Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1 | /* |
Uwe Zeisberger | f30c226 | 2006-10-03 23:01:26 +0200 | [diff] [blame] | 2 | * include/linux/writeback.h |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 3 | */ |
| 4 | #ifndef WRITEBACK_H |
| 5 | #define WRITEBACK_H |
| 6 | |
Alexey Dobriyan | e8edc6e | 2007-05-21 01:22:52 +0400 | [diff] [blame] | 7 | #include <linux/sched.h> |
Jens Axboe | f5ff842 | 2007-09-21 09:19:54 +0200 | [diff] [blame] | 8 | #include <linux/fs.h> |
Alexey Dobriyan | e8edc6e | 2007-05-21 01:22:52 +0400 | [diff] [blame] | 9 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 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 | |
| 16 | /* |
| 17 | * Yes, writeback.h requires sched.h |
| 18 | * No, sched.h is not included from here. |
| 19 | */ |
Jens Axboe | 22e2c50 | 2005-06-27 10:55:12 +0200 | [diff] [blame] | 20 | static inline int task_is_pdflush(struct task_struct *task) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 21 | { |
Jens Axboe | 22e2c50 | 2005-06-27 10:55:12 +0200 | [diff] [blame] | 22 | return task->flags & PF_FLUSHER; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 23 | } |
| 24 | |
Jens Axboe | 22e2c50 | 2005-06-27 10:55:12 +0200 | [diff] [blame] | 25 | #define current_is_pdflush() task_is_pdflush(current) |
| 26 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 27 | /* |
| 28 | * fs/fs-writeback.c |
| 29 | */ |
| 30 | enum writeback_sync_modes { |
| 31 | WB_SYNC_NONE, /* Don't wait on anything */ |
| 32 | WB_SYNC_ALL, /* Wait on every mapping */ |
| 33 | WB_SYNC_HOLD, /* Hold the inode on sb_dirty for sys_sync() */ |
| 34 | }; |
| 35 | |
| 36 | /* |
| 37 | * A control structure which tells the writeback code what to do. These are |
| 38 | * always on the stack, and hence need no locking. They are always initialised |
| 39 | * in a manner such that unspecified fields are set to zero. |
| 40 | */ |
| 41 | struct writeback_control { |
| 42 | struct backing_dev_info *bdi; /* If !NULL, only write back this |
| 43 | queue */ |
| 44 | enum writeback_sync_modes sync_mode; |
| 45 | unsigned long *older_than_this; /* If !NULL, only write back inodes |
| 46 | older than this */ |
| 47 | long nr_to_write; /* Write this many pages, and decrement |
| 48 | this for each page written */ |
| 49 | long pages_skipped; /* Pages which were not written */ |
| 50 | |
| 51 | /* |
| 52 | * For a_ops->writepages(): is start or end are non-zero then this is |
| 53 | * a hint that the filesystem need only write out the pages inside that |
| 54 | * byterange. The byte at `end' is included in the writeout request. |
| 55 | */ |
OGAWA Hirofumi | 111ebb6 | 2006-06-23 02:03:26 -0700 | [diff] [blame] | 56 | loff_t range_start; |
| 57 | loff_t range_end; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 58 | |
Andrew Morton | 22905f7 | 2005-11-16 15:07:01 -0800 | [diff] [blame] | 59 | unsigned nonblocking:1; /* Don't get stuck on request queues */ |
| 60 | unsigned encountered_congestion:1; /* An output: a queue is full */ |
| 61 | unsigned for_kupdate:1; /* A kupdate writeback */ |
| 62 | unsigned for_reclaim:1; /* Invoked from the page allocator */ |
| 63 | unsigned for_writepages:1; /* This is a writepages() call */ |
OGAWA Hirofumi | 111ebb6 | 2006-06-23 02:03:26 -0700 | [diff] [blame] | 64 | unsigned range_cyclic:1; /* range_start is cyclic */ |
Fengguang Wu | 8bc3be2 | 2008-02-04 22:29:36 -0800 | [diff] [blame] | 65 | unsigned more_io:1; /* more io to be dispatched */ |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 66 | }; |
| 67 | |
| 68 | /* |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 69 | * fs/fs-writeback.c |
| 70 | */ |
| 71 | void writeback_inodes(struct writeback_control *wbc); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 72 | int inode_wait(void *); |
| 73 | void sync_inodes_sb(struct super_block *, int wait); |
| 74 | void sync_inodes(int wait); |
| 75 | |
| 76 | /* writeback.h requires fs.h; it, too, is not included from here. */ |
| 77 | static inline void wait_on_inode(struct inode *inode) |
| 78 | { |
| 79 | might_sleep(); |
| 80 | wait_on_bit(&inode->i_state, __I_LOCK, inode_wait, |
| 81 | TASK_UNINTERRUPTIBLE); |
| 82 | } |
Joern Engel | 1c0eeaf | 2007-10-16 23:30:44 -0700 | [diff] [blame] | 83 | static inline void inode_sync_wait(struct inode *inode) |
| 84 | { |
| 85 | might_sleep(); |
| 86 | wait_on_bit(&inode->i_state, __I_SYNC, inode_wait, |
| 87 | TASK_UNINTERRUPTIBLE); |
| 88 | } |
| 89 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 90 | |
| 91 | /* |
| 92 | * mm/page-writeback.c |
| 93 | */ |
Pekka J Enberg | 687a21c | 2005-06-28 20:44:55 -0700 | [diff] [blame] | 94 | int wakeup_pdflush(long nr_pages); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 95 | void laptop_io_completion(void); |
| 96 | void laptop_sync_completion(void); |
Andrew Morton | 232ea4d | 2007-02-28 20:13:21 -0800 | [diff] [blame] | 97 | void throttle_vm_writeout(gfp_t gfp_mask); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 98 | |
| 99 | /* These are exported to sysctl. */ |
| 100 | extern int dirty_background_ratio; |
| 101 | extern int vm_dirty_ratio; |
Bart Samwel | f6ef943 | 2006-03-24 03:15:48 -0800 | [diff] [blame] | 102 | extern int dirty_writeback_interval; |
| 103 | extern int dirty_expire_interval; |
Bron Gondwana | 195cf453 | 2008-02-04 22:29:20 -0800 | [diff] [blame] | 104 | extern int vm_highmem_is_dirtyable; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 105 | extern int block_dump; |
| 106 | extern int laptop_mode; |
| 107 | |
Peter Zijlstra | 04fbfdc | 2007-10-16 23:25:50 -0700 | [diff] [blame] | 108 | extern int dirty_ratio_handler(struct ctl_table *table, int write, |
| 109 | struct file *filp, void __user *buffer, size_t *lenp, |
| 110 | loff_t *ppos); |
| 111 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 112 | struct ctl_table; |
| 113 | struct file; |
| 114 | int dirty_writeback_centisecs_handler(struct ctl_table *, int, struct file *, |
| 115 | void __user *, size_t *, loff_t *); |
| 116 | |
Peter Zijlstra | cf0ca9f | 2008-04-30 00:54:32 -0700 | [diff] [blame] | 117 | void get_dirty_limits(long *pbackground, long *pdirty, long *pbdi_dirty, |
| 118 | struct backing_dev_info *bdi); |
| 119 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 120 | void page_writeback_init(void); |
Andrew Morton | fa5a734 | 2006-03-24 03:18:10 -0800 | [diff] [blame] | 121 | void balance_dirty_pages_ratelimited_nr(struct address_space *mapping, |
| 122 | unsigned long nr_pages_dirtied); |
| 123 | |
| 124 | static inline void |
| 125 | balance_dirty_pages_ratelimited(struct address_space *mapping) |
| 126 | { |
| 127 | balance_dirty_pages_ratelimited_nr(mapping, 1); |
| 128 | } |
| 129 | |
Miklos Szeredi | 0ea9718 | 2007-05-10 22:22:51 -0700 | [diff] [blame] | 130 | typedef int (*writepage_t)(struct page *page, struct writeback_control *wbc, |
| 131 | void *data); |
| 132 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 133 | int pdflush_operation(void (*fn)(unsigned long), unsigned long arg0); |
Miklos Szeredi | 0ea9718 | 2007-05-10 22:22:51 -0700 | [diff] [blame] | 134 | int generic_writepages(struct address_space *mapping, |
| 135 | struct writeback_control *wbc); |
| 136 | int write_cache_pages(struct address_space *mapping, |
| 137 | struct writeback_control *wbc, writepage_t writepage, |
| 138 | void *data); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 139 | int do_writepages(struct address_space *mapping, struct writeback_control *wbc); |
| 140 | int sync_page_range(struct inode *inode, struct address_space *mapping, |
OGAWA Hirofumi | 268fc16 | 2006-01-08 01:02:12 -0800 | [diff] [blame] | 141 | loff_t pos, loff_t count); |
| 142 | int sync_page_range_nolock(struct inode *inode, struct address_space *mapping, |
| 143 | loff_t pos, loff_t count); |
Peter Zijlstra | a200ee1 | 2007-10-08 18:54:37 +0200 | [diff] [blame] | 144 | void set_page_dirty_balance(struct page *page, int page_mkwrite); |
Chandra Seetharaman | 2d1d43f | 2006-09-29 02:01:25 -0700 | [diff] [blame] | 145 | void writeback_set_ratelimit(void); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 146 | |
| 147 | /* pdflush.c */ |
| 148 | extern int nr_pdflush_threads; /* Global so it can be exported to sysctl |
| 149 | read-only. */ |
| 150 | |
| 151 | |
| 152 | #endif /* WRITEBACK_H */ |