freebsd-nq/sys/fs/ext2fs/ext2fs.h
2016-03-28 07:44:55 +00:00

332 lines
13 KiB
C

/*-
* modified for EXT2FS support in Lites 1.1
*
* Aug 1995, Godmar Back (gback@cs.utah.edu)
* University of Utah, Department of Computer Science
*
* $FreeBSD$
*/
/*-
* Copyright (c) 2009 Aditya Sarawgi
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*
*
*/
#ifndef _FS_EXT2FS_EXT2FS_H_
#define _FS_EXT2FS_EXT2FS_H_
#include <sys/types.h>
/*
* Super block for an ext2fs file system.
*/
struct ext2fs {
uint32_t e2fs_icount; /* Inode count */
uint32_t e2fs_bcount; /* blocks count */
uint32_t e2fs_rbcount; /* reserved blocks count */
uint32_t e2fs_fbcount; /* free blocks count */
uint32_t e2fs_ficount; /* free inodes count */
uint32_t e2fs_first_dblock; /* first data block */
uint32_t e2fs_log_bsize; /* block size = 1024*(2^e2fs_log_bsize) */
uint32_t e2fs_log_fsize; /* fragment size */
uint32_t e2fs_bpg; /* blocks per group */
uint32_t e2fs_fpg; /* frags per group */
uint32_t e2fs_ipg; /* inodes per group */
uint32_t e2fs_mtime; /* mount time */
uint32_t e2fs_wtime; /* write time */
uint16_t e2fs_mnt_count; /* mount count */
uint16_t e2fs_max_mnt_count; /* max mount count */
uint16_t e2fs_magic; /* magic number */
uint16_t e2fs_state; /* file system state */
uint16_t e2fs_beh; /* behavior on errors */
uint16_t e2fs_minrev; /* minor revision level */
uint32_t e2fs_lastfsck; /* time of last fsck */
uint32_t e2fs_fsckintv; /* max time between fscks */
uint32_t e2fs_creator; /* creator OS */
uint32_t e2fs_rev; /* revision level */
uint16_t e2fs_ruid; /* default uid for reserved blocks */
uint16_t e2fs_rgid; /* default gid for reserved blocks */
/* EXT2_DYNAMIC_REV superblocks */
uint32_t e2fs_first_ino; /* first non-reserved inode */
uint16_t e2fs_inode_size; /* size of inode structure */
uint16_t e2fs_block_group_nr; /* block grp number of this sblk*/
uint32_t e2fs_features_compat; /* compatible feature set */
uint32_t e2fs_features_incompat; /* incompatible feature set */
uint32_t e2fs_features_rocompat; /* RO-compatible feature set */
uint8_t e2fs_uuid[16]; /* 128-bit uuid for volume */
char e2fs_vname[16]; /* volume name */
char e2fs_fsmnt[64]; /* name mounted on */
uint32_t e2fs_algo; /* For compression */
uint8_t e2fs_prealloc; /* # of blocks for old prealloc */
uint8_t e2fs_dir_prealloc; /* # of blocks for old prealloc dirs */
uint16_t e2fs_reserved_ngdb; /* # of reserved gd blocks for resize */
char e3fs_journal_uuid[16]; /* uuid of journal superblock */
uint32_t e3fs_journal_inum; /* inode number of journal file */
uint32_t e3fs_journal_dev; /* device number of journal file */
uint32_t e3fs_last_orphan; /* start of list of inodes to delete */
uint32_t e3fs_hash_seed[4]; /* HTREE hash seed */
char e3fs_def_hash_version; /* Default hash version to use */
char e3fs_jnl_backup_type;
uint16_t e3fs_desc_size; /* size of group descriptor */
uint32_t e3fs_default_mount_opts;
uint32_t e3fs_first_meta_bg; /* First metablock block group */
uint32_t e3fs_mkfs_time; /* when the fs was created */
uint32_t e3fs_jnl_blks[17]; /* backup of the journal inode */
uint32_t e4fs_bcount_hi; /* high bits of blocks count */
uint32_t e4fs_rbcount_hi; /* high bits of reserved blocks count */
uint32_t e4fs_fbcount_hi; /* high bits of free blocks count */
uint16_t e4fs_min_extra_isize; /* all inodes have at least some bytes */
uint16_t e4fs_want_extra_isize; /* inodes must reserve some bytes */
uint32_t e4fs_flags; /* miscellaneous flags */
uint16_t e4fs_raid_stride; /* RAID stride */
uint16_t e4fs_mmpintv; /* number of seconds to wait in MMP checking */
uint64_t e4fs_mmpblk; /* block for multi-mount protection */
uint32_t e4fs_raid_stripe_wid; /* blocks on all data disks (N * stride) */
uint8_t e4fs_log_gpf; /* FLEX_BG group size */
uint8_t e4fs_chksum_type; /* metadata checksum algorithm used */
uint8_t e4fs_encrypt; /* versioning level for encryption */
uint8_t e4fs_reserved_pad;
uint64_t e4fs_kbytes_written; /* number of lifetime kilobytes */
uint32_t e4fs_snapinum; /* inode number of active snapshot */
uint32_t e4fs_snapid; /* sequential ID of active snapshot */
uint64_t e4fs_snaprbcount; /* reserved blocks for active snapshot */
uint32_t e4fs_snaplist; /* inode number for on-disk snapshot */
uint32_t e4fs_errcount; /* number of file system errors */
uint32_t e4fs_first_errtime; /* first time an error happened */
uint32_t e4fs_first_errino; /* inode involved in first error */
uint64_t e4fs_first_errblk; /* block involved of first error */
uint8_t e4fs_first_errfunc[32]; /* function where error happened */
uint32_t e4fs_first_errline; /* line number where error happened */
uint32_t e4fs_last_errtime; /* most recent time of an error */
uint32_t e4fs_last_errino; /* inode involved in last error */
uint32_t e4fs_last_errline; /* line number where error happened */
uint64_t e4fs_last_errblk; /* block involved of last error */
uint8_t e4fs_last_errfunc[32]; /* function where error happened */
uint8_t e4fs_mount_opts[64];
uint32_t e4fs_usrquota_inum; /* inode for tracking user quota */
uint32_t e4fs_grpquota_inum; /* inode for tracking group quota */
uint32_t e4fs_overhead_clusters; /* overhead blocks/clusters */
uint32_t e4fs_backup_bgs[2]; /* groups with sparse_super2 SBs */
uint8_t e4fs_encrypt_algos[4]; /* encryption algorithms in use */
uint8_t e4fs_encrypt_pw_salt[16]; /* salt used for string2key */
uint32_t e4fs_lpf_ino; /* location of the lost+found inode */
uint32_t e4fs_proj_quota_inum; /* inode for tracking project quota */
uint32_t e4fs_chksum_seed; /* checksum seed */
uint32_t e4fs_reserved[98]; /* padding to the end of the block */
uint32_t e4fs_sbchksum; /* superblock checksum */
};
/*
* The path name on which the file system is mounted is maintained
* in fs_fsmnt. MAXMNTLEN defines the amount of space allocated in
* the super block for this name.
*/
#define MAXMNTLEN 512
/*
* In-Memory Superblock
*/
struct m_ext2fs {
struct ext2fs * e2fs;
char e2fs_fsmnt[MAXMNTLEN];/* name mounted on */
char e2fs_ronly; /* mounted read-only flag */
char e2fs_fmod; /* super block modified flag */
uint32_t e2fs_bsize; /* Block size */
uint32_t e2fs_bshift; /* calc of logical block no */
uint32_t e2fs_bpg; /* Number of blocks per group */
int64_t e2fs_qbmask; /* = s_blocksize -1 */
uint32_t e2fs_fsbtodb; /* Shift to get disk block */
uint32_t e2fs_ipg; /* Number of inodes per group */
uint32_t e2fs_ipb; /* Number of inodes per block */
uint32_t e2fs_itpg; /* Number of inode table per group */
uint32_t e2fs_fsize; /* Size of fragments per block */
uint32_t e2fs_fpb; /* Number of fragments per block */
uint32_t e2fs_fpg; /* Number of fragments per group */
uint32_t e2fs_gdbcount; /* Number of group descriptors */
uint32_t e2fs_gcount; /* Number of groups */
uint32_t e2fs_isize; /* Size of inode */
uint32_t e2fs_total_dir; /* Total number of directories */
uint8_t *e2fs_contigdirs; /* (u) # of contig. allocated dirs */
char e2fs_wasvalid; /* valid at mount time */
off_t e2fs_maxfilesize;
struct ext2_gd *e2fs_gd; /* Group Descriptors */
int32_t e2fs_contigsumsize; /* size of cluster summary array */
int32_t *e2fs_maxcluster; /* max cluster in each cyl group */
struct csum *e2fs_clustersum; /* cluster summary in each cyl group */
int32_t e2fs_uhash; /* 3 if hash should be signed, 0 if not */
};
/* cluster summary information */
struct csum {
int8_t cs_init; /* cluster summary has been initialized */
int32_t *cs_sum; /* cluster summary array */
};
/*
* The second extended file system magic number
*/
#define E2FS_MAGIC 0xEF53
/*
* Revision levels
*/
#define E2FS_REV0 0 /* The good old (original) format */
#define E2FS_REV1 1 /* V2 format w/ dynamic inode sizes */
#define E2FS_REV0_INODE_SIZE 128
/*
* compatible/incompatible features
*/
#define EXT2F_COMPAT_PREALLOC 0x0001
#define EXT2F_COMPAT_HASJOURNAL 0x0004
#define EXT2F_COMPAT_RESIZE 0x0010
#define EXT2F_COMPAT_DIRHASHINDEX 0x0020
#define EXT2F_ROCOMPAT_SPARSESUPER 0x0001
#define EXT2F_ROCOMPAT_LARGEFILE 0x0002
#define EXT2F_ROCOMPAT_BTREE_DIR 0x0004
#define EXT2F_ROCOMPAT_HUGE_FILE 0x0008
#define EXT2F_ROCOMPAT_GDT_CSUM 0x0010
#define EXT2F_ROCOMPAT_DIR_NLINK 0x0020
#define EXT2F_ROCOMPAT_EXTRA_ISIZE 0x0040
#define EXT2F_INCOMPAT_COMP 0x0001
#define EXT2F_INCOMPAT_FTYPE 0x0002
#define EXT2F_INCOMPAT_RECOVER 0x0004
#define EXT2F_INCOMPAT_META_BG 0x0010
#define EXT2F_INCOMPAT_EXTENTS 0x0040
#define EXT2F_INCOMPAT_64BIT 0x0080
#define EXT2F_INCOMPAT_MMP 0x0100
#define EXT2F_INCOMPAT_FLEX_BG 0x0200
/*
* Features supported in this implementation
*
* We support the following REV1 features:
* - EXT2F_ROCOMPAT_SPARSESUPER
* - EXT2F_ROCOMPAT_LARGEFILE
* - EXT2F_ROCOMPAT_EXTRA_ISIZE
* - EXT2F_INCOMPAT_FTYPE
*
* We partially (read-only) support the following EXT4 features:
* - EXT2F_ROCOMPAT_HUGE_FILE
* - EXT2F_INCOMPAT_EXTENTS
*
* We do not support these EXT4 features but they are irrelevant
* for read-only support:
* - EXT2F_INCOMPAT_RECOVER
* - EXT2F_INCOMPAT_FLEX_BG
* - EXT2F_INCOMPAT_META_BG
*/
#define EXT2F_COMPAT_SUPP EXT2F_COMPAT_DIRHASHINDEX
#define EXT2F_ROCOMPAT_SUPP (EXT2F_ROCOMPAT_SPARSESUPER | \
EXT2F_ROCOMPAT_LARGEFILE | \
EXT2F_ROCOMPAT_EXTRA_ISIZE)
#define EXT2F_INCOMPAT_SUPP EXT2F_INCOMPAT_FTYPE
#define EXT4F_RO_INCOMPAT_SUPP (EXT2F_INCOMPAT_EXTENTS | \
EXT2F_INCOMPAT_RECOVER | \
EXT2F_INCOMPAT_FLEX_BG | \
EXT2F_INCOMPAT_META_BG )
/* Assume that user mode programs are passing in an ext2fs superblock, not
* a kernel struct super_block. This will allow us to call the feature-test
* macros from user land. */
#define EXT2_SB(sb) (sb)
/*
* Feature set definitions
*/
#define EXT2_HAS_COMPAT_FEATURE(sb,mask) \
( EXT2_SB(sb)->e2fs->e2fs_features_compat & htole32(mask) )
#define EXT2_HAS_RO_COMPAT_FEATURE(sb,mask) \
( EXT2_SB(sb)->e2fs->e2fs_features_rocompat & htole32(mask) )
#define EXT2_HAS_INCOMPAT_FEATURE(sb,mask) \
( EXT2_SB(sb)->e2fs->e2fs_features_incompat & htole32(mask) )
/*
* File clean flags
*/
#define E2FS_ISCLEAN 0x0001 /* Unmounted cleanly */
#define E2FS_ERRORS 0x0002 /* Errors detected */
/*
* Filesystem miscellaneous flags
*/
#define E2FS_SIGNED_HASH 0x0001
#define E2FS_UNSIGNED_HASH 0x0002
/* ext2 file system block group descriptor */
struct ext2_gd {
uint32_t ext2bgd_b_bitmap; /* blocks bitmap block */
uint32_t ext2bgd_i_bitmap; /* inodes bitmap block */
uint32_t ext2bgd_i_tables; /* inodes table block */
uint16_t ext2bgd_nbfree; /* number of free blocks */
uint16_t ext2bgd_nifree; /* number of free inodes */
uint16_t ext2bgd_ndirs; /* number of directories */
uint16_t ext4bgd_flags; /* block group flags */
uint32_t ext4bgd_x_bitmap; /* snapshot exclusion bitmap loc. */
uint16_t ext4bgd_b_bmap_csum; /* block bitmap checksum */
uint16_t ext4bgd_i_bmap_csum; /* inode bitmap checksum */
uint16_t ext4bgd_i_unused; /* unused inode count */
uint16_t ext4bgd_csum; /* group descriptor checksum */
};
/* EXT2FS metadatas are stored in little-endian byte order. These macros
* helps reading these metadatas
*/
#define e2fs_cgload(old, new, size) memcpy((new), (old), (size));
#define e2fs_cgsave(old, new, size) memcpy((new), (old), (size));
/*
* Macro-instructions used to manage several block sizes
*/
#define EXT2_MAX_BLOCK_SIZE 4096
#define EXT2_MIN_BLOCK_LOG_SIZE 10
#define EXT2_BLOCK_SIZE(s) ((s)->e2fs_bsize)
#define EXT2_ADDR_PER_BLOCK(s) (EXT2_BLOCK_SIZE(s) / sizeof(uint32_t))
#define EXT2_INODE_SIZE(s) (EXT2_SB(s)->e2fs_isize)
/*
* Macro-instructions used to manage fragments
*/
#define EXT2_MIN_FRAG_SIZE 1024
#define EXT2_MAX_FRAG_SIZE 4096
#define EXT2_MIN_FRAG_LOG_SIZE 10
#define EXT2_FRAG_SIZE(s) (EXT2_SB(s)->e2fs_fsize)
#define EXT2_FRAGS_PER_BLOCK(s) (EXT2_SB(s)->e2fs_fpb)
/*
* Macro-instructions used to manage group descriptors
*/
#define EXT2_BLOCKS_PER_GROUP(s) (EXT2_SB(s)->e2fs_bpg)
#endif /* !_FS_EXT2FS_EXT2FS_H_ */