1
2
3
4
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
15struct bio;
16
17DECLARE_PER_CPU(int, dirty_throttle_leaks);
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32#define DIRTY_SCOPE 8
33#define DIRTY_FULL_SCOPE (DIRTY_SCOPE / 2)
34
35struct backing_dev_info;
36
37
38
39
40enum writeback_sync_modes {
41 WB_SYNC_NONE,
42 WB_SYNC_ALL,
43};
44
45
46
47
48enum wb_reason {
49 WB_REASON_BACKGROUND,
50 WB_REASON_VMSCAN,
51 WB_REASON_SYNC,
52 WB_REASON_PERIODIC,
53 WB_REASON_LAPTOP_TIMER,
54 WB_REASON_FREE_MORE_MEM,
55 WB_REASON_FS_FREE_SPACE,
56
57
58
59
60
61
62 WB_REASON_FORKER_THREAD,
63
64 WB_REASON_MAX,
65};
66
67
68
69
70
71
72struct writeback_control {
73 long nr_to_write;
74
75 long pages_skipped;
76
77
78
79
80
81
82 loff_t range_start;
83 loff_t range_end;
84
85 enum writeback_sync_modes sync_mode;
86
87 unsigned for_kupdate:1;
88 unsigned for_background:1;
89 unsigned tagged_writepages:1;
90 unsigned for_reclaim:1;
91 unsigned range_cyclic:1;
92 unsigned for_sync:1;
93#ifdef CONFIG_CGROUP_WRITEBACK
94 struct bdi_writeback *wb;
95 struct inode *inode;
96
97
98 int wb_id;
99 int wb_lcand_id;
100 int wb_tcand_id;
101 size_t wb_bytes;
102 size_t wb_lcand_bytes;
103 size_t wb_tcand_bytes;
104#endif
105};
106
107static inline int wbc_to_write_flags(struct writeback_control *wbc)
108{
109 if (wbc->sync_mode == WB_SYNC_ALL)
110 return REQ_SYNC;
111 else if (wbc->for_kupdate || wbc->for_background)
112 return REQ_BACKGROUND;
113
114 return 0;
115}
116
117
118
119
120
121
122
123
124struct wb_domain {
125 spinlock_t lock;
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144 struct fprop_global completions;
145 struct timer_list period_timer;
146 unsigned long period_time;
147
148
149
150
151
152
153
154
155
156
157
158 unsigned long dirty_limit_tstamp;
159 unsigned long dirty_limit;
160};
161
162
163
164
165
166
167
168
169
170
171
172
173
174static inline void wb_domain_size_changed(struct wb_domain *dom)
175{
176 spin_lock(&dom->lock);
177 dom->dirty_limit_tstamp = jiffies;
178 dom->dirty_limit = 0;
179 spin_unlock(&dom->lock);
180}
181
182
183
184
185struct bdi_writeback;
186void writeback_inodes_sb(struct super_block *, enum wb_reason reason);
187void writeback_inodes_sb_nr(struct super_block *, unsigned long nr,
188 enum wb_reason reason);
189bool try_to_writeback_inodes_sb(struct super_block *, enum wb_reason reason);
190bool try_to_writeback_inodes_sb_nr(struct super_block *, unsigned long nr,
191 enum wb_reason reason);
192void sync_inodes_sb(struct super_block *);
193void wakeup_flusher_threads(long nr_pages, enum wb_reason reason);
194void inode_wait_for_writeback(struct inode *inode);
195
196
197static inline void wait_on_inode(struct inode *inode)
198{
199 might_sleep();
200 wait_on_bit(&inode->i_state, __I_NEW, TASK_UNINTERRUPTIBLE);
201}
202
203#ifdef CONFIG_CGROUP_WRITEBACK
204
205#include <linux/cgroup.h>
206#include <linux/bio.h>
207
208void __inode_attach_wb(struct inode *inode, struct page *page);
209void wbc_attach_and_unlock_inode(struct writeback_control *wbc,
210 struct inode *inode)
211 __releases(&inode->i_lock);
212void wbc_detach_inode(struct writeback_control *wbc);
213void wbc_account_io(struct writeback_control *wbc, struct page *page,
214 size_t bytes);
215void cgroup_writeback_umount(void);
216
217
218
219
220
221
222
223
224
225
226static inline void inode_attach_wb(struct inode *inode, struct page *page)
227{
228 if (!inode->i_wb)
229 __inode_attach_wb(inode, page);
230}
231
232
233
234
235
236
237
238static inline void inode_detach_wb(struct inode *inode)
239{
240 if (inode->i_wb) {
241 WARN_ON_ONCE(!(inode->i_state & I_CLEAR));
242 wb_put(inode->i_wb);
243 inode->i_wb = NULL;
244 }
245}
246
247
248
249
250
251
252
253
254
255
256static inline void wbc_attach_fdatawrite_inode(struct writeback_control *wbc,
257 struct inode *inode)
258{
259 spin_lock(&inode->i_lock);
260 inode_attach_wb(inode, NULL);
261 wbc_attach_and_unlock_inode(wbc, inode);
262}
263
264
265
266
267
268
269
270
271
272
273static inline void wbc_init_bio(struct writeback_control *wbc, struct bio *bio)
274{
275
276
277
278
279
280
281 if (wbc->wb)
282 bio_associate_blkcg(bio, wbc->wb->blkcg_css);
283}
284
285#else
286
287static inline void inode_attach_wb(struct inode *inode, struct page *page)
288{
289}
290
291static inline void inode_detach_wb(struct inode *inode)
292{
293}
294
295static inline void wbc_attach_and_unlock_inode(struct writeback_control *wbc,
296 struct inode *inode)
297 __releases(&inode->i_lock)
298{
299 spin_unlock(&inode->i_lock);
300}
301
302static inline void wbc_attach_fdatawrite_inode(struct writeback_control *wbc,
303 struct inode *inode)
304{
305}
306
307static inline void wbc_detach_inode(struct writeback_control *wbc)
308{
309}
310
311static inline void wbc_init_bio(struct writeback_control *wbc, struct bio *bio)
312{
313}
314
315static inline void wbc_account_io(struct writeback_control *wbc,
316 struct page *page, size_t bytes)
317{
318}
319
320static inline void cgroup_writeback_umount(void)
321{
322}
323
324#endif
325
326
327
328
329#ifdef CONFIG_BLOCK
330void laptop_io_completion(struct backing_dev_info *info);
331void laptop_sync_completion(void);
332void laptop_mode_sync(struct work_struct *work);
333void laptop_mode_timer_fn(unsigned long data);
334#else
335static inline void laptop_sync_completion(void) { }
336#endif
337bool node_dirty_ok(struct pglist_data *pgdat);
338int wb_domain_init(struct wb_domain *dom, gfp_t gfp);
339#ifdef CONFIG_CGROUP_WRITEBACK
340void wb_domain_exit(struct wb_domain *dom);
341#endif
342
343extern struct wb_domain global_wb_domain;
344
345
346extern int dirty_background_ratio;
347extern unsigned long dirty_background_bytes;
348extern int vm_dirty_ratio;
349extern unsigned long vm_dirty_bytes;
350extern unsigned int dirty_writeback_interval;
351extern unsigned int dirty_expire_interval;
352extern unsigned int dirtytime_expire_interval;
353extern int vm_highmem_is_dirtyable;
354extern int block_dump;
355extern int laptop_mode;
356
357extern int dirty_background_ratio_handler(struct ctl_table *table, int write,
358 void __user *buffer, size_t *lenp,
359 loff_t *ppos);
360extern int dirty_background_bytes_handler(struct ctl_table *table, int write,
361 void __user *buffer, size_t *lenp,
362 loff_t *ppos);
363extern int dirty_ratio_handler(struct ctl_table *table, int write,
364 void __user *buffer, size_t *lenp,
365 loff_t *ppos);
366extern int dirty_bytes_handler(struct ctl_table *table, int write,
367 void __user *buffer, size_t *lenp,
368 loff_t *ppos);
369int dirtytime_interval_handler(struct ctl_table *table, int write,
370 void __user *buffer, size_t *lenp, loff_t *ppos);
371
372struct ctl_table;
373int dirty_writeback_centisecs_handler(struct ctl_table *, int,
374 void __user *, size_t *, loff_t *);
375
376void global_dirty_limits(unsigned long *pbackground, unsigned long *pdirty);
377unsigned long wb_calc_thresh(struct bdi_writeback *wb, unsigned long thresh);
378
379void wb_update_bandwidth(struct bdi_writeback *wb, unsigned long start_time);
380void balance_dirty_pages_ratelimited(struct address_space *mapping);
381bool wb_over_bg_thresh(struct bdi_writeback *wb);
382
383typedef int (*writepage_t)(struct page *page, struct writeback_control *wbc,
384 void *data);
385
386int generic_writepages(struct address_space *mapping,
387 struct writeback_control *wbc);
388void tag_pages_for_writeback(struct address_space *mapping,
389 pgoff_t start, pgoff_t end);
390int write_cache_pages(struct address_space *mapping,
391 struct writeback_control *wbc, writepage_t writepage,
392 void *data);
393int do_writepages(struct address_space *mapping, struct writeback_control *wbc);
394void writeback_set_ratelimit(void);
395void tag_pages_for_writeback(struct address_space *mapping,
396 pgoff_t start, pgoff_t end);
397
398void account_page_redirty(struct page *page);
399
400void sb_mark_inode_writeback(struct inode *inode);
401void sb_clear_inode_writeback(struct inode *inode);
402
403#endif
404