CloverBootloader/FileSystems/VBoxFsDxe/fsw_ext4_disk.h
2019-09-03 12:58:42 +03:00

501 lines
20 KiB
C

/**
* \file fsw_ext4_disk.h
* ext4 file system on-disk structures.
*/
/*-
* Copyright (c) 2012 Stefan Agner
* Portions Copyright (c) 2006 Christoph Pfisterer
* Portions Copyright (c) 1991-2012 by various Linux kernel contributors
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License
* as published by the Free Software Foundation; either version 2
* of the License, or (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
*/
#ifndef _FSW_EXT4_DISK_H_
#define _FSW_EXT4_DISK_H_
// types
typedef fsw_s8 __s8;
typedef fsw_u8 __u8;
typedef fsw_s16 __s16;
typedef fsw_u16 __u16;
typedef fsw_s32 __s32;
typedef fsw_u32 __u32;
typedef fsw_s64 __s64;
typedef fsw_u64 __u64;
typedef __u16 __le16;
typedef __u32 __le32;
typedef __u64 __le64;
//
// from Linux kernel, fs/ext4/ext4.h
//
/*
* Special inode numbers
*/
#define EXT4_BAD_INO 1 /* Bad blocks inode */
#define EXT4_ROOT_INO 2 /* Root inode */
#define EXT4_USR_QUOTA_INO 3 /* User quota inode */
#define EXT4_GRP_QUOTA_INO 4 /* Group quota inode */
#define EXT4_BOOT_LOADER_INO 5 /* Boot loader inode */
#define EXT4_UNDEL_DIR_INO 6 /* Undelete directory inode */
#define EXT4_RESIZE_INO 7 /* Reserved group descriptors inode */
#define EXT4_JOURNAL_INO 8 /* Journal inode */
/*
* The second extended file system magic number
*/
#define EXT4_SUPER_MAGIC 0xEF53
/*
* Macro-instructions used to manage several block sizes
*/
#define EXT4_MIN_BLOCK_SIZE 1024
#define EXT4_MAX_BLOCK_SIZE 4096
#define EXT4_MIN_BLOCK_LOG_SIZE 10
#define EXT4_BLOCK_SIZE(s) (EXT4_MIN_BLOCK_SIZE << (s)->s_log_block_size)
#define EXT4_ADDR_PER_BLOCK(s) (EXT4_BLOCK_SIZE(s) / sizeof (__u32))
#define EXT4_BLOCK_SIZE_BITS(s) ((s)->s_log_block_size + 10)
#define EXT4_INODE_SIZE(s) (((s)->s_rev_level == EXT4_GOOD_OLD_REV) ? \
EXT4_GOOD_OLD_INODE_SIZE : \
(s)->s_inode_size)
/*
* Structure of a blocks group descriptor
*/
struct ext4_group_desc
{
__le32 bg_block_bitmap_lo; /* Blocks bitmap block */
__le32 bg_inode_bitmap_lo; /* Inodes bitmap block */
__le32 bg_inode_table_lo; /* Inodes table block */
__le16 bg_free_blocks_count_lo;/* Free blocks count */
__le16 bg_free_inodes_count_lo;/* Free inodes count */
__le16 bg_used_dirs_count_lo; /* Directories count */
__le16 bg_flags; /* EXT4_BG_flags (INODE_UNINIT, etc) */
__le32 bg_exclude_bitmap_lo; /* Exclude bitmap for snapshots */
__le16 bg_block_bitmap_csum_lo;/* crc32c(s_uuid+grp_num+bbitmap) LE */
__le16 bg_inode_bitmap_csum_lo;/* crc32c(s_uuid+grp_num+ibitmap) LE */
__le16 bg_itable_unused_lo; /* Unused inodes count */
__le16 bg_checksum; /* crc16(sb_uuid+group+desc) */
__le32 bg_block_bitmap_hi; /* Blocks bitmap block MSB */
__le32 bg_inode_bitmap_hi; /* Inodes bitmap block MSB */
__le32 bg_inode_table_hi; /* Inodes table block MSB */
__le16 bg_free_blocks_count_hi;/* Free blocks count MSB */
__le16 bg_free_inodes_count_hi;/* Free inodes count MSB */
__le16 bg_used_dirs_count_hi; /* Directories count MSB */
__le16 bg_itable_unused_hi; /* Unused inodes count MSB */
__le32 bg_exclude_bitmap_hi; /* Exclude bitmap block MSB */
__le16 bg_block_bitmap_csum_hi;/* crc32c(s_uuid+grp_num+bbitmap) BE */
__le16 bg_inode_bitmap_csum_hi;/* crc32c(s_uuid+grp_num+ibitmap) BE */
__u32 bg_reserved;
};
/*
* Macro-instructions used to manage group descriptors
*/
#define EXT4_MIN_DESC_SIZE 32
#define EXT4_MIN_DESC_SIZE_64BIT 64
#define EXT4_MAX_DESC_SIZE EXT4_MIN_BLOCK_SIZE
#define EXT4_DESC_SIZE(s) ((s)->s_desc_size)
#define EXT4_BLOCKS_PER_GROUP(s) ((s)->s_blocks_per_group)
#define EXT4_DESC_PER_BLOCK(s) (EXT4_BLOCK_SIZE(s) / EXT4_DESC_SIZE(s))
#define EXT4_INODES_PER_GROUP(s) ((s)->s_inodes_per_group)
/*
* Constants relative to the data blocks
*/
#define EXT4_NDIR_BLOCKS 12
#define EXT4_IND_BLOCK EXT4_NDIR_BLOCKS
#define EXT4_DIND_BLOCK (EXT4_IND_BLOCK + 1)
#define EXT4_TIND_BLOCK (EXT4_DIND_BLOCK + 1)
#define EXT4_N_BLOCKS (EXT4_TIND_BLOCK + 1)
/*
* Inode flags
*/
#define EXT4_SECRM_FL 0x00000001 /* Secure deletion */
#define EXT4_UNRM_FL 0x00000002 /* Undelete */
#define EXT4_COMPR_FL 0x00000004 /* Compress file */
#define EXT4_SYNC_FL 0x00000008 /* Synchronous updates */
#define EXT4_IMMUTABLE_FL 0x00000010 /* Immutable file */
#define EXT4_APPEND_FL 0x00000020 /* writes to file may only append */
#define EXT4_NODUMP_FL 0x00000040 /* do not dump file */
#define EXT4_NOATIME_FL 0x00000080 /* do not update atime */
/* Reserved for compression usage... */
#define EXT4_DIRTY_FL 0x00000100
#define EXT4_COMPRBLK_FL 0x00000200 /* One or more compressed clusters */
#define EXT4_NOCOMP_FL 0x00000400 /* Don't compress */
#define EXT4_ECOMPR_FL 0x00000800 /* Compression error */
/* End compression flags --- maybe not all used */
#define EXT4_INDEX_FL 0x00001000 /* hash-indexed directory */
#define EXT4_IMAGIC_FL 0x00002000 /* AFS directory */
#define EXT4_JOURNAL_DATA_FL 0x00004000 /* Reserved for ext3 */
#define EXT4_NOTAIL_FL 0x00008000 /* file tail should not be merged */
#define EXT4_DIRSYNC_FL 0x00010000 /* dirsync behaviour (directories only) */
#define EXT4_TOPDIR_FL 0x00020000 /* Top of directory hierarchies*/
#define EXT4_HUGE_FILE_FL 0x00040000 /* Set to each huge file */
#define EXT4_EXTENTS_FL 0x00080000 /* Inode uses extents */
#define EXT4_EA_INODE_FL 0x00200000 /* Inode used for large EA */
#define EXT4_EOFBLOCKS_FL 0x00400000 /* Blocks allocated beyond EOF */
#define EXT4_RESERVED_FL 0x80000000 /* reserved for ext4 lib */
#define EXT4_FL_USER_VISIBLE 0x004BDFFF /* User visible flags */
#define EXT4_FL_USER_MODIFIABLE 0x004B80FF /* User modifiable flags */
/*
* Structure of an inode on the disk
*/
struct ext4_inode {
__le16 i_mode; /* File mode */
__le16 i_uid; /* Low 16 bits of Owner Uid */
__le32 i_size_lo; /* Size in bytes */
__le32 i_atime; /* Access time */
__le32 i_ctime; /* Inode Change time */
__le32 i_mtime; /* Modification time */
__le32 i_dtime; /* Deletion Time */
__le16 i_gid; /* Low 16 bits of Group Id */
__le16 i_links_count; /* Links count */
__le32 i_blocks_lo; /* Blocks count */
__le32 i_flags; /* File flags */
union {
struct {
__le32 l_i_version;
} linux1;
struct {
__u32 h_i_translator;
} hurd1;
struct {
__u32 m_i_reserved1;
} masix1;
} osd1; /* OS dependent 1 */
__le32 i_block[EXT4_N_BLOCKS];/* Pointers to blocks */
__le32 i_generation; /* File version (for NFS) */
__le32 i_file_acl_lo; /* File ACL */
__le32 i_size_high;
__le32 i_obso_faddr; /* Obsoleted fragment address */
union {
struct {
__le16 l_i_blocks_high; /* were l_i_reserved1 */
__le16 l_i_file_acl_high;
__le16 l_i_uid_high; /* these 2 fields */
__le16 l_i_gid_high; /* were reserved2[0] */
__le16 l_i_checksum_lo;/* crc32c(uuid+inum+inode) LE */
__le16 l_i_reserved;
} linux2;
struct {
__le16 h_i_reserved1; /* Obsoleted fragment number/size which are removed in ext4 */
__u16 h_i_mode_high;
__u16 h_i_uid_high;
__u16 h_i_gid_high;
__u32 h_i_author;
} hurd2;
struct {
__le16 h_i_reserved1; /* Obsoleted fragment number/size which are removed in ext4 */
__le16 m_i_file_acl_high;
__u32 m_i_reserved2[2];
} masix2;
} osd2; /* OS dependent 2 */
__le16 i_extra_isize;
__le16 i_checksum_hi; /* crc32c(uuid+inum+inode) BE */
__le32 i_ctime_extra; /* extra Change time (nsec << 2 | epoch) */
__le32 i_mtime_extra; /* extra Modification time(nsec << 2 | epoch) */
__le32 i_atime_extra; /* extra Access time (nsec << 2 | epoch) */
__le32 i_crtime; /* File Creation time */
__le32 i_crtime_extra; /* extra FileCreationtime (nsec << 2 | epoch) */
__le32 i_version_hi; /* high 32 bits for 64-bit version */
};
/*
* Inode flags used for atomic set/get
*/
enum {
EXT4_INODE_SECRM = 0, /* Secure deletion */
EXT4_INODE_UNRM = 1, /* Undelete */
EXT4_INODE_COMPR = 2, /* Compress file */
EXT4_INODE_SYNC = 3, /* Synchronous updates */
EXT4_INODE_IMMUTABLE = 4, /* Immutable file */
EXT4_INODE_APPEND = 5, /* writes to file may only append */
EXT4_INODE_NODUMP = 6, /* do not dump file */
EXT4_INODE_NOATIME = 7, /* do not update atime */
/* Reserved for compression usage... */
EXT4_INODE_DIRTY = 8,
EXT4_INODE_COMPRBLK = 9, /* One or more compressed clusters */
EXT4_INODE_NOCOMPR = 10, /* Don't compress */
EXT4_INODE_ECOMPR = 11, /* Compression error */
/* End compression flags --- maybe not all used */
EXT4_INODE_INDEX = 12, /* hash-indexed directory */
EXT4_INODE_IMAGIC = 13, /* AFS directory */
EXT4_INODE_JOURNAL_DATA = 14, /* file data should be journaled */
EXT4_INODE_NOTAIL = 15, /* file tail should not be merged */
EXT4_INODE_DIRSYNC = 16, /* dirsync behaviour (directories only) */
EXT4_INODE_TOPDIR = 17, /* Top of directory hierarchies*/
EXT4_INODE_HUGE_FILE = 18, /* Set to each huge file */
EXT4_INODE_EXTENTS = 19, /* Inode uses extents */
EXT4_INODE_EA_INODE = 21, /* Inode used for large EA */
EXT4_INODE_EOFBLOCKS = 22, /* Blocks allocated beyond EOF */
EXT4_INODE_RESERVED = 31, /* reserved for ext4 lib */
};
/*
* Structure of the super block
*/
struct ext4_super_block {
/*00*/ __le32 s_inodes_count; /* Inodes count */
__le32 s_blocks_count_lo; /* Blocks count */
__le32 s_r_blocks_count_lo; /* Reserved blocks count */
__le32 s_free_blocks_count_lo; /* Free blocks count */
/*10*/ __le32 s_free_inodes_count; /* Free inodes count */
__le32 s_first_data_block; /* First Data Block */
__le32 s_log_block_size; /* Block size */
__le32 s_log_cluster_size; /* Allocation cluster size */
/*20*/ __le32 s_blocks_per_group; /* # Blocks per group */
__le32 s_clusters_per_group; /* # Clusters per group */
__le32 s_inodes_per_group; /* # Inodes per group */
__le32 s_mtime; /* Mount time */
/*30*/ __le32 s_wtime; /* Write time */
__le16 s_mnt_count; /* Mount count */
__le16 s_max_mnt_count; /* Maximal mount count */
__le16 s_magic; /* Magic signature */
__le16 s_state; /* File system state */
__le16 s_errors; /* Behaviour when detecting errors */
__le16 s_minor_rev_level; /* minor revision level */
/*40*/ __le32 s_lastcheck; /* time of last check */
__le32 s_checkinterval; /* max. time between checks */
__le32 s_creator_os; /* OS */
__le32 s_rev_level; /* Revision level */
/*50*/ __le16 s_def_resuid; /* Default uid for reserved blocks */
__le16 s_def_resgid; /* Default gid for reserved blocks */
/*
* These fields are for EXT4_DYNAMIC_REV superblocks only.
*
* Note: the difference between the compatible feature set and
* the incompatible feature set is that if there is a bit set
* in the incompatible feature set that the kernel doesn't
* know about, it should refuse to mount the filesystem.
*
* e2fsck's requirements are more strict; if it doesn't know
* about a feature in either the compatible or incompatible
* feature set, it must abort and not try to meddle with
* things it doesn't understand...
*/
__le32 s_first_ino; /* First non-reserved inode */
__le16 s_inode_size; /* size of inode structure */
__le16 s_block_group_nr; /* block group # of this superblock */
__le32 s_feature_compat; /* compatible feature set */
/*60*/ __le32 s_feature_incompat; /* incompatible feature set */
__le32 s_feature_ro_compat; /* readonly-compatible feature set */
/*68*/ __u8 s_uuid[16]; /* 128-bit uuid for volume */
/*78*/ char s_volume_name[16]; /* volume name */
/*88*/ char s_last_mounted[64]; /* directory where last mounted */
/*C8*/ __le32 s_algorithm_usage_bitmap; /* For compression */
/*
* Performance hints. Directory preallocation should only
* happen if the EXT4_FEATURE_COMPAT_DIR_PREALLOC flag is on.
*/
__u8 s_prealloc_blocks; /* Nr of blocks to try to preallocate*/
__u8 s_prealloc_dir_blocks; /* Nr to preallocate for dirs */
__le16 s_reserved_gdt_blocks; /* Per group desc for online growth */
/*
* Journaling support valid if EXT4_FEATURE_COMPAT_HAS_JOURNAL set.
*/
/*D0*/ __u8 s_journal_uuid[16]; /* uuid of journal superblock */
/*E0*/ __le32 s_journal_inum; /* inode number of journal file */
__le32 s_journal_dev; /* device number of journal file */
__le32 s_last_orphan; /* start of list of inodes to delete */
__le32 s_hash_seed[4]; /* HTREE hash seed */
__u8 s_def_hash_version; /* Default hash version to use */
__u8 s_jnl_backup_type;
__le16 s_desc_size; /* size of group descriptor */
/*100*/ __le32 s_default_mount_opts;
__le32 s_first_meta_bg; /* First metablock block group */
__le32 s_mkfs_time; /* When the filesystem was created */
__le32 s_jnl_blocks[17]; /* Backup of the journal inode */
/* 64bit support valid if EXT4_FEATURE_COMPAT_64BIT */
/*150*/ __le32 s_blocks_count_hi; /* Blocks count */
__le32 s_r_blocks_count_hi; /* Reserved blocks count */
__le32 s_free_blocks_count_hi; /* Free blocks count */
__le16 s_min_extra_isize; /* All inodes have at least # bytes */
__le16 s_want_extra_isize; /* New inodes should reserve # bytes */
__le32 s_flags; /* Miscellaneous flags */
__le16 s_raid_stride; /* RAID stride */
__le16 s_mmp_update_interval; /* # seconds to wait in MMP checking */
__le64 s_mmp_block; /* Block for multi-mount protection */
__le32 s_raid_stripe_width; /* blocks on all data disks (N*stride)*/
__u8 s_log_groups_per_flex; /* FLEX_BG group size */
__u8 s_checksum_type; /* metadata checksum algorithm used */
__le16 s_reserved_pad;
__le64 s_kbytes_written; /* nr of lifetime kilobytes written */
__le32 s_snapshot_inum; /* Inode number of active snapshot */
__le32 s_snapshot_id; /* sequential ID of active snapshot */
__le64 s_snapshot_r_blocks_count; /* reserved blocks for active
snapshot's future use */
__le32 s_snapshot_list; /* inode number of the head of the
on-disk snapshot list */
#define EXT4_S_ERR_START offsetof(struct ext4_super_block, s_error_count)
__le32 s_error_count; /* number of fs errors */
__le32 s_first_error_time; /* first time an error happened */
__le32 s_first_error_ino; /* inode involved in first error */
__le64 s_first_error_block; /* block involved of first error */
__u8 s_first_error_func[32]; /* function where the error happened */
__le32 s_first_error_line; /* line number where error happened */
__le32 s_last_error_time; /* most recent time of an error */
__le32 s_last_error_ino; /* inode involved in last error */
__le32 s_last_error_line; /* line number where error happened */
__le64 s_last_error_block; /* block involved of last error */
__u8 s_last_error_func[32]; /* function where the error happened */
#define EXT4_S_ERR_END offsetof(struct ext4_super_block, s_mount_opts)
__u8 s_mount_opts[64];
__le32 s_usr_quota_inum; /* inode for tracking user quota */
__le32 s_grp_quota_inum; /* inode for tracking group quota */
__le32 s_overhead_clusters; /* overhead blocks/clusters in fs */
__le32 s_reserved[108]; /* Padding to the end of the block */
__le32 s_checksum; /* crc32c(superblock) */
};
/*
* Revision levels
*/
#define EXT4_GOOD_OLD_REV 0 /* The good old (original) format */
#define EXT4_DYNAMIC_REV 1 /* V2 format w/ dynamic inode sizes */
#define EXT4_CURRENT_REV EXT4_GOOD_OLD_REV
#define EXT4_MAX_SUPP_REV EXT4_DYNAMIC_REV
#define EXT4_GOOD_OLD_INODE_SIZE 128
/*
* Feature set definitions (only the once we need for read support)
*/
#define EXT4_FEATURE_RO_COMPAT_SPARSE_SUPER 0x0001
#define EXT4_FEATURE_INCOMPAT_COMPRESSION 0x0001
#define EXT4_FEATURE_INCOMPAT_FILETYPE 0x0002
#define EXT4_FEATURE_INCOMPAT_RECOVER 0x0004 /* Needs recovery */
#define EXT4_FEATURE_INCOMPAT_JOURNAL_DEV 0x0008 /* Journal device */
#define EXT4_FEATURE_INCOMPAT_META_BG 0x0010
#define EXT4_FEATURE_INCOMPAT_EXTENTS 0x0040 /* extents support */
#define EXT4_FEATURE_INCOMPAT_64BIT 0x0080
#define EXT4_FEATURE_INCOMPAT_MMP 0x0100
#define EXT4_FEATURE_INCOMPAT_FLEX_BG 0x0200
#define EXT4_FEATURE_INCOMPAT_EA_INODE 0x0400 /* EA in inode */
#define EXT4_FEATURE_INCOMPAT_DIRDATA 0x1000 /* data in dirent */
#define EXT4_FEATURE_INCOMPAT_BG_USE_META_CSUM 0x2000 /* use crc32c for bg */
#define EXT4_FEATURE_INCOMPAT_LARGEDIR 0x4000 /* >2GB or 3-lvl htree */
#define EXT4_FEATURE_INCOMPAT_INLINEDATA 0x8000 /* data in inode */
#define EXT4_FEATURE_INCOMPAT_SUPP (EXT4_FEATURE_INCOMPAT_FILETYPE| \
EXT4_FEATURE_INCOMPAT_RECOVER| \
EXT4_FEATURE_INCOMPAT_META_BG| \
EXT4_FEATURE_INCOMPAT_EXTENTS| \
EXT4_FEATURE_INCOMPAT_64BIT| \
EXT4_FEATURE_INCOMPAT_FLEX_BG| \
EXT4_FEATURE_INCOMPAT_MMP)
/*
* Structure of a directory entry
*/
#define EXT4_NAME_LEN 255
struct ext4_dir_entry {
__le32 inode; /* Inode number */
__le16 rec_len; /* Directory entry length */
__u8 name_len; /* Name length */
__u8 file_type;
char name[EXT4_NAME_LEN]; /* File name */
};
// NOTE: The original Linux kernel header defines ext4_dir_entry with the original
// layout and ext4_dir_entry_2 with the revised layout. We simply use the revised one.
/*
* Ext2 directory file types. Only the low 3 bits are used. The
* other bits are reserved for now.
*/
enum {
EXT4_FT_UNKNOWN,
EXT4_FT_REG_FILE,
EXT4_FT_DIR,
EXT4_FT_CHRDEV,
EXT4_FT_BLKDEV,
EXT4_FT_FIFO,
EXT4_FT_SOCK,
EXT4_FT_SYMLINK,
EXT4_FT_MAX
};
/*
* ext4_inode has i_block array (60 bytes total).
* The first 12 bytes store ext4_extent_header;
* the remainder stores an array of ext4_extent.
* For non-inode extent blocks, ext4_extent_tail
* follows the array.
*/
/*
* This is the extent tail on-disk structure.
* All other extent structures are 12 bytes long. It turns out that
* block_size % 12 >= 4 for at least all powers of 2 greater than 512, which
* covers all valid ext4 block sizes. Therefore, this tail structure can be
* crammed into the end of the block without having to rebalance the tree.
*/
struct ext4_extent_tail {
__le32 et_checksum; /* crc32c(uuid+inum+extent_block) */
};
/*
* This is the extent on-disk structure.
* It's used at the bottom of the tree.
*/
struct ext4_extent {
__le32 ee_block; /* first logical block extent covers */
__le16 ee_len; /* number of blocks covered by extent */
__le16 ee_start_hi; /* high 16 bits of physical block */
__le32 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 {
__le32 ei_block; /* index covers logical blocks from 'block' */
__le32 ei_leaf_lo; /* pointer to the physical block of the next *
* level. leaf or next index could be there */
__le16 ei_leaf_hi; /* high 16 bits of physical block */
__u16 ei_unused;
};
/*
* Each block (leaves and indexes), even inode-stored has header.
*/
struct ext4_extent_header {
__le16 eh_magic; /* probably will support different formats */
__le16 eh_entries; /* number of valid entries */
__le16 eh_max; /* capacity of store in entries */
__le16 eh_depth; /* has tree real underlying blocks? */
__le32 eh_generation; /* generation of the tree */
};
#define EXT4_EXT_MAGIC (0xf30a)
#endif