freebsd-skq/sys/fs/ext2fs/ext2fs.h
lulf 8ab7715033 Bring in the ext2fs work done by Aditya Sarawgi during and after Google Summer
of Code 2009:

- BSDL block and inode allocation policies for ext2fs. This involves the use
  FFS1 style block and inode allocation for ext2fs. Preallocation was removed
  since it was GPL'd.
- Make ext2fs MPSAFE by introducing locks to per-mount datastructures.
- Fixes for kern/122047 PR.
- Various small bugfixes.
- Move out of gnu/ directory.

Sponsored by:   Google Inc.
Submitted by:	Aditya Sarawgi <sarawgi.aditya AT SPAMFREE gmail DOT com>
2010-01-14 14:30:54 +00:00

330 lines
11 KiB
C
Executable File

/*-
* 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_EXT2_FS_H
#define _FS_EXT2FS_EXT2_FS_H
#include <sys/types.h>
/*
* Special inode numbers
*/
#define EXT2_BAD_INO 1 /* Bad blocks inode */
#define EXT2_ROOT_INO 2 /* Root inode */
#define EXT2_BOOT_LOADER_INO 5 /* Boot loader inode */
#define EXT2_UNDEL_DIR_INO 6 /* Undelete directory inode */
/* First non-reserved inode for old ext2 filesystems */
#define E2FS_REV0_FIRST_INO 11
/*
* The second extended file system magic number
*/
#define E2FS_MAGIC 0xEF53
#if defined(_KERNEL)
/*
* FreeBSD passes the pointer to the in-core struct with relevant
* fields to EXT2_SB macro when accessing superblock fields.
*/
#define EXT2_SB(sb) (sb)
#else
/* 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)
#endif
/*
* Maximal count of links to a file
*/
#define EXT2_LINK_MAX 32000
/*
* Constants relative to the data blocks
*/
#define EXT2_NDIR_BLOCKS 12
#define EXT2_IND_BLOCK EXT2_NDIR_BLOCKS
#define EXT2_DIND_BLOCK (EXT2_IND_BLOCK + 1)
#define EXT2_TIND_BLOCK (EXT2_DIND_BLOCK + 1)
#define EXT2_N_BLOCKS (EXT2_TIND_BLOCK + 1)
#define EXT2_MAXSYMLINKLEN (EXT2_N_BLOCKS * sizeof (uint32_t))
/*
* 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
/*
* Super block for an ext2fs file system.
*/
struct ext2fs {
u_int32_t e2fs_icount; /* Inode count */
u_int32_t e2fs_bcount; /* blocks count */
u_int32_t e2fs_rbcount; /* reserved blocks count */
u_int32_t e2fs_fbcount; /* free blocks count */
u_int32_t e2fs_ficount; /* free inodes count */
u_int32_t e2fs_first_dblock; /* first data block */
u_int32_t e2fs_log_bsize; /* block size = 1024*(2^e2fs_log_bsize) */
u_int32_t e2fs_log_fsize; /* fragment size */
u_int32_t e2fs_bpg; /* blocks per group */
u_int32_t e2fs_fpg; /* frags per group */
u_int32_t e2fs_ipg; /* inodes per group */
u_int32_t e2fs_mtime; /* mount time */
u_int32_t e2fs_wtime; /* write time */
u_int16_t e2fs_mnt_count; /* mount count */
u_int16_t e2fs_max_mnt_count; /* max mount count */
u_int16_t e2fs_magic; /* magic number */
u_int16_t e2fs_state; /* file system state */
u_int16_t e2fs_beh; /* behavior on errors */
u_int16_t e2fs_minrev; /* minor revision level */
u_int32_t e2fs_lastfsck; /* time of last fsck */
u_int32_t e2fs_fsckintv; /* max time between fscks */
u_int32_t e2fs_creator; /* creator OS */
u_int32_t e2fs_rev; /* revision level */
u_int16_t e2fs_ruid; /* default uid for reserved blocks */
u_int16_t e2fs_rgid; /* default gid for reserved blocks */
/* EXT2_DYNAMIC_REV superblocks */
u_int32_t e2fs_first_ino; /* first non-reserved inode */
u_int16_t e2fs_inode_size; /* size of inode structure */
u_int16_t e2fs_block_group_nr; /* block grp number of this sblk*/
u_int32_t e2fs_features_compat; /* compatible feature set */
u_int32_t e2fs_features_incompat; /* incompatible feature set */
u_int32_t e2fs_features_rocompat; /* RO-compatible feature set */
u_int8_t e2fs_uuid[16]; /* 128-bit uuid for volume */
char e2fs_vname[16]; /* volume name */
char e2fs_fsmnt[64]; /* name mounted on */
u_int32_t e2fs_algo; /* For comcate for dir */
u_int16_t e2fs_reserved_ngdb; /* # of reserved gd blocks for resize */
u_int32_t reserved2[204];
};
/* 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)
/*
* 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 */
int32_t e2fs_bmask; /* calc of block offset */
int32_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_dbpg; /* Number of descriptor blocks per group */
uint32_t e2fs_descpb; /* Number of group descriptors per block */
uint32_t e2fs_gdbcount; /* Number of group descriptors */
uint32_t e2fs_gcount; /* Number of groups */
uint32_t e2fs_first_inode;/* First inode on fs */
int32_t e2fs_isize; /* Size of inode */
uint32_t e2fs_mount_opt;
uint32_t e2fs_blocksize_bits;
uint32_t e2fs_total_dir; /* Total number of directories */
uint8_t *e2fs_contigdirs;
char e2fs_wasvalid; /* valid at mount time */
off_t e2fs_maxfilesize;
struct ext2_gd *e2fs_gd; /* Group Descriptors */
};
/*
* The second extended file system version
*/
#define E2FS_DATE "95/08/09"
#define E2FS_VERSION "0.5b"
/*
* Revision levels
*/
#define E2FS_REV0 0 /* The good old (original) format */
#define E2FS_REV1 1 /* V2 format w/ dynamic inode sizes */
#define E2FS_CURRENT_REV E2FS_REV0
#define E2FS_MAX_SUPP_REV E2FS_REV1
#define E2FS_REV0_INODE_SIZE 128
/*
* compatible/incompatible features
*/
#define EXT2F_COMPAT_PREALLOC 0x0001
#define EXT2F_COMPAT_RESIZE 0x0010
#define EXT2F_ROCOMPAT_SPARSESUPER 0x0001
#define EXT2F_ROCOMPAT_LARGEFILE 0x0002
#define EXT2F_ROCOMPAT_BTREE_DIR 0x0004
#define EXT2F_INCOMPAT_COMP 0x0001
#define EXT2F_INCOMPAT_FTYPE 0x0002
/*
* Features supported in this implementation
*
* We support the following REV1 features:
* - EXT2F_ROCOMPAT_SPARSESUPER
* - EXT2F_ROCOMPAT_LARGEFILE
* - EXT2F_INCOMPAT_FTYPE
*/
#define EXT2F_COMPAT_SUPP 0x0000
#define EXT2F_ROCOMPAT_SUPP (EXT2F_ROCOMPAT_SPARSESUPER \
| EXT2F_ROCOMPAT_LARGEFILE)
#define EXT2F_INCOMPAT_SUPP EXT2F_INCOMPAT_FTYPE
/*
* 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) )
/*
* Definitions of behavior on errors
*/
#define E2FS_BEH_CONTINUE 1 /* continue operation */
#define E2FS_BEH_READONLY 2 /* remount fs read only */
#define E2FS_BEH_PANIC 3 /* cause panic */
#define E2FS_BEH_DEFAULT E2FS_BEH_CONTINUE
/*
* OS identification
*/
#define E2FS_OS_LINUX 0
#define E2FS_OS_HURD 1
#define E2FS_OS_MASIX 2
#define E2FS_OS_FREEBSD 3
#define E2FS_OS_LITES 4
/*
* File clean flags
*/
#define E2FS_ISCLEAN 0x0001 /* Unmounted cleanly */
#define E2FS_ERRORS 0x0002 /* Errors detected */
/* ext2 file system block group descriptor */
struct ext2_gd {
u_int32_t ext2bgd_b_bitmap; /* blocks bitmap block */
u_int32_t ext2bgd_i_bitmap; /* inodes bitmap block */
u_int32_t ext2bgd_i_tables; /* inodes table block */
u_int16_t ext2bgd_nbfree; /* number of free blocks */
u_int16_t ext2bgd_nifree; /* number of free inodes */
u_int16_t ext2bgd_ndirs; /* number of directories */
u_int16_t reserved;
u_int32_t reserved2[3];
};
/* 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_MIN_BLOCK_SIZE 1024
#define EXT2_MAX_BLOCK_SIZE 4096
#define EXT2_MIN_BLOCK_LOG_SIZE 10
#if defined(_KERNEL)
# define EXT2_BLOCK_SIZE(s) ((s)->e2fs_bsize)
#else
# define EXT2_BLOCK_SIZE(s) (EXT2_MIN_BLOCK_SIZE << (s)->e2fs_log_bsize)
#endif
#define EXT2_ADDR_PER_BLOCK(s) (EXT2_BLOCK_SIZE(s) / sizeof (uint32_t))
#if defined(_KERNEL)
# define EXT2_BLOCK_SIZE_BITS(s) ((s)->e2fs_blocksize_bits)
#else
# define EXT2_BLOCK_SIZE_BITS(s) ((s)->e2fs_log_bsize + 10)
#endif
#if defined(_KERNEL)
#define EXT2_ADDR_PER_BLOCK_BITS(s) (EXT2_SB(s)->s_addr_per_block_bits)
#define EXT2_INODE_SIZE(s) (EXT2_SB(s)->e2fs_isize)
#define EXT2_FIRST_INO(s) (EXT2_SB(s)->e2fs_first_inode)
#else
#define EXT2_INODE_SIZE(s) (((s)->s_rev_level == E2FS_REV0) ? \
E2FS_REV0 : (s)->s_inode_size)
#define EXT2_FIRST_INO(s) (((s)->s_rev_level == E2FS_REV0) ? \
E2FS_REV0 : (s)->e2fs_first_ino)
#endif
/*
* 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
#if defined(_KERNEL)
# define EXT2_FRAG_SIZE(s) (EXT2_SB(s)->e2fs_fsize)
# define EXT2_FRAGS_PER_BLOCK(s) (EXT2_SB(s)->e2fs_fpb)
#else
# define EXT2_FRAG_SIZE(s) (EXT2_MIN_FRAG_SIZE << (s)->e2fs_log_fsize)
# define EXT2_FRAGS_PER_BLOCK(s) (EXT2_BLOCK_SIZE(s) / EXT2_FRAG_SIZE(s))
#endif
/*
* Macro-instructions used to manage group descriptors
*/
#if defined(_KERNEL)
# define EXT2_BLOCKS_PER_GROUP(s) (EXT2_SB(s)->e2fs_bpg)
# define EXT2_DESC_PER_BLOCK(s) (EXT2_SB(s)->e2fs_descpb)
# define EXT2_DESC_PER_BLOCK_BITS(s) (EXT2_SB(s)->s_desc_per_block_bits)
#else
# define EXT2_BLOCKS_PER_GROUP(s) ((s)->e2fs_bpg)
# define EXT2_DESC_PER_BLOCK(s) (EXT2_BLOCK_SIZE(s) / sizeof (struct ext2_gd))
#endif
#endif /* _LINUX_EXT2_FS_H */