f7d4b4d3d1
The superblock in ext2fs defines all the fields as unsigned but for some reason the in-memory superblock was carrying e2fs_bpg and e2fs_isize as signed. We should preserve the specified types for consistency. MFC after: 5 days
331 lines
12 KiB
C
331 lines
12 KiB
C
/*-
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* modified for EXT2FS support in Lites 1.1
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*
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* Aug 1995, Godmar Back (gback@cs.utah.edu)
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* University of Utah, Department of Computer Science
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*
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* $FreeBSD$
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*/
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/*-
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* Copyright (c) 2009 Aditya Sarawgi
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* All rights reserved.
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*
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* Redistribution and use in source and binary forms, with or without
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* modification, are permitted provided that the following conditions
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* are met:
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* 1. Redistributions of source code must retain the above copyright
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* notice, this list of conditions and the following disclaimer.
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* 2. Redistributions in binary form must reproduce the above copyright
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* notice, this list of conditions and the following disclaimer in the
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* documentation and/or other materials provided with the distribution.
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*
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* THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
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* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
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* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
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* ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
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* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
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* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
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* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
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* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
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* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
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* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
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* SUCH DAMAGE.
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*
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*
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*/
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#ifndef _FS_EXT2FS_EXT2FS_H_
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#define _FS_EXT2FS_EXT2FS_H_
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#include <sys/types.h>
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/*
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* Maximal count of links to a file
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*/
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#define EXT2_LINK_MAX 32000
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/*
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* A summary of contiguous blocks of various sizes is maintained
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* in each cylinder group. Normally this is set by the initial
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* value of fs_maxcontig.
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*
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* XXX:FS_MAXCONTIG is set to 16 to conserve space. Here we set
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* EXT2_MAXCONTIG to 32 for better performance.
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*/
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#define EXT2_MAXCONTIG 32
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/*
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* Constants relative to the data blocks
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*/
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#define EXT2_NDIR_BLOCKS 12
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#define EXT2_IND_BLOCK EXT2_NDIR_BLOCKS
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#define EXT2_DIND_BLOCK (EXT2_IND_BLOCK + 1)
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#define EXT2_TIND_BLOCK (EXT2_DIND_BLOCK + 1)
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#define EXT2_N_BLOCKS (EXT2_TIND_BLOCK + 1)
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#define EXT2_MAXSYMLINKLEN (EXT2_N_BLOCKS * sizeof(uint32_t))
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/*
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* The path name on which the file system is mounted is maintained
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* in fs_fsmnt. MAXMNTLEN defines the amount of space allocated in
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* the super block for this name.
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*/
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#define MAXMNTLEN 512
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/*
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* Super block for an ext2fs file system.
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*/
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struct ext2fs {
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uint32_t e2fs_icount; /* Inode count */
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uint32_t e2fs_bcount; /* blocks count */
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uint32_t e2fs_rbcount; /* reserved blocks count */
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uint32_t e2fs_fbcount; /* free blocks count */
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uint32_t e2fs_ficount; /* free inodes count */
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uint32_t e2fs_first_dblock; /* first data block */
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uint32_t e2fs_log_bsize; /* block size = 1024*(2^e2fs_log_bsize) */
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uint32_t e2fs_log_fsize; /* fragment size */
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uint32_t e2fs_bpg; /* blocks per group */
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uint32_t e2fs_fpg; /* frags per group */
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uint32_t e2fs_ipg; /* inodes per group */
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uint32_t e2fs_mtime; /* mount time */
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uint32_t e2fs_wtime; /* write time */
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uint16_t e2fs_mnt_count; /* mount count */
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uint16_t e2fs_max_mnt_count; /* max mount count */
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uint16_t e2fs_magic; /* magic number */
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uint16_t e2fs_state; /* file system state */
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uint16_t e2fs_beh; /* behavior on errors */
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uint16_t e2fs_minrev; /* minor revision level */
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uint32_t e2fs_lastfsck; /* time of last fsck */
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uint32_t e2fs_fsckintv; /* max time between fscks */
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uint32_t e2fs_creator; /* creator OS */
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uint32_t e2fs_rev; /* revision level */
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uint16_t e2fs_ruid; /* default uid for reserved blocks */
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uint16_t e2fs_rgid; /* default gid for reserved blocks */
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/* EXT2_DYNAMIC_REV superblocks */
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uint32_t e2fs_first_ino; /* first non-reserved inode */
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uint16_t e2fs_inode_size; /* size of inode structure */
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uint16_t e2fs_block_group_nr; /* block grp number of this sblk*/
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uint32_t e2fs_features_compat; /* compatible feature set */
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uint32_t e2fs_features_incompat; /* incompatible feature set */
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uint32_t e2fs_features_rocompat; /* RO-compatible feature set */
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uint8_t e2fs_uuid[16]; /* 128-bit uuid for volume */
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char e2fs_vname[16]; /* volume name */
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char e2fs_fsmnt[64]; /* name mounted on */
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uint32_t e2fs_algo; /* For compression */
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uint8_t e2fs_prealloc; /* # of blocks for old prealloc */
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uint8_t e2fs_dir_prealloc; /* # of blocks for old prealloc dirs */
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uint16_t e2fs_reserved_ngdb; /* # of reserved gd blocks for resize */
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char e3fs_journal_uuid[16]; /* uuid of journal superblock */
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uint32_t e3fs_journal_inum; /* inode number of journal file */
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uint32_t e3fs_journal_dev; /* device number of journal file */
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uint32_t e3fs_last_orphan; /* start of list of inodes to delete */
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uint32_t e3fs_hash_seed[4]; /* HTREE hash seed */
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char e3fs_def_hash_version; /* Default hash version to use */
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char e3fs_reserved_char_pad;
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uint32_t e3fs_default_mount_opts;
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uint32_t e3fs_first_meta_bg; /* First metablock block group */
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uint32_t e3fs_mkfs_time; /* when the fs was created */
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uint32_t e3fs_jnl_blks[17]; /* backup of the journal inode */
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uint32_t e4fs_bcount_hi; /* block count */
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uint32_t e4fs_rbcount_hi; /* reserved blocks count */
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uint32_t e4fs_fbcount_hi; /* free blocks count */
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uint16_t e4fs_min_extra_isize;/* all inodes have at least some bytes */
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uint16_t e4fs_want_extra_isize; /* inodes must reserve some bytes */
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uint32_t e4fs_flags; /* miscellaneous flags */
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uint16_t e4fs_raid_stride; /* RAID stride */
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uint16_t e4fs_mmpintv; /* number of seconds to wait in MMP checking */
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uint64_t e4fs_mmpblk; /* block for multi-mount protection */
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uint32_t e4fs_raid_stripe_wid;/* blocks on all data disks (N * stride) */
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uint8_t e4fs_log_gpf; /* FLEX_BG group size */
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uint8_t e4fs_char_pad2;
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uint16_t e4fs_pad;
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uint32_t reserved2[162]; /* Padding to the end of the block */
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};
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/*
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* In-Memory Superblock
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*/
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struct m_ext2fs {
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struct ext2fs * e2fs;
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char e2fs_fsmnt[MAXMNTLEN];/* name mounted on */
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char e2fs_ronly; /* mounted read-only flag */
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char e2fs_fmod; /* super block modified flag */
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uint32_t e2fs_bsize; /* Block size */
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uint32_t e2fs_bshift; /* calc of logical block no */
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uint32_t e2fs_bpg; /* Number of blocks per group */
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int64_t e2fs_qbmask; /* = s_blocksize -1 */
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uint32_t e2fs_fsbtodb; /* Shift to get disk block */
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uint32_t e2fs_ipg; /* Number of inodes per group */
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uint32_t e2fs_ipb; /* Number of inodes per block */
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uint32_t e2fs_itpg; /* Number of inode table per group */
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uint32_t e2fs_fsize; /* Size of fragments per block */
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uint32_t e2fs_fpb; /* Number of fragments per block */
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uint32_t e2fs_fpg; /* Number of fragments per group */
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uint32_t e2fs_gdbcount; /* Number of group descriptors */
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uint32_t e2fs_gcount; /* Number of groups */
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uint32_t e2fs_isize; /* Size of inode */
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uint32_t e2fs_total_dir; /* Total number of directories */
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uint8_t *e2fs_contigdirs; /* (u) # of contig. allocated dirs */
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char e2fs_wasvalid; /* valid at mount time */
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off_t e2fs_maxfilesize;
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struct ext2_gd *e2fs_gd; /* Group Descriptors */
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int32_t e2fs_contigsumsize; /* size of cluster summary array */
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int32_t *e2fs_maxcluster; /* max cluster in each cyl group */
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struct csum *e2fs_clustersum; /* cluster summary in each cyl group */
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};
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/*
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* The second extended file system version
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*/
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#define E2FS_DATE "95/08/09"
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#define E2FS_VERSION "0.5b"
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/*
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* The second extended file system magic number
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*/
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#define E2FS_MAGIC 0xEF53
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/*
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* Revision levels
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*/
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#define E2FS_REV0 0 /* The good old (original) format */
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#define E2FS_REV1 1 /* V2 format w/ dynamic inode sizes */
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#define E2FS_CURRENT_REV E2FS_REV0
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#define E2FS_MAX_SUPP_REV E2FS_REV1
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#define E2FS_REV0_INODE_SIZE 128
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/*
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* compatible/incompatible features
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*/
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#define EXT2F_COMPAT_PREALLOC 0x0001
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#define EXT2F_COMPAT_HASJOURNAL 0x0004
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#define EXT2F_COMPAT_RESIZE 0x0010
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#define EXT2F_COMPAT_DIRHASHINDEX 0x0020
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#define EXT2F_ROCOMPAT_SPARSESUPER 0x0001
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#define EXT2F_ROCOMPAT_LARGEFILE 0x0002
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#define EXT2F_ROCOMPAT_BTREE_DIR 0x0004
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#define EXT2F_ROCOMPAT_HUGE_FILE 0x0008
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#define EXT2F_ROCOMPAT_GDT_CSUM 0x0010
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#define EXT2F_ROCOMPAT_DIR_NLINK 0x0020
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#define EXT2F_ROCOMPAT_EXTRA_ISIZE 0x0040
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#define EXT2F_INCOMPAT_COMP 0x0001
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#define EXT2F_INCOMPAT_FTYPE 0x0002
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#define EXT2F_INCOMPAT_META_BG 0x0010
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#define EXT2F_INCOMPAT_EXTENTS 0x0040
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#define EXT2F_INCOMPAT_64BIT 0x0080
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#define EXT2F_INCOMPAT_MMP 0x0100
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#define EXT2F_INCOMPAT_FLEX_BG 0x0200
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/*
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* Features supported in this implementation
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*
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* We support the following REV1 features:
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* - EXT2F_ROCOMPAT_SPARSESUPER
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* - EXT2F_ROCOMPAT_LARGEFILE
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* - EXT2F_INCOMPAT_FTYPE
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*/
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#define EXT2F_COMPAT_SUPP 0x0000
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#define EXT2F_ROCOMPAT_SUPP (EXT2F_ROCOMPAT_SPARSESUPER | \
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EXT2F_ROCOMPAT_LARGEFILE | \
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EXT2F_ROCOMPAT_EXTRA_ISIZE)
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#define EXT2F_INCOMPAT_SUPP EXT2F_INCOMPAT_FTYPE
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/* Assume that user mode programs are passing in an ext2fs superblock, not
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* a kernel struct super_block. This will allow us to call the feature-test
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* macros from user land. */
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#define EXT2_SB(sb) (sb)
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/*
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* Feature set definitions
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*/
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#define EXT2_HAS_COMPAT_FEATURE(sb,mask) \
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( EXT2_SB(sb)->e2fs->e2fs_features_compat & htole32(mask) )
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#define EXT2_HAS_RO_COMPAT_FEATURE(sb,mask) \
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( EXT2_SB(sb)->e2fs->e2fs_features_rocompat & htole32(mask) )
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#define EXT2_HAS_INCOMPAT_FEATURE(sb,mask) \
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( EXT2_SB(sb)->e2fs->e2fs_features_incompat & htole32(mask) )
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/*
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* Definitions of behavior on errors
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*/
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#define E2FS_BEH_CONTINUE 1 /* continue operation */
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#define E2FS_BEH_READONLY 2 /* remount fs read only */
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#define E2FS_BEH_PANIC 3 /* cause panic */
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#define E2FS_BEH_DEFAULT E2FS_BEH_CONTINUE
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/*
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* OS identification
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*/
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#define E2FS_OS_LINUX 0
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#define E2FS_OS_HURD 1
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#define E2FS_OS_MASIX 2
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#define E2FS_OS_FREEBSD 3
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#define E2FS_OS_LITES 4
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/*
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* File clean flags
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*/
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#define E2FS_ISCLEAN 0x0001 /* Unmounted cleanly */
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#define E2FS_ERRORS 0x0002 /* Errors detected */
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/* ext2 file system block group descriptor */
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struct ext2_gd {
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uint32_t ext2bgd_b_bitmap; /* blocks bitmap block */
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uint32_t ext2bgd_i_bitmap; /* inodes bitmap block */
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uint32_t ext2bgd_i_tables; /* inodes table block */
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uint16_t ext2bgd_nbfree; /* number of free blocks */
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uint16_t ext2bgd_nifree; /* number of free inodes */
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uint16_t ext2bgd_ndirs; /* number of directories */
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uint16_t ext2bgd_flags; /* block group flags */
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uint32_t ext2bgd_x_bitmap; /* snapshot exclusion bitmap loc. */
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uint16_t ext2bgd_b_bmap_csum; /* block bitmap checksum */
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uint16_t ext2bgd_i_bmap_csum; /* inode bitmap checksum */
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uint16_t ext2bgd_i_unused; /* unused inode count */
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uint16_t ext2bgd_csum; /* group descriptor checksum */
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};
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/* cluster summary information */
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struct csum {
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int8_t cs_init; /* cluster summary has been initialized */
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int32_t *cs_sum; /* cluster summary array */
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};
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/* EXT2FS metadatas are stored in little-endian byte order. These macros
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* helps reading these metadatas
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*/
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#define e2fs_cgload(old, new, size) memcpy((new), (old), (size));
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#define e2fs_cgsave(old, new, size) memcpy((new), (old), (size));
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/*
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* Macro-instructions used to manage several block sizes
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*/
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#define EXT2_MAX_BLOCK_SIZE 4096
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#define EXT2_MIN_BLOCK_LOG_SIZE 10
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#define EXT2_BLOCK_SIZE(s) ((s)->e2fs_bsize)
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#define EXT2_ADDR_PER_BLOCK(s) (EXT2_BLOCK_SIZE(s) / sizeof(uint32_t))
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#define EXT2_INODE_SIZE(s) (EXT2_SB(s)->e2fs_isize)
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/*
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* Macro-instructions used to manage fragments
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*/
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#define EXT2_MIN_FRAG_SIZE 1024
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#define EXT2_MAX_FRAG_SIZE 4096
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#define EXT2_MIN_FRAG_LOG_SIZE 10
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#define EXT2_FRAG_SIZE(s) (EXT2_SB(s)->e2fs_fsize)
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#define EXT2_FRAGS_PER_BLOCK(s) (EXT2_SB(s)->e2fs_fpb)
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/*
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* Macro-instructions used to manage group descriptors
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*/
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#define EXT2_BLOCKS_PER_GROUP(s) (EXT2_SB(s)->e2fs_bpg)
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#endif /* !_FS_EXT2FS_EXT2FS_H_ */
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