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 #define EXT4_ERROR_INODE(inode, fmt, a...) \
  61         ext4_error_inode((inode), __func__, __LINE__, 0, (fmt), ## a)
  62
  63 #define EXT4_ERROR_INODE_BLOCK(inode, block, fmt, a...)                 \
  64         ext4_error_inode((inode), __func__, __LINE__, (block), (fmt), ## a)
  65
  66 #define EXT4_ERROR_FILE(file, block, fmt, a...)                         \
  67         ext4_error_file((file), __func__, __LINE__, (block), (fmt), ## a)
  68
  69 /* data type for block offset of block group */
  70 typedef int ext4_grpblk_t;
  71
  72 /* data type for filesystem-wide blocks number */
  73 typedef unsigned long long ext4_fsblk_t;
  74
  75 /* data type for file logical block number */
  76 typedef __u32 ext4_lblk_t;
  77
  78 /* data type for block group number */
  79 typedef unsigned int ext4_group_t;
  80
  81 /*
  82  * Flags used in mballoc's allocation_context flags field.
  83  *
  84  * Also used to show what's going on for debugging purposes when the
  85  * flag field is exported via the traceport interface
  86  */
  87
  88 /* prefer goal again. length */
  89 #define EXT4_MB_HINT_MERGE              0x0001
  90 /* blocks already reserved */
  91 #define EXT4_MB_HINT_RESERVED           0x0002
  92 /* metadata is being allocated */
  93 #define EXT4_MB_HINT_METADATA           0x0004
  94 /* first blocks in the file */
  95 #define EXT4_MB_HINT_FIRST              0x0008
  96 /* search for the best chunk */
  97 #define EXT4_MB_HINT_BEST               0x0010
  98 /* data is being allocated */
  99 #define EXT4_MB_HINT_DATA               0x0020
 100 /* don't preallocate (for tails) */
 101 #define EXT4_MB_HINT_NOPREALLOC         0x0040
 102 /* allocate for locality group */
 103 #define EXT4_MB_HINT_GROUP_ALLOC        0x0080
 104 /* allocate goal blocks or none */
 105 #define EXT4_MB_HINT_GOAL_ONLY          0x0100
 106 /* goal is meaningful */
 107 #define EXT4_MB_HINT_TRY_GOAL           0x0200
 108 /* blocks already pre-reserved by delayed allocation */
 109 #define EXT4_MB_DELALLOC_RESERVED       0x0400
 110 /* We are doing stream allocation */
 111 #define EXT4_MB_STREAM_ALLOC            0x0800
 112 /* Use reserved root blocks if needed */
 113 #define EXT4_MB_USE_ROOT_BLOCKS         0x1000
 114
 115 struct ext4_allocation_request {
 116         /* target inode for block we're allocating */
 117         struct inode *inode;
 118         /* how many blocks we want to allocate */
 119         unsigned int len;
 120         /* logical block in target inode */
 121         ext4_lblk_t logical;
 122         /* the closest logical allocated block to the left */
 123         ext4_lblk_t lleft;
 124         /* the closest logical allocated block to the right */
 125         ext4_lblk_t lright;
 126         /* phys. target (a hint) */
 127         ext4_fsblk_t goal;
 128         /* phys. block for the closest logical allocated block to the left */
 129         ext4_fsblk_t pleft;
 130         /* phys. block for the closest logical allocated block to the right */
 131         ext4_fsblk_t pright;
 132         /* flags. see above EXT4_MB_HINT_* */
 133         unsigned int flags;
 134 };
 135
 136 /*
 137  * Logical to physical block mapping, used by ext4_map_blocks()
 138  *
 139  * This structure is used to pass requests into ext4_map_blocks() as
 140  * well as to store the information returned by ext4_map_blocks().  It
 141  * takes less room on the stack than a struct buffer_head.
 142  */
 143 #define EXT4_MAP_NEW            (1 << BH_New)
 144 #define EXT4_MAP_MAPPED         (1 << BH_Mapped)
 145 #define EXT4_MAP_UNWRITTEN      (1 << BH_Unwritten)
 146 #define EXT4_MAP_BOUNDARY       (1 << BH_Boundary)
 147 #define EXT4_MAP_UNINIT         (1 << BH_Uninit)
 148 /* Sometimes (in the bigalloc case, from ext4_da_get_block_prep) the caller of
 149  * ext4_map_blocks wants to know whether or not the underlying cluster has
 150  * already been accounted for. EXT4_MAP_FROM_CLUSTER conveys to the caller that
 151  * the requested mapping was from previously mapped (or delayed allocated)
 152  * cluster. We use BH_AllocFromCluster only for this flag. BH_AllocFromCluster
 153  * should never appear on buffer_head's state flags.
 154  */
 155 #define EXT4_MAP_FROM_CLUSTER   (1 << BH_AllocFromCluster)
 156 #define EXT4_MAP_FLAGS          (EXT4_MAP_NEW | EXT4_MAP_MAPPED |\
 157                                  EXT4_MAP_UNWRITTEN | EXT4_MAP_BOUNDARY |\
 158                                  EXT4_MAP_UNINIT | EXT4_MAP_FROM_CLUSTER)
 159
 160 struct ext4_map_blocks {
 161         ext4_fsblk_t m_pblk;
 162         ext4_lblk_t m_lblk;
 163         unsigned int m_len;
 164         unsigned int m_flags;
 165 };
 166
 167 /*
 168  * For delayed allocation tracking
 169  */
 170 struct mpage_da_data {
 171         struct inode *inode;
 172         sector_t b_blocknr;             /* start block number of extent */
 173         size_t b_size;                  /* size of extent */
 174         unsigned long b_state;          /* state of the extent */
 175         unsigned long first_page, next_page;    /* extent of pages */
 176         struct writeback_control *wbc;
 177         int io_done;
 178         int pages_written;
 179         int retval;
 180 };
 181
 182 /*
 183  * Flags for ext4_io_end->flags
 184  */
 185 #define EXT4_IO_END_UNWRITTEN   0x0001
 186 #define EXT4_IO_END_ERROR       0x0002
 187 #define EXT4_IO_END_QUEUED      0x0004
 188 #define EXT4_IO_END_DIRECT      0x0008
 189
 190 struct ext4_io_page {
 191         struct page     *p_page;
 192         atomic_t        p_count;
 193 };
 194
 195 #define MAX_IO_PAGES 128
 196
 197 /*
 198  * For converting uninitialized extents on a work queue.
 199  *
 200  * 'page' is only used from the writepage() path; 'pages' is only used for
 201  * buffered writes; they are used to keep page references until conversion
 202  * takes place.  For AIO/DIO, neither field is filled in.
 203  */
 204 typedef struct ext4_io_end {
 205         struct list_head        list;           /* per-file finished IO list */
 206         struct inode            *inode;         /* file being written to */
 207         unsigned int            flag;           /* unwritten or not */
 208         struct page             *page;          /* for writepage() path */
 209         loff_t                  offset;         /* offset in the file */
 210         ssize_t                 size;           /* size of the extent */
 211         struct work_struct      work;           /* data work queue */
 212         struct kiocb            *iocb;          /* iocb struct for AIO */
 213         int                     result;         /* error value for AIO */
 214         int                     num_io_pages;   /* for writepages() */
 215         struct ext4_io_page     *pages[MAX_IO_PAGES]; /* for writepages() */
 216 } ext4_io_end_t;
 217
 218 struct ext4_io_submit {
 219         int                     io_op;
 220         struct bio              *io_bio;
 221         ext4_io_end_t           *io_end;
 222         struct ext4_io_page     *io_page;
 223         sector_t                io_next_block;
 224 };
 225
 226 /*
 227  * Special inodes numbers
 228  */
 229 #define EXT4_BAD_INO             1      /* Bad blocks inode */
 230 #define EXT4_ROOT_INO            2      /* Root inode */
 231 #define EXT4_USR_QUOTA_INO       3      /* User quota inode */
 232 #define EXT4_GRP_QUOTA_INO       4      /* Group quota inode */
 233 #define EXT4_BOOT_LOADER_INO     5      /* Boot loader inode */
 234 #define EXT4_UNDEL_DIR_INO       6      /* Undelete directory inode */
 235 #define EXT4_RESIZE_INO          7      /* Reserved group descriptors inode */
 236 #define EXT4_JOURNAL_INO         8      /* Journal inode */
 237
 238 /* First non-reserved inode for old ext4 filesystems */
 239 #define EXT4_GOOD_OLD_FIRST_INO 11
 240
 241 /*
 242  * Maximal count of links to a file
 243  */
 244 #define EXT4_LINK_MAX           65000
 245
 246 /*
 247  * Macro-instructions used to manage several block sizes
 248  */
 249 #define EXT4_MIN_BLOCK_SIZE             1024
 250 #define EXT4_MAX_BLOCK_SIZE             65536
 251 #define EXT4_MIN_BLOCK_LOG_SIZE         10
 252 #define EXT4_MAX_BLOCK_LOG_SIZE         16
 253 #ifdef __KERNEL__
 254 # define EXT4_BLOCK_SIZE(s)             ((s)->s_blocksize)
 255 #else
 256 # define EXT4_BLOCK_SIZE(s)             (EXT4_MIN_BLOCK_SIZE << (s)->s_log_block_size)
 257 #endif
 258 #define EXT4_ADDR_PER_BLOCK(s)          (EXT4_BLOCK_SIZE(s) / sizeof(__u32))
 259 #define EXT4_CLUSTER_SIZE(s)            (EXT4_BLOCK_SIZE(s) << \
 260                                          EXT4_SB(s)->s_cluster_bits)
 261 #ifdef __KERNEL__
 262 # define EXT4_BLOCK_SIZE_BITS(s)        ((s)->s_blocksize_bits)
 263 # define EXT4_CLUSTER_BITS(s)           (EXT4_SB(s)->s_cluster_bits)
 264 #else
 265 # define EXT4_BLOCK_SIZE_BITS(s)        ((s)->s_log_block_size + 10)
 266 #endif
 267 #ifdef __KERNEL__
 268 #define EXT4_ADDR_PER_BLOCK_BITS(s)     (EXT4_SB(s)->s_addr_per_block_bits)
 269 #define EXT4_INODE_SIZE(s)              (EXT4_SB(s)->s_inode_size)
 270 #define EXT4_FIRST_INO(s)               (EXT4_SB(s)->s_first_ino)
 271 #else
 272 #define EXT4_INODE_SIZE(s)      (((s)->s_rev_level == EXT4_GOOD_OLD_REV) ? \
 273                                  EXT4_GOOD_OLD_INODE_SIZE : \
 274                                  (s)->s_inode_size)
 275 #define EXT4_FIRST_INO(s)       (((s)->s_rev_level == EXT4_GOOD_OLD_REV) ? \
 276                                  EXT4_GOOD_OLD_FIRST_INO : \
 277                                  (s)->s_first_ino)
 278 #endif
 279 #define EXT4_BLOCK_ALIGN(size, blkbits)         ALIGN((size), (1 << (blkbits)))
 280
 281 /* Translate a block number to a cluster number */
 282 #define EXT4_B2C(sbi, blk)      ((blk) >> (sbi)->s_cluster_bits)
 283 /* Translate a cluster number to a block number */
 284 #define EXT4_C2B(sbi, cluster)  ((cluster) << (sbi)->s_cluster_bits)
 285 /* Translate # of blks to # of clusters */
 286 #define EXT4_NUM_B2C(sbi, blks) (((blks) + (sbi)->s_cluster_ratio - 1) >> \
 287                                  (sbi)->s_cluster_bits)
 288
 289 /*
 290  * Structure of a blocks group descriptor
 291  */
 292 struct ext4_group_desc
 293 {
 294         __le32  bg_block_bitmap_lo;     /* Blocks bitmap block */
 295         __le32  bg_inode_bitmap_lo;     /* Inodes bitmap block */
 296         __le32  bg_inode_table_lo;      /* Inodes table block */
 297         __le16  bg_free_blocks_count_lo;/* Free blocks count */
 298         __le16  bg_free_inodes_count_lo;/* Free inodes count */
 299         __le16  bg_used_dirs_count_lo;  /* Directories count */
 300         __le16  bg_flags;               /* EXT4_BG_flags (INODE_UNINIT, etc) */
 301         __le32  bg_exclude_bitmap_lo;   /* Exclude bitmap for snapshots */
 302         __le16  bg_block_bitmap_csum_lo;/* crc32c(s_uuid+grp_num+bbitmap) LE */
 303         __le16  bg_inode_bitmap_csum_lo;/* crc32c(s_uuid+grp_num+ibitmap) LE */
 304         __le16  bg_itable_unused_lo;    /* Unused inodes count */
 305         __le16  bg_checksum;            /* crc16(sb_uuid+group+desc) */
 306         __le32  bg_block_bitmap_hi;     /* Blocks bitmap block MSB */
 307         __le32  bg_inode_bitmap_hi;     /* Inodes bitmap block MSB */
 308         __le32  bg_inode_table_hi;      /* Inodes table block MSB */
 309         __le16  bg_free_blocks_count_hi;/* Free blocks count MSB */
 310         __le16  bg_free_inodes_count_hi;/* Free inodes count MSB */
 311         __le16  bg_used_dirs_count_hi;  /* Directories count MSB */
 312         __le16  bg_itable_unused_hi;    /* Unused inodes count MSB */
 313         __le32  bg_exclude_bitmap_hi;   /* Exclude bitmap block MSB */
 314         __le16  bg_block_bitmap_csum_hi;/* crc32c(s_uuid+grp_num+bbitmap) BE */
 315         __le16  bg_inode_bitmap_csum_hi;/* crc32c(s_uuid+grp_num+ibitmap) BE */
 316         __u32   bg_reserved;
 317 };
 318
 319 #define EXT4_BG_INODE_BITMAP_CSUM_HI_END        \
 320         (offsetof(struct ext4_group_desc, bg_inode_bitmap_csum_hi) + \
 321          sizeof(__le16))
 322 #define EXT4_BG_BLOCK_BITMAP_CSUM_HI_END        \
 323         (offsetof(struct ext4_group_desc, bg_block_bitmap_csum_hi) + \
 324          sizeof(__le16))
 325
 326 /*
 327  * Structure of a flex block group info
 328  */
 329
 330 struct flex_groups {
 331         atomic_t free_inodes;
 332         atomic_t free_clusters;
 333         atomic_t used_dirs;
 334 };
 335
 336 #define EXT4_BG_INODE_UNINIT    0x0001 /* Inode table/bitmap not in use */
 337 #define EXT4_BG_BLOCK_UNINIT    0x0002 /* Block bitmap not in use */
 338 #define EXT4_BG_INODE_ZEROED    0x0004 /* On-disk itable initialized to zero */
 339
 340 /*
 341  * Macro-instructions used to manage group descriptors
 342  */
 343 #define EXT4_MIN_DESC_SIZE              32
 344 #define EXT4_MIN_DESC_SIZE_64BIT        64
 345 #define EXT4_MAX_DESC_SIZE              EXT4_MIN_BLOCK_SIZE
 346 #define EXT4_DESC_SIZE(s)               (EXT4_SB(s)->s_desc_size)
 347 #ifdef __KERNEL__
 348 # define EXT4_BLOCKS_PER_GROUP(s)       (EXT4_SB(s)->s_blocks_per_group)
 349 # define EXT4_CLUSTERS_PER_GROUP(s)     (EXT4_SB(s)->s_clusters_per_group)
 350 # define EXT4_DESC_PER_BLOCK(s)         (EXT4_SB(s)->s_desc_per_block)
 351 # define EXT4_INODES_PER_GROUP(s)       (EXT4_SB(s)->s_inodes_per_group)
 352 # define EXT4_DESC_PER_BLOCK_BITS(s)    (EXT4_SB(s)->s_desc_per_block_bits)
 353 #else
 354 # define EXT4_BLOCKS_PER_GROUP(s)       ((s)->s_blocks_per_group)
 355 # define EXT4_DESC_PER_BLOCK(s)         (EXT4_BLOCK_SIZE(s) / EXT4_DESC_SIZE(s))
 356 # define EXT4_INODES_PER_GROUP(s)       ((s)->s_inodes_per_group)
 357 #endif
 358
 359 /*
 360  * Constants relative to the data blocks
 361  */
 362 #define EXT4_NDIR_BLOCKS                12
 363 #define EXT4_IND_BLOCK                  EXT4_NDIR_BLOCKS
 364 #define EXT4_DIND_BLOCK                 (EXT4_IND_BLOCK + 1)
 365 #define EXT4_TIND_BLOCK                 (EXT4_DIND_BLOCK + 1)
 366 #define EXT4_N_BLOCKS                   (EXT4_TIND_BLOCK + 1)
 367
 368 /*
 369  * Inode flags
 370  */
 371 #define EXT4_SECRM_FL                   0x00000001 /* Secure deletion */
 372 #define EXT4_UNRM_FL                    0x00000002 /* Undelete */
 373 #define EXT4_COMPR_FL                   0x00000004 /* Compress file */
 374 #define EXT4_SYNC_FL                    0x00000008 /* Synchronous updates */
 375 #define EXT4_IMMUTABLE_FL               0x00000010 /* Immutable file */
 376 #define EXT4_APPEND_FL                  0x00000020 /* writes to file may only append */
 377 #define EXT4_NODUMP_FL                  0x00000040 /* do not dump file */
 378 #define EXT4_NOATIME_FL                 0x00000080 /* do not update atime */
 379 /* Reserved for compression usage... */
 380 #define EXT4_DIRTY_FL                   0x00000100
 381 #define EXT4_COMPRBLK_FL                0x00000200 /* One or more compressed clusters */
 382 #define EXT4_NOCOMPR_FL                 0x00000400 /* Don't compress */
 383 #define EXT4_ECOMPR_FL                  0x00000800 /* Compression error */
 384 /* End compression flags --- maybe not all used */
 385 #define EXT4_INDEX_FL                   0x00001000 /* hash-indexed directory */
 386 #define EXT4_IMAGIC_FL                  0x00002000 /* AFS directory */
 387 #define EXT4_JOURNAL_DATA_FL            0x00004000 /* file data should be journaled */
 388 #define EXT4_NOTAIL_FL                  0x00008000 /* file tail should not be merged */
 389 #define EXT4_DIRSYNC_FL                 0x00010000 /* dirsync behaviour (directories only) */
 390 #define EXT4_TOPDIR_FL                  0x00020000 /* Top of directory hierarchies*/
 391 #define EXT4_HUGE_FILE_FL               0x00040000 /* Set to each huge file */
 392 #define EXT4_EXTENTS_FL                 0x00080000 /* Inode uses extents */
 393 #define EXT4_EA_INODE_FL                0x00200000 /* Inode used for large EA */
 394 #define EXT4_EOFBLOCKS_FL               0x00400000 /* Blocks allocated beyond EOF */
 395 #define EXT4_RESERVED_FL                0x80000000 /* reserved for ext4 lib */
 396
 397 #define EXT4_FL_USER_VISIBLE            0x004BDFFF /* User visible flags */
 398 #define EXT4_FL_USER_MODIFIABLE         0x004B80FF /* User modifiable flags */
 399
 400 /* Flags that should be inherited by new inodes from their parent. */
 401 #define EXT4_FL_INHERITED (EXT4_SECRM_FL | EXT4_UNRM_FL | EXT4_COMPR_FL |\
 402                            EXT4_SYNC_FL | EXT4_NODUMP_FL | EXT4_NOATIME_FL |\
 403                            EXT4_NOCOMPR_FL | EXT4_JOURNAL_DATA_FL |\
 404                            EXT4_NOTAIL_FL | EXT4_DIRSYNC_FL)
 405
 406 /* Flags that are appropriate for regular files (all but dir-specific ones). */
 407 #define EXT4_REG_FLMASK (~(EXT4_DIRSYNC_FL | EXT4_TOPDIR_FL))
 408
 409 /* Flags that are appropriate for non-directories/regular files. */
 410 #define EXT4_OTHER_FLMASK (EXT4_NODUMP_FL | EXT4_NOATIME_FL)
 411
 412 /* Mask out flags that are inappropriate for the given type of inode. */
 413 static inline __u32 ext4_mask_flags(umode_t mode, __u32 flags)
 414 {
 415         if (S_ISDIR(mode))
 416                 return flags;
 417         else if (S_ISREG(mode))
 418                 return flags & EXT4_REG_FLMASK;
 419         else
 420                 return flags & EXT4_OTHER_FLMASK;
 421 }
 422
 423 /*
 424  * Inode flags used for atomic set/get
 425  */
 426 enum {
 427         EXT4_INODE_SECRM        = 0,    /* Secure deletion */
 428         EXT4_INODE_UNRM         = 1,    /* Undelete */
 429         EXT4_INODE_COMPR        = 2,    /* Compress file */
 430         EXT4_INODE_SYNC         = 3,    /* Synchronous updates */
 431         EXT4_INODE_IMMUTABLE    = 4,    /* Immutable file */
 432         EXT4_INODE_APPEND       = 5,    /* writes to file may only append */
 433         EXT4_INODE_NODUMP       = 6,    /* do not dump file */
 434         EXT4_INODE_NOATIME      = 7,    /* do not update atime */
 435 /* Reserved for compression usage... */
 436         EXT4_INODE_DIRTY        = 8,
 437         EXT4_INODE_COMPRBLK     = 9,    /* One or more compressed clusters */
 438         EXT4_INODE_NOCOMPR      = 10,   /* Don't compress */
 439         EXT4_INODE_ECOMPR       = 11,   /* Compression error */
 440 /* End compression flags --- maybe not all used */
 441         EXT4_INODE_INDEX        = 12,   /* hash-indexed directory */
 442         EXT4_INODE_IMAGIC       = 13,   /* AFS directory */
 443         EXT4_INODE_JOURNAL_DATA = 14,   /* file data should be journaled */
 444         EXT4_INODE_NOTAIL       = 15,   /* file tail should not be merged */
 445         EXT4_INODE_DIRSYNC      = 16,   /* dirsync behaviour (directories only) */
 446         EXT4_INODE_TOPDIR       = 17,   /* Top of directory hierarchies*/
 447         EXT4_INODE_HUGE_FILE    = 18,   /* Set to each huge file */
 448         EXT4_INODE_EXTENTS      = 19,   /* Inode uses extents */
 449         EXT4_INODE_EA_INODE     = 21,   /* Inode used for large EA */
 450         EXT4_INODE_EOFBLOCKS    = 22,   /* Blocks allocated beyond EOF */
 451         EXT4_INODE_RESERVED     = 31,   /* reserved for ext4 lib */
 452 };
 453
 454 #define TEST_FLAG_VALUE(FLAG) (EXT4_##FLAG##_FL == (1 << EXT4_INODE_##FLAG))
 455 #define CHECK_FLAG_VALUE(FLAG) if (!TEST_FLAG_VALUE(FLAG)) { \
 456         printk(KERN_EMERG "EXT4 flag fail: " #FLAG ": %d %d\n", \
 457                 EXT4_##FLAG##_FL, EXT4_INODE_##FLAG); BUG_ON(1); }
 458
 459 /*
 460  * Since it's pretty easy to mix up bit numbers and hex values, and we
 461  * can't do a compile-time test for ENUM values, we use a run-time
 462  * test to make sure that EXT4_XXX_FL is consistent with respect to
 463  * EXT4_INODE_XXX.  If all is well the printk and BUG_ON will all drop
 464  * out so it won't cost any extra space in the compiled kernel image.
 465  * But it's important that these values are the same, since we are
 466  * using EXT4_INODE_XXX to test for the flag values, but EXT4_XX_FL
 467  * must be consistent with the values of FS_XXX_FL defined in
 468  * include/linux/fs.h and the on-disk values found in ext2, ext3, and
 469  * ext4 filesystems, and of course the values defined in e2fsprogs.
 470  *
 471  * It's not paranoia if the Murphy's Law really *is* out to get you.  :-)
 472  */
 473 static inline void ext4_check_flag_values(void)
 474 {
 475         CHECK_FLAG_VALUE(SECRM);
 476         CHECK_FLAG_VALUE(UNRM);
 477         CHECK_FLAG_VALUE(COMPR);
 478         CHECK_FLAG_VALUE(SYNC);
 479         CHECK_FLAG_VALUE(IMMUTABLE);
 480         CHECK_FLAG_VALUE(APPEND);
 481         CHECK_FLAG_VALUE(NODUMP);
 482         CHECK_FLAG_VALUE(NOATIME);
 483         CHECK_FLAG_VALUE(DIRTY);
 484         CHECK_FLAG_VALUE(COMPRBLK);
 485         CHECK_FLAG_VALUE(NOCOMPR);
 486         CHECK_FLAG_VALUE(ECOMPR);
 487         CHECK_FLAG_VALUE(INDEX);
 488         CHECK_FLAG_VALUE(IMAGIC);
 489         CHECK_FLAG_VALUE(JOURNAL_DATA);
 490         CHECK_FLAG_VALUE(NOTAIL);
 491         CHECK_FLAG_VALUE(DIRSYNC);
 492         CHECK_FLAG_VALUE(TOPDIR);
 493         CHECK_FLAG_VALUE(HUGE_FILE);
 494         CHECK_FLAG_VALUE(EXTENTS);
 495         CHECK_FLAG_VALUE(EA_INODE);
 496         CHECK_FLAG_VALUE(EOFBLOCKS);
 497         CHECK_FLAG_VALUE(RESERVED);
 498 }
 499
 500 /* Used to pass group descriptor data when online resize is done */
 501 struct ext4_new_group_input {
 502         __u32 group;            /* Group number for this data */
 503         __u64 block_bitmap;     /* Absolute block number of block bitmap */
 504         __u64 inode_bitmap;     /* Absolute block number of inode bitmap */
 505         __u64 inode_table;      /* Absolute block number of inode table start */
 506         __u32 blocks_count;     /* Total number of blocks in this group */
 507         __u16 reserved_blocks;  /* Number of reserved blocks in this group */
 508         __u16 unused;
 509 };
 510
 511 #if defined(__KERNEL__) && defined(CONFIG_COMPAT)
 512 struct compat_ext4_new_group_input {
 513         u32 group;
 514         compat_u64 block_bitmap;
 515         compat_u64 inode_bitmap;
 516         compat_u64 inode_table;
 517         u32 blocks_count;
 518         u16 reserved_blocks;
 519         u16 unused;
 520 };
 521 #endif
 522
 523 /* The struct ext4_new_group_input in kernel space, with free_blocks_count */
 524 struct ext4_new_group_data {
 525         __u32 group;
 526         __u64 block_bitmap;
 527         __u64 inode_bitmap;
 528         __u64 inode_table;
 529         __u32 blocks_count;
 530         __u16 reserved_blocks;
 531         __u16 unused;
 532         __u32 free_blocks_count;
 533 };
 534
 535 /* Indexes used to index group tables in ext4_new_group_data */
 536 enum {
 537         BLOCK_BITMAP = 0,       /* block bitmap */
 538         INODE_BITMAP,           /* inode bitmap */
 539         INODE_TABLE,            /* inode tables */
 540         GROUP_TABLE_COUNT,
 541 };
 542
 543 /*
 544  * Flags used by ext4_map_blocks()
 545  */
 546         /* Allocate any needed blocks and/or convert an unitialized
 547            extent to be an initialized ext4 */
 548 #define EXT4_GET_BLOCKS_CREATE                  0x0001
 549         /* Request the creation of an unitialized extent */
 550 #define EXT4_GET_BLOCKS_UNINIT_EXT              0x0002
 551 #define EXT4_GET_BLOCKS_CREATE_UNINIT_EXT       (EXT4_GET_BLOCKS_UNINIT_EXT|\
 552                                                  EXT4_GET_BLOCKS_CREATE)
 553         /* Caller is from the delayed allocation writeout path,
 554            so set the magic i_delalloc_reserve_flag after taking the
 555            inode allocation semaphore for */
 556 #define EXT4_GET_BLOCKS_DELALLOC_RESERVE        0x0004
 557         /* caller is from the direct IO path, request to creation of an
 558         unitialized extents if not allocated, split the uninitialized
 559         extent if blocks has been preallocated already*/
 560 #define EXT4_GET_BLOCKS_PRE_IO                  0x0008
 561 #define EXT4_GET_BLOCKS_CONVERT                 0x0010
 562 #define EXT4_GET_BLOCKS_IO_CREATE_EXT           (EXT4_GET_BLOCKS_PRE_IO|\
 563                                          EXT4_GET_BLOCKS_CREATE_UNINIT_EXT)
 564         /* Convert extent to initialized after IO complete */
 565 #define EXT4_GET_BLOCKS_IO_CONVERT_EXT          (EXT4_GET_BLOCKS_CONVERT|\
 566                                          EXT4_GET_BLOCKS_CREATE_UNINIT_EXT)
 567         /* Punch out blocks of an extent */
 568 #define EXT4_GET_BLOCKS_PUNCH_OUT_EXT           0x0020
 569         /* Don't normalize allocation size (used for fallocate) */
 570 #define EXT4_GET_BLOCKS_NO_NORMALIZE            0x0040
 571         /* Request will not result in inode size update (user for fallocate) */
 572 #define EXT4_GET_BLOCKS_KEEP_SIZE               0x0080
 573         /* Do not take i_data_sem locking in ext4_map_blocks */
 574 #define EXT4_GET_BLOCKS_NO_LOCK                 0x0100
 575
 576 /*
 577  * Flags used by ext4_free_blocks
 578  */
 579 #define EXT4_FREE_BLOCKS_METADATA       0x0001
 580 #define EXT4_FREE_BLOCKS_FORGET         0x0002
 581 #define EXT4_FREE_BLOCKS_VALIDATED      0x0004
 582 #define EXT4_FREE_BLOCKS_NO_QUOT_UPDATE 0x0008
 583 #define EXT4_FREE_BLOCKS_NOFREE_FIRST_CLUSTER   0x0010
 584 #define EXT4_FREE_BLOCKS_NOFREE_LAST_CLUSTER    0x0020
 585
 586 /*
 587  * Flags used by ext4_discard_partial_page_buffers
 588  */
 589 #define EXT4_DISCARD_PARTIAL_PG_ZERO_UNMAPPED   0x0001
 590
 591 /*
 592  * ioctl commands
 593  */
 594 #define EXT4_IOC_GETFLAGS               FS_IOC_GETFLAGS
 595 #define EXT4_IOC_SETFLAGS               FS_IOC_SETFLAGS
 596 #define EXT4_IOC_GETVERSION             _IOR('f', 3, long)
 597 #define EXT4_IOC_SETVERSION             _IOW('f', 4, long)
 598 #define EXT4_IOC_GETVERSION_OLD         FS_IOC_GETVERSION
 599 #define EXT4_IOC_SETVERSION_OLD         FS_IOC_SETVERSION
 600 #define EXT4_IOC_GETRSVSZ               _IOR('f', 5, long)
 601 #define EXT4_IOC_SETRSVSZ               _IOW('f', 6, long)
 602 #define EXT4_IOC_GROUP_EXTEND           _IOW('f', 7, unsigned long)
 603 #define EXT4_IOC_GROUP_ADD              _IOW('f', 8, struct ext4_new_group_input)
 604 #define EXT4_IOC_MIGRATE                _IO('f', 9)
 605  /* note ioctl 10 reserved for an early version of the FIEMAP ioctl */
 606  /* note ioctl 11 reserved for filesystem-independent FIEMAP ioctl */
 607 #define EXT4_IOC_ALLOC_DA_BLKS          _IO('f', 12)
 608 #define EXT4_IOC_MOVE_EXT               _IOWR('f', 15, struct move_extent)
 609 #define EXT4_IOC_RESIZE_FS              _IOW('f', 16, __u64)
 610
 611 #if defined(__KERNEL__) && defined(CONFIG_COMPAT)
 612 /*
 613  * ioctl commands in 32 bit emulation
 614  */
 615 #define EXT4_IOC32_GETFLAGS             FS_IOC32_GETFLAGS
 616 #define EXT4_IOC32_SETFLAGS             FS_IOC32_SETFLAGS
 617 #define EXT4_IOC32_GETVERSION           _IOR('f', 3, int)
 618 #define EXT4_IOC32_SETVERSION           _IOW('f', 4, int)
 619 #define EXT4_IOC32_GETRSVSZ             _IOR('f', 5, int)
 620 #define EXT4_IOC32_SETRSVSZ             _IOW('f', 6, int)
 621 #define EXT4_IOC32_GROUP_EXTEND         _IOW('f', 7, unsigned int)
 622 #define EXT4_IOC32_GROUP_ADD            _IOW('f', 8, struct compat_ext4_new_group_input)
 623 #define EXT4_IOC32_GETVERSION_OLD       FS_IOC32_GETVERSION
 624 #define EXT4_IOC32_SETVERSION_OLD       FS_IOC32_SETVERSION
 625 #endif
 626
 627 /* Max physical block we can address w/o extents */
 628 #define EXT4_MAX_BLOCK_FILE_PHYS        0xFFFFFFFF
 629
 630 /*
 631  * Structure of an inode on the disk
 632  */
 633 struct ext4_inode {
 634         __le16  i_mode;         /* File mode */
 635         __le16  i_uid;          /* Low 16 bits of Owner Uid */
 636         __le32  i_size_lo;      /* Size in bytes */
 637         __le32  i_atime;        /* Access time */
 638         __le32  i_ctime;        /* Inode Change time */
 639         __le32  i_mtime;        /* Modification time */
 640         __le32  i_dtime;        /* Deletion Time */
 641         __le16  i_gid;          /* Low 16 bits of Group Id */
 642         __le16  i_links_count;  /* Links count */
 643         __le32  i_blocks_lo;    /* Blocks count */
 644         __le32  i_flags;        /* File flags */
 645         union {
 646                 struct {
 647                         __le32  l_i_version;
 648                 } linux1;
 649                 struct {
 650                         __u32  h_i_translator;
 651                 } hurd1;
 652                 struct {
 653                         __u32  m_i_reserved1;
 654                 } masix1;
 655         } osd1;                         /* OS dependent 1 */
 656         __le32  i_block[EXT4_N_BLOCKS];/* Pointers to blocks */
 657         __le32  i_generation;   /* File version (for NFS) */
 658         __le32  i_file_acl_lo;  /* File ACL */
 659         __le32  i_size_high;
 660         __le32  i_obso_faddr;   /* Obsoleted fragment address */
 661         union {
 662                 struct {
 663                         __le16  l_i_blocks_high; /* were l_i_reserved1 */
 664                         __le16  l_i_file_acl_high;
 665                         __le16  l_i_uid_high;   /* these 2 fields */
 666                         __le16  l_i_gid_high;   /* were reserved2[0] */
 667                         __le16  l_i_checksum_lo;/* crc32c(uuid+inum+inode) LE */
 668                         __le16  l_i_reserved;
 669                 } linux2;
 670                 struct {
 671                         __le16  h_i_reserved1;  /* Obsoleted fragment number/size which are removed in ext4 */
 672                         __u16   h_i_mode_high;
 673                         __u16   h_i_uid_high;
 674                         __u16   h_i_gid_high;
 675                         __u32   h_i_author;
 676                 } hurd2;
 677                 struct {
 678                         __le16  h_i_reserved1;  /* Obsoleted fragment number/size which are removed in ext4 */
 679                         __le16  m_i_file_acl_high;
 680                         __u32   m_i_reserved2[2];
 681                 } masix2;
 682         } osd2;                         /* OS dependent 2 */
 683         __le16  i_extra_isize;
 684         __le16  i_checksum_hi;  /* crc32c(uuid+inum+inode) BE */
 685         __le32  i_ctime_extra;  /* extra Change time      (nsec << 2 | epoch) */
 686         __le32  i_mtime_extra;  /* extra Modification time(nsec << 2 | epoch) */
 687         __le32  i_atime_extra;  /* extra Access time      (nsec << 2 | epoch) */
 688         __le32  i_crtime;       /* File Creation time */
 689         __le32  i_crtime_extra; /* extra FileCreationtime (nsec << 2 | epoch) */
 690         __le32  i_version_hi;   /* high 32 bits for 64-bit version */
 691 };
 692
 693 struct move_extent {
 694         __u32 reserved;         /* should be zero */
 695         __u32 donor_fd;         /* donor file descriptor */
 696         __u64 orig_start;       /* logical start offset in block for orig */
 697         __u64 donor_start;      /* logical start offset in block for donor */
 698         __u64 len;              /* block length to be moved */
 699         __u64 moved_len;        /* moved block length */
 700 };
 701
 702 #define EXT4_EPOCH_BITS 2
 703 #define EXT4_EPOCH_MASK ((1 << EXT4_EPOCH_BITS) - 1)
 704 #define EXT4_NSEC_MASK  (~0UL << EXT4_EPOCH_BITS)
 705
 706 /*
 707  * Extended fields will fit into an inode if the filesystem was formatted
 708  * with large inodes (-I 256 or larger) and there are not currently any EAs
 709  * consuming all of the available space. For new inodes we always reserve
 710  * enough space for the kernel's known extended fields, but for inodes
 711  * created with an old kernel this might not have been the case. None of
 712  * the extended inode fields is critical for correct filesystem operation.
 713  * This macro checks if a certain field fits in the inode. Note that
 714  * inode-size = GOOD_OLD_INODE_SIZE + i_extra_isize
 715  */
 716 #define EXT4_FITS_IN_INODE(ext4_inode, einode, field)   \
 717         ((offsetof(typeof(*ext4_inode), field) +        \
 718           sizeof((ext4_inode)->field))                  \
 719         <= (EXT4_GOOD_OLD_INODE_SIZE +                  \
 720             (einode)->i_extra_isize))                   \
 721
 722 static inline __le32 ext4_encode_extra_time(struct timespec *time)
 723 {
 724        return cpu_to_le32((sizeof(time->tv_sec) > 4 ?
 725                            (time->tv_sec >> 32) & EXT4_EPOCH_MASK : 0) |
 726                           ((time->tv_nsec << EXT4_EPOCH_BITS) & EXT4_NSEC_MASK));
 727 }
 728
 729 static inline void ext4_decode_extra_time(struct timespec *time, __le32 extra)
 730 {
 731        if (sizeof(time->tv_sec) > 4)
 732                time->tv_sec |= (__u64)(le32_to_cpu(extra) & EXT4_EPOCH_MASK)
 733                                << 32;
 734        time->tv_nsec = (le32_to_cpu(extra) & EXT4_NSEC_MASK) >> EXT4_EPOCH_BITS;
 735 }
 736
 737 #define EXT4_INODE_SET_XTIME(xtime, inode, raw_inode)                          \
 738 do {                                                                           \
 739         (raw_inode)->xtime = cpu_to_le32((inode)->xtime.tv_sec);               \
 740         if (EXT4_FITS_IN_INODE(raw_inode, EXT4_I(inode), xtime ## _extra))     \
 741                 (raw_inode)->xtime ## _extra =                                 \
 742                                 ext4_encode_extra_time(&(inode)->xtime);       \
 743 } while (0)
 744
 745 #define EXT4_EINODE_SET_XTIME(xtime, einode, raw_inode)                        \
 746 do {                                                                           \
 747         if (EXT4_FITS_IN_INODE(raw_inode, einode, xtime))                      \
 748                 (raw_inode)->xtime = cpu_to_le32((einode)->xtime.tv_sec);      \
 749         if (EXT4_FITS_IN_INODE(raw_inode, einode, xtime ## _extra))            \
 750                 (raw_inode)->xtime ## _extra =                                 \
 751                                 ext4_encode_extra_time(&(einode)->xtime);      \
 752 } while (0)
 753
 754 #define EXT4_INODE_GET_XTIME(xtime, inode, raw_inode)                          \
 755 do {                                                                           \
 756         (inode)->xtime.tv_sec = (signed)le32_to_cpu((raw_inode)->xtime);       \
 757         if (EXT4_FITS_IN_INODE(raw_inode, EXT4_I(inode), xtime ## _extra))     \
 758                 ext4_decode_extra_time(&(inode)->xtime,                        \
 759                                        raw_inode->xtime ## _extra);            \
 760         else                                                                   \
 761                 (inode)->xtime.tv_nsec = 0;                                    \
 762 } while (0)
 763
 764 #define EXT4_EINODE_GET_XTIME(xtime, einode, raw_inode)                        \
 765 do {                                                                           \
 766         if (EXT4_FITS_IN_INODE(raw_inode, einode, xtime))                      \
 767                 (einode)->xtime.tv_sec =                                       \
 768                         (signed)le32_to_cpu((raw_inode)->xtime);               \
 769         if (EXT4_FITS_IN_INODE(raw_inode, einode, xtime ## _extra))            \
 770                 ext4_decode_extra_time(&(einode)->xtime,                       \
 771                                        raw_inode->xtime ## _extra);            \
 772         else                                                                   \
 773                 (einode)->xtime.tv_nsec = 0;                                   \
 774 } while (0)
 775
 776 #define i_disk_version osd1.linux1.l_i_version
 777
 778 #if defined(__KERNEL__) || defined(__linux__)
 779 #define i_reserved1     osd1.linux1.l_i_reserved1
 780 #define i_file_acl_high osd2.linux2.l_i_file_acl_high
 781 #define i_blocks_high   osd2.linux2.l_i_blocks_high
 782 #define i_uid_low       i_uid
 783 #define i_gid_low       i_gid
 784 #define i_uid_high      osd2.linux2.l_i_uid_high
 785 #define i_gid_high      osd2.linux2.l_i_gid_high
 786 #define i_checksum_lo   osd2.linux2.l_i_checksum_lo
 787
 788 #elif defined(__GNU__)
 789
 790 #define i_translator    osd1.hurd1.h_i_translator
 791 #define i_uid_high      osd2.hurd2.h_i_uid_high
 792 #define i_gid_high      osd2.hurd2.h_i_gid_high
 793 #define i_author        osd2.hurd2.h_i_author
 794
 795 #elif defined(__masix__)
 796
 797 #define i_reserved1     osd1.masix1.m_i_reserved1
 798 #define i_file_acl_high osd2.masix2.m_i_file_acl_high
 799 #define i_reserved2     osd2.masix2.m_i_reserved2
 800
 801 #endif /* defined(__KERNEL__) || defined(__linux__) */
 802
 803 /*
 804  * storage for cached extent
 805  * If ec_len == 0, then the cache is invalid.
 806  * If ec_start == 0, then the cache represents a gap (null mapping)
 807  */
 808 struct ext4_ext_cache {
 809         ext4_fsblk_t    ec_start;
 810         ext4_lblk_t     ec_block;
 811         __u32           ec_len; /* must be 32bit to return holes */
 812 };
 813
 814 #include "extents_status.h"
 815
 816 /*
 817  * fourth extended file system inode data in memory
 818  */
 819 struct ext4_inode_info {
 820         __le32  i_data[15];     /* unconverted */
 821         __u32   i_dtime;
 822         ext4_fsblk_t    i_file_acl;
 823
 824         /*
 825          * i_block_group is the number of the block group which contains
 826          * this file's inode.  Constant across the lifetime of the inode,
 827          * it is ued for making block allocation decisions - we try to
 828          * place a file's data blocks near its inode block, and new inodes
 829          * near to their parent directory's inode.
 830          */
 831         ext4_group_t    i_block_group;
 832         ext4_lblk_t     i_dir_start_lookup;
 833 #if (BITS_PER_LONG < 64)
 834         unsigned long   i_state_flags;          /* Dynamic state flags */
 835 #endif
 836         unsigned long   i_flags;
 837
 838 #ifdef CONFIG_EXT4_FS_XATTR
 839         /*
 840          * Extended attributes can be read independently of the main file
 841          * data. Taking i_mutex even when reading would cause contention
 842          * between readers of EAs and writers of regular file data, so
 843          * instead we synchronize on xattr_sem when reading or changing
 844          * EAs.
 845          */
 846         struct rw_semaphore xattr_sem;
 847 #endif
 848
 849         struct list_head i_orphan;      /* unlinked but open inodes */
 850
 851         /*
 852          * i_disksize keeps track of what the inode size is ON DISK, not
 853          * in memory.  During truncate, i_size is set to the new size by
 854          * the VFS prior to calling ext4_truncate(), but the filesystem won't
 855          * set i_disksize to 0 until the truncate is actually under way.
 856          *
 857          * The intent is that i_disksize always represents the blocks which
 858          * are used by this file.  This allows recovery to restart truncate
 859          * on orphans if we crash during truncate.  We actually write i_disksize
 860          * into the on-disk inode when writing inodes out, instead of i_size.
 861          *
 862          * The only time when i_disksize and i_size may be different is when
 863          * a truncate is in progress.  The only things which change i_disksize
 864          * are ext4_get_block (growth) and ext4_truncate (shrinkth).
 865          */
 866         loff_t  i_disksize;
 867
 868         /*
 869          * i_data_sem is for serialising ext4_truncate() against
 870          * ext4_getblock().  In the 2.4 ext2 design, great chunks of inode's
 871          * data tree are chopped off during truncate. We can't do that in
 872          * ext4 because whenever we perform intermediate commits during
 873          * truncate, the inode and all the metadata blocks *must* be in a
 874          * consistent state which allows truncation of the orphans to restart
 875          * during recovery.  Hence we must fix the get_block-vs-truncate race
 876          * by other means, so we have i_data_sem.
 877          */
 878         struct rw_semaphore i_data_sem;
 879         struct inode vfs_inode;
 880         struct jbd2_inode *jinode;
 881
 882         struct ext4_ext_cache i_cached_extent;
 883         /*
 884          * File creation time. Its function is same as that of
 885          * struct timespec i_{a,c,m}time in the generic inode.
 886          */
 887         struct timespec i_crtime;
 888
 889         /* mballoc */
 890         struct list_head i_prealloc_list;
 891         spinlock_t i_prealloc_lock;
 892
 893         /* extents status tree */
 894         struct ext4_es_tree i_es_tree;
 895         rwlock_t i_es_lock;
 896
 897         /* ialloc */
 898         ext4_group_t    i_last_alloc_group;
 899
 900         /* allocation reservation info for delalloc */
 901         /* In case of bigalloc, these refer to clusters rather than blocks */
 902         unsigned int i_reserved_data_blocks;
 903         unsigned int i_reserved_meta_blocks;
 904         unsigned int i_allocated_meta_blocks;
 905         ext4_lblk_t i_da_metadata_calc_last_lblock;
 906         int i_da_metadata_calc_len;
 907
 908         /* on-disk additional length */
 909         __u16 i_extra_isize;
 910
 911 #ifdef CONFIG_QUOTA
 912         /* quota space reservation, managed internally by quota code */
 913         qsize_t i_reserved_quota;
 914 #endif
 915
 916         /* completed IOs that might need unwritten extents handling */
 917         struct list_head i_completed_io_list;
 918         spinlock_t i_completed_io_lock;
 919         atomic_t i_ioend_count; /* Number of outstanding io_end structs */
 920         atomic_t i_unwritten; /* Nr. of inflight conversions pending */
 921
 922         spinlock_t i_block_reservation_lock;
 923
 924         /*
 925          * Transactions that contain inode's metadata needed to complete
 926          * fsync and fdatasync, respectively.
 927          */
 928         tid_t i_sync_tid;
 929         tid_t i_datasync_tid;
 930
 931         /* Precomputed uuid+inum+igen checksum for seeding inode checksums */
 932         __u32 i_csum_seed;
 933 };
 934
 935 /*
 936  * File system states
 937  */
 938 #define EXT4_VALID_FS                   0x0001  /* Unmounted cleanly */
 939 #define EXT4_ERROR_FS                   0x0002  /* Errors detected */
 940 #define EXT4_ORPHAN_FS                  0x0004  /* Orphans being recovered */
 941
 942 /*
 943  * Misc. filesystem flags
 944  */
 945 #define EXT2_FLAGS_SIGNED_HASH          0x0001  /* Signed dirhash in use */
 946 #define EXT2_FLAGS_UNSIGNED_HASH        0x0002  /* Unsigned dirhash in use */
 947 #define EXT2_FLAGS_TEST_FILESYS         0x0004  /* to test development code */
 948
 949 /*
 950  * Mount flags
 951  */
 952 #define EXT4_MOUNT_GRPID                0x00004 /* Create files with directory's group */
 953 #define EXT4_MOUNT_DEBUG                0x00008 /* Some debugging messages */
 954 #define EXT4_MOUNT_ERRORS_CONT          0x00010 /* Continue on errors */
 955 #define EXT4_MOUNT_ERRORS_RO            0x00020 /* Remount fs ro on errors */
 956 #define EXT4_MOUNT_ERRORS_PANIC         0x00040 /* Panic on errors */
 957 #define EXT4_MOUNT_ERRORS_MASK          0x00070
 958 #define EXT4_MOUNT_MINIX_DF             0x00080 /* Mimics the Minix statfs */
 959 #define EXT4_MOUNT_NOLOAD               0x00100 /* Don't use existing journal*/
 960 #define EXT4_MOUNT_DATA_FLAGS           0x00C00 /* Mode for data writes: */
 961 #define EXT4_MOUNT_JOURNAL_DATA         0x00400 /* Write data to journal */
 962 #define EXT4_MOUNT_ORDERED_DATA         0x00800 /* Flush data before commit */
 963 #define EXT4_MOUNT_WRITEBACK_DATA       0x00C00 /* No data ordering */
 964 #define EXT4_MOUNT_UPDATE_JOURNAL       0x01000 /* Update the journal format */
 965 #define EXT4_MOUNT_NO_UID32             0x02000  /* Disable 32-bit UIDs */
 966 #define EXT4_MOUNT_XATTR_USER           0x04000 /* Extended user attributes */
 967 #define EXT4_MOUNT_POSIX_ACL            0x08000 /* POSIX Access Control Lists */
 968 #define EXT4_MOUNT_NO_AUTO_DA_ALLOC     0x10000 /* No auto delalloc mapping */
 969 #define EXT4_MOUNT_BARRIER              0x20000 /* Use block barriers */
 970 #define EXT4_MOUNT_QUOTA                0x80000 /* Some quota option set */
 971 #define EXT4_MOUNT_USRQUOTA             0x100000 /* "old" user quota */
 972 #define EXT4_MOUNT_GRPQUOTA             0x200000 /* "old" group quota */
 973 #define EXT4_MOUNT_DIOREAD_NOLOCK       0x400000 /* Enable support for dio read nolocking */
 974 #define EXT4_MOUNT_JOURNAL_CHECKSUM     0x800000 /* Journal checksums */
 975 #define EXT4_MOUNT_JOURNAL_ASYNC_COMMIT 0x1000000 /* Journal Async Commit */
 976 #define EXT4_MOUNT_MBLK_IO_SUBMIT       0x4000000 /* multi-block io submits */
 977 #define EXT4_MOUNT_DELALLOC             0x8000000 /* Delalloc support */
 978 #define EXT4_MOUNT_DATA_ERR_ABORT       0x10000000 /* Abort on file data write */
 979 #define EXT4_MOUNT_BLOCK_VALIDITY       0x20000000 /* Block validity checking */
 980 #define EXT4_MOUNT_DISCARD              0x40000000 /* Issue DISCARD requests */
 981 #define EXT4_MOUNT_INIT_INODE_TABLE     0x80000000 /* Initialize uninitialized itables */
 982
 983 #define EXT4_MOUNT2_EXPLICIT_DELALLOC   0x00000001 /* User explicitly
 984                                                       specified delalloc */
 985
 986 #define clear_opt(sb, opt)              EXT4_SB(sb)->s_mount_opt &= \
 987                                                 ~EXT4_MOUNT_##opt
 988 #define set_opt(sb, opt)                EXT4_SB(sb)->s_mount_opt |= \
 989                                                 EXT4_MOUNT_##opt
 990 #define test_opt(sb, opt)               (EXT4_SB(sb)->s_mount_opt & \
 991                                          EXT4_MOUNT_##opt)
 992
 993 #define clear_opt2(sb, opt)             EXT4_SB(sb)->s_mount_opt2 &= \
 994                                                 ~EXT4_MOUNT2_##opt
 995 #define set_opt2(sb, opt)               EXT4_SB(sb)->s_mount_opt2 |= \
 996                                                 EXT4_MOUNT2_##opt
 997 #define test_opt2(sb, opt)              (EXT4_SB(sb)->s_mount_opt2 & \
 998                                          EXT4_MOUNT2_##opt)
 999
1000 #define ext4_test_and_set_bit           __test_and_set_bit_le
1001 #define ext4_set_bit                    __set_bit_le
1002 #define ext4_set_bit_atomic             ext2_set_bit_atomic
1003 #define ext4_test_and_clear_bit         __test_and_clear_bit_le
1004 #define ext4_clear_bit                  __clear_bit_le
1005 #define ext4_clear_bit_atomic           ext2_clear_bit_atomic
1006 #define ext4_test_bit                   test_bit_le
1007 #define ext4_find_next_zero_bit         find_next_zero_bit_le
1008 #define ext4_find_next_bit              find_next_bit_le
1009
1010 extern void ext4_set_bits(void *bm, int cur, int len);
1011
1012 /*
1013  * Maximal mount counts between two filesystem checks
1014  */
1015 #define EXT4_DFL_MAX_MNT_COUNT          20      /* Allow 20 mounts */
1016 #define EXT4_DFL_CHECKINTERVAL          0       /* Don't use interval check */
1017
1018 /*
1019  * Behaviour when detecting errors
1020  */
1021 #define EXT4_ERRORS_CONTINUE            1       /* Continue execution */
1022 #define EXT4_ERRORS_RO                  2       /* Remount fs read-only */
1023 #define EXT4_ERRORS_PANIC               3       /* Panic */
1024 #define EXT4_ERRORS_DEFAULT             EXT4_ERRORS_CONTINUE
1025
1026 /* Metadata checksum algorithm codes */
1027 #define EXT4_CRC32C_CHKSUM              1
1028
1029 /*
1030  * Structure of the super block
1031  */
1032 struct ext4_super_block {
1033 /*00*/  __le32  s_inodes_count;         /* Inodes count */
1034         __le32  s_blocks_count_lo;      /* Blocks count */
1035         __le32  s_r_blocks_count_lo;    /* Reserved blocks count */
1036         __le32  s_free_blocks_count_lo; /* Free blocks count */
1037 /*10*/  __le32  s_free_inodes_count;    /* Free inodes count */
1038         __le32  s_first_data_block;     /* First Data Block */
1039         __le32  s_log_block_size;       /* Block size */
1040         __le32  s_log_cluster_size;     /* Allocation cluster size */
1041 /*20*/  __le32  s_blocks_per_group;     /* # Blocks per group */
1042         __le32  s_clusters_per_group;   /* # Clusters per group */
1043         __le32  s_inodes_per_group;     /* # Inodes per group */
1044         __le32  s_mtime;                /* Mount time */
1045 /*30*/  __le32  s_wtime;                /* Write time */
1046         __le16  s_mnt_count;            /* Mount count */
1047         __le16  s_max_mnt_count;        /* Maximal mount count */
1048         __le16  s_magic;                /* Magic signature */
1049         __le16  s_state;                /* File system state */
1050         __le16  s_errors;               /* Behaviour when detecting errors */
1051         __le16  s_minor_rev_level;      /* minor revision level */
1052 /*40*/  __le32  s_lastcheck;            /* time of last check */
1053         __le32  s_checkinterval;        /* max. time between checks */
1054         __le32  s_creator_os;           /* OS */
1055         __le32  s_rev_level;            /* Revision level */
1056 /*50*/  __le16  s_def_resuid;           /* Default uid for reserved blocks */
1057         __le16  s_def_resgid;           /* Default gid for reserved blocks */
1058         /*
1059          * These fields are for EXT4_DYNAMIC_REV superblocks only.
1060          *
1061          * Note: the difference between the compatible feature set and
1062          * the incompatible feature set is that if there is a bit set
1063          * in the incompatible feature set that the kernel doesn't
1064          * know about, it should refuse to mount the filesystem.
1065          *
1066          * e2fsck's requirements are more strict; if it doesn't know
1067          * about a feature in either the compatible or incompatible
1068          * feature set, it must abort and not try to meddle with
1069          * things it doesn't understand...
1070          */
1071         __le32  s_first_ino;            /* First non-reserved inode */
1072         __le16  s_inode_size;           /* size of inode structure */
1073         __le16  s_block_group_nr;       /* block group # of this superblock */
1074         __le32  s_feature_compat;       /* compatible feature set */
1075 /*60*/  __le32  s_feature_incompat;     /* incompatible feature set */
1076         __le32  s_feature_ro_compat;    /* readonly-compatible feature set */
1077 /*68*/  __u8    s_uuid[16];             /* 128-bit uuid for volume */
1078 /*78*/  char    s_volume_name[16];      /* volume name */
1079 /*88*/  char    s_last_mounted[64];     /* directory where last mounted */
1080 /*C8*/  __le32  s_algorithm_usage_bitmap; /* For compression */
1081         /*
1082          * Performance hints.  Directory preallocation should only
1083          * happen if the EXT4_FEATURE_COMPAT_DIR_PREALLOC flag is on.
1084          */
1085         __u8    s_prealloc_blocks;      /* Nr of blocks to try to preallocate*/
1086         __u8    s_prealloc_dir_blocks;  /* Nr to preallocate for dirs */
1087         __le16  s_reserved_gdt_blocks;  /* Per group desc for online growth */
1088         /*
1089          * Journaling support valid if EXT4_FEATURE_COMPAT_HAS_JOURNAL set.
1090          */
1091 /*D0*/  __u8    s_journal_uuid[16];     /* uuid of journal superblock */
1092 /*E0*/  __le32  s_journal_inum;         /* inode number of journal file */
1093         __le32  s_journal_dev;          /* device number of journal file */
1094         __le32  s_last_orphan;          /* start of list of inodes to delete */
1095         __le32  s_hash_seed[4];         /* HTREE hash seed */
1096         __u8    s_def_hash_version;     /* Default hash version to use */
1097         __u8    s_jnl_backup_type;
1098         __le16  s_desc_size;            /* size of group descriptor */
1099 /*100*/ __le32  s_default_mount_opts;
1100         __le32  s_first_meta_bg;        /* First metablock block group */
1101         __le32  s_mkfs_time;            /* When the filesystem was created */
1102         __le32  s_jnl_blocks[17];       /* Backup of the journal inode */
1103         /* 64bit support valid if EXT4_FEATURE_COMPAT_64BIT */
1104 /*150*/ __le32  s_blocks_count_hi;      /* Blocks count */
1105         __le32  s_r_blocks_count_hi;    /* Reserved blocks count */
1106         __le32  s_free_blocks_count_hi; /* Free blocks count */
1107         __le16  s_min_extra_isize;      /* All inodes have at least # bytes */
1108         __le16  s_want_extra_isize;     /* New inodes should reserve # bytes */
1109         __le32  s_flags;                /* Miscellaneous flags */
1110         __le16  s_raid_stride;          /* RAID stride */
1111         __le16  s_mmp_update_interval;  /* # seconds to wait in MMP checking */
1112         __le64  s_mmp_block;            /* Block for multi-mount protection */
1113         __le32  s_raid_stripe_width;    /* blocks on all data disks (N*stride)*/
1114         __u8    s_log_groups_per_flex;  /* FLEX_BG group size */
1115         __u8    s_checksum_type;        /* metadata checksum algorithm used */
1116         __le16  s_reserved_pad;
1117         __le64  s_kbytes_written;       /* nr of lifetime kilobytes written */
1118         __le32  s_snapshot_inum;        /* Inode number of active snapshot */
1119         __le32  s_snapshot_id;          /* sequential ID of active snapshot */
1120         __le64  s_snapshot_r_blocks_count; /* reserved blocks for active
1121                                               snapshot's future use */
1122         __le32  s_snapshot_list;        /* inode number of the head of the
1123                                            on-disk snapshot list */
1124 #define EXT4_S_ERR_START offsetof(struct ext4_super_block, s_error_count)
1125         __le32  s_error_count;          /* number of fs errors */
1126         __le32  s_first_error_time;     /* first time an error happened */
1127         __le32  s_first_error_ino;      /* inode involved in first error */
1128         __le64  s_first_error_block;    /* block involved of first error */
1129         __u8    s_first_error_func[32]; /* function where the error happened */
1130         __le32  s_first_error_line;     /* line number where error happened */
1131         __le32  s_last_error_time;      /* most recent time of an error */
1132         __le32  s_last_error_ino;       /* inode involved in last error */
1133         __le32  s_last_error_line;      /* line number where error happened */
1134         __le64  s_last_error_block;     /* block involved of last error */
1135         __u8    s_last_error_func[32];  /* function where the error happened */
1136 #define EXT4_S_ERR_END offsetof(struct ext4_super_block, s_mount_opts)
1137         __u8    s_mount_opts[64];
1138         __le32  s_usr_quota_inum;       /* inode for tracking user quota */
1139         __le32  s_grp_quota_inum;       /* inode for tracking group quota */
1140         __le32  s_overhead_clusters;    /* overhead blocks/clusters in fs */
1141         __le32  s_reserved[108];        /* Padding to the end of the block */
1142         __le32  s_checksum;             /* crc32c(superblock) */
1143 };
1144
1145 #define EXT4_S_ERR_LEN (EXT4_S_ERR_END - EXT4_S_ERR_START)
1146
1147 #ifdef __KERNEL__
1148
1149 /*
1150  * run-time mount flags
1151  */
1152 #define EXT4_MF_MNTDIR_SAMPLED  0x0001
1153 #define EXT4_MF_FS_ABORTED      0x0002  /* Fatal error detected */
1154
1155 /*
1156  * fourth extended-fs super-block data in memory
1157  */
1158 struct ext4_sb_info {
1159         unsigned long s_desc_size;      /* Size of a group descriptor in bytes */
1160         unsigned long s_inodes_per_block;/* Number of inodes per block */
1161         unsigned long s_blocks_per_group;/* Number of blocks in a group */
1162         unsigned long s_clusters_per_group; /* Number of clusters in a group */
1163         unsigned long s_inodes_per_group;/* Number of inodes in a group */
1164         unsigned long s_itb_per_group;  /* Number of inode table blocks per group */
1165         unsigned long s_gdb_count;      /* Number of group descriptor blocks */
1166         unsigned long s_desc_per_block; /* Number of group descriptors per block */
1167         ext4_group_t s_groups_count;    /* Number of groups in the fs */
1168         ext4_group_t s_blockfile_groups;/* Groups acceptable for non-extent files */
1169         unsigned long s_overhead;  /* # of fs overhead clusters */
1170         unsigned int s_cluster_ratio;   /* Number of blocks per cluster */
1171         unsigned int s_cluster_bits;    /* log2 of s_cluster_ratio */
1172         loff_t s_bitmap_maxbytes;       /* max bytes for bitmap files */
1173         struct buffer_head * s_sbh;     /* Buffer containing the super block */
1174         struct ext4_super_block *s_es;  /* Pointer to the super block in the buffer */
1175         struct buffer_head **s_group_desc;
1176         unsigned int s_mount_opt;
1177         unsigned int s_mount_opt2;
1178         unsigned int s_mount_flags;
1179         unsigned int s_def_mount_opt;
1180         ext4_fsblk_t s_sb_block;
1181         kuid_t s_resuid;
1182         kgid_t s_resgid;
1183         unsigned short s_mount_state;
1184         unsigned short s_pad;
1185         int s_addr_per_block_bits;
1186         int s_desc_per_block_bits;
1187         int s_inode_size;
1188         int s_first_ino;
1189         unsigned int s_inode_readahead_blks;
1190         unsigned int s_inode_goal;
1191         spinlock_t s_next_gen_lock;
1192         u32 s_next_generation;
1193         u32 s_hash_seed[4];
1194         int s_def_hash_version;
1195         int s_hash_unsigned;    /* 3 if hash should be signed, 0 if not */
1196         struct percpu_counter s_freeclusters_counter;
1197         struct percpu_counter s_freeinodes_counter;
1198         struct percpu_counter s_dirs_counter;
1199         struct percpu_counter s_dirtyclusters_counter;
1200         struct blockgroup_lock *s_blockgroup_lock;
1201         struct proc_dir_entry *s_proc;
1202         struct kobject s_kobj;
1203         struct completion s_kobj_unregister;
1204         struct super_block *s_sb;
1205
1206         /* Journaling */
1207         struct journal_s *s_journal;
1208         struct list_head s_orphan;
1209         struct mutex s_orphan_lock;
1210         unsigned long s_resize_flags;           /* Flags indicating if there
1211                                                    is a resizer */
1212         unsigned long s_commit_interval;
1213         u32 s_max_batch_time;
1214         u32 s_min_batch_time;
1215         struct block_device *journal_bdev;
1216 #ifdef CONFIG_QUOTA
1217         char *s_qf_names[MAXQUOTAS];            /* Names of quota files with journalled quota */
1218         int s_jquota_fmt;                       /* Format of quota to use */
1219 #endif
1220         unsigned int s_want_extra_isize; /* New inodes should reserve # bytes */
1221         struct rb_root system_blks;
1222
1223 #ifdef EXTENTS_STATS
1224         /* ext4 extents stats */
1225         unsigned long s_ext_min;
1226         unsigned long s_ext_max;
1227         unsigned long s_depth_max;
1228         spinlock_t s_ext_stats_lock;
1229         unsigned long s_ext_blocks;
1230         unsigned long s_ext_extents;
1231 #endif
1232
1233         /* for buddy allocator */
1234         struct ext4_group_info ***s_group_info;
1235         struct inode *s_buddy_cache;
1236         spinlock_t s_md_lock;
1237         unsigned short *s_mb_offsets;
1238         unsigned int *s_mb_maxs;
1239         unsigned int s_group_info_size;
1240
1241         /* tunables */
1242         unsigned long s_stripe;
1243         unsigned int s_mb_stream_request;
1244         unsigned int s_mb_max_to_scan;
1245         unsigned int s_mb_min_to_scan;
1246         unsigned int s_mb_stats;
1247         unsigned int s_mb_order2_reqs;
1248         unsigned int s_mb_group_prealloc;
1249         unsigned int s_max_writeback_mb_bump;
1250         unsigned int s_max_dir_size_kb;
1251         /* where last allocation was done - for stream allocation */
1252         unsigned long s_mb_last_group;
1253         unsigned long s_mb_last_start;
1254
1255         /* stats for buddy allocator */
1256         atomic_t s_bal_reqs;    /* number of reqs with len > 1 */
1257         atomic_t s_bal_success; /* we found long enough chunks */
1258         atomic_t s_bal_allocated;       /* in blocks */
1259         atomic_t s_bal_ex_scanned;      /* total extents scanned */
1260         atomic_t s_bal_goals;   /* goal hits */
1261         atomic_t s_bal_breaks;  /* too long searches */
1262         atomic_t s_bal_2orders; /* 2^order hits */
1263         spinlock_t s_bal_lock;
1264         unsigned long s_mb_buddies_generated;
1265         unsigned long long s_mb_generation_time;
1266         atomic_t s_mb_lost_chunks;
1267         atomic_t s_mb_preallocated;
1268         atomic_t s_mb_discarded;
1269         atomic_t s_lock_busy;
1270
1271         /* locality groups */
1272         struct ext4_locality_group __percpu *s_locality_groups;
1273
1274         /* for write statistics */
1275         unsigned long s_sectors_written_start;
1276         u64 s_kbytes_written;
1277
1278         /* the size of zero-out chunk */
1279         unsigned int s_extent_max_zeroout_kb;
1280
1281         unsigned int s_log_groups_per_flex;
1282         struct flex_groups *s_flex_groups;
1283         ext4_group_t s_flex_groups_allocated;
1284
1285         /* workqueue for dio unwritten */
1286         struct workqueue_struct *dio_unwritten_wq;
1287
1288         /* timer for periodic error stats printing */
1289         struct timer_list s_err_report;
1290
1291         /* Lazy inode table initialization info */
1292         struct ext4_li_request *s_li_request;
1293         /* Wait multiplier for lazy initialization thread */
1294         unsigned int s_li_wait_mult;
1295
1296         /* Kernel thread for multiple mount protection */
1297         struct task_struct *s_mmp_tsk;
1298
1299         /* record the last minlen when FITRIM is called. */
1300         atomic_t s_last_trim_minblks;
1301
1302         /* Reference to checksum algorithm driver via cryptoapi */
1303         struct crypto_shash *s_chksum_driver;
1304
1305         /* Precomputed FS UUID checksum for seeding other checksums */
1306         __u32 s_csum_seed;
1307 };
1308
1309 static inline struct ext4_sb_info *EXT4_SB(struct super_block *sb)
1310 {
1311         return sb->s_fs_info;
1312 }
1313 static inline struct ext4_inode_info *EXT4_I(struct inode *inode)
1314 {
1315         return container_of(inode, struct ext4_inode_info, vfs_inode);
1316 }
1317
1318 static inline struct timespec ext4_current_time(struct inode *inode)
1319 {
1320         return (inode->i_sb->s_time_gran < NSEC_PER_SEC) ?
1321                 current_fs_time(inode->i_sb) : CURRENT_TIME_SEC;
1322 }
1323
1324 static inline int ext4_valid_inum(struct super_block *sb, unsigned long ino)
1325 {
1326         return ino == EXT4_ROOT_INO ||
1327                 ino == EXT4_USR_QUOTA_INO ||
1328                 ino == EXT4_GRP_QUOTA_INO ||
1329                 ino == EXT4_JOURNAL_INO ||
1330                 ino == EXT4_RESIZE_INO ||
1331                 (ino >= EXT4_FIRST_INO(sb) &&
1332                  ino <= le32_to_cpu(EXT4_SB(sb)->s_es->s_inodes_count));
1333 }
1334
1335 static inline void ext4_set_io_unwritten_flag(struct inode *inode,
1336                                               struct ext4_io_end *io_end)
1337 {
1338         if (!(io_end->flag & EXT4_IO_END_UNWRITTEN)) {
1339                 io_end->flag |= EXT4_IO_END_UNWRITTEN;
1340                 atomic_inc(&EXT4_I(inode)->i_unwritten);
1341         }
1342 }
1343
1344 static inline ext4_io_end_t *ext4_inode_aio(struct inode *inode)
1345 {
1346         return inode->i_private;
1347 }
1348
1349 static inline void ext4_inode_aio_set(struct inode *inode, ext4_io_end_t *io)
1350 {
1351         inode->i_private = io;
1352 }
1353
1354 /*
1355  * Inode dynamic state flags
1356  */
1357 enum {
1358         EXT4_STATE_JDATA,               /* journaled data exists */
1359         EXT4_STATE_NEW,                 /* inode is newly created */
1360         EXT4_STATE_XATTR,               /* has in-inode xattrs */
1361         EXT4_STATE_NO_EXPAND,           /* No space for expansion */
1362         EXT4_STATE_DA_ALLOC_CLOSE,      /* Alloc DA blks on close */
1363         EXT4_STATE_EXT_MIGRATE,         /* Inode is migrating */
1364         EXT4_STATE_DIO_UNWRITTEN,       /* need convert on dio done*/
1365         EXT4_STATE_NEWENTRY,            /* File just added to dir */
1366         EXT4_STATE_DELALLOC_RESERVED,   /* blks already reserved for delalloc */
1367         EXT4_STATE_DIOREAD_LOCK,        /* Disable support for dio read
1368                                            nolocking */
1369 };
1370
1371 #define EXT4_INODE_BIT_FNS(name, field, offset)                         \
1372 static inline int ext4_test_inode_##name(struct inode *inode, int bit)  \
1373 {                                                                       \
1374         return test_bit(bit + (offset), &EXT4_I(inode)->i_##field);     \
1375 }                                                                       \
1376 static inline void ext4_set_inode_##name(struct inode *inode, int bit)  \
1377 {                                                                       \
1378         set_bit(bit + (offset), &EXT4_I(inode)->i_##field);             \
1379 }                                                                       \
1380 static inline void ext4_clear_inode_##name(struct inode *inode, int bit) \
1381 {                                                                       \
1382         clear_bit(bit + (offset), &EXT4_I(inode)->i_##field);           \
1383 }
1384
1385 EXT4_INODE_BIT_FNS(flag, flags, 0)
1386 #if (BITS_PER_LONG < 64)
1387 EXT4_INODE_BIT_FNS(state, state_flags, 0)
1388
1389 static inline void ext4_clear_state_flags(struct ext4_inode_info *ei)
1390 {
1391         (ei)->i_state_flags = 0;
1392 }
1393 #else
1394 EXT4_INODE_BIT_FNS(state, flags, 32)
1395
1396 static inline void ext4_clear_state_flags(struct ext4_inode_info *ei)
1397 {
1398         /* We depend on the fact that callers will set i_flags */
1399 }
1400 #endif
1401 #else
1402 /* Assume that user mode programs are passing in an ext4fs superblock, not
1403  * a kernel struct super_block.  This will allow us to call the feature-test
1404  * macros from user land. */
1405 #define EXT4_SB(sb)     (sb)
1406 #endif
1407
1408 #define NEXT_ORPHAN(inode) EXT4_I(inode)->i_dtime
1409
1410 /*
1411  * Codes for operating systems
1412  */
1413 #define EXT4_OS_LINUX           0
1414 #define EXT4_OS_HURD            1
1415 #define EXT4_OS_MASIX           2
1416 #define EXT4_OS_FREEBSD         3
1417 #define EXT4_OS_LITES           4
1418
1419 /*
1420  * Revision levels
1421  */
1422 #define EXT4_GOOD_OLD_REV       0       /* The good old (original) format */
1423 #define EXT4_DYNAMIC_REV        1       /* V2 format w/ dynamic inode sizes */
1424
1425 #define EXT4_CURRENT_REV        EXT4_GOOD_OLD_REV
1426 #define EXT4_MAX_SUPP_REV       EXT4_DYNAMIC_REV
1427
1428 #define EXT4_GOOD_OLD_INODE_SIZE 128
1429
1430 /*
1431  * Feature set definitions
1432  */
1433
1434 #define EXT4_HAS_COMPAT_FEATURE(sb,mask)                        \
1435         ((EXT4_SB(sb)->s_es->s_feature_compat & cpu_to_le32(mask)) != 0)
1436 #define EXT4_HAS_RO_COMPAT_FEATURE(sb,mask)                     \
1437         ((EXT4_SB(sb)->s_es->s_feature_ro_compat & cpu_to_le32(mask)) != 0)
1438 #define EXT4_HAS_INCOMPAT_FEATURE(sb,mask)                      \
1439         ((EXT4_SB(sb)->s_es->s_feature_incompat & cpu_to_le32(mask)) != 0)
1440 #define EXT4_SET_COMPAT_FEATURE(sb,mask)                        \
1441         EXT4_SB(sb)->s_es->s_feature_compat |= cpu_to_le32(mask)
1442 #define EXT4_SET_RO_COMPAT_FEATURE(sb,mask)                     \
1443         EXT4_SB(sb)->s_es->s_feature_ro_compat |= cpu_to_le32(mask)
1444 #define EXT4_SET_INCOMPAT_FEATURE(sb,mask)                      \
1445         EXT4_SB(sb)->s_es->s_feature_incompat |= cpu_to_le32(mask)
1446 #define EXT4_CLEAR_COMPAT_FEATURE(sb,mask)                      \
1447         EXT4_SB(sb)->s_es->s_feature_compat &= ~cpu_to_le32(mask)
1448 #define EXT4_CLEAR_RO_COMPAT_FEATURE(sb,mask)                   \
1449         EXT4_SB(sb)->s_es->s_feature_ro_compat &= ~cpu_to_le32(mask)
1450 #define EXT4_CLEAR_INCOMPAT_FEATURE(sb,mask)                    \
1451         EXT4_SB(sb)->s_es->s_feature_incompat &= ~cpu_to_le32(mask)
1452
1453 #define EXT4_FEATURE_COMPAT_DIR_PREALLOC        0x0001
1454 #define EXT4_FEATURE_COMPAT_IMAGIC_INODES       0x0002
1455 #define EXT4_FEATURE_COMPAT_HAS_JOURNAL         0x0004
1456 #define EXT4_FEATURE_COMPAT_EXT_ATTR            0x0008
1457 #define EXT4_FEATURE_COMPAT_RESIZE_INODE        0x0010
1458 #define EXT4_FEATURE_COMPAT_DIR_INDEX           0x0020
1459
1460 #define EXT4_FEATURE_RO_COMPAT_SPARSE_SUPER     0x0001
1461 #define EXT4_FEATURE_RO_COMPAT_LARGE_FILE       0x0002
1462 #define EXT4_FEATURE_RO_COMPAT_BTREE_DIR        0x0004
1463 #define EXT4_FEATURE_RO_COMPAT_HUGE_FILE        0x0008
1464 #define EXT4_FEATURE_RO_COMPAT_GDT_CSUM         0x0010
1465 #define EXT4_FEATURE_RO_COMPAT_DIR_NLINK        0x0020
1466 #define EXT4_FEATURE_RO_COMPAT_EXTRA_ISIZE      0x0040
1467 #define EXT4_FEATURE_RO_COMPAT_QUOTA            0x0100
1468 #define EXT4_FEATURE_RO_COMPAT_BIGALLOC         0x0200
1469 /*
1470  * METADATA_CSUM also enables group descriptor checksums (GDT_CSUM).  When
1471  * METADATA_CSUM is set, group descriptor checksums use the same algorithm as
1472  * all other data structures' checksums.  However, the METADATA_CSUM and
1473  * GDT_CSUM bits are mutually exclusive.
1474  */
1475 #define EXT4_FEATURE_RO_COMPAT_METADATA_CSUM    0x0400
1476
1477 #define EXT4_FEATURE_INCOMPAT_COMPRESSION       0x0001
1478 #define EXT4_FEATURE_INCOMPAT_FILETYPE          0x0002
1479 #define EXT4_FEATURE_INCOMPAT_RECOVER           0x0004 /* Needs recovery */
1480 #define EXT4_FEATURE_INCOMPAT_JOURNAL_DEV       0x0008 /* Journal device */
1481 #define EXT4_FEATURE_INCOMPAT_META_BG           0x0010
1482 #define EXT4_FEATURE_INCOMPAT_EXTENTS           0x0040 /* extents support */
1483 #define EXT4_FEATURE_INCOMPAT_64BIT             0x0080
1484 #define EXT4_FEATURE_INCOMPAT_MMP               0x0100
1485 #define EXT4_FEATURE_INCOMPAT_FLEX_BG           0x0200
1486 #define EXT4_FEATURE_INCOMPAT_EA_INODE          0x0400 /* EA in inode */
1487 #define EXT4_FEATURE_INCOMPAT_DIRDATA           0x1000 /* data in dirent */
1488 #define EXT4_FEATURE_INCOMPAT_BG_USE_META_CSUM  0x2000 /* use crc32c for bg */
1489 #define EXT4_FEATURE_INCOMPAT_LARGEDIR          0x4000 /* >2GB or 3-lvl htree */
1490 #define EXT4_FEATURE_INCOMPAT_INLINEDATA        0x8000 /* data in inode */
1491
1492 #define EXT2_FEATURE_COMPAT_SUPP        EXT4_FEATURE_COMPAT_EXT_ATTR
1493 #define EXT2_FEATURE_INCOMPAT_SUPP      (EXT4_FEATURE_INCOMPAT_FILETYPE| \
1494                                          EXT4_FEATURE_INCOMPAT_META_BG)
1495 #define EXT2_FEATURE_RO_COMPAT_SUPP     (EXT4_FEATURE_RO_COMPAT_SPARSE_SUPER| \
1496                                          EXT4_FEATURE_RO_COMPAT_LARGE_FILE| \
1497                                          EXT4_FEATURE_RO_COMPAT_BTREE_DIR)
1498
1499 #define EXT3_FEATURE_COMPAT_SUPP        EXT4_FEATURE_COMPAT_EXT_ATTR
1500 #define EXT3_FEATURE_INCOMPAT_SUPP      (EXT4_FEATURE_INCOMPAT_FILETYPE| \
1501                                          EXT4_FEATURE_INCOMPAT_RECOVER| \
1502                                          EXT4_FEATURE_INCOMPAT_META_BG)
1503 #define EXT3_FEATURE_RO_COMPAT_SUPP     (EXT4_FEATURE_RO_COMPAT_SPARSE_SUPER| \
1504                                          EXT4_FEATURE_RO_COMPAT_LARGE_FILE| \
1505                                          EXT4_FEATURE_RO_COMPAT_BTREE_DIR)
1506
1507 #define EXT4_FEATURE_COMPAT_SUPP        EXT2_FEATURE_COMPAT_EXT_ATTR
1508 #define EXT4_FEATURE_INCOMPAT_SUPP      (EXT4_FEATURE_INCOMPAT_FILETYPE| \
1509                                          EXT4_FEATURE_INCOMPAT_RECOVER| \
1510                                          EXT4_FEATURE_INCOMPAT_META_BG| \
1511                                          EXT4_FEATURE_INCOMPAT_EXTENTS| \
1512                                          EXT4_FEATURE_INCOMPAT_64BIT| \
1513                                          EXT4_FEATURE_INCOMPAT_FLEX_BG| \
1514                                          EXT4_FEATURE_INCOMPAT_MMP)
1515 #define EXT4_FEATURE_RO_COMPAT_SUPP     (EXT4_FEATURE_RO_COMPAT_SPARSE_SUPER| \
1516                                          EXT4_FEATURE_RO_COMPAT_LARGE_FILE| \
1517                                          EXT4_FEATURE_RO_COMPAT_GDT_CSUM| \
1518                                          EXT4_FEATURE_RO_COMPAT_DIR_NLINK | \
1519                                          EXT4_FEATURE_RO_COMPAT_EXTRA_ISIZE | \
1520                                          EXT4_FEATURE_RO_COMPAT_BTREE_DIR |\
1521                                          EXT4_FEATURE_RO_COMPAT_HUGE_FILE |\
1522                                          EXT4_FEATURE_RO_COMPAT_BIGALLOC |\
1523                                          EXT4_FEATURE_RO_COMPAT_METADATA_CSUM|\
1524                                          EXT4_FEATURE_RO_COMPAT_QUOTA)
1525
1526 /*
1527  * Default values for user and/or group using reserved blocks
1528  */
1529 #define EXT4_DEF_RESUID         0
1530 #define EXT4_DEF_RESGID         0
1531
1532 #define EXT4_DEF_INODE_READAHEAD_BLKS   32
1533
1534 /*
1535  * Default mount options
1536  */
1537 #define EXT4_DEFM_DEBUG         0x0001
1538 #define EXT4_DEFM_BSDGROUPS     0x0002
1539 #define EXT4_DEFM_XATTR_USER    0x0004
1540 #define EXT4_DEFM_ACL           0x0008
1541 #define EXT4_DEFM_UID16         0x0010
1542 #define EXT4_DEFM_JMODE         0x0060
1543 #define EXT4_DEFM_JMODE_DATA    0x0020
1544 #define EXT4_DEFM_JMODE_ORDERED 0x0040
1545 #define EXT4_DEFM_JMODE_WBACK   0x0060
1546 #define EXT4_DEFM_NOBARRIER     0x0100
1547 #define EXT4_DEFM_BLOCK_VALIDITY 0x0200
1548 #define EXT4_DEFM_DISCARD       0x0400
1549 #define EXT4_DEFM_NODELALLOC    0x0800
1550
1551 /*
1552  * Default journal batch times
1553  */
1554 #define EXT4_DEF_MIN_BATCH_TIME 0
1555 #define EXT4_DEF_MAX_BATCH_TIME 15000 /* 15ms */
1556
1557 /*
1558  * Minimum number of groups in a flexgroup before we separate out
1559  * directories into the first block group of a flexgroup
1560  */
1561 #define EXT4_FLEX_SIZE_DIR_ALLOC_SCHEME 4
1562
1563 /*
1564  * Structure of a directory entry
1565  */
1566 #define EXT4_NAME_LEN 255
1567
1568 struct ext4_dir_entry {
1569         __le32  inode;                  /* Inode number */
1570         __le16  rec_len;                /* Directory entry length */
1571         __le16  name_len;               /* Name length */
1572         char    name[EXT4_NAME_LEN];    /* File name */
1573 };
1574
1575 /*
1576  * The new version of the directory entry.  Since EXT4 structures are
1577  * stored in intel byte order, and the name_len field could never be
1578  * bigger than 255 chars, it's safe to reclaim the extra byte for the
1579  * file_type field.
1580  */
1581 struct ext4_dir_entry_2 {
1582         __le32  inode;                  /* Inode number */
1583         __le16  rec_len;                /* Directory entry length */
1584         __u8    name_len;               /* Name length */
1585         __u8    file_type;
1586         char    name[EXT4_NAME_LEN];    /* File name */
1587 };
1588
1589 /*
1590  * This is a bogus directory entry at the end of each leaf block that
1591  * records checksums.
1592  */
1593 struct ext4_dir_entry_tail {
1594         __le32  det_reserved_zero1;     /* Pretend to be unused */
1595         __le16  det_rec_len;            /* 12 */
1596         __u8    det_reserved_zero2;     /* Zero name length */
1597         __u8    det_reserved_ft;        /* 0xDE, fake file type */
1598         __le32  det_checksum;           /* crc32c(uuid+inum+dirblock) */
1599 };
1600
1601 /*
1602  * Ext4 directory file types.  Only the low 3 bits are used.  The
1603  * other bits are reserved for now.
1604  */
1605 #define EXT4_FT_UNKNOWN         0
1606 #define EXT4_FT_REG_FILE        1
1607 #define EXT4_FT_DIR             2
1608 #define EXT4_FT_CHRDEV          3
1609 #define EXT4_FT_BLKDEV          4
1610 #define EXT4_FT_FIFO            5
1611 #define EXT4_FT_SOCK            6
1612 #define EXT4_FT_SYMLINK         7
1613
1614 #define EXT4_FT_MAX             8
1615
1616 #define EXT4_FT_DIR_CSUM        0xDE
1617
1618 /*
1619  * EXT4_DIR_PAD defines the directory entries boundaries
1620  *
1621  * NOTE: It must be a multiple of 4
1622  */
1623 #define EXT4_DIR_PAD                    4
1624 #define EXT4_DIR_ROUND                  (EXT4_DIR_PAD - 1)
1625 #define EXT4_DIR_REC_LEN(name_len)      (((name_len) + 8 + EXT4_DIR_ROUND) & \
1626                                          ~EXT4_DIR_ROUND)
1627 #define EXT4_MAX_REC_LEN                ((1<<16)-1)
1628
1629 /*
1630  * If we ever get support for fs block sizes > page_size, we'll need
1631  * to remove the #if statements in the next two functions...
1632  */
1633 static inline unsigned int
1634 ext4_rec_len_from_disk(__le16 dlen, unsigned blocksize)
1635 {
1636         unsigned len = le16_to_cpu(dlen);
1637
1638 #if (PAGE_CACHE_SIZE >= 65536)
1639         if (len == EXT4_MAX_REC_LEN || len == 0)
1640                 return blocksize;
1641         return (len & 65532) | ((len & 3) << 16);
1642 #else
1643         return len;
1644 #endif
1645 }
1646
1647 static inline __le16 ext4_rec_len_to_disk(unsigned len, unsigned blocksize)
1648 {
1649         if ((len > blocksize) || (blocksize > (1 << 18)) || (len & 3))
1650                 BUG();
1651 #if (PAGE_CACHE_SIZE >= 65536)
1652         if (len < 65536)
1653                 return cpu_to_le16(len);
1654         if (len == blocksize) {
1655                 if (blocksize == 65536)
1656                         return cpu_to_le16(EXT4_MAX_REC_LEN);
1657                 else
1658                         return cpu_to_le16(0);
1659         }
1660         return cpu_to_le16((len & 65532) | ((len >> 16) & 3));
1661 #else
1662         return cpu_to_le16(len);
1663 #endif
1664 }
1665
1666 /*
1667  * Hash Tree Directory indexing
1668  * (c) Daniel Phillips, 2001
1669  */
1670
1671 #define is_dx(dir) (EXT4_HAS_COMPAT_FEATURE(dir->i_sb, \
1672                                       EXT4_FEATURE_COMPAT_DIR_INDEX) && \
1673                     ext4_test_inode_flag((dir), EXT4_INODE_INDEX))
1674 #define EXT4_DIR_LINK_MAX(dir) (!is_dx(dir) && (dir)->i_nlink >= EXT4_LINK_MAX)
1675 #define EXT4_DIR_LINK_EMPTY(dir) ((dir)->i_nlink == 2 || (dir)->i_nlink == 1)
1676
1677 /* Legal values for the dx_root hash_version field: */
1678
1679 #define DX_HASH_LEGACY          0
1680 #define DX_HASH_HALF_MD4        1
1681 #define DX_HASH_TEA             2
1682 #define DX_HASH_LEGACY_UNSIGNED 3
1683 #define DX_HASH_HALF_MD4_UNSIGNED       4
1684 #define DX_HASH_TEA_UNSIGNED            5
1685
1686 static inline u32 ext4_chksum(struct ext4_sb_info *sbi, u32 crc,
1687                               const void *address, unsigned int length)
1688 {
1689         struct {
1690                 struct shash_desc shash;
1691                 char ctx[4];
1692         } desc;
1693         int err;
1694
1695         BUG_ON(crypto_shash_descsize(sbi->s_chksum_driver)!=sizeof(desc.ctx));
1696
1697         desc.shash.tfm = sbi->s_chksum_driver;
1698         desc.shash.flags = 0;
1699         *(u32 *)desc.ctx = crc;
1700
1701         err = crypto_shash_update(&desc.shash, address, length);
1702         BUG_ON(err);
1703
1704         return *(u32 *)desc.ctx;
1705 }
1706
1707 #ifdef __KERNEL__
1708
1709 /* hash info structure used by the directory hash */
1710 struct dx_hash_info
1711 {
1712         u32             hash;
1713         u32             minor_hash;
1714         int             hash_version;
1715         u32             *seed;
1716 };
1717
1718
1719 /* 32 and 64 bit signed EOF for dx directories */
1720 #define EXT4_HTREE_EOF_32BIT   ((1UL  << (32 - 1)) - 1)
1721 #define EXT4_HTREE_EOF_64BIT   ((1ULL << (64 - 1)) - 1)
1722
1723
1724 /*
1725  * Control parameters used by ext4_htree_next_block
1726  */
1727 #define HASH_NB_ALWAYS          1
1728
1729
1730 /*
1731  * Describe an inode's exact location on disk and in memory
1732  */
1733 struct ext4_iloc
1734 {
1735         struct buffer_head *bh;
1736         unsigned long offset;
1737         ext4_group_t block_group;
1738 };
1739
1740 static inline struct ext4_inode *ext4_raw_inode(struct ext4_iloc *iloc)
1741 {
1742         return (struct ext4_inode *) (iloc->bh->b_data + iloc->offset);
1743 }
1744
1745 /*
1746  * This structure is stuffed into the struct file's private_data field
1747  * for directories.  It is where we put information so that we can do
1748  * readdir operations in hash tree order.
1749  */
1750 struct dir_private_info {
1751         struct rb_root  root;
1752         struct rb_node  *curr_node;
1753         struct fname    *extra_fname;
1754         loff_t          last_pos;
1755         __u32           curr_hash;
1756         __u32           curr_minor_hash;
1757         __u32           next_hash;
1758 };
1759
1760 /* calculate the first block number of the group */
1761 static inline ext4_fsblk_t
1762 ext4_group_first_block_no(struct super_block *sb, ext4_group_t group_no)
1763 {
1764         return group_no * (ext4_fsblk_t)EXT4_BLOCKS_PER_GROUP(sb) +
1765                 le32_to_cpu(EXT4_SB(sb)->s_es->s_first_data_block);
1766 }
1767
1768 /*
1769  * Special error return code only used by dx_probe() and its callers.
1770  */
1771 #define ERR_BAD_DX_DIR  -75000
1772
1773 void ext4_get_group_no_and_offset(struct super_block *sb, ext4_fsblk_t blocknr,
1774                         ext4_group_t *blockgrpp, ext4_grpblk_t *offsetp);
1775
1776 /*
1777  * Timeout and state flag for lazy initialization inode thread.
1778  */
1779 #define EXT4_DEF_LI_WAIT_MULT                   10
1780 #define EXT4_DEF_LI_MAX_START_DELAY             5
1781 #define EXT4_LAZYINIT_QUIT                      0x0001
1782 #define EXT4_LAZYINIT_RUNNING                   0x0002
1783
1784 /*
1785  * Lazy inode table initialization info
1786  */
1787 struct ext4_lazy_init {
1788         unsigned long           li_state;
1789         struct list_head        li_request_list;
1790         struct mutex            li_list_mtx;
1791 };
1792
1793 struct ext4_li_request {
1794         struct super_block      *lr_super;
1795         struct ext4_sb_info     *lr_sbi;
1796         ext4_group_t            lr_next_group;
1797         struct list_head        lr_request;
1798         unsigned long           lr_next_sched;
1799         unsigned long           lr_timeout;
1800 };
1801
1802 struct ext4_features {
1803         struct kobject f_kobj;
1804         struct completion f_kobj_unregister;
1805 };
1806
1807 /*
1808  * This structure will be used for multiple mount protection. It will be
1809  * written into the block number saved in the s_mmp_block field in the
1810  * superblock. Programs that check MMP should assume that if
1811  * SEQ_FSCK (or any unknown code above SEQ_MAX) is present then it is NOT safe
1812  * to use the filesystem, regardless of how old the timestamp is.
1813  */
1814 #define EXT4_MMP_MAGIC     0x004D4D50U /* ASCII for MMP */
1815 #define EXT4_MMP_SEQ_CLEAN 0xFF4D4D50U /* mmp_seq value for clean unmount */
1816 #define EXT4_MMP_SEQ_FSCK  0xE24D4D50U /* mmp_seq value when being fscked */
1817 #define EXT4_MMP_SEQ_MAX   0xE24D4D4FU /* maximum valid mmp_seq value */
1818
1819 struct mmp_struct {
1820         __le32  mmp_magic;              /* Magic number for MMP */
1821         __le32  mmp_seq;                /* Sequence no. updated periodically */
1822
1823         /*
1824          * mmp_time, mmp_nodename & mmp_bdevname are only used for information
1825          * purposes and do not affect the correctness of the algorithm
1826          */
1827         __le64  mmp_time;               /* Time last updated */
1828         char    mmp_nodename[64];       /* Node which last updated MMP block */
1829         char    mmp_bdevname[32];       /* Bdev which last updated MMP block */
1830
1831         /*
1832          * mmp_check_interval is used to verify if the MMP block has been
1833          * updated on the block device. The value is updated based on the
1834          * maximum time to write the MMP block during an update cycle.
1835          */
1836         __le16  mmp_check_interval;
1837
1838         __le16  mmp_pad1;
1839         __le32  mmp_pad2[226];
1840         __le32  mmp_checksum;           /* crc32c(uuid+mmp_block) */
1841 };
1842
1843 /* arguments passed to the mmp thread */
1844 struct mmpd_data {
1845         struct buffer_head *bh; /* bh from initial read_mmp_block() */
1846         struct super_block *sb;  /* super block of the fs */
1847 };
1848
1849 /*
1850  * Check interval multiplier
1851  * The MMP block is written every update interval and initially checked every
1852  * update interval x the multiplier (the value is then adapted based on the
1853  * write latency). The reason is that writes can be delayed under load and we
1854  * don't want readers to incorrectly assume that the filesystem is no longer
1855  * in use.
1856  */
1857 #define EXT4_MMP_CHECK_MULT             2UL
1858
1859 /*
1860  * Minimum interval for MMP checking in seconds.
1861  */
1862 #define EXT4_MMP_MIN_CHECK_INTERVAL     5UL
1863
1864 /*
1865  * Maximum interval for MMP checking in seconds.
1866  */
1867 #define EXT4_MMP_MAX_CHECK_INTERVAL     300UL
1868
1869 /*
1870  * Function prototypes
1871  */
1872
1873 /*
1874  * Ok, these declarations are also in <linux/kernel.h> but none of the
1875  * ext4 source programs needs to include it so they are duplicated here.
1876  */
1877 # define NORET_TYPE     /**/
1878 # define ATTRIB_NORET   __attribute__((noreturn))
1879 # define NORET_AND      noreturn,
1880
1881 /* bitmap.c */
1882 extern unsigned int ext4_count_free(char *bitmap, unsigned numchars);
1883 void ext4_inode_bitmap_csum_set(struct super_block *sb, ext4_group_t group,
1884                                 struct ext4_group_desc *gdp,
1885                                 struct buffer_head *bh, int sz);
1886 int ext4_inode_bitmap_csum_verify(struct super_block *sb, ext4_group_t group,
1887                                   struct ext4_group_desc *gdp,
1888                                   struct buffer_head *bh, int sz);
1889 void ext4_block_bitmap_csum_set(struct super_block *sb, ext4_group_t group,
1890                                 struct ext4_group_desc *gdp,
1891                                 struct buffer_head *bh);
1892 int ext4_block_bitmap_csum_verify(struct super_block *sb, ext4_group_t group,
1893                                   struct ext4_group_desc *gdp,
1894                                   struct buffer_head *bh);
1895
1896 /* balloc.c */
1897 extern void ext4_validate_block_bitmap(struct super_block *sb,
1898                                        struct ext4_group_desc *desc,
1899                                        unsigned int block_group,
1900                                        struct buffer_head *bh);
1901 extern unsigned int ext4_block_group(struct super_block *sb,
1902                         ext4_fsblk_t blocknr);
1903 extern ext4_grpblk_t ext4_block_group_offset(struct super_block *sb,
1904                         ext4_fsblk_t blocknr);
1905 extern int ext4_bg_has_super(struct super_block *sb, ext4_group_t group);
1906 extern unsigned long ext4_bg_num_gdb(struct super_block *sb,
1907                         ext4_group_t group);
1908 extern ext4_fsblk_t ext4_new_meta_blocks(handle_t *handle, struct inode *inode,
1909                                          ext4_fsblk_t goal,
1910                                          unsigned int flags,
1911                                          unsigned long *count,
1912                                          int *errp);
1913 extern int ext4_claim_free_clusters(struct ext4_sb_info *sbi,
1914                                     s64 nclusters, unsigned int flags);
1915 extern ext4_fsblk_t ext4_count_free_clusters(struct super_block *);
1916 extern void ext4_check_blocks_bitmap(struct super_block *);
1917 extern struct ext4_group_desc * ext4_get_group_desc(struct super_block * sb,
1918                                                     ext4_group_t block_group,
1919                                                     struct buffer_head ** bh);
1920 extern int ext4_should_retry_alloc(struct super_block *sb, int *retries);
1921
1922 extern struct buffer_head *ext4_read_block_bitmap_nowait(struct super_block *sb,
1923                                                 ext4_group_t block_group);
1924 extern int ext4_wait_block_bitmap(struct super_block *sb,
1925                                   ext4_group_t block_group,
1926                                   struct buffer_head *bh);
1927 extern struct buffer_head *ext4_read_block_bitmap(struct super_block *sb,
1928                                                   ext4_group_t block_group);
1929 extern void ext4_init_block_bitmap(struct super_block *sb,
1930                                    struct buffer_head *bh,
1931                                    ext4_group_t group,
1932                                    struct ext4_group_desc *desc);
1933 extern unsigned ext4_free_clusters_after_init(struct super_block *sb,
1934                                               ext4_group_t block_group,
1935                                               struct ext4_group_desc *gdp);
1936 extern unsigned ext4_num_overhead_clusters(struct super_block *sb,
1937                                            ext4_group_t block_group,
1938                                            struct ext4_group_desc *gdp);
1939 ext4_fsblk_t ext4_inode_to_goal_block(struct inode *);
1940
1941 /* dir.c */
1942 extern int __ext4_check_dir_entry(const char *, unsigned int, struct inode *,
1943                                   struct file *,
1944                                   struct ext4_dir_entry_2 *,
1945                                   struct buffer_head *, unsigned int);
1946 #define ext4_check_dir_entry(dir, filp, de, bh, offset)                 \
1947         unlikely(__ext4_check_dir_entry(__func__, __LINE__, (dir), (filp), \
1948                                         (de), (bh), (offset)))
1949 extern int ext4_htree_store_dirent(struct file *dir_file, __u32 hash,
1950                                     __u32 minor_hash,
1951                                     struct ext4_dir_entry_2 *dirent);
1952 extern void ext4_htree_free_dir_info(struct dir_private_info *p);
1953
1954 /* fsync.c */
1955 extern int ext4_sync_file(struct file *, loff_t, loff_t, int);
1956 extern int ext4_flush_unwritten_io(struct inode *);
1957
1958 /* hash.c */
1959 extern int ext4fs_dirhash(const char *name, int len, struct
1960                           dx_hash_info *hinfo);
1961
1962 /* ialloc.c */
1963 extern struct inode *ext4_new_inode(handle_t *, struct inode *, umode_t,
1964                                     const struct qstr *qstr, __u32 goal,
1965                                     uid_t *owner);
1966 extern void ext4_free_inode(handle_t *, struct inode *);
1967 extern struct inode * ext4_orphan_get(struct super_block *, unsigned long);
1968 extern unsigned long ext4_count_free_inodes(struct super_block *);
1969 extern unsigned long ext4_count_dirs(struct super_block *);
1970 extern void ext4_check_inodes_bitmap(struct super_block *);
1971 extern void ext4_mark_bitmap_end(int start_bit, int end_bit, char *bitmap);
1972 extern int ext4_init_inode_table(struct super_block *sb,
1973                                  ext4_group_t group, int barrier);
1974 extern void ext4_end_bitmap_read(struct buffer_head *bh, int uptodate);
1975
1976 /* mballoc.c */
1977 extern long ext4_mb_stats;
1978 extern long ext4_mb_max_to_scan;
1979 extern int ext4_mb_init(struct super_block *);
1980 extern int ext4_mb_release(struct super_block *);
1981 extern ext4_fsblk_t ext4_mb_new_blocks(handle_t *,
1982                                 struct ext4_allocation_request *, int *);
1983 extern int ext4_mb_reserve_blocks(struct super_block *, int);
1984 extern void ext4_discard_preallocations(struct inode *);
1985 extern int __init ext4_init_mballoc(void);
1986 extern void ext4_exit_mballoc(void);
1987 extern void ext4_free_blocks(handle_t *handle, struct inode *inode,
1988                              struct buffer_head *bh, ext4_fsblk_t block,
1989                              unsigned long count, int flags);
1990 extern int ext4_mb_alloc_groupinfo(struct super_block *sb,
1991                                    ext4_group_t ngroups);
1992 extern int ext4_mb_add_groupinfo(struct super_block *sb,
1993                 ext4_group_t i, struct ext4_group_desc *desc);
1994 extern int ext4_group_add_blocks(handle_t *handle, struct super_block *sb,
1995                                 ext4_fsblk_t block, unsigned long count);
1996 extern int ext4_trim_fs(struct super_block *, struct fstrim_range *);
1997
1998 /* inode.c */
1999 struct buffer_head *ext4_getblk(handle_t *, struct inode *,
2000                                                 ext4_lblk_t, int, int *);
2001 struct buffer_head *ext4_bread(handle_t *, struct inode *,
2002                                                 ext4_lblk_t, int, int *);
2003 int ext4_get_block(struct inode *inode, sector_t iblock,
2004                                 struct buffer_head *bh_result, int create);
2005
2006 extern struct inode *ext4_iget(struct super_block *, unsigned long);
2007 extern int  ext4_write_inode(struct inode *, struct writeback_control *);
2008 extern int  ext4_setattr(struct dentry *, struct iattr *);
2009 extern int  ext4_getattr(struct vfsmount *mnt, struct dentry *dentry,
2010                                 struct kstat *stat);
2011 extern void ext4_evict_inode(struct inode *);
2012 extern void ext4_clear_inode(struct inode *);
2013 extern int  ext4_sync_inode(handle_t *, struct inode *);
2014 extern void ext4_dirty_inode(struct inode *, int);
2015 extern int ext4_change_inode_journal_flag(struct inode *, int);
2016 extern int ext4_get_inode_loc(struct inode *, struct ext4_iloc *);
2017 extern int ext4_can_truncate(struct inode *inode);
2018 extern void ext4_truncate(struct inode *);
2019 extern int ext4_punch_hole(struct file *file, loff_t offset, loff_t length);
2020 extern int ext4_truncate_restart_trans(handle_t *, struct inode *, int nblocks);
2021 extern void ext4_set_inode_flags(struct inode *);
2022 extern void ext4_get_inode_flags(struct ext4_inode_info *);
2023 extern int ext4_alloc_da_blocks(struct inode *inode);
2024 extern void ext4_set_aops(struct inode *inode);
2025 extern int ext4_writepage_trans_blocks(struct inode *);
2026 extern int ext4_chunk_trans_blocks(struct inode *, int nrblocks);
2027 extern int ext4_discard_partial_page_buffers(handle_t *handle,
2028                 struct address_space *mapping, loff_t from,
2029                 loff_t length, int flags);
2030 extern int ext4_page_mkwrite(struct vm_area_struct *vma, struct vm_fault *vmf);
2031 extern qsize_t *ext4_get_reserved_space(struct inode *inode);
2032 extern void ext4_da_update_reserve_space(struct inode *inode,
2033                                         int used, int quota_claim);
2034
2035 /* indirect.c */
2036 extern int ext4_ind_map_blocks(handle_t *handle, struct inode *inode,
2037                                 struct ext4_map_blocks *map, int flags);
2038 extern ssize_t ext4_ind_direct_IO(int rw, struct kiocb *iocb,
2039                                 const struct iovec *iov, loff_t offset,
2040                                 unsigned long nr_segs);
2041 extern int ext4_ind_calc_metadata_amount(struct inode *inode, sector_t lblock);
2042 extern int ext4_ind_trans_blocks(struct inode *inode, int nrblocks, int chunk);
2043 extern void ext4_ind_truncate(struct inode *inode);
2044
2045 /* ioctl.c */
2046 extern long ext4_ioctl(struct file *, unsigned int, unsigned long);
2047 extern long ext4_compat_ioctl(struct file *, unsigned int, unsigned long);
2048
2049 /* migrate.c */
2050 extern int ext4_ext_migrate(struct inode *);
2051
2052 /* namei.c */
2053 extern int ext4_dirent_csum_verify(struct inode *inode,
2054                                    struct ext4_dir_entry *dirent);
2055 extern int ext4_orphan_add(handle_t *, struct inode *);
2056 extern int ext4_orphan_del(handle_t *, struct inode *);
2057 extern int ext4_htree_fill_tree(struct file *dir_file, __u32 start_hash,
2058                                 __u32 start_minor_hash, __u32 *next_hash);
2059
2060 /* resize.c */
2061 extern int ext4_group_add(struct super_block *sb,
2062                                 struct ext4_new_group_data *input);
2063 extern int ext4_group_extend(struct super_block *sb,
2064                                 struct ext4_super_block *es,
2065                                 ext4_fsblk_t n_blocks_count);
2066 extern int ext4_resize_fs(struct super_block *sb, ext4_fsblk_t n_blocks_count);
2067
2068 /* super.c */
2069 extern int ext4_calculate_overhead(struct super_block *sb);
2070 extern int ext4_superblock_csum_verify(struct super_block *sb,
2071                                        struct ext4_super_block *es);
2072 extern void ext4_superblock_csum_set(struct super_block *sb);
2073 extern void *ext4_kvmalloc(size_t size, gfp_t flags);
2074 extern void *ext4_kvzalloc(size_t size, gfp_t flags);
2075 extern void ext4_kvfree(void *ptr);
2076 extern int ext4_alloc_flex_bg_array(struct super_block *sb,
2077                                     ext4_group_t ngroup);
2078 extern __printf(4, 5)
2079 void __ext4_error(struct super_block *, const char *, unsigned int,
2080                   const char *, ...);
2081 #define ext4_error(sb, message...)      __ext4_error(sb, __func__,      \
2082                                                      __LINE__, ## message)
2083 extern __printf(5, 6)
2084 void ext4_error_inode(struct inode *, const char *, unsigned int, ext4_fsblk_t,
2085                       const char *, ...);
2086 extern __printf(5, 6)
2087 void ext4_error_file(struct file *, const char *, unsigned int, ext4_fsblk_t,
2088                      const char *, ...);
2089 extern void __ext4_std_error(struct super_block *, const char *,
2090                              unsigned int, int);
2091 extern __printf(4, 5)
2092 void __ext4_abort(struct super_block *, const char *, unsigned int,
2093                   const char *, ...);
2094 #define ext4_abort(sb, message...)      __ext4_abort(sb, __func__, \
2095                                                        __LINE__, ## message)
2096 extern __printf(4, 5)
2097 void __ext4_warning(struct super_block *, const char *, unsigned int,
2098                     const char *, ...);
2099 #define ext4_warning(sb, message...)    __ext4_warning(sb, __func__, \
2100                                                        __LINE__, ## message)
2101 extern __printf(3, 4)
2102 void ext4_msg(struct super_block *, const char *, const char *, ...);
2103 extern void __dump_mmp_msg(struct super_block *, struct mmp_struct *mmp,
2104                            const char *, unsigned int, const char *);
2105 #define dump_mmp_msg(sb, mmp, msg)      __dump_mmp_msg(sb, mmp, __func__, \
2106                                                        __LINE__, msg)
2107 extern __printf(7, 8)
2108 void __ext4_grp_locked_error(const char *, unsigned int,
2109                              struct super_block *, ext4_group_t,
2110                              unsigned long, ext4_fsblk_t,
2111                              const char *, ...);
2112 #define ext4_grp_locked_error(sb, grp, message...) \
2113         __ext4_grp_locked_error(__func__, __LINE__, (sb), (grp), ## message)
2114 extern void ext4_update_dynamic_rev(struct super_block *sb);
2115 extern int ext4_update_compat_feature(handle_t *handle, struct super_block *sb,
2116                                         __u32 compat);
2117 extern int ext4_update_rocompat_feature(handle_t *handle,
2118                                         struct super_block *sb, __u32 rocompat);
2119 extern int ext4_update_incompat_feature(handle_t *handle,
2120                                         struct super_block *sb, __u32 incompat);
2121 extern ext4_fsblk_t ext4_block_bitmap(struct super_block *sb,
2122                                       struct ext4_group_desc *bg);
2123 extern ext4_fsblk_t ext4_inode_bitmap(struct super_block *sb,
2124                                       struct ext4_group_desc *bg);
2125 extern ext4_fsblk_t ext4_inode_table(struct super_block *sb,
2126                                      struct ext4_group_desc *bg);
2127 extern __u32 ext4_free_group_clusters(struct super_block *sb,
2128                                       struct ext4_group_desc *bg);
2129 extern __u32 ext4_free_inodes_count(struct super_block *sb,
2130                                  struct ext4_group_desc *bg);
2131 extern __u32 ext4_used_dirs_count(struct super_block *sb,
2132                                 struct ext4_group_desc *bg);
2133 extern __u32 ext4_itable_unused_count(struct super_block *sb,
2134                                    struct ext4_group_desc *bg);
2135 extern void ext4_block_bitmap_set(struct super_block *sb,
2136                                   struct ext4_group_desc *bg, ext4_fsblk_t blk);
2137 extern void ext4_inode_bitmap_set(struct super_block *sb,
2138                                   struct ext4_group_desc *bg, ext4_fsblk_t blk);
2139 extern void ext4_inode_table_set(struct super_block *sb,
2140                                  struct ext4_group_desc *bg, ext4_fsblk_t blk);
2141 extern void ext4_free_group_clusters_set(struct super_block *sb,
2142                                          struct ext4_group_desc *bg,
2143                                          __u32 count);
2144 extern void ext4_free_inodes_set(struct super_block *sb,
2145                                 struct ext4_group_desc *bg, __u32 count);
2146 extern void ext4_used_dirs_set(struct super_block *sb,
2147                                 struct ext4_group_desc *bg, __u32 count);
2148 extern void ext4_itable_unused_set(struct super_block *sb,
2149                                    struct ext4_group_desc *bg, __u32 count);
2150 extern int ext4_group_desc_csum_verify(struct super_block *sb, __u32 group,
2151                                        struct ext4_group_desc *gdp);
2152 extern void ext4_group_desc_csum_set(struct super_block *sb, __u32 group,
2153                                      struct ext4_group_desc *gdp);
2154
2155 static inline int ext4_has_group_desc_csum(struct super_block *sb)
2156 {
2157         return EXT4_HAS_RO_COMPAT_FEATURE(sb,
2158                                           EXT4_FEATURE_RO_COMPAT_GDT_CSUM |
2159                                           EXT4_FEATURE_RO_COMPAT_METADATA_CSUM);
2160 }
2161
2162 static inline ext4_fsblk_t ext4_blocks_count(struct ext4_super_block *es)
2163 {
2164         return ((ext4_fsblk_t)le32_to_cpu(es->s_blocks_count_hi) << 32) |
2165                 le32_to_cpu(es->s_blocks_count_lo);
2166 }
2167
2168 static inline ext4_fsblk_t ext4_r_blocks_count(struct ext4_super_block *es)
2169 {
2170         return ((ext4_fsblk_t)le32_to_cpu(es->s_r_blocks_count_hi) << 32) |
2171                 le32_to_cpu(es->s_r_blocks_count_lo);
2172 }
2173
2174 static inline ext4_fsblk_t ext4_free_blocks_count(struct ext4_super_block *es)
2175 {
2176         return ((ext4_fsblk_t)le32_to_cpu(es->s_free_blocks_count_hi) << 32) |
2177                 le32_to_cpu(es->s_free_blocks_count_lo);
2178 }
2179
2180 static inline void ext4_blocks_count_set(struct ext4_super_block *es,
2181                                          ext4_fsblk_t blk)
2182 {
2183         es->s_blocks_count_lo = cpu_to_le32((u32)blk);
2184         es->s_blocks_count_hi = cpu_to_le32(blk >> 32);
2185 }
2186
2187 static inline void ext4_free_blocks_count_set(struct ext4_super_block *es,
2188                                               ext4_fsblk_t blk)
2189 {
2190         es->s_free_blocks_count_lo = cpu_to_le32((u32)blk);
2191         es->s_free_blocks_count_hi = cpu_to_le32(blk >> 32);
2192 }
2193
2194 static inline void ext4_r_blocks_count_set(struct ext4_super_block *es,
2195                                            ext4_fsblk_t blk)
2196 {
2197         es->s_r_blocks_count_lo = cpu_to_le32((u32)blk);
2198         es->s_r_blocks_count_hi = cpu_to_le32(blk >> 32);
2199 }
2200
2201 static inline loff_t ext4_isize(struct ext4_inode *raw_inode)
2202 {
2203         if (S_ISREG(le16_to_cpu(raw_inode->i_mode)))
2204                 return ((loff_t)le32_to_cpu(raw_inode->i_size_high) << 32) |
2205                         le32_to_cpu(raw_inode->i_size_lo);
2206         else
2207                 return (loff_t) le32_to_cpu(raw_inode->i_size_lo);
2208 }
2209
2210 static inline void ext4_isize_set(struct ext4_inode *raw_inode, loff_t i_size)
2211 {
2212         raw_inode->i_size_lo = cpu_to_le32(i_size);
2213         raw_inode->i_size_high = cpu_to_le32(i_size >> 32);
2214 }
2215
2216 static inline
2217 struct ext4_group_info *ext4_get_group_info(struct super_block *sb,
2218                                             ext4_group_t group)
2219 {
2220          struct ext4_group_info ***grp_info;
2221          long indexv, indexh;
2222          grp_info = EXT4_SB(sb)->s_group_info;
2223          indexv = group >> (EXT4_DESC_PER_BLOCK_BITS(sb));
2224          indexh = group & ((EXT4_DESC_PER_BLOCK(sb)) - 1);
2225          return grp_info[indexv][indexh];
2226 }
2227
2228 /*
2229  * Reading s_groups_count requires using smp_rmb() afterwards.  See
2230  * the locking protocol documented in the comments of ext4_group_add()
2231  * in resize.c
2232  */
2233 static inline ext4_group_t ext4_get_groups_count(struct super_block *sb)
2234 {
2235         ext4_group_t    ngroups = EXT4_SB(sb)->s_groups_count;
2236
2237         smp_rmb();
2238         return ngroups;
2239 }
2240
2241 static inline ext4_group_t ext4_flex_group(struct ext4_sb_info *sbi,
2242                                              ext4_group_t block_group)
2243 {
2244         return block_group >> sbi->s_log_groups_per_flex;
2245 }
2246
2247 static inline unsigned int ext4_flex_bg_size(struct ext4_sb_info *sbi)
2248 {
2249         return 1 << sbi->s_log_groups_per_flex;
2250 }
2251
2252 #define ext4_std_error(sb, errno)                               \
2253 do {                                                            \
2254         if ((errno))                                            \
2255                 __ext4_std_error((sb), __func__, __LINE__, (errno));    \
2256 } while (0)
2257
2258 #ifdef CONFIG_SMP
2259 /* Each CPU can accumulate percpu_counter_batch clusters in their local
2260  * counters. So we need to make sure we have free clusters more
2261  * than percpu_counter_batch  * nr_cpu_ids. Also add a window of 4 times.
2262  */
2263 #define EXT4_FREECLUSTERS_WATERMARK (4 * (percpu_counter_batch * nr_cpu_ids))
2264 #else
2265 #define EXT4_FREECLUSTERS_WATERMARK 0
2266 #endif
2267
2268 static inline void ext4_update_i_disksize(struct inode *inode, loff_t newsize)
2269 {
2270         /*
2271          * XXX: replace with spinlock if seen contended -bzzz
2272          */
2273         down_write(&EXT4_I(inode)->i_data_sem);
2274         if (newsize > EXT4_I(inode)->i_disksize)
2275                 EXT4_I(inode)->i_disksize = newsize;
2276         up_write(&EXT4_I(inode)->i_data_sem);
2277         return ;
2278 }
2279
2280 struct ext4_group_info {
2281         unsigned long   bb_state;
2282         struct rb_root  bb_free_root;
2283         ext4_grpblk_t   bb_first_free;  /* first free block */
2284         ext4_grpblk_t   bb_free;        /* total free blocks */
2285         ext4_grpblk_t   bb_fragments;   /* nr of freespace fragments */
2286         ext4_grpblk_t   bb_largest_free_order;/* order of largest frag in BG */
2287         struct          list_head bb_prealloc_list;
2288 #ifdef DOUBLE_CHECK
2289         void            *bb_bitmap;
2290 #endif
2291         struct rw_semaphore alloc_sem;
2292         ext4_grpblk_t   bb_counters[];  /* Nr of free power-of-two-block
2293                                          * regions, index is order.
2294                                          * bb_counters[3] = 5 means
2295                                          * 5 free 8-block regions. */
2296 };
2297
2298 #define EXT4_GROUP_INFO_NEED_INIT_BIT           0
2299 #define EXT4_GROUP_INFO_WAS_TRIMMED_BIT         1
2300
2301 #define EXT4_MB_GRP_NEED_INIT(grp)      \
2302         (test_bit(EXT4_GROUP_INFO_NEED_INIT_BIT, &((grp)->bb_state)))
2303
2304 #define EXT4_MB_GRP_WAS_TRIMMED(grp)    \
2305         (test_bit(EXT4_GROUP_INFO_WAS_TRIMMED_BIT, &((grp)->bb_state)))
2306 #define EXT4_MB_GRP_SET_TRIMMED(grp)    \
2307         (set_bit(EXT4_GROUP_INFO_WAS_TRIMMED_BIT, &((grp)->bb_state)))
2308 #define EXT4_MB_GRP_CLEAR_TRIMMED(grp)  \
2309         (clear_bit(EXT4_GROUP_INFO_WAS_TRIMMED_BIT, &((grp)->bb_state)))
2310
2311 #define EXT4_MAX_CONTENTION             8
2312 #define EXT4_CONTENTION_THRESHOLD       2
2313
2314 static inline spinlock_t *ext4_group_lock_ptr(struct super_block *sb,
2315                                               ext4_group_t group)
2316 {
2317         return bgl_lock_ptr(EXT4_SB(sb)->s_blockgroup_lock, group);
2318 }
2319
2320 /*
2321  * Returns true if the filesystem is busy enough that attempts to
2322  * access the block group locks has run into contention.
2323  */
2324 static inline int ext4_fs_is_busy(struct ext4_sb_info *sbi)
2325 {
2326         return (atomic_read(&sbi->s_lock_busy) > EXT4_CONTENTION_THRESHOLD);
2327 }
2328
2329 static inline void ext4_lock_group(struct super_block *sb, ext4_group_t group)
2330 {
2331         spinlock_t *lock = ext4_group_lock_ptr(sb, group);
2332         if (spin_trylock(lock))
2333                 /*
2334                  * We're able to grab the lock right away, so drop the
2335                  * lock contention counter.
2336                  */
2337                 atomic_add_unless(&EXT4_SB(sb)->s_lock_busy, -1, 0);
2338         else {
2339                 /*
2340                  * The lock is busy, so bump the contention counter,
2341                  * and then wait on the spin lock.
2342                  */
2343                 atomic_add_unless(&EXT4_SB(sb)->s_lock_busy, 1,
2344                                   EXT4_MAX_CONTENTION);
2345                 spin_lock(lock);
2346         }
2347 }
2348
2349 static inline void ext4_unlock_group(struct super_block *sb,
2350                                         ext4_group_t group)
2351 {
2352         spin_unlock(ext4_group_lock_ptr(sb, group));
2353 }
2354
2355 /*
2356  * Block validity checking
2357  */
2358 #define ext4_check_indirect_blockref(inode, bh)                         \
2359         ext4_check_blockref(__func__, __LINE__, inode,                  \
2360                             (__le32 *)(bh)->b_data,                     \
2361                             EXT4_ADDR_PER_BLOCK((inode)->i_sb))
2362
2363 #define ext4_ind_check_inode(inode)                                     \
2364         ext4_check_blockref(__func__, __LINE__, inode,                  \
2365                             EXT4_I(inode)->i_data,                      \
2366                             EXT4_NDIR_BLOCKS)
2367
2368 /*
2369  * Inodes and files operations
2370  */
2371
2372 /* dir.c */
2373 extern const struct file_operations ext4_dir_operations;
2374
2375 /* file.c */
2376 extern const struct inode_operations ext4_file_inode_operations;
2377 extern const struct file_operations ext4_file_operations;
2378 extern loff_t ext4_llseek(struct file *file, loff_t offset, int origin);
2379 extern void ext4_unwritten_wait(struct inode *inode);
2380
2381 /* namei.c */
2382 extern const struct inode_operations ext4_dir_inode_operations;
2383 extern const struct inode_operations ext4_special_inode_operations;
2384 extern struct dentry *ext4_get_parent(struct dentry *child);
2385
2386 /* symlink.c */
2387 extern const struct inode_operations ext4_symlink_inode_operations;
2388 extern const struct inode_operations ext4_fast_symlink_inode_operations;
2389
2390 /* block_validity */
2391 extern void ext4_release_system_zone(struct super_block *sb);
2392 extern int ext4_setup_system_zone(struct super_block *sb);
2393 extern int __init ext4_init_system_zone(void);
2394 extern void ext4_exit_system_zone(void);
2395 extern int ext4_data_block_valid(struct ext4_sb_info *sbi,
2396                                  ext4_fsblk_t start_blk,
2397                                  unsigned int count);
2398 extern int ext4_check_blockref(const char *, unsigned int,
2399                                struct inode *, __le32 *, unsigned int);
2400
2401 /* extents.c */
2402 extern int ext4_ext_tree_init(handle_t *handle, struct inode *);
2403 extern int ext4_ext_writepage_trans_blocks(struct inode *, int);
2404 extern int ext4_ext_index_trans_blocks(struct inode *inode, int nrblocks,
2405                                        int chunk);
2406 extern int ext4_ext_map_blocks(handle_t *handle, struct inode *inode,
2407                                struct ext4_map_blocks *map, int flags);
2408 extern void ext4_ext_truncate(struct inode *);
2409 extern int ext4_ext_punch_hole(struct file *file, loff_t offset,
2410                                 loff_t length);
2411 extern void ext4_ext_init(struct super_block *);
2412 extern void ext4_ext_release(struct super_block *);
2413 extern long ext4_fallocate(struct file *file, int mode, loff_t offset,
2414                           loff_t len);
2415 extern int ext4_convert_unwritten_extents(struct inode *inode, loff_t offset,
2416                           ssize_t len);
2417 extern int ext4_map_blocks(handle_t *handle, struct inode *inode,
2418                            struct ext4_map_blocks *map, int flags);
2419 extern int ext4_fiemap(struct inode *inode, struct fiemap_extent_info *fieinfo,
2420                         __u64 start, __u64 len);
2421 /* move_extent.c */
2422 extern int ext4_move_extents(struct file *o_filp, struct file *d_filp,
2423                              __u64 start_orig, __u64 start_donor,
2424                              __u64 len, __u64 *moved_len);
2425
2426 /* page-io.c */
2427 extern int __init ext4_init_pageio(void);
2428 extern void ext4_add_complete_io(ext4_io_end_t *io_end);
2429 extern void ext4_exit_pageio(void);
2430 extern void ext4_ioend_wait(struct inode *);
2431 extern void ext4_free_io_end(ext4_io_end_t *io);
2432 extern ext4_io_end_t *ext4_init_io_end(struct inode *inode, gfp_t flags);
2433 extern void ext4_io_submit(struct ext4_io_submit *io);
2434 extern int ext4_bio_write_page(struct ext4_io_submit *io,
2435                                struct page *page,
2436                                int len,
2437                                struct writeback_control *wbc);
2438
2439 /* mmp.c */
2440 extern int ext4_multi_mount_protect(struct super_block *, ext4_fsblk_t);
2441 extern void ext4_mmp_csum_set(struct super_block *sb, struct mmp_struct *mmp);
2442 extern int ext4_mmp_csum_verify(struct super_block *sb,
2443                                 struct mmp_struct *mmp);
2444
2445 /* BH_Uninit flag: blocks are allocated but uninitialized on disk */
2446 enum ext4_state_bits {
2447         BH_Uninit       /* blocks are allocated but uninitialized on disk */
2448           = BH_JBDPrivateStart,
2449         BH_AllocFromCluster,    /* allocated blocks were part of already
2450                                  * allocated cluster. Note that this flag will
2451                                  * never, ever appear in a buffer_head's state
2452                                  * flag. See EXT4_MAP_FROM_CLUSTER to see where
2453                                  * this is used. */
2454         BH_Da_Mapped,   /* Delayed allocated block that now has a mapping. This
2455                          * flag is set when ext4_map_blocks is called on a
2456                          * delayed allocated block to get its real mapping. */
2457 };
2458
2459 BUFFER_FNS(Uninit, uninit)
2460 TAS_BUFFER_FNS(Uninit, uninit)
2461 BUFFER_FNS(Da_Mapped, da_mapped)
2462
2463 /*
2464  * Add new method to test wether block and inode bitmaps are properly
2465  * initialized. With uninit_bg reading the block from disk is not enough
2466  * to mark the bitmap uptodate. We need to also zero-out the bitmap
2467  */
2468 #define BH_BITMAP_UPTODATE BH_JBDPrivateStart
2469
2470 static inline int bitmap_uptodate(struct buffer_head *bh)
2471 {
2472         return (buffer_uptodate(bh) &&
2473                         test_bit(BH_BITMAP_UPTODATE, &(bh)->b_state));
2474 }
2475 static inline void set_bitmap_uptodate(struct buffer_head *bh)
2476 {
2477         set_bit(BH_BITMAP_UPTODATE, &(bh)->b_state);
2478 }
2479
2480 /*
2481  * Disable DIO read nolock optimization, so new dioreaders will be forced
2482  * to grab i_mutex
2483  */
2484 static inline void ext4_inode_block_unlocked_dio(struct inode *inode)
2485 {
2486         ext4_set_inode_state(inode, EXT4_STATE_DIOREAD_LOCK);
2487         smp_mb();
2488 }
2489 static inline void ext4_inode_resume_unlocked_dio(struct inode *inode)
2490 {
2491         smp_mb();
2492         ext4_clear_inode_state(inode, EXT4_STATE_DIOREAD_LOCK);
2493 }
2494
2495 #define in_range(b, first, len) ((b) >= (first) && (b) <= (first) + (len) - 1)
2496
2497 /* For ioend & aio unwritten conversion wait queues */
2498 #define EXT4_WQ_HASH_SZ         37
2499 #define ext4_ioend_wq(v)   (&ext4__ioend_wq[((unsigned long)(v)) %\
2500                                             EXT4_WQ_HASH_SZ])
2501 #define ext4_aio_mutex(v)  (&ext4__aio_mutex[((unsigned long)(v)) %\
2502                                              EXT4_WQ_HASH_SZ])
2503 extern wait_queue_head_t ext4__ioend_wq[EXT4_WQ_HASH_SZ];
2504 extern struct mutex ext4__aio_mutex[EXT4_WQ_HASH_SZ];
2505
2506 #define EXT4_RESIZING   0
2507 extern int ext4_resize_begin(struct super_block *sb);
2508 extern void ext4_resize_end(struct super_block *sb);
2509
2510 #endif  /* __KERNEL__ */
2511
2512 #include "ext4_extents.h"
2513
2514 #endif  /* _EXT4_H */