Quelle  sb-members_format.h   Sprache: C

/* SPDX-License-Identifier: GPL-2.0 */
#ifndef _BCACHEFS_SB_MEMBERS_FORMAT_H
#define _BCACHEFS_SB_MEMBERS_FORMAT_H

/*
 * We refer to members with bitmasks in various places - but we need to get rid
 * of this limit:
 */
#define BCH_SB_MEMBERS_MAX  64

/*
 * Sentinal value - indicates a device that does not exist
 */
#define BCH_SB_MEMBER_INVALID  255

#define BCH_SB_MEMBER_DELETED_UUID     \
 UUID_INIT(0xffffffff, 0xffff, 0xffff,    \
    0xd9, 0x6a, 0x60, 0xcf, 0x80, 0x3d, 0xf7, 0xef)

#define BCH_MIN_NR_NBUCKETS (1 << 6)

#define BCH_IOPS_MEASUREMENTS()   \
 x(seqread, 0)   \
 x(seqwrite, 1)   \
 x(randread, 2)   \
 x(randwrite, 3)

enum bch_iops_measurement {
#define x(t, n) BCH_IOPS_##t = n,
 BCH_IOPS_MEASUREMENTS()
#undef x
 BCH_IOPS_NR
};

#define BCH_MEMBER_ERROR_TYPES()  \
 x(read,  0)   \
 x(write, 1)   \
 x(checksum, 2)

enum bch_member_error_type {
#define x(t, n) BCH_MEMBER_ERROR_##t = n,
 BCH_MEMBER_ERROR_TYPES()
#undef x
 BCH_MEMBER_ERROR_NR
};

struct bch_member {
 __uuid_t  uuid;
 __le64   nbuckets; /* device size */
 __le16   first_bucket;   /* index of first bucket used */
 __le16   bucket_size; /* sectors */
 __u8   btree_bitmap_shift;
 __u8   pad[3];
 __le64   last_mount; /* time_t */

 __le64   flags;
 __le32   iops[4];
 __le64   errors[BCH_MEMBER_ERROR_NR];
 __le64   errors_at_reset[BCH_MEMBER_ERROR_NR];
 __le64   errors_reset_time;
 __le64   seq;
 __le64   btree_allocated_bitmap;
 /*
 * On recovery from a clean shutdown we don't normally read the journal,
 * but we still want to resume writing from where we left off so we
 * don't overwrite more than is necessary, for list journal debugging:
 */
 __le32   last_journal_bucket;
 __le32   last_journal_bucket_offset;
};

/*
 * btree_allocated_bitmap can represent sector addresses of a u64: it itself has
 * 64 elements, so 64 - ilog2(64)
 */
#define BCH_MI_BTREE_BITMAP_SHIFT_MAX 58

/*
 * This limit comes from the bucket_gens array - it's a single allocation, and
 * kernel allocation are limited to INT_MAX
 */
#define BCH_MEMBER_NBUCKETS_MAX (INT_MAX - 64)

#define BCH_MEMBER_V1_BYTES 56

LE16_BITMASK(BCH_MEMBER_BUCKET_SIZE, struct bch_member, bucket_size,  0, 16)
LE64_BITMASK(BCH_MEMBER_STATE,  struct bch_member, flags,  0,  4)
/* 4-14 unused, was TIER, HAS_(META)DATA, REPLACEMENT */
LE64_BITMASK(BCH_MEMBER_DISCARD, struct bch_member, flags, 14, 15)
LE64_BITMASK(BCH_MEMBER_DATA_ALLOWED, struct bch_member, flags, 15, 20)
LE64_BITMASK(BCH_MEMBER_GROUP,  struct bch_member, flags, 20, 28)
LE64_BITMASK(BCH_MEMBER_DURABILITY, struct bch_member, flags, 28, 30)
LE64_BITMASK(BCH_MEMBER_FREESPACE_INITIALIZED,
     struct bch_member, flags, 30, 31)
LE64_BITMASK(BCH_MEMBER_RESIZE_ON_MOUNT,
     struct bch_member, flags, 31, 32)

#if 0
LE64_BITMASK(BCH_MEMBER_NR_READ_ERRORS, struct bch_member, flags[1], 0,  20);
LE64_BITMASK(BCH_MEMBER_NR_WRITE_ERRORS,struct bch_member, flags[1], 20, 40);
#endif

#define BCH_MEMBER_STATES()   \
 x(rw,  0)   \
 x(ro,  1)   \
 x(failed, 2)   \
 x(spare, 3)

enum bch_member_state {
#define x(t, n) BCH_MEMBER_STATE_##t = n,
 BCH_MEMBER_STATES()
#undef x
 BCH_MEMBER_STATE_NR
};

struct bch_sb_field_members_v1 {
 struct bch_sb_field field;
 struct bch_member _members[]; //Members are now variable size
};

struct bch_sb_field_members_v2 {
 struct bch_sb_field field;
 __le16   member_bytes; //size of single member entry
 u8   pad[6];
 struct bch_member _members[];
};

#endif /* _BCACHEFS_SB_MEMBERS_FORMAT_H */