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;; Copyright (C) KolibriOS team 2013-2014. All rights reserved. ;;

;; Distributed under terms of the GNU General Public License    ;;

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$Revision: 4850 $

; from stat.h

; distinguish file types

S_IFMT      = 0170000o  ; These bits determine file type.

S_IFDIR     = 0040000o  ; Directory.

S_IFCHR     = 0020000o  ; Character device.

S_IFBLK     = 0060000o  ; Block device.

S_IFREG     = 0100000o  ; Regular file.

S_IFIFO     = 0010000o  ; FIFO.

S_IFLNK     = 0120000o  ; Symbolic link.

S_IFSOCK    = 0140000o  ; Socket.

; end stat.h

; XFS null constant: empty fields must be all ones, not zeros!

XFS_NULL                = -1

; static sector numbers

XFS_SECT_SB             = 0

XFS_SECT_AGF            = 1

XFS_SECT_AGI            = 2

XFS_SECT_AGFL           = 3

; signatures of file system structures

; 'string' numbers are treated by fasm as big endian

XFS_SB_MAGIC            = 'XFSB'

XFS_AGF_MAGIC           = 'XAGF'

XFS_AGI_MAGIC           = 'XAGI'

XFS_ABTB_MAGIC          = 'ABTB'

XFS_ABTC_MAGIC          = 'ABTC'

XFS_IBT_MAGIC           = 'IABT'

XFS_DINODE_MAGIC        = 'IN'

XFS_BMAP_MAGIC          = 'BMAP'

XFS_DA_NODE_MAGIC       = 0xbefe        ; those are little endian here

XFS_ATTR_LEAF_MAGIC     = 0xeefb        ; but big endian in docs

XFS_DIR2_LEAF1_MAGIC    = 0xf1d2        ; pay attention!

XFS_DIR2_LEAFN_MAGIC    = 0xffd2        ;

XFS_DIR2_BLOCK_MAGIC    = 'XD2B'

XFS_DIR2_DATA_MAGIC     = 'XD2D'

XFS_DIR2_FREE_MAGIC     = 'XD2F'

XFS_DQUOT_MAGIC         = 'DQ'

; bitfield lengths for packed extent

; MSB to LSB / left to right

BMBT_EXNTFLAG_BITLEN    =  1

BMBT_STARTOFF_BITLEN    = 54

BMBT_STARTBLOCK_BITLEN  = 52

BMBT_BLOCKCOUNT_BITLEN  = 21

; those constants are taken from linux source (xfs_dir2_leaf.h)

; they are magic infile offsets for directories

XFS_DIR2_DATA_ALIGN_LOG = 3     ; i.e., 8 bytes

XFS_DIR2_LEAF_SPACE     = 1

XFS_DIR2_SPACE_SIZE     = (1 SHL (32 + XFS_DIR2_DATA_ALIGN_LOG))

XFS_DIR2_LEAF_OFFSET    = (XFS_DIR2_LEAF_SPACE * XFS_DIR2_SPACE_SIZE)

XFS_DIR2_FREE_SPACE     = 2

XFS_DIR2_SPACE_SIZE     = (1 SHL (32 + XFS_DIR2_DATA_ALIGN_LOG))

XFS_DIR2_FREE_OFFSET    = (XFS_DIR2_FREE_SPACE * XFS_DIR2_SPACE_SIZE)

; data section magic constants for directories (xfs_dir2_data.h)

XFS_DIR2_DATA_FD_COUNT  = 3

XFS_DIR2_DATA_FREE_TAG  = 0xffff

; valid inode formats

; enum xfs_dinode_fmt (xfs_dinode.h)

XFS_DINODE_FMT_DEV      = 0     ; xfs_dev_t

XFS_DINODE_FMT_LOCAL    = 1     ; one inode is enough (shortdir)

XFS_DINODE_FMT_EXTENTS  = 2     ; one or more extents (leafdir, nodedir, regular files)

XFS_DINODE_FMT_BTREE    = 3     ; highly fragmented files or really huge directories

XFS_DINODE_FMT_UUID     = 4     ; uuid_t

; size of the unlinked inode hash table in the agi

XFS_AGI_UNLINKED_BUCKETS = 64

; possible extent states

; enum xfs_exntst_t (xfs_bmap_btree.h)

XFS_EXT_NORM            = 0

XFS_EXT_UNWRITTEN       = 1

XFS_EXT_DMAPI_OFFLINE   = 2

XFS_EXT_INVALID         = 3

; values for inode core flags / di_flags (xfs_dinode.h)

XFS_DIFLAG_REALTIME_BIT     =  0        ; file's blocks come from rt area

XFS_DIFLAG_PREALLOC_BIT     =  1        ; file space has been preallocated

XFS_DIFLAG_NEWRTBM_BIT      =  2        ; for rtbitmap inode, new format

XFS_DIFLAG_IMMUTABLE_BIT    =  3        ; inode is immutable

XFS_DIFLAG_APPEND_BIT       =  4        ; inode is append-only

XFS_DIFLAG_SYNC_BIT         =  5        ; inode is written synchronously

XFS_DIFLAG_NOATIME_BIT      =  6        ; do not update atime

XFS_DIFLAG_NODUMP_BIT       =  7        ; do not dump

XFS_DIFLAG_RTINHERIT_BIT    =  8        ; create with realtime bit set

XFS_DIFLAG_PROJINHERIT_BIT  =  9        ; create with parents projid

XFS_DIFLAG_NOSYMLINKS_BIT   = 10        ; disallow symlink creation

XFS_DIFLAG_EXTSIZE_BIT      = 11        ; inode extent size allocator hint

XFS_DIFLAG_EXTSZINHERIT_BIT = 12        ; inherit inode extent size

XFS_DIFLAG_NODEFRAG_BIT     = 13        ; do not reorganize/defragment

XFS_DIFLAG_FILESTREAM_BIT   = 14        ; use filestream allocator

XFS_DIFLAG_REALTIME         = (1 SHL XFS_DIFLAG_REALTIME_BIT)

XFS_DIFLAG_PREALLOC         = (1 SHL XFS_DIFLAG_PREALLOC_BIT)

XFS_DIFLAG_NEWRTBM          = (1 SHL XFS_DIFLAG_NEWRTBM_BIT)

XFS_DIFLAG_IMMUTABLE        = (1 SHL XFS_DIFLAG_IMMUTABLE_BIT)

XFS_DIFLAG_APPEND           = (1 SHL XFS_DIFLAG_APPEND_BIT)

XFS_DIFLAG_SYNC             = (1 SHL XFS_DIFLAG_SYNC_BIT)

XFS_DIFLAG_NOATIME          = (1 SHL XFS_DIFLAG_NOATIME_BIT)

XFS_DIFLAG_NODUMP           = (1 SHL XFS_DIFLAG_NODUMP_BIT)

XFS_DIFLAG_RTINHERIT        = (1 SHL XFS_DIFLAG_RTINHERIT_BIT)

XFS_DIFLAG_PROJINHERIT      = (1 SHL XFS_DIFLAG_PROJINHERIT_BIT)

XFS_DIFLAG_NOSYMLINKS       = (1 SHL XFS_DIFLAG_NOSYMLINKS_BIT)

XFS_DIFLAG_EXTSIZE          = (1 SHL XFS_DIFLAG_EXTSIZE_BIT)

XFS_DIFLAG_EXTSZINHERIT     = (1 SHL XFS_DIFLAG_EXTSZINHERIT_BIT)

XFS_DIFLAG_NODEFRAG         = (1 SHL XFS_DIFLAG_NODEFRAG_BIT)

XFS_DIFLAG_FILESTREAM       = (1 SHL XFS_DIFLAG_FILESTREAM_BIT)

; superblock _ondisk_ structure (xfs_sb.h)

; this is _not_ the partition structure

; for XFS partition structure see XFS below

struct xfs_sb

        sb_magicnum     dd ?    ; signature, must be XFS_SB_MAGIC

        sb_blocksize    dd ?    ; block is the minimal file system unit, in bytes

        sb_dblocks      dq ?    ; number of data blocks

        sb_rblocks      dq ?    ; number of realtime blocks (not supported yet!)

        sb_rextents     dq ?    ; number of realtime extents (not supported yet!)

        sb_uuid         rb 16   ; file system unique identifier

        sb_logstart     dq ?    ; starting block of log (for internal journal; journals on separate devices are not supported!)

        sb_rootino      dq ?    ; root inode number

        sb_rbmino       dq ?    ; bitmap inode for realtime extents (ignored)

        sb_rsumino      dq ?    ; summary inode for rt bitmap (ignored)

        sb_rextsize     dd ?    ; realtime extent size, blocks

        sb_agblocks     dd ?    ; size of an allocation group (the last one may be smaller!)

        sb_agcount      dd ?    ; number of allocation groups

        sb_rbmblocks    dd ?    ; number of rt bitmap blocks

        sb_logblocks    dd ?    ; number of log blocks

        sb_versionnum   dw ?    ; header version == XFS_SB_VERSION

        sb_sectsize     dw ?    ; volume sector size in bytes (only 512B sectors are supported)

        sb_inodesize    dw ?    ; inode size, bytes

        sb_inopblock    dw ?    ; inodes per block

        sb_fname        rb 12   ; inodes per block (aka label)

        sb_blocklog     db ?    ; log2 of sb_blocksize

        sb_sectlog      db ?    ; log2 of sb_blocksize

        sb_inodelog     db ?    ; log2 of sb_inodesize

        sb_inopblog     db ?    ; log2 of sb_inopblock

        sb_agblklog     db ?    ; log2 of sb_agblocks (rounded up!)

        sb_rextslog     db ?    ; log2 of sb_rextents

        sb_inprogress   db ?    ; mkfs is in progress, don't mount

        sb_imax_pct     db ?    ; max % of fs for inode space

        ; statistics

        sb_icount       dq ?    ; allocated inodes

        sb_ifree        dq ?    ; free inodes

        sb_fdblocks     dq ?    ; free data blocks

        sb_frextents    dq ?    ; free realtime extents

        sb_uquotino     dq ?    ; user quota inode

        sb_gquotino     dq ?    ; group quota inode

        sb_qflags       dw ?    ; quota flags

        sb_flags        db ?    ; misc. flags

        sb_shared_vn    db ?    ; shared version number

        sb_inoalignmt   dd ?    ; inode chunk alignment, fsblocks

        sb_unit         dd ?    ; stripe or raid unit

        sb_width        dd ?    ; stripe or raid width

        sb_dirblklog    db ?    ; log2 of dir block size (fsbs)

        sb_logsectlog   db ?    ; log2 of the log sector size

        sb_logsectsize  dw ?    ; sector size for the log, bytes

        sb_logsunit     dd ?    ; stripe unit size for the log

        sb_features2    dd ?    ; additional feature bits

ends

; allocation group inode (xfs_ag.h)

struct xfs_agi

        agi_magicnum    dd ?    ; magic number == XFS_AGI_MAGIC

        agi_versionnum  dd ?    ; header version == XFS_AGI_VERSION

        agi_seqno       dd ?    ; sequence number starting from 0

        agi_length      dd ?    ; size in blocks of a.g.

        agi_count       dd ?    ; count of allocated inodes

        agi_root        dd ?    ; root of inode btree

        agi_level       dd ?    ; levels in inode btree

        agi_freecount   dd ?    ; number of free inodes

        agi_newino      dd ?    ; new inode just allocated

        agi_dirino      dd ?    ; last directory inode chunk

        agi_unlinked    rd XFS_AGI_UNLINKED_BUCKETS     ; Hash table of inodes which have been unlinked but are still being referenced

ends

; superblock structure of b+tree node/leaf (same structure, bb_level matters)

struct xfs_btree_sblock

        bb_magic        dd ?

        bb_level        dw ?    ; distinguishes nodeds and leaves

        bb_numrecs      dw ?

        bb_leftsib      dd ?

        bb_rightsib     dd ?

ends

; record of b+tree inode

struct xfs_inobt_rec

        ir_startino     dd ?

        ir_freecount    dd ?

        ir_free         dq ?

ends

; structure to store create, access and modification time in inode core

struct xfs_timestamp

        t_sec           dd ?

        t_nsec          dd ?    ; nanoseconds

ends

; inode core structure: basic information about file

struct xfs_dinode_core

        di_magic        dw ?            ; inode magic = XFS_DINODE_MAGIC

        di_mode         dw ?            ; mode and type of file

        di_version      db ?            ; inode version

        di_format       db ?            ; format of di_c data

        di_onlink       dw ?            ; old number of links to file

        di_uid          dd ?            ; owner's user id

        di_gid          dd ?            ; owner's group id

        di_nlink        dd ?            ; number of links to file

        di_projid       dw ?            ; owner's project id

        di_pad          rb 8            ; unused, zeroed space

        di_flushiter    dw ?            ; incremented on flush

        di_atime        xfs_timestamp   ; time last accessed

        di_mtime        xfs_timestamp   ; time last modified

        di_ctime        xfs_timestamp   ; time created/inode modified

        di_size         dq ?            ; number of bytes in file

        di_nblocks      dq ?            ; number of direct & btree blocks used

        di_extsize      dd ?            ; basic/minimum extent size for file

        di_nextents     dd ?            ; number of extents in data fork

        di_anextents    dw ?            ; number of extents in attribute fork

        di_forkoff      db ?            ; attr fork offs, <<3 for 64b align

        di_aformat      db ?            ; format of attr fork's data

        di_dmevmask     dd ?            ; DMIG event mask

        di_dmstate      dw ?            ; DMIG state info

        di_flags        dw ?            ; random flags, XFS_DIFLAG_...

        di_gen          dd ?            ; generation number

ends

; shortform dir header

struct xfs_dir2_sf_hdr

        count           db ?            ; the number of directory entries, used only if each inode number fits 4 bytes; zero otherwise

        i8count         db ?            ; the number of directory entries, used only when count is zero

        parent          dq ?            ; parent inode number: xfs_dir2_inou_t (4 or 8 bytes)

ends

; shortform dir entry

struct xfs_dir2_sf_entry

        namelen         db ?            ; actual name length (ASCII)

        offset          rb 2            ; saved offset

        name            db ?            ; name, variable size

;       inumber         dq ?            ; xfs_dir2_inou_t

ends

; active entry in a data block

; aligned to 8 bytes

; tag appears as the last 2 bytes

struct xfs_dir2_data_entry

        inumber         dq ?            ; inode number

        namelen         db ?            ; name length

        name            db ?            ; name bytes, no null

;       tag             dw ?            ; starting offset of us

ends

; unused entry in a data block

; aligned to 8 bytes

; tag appears as the last 2 bytes

struct xfs_dir2_data_unused

        freetag         dw ?            ; XFS_DIR2_DATA_FREE_TAG

        length          dw ?            ; total free length

;        tag             dw ?           ; starting offset of us

ends

; generic data entry

struct xfs_dir2_data_union

  union

        xentry          xfs_dir2_data_entry

        unused          xfs_dir2_data_unused

  ends

ends

; describe a free area in the data block

; the freespace will be formatted as a xfs_dir2_data_unused_t

struct xfs_dir2_data_free

        offset          dw ?            ; start of freespace

        length          dw ?            ; length of freespace

ends

; header for the data blocks

; always at the beginning of a directory-sized block

; the code knows that XFS_DIR2_DATA_FD_COUNT is 3

struct xfs_dir2_data_hdr

        magic           dd ?                    ; XFS_DIR2_DATA_MAGIC or XFS_DIR2_BLOCK_MAGIC

        bestfree        xfs_dir2_data_free

        bestfree2       xfs_dir2_data_free

        bestfree3       xfs_dir2_data_free

ends

; leaf block entry

struct xfs_dir2_leaf_entry

        hashval         dd ?            ; hash value of name

        address         dd ?            ; address of data entry

ends

; the tail of directory block

struct xfs_dir2_block_tail

        count           dd ?            ; count of leaf entries

        stale           dd ?            ; count of stale leaf entries

ends

; generic single-block structure, for xfs_db

struct xfs_dir2_block

        hdr             xfs_dir2_data_hdr

        u               xfs_dir2_data_union

;        leaf            xfs_dir2_leaf_entry

;        tail            xfs_dir2_block_tail

ends

;

struct xfs_dir2_data

        hdr             xfs_dir2_data_hdr       ; magic XFS_DIR2_DATA_MAGIC

        u               xfs_dir2_data_union

ends

;

struct xfs_da_blkinfo

        forw            dd ?            ; previous block in list

        back            dd ?            ; following block in list

        magic           dw ?            ; validity check on block

        pad             dw ?            ; unused

ends

; leaf block header

struct xfs_dir2_leaf_hdr

        info            xfs_da_blkinfo  ; header for da routines

        count           dw ?            ; count of entries

        stale           dw ?            ; count of stale entries

ends

; leaf block tail

struct xfs_dir2_leaf_tail

        bestcount       dd ?

ends

; leaf block

; bests and tail are at the end of the block for single-leaf only

; (magic = XFS_DIR2_LEAF1_MAGIC not XFS_DIR2_LEAFN_MAGIC)

struct xfs_dir2_leaf

        hdr             xfs_dir2_leaf_hdr       ; leaf header

        ents            xfs_dir2_leaf_entry     ; entries

;       bests           dw ?                    ; best free counts

;       tail            xfs_dir2_leaf_tail      ; leaf tail

ends

; header of 'free' block part

struct xfs_dir2_free_hdr

        magic           dd ?    ; XFS_DIR2_FREE_MAGIC

        firstdb         dd ?    ; db of first entry

        nvalid          dd ?    ; count of valid entries

        nused           dd ?    ; count of used entries

ends

; 'free' part of directiry block

struct xfs_dir2_free

        hdr             xfs_dir2_free_hdr       ; block header

        bests           dw ?                    ; best free counts

                                                ; unused entries are -1 (XFS_NULL)

ends

; b+tree node header

struct xfs_da_node_hdr

        info            xfs_da_blkinfo

        count           dw ?

        level           dw ?

ends

; b+tree node

struct xfs_da_node_entry

        hashval         dd ?            ; hash value for this descendant

        before          dd ?            ; Btree block before this key

ends

;

struct xfs_da_intnode

        hdr             xfs_da_node_hdr

        btree           xfs_da_node_entry

ends

; packet extent

struct xfs_bmbt_rec

        l0              dq ?

        l1              dq ?

ends

; unpacked extent

struct xfs_bmbt_irec

        br_startoff     dq ?            ; starting file offset

        br_startblock   dq ?            ; starting block number

        br_blockcount   dd ?            ; number of blocks

        br_state        dd ?            ; extent state

ends

; bmap root header, on-disk form only

struct xfs_bmdr_block

        bb_level        dw ?            ; 0 is a leaf

        bb_numrecs      dw ?            ; current number of data records

ends

; key structure for non-leaf levels of the tree

struct xfs_bmbt_key

        br_startoff     dq ?            ; starting file offset

ends

sizeof.xfs_bmbt_ptr = 8                 ; workaround

sizeof.xfs_bmdr_ptr = 8                 ; workaround

; long form header: bmap btrees

; xfs_btree_lblock is xfs_bmbt_block (xfs_btree.h)

struct xfs_bmbt_block

        bb_magic        dd ?            ; magic number for block type

        bb_level        dw ?            ; 0 is a leaf

        bb_numrecs      dw ?            ; current number of data records

        bb_leftsib      dq ?            ; left sibling block or NULLDFSBNO

        bb_rightsib     dq ?            ; right sibling block or NULLDFSBNO

ends

; high level inode structure

struct xfs_inode

        di_core                 xfs_dinode_core ; main info, aka core

        di_next_unlinked        dd ?            ; unlinked but still used inode (if any, XFS_NULL otherwise)

        di_u                    db ?            ; data fork inode part

;        di_a                    db ?           ; data attribute

ends

; internal data for every XFS partition

; this _is_ XFS partition structure

; most fields are unpacked or bswap'ed values from the superblock, so see xfs_sb structure above

struct XFS PARTITION

        Lock                    MUTEX ?         ; access mutex

        blocksize               dd ?

        sectsize                dd ?

        dirblocksize            dd ?

        rootino                 dq ?

        cur_block               dd ?

        cur_inode               dd ?

        cur_sect                dd ?

        cur_dirblock            dd ?

        tmp_inode               dd ?

        versionnum              dd ?

        features2               dd ?

        inodesize               dd ?

        inopblock               dd ?

        blocklog                dd ?

        sectlog                 dd ?

        inodelog                dd ?

        inopblog                dd ?

        agblklog                dd ?

        blockmsectlog           dd ?

        inodetoblocklog         dd ?

        dirblklog               dd ?

        sectpblock              dd ?

        agblocks                dd ?

        ; helpers, temporary vars, etc

        agblockmask             dq ?

        extent                  xfs_bmbt_irec

        left_extents            dd ?

        left_leaves             dd ?

        bytes_to_read           dd ?

        bytes_read              dd ?

        entries_read            dd ?

        file_offset             dq ?

        max_dirblockaddr        dd ?

        next_block_num          dq ?

        dir2_leaf_offset_blocks dd ?

        dir2_free_offset_blocks dd ?

        cur_inode_save          dd ?

        bytes_left_in_file      dq ?

        ro_nextents             dd ?

        bb_ptrs                 dd ?

        maxnumrecs              dd ?

        buffer_pos              dd ?

        eof                     dd ?

ends