linux/fs/ext4/ext4.h
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   1/*
   2 *  ext4.h
   3 *
   4 * Copyright (C) 1992, 1993, 1994, 1995
   5 * Remy Card (card@masi.ibp.fr)
   6 * Laboratoire MASI - Institut Blaise Pascal
   7 * Universite Pierre et Marie Curie (Paris VI)
   8 *
   9 *  from
  10 *
  11 *  linux/include/linux/minix_fs.h
  12 *
  13 *  Copyright (C) 1991, 1992  Linus Torvalds
  14 */
  15
  16#ifndef _EXT4_H
  17#define _EXT4_H
  18
  19#include <linux/types.h>
  20#include <linux/blkdev.h>
  21#include <linux/magic.h>
  22#include <linux/jbd2.h>
  23#include <linux/quota.h>
  24#include <linux/rwsem.h>
  25#include <linux/rbtree.h>
  26#include <linux/seqlock.h>
  27#include <linux/mutex.h>
  28#include <linux/timer.h>
  29#include <linux/wait.h>
  30#include <linux/blockgroup_lock.h>
  31#include <linux/percpu_counter.h>
  32#include <crypto/hash.h>
  33#ifdef __KERNEL__
  34#include <linux/compat.h>
  35#endif
  36
  37/*
  38 * The fourth extended filesystem constants/structures
  39 */
  40
  41/*
  42 * Define EXT4FS_DEBUG to produce debug messages
  43 */
  44#undef EXT4FS_DEBUG
  45
  46/*
  47 * Debug code
  48 */
  49#ifdef EXT4FS_DEBUG
  50#define ext4_debug(f, a...)                                             \
  51        do {                                                            \
  52                printk(KERN_DEBUG "EXT4-fs DEBUG (%s, %d): %s:",        \
  53                        __FILE__, __LINE__, __func__);                  \
  54                printk(KERN_DEBUG f, ## a);                             \
  55        } while (0)
  56#else
  57#define ext4_debug(fmt, ...)    no_printk(fmt, ##__VA_ARGS__)
  58#endif
  59
  60#define EXT4_ERROR_INODE(inode, fmt, a...) \
  61        ext4_error_inode((inode), __func__, __LINE__, 0, (fmt), ## a)
  62
  63#define EXT4_ERROR_INODE_BLOCK(inode, block, fmt, a...)                 \
  64        ext4_error_inode((inode), __func__, __LINE__, (block), (fmt), ## a)
  65
  66#define EXT4_ERROR_FILE(file, block, fmt, a...)                         \
  67        ext4_error_file((file), __func__, __LINE__, (block), (fmt), ## a)
  68
  69/* data type for block offset of block group */
  70typedef int ext4_grpblk_t;
  71
  72/* data type for filesystem-wide blocks number */
  73typedef unsigned long long ext4_fsblk_t;
  74
  75/* data type for file logical block number */
  76typedef __u32 ext4_lblk_t;
  77
  78/* data type for block group number */
  79typedef unsigned int ext4_group_t;
  80
  81/*
  82 * Flags used in mballoc's allocation_context flags field.
  83 *
  84 * Also used to show what's going on for debugging purposes when the
  85 * flag field is exported via the traceport interface
  86 */
  87
  88/* prefer goal again. length */
  89#define EXT4_MB_HINT_MERGE              0x0001
  90/* blocks already reserved */
  91#define EXT4_MB_HINT_RESERVED           0x0002
  92/* metadata is being allocated */
  93#define EXT4_MB_HINT_METADATA           0x0004
  94/* first blocks in the file */
  95#define EXT4_MB_HINT_FIRST              0x0008
  96/* search for the best chunk */
  97#define EXT4_MB_HINT_BEST               0x0010
  98/* data is being allocated */
  99#define EXT4_MB_HINT_DATA               0x0020
 100/* don't preallocate (for tails) */
 101#define EXT4_MB_HINT_NOPREALLOC         0x0040
 102/* allocate for locality group */
 103#define EXT4_MB_HINT_GROUP_ALLOC        0x0080
 104/* allocate goal blocks or none */
 105#define EXT4_MB_HINT_GOAL_ONLY          0x0100
 106/* goal is meaningful */
 107#define EXT4_MB_HINT_TRY_GOAL           0x0200
 108/* blocks already pre-reserved by delayed allocation */
 109#define EXT4_MB_DELALLOC_RESERVED       0x0400
 110/* We are doing stream allocation */
 111#define EXT4_MB_STREAM_ALLOC            0x0800
 112/* Use reserved root blocks if needed */
 113#define EXT4_MB_USE_ROOT_BLOCKS         0x1000
 114
 115struct ext4_allocation_request {
 116        /* target inode for block we're allocating */
 117        struct inode *inode;
 118        /* how many blocks we want to allocate */
 119        unsigned int len;
 120        /* logical block in target inode */
 121        ext4_lblk_t logical;
 122        /* the closest logical allocated block to the left */
 123        ext4_lblk_t lleft;
 124        /* the closest logical allocated block to the right */
 125        ext4_lblk_t lright;
 126        /* phys. target (a hint) */
 127        ext4_fsblk_t goal;
 128        /* phys. block for the closest logical allocated block to the left */
 129        ext4_fsblk_t pleft;
 130        /* phys. block for the closest logical allocated block to the right */
 131        ext4_fsblk_t pright;
 132        /* flags. see above EXT4_MB_HINT_* */
 133        unsigned int flags;
 134};
 135
 136/*
 137 * Logical to physical block mapping, used by ext4_map_blocks()
 138 *
 139 * This structure is used to pass requests into ext4_map_blocks() as
 140 * well as to store the information returned by ext4_map_blocks().  It
 141 * takes less room on the stack than a struct buffer_head.
 142 */
 143#define EXT4_MAP_NEW            (1 << BH_New)
 144#define EXT4_MAP_MAPPED         (1 << BH_Mapped)
 145#define EXT4_MAP_UNWRITTEN      (1 << BH_Unwritten)
 146#define EXT4_MAP_BOUNDARY       (1 << BH_Boundary)
 147#define EXT4_MAP_UNINIT         (1 << BH_Uninit)
 148/* Sometimes (in the bigalloc case, from ext4_da_get_block_prep) the caller of
 149 * ext4_map_blocks wants to know whether or not the underlying cluster has
 150 * already been accounted for. EXT4_MAP_FROM_CLUSTER conveys to the caller that
 151 * the requested mapping was from previously mapped (or delayed allocated)
 152 * cluster. We use BH_AllocFromCluster only for this flag. BH_AllocFromCluster
 153 * should never appear on buffer_head's state flags.
 154 */
 155#define EXT4_MAP_FROM_CLUSTER   (1 << BH_AllocFromCluster)
 156#define EXT4_MAP_FLAGS          (EXT4_MAP_NEW | EXT4_MAP_MAPPED |\
 157                                 EXT4_MAP_UNWRITTEN | EXT4_MAP_BOUNDARY |\
 158                                 EXT4_MAP_UNINIT | EXT4_MAP_FROM_CLUSTER)
 159
 160struct ext4_map_blocks {
 161        ext4_fsblk_t m_pblk;
 162        ext4_lblk_t m_lblk;
 163        unsigned int m_len;
 164        unsigned int m_flags;
 165};
 166
 167/*
 168 * For delayed allocation tracking
 169 */
 170struct mpage_da_data {
 171        struct inode *inode;
 172        sector_t b_blocknr;             /* start block number of extent */
 173        size_t b_size;                  /* size of extent */
 174        unsigned long b_state;          /* state of the extent */
 175        unsigned long first_page, next_page;    /* extent of pages */
 176        struct writeback_control *wbc;
 177        int io_done;
 178        int pages_written;
 179        int retval;
 180};
 181
 182/*
 183 * Flags for ext4_io_end->flags
 184 */
 185#define EXT4_IO_END_UNWRITTEN   0x0001
 186#define EXT4_IO_END_ERROR       0x0002
 187#define EXT4_IO_END_QUEUED      0x0004
 188#define EXT4_IO_END_DIRECT      0x0008
 189
 190struct ext4_io_page {
 191        struct page     *p_page;
 192        atomic_t        p_count;
 193};
 194
 195#define MAX_IO_PAGES 128
 196
 197/*
 198 * For converting uninitialized extents on a work queue.
 199 *
 200 * 'page' is only used from the writepage() path; 'pages' is only used for
 201 * buffered writes; they are used to keep page references until conversion
 202 * takes place.  For AIO/DIO, neither field is filled in.
 203 */
 204typedef struct ext4_io_end {
 205        struct list_head        list;           /* per-file finished IO list */
 206        struct inode            *inode;         /* file being written to */
 207        unsigned int            flag;           /* unwritten or not */
 208        struct page             *page;          /* for writepage() path */
 209        loff_t                  offset;         /* offset in the file */
 210        ssize_t                 size;           /* size of the extent */
 211        struct work_struct      work;           /* data work queue */
 212        struct kiocb            *iocb;          /* iocb struct for AIO */
 213        int                     result;         /* error value for AIO */
 214        int                     num_io_pages;   /* for writepages() */
 215        struct ext4_io_page     *pages[MAX_IO_PAGES]; /* for writepages() */
 216} ext4_io_end_t;
 217
 218struct ext4_io_submit {
 219        int                     io_op;
 220        struct bio              *io_bio;
 221        ext4_io_end_t           *io_end;
 222        struct ext4_io_page     *io_page;
 223        sector_t                io_next_block;
 224};
 225
 226/*
 227 * Special inodes numbers
 228 */
 229#define EXT4_BAD_INO             1      /* Bad blocks inode */
 230#define EXT4_ROOT_INO            2      /* Root inode */
 231#define EXT4_USR_QUOTA_INO       3      /* User quota inode */
 232#define EXT4_GRP_QUOTA_INO       4      /* Group quota inode */
 233#define EXT4_BOOT_LOADER_INO     5      /* Boot loader inode */
 234#define EXT4_UNDEL_DIR_INO       6      /* Undelete directory inode */
 235#define EXT4_RESIZE_INO          7      /* Reserved group descriptors inode */
 236#define EXT4_JOURNAL_INO         8      /* Journal inode */
 237
 238/* First non-reserved inode for old ext4 filesystems */
 239#define EXT4_GOOD_OLD_FIRST_INO 11
 240
 241/*
 242 * Maximal count of links to a file
 243 */
 244#define EXT4_LINK_MAX           65000
 245
 246/*
 247 * Macro-instructions used to manage several block sizes
 248 */
 249#define EXT4_MIN_BLOCK_SIZE             1024
 250#define EXT4_MAX_BLOCK_SIZE             65536
 251#define EXT4_MIN_BLOCK_LOG_SIZE         10
 252#define EXT4_MAX_BLOCK_LOG_SIZE         16
 253#ifdef __KERNEL__
 254# define EXT4_BLOCK_SIZE(s)             ((s)->s_blocksize)
 255#else
 256# define EXT4_BLOCK_SIZE(s)             (EXT4_MIN_BLOCK_SIZE << (s)->s_log_block_size)
 257#endif
 258#define EXT4_ADDR_PER_BLOCK(s)          (EXT4_BLOCK_SIZE(s) / sizeof(__u32))
 259#define EXT4_CLUSTER_SIZE(s)            (EXT4_BLOCK_SIZE(s) << \
 260                                         EXT4_SB(s)->s_cluster_bits)
 261#ifdef __KERNEL__
 262# define EXT4_BLOCK_SIZE_BITS(s)        ((s)->s_blocksize_bits)
 263# define EXT4_CLUSTER_BITS(s)           (EXT4_SB(s)->s_cluster_bits)
 264#else
 265# define EXT4_BLOCK_SIZE_BITS(s)        ((s)->s_log_block_size + 10)
 266#endif
 267#ifdef __KERNEL__
 268#define EXT4_ADDR_PER_BLOCK_BITS(s)     (EXT4_SB(s)->s_addr_per_block_bits)
 269#define EXT4_INODE_SIZE(s)              (EXT4_SB(s)->s_inode_size)
 270#define EXT4_FIRST_INO(s)               (EXT4_SB(s)->s_first_ino)
 271#else
 272#define EXT4_INODE_SIZE(s)      (((s)->s_rev_level == EXT4_GOOD_OLD_REV) ? \
 273                                 EXT4_GOOD_OLD_INODE_SIZE : \
 274                                 (s)->s_inode_size)
 275#define EXT4_FIRST_INO(s)       (((s)->s_rev_level == EXT4_GOOD_OLD_REV) ? \
 276                                 EXT4_GOOD_OLD_FIRST_INO : \
 277                                 (s)->s_first_ino)
 278#endif
 279#define EXT4_BLOCK_ALIGN(size, blkbits)         ALIGN((size), (1 << (blkbits)))
 280
 281/* Translate a block number to a cluster number */
 282#define EXT4_B2C(sbi, blk)      ((blk) >> (sbi)->s_cluster_bits)
 283/* Translate a cluster number to a block number */
 284#define EXT4_C2B(sbi, cluster)  ((cluster) << (sbi)->s_cluster_bits)
 285/* Translate # of blks to # of clusters */
 286#define EXT4_NUM_B2C(sbi, blks) (((blks) + (sbi)->s_cluster_ratio - 1) >> \
 287                                 (sbi)->s_cluster_bits)
 288
 289/*
 290 * Structure of a blocks group descriptor
 291 */
 292struct ext4_group_desc
 293{
 294        __le32  bg_block_bitmap_lo;     /* Blocks bitmap block */
 295        __le32  bg_inode_bitmap_lo;     /* Inodes bitmap block */
 296        __le32  bg_inode_table_lo;      /* Inodes table block */
 297        __le16  bg_free_blocks_count_lo;/* Free blocks count */
 298        __le16  bg_free_inodes_count_lo;/* Free inodes count */
 299        __le16  bg_used_dirs_count_lo;  /* Directories count */
 300        __le16  bg_flags;               /* EXT4_BG_flags (INODE_UNINIT, etc) */
 301        __le32  bg_exclude_bitmap_lo;   /* Exclude bitmap for snapshots */
 302        __le16  bg_block_bitmap_csum_lo;/* crc32c(s_uuid+grp_num+bbitmap) LE */
 303        __le16  bg_inode_bitmap_csum_lo;/* crc32c(s_uuid+grp_num+ibitmap) LE */
 304        __le16  bg_itable_unused_lo;    /* Unused inodes count */
 305        __le16  bg_checksum;            /* crc16(sb_uuid+group+desc) */
 306        __le32  bg_block_bitmap_hi;     /* Blocks bitmap block MSB */
 307        __le32  bg_inode_bitmap_hi;     /* Inodes bitmap block MSB */
 308        __le32  bg_inode_table_hi;      /* Inodes table block MSB */
 309        __le16  bg_free_blocks_count_hi;/* Free blocks count MSB */
 310        __le16  bg_free_inodes_count_hi;/* Free inodes count MSB */
 311        __le16  bg_used_dirs_count_hi;  /* Directories count MSB */
 312        __le16  bg_itable_unused_hi;    /* Unused inodes count MSB */
 313        __le32  bg_exclude_bitmap_hi;   /* Exclude bitmap block MSB */
 314        __le16  bg_block_bitmap_csum_hi;/* crc32c(s_uuid+grp_num+bbitmap) BE */
 315        __le16  bg_inode_bitmap_csum_hi;/* crc32c(s_uuid+grp_num+ibitmap) BE */
 316        __u32   bg_reserved;
 317};
 318
 319#define EXT4_BG_INODE_BITMAP_CSUM_HI_END        \
 320        (offsetof(struct ext4_group_desc, bg_inode_bitmap_csum_hi) + \
 321         sizeof(__le16))
 322#define EXT4_BG_BLOCK_BITMAP_CSUM_HI_END        \
 323        (offsetof(struct ext4_group_desc, bg_block_bitmap_csum_hi) + \
 324         sizeof(__le16))
 325
 326/*
 327 * Structure of a flex block group info
 328 */
 329
 330struct flex_groups {
 331        atomic_t free_inodes;
 332        atomic_t free_clusters;
 333        atomic_t used_dirs;
 334};
 335
 336#define EXT4_BG_INODE_UNINIT    0x0001 /* Inode table/bitmap not in use */
 337#define EXT4_BG_BLOCK_UNINIT    0x0002 /* Block bitmap not in use */
 338#define EXT4_BG_INODE_ZEROED    0x0004 /* On-disk itable initialized to zero */
 339
 340/*
 341 * Macro-instructions used to manage group descriptors
 342 */
 343#define EXT4_MIN_DESC_SIZE              32
 344#define EXT4_MIN_DESC_SIZE_64BIT        64
 345#define EXT4_MAX_DESC_SIZE              EXT4_MIN_BLOCK_SIZE
 346#define EXT4_DESC_SIZE(s)               (EXT4_SB(s)->s_desc_size)
 347#ifdef __KERNEL__
 348# define EXT4_BLOCKS_PER_GROUP(s)       (EXT4_SB(s)->s_blocks_per_group)
 349# define EXT4_CLUSTERS_PER_GROUP(s)     (EXT4_SB(s)->s_clusters_per_group)
 350# define EXT4_DESC_PER_BLOCK(s)         (EXT4_SB(s)->s_desc_per_block)
 351# define EXT4_INODES_PER_GROUP(s)       (EXT4_SB(s)->s_inodes_per_group)
 352# define EXT4_DESC_PER_BLOCK_BITS(s)    (EXT4_SB(s)->s_desc_per_block_bits)
 353#else
 354# define EXT4_BLOCKS_PER_GROUP(s)       ((s)->s_blocks_per_group)
 355# define EXT4_DESC_PER_BLOCK(s)         (EXT4_BLOCK_SIZE(s) / EXT4_DESC_SIZE(s))
 356# define EXT4_INODES_PER_GROUP(s)       ((s)->s_inodes_per_group)
 357#endif
 358
 359/*
 360 * Constants relative to the data blocks
 361 */
 362#define EXT4_NDIR_BLOCKS                12
 363#define EXT4_IND_BLOCK                  EXT4_NDIR_BLOCKS
 364#define EXT4_DIND_BLOCK                 (EXT4_IND_BLOCK + 1)
 365#define EXT4_TIND_BLOCK                 (EXT4_DIND_BLOCK + 1)
 366#define EXT4_N_BLOCKS                   (EXT4_TIND_BLOCK + 1)
 367
 368/*
 369 * Inode flags
 370 */
 371#define EXT4_SECRM_FL                   0x00000001 /* Secure deletion */
 372#define EXT4_UNRM_FL                    0x00000002 /* Undelete */
 373#define EXT4_COMPR_FL                   0x00000004 /* Compress file */
 374#define EXT4_SYNC_FL                    0x00000008 /* Synchronous updates */
 375#define EXT4_IMMUTABLE_FL               0x00000010 /* Immutable file */
 376#define EXT4_APPEND_FL                  0x00000020 /* writes to file may only append */
 377#define EXT4_NODUMP_FL                  0x00000040 /* do not dump file */
 378#define EXT4_NOATIME_FL                 0x00000080 /* do not update atime */
 379/* Reserved for compression usage... */
 380#define EXT4_DIRTY_FL                   0x00000100
 381#define EXT4_COMPRBLK_FL                0x00000200 /* One or more compressed clusters */
 382#define EXT4_NOCOMPR_FL                 0x00000400 /* Don't compress */
 383#define EXT4_ECOMPR_FL                  0x00000800 /* Compression error */
 384/* End compression flags --- maybe not all used */
 385#define EXT4_INDEX_FL                   0x00001000 /* hash-indexed directory */
 386#define EXT4_IMAGIC_FL                  0x00002000 /* AFS directory */
 387#define EXT4_JOURNAL_DATA_FL            0x00004000 /* file data should be journaled */
 388#define EXT4_NOTAIL_FL                  0x00008000 /* file tail should not be merged */
 389#define EXT4_DIRSYNC_FL                 0x00010000 /* dirsync behaviour (directories only) */
 390#define EXT4_TOPDIR_FL                  0x00020000 /* Top of directory hierarchies*/
 391#define EXT4_HUGE_FILE_FL               0x00040000 /* Set to each huge file */
 392#define EXT4_EXTENTS_FL                 0x00080000 /* Inode uses extents */
 393#define EXT4_EA_INODE_FL                0x00200000 /* Inode used for large EA */
 394#define EXT4_EOFBLOCKS_FL               0x00400000 /* Blocks allocated beyond EOF */
 395#define EXT4_RESERVED_FL                0x80000000 /* reserved for ext4 lib */
 396
 397#define EXT4_FL_USER_VISIBLE            0x004BDFFF /* User visible flags */
 398#define EXT4_FL_USER_MODIFIABLE         0x004B80FF /* User modifiable flags */
 399
 400/* Flags that should be inherited by new inodes from their parent. */
 401#define EXT4_FL_INHERITED (EXT4_SECRM_FL | EXT4_UNRM_FL | EXT4_COMPR_FL |\
 402                           EXT4_SYNC_FL | EXT4_NODUMP_FL | EXT4_NOATIME_FL |\
 403                           EXT4_NOCOMPR_FL | EXT4_JOURNAL_DATA_FL |\
 404                           EXT4_NOTAIL_FL | EXT4_DIRSYNC_FL)
 405
 406/* Flags that are appropriate for regular files (all but dir-specific ones). */
 407#define EXT4_REG_FLMASK (~(EXT4_DIRSYNC_FL | EXT4_TOPDIR_FL))
 408
 409/* Flags that are appropriate for non-directories/regular files. */
 410#define EXT4_OTHER_FLMASK (EXT4_NODUMP_FL | EXT4_NOATIME_FL)
 411
 412/* Mask out flags that are inappropriate for the given type of inode. */
 413static inline __u32 ext4_mask_flags(umode_t mode, __u32 flags)
 414{
 415        if (S_ISDIR(mode))
 416                return flags;
 417        else if (S_ISREG(mode))
 418                return flags & EXT4_REG_FLMASK;
 419        else
 420                return flags & EXT4_OTHER_FLMASK;
 421}
 422
 423/*
 424 * Inode flags used for atomic set/get
 425 */
 426enum {
 427        EXT4_INODE_SECRM        = 0,    /* Secure deletion */
 428        EXT4_INODE_UNRM         = 1,    /* Undelete */
 429        EXT4_INODE_COMPR        = 2,    /* Compress file */
 430        EXT4_INODE_SYNC         = 3,    /* Synchronous updates */
 431        EXT4_INODE_IMMUTABLE    = 4,    /* Immutable file */
 432        EXT4_INODE_APPEND       = 5,    /* writes to file may only append */
 433        EXT4_INODE_NODUMP       = 6,    /* do not dump file */
 434        EXT4_INODE_NOATIME      = 7,    /* do not update atime */
 435/* Reserved for compression usage... */
 436        EXT4_INODE_DIRTY        = 8,
 437        EXT4_INODE_COMPRBLK     = 9,    /* One or more compressed clusters */
 438        EXT4_INODE_NOCOMPR      = 10,   /* Don't compress */
 439        EXT4_INODE_ECOMPR       = 11,   /* Compression error */
 440/* End compression flags --- maybe not all used */
 441        EXT4_INODE_INDEX        = 12,   /* hash-indexed directory */
 442        EXT4_INODE_IMAGIC       = 13,   /* AFS directory */
 443        EXT4_INODE_JOURNAL_DATA = 14,   /* file data should be journaled */
 444        EXT4_INODE_NOTAIL       = 15,   /* file tail should not be merged */
 445        EXT4_INODE_DIRSYNC      = 16,   /* dirsync behaviour (directories only) */
 446        EXT4_INODE_TOPDIR       = 17,   /* Top of directory hierarchies*/
 447        EXT4_INODE_HUGE_FILE    = 18,   /* Set to each huge file */
 448        EXT4_INODE_EXTENTS      = 19,   /* Inode uses extents */
 449        EXT4_INODE_EA_INODE     = 21,   /* Inode used for large EA */
 450        EXT4_INODE_EOFBLOCKS    = 22,   /* Blocks allocated beyond EOF */
 451        EXT4_INODE_RESERVED     = 31,   /* reserved for ext4 lib */
 452};
 453
 454#define TEST_FLAG_VALUE(FLAG) (EXT4_##FLAG##_FL == (1 << EXT4_INODE_##FLAG))
 455#define CHECK_FLAG_VALUE(FLAG) if (!TEST_FLAG_VALUE(FLAG)) { \
 456        printk(KERN_EMERG "EXT4 flag fail: " #FLAG ": %d %d\n", \
 457                EXT4_##FLAG##_FL, EXT4_INODE_##FLAG); BUG_ON(1); }
 458
 459/*
 460 * Since it's pretty easy to mix up bit numbers and hex values, and we
 461 * can't do a compile-time test for ENUM values, we use a run-time
 462 * test to make sure that EXT4_XXX_FL is consistent with respect to
 463 * EXT4_INODE_XXX.  If all is well the printk and BUG_ON will all drop
 464 * out so it won't cost any extra space in the compiled kernel image.
 465 * But it's important that these values are the same, since we are
 466 * using EXT4_INODE_XXX to test for the flag values, but EXT4_XX_FL
 467 * must be consistent with the values of FS_XXX_FL defined in
 468 * include/linux/fs.h and the on-disk values found in ext2, ext3, and
 469 * ext4 filesystems, and of course the values defined in e2fsprogs.
 470 *
 471 * It's not paranoia if the Murphy's Law really *is* out to get you.  :-)
 472 */
 473static inline void ext4_check_flag_values(void)
 474{
 475        CHECK_FLAG_VALUE(SECRM);
 476        CHECK_FLAG_VALUE(UNRM);
 477        CHECK_FLAG_VALUE(COMPR);
 478        CHECK_FLAG_VALUE(SYNC);
 479        CHECK_FLAG_VALUE(IMMUTABLE);
 480        CHECK_FLAG_VALUE(APPEND);
 481        CHECK_FLAG_VALUE(NODUMP);
 482        CHECK_FLAG_VALUE(NOATIME);
 483        CHECK_FLAG_VALUE(DIRTY);
 484        CHECK_FLAG_VALUE(COMPRBLK);
 485        CHECK_FLAG_VALUE(NOCOMPR);
 486        CHECK_FLAG_VALUE(ECOMPR);
 487        CHECK_FLAG_VALUE(INDEX);
 488        CHECK_FLAG_VALUE(IMAGIC);
 489        CHECK_FLAG_VALUE(JOURNAL_DATA);
 490        CHECK_FLAG_VALUE(NOTAIL);
 491        CHECK_FLAG_VALUE(DIRSYNC);
 492        CHECK_FLAG_VALUE(TOPDIR);
 493        CHECK_FLAG_VALUE(HUGE_FILE);
 494        CHECK_FLAG_VALUE(EXTENTS);
 495        CHECK_FLAG_VALUE(EA_INODE);
 496        CHECK_FLAG_VALUE(EOFBLOCKS);
 497        CHECK_FLAG_VALUE(RESERVED);
 498}
 499
 500/* Used to pass group descriptor data when online resize is done */
 501struct ext4_new_group_input {
 502        __u32 group;            /* Group number for this data */
 503        __u64 block_bitmap;     /* Absolute block number of block bitmap */
 504        __u64 inode_bitmap;     /* Absolute block number of inode bitmap */
 505        __u64 inode_table;      /* Absolute block number of inode table start */
 506        __u32 blocks_count;     /* Total number of blocks in this group */
 507        __u16 reserved_blocks;  /* Number of reserved blocks in this group */
 508        __u16 unused;
 509};
 510
 511#if defined(__KERNEL__) && defined(CONFIG_COMPAT)
 512struct compat_ext4_new_group_input {
 513        u32 group;
 514        compat_u64 block_bitmap;
 515        compat_u64 inode_bitmap;
 516        compat_u64 inode_table;
 517        u32 blocks_count;
 518        u16 reserved_blocks;
 519        u16 unused;
 520};
 521#endif
 522
 523/* The struct ext4_new_group_input in kernel space, with free_blocks_count */
 524struct ext4_new_group_data {
 525        __u32 group;
 526        __u64 block_bitmap;
 527        __u64 inode_bitmap;
 528        __u64 inode_table;
 529        __u32 blocks_count;
 530        __u16 reserved_blocks;
 531        __u16 unused;
 532        __u32 free_blocks_count;
 533};
 534
 535/* Indexes used to index group tables in ext4_new_group_data */
 536enum {
 537        BLOCK_BITMAP = 0,       /* block bitmap */
 538        INODE_BITMAP,           /* inode bitmap */
 539        INODE_TABLE,            /* inode tables */
 540        GROUP_TABLE_COUNT,
 541};
 542
 543/*
 544 * Flags used by ext4_map_blocks()
 545 */
 546        /* Allocate any needed blocks and/or convert an unitialized
 547           extent to be an initialized ext4 */
 548#define EXT4_GET_BLOCKS_CREATE                  0x0001
 549        /* Request the creation of an unitialized extent */
 550#define EXT4_GET_BLOCKS_UNINIT_EXT              0x0002
 551#define EXT4_GET_BLOCKS_CREATE_UNINIT_EXT       (EXT4_GET_BLOCKS_UNINIT_EXT|\
 552                                                 EXT4_GET_BLOCKS_CREATE)
 553        /* Caller is from the delayed allocation writeout path,
 554           so set the magic i_delalloc_reserve_flag after taking the
 555           inode allocation semaphore for */
 556#define EXT4_GET_BLOCKS_DELALLOC_RESERVE        0x0004
 557        /* caller is from the direct IO path, request to creation of an
 558        unitialized extents if not allocated, split the uninitialized
 559        extent if blocks has been preallocated already*/
 560#define EXT4_GET_BLOCKS_PRE_IO                  0x0008
 561#define EXT4_GET_BLOCKS_CONVERT                 0x0010
 562#define EXT4_GET_BLOCKS_IO_CREATE_EXT           (EXT4_GET_BLOCKS_PRE_IO|\
 563                                         EXT4_GET_BLOCKS_CREATE_UNINIT_EXT)
 564        /* Convert extent to initialized after IO complete */
 565#define EXT4_GET_BLOCKS_IO_CONVERT_EXT          (EXT4_GET_BLOCKS_CONVERT|\
 566                                         EXT4_GET_BLOCKS_CREATE_UNINIT_EXT)
 567        /* Punch out blocks of an extent */
 568#define EXT4_GET_BLOCKS_PUNCH_OUT_EXT           0x0020
 569        /* Don't normalize allocation size (used for fallocate) */
 570#define EXT4_GET_BLOCKS_NO_NORMALIZE            0x0040
 571        /* Request will not result in inode size update (user for fallocate) */
 572#define EXT4_GET_BLOCKS_KEEP_SIZE               0x0080
 573        /* Do not take i_data_sem locking in ext4_map_blocks */
 574#define EXT4_GET_BLOCKS_NO_LOCK                 0x0100
 575
 576/*
 577 * Flags used by ext4_free_blocks
 578 */
 579#define EXT4_FREE_BLOCKS_METADATA       0x0001
 580#define EXT4_FREE_BLOCKS_FORGET         0x0002
 581#define EXT4_FREE_BLOCKS_VALIDATED      0x0004
 582#define EXT4_FREE_BLOCKS_NO_QUOT_UPDATE 0x0008
 583#define EXT4_FREE_BLOCKS_NOFREE_FIRST_CLUSTER   0x0010
 584#define EXT4_FREE_BLOCKS_NOFREE_LAST_CLUSTER    0x0020
 585
 586/*
 587 * Flags used by ext4_discard_partial_page_buffers
 588 */
 589#define EXT4_DISCARD_PARTIAL_PG_ZERO_UNMAPPED   0x0001
 590
 591/*
 592 * ioctl commands
 593 */
 594#define EXT4_IOC_GETFLAGS               FS_IOC_GETFLAGS
 595#define EXT4_IOC_SETFLAGS               FS_IOC_SETFLAGS
 596#define EXT4_IOC_GETVERSION             _IOR('f', 3, long)
 597#define EXT4_IOC_SETVERSION             _IOW('f', 4, long)
 598#define EXT4_IOC_GETVERSION_OLD         FS_IOC_GETVERSION
 599#define EXT4_IOC_SETVERSION_OLD         FS_IOC_SETVERSION
 600#define EXT4_IOC_GETRSVSZ               _IOR('f', 5, long)
 601#define EXT4_IOC_SETRSVSZ               _IOW('f', 6, long)
 602#define EXT4_IOC_GROUP_EXTEND           _IOW('f', 7, unsigned long)
 603#define EXT4_IOC_GROUP_ADD              _IOW('f', 8, struct ext4_new_group_input)
 604#define EXT4_IOC_MIGRATE                _IO('f', 9)
 605 /* note ioctl 10 reserved for an early version of the FIEMAP ioctl */
 606 /* note ioctl 11 reserved for filesystem-independent FIEMAP ioctl */
 607#define EXT4_IOC_ALLOC_DA_BLKS          _IO('f', 12)
 608#define EXT4_IOC_MOVE_EXT               _IOWR('f', 15, struct move_extent)
 609#define EXT4_IOC_RESIZE_FS              _IOW('f', 16, __u64)
 610
 611#if defined(__KERNEL__) && defined(CONFIG_COMPAT)
 612/*
 613 * ioctl commands in 32 bit emulation
 614 */
 615#define EXT4_IOC32_GETFLAGS             FS_IOC32_GETFLAGS
 616#define EXT4_IOC32_SETFLAGS             FS_IOC32_SETFLAGS
 617#define EXT4_IOC32_GETVERSION           _IOR('f', 3, int)
 618#define EXT4_IOC32_SETVERSION           _IOW('f', 4, int)
 619#define EXT4_IOC32_GETRSVSZ             _IOR('f', 5, int)
 620#define EXT4_IOC32_SETRSVSZ             _IOW('f', 6, int)
 621#define EXT4_IOC32_GROUP_EXTEND         _IOW('f', 7, unsigned int)
 622#define EXT4_IOC32_GROUP_ADD            _IOW('f', 8, struct compat_ext4_new_group_input)
 623#define EXT4_IOC32_GETVERSION_OLD       FS_IOC32_GETVERSION
 624#define EXT4_IOC32_SETVERSION_OLD       FS_IOC32_SETVERSION
 625#endif
 626
 627/* Max physical block we can address w/o extents */
 628#define EXT4_MAX_BLOCK_FILE_PHYS        0xFFFFFFFF
 629
 630/*
 631 * Structure of an inode on the disk
 632 */
 633struct ext4_inode {
 634        __le16  i_mode;         /* File mode */
 635        __le16  i_uid;          /* Low 16 bits of Owner Uid */
 636        __le32  i_size_lo;      /* Size in bytes */
 637        __le32  i_atime;        /* Access time */
 638        __le32  i_ctime;        /* Inode Change time */
 639        __le32  i_mtime;        /* Modification time */
 640        __le32  i_dtime;        /* Deletion Time */
 641        __le16  i_gid;          /* Low 16 bits of Group Id */
 642        __le16  i_links_count;  /* Links count */
 643        __le32  i_blocks_lo;    /* Blocks count */
 644        __le32  i_flags;        /* File flags */
 645        union {
 646                struct {
 647                        __le32  l_i_version;
 648                } linux1;
 649                struct {
 650                        __u32  h_i_translator;
 651                } hurd1;
 652                struct {
 653                        __u32  m_i_reserved1;
 654                } masix1;
 655        } osd1;                         /* OS dependent 1 */
 656        __le32  i_block[EXT4_N_BLOCKS];/* Pointers to blocks */
 657        __le32  i_generation;   /* File version (for NFS) */
 658        __le32  i_file_acl_lo;  /* File ACL */
 659        __le32  i_size_high;
 660        __le32  i_obso_faddr;   /* Obsoleted fragment address */
 661        union {
 662                struct {
 663                        __le16  l_i_blocks_high; /* were l_i_reserved1 */
 664                        __le16  l_i_file_acl_high;
 665                        __le16  l_i_uid_high;   /* these 2 fields */
 666                        __le16  l_i_gid_high;   /* were reserved2[0] */
 667                        __le16  l_i_checksum_lo;/* crc32c(uuid+inum+inode) LE */
 668                        __le16  l_i_reserved;
 669                } linux2;
 670                struct {
 671                        __le16  h_i_reserved1;  /* Obsoleted fragment number/size which are removed in ext4 */
 672                        __u16   h_i_mode_high;
 673                        __u16   h_i_uid_high;
 674                        __u16   h_i_gid_high;
 675                        __u32   h_i_author;
 676                } hurd2;
 677                struct {
 678                        __le16  h_i_reserved1;  /* Obsoleted fragment number/size which are removed in ext4 */
 679                        __le16  m_i_file_acl_high;
 680                        __u32   m_i_reserved2[2];
 681                } masix2;
 682        } osd2;                         /* OS dependent 2 */
 683        __le16  i_extra_isize;
 684        __le16  i_checksum_hi;  /* crc32c(uuid+inum+inode) BE */
 685        __le32  i_ctime_extra;  /* extra Change time      (nsec << 2 | epoch) */
 686        __le32  i_mtime_extra;  /* extra Modification time(nsec << 2 | epoch) */
 687        __le32  i_atime_extra;  /* extra Access time      (nsec << 2 | epoch) */
 688        __le32  i_crtime;       /* File Creation time */
 689        __le32  i_crtime_extra; /* extra FileCreationtime (nsec << 2 | epoch) */
 690        __le32  i_version_hi;   /* high 32 bits for 64-bit version */
 691};
 692
 693struct move_extent {
 694        __u32 reserved;         /* should be zero */
 695        __u32 donor_fd;         /* donor file descriptor */
 696        __u64 orig_start;       /* logical start offset in block for orig */
 697        __u64 donor_start;      /* logical start offset in block for donor */
 698        __u64 len;              /* block length to be moved */
 699        __u64 moved_len;        /* moved block length */
 700};
 701
 702#define EXT4_EPOCH_BITS 2
 703#define EXT4_EPOCH_MASK ((1 << EXT4_EPOCH_BITS) - 1)
 704#define EXT4_NSEC_MASK  (~0UL << EXT4_EPOCH_BITS)
 705
 706/*
 707 * Extended fields will fit into an inode if the filesystem was formatted
 708 * with large inodes (-I 256 or larger) and there are not currently any EAs
 709 * consuming all of the available space. For new inodes we always reserve
 710 * enough space for the kernel's known extended fields, but for inodes
 711 * created with an old kernel this might not have been the case. None of
 712 * the extended inode fields is critical for correct filesystem operation.
 713 * This macro checks if a certain field fits in the inode. Note that
 714 * inode-size = GOOD_OLD_INODE_SIZE + i_extra_isize
 715 */
 716#define EXT4_FITS_IN_INODE(ext4_inode, einode, field)   \
 717        ((offsetof(typeof(*ext4_inode), field) +        \
 718          sizeof((ext4_inode)->field))                  \
 719        <= (EXT4_GOOD_OLD_INODE_SIZE +                  \
 720            (einode)->i_extra_isize))                   \
 721
 722static inline __le32 ext4_encode_extra_time(struct timespec *time)
 723{
 724       return cpu_to_le32((sizeof(time->tv_sec) > 4 ?
 725                           (time->tv_sec >> 32) & EXT4_EPOCH_MASK : 0) |
 726                          ((time->tv_nsec << EXT4_EPOCH_BITS) & EXT4_NSEC_MASK));
 727}
 728
 729static inline void ext4_decode_extra_time(struct timespec *time, __le32 extra)
 730{
 731       if (sizeof(time->tv_sec) > 4)
 732               time->tv_sec |= (__u64)(le32_to_cpu(extra) & EXT4_EPOCH_MASK)
 733                               << 32;
 734       time->tv_nsec = (le32_to_cpu(extra) & EXT4_NSEC_MASK) >> EXT4_EPOCH_BITS;
 735}
 736
 737#define EXT4_INODE_SET_XTIME(xtime, inode, raw_inode)                          \
 738do {                                                                           \
 739        (raw_inode)->xtime = cpu_to_le32((inode)->xtime.tv_sec);               \
 740        if (EXT4_FITS_IN_INODE(raw_inode, EXT4_I(inode), xtime ## _extra))     \
 741                (raw_inode)->xtime ## _extra =                                 \
 742                                ext4_encode_extra_time(&(inode)->xtime);       \
 743} while (0)
 744
 745#define EXT4_EINODE_SET_XTIME(xtime, einode, raw_inode)                        \
 746do {                                                                           \
 747        if (EXT4_FITS_IN_INODE(raw_inode, einode, xtime))                      \
 748                (raw_inode)->xtime = cpu_to_le32((einode)->xtime.tv_sec);      \
 749        if (EXT4_FITS_IN_INODE(raw_inode, einode, xtime ## _extra))            \
 750                (raw_inode)->xtime ## _extra =                                 \
 751                                ext4_encode_extra_time(&(einode)->xtime);      \
 752} while (0)
 753
 754#define EXT4_INODE_GET_XTIME(xtime, inode, raw_inode)                          \
 755do {                                                                           \
 756        (inode)->xtime.tv_sec = (signed)le32_to_cpu((raw_inode)->xtime);       \
 757        if (EXT4_FITS_IN_INODE(raw_inode, EXT4_I(inode), xtime ## _extra))     \
 758                ext4_decode_extra_time(&(inode)->xtime,                        \
 759                                       raw_inode->xtime ## _extra);            \
 760        else                                                                   \
 761                (inode)->xtime.tv_nsec = 0;                                    \
 762} while (0)
 763
 764#define EXT4_EINODE_GET_XTIME(xtime, einode, raw_inode)                        \
 765do {                                                                           \
 766        if (EXT4_FITS_IN_INODE(raw_inode, einode, xtime))                      \
 767                (einode)->xtime.tv_sec =                                       \
 768                        (signed)le32_to_cpu((raw_inode)->xtime);               \
 769        if (EXT4_FITS_IN_INODE(raw_inode, einode, xtime ## _extra))            \
 770                ext4_decode_extra_time(&(einode)->xtime,                       \
 771                                       raw_inode->xtime ## _extra);            \
 772        else                                                                   \
 773                (einode)->xtime.tv_nsec = 0;                                   \
 774} while (0)
 775
 776#define i_disk_version osd1.linux1.l_i_version
 777
 778#if defined(__KERNEL__) || defined(__linux__)
 779#define i_reserved1     osd1.linux1.l_i_reserved1
 780#define i_file_acl_high osd2.linux2.l_i_file_acl_high
 781#define i_blocks_high   osd2.linux2.l_i_blocks_high
 782#define i_uid_low       i_uid
 783#define i_gid_low       i_gid
 784#define i_uid_high      osd2.linux2.l_i_uid_high
 785#define i_gid_high      osd2.linux2.l_i_gid_high
 786#define i_checksum_lo   osd2.linux2.l_i_checksum_lo
 787
 788#elif defined(__GNU__)
 789
 790#define i_translator    osd1.hurd1.h_i_translator
 791#define i_uid_high      osd2.hurd2.h_i_uid_high
 792#define i_gid_high      osd2.hurd2.h_i_gid_high
 793#define i_author        osd2.hurd2.h_i_author
 794
 795#elif defined(__masix__)
 796
 797#define i_reserved1     osd1.masix1.m_i_reserved1
 798#define i_file_acl_high osd2.masix2.m_i_file_acl_high
 799#define i_reserved2     osd2.masix2.m_i_reserved2
 800
 801#endif /* defined(__KERNEL__) || defined(__linux__) */
 802
 803/*
 804 * storage for cached extent
 805 * If ec_len == 0, then the cache is invalid.
 806 * If ec_start == 0, then the cache represents a gap (null mapping)
 807 */
 808struct ext4_ext_cache {
 809        ext4_fsblk_t    ec_start;
 810        ext4_lblk_t     ec_block;
 811        __u32           ec_len; /* must be 32bit to return holes */
 812};
 813
 814/*
 815 * fourth extended file system inode data in memory
 816 */
 817struct ext4_inode_info {
 818        __le32  i_data[15];     /* unconverted */
 819        __u32   i_dtime;
 820        ext4_fsblk_t    i_file_acl;
 821
 822        /*
 823         * i_block_group is the number of the block group which contains
 824         * this file's inode.  Constant across the lifetime of the inode,
 825         * it is ued for making block allocation decisions - we try to
 826         * place a file's data blocks near its inode block, and new inodes
 827         * near to their parent directory's inode.
 828         */
 829        ext4_group_t    i_block_group;
 830        ext4_lblk_t     i_dir_start_lookup;
 831#if (BITS_PER_LONG < 64)
 832        unsigned long   i_state_flags;          /* Dynamic state flags */
 833#endif
 834        unsigned long   i_flags;
 835
 836#ifdef CONFIG_EXT4_FS_XATTR
 837        /*
 838         * Extended attributes can be read independently of the main file
 839         * data. Taking i_mutex even when reading would cause contention
 840         * between readers of EAs and writers of regular file data, so
 841         * instead we synchronize on xattr_sem when reading or changing
 842         * EAs.
 843         */
 844        struct rw_semaphore xattr_sem;
 845#endif
 846
 847        struct list_head i_orphan;      /* unlinked but open inodes */
 848
 849        /*
 850         * i_disksize keeps track of what the inode size is ON DISK, not
 851         * in memory.  During truncate, i_size is set to the new size by
 852         * the VFS prior to calling ext4_truncate(), but the filesystem won't
 853         * set i_disksize to 0 until the truncate is actually under way.
 854         *
 855         * The intent is that i_disksize always represents the blocks which
 856         * are used by this file.  This allows recovery to restart truncate
 857         * on orphans if we crash during truncate.  We actually write i_disksize
 858         * into the on-disk inode when writing inodes out, instead of i_size.
 859         *
 860         * The only time when i_disksize and i_size may be different is when
 861         * a truncate is in progress.  The only things which change i_disksize
 862         * are ext4_get_block (growth) and ext4_truncate (shrinkth).
 863         */
 864        loff_t  i_disksize;
 865
 866        /*
 867         * i_data_sem is for serialising ext4_truncate() against
 868         * ext4_getblock().  In the 2.4 ext2 design, great chunks of inode's
 869         * data tree are chopped off during truncate. We can't do that in
 870         * ext4 because whenever we perform intermediate commits during
 871         * truncate, the inode and all the metadata blocks *must* be in a
 872         * consistent state which allows truncation of the orphans to restart
 873         * during recovery.  Hence we must fix the get_block-vs-truncate race
 874         * by other means, so we have i_data_sem.
 875         */
 876        struct rw_semaphore i_data_sem;
 877        struct inode vfs_inode;
 878        struct jbd2_inode *jinode;
 879
 880        struct ext4_ext_cache i_cached_extent;
 881        /*
 882         * File creation time. Its function is same as that of
 883         * struct timespec i_{a,c,m}time in the generic inode.
 884         */
 885        struct timespec i_crtime;
 886
 887        /* mballoc */
 888        struct list_head i_prealloc_list;
 889        spinlock_t i_prealloc_lock;
 890
 891        /* ialloc */
 892        ext4_group_t    i_last_alloc_group;
 893
 894        /* allocation reservation info for delalloc */
 895        /* In case of bigalloc, these refer to clusters rather than blocks */
 896        unsigned int i_reserved_data_blocks;
 897        unsigned int i_reserved_meta_blocks;
 898        unsigned int i_allocated_meta_blocks;
 899        ext4_lblk_t i_da_metadata_calc_last_lblock;
 900        int i_da_metadata_calc_len;
 901
 902        /* on-disk additional length */
 903        __u16 i_extra_isize;
 904
 905#ifdef CONFIG_QUOTA
 906        /* quota space reservation, managed internally by quota code */
 907        qsize_t i_reserved_quota;
 908#endif
 909
 910        /* completed IOs that might need unwritten extents handling */
 911        struct list_head i_completed_io_list;
 912        spinlock_t i_completed_io_lock;
 913        atomic_t i_ioend_count; /* Number of outstanding io_end structs */
 914        atomic_t i_unwritten; /* Nr. of inflight conversions pending */
 915
 916        spinlock_t i_block_reservation_lock;
 917
 918        /*
 919         * Transactions that contain inode's metadata needed to complete
 920         * fsync and fdatasync, respectively.
 921         */
 922        tid_t i_sync_tid;
 923        tid_t i_datasync_tid;
 924
 925        /* Precomputed uuid+inum+igen checksum for seeding inode checksums */
 926        __u32 i_csum_seed;
 927};
 928
 929/*
 930 * File system states
 931 */
 932#define EXT4_VALID_FS                   0x0001  /* Unmounted cleanly */
 933#define EXT4_ERROR_FS                   0x0002  /* Errors detected */
 934#define EXT4_ORPHAN_FS                  0x0004  /* Orphans being recovered */
 935
 936/*
 937 * Misc. filesystem flags
 938 */
 939#define EXT2_FLAGS_SIGNED_HASH          0x0001  /* Signed dirhash in use */
 940#define EXT2_FLAGS_UNSIGNED_HASH        0x0002  /* Unsigned dirhash in use */
 941#define EXT2_FLAGS_TEST_FILESYS         0x0004  /* to test development code */
 942
 943/*
 944 * Mount flags
 945 */
 946#define EXT4_MOUNT_GRPID                0x00004 /* Create files with directory's group */
 947#define EXT4_MOUNT_DEBUG                0x00008 /* Some debugging messages */
 948#define EXT4_MOUNT_ERRORS_CONT          0x00010 /* Continue on errors */
 949#define EXT4_MOUNT_ERRORS_RO            0x00020 /* Remount fs ro on errors */
 950#define EXT4_MOUNT_ERRORS_PANIC         0x00040 /* Panic on errors */
 951#define EXT4_MOUNT_ERRORS_MASK          0x00070
 952#define EXT4_MOUNT_MINIX_DF             0x00080 /* Mimics the Minix statfs */
 953#define EXT4_MOUNT_NOLOAD               0x00100 /* Don't use existing journal*/
 954#define EXT4_MOUNT_DATA_FLAGS           0x00C00 /* Mode for data writes: */
 955#define EXT4_MOUNT_JOURNAL_DATA         0x00400 /* Write data to journal */
 956#define EXT4_MOUNT_ORDERED_DATA         0x00800 /* Flush data before commit */
 957#define EXT4_MOUNT_WRITEBACK_DATA       0x00C00 /* No data ordering */
 958#define EXT4_MOUNT_UPDATE_JOURNAL       0x01000 /* Update the journal format */
 959#define EXT4_MOUNT_NO_UID32             0x02000  /* Disable 32-bit UIDs */
 960#define EXT4_MOUNT_XATTR_USER           0x04000 /* Extended user attributes */
 961#define EXT4_MOUNT_POSIX_ACL            0x08000 /* POSIX Access Control Lists */
 962#define EXT4_MOUNT_NO_AUTO_DA_ALLOC     0x10000 /* No auto delalloc mapping */
 963#define EXT4_MOUNT_BARRIER              0x20000 /* Use block barriers */
 964#define EXT4_MOUNT_QUOTA                0x80000 /* Some quota option set */
 965#define EXT4_MOUNT_USRQUOTA             0x100000 /* "old" user quota */
 966#define EXT4_MOUNT_GRPQUOTA             0x200000 /* "old" group quota */
 967#define EXT4_MOUNT_DIOREAD_NOLOCK       0x400000 /* Enable support for dio read nolocking */
 968#define EXT4_MOUNT_JOURNAL_CHECKSUM     0x800000 /* Journal checksums */
 969#define EXT4_MOUNT_JOURNAL_ASYNC_COMMIT 0x1000000 /* Journal Async Commit */
 970#define EXT4_MOUNT_MBLK_IO_SUBMIT       0x4000000 /* multi-block io submits */
 971#define EXT4_MOUNT_DELALLOC             0x8000000 /* Delalloc support */
 972#define EXT4_MOUNT_DATA_ERR_ABORT       0x10000000 /* Abort on file data write */
 973#define EXT4_MOUNT_BLOCK_VALIDITY       0x20000000 /* Block validity checking */
 974#define EXT4_MOUNT_DISCARD              0x40000000 /* Issue DISCARD requests */
 975#define EXT4_MOUNT_INIT_INODE_TABLE     0x80000000 /* Initialize uninitialized itables */
 976
 977#define EXT4_MOUNT2_EXPLICIT_DELALLOC   0x00000001 /* User explicitly
 978                                                      specified delalloc */
 979
 980#define clear_opt(sb, opt)              EXT4_SB(sb)->s_mount_opt &= \
 981                                                ~EXT4_MOUNT_##opt
 982#define set_opt(sb, opt)                EXT4_SB(sb)->s_mount_opt |= \
 983                                                EXT4_MOUNT_##opt
 984#define test_opt(sb, opt)               (EXT4_SB(sb)->s_mount_opt & \
 985                                         EXT4_MOUNT_##opt)
 986
 987#define clear_opt2(sb, opt)             EXT4_SB(sb)->s_mount_opt2 &= \
 988                                                ~EXT4_MOUNT2_##opt
 989#define set_opt2(sb, opt)               EXT4_SB(sb)->s_mount_opt2 |= \
 990                                                EXT4_MOUNT2_##opt
 991#define test_opt2(sb, opt)              (EXT4_SB(sb)->s_mount_opt2 & \
 992                                         EXT4_MOUNT2_##opt)
 993
 994#define ext4_test_and_set_bit           __test_and_set_bit_le
 995#define ext4_set_bit                    __set_bit_le
 996#define ext4_set_bit_atomic             ext2_set_bit_atomic
 997#define ext4_test_and_clear_bit         __test_and_clear_bit_le
 998#define ext4_clear_bit                  __clear_bit_le
 999#define ext4_clear_bit_atomic           ext2_clear_bit_atomic
1000#define ext4_test_bit                   test_bit_le
1001#define ext4_find_next_zero_bit         find_next_zero_bit_le
1002#define ext4_find_next_bit              find_next_bit_le
1003
1004extern void ext4_set_bits(void *bm, int cur, int len);
1005
1006/*
1007 * Maximal mount counts between two filesystem checks
1008 */
1009#define EXT4_DFL_MAX_MNT_COUNT          20      /* Allow 20 mounts */
1010#define EXT4_DFL_CHECKINTERVAL          0       /* Don't use interval check */
1011
1012/*
1013 * Behaviour when detecting errors
1014 */
1015#define EXT4_ERRORS_CONTINUE            1       /* Continue execution */
1016#define EXT4_ERRORS_RO                  2       /* Remount fs read-only */
1017#define EXT4_ERRORS_PANIC               3       /* Panic */
1018#define EXT4_ERRORS_DEFAULT             EXT4_ERRORS_CONTINUE
1019
1020/* Metadata checksum algorithm codes */
1021#define EXT4_CRC32C_CHKSUM              1
1022
1023/*
1024 * Structure of the super block
1025 */
1026struct ext4_super_block {
1027/*00*/  __le32  s_inodes_count;         /* Inodes count */
1028        __le32  s_blocks_count_lo;      /* Blocks count */
1029        __le32  s_r_blocks_count_lo;    /* Reserved blocks count */
1030        __le32  s_free_blocks_count_lo; /* Free blocks count */
1031/*10*/  __le32  s_free_inodes_count;    /* Free inodes count */
1032        __le32  s_first_data_block;     /* First Data Block */
1033        __le32  s_log_block_size;       /* Block size */
1034        __le32  s_log_cluster_size;     /* Allocation cluster size */
1035/*20*/  __le32  s_blocks_per_group;     /* # Blocks per group */
1036        __le32  s_clusters_per_group;   /* # Clusters per group */
1037        __le32  s_inodes_per_group;     /* # Inodes per group */
1038        __le32  s_mtime;                /* Mount time */
1039/*30*/  __le32  s_wtime;                /* Write time */
1040        __le16  s_mnt_count;            /* Mount count */
1041        __le16  s_max_mnt_count;        /* Maximal mount count */
1042        __le16  s_magic;                /* Magic signature */
1043        __le16  s_state;                /* File system state */
1044        __le16  s_errors;               /* Behaviour when detecting errors */
1045        __le16  s_minor_rev_level;      /* minor revision level */
1046/*40*/  __le32  s_lastcheck;            /* time of last check */
1047        __le32  s_checkinterval;        /* max. time between checks */
1048        __le32  s_creator_os;           /* OS */
1049        __le32  s_rev_level;            /* Revision level */
1050/*50*/  __le16  s_def_resuid;           /* Default uid for reserved blocks */
1051        __le16  s_def_resgid;           /* Default gid for reserved blocks */
1052        /*
1053         * These fields are for EXT4_DYNAMIC_REV superblocks only.
1054         *
1055         * Note: the difference between the compatible feature set and
1056         * the incompatible feature set is that if there is a bit set
1057         * in the incompatible feature set that the kernel doesn't
1058         * know about, it should refuse to mount the filesystem.
1059         *
1060         * e2fsck's requirements are more strict; if it doesn't know
1061         * about a feature in either the compatible or incompatible
1062         * feature set, it must abort and not try to meddle with
1063         * things it doesn't understand...
1064         */
1065        __le32  s_first_ino;            /* First non-reserved inode */
1066        __le16  s_inode_size;           /* size of inode structure */
1067        __le16  s_block_group_nr;       /* block group # of this superblock */
1068        __le32  s_feature_compat;       /* compatible feature set */
1069/*60*/  __le32  s_feature_incompat;     /* incompatible feature set */
1070        __le32  s_feature_ro_compat;    /* readonly-compatible feature set */
1071/*68*/  __u8    s_uuid[16];             /* 128-bit uuid for volume */
1072/*78*/  char    s_volume_name[16];      /* volume name */
1073/*88*/  char    s_last_mounted[64];     /* directory where last mounted */
1074/*C8*/  __le32  s_algorithm_usage_bitmap; /* For compression */
1075        /*
1076         * Performance hints.  Directory preallocation should only
1077         * happen if the EXT4_FEATURE_COMPAT_DIR_PREALLOC flag is on.
1078         */
1079        __u8    s_prealloc_blocks;      /* Nr of blocks to try to preallocate*/
1080        __u8    s_prealloc_dir_blocks;  /* Nr to preallocate for dirs */
1081        __le16  s_reserved_gdt_blocks;  /* Per group desc for online growth */
1082        /*
1083         * Journaling support valid if EXT4_FEATURE_COMPAT_HAS_JOURNAL set.
1084         */
1085/*D0*/  __u8    s_journal_uuid[16];     /* uuid of journal superblock */
1086/*E0*/  __le32  s_journal_inum;         /* inode number of journal file */
1087        __le32  s_journal_dev;          /* device number of journal file */
1088        __le32  s_last_orphan;          /* start of list of inodes to delete */
1089        __le32  s_hash_seed[4];         /* HTREE hash seed */
1090        __u8    s_def_hash_version;     /* Default hash version to use */
1091        __u8    s_jnl_backup_type;
1092        __le16  s_desc_size;            /* size of group descriptor */
1093/*100*/ __le32  s_default_mount_opts;
1094        __le32  s_first_meta_bg;        /* First metablock block group */
1095        __le32  s_mkfs_time;            /* When the filesystem was created */
1096        __le32  s_jnl_blocks[17];       /* Backup of the journal inode */
1097        /* 64bit support valid if EXT4_FEATURE_COMPAT_64BIT */
1098/*150*/ __le32  s_blocks_count_hi;      /* Blocks count */
1099        __le32  s_r_blocks_count_hi;    /* Reserved blocks count */
1100        __le32  s_free_blocks_count_hi; /* Free blocks count */
1101        __le16  s_min_extra_isize;      /* All inodes have at least # bytes */
1102        __le16  s_want_extra_isize;     /* New inodes should reserve # bytes */
1103        __le32  s_flags;                /* Miscellaneous flags */
1104        __le16  s_raid_stride;          /* RAID stride */
1105        __le16  s_mmp_update_interval;  /* # seconds to wait in MMP checking */
1106        __le64  s_mmp_block;            /* Block for multi-mount protection */
1107        __le32  s_raid_stripe_width;    /* blocks on all data disks (N*stride)*/
1108        __u8    s_log_groups_per_flex;  /* FLEX_BG group size */
1109        __u8    s_checksum_type;        /* metadata checksum algorithm used */
1110        __le16  s_reserved_pad;
1111        __le64  s_kbytes_written;       /* nr of lifetime kilobytes written */
1112        __le32  s_snapshot_inum;        /* Inode number of active snapshot */
1113        __le32  s_snapshot_id;          /* sequential ID of active snapshot */
1114        __le64  s_snapshot_r_blocks_count; /* reserved blocks for active
1115                                              snapshot's future use */
1116        __le32  s_snapshot_list;        /* inode number of the head of the
1117                                           on-disk snapshot list */
1118#define EXT4_S_ERR_START offsetof(struct ext4_super_block, s_error_count)
1119        __le32  s_error_count;          /* number of fs errors */
1120        __le32  s_first_error_time;     /* first time an error happened */
1121        __le32  s_first_error_ino;      /* inode involved in first error */
1122        __le64  s_first_error_block;    /* block involved of first error */
1123        __u8    s_first_error_func[32]; /* function where the error happened */
1124        __le32  s_first_error_line;     /* line number where error happened */
1125        __le32  s_last_error_time;      /* most recent time of an error */
1126        __le32  s_last_error_ino;       /* inode involved in last error */
1127        __le32  s_last_error_line;      /* line number where error happened */
1128        __le64  s_last_error_block;     /* block involved of last error */
1129        __u8    s_last_error_func[32];  /* function where the error happened */
1130#define EXT4_S_ERR_END offsetof(struct ext4_super_block, s_mount_opts)
1131        __u8    s_mount_opts[64];
1132        __le32  s_usr_quota_inum;       /* inode for tracking user quota */
1133        __le32  s_grp_quota_inum;       /* inode for tracking group quota */
1134        __le32  s_overhead_clusters;    /* overhead blocks/clusters in fs */
1135        __le32  s_reserved[108];        /* Padding to the end of the block */
1136        __le32  s_checksum;             /* crc32c(superblock) */
1137};
1138
1139#define EXT4_S_ERR_LEN (EXT4_S_ERR_END - EXT4_S_ERR_START)
1140
1141#ifdef __KERNEL__
1142
1143/*
1144 * run-time mount flags
1145 */
1146#define EXT4_MF_MNTDIR_SAMPLED  0x0001
1147#define EXT4_MF_FS_ABORTED      0x0002  /* Fatal error detected */
1148
1149/*
1150 * fourth extended-fs super-block data in memory
1151 */
1152struct ext4_sb_info {
1153        unsigned long s_desc_size;      /* Size of a group descriptor in bytes */
1154        unsigned long s_inodes_per_block;/* Number of inodes per block */
1155        unsigned long s_blocks_per_group;/* Number of blocks in a group */
1156        unsigned long s_clusters_per_group; /* Number of clusters in a group */
1157        unsigned long s_inodes_per_group;/* Number of inodes in a group */
1158        unsigned long s_itb_per_group;  /* Number of inode table blocks per group */
1159        unsigned long s_gdb_count;      /* Number of group descriptor blocks */
1160        unsigned long s_desc_per_block; /* Number of group descriptors per block */
1161        ext4_group_t s_groups_count;    /* Number of groups in the fs */
1162        ext4_group_t s_blockfile_groups;/* Groups acceptable for non-extent files */
1163        unsigned long s_overhead;  /* # of fs overhead clusters */
1164        unsigned int s_cluster_ratio;   /* Number of blocks per cluster */
1165        unsigned int s_cluster_bits;    /* log2 of s_cluster_ratio */
1166        loff_t s_bitmap_maxbytes;       /* max bytes for bitmap files */
1167        struct buffer_head * s_sbh;     /* Buffer containing the super block */
1168        struct ext4_super_block *s_es;  /* Pointer to the super block in the buffer */
1169        struct buffer_head **s_group_desc;
1170        unsigned int s_mount_opt;
1171        unsigned int s_mount_opt2;
1172        unsigned int s_mount_flags;
1173        unsigned int s_def_mount_opt;
1174        ext4_fsblk_t s_sb_block;
1175        kuid_t s_resuid;
1176        kgid_t s_resgid;
1177        unsigned short s_mount_state;
1178        unsigned short s_pad;
1179        int s_addr_per_block_bits;
1180        int s_desc_per_block_bits;
1181        int s_inode_size;
1182        int s_first_ino;
1183        unsigned int s_inode_readahead_blks;
1184        unsigned int s_inode_goal;
1185        spinlock_t s_next_gen_lock;
1186        u32 s_next_generation;
1187        u32 s_hash_seed[4];
1188        int s_def_hash_version;
1189        int s_hash_unsigned;    /* 3 if hash should be signed, 0 if not */
1190        struct percpu_counter s_freeclusters_counter;
1191        struct percpu_counter s_freeinodes_counter;
1192        struct percpu_counter s_dirs_counter;
1193        struct percpu_counter s_dirtyclusters_counter;
1194        struct blockgroup_lock *s_blockgroup_lock;
1195        struct proc_dir_entry *s_proc;
1196        struct kobject s_kobj;
1197        struct completion s_kobj_unregister;
1198        struct super_block *s_sb;
1199
1200        /* Journaling */
1201        struct journal_s *s_journal;
1202        struct list_head s_orphan;
1203        struct mutex s_orphan_lock;
1204        unsigned long s_resize_flags;           /* Flags indicating if there
1205                                                   is a resizer */
1206        unsigned long s_commit_interval;
1207        u32 s_max_batch_time;
1208        u32 s_min_batch_time;
1209        struct block_device *journal_bdev;
1210#ifdef CONFIG_QUOTA
1211        char *s_qf_names[MAXQUOTAS];            /* Names of quota files with journalled quota */
1212        int s_jquota_fmt;                       /* Format of quota to use */
1213#endif
1214        unsigned int s_want_extra_isize; /* New inodes should reserve # bytes */
1215        struct rb_root system_blks;
1216
1217#ifdef EXTENTS_STATS
1218        /* ext4 extents stats */
1219        unsigned long s_ext_min;
1220        unsigned long s_ext_max;
1221        unsigned long s_depth_max;
1222        spinlock_t s_ext_stats_lock;
1223        unsigned long s_ext_blocks;
1224        unsigned long s_ext_extents;
1225#endif
1226
1227        /* for buddy allocator */
1228        struct ext4_group_info ***s_group_info;
1229        struct inode *s_buddy_cache;
1230        spinlock_t s_md_lock;
1231        unsigned short *s_mb_offsets;
1232        unsigned int *s_mb_maxs;
1233        unsigned int s_group_info_size;
1234
1235        /* tunables */
1236        unsigned long s_stripe;
1237        unsigned int s_mb_stream_request;
1238        unsigned int s_mb_max_to_scan;
1239        unsigned int s_mb_min_to_scan;
1240        unsigned int s_mb_stats;
1241        unsigned int s_mb_order2_reqs;
1242        unsigned int s_mb_group_prealloc;
1243        unsigned int s_max_writeback_mb_bump;
1244        unsigned int s_max_dir_size_kb;
1245        /* where last allocation was done - for stream allocation */
1246        unsigned long s_mb_last_group;
1247        unsigned long s_mb_last_start;
1248
1249        /* stats for buddy allocator */
1250        atomic_t s_bal_reqs;    /* number of reqs with len > 1 */
1251        atomic_t s_bal_success; /* we found long enough chunks */
1252        atomic_t s_bal_allocated;       /* in blocks */
1253        atomic_t s_bal_ex_scanned;      /* total extents scanned */
1254        atomic_t s_bal_goals;   /* goal hits */
1255        atomic_t s_bal_breaks;  /* too long searches */
1256        atomic_t s_bal_2orders; /* 2^order hits */
1257        spinlock_t s_bal_lock;
1258        unsigned long s_mb_buddies_generated;
1259        unsigned long long s_mb_generation_time;
1260        atomic_t s_mb_lost_chunks;
1261        atomic_t s_mb_preallocated;
1262        atomic_t s_mb_discarded;
1263        atomic_t s_lock_busy;
1264
1265        /* locality groups */
1266        struct ext4_locality_group __percpu *s_locality_groups;
1267
1268        /* for write statistics */
1269        unsigned long s_sectors_written_start;
1270        u64 s_kbytes_written;
1271
1272        /* the size of zero-out chunk */
1273        unsigned int s_extent_max_zeroout_kb;
1274
1275        unsigned int s_log_groups_per_flex;
1276        struct flex_groups *s_flex_groups;
1277        ext4_group_t s_flex_groups_allocated;
1278
1279        /* workqueue for dio unwritten */
1280        struct workqueue_struct *dio_unwritten_wq;
1281
1282        /* timer for periodic error stats printing */
1283        struct timer_list s_err_report;
1284
1285        /* Lazy inode table initialization info */
1286        struct ext4_li_request *s_li_request;
1287        /* Wait multiplier for lazy initialization thread */
1288        unsigned int s_li_wait_mult;
1289
1290        /* Kernel thread for multiple mount protection */
1291        struct task_struct *s_mmp_tsk;
1292
1293        /* record the last minlen when FITRIM is called. */
1294        atomic_t s_last_trim_minblks;
1295
1296        /* Reference to checksum algorithm driver via cryptoapi */
1297        struct crypto_shash *s_chksum_driver;
1298
1299        /* Precomputed FS UUID checksum for seeding other checksums */
1300        __u32 s_csum_seed;
1301};
1302
1303static inline struct ext4_sb_info *EXT4_SB(struct super_block *sb)
1304{
1305        return sb->s_fs_info;
1306}
1307static inline struct ext4_inode_info *EXT4_I(struct inode *inode)
1308{
1309        return container_of(inode, struct ext4_inode_info, vfs_inode);
1310}
1311
1312static inline struct timespec ext4_current_time(struct inode *inode)
1313{
1314        return (inode->i_sb->s_time_gran < NSEC_PER_SEC) ?
1315                current_fs_time(inode->i_sb) : CURRENT_TIME_SEC;
1316}
1317
1318static inline int ext4_valid_inum(struct super_block *sb, unsigned long ino)
1319{
1320        return ino == EXT4_ROOT_INO ||
1321                ino == EXT4_USR_QUOTA_INO ||
1322                ino == EXT4_GRP_QUOTA_INO ||
1323                ino == EXT4_JOURNAL_INO ||
1324                ino == EXT4_RESIZE_INO ||
1325                (ino >= EXT4_FIRST_INO(sb) &&
1326                 ino <= le32_to_cpu(EXT4_SB(sb)->s_es->s_inodes_count));
1327}
1328
1329static inline void ext4_set_io_unwritten_flag(struct inode *inode,
1330                                              struct ext4_io_end *io_end)
1331{
1332        if (!(io_end->flag & EXT4_IO_END_UNWRITTEN)) {
1333                io_end->flag |= EXT4_IO_END_UNWRITTEN;
1334                atomic_inc(&EXT4_I(inode)->i_unwritten);
1335        }
1336}
1337
1338static inline ext4_io_end_t *ext4_inode_aio(struct inode *inode)
1339{
1340        return inode->i_private;
1341}
1342
1343static inline void ext4_inode_aio_set(struct inode *inode, ext4_io_end_t *io)
1344{
1345        inode->i_private = io;
1346}
1347
1348/*
1349 * Inode dynamic state flags
1350 */
1351enum {
1352        EXT4_STATE_JDATA,               /* journaled data exists */
1353        EXT4_STATE_NEW,                 /* inode is newly created */
1354        EXT4_STATE_XATTR,               /* has in-inode xattrs */
1355        EXT4_STATE_NO_EXPAND,           /* No space for expansion */
1356        EXT4_STATE_DA_ALLOC_CLOSE,      /* Alloc DA blks on close */
1357        EXT4_STATE_EXT_MIGRATE,         /* Inode is migrating */
1358        EXT4_STATE_DIO_UNWRITTEN,       /* need convert on dio done*/
1359        EXT4_STATE_NEWENTRY,            /* File just added to dir */
1360        EXT4_STATE_DELALLOC_RESERVED,   /* blks already reserved for delalloc */
1361        EXT4_STATE_DIOREAD_LOCK,        /* Disable support for dio read
1362                                           nolocking */
1363};
1364
1365#define EXT4_INODE_BIT_FNS(name, field, offset)                         \
1366static inline int ext4_test_inode_##name(struct inode *inode, int bit)  \
1367{                                                                       \
1368        return test_bit(bit + (offset), &EXT4_I(inode)->i_##field);     \
1369}                                                                       \
1370static inline void ext4_set_inode_##name(struct inode *inode, int bit)  \
1371{                                                                       \
1372        set_bit(bit + (offset), &EXT4_I(inode)->i_##field);             \
1373}                                                                       \
1374static inline void ext4_clear_inode_##name(struct inode *inode, int bit) \
1375{                                                                       \
1376        clear_bit(bit + (offset), &EXT4_I(inode)->i_##field);           \
1377}
1378
1379EXT4_INODE_BIT_FNS(flag, flags, 0)
1380#if (BITS_PER_LONG < 64)
1381EXT4_INODE_BIT_FNS(state, state_flags, 0)
1382
1383static inline void ext4_clear_state_flags(struct ext4_inode_info *ei)
1384{
1385        (ei)->i_state_flags = 0;
1386}
1387#else
1388EXT4_INODE_BIT_FNS(state, flags, 32)
1389
1390static inline void ext4_clear_state_flags(struct ext4_inode_info *ei)
1391{
1392        /* We depend on the fact that callers will set i_flags */
1393}
1394#endif
1395#else
1396/* Assume that user mode programs are passing in an ext4fs superblock, not
1397 * a kernel struct super_block.  This will allow us to call the feature-test
1398 * macros from user land. */
1399#define EXT4_SB(sb)     (sb)
1400#endif
1401
1402#define NEXT_ORPHAN(inode) EXT4_I(inode)->i_dtime
1403
1404/*
1405 * Codes for operating systems
1406 */
1407#define EXT4_OS_LINUX           0
1408#define EXT4_OS_HURD            1
1409#define EXT4_OS_MASIX           2
1410#define EXT4_OS_FREEBSD         3
1411#define EXT4_OS_LITES           4
1412
1413/*
1414 * Revision levels
1415 */
1416#define EXT4_GOOD_OLD_REV       0       /* The good old (original) format */
1417#define EXT4_DYNAMIC_REV        1       /* V2 format w/ dynamic inode sizes */
1418
1419#define EXT4_CURRENT_REV        EXT4_GOOD_OLD_REV
1420#define EXT4_MAX_SUPP_REV       EXT4_DYNAMIC_REV
1421
1422#define EXT4_GOOD_OLD_INODE_SIZE 128
1423
1424/*
1425 * Feature set definitions
1426 */
1427
1428#define EXT4_HAS_COMPAT_FEATURE(sb,mask)                        \
1429        ((EXT4_SB(sb)->s_es->s_feature_compat & cpu_to_le32(mask)) != 0)
1430#define EXT4_HAS_RO_COMPAT_FEATURE(sb,mask)                     \
1431        ((EXT4_SB(sb)->s_es->s_feature_ro_compat & cpu_to_le32(mask)) != 0)
1432#define EXT4_HAS_INCOMPAT_FEATURE(sb,mask)                      \
1433        ((EXT4_SB(sb)->s_es->s_feature_incompat & cpu_to_le32(mask)) != 0)
1434#define EXT4_SET_COMPAT_FEATURE(sb,mask)                        \
1435        EXT4_SB(sb)->s_es->s_feature_compat |= cpu_to_le32(mask)
1436#define EXT4_SET_RO_COMPAT_FEATURE(sb,mask)                     \
1437        EXT4_SB(sb)->s_es->s_feature_ro_compat |= cpu_to_le32(mask)
1438#define EXT4_SET_INCOMPAT_FEATURE(sb,mask)                      \
1439        EXT4_SB(sb)->s_es->s_feature_incompat |= cpu_to_le32(mask)
1440#define EXT4_CLEAR_COMPAT_FEATURE(sb,mask)                      \
1441        EXT4_SB(sb)->s_es->s_feature_compat &= ~cpu_to_le32(mask)
1442#define EXT4_CLEAR_RO_COMPAT_FEATURE(sb,mask)                   \
1443        EXT4_SB(sb)->s_es->s_feature_ro_compat &= ~cpu_to_le32(mask)
1444#define EXT4_CLEAR_INCOMPAT_FEATURE(sb,mask)                    \
1445        EXT4_SB(sb)->s_es->s_feature_incompat &= ~cpu_to_le32(mask)
1446
1447#define EXT4_FEATURE_COMPAT_DIR_PREALLOC        0x0001
1448#define EXT4_FEATURE_COMPAT_IMAGIC_INODES       0x0002
1449#define EXT4_FEATURE_COMPAT_HAS_JOURNAL         0x0004
1450#define EXT4_FEATURE_COMPAT_EXT_ATTR            0x0008
1451#define EXT4_FEATURE_COMPAT_RESIZE_INODE        0x0010
1452#define EXT4_FEATURE_COMPAT_DIR_INDEX           0x0020
1453
1454#define EXT4_FEATURE_RO_COMPAT_SPARSE_SUPER     0x0001
1455#define EXT4_FEATURE_RO_COMPAT_LARGE_FILE       0x0002
1456#define EXT4_FEATURE_RO_COMPAT_BTREE_DIR        0x0004
1457#define EXT4_FEATURE_RO_COMPAT_HUGE_FILE        0x0008
1458#define EXT4_FEATURE_RO_COMPAT_GDT_CSUM         0x0010
1459#define EXT4_FEATURE_RO_COMPAT_DIR_NLINK        0x0020
1460#define EXT4_FEATURE_RO_COMPAT_EXTRA_ISIZE      0x0040
1461#define EXT4_FEATURE_RO_COMPAT_QUOTA            0x0100
1462#define EXT4_FEATURE_RO_COMPAT_BIGALLOC         0x0200
1463/*
1464 * METADATA_CSUM also enables group descriptor checksums (GDT_CSUM).  When
1465 * METADATA_CSUM is set, group descriptor checksums use the same algorithm as
1466 * all other data structures' checksums.  However, the METADATA_CSUM and
1467 * GDT_CSUM bits are mutually exclusive.
1468 */
1469#define EXT4_FEATURE_RO_COMPAT_METADATA_CSUM    0x0400
1470
1471#define EXT4_FEATURE_INCOMPAT_COMPRESSION       0x0001
1472#define EXT4_FEATURE_INCOMPAT_FILETYPE          0x0002
1473#define EXT4_FEATURE_INCOMPAT_RECOVER           0x0004 /* Needs recovery */
1474#define EXT4_FEATURE_INCOMPAT_JOURNAL_DEV       0x0008 /* Journal device */
1475#define EXT4_FEATURE_INCOMPAT_META_BG           0x0010
1476#define EXT4_FEATURE_INCOMPAT_EXTENTS           0x0040 /* extents support */
1477#define EXT4_FEATURE_INCOMPAT_64BIT             0x0080
1478#define EXT4_FEATURE_INCOMPAT_MMP               0x0100
1479#define EXT4_FEATURE_INCOMPAT_FLEX_BG           0x0200
1480#define EXT4_FEATURE_INCOMPAT_EA_INODE          0x0400 /* EA in inode */
1481#define EXT4_FEATURE_INCOMPAT_DIRDATA           0x1000 /* data in dirent */
1482#define EXT4_FEATURE_INCOMPAT_BG_USE_META_CSUM  0x2000 /* use crc32c for bg */
1483#define EXT4_FEATURE_INCOMPAT_LARGEDIR          0x4000 /* >2GB or 3-lvl htree */
1484#define EXT4_FEATURE_INCOMPAT_INLINEDATA        0x8000 /* data in inode */
1485
1486#define EXT2_FEATURE_COMPAT_SUPP        EXT4_FEATURE_COMPAT_EXT_ATTR
1487#define EXT2_FEATURE_INCOMPAT_SUPP      (EXT4_FEATURE_INCOMPAT_FILETYPE| \
1488                                         EXT4_FEATURE_INCOMPAT_META_BG)
1489#define EXT2_FEATURE_RO_COMPAT_SUPP     (EXT4_FEATURE_RO_COMPAT_SPARSE_SUPER| \
1490                                         EXT4_FEATURE_RO_COMPAT_LARGE_FILE| \
1491                                         EXT4_FEATURE_RO_COMPAT_BTREE_DIR)
1492
1493#define EXT3_FEATURE_COMPAT_SUPP        EXT4_FEATURE_COMPAT_EXT_ATTR
1494#define EXT3_FEATURE_INCOMPAT_SUPP      (EXT4_FEATURE_INCOMPAT_FILETYPE| \
1495                                         EXT4_FEATURE_INCOMPAT_RECOVER| \
1496                                         EXT4_FEATURE_INCOMPAT_META_BG)
1497#define EXT3_FEATURE_RO_COMPAT_SUPP     (EXT4_FEATURE_RO_COMPAT_SPARSE_SUPER| \
1498                                         EXT4_FEATURE_RO_COMPAT_LARGE_FILE| \
1499                                         EXT4_FEATURE_RO_COMPAT_BTREE_DIR)
1500
1501#define EXT4_FEATURE_COMPAT_SUPP        EXT2_FEATURE_COMPAT_EXT_ATTR
1502#define EXT4_FEATURE_INCOMPAT_SUPP      (EXT4_FEATURE_INCOMPAT_FILETYPE| \
1503                                         EXT4_FEATURE_INCOMPAT_RECOVER| \
1504                                         EXT4_FEATURE_INCOMPAT_META_BG| \
1505                                         EXT4_FEATURE_INCOMPAT_EXTENTS| \
1506                                         EXT4_FEATURE_INCOMPAT_64BIT| \
1507                                         EXT4_FEATURE_INCOMPAT_FLEX_BG| \
1508                                         EXT4_FEATURE_INCOMPAT_MMP)
1509#define EXT4_FEATURE_RO_COMPAT_SUPP     (EXT4_FEATURE_RO_COMPAT_SPARSE_SUPER| \
1510                                         EXT4_FEATURE_RO_COMPAT_LARGE_FILE| \
1511                                         EXT4_FEATURE_RO_COMPAT_GDT_CSUM| \
1512                                         EXT4_FEATURE_RO_COMPAT_DIR_NLINK | \
1513                                         EXT4_FEATURE_RO_COMPAT_EXTRA_ISIZE | \
1514                                         EXT4_FEATURE_RO_COMPAT_BTREE_DIR |\
1515                                         EXT4_FEATURE_RO_COMPAT_HUGE_FILE |\
1516                                         EXT4_FEATURE_RO_COMPAT_BIGALLOC |\
1517                                         EXT4_FEATURE_RO_COMPAT_METADATA_CSUM|\
1518                                         EXT4_FEATURE_RO_COMPAT_QUOTA)
1519
1520/*
1521 * Default values for user and/or group using reserved blocks
1522 */
1523#define EXT4_DEF_RESUID         0
1524#define EXT4_DEF_RESGID         0
1525
1526#define EXT4_DEF_INODE_READAHEAD_BLKS   32
1527
1528/*
1529 * Default mount options
1530 */
1531#define EXT4_DEFM_DEBUG         0x0001
1532#define EXT4_DEFM_BSDGROUPS     0x0002
1533#define EXT4_DEFM_XATTR_USER    0x0004
1534#define EXT4_DEFM_ACL           0x0008
1535#define EXT4_DEFM_UID16         0x0010
1536#define EXT4_DEFM_JMODE         0x0060
1537#define EXT4_DEFM_JMODE_DATA    0x0020
1538#define EXT4_DEFM_JMODE_ORDERED 0x0040
1539#define EXT4_DEFM_JMODE_WBACK   0x0060
1540#define EXT4_DEFM_NOBARRIER     0x0100
1541#define EXT4_DEFM_BLOCK_VALIDITY 0x0200
1542#define EXT4_DEFM_DISCARD       0x0400
1543#define EXT4_DEFM_NODELALLOC    0x0800
1544
1545/*
1546 * Default journal batch times
1547 */
1548#define EXT4_DEF_MIN_BATCH_TIME 0
1549#define EXT4_DEF_MAX_BATCH_TIME 15000 /* 15ms */
1550
1551/*
1552 * Minimum number of groups in a flexgroup before we separate out
1553 * directories into the first block group of a flexgroup
1554 */
1555#define EXT4_FLEX_SIZE_DIR_ALLOC_SCHEME 4
1556
1557/*
1558 * Structure of a directory entry
1559 */
1560#define EXT4_NAME_LEN 255
1561
1562struct ext4_dir_entry {
1563        __le32  inode;                  /* Inode number */
1564        __le16  rec_len;                /* Directory entry length */
1565        __le16  name_len;               /* Name length */
1566        char    name[EXT4_NAME_LEN];    /* File name */
1567};
1568
1569/*
1570 * The new version of the directory entry.  Since EXT4 structures are
1571 * stored in intel byte order, and the name_len field could never be
1572 * bigger than 255 chars, it's safe to reclaim the extra byte for the
1573 * file_type field.
1574 */
1575struct ext4_dir_entry_2 {
1576        __le32  inode;                  /* Inode number */
1577        __le16  rec_len;                /* Directory entry length */
1578        __u8    name_len;               /* Name length */
1579        __u8    file_type;
1580        char    name[EXT4_NAME_LEN];    /* File name */
1581};
1582
1583/*
1584 * This is a bogus directory entry at the end of each leaf block that
1585 * records checksums.
1586 */
1587struct ext4_dir_entry_tail {
1588        __le32  det_reserved_zero1;     /* Pretend to be unused */
1589        __le16  det_rec_len;            /* 12 */
1590        __u8    det_reserved_zero2;     /* Zero name length */
1591        __u8    det_reserved_ft;        /* 0xDE, fake file type */
1592        __le32  det_checksum;           /* crc32c(uuid+inum+dirblock) */
1593};
1594
1595/*
1596 * Ext4 directory file types.  Only the low 3 bits are used.  The
1597 * other bits are reserved for now.
1598 */
1599#define EXT4_FT_UNKNOWN         0
1600#define EXT4_FT_REG_FILE        1
1601#define EXT4_FT_DIR             2
1602#define EXT4_FT_CHRDEV          3
1603#define EXT4_FT_BLKDEV          4
1604#define EXT4_FT_FIFO            5
1605#define EXT4_FT_SOCK            6
1606#define EXT4_FT_SYMLINK         7
1607
1608#define EXT4_FT_MAX             8
1609
1610#define EXT4_FT_DIR_CSUM        0xDE
1611
1612/*
1613 * EXT4_DIR_PAD defines the directory entries boundaries
1614 *
1615 * NOTE: It must be a multiple of 4
1616 */
1617#define EXT4_DIR_PAD                    4
1618#define EXT4_DIR_ROUND                  (EXT4_DIR_PAD - 1)
1619#define EXT4_DIR_REC_LEN(name_len)      (((name_len) + 8 + EXT4_DIR_ROUND) & \
1620                                         ~EXT4_DIR_ROUND)
1621#define EXT4_MAX_REC_LEN                ((1<<16)-1)
1622
1623/*
1624 * If we ever get support for fs block sizes > page_size, we'll need
1625 * to remove the #if statements in the next two functions...
1626 */
1627static inline unsigned int
1628ext4_rec_len_from_disk(__le16 dlen, unsigned blocksize)
1629{
1630        unsigned len = le16_to_cpu(dlen);
1631
1632#if (PAGE_CACHE_SIZE >= 65536)
1633        if (len == EXT4_MAX_REC_LEN || len == 0)
1634                return blocksize;
1635        return (len & 65532) | ((len & 3) << 16);
1636#else
1637        return len;
1638#endif
1639}
1640
1641static inline __le16 ext4_rec_len_to_disk(unsigned len, unsigned blocksize)
1642{
1643        if ((len > blocksize) || (blocksize > (1 << 18)) || (len & 3))
1644                BUG();
1645#if (PAGE_CACHE_SIZE >= 65536)
1646        if (len < 65536)
1647                return cpu_to_le16(len);
1648        if (len == blocksize) {
1649                if (blocksize == 65536)
1650                        return cpu_to_le16(EXT4_MAX_REC_LEN);
1651                else
1652                        return cpu_to_le16(0);
1653        }
1654        return cpu_to_le16((len & 65532) | ((len >> 16) & 3));
1655#else
1656        return cpu_to_le16(len);
1657#endif
1658}
1659
1660/*
1661 * Hash Tree Directory indexing
1662 * (c) Daniel Phillips, 2001
1663 */
1664
1665#define is_dx(dir) (EXT4_HAS_COMPAT_FEATURE(dir->i_sb, \
1666                                      EXT4_FEATURE_COMPAT_DIR_INDEX) && \
1667                    ext4_test_inode_flag((dir), EXT4_INODE_INDEX))
1668#define EXT4_DIR_LINK_MAX(dir) (!is_dx(dir) && (dir)->i_nlink >= EXT4_LINK_MAX)
1669#define EXT4_DIR_LINK_EMPTY(dir) ((dir)->i_nlink == 2 || (dir)->i_nlink == 1)
1670
1671/* Legal values for the dx_root hash_version field: */
1672
1673#define DX_HASH_LEGACY          0
1674#define DX_HASH_HALF_MD4        1
1675#define DX_HASH_TEA             2
1676#define DX_HASH_LEGACY_UNSIGNED 3
1677#define DX_HASH_HALF_MD4_UNSIGNED       4
1678#define DX_HASH_TEA_UNSIGNED            5
1679
1680static inline u32 ext4_chksum(struct ext4_sb_info *sbi, u32 crc,
1681                              const void *address, unsigned int length)
1682{
1683        struct {
1684                struct shash_desc shash;
1685                char ctx[4];
1686        } desc;
1687        int err;
1688
1689        BUG_ON(crypto_shash_descsize(sbi->s_chksum_driver)!=sizeof(desc.ctx));
1690
1691        desc.shash.tfm = sbi->s_chksum_driver;
1692        desc.shash.flags = 0;
1693        *(u32 *)desc.ctx = crc;
1694
1695        err = crypto_shash_update(&desc.shash, address, length);
1696        BUG_ON(err);
1697
1698        return *(u32 *)desc.ctx;
1699}
1700
1701#ifdef __KERNEL__
1702
1703/* hash info structure used by the directory hash */
1704struct dx_hash_info
1705{
1706        u32             hash;
1707        u32             minor_hash;
1708        int             hash_version;
1709        u32             *seed;
1710};
1711
1712
1713/* 32 and 64 bit signed EOF for dx directories */
1714#define EXT4_HTREE_EOF_32BIT   ((1UL  << (32 - 1)) - 1)
1715#define EXT4_HTREE_EOF_64BIT   ((1ULL << (64 - 1)) - 1)
1716
1717
1718/*
1719 * Control parameters used by ext4_htree_next_block
1720 */
1721#define HASH_NB_ALWAYS          1
1722
1723
1724/*
1725 * Describe an inode's exact location on disk and in memory
1726 */
1727struct ext4_iloc
1728{
1729        struct buffer_head *bh;
1730        unsigned long offset;
1731        ext4_group_t block_group;
1732};
1733
1734static inline struct ext4_inode *ext4_raw_inode(struct ext4_iloc *iloc)
1735{
1736        return (struct ext4_inode *) (iloc->bh->b_data + iloc->offset);
1737}
1738
1739/*
1740 * This structure is stuffed into the struct file's private_data field
1741 * for directories.  It is where we put information so that we can do
1742 * readdir operations in hash tree order.
1743 */
1744struct dir_private_info {
1745        struct rb_root  root;
1746        struct rb_node  *curr_node;
1747        struct fname    *extra_fname;
1748        loff_t          last_pos;
1749        __u32           curr_hash;
1750        __u32           curr_minor_hash;
1751        __u32           next_hash;
1752};
1753
1754/* calculate the first block number of the group */
1755static inline ext4_fsblk_t
1756ext4_group_first_block_no(struct super_block *sb, ext4_group_t group_no)
1757{
1758        return group_no * (ext4_fsblk_t)EXT4_BLOCKS_PER_GROUP(sb) +
1759                le32_to_cpu(EXT4_SB(sb)->s_es->s_first_data_block);
1760}
1761
1762/*
1763 * Special error return code only used by dx_probe() and its callers.
1764 */
1765#define ERR_BAD_DX_DIR  -75000
1766
1767void ext4_get_group_no_and_offset(struct super_block *sb, ext4_fsblk_t blocknr,
1768                        ext4_group_t *blockgrpp, ext4_grpblk_t *offsetp);
1769
1770/*
1771 * Timeout and state flag for lazy initialization inode thread.
1772 */
1773#define EXT4_DEF_LI_WAIT_MULT                   10
1774#define EXT4_DEF_LI_MAX_START_DELAY             5
1775#define EXT4_LAZYINIT_QUIT                      0x0001
1776#define EXT4_LAZYINIT_RUNNING                   0x0002
1777
1778/*
1779 * Lazy inode table initialization info
1780 */
1781struct ext4_lazy_init {
1782        unsigned long           li_state;
1783        struct list_head        li_request_list;
1784        struct mutex            li_list_mtx;
1785};
1786
1787struct ext4_li_request {
1788        struct super_block      *lr_super;
1789        struct ext4_sb_info     *lr_sbi;
1790        ext4_group_t            lr_next_group;
1791        struct list_head        lr_request;
1792        unsigned long           lr_next_sched;
1793        unsigned long           lr_timeout;
1794};
1795
1796struct ext4_features {
1797        struct kobject f_kobj;
1798        struct completion f_kobj_unregister;
1799};
1800
1801/*
1802 * This structure will be used for multiple mount protection. It will be
1803 * written into the block number saved in the s_mmp_block field in the
1804 * superblock. Programs that check MMP should assume that if
1805 * SEQ_FSCK (or any unknown code above SEQ_MAX) is present then it is NOT safe
1806 * to use the filesystem, regardless of how old the timestamp is.
1807 */
1808#define EXT4_MMP_MAGIC     0x004D4D50U /* ASCII for MMP */
1809#define EXT4_MMP_SEQ_CLEAN 0xFF4D4D50U /* mmp_seq value for clean unmount */
1810#define EXT4_MMP_SEQ_FSCK  0xE24D4D50U /* mmp_seq value when being fscked */
1811#define EXT4_MMP_SEQ_MAX   0xE24D4D4FU /* maximum valid mmp_seq value */
1812
1813struct mmp_struct {
1814        __le32  mmp_magic;              /* Magic number for MMP */
1815        __le32  mmp_seq;                /* Sequence no. updated periodically */
1816
1817        /*
1818         * mmp_time, mmp_nodename & mmp_bdevname are only used for information
1819         * purposes and do not affect the correctness of the algorithm
1820         */
1821        __le64  mmp_time;               /* Time last updated */
1822        char    mmp_nodename[64];       /* Node which last updated MMP block */
1823        char    mmp_bdevname[32];       /* Bdev which last updated MMP block */
1824
1825        /*
1826         * mmp_check_interval is used to verify if the MMP block has been
1827         * updated on the block device. The value is updated based on the
1828         * maximum time to write the MMP block during an update cycle.
1829         */
1830        __le16  mmp_check_interval;
1831
1832        __le16  mmp_pad1;
1833        __le32  mmp_pad2[226];
1834        __le32  mmp_checksum;           /* crc32c(uuid+mmp_block) */
1835};
1836
1837/* arguments passed to the mmp thread */
1838struct mmpd_data {
1839        struct buffer_head *bh; /* bh from initial read_mmp_block() */
1840        struct super_block *sb;  /* super block of the fs */
1841};
1842
1843/*
1844 * Check interval multiplier
1845 * The MMP block is written every update interval and initially checked every
1846 * update interval x the multiplier (the value is then adapted based on the
1847 * write latency). The reason is that writes can be delayed under load and we
1848 * don't want readers to incorrectly assume that the filesystem is no longer
1849 * in use.
1850 */
1851#define EXT4_MMP_CHECK_MULT             2UL
1852
1853/*
1854 * Minimum interval for MMP checking in seconds.
1855 */
1856#define EXT4_MMP_MIN_CHECK_INTERVAL     5UL
1857
1858/*
1859 * Maximum interval for MMP checking in seconds.
1860 */
1861#define EXT4_MMP_MAX_CHECK_INTERVAL     300UL
1862
1863/*
1864 * Function prototypes
1865 */
1866
1867/*
1868 * Ok, these declarations are also in <linux/kernel.h> but none of the
1869 * ext4 source programs needs to include it so they are duplicated here.
1870 */
1871# define NORET_TYPE     /**/
1872# define ATTRIB_NORET   __attribute__((noreturn))
1873# define NORET_AND      noreturn,
1874
1875/* bitmap.c */
1876extern unsigned int ext4_count_free(char *bitmap, unsigned numchars);
1877void ext4_inode_bitmap_csum_set(struct super_block *sb, ext4_group_t group,
1878                                struct ext4_group_desc *gdp,
1879                                struct buffer_head *bh, int sz);
1880int ext4_inode_bitmap_csum_verify(struct super_block *sb, ext4_group_t group,
1881                                  struct ext4_group_desc *gdp,
1882                                  struct buffer_head *bh, int sz);
1883void ext4_block_bitmap_csum_set(struct super_block *sb, ext4_group_t group,
1884                                struct ext4_group_desc *gdp,
1885                                struct buffer_head *bh);
1886int ext4_block_bitmap_csum_verify(struct super_block *sb, ext4_group_t group,
1887                                  struct ext4_group_desc *gdp,
1888                                  struct buffer_head *bh);
1889
1890/* balloc.c */
1891extern void ext4_validate_block_bitmap(struct super_block *sb,
1892                                       struct ext4_group_desc *desc,
1893                                       unsigned int block_group,
1894                                       struct buffer_head *bh);
1895extern unsigned int ext4_block_group(struct super_block *sb,
1896                        ext4_fsblk_t blocknr);
1897extern ext4_grpblk_t ext4_block_group_offset(struct super_block *sb,
1898                        ext4_fsblk_t blocknr);
1899extern int ext4_bg_has_super(struct super_block *sb, ext4_group_t group);
1900extern unsigned long ext4_bg_num_gdb(struct super_block *sb,
1901                        ext4_group_t group);
1902extern ext4_fsblk_t ext4_new_meta_blocks(handle_t *handle, struct inode *inode,
1903                                         ext4_fsblk_t goal,
1904                                         unsigned int flags,
1905                                         unsigned long *count,
1906                                         int *errp);
1907extern int ext4_claim_free_clusters(struct ext4_sb_info *sbi,
1908                                    s64 nclusters, unsigned int flags);
1909extern ext4_fsblk_t ext4_count_free_clusters(struct super_block *);
1910extern void ext4_check_blocks_bitmap(struct super_block *);
1911extern struct ext4_group_desc * ext4_get_group_desc(struct super_block * sb,
1912                                                    ext4_group_t block_group,
1913                                                    struct buffer_head ** bh);
1914extern int ext4_should_retry_alloc(struct super_block *sb, int *retries);
1915
1916extern struct buffer_head *ext4_read_block_bitmap_nowait(struct super_block *sb,
1917                                                ext4_group_t block_group);
1918extern int ext4_wait_block_bitmap(struct super_block *sb,
1919                                  ext4_group_t block_group,
1920                                  struct buffer_head *bh);
1921extern struct buffer_head *ext4_read_block_bitmap(struct super_block *sb,
1922                                                  ext4_group_t block_group);
1923extern void ext4_init_block_bitmap(struct super_block *sb,
1924                                   struct buffer_head *bh,
1925                                   ext4_group_t group,
1926                                   struct ext4_group_desc *desc);
1927extern unsigned ext4_free_clusters_after_init(struct super_block *sb,
1928                                              ext4_group_t block_group,
1929                                              struct ext4_group_desc *gdp);
1930extern unsigned ext4_num_overhead_clusters(struct super_block *sb,
1931                                           ext4_group_t block_group,
1932                                           struct ext4_group_desc *gdp);
1933ext4_fsblk_t ext4_inode_to_goal_block(struct inode *);
1934
1935/* dir.c */
1936extern int __ext4_check_dir_entry(const char *, unsigned int, struct inode *,
1937                                  struct file *,
1938                                  struct ext4_dir_entry_2 *,
1939                                  struct buffer_head *, unsigned int);
1940#define ext4_check_dir_entry(dir, filp, de, bh, offset)                 \
1941        unlikely(__ext4_check_dir_entry(__func__, __LINE__, (dir), (filp), \
1942                                        (de), (bh), (offset)))
1943extern int ext4_htree_store_dirent(struct file *dir_file, __u32 hash,
1944                                    __u32 minor_hash,
1945                                    struct ext4_dir_entry_2 *dirent);
1946extern void ext4_htree_free_dir_info(struct dir_private_info *p);
1947
1948/* fsync.c */
1949extern int ext4_sync_file(struct file *, loff_t, loff_t, int);
1950extern int ext4_flush_unwritten_io(struct inode *);
1951
1952/* hash.c */
1953extern int ext4fs_dirhash(const char *name, int len, struct
1954                          dx_hash_info *hinfo);
1955
1956/* ialloc.c */
1957extern struct inode *ext4_new_inode(handle_t *, struct inode *, umode_t,
1958                                    const struct qstr *qstr, __u32 goal,
1959                                    uid_t *owner);
1960extern void ext4_free_inode(handle_t *, struct inode *);
1961extern struct inode * ext4_orphan_get(struct super_block *, unsigned long);
1962extern unsigned long ext4_count_free_inodes(struct super_block *);
1963extern unsigned long ext4_count_dirs(struct super_block *);
1964extern void ext4_check_inodes_bitmap(struct super_block *);
1965extern void ext4_mark_bitmap_end(int start_bit, int end_bit, char *bitmap);
1966extern int ext4_init_inode_table(struct super_block *sb,
1967                                 ext4_group_t group, int barrier);
1968extern void ext4_end_bitmap_read(struct buffer_head *bh, int uptodate);
1969
1970/* mballoc.c */
1971extern long ext4_mb_stats;
1972extern long ext4_mb_max_to_scan;
1973extern int ext4_mb_init(struct super_block *);
1974extern int ext4_mb_release(struct super_block *);
1975extern ext4_fsblk_t ext4_mb_new_blocks(handle_t *,
1976                                struct ext4_allocation_request *, int *);
1977extern int ext4_mb_reserve_blocks(struct super_block *, int);
1978extern void ext4_discard_preallocations(struct inode *);
1979extern int __init ext4_init_mballoc(void);
1980extern void ext4_exit_mballoc(void);
1981extern void ext4_free_blocks(handle_t *handle, struct inode *inode,
1982                             struct buffer_head *bh, ext4_fsblk_t block,
1983                             unsigned long count, int flags);
1984extern int ext4_mb_alloc_groupinfo(struct super_block *sb,
1985                                   ext4_group_t ngroups);
1986extern int ext4_mb_add_groupinfo(struct super_block *sb,
1987                ext4_group_t i, struct ext4_group_desc *desc);
1988extern int ext4_group_add_blocks(handle_t *handle, struct super_block *sb,
1989                                ext4_fsblk_t block, unsigned long count);
1990extern int ext4_trim_fs(struct super_block *, struct fstrim_range *);
1991
1992/* inode.c */
1993struct buffer_head *ext4_getblk(handle_t *, struct inode *,
1994                                                ext4_lblk_t, int, int *);
1995struct buffer_head *ext4_bread(handle_t *, struct inode *,
1996                                                ext4_lblk_t, int, int *);
1997int ext4_get_block(struct inode *inode, sector_t iblock,
1998                                struct buffer_head *bh_result, int create);
1999
2000extern struct inode *ext4_iget(struct super_block *, unsigned long);
2001extern int  ext4_write_inode(struct inode *, struct writeback_control *);
2002extern int  ext4_setattr(struct dentry *, struct iattr *);
2003extern int  ext4_getattr(struct vfsmount *mnt, struct dentry *dentry,
2004                                struct kstat *stat);
2005extern void ext4_evict_inode(struct inode *);
2006extern void ext4_clear_inode(struct inode *);
2007extern int  ext4_sync_inode(handle_t *, struct inode *);
2008extern void ext4_dirty_inode(struct inode *, int);
2009extern int ext4_change_inode_journal_flag(struct inode *, int);
2010extern int ext4_get_inode_loc(struct inode *, struct ext4_iloc *);
2011extern int ext4_can_truncate(struct inode *inode);
2012extern void ext4_truncate(struct inode *);
2013extern int ext4_punch_hole(struct file *file, loff_t offset, loff_t length);
2014extern int ext4_truncate_restart_trans(handle_t *, struct inode *, int nblocks);
2015extern void ext4_set_inode_flags(struct inode *);
2016extern void ext4_get_inode_flags(struct ext4_inode_info *);
2017extern int ext4_alloc_da_blocks(struct inode *inode);
2018extern void ext4_set_aops(struct inode *inode);
2019extern int ext4_writepage_trans_blocks(struct inode *);
2020extern int ext4_chunk_trans_blocks(struct inode *, int nrblocks);
2021extern int ext4_discard_partial_page_buffers(handle_t *handle,
2022                struct address_space *mapping, loff_t from,
2023                loff_t length, int flags);
2024extern int ext4_page_mkwrite(struct vm_area_struct *vma, struct vm_fault *vmf);
2025extern qsize_t *ext4_get_reserved_space(struct inode *inode);
2026extern void ext4_da_update_reserve_space(struct inode *inode,
2027                                        int used, int quota_claim);
2028
2029/* indirect.c */
2030extern int ext4_ind_map_blocks(handle_t *handle, struct inode *inode,
2031                                struct ext4_map_blocks *map, int flags);
2032extern ssize_t ext4_ind_direct_IO(int rw, struct kiocb *iocb,
2033                                const struct iovec *iov, loff_t offset,
2034                                unsigned long nr_segs);
2035extern int ext4_ind_calc_metadata_amount(struct inode *inode, sector_t lblock);
2036extern int ext4_ind_trans_blocks(struct inode *inode, int nrblocks, int chunk);
2037extern void ext4_ind_truncate(struct inode *inode);
2038
2039/* ioctl.c */
2040extern long ext4_ioctl(struct file *, unsigned int, unsigned long);
2041extern long ext4_compat_ioctl(struct file *, unsigned int, unsigned long);
2042
2043/* migrate.c */
2044extern int ext4_ext_migrate(struct inode *);
2045
2046/* namei.c */
2047extern int ext4_dirent_csum_verify(struct inode *inode,
2048                                   struct ext4_dir_entry *dirent);
2049extern int ext4_orphan_add(handle_t *, struct inode *);
2050extern int ext4_orphan_del(handle_t *, struct inode *);
2051extern int ext4_htree_fill_tree(struct file *dir_file, __u32 start_hash,
2052                                __u32 start_minor_hash, __u32 *next_hash);
2053
2054/* resize.c */
2055extern int ext4_group_add(struct super_block *sb,
2056                                struct ext4_new_group_data *input);
2057extern int ext4_group_extend(struct super_block *sb,
2058                                struct ext4_super_block *es,
2059                                ext4_fsblk_t n_blocks_count);
2060extern int ext4_resize_fs(struct super_block *sb, ext4_fsblk_t n_blocks_count);
2061
2062/* super.c */
2063extern int ext4_calculate_overhead(struct super_block *sb);
2064extern int ext4_superblock_csum_verify(struct super_block *sb,
2065                                       struct ext4_super_block *es);
2066extern void ext4_superblock_csum_set(struct super_block *sb);
2067extern void *ext4_kvmalloc(size_t size, gfp_t flags);
2068extern void *ext4_kvzalloc(size_t size, gfp_t flags);
2069extern void ext4_kvfree(void *ptr);
2070extern int ext4_alloc_flex_bg_array(struct super_block *sb,
2071                                    ext4_group_t ngroup);
2072extern __printf(4, 5)
2073void __ext4_error(struct super_block *, const char *, unsigned int,
2074                  const char *, ...);
2075#define ext4_error(sb, message...)      __ext4_error(sb, __func__,      \
2076                                                     __LINE__, ## message)
2077extern __printf(5, 6)
2078void ext4_error_inode(struct inode *, const char *, unsigned int, ext4_fsblk_t,
2079                      const char *, ...);
2080extern __printf(5, 6)
2081void ext4_error_file(struct file *, const char *, unsigned int, ext4_fsblk_t,
2082                     const char *, ...);
2083extern void __ext4_std_error(struct super_block *, const char *,
2084                             unsigned int, int);
2085extern __printf(4, 5)
2086void __ext4_abort(struct super_block *, const char *, unsigned int,
2087                  const char *, ...);
2088#define ext4_abort(sb, message...)      __ext4_abort(sb, __func__, \
2089                                                       __LINE__, ## message)
2090extern __printf(4, 5)
2091void __ext4_warning(struct super_block *, const char *, unsigned int,
2092                    const char *, ...);
2093#define ext4_warning(sb, message...)    __ext4_warning(sb, __func__, \
2094                                                       __LINE__, ## message)
2095extern __printf(3, 4)
2096void ext4_msg(struct super_block *, const char *, const char *, ...);
2097extern void __dump_mmp_msg(struct super_block *, struct mmp_struct *mmp,
2098                           const char *, unsigned int, const char *);
2099#define dump_mmp_msg(sb, mmp, msg)      __dump_mmp_msg(sb, mmp, __func__, \
2100                                                       __LINE__, msg)
2101extern __printf(7, 8)
2102void __ext4_grp_locked_error(const char *, unsigned int,
2103                             struct super_block *, ext4_group_t,
2104                             unsigned long, ext4_fsblk_t,
2105                             const char *, ...);
2106#define ext4_grp_locked_error(sb, grp, message...) \
2107        __ext4_grp_locked_error(__func__, __LINE__, (sb), (grp), ## message)
2108extern void ext4_update_dynamic_rev(struct super_block *sb);
2109extern int ext4_update_compat_feature(handle_t *handle, struct super_block *sb,
2110                                        __u32 compat);
2111extern int ext4_update_rocompat_feature(handle_t *handle,
2112                                        struct super_block *sb, __u32 rocompat);
2113extern int ext4_update_incompat_feature(handle_t *handle,
2114                                        struct super_block *sb, __u32 incompat);
2115extern ext4_fsblk_t ext4_block_bitmap(struct super_block *sb,
2116                                      struct ext4_group_desc *bg);
2117extern ext4_fsblk_t ext4_inode_bitmap(struct super_block *sb,
2118                                      struct ext4_group_desc *bg);
2119extern ext4_fsblk_t ext4_inode_table(struct super_block *sb,
2120                                     struct ext4_group_desc *bg);
2121extern __u32 ext4_free_group_clusters(struct super_block *sb,
2122                                      struct ext4_group_desc *bg);
2123extern __u32 ext4_free_inodes_count(struct super_block *sb,
2124                                 struct ext4_group_desc *bg);
2125extern __u32 ext4_used_dirs_count(struct super_block *sb,
2126                                struct ext4_group_desc *bg);
2127extern __u32 ext4_itable_unused_count(struct super_block *sb,
2128                                   struct ext4_group_desc *bg);
2129extern void ext4_block_bitmap_set(struct super_block *sb,
2130                                  struct ext4_group_desc *bg, ext4_fsblk_t blk);
2131extern void ext4_inode_bitmap_set(struct super_block *sb,
2132                                  struct ext4_group_desc *bg, ext4_fsblk_t blk);
2133extern void ext4_inode_table_set(struct super_block *sb,
2134                                 struct ext4_group_desc *bg, ext4_fsblk_t blk);
2135extern void ext4_free_group_clusters_set(struct super_block *sb,
2136                                         struct ext4_group_desc *bg,
2137                                         __u32 count);
2138extern void ext4_free_inodes_set(struct super_block *sb,
2139                                struct ext4_group_desc *bg, __u32 count);
2140extern void ext4_used_dirs_set(struct super_block *sb,
2141                                struct ext4_group_desc *bg, __u32 count);
2142extern void ext4_itable_unused_set(struct super_block *sb,
2143                                   struct ext4_group_desc *bg, __u32 count);
2144extern int ext4_group_desc_csum_verify(struct super_block *sb, __u32 group,
2145                                       struct ext4_group_desc *gdp);
2146extern void ext4_group_desc_csum_set(struct super_block *sb, __u32 group,
2147                                     struct ext4_group_desc *gdp);
2148
2149static inline int ext4_has_group_desc_csum(struct super_block *sb)
2150{
2151        return EXT4_HAS_RO_COMPAT_FEATURE(sb,
2152                                          EXT4_FEATURE_RO_COMPAT_GDT_CSUM |
2153                                          EXT4_FEATURE_RO_COMPAT_METADATA_CSUM);
2154}
2155
2156static inline ext4_fsblk_t ext4_blocks_count(struct ext4_super_block *es)
2157{
2158        return ((ext4_fsblk_t)le32_to_cpu(es->s_blocks_count_hi) << 32) |
2159                le32_to_cpu(es->s_blocks_count_lo);
2160}
2161
2162static inline ext4_fsblk_t ext4_r_blocks_count(struct ext4_super_block *es)
2163{
2164        return ((ext4_fsblk_t)le32_to_cpu(es->s_r_blocks_count_hi) << 32) |
2165                le32_to_cpu(es->s_r_blocks_count_lo);
2166}
2167
2168static inline ext4_fsblk_t ext4_free_blocks_count(struct ext4_super_block *es)
2169{
2170        return ((ext4_fsblk_t)le32_to_cpu(es->s_free_blocks_count_hi) << 32) |
2171                le32_to_cpu(es->s_free_blocks_count_lo);
2172}
2173
2174static inline void ext4_blocks_count_set(struct ext4_super_block *es,
2175                                         ext4_fsblk_t blk)
2176{
2177        es->s_blocks_count_lo = cpu_to_le32((u32)blk);
2178        es->s_blocks_count_hi = cpu_to_le32(blk >> 32);
2179}
2180
2181static inline void ext4_free_blocks_count_set(struct ext4_super_block *es,
2182                                              ext4_fsblk_t blk)
2183{
2184        es->s_free_blocks_count_lo = cpu_to_le32((u32)blk);
2185        es->s_free_blocks_count_hi = cpu_to_le32(blk >> 32);
2186}
2187
2188static inline void ext4_r_blocks_count_set(struct ext4_super_block *es,
2189                                           ext4_fsblk_t blk)
2190{
2191        es->s_r_blocks_count_lo = cpu_to_le32((u32)blk);
2192        es->s_r_blocks_count_hi = cpu_to_le32(blk >> 32);
2193}
2194
2195static inline loff_t ext4_isize(struct ext4_inode *raw_inode)
2196{
2197        if (S_ISREG(le16_to_cpu(raw_inode->i_mode)))
2198                return ((loff_t)le32_to_cpu(raw_inode->i_size_high) << 32) |
2199                        le32_to_cpu(raw_inode->i_size_lo);
2200        else
2201                return (loff_t) le32_to_cpu(raw_inode->i_size_lo);
2202}
2203
2204static inline void ext4_isize_set(struct ext4_inode *raw_inode, loff_t i_size)
2205{
2206        raw_inode->i_size_lo = cpu_to_le32(i_size);
2207        raw_inode->i_size_high = cpu_to_le32(i_size >> 32);
2208}
2209
2210static inline
2211struct ext4_group_info *ext4_get_group_info(struct super_block *sb,
2212                                            ext4_group_t group)
2213{
2214         struct ext4_group_info ***grp_info;
2215         long indexv, indexh;
2216         grp_info = EXT4_SB(sb)->s_group_info;
2217         indexv = group >> (EXT4_DESC_PER_BLOCK_BITS(sb));
2218         indexh = group & ((EXT4_DESC_PER_BLOCK(sb)) - 1);
2219         return grp_info[indexv][indexh];
2220}
2221
2222/*
2223 * Reading s_groups_count requires using smp_rmb() afterwards.  See
2224 * the locking protocol documented in the comments of ext4_group_add()
2225 * in resize.c
2226 */
2227static inline ext4_group_t ext4_get_groups_count(struct super_block *sb)
2228{
2229        ext4_group_t    ngroups = EXT4_SB(sb)->s_groups_count;
2230
2231        smp_rmb();
2232        return ngroups;
2233}
2234
2235static inline ext4_group_t ext4_flex_group(struct ext4_sb_info *sbi,
2236                                             ext4_group_t block_group)
2237{
2238        return block_group >> sbi->s_log_groups_per_flex;
2239}
2240
2241static inline unsigned int ext4_flex_bg_size(struct ext4_sb_info *sbi)
2242{
2243        return 1 << sbi->s_log_groups_per_flex;
2244}
2245
2246#define ext4_std_error(sb, errno)                               \
2247do {                                                            \
2248        if ((errno))                                            \
2249                __ext4_std_error((sb), __func__, __LINE__, (errno));    \
2250} while (0)
2251
2252#ifdef CONFIG_SMP
2253/* Each CPU can accumulate percpu_counter_batch clusters in their local
2254 * counters. So we need to make sure we have free clusters more
2255 * than percpu_counter_batch  * nr_cpu_ids. Also add a window of 4 times.
2256 */
2257#define EXT4_FREECLUSTERS_WATERMARK (4 * (percpu_counter_batch * nr_cpu_ids))
2258#else
2259#define EXT4_FREECLUSTERS_WATERMARK 0
2260#endif
2261
2262static inline void ext4_update_i_disksize(struct inode *inode, loff_t newsize)
2263{
2264        /*
2265         * XXX: replace with spinlock if seen contended -bzzz
2266         */
2267        down_write(&EXT4_I(inode)->i_data_sem);
2268        if (newsize > EXT4_I(inode)->i_disksize)
2269                EXT4_I(inode)->i_disksize = newsize;
2270        up_write(&EXT4_I(inode)->i_data_sem);
2271        return ;
2272}
2273
2274struct ext4_group_info {
2275        unsigned long   bb_state;
2276        struct rb_root  bb_free_root;
2277        ext4_grpblk_t   bb_first_free;  /* first free block */
2278        ext4_grpblk_t   bb_free;        /* total free blocks */
2279        ext4_grpblk_t   bb_fragments;   /* nr of freespace fragments */
2280        ext4_grpblk_t   bb_largest_free_order;/* order of largest frag in BG */
2281        struct          list_head bb_prealloc_list;
2282#ifdef DOUBLE_CHECK
2283        void            *bb_bitmap;
2284#endif
2285        struct rw_semaphore alloc_sem;
2286        ext4_grpblk_t   bb_counters[];  /* Nr of free power-of-two-block
2287                                         * regions, index is order.
2288                                         * bb_counters[3] = 5 means
2289                                         * 5 free 8-block regions. */
2290};
2291
2292#define EXT4_GROUP_INFO_NEED_INIT_BIT           0
2293#define EXT4_GROUP_INFO_WAS_TRIMMED_BIT         1
2294
2295#define EXT4_MB_GRP_NEED_INIT(grp)      \
2296        (test_bit(EXT4_GROUP_INFO_NEED_INIT_BIT, &((grp)->bb_state)))
2297
2298#define EXT4_MB_GRP_WAS_TRIMMED(grp)    \
2299        (test_bit(EXT4_GROUP_INFO_WAS_TRIMMED_BIT, &((grp)->bb_state)))
2300#define EXT4_MB_GRP_SET_TRIMMED(grp)    \
2301        (set_bit(EXT4_GROUP_INFO_WAS_TRIMMED_BIT, &((grp)->bb_state)))
2302#define EXT4_MB_GRP_CLEAR_TRIMMED(grp)  \
2303        (clear_bit(EXT4_GROUP_INFO_WAS_TRIMMED_BIT, &((grp)->bb_state)))
2304
2305#define EXT4_MAX_CONTENTION             8
2306#define EXT4_CONTENTION_THRESHOLD       2
2307
2308static inline spinlock_t *ext4_group_lock_ptr(struct super_block *sb,
2309                                              ext4_group_t group)
2310{
2311        return bgl_lock_ptr(EXT4_SB(sb)->s_blockgroup_lock, group);
2312}
2313
2314/*
2315 * Returns true if the filesystem is busy enough that attempts to
2316 * access the block group locks has run into contention.
2317 */
2318static inline int ext4_fs_is_busy(struct ext4_sb_info *sbi)
2319{
2320        return (atomic_read(&sbi->s_lock_busy) > EXT4_CONTENTION_THRESHOLD);
2321}
2322
2323static inline void ext4_lock_group(struct super_block *sb, ext4_group_t group)
2324{
2325        spinlock_t *lock = ext4_group_lock_ptr(sb, group);
2326        if (spin_trylock(lock))
2327                /*
2328                 * We're able to grab the lock right away, so drop the
2329                 * lock contention counter.
2330                 */
2331                atomic_add_unless(&EXT4_SB(sb)->s_lock_busy, -1, 0);
2332        else {
2333                /*
2334                 * The lock is busy, so bump the contention counter,
2335                 * and then wait on the spin lock.
2336                 */
2337                atomic_add_unless(&EXT4_SB(sb)->s_lock_busy, 1,
2338                                  EXT4_MAX_CONTENTION);
2339                spin_lock(lock);
2340        }
2341}
2342
2343static inline void ext4_unlock_group(struct super_block *sb,
2344                                        ext4_group_t group)
2345{
2346        spin_unlock(ext4_group_lock_ptr(sb, group));
2347}
2348
2349/*
2350 * Block validity checking
2351 */
2352#define ext4_check_indirect_blockref(inode, bh)                         \
2353        ext4_check_blockref(__func__, __LINE__, inode,                  \
2354                            (__le32 *)(bh)->b_data,                     \
2355                            EXT4_ADDR_PER_BLOCK((inode)->i_sb))
2356
2357#define ext4_ind_check_inode(inode)                                     \
2358        ext4_check_blockref(__func__, __LINE__, inode,                  \
2359                            EXT4_I(inode)->i_data,                      \
2360                            EXT4_NDIR_BLOCKS)
2361
2362/*
2363 * Inodes and files operations
2364 */
2365
2366/* dir.c */
2367extern const struct file_operations ext4_dir_operations;
2368
2369/* file.c */
2370extern const struct inode_operations ext4_file_inode_operations;
2371extern const struct file_operations ext4_file_operations;
2372extern loff_t ext4_llseek(struct file *file, loff_t offset, int origin);
2373extern void ext4_unwritten_wait(struct inode *inode);
2374
2375/* namei.c */
2376extern const struct inode_operations ext4_dir_inode_operations;
2377extern const struct inode_operations ext4_special_inode_operations;
2378extern struct dentry *ext4_get_parent(struct dentry *child);
2379
2380/* symlink.c */
2381extern const struct inode_operations ext4_symlink_inode_operations;
2382extern const struct inode_operations ext4_fast_symlink_inode_operations;
2383
2384/* block_validity */
2385extern void ext4_release_system_zone(struct super_block *sb);
2386extern int ext4_setup_system_zone(struct super_block *sb);
2387extern int __init ext4_init_system_zone(void);
2388extern void ext4_exit_system_zone(void);
2389extern int ext4_data_block_valid(struct ext4_sb_info *sbi,
2390                                 ext4_fsblk_t start_blk,
2391                                 unsigned int count);
2392extern int ext4_check_blockref(const char *, unsigned int,
2393                               struct inode *, __le32 *, unsigned int);
2394
2395/* extents.c */
2396extern int ext4_ext_tree_init(handle_t *handle, struct inode *);
2397extern int ext4_ext_writepage_trans_blocks(struct inode *, int);
2398extern int ext4_ext_index_trans_blocks(struct inode *inode, int nrblocks,
2399                                       int chunk);
2400extern int ext4_ext_map_blocks(handle_t *handle, struct inode *inode,
2401                               struct ext4_map_blocks *map, int flags);
2402extern void ext4_ext_truncate(struct inode *);
2403extern int ext4_ext_punch_hole(struct file *file, loff_t offset,
2404                                loff_t length);
2405extern void ext4_ext_init(struct super_block *);
2406extern void ext4_ext_release(struct super_block *);
2407extern long ext4_fallocate(struct file *file, int mode, loff_t offset,
2408                          loff_t len);
2409extern int ext4_convert_unwritten_extents(struct inode *inode, loff_t offset,
2410                          ssize_t len);
2411extern int ext4_map_blocks(handle_t *handle, struct inode *inode,
2412                           struct ext4_map_blocks *map, int flags);
2413extern int ext4_fiemap(struct inode *inode, struct fiemap_extent_info *fieinfo,
2414                        __u64 start, __u64 len);
2415/* move_extent.c */
2416extern int ext4_move_extents(struct file *o_filp, struct file *d_filp,
2417                             __u64 start_orig, __u64 start_donor,
2418                             __u64 len, __u64 *moved_len);
2419
2420/* page-io.c */
2421extern int __init ext4_init_pageio(void);
2422extern void ext4_add_complete_io(ext4_io_end_t *io_end);
2423extern void ext4_exit_pageio(void);
2424extern void ext4_ioend_wait(struct inode *);
2425extern void ext4_free_io_end(ext4_io_end_t *io);
2426extern ext4_io_end_t *ext4_init_io_end(struct inode *inode, gfp_t flags);
2427extern void ext4_io_submit(struct ext4_io_submit *io);
2428extern int ext4_bio_write_page(struct ext4_io_submit *io,
2429                               struct page *page,
2430                               int len,
2431                               struct writeback_control *wbc);
2432
2433/* mmp.c */
2434extern int ext4_multi_mount_protect(struct super_block *, ext4_fsblk_t);
2435extern void ext4_mmp_csum_set(struct super_block *sb, struct mmp_struct *mmp);
2436extern int ext4_mmp_csum_verify(struct super_block *sb,
2437                                struct mmp_struct *mmp);
2438
2439/* BH_Uninit flag: blocks are allocated but uninitialized on disk */
2440enum ext4_state_bits {
2441        BH_Uninit       /* blocks are allocated but uninitialized on disk */
2442          = BH_JBDPrivateStart,
2443        BH_AllocFromCluster,    /* allocated blocks were part of already
2444                                 * allocated cluster. Note that this flag will
2445                                 * never, ever appear in a buffer_head's state
2446                                 * flag. See EXT4_MAP_FROM_CLUSTER to see where
2447                                 * this is used. */
2448        BH_Da_Mapped,   /* Delayed allocated block that now has a mapping. This
2449                         * flag is set when ext4_map_blocks is called on a
2450                         * delayed allocated block to get its real mapping. */
2451};
2452
2453BUFFER_FNS(Uninit, uninit)
2454TAS_BUFFER_FNS(Uninit, uninit)
2455BUFFER_FNS(Da_Mapped, da_mapped)
2456
2457/*
2458 * Add new method to test wether block and inode bitmaps are properly
2459 * initialized. With uninit_bg reading the block from disk is not enough
2460 * to mark the bitmap uptodate. We need to also zero-out the bitmap
2461 */
2462#define BH_BITMAP_UPTODATE BH_JBDPrivateStart
2463
2464static inline int bitmap_uptodate(struct buffer_head *bh)
2465{
2466        return (buffer_uptodate(bh) &&
2467                        test_bit(BH_BITMAP_UPTODATE, &(bh)->b_state));
2468}
2469static inline void set_bitmap_uptodate(struct buffer_head *bh)
2470{
2471        set_bit(BH_BITMAP_UPTODATE, &(bh)->b_state);
2472}
2473
2474/*
2475 * Disable DIO read nolock optimization, so new dioreaders will be forced
2476 * to grab i_mutex
2477 */
2478static inline void ext4_inode_block_unlocked_dio(struct inode *inode)
2479{
2480        ext4_set_inode_state(inode, EXT4_STATE_DIOREAD_LOCK);
2481        smp_mb();
2482}
2483static inline void ext4_inode_resume_unlocked_dio(struct inode *inode)
2484{
2485        smp_mb();
2486        ext4_clear_inode_state(inode, EXT4_STATE_DIOREAD_LOCK);
2487}
2488
2489#define in_range(b, first, len) ((b) >= (first) && (b) <= (first) + (len) - 1)
2490
2491/* For ioend & aio unwritten conversion wait queues */
2492#define EXT4_WQ_HASH_SZ         37
2493#define ext4_ioend_wq(v)   (&ext4__ioend_wq[((unsigned long)(v)) %\
2494                                            EXT4_WQ_HASH_SZ])
2495#define ext4_aio_mutex(v)  (&ext4__aio_mutex[((unsigned long)(v)) %\
2496                                             EXT4_WQ_HASH_SZ])
2497extern wait_queue_head_t ext4__ioend_wq[EXT4_WQ_HASH_SZ];
2498extern struct mutex ext4__aio_mutex[EXT4_WQ_HASH_SZ];
2499
2500#define EXT4_RESIZING   0
2501extern int ext4_resize_begin(struct super_block *sb);
2502extern void ext4_resize_end(struct super_block *sb);
2503
2504#endif  /* __KERNEL__ */
2505
2506#include "ext4_extents.h"
2507
2508#endif  /* _EXT4_H */
2509
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