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5#ifndef WRITEBACK_H
6#define WRITEBACK_H
7
8#include <linux/sched.h>
9#include <linux/workqueue.h>
10#include <linux/fs.h>
11#include <linux/flex_proportions.h>
12#include <linux/backing-dev-defs.h>
13#include <linux/blk_types.h>
14#include <linux/blk-cgroup.h>
15
16struct bio;
17
18DECLARE_PER_CPU(int, dirty_throttle_leaks);
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31
32
33#define DIRTY_SCOPE 8
34#define DIRTY_FULL_SCOPE (DIRTY_SCOPE / 2)
35
36struct backing_dev_info;
37
38
39
40
41enum writeback_sync_modes {
42 WB_SYNC_NONE,
43 WB_SYNC_ALL,
44};
45
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49
50
51struct writeback_control {
52 long nr_to_write;
53
54 long pages_skipped;
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60
61 loff_t range_start;
62 loff_t range_end;
63
64 enum writeback_sync_modes sync_mode;
65
66 unsigned for_kupdate:1;
67 unsigned for_background:1;
68 unsigned tagged_writepages:1;
69 unsigned for_reclaim:1;
70 unsigned range_cyclic:1;
71 unsigned for_sync:1;
72
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78
79 unsigned no_cgroup_owner:1;
80
81 unsigned punt_to_cgroup:1;
82
83#ifdef CONFIG_CGROUP_WRITEBACK
84 struct bdi_writeback *wb;
85 struct inode *inode;
86
87
88 int wb_id;
89 int wb_lcand_id;
90 int wb_tcand_id;
91 size_t wb_bytes;
92 size_t wb_lcand_bytes;
93 size_t wb_tcand_bytes;
94#endif
95};
96
97static inline int wbc_to_write_flags(struct writeback_control *wbc)
98{
99 int flags = 0;
100
101 if (wbc->punt_to_cgroup)
102 flags = REQ_CGROUP_PUNT;
103
104 if (wbc->sync_mode == WB_SYNC_ALL)
105 flags |= REQ_SYNC;
106 else if (wbc->for_kupdate || wbc->for_background)
107 flags |= REQ_BACKGROUND;
108
109 return flags;
110}
111
112static inline struct cgroup_subsys_state *
113wbc_blkcg_css(struct writeback_control *wbc)
114{
115#ifdef CONFIG_CGROUP_WRITEBACK
116 if (wbc->wb)
117 return wbc->wb->blkcg_css;
118#endif
119 return blkcg_root_css;
120}
121
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127
128
129struct wb_domain {
130 spinlock_t lock;
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148
149 struct fprop_global completions;
150 struct timer_list period_timer;
151 unsigned long period_time;
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162
163 unsigned long dirty_limit_tstamp;
164 unsigned long dirty_limit;
165};
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178
179static inline void wb_domain_size_changed(struct wb_domain *dom)
180{
181 spin_lock(&dom->lock);
182 dom->dirty_limit_tstamp = jiffies;
183 dom->dirty_limit = 0;
184 spin_unlock(&dom->lock);
185}
186
187
188
189
190struct bdi_writeback;
191void writeback_inodes_sb(struct super_block *, enum wb_reason reason);
192void writeback_inodes_sb_nr(struct super_block *, unsigned long nr,
193 enum wb_reason reason);
194void try_to_writeback_inodes_sb(struct super_block *sb, enum wb_reason reason);
195void sync_inodes_sb(struct super_block *);
196void wakeup_flusher_threads(enum wb_reason reason);
197void wakeup_flusher_threads_bdi(struct backing_dev_info *bdi,
198 enum wb_reason reason);
199void inode_wait_for_writeback(struct inode *inode);
200
201
202static inline void wait_on_inode(struct inode *inode)
203{
204 might_sleep();
205 wait_on_bit(&inode->i_state, __I_NEW, TASK_UNINTERRUPTIBLE);
206}
207
208#ifdef CONFIG_CGROUP_WRITEBACK
209
210#include <linux/cgroup.h>
211#include <linux/bio.h>
212
213void __inode_attach_wb(struct inode *inode, struct page *page);
214void wbc_attach_and_unlock_inode(struct writeback_control *wbc,
215 struct inode *inode)
216 __releases(&inode->i_lock);
217void wbc_detach_inode(struct writeback_control *wbc);
218void wbc_account_cgroup_owner(struct writeback_control *wbc, struct page *page,
219 size_t bytes);
220void cgroup_writeback_umount(void);
221
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229
230
231static inline void inode_attach_wb(struct inode *inode, struct page *page)
232{
233 if (!inode->i_wb)
234 __inode_attach_wb(inode, page);
235}
236
237
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241
242
243static inline void inode_detach_wb(struct inode *inode)
244{
245 if (inode->i_wb) {
246 WARN_ON_ONCE(!(inode->i_state & I_CLEAR));
247 wb_put(inode->i_wb);
248 inode->i_wb = NULL;
249 }
250}
251
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259
260
261static inline void wbc_attach_fdatawrite_inode(struct writeback_control *wbc,
262 struct inode *inode)
263{
264 spin_lock(&inode->i_lock);
265 inode_attach_wb(inode, NULL);
266 wbc_attach_and_unlock_inode(wbc, inode);
267}
268
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278
279static inline void wbc_init_bio(struct writeback_control *wbc, struct bio *bio)
280{
281
282
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284
285
286
287 if (wbc->wb)
288 bio_associate_blkg_from_css(bio, wbc->wb->blkcg_css);
289}
290
291#else
292
293static inline void inode_attach_wb(struct inode *inode, struct page *page)
294{
295}
296
297static inline void inode_detach_wb(struct inode *inode)
298{
299}
300
301static inline void wbc_attach_and_unlock_inode(struct writeback_control *wbc,
302 struct inode *inode)
303 __releases(&inode->i_lock)
304{
305 spin_unlock(&inode->i_lock);
306}
307
308static inline void wbc_attach_fdatawrite_inode(struct writeback_control *wbc,
309 struct inode *inode)
310{
311}
312
313static inline void wbc_detach_inode(struct writeback_control *wbc)
314{
315}
316
317static inline void wbc_init_bio(struct writeback_control *wbc, struct bio *bio)
318{
319}
320
321static inline void wbc_account_cgroup_owner(struct writeback_control *wbc,
322 struct page *page, size_t bytes)
323{
324}
325
326static inline void cgroup_writeback_umount(void)
327{
328}
329
330#endif
331
332
333
334
335#ifdef CONFIG_BLOCK
336void laptop_io_completion(struct backing_dev_info *info);
337void laptop_sync_completion(void);
338void laptop_mode_sync(struct work_struct *work);
339void laptop_mode_timer_fn(struct timer_list *t);
340#else
341static inline void laptop_sync_completion(void) { }
342#endif
343bool node_dirty_ok(struct pglist_data *pgdat);
344int wb_domain_init(struct wb_domain *dom, gfp_t gfp);
345#ifdef CONFIG_CGROUP_WRITEBACK
346void wb_domain_exit(struct wb_domain *dom);
347#endif
348
349extern struct wb_domain global_wb_domain;
350
351
352extern int dirty_background_ratio;
353extern unsigned long dirty_background_bytes;
354extern int vm_dirty_ratio;
355extern unsigned long vm_dirty_bytes;
356extern unsigned int dirty_writeback_interval;
357extern unsigned int dirty_expire_interval;
358extern unsigned int dirtytime_expire_interval;
359extern int vm_highmem_is_dirtyable;
360extern int block_dump;
361extern int laptop_mode;
362
363extern int dirty_background_ratio_handler(struct ctl_table *table, int write,
364 void __user *buffer, size_t *lenp,
365 loff_t *ppos);
366extern int dirty_background_bytes_handler(struct ctl_table *table, int write,
367 void __user *buffer, size_t *lenp,
368 loff_t *ppos);
369extern int dirty_ratio_handler(struct ctl_table *table, int write,
370 void __user *buffer, size_t *lenp,
371 loff_t *ppos);
372extern int dirty_bytes_handler(struct ctl_table *table, int write,
373 void __user *buffer, size_t *lenp,
374 loff_t *ppos);
375int dirtytime_interval_handler(struct ctl_table *table, int write,
376 void __user *buffer, size_t *lenp, loff_t *ppos);
377
378struct ctl_table;
379int dirty_writeback_centisecs_handler(struct ctl_table *, int,
380 void __user *, size_t *, loff_t *);
381
382void global_dirty_limits(unsigned long *pbackground, unsigned long *pdirty);
383unsigned long wb_calc_thresh(struct bdi_writeback *wb, unsigned long thresh);
384
385void wb_update_bandwidth(struct bdi_writeback *wb, unsigned long start_time);
386void balance_dirty_pages_ratelimited(struct address_space *mapping);
387bool wb_over_bg_thresh(struct bdi_writeback *wb);
388
389typedef int (*writepage_t)(struct page *page, struct writeback_control *wbc,
390 void *data);
391
392int generic_writepages(struct address_space *mapping,
393 struct writeback_control *wbc);
394void tag_pages_for_writeback(struct address_space *mapping,
395 pgoff_t start, pgoff_t end);
396int write_cache_pages(struct address_space *mapping,
397 struct writeback_control *wbc, writepage_t writepage,
398 void *data);
399int do_writepages(struct address_space *mapping, struct writeback_control *wbc);
400void writeback_set_ratelimit(void);
401void tag_pages_for_writeback(struct address_space *mapping,
402 pgoff_t start, pgoff_t end);
403
404void account_page_redirty(struct page *page);
405
406void sb_mark_inode_writeback(struct inode *inode);
407void sb_clear_inode_writeback(struct inode *inode);
408
409#endif
410