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#ifndef _RAID5_H
#define _RAID5_H
#ifdef __KERNEL__
#include <linux/md.h>
#include <asm/atomic.h>
struct disk_info {
kdev_t dev;
int operational;
int number;
int raid_disk;
int write_only;
int spare;
};
struct stripe_head {
struct stripe_head *hash_next, **hash_pprev; /* hash pointers */
struct stripe_head *free_next; /* pool of free sh's */
struct buffer_head *buffer_pool; /* pool of free buffers */
struct buffer_head *bh_pool; /* pool of free bh's */
struct raid5_data *raid_conf;
struct buffer_head *bh_old[MD_SB_DISKS]; /* disk image */
struct buffer_head *bh_new[MD_SB_DISKS]; /* buffers of the MD device (present in buffer cache) */
struct buffer_head *bh_copy[MD_SB_DISKS]; /* copy on write of bh_new (bh_new can change from under us) */
struct buffer_head *bh_req[MD_SB_DISKS]; /* copy of bh_new (only the buffer heads), queued to the lower levels */
int cmd_new[MD_SB_DISKS]; /* READ/WRITE for new */
int new[MD_SB_DISKS]; /* buffer added since the last handle_stripe() */
unsigned long sector; /* sector of this row */
int size; /* buffers size */
int pd_idx; /* parity disk index */
int nr_pending; /* nr of pending cmds */
unsigned long state; /* state flags */
int cmd; /* stripe cmd */
int count; /* nr of waiters */
int write_method; /* reconstruct-write / read-modify-write */
int phase; /* PHASE_BEGIN, ..., PHASE_COMPLETE */
wait_queue_head_t wait; /* processes waiting for this stripe */
};
/*
* Phase
*/
#define PHASE_BEGIN 0
#define PHASE_READ_OLD 1
#define PHASE_WRITE 2
#define PHASE_READ 3
#define PHASE_COMPLETE 4
/*
* Write method
*/
#define METHOD_NONE 0
#define RECONSTRUCT_WRITE 1
#define READ_MODIFY_WRITE 2
/*
* Stripe state
*/
#define STRIPE_LOCKED 0
#define STRIPE_ERROR 1
/*
* Stripe commands
*/
#define STRIPE_NONE 0
#define STRIPE_WRITE 1
#define STRIPE_READ 2
struct raid5_data {
struct stripe_head **stripe_hashtbl;
struct md_dev *mddev;
struct md_thread *thread, *resync_thread;
struct disk_info disks[MD_SB_DISKS];
struct disk_info *spare;
int buffer_size;
int chunk_size, level, algorithm;
int raid_disks, working_disks, failed_disks;
int sector_count;
unsigned long next_sector;
atomic_t nr_handle;
struct stripe_head *next_free_stripe;
int nr_stripes;
int resync_parity;
int max_nr_stripes;
int clock;
int nr_hashed_stripes;
int nr_locked_stripes;
int nr_pending_stripes;
int nr_cached_stripes;
/*
* Free stripes pool
*/
int nr_free_sh;
struct stripe_head *free_sh_list;
wait_queue_head_t wait_for_stripe;
};
#endif
/*
* Our supported algorithms
*/
#define ALGORITHM_LEFT_ASYMMETRIC 0
#define ALGORITHM_RIGHT_ASYMMETRIC 1
#define ALGORITHM_LEFT_SYMMETRIC 2
#define ALGORITHM_RIGHT_SYMMETRIC 3
#endif
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