, too, is not included from here. */
74 static inline void wait_on_inode(struct inode *inode)
77 wait_on_bit(&inode->i_state, __I_LOCK, inode_wait,
78 TASK_UNINTERRUPTIBLE);
84 int wakeup_pdflush(long nr_pages);
85 void laptop_io_completion(void);
86 void laptop_sync_completion(void);
87 void throttle_vm_writeout(void);
88 void writeback_congestion_end(void);
90 /* These are exported to sysctl. */
91 extern int dirty_background_ratio;
92 extern int vm_dirty_ratio;
93 extern int dirty_writeback_interval;
94 extern int dirty_expire_interval;
95 extern int block_dump;
96 extern int laptop_mode;
100 int dirty_writeback_centisecs_handler(struct ctl_table *, int, struct file *,
101 void __user *, size_t *, loff_t *);
103 void page_writeback_init(void);
104 void balance_dirty_pages_ratelimited_nr(struct address_space *mapping,
105 unsigned long nr_pages_dirtied);
108 balance_dirty_pages_ratelimited(struct address_space *mapping)
110 balance_dirty_pages_ratelimited_nr(mapping, 1);
113 int pdflush_operation(void (*fn)(unsigned long), unsigned long arg0);
114 extern int generic_writepages(struct address_space *mapping,
115 struct writeback_control *wbc);
116 int do_writepages(struct address_space *mapping, struct writeback_control *wbc);
117 int sync_page_range(struct inode *inode, struct address_space *mapping,
118 loff_t pos, loff_t count);
119 int sync_page_range_nolock(struct inode *inode, struct address_space *mapping,
120 loff_t pos, loff_t count);
121 void set_page_dirty_balance(struct page *page);
122 void writeback_set_ratelimit(void);
125 extern int nr_pdflush_threads; /* Global so it can be exported to sysctl
129 #endif /* WRITEBACK_H */