#ifndef __EXT2_FS_H #define __EXT2_FS_H #include #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; uint8_t s_uuid[16]; /* 128-bit uuid for volume */ }; 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 */