520 lines
18 KiB
C
520 lines
18 KiB
C
/*
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* Copyright 2000-2002 by Hans Reiser, licensing governed by reiserfs/README
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*
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* GRUB -- GRand Unified Bootloader
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* Copyright (C) 2000, 2001 Free Software Foundation, Inc.
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*
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* (C) Copyright 2003 - 2004
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* Sysgo AG, <www.elinos.com>, Pavel Bartusek <pba@sysgo.com>
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*
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*
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* This program is free software; you can redistribute it and/or modify
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* it under the terms of the GNU General Public License as published by
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* the Free Software Foundation; either version 2 of the License, or
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* (at your option) any later version.
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*
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* This program is distributed in the hope that it will be useful,
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* but WITHOUT ANY WARRANTY; without even the implied warranty of
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* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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* GNU General Public License for more details.
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*
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* You should have received a copy of the GNU General Public License
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* along with this program; if not, write to the Free Software
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* Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
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*/
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/* An implementation for the ReiserFS filesystem ported from GRUB.
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* Some parts of this code (mainly the structures and defines) are
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* from the original reiser fs code, as found in the linux kernel.
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*/
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#ifndef __BYTE_ORDER
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#if defined(__LITTLE_ENDIAN) && !defined(__BIG_ENDIAN)
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#define __BYTE_ORDER __LITTLE_ENDIAN
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#elif defined(__BIG_ENDIAN) && !defined(__LITTLE_ENDIAN)
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#define __BYTE_ORDER __BIG_ENDIAN
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#else
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#error "unable to define __BYTE_ORDER"
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#endif
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#endif /* not __BYTE_ORDER */
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#define FSYS_BUFLEN 0x8000
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#define FSYS_BUF fsys_buf
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/* This is the new super block of a journaling reiserfs system */
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struct reiserfs_super_block
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{
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__u32 s_block_count; /* blocks count */
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__u32 s_free_blocks; /* free blocks count */
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__u32 s_root_block; /* root block number */
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__u32 s_journal_block; /* journal block number */
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__u32 s_journal_dev; /* journal device number */
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__u32 s_journal_size; /* size of the journal on FS creation. used to make sure they don't overflow it */
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__u32 s_journal_trans_max; /* max number of blocks in a transaction. */
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__u32 s_journal_magic; /* random value made on fs creation */
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__u32 s_journal_max_batch; /* max number of blocks to batch into a trans */
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__u32 s_journal_max_commit_age; /* in seconds, how old can an async commit be */
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__u32 s_journal_max_trans_age; /* in seconds, how old can a transaction be */
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__u16 s_blocksize; /* block size */
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__u16 s_oid_maxsize; /* max size of object id array */
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__u16 s_oid_cursize; /* current size of object id array */
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__u16 s_state; /* valid or error */
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char s_magic[16]; /* reiserfs magic string indicates that file system is reiserfs */
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__u16 s_tree_height; /* height of disk tree */
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__u16 s_bmap_nr; /* amount of bitmap blocks needed to address each block of file system */
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__u16 s_version;
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char s_unused[128]; /* zero filled by mkreiserfs */
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};
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#define sb_root_block(sbp) (__le32_to_cpu((sbp)->s_root_block))
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#define sb_journal_block(sbp) (__le32_to_cpu((sbp)->s_journal_block))
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#define set_sb_journal_block(sbp,v) ((sbp)->s_journal_block = __cpu_to_le32(v))
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#define sb_journal_size(sbp) (__le32_to_cpu((sbp)->s_journal_size))
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#define sb_blocksize(sbp) (__le16_to_cpu((sbp)->s_blocksize))
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#define set_sb_blocksize(sbp,v) ((sbp)->s_blocksize = __cpu_to_le16(v))
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#define sb_version(sbp) (__le16_to_cpu((sbp)->s_version))
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#define set_sb_version(sbp,v) ((sbp)->s_version = __cpu_to_le16(v))
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#define REISERFS_MAX_SUPPORTED_VERSION 2
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#define REISERFS_SUPER_MAGIC_STRING "ReIsErFs"
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#define REISER2FS_SUPER_MAGIC_STRING "ReIsEr2Fs"
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#define REISER3FS_SUPER_MAGIC_STRING "ReIsEr3Fs"
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#define MAX_HEIGHT 7
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/* must be correct to keep the desc and commit structs at 4k */
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#define JOURNAL_TRANS_HALF 1018
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/* first block written in a commit. */
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struct reiserfs_journal_desc {
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__u32 j_trans_id; /* id of commit */
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__u32 j_len; /* length of commit. len +1 is the commit block */
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__u32 j_mount_id; /* mount id of this trans*/
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__u32 j_realblock[JOURNAL_TRANS_HALF]; /* real locations for the first blocks */
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char j_magic[12];
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};
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/* last block written in a commit */
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struct reiserfs_journal_commit {
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__u32 j_trans_id; /* must match j_trans_id from the desc block */
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__u32 j_len; /* ditto */
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__u32 j_realblock[JOURNAL_TRANS_HALF]; /* real locations for the last blocks */
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char j_digest[16]; /* md5 sum of all the blocks involved, including desc and commit. not used, kill it */
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};
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/* this header block gets written whenever a transaction is considered
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fully flushed, and is more recent than the last fully flushed
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transaction.
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fully flushed means all the log blocks and all the real blocks are
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on disk, and this transaction does not need to be replayed.
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*/
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struct reiserfs_journal_header {
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/* id of last fully flushed transaction */
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__u32 j_last_flush_trans_id;
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/* offset in the log of where to start replay after a crash */
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__u32 j_first_unflushed_offset;
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/* mount id to detect very old transactions */
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__u32 j_mount_id;
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};
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/* magic string to find desc blocks in the journal */
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#define JOURNAL_DESC_MAGIC "ReIsErLB"
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/*
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* directories use this key as well as old files
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*/
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struct offset_v1
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{
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/*
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* for regular files this is the offset to the first byte of the
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* body, contained in the object-item, as measured from the start of
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* the entire body of the object.
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*
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* for directory entries, k_offset consists of hash derived from
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* hashing the name and using few bits (23 or more) of the resulting
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* hash, and generation number that allows distinguishing names with
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* hash collisions. If number of collisions overflows generation
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* number, we return EEXIST. High order bit is 0 always
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*/
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__u32 k_offset;
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__u32 k_uniqueness;
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};
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struct offset_v2 {
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/*
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* for regular files this is the offset to the first byte of the
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* body, contained in the object-item, as measured from the start of
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* the entire body of the object.
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*
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* for directory entries, k_offset consists of hash derived from
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* hashing the name and using few bits (23 or more) of the resulting
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* hash, and generation number that allows distinguishing names with
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* hash collisions. If number of collisions overflows generation
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* number, we return EEXIST. High order bit is 0 always
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*/
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#if defined(__LITTLE_ENDIAN_BITFIELD)
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/* little endian version */
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__u64 k_offset:60;
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__u64 k_type: 4;
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#elif defined(__BIG_ENDIAN_BITFIELD)
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/* big endian version */
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__u64 k_type: 4;
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__u64 k_offset:60;
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#else
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#error "__LITTLE_ENDIAN_BITFIELD or __BIG_ENDIAN_BITFIELD must be defined"
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#endif
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} __attribute__ ((__packed__));
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#define TYPE_MAXTYPE 3
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#define TYPE_ANY 15
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#if (__BYTE_ORDER == __BIG_ENDIAN)
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typedef union {
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struct offset_v2 offset_v2;
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__u64 linear;
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} __attribute__ ((__packed__)) offset_v2_esafe_overlay;
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static inline __u16 offset_v2_k_type( const struct offset_v2 *v2 )
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{
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offset_v2_esafe_overlay tmp = *(const offset_v2_esafe_overlay *)v2;
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tmp.linear = __le64_to_cpu( tmp.linear );
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return (tmp.offset_v2.k_type <= TYPE_MAXTYPE)?tmp.offset_v2.k_type:TYPE_ANY;
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}
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static inline loff_t offset_v2_k_offset( const struct offset_v2 *v2 )
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{
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offset_v2_esafe_overlay tmp = *(const offset_v2_esafe_overlay *)v2;
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tmp.linear = __le64_to_cpu( tmp.linear );
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return tmp.offset_v2.k_offset;
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}
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#elif (__BYTE_ORDER == __LITTLE_ENDIAN)
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# define offset_v2_k_type(v2) ((v2)->k_type)
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# define offset_v2_k_offset(v2) ((v2)->k_offset)
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#else
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#error "__BYTE_ORDER must be __LITTLE_ENDIAN or __BIG_ENDIAN"
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#endif
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struct key
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{
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/* packing locality: by default parent directory object id */
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__u32 k_dir_id;
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/* object identifier */
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__u32 k_objectid;
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/* the offset and node type (old and new form) */
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union
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{
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struct offset_v1 v1;
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struct offset_v2 v2;
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}
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u;
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};
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#define KEY_SIZE (sizeof (struct key))
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/* Header of a disk block. More precisely, header of a formatted leaf
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or internal node, and not the header of an unformatted node. */
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struct block_head
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{
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__u16 blk_level; /* Level of a block in the tree. */
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__u16 blk_nr_item; /* Number of keys/items in a block. */
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__u16 blk_free_space; /* Block free space in bytes. */
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struct key blk_right_delim_key; /* Right delimiting key for this block (supported for leaf level nodes
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only) */
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};
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#define BLKH_SIZE (sizeof (struct block_head))
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#define DISK_LEAF_NODE_LEVEL 1 /* Leaf node level. */
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struct item_head
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{
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/* Everything in the tree is found by searching for it based on
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* its key.*/
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struct key ih_key;
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union {
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/* The free space in the last unformatted node of an
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indirect item if this is an indirect item. This
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equals 0xFFFF iff this is a direct item or stat data
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item. Note that the key, not this field, is used to
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determine the item type, and thus which field this
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union contains. */
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__u16 ih_free_space;
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/* Iff this is a directory item, this field equals the
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number of directory entries in the directory item. */
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__u16 ih_entry_count;
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} __attribute__ ((__packed__)) u;
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__u16 ih_item_len; /* total size of the item body */
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__u16 ih_item_location; /* an offset to the item body
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* within the block */
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__u16 ih_version; /* 0 for all old items, 2 for new
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ones. Highest bit is set by fsck
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temporary, cleaned after all
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done */
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} __attribute__ ((__packed__));
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/* size of item header */
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#define IH_SIZE (sizeof (struct item_head))
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#define ITEM_VERSION_1 0
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#define ITEM_VERSION_2 1
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#define ih_version(ih) (__le16_to_cpu((ih)->ih_version))
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#define IH_KEY_OFFSET(ih) (ih_version(ih) == ITEM_VERSION_1 \
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? __le32_to_cpu((ih)->ih_key.u.v1.k_offset) \
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: offset_v2_k_offset(&((ih)->ih_key.u.v2)))
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#define IH_KEY_ISTYPE(ih, type) (ih_version(ih) == ITEM_VERSION_1 \
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? __le32_to_cpu((ih)->ih_key.u.v1.k_uniqueness) == V1_##type \
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: offset_v2_k_type(&((ih)->ih_key.u.v2)) == V2_##type)
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/***************************************************************************/
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/* DISK CHILD */
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/***************************************************************************/
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/* Disk child pointer: The pointer from an internal node of the tree
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to a node that is on disk. */
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struct disk_child {
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__u32 dc_block_number; /* Disk child's block number. */
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__u16 dc_size; /* Disk child's used space. */
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__u16 dc_reserved;
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};
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#define DC_SIZE (sizeof(struct disk_child))
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#define dc_block_number(dc_p) (__le32_to_cpu((dc_p)->dc_block_number))
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/*
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* old stat data is 32 bytes long. We are going to distinguish new one by
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* different size
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*/
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struct stat_data_v1
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{
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__u16 sd_mode; /* file type, permissions */
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__u16 sd_nlink; /* number of hard links */
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__u16 sd_uid; /* owner */
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__u16 sd_gid; /* group */
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__u32 sd_size; /* file size */
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__u32 sd_atime; /* time of last access */
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__u32 sd_mtime; /* time file was last modified */
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__u32 sd_ctime; /* time inode (stat data) was last changed (except changes to sd_atime and sd_mtime) */
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union {
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__u32 sd_rdev;
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__u32 sd_blocks; /* number of blocks file uses */
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} __attribute__ ((__packed__)) u;
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__u32 sd_first_direct_byte; /* first byte of file which is stored
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in a direct item: except that if it
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equals 1 it is a symlink and if it
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equals ~(__u32)0 there is no
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direct item. The existence of this
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field really grates on me. Let's
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replace it with a macro based on
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sd_size and our tail suppression
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policy. Someday. -Hans */
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} __attribute__ ((__packed__));
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#define stat_data_v1(ih) (ih_version(ih) == ITEM_VERSION_1)
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#define sd_v1_mode(sdp) ((sdp)->sd_mode)
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#define sd_v1_nlink(sdp) (__le16_to_cpu((sdp)->sd_nlink))
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#define sd_v1_uid(sdp) (__le16_to_cpu((sdp)->sd_uid))
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#define sd_v1_gid(sdp) (__le16_to_cpu((sdp)->sd_gid))
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#define sd_v1_size(sdp) (__le32_to_cpu((sdp)->sd_size))
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#define sd_v1_mtime(sdp) (__le32_to_cpu((sdp)->sd_mtime))
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/* Stat Data on disk (reiserfs version of UFS disk inode minus the
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address blocks) */
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struct stat_data {
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__u16 sd_mode; /* file type, permissions */
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__u16 sd_attrs; /* persistent inode flags */
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__u32 sd_nlink; /* number of hard links */
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__u64 sd_size; /* file size */
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__u32 sd_uid; /* owner */
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__u32 sd_gid; /* group */
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__u32 sd_atime; /* time of last access */
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__u32 sd_mtime; /* time file was last modified */
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__u32 sd_ctime; /* time inode (stat data) was last changed (except changes to sd_atime and sd_mtime) */
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__u32 sd_blocks;
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union {
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__u32 sd_rdev;
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__u32 sd_generation;
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/*__u32 sd_first_direct_byte; */
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/* first byte of file which is stored in a
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direct item: except that if it equals 1
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it is a symlink and if it equals
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~(__u32)0 there is no direct item. The
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existence of this field really grates
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on me. Let's replace it with a macro
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based on sd_size and our tail
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suppression policy? */
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} __attribute__ ((__packed__)) u;
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} __attribute__ ((__packed__));
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#define stat_data_v2(ih) (ih_version(ih) == ITEM_VERSION_2)
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#define sd_v2_mode(sdp) (__le16_to_cpu((sdp)->sd_mode))
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#define sd_v2_nlink(sdp) (__le32_to_cpu((sdp)->sd_nlink))
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#define sd_v2_size(sdp) (__le64_to_cpu((sdp)->sd_size))
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#define sd_v2_uid(sdp) (__le32_to_cpu((sdp)->sd_uid))
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#define sd_v2_gid(sdp) (__le32_to_cpu((sdp)->sd_gid))
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#define sd_v2_mtime(sdp) (__le32_to_cpu((sdp)->sd_mtime))
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#define sd_mode(sdp) (__le16_to_cpu((sdp)->sd_mode))
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#define sd_size(sdp) (__le32_to_cpu((sdp)->sd_size))
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#define sd_size_hi(sdp) (__le32_to_cpu((sdp)->sd_size_hi))
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struct reiserfs_de_head
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{
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__u32 deh_offset; /* third component of the directory entry key */
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__u32 deh_dir_id; /* objectid of the parent directory of the
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object, that is referenced by directory entry */
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__u32 deh_objectid;/* objectid of the object, that is referenced by
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directory entry */
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__u16 deh_location;/* offset of name in the whole item */
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__u16 deh_state; /* whether 1) entry contains stat data (for
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future), and 2) whether entry is hidden
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(unlinked) */
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};
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#define DEH_SIZE (sizeof (struct reiserfs_de_head))
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#define deh_offset(p_deh) (__le32_to_cpu((p_deh)->deh_offset))
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#define deh_dir_id(p_deh) (__le32_to_cpu((p_deh)->deh_dir_id))
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#define deh_objectid(p_deh) (__le32_to_cpu((p_deh)->deh_objectid))
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#define deh_location(p_deh) (__le16_to_cpu((p_deh)->deh_location))
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#define deh_state(p_deh) (__le16_to_cpu((p_deh)->deh_state))
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#define DEH_Statdata (1 << 0) /* not used now */
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#define DEH_Visible (1 << 2)
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#define SD_OFFSET 0
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#define SD_UNIQUENESS 0
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#define DOT_OFFSET 1
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#define DOT_DOT_OFFSET 2
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#define DIRENTRY_UNIQUENESS 500
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#define V1_TYPE_STAT_DATA 0x0
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#define V1_TYPE_DIRECT 0xffffffff
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#define V1_TYPE_INDIRECT 0xfffffffe
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#define V1_TYPE_DIRECTORY_MAX 0xfffffffd
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#define V2_TYPE_STAT_DATA 0
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#define V2_TYPE_INDIRECT 1
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#define V2_TYPE_DIRECT 2
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#define V2_TYPE_DIRENTRY 3
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#define REISERFS_ROOT_OBJECTID 2
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#define REISERFS_ROOT_PARENT_OBJECTID 1
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#define REISERFS_DISK_OFFSET_IN_BYTES (64 * 1024)
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/* the spot for the super in versions 3.5 - 3.5.11 (inclusive) */
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#define REISERFS_OLD_DISK_OFFSET_IN_BYTES (8 * 1024)
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#define REISERFS_OLD_BLOCKSIZE 4096
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#define S_ISREG(mode) (((mode) & 0170000) == 0100000)
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#define S_ISDIR(mode) (((mode) & 0170000) == 0040000)
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#define S_ISLNK(mode) (((mode) & 0170000) == 0120000)
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#define PATH_MAX 1024 /* include/linux/limits.h */
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#define MAX_LINK_COUNT 5 /* number of symbolic links to follow */
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/* The size of the node cache */
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#define FSYSREISER_CACHE_SIZE 24*1024
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#define FSYSREISER_MIN_BLOCKSIZE SECTOR_SIZE
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#define FSYSREISER_MAX_BLOCKSIZE FSYSREISER_CACHE_SIZE / 3
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/* Info about currently opened file */
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struct fsys_reiser_fileinfo
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{
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__u32 k_dir_id;
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__u32 k_objectid;
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};
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/* In memory info about the currently mounted filesystem */
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struct fsys_reiser_info
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{
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/* The last read item head */
|
|
struct item_head *current_ih;
|
|
/* The last read item */
|
|
char *current_item;
|
|
/* The information for the currently opened file */
|
|
struct fsys_reiser_fileinfo fileinfo;
|
|
/* The start of the journal */
|
|
__u32 journal_block;
|
|
/* The size of the journal */
|
|
__u32 journal_block_count;
|
|
/* The first valid descriptor block in journal
|
|
(relative to journal_block) */
|
|
__u32 journal_first_desc;
|
|
|
|
/* The ReiserFS version. */
|
|
__u16 version;
|
|
/* The current depth of the reiser tree. */
|
|
__u16 tree_depth;
|
|
/* SECTOR_SIZE << blocksize_shift == blocksize. */
|
|
__u8 blocksize_shift;
|
|
/* 1 << full_blocksize_shift == blocksize. */
|
|
__u8 fullblocksize_shift;
|
|
/* The reiserfs block size (must be a power of 2) */
|
|
__u16 blocksize;
|
|
/* The number of cached tree nodes */
|
|
__u16 cached_slots;
|
|
/* The number of valid transactions in journal */
|
|
__u16 journal_transactions;
|
|
|
|
unsigned int blocks[MAX_HEIGHT];
|
|
unsigned int next_key_nr[MAX_HEIGHT];
|
|
};
|
|
|
|
/* The cached s+tree blocks in FSYS_BUF, see below
|
|
* for a more detailed description.
|
|
*/
|
|
#define ROOT ((char *) ((int) FSYS_BUF))
|
|
#define CACHE(i) (ROOT + ((i) << INFO->fullblocksize_shift))
|
|
#define LEAF CACHE (DISK_LEAF_NODE_LEVEL)
|
|
|
|
#define BLOCKHEAD(cache) ((struct block_head *) cache)
|
|
#define ITEMHEAD ((struct item_head *) ((int) LEAF + BLKH_SIZE))
|
|
#define KEY(cache) ((struct key *) ((int) cache + BLKH_SIZE))
|
|
#define DC(cache) ((struct disk_child *) \
|
|
((int) cache + BLKH_SIZE + KEY_SIZE * nr_item))
|
|
/* The fsys_reiser_info block.
|
|
*/
|
|
#define INFO \
|
|
((struct fsys_reiser_info *) ((int) FSYS_BUF + FSYSREISER_CACHE_SIZE))
|
|
/*
|
|
* The journal cache. For each transaction it contains the number of
|
|
* blocks followed by the real block numbers of this transaction.
|
|
*
|
|
* If the block numbers of some transaction won't fit in this space,
|
|
* this list is stopped with a 0xffffffff marker and the remaining
|
|
* uncommitted transactions aren't cached.
|
|
*/
|
|
#define JOURNAL_START ((__u32 *) (INFO + 1))
|
|
#define JOURNAL_END ((__u32 *) (FSYS_BUF + FSYS_BUFLEN))
|
|
|
|
|
|
static __inline__ unsigned long
|
|
log2 (unsigned long word)
|
|
{
|
|
#ifdef __I386__
|
|
__asm__ ("bsfl %1,%0"
|
|
: "=r" (word)
|
|
: "r" (word));
|
|
return word;
|
|
#else
|
|
int i;
|
|
|
|
for(i=0; i<(8*sizeof(word)); i++)
|
|
if ((1<<i) & word)
|
|
return i;
|
|
|
|
return 0;
|
|
#endif
|
|
}
|
|
|
|
static __inline__ int
|
|
is_power_of_two (unsigned long word)
|
|
{
|
|
return (word & -word) == word;
|
|
}
|
|
|
|
extern const char *bb_mode_string(int mode);
|
|
extern int reiserfs_devread (int sector, int byte_offset, int byte_len, char *buf);
|