A 2-device raid5 array can now be converted to raid1. Signed-off-by: NeilBrown <neilb@suse.de>
		
			
				
	
	
		
			131 lines
		
	
	
	
		
			3.3 KiB
			
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			131 lines
		
	
	
	
		
			3.3 KiB
			
		
	
	
	
		
			C
		
	
	
	
	
	
#ifndef _RAID1_H
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#define _RAID1_H
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typedef struct mirror_info mirror_info_t;
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struct mirror_info {
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	mdk_rdev_t	*rdev;
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	sector_t	head_position;
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};
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/*
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 * memory pools need a pointer to the mddev, so they can force an unplug
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 * when memory is tight, and a count of the number of drives that the
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 * pool was allocated for, so they know how much to allocate and free.
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 * mddev->raid_disks cannot be used, as it can change while a pool is active
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 * These two datums are stored in a kmalloced struct.
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 */
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struct pool_info {
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	mddev_t *mddev;
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	int	raid_disks;
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};
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typedef struct r1bio_s r1bio_t;
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struct r1_private_data_s {
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	mddev_t			*mddev;
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	mirror_info_t		*mirrors;
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	int			raid_disks;
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	int			last_used;
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	sector_t		next_seq_sect;
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	spinlock_t		device_lock;
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	struct list_head	retry_list;
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	/* queue pending writes and submit them on unplug */
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	struct bio_list		pending_bio_list;
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	/* queue of writes that have been unplugged */
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	struct bio_list		flushing_bio_list;
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	/* for use when syncing mirrors: */
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	spinlock_t		resync_lock;
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	int			nr_pending;
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	int			nr_waiting;
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	int			nr_queued;
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	int			barrier;
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	sector_t		next_resync;
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	int			fullsync;  /* set to 1 if a full sync is needed,
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					    * (fresh device added).
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					    * Cleared when a sync completes.
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					    */
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	wait_queue_head_t	wait_barrier;
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	struct pool_info	*poolinfo;
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	struct page		*tmppage;
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	mempool_t *r1bio_pool;
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	mempool_t *r1buf_pool;
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	/* When taking over an array from a different personality, we store
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	 * the new thread here until we fully activate the array.
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	 */
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	struct mdk_thread_s	*thread;
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};
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typedef struct r1_private_data_s conf_t;
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/*
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 * this is our 'private' RAID1 bio.
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 *
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 * it contains information about what kind of IO operations were started
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 * for this RAID1 operation, and about their status:
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 */
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struct r1bio_s {
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	atomic_t		remaining; /* 'have we finished' count,
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					    * used from IRQ handlers
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					    */
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	atomic_t		behind_remaining; /* number of write-behind ios remaining
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						 * in this BehindIO request
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						 */
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	sector_t		sector;
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	int			sectors;
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	unsigned long		state;
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	mddev_t			*mddev;
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	/*
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	 * original bio going to /dev/mdx
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	 */
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	struct bio		*master_bio;
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	/*
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	 * if the IO is in READ direction, then this is where we read
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	 */
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	int			read_disk;
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	struct list_head	retry_list;
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	struct bitmap_update	*bitmap_update;
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	/*
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	 * if the IO is in WRITE direction, then multiple bios are used.
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	 * We choose the number when they are allocated.
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	 */
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	struct bio		*bios[0];
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	/* DO NOT PUT ANY NEW FIELDS HERE - bios array is contiguously alloced*/
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};
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/* when we get a read error on a read-only array, we redirect to another
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 * device without failing the first device, or trying to over-write to
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 * correct the read error.  To keep track of bad blocks on a per-bio
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 * level, we store IO_BLOCKED in the appropriate 'bios' pointer
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 */
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#define IO_BLOCKED ((struct bio*)1)
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/* bits for r1bio.state */
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#define	R1BIO_Uptodate	0
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#define	R1BIO_IsSync	1
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#define	R1BIO_Degraded	2
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#define	R1BIO_BehindIO	3
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#define	R1BIO_Barrier	4
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#define R1BIO_BarrierRetry 5
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/* For write-behind requests, we call bi_end_io when
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 * the last non-write-behind device completes, providing
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 * any write was successful.  Otherwise we call when
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 * any write-behind write succeeds, otherwise we call
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 * with failure when last write completes (and all failed).
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 * Record that bi_end_io was called with this flag...
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 */
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#define	R1BIO_Returned 6
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#endif
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