/* SPDX-License-Identifier: GPL-2.0 */
/*
* bitmap.h: Copyright (C) Peter T. Breuer ([email protected]) 2003
*
* additions: Copyright (C) 2003-2004, Paul Clements, SteelEye Technology, Inc.
*/
#ifndef BITMAP_H
#define BITMAP_H 1
#define BITMAP_MAGIC 0x6d746962
typedef __u16 bitmap_counter_t;
#define COUNTER_BITS 16
#define COUNTER_BIT_SHIFT 4
#define COUNTER_BYTE_SHIFT (COUNTER_BIT_SHIFT - 3)
#define NEEDED_MASK ((bitmap_counter_t) (1 << (COUNTER_BITS - 1)))
#define RESYNC_MASK ((bitmap_counter_t) (1 << (COUNTER_BITS - 2)))
#define COUNTER_MAX ((bitmap_counter_t) RESYNC_MASK - 1)
/* use these for bitmap->flags and bitmap->sb->state bit-fields */
enum bitmap_state {
BITMAP_STALE = 1, /* the bitmap file is out of date or had -EIO */
BITMAP_WRITE_ERROR = 2, /* A write error has occurred */
BITMAP_HOSTENDIAN =15,
};
/* the superblock at the front of the bitmap file -- little endian */
typedef struct bitmap_super_s {
__le32 magic; /* 0 BITMAP_MAGIC */
__le32 version; /* 4 the bitmap major for now, could change... */
__u8 uuid[16]; /* 8 128 bit uuid - must match md device uuid */
__le64 events; /* 24 event counter for the bitmap (1)*/
__le64 events_cleared;/*32 event counter when last bit cleared (2) */
__le64 sync_size; /* 40 the size of the md device's sync range(3) */
__le32 state; /* 48 bitmap state information */
__le32 chunksize; /* 52 the bitmap chunk size in bytes */
__le32 daemon_sleep; /* 56 seconds between disk flushes */
__le32 write_behind; /* 60 number of outstanding write-behind writes */
__le32 sectors_reserved; /* 64 number of 512-byte sectors that are
* reserved for the bitmap. */
__le32 nodes; /* 68 the maximum number of nodes in cluster. */
__u8 cluster_name[64]; /* 72 cluster name to which this md belongs */
__u8 pad[256 - 136]; /* set to zero */
} bitmap_super_t;
/* notes:
* (1) This event counter is updated before the eventcounter in the md superblock
* When a bitmap is loaded, it is only accepted if this event counter is equal
* to, or one greater than, the event counter in the superblock.
* (2) This event counter is updated when the other one is *if*and*only*if* the
* array is not degraded. As bits are not cleared when the array is degraded,
* this represents the last time that any bits were cleared.
* If a device is being added that has an event count with this value or
* higher, it is accepted as conforming to the bitmap.
* (3)This is the number of sectors represented by the bitmap, and is the range that
* resync happens across. For raid1 and raid5/6 it is the size of individual
* devices. For raid10 it is the size of the array.
*/
struct md_bitmap_stats {
u64 events_cleared;
int behind_writes;
bool behind_wait;
unsigned long missing_pages;
unsigned long file_pages;
unsigned long sync_size;
unsigned long pages;
struct file *file;
};
struct bitmap_operations {
bool (*enabled)(struct mddev *mddev);
int (*create)(struct mddev *mddev, int slot);
int (*resize)(struct mddev *mddev, sector_t blocks, int chunksize,
bool init);
int (*load)(struct mddev *mddev);
void (*destroy)(struct mddev *mddev);
void (*flush)(struct mddev *mddev);
void (*write_all)(struct mddev *mddev);
void (*dirty_bits)(struct mddev *mddev, unsigned long s,
unsigned long e);
void (*unplug)(struct mddev *mddev, bool sync);
void (*daemon_work)(struct mddev *mddev);
void (*wait_behind_writes)(struct mddev *mddev);
int (*startwrite)(struct mddev *mddev, sector_t offset,
unsigned long sectors, bool behind);
void (*endwrite)(struct mddev *mddev, sector_t offset,
unsigned long sectors, bool success, bool behind);
bool (*start_sync)(struct mddev *mddev, sector_t offset,
sector_t *blocks, bool degraded);
void (*end_sync)(struct mddev *mddev, sector_t offset, sector_t *blocks);
void (*cond_end_sync)(struct mddev *mddev, sector_t sector, bool force);
void (*close_sync)(struct mddev *mddev);
void (*update_sb)(void *data);
int (*get_stats)(void *data, struct md_bitmap_stats *stats);
void (*sync_with_cluster)(struct mddev *mddev,
sector_t old_lo, sector_t old_hi,
sector_t new_lo, sector_t new_hi);
void *(*get_from_slot)(struct mddev *mddev, int slot);
int (*copy_from_slot)(struct mddev *mddev, int slot, sector_t *lo,
sector_t *hi, bool clear_bits);
void (*set_pages)(void *data, unsigned long pages);
void (*free)(void *data);
};
/* the bitmap API */
void mddev_set_bitmap_ops(struct mddev *mddev);
#endif
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