Add the rt linux 4.1.3-rt3 as base
[kvmfornfv.git] / kernel / fs / ext4 / ext4.h
diff --git a/kernel/fs/ext4/ext4.h b/kernel/fs/ext4/ext4.h
new file mode 100644 (file)
index 0000000..9a83f14
--- /dev/null
@@ -0,0 +1,2998 @@
+/*
+ *  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/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/blockgroup_lock.h>
+#include <linux/percpu_counter.h>
+#include <linux/ratelimit.h>
+#include <crypto/hash.h>
+#include <linux/falloc.h>
+#ifdef __KERNEL__
+#include <linux/compat.h>
+#endif
+
+/*
+ * The fourth extended filesystem constants/structures
+ */
+
+/*
+ * Define EXT4FS_DEBUG to produce debug messages
+ */
+#undef EXT4FS_DEBUG
+
+/*
+ * Debug code
+ */
+#ifdef EXT4FS_DEBUG
+#define ext4_debug(f, a...)                                            \
+       do {                                                            \
+               printk(KERN_DEBUG "EXT4-fs DEBUG (%s, %d): %s:",        \
+                       __FILE__, __LINE__, __func__);                  \
+               printk(KERN_DEBUG f, ## a);                             \
+       } while (0)
+#else
+#define ext4_debug(fmt, ...)   no_printk(fmt, ##__VA_ARGS__)
+#endif
+
+/*
+ * Turn on EXT_DEBUG to get lots of info about extents operations.
+ */
+#define EXT_DEBUG__
+#ifdef EXT_DEBUG
+#define ext_debug(fmt, ...)    printk(fmt, ##__VA_ARGS__)
+#else
+#define ext_debug(fmt, ...)    no_printk(fmt, ##__VA_ARGS__)
+#endif
+
+#define EXT4_ERROR_INODE(inode, fmt, a...) \
+       ext4_error_inode((inode), __func__, __LINE__, 0, (fmt), ## a)
+
+#define EXT4_ERROR_INODE_BLOCK(inode, block, fmt, a...)                        \
+       ext4_error_inode((inode), __func__, __LINE__, (block), (fmt), ## a)
+
+#define EXT4_ERROR_FILE(file, block, fmt, a...)                                \
+       ext4_error_file((file), __func__, __LINE__, (block), (fmt), ## a)
+
+/* 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;
+
+/*
+ * Flags used in mballoc's allocation_context flags field.
+ *
+ * Also used to show what's going on for debugging purposes when the
+ * flag field is exported via the traceport interface
+ */
+
+/* prefer goal again. length */
+#define EXT4_MB_HINT_MERGE             0x0001
+/* blocks already reserved */
+#define EXT4_MB_HINT_RESERVED          0x0002
+/* metadata is being allocated */
+#define EXT4_MB_HINT_METADATA          0x0004
+/* first blocks in the file */
+#define EXT4_MB_HINT_FIRST             0x0008
+/* search for the best chunk */
+#define EXT4_MB_HINT_BEST              0x0010
+/* data is being allocated */
+#define EXT4_MB_HINT_DATA              0x0020
+/* don't preallocate (for tails) */
+#define EXT4_MB_HINT_NOPREALLOC                0x0040
+/* allocate for locality group */
+#define EXT4_MB_HINT_GROUP_ALLOC       0x0080
+/* allocate goal blocks or none */
+#define EXT4_MB_HINT_GOAL_ONLY         0x0100
+/* goal is meaningful */
+#define EXT4_MB_HINT_TRY_GOAL          0x0200
+/* blocks already pre-reserved by delayed allocation */
+#define EXT4_MB_DELALLOC_RESERVED      0x0400
+/* We are doing stream allocation */
+#define EXT4_MB_STREAM_ALLOC           0x0800
+/* Use reserved root blocks if needed */
+#define EXT4_MB_USE_ROOT_BLOCKS                0x1000
+/* Use blocks from reserved pool */
+#define EXT4_MB_USE_RESERVED           0x2000
+
+struct ext4_allocation_request {
+       /* target inode for block we're allocating */
+       struct inode *inode;
+       /* how many blocks we want to allocate */
+       unsigned int len;
+       /* logical block in target inode */
+       ext4_lblk_t logical;
+       /* the closest logical allocated block to the left */
+       ext4_lblk_t lleft;
+       /* the closest logical allocated block to the right */
+       ext4_lblk_t lright;
+       /* phys. target (a hint) */
+       ext4_fsblk_t goal;
+       /* phys. block for the closest logical allocated block to the left */
+       ext4_fsblk_t pleft;
+       /* phys. block for the closest logical allocated block to the right */
+       ext4_fsblk_t pright;
+       /* flags. see above EXT4_MB_HINT_* */
+       unsigned int flags;
+};
+
+/*
+ * Logical to physical block mapping, used by ext4_map_blocks()
+ *
+ * This structure is used to pass requests into ext4_map_blocks() as
+ * well as to store the information returned by ext4_map_blocks().  It
+ * takes less room on the stack than a struct buffer_head.
+ */
+#define EXT4_MAP_NEW           (1 << BH_New)
+#define EXT4_MAP_MAPPED                (1 << BH_Mapped)
+#define EXT4_MAP_UNWRITTEN     (1 << BH_Unwritten)
+#define EXT4_MAP_BOUNDARY      (1 << BH_Boundary)
+#define EXT4_MAP_FLAGS         (EXT4_MAP_NEW | EXT4_MAP_MAPPED |\
+                                EXT4_MAP_UNWRITTEN | EXT4_MAP_BOUNDARY)
+
+struct ext4_map_blocks {
+       ext4_fsblk_t m_pblk;
+       ext4_lblk_t m_lblk;
+       unsigned int m_len;
+       unsigned int m_flags;
+};
+
+/*
+ * Flags for ext4_io_end->flags
+ */
+#define        EXT4_IO_END_UNWRITTEN   0x0001
+
+/*
+ * For converting unwritten extents on a work queue. 'handle' is used for
+ * buffered writeback.
+ */
+typedef struct ext4_io_end {
+       struct list_head        list;           /* per-file finished IO list */
+       handle_t                *handle;        /* handle reserved for extent
+                                                * conversion */
+       struct inode            *inode;         /* file being written to */
+       struct bio              *bio;           /* Linked list of completed
+                                                * bios covering the extent */
+       unsigned int            flag;           /* unwritten or not */
+       loff_t                  offset;         /* offset in the file */
+       ssize_t                 size;           /* size of the extent */
+       atomic_t                count;          /* reference counter */
+} ext4_io_end_t;
+
+struct ext4_io_submit {
+       int                     io_op;
+       struct bio              *io_bio;
+       ext4_io_end_t           *io_end;
+       sector_t                io_next_block;
+};
+
+/*
+ * Special inodes numbers
+ */
+#define        EXT4_BAD_INO             1      /* Bad blocks inode */
+#define EXT4_ROOT_INO           2      /* Root inode */
+#define EXT4_USR_QUOTA_INO      3      /* User quota inode */
+#define EXT4_GRP_QUOTA_INO      4      /* Group quota inode */
+#define EXT4_BOOT_LOADER_INO    5      /* Boot loader inode */
+#define EXT4_UNDEL_DIR_INO      6      /* Undelete directory inode */
+#define EXT4_RESIZE_INO                 7      /* Reserved group descriptors inode */
+#define EXT4_JOURNAL_INO        8      /* Journal inode */
+
+/* First non-reserved inode for old ext4 filesystems */
+#define EXT4_GOOD_OLD_FIRST_INO        11
+
+/*
+ * Maximal count of links to a file
+ */
+#define EXT4_LINK_MAX          65000
+
+/*
+ * Macro-instructions used to manage several block sizes
+ */
+#define EXT4_MIN_BLOCK_SIZE            1024
+#define        EXT4_MAX_BLOCK_SIZE             65536
+#define EXT4_MIN_BLOCK_LOG_SIZE                10
+#define EXT4_MAX_BLOCK_LOG_SIZE                16
+#ifdef __KERNEL__
+# define EXT4_BLOCK_SIZE(s)            ((s)->s_blocksize)
+#else
+# define EXT4_BLOCK_SIZE(s)            (EXT4_MIN_BLOCK_SIZE << (s)->s_log_block_size)
+#endif
+#define        EXT4_ADDR_PER_BLOCK(s)          (EXT4_BLOCK_SIZE(s) / sizeof(__u32))
+#define EXT4_CLUSTER_SIZE(s)           (EXT4_BLOCK_SIZE(s) << \
+                                        EXT4_SB(s)->s_cluster_bits)
+#ifdef __KERNEL__
+# define EXT4_BLOCK_SIZE_BITS(s)       ((s)->s_blocksize_bits)
+# define EXT4_CLUSTER_BITS(s)          (EXT4_SB(s)->s_cluster_bits)
+#else
+# define EXT4_BLOCK_SIZE_BITS(s)       ((s)->s_log_block_size + 10)
+#endif
+#ifdef __KERNEL__
+#define        EXT4_ADDR_PER_BLOCK_BITS(s)     (EXT4_SB(s)->s_addr_per_block_bits)
+#define EXT4_INODE_SIZE(s)             (EXT4_SB(s)->s_inode_size)
+#define EXT4_FIRST_INO(s)              (EXT4_SB(s)->s_first_ino)
+#else
+#define EXT4_INODE_SIZE(s)     (((s)->s_rev_level == EXT4_GOOD_OLD_REV) ? \
+                                EXT4_GOOD_OLD_INODE_SIZE : \
+                                (s)->s_inode_size)
+#define EXT4_FIRST_INO(s)      (((s)->s_rev_level == EXT4_GOOD_OLD_REV) ? \
+                                EXT4_GOOD_OLD_FIRST_INO : \
+                                (s)->s_first_ino)
+#endif
+#define EXT4_BLOCK_ALIGN(size, blkbits)                ALIGN((size), (1 << (blkbits)))
+
+/* Translate a block number to a cluster number */
+#define EXT4_B2C(sbi, blk)     ((blk) >> (sbi)->s_cluster_bits)
+/* Translate a cluster number to a block number */
+#define EXT4_C2B(sbi, cluster) ((cluster) << (sbi)->s_cluster_bits)
+/* Translate # of blks to # of clusters */
+#define EXT4_NUM_B2C(sbi, blks)        (((blks) + (sbi)->s_cluster_ratio - 1) >> \
+                                (sbi)->s_cluster_bits)
+/* Mask out the low bits to get the starting block of the cluster */
+#define EXT4_PBLK_CMASK(s, pblk) ((pblk) &                             \
+                                 ~((ext4_fsblk_t) (s)->s_cluster_ratio - 1))
+#define EXT4_LBLK_CMASK(s, lblk) ((lblk) &                             \
+                                 ~((ext4_lblk_t) (s)->s_cluster_ratio - 1))
+/* Get the cluster offset */
+#define EXT4_PBLK_COFF(s, pblk) ((pblk) &                              \
+                                ((ext4_fsblk_t) (s)->s_cluster_ratio - 1))
+#define EXT4_LBLK_COFF(s, lblk) ((lblk) &                              \
+                                ((ext4_lblk_t) (s)->s_cluster_ratio - 1))
+
+/*
+ * Structure of a blocks group descriptor
+ */
+struct ext4_group_desc
+{
+       __le32  bg_block_bitmap_lo;     /* Blocks bitmap block */
+       __le32  bg_inode_bitmap_lo;     /* Inodes bitmap block */
+       __le32  bg_inode_table_lo;      /* Inodes table block */
+       __le16  bg_free_blocks_count_lo;/* Free blocks count */
+       __le16  bg_free_inodes_count_lo;/* Free inodes count */
+       __le16  bg_used_dirs_count_lo;  /* Directories count */
+       __le16  bg_flags;               /* EXT4_BG_flags (INODE_UNINIT, etc) */
+       __le32  bg_exclude_bitmap_lo;   /* Exclude bitmap for snapshots */
+       __le16  bg_block_bitmap_csum_lo;/* crc32c(s_uuid+grp_num+bbitmap) LE */
+       __le16  bg_inode_bitmap_csum_lo;/* crc32c(s_uuid+grp_num+ibitmap) LE */
+       __le16  bg_itable_unused_lo;    /* Unused inodes count */
+       __le16  bg_checksum;            /* crc16(sb_uuid+group+desc) */
+       __le32  bg_block_bitmap_hi;     /* Blocks bitmap block MSB */
+       __le32  bg_inode_bitmap_hi;     /* Inodes bitmap block MSB */
+       __le32  bg_inode_table_hi;      /* Inodes table block MSB */
+       __le16  bg_free_blocks_count_hi;/* Free blocks count MSB */
+       __le16  bg_free_inodes_count_hi;/* Free inodes count MSB */
+       __le16  bg_used_dirs_count_hi;  /* Directories count MSB */
+       __le16  bg_itable_unused_hi;    /* Unused inodes count MSB */
+       __le32  bg_exclude_bitmap_hi;   /* Exclude bitmap block MSB */
+       __le16  bg_block_bitmap_csum_hi;/* crc32c(s_uuid+grp_num+bbitmap) BE */
+       __le16  bg_inode_bitmap_csum_hi;/* crc32c(s_uuid+grp_num+ibitmap) BE */
+       __u32   bg_reserved;
+};
+
+#define EXT4_BG_INODE_BITMAP_CSUM_HI_END       \
+       (offsetof(struct ext4_group_desc, bg_inode_bitmap_csum_hi) + \
+        sizeof(__le16))
+#define EXT4_BG_BLOCK_BITMAP_CSUM_HI_END       \
+       (offsetof(struct ext4_group_desc, bg_block_bitmap_csum_hi) + \
+        sizeof(__le16))
+
+/*
+ * Structure of a flex block group info
+ */
+
+struct flex_groups {
+       atomic64_t      free_clusters;
+       atomic_t        free_inodes;
+       atomic_t        used_dirs;
+};
+
+#define EXT4_BG_INODE_UNINIT   0x0001 /* Inode table/bitmap not in use */
+#define EXT4_BG_BLOCK_UNINIT   0x0002 /* Block bitmap not in use */
+#define EXT4_BG_INODE_ZEROED   0x0004 /* On-disk itable initialized to zero */
+
+/*
+ * Macro-instructions used to manage group descriptors
+ */
+#define EXT4_MIN_DESC_SIZE             32
+#define EXT4_MIN_DESC_SIZE_64BIT       64
+#define        EXT4_MAX_DESC_SIZE              EXT4_MIN_BLOCK_SIZE
+#define EXT4_DESC_SIZE(s)              (EXT4_SB(s)->s_desc_size)
+#ifdef __KERNEL__
+# define EXT4_BLOCKS_PER_GROUP(s)      (EXT4_SB(s)->s_blocks_per_group)
+# define EXT4_CLUSTERS_PER_GROUP(s)    (EXT4_SB(s)->s_clusters_per_group)
+# define EXT4_DESC_PER_BLOCK(s)                (EXT4_SB(s)->s_desc_per_block)
+# define EXT4_INODES_PER_GROUP(s)      (EXT4_SB(s)->s_inodes_per_group)
+# define EXT4_DESC_PER_BLOCK_BITS(s)   (EXT4_SB(s)->s_desc_per_block_bits)
+#else
+# define EXT4_BLOCKS_PER_GROUP(s)      ((s)->s_blocks_per_group)
+# define EXT4_DESC_PER_BLOCK(s)                (EXT4_BLOCK_SIZE(s) / EXT4_DESC_SIZE(s))
+# define EXT4_INODES_PER_GROUP(s)      ((s)->s_inodes_per_group)
+#endif
+
+/*
+ * Constants relative to the data blocks
+ */
+#define        EXT4_NDIR_BLOCKS                12
+#define        EXT4_IND_BLOCK                  EXT4_NDIR_BLOCKS
+#define        EXT4_DIND_BLOCK                 (EXT4_IND_BLOCK + 1)
+#define        EXT4_TIND_BLOCK                 (EXT4_DIND_BLOCK + 1)
+#define        EXT4_N_BLOCKS                   (EXT4_TIND_BLOCK + 1)
+
+/*
+ * Inode flags
+ */
+#define        EXT4_SECRM_FL                   0x00000001 /* Secure deletion */
+#define        EXT4_UNRM_FL                    0x00000002 /* Undelete */
+#define        EXT4_COMPR_FL                   0x00000004 /* Compress file */
+#define EXT4_SYNC_FL                   0x00000008 /* Synchronous updates */
+#define EXT4_IMMUTABLE_FL              0x00000010 /* Immutable file */
+#define EXT4_APPEND_FL                 0x00000020 /* writes to file may only append */
+#define EXT4_NODUMP_FL                 0x00000040 /* do not dump file */
+#define EXT4_NOATIME_FL                        0x00000080 /* do not update atime */
+/* Reserved for compression usage... */
+#define EXT4_DIRTY_FL                  0x00000100
+#define EXT4_COMPRBLK_FL               0x00000200 /* One or more compressed clusters */
+#define EXT4_NOCOMPR_FL                        0x00000400 /* Don't compress */
+       /* nb: was previously EXT2_ECOMPR_FL */
+#define EXT4_ENCRYPT_FL                        0x00000800 /* encrypted file */
+/* End compression flags --- maybe not all used */
+#define EXT4_INDEX_FL                  0x00001000 /* hash-indexed directory */
+#define EXT4_IMAGIC_FL                 0x00002000 /* AFS directory */
+#define EXT4_JOURNAL_DATA_FL           0x00004000 /* file data should be journaled */
+#define EXT4_NOTAIL_FL                 0x00008000 /* file tail should not be merged */
+#define EXT4_DIRSYNC_FL                        0x00010000 /* dirsync behaviour (directories only) */
+#define EXT4_TOPDIR_FL                 0x00020000 /* Top of directory hierarchies*/
+#define EXT4_HUGE_FILE_FL               0x00040000 /* Set to each huge file */
+#define EXT4_EXTENTS_FL                        0x00080000 /* Inode uses extents */
+#define EXT4_EA_INODE_FL               0x00200000 /* Inode used for large EA */
+#define EXT4_EOFBLOCKS_FL              0x00400000 /* Blocks allocated beyond EOF */
+#define EXT4_INLINE_DATA_FL            0x10000000 /* Inode has inline data. */
+#define EXT4_RESERVED_FL               0x80000000 /* reserved for ext4 lib */
+
+#define EXT4_FL_USER_VISIBLE           0x004BDFFF /* User visible flags */
+#define EXT4_FL_USER_MODIFIABLE                0x004380FF /* User modifiable flags */
+
+/* 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)
+
+/* Flags that are appropriate for regular files (all but dir-specific ones). */
+#define EXT4_REG_FLMASK (~(EXT4_DIRSYNC_FL | EXT4_TOPDIR_FL))
+
+/* Flags that are appropriate for non-directories/regular files. */
+#define EXT4_OTHER_FLMASK (EXT4_NODUMP_FL | EXT4_NOATIME_FL)
+
+/* Mask out flags that are inappropriate for the given type of inode. */
+static inline __u32 ext4_mask_flags(umode_t mode, __u32 flags)
+{
+       if (S_ISDIR(mode))
+               return flags;
+       else if (S_ISREG(mode))
+               return flags & EXT4_REG_FLMASK;
+       else
+               return flags & EXT4_OTHER_FLMASK;
+}
+
+/*
+ * Inode flags used for atomic set/get
+ */
+enum {
+       EXT4_INODE_SECRM        = 0,    /* Secure deletion */
+       EXT4_INODE_UNRM         = 1,    /* Undelete */
+       EXT4_INODE_COMPR        = 2,    /* Compress file */
+       EXT4_INODE_SYNC         = 3,    /* Synchronous updates */
+       EXT4_INODE_IMMUTABLE    = 4,    /* Immutable file */
+       EXT4_INODE_APPEND       = 5,    /* writes to file may only append */
+       EXT4_INODE_NODUMP       = 6,    /* do not dump file */
+       EXT4_INODE_NOATIME      = 7,    /* do not update atime */
+/* Reserved for compression usage... */
+       EXT4_INODE_DIRTY        = 8,
+       EXT4_INODE_COMPRBLK     = 9,    /* One or more compressed clusters */
+       EXT4_INODE_NOCOMPR      = 10,   /* Don't compress */
+       EXT4_INODE_ENCRYPT      = 11,   /* Encrypted file */
+/* End compression flags --- maybe not all used */
+       EXT4_INODE_INDEX        = 12,   /* hash-indexed directory */
+       EXT4_INODE_IMAGIC       = 13,   /* AFS directory */
+       EXT4_INODE_JOURNAL_DATA = 14,   /* file data should be journaled */
+       EXT4_INODE_NOTAIL       = 15,   /* file tail should not be merged */
+       EXT4_INODE_DIRSYNC      = 16,   /* dirsync behaviour (directories only) */
+       EXT4_INODE_TOPDIR       = 17,   /* Top of directory hierarchies*/
+       EXT4_INODE_HUGE_FILE    = 18,   /* Set to each huge file */
+       EXT4_INODE_EXTENTS      = 19,   /* Inode uses extents */
+       EXT4_INODE_EA_INODE     = 21,   /* Inode used for large EA */
+       EXT4_INODE_EOFBLOCKS    = 22,   /* Blocks allocated beyond EOF */
+       EXT4_INODE_INLINE_DATA  = 28,   /* Data in inode. */
+       EXT4_INODE_RESERVED     = 31,   /* reserved for ext4 lib */
+};
+
+/*
+ * Since it's pretty easy to mix up bit numbers and hex values, we use a
+ * build-time check to make sure that EXT4_XXX_FL is consistent with respect to
+ * EXT4_INODE_XXX. If all is well, the macros will be dropped, so, it won't cost
+ * any extra space in the compiled kernel image, otherwise, the build will fail.
+ * It's important that these values are the same, since we are using
+ * EXT4_INODE_XXX to test for flag values, but EXT4_XXX_FL must be consistent
+ * with the values of FS_XXX_FL defined in include/linux/fs.h and the on-disk
+ * values found in ext2, ext3 and ext4 filesystems, and of course the values
+ * defined in e2fsprogs.
+ *
+ * It's not paranoia if the Murphy's Law really *is* out to get you.  :-)
+ */
+#define TEST_FLAG_VALUE(FLAG) (EXT4_##FLAG##_FL == (1 << EXT4_INODE_##FLAG))
+#define CHECK_FLAG_VALUE(FLAG) BUILD_BUG_ON(!TEST_FLAG_VALUE(FLAG))
+
+static inline void ext4_check_flag_values(void)
+{
+       CHECK_FLAG_VALUE(SECRM);
+       CHECK_FLAG_VALUE(UNRM);
+       CHECK_FLAG_VALUE(COMPR);
+       CHECK_FLAG_VALUE(SYNC);
+       CHECK_FLAG_VALUE(IMMUTABLE);
+       CHECK_FLAG_VALUE(APPEND);
+       CHECK_FLAG_VALUE(NODUMP);
+       CHECK_FLAG_VALUE(NOATIME);
+       CHECK_FLAG_VALUE(DIRTY);
+       CHECK_FLAG_VALUE(COMPRBLK);
+       CHECK_FLAG_VALUE(NOCOMPR);
+       CHECK_FLAG_VALUE(ENCRYPT);
+       CHECK_FLAG_VALUE(INDEX);
+       CHECK_FLAG_VALUE(IMAGIC);
+       CHECK_FLAG_VALUE(JOURNAL_DATA);
+       CHECK_FLAG_VALUE(NOTAIL);
+       CHECK_FLAG_VALUE(DIRSYNC);
+       CHECK_FLAG_VALUE(TOPDIR);
+       CHECK_FLAG_VALUE(HUGE_FILE);
+       CHECK_FLAG_VALUE(EXTENTS);
+       CHECK_FLAG_VALUE(EA_INODE);
+       CHECK_FLAG_VALUE(EOFBLOCKS);
+       CHECK_FLAG_VALUE(INLINE_DATA);
+       CHECK_FLAG_VALUE(RESERVED);
+}
+
+/* Used to pass group descriptor data when online resize is done */
+struct ext4_new_group_input {
+       __u32 group;            /* Group number for this data */
+       __u64 block_bitmap;     /* Absolute block number of block bitmap */
+       __u64 inode_bitmap;     /* Absolute block number of inode bitmap */
+       __u64 inode_table;      /* Absolute block number of inode table start */
+       __u32 blocks_count;     /* Total number of blocks in this group */
+       __u16 reserved_blocks;  /* Number of reserved blocks in this group */
+       __u16 unused;
+};
+
+#if defined(__KERNEL__) && defined(CONFIG_COMPAT)
+struct compat_ext4_new_group_input {
+       u32 group;
+       compat_u64 block_bitmap;
+       compat_u64 inode_bitmap;
+       compat_u64 inode_table;
+       u32 blocks_count;
+       u16 reserved_blocks;
+       u16 unused;
+};
+#endif
+
+/* The struct ext4_new_group_input in kernel space, with free_blocks_count */
+struct ext4_new_group_data {
+       __u32 group;
+       __u64 block_bitmap;
+       __u64 inode_bitmap;
+       __u64 inode_table;
+       __u32 blocks_count;
+       __u16 reserved_blocks;
+       __u16 unused;
+       __u32 free_blocks_count;
+};
+
+/* Indexes used to index group tables in ext4_new_group_data */
+enum {
+       BLOCK_BITMAP = 0,       /* block bitmap */
+       INODE_BITMAP,           /* inode bitmap */
+       INODE_TABLE,            /* inode tables */
+       GROUP_TABLE_COUNT,
+};
+
+/*
+ * Flags used by ext4_map_blocks()
+ */
+       /* Allocate any needed blocks and/or convert an unwritten
+          extent to be an initialized ext4 */
+#define EXT4_GET_BLOCKS_CREATE                 0x0001
+       /* Request the creation of an unwritten extent */
+#define EXT4_GET_BLOCKS_UNWRIT_EXT             0x0002
+#define EXT4_GET_BLOCKS_CREATE_UNWRIT_EXT      (EXT4_GET_BLOCKS_UNWRIT_EXT|\
+                                                EXT4_GET_BLOCKS_CREATE)
+       /* Caller is from the delayed allocation writeout path
+        * finally doing the actual allocation of delayed blocks */
+#define EXT4_GET_BLOCKS_DELALLOC_RESERVE       0x0004
+       /* caller is from the direct IO path, request to creation of an
+       unwritten extents if not allocated, split the unwritten
+       extent if blocks has been preallocated already*/
+#define EXT4_GET_BLOCKS_PRE_IO                 0x0008
+#define EXT4_GET_BLOCKS_CONVERT                        0x0010
+#define EXT4_GET_BLOCKS_IO_CREATE_EXT          (EXT4_GET_BLOCKS_PRE_IO|\
+                                        EXT4_GET_BLOCKS_CREATE_UNWRIT_EXT)
+       /* Convert extent to initialized after IO complete */
+#define EXT4_GET_BLOCKS_IO_CONVERT_EXT         (EXT4_GET_BLOCKS_CONVERT|\
+                                        EXT4_GET_BLOCKS_CREATE_UNWRIT_EXT)
+       /* Eventual metadata allocation (due to growing extent tree)
+        * should not fail, so try to use reserved blocks for that.*/
+#define EXT4_GET_BLOCKS_METADATA_NOFAIL                0x0020
+       /* Don't normalize allocation size (used for fallocate) */
+#define EXT4_GET_BLOCKS_NO_NORMALIZE           0x0040
+       /* Request will not result in inode size update (user for fallocate) */
+#define EXT4_GET_BLOCKS_KEEP_SIZE              0x0080
+       /* Do not take i_data_sem locking in ext4_map_blocks */
+#define EXT4_GET_BLOCKS_NO_LOCK                        0x0100
+       /* Convert written extents to unwritten */
+#define EXT4_GET_BLOCKS_CONVERT_UNWRITTEN      0x0200
+
+/*
+ * The bit position of these flags must not overlap with any of the
+ * EXT4_GET_BLOCKS_*.  They are used by ext4_find_extent(),
+ * read_extent_tree_block(), ext4_split_extent_at(),
+ * ext4_ext_insert_extent(), and ext4_ext_create_new_leaf().
+ * EXT4_EX_NOCACHE is used to indicate that the we shouldn't be
+ * caching the extents when reading from the extent tree while a
+ * truncate or punch hole operation is in progress.
+ */
+#define EXT4_EX_NOCACHE                                0x40000000
+#define EXT4_EX_FORCE_CACHE                    0x20000000
+
+/*
+ * Flags used by ext4_free_blocks
+ */
+#define EXT4_FREE_BLOCKS_METADATA      0x0001
+#define EXT4_FREE_BLOCKS_FORGET                0x0002
+#define EXT4_FREE_BLOCKS_VALIDATED     0x0004
+#define EXT4_FREE_BLOCKS_NO_QUOT_UPDATE        0x0008
+#define EXT4_FREE_BLOCKS_NOFREE_FIRST_CLUSTER  0x0010
+#define EXT4_FREE_BLOCKS_NOFREE_LAST_CLUSTER   0x0020
+
+/* Encryption algorithms */
+#define EXT4_ENCRYPTION_MODE_INVALID           0
+#define EXT4_ENCRYPTION_MODE_AES_256_XTS       1
+#define EXT4_ENCRYPTION_MODE_AES_256_GCM       2
+#define EXT4_ENCRYPTION_MODE_AES_256_CBC       3
+#define EXT4_ENCRYPTION_MODE_AES_256_CTS       4
+
+#include "ext4_crypto.h"
+
+/*
+ * ioctl commands
+ */
+#define        EXT4_IOC_GETFLAGS               FS_IOC_GETFLAGS
+#define        EXT4_IOC_SETFLAGS               FS_IOC_SETFLAGS
+#define        EXT4_IOC_GETVERSION             _IOR('f', 3, long)
+#define        EXT4_IOC_SETVERSION             _IOW('f', 4, long)
+#define        EXT4_IOC_GETVERSION_OLD         FS_IOC_GETVERSION
+#define        EXT4_IOC_SETVERSION_OLD         FS_IOC_SETVERSION
+#define EXT4_IOC_GETRSVSZ              _IOR('f', 5, long)
+#define EXT4_IOC_SETRSVSZ              _IOW('f', 6, long)
+#define EXT4_IOC_GROUP_EXTEND          _IOW('f', 7, unsigned long)
+#define EXT4_IOC_GROUP_ADD             _IOW('f', 8, struct ext4_new_group_input)
+#define EXT4_IOC_MIGRATE               _IO('f', 9)
+ /* note ioctl 10 reserved for an early version of the FIEMAP ioctl */
+ /* note ioctl 11 reserved for filesystem-independent FIEMAP ioctl */
+#define EXT4_IOC_ALLOC_DA_BLKS         _IO('f', 12)
+#define EXT4_IOC_MOVE_EXT              _IOWR('f', 15, struct move_extent)
+#define EXT4_IOC_RESIZE_FS             _IOW('f', 16, __u64)
+#define EXT4_IOC_SWAP_BOOT             _IO('f', 17)
+#define EXT4_IOC_PRECACHE_EXTENTS      _IO('f', 18)
+#define EXT4_IOC_SET_ENCRYPTION_POLICY _IOR('f', 19, struct ext4_encryption_policy)
+#define EXT4_IOC_GET_ENCRYPTION_PWSALT _IOW('f', 20, __u8[16])
+#define EXT4_IOC_GET_ENCRYPTION_POLICY _IOW('f', 21, struct ext4_encryption_policy)
+
+#if defined(__KERNEL__) && defined(CONFIG_COMPAT)
+/*
+ * ioctl commands in 32 bit emulation
+ */
+#define EXT4_IOC32_GETFLAGS            FS_IOC32_GETFLAGS
+#define EXT4_IOC32_SETFLAGS            FS_IOC32_SETFLAGS
+#define EXT4_IOC32_GETVERSION          _IOR('f', 3, int)
+#define EXT4_IOC32_SETVERSION          _IOW('f', 4, int)
+#define EXT4_IOC32_GETRSVSZ            _IOR('f', 5, int)
+#define EXT4_IOC32_SETRSVSZ            _IOW('f', 6, int)
+#define EXT4_IOC32_GROUP_EXTEND                _IOW('f', 7, unsigned int)
+#define EXT4_IOC32_GROUP_ADD           _IOW('f', 8, struct compat_ext4_new_group_input)
+#define EXT4_IOC32_GETVERSION_OLD      FS_IOC32_GETVERSION
+#define EXT4_IOC32_SETVERSION_OLD      FS_IOC32_SETVERSION
+#endif
+
+/* Max physical block we can address w/o extents */
+#define EXT4_MAX_BLOCK_FILE_PHYS       0xFFFFFFFF
+
+/*
+ * Structure of an inode on the disk
+ */
+struct ext4_inode {
+       __le16  i_mode;         /* File mode */
+       __le16  i_uid;          /* Low 16 bits of Owner Uid */
+       __le32  i_size_lo;      /* Size in bytes */
+       __le32  i_atime;        /* Access time */
+       __le32  i_ctime;        /* Inode Change time */
+       __le32  i_mtime;        /* Modification time */
+       __le32  i_dtime;        /* Deletion Time */
+       __le16  i_gid;          /* Low 16 bits of Group Id */
+       __le16  i_links_count;  /* Links count */
+       __le32  i_blocks_lo;    /* Blocks count */
+       __le32  i_flags;        /* File flags */
+       union {
+               struct {
+                       __le32  l_i_version;
+               } linux1;
+               struct {
+                       __u32  h_i_translator;
+               } hurd1;
+               struct {
+                       __u32  m_i_reserved1;
+               } masix1;
+       } osd1;                         /* OS dependent 1 */
+       __le32  i_block[EXT4_N_BLOCKS];/* Pointers to blocks */
+       __le32  i_generation;   /* File version (for NFS) */
+       __le32  i_file_acl_lo;  /* File ACL */
+       __le32  i_size_high;
+       __le32  i_obso_faddr;   /* Obsoleted fragment address */
+       union {
+               struct {
+                       __le16  l_i_blocks_high; /* were l_i_reserved1 */
+                       __le16  l_i_file_acl_high;
+                       __le16  l_i_uid_high;   /* these 2 fields */
+                       __le16  l_i_gid_high;   /* were reserved2[0] */
+                       __le16  l_i_checksum_lo;/* crc32c(uuid+inum+inode) LE */
+                       __le16  l_i_reserved;
+               } linux2;
+               struct {
+                       __le16  h_i_reserved1;  /* Obsoleted fragment number/size which are removed in ext4 */
+                       __u16   h_i_mode_high;
+                       __u16   h_i_uid_high;
+                       __u16   h_i_gid_high;
+                       __u32   h_i_author;
+               } hurd2;
+               struct {
+                       __le16  h_i_reserved1;  /* Obsoleted fragment number/size which are removed in ext4 */
+                       __le16  m_i_file_acl_high;
+                       __u32   m_i_reserved2[2];
+               } masix2;
+       } osd2;                         /* OS dependent 2 */
+       __le16  i_extra_isize;
+       __le16  i_checksum_hi;  /* crc32c(uuid+inum+inode) BE */
+       __le32  i_ctime_extra;  /* extra Change time      (nsec << 2 | epoch) */
+       __le32  i_mtime_extra;  /* extra Modification time(nsec << 2 | epoch) */
+       __le32  i_atime_extra;  /* extra Access time      (nsec << 2 | epoch) */
+       __le32  i_crtime;       /* File Creation time */
+       __le32  i_crtime_extra; /* extra FileCreationtime (nsec << 2 | epoch) */
+       __le32  i_version_hi;   /* high 32 bits for 64-bit version */
+};
+
+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))                   \
+
+static inline __le32 ext4_encode_extra_time(struct timespec *time)
+{
+       return cpu_to_le32((sizeof(time->tv_sec) > 4 ?
+                          (time->tv_sec >> 32) & EXT4_EPOCH_MASK : 0) |
+                          ((time->tv_nsec << EXT4_EPOCH_BITS) & EXT4_NSEC_MASK));
+}
+
+static inline void ext4_decode_extra_time(struct timespec *time, __le32 extra)
+{
+       if (sizeof(time->tv_sec) > 4)
+              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 {                                                                          \
+       (raw_inode)->xtime = cpu_to_le32((inode)->xtime.tv_sec);               \
+       if (EXT4_FITS_IN_INODE(raw_inode, EXT4_I(inode), xtime ## _extra))     \
+               (raw_inode)->xtime ## _extra =                                 \
+                               ext4_encode_extra_time(&(inode)->xtime);       \
+} while (0)
+
+#define EXT4_EINODE_SET_XTIME(xtime, einode, raw_inode)                               \
+do {                                                                          \
+       if (EXT4_FITS_IN_INODE(raw_inode, einode, xtime))                      \
+               (raw_inode)->xtime = cpu_to_le32((einode)->xtime.tv_sec);      \
+       if (EXT4_FITS_IN_INODE(raw_inode, einode, xtime ## _extra))            \
+               (raw_inode)->xtime ## _extra =                                 \
+                               ext4_encode_extra_time(&(einode)->xtime);      \
+} while (0)
+
+#define EXT4_INODE_GET_XTIME(xtime, inode, raw_inode)                         \
+do {                                                                          \
+       (inode)->xtime.tv_sec = (signed)le32_to_cpu((raw_inode)->xtime);       \
+       if (EXT4_FITS_IN_INODE(raw_inode, EXT4_I(inode), xtime ## _extra))     \
+               ext4_decode_extra_time(&(inode)->xtime,                        \
+                                      raw_inode->xtime ## _extra);            \
+       else                                                                   \
+               (inode)->xtime.tv_nsec = 0;                                    \
+} while (0)
+
+#define EXT4_EINODE_GET_XTIME(xtime, einode, raw_inode)                               \
+do {                                                                          \
+       if (EXT4_FITS_IN_INODE(raw_inode, einode, xtime))                      \
+               (einode)->xtime.tv_sec =                                       \
+                       (signed)le32_to_cpu((raw_inode)->xtime);               \
+       else                                                                   \
+               (einode)->xtime.tv_sec = 0;                                    \
+       if (EXT4_FITS_IN_INODE(raw_inode, einode, xtime ## _extra))            \
+               ext4_decode_extra_time(&(einode)->xtime,                       \
+                                      raw_inode->xtime ## _extra);            \
+       else                                                                   \
+               (einode)->xtime.tv_nsec = 0;                                   \
+} while (0)
+
+#define i_disk_version osd1.linux1.l_i_version
+
+#if defined(__KERNEL__) || defined(__linux__)
+#define i_reserved1    osd1.linux1.l_i_reserved1
+#define i_file_acl_high        osd2.linux2.l_i_file_acl_high
+#define i_blocks_high  osd2.linux2.l_i_blocks_high
+#define i_uid_low      i_uid
+#define i_gid_low      i_gid
+#define i_uid_high     osd2.linux2.l_i_uid_high
+#define i_gid_high     osd2.linux2.l_i_gid_high
+#define i_checksum_lo  osd2.linux2.l_i_checksum_lo
+
+#elif defined(__GNU__)
+
+#define i_translator   osd1.hurd1.h_i_translator
+#define i_uid_high     osd2.hurd2.h_i_uid_high
+#define i_gid_high     osd2.hurd2.h_i_gid_high
+#define i_author       osd2.hurd2.h_i_author
+
+#elif defined(__masix__)
+
+#define i_reserved1    osd1.masix1.m_i_reserved1
+#define i_file_acl_high        osd2.masix2.m_i_file_acl_high
+#define i_reserved2    osd2.masix2.m_i_reserved2
+
+#endif /* defined(__KERNEL__) || defined(__linux__) */
+
+#include "extents_status.h"
+
+/*
+ * fourth extended file system inode data in memory
+ */
+struct ext4_inode_info {
+       __le32  i_data[15];     /* unconverted */
+       __u32   i_dtime;
+       ext4_fsblk_t    i_file_acl;
+
+       /*
+        * i_block_group is the number of the block group which contains
+        * this file's inode.  Constant across the lifetime of the inode,
+        * it is ued for making block allocation decisions - we try to
+        * place a file's data blocks near its inode block, and new inodes
+        * near to their parent directory's inode.
+        */
+       ext4_group_t    i_block_group;
+       ext4_lblk_t     i_dir_start_lookup;
+#if (BITS_PER_LONG < 64)
+       unsigned long   i_state_flags;          /* Dynamic state flags */
+#endif
+       unsigned long   i_flags;
+
+       /*
+        * Extended attributes can be read independently of the main file
+        * data. Taking i_mutex even when reading would cause contention
+        * between readers of EAs and writers of regular file data, so
+        * instead we synchronize on xattr_sem when reading or changing
+        * EAs.
+        */
+       struct rw_semaphore xattr_sem;
+
+       struct list_head i_orphan;      /* unlinked but open inodes */
+
+       /*
+        * i_disksize keeps track of what the inode size is ON DISK, not
+        * in memory.  During truncate, i_size is set to the new size by
+        * the VFS prior to calling ext4_truncate(), but the filesystem won't
+        * set i_disksize to 0 until the truncate is actually under way.
+        *
+        * The intent is that i_disksize always represents the blocks which
+        * are used by this file.  This allows recovery to restart truncate
+        * on orphans if we crash during truncate.  We actually write i_disksize
+        * into the on-disk inode when writing inodes out, instead of i_size.
+        *
+        * The only time when i_disksize and i_size may be different is when
+        * a truncate is in progress.  The only things which change i_disksize
+        * are ext4_get_block (growth) and ext4_truncate (shrinkth).
+        */
+       loff_t  i_disksize;
+
+       /*
+        * i_data_sem is for serialising ext4_truncate() against
+        * ext4_getblock().  In the 2.4 ext2 design, great chunks of inode's
+        * data tree are chopped off during truncate. We can't do that in
+        * ext4 because whenever we perform intermediate commits during
+        * truncate, the inode and all the metadata blocks *must* be in a
+        * consistent state which allows truncation of the orphans to restart
+        * during recovery.  Hence we must fix the get_block-vs-truncate race
+        * by other means, so we have i_data_sem.
+        */
+       struct rw_semaphore i_data_sem;
+       struct inode vfs_inode;
+       struct jbd2_inode *jinode;
+
+       spinlock_t i_raw_lock;  /* protects updates to the raw inode */
+
+       /*
+        * File creation time. Its function is same as that of
+        * struct timespec i_{a,c,m}time in the generic inode.
+        */
+       struct timespec i_crtime;
+
+       /* mballoc */
+       struct list_head i_prealloc_list;
+       spinlock_t i_prealloc_lock;
+
+       /* extents status tree */
+       struct ext4_es_tree i_es_tree;
+       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, these refer to clusters rather than blocks */
+       unsigned int i_reserved_data_blocks;
+       unsigned int i_reserved_meta_blocks;
+       unsigned int i_allocated_meta_blocks;
+       ext4_lblk_t i_da_metadata_calc_last_lblock;
+       int i_da_metadata_calc_len;
+
+       /* on-disk additional length */
+       __u16 i_extra_isize;
+       char i_crypt_policy_flags;
+
+       /* 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;
+       /*
+        * Completed IOs that need unwritten extents handling and don't have
+        * transaction reserved
+        */
+       atomic_t i_ioend_count; /* Number of outstanding io_end structs */
+       atomic_t i_unwritten; /* Nr. of inflight conversions pending */
+       struct work_struct i_rsv_conversion_work;
+
+       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;
+
+#ifdef CONFIG_EXT4_FS_ENCRYPTION
+       /* Encryption params */
+       struct ext4_encryption_key i_encryption_key;
+#endif
+};
+
+/*
+ * 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 */
+
+/*
+ * 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_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                 0x00200 /* Direct Access */
+#else
+#define EXT4_MOUNT_DAX                 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               0x80000 /* Some quota option set */
+#define EXT4_MOUNT_USRQUOTA            0x100000 /* "old" user quota */
+#define EXT4_MOUNT_GRPQUOTA            0x200000 /* "old" group quota */
+#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_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 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 ext4_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
+
+/*
+ * Structure of the super block
+ */
+struct ext4_super_block {
+/*00*/ __le32  s_inodes_count;         /* Inodes count */
+       __le32  s_blocks_count_lo;      /* Blocks count */
+       __le32  s_r_blocks_count_lo;    /* Reserved blocks count */
+       __le32  s_free_blocks_count_lo; /* Free blocks count */
+/*10*/ __le32  s_free_inodes_count;    /* Free inodes count */
+       __le32  s_first_data_block;     /* First Data Block */
+       __le32  s_log_block_size;       /* Block size */
+       __le32  s_log_cluster_size;     /* Allocation cluster size */
+/*20*/ __le32  s_blocks_per_group;     /* # Blocks per group */
+       __le32  s_clusters_per_group;   /* # Clusters per group */
+       __le32  s_inodes_per_group;     /* # Inodes per group */
+       __le32  s_mtime;                /* Mount time */
+/*30*/ __le32  s_wtime;                /* Write time */
+       __le16  s_mnt_count;            /* Mount count */
+       __le16  s_max_mnt_count;        /* Maximal mount count */
+       __le16  s_magic;                /* Magic signature */
+       __le16  s_state;                /* File system state */
+       __le16  s_errors;               /* Behaviour when detecting errors */
+       __le16  s_minor_rev_level;      /* minor revision level */
+/*40*/ __le32  s_lastcheck;            /* time of last check */
+       __le32  s_checkinterval;        /* max. time between checks */
+       __le32  s_creator_os;           /* OS */
+       __le32  s_rev_level;            /* Revision level */
+/*50*/ __le16  s_def_resuid;           /* Default uid for reserved blocks */
+       __le16  s_def_resgid;           /* Default gid for reserved blocks */
+       /*
+        * These fields are for EXT4_DYNAMIC_REV superblocks only.
+        *
+        * Note: the difference between the compatible feature set and
+        * the incompatible feature set is that if there is a bit set
+        * in the incompatible feature set that the kernel doesn't
+        * know about, it should refuse to mount the filesystem.
+        *
+        * e2fsck's requirements are more strict; if it doesn't know
+        * about a feature in either the compatible or incompatible
+        * feature set, it must abort and not try to meddle with
+        * things it doesn't understand...
+        */
+       __le32  s_first_ino;            /* First non-reserved inode */
+       __le16  s_inode_size;           /* size of inode structure */
+       __le16  s_block_group_nr;       /* block group # of this superblock */
+       __le32  s_feature_compat;       /* compatible feature set */
+/*60*/ __le32  s_feature_incompat;     /* incompatible feature set */
+       __le32  s_feature_ro_compat;    /* readonly-compatible feature set */
+/*68*/ __u8    s_uuid[16];             /* 128-bit uuid for volume */
+/*78*/ char    s_volume_name[16];      /* volume name */
+/*88*/ char    s_last_mounted[64];     /* directory where last mounted */
+/*C8*/ __le32  s_algorithm_usage_bitmap; /* For compression */
+       /*
+        * Performance hints.  Directory preallocation should only
+        * happen if the EXT4_FEATURE_COMPAT_DIR_PREALLOC flag is on.
+        */
+       __u8    s_prealloc_blocks;      /* Nr of blocks to try to preallocate*/
+       __u8    s_prealloc_dir_blocks;  /* Nr to preallocate for dirs */
+       __le16  s_reserved_gdt_blocks;  /* Per group desc for online growth */
+       /*
+        * Journaling support valid if EXT4_FEATURE_COMPAT_HAS_JOURNAL set.
+        */
+/*D0*/ __u8    s_journal_uuid[16];     /* uuid of journal superblock */
+/*E0*/ __le32  s_journal_inum;         /* inode number of journal file */
+       __le32  s_journal_dev;          /* device number of journal file */
+       __le32  s_last_orphan;          /* start of list of inodes to delete */
+       __le32  s_hash_seed[4];         /* HTREE hash seed */
+       __u8    s_def_hash_version;     /* Default hash version to use */
+       __u8    s_jnl_backup_type;
+       __le16  s_desc_size;            /* size of group descriptor */
+/*100*/        __le32  s_default_mount_opts;
+       __le32  s_first_meta_bg;        /* First metablock block group */
+       __le32  s_mkfs_time;            /* When the filesystem was created */
+       __le32  s_jnl_blocks[17];       /* Backup of the journal inode */
+       /* 64bit support valid if EXT4_FEATURE_COMPAT_64BIT */
+/*150*/        __le32  s_blocks_count_hi;      /* Blocks count */
+       __le32  s_r_blocks_count_hi;    /* Reserved blocks count */
+       __le32  s_free_blocks_count_hi; /* Free blocks count */
+       __le16  s_min_extra_isize;      /* All inodes have at least # bytes */
+       __le16  s_want_extra_isize;     /* New inodes should reserve # bytes */
+       __le32  s_flags;                /* Miscellaneous flags */
+       __le16  s_raid_stride;          /* RAID stride */
+       __le16  s_mmp_update_interval;  /* # seconds to wait in MMP checking */
+       __le64  s_mmp_block;            /* Block for multi-mount protection */
+       __le32  s_raid_stripe_width;    /* blocks on all data disks (N*stride)*/
+       __u8    s_log_groups_per_flex;  /* FLEX_BG group size */
+       __u8    s_checksum_type;        /* metadata checksum algorithm used */
+       __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]; /* function where the error happened */
+       __le32  s_first_error_line;     /* line number where error happened */
+       __le32  s_last_error_time;      /* most recent time of an error */
+       __le32  s_last_error_ino;       /* inode involved in last error */
+       __le32  s_last_error_line;      /* line number where error happened */
+       __le64  s_last_error_block;     /* block involved of last error */
+       __u8    s_last_error_func[32];  /* function where the error happened */
+#define EXT4_S_ERR_END offsetof(struct ext4_super_block, s_mount_opts)
+       __u8    s_mount_opts[64];
+       __le32  s_usr_quota_inum;       /* inode for tracking user quota */
+       __le32  s_grp_quota_inum;       /* inode for tracking group quota */
+       __le32  s_overhead_clusters;    /* overhead blocks/clusters in fs */
+       __le32  s_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_reserved[100];        /* 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__
+
+/*
+ * run-time mount flags
+ */
+#define EXT4_MF_MNTDIR_SAMPLED         0x0001
+#define EXT4_MF_FS_ABORTED             0x0002  /* Fatal error detected */
+#define EXT4_MF_TEST_DUMMY_ENCRYPTION  0x0004
+
+#ifdef CONFIG_EXT4_FS_ENCRYPTION
+#define DUMMY_ENCRYPTION_ENABLED(sbi) (unlikely((sbi)->s_mount_flags & \
+                                               EXT4_MF_TEST_DUMMY_ENCRYPTION))
+#else
+#define DUMMY_ENCRYPTION_ENABLED(sbi) (0)
+#endif
+
+/* Number of quota types we support */
+#define EXT4_MAXQUOTAS 2
+
+/*
+ * 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 **s_group_desc;
+       unsigned int s_mount_opt;
+       unsigned int s_mount_opt2;
+       unsigned int 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;
+       spinlock_t s_next_gen_lock;
+       u32 s_next_generation;
+       u32 s_hash_seed[4];
+       int s_def_hash_version;
+       int s_hash_unsigned;    /* 3 if hash should be signed, 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 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;
+
+       /* Journaling */
+       struct journal_s *s_journal;
+       struct list_head s_orphan;
+       struct mutex s_orphan_lock;
+       unsigned long s_resize_flags;           /* Flags indicating if there
+                                                  is a resizer */
+       unsigned long s_commit_interval;
+       u32 s_max_batch_time;
+       u32 s_min_batch_time;
+       struct block_device *journal_bdev;
+#ifdef CONFIG_QUOTA
+       char *s_qf_names[EXT4_MAXQUOTAS];       /* Names of quota files with journalled quota */
+       int s_jquota_fmt;                       /* Format of quota to use */
+#endif
+       unsigned int s_want_extra_isize; /* New inodes should reserve # bytes */
+       struct rb_root 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 ***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;
+
+       /* tunables */
+       unsigned long s_stripe;
+       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_max_dir_size_kb;
+       /* where last allocation was done - for stream allocation */
+       unsigned long s_mb_last_group;
+       unsigned long s_mb_last_start;
+
+       /* 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_goals;   /* goal hits */
+       atomic_t s_bal_breaks;  /* too long searches */
+       atomic_t s_bal_2orders; /* 2^order hits */
+       spinlock_t s_bal_lock;
+       unsigned long s_mb_buddies_generated;
+       unsigned long long 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 *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. */
+       atomic_t 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_mb_cache;
+       spinlock_t s_es_lock ____cacheline_aligned_in_smp;
+
+       /* Ratelimit ext4 messages. */
+       struct ratelimit_state s_err_ratelimit_state;
+       struct ratelimit_state s_warning_ratelimit_state;
+       struct ratelimit_state s_msg_ratelimit_state;
+
+#ifdef CONFIG_EXT4_FS_ENCRYPTION
+       /* Encryption */
+       uint32_t s_file_encryption_mode;
+       uint32_t s_dir_encryption_mode;
+#endif
+};
+
+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 struct timespec ext4_current_time(struct inode *inode)
+{
+       return (inode->i_sb->s_time_gran < NSEC_PER_SEC) ?
+               current_fs_time(inode->i_sb) : CURRENT_TIME_SEC;
+}
+
+static inline int ext4_valid_inum(struct super_block *sb, unsigned long ino)
+{
+       return ino == EXT4_ROOT_INO ||
+               ino == EXT4_USR_QUOTA_INO ||
+               ino == EXT4_GRP_QUOTA_INO ||
+               ino == EXT4_BOOT_LOADER_INO ||
+               ino == EXT4_JOURNAL_INO ||
+               ino == EXT4_RESIZE_INO ||
+               (ino >= EXT4_FIRST_INO(sb) &&
+                ino <= le32_to_cpu(EXT4_SB(sb)->s_es->s_inodes_count));
+}
+
+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 ext4_io_end_t *ext4_inode_aio(struct inode *inode)
+{
+       return inode->i_private;
+}
+
+static inline void ext4_inode_aio_set(struct inode *inode, ext4_io_end_t *io)
+{
+       inode->i_private = io;
+}
+
+/*
+ * 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_DIO_UNWRITTEN,       /* need convert on dio done*/
+       EXT4_STATE_NEWENTRY,            /* File just added to dir */
+       EXT4_STATE_DIOREAD_LOCK,        /* Disable support for dio read
+                                          nolocking */
+       EXT4_STATE_MAY_INLINE_DATA,     /* may have in-inode data */
+       EXT4_STATE_ORDERED_MODE,        /* data=ordered mode */
+       EXT4_STATE_EXT_PRECACHED,       /* extents have been precached */
+};
+
+#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
+
+/*
+ * Returns true if the inode is inode is encrypted
+ */
+static inline int ext4_encrypted_inode(struct inode *inode)
+{
+#ifdef CONFIG_EXT4_FS_ENCRYPTION
+       return ext4_test_inode_flag(inode, EXT4_INODE_ENCRYPT);
+#else
+       return 0;
+#endif
+}
+
+#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_CURRENT_REV       EXT4_GOOD_OLD_REV
+#define EXT4_MAX_SUPP_REV      EXT4_DYNAMIC_REV
+
+#define EXT4_GOOD_OLD_INODE_SIZE 128
+
+/*
+ * Feature set definitions
+ */
+
+#define EXT4_HAS_COMPAT_FEATURE(sb,mask)                       \
+       ((EXT4_SB(sb)->s_es->s_feature_compat & cpu_to_le32(mask)) != 0)
+#define EXT4_HAS_RO_COMPAT_FEATURE(sb,mask)                    \
+       ((EXT4_SB(sb)->s_es->s_feature_ro_compat & cpu_to_le32(mask)) != 0)
+#define EXT4_HAS_INCOMPAT_FEATURE(sb,mask)                     \
+       ((EXT4_SB(sb)->s_es->s_feature_incompat & cpu_to_le32(mask)) != 0)
+#define EXT4_SET_COMPAT_FEATURE(sb,mask)                       \
+       EXT4_SB(sb)->s_es->s_feature_compat |= cpu_to_le32(mask)
+#define EXT4_SET_RO_COMPAT_FEATURE(sb,mask)                    \
+       EXT4_SB(sb)->s_es->s_feature_ro_compat |= cpu_to_le32(mask)
+#define EXT4_SET_INCOMPAT_FEATURE(sb,mask)                     \
+       EXT4_SB(sb)->s_es->s_feature_incompat |= cpu_to_le32(mask)
+#define EXT4_CLEAR_COMPAT_FEATURE(sb,mask)                     \
+       EXT4_SB(sb)->s_es->s_feature_compat &= ~cpu_to_le32(mask)
+#define EXT4_CLEAR_RO_COMPAT_FEATURE(sb,mask)                  \
+       EXT4_SB(sb)->s_es->s_feature_ro_compat &= ~cpu_to_le32(mask)
+#define EXT4_CLEAR_INCOMPAT_FEATURE(sb,mask)                   \
+       EXT4_SB(sb)->s_es->s_feature_incompat &= ~cpu_to_le32(mask)
+
+#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
+
+#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_INCOMPAT_COMPRESSION      0x0001
+#define EXT4_FEATURE_INCOMPAT_FILETYPE         0x0002
+#define EXT4_FEATURE_INCOMPAT_RECOVER          0x0004 /* Needs recovery */
+#define EXT4_FEATURE_INCOMPAT_JOURNAL_DEV      0x0008 /* Journal device */
+#define EXT4_FEATURE_INCOMPAT_META_BG          0x0010
+#define EXT4_FEATURE_INCOMPAT_EXTENTS          0x0040 /* extents support */
+#define EXT4_FEATURE_INCOMPAT_64BIT            0x0080
+#define EXT4_FEATURE_INCOMPAT_MMP               0x0100
+#define EXT4_FEATURE_INCOMPAT_FLEX_BG          0x0200
+#define EXT4_FEATURE_INCOMPAT_EA_INODE         0x0400 /* EA in inode */
+#define EXT4_FEATURE_INCOMPAT_DIRDATA          0x1000 /* data in dirent */
+#define EXT4_FEATURE_INCOMPAT_BG_USE_META_CSUM 0x2000 /* use crc32c for bg */
+#define EXT4_FEATURE_INCOMPAT_LARGEDIR         0x4000 /* >2GB or 3-lvl htree */
+#define EXT4_FEATURE_INCOMPAT_INLINE_DATA      0x8000 /* data in inode */
+#define EXT4_FEATURE_INCOMPAT_ENCRYPT          0x10000
+
+#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       EXT2_FEATURE_COMPAT_EXT_ATTR
+#define EXT4_FEATURE_INCOMPAT_SUPP     (EXT4_FEATURE_INCOMPAT_FILETYPE| \
+                                        EXT4_FEATURE_INCOMPAT_RECOVER| \
+                                        EXT4_FEATURE_INCOMPAT_META_BG| \
+                                        EXT4_FEATURE_INCOMPAT_EXTENTS| \
+                                        EXT4_FEATURE_INCOMPAT_64BIT| \
+                                        EXT4_FEATURE_INCOMPAT_FLEX_BG| \
+                                        EXT4_FEATURE_INCOMPAT_MMP | \
+                                        EXT4_FEATURE_INCOMPAT_INLINE_DATA | \
+                                        EXT4_FEATURE_INCOMPAT_ENCRYPT)
+#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)
+
+/*
+ * Default values for user and/or group using reserved blocks
+ */
+#define        EXT4_DEF_RESUID         0
+#define        EXT4_DEF_RESGID         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
+
+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 */
+};
+
+/*
+ * 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;
+       char    name[EXT4_NAME_LEN];    /* File name */
+};
+
+/*
+ * 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_DIR_REC_LEN(name_len)     (((name_len) + 8 + EXT4_DIR_ROUND) & \
+                                        ~EXT4_DIR_ROUND)
+#define EXT4_MAX_REC_LEN               ((1<<16)-1)
+
+/*
+ * 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_CACHE_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)
+{
+       if ((len > blocksize) || (blocksize > (1 << 18)) || (len & 3))
+               BUG();
+#if (PAGE_CACHE_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_COMPAT_FEATURE(dir->i_sb, \
+                                     EXT4_FEATURE_COMPAT_DIR_INDEX) && \
+                   ext4_test_inode_flag((dir), EXT4_INODE_INDEX))
+#define EXT4_DIR_LINK_MAX(dir) (!is_dx(dir) && (dir)->i_nlink >= EXT4_LINK_MAX)
+#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
+
+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;
+       int err;
+
+       BUG_ON(crypto_shash_descsize(sbi->s_chksum_driver)!=sizeof(desc.ctx));
+
+       desc.shash.tfm = sbi->s_chksum_driver;
+       desc.shash.flags = 0;
+       *(u32 *)desc.ctx = crc;
+
+       err = crypto_shash_update(&desc.shash, address, length);
+       BUG_ON(err);
+
+       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
+
+
+/*
+ * 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);
+}
+
+/*
+ * 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))
+
+/*
+ * 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;
+};
+
+struct ext4_li_request {
+       struct super_block      *lr_super;
+       struct ext4_sb_info     *lr_sbi;
+       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);
+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 *);
+
+/* crypto_policy.c */
+int ext4_is_child_context_consistent_with_parent(struct inode *parent,
+                                                struct inode *child);
+int ext4_inherit_context(struct inode *parent, struct inode *child);
+void ext4_to_hex(char *dst, char *src, size_t src_size);
+int ext4_process_policy(const struct ext4_encryption_policy *policy,
+                       struct inode *inode);
+int ext4_get_policy(struct inode *inode,
+                   struct ext4_encryption_policy *policy);
+
+/* crypto.c */
+bool ext4_valid_contents_enc_mode(uint32_t mode);
+uint32_t ext4_validate_encryption_key_size(uint32_t mode, uint32_t size);
+extern struct workqueue_struct *ext4_read_workqueue;
+struct ext4_crypto_ctx *ext4_get_crypto_ctx(struct inode *inode);
+void ext4_release_crypto_ctx(struct ext4_crypto_ctx *ctx);
+void ext4_restore_control_page(struct page *data_page);
+struct page *ext4_encrypt(struct inode *inode,
+                         struct page *plaintext_page);
+int ext4_decrypt(struct ext4_crypto_ctx *ctx, struct page *page);
+int ext4_decrypt_one(struct inode *inode, struct page *page);
+int ext4_encrypted_zeroout(struct inode *inode, struct ext4_extent *ex);
+
+#ifdef CONFIG_EXT4_FS_ENCRYPTION
+int ext4_init_crypto(void);
+void ext4_exit_crypto(void);
+static inline int ext4_sb_has_crypto(struct super_block *sb)
+{
+       return EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_ENCRYPT);
+}
+#else
+static inline int ext4_init_crypto(void) { return 0; }
+static inline void ext4_exit_crypto(void) { }
+static inline int ext4_sb_has_crypto(struct super_block *sb)
+{
+       return 0;
+}
+#endif
+
+/* crypto_fname.c */
+bool ext4_valid_filenames_enc_mode(uint32_t mode);
+u32 ext4_fname_crypto_round_up(u32 size, u32 blksize);
+int ext4_fname_crypto_alloc_buffer(struct ext4_fname_crypto_ctx *ctx,
+                                  u32 ilen, struct ext4_str *crypto_str);
+int _ext4_fname_disk_to_usr(struct ext4_fname_crypto_ctx *ctx,
+                           struct dx_hash_info *hinfo,
+                           const struct ext4_str *iname,
+                           struct ext4_str *oname);
+int ext4_fname_disk_to_usr(struct ext4_fname_crypto_ctx *ctx,
+                          struct dx_hash_info *hinfo,
+                          const struct ext4_dir_entry_2 *de,
+                          struct ext4_str *oname);
+int ext4_fname_usr_to_disk(struct ext4_fname_crypto_ctx *ctx,
+                          const struct qstr *iname,
+                          struct ext4_str *oname);
+int ext4_fname_usr_to_hash(struct ext4_fname_crypto_ctx *ctx,
+                          const struct qstr *iname,
+                          struct dx_hash_info *hinfo);
+int ext4_fname_crypto_namelen_on_disk(struct ext4_fname_crypto_ctx *ctx,
+                                     u32 namelen);
+int ext4_fname_match(struct ext4_fname_crypto_ctx *ctx, struct ext4_str *cstr,
+                    int len, const char * const name,
+                    struct ext4_dir_entry_2 *de);
+
+
+#ifdef CONFIG_EXT4_FS_ENCRYPTION
+void ext4_put_fname_crypto_ctx(struct ext4_fname_crypto_ctx **ctx);
+struct ext4_fname_crypto_ctx *ext4_get_fname_crypto_ctx(struct inode *inode,
+                                                       u32 max_len);
+void ext4_fname_crypto_free_buffer(struct ext4_str *crypto_str);
+#else
+static inline
+void ext4_put_fname_crypto_ctx(struct ext4_fname_crypto_ctx **ctx) { }
+static inline
+struct ext4_fname_crypto_ctx *ext4_get_fname_crypto_ctx(struct inode *inode,
+                                                       u32 max_len)
+{
+       return NULL;
+}
+static inline void ext4_fname_crypto_free_buffer(struct ext4_str *p) { }
+#endif
+
+
+/* crypto_key.c */
+int ext4_generate_encryption_key(struct inode *inode);
+
+#ifdef CONFIG_EXT4_FS_ENCRYPTION
+int ext4_has_encryption_key(struct inode *inode);
+#else
+static inline int ext4_has_encryption_key(struct inode *inode)
+{
+       return 0;
+}
+#endif
+
+
+/* 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 ext4_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,
+                            const char *name, int namelen,
+                            struct ext4_dir_entry_2 **dest_de);
+int ext4_insert_dentry(struct inode *dir,
+                       struct inode *inode,
+                       struct ext4_dir_entry_2 *de,
+                       int buf_size,
+                      const struct qstr *iname,
+                       const char *name, int namelen);
+static inline void ext4_update_dx_flag(struct inode *inode)
+{
+       if (!EXT4_HAS_COMPAT_FEATURE(inode->i_sb,
+                                    EXT4_FEATURE_COMPAT_DIR_INDEX))
+               ext4_clear_inode_flag(inode, EXT4_INODE_INDEX);
+}
+static 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_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_FILETYPE) ||
+           (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 char *name, int len, struct
+                         dx_hash_info *hinfo);
+
+/* ialloc.c */
+extern struct inode *__ext4_new_inode(handle_t *, struct inode *, umode_t,
+                                     const struct qstr *qstr, __u32 goal,
+                                     uid_t *owner, int handle_type,
+                                     unsigned int line_no, int nblocks);
+
+#define ext4_new_inode(handle, dir, mode, qstr, goal, owner) \
+       __ext4_new_inode((handle), (dir), (mode), (qstr), (goal), (owner), \
+                        0, 0, 0)
+#define ext4_new_inode_start_handle(dir, mode, qstr, goal, owner, \
+                                   type, nblocks)                  \
+       __ext4_new_inode(NULL, (dir), (mode), (qstr), (goal), (owner), \
+                        (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);
+
+/* mballoc.c */
+extern long ext4_mb_stats;
+extern long ext4_mb_max_to_scan;
+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 *);
+extern int __init ext4_init_mballoc(void);
+extern void ext4_exit_mballoc(void);
+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 *);
+
+/* inode.c */
+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_get_block_write(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 buffer_head *head,
+                          unsigned from,
+                          unsigned to,
+                          int *partial,
+                          int (*fn)(handle_t *handle,
+                                    struct buffer_head *bh));
+int do_journal_get_write_access(handle_t *handle,
+                               struct buffer_head *bh);
+#define FALL_BACK_TO_NONDELALLOC 1
+#define CONVERT_INLINE_DATA     2
+
+extern struct inode *ext4_iget(struct super_block *, unsigned long);
+extern struct inode *ext4_iget_normal(struct super_block *, unsigned long);
+extern int  ext4_write_inode(struct inode *, struct writeback_control *);
+extern int  ext4_setattr(struct dentry *, struct iattr *);
+extern int  ext4_getattr(struct vfsmount *mnt, struct dentry *dentry,
+                               struct kstat *stat);
+extern void ext4_evict_inode(struct inode *);
+extern void ext4_clear_inode(struct inode *);
+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_inode_attach_jinode(struct inode *inode);
+extern int ext4_can_truncate(struct inode *inode);
+extern void ext4_truncate(struct inode *);
+extern int ext4_punch_hole(struct inode *inode, loff_t offset, loff_t length);
+extern int ext4_truncate_restart_trans(handle_t *, struct inode *, int nblocks);
+extern void ext4_set_inode_flags(struct inode *);
+extern void ext4_get_inode_flags(struct ext4_inode_info *);
+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 int ext4_page_mkwrite(struct vm_area_struct *vma, struct vm_fault *vmf);
+extern qsize_t *ext4_get_reserved_space(struct inode *inode);
+extern void ext4_da_update_reserve_space(struct inode *inode,
+                                       int used, int quota_claim);
+
+/* indirect.c */
+extern int ext4_ind_map_blocks(handle_t *handle, struct inode *inode,
+                               struct ext4_map_blocks *map, int flags);
+extern ssize_t ext4_ind_direct_IO(struct kiocb *iocb, struct iov_iter *iter,
+                                 loff_t offset);
+extern int ext4_ind_calc_metadata_amount(struct inode *inode, sector_t lblock);
+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);
+
+/* migrate.c */
+extern int ext4_ext_migrate(struct inode *);
+extern int ext4_ind_migrate(struct inode *inode);
+
+/* namei.c */
+extern int ext4_dirent_csum_verify(struct inode *inode,
+                                  struct ext4_dir_entry *dirent);
+extern int ext4_orphan_add(handle_t *, struct inode *);
+extern int ext4_orphan_del(handle_t *, struct inode *);
+extern int ext4_htree_fill_tree(struct file *dir_file, __u32 start_hash,
+                               __u32 start_minor_hash, __u32 *next_hash);
+extern int search_dir(struct buffer_head *bh,
+                     char *search_buf,
+                     int buf_size,
+                     struct inode *dir,
+                     const struct qstr *d_name,
+                     unsigned int offset,
+                     struct ext4_dir_entry_2 **res_dir);
+extern int ext4_generic_delete_entry(handle_t *handle,
+                                    struct inode *dir,
+                                    struct ext4_dir_entry_2 *de_del,
+                                    struct buffer_head *bh,
+                                    void *entry_buf,
+                                    int buf_size,
+                                    int csum_size);
+extern int ext4_empty_dir(struct inode *inode);
+
+/* resize.c */
+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);
+
+/* super.c */
+extern int ext4_calculate_overhead(struct super_block *sb);
+extern void ext4_superblock_csum_set(struct super_block *sb);
+extern void *ext4_kvmalloc(size_t size, gfp_t flags);
+extern void *ext4_kvzalloc(size_t size, gfp_t flags);
+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 __printf(4, 5)
+void __ext4_error(struct super_block *, const char *, unsigned int,
+                 const char *, ...);
+extern __printf(5, 6)
+void __ext4_error_inode(struct inode *, const char *, unsigned int, ext4_fsblk_t,
+                     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_abort(struct super_block *, const char *, unsigned int,
+                 const char *, ...);
+extern __printf(4, 5)
+void __ext4_warning(struct super_block *, const char *, unsigned int,
+                   const char *, ...);
+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 *, ...);
+
+#ifdef CONFIG_PRINTK
+
+#define ext4_error_inode(inode, func, line, block, fmt, ...)           \
+       __ext4_error_inode(inode, func, line, block, 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__, fmt, ##__VA_ARGS__)
+#define ext4_abort(sb, fmt, ...)                                       \
+       __ext4_abort(sb, __func__, __LINE__, fmt, ##__VA_ARGS__)
+#define ext4_warning(sb, fmt, ...)                                     \
+       __ext4_warning(sb, __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, " ");                   \
+} 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, " ");                                   \
+} while (0)
+#define ext4_abort(sb, fmt, ...)                                       \
+do {                                                                   \
+       no_printk(fmt, ##__VA_ARGS__);                                  \
+       __ext4_abort(sb, "", 0, " ");                                   \
+} while (0)
+#define ext4_warning(sb, fmt, ...)                                     \
+do {                                                                   \
+       no_printk(fmt, ##__VA_ARGS__);                                  \
+       __ext4_warning(sb, "", 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 void ext4_update_dynamic_rev(struct super_block *sb);
+extern int ext4_update_compat_feature(handle_t *handle, struct super_block *sb,
+                                       __u32 compat);
+extern int ext4_update_rocompat_feature(handle_t *handle,
+                                       struct super_block *sb, __u32 rocompat);
+extern int ext4_update_incompat_feature(handle_t *handle,
+                                       struct super_block *sb, __u32 incompat);
+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_group_desc_csum(struct super_block *sb)
+{
+       return EXT4_HAS_RO_COMPAT_FEATURE(sb,
+                                         EXT4_FEATURE_RO_COMPAT_GDT_CSUM) ||
+              (EXT4_SB(sb)->s_chksum_driver != NULL);
+}
+
+static inline int ext4_has_metadata_csum(struct super_block *sb)
+{
+       WARN_ON_ONCE(EXT4_HAS_RO_COMPAT_FEATURE(sb,
+                       EXT4_FEATURE_RO_COMPAT_METADATA_CSUM) &&
+                    !EXT4_SB(sb)->s_chksum_driver);
+
+       return (EXT4_SB(sb)->s_chksum_driver != NULL);
+}
+static inline ext4_fsblk_t ext4_blocks_count(struct ext4_super_block *es)
+{
+       return ((ext4_fsblk_t)le32_to_cpu(es->s_blocks_count_hi) << 32) |
+               le32_to_cpu(es->s_blocks_count_lo);
+}
+
+static inline ext4_fsblk_t ext4_r_blocks_count(struct ext4_super_block *es)
+{
+       return ((ext4_fsblk_t)le32_to_cpu(es->s_r_blocks_count_hi) << 32) |
+               le32_to_cpu(es->s_r_blocks_count_lo);
+}
+
+static inline ext4_fsblk_t ext4_free_blocks_count(struct ext4_super_block *es)
+{
+       return ((ext4_fsblk_t)le32_to_cpu(es->s_free_blocks_count_hi) << 32) |
+               le32_to_cpu(es->s_free_blocks_count_lo);
+}
+
+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 ext4_inode *raw_inode)
+{
+       if (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);
+       else
+               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);
+        grp_info = EXT4_SB(sb)->s_group_info;
+        indexv = group >> (EXT4_DESC_PER_BLOCK_BITS(sb));
+        indexh = group & ((EXT4_DESC_PER_BLOCK(sb)) - 1);
+        return grp_info[indexv][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_mutex 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) &&
+                    !mutex_is_locked(&inode->i_mutex));
+       down_write(&EXT4_I(inode)->i_data_sem);
+       if (newsize > EXT4_I(inode)->i_disksize)
+               EXT4_I(inode)->i_disksize = newsize;
+       up_write(&EXT4_I(inode)->i_data_sem);
+}
+
+/* Update i_size, i_disksize. Requires i_mutex 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;
+}
+
+struct ext4_group_info {
+       unsigned long   bb_state;
+       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 */
+       ext4_grpblk_t   bb_largest_free_order;/* order of largest frag in BG */
+       struct          list_head bb_prealloc_list;
+#ifdef DOUBLE_CHECK
+       void            *bb_bitmap;
+#endif
+       struct rw_semaphore alloc_sem;
+       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_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_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));
+}
+
+/*
+ * 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,
+                                        unsigned flags,
+                                        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,
+                                          unsigned flags,
+                                          struct page **pagep,
+                                          void **fsdata);
+extern int ext4_da_write_inline_data_end(struct inode *inode, loff_t pos,
+                                        unsigned len, unsigned copied,
+                                        struct page *page);
+extern int ext4_try_add_inline_entry(handle_t *handle, struct dentry *dentry,
+                                    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 htree_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,
+                                       const struct qstr *d_name,
+                                       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 int 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 int ext4_try_to_evict_inline_data(handle_t *handle,
+                                        struct inode *inode,
+                                        int needed);
+extern void 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 initialize_dirent_tail(struct ext4_dir_entry_tail *t,
+                                  unsigned int blocksize);
+extern int ext4_handle_dirty_dirent_node(handle_t *handle,
+                                        struct inode *inode,
+                                        struct buffer_head *bh);
+#define S_SHIFT 12
+static unsigned char ext4_type_by_mode[S_IFMT >> S_SHIFT] = {
+       [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_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_FILETYPE))
+               de->file_type = ext4_type_by_mode[(mode & S_IFMT)>>S_SHIFT];
+}
+
+/* readpages.c */
+extern int ext4_mpage_readpages(struct address_space *mapping,
+                               struct list_head *pages, struct page *page,
+                               unsigned nr_pages);
+
+/* symlink.c */
+extern const struct inode_operations ext4_symlink_inode_operations;
+extern const struct inode_operations ext4_fast_symlink_inode_operations;
+
+/* 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_data_block_valid(struct ext4_sb_info *sbi,
+                                ext4_fsblk_t start_blk,
+                                unsigned int count);
+extern int ext4_check_blockref(const char *, unsigned int,
+                              struct inode *, __le32 *, unsigned int);
+
+/* 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 int ext4_ext_tree_init(handle_t *handle, struct inode *);
+extern int ext4_ext_writepage_trans_blocks(struct inode *, int);
+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 void 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_map_blocks(handle_t *handle, struct inode *inode,
+                          struct ext4_map_blocks *map, int flags);
+extern int ext4_ext_calc_metadata_amount(struct inode *inode,
+                                        ext4_lblk_t lblocks);
+extern int ext4_ext_calc_credits_for_single_extent(struct inode *inode,
+                                                  int num,
+                                                  struct ext4_ext_path *path);
+extern int ext4_can_extents_be_merged(struct inode *inode,
+                                     struct ext4_extent *ex1,
+                                     struct ext4_extent *ex2);
+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 int ext4_find_delalloc_range(struct inode *inode,
+                                   ext4_lblk_t lblk_start,
+                                   ext4_lblk_t lblk_end);
+extern int ext4_find_delalloc_cluster(struct inode *inode, ext4_lblk_t lblk);
+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_ext_precache(struct inode *inode);
+extern int ext4_collapse_range(struct inode *inode, loff_t offset, loff_t len);
+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);
+
+/* 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,
+                              struct writeback_control *wbc,
+                              bool keep_towrite);
+
+/* mmp.c */
+extern int ext4_multi_mount_protect(struct super_block *, ext4_fsblk_t);
+
+/*
+ * 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);
+}
+
+/*
+ * Disable DIO read nolock optimization, so new dioreaders will be forced
+ * to grab i_mutex
+ */
+static inline void ext4_inode_block_unlocked_dio(struct inode *inode)
+{
+       ext4_set_inode_state(inode, EXT4_STATE_DIOREAD_LOCK);
+       smp_mb();
+}
+static inline void ext4_inode_resume_unlocked_dio(struct inode *inode)
+{
+       smp_mb();
+       ext4_clear_inode_state(inode, EXT4_STATE_DIOREAD_LOCK);
+}
+
+#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])
+#define ext4_aio_mutex(v)  (&ext4__aio_mutex[((unsigned long)(v)) %\
+                                            EXT4_WQ_HASH_SZ])
+extern wait_queue_head_t ext4__ioend_wq[EXT4_WQ_HASH_SZ];
+extern struct mutex ext4__aio_mutex[EXT4_WQ_HASH_SZ];
+
+#define EXT4_RESIZING  0
+extern int ext4_resize_begin(struct super_block *sb);
+extern void ext4_resize_end(struct super_block *sb);
+
+#endif /* __KERNEL__ */
+
+#endif /* _EXT4_H */