fs/ext4/ext4.h

   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 /*
  61  * Turn on EXT_DEBUG to get lots of info about extents operations.
  62  */
  63 #define EXT_DEBUG__
  64 #ifdef EXT_DEBUG
  65 #define ext_debug(fmt, ...)     printk(fmt, ##__VA_ARGS__)
  66 #else
  67 #define ext_debug(fmt, ...)     no_printk(fmt, ##__VA_ARGS__)
  68 #endif
  69
  70 #define EXT4_ERROR_INODE(inode, fmt, a...) \
  71         ext4_error_inode((inode), __func__, __LINE__, 0, (fmt), ## a)
  72
  73 #define EXT4_ERROR_INODE_BLOCK(inode, block, fmt, a...)                 \
  74         ext4_error_inode((inode), __func__, __LINE__, (block), (fmt), ## a)
  75
  76 #define EXT4_ERROR_FILE(file, block, fmt, a...)                         \
  77         ext4_error_file((file), __func__, __LINE__, (block), (fmt), ## a)
  78
  79 /* data type for block offset of block group */
  80 typedef int ext4_grpblk_t;
  81
  82 /* data type for filesystem-wide blocks number */
  83 typedef unsigned long long ext4_fsblk_t;
  84
  85 /* data type for file logical block number */
  86 typedef __u32 ext4_lblk_t;
  87
  88 /* data type for block group number */
  89 typedef unsigned int ext4_group_t;
  90
  91 /*
  92  * Flags used in mballoc's allocation_context flags field.
  93  *
  94  * Also used to show what's going on for debugging purposes when the
  95  * flag field is exported via the traceport interface
  96  */
  97
  98 /* prefer goal again. length */
  99 #define EXT4_MB_HINT_MERGE              0x0001
 100 /* blocks already reserved */
 101 #define EXT4_MB_HINT_RESERVED           0x0002
 102 /* metadata is being allocated */
 103 #define EXT4_MB_HINT_METADATA           0x0004
 104 /* first blocks in the file */
 105 #define EXT4_MB_HINT_FIRST              0x0008
 106 /* search for the best chunk */
 107 #define EXT4_MB_HINT_BEST               0x0010
 108 /* data is being allocated */
 109 #define EXT4_MB_HINT_DATA               0x0020
 110 /* don't preallocate (for tails) */
 111 #define EXT4_MB_HINT_NOPREALLOC         0x0040
 112 /* allocate for locality group */
 113 #define EXT4_MB_HINT_GROUP_ALLOC        0x0080
 114 /* allocate goal blocks or none */
 115 #define EXT4_MB_HINT_GOAL_ONLY          0x0100
 116 /* goal is meaningful */
 117 #define EXT4_MB_HINT_TRY_GOAL           0x0200
 118 /* blocks already pre-reserved by delayed allocation */
 119 #define EXT4_MB_DELALLOC_RESERVED       0x0400
 120 /* We are doing stream allocation */
 121 #define EXT4_MB_STREAM_ALLOC            0x0800
 122 /* Use reserved root blocks if needed */
 123 #define EXT4_MB_USE_ROOT_BLOCKS         0x1000
 124
 125 struct ext4_allocation_request {
 126         /* target inode for block we're allocating */
 127         struct inode *inode;
 128         /* how many blocks we want to allocate */
 129         unsigned int len;
 130         /* logical block in target inode */
 131         ext4_lblk_t logical;
 132         /* the closest logical allocated block to the left */
 133         ext4_lblk_t lleft;
 134         /* the closest logical allocated block to the right */
 135         ext4_lblk_t lright;
 136         /* phys. target (a hint) */
 137         ext4_fsblk_t goal;
 138         /* phys. block for the closest logical allocated block to the left */
 139         ext4_fsblk_t pleft;
 140         /* phys. block for the closest logical allocated block to the right */
 141         ext4_fsblk_t pright;
 142         /* flags. see above EXT4_MB_HINT_* */
 143         unsigned int flags;
 144 };
 145
 146 /*
 147  * Logical to physical block mapping, used by ext4_map_blocks()
 148  *
 149  * This structure is used to pass requests into ext4_map_blocks() as
 150  * well as to store the information returned by ext4_map_blocks().  It
 151  * takes less room on the stack than a struct buffer_head.
 152  */
 153 #define EXT4_MAP_NEW            (1 << BH_New)
 154 #define EXT4_MAP_MAPPED         (1 << BH_Mapped)
 155 #define EXT4_MAP_UNWRITTEN      (1 << BH_Unwritten)
 156 #define EXT4_MAP_BOUNDARY       (1 << BH_Boundary)
 157 #define EXT4_MAP_UNINIT         (1 << BH_Uninit)
 158 /* Sometimes (in the bigalloc case, from ext4_da_get_block_prep) the caller of
 159  * ext4_map_blocks wants to know whether or not the underlying cluster has
 160  * already been accounted for. EXT4_MAP_FROM_CLUSTER conveys to the caller that
 161  * the requested mapping was from previously mapped (or delayed allocated)
 162  * cluster. We use BH_AllocFromCluster only for this flag. BH_AllocFromCluster
 163  * should never appear on buffer_head's state flags.
 164  */
 165 #define EXT4_MAP_FROM_CLUSTER   (1 << BH_AllocFromCluster)
 166 #define EXT4_MAP_FLAGS          (EXT4_MAP_NEW | EXT4_MAP_MAPPED |\
 167                                  EXT4_MAP_UNWRITTEN | EXT4_MAP_BOUNDARY |\
 168                                  EXT4_MAP_UNINIT | EXT4_MAP_FROM_CLUSTER)
 169
 170 struct ext4_map_blocks {
 171         ext4_fsblk_t m_pblk;
 172         ext4_lblk_t m_lblk;
 173         unsigned int m_len;
 174         unsigned int m_flags;
 175 };
 176
 177 /*
 178  * For delayed allocation tracking
 179  */
 180 struct mpage_da_data {
 181         struct inode *inode;
 182         sector_t b_blocknr;             /* start block number of extent */
 183         size_t b_size;                  /* size of extent */
 184         unsigned long b_state;          /* state of the extent */
 185         unsigned long first_page, next_page;    /* extent of pages */
 186         struct writeback_control *wbc;
 187         int io_done;
 188         int pages_written;
 189         int retval;
 190 };
 191
 192 /*
 193  * Flags for ext4_io_end->flags
 194  */
 195 #define EXT4_IO_END_UNWRITTEN   0x0001
 196 #define EXT4_IO_END_ERROR       0x0002
 197 #define EXT4_IO_END_DIRECT      0x0004
 198
 199 struct ext4_io_page {
 200         struct page     *p_page;
 201         atomic_t        p_count;
 202 };
 203
 204 #define MAX_IO_PAGES 128
 205
 206 /*
 207  * For converting uninitialized extents on a work queue.
 208  *
 209  * 'page' is only used from the writepage() path; 'pages' is only used for
 210  * buffered writes; they are used to keep page references until conversion
 211  * takes place.  For AIO/DIO, neither field is filled in.
 212  */
 213 typedef struct ext4_io_end {
 214         struct list_head        list;           /* per-file finished IO list */
 215         struct inode            *inode;         /* file being written to */
 216         unsigned int            flag;           /* unwritten or not */
 217         loff_t                  offset;         /* offset in the file */
 218         ssize_t                 size;           /* size of the extent */
 219         struct kiocb            *iocb;          /* iocb struct for AIO */
 220         int                     result;         /* error value for AIO */
 221         int                     num_io_pages;   /* for writepages() */
 222         struct ext4_io_page     *pages[MAX_IO_PAGES]; /* for writepages() */
 223 } ext4_io_end_t;
 224
 225 struct ext4_io_submit {
 226         int                     io_op;
 227         struct bio              *io_bio;
 228         ext4_io_end_t           *io_end;
 229         struct ext4_io_page     *io_page;
 230         sector_t                io_next_block;
 231 };
 232
 233 /*
 234  * Special inodes numbers
 235  */
 236 #define EXT4_BAD_INO             1      /* Bad blocks inode */
 237 #define EXT4_ROOT_INO            2      /* Root inode */
 238 #define EXT4_USR_QUOTA_INO       3      /* User quota inode */
 239 #define EXT4_GRP_QUOTA_INO       4      /* Group quota inode */
 240 #define EXT4_BOOT_LOADER_INO     5      /* Boot loader inode */
 241 #define EXT4_UNDEL_DIR_INO       6      /* Undelete directory inode */
 242 #define EXT4_RESIZE_INO          7      /* Reserved group descriptors inode */
 243 #define EXT4_JOURNAL_INO         8      /* Journal inode */
 244
 245 /* First non-reserved inode for old ext4 filesystems */
 246 #define EXT4_GOOD_OLD_FIRST_INO 11
 247
 248 /*
 249  * Maximal count of links to a file
 250  */
 251 #define EXT4_LINK_MAX           65000
 252
 253 /*
 254  * Macro-instructions used to manage several block sizes
 255  */
 256 #define EXT4_MIN_BLOCK_SIZE             1024
 257 #define EXT4_MAX_BLOCK_SIZE             65536
 258 #define EXT4_MIN_BLOCK_LOG_SIZE         10
 259 #define EXT4_MAX_BLOCK_LOG_SIZE         16
 260 #ifdef __KERNEL__
 261 # define EXT4_BLOCK_SIZE(s)             ((s)->s_blocksize)
 262 #else
 263 # define EXT4_BLOCK_SIZE(s)             (EXT4_MIN_BLOCK_SIZE << (s)->s_log_block_size)
 264 #endif
 265 #define EXT4_ADDR_PER_BLOCK(s)          (EXT4_BLOCK_SIZE(s) / sizeof(__u32))
 266 #define EXT4_CLUSTER_SIZE(s)            (EXT4_BLOCK_SIZE(s) << \
 267                                          EXT4_SB(s)->s_cluster_bits)
 268 #ifdef __KERNEL__
 269 # define EXT4_BLOCK_SIZE_BITS(s)        ((s)->s_blocksize_bits)
 270 # define EXT4_CLUSTER_BITS(s)           (EXT4_SB(s)->s_cluster_bits)
 271 #else
 272 # define EXT4_BLOCK_SIZE_BITS(s)        ((s)->s_log_block_size + 10)
 273 #endif
 274 #ifdef __KERNEL__
 275 #define EXT4_ADDR_PER_BLOCK_BITS(s)     (EXT4_SB(s)->s_addr_per_block_bits)
 276 #define EXT4_INODE_SIZE(s)              (EXT4_SB(s)->s_inode_size)
 277 #define EXT4_FIRST_INO(s)               (EXT4_SB(s)->s_first_ino)
 278 #else
 279 #define EXT4_INODE_SIZE(s)      (((s)->s_rev_level == EXT4_GOOD_OLD_REV) ? \
 280                                  EXT4_GOOD_OLD_INODE_SIZE : \
 281                                  (s)->s_inode_size)
 282 #define EXT4_FIRST_INO(s)       (((s)->s_rev_level == EXT4_GOOD_OLD_REV) ? \
 283                                  EXT4_GOOD_OLD_FIRST_INO : \
 284                                  (s)->s_first_ino)
 285 #endif
 286 #define EXT4_BLOCK_ALIGN(size, blkbits)         ALIGN((size), (1 << (blkbits)))
 287
 288 /* Translate a block number to a cluster number */
 289 #define EXT4_B2C(sbi, blk)      ((blk) >> (sbi)->s_cluster_bits)
 290 /* Translate a cluster number to a block number */
 291 #define EXT4_C2B(sbi, cluster)  ((cluster) << (sbi)->s_cluster_bits)
 292 /* Translate # of blks to # of clusters */
 293 #define EXT4_NUM_B2C(sbi, blks) (((blks) + (sbi)->s_cluster_ratio - 1) >> \
 294                                  (sbi)->s_cluster_bits)
 295
 296 /*
 297  * Structure of a blocks group descriptor
 298  */
 299 struct ext4_group_desc
 300 {
 301         __le32  bg_block_bitmap_lo;     /* Blocks bitmap block */
 302         __le32  bg_inode_bitmap_lo;     /* Inodes bitmap block */
 303         __le32  bg_inode_table_lo;      /* Inodes table block */
 304         __le16  bg_free_blocks_count_lo;/* Free blocks count */
 305         __le16  bg_free_inodes_count_lo;/* Free inodes count */
 306         __le16  bg_used_dirs_count_lo;  /* Directories count */
 307         __le16  bg_flags;               /* EXT4_BG_flags (INODE_UNINIT, etc) */
 308         __le32  bg_exclude_bitmap_lo;   /* Exclude bitmap for snapshots */
 309         __le16  bg_block_bitmap_csum_lo;/* crc32c(s_uuid+grp_num+bbitmap) LE */
 310         __le16  bg_inode_bitmap_csum_lo;/* crc32c(s_uuid+grp_num+ibitmap) LE */
 311         __le16  bg_itable_unused_lo;    /* Unused inodes count */
 312         __le16  bg_checksum;            /* crc16(sb_uuid+group+desc) */
 313         __le32  bg_block_bitmap_hi;     /* Blocks bitmap block MSB */
 314         __le32  bg_inode_bitmap_hi;     /* Inodes bitmap block MSB */
 315         __le32  bg_inode_table_hi;      /* Inodes table block MSB */
 316         __le16  bg_free_blocks_count_hi;/* Free blocks count MSB */
 317         __le16  bg_free_inodes_count_hi;/* Free inodes count MSB */
 318         __le16  bg_used_dirs_count_hi;  /* Directories count MSB */
 319         __le16  bg_itable_unused_hi;    /* Unused inodes count MSB */
 320         __le32  bg_exclude_bitmap_hi;   /* Exclude bitmap block MSB */
 321         __le16  bg_block_bitmap_csum_hi;/* crc32c(s_uuid+grp_num+bbitmap) BE */
 322         __le16  bg_inode_bitmap_csum_hi;/* crc32c(s_uuid+grp_num+ibitmap) BE */
 323         __u32   bg_reserved;
 324 };
 325
 326 #define EXT4_BG_INODE_BITMAP_CSUM_HI_END        \
 327         (offsetof(struct ext4_group_desc, bg_inode_bitmap_csum_hi) + \
 328          sizeof(__le16))
 329 #define EXT4_BG_BLOCK_BITMAP_CSUM_HI_END        \
 330         (offsetof(struct ext4_group_desc, bg_block_bitmap_csum_hi) + \
 331          sizeof(__le16))
 332
 333 /*
 334  * Structure of a flex block group info
 335  */
 336
 337 struct flex_groups {
 338         atomic_t free_inodes;
 339         atomic_t free_clusters;
 340         atomic_t used_dirs;
 341 };
 342
 343 #define EXT4_BG_INODE_UNINIT    0x0001 /* Inode table/bitmap not in use */
 344 #define EXT4_BG_BLOCK_UNINIT    0x0002 /* Block bitmap not in use */
 345 #define EXT4_BG_INODE_ZEROED    0x0004 /* On-disk itable initialized to zero */
 346
 347 /*
 348  * Macro-instructions used to manage group descriptors
 349  */
 350 #define EXT4_MIN_DESC_SIZE              32
 351 #define EXT4_MIN_DESC_SIZE_64BIT        64
 352 #define EXT4_MAX_DESC_SIZE              EXT4_MIN_BLOCK_SIZE
 353 #define EXT4_DESC_SIZE(s)               (EXT4_SB(s)->s_desc_size)
 354 #ifdef __KERNEL__
 355 # define EXT4_BLOCKS_PER_GROUP(s)       (EXT4_SB(s)->s_blocks_per_group)
 356 # define EXT4_CLUSTERS_PER_GROUP(s)     (EXT4_SB(s)->s_clusters_per_group)
 357 # define EXT4_DESC_PER_BLOCK(s)         (EXT4_SB(s)->s_desc_per_block)
 358 # define EXT4_INODES_PER_GROUP(s)       (EXT4_SB(s)->s_inodes_per_group)
 359 # define EXT4_DESC_PER_BLOCK_BITS(s)    (EXT4_SB(s)->s_desc_per_block_bits)
 360 #else
 361 # define EXT4_BLOCKS_PER_GROUP(s)       ((s)->s_blocks_per_group)
 362 # define EXT4_DESC_PER_BLOCK(s)         (EXT4_BLOCK_SIZE(s) / EXT4_DESC_SIZE(s))
 363 # define EXT4_INODES_PER_GROUP(s)       ((s)->s_inodes_per_group)
 364 #endif
 365
 366 /*
 367  * Constants relative to the data blocks
 368  */
 369 #define EXT4_NDIR_BLOCKS                12
 370 #define EXT4_IND_BLOCK                  EXT4_NDIR_BLOCKS
 371 #define EXT4_DIND_BLOCK                 (EXT4_IND_BLOCK + 1)
 372 #define EXT4_TIND_BLOCK                 (EXT4_DIND_BLOCK + 1)
 373 #define EXT4_N_BLOCKS                   (EXT4_TIND_BLOCK + 1)
 374
 375 /*
 376  * Inode flags
 377  */
 378 #define EXT4_SECRM_FL                   0x00000001 /* Secure deletion */
 379 #define EXT4_UNRM_FL                    0x00000002 /* Undelete */
 380 #define EXT4_COMPR_FL                   0x00000004 /* Compress file */
 381 #define EXT4_SYNC_FL                    0x00000008 /* Synchronous updates */
 382 #define EXT4_IMMUTABLE_FL               0x00000010 /* Immutable file */
 383 #define EXT4_APPEND_FL                  0x00000020 /* writes to file may only append */
 384 #define EXT4_NODUMP_FL                  0x00000040 /* do not dump file */
 385 #define EXT4_NOATIME_FL                 0x00000080 /* do not update atime */
 386 /* Reserved for compression usage... */
 387 #define EXT4_DIRTY_FL                   0x00000100
 388 #define EXT4_COMPRBLK_FL                0x00000200 /* One or more compressed clusters */
 389 #define EXT4_NOCOMPR_FL                 0x00000400 /* Don't compress */
 390 #define EXT4_ECOMPR_FL                  0x00000800 /* Compression error */
 391 /* End compression flags --- maybe not all used */
 392 #define EXT4_INDEX_FL                   0x00001000 /* hash-indexed directory */
 393 #define EXT4_IMAGIC_FL                  0x00002000 /* AFS directory */
 394 #define EXT4_JOURNAL_DATA_FL            0x00004000 /* file data should be journaled */
 395 #define EXT4_NOTAIL_FL                  0x00008000 /* file tail should not be merged */
 396 #define EXT4_DIRSYNC_FL                 0x00010000 /* dirsync behaviour (directories only) */
 397 #define EXT4_TOPDIR_FL                  0x00020000 /* Top of directory hierarchies*/
 398 #define EXT4_HUGE_FILE_FL               0x00040000 /* Set to each huge file */
 399 #define EXT4_EXTENTS_FL                 0x00080000 /* Inode uses extents */
 400 #define EXT4_EA_INODE_FL                0x00200000 /* Inode used for large EA */
 401 #define EXT4_EOFBLOCKS_FL               0x00400000 /* Blocks allocated beyond EOF */
 402 #define EXT4_INLINE_DATA_FL             0x10000000 /* Inode has inline data. */
 403 #define EXT4_RESERVED_FL                0x80000000 /* reserved for ext4 lib */
 404
 405 #define EXT4_FL_USER_VISIBLE            0x004BDFFF /* User visible flags */
 406 #define EXT4_FL_USER_MODIFIABLE         0x004B80FF /* User modifiable flags */
 407
 408 /* Flags that should be inherited by new inodes from their parent. */
 409 #define EXT4_FL_INHERITED (EXT4_SECRM_FL | EXT4_UNRM_FL | EXT4_COMPR_FL |\
 410                            EXT4_SYNC_FL | EXT4_NODUMP_FL | EXT4_NOATIME_FL |\
 411                            EXT4_NOCOMPR_FL | EXT4_JOURNAL_DATA_FL |\
 412                            EXT4_NOTAIL_FL | EXT4_DIRSYNC_FL)
 413
 414 /* Flags that are appropriate for regular files (all but dir-specific ones). */
 415 #define EXT4_REG_FLMASK (~(EXT4_DIRSYNC_FL | EXT4_TOPDIR_FL))
 416
 417 /* Flags that are appropriate for non-directories/regular files. */
 418 #define EXT4_OTHER_FLMASK (EXT4_NODUMP_FL | EXT4_NOATIME_FL)
 419
 420 /* Mask out flags that are inappropriate for the given type of inode. */
 421 static inline __u32 ext4_mask_flags(umode_t mode, __u32 flags)
 422 {
 423         if (S_ISDIR(mode))
 424                 return flags;
 425         else if (S_ISREG(mode))
 426                 return flags & EXT4_REG_FLMASK;
 427         else
 428                 return flags & EXT4_OTHER_FLMASK;
 429 }
 430
 431 /*
 432  * Inode flags used for atomic set/get
 433  */
 434 enum {
 435         EXT4_INODE_SECRM        = 0,    /* Secure deletion */
 436         EXT4_INODE_UNRM         = 1,    /* Undelete */
 437         EXT4_INODE_COMPR        = 2,    /* Compress file */
 438         EXT4_INODE_SYNC         = 3,    /* Synchronous updates */
 439         EXT4_INODE_IMMUTABLE    = 4,    /* Immutable file */
 440         EXT4_INODE_APPEND       = 5,    /* writes to file may only append */
 441         EXT4_INODE_NODUMP       = 6,    /* do not dump file */
 442         EXT4_INODE_NOATIME      = 7,    /* do not update atime */
 443 /* Reserved for compression usage... */
 444         EXT4_INODE_DIRTY        = 8,
 445         EXT4_INODE_COMPRBLK     = 9,    /* One or more compressed clusters */
 446         EXT4_INODE_NOCOMPR      = 10,   /* Don't compress */
 447         EXT4_INODE_ECOMPR       = 11,   /* Compression error */
 448 /* End compression flags --- maybe not all used */
 449         EXT4_INODE_INDEX        = 12,   /* hash-indexed directory */
 450         EXT4_INODE_IMAGIC       = 13,   /* AFS directory */
 451         EXT4_INODE_JOURNAL_DATA = 14,   /* file data should be journaled */
 452         EXT4_INODE_NOTAIL       = 15,   /* file tail should not be merged */
 453         EXT4_INODE_DIRSYNC      = 16,   /* dirsync behaviour (directories only) */
 454         EXT4_INODE_TOPDIR       = 17,   /* Top of directory hierarchies*/
 455         EXT4_INODE_HUGE_FILE    = 18,   /* Set to each huge file */
 456         EXT4_INODE_EXTENTS      = 19,   /* Inode uses extents */
 457         EXT4_INODE_EA_INODE     = 21,   /* Inode used for large EA */
 458         EXT4_INODE_EOFBLOCKS    = 22,   /* Blocks allocated beyond EOF */
 459         EXT4_INODE_INLINE_DATA  = 28,   /* Data in inode. */
 460         EXT4_INODE_RESERVED     = 31,   /* reserved for ext4 lib */
 461 };
 462
 463 /*
 464  * Since it's pretty easy to mix up bit numbers and hex values, we use a
 465  * build-time check to make sure that EXT4_XXX_FL is consistent with respect to
 466  * EXT4_INODE_XXX. If all is well, the macros will be dropped, so, it won't cost
 467  * any extra space in the compiled kernel image, otherwise, the build will fail.
 468  * It's important that these values are the same, since we are using
 469  * EXT4_INODE_XXX to test for flag values, but EXT4_XXX_FL must be consistent
 470  * with the values of FS_XXX_FL defined in include/linux/fs.h and the on-disk
 471  * values found in ext2, ext3 and ext4 filesystems, and of course the values
 472  * defined in e2fsprogs.
 473  *
 474  * It's not paranoia if the Murphy's Law really *is* out to get you.  :-)
 475  */
 476 #define TEST_FLAG_VALUE(FLAG) (EXT4_##FLAG##_FL == (1 << EXT4_INODE_##FLAG))
 477 #define CHECK_FLAG_VALUE(FLAG) BUILD_BUG_ON(!TEST_FLAG_VALUE(FLAG))
 478
 479 static inline void ext4_check_flag_values(void)
 480 {
 481         CHECK_FLAG_VALUE(SECRM);
 482         CHECK_FLAG_VALUE(UNRM);
 483         CHECK_FLAG_VALUE(COMPR);
 484         CHECK_FLAG_VALUE(SYNC);
 485         CHECK_FLAG_VALUE(IMMUTABLE);
 486         CHECK_FLAG_VALUE(APPEND);
 487         CHECK_FLAG_VALUE(NODUMP);
 488         CHECK_FLAG_VALUE(NOATIME);
 489         CHECK_FLAG_VALUE(DIRTY);
 490         CHECK_FLAG_VALUE(COMPRBLK);
 491         CHECK_FLAG_VALUE(NOCOMPR);
 492         CHECK_FLAG_VALUE(ECOMPR);
 493         CHECK_FLAG_VALUE(INDEX);
 494         CHECK_FLAG_VALUE(IMAGIC);
 495         CHECK_FLAG_VALUE(JOURNAL_DATA);
 496         CHECK_FLAG_VALUE(NOTAIL);
 497         CHECK_FLAG_VALUE(DIRSYNC);
 498         CHECK_FLAG_VALUE(TOPDIR);
 499         CHECK_FLAG_VALUE(HUGE_FILE);
 500         CHECK_FLAG_VALUE(EXTENTS);
 501         CHECK_FLAG_VALUE(EA_INODE);
 502         CHECK_FLAG_VALUE(EOFBLOCKS);
 503         CHECK_FLAG_VALUE(INLINE_DATA);
 504         CHECK_FLAG_VALUE(RESERVED);
 505 }
 506
 507 /* Used to pass group descriptor data when online resize is done */
 508 struct ext4_new_group_input {
 509         __u32 group;            /* Group number for this data */
 510         __u64 block_bitmap;     /* Absolute block number of block bitmap */
 511         __u64 inode_bitmap;     /* Absolute block number of inode bitmap */
 512         __u64 inode_table;      /* Absolute block number of inode table start */
 513         __u32 blocks_count;     /* Total number of blocks in this group */
 514         __u16 reserved_blocks;  /* Number of reserved blocks in this group */
 515         __u16 unused;
 516 };
 517
 518 #if defined(__KERNEL__) && defined(CONFIG_COMPAT)
 519 struct compat_ext4_new_group_input {
 520         u32 group;
 521         compat_u64 block_bitmap;
 522         compat_u64 inode_bitmap;
 523         compat_u64 inode_table;
 524         u32 blocks_count;
 525         u16 reserved_blocks;
 526         u16 unused;
 527 };
 528 #endif
 529
 530 /* The struct ext4_new_group_input in kernel space, with free_blocks_count */
 531 struct ext4_new_group_data {
 532         __u32 group;
 533         __u64 block_bitmap;
 534         __u64 inode_bitmap;
 535         __u64 inode_table;
 536         __u32 blocks_count;
 537         __u16 reserved_blocks;
 538         __u16 unused;
 539         __u32 free_blocks_count;
 540 };
 541
 542 /* Indexes used to index group tables in ext4_new_group_data */
 543 enum {
 544         BLOCK_BITMAP = 0,       /* block bitmap */
 545         INODE_BITMAP,           /* inode bitmap */
 546         INODE_TABLE,            /* inode tables */
 547         GROUP_TABLE_COUNT,
 548 };
 549
 550 /*
 551  * Flags used by ext4_map_blocks()
 552  */
 553         /* Allocate any needed blocks and/or convert an unitialized
 554            extent to be an initialized ext4 */
 555 #define EXT4_GET_BLOCKS_CREATE                  0x0001
 556         /* Request the creation of an unitialized extent */
 557 #define EXT4_GET_BLOCKS_UNINIT_EXT              0x0002
 558 #define EXT4_GET_BLOCKS_CREATE_UNINIT_EXT       (EXT4_GET_BLOCKS_UNINIT_EXT|\
 559                                                  EXT4_GET_BLOCKS_CREATE)
 560         /* Caller is from the delayed allocation writeout path,
 561            so set the magic i_delalloc_reserve_flag after taking the
 562            inode allocation semaphore for */
 563 #define EXT4_GET_BLOCKS_DELALLOC_RESERVE        0x0004
 564         /* caller is from the direct IO path, request to creation of an
 565         unitialized extents if not allocated, split the uninitialized
 566         extent if blocks has been preallocated already*/
 567 #define EXT4_GET_BLOCKS_PRE_IO                  0x0008
 568 #define EXT4_GET_BLOCKS_CONVERT                 0x0010
 569 #define EXT4_GET_BLOCKS_IO_CREATE_EXT           (EXT4_GET_BLOCKS_PRE_IO|\
 570                                          EXT4_GET_BLOCKS_CREATE_UNINIT_EXT)
 571         /* Convert extent to initialized after IO complete */
 572 #define EXT4_GET_BLOCKS_IO_CONVERT_EXT          (EXT4_GET_BLOCKS_CONVERT|\
 573                                          EXT4_GET_BLOCKS_CREATE_UNINIT_EXT)
 574         /* Punch out blocks of an extent */
 575 #define EXT4_GET_BLOCKS_PUNCH_OUT_EXT           0x0020
 576         /* Don't normalize allocation size (used for fallocate) */
 577 #define EXT4_GET_BLOCKS_NO_NORMALIZE            0x0040
 578         /* Request will not result in inode size update (user for fallocate) */
 579 #define EXT4_GET_BLOCKS_KEEP_SIZE               0x0080
 580         /* Do not take i_data_sem locking in ext4_map_blocks */
 581 #define EXT4_GET_BLOCKS_NO_LOCK                 0x0100
 582         /* Do not put hole in extent cache */
 583 #define EXT4_GET_BLOCKS_NO_PUT_HOLE             0x0200
 584
 585 /*
 586  * Flags used by ext4_free_blocks
 587  */
 588 #define EXT4_FREE_BLOCKS_METADATA       0x0001
 589 #define EXT4_FREE_BLOCKS_FORGET         0x0002
 590 #define EXT4_FREE_BLOCKS_VALIDATED      0x0004
 591 #define EXT4_FREE_BLOCKS_NO_QUOT_UPDATE 0x0008
 592 #define EXT4_FREE_BLOCKS_NOFREE_FIRST_CLUSTER   0x0010
 593 #define EXT4_FREE_BLOCKS_NOFREE_LAST_CLUSTER    0x0020
 594
 595 /*
 596  * Flags used by ext4_discard_partial_page_buffers
 597  */
 598 #define EXT4_DISCARD_PARTIAL_PG_ZERO_UNMAPPED   0x0001
 599
 600 /*
 601  * ioctl commands
 602  */
 603 #define EXT4_IOC_GETFLAGS               FS_IOC_GETFLAGS
 604 #define EXT4_IOC_SETFLAGS               FS_IOC_SETFLAGS
 605 #define EXT4_IOC_GETVERSION             _IOR('f', 3, long)
 606 #define EXT4_IOC_SETVERSION             _IOW('f', 4, long)
 607 #define EXT4_IOC_GETVERSION_OLD         FS_IOC_GETVERSION
 608 #define EXT4_IOC_SETVERSION_OLD         FS_IOC_SETVERSION
 609 #define EXT4_IOC_GETRSVSZ               _IOR('f', 5, long)
 610 #define EXT4_IOC_SETRSVSZ               _IOW('f', 6, long)
 611 #define EXT4_IOC_GROUP_EXTEND           _IOW('f', 7, unsigned long)
 612 #define EXT4_IOC_GROUP_ADD              _IOW('f', 8, struct ext4_new_group_input)
 613 #define EXT4_IOC_MIGRATE                _IO('f', 9)
 614  /* note ioctl 10 reserved for an early version of the FIEMAP ioctl */
 615  /* note ioctl 11 reserved for filesystem-independent FIEMAP ioctl */
 616 #define EXT4_IOC_ALLOC_DA_BLKS          _IO('f', 12)
 617 #define EXT4_IOC_MOVE_EXT               _IOWR('f', 15, struct move_extent)
 618 #define EXT4_IOC_RESIZE_FS              _IOW('f', 16, __u64)
 619
 620 #if defined(__KERNEL__) && defined(CONFIG_COMPAT)
 621 /*
 622  * ioctl commands in 32 bit emulation
 623  */
 624 #define EXT4_IOC32_GETFLAGS             FS_IOC32_GETFLAGS
 625 #define EXT4_IOC32_SETFLAGS             FS_IOC32_SETFLAGS
 626 #define EXT4_IOC32_GETVERSION           _IOR('f', 3, int)
 627 #define EXT4_IOC32_SETVERSION           _IOW('f', 4, int)
 628 #define EXT4_IOC32_GETRSVSZ             _IOR('f', 5, int)
 629 #define EXT4_IOC32_SETRSVSZ             _IOW('f', 6, int)
 630 #define EXT4_IOC32_GROUP_EXTEND         _IOW('f', 7, unsigned int)
 631 #define EXT4_IOC32_GROUP_ADD            _IOW('f', 8, struct compat_ext4_new_group_input)
 632 #define EXT4_IOC32_GETVERSION_OLD       FS_IOC32_GETVERSION
 633 #define EXT4_IOC32_SETVERSION_OLD       FS_IOC32_SETVERSION
 634 #endif
 635
 636 /* Max physical block we can address w/o extents */
 637 #define EXT4_MAX_BLOCK_FILE_PHYS        0xFFFFFFFF
 638
 639 /*
 640  * Structure of an inode on the disk
 641  */
 642 struct ext4_inode {
 643         __le16  i_mode;         /* File mode */
 644         __le16  i_uid;          /* Low 16 bits of Owner Uid */
 645         __le32  i_size_lo;      /* Size in bytes */
 646         __le32  i_atime;        /* Access time */
 647         __le32  i_ctime;        /* Inode Change time */
 648         __le32  i_mtime;        /* Modification time */
 649         __le32  i_dtime;        /* Deletion Time */
 650         __le16  i_gid;          /* Low 16 bits of Group Id */
 651         __le16  i_links_count;  /* Links count */
 652         __le32  i_blocks_lo;    /* Blocks count */
 653         __le32  i_flags;        /* File flags */
 654         union {
 655                 struct {
 656                         __le32  l_i_version;
 657                 } linux1;
 658                 struct {
 659                         __u32  h_i_translator;
 660                 } hurd1;
 661                 struct {
 662                         __u32  m_i_reserved1;
 663                 } masix1;
 664         } osd1;                         /* OS dependent 1 */
 665         __le32  i_block[EXT4_N_BLOCKS];/* Pointers to blocks */
 666         __le32  i_generation;   /* File version (for NFS) */
 667         __le32  i_file_acl_lo;  /* File ACL */
 668         __le32  i_size_high;
 669         __le32  i_obso_faddr;   /* Obsoleted fragment address */
 670         union {
 671                 struct {
 672                         __le16  l_i_blocks_high; /* were l_i_reserved1 */
 673                         __le16  l_i_file_acl_high;
 674                         __le16  l_i_uid_high;   /* these 2 fields */
 675                         __le16  l_i_gid_high;   /* were reserved2[0] */
 676                         __le16  l_i_checksum_lo;/* crc32c(uuid+inum+inode) LE */
 677                         __le16  l_i_reserved;
 678                 } linux2;
 679                 struct {
 680                         __le16  h_i_reserved1;  /* Obsoleted fragment number/size which are removed in ext4 */
 681                         __u16   h_i_mode_high;
 682                         __u16   h_i_uid_high;
 683                         __u16   h_i_gid_high;
 684                         __u32   h_i_author;
 685                 } hurd2;
 686                 struct {
 687                         __le16  h_i_reserved1;  /* Obsoleted fragment number/size which are removed in ext4 */
 688                         __le16  m_i_file_acl_high;
 689                         __u32   m_i_reserved2[2];
 690                 } masix2;
 691         } osd2;                         /* OS dependent 2 */
 692         __le16  i_extra_isize;
 693         __le16  i_checksum_hi;  /* crc32c(uuid+inum+inode) BE */
 694         __le32  i_ctime_extra;  /* extra Change time      (nsec << 2 | epoch) */
 695         __le32  i_mtime_extra;  /* extra Modification time(nsec << 2 | epoch) */
 696         __le32  i_atime_extra;  /* extra Access time      (nsec << 2 | epoch) */
 697         __le32  i_crtime;       /* File Creation time */
 698         __le32  i_crtime_extra; /* extra FileCreationtime (nsec << 2 | epoch) */
 699         __le32  i_version_hi;   /* high 32 bits for 64-bit version */
 700 };
 701
 702 struct move_extent {
 703         __u32 reserved;         /* should be zero */
 704         __u32 donor_fd;         /* donor file descriptor */
 705         __u64 orig_start;       /* logical start offset in block for orig */
 706         __u64 donor_start;      /* logical start offset in block for donor */
 707         __u64 len;              /* block length to be moved */
 708         __u64 moved_len;        /* moved block length */
 709 };
 710
 711 #define EXT4_EPOCH_BITS 2
 712 #define EXT4_EPOCH_MASK ((1 << EXT4_EPOCH_BITS) - 1)
 713 #define EXT4_NSEC_MASK  (~0UL << EXT4_EPOCH_BITS)
 714
 715 /*
 716  * Extended fields will fit into an inode if the filesystem was formatted
 717  * with large inodes (-I 256 or larger) and there are not currently any EAs
 718  * consuming all of the available space. For new inodes we always reserve
 719  * enough space for the kernel's known extended fields, but for inodes
 720  * created with an old kernel this might not have been the case. None of
 721  * the extended inode fields is critical for correct filesystem operation.
 722  * This macro checks if a certain field fits in the inode. Note that
 723  * inode-size = GOOD_OLD_INODE_SIZE + i_extra_isize
 724  */
 725 #define EXT4_FITS_IN_INODE(ext4_inode, einode, field)   \
 726         ((offsetof(typeof(*ext4_inode), field) +        \
 727           sizeof((ext4_inode)->field))                  \
 728         <= (EXT4_GOOD_OLD_INODE_SIZE +                  \
 729             (einode)->i_extra_isize))                   \
 730
 731 static inline __le32 ext4_encode_extra_time(struct timespec *time)
 732 {
 733        return cpu_to_le32((sizeof(time->tv_sec) > 4 ?
 734                            (time->tv_sec >> 32) & EXT4_EPOCH_MASK : 0) |
 735                           ((time->tv_nsec << EXT4_EPOCH_BITS) & EXT4_NSEC_MASK));
 736 }
 737
 738 static inline void ext4_decode_extra_time(struct timespec *time, __le32 extra)
 739 {
 740        if (sizeof(time->tv_sec) > 4)
 741                time->tv_sec |= (__u64)(le32_to_cpu(extra) & EXT4_EPOCH_MASK)
 742                                << 32;
 743        time->tv_nsec = (le32_to_cpu(extra) & EXT4_NSEC_MASK) >> EXT4_EPOCH_BITS;
 744 }
 745
 746 #define EXT4_INODE_SET_XTIME(xtime, inode, raw_inode)                          \
 747 do {                                                                           \
 748         (raw_inode)->xtime = cpu_to_le32((inode)->xtime.tv_sec);               \
 749         if (EXT4_FITS_IN_INODE(raw_inode, EXT4_I(inode), xtime ## _extra))     \
 750                 (raw_inode)->xtime ## _extra =                                 \
 751                                 ext4_encode_extra_time(&(inode)->xtime);       \
 752 } while (0)
 753
 754 #define EXT4_EINODE_SET_XTIME(xtime, einode, raw_inode)                        \
 755 do {                                                                           \
 756         if (EXT4_FITS_IN_INODE(raw_inode, einode, xtime))                      \
 757                 (raw_inode)->xtime = cpu_to_le32((einode)->xtime.tv_sec);      \
 758         if (EXT4_FITS_IN_INODE(raw_inode, einode, xtime ## _extra))            \
 759                 (raw_inode)->xtime ## _extra =                                 \
 760                                 ext4_encode_extra_time(&(einode)->xtime);      \
 761 } while (0)
 762
 763 #define EXT4_INODE_GET_XTIME(xtime, inode, raw_inode)                          \
 764 do {                                                                           \
 765         (inode)->xtime.tv_sec = (signed)le32_to_cpu((raw_inode)->xtime);       \
 766         if (EXT4_FITS_IN_INODE(raw_inode, EXT4_I(inode), xtime ## _extra))     \
 767                 ext4_decode_extra_time(&(inode)->xtime,                        \
 768                                        raw_inode->xtime ## _extra);            \
 769         else                                                                   \
 770                 (inode)->xtime.tv_nsec = 0;                                    \
 771 } while (0)
 772
 773 #define EXT4_EINODE_GET_XTIME(xtime, einode, raw_inode)                        \
 774 do {                                                                           \
 775         if (EXT4_FITS_IN_INODE(raw_inode, einode, xtime))                      \
 776                 (einode)->xtime.tv_sec =                                       \
 777                         (signed)le32_to_cpu((raw_inode)->xtime);               \
 778         if (EXT4_FITS_IN_INODE(raw_inode, einode, xtime ## _extra))            \
 779                 ext4_decode_extra_time(&(einode)->xtime,                       \
 780                                        raw_inode->xtime ## _extra);            \
 781         else                                                                   \
 782                 (einode)->xtime.tv_nsec = 0;                                   \
 783 } while (0)
 784
 785 #define i_disk_version osd1.linux1.l_i_version
 786
 787 #if defined(__KERNEL__) || defined(__linux__)
 788 #define i_reserved1     osd1.linux1.l_i_reserved1
 789 #define i_file_acl_high osd2.linux2.l_i_file_acl_high
 790 #define i_blocks_high   osd2.linux2.l_i_blocks_high
 791 #define i_uid_low       i_uid
 792 #define i_gid_low       i_gid
 793 #define i_uid_high      osd2.linux2.l_i_uid_high
 794 #define i_gid_high      osd2.linux2.l_i_gid_high
 795 #define i_checksum_lo   osd2.linux2.l_i_checksum_lo
 796
 797 #elif defined(__GNU__)
 798
 799 #define i_translator    osd1.hurd1.h_i_translator
 800 #define i_uid_high      osd2.hurd2.h_i_uid_high
 801 #define i_gid_high      osd2.hurd2.h_i_gid_high
 802 #define i_author        osd2.hurd2.h_i_author
 803
 804 #elif defined(__masix__)
 805
 806 #define i_reserved1     osd1.masix1.m_i_reserved1
 807 #define i_file_acl_high osd2.masix2.m_i_file_acl_high
 808 #define i_reserved2     osd2.masix2.m_i_reserved2
 809
 810 #endif /* defined(__KERNEL__) || defined(__linux__) */
 811
 812 #include "extents_status.h"
 813
 814 /*
 815  * fourth extended file system inode data in memory
 816  */
 817 struct 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         /*
 837          * Extended attributes can be read independently of the main file
 838          * data. Taking i_mutex even when reading would cause contention
 839          * between readers of EAs and writers of regular file data, so
 840          * instead we synchronize on xattr_sem when reading or changing
 841          * EAs.
 842          */
 843         struct rw_semaphore xattr_sem;
 844
 845         struct list_head i_orphan;      /* unlinked but open inodes */
 846
 847         /*
 848          * i_disksize keeps track of what the inode size is ON DISK, not
 849          * in memory.  During truncate, i_size is set to the new size by
 850          * the VFS prior to calling ext4_truncate(), but the filesystem won't
 851          * set i_disksize to 0 until the truncate is actually under way.
 852          *
 853          * The intent is that i_disksize always represents the blocks which
 854          * are used by this file.  This allows recovery to restart truncate
 855          * on orphans if we crash during truncate.  We actually write i_disksize
 856          * into the on-disk inode when writing inodes out, instead of i_size.
 857          *
 858          * The only time when i_disksize and i_size may be different is when
 859          * a truncate is in progress.  The only things which change i_disksize
 860          * are ext4_get_block (growth) and ext4_truncate (shrinkth).
 861          */
 862         loff_t  i_disksize;
 863
 864         /*
 865          * i_data_sem is for serialising ext4_truncate() against
 866          * ext4_getblock().  In the 2.4 ext2 design, great chunks of inode's
 867          * data tree are chopped off during truncate. We can't do that in
 868          * ext4 because whenever we perform intermediate commits during
 869          * truncate, the inode and all the metadata blocks *must* be in a
 870          * consistent state which allows truncation of the orphans to restart
 871          * during recovery.  Hence we must fix the get_block-vs-truncate race
 872          * by other means, so we have i_data_sem.
 873          */
 874         struct rw_semaphore i_data_sem;
 875         struct inode vfs_inode;
 876         struct jbd2_inode *jinode;
 877
 878         /*
 879          * File creation time. Its function is same as that of
 880          * struct timespec i_{a,c,m}time in the generic inode.
 881          */
 882         struct timespec i_crtime;
 883
 884         /* mballoc */
 885         struct list_head i_prealloc_list;
 886         spinlock_t i_prealloc_lock;
 887
 888         /* extents status tree */
 889         struct ext4_es_tree i_es_tree;
 890         rwlock_t i_es_lock;
 891
 892         /* ialloc */
 893         ext4_group_t    i_last_alloc_group;
 894
 895         /* allocation reservation info for delalloc */
 896         /* In case of bigalloc, these refer to clusters rather than blocks */
 897         unsigned int i_reserved_data_blocks;
 898         unsigned int i_reserved_meta_blocks;
 899         unsigned int i_allocated_meta_blocks;
 900         ext4_lblk_t i_da_metadata_calc_last_lblock;
 901         int i_da_metadata_calc_len;
 902
 903         /* on-disk additional length */
 904         __u16 i_extra_isize;
 905
 906         /* Indicate the inline data space. */
 907         u16 i_inline_off;
 908         u16 i_inline_size;
 909
 910 #ifdef CONFIG_QUOTA
 911         /* quota space reservation, managed internally by quota code */
 912         qsize_t i_reserved_quota;
 913 #endif
 914
 915         /* completed IOs that might need unwritten extents handling */
 916         struct list_head i_completed_io_list;
 917         spinlock_t i_completed_io_lock;
 918         atomic_t i_ioend_count; /* Number of outstanding io_end structs */
 919         atomic_t i_unwritten; /* Nr. of inflight conversions pending */
 920         struct work_struct i_unwritten_work;    /* deferred extent conversion */
 921
 922         spinlock_t i_block_reservation_lock;
 923
 924         /*
 925          * Transactions that contain inode's metadata needed to complete
 926          * fsync and fdatasync, respectively.
 927          */
 928         tid_t i_sync_tid;
 929         tid_t i_datasync_tid;
 930
 931         /* Precomputed uuid+inum+igen checksum for seeding inode checksums */
 932         __u32 i_csum_seed;
 933 };
 934
 935 /*
 936  * File system states
 937  */
 938 #define EXT4_VALID_FS                   0x0001  /* Unmounted cleanly */
 939 #define EXT4_ERROR_FS                   0x0002  /* Errors detected */
 940 #define EXT4_ORPHAN_FS                  0x0004  /* Orphans being recovered */
 941
 942 /*
 943  * Misc. filesystem flags
 944  */
 945 #define EXT2_FLAGS_SIGNED_HASH          0x0001  /* Signed dirhash in use */
 946 #define EXT2_FLAGS_UNSIGNED_HASH        0x0002  /* Unsigned dirhash in use */
 947 #define EXT2_FLAGS_TEST_FILESYS         0x0004  /* to test development code */
 948
 949 /*
 950  * Mount flags
 951  */
 952 #define EXT4_MOUNT_GRPID                0x00004 /* Create files with directory's group */
 953 #define EXT4_MOUNT_DEBUG                0x00008 /* Some debugging messages */
 954 #define EXT4_MOUNT_ERRORS_CONT          0x00010 /* Continue on errors */
 955 #define EXT4_MOUNT_ERRORS_RO            0x00020 /* Remount fs ro on errors */
 956 #define EXT4_MOUNT_ERRORS_PANIC         0x00040 /* Panic on errors */
 957 #define EXT4_MOUNT_ERRORS_MASK          0x00070
 958 #define EXT4_MOUNT_MINIX_DF             0x00080 /* Mimics the Minix statfs */
 959 #define EXT4_MOUNT_NOLOAD               0x00100 /* Don't use existing journal*/
 960 #define EXT4_MOUNT_DATA_FLAGS           0x00C00 /* Mode for data writes: */
 961 #define EXT4_MOUNT_JOURNAL_DATA         0x00400 /* Write data to journal */
 962 #define EXT4_MOUNT_ORDERED_DATA         0x00800 /* Flush data before commit */
 963 #define EXT4_MOUNT_WRITEBACK_DATA       0x00C00 /* No data ordering */
 964 #define EXT4_MOUNT_UPDATE_JOURNAL       0x01000 /* Update the journal format */
 965 #define EXT4_MOUNT_NO_UID32             0x02000  /* Disable 32-bit UIDs */
 966 #define EXT4_MOUNT_XATTR_USER           0x04000 /* Extended user attributes */
 967 #define EXT4_MOUNT_POSIX_ACL            0x08000 /* POSIX Access Control Lists */
 968 #define EXT4_MOUNT_NO_AUTO_DA_ALLOC     0x10000 /* No auto delalloc mapping */
 969 #define EXT4_MOUNT_BARRIER              0x20000 /* Use block barriers */
 970 #define EXT4_MOUNT_QUOTA                0x80000 /* Some quota option set */
 971 #define EXT4_MOUNT_USRQUOTA             0x100000 /* "old" user quota */
 972 #define EXT4_MOUNT_GRPQUOTA             0x200000 /* "old" group quota */
 973 #define EXT4_MOUNT_DIOREAD_NOLOCK       0x400000 /* Enable support for dio read nolocking */
 974 #define EXT4_MOUNT_JOURNAL_CHECKSUM     0x800000 /* Journal checksums */
 975 #define EXT4_MOUNT_JOURNAL_ASYNC_COMMIT 0x1000000 /* Journal Async Commit */
 976 #define EXT4_MOUNT_DELALLOC             0x8000000 /* Delalloc support */
 977 #define EXT4_MOUNT_DATA_ERR_ABORT       0x10000000 /* Abort on file data write */
 978 #define EXT4_MOUNT_BLOCK_VALIDITY       0x20000000 /* Block validity checking */
 979 #define EXT4_MOUNT_DISCARD              0x40000000 /* Issue DISCARD requests */
 980 #define EXT4_MOUNT_INIT_INODE_TABLE     0x80000000 /* Initialize uninitialized itables */
 981
 982 #define EXT4_MOUNT2_EXPLICIT_DELALLOC   0x00000001 /* User explicitly
 983                                                       specified delalloc */
 984
 985 #define clear_opt(sb, opt)              EXT4_SB(sb)->s_mount_opt &= \
 986                                                 ~EXT4_MOUNT_##opt
 987 #define set_opt(sb, opt)                EXT4_SB(sb)->s_mount_opt |= \
 988                                                 EXT4_MOUNT_##opt
 989 #define test_opt(sb, opt)               (EXT4_SB(sb)->s_mount_opt & \
 990                                          EXT4_MOUNT_##opt)
 991
 992 #define clear_opt2(sb, opt)             EXT4_SB(sb)->s_mount_opt2 &= \
 993                                                 ~EXT4_MOUNT2_##opt
 994 #define set_opt2(sb, opt)               EXT4_SB(sb)->s_mount_opt2 |= \
 995                                                 EXT4_MOUNT2_##opt
 996 #define test_opt2(sb, opt)              (EXT4_SB(sb)->s_mount_opt2 & \
 997                                          EXT4_MOUNT2_##opt)
 998
 999 #define ext4_test_and_set_bit           __test_and_set_bit_le
1000 #define ext4_set_bit                    __set_bit_le
1001 #define ext4_set_bit_atomic             ext2_set_bit_atomic
1002 #define ext4_test_and_clear_bit         __test_and_clear_bit_le
1003 #define ext4_clear_bit                  __clear_bit_le
1004 #define ext4_clear_bit_atomic           ext2_clear_bit_atomic
1005 #define ext4_test_bit                   test_bit_le
1006 #define ext4_find_next_zero_bit         find_next_zero_bit_le
1007 #define ext4_find_next_bit              find_next_bit_le
1008
1009 extern void ext4_set_bits(void *bm, int cur, int len);
1010
1011 /*
1012  * Maximal mount counts between two filesystem checks
1013  */
1014 #define EXT4_DFL_MAX_MNT_COUNT          20      /* Allow 20 mounts */
1015 #define EXT4_DFL_CHECKINTERVAL          0       /* Don't use interval check */
1016
1017 /*
1018  * Behaviour when detecting errors
1019  */
1020 #define EXT4_ERRORS_CONTINUE            1       /* Continue execution */
1021 #define EXT4_ERRORS_RO                  2       /* Remount fs read-only */
1022 #define EXT4_ERRORS_PANIC               3       /* Panic */
1023 #define EXT4_ERRORS_DEFAULT             EXT4_ERRORS_CONTINUE
1024
1025 /* Metadata checksum algorithm codes */
1026 #define EXT4_CRC32C_CHKSUM              1
1027
1028 /*
1029  * Structure of the super block
1030  */
1031 struct ext4_super_block {
1032 /*00*/  __le32  s_inodes_count;         /* Inodes count */
1033         __le32  s_blocks_count_lo;      /* Blocks count */
1034         __le32  s_r_blocks_count_lo;    /* Reserved blocks count */
1035         __le32  s_free_blocks_count_lo; /* Free blocks count */
1036 /*10*/  __le32  s_free_inodes_count;    /* Free inodes count */
1037         __le32  s_first_data_block;     /* First Data Block */
1038         __le32  s_log_block_size;       /* Block size */
1039         __le32  s_log_cluster_size;     /* Allocation cluster size */
1040 /*20*/  __le32  s_blocks_per_group;     /* # Blocks per group */
1041         __le32  s_clusters_per_group;   /* # Clusters per group */
1042         __le32  s_inodes_per_group;     /* # Inodes per group */
1043         __le32  s_mtime;                /* Mount time */
1044 /*30*/  __le32  s_wtime;                /* Write time */
1045         __le16  s_mnt_count;            /* Mount count */
1046         __le16  s_max_mnt_count;        /* Maximal mount count */
1047         __le16  s_magic;                /* Magic signature */
1048         __le16  s_state;                /* File system state */
1049         __le16  s_errors;               /* Behaviour when detecting errors */
1050         __le16  s_minor_rev_level;      /* minor revision level */
1051 /*40*/  __le32  s_lastcheck;            /* time of last check */
1052         __le32  s_checkinterval;        /* max. time between checks */
1053         __le32  s_creator_os;           /* OS */
1054         __le32  s_rev_level;            /* Revision level */
1055 /*50*/  __le16  s_def_resuid;           /* Default uid for reserved blocks */
1056         __le16  s_def_resgid;           /* Default gid for reserved blocks */
1057         /*
1058          * These fields are for EXT4_DYNAMIC_REV superblocks only.
1059          *
1060          * Note: the difference between the compatible feature set and
1061          * the incompatible feature set is that if there is a bit set
1062          * in the incompatible feature set that the kernel doesn't
1063          * know about, it should refuse to mount the filesystem.
1064          *
1065          * e2fsck's requirements are more strict; if it doesn't know
1066          * about a feature in either the compatible or incompatible
1067          * feature set, it must abort and not try to meddle with
1068          * things it doesn't understand...
1069          */
1070         __le32  s_first_ino;            /* First non-reserved inode */
1071         __le16  s_inode_size;           /* size of inode structure */
1072         __le16  s_block_group_nr;       /* block group # of this superblock */
1073         __le32  s_feature_compat;       /* compatible feature set */
1074 /*60*/  __le32  s_feature_incompat;     /* incompatible feature set */
1075         __le32  s_feature_ro_compat;    /* readonly-compatible feature set */
1076 /*68*/  __u8    s_uuid[16];             /* 128-bit uuid for volume */
1077 /*78*/  char    s_volume_name[16];      /* volume name */
1078 /*88*/  char    s_last_mounted[64];     /* directory where last mounted */
1079 /*C8*/  __le32  s_algorithm_usage_bitmap; /* For compression */
1080         /*
1081          * Performance hints.  Directory preallocation should only
1082          * happen if the EXT4_FEATURE_COMPAT_DIR_PREALLOC flag is on.
1083          */
1084         __u8    s_prealloc_blocks;      /* Nr of blocks to try to preallocate*/
1085         __u8    s_prealloc_dir_blocks;  /* Nr to preallocate for dirs */
1086         __le16  s_reserved_gdt_blocks;  /* Per group desc for online growth */
1087         /*
1088          * Journaling support valid if EXT4_FEATURE_COMPAT_HAS_JOURNAL set.
1089          */
1090 /*D0*/  __u8    s_journal_uuid[16];     /* uuid of journal superblock */
1091 /*E0*/  __le32  s_journal_inum;         /* inode number of journal file */
1092         __le32  s_journal_dev;          /* device number of journal file */
1093         __le32  s_last_orphan;          /* start of list of inodes to delete */
1094         __le32  s_hash_seed[4];         /* HTREE hash seed */
1095         __u8    s_def_hash_version;     /* Default hash version to use */
1096         __u8    s_jnl_backup_type;
1097         __le16  s_desc_size;            /* size of group descriptor */
1098 /*100*/ __le32  s_default_mount_opts;
1099         __le32  s_first_meta_bg;        /* First metablock block group */
1100         __le32  s_mkfs_time;            /* When the filesystem was created */
1101         __le32  s_jnl_blocks[17];       /* Backup of the journal inode */
1102         /* 64bit support valid if EXT4_FEATURE_COMPAT_64BIT */
1103 /*150*/ __le32  s_blocks_count_hi;      /* Blocks count */
1104         __le32  s_r_blocks_count_hi;    /* Reserved blocks count */
1105         __le32  s_free_blocks_count_hi; /* Free blocks count */
1106         __le16  s_min_extra_isize;      /* All inodes have at least # bytes */
1107         __le16  s_want_extra_isize;     /* New inodes should reserve # bytes */
1108         __le32  s_flags;                /* Miscellaneous flags */
1109         __le16  s_raid_stride;          /* RAID stride */
1110         __le16  s_mmp_update_interval;  /* # seconds to wait in MMP checking */
1111         __le64  s_mmp_block;            /* Block for multi-mount protection */
1112         __le32  s_raid_stripe_width;    /* blocks on all data disks (N*stride)*/
1113         __u8    s_log_groups_per_flex;  /* FLEX_BG group size */
1114         __u8    s_checksum_type;        /* metadata checksum algorithm used */
1115         __le16  s_reserved_pad;
1116         __le64  s_kbytes_written;       /* nr of lifetime kilobytes written */
1117         __le32  s_snapshot_inum;        /* Inode number of active snapshot */
1118         __le32  s_snapshot_id;          /* sequential ID of active snapshot */
1119         __le64  s_snapshot_r_blocks_count; /* reserved blocks for active
1120                                               snapshot's future use */
1121         __le32  s_snapshot_list;        /* inode number of the head of the
1122                                            on-disk snapshot list */
1123 #define EXT4_S_ERR_START offsetof(struct ext4_super_block, s_error_count)
1124         __le32  s_error_count;          /* number of fs errors */
1125         __le32  s_first_error_time;     /* first time an error happened */
1126         __le32  s_first_error_ino;      /* inode involved in first error */
1127         __le64  s_first_error_block;    /* block involved of first error */
1128         __u8    s_first_error_func[32]; /* function where the error happened */
1129         __le32  s_first_error_line;     /* line number where error happened */
1130         __le32  s_last_error_time;      /* most recent time of an error */
1131         __le32  s_last_error_ino;       /* inode involved in last error */
1132         __le32  s_last_error_line;      /* line number where error happened */
1133         __le64  s_last_error_block;     /* block involved of last error */
1134         __u8    s_last_error_func[32];  /* function where the error happened */
1135 #define EXT4_S_ERR_END offsetof(struct ext4_super_block, s_mount_opts)
1136         __u8    s_mount_opts[64];
1137         __le32  s_usr_quota_inum;       /* inode for tracking user quota */
1138         __le32  s_grp_quota_inum;       /* inode for tracking group quota */
1139         __le32  s_overhead_clusters;    /* overhead blocks/clusters in fs */
1140         __le32  s_reserved[108];        /* Padding to the end of the block */
1141         __le32  s_checksum;             /* crc32c(superblock) */
1142 };
1143
1144 #define EXT4_S_ERR_LEN (EXT4_S_ERR_END - EXT4_S_ERR_START)
1145
1146 #ifdef __KERNEL__
1147
1148 /*
1149  * run-time mount flags
1150  */
1151 #define EXT4_MF_MNTDIR_SAMPLED  0x0001
1152 #define EXT4_MF_FS_ABORTED      0x0002  /* Fatal error detected */
1153
1154 /*
1155  * fourth extended-fs super-block data in memory
1156  */
1157 struct ext4_sb_info {
1158         unsigned long s_desc_size;      /* Size of a group descriptor in bytes */
1159         unsigned long s_inodes_per_block;/* Number of inodes per block */
1160         unsigned long s_blocks_per_group;/* Number of blocks in a group */
1161         unsigned long s_clusters_per_group; /* Number of clusters in a group */
1162         unsigned long s_inodes_per_group;/* Number of inodes in a group */
1163         unsigned long s_itb_per_group;  /* Number of inode table blocks per group */
1164         unsigned long s_gdb_count;      /* Number of group descriptor blocks */
1165         unsigned long s_desc_per_block; /* Number of group descriptors per block */
1166         ext4_group_t s_groups_count;    /* Number of groups in the fs */
1167         ext4_group_t s_blockfile_groups;/* Groups acceptable for non-extent files */
1168         unsigned long s_overhead;  /* # of fs overhead clusters */
1169         unsigned int s_cluster_ratio;   /* Number of blocks per cluster */
1170         unsigned int s_cluster_bits;    /* log2 of s_cluster_ratio */
1171         loff_t s_bitmap_maxbytes;       /* max bytes for bitmap files */
1172         struct buffer_head * s_sbh;     /* Buffer containing the super block */
1173         struct ext4_super_block *s_es;  /* Pointer to the super block in the buffer */
1174         struct buffer_head **s_group_desc;
1175         unsigned int s_mount_opt;
1176         unsigned int s_mount_opt2;
1177         unsigned int s_mount_flags;
1178         unsigned int s_def_mount_opt;
1179         ext4_fsblk_t s_sb_block;
1180         kuid_t s_resuid;
1181         kgid_t s_resgid;
1182         unsigned short s_mount_state;
1183         unsigned short s_pad;
1184         int s_addr_per_block_bits;
1185         int s_desc_per_block_bits;
1186         int s_inode_size;
1187         int s_first_ino;
1188         unsigned int s_inode_readahead_blks;
1189         unsigned int s_inode_goal;
1190         spinlock_t s_next_gen_lock;
1191         u32 s_next_generation;
1192         u32 s_hash_seed[4];
1193         int s_def_hash_version;
1194         int s_hash_unsigned;    /* 3 if hash should be signed, 0 if not */
1195         struct percpu_counter s_freeclusters_counter;
1196         struct percpu_counter s_freeinodes_counter;
1197         struct percpu_counter s_dirs_counter;
1198         struct percpu_counter s_dirtyclusters_counter;
1199         struct blockgroup_lock *s_blockgroup_lock;
1200         struct proc_dir_entry *s_proc;
1201         struct kobject s_kobj;
1202         struct completion s_kobj_unregister;
1203         struct super_block *s_sb;
1204
1205         /* Journaling */
1206         struct journal_s *s_journal;
1207         struct list_head s_orphan;
1208         struct mutex s_orphan_lock;
1209         unsigned long s_resize_flags;           /* Flags indicating if there
1210                                                    is a resizer */
1211         unsigned long s_commit_interval;
1212         u32 s_max_batch_time;
1213         u32 s_min_batch_time;
1214         struct block_device *journal_bdev;
1215 #ifdef CONFIG_QUOTA
1216         char *s_qf_names[MAXQUOTAS];            /* Names of quota files with journalled quota */
1217         int s_jquota_fmt;                       /* Format of quota to use */
1218 #endif
1219         unsigned int s_want_extra_isize; /* New inodes should reserve # bytes */
1220         struct rb_root system_blks;
1221
1222 #ifdef EXTENTS_STATS
1223         /* ext4 extents stats */
1224         unsigned long s_ext_min;
1225         unsigned long s_ext_max;
1226         unsigned long s_depth_max;
1227         spinlock_t s_ext_stats_lock;
1228         unsigned long s_ext_blocks;
1229         unsigned long s_ext_extents;
1230 #endif
1231
1232         /* for buddy allocator */
1233         struct ext4_group_info ***s_group_info;
1234         struct inode *s_buddy_cache;
1235         spinlock_t s_md_lock;
1236         unsigned short *s_mb_offsets;
1237         unsigned int *s_mb_maxs;
1238         unsigned int s_group_info_size;
1239
1240         /* tunables */
1241         unsigned long s_stripe;
1242         unsigned int s_mb_stream_request;
1243         unsigned int s_mb_max_to_scan;
1244         unsigned int s_mb_min_to_scan;
1245         unsigned int s_mb_stats;
1246         unsigned int s_mb_order2_reqs;
1247         unsigned int s_mb_group_prealloc;
1248         unsigned int s_max_writeback_mb_bump;
1249         unsigned int s_max_dir_size_kb;
1250         /* where last allocation was done - for stream allocation */
1251         unsigned long s_mb_last_group;
1252         unsigned long s_mb_last_start;
1253
1254         /* stats for buddy allocator */
1255         atomic_t s_bal_reqs;    /* number of reqs with len > 1 */
1256         atomic_t s_bal_success; /* we found long enough chunks */
1257         atomic_t s_bal_allocated;       /* in blocks */
1258         atomic_t s_bal_ex_scanned;      /* total extents scanned */
1259         atomic_t s_bal_goals;   /* goal hits */
1260         atomic_t s_bal_breaks;  /* too long searches */
1261         atomic_t s_bal_2orders; /* 2^order hits */
1262         spinlock_t s_bal_lock;
1263         unsigned long s_mb_buddies_generated;
1264         unsigned long long s_mb_generation_time;
1265         atomic_t s_mb_lost_chunks;
1266         atomic_t s_mb_preallocated;
1267         atomic_t s_mb_discarded;
1268         atomic_t s_lock_busy;
1269
1270         /* locality groups */
1271         struct ext4_locality_group __percpu *s_locality_groups;
1272
1273         /* for write statistics */
1274         unsigned long s_sectors_written_start;
1275         u64 s_kbytes_written;
1276
1277         /* the size of zero-out chunk */
1278         unsigned int s_extent_max_zeroout_kb;
1279
1280         unsigned int s_log_groups_per_flex;
1281         struct flex_groups *s_flex_groups;
1282         ext4_group_t s_flex_groups_allocated;
1283
1284         /* workqueue for dio unwritten */
1285         struct workqueue_struct *dio_unwritten_wq;
1286
1287         /* timer for periodic error stats printing */
1288         struct timer_list s_err_report;
1289
1290         /* Lazy inode table initialization info */
1291         struct ext4_li_request *s_li_request;
1292         /* Wait multiplier for lazy initialization thread */
1293         unsigned int s_li_wait_mult;
1294
1295         /* Kernel thread for multiple mount protection */
1296         struct task_struct *s_mmp_tsk;
1297
1298         /* record the last minlen when FITRIM is called. */
1299         atomic_t s_last_trim_minblks;
1300
1301         /* Reference to checksum algorithm driver via cryptoapi */
1302         struct crypto_shash *s_chksum_driver;
1303
1304         /* Precomputed FS UUID checksum for seeding other checksums */
1305         __u32 s_csum_seed;
1306 };
1307
1308 static inline struct ext4_sb_info *EXT4_SB(struct super_block *sb)
1309 {
1310         return sb->s_fs_info;
1311 }
1312 static inline struct ext4_inode_info *EXT4_I(struct inode *inode)
1313 {
1314         return container_of(inode, struct ext4_inode_info, vfs_inode);
1315 }
1316
1317 static inline struct timespec ext4_current_time(struct inode *inode)
1318 {
1319         return (inode->i_sb->s_time_gran < NSEC_PER_SEC) ?
1320                 current_fs_time(inode->i_sb) : CURRENT_TIME_SEC;
1321 }
1322
1323 static inline int ext4_valid_inum(struct super_block *sb, unsigned long ino)
1324 {
1325         return ino == EXT4_ROOT_INO ||
1326                 ino == EXT4_USR_QUOTA_INO ||
1327                 ino == EXT4_GRP_QUOTA_INO ||
1328                 ino == EXT4_JOURNAL_INO ||
1329                 ino == EXT4_RESIZE_INO ||
1330                 (ino >= EXT4_FIRST_INO(sb) &&
1331                  ino <= le32_to_cpu(EXT4_SB(sb)->s_es->s_inodes_count));
1332 }
1333
1334 static inline void ext4_set_io_unwritten_flag(struct inode *inode,
1335                                               struct ext4_io_end *io_end)
1336 {
1337         if (!(io_end->flag & EXT4_IO_END_UNWRITTEN)) {
1338                 io_end->flag |= EXT4_IO_END_UNWRITTEN;
1339                 atomic_inc(&EXT4_I(inode)->i_unwritten);
1340         }
1341 }
1342
1343 static inline ext4_io_end_t *ext4_inode_aio(struct inode *inode)
1344 {
1345         return inode->i_private;
1346 }
1347
1348 static inline void ext4_inode_aio_set(struct inode *inode, ext4_io_end_t *io)
1349 {
1350         inode->i_private = io;
1351 }
1352
1353 /*
1354  * Inode dynamic state flags
1355  */
1356 enum {
1357         EXT4_STATE_JDATA,               /* journaled data exists */
1358         EXT4_STATE_NEW,                 /* inode is newly created */
1359         EXT4_STATE_XATTR,               /* has in-inode xattrs */
1360         EXT4_STATE_NO_EXPAND,           /* No space for expansion */
1361         EXT4_STATE_DA_ALLOC_CLOSE,      /* Alloc DA blks on close */
1362         EXT4_STATE_EXT_MIGRATE,         /* Inode is migrating */
1363         EXT4_STATE_DIO_UNWRITTEN,       /* need convert on dio done*/
1364         EXT4_STATE_NEWENTRY,            /* File just added to dir */
1365         EXT4_STATE_DELALLOC_RESERVED,   /* blks already reserved for delalloc */
1366         EXT4_STATE_DIOREAD_LOCK,        /* Disable support for dio read
1367                                            nolocking */
1368         EXT4_STATE_MAY_INLINE_DATA,     /* may have in-inode data */
1369 };
1370
1371 #define EXT4_INODE_BIT_FNS(name, field, offset)                         \
1372 static inline int ext4_test_inode_##name(struct inode *inode, int bit)  \
1373 {                                                                       \
1374         return test_bit(bit + (offset), &EXT4_I(inode)->i_##field);     \
1375 }                                                                       \
1376 static inline void ext4_set_inode_##name(struct inode *inode, int bit)  \
1377 {                                                                       \
1378         set_bit(bit + (offset), &EXT4_I(inode)->i_##field);             \
1379 }                                                                       \
1380 static inline void ext4_clear_inode_##name(struct inode *inode, int bit) \
1381 {                                                                       \
1382         clear_bit(bit + (offset), &EXT4_I(inode)->i_##field);           \
1383 }
1384
1385 EXT4_INODE_BIT_FNS(flag, flags, 0)
1386 #if (BITS_PER_LONG < 64)
1387 EXT4_INODE_BIT_FNS(state, state_flags, 0)
1388
1389 static inline void ext4_clear_state_flags(struct ext4_inode_info *ei)
1390 {
1391         (ei)->i_state_flags = 0;
1392 }
1393 #else
1394 EXT4_INODE_BIT_FNS(state, flags, 32)
1395
1396 static inline void ext4_clear_state_flags(struct ext4_inode_info *ei)
1397 {
1398         /* We depend on the fact that callers will set i_flags */
1399 }
1400 #endif
1401 #else
1402 /* Assume that user mode programs are passing in an ext4fs superblock, not
1403  * a kernel struct super_block.  This will allow us to call the feature-test
1404  * macros from user land. */
1405 #define EXT4_SB(sb)     (sb)
1406 #endif
1407
1408 #define NEXT_ORPHAN(inode) EXT4_I(inode)->i_dtime
1409
1410 /*
1411  * Codes for operating systems
1412  */
1413 #define EXT4_OS_LINUX           0
1414 #define EXT4_OS_HURD            1
1415 #define EXT4_OS_MASIX           2
1416 #define EXT4_OS_FREEBSD         3
1417 #define EXT4_OS_LITES           4
1418
1419 /*
1420  * Revision levels
1421  */
1422 #define EXT4_GOOD_OLD_REV       0       /* The good old (original) format */
1423 #define EXT4_DYNAMIC_REV        1       /* V2 format w/ dynamic inode sizes */
1424
1425 #define EXT4_CURRENT_REV        EXT4_GOOD_OLD_REV
1426 #define EXT4_MAX_SUPP_REV       EXT4_DYNAMIC_REV
1427
1428 #define EXT4_GOOD_OLD_INODE_SIZE 128
1429
1430 /*
1431  * Feature set definitions
1432  */
1433
1434 #define EXT4_HAS_COMPAT_FEATURE(sb,mask)                        \
1435         ((EXT4_SB(sb)->s_es->s_feature_compat & cpu_to_le32(mask)) != 0)
1436 #define EXT4_HAS_RO_COMPAT_FEATURE(sb,mask)                     \
1437         ((EXT4_SB(sb)->s_es->s_feature_ro_compat & cpu_to_le32(mask)) != 0)
1438 #define EXT4_HAS_INCOMPAT_FEATURE(sb,mask)                      \
1439         ((EXT4_SB(sb)->s_es->s_feature_incompat & cpu_to_le32(mask)) != 0)
1440 #define EXT4_SET_COMPAT_FEATURE(sb,mask)                        \
1441         EXT4_SB(sb)->s_es->s_feature_compat |= cpu_to_le32(mask)
1442 #define EXT4_SET_RO_COMPAT_FEATURE(sb,mask)                     \
1443         EXT4_SB(sb)->s_es->s_feature_ro_compat |= cpu_to_le32(mask)
1444 #define EXT4_SET_INCOMPAT_FEATURE(sb,mask)                      \
1445         EXT4_SB(sb)->s_es->s_feature_incompat |= cpu_to_le32(mask)
1446 #define EXT4_CLEAR_COMPAT_FEATURE(sb,mask)                      \
1447         EXT4_SB(sb)->s_es->s_feature_compat &= ~cpu_to_le32(mask)
1448 #define EXT4_CLEAR_RO_COMPAT_FEATURE(sb,mask)                   \
1449         EXT4_SB(sb)->s_es->s_feature_ro_compat &= ~cpu_to_le32(mask)
1450 #define EXT4_CLEAR_INCOMPAT_FEATURE(sb,mask)                    \
1451         EXT4_SB(sb)->s_es->s_feature_incompat &= ~cpu_to_le32(mask)
1452
1453 #define EXT4_FEATURE_COMPAT_DIR_PREALLOC        0x0001
1454 #define EXT4_FEATURE_COMPAT_IMAGIC_INODES       0x0002
1455 #define EXT4_FEATURE_COMPAT_HAS_JOURNAL         0x0004
1456 #define EXT4_FEATURE_COMPAT_EXT_ATTR            0x0008
1457 #define EXT4_FEATURE_COMPAT_RESIZE_INODE        0x0010
1458 #define EXT4_FEATURE_COMPAT_DIR_INDEX           0x0020
1459
1460 #define EXT4_FEATURE_RO_COMPAT_SPARSE_SUPER     0x0001
1461 #define EXT4_FEATURE_RO_COMPAT_LARGE_FILE       0x0002
1462 #define EXT4_FEATURE_RO_COMPAT_BTREE_DIR        0x0004
1463 #define EXT4_FEATURE_RO_COMPAT_HUGE_FILE        0x0008
1464 #define EXT4_FEATURE_RO_COMPAT_GDT_CSUM         0x0010
1465 #define EXT4_FEATURE_RO_COMPAT_DIR_NLINK        0x0020
1466 #define EXT4_FEATURE_RO_COMPAT_EXTRA_ISIZE      0x0040
1467 #define EXT4_FEATURE_RO_COMPAT_QUOTA            0x0100
1468 #define EXT4_FEATURE_RO_COMPAT_BIGALLOC         0x0200
1469 /*
1470  * METADATA_CSUM also enables group descriptor checksums (GDT_CSUM).  When
1471  * METADATA_CSUM is set, group descriptor checksums use the same algorithm as
1472  * all other data structures' checksums.  However, the METADATA_CSUM and
1473  * GDT_CSUM bits are mutually exclusive.
1474  */
1475 #define EXT4_FEATURE_RO_COMPAT_METADATA_CSUM    0x0400
1476
1477 #define EXT4_FEATURE_INCOMPAT_COMPRESSION       0x0001
1478 #define EXT4_FEATURE_INCOMPAT_FILETYPE          0x0002
1479 #define EXT4_FEATURE_INCOMPAT_RECOVER           0x0004 /* Needs recovery */
1480 #define EXT4_FEATURE_INCOMPAT_JOURNAL_DEV       0x0008 /* Journal device */
1481 #define EXT4_FEATURE_INCOMPAT_META_BG           0x0010
1482 #define EXT4_FEATURE_INCOMPAT_EXTENTS           0x0040 /* extents support */
1483 #define EXT4_FEATURE_INCOMPAT_64BIT             0x0080
1484 #define EXT4_FEATURE_INCOMPAT_MMP               0x0100
1485 #define EXT4_FEATURE_INCOMPAT_FLEX_BG           0x0200
1486 #define EXT4_FEATURE_INCOMPAT_EA_INODE          0x0400 /* EA in inode */
1487 #define EXT4_FEATURE_INCOMPAT_DIRDATA           0x1000 /* data in dirent */
1488 #define EXT4_FEATURE_INCOMPAT_BG_USE_META_CSUM  0x2000 /* use crc32c for bg */
1489 #define EXT4_FEATURE_INCOMPAT_LARGEDIR          0x4000 /* >2GB or 3-lvl htree */
1490 #define EXT4_FEATURE_INCOMPAT_INLINE_DATA       0x8000 /* data in inode */
1491
1492 #define EXT2_FEATURE_COMPAT_SUPP        EXT4_FEATURE_COMPAT_EXT_ATTR
1493 #define EXT2_FEATURE_INCOMPAT_SUPP      (EXT4_FEATURE_INCOMPAT_FILETYPE| \
1494                                          EXT4_FEATURE_INCOMPAT_META_BG)
1495 #define EXT2_FEATURE_RO_COMPAT_SUPP     (EXT4_FEATURE_RO_COMPAT_SPARSE_SUPER| \
1496                                          EXT4_FEATURE_RO_COMPAT_LARGE_FILE| \
1497                                          EXT4_FEATURE_RO_COMPAT_BTREE_DIR)
1498
1499 #define EXT3_FEATURE_COMPAT_SUPP        EXT4_FEATURE_COMPAT_EXT_ATTR
1500 #define EXT3_FEATURE_INCOMPAT_SUPP      (EXT4_FEATURE_INCOMPAT_FILETYPE| \
1501                                          EXT4_FEATURE_INCOMPAT_RECOVER| \
1502                                          EXT4_FEATURE_INCOMPAT_META_BG)
1503 #define EXT3_FEATURE_RO_COMPAT_SUPP     (EXT4_FEATURE_RO_COMPAT_SPARSE_SUPER| \
1504                                          EXT4_FEATURE_RO_COMPAT_LARGE_FILE| \
1505                                          EXT4_FEATURE_RO_COMPAT_BTREE_DIR)
1506
1507 #define EXT4_FEATURE_COMPAT_SUPP        EXT2_FEATURE_COMPAT_EXT_ATTR
1508 #define EXT4_FEATURE_INCOMPAT_SUPP      (EXT4_FEATURE_INCOMPAT_FILETYPE| \
1509                                          EXT4_FEATURE_INCOMPAT_RECOVER| \
1510                                          EXT4_FEATURE_INCOMPAT_META_BG| \
1511                                          EXT4_FEATURE_INCOMPAT_EXTENTS| \
1512                                          EXT4_FEATURE_INCOMPAT_64BIT| \
1513                                          EXT4_FEATURE_INCOMPAT_FLEX_BG| \
1514                                          EXT4_FEATURE_INCOMPAT_MMP |    \
1515                                          EXT4_FEATURE_INCOMPAT_INLINE_DATA)
1516 #define EXT4_FEATURE_RO_COMPAT_SUPP     (EXT4_FEATURE_RO_COMPAT_SPARSE_SUPER| \
1517                                          EXT4_FEATURE_RO_COMPAT_LARGE_FILE| \
1518                                          EXT4_FEATURE_RO_COMPAT_GDT_CSUM| \
1519                                          EXT4_FEATURE_RO_COMPAT_DIR_NLINK | \
1520                                          EXT4_FEATURE_RO_COMPAT_EXTRA_ISIZE | \
1521                                          EXT4_FEATURE_RO_COMPAT_BTREE_DIR |\
1522                                          EXT4_FEATURE_RO_COMPAT_HUGE_FILE |\
1523                                          EXT4_FEATURE_RO_COMPAT_BIGALLOC |\
1524                                          EXT4_FEATURE_RO_COMPAT_METADATA_CSUM|\
1525                                          EXT4_FEATURE_RO_COMPAT_QUOTA)
1526
1527 /*
1528  * Default values for user and/or group using reserved blocks
1529  */
1530 #define EXT4_DEF_RESUID         0
1531 #define EXT4_DEF_RESGID         0
1532
1533 #define EXT4_DEF_INODE_READAHEAD_BLKS   32
1534
1535 /*
1536  * Default mount options
1537  */
1538 #define EXT4_DEFM_DEBUG         0x0001
1539 #define EXT4_DEFM_BSDGROUPS     0x0002
1540 #define EXT4_DEFM_XATTR_USER    0x0004
1541 #define EXT4_DEFM_ACL           0x0008
1542 #define EXT4_DEFM_UID16         0x0010
1543 #define EXT4_DEFM_JMODE         0x0060
1544 #define EXT4_DEFM_JMODE_DATA    0x0020
1545 #define EXT4_DEFM_JMODE_ORDERED 0x0040
1546 #define EXT4_DEFM_JMODE_WBACK   0x0060
1547 #define EXT4_DEFM_NOBARRIER     0x0100
1548 #define EXT4_DEFM_BLOCK_VALIDITY 0x0200
1549 #define EXT4_DEFM_DISCARD       0x0400
1550 #define EXT4_DEFM_NODELALLOC    0x0800
1551
1552 /*
1553  * Default journal batch times
1554  */
1555 #define EXT4_DEF_MIN_BATCH_TIME 0
1556 #define EXT4_DEF_MAX_BATCH_TIME 15000 /* 15ms */
1557
1558 /*
1559  * Minimum number of groups in a flexgroup before we separate out
1560  * directories into the first block group of a flexgroup
1561  */
1562 #define EXT4_FLEX_SIZE_DIR_ALLOC_SCHEME 4
1563
1564 /*
1565  * Structure of a directory entry
1566  */
1567 #define EXT4_NAME_LEN 255
1568
1569 struct ext4_dir_entry {
1570         __le32  inode;                  /* Inode number */
1571         __le16  rec_len;                /* Directory entry length */
1572         __le16  name_len;               /* Name length */
1573         char    name[EXT4_NAME_LEN];    /* File name */
1574 };
1575
1576 /*
1577  * The new version of the directory entry.  Since EXT4 structures are
1578  * stored in intel byte order, and the name_len field could never be
1579  * bigger than 255 chars, it's safe to reclaim the extra byte for the
1580  * file_type field.
1581  */
1582 struct ext4_dir_entry_2 {
1583         __le32  inode;                  /* Inode number */
1584         __le16  rec_len;                /* Directory entry length */
1585         __u8    name_len;               /* Name length */
1586         __u8    file_type;
1587         char    name[EXT4_NAME_LEN];    /* File name */
1588 };
1589
1590 /*
1591  * This is a bogus directory entry at the end of each leaf block that
1592  * records checksums.
1593  */
1594 struct ext4_dir_entry_tail {
1595         __le32  det_reserved_zero1;     /* Pretend to be unused */
1596         __le16  det_rec_len;            /* 12 */
1597         __u8    det_reserved_zero2;     /* Zero name length */
1598         __u8    det_reserved_ft;        /* 0xDE, fake file type */
1599         __le32  det_checksum;           /* crc32c(uuid+inum+dirblock) */
1600 };
1601
1602 #define EXT4_DIRENT_TAIL(block, blocksize) \
1603         ((struct ext4_dir_entry_tail *)(((void *)(block)) + \
1604                                         ((blocksize) - \
1605                                          sizeof(struct ext4_dir_entry_tail))))
1606
1607 /*
1608  * Ext4 directory file types.  Only the low 3 bits are used.  The
1609  * other bits are reserved for now.
1610  */
1611 #define EXT4_FT_UNKNOWN         0
1612 #define EXT4_FT_REG_FILE        1
1613 #define EXT4_FT_DIR             2
1614 #define EXT4_FT_CHRDEV          3
1615 #define EXT4_FT_BLKDEV          4
1616 #define EXT4_FT_FIFO            5
1617 #define EXT4_FT_SOCK            6
1618 #define EXT4_FT_SYMLINK         7
1619
1620 #define EXT4_FT_MAX             8
1621
1622 #define EXT4_FT_DIR_CSUM        0xDE
1623
1624 /*
1625  * EXT4_DIR_PAD defines the directory entries boundaries
1626  *
1627  * NOTE: It must be a multiple of 4
1628  */
1629 #define EXT4_DIR_PAD                    4
1630 #define EXT4_DIR_ROUND                  (EXT4_DIR_PAD - 1)
1631 #define EXT4_DIR_REC_LEN(name_len)      (((name_len) + 8 + EXT4_DIR_ROUND) & \
1632                                          ~EXT4_DIR_ROUND)
1633 #define EXT4_MAX_REC_LEN                ((1<<16)-1)
1634
1635 /*
1636  * If we ever get support for fs block sizes > page_size, we'll need
1637  * to remove the #if statements in the next two functions...
1638  */
1639 static inline unsigned int
1640 ext4_rec_len_from_disk(__le16 dlen, unsigned blocksize)
1641 {
1642         unsigned len = le16_to_cpu(dlen);
1643
1644 #if (PAGE_CACHE_SIZE >= 65536)
1645         if (len == EXT4_MAX_REC_LEN || len == 0)
1646                 return blocksize;
1647         return (len & 65532) | ((len & 3) << 16);
1648 #else
1649         return len;
1650 #endif
1651 }
1652
1653 static inline __le16 ext4_rec_len_to_disk(unsigned len, unsigned blocksize)
1654 {
1655         if ((len > blocksize) || (blocksize > (1 << 18)) || (len & 3))
1656                 BUG();
1657 #if (PAGE_CACHE_SIZE >= 65536)
1658         if (len < 65536)
1659                 return cpu_to_le16(len);
1660         if (len == blocksize) {
1661                 if (blocksize == 65536)
1662                         return cpu_to_le16(EXT4_MAX_REC_LEN);
1663                 else
1664                         return cpu_to_le16(0);
1665         }
1666         return cpu_to_le16((len & 65532) | ((len >> 16) & 3));
1667 #else
1668         return cpu_to_le16(len);
1669 #endif
1670 }
1671
1672 /*
1673  * Hash Tree Directory indexing
1674  * (c) Daniel Phillips, 2001
1675  */
1676
1677 #define is_dx(dir) (EXT4_HAS_COMPAT_FEATURE(dir->i_sb, \
1678                                       EXT4_FEATURE_COMPAT_DIR_INDEX) && \
1679                     ext4_test_inode_flag((dir), EXT4_INODE_INDEX))
1680 #define EXT4_DIR_LINK_MAX(dir) (!is_dx(dir) && (dir)->i_nlink >= EXT4_LINK_MAX)
1681 #define EXT4_DIR_LINK_EMPTY(dir) ((dir)->i_nlink == 2 || (dir)->i_nlink == 1)
1682
1683 /* Legal values for the dx_root hash_version field: */
1684
1685 #define DX_HASH_LEGACY          0
1686 #define DX_HASH_HALF_MD4        1
1687 #define DX_HASH_TEA             2
1688 #define DX_HASH_LEGACY_UNSIGNED 3
1689 #define DX_HASH_HALF_MD4_UNSIGNED       4
1690 #define DX_HASH_TEA_UNSIGNED            5
1691
1692 static inline u32 ext4_chksum(struct ext4_sb_info *sbi, u32 crc,
1693                               const void *address, unsigned int length)
1694 {
1695         struct {
1696                 struct shash_desc shash;
1697                 char ctx[4];
1698         } desc;
1699         int err;
1700
1701         BUG_ON(crypto_shash_descsize(sbi->s_chksum_driver)!=sizeof(desc.ctx));
1702
1703         desc.shash.tfm = sbi->s_chksum_driver;
1704         desc.shash.flags = 0;
1705         *(u32 *)desc.ctx = crc;
1706
1707         err = crypto_shash_update(&desc.shash, address, length);
1708         BUG_ON(err);
1709
1710         return *(u32 *)desc.ctx;
1711 }
1712
1713 #ifdef __KERNEL__
1714
1715 /* hash info structure used by the directory hash */
1716 struct dx_hash_info
1717 {
1718         u32             hash;
1719         u32             minor_hash;
1720         int             hash_version;
1721         u32             *seed;
1722 };
1723
1724
1725 /* 32 and 64 bit signed EOF for dx directories */
1726 #define EXT4_HTREE_EOF_32BIT   ((1UL  << (32 - 1)) - 1)
1727 #define EXT4_HTREE_EOF_64BIT   ((1ULL << (64 - 1)) - 1)
1728
1729
1730 /*
1731  * Control parameters used by ext4_htree_next_block
1732  */
1733 #define HASH_NB_ALWAYS          1
1734
1735
1736 /*
1737  * Describe an inode's exact location on disk and in memory
1738  */
1739 struct ext4_iloc
1740 {
1741         struct buffer_head *bh;
1742         unsigned long offset;
1743         ext4_group_t block_group;
1744 };
1745
1746 static inline struct ext4_inode *ext4_raw_inode(struct ext4_iloc *iloc)
1747 {
1748         return (struct ext4_inode *) (iloc->bh->b_data + iloc->offset);
1749 }
1750
1751 /*
1752  * This structure is stuffed into the struct file's private_data field
1753  * for directories.  It is where we put information so that we can do
1754  * readdir operations in hash tree order.
1755  */
1756 struct dir_private_info {
1757         struct rb_root  root;
1758         struct rb_node  *curr_node;
1759         struct fname    *extra_fname;
1760         loff_t          last_pos;
1761         __u32           curr_hash;
1762         __u32           curr_minor_hash;
1763         __u32           next_hash;
1764 };
1765
1766 /* calculate the first block number of the group */
1767 static inline ext4_fsblk_t
1768 ext4_group_first_block_no(struct super_block *sb, ext4_group_t group_no)
1769 {
1770         return group_no * (ext4_fsblk_t)EXT4_BLOCKS_PER_GROUP(sb) +
1771                 le32_to_cpu(EXT4_SB(sb)->s_es->s_first_data_block);
1772 }
1773
1774 /*
1775  * Special error return code only used by dx_probe() and its callers.
1776  */
1777 #define ERR_BAD_DX_DIR  -75000
1778
1779 void ext4_get_group_no_and_offset(struct super_block *sb, ext4_fsblk_t blocknr,
1780                         ext4_group_t *blockgrpp, ext4_grpblk_t *offsetp);
1781
1782 /*
1783  * Timeout and state flag for lazy initialization inode thread.
1784  */
1785 #define EXT4_DEF_LI_WAIT_MULT                   10
1786 #define EXT4_DEF_LI_MAX_START_DELAY             5
1787 #define EXT4_LAZYINIT_QUIT                      0x0001
1788 #define EXT4_LAZYINIT_RUNNING                   0x0002
1789
1790 /*
1791  * Lazy inode table initialization info
1792  */
1793 struct ext4_lazy_init {
1794         unsigned long           li_state;
1795         struct list_head        li_request_list;
1796         struct mutex            li_list_mtx;
1797 };
1798
1799 struct ext4_li_request {
1800         struct super_block      *lr_super;
1801         struct ext4_sb_info     *lr_sbi;
1802         ext4_group_t            lr_next_group;
1803         struct list_head        lr_request;
1804         unsigned long           lr_next_sched;
1805         unsigned long           lr_timeout;
1806 };
1807
1808 struct ext4_features {
1809         struct kobject f_kobj;
1810         struct completion f_kobj_unregister;
1811 };
1812
1813 /*
1814  * This structure will be used for multiple mount protection. It will be
1815  * written into the block number saved in the s_mmp_block field in the
1816  * superblock. Programs that check MMP should assume that if
1817  * SEQ_FSCK (or any unknown code above SEQ_MAX) is present then it is NOT safe
1818  * to use the filesystem, regardless of how old the timestamp is.
1819  */
1820 #define EXT4_MMP_MAGIC     0x004D4D50U /* ASCII for MMP */
1821 #define EXT4_MMP_SEQ_CLEAN 0xFF4D4D50U /* mmp_seq value for clean unmount */
1822 #define EXT4_MMP_SEQ_FSCK  0xE24D4D50U /* mmp_seq value when being fscked */
1823 #define EXT4_MMP_SEQ_MAX   0xE24D4D4FU /* maximum valid mmp_seq value */
1824
1825 struct mmp_struct {
1826         __le32  mmp_magic;              /* Magic number for MMP */
1827         __le32  mmp_seq;                /* Sequence no. updated periodically */
1828
1829         /*
1830          * mmp_time, mmp_nodename & mmp_bdevname are only used for information
1831          * purposes and do not affect the correctness of the algorithm
1832          */
1833         __le64  mmp_time;               /* Time last updated */
1834         char    mmp_nodename[64];       /* Node which last updated MMP block */
1835         char    mmp_bdevname[32];       /* Bdev which last updated MMP block */
1836
1837         /*
1838          * mmp_check_interval is used to verify if the MMP block has been
1839          * updated on the block device. The value is updated based on the
1840          * maximum time to write the MMP block during an update cycle.
1841          */
1842         __le16  mmp_check_interval;
1843
1844         __le16  mmp_pad1;
1845         __le32  mmp_pad2[226];
1846         __le32  mmp_checksum;           /* crc32c(uuid+mmp_block) */
1847 };
1848
1849 /* arguments passed to the mmp thread */
1850 struct mmpd_data {
1851         struct buffer_head *bh; /* bh from initial read_mmp_block() */
1852         struct super_block *sb;  /* super block of the fs */
1853 };
1854
1855 /*
1856  * Check interval multiplier
1857  * The MMP block is written every update interval and initially checked every
1858  * update interval x the multiplier (the value is then adapted based on the
1859  * write latency). The reason is that writes can be delayed under load and we
1860  * don't want readers to incorrectly assume that the filesystem is no longer
1861  * in use.
1862  */
1863 #define EXT4_MMP_CHECK_MULT             2UL
1864
1865 /*
1866  * Minimum interval for MMP checking in seconds.
1867  */
1868 #define EXT4_MMP_MIN_CHECK_INTERVAL     5UL
1869
1870 /*
1871  * Maximum interval for MMP checking in seconds.
1872  */
1873 #define EXT4_MMP_MAX_CHECK_INTERVAL     300UL
1874
1875 /*
1876  * Function prototypes
1877  */
1878
1879 /*
1880  * Ok, these declarations are also in <linux/kernel.h> but none of the
1881  * ext4 source programs needs to include it so they are duplicated here.
1882  */
1883 # define NORET_TYPE     /**/
1884 # define ATTRIB_NORET   __attribute__((noreturn))
1885 # define NORET_AND      noreturn,
1886
1887 /* bitmap.c */
1888 extern unsigned int ext4_count_free(char *bitmap, unsigned numchars);
1889 void ext4_inode_bitmap_csum_set(struct super_block *sb, ext4_group_t group,
1890                                 struct ext4_group_desc *gdp,
1891                                 struct buffer_head *bh, int sz);
1892 int ext4_inode_bitmap_csum_verify(struct super_block *sb, ext4_group_t group,
1893                                   struct ext4_group_desc *gdp,
1894                                   struct buffer_head *bh, int sz);
1895 void ext4_block_bitmap_csum_set(struct super_block *sb, ext4_group_t group,
1896                                 struct ext4_group_desc *gdp,
1897                                 struct buffer_head *bh);
1898 int ext4_block_bitmap_csum_verify(struct super_block *sb, ext4_group_t group,
1899                                   struct ext4_group_desc *gdp,
1900                                   struct buffer_head *bh);
1901
1902 /* balloc.c */
1903 extern void ext4_validate_block_bitmap(struct super_block *sb,
1904                                        struct ext4_group_desc *desc,
1905                                        unsigned int block_group,
1906                                        struct buffer_head *bh);
1907 extern unsigned int ext4_block_group(struct super_block *sb,
1908                         ext4_fsblk_t blocknr);
1909 extern ext4_grpblk_t ext4_block_group_offset(struct super_block *sb,
1910                         ext4_fsblk_t blocknr);
1911 extern int ext4_bg_has_super(struct super_block *sb, ext4_group_t group);
1912 extern unsigned long ext4_bg_num_gdb(struct super_block *sb,
1913                         ext4_group_t group);
1914 extern ext4_fsblk_t ext4_new_meta_blocks(handle_t *handle, struct inode *inode,
1915                                          ext4_fsblk_t goal,
1916                                          unsigned int flags,
1917                                          unsigned long *count,
1918                                          int *errp);
1919 extern int ext4_claim_free_clusters(struct ext4_sb_info *sbi,
1920                                     s64 nclusters, unsigned int flags);
1921 extern ext4_fsblk_t ext4_count_free_clusters(struct super_block *);
1922 extern void ext4_check_blocks_bitmap(struct super_block *);
1923 extern struct ext4_group_desc * ext4_get_group_desc(struct super_block * sb,
1924                                                     ext4_group_t block_group,
1925                                                     struct buffer_head ** bh);
1926 extern int ext4_should_retry_alloc(struct super_block *sb, int *retries);
1927
1928 extern struct buffer_head *ext4_read_block_bitmap_nowait(struct super_block *sb,
1929                                                 ext4_group_t block_group);
1930 extern int ext4_wait_block_bitmap(struct super_block *sb,
1931                                   ext4_group_t block_group,
1932                                   struct buffer_head *bh);
1933 extern struct buffer_head *ext4_read_block_bitmap(struct super_block *sb,
1934                                                   ext4_group_t block_group);
1935 extern void ext4_init_block_bitmap(struct super_block *sb,
1936                                    struct buffer_head *bh,
1937                                    ext4_group_t group,
1938                                    struct ext4_group_desc *desc);
1939 extern unsigned ext4_free_clusters_after_init(struct super_block *sb,
1940                                               ext4_group_t block_group,
1941                                               struct ext4_group_desc *gdp);
1942 extern unsigned ext4_num_overhead_clusters(struct super_block *sb,
1943                                            ext4_group_t block_group,
1944                                            struct ext4_group_desc *gdp);
1945 ext4_fsblk_t ext4_inode_to_goal_block(struct inode *);
1946
1947 /* dir.c */
1948 extern int __ext4_check_dir_entry(const char *, unsigned int, struct inode *,
1949                                   struct file *,
1950                                   struct ext4_dir_entry_2 *,
1951                                   struct buffer_head *, char *, int,
1952                                   unsigned int);
1953 #define ext4_check_dir_entry(dir, filp, de, bh, buf, size, offset)      \
1954         unlikely(__ext4_check_dir_entry(__func__, __LINE__, (dir), (filp), \
1955                                         (de), (bh), (buf), (size), (offset)))
1956 extern int ext4_htree_store_dirent(struct file *dir_file, __u32 hash,
1957                                     __u32 minor_hash,
1958                                     struct ext4_dir_entry_2 *dirent);
1959 extern void ext4_htree_free_dir_info(struct dir_private_info *p);
1960 extern int ext4_find_dest_de(struct inode *dir, struct inode *inode,
1961                              struct buffer_head *bh,
1962                              void *buf, int buf_size,
1963                              const char *name, int namelen,
1964                              struct ext4_dir_entry_2 **dest_de);
1965 void ext4_insert_dentry(struct inode *inode,
1966                         struct ext4_dir_entry_2 *de,
1967                         int buf_size,
1968                         const char *name, int namelen);
1969 static inline void ext4_update_dx_flag(struct inode *inode)
1970 {
1971         if (!EXT4_HAS_COMPAT_FEATURE(inode->i_sb,
1972                                      EXT4_FEATURE_COMPAT_DIR_INDEX))
1973                 ext4_clear_inode_flag(inode, EXT4_INODE_INDEX);
1974 }
1975 static unsigned char ext4_filetype_table[] = {
1976         DT_UNKNOWN, DT_REG, DT_DIR, DT_CHR, DT_BLK, DT_FIFO, DT_SOCK, DT_LNK
1977 };
1978
1979 static inline  unsigned char get_dtype(struct super_block *sb, int filetype)
1980 {
1981         if (!EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_FILETYPE) ||
1982             (filetype >= EXT4_FT_MAX))
1983                 return DT_UNKNOWN;
1984
1985         return ext4_filetype_table[filetype];
1986 }
1987
1988 /* fsync.c */
1989 extern int ext4_sync_file(struct file *, loff_t, loff_t, int);
1990 extern int ext4_flush_unwritten_io(struct inode *);
1991
1992 /* hash.c */
1993 extern int ext4fs_dirhash(const char *name, int len, struct
1994                           dx_hash_info *hinfo);
1995
1996 /* ialloc.c */
1997 extern struct inode *__ext4_new_inode(handle_t *, struct inode *, umode_t,
1998                                       const struct qstr *qstr, __u32 goal,
1999                                       uid_t *owner, int handle_type,
2000                                       unsigned int line_no, int nblocks);
2001
2002 #define ext4_new_inode(handle, dir, mode, qstr, goal, owner) \
2003         __ext4_new_inode((handle), (dir), (mode), (qstr), (goal), (owner), \
2004                          0, 0, 0)
2005 #define ext4_new_inode_start_handle(dir, mode, qstr, goal, owner, \
2006                                     type, nblocks)                  \
2007         __ext4_new_inode(NULL, (dir), (mode), (qstr), (goal), (owner), \
2008                          (type), __LINE__, (nblocks))
2009
2010
2011 extern void ext4_free_inode(handle_t *, struct inode *);
2012 extern struct inode * ext4_orphan_get(struct super_block *, unsigned long);
2013 extern unsigned long ext4_count_free_inodes(struct super_block *);
2014 extern unsigned long ext4_count_dirs(struct super_block *);
2015 extern void ext4_check_inodes_bitmap(struct super_block *);
2016 extern void ext4_mark_bitmap_end(int start_bit, int end_bit, char *bitmap);
2017 extern int ext4_init_inode_table(struct super_block *sb,
2018                                  ext4_group_t group, int barrier);
2019 extern void ext4_end_bitmap_read(struct buffer_head *bh, int uptodate);
2020
2021 /* mballoc.c */
2022 extern long ext4_mb_stats;
2023 extern long ext4_mb_max_to_scan;
2024 extern int ext4_mb_init(struct super_block *);
2025 extern int ext4_mb_release(struct super_block *);
2026 extern ext4_fsblk_t ext4_mb_new_blocks(handle_t *,
2027                                 struct ext4_allocation_request *, int *);
2028 extern int ext4_mb_reserve_blocks(struct super_block *, int);
2029 extern void ext4_discard_preallocations(struct inode *);
2030 extern int __init ext4_init_mballoc(void);
2031 extern void ext4_exit_mballoc(void);
2032 extern void ext4_free_blocks(handle_t *handle, struct inode *inode,
2033                              struct buffer_head *bh, ext4_fsblk_t block,
2034                              unsigned long count, int flags);
2035 extern int ext4_mb_alloc_groupinfo(struct super_block *sb,
2036                                    ext4_group_t ngroups);
2037 extern int ext4_mb_add_groupinfo(struct super_block *sb,
2038                 ext4_group_t i, struct ext4_group_desc *desc);
2039 extern int ext4_group_add_blocks(handle_t *handle, struct super_block *sb,
2040                                 ext4_fsblk_t block, unsigned long count);
2041 extern int ext4_trim_fs(struct super_block *, struct fstrim_range *);
2042
2043 /* inode.c */
2044 struct buffer_head *ext4_getblk(handle_t *, struct inode *,
2045                                                 ext4_lblk_t, int, int *);
2046 struct buffer_head *ext4_bread(handle_t *, struct inode *,
2047                                                 ext4_lblk_t, int, int *);
2048 int ext4_get_block_write(struct inode *inode, sector_t iblock,
2049                          struct buffer_head *bh_result, int create);
2050 int ext4_get_block(struct inode *inode, sector_t iblock,
2051                                 struct buffer_head *bh_result, int create);
2052 int ext4_da_get_block_prep(struct inode *inode, sector_t iblock,
2053                            struct buffer_head *bh, int create);
2054 int ext4_walk_page_buffers(handle_t *handle,
2055                            struct buffer_head *head,
2056                            unsigned from,
2057                            unsigned to,
2058                            int *partial,
2059                            int (*fn)(handle_t *handle,
2060                                      struct buffer_head *bh));
2061 int do_journal_get_write_access(handle_t *handle,
2062                                 struct buffer_head *bh);
2063 #define FALL_BACK_TO_NONDELALLOC 1
2064 #define CONVERT_INLINE_DATA      2
2065
2066 extern struct inode *ext4_iget(struct super_block *, unsigned long);
2067 extern int  ext4_write_inode(struct inode *, struct writeback_control *);
2068 extern int  ext4_setattr(struct dentry *, struct iattr *);
2069 extern int  ext4_getattr(struct vfsmount *mnt, struct dentry *dentry,
2070                                 struct kstat *stat);
2071 extern void ext4_evict_inode(struct inode *);
2072 extern void ext4_clear_inode(struct inode *);
2073 extern int  ext4_sync_inode(handle_t *, struct inode *);
2074 extern void ext4_dirty_inode(struct inode *, int);
2075 extern int ext4_change_inode_journal_flag(struct inode *, int);
2076 extern int ext4_get_inode_loc(struct inode *, struct ext4_iloc *);
2077 extern int ext4_can_truncate(struct inode *inode);
2078 extern void ext4_truncate(struct inode *);
2079 extern int ext4_punch_hole(struct file *file, loff_t offset, loff_t length);
2080 extern int ext4_truncate_restart_trans(handle_t *, struct inode *, int nblocks);
2081 extern void ext4_set_inode_flags(struct inode *);
2082 extern void ext4_get_inode_flags(struct ext4_inode_info *);
2083 extern int ext4_alloc_da_blocks(struct inode *inode);
2084 extern void ext4_set_aops(struct inode *inode);
2085 extern int ext4_writepage_trans_blocks(struct inode *);
2086 extern int ext4_chunk_trans_blocks(struct inode *, int nrblocks);
2087 extern int ext4_discard_partial_page_buffers(handle_t *handle,
2088                 struct address_space *mapping, loff_t from,
2089                 loff_t length, int flags);
2090 extern int ext4_page_mkwrite(struct vm_area_struct *vma, struct vm_fault *vmf);
2091 extern qsize_t *ext4_get_reserved_space(struct inode *inode);
2092 extern void ext4_da_update_reserve_space(struct inode *inode,
2093                                         int used, int quota_claim);
2094
2095 /* indirect.c */
2096 extern int ext4_ind_map_blocks(handle_t *handle, struct inode *inode,
2097                                 struct ext4_map_blocks *map, int flags);
2098 extern ssize_t ext4_ind_direct_IO(int rw, struct kiocb *iocb,
2099                                 const struct iovec *iov, loff_t offset,
2100                                 unsigned long nr_segs);
2101 extern int ext4_ind_calc_metadata_amount(struct inode *inode, sector_t lblock);
2102 extern int ext4_ind_trans_blocks(struct inode *inode, int nrblocks, int chunk);
2103 extern void ext4_ind_truncate(struct inode *inode);
2104 extern int ext4_ind_punch_hole(struct file *file, loff_t offset, loff_t length);
2105
2106 /* ioctl.c */
2107 extern long ext4_ioctl(struct file *, unsigned int, unsigned long);
2108 extern long ext4_compat_ioctl(struct file *, unsigned int, unsigned long);
2109
2110 /* migrate.c */
2111 extern int ext4_ext_migrate(struct inode *);
2112
2113 /* namei.c */
2114 extern int ext4_dirent_csum_verify(struct inode *inode,
2115                                    struct ext4_dir_entry *dirent);
2116 extern int ext4_orphan_add(handle_t *, struct inode *);
2117 extern int ext4_orphan_del(handle_t *, struct inode *);
2118 extern int ext4_htree_fill_tree(struct file *dir_file, __u32 start_hash,
2119                                 __u32 start_minor_hash, __u32 *next_hash);
2120 extern int search_dir(struct buffer_head *bh,
2121                       char *search_buf,
2122                       int buf_size,
2123                       struct inode *dir,
2124                       const struct qstr *d_name,
2125                       unsigned int offset,
2126                       struct ext4_dir_entry_2 **res_dir);
2127 extern int ext4_generic_delete_entry(handle_t *handle,
2128                                      struct inode *dir,
2129                                      struct ext4_dir_entry_2 *de_del,
2130                                      struct buffer_head *bh,
2131                                      void *entry_buf,
2132                                      int buf_size,
2133                                      int csum_size);
2134
2135 /* resize.c */
2136 extern int ext4_group_add(struct super_block *sb,
2137                                 struct ext4_new_group_data *input);
2138 extern int ext4_group_extend(struct super_block *sb,
2139                                 struct ext4_super_block *es,
2140                                 ext4_fsblk_t n_blocks_count);
2141 extern int ext4_resize_fs(struct super_block *sb, ext4_fsblk_t n_blocks_count);
2142
2143 /* super.c */
2144 extern int ext4_calculate_overhead(struct super_block *sb);
2145 extern int ext4_superblock_csum_verify(struct super_block *sb,
2146                                        struct ext4_super_block *es);
2147 extern void ext4_superblock_csum_set(struct super_block *sb);
2148 extern void *ext4_kvmalloc(size_t size, gfp_t flags);
2149 extern void *ext4_kvzalloc(size_t size, gfp_t flags);
2150 extern void ext4_kvfree(void *ptr);
2151 extern int ext4_alloc_flex_bg_array(struct super_block *sb,
2152                                     ext4_group_t ngroup);
2153 extern const char *ext4_decode_error(struct super_block *sb, int errno,
2154                                      char nbuf[16]);
2155 extern __printf(4, 5)
2156 void __ext4_error(struct super_block *, const char *, unsigned int,
2157                   const char *, ...);
2158 #define ext4_error(sb, message...)      __ext4_error(sb, __func__,      \
2159                                                      __LINE__, ## message)
2160 extern __printf(5, 6)
2161 void ext4_error_inode(struct inode *, const char *, unsigned int, ext4_fsblk_t,
2162                       const char *, ...);
2163 extern __printf(5, 6)
2164 void ext4_error_file(struct file *, const char *, unsigned int, ext4_fsblk_t,
2165                      const char *, ...);
2166 extern void __ext4_std_error(struct super_block *, const char *,
2167                              unsigned int, int);
2168 extern __printf(4, 5)
2169 void __ext4_abort(struct super_block *, const char *, unsigned int,
2170                   const char *, ...);
2171 #define ext4_abort(sb, message...)      __ext4_abort(sb, __func__, \
2172                                                        __LINE__, ## message)
2173 extern __printf(4, 5)
2174 void __ext4_warning(struct super_block *, const char *, unsigned int,
2175                     const char *, ...);
2176 #define ext4_warning(sb, message...)    __ext4_warning(sb, __func__, \
2177                                                        __LINE__, ## message)
2178 extern __printf(3, 4)
2179 void ext4_msg(struct super_block *, const char *, const char *, ...);
2180 extern void __dump_mmp_msg(struct super_block *, struct mmp_struct *mmp,
2181                            const char *, unsigned int, const char *);
2182 #define dump_mmp_msg(sb, mmp, msg)      __dump_mmp_msg(sb, mmp, __func__, \
2183                                                        __LINE__, msg)
2184 extern __printf(7, 8)
2185 void __ext4_grp_locked_error(const char *, unsigned int,
2186                              struct super_block *, ext4_group_t,
2187                              unsigned long, ext4_fsblk_t,
2188                              const char *, ...);
2189 #define ext4_grp_locked_error(sb, grp, message...) \
2190         __ext4_grp_locked_error(__func__, __LINE__, (sb), (grp), ## message)
2191 extern void ext4_update_dynamic_rev(struct super_block *sb);
2192 extern int ext4_update_compat_feature(handle_t *handle, struct super_block *sb,
2193                                         __u32 compat);
2194 extern int ext4_update_rocompat_feature(handle_t *handle,
2195                                         struct super_block *sb, __u32 rocompat);
2196 extern int ext4_update_incompat_feature(handle_t *handle,
2197                                         struct super_block *sb, __u32 incompat);
2198 extern ext4_fsblk_t ext4_block_bitmap(struct super_block *sb,
2199                                       struct ext4_group_desc *bg);
2200 extern ext4_fsblk_t ext4_inode_bitmap(struct super_block *sb,
2201                                       struct ext4_group_desc *bg);
2202 extern ext4_fsblk_t ext4_inode_table(struct super_block *sb,
2203                                      struct ext4_group_desc *bg);
2204 extern __u32 ext4_free_group_clusters(struct super_block *sb,
2205                                       struct ext4_group_desc *bg);
2206 extern __u32 ext4_free_inodes_count(struct super_block *sb,
2207                                  struct ext4_group_desc *bg);
2208 extern __u32 ext4_used_dirs_count(struct super_block *sb,
2209                                 struct ext4_group_desc *bg);
2210 extern __u32 ext4_itable_unused_count(struct super_block *sb,
2211                                    struct ext4_group_desc *bg);
2212 extern void ext4_block_bitmap_set(struct super_block *sb,
2213                                   struct ext4_group_desc *bg, ext4_fsblk_t blk);
2214 extern void ext4_inode_bitmap_set(struct super_block *sb,
2215                                   struct ext4_group_desc *bg, ext4_fsblk_t blk);
2216 extern void ext4_inode_table_set(struct super_block *sb,
2217                                  struct ext4_group_desc *bg, ext4_fsblk_t blk);
2218 extern void ext4_free_group_clusters_set(struct super_block *sb,
2219                                          struct ext4_group_desc *bg,
2220                                          __u32 count);
2221 extern void ext4_free_inodes_set(struct super_block *sb,
2222                                 struct ext4_group_desc *bg, __u32 count);
2223 extern void ext4_used_dirs_set(struct super_block *sb,
2224                                 struct ext4_group_desc *bg, __u32 count);
2225 extern void ext4_itable_unused_set(struct super_block *sb,
2226                                    struct ext4_group_desc *bg, __u32 count);
2227 extern int ext4_group_desc_csum_verify(struct super_block *sb, __u32 group,
2228                                        struct ext4_group_desc *gdp);
2229 extern void ext4_group_desc_csum_set(struct super_block *sb, __u32 group,
2230                                      struct ext4_group_desc *gdp);
2231 extern int ext4_register_li_request(struct super_block *sb,
2232                                     ext4_group_t first_not_zeroed);
2233
2234 static inline int ext4_has_group_desc_csum(struct super_block *sb)
2235 {
2236         return EXT4_HAS_RO_COMPAT_FEATURE(sb,
2237                                           EXT4_FEATURE_RO_COMPAT_GDT_CSUM |
2238                                           EXT4_FEATURE_RO_COMPAT_METADATA_CSUM);
2239 }
2240
2241 static inline ext4_fsblk_t ext4_blocks_count(struct ext4_super_block *es)
2242 {
2243         return ((ext4_fsblk_t)le32_to_cpu(es->s_blocks_count_hi) << 32) |
2244                 le32_to_cpu(es->s_blocks_count_lo);
2245 }
2246
2247 static inline ext4_fsblk_t ext4_r_blocks_count(struct ext4_super_block *es)
2248 {
2249         return ((ext4_fsblk_t)le32_to_cpu(es->s_r_blocks_count_hi) << 32) |
2250                 le32_to_cpu(es->s_r_blocks_count_lo);
2251 }
2252
2253 static inline ext4_fsblk_t ext4_free_blocks_count(struct ext4_super_block *es)
2254 {
2255         return ((ext4_fsblk_t)le32_to_cpu(es->s_free_blocks_count_hi) << 32) |
2256                 le32_to_cpu(es->s_free_blocks_count_lo);
2257 }
2258
2259 static inline void ext4_blocks_count_set(struct ext4_super_block *es,
2260                                          ext4_fsblk_t blk)
2261 {
2262         es->s_blocks_count_lo = cpu_to_le32((u32)blk);
2263         es->s_blocks_count_hi = cpu_to_le32(blk >> 32);
2264 }
2265
2266 static inline void ext4_free_blocks_count_set(struct ext4_super_block *es,
2267                                               ext4_fsblk_t blk)
2268 {
2269         es->s_free_blocks_count_lo = cpu_to_le32((u32)blk);
2270         es->s_free_blocks_count_hi = cpu_to_le32(blk >> 32);
2271 }
2272
2273 static inline void ext4_r_blocks_count_set(struct ext4_super_block *es,
2274                                            ext4_fsblk_t blk)
2275 {
2276         es->s_r_blocks_count_lo = cpu_to_le32((u32)blk);
2277         es->s_r_blocks_count_hi = cpu_to_le32(blk >> 32);
2278 }
2279
2280 static inline loff_t ext4_isize(struct ext4_inode *raw_inode)
2281 {
2282         if (S_ISREG(le16_to_cpu(raw_inode->i_mode)))
2283                 return ((loff_t)le32_to_cpu(raw_inode->i_size_high) << 32) |
2284                         le32_to_cpu(raw_inode->i_size_lo);
2285         else
2286                 return (loff_t) le32_to_cpu(raw_inode->i_size_lo);
2287 }
2288
2289 static inline void ext4_isize_set(struct ext4_inode *raw_inode, loff_t i_size)
2290 {
2291         raw_inode->i_size_lo = cpu_to_le32(i_size);
2292         raw_inode->i_size_high = cpu_to_le32(i_size >> 32);
2293 }
2294
2295 static inline
2296 struct ext4_group_info *ext4_get_group_info(struct super_block *sb,
2297                                             ext4_group_t group)
2298 {
2299          struct ext4_group_info ***grp_info;
2300          long indexv, indexh;
2301          grp_info = EXT4_SB(sb)->s_group_info;
2302          indexv = group >> (EXT4_DESC_PER_BLOCK_BITS(sb));
2303          indexh = group & ((EXT4_DESC_PER_BLOCK(sb)) - 1);
2304          return grp_info[indexv][indexh];
2305 }
2306
2307 /*
2308  * Reading s_groups_count requires using smp_rmb() afterwards.  See
2309  * the locking protocol documented in the comments of ext4_group_add()
2310  * in resize.c
2311  */
2312 static inline ext4_group_t ext4_get_groups_count(struct super_block *sb)
2313 {
2314         ext4_group_t    ngroups = EXT4_SB(sb)->s_groups_count;
2315
2316         smp_rmb();
2317         return ngroups;
2318 }
2319
2320 static inline ext4_group_t ext4_flex_group(struct ext4_sb_info *sbi,
2321                                              ext4_group_t block_group)
2322 {
2323         return block_group >> sbi->s_log_groups_per_flex;
2324 }
2325
2326 static inline unsigned int ext4_flex_bg_size(struct ext4_sb_info *sbi)
2327 {
2328         return 1 << sbi->s_log_groups_per_flex;
2329 }
2330
2331 #define ext4_std_error(sb, errno)                               \
2332 do {                                                            \
2333         if ((errno))                                            \
2334                 __ext4_std_error((sb), __func__, __LINE__, (errno));    \
2335 } while (0)
2336
2337 #ifdef CONFIG_SMP
2338 /* Each CPU can accumulate percpu_counter_batch clusters in their local
2339  * counters. So we need to make sure we have free clusters more
2340  * than percpu_counter_batch  * nr_cpu_ids. Also add a window of 4 times.
2341  */
2342 #define EXT4_FREECLUSTERS_WATERMARK (4 * (percpu_counter_batch * nr_cpu_ids))
2343 #else
2344 #define EXT4_FREECLUSTERS_WATERMARK 0
2345 #endif
2346
2347 static inline void ext4_update_i_disksize(struct inode *inode, loff_t newsize)
2348 {
2349         /*
2350          * XXX: replace with spinlock if seen contended -bzzz
2351          */
2352         down_write(&EXT4_I(inode)->i_data_sem);
2353         if (newsize > EXT4_I(inode)->i_disksize)
2354                 EXT4_I(inode)->i_disksize = newsize;
2355         up_write(&EXT4_I(inode)->i_data_sem);
2356         return ;
2357 }
2358
2359 struct ext4_group_info {
2360         unsigned long   bb_state;
2361         struct rb_root  bb_free_root;
2362         ext4_grpblk_t   bb_first_free;  /* first free block */
2363         ext4_grpblk_t   bb_free;        /* total free blocks */
2364         ext4_grpblk_t   bb_fragments;   /* nr of freespace fragments */
2365         ext4_grpblk_t   bb_largest_free_order;/* order of largest frag in BG */
2366         struct          list_head bb_prealloc_list;
2367 #ifdef DOUBLE_CHECK
2368         void            *bb_bitmap;
2369 #endif
2370         struct rw_semaphore alloc_sem;
2371         ext4_grpblk_t   bb_counters[];  /* Nr of free power-of-two-block
2372                                          * regions, index is order.
2373                                          * bb_counters[3] = 5 means
2374                                          * 5 free 8-block regions. */
2375 };
2376
2377 #define EXT4_GROUP_INFO_NEED_INIT_BIT           0
2378 #define EXT4_GROUP_INFO_WAS_TRIMMED_BIT         1
2379
2380 #define EXT4_MB_GRP_NEED_INIT(grp)      \
2381         (test_bit(EXT4_GROUP_INFO_NEED_INIT_BIT, &((grp)->bb_state)))
2382
2383 #define EXT4_MB_GRP_WAS_TRIMMED(grp)    \
2384         (test_bit(EXT4_GROUP_INFO_WAS_TRIMMED_BIT, &((grp)->bb_state)))
2385 #define EXT4_MB_GRP_SET_TRIMMED(grp)    \
2386         (set_bit(EXT4_GROUP_INFO_WAS_TRIMMED_BIT, &((grp)->bb_state)))
2387 #define EXT4_MB_GRP_CLEAR_TRIMMED(grp)  \
2388         (clear_bit(EXT4_GROUP_INFO_WAS_TRIMMED_BIT, &((grp)->bb_state)))
2389
2390 #define EXT4_MAX_CONTENTION             8
2391 #define EXT4_CONTENTION_THRESHOLD       2
2392
2393 static inline spinlock_t *ext4_group_lock_ptr(struct super_block *sb,
2394                                               ext4_group_t group)
2395 {
2396         return bgl_lock_ptr(EXT4_SB(sb)->s_blockgroup_lock, group);
2397 }
2398
2399 /*
2400  * Returns true if the filesystem is busy enough that attempts to
2401  * access the block group locks has run into contention.
2402  */
2403 static inline int ext4_fs_is_busy(struct ext4_sb_info *sbi)
2404 {
2405         return (atomic_read(&sbi->s_lock_busy) > EXT4_CONTENTION_THRESHOLD);
2406 }
2407
2408 static inline void ext4_lock_group(struct super_block *sb, ext4_group_t group)
2409 {
2410         spinlock_t *lock = ext4_group_lock_ptr(sb, group);
2411         if (spin_trylock(lock))
2412                 /*
2413                  * We're able to grab the lock right away, so drop the
2414                  * lock contention counter.
2415                  */
2416                 atomic_add_unless(&EXT4_SB(sb)->s_lock_busy, -1, 0);
2417         else {
2418                 /*
2419                  * The lock is busy, so bump the contention counter,
2420                  * and then wait on the spin lock.
2421                  */
2422                 atomic_add_unless(&EXT4_SB(sb)->s_lock_busy, 1,
2423                                   EXT4_MAX_CONTENTION);
2424                 spin_lock(lock);
2425         }
2426 }
2427
2428 static inline void ext4_unlock_group(struct super_block *sb,
2429                                         ext4_group_t group)
2430 {
2431         spin_unlock(ext4_group_lock_ptr(sb, group));
2432 }
2433
2434 /*
2435  * Block validity checking
2436  */
2437 #define ext4_check_indirect_blockref(inode, bh)                         \
2438         ext4_check_blockref(__func__, __LINE__, inode,                  \
2439                             (__le32 *)(bh)->b_data,                     \
2440                             EXT4_ADDR_PER_BLOCK((inode)->i_sb))
2441
2442 #define ext4_ind_check_inode(inode)                                     \
2443         ext4_check_blockref(__func__, __LINE__, inode,                  \
2444                             EXT4_I(inode)->i_data,                      \
2445                             EXT4_NDIR_BLOCKS)
2446
2447 /*
2448  * Inodes and files operations
2449  */
2450
2451 /* dir.c */
2452 extern const struct file_operations ext4_dir_operations;
2453
2454 /* file.c */
2455 extern const struct inode_operations ext4_file_inode_operations;
2456 extern const struct file_operations ext4_file_operations;
2457 extern loff_t ext4_llseek(struct file *file, loff_t offset, int origin);
2458 extern void ext4_unwritten_wait(struct inode *inode);
2459
2460 /* inline.c */
2461 extern int ext4_has_inline_data(struct inode *inode);
2462 extern int ext4_get_inline_size(struct inode *inode);
2463 extern int ext4_get_max_inline_size(struct inode *inode);
2464 extern int ext4_find_inline_data_nolock(struct inode *inode);
2465 extern void ext4_write_inline_data(struct inode *inode,
2466                                    struct ext4_iloc *iloc,
2467                                    void *buffer, loff_t pos,
2468                                    unsigned int len);
2469 extern int ext4_prepare_inline_data(handle_t *handle, struct inode *inode,
2470                                     unsigned int len);
2471 extern int ext4_init_inline_data(handle_t *handle, struct inode *inode,
2472                                  unsigned int len);
2473 extern int ext4_destroy_inline_data(handle_t *handle, struct inode *inode);
2474
2475 extern int ext4_readpage_inline(struct inode *inode, struct page *page);
2476 extern int ext4_try_to_write_inline_data(struct address_space *mapping,
2477                                          struct inode *inode,
2478                                          loff_t pos, unsigned len,
2479                                          unsigned flags,
2480                                          struct page **pagep);
2481 extern int ext4_write_inline_data_end(struct inode *inode,
2482                                       loff_t pos, unsigned len,
2483                                       unsigned copied,
2484                                       struct page *page);
2485 extern struct buffer_head *
2486 ext4_journalled_write_inline_data(struct inode *inode,
2487                                   unsigned len,
2488                                   struct page *page);
2489 extern int ext4_da_write_inline_data_begin(struct address_space *mapping,
2490                                            struct inode *inode,
2491                                            loff_t pos, unsigned len,
2492                                            unsigned flags,
2493                                            struct page **pagep,
2494                                            void **fsdata);
2495 extern int ext4_da_write_inline_data_end(struct inode *inode, loff_t pos,
2496                                          unsigned len, unsigned copied,
2497                                          struct page *page);
2498 extern int ext4_try_add_inline_entry(handle_t *handle, struct dentry *dentry,
2499                                      struct inode *inode);
2500 extern int ext4_try_create_inline_dir(handle_t *handle,
2501                                       struct inode *parent,
2502                                       struct inode *inode);
2503 extern int ext4_read_inline_dir(struct file *filp,
2504                                 void *dirent, filldir_t filldir,
2505                                 int *has_inline_data);
2506 extern struct buffer_head *ext4_find_inline_entry(struct inode *dir,
2507                                         const struct qstr *d_name,
2508                                         struct ext4_dir_entry_2 **res_dir,
2509                                         int *has_inline_data);
2510 extern int ext4_delete_inline_entry(handle_t *handle,
2511                                     struct inode *dir,
2512                                     struct ext4_dir_entry_2 *de_del,
2513                                     struct buffer_head *bh,
2514                                     int *has_inline_data);
2515 extern int empty_inline_dir(struct inode *dir, int *has_inline_data);
2516 extern struct buffer_head *ext4_get_first_inline_block(struct inode *inode,
2517                                         struct ext4_dir_entry_2 **parent_de,
2518                                         int *retval);
2519 extern int ext4_inline_data_fiemap(struct inode *inode,
2520                                    struct fiemap_extent_info *fieinfo,
2521                                    int *has_inline);
2522 extern int ext4_try_to_evict_inline_data(handle_t *handle,
2523                                          struct inode *inode,
2524                                          int needed);
2525 extern void ext4_inline_data_truncate(struct inode *inode, int *has_inline);
2526
2527 extern int ext4_convert_inline_data(struct inode *inode);
2528
2529 /* namei.c */
2530 extern const struct inode_operations ext4_dir_inode_operations;
2531 extern const struct inode_operations ext4_special_inode_operations;
2532 extern struct dentry *ext4_get_parent(struct dentry *child);
2533 extern struct ext4_dir_entry_2 *ext4_init_dot_dotdot(struct inode *inode,
2534                                  struct ext4_dir_entry_2 *de,
2535                                  int blocksize, int csum_size,
2536                                  unsigned int parent_ino, int dotdot_real_len);
2537 extern void initialize_dirent_tail(struct ext4_dir_entry_tail *t,
2538                                    unsigned int blocksize);
2539 extern int ext4_handle_dirty_dirent_node(handle_t *handle,
2540                                          struct inode *inode,
2541                                          struct buffer_head *bh);
2542
2543 /* symlink.c */
2544 extern const struct inode_operations ext4_symlink_inode_operations;
2545 extern const struct inode_operations ext4_fast_symlink_inode_operations;
2546
2547 /* block_validity */
2548 extern void ext4_release_system_zone(struct super_block *sb);
2549 extern int ext4_setup_system_zone(struct super_block *sb);
2550 extern int __init ext4_init_system_zone(void);
2551 extern void ext4_exit_system_zone(void);
2552 extern int ext4_data_block_valid(struct ext4_sb_info *sbi,
2553                                  ext4_fsblk_t start_blk,
2554                                  unsigned int count);
2555 extern int ext4_check_blockref(const char *, unsigned int,
2556                                struct inode *, __le32 *, unsigned int);
2557
2558 /* extents.c */
2559 struct ext4_ext_path;
2560 struct ext4_extent;
2561
2562 extern int ext4_ext_tree_init(handle_t *handle, struct inode *);
2563 extern int ext4_ext_writepage_trans_blocks(struct inode *, int);
2564 extern int ext4_ext_index_trans_blocks(struct inode *inode, int nrblocks,
2565                                        int chunk);
2566 extern int ext4_ext_map_blocks(handle_t *handle, struct inode *inode,
2567                                struct ext4_map_blocks *map, int flags);
2568 extern void ext4_ext_truncate(struct inode *);
2569 extern int ext4_ext_punch_hole(struct file *file, loff_t offset,
2570                                 loff_t length);
2571 extern void ext4_ext_init(struct super_block *);
2572 extern void ext4_ext_release(struct super_block *);
2573 extern long ext4_fallocate(struct file *file, int mode, loff_t offset,
2574                           loff_t len);
2575 extern int ext4_convert_unwritten_extents(struct inode *inode, loff_t offset,
2576                           ssize_t len);
2577 extern int ext4_map_blocks(handle_t *handle, struct inode *inode,
2578                            struct ext4_map_blocks *map, int flags);
2579 extern int ext4_ext_calc_metadata_amount(struct inode *inode,
2580                                          ext4_lblk_t lblocks);
2581 extern int ext4_extent_tree_init(handle_t *, struct inode *);
2582 extern int ext4_ext_calc_credits_for_single_extent(struct inode *inode,
2583                                                    int num,
2584                                                    struct ext4_ext_path *path);
2585 extern int ext4_can_extents_be_merged(struct inode *inode,
2586                                       struct ext4_extent *ex1,
2587                                       struct ext4_extent *ex2);
2588 extern int ext4_ext_insert_extent(handle_t *, struct inode *,
2589                                   struct ext4_ext_path *,
2590                                   struct ext4_extent *, int);
2591 extern struct ext4_ext_path *ext4_ext_find_extent(struct inode *, ext4_lblk_t,
2592                                                   struct ext4_ext_path *);
2593 extern void ext4_ext_drop_refs(struct ext4_ext_path *);
2594 extern int ext4_ext_check_inode(struct inode *inode);
2595 extern int ext4_find_delalloc_range(struct inode *inode,
2596                                     ext4_lblk_t lblk_start,
2597                                     ext4_lblk_t lblk_end);
2598 extern int ext4_find_delalloc_cluster(struct inode *inode, ext4_lblk_t lblk);
2599 extern int ext4_fiemap(struct inode *inode, struct fiemap_extent_info *fieinfo,
2600                         __u64 start, __u64 len);
2601
2602
2603 /* move_extent.c */
2604 extern int ext4_move_extents(struct file *o_filp, struct file *d_filp,
2605                              __u64 start_orig, __u64 start_donor,
2606                              __u64 len, __u64 *moved_len);
2607
2608 /* page-io.c */
2609 extern int __init ext4_init_pageio(void);
2610 extern void ext4_add_complete_io(ext4_io_end_t *io_end);
2611 extern void ext4_exit_pageio(void);
2612 extern void ext4_ioend_wait(struct inode *);
2613 extern void ext4_free_io_end(ext4_io_end_t *io);
2614 extern ext4_io_end_t *ext4_init_io_end(struct inode *inode, gfp_t flags);
2615 extern void ext4_end_io_work(struct work_struct *work);
2616 extern void ext4_io_submit(struct ext4_io_submit *io);
2617 extern int ext4_bio_write_page(struct ext4_io_submit *io,
2618                                struct page *page,
2619                                int len,
2620                                struct writeback_control *wbc);
2621
2622 /* mmp.c */
2623 extern int ext4_multi_mount_protect(struct super_block *, ext4_fsblk_t);
2624 extern void ext4_mmp_csum_set(struct super_block *sb, struct mmp_struct *mmp);
2625 extern int ext4_mmp_csum_verify(struct super_block *sb,
2626                                 struct mmp_struct *mmp);
2627
2628 /* BH_Uninit flag: blocks are allocated but uninitialized on disk */
2629 enum ext4_state_bits {
2630         BH_Uninit       /* blocks are allocated but uninitialized on disk */
2631           = BH_JBDPrivateStart,
2632         BH_AllocFromCluster,    /* allocated blocks were part of already
2633                                  * allocated cluster. Note that this flag will
2634                                  * never, ever appear in a buffer_head's state
2635                                  * flag. See EXT4_MAP_FROM_CLUSTER to see where
2636                                  * this is used. */
2637 };
2638
2639 BUFFER_FNS(Uninit, uninit)
2640 TAS_BUFFER_FNS(Uninit, uninit)
2641
2642 /*
2643  * Add new method to test whether block and inode bitmaps are properly
2644  * initialized. With uninit_bg reading the block from disk is not enough
2645  * to mark the bitmap uptodate. We need to also zero-out the bitmap
2646  */
2647 #define BH_BITMAP_UPTODATE BH_JBDPrivateStart
2648
2649 static inline int bitmap_uptodate(struct buffer_head *bh)
2650 {
2651         return (buffer_uptodate(bh) &&
2652                         test_bit(BH_BITMAP_UPTODATE, &(bh)->b_state));
2653 }
2654 static inline void set_bitmap_uptodate(struct buffer_head *bh)
2655 {
2656         set_bit(BH_BITMAP_UPTODATE, &(bh)->b_state);
2657 }
2658
2659 /*
2660  * Disable DIO read nolock optimization, so new dioreaders will be forced
2661  * to grab i_mutex
2662  */
2663 static inline void ext4_inode_block_unlocked_dio(struct inode *inode)
2664 {
2665         ext4_set_inode_state(inode, EXT4_STATE_DIOREAD_LOCK);
2666         smp_mb();
2667 }
2668 static inline void ext4_inode_resume_unlocked_dio(struct inode *inode)
2669 {
2670         smp_mb();
2671         ext4_clear_inode_state(inode, EXT4_STATE_DIOREAD_LOCK);
2672 }
2673
2674 #define in_range(b, first, len) ((b) >= (first) && (b) <= (first) + (len) - 1)
2675
2676 /* For ioend & aio unwritten conversion wait queues */
2677 #define EXT4_WQ_HASH_SZ         37
2678 #define ext4_ioend_wq(v)   (&ext4__ioend_wq[((unsigned long)(v)) %\
2679                                             EXT4_WQ_HASH_SZ])
2680 #define ext4_aio_mutex(v)  (&ext4__aio_mutex[((unsigned long)(v)) %\
2681                                              EXT4_WQ_HASH_SZ])
2682 extern wait_queue_head_t ext4__ioend_wq[EXT4_WQ_HASH_SZ];
2683 extern struct mutex ext4__aio_mutex[EXT4_WQ_HASH_SZ];
2684
2685 #define EXT4_RESIZING   0
2686 extern int ext4_resize_begin(struct super_block *sb);
2687 extern void ext4_resize_end(struct super_block *sb);
2688
2689 #endif  /* __KERNEL__ */
2690
2691 #endif  /* _EXT4_H */