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/* jfs.h - an extractions from linux/include/linux/jfs/jfs* into one file */
/*
* GRUB -- GRand Unified Bootloader
* Copyright (C) 2000 International Business Machines Corp.
* Copyright (C) 2001 Free Software Foundation, Inc.
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See
* the GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston,
* MA 02110-1301, USA.
*/
#ifndef _JFS_H_
#define _JFS_H_
/* those are from jfs_filsys.h */
/*
* file system option (superblock flag)
*/
/* platform option (conditional compilation) */
#define JFS_AIX 0x80000000 /* AIX support */
/* POSIX name/directory support */
#define JFS_OS2 0x40000000 /* OS/2 support */
/* case-insensitive name/directory support */
#define JFS_LINUX 0x10000000 /* Linux support */
/* case-sensitive name/directory support */
/* directory option */
#define JFS_UNICODE 0x00000001 /* unicode name */
/* bba */
#define JFS_SWAP_BYTES 0x00100000 /* running on big endian computer */
/*
* buffer cache configuration
*/
/* page size */
#ifdef PSIZE
#undef PSIZE
#endif
#define PSIZE 4096 /* page size (in byte) */
/*
* fs fundamental size
*
* PSIZE >= file system block size >= PBSIZE >= DISIZE
*/
#define PBSIZE 512 /* physical block size (in byte) */
#define DISIZE 512 /* on-disk inode size (in byte) */
#define L2DISIZE 9
#define INOSPERIAG 4096 /* number of disk inodes per iag */
#define L2INOSPERIAG 12
#define INOSPEREXT 32 /* number of disk inode per extent */
#define L2INOSPEREXT 5
/* Minimum number of bytes supported for a JFS partition */
#define MINJFS (0x1000000)
/*
* fixed byte offset address
*/
#define SUPER1_OFF 0x8000 /* primary superblock */
#define AITBL_OFF (SUPER1_OFF + PSIZE + (PSIZE << 1))
/*
* fixed reserved inode number
*/
/* aggregate inode */
#define AGGREGATE_I 1 /* aggregate inode map inode */
#define FILESYSTEM_I 16 /* 1st/only fileset inode in ait:
* fileset inode map inode
*/
/* per fileset inode */
#define ROOT_I 2 /* fileset root inode */
/*
* directory configuration
*/
#define JFS_NAME_MAX 255
#define JFS_PATH_MAX PSIZE
#if 0
typedef unsigned char u8;
typedef char s8;
typedef unsigned short u16;
typedef short s16;
typedef unsigned int u32;
typedef int s32;
typedef unsigned long long u64;
typedef long long s64;
#endif
typedef u16 UniChar;
/* these from jfs_btree.h */
/* btpaget_t flag */
#define BT_TYPE 0x07 /* B+-tree index */
#define BT_ROOT 0x01 /* root page */
#define BT_LEAF 0x02 /* leaf page */
#define BT_INTERNAL 0x04 /* internal page */
#define BT_RIGHTMOST 0x10 /* rightmost page */
#define BT_LEFTMOST 0x20 /* leftmost page */
/* those are from jfs_types.h */
struct timestruc_t {
u32 tv_sec;
u32 tv_nsec;
};
/*
* physical xd (pxd)
*/
typedef struct {
unsigned len:24;
unsigned addr1:8;
u32 addr2;
} pxd_t;
/* xd_t field extraction */
#define lengthPXD(pxd) ((pxd)->len)
#define addressPXD(pxd) (((s64)((pxd)->addr1)) << 32 | ((pxd)->addr2))
/*
* data extent descriptor (dxd)
*/
typedef struct {
unsigned flag:8; /* 1: flags */
unsigned rsrvd:24; /* 3: */
u32 size; /* 4: size in byte */
unsigned len:24; /* 3: length in unit of fsblksize */
unsigned addr1:8; /* 1: address in unit of fsblksize */
u32 addr2; /* 4: address in unit of fsblksize */
} dxd_t; /* - 16 - */
/*
* DASD limit information - stored in directory inode
*/
typedef struct dasd {
u8 thresh; /* Alert Threshold (in percent) */
u8 delta; /* Alert Threshold delta (in percent) */
u8 rsrvd1;
u8 limit_hi; /* DASD limit (in logical blocks) */
u32 limit_lo; /* DASD limit (in logical blocks) */
u8 rsrvd2[3];
u8 used_hi; /* DASD usage (in logical blocks) */
u32 used_lo; /* DASD usage (in logical blocks) */
} dasd_t;
/* from jfs_superblock.h */
#define JFS_MAGIC 0x3153464A /* "JFS1" */
struct jfs_superblock
{
u32 s_magic; /* 4: magic number */
u32 s_version; /* 4: version number */
s64 s_size; /* 8: aggregate size in hardware/LVM blocks;
* VFS: number of blocks
*/
s32 s_bsize; /* 4: aggregate block size in bytes;
* VFS: fragment size
*/
s16 s_l2bsize; /* 2: log2 of s_bsize */
s16 s_l2bfactor; /* 2: log2(s_bsize/hardware block size) */
s32 s_pbsize; /* 4: hardware/LVM block size in bytes */
s16 s_l2pbsize; /* 2: log2 of s_pbsize */
s16 pad; /* 2: padding necessary for alignment */
u32 s_agsize; /* 4: allocation group size in aggr. blocks */
u32 s_flag; /* 4: aggregate attributes:
* see jfs_filsys.h
*/
u32 s_state; /* 4: mount/unmount/recovery state:
* see jfs_filsys.h
*/
s32 s_compress; /* 4: > 0 if data compression */
pxd_t s_ait2; /* 8: first extent of secondary
* aggregate inode table
*/
pxd_t s_aim2; /* 8: first extent of secondary
* aggregate inode map
*/
u32 s_logdev; /* 4: device address of log */
s32 s_logserial; /* 4: log serial number at aggregate mount */
pxd_t s_logpxd; /* 8: inline log extent */
pxd_t s_fsckpxd; /* 8: inline fsck work space extent */
struct timestruc_t s_time; /* 8: time last updated */
s32 s_fsckloglen; /* 4: Number of filesystem blocks reserved for
* the fsck service log.
* N.B. These blocks are divided among the
* versions kept. This is not a per
* version size.
* N.B. These blocks are included in the
* length field of s_fsckpxd.
*/
s8 s_fscklog; /* 1: which fsck service log is most recent
* 0 => no service log data yet
* 1 => the first one
* 2 => the 2nd one
*/
char s_fpack[11]; /* 11: file system volume name
* N.B. This must be 11 bytes to
* conform with the OS/2 BootSector
* requirements
*/
/* extendfs() parameter under s_state & FM_EXTENDFS */
s64 s_xsize; /* 8: extendfs s_size */
pxd_t s_xfsckpxd; /* 8: extendfs fsckpxd */
pxd_t s_xlogpxd; /* 8: extendfs logpxd */
/* - 128 byte boundary - */
/*
* DFS VFS support (preliminary)
*/
char s_attach; /* 1: VFS: flag: set when aggregate is attached
*/
u8 rsrvd4[7]; /* 7: reserved - set to 0 */
u64 totalUsable; /* 8: VFS: total of 1K blocks which are
* available to "normal" (non-root) users.
*/
u64 minFree; /* 8: VFS: # of 1K blocks held in reserve for
* exclusive use of root. This value can be 0,
* and if it is then totalUsable will be equal
* to # of blocks in aggregate. I believe this
* means that minFree + totalUsable = # blocks.
* In that case, we don't need to store both
* totalUsable and minFree since we can compute
* one from the other. I would guess minFree
* would be the one we should store, and
* totalUsable would be the one we should
* compute. (Just a guess...)
*/
u64 realFree; /* 8: VFS: # of free 1K blocks can be used by
* "normal" users. It may be this is something
* we should compute when asked for instead of
* storing in the superblock. I don't know how
* often this information is needed.
*/
/*
* graffiti area
*/
};
/* from jfs_dtree.h */
/*
* entry segment/slot
*
* an entry consists of type dependent head/only segment/slot and
* additional segments/slots linked vi next field;
* N.B. last/only segment of entry is terminated by next = -1;
*/
/*
* directory page slot
*/
typedef struct {
s8 next; /* 1: */
s8 cnt; /* 1: */
UniChar name[15]; /* 30: */
} dtslot_t; /* (32) */
#define DTSLOTDATALEN 15
/*
* internal node entry head/only segment
*/
typedef struct {
pxd_t xd; /* 8: child extent descriptor */
s8 next; /* 1: */
u8 namlen; /* 1: */
UniChar name[11]; /* 22: 2-byte aligned */
} idtentry_t; /* (32) */
/*
* leaf node entry head/only segment
*
* For legacy filesystems, name contains 13 unichars -- no index field
*/
typedef struct {
u32 inumber; /* 4: 4-byte aligned */
s8 next; /* 1: */
u8 namlen; /* 1: */
UniChar name[11]; /* 22: 2-byte aligned */
u32 index; /* 4: index into dir_table */
} ldtentry_t; /* (32) */
#define DTLHDRDATALEN 11
/*
* dir_table used for directory traversal during readdir
*/
/*
* Maximum entry in inline directory table
*/
typedef struct dir_table_slot {
u8 rsrvd; /* 1: */
u8 flag; /* 1: 0 if free */
u8 slot; /* 1: slot within leaf page of entry */
u8 addr1; /* 1: upper 8 bits of leaf page address */
u32 addr2; /* 4: lower 32 bits of leaf page address -OR-
index of next entry when this entry was deleted */
} dir_table_slot_t; /* (8) */
/*
* directory root page (in-line in on-disk inode):
*
* cf. dtpage_t below.
*/
typedef union {
struct {
dasd_t DASD; /* 16: DASD limit/usage info F226941 */
u8 flag; /* 1: */
s8 nextindex; /* 1: next free entry in stbl */
s8 freecnt; /* 1: free count */
s8 freelist; /* 1: freelist header */
u32 idotdot; /* 4: parent inode number */
s8 stbl[8]; /* 8: sorted entry index table */
} header; /* (32) */
dtslot_t slot[9];
} dtroot_t;
/*
* directory regular page:
*
* entry slot array of 32 byte slot
*
* sorted entry slot index table (stbl):
* contiguous slots at slot specified by stblindex,
* 1-byte per entry
* 512 byte block: 16 entry tbl (1 slot)
* 1024 byte block: 32 entry tbl (1 slot)
* 2048 byte block: 64 entry tbl (2 slot)
* 4096 byte block: 128 entry tbl (4 slot)
*
* data area:
* 512 byte block: 16 - 2 = 14 slot
* 1024 byte block: 32 - 2 = 30 slot
* 2048 byte block: 64 - 3 = 61 slot
* 4096 byte block: 128 - 5 = 123 slot
*
* N.B. index is 0-based; index fields refer to slot index
* except nextindex which refers to entry index in stbl;
* end of entry stot list or freelist is marked with -1.
*/
typedef union {
struct {
s64 next; /* 8: next sibling */
s64 prev; /* 8: previous sibling */
u8 flag; /* 1: */
s8 nextindex; /* 1: next entry index in stbl */
s8 freecnt; /* 1: */
s8 freelist; /* 1: slot index of head of freelist */
u8 maxslot; /* 1: number of slots in page slot[] */
s8 stblindex; /* 1: slot index of start of stbl */
u8 rsrvd[2]; /* 2: */
pxd_t self; /* 8: self pxd */
} header; /* (32) */
dtslot_t slot[128];
} dtpage_t;
/* from jfs_xtree.h */
/*
* extent allocation descriptor (xad)
*/
typedef struct xad {
unsigned flag:8; /* 1: flag */
unsigned rsvrd:16; /* 2: reserved */
unsigned off1:8; /* 1: offset in unit of fsblksize */
u32 off2; /* 4: offset in unit of fsblksize */
unsigned len:24; /* 3: length in unit of fsblksize */
unsigned addr1:8; /* 1: address in unit of fsblksize */
u32 addr2; /* 4: address in unit of fsblksize */
} xad_t; /* (16) */
/* xad_t field extraction */
#define offsetXAD(xad) (((s64)((xad)->off1)) << 32 | ((xad)->off2))
#define addressXAD(xad) (((s64)((xad)->addr1)) << 32 | ((xad)->addr2))
#define lengthXAD(xad) ((xad)->len)
/* possible values for maxentry */
#define XTPAGEMAXSLOT 256
#define XTENTRYSTART 2
/*
* xtree page:
*/
typedef union {
struct xtheader {
s64 next; /* 8: */
s64 prev; /* 8: */
u8 flag; /* 1: */
u8 rsrvd1; /* 1: */
s16 nextindex; /* 2: next index = number of entries */
s16 maxentry; /* 2: max number of entries */
s16 rsrvd2; /* 2: */
pxd_t self; /* 8: self */
} header; /* (32) */
xad_t xad[XTPAGEMAXSLOT]; /* 16 * maxentry: xad array */
} xtpage_t;
/* from jfs_dinode.h */
struct dinode {
/*
* I. base area (128 bytes)
* ------------------------
*
* define generic/POSIX attributes
*/
u32 di_inostamp; /* 4: stamp to show inode belongs to fileset */
s32 di_fileset; /* 4: fileset number */
u32 di_number; /* 4: inode number, aka file serial number */
u32 di_gen; /* 4: inode generation number */
pxd_t di_ixpxd; /* 8: inode extent descriptor */
s64 di_size; /* 8: size */
s64 di_nblocks; /* 8: number of blocks allocated */
u32 di_nlink; /* 4: number of links to the object */
u32 di_uid; /* 4: user id of owner */
u32 di_gid; /* 4: group id of owner */
u32 di_mode; /* 4: attribute, format and permission */
struct timestruc_t di_atime; /* 8: time last data accessed */
struct timestruc_t di_ctime; /* 8: time last status changed */
struct timestruc_t di_mtime; /* 8: time last data modified */
struct timestruc_t di_otime; /* 8: time created */
dxd_t di_acl; /* 16: acl descriptor */
dxd_t di_ea; /* 16: ea descriptor */
s32 di_next_index; /* 4: Next available dir_table index */
s32 di_acltype; /* 4: Type of ACL */
/*
* Extension Areas.
*
* Historically, the inode was partitioned into 4 128-byte areas,
* the last 3 being defined as unions which could have multiple
* uses. The first 96 bytes had been completely unused until
* an index table was added to the directory. It is now more
* useful to describe the last 3/4 of the inode as a single
* union. We would probably be better off redesigning the
* entire structure from scratch, but we don't want to break
* commonality with OS/2's JFS at this time.
*/
union {
struct {
/*
* This table contains the information needed to
* find a directory entry from a 32-bit index.
* If the index is small enough, the table is inline,
* otherwise, an x-tree root overlays this table
*/
dir_table_slot_t _table[12]; /* 96: inline */
dtroot_t _dtroot; /* 288: dtree root */
} _dir; /* (384) */
#define di_dirtable u._dir._table
#define di_dtroot u._dir._dtroot
#define di_parent di_dtroot.header.idotdot
#define di_DASD di_dtroot.header.DASD
struct {
union {
u8 _data[96]; /* 96: unused */
struct {
void *_imap; /* 4: unused */
u32 _gengen; /* 4: generator */
} _imap;
} _u1; /* 96: */
#define di_gengen u._file._u1._imap._gengen
union {
xtpage_t _xtroot;
struct {
u8 unused[16]; /* 16: */
dxd_t _dxd; /* 16: */
union {
u32 _rdev; /* 4: */
u8 _fastsymlink[128];
} _u;
u8 _inlineea[128];
} _special;
} _u2;
} _file;
#define di_xtroot u._file._u2._xtroot
#define di_dxd u._file._u2._special._dxd
#define di_btroot di_xtroot
#define di_inlinedata u._file._u2._special._u
#define di_rdev u._file._u2._special._u._rdev
#define di_fastsymlink u._file._u2._special._u._fastsymlink
#define di_inlineea u._file._u2._special._inlineea
} u;
};
typedef struct dinode dinode_t;
/* di_mode */
#define IFMT 0xF000 /* S_IFMT - mask of file type */
#define IFDIR 0x4000 /* S_IFDIR - directory */
#define IFREG 0x8000 /* S_IFREG - regular file */
#define IFLNK 0xA000 /* S_IFLNK - symbolic link */
/* extended mode bits (on-disk inode di_mode) */
#define INLINEEA 0x00040000 /* inline EA area free */
/* from jfs_imap.h */
#define EXTSPERIAG 128 /* number of disk inode extent per iag */
#define SMAPSZ 4 /* number of words per summary map */
#define MAXAG 128 /* maximum number of allocation groups */
/*
* inode allocation map:
*
* inode allocation map consists of
* . the inode map control page and
* . inode allocation group pages (per 4096 inodes)
* which are addressed by standard JFS xtree.
*/
/*
* inode allocation group page (per 4096 inodes of an AG)
*/
typedef struct {
s64 agstart; /* 8: starting block of ag */
s32 iagnum; /* 4: inode allocation group number */
s32 inofreefwd; /* 4: ag inode free list forward */
s32 inofreeback; /* 4: ag inode free list back */
s32 extfreefwd; /* 4: ag inode extent free list forward */
s32 extfreeback; /* 4: ag inode extent free list back */
s32 iagfree; /* 4: iag free list */
/* summary map: 1 bit per inode extent */
s32 inosmap[SMAPSZ]; /* 16: sum map of mapwords w/ free inodes;
* note: this indicates free and backed
* inodes, if the extent is not backed the
* value will be 1. if the extent is
* backed but all inodes are being used the
* value will be 1. if the extent is
* backed but at least one of the inodes is
* free the value will be 0.
*/
s32 extsmap[SMAPSZ]; /* 16: sum map of mapwords w/ free extents */
s32 nfreeinos; /* 4: number of free inodes */
s32 nfreeexts; /* 4: number of free extents */
/* (72) */
u8 pad[1976]; /* 1976: pad to 2048 bytes */
/* allocation bit map: 1 bit per inode (0 - free, 1 - allocated) */
u32 wmap[EXTSPERIAG]; /* 512: working allocation map */
u32 pmap[EXTSPERIAG]; /* 512: persistent allocation map */
pxd_t inoext[EXTSPERIAG]; /* 1024: inode extent addresses */
} iag_t; /* (4096) */
#endif /* _JFS_H_ */
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