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1/* SPDX-License-Identifier: GPL-2.0 */2/*3 * bitmap.h: Copyright (C) Peter T. Breuer (ptb@ot.uc3m.es) 20034 *5 * additions: Copyright (C) 2003-2004, Paul Clements, SteelEye Technology, Inc.6 */7#ifndef BITMAP_H8#define BITMAP_H 19 10#define BITMAP_MAGIC 0x6d74696211 12typedef __u16 bitmap_counter_t;13#define COUNTER_BITS 1614#define COUNTER_BIT_SHIFT 415#define COUNTER_BYTE_SHIFT (COUNTER_BIT_SHIFT - 3)16 17#define NEEDED_MASK ((bitmap_counter_t) (1 << (COUNTER_BITS - 1)))18#define RESYNC_MASK ((bitmap_counter_t) (1 << (COUNTER_BITS - 2)))19#define COUNTER_MAX ((bitmap_counter_t) RESYNC_MASK - 1)20 21/* use these for bitmap->flags and bitmap->sb->state bit-fields */22enum bitmap_state {23 BITMAP_STALE = 1, /* the bitmap file is out of date or had -EIO */24 BITMAP_WRITE_ERROR = 2, /* A write error has occurred */25 BITMAP_HOSTENDIAN =15,26};27 28/* the superblock at the front of the bitmap file -- little endian */29typedef struct bitmap_super_s {30 __le32 magic; /* 0 BITMAP_MAGIC */31 __le32 version; /* 4 the bitmap major for now, could change... */32 __u8 uuid[16]; /* 8 128 bit uuid - must match md device uuid */33 __le64 events; /* 24 event counter for the bitmap (1)*/34 __le64 events_cleared;/*32 event counter when last bit cleared (2) */35 __le64 sync_size; /* 40 the size of the md device's sync range(3) */36 __le32 state; /* 48 bitmap state information */37 __le32 chunksize; /* 52 the bitmap chunk size in bytes */38 __le32 daemon_sleep; /* 56 seconds between disk flushes */39 __le32 write_behind; /* 60 number of outstanding write-behind writes */40 __le32 sectors_reserved; /* 64 number of 512-byte sectors that are41 * reserved for the bitmap. */42 __le32 nodes; /* 68 the maximum number of nodes in cluster. */43 __u8 cluster_name[64]; /* 72 cluster name to which this md belongs */44 __u8 pad[256 - 136]; /* set to zero */45} bitmap_super_t;46 47/* notes:48 * (1) This event counter is updated before the eventcounter in the md superblock49 * When a bitmap is loaded, it is only accepted if this event counter is equal50 * to, or one greater than, the event counter in the superblock.51 * (2) This event counter is updated when the other one is *if*and*only*if* the52 * array is not degraded. As bits are not cleared when the array is degraded,53 * this represents the last time that any bits were cleared.54 * If a device is being added that has an event count with this value or55 * higher, it is accepted as conforming to the bitmap.56 * (3)This is the number of sectors represented by the bitmap, and is the range that57 * resync happens across. For raid1 and raid5/6 it is the size of individual58 * devices. For raid10 it is the size of the array.59 */60 61struct md_bitmap_stats {62 u64 events_cleared;63 int behind_writes;64 bool behind_wait;65 66 unsigned long missing_pages;67 unsigned long file_pages;68 unsigned long sync_size;69 unsigned long pages;70 struct file *file;71};72 73struct bitmap_operations {74 bool (*enabled)(struct mddev *mddev);75 int (*create)(struct mddev *mddev, int slot);76 int (*resize)(struct mddev *mddev, sector_t blocks, int chunksize,77 bool init);78 79 int (*load)(struct mddev *mddev);80 void (*destroy)(struct mddev *mddev);81 void (*flush)(struct mddev *mddev);82 void (*write_all)(struct mddev *mddev);83 void (*dirty_bits)(struct mddev *mddev, unsigned long s,84 unsigned long e);85 void (*unplug)(struct mddev *mddev, bool sync);86 void (*daemon_work)(struct mddev *mddev);87 void (*wait_behind_writes)(struct mddev *mddev);88 89 int (*startwrite)(struct mddev *mddev, sector_t offset,90 unsigned long sectors, bool behind);91 void (*endwrite)(struct mddev *mddev, sector_t offset,92 unsigned long sectors, bool success, bool behind);93 bool (*start_sync)(struct mddev *mddev, sector_t offset,94 sector_t *blocks, bool degraded);95 void (*end_sync)(struct mddev *mddev, sector_t offset, sector_t *blocks);96 void (*cond_end_sync)(struct mddev *mddev, sector_t sector, bool force);97 void (*close_sync)(struct mddev *mddev);98 99 void (*update_sb)(void *data);100 int (*get_stats)(void *data, struct md_bitmap_stats *stats);101 102 void (*sync_with_cluster)(struct mddev *mddev,103 sector_t old_lo, sector_t old_hi,104 sector_t new_lo, sector_t new_hi);105 void *(*get_from_slot)(struct mddev *mddev, int slot);106 int (*copy_from_slot)(struct mddev *mddev, int slot, sector_t *lo,107 sector_t *hi, bool clear_bits);108 void (*set_pages)(void *data, unsigned long pages);109 void (*free)(void *data);110};111 112/* the bitmap API */113void mddev_set_bitmap_ops(struct mddev *mddev);114 115#endif116