fs/ext4/ext4.h

   1 /*
   2  *  ext4.h
   3  *
   4  * Copyright (C) 1992, 1993, 1994, 1995
   5  * Remy Card (card@masi.ibp.fr)
   6  * Laboratoire MASI - Institut Blaise Pascal
   7  * Universite Pierre et Marie Curie (Paris VI)
   8  *
   9  *  from
  10  *
  11  *  linux/include/linux/minix_fs.h
  12  *
  13  *  Copyright (C) 1991, 1992  Linus Torvalds
  14  */
  15
  16 #ifndef _EXT4_H
  17 #define _EXT4_H
  18
  19 #include <linux/types.h>
  20 #include <linux/blkdev.h>
  21 #include <linux/magic.h>
  22 #include <linux/jbd2.h>
  23 #include <linux/quota.h>
  24 #include <linux/rwsem.h>
  25 #include <linux/rbtree.h>
  26 #include <linux/seqlock.h>
  27 #include <linux/mutex.h>
  28 #include <linux/timer.h>
  29 #include <linux/wait.h>
  30 #include <linux/blockgroup_lock.h>
  31 #include <linux/percpu_counter.h>
  32 #include <crypto/hash.h>
  33 #ifdef __KERNEL__
  34 #include <linux/compat.h>
  35 #endif
  36
  37 /*
  38  * The fourth extended filesystem constants/structures
  39  */
  40
  41 /*
  42  * Define EXT4FS_DEBUG to produce debug messages
  43  */
  44 #undef EXT4FS_DEBUG
  45
  46 /*
  47  * Debug code
  48  */
  49 #ifdef EXT4FS_DEBUG
  50 #define ext4_debug(f, a...)                                             \
  51         do {                                                            \
  52                 printk(KERN_DEBUG "EXT4-fs DEBUG (%s, %d): %s:",        \
  53                         __FILE__, __LINE__, __func__);                  \
  54                 printk(KERN_DEBUG f, ## a);                             \
  55         } while (0)
  56 #else
  57 #define ext4_debug(fmt, ...)    no_printk(fmt, ##__VA_ARGS__)
  58 #endif
  59
  60 /*
  61  * Turn on EXT_DEBUG to get lots of info about extents operations.
  62  */
  63 #define EXT_DEBUG__
  64 #ifdef EXT_DEBUG
  65 #define ext_debug(fmt, ...)     printk(fmt, ##__VA_ARGS__)
  66 #else
  67 #define ext_debug(fmt, ...)     no_printk(fmt, ##__VA_ARGS__)
  68 #endif
  69
  70 #define EXT4_ERROR_INODE(inode, fmt, a...) \
  71         ext4_error_inode((inode), __func__, __LINE__, 0, (fmt), ## a)
  72
  73 #define EXT4_ERROR_INODE_BLOCK(inode, block, fmt, a...)                 \
  74         ext4_error_inode((inode), __func__, __LINE__, (block), (fmt), ## a)
  75
  76 #define EXT4_ERROR_FILE(file, block, fmt, a...)                         \
  77         ext4_error_file((file), __func__, __LINE__, (block), (fmt), ## a)
  78
  79 /* data type for block offset of block group */
  80 typedef int ext4_grpblk_t;
  81
  82 /* data type for filesystem-wide blocks number */
  83 typedef unsigned long long ext4_fsblk_t;
  84
  85 /* data type for file logical block number */
  86 typedef __u32 ext4_lblk_t;
  87
  88 /* data type for block group number */
  89 typedef unsigned int ext4_group_t;
  90
  91 /*
  92  * Flags used in mballoc's allocation_context flags field.
  93  *
  94  * Also used to show what's going on for debugging purposes when the
  95  * flag field is exported via the traceport interface
  96  */
  97
  98 /* prefer goal again. length */
  99 #define EXT4_MB_HINT_MERGE              0x0001
 100 /* blocks already reserved */
 101 #define EXT4_MB_HINT_RESERVED           0x0002
 102 /* metadata is being allocated */
 103 #define EXT4_MB_HINT_METADATA           0x0004
 104 /* first blocks in the file */
 105 #define EXT4_MB_HINT_FIRST              0x0008
 106 /* search for the best chunk */
 107 #define EXT4_MB_HINT_BEST               0x0010
 108 /* data is being allocated */
 109 #define EXT4_MB_HINT_DATA               0x0020
 110 /* don't preallocate (for tails) */
 111 #define EXT4_MB_HINT_NOPREALLOC         0x0040
 112 /* allocate for locality group */
 113 #define EXT4_MB_HINT_GROUP_ALLOC        0x0080
 114 /* allocate goal blocks or none */
 115 #define EXT4_MB_HINT_GOAL_ONLY          0x0100
 116 /* goal is meaningful */
 117 #define EXT4_MB_HINT_TRY_GOAL           0x0200
 118 /* blocks already pre-reserved by delayed allocation */
 119 #define EXT4_MB_DELALLOC_RESERVED       0x0400
 120 /* We are doing stream allocation */
 121 #define EXT4_MB_STREAM_ALLOC            0x0800
 122 /* Use reserved root blocks if needed */
 123 #define EXT4_MB_USE_ROOT_BLOCKS         0x1000
 124
 125 struct ext4_allocation_request {
 126         /* target inode for block we're allocating */
 127         struct inode *inode;
 128         /* how many blocks we want to allocate */
 129         unsigned int len;
 130         /* logical block in target inode */
 131         ext4_lblk_t logical;
 132         /* the closest logical allocated block to the left */
 133         ext4_lblk_t lleft;
 134         /* the closest logical allocated block to the right */
 135         ext4_lblk_t lright;
 136         /* phys. target (a hint) */
 137         ext4_fsblk_t goal;
 138         /* phys. block for the closest logical allocated block to the left */
 139         ext4_fsblk_t pleft;
 140         /* phys. block for the closest logical allocated block to the right */
 141         ext4_fsblk_t pright;
 142         /* flags. see above EXT4_MB_HINT_* */
 143         unsigned int flags;
 144 };
 145
 146 /*
 147  * Logical to physical block mapping, used by ext4_map_blocks()
 148  *
 149  * This structure is used to pass requests into ext4_map_blocks() as
 150  * well as to store the information returned by ext4_map_blocks().  It
 151  * takes less room on the stack than a struct buffer_head.
 152  */
 153 #define EXT4_MAP_NEW            (1 << BH_New)
 154 #define EXT4_MAP_MAPPED         (1 << BH_Mapped)
 155 #define EXT4_MAP_UNWRITTEN      (1 << BH_Unwritten)
 156 #define EXT4_MAP_BOUNDARY       (1 << BH_Boundary)
 157 #define EXT4_MAP_UNINIT         (1 << BH_Uninit)
 158 /* Sometimes (in the bigalloc case, from ext4_da_get_block_prep) the caller of
 159  * ext4_map_blocks wants to know whether or not the underlying cluster has
 160  * already been accounted for. EXT4_MAP_FROM_CLUSTER conveys to the caller that
 161  * the requested mapping was from previously mapped (or delayed allocated)
 162  * cluster. We use BH_AllocFromCluster only for this flag. BH_AllocFromCluster
 163  * should never appear on buffer_head's state flags.
 164  */
 165 #define EXT4_MAP_FROM_CLUSTER   (1 << BH_AllocFromCluster)
 166 #define EXT4_MAP_FLAGS          (EXT4_MAP_NEW | EXT4_MAP_MAPPED |\
 167                                  EXT4_MAP_UNWRITTEN | EXT4_MAP_BOUNDARY |\
 168                                  EXT4_MAP_UNINIT | EXT4_MAP_FROM_CLUSTER)
 169
 170 struct ext4_map_blocks {
 171         ext4_fsblk_t m_pblk;
 172         ext4_lblk_t m_lblk;
 173         unsigned int m_len;
 174         unsigned int m_flags;
 175 };
 176
 177 /*
 178  * For delayed allocation tracking
 179  */
 180 struct mpage_da_data {
 181         struct inode *inode;
 182         sector_t b_blocknr;             /* start block number of extent */
 183         size_t b_size;                  /* size of extent */
 184         unsigned long b_state;          /* state of the extent */
 185         unsigned long first_page, next_page;    /* extent of pages */
 186         struct writeback_control *wbc;
 187         int io_done;
 188         int pages_written;
 189         int retval;
 190 };
 191
 192 /*
 193  * Flags for ext4_io_end->flags
 194  */
 195 #define EXT4_IO_END_UNWRITTEN   0x0001
 196 #define EXT4_IO_END_ERROR       0x0002
 197 #define EXT4_IO_END_QUEUED      0x0004
 198 #define EXT4_IO_END_DIRECT      0x0008
 199
 200 struct ext4_io_page {
 201         struct page     *p_page;
 202         atomic_t        p_count;
 203 };
 204
 205 #define MAX_IO_PAGES 128
 206
 207 /*
 208  * For converting uninitialized extents on a work queue.
 209  *
 210  * 'page' is only used from the writepage() path; 'pages' is only used for
 211  * buffered writes; they are used to keep page references until conversion
 212  * takes place.  For AIO/DIO, neither field is filled in.
 213  */
 214 typedef struct ext4_io_end {
 215         struct list_head        list;           /* per-file finished IO list */
 216         struct inode            *inode;         /* file being written to */
 217         unsigned int            flag;           /* unwritten or not */
 218         struct page             *page;          /* for writepage() path */
 219         loff_t                  offset;         /* offset in the file */
 220         ssize_t                 size;           /* size of the extent */
 221         struct work_struct      work;           /* data work queue */
 222         struct kiocb            *iocb;          /* iocb struct for AIO */
 223         int                     result;         /* error value for AIO */
 224         int                     num_io_pages;   /* for writepages() */
 225         struct ext4_io_page     *pages[MAX_IO_PAGES]; /* for writepages() */
 226 } ext4_io_end_t;
 227
 228 struct ext4_io_submit {
 229         int                     io_op;
 230         struct bio              *io_bio;
 231         ext4_io_end_t           *io_end;
 232         struct ext4_io_page     *io_page;
 233         sector_t                io_next_block;
 234 };
 235
 236 /*
 237  * Special inodes numbers
 238  */
 239 #define EXT4_BAD_INO             1      /* Bad blocks inode */
 240 #define EXT4_ROOT_INO            2      /* Root inode */
 241 #define EXT4_USR_QUOTA_INO       3      /* User quota inode */
 242 #define EXT4_GRP_QUOTA_INO       4      /* Group quota inode */
 243 #define EXT4_BOOT_LOADER_INO     5      /* Boot loader inode */
 244 #define EXT4_UNDEL_DIR_INO       6      /* Undelete directory inode */
 245 #define EXT4_RESIZE_INO          7      /* Reserved group descriptors inode */
 246 #define EXT4_JOURNAL_INO         8      /* Journal inode */
 247
 248 /* First non-reserved inode for old ext4 filesystems */
 249 #define EXT4_GOOD_OLD_FIRST_INO 11
 250
 251 /*
 252  * Maximal count of links to a file
 253  */
 254 #define EXT4_LINK_MAX           65000
 255
 256 /*
 257  * Macro-instructions used to manage several block sizes
 258  */
 259 #define EXT4_MIN_BLOCK_SIZE             1024
 260 #define EXT4_MAX_BLOCK_SIZE             65536
 261 #define EXT4_MIN_BLOCK_LOG_SIZE         10
 262 #define EXT4_MAX_BLOCK_LOG_SIZE         16
 263 #ifdef __KERNEL__
 264 # define EXT4_BLOCK_SIZE(s)             ((s)->s_blocksize)
 265 #else
 266 # define EXT4_BLOCK_SIZE(s)             (EXT4_MIN_BLOCK_SIZE << (s)->s_log_block_size)
 267 #endif
 268 #define EXT4_ADDR_PER_BLOCK(s)          (EXT4_BLOCK_SIZE(s) / sizeof(__u32))
 269 #define EXT4_CLUSTER_SIZE(s)            (EXT4_BLOCK_SIZE(s) << \
 270                                          EXT4_SB(s)->s_cluster_bits)
 271 #ifdef __KERNEL__
 272 # define EXT4_BLOCK_SIZE_BITS(s)        ((s)->s_blocksize_bits)
 273 # define EXT4_CLUSTER_BITS(s)           (EXT4_SB(s)->s_cluster_bits)
 274 #else
 275 # define EXT4_BLOCK_SIZE_BITS(s)        ((s)->s_log_block_size + 10)
 276 #endif
 277 #ifdef __KERNEL__
 278 #define EXT4_ADDR_PER_BLOCK_BITS(s)     (EXT4_SB(s)->s_addr_per_block_bits)
 279 #define EXT4_INODE_SIZE(s)              (EXT4_SB(s)->s_inode_size)
 280 #define EXT4_FIRST_INO(s)               (EXT4_SB(s)->s_first_ino)
 281 #else
 282 #define EXT4_INODE_SIZE(s)      (((s)->s_rev_level == EXT4_GOOD_OLD_REV) ? \
 283                                  EXT4_GOOD_OLD_INODE_SIZE : \
 284                                  (s)->s_inode_size)
 285 #define EXT4_FIRST_INO(s)       (((s)->s_rev_level == EXT4_GOOD_OLD_REV) ? \
 286                                  EXT4_GOOD_OLD_FIRST_INO : \
 287                                  (s)->s_first_ino)
 288 #endif
 289 #define EXT4_BLOCK_ALIGN(size, blkbits)         ALIGN((size), (1 << (blkbits)))
 290
 291 /* Translate a block number to a cluster number */
 292 #define EXT4_B2C(sbi, blk)      ((blk) >> (sbi)->s_cluster_bits)
 293 /* Translate a cluster number to a block number */
 294 #define EXT4_C2B(sbi, cluster)  ((cluster) << (sbi)->s_cluster_bits)
 295 /* Translate # of blks to # of clusters */
 296 #define EXT4_NUM_B2C(sbi, blks) (((blks) + (sbi)->s_cluster_ratio - 1) >> \
 297                                  (sbi)->s_cluster_bits)
 298
 299 /*
 300  * Structure of a blocks group descriptor
 301  */
 302 struct ext4_group_desc
 303 {
 304         __le32  bg_block_bitmap_lo;     /* Blocks bitmap block */
 305         __le32  bg_inode_bitmap_lo;     /* Inodes bitmap block */
 306         __le32  bg_inode_table_lo;      /* Inodes table block */
 307         __le16  bg_free_blocks_count_lo;/* Free blocks count */
 308         __le16  bg_free_inodes_count_lo;/* Free inodes count */
 309         __le16  bg_used_dirs_count_lo;  /* Directories count */
 310         __le16  bg_flags;               /* EXT4_BG_flags (INODE_UNINIT, etc) */
 311         __le32  bg_exclude_bitmap_lo;   /* Exclude bitmap for snapshots */
 312         __le16  bg_block_bitmap_csum_lo;/* crc32c(s_uuid+grp_num+bbitmap) LE */
 313         __le16  bg_inode_bitmap_csum_lo;/* crc32c(s_uuid+grp_num+ibitmap) LE */
 314         __le16  bg_itable_unused_lo;    /* Unused inodes count */
 315         __le16  bg_checksum;            /* crc16(sb_uuid+group+desc) */
 316         __le32  bg_block_bitmap_hi;     /* Blocks bitmap block MSB */
 317         __le32  bg_inode_bitmap_hi;     /* Inodes bitmap block MSB */
 318         __le32  bg_inode_table_hi;      /* Inodes table block MSB */
 319         __le16  bg_free_blocks_count_hi;/* Free blocks count MSB */
 320         __le16  bg_free_inodes_count_hi;/* Free inodes count MSB */
 321         __le16  bg_used_dirs_count_hi;  /* Directories count MSB */
 322         __le16  bg_itable_unused_hi;    /* Unused inodes count MSB */
 323         __le32  bg_exclude_bitmap_hi;   /* Exclude bitmap block MSB */
 324         __le16  bg_block_bitmap_csum_hi;/* crc32c(s_uuid+grp_num+bbitmap) BE */
 325         __le16  bg_inode_bitmap_csum_hi;/* crc32c(s_uuid+grp_num+ibitmap) BE */
 326         __u32   bg_reserved;
 327 };
 328
 329 #define EXT4_BG_INODE_BITMAP_CSUM_HI_END        \
 330         (offsetof(struct ext4_group_desc, bg_inode_bitmap_csum_hi) + \
 331          sizeof(__le16))
 332 #define EXT4_BG_BLOCK_BITMAP_CSUM_HI_END        \
 333         (offsetof(struct ext4_group_desc, bg_block_bitmap_csum_hi) + \
 334          sizeof(__le16))
 335
 336 /*
 337  * Structure of a flex block group info
 338  */
 339
 340 struct flex_groups {
 341         atomic_t free_inodes;
 342         atomic_t free_clusters;
 343         atomic_t used_dirs;
 344 };
 345
 346 #define EXT4_BG_INODE_UNINIT    0x0001 /* Inode table/bitmap not in use */
 347 #define EXT4_BG_BLOCK_UNINIT    0x0002 /* Block bitmap not in use */
 348 #define EXT4_BG_INODE_ZEROED    0x0004 /* On-disk itable initialized to zero */
 349
 350 /*
 351  * Macro-instructions used to manage group descriptors
 352  */
 353 #define EXT4_MIN_DESC_SIZE              32
 354 #define EXT4_MIN_DESC_SIZE_64BIT        64
 355 #define EXT4_MAX_DESC_SIZE              EXT4_MIN_BLOCK_SIZE
 356 #define EXT4_DESC_SIZE(s)               (EXT4_SB(s)->s_desc_size)
 357 #ifdef __KERNEL__
 358 # define EXT4_BLOCKS_PER_GROUP(s)       (EXT4_SB(s)->s_blocks_per_group)
 359 # define EXT4_CLUSTERS_PER_GROUP(s)     (EXT4_SB(s)->s_clusters_per_group)
 360 # define EXT4_DESC_PER_BLOCK(s)         (EXT4_SB(s)->s_desc_per_block)
 361 # define EXT4_INODES_PER_GROUP(s)       (EXT4_SB(s)->s_inodes_per_group)
 362 # define EXT4_DESC_PER_BLOCK_BITS(s)    (EXT4_SB(s)->s_desc_per_block_bits)
 363 #else
 364 # define EXT4_BLOCKS_PER_GROUP(s)       ((s)->s_blocks_per_group)
 365 # define EXT4_DESC_PER_BLOCK(s)         (EXT4_BLOCK_SIZE(s) / EXT4_DESC_SIZE(s))
 366 # define EXT4_INODES_PER_GROUP(s)       ((s)->s_inodes_per_group)
 367 #endif
 368
 369 /*
 370  * Constants relative to the data blocks
 371  */
 372 #define EXT4_NDIR_BLOCKS                12
 373 #define EXT4_IND_BLOCK                  EXT4_NDIR_BLOCKS
 374 #define EXT4_DIND_BLOCK                 (EXT4_IND_BLOCK + 1)
 375 #define EXT4_TIND_BLOCK                 (EXT4_DIND_BLOCK + 1)
 376 #define EXT4_N_BLOCKS                   (EXT4_TIND_BLOCK + 1)
 377
 378 /*
 379  * Inode flags
 380  */
 381 #define EXT4_SECRM_FL                   0x00000001 /* Secure deletion */
 382 #define EXT4_UNRM_FL                    0x00000002 /* Undelete */
 383 #define EXT4_COMPR_FL                   0x00000004 /* Compress file */
 384 #define EXT4_SYNC_FL                    0x00000008 /* Synchronous updates */
 385 #define EXT4_IMMUTABLE_FL               0x00000010 /* Immutable file */
 386 #define EXT4_APPEND_FL                  0x00000020 /* writes to file may only append */
 387 #define EXT4_NODUMP_FL                  0x00000040 /* do not dump file */
 388 #define EXT4_NOATIME_FL                 0x00000080 /* do not update atime */
 389 /* Reserved for compression usage... */
 390 #define EXT4_DIRTY_FL                   0x00000100
 391 #define EXT4_COMPRBLK_FL                0x00000200 /* One or more compressed clusters */
 392 #define EXT4_NOCOMPR_FL                 0x00000400 /* Don't compress */
 393 #define EXT4_ECOMPR_FL                  0x00000800 /* Compression error */
 394 /* End compression flags --- maybe not all used */
 395 #define EXT4_INDEX_FL                   0x00001000 /* hash-indexed directory */
 396 #define EXT4_IMAGIC_FL                  0x00002000 /* AFS directory */
 397 #define EXT4_JOURNAL_DATA_FL            0x00004000 /* file data should be journaled */
 398 #define EXT4_NOTAIL_FL                  0x00008000 /* file tail should not be merged */
 399 #define EXT4_DIRSYNC_FL                 0x00010000 /* dirsync behaviour (directories only) */
 400 #define EXT4_TOPDIR_FL                  0x00020000 /* Top of directory hierarchies*/
 401 #define EXT4_HUGE_FILE_FL               0x00040000 /* Set to each huge file */
 402 #define EXT4_EXTENTS_FL                 0x00080000 /* Inode uses extents */
 403 #define EXT4_EA_INODE_FL                0x00200000 /* Inode used for large EA */
 404 #define EXT4_EOFBLOCKS_FL               0x00400000 /* Blocks allocated beyond EOF */
 405 #define EXT4_INLINE_DATA_FL             0x10000000 /* Inode has inline data. */
 406 #define EXT4_RESERVED_FL                0x80000000 /* reserved for ext4 lib */
 407
 408 #define EXT4_FL_USER_VISIBLE            0x004BDFFF /* User visible flags */
 409 #define EXT4_FL_USER_MODIFIABLE         0x004B80FF /* User modifiable flags */
 410
 411 /* Flags that should be inherited by new inodes from their parent. */
 412 #define EXT4_FL_INHERITED (EXT4_SECRM_FL | EXT4_UNRM_FL | EXT4_COMPR_FL |\
 413                            EXT4_SYNC_FL | EXT4_NODUMP_FL | EXT4_NOATIME_FL |\
 414                            EXT4_NOCOMPR_FL | EXT4_JOURNAL_DATA_FL |\
 415                            EXT4_NOTAIL_FL | EXT4_DIRSYNC_FL)
 416
 417 /* Flags that are appropriate for regular files (all but dir-specific ones). */
 418 #define EXT4_REG_FLMASK (~(EXT4_DIRSYNC_FL | EXT4_TOPDIR_FL))
 419
 420 /* Flags that are appropriate for non-directories/regular files. */
 421 #define EXT4_OTHER_FLMASK (EXT4_NODUMP_FL | EXT4_NOATIME_FL)
 422
 423 /* Mask out flags that are inappropriate for the given type of inode. */
 424 static inline __u32 ext4_mask_flags(umode_t mode, __u32 flags)
 425 {
 426         if (S_ISDIR(mode))
 427                 return flags;
 428         else if (S_ISREG(mode))
 429                 return flags & EXT4_REG_FLMASK;
 430         else
 431                 return flags & EXT4_OTHER_FLMASK;
 432 }
 433
 434 /*
 435  * Inode flags used for atomic set/get
 436  */
 437 enum {
 438         EXT4_INODE_SECRM        = 0,    /* Secure deletion */
 439         EXT4_INODE_UNRM         = 1,    /* Undelete */
 440         EXT4_INODE_COMPR        = 2,    /* Compress file */
 441         EXT4_INODE_SYNC         = 3,    /* Synchronous updates */
 442         EXT4_INODE_IMMUTABLE    = 4,    /* Immutable file */
 443         EXT4_INODE_APPEND       = 5,    /* writes to file may only append */
 444         EXT4_INODE_NODUMP       = 6,    /* do not dump file */
 445         EXT4_INODE_NOATIME      = 7,    /* do not update atime */
 446 /* Reserved for compression usage... */
 447         EXT4_INODE_DIRTY        = 8,
 448         EXT4_INODE_COMPRBLK     = 9,    /* One or more compressed clusters */
 449         EXT4_INODE_NOCOMPR      = 10,   /* Don't compress */
 450         EXT4_INODE_ECOMPR       = 11,   /* Compression error */
 451 /* End compression flags --- maybe not all used */
 452         EXT4_INODE_INDEX        = 12,   /* hash-indexed directory */
 453         EXT4_INODE_IMAGIC       = 13,   /* AFS directory */
 454         EXT4_INODE_JOURNAL_DATA = 14,   /* file data should be journaled */
 455         EXT4_INODE_NOTAIL       = 15,   /* file tail should not be merged */
 456         EXT4_INODE_DIRSYNC      = 16,   /* dirsync behaviour (directories only) */
 457         EXT4_INODE_TOPDIR       = 17,   /* Top of directory hierarchies*/
 458         EXT4_INODE_HUGE_FILE    = 18,   /* Set to each huge file */
 459         EXT4_INODE_EXTENTS      = 19,   /* Inode uses extents */
 460         EXT4_INODE_EA_INODE     = 21,   /* Inode used for large EA */
 461         EXT4_INODE_EOFBLOCKS    = 22,   /* Blocks allocated beyond EOF */
 462         EXT4_INODE_INLINE_DATA  = 28,   /* Data in inode. */
 463         EXT4_INODE_RESERVED     = 31,   /* reserved for ext4 lib */
 464 };
 465
 466 #define TEST_FLAG_VALUE(FLAG) (EXT4_##FLAG##_FL == (1 << EXT4_INODE_##FLAG))
 467 #define CHECK_FLAG_VALUE(FLAG) if (!TEST_FLAG_VALUE(FLAG)) { \
 468         printk(KERN_EMERG "EXT4 flag fail: " #FLAG ": %d %d\n", \
 469                 EXT4_##FLAG##_FL, EXT4_INODE_##FLAG); BUG_ON(1); }
 470
 471 /*
 472  * Since it's pretty easy to mix up bit numbers and hex values, and we
 473  * can't do a compile-time test for ENUM values, we use a run-time
 474  * test to make sure that EXT4_XXX_FL is consistent with respect to
 475  * EXT4_INODE_XXX.  If all is well the printk and BUG_ON will all drop
 476  * out so it won't cost any extra space in the compiled kernel image.
 477  * But it's important that these values are the same, since we are
 478  * using EXT4_INODE_XXX to test for the flag values, but EXT4_XX_FL
 479  * must be consistent with the values of FS_XXX_FL defined in
 480  * include/linux/fs.h and the on-disk values found in ext2, ext3, and
 481  * ext4 filesystems, and of course the values defined in e2fsprogs.
 482  *
 483  * It's not paranoia if the Murphy's Law really *is* out to get you.  :-)
 484  */
 485 static inline void ext4_check_flag_values(void)
 486 {
 487         CHECK_FLAG_VALUE(SECRM);
 488         CHECK_FLAG_VALUE(UNRM);
 489         CHECK_FLAG_VALUE(COMPR);
 490         CHECK_FLAG_VALUE(SYNC);
 491         CHECK_FLAG_VALUE(IMMUTABLE);
 492         CHECK_FLAG_VALUE(APPEND);
 493         CHECK_FLAG_VALUE(NODUMP);
 494         CHECK_FLAG_VALUE(NOATIME);
 495         CHECK_FLAG_VALUE(DIRTY);
 496         CHECK_FLAG_VALUE(COMPRBLK);
 497         CHECK_FLAG_VALUE(NOCOMPR);
 498         CHECK_FLAG_VALUE(ECOMPR);
 499         CHECK_FLAG_VALUE(INDEX);
 500         CHECK_FLAG_VALUE(IMAGIC);
 501         CHECK_FLAG_VALUE(JOURNAL_DATA);
 502         CHECK_FLAG_VALUE(NOTAIL);
 503         CHECK_FLAG_VALUE(DIRSYNC);
 504         CHECK_FLAG_VALUE(TOPDIR);
 505         CHECK_FLAG_VALUE(HUGE_FILE);
 506         CHECK_FLAG_VALUE(EXTENTS);
 507         CHECK_FLAG_VALUE(EA_INODE);
 508         CHECK_FLAG_VALUE(EOFBLOCKS);
 509         CHECK_FLAG_VALUE(INLINE_DATA);
 510         CHECK_FLAG_VALUE(RESERVED);
 511 }
 512
 513 /* Used to pass group descriptor data when online resize is done */
 514 struct ext4_new_group_input {
 515         __u32 group;            /* Group number for this data */
 516         __u64 block_bitmap;     /* Absolute block number of block bitmap */
 517         __u64 inode_bitmap;     /* Absolute block number of inode bitmap */
 518         __u64 inode_table;      /* Absolute block number of inode table start */
 519         __u32 blocks_count;     /* Total number of blocks in this group */
 520         __u16 reserved_blocks;  /* Number of reserved blocks in this group */
 521         __u16 unused;
 522 };
 523
 524 #if defined(__KERNEL__) && defined(CONFIG_COMPAT)
 525 struct compat_ext4_new_group_input {
 526         u32 group;
 527         compat_u64 block_bitmap;
 528         compat_u64 inode_bitmap;
 529         compat_u64 inode_table;
 530         u32 blocks_count;
 531         u16 reserved_blocks;
 532         u16 unused;
 533 };
 534 #endif
 535
 536 /* The struct ext4_new_group_input in kernel space, with free_blocks_count */
 537 struct ext4_new_group_data {
 538         __u32 group;
 539         __u64 block_bitmap;
 540         __u64 inode_bitmap;
 541         __u64 inode_table;
 542         __u32 blocks_count;
 543         __u16 reserved_blocks;
 544         __u16 unused;
 545         __u32 free_blocks_count;
 546 };
 547
 548 /* Indexes used to index group tables in ext4_new_group_data */
 549 enum {
 550         BLOCK_BITMAP = 0,       /* block bitmap */
 551         INODE_BITMAP,           /* inode bitmap */
 552         INODE_TABLE,            /* inode tables */
 553         GROUP_TABLE_COUNT,
 554 };
 555
 556 /*
 557  * Flags used by ext4_map_blocks()
 558  */
 559         /* Allocate any needed blocks and/or convert an unitialized
 560            extent to be an initialized ext4 */
 561 #define EXT4_GET_BLOCKS_CREATE                  0x0001
 562         /* Request the creation of an unitialized extent */
 563 #define EXT4_GET_BLOCKS_UNINIT_EXT              0x0002
 564 #define EXT4_GET_BLOCKS_CREATE_UNINIT_EXT       (EXT4_GET_BLOCKS_UNINIT_EXT|\
 565                                                  EXT4_GET_BLOCKS_CREATE)
 566         /* Caller is from the delayed allocation writeout path,
 567            so set the magic i_delalloc_reserve_flag after taking the
 568            inode allocation semaphore for */
 569 #define EXT4_GET_BLOCKS_DELALLOC_RESERVE        0x0004
 570         /* caller is from the direct IO path, request to creation of an
 571         unitialized extents if not allocated, split the uninitialized
 572         extent if blocks has been preallocated already*/
 573 #define EXT4_GET_BLOCKS_PRE_IO                  0x0008
 574 #define EXT4_GET_BLOCKS_CONVERT                 0x0010
 575 #define EXT4_GET_BLOCKS_IO_CREATE_EXT           (EXT4_GET_BLOCKS_PRE_IO|\
 576                                          EXT4_GET_BLOCKS_CREATE_UNINIT_EXT)
 577         /* Convert extent to initialized after IO complete */
 578 #define EXT4_GET_BLOCKS_IO_CONVERT_EXT          (EXT4_GET_BLOCKS_CONVERT|\
 579                                          EXT4_GET_BLOCKS_CREATE_UNINIT_EXT)
 580         /* Punch out blocks of an extent */
 581 #define EXT4_GET_BLOCKS_PUNCH_OUT_EXT           0x0020
 582         /* Don't normalize allocation size (used for fallocate) */
 583 #define EXT4_GET_BLOCKS_NO_NORMALIZE            0x0040
 584         /* Request will not result in inode size update (user for fallocate) */
 585 #define EXT4_GET_BLOCKS_KEEP_SIZE               0x0080
 586         /* Do not take i_data_sem locking in ext4_map_blocks */
 587 #define EXT4_GET_BLOCKS_NO_LOCK                 0x0100
 588
 589 /*
 590  * Flags used by ext4_free_blocks
 591  */
 592 #define EXT4_FREE_BLOCKS_METADATA       0x0001
 593 #define EXT4_FREE_BLOCKS_FORGET         0x0002
 594 #define EXT4_FREE_BLOCKS_VALIDATED      0x0004
 595 #define EXT4_FREE_BLOCKS_NO_QUOT_UPDATE 0x0008
 596 #define EXT4_FREE_BLOCKS_NOFREE_FIRST_CLUSTER   0x0010
 597 #define EXT4_FREE_BLOCKS_NOFREE_LAST_CLUSTER    0x0020
 598
 599 /*
 600  * Flags used by ext4_discard_partial_page_buffers
 601  */
 602 #define EXT4_DISCARD_PARTIAL_PG_ZERO_UNMAPPED   0x0001
 603
 604 /*
 605  * ioctl commands
 606  */
 607 #define EXT4_IOC_GETFLAGS               FS_IOC_GETFLAGS
 608 #define EXT4_IOC_SETFLAGS               FS_IOC_SETFLAGS
 609 #define EXT4_IOC_GETVERSION             _IOR('f', 3, long)
 610 #define EXT4_IOC_SETVERSION             _IOW('f', 4, long)
 611 #define EXT4_IOC_GETVERSION_OLD         FS_IOC_GETVERSION
 612 #define EXT4_IOC_SETVERSION_OLD         FS_IOC_SETVERSION
 613 #define EXT4_IOC_GETRSVSZ               _IOR('f', 5, long)
 614 #define EXT4_IOC_SETRSVSZ               _IOW('f', 6, long)
 615 #define EXT4_IOC_GROUP_EXTEND           _IOW('f', 7, unsigned long)
 616 #define EXT4_IOC_GROUP_ADD              _IOW('f', 8, struct ext4_new_group_input)
 617 #define EXT4_IOC_MIGRATE                _IO('f', 9)
 618  /* note ioctl 10 reserved for an early version of the FIEMAP ioctl */
 619  /* note ioctl 11 reserved for filesystem-independent FIEMAP ioctl */
 620 #define EXT4_IOC_ALLOC_DA_BLKS          _IO('f', 12)
 621 #define EXT4_IOC_MOVE_EXT               _IOWR('f', 15, struct move_extent)
 622 #define EXT4_IOC_RESIZE_FS              _IOW('f', 16, __u64)
 623
 624 #if defined(__KERNEL__) && defined(CONFIG_COMPAT)
 625 /*
 626  * ioctl commands in 32 bit emulation
 627  */
 628 #define EXT4_IOC32_GETFLAGS             FS_IOC32_GETFLAGS
 629 #define EXT4_IOC32_SETFLAGS             FS_IOC32_SETFLAGS
 630 #define EXT4_IOC32_GETVERSION           _IOR('f', 3, int)
 631 #define EXT4_IOC32_SETVERSION           _IOW('f', 4, int)
 632 #define EXT4_IOC32_GETRSVSZ             _IOR('f', 5, int)
 633 #define EXT4_IOC32_SETRSVSZ             _IOW('f', 6, int)
 634 #define EXT4_IOC32_GROUP_EXTEND         _IOW('f', 7, unsigned int)
 635 #define EXT4_IOC32_GROUP_ADD            _IOW('f', 8, struct compat_ext4_new_group_input)
 636 #define EXT4_IOC32_GETVERSION_OLD       FS_IOC32_GETVERSION
 637 #define EXT4_IOC32_SETVERSION_OLD       FS_IOC32_SETVERSION
 638 #endif
 639
 640 /* Max physical block we can address w/o extents */
 641 #define EXT4_MAX_BLOCK_FILE_PHYS        0xFFFFFFFF
 642
 643 /*
 644  * Structure of an inode on the disk
 645  */
 646 struct ext4_inode {
 647         __le16  i_mode;         /* File mode */
 648         __le16  i_uid;          /* Low 16 bits of Owner Uid */
 649         __le32  i_size_lo;      /* Size in bytes */
 650         __le32  i_atime;        /* Access time */
 651         __le32  i_ctime;        /* Inode Change time */
 652         __le32  i_mtime;        /* Modification time */
 653         __le32  i_dtime;        /* Deletion Time */
 654         __le16  i_gid;          /* Low 16 bits of Group Id */
 655         __le16  i_links_count;  /* Links count */
 656         __le32  i_blocks_lo;    /* Blocks count */
 657         __le32  i_flags;        /* File flags */
 658         union {
 659                 struct {
 660                         __le32  l_i_version;
 661                 } linux1;
 662                 struct {
 663                         __u32  h_i_translator;
 664                 } hurd1;
 665                 struct {
 666                         __u32  m_i_reserved1;
 667                 } masix1;
 668         } osd1;                         /* OS dependent 1 */
 669         __le32  i_block[EXT4_N_BLOCKS];/* Pointers to blocks */
 670         __le32  i_generation;   /* File version (for NFS) */
 671         __le32  i_file_acl_lo;  /* File ACL */
 672         __le32  i_size_high;
 673         __le32  i_obso_faddr;   /* Obsoleted fragment address */
 674         union {
 675                 struct {
 676                         __le16  l_i_blocks_high; /* were l_i_reserved1 */
 677                         __le16  l_i_file_acl_high;
 678                         __le16  l_i_uid_high;   /* these 2 fields */
 679                         __le16  l_i_gid_high;   /* were reserved2[0] */
 680                         __le16  l_i_checksum_lo;/* crc32c(uuid+inum+inode) LE */
 681                         __le16  l_i_reserved;
 682                 } linux2;
 683                 struct {
 684                         __le16  h_i_reserved1;  /* Obsoleted fragment number/size which are removed in ext4 */
 685                         __u16   h_i_mode_high;
 686                         __u16   h_i_uid_high;
 687                         __u16   h_i_gid_high;
 688                         __u32   h_i_author;
 689                 } hurd2;
 690                 struct {
 691                         __le16  h_i_reserved1;  /* Obsoleted fragment number/size which are removed in ext4 */
 692                         __le16  m_i_file_acl_high;
 693                         __u32   m_i_reserved2[2];
 694                 } masix2;
 695         } osd2;                         /* OS dependent 2 */
 696         __le16  i_extra_isize;
 697         __le16  i_checksum_hi;  /* crc32c(uuid+inum+inode) BE */
 698         __le32  i_ctime_extra;  /* extra Change time      (nsec << 2 | epoch) */
 699         __le32  i_mtime_extra;  /* extra Modification time(nsec << 2 | epoch) */
 700         __le32  i_atime_extra;  /* extra Access time      (nsec << 2 | epoch) */
 701         __le32  i_crtime;       /* File Creation time */
 702         __le32  i_crtime_extra; /* extra FileCreationtime (nsec << 2 | epoch) */
 703         __le32  i_version_hi;   /* high 32 bits for 64-bit version */
 704 };
 705
 706 struct move_extent {
 707         __u32 reserved;         /* should be zero */
 708         __u32 donor_fd;         /* donor file descriptor */
 709         __u64 orig_start;       /* logical start offset in block for orig */
 710         __u64 donor_start;      /* logical start offset in block for donor */
 711         __u64 len;              /* block length to be moved */
 712         __u64 moved_len;        /* moved block length */
 713 };
 714
 715 #define EXT4_EPOCH_BITS 2
 716 #define EXT4_EPOCH_MASK ((1 << EXT4_EPOCH_BITS) - 1)
 717 #define EXT4_NSEC_MASK  (~0UL << EXT4_EPOCH_BITS)
 718
 719 /*
 720  * Extended fields will fit into an inode if the filesystem was formatted
 721  * with large inodes (-I 256 or larger) and there are not currently any EAs
 722  * consuming all of the available space. For new inodes we always reserve
 723  * enough space for the kernel's known extended fields, but for inodes
 724  * created with an old kernel this might not have been the case. None of
 725  * the extended inode fields is critical for correct filesystem operation.
 726  * This macro checks if a certain field fits in the inode. Note that
 727  * inode-size = GOOD_OLD_INODE_SIZE + i_extra_isize
 728  */
 729 #define EXT4_FITS_IN_INODE(ext4_inode, einode, field)   \
 730         ((offsetof(typeof(*ext4_inode), field) +        \
 731           sizeof((ext4_inode)->field))                  \
 732         <= (EXT4_GOOD_OLD_INODE_SIZE +                  \
 733             (einode)->i_extra_isize))                   \
 734
 735 static inline __le32 ext4_encode_extra_time(struct timespec *time)
 736 {
 737        return cpu_to_le32((sizeof(time->tv_sec) > 4 ?
 738                            (time->tv_sec >> 32) & EXT4_EPOCH_MASK : 0) |
 739                           ((time->tv_nsec << EXT4_EPOCH_BITS) & EXT4_NSEC_MASK));
 740 }
 741
 742 static inline void ext4_decode_extra_time(struct timespec *time, __le32 extra)
 743 {
 744        if (sizeof(time->tv_sec) > 4)
 745                time->tv_sec |= (__u64)(le32_to_cpu(extra) & EXT4_EPOCH_MASK)
 746                                << 32;
 747        time->tv_nsec = (le32_to_cpu(extra) & EXT4_NSEC_MASK) >> EXT4_EPOCH_BITS;
 748 }
 749
 750 #define EXT4_INODE_SET_XTIME(xtime, inode, raw_inode)                          \
 751 do {                                                                           \
 752         (raw_inode)->xtime = cpu_to_le32((inode)->xtime.tv_sec);               \
 753         if (EXT4_FITS_IN_INODE(raw_inode, EXT4_I(inode), xtime ## _extra))     \
 754                 (raw_inode)->xtime ## _extra =                                 \
 755                                 ext4_encode_extra_time(&(inode)->xtime);       \
 756 } while (0)
 757
 758 #define EXT4_EINODE_SET_XTIME(xtime, einode, raw_inode)                        \
 759 do {                                                                           \
 760         if (EXT4_FITS_IN_INODE(raw_inode, einode, xtime))                      \
 761                 (raw_inode)->xtime = cpu_to_le32((einode)->xtime.tv_sec);      \
 762         if (EXT4_FITS_IN_INODE(raw_inode, einode, xtime ## _extra))            \
 763                 (raw_inode)->xtime ## _extra =                                 \
 764                                 ext4_encode_extra_time(&(einode)->xtime);      \
 765 } while (0)
 766
 767 #define EXT4_INODE_GET_XTIME(xtime, inode, raw_inode)                          \
 768 do {                                                                           \
 769         (inode)->xtime.tv_sec = (signed)le32_to_cpu((raw_inode)->xtime);       \
 770         if (EXT4_FITS_IN_INODE(raw_inode, EXT4_I(inode), xtime ## _extra))     \
 771                 ext4_decode_extra_time(&(inode)->xtime,                        \
 772                                        raw_inode->xtime ## _extra);            \
 773         else                                                                   \
 774                 (inode)->xtime.tv_nsec = 0;                                    \
 775 } while (0)
 776
 777 #define EXT4_EINODE_GET_XTIME(xtime, einode, raw_inode)                        \
 778 do {                                                                           \
 779         if (EXT4_FITS_IN_INODE(raw_inode, einode, xtime))                      \
 780                 (einode)->xtime.tv_sec =                                       \
 781                         (signed)le32_to_cpu((raw_inode)->xtime);               \
 782         if (EXT4_FITS_IN_INODE(raw_inode, einode, xtime ## _extra))            \
 783                 ext4_decode_extra_time(&(einode)->xtime,                       \
 784                                        raw_inode->xtime ## _extra);            \
 785         else                                                                   \
 786                 (einode)->xtime.tv_nsec = 0;                                   \
 787 } while (0)
 788
 789 #define i_disk_version osd1.linux1.l_i_version
 790
 791 #if defined(__KERNEL__) || defined(__linux__)
 792 #define i_reserved1     osd1.linux1.l_i_reserved1
 793 #define i_file_acl_high osd2.linux2.l_i_file_acl_high
 794 #define i_blocks_high   osd2.linux2.l_i_blocks_high
 795 #define i_uid_low       i_uid
 796 #define i_gid_low       i_gid
 797 #define i_uid_high      osd2.linux2.l_i_uid_high
 798 #define i_gid_high      osd2.linux2.l_i_gid_high
 799 #define i_checksum_lo   osd2.linux2.l_i_checksum_lo
 800
 801 #elif defined(__GNU__)
 802
 803 #define i_translator    osd1.hurd1.h_i_translator
 804 #define i_uid_high      osd2.hurd2.h_i_uid_high
 805 #define i_gid_high      osd2.hurd2.h_i_gid_high
 806 #define i_author        osd2.hurd2.h_i_author
 807
 808 #elif defined(__masix__)
 809
 810 #define i_reserved1     osd1.masix1.m_i_reserved1
 811 #define i_file_acl_high osd2.masix2.m_i_file_acl_high
 812 #define i_reserved2     osd2.masix2.m_i_reserved2
 813
 814 #endif /* defined(__KERNEL__) || defined(__linux__) */
 815
 816 /*
 817  * storage for cached extent
 818  * If ec_len == 0, then the cache is invalid.
 819  * If ec_start == 0, then the cache represents a gap (null mapping)
 820  */
 821 struct ext4_ext_cache {
 822         ext4_fsblk_t    ec_start;
 823         ext4_lblk_t     ec_block;
 824         __u32           ec_len; /* must be 32bit to return holes */
 825 };
 826
 827 #include "extents_status.h"
 828
 829 /*
 830  * fourth extended file system inode data in memory
 831  */
 832 struct ext4_inode_info {
 833         __le32  i_data[15];     /* unconverted */
 834         __u32   i_dtime;
 835         ext4_fsblk_t    i_file_acl;
 836
 837         /*
 838          * i_block_group is the number of the block group which contains
 839          * this file's inode.  Constant across the lifetime of the inode,
 840          * it is ued for making block allocation decisions - we try to
 841          * place a file's data blocks near its inode block, and new inodes
 842          * near to their parent directory's inode.
 843          */
 844         ext4_group_t    i_block_group;
 845         ext4_lblk_t     i_dir_start_lookup;
 846 #if (BITS_PER_LONG < 64)
 847         unsigned long   i_state_flags;          /* Dynamic state flags */
 848 #endif
 849         unsigned long   i_flags;
 850
 851 #ifdef CONFIG_EXT4_FS_XATTR
 852         /*
 853          * Extended attributes can be read independently of the main file
 854          * data. Taking i_mutex even when reading would cause contention
 855          * between readers of EAs and writers of regular file data, so
 856          * instead we synchronize on xattr_sem when reading or changing
 857          * EAs.
 858          */
 859         struct rw_semaphore xattr_sem;
 860 #endif
 861
 862         struct list_head i_orphan;      /* unlinked but open inodes */
 863
 864         /*
 865          * i_disksize keeps track of what the inode size is ON DISK, not
 866          * in memory.  During truncate, i_size is set to the new size by
 867          * the VFS prior to calling ext4_truncate(), but the filesystem won't
 868          * set i_disksize to 0 until the truncate is actually under way.
 869          *
 870          * The intent is that i_disksize always represents the blocks which
 871          * are used by this file.  This allows recovery to restart truncate
 872          * on orphans if we crash during truncate.  We actually write i_disksize
 873          * into the on-disk inode when writing inodes out, instead of i_size.
 874          *
 875          * The only time when i_disksize and i_size may be different is when
 876          * a truncate is in progress.  The only things which change i_disksize
 877          * are ext4_get_block (growth) and ext4_truncate (shrinkth).
 878          */
 879         loff_t  i_disksize;
 880
 881         /*
 882          * i_data_sem is for serialising ext4_truncate() against
 883          * ext4_getblock().  In the 2.4 ext2 design, great chunks of inode's
 884          * data tree are chopped off during truncate. We can't do that in
 885          * ext4 because whenever we perform intermediate commits during
 886          * truncate, the inode and all the metadata blocks *must* be in a
 887          * consistent state which allows truncation of the orphans to restart
 888          * during recovery.  Hence we must fix the get_block-vs-truncate race
 889          * by other means, so we have i_data_sem.
 890          */
 891         struct rw_semaphore i_data_sem;
 892         struct inode vfs_inode;
 893         struct jbd2_inode *jinode;
 894
 895         struct ext4_ext_cache i_cached_extent;
 896         /*
 897          * File creation time. Its function is same as that of
 898          * struct timespec i_{a,c,m}time in the generic inode.
 899          */
 900         struct timespec i_crtime;
 901
 902         /* mballoc */
 903         struct list_head i_prealloc_list;
 904         spinlock_t i_prealloc_lock;
 905
 906         /* extents status tree */
 907         struct ext4_es_tree i_es_tree;
 908         rwlock_t i_es_lock;
 909
 910         /* ialloc */
 911         ext4_group_t    i_last_alloc_group;
 912
 913         /* allocation reservation info for delalloc */
 914         /* In case of bigalloc, these refer to clusters rather than blocks */
 915         unsigned int i_reserved_data_blocks;
 916         unsigned int i_reserved_meta_blocks;
 917         unsigned int i_allocated_meta_blocks;
 918         ext4_lblk_t i_da_metadata_calc_last_lblock;
 919         int i_da_metadata_calc_len;
 920
 921         /* on-disk additional length */
 922         __u16 i_extra_isize;
 923
 924         /* Indicate the inline data space. */
 925         u16 i_inline_off;
 926         u16 i_inline_size;
 927
 928 #ifdef CONFIG_QUOTA
 929         /* quota space reservation, managed internally by quota code */
 930         qsize_t i_reserved_quota;
 931 #endif
 932
 933         /* completed IOs that might need unwritten extents handling */
 934         struct list_head i_completed_io_list;
 935         spinlock_t i_completed_io_lock;
 936         atomic_t i_ioend_count; /* Number of outstanding io_end structs */
 937         atomic_t i_unwritten; /* Nr. of inflight conversions pending */
 938
 939         spinlock_t i_block_reservation_lock;
 940
 941         /*
 942          * Transactions that contain inode's metadata needed to complete
 943          * fsync and fdatasync, respectively.
 944          */
 945         tid_t i_sync_tid;
 946         tid_t i_datasync_tid;
 947
 948         /* Precomputed uuid+inum+igen checksum for seeding inode checksums */
 949         __u32 i_csum_seed;
 950 };
 951
 952 /*
 953  * File system states
 954  */
 955 #define EXT4_VALID_FS                   0x0001  /* Unmounted cleanly */
 956 #define EXT4_ERROR_FS                   0x0002  /* Errors detected */
 957 #define EXT4_ORPHAN_FS                  0x0004  /* Orphans being recovered */
 958
 959 /*
 960  * Misc. filesystem flags
 961  */
 962 #define EXT2_FLAGS_SIGNED_HASH          0x0001  /* Signed dirhash in use */
 963 #define EXT2_FLAGS_UNSIGNED_HASH        0x0002  /* Unsigned dirhash in use */
 964 #define EXT2_FLAGS_TEST_FILESYS         0x0004  /* to test development code */
 965
 966 /*
 967  * Mount flags
 968  */
 969 #define EXT4_MOUNT_GRPID                0x00004 /* Create files with directory's group */
 970 #define EXT4_MOUNT_DEBUG                0x00008 /* Some debugging messages */
 971 #define EXT4_MOUNT_ERRORS_CONT          0x00010 /* Continue on errors */
 972 #define EXT4_MOUNT_ERRORS_RO            0x00020 /* Remount fs ro on errors */
 973 #define EXT4_MOUNT_ERRORS_PANIC         0x00040 /* Panic on errors */
 974 #define EXT4_MOUNT_ERRORS_MASK          0x00070
 975 #define EXT4_MOUNT_MINIX_DF             0x00080 /* Mimics the Minix statfs */
 976 #define EXT4_MOUNT_NOLOAD               0x00100 /* Don't use existing journal*/
 977 #define EXT4_MOUNT_DATA_FLAGS           0x00C00 /* Mode for data writes: */
 978 #define EXT4_MOUNT_JOURNAL_DATA         0x00400 /* Write data to journal */
 979 #define EXT4_MOUNT_ORDERED_DATA         0x00800 /* Flush data before commit */
 980 #define EXT4_MOUNT_WRITEBACK_DATA       0x00C00 /* No data ordering */
 981 #define EXT4_MOUNT_UPDATE_JOURNAL       0x01000 /* Update the journal format */
 982 #define EXT4_MOUNT_NO_UID32             0x02000  /* Disable 32-bit UIDs */
 983 #define EXT4_MOUNT_XATTR_USER           0x04000 /* Extended user attributes */
 984 #define EXT4_MOUNT_POSIX_ACL            0x08000 /* POSIX Access Control Lists */
 985 #define EXT4_MOUNT_NO_AUTO_DA_ALLOC     0x10000 /* No auto delalloc mapping */
 986 #define EXT4_MOUNT_BARRIER              0x20000 /* Use block barriers */
 987 #define EXT4_MOUNT_QUOTA                0x80000 /* Some quota option set */
 988 #define EXT4_MOUNT_USRQUOTA             0x100000 /* "old" user quota */
 989 #define EXT4_MOUNT_GRPQUOTA             0x200000 /* "old" group quota */
 990 #define EXT4_MOUNT_DIOREAD_NOLOCK       0x400000 /* Enable support for dio read nolocking */
 991 #define EXT4_MOUNT_JOURNAL_CHECKSUM     0x800000 /* Journal checksums */
 992 #define EXT4_MOUNT_JOURNAL_ASYNC_COMMIT 0x1000000 /* Journal Async Commit */
 993 #define EXT4_MOUNT_MBLK_IO_SUBMIT       0x4000000 /* multi-block io submits */
 994 #define EXT4_MOUNT_DELALLOC             0x8000000 /* Delalloc support */
 995 #define EXT4_MOUNT_DATA_ERR_ABORT       0x10000000 /* Abort on file data write */
 996 #define EXT4_MOUNT_BLOCK_VALIDITY       0x20000000 /* Block validity checking */
 997 #define EXT4_MOUNT_DISCARD              0x40000000 /* Issue DISCARD requests */
 998 #define EXT4_MOUNT_INIT_INODE_TABLE     0x80000000 /* Initialize uninitialized itables */
 999
1000 #define EXT4_MOUNT2_EXPLICIT_DELALLOC   0x00000001 /* User explicitly
1001                                                       specified delalloc */
1002
1003 #define clear_opt(sb, opt)              EXT4_SB(sb)->s_mount_opt &= \
1004                                                 ~EXT4_MOUNT_##opt
1005 #define set_opt(sb, opt)                EXT4_SB(sb)->s_mount_opt |= \
1006                                                 EXT4_MOUNT_##opt
1007 #define test_opt(sb, opt)               (EXT4_SB(sb)->s_mount_opt & \
1008                                          EXT4_MOUNT_##opt)
1009
1010 #define clear_opt2(sb, opt)             EXT4_SB(sb)->s_mount_opt2 &= \
1011                                                 ~EXT4_MOUNT2_##opt
1012 #define set_opt2(sb, opt)               EXT4_SB(sb)->s_mount_opt2 |= \
1013                                                 EXT4_MOUNT2_##opt
1014 #define test_opt2(sb, opt)              (EXT4_SB(sb)->s_mount_opt2 & \
1015                                          EXT4_MOUNT2_##opt)
1016
1017 #define ext4_test_and_set_bit           __test_and_set_bit_le
1018 #define ext4_set_bit                    __set_bit_le
1019 #define ext4_set_bit_atomic             ext2_set_bit_atomic
1020 #define ext4_test_and_clear_bit         __test_and_clear_bit_le
1021 #define ext4_clear_bit                  __clear_bit_le
1022 #define ext4_clear_bit_atomic           ext2_clear_bit_atomic
1023 #define ext4_test_bit                   test_bit_le
1024 #define ext4_find_next_zero_bit         find_next_zero_bit_le
1025 #define ext4_find_next_bit              find_next_bit_le
1026
1027 extern void ext4_set_bits(void *bm, int cur, int len);
1028
1029 /*
1030  * Maximal mount counts between two filesystem checks
1031  */
1032 #define EXT4_DFL_MAX_MNT_COUNT          20      /* Allow 20 mounts */
1033 #define EXT4_DFL_CHECKINTERVAL          0       /* Don't use interval check */
1034
1035 /*
1036  * Behaviour when detecting errors
1037  */
1038 #define EXT4_ERRORS_CONTINUE            1       /* Continue execution */
1039 #define EXT4_ERRORS_RO                  2       /* Remount fs read-only */
1040 #define EXT4_ERRORS_PANIC               3       /* Panic */
1041 #define EXT4_ERRORS_DEFAULT             EXT4_ERRORS_CONTINUE
1042
1043 /* Metadata checksum algorithm codes */
1044 #define EXT4_CRC32C_CHKSUM              1
1045
1046 /*
1047  * Structure of the super block
1048  */
1049 struct ext4_super_block {
1050 /*00*/  __le32  s_inodes_count;         /* Inodes count */
1051         __le32  s_blocks_count_lo;      /* Blocks count */
1052         __le32  s_r_blocks_count_lo;    /* Reserved blocks count */
1053         __le32  s_free_blocks_count_lo; /* Free blocks count */
1054 /*10*/  __le32  s_free_inodes_count;    /* Free inodes count */
1055         __le32  s_first_data_block;     /* First Data Block */
1056         __le32  s_log_block_size;       /* Block size */
1057         __le32  s_log_cluster_size;     /* Allocation cluster size */
1058 /*20*/  __le32  s_blocks_per_group;     /* # Blocks per group */
1059         __le32  s_clusters_per_group;   /* # Clusters per group */
1060         __le32  s_inodes_per_group;     /* # Inodes per group */
1061         __le32  s_mtime;                /* Mount time */
1062 /*30*/  __le32  s_wtime;                /* Write time */
1063         __le16  s_mnt_count;            /* Mount count */
1064         __le16  s_max_mnt_count;        /* Maximal mount count */
1065         __le16  s_magic;                /* Magic signature */
1066         __le16  s_state;                /* File system state */
1067         __le16  s_errors;               /* Behaviour when detecting errors */
1068         __le16  s_minor_rev_level;      /* minor revision level */
1069 /*40*/  __le32  s_lastcheck;            /* time of last check */
1070         __le32  s_checkinterval;        /* max. time between checks */
1071         __le32  s_creator_os;           /* OS */
1072         __le32  s_rev_level;            /* Revision level */
1073 /*50*/  __le16  s_def_resuid;           /* Default uid for reserved blocks */
1074         __le16  s_def_resgid;           /* Default gid for reserved blocks */
1075         /*
1076          * These fields are for EXT4_DYNAMIC_REV superblocks only.
1077          *
1078          * Note: the difference between the compatible feature set and
1079          * the incompatible feature set is that if there is a bit set
1080          * in the incompatible feature set that the kernel doesn't
1081          * know about, it should refuse to mount the filesystem.
1082          *
1083          * e2fsck's requirements are more strict; if it doesn't know
1084          * about a feature in either the compatible or incompatible
1085          * feature set, it must abort and not try to meddle with
1086          * things it doesn't understand...
1087          */
1088         __le32  s_first_ino;            /* First non-reserved inode */
1089         __le16  s_inode_size;           /* size of inode structure */
1090         __le16  s_block_group_nr;       /* block group # of this superblock */
1091         __le32  s_feature_compat;       /* compatible feature set */
1092 /*60*/  __le32  s_feature_incompat;     /* incompatible feature set */
1093         __le32  s_feature_ro_compat;    /* readonly-compatible feature set */
1094 /*68*/  __u8    s_uuid[16];             /* 128-bit uuid for volume */
1095 /*78*/  char    s_volume_name[16];      /* volume name */
1096 /*88*/  char    s_last_mounted[64];     /* directory where last mounted */
1097 /*C8*/  __le32  s_algorithm_usage_bitmap; /* For compression */
1098         /*
1099          * Performance hints.  Directory preallocation should only
1100          * happen if the EXT4_FEATURE_COMPAT_DIR_PREALLOC flag is on.
1101          */
1102         __u8    s_prealloc_blocks;      /* Nr of blocks to try to preallocate*/
1103         __u8    s_prealloc_dir_blocks;  /* Nr to preallocate for dirs */
1104         __le16  s_reserved_gdt_blocks;  /* Per group desc for online growth */
1105         /*
1106          * Journaling support valid if EXT4_FEATURE_COMPAT_HAS_JOURNAL set.
1107          */
1108 /*D0*/  __u8    s_journal_uuid[16];     /* uuid of journal superblock */
1109 /*E0*/  __le32  s_journal_inum;         /* inode number of journal file */
1110         __le32  s_journal_dev;          /* device number of journal file */
1111         __le32  s_last_orphan;          /* start of list of inodes to delete */
1112         __le32  s_hash_seed[4];         /* HTREE hash seed */
1113         __u8    s_def_hash_version;     /* Default hash version to use */
1114         __u8    s_jnl_backup_type;
1115         __le16  s_desc_size;            /* size of group descriptor */
1116 /*100*/ __le32  s_default_mount_opts;
1117         __le32  s_first_meta_bg;        /* First metablock block group */
1118         __le32  s_mkfs_time;            /* When the filesystem was created */
1119         __le32  s_jnl_blocks[17];       /* Backup of the journal inode */
1120         /* 64bit support valid if EXT4_FEATURE_COMPAT_64BIT */
1121 /*150*/ __le32  s_blocks_count_hi;      /* Blocks count */
1122         __le32  s_r_blocks_count_hi;    /* Reserved blocks count */
1123         __le32  s_free_blocks_count_hi; /* Free blocks count */
1124         __le16  s_min_extra_isize;      /* All inodes have at least # bytes */
1125         __le16  s_want_extra_isize;     /* New inodes should reserve # bytes */
1126         __le32  s_flags;                /* Miscellaneous flags */
1127         __le16  s_raid_stride;          /* RAID stride */
1128         __le16  s_mmp_update_interval;  /* # seconds to wait in MMP checking */
1129         __le64  s_mmp_block;            /* Block for multi-mount protection */
1130         __le32  s_raid_stripe_width;    /* blocks on all data disks (N*stride)*/
1131         __u8    s_log_groups_per_flex;  /* FLEX_BG group size */
1132         __u8    s_checksum_type;        /* metadata checksum algorithm used */
1133         __le16  s_reserved_pad;
1134         __le64  s_kbytes_written;       /* nr of lifetime kilobytes written */
1135         __le32  s_snapshot_inum;        /* Inode number of active snapshot */
1136         __le32  s_snapshot_id;          /* sequential ID of active snapshot */
1137         __le64  s_snapshot_r_blocks_count; /* reserved blocks for active
1138                                               snapshot's future use */
1139         __le32  s_snapshot_list;        /* inode number of the head of the
1140                                            on-disk snapshot list */
1141 #define EXT4_S_ERR_START offsetof(struct ext4_super_block, s_error_count)
1142         __le32  s_error_count;          /* number of fs errors */
1143         __le32  s_first_error_time;     /* first time an error happened */
1144         __le32  s_first_error_ino;      /* inode involved in first error */
1145         __le64  s_first_error_block;    /* block involved of first error */
1146         __u8    s_first_error_func[32]; /* function where the error happened */
1147         __le32  s_first_error_line;     /* line number where error happened */
1148         __le32  s_last_error_time;      /* most recent time of an error */
1149         __le32  s_last_error_ino;       /* inode involved in last error */
1150         __le32  s_last_error_line;      /* line number where error happened */
1151         __le64  s_last_error_block;     /* block involved of last error */
1152         __u8    s_last_error_func[32];  /* function where the error happened */
1153 #define EXT4_S_ERR_END offsetof(struct ext4_super_block, s_mount_opts)
1154         __u8    s_mount_opts[64];
1155         __le32  s_usr_quota_inum;       /* inode for tracking user quota */
1156         __le32  s_grp_quota_inum;       /* inode for tracking group quota */
1157         __le32  s_overhead_clusters;    /* overhead blocks/clusters in fs */
1158         __le32  s_reserved[108];        /* Padding to the end of the block */
1159         __le32  s_checksum;             /* crc32c(superblock) */
1160 };
1161
1162 #define EXT4_S_ERR_LEN (EXT4_S_ERR_END - EXT4_S_ERR_START)
1163
1164 #ifdef __KERNEL__
1165
1166 /*
1167  * run-time mount flags
1168  */
1169 #define EXT4_MF_MNTDIR_SAMPLED  0x0001
1170 #define EXT4_MF_FS_ABORTED      0x0002  /* Fatal error detected */
1171
1172 /*
1173  * fourth extended-fs super-block data in memory
1174  */
1175 struct ext4_sb_info {
1176         unsigned long s_desc_size;      /* Size of a group descriptor in bytes */
1177         unsigned long s_inodes_per_block;/* Number of inodes per block */
1178         unsigned long s_blocks_per_group;/* Number of blocks in a group */
1179         unsigned long s_clusters_per_group; /* Number of clusters in a group */
1180         unsigned long s_inodes_per_group;/* Number of inodes in a group */
1181         unsigned long s_itb_per_group;  /* Number of inode table blocks per group */
1182         unsigned long s_gdb_count;      /* Number of group descriptor blocks */
1183         unsigned long s_desc_per_block; /* Number of group descriptors per block */
1184         ext4_group_t s_groups_count;    /* Number of groups in the fs */
1185         ext4_group_t s_blockfile_groups;/* Groups acceptable for non-extent files */
1186         unsigned long s_overhead;  /* # of fs overhead clusters */
1187         unsigned int s_cluster_ratio;   /* Number of blocks per cluster */
1188         unsigned int s_cluster_bits;    /* log2 of s_cluster_ratio */
1189         loff_t s_bitmap_maxbytes;       /* max bytes for bitmap files */
1190         struct buffer_head * s_sbh;     /* Buffer containing the super block */
1191         struct ext4_super_block *s_es;  /* Pointer to the super block in the buffer */
1192         struct buffer_head **s_group_desc;
1193         unsigned int s_mount_opt;
1194         unsigned int s_mount_opt2;
1195         unsigned int s_mount_flags;
1196         unsigned int s_def_mount_opt;
1197         ext4_fsblk_t s_sb_block;
1198         kuid_t s_resuid;
1199         kgid_t s_resgid;
1200         unsigned short s_mount_state;
1201         unsigned short s_pad;
1202         int s_addr_per_block_bits;
1203         int s_desc_per_block_bits;
1204         int s_inode_size;
1205         int s_first_ino;
1206         unsigned int s_inode_readahead_blks;
1207         unsigned int s_inode_goal;
1208         spinlock_t s_next_gen_lock;
1209         u32 s_next_generation;
1210         u32 s_hash_seed[4];
1211         int s_def_hash_version;
1212         int s_hash_unsigned;    /* 3 if hash should be signed, 0 if not */
1213         struct percpu_counter s_freeclusters_counter;
1214         struct percpu_counter s_freeinodes_counter;
1215         struct percpu_counter s_dirs_counter;
1216         struct percpu_counter s_dirtyclusters_counter;
1217         struct blockgroup_lock *s_blockgroup_lock;
1218         struct proc_dir_entry *s_proc;
1219         struct kobject s_kobj;
1220         struct completion s_kobj_unregister;
1221         struct super_block *s_sb;
1222
1223         /* Journaling */
1224         struct journal_s *s_journal;
1225         struct list_head s_orphan;
1226         struct mutex s_orphan_lock;
1227         unsigned long s_resize_flags;           /* Flags indicating if there
1228                                                    is a resizer */
1229         unsigned long s_commit_interval;
1230         u32 s_max_batch_time;
1231         u32 s_min_batch_time;
1232         struct block_device *journal_bdev;
1233 #ifdef CONFIG_QUOTA
1234         char *s_qf_names[MAXQUOTAS];            /* Names of quota files with journalled quota */
1235         int s_jquota_fmt;                       /* Format of quota to use */
1236 #endif
1237         unsigned int s_want_extra_isize; /* New inodes should reserve # bytes */
1238         struct rb_root system_blks;
1239
1240 #ifdef EXTENTS_STATS
1241         /* ext4 extents stats */
1242         unsigned long s_ext_min;
1243         unsigned long s_ext_max;
1244         unsigned long s_depth_max;
1245         spinlock_t s_ext_stats_lock;
1246         unsigned long s_ext_blocks;
1247         unsigned long s_ext_extents;
1248 #endif
1249
1250         /* for buddy allocator */
1251         struct ext4_group_info ***s_group_info;
1252         struct inode *s_buddy_cache;
1253         spinlock_t s_md_lock;
1254         unsigned short *s_mb_offsets;
1255         unsigned int *s_mb_maxs;
1256         unsigned int s_group_info_size;
1257
1258         /* tunables */
1259         unsigned long s_stripe;
1260         unsigned int s_mb_stream_request;
1261         unsigned int s_mb_max_to_scan;
1262         unsigned int s_mb_min_to_scan;
1263         unsigned int s_mb_stats;
1264         unsigned int s_mb_order2_reqs;
1265         unsigned int s_mb_group_prealloc;
1266         unsigned int s_max_writeback_mb_bump;
1267         unsigned int s_max_dir_size_kb;
1268         /* where last allocation was done - for stream allocation */
1269         unsigned long s_mb_last_group;
1270         unsigned long s_mb_last_start;
1271
1272         /* stats for buddy allocator */
1273         atomic_t s_bal_reqs;    /* number of reqs with len > 1 */
1274         atomic_t s_bal_success; /* we found long enough chunks */
1275         atomic_t s_bal_allocated;       /* in blocks */
1276         atomic_t s_bal_ex_scanned;      /* total extents scanned */
1277         atomic_t s_bal_goals;   /* goal hits */
1278         atomic_t s_bal_breaks;  /* too long searches */
1279         atomic_t s_bal_2orders; /* 2^order hits */
1280         spinlock_t s_bal_lock;
1281         unsigned long s_mb_buddies_generated;
1282         unsigned long long s_mb_generation_time;
1283         atomic_t s_mb_lost_chunks;
1284         atomic_t s_mb_preallocated;
1285         atomic_t s_mb_discarded;
1286         atomic_t s_lock_busy;
1287
1288         /* locality groups */
1289         struct ext4_locality_group __percpu *s_locality_groups;
1290
1291         /* for write statistics */
1292         unsigned long s_sectors_written_start;
1293         u64 s_kbytes_written;
1294
1295         /* the size of zero-out chunk */
1296         unsigned int s_extent_max_zeroout_kb;
1297
1298         unsigned int s_log_groups_per_flex;
1299         struct flex_groups *s_flex_groups;
1300         ext4_group_t s_flex_groups_allocated;
1301
1302         /* workqueue for dio unwritten */
1303         struct workqueue_struct *dio_unwritten_wq;
1304
1305         /* timer for periodic error stats printing */
1306         struct timer_list s_err_report;
1307
1308         /* Lazy inode table initialization info */
1309         struct ext4_li_request *s_li_request;
1310         /* Wait multiplier for lazy initialization thread */
1311         unsigned int s_li_wait_mult;
1312
1313         /* Kernel thread for multiple mount protection */
1314         struct task_struct *s_mmp_tsk;
1315
1316         /* record the last minlen when FITRIM is called. */
1317         atomic_t s_last_trim_minblks;
1318
1319         /* Reference to checksum algorithm driver via cryptoapi */
1320         struct crypto_shash *s_chksum_driver;
1321
1322         /* Precomputed FS UUID checksum for seeding other checksums */
1323         __u32 s_csum_seed;
1324 };
1325
1326 static inline struct ext4_sb_info *EXT4_SB(struct super_block *sb)
1327 {
1328         return sb->s_fs_info;
1329 }
1330 static inline struct ext4_inode_info *EXT4_I(struct inode *inode)
1331 {
1332         return container_of(inode, struct ext4_inode_info, vfs_inode);
1333 }
1334
1335 static inline struct timespec ext4_current_time(struct inode *inode)
1336 {
1337         return (inode->i_sb->s_time_gran < NSEC_PER_SEC) ?
1338                 current_fs_time(inode->i_sb) : CURRENT_TIME_SEC;
1339 }
1340
1341 static inline int ext4_valid_inum(struct super_block *sb, unsigned long ino)
1342 {
1343         return ino == EXT4_ROOT_INO ||
1344                 ino == EXT4_USR_QUOTA_INO ||
1345                 ino == EXT4_GRP_QUOTA_INO ||
1346                 ino == EXT4_JOURNAL_INO ||
1347                 ino == EXT4_RESIZE_INO ||
1348                 (ino >= EXT4_FIRST_INO(sb) &&
1349                  ino <= le32_to_cpu(EXT4_SB(sb)->s_es->s_inodes_count));
1350 }
1351
1352 static inline void ext4_set_io_unwritten_flag(struct inode *inode,
1353                                               struct ext4_io_end *io_end)
1354 {
1355         if (!(io_end->flag & EXT4_IO_END_UNWRITTEN)) {
1356                 io_end->flag |= EXT4_IO_END_UNWRITTEN;
1357                 atomic_inc(&EXT4_I(inode)->i_unwritten);
1358         }
1359 }
1360
1361 static inline ext4_io_end_t *ext4_inode_aio(struct inode *inode)
1362 {
1363         return inode->i_private;
1364 }
1365
1366 static inline void ext4_inode_aio_set(struct inode *inode, ext4_io_end_t *io)
1367 {
1368         inode->i_private = io;
1369 }
1370
1371 /*
1372  * Inode dynamic state flags
1373  */
1374 enum {
1375         EXT4_STATE_JDATA,               /* journaled data exists */
1376         EXT4_STATE_NEW,                 /* inode is newly created */
1377         EXT4_STATE_XATTR,               /* has in-inode xattrs */
1378         EXT4_STATE_NO_EXPAND,           /* No space for expansion */
1379         EXT4_STATE_DA_ALLOC_CLOSE,      /* Alloc DA blks on close */
1380         EXT4_STATE_EXT_MIGRATE,         /* Inode is migrating */
1381         EXT4_STATE_DIO_UNWRITTEN,       /* need convert on dio done*/
1382         EXT4_STATE_NEWENTRY,            /* File just added to dir */
1383         EXT4_STATE_DELALLOC_RESERVED,   /* blks already reserved for delalloc */
1384         EXT4_STATE_DIOREAD_LOCK,        /* Disable support for dio read
1385                                            nolocking */
1386         EXT4_STATE_MAY_INLINE_DATA,     /* may have in-inode data */
1387 };
1388
1389 #define EXT4_INODE_BIT_FNS(name, field, offset)                         \
1390 static inline int ext4_test_inode_##name(struct inode *inode, int bit)  \
1391 {                                                                       \
1392         return test_bit(bit + (offset), &EXT4_I(inode)->i_##field);     \
1393 }                                                                       \
1394 static inline void ext4_set_inode_##name(struct inode *inode, int bit)  \
1395 {                                                                       \
1396         set_bit(bit + (offset), &EXT4_I(inode)->i_##field);             \
1397 }                                                                       \
1398 static inline void ext4_clear_inode_##name(struct inode *inode, int bit) \
1399 {                                                                       \
1400         clear_bit(bit + (offset), &EXT4_I(inode)->i_##field);           \
1401 }
1402
1403 EXT4_INODE_BIT_FNS(flag, flags, 0)
1404 #if (BITS_PER_LONG < 64)
1405 EXT4_INODE_BIT_FNS(state, state_flags, 0)
1406
1407 static inline void ext4_clear_state_flags(struct ext4_inode_info *ei)
1408 {
1409         (ei)->i_state_flags = 0;
1410 }
1411 #else
1412 EXT4_INODE_BIT_FNS(state, flags, 32)
1413
1414 static inline void ext4_clear_state_flags(struct ext4_inode_info *ei)
1415 {
1416         /* We depend on the fact that callers will set i_flags */
1417 }
1418 #endif
1419 #else
1420 /* Assume that user mode programs are passing in an ext4fs superblock, not
1421  * a kernel struct super_block.  This will allow us to call the feature-test
1422  * macros from user land. */
1423 #define EXT4_SB(sb)     (sb)
1424 #endif
1425
1426 #define NEXT_ORPHAN(inode) EXT4_I(inode)->i_dtime
1427
1428 /*
1429  * Codes for operating systems
1430  */
1431 #define EXT4_OS_LINUX           0
1432 #define EXT4_OS_HURD            1
1433 #define EXT4_OS_MASIX           2
1434 #define EXT4_OS_FREEBSD         3
1435 #define EXT4_OS_LITES           4
1436
1437 /*
1438  * Revision levels
1439  */
1440 #define EXT4_GOOD_OLD_REV       0       /* The good old (original) format */
1441 #define EXT4_DYNAMIC_REV        1       /* V2 format w/ dynamic inode sizes */
1442
1443 #define EXT4_CURRENT_REV        EXT4_GOOD_OLD_REV
1444 #define EXT4_MAX_SUPP_REV       EXT4_DYNAMIC_REV
1445
1446 #define EXT4_GOOD_OLD_INODE_SIZE 128
1447
1448 /*
1449  * Feature set definitions
1450  */
1451
1452 #define EXT4_HAS_COMPAT_FEATURE(sb,mask)                        \
1453         ((EXT4_SB(sb)->s_es->s_feature_compat & cpu_to_le32(mask)) != 0)
1454 #define EXT4_HAS_RO_COMPAT_FEATURE(sb,mask)                     \
1455         ((EXT4_SB(sb)->s_es->s_feature_ro_compat & cpu_to_le32(mask)) != 0)
1456 #define EXT4_HAS_INCOMPAT_FEATURE(sb,mask)                      \
1457         ((EXT4_SB(sb)->s_es->s_feature_incompat & cpu_to_le32(mask)) != 0)
1458 #define EXT4_SET_COMPAT_FEATURE(sb,mask)                        \
1459         EXT4_SB(sb)->s_es->s_feature_compat |= cpu_to_le32(mask)
1460 #define EXT4_SET_RO_COMPAT_FEATURE(sb,mask)                     \
1461         EXT4_SB(sb)->s_es->s_feature_ro_compat |= cpu_to_le32(mask)
1462 #define EXT4_SET_INCOMPAT_FEATURE(sb,mask)                      \
1463         EXT4_SB(sb)->s_es->s_feature_incompat |= cpu_to_le32(mask)
1464 #define EXT4_CLEAR_COMPAT_FEATURE(sb,mask)                      \
1465         EXT4_SB(sb)->s_es->s_feature_compat &= ~cpu_to_le32(mask)
1466 #define EXT4_CLEAR_RO_COMPAT_FEATURE(sb,mask)                   \
1467         EXT4_SB(sb)->s_es->s_feature_ro_compat &= ~cpu_to_le32(mask)
1468 #define EXT4_CLEAR_INCOMPAT_FEATURE(sb,mask)                    \
1469         EXT4_SB(sb)->s_es->s_feature_incompat &= ~cpu_to_le32(mask)
1470
1471 #define EXT4_FEATURE_COMPAT_DIR_PREALLOC        0x0001
1472 #define EXT4_FEATURE_COMPAT_IMAGIC_INODES       0x0002
1473 #define EXT4_FEATURE_COMPAT_HAS_JOURNAL         0x0004
1474 #define EXT4_FEATURE_COMPAT_EXT_ATTR            0x0008
1475 #define EXT4_FEATURE_COMPAT_RESIZE_INODE        0x0010
1476 #define EXT4_FEATURE_COMPAT_DIR_INDEX           0x0020
1477
1478 #define EXT4_FEATURE_RO_COMPAT_SPARSE_SUPER     0x0001
1479 #define EXT4_FEATURE_RO_COMPAT_LARGE_FILE       0x0002
1480 #define EXT4_FEATURE_RO_COMPAT_BTREE_DIR        0x0004
1481 #define EXT4_FEATURE_RO_COMPAT_HUGE_FILE        0x0008
1482 #define EXT4_FEATURE_RO_COMPAT_GDT_CSUM         0x0010
1483 #define EXT4_FEATURE_RO_COMPAT_DIR_NLINK        0x0020
1484 #define EXT4_FEATURE_RO_COMPAT_EXTRA_ISIZE      0x0040
1485 #define EXT4_FEATURE_RO_COMPAT_QUOTA            0x0100
1486 #define EXT4_FEATURE_RO_COMPAT_BIGALLOC         0x0200
1487 /*
1488  * METADATA_CSUM also enables group descriptor checksums (GDT_CSUM).  When
1489  * METADATA_CSUM is set, group descriptor checksums use the same algorithm as
1490  * all other data structures' checksums.  However, the METADATA_CSUM and
1491  * GDT_CSUM bits are mutually exclusive.
1492  */
1493 #define EXT4_FEATURE_RO_COMPAT_METADATA_CSUM    0x0400
1494
1495 #define EXT4_FEATURE_INCOMPAT_COMPRESSION       0x0001
1496 #define EXT4_FEATURE_INCOMPAT_FILETYPE          0x0002
1497 #define EXT4_FEATURE_INCOMPAT_RECOVER           0x0004 /* Needs recovery */
1498 #define EXT4_FEATURE_INCOMPAT_JOURNAL_DEV       0x0008 /* Journal device */
1499 #define EXT4_FEATURE_INCOMPAT_META_BG           0x0010
1500 #define EXT4_FEATURE_INCOMPAT_EXTENTS           0x0040 /* extents support */
1501 #define EXT4_FEATURE_INCOMPAT_64BIT             0x0080
1502 #define EXT4_FEATURE_INCOMPAT_MMP               0x0100
1503 #define EXT4_FEATURE_INCOMPAT_FLEX_BG           0x0200
1504 #define EXT4_FEATURE_INCOMPAT_EA_INODE          0x0400 /* EA in inode */
1505 #define EXT4_FEATURE_INCOMPAT_DIRDATA           0x1000 /* data in dirent */
1506 #define EXT4_FEATURE_INCOMPAT_BG_USE_META_CSUM  0x2000 /* use crc32c for bg */
1507 #define EXT4_FEATURE_INCOMPAT_LARGEDIR          0x4000 /* >2GB or 3-lvl htree */
1508 #define EXT4_FEATURE_INCOMPAT_INLINE_DATA       0x8000 /* data in inode */
1509
1510 #define EXT2_FEATURE_COMPAT_SUPP        EXT4_FEATURE_COMPAT_EXT_ATTR
1511 #define EXT2_FEATURE_INCOMPAT_SUPP      (EXT4_FEATURE_INCOMPAT_FILETYPE| \
1512                                          EXT4_FEATURE_INCOMPAT_META_BG)
1513 #define EXT2_FEATURE_RO_COMPAT_SUPP     (EXT4_FEATURE_RO_COMPAT_SPARSE_SUPER| \
1514                                          EXT4_FEATURE_RO_COMPAT_LARGE_FILE| \
1515                                          EXT4_FEATURE_RO_COMPAT_BTREE_DIR)
1516
1517 #define EXT3_FEATURE_COMPAT_SUPP        EXT4_FEATURE_COMPAT_EXT_ATTR
1518 #define EXT3_FEATURE_INCOMPAT_SUPP      (EXT4_FEATURE_INCOMPAT_FILETYPE| \
1519                                          EXT4_FEATURE_INCOMPAT_RECOVER| \
1520                                          EXT4_FEATURE_INCOMPAT_META_BG)
1521 #define EXT3_FEATURE_RO_COMPAT_SUPP     (EXT4_FEATURE_RO_COMPAT_SPARSE_SUPER| \
1522                                          EXT4_FEATURE_RO_COMPAT_LARGE_FILE| \
1523                                          EXT4_FEATURE_RO_COMPAT_BTREE_DIR)
1524
1525 #define EXT4_FEATURE_COMPAT_SUPP        EXT2_FEATURE_COMPAT_EXT_ATTR
1526 #define EXT4_FEATURE_INCOMPAT_SUPP      (EXT4_FEATURE_INCOMPAT_FILETYPE| \
1527                                          EXT4_FEATURE_INCOMPAT_RECOVER| \
1528                                          EXT4_FEATURE_INCOMPAT_META_BG| \
1529                                          EXT4_FEATURE_INCOMPAT_EXTENTS| \
1530                                          EXT4_FEATURE_INCOMPAT_64BIT| \
1531                                          EXT4_FEATURE_INCOMPAT_FLEX_BG| \
1532                                          EXT4_FEATURE_INCOMPAT_MMP)
1533 #define EXT4_FEATURE_RO_COMPAT_SUPP     (EXT4_FEATURE_RO_COMPAT_SPARSE_SUPER| \
1534                                          EXT4_FEATURE_RO_COMPAT_LARGE_FILE| \
1535                                          EXT4_FEATURE_RO_COMPAT_GDT_CSUM| \
1536                                          EXT4_FEATURE_RO_COMPAT_DIR_NLINK | \
1537                                          EXT4_FEATURE_RO_COMPAT_EXTRA_ISIZE | \
1538                                          EXT4_FEATURE_RO_COMPAT_BTREE_DIR |\
1539                                          EXT4_FEATURE_RO_COMPAT_HUGE_FILE |\
1540                                          EXT4_FEATURE_RO_COMPAT_BIGALLOC |\
1541                                          EXT4_FEATURE_RO_COMPAT_METADATA_CSUM|\
1542                                          EXT4_FEATURE_RO_COMPAT_QUOTA)
1543
1544 /*
1545  * Default values for user and/or group using reserved blocks
1546  */
1547 #define EXT4_DEF_RESUID         0
1548 #define EXT4_DEF_RESGID         0
1549
1550 #define EXT4_DEF_INODE_READAHEAD_BLKS   32
1551
1552 /*
1553  * Default mount options
1554  */
1555 #define EXT4_DEFM_DEBUG         0x0001
1556 #define EXT4_DEFM_BSDGROUPS     0x0002
1557 #define EXT4_DEFM_XATTR_USER    0x0004
1558 #define EXT4_DEFM_ACL           0x0008
1559 #define EXT4_DEFM_UID16         0x0010
1560 #define EXT4_DEFM_JMODE         0x0060
1561 #define EXT4_DEFM_JMODE_DATA    0x0020
1562 #define EXT4_DEFM_JMODE_ORDERED 0x0040
1563 #define EXT4_DEFM_JMODE_WBACK   0x0060
1564 #define EXT4_DEFM_NOBARRIER     0x0100
1565 #define EXT4_DEFM_BLOCK_VALIDITY 0x0200
1566 #define EXT4_DEFM_DISCARD       0x0400
1567 #define EXT4_DEFM_NODELALLOC    0x0800
1568
1569 /*
1570  * Default journal batch times
1571  */
1572 #define EXT4_DEF_MIN_BATCH_TIME 0
1573 #define EXT4_DEF_MAX_BATCH_TIME 15000 /* 15ms */
1574
1575 /*
1576  * Minimum number of groups in a flexgroup before we separate out
1577  * directories into the first block group of a flexgroup
1578  */
1579 #define EXT4_FLEX_SIZE_DIR_ALLOC_SCHEME 4
1580
1581 /*
1582  * Structure of a directory entry
1583  */
1584 #define EXT4_NAME_LEN 255
1585
1586 struct ext4_dir_entry {
1587         __le32  inode;                  /* Inode number */
1588         __le16  rec_len;                /* Directory entry length */
1589         __le16  name_len;               /* Name length */
1590         char    name[EXT4_NAME_LEN];    /* File name */
1591 };
1592
1593 /*
1594  * The new version of the directory entry.  Since EXT4 structures are
1595  * stored in intel byte order, and the name_len field could never be
1596  * bigger than 255 chars, it's safe to reclaim the extra byte for the
1597  * file_type field.
1598  */
1599 struct ext4_dir_entry_2 {
1600         __le32  inode;                  /* Inode number */
1601         __le16  rec_len;                /* Directory entry length */
1602         __u8    name_len;               /* Name length */
1603         __u8    file_type;
1604         char    name[EXT4_NAME_LEN];    /* File name */
1605 };
1606
1607 /*
1608  * This is a bogus directory entry at the end of each leaf block that
1609  * records checksums.
1610  */
1611 struct ext4_dir_entry_tail {
1612         __le32  det_reserved_zero1;     /* Pretend to be unused */
1613         __le16  det_rec_len;            /* 12 */
1614         __u8    det_reserved_zero2;     /* Zero name length */
1615         __u8    det_reserved_ft;        /* 0xDE, fake file type */
1616         __le32  det_checksum;           /* crc32c(uuid+inum+dirblock) */
1617 };
1618
1619 /*
1620  * Ext4 directory file types.  Only the low 3 bits are used.  The
1621  * other bits are reserved for now.
1622  */
1623 #define EXT4_FT_UNKNOWN         0
1624 #define EXT4_FT_REG_FILE        1
1625 #define EXT4_FT_DIR             2
1626 #define EXT4_FT_CHRDEV          3
1627 #define EXT4_FT_BLKDEV          4
1628 #define EXT4_FT_FIFO            5
1629 #define EXT4_FT_SOCK            6
1630 #define EXT4_FT_SYMLINK         7
1631
1632 #define EXT4_FT_MAX             8
1633
1634 #define EXT4_FT_DIR_CSUM        0xDE
1635
1636 /*
1637  * EXT4_DIR_PAD defines the directory entries boundaries
1638  *
1639  * NOTE: It must be a multiple of 4
1640  */
1641 #define EXT4_DIR_PAD                    4
1642 #define EXT4_DIR_ROUND                  (EXT4_DIR_PAD - 1)
1643 #define EXT4_DIR_REC_LEN(name_len)      (((name_len) + 8 + EXT4_DIR_ROUND) & \
1644                                          ~EXT4_DIR_ROUND)
1645 #define EXT4_MAX_REC_LEN                ((1<<16)-1)
1646
1647 /*
1648  * If we ever get support for fs block sizes > page_size, we'll need
1649  * to remove the #if statements in the next two functions...
1650  */
1651 static inline unsigned int
1652 ext4_rec_len_from_disk(__le16 dlen, unsigned blocksize)
1653 {
1654         unsigned len = le16_to_cpu(dlen);
1655
1656 #if (PAGE_CACHE_SIZE >= 65536)
1657         if (len == EXT4_MAX_REC_LEN || len == 0)
1658                 return blocksize;
1659         return (len & 65532) | ((len & 3) << 16);
1660 #else
1661         return len;
1662 #endif
1663 }
1664
1665 static inline __le16 ext4_rec_len_to_disk(unsigned len, unsigned blocksize)
1666 {
1667         if ((len > blocksize) || (blocksize > (1 << 18)) || (len & 3))
1668                 BUG();
1669 #if (PAGE_CACHE_SIZE >= 65536)
1670         if (len < 65536)
1671                 return cpu_to_le16(len);
1672         if (len == blocksize) {
1673                 if (blocksize == 65536)
1674                         return cpu_to_le16(EXT4_MAX_REC_LEN);
1675                 else
1676                         return cpu_to_le16(0);
1677         }
1678         return cpu_to_le16((len & 65532) | ((len >> 16) & 3));
1679 #else
1680         return cpu_to_le16(len);
1681 #endif
1682 }
1683
1684 /*
1685  * Hash Tree Directory indexing
1686  * (c) Daniel Phillips, 2001
1687  */
1688
1689 #define is_dx(dir) (EXT4_HAS_COMPAT_FEATURE(dir->i_sb, \
1690                                       EXT4_FEATURE_COMPAT_DIR_INDEX) && \
1691                     ext4_test_inode_flag((dir), EXT4_INODE_INDEX))
1692 #define EXT4_DIR_LINK_MAX(dir) (!is_dx(dir) && (dir)->i_nlink >= EXT4_LINK_MAX)
1693 #define EXT4_DIR_LINK_EMPTY(dir) ((dir)->i_nlink == 2 || (dir)->i_nlink == 1)
1694
1695 /* Legal values for the dx_root hash_version field: */
1696
1697 #define DX_HASH_LEGACY          0
1698 #define DX_HASH_HALF_MD4        1
1699 #define DX_HASH_TEA             2
1700 #define DX_HASH_LEGACY_UNSIGNED 3
1701 #define DX_HASH_HALF_MD4_UNSIGNED       4
1702 #define DX_HASH_TEA_UNSIGNED            5
1703
1704 static inline u32 ext4_chksum(struct ext4_sb_info *sbi, u32 crc,
1705                               const void *address, unsigned int length)
1706 {
1707         struct {
1708                 struct shash_desc shash;
1709                 char ctx[4];
1710         } desc;
1711         int err;
1712
1713         BUG_ON(crypto_shash_descsize(sbi->s_chksum_driver)!=sizeof(desc.ctx));
1714
1715         desc.shash.tfm = sbi->s_chksum_driver;
1716         desc.shash.flags = 0;
1717         *(u32 *)desc.ctx = crc;
1718
1719         err = crypto_shash_update(&desc.shash, address, length);
1720         BUG_ON(err);
1721
1722         return *(u32 *)desc.ctx;
1723 }
1724
1725 #ifdef __KERNEL__
1726
1727 /* hash info structure used by the directory hash */
1728 struct dx_hash_info
1729 {
1730         u32             hash;
1731         u32             minor_hash;
1732         int             hash_version;
1733         u32             *seed;
1734 };
1735
1736
1737 /* 32 and 64 bit signed EOF for dx directories */
1738 #define EXT4_HTREE_EOF_32BIT   ((1UL  << (32 - 1)) - 1)
1739 #define EXT4_HTREE_EOF_64BIT   ((1ULL << (64 - 1)) - 1)
1740
1741
1742 /*
1743  * Control parameters used by ext4_htree_next_block
1744  */
1745 #define HASH_NB_ALWAYS          1
1746
1747
1748 /*
1749  * Describe an inode's exact location on disk and in memory
1750  */
1751 struct ext4_iloc
1752 {
1753         struct buffer_head *bh;
1754         unsigned long offset;
1755         ext4_group_t block_group;
1756 };
1757
1758 static inline struct ext4_inode *ext4_raw_inode(struct ext4_iloc *iloc)
1759 {
1760         return (struct ext4_inode *) (iloc->bh->b_data + iloc->offset);
1761 }
1762
1763 /*
1764  * This structure is stuffed into the struct file's private_data field
1765  * for directories.  It is where we put information so that we can do
1766  * readdir operations in hash tree order.
1767  */
1768 struct dir_private_info {
1769         struct rb_root  root;
1770         struct rb_node  *curr_node;
1771         struct fname    *extra_fname;
1772         loff_t          last_pos;
1773         __u32           curr_hash;
1774         __u32           curr_minor_hash;
1775         __u32           next_hash;
1776 };
1777
1778 /* calculate the first block number of the group */
1779 static inline ext4_fsblk_t
1780 ext4_group_first_block_no(struct super_block *sb, ext4_group_t group_no)
1781 {
1782         return group_no * (ext4_fsblk_t)EXT4_BLOCKS_PER_GROUP(sb) +
1783                 le32_to_cpu(EXT4_SB(sb)->s_es->s_first_data_block);
1784 }
1785
1786 /*
1787  * Special error return code only used by dx_probe() and its callers.
1788  */
1789 #define ERR_BAD_DX_DIR  -75000
1790
1791 void ext4_get_group_no_and_offset(struct super_block *sb, ext4_fsblk_t blocknr,
1792                         ext4_group_t *blockgrpp, ext4_grpblk_t *offsetp);
1793
1794 /*
1795  * Timeout and state flag for lazy initialization inode thread.
1796  */
1797 #define EXT4_DEF_LI_WAIT_MULT                   10
1798 #define EXT4_DEF_LI_MAX_START_DELAY             5
1799 #define EXT4_LAZYINIT_QUIT                      0x0001
1800 #define EXT4_LAZYINIT_RUNNING                   0x0002
1801
1802 /*
1803  * Lazy inode table initialization info
1804  */
1805 struct ext4_lazy_init {
1806         unsigned long           li_state;
1807         struct list_head        li_request_list;
1808         struct mutex            li_list_mtx;
1809 };
1810
1811 struct ext4_li_request {
1812         struct super_block      *lr_super;
1813         struct ext4_sb_info     *lr_sbi;
1814         ext4_group_t            lr_next_group;
1815         struct list_head        lr_request;
1816         unsigned long           lr_next_sched;
1817         unsigned long           lr_timeout;
1818 };
1819
1820 struct ext4_features {
1821         struct kobject f_kobj;
1822         struct completion f_kobj_unregister;
1823 };
1824
1825 /*
1826  * This structure will be used for multiple mount protection. It will be
1827  * written into the block number saved in the s_mmp_block field in the
1828  * superblock. Programs that check MMP should assume that if
1829  * SEQ_FSCK (or any unknown code above SEQ_MAX) is present then it is NOT safe
1830  * to use the filesystem, regardless of how old the timestamp is.
1831  */
1832 #define EXT4_MMP_MAGIC     0x004D4D50U /* ASCII for MMP */
1833 #define EXT4_MMP_SEQ_CLEAN 0xFF4D4D50U /* mmp_seq value for clean unmount */
1834 #define EXT4_MMP_SEQ_FSCK  0xE24D4D50U /* mmp_seq value when being fscked */
1835 #define EXT4_MMP_SEQ_MAX   0xE24D4D4FU /* maximum valid mmp_seq value */
1836
1837 struct mmp_struct {
1838         __le32  mmp_magic;              /* Magic number for MMP */
1839         __le32  mmp_seq;                /* Sequence no. updated periodically */
1840
1841         /*
1842          * mmp_time, mmp_nodename & mmp_bdevname are only used for information
1843          * purposes and do not affect the correctness of the algorithm
1844          */
1845         __le64  mmp_time;               /* Time last updated */
1846         char    mmp_nodename[64];       /* Node which last updated MMP block */
1847         char    mmp_bdevname[32];       /* Bdev which last updated MMP block */
1848
1849         /*
1850          * mmp_check_interval is used to verify if the MMP block has been
1851          * updated on the block device. The value is updated based on the
1852          * maximum time to write the MMP block during an update cycle.
1853          */
1854         __le16  mmp_check_interval;
1855
1856         __le16  mmp_pad1;
1857         __le32  mmp_pad2[226];
1858         __le32  mmp_checksum;           /* crc32c(uuid+mmp_block) */
1859 };
1860
1861 /* arguments passed to the mmp thread */
1862 struct mmpd_data {
1863         struct buffer_head *bh; /* bh from initial read_mmp_block() */
1864         struct super_block *sb;  /* super block of the fs */
1865 };
1866
1867 /*
1868  * Check interval multiplier
1869  * The MMP block is written every update interval and initially checked every
1870  * update interval x the multiplier (the value is then adapted based on the
1871  * write latency). The reason is that writes can be delayed under load and we
1872  * don't want readers to incorrectly assume that the filesystem is no longer
1873  * in use.
1874  */
1875 #define EXT4_MMP_CHECK_MULT             2UL
1876
1877 /*
1878  * Minimum interval for MMP checking in seconds.
1879  */
1880 #define EXT4_MMP_MIN_CHECK_INTERVAL     5UL
1881
1882 /*
1883  * Maximum interval for MMP checking in seconds.
1884  */
1885 #define EXT4_MMP_MAX_CHECK_INTERVAL     300UL
1886
1887 /*
1888  * Function prototypes
1889  */
1890
1891 /*
1892  * Ok, these declarations are also in <linux/kernel.h> but none of the
1893  * ext4 source programs needs to include it so they are duplicated here.
1894  */
1895 # define NORET_TYPE     /**/
1896 # define ATTRIB_NORET   __attribute__((noreturn))
1897 # define NORET_AND      noreturn,
1898
1899 /* bitmap.c */
1900 extern unsigned int ext4_count_free(char *bitmap, unsigned numchars);
1901 void ext4_inode_bitmap_csum_set(struct super_block *sb, ext4_group_t group,
1902                                 struct ext4_group_desc *gdp,
1903                                 struct buffer_head *bh, int sz);
1904 int ext4_inode_bitmap_csum_verify(struct super_block *sb, ext4_group_t group,
1905                                   struct ext4_group_desc *gdp,
1906                                   struct buffer_head *bh, int sz);
1907 void ext4_block_bitmap_csum_set(struct super_block *sb, ext4_group_t group,
1908                                 struct ext4_group_desc *gdp,
1909                                 struct buffer_head *bh);
1910 int ext4_block_bitmap_csum_verify(struct super_block *sb, ext4_group_t group,
1911                                   struct ext4_group_desc *gdp,
1912                                   struct buffer_head *bh);
1913
1914 /* balloc.c */
1915 extern void ext4_validate_block_bitmap(struct super_block *sb,
1916                                        struct ext4_group_desc *desc,
1917                                        unsigned int block_group,
1918                                        struct buffer_head *bh);
1919 extern unsigned int ext4_block_group(struct super_block *sb,
1920                         ext4_fsblk_t blocknr);
1921 extern ext4_grpblk_t ext4_block_group_offset(struct super_block *sb,
1922                         ext4_fsblk_t blocknr);
1923 extern int ext4_bg_has_super(struct super_block *sb, ext4_group_t group);
1924 extern unsigned long ext4_bg_num_gdb(struct super_block *sb,
1925                         ext4_group_t group);
1926 extern ext4_fsblk_t ext4_new_meta_blocks(handle_t *handle, struct inode *inode,
1927                                          ext4_fsblk_t goal,
1928                                          unsigned int flags,
1929                                          unsigned long *count,
1930                                          int *errp);
1931 extern int ext4_claim_free_clusters(struct ext4_sb_info *sbi,
1932                                     s64 nclusters, unsigned int flags);
1933 extern ext4_fsblk_t ext4_count_free_clusters(struct super_block *);
1934 extern void ext4_check_blocks_bitmap(struct super_block *);
1935 extern struct ext4_group_desc * ext4_get_group_desc(struct super_block * sb,
1936                                                     ext4_group_t block_group,
1937                                                     struct buffer_head ** bh);
1938 extern int ext4_should_retry_alloc(struct super_block *sb, int *retries);
1939
1940 extern struct buffer_head *ext4_read_block_bitmap_nowait(struct super_block *sb,
1941                                                 ext4_group_t block_group);
1942 extern int ext4_wait_block_bitmap(struct super_block *sb,
1943                                   ext4_group_t block_group,
1944                                   struct buffer_head *bh);
1945 extern struct buffer_head *ext4_read_block_bitmap(struct super_block *sb,
1946                                                   ext4_group_t block_group);
1947 extern void ext4_init_block_bitmap(struct super_block *sb,
1948                                    struct buffer_head *bh,
1949                                    ext4_group_t group,
1950                                    struct ext4_group_desc *desc);
1951 extern unsigned ext4_free_clusters_after_init(struct super_block *sb,
1952                                               ext4_group_t block_group,
1953                                               struct ext4_group_desc *gdp);
1954 extern unsigned ext4_num_overhead_clusters(struct super_block *sb,
1955                                            ext4_group_t block_group,
1956                                            struct ext4_group_desc *gdp);
1957 ext4_fsblk_t ext4_inode_to_goal_block(struct inode *);
1958
1959 /* dir.c */
1960 extern int __ext4_check_dir_entry(const char *, unsigned int, struct inode *,
1961                                   struct file *,
1962                                   struct ext4_dir_entry_2 *,
1963                                   struct buffer_head *, unsigned int);
1964 #define ext4_check_dir_entry(dir, filp, de, bh, offset)                 \
1965         unlikely(__ext4_check_dir_entry(__func__, __LINE__, (dir), (filp), \
1966                                         (de), (bh), (offset)))
1967 extern int ext4_htree_store_dirent(struct file *dir_file, __u32 hash,
1968                                     __u32 minor_hash,
1969                                     struct ext4_dir_entry_2 *dirent);
1970 extern void ext4_htree_free_dir_info(struct dir_private_info *p);
1971
1972 /* fsync.c */
1973 extern int ext4_sync_file(struct file *, loff_t, loff_t, int);
1974 extern int ext4_flush_unwritten_io(struct inode *);
1975
1976 /* hash.c */
1977 extern int ext4fs_dirhash(const char *name, int len, struct
1978                           dx_hash_info *hinfo);
1979
1980 /* ialloc.c */
1981 extern struct inode *ext4_new_inode(handle_t *, struct inode *, umode_t,
1982                                     const struct qstr *qstr, __u32 goal,
1983                                     uid_t *owner);
1984 extern void ext4_free_inode(handle_t *, struct inode *);
1985 extern struct inode * ext4_orphan_get(struct super_block *, unsigned long);
1986 extern unsigned long ext4_count_free_inodes(struct super_block *);
1987 extern unsigned long ext4_count_dirs(struct super_block *);
1988 extern void ext4_check_inodes_bitmap(struct super_block *);
1989 extern void ext4_mark_bitmap_end(int start_bit, int end_bit, char *bitmap);
1990 extern int ext4_init_inode_table(struct super_block *sb,
1991                                  ext4_group_t group, int barrier);
1992 extern void ext4_end_bitmap_read(struct buffer_head *bh, int uptodate);
1993
1994 /* mballoc.c */
1995 extern long ext4_mb_stats;
1996 extern long ext4_mb_max_to_scan;
1997 extern int ext4_mb_init(struct super_block *);
1998 extern int ext4_mb_release(struct super_block *);
1999 extern ext4_fsblk_t ext4_mb_new_blocks(handle_t *,
2000                                 struct ext4_allocation_request *, int *);
2001 extern int ext4_mb_reserve_blocks(struct super_block *, int);
2002 extern void ext4_discard_preallocations(struct inode *);
2003 extern int __init ext4_init_mballoc(void);
2004 extern void ext4_exit_mballoc(void);
2005 extern void ext4_free_blocks(handle_t *handle, struct inode *inode,
2006                              struct buffer_head *bh, ext4_fsblk_t block,
2007                              unsigned long count, int flags);
2008 extern int ext4_mb_alloc_groupinfo(struct super_block *sb,
2009                                    ext4_group_t ngroups);
2010 extern int ext4_mb_add_groupinfo(struct super_block *sb,
2011                 ext4_group_t i, struct ext4_group_desc *desc);
2012 extern int ext4_group_add_blocks(handle_t *handle, struct super_block *sb,
2013                                 ext4_fsblk_t block, unsigned long count);
2014 extern int ext4_trim_fs(struct super_block *, struct fstrim_range *);
2015
2016 /* inode.c */
2017 struct buffer_head *ext4_getblk(handle_t *, struct inode *,
2018                                                 ext4_lblk_t, int, int *);
2019 struct buffer_head *ext4_bread(handle_t *, struct inode *,
2020                                                 ext4_lblk_t, int, int *);
2021 int ext4_get_block_write(struct inode *inode, sector_t iblock,
2022                          struct buffer_head *bh_result, int create);
2023 int ext4_get_block(struct inode *inode, sector_t iblock,
2024                                 struct buffer_head *bh_result, int create);
2025 int ext4_da_get_block_prep(struct inode *inode, sector_t iblock,
2026                            struct buffer_head *bh, int create);
2027 int ext4_walk_page_buffers(handle_t *handle,
2028                            struct buffer_head *head,
2029                            unsigned from,
2030                            unsigned to,
2031                            int *partial,
2032                            int (*fn)(handle_t *handle,
2033                                      struct buffer_head *bh));
2034 int do_journal_get_write_access(handle_t *handle,
2035                                 struct buffer_head *bh);
2036 #define FALL_BACK_TO_NONDELALLOC 1
2037 #define CONVERT_INLINE_DATA      2
2038
2039 extern struct inode *ext4_iget(struct super_block *, unsigned long);
2040 extern int  ext4_write_inode(struct inode *, struct writeback_control *);
2041 extern int  ext4_setattr(struct dentry *, struct iattr *);
2042 extern int  ext4_getattr(struct vfsmount *mnt, struct dentry *dentry,
2043                                 struct kstat *stat);
2044 extern void ext4_evict_inode(struct inode *);
2045 extern void ext4_clear_inode(struct inode *);
2046 extern int  ext4_sync_inode(handle_t *, struct inode *);
2047 extern void ext4_dirty_inode(struct inode *, int);
2048 extern int ext4_change_inode_journal_flag(struct inode *, int);
2049 extern int ext4_get_inode_loc(struct inode *, struct ext4_iloc *);
2050 extern int ext4_can_truncate(struct inode *inode);
2051 extern void ext4_truncate(struct inode *);
2052 extern int ext4_punch_hole(struct file *file, loff_t offset, loff_t length);
2053 extern int ext4_truncate_restart_trans(handle_t *, struct inode *, int nblocks);
2054 extern void ext4_set_inode_flags(struct inode *);
2055 extern void ext4_get_inode_flags(struct ext4_inode_info *);
2056 extern int ext4_alloc_da_blocks(struct inode *inode);
2057 extern void ext4_set_aops(struct inode *inode);
2058 extern int ext4_writepage_trans_blocks(struct inode *);
2059 extern int ext4_chunk_trans_blocks(struct inode *, int nrblocks);
2060 extern int ext4_discard_partial_page_buffers(handle_t *handle,
2061                 struct address_space *mapping, loff_t from,
2062                 loff_t length, int flags);
2063 extern int ext4_page_mkwrite(struct vm_area_struct *vma, struct vm_fault *vmf);
2064 extern qsize_t *ext4_get_reserved_space(struct inode *inode);
2065 extern void ext4_da_update_reserve_space(struct inode *inode,
2066                                         int used, int quota_claim);
2067
2068 /* indirect.c */
2069 extern int ext4_ind_map_blocks(handle_t *handle, struct inode *inode,
2070                                 struct ext4_map_blocks *map, int flags);
2071 extern ssize_t ext4_ind_direct_IO(int rw, struct kiocb *iocb,
2072                                 const struct iovec *iov, loff_t offset,
2073                                 unsigned long nr_segs);
2074 extern int ext4_ind_calc_metadata_amount(struct inode *inode, sector_t lblock);
2075 extern int ext4_ind_trans_blocks(struct inode *inode, int nrblocks, int chunk);
2076 extern void ext4_ind_truncate(struct inode *inode);
2077
2078 /* ioctl.c */
2079 extern long ext4_ioctl(struct file *, unsigned int, unsigned long);
2080 extern long ext4_compat_ioctl(struct file *, unsigned int, unsigned long);
2081
2082 /* migrate.c */
2083 extern int ext4_ext_migrate(struct inode *);
2084
2085 /* namei.c */
2086 extern int ext4_dirent_csum_verify(struct inode *inode,
2087                                    struct ext4_dir_entry *dirent);
2088 extern int ext4_orphan_add(handle_t *, struct inode *);
2089 extern int ext4_orphan_del(handle_t *, struct inode *);
2090 extern int ext4_htree_fill_tree(struct file *dir_file, __u32 start_hash,
2091                                 __u32 start_minor_hash, __u32 *next_hash);
2092
2093 /* resize.c */
2094 extern int ext4_group_add(struct super_block *sb,
2095                                 struct ext4_new_group_data *input);
2096 extern int ext4_group_extend(struct super_block *sb,
2097                                 struct ext4_super_block *es,
2098                                 ext4_fsblk_t n_blocks_count);
2099 extern int ext4_resize_fs(struct super_block *sb, ext4_fsblk_t n_blocks_count);
2100
2101 /* super.c */
2102 extern int ext4_calculate_overhead(struct super_block *sb);
2103 extern int ext4_superblock_csum_verify(struct super_block *sb,
2104                                        struct ext4_super_block *es);
2105 extern void ext4_superblock_csum_set(struct super_block *sb);
2106 extern void *ext4_kvmalloc(size_t size, gfp_t flags);
2107 extern void *ext4_kvzalloc(size_t size, gfp_t flags);
2108 extern void ext4_kvfree(void *ptr);
2109 extern int ext4_alloc_flex_bg_array(struct super_block *sb,
2110                                     ext4_group_t ngroup);
2111 extern __printf(4, 5)
2112 void __ext4_error(struct super_block *, const char *, unsigned int,
2113                   const char *, ...);
2114 #define ext4_error(sb, message...)      __ext4_error(sb, __func__,      \
2115                                                      __LINE__, ## message)
2116 extern __printf(5, 6)
2117 void ext4_error_inode(struct inode *, const char *, unsigned int, ext4_fsblk_t,
2118                       const char *, ...);
2119 extern __printf(5, 6)
2120 void ext4_error_file(struct file *, const char *, unsigned int, ext4_fsblk_t,
2121                      const char *, ...);
2122 extern void __ext4_std_error(struct super_block *, const char *,
2123                              unsigned int, int);
2124 extern __printf(4, 5)
2125 void __ext4_abort(struct super_block *, const char *, unsigned int,
2126                   const char *, ...);
2127 #define ext4_abort(sb, message...)      __ext4_abort(sb, __func__, \
2128                                                        __LINE__, ## message)
2129 extern __printf(4, 5)
2130 void __ext4_warning(struct super_block *, const char *, unsigned int,
2131                     const char *, ...);
2132 #define ext4_warning(sb, message...)    __ext4_warning(sb, __func__, \
2133                                                        __LINE__, ## message)
2134 extern __printf(3, 4)
2135 void ext4_msg(struct super_block *, const char *, const char *, ...);
2136 extern void __dump_mmp_msg(struct super_block *, struct mmp_struct *mmp,
2137                            const char *, unsigned int, const char *);
2138 #define dump_mmp_msg(sb, mmp, msg)      __dump_mmp_msg(sb, mmp, __func__, \
2139                                                        __LINE__, msg)
2140 extern __printf(7, 8)
2141 void __ext4_grp_locked_error(const char *, unsigned int,
2142                              struct super_block *, ext4_group_t,
2143                              unsigned long, ext4_fsblk_t,
2144                              const char *, ...);
2145 #define ext4_grp_locked_error(sb, grp, message...) \
2146         __ext4_grp_locked_error(__func__, __LINE__, (sb), (grp), ## message)
2147 extern void ext4_update_dynamic_rev(struct super_block *sb);
2148 extern int ext4_update_compat_feature(handle_t *handle, struct super_block *sb,
2149                                         __u32 compat);
2150 extern int ext4_update_rocompat_feature(handle_t *handle,
2151                                         struct super_block *sb, __u32 rocompat);
2152 extern int ext4_update_incompat_feature(handle_t *handle,
2153                                         struct super_block *sb, __u32 incompat);
2154 extern ext4_fsblk_t ext4_block_bitmap(struct super_block *sb,
2155                                       struct ext4_group_desc *bg);
2156 extern ext4_fsblk_t ext4_inode_bitmap(struct super_block *sb,
2157                                       struct ext4_group_desc *bg);
2158 extern ext4_fsblk_t ext4_inode_table(struct super_block *sb,
2159                                      struct ext4_group_desc *bg);
2160 extern __u32 ext4_free_group_clusters(struct super_block *sb,
2161                                       struct ext4_group_desc *bg);
2162 extern __u32 ext4_free_inodes_count(struct super_block *sb,
2163                                  struct ext4_group_desc *bg);
2164 extern __u32 ext4_used_dirs_count(struct super_block *sb,
2165                                 struct ext4_group_desc *bg);
2166 extern __u32 ext4_itable_unused_count(struct super_block *sb,
2167                                    struct ext4_group_desc *bg);
2168 extern void ext4_block_bitmap_set(struct super_block *sb,
2169                                   struct ext4_group_desc *bg, ext4_fsblk_t blk);
2170 extern void ext4_inode_bitmap_set(struct super_block *sb,
2171                                   struct ext4_group_desc *bg, ext4_fsblk_t blk);
2172 extern void ext4_inode_table_set(struct super_block *sb,
2173                                  struct ext4_group_desc *bg, ext4_fsblk_t blk);
2174 extern void ext4_free_group_clusters_set(struct super_block *sb,
2175                                          struct ext4_group_desc *bg,
2176                                          __u32 count);
2177 extern void ext4_free_inodes_set(struct super_block *sb,
2178                                 struct ext4_group_desc *bg, __u32 count);
2179 extern void ext4_used_dirs_set(struct super_block *sb,
2180                                 struct ext4_group_desc *bg, __u32 count);
2181 extern void ext4_itable_unused_set(struct super_block *sb,
2182                                    struct ext4_group_desc *bg, __u32 count);
2183 extern int ext4_group_desc_csum_verify(struct super_block *sb, __u32 group,
2184                                        struct ext4_group_desc *gdp);
2185 extern void ext4_group_desc_csum_set(struct super_block *sb, __u32 group,
2186                                      struct ext4_group_desc *gdp);
2187
2188 static inline int ext4_has_group_desc_csum(struct super_block *sb)
2189 {
2190         return EXT4_HAS_RO_COMPAT_FEATURE(sb,
2191                                           EXT4_FEATURE_RO_COMPAT_GDT_CSUM |
2192                                           EXT4_FEATURE_RO_COMPAT_METADATA_CSUM);
2193 }
2194
2195 static inline ext4_fsblk_t ext4_blocks_count(struct ext4_super_block *es)
2196 {
2197         return ((ext4_fsblk_t)le32_to_cpu(es->s_blocks_count_hi) << 32) |
2198                 le32_to_cpu(es->s_blocks_count_lo);
2199 }
2200
2201 static inline ext4_fsblk_t ext4_r_blocks_count(struct ext4_super_block *es)
2202 {
2203         return ((ext4_fsblk_t)le32_to_cpu(es->s_r_blocks_count_hi) << 32) |
2204                 le32_to_cpu(es->s_r_blocks_count_lo);
2205 }
2206
2207 static inline ext4_fsblk_t ext4_free_blocks_count(struct ext4_super_block *es)
2208 {
2209         return ((ext4_fsblk_t)le32_to_cpu(es->s_free_blocks_count_hi) << 32) |
2210                 le32_to_cpu(es->s_free_blocks_count_lo);
2211 }
2212
2213 static inline void ext4_blocks_count_set(struct ext4_super_block *es,
2214                                          ext4_fsblk_t blk)
2215 {
2216         es->s_blocks_count_lo = cpu_to_le32((u32)blk);
2217         es->s_blocks_count_hi = cpu_to_le32(blk >> 32);
2218 }
2219
2220 static inline void ext4_free_blocks_count_set(struct ext4_super_block *es,
2221                                               ext4_fsblk_t blk)
2222 {
2223         es->s_free_blocks_count_lo = cpu_to_le32((u32)blk);
2224         es->s_free_blocks_count_hi = cpu_to_le32(blk >> 32);
2225 }
2226
2227 static inline void ext4_r_blocks_count_set(struct ext4_super_block *es,
2228                                            ext4_fsblk_t blk)
2229 {
2230         es->s_r_blocks_count_lo = cpu_to_le32((u32)blk);
2231         es->s_r_blocks_count_hi = cpu_to_le32(blk >> 32);
2232 }
2233
2234 static inline loff_t ext4_isize(struct ext4_inode *raw_inode)
2235 {
2236         if (S_ISREG(le16_to_cpu(raw_inode->i_mode)))
2237                 return ((loff_t)le32_to_cpu(raw_inode->i_size_high) << 32) |
2238                         le32_to_cpu(raw_inode->i_size_lo);
2239         else
2240                 return (loff_t) le32_to_cpu(raw_inode->i_size_lo);
2241 }
2242
2243 static inline void ext4_isize_set(struct ext4_inode *raw_inode, loff_t i_size)
2244 {
2245         raw_inode->i_size_lo = cpu_to_le32(i_size);
2246         raw_inode->i_size_high = cpu_to_le32(i_size >> 32);
2247 }
2248
2249 static inline
2250 struct ext4_group_info *ext4_get_group_info(struct super_block *sb,
2251                                             ext4_group_t group)
2252 {
2253          struct ext4_group_info ***grp_info;
2254          long indexv, indexh;
2255          grp_info = EXT4_SB(sb)->s_group_info;
2256          indexv = group >> (EXT4_DESC_PER_BLOCK_BITS(sb));
2257          indexh = group & ((EXT4_DESC_PER_BLOCK(sb)) - 1);
2258          return grp_info[indexv][indexh];
2259 }
2260
2261 /*
2262  * Reading s_groups_count requires using smp_rmb() afterwards.  See
2263  * the locking protocol documented in the comments of ext4_group_add()
2264  * in resize.c
2265  */
2266 static inline ext4_group_t ext4_get_groups_count(struct super_block *sb)
2267 {
2268         ext4_group_t    ngroups = EXT4_SB(sb)->s_groups_count;
2269
2270         smp_rmb();
2271         return ngroups;
2272 }
2273
2274 static inline ext4_group_t ext4_flex_group(struct ext4_sb_info *sbi,
2275                                              ext4_group_t block_group)
2276 {
2277         return block_group >> sbi->s_log_groups_per_flex;
2278 }
2279
2280 static inline unsigned int ext4_flex_bg_size(struct ext4_sb_info *sbi)
2281 {
2282         return 1 << sbi->s_log_groups_per_flex;
2283 }
2284
2285 #define ext4_std_error(sb, errno)                               \
2286 do {                                                            \
2287         if ((errno))                                            \
2288                 __ext4_std_error((sb), __func__, __LINE__, (errno));    \
2289 } while (0)
2290
2291 #ifdef CONFIG_SMP
2292 /* Each CPU can accumulate percpu_counter_batch clusters in their local
2293  * counters. So we need to make sure we have free clusters more
2294  * than percpu_counter_batch  * nr_cpu_ids. Also add a window of 4 times.
2295  */
2296 #define EXT4_FREECLUSTERS_WATERMARK (4 * (percpu_counter_batch * nr_cpu_ids))
2297 #else
2298 #define EXT4_FREECLUSTERS_WATERMARK 0
2299 #endif
2300
2301 static inline void ext4_update_i_disksize(struct inode *inode, loff_t newsize)
2302 {
2303         /*
2304          * XXX: replace with spinlock if seen contended -bzzz
2305          */
2306         down_write(&EXT4_I(inode)->i_data_sem);
2307         if (newsize > EXT4_I(inode)->i_disksize)
2308                 EXT4_I(inode)->i_disksize = newsize;
2309         up_write(&EXT4_I(inode)->i_data_sem);
2310         return ;
2311 }
2312
2313 struct ext4_group_info {
2314         unsigned long   bb_state;
2315         struct rb_root  bb_free_root;
2316         ext4_grpblk_t   bb_first_free;  /* first free block */
2317         ext4_grpblk_t   bb_free;        /* total free blocks */
2318         ext4_grpblk_t   bb_fragments;   /* nr of freespace fragments */
2319         ext4_grpblk_t   bb_largest_free_order;/* order of largest frag in BG */
2320         struct          list_head bb_prealloc_list;
2321 #ifdef DOUBLE_CHECK
2322         void            *bb_bitmap;
2323 #endif
2324         struct rw_semaphore alloc_sem;
2325         ext4_grpblk_t   bb_counters[];  /* Nr of free power-of-two-block
2326                                          * regions, index is order.
2327                                          * bb_counters[3] = 5 means
2328                                          * 5 free 8-block regions. */
2329 };
2330
2331 #define EXT4_GROUP_INFO_NEED_INIT_BIT           0
2332 #define EXT4_GROUP_INFO_WAS_TRIMMED_BIT         1
2333
2334 #define EXT4_MB_GRP_NEED_INIT(grp)      \
2335         (test_bit(EXT4_GROUP_INFO_NEED_INIT_BIT, &((grp)->bb_state)))
2336
2337 #define EXT4_MB_GRP_WAS_TRIMMED(grp)    \
2338         (test_bit(EXT4_GROUP_INFO_WAS_TRIMMED_BIT, &((grp)->bb_state)))
2339 #define EXT4_MB_GRP_SET_TRIMMED(grp)    \
2340         (set_bit(EXT4_GROUP_INFO_WAS_TRIMMED_BIT, &((grp)->bb_state)))
2341 #define EXT4_MB_GRP_CLEAR_TRIMMED(grp)  \
2342         (clear_bit(EXT4_GROUP_INFO_WAS_TRIMMED_BIT, &((grp)->bb_state)))
2343
2344 #define EXT4_MAX_CONTENTION             8
2345 #define EXT4_CONTENTION_THRESHOLD       2
2346
2347 static inline spinlock_t *ext4_group_lock_ptr(struct super_block *sb,
2348                                               ext4_group_t group)
2349 {
2350         return bgl_lock_ptr(EXT4_SB(sb)->s_blockgroup_lock, group);
2351 }
2352
2353 /*
2354  * Returns true if the filesystem is busy enough that attempts to
2355  * access the block group locks has run into contention.
2356  */
2357 static inline int ext4_fs_is_busy(struct ext4_sb_info *sbi)
2358 {
2359         return (atomic_read(&sbi->s_lock_busy) > EXT4_CONTENTION_THRESHOLD);
2360 }
2361
2362 static inline void ext4_lock_group(struct super_block *sb, ext4_group_t group)
2363 {
2364         spinlock_t *lock = ext4_group_lock_ptr(sb, group);
2365         if (spin_trylock(lock))
2366                 /*
2367                  * We're able to grab the lock right away, so drop the
2368                  * lock contention counter.
2369                  */
2370                 atomic_add_unless(&EXT4_SB(sb)->s_lock_busy, -1, 0);
2371         else {
2372                 /*
2373                  * The lock is busy, so bump the contention counter,
2374                  * and then wait on the spin lock.
2375                  */
2376                 atomic_add_unless(&EXT4_SB(sb)->s_lock_busy, 1,
2377                                   EXT4_MAX_CONTENTION);
2378                 spin_lock(lock);
2379         }
2380 }
2381
2382 static inline void ext4_unlock_group(struct super_block *sb,
2383                                         ext4_group_t group)
2384 {
2385         spin_unlock(ext4_group_lock_ptr(sb, group));
2386 }
2387
2388 /*
2389  * Block validity checking
2390  */
2391 #define ext4_check_indirect_blockref(inode, bh)                         \
2392         ext4_check_blockref(__func__, __LINE__, inode,                  \
2393                             (__le32 *)(bh)->b_data,                     \
2394                             EXT4_ADDR_PER_BLOCK((inode)->i_sb))
2395
2396 #define ext4_ind_check_inode(inode)                                     \
2397         ext4_check_blockref(__func__, __LINE__, inode,                  \
2398                             EXT4_I(inode)->i_data,                      \
2399                             EXT4_NDIR_BLOCKS)
2400
2401 /*
2402  * Inodes and files operations
2403  */
2404
2405 /* dir.c */
2406 extern const struct file_operations ext4_dir_operations;
2407
2408 /* file.c */
2409 extern const struct inode_operations ext4_file_inode_operations;
2410 extern const struct file_operations ext4_file_operations;
2411 extern loff_t ext4_llseek(struct file *file, loff_t offset, int origin);
2412 extern void ext4_unwritten_wait(struct inode *inode);
2413
2414 /* namei.c */
2415 extern const struct inode_operations ext4_dir_inode_operations;
2416 extern const struct inode_operations ext4_special_inode_operations;
2417 extern struct dentry *ext4_get_parent(struct dentry *child);
2418
2419 /* symlink.c */
2420 extern const struct inode_operations ext4_symlink_inode_operations;
2421 extern const struct inode_operations ext4_fast_symlink_inode_operations;
2422
2423 /* block_validity */
2424 extern void ext4_release_system_zone(struct super_block *sb);
2425 extern int ext4_setup_system_zone(struct super_block *sb);
2426 extern int __init ext4_init_system_zone(void);
2427 extern void ext4_exit_system_zone(void);
2428 extern int ext4_data_block_valid(struct ext4_sb_info *sbi,
2429                                  ext4_fsblk_t start_blk,
2430                                  unsigned int count);
2431 extern int ext4_check_blockref(const char *, unsigned int,
2432                                struct inode *, __le32 *, unsigned int);
2433
2434 /* extents.c */
2435 struct ext4_ext_path;
2436 struct ext4_extent;
2437
2438 extern int ext4_ext_tree_init(handle_t *handle, struct inode *);
2439 extern int ext4_ext_writepage_trans_blocks(struct inode *, int);
2440 extern int ext4_ext_index_trans_blocks(struct inode *inode, int nrblocks,
2441                                        int chunk);
2442 extern int ext4_ext_map_blocks(handle_t *handle, struct inode *inode,
2443                                struct ext4_map_blocks *map, int flags);
2444 extern void ext4_ext_truncate(struct inode *);
2445 extern int ext4_ext_punch_hole(struct file *file, loff_t offset,
2446                                 loff_t length);
2447 extern void ext4_ext_init(struct super_block *);
2448 extern void ext4_ext_release(struct super_block *);
2449 extern long ext4_fallocate(struct file *file, int mode, loff_t offset,
2450                           loff_t len);
2451 extern int ext4_convert_unwritten_extents(struct inode *inode, loff_t offset,
2452                           ssize_t len);
2453 extern int ext4_map_blocks(handle_t *handle, struct inode *inode,
2454                            struct ext4_map_blocks *map, int flags);
2455 extern int ext4_ext_calc_metadata_amount(struct inode *inode,
2456                                          ext4_lblk_t lblocks);
2457 extern int ext4_extent_tree_init(handle_t *, struct inode *);
2458 extern int ext4_ext_calc_credits_for_single_extent(struct inode *inode,
2459                                                    int num,
2460                                                    struct ext4_ext_path *path);
2461 extern int ext4_can_extents_be_merged(struct inode *inode,
2462                                       struct ext4_extent *ex1,
2463                                       struct ext4_extent *ex2);
2464 extern int ext4_ext_insert_extent(handle_t *, struct inode *,
2465                                   struct ext4_ext_path *,
2466                                   struct ext4_extent *, int);
2467 extern struct ext4_ext_path *ext4_ext_find_extent(struct inode *, ext4_lblk_t,
2468                                                   struct ext4_ext_path *);
2469 extern void ext4_ext_drop_refs(struct ext4_ext_path *);
2470 extern int ext4_ext_check_inode(struct inode *inode);
2471 extern int ext4_find_delalloc_cluster(struct inode *inode, ext4_lblk_t lblk);
2472 extern int ext4_fiemap(struct inode *inode, struct fiemap_extent_info *fieinfo,
2473                         __u64 start, __u64 len);
2474
2475
2476 /* move_extent.c */
2477 extern int ext4_move_extents(struct file *o_filp, struct file *d_filp,
2478                              __u64 start_orig, __u64 start_donor,
2479                              __u64 len, __u64 *moved_len);
2480
2481 /* page-io.c */
2482 extern int __init ext4_init_pageio(void);
2483 extern void ext4_add_complete_io(ext4_io_end_t *io_end);
2484 extern void ext4_exit_pageio(void);
2485 extern void ext4_ioend_wait(struct inode *);
2486 extern void ext4_free_io_end(ext4_io_end_t *io);
2487 extern ext4_io_end_t *ext4_init_io_end(struct inode *inode, gfp_t flags);
2488 extern void ext4_io_submit(struct ext4_io_submit *io);
2489 extern int ext4_bio_write_page(struct ext4_io_submit *io,
2490                                struct page *page,
2491                                int len,
2492                                struct writeback_control *wbc);
2493
2494 /* mmp.c */
2495 extern int ext4_multi_mount_protect(struct super_block *, ext4_fsblk_t);
2496 extern void ext4_mmp_csum_set(struct super_block *sb, struct mmp_struct *mmp);
2497 extern int ext4_mmp_csum_verify(struct super_block *sb,
2498                                 struct mmp_struct *mmp);
2499
2500 /* BH_Uninit flag: blocks are allocated but uninitialized on disk */
2501 enum ext4_state_bits {
2502         BH_Uninit       /* blocks are allocated but uninitialized on disk */
2503           = BH_JBDPrivateStart,
2504         BH_AllocFromCluster,    /* allocated blocks were part of already
2505                                  * allocated cluster. Note that this flag will
2506                                  * never, ever appear in a buffer_head's state
2507                                  * flag. See EXT4_MAP_FROM_CLUSTER to see where
2508                                  * this is used. */
2509 };
2510
2511 BUFFER_FNS(Uninit, uninit)
2512 TAS_BUFFER_FNS(Uninit, uninit)
2513
2514 /*
2515  * Add new method to test wether block and inode bitmaps are properly
2516  * initialized. With uninit_bg reading the block from disk is not enough
2517  * to mark the bitmap uptodate. We need to also zero-out the bitmap
2518  */
2519 #define BH_BITMAP_UPTODATE BH_JBDPrivateStart
2520
2521 static inline int bitmap_uptodate(struct buffer_head *bh)
2522 {
2523         return (buffer_uptodate(bh) &&
2524                         test_bit(BH_BITMAP_UPTODATE, &(bh)->b_state));
2525 }
2526 static inline void set_bitmap_uptodate(struct buffer_head *bh)
2527 {
2528         set_bit(BH_BITMAP_UPTODATE, &(bh)->b_state);
2529 }
2530
2531 /*
2532  * Disable DIO read nolock optimization, so new dioreaders will be forced
2533  * to grab i_mutex
2534  */
2535 static inline void ext4_inode_block_unlocked_dio(struct inode *inode)
2536 {
2537         ext4_set_inode_state(inode, EXT4_STATE_DIOREAD_LOCK);
2538         smp_mb();
2539 }
2540 static inline void ext4_inode_resume_unlocked_dio(struct inode *inode)
2541 {
2542         smp_mb();
2543         ext4_clear_inode_state(inode, EXT4_STATE_DIOREAD_LOCK);
2544 }
2545
2546 #define in_range(b, first, len) ((b) >= (first) && (b) <= (first) + (len) - 1)
2547
2548 /* For ioend & aio unwritten conversion wait queues */
2549 #define EXT4_WQ_HASH_SZ         37
2550 #define ext4_ioend_wq(v)   (&ext4__ioend_wq[((unsigned long)(v)) %\
2551                                             EXT4_WQ_HASH_SZ])
2552 #define ext4_aio_mutex(v)  (&ext4__aio_mutex[((unsigned long)(v)) %\
2553                                              EXT4_WQ_HASH_SZ])
2554 extern wait_queue_head_t ext4__ioend_wq[EXT4_WQ_HASH_SZ];
2555 extern struct mutex ext4__aio_mutex[EXT4_WQ_HASH_SZ];
2556
2557 #define EXT4_RESIZING   0
2558 extern int ext4_resize_begin(struct super_block *sb);
2559 extern void ext4_resize_end(struct super_block *sb);
2560
2561 #endif  /* __KERNEL__ */
2562
2563 #endif  /* _EXT4_H */