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ext4.h
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/*
* ext4.h
*
* Copyright (C) 1992, 1993, 1994, 1995
* Remy Card ([email protected])
* 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 _EXT4_H
#define _EXT4_H
#include <linux/types.h>
#include <linux/blkdev.h>
#include <linux/magic.h>
#include <linux/jbd2.h>
#include <linux/quota.h>
#include <linux/rwsem.h>
#include <linux/rbtree.h>
#include <linux/seqlock.h>
#include <linux/mutex.h>
#include <linux/timer.h>
#include <linux/version.h>
#include <linux/wait.h>
#include <linux/blockgroup_lock.h>
#include <linux/percpu_counter.h>
#include <linux/ratelimit.h>
#include <crypto/hash.h>
#include <linux/falloc.h>
#ifdef __KERNEL__
#include <linux/compat.h>
#endif
/*
* The fourth extended filesystem constants/structures
*/
/*
* with AGGRESSIVE_CHECK allocator runs consistency checks over
* structures. these checks slow things down a lot
*/
#define AGGRESSIVE_CHECK__
/*
* with DOUBLE_CHECK defined mballoc creates persistent in-core
* bitmaps, maintains and uses them to check for double allocations
*/
#define DOUBLE_CHECK__
/*
* Define EXT4FS_DEBUG to produce debug messages
*/
#undef EXT4FS_DEBUG
/*
* Debug code
*/
#ifdef EXT4FS_DEBUG
#define ext4_debug(f, a...) \
do { \
printk(KERN_DEBUG "EXT4-fs DEBUG (%s, %d): %s:", \
__FILE__, __LINE__, __func__); \
printk(KERN_DEBUG f, ## a); \
} while (0)
#else
#define ext4_debug(fmt, ...) no_printk(fmt, ##__VA_ARGS__)
#endif
/*
* Turn on EXT_DEBUG to get lots of info about extents operations.
*/
#define EXT_DEBUG__
#ifdef EXT_DEBUG
#define ext_debug(fmt, ...) printk(fmt, ##__VA_ARGS__)
#else
#define ext_debug(fmt, ...) no_printk(fmt, ##__VA_ARGS__)
#endif
/* data type for block offset of block group */
typedef int ext4_grpblk_t;
/* data type for filesystem-wide blocks number */
typedef unsigned long long ext4_fsblk_t;
/* data type for file logical block number */
typedef __u32 ext4_lblk_t;
/* data type for block group number */
typedef unsigned int ext4_group_t;
enum SHIFT_DIRECTION {
SHIFT_LEFT = 0,
SHIFT_RIGHT,
};
/*
* Flags used in mballoc's allocation_context flags field.
*
* Also used to show what's going on for debugging purposes when the
* flag field is exported via the traceport interface
*/
/* prefer goal again. length */
#define EXT4_MB_HINT_MERGE 0x0001
/* blocks already reserved */
#define EXT4_MB_HINT_RESERVED 0x0002
/* metadata is being allocated */
#define EXT4_MB_HINT_METADATA 0x0004
/* first blocks in the file */
#define EXT4_MB_HINT_FIRST 0x0008
/* search for the best chunk */
#define EXT4_MB_HINT_BEST 0x0010
/* data is being allocated */
#define EXT4_MB_HINT_DATA 0x0020
/* don't preallocate (for tails) */
#define EXT4_MB_HINT_NOPREALLOC 0x0040
/* allocate for locality group */
#define EXT4_MB_HINT_GROUP_ALLOC 0x0080
/* allocate goal blocks or none */
#define EXT4_MB_HINT_GOAL_ONLY 0x0100
/* goal is meaningful */
#define EXT4_MB_HINT_TRY_GOAL 0x0200
/* blocks already pre-reserved by delayed allocation */
#define EXT4_MB_DELALLOC_RESERVED 0x0400
/* We are doing stream allocation */
#define EXT4_MB_STREAM_ALLOC 0x0800
/* Use reserved root blocks if needed */
#define EXT4_MB_USE_ROOT_BLOCKS 0x1000
/* Use blocks from reserved pool */
#define EXT4_MB_USE_RESERVED 0x2000
struct ext4_allocation_request {
/* target inode for block we're allocating */
struct inode *inode;
/* how many blocks we want to allocate */
unsigned int len;
/* logical block in target inode */
ext4_lblk_t logical;
/* the closest logical allocated block to the left */
ext4_lblk_t lleft;
/* the closest logical allocated block to the right */
ext4_lblk_t lright;
/* phys. target (a hint) */
ext4_fsblk_t goal;
/* phys. block for the closest logical allocated block to the left */
ext4_fsblk_t pleft;
/* phys. block for the closest logical allocated block to the right */
ext4_fsblk_t pright;
/* flags. see above EXT4_MB_HINT_* */
unsigned int flags;
};
/*
* Logical to physical block mapping, used by ext4_map_blocks()
*
* This structure is used to pass requests into ext4_map_blocks() as
* well as to store the information returned by ext4_map_blocks(). It
* takes less room on the stack than a struct buffer_head.
*/
#define EXT4_MAP_NEW (1 << BH_New)
#define EXT4_MAP_MAPPED (1 << BH_Mapped)
#define EXT4_MAP_UNWRITTEN (1 << BH_Unwritten)
#define EXT4_MAP_BOUNDARY (1 << BH_Boundary)
#define EXT4_MAP_FLAGS (EXT4_MAP_NEW | EXT4_MAP_MAPPED |\
EXT4_MAP_UNWRITTEN | EXT4_MAP_BOUNDARY)
struct ext4_map_blocks {
ext4_fsblk_t m_pblk;
ext4_lblk_t m_lblk;
unsigned int m_len;
unsigned int m_flags;
};
/*
* Flags for ext4_io_end->flags
*/
#define EXT4_IO_END_UNWRITTEN 0x0001
/*
* For converting unwritten extents on a work queue. 'handle' is used for
* buffered writeback.
*/
typedef struct ext4_io_end {
struct list_head list; /* per-file finished IO list */
handle_t *handle; /* handle reserved for extent
* conversion */
struct inode *inode; /* file being written to */
struct bio *bio; /* Linked list of completed
* bios covering the extent */
unsigned int flag; /* unwritten or not */
atomic_t count; /* reference counter */
loff_t offset; /* offset in the file */
ssize_t size; /* size of the extent */
} ext4_io_end_t;
struct ext4_io_submit {
struct writeback_control *io_wbc;
struct bio *io_bio;
ext4_io_end_t *io_end;
sector_t io_next_block;
};
/*
* Special inodes 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 */
/* First non-reserved inode for old ext4 filesystems */
#define EXT4_GOOD_OLD_FIRST_INO 11
/*
* Maximal count of links to a file
*/
#define EXT4_LINK_MAX 65000
/*
* Macro-instructions used to manage several block sizes
*/
#define EXT4_MIN_BLOCK_SIZE 1024
#define EXT4_MAX_BLOCK_SIZE 65536
#define EXT4_MIN_BLOCK_LOG_SIZE 10
#define EXT4_MAX_BLOCK_LOG_SIZE 16
#ifdef __KERNEL__
# define EXT4_BLOCK_SIZE(s) ((s)->s_blocksize)
#else
# define EXT4_BLOCK_SIZE(s) (EXT4_MIN_BLOCK_SIZE << (s)->s_log_block_size)
#endif
#define EXT4_ADDR_PER_BLOCK(s) (EXT4_BLOCK_SIZE(s) / sizeof(__u32))
#define EXT4_CLUSTER_SIZE(s) (EXT4_BLOCK_SIZE(s) << \
EXT4_SB(s)->s_cluster_bits)
#ifdef __KERNEL__
# define EXT4_BLOCK_SIZE_BITS(s) ((s)->s_blocksize_bits)
# define EXT4_CLUSTER_BITS(s) (EXT4_SB(s)->s_cluster_bits)
#else
# define EXT4_BLOCK_SIZE_BITS(s) ((s)->s_log_block_size + 10)
#endif
#ifdef __KERNEL__
#define EXT4_ADDR_PER_BLOCK_BITS(s) (EXT4_SB(s)->s_addr_per_block_bits)
#define EXT4_INODE_SIZE(s) (EXT4_SB(s)->s_inode_size)
#define EXT4_FIRST_INO(s) (EXT4_SB(s)->s_first_ino)
#else
#define EXT4_INODE_SIZE(s) (((s)->s_rev_level == EXT4_GOOD_OLD_REV) ? \
EXT4_GOOD_OLD_INODE_SIZE : \
(s)->s_inode_size)
#define EXT4_FIRST_INO(s) (((s)->s_rev_level == EXT4_GOOD_OLD_REV) ? \
EXT4_GOOD_OLD_FIRST_INO : \
(s)->s_first_ino)
#endif
#define EXT4_BLOCK_ALIGN(size, blkbits) ALIGN((size), (1 << (blkbits)))
/* Translate a block number to a cluster number */
#define EXT4_B2C(sbi, blk) ((blk) >> (sbi)->s_cluster_bits)
/* Translate a cluster number to a block number */
#define EXT4_C2B(sbi, cluster) ((cluster) << (sbi)->s_cluster_bits)
/* Translate # of blks to # of clusters */
#define EXT4_NUM_B2C(sbi, blks) (((blks) + (sbi)->s_cluster_ratio - 1) >> \
(sbi)->s_cluster_bits)
/* Mask out the low bits to get the starting block of the cluster */
#define EXT4_PBLK_CMASK(s, pblk) ((pblk) & \
~((ext4_fsblk_t) (s)->s_cluster_ratio - 1))
#define EXT4_LBLK_CMASK(s, lblk) ((lblk) & \
~((ext4_lblk_t) (s)->s_cluster_ratio - 1))
/* Get the cluster offset */
#define EXT4_PBLK_COFF(s, pblk) ((pblk) & \
((ext4_fsblk_t) (s)->s_cluster_ratio - 1))
#define EXT4_LBLK_COFF(s, lblk) ((lblk) & \
((ext4_lblk_t) (s)->s_cluster_ratio - 1))
/*
* 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;
};
#define EXT4_BG_INODE_BITMAP_CSUM_HI_END \
(offsetof(struct ext4_group_desc, bg_inode_bitmap_csum_hi) + \
sizeof(__le16))
#define EXT4_BG_BLOCK_BITMAP_CSUM_HI_END \
(offsetof(struct ext4_group_desc, bg_block_bitmap_csum_hi) + \
sizeof(__le16))
/*
* Structure of a flex block group info
*/
struct flex_groups {
atomic64_t free_clusters;
atomic_t free_inodes;
atomic_t used_dirs;
};
#define EXT4_BG_INODE_UNINIT 0x0001 /* Inode table/bitmap not in use */
#define EXT4_BG_BLOCK_UNINIT 0x0002 /* Block bitmap not in use */
#define EXT4_BG_INODE_ZEROED 0x0004 /* On-disk itable initialized to zero */
/*
* 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) (EXT4_SB(s)->s_desc_size)
#ifdef __KERNEL__
# define EXT4_BLOCKS_PER_GROUP(s) (EXT4_SB(s)->s_blocks_per_group)
# define EXT4_CLUSTERS_PER_GROUP(s) (EXT4_SB(s)->s_clusters_per_group)
# define EXT4_DESC_PER_BLOCK(s) (EXT4_SB(s)->s_desc_per_block)
# define EXT4_INODES_PER_GROUP(s) (EXT4_SB(s)->s_inodes_per_group)
# define EXT4_DESC_PER_BLOCK_BITS(s) (EXT4_SB(s)->s_desc_per_block_bits)
#else
# 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)
#endif
/*
* 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_NOCOMPR_FL 0x00000400 /* Don't compress */
/* nb: was previously EXT2_ECOMPR_FL */
#define EXT4_ENCRYPT_FL 0x00000800 /* encrypted file */
/* 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 /* file data should be journaled */
#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_INLINE_DATA_FL 0x10000000 /* Inode has inline data. */
#define EXT4_PROJINHERIT_FL 0x20000000 /* Create with parents projid */
#define EXT4_RESERVED_FL 0x80000000 /* reserved for ext4 lib */
#define EXT4_FL_USER_VISIBLE 0x304BDFFF /* User visible flags */
#define EXT4_FL_USER_MODIFIABLE 0x204380FF /* User modifiable flags */
#define EXT4_FL_XFLAG_VISIBLE (EXT4_SYNC_FL | \
EXT4_IMMUTABLE_FL | \
EXT4_APPEND_FL | \
EXT4_NODUMP_FL | \
EXT4_NOATIME_FL | \
EXT4_PROJINHERIT_FL)
/* Flags that should be inherited by new inodes from their parent. */
#define EXT4_FL_INHERITED (EXT4_SECRM_FL | EXT4_UNRM_FL | EXT4_COMPR_FL |\
EXT4_SYNC_FL | EXT4_NODUMP_FL | EXT4_NOATIME_FL |\
EXT4_NOCOMPR_FL | EXT4_JOURNAL_DATA_FL |\
EXT4_NOTAIL_FL | EXT4_DIRSYNC_FL |\
EXT4_PROJINHERIT_FL)
/* Flags that are appropriate for regular files (all but dir-specific ones). */
#define EXT4_REG_FLMASK (~(EXT4_DIRSYNC_FL | EXT4_TOPDIR_FL))
/* Flags that are appropriate for non-directories/regular files. */
#define EXT4_OTHER_FLMASK (EXT4_NODUMP_FL | EXT4_NOATIME_FL)
/* Mask out flags that are inappropriate for the given type of inode. */
static inline __u32 ext4_mask_flags(umode_t mode, __u32 flags)
{
if (S_ISDIR(mode))
return flags;
else if (S_ISREG(mode))
return flags & EXT4_REG_FLMASK;
else
return flags & EXT4_OTHER_FLMASK;
}
/*
* 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_ENCRYPT = 11, /* Encrypted file */
/* 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_INLINE_DATA = 28, /* Data in inode. */
EXT4_INODE_PROJINHERIT = 29, /* Create with parents projid */
EXT4_INODE_RESERVED = 31, /* reserved for ext4 lib */
};
/*
* Since it's pretty easy to mix up bit numbers and hex values, we use a
* build-time check to make sure that EXT4_XXX_FL is consistent with respect to
* EXT4_INODE_XXX. If all is well, the macros will be dropped, so, it won't cost
* any extra space in the compiled kernel image, otherwise, the build will fail.
* It's important that these values are the same, since we are using
* EXT4_INODE_XXX to test for flag values, but EXT4_XXX_FL must be consistent
* with the values of FS_XXX_FL defined in include/linux/fs.h and the on-disk
* values found in ext2, ext3 and ext4 filesystems, and of course the values
* defined in e2fsprogs.
*
* It's not paranoia if the Murphy's Law really *is* out to get you. :-)
*/
#define TEST_FLAG_VALUE(FLAG) (EXT4_##FLAG##_FL == (1 << EXT4_INODE_##FLAG))
#define CHECK_FLAG_VALUE(FLAG) BUILD_BUG_ON(!TEST_FLAG_VALUE(FLAG))
static inline void ext4_check_flag_values(void)
{
CHECK_FLAG_VALUE(SECRM);
CHECK_FLAG_VALUE(UNRM);
CHECK_FLAG_VALUE(COMPR);
CHECK_FLAG_VALUE(SYNC);
CHECK_FLAG_VALUE(IMMUTABLE);
CHECK_FLAG_VALUE(APPEND);
CHECK_FLAG_VALUE(NODUMP);
CHECK_FLAG_VALUE(NOATIME);
CHECK_FLAG_VALUE(DIRTY);
CHECK_FLAG_VALUE(COMPRBLK);
CHECK_FLAG_VALUE(NOCOMPR);
CHECK_FLAG_VALUE(ENCRYPT);
CHECK_FLAG_VALUE(INDEX);
CHECK_FLAG_VALUE(IMAGIC);
CHECK_FLAG_VALUE(JOURNAL_DATA);
CHECK_FLAG_VALUE(NOTAIL);
CHECK_FLAG_VALUE(DIRSYNC);
CHECK_FLAG_VALUE(TOPDIR);
CHECK_FLAG_VALUE(HUGE_FILE);
CHECK_FLAG_VALUE(EXTENTS);
CHECK_FLAG_VALUE(EA_INODE);
CHECK_FLAG_VALUE(EOFBLOCKS);
CHECK_FLAG_VALUE(INLINE_DATA);
CHECK_FLAG_VALUE(PROJINHERIT);
CHECK_FLAG_VALUE(RESERVED);
}
/* Used to pass group descriptor data when online resize is done */
struct ext4_new_group_input {
__u32 group; /* Group number for this data */
__u64 block_bitmap; /* Absolute block number of block bitmap */
__u64 inode_bitmap; /* Absolute block number of inode bitmap */
__u64 inode_table; /* Absolute block number of inode table start */
__u32 blocks_count; /* Total number of blocks in this group */
__u16 reserved_blocks; /* Number of reserved blocks in this group */
__u16 unused;
};
#if defined(__KERNEL__) && defined(CONFIG_COMPAT)
struct compat_ext4_new_group_input {
u32 group;
compat_u64 block_bitmap;
compat_u64 inode_bitmap;
compat_u64 inode_table;
u32 blocks_count;
u16 reserved_blocks;
u16 unused;
};
#endif
/* The struct ext4_new_group_input in kernel space, with free_blocks_count */
struct ext4_new_group_data {
__u32 group;
__u64 block_bitmap;
__u64 inode_bitmap;
__u64 inode_table;
__u32 blocks_count;
__u16 reserved_blocks;
__u16 unused;
__u32 free_blocks_count;
};
/* Indexes used to index group tables in ext4_new_group_data */
enum {
BLOCK_BITMAP = 0, /* block bitmap */
INODE_BITMAP, /* inode bitmap */
INODE_TABLE, /* inode tables */
GROUP_TABLE_COUNT,
};
/*
* Flags used by ext4_map_blocks()
*/
/* Allocate any needed blocks and/or convert an unwritten
extent to be an initialized ext4 */
#define EXT4_GET_BLOCKS_CREATE 0x0001
/* Request the creation of an unwritten extent */
#define EXT4_GET_BLOCKS_UNWRIT_EXT 0x0002
#define EXT4_GET_BLOCKS_CREATE_UNWRIT_EXT (EXT4_GET_BLOCKS_UNWRIT_EXT|\
EXT4_GET_BLOCKS_CREATE)
/* Caller is from the delayed allocation writeout path
* finally doing the actual allocation of delayed blocks */
#define EXT4_GET_BLOCKS_DELALLOC_RESERVE 0x0004
/* caller is from the direct IO path, request to creation of an
unwritten extents if not allocated, split the unwritten
extent if blocks has been preallocated already*/
#define EXT4_GET_BLOCKS_PRE_IO 0x0008
#define EXT4_GET_BLOCKS_CONVERT 0x0010
#define EXT4_GET_BLOCKS_IO_CREATE_EXT (EXT4_GET_BLOCKS_PRE_IO|\
EXT4_GET_BLOCKS_CREATE_UNWRIT_EXT)
/* Convert extent to initialized after IO complete */
#define EXT4_GET_BLOCKS_IO_CONVERT_EXT (EXT4_GET_BLOCKS_CONVERT|\
EXT4_GET_BLOCKS_CREATE_UNWRIT_EXT)
/* Eventual metadata allocation (due to growing extent tree)
* should not fail, so try to use reserved blocks for that.*/
#define EXT4_GET_BLOCKS_METADATA_NOFAIL 0x0020
/* Don't normalize allocation size (used for fallocate) */
#define EXT4_GET_BLOCKS_NO_NORMALIZE 0x0040
/* Request will not result in inode size update (user for fallocate) */
#define EXT4_GET_BLOCKS_KEEP_SIZE 0x0080
/* Convert written extents to unwritten */
#define EXT4_GET_BLOCKS_CONVERT_UNWRITTEN 0x0100
/* Write zeros to newly created written extents */
#define EXT4_GET_BLOCKS_ZERO 0x0200
#define EXT4_GET_BLOCKS_CREATE_ZERO (EXT4_GET_BLOCKS_CREATE |\
EXT4_GET_BLOCKS_ZERO)
/*
* The bit position of these flags must not overlap with any of the
* EXT4_GET_BLOCKS_*. They are used by ext4_find_extent(),
* read_extent_tree_block(), ext4_split_extent_at(),
* ext4_ext_insert_extent(), and ext4_ext_create_new_leaf().
* EXT4_EX_NOCACHE is used to indicate that the we shouldn't be
* caching the extents when reading from the extent tree while a
* truncate or punch hole operation is in progress.
*/
#define EXT4_EX_NOCACHE 0x40000000
#define EXT4_EX_FORCE_CACHE 0x20000000
/*
* Flags used by ext4_free_blocks
*/
#define EXT4_FREE_BLOCKS_METADATA 0x0001
#define EXT4_FREE_BLOCKS_FORGET 0x0002
#define EXT4_FREE_BLOCKS_VALIDATED 0x0004
#define EXT4_FREE_BLOCKS_NO_QUOT_UPDATE 0x0008
#define EXT4_FREE_BLOCKS_NOFREE_FIRST_CLUSTER 0x0010
#define EXT4_FREE_BLOCKS_NOFREE_LAST_CLUSTER 0x0020
/* Encryption algorithms */
#define EXT4_ENCRYPTION_MODE_INVALID 0
#define EXT4_ENCRYPTION_MODE_AES_256_XTS 1
#define EXT4_ENCRYPTION_MODE_AES_256_GCM 2
#define EXT4_ENCRYPTION_MODE_AES_256_CBC 3
#define EXT4_ENCRYPTION_MODE_AES_256_CTS 4
#include "ext4_crypto.h"
/*
* ioctl commands
*/
#define EXT4_IOC_GETFLAGS FS_IOC_GETFLAGS
#define EXT4_IOC_SETFLAGS FS_IOC_SETFLAGS
#define EXT4_IOC_GETVERSION _IOR('f', 3, long)
#define EXT4_IOC_SETVERSION _IOW('f', 4, long)
#define EXT4_IOC_GETVERSION_OLD FS_IOC_GETVERSION
#define EXT4_IOC_SETVERSION_OLD FS_IOC_SETVERSION
#define EXT4_IOC_GETRSVSZ _IOR('f', 5, long)
#define EXT4_IOC_SETRSVSZ _IOW('f', 6, long)
#define EXT4_IOC_GROUP_EXTEND _IOW('f', 7, unsigned long)
#define EXT4_IOC_GROUP_ADD _IOW('f', 8, struct ext4_new_group_input)
#define EXT4_IOC_MIGRATE _IO('f', 9)
/* note ioctl 10 reserved for an early version of the FIEMAP ioctl */
/* note ioctl 11 reserved for filesystem-independent FIEMAP ioctl */
#define EXT4_IOC_ALLOC_DA_BLKS _IO('f', 12)
#define EXT4_IOC_MOVE_EXT _IOWR('f', 15, struct move_extent)
#define EXT4_IOC_RESIZE_FS _IOW('f', 16, __u64)
#define EXT4_IOC_SWAP_BOOT _IO('f', 17)
#define EXT4_IOC_PRECACHE_EXTENTS _IO('f', 18)
#define EXT4_IOC_SET_ENCRYPTION_POLICY _IOR('f', 19, struct ext4_encryption_policy)
#define EXT4_IOC_GET_ENCRYPTION_PWSALT _IOW('f', 20, __u8[16])
#define EXT4_IOC_GET_ENCRYPTION_POLICY _IOW('f', 21, struct ext4_encryption_policy)
#ifndef FS_IOC_FSGETXATTR
/* Until the uapi changes get merged for project quota... */
#define FS_IOC_FSGETXATTR _IOR('X', 31, struct fsxattr)
#define FS_IOC_FSSETXATTR _IOW('X', 32, struct fsxattr)
/*
* Structure for FS_IOC_FSGETXATTR and FS_IOC_FSSETXATTR.
*/
struct fsxattr {
__u32 fsx_xflags; /* xflags field value (get/set) */
__u32 fsx_extsize; /* extsize field value (get/set)*/
__u32 fsx_nextents; /* nextents field value (get) */
__u32 fsx_projid; /* project identifier (get/set) */
unsigned char fsx_pad[12];
};
/*
* Flags for the fsx_xflags field
*/
#define FS_XFLAG_REALTIME 0x00000001 /* data in realtime volume */
#define FS_XFLAG_PREALLOC 0x00000002 /* preallocated file extents */
#define FS_XFLAG_IMMUTABLE 0x00000008 /* file cannot be modified */
#define FS_XFLAG_APPEND 0x00000010 /* all writes append */
#define FS_XFLAG_SYNC 0x00000020 /* all writes synchronous */
#define FS_XFLAG_NOATIME 0x00000040 /* do not update access time */
#define FS_XFLAG_NODUMP 0x00000080 /* do not include in backups */
#define FS_XFLAG_RTINHERIT 0x00000100 /* create with rt bit set */
#define FS_XFLAG_PROJINHERIT 0x00000200 /* create with parents projid */
#define FS_XFLAG_NOSYMLINKS 0x00000400 /* disallow symlink creation */
#define FS_XFLAG_EXTSIZE 0x00000800 /* extent size allocator hint */
#define FS_XFLAG_EXTSZINHERIT 0x00001000 /* inherit inode extent size */
#define FS_XFLAG_NODEFRAG 0x00002000 /* do not defragment */
#define FS_XFLAG_FILESTREAM 0x00004000 /* use filestream allocator */
#define FS_XFLAG_HASATTR 0x80000000 /* no DIFLAG for this */
#endif /* !defined(FS_IOC_FSGETXATTR) */
#define EXT4_IOC_FSGETXATTR FS_IOC_FSGETXATTR
#define EXT4_IOC_FSSETXATTR FS_IOC_FSSETXATTR
#if defined(__KERNEL__) && defined(CONFIG_COMPAT)
/*
* ioctl commands in 32 bit emulation
*/
#define EXT4_IOC32_GETFLAGS FS_IOC32_GETFLAGS
#define EXT4_IOC32_SETFLAGS FS_IOC32_SETFLAGS
#define EXT4_IOC32_GETVERSION _IOR('f', 3, int)
#define EXT4_IOC32_SETVERSION _IOW('f', 4, int)
#define EXT4_IOC32_GETRSVSZ _IOR('f', 5, int)
#define EXT4_IOC32_SETRSVSZ _IOW('f', 6, int)
#define EXT4_IOC32_GROUP_EXTEND _IOW('f', 7, unsigned int)
#define EXT4_IOC32_GROUP_ADD _IOW('f', 8, struct compat_ext4_new_group_input)
#define EXT4_IOC32_GETVERSION_OLD FS_IOC32_GETVERSION
#define EXT4_IOC32_SETVERSION_OLD FS_IOC32_SETVERSION
#endif
/* Max physical block we can address w/o extents */
#define EXT4_MAX_BLOCK_FILE_PHYS 0xFFFFFFFF
/*
* 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 */
__le32 i_projid; /* Project ID */
};
struct move_extent {
__u32 reserved; /* should be zero */
__u32 donor_fd; /* donor file descriptor */
__u64 orig_start; /* logical start offset in block for orig */
__u64 donor_start; /* logical start offset in block for donor */
__u64 len; /* block length to be moved */
__u64 moved_len; /* moved block length */
};
#define EXT4_EPOCH_BITS 2
#define EXT4_EPOCH_MASK ((1 << EXT4_EPOCH_BITS) - 1)
#define EXT4_NSEC_MASK (~0UL << EXT4_EPOCH_BITS)
/*
* Extended fields will fit into an inode if the filesystem was formatted
* with large inodes (-I 256 or larger) and there are not currently any EAs
* consuming all of the available space. For new inodes we always reserve
* enough space for the kernel's known extended fields, but for inodes
* created with an old kernel this might not have been the case. None of
* the extended inode fields is critical for correct filesystem operation.
* This macro checks if a certain field fits in the inode. Note that
* inode-size = GOOD_OLD_INODE_SIZE + i_extra_isize
*/
#define EXT4_FITS_IN_INODE(ext4_inode, einode, field) \
((offsetof(typeof(*ext4_inode), field) + \
sizeof((ext4_inode)->field)) \
<= (EXT4_GOOD_OLD_INODE_SIZE + \
(einode)->i_extra_isize)) \
/*
* We use an encoding that preserves the times for extra epoch "00":
*
* extra msb of adjust for signed
* epoch 32-bit 32-bit tv_sec to
* bits time decoded 64-bit tv_sec 64-bit tv_sec valid time range
* 0 0 1 -0x80000000..-0x00000001 0x000000000 1901-12-13..1969-12-31
* 0 0 0 0x000000000..0x07fffffff 0x000000000 1970-01-01..2038-01-19
* 0 1 1 0x080000000..0x0ffffffff 0x100000000 2038-01-19..2106-02-07
* 0 1 0 0x100000000..0x17fffffff 0x100000000 2106-02-07..2174-02-25
* 1 0 1 0x180000000..0x1ffffffff 0x200000000 2174-02-25..2242-03-16
* 1 0 0 0x200000000..0x27fffffff 0x200000000 2242-03-16..2310-04-04
* 1 1 1 0x280000000..0x2ffffffff 0x300000000 2310-04-04..2378-04-22
* 1 1 0 0x300000000..0x37fffffff 0x300000000 2378-04-22..2446-05-10
*
* Note that previous versions of the kernel on 64-bit systems would
* incorrectly use extra epoch bits 1,1 for dates between 1901 and
* 1970. e2fsck will correct this, assuming that it is run on the
* affected filesystem before 2242.
*/
static inline __le32 ext4_encode_extra_time(struct timespec *time)
{
u32 extra = sizeof(time->tv_sec) > 4 ?
((time->tv_sec - (s32)time->tv_sec) >> 32) & EXT4_EPOCH_MASK : 0;
return cpu_to_le32(extra | (time->tv_nsec << EXT4_EPOCH_BITS));
}
static inline void ext4_decode_extra_time(struct timespec *time, __le32 extra)
{
if (unlikely(sizeof(time->tv_sec) > 4 &&
(extra & cpu_to_le32(EXT4_EPOCH_MASK)))) {
#if LINUX_VERSION_CODE < KERNEL_VERSION(4,20,0)
/* Handle legacy encoding of pre-1970 dates with epoch
* bits 1,1. We assume that by kernel version 4.20,
* everyone will have run fsck over the affected
* filesystems to correct the problem. (This
* backwards compatibility may be removed before this
* time, at the discretion of the ext4 developers.)
*/
u64 extra_bits = le32_to_cpu(extra) & EXT4_EPOCH_MASK;
if (extra_bits == 3 && ((time->tv_sec) & 0x80000000) != 0)
extra_bits = 0;
time->tv_sec += extra_bits << 32;
#else
time->tv_sec += (u64)(le32_to_cpu(extra) & EXT4_EPOCH_MASK) << 32;
#endif
}
time->tv_nsec = (le32_to_cpu(extra) & EXT4_NSEC_MASK) >> EXT4_EPOCH_BITS;
}
#define EXT4_INODE_SET_XTIME(xtime, inode, raw_inode) \
do { \
(raw_inode)->xtime = cpu_to_le32((inode)->xtime.tv_sec); \
if (EXT4_FITS_IN_INODE(raw_inode, EXT4_I(inode), xtime ## _extra)) \
(raw_inode)->xtime ## _extra = \
ext4_encode_extra_time(&(inode)->xtime); \
} while (0)
#define EXT4_EINODE_SET_XTIME(xtime, einode, raw_inode) \
do { \
if (EXT4_FITS_IN_INODE(raw_inode, einode, xtime)) \
(raw_inode)->xtime = cpu_to_le32((einode)->xtime.tv_sec); \
if (EXT4_FITS_IN_INODE(raw_inode, einode, xtime ## _extra)) \
(raw_inode)->xtime ## _extra = \
ext4_encode_extra_time(&(einode)->xtime); \
} while (0)
#define EXT4_INODE_GET_XTIME(xtime, inode, raw_inode) \
do { \
(inode)->xtime.tv_sec = (signed)le32_to_cpu((raw_inode)->xtime); \
if (EXT4_FITS_IN_INODE(raw_inode, EXT4_I(inode), xtime ## _extra)) \
ext4_decode_extra_time(&(inode)->xtime, \
raw_inode->xtime ## _extra); \
else \
(inode)->xtime.tv_nsec = 0; \
} while (0)
#define EXT4_EINODE_GET_XTIME(xtime, einode, raw_inode) \
do { \
if (EXT4_FITS_IN_INODE(raw_inode, einode, xtime)) \
(einode)->xtime.tv_sec = \
(signed)le32_to_cpu((raw_inode)->xtime); \
else \
(einode)->xtime.tv_sec = 0; \
if (EXT4_FITS_IN_INODE(raw_inode, einode, xtime ## _extra)) \
ext4_decode_extra_time(&(einode)->xtime, \
raw_inode->xtime ## _extra); \
else \
(einode)->xtime.tv_nsec = 0; \
} while (0)
#define i_disk_version osd1.linux1.l_i_version
#if defined(__KERNEL__) || defined(__linux__)
#define i_reserved1 osd1.linux1.l_i_reserved1
#define i_file_acl_high osd2.linux2.l_i_file_acl_high
#define i_blocks_high osd2.linux2.l_i_blocks_high
#define i_uid_low i_uid
#define i_gid_low i_gid
#define i_uid_high osd2.linux2.l_i_uid_high
#define i_gid_high osd2.linux2.l_i_gid_high
#define i_checksum_lo osd2.linux2.l_i_checksum_lo
#elif defined(__GNU__)
#define i_translator osd1.hurd1.h_i_translator
#define i_uid_high osd2.hurd2.h_i_uid_high
#define i_gid_high osd2.hurd2.h_i_gid_high
#define i_author osd2.hurd2.h_i_author
#elif defined(__masix__)
#define i_reserved1 osd1.masix1.m_i_reserved1
#define i_file_acl_high osd2.masix2.m_i_file_acl_high
#define i_reserved2 osd2.masix2.m_i_reserved2
#endif /* defined(__KERNEL__) || defined(__linux__) */
#include "extents_status.h"
/*
* fourth extended file system inode data in memory
*/
struct ext4_inode_info {
__le32 i_data[15]; /* unconverted */
__u32 i_dtime;
ext4_fsblk_t i_file_acl;
/*
* i_block_group is the number of the block group which contains
* this file's inode. Constant across the lifetime of the inode,
* it is ued for making block allocation decisions - we try to
* place a file's data blocks near its inode block, and new inodes
* near to their parent directory's inode.
*/
ext4_group_t i_block_group;
ext4_lblk_t i_dir_start_lookup;
#if (BITS_PER_LONG < 64)
unsigned long i_state_flags; /* Dynamic state flags */
#endif
unsigned long i_flags;
/*
* Extended attributes can be read independently of the main file
* data. Taking i_mutex even when reading would cause contention
* between readers of EAs and writers of regular file data, so
* instead we synchronize on xattr_sem when reading or changing
* EAs.
*/
struct rw_semaphore xattr_sem;
struct list_head i_orphan; /* unlinked but open inodes */
/*
* i_disksize keeps track of what the inode size is ON DISK, not
* in memory. During truncate, i_size is set to the new size by
* the VFS prior to calling ext4_truncate(), but the filesystem won't
* set i_disksize to 0 until the truncate is actually under way.
*
* The intent is that i_disksize always represents the blocks which
* are used by this file. This allows recovery to restart truncate
* on orphans if we crash during truncate. We actually write i_disksize
* into the on-disk inode when writing inodes out, instead of i_size.
*
* The only time when i_disksize and i_size may be different is when
* a truncate is in progress. The only things which change i_disksize
* are ext4_get_block (growth) and ext4_truncate (shrinkth).
*/
loff_t i_disksize;
/*
* i_data_sem is for serialising ext4_truncate() against
* ext4_getblock(). In the 2.4 ext2 design, great chunks of inode's
* data tree are chopped off during truncate. We can't do that in
* ext4 because whenever we perform intermediate commits during
* truncate, the inode and all the metadata blocks *must* be in a
* consistent state which allows truncation of the orphans to restart
* during recovery. Hence we must fix the get_block-vs-truncate race
* by other means, so we have i_data_sem.
*/
struct rw_semaphore i_data_sem;
/*
* i_mmap_sem is for serializing page faults with truncate / punch hole
* operations. We have to make sure that new page cannot be faulted in
* a section of the inode that is being punched. We cannot easily use
* i_data_sem for this since we need protection for the whole punch
* operation and i_data_sem ranks below transaction start so we have
* to occasionally drop it.
*/
struct rw_semaphore i_mmap_sem;
struct inode vfs_inode;
struct jbd2_inode *jinode;
spinlock_t i_raw_lock; /* protects updates to the raw inode */
/*
* File creation time. Its function is same as that of
* struct timespec i_{a,c,m}time in the generic inode.
*/
struct timespec i_crtime;
/* mballoc */
struct list_head i_prealloc_list;
spinlock_t i_prealloc_lock;
/* extents status tree */
struct ext4_es_tree i_es_tree;