Pileus Git - ~andy/linux/blob - 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 /* Use blocks from reserved pool */
 125 #define EXT4_MB_USE_RESERVED            0x2000
 126
 127 struct ext4_allocation_request {
 128         /* target inode for block we're allocating */
 129         struct inode *inode;
 130         /* how many blocks we want to allocate */
 131         unsigned int len;
 132         /* logical block in target inode */
 133         ext4_lblk_t logical;
 134         /* the closest logical allocated block to the left */
 135         ext4_lblk_t lleft;
 136         /* the closest logical allocated block to the right */
 137         ext4_lblk_t lright;
 138         /* phys. target (a hint) */
 139         ext4_fsblk_t goal;
 140         /* phys. block for the closest logical allocated block to the left */
 141         ext4_fsblk_t pleft;
 142         /* phys. block for the closest logical allocated block to the right */
 143         ext4_fsblk_t pright;
 144         /* flags. see above EXT4_MB_HINT_* */
 145         unsigned int flags;
 146 };
 147
 148 /*
 149  * Logical to physical block mapping, used by ext4_map_blocks()
 150  *
 151  * This structure is used to pass requests into ext4_map_blocks() as
 152  * well as to store the information returned by ext4_map_blocks().  It
 153  * takes less room on the stack than a struct buffer_head.
 154  */
 155 #define EXT4_MAP_NEW            (1 << BH_New)
 156 #define EXT4_MAP_MAPPED         (1 << BH_Mapped)
 157 #define EXT4_MAP_UNWRITTEN      (1 << BH_Unwritten)
 158 #define EXT4_MAP_BOUNDARY       (1 << BH_Boundary)
 159 #define EXT4_MAP_UNINIT         (1 << BH_Uninit)
 160 /* Sometimes (in the bigalloc case, from ext4_da_get_block_prep) the caller of
 161  * ext4_map_blocks wants to know whether or not the underlying cluster has
 162  * already been accounted for. EXT4_MAP_FROM_CLUSTER conveys to the caller that
 163  * the requested mapping was from previously mapped (or delayed allocated)
 164  * cluster. We use BH_AllocFromCluster only for this flag. BH_AllocFromCluster
 165  * should never appear on buffer_head's state flags.
 166  */
 167 #define EXT4_MAP_FROM_CLUSTER   (1 << BH_AllocFromCluster)
 168 #define EXT4_MAP_FLAGS          (EXT4_MAP_NEW | EXT4_MAP_MAPPED |\
 169                                  EXT4_MAP_UNWRITTEN | EXT4_MAP_BOUNDARY |\
 170                                  EXT4_MAP_UNINIT | EXT4_MAP_FROM_CLUSTER)
 171
 172 struct ext4_map_blocks {
 173         ext4_fsblk_t m_pblk;
 174         ext4_lblk_t m_lblk;
 175         unsigned int m_len;
 176         unsigned int m_flags;
 177 };
 178
 179 /*
 180  * Flags for ext4_io_end->flags
 181  */
 182 #define EXT4_IO_END_UNWRITTEN   0x0001
 183 #define EXT4_IO_END_ERROR       0x0002
 184 #define EXT4_IO_END_DIRECT      0x0004
 185
 186 /*
 187  * For converting uninitialized extents on a work queue.
 188  */
 189 typedef struct ext4_io_end {
 190         struct list_head        list;           /* per-file finished IO list */
 191         struct inode            *inode;         /* file being written to */
 192         unsigned int            flag;           /* unwritten or not */
 193         loff_t                  offset;         /* offset in the file */
 194         ssize_t                 size;           /* size of the extent */
 195         struct kiocb            *iocb;          /* iocb struct for AIO */
 196         int                     result;         /* error value for AIO */
 197         atomic_t                count;          /* reference counter */
 198 } ext4_io_end_t;
 199
 200 struct ext4_io_submit {
 201         int                     io_op;
 202         struct bio              *io_bio;
 203         ext4_io_end_t           *io_end;
 204         sector_t                io_next_block;
 205 };
 206
 207 /*
 208  * Special inodes numbers
 209  */
 210 #define EXT4_BAD_INO             1      /* Bad blocks inode */
 211 #define EXT4_ROOT_INO            2      /* Root inode */
 212 #define EXT4_USR_QUOTA_INO       3      /* User quota inode */
 213 #define EXT4_GRP_QUOTA_INO       4      /* Group quota inode */
 214 #define EXT4_BOOT_LOADER_INO     5      /* Boot loader inode */
 215 #define EXT4_UNDEL_DIR_INO       6      /* Undelete directory inode */
 216 #define EXT4_RESIZE_INO          7      /* Reserved group descriptors inode */
 217 #define EXT4_JOURNAL_INO         8      /* Journal inode */
 218
 219 /* First non-reserved inode for old ext4 filesystems */
 220 #define EXT4_GOOD_OLD_FIRST_INO 11
 221
 222 /*
 223  * Maximal count of links to a file
 224  */
 225 #define EXT4_LINK_MAX           65000
 226
 227 /*
 228  * Macro-instructions used to manage several block sizes
 229  */
 230 #define EXT4_MIN_BLOCK_SIZE             1024
 231 #define EXT4_MAX_BLOCK_SIZE             65536
 232 #define EXT4_MIN_BLOCK_LOG_SIZE         10
 233 #define EXT4_MAX_BLOCK_LOG_SIZE         16
 234 #ifdef __KERNEL__
 235 # define EXT4_BLOCK_SIZE(s)             ((s)->s_blocksize)
 236 #else
 237 # define EXT4_BLOCK_SIZE(s)             (EXT4_MIN_BLOCK_SIZE << (s)->s_log_block_size)
 238 #endif
 239 #define EXT4_ADDR_PER_BLOCK(s)          (EXT4_BLOCK_SIZE(s) / sizeof(__u32))
 240 #define EXT4_CLUSTER_SIZE(s)            (EXT4_BLOCK_SIZE(s) << \
 241                                          EXT4_SB(s)->s_cluster_bits)
 242 #ifdef __KERNEL__
 243 # define EXT4_BLOCK_SIZE_BITS(s)        ((s)->s_blocksize_bits)
 244 # define EXT4_CLUSTER_BITS(s)           (EXT4_SB(s)->s_cluster_bits)
 245 #else
 246 # define EXT4_BLOCK_SIZE_BITS(s)        ((s)->s_log_block_size + 10)
 247 #endif
 248 #ifdef __KERNEL__
 249 #define EXT4_ADDR_PER_BLOCK_BITS(s)     (EXT4_SB(s)->s_addr_per_block_bits)
 250 #define EXT4_INODE_SIZE(s)              (EXT4_SB(s)->s_inode_size)
 251 #define EXT4_FIRST_INO(s)               (EXT4_SB(s)->s_first_ino)
 252 #else
 253 #define EXT4_INODE_SIZE(s)      (((s)->s_rev_level == EXT4_GOOD_OLD_REV) ? \
 254                                  EXT4_GOOD_OLD_INODE_SIZE : \
 255                                  (s)->s_inode_size)
 256 #define EXT4_FIRST_INO(s)       (((s)->s_rev_level == EXT4_GOOD_OLD_REV) ? \
 257                                  EXT4_GOOD_OLD_FIRST_INO : \
 258                                  (s)->s_first_ino)
 259 #endif
 260 #define EXT4_BLOCK_ALIGN(size, blkbits)         ALIGN((size), (1 << (blkbits)))
 261
 262 /* Translate a block number to a cluster number */
 263 #define EXT4_B2C(sbi, blk)      ((blk) >> (sbi)->s_cluster_bits)
 264 /* Translate a cluster number to a block number */
 265 #define EXT4_C2B(sbi, cluster)  ((cluster) << (sbi)->s_cluster_bits)
 266 /* Translate # of blks to # of clusters */
 267 #define EXT4_NUM_B2C(sbi, blks) (((blks) + (sbi)->s_cluster_ratio - 1) >> \
 268                                  (sbi)->s_cluster_bits)
 269
 270 /*
 271  * Structure of a blocks group descriptor
 272  */
 273 struct ext4_group_desc
 274 {
 275         __le32  bg_block_bitmap_lo;     /* Blocks bitmap block */
 276         __le32  bg_inode_bitmap_lo;     /* Inodes bitmap block */
 277         __le32  bg_inode_table_lo;      /* Inodes table block */
 278         __le16  bg_free_blocks_count_lo;/* Free blocks count */
 279         __le16  bg_free_inodes_count_lo;/* Free inodes count */
 280         __le16  bg_used_dirs_count_lo;  /* Directories count */
 281         __le16  bg_flags;               /* EXT4_BG_flags (INODE_UNINIT, etc) */
 282         __le32  bg_exclude_bitmap_lo;   /* Exclude bitmap for snapshots */
 283         __le16  bg_block_bitmap_csum_lo;/* crc32c(s_uuid+grp_num+bbitmap) LE */
 284         __le16  bg_inode_bitmap_csum_lo;/* crc32c(s_uuid+grp_num+ibitmap) LE */
 285         __le16  bg_itable_unused_lo;    /* Unused inodes count */
 286         __le16  bg_checksum;            /* crc16(sb_uuid+group+desc) */
 287         __le32  bg_block_bitmap_hi;     /* Blocks bitmap block MSB */
 288         __le32  bg_inode_bitmap_hi;     /* Inodes bitmap block MSB */
 289         __le32  bg_inode_table_hi;      /* Inodes table block MSB */
 290         __le16  bg_free_blocks_count_hi;/* Free blocks count MSB */
 291         __le16  bg_free_inodes_count_hi;/* Free inodes count MSB */
 292         __le16  bg_used_dirs_count_hi;  /* Directories count MSB */
 293         __le16  bg_itable_unused_hi;    /* Unused inodes count MSB */
 294         __le32  bg_exclude_bitmap_hi;   /* Exclude bitmap block MSB */
 295         __le16  bg_block_bitmap_csum_hi;/* crc32c(s_uuid+grp_num+bbitmap) BE */
 296         __le16  bg_inode_bitmap_csum_hi;/* crc32c(s_uuid+grp_num+ibitmap) BE */
 297         __u32   bg_reserved;
 298 };
 299
 300 #define EXT4_BG_INODE_BITMAP_CSUM_HI_END        \
 301         (offsetof(struct ext4_group_desc, bg_inode_bitmap_csum_hi) + \
 302          sizeof(__le16))
 303 #define EXT4_BG_BLOCK_BITMAP_CSUM_HI_END        \
 304         (offsetof(struct ext4_group_desc, bg_block_bitmap_csum_hi) + \
 305          sizeof(__le16))
 306
 307 /*
 308  * Structure of a flex block group info
 309  */
 310
 311 struct flex_groups {
 312         atomic64_t      free_clusters;
 313         atomic_t        free_inodes;
 314         atomic_t        used_dirs;
 315 };
 316
 317 #define EXT4_BG_INODE_UNINIT    0x0001 /* Inode table/bitmap not in use */
 318 #define EXT4_BG_BLOCK_UNINIT    0x0002 /* Block bitmap not in use */
 319 #define EXT4_BG_INODE_ZEROED    0x0004 /* On-disk itable initialized to zero */
 320
 321 /*
 322  * Macro-instructions used to manage group descriptors
 323  */
 324 #define EXT4_MIN_DESC_SIZE              32
 325 #define EXT4_MIN_DESC_SIZE_64BIT        64
 326 #define EXT4_MAX_DESC_SIZE              EXT4_MIN_BLOCK_SIZE
 327 #define EXT4_DESC_SIZE(s)               (EXT4_SB(s)->s_desc_size)
 328 #ifdef __KERNEL__
 329 # define EXT4_BLOCKS_PER_GROUP(s)       (EXT4_SB(s)->s_blocks_per_group)
 330 # define EXT4_CLUSTERS_PER_GROUP(s)     (EXT4_SB(s)->s_clusters_per_group)
 331 # define EXT4_DESC_PER_BLOCK(s)         (EXT4_SB(s)->s_desc_per_block)
 332 # define EXT4_INODES_PER_GROUP(s)       (EXT4_SB(s)->s_inodes_per_group)
 333 # define EXT4_DESC_PER_BLOCK_BITS(s)    (EXT4_SB(s)->s_desc_per_block_bits)
 334 #else
 335 # define EXT4_BLOCKS_PER_GROUP(s)       ((s)->s_blocks_per_group)
 336 # define EXT4_DESC_PER_BLOCK(s)         (EXT4_BLOCK_SIZE(s) / EXT4_DESC_SIZE(s))
 337 # define EXT4_INODES_PER_GROUP(s)       ((s)->s_inodes_per_group)
 338 #endif
 339
 340 /*
 341  * Constants relative to the data blocks
 342  */
 343 #define EXT4_NDIR_BLOCKS                12
 344 #define EXT4_IND_BLOCK                  EXT4_NDIR_BLOCKS
 345 #define EXT4_DIND_BLOCK                 (EXT4_IND_BLOCK + 1)
 346 #define EXT4_TIND_BLOCK                 (EXT4_DIND_BLOCK + 1)
 347 #define EXT4_N_BLOCKS                   (EXT4_TIND_BLOCK + 1)
 348
 349 /*
 350  * Inode flags
 351  */
 352 #define EXT4_SECRM_FL                   0x00000001 /* Secure deletion */
 353 #define EXT4_UNRM_FL                    0x00000002 /* Undelete */
 354 #define EXT4_COMPR_FL                   0x00000004 /* Compress file */
 355 #define EXT4_SYNC_FL                    0x00000008 /* Synchronous updates */
 356 #define EXT4_IMMUTABLE_FL               0x00000010 /* Immutable file */
 357 #define EXT4_APPEND_FL                  0x00000020 /* writes to file may only append */
 358 #define EXT4_NODUMP_FL                  0x00000040 /* do not dump file */
 359 #define EXT4_NOATIME_FL                 0x00000080 /* do not update atime */
 360 /* Reserved for compression usage... */
 361 #define EXT4_DIRTY_FL                   0x00000100
 362 #define EXT4_COMPRBLK_FL                0x00000200 /* One or more compressed clusters */
 363 #define EXT4_NOCOMPR_FL                 0x00000400 /* Don't compress */
 364 #define EXT4_ECOMPR_FL                  0x00000800 /* Compression error */
 365 /* End compression flags --- maybe not all used */
 366 #define EXT4_INDEX_FL                   0x00001000 /* hash-indexed directory */
 367 #define EXT4_IMAGIC_FL                  0x00002000 /* AFS directory */
 368 #define EXT4_JOURNAL_DATA_FL            0x00004000 /* file data should be journaled */
 369 #define EXT4_NOTAIL_FL                  0x00008000 /* file tail should not be merged */
 370 #define EXT4_DIRSYNC_FL                 0x00010000 /* dirsync behaviour (directories only) */
 371 #define EXT4_TOPDIR_FL                  0x00020000 /* Top of directory hierarchies*/
 372 #define EXT4_HUGE_FILE_FL               0x00040000 /* Set to each huge file */
 373 #define EXT4_EXTENTS_FL                 0x00080000 /* Inode uses extents */
 374 #define EXT4_EA_INODE_FL                0x00200000 /* Inode used for large EA */
 375 #define EXT4_EOFBLOCKS_FL               0x00400000 /* Blocks allocated beyond EOF */
 376 #define EXT4_INLINE_DATA_FL             0x10000000 /* Inode has inline data. */
 377 #define EXT4_RESERVED_FL                0x80000000 /* reserved for ext4 lib */
 378
 379 #define EXT4_FL_USER_VISIBLE            0x004BDFFF /* User visible flags */
 380 #define EXT4_FL_USER_MODIFIABLE         0x004380FF /* User modifiable flags */
 381
 382 /* Flags that should be inherited by new inodes from their parent. */
 383 #define EXT4_FL_INHERITED (EXT4_SECRM_FL | EXT4_UNRM_FL | EXT4_COMPR_FL |\
 384                            EXT4_SYNC_FL | EXT4_NODUMP_FL | EXT4_NOATIME_FL |\
 385                            EXT4_NOCOMPR_FL | EXT4_JOURNAL_DATA_FL |\
 386                            EXT4_NOTAIL_FL | EXT4_DIRSYNC_FL)
 387
 388 /* Flags that are appropriate for regular files (all but dir-specific ones). */
 389 #define EXT4_REG_FLMASK (~(EXT4_DIRSYNC_FL | EXT4_TOPDIR_FL))
 390
 391 /* Flags that are appropriate for non-directories/regular files. */
 392 #define EXT4_OTHER_FLMASK (EXT4_NODUMP_FL | EXT4_NOATIME_FL)
 393
 394 /* Mask out flags that are inappropriate for the given type of inode. */
 395 static inline __u32 ext4_mask_flags(umode_t mode, __u32 flags)
 396 {
 397         if (S_ISDIR(mode))
 398                 return flags;
 399         else if (S_ISREG(mode))
 400                 return flags & EXT4_REG_FLMASK;
 401         else
 402                 return flags & EXT4_OTHER_FLMASK;
 403 }
 404
 405 /*
 406  * Inode flags used for atomic set/get
 407  */
 408 enum {
 409         EXT4_INODE_SECRM        = 0,    /* Secure deletion */
 410         EXT4_INODE_UNRM         = 1,    /* Undelete */
 411         EXT4_INODE_COMPR        = 2,    /* Compress file */
 412         EXT4_INODE_SYNC         = 3,    /* Synchronous updates */
 413         EXT4_INODE_IMMUTABLE    = 4,    /* Immutable file */
 414         EXT4_INODE_APPEND       = 5,    /* writes to file may only append */
 415         EXT4_INODE_NODUMP       = 6,    /* do not dump file */
 416         EXT4_INODE_NOATIME      = 7,    /* do not update atime */
 417 /* Reserved for compression usage... */
 418         EXT4_INODE_DIRTY        = 8,
 419         EXT4_INODE_COMPRBLK     = 9,    /* One or more compressed clusters */
 420         EXT4_INODE_NOCOMPR      = 10,   /* Don't compress */
 421         EXT4_INODE_ECOMPR       = 11,   /* Compression error */
 422 /* End compression flags --- maybe not all used */
 423         EXT4_INODE_INDEX        = 12,   /* hash-indexed directory */
 424         EXT4_INODE_IMAGIC       = 13,   /* AFS directory */
 425         EXT4_INODE_JOURNAL_DATA = 14,   /* file data should be journaled */
 426         EXT4_INODE_NOTAIL       = 15,   /* file tail should not be merged */
 427         EXT4_INODE_DIRSYNC      = 16,   /* dirsync behaviour (directories only) */
 428         EXT4_INODE_TOPDIR       = 17,   /* Top of directory hierarchies*/
 429         EXT4_INODE_HUGE_FILE    = 18,   /* Set to each huge file */
 430         EXT4_INODE_EXTENTS      = 19,   /* Inode uses extents */
 431         EXT4_INODE_EA_INODE     = 21,   /* Inode used for large EA */
 432         EXT4_INODE_EOFBLOCKS    = 22,   /* Blocks allocated beyond EOF */
 433         EXT4_INODE_INLINE_DATA  = 28,   /* Data in inode. */
 434         EXT4_INODE_RESERVED     = 31,   /* reserved for ext4 lib */
 435 };
 436
 437 /*
 438  * Since it's pretty easy to mix up bit numbers and hex values, we use a
 439  * build-time check to make sure that EXT4_XXX_FL is consistent with respect to
 440  * EXT4_INODE_XXX. If all is well, the macros will be dropped, so, it won't cost
 441  * any extra space in the compiled kernel image, otherwise, the build will fail.
 442  * It's important that these values are the same, since we are using
 443  * EXT4_INODE_XXX to test for flag values, but EXT4_XXX_FL must be consistent
 444  * with the values of FS_XXX_FL defined in include/linux/fs.h and the on-disk
 445  * values found in ext2, ext3 and ext4 filesystems, and of course the values
 446  * defined in e2fsprogs.
 447  *
 448  * It's not paranoia if the Murphy's Law really *is* out to get you.  :-)
 449  */
 450 #define TEST_FLAG_VALUE(FLAG) (EXT4_##FLAG##_FL == (1 << EXT4_INODE_##FLAG))
 451 #define CHECK_FLAG_VALUE(FLAG) BUILD_BUG_ON(!TEST_FLAG_VALUE(FLAG))
 452
 453 static inline void ext4_check_flag_values(void)
 454 {
 455         CHECK_FLAG_VALUE(SECRM);
 456         CHECK_FLAG_VALUE(UNRM);
 457         CHECK_FLAG_VALUE(COMPR);
 458         CHECK_FLAG_VALUE(SYNC);
 459         CHECK_FLAG_VALUE(IMMUTABLE);
 460         CHECK_FLAG_VALUE(APPEND);
 461         CHECK_FLAG_VALUE(NODUMP);
 462         CHECK_FLAG_VALUE(NOATIME);
 463         CHECK_FLAG_VALUE(DIRTY);
 464         CHECK_FLAG_VALUE(COMPRBLK);
 465         CHECK_FLAG_VALUE(NOCOMPR);
 466         CHECK_FLAG_VALUE(ECOMPR);
 467         CHECK_FLAG_VALUE(INDEX);
 468         CHECK_FLAG_VALUE(IMAGIC);
 469         CHECK_FLAG_VALUE(JOURNAL_DATA);
 470         CHECK_FLAG_VALUE(NOTAIL);
 471         CHECK_FLAG_VALUE(DIRSYNC);
 472         CHECK_FLAG_VALUE(TOPDIR);
 473         CHECK_FLAG_VALUE(HUGE_FILE);
 474         CHECK_FLAG_VALUE(EXTENTS);
 475         CHECK_FLAG_VALUE(EA_INODE);
 476         CHECK_FLAG_VALUE(EOFBLOCKS);
 477         CHECK_FLAG_VALUE(INLINE_DATA);
 478         CHECK_FLAG_VALUE(RESERVED);
 479 }
 480
 481 /* Used to pass group descriptor data when online resize is done */
 482 struct ext4_new_group_input {
 483         __u32 group;            /* Group number for this data */
 484         __u64 block_bitmap;     /* Absolute block number of block bitmap */
 485         __u64 inode_bitmap;     /* Absolute block number of inode bitmap */
 486         __u64 inode_table;      /* Absolute block number of inode table start */
 487         __u32 blocks_count;     /* Total number of blocks in this group */
 488         __u16 reserved_blocks;  /* Number of reserved blocks in this group */
 489         __u16 unused;
 490 };
 491
 492 #if defined(__KERNEL__) && defined(CONFIG_COMPAT)
 493 struct compat_ext4_new_group_input {
 494         u32 group;
 495         compat_u64 block_bitmap;
 496         compat_u64 inode_bitmap;
 497         compat_u64 inode_table;
 498         u32 blocks_count;
 499         u16 reserved_blocks;
 500         u16 unused;
 501 };
 502 #endif
 503
 504 /* The struct ext4_new_group_input in kernel space, with free_blocks_count */
 505 struct ext4_new_group_data {
 506         __u32 group;
 507         __u64 block_bitmap;
 508         __u64 inode_bitmap;
 509         __u64 inode_table;
 510         __u32 blocks_count;
 511         __u16 reserved_blocks;
 512         __u16 unused;
 513         __u32 free_blocks_count;
 514 };
 515
 516 /* Indexes used to index group tables in ext4_new_group_data */
 517 enum {
 518         BLOCK_BITMAP = 0,       /* block bitmap */
 519         INODE_BITMAP,           /* inode bitmap */
 520         INODE_TABLE,            /* inode tables */
 521         GROUP_TABLE_COUNT,
 522 };
 523
 524 /*
 525  * Flags used by ext4_map_blocks()
 526  */
 527         /* Allocate any needed blocks and/or convert an unitialized
 528            extent to be an initialized ext4 */
 529 #define EXT4_GET_BLOCKS_CREATE                  0x0001
 530         /* Request the creation of an unitialized extent */
 531 #define EXT4_GET_BLOCKS_UNINIT_EXT              0x0002
 532 #define EXT4_GET_BLOCKS_CREATE_UNINIT_EXT       (EXT4_GET_BLOCKS_UNINIT_EXT|\
 533                                                  EXT4_GET_BLOCKS_CREATE)
 534         /* Caller is from the delayed allocation writeout path
 535          * finally doing the actual allocation of delayed blocks */
 536 #define EXT4_GET_BLOCKS_DELALLOC_RESERVE        0x0004
 537         /* caller is from the direct IO path, request to creation of an
 538         unitialized extents if not allocated, split the uninitialized
 539         extent if blocks has been preallocated already*/
 540 #define EXT4_GET_BLOCKS_PRE_IO                  0x0008
 541 #define EXT4_GET_BLOCKS_CONVERT                 0x0010
 542 #define EXT4_GET_BLOCKS_IO_CREATE_EXT           (EXT4_GET_BLOCKS_PRE_IO|\
 543                                          EXT4_GET_BLOCKS_CREATE_UNINIT_EXT)
 544         /* Convert extent to initialized after IO complete */
 545 #define EXT4_GET_BLOCKS_IO_CONVERT_EXT          (EXT4_GET_BLOCKS_CONVERT|\
 546                                          EXT4_GET_BLOCKS_CREATE_UNINIT_EXT)
 547         /* Eventual metadata allocation (due to growing extent tree)
 548          * should not fail, so try to use reserved blocks for that.*/
 549 #define EXT4_GET_BLOCKS_METADATA_NOFAIL         0x0020
 550         /* Don't normalize allocation size (used for fallocate) */
 551 #define EXT4_GET_BLOCKS_NO_NORMALIZE            0x0040
 552         /* Request will not result in inode size update (user for fallocate) */
 553 #define EXT4_GET_BLOCKS_KEEP_SIZE               0x0080
 554         /* Do not take i_data_sem locking in ext4_map_blocks */
 555 #define EXT4_GET_BLOCKS_NO_LOCK                 0x0100
 556         /* Do not put hole in extent cache */
 557 #define EXT4_GET_BLOCKS_NO_PUT_HOLE             0x0200
 558
 559 /*
 560  * Flags used by ext4_free_blocks
 561  */
 562 #define EXT4_FREE_BLOCKS_METADATA       0x0001
 563 #define EXT4_FREE_BLOCKS_FORGET         0x0002
 564 #define EXT4_FREE_BLOCKS_VALIDATED      0x0004
 565 #define EXT4_FREE_BLOCKS_NO_QUOT_UPDATE 0x0008
 566 #define EXT4_FREE_BLOCKS_NOFREE_FIRST_CLUSTER   0x0010
 567 #define EXT4_FREE_BLOCKS_NOFREE_LAST_CLUSTER    0x0020
 568
 569 /*
 570  * ioctl commands
 571  */
 572 #define EXT4_IOC_GETFLAGS               FS_IOC_GETFLAGS
 573 #define EXT4_IOC_SETFLAGS               FS_IOC_SETFLAGS
 574 #define EXT4_IOC_GETVERSION             _IOR('f', 3, long)
 575 #define EXT4_IOC_SETVERSION             _IOW('f', 4, long)
 576 #define EXT4_IOC_GETVERSION_OLD         FS_IOC_GETVERSION
 577 #define EXT4_IOC_SETVERSION_OLD         FS_IOC_SETVERSION
 578 #define EXT4_IOC_GETRSVSZ               _IOR('f', 5, long)
 579 #define EXT4_IOC_SETRSVSZ               _IOW('f', 6, long)
 580 #define EXT4_IOC_GROUP_EXTEND           _IOW('f', 7, unsigned long)
 581 #define EXT4_IOC_GROUP_ADD              _IOW('f', 8, struct ext4_new_group_input)
 582 #define EXT4_IOC_MIGRATE                _IO('f', 9)
 583  /* note ioctl 10 reserved for an early version of the FIEMAP ioctl */
 584  /* note ioctl 11 reserved for filesystem-independent FIEMAP ioctl */
 585 #define EXT4_IOC_ALLOC_DA_BLKS          _IO('f', 12)
 586 #define EXT4_IOC_MOVE_EXT               _IOWR('f', 15, struct move_extent)
 587 #define EXT4_IOC_RESIZE_FS              _IOW('f', 16, __u64)
 588 #define EXT4_IOC_SWAP_BOOT              _IO('f', 17)
 589
 590 #if defined(__KERNEL__) && defined(CONFIG_COMPAT)
 591 /*
 592  * ioctl commands in 32 bit emulation
 593  */
 594 #define EXT4_IOC32_GETFLAGS             FS_IOC32_GETFLAGS
 595 #define EXT4_IOC32_SETFLAGS             FS_IOC32_SETFLAGS
 596 #define EXT4_IOC32_GETVERSION           _IOR('f', 3, int)
 597 #define EXT4_IOC32_SETVERSION           _IOW('f', 4, int)
 598 #define EXT4_IOC32_GETRSVSZ             _IOR('f', 5, int)
 599 #define EXT4_IOC32_SETRSVSZ             _IOW('f', 6, int)
 600 #define EXT4_IOC32_GROUP_EXTEND         _IOW('f', 7, unsigned int)
 601 #define EXT4_IOC32_GROUP_ADD            _IOW('f', 8, struct compat_ext4_new_group_input)
 602 #define EXT4_IOC32_GETVERSION_OLD       FS_IOC32_GETVERSION
 603 #define EXT4_IOC32_SETVERSION_OLD       FS_IOC32_SETVERSION
 604 #endif
 605
 606 /* Max physical block we can address w/o extents */
 607 #define EXT4_MAX_BLOCK_FILE_PHYS        0xFFFFFFFF
 608
 609 /*
 610  * Structure of an inode on the disk
 611  */
 612 struct ext4_inode {
 613         __le16  i_mode;         /* File mode */
 614         __le16  i_uid;          /* Low 16 bits of Owner Uid */
 615         __le32  i_size_lo;      /* Size in bytes */
 616         __le32  i_atime;        /* Access time */
 617         __le32  i_ctime;        /* Inode Change time */
 618         __le32  i_mtime;        /* Modification time */
 619         __le32  i_dtime;        /* Deletion Time */
 620         __le16  i_gid;          /* Low 16 bits of Group Id */
 621         __le16  i_links_count;  /* Links count */
 622         __le32  i_blocks_lo;    /* Blocks count */
 623         __le32  i_flags;        /* File flags */
 624         union {
 625                 struct {
 626                         __le32  l_i_version;
 627                 } linux1;
 628                 struct {
 629                         __u32  h_i_translator;
 630                 } hurd1;
 631                 struct {
 632                         __u32  m_i_reserved1;
 633                 } masix1;
 634         } osd1;                         /* OS dependent 1 */
 635         __le32  i_block[EXT4_N_BLOCKS];/* Pointers to blocks */
 636         __le32  i_generation;   /* File version (for NFS) */
 637         __le32  i_file_acl_lo;  /* File ACL */
 638         __le32  i_size_high;
 639         __le32  i_obso_faddr;   /* Obsoleted fragment address */
 640         union {
 641                 struct {
 642                         __le16  l_i_blocks_high; /* were l_i_reserved1 */
 643                         __le16  l_i_file_acl_high;
 644                         __le16  l_i_uid_high;   /* these 2 fields */
 645                         __le16  l_i_gid_high;   /* were reserved2[0] */
 646                         __le16  l_i_checksum_lo;/* crc32c(uuid+inum+inode) LE */
 647                         __le16  l_i_reserved;
 648                 } linux2;
 649                 struct {
 650                         __le16  h_i_reserved1;  /* Obsoleted fragment number/size which are removed in ext4 */
 651                         __u16   h_i_mode_high;
 652                         __u16   h_i_uid_high;
 653                         __u16   h_i_gid_high;
 654                         __u32   h_i_author;
 655                 } hurd2;
 656                 struct {
 657                         __le16  h_i_reserved1;  /* Obsoleted fragment number/size which are removed in ext4 */
 658                         __le16  m_i_file_acl_high;
 659                         __u32   m_i_reserved2[2];
 660                 } masix2;
 661         } osd2;                         /* OS dependent 2 */
 662         __le16  i_extra_isize;
 663         __le16  i_checksum_hi;  /* crc32c(uuid+inum+inode) BE */
 664         __le32  i_ctime_extra;  /* extra Change time      (nsec << 2 | epoch) */
 665         __le32  i_mtime_extra;  /* extra Modification time(nsec << 2 | epoch) */
 666         __le32  i_atime_extra;  /* extra Access time      (nsec << 2 | epoch) */
 667         __le32  i_crtime;       /* File Creation time */
 668         __le32  i_crtime_extra; /* extra FileCreationtime (nsec << 2 | epoch) */
 669         __le32  i_version_hi;   /* high 32 bits for 64-bit version */
 670 };
 671
 672 struct move_extent {
 673         __u32 reserved;         /* should be zero */
 674         __u32 donor_fd;         /* donor file descriptor */
 675         __u64 orig_start;       /* logical start offset in block for orig */
 676         __u64 donor_start;      /* logical start offset in block for donor */
 677         __u64 len;              /* block length to be moved */
 678         __u64 moved_len;        /* moved block length */
 679 };
 680
 681 #define EXT4_EPOCH_BITS 2
 682 #define EXT4_EPOCH_MASK ((1 << EXT4_EPOCH_BITS) - 1)
 683 #define EXT4_NSEC_MASK  (~0UL << EXT4_EPOCH_BITS)
 684
 685 /*
 686  * Extended fields will fit into an inode if the filesystem was formatted
 687  * with large inodes (-I 256 or larger) and there are not currently any EAs
 688  * consuming all of the available space. For new inodes we always reserve
 689  * enough space for the kernel's known extended fields, but for inodes
 690  * created with an old kernel this might not have been the case. None of
 691  * the extended inode fields is critical for correct filesystem operation.
 692  * This macro checks if a certain field fits in the inode. Note that
 693  * inode-size = GOOD_OLD_INODE_SIZE + i_extra_isize
 694  */
 695 #define EXT4_FITS_IN_INODE(ext4_inode, einode, field)   \
 696         ((offsetof(typeof(*ext4_inode), field) +        \
 697           sizeof((ext4_inode)->field))                  \
 698         <= (EXT4_GOOD_OLD_INODE_SIZE +                  \
 699             (einode)->i_extra_isize))                   \
 700
 701 static inline __le32 ext4_encode_extra_time(struct timespec *time)
 702 {
 703        return cpu_to_le32((sizeof(time->tv_sec) > 4 ?
 704                            (time->tv_sec >> 32) & EXT4_EPOCH_MASK : 0) |
 705                           ((time->tv_nsec << EXT4_EPOCH_BITS) & EXT4_NSEC_MASK));
 706 }
 707
 708 static inline void ext4_decode_extra_time(struct timespec *time, __le32 extra)
 709 {
 710        if (sizeof(time->tv_sec) > 4)
 711                time->tv_sec |= (__u64)(le32_to_cpu(extra) & EXT4_EPOCH_MASK)
 712                                << 32;
 713        time->tv_nsec = (le32_to_cpu(extra) & EXT4_NSEC_MASK) >> EXT4_EPOCH_BITS;
 714 }
 715
 716 #define EXT4_INODE_SET_XTIME(xtime, inode, raw_inode)                          \
 717 do {                                                                           \
 718         (raw_inode)->xtime = cpu_to_le32((inode)->xtime.tv_sec);               \
 719         if (EXT4_FITS_IN_INODE(raw_inode, EXT4_I(inode), xtime ## _extra))     \
 720                 (raw_inode)->xtime ## _extra =                                 \
 721                                 ext4_encode_extra_time(&(inode)->xtime);       \
 722 } while (0)
 723
 724 #define EXT4_EINODE_SET_XTIME(xtime, einode, raw_inode)                        \
 725 do {                                                                           \
 726         if (EXT4_FITS_IN_INODE(raw_inode, einode, xtime))                      \
 727                 (raw_inode)->xtime = cpu_to_le32((einode)->xtime.tv_sec);      \
 728         if (EXT4_FITS_IN_INODE(raw_inode, einode, xtime ## _extra))            \
 729                 (raw_inode)->xtime ## _extra =                                 \
 730                                 ext4_encode_extra_time(&(einode)->xtime);      \
 731 } while (0)
 732
 733 #define EXT4_INODE_GET_XTIME(xtime, inode, raw_inode)                          \
 734 do {                                                                           \
 735         (inode)->xtime.tv_sec = (signed)le32_to_cpu((raw_inode)->xtime);       \
 736         if (EXT4_FITS_IN_INODE(raw_inode, EXT4_I(inode), xtime ## _extra))     \
 737                 ext4_decode_extra_time(&(inode)->xtime,                        \
 738                                        raw_inode->xtime ## _extra);            \
 739         else                                                                   \
 740                 (inode)->xtime.tv_nsec = 0;                                    \
 741 } while (0)
 742
 743 #define EXT4_EINODE_GET_XTIME(xtime, einode, raw_inode)                        \
 744 do {                                                                           \
 745         if (EXT4_FITS_IN_INODE(raw_inode, einode, xtime))                      \
 746                 (einode)->xtime.tv_sec =                                       \
 747                         (signed)le32_to_cpu((raw_inode)->xtime);               \
 748         if (EXT4_FITS_IN_INODE(raw_inode, einode, xtime ## _extra))            \
 749                 ext4_decode_extra_time(&(einode)->xtime,                       \
 750                                        raw_inode->xtime ## _extra);            \
 751         else                                                                   \
 752                 (einode)->xtime.tv_nsec = 0;                                   \
 753 } while (0)
 754
 755 #define i_disk_version osd1.linux1.l_i_version
 756
 757 #if defined(__KERNEL__) || defined(__linux__)
 758 #define i_reserved1     osd1.linux1.l_i_reserved1
 759 #define i_file_acl_high osd2.linux2.l_i_file_acl_high
 760 #define i_blocks_high   osd2.linux2.l_i_blocks_high
 761 #define i_uid_low       i_uid
 762 #define i_gid_low       i_gid
 763 #define i_uid_high      osd2.linux2.l_i_uid_high
 764 #define i_gid_high      osd2.linux2.l_i_gid_high
 765 #define i_checksum_lo   osd2.linux2.l_i_checksum_lo
 766
 767 #elif defined(__GNU__)
 768
 769 #define i_translator    osd1.hurd1.h_i_translator
 770 #define i_uid_high      osd2.hurd2.h_i_uid_high
 771 #define i_gid_high      osd2.hurd2.h_i_gid_high
 772 #define i_author        osd2.hurd2.h_i_author
 773
 774 #elif defined(__masix__)
 775
 776 #define i_reserved1     osd1.masix1.m_i_reserved1
 777 #define i_file_acl_high osd2.masix2.m_i_file_acl_high
 778 #define i_reserved2     osd2.masix2.m_i_reserved2
 779
 780 #endif /* defined(__KERNEL__) || defined(__linux__) */
 781
 782 #include "extents_status.h"
 783
 784 /*
 785  * fourth extended file system inode data in memory
 786  */
 787 struct ext4_inode_info {
 788         __le32  i_data[15];     /* unconverted */
 789         __u32   i_dtime;
 790         ext4_fsblk_t    i_file_acl;
 791
 792         /*
 793          * i_block_group is the number of the block group which contains
 794          * this file's inode.  Constant across the lifetime of the inode,
 795          * it is ued for making block allocation decisions - we try to
 796          * place a file's data blocks near its inode block, and new inodes
 797          * near to their parent directory's inode.
 798          */
 799         ext4_group_t    i_block_group;
 800         ext4_lblk_t     i_dir_start_lookup;
 801 #if (BITS_PER_LONG < 64)
 802         unsigned long   i_state_flags;          /* Dynamic state flags */
 803 #endif
 804         unsigned long   i_flags;
 805
 806         /*
 807          * Extended attributes can be read independently of the main file
 808          * data. Taking i_mutex even when reading would cause contention
 809          * between readers of EAs and writers of regular file data, so
 810          * instead we synchronize on xattr_sem when reading or changing
 811          * EAs.
 812          */
 813         struct rw_semaphore xattr_sem;
 814
 815         struct list_head i_orphan;      /* unlinked but open inodes */
 816
 817         /*
 818          * i_disksize keeps track of what the inode size is ON DISK, not
 819          * in memory.  During truncate, i_size is set to the new size by
 820          * the VFS prior to calling ext4_truncate(), but the filesystem won't
 821          * set i_disksize to 0 until the truncate is actually under way.
 822          *
 823          * The intent is that i_disksize always represents the blocks which
 824          * are used by this file.  This allows recovery to restart truncate
 825          * on orphans if we crash during truncate.  We actually write i_disksize
 826          * into the on-disk inode when writing inodes out, instead of i_size.
 827          *
 828          * The only time when i_disksize and i_size may be different is when
 829          * a truncate is in progress.  The only things which change i_disksize
 830          * are ext4_get_block (growth) and ext4_truncate (shrinkth).
 831          */
 832         loff_t  i_disksize;
 833
 834         /*
 835          * i_data_sem is for serialising ext4_truncate() against
 836          * ext4_getblock().  In the 2.4 ext2 design, great chunks of inode's
 837          * data tree are chopped off during truncate. We can't do that in
 838          * ext4 because whenever we perform intermediate commits during
 839          * truncate, the inode and all the metadata blocks *must* be in a
 840          * consistent state which allows truncation of the orphans to restart
 841          * during recovery.  Hence we must fix the get_block-vs-truncate race
 842          * by other means, so we have i_data_sem.
 843          */
 844         struct rw_semaphore i_data_sem;
 845         struct inode vfs_inode;
 846         struct jbd2_inode *jinode;
 847
 848         /*
 849          * File creation time. Its function is same as that of
 850          * struct timespec i_{a,c,m}time in the generic inode.
 851          */
 852         struct timespec i_crtime;
 853
 854         /* mballoc */
 855         struct list_head i_prealloc_list;
 856         spinlock_t i_prealloc_lock;
 857
 858         /* extents status tree */
 859         struct ext4_es_tree i_es_tree;
 860         rwlock_t i_es_lock;
 861         struct list_head i_es_lru;
 862         unsigned int i_es_lru_nr;       /* protected by i_es_lock */
 863
 864         /* ialloc */
 865         ext4_group_t    i_last_alloc_group;
 866
 867         /* allocation reservation info for delalloc */
 868         /* In case of bigalloc, these refer to clusters rather than blocks */
 869         unsigned int i_reserved_data_blocks;
 870         unsigned int i_reserved_meta_blocks;
 871         unsigned int i_allocated_meta_blocks;
 872         ext4_lblk_t i_da_metadata_calc_last_lblock;
 873         int i_da_metadata_calc_len;
 874
 875         /* on-disk additional length */
 876         __u16 i_extra_isize;
 877
 878         /* Indicate the inline data space. */
 879         u16 i_inline_off;
 880         u16 i_inline_size;
 881
 882 #ifdef CONFIG_QUOTA
 883         /* quota space reservation, managed internally by quota code */
 884         qsize_t i_reserved_quota;
 885 #endif
 886
 887         /* completed IOs that might need unwritten extents handling */
 888         struct list_head i_completed_io_list;
 889         spinlock_t i_completed_io_lock;
 890         atomic_t i_ioend_count; /* Number of outstanding io_end structs */
 891         atomic_t i_unwritten; /* Nr. of inflight conversions pending */
 892         struct work_struct i_unwritten_work;    /* deferred extent conversion */
 893
 894         spinlock_t i_block_reservation_lock;
 895
 896         /*
 897          * Transactions that contain inode's metadata needed to complete
 898          * fsync and fdatasync, respectively.
 899          */
 900         tid_t i_sync_tid;
 901         tid_t i_datasync_tid;
 902
 903         /* Precomputed uuid+inum+igen checksum for seeding inode checksums */
 904         __u32 i_csum_seed;
 905 };
 906
 907 /*
 908  * File system states
 909  */
 910 #define EXT4_VALID_FS                   0x0001  /* Unmounted cleanly */
 911 #define EXT4_ERROR_FS                   0x0002  /* Errors detected */
 912 #define EXT4_ORPHAN_FS                  0x0004  /* Orphans being recovered */
 913
 914 /*
 915  * Misc. filesystem flags
 916  */
 917 #define EXT2_FLAGS_SIGNED_HASH          0x0001  /* Signed dirhash in use */
 918 #define EXT2_FLAGS_UNSIGNED_HASH        0x0002  /* Unsigned dirhash in use */
 919 #define EXT2_FLAGS_TEST_FILESYS         0x0004  /* to test development code */
 920
 921 /*
 922  * Mount flags set via mount options or defaults
 923  */
 924 #define EXT4_MOUNT_GRPID                0x00004 /* Create files with directory's group */
 925 #define EXT4_MOUNT_DEBUG                0x00008 /* Some debugging messages */
 926 #define EXT4_MOUNT_ERRORS_CONT          0x00010 /* Continue on errors */
 927 #define EXT4_MOUNT_ERRORS_RO            0x00020 /* Remount fs ro on errors */
 928 #define EXT4_MOUNT_ERRORS_PANIC         0x00040 /* Panic on errors */
 929 #define EXT4_MOUNT_ERRORS_MASK          0x00070
 930 #define EXT4_MOUNT_MINIX_DF             0x00080 /* Mimics the Minix statfs */
 931 #define EXT4_MOUNT_NOLOAD               0x00100 /* Don't use existing journal*/
 932 #define EXT4_MOUNT_DATA_FLAGS           0x00C00 /* Mode for data writes: */
 933 #define EXT4_MOUNT_JOURNAL_DATA         0x00400 /* Write data to journal */
 934 #define EXT4_MOUNT_ORDERED_DATA         0x00800 /* Flush data before commit */
 935 #define EXT4_MOUNT_WRITEBACK_DATA       0x00C00 /* No data ordering */
 936 #define EXT4_MOUNT_UPDATE_JOURNAL       0x01000 /* Update the journal format */
 937 #define EXT4_MOUNT_NO_UID32             0x02000  /* Disable 32-bit UIDs */
 938 #define EXT4_MOUNT_XATTR_USER           0x04000 /* Extended user attributes */
 939 #define EXT4_MOUNT_POSIX_ACL            0x08000 /* POSIX Access Control Lists */
 940 #define EXT4_MOUNT_NO_AUTO_DA_ALLOC     0x10000 /* No auto delalloc mapping */
 941 #define EXT4_MOUNT_BARRIER              0x20000 /* Use block barriers */
 942 #define EXT4_MOUNT_QUOTA                0x80000 /* Some quota option set */
 943 #define EXT4_MOUNT_USRQUOTA             0x100000 /* "old" user quota */
 944 #define EXT4_MOUNT_GRPQUOTA             0x200000 /* "old" group quota */
 945 #define EXT4_MOUNT_DIOREAD_NOLOCK       0x400000 /* Enable support for dio read nolocking */
 946 #define EXT4_MOUNT_JOURNAL_CHECKSUM     0x800000 /* Journal checksums */
 947 #define EXT4_MOUNT_JOURNAL_ASYNC_COMMIT 0x1000000 /* Journal Async Commit */
 948 #define EXT4_MOUNT_DELALLOC             0x8000000 /* Delalloc support */
 949 #define EXT4_MOUNT_DATA_ERR_ABORT       0x10000000 /* Abort on file data write */
 950 #define EXT4_MOUNT_BLOCK_VALIDITY       0x20000000 /* Block validity checking */
 951 #define EXT4_MOUNT_DISCARD              0x40000000 /* Issue DISCARD requests */
 952 #define EXT4_MOUNT_INIT_INODE_TABLE     0x80000000 /* Initialize uninitialized itables */
 953
 954 /*
 955  * Mount flags set either automatically (could not be set by mount option)
 956  * based on per file system feature or property or in special cases such as
 957  * distinguishing between explicit mount option definition and default.
 958  */
 959 #define EXT4_MOUNT2_EXPLICIT_DELALLOC   0x00000001 /* User explicitly
 960                                                       specified delalloc */
 961 #define EXT4_MOUNT2_STD_GROUP_SIZE      0x00000002 /* We have standard group
 962                                                       size of blocksize * 8
 963                                                       blocks */
 964
 965 #define clear_opt(sb, opt)              EXT4_SB(sb)->s_mount_opt &= \
 966                                                 ~EXT4_MOUNT_##opt
 967 #define set_opt(sb, opt)                EXT4_SB(sb)->s_mount_opt |= \
 968                                                 EXT4_MOUNT_##opt
 969 #define test_opt(sb, opt)               (EXT4_SB(sb)->s_mount_opt & \
 970                                          EXT4_MOUNT_##opt)
 971
 972 #define clear_opt2(sb, opt)             EXT4_SB(sb)->s_mount_opt2 &= \
 973                                                 ~EXT4_MOUNT2_##opt
 974 #define set_opt2(sb, opt)               EXT4_SB(sb)->s_mount_opt2 |= \
 975                                                 EXT4_MOUNT2_##opt
 976 #define test_opt2(sb, opt)              (EXT4_SB(sb)->s_mount_opt2 & \
 977                                          EXT4_MOUNT2_##opt)
 978
 979 #define ext4_test_and_set_bit           __test_and_set_bit_le
 980 #define ext4_set_bit                    __set_bit_le
 981 #define ext4_set_bit_atomic             ext2_set_bit_atomic
 982 #define ext4_test_and_clear_bit         __test_and_clear_bit_le
 983 #define ext4_clear_bit                  __clear_bit_le
 984 #define ext4_clear_bit_atomic           ext2_clear_bit_atomic
 985 #define ext4_test_bit                   test_bit_le
 986 #define ext4_find_next_zero_bit         find_next_zero_bit_le
 987 #define ext4_find_next_bit              find_next_bit_le
 988
 989 extern void ext4_set_bits(void *bm, int cur, int len);
 990
 991 /*
 992  * Maximal mount counts between two filesystem checks
 993  */
 994 #define EXT4_DFL_MAX_MNT_COUNT          20      /* Allow 20 mounts */
 995 #define EXT4_DFL_CHECKINTERVAL          0       /* Don't use interval check */
 996
 997 /*
 998  * Behaviour when detecting errors
 999  */
1000 #define EXT4_ERRORS_CONTINUE            1       /* Continue execution */
1001 #define EXT4_ERRORS_RO                  2       /* Remount fs read-only */
1002 #define EXT4_ERRORS_PANIC               3       /* Panic */
1003 #define EXT4_ERRORS_DEFAULT             EXT4_ERRORS_CONTINUE
1004
1005 /* Metadata checksum algorithm codes */
1006 #define EXT4_CRC32C_CHKSUM              1
1007
1008 /*
1009  * Structure of the super block
1010  */
1011 struct ext4_super_block {
1012 /*00*/  __le32  s_inodes_count;         /* Inodes count */
1013         __le32  s_blocks_count_lo;      /* Blocks count */
1014         __le32  s_r_blocks_count_lo;    /* Reserved blocks count */
1015         __le32  s_free_blocks_count_lo; /* Free blocks count */
1016 /*10*/  __le32  s_free_inodes_count;    /* Free inodes count */
1017         __le32  s_first_data_block;     /* First Data Block */
1018         __le32  s_log_block_size;       /* Block size */
1019         __le32  s_log_cluster_size;     /* Allocation cluster size */
1020 /*20*/  __le32  s_blocks_per_group;     /* # Blocks per group */
1021         __le32  s_clusters_per_group;   /* # Clusters per group */
1022         __le32  s_inodes_per_group;     /* # Inodes per group */
1023         __le32  s_mtime;                /* Mount time */
1024 /*30*/  __le32  s_wtime;                /* Write time */
1025         __le16  s_mnt_count;            /* Mount count */
1026         __le16  s_max_mnt_count;        /* Maximal mount count */
1027         __le16  s_magic;                /* Magic signature */
1028         __le16  s_state;                /* File system state */
1029         __le16  s_errors;               /* Behaviour when detecting errors */
1030         __le16  s_minor_rev_level;      /* minor revision level */
1031 /*40*/  __le32  s_lastcheck;            /* time of last check */
1032         __le32  s_checkinterval;        /* max. time between checks */
1033         __le32  s_creator_os;           /* OS */
1034         __le32  s_rev_level;            /* Revision level */
1035 /*50*/  __le16  s_def_resuid;           /* Default uid for reserved blocks */
1036         __le16  s_def_resgid;           /* Default gid for reserved blocks */
1037         /*
1038          * These fields are for EXT4_DYNAMIC_REV superblocks only.
1039          *
1040          * Note: the difference between the compatible feature set and
1041          * the incompatible feature set is that if there is a bit set
1042          * in the incompatible feature set that the kernel doesn't
1043          * know about, it should refuse to mount the filesystem.
1044          *
1045          * e2fsck's requirements are more strict; if it doesn't know
1046          * about a feature in either the compatible or incompatible
1047          * feature set, it must abort and not try to meddle with
1048          * things it doesn't understand...
1049          */
1050         __le32  s_first_ino;            /* First non-reserved inode */
1051         __le16  s_inode_size;           /* size of inode structure */
1052         __le16  s_block_group_nr;       /* block group # of this superblock */
1053         __le32  s_feature_compat;       /* compatible feature set */
1054 /*60*/  __le32  s_feature_incompat;     /* incompatible feature set */
1055         __le32  s_feature_ro_compat;    /* readonly-compatible feature set */
1056 /*68*/  __u8    s_uuid[16];             /* 128-bit uuid for volume */
1057 /*78*/  char    s_volume_name[16];      /* volume name */
1058 /*88*/  char    s_last_mounted[64];     /* directory where last mounted */
1059 /*C8*/  __le32  s_algorithm_usage_bitmap; /* For compression */
1060         /*
1061          * Performance hints.  Directory preallocation should only
1062          * happen if the EXT4_FEATURE_COMPAT_DIR_PREALLOC flag is on.
1063          */
1064         __u8    s_prealloc_blocks;      /* Nr of blocks to try to preallocate*/
1065         __u8    s_prealloc_dir_blocks;  /* Nr to preallocate for dirs */
1066         __le16  s_reserved_gdt_blocks;  /* Per group desc for online growth */
1067         /*
1068          * Journaling support valid if EXT4_FEATURE_COMPAT_HAS_JOURNAL set.
1069          */
1070 /*D0*/  __u8    s_journal_uuid[16];     /* uuid of journal superblock */
1071 /*E0*/  __le32  s_journal_inum;         /* inode number of journal file */
1072         __le32  s_journal_dev;          /* device number of journal file */
1073         __le32  s_last_orphan;          /* start of list of inodes to delete */
1074         __le32  s_hash_seed[4];         /* HTREE hash seed */
1075         __u8    s_def_hash_version;     /* Default hash version to use */
1076         __u8    s_jnl_backup_type;
1077         __le16  s_desc_size;            /* size of group descriptor */
1078 /*100*/ __le32  s_default_mount_opts;
1079         __le32  s_first_meta_bg;        /* First metablock block group */
1080         __le32  s_mkfs_time;            /* When the filesystem was created */
1081         __le32  s_jnl_blocks[17];       /* Backup of the journal inode */
1082         /* 64bit support valid if EXT4_FEATURE_COMPAT_64BIT */
1083 /*150*/ __le32  s_blocks_count_hi;      /* Blocks count */
1084         __le32  s_r_blocks_count_hi;    /* Reserved blocks count */
1085         __le32  s_free_blocks_count_hi; /* Free blocks count */
1086         __le16  s_min_extra_isize;      /* All inodes have at least # bytes */
1087         __le16  s_want_extra_isize;     /* New inodes should reserve # bytes */
1088         __le32  s_flags;                /* Miscellaneous flags */
1089         __le16  s_raid_stride;          /* RAID stride */
1090         __le16  s_mmp_update_interval;  /* # seconds to wait in MMP checking */
1091         __le64  s_mmp_block;            /* Block for multi-mount protection */
1092         __le32  s_raid_stripe_width;    /* blocks on all data disks (N*stride)*/
1093         __u8    s_log_groups_per_flex;  /* FLEX_BG group size */
1094         __u8    s_checksum_type;        /* metadata checksum algorithm used */
1095         __le16  s_reserved_pad;
1096         __le64  s_kbytes_written;       /* nr of lifetime kilobytes written */
1097         __le32  s_snapshot_inum;        /* Inode number of active snapshot */
1098         __le32  s_snapshot_id;          /* sequential ID of active snapshot */
1099         __le64  s_snapshot_r_blocks_count; /* reserved blocks for active
1100                                               snapshot's future use */
1101         __le32  s_snapshot_list;        /* inode number of the head of the
1102                                            on-disk snapshot list */
1103 #define EXT4_S_ERR_START offsetof(struct ext4_super_block, s_error_count)
1104         __le32  s_error_count;          /* number of fs errors */
1105         __le32  s_first_error_time;     /* first time an error happened */
1106         __le32  s_first_error_ino;      /* inode involved in first error */
1107         __le64  s_first_error_block;    /* block involved of first error */
1108         __u8    s_first_error_func[32]; /* function where the error happened */
1109         __le32  s_first_error_line;     /* line number where error happened */
1110         __le32  s_last_error_time;      /* most recent time of an error */
1111         __le32  s_last_error_ino;       /* inode involved in last error */
1112         __le32  s_last_error_line;      /* line number where error happened */
1113         __le64  s_last_error_block;     /* block involved of last error */
1114         __u8    s_last_error_func[32];  /* function where the error happened */
1115 #define EXT4_S_ERR_END offsetof(struct ext4_super_block, s_mount_opts)
1116         __u8    s_mount_opts[64];
1117         __le32  s_usr_quota_inum;       /* inode for tracking user quota */
1118         __le32  s_grp_quota_inum;       /* inode for tracking group quota */
1119         __le32  s_overhead_clusters;    /* overhead blocks/clusters in fs */
1120         __le32  s_reserved[108];        /* Padding to the end of the block */
1121         __le32  s_checksum;             /* crc32c(superblock) */
1122 };
1123
1124 #define EXT4_S_ERR_LEN (EXT4_S_ERR_END - EXT4_S_ERR_START)
1125
1126 #ifdef __KERNEL__
1127
1128 /*
1129  * run-time mount flags
1130  */
1131 #define EXT4_MF_MNTDIR_SAMPLED  0x0001
1132 #define EXT4_MF_FS_ABORTED      0x0002  /* Fatal error detected */
1133
1134 /*
1135  * fourth extended-fs super-block data in memory
1136  */
1137 struct ext4_sb_info {
1138         unsigned long s_desc_size;      /* Size of a group descriptor in bytes */
1139         unsigned long s_inodes_per_block;/* Number of inodes per block */
1140         unsigned long s_blocks_per_group;/* Number of blocks in a group */
1141         unsigned long s_clusters_per_group; /* Number of clusters in a group */
1142         unsigned long s_inodes_per_group;/* Number of inodes in a group */
1143         unsigned long s_itb_per_group;  /* Number of inode table blocks per group */
1144         unsigned long s_gdb_count;      /* Number of group descriptor blocks */
1145         unsigned long s_desc_per_block; /* Number of group descriptors per block */
1146         ext4_group_t s_groups_count;    /* Number of groups in the fs */
1147         ext4_group_t s_blockfile_groups;/* Groups acceptable for non-extent files */
1148         unsigned long s_overhead;  /* # of fs overhead clusters */
1149         unsigned int s_cluster_ratio;   /* Number of blocks per cluster */
1150         unsigned int s_cluster_bits;    /* log2 of s_cluster_ratio */
1151         loff_t s_bitmap_maxbytes;       /* max bytes for bitmap files */
1152         struct buffer_head * s_sbh;     /* Buffer containing the super block */
1153         struct ext4_super_block *s_es;  /* Pointer to the super block in the buffer */
1154         struct buffer_head **s_group_desc;
1155         unsigned int s_mount_opt;
1156         unsigned int s_mount_opt2;
1157         unsigned int s_mount_flags;
1158         unsigned int s_def_mount_opt;
1159         ext4_fsblk_t s_sb_block;
1160         atomic64_t s_resv_clusters;
1161         kuid_t s_resuid;
1162         kgid_t s_resgid;
1163         unsigned short s_mount_state;
1164         unsigned short s_pad;
1165         int s_addr_per_block_bits;
1166         int s_desc_per_block_bits;
1167         int s_inode_size;
1168         int s_first_ino;
1169         unsigned int s_inode_readahead_blks;
1170         unsigned int s_inode_goal;
1171         spinlock_t s_next_gen_lock;
1172         u32 s_next_generation;
1173         u32 s_hash_seed[4];
1174         int s_def_hash_version;
1175         int s_hash_unsigned;    /* 3 if hash should be signed, 0 if not */
1176         struct percpu_counter s_freeclusters_counter;
1177         struct percpu_counter s_freeinodes_counter;
1178         struct percpu_counter s_dirs_counter;
1179         struct percpu_counter s_dirtyclusters_counter;
1180         struct blockgroup_lock *s_blockgroup_lock;
1181         struct proc_dir_entry *s_proc;
1182         struct kobject s_kobj;
1183         struct completion s_kobj_unregister;
1184         struct super_block *s_sb;
1185
1186         /* Journaling */
1187         struct journal_s *s_journal;
1188         struct list_head s_orphan;
1189         struct mutex s_orphan_lock;
1190         unsigned long s_resize_flags;           /* Flags indicating if there
1191                                                    is a resizer */
1192         unsigned long s_commit_interval;
1193         u32 s_max_batch_time;
1194         u32 s_min_batch_time;
1195         struct block_device *journal_bdev;
1196 #ifdef CONFIG_QUOTA
1197         char *s_qf_names[MAXQUOTAS];            /* Names of quota files with journalled quota */
1198         int s_jquota_fmt;                       /* Format of quota to use */
1199 #endif
1200         unsigned int s_want_extra_isize; /* New inodes should reserve # bytes */
1201         struct rb_root system_blks;
1202
1203 #ifdef EXTENTS_STATS
1204         /* ext4 extents stats */
1205         unsigned long s_ext_min;
1206         unsigned long s_ext_max;
1207         unsigned long s_depth_max;
1208         spinlock_t s_ext_stats_lock;
1209         unsigned long s_ext_blocks;
1210         unsigned long s_ext_extents;
1211 #endif
1212
1213         /* for buddy allocator */
1214         struct ext4_group_info ***s_group_info;
1215         struct inode *s_buddy_cache;
1216         spinlock_t s_md_lock;
1217         unsigned short *s_mb_offsets;
1218         unsigned int *s_mb_maxs;
1219         unsigned int s_group_info_size;
1220
1221         /* tunables */
1222         unsigned long s_stripe;
1223         unsigned int s_mb_stream_request;
1224         unsigned int s_mb_max_to_scan;
1225         unsigned int s_mb_min_to_scan;
1226         unsigned int s_mb_stats;
1227         unsigned int s_mb_order2_reqs;
1228         unsigned int s_mb_group_prealloc;
1229         unsigned int s_max_dir_size_kb;
1230         /* where last allocation was done - for stream allocation */
1231         unsigned long s_mb_last_group;
1232         unsigned long s_mb_last_start;
1233
1234         /* stats for buddy allocator */
1235         atomic_t s_bal_reqs;    /* number of reqs with len > 1 */
1236         atomic_t s_bal_success; /* we found long enough chunks */
1237         atomic_t s_bal_allocated;       /* in blocks */
1238         atomic_t s_bal_ex_scanned;      /* total extents scanned */
1239         atomic_t s_bal_goals;   /* goal hits */
1240         atomic_t s_bal_breaks;  /* too long searches */
1241         atomic_t s_bal_2orders; /* 2^order hits */
1242         spinlock_t s_bal_lock;
1243         unsigned long s_mb_buddies_generated;
1244         unsigned long long s_mb_generation_time;
1245         atomic_t s_mb_lost_chunks;
1246         atomic_t s_mb_preallocated;
1247         atomic_t s_mb_discarded;
1248         atomic_t s_lock_busy;
1249
1250         /* locality groups */
1251         struct ext4_locality_group __percpu *s_locality_groups;
1252
1253         /* for write statistics */
1254         unsigned long s_sectors_written_start;
1255         u64 s_kbytes_written;
1256
1257         /* the size of zero-out chunk */
1258         unsigned int s_extent_max_zeroout_kb;
1259
1260         unsigned int s_log_groups_per_flex;
1261         struct flex_groups *s_flex_groups;
1262         ext4_group_t s_flex_groups_allocated;
1263
1264         /* workqueue for dio unwritten */
1265         struct workqueue_struct *dio_unwritten_wq;
1266
1267         /* timer for periodic error stats printing */
1268         struct timer_list s_err_report;
1269
1270         /* Lazy inode table initialization info */
1271         struct ext4_li_request *s_li_request;
1272         /* Wait multiplier for lazy initialization thread */
1273         unsigned int s_li_wait_mult;
1274
1275         /* Kernel thread for multiple mount protection */
1276         struct task_struct *s_mmp_tsk;
1277
1278         /* record the last minlen when FITRIM is called. */
1279         atomic_t s_last_trim_minblks;
1280
1281         /* Reference to checksum algorithm driver via cryptoapi */
1282         struct crypto_shash *s_chksum_driver;
1283
1284         /* Precomputed FS UUID checksum for seeding other checksums */
1285         __u32 s_csum_seed;
1286
1287         /* Reclaim extents from extent status tree */
1288         struct shrinker s_es_shrinker;
1289         struct list_head s_es_lru;
1290         struct percpu_counter s_extent_cache_cnt;
1291         spinlock_t s_es_lru_lock ____cacheline_aligned_in_smp;
1292 };
1293
1294 static inline struct ext4_sb_info *EXT4_SB(struct super_block *sb)
1295 {
1296         return sb->s_fs_info;
1297 }
1298 static inline struct ext4_inode_info *EXT4_I(struct inode *inode)
1299 {
1300         return container_of(inode, struct ext4_inode_info, vfs_inode);
1301 }
1302
1303 static inline struct timespec ext4_current_time(struct inode *inode)
1304 {
1305         return (inode->i_sb->s_time_gran < NSEC_PER_SEC) ?
1306                 current_fs_time(inode->i_sb) : CURRENT_TIME_SEC;
1307 }
1308
1309 static inline int ext4_valid_inum(struct super_block *sb, unsigned long ino)
1310 {
1311         return ino == EXT4_ROOT_INO ||
1312                 ino == EXT4_USR_QUOTA_INO ||
1313                 ino == EXT4_GRP_QUOTA_INO ||
1314                 ino == EXT4_BOOT_LOADER_INO ||
1315                 ino == EXT4_JOURNAL_INO ||
1316                 ino == EXT4_RESIZE_INO ||
1317                 (ino >= EXT4_FIRST_INO(sb) &&
1318                  ino <= le32_to_cpu(EXT4_SB(sb)->s_es->s_inodes_count));
1319 }
1320
1321 static inline void ext4_set_io_unwritten_flag(struct inode *inode,
1322                                               struct ext4_io_end *io_end)
1323 {
1324         if (!(io_end->flag & EXT4_IO_END_UNWRITTEN)) {
1325                 io_end->flag |= EXT4_IO_END_UNWRITTEN;
1326                 atomic_inc(&EXT4_I(inode)->i_unwritten);
1327         }
1328 }
1329
1330 static inline ext4_io_end_t *ext4_inode_aio(struct inode *inode)
1331 {
1332         return inode->i_private;
1333 }
1334
1335 static inline void ext4_inode_aio_set(struct inode *inode, ext4_io_end_t *io)
1336 {
1337         inode->i_private = io;
1338 }
1339
1340 /*
1341  * Inode dynamic state flags
1342  */
1343 enum {
1344         EXT4_STATE_JDATA,               /* journaled data exists */
1345         EXT4_STATE_NEW,                 /* inode is newly created */
1346         EXT4_STATE_XATTR,               /* has in-inode xattrs */
1347         EXT4_STATE_NO_EXPAND,           /* No space for expansion */
1348         EXT4_STATE_DA_ALLOC_CLOSE,      /* Alloc DA blks on close */
1349         EXT4_STATE_EXT_MIGRATE,         /* Inode is migrating */
1350         EXT4_STATE_DIO_UNWRITTEN,       /* need convert on dio done*/
1351         EXT4_STATE_NEWENTRY,            /* File just added to dir */
1352         EXT4_STATE_DELALLOC_RESERVED,   /* blks already reserved for delalloc */
1353         EXT4_STATE_DIOREAD_LOCK,        /* Disable support for dio read
1354                                            nolocking */
1355         EXT4_STATE_MAY_INLINE_DATA,     /* may have in-inode data */
1356         EXT4_STATE_ORDERED_MODE,        /* data=ordered mode */
1357 };
1358
1359 #define EXT4_INODE_BIT_FNS(name, field, offset)                         \
1360 static inline int ext4_test_inode_##name(struct inode *inode, int bit)  \
1361 {                                                                       \
1362         return test_bit(bit + (offset), &EXT4_I(inode)->i_##field);     \
1363 }                                                                       \
1364 static inline void ext4_set_inode_##name(struct inode *inode, int bit)  \
1365 {                                                                       \
1366         set_bit(bit + (offset), &EXT4_I(inode)->i_##field);             \
1367 }                                                                       \
1368 static inline void ext4_clear_inode_##name(struct inode *inode, int bit) \
1369 {                                                                       \
1370         clear_bit(bit + (offset), &EXT4_I(inode)->i_##field);           \
1371 }
1372
1373 EXT4_INODE_BIT_FNS(flag, flags, 0)
1374 #if (BITS_PER_LONG < 64)
1375 EXT4_INODE_BIT_FNS(state, state_flags, 0)
1376
1377 static inline void ext4_clear_state_flags(struct ext4_inode_info *ei)
1378 {
1379         (ei)->i_state_flags = 0;
1380 }
1381 #else
1382 EXT4_INODE_BIT_FNS(state, flags, 32)
1383
1384 static inline void ext4_clear_state_flags(struct ext4_inode_info *ei)
1385 {
1386         /* We depend on the fact that callers will set i_flags */
1387 }
1388 #endif
1389 #else
1390 /* Assume that user mode programs are passing in an ext4fs superblock, not
1391  * a kernel struct super_block.  This will allow us to call the feature-test
1392  * macros from user land. */
1393 #define EXT4_SB(sb)     (sb)
1394 #endif
1395
1396 #define NEXT_ORPHAN(inode) EXT4_I(inode)->i_dtime
1397
1398 /*
1399  * Codes for operating systems
1400  */
1401 #define EXT4_OS_LINUX           0
1402 #define EXT4_OS_HURD            1
1403 #define EXT4_OS_MASIX           2
1404 #define EXT4_OS_FREEBSD         3
1405 #define EXT4_OS_LITES           4
1406
1407 /*
1408  * Revision levels
1409  */
1410 #define EXT4_GOOD_OLD_REV       0       /* The good old (original) format */
1411 #define EXT4_DYNAMIC_REV        1       /* V2 format w/ dynamic inode sizes */
1412
1413 #define EXT4_CURRENT_REV        EXT4_GOOD_OLD_REV
1414 #define EXT4_MAX_SUPP_REV       EXT4_DYNAMIC_REV
1415
1416 #define EXT4_GOOD_OLD_INODE_SIZE 128
1417
1418 /*
1419  * Feature set definitions
1420  */
1421
1422 #define EXT4_HAS_COMPAT_FEATURE(sb,mask)                        \
1423         ((EXT4_SB(sb)->s_es->s_feature_compat & cpu_to_le32(mask)) != 0)
1424 #define EXT4_HAS_RO_COMPAT_FEATURE(sb,mask)                     \
1425         ((EXT4_SB(sb)->s_es->s_feature_ro_compat & cpu_to_le32(mask)) != 0)
1426 #define EXT4_HAS_INCOMPAT_FEATURE(sb,mask)                      \
1427         ((EXT4_SB(sb)->s_es->s_feature_incompat & cpu_to_le32(mask)) != 0)
1428 #define EXT4_SET_COMPAT_FEATURE(sb,mask)                        \
1429         EXT4_SB(sb)->s_es->s_feature_compat |= cpu_to_le32(mask)
1430 #define EXT4_SET_RO_COMPAT_FEATURE(sb,mask)                     \
1431         EXT4_SB(sb)->s_es->s_feature_ro_compat |= cpu_to_le32(mask)
1432 #define EXT4_SET_INCOMPAT_FEATURE(sb,mask)                      \
1433         EXT4_SB(sb)->s_es->s_feature_incompat |= cpu_to_le32(mask)
1434 #define EXT4_CLEAR_COMPAT_FEATURE(sb,mask)                      \
1435         EXT4_SB(sb)->s_es->s_feature_compat &= ~cpu_to_le32(mask)
1436 #define EXT4_CLEAR_RO_COMPAT_FEATURE(sb,mask)                   \
1437         EXT4_SB(sb)->s_es->s_feature_ro_compat &= ~cpu_to_le32(mask)
1438 #define EXT4_CLEAR_INCOMPAT_FEATURE(sb,mask)                    \
1439         EXT4_SB(sb)->s_es->s_feature_incompat &= ~cpu_to_le32(mask)
1440
1441 #define EXT4_FEATURE_COMPAT_DIR_PREALLOC        0x0001
1442 #define EXT4_FEATURE_COMPAT_IMAGIC_INODES       0x0002
1443 #define EXT4_FEATURE_COMPAT_HAS_JOURNAL         0x0004
1444 #define EXT4_FEATURE_COMPAT_EXT_ATTR            0x0008
1445 #define EXT4_FEATURE_COMPAT_RESIZE_INODE        0x0010
1446 #define EXT4_FEATURE_COMPAT_DIR_INDEX           0x0020
1447
1448 #define EXT4_FEATURE_RO_COMPAT_SPARSE_SUPER     0x0001
1449 #define EXT4_FEATURE_RO_COMPAT_LARGE_FILE       0x0002
1450 #define EXT4_FEATURE_RO_COMPAT_BTREE_DIR        0x0004
1451 #define EXT4_FEATURE_RO_COMPAT_HUGE_FILE        0x0008
1452 #define EXT4_FEATURE_RO_COMPAT_GDT_CSUM         0x0010
1453 #define EXT4_FEATURE_RO_COMPAT_DIR_NLINK        0x0020
1454 #define EXT4_FEATURE_RO_COMPAT_EXTRA_ISIZE      0x0040
1455 #define EXT4_FEATURE_RO_COMPAT_QUOTA            0x0100
1456 #define EXT4_FEATURE_RO_COMPAT_BIGALLOC         0x0200
1457 /*
1458  * METADATA_CSUM also enables group descriptor checksums (GDT_CSUM).  When
1459  * METADATA_CSUM is set, group descriptor checksums use the same algorithm as
1460  * all other data structures' checksums.  However, the METADATA_CSUM and
1461  * GDT_CSUM bits are mutually exclusive.
1462  */
1463 #define EXT4_FEATURE_RO_COMPAT_METADATA_CSUM    0x0400
1464
1465 #define EXT4_FEATURE_INCOMPAT_COMPRESSION       0x0001
1466 #define EXT4_FEATURE_INCOMPAT_FILETYPE          0x0002
1467 #define EXT4_FEATURE_INCOMPAT_RECOVER           0x0004 /* Needs recovery */
1468 #define EXT4_FEATURE_INCOMPAT_JOURNAL_DEV       0x0008 /* Journal device */
1469 #define EXT4_FEATURE_INCOMPAT_META_BG           0x0010
1470 #define EXT4_FEATURE_INCOMPAT_EXTENTS           0x0040 /* extents support */
1471 #define EXT4_FEATURE_INCOMPAT_64BIT             0x0080
1472 #define EXT4_FEATURE_INCOMPAT_MMP               0x0100
1473 #define EXT4_FEATURE_INCOMPAT_FLEX_BG           0x0200
1474 #define EXT4_FEATURE_INCOMPAT_EA_INODE          0x0400 /* EA in inode */
1475 #define EXT4_FEATURE_INCOMPAT_DIRDATA           0x1000 /* data in dirent */
1476 #define EXT4_FEATURE_INCOMPAT_BG_USE_META_CSUM  0x2000 /* use crc32c for bg */
1477 #define EXT4_FEATURE_INCOMPAT_LARGEDIR          0x4000 /* >2GB or 3-lvl htree */
1478 #define EXT4_FEATURE_INCOMPAT_INLINE_DATA       0x8000 /* data in inode */
1479
1480 #define EXT2_FEATURE_COMPAT_SUPP        EXT4_FEATURE_COMPAT_EXT_ATTR
1481 #define EXT2_FEATURE_INCOMPAT_SUPP      (EXT4_FEATURE_INCOMPAT_FILETYPE| \
1482                                          EXT4_FEATURE_INCOMPAT_META_BG)
1483 #define EXT2_FEATURE_RO_COMPAT_SUPP     (EXT4_FEATURE_RO_COMPAT_SPARSE_SUPER| \
1484                                          EXT4_FEATURE_RO_COMPAT_LARGE_FILE| \
1485                                          EXT4_FEATURE_RO_COMPAT_BTREE_DIR)
1486
1487 #define EXT3_FEATURE_COMPAT_SUPP        EXT4_FEATURE_COMPAT_EXT_ATTR
1488 #define EXT3_FEATURE_INCOMPAT_SUPP      (EXT4_FEATURE_INCOMPAT_FILETYPE| \
1489                                          EXT4_FEATURE_INCOMPAT_RECOVER| \
1490                                          EXT4_FEATURE_INCOMPAT_META_BG)
1491 #define EXT3_FEATURE_RO_COMPAT_SUPP     (EXT4_FEATURE_RO_COMPAT_SPARSE_SUPER| \
1492                                          EXT4_FEATURE_RO_COMPAT_LARGE_FILE| \
1493                                          EXT4_FEATURE_RO_COMPAT_BTREE_DIR)
1494
1495 #define EXT4_FEATURE_COMPAT_SUPP        EXT2_FEATURE_COMPAT_EXT_ATTR
1496 #define EXT4_FEATURE_INCOMPAT_SUPP      (EXT4_FEATURE_INCOMPAT_FILETYPE| \
1497                                          EXT4_FEATURE_INCOMPAT_RECOVER| \
1498                                          EXT4_FEATURE_INCOMPAT_META_BG| \
1499                                          EXT4_FEATURE_INCOMPAT_EXTENTS| \
1500                                          EXT4_FEATURE_INCOMPAT_64BIT| \
1501                                          EXT4_FEATURE_INCOMPAT_FLEX_BG| \
1502                                          EXT4_FEATURE_INCOMPAT_MMP |    \
1503                                          EXT4_FEATURE_INCOMPAT_INLINE_DATA)
1504 #define EXT4_FEATURE_RO_COMPAT_SUPP     (EXT4_FEATURE_RO_COMPAT_SPARSE_SUPER| \
1505                                          EXT4_FEATURE_RO_COMPAT_LARGE_FILE| \
1506                                          EXT4_FEATURE_RO_COMPAT_GDT_CSUM| \
1507                                          EXT4_FEATURE_RO_COMPAT_DIR_NLINK | \
1508                                          EXT4_FEATURE_RO_COMPAT_EXTRA_ISIZE | \
1509                                          EXT4_FEATURE_RO_COMPAT_BTREE_DIR |\
1510                                          EXT4_FEATURE_RO_COMPAT_HUGE_FILE |\
1511                                          EXT4_FEATURE_RO_COMPAT_BIGALLOC |\
1512                                          EXT4_FEATURE_RO_COMPAT_METADATA_CSUM|\
1513                                          EXT4_FEATURE_RO_COMPAT_QUOTA)
1514
1515 /*
1516  * Default values for user and/or group using reserved blocks
1517  */
1518 #define EXT4_DEF_RESUID         0
1519 #define EXT4_DEF_RESGID         0
1520
1521 #define EXT4_DEF_INODE_READAHEAD_BLKS   32
1522
1523 /*
1524  * Default mount options
1525  */
1526 #define EXT4_DEFM_DEBUG         0x0001
1527 #define EXT4_DEFM_BSDGROUPS     0x0002
1528 #define EXT4_DEFM_XATTR_USER    0x0004
1529 #define EXT4_DEFM_ACL           0x0008
1530 #define EXT4_DEFM_UID16         0x0010
1531 #define EXT4_DEFM_JMODE         0x0060
1532 #define EXT4_DEFM_JMODE_DATA    0x0020
1533 #define EXT4_DEFM_JMODE_ORDERED 0x0040
1534 #define EXT4_DEFM_JMODE_WBACK   0x0060
1535 #define EXT4_DEFM_NOBARRIER     0x0100
1536 #define EXT4_DEFM_BLOCK_VALIDITY 0x0200
1537 #define EXT4_DEFM_DISCARD       0x0400
1538 #define EXT4_DEFM_NODELALLOC    0x0800
1539
1540 /*
1541  * Default journal batch times
1542  */
1543 #define EXT4_DEF_MIN_BATCH_TIME 0
1544 #define EXT4_DEF_MAX_BATCH_TIME 15000 /* 15ms */
1545
1546 /*
1547  * Minimum number of groups in a flexgroup before we separate out
1548  * directories into the first block group of a flexgroup
1549  */
1550 #define EXT4_FLEX_SIZE_DIR_ALLOC_SCHEME 4
1551
1552 /*
1553  * Structure of a directory entry
1554  */
1555 #define EXT4_NAME_LEN 255
1556
1557 struct ext4_dir_entry {
1558         __le32  inode;                  /* Inode number */
1559         __le16  rec_len;                /* Directory entry length */
1560         __le16  name_len;               /* Name length */
1561         char    name[EXT4_NAME_LEN];    /* File name */
1562 };
1563
1564 /*
1565  * The new version of the directory entry.  Since EXT4 structures are
1566  * stored in intel byte order, and the name_len field could never be
1567  * bigger than 255 chars, it's safe to reclaim the extra byte for the
1568  * file_type field.
1569  */
1570 struct ext4_dir_entry_2 {
1571         __le32  inode;                  /* Inode number */
1572         __le16  rec_len;                /* Directory entry length */
1573         __u8    name_len;               /* Name length */
1574         __u8    file_type;
1575         char    name[EXT4_NAME_LEN];    /* File name */
1576 };
1577
1578 /*
1579  * This is a bogus directory entry at the end of each leaf block that
1580  * records checksums.
1581  */
1582 struct ext4_dir_entry_tail {
1583         __le32  det_reserved_zero1;     /* Pretend to be unused */
1584         __le16  det_rec_len;            /* 12 */
1585         __u8    det_reserved_zero2;     /* Zero name length */
1586         __u8    det_reserved_ft;        /* 0xDE, fake file type */
1587         __le32  det_checksum;           /* crc32c(uuid+inum+dirblock) */
1588 };
1589
1590 #define EXT4_DIRENT_TAIL(block, blocksize) \
1591         ((struct ext4_dir_entry_tail *)(((void *)(block)) + \
1592                                         ((blocksize) - \
1593                                          sizeof(struct ext4_dir_entry_tail))))
1594
1595 /*
1596  * Ext4 directory file types.  Only the low 3 bits are used.  The
1597  * other bits are reserved for now.
1598  */
1599 #define EXT4_FT_UNKNOWN         0
1600 #define EXT4_FT_REG_FILE        1
1601 #define EXT4_FT_DIR             2
1602 #define EXT4_FT_CHRDEV          3
1603 #define EXT4_FT_BLKDEV          4
1604 #define EXT4_FT_FIFO            5
1605 #define EXT4_FT_SOCK            6
1606 #define EXT4_FT_SYMLINK         7
1607
1608 #define EXT4_FT_MAX             8
1609
1610 #define EXT4_FT_DIR_CSUM        0xDE
1611
1612 /*
1613  * EXT4_DIR_PAD defines the directory entries boundaries
1614  *
1615  * NOTE: It must be a multiple of 4
1616  */
1617 #define EXT4_DIR_PAD                    4
1618 #define EXT4_DIR_ROUND                  (EXT4_DIR_PAD - 1)
1619 #define EXT4_DIR_REC_LEN(name_len)      (((name_len) + 8 + EXT4_DIR_ROUND) & \
1620                                          ~EXT4_DIR_ROUND)
1621 #define EXT4_MAX_REC_LEN                ((1<<16)-1)
1622
1623 /*
1624  * If we ever get support for fs block sizes > page_size, we'll need
1625  * to remove the #if statements in the next two functions...
1626  */
1627 static inline unsigned int
1628 ext4_rec_len_from_disk(__le16 dlen, unsigned blocksize)
1629 {
1630         unsigned len = le16_to_cpu(dlen);
1631
1632 #if (PAGE_CACHE_SIZE >= 65536)
1633         if (len == EXT4_MAX_REC_LEN || len == 0)
1634                 return blocksize;
1635         return (len & 65532) | ((len & 3) << 16);
1636 #else
1637         return len;
1638 #endif
1639 }
1640
1641 static inline __le16 ext4_rec_len_to_disk(unsigned len, unsigned blocksize)
1642 {
1643         if ((len > blocksize) || (blocksize > (1 << 18)) || (len & 3))
1644                 BUG();
1645 #if (PAGE_CACHE_SIZE >= 65536)
1646         if (len < 65536)
1647                 return cpu_to_le16(len);
1648         if (len == blocksize) {
1649                 if (blocksize == 65536)
1650                         return cpu_to_le16(EXT4_MAX_REC_LEN);
1651                 else
1652                         return cpu_to_le16(0);
1653         }
1654         return cpu_to_le16((len & 65532) | ((len >> 16) & 3));
1655 #else
1656         return cpu_to_le16(len);
1657 #endif
1658 }
1659
1660 /*
1661  * Hash Tree Directory indexing
1662  * (c) Daniel Phillips, 2001
1663  */
1664
1665 #define is_dx(dir) (EXT4_HAS_COMPAT_FEATURE(dir->i_sb, \
1666                                       EXT4_FEATURE_COMPAT_DIR_INDEX) && \
1667                     ext4_test_inode_flag((dir), EXT4_INODE_INDEX))
1668 #define EXT4_DIR_LINK_MAX(dir) (!is_dx(dir) && (dir)->i_nlink >= EXT4_LINK_MAX)
1669 #define EXT4_DIR_LINK_EMPTY(dir) ((dir)->i_nlink == 2 || (dir)->i_nlink == 1)
1670
1671 /* Legal values for the dx_root hash_version field: */
1672
1673 #define DX_HASH_LEGACY          0
1674 #define DX_HASH_HALF_MD4        1
1675 #define DX_HASH_TEA             2
1676 #define DX_HASH_LEGACY_UNSIGNED 3
1677 #define DX_HASH_HALF_MD4_UNSIGNED       4
1678 #define DX_HASH_TEA_UNSIGNED            5
1679
1680 static inline u32 ext4_chksum(struct ext4_sb_info *sbi, u32 crc,
1681                               const void *address, unsigned int length)
1682 {
1683         struct {
1684                 struct shash_desc shash;
1685                 char ctx[4];
1686         } desc;
1687         int err;
1688
1689         BUG_ON(crypto_shash_descsize(sbi->s_chksum_driver)!=sizeof(desc.ctx));
1690
1691         desc.shash.tfm = sbi->s_chksum_driver;
1692         desc.shash.flags = 0;
1693         *(u32 *)desc.ctx = crc;
1694
1695         err = crypto_shash_update(&desc.shash, address, length);
1696         BUG_ON(err);
1697
1698         return *(u32 *)desc.ctx;
1699 }
1700
1701 #ifdef __KERNEL__
1702
1703 /* hash info structure used by the directory hash */
1704 struct dx_hash_info
1705 {
1706         u32             hash;
1707         u32             minor_hash;
1708         int             hash_version;
1709         u32             *seed;
1710 };
1711
1712
1713 /* 32 and 64 bit signed EOF for dx directories */
1714 #define EXT4_HTREE_EOF_32BIT   ((1UL  << (32 - 1)) - 1)
1715 #define EXT4_HTREE_EOF_64BIT   ((1ULL << (64 - 1)) - 1)
1716
1717
1718 /*
1719  * Control parameters used by ext4_htree_next_block
1720  */
1721 #define HASH_NB_ALWAYS          1
1722
1723
1724 /*
1725  * Describe an inode's exact location on disk and in memory
1726  */
1727 struct ext4_iloc
1728 {
1729         struct buffer_head *bh;
1730         unsigned long offset;
1731         ext4_group_t block_group;
1732 };
1733
1734 static inline struct ext4_inode *ext4_raw_inode(struct ext4_iloc *iloc)
1735 {
1736         return (struct ext4_inode *) (iloc->bh->b_data + iloc->offset);
1737 }
1738
1739 /*
1740  * This structure is stuffed into the struct file's private_data field
1741  * for directories.  It is where we put information so that we can do
1742  * readdir operations in hash tree order.
1743  */
1744 struct dir_private_info {
1745         struct rb_root  root;
1746         struct rb_node  *curr_node;
1747         struct fname    *extra_fname;
1748         loff_t          last_pos;
1749         __u32           curr_hash;
1750         __u32           curr_minor_hash;
1751         __u32           next_hash;
1752 };
1753
1754 /* calculate the first block number of the group */
1755 static inline ext4_fsblk_t
1756 ext4_group_first_block_no(struct super_block *sb, ext4_group_t group_no)
1757 {
1758         return group_no * (ext4_fsblk_t)EXT4_BLOCKS_PER_GROUP(sb) +
1759                 le32_to_cpu(EXT4_SB(sb)->s_es->s_first_data_block);
1760 }
1761
1762 /*
1763  * Special error return code only used by dx_probe() and its callers.
1764  */
1765 #define ERR_BAD_DX_DIR  -75000
1766
1767 /*
1768  * Timeout and state flag for lazy initialization inode thread.
1769  */
1770 #define EXT4_DEF_LI_WAIT_MULT                   10
1771 #define EXT4_DEF_LI_MAX_START_DELAY             5
1772 #define EXT4_LAZYINIT_QUIT                      0x0001
1773 #define EXT4_LAZYINIT_RUNNING                   0x0002
1774
1775 /*
1776  * Lazy inode table initialization info
1777  */
1778 struct ext4_lazy_init {
1779         unsigned long           li_state;
1780         struct list_head        li_request_list;
1781         struct mutex            li_list_mtx;
1782 };
1783
1784 struct ext4_li_request {
1785         struct super_block      *lr_super;
1786         struct ext4_sb_info     *lr_sbi;
1787         ext4_group_t            lr_next_group;
1788         struct list_head        lr_request;
1789         unsigned long           lr_next_sched;
1790         unsigned long           lr_timeout;
1791 };
1792
1793 struct ext4_features {
1794         struct kobject f_kobj;
1795         struct completion f_kobj_unregister;
1796 };
1797
1798 /*
1799  * This structure will be used for multiple mount protection. It will be
1800  * written into the block number saved in the s_mmp_block field in the
1801  * superblock. Programs that check MMP should assume that if
1802  * SEQ_FSCK (or any unknown code above SEQ_MAX) is present then it is NOT safe
1803  * to use the filesystem, regardless of how old the timestamp is.
1804  */
1805 #define EXT4_MMP_MAGIC     0x004D4D50U /* ASCII for MMP */
1806 #define EXT4_MMP_SEQ_CLEAN 0xFF4D4D50U /* mmp_seq value for clean unmount */
1807 #define EXT4_MMP_SEQ_FSCK  0xE24D4D50U /* mmp_seq value when being fscked */
1808 #define EXT4_MMP_SEQ_MAX   0xE24D4D4FU /* maximum valid mmp_seq value */
1809
1810 struct mmp_struct {
1811         __le32  mmp_magic;              /* Magic number for MMP */
1812         __le32  mmp_seq;                /* Sequence no. updated periodically */
1813
1814         /*
1815          * mmp_time, mmp_nodename & mmp_bdevname are only used for information
1816          * purposes and do not affect the correctness of the algorithm
1817          */
1818         __le64  mmp_time;               /* Time last updated */
1819         char    mmp_nodename[64];       /* Node which last updated MMP block */
1820         char    mmp_bdevname[32];       /* Bdev which last updated MMP block */
1821
1822         /*
1823          * mmp_check_interval is used to verify if the MMP block has been
1824          * updated on the block device. The value is updated based on the
1825          * maximum time to write the MMP block during an update cycle.
1826          */
1827         __le16  mmp_check_interval;
1828
1829         __le16  mmp_pad1;
1830         __le32  mmp_pad2[226];
1831         __le32  mmp_checksum;           /* crc32c(uuid+mmp_block) */
1832 };
1833
1834 /* arguments passed to the mmp thread */
1835 struct mmpd_data {
1836         struct buffer_head *bh; /* bh from initial read_mmp_block() */
1837         struct super_block *sb;  /* super block of the fs */
1838 };
1839
1840 /*
1841  * Check interval multiplier
1842  * The MMP block is written every update interval and initially checked every
1843  * update interval x the multiplier (the value is then adapted based on the
1844  * write latency). The reason is that writes can be delayed under load and we
1845  * don't want readers to incorrectly assume that the filesystem is no longer
1846  * in use.
1847  */
1848 #define EXT4_MMP_CHECK_MULT             2UL
1849
1850 /*
1851  * Minimum interval for MMP checking in seconds.
1852  */
1853 #define EXT4_MMP_MIN_CHECK_INTERVAL     5UL
1854
1855 /*
1856  * Maximum interval for MMP checking in seconds.
1857  */
1858 #define EXT4_MMP_MAX_CHECK_INTERVAL     300UL
1859
1860 /*
1861  * Function prototypes
1862  */
1863
1864 /*
1865  * Ok, these declarations are also in <linux/kernel.h> but none of the
1866  * ext4 source programs needs to include it so they are duplicated here.
1867  */
1868 # define NORET_TYPE     /**/
1869 # define ATTRIB_NORET   __attribute__((noreturn))
1870 # define NORET_AND      noreturn,
1871
1872 /* bitmap.c */
1873 extern unsigned int ext4_count_free(char *bitmap, unsigned numchars);
1874 void ext4_inode_bitmap_csum_set(struct super_block *sb, ext4_group_t group,
1875                                 struct ext4_group_desc *gdp,
1876                                 struct buffer_head *bh, int sz);
1877 int ext4_inode_bitmap_csum_verify(struct super_block *sb, ext4_group_t group,
1878                                   struct ext4_group_desc *gdp,
1879                                   struct buffer_head *bh, int sz);
1880 void ext4_block_bitmap_csum_set(struct super_block *sb, ext4_group_t group,
1881                                 struct ext4_group_desc *gdp,
1882                                 struct buffer_head *bh);
1883 int ext4_block_bitmap_csum_verify(struct super_block *sb, ext4_group_t group,
1884                                   struct ext4_group_desc *gdp,
1885                                   struct buffer_head *bh);
1886
1887 /* balloc.c */
1888 extern void ext4_get_group_no_and_offset(struct super_block *sb,
1889                                          ext4_fsblk_t blocknr,
1890                                          ext4_group_t *blockgrpp,
1891                                          ext4_grpblk_t *offsetp);
1892 extern ext4_group_t ext4_get_group_number(struct super_block *sb,
1893                                           ext4_fsblk_t block);
1894
1895 extern void ext4_validate_block_bitmap(struct super_block *sb,
1896                                        struct ext4_group_desc *desc,
1897                                        unsigned int block_group,
1898                                        struct buffer_head *bh);
1899 extern unsigned int ext4_block_group(struct super_block *sb,
1900                         ext4_fsblk_t blocknr);
1901 extern ext4_grpblk_t ext4_block_group_offset(struct super_block *sb,
1902                         ext4_fsblk_t blocknr);
1903 extern int ext4_bg_has_super(struct super_block *sb, ext4_group_t group);
1904 extern unsigned long ext4_bg_num_gdb(struct super_block *sb,
1905                         ext4_group_t group);
1906 extern ext4_fsblk_t ext4_new_meta_blocks(handle_t *handle, struct inode *inode,
1907                                          ext4_fsblk_t goal,
1908                                          unsigned int flags,
1909                                          unsigned long *count,
1910                                          int *errp);
1911 extern int ext4_claim_free_clusters(struct ext4_sb_info *sbi,
1912                                     s64 nclusters, unsigned int flags);
1913 extern ext4_fsblk_t ext4_count_free_clusters(struct super_block *);
1914 extern void ext4_check_blocks_bitmap(struct super_block *);
1915 extern struct ext4_group_desc * ext4_get_group_desc(struct super_block * sb,
1916                                                     ext4_group_t block_group,
1917                                                     struct buffer_head ** bh);
1918 extern int ext4_should_retry_alloc(struct super_block *sb, int *retries);
1919
1920 extern struct buffer_head *ext4_read_block_bitmap_nowait(struct super_block *sb,
1921                                                 ext4_group_t block_group);
1922 extern int ext4_wait_block_bitmap(struct super_block *sb,
1923                                   ext4_group_t block_group,
1924                                   struct buffer_head *bh);
1925 extern struct buffer_head *ext4_read_block_bitmap(struct super_block *sb,
1926                                                   ext4_group_t block_group);
1927 extern void ext4_init_block_bitmap(struct super_block *sb,
1928                                    struct buffer_head *bh,
1929                                    ext4_group_t group,
1930                                    struct ext4_group_desc *desc);
1931 extern unsigned ext4_free_clusters_after_init(struct super_block *sb,
1932                                               ext4_group_t block_group,
1933                                               struct ext4_group_desc *gdp);
1934 extern unsigned ext4_num_overhead_clusters(struct super_block *sb,
1935                                            ext4_group_t block_group,
1936                                            struct ext4_group_desc *gdp);
1937 ext4_fsblk_t ext4_inode_to_goal_block(struct inode *);
1938
1939 /* dir.c */
1940 extern int __ext4_check_dir_entry(const char *, unsigned int, struct inode *,
1941                                   struct file *,
1942                                   struct ext4_dir_entry_2 *,
1943                                   struct buffer_head *, char *, int,
1944                                   unsigned int);
1945 #define ext4_check_dir_entry(dir, filp, de, bh, buf, size, offset)      \
1946         unlikely(__ext4_check_dir_entry(__func__, __LINE__, (dir), (filp), \
1947                                         (de), (bh), (buf), (size), (offset)))
1948 extern int ext4_htree_store_dirent(struct file *dir_file, __u32 hash,
1949                                     __u32 minor_hash,
1950                                     struct ext4_dir_entry_2 *dirent);
1951 extern void ext4_htree_free_dir_info(struct dir_private_info *p);
1952 extern int ext4_find_dest_de(struct inode *dir, struct inode *inode,
1953                              struct buffer_head *bh,
1954                              void *buf, int buf_size,
1955                              const char *name, int namelen,
1956                              struct ext4_dir_entry_2 **dest_de);
1957 void ext4_insert_dentry(struct inode *inode,
1958                         struct ext4_dir_entry_2 *de,
1959                         int buf_size,
1960                         const char *name, int namelen);
1961 static inline void ext4_update_dx_flag(struct inode *inode)
1962 {
1963         if (!EXT4_HAS_COMPAT_FEATURE(inode->i_sb,
1964                                      EXT4_FEATURE_COMPAT_DIR_INDEX))
1965                 ext4_clear_inode_flag(inode, EXT4_INODE_INDEX);
1966 }
1967 static unsigned char ext4_filetype_table[] = {
1968         DT_UNKNOWN, DT_REG, DT_DIR, DT_CHR, DT_BLK, DT_FIFO, DT_SOCK, DT_LNK
1969 };
1970
1971 static inline  unsigned char get_dtype(struct super_block *sb, int filetype)
1972 {
1973         if (!EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_FILETYPE) ||
1974             (filetype >= EXT4_FT_MAX))
1975                 return DT_UNKNOWN;
1976
1977         return ext4_filetype_table[filetype];
1978 }
1979
1980 /* fsync.c */
1981 extern int ext4_sync_file(struct file *, loff_t, loff_t, int);
1982 extern int ext4_flush_unwritten_io(struct inode *);
1983
1984 /* hash.c */
1985 extern int ext4fs_dirhash(const char *name, int len, struct
1986                           dx_hash_info *hinfo);
1987
1988 /* ialloc.c */
1989 extern struct inode *__ext4_new_inode(handle_t *, struct inode *, umode_t,
1990                                       const struct qstr *qstr, __u32 goal,
1991                                       uid_t *owner, int handle_type,
1992                                       unsigned int line_no, int nblocks);
1993
1994 #define ext4_new_inode(handle, dir, mode, qstr, goal, owner) \
1995         __ext4_new_inode((handle), (dir), (mode), (qstr), (goal), (owner), \
1996                          0, 0, 0)
1997 #define ext4_new_inode_start_handle(dir, mode, qstr, goal, owner, \
1998                                     type, nblocks)                  \
1999         __ext4_new_inode(NULL, (dir), (mode), (qstr), (goal), (owner), \
2000                          (type), __LINE__, (nblocks))
2001
2002
2003 extern void ext4_free_inode(handle_t *, struct inode *);
2004 extern struct inode * ext4_orphan_get(struct super_block *, unsigned long);
2005 extern unsigned long ext4_count_free_inodes(struct super_block *);
2006 extern unsigned long ext4_count_dirs(struct super_block *);
2007 extern void ext4_check_inodes_bitmap(struct super_block *);
2008 extern void ext4_mark_bitmap_end(int start_bit, int end_bit, char *bitmap);
2009 extern int ext4_init_inode_table(struct super_block *sb,
2010                                  ext4_group_t group, int barrier);
2011 extern void ext4_end_bitmap_read(struct buffer_head *bh, int uptodate);
2012
2013 /* mballoc.c */
2014 extern long ext4_mb_stats;
2015 extern long ext4_mb_max_to_scan;
2016 extern int ext4_mb_init(struct super_block *);
2017 extern int ext4_mb_release(struct super_block *);
2018 extern ext4_fsblk_t ext4_mb_new_blocks(handle_t *,
2019                                 struct ext4_allocation_request *, int *);
2020 extern int ext4_mb_reserve_blocks(struct super_block *, int);
2021 extern void ext4_discard_preallocations(struct inode *);
2022 extern int __init ext4_init_mballoc(void);
2023 extern void ext4_exit_mballoc(void);
2024 extern void ext4_free_blocks(handle_t *handle, struct inode *inode,
2025                              struct buffer_head *bh, ext4_fsblk_t block,
2026                              unsigned long count, int flags);
2027 extern int ext4_mb_alloc_groupinfo(struct super_block *sb,
2028                                    ext4_group_t ngroups);
2029 extern int ext4_mb_add_groupinfo(struct super_block *sb,
2030                 ext4_group_t i, struct ext4_group_desc *desc);
2031 extern int ext4_group_add_blocks(handle_t *handle, struct super_block *sb,
2032                                 ext4_fsblk_t block, unsigned long count);
2033 extern int ext4_trim_fs(struct super_block *, struct fstrim_range *);
2034
2035 /* inode.c */
2036 struct buffer_head *ext4_getblk(handle_t *, struct inode *,
2037                                                 ext4_lblk_t, int, int *);
2038 struct buffer_head *ext4_bread(handle_t *, struct inode *,
2039                                                 ext4_lblk_t, int, int *);
2040 int ext4_get_block_write(struct inode *inode, sector_t iblock,
2041                          struct buffer_head *bh_result, int create);
2042 int ext4_get_block(struct inode *inode, sector_t iblock,
2043                                 struct buffer_head *bh_result, int create);
2044 int ext4_da_get_block_prep(struct inode *inode, sector_t iblock,
2045                            struct buffer_head *bh, int create);
2046 int ext4_walk_page_buffers(handle_t *handle,
2047                            struct buffer_head *head,
2048                            unsigned from,
2049                            unsigned to,
2050                            int *partial,
2051                            int (*fn)(handle_t *handle,
2052                                      struct buffer_head *bh));
2053 int do_journal_get_write_access(handle_t *handle,
2054                                 struct buffer_head *bh);
2055 #define FALL_BACK_TO_NONDELALLOC 1
2056 #define CONVERT_INLINE_DATA      2
2057
2058 extern struct inode *ext4_iget(struct super_block *, unsigned long);
2059 extern int  ext4_write_inode(struct inode *, struct writeback_control *);
2060 extern int  ext4_setattr(struct dentry *, struct iattr *);
2061 extern int  ext4_getattr(struct vfsmount *mnt, struct dentry *dentry,
2062                                 struct kstat *stat);
2063 extern void ext4_evict_inode(struct inode *);
2064 extern void ext4_clear_inode(struct inode *);
2065 extern int  ext4_sync_inode(handle_t *, struct inode *);
2066 extern void ext4_dirty_inode(struct inode *, int);
2067 extern int ext4_change_inode_journal_flag(struct inode *, int);
2068 extern int ext4_get_inode_loc(struct inode *, struct ext4_iloc *);
2069 extern int ext4_can_truncate(struct inode *inode);
2070 extern void ext4_truncate(struct inode *);
2071 extern int ext4_punch_hole(struct file *file, loff_t offset, loff_t length);
2072 extern int ext4_truncate_restart_trans(handle_t *, struct inode *, int nblocks);
2073 extern void ext4_set_inode_flags(struct inode *);
2074 extern void ext4_get_inode_flags(struct ext4_inode_info *);
2075 extern int ext4_alloc_da_blocks(struct inode *inode);
2076 extern void ext4_set_aops(struct inode *inode);
2077 extern int ext4_writepage_trans_blocks(struct inode *);
2078 extern int ext4_chunk_trans_blocks(struct inode *, int nrblocks);
2079 extern int ext4_block_truncate_page(handle_t *handle,
2080                 struct address_space *mapping, loff_t from);
2081 extern int ext4_block_zero_page_range(handle_t *handle,
2082                 struct address_space *mapping, loff_t from, loff_t length);
2083 extern int ext4_zero_partial_blocks(handle_t *handle, struct inode *inode,
2084                              loff_t lstart, loff_t lend);
2085 extern int ext4_page_mkwrite(struct vm_area_struct *vma, struct vm_fault *vmf);
2086 extern qsize_t *ext4_get_reserved_space(struct inode *inode);
2087 extern void ext4_da_update_reserve_space(struct inode *inode,
2088                                         int used, int quota_claim);
2089
2090 /* indirect.c */
2091 extern int ext4_ind_map_blocks(handle_t *handle, struct inode *inode,
2092                                 struct ext4_map_blocks *map, int flags);
2093 extern ssize_t ext4_ind_direct_IO(int rw, struct kiocb *iocb,
2094                                 const struct iovec *iov, loff_t offset,
2095                                 unsigned long nr_segs);
2096 extern int ext4_ind_calc_metadata_amount(struct inode *inode, sector_t lblock);
2097 extern int ext4_ind_trans_blocks(struct inode *inode, int nrblocks);
2098 extern void ext4_ind_truncate(handle_t *, struct inode *inode);
2099 extern int ext4_free_hole_blocks(handle_t *handle, struct inode *inode,
2100                                  ext4_lblk_t first, ext4_lblk_t stop);
2101
2102 /* ioctl.c */
2103 extern long ext4_ioctl(struct file *, unsigned int, unsigned long);
2104 extern long ext4_compat_ioctl(struct file *, unsigned int, unsigned long);
2105
2106 /* migrate.c */
2107 extern int ext4_ext_migrate(struct inode *);
2108 extern int ext4_ind_migrate(struct inode *inode);
2109
2110 /* namei.c */
2111 extern int ext4_dirent_csum_verify(struct inode *inode,
2112                                    struct ext4_dir_entry *dirent);
2113 extern int ext4_orphan_add(handle_t *, struct inode *);
2114 extern int ext4_orphan_del(handle_t *, struct inode *);
2115 extern int ext4_htree_fill_tree(struct file *dir_file, __u32 start_hash,
2116                                 __u32 start_minor_hash, __u32 *next_hash);
2117 extern int search_dir(struct buffer_head *bh,
2118                       char *search_buf,
2119                       int buf_size,
2120                       struct inode *dir,
2121                       const struct qstr *d_name,
2122                       unsigned int offset,
2123                       struct ext4_dir_entry_2 **res_dir);
2124 extern int ext4_generic_delete_entry(handle_t *handle,
2125                                      struct inode *dir,
2126                                      struct ext4_dir_entry_2 *de_del,
2127                                      struct buffer_head *bh,
2128                                      void *entry_buf,
2129                                      int buf_size,
2130                                      int csum_size);
2131
2132 /* resize.c */
2133 extern int ext4_group_add(struct super_block *sb,
2134                                 struct ext4_new_group_data *input);
2135 extern int ext4_group_extend(struct super_block *sb,
2136                                 struct ext4_super_block *es,
2137                                 ext4_fsblk_t n_blocks_count);
2138 extern int ext4_resize_fs(struct super_block *sb, ext4_fsblk_t n_blocks_count);
2139
2140 /* super.c */
2141 extern int ext4_calculate_overhead(struct super_block *sb);
2142 extern int ext4_superblock_csum_verify(struct super_block *sb,
2143                                        struct ext4_super_block *es);
2144 extern void ext4_superblock_csum_set(struct super_block *sb);
2145 extern void *ext4_kvmalloc(size_t size, gfp_t flags);
2146 extern void *ext4_kvzalloc(size_t size, gfp_t flags);
2147 extern void ext4_kvfree(void *ptr);
2148 extern int ext4_alloc_flex_bg_array(struct super_block *sb,
2149                                     ext4_group_t ngroup);
2150 extern const char *ext4_decode_error(struct super_block *sb, int errno,
2151                                      char nbuf[16]);
2152 extern __printf(4, 5)
2153 void __ext4_error(struct super_block *, const char *, unsigned int,
2154                   const char *, ...);
2155 #define ext4_error(sb, message...)      __ext4_error(sb, __func__,      \
2156                                                      __LINE__, ## message)
2157 extern __printf(5, 6)
2158 void ext4_error_inode(struct inode *, const char *, unsigned int, ext4_fsblk_t,
2159                       const char *, ...);
2160 extern __printf(5, 6)
2161 void ext4_error_file(struct file *, const char *, unsigned int, ext4_fsblk_t,
2162                      const char *, ...);
2163 extern void __ext4_std_error(struct super_block *, const char *,
2164                              unsigned int, int);
2165 extern __printf(4, 5)
2166 void __ext4_abort(struct super_block *, const char *, unsigned int,
2167                   const char *, ...);
2168 #define ext4_abort(sb, message...)      __ext4_abort(sb, __func__, \
2169                                                        __LINE__, ## message)
2170 extern __printf(4, 5)
2171 void __ext4_warning(struct super_block *, const char *, unsigned int,
2172                     const char *, ...);
2173 #define ext4_warning(sb, message...)    __ext4_warning(sb, __func__, \
2174                                                        __LINE__, ## message)
2175 extern __printf(3, 4)
2176 void ext4_msg(struct super_block *, const char *, const char *, ...);
2177 extern void __dump_mmp_msg(struct super_block *, struct mmp_struct *mmp,
2178                            const char *, unsigned int, const char *);
2179 #define dump_mmp_msg(sb, mmp, msg)      __dump_mmp_msg(sb, mmp, __func__, \
2180                                                        __LINE__, msg)
2181 extern __printf(7, 8)
2182 void __ext4_grp_locked_error(const char *, unsigned int,
2183                              struct super_block *, ext4_group_t,
2184                              unsigned long, ext4_fsblk_t,
2185                              const char *, ...);
2186 #define ext4_grp_locked_error(sb, grp, message...) \
2187         __ext4_grp_locked_error(__func__, __LINE__, (sb), (grp), ## message)
2188 extern void ext4_update_dynamic_rev(struct super_block *sb);
2189 extern int ext4_update_compat_feature(handle_t *handle, struct super_block *sb,
2190                                         __u32 compat);
2191 extern int ext4_update_rocompat_feature(handle_t *handle,
2192                                         struct super_block *sb, __u32 rocompat);
2193 extern int ext4_update_incompat_feature(handle_t *handle,
2194                                         struct super_block *sb, __u32 incompat);
2195 extern ext4_fsblk_t ext4_block_bitmap(struct super_block *sb,
2196                                       struct ext4_group_desc *bg);
2197 extern ext4_fsblk_t ext4_inode_bitmap(struct super_block *sb,
2198                                       struct ext4_group_desc *bg);
2199 extern ext4_fsblk_t ext4_inode_table(struct super_block *sb,
2200                                      struct ext4_group_desc *bg);
2201 extern __u32 ext4_free_group_clusters(struct super_block *sb,
2202                                       struct ext4_group_desc *bg);
2203 extern __u32 ext4_free_inodes_count(struct super_block *sb,
2204                                  struct ext4_group_desc *bg);
2205 extern __u32 ext4_used_dirs_count(struct super_block *sb,
2206                                 struct ext4_group_desc *bg);
2207 extern __u32 ext4_itable_unused_count(struct super_block *sb,
2208                                    struct ext4_group_desc *bg);
2209 extern void ext4_block_bitmap_set(struct super_block *sb,
2210                                   struct ext4_group_desc *bg, ext4_fsblk_t blk);
2211 extern void ext4_inode_bitmap_set(struct super_block *sb,
2212                                   struct ext4_group_desc *bg, ext4_fsblk_t blk);
2213 extern void ext4_inode_table_set(struct super_block *sb,
2214                                  struct ext4_group_desc *bg, ext4_fsblk_t blk);
2215 extern void ext4_free_group_clusters_set(struct super_block *sb,
2216                                          struct ext4_group_desc *bg,
2217                                          __u32 count);
2218 extern void ext4_free_inodes_set(struct super_block *sb,
2219                                 struct ext4_group_desc *bg, __u32 count);
2220 extern void ext4_used_dirs_set(struct super_block *sb,
2221                                 struct ext4_group_desc *bg, __u32 count);
2222 extern void ext4_itable_unused_set(struct super_block *sb,
2223                                    struct ext4_group_desc *bg, __u32 count);
2224 extern int ext4_group_desc_csum_verify(struct super_block *sb, __u32 group,
2225                                        struct ext4_group_desc *gdp);
2226 extern void ext4_group_desc_csum_set(struct super_block *sb, __u32 group,
2227                                      struct ext4_group_desc *gdp);
2228 extern int ext4_register_li_request(struct super_block *sb,
2229                                     ext4_group_t first_not_zeroed);
2230
2231 static inline int ext4_has_group_desc_csum(struct super_block *sb)
2232 {
2233         return EXT4_HAS_RO_COMPAT_FEATURE(sb,
2234                                           EXT4_FEATURE_RO_COMPAT_GDT_CSUM |
2235                                           EXT4_FEATURE_RO_COMPAT_METADATA_CSUM);
2236 }
2237
2238 static inline ext4_fsblk_t ext4_blocks_count(struct ext4_super_block *es)
2239 {
2240         return ((ext4_fsblk_t)le32_to_cpu(es->s_blocks_count_hi) << 32) |
2241                 le32_to_cpu(es->s_blocks_count_lo);
2242 }
2243
2244 static inline ext4_fsblk_t ext4_r_blocks_count(struct ext4_super_block *es)
2245 {
2246         return ((ext4_fsblk_t)le32_to_cpu(es->s_r_blocks_count_hi) << 32) |
2247                 le32_to_cpu(es->s_r_blocks_count_lo);
2248 }
2249
2250 static inline ext4_fsblk_t ext4_free_blocks_count(struct ext4_super_block *es)
2251 {
2252         return ((ext4_fsblk_t)le32_to_cpu(es->s_free_blocks_count_hi) << 32) |
2253                 le32_to_cpu(es->s_free_blocks_count_lo);
2254 }
2255
2256 static inline void ext4_blocks_count_set(struct ext4_super_block *es,
2257                                          ext4_fsblk_t blk)
2258 {
2259         es->s_blocks_count_lo = cpu_to_le32((u32)blk);
2260         es->s_blocks_count_hi = cpu_to_le32(blk >> 32);
2261 }
2262
2263 static inline void ext4_free_blocks_count_set(struct ext4_super_block *es,
2264                                               ext4_fsblk_t blk)
2265 {
2266         es->s_free_blocks_count_lo = cpu_to_le32((u32)blk);
2267         es->s_free_blocks_count_hi = cpu_to_le32(blk >> 32);
2268 }
2269
2270 static inline void ext4_r_blocks_count_set(struct ext4_super_block *es,
2271                                            ext4_fsblk_t blk)
2272 {
2273         es->s_r_blocks_count_lo = cpu_to_le32((u32)blk);
2274         es->s_r_blocks_count_hi = cpu_to_le32(blk >> 32);
2275 }
2276
2277 static inline loff_t ext4_isize(struct ext4_inode *raw_inode)
2278 {
2279         if (S_ISREG(le16_to_cpu(raw_inode->i_mode)))
2280                 return ((loff_t)le32_to_cpu(raw_inode->i_size_high) << 32) |
2281                         le32_to_cpu(raw_inode->i_size_lo);
2282         else
2283                 return (loff_t) le32_to_cpu(raw_inode->i_size_lo);
2284 }
2285
2286 static inline void ext4_isize_set(struct ext4_inode *raw_inode, loff_t i_size)
2287 {
2288         raw_inode->i_size_lo = cpu_to_le32(i_size);
2289         raw_inode->i_size_high = cpu_to_le32(i_size >> 32);
2290 }
2291
2292 static inline
2293 struct ext4_group_info *ext4_get_group_info(struct super_block *sb,
2294                                             ext4_group_t group)
2295 {
2296          struct ext4_group_info ***grp_info;
2297          long indexv, indexh;
2298          grp_info = EXT4_SB(sb)->s_group_info;
2299          indexv = group >> (EXT4_DESC_PER_BLOCK_BITS(sb));
2300          indexh = group & ((EXT4_DESC_PER_BLOCK(sb)) - 1);
2301          return grp_info[indexv][indexh];
2302 }
2303
2304 /*
2305  * Reading s_groups_count requires using smp_rmb() afterwards.  See
2306  * the locking protocol documented in the comments of ext4_group_add()
2307  * in resize.c
2308  */
2309 static inline ext4_group_t ext4_get_groups_count(struct super_block *sb)
2310 {
2311         ext4_group_t    ngroups = EXT4_SB(sb)->s_groups_count;
2312
2313         smp_rmb();
2314         return ngroups;
2315 }
2316
2317 static inline ext4_group_t ext4_flex_group(struct ext4_sb_info *sbi,
2318                                              ext4_group_t block_group)
2319 {
2320         return block_group >> sbi->s_log_groups_per_flex;
2321 }
2322
2323 static inline unsigned int ext4_flex_bg_size(struct ext4_sb_info *sbi)
2324 {
2325         return 1 << sbi->s_log_groups_per_flex;
2326 }
2327
2328 #define ext4_std_error(sb, errno)                               \
2329 do {                                                            \
2330         if ((errno))                                            \
2331                 __ext4_std_error((sb), __func__, __LINE__, (errno));    \
2332 } while (0)
2333
2334 #ifdef CONFIG_SMP
2335 /* Each CPU can accumulate percpu_counter_batch clusters in their local
2336  * counters. So we need to make sure we have free clusters more
2337  * than percpu_counter_batch  * nr_cpu_ids. Also add a window of 4 times.
2338  */
2339 #define EXT4_FREECLUSTERS_WATERMARK (4 * (percpu_counter_batch * nr_cpu_ids))
2340 #else
2341 #define EXT4_FREECLUSTERS_WATERMARK 0
2342 #endif
2343
2344 static inline void ext4_update_i_disksize(struct inode *inode, loff_t newsize)
2345 {
2346         /*
2347          * XXX: replace with spinlock if seen contended -bzzz
2348          */
2349         down_write(&EXT4_I(inode)->i_data_sem);
2350         if (newsize > EXT4_I(inode)->i_disksize)
2351                 EXT4_I(inode)->i_disksize = newsize;
2352         up_write(&EXT4_I(inode)->i_data_sem);
2353         return ;
2354 }
2355
2356 struct ext4_group_info {
2357         unsigned long   bb_state;
2358         struct rb_root  bb_free_root;
2359         ext4_grpblk_t   bb_first_free;  /* first free block */
2360         ext4_grpblk_t   bb_free;        /* total free blocks */
2361         ext4_grpblk_t   bb_fragments;   /* nr of freespace fragments */
2362         ext4_grpblk_t   bb_largest_free_order;/* order of largest frag in BG */
2363         struct          list_head bb_prealloc_list;
2364 #ifdef DOUBLE_CHECK
2365         void            *bb_bitmap;
2366 #endif
2367         struct rw_semaphore alloc_sem;
2368         ext4_grpblk_t   bb_counters[];  /* Nr of free power-of-two-block
2369                                          * regions, index is order.
2370                                          * bb_counters[3] = 5 means
2371                                          * 5 free 8-block regions. */
2372 };
2373
2374 #define EXT4_GROUP_INFO_NEED_INIT_BIT           0
2375 #define EXT4_GROUP_INFO_WAS_TRIMMED_BIT         1
2376
2377 #define EXT4_MB_GRP_NEED_INIT(grp)      \
2378         (test_bit(EXT4_GROUP_INFO_NEED_INIT_BIT, &((grp)->bb_state)))
2379
2380 #define EXT4_MB_GRP_WAS_TRIMMED(grp)    \
2381         (test_bit(EXT4_GROUP_INFO_WAS_TRIMMED_BIT, &((grp)->bb_state)))
2382 #define EXT4_MB_GRP_SET_TRIMMED(grp)    \
2383         (set_bit(EXT4_GROUP_INFO_WAS_TRIMMED_BIT, &((grp)->bb_state)))
2384 #define EXT4_MB_GRP_CLEAR_TRIMMED(grp)  \
2385         (clear_bit(EXT4_GROUP_INFO_WAS_TRIMMED_BIT, &((grp)->bb_state)))
2386
2387 #define EXT4_MAX_CONTENTION             8
2388 #define EXT4_CONTENTION_THRESHOLD       2
2389
2390 static inline spinlock_t *ext4_group_lock_ptr(struct super_block *sb,
2391                                               ext4_group_t group)
2392 {
2393         return bgl_lock_ptr(EXT4_SB(sb)->s_blockgroup_lock, group);
2394 }
2395
2396 /*
2397  * Returns true if the filesystem is busy enough that attempts to
2398  * access the block group locks has run into contention.
2399  */
2400 static inline int ext4_fs_is_busy(struct ext4_sb_info *sbi)
2401 {
2402         return (atomic_read(&sbi->s_lock_busy) > EXT4_CONTENTION_THRESHOLD);
2403 }
2404
2405 static inline void ext4_lock_group(struct super_block *sb, ext4_group_t group)
2406 {
2407         spinlock_t *lock = ext4_group_lock_ptr(sb, group);
2408         if (spin_trylock(lock))
2409                 /*
2410                  * We're able to grab the lock right away, so drop the
2411                  * lock contention counter.
2412                  */
2413                 atomic_add_unless(&EXT4_SB(sb)->s_lock_busy, -1, 0);
2414         else {
2415                 /*
2416                  * The lock is busy, so bump the contention counter,
2417                  * and then wait on the spin lock.
2418                  */
2419                 atomic_add_unless(&EXT4_SB(sb)->s_lock_busy, 1,
2420                                   EXT4_MAX_CONTENTION);
2421                 spin_lock(lock);
2422         }
2423 }
2424
2425 static inline void ext4_unlock_group(struct super_block *sb,
2426                                         ext4_group_t group)
2427 {
2428         spin_unlock(ext4_group_lock_ptr(sb, group));
2429 }
2430
2431 /*
2432  * Block validity checking
2433  */
2434 #define ext4_check_indirect_blockref(inode, bh)                         \
2435         ext4_check_blockref(__func__, __LINE__, inode,                  \
2436                             (__le32 *)(bh)->b_data,                     \
2437                             EXT4_ADDR_PER_BLOCK((inode)->i_sb))
2438
2439 #define ext4_ind_check_inode(inode)                                     \
2440         ext4_check_blockref(__func__, __LINE__, inode,                  \
2441                             EXT4_I(inode)->i_data,                      \
2442                             EXT4_NDIR_BLOCKS)
2443
2444 /*
2445  * Inodes and files operations
2446  */
2447
2448 /* dir.c */
2449 extern const struct file_operations ext4_dir_operations;
2450
2451 /* file.c */
2452 extern const struct inode_operations ext4_file_inode_operations;
2453 extern const struct file_operations ext4_file_operations;
2454 extern loff_t ext4_llseek(struct file *file, loff_t offset, int origin);
2455 extern void ext4_unwritten_wait(struct inode *inode);
2456
2457 /* inline.c */
2458 extern int ext4_has_inline_data(struct inode *inode);
2459 extern int ext4_get_inline_size(struct inode *inode);
2460 extern int ext4_get_max_inline_size(struct inode *inode);
2461 extern int ext4_find_inline_data_nolock(struct inode *inode);
2462 extern void ext4_write_inline_data(struct inode *inode,
2463                                    struct ext4_iloc *iloc,
2464                                    void *buffer, loff_t pos,
2465                                    unsigned int len);
2466 extern int ext4_prepare_inline_data(handle_t *handle, struct inode *inode,
2467                                     unsigned int len);
2468 extern int ext4_init_inline_data(handle_t *handle, struct inode *inode,
2469                                  unsigned int len);
2470 extern int ext4_destroy_inline_data(handle_t *handle, struct inode *inode);
2471
2472 extern int ext4_readpage_inline(struct inode *inode, struct page *page);
2473 extern int ext4_try_to_write_inline_data(struct address_space *mapping,
2474                                          struct inode *inode,
2475                                          loff_t pos, unsigned len,
2476                                          unsigned flags,
2477                                          struct page **pagep);
2478 extern int ext4_write_inline_data_end(struct inode *inode,
2479                                       loff_t pos, unsigned len,
2480                                       unsigned copied,
2481                                       struct page *page);
2482 extern struct buffer_head *
2483 ext4_journalled_write_inline_data(struct inode *inode,
2484                                   unsigned len,
2485                                   struct page *page);
2486 extern int ext4_da_write_inline_data_begin(struct address_space *mapping,
2487                                            struct inode *inode,
2488                                            loff_t pos, unsigned len,
2489                                            unsigned flags,
2490                                            struct page **pagep,
2491                                            void **fsdata);
2492 extern int ext4_da_write_inline_data_end(struct inode *inode, loff_t pos,
2493                                          unsigned len, unsigned copied,
2494                                          struct page *page);
2495 extern int ext4_try_add_inline_entry(handle_t *handle, struct dentry *dentry,
2496                                      struct inode *inode);
2497 extern int ext4_try_create_inline_dir(handle_t *handle,
2498                                       struct inode *parent,
2499                                       struct inode *inode);
2500 extern int ext4_read_inline_dir(struct file *filp,
2501                                 void *dirent, filldir_t filldir,
2502                                 int *has_inline_data);
2503 extern int htree_inlinedir_to_tree(struct file *dir_file,
2504                                    struct inode *dir, ext4_lblk_t block,
2505                                    struct dx_hash_info *hinfo,
2506                                    __u32 start_hash, __u32 start_minor_hash,
2507                                    int *has_inline_data);
2508 extern struct buffer_head *ext4_find_inline_entry(struct inode *dir,
2509                                         const struct qstr *d_name,
2510                                         struct ext4_dir_entry_2 **res_dir,
2511                                         int *has_inline_data);
2512 extern int ext4_delete_inline_entry(handle_t *handle,
2513                                     struct inode *dir,
2514                                     struct ext4_dir_entry_2 *de_del,
2515                                     struct buffer_head *bh,
2516                                     int *has_inline_data);
2517 extern int empty_inline_dir(struct inode *dir, int *has_inline_data);
2518 extern struct buffer_head *ext4_get_first_inline_block(struct inode *inode,
2519                                         struct ext4_dir_entry_2 **parent_de,
2520                                         int *retval);
2521 extern int ext4_inline_data_fiemap(struct inode *inode,
2522                                    struct fiemap_extent_info *fieinfo,
2523                                    int *has_inline);
2524 extern int ext4_try_to_evict_inline_data(handle_t *handle,
2525                                          struct inode *inode,
2526                                          int needed);
2527 extern void ext4_inline_data_truncate(struct inode *inode, int *has_inline);
2528
2529 extern int ext4_convert_inline_data(struct inode *inode);
2530
2531 /* namei.c */
2532 extern const struct inode_operations ext4_dir_inode_operations;
2533 extern const struct inode_operations ext4_special_inode_operations;
2534 extern struct dentry *ext4_get_parent(struct dentry *child);
2535 extern struct ext4_dir_entry_2 *ext4_init_dot_dotdot(struct inode *inode,
2536                                  struct ext4_dir_entry_2 *de,
2537                                  int blocksize, int csum_size,
2538                                  unsigned int parent_ino, int dotdot_real_len);
2539 extern void initialize_dirent_tail(struct ext4_dir_entry_tail *t,
2540                                    unsigned int blocksize);
2541 extern int ext4_handle_dirty_dirent_node(handle_t *handle,
2542                                          struct inode *inode,
2543                                          struct buffer_head *bh);
2544 #define S_SHIFT 12
2545 static unsigned char ext4_type_by_mode[S_IFMT >> S_SHIFT] = {
2546         [S_IFREG >> S_SHIFT]    = EXT4_FT_REG_FILE,
2547         [S_IFDIR >> S_SHIFT]    = EXT4_FT_DIR,
2548         [S_IFCHR >> S_SHIFT]    = EXT4_FT_CHRDEV,
2549         [S_IFBLK >> S_SHIFT]    = EXT4_FT_BLKDEV,
2550         [S_IFIFO >> S_SHIFT]    = EXT4_FT_FIFO,
2551         [S_IFSOCK >> S_SHIFT]   = EXT4_FT_SOCK,
2552         [S_IFLNK >> S_SHIFT]    = EXT4_FT_SYMLINK,
2553 };
2554
2555 static inline void ext4_set_de_type(struct super_block *sb,
2556                                 struct ext4_dir_entry_2 *de,
2557                                 umode_t mode) {
2558         if (EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_FILETYPE))
2559                 de->file_type = ext4_type_by_mode[(mode & S_IFMT)>>S_SHIFT];
2560 }
2561
2562
2563 /* symlink.c */
2564 extern const struct inode_operations ext4_symlink_inode_operations;
2565 extern const struct inode_operations ext4_fast_symlink_inode_operations;
2566
2567 /* block_validity */
2568 extern void ext4_release_system_zone(struct super_block *sb);
2569 extern int ext4_setup_system_zone(struct super_block *sb);
2570 extern int __init ext4_init_system_zone(void);
2571 extern void ext4_exit_system_zone(void);
2572 extern int ext4_data_block_valid(struct ext4_sb_info *sbi,
2573                                  ext4_fsblk_t start_blk,
2574                                  unsigned int count);
2575 extern int ext4_check_blockref(const char *, unsigned int,
2576                                struct inode *, __le32 *, unsigned int);
2577
2578 /* extents.c */
2579 struct ext4_ext_path;
2580 struct ext4_extent;
2581
2582 extern int ext4_ext_tree_init(handle_t *handle, struct inode *);
2583 extern int ext4_ext_writepage_trans_blocks(struct inode *, int);
2584 extern int ext4_ext_index_trans_blocks(struct inode *inode, int extents);
2585 extern int ext4_ext_map_blocks(handle_t *handle, struct inode *inode,
2586                                struct ext4_map_blocks *map, int flags);
2587 extern void ext4_ext_truncate(handle_t *, struct inode *);
2588 extern int ext4_ext_remove_space(struct inode *inode, ext4_lblk_t start,
2589                                  ext4_lblk_t end);
2590 extern void ext4_ext_init(struct super_block *);
2591 extern void ext4_ext_release(struct super_block *);
2592 extern long ext4_fallocate(struct file *file, int mode, loff_t offset,
2593                           loff_t len);
2594 extern int ext4_convert_unwritten_extents(struct inode *inode, loff_t offset,
2595                           ssize_t len);
2596 extern int ext4_map_blocks(handle_t *handle, struct inode *inode,
2597                            struct ext4_map_blocks *map, int flags);
2598 extern int ext4_ext_calc_metadata_amount(struct inode *inode,
2599                                          ext4_lblk_t lblocks);
2600 extern int ext4_extent_tree_init(handle_t *, struct inode *);
2601 extern int ext4_ext_calc_credits_for_single_extent(struct inode *inode,
2602                                                    int num,
2603                                                    struct ext4_ext_path *path);
2604 extern int ext4_can_extents_be_merged(struct inode *inode,
2605                                       struct ext4_extent *ex1,
2606                                       struct ext4_extent *ex2);
2607 extern int ext4_ext_insert_extent(handle_t *, struct inode *,
2608                                   struct ext4_ext_path *,
2609                                   struct ext4_extent *, int);
2610 extern struct ext4_ext_path *ext4_ext_find_extent(struct inode *, ext4_lblk_t,
2611                                                   struct ext4_ext_path *);
2612 extern void ext4_ext_drop_refs(struct ext4_ext_path *);
2613 extern int ext4_ext_check_inode(struct inode *inode);
2614 extern int ext4_find_delalloc_range(struct inode *inode,
2615                                     ext4_lblk_t lblk_start,
2616                                     ext4_lblk_t lblk_end);
2617 extern int ext4_find_delalloc_cluster(struct inode *inode, ext4_lblk_t lblk);
2618 extern int ext4_fiemap(struct inode *inode, struct fiemap_extent_info *fieinfo,
2619                         __u64 start, __u64 len);
2620
2621
2622 /* move_extent.c */
2623 extern void ext4_double_down_write_data_sem(struct inode *first,
2624                                             struct inode *second);
2625 extern void ext4_double_up_write_data_sem(struct inode *orig_inode,
2626                                           struct inode *donor_inode);
2627 void ext4_inode_double_lock(struct inode *inode1, struct inode *inode2);
2628 void ext4_inode_double_unlock(struct inode *inode1, struct inode *inode2);
2629 extern int ext4_move_extents(struct file *o_filp, struct file *d_filp,
2630                              __u64 start_orig, __u64 start_donor,
2631                              __u64 len, __u64 *moved_len);
2632
2633 /* page-io.c */
2634 extern int __init ext4_init_pageio(void);
2635 extern void ext4_exit_pageio(void);
2636 extern void ext4_ioend_shutdown(struct inode *);
2637 extern ext4_io_end_t *ext4_init_io_end(struct inode *inode, gfp_t flags);
2638 extern ext4_io_end_t *ext4_get_io_end(ext4_io_end_t *io_end);
2639 extern int ext4_put_io_end(ext4_io_end_t *io_end);
2640 extern void ext4_put_io_end_defer(ext4_io_end_t *io_end);
2641 extern void ext4_io_submit_init(struct ext4_io_submit *io,
2642                                 struct writeback_control *wbc);
2643 extern void ext4_end_io_work(struct work_struct *work);
2644 extern void ext4_io_submit(struct ext4_io_submit *io);
2645 extern int ext4_bio_write_page(struct ext4_io_submit *io,
2646                                struct page *page,
2647                                int len,
2648                                struct writeback_control *wbc);
2649
2650 /* mmp.c */
2651 extern int ext4_multi_mount_protect(struct super_block *, ext4_fsblk_t);
2652 extern void ext4_mmp_csum_set(struct super_block *sb, struct mmp_struct *mmp);
2653 extern int ext4_mmp_csum_verify(struct super_block *sb,
2654                                 struct mmp_struct *mmp);
2655
2656 /*
2657  * Note that these flags will never ever appear in a buffer_head's state flag.
2658  * See EXT4_MAP_... to see where this is used.
2659  */
2660 enum ext4_state_bits {
2661         BH_Uninit       /* blocks are allocated but uninitialized on disk */
2662          = BH_JBDPrivateStart,
2663         BH_AllocFromCluster,    /* allocated blocks were part of already
2664                                  * allocated cluster. */
2665 };
2666
2667 /*
2668  * Add new method to test whether block and inode bitmaps are properly
2669  * initialized. With uninit_bg reading the block from disk is not enough
2670  * to mark the bitmap uptodate. We need to also zero-out the bitmap
2671  */
2672 #define BH_BITMAP_UPTODATE BH_JBDPrivateStart
2673
2674 static inline int bitmap_uptodate(struct buffer_head *bh)
2675 {
2676         return (buffer_uptodate(bh) &&
2677                         test_bit(BH_BITMAP_UPTODATE, &(bh)->b_state));
2678 }
2679 static inline void set_bitmap_uptodate(struct buffer_head *bh)
2680 {
2681         set_bit(BH_BITMAP_UPTODATE, &(bh)->b_state);
2682 }
2683
2684 /*
2685  * Disable DIO read nolock optimization, so new dioreaders will be forced
2686  * to grab i_mutex
2687  */
2688 static inline void ext4_inode_block_unlocked_dio(struct inode *inode)
2689 {
2690         ext4_set_inode_state(inode, EXT4_STATE_DIOREAD_LOCK);
2691         smp_mb();
2692 }
2693 static inline void ext4_inode_resume_unlocked_dio(struct inode *inode)
2694 {
2695         smp_mb();
2696         ext4_clear_inode_state(inode, EXT4_STATE_DIOREAD_LOCK);
2697 }
2698
2699 #define in_range(b, first, len) ((b) >= (first) && (b) <= (first) + (len) - 1)
2700
2701 /* For ioend & aio unwritten conversion wait queues */
2702 #define EXT4_WQ_HASH_SZ         37
2703 #define ext4_ioend_wq(v)   (&ext4__ioend_wq[((unsigned long)(v)) %\
2704                                             EXT4_WQ_HASH_SZ])
2705 #define ext4_aio_mutex(v)  (&ext4__aio_mutex[((unsigned long)(v)) %\
2706                                              EXT4_WQ_HASH_SZ])
2707 extern wait_queue_head_t ext4__ioend_wq[EXT4_WQ_HASH_SZ];
2708 extern struct mutex ext4__aio_mutex[EXT4_WQ_HASH_SZ];
2709
2710 #define EXT4_RESIZING   0
2711 extern int ext4_resize_begin(struct super_block *sb);
2712 extern void ext4_resize_end(struct super_block *sb);
2713
2714 #endif  /* __KERNEL__ */
2715
2716 #endif  /* _EXT4_H */