/*
- * include/linux/writeback.h.
+ * include/linux/writeback.h
*/
#ifndef WRITEBACK_H
#define WRITEBACK_H
-struct backing_dev_info;
+#include <linux/sched.h>
+#include <linux/fs.h>
-extern spinlock_t inode_lock;
-extern struct list_head inode_in_use;
-extern struct list_head inode_unused;
+/*
+ * The 1/4 region under the global dirty thresh is for smooth dirty throttling:
+ *
+ * (thresh - thresh/DIRTY_FULL_SCOPE, thresh)
+ *
+ * Further beyond, all dirtier tasks will enter a loop waiting (possibly long
+ * time) for the dirty pages to drop, unless written enough pages.
+ *
+ * The global dirty threshold is normally equal to the global dirty limit,
+ * except when the system suddenly allocates a lot of anonymous memory and
+ * knocks down the global dirty threshold quickly, in which case the global
+ * dirty limit will follow down slowly to prevent livelocking all dirtier tasks.
+ */
+#define DIRTY_SCOPE 8
+#define DIRTY_FULL_SCOPE (DIRTY_SCOPE / 2)
/*
- * Yes, writeback.h requires sched.h
- * No, sched.h is not included from here.
+ * 4MB minimal write chunk size
*/
-static inline int task_is_pdflush(struct task_struct *task)
-{
- return task->flags & PF_FLUSHER;
-}
+#define MIN_WRITEBACK_PAGES (4096UL >> (PAGE_CACHE_SHIFT - 10))
-#define current_is_pdflush() task_is_pdflush(current)
+struct backing_dev_info;
/*
* 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() */
};
/*
* 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 */
* 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 */
+ loff_t range_start;
+ loff_t range_end;
+
+ unsigned for_kupdate:1; /* A kupdate writeback */
+ unsigned for_background:1; /* A background writeback */
+ unsigned tagged_writepages:1; /* tag-and-write to avoid livelock */
+ unsigned for_reclaim:1; /* Invoked from the page allocator */
+ unsigned range_cyclic:1; /* range_start is cyclic */
};
-/*
- * ->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);
+struct bdi_writeback;
int inode_wait(void *);
-void sync_inodes_sb(struct super_block *, int wait);
-void sync_inodes(int wait);
+void writeback_inodes_sb(struct super_block *);
+void writeback_inodes_sb_nr(struct super_block *, unsigned long nr);
+int writeback_inodes_sb_if_idle(struct super_block *);
+int writeback_inodes_sb_nr_if_idle(struct super_block *, unsigned long nr);
+void sync_inodes_sb(struct super_block *);
+long writeback_inodes_wb(struct bdi_writeback *wb, long nr_pages);
+long wb_do_writeback(struct bdi_writeback *wb, int force_wait);
+void wakeup_flusher_threads(long nr_pages);
/* 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,
+ wait_on_bit(&inode->i_state, __I_NEW, inode_wait, TASK_UNINTERRUPTIBLE);
+}
+static inline void inode_sync_wait(struct inode *inode)
+{
+ might_sleep();
+ wait_on_bit(&inode->i_state, __I_SYNC, inode_wait,
TASK_UNINTERRUPTIBLE);
}
+
/*
* mm/page-writeback.c
*/
-int wakeup_pdflush(long nr_pages);
-void laptop_io_completion(void);
+#ifdef CONFIG_BLOCK
+void laptop_io_completion(struct backing_dev_info *info);
void laptop_sync_completion(void);
-void throttle_vm_writeout(void);
+void laptop_mode_sync(struct work_struct *work);
+void laptop_mode_timer_fn(unsigned long data);
+#else
+static inline void laptop_sync_completion(void) { }
+#endif
+void throttle_vm_writeout(gfp_t gfp_mask);
+
+extern unsigned long global_dirty_limit;
/* These are exported to sysctl. */
extern int dirty_background_ratio;
+extern unsigned long dirty_background_bytes;
extern int vm_dirty_ratio;
-extern int dirty_writeback_centisecs;
-extern int dirty_expire_centisecs;
+extern unsigned long vm_dirty_bytes;
+extern unsigned int dirty_writeback_interval;
+extern unsigned int dirty_expire_interval;
+extern int vm_highmem_is_dirtyable;
extern int block_dump;
extern int laptop_mode;
+extern unsigned long determine_dirtyable_memory(void);
+
+extern int dirty_background_ratio_handler(struct ctl_table *table, int write,
+ void __user *buffer, size_t *lenp,
+ loff_t *ppos);
+extern int dirty_background_bytes_handler(struct ctl_table *table, int write,
+ void __user *buffer, size_t *lenp,
+ loff_t *ppos);
+extern int dirty_ratio_handler(struct ctl_table *table, int write,
+ void __user *buffer, size_t *lenp,
+ loff_t *ppos);
+extern int dirty_bytes_handler(struct ctl_table *table, int write,
+ void __user *buffer, size_t *lenp,
+ loff_t *ppos);
+
struct ctl_table;
-struct file;
-int dirty_writeback_centisecs_handler(struct ctl_table *, int, struct file *,
+int dirty_writeback_centisecs_handler(struct ctl_table *, int,
void __user *, size_t *, loff_t *);
+void global_dirty_limits(unsigned long *pbackground, unsigned long *pdirty);
+unsigned long bdi_dirty_limit(struct backing_dev_info *bdi,
+ unsigned long dirty);
+
+void __bdi_update_bandwidth(struct backing_dev_info *bdi,
+ unsigned long thresh,
+ unsigned long dirty,
+ unsigned long bdi_thresh,
+ unsigned long bdi_dirty,
+ unsigned long start_time);
+
void page_writeback_init(void);
-void balance_dirty_pages_ratelimited(struct address_space *mapping);
-int pdflush_operation(void (*fn)(unsigned long), unsigned long arg0);
+void balance_dirty_pages_ratelimited_nr(struct address_space *mapping,
+ unsigned long nr_pages_dirtied);
+
+static inline void
+balance_dirty_pages_ratelimited(struct address_space *mapping)
+{
+ balance_dirty_pages_ratelimited_nr(mapping, 1);
+}
+
+typedef int (*writepage_t)(struct page *page, struct writeback_control *wbc,
+ void *data);
+
+int generic_writepages(struct address_space *mapping,
+ struct writeback_control *wbc);
+void tag_pages_for_writeback(struct address_space *mapping,
+ pgoff_t start, pgoff_t end);
+int write_cache_pages(struct address_space *mapping,
+ struct writeback_control *wbc, writepage_t writepage,
+ void *data);
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);
+void set_page_dirty_balance(struct page *page, int page_mkwrite);
+void writeback_set_ratelimit(void);
+void tag_pages_for_writeback(struct address_space *mapping,
+ pgoff_t start, pgoff_t end);
/* pdflush.c */
extern int nr_pdflush_threads; /* Global so it can be exported to sysctl