[deliverable/linux.git] / include / linux / backing-dev-defs.h

#ifndef __LINUX_BACKING_DEV_DEFS_H
#define __LINUX_BACKING_DEV_DEFS_H

#include <linux/list.h>
#include <linux/spinlock.h>
#include <linux/percpu_counter.h>
#include <linux/flex_proportions.h>
#include <linux/timer.h>
#include <linux/workqueue.h>

struct page;
struct device;
struct dentry;

/*
 * Bits in bdi_writeback.state
 */
enum wb_state {
	WB_async_congested,	/* The async (write) queue is getting full */
	WB_sync_congested,	/* The sync queue is getting full */
	WB_registered,		/* bdi_register() was done */
	WB_writeback_running,	/* Writeback is in progress */
};

typedef int (congested_fn)(void *, int);

enum wb_stat_item {
	WB_RECLAIMABLE,
	WB_WRITEBACK,
	WB_DIRTIED,
	WB_WRITTEN,
	NR_WB_STAT_ITEMS
};

#define WB_STAT_BATCH (8*(1+ilog2(nr_cpu_ids)))

struct bdi_writeback {
	struct backing_dev_info *bdi;	/* our parent bdi */

	unsigned long state;		/* Always use atomic bitops on this */
	unsigned long last_old_flush;	/* last old data flush */

	struct list_head b_dirty;	/* dirty inodes */
	struct list_head b_io;		/* parked for writeback */
	struct list_head b_more_io;	/* parked for more writeback */
	struct list_head b_dirty_time;	/* time stamps are dirty */
	spinlock_t list_lock;		/* protects the b_* lists */

	struct percpu_counter stat[NR_WB_STAT_ITEMS];

	unsigned long bw_time_stamp;	/* last time write bw is updated */
	unsigned long dirtied_stamp;
	unsigned long written_stamp;	/* pages written at bw_time_stamp */
	unsigned long write_bandwidth;	/* the estimated write bandwidth */
	unsigned long avg_write_bandwidth; /* further smoothed write bw */

	/*
	 * The base dirty throttle rate, re-calculated on every 200ms.
	 * All the bdi tasks' dirty rate will be curbed under it.
	 * @dirty_ratelimit tracks the estimated @balanced_dirty_ratelimit
	 * in small steps and is much more smooth/stable than the latter.
	 */
	unsigned long dirty_ratelimit;
	unsigned long balanced_dirty_ratelimit;

	struct fprop_local_percpu completions;
	int dirty_exceeded;

	spinlock_t work_lock;		/* protects work_list & dwork scheduling */
	struct list_head work_list;
	struct delayed_work dwork;	/* work item used for writeback */
};

struct backing_dev_info {
	struct list_head bdi_list;
	unsigned long ra_pages;	/* max readahead in PAGE_CACHE_SIZE units */
	unsigned int capabilities; /* Device capabilities */
	congested_fn *congested_fn; /* Function pointer if device is md/dm */
	void *congested_data;	/* Pointer to aux data for congested func */

	char *name;

	unsigned int min_ratio;
	unsigned int max_ratio, max_prop_frac;

	struct bdi_writeback wb;  /* default writeback info for this bdi */

	struct device *dev;

	struct timer_list laptop_mode_wb_timer;

#ifdef CONFIG_DEBUG_FS
	struct dentry *debug_dir;
	struct dentry *debug_stats;
#endif
};

enum {
	BLK_RW_ASYNC	= 0,
	BLK_RW_SYNC	= 1,
};

void clear_bdi_congested(struct backing_dev_info *bdi, int sync);
void set_bdi_congested(struct backing_dev_info *bdi, int sync);

#endif	/* __LINUX_BACKING_DEV_DEFS_H */
Commit	Line	Data
66114cad TH	1	#ifndef __LINUX_BACKING_DEV_DEFS_H
	2	#define __LINUX_BACKING_DEV_DEFS_H
	3
	4	#include <linux/list.h>
	5	#include <linux/spinlock.h>
	6	#include <linux/percpu_counter.h>
	7	#include <linux/flex_proportions.h>
	8	#include <linux/timer.h>
	9	#include <linux/workqueue.h>
	10
	11	struct page;
	12	struct device;
	13	struct dentry;
	14
	15	/*
	16	* Bits in bdi_writeback.state
	17	*/
	18	enum wb_state {
	19	WB_async_congested, /* The async (write) queue is getting full */
	20	WB_sync_congested, /* The sync queue is getting full */
	21	WB_registered, /* bdi_register() was done */
	22	WB_writeback_running, /* Writeback is in progress */
	23	};
	24
	25	typedef int (congested_fn)(void *, int);
	26
	27	enum wb_stat_item {
	28	WB_RECLAIMABLE,
	29	WB_WRITEBACK,
	30	WB_DIRTIED,
	31	WB_WRITTEN,
	32	NR_WB_STAT_ITEMS
	33	};
	34
	35	#define WB_STAT_BATCH (8*(1+ilog2(nr_cpu_ids)))
	36
	37	struct bdi_writeback {
	38	struct backing_dev_info bdi; / our parent bdi */
	39
	40	unsigned long state; /* Always use atomic bitops on this */
	41	unsigned long last_old_flush; /* last old data flush */
	42
	43	struct list_head b_dirty; /* dirty inodes */
	44	struct list_head b_io; /* parked for writeback */
	45	struct list_head b_more_io; /* parked for more writeback */
	46	struct list_head b_dirty_time; /* time stamps are dirty */
	47	spinlock_t list_lock; /* protects the b_* lists */
	48
	49	struct percpu_counter stat[NR_WB_STAT_ITEMS];
	50
	51	unsigned long bw_time_stamp; /* last time write bw is updated */
	52	unsigned long dirtied_stamp;
	53	unsigned long written_stamp; /* pages written at bw_time_stamp */
	54	unsigned long write_bandwidth; /* the estimated write bandwidth */
	55	unsigned long avg_write_bandwidth; /* further smoothed write bw */
	56
	57	/*
	58	* The base dirty throttle rate, re-calculated on every 200ms.
	59	* All the bdi tasks' dirty rate will be curbed under it.
	60	* @dirty_ratelimit tracks the estimated @balanced_dirty_ratelimit
	61	* in small steps and is much more smooth/stable than the latter.
	62	*/
	63	unsigned long dirty_ratelimit;
	64	unsigned long balanced_dirty_ratelimit;
65
66	struct fprop_local_percpu completions;
67	int dirty_exceeded;
68
69	spinlock_t work_lock; /* protects work_list & dwork scheduling */
70	struct list_head work_list;
71	struct delayed_work dwork; /* work item used for writeback */
72	};
73
74	struct backing_dev_info {
75	struct list_head bdi_list;
76	unsigned long ra_pages; /* max readahead in PAGE_CACHE_SIZE units */
77	unsigned int capabilities; /* Device capabilities */
78	congested_fn congested_fn; / Function pointer if device is md/dm */
79	void congested_data; / Pointer to aux data for congested func */
80
81	char *name;
82
83	unsigned int min_ratio;
84	unsigned int max_ratio, max_prop_frac;
85
86	struct bdi_writeback wb; /* default writeback info for this bdi */
87
88	struct device *dev;
89
90	struct timer_list laptop_mode_wb_timer;
91
92	#ifdef CONFIG_DEBUG_FS
93	struct dentry *debug_dir;
94	struct dentry *debug_stats;
95	#endif
96	};
97
98	enum {
99	BLK_RW_ASYNC = 0,
100	BLK_RW_SYNC = 1,
101	};
102
103	void clear_bdi_congested(struct backing_dev_info *bdi, int sync);
104	void set_bdi_congested(struct backing_dev_info *bdi, int sync);
105
106	#endif /* __LINUX_BACKING_DEV_DEFS_H */