Commit | Line | Data |
---|---|---|
1da177e4 | 1 | /* |
f30c2269 | 2 | * include/linux/writeback.h |
1da177e4 LT |
3 | */ |
4 | #ifndef WRITEBACK_H | |
5 | #define WRITEBACK_H | |
6 | ||
e8edc6e0 | 7 | #include <linux/sched.h> |
f5ff8422 | 8 | #include <linux/fs.h> |
e8edc6e0 | 9 | |
1da177e4 LT |
10 | struct backing_dev_info; |
11 | ||
12 | extern spinlock_t inode_lock; | |
13 | extern struct list_head inode_in_use; | |
14 | extern struct list_head inode_unused; | |
15 | ||
1da177e4 LT |
16 | /* |
17 | * fs/fs-writeback.c | |
18 | */ | |
19 | enum writeback_sync_modes { | |
20 | WB_SYNC_NONE, /* Don't wait on anything */ | |
21 | WB_SYNC_ALL, /* Wait on every mapping */ | |
1da177e4 LT |
22 | }; |
23 | ||
24 | /* | |
25 | * A control structure which tells the writeback code what to do. These are | |
26 | * always on the stack, and hence need no locking. They are always initialised | |
27 | * in a manner such that unspecified fields are set to zero. | |
28 | */ | |
29 | struct writeback_control { | |
30 | struct backing_dev_info *bdi; /* If !NULL, only write back this | |
31 | queue */ | |
03ba3782 JA |
32 | struct super_block *sb; /* if !NULL, only write inodes from |
33 | this super_block */ | |
1da177e4 LT |
34 | enum writeback_sync_modes sync_mode; |
35 | unsigned long *older_than_this; /* If !NULL, only write back inodes | |
36 | older than this */ | |
f11c9c5c ES |
37 | unsigned long wb_start; /* Time writeback_inodes_wb was |
38 | called. This is needed to avoid | |
39 | extra jobs and livelock */ | |
1da177e4 LT |
40 | long nr_to_write; /* Write this many pages, and decrement |
41 | this for each page written */ | |
42 | long pages_skipped; /* Pages which were not written */ | |
43 | ||
44 | /* | |
45 | * For a_ops->writepages(): is start or end are non-zero then this is | |
46 | * a hint that the filesystem need only write out the pages inside that | |
47 | * byterange. The byte at `end' is included in the writeout request. | |
48 | */ | |
111ebb6e OH |
49 | loff_t range_start; |
50 | loff_t range_end; | |
1da177e4 | 51 | |
22905f77 AM |
52 | unsigned nonblocking:1; /* Don't get stuck on request queues */ |
53 | unsigned encountered_congestion:1; /* An output: a queue is full */ | |
54 | unsigned for_kupdate:1; /* A kupdate writeback */ | |
b17621fe | 55 | unsigned for_background:1; /* A background writeback */ |
22905f77 | 56 | unsigned for_reclaim:1; /* Invoked from the page allocator */ |
111ebb6e | 57 | unsigned range_cyclic:1; /* range_start is cyclic */ |
8bc3be27 | 58 | unsigned more_io:1; /* more io to be dispatched */ |
17bc6c30 AK |
59 | /* |
60 | * write_cache_pages() won't update wbc->nr_to_write and | |
61 | * mapping->writeback_index if no_nrwrite_index_update | |
62 | * is set. write_cache_pages() may write more than we | |
63 | * requested and we want to make sure nr_to_write and | |
64 | * writeback_index are updated in a consistent manner | |
65 | * so we use a single control to update them | |
66 | */ | |
67 | unsigned no_nrwrite_index_update:1; | |
e913fc82 JA |
68 | |
69 | /* | |
70 | * For WB_SYNC_ALL, the sb must always be pinned. For WB_SYNC_NONE, | |
71 | * the writeback code will pin the sb for the caller. However, | |
72 | * for eg umount, the caller does WB_SYNC_NONE but already has | |
73 | * the sb pinned. If the below is set, caller already has the | |
74 | * sb pinned. | |
75 | */ | |
76 | unsigned sb_pinned:1; | |
1da177e4 LT |
77 | }; |
78 | ||
1da177e4 LT |
79 | /* |
80 | * fs/fs-writeback.c | |
81 | */ | |
03ba3782 | 82 | struct bdi_writeback; |
1da177e4 | 83 | int inode_wait(void *); |
b6e51316 | 84 | void writeback_inodes_sb(struct super_block *); |
e913fc82 | 85 | void writeback_inodes_sb_locked(struct super_block *); |
17bd55d0 | 86 | int writeback_inodes_sb_if_idle(struct super_block *); |
b6e51316 | 87 | void sync_inodes_sb(struct super_block *); |
03ba3782 JA |
88 | void writeback_inodes_wbc(struct writeback_control *wbc); |
89 | long wb_do_writeback(struct bdi_writeback *wb, int force_wait); | |
90 | void wakeup_flusher_threads(long nr_pages); | |
1da177e4 LT |
91 | |
92 | /* writeback.h requires fs.h; it, too, is not included from here. */ | |
93 | static inline void wait_on_inode(struct inode *inode) | |
94 | { | |
95 | might_sleep(); | |
eaff8079 | 96 | wait_on_bit(&inode->i_state, __I_NEW, inode_wait, TASK_UNINTERRUPTIBLE); |
1da177e4 | 97 | } |
1c0eeaf5 JE |
98 | static inline void inode_sync_wait(struct inode *inode) |
99 | { | |
100 | might_sleep(); | |
101 | wait_on_bit(&inode->i_state, __I_SYNC, inode_wait, | |
102 | TASK_UNINTERRUPTIBLE); | |
103 | } | |
104 | ||
1da177e4 LT |
105 | |
106 | /* | |
107 | * mm/page-writeback.c | |
108 | */ | |
c2c4986e | 109 | #ifdef CONFIG_BLOCK |
31373d09 | 110 | void laptop_io_completion(struct backing_dev_info *info); |
1da177e4 | 111 | void laptop_sync_completion(void); |
31373d09 MG |
112 | void laptop_mode_sync(struct work_struct *work); |
113 | void laptop_mode_timer_fn(unsigned long data); | |
c2c4986e JA |
114 | #else |
115 | static inline void laptop_sync_completion(void) { } | |
116 | #endif | |
232ea4d6 | 117 | void throttle_vm_writeout(gfp_t gfp_mask); |
1da177e4 LT |
118 | |
119 | /* These are exported to sysctl. */ | |
120 | extern int dirty_background_ratio; | |
2da02997 | 121 | extern unsigned long dirty_background_bytes; |
1da177e4 | 122 | extern int vm_dirty_ratio; |
2da02997 | 123 | extern unsigned long vm_dirty_bytes; |
704503d8 AD |
124 | extern unsigned int dirty_writeback_interval; |
125 | extern unsigned int dirty_expire_interval; | |
195cf453 | 126 | extern int vm_highmem_is_dirtyable; |
1da177e4 LT |
127 | extern int block_dump; |
128 | extern int laptop_mode; | |
129 | ||
3eefae99 SR |
130 | extern unsigned long determine_dirtyable_memory(void); |
131 | ||
2da02997 | 132 | extern int dirty_background_ratio_handler(struct ctl_table *table, int write, |
8d65af78 | 133 | void __user *buffer, size_t *lenp, |
2da02997 DR |
134 | loff_t *ppos); |
135 | extern int dirty_background_bytes_handler(struct ctl_table *table, int write, | |
8d65af78 | 136 | void __user *buffer, size_t *lenp, |
2da02997 | 137 | loff_t *ppos); |
04fbfdc1 | 138 | extern int dirty_ratio_handler(struct ctl_table *table, int write, |
8d65af78 | 139 | void __user *buffer, size_t *lenp, |
04fbfdc1 | 140 | loff_t *ppos); |
2da02997 | 141 | extern int dirty_bytes_handler(struct ctl_table *table, int write, |
8d65af78 | 142 | void __user *buffer, size_t *lenp, |
2da02997 | 143 | loff_t *ppos); |
04fbfdc1 | 144 | |
1da177e4 | 145 | struct ctl_table; |
8d65af78 | 146 | int dirty_writeback_centisecs_handler(struct ctl_table *, int, |
1da177e4 LT |
147 | void __user *, size_t *, loff_t *); |
148 | ||
364aeb28 DR |
149 | void get_dirty_limits(unsigned long *pbackground, unsigned long *pdirty, |
150 | unsigned long *pbdi_dirty, struct backing_dev_info *bdi); | |
cf0ca9fe | 151 | |
1da177e4 | 152 | void page_writeback_init(void); |
fa5a734e AM |
153 | void balance_dirty_pages_ratelimited_nr(struct address_space *mapping, |
154 | unsigned long nr_pages_dirtied); | |
155 | ||
156 | static inline void | |
157 | balance_dirty_pages_ratelimited(struct address_space *mapping) | |
158 | { | |
159 | balance_dirty_pages_ratelimited_nr(mapping, 1); | |
160 | } | |
161 | ||
0ea97180 MS |
162 | typedef int (*writepage_t)(struct page *page, struct writeback_control *wbc, |
163 | void *data); | |
164 | ||
0ea97180 MS |
165 | int generic_writepages(struct address_space *mapping, |
166 | struct writeback_control *wbc); | |
167 | int write_cache_pages(struct address_space *mapping, | |
168 | struct writeback_control *wbc, writepage_t writepage, | |
169 | void *data); | |
1da177e4 | 170 | int do_writepages(struct address_space *mapping, struct writeback_control *wbc); |
a200ee18 | 171 | void set_page_dirty_balance(struct page *page, int page_mkwrite); |
2d1d43f6 | 172 | void writeback_set_ratelimit(void); |
1da177e4 LT |
173 | |
174 | /* pdflush.c */ | |
175 | extern int nr_pdflush_threads; /* Global so it can be exported to sysctl | |
176 | read-only. */ | |
177 | ||
178 | ||
179 | #endif /* WRITEBACK_H */ |