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author | Linus Torvalds <torvalds@ppc970.osdl.org> | 2005-04-16 22:20:36 (GMT) |
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committer | Linus Torvalds <torvalds@ppc970.osdl.org> | 2005-04-16 22:20:36 (GMT) |
commit | 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 (patch) | |
tree | 0bba044c4ce775e45a88a51686b5d9f90697ea9d /include/linux/writeback.h | |
download | linux-fsl-qoriq-1da177e4c3f41524e886b7f1b8a0c1fc7321cac2.tar.xz |
Linux-2.6.12-rc2
Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.
Let it rip!
Diffstat (limited to 'include/linux/writeback.h')
-rw-r--r-- | include/linux/writeback.h | 118 |
1 files changed, 118 insertions, 0 deletions
diff --git a/include/linux/writeback.h b/include/linux/writeback.h new file mode 100644 index 0000000..1262cb4 --- /dev/null +++ b/include/linux/writeback.h @@ -0,0 +1,118 @@ +/* + * include/linux/writeback.h. + */ +#ifndef WRITEBACK_H +#define WRITEBACK_H + +struct backing_dev_info; + +extern spinlock_t inode_lock; +extern struct list_head inode_in_use; +extern struct list_head inode_unused; + +/* + * Yes, writeback.h requires sched.h + * No, sched.h is not included from here. + */ +static inline int current_is_pdflush(void) +{ + return current->flags & PF_FLUSHER; +} + +/* + * fs/fs-writeback.c + */ +enum writeback_sync_modes { + WB_SYNC_NONE, /* Don't wait on anything */ + WB_SYNC_ALL, /* Wait on every mapping */ + WB_SYNC_HOLD, /* Hold the inode on sb_dirty for sys_sync() */ +}; + +/* + * A control structure which tells the writeback code what to do. These are + * always on the stack, and hence need no locking. They are always initialised + * in a manner such that unspecified fields are set to zero. + */ +struct writeback_control { + struct backing_dev_info *bdi; /* If !NULL, only write back this + queue */ + enum writeback_sync_modes sync_mode; + unsigned long *older_than_this; /* If !NULL, only write back inodes + older than this */ + long nr_to_write; /* Write this many pages, and decrement + this for each page written */ + long pages_skipped; /* Pages which were not written */ + + /* + * For a_ops->writepages(): is start or end are non-zero then this is + * a hint that the filesystem need only write out the pages inside that + * byterange. The byte at `end' is included in the writeout request. + */ + loff_t start; + loff_t end; + + unsigned nonblocking:1; /* Don't get stuck on request queues */ + unsigned encountered_congestion:1; /* An output: a queue is full */ + unsigned for_kupdate:1; /* A kupdate writeback */ + unsigned for_reclaim:1; /* Invoked from the page allocator */ +}; + +/* + * ->writepage() return values (make these much larger than a pagesize, in + * case some fs is returning number-of-bytes-written from writepage) + */ +#define WRITEPAGE_ACTIVATE 0x80000 /* IO was not started: activate page */ + +/* + * fs/fs-writeback.c + */ +void writeback_inodes(struct writeback_control *wbc); +void wake_up_inode(struct inode *inode); +int inode_wait(void *); +void sync_inodes_sb(struct super_block *, int wait); +void sync_inodes(int wait); + +/* writeback.h requires fs.h; it, too, is not included from here. */ +static inline void wait_on_inode(struct inode *inode) +{ + might_sleep(); + wait_on_bit(&inode->i_state, __I_LOCK, inode_wait, + TASK_UNINTERRUPTIBLE); +} + +/* + * mm/page-writeback.c + */ +int wakeup_bdflush(long nr_pages); +void laptop_io_completion(void); +void laptop_sync_completion(void); +void throttle_vm_writeout(void); + +/* These are exported to sysctl. */ +extern int dirty_background_ratio; +extern int vm_dirty_ratio; +extern int dirty_writeback_centisecs; +extern int dirty_expire_centisecs; +extern int block_dump; +extern int laptop_mode; + +struct ctl_table; +struct file; +int dirty_writeback_centisecs_handler(struct ctl_table *, int, struct file *, + void __user *, size_t *, loff_t *); + +void page_writeback_init(void); +void balance_dirty_pages_ratelimited(struct address_space *mapping); +int pdflush_operation(void (*fn)(unsigned long), unsigned long arg0); +int do_writepages(struct address_space *mapping, struct writeback_control *wbc); +int sync_page_range(struct inode *inode, struct address_space *mapping, + loff_t pos, size_t count); +int sync_page_range_nolock(struct inode *inode, struct address_space + *mapping, loff_t pos, size_t count); + +/* pdflush.c */ +extern int nr_pdflush_threads; /* Global so it can be exported to sysctl + read-only. */ + + +#endif /* WRITEBACK_H */ |