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/*
* linux/include/linux/ext2_fs.h
*
* Copyright (C) 1992, 1993, 1994, 1995
* Remy Card (card@masi.ibp.fr)
* Laboratoire MASI - Institut Blaise Pascal
* Universite Pierre et Marie Curie (Paris VI)
*
* from
*
* linux/include/linux/minix_fs.h
*
* Copyright (C) 1991, 1992 Linus Torvalds
*/
#ifndef _LINUX_EXT2_FS_H
#define _LINUX_EXT2_FS_H
#include <linux/types.h>
/*
* The second extended filesystem constants/structures
*/
/*
* Define EXT2FS_DEBUG to produce debug messages
*/
#undef EXT2FS_DEBUG
/*
* Define EXT2FS_DEBUG_CACHE to produce cache debug messages
*/
#undef EXT2FS_DEBUG_CACHE
/*
* Define EXT2FS_CHECK_CACHE to add some checks to the name cache code
*/
#undef EXT2FS_CHECK_CACHE
/*
* Define EXT2FS_PRE_02B_COMPAT to convert ext 2 fs prior to 0.2b
*/
#undef EXT2FS_PRE_02B_COMPAT
/*
* Define EXT2_PREALLOCATE to preallocate data blocks for expanding files
*/
#define EXT2_PREALLOCATE
/*
* The second extended file system version
*/
#define EXT2FS_DATE "95/03/19"
#define EXT2FS_VERSION "0.5a"
/*
* Debug code
*/
#ifdef EXT2FS_DEBUG
# define ext2_debug(f, a...) { \
printk ("EXT2-fs DEBUG (%s, %d): %s:", \
__FILE__, __LINE__, __FUNCTION__); \
printk (f, ## a); \
}
#else
# define ext2_debug(f, a...) /**/
#endif
/*
* Special inodes numbers
*/
#define EXT2_BAD_INO 1 /* Bad blocks inode */
#define EXT2_ROOT_INO 2 /* Root inode */
#define EXT2_ACL_IDX_INO 3 /* ACL inode */
#define EXT2_ACL_DATA_INO 4 /* ACL inode */
#define EXT2_BOOT_LOADER_INO 5 /* Boot loader inode */
#define EXT2_UNDEL_DIR_INO 6 /* Undelete directory inode */
#define EXT2_FIRST_INO 11 /* First non reserved inode */
/*
* The second extended file system magic number
*/
#define EXT2_PRE_02B_MAGIC 0xEF51
#define EXT2_SUPER_MAGIC 0xEF53
/*
* Maximal count of links to a file
*/
#define EXT2_LINK_MAX 32000
/*
* 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
#ifdef __KERNEL__
# define EXT2_BLOCK_SIZE(s) ((s)->s_blocksize)
#else
# define EXT2_BLOCK_SIZE(s) (EXT2_MIN_BLOCK_SIZE << (s)->s_log_block_size)
#endif
#define EXT2_ACLE_PER_BLOCK(s) (EXT2_BLOCK_SIZE(s) / sizeof (struct ext2_acl_entry))
#define EXT2_ADDR_PER_BLOCK(s) (EXT2_BLOCK_SIZE(s) / sizeof (__u32))
#ifdef __KERNEL__
# define EXT2_BLOCK_SIZE_BITS(s) ((s)->u.ext2_sb.s_es->s_log_block_size + 10)
#else
# define EXT2_BLOCK_SIZE_BITS(s) ((s)->s_log_block_size + 10)
#endif
#define EXT2_INODES_PER_BLOCK(s) (EXT2_BLOCK_SIZE(s) / sizeof (struct ext2_inode))
/*
* 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
#ifdef __KERNEL__
# define EXT2_FRAG_SIZE(s) ((s)->u.ext2_sb.s_frag_size)
# define EXT2_FRAGS_PER_BLOCK(s) ((s)->u.ext2_sb.s_frags_per_block)
#else
# define EXT2_FRAG_SIZE(s) (EXT2_MIN_FRAG_SIZE << (s)->s_log_frag_size)
# define EXT2_FRAGS_PER_BLOCK(s) (EXT2_BLOCK_SIZE(s) / EXT2_FRAG_SIZE(s))
#endif
/*
* ACL structures
*/
struct ext2_acl_header /* Header of Access Control Lists */
{
__u32 aclh_size;
__u32 aclh_file_count;
__u32 aclh_acle_count;
__u32 aclh_first_acle;
};
struct ext2_acl_entry /* Access Control List Entry */
{
__u32 acle_size;
__u16 acle_perms; /* Access permissions */
__u16 acle_type; /* Type of entry */
__u16 acle_tag; /* User or group identity */
__u16 acle_pad1;
__u32 acle_next; /* Pointer on next entry for the */
/* same inode or on next free entry */
};
/*
* Structure of a blocks group descriptor
*/
struct ext2_old_group_desc
{
__u32 bg_block_bitmap; /* Blocks bitmap block */
__u32 bg_inode_bitmap; /* Inodes bitmap block */
__u32 bg_inode_table; /* Inodes table block */
__u16 bg_free_blocks_count; /* Free blocks count */
__u16 bg_free_inodes_count; /* Free inodes count */
};
struct ext2_group_desc
{
__u32 bg_block_bitmap; /* Blocks bitmap block */
__u32 bg_inode_bitmap; /* Inodes bitmap block */
__u32 bg_inode_table; /* Inodes table block */
__u16 bg_free_blocks_count; /* Free blocks count */
__u16 bg_free_inodes_count; /* Free inodes count */
__u16 bg_used_dirs_count; /* Directories count */
__u16 bg_pad;
__u32 bg_reserved[3];
};
/*
* Macro-instructions used to manage group descriptors
*/
#ifdef __KERNEL__
# define EXT2_BLOCKS_PER_GROUP(s) ((s)->u.ext2_sb.s_blocks_per_group)
# define EXT2_DESC_PER_BLOCK(s) ((s)->u.ext2_sb.s_desc_per_block)
# define EXT2_INODES_PER_GROUP(s) ((s)->u.ext2_sb.s_inodes_per_group)
#else
# define EXT2_BLOCKS_PER_GROUP(s) ((s)->s_blocks_per_group)
# define EXT2_DESC_PER_BLOCK(s) (EXT2_BLOCK_SIZE(s) / sizeof (struct ext2_group_desc))
# define EXT2_INODES_PER_GROUP(s) ((s)->s_inodes_per_group)
#endif
/*
* 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)
/*
* Inode flags
*/
#define EXT2_SECRM_FL 0x00000001 /* Secure deletion */
#define EXT2_UNRM_FL 0x00000002 /* Undelete */
#define EXT2_COMPR_FL 0x00000004 /* Compress file */
#define EXT2_SYNC_FL 0x00000008 /* Synchronous updates */
#define EXT2_IMMUTABLE_FL 0x00000010 /* Immutable file */
#define EXT2_APPEND_FL 0x00000020 /* writes to file may only append */
#define EXT2_NODUMP_FL 0x00000040 /* do not dump file */
/*
* ioctl commands
*/
#define EXT2_IOC_GETFLAGS _IOR('f', 1, long)
#define EXT2_IOC_SETFLAGS _IOW('f', 2, long)
#define EXT2_IOC_GETVERSION _IOR('v', 1, long)
#define EXT2_IOC_SETVERSION _IOW('v', 2, long)
/*
* Structure of an inode on the disk
*/
struct ext2_inode {
__u16 i_mode; /* File mode */
__u16 i_uid; /* Owner Uid */
__u32 i_size; /* Size in bytes */
__u32 i_atime; /* Access time */
__u32 i_ctime; /* Creation time */
__u32 i_mtime; /* Modification time */
__u32 i_dtime; /* Deletion Time */
__u16 i_gid; /* Group Id */
__u16 i_links_count; /* Links count */
__u32 i_blocks; /* Blocks count */
__u32 i_flags; /* File flags */
union {
struct {
__u32 l_i_reserved1;
} linux1;
struct {
__u32 h_i_translator;
} hurd1;
struct {
__u32 m_i_reserved1;
} masix1;
} osd1; /* OS dependent 1 */
__u32 i_block[EXT2_N_BLOCKS];/* Pointers to blocks */
__u32 i_version; /* File version (for NFS) */
__u32 i_file_acl; /* File ACL */
__u32 i_dir_acl; /* Directory ACL */
__u32 i_faddr; /* Fragment address */
union {
struct {
__u8 l_i_frag; /* Fragment number */
__u8 l_i_fsize; /* Fragment size */
__u16 i_pad1;
__u32 l_i_reserved2[2];
} linux2;
struct {
__u8 h_i_frag; /* Fragment number */
__u8 h_i_fsize; /* Fragment size */
__u16 h_i_mode_high;
__u16 h_i_uid_high;
__u16 h_i_gid_high;
__u32 h_i_author;
} hurd2;
struct {
__u8 m_i_frag; /* Fragment number */
__u8 m_i_fsize; /* Fragment size */
__u16 m_pad1;
__u32 m_i_reserved2[2];
} masix2;
} osd2; /* OS dependent 2 */
};
#if defined(__KERNEL__) || defined(__linux__)
#define i_reserved1 osd1.linux1.l_i_reserved1
#define i_frag osd2.linux2.l_i_frag
#define i_fsize osd2.linux2.l_i_fsize
#define i_reserved2 osd2.linux2.l_i_reserved2
#endif
#ifdef __hurd__
#define i_translator osd1.hurd1.h_i_translator
#define i_frag osd2.hurd2.h_i_frag;
#define i_fsize osd2.hurd2.h_i_fsize;
#define i_uid_high osd2.hurd2.h_i_uid_high
#define i_gid_high osd2.hurd2.h_i_gid_high
#define i_mode_high osd2.hurd2.h_i_mode_high
#define i_author osd2.hurd2.h_i_author
#endif
#ifdef __masix__
#define i_reserved1 osd1.masix1.m_i_reserved1
#define i_frag osd2.masix2.m_i_frag
#define i_fsize osd2.masix2.m_i_fsize
#define i_reserved2 osd2.masix2.m_i_reserved2
#endif
/*
* File system states
*/
#define EXT2_VALID_FS 0x0001 /* Unmounted cleanly */
#define EXT2_ERROR_FS 0x0002 /* Errors detected */
/*
* Mount flags
*/
#define EXT2_MOUNT_CHECK_NORMAL 0x0001 /* Do some more checks */
#define EXT2_MOUNT_CHECK_STRICT 0x0002 /* Do again more checks */
#define EXT2_MOUNT_CHECK (EXT2_MOUNT_CHECK_NORMAL | \
EXT2_MOUNT_CHECK_STRICT)
#define EXT2_MOUNT_GRPID 0x0004 /* Create files with directory's group */
#define EXT2_MOUNT_DEBUG 0x0008 /* Some debugging messages */
#define EXT2_MOUNT_ERRORS_CONT 0x0010 /* Continue on errors */
#define EXT2_MOUNT_ERRORS_RO 0x0020 /* Remount fs ro on errors */
#define EXT2_MOUNT_ERRORS_PANIC 0x0040 /* Panic on errors */
#define EXT2_MOUNT_MINIX_DF 0x0080 /* Mimics the Minix statfs */
#define clear_opt(o, opt) o &= ~EXT2_MOUNT_##opt
#define set_opt(o, opt) o |= EXT2_MOUNT_##opt
#define test_opt(sb, opt) ((sb)->u.ext2_sb.s_mount_opt & \
EXT2_MOUNT_##opt)
/*
* Maximal mount counts between two filesystem checks
*/
#define EXT2_DFL_MAX_MNT_COUNT 20 /* Allow 20 mounts */
#define EXT2_DFL_CHECKINTERVAL 0 /* Don't use interval check */
/*
* Behaviour when detecting errors
*/
#define EXT2_ERRORS_CONTINUE 1 /* Continue execution */
#define EXT2_ERRORS_RO 2 /* Remount fs read-only */
#define EXT2_ERRORS_PANIC 3 /* Panic */
#define EXT2_ERRORS_DEFAULT EXT2_ERRORS_CONTINUE
/*
* Structure of the super block
*/
struct ext2_super_block {
__u32 s_inodes_count; /* Inodes count */
__u32 s_blocks_count; /* Blocks count */
__u32 s_r_blocks_count; /* Reserved blocks count */
__u32 s_free_blocks_count; /* Free blocks count */
__u32 s_free_inodes_count; /* Free inodes count */
__u32 s_first_data_block; /* First Data Block */
__u32 s_log_block_size; /* Block size */
__s32 s_log_frag_size; /* Fragment size */
__u32 s_blocks_per_group; /* # Blocks per group */
__u32 s_frags_per_group; /* # Fragments per group */
__u32 s_inodes_per_group; /* # Inodes per group */
__u32 s_mtime; /* Mount time */
__u32 s_wtime; /* Write time */
__u16 s_mnt_count; /* Mount count */
__s16 s_max_mnt_count; /* Maximal mount count */
__u16 s_magic; /* Magic signature */
__u16 s_state; /* File system state */
__u16 s_errors; /* Behaviour when detecting errors */
__u16 s_pad;
__u32 s_lastcheck; /* time of last check */
__u32 s_checkinterval; /* max. time between checks */
__u32 s_creator_os; /* OS */
__u32 s_rev_level; /* Revision level */
__u16 s_def_resuid; /* Default uid for reserved blocks */
__u16 s_def_resgid; /* Default gid for reserved blocks */
__u32 s_reserved[235]; /* Padding to the end of the block */
};
#define EXT2_OS_LINUX 0
#define EXT2_OS_HURD 1
#define EXT2_OS_MASIX 2
#define EXT2_CURRENT_REV 0
#define EXT2_DEF_RESUID 0
#define EXT2_DEF_RESGID 0
/*
* Structure of a directory entry
*/
#define EXT2_NAME_LEN 255
struct ext2_dir_entry {
__u32 inode; /* Inode number */
__u16 rec_len; /* Directory entry length */
__u16 name_len; /* Name length */
char name[EXT2_NAME_LEN]; /* File name */
};
/*
* EXT2_DIR_PAD defines the directory entries boundaries
*
* NOTE: It must be a multiple of 4
*/
#define EXT2_DIR_PAD 4
#define EXT2_DIR_ROUND (EXT2_DIR_PAD - 1)
#define EXT2_DIR_REC_LEN(name_len) (((name_len) + 8 + EXT2_DIR_ROUND) & \
~EXT2_DIR_ROUND)
#ifdef __KERNEL__
/*
* Function prototypes
*/
/*
* Ok, these declarations are also in <linux/kernel.h> but none of the
* ext2 source programs needs to include it so they are duplicated here.
*/
#if __GNUC__ < 2 || (__GNUC__ == 2 && __GNUC_MINOR__ < 5)
# define NORET_TYPE __volatile__
# define ATTRIB_NORET /**/
# define NORET_AND /**/
#else
# define NORET_TYPE /**/
# define ATTRIB_NORET __attribute__((noreturn))
# define NORET_AND noreturn,
#endif
/* acl.c */
extern int ext2_permission (struct inode *, int);
/* balloc.c */
extern int ext2_new_block (struct super_block *, unsigned long,
__u32 *, __u32 *);
extern void ext2_free_blocks (struct super_block *, unsigned long,
unsigned long);
extern unsigned long ext2_count_free_blocks (struct super_block *);
extern void ext2_check_blocks_bitmap (struct super_block *);
/* bitmap.c */
extern unsigned long ext2_count_free (char *, unsigned);
/* dir.c */
extern int ext2_check_dir_entry (char *, struct inode *,
struct ext2_dir_entry *, char *,
unsigned long);
/* file.c */
extern int ext2_read (struct inode *, struct file *, char *, int);
extern int ext2_write (struct inode *, struct file *, char *, int);
/* fsync.c */
extern int ext2_sync_file (struct inode *, struct file *);
/* ialloc.c */
extern struct inode * ext2_new_inode (const struct inode *, int);
extern void ext2_free_inode (struct inode *);
extern unsigned long ext2_count_free_inodes (struct super_block *);
extern void ext2_check_inodes_bitmap (struct super_block *);
/* inode.c */
extern int ext2_bmap (struct inode *, int);
extern char * ext2_getblk (struct inode *, long, int, int *);
extern char * ext2_bread (struct inode *, int, int, int *);
extern int ext2_getcluster (struct inode * inode, long block);
extern void ext2_read_inode (struct inode *);
extern void ext2_write_inode (struct inode *);
extern void ext2_put_inode (struct inode *);
extern int ext2_sync_inode (struct inode *);
extern void ext2_discard_prealloc (struct inode *);
/* ioctl.c */
extern int ext2_ioctl (struct inode *, struct file *, unsigned int,
unsigned long);
/* namei.c */
extern void ext2_release (struct inode *, struct file *);
extern int ext2_lookup (struct inode *,const char *, int, struct inode **);
extern int ext2_create (struct inode *,const char *, int, int,
struct inode **);
extern int ext2_mkdir (struct inode *, const char *, int, int);
extern int ext2_rmdir (struct inode *, const char *, int);
extern int ext2_unlink (struct inode *, const char *, int);
extern int ext2_symlink (struct inode *, const char *, int, const char *);
extern int ext2_link (struct inode *, struct inode *, const char *, int);
extern int ext2_mknod (struct inode *, const char *, int, int, int);
extern int ext2_rename (struct inode *, const char *, int,
struct inode *, const char *, int);
/* super.c */
extern void ext2_error (struct super_block *, const char *, const char *, ...)
__attribute__ ((format (printf, 3, 4)));
extern NORET_TYPE void ext2_panic (struct super_block *, const char *,
const char *, ...)
__attribute__ ((NORET_AND format (printf, 3, 4)));
extern void ext2_warning (struct super_block *, const char *, const char *, ...)
__attribute__ ((format (printf, 3, 4)));
extern void ext2_put_super (struct super_block *);
extern void ext2_write_super (struct super_block *);
extern int ext2_remount (struct super_block *, int *, char *);
extern struct super_block * ext2_read_super (struct super_block *,void *,int);
extern void ext2_statfs (struct super_block *, struct statfs *);
/* truncate.c */
extern void ext2_truncate (struct inode *);
/*
* Inodes and files operations
*/
/* dir.c */
extern struct inode_operations ext2_dir_inode_operations;
/* file.c */
extern struct inode_operations ext2_file_inode_operations;
/* symlink.c */
extern struct inode_operations ext2_symlink_inode_operations;
#endif /* __KERNEL__ */
#endif /* _LINUX_EXT2_FS_H */
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