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 // SPDX-License-Identifier: GPL-2.0
 /*
  *  ext4.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 _EXT4_H
 #define _EXT4_H
 
 #include <linux/refcount.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/wait.h>
 #include <linux/sched/signal.h>
 #include <linux/blockgroup_lock.h>
 #include <linux/percpu_counter.h>
 #include <linux/ratelimit.h>
 #include <crypto/hash.h>
 #include <linux/falloc.h>
 #include <linux/percpu-rwsem.h>
 #include <linux/fiemap.h>
 #ifdef __KERNEL__
 #include <linux/compat.h>
 #endif
 
 #include <linux/fscrypt.h>
 #include <linux/fsverity.h>
 
 #include <linux/compiler.h>
 
 /*
  * 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 enable ext4_ext_show_path/leaf/move in extents.c
   */
 #define EXT_DEBUG__
 
 /*
  * Dynamic printk for controlled extents debugging.
  */
 #ifdef CONFIG_EXT4_DEBUG
 #define ext_debug(ino, fmt, ...)                    \
     pr_debug("[%s/%d] EXT4-fs (%s): ino %lu: (%s, %d): %s:" fmt,    \
          current->comm, task_pid_nr(current),           \
          ino->i_sb->s_id, ino->i_ino, __FILE__, __LINE__,   \
          __func__, ##__VA_ARGS__)
 #else
 #define ext_debug(ino, fmt, ...)    no_printk(fmt, ##__VA_ARGS__)
 #endif
 
 #define ASSERT(assert)                      \
 do {                                    \
     if (unlikely(!(assert))) {                  \
         printk(KERN_EMERG                   \
                "Assertion failure in %s() at %s:%d: '%s'\n",    \
                __func__, __FILE__, __LINE__, #assert);      \
         BUG();                          \
     }                               \
 } while (0)
 
 /* 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
 /* Do strict check for free blocks while retrying block allocation */
 #define EXT4_MB_STRICT_CHECK        0x4000
 /* Large fragment size list lookup succeeded at least once for cr = 0 */
 #define EXT4_MB_CR0_OPTIMIZED       0x8000
 /* Avg fragment size rb tree lookup succeeded at least once for cr = 1 */
 #define EXT4_MB_CR1_OPTIMIZED       0x00010000
 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        BIT(BH_New)
 #define EXT4_MAP_MAPPED     BIT(BH_Mapped)
 #define EXT4_MAP_UNWRITTEN  BIT(BH_Unwritten)
 #define EXT4_MAP_BOUNDARY   BIT(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;
 };
 
 /*
  * Block validity checking, system zone rbtree.
  */
 struct ext4_system_blocks {
     struct rb_root root;
     struct rcu_head rcu;
 };
 
 /*
  * Flags for ext4_io_end->flags
  */
 #define EXT4_IO_END_UNWRITTEN   0x0001
 
 struct ext4_io_end_vec {
     struct list_head list;      /* list of io_end_vec */
     loff_t offset;          /* offset in the file */
     ssize_t size;           /* size of the extent */
 };
 
 /*
  * 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 */
     refcount_t      count;      /* reference counter */
     struct list_head    list_vec;   /* list of ext4_io_end_vec */
 } 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
 #define EXT4_MAX_CLUSTER_LOG_SIZE   30
 #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)))
 #define EXT4_MAX_BLOCKS(size, offset, blkbits) \
     ((EXT4_BLOCK_ALIGN(size + offset, blkbits) >> blkbits) - (offset >> \
                                   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))
 /* Fill in the low bits to get the last block of the cluster */
 #define EXT4_LBLK_CFILL(sbi, lblk) ((lblk) |                \
                     ((ext4_lblk_t) (sbi)->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_VERITY_FL          0x00100000 /* Verity protected inode */
 #define EXT4_EA_INODE_FL            0x00200000 /* Inode used for large EA */
 /* 0x00400000 was formerly EXT4_EOFBLOCKS_FL */
 
 #define EXT4_DAX_FL         0x02000000 /* Inode is DAX */
 
 #define EXT4_INLINE_DATA_FL     0x10000000 /* Inode has inline data. */
 #define EXT4_PROJINHERIT_FL     0x20000000 /* Create with parents projid */
 #define EXT4_CASEFOLD_FL        0x40000000 /* Casefolded directory */
 #define EXT4_RESERVED_FL        0x80000000 /* reserved for ext4 lib */
 
 /* User modifiable flags */
 #define EXT4_FL_USER_MODIFIABLE     (EXT4_SECRM_FL | \
                      EXT4_UNRM_FL | \
                      EXT4_COMPR_FL | \
                      EXT4_SYNC_FL | \
                      EXT4_IMMUTABLE_FL | \
                      EXT4_APPEND_FL | \
                      EXT4_NODUMP_FL | \
                      EXT4_NOATIME_FL | \
                      EXT4_JOURNAL_DATA_FL | \
                      EXT4_NOTAIL_FL | \
                      EXT4_DIRSYNC_FL | \
                      EXT4_TOPDIR_FL | \
                      EXT4_EXTENTS_FL | \
                      0x00400000 /* EXT4_EOFBLOCKS_FL */ | \
                      EXT4_DAX_FL | \
                      EXT4_PROJINHERIT_FL | \
                      EXT4_CASEFOLD_FL)
 
 /* User visible flags */
 #define EXT4_FL_USER_VISIBLE        (EXT4_FL_USER_MODIFIABLE | \
                      EXT4_DIRTY_FL | \
                      EXT4_COMPRBLK_FL | \
                      EXT4_NOCOMPR_FL | \
                      EXT4_ENCRYPT_FL | \
                      EXT4_INDEX_FL | \
                      EXT4_VERITY_FL | \
                      EXT4_INLINE_DATA_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 | EXT4_CASEFOLD_FL |\
                EXT4_DAX_FL)
 
 /* Flags that are appropriate for regular files (all but dir-specific ones). */
 #define EXT4_REG_FLMASK (~(EXT4_DIRSYNC_FL | EXT4_TOPDIR_FL | EXT4_CASEFOLD_FL |\
                EXT4_PROJINHERIT_FL))
 
 /* Flags that are appropriate for non-directories/regular files. */
 #define EXT4_OTHER_FLMASK (EXT4_NODUMP_FL | EXT4_NOATIME_FL)
 
 /* The only flags that should be swapped */
 #define EXT4_FL_SHOULD_SWAP (EXT4_HUGE_FILE_FL | EXT4_EXTENTS_FL)
 
 /* Flags which are mutually exclusive to DAX */
 #define EXT4_DAX_MUT_EXCL (EXT4_VERITY_FL | EXT4_ENCRYPT_FL |\
                EXT4_JOURNAL_DATA_FL | EXT4_INLINE_DATA_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_VERITY   = 20,   /* Verity protected inode */
     EXT4_INODE_EA_INODE = 21,   /* Inode used for large EA */
 /* 22 was formerly EXT4_INODE_EOFBLOCKS */
     EXT4_INODE_DAX      = 25,   /* Inode is DAX */
     EXT4_INODE_INLINE_DATA  = 28,   /* Data in inode. */
     EXT4_INODE_PROJINHERIT  = 29,   /* Create with parents projid */
     EXT4_INODE_CASEFOLD = 30,   /* Casefolded directory */
     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(VERITY);
     CHECK_FLAG_VALUE(EA_INODE);
     CHECK_FLAG_VALUE(INLINE_DATA);
     CHECK_FLAG_VALUE(PROJINHERIT);
     CHECK_FLAG_VALUE(CASEFOLD);
     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 mdata_blocks;
     __u32 free_clusters_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
     /* 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)
     /* Caller will submit data before dropping transaction handle. This
      * allows jbd2 to avoid submitting data before commit. */
 #define EXT4_GET_BLOCKS_IO_SUBMIT       0x0400
     /* Caller is in the atomic contex, find extent if it has been cached */
 #define EXT4_GET_BLOCKS_CACHED_NOWAIT       0x0800
 
 /*
  * 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
 #define EXT4_EX_NOFAIL              0x10000000
 
 /*
  * 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
 #define EXT4_FREE_BLOCKS_RERESERVE_CLUSTER      0x0040
 
 /*
  * ioctl commands
  */
 #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)
 /* ioctl codes 19--39 are reserved for fscrypt */
 #define EXT4_IOC_CLEAR_ES_CACHE     _IO('f', 40)
 #define EXT4_IOC_GETSTATE       _IOW('f', 41, __u32)
 #define EXT4_IOC_GET_ES_CACHE       _IOWR('f', 42, struct fiemap)
 #define EXT4_IOC_CHECKPOINT     _IOW('f', 43, __u32)
 #define EXT4_IOC_GETFSUUID      _IOR('f', 44, struct fsuuid)
 #define EXT4_IOC_SETFSUUID      _IOW('f', 44, struct fsuuid)
 
 #define EXT4_IOC_SHUTDOWN _IOR ('X', 125, __u32)
 
 /*
  * Flags for going down operation
  */
 #define EXT4_GOING_FLAGS_DEFAULT        0x0 /* going down */
 #define EXT4_GOING_FLAGS_LOGFLUSH       0x1 /* flush log but not data */
 #define EXT4_GOING_FLAGS_NOLOGFLUSH     0x2 /* don't flush log nor data */
 
 /*
  * Flags returned by EXT4_IOC_GETSTATE
  *
  * We only expose to userspace a subset of the state flags in
  * i_state_flags
  */
 #define EXT4_STATE_FLAG_EXT_PRECACHED   0x00000001
 #define EXT4_STATE_FLAG_NEW     0x00000002
 #define EXT4_STATE_FLAG_NEWENTRY    0x00000004
 #define EXT4_STATE_FLAG_DA_ALLOC_CLOSE  0x00000008
 
 /* flags for ioctl EXT4_IOC_CHECKPOINT */
 #define EXT4_IOC_CHECKPOINT_FLAG_DISCARD    0x1
 #define EXT4_IOC_CHECKPOINT_FLAG_ZEROOUT    0x2
 #define EXT4_IOC_CHECKPOINT_FLAG_DRY_RUN    0x4
 #define EXT4_IOC_CHECKPOINT_FLAG_VALID      (EXT4_IOC_CHECKPOINT_FLAG_DISCARD | \
                         EXT4_IOC_CHECKPOINT_FLAG_ZEROOUT | \
                         EXT4_IOC_CHECKPOINT_FLAG_DRY_RUN)
 
 /*
  * Structure for EXT4_IOC_GETFSUUID/EXT4_IOC_SETFSUUID
  */
 struct fsuuid {
     __u32       fsu_len;
     __u32       fsu_flags;
     __u8        fsu_uuid[];
 };
 
 #if defined(__KERNEL__) && defined(CONFIG_COMPAT)
 /*
  * ioctl commands in 32 bit emulation
  */
 #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
 
 /*
  * Returned by EXT4_IOC_GET_ES_CACHE as an additional possible flag.
  * It indicates that the entry in extent status cache is for a hole.
  */
 #define EXT4_FIEMAP_EXTENT_HOLE     0x08000000
 
 /* Max physical block we can address w/o extents */
 #define EXT4_MAX_BLOCK_FILE_PHYS    0xFFFFFFFF
 
 /* Max logical block we can support */
 #define EXT4_MAX_LOGICAL_BLOCK      0xFFFFFFFE
 
 /*
  * 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 timespec64 *time)
 {
     u32 extra =((time->tv_sec - (s32)time->tv_sec) >> 32) & EXT4_EPOCH_MASK;
     return cpu_to_le32(extra | (time->tv_nsec << EXT4_EPOCH_BITS));
 }
 
 static inline void ext4_decode_extra_time(struct timespec64 *time,
                       __le32 extra)
 {
     if (unlikely(extra & cpu_to_le32(EXT4_EPOCH_MASK)))
         time->tv_sec += (u64)(le32_to_cpu(extra) & EXT4_EPOCH_MASK) << 32;
     time->tv_nsec = (le32_to_cpu(extra) & EXT4_NSEC_MASK) >> EXT4_EPOCH_BITS;
 }
 
 #define EXT4_INODE_SET_XTIME(xtime, inode, raw_inode)               \
 do {                                        \
     if (EXT4_FITS_IN_INODE(raw_inode, EXT4_I(inode), xtime ## _extra))     {\
         (raw_inode)->xtime = cpu_to_le32((inode)->xtime.tv_sec);    \
         (raw_inode)->xtime ## _extra =                  \
                 ext4_encode_extra_time(&(inode)->xtime);    \
         }                               \
     else    \
         (raw_inode)->xtime = cpu_to_le32(clamp_t(int32_t, (inode)->xtime.tv_sec, S32_MIN, S32_MAX));    \
 } 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"
 #include "fast_commit.h"
 
 /*
  * Lock subclasses for i_data_sem in the ext4_inode_info structure.
  *
  * These are needed to avoid lockdep false positives when we need to
  * allocate blocks to the quota inode during ext4_map_blocks(), while
  * holding i_data_sem for a normal (non-quota) inode.  Since we don't
  * do quota tracking for the quota inode, this avoids deadlock (as
  * well as infinite recursion, since it isn't turtles all the way
  * down...)
  *
  *  I_DATA_SEM_NORMAL - Used for most inodes
  *  I_DATA_SEM_OTHER  - Used by move_inode.c for the second normal inode
  *            where the second inode has larger inode number
  *            than the first
  *  I_DATA_SEM_QUOTA  - Used for quota inodes only
  */
 enum {
     I_DATA_SEM_NORMAL = 0,
     I_DATA_SEM_OTHER,
     I_DATA_SEM_QUOTA,
 };
 
 
 /*
  * 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 used 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_rwsem 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;
 
     /*
      * Inodes with EXT4_STATE_ORPHAN_FILE use i_orphan_idx. Otherwise
      * i_orphan is used.
      */
     union {
         struct list_head i_orphan;  /* unlinked but open inodes */
         unsigned int i_orphan_idx;  /* Index in orphan file */
     };
 
     /* Fast commit related info */
 
     /* For tracking dentry create updates */
     struct list_head i_fc_dilist;
     struct list_head i_fc_list; /*
                      * inodes that need fast commit
                      * protected by sbi->s_fc_lock.
                      */
 
     /* Start of lblk range that needs to be committed in this fast commit */
     ext4_lblk_t i_fc_lblk_start;
 
     /* End of lblk range that needs to be committed in this fast commit */
     ext4_lblk_t i_fc_lblk_len;
 
     /* Number of ongoing updates on this inode */
     atomic_t  i_fc_updates;
 
     /* Fast commit wait queue for this inode */
     wait_queue_head_t i_fc_wait;
 
     /* Protect concurrent accesses on i_fc_lblk_start, i_fc_lblk_len */
     struct mutex i_fc_lock;
 
     /*
      * 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;
     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 timespec64 i_{a,c,m}time in the generic inode.
      */
     struct timespec64 i_crtime;
 
     /* mballoc */
     atomic_t i_prealloc_active;
     struct list_head i_prealloc_list;
     spinlock_t i_prealloc_lock;
 
     /* extents status tree */
     struct ext4_es_tree i_es_tree;
     rwlock_t i_es_lock;
     struct list_head i_es_list;
     unsigned int i_es_all_nr;   /* protected by i_es_lock */
     unsigned int i_es_shk_nr;   /* protected by i_es_lock */
     ext4_lblk_t i_es_shrink_lblk;   /* Offset where we start searching for
                        extents to shrink. Protected by
                        i_es_lock  */
 
     /* ialloc */
     ext4_group_t    i_last_alloc_group;
 
     /* allocation reservation info for delalloc */
     /* In case of bigalloc, this refer to clusters rather than blocks */
     unsigned int i_reserved_data_blocks;
 
     /* pending cluster reservations for bigalloc file systems */
     struct ext4_pending_tree i_pending_tree;
 
     /* on-disk additional length */
     __u16 i_extra_isize;
 
     /* Indicate the inline data space. */
     u16 i_inline_off;
     u16 i_inline_size;
 
 #ifdef CONFIG_QUOTA
     /* quota space reservation, managed internally by quota code */
     qsize_t i_reserved_quota;
 #endif
 
     /* Lock protecting lists below */
     spinlock_t i_completed_io_lock;
     /*
      * Completed IOs that need unwritten extents handling and have
      * transaction reserved
      */
     struct list_head i_rsv_conversion_list;
     struct work_struct i_rsv_conversion_work;
     atomic_t i_unwritten; /* Nr. of inflight conversions pending */
 
     spinlock_t i_block_reservation_lock;
 
     /*
      * Transactions that contain inode's metadata needed to complete
      * fsync and fdatasync, respectively.
      */
     tid_t i_sync_tid;
     tid_t i_datasync_tid;
 
 #ifdef CONFIG_QUOTA
     struct dquot *i_dquot[MAXQUOTAS];
 #endif
 
     /* Precomputed uuid+inum+igen checksum for seeding inode checksums */
     __u32 i_csum_seed;
 
     kprojid_t i_projid;
 };
 
 /*
  * File system states
  */
 #define EXT4_VALID_FS           0x0001  /* Unmounted cleanly */
 #define EXT4_ERROR_FS           0x0002  /* Errors detected */
 #define EXT4_ORPHAN_FS          0x0004  /* Orphans being recovered */
 #define EXT4_FC_REPLAY          0x0020  /* Fast commit replay ongoing */
 
 /*
  * Misc. filesystem flags
  */
 #define EXT2_FLAGS_SIGNED_HASH      0x0001  /* Signed dirhash in use */
 #define EXT2_FLAGS_UNSIGNED_HASH    0x0002  /* Unsigned dirhash in use */
 #define EXT2_FLAGS_TEST_FILESYS     0x0004  /* to test development code */
 
 /*
  * Mount flags set via mount options or defaults
  */
 #define EXT4_MOUNT_NO_MBCACHE       0x00001 /* Do not use mbcache */
 #define EXT4_MOUNT_GRPID        0x00004 /* Create files with directory's group */
 #define EXT4_MOUNT_DEBUG        0x00008 /* Some debugging messages */
 #define EXT4_MOUNT_ERRORS_CONT      0x00010 /* Continue on errors */
 #define EXT4_MOUNT_ERRORS_RO        0x00020 /* Remount fs ro on errors */
 #define EXT4_MOUNT_ERRORS_PANIC     0x00040 /* Panic on errors */
 #define EXT4_MOUNT_ERRORS_MASK      0x00070
 #define EXT4_MOUNT_MINIX_DF     0x00080 /* Mimics the Minix statfs */
 #define EXT4_MOUNT_NOLOAD       0x00100 /* Don't use existing journal*/
 #ifdef CONFIG_FS_DAX
 #define EXT4_MOUNT_DAX_ALWAYS       0x00200 /* Direct Access */
 #else
 #define EXT4_MOUNT_DAX_ALWAYS       0
 #endif
 #define EXT4_MOUNT_DATA_FLAGS       0x00C00 /* Mode for data writes: */
 #define EXT4_MOUNT_JOURNAL_DATA     0x00400 /* Write data to journal */
 #define EXT4_MOUNT_ORDERED_DATA     0x00800 /* Flush data before commit */
 #define EXT4_MOUNT_WRITEBACK_DATA   0x00C00 /* No data ordering */
 #define EXT4_MOUNT_UPDATE_JOURNAL   0x01000 /* Update the journal format */
 #define EXT4_MOUNT_NO_UID32     0x02000  /* Disable 32-bit UIDs */
 #define EXT4_MOUNT_XATTR_USER       0x04000 /* Extended user attributes */
 #define EXT4_MOUNT_POSIX_ACL        0x08000 /* POSIX Access Control Lists */
 #define EXT4_MOUNT_NO_AUTO_DA_ALLOC 0x10000 /* No auto delalloc mapping */
 #define EXT4_MOUNT_BARRIER      0x20000 /* Use block barriers */
 #define EXT4_MOUNT_QUOTA        0x40000 /* Some quota option set */
 #define EXT4_MOUNT_USRQUOTA     0x80000 /* "old" user quota,
                          * enable enforcement for hidden
                          * quota files */
 #define EXT4_MOUNT_GRPQUOTA     0x100000 /* "old" group quota, enable
                           * enforcement for hidden quota
                           * files */
 #define EXT4_MOUNT_PRJQUOTA     0x200000 /* Enable project quota
                           * enforcement */
 #define EXT4_MOUNT_DIOREAD_NOLOCK   0x400000 /* Enable support for dio read nolocking */
 #define EXT4_MOUNT_JOURNAL_CHECKSUM 0x800000 /* Journal checksums */
 #define EXT4_MOUNT_JOURNAL_ASYNC_COMMIT 0x1000000 /* Journal Async Commit */
 #define EXT4_MOUNT_WARN_ON_ERROR    0x2000000 /* Trigger WARN_ON on error */
 #define EXT4_MOUNT_NO_PREFETCH_BLOCK_BITMAPS 0x4000000
 #define EXT4_MOUNT_DELALLOC     0x8000000 /* Delalloc support */
 #define EXT4_MOUNT_DATA_ERR_ABORT   0x10000000 /* Abort on file data write */
 #define EXT4_MOUNT_BLOCK_VALIDITY   0x20000000 /* Block validity checking */
 #define EXT4_MOUNT_DISCARD      0x40000000 /* Issue DISCARD requests */
 #define EXT4_MOUNT_INIT_INODE_TABLE 0x80000000 /* Initialize uninitialized itables */
 
 /*
  * Mount flags set either automatically (could not be set by mount option)
  * based on per file system feature or property or in special cases such as
  * distinguishing between explicit mount option definition and default.
  */
 #define EXT4_MOUNT2_EXPLICIT_DELALLOC   0x00000001 /* User explicitly
                               specified delalloc */
 #define EXT4_MOUNT2_STD_GROUP_SIZE  0x00000002 /* We have standard group
                               size of blocksize * 8
                               blocks */
 #define EXT4_MOUNT2_HURD_COMPAT     0x00000004 /* Support HURD-castrated
                               file systems */
 #define EXT4_MOUNT2_EXPLICIT_JOURNAL_CHECKSUM   0x00000008 /* User explicitly
                         specified journal checksum */
 
 #define EXT4_MOUNT2_JOURNAL_FAST_COMMIT 0x00000010 /* Journal fast commit */
 #define EXT4_MOUNT2_DAX_NEVER       0x00000020 /* Do not allow Direct Access */
 #define EXT4_MOUNT2_DAX_INODE       0x00000040 /* For printing options only */
 #define EXT4_MOUNT2_MB_OPTIMIZE_SCAN    0x00000080 /* Optimize group
                             * scanning in mballoc
                             */
 
 #define clear_opt(sb, opt)      EXT4_SB(sb)->s_mount_opt &= \
                         ~EXT4_MOUNT_##opt
 #define set_opt(sb, opt)        EXT4_SB(sb)->s_mount_opt |= \
                         EXT4_MOUNT_##opt
 #define test_opt(sb, opt)       (EXT4_SB(sb)->s_mount_opt & \
                      EXT4_MOUNT_##opt)
 
 #define clear_opt2(sb, opt)     EXT4_SB(sb)->s_mount_opt2 &= \
                         ~EXT4_MOUNT2_##opt
 #define set_opt2(sb, opt)       EXT4_SB(sb)->s_mount_opt2 |= \
                         EXT4_MOUNT2_##opt
 #define test_opt2(sb, opt)      (EXT4_SB(sb)->s_mount_opt2 & \
                      EXT4_MOUNT2_##opt)
 
 #define ext4_test_and_set_bit       __test_and_set_bit_le
 #define ext4_set_bit            __set_bit_le
 #define ext4_set_bit_atomic     ext2_set_bit_atomic
 #define ext4_test_and_clear_bit     __test_and_clear_bit_le
 #define ext4_clear_bit          __clear_bit_le
 #define ext4_clear_bit_atomic       ext2_clear_bit_atomic
 #define ext4_test_bit           test_bit_le
 #define ext4_find_next_zero_bit     find_next_zero_bit_le
 #define ext4_find_next_bit      find_next_bit_le
 
 extern void mb_set_bits(void *bm, int cur, int len);
 
 /*
  * Maximal mount counts between two filesystem checks
  */
 #define EXT4_DFL_MAX_MNT_COUNT      20  /* Allow 20 mounts */
 #define EXT4_DFL_CHECKINTERVAL      0   /* Don't use interval check */
 
 /*
  * Behaviour when detecting errors
  */
 #define EXT4_ERRORS_CONTINUE        1   /* Continue execution */
 #define EXT4_ERRORS_RO          2   /* Remount fs read-only */
 #define EXT4_ERRORS_PANIC       3   /* Panic */
 #define EXT4_ERRORS_DEFAULT     EXT4_ERRORS_CONTINUE
 
 /* Metadata checksum algorithm codes */
 #define EXT4_CRC32C_CHKSUM      1
 
 #define EXT4_LABEL_MAX          16
 
 /*
  * 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[EXT4_LABEL_MAX];  /* volume name */
 /*88*/  char    s_last_mounted[64] __nonstring; /* 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 */
     __u8    s_encryption_level; /* versioning level for encryption */
     __u8    s_reserved_pad;     /* Padding to next 32bits */
     __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] __nonstring; /* 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] __nonstring;  /* 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_backup_bgs[2];    /* groups with sparse_super2 SBs */
     __u8    s_encrypt_algos[4]; /* Encryption algorithms in use  */
     __u8    s_encrypt_pw_salt[16];  /* Salt used for string2key algorithm */
     __le32  s_lpf_ino;      /* Location of the lost+found inode */
     __le32  s_prj_quota_inum;   /* inode for tracking project quota */
     __le32  s_checksum_seed;    /* crc32c(uuid) if csum_seed set */
     __u8    s_wtime_hi;
     __u8    s_mtime_hi;
     __u8    s_mkfs_time_hi;
     __u8    s_lastcheck_hi;
     __u8    s_first_error_time_hi;
     __u8    s_last_error_time_hi;
     __u8    s_first_error_errcode;
     __u8    s_last_error_errcode;
     __le16  s_encoding;     /* Filename charset encoding */
     __le16  s_encoding_flags;   /* Filename charset encoding flags */
     __le32  s_orphan_file_inum; /* Inode for tracking orphan inodes */
     __le32  s_reserved[94];     /* Padding to the end of the block */
     __le32  s_checksum;     /* crc32c(superblock) */
 };
 
 #define EXT4_S_ERR_LEN (EXT4_S_ERR_END - EXT4_S_ERR_START)
 
 #ifdef __KERNEL__
 
 /* Number of quota types we support */
 #define EXT4_MAXQUOTAS 3
 
 #define EXT4_ENC_UTF8_12_1  1
 
 /* Types of ext4 journal triggers */
 enum ext4_journal_trigger_type {
     EXT4_JTR_ORPHAN_FILE,
     EXT4_JTR_NONE   /* This must be the last entry for indexing to work! */
 };
 
 #define EXT4_JOURNAL_TRIGGER_COUNT EXT4_JTR_NONE
 
 struct ext4_journal_trigger {
     struct jbd2_buffer_trigger_type tr_triggers;
     struct super_block *sb;
 };
 
 static inline struct ext4_journal_trigger *EXT4_TRIGGER(
                 struct jbd2_buffer_trigger_type *trigger)
 {
     return container_of(trigger, struct ext4_journal_trigger, tr_triggers);
 }
 
 #define EXT4_ORPHAN_BLOCK_MAGIC 0x0b10ca04
 
 /* Structure at the tail of orphan block */
 struct ext4_orphan_block_tail {
     __le32 ob_magic;
     __le32 ob_checksum;
 };
 
 static inline int ext4_inodes_per_orphan_block(struct super_block *sb)
 {
     return (sb->s_blocksize - sizeof(struct ext4_orphan_block_tail)) /
             sizeof(u32);
 }
 
 struct ext4_orphan_block {
     atomic_t ob_free_entries;   /* Number of free orphan entries in block */
     struct buffer_head *ob_bh;  /* Buffer for orphan block */
 };
 
 /*
  * Info about orphan file.
  */
 struct ext4_orphan_info {
     int of_blocks;          /* Number of orphan blocks in a file */
     __u32 of_csum_seed;     /* Checksum seed for orphan file */
     struct ext4_orphan_block *of_binfo; /* Array with info about orphan
                          * file blocks */
 };
 
 /*
  * fourth extended-fs super-block data in memory
  */
 struct ext4_sb_info {
     unsigned long s_desc_size;  /* Size of a group descriptor in bytes */
     unsigned long s_inodes_per_block;/* Number of inodes per block */
     unsigned long s_blocks_per_group;/* Number of blocks in a group */
     unsigned long s_clusters_per_group; /* Number of clusters in a group */
     unsigned long s_inodes_per_group;/* Number of inodes in a group */
     unsigned long s_itb_per_group;  /* Number of inode table blocks per group */
     unsigned long s_gdb_count;  /* Number of group descriptor blocks */
     unsigned long s_desc_per_block; /* Number of group descriptors per block */
     ext4_group_t s_groups_count;    /* Number of groups in the fs */
     ext4_group_t s_blockfile_groups;/* Groups acceptable for non-extent files */
     unsigned long s_overhead;  /* # of fs overhead clusters */
     unsigned int s_cluster_ratio;   /* Number of blocks per cluster */
     unsigned int s_cluster_bits;    /* log2 of s_cluster_ratio */
     loff_t s_bitmap_maxbytes;   /* max bytes for bitmap files */
     struct buffer_head * s_sbh; /* Buffer containing the super block */
     struct ext4_super_block *s_es;  /* Pointer to the super block in the buffer */
     struct buffer_head * __rcu *s_group_desc;
     unsigned int s_mount_opt;
     unsigned int s_mount_opt2;
     unsigned long s_mount_flags;
     unsigned int s_def_mount_opt;
     ext4_fsblk_t s_sb_block;
     atomic64_t s_resv_clusters;
     kuid_t s_resuid;
     kgid_t s_resgid;
     unsigned short s_mount_state;
     unsigned short s_pad;
     int s_addr_per_block_bits;
     int s_desc_per_block_bits;
     int s_inode_size;
     int s_first_ino;
     unsigned int s_inode_readahead_blks;
     unsigned int s_inode_goal;
     u32 s_hash_seed[4];
     int s_def_hash_version;
     int s_hash_unsigned;    /* 3 if hash should be unsigned, 0 if not */
     struct percpu_counter s_freeclusters_counter;
     struct percpu_counter s_freeinodes_counter;
     struct percpu_counter s_dirs_counter;
     struct percpu_counter s_dirtyclusters_counter;
     struct percpu_counter s_sra_exceeded_retry_limit;
     struct blockgroup_lock *s_blockgroup_lock;
     struct proc_dir_entry *s_proc;
     struct kobject s_kobj;
     struct completion s_kobj_unregister;
     struct super_block *s_sb;
     struct buffer_head *s_mmp_bh;
 
     /* Journaling */
     struct journal_s *s_journal;
     unsigned long s_ext4_flags;     /* Ext4 superblock flags */
     struct mutex s_orphan_lock; /* Protects on disk list changes */
     struct list_head s_orphan;  /* List of orphaned inodes in on disk
                        list */
     struct ext4_orphan_info s_orphan_info;
     unsigned long s_commit_interval;
     u32 s_max_batch_time;
     u32 s_min_batch_time;
     struct block_device *s_journal_bdev;
 #ifdef CONFIG_QUOTA
     /* Names of quota files with journalled quota */
     char __rcu *s_qf_names[EXT4_MAXQUOTAS];
     int s_jquota_fmt;           /* Format of quota to use */
 #endif
     unsigned int s_want_extra_isize; /* New inodes should reserve # bytes */
     struct ext4_system_blocks __rcu *s_system_blks;
 
 #ifdef EXTENTS_STATS
     /* ext4 extents stats */
     unsigned long s_ext_min;
     unsigned long s_ext_max;
     unsigned long s_depth_max;
     spinlock_t s_ext_stats_lock;
     unsigned long s_ext_blocks;
     unsigned long s_ext_extents;
 #endif
 
     /* for buddy allocator */
     struct ext4_group_info ** __rcu *s_group_info;
     struct inode *s_buddy_cache;
     spinlock_t s_md_lock;
     unsigned short *s_mb_offsets;
     unsigned int *s_mb_maxs;
     unsigned int s_group_info_size;
     unsigned int s_mb_free_pending;
     struct list_head s_freed_data_list; /* List of blocks to be freed
                            after commit completed */
     struct list_head s_discard_list;
     struct work_struct s_discard_work;
     atomic_t s_retry_alloc_pending;
     struct list_head *s_mb_avg_fragment_size;
     rwlock_t *s_mb_avg_fragment_size_locks;
     struct list_head *s_mb_largest_free_orders;
     rwlock_t *s_mb_largest_free_orders_locks;
 
     /* tunables */
     unsigned long s_stripe;
     unsigned int s_mb_max_linear_groups;
     unsigned int s_mb_stream_request;
     unsigned int s_mb_max_to_scan;
     unsigned int s_mb_min_to_scan;
     unsigned int s_mb_stats;
     unsigned int s_mb_order2_reqs;
     unsigned int s_mb_group_prealloc;
     unsigned int s_mb_max_inode_prealloc;
     unsigned int s_max_dir_size_kb;
     /* where last allocation was done - for stream allocation */
     unsigned long s_mb_last_group;
     unsigned long s_mb_last_start;
     unsigned int s_mb_prefetch;
     unsigned int s_mb_prefetch_limit;
 
     /* stats for buddy allocator */
     atomic_t s_bal_reqs;    /* number of reqs with len > 1 */
     atomic_t s_bal_success; /* we found long enough chunks */
     atomic_t s_bal_allocated;   /* in blocks */
     atomic_t s_bal_ex_scanned;  /* total extents scanned */
     atomic_t s_bal_groups_scanned;  /* number of groups scanned */
     atomic_t s_bal_goals;   /* goal hits */
     atomic_t s_bal_breaks;  /* too long searches */
     atomic_t s_bal_2orders; /* 2^order hits */
     atomic_t s_bal_cr0_bad_suggestions;
     atomic_t s_bal_cr1_bad_suggestions;
     atomic64_t s_bal_cX_groups_considered[4];
     atomic64_t s_bal_cX_hits[4];
     atomic64_t s_bal_cX_failed[4];      /* cX loop didn't find blocks */
     atomic_t s_mb_buddies_generated;    /* number of buddies generated */
     atomic64_t s_mb_generation_time;
     atomic_t s_mb_lost_chunks;
     atomic_t s_mb_preallocated;
     atomic_t s_mb_discarded;
     atomic_t s_lock_busy;
 
     /* locality groups */
     struct ext4_locality_group __percpu *s_locality_groups;
 
     /* for write statistics */
     unsigned long s_sectors_written_start;
     u64 s_kbytes_written;
 
     /* the size of zero-out chunk */
     unsigned int s_extent_max_zeroout_kb;
 
     unsigned int s_log_groups_per_flex;
     struct flex_groups * __rcu *s_flex_groups;
     ext4_group_t s_flex_groups_allocated;
 
     /* workqueue for reserved extent conversions (buffered io) */
     struct workqueue_struct *rsv_conversion_wq;
 
     /* timer for periodic error stats printing */
     struct timer_list s_err_report;
 
     /* Lazy inode table initialization info */
     struct ext4_li_request *s_li_request;
     /* Wait multiplier for lazy initialization thread */
     unsigned int s_li_wait_mult;
 
     /* Kernel thread for multiple mount protection */
     struct task_struct *s_mmp_tsk;
 
     /* record the last minlen when FITRIM is called. */
     unsigned long s_last_trim_minblks;
 
     /* Reference to checksum algorithm driver via cryptoapi */
     struct crypto_shash *s_chksum_driver;
 
     /* Precomputed FS UUID checksum for seeding other checksums */
     __u32 s_csum_seed;
 
     /* Reclaim extents from extent status tree */
     struct shrinker s_es_shrinker;
     struct list_head s_es_list; /* List of inodes with reclaimable extents */
     long s_es_nr_inode;
     struct ext4_es_stats s_es_stats;
     struct mb_cache *s_ea_block_cache;
     struct mb_cache *s_ea_inode_cache;
     spinlock_t s_es_lock ____cacheline_aligned_in_smp;
 
     /* Journal triggers for checksum computation */
     struct ext4_journal_trigger s_journal_triggers[EXT4_JOURNAL_TRIGGER_COUNT];
 
     /* Ratelimit ext4 messages. */
     struct ratelimit_state s_err_ratelimit_state;
     struct ratelimit_state s_warning_ratelimit_state;
     struct ratelimit_state s_msg_ratelimit_state;
     atomic_t s_warning_count;
     atomic_t s_msg_count;
 
     /* Encryption policy for '-o test_dummy_encryption' */
     struct fscrypt_dummy_policy s_dummy_enc_policy;
 
     /*
      * Barrier between writepages ops and changing any inode's JOURNAL_DATA
      * or EXTENTS flag.
      */
     struct percpu_rw_semaphore s_writepages_rwsem;
     struct dax_device *s_daxdev;
     u64 s_dax_part_off;
 #ifdef CONFIG_EXT4_DEBUG
     unsigned long s_simulate_fail;
 #endif
     /* Record the errseq of the backing block device */
     errseq_t s_bdev_wb_err;
     spinlock_t s_bdev_wb_lock;
 
     /* Information about errors that happened during this mount */
     spinlock_t s_error_lock;
     int s_add_error_count;
     int s_first_error_code;
     __u32 s_first_error_line;
     __u32 s_first_error_ino;
     __u64 s_first_error_block;
     const char *s_first_error_func;
     time64_t s_first_error_time;
     int s_last_error_code;
     __u32 s_last_error_line;
     __u32 s_last_error_ino;
     __u64 s_last_error_block;
     const char *s_last_error_func;
     time64_t s_last_error_time;
     /*
      * If we are in a context where we cannot update error information in
      * the on-disk superblock, we queue this work to do it.
      */
     struct work_struct s_error_work;
 
     /* Ext4 fast commit sub transaction ID */
     atomic_t s_fc_subtid;
 
     /*
      * After commit starts, the main queue gets locked, and the further
      * updates get added in the staging queue.
      */
 #define FC_Q_MAIN   0
 #define FC_Q_STAGING    1
     struct list_head s_fc_q[2]; /* Inodes staged for fast commit
                      * that have data changes in them.
                      */
     struct list_head s_fc_dentry_q[2];  /* directory entry updates */
     unsigned int s_fc_bytes;
     /*
      * Main fast commit lock. This lock protects accesses to the
      * following fields:
      * ei->i_fc_list, s_fc_dentry_q, s_fc_q, s_fc_bytes, s_fc_bh.
      */
     spinlock_t s_fc_lock;
     struct buffer_head *s_fc_bh;
     struct ext4_fc_stats s_fc_stats;
     tid_t s_fc_ineligible_tid;
 #ifdef CONFIG_EXT4_DEBUG
     int s_fc_debug_max_replay;
 #endif
     struct ext4_fc_replay_state s_fc_replay_state;
 };
 
 static inline struct ext4_sb_info *EXT4_SB(struct super_block *sb)
 {
     return sb->s_fs_info;
 }
 static inline struct ext4_inode_info *EXT4_I(struct inode *inode)
 {
     return container_of(inode, struct ext4_inode_info, vfs_inode);
 }
 
 static inline int ext4_valid_inum(struct super_block *sb, unsigned long ino)
 {
     return ino == EXT4_ROOT_INO ||
         (ino >= EXT4_FIRST_INO(sb) &&
          ino <= le32_to_cpu(EXT4_SB(sb)->s_es->s_inodes_count));
 }
 
 /*
  * Returns: sbi->field[index]
  * Used to access an array element from the following sbi fields which require
  * rcu protection to avoid dereferencing an invalid pointer due to reassignment
  * - s_group_desc
  * - s_group_info
  * - s_flex_group
  */
 #define sbi_array_rcu_deref(sbi, field, index)                 \
 ({                                     \
     typeof(*((sbi)->field)) _v;                    \
     rcu_read_lock();                           \
     _v = ((typeof(_v)*)rcu_dereference((sbi)->field))[index];      \
     rcu_read_unlock();                         \
     _v;                                \
 })
 
 /*
  * run-time mount flags
  */
 enum {
     EXT4_MF_MNTDIR_SAMPLED,
     EXT4_MF_FS_ABORTED, /* Fatal error detected */
     EXT4_MF_FC_INELIGIBLE   /* Fast commit ineligible */
 };
 
 static inline void ext4_set_mount_flag(struct super_block *sb, int bit)
 {
     set_bit(bit, &EXT4_SB(sb)->s_mount_flags);
 }
 
 static inline void ext4_clear_mount_flag(struct super_block *sb, int bit)
 {
     clear_bit(bit, &EXT4_SB(sb)->s_mount_flags);
 }
 
 static inline int ext4_test_mount_flag(struct super_block *sb, int bit)
 {
     return test_bit(bit, &EXT4_SB(sb)->s_mount_flags);
 }
 
 
 /*
  * Simulate_fail codes
  */
 #define EXT4_SIM_BBITMAP_EIO    1
 #define EXT4_SIM_BBITMAP_CRC    2
 #define EXT4_SIM_IBITMAP_EIO    3
 #define EXT4_SIM_IBITMAP_CRC    4
 #define EXT4_SIM_INODE_EIO  5
 #define EXT4_SIM_INODE_CRC  6
 #define EXT4_SIM_DIRBLOCK_EIO   7
 #define EXT4_SIM_DIRBLOCK_CRC   8
 
 static inline bool ext4_simulate_fail(struct super_block *sb,
                      unsigned long code)
 {
 #ifdef CONFIG_EXT4_DEBUG
     struct ext4_sb_info *sbi = EXT4_SB(sb);
 
     if (unlikely(sbi->s_simulate_fail == code)) {
         sbi->s_simulate_fail = 0;
         return true;
     }
 #endif
     return false;
 }
 
 static inline void ext4_simulate_fail_bh(struct super_block *sb,
                      struct buffer_head *bh,
                      unsigned long code)
 {
     if (!IS_ERR(bh) && ext4_simulate_fail(sb, code))
         clear_buffer_uptodate(bh);
 }
 
 /*
  * Error number codes for s_{first,last}_error_errno
  *
  * Linux errno numbers are architecture specific, so we need to translate
  * them into something which is architecture independent.   We don't define
  * codes for all errno's; just the ones which are most likely to be the cause
  * of an ext4_error() call.
  */
 #define EXT4_ERR_UNKNOWN     1
 #define EXT4_ERR_EIO         2
 #define EXT4_ERR_ENOMEM      3
 #define EXT4_ERR_EFSBADCRC   4
 #define EXT4_ERR_EFSCORRUPTED    5
 #define EXT4_ERR_ENOSPC      6
 #define EXT4_ERR_ENOKEY      7
 #define EXT4_ERR_EROFS       8
 #define EXT4_ERR_EFBIG       9
 #define EXT4_ERR_EEXIST     10
 #define EXT4_ERR_ERANGE     11
 #define EXT4_ERR_EOVERFLOW  12
 #define EXT4_ERR_EBUSY      13
 #define EXT4_ERR_ENOTDIR    14
 #define EXT4_ERR_ENOTEMPTY  15
 #define EXT4_ERR_ESHUTDOWN  16
 #define EXT4_ERR_EFAULT     17
 
 /*
  * Inode dynamic state flags
  */
 enum {
     EXT4_STATE_JDATA,       /* journaled data exists */
     EXT4_STATE_NEW,         /* inode is newly created */
     EXT4_STATE_XATTR,       /* has in-inode xattrs */
     EXT4_STATE_NO_EXPAND,       /* No space for expansion */
     EXT4_STATE_DA_ALLOC_CLOSE,  /* Alloc DA blks on close */
     EXT4_STATE_EXT_MIGRATE,     /* Inode is migrating */
     EXT4_STATE_NEWENTRY,        /* File just added to dir */
     EXT4_STATE_MAY_INLINE_DATA, /* may have in-inode data */
     EXT4_STATE_EXT_PRECACHED,   /* extents have been precached */
     EXT4_STATE_LUSTRE_EA_INODE, /* Lustre-style ea_inode */
     EXT4_STATE_VERITY_IN_PROGRESS,  /* building fs-verity Merkle tree */
     EXT4_STATE_FC_COMMITTING,   /* Fast commit ongoing */
     EXT4_STATE_ORPHAN_FILE,     /* Inode orphaned in orphan file */
 };
 
 #define EXT4_INODE_BIT_FNS(name, field, offset)             \
 static inline int ext4_test_inode_##name(struct inode *inode, int bit)  \
 {                                   \
     return test_bit(bit + (offset), &EXT4_I(inode)->i_##field); \
 }                                   \
 static inline void ext4_set_inode_##name(struct inode *inode, int bit)  \
 {                                   \
     set_bit(bit + (offset), &EXT4_I(inode)->i_##field);     \
 }                                   \
 static inline void ext4_clear_inode_##name(struct inode *inode, int bit) \
 {                                   \
     clear_bit(bit + (offset), &EXT4_I(inode)->i_##field);       \
 }
 
 /* Add these declarations here only so that these functions can be
  * found by name.  Otherwise, they are very hard to locate. */
 static inline int ext4_test_inode_flag(struct inode *inode, int bit);
 static inline void ext4_set_inode_flag(struct inode *inode, int bit);
 static inline void ext4_clear_inode_flag(struct inode *inode, int bit);
 EXT4_INODE_BIT_FNS(flag, flags, 0)
 
 /* Add these declarations here only so that these functions can be
  * found by name.  Otherwise, they are very hard to locate. */
 static inline int ext4_test_inode_state(struct inode *inode, int bit);
 static inline void ext4_set_inode_state(struct inode *inode, int bit);
 static inline void ext4_clear_inode_state(struct inode *inode, int bit);
 #if (BITS_PER_LONG < 64)
 EXT4_INODE_BIT_FNS(state, state_flags, 0)
 
 static inline void ext4_clear_state_flags(struct ext4_inode_info *ei)
 {
     (ei)->i_state_flags = 0;
 }
 #else
 EXT4_INODE_BIT_FNS(state, flags, 32)
 
 static inline void ext4_clear_state_flags(struct ext4_inode_info *ei)
 {
     /* We depend on the fact that callers will set i_flags */
 }
 #endif
 #else
 /* Assume that user mode programs are passing in an ext4fs superblock, not
  * a kernel struct super_block.  This will allow us to call the feature-test
  * macros from user land. */
 #define EXT4_SB(sb) (sb)
 #endif
 
 static inline bool ext4_verity_in_progress(struct inode *inode)
 {
     return IS_ENABLED(CONFIG_FS_VERITY) &&
            ext4_test_inode_state(inode, EXT4_STATE_VERITY_IN_PROGRESS);
 }
 
 #define NEXT_ORPHAN(inode) EXT4_I(inode)->i_dtime
 
 /*
  * Codes for operating systems
  */
 #define EXT4_OS_LINUX       0
 #define EXT4_OS_HURD        1
 #define EXT4_OS_MASIX       2
 #define EXT4_OS_FREEBSD     3
 #define EXT4_OS_LITES       4
 
 /*
  * 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_MAX_SUPP_REV   EXT4_DYNAMIC_REV
 
 #define EXT4_GOOD_OLD_INODE_SIZE 128
 
 #define EXT4_EXTRA_TIMESTAMP_MAX    (((s64)1 << 34) - 1  + S32_MIN)
 #define EXT4_NON_EXTRA_TIMESTAMP_MAX    S32_MAX
 #define EXT4_TIMESTAMP_MIN      S32_MIN
 
 /*
  * Feature set definitions
  */
 
 #define EXT4_FEATURE_COMPAT_DIR_PREALLOC    0x0001
 #define EXT4_FEATURE_COMPAT_IMAGIC_INODES   0x0002
 #define EXT4_FEATURE_COMPAT_HAS_JOURNAL     0x0004
 #define EXT4_FEATURE_COMPAT_EXT_ATTR        0x0008
 #define EXT4_FEATURE_COMPAT_RESIZE_INODE    0x0010
 #define EXT4_FEATURE_COMPAT_DIR_INDEX       0x0020
 #define EXT4_FEATURE_COMPAT_SPARSE_SUPER2   0x0200
 /*
  * The reason why "FAST_COMMIT" is a compat feature is that, FS becomes
  * incompatible only if fast commit blocks are present in the FS. Since we
  * clear the journal (and thus the fast commit blocks), we don't mark FS as
  * incompatible. We also have a JBD2 incompat feature, which gets set when
  * there are fast commit blocks present in the journal.
  */
 #define EXT4_FEATURE_COMPAT_FAST_COMMIT     0x0400
 #define EXT4_FEATURE_COMPAT_STABLE_INODES   0x0800
 #define EXT4_FEATURE_COMPAT_ORPHAN_FILE     0x1000  /* Orphan file exists */
 
 #define EXT4_FEATURE_RO_COMPAT_SPARSE_SUPER 0x0001
 #define EXT4_FEATURE_RO_COMPAT_LARGE_FILE   0x0002
 #define EXT4_FEATURE_RO_COMPAT_BTREE_DIR    0x0004
 #define EXT4_FEATURE_RO_COMPAT_HUGE_FILE        0x0008
 #define EXT4_FEATURE_RO_COMPAT_GDT_CSUM     0x0010
 #define EXT4_FEATURE_RO_COMPAT_DIR_NLINK    0x0020
 #define EXT4_FEATURE_RO_COMPAT_EXTRA_ISIZE  0x0040
 #define EXT4_FEATURE_RO_COMPAT_QUOTA        0x0100
 #define EXT4_FEATURE_RO_COMPAT_BIGALLOC     0x0200
 /*
  * METADATA_CSUM also enables group descriptor checksums (GDT_CSUM).  When
  * METADATA_CSUM is set, group descriptor checksums use the same algorithm as
  * all other data structures' checksums.  However, the METADATA_CSUM and
  * GDT_CSUM bits are mutually exclusive.
  */
 #define EXT4_FEATURE_RO_COMPAT_METADATA_CSUM    0x0400
 #define EXT4_FEATURE_RO_COMPAT_READONLY     0x1000
 #define EXT4_FEATURE_RO_COMPAT_PROJECT      0x2000
 #define EXT4_FEATURE_RO_COMPAT_VERITY       0x8000
 #define EXT4_FEATURE_RO_COMPAT_ORPHAN_PRESENT   0x10000 /* Orphan file may be
                                non-empty */
 
 #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_CSUM_SEED     0x2000
 #define EXT4_FEATURE_INCOMPAT_LARGEDIR      0x4000 /* >2GB or 3-lvl htree */
 #define EXT4_FEATURE_INCOMPAT_INLINE_DATA   0x8000 /* data in inode */
 #define EXT4_FEATURE_INCOMPAT_ENCRYPT       0x10000
 #define EXT4_FEATURE_INCOMPAT_CASEFOLD      0x20000
 
 extern void ext4_update_dynamic_rev(struct super_block *sb);
 
 #define EXT4_FEATURE_COMPAT_FUNCS(name, flagname) \
 static inline bool ext4_has_feature_##name(struct super_block *sb) \
 { \
     return ((EXT4_SB(sb)->s_es->s_feature_compat & \
         cpu_to_le32(EXT4_FEATURE_COMPAT_##flagname)) != 0); \
 } \
 static inline void ext4_set_feature_##name(struct super_block *sb) \
 { \
     ext4_update_dynamic_rev(sb); \
     EXT4_SB(sb)->s_es->s_feature_compat |= \
         cpu_to_le32(EXT4_FEATURE_COMPAT_##flagname); \
 } \
 static inline void ext4_clear_feature_##name(struct super_block *sb) \
 { \
     EXT4_SB(sb)->s_es->s_feature_compat &= \
         ~cpu_to_le32(EXT4_FEATURE_COMPAT_##flagname); \
 }
 
 #define EXT4_FEATURE_RO_COMPAT_FUNCS(name, flagname) \
 static inline bool ext4_has_feature_##name(struct super_block *sb) \
 { \
     return ((EXT4_SB(sb)->s_es->s_feature_ro_compat & \
         cpu_to_le32(EXT4_FEATURE_RO_COMPAT_##flagname)) != 0); \
 } \
 static inline void ext4_set_feature_##name(struct super_block *sb) \
 { \
     ext4_update_dynamic_rev(sb); \
     EXT4_SB(sb)->s_es->s_feature_ro_compat |= \
         cpu_to_le32(EXT4_FEATURE_RO_COMPAT_##flagname); \
 } \
 static inline void ext4_clear_feature_##name(struct super_block *sb) \
 { \
     EXT4_SB(sb)->s_es->s_feature_ro_compat &= \
         ~cpu_to_le32(EXT4_FEATURE_RO_COMPAT_##flagname); \
 }
 
 #define EXT4_FEATURE_INCOMPAT_FUNCS(name, flagname) \
 static inline bool ext4_has_feature_##name(struct super_block *sb) \
 { \
     return ((EXT4_SB(sb)->s_es->s_feature_incompat & \
         cpu_to_le32(EXT4_FEATURE_INCOMPAT_##flagname)) != 0); \
 } \
 static inline void ext4_set_feature_##name(struct super_block *sb) \
 { \
     ext4_update_dynamic_rev(sb); \
     EXT4_SB(sb)->s_es->s_feature_incompat |= \
         cpu_to_le32(EXT4_FEATURE_INCOMPAT_##flagname); \
 } \
 static inline void ext4_clear_feature_##name(struct super_block *sb) \
 { \
     EXT4_SB(sb)->s_es->s_feature_incompat &= \
         ~cpu_to_le32(EXT4_FEATURE_INCOMPAT_##flagname); \
 }
 
 EXT4_FEATURE_COMPAT_FUNCS(dir_prealloc,     DIR_PREALLOC)
 EXT4_FEATURE_COMPAT_FUNCS(imagic_inodes,    IMAGIC_INODES)
 EXT4_FEATURE_COMPAT_FUNCS(journal,      HAS_JOURNAL)
 EXT4_FEATURE_COMPAT_FUNCS(xattr,        EXT_ATTR)
 EXT4_FEATURE_COMPAT_FUNCS(resize_inode,     RESIZE_INODE)
 EXT4_FEATURE_COMPAT_FUNCS(dir_index,        DIR_INDEX)
 EXT4_FEATURE_COMPAT_FUNCS(sparse_super2,    SPARSE_SUPER2)
 EXT4_FEATURE_COMPAT_FUNCS(fast_commit,      FAST_COMMIT)
 EXT4_FEATURE_COMPAT_FUNCS(stable_inodes,    STABLE_INODES)
 EXT4_FEATURE_COMPAT_FUNCS(orphan_file,      ORPHAN_FILE)
 
 EXT4_FEATURE_RO_COMPAT_FUNCS(sparse_super,  SPARSE_SUPER)
 EXT4_FEATURE_RO_COMPAT_FUNCS(large_file,    LARGE_FILE)
 EXT4_FEATURE_RO_COMPAT_FUNCS(btree_dir,     BTREE_DIR)
 EXT4_FEATURE_RO_COMPAT_FUNCS(huge_file,     HUGE_FILE)
 EXT4_FEATURE_RO_COMPAT_FUNCS(gdt_csum,      GDT_CSUM)
 EXT4_FEATURE_RO_COMPAT_FUNCS(dir_nlink,     DIR_NLINK)
 EXT4_FEATURE_RO_COMPAT_FUNCS(extra_isize,   EXTRA_ISIZE)
 EXT4_FEATURE_RO_COMPAT_FUNCS(quota,     QUOTA)
 EXT4_FEATURE_RO_COMPAT_FUNCS(bigalloc,      BIGALLOC)
 EXT4_FEATURE_RO_COMPAT_FUNCS(metadata_csum, METADATA_CSUM)
 EXT4_FEATURE_RO_COMPAT_FUNCS(readonly,      READONLY)
 EXT4_FEATURE_RO_COMPAT_FUNCS(project,       PROJECT)
 EXT4_FEATURE_RO_COMPAT_FUNCS(verity,        VERITY)
 EXT4_FEATURE_RO_COMPAT_FUNCS(orphan_present,    ORPHAN_PRESENT)
 
 EXT4_FEATURE_INCOMPAT_FUNCS(compression,    COMPRESSION)
 EXT4_FEATURE_INCOMPAT_FUNCS(filetype,       FILETYPE)
 EXT4_FEATURE_INCOMPAT_FUNCS(journal_needs_recovery, RECOVER)
 EXT4_FEATURE_INCOMPAT_FUNCS(journal_dev,    JOURNAL_DEV)
 EXT4_FEATURE_INCOMPAT_FUNCS(meta_bg,        META_BG)
 EXT4_FEATURE_INCOMPAT_FUNCS(extents,        EXTENTS)
 EXT4_FEATURE_INCOMPAT_FUNCS(64bit,      64BIT)
 EXT4_FEATURE_INCOMPAT_FUNCS(mmp,        MMP)
 EXT4_FEATURE_INCOMPAT_FUNCS(flex_bg,        FLEX_BG)
 EXT4_FEATURE_INCOMPAT_FUNCS(ea_inode,       EA_INODE)
 EXT4_FEATURE_INCOMPAT_FUNCS(dirdata,        DIRDATA)
 EXT4_FEATURE_INCOMPAT_FUNCS(csum_seed,      CSUM_SEED)
 EXT4_FEATURE_INCOMPAT_FUNCS(largedir,       LARGEDIR)
 EXT4_FEATURE_INCOMPAT_FUNCS(inline_data,    INLINE_DATA)
 EXT4_FEATURE_INCOMPAT_FUNCS(encrypt,        ENCRYPT)
 EXT4_FEATURE_INCOMPAT_FUNCS(casefold,       CASEFOLD)
 
 #define EXT2_FEATURE_COMPAT_SUPP    EXT4_FEATURE_COMPAT_EXT_ATTR
 #define EXT2_FEATURE_INCOMPAT_SUPP  (EXT4_FEATURE_INCOMPAT_FILETYPE| \
                      EXT4_FEATURE_INCOMPAT_META_BG)
 #define EXT2_FEATURE_RO_COMPAT_SUPP (EXT4_FEATURE_RO_COMPAT_SPARSE_SUPER| \
                      EXT4_FEATURE_RO_COMPAT_LARGE_FILE| \
                      EXT4_FEATURE_RO_COMPAT_BTREE_DIR)
 
 #define EXT3_FEATURE_COMPAT_SUPP    EXT4_FEATURE_COMPAT_EXT_ATTR
 #define EXT3_FEATURE_INCOMPAT_SUPP  (EXT4_FEATURE_INCOMPAT_FILETYPE| \
                      EXT4_FEATURE_INCOMPAT_RECOVER| \
                      EXT4_FEATURE_INCOMPAT_META_BG)
 #define EXT3_FEATURE_RO_COMPAT_SUPP (EXT4_FEATURE_RO_COMPAT_SPARSE_SUPER| \
                      EXT4_FEATURE_RO_COMPAT_LARGE_FILE| \
                      EXT4_FEATURE_RO_COMPAT_BTREE_DIR)
 
 #define EXT4_FEATURE_COMPAT_SUPP    (EXT4_FEATURE_COMPAT_EXT_ATTR| \
                      EXT4_FEATURE_COMPAT_ORPHAN_FILE)
 #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_EA_INODE| \
                      EXT4_FEATURE_INCOMPAT_MMP | \
                      EXT4_FEATURE_INCOMPAT_INLINE_DATA | \
                      EXT4_FEATURE_INCOMPAT_ENCRYPT | \
                      EXT4_FEATURE_INCOMPAT_CASEFOLD | \
                      EXT4_FEATURE_INCOMPAT_CSUM_SEED | \
                      EXT4_FEATURE_INCOMPAT_LARGEDIR)
 #define EXT4_FEATURE_RO_COMPAT_SUPP (EXT4_FEATURE_RO_COMPAT_SPARSE_SUPER| \
                      EXT4_FEATURE_RO_COMPAT_LARGE_FILE| \
                      EXT4_FEATURE_RO_COMPAT_GDT_CSUM| \
                      EXT4_FEATURE_RO_COMPAT_DIR_NLINK | \
                      EXT4_FEATURE_RO_COMPAT_EXTRA_ISIZE | \
                      EXT4_FEATURE_RO_COMPAT_BTREE_DIR |\
                      EXT4_FEATURE_RO_COMPAT_HUGE_FILE |\
                      EXT4_FEATURE_RO_COMPAT_BIGALLOC |\
                      EXT4_FEATURE_RO_COMPAT_METADATA_CSUM|\
                      EXT4_FEATURE_RO_COMPAT_QUOTA |\
                      EXT4_FEATURE_RO_COMPAT_PROJECT |\
                      EXT4_FEATURE_RO_COMPAT_VERITY |\
                      EXT4_FEATURE_RO_COMPAT_ORPHAN_PRESENT)
 
 #define EXTN_FEATURE_FUNCS(ver) \
 static inline bool ext4_has_unknown_ext##ver##_compat_features(struct super_block *sb) \
 { \
     return ((EXT4_SB(sb)->s_es->s_feature_compat & \
         cpu_to_le32(~EXT##ver##_FEATURE_COMPAT_SUPP)) != 0); \
 } \
 static inline bool ext4_has_unknown_ext##ver##_ro_compat_features(struct super_block *sb) \
 { \
     return ((EXT4_SB(sb)->s_es->s_feature_ro_compat & \
         cpu_to_le32(~EXT##ver##_FEATURE_RO_COMPAT_SUPP)) != 0); \
 } \
 static inline bool ext4_has_unknown_ext##ver##_incompat_features(struct super_block *sb) \
 { \
     return ((EXT4_SB(sb)->s_es->s_feature_incompat & \
         cpu_to_le32(~EXT##ver##_FEATURE_INCOMPAT_SUPP)) != 0); \
 }
 
 EXTN_FEATURE_FUNCS(2)
 EXTN_FEATURE_FUNCS(3)
 EXTN_FEATURE_FUNCS(4)
 
 static inline bool ext4_has_compat_features(struct super_block *sb)
 {
     return (EXT4_SB(sb)->s_es->s_feature_compat != 0);
 }
 static inline bool ext4_has_ro_compat_features(struct super_block *sb)
 {
     return (EXT4_SB(sb)->s_es->s_feature_ro_compat != 0);
 }
 static inline bool ext4_has_incompat_features(struct super_block *sb)
 {
     return (EXT4_SB(sb)->s_es->s_feature_incompat != 0);
 }
 
 extern int ext4_feature_set_ok(struct super_block *sb, int readonly);
 
 /*
  * Superblock flags
  */
 #define EXT4_FLAGS_RESIZING 0
 #define EXT4_FLAGS_SHUTDOWN 1
 #define EXT4_FLAGS_BDEV_IS_DAX  2
 
 static inline int ext4_forced_shutdown(struct ext4_sb_info *sbi)
 {
     return test_bit(EXT4_FLAGS_SHUTDOWN, &sbi->s_ext4_flags);
 }
 
 /*
  * Default values for user and/or group using reserved blocks
  */
 #define EXT4_DEF_RESUID     0
 #define EXT4_DEF_RESGID     0
 
 /*
  * Default project ID
  */
 #define EXT4_DEF_PROJID     0
 
 #define EXT4_DEF_INODE_READAHEAD_BLKS   32
 
 /*
  * Default mount options
  */
 #define EXT4_DEFM_DEBUG     0x0001
 #define EXT4_DEFM_BSDGROUPS 0x0002
 #define EXT4_DEFM_XATTR_USER    0x0004
 #define EXT4_DEFM_ACL       0x0008
 #define EXT4_DEFM_UID16     0x0010
 #define EXT4_DEFM_JMODE     0x0060
 #define EXT4_DEFM_JMODE_DATA    0x0020
 #define EXT4_DEFM_JMODE_ORDERED 0x0040
 #define EXT4_DEFM_JMODE_WBACK   0x0060
 #define EXT4_DEFM_NOBARRIER 0x0100
 #define EXT4_DEFM_BLOCK_VALIDITY 0x0200
 #define EXT4_DEFM_DISCARD   0x0400
 #define EXT4_DEFM_NODELALLOC    0x0800
 
 /*
  * Default journal batch times
  */
 #define EXT4_DEF_MIN_BATCH_TIME 0
 #define EXT4_DEF_MAX_BATCH_TIME 15000 /* 15ms */
 
 /*
  * Minimum number of groups in a flexgroup before we separate out
  * directories into the first block group of a flexgroup
  */
 #define EXT4_FLEX_SIZE_DIR_ALLOC_SCHEME 4
 
 /*
  * Structure of a directory entry
  */
 #define EXT4_NAME_LEN 255
 /*
  * Base length of the ext4 directory entry excluding the name length
  */
 #define EXT4_BASE_DIR_LEN (sizeof(struct ext4_dir_entry_2) - EXT4_NAME_LEN)
 
 struct ext4_dir_entry {
     __le32  inode;          /* Inode number */
     __le16  rec_len;        /* Directory entry length */
     __le16  name_len;       /* Name length */
     char    name[EXT4_NAME_LEN];    /* File name */
 };
 
 
 /*
  * Encrypted Casefolded entries require saving the hash on disk. This structure
  * followed ext4_dir_entry_2's name[name_len] at the next 4 byte aligned
  * boundary.
  */
 struct ext4_dir_entry_hash {
     __le32 hash;
     __le32 minor_hash;
 };
 
 /*
  * The new version of the directory entry.  Since EXT4 structures are
  * stored in intel byte order, and the name_len field could never be
  * bigger than 255 chars, it's safe to reclaim the extra byte for the
  * file_type field.
  */
 struct ext4_dir_entry_2 {
     __le32  inode;          /* Inode number */
     __le16  rec_len;        /* Directory entry length */
     __u8    name_len;       /* Name length */
     __u8    file_type;      /* See file type macros EXT4_FT_* below */
     char    name[EXT4_NAME_LEN];    /* File name */
 };
 
 /*
  * Access the hashes at the end of ext4_dir_entry_2
  */
 #define EXT4_DIRENT_HASHES(entry) \
     ((struct ext4_dir_entry_hash *) \
         (((void *)(entry)) + \
         ((8 + (entry)->name_len + EXT4_DIR_ROUND) & ~EXT4_DIR_ROUND)))
 #define EXT4_DIRENT_HASH(entry) le32_to_cpu(EXT4_DIRENT_HASHES(de)->hash)
 #define EXT4_DIRENT_MINOR_HASH(entry) \
         le32_to_cpu(EXT4_DIRENT_HASHES(de)->minor_hash)
 
 static inline bool ext4_hash_in_dirent(const struct inode *inode)
 {
     return IS_CASEFOLDED(inode) && IS_ENCRYPTED(inode);
 }
 
 /*
  * This is a bogus directory entry at the end of each leaf block that
  * records checksums.
  */
 struct ext4_dir_entry_tail {
     __le32  det_reserved_zero1; /* Pretend to be unused */
     __le16  det_rec_len;        /* 12 */
     __u8    det_reserved_zero2; /* Zero name length */
     __u8    det_reserved_ft;    /* 0xDE, fake file type */
     __le32  det_checksum;       /* crc32c(uuid+inum+dirblock) */
 };
 
 #define EXT4_DIRENT_TAIL(block, blocksize) \
     ((struct ext4_dir_entry_tail *)(((void *)(block)) + \
                     ((blocksize) - \
                      sizeof(struct ext4_dir_entry_tail))))
 
 /*
  * Ext4 directory file types.  Only the low 3 bits are used.  The
  * other bits are reserved for now.
  */
 #define EXT4_FT_UNKNOWN     0
 #define EXT4_FT_REG_FILE    1
 #define EXT4_FT_DIR     2
 #define EXT4_FT_CHRDEV      3
 #define EXT4_FT_BLKDEV      4
 #define EXT4_FT_FIFO        5
 #define EXT4_FT_SOCK        6
 #define EXT4_FT_SYMLINK     7
 
 #define EXT4_FT_MAX     8
 
 #define EXT4_FT_DIR_CSUM    0xDE
 
 /*
  * EXT4_DIR_PAD defines the directory entries boundaries
  *
  * NOTE: It must be a multiple of 4
  */
 #define EXT4_DIR_PAD            4
 #define EXT4_DIR_ROUND          (EXT4_DIR_PAD - 1)
 #define EXT4_MAX_REC_LEN        ((1<<16)-1)
 
 /*
  * The rec_len is dependent on the type of directory. Directories that are
  * casefolded and encrypted need to store the hash as well, so we add room for
  * ext4_extended_dir_entry_2. For all entries related to '.' or '..' you should
  * pass NULL for dir, as those entries do not use the extra fields.
  */
 static inline unsigned int ext4_dir_rec_len(__u8 name_len,
                         const struct inode *dir)
 {
     int rec_len = (name_len + 8 + EXT4_DIR_ROUND);
 
     if (dir && ext4_hash_in_dirent(dir))
         rec_len += sizeof(struct ext4_dir_entry_hash);
     return (rec_len & ~EXT4_DIR_ROUND);
 }
 
 /*
  * If we ever get support for fs block sizes > page_size, we'll need
  * to remove the #if statements in the next two functions...
  */
 static inline unsigned int
 ext4_rec_len_from_disk(__le16 dlen, unsigned blocksize)
 {
     unsigned len = le16_to_cpu(dlen);
 
 #if (PAGE_SIZE >= 65536)
     if (len == EXT4_MAX_REC_LEN || len == 0)
         return blocksize;
     return (len & 65532) | ((len & 3) << 16);
 #else
     return len;
 #endif
 }
 
 static inline __le16 ext4_rec_len_to_disk(unsigned len, unsigned blocksize)
 {
     BUG_ON((len > blocksize) || (blocksize > (1 << 18)) || (len & 3));
 #if (PAGE_SIZE >= 65536)
     if (len < 65536)
         return cpu_to_le16(len);
     if (len == blocksize) {
         if (blocksize == 65536)
             return cpu_to_le16(EXT4_MAX_REC_LEN);
         else
             return cpu_to_le16(0);
     }
     return cpu_to_le16((len & 65532) | ((len >> 16) & 3));
 #else
     return cpu_to_le16(len);
 #endif
 }
 
 /*
  * Hash Tree Directory indexing
  * (c) Daniel Phillips, 2001
  */
 
 #define is_dx(dir) (ext4_has_feature_dir_index((dir)->i_sb) && \
             ext4_test_inode_flag((dir), EXT4_INODE_INDEX))
 #define EXT4_DIR_LINK_MAX(dir) unlikely((dir)->i_nlink >= EXT4_LINK_MAX && \
             !(ext4_has_feature_dir_nlink((dir)->i_sb) && is_dx(dir)))
 #define EXT4_DIR_LINK_EMPTY(dir) ((dir)->i_nlink == 2 || (dir)->i_nlink == 1)
 
 /* Legal values for the dx_root hash_version field: */
 
 #define DX_HASH_LEGACY          0
 #define DX_HASH_HALF_MD4        1
 #define DX_HASH_TEA         2
 #define DX_HASH_LEGACY_UNSIGNED     3
 #define DX_HASH_HALF_MD4_UNSIGNED   4
 #define DX_HASH_TEA_UNSIGNED        5
 #define DX_HASH_SIPHASH         6
 
 static inline u32 ext4_chksum(struct ext4_sb_info *sbi, u32 crc,
                   const void *address, unsigned int length)
 {
     struct {
         struct shash_desc shash;
         char ctx[4];
     } desc;
 
     BUG_ON(crypto_shash_descsize(sbi->s_chksum_driver)!=sizeof(desc.ctx));
 
     desc.shash.tfm = sbi->s_chksum_driver;
     *(u32 *)desc.ctx = crc;
 
     BUG_ON(crypto_shash_update(&desc.shash, address, length));
 
     return *(u32 *)desc.ctx;
 }
 
 #ifdef __KERNEL__
 
 /* hash info structure used by the directory hash */
 struct dx_hash_info
 {
     u32     hash;
     u32     minor_hash;
     int     hash_version;
     u32     *seed;
 };
 
 
 /* 32 and 64 bit signed EOF for dx directories */
 #define EXT4_HTREE_EOF_32BIT   ((1UL  << (32 - 1)) - 1)
 #define EXT4_HTREE_EOF_64BIT   ((1ULL << (64 - 1)) - 1)
 
 
 /*
  * Control parameters used by ext4_htree_next_block
  */
 #define HASH_NB_ALWAYS      1
 
 struct ext4_filename {
     const struct qstr *usr_fname;
     struct fscrypt_str disk_name;
     struct dx_hash_info hinfo;
 #ifdef CONFIG_FS_ENCRYPTION
     struct fscrypt_str crypto_buf;
 #endif
 #if IS_ENABLED(CONFIG_UNICODE)
     struct fscrypt_str cf_name;
 #endif
 };
 
 #define fname_name(p) ((p)->disk_name.name)
 #define fname_usr_name(p) ((p)->usr_fname->name)
 #define fname_len(p)  ((p)->disk_name.len)
 
 /*
  * Describe an inode's exact location on disk and in memory
  */
 struct ext4_iloc
 {
     struct buffer_head *bh;
     unsigned long offset;
     ext4_group_t block_group;
 };
 
 static inline struct ext4_inode *ext4_raw_inode(struct ext4_iloc *iloc)
 {
     return (struct ext4_inode *) (iloc->bh->b_data + iloc->offset);
 }
 
 static inline bool ext4_is_quota_file(struct inode *inode)
 {
     return IS_NOQUOTA(inode) &&
            !(EXT4_I(inode)->i_flags & EXT4_EA_INODE_FL);
 }
 
 /*
  * This structure is stuffed into the struct file's private_data field
  * for directories.  It is where we put information so that we can do
  * readdir operations in hash tree order.
  */
 struct dir_private_info {
     struct rb_root  root;
     struct rb_node  *curr_node;
     struct fname    *extra_fname;
     loff_t      last_pos;
     __u32       curr_hash;
     __u32       curr_minor_hash;
     __u32       next_hash;
 };
 
 /* calculate the first block number of the group */
 static inline ext4_fsblk_t
 ext4_group_first_block_no(struct super_block *sb, ext4_group_t group_no)
 {
     return group_no * (ext4_fsblk_t)EXT4_BLOCKS_PER_GROUP(sb) +
         le32_to_cpu(EXT4_SB(sb)->s_es->s_first_data_block);
 }
 
 /*
  * Special error return code only used by dx_probe() and its callers.
  */
 #define ERR_BAD_DX_DIR  (-(MAX_ERRNO - 1))
 
 /* htree levels for ext4 */
 #define EXT4_HTREE_LEVEL_COMPAT 2
 #define EXT4_HTREE_LEVEL    3
 
 static inline int ext4_dir_htree_level(struct super_block *sb)
 {
     return ext4_has_feature_largedir(sb) ?
         EXT4_HTREE_LEVEL : EXT4_HTREE_LEVEL_COMPAT;
 }
 
 /*
  * Timeout and state flag for lazy initialization inode thread.
  */
 #define EXT4_DEF_LI_WAIT_MULT           10
 #define EXT4_DEF_LI_MAX_START_DELAY     5
 #define EXT4_LAZYINIT_QUIT          0x0001
 #define EXT4_LAZYINIT_RUNNING           0x0002
 
 /*
  * Lazy inode table initialization info
  */
 struct ext4_lazy_init {
     unsigned long       li_state;
     struct list_head    li_request_list;
     struct mutex        li_list_mtx;
 };
 
 enum ext4_li_mode {
     EXT4_LI_MODE_PREFETCH_BBITMAP,
     EXT4_LI_MODE_ITABLE,
 };
 
 struct ext4_li_request {
     struct super_block  *lr_super;
     enum ext4_li_mode   lr_mode;
     ext4_group_t        lr_first_not_zeroed;
     ext4_group_t        lr_next_group;
     struct list_head    lr_request;
     unsigned long       lr_next_sched;
     unsigned long       lr_timeout;
 };
 
 struct ext4_features {
     struct kobject f_kobj;
     struct completion f_kobj_unregister;
 };
 
 /*
  * This structure will be used for multiple mount protection. It will be
  * written into the block number saved in the s_mmp_block field in the
  * superblock. Programs that check MMP should assume that if
  * SEQ_FSCK (or any unknown code above SEQ_MAX) is present then it is NOT safe
  * to use the filesystem, regardless of how old the timestamp is.
  */
 #define EXT4_MMP_MAGIC     0x004D4D50U /* ASCII for MMP */
 #define EXT4_MMP_SEQ_CLEAN 0xFF4D4D50U /* mmp_seq value for clean unmount */
 #define EXT4_MMP_SEQ_FSCK  0xE24D4D50U /* mmp_seq value when being fscked */
 #define EXT4_MMP_SEQ_MAX   0xE24D4D4FU /* maximum valid mmp_seq value */
 
 struct mmp_struct {
     __le32  mmp_magic;      /* Magic number for MMP */
     __le32  mmp_seq;        /* Sequence no. updated periodically */
 
     /*
      * mmp_time, mmp_nodename & mmp_bdevname are only used for information
      * purposes and do not affect the correctness of the algorithm
      */
     __le64  mmp_time;       /* Time last updated */
     char    mmp_nodename[64];   /* Node which last updated MMP block */
     char    mmp_bdevname[32];   /* Bdev which last updated MMP block */
 
     /*
      * mmp_check_interval is used to verify if the MMP block has been
      * updated on the block device. The value is updated based on the
      * maximum time to write the MMP block during an update cycle.
      */
     __le16  mmp_check_interval;
 
     __le16  mmp_pad1;
     __le32  mmp_pad2[226];
     __le32  mmp_checksum;       /* crc32c(uuid+mmp_block) */
 };
 
 /* arguments passed to the mmp thread */
 struct mmpd_data {
     struct buffer_head *bh; /* bh from initial read_mmp_block() */
     struct super_block *sb;  /* super block of the fs */
 };
 
 /*
  * Check interval multiplier
  * The MMP block is written every update interval and initially checked every
  * update interval x the multiplier (the value is then adapted based on the
  * write latency). The reason is that writes can be delayed under load and we
  * don't want readers to incorrectly assume that the filesystem is no longer
  * in use.
  */
 #define EXT4_MMP_CHECK_MULT     2UL
 
 /*
  * Minimum interval for MMP checking in seconds.
  */
 #define EXT4_MMP_MIN_CHECK_INTERVAL 5UL
 
 /*
  * Maximum interval for MMP checking in seconds.
  */
 #define EXT4_MMP_MAX_CHECK_INTERVAL 300UL
 
 /*
  * Function prototypes
  */
 
 /*
  * Ok, these declarations are also in <linux/kernel.h> but none of the
  * ext4 source programs needs to include it so they are duplicated here.
  */
 # define NORET_TYPE /**/
 # define ATTRIB_NORET   __attribute__((noreturn))
 # define NORET_AND  noreturn,
 
 /* bitmap.c */
 extern unsigned int ext4_count_free(char *bitmap, unsigned numchars);
 void ext4_inode_bitmap_csum_set(struct super_block *sb, ext4_group_t group,
                 struct ext4_group_desc *gdp,
                 struct buffer_head *bh, int sz);
 int ext4_inode_bitmap_csum_verify(struct super_block *sb, ext4_group_t group,
                   struct ext4_group_desc *gdp,
                   struct buffer_head *bh, int sz);
 void ext4_block_bitmap_csum_set(struct super_block *sb, ext4_group_t group,
                 struct ext4_group_desc *gdp,
                 struct buffer_head *bh);
 int ext4_block_bitmap_csum_verify(struct super_block *sb, ext4_group_t group,
                   struct ext4_group_desc *gdp,
                   struct buffer_head *bh);
 
 /* balloc.c */
 extern void ext4_get_group_no_and_offset(struct super_block *sb,
                      ext4_fsblk_t blocknr,
                      ext4_group_t *blockgrpp,
                      ext4_grpblk_t *offsetp);
 extern ext4_group_t ext4_get_group_number(struct super_block *sb,
                       ext4_fsblk_t block);
 
 extern unsigned int ext4_block_group(struct super_block *sb,
             ext4_fsblk_t blocknr);
 extern ext4_grpblk_t ext4_block_group_offset(struct super_block *sb,
             ext4_fsblk_t blocknr);
 extern int ext4_bg_has_super(struct super_block *sb, ext4_group_t group);
 extern unsigned long ext4_bg_num_gdb(struct super_block *sb,
             ext4_group_t group);
 extern ext4_fsblk_t ext4_new_meta_blocks(handle_t *handle, struct inode *inode,
                      ext4_fsblk_t goal,
                      unsigned int flags,
                      unsigned long *count,
                      int *errp);
 extern int ext4_claim_free_clusters(struct ext4_sb_info *sbi,
                     s64 nclusters, unsigned int flags);
 extern ext4_fsblk_t ext4_count_free_clusters(struct super_block *);
 extern void ext4_check_blocks_bitmap(struct super_block *);
 extern struct ext4_group_desc * ext4_get_group_desc(struct super_block * sb,
                             ext4_group_t block_group,
                             struct buffer_head ** bh);
 extern int ext4_should_retry_alloc(struct super_block *sb, int *retries);
 
 extern struct buffer_head *ext4_read_block_bitmap_nowait(struct super_block *sb,
                         ext4_group_t block_group,
                         bool ignore_locked);
 extern int ext4_wait_block_bitmap(struct super_block *sb,
                   ext4_group_t block_group,
                   struct buffer_head *bh);
 extern struct buffer_head *ext4_read_block_bitmap(struct super_block *sb,
                           ext4_group_t block_group);
 extern unsigned ext4_free_clusters_after_init(struct super_block *sb,
                           ext4_group_t block_group,
                           struct ext4_group_desc *gdp);
 ext4_fsblk_t ext4_inode_to_goal_block(struct inode *);
 
 #if IS_ENABLED(CONFIG_UNICODE)
 extern int ext4_fname_setup_ci_filename(struct inode *dir,
                      const struct qstr *iname,
                      struct ext4_filename *fname);
 #endif
 
 /* ext4 encryption related stuff goes here crypto.c */
 #ifdef CONFIG_FS_ENCRYPTION
 extern const struct fscrypt_operations ext4_cryptops;
 
 int ext4_fname_setup_filename(struct inode *dir, const struct qstr *iname,
                   int lookup, struct ext4_filename *fname);
 
 int ext4_fname_prepare_lookup(struct inode *dir, struct dentry *dentry,
                   struct ext4_filename *fname);
 
 void ext4_fname_free_filename(struct ext4_filename *fname);
 
 int ext4_ioctl_get_encryption_pwsalt(struct file *filp, void __user *arg);
 
 #else /* !CONFIG_FS_ENCRYPTION */
 static inline int ext4_fname_setup_filename(struct inode *dir,
                         const struct qstr *iname,
                         int lookup,
                         struct ext4_filename *fname)
 {
     int err = 0;
     fname->usr_fname = iname;
     fname->disk_name.name = (unsigned char *) iname->name;
     fname->disk_name.len = iname->len;
 
 #if IS_ENABLED(CONFIG_UNICODE)
     err = ext4_fname_setup_ci_filename(dir, iname, fname);
 #endif
 
     return err;
 }
 
 static inline int ext4_fname_prepare_lookup(struct inode *dir,
                         struct dentry *dentry,
                         struct ext4_filename *fname)
 {
     return ext4_fname_setup_filename(dir, &dentry->d_name, 1, fname);
 }
 
 static inline void ext4_fname_free_filename(struct ext4_filename *fname)
 {
 #if IS_ENABLED(CONFIG_UNICODE)
     kfree(fname->cf_name.name);
     fname->cf_name.name = NULL;
 #endif
 }
 
 static inline int ext4_ioctl_get_encryption_pwsalt(struct file *filp,
                            void __user *arg)
 {
     return -EOPNOTSUPP;
 }
 #endif /* !CONFIG_FS_ENCRYPTION */
 
 /* dir.c */
 extern int __ext4_check_dir_entry(const char *, unsigned int, struct inode *,
                   struct file *,
                   struct ext4_dir_entry_2 *,
                   struct buffer_head *, char *, int,
                   unsigned int);
 #define ext4_check_dir_entry(dir, filp, de, bh, buf, size, offset) \
     unlikely(__ext4_check_dir_entry(__func__, __LINE__, (dir), (filp), \
                 (de), (bh), (buf), (size), (offset)))
 extern int ext4_htree_store_dirent(struct file *dir_file, __u32 hash,
                 __u32 minor_hash,
                 struct ext4_dir_entry_2 *dirent,
                 struct fscrypt_str *ent_name);
 extern void ext4_htree_free_dir_info(struct dir_private_info *p);
 extern int ext4_find_dest_de(struct inode *dir, struct inode *inode,
                  struct buffer_head *bh,
                  void *buf, int buf_size,
                  struct ext4_filename *fname,
                  struct ext4_dir_entry_2 **dest_de);
 void ext4_insert_dentry(struct inode *dir, struct inode *inode,
             struct ext4_dir_entry_2 *de,
             int buf_size,
             struct ext4_filename *fname);
 static inline void ext4_update_dx_flag(struct inode *inode)
 {
     if (!ext4_has_feature_dir_index(inode->i_sb) &&
         ext4_test_inode_flag(inode, EXT4_INODE_INDEX)) {
         /* ext4_iget() should have caught this... */
         WARN_ON_ONCE(ext4_has_feature_metadata_csum(inode->i_sb));
         ext4_clear_inode_flag(inode, EXT4_INODE_INDEX);
     }
 }
 static const unsigned char ext4_filetype_table[] = {
     DT_UNKNOWN, DT_REG, DT_DIR, DT_CHR, DT_BLK, DT_FIFO, DT_SOCK, DT_LNK
 };
 
 static inline  unsigned char get_dtype(struct super_block *sb, int filetype)
 {
     if (!ext4_has_feature_filetype(sb) || filetype >= EXT4_FT_MAX)
         return DT_UNKNOWN;
 
     return ext4_filetype_table[filetype];
 }
 extern int ext4_check_all_de(struct inode *dir, struct buffer_head *bh,
                  void *buf, int buf_size);
 
 /* fsync.c */
 extern int ext4_sync_file(struct file *, loff_t, loff_t, int);
 
 /* hash.c */
 extern int ext4fs_dirhash(const struct inode *dir, const char *name, int len,
               struct dx_hash_info *hinfo);
 
 /* ialloc.c */
 extern int ext4_mark_inode_used(struct super_block *sb, int ino);
 extern struct inode *__ext4_new_inode(struct user_namespace *, handle_t *,
                       struct inode *, umode_t,
                       const struct qstr *qstr, __u32 goal,
                       uid_t *owner, __u32 i_flags,
                       int handle_type, unsigned int line_no,
                       int nblocks);
 
 #define ext4_new_inode(handle, dir, mode, qstr, goal, owner, i_flags)          \
     __ext4_new_inode(&init_user_ns, (handle), (dir), (mode), (qstr),       \
              (goal), (owner), i_flags, 0, 0, 0)
 #define ext4_new_inode_start_handle(mnt_userns, dir, mode, qstr, goal, owner, \
                     type, nblocks)          \
     __ext4_new_inode((mnt_userns), NULL, (dir), (mode), (qstr), (goal), (owner), \
              0, (type), __LINE__, (nblocks))
 
 
 extern void ext4_free_inode(handle_t *, struct inode *);
 extern struct inode * ext4_orphan_get(struct super_block *, unsigned long);
 extern unsigned long ext4_count_free_inodes(struct super_block *);
 extern unsigned long ext4_count_dirs(struct super_block *);
 extern void ext4_check_inodes_bitmap(struct super_block *);
 extern void ext4_mark_bitmap_end(int start_bit, int end_bit, char *bitmap);
 extern int ext4_init_inode_table(struct super_block *sb,
                  ext4_group_t group, int barrier);
 extern void ext4_end_bitmap_read(struct buffer_head *bh, int uptodate);
 
 /* fast_commit.c */
 int ext4_fc_info_show(struct seq_file *seq, void *v);
 void ext4_fc_init(struct super_block *sb, journal_t *journal);
 void ext4_fc_init_inode(struct inode *inode);
 void ext4_fc_track_range(handle_t *handle, struct inode *inode, ext4_lblk_t start,
              ext4_lblk_t end);
 void __ext4_fc_track_unlink(handle_t *handle, struct inode *inode,
     struct dentry *dentry);
 void __ext4_fc_track_link(handle_t *handle, struct inode *inode,
     struct dentry *dentry);
 void ext4_fc_track_unlink(handle_t *handle, struct dentry *dentry);
 void ext4_fc_track_link(handle_t *handle, struct dentry *dentry);
 void __ext4_fc_track_create(handle_t *handle, struct inode *inode,
                 struct dentry *dentry);
 void ext4_fc_track_create(handle_t *handle, struct dentry *dentry);
 void ext4_fc_track_inode(handle_t *handle, struct inode *inode);
 void ext4_fc_mark_ineligible(struct super_block *sb, int reason, handle_t *handle);
 void ext4_fc_start_update(struct inode *inode);
 void ext4_fc_stop_update(struct inode *inode);
 void ext4_fc_del(struct inode *inode);
 bool ext4_fc_replay_check_excluded(struct super_block *sb, ext4_fsblk_t block);
 void ext4_fc_replay_cleanup(struct super_block *sb);
 int ext4_fc_commit(journal_t *journal, tid_t commit_tid);
 int __init ext4_fc_init_dentry_cache(void);
 void ext4_fc_destroy_dentry_cache(void);
 int ext4_fc_record_regions(struct super_block *sb, int ino,
                ext4_lblk_t lblk, ext4_fsblk_t pblk,
                int len, int replay);
 
 /* mballoc.c */
 extern const struct seq_operations ext4_mb_seq_groups_ops;
 extern const struct seq_operations ext4_mb_seq_structs_summary_ops;
 extern long ext4_mb_stats;
 extern long ext4_mb_max_to_scan;
 extern int ext4_seq_mb_stats_show(struct seq_file *seq, void *offset);
 extern int ext4_mb_init(struct super_block *);
 extern int ext4_mb_release(struct super_block *);
 extern ext4_fsblk_t ext4_mb_new_blocks(handle_t *,
                 struct ext4_allocation_request *, int *);
 extern int ext4_mb_reserve_blocks(struct super_block *, int);
 extern void ext4_discard_preallocations(struct inode *, unsigned int);
 extern int __init ext4_init_mballoc(void);
 extern void ext4_exit_mballoc(void);
 extern ext4_group_t ext4_mb_prefetch(struct super_block *sb,
                      ext4_group_t group,
                      unsigned int nr, int *cnt);
 extern void ext4_mb_prefetch_fini(struct super_block *sb, ext4_group_t group,
                   unsigned int nr);
 
 extern void ext4_free_blocks(handle_t *handle, struct inode *inode,
                  struct buffer_head *bh, ext4_fsblk_t block,
                  unsigned long count, int flags);
 extern int ext4_mb_alloc_groupinfo(struct super_block *sb,
                    ext4_group_t ngroups);
 extern int ext4_mb_add_groupinfo(struct super_block *sb,
         ext4_group_t i, struct ext4_group_desc *desc);
 extern int ext4_group_add_blocks(handle_t *handle, struct super_block *sb,
                 ext4_fsblk_t block, unsigned long count);
 extern int ext4_trim_fs(struct super_block *, struct fstrim_range *);
 extern void ext4_process_freed_data(struct super_block *sb, tid_t commit_tid);
 extern void ext4_mb_mark_bb(struct super_block *sb, ext4_fsblk_t block,
                int len, int state);
 
 /* inode.c */
 void ext4_inode_csum_set(struct inode *inode, struct ext4_inode *raw,
              struct ext4_inode_info *ei);
 int ext4_inode_is_fast_symlink(struct inode *inode);
 struct buffer_head *ext4_getblk(handle_t *, struct inode *, ext4_lblk_t, int);
 struct buffer_head *ext4_bread(handle_t *, struct inode *, ext4_lblk_t, int);
 int ext4_bread_batch(struct inode *inode, ext4_lblk_t block, int bh_count,
              bool wait, struct buffer_head **bhs);
 int ext4_get_block_unwritten(struct inode *inode, sector_t iblock,
                  struct buffer_head *bh_result, int create);
 int ext4_get_block(struct inode *inode, sector_t iblock,
            struct buffer_head *bh_result, int create);
 int ext4_da_get_block_prep(struct inode *inode, sector_t iblock,
                struct buffer_head *bh, int create);
 int ext4_walk_page_buffers(handle_t *handle,
                struct inode *inode,
                struct buffer_head *head,
                unsigned from,
                unsigned to,
                int *partial,
                int (*fn)(handle_t *handle, struct inode *inode,
                      struct buffer_head *bh));
 int do_journal_get_write_access(handle_t *handle, struct inode *inode,
                 struct buffer_head *bh);
 #define FALL_BACK_TO_NONDELALLOC 1
 #define CONVERT_INLINE_DATA  2
 
 typedef enum {
     EXT4_IGET_NORMAL =  0,
     EXT4_IGET_SPECIAL = 0x0001, /* OK to iget a system inode */
     EXT4_IGET_HANDLE =  0x0002  /* Inode # is from a handle */
 } ext4_iget_flags;
 
 extern struct inode *__ext4_iget(struct super_block *sb, unsigned long ino,
                  ext4_iget_flags flags, const char *function,
                  unsigned int line);
 
 #define ext4_iget(sb, ino, flags) \
     __ext4_iget((sb), (ino), (flags), __func__, __LINE__)
 
 extern int  ext4_write_inode(struct inode *, struct writeback_control *);
 extern int  ext4_setattr(struct user_namespace *, struct dentry *,
              struct iattr *);
 extern int  ext4_getattr(struct user_namespace *, const struct path *,
              struct kstat *, u32, unsigned int);
 extern void ext4_evict_inode(struct inode *);
 extern void ext4_clear_inode(struct inode *);
 extern int  ext4_file_getattr(struct user_namespace *, const struct path *,
                   struct kstat *, u32, unsigned int);
 extern int  ext4_sync_inode(handle_t *, struct inode *);
 extern void ext4_dirty_inode(struct inode *, int);
 extern int ext4_change_inode_journal_flag(struct inode *, int);
 extern int ext4_get_inode_loc(struct inode *, struct ext4_iloc *);
 extern int ext4_get_fc_inode_loc(struct super_block *sb, unsigned long ino,
               struct ext4_iloc *iloc);
 extern int ext4_inode_attach_jinode(struct inode *inode);
 extern int ext4_can_truncate(struct inode *inode);
 extern int ext4_truncate(struct inode *);
 extern int ext4_break_layouts(struct inode *);
 extern int ext4_punch_hole(struct file *file, loff_t offset, loff_t length);
 extern void ext4_set_inode_flags(struct inode *, bool init);
 extern int ext4_alloc_da_blocks(struct inode *inode);
 extern void ext4_set_aops(struct inode *inode);
 extern int ext4_writepage_trans_blocks(struct inode *);
 extern int ext4_chunk_trans_blocks(struct inode *, int nrblocks);
 extern int ext4_zero_partial_blocks(handle_t *handle, struct inode *inode,
                  loff_t lstart, loff_t lend);
 extern vm_fault_t ext4_page_mkwrite(struct vm_fault *vmf);
 extern qsize_t *ext4_get_reserved_space(struct inode *inode);
 extern int ext4_get_projid(struct inode *inode, kprojid_t *projid);
 extern void ext4_da_release_space(struct inode *inode, int to_free);
 extern void ext4_da_update_reserve_space(struct inode *inode,
                     int used, int quota_claim);
 extern int ext4_issue_zeroout(struct inode *inode, ext4_lblk_t lblk,
                   ext4_fsblk_t pblk, ext4_lblk_t len);
 
 /* indirect.c */
 extern int ext4_ind_map_blocks(handle_t *handle, struct inode *inode,
                 struct ext4_map_blocks *map, int flags);
 extern int ext4_ind_trans_blocks(struct inode *inode, int nrblocks);
 extern void ext4_ind_truncate(handle_t *, struct inode *inode);
 extern int ext4_ind_remove_space(handle_t *handle, struct inode *inode,
                  ext4_lblk_t start, ext4_lblk_t end);
 
 /* ioctl.c */
 extern long ext4_ioctl(struct file *, unsigned int, unsigned long);
 extern long ext4_compat_ioctl(struct file *, unsigned int, unsigned long);
 int ext4_fileattr_set(struct user_namespace *mnt_userns,
               struct dentry *dentry, struct fileattr *fa);
 int ext4_fileattr_get(struct dentry *dentry, struct fileattr *fa);
 extern void ext4_reset_inode_seed(struct inode *inode);
 int ext4_update_overhead(struct super_block *sb, bool force);
 
 /* migrate.c */
 extern int ext4_ext_migrate(struct inode *);
 extern int ext4_ind_migrate(struct inode *inode);
 
 /* namei.c */
 extern int ext4_init_new_dir(handle_t *handle, struct inode *dir,
                  struct inode *inode);
 extern int ext4_dirblock_csum_verify(struct inode *inode,
                      struct buffer_head *bh);
 extern int ext4_htree_fill_tree(struct file *dir_file, __u32 start_hash,
                 __u32 start_minor_hash, __u32 *next_hash);
 extern int ext4_search_dir(struct buffer_head *bh,
                char *search_buf,
                int buf_size,
                struct inode *dir,
                struct ext4_filename *fname,
                unsigned int offset,
                struct ext4_dir_entry_2 **res_dir);
 extern int ext4_generic_delete_entry(struct inode *dir,
                      struct ext4_dir_entry_2 *de_del,
                      struct buffer_head *bh,
                      void *entry_buf,
                      int buf_size,
                      int csum_size);
 extern bool ext4_empty_dir(struct inode *inode);
 
 /* resize.c */
 extern void ext4_kvfree_array_rcu(void *to_free);
 extern int ext4_group_add(struct super_block *sb,
                 struct ext4_new_group_data *input);
 extern int ext4_group_extend(struct super_block *sb,
                 struct ext4_super_block *es,
                 ext4_fsblk_t n_blocks_count);
 extern int ext4_resize_fs(struct super_block *sb, ext4_fsblk_t n_blocks_count);
 extern unsigned int ext4_list_backups(struct super_block *sb,
                       unsigned int *three, unsigned int *five,
                       unsigned int *seven);
 
 /* super.c */
 extern struct buffer_head *ext4_sb_bread(struct super_block *sb,
                      sector_t block, blk_opf_t op_flags);
 extern struct buffer_head *ext4_sb_bread_unmovable(struct super_block *sb,
                            sector_t block);
 extern void ext4_read_bh_nowait(struct buffer_head *bh, blk_opf_t op_flags,
                 bh_end_io_t *end_io);
 extern int ext4_read_bh(struct buffer_head *bh, blk_opf_t op_flags,
             bh_end_io_t *end_io);
 extern int ext4_read_bh_lock(struct buffer_head *bh, blk_opf_t op_flags, bool wait);
 extern void ext4_sb_breadahead_unmovable(struct super_block *sb, sector_t block);
 extern int ext4_seq_options_show(struct seq_file *seq, void *offset);
 extern int ext4_calculate_overhead(struct super_block *sb);
 extern __le32 ext4_superblock_csum(struct super_block *sb,
                    struct ext4_super_block *es);
 extern void ext4_superblock_csum_set(struct super_block *sb);
 extern int ext4_alloc_flex_bg_array(struct super_block *sb,
                     ext4_group_t ngroup);
 extern const char *ext4_decode_error(struct super_block *sb, int errno,
                      char nbuf[16]);
 extern void ext4_mark_group_bitmap_corrupted(struct super_block *sb,
                          ext4_group_t block_group,
                          unsigned int flags);
 
 extern __printf(7, 8)
 void __ext4_error(struct super_block *, const char *, unsigned int, bool,
           int, __u64, const char *, ...);
 extern __printf(6, 7)
 void __ext4_error_inode(struct inode *, const char *, unsigned int,
             ext4_fsblk_t, int, const char *, ...);
 extern __printf(5, 6)
 void __ext4_error_file(struct file *, const char *, unsigned int, ext4_fsblk_t,
              const char *, ...);
 extern void __ext4_std_error(struct super_block *, const char *,
                  unsigned int, int);
 extern __printf(4, 5)
 void __ext4_warning(struct super_block *, const char *, unsigned int,
             const char *, ...);
 extern __printf(4, 5)
 void __ext4_warning_inode(const struct inode *inode, const char *function,
               unsigned int line, const char *fmt, ...);
 extern __printf(3, 4)
 void __ext4_msg(struct super_block *, const char *, const char *, ...);
 extern void __dump_mmp_msg(struct super_block *, struct mmp_struct *mmp,
                const char *, unsigned int, const char *);
 extern __printf(7, 8)
 void __ext4_grp_locked_error(const char *, unsigned int,
                  struct super_block *, ext4_group_t,
                  unsigned long, ext4_fsblk_t,
                  const char *, ...);
 
 #define EXT4_ERROR_INODE(inode, fmt, a...) \
     ext4_error_inode((inode), __func__, __LINE__, 0, (fmt), ## a)
 
 #define EXT4_ERROR_INODE_ERR(inode, err, fmt, a...)         \
     __ext4_error_inode((inode), __func__, __LINE__, 0, (err), (fmt), ## a)
 
 #define ext4_error_inode_block(inode, block, err, fmt, a...)        \
     __ext4_error_inode((inode), __func__, __LINE__, (block), (err), \
                (fmt), ## a)
 
 #define EXT4_ERROR_FILE(file, block, fmt, a...)             \
     ext4_error_file((file), __func__, __LINE__, (block), (fmt), ## a)
 
 #define ext4_abort(sb, err, fmt, a...)                  \
     __ext4_error((sb), __func__, __LINE__, true, (err), 0, (fmt), ## a)
 
 #ifdef CONFIG_PRINTK
 
 #define ext4_error_inode(inode, func, line, block, fmt, ...)        \
     __ext4_error_inode(inode, func, line, block, 0, fmt, ##__VA_ARGS__)
 #define ext4_error_inode_err(inode, func, line, block, err, fmt, ...)   \
     __ext4_error_inode((inode), (func), (line), (block),        \
                (err), (fmt), ##__VA_ARGS__)
 #define ext4_error_file(file, func, line, block, fmt, ...)      \
     __ext4_error_file(file, func, line, block, fmt, ##__VA_ARGS__)
 #define ext4_error(sb, fmt, ...)                    \
     __ext4_error((sb), __func__, __LINE__, false, 0, 0, (fmt),  \
         ##__VA_ARGS__)
 #define ext4_error_err(sb, err, fmt, ...)               \
     __ext4_error((sb), __func__, __LINE__, false, (err), 0, (fmt),  \
         ##__VA_ARGS__)
 #define ext4_warning(sb, fmt, ...)                  \
     __ext4_warning(sb, __func__, __LINE__, fmt, ##__VA_ARGS__)
 #define ext4_warning_inode(inode, fmt, ...)             \
     __ext4_warning_inode(inode, __func__, __LINE__, fmt, ##__VA_ARGS__)
 #define ext4_msg(sb, level, fmt, ...)               \
     __ext4_msg(sb, level, fmt, ##__VA_ARGS__)
 #define dump_mmp_msg(sb, mmp, msg)                  \
     __dump_mmp_msg(sb, mmp, __func__, __LINE__, msg)
 #define ext4_grp_locked_error(sb, grp, ino, block, fmt, ...)        \
     __ext4_grp_locked_error(__func__, __LINE__, sb, grp, ino, block, \
                 fmt, ##__VA_ARGS__)
 
 #else
 
 #define ext4_error_inode(inode, func, line, block, fmt, ...)        \
 do {                                    \
     no_printk(fmt, ##__VA_ARGS__);                  \
     __ext4_error_inode(inode, "", 0, block, 0, " ");        \
 } while (0)
 #define ext4_error_inode_err(inode, func, line, block, err, fmt, ...)   \
 do {                                    \
     no_printk(fmt, ##__VA_ARGS__);                  \
     __ext4_error_inode(inode, "", 0, block, err, " ");      \
 } while (0)
 #define ext4_error_file(file, func, line, block, fmt, ...)      \
 do {                                    \
     no_printk(fmt, ##__VA_ARGS__);                  \
     __ext4_error_file(file, "", 0, block, " ");         \
 } while (0)
 #define ext4_error(sb, fmt, ...)                    \
 do {                                    \
     no_printk(fmt, ##__VA_ARGS__);                  \
     __ext4_error(sb, "", 0, false, 0, 0, " ");          \
 } while (0)
 #define ext4_error_err(sb, err, fmt, ...)               \
 do {                                    \
     no_printk(fmt, ##__VA_ARGS__);                  \
     __ext4_error(sb, "", 0, false, err, 0, " ");            \
 } while (0)
 #define ext4_warning(sb, fmt, ...)                  \
 do {                                    \
     no_printk(fmt, ##__VA_ARGS__);                  \
     __ext4_warning(sb, "", 0, " ");                 \
 } while (0)
 #define ext4_warning_inode(inode, fmt, ...)             \
 do {                                    \
     no_printk(fmt, ##__VA_ARGS__);                  \
     __ext4_warning_inode(inode, "", 0, " ");            \
 } while (0)
 #define ext4_msg(sb, level, fmt, ...)                   \
 do {                                    \
     no_printk(fmt, ##__VA_ARGS__);                  \
     __ext4_msg(sb, "", " ");                    \
 } while (0)
 #define dump_mmp_msg(sb, mmp, msg)                  \
     __dump_mmp_msg(sb, mmp, "", 0, "")
 #define ext4_grp_locked_error(sb, grp, ino, block, fmt, ...)        \
 do {                                    \
     no_printk(fmt, ##__VA_ARGS__);              \
     __ext4_grp_locked_error("", 0, sb, grp, ino, block, " ");   \
 } while (0)
 
 #endif
 
 extern ext4_fsblk_t ext4_block_bitmap(struct super_block *sb,
                       struct ext4_group_desc *bg);
 extern ext4_fsblk_t ext4_inode_bitmap(struct super_block *sb,
                       struct ext4_group_desc *bg);
 extern ext4_fsblk_t ext4_inode_table(struct super_block *sb,
                      struct ext4_group_desc *bg);
 extern __u32 ext4_free_group_clusters(struct super_block *sb,
                       struct ext4_group_desc *bg);
 extern __u32 ext4_free_inodes_count(struct super_block *sb,
                  struct ext4_group_desc *bg);
 extern __u32 ext4_used_dirs_count(struct super_block *sb,
                 struct ext4_group_desc *bg);
 extern __u32 ext4_itable_unused_count(struct super_block *sb,
                    struct ext4_group_desc *bg);
 extern void ext4_block_bitmap_set(struct super_block *sb,
                   struct ext4_group_desc *bg, ext4_fsblk_t blk);
 extern void ext4_inode_bitmap_set(struct super_block *sb,
                   struct ext4_group_desc *bg, ext4_fsblk_t blk);
 extern void ext4_inode_table_set(struct super_block *sb,
                  struct ext4_group_desc *bg, ext4_fsblk_t blk);
 extern void ext4_free_group_clusters_set(struct super_block *sb,
                      struct ext4_group_desc *bg,
                      __u32 count);
 extern void ext4_free_inodes_set(struct super_block *sb,
                 struct ext4_group_desc *bg, __u32 count);
 extern void ext4_used_dirs_set(struct super_block *sb,
                 struct ext4_group_desc *bg, __u32 count);
 extern void ext4_itable_unused_set(struct super_block *sb,
                    struct ext4_group_desc *bg, __u32 count);
 extern int ext4_group_desc_csum_verify(struct super_block *sb, __u32 group,
                        struct ext4_group_desc *gdp);
 extern void ext4_group_desc_csum_set(struct super_block *sb, __u32 group,
                      struct ext4_group_desc *gdp);
 extern int ext4_register_li_request(struct super_block *sb,
                     ext4_group_t first_not_zeroed);
 
 static inline int ext4_has_metadata_csum(struct super_block *sb)
 {
     WARN_ON_ONCE(ext4_has_feature_metadata_csum(sb) &&
              !EXT4_SB(sb)->s_chksum_driver);
 
     return ext4_has_feature_metadata_csum(sb) &&
            (EXT4_SB(sb)->s_chksum_driver != NULL);
 }
 
 static inline int ext4_has_group_desc_csum(struct super_block *sb)
 {
     return ext4_has_feature_gdt_csum(sb) || ext4_has_metadata_csum(sb);
 }
 
 #define ext4_read_incompat_64bit_val(es, name) \
     (((es)->s_feature_incompat & cpu_to_le32(EXT4_FEATURE_INCOMPAT_64BIT) \
         ? (ext4_fsblk_t)le32_to_cpu(es->name##_hi) << 32 : 0) | \
         le32_to_cpu(es->name##_lo))
 
 static inline ext4_fsblk_t ext4_blocks_count(struct ext4_super_block *es)
 {
     return ext4_read_incompat_64bit_val(es, s_blocks_count);
 }
 
 static inline ext4_fsblk_t ext4_r_blocks_count(struct ext4_super_block *es)
 {
     return ext4_read_incompat_64bit_val(es, s_r_blocks_count);
 }
 
 static inline ext4_fsblk_t ext4_free_blocks_count(struct ext4_super_block *es)
 {
     return ext4_read_incompat_64bit_val(es, s_free_blocks_count);
 }
 
 static inline void ext4_blocks_count_set(struct ext4_super_block *es,
                      ext4_fsblk_t blk)
 {
     es->s_blocks_count_lo = cpu_to_le32((u32)blk);
     es->s_blocks_count_hi = cpu_to_le32(blk >> 32);
 }
 
 static inline void ext4_free_blocks_count_set(struct ext4_super_block *es,
                           ext4_fsblk_t blk)
 {
     es->s_free_blocks_count_lo = cpu_to_le32((u32)blk);
     es->s_free_blocks_count_hi = cpu_to_le32(blk >> 32);
 }
 
 static inline void ext4_r_blocks_count_set(struct ext4_super_block *es,
                        ext4_fsblk_t blk)
 {
     es->s_r_blocks_count_lo = cpu_to_le32((u32)blk);
     es->s_r_blocks_count_hi = cpu_to_le32(blk >> 32);
 }
 
 static inline loff_t ext4_isize(struct super_block *sb,
                 struct ext4_inode *raw_inode)
 {
     if (ext4_has_feature_largedir(sb) ||
         S_ISREG(le16_to_cpu(raw_inode->i_mode)))
         return ((loff_t)le32_to_cpu(raw_inode->i_size_high) << 32) |
             le32_to_cpu(raw_inode->i_size_lo);
 
     return (loff_t) le32_to_cpu(raw_inode->i_size_lo);
 }
 
 static inline void ext4_isize_set(struct ext4_inode *raw_inode, loff_t i_size)
 {
     raw_inode->i_size_lo = cpu_to_le32(i_size);
     raw_inode->i_size_high = cpu_to_le32(i_size >> 32);
 }
 
 static inline
 struct ext4_group_info *ext4_get_group_info(struct super_block *sb,
                         ext4_group_t group)
 {
      struct ext4_group_info **grp_info;
      long indexv, indexh;
      BUG_ON(group >= EXT4_SB(sb)->s_groups_count);
      indexv = group >> (EXT4_DESC_PER_BLOCK_BITS(sb));
      indexh = group & ((EXT4_DESC_PER_BLOCK(sb)) - 1);
      grp_info = sbi_array_rcu_deref(EXT4_SB(sb), s_group_info, indexv);
      return grp_info[indexh];
 }
 
 /*
  * Reading s_groups_count requires using smp_rmb() afterwards.  See
  * the locking protocol documented in the comments of ext4_group_add()
  * in resize.c
  */
 static inline ext4_group_t ext4_get_groups_count(struct super_block *sb)
 {
     ext4_group_t    ngroups = EXT4_SB(sb)->s_groups_count;
 
     smp_rmb();
     return ngroups;
 }
 
 static inline ext4_group_t ext4_flex_group(struct ext4_sb_info *sbi,
                          ext4_group_t block_group)
 {
     return block_group >> sbi->s_log_groups_per_flex;
 }
 
 static inline unsigned int ext4_flex_bg_size(struct ext4_sb_info *sbi)
 {
     return 1 << sbi->s_log_groups_per_flex;
 }
 
 #define ext4_std_error(sb, errno)               \
 do {                                \
     if ((errno))                        \
         __ext4_std_error((sb), __func__, __LINE__, (errno));    \
 } while (0)
 
 #ifdef CONFIG_SMP
 /* Each CPU can accumulate percpu_counter_batch clusters in their local
  * counters. So we need to make sure we have free clusters more
  * than percpu_counter_batch  * nr_cpu_ids. Also add a window of 4 times.
  */
 #define EXT4_FREECLUSTERS_WATERMARK (4 * (percpu_counter_batch * nr_cpu_ids))
 #else
 #define EXT4_FREECLUSTERS_WATERMARK 0
 #endif
 
 /* Update i_disksize. Requires i_rwsem to avoid races with truncate */
 static inline void ext4_update_i_disksize(struct inode *inode, loff_t newsize)
 {
     WARN_ON_ONCE(S_ISREG(inode->i_mode) &&
              !inode_is_locked(inode));
     down_write(&EXT4_I(inode)->i_data_sem);
     if (newsize > EXT4_I(inode)->i_disksize)
         WRITE_ONCE(EXT4_I(inode)->i_disksize, newsize);
     up_write(&EXT4_I(inode)->i_data_sem);
 }
 
 /* Update i_size, i_disksize. Requires i_rwsem to avoid races with truncate */
 static inline int ext4_update_inode_size(struct inode *inode, loff_t newsize)
 {
     int changed = 0;
 
     if (newsize > inode->i_size) {
         i_size_write(inode, newsize);
         changed = 1;
     }
     if (newsize > EXT4_I(inode)->i_disksize) {
         ext4_update_i_disksize(inode, newsize);
         changed |= 2;
     }
     return changed;
 }
 
 int ext4_update_disksize_before_punch(struct inode *inode, loff_t offset,
                       loff_t len);
 
 struct ext4_group_info {
     unsigned long   bb_state;
 #ifdef AGGRESSIVE_CHECK
     unsigned long   bb_check_counter;
 #endif
     struct rb_root  bb_free_root;
     ext4_grpblk_t   bb_first_free;  /* first free block */
     ext4_grpblk_t   bb_free;    /* total free blocks */
     ext4_grpblk_t   bb_fragments;   /* nr of freespace fragments */
     int     bb_avg_fragment_size_order; /* order of average
                                fragment in BG */
     ext4_grpblk_t   bb_largest_free_order;/* order of largest frag in BG */
     ext4_group_t    bb_group;   /* Group number */
     struct          list_head bb_prealloc_list;
 #ifdef DOUBLE_CHECK
     void            *bb_bitmap;
 #endif
     struct rw_semaphore alloc_sem;
     struct list_head bb_avg_fragment_size_node;
     struct list_head bb_largest_free_order_node;
     ext4_grpblk_t   bb_counters[];  /* Nr of free power-of-two-block
                      * regions, index is order.
                      * bb_counters[3] = 5 means
                      * 5 free 8-block regions. */
 };
 
 #define EXT4_GROUP_INFO_NEED_INIT_BIT       0
 #define EXT4_GROUP_INFO_WAS_TRIMMED_BIT     1
 #define EXT4_GROUP_INFO_BBITMAP_CORRUPT_BIT 2
 #define EXT4_GROUP_INFO_IBITMAP_CORRUPT_BIT 3
 #define EXT4_GROUP_INFO_BBITMAP_CORRUPT     \
     (1 << EXT4_GROUP_INFO_BBITMAP_CORRUPT_BIT)
 #define EXT4_GROUP_INFO_IBITMAP_CORRUPT     \
     (1 << EXT4_GROUP_INFO_IBITMAP_CORRUPT_BIT)
 #define EXT4_GROUP_INFO_BBITMAP_READ_BIT    4
 
 #define EXT4_MB_GRP_NEED_INIT(grp)  \
     (test_bit(EXT4_GROUP_INFO_NEED_INIT_BIT, &((grp)->bb_state)))
 #define EXT4_MB_GRP_BBITMAP_CORRUPT(grp)    \
     (test_bit(EXT4_GROUP_INFO_BBITMAP_CORRUPT_BIT, &((grp)->bb_state)))
 #define EXT4_MB_GRP_IBITMAP_CORRUPT(grp)    \
     (test_bit(EXT4_GROUP_INFO_IBITMAP_CORRUPT_BIT, &((grp)->bb_state)))
 
 #define EXT4_MB_GRP_WAS_TRIMMED(grp)    \
     (test_bit(EXT4_GROUP_INFO_WAS_TRIMMED_BIT, &((grp)->bb_state)))
 #define EXT4_MB_GRP_SET_TRIMMED(grp)    \
     (set_bit(EXT4_GROUP_INFO_WAS_TRIMMED_BIT, &((grp)->bb_state)))
 #define EXT4_MB_GRP_CLEAR_TRIMMED(grp)  \
     (clear_bit(EXT4_GROUP_INFO_WAS_TRIMMED_BIT, &((grp)->bb_state)))
 #define EXT4_MB_GRP_TEST_AND_SET_READ(grp)  \
     (test_and_set_bit(EXT4_GROUP_INFO_BBITMAP_READ_BIT, &((grp)->bb_state)))
 
 #define EXT4_MAX_CONTENTION     8
 #define EXT4_CONTENTION_THRESHOLD   2
 
 static inline spinlock_t *ext4_group_lock_ptr(struct super_block *sb,
                           ext4_group_t group)
 {
     return bgl_lock_ptr(EXT4_SB(sb)->s_blockgroup_lock, group);
 }
 
 /*
  * Returns true if the filesystem is busy enough that attempts to
  * access the block group locks has run into contention.
  */
 static inline int ext4_fs_is_busy(struct ext4_sb_info *sbi)
 {
     return (atomic_read(&sbi->s_lock_busy) > EXT4_CONTENTION_THRESHOLD);
 }
 
 static inline void ext4_lock_group(struct super_block *sb, ext4_group_t group)
 {
     spinlock_t *lock = ext4_group_lock_ptr(sb, group);
     if (spin_trylock(lock))
         /*
          * We're able to grab the lock right away, so drop the
          * lock contention counter.
          */
         atomic_add_unless(&EXT4_SB(sb)->s_lock_busy, -1, 0);
     else {
         /*
          * The lock is busy, so bump the contention counter,
          * and then wait on the spin lock.
          */
         atomic_add_unless(&EXT4_SB(sb)->s_lock_busy, 1,
                   EXT4_MAX_CONTENTION);
         spin_lock(lock);
     }
 }
 
 static inline void ext4_unlock_group(struct super_block *sb,
                     ext4_group_t group)
 {
     spin_unlock(ext4_group_lock_ptr(sb, group));
 }
 
 #ifdef CONFIG_QUOTA
 static inline bool ext4_quota_capable(struct super_block *sb)
 {
     return (test_opt(sb, QUOTA) || ext4_has_feature_quota(sb));
 }
 
 static inline bool ext4_is_quota_journalled(struct super_block *sb)
 {
     struct ext4_sb_info *sbi = EXT4_SB(sb);
 
     return (ext4_has_feature_quota(sb) ||
         sbi->s_qf_names[USRQUOTA] || sbi->s_qf_names[GRPQUOTA]);
 }
 int ext4_enable_quotas(struct super_block *sb);
 #endif
 
 /*
  * Block validity checking
  */
 #define ext4_check_indirect_blockref(inode, bh)             \
     ext4_check_blockref(__func__, __LINE__, inode,          \
                 (__le32 *)(bh)->b_data,         \
                 EXT4_ADDR_PER_BLOCK((inode)->i_sb))
 
 #define ext4_ind_check_inode(inode)                 \
     ext4_check_blockref(__func__, __LINE__, inode,          \
                 EXT4_I(inode)->i_data,          \
                 EXT4_NDIR_BLOCKS)
 
 /*
  * Inodes and files operations
  */
 
 /* dir.c */
 extern const struct file_operations ext4_dir_operations;
 
 /* file.c */
 extern const struct inode_operations ext4_file_inode_operations;
 extern const struct file_operations ext4_file_operations;
 extern loff_t ext4_llseek(struct file *file, loff_t offset, int origin);
 
 /* inline.c */
 extern int ext4_get_max_inline_size(struct inode *inode);
 extern int ext4_find_inline_data_nolock(struct inode *inode);
 extern int ext4_init_inline_data(handle_t *handle, struct inode *inode,
                  unsigned int len);
 extern int ext4_destroy_inline_data(handle_t *handle, struct inode *inode);
 
 extern int ext4_readpage_inline(struct inode *inode, struct page *page);
 extern int ext4_try_to_write_inline_data(struct address_space *mapping,
                      struct inode *inode,
                      loff_t pos, unsigned len,
                      struct page **pagep);
 extern int ext4_write_inline_data_end(struct inode *inode,
                       loff_t pos, unsigned len,
                       unsigned copied,
                       struct page *page);
 extern struct buffer_head *
 ext4_journalled_write_inline_data(struct inode *inode,
                   unsigned len,
                   struct page *page);
 extern int ext4_da_write_inline_data_begin(struct address_space *mapping,
                        struct inode *inode,
                        loff_t pos, unsigned len,
                        struct page **pagep,
                        void **fsdata);
 extern int ext4_try_add_inline_entry(handle_t *handle,
                      struct ext4_filename *fname,
                      struct inode *dir, struct inode *inode);
 extern int ext4_try_create_inline_dir(handle_t *handle,
                       struct inode *parent,
                       struct inode *inode);
 extern int ext4_read_inline_dir(struct file *filp,
                 struct dir_context *ctx,
                 int *has_inline_data);
 extern int ext4_inlinedir_to_tree(struct file *dir_file,
                   struct inode *dir, ext4_lblk_t block,
                   struct dx_hash_info *hinfo,
                   __u32 start_hash, __u32 start_minor_hash,
                   int *has_inline_data);
 extern struct buffer_head *ext4_find_inline_entry(struct inode *dir,
                     struct ext4_filename *fname,
                     struct ext4_dir_entry_2 **res_dir,
                     int *has_inline_data);
 extern int ext4_delete_inline_entry(handle_t *handle,
                     struct inode *dir,
                     struct ext4_dir_entry_2 *de_del,
                     struct buffer_head *bh,
                     int *has_inline_data);
 extern bool empty_inline_dir(struct inode *dir, int *has_inline_data);
 extern struct buffer_head *ext4_get_first_inline_block(struct inode *inode,
                     struct ext4_dir_entry_2 **parent_de,
                     int *retval);
 extern int ext4_inline_data_fiemap(struct inode *inode,
                    struct fiemap_extent_info *fieinfo,
                    int *has_inline, __u64 start, __u64 len);
 extern void *ext4_read_inline_link(struct inode *inode);
 
 struct iomap;
 extern int ext4_inline_data_iomap(struct inode *inode, struct iomap *iomap);
 
 extern int ext4_inline_data_truncate(struct inode *inode, int *has_inline);
 
 extern int ext4_convert_inline_data(struct inode *inode);
 
 static inline int ext4_has_inline_data(struct inode *inode)
 {
     return ext4_test_inode_flag(inode, EXT4_INODE_INLINE_DATA) &&
            EXT4_I(inode)->i_inline_off;
 }
 
 /* namei.c */
 extern const struct inode_operations ext4_dir_inode_operations;
 extern const struct inode_operations ext4_special_inode_operations;
 extern struct dentry *ext4_get_parent(struct dentry *child);
 extern struct ext4_dir_entry_2 *ext4_init_dot_dotdot(struct inode *inode,
                  struct ext4_dir_entry_2 *de,
                  int blocksize, int csum_size,
                  unsigned int parent_ino, int dotdot_real_len);
 extern void ext4_initialize_dirent_tail(struct buffer_head *bh,
                     unsigned int blocksize);
 extern int ext4_handle_dirty_dirblock(handle_t *handle, struct inode *inode,
                       struct buffer_head *bh);
 extern int __ext4_unlink(handle_t *handle, struct inode *dir, const struct qstr *d_name,
              struct inode *inode);
 extern int __ext4_link(struct inode *dir, struct inode *inode,
                struct dentry *dentry);
 
 #define S_SHIFT 12
 static const unsigned char ext4_type_by_mode[(S_IFMT >> S_SHIFT) + 1] = {
     [S_IFREG >> S_SHIFT]    = EXT4_FT_REG_FILE,
     [S_IFDIR >> S_SHIFT]    = EXT4_FT_DIR,
     [S_IFCHR >> S_SHIFT]    = EXT4_FT_CHRDEV,
     [S_IFBLK >> S_SHIFT]    = EXT4_FT_BLKDEV,
     [S_IFIFO >> S_SHIFT]    = EXT4_FT_FIFO,
     [S_IFSOCK >> S_SHIFT]   = EXT4_FT_SOCK,
     [S_IFLNK >> S_SHIFT]    = EXT4_FT_SYMLINK,
 };
 
 static inline void ext4_set_de_type(struct super_block *sb,
                 struct ext4_dir_entry_2 *de,
                 umode_t mode) {
     if (ext4_has_feature_filetype(sb))
         de->file_type = ext4_type_by_mode[(mode & S_IFMT)>>S_SHIFT];
 }
 
 /* readpages.c */
 extern int ext4_mpage_readpages(struct inode *inode,
         struct readahead_control *rac, struct page *page);
 extern int __init ext4_init_post_read_processing(void);
 extern void ext4_exit_post_read_processing(void);
 
 /* symlink.c */
 extern const struct inode_operations ext4_encrypted_symlink_inode_operations;
 extern const struct inode_operations ext4_symlink_inode_operations;
 extern const struct inode_operations ext4_fast_symlink_inode_operations;
 
 /* sysfs.c */
 extern void ext4_notify_error_sysfs(struct ext4_sb_info *sbi);
 extern int ext4_register_sysfs(struct super_block *sb);
 extern void ext4_unregister_sysfs(struct super_block *sb);
 extern int __init ext4_init_sysfs(void);
 extern void ext4_exit_sysfs(void);
 
 /* block_validity */
 extern void ext4_release_system_zone(struct super_block *sb);
 extern int ext4_setup_system_zone(struct super_block *sb);
 extern int __init ext4_init_system_zone(void);
 extern void ext4_exit_system_zone(void);
 extern int ext4_inode_block_valid(struct inode *inode,
                   ext4_fsblk_t start_blk,
                   unsigned int count);
 extern int ext4_check_blockref(const char *, unsigned int,
                    struct inode *, __le32 *, unsigned int);
 extern int ext4_sb_block_valid(struct super_block *sb, struct inode *inode,
                 ext4_fsblk_t start_blk, unsigned int count);
 
 
 /* extents.c */
 struct ext4_ext_path;
 struct ext4_extent;
 
 /*
  * Maximum number of logical blocks in a file; ext4_extent's ee_block is
  * __le32.
  */
 #define EXT_MAX_BLOCKS  0xffffffff
 
 extern void ext4_ext_tree_init(handle_t *handle, struct inode *inode);
 extern int ext4_ext_index_trans_blocks(struct inode *inode, int extents);
 extern int ext4_ext_map_blocks(handle_t *handle, struct inode *inode,
                    struct ext4_map_blocks *map, int flags);
 extern int ext4_ext_truncate(handle_t *, struct inode *);
 extern int ext4_ext_remove_space(struct inode *inode, ext4_lblk_t start,
                  ext4_lblk_t end);
 extern void ext4_ext_init(struct super_block *);
 extern void ext4_ext_release(struct super_block *);
 extern long ext4_fallocate(struct file *file, int mode, loff_t offset,
               loff_t len);
 extern int ext4_convert_unwritten_extents(handle_t *handle, struct inode *inode,
                       loff_t offset, ssize_t len);
 extern int ext4_convert_unwritten_io_end_vec(handle_t *handle,
                          ext4_io_end_t *io_end);
 extern int ext4_map_blocks(handle_t *handle, struct inode *inode,
                struct ext4_map_blocks *map, int flags);
 extern int ext4_ext_calc_credits_for_single_extent(struct inode *inode,
                            int num,
                            struct ext4_ext_path *path);
 extern int ext4_ext_insert_extent(handle_t *, struct inode *,
                   struct ext4_ext_path **,
                   struct ext4_extent *, int);
 extern struct ext4_ext_path *ext4_find_extent(struct inode *, ext4_lblk_t,
                           struct ext4_ext_path **,
                           int flags);
 extern void ext4_ext_drop_refs(struct ext4_ext_path *);
 extern int ext4_ext_check_inode(struct inode *inode);
 extern ext4_lblk_t ext4_ext_next_allocated_block(struct ext4_ext_path *path);
 extern int ext4_fiemap(struct inode *inode, struct fiemap_extent_info *fieinfo,
             __u64 start, __u64 len);
 extern int ext4_get_es_cache(struct inode *inode,
                  struct fiemap_extent_info *fieinfo,
                  __u64 start, __u64 len);
 extern int ext4_ext_precache(struct inode *inode);
 extern int ext4_swap_extents(handle_t *handle, struct inode *inode1,
                 struct inode *inode2, ext4_lblk_t lblk1,
                  ext4_lblk_t lblk2,  ext4_lblk_t count,
                  int mark_unwritten,int *err);
 extern int ext4_clu_mapped(struct inode *inode, ext4_lblk_t lclu);
 extern int ext4_datasem_ensure_credits(handle_t *handle, struct inode *inode,
                        int check_cred, int restart_cred,
                        int revoke_cred);
 extern void ext4_ext_replay_shrink_inode(struct inode *inode, ext4_lblk_t end);
 extern int ext4_ext_replay_set_iblocks(struct inode *inode);
 extern int ext4_ext_replay_update_ex(struct inode *inode, ext4_lblk_t start,
         int len, int unwritten, ext4_fsblk_t pblk);
 extern int ext4_ext_clear_bb(struct inode *inode);
 
 
 /* move_extent.c */
 extern void ext4_double_down_write_data_sem(struct inode *first,
                         struct inode *second);
 extern void ext4_double_up_write_data_sem(struct inode *orig_inode,
                       struct inode *donor_inode);
 extern int ext4_move_extents(struct file *o_filp, struct file *d_filp,
                  __u64 start_orig, __u64 start_donor,
                  __u64 len, __u64 *moved_len);
 
 /* page-io.c */
 extern int __init ext4_init_pageio(void);
 extern void ext4_exit_pageio(void);
 extern ext4_io_end_t *ext4_init_io_end(struct inode *inode, gfp_t flags);
 extern ext4_io_end_t *ext4_get_io_end(ext4_io_end_t *io_end);
 extern int ext4_put_io_end(ext4_io_end_t *io_end);
 extern void ext4_put_io_end_defer(ext4_io_end_t *io_end);
 extern void ext4_io_submit_init(struct ext4_io_submit *io,
                 struct writeback_control *wbc);
 extern void ext4_end_io_rsv_work(struct work_struct *work);
 extern void ext4_io_submit(struct ext4_io_submit *io);
 extern int ext4_bio_write_page(struct ext4_io_submit *io,
                    struct page *page,
                    int len,
                    bool keep_towrite);
 extern struct ext4_io_end_vec *ext4_alloc_io_end_vec(ext4_io_end_t *io_end);
 extern struct ext4_io_end_vec *ext4_last_io_end_vec(ext4_io_end_t *io_end);
 
 /* mmp.c */
 extern int ext4_multi_mount_protect(struct super_block *, ext4_fsblk_t);
 
 /* mmp.c */
 extern void ext4_stop_mmpd(struct ext4_sb_info *sbi);
 
 /* verity.c */
 extern const struct fsverity_operations ext4_verityops;
 
 /* orphan.c */
 extern int ext4_orphan_add(handle_t *, struct inode *);
 extern int ext4_orphan_del(handle_t *, struct inode *);
 extern void ext4_orphan_cleanup(struct super_block *sb,
                 struct ext4_super_block *es);
 extern void ext4_release_orphan_info(struct super_block *sb);
 extern int ext4_init_orphan_info(struct super_block *sb);
 extern int ext4_orphan_file_empty(struct super_block *sb);
 extern void ext4_orphan_file_block_trigger(
                 struct jbd2_buffer_trigger_type *triggers,
                 struct buffer_head *bh,
                 void *data, size_t size);
 
 /*
  * Add new method to test whether block and inode bitmaps are properly
  * initialized. With uninit_bg reading the block from disk is not enough
  * to mark the bitmap uptodate. We need to also zero-out the bitmap
  */
 #define BH_BITMAP_UPTODATE BH_JBDPrivateStart
 
 static inline int bitmap_uptodate(struct buffer_head *bh)
 {
     return (buffer_uptodate(bh) &&
             test_bit(BH_BITMAP_UPTODATE, &(bh)->b_state));
 }
 static inline void set_bitmap_uptodate(struct buffer_head *bh)
 {
     set_bit(BH_BITMAP_UPTODATE, &(bh)->b_state);
 }
 
 #define in_range(b, first, len) ((b) >= (first) && (b) <= (first) + (len) - 1)
 
 /* For ioend & aio unwritten conversion wait queues */
 #define EXT4_WQ_HASH_SZ     37
 #define ext4_ioend_wq(v)   (&ext4__ioend_wq[((unsigned long)(v)) %\
                         EXT4_WQ_HASH_SZ])
 extern wait_queue_head_t ext4__ioend_wq[EXT4_WQ_HASH_SZ];
 
 extern int ext4_resize_begin(struct super_block *sb);
 extern int ext4_resize_end(struct super_block *sb, bool update_backups);
 
 static inline void ext4_set_io_unwritten_flag(struct inode *inode,
                           struct ext4_io_end *io_end)
 {
     if (!(io_end->flag & EXT4_IO_END_UNWRITTEN)) {
         io_end->flag |= EXT4_IO_END_UNWRITTEN;
         atomic_inc(&EXT4_I(inode)->i_unwritten);
     }
 }
 
 static inline void ext4_clear_io_unwritten_flag(ext4_io_end_t *io_end)
 {
     struct inode *inode = io_end->inode;
 
     if (io_end->flag & EXT4_IO_END_UNWRITTEN) {
         io_end->flag &= ~EXT4_IO_END_UNWRITTEN;
         /* Wake up anyone waiting on unwritten extent conversion */
         if (atomic_dec_and_test(&EXT4_I(inode)->i_unwritten))
             wake_up_all(ext4_ioend_wq(inode));
     }
 }
 
 extern const struct iomap_ops ext4_iomap_ops;
 extern const struct iomap_ops ext4_iomap_overwrite_ops;
 extern const struct iomap_ops ext4_iomap_report_ops;
 
 static inline int ext4_buffer_uptodate(struct buffer_head *bh)
 {
     /*
      * If the buffer has the write error flag, we have failed
      * to write out data in the block.  In this  case, we don't
      * have to read the block because we may read the old data
      * successfully.
      */
     if (buffer_write_io_error(bh))
         set_buffer_uptodate(bh);
     return buffer_uptodate(bh);
 }
 
 #endif  /* __KERNEL__ */
 
 #define EFSBADCRC   EBADMSG     /* Bad CRC detected */
 #define EFSCORRUPTED    EUCLEAN     /* Filesystem is corrupted */
 
 #endif  /* _EXT4_H */