[net-next-2.6.git] / drivers / md / raid1.h

#ifndef _RAID1_H
#define _RAID1_H

typedef struct mirror_info mirror_info_t;

struct mirror_info {
	mdk_rdev_t	*rdev;
	sector_t	head_position;
};

/*
 * memory pools need a pointer to the mddev, so they can force an unplug
 * when memory is tight, and a count of the number of drives that the
 * pool was allocated for, so they know how much to allocate and free.
 * mddev->raid_disks cannot be used, as it can change while a pool is active
 * These two datums are stored in a kmalloced struct.
 */

struct pool_info {
	mddev_t *mddev;
	int	raid_disks;
};


typedef struct r1bio_s r1bio_t;

struct r1_private_data_s {
	mddev_t			*mddev;
	mirror_info_t		*mirrors;
	int			raid_disks;
	int			last_used;
	sector_t		next_seq_sect;
	spinlock_t		device_lock;

	struct list_head	retry_list;
	/* queue pending writes and submit them on unplug */
	struct bio_list		pending_bio_list;

	/* for use when syncing mirrors: */

	spinlock_t		resync_lock;
	int			nr_pending;
	int			nr_waiting;
	int			nr_queued;
	int			barrier;
	sector_t		next_resync;
	int			fullsync;  /* set to 1 if a full sync is needed,
					    * (fresh device added).
					    * Cleared when a sync completes.
					    */

	wait_queue_head_t	wait_barrier;

	struct pool_info	*poolinfo;

	struct page		*tmppage;

	mempool_t *r1bio_pool;
	mempool_t *r1buf_pool;

	/* When taking over an array from a different personality, we store
	 * the new thread here until we fully activate the array.
	 */
	struct mdk_thread_s	*thread;
};

typedef struct r1_private_data_s conf_t;

/*
 * this is our 'private' RAID1 bio.
 *
 * it contains information about what kind of IO operations were started
 * for this RAID1 operation, and about their status:
 */

struct r1bio_s {
	atomic_t		remaining; /* 'have we finished' count,
					    * used from IRQ handlers
					    */
	atomic_t		behind_remaining; /* number of write-behind ios remaining
						 * in this BehindIO request
						 */
	sector_t		sector;
	int			sectors;
	unsigned long		state;
	mddev_t			*mddev;
	/*
	 * original bio going to /dev/mdx
	 */
	struct bio		*master_bio;
	/*
	 * if the IO is in READ direction, then this is where we read
	 */
	int			read_disk;

	struct list_head	retry_list;
	struct bitmap_update	*bitmap_update;
	/*
	 * if the IO is in WRITE direction, then multiple bios are used.
	 * We choose the number when they are allocated.
	 */
	struct bio		*bios[0];
	/* DO NOT PUT ANY NEW FIELDS HERE - bios array is contiguously alloced*/
};

/* when we get a read error on a read-only array, we redirect to another
 * device without failing the first device, or trying to over-write to
 * correct the read error.  To keep track of bad blocks on a per-bio
 * level, we store IO_BLOCKED in the appropriate 'bios' pointer
 */
#define IO_BLOCKED ((struct bio*)1)

/* bits for r1bio.state */
#define	R1BIO_Uptodate	0
#define	R1BIO_IsSync	1
#define	R1BIO_Degraded	2
#define	R1BIO_BehindIO	3
/* For write-behind requests, we call bi_end_io when
 * the last non-write-behind device completes, providing
 * any write was successful.  Otherwise we call when
 * any write-behind write succeeds, otherwise we call
 * with failure when last write completes (and all failed).
 * Record that bi_end_io was called with this flag...
 */
#define	R1BIO_Returned 6

#endif
Commit	Line	Data
1da177e4 LT	1	#ifndef _RAID1_H
	2	#define _RAID1_H
	3
1da177e4 LT	4	typedef struct mirror_info mirror_info_t;
	5
	6	struct mirror_info {
	7	mdk_rdev_t *rdev;
	8	sector_t head_position;
	9	};
	10
	11	/*
	12	* memory pools need a pointer to the mddev, so they can force an unplug
	13	* when memory is tight, and a count of the number of drives that the
	14	* pool was allocated for, so they know how much to allocate and free.
	15	* mddev->raid_disks cannot be used, as it can change while a pool is active
	16	* These two datums are stored in a kmalloced struct.
	17	*/
	18
	19	struct pool_info {
	20	mddev_t *mddev;
	21	int raid_disks;
	22	};
	23
	24
	25	typedef struct r1bio_s r1bio_t;
	26
	27	struct r1_private_data_s {
	28	mddev_t *mddev;
	29	mirror_info_t *mirrors;
	30	int raid_disks;
1da177e4 LT	31	int last_used;
	32	sector_t next_seq_sect;
	33	spinlock_t device_lock;
	34
	35	struct list_head retry_list;
191ea9b2 N	36	/* queue pending writes and submit them on unplug */
191ea9b2 N	37	struct bio_list pending_bio_list;
191ea9b2	38
1da177e4 LT	39	/* for use when syncing mirrors: */
	40
	41	spinlock_t resync_lock;
191ea9b2	42	int nr_pending;
17999be4	43	int nr_waiting;
ddaf22ab	44	int nr_queued;
191ea9b2	45	int barrier;
1da177e4	46	sector_t next_resync;
191ea9b2 N	47	int fullsync; /* set to 1 if a full sync is needed,
	48	* (fresh device added).
	49	* Cleared when a sync completes.
	50	*/
1da177e4	51
17999be4	52	wait_queue_head_t wait_barrier;
1da177e4 LT	53
	54	struct pool_info *poolinfo;
	55
ddaf22ab N	56	struct page *tmppage;
ddaf22ab N	57
1da177e4 LT	58	mempool_t *r1bio_pool;
1da177e4 LT	59	mempool_t *r1buf_pool;
709ae487 N	60
	61	/* When taking over an array from a different personality, we store
	62	* the new thread here until we fully activate the array.
	63	*/
	64	struct mdk_thread_s *thread;
1da177e4 LT	65	};
	66
	67	typedef struct r1_private_data_s conf_t;
	68
1da177e4 LT	69	/*
	70	* this is our 'private' RAID1 bio.
	71	*
	72	* it contains information about what kind of IO operations were started
	73	* for this RAID1 operation, and about their status:
	74	*/
	75
	76	struct r1bio_s {
	77	atomic_t remaining; /* 'have we finished' count,
	78	* used from IRQ handlers
	79	*/
4b6d287f N	80	atomic_t behind_remaining; /* number of write-behind ios remaining
	81	* in this BehindIO request
	82	*/
1da177e4 LT	83	sector_t sector;
	84	int sectors;
	85	unsigned long state;
	86	mddev_t *mddev;
	87	/*
	88	* original bio going to /dev/mdx
	89	*/
	90	struct bio *master_bio;
	91	/*
	92	* if the IO is in READ direction, then this is where we read
	93	*/
	94	int read_disk;
	95
	96	struct list_head retry_list;
191ea9b2	97	struct bitmap_update *bitmap_update;
1da177e4 LT	98	/*
	99	* if the IO is in WRITE direction, then multiple bios are used.
	100	* We choose the number when they are allocated.
	101	*/
	102	struct bio *bios[0];
191ea9b2	103	/* DO NOT PUT ANY NEW FIELDS HERE - bios array is contiguously alloced*/
1da177e4 LT	104	};
1da177e4 LT	105
cf30a473 N	106	/* when we get a read error on a read-only array, we redirect to another
	107	* device without failing the first device, or trying to over-write to
	108	* correct the read error. To keep track of bad blocks on a per-bio
	109	* level, we store IO_BLOCKED in the appropriate 'bios' pointer
	110	*/
	111	#define IO_BLOCKED ((struct bio*)1)
	112
1da177e4 LT	113	/* bits for r1bio.state */
	114	#define R1BIO_Uptodate 0
	115	#define R1BIO_IsSync 1
191ea9b2	116	#define R1BIO_Degraded 2
a9701a30	117	#define R1BIO_BehindIO 3
4b6d287f N	118	/* For write-behind requests, we call bi_end_io when
	119	* the last non-write-behind device completes, providing
	120	* any write was successful. Otherwise we call when
	121	* any write-behind write succeeds, otherwise we call
	122	* with failure when last write completes (and all failed).
	123	* Record that bi_end_io was called with this flag...
	124	*/
9e71f9c8	125	#define R1BIO_Returned 6
4b6d287f	126
1da177e4	127	#endif