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#ifndef __EXT2_FS_H
#define __EXT2_FS_H
#include <stdint.h>
#define EXT2_SUPER_MAGIC 0xEF53
#define EXT2_GOOD_OLD_REV 0 // The good old (original) format
#define EXT2_DYNAMIC_REV 1 // V2 format w/ dynamic inode sizes
#define EXT2_GOOD_OLD_INODE_SIZE 128
// 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
#define EXT3_RESIZE_INO 7 // Reserved group descriptors inode
#define EXT3_JOURNAL_INO 8 // Journal inode
// We're readonly, so we only care about incompat features.
#define EXT2_FEATURE_INCOMPAT_COMPRESSION 0x0001
#define EXT2_FEATURE_INCOMPAT_FILETYPE 0x0002
#define EXT3_FEATURE_INCOMPAT_RECOVER 0x0004
#define EXT3_FEATURE_INCOMPAT_JOURNAL_DEV 0x0008
#define EXT2_FEATURE_INCOMPAT_META_BG 0x0010
#define EXT2_FEATURE_INCOMPAT_ANY 0xffffffff
#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)
/* for EXT4 extent */
#define EXT4_EXT_MAGIC 0xf30a
#define EXT4_EXTENTS_FLAG 0x00080000
/*
* File types and file modes
*/
#define S_IFDIR 0040000 // Directory
#define S_IFCHR 0020000 // Character device
#define S_IFBLK 0060000 // Block device
#define S_IFREG 0100000 // Regular file
#define S_IFIFO 0010000 // FIFO
#define S_IFLNK 0120000 // Symbolic link
#define S_IFSOCK 0140000 // Socket
#define S_IFSHIFT 12
#define T_IFDIR (S_IFDIR >> S_IFSHIFT)
#define T_IFCHR (S_IFCHR >> S_IFSHIFT)
#define T_IFBLK (S_IFBLK >> S_IFSHIFT)
#define T_IFREG (S_IFREG >> S_IFSHIFT)
#define T_IFIFO (S_IFIFO >> S_IFSHIFT)
#define T_IFLNK (S_IFLNK >> S_IFSHIFT)
#define T_IFSOCK (S_IFSOCK >> S_IFSHIFT)
#define ext2_group_desc_lg2size 5
/*
* super block structure:
* include/linux/ext2_fs.h
*/
struct ext2_super_block {
uint32_t s_inodes_count; /* Inodes count */
uint32_t s_blocks_count; /* Blocks count */
uint32_t s_r_blocks_count; /* Reserved blocks count */
uint32_t s_free_blocks_count; /* Free blocks count */
uint32_t s_free_inodes_count; /* Free inodes count */
uint32_t s_first_data_block; /* First Data Block */
uint32_t s_log_block_size; /* Block size */
uint32_t s_log_frag_size; /* Fragment size */
uint32_t s_blocks_per_group; /* # Blocks per group */
uint32_t s_frags_per_group; /* # Fragments per group */
uint32_t s_inodes_per_group; /* # Inodes per group */
uint32_t s_mtime; /* Mount time */
uint32_t s_wtime; /* Write time */
uint16_t s_mnt_count; /* Mount count */
int16_t s_max_mnt_count; /* Maximal mount count */
uint16_t s_magic; /* Magic signature */
uint16_t s_state; /* File system state */
uint16_t s_errors; /* Behaviour when detecting errors */
uint16_t s_minor_rev_level;
uint32_t s_lastcheck; /* time of last check */
uint32_t s_checkinterval; /* max. time between checks */
uint32_t s_creator_os; /* OS */
uint32_t s_rev_level; /* Revision level */
uint16_t s_def_resuid; /* Default uid for reserved blocks */
uint16_t s_def_resgid; /* Default gid for reserved blocks */
uint32_t s_first_ino; /* First non-reserved inode */
uint16_t s_inode_size; /* size of inode structure */
uint16_t s_block_group_nr; /* block group # of this superblock */
uint32_t s_feature_compat; /* compatible feature set */
uint32_t s_feature_incompat; /* incompatible feature set */
uint32_t s_feature_ro_compat; /* readonly-compatible feature set */
uint8_t s_uuid[16]; /* 128-bit uuid for volume */
char s_volume_name[16]; /* volume name */
char s_last_mounted[64]; /* directory where last mounted */
uint32_t s_algorithm_usage_bitmap; /* For compression */
uint8_t s_prealloc_blocks; /* Nr of blocks to try to preallocate*/
uint8_t s_prealloc_dir_blocks;
uint16_t s_reserved_gdt_blocks; /* Per group desc for online growth */
/*
* Journaling support valid if EXT4_FEATURE_COMPAT_HAS_JOURNAL set.
*/
uint8_t s_journal_uuid[16]; /* uuid of journal superblock */
uint32_t s_journal_inum; /* inode number of journal file */
uint32_t s_journal_dev; /* device number of journal file */
uint32_t s_last_orphan; /* start of list of inodes to delete */
uint32_t s_hash_seed[4]; /* HTREE hash seed */
uint8_t s_def_hash_version; /* Default hash version to use */
uint8_t s_reserved_char_pad;
uint16_t s_desc_size; /* size of group descriptor */
uint32_t s_default_mount_opts;
uint32_t s_first_meta_bg; /* First metablock block group */
uint32_t s_mkfs_time; /* When the filesystem was created */
uint32_t s_jnl_blocks[17]; /* Backup of the journal inode */
/* 64bit support valid if EXT4_FEATURE_COMPAT_64BIT */
uint32_t s_blocks_count_hi; /* Blocks count */
uint32_t s_r_blocks_count_hi; /* Reserved blocks count */
uint32_t s_free_blocks_count_hi;/* Free blocks count */
uint16_t s_min_extra_isize; /* All inodes have at least # bytes */
uint16_t s_want_extra_isize; /* New inodes should reserve # bytes */
uint32_t s_flags; /* Miscellaneous flags */
uint16_t s_raid_stride; /* RAID stride */
uint16_t s_mmp_interval; /* # seconds to wait in MMP checking */
uint64_t s_mmp_block; /* Block for multi-mount protection */
uint32_t s_raid_stripe_width; /* blocks on all data disks (N*stride)*/
uint8_t s_log_groups_per_flex; /* FLEX_BG group size */
uint8_t s_reserved_char_pad2;
uint16_t s_reserved_pad;
uint32_t s_reserved[162]; /* Padding to the end of the block */
};
/*******************************************************************************
#ifndef DEPEND
#if ext2_super_block_size != 1024
#error ext2_super_block definition bogus
#endif
#endif
*******************************************************************************/
/*
* ext2 group desc structure:
*/
struct ext2_group_desc {
uint32_t bg_block_bitmap; /* Blocks bitmap block */
uint32_t bg_inode_bitmap; /* Inodes bitmap block */
uint32_t bg_inode_table; /* Inodes table block */
uint16_t bg_free_blocks_count; /* Free blocks count */
uint16_t bg_free_inodes_count; /* Free inodes count */
uint16_t bg_used_dirs_count; /* Directories count */
uint16_t bg_pad;
uint32_t bg_reserved[3];
};
/*******************************************************************************
#ifndef DEPEND
#if ext2_group_desc_size != 32
#error ext2_group_desc definition bogus
#endif
#endif
*******************************************************************************/
/*
* ext2 inode structure:
*/
struct ext2_inode {
uint16_t i_mode; /* File mode */
uint16_t i_uid; /* Owner Uid */
uint32_t i_size; /* 4: Size in bytes */
uint32_t i_atime; /* Access time */
uint32_t i_ctime; /* 12: Creation time */
uint32_t i_mtime; /* Modification time */
uint32_t i_dtime; /* 20: Deletion Time */
uint16_t i_gid; /* Group Id */
uint16_t i_links_count; /* 24: Links count */
uint32_t i_blocks; /* Blocks count */
uint32_t i_flags; /* 32: File flags */
uint32_t l_i_reserved1;
uint32_t i_block[EXT2_N_BLOCKS]; /* 40: Pointers to blocks */
uint32_t i_version; /* File version (for NFS) */
uint32_t i_file_acl; /* File ACL */
uint32_t i_dir_acl; /* Directory ACL */
uint32_t i_faddr; /* Fragment address */
uint8_t l_i_frag; /* Fragment number */
uint8_t l_i_fsize; /* Fragment size */
uint16_t i_pad1;
uint32_t l_i_reserved2[2];
};
/*******************************************************************************
#ifndef DEPEND
#if ext2_inode_size != 128
#error ext2_inode definition bogus
#endif
#endif
*******************************************************************************/
#define EXT2_NAME_LEN 255
struct ext2_dir_entry {
unsigned int d_inode; /* Inode number */
unsigned short d_rec_len; /* Directory entry length */
unsigned char d_name_len; /* Name length */
unsigned char d_file_type;
char d_name[EXT2_NAME_LEN]; /* File name */
};
/*******************************************************************************
#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)
*******************************************************************************/
/*
* This is the extent on-disk structure.
* It's used at the bottom of the tree.
*/
struct ext4_extent {
uint32_t ee_block; /* first logical block extent covers */
uint16_t ee_len; /* number of blocks covered by extent */
uint16_t ee_start_hi; /* high 16 bits of physical block */
uint32_t ee_start_lo; /* low 32 bits of physical block */
};
/*
* This is index on-disk structure.
* It's used at all the levels except the bottom.
*/
struct ext4_extent_idx {
uint32_t ei_block; /* index covers logical blocks from 'block' */
uint32_t ei_leaf_lo; /* pointer to the physical block of the next *
* level. leaf or next index could be there */
uint16_t ei_leaf_hi; /* high 16 bits of physical block */
uint16_t ei_unused;
};
/*
* Each block (leaves and indexes), even inode-stored has header.
*/
struct ext4_extent_header {
uint16_t eh_magic; /* probably will support different formats */
uint16_t eh_entries; /* number of valid entries */
uint16_t eh_max; /* capacity of store in entries */
uint16_t eh_depth; /* has tree real underlying blocks? */
uint32_t eh_generation; /* generation of the tree */
};
#define EXT4_FIRST_EXTENT(header) ( (struct ext4_extent *)(header + 1) )
#define EXT4_FIRST_INDEX(header) ( (struct ext4_extent_idx *) (header + 1) )
/*
* The ext2 super block information in memory
*/
struct ext2_sb_info {
uint32_t s_inodes_per_block;/* Number of inodes per block */
uint32_t s_inodes_per_group;/* Number of inodes in a group */
uint32_t s_blocks_per_group;/* Number of blocks in a group */
uint32_t s_desc_per_block; /* Number of group descriptors per block */
uint32_t s_groups_count; /* Number of groups in the fs */
uint32_t s_first_data_block; /* First Data Block */
int s_inode_size;
};
static inline struct ext2_sb_info *EXT2_SB(struct fs_info *fs)
{
return fs->fs_info;
}
#define EXT2_BLOCKS_PER_GROUP(fs) (EXT2_SB(fs)->s_blocks_per_group)
#define EXT2_INODES_PER_GROUP(fs) (EXT2_SB(fs)->s_inodes_per_group)
#define EXT2_INODES_PER_BLOCK(fs) (EXT2_SB(fs)->s_inodes_per_block)
#define EXT2_DESC_PER_BLOCK(fs) (EXT2_SB(fs)->s_desc_per_block)
/*
* ext2 private inode information
*/
struct ext2_pvt_inode {
union {
uint32_t i_block[EXT2_N_BLOCKS];
struct ext4_extent_header i_extent_hdr;
};
};
#define PVT(i) ((struct ext2_pvt_inode *)((i)->pvt))
/*
* functions
*/
block_t ext2_bmap(struct inode *, block_t, size_t *);
int ext2_next_extent(struct inode *, uint32_t);
#endif /* ext2_fs.h */
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