fs/ext4/ext4.h

   1 /*
   2  *  ext4.h
   3  *
   4  * Copyright (C) 1992, 1993, 1994, 1995
   5  * Remy Card (card@masi.ibp.fr)
   6  * Laboratoire MASI - Institut Blaise Pascal
   7  * Universite Pierre et Marie Curie (Paris VI)
   8  *
   9  *  from
  10  *
  11  *  linux/include/linux/minix_fs.h
  12  *
  13  *  Copyright (C) 1991, 1992  Linus Torvalds
  14  */
  15
  16 #ifndef _EXT4_H
  17 #define _EXT4_H
  18
  19 #include <linux/types.h>
  20 #include <linux/blkdev.h>
  21 #include <linux/magic.h>
  22 #include <linux/jbd2.h>
  23 #include <linux/quota.h>
  24 #include <linux/rwsem.h>
  25 #include <linux/rbtree.h>
  26 #include <linux/seqlock.h>
  27 #include <linux/mutex.h>
  28 #include <linux/timer.h>
  29 #include <linux/wait.h>
  30 #include <linux/blockgroup_lock.h>
  31 #include <linux/percpu_counter.h>
  32 #include <crypto/hash.h>
  33 #ifdef __KERNEL__
  34 #include <linux/compat.h>
  35 #endif
  36
  37 /*
  38  * The fourth extended filesystem constants/structures
  39  */
  40
  41 /*
  42  * Define EXT4FS_DEBUG to produce debug messages
  43  */
  44 #undef EXT4FS_DEBUG
  45
  46 /*
  47  * Debug code
  48  */
  49 #ifdef EXT4FS_DEBUG
  50 #define ext4_debug(f, a...)                                             \
  51         do {                                                            \
  52                 printk(KERN_DEBUG "EXT4-fs DEBUG (%s, %d): %s:",        \
  53                         __FILE__, __LINE__, __func__);                  \
  54                 printk(KERN_DEBUG f, ## a);                             \
  55         } while (0)
  56 #else
  57 #define ext4_debug(fmt, ...)    no_printk(fmt, ##__VA_ARGS__)
  58 #endif
  59
  60 #define EXT4_ERROR_INODE(inode, fmt, a...) \
  61         ext4_error_inode((inode), __func__, __LINE__, 0, (fmt), ## a)
  62
  63 #define EXT4_ERROR_INODE_BLOCK(inode, block, fmt, a...)                 \
  64         ext4_error_inode((inode), __func__, __LINE__, (block), (fmt), ## a)
  65
  66 #define EXT4_ERROR_FILE(file, block, fmt, a...)                         \
  67         ext4_error_file((file), __func__, __LINE__, (block), (fmt), ## a)
  68
  69 /* data type for block offset of block group */
  70 typedef int ext4_grpblk_t;
  71
  72 /* data type for filesystem-wide blocks number */
  73 typedef unsigned long long ext4_fsblk_t;
  74
  75 /* data type for file logical block number */
  76 typedef __u32 ext4_lblk_t;
  77
  78 /* data type for block group number */
  79 typedef unsigned int ext4_group_t;
  80
  81 /*
  82  * Flags used in mballoc's allocation_context flags field.
  83  *
  84  * Also used to show what's going on for debugging purposes when the
  85  * flag field is exported via the traceport interface
  86  */
  87
  88 /* prefer goal again. length */
  89 #define EXT4_MB_HINT_MERGE              0x0001
  90 /* blocks already reserved */
  91 #define EXT4_MB_HINT_RESERVED           0x0002
  92 /* metadata is being allocated */
  93 #define EXT4_MB_HINT_METADATA           0x0004
  94 /* first blocks in the file */
  95 #define EXT4_MB_HINT_FIRST              0x0008
  96 /* search for the best chunk */
  97 #define EXT4_MB_HINT_BEST               0x0010
  98 /* data is being allocated */
  99 #define EXT4_MB_HINT_DATA               0x0020
 100 /* don't preallocate (for tails) */
 101 #define EXT4_MB_HINT_NOPREALLOC         0x0040
 102 /* allocate for locality group */
 103 #define EXT4_MB_HINT_GROUP_ALLOC        0x0080
 104 /* allocate goal blocks or none */
 105 #define EXT4_MB_HINT_GOAL_ONLY          0x0100
 106 /* goal is meaningful */
 107 #define EXT4_MB_HINT_TRY_GOAL           0x0200
 108 /* blocks already pre-reserved by delayed allocation */
 109 #define EXT4_MB_DELALLOC_RESERVED       0x0400
 110 /* We are doing stream allocation */
 111 #define EXT4_MB_STREAM_ALLOC            0x0800
 112 /* Use reserved root blocks if needed */
 113 #define EXT4_MB_USE_ROOT_BLOCKS         0x1000
 114
 115 struct ext4_allocation_request {
 116         /* target inode for block we're allocating */
 117         struct inode *inode;
 118         /* how many blocks we want to allocate */
 119         unsigned int len;
 120         /* logical block in target inode */
 121         ext4_lblk_t logical;
 122         /* the closest logical allocated block to the left */
 123         ext4_lblk_t lleft;
 124         /* the closest logical allocated block to the right */
 125         ext4_lblk_t lright;
 126         /* phys. target (a hint) */
 127         ext4_fsblk_t goal;
 128         /* phys. block for the closest logical allocated block to the left */
 129         ext4_fsblk_t pleft;
 130         /* phys. block for the closest logical allocated block to the right */
 131         ext4_fsblk_t pright;
 132         /* flags. see above EXT4_MB_HINT_* */
 133         unsigned int flags;
 134 };
 135
 136 /*
 137  * Logical to physical block mapping, used by ext4_map_blocks()
 138  *
 139  * This structure is used to pass requests into ext4_map_blocks() as
 140  * well as to store the information returned by ext4_map_blocks().  It
 141  * takes less room on the stack than a struct buffer_head.
 142  */
 143 #define EXT4_MAP_NEW            (1 << BH_New)
 144 #define EXT4_MAP_MAPPED         (1 << BH_Mapped)
 145 #define EXT4_MAP_UNWRITTEN      (1 << BH_Unwritten)
 146 #define EXT4_MAP_BOUNDARY       (1 << BH_Boundary)
 147 #define EXT4_MAP_UNINIT         (1 << BH_Uninit)
 148 /* Sometimes (in the bigalloc case, from ext4_da_get_block_prep) the caller of
 149  * ext4_map_blocks wants to know whether or not the underlying cluster has
 150  * already been accounted for. EXT4_MAP_FROM_CLUSTER conveys to the caller that
 151  * the requested mapping was from previously mapped (or delayed allocated)
 152  * cluster. We use BH_AllocFromCluster only for this flag. BH_AllocFromCluster
 153  * should never appear on buffer_head's state flags.
 154  */
 155 #define EXT4_MAP_FROM_CLUSTER   (1 << BH_AllocFromCluster)
 156 #define EXT4_MAP_FLAGS          (EXT4_MAP_NEW | EXT4_MAP_MAPPED |\
 157                                  EXT4_MAP_UNWRITTEN | EXT4_MAP_BOUNDARY |\
 158                                  EXT4_MAP_UNINIT | EXT4_MAP_FROM_CLUSTER)
 159
 160 struct ext4_map_blocks {
 161         ext4_fsblk_t m_pblk;
 162         ext4_lblk_t m_lblk;
 163         unsigned int m_len;
 164         unsigned int m_flags;
 165 };
 166
 167 /*
 168  * For delayed allocation tracking
 169  */
 170 struct mpage_da_data {
 171         struct inode *inode;
 172         sector_t b_blocknr;             /* start block number of extent */
 173         size_t b_size;                  /* size of extent */
 174         unsigned long b_state;          /* state of the extent */
 175         unsigned long first_page, next_page;    /* extent of pages */
 176         struct writeback_control *wbc;
 177         int io_done;
 178         int pages_written;
 179         int retval;
 180 };
 181
 182 /*
 183  * Flags for ext4_io_end->flags
 184  */
 185 #define EXT4_IO_END_UNWRITTEN   0x0001
 186 #define EXT4_IO_END_ERROR       0x0002
 187 #define EXT4_IO_END_QUEUED      0x0004
 188 #define EXT4_IO_END_DIRECT      0x0008
 189 #define EXT4_IO_END_IN_FSYNC    0x0010
 190
 191 struct ext4_io_page {
 192         struct page     *p_page;
 193         atomic_t        p_count;
 194 };
 195
 196 #define MAX_IO_PAGES 128
 197
 198 /*
 199  * For converting uninitialized extents on a work queue.
 200  *
 201  * 'page' is only used from the writepage() path; 'pages' is only used for
 202  * buffered writes; they are used to keep page references until conversion
 203  * takes place.  For AIO/DIO, neither field is filled in.
 204  */
 205 typedef struct ext4_io_end {
 206         struct list_head        list;           /* per-file finished IO list */
 207         struct inode            *inode;         /* file being written to */
 208         unsigned int            flag;           /* unwritten or not */
 209         struct page             *page;          /* for writepage() path */
 210         loff_t                  offset;         /* offset in the file */
 211         ssize_t                 size;           /* size of the extent */
 212         struct work_struct      work;           /* data work queue */
 213         struct kiocb            *iocb;          /* iocb struct for AIO */
 214         int                     result;         /* error value for AIO */
 215         int                     num_io_pages;   /* for writepages() */
 216         struct ext4_io_page     *pages[MAX_IO_PAGES]; /* for writepages() */
 217 } ext4_io_end_t;
 218
 219 struct ext4_io_submit {
 220         int                     io_op;
 221         struct bio              *io_bio;
 222         ext4_io_end_t           *io_end;
 223         struct ext4_io_page     *io_page;
 224         sector_t                io_next_block;
 225 };
 226
 227 /*
 228  * Special inodes numbers
 229  */
 230 #define EXT4_BAD_INO             1      /* Bad blocks inode */
 231 #define EXT4_ROOT_INO            2      /* Root inode */
 232 #define EXT4_USR_QUOTA_INO       3      /* User quota inode */
 233 #define EXT4_GRP_QUOTA_INO       4      /* Group quota inode */
 234 #define EXT4_BOOT_LOADER_INO     5      /* Boot loader inode */
 235 #define EXT4_UNDEL_DIR_INO       6      /* Undelete directory inode */
 236 #define EXT4_RESIZE_INO          7      /* Reserved group descriptors inode */
 237 #define EXT4_JOURNAL_INO         8      /* Journal inode */
 238
 239 /* First non-reserved inode for old ext4 filesystems */
 240 #define EXT4_GOOD_OLD_FIRST_INO 11
 241
 242 /*
 243  * Maximal count of links to a file
 244  */
 245 #define EXT4_LINK_MAX           65000
 246
 247 /*
 248  * Macro-instructions used to manage several block sizes
 249  */
 250 #define EXT4_MIN_BLOCK_SIZE             1024
 251 #define EXT4_MAX_BLOCK_SIZE             65536
 252 #define EXT4_MIN_BLOCK_LOG_SIZE         10
 253 #define EXT4_MAX_BLOCK_LOG_SIZE         16
 254 #ifdef __KERNEL__
 255 # define EXT4_BLOCK_SIZE(s)             ((s)->s_blocksize)
 256 #else
 257 # define EXT4_BLOCK_SIZE(s)             (EXT4_MIN_BLOCK_SIZE << (s)->s_log_block_size)
 258 #endif
 259 #define EXT4_ADDR_PER_BLOCK(s)          (EXT4_BLOCK_SIZE(s) / sizeof(__u32))
 260 #define EXT4_CLUSTER_SIZE(s)            (EXT4_BLOCK_SIZE(s) << \
 261                                          EXT4_SB(s)->s_cluster_bits)
 262 #ifdef __KERNEL__
 263 # define EXT4_BLOCK_SIZE_BITS(s)        ((s)->s_blocksize_bits)
 264 # define EXT4_CLUSTER_BITS(s)           (EXT4_SB(s)->s_cluster_bits)
 265 #else
 266 # define EXT4_BLOCK_SIZE_BITS(s)        ((s)->s_log_block_size + 10)
 267 #endif
 268 #ifdef __KERNEL__
 269 #define EXT4_ADDR_PER_BLOCK_BITS(s)     (EXT4_SB(s)->s_addr_per_block_bits)
 270 #define EXT4_INODE_SIZE(s)              (EXT4_SB(s)->s_inode_size)
 271 #define EXT4_FIRST_INO(s)               (EXT4_SB(s)->s_first_ino)
 272 #else
 273 #define EXT4_INODE_SIZE(s)      (((s)->s_rev_level == EXT4_GOOD_OLD_REV) ? \
 274                                  EXT4_GOOD_OLD_INODE_SIZE : \
 275                                  (s)->s_inode_size)
 276 #define EXT4_FIRST_INO(s)       (((s)->s_rev_level == EXT4_GOOD_OLD_REV) ? \
 277                                  EXT4_GOOD_OLD_FIRST_INO : \
 278                                  (s)->s_first_ino)
 279 #endif
 280 #define EXT4_BLOCK_ALIGN(size, blkbits)         ALIGN((size), (1 << (blkbits)))
 281
 282 /* Translate a block number to a cluster number */
 283 #define EXT4_B2C(sbi, blk)      ((blk) >> (sbi)->s_cluster_bits)
 284 /* Translate a cluster number to a block number */
 285 #define EXT4_C2B(sbi, cluster)  ((cluster) << (sbi)->s_cluster_bits)
 286 /* Translate # of blks to # of clusters */
 287 #define EXT4_NUM_B2C(sbi, blks) (((blks) + (sbi)->s_cluster_ratio - 1) >> \
 288                                  (sbi)->s_cluster_bits)
 289
 290 /*
 291  * Structure of a blocks group descriptor
 292  */
 293 struct ext4_group_desc
 294 {
 295         __le32  bg_block_bitmap_lo;     /* Blocks bitmap block */
 296         __le32  bg_inode_bitmap_lo;     /* Inodes bitmap block */
 297         __le32  bg_inode_table_lo;      /* Inodes table block */
 298         __le16  bg_free_blocks_count_lo;/* Free blocks count */
 299         __le16  bg_free_inodes_count_lo;/* Free inodes count */
 300         __le16  bg_used_dirs_count_lo;  /* Directories count */
 301         __le16  bg_flags;               /* EXT4_BG_flags (INODE_UNINIT, etc) */
 302         __le32  bg_exclude_bitmap_lo;   /* Exclude bitmap for snapshots */
 303         __le16  bg_block_bitmap_csum_lo;/* crc32c(s_uuid+grp_num+bbitmap) LE */
 304         __le16  bg_inode_bitmap_csum_lo;/* crc32c(s_uuid+grp_num+ibitmap) LE */
 305         __le16  bg_itable_unused_lo;    /* Unused inodes count */
 306         __le16  bg_checksum;            /* crc16(sb_uuid+group+desc) */
 307         __le32  bg_block_bitmap_hi;     /* Blocks bitmap block MSB */
 308         __le32  bg_inode_bitmap_hi;     /* Inodes bitmap block MSB */
 309         __le32  bg_inode_table_hi;      /* Inodes table block MSB */
 310         __le16  bg_free_blocks_count_hi;/* Free blocks count MSB */
 311         __le16  bg_free_inodes_count_hi;/* Free inodes count MSB */
 312         __le16  bg_used_dirs_count_hi;  /* Directories count MSB */
 313         __le16  bg_itable_unused_hi;    /* Unused inodes count MSB */
 314         __le32  bg_exclude_bitmap_hi;   /* Exclude bitmap block MSB */
 315         __le16  bg_block_bitmap_csum_hi;/* crc32c(s_uuid+grp_num+bbitmap) BE */
 316         __le16  bg_inode_bitmap_csum_hi;/* crc32c(s_uuid+grp_num+ibitmap) BE */
 317         __u32   bg_reserved;
 318 };
 319
 320 #define EXT4_BG_INODE_BITMAP_CSUM_HI_END        \
 321         (offsetof(struct ext4_group_desc, bg_inode_bitmap_csum_hi) + \
 322          sizeof(__le16))
 323 #define EXT4_BG_BLOCK_BITMAP_CSUM_HI_END        \
 324         (offsetof(struct ext4_group_desc, bg_block_bitmap_csum_hi) + \
 325          sizeof(__le16))
 326
 327 /*
 328  * Structure of a flex block group info
 329  */
 330
 331 struct flex_groups {
 332         atomic_t free_inodes;
 333         atomic_t free_clusters;
 334         atomic_t used_dirs;
 335 };
 336
 337 #define EXT4_BG_INODE_UNINIT    0x0001 /* Inode table/bitmap not in use */
 338 #define EXT4_BG_BLOCK_UNINIT    0x0002 /* Block bitmap not in use */
 339 #define EXT4_BG_INODE_ZEROED    0x0004 /* On-disk itable initialized to zero */
 340
 341 /*
 342  * Macro-instructions used to manage group descriptors
 343  */
 344 #define EXT4_MIN_DESC_SIZE              32
 345 #define EXT4_MIN_DESC_SIZE_64BIT        64
 346 #define EXT4_MAX_DESC_SIZE              EXT4_MIN_BLOCK_SIZE
 347 #define EXT4_DESC_SIZE(s)               (EXT4_SB(s)->s_desc_size)
 348 #ifdef __KERNEL__
 349 # define EXT4_BLOCKS_PER_GROUP(s)       (EXT4_SB(s)->s_blocks_per_group)
 350 # define EXT4_CLUSTERS_PER_GROUP(s)     (EXT4_SB(s)->s_clusters_per_group)
 351 # define EXT4_DESC_PER_BLOCK(s)         (EXT4_SB(s)->s_desc_per_block)
 352 # define EXT4_INODES_PER_GROUP(s)       (EXT4_SB(s)->s_inodes_per_group)
 353 # define EXT4_DESC_PER_BLOCK_BITS(s)    (EXT4_SB(s)->s_desc_per_block_bits)
 354 #else
 355 # define EXT4_BLOCKS_PER_GROUP(s)       ((s)->s_blocks_per_group)
 356 # define EXT4_DESC_PER_BLOCK(s)         (EXT4_BLOCK_SIZE(s) / EXT4_DESC_SIZE(s))
 357 # define EXT4_INODES_PER_GROUP(s)       ((s)->s_inodes_per_group)
 358 #endif
 359
 360 /*
 361  * Constants relative to the data blocks
 362  */
 363 #define EXT4_NDIR_BLOCKS                12
 364 #define EXT4_IND_BLOCK                  EXT4_NDIR_BLOCKS
 365 #define EXT4_DIND_BLOCK                 (EXT4_IND_BLOCK + 1)
 366 #define EXT4_TIND_BLOCK                 (EXT4_DIND_BLOCK + 1)
 367 #define EXT4_N_BLOCKS                   (EXT4_TIND_BLOCK + 1)
 368
 369 /*
 370  * Inode flags
 371  */
 372 #define EXT4_SECRM_FL                   0x00000001 /* Secure deletion */
 373 #define EXT4_UNRM_FL                    0x00000002 /* Undelete */
 374 #define EXT4_COMPR_FL                   0x00000004 /* Compress file */
 375 #define EXT4_SYNC_FL                    0x00000008 /* Synchronous updates */
 376 #define EXT4_IMMUTABLE_FL               0x00000010 /* Immutable file */
 377 #define EXT4_APPEND_FL                  0x00000020 /* writes to file may only append */
 378 #define EXT4_NODUMP_FL                  0x00000040 /* do not dump file */
 379 #define EXT4_NOATIME_FL                 0x00000080 /* do not update atime */
 380 /* Reserved for compression usage... */
 381 #define EXT4_DIRTY_FL                   0x00000100
 382 #define EXT4_COMPRBLK_FL                0x00000200 /* One or more compressed clusters */
 383 #define EXT4_NOCOMPR_FL                 0x00000400 /* Don't compress */
 384 #define EXT4_ECOMPR_FL                  0x00000800 /* Compression error */
 385 /* End compression flags --- maybe not all used */
 386 #define EXT4_INDEX_FL                   0x00001000 /* hash-indexed directory */
 387 #define EXT4_IMAGIC_FL                  0x00002000 /* AFS directory */
 388 #define EXT4_JOURNAL_DATA_FL            0x00004000 /* file data should be journaled */
 389 #define EXT4_NOTAIL_FL                  0x00008000 /* file tail should not be merged */
 390 #define EXT4_DIRSYNC_FL                 0x00010000 /* dirsync behaviour (directories only) */
 391 #define EXT4_TOPDIR_FL                  0x00020000 /* Top of directory hierarchies*/
 392 #define EXT4_HUGE_FILE_FL               0x00040000 /* Set to each huge file */
 393 #define EXT4_EXTENTS_FL                 0x00080000 /* Inode uses extents */
 394 #define EXT4_EA_INODE_FL                0x00200000 /* Inode used for large EA */
 395 #define EXT4_EOFBLOCKS_FL               0x00400000 /* Blocks allocated beyond EOF */
 396 #define EXT4_RESERVED_FL                0x80000000 /* reserved for ext4 lib */
 397
 398 #define EXT4_FL_USER_VISIBLE            0x004BDFFF /* User visible flags */
 399 #define EXT4_FL_USER_MODIFIABLE         0x004B80FF /* User modifiable flags */
 400
 401 /* Flags that should be inherited by new inodes from their parent. */
 402 #define EXT4_FL_INHERITED (EXT4_SECRM_FL | EXT4_UNRM_FL | EXT4_COMPR_FL |\
 403                            EXT4_SYNC_FL | EXT4_NODUMP_FL | EXT4_NOATIME_FL |\
 404                            EXT4_NOCOMPR_FL | EXT4_JOURNAL_DATA_FL |\
 405                            EXT4_NOTAIL_FL | EXT4_DIRSYNC_FL)
 406
 407 /* Flags that are appropriate for regular files (all but dir-specific ones). */
 408 #define EXT4_REG_FLMASK (~(EXT4_DIRSYNC_FL | EXT4_TOPDIR_FL))
 409
 410 /* Flags that are appropriate for non-directories/regular files. */
 411 #define EXT4_OTHER_FLMASK (EXT4_NODUMP_FL | EXT4_NOATIME_FL)
 412
 413 /* Mask out flags that are inappropriate for the given type of inode. */
 414 static inline __u32 ext4_mask_flags(umode_t mode, __u32 flags)
 415 {
 416         if (S_ISDIR(mode))
 417                 return flags;
 418         else if (S_ISREG(mode))
 419                 return flags & EXT4_REG_FLMASK;
 420         else
 421                 return flags & EXT4_OTHER_FLMASK;
 422 }
 423
 424 /*
 425  * Inode flags used for atomic set/get
 426  */
 427 enum {
 428         EXT4_INODE_SECRM        = 0,    /* Secure deletion */
 429         EXT4_INODE_UNRM         = 1,    /* Undelete */
 430         EXT4_INODE_COMPR        = 2,    /* Compress file */
 431         EXT4_INODE_SYNC         = 3,    /* Synchronous updates */
 432         EXT4_INODE_IMMUTABLE    = 4,    /* Immutable file */
 433         EXT4_INODE_APPEND       = 5,    /* writes to file may only append */
 434         EXT4_INODE_NODUMP       = 6,    /* do not dump file */
 435         EXT4_INODE_NOATIME      = 7,    /* do not update atime */
 436 /* Reserved for compression usage... */
 437         EXT4_INODE_DIRTY        = 8,
 438         EXT4_INODE_COMPRBLK     = 9,    /* One or more compressed clusters */
 439         EXT4_INODE_NOCOMPR      = 10,   /* Don't compress */
 440         EXT4_INODE_ECOMPR       = 11,   /* Compression error */
 441 /* End compression flags --- maybe not all used */
 442         EXT4_INODE_INDEX        = 12,   /* hash-indexed directory */
 443         EXT4_INODE_IMAGIC       = 13,   /* AFS directory */
 444         EXT4_INODE_JOURNAL_DATA = 14,   /* file data should be journaled */
 445         EXT4_INODE_NOTAIL       = 15,   /* file tail should not be merged */
 446         EXT4_INODE_DIRSYNC      = 16,   /* dirsync behaviour (directories only) */
 447         EXT4_INODE_TOPDIR       = 17,   /* Top of directory hierarchies*/
 448         EXT4_INODE_HUGE_FILE    = 18,   /* Set to each huge file */
 449         EXT4_INODE_EXTENTS      = 19,   /* Inode uses extents */
 450         EXT4_INODE_EA_INODE     = 21,   /* Inode used for large EA */
 451         EXT4_INODE_EOFBLOCKS    = 22,   /* Blocks allocated beyond EOF */
 452         EXT4_INODE_RESERVED     = 31,   /* reserved for ext4 lib */
 453 };
 454
 455 #define TEST_FLAG_VALUE(FLAG) (EXT4_##FLAG##_FL == (1 << EXT4_INODE_##FLAG))
 456 #define CHECK_FLAG_VALUE(FLAG) if (!TEST_FLAG_VALUE(FLAG)) { \
 457         printk(KERN_EMERG "EXT4 flag fail: " #FLAG ": %d %d\n", \
 458                 EXT4_##FLAG##_FL, EXT4_INODE_##FLAG); BUG_ON(1); }
 459
 460 /*
 461  * Since it's pretty easy to mix up bit numbers and hex values, and we
 462  * can't do a compile-time test for ENUM values, we use a run-time
 463  * test to make sure that EXT4_XXX_FL is consistent with respect to
 464  * EXT4_INODE_XXX.  If all is well the printk and BUG_ON will all drop
 465  * out so it won't cost any extra space in the compiled kernel image.
 466  * But it's important that these values are the same, since we are
 467  * using EXT4_INODE_XXX to test for the flag values, but EXT4_XX_FL
 468  * must be consistent with the values of FS_XXX_FL defined in
 469  * include/linux/fs.h and the on-disk values found in ext2, ext3, and
 470  * ext4 filesystems, and of course the values defined in e2fsprogs.
 471  *
 472  * It's not paranoia if the Murphy's Law really *is* out to get you.  :-)
 473  */
 474 static inline void ext4_check_flag_values(void)
 475 {
 476         CHECK_FLAG_VALUE(SECRM);
 477         CHECK_FLAG_VALUE(UNRM);
 478         CHECK_FLAG_VALUE(COMPR);
 479         CHECK_FLAG_VALUE(SYNC);
 480         CHECK_FLAG_VALUE(IMMUTABLE);
 481         CHECK_FLAG_VALUE(APPEND);
 482         CHECK_FLAG_VALUE(NODUMP);
 483         CHECK_FLAG_VALUE(NOATIME);
 484         CHECK_FLAG_VALUE(DIRTY);
 485         CHECK_FLAG_VALUE(COMPRBLK);
 486         CHECK_FLAG_VALUE(NOCOMPR);
 487         CHECK_FLAG_VALUE(ECOMPR);
 488         CHECK_FLAG_VALUE(INDEX);
 489         CHECK_FLAG_VALUE(IMAGIC);
 490         CHECK_FLAG_VALUE(JOURNAL_DATA);
 491         CHECK_FLAG_VALUE(NOTAIL);
 492         CHECK_FLAG_VALUE(DIRSYNC);
 493         CHECK_FLAG_VALUE(TOPDIR);
 494         CHECK_FLAG_VALUE(HUGE_FILE);
 495         CHECK_FLAG_VALUE(EXTENTS);
 496         CHECK_FLAG_VALUE(EA_INODE);
 497         CHECK_FLAG_VALUE(EOFBLOCKS);
 498         CHECK_FLAG_VALUE(RESERVED);
 499 }
 500
 501 /* Used to pass group descriptor data when online resize is done */
 502 struct ext4_new_group_input {
 503         __u32 group;            /* Group number for this data */
 504         __u64 block_bitmap;     /* Absolute block number of block bitmap */
 505         __u64 inode_bitmap;     /* Absolute block number of inode bitmap */
 506         __u64 inode_table;      /* Absolute block number of inode table start */
 507         __u32 blocks_count;     /* Total number of blocks in this group */
 508         __u16 reserved_blocks;  /* Number of reserved blocks in this group */
 509         __u16 unused;
 510 };
 511
 512 #if defined(__KERNEL__) && defined(CONFIG_COMPAT)
 513 struct compat_ext4_new_group_input {
 514         u32 group;
 515         compat_u64 block_bitmap;
 516         compat_u64 inode_bitmap;
 517         compat_u64 inode_table;
 518         u32 blocks_count;
 519         u16 reserved_blocks;
 520         u16 unused;
 521 };
 522 #endif
 523
 524 /* The struct ext4_new_group_input in kernel space, with free_blocks_count */
 525 struct ext4_new_group_data {
 526         __u32 group;
 527         __u64 block_bitmap;
 528         __u64 inode_bitmap;
 529         __u64 inode_table;
 530         __u32 blocks_count;
 531         __u16 reserved_blocks;
 532         __u16 unused;
 533         __u32 free_blocks_count;
 534 };
 535
 536 /* Indexes used to index group tables in ext4_new_group_data */
 537 enum {
 538         BLOCK_BITMAP = 0,       /* block bitmap */
 539         INODE_BITMAP,           /* inode bitmap */
 540         INODE_TABLE,            /* inode tables */
 541         GROUP_TABLE_COUNT,
 542 };
 543
 544 /*
 545  * Flags used by ext4_map_blocks()
 546  */
 547         /* Allocate any needed blocks and/or convert an unitialized
 548            extent to be an initialized ext4 */
 549 #define EXT4_GET_BLOCKS_CREATE                  0x0001
 550         /* Request the creation of an unitialized extent */
 551 #define EXT4_GET_BLOCKS_UNINIT_EXT              0x0002
 552 #define EXT4_GET_BLOCKS_CREATE_UNINIT_EXT       (EXT4_GET_BLOCKS_UNINIT_EXT|\
 553                                                  EXT4_GET_BLOCKS_CREATE)
 554         /* Caller is from the delayed allocation writeout path,
 555            so set the magic i_delalloc_reserve_flag after taking the
 556            inode allocation semaphore for */
 557 #define EXT4_GET_BLOCKS_DELALLOC_RESERVE        0x0004
 558         /* caller is from the direct IO path, request to creation of an
 559         unitialized extents if not allocated, split the uninitialized
 560         extent if blocks has been preallocated already*/
 561 #define EXT4_GET_BLOCKS_PRE_IO                  0x0008
 562 #define EXT4_GET_BLOCKS_CONVERT                 0x0010
 563 #define EXT4_GET_BLOCKS_IO_CREATE_EXT           (EXT4_GET_BLOCKS_PRE_IO|\
 564                                          EXT4_GET_BLOCKS_CREATE_UNINIT_EXT)
 565         /* Convert extent to initialized after IO complete */
 566 #define EXT4_GET_BLOCKS_IO_CONVERT_EXT          (EXT4_GET_BLOCKS_CONVERT|\
 567                                          EXT4_GET_BLOCKS_CREATE_UNINIT_EXT)
 568         /* Punch out blocks of an extent */
 569 #define EXT4_GET_BLOCKS_PUNCH_OUT_EXT           0x0020
 570         /* Don't normalize allocation size (used for fallocate) */
 571 #define EXT4_GET_BLOCKS_NO_NORMALIZE            0x0040
 572         /* Request will not result in inode size update (user for fallocate) */
 573 #define EXT4_GET_BLOCKS_KEEP_SIZE               0x0080
 574
 575 /*
 576  * Flags used by ext4_free_blocks
 577  */
 578 #define EXT4_FREE_BLOCKS_METADATA       0x0001
 579 #define EXT4_FREE_BLOCKS_FORGET         0x0002
 580 #define EXT4_FREE_BLOCKS_VALIDATED      0x0004
 581 #define EXT4_FREE_BLOCKS_NO_QUOT_UPDATE 0x0008
 582 #define EXT4_FREE_BLOCKS_NOFREE_FIRST_CLUSTER   0x0010
 583 #define EXT4_FREE_BLOCKS_NOFREE_LAST_CLUSTER    0x0020
 584
 585 /*
 586  * Flags used by ext4_discard_partial_page_buffers
 587  */
 588 #define EXT4_DISCARD_PARTIAL_PG_ZERO_UNMAPPED   0x0001
 589
 590 /*
 591  * ioctl commands
 592  */
 593 #define EXT4_IOC_GETFLAGS               FS_IOC_GETFLAGS
 594 #define EXT4_IOC_SETFLAGS               FS_IOC_SETFLAGS
 595 #define EXT4_IOC_GETVERSION             _IOR('f', 3, long)
 596 #define EXT4_IOC_SETVERSION             _IOW('f', 4, long)
 597 #define EXT4_IOC_GETVERSION_OLD         FS_IOC_GETVERSION
 598 #define EXT4_IOC_SETVERSION_OLD         FS_IOC_SETVERSION
 599 #define EXT4_IOC_GETRSVSZ               _IOR('f', 5, long)
 600 #define EXT4_IOC_SETRSVSZ               _IOW('f', 6, long)
 601 #define EXT4_IOC_GROUP_EXTEND           _IOW('f', 7, unsigned long)
 602 #define EXT4_IOC_GROUP_ADD              _IOW('f', 8, struct ext4_new_group_input)
 603 #define EXT4_IOC_MIGRATE                _IO('f', 9)
 604  /* note ioctl 10 reserved for an early version of the FIEMAP ioctl */
 605  /* note ioctl 11 reserved for filesystem-independent FIEMAP ioctl */
 606 #define EXT4_IOC_ALLOC_DA_BLKS          _IO('f', 12)
 607 #define EXT4_IOC_MOVE_EXT               _IOWR('f', 15, struct move_extent)
 608 #define EXT4_IOC_RESIZE_FS              _IOW('f', 16, __u64)
 609
 610 #if defined(__KERNEL__) && defined(CONFIG_COMPAT)
 611 /*
 612  * ioctl commands in 32 bit emulation
 613  */
 614 #define EXT4_IOC32_GETFLAGS             FS_IOC32_GETFLAGS
 615 #define EXT4_IOC32_SETFLAGS             FS_IOC32_SETFLAGS
 616 #define EXT4_IOC32_GETVERSION           _IOR('f', 3, int)
 617 #define EXT4_IOC32_SETVERSION           _IOW('f', 4, int)
 618 #define EXT4_IOC32_GETRSVSZ             _IOR('f', 5, int)
 619 #define EXT4_IOC32_SETRSVSZ             _IOW('f', 6, int)
 620 #define EXT4_IOC32_GROUP_EXTEND         _IOW('f', 7, unsigned int)
 621 #define EXT4_IOC32_GROUP_ADD            _IOW('f', 8, struct compat_ext4_new_group_input)
 622 #define EXT4_IOC32_GETVERSION_OLD       FS_IOC32_GETVERSION
 623 #define EXT4_IOC32_SETVERSION_OLD       FS_IOC32_SETVERSION
 624 #endif
 625
 626 /* Max physical block we can address w/o extents */
 627 #define EXT4_MAX_BLOCK_FILE_PHYS        0xFFFFFFFF
 628
 629 /*
 630  * Structure of an inode on the disk
 631  */
 632 struct ext4_inode {
 633         __le16  i_mode;         /* File mode */
 634         __le16  i_uid;          /* Low 16 bits of Owner Uid */
 635         __le32  i_size_lo;      /* Size in bytes */
 636         __le32  i_atime;        /* Access time */
 637         __le32  i_ctime;        /* Inode Change time */
 638         __le32  i_mtime;        /* Modification time */
 639         __le32  i_dtime;        /* Deletion Time */
 640         __le16  i_gid;          /* Low 16 bits of Group Id */
 641         __le16  i_links_count;  /* Links count */
 642         __le32  i_blocks_lo;    /* Blocks count */
 643         __le32  i_flags;        /* File flags */
 644         union {
 645                 struct {
 646                         __le32  l_i_version;
 647                 } linux1;
 648                 struct {
 649                         __u32  h_i_translator;
 650                 } hurd1;
 651                 struct {
 652                         __u32  m_i_reserved1;
 653                 } masix1;
 654         } osd1;                         /* OS dependent 1 */
 655         __le32  i_block[EXT4_N_BLOCKS];/* Pointers to blocks */
 656         __le32  i_generation;   /* File version (for NFS) */
 657         __le32  i_file_acl_lo;  /* File ACL */
 658         __le32  i_size_high;
 659         __le32  i_obso_faddr;   /* Obsoleted fragment address */
 660         union {
 661                 struct {
 662                         __le16  l_i_blocks_high; /* were l_i_reserved1 */
 663                         __le16  l_i_file_acl_high;
 664                         __le16  l_i_uid_high;   /* these 2 fields */
 665                         __le16  l_i_gid_high;   /* were reserved2[0] */
 666                         __le16  l_i_checksum_lo;/* crc32c(uuid+inum+inode) LE */
 667                         __le16  l_i_reserved;
 668                 } linux2;
 669                 struct {
 670                         __le16  h_i_reserved1;  /* Obsoleted fragment number/size which are removed in ext4 */
 671                         __u16   h_i_mode_high;
 672                         __u16   h_i_uid_high;
 673                         __u16   h_i_gid_high;
 674                         __u32   h_i_author;
 675                 } hurd2;
 676                 struct {
 677                         __le16  h_i_reserved1;  /* Obsoleted fragment number/size which are removed in ext4 */
 678                         __le16  m_i_file_acl_high;
 679                         __u32   m_i_reserved2[2];
 680                 } masix2;
 681         } osd2;                         /* OS dependent 2 */
 682         __le16  i_extra_isize;
 683         __le16  i_checksum_hi;  /* crc32c(uuid+inum+inode) BE */
 684         __le32  i_ctime_extra;  /* extra Change time      (nsec << 2 | epoch) */
 685         __le32  i_mtime_extra;  /* extra Modification time(nsec << 2 | epoch) */
 686         __le32  i_atime_extra;  /* extra Access time      (nsec << 2 | epoch) */
 687         __le32  i_crtime;       /* File Creation time */
 688         __le32  i_crtime_extra; /* extra FileCreationtime (nsec << 2 | epoch) */
 689         __le32  i_version_hi;   /* high 32 bits for 64-bit version */
 690 };
 691
 692 struct move_extent {
 693         __u32 reserved;         /* should be zero */
 694         __u32 donor_fd;         /* donor file descriptor */
 695         __u64 orig_start;       /* logical start offset in block for orig */
 696         __u64 donor_start;      /* logical start offset in block for donor */
 697         __u64 len;              /* block length to be moved */
 698         __u64 moved_len;        /* moved block length */
 699 };
 700
 701 #define EXT4_EPOCH_BITS 2
 702 #define EXT4_EPOCH_MASK ((1 << EXT4_EPOCH_BITS) - 1)
 703 #define EXT4_NSEC_MASK  (~0UL << EXT4_EPOCH_BITS)
 704
 705 /*
 706  * Extended fields will fit into an inode if the filesystem was formatted
 707  * with large inodes (-I 256 or larger) and there are not currently any EAs
 708  * consuming all of the available space. For new inodes we always reserve
 709  * enough space for the kernel's known extended fields, but for inodes
 710  * created with an old kernel this might not have been the case. None of
 711  * the extended inode fields is critical for correct filesystem operation.
 712  * This macro checks if a certain field fits in the inode. Note that
 713  * inode-size = GOOD_OLD_INODE_SIZE + i_extra_isize
 714  */
 715 #define EXT4_FITS_IN_INODE(ext4_inode, einode, field)   \
 716         ((offsetof(typeof(*ext4_inode), field) +        \
 717           sizeof((ext4_inode)->field))                  \
 718         <= (EXT4_GOOD_OLD_INODE_SIZE +                  \
 719             (einode)->i_extra_isize))                   \
 720
 721 static inline __le32 ext4_encode_extra_time(struct timespec *time)
 722 {
 723        return cpu_to_le32((sizeof(time->tv_sec) > 4 ?
 724                            (time->tv_sec >> 32) & EXT4_EPOCH_MASK : 0) |
 725                           ((time->tv_nsec << EXT4_EPOCH_BITS) & EXT4_NSEC_MASK));
 726 }
 727
 728 static inline void ext4_decode_extra_time(struct timespec *time, __le32 extra)
 729 {
 730        if (sizeof(time->tv_sec) > 4)
 731                time->tv_sec |= (__u64)(le32_to_cpu(extra) & EXT4_EPOCH_MASK)
 732                                << 32;
 733        time->tv_nsec = (le32_to_cpu(extra) & EXT4_NSEC_MASK) >> EXT4_EPOCH_BITS;
 734 }
 735
 736 #define EXT4_INODE_SET_XTIME(xtime, inode, raw_inode)                          \
 737 do {                                                                           \
 738         (raw_inode)->xtime = cpu_to_le32((inode)->xtime.tv_sec);               \
 739         if (EXT4_FITS_IN_INODE(raw_inode, EXT4_I(inode), xtime ## _extra))     \
 740                 (raw_inode)->xtime ## _extra =                                 \
 741                                 ext4_encode_extra_time(&(inode)->xtime);       \
 742 } while (0)
 743
 744 #define EXT4_EINODE_SET_XTIME(xtime, einode, raw_inode)                        \
 745 do {                                                                           \
 746         if (EXT4_FITS_IN_INODE(raw_inode, einode, xtime))                      \
 747                 (raw_inode)->xtime = cpu_to_le32((einode)->xtime.tv_sec);      \
 748         if (EXT4_FITS_IN_INODE(raw_inode, einode, xtime ## _extra))            \
 749                 (raw_inode)->xtime ## _extra =                                 \
 750                                 ext4_encode_extra_time(&(einode)->xtime);      \
 751 } while (0)
 752
 753 #define EXT4_INODE_GET_XTIME(xtime, inode, raw_inode)                          \
 754 do {                                                                           \
 755         (inode)->xtime.tv_sec = (signed)le32_to_cpu((raw_inode)->xtime);       \
 756         if (EXT4_FITS_IN_INODE(raw_inode, EXT4_I(inode), xtime ## _extra))     \
 757                 ext4_decode_extra_time(&(inode)->xtime,                        \
 758                                        raw_inode->xtime ## _extra);            \
 759         else                                                                   \
 760                 (inode)->xtime.tv_nsec = 0;                                    \
 761 } while (0)
 762
 763 #define EXT4_EINODE_GET_XTIME(xtime, einode, raw_inode)                        \
 764 do {                                                                           \
 765         if (EXT4_FITS_IN_INODE(raw_inode, einode, xtime))                      \
 766                 (einode)->xtime.tv_sec =                                       \
 767                         (signed)le32_to_cpu((raw_inode)->xtime);               \
 768         if (EXT4_FITS_IN_INODE(raw_inode, einode, xtime ## _extra))            \
 769                 ext4_decode_extra_time(&(einode)->xtime,                       \
 770                                        raw_inode->xtime ## _extra);            \
 771         else                                                                   \
 772                 (einode)->xtime.tv_nsec = 0;                                   \
 773 } while (0)
 774
 775 #define i_disk_version osd1.linux1.l_i_version
 776
 777 #if defined(__KERNEL__) || defined(__linux__)
 778 #define i_reserved1     osd1.linux1.l_i_reserved1
 779 #define i_file_acl_high osd2.linux2.l_i_file_acl_high
 780 #define i_blocks_high   osd2.linux2.l_i_blocks_high
 781 #define i_uid_low       i_uid
 782 #define i_gid_low       i_gid
 783 #define i_uid_high      osd2.linux2.l_i_uid_high
 784 #define i_gid_high      osd2.linux2.l_i_gid_high
 785 #define i_checksum_lo   osd2.linux2.l_i_checksum_lo
 786
 787 #elif defined(__GNU__)
 788
 789 #define i_translator    osd1.hurd1.h_i_translator
 790 #define i_uid_high      osd2.hurd2.h_i_uid_high
 791 #define i_gid_high      osd2.hurd2.h_i_gid_high
 792 #define i_author        osd2.hurd2.h_i_author
 793
 794 #elif defined(__masix__)
 795
 796 #define i_reserved1     osd1.masix1.m_i_reserved1
 797 #define i_file_acl_high osd2.masix2.m_i_file_acl_high
 798 #define i_reserved2     osd2.masix2.m_i_reserved2
 799
 800 #endif /* defined(__KERNEL__) || defined(__linux__) */
 801
 802 /*
 803  * storage for cached extent
 804  * If ec_len == 0, then the cache is invalid.
 805  * If ec_start == 0, then the cache represents a gap (null mapping)
 806  */
 807 struct ext4_ext_cache {
 808         ext4_fsblk_t    ec_start;
 809         ext4_lblk_t     ec_block;
 810         __u32           ec_len; /* must be 32bit to return holes */
 811 };
 812
 813 /*
 814  * fourth extended file system inode data in memory
 815  */
 816 struct ext4_inode_info {
 817         __le32  i_data[15];     /* unconverted */
 818         __u32   i_dtime;
 819         ext4_fsblk_t    i_file_acl;
 820
 821         /*
 822          * i_block_group is the number of the block group which contains
 823          * this file's inode.  Constant across the lifetime of the inode,
 824          * it is ued for making block allocation decisions - we try to
 825          * place a file's data blocks near its inode block, and new inodes
 826          * near to their parent directory's inode.
 827          */
 828         ext4_group_t    i_block_group;
 829         ext4_lblk_t     i_dir_start_lookup;
 830 #if (BITS_PER_LONG < 64)
 831         unsigned long   i_state_flags;          /* Dynamic state flags */
 832 #endif
 833         unsigned long   i_flags;
 834
 835 #ifdef CONFIG_EXT4_FS_XATTR
 836         /*
 837          * Extended attributes can be read independently of the main file
 838          * data. Taking i_mutex even when reading would cause contention
 839          * between readers of EAs and writers of regular file data, so
 840          * instead we synchronize on xattr_sem when reading or changing
 841          * EAs.
 842          */
 843         struct rw_semaphore xattr_sem;
 844 #endif
 845
 846         struct list_head i_orphan;      /* unlinked but open inodes */
 847
 848         /*
 849          * i_disksize keeps track of what the inode size is ON DISK, not
 850          * in memory.  During truncate, i_size is set to the new size by
 851          * the VFS prior to calling ext4_truncate(), but the filesystem won't
 852          * set i_disksize to 0 until the truncate is actually under way.
 853          *
 854          * The intent is that i_disksize always represents the blocks which
 855          * are used by this file.  This allows recovery to restart truncate
 856          * on orphans if we crash during truncate.  We actually write i_disksize
 857          * into the on-disk inode when writing inodes out, instead of i_size.
 858          *
 859          * The only time when i_disksize and i_size may be different is when
 860          * a truncate is in progress.  The only things which change i_disksize
 861          * are ext4_get_block (growth) and ext4_truncate (shrinkth).
 862          */
 863         loff_t  i_disksize;
 864
 865         /*
 866          * i_data_sem is for serialising ext4_truncate() against
 867          * ext4_getblock().  In the 2.4 ext2 design, great chunks of inode's
 868          * data tree are chopped off during truncate. We can't do that in
 869          * ext4 because whenever we perform intermediate commits during
 870          * truncate, the inode and all the metadata blocks *must* be in a
 871          * consistent state which allows truncation of the orphans to restart
 872          * during recovery.  Hence we must fix the get_block-vs-truncate race
 873          * by other means, so we have i_data_sem.
 874          */
 875         struct rw_semaphore i_data_sem;
 876         struct inode vfs_inode;
 877         struct jbd2_inode *jinode;
 878
 879         struct ext4_ext_cache i_cached_extent;
 880         /*
 881          * File creation time. Its function is same as that of
 882          * struct timespec i_{a,c,m}time in the generic inode.
 883          */
 884         struct timespec i_crtime;
 885
 886         /* mballoc */
 887         struct list_head i_prealloc_list;
 888         spinlock_t i_prealloc_lock;
 889
 890         /* ialloc */
 891         ext4_group_t    i_last_alloc_group;
 892
 893         /* allocation reservation info for delalloc */
 894         /* In case of bigalloc, these refer to clusters rather than blocks */
 895         unsigned int i_reserved_data_blocks;
 896         unsigned int i_reserved_meta_blocks;
 897         unsigned int i_allocated_meta_blocks;
 898         ext4_lblk_t i_da_metadata_calc_last_lblock;
 899         int i_da_metadata_calc_len;
 900
 901         /* on-disk additional length */
 902         __u16 i_extra_isize;
 903
 904 #ifdef CONFIG_QUOTA
 905         /* quota space reservation, managed internally by quota code */
 906         qsize_t i_reserved_quota;
 907 #endif
 908
 909         /* completed IOs that might need unwritten extents handling */
 910         struct list_head i_completed_io_list;
 911         spinlock_t i_completed_io_lock;
 912         atomic_t i_ioend_count; /* Number of outstanding io_end structs */
 913         /* current io_end structure for async DIO write*/
 914         ext4_io_end_t *cur_aio_dio;
 915         atomic_t i_aiodio_unwritten; /* Nr. of inflight conversions pending */
 916
 917         spinlock_t i_block_reservation_lock;
 918
 919         /*
 920          * Transactions that contain inode's metadata needed to complete
 921          * fsync and fdatasync, respectively.
 922          */
 923         tid_t i_sync_tid;
 924         tid_t i_datasync_tid;
 925
 926         /* Precomputed uuid+inum+igen checksum for seeding inode checksums */
 927         __u32 i_csum_seed;
 928 };
 929
 930 /*
 931  * File system states
 932  */
 933 #define EXT4_VALID_FS                   0x0001  /* Unmounted cleanly */
 934 #define EXT4_ERROR_FS                   0x0002  /* Errors detected */
 935 #define EXT4_ORPHAN_FS                  0x0004  /* Orphans being recovered */
 936
 937 /*
 938  * Misc. filesystem flags
 939  */
 940 #define EXT2_FLAGS_SIGNED_HASH          0x0001  /* Signed dirhash in use */
 941 #define EXT2_FLAGS_UNSIGNED_HASH        0x0002  /* Unsigned dirhash in use */
 942 #define EXT2_FLAGS_TEST_FILESYS         0x0004  /* to test development code */
 943
 944 /*
 945  * Mount flags
 946  */
 947 #define EXT4_MOUNT_GRPID                0x00004 /* Create files with directory's group */
 948 #define EXT4_MOUNT_DEBUG                0x00008 /* Some debugging messages */
 949 #define EXT4_MOUNT_ERRORS_CONT          0x00010 /* Continue on errors */
 950 #define EXT4_MOUNT_ERRORS_RO            0x00020 /* Remount fs ro on errors */
 951 #define EXT4_MOUNT_ERRORS_PANIC         0x00040 /* Panic on errors */
 952 #define EXT4_MOUNT_ERRORS_MASK          0x00070
 953 #define EXT4_MOUNT_MINIX_DF             0x00080 /* Mimics the Minix statfs */
 954 #define EXT4_MOUNT_NOLOAD               0x00100 /* Don't use existing journal*/
 955 #define EXT4_MOUNT_DATA_FLAGS           0x00C00 /* Mode for data writes: */
 956 #define EXT4_MOUNT_JOURNAL_DATA         0x00400 /* Write data to journal */
 957 #define EXT4_MOUNT_ORDERED_DATA         0x00800 /* Flush data before commit */
 958 #define EXT4_MOUNT_WRITEBACK_DATA       0x00C00 /* No data ordering */
 959 #define EXT4_MOUNT_UPDATE_JOURNAL       0x01000 /* Update the journal format */
 960 #define EXT4_MOUNT_NO_UID32             0x02000  /* Disable 32-bit UIDs */
 961 #define EXT4_MOUNT_XATTR_USER           0x04000 /* Extended user attributes */
 962 #define EXT4_MOUNT_POSIX_ACL            0x08000 /* POSIX Access Control Lists */
 963 #define EXT4_MOUNT_NO_AUTO_DA_ALLOC     0x10000 /* No auto delalloc mapping */
 964 #define EXT4_MOUNT_BARRIER              0x20000 /* Use block barriers */
 965 #define EXT4_MOUNT_QUOTA                0x80000 /* Some quota option set */
 966 #define EXT4_MOUNT_USRQUOTA             0x100000 /* "old" user quota */
 967 #define EXT4_MOUNT_GRPQUOTA             0x200000 /* "old" group quota */
 968 #define EXT4_MOUNT_DIOREAD_NOLOCK       0x400000 /* Enable support for dio read nolocking */
 969 #define EXT4_MOUNT_JOURNAL_CHECKSUM     0x800000 /* Journal checksums */
 970 #define EXT4_MOUNT_JOURNAL_ASYNC_COMMIT 0x1000000 /* Journal Async Commit */
 971 #define EXT4_MOUNT_MBLK_IO_SUBMIT       0x4000000 /* multi-block io submits */
 972 #define EXT4_MOUNT_DELALLOC             0x8000000 /* Delalloc support */
 973 #define EXT4_MOUNT_DATA_ERR_ABORT       0x10000000 /* Abort on file data write */
 974 #define EXT4_MOUNT_BLOCK_VALIDITY       0x20000000 /* Block validity checking */
 975 #define EXT4_MOUNT_DISCARD              0x40000000 /* Issue DISCARD requests */
 976 #define EXT4_MOUNT_INIT_INODE_TABLE     0x80000000 /* Initialize uninitialized itables */
 977
 978 #define EXT4_MOUNT2_EXPLICIT_DELALLOC   0x00000001 /* User explicitly
 979                                                       specified delalloc */
 980
 981 #define clear_opt(sb, opt)              EXT4_SB(sb)->s_mount_opt &= \
 982                                                 ~EXT4_MOUNT_##opt
 983 #define set_opt(sb, opt)                EXT4_SB(sb)->s_mount_opt |= \
 984                                                 EXT4_MOUNT_##opt
 985 #define test_opt(sb, opt)               (EXT4_SB(sb)->s_mount_opt & \
 986                                          EXT4_MOUNT_##opt)
 987
 988 #define clear_opt2(sb, opt)             EXT4_SB(sb)->s_mount_opt2 &= \
 989                                                 ~EXT4_MOUNT2_##opt
 990 #define set_opt2(sb, opt)               EXT4_SB(sb)->s_mount_opt2 |= \
 991                                                 EXT4_MOUNT2_##opt
 992 #define test_opt2(sb, opt)              (EXT4_SB(sb)->s_mount_opt2 & \
 993                                          EXT4_MOUNT2_##opt)
 994
 995 #define ext4_test_and_set_bit           __test_and_set_bit_le
 996 #define ext4_set_bit                    __set_bit_le
 997 #define ext4_set_bit_atomic             ext2_set_bit_atomic
 998 #define ext4_test_and_clear_bit         __test_and_clear_bit_le
 999 #define ext4_clear_bit                  __clear_bit_le
1000 #define ext4_clear_bit_atomic           ext2_clear_bit_atomic
1001 #define ext4_test_bit                   test_bit_le
1002 #define ext4_find_next_zero_bit         find_next_zero_bit_le
1003 #define ext4_find_next_bit              find_next_bit_le
1004
1005 extern void ext4_set_bits(void *bm, int cur, int len);
1006
1007 /*
1008  * Maximal mount counts between two filesystem checks
1009  */
1010 #define EXT4_DFL_MAX_MNT_COUNT          20      /* Allow 20 mounts */
1011 #define EXT4_DFL_CHECKINTERVAL          0       /* Don't use interval check */
1012
1013 /*
1014  * Behaviour when detecting errors
1015  */
1016 #define EXT4_ERRORS_CONTINUE            1       /* Continue execution */
1017 #define EXT4_ERRORS_RO                  2       /* Remount fs read-only */
1018 #define EXT4_ERRORS_PANIC               3       /* Panic */
1019 #define EXT4_ERRORS_DEFAULT             EXT4_ERRORS_CONTINUE
1020
1021 /* Metadata checksum algorithm codes */
1022 #define EXT4_CRC32C_CHKSUM              1
1023
1024 /*
1025  * Structure of the super block
1026  */
1027 struct ext4_super_block {
1028 /*00*/  __le32  s_inodes_count;         /* Inodes count */
1029         __le32  s_blocks_count_lo;      /* Blocks count */
1030         __le32  s_r_blocks_count_lo;    /* Reserved blocks count */
1031         __le32  s_free_blocks_count_lo; /* Free blocks count */
1032 /*10*/  __le32  s_free_inodes_count;    /* Free inodes count */
1033         __le32  s_first_data_block;     /* First Data Block */
1034         __le32  s_log_block_size;       /* Block size */
1035         __le32  s_log_cluster_size;     /* Allocation cluster size */
1036 /*20*/  __le32  s_blocks_per_group;     /* # Blocks per group */
1037         __le32  s_clusters_per_group;   /* # Clusters per group */
1038         __le32  s_inodes_per_group;     /* # Inodes per group */
1039         __le32  s_mtime;                /* Mount time */
1040 /*30*/  __le32  s_wtime;                /* Write time */
1041         __le16  s_mnt_count;            /* Mount count */
1042         __le16  s_max_mnt_count;        /* Maximal mount count */
1043         __le16  s_magic;                /* Magic signature */
1044         __le16  s_state;                /* File system state */
1045         __le16  s_errors;               /* Behaviour when detecting errors */
1046         __le16  s_minor_rev_level;      /* minor revision level */
1047 /*40*/  __le32  s_lastcheck;            /* time of last check */
1048         __le32  s_checkinterval;        /* max. time between checks */
1049         __le32  s_creator_os;           /* OS */
1050         __le32  s_rev_level;            /* Revision level */
1051 /*50*/  __le16  s_def_resuid;           /* Default uid for reserved blocks */
1052         __le16  s_def_resgid;           /* Default gid for reserved blocks */
1053         /*
1054          * These fields are for EXT4_DYNAMIC_REV superblocks only.
1055          *
1056          * Note: the difference between the compatible feature set and
1057          * the incompatible feature set is that if there is a bit set
1058          * in the incompatible feature set that the kernel doesn't
1059          * know about, it should refuse to mount the filesystem.
1060          *
1061          * e2fsck's requirements are more strict; if it doesn't know
1062          * about a feature in either the compatible or incompatible
1063          * feature set, it must abort and not try to meddle with
1064          * things it doesn't understand...
1065          */
1066         __le32  s_first_ino;            /* First non-reserved inode */
1067         __le16  s_inode_size;           /* size of inode structure */
1068         __le16  s_block_group_nr;       /* block group # of this superblock */
1069         __le32  s_feature_compat;       /* compatible feature set */
1070 /*60*/  __le32  s_feature_incompat;     /* incompatible feature set */
1071         __le32  s_feature_ro_compat;    /* readonly-compatible feature set */
1072 /*68*/  __u8    s_uuid[16];             /* 128-bit uuid for volume */
1073 /*78*/  char    s_volume_name[16];      /* volume name */
1074 /*88*/  char    s_last_mounted[64];     /* directory where last mounted */
1075 /*C8*/  __le32  s_algorithm_usage_bitmap; /* For compression */
1076         /*
1077          * Performance hints.  Directory preallocation should only
1078          * happen if the EXT4_FEATURE_COMPAT_DIR_PREALLOC flag is on.
1079          */
1080         __u8    s_prealloc_blocks;      /* Nr of blocks to try to preallocate*/
1081         __u8    s_prealloc_dir_blocks;  /* Nr to preallocate for dirs */
1082         __le16  s_reserved_gdt_blocks;  /* Per group desc for online growth */
1083         /*
1084          * Journaling support valid if EXT4_FEATURE_COMPAT_HAS_JOURNAL set.
1085          */
1086 /*D0*/  __u8    s_journal_uuid[16];     /* uuid of journal superblock */
1087 /*E0*/  __le32  s_journal_inum;         /* inode number of journal file */
1088         __le32  s_journal_dev;          /* device number of journal file */
1089         __le32  s_last_orphan;          /* start of list of inodes to delete */
1090         __le32  s_hash_seed[4];         /* HTREE hash seed */
1091         __u8    s_def_hash_version;     /* Default hash version to use */
1092         __u8    s_jnl_backup_type;
1093         __le16  s_desc_size;            /* size of group descriptor */
1094 /*100*/ __le32  s_default_mount_opts;
1095         __le32  s_first_meta_bg;        /* First metablock block group */
1096         __le32  s_mkfs_time;            /* When the filesystem was created */
1097         __le32  s_jnl_blocks[17];       /* Backup of the journal inode */
1098         /* 64bit support valid if EXT4_FEATURE_COMPAT_64BIT */
1099 /*150*/ __le32  s_blocks_count_hi;      /* Blocks count */
1100         __le32  s_r_blocks_count_hi;    /* Reserved blocks count */
1101         __le32  s_free_blocks_count_hi; /* Free blocks count */
1102         __le16  s_min_extra_isize;      /* All inodes have at least # bytes */
1103         __le16  s_want_extra_isize;     /* New inodes should reserve # bytes */
1104         __le32  s_flags;                /* Miscellaneous flags */
1105         __le16  s_raid_stride;          /* RAID stride */
1106         __le16  s_mmp_update_interval;  /* # seconds to wait in MMP checking */
1107         __le64  s_mmp_block;            /* Block for multi-mount protection */
1108         __le32  s_raid_stripe_width;    /* blocks on all data disks (N*stride)*/
1109         __u8    s_log_groups_per_flex;  /* FLEX_BG group size */
1110         __u8    s_checksum_type;        /* metadata checksum algorithm used */
1111         __le16  s_reserved_pad;
1112         __le64  s_kbytes_written;       /* nr of lifetime kilobytes written */
1113         __le32  s_snapshot_inum;        /* Inode number of active snapshot */
1114         __le32  s_snapshot_id;          /* sequential ID of active snapshot */
1115         __le64  s_snapshot_r_blocks_count; /* reserved blocks for active
1116                                               snapshot's future use */
1117         __le32  s_snapshot_list;        /* inode number of the head of the
1118                                            on-disk snapshot list */
1119 #define EXT4_S_ERR_START offsetof(struct ext4_super_block, s_error_count)
1120         __le32  s_error_count;          /* number of fs errors */
1121         __le32  s_first_error_time;     /* first time an error happened */
1122         __le32  s_first_error_ino;      /* inode involved in first error */
1123         __le64  s_first_error_block;    /* block involved of first error */
1124         __u8    s_first_error_func[32]; /* function where the error happened */
1125         __le32  s_first_error_line;     /* line number where error happened */
1126         __le32  s_last_error_time;      /* most recent time of an error */
1127         __le32  s_last_error_ino;       /* inode involved in last error */
1128         __le32  s_last_error_line;      /* line number where error happened */
1129         __le64  s_last_error_block;     /* block involved of last error */
1130         __u8    s_last_error_func[32];  /* function where the error happened */
1131 #define EXT4_S_ERR_END offsetof(struct ext4_super_block, s_mount_opts)
1132         __u8    s_mount_opts[64];
1133         __le32  s_usr_quota_inum;       /* inode for tracking user quota */
1134         __le32  s_grp_quota_inum;       /* inode for tracking group quota */
1135         __le32  s_overhead_clusters;    /* overhead blocks/clusters in fs */
1136         __le32  s_reserved[108];        /* Padding to the end of the block */
1137         __le32  s_checksum;             /* crc32c(superblock) */
1138 };
1139
1140 #define EXT4_S_ERR_LEN (EXT4_S_ERR_END - EXT4_S_ERR_START)
1141
1142 #ifdef __KERNEL__
1143
1144 /*
1145  * run-time mount flags
1146  */
1147 #define EXT4_MF_MNTDIR_SAMPLED  0x0001
1148 #define EXT4_MF_FS_ABORTED      0x0002  /* Fatal error detected */
1149
1150 /*
1151  * fourth extended-fs super-block data in memory
1152  */
1153 struct ext4_sb_info {
1154         unsigned long s_desc_size;      /* Size of a group descriptor in bytes */
1155         unsigned long s_inodes_per_block;/* Number of inodes per block */
1156         unsigned long s_blocks_per_group;/* Number of blocks in a group */
1157         unsigned long s_clusters_per_group; /* Number of clusters in a group */
1158         unsigned long s_inodes_per_group;/* Number of inodes in a group */
1159         unsigned long s_itb_per_group;  /* Number of inode table blocks per group */
1160         unsigned long s_gdb_count;      /* Number of group descriptor blocks */
1161         unsigned long s_desc_per_block; /* Number of group descriptors per block */
1162         ext4_group_t s_groups_count;    /* Number of groups in the fs */
1163         ext4_group_t s_blockfile_groups;/* Groups acceptable for non-extent files */
1164         unsigned long s_overhead_last;  /* Last calculated overhead */
1165         unsigned long s_blocks_last;    /* Last seen block count */
1166         unsigned int s_cluster_ratio;   /* Number of blocks per cluster */
1167         unsigned int s_cluster_bits;    /* log2 of s_cluster_ratio */
1168         loff_t s_bitmap_maxbytes;       /* max bytes for bitmap files */
1169         struct buffer_head * s_sbh;     /* Buffer containing the super block */
1170         struct ext4_super_block *s_es;  /* Pointer to the super block in the buffer */
1171         struct buffer_head **s_group_desc;
1172         unsigned int s_mount_opt;
1173         unsigned int s_mount_opt2;
1174         unsigned int s_mount_flags;
1175         unsigned int s_def_mount_opt;
1176         ext4_fsblk_t s_sb_block;
1177         kuid_t s_resuid;
1178         kgid_t s_resgid;
1179         unsigned short s_mount_state;
1180         unsigned short s_pad;
1181         int s_addr_per_block_bits;
1182         int s_desc_per_block_bits;
1183         int s_inode_size;
1184         int s_first_ino;
1185         unsigned int s_inode_readahead_blks;
1186         unsigned int s_inode_goal;
1187         spinlock_t s_next_gen_lock;
1188         u32 s_next_generation;
1189         u32 s_hash_seed[4];
1190         int s_def_hash_version;
1191         int s_hash_unsigned;    /* 3 if hash should be signed, 0 if not */
1192         struct percpu_counter s_freeclusters_counter;
1193         struct percpu_counter s_freeinodes_counter;
1194         struct percpu_counter s_dirs_counter;
1195         struct percpu_counter s_dirtyclusters_counter;
1196         struct blockgroup_lock *s_blockgroup_lock;
1197         struct proc_dir_entry *s_proc;
1198         struct kobject s_kobj;
1199         struct completion s_kobj_unregister;
1200         struct super_block *s_sb;
1201
1202         /* Journaling */
1203         struct journal_s *s_journal;
1204         struct list_head s_orphan;
1205         struct mutex s_orphan_lock;
1206         unsigned long s_resize_flags;           /* Flags indicating if there
1207                                                    is a resizer */
1208         unsigned long s_commit_interval;
1209         u32 s_max_batch_time;
1210         u32 s_min_batch_time;
1211         struct block_device *journal_bdev;
1212 #ifdef CONFIG_QUOTA
1213         char *s_qf_names[MAXQUOTAS];            /* Names of quota files with journalled quota */
1214         int s_jquota_fmt;                       /* Format of quota to use */
1215 #endif
1216         unsigned int s_want_extra_isize; /* New inodes should reserve # bytes */
1217         struct rb_root system_blks;
1218
1219 #ifdef EXTENTS_STATS
1220         /* ext4 extents stats */
1221         unsigned long s_ext_min;
1222         unsigned long s_ext_max;
1223         unsigned long s_depth_max;
1224         spinlock_t s_ext_stats_lock;
1225         unsigned long s_ext_blocks;
1226         unsigned long s_ext_extents;
1227 #endif
1228
1229         /* for buddy allocator */
1230         struct ext4_group_info ***s_group_info;
1231         struct inode *s_buddy_cache;
1232         spinlock_t s_md_lock;
1233         unsigned short *s_mb_offsets;
1234         unsigned int *s_mb_maxs;
1235
1236         /* tunables */
1237         unsigned long s_stripe;
1238         unsigned int s_mb_stream_request;
1239         unsigned int s_mb_max_to_scan;
1240         unsigned int s_mb_min_to_scan;
1241         unsigned int s_mb_stats;
1242         unsigned int s_mb_order2_reqs;
1243         unsigned int s_mb_group_prealloc;
1244         unsigned int s_max_writeback_mb_bump;
1245         /* where last allocation was done - for stream allocation */
1246         unsigned long s_mb_last_group;
1247         unsigned long s_mb_last_start;
1248
1249         /* stats for buddy allocator */
1250         atomic_t s_bal_reqs;    /* number of reqs with len > 1 */
1251         atomic_t s_bal_success; /* we found long enough chunks */
1252         atomic_t s_bal_allocated;       /* in blocks */
1253         atomic_t s_bal_ex_scanned;      /* total extents scanned */
1254         atomic_t s_bal_goals;   /* goal hits */
1255         atomic_t s_bal_breaks;  /* too long searches */
1256         atomic_t s_bal_2orders; /* 2^order hits */
1257         spinlock_t s_bal_lock;
1258         unsigned long s_mb_buddies_generated;
1259         unsigned long long s_mb_generation_time;
1260         atomic_t s_mb_lost_chunks;
1261         atomic_t s_mb_preallocated;
1262         atomic_t s_mb_discarded;
1263         atomic_t s_lock_busy;
1264
1265         /* locality groups */
1266         struct ext4_locality_group __percpu *s_locality_groups;
1267
1268         /* for write statistics */
1269         unsigned long s_sectors_written_start;
1270         u64 s_kbytes_written;
1271
1272         unsigned int s_log_groups_per_flex;
1273         struct flex_groups *s_flex_groups;
1274
1275         /* workqueue for dio unwritten */
1276         struct workqueue_struct *dio_unwritten_wq;
1277
1278         /* timer for periodic error stats printing */
1279         struct timer_list s_err_report;
1280
1281         /* Lazy inode table initialization info */
1282         struct ext4_li_request *s_li_request;
1283         /* Wait multiplier for lazy initialization thread */
1284         unsigned int s_li_wait_mult;
1285
1286         /* Kernel thread for multiple mount protection */
1287         struct task_struct *s_mmp_tsk;
1288
1289         /* record the last minlen when FITRIM is called. */
1290         atomic_t s_last_trim_minblks;
1291
1292         /* Reference to checksum algorithm driver via cryptoapi */
1293         struct crypto_shash *s_chksum_driver;
1294
1295         /* Precomputed FS UUID checksum for seeding other checksums */
1296         __u32 s_csum_seed;
1297 };
1298
1299 static inline struct ext4_sb_info *EXT4_SB(struct super_block *sb)
1300 {
1301         return sb->s_fs_info;
1302 }
1303 static inline struct ext4_inode_info *EXT4_I(struct inode *inode)
1304 {
1305         return container_of(inode, struct ext4_inode_info, vfs_inode);
1306 }
1307
1308 static inline struct timespec ext4_current_time(struct inode *inode)
1309 {
1310         return (inode->i_sb->s_time_gran < NSEC_PER_SEC) ?
1311                 current_fs_time(inode->i_sb) : CURRENT_TIME_SEC;
1312 }
1313
1314 static inline int ext4_valid_inum(struct super_block *sb, unsigned long ino)
1315 {
1316         return ino == EXT4_ROOT_INO ||
1317                 ino == EXT4_JOURNAL_INO ||
1318                 ino == EXT4_RESIZE_INO ||
1319                 (ino >= EXT4_FIRST_INO(sb) &&
1320                  ino <= le32_to_cpu(EXT4_SB(sb)->s_es->s_inodes_count));
1321 }
1322
1323 static inline void ext4_set_io_unwritten_flag(struct inode *inode,
1324                                               struct ext4_io_end *io_end)
1325 {
1326         if (!(io_end->flag & EXT4_IO_END_UNWRITTEN)) {
1327                 io_end->flag |= EXT4_IO_END_UNWRITTEN;
1328                 atomic_inc(&EXT4_I(inode)->i_aiodio_unwritten);
1329         }
1330 }
1331
1332 /*
1333  * Inode dynamic state flags
1334  */
1335 enum {
1336         EXT4_STATE_JDATA,               /* journaled data exists */
1337         EXT4_STATE_NEW,                 /* inode is newly created */
1338         EXT4_STATE_XATTR,               /* has in-inode xattrs */
1339         EXT4_STATE_NO_EXPAND,           /* No space for expansion */
1340         EXT4_STATE_DA_ALLOC_CLOSE,      /* Alloc DA blks on close */
1341         EXT4_STATE_EXT_MIGRATE,         /* Inode is migrating */
1342         EXT4_STATE_DIO_UNWRITTEN,       /* need convert on dio done*/
1343         EXT4_STATE_NEWENTRY,            /* File just added to dir */
1344         EXT4_STATE_DELALLOC_RESERVED,   /* blks already reserved for delalloc */
1345 };
1346
1347 #define EXT4_INODE_BIT_FNS(name, field, offset)                         \
1348 static inline int ext4_test_inode_##name(struct inode *inode, int bit)  \
1349 {                                                                       \
1350         return test_bit(bit + (offset), &EXT4_I(inode)->i_##field);     \
1351 }                                                                       \
1352 static inline void ext4_set_inode_##name(struct inode *inode, int bit)  \
1353 {                                                                       \
1354         set_bit(bit + (offset), &EXT4_I(inode)->i_##field);             \
1355 }                                                                       \
1356 static inline void ext4_clear_inode_##name(struct inode *inode, int bit) \
1357 {                                                                       \
1358         clear_bit(bit + (offset), &EXT4_I(inode)->i_##field);           \
1359 }
1360
1361 EXT4_INODE_BIT_FNS(flag, flags, 0)
1362 #if (BITS_PER_LONG < 64)
1363 EXT4_INODE_BIT_FNS(state, state_flags, 0)
1364
1365 static inline void ext4_clear_state_flags(struct ext4_inode_info *ei)
1366 {
1367         (ei)->i_state_flags = 0;
1368 }
1369 #else
1370 EXT4_INODE_BIT_FNS(state, flags, 32)
1371
1372 static inline void ext4_clear_state_flags(struct ext4_inode_info *ei)
1373 {
1374         /* We depend on the fact that callers will set i_flags */
1375 }
1376 #endif
1377 #else
1378 /* Assume that user mode programs are passing in an ext4fs superblock, not
1379  * a kernel struct super_block.  This will allow us to call the feature-test
1380  * macros from user land. */
1381 #define EXT4_SB(sb)     (sb)
1382 #endif
1383
1384 #define NEXT_ORPHAN(inode) EXT4_I(inode)->i_dtime
1385
1386 /*
1387  * Codes for operating systems
1388  */
1389 #define EXT4_OS_LINUX           0
1390 #define EXT4_OS_HURD            1
1391 #define EXT4_OS_MASIX           2
1392 #define EXT4_OS_FREEBSD         3
1393 #define EXT4_OS_LITES           4
1394
1395 /*
1396  * Revision levels
1397  */
1398 #define EXT4_GOOD_OLD_REV       0       /* The good old (original) format */
1399 #define EXT4_DYNAMIC_REV        1       /* V2 format w/ dynamic inode sizes */
1400
1401 #define EXT4_CURRENT_REV        EXT4_GOOD_OLD_REV
1402 #define EXT4_MAX_SUPP_REV       EXT4_DYNAMIC_REV
1403
1404 #define EXT4_GOOD_OLD_INODE_SIZE 128
1405
1406 /*
1407  * Feature set definitions
1408  */
1409
1410 #define EXT4_HAS_COMPAT_FEATURE(sb,mask)                        \
1411         ((EXT4_SB(sb)->s_es->s_feature_compat & cpu_to_le32(mask)) != 0)
1412 #define EXT4_HAS_RO_COMPAT_FEATURE(sb,mask)                     \
1413         ((EXT4_SB(sb)->s_es->s_feature_ro_compat & cpu_to_le32(mask)) != 0)
1414 #define EXT4_HAS_INCOMPAT_FEATURE(sb,mask)                      \
1415         ((EXT4_SB(sb)->s_es->s_feature_incompat & cpu_to_le32(mask)) != 0)
1416 #define EXT4_SET_COMPAT_FEATURE(sb,mask)                        \
1417         EXT4_SB(sb)->s_es->s_feature_compat |= cpu_to_le32(mask)
1418 #define EXT4_SET_RO_COMPAT_FEATURE(sb,mask)                     \
1419         EXT4_SB(sb)->s_es->s_feature_ro_compat |= cpu_to_le32(mask)
1420 #define EXT4_SET_INCOMPAT_FEATURE(sb,mask)                      \
1421         EXT4_SB(sb)->s_es->s_feature_incompat |= cpu_to_le32(mask)
1422 #define EXT4_CLEAR_COMPAT_FEATURE(sb,mask)                      \
1423         EXT4_SB(sb)->s_es->s_feature_compat &= ~cpu_to_le32(mask)
1424 #define EXT4_CLEAR_RO_COMPAT_FEATURE(sb,mask)                   \
1425         EXT4_SB(sb)->s_es->s_feature_ro_compat &= ~cpu_to_le32(mask)
1426 #define EXT4_CLEAR_INCOMPAT_FEATURE(sb,mask)                    \
1427         EXT4_SB(sb)->s_es->s_feature_incompat &= ~cpu_to_le32(mask)
1428
1429 #define EXT4_FEATURE_COMPAT_DIR_PREALLOC        0x0001
1430 #define EXT4_FEATURE_COMPAT_IMAGIC_INODES       0x0002
1431 #define EXT4_FEATURE_COMPAT_HAS_JOURNAL         0x0004
1432 #define EXT4_FEATURE_COMPAT_EXT_ATTR            0x0008
1433 #define EXT4_FEATURE_COMPAT_RESIZE_INODE        0x0010
1434 #define EXT4_FEATURE_COMPAT_DIR_INDEX           0x0020
1435
1436 #define EXT4_FEATURE_RO_COMPAT_SPARSE_SUPER     0x0001
1437 #define EXT4_FEATURE_RO_COMPAT_LARGE_FILE       0x0002
1438 #define EXT4_FEATURE_RO_COMPAT_BTREE_DIR        0x0004
1439 #define EXT4_FEATURE_RO_COMPAT_HUGE_FILE        0x0008
1440 #define EXT4_FEATURE_RO_COMPAT_GDT_CSUM         0x0010
1441 #define EXT4_FEATURE_RO_COMPAT_DIR_NLINK        0x0020
1442 #define EXT4_FEATURE_RO_COMPAT_EXTRA_ISIZE      0x0040
1443 #define EXT4_FEATURE_RO_COMPAT_QUOTA            0x0100
1444 #define EXT4_FEATURE_RO_COMPAT_BIGALLOC         0x0200
1445 /*
1446  * METADATA_CSUM also enables group descriptor checksums (GDT_CSUM).  When
1447  * METADATA_CSUM is set, group descriptor checksums use the same algorithm as
1448  * all other data structures' checksums.  However, the METADATA_CSUM and
1449  * GDT_CSUM bits are mutually exclusive.
1450  */
1451 #define EXT4_FEATURE_RO_COMPAT_METADATA_CSUM    0x0400
1452
1453 #define EXT4_FEATURE_INCOMPAT_COMPRESSION       0x0001
1454 #define EXT4_FEATURE_INCOMPAT_FILETYPE          0x0002
1455 #define EXT4_FEATURE_INCOMPAT_RECOVER           0x0004 /* Needs recovery */
1456 #define EXT4_FEATURE_INCOMPAT_JOURNAL_DEV       0x0008 /* Journal device */
1457 #define EXT4_FEATURE_INCOMPAT_META_BG           0x0010
1458 #define EXT4_FEATURE_INCOMPAT_EXTENTS           0x0040 /* extents support */
1459 #define EXT4_FEATURE_INCOMPAT_64BIT             0x0080
1460 #define EXT4_FEATURE_INCOMPAT_MMP               0x0100
1461 #define EXT4_FEATURE_INCOMPAT_FLEX_BG           0x0200
1462 #define EXT4_FEATURE_INCOMPAT_EA_INODE          0x0400 /* EA in inode */
1463 #define EXT4_FEATURE_INCOMPAT_DIRDATA           0x1000 /* data in dirent */
1464 #define EXT4_FEATURE_INCOMPAT_BG_USE_META_CSUM  0x2000 /* use crc32c for bg */
1465 #define EXT4_FEATURE_INCOMPAT_LARGEDIR          0x4000 /* >2GB or 3-lvl htree */
1466 #define EXT4_FEATURE_INCOMPAT_INLINEDATA        0x8000 /* data in inode */
1467
1468 #define EXT2_FEATURE_COMPAT_SUPP        EXT4_FEATURE_COMPAT_EXT_ATTR
1469 #define EXT2_FEATURE_INCOMPAT_SUPP      (EXT4_FEATURE_INCOMPAT_FILETYPE| \
1470                                          EXT4_FEATURE_INCOMPAT_META_BG)
1471 #define EXT2_FEATURE_RO_COMPAT_SUPP     (EXT4_FEATURE_RO_COMPAT_SPARSE_SUPER| \
1472                                          EXT4_FEATURE_RO_COMPAT_LARGE_FILE| \
1473                                          EXT4_FEATURE_RO_COMPAT_BTREE_DIR)
1474
1475 #define EXT3_FEATURE_COMPAT_SUPP        EXT4_FEATURE_COMPAT_EXT_ATTR
1476 #define EXT3_FEATURE_INCOMPAT_SUPP      (EXT4_FEATURE_INCOMPAT_FILETYPE| \
1477                                          EXT4_FEATURE_INCOMPAT_RECOVER| \
1478                                          EXT4_FEATURE_INCOMPAT_META_BG)
1479 #define EXT3_FEATURE_RO_COMPAT_SUPP     (EXT4_FEATURE_RO_COMPAT_SPARSE_SUPER| \
1480                                          EXT4_FEATURE_RO_COMPAT_LARGE_FILE| \
1481                                          EXT4_FEATURE_RO_COMPAT_BTREE_DIR)
1482
1483 #define EXT4_FEATURE_COMPAT_SUPP        EXT2_FEATURE_COMPAT_EXT_ATTR
1484 #define EXT4_FEATURE_INCOMPAT_SUPP      (EXT4_FEATURE_INCOMPAT_FILETYPE| \
1485                                          EXT4_FEATURE_INCOMPAT_RECOVER| \
1486                                          EXT4_FEATURE_INCOMPAT_META_BG| \
1487                                          EXT4_FEATURE_INCOMPAT_EXTENTS| \
1488                                          EXT4_FEATURE_INCOMPAT_64BIT| \
1489                                          EXT4_FEATURE_INCOMPAT_FLEX_BG| \
1490                                          EXT4_FEATURE_INCOMPAT_MMP)
1491 #define EXT4_FEATURE_RO_COMPAT_SUPP     (EXT4_FEATURE_RO_COMPAT_SPARSE_SUPER| \
1492                                          EXT4_FEATURE_RO_COMPAT_LARGE_FILE| \
1493                                          EXT4_FEATURE_RO_COMPAT_GDT_CSUM| \
1494                                          EXT4_FEATURE_RO_COMPAT_DIR_NLINK | \
1495                                          EXT4_FEATURE_RO_COMPAT_EXTRA_ISIZE | \
1496                                          EXT4_FEATURE_RO_COMPAT_BTREE_DIR |\
1497                                          EXT4_FEATURE_RO_COMPAT_HUGE_FILE |\
1498                                          EXT4_FEATURE_RO_COMPAT_BIGALLOC |\
1499                                          EXT4_FEATURE_RO_COMPAT_METADATA_CSUM)
1500
1501 /*
1502  * Default values for user and/or group using reserved blocks
1503  */
1504 #define EXT4_DEF_RESUID         0
1505 #define EXT4_DEF_RESGID         0
1506
1507 #define EXT4_DEF_INODE_READAHEAD_BLKS   32
1508
1509 /*
1510  * Default mount options
1511  */
1512 #define EXT4_DEFM_DEBUG         0x0001
1513 #define EXT4_DEFM_BSDGROUPS     0x0002
1514 #define EXT4_DEFM_XATTR_USER    0x0004
1515 #define EXT4_DEFM_ACL           0x0008
1516 #define EXT4_DEFM_UID16         0x0010
1517 #define EXT4_DEFM_JMODE         0x0060
1518 #define EXT4_DEFM_JMODE_DATA    0x0020
1519 #define EXT4_DEFM_JMODE_ORDERED 0x0040
1520 #define EXT4_DEFM_JMODE_WBACK   0x0060
1521 #define EXT4_DEFM_NOBARRIER     0x0100
1522 #define EXT4_DEFM_BLOCK_VALIDITY 0x0200
1523 #define EXT4_DEFM_DISCARD       0x0400
1524 #define EXT4_DEFM_NODELALLOC    0x0800
1525
1526 /*
1527  * Default journal batch times
1528  */
1529 #define EXT4_DEF_MIN_BATCH_TIME 0
1530 #define EXT4_DEF_MAX_BATCH_TIME 15000 /* 15ms */
1531
1532 /*
1533  * Minimum number of groups in a flexgroup before we separate out
1534  * directories into the first block group of a flexgroup
1535  */
1536 #define EXT4_FLEX_SIZE_DIR_ALLOC_SCHEME 4
1537
1538 /*
1539  * Structure of a directory entry
1540  */
1541 #define EXT4_NAME_LEN 255
1542
1543 struct ext4_dir_entry {
1544         __le32  inode;                  /* Inode number */
1545         __le16  rec_len;                /* Directory entry length */
1546         __le16  name_len;               /* Name length */
1547         char    name[EXT4_NAME_LEN];    /* File name */
1548 };
1549
1550 /*
1551  * The new version of the directory entry.  Since EXT4 structures are
1552  * stored in intel byte order, and the name_len field could never be
1553  * bigger than 255 chars, it's safe to reclaim the extra byte for the
1554  * file_type field.
1555  */
1556 struct ext4_dir_entry_2 {
1557         __le32  inode;                  /* Inode number */
1558         __le16  rec_len;                /* Directory entry length */
1559         __u8    name_len;               /* Name length */
1560         __u8    file_type;
1561         char    name[EXT4_NAME_LEN];    /* File name */
1562 };
1563
1564 /*
1565  * This is a bogus directory entry at the end of each leaf block that
1566  * records checksums.
1567  */
1568 struct ext4_dir_entry_tail {
1569         __le32  det_reserved_zero1;     /* Pretend to be unused */
1570         __le16  det_rec_len;            /* 12 */
1571         __u8    det_reserved_zero2;     /* Zero name length */
1572         __u8    det_reserved_ft;        /* 0xDE, fake file type */
1573         __le32  det_checksum;           /* crc32c(uuid+inum+dirblock) */
1574 };
1575
1576 /*
1577  * Ext4 directory file types.  Only the low 3 bits are used.  The
1578  * other bits are reserved for now.
1579  */
1580 #define EXT4_FT_UNKNOWN         0
1581 #define EXT4_FT_REG_FILE        1
1582 #define EXT4_FT_DIR             2
1583 #define EXT4_FT_CHRDEV          3
1584 #define EXT4_FT_BLKDEV          4
1585 #define EXT4_FT_FIFO            5
1586 #define EXT4_FT_SOCK            6
1587 #define EXT4_FT_SYMLINK         7
1588
1589 #define EXT4_FT_MAX             8
1590
1591 #define EXT4_FT_DIR_CSUM        0xDE
1592
1593 /*
1594  * EXT4_DIR_PAD defines the directory entries boundaries
1595  *
1596  * NOTE: It must be a multiple of 4
1597  */
1598 #define EXT4_DIR_PAD                    4
1599 #define EXT4_DIR_ROUND                  (EXT4_DIR_PAD - 1)
1600 #define EXT4_DIR_REC_LEN(name_len)      (((name_len) + 8 + EXT4_DIR_ROUND) & \
1601                                          ~EXT4_DIR_ROUND)
1602 #define EXT4_MAX_REC_LEN                ((1<<16)-1)
1603
1604 /*
1605  * If we ever get support for fs block sizes > page_size, we'll need
1606  * to remove the #if statements in the next two functions...
1607  */
1608 static inline unsigned int
1609 ext4_rec_len_from_disk(__le16 dlen, unsigned blocksize)
1610 {
1611         unsigned len = le16_to_cpu(dlen);
1612
1613 #if (PAGE_CACHE_SIZE >= 65536)
1614         if (len == EXT4_MAX_REC_LEN || len == 0)
1615                 return blocksize;
1616         return (len & 65532) | ((len & 3) << 16);
1617 #else
1618         return len;
1619 #endif
1620 }
1621
1622 static inline __le16 ext4_rec_len_to_disk(unsigned len, unsigned blocksize)
1623 {
1624         if ((len > blocksize) || (blocksize > (1 << 18)) || (len & 3))
1625                 BUG();
1626 #if (PAGE_CACHE_SIZE >= 65536)
1627         if (len < 65536)
1628                 return cpu_to_le16(len);
1629         if (len == blocksize) {
1630                 if (blocksize == 65536)
1631                         return cpu_to_le16(EXT4_MAX_REC_LEN);
1632                 else
1633                         return cpu_to_le16(0);
1634         }
1635         return cpu_to_le16((len & 65532) | ((len >> 16) & 3));
1636 #else
1637         return cpu_to_le16(len);
1638 #endif
1639 }
1640
1641 /*
1642  * Hash Tree Directory indexing
1643  * (c) Daniel Phillips, 2001
1644  */
1645
1646 #define is_dx(dir) (EXT4_HAS_COMPAT_FEATURE(dir->i_sb, \
1647                                       EXT4_FEATURE_COMPAT_DIR_INDEX) && \
1648                     ext4_test_inode_flag((dir), EXT4_INODE_INDEX))
1649 #define EXT4_DIR_LINK_MAX(dir) (!is_dx(dir) && (dir)->i_nlink >= EXT4_LINK_MAX)
1650 #define EXT4_DIR_LINK_EMPTY(dir) ((dir)->i_nlink == 2 || (dir)->i_nlink == 1)
1651
1652 /* Legal values for the dx_root hash_version field: */
1653
1654 #define DX_HASH_LEGACY          0
1655 #define DX_HASH_HALF_MD4        1
1656 #define DX_HASH_TEA             2
1657 #define DX_HASH_LEGACY_UNSIGNED 3
1658 #define DX_HASH_HALF_MD4_UNSIGNED       4
1659 #define DX_HASH_TEA_UNSIGNED            5
1660
1661 static inline u32 ext4_chksum(struct ext4_sb_info *sbi, u32 crc,
1662                               const void *address, unsigned int length)
1663 {
1664         struct {
1665                 struct shash_desc shash;
1666                 char ctx[crypto_shash_descsize(sbi->s_chksum_driver)];
1667         } desc;
1668         int err;
1669
1670         desc.shash.tfm = sbi->s_chksum_driver;
1671         desc.shash.flags = 0;
1672         *(u32 *)desc.ctx = crc;
1673
1674         err = crypto_shash_update(&desc.shash, address, length);
1675         BUG_ON(err);
1676
1677         return *(u32 *)desc.ctx;
1678 }
1679
1680 #ifdef __KERNEL__
1681
1682 /* hash info structure used by the directory hash */
1683 struct dx_hash_info
1684 {
1685         u32             hash;
1686         u32             minor_hash;
1687         int             hash_version;
1688         u32             *seed;
1689 };
1690
1691
1692 /* 32 and 64 bit signed EOF for dx directories */
1693 #define EXT4_HTREE_EOF_32BIT   ((1UL  << (32 - 1)) - 1)
1694 #define EXT4_HTREE_EOF_64BIT   ((1ULL << (64 - 1)) - 1)
1695
1696
1697 /*
1698  * Control parameters used by ext4_htree_next_block
1699  */
1700 #define HASH_NB_ALWAYS          1
1701
1702
1703 /*
1704  * Describe an inode's exact location on disk and in memory
1705  */
1706 struct ext4_iloc
1707 {
1708         struct buffer_head *bh;
1709         unsigned long offset;
1710         ext4_group_t block_group;
1711 };
1712
1713 static inline struct ext4_inode *ext4_raw_inode(struct ext4_iloc *iloc)
1714 {
1715         return (struct ext4_inode *) (iloc->bh->b_data + iloc->offset);
1716 }
1717
1718 /*
1719  * This structure is stuffed into the struct file's private_data field
1720  * for directories.  It is where we put information so that we can do
1721  * readdir operations in hash tree order.
1722  */
1723 struct dir_private_info {
1724         struct rb_root  root;
1725         struct rb_node  *curr_node;
1726         struct fname    *extra_fname;
1727         loff_t          last_pos;
1728         __u32           curr_hash;
1729         __u32           curr_minor_hash;
1730         __u32           next_hash;
1731 };
1732
1733 /* calculate the first block number of the group */
1734 static inline ext4_fsblk_t
1735 ext4_group_first_block_no(struct super_block *sb, ext4_group_t group_no)
1736 {
1737         return group_no * (ext4_fsblk_t)EXT4_BLOCKS_PER_GROUP(sb) +
1738                 le32_to_cpu(EXT4_SB(sb)->s_es->s_first_data_block);
1739 }
1740
1741 /*
1742  * Special error return code only used by dx_probe() and its callers.
1743  */
1744 #define ERR_BAD_DX_DIR  -75000
1745
1746 void ext4_get_group_no_and_offset(struct super_block *sb, ext4_fsblk_t blocknr,
1747                         ext4_group_t *blockgrpp, ext4_grpblk_t *offsetp);
1748
1749 /*
1750  * Timeout and state flag for lazy initialization inode thread.
1751  */
1752 #define EXT4_DEF_LI_WAIT_MULT                   10
1753 #define EXT4_DEF_LI_MAX_START_DELAY             5
1754 #define EXT4_LAZYINIT_QUIT                      0x0001
1755 #define EXT4_LAZYINIT_RUNNING                   0x0002
1756
1757 /*
1758  * Lazy inode table initialization info
1759  */
1760 struct ext4_lazy_init {
1761         unsigned long           li_state;
1762         struct list_head        li_request_list;
1763         struct mutex            li_list_mtx;
1764 };
1765
1766 struct ext4_li_request {
1767         struct super_block      *lr_super;
1768         struct ext4_sb_info     *lr_sbi;
1769         ext4_group_t            lr_next_group;
1770         struct list_head        lr_request;
1771         unsigned long           lr_next_sched;
1772         unsigned long           lr_timeout;
1773 };
1774
1775 struct ext4_features {
1776         struct kobject f_kobj;
1777         struct completion f_kobj_unregister;
1778 };
1779
1780 /*
1781  * This structure will be used for multiple mount protection. It will be
1782  * written into the block number saved in the s_mmp_block field in the
1783  * superblock. Programs that check MMP should assume that if
1784  * SEQ_FSCK (or any unknown code above SEQ_MAX) is present then it is NOT safe
1785  * to use the filesystem, regardless of how old the timestamp is.
1786  */
1787 #define EXT4_MMP_MAGIC     0x004D4D50U /* ASCII for MMP */
1788 #define EXT4_MMP_SEQ_CLEAN 0xFF4D4D50U /* mmp_seq value for clean unmount */
1789 #define EXT4_MMP_SEQ_FSCK  0xE24D4D50U /* mmp_seq value when being fscked */
1790 #define EXT4_MMP_SEQ_MAX   0xE24D4D4FU /* maximum valid mmp_seq value */
1791
1792 struct mmp_struct {
1793         __le32  mmp_magic;              /* Magic number for MMP */
1794         __le32  mmp_seq;                /* Sequence no. updated periodically */
1795
1796         /*
1797          * mmp_time, mmp_nodename & mmp_bdevname are only used for information
1798          * purposes and do not affect the correctness of the algorithm
1799          */
1800         __le64  mmp_time;               /* Time last updated */
1801         char    mmp_nodename[64];       /* Node which last updated MMP block */
1802         char    mmp_bdevname[32];       /* Bdev which last updated MMP block */
1803
1804         /*
1805          * mmp_check_interval is used to verify if the MMP block has been
1806          * updated on the block device. The value is updated based on the
1807          * maximum time to write the MMP block during an update cycle.
1808          */
1809         __le16  mmp_check_interval;
1810
1811         __le16  mmp_pad1;
1812         __le32  mmp_pad2[226];
1813         __le32  mmp_checksum;           /* crc32c(uuid+mmp_block) */
1814 };
1815
1816 /* arguments passed to the mmp thread */
1817 struct mmpd_data {
1818         struct buffer_head *bh; /* bh from initial read_mmp_block() */
1819         struct super_block *sb;  /* super block of the fs */
1820 };
1821
1822 /*
1823  * Check interval multiplier
1824  * The MMP block is written every update interval and initially checked every
1825  * update interval x the multiplier (the value is then adapted based on the
1826  * write latency). The reason is that writes can be delayed under load and we
1827  * don't want readers to incorrectly assume that the filesystem is no longer
1828  * in use.
1829  */
1830 #define EXT4_MMP_CHECK_MULT             2UL
1831
1832 /*
1833  * Minimum interval for MMP checking in seconds.
1834  */
1835 #define EXT4_MMP_MIN_CHECK_INTERVAL     5UL
1836
1837 /*
1838  * Maximum interval for MMP checking in seconds.
1839  */
1840 #define EXT4_MMP_MAX_CHECK_INTERVAL     300UL
1841
1842 /*
1843  * Function prototypes
1844  */
1845
1846 /*
1847  * Ok, these declarations are also in <linux/kernel.h> but none of the
1848  * ext4 source programs needs to include it so they are duplicated here.
1849  */
1850 # define NORET_TYPE     /**/
1851 # define ATTRIB_NORET   __attribute__((noreturn))
1852 # define NORET_AND      noreturn,
1853
1854 /* bitmap.c */
1855 extern unsigned int ext4_count_free(struct buffer_head *, unsigned);
1856 void ext4_inode_bitmap_csum_set(struct super_block *sb, ext4_group_t group,
1857                                 struct ext4_group_desc *gdp,
1858                                 struct buffer_head *bh, int sz);
1859 int ext4_inode_bitmap_csum_verify(struct super_block *sb, ext4_group_t group,
1860                                   struct ext4_group_desc *gdp,
1861                                   struct buffer_head *bh, int sz);
1862 void ext4_block_bitmap_csum_set(struct super_block *sb, ext4_group_t group,
1863                                 struct ext4_group_desc *gdp,
1864                                 struct buffer_head *bh, int sz);
1865 int ext4_block_bitmap_csum_verify(struct super_block *sb, ext4_group_t group,
1866                                   struct ext4_group_desc *gdp,
1867                                   struct buffer_head *bh, int sz);
1868
1869 /* balloc.c */
1870 extern void ext4_validate_block_bitmap(struct super_block *sb,
1871                                        struct ext4_group_desc *desc,
1872                                        unsigned int block_group,
1873                                        struct buffer_head *bh);
1874 extern unsigned int ext4_block_group(struct super_block *sb,
1875                         ext4_fsblk_t blocknr);
1876 extern ext4_grpblk_t ext4_block_group_offset(struct super_block *sb,
1877                         ext4_fsblk_t blocknr);
1878 extern int ext4_bg_has_super(struct super_block *sb, ext4_group_t group);
1879 extern unsigned long ext4_bg_num_gdb(struct super_block *sb,
1880                         ext4_group_t group);
1881 extern ext4_fsblk_t ext4_new_meta_blocks(handle_t *handle, struct inode *inode,
1882                                          ext4_fsblk_t goal,
1883                                          unsigned int flags,
1884                                          unsigned long *count,
1885                                          int *errp);
1886 extern int ext4_claim_free_clusters(struct ext4_sb_info *sbi,
1887                                     s64 nclusters, unsigned int flags);
1888 extern ext4_fsblk_t ext4_count_free_clusters(struct super_block *);
1889 extern void ext4_check_blocks_bitmap(struct super_block *);
1890 extern struct ext4_group_desc * ext4_get_group_desc(struct super_block * sb,
1891                                                     ext4_group_t block_group,
1892                                                     struct buffer_head ** bh);
1893 extern int ext4_should_retry_alloc(struct super_block *sb, int *retries);
1894
1895 extern struct buffer_head *ext4_read_block_bitmap_nowait(struct super_block *sb,
1896                                                 ext4_group_t block_group);
1897 extern int ext4_wait_block_bitmap(struct super_block *sb,
1898                                   ext4_group_t block_group,
1899                                   struct buffer_head *bh);
1900 extern struct buffer_head *ext4_read_block_bitmap(struct super_block *sb,
1901                                                   ext4_group_t block_group);
1902 extern void ext4_init_block_bitmap(struct super_block *sb,
1903                                    struct buffer_head *bh,
1904                                    ext4_group_t group,
1905                                    struct ext4_group_desc *desc);
1906 extern unsigned ext4_free_clusters_after_init(struct super_block *sb,
1907                                               ext4_group_t block_group,
1908                                               struct ext4_group_desc *gdp);
1909 extern unsigned ext4_num_overhead_clusters(struct super_block *sb,
1910                                            ext4_group_t block_group,
1911                                            struct ext4_group_desc *gdp);
1912 ext4_fsblk_t ext4_inode_to_goal_block(struct inode *);
1913
1914 /* dir.c */
1915 extern int __ext4_check_dir_entry(const char *, unsigned int, struct inode *,
1916                                   struct file *,
1917                                   struct ext4_dir_entry_2 *,
1918                                   struct buffer_head *, unsigned int);
1919 #define ext4_check_dir_entry(dir, filp, de, bh, offset)                 \
1920         unlikely(__ext4_check_dir_entry(__func__, __LINE__, (dir), (filp), \
1921                                         (de), (bh), (offset)))
1922 extern int ext4_htree_store_dirent(struct file *dir_file, __u32 hash,
1923                                     __u32 minor_hash,
1924                                     struct ext4_dir_entry_2 *dirent);
1925 extern void ext4_htree_free_dir_info(struct dir_private_info *p);
1926
1927 /* fsync.c */
1928 extern int ext4_sync_file(struct file *, loff_t, loff_t, int);
1929 extern int ext4_flush_completed_IO(struct inode *);
1930
1931 /* hash.c */
1932 extern int ext4fs_dirhash(const char *name, int len, struct
1933                           dx_hash_info *hinfo);
1934
1935 /* ialloc.c */
1936 extern struct inode *ext4_new_inode(handle_t *, struct inode *, umode_t,
1937                                     const struct qstr *qstr, __u32 goal,
1938                                     uid_t *owner);
1939 extern void ext4_free_inode(handle_t *, struct inode *);
1940 extern struct inode * ext4_orphan_get(struct super_block *, unsigned long);
1941 extern unsigned long ext4_count_free_inodes(struct super_block *);
1942 extern unsigned long ext4_count_dirs(struct super_block *);
1943 extern void ext4_check_inodes_bitmap(struct super_block *);
1944 extern void ext4_mark_bitmap_end(int start_bit, int end_bit, char *bitmap);
1945 extern int ext4_init_inode_table(struct super_block *sb,
1946                                  ext4_group_t group, int barrier);
1947 extern void ext4_end_bitmap_read(struct buffer_head *bh, int uptodate);
1948
1949 /* mballoc.c */
1950 extern long ext4_mb_stats;
1951 extern long ext4_mb_max_to_scan;
1952 extern int ext4_mb_init(struct super_block *);
1953 extern int ext4_mb_release(struct super_block *);
1954 extern ext4_fsblk_t ext4_mb_new_blocks(handle_t *,
1955                                 struct ext4_allocation_request *, int *);
1956 extern int ext4_mb_reserve_blocks(struct super_block *, int);
1957 extern void ext4_discard_preallocations(struct inode *);
1958 extern int __init ext4_init_mballoc(void);
1959 extern void ext4_exit_mballoc(void);
1960 extern void ext4_free_blocks(handle_t *handle, struct inode *inode,
1961                              struct buffer_head *bh, ext4_fsblk_t block,
1962                              unsigned long count, int flags);
1963 extern int ext4_mb_add_groupinfo(struct super_block *sb,
1964                 ext4_group_t i, struct ext4_group_desc *desc);
1965 extern int ext4_group_add_blocks(handle_t *handle, struct super_block *sb,
1966                                 ext4_fsblk_t block, unsigned long count);
1967 extern int ext4_trim_fs(struct super_block *, struct fstrim_range *);
1968
1969 /* inode.c */
1970 struct buffer_head *ext4_getblk(handle_t *, struct inode *,
1971                                                 ext4_lblk_t, int, int *);
1972 struct buffer_head *ext4_bread(handle_t *, struct inode *,
1973                                                 ext4_lblk_t, int, int *);
1974 int ext4_get_block(struct inode *inode, sector_t iblock,
1975                                 struct buffer_head *bh_result, int create);
1976
1977 extern struct inode *ext4_iget(struct super_block *, unsigned long);
1978 extern int  ext4_write_inode(struct inode *, struct writeback_control *);
1979 extern int  ext4_setattr(struct dentry *, struct iattr *);
1980 extern int  ext4_getattr(struct vfsmount *mnt, struct dentry *dentry,
1981                                 struct kstat *stat);
1982 extern void ext4_evict_inode(struct inode *);
1983 extern void ext4_clear_inode(struct inode *);
1984 extern int  ext4_sync_inode(handle_t *, struct inode *);
1985 extern void ext4_dirty_inode(struct inode *, int);
1986 extern int ext4_change_inode_journal_flag(struct inode *, int);
1987 extern int ext4_get_inode_loc(struct inode *, struct ext4_iloc *);
1988 extern int ext4_can_truncate(struct inode *inode);
1989 extern void ext4_truncate(struct inode *);
1990 extern int ext4_punch_hole(struct file *file, loff_t offset, loff_t length);
1991 extern int ext4_truncate_restart_trans(handle_t *, struct inode *, int nblocks);
1992 extern void ext4_set_inode_flags(struct inode *);
1993 extern void ext4_get_inode_flags(struct ext4_inode_info *);
1994 extern int ext4_alloc_da_blocks(struct inode *inode);
1995 extern void ext4_set_aops(struct inode *inode);
1996 extern int ext4_writepage_trans_blocks(struct inode *);
1997 extern int ext4_chunk_trans_blocks(struct inode *, int nrblocks);
1998 extern int ext4_discard_partial_page_buffers(handle_t *handle,
1999                 struct address_space *mapping, loff_t from,
2000                 loff_t length, int flags);
2001 extern int ext4_page_mkwrite(struct vm_area_struct *vma, struct vm_fault *vmf);
2002 extern qsize_t *ext4_get_reserved_space(struct inode *inode);
2003 extern void ext4_da_update_reserve_space(struct inode *inode,
2004                                         int used, int quota_claim);
2005
2006 /* indirect.c */
2007 extern int ext4_ind_map_blocks(handle_t *handle, struct inode *inode,
2008                                 struct ext4_map_blocks *map, int flags);
2009 extern ssize_t ext4_ind_direct_IO(int rw, struct kiocb *iocb,
2010                                 const struct iovec *iov, loff_t offset,
2011                                 unsigned long nr_segs);
2012 extern int ext4_ind_calc_metadata_amount(struct inode *inode, sector_t lblock);
2013 extern int ext4_ind_trans_blocks(struct inode *inode, int nrblocks, int chunk);
2014 extern void ext4_ind_truncate(struct inode *inode);
2015
2016 /* ioctl.c */
2017 extern long ext4_ioctl(struct file *, unsigned int, unsigned long);
2018 extern long ext4_compat_ioctl(struct file *, unsigned int, unsigned long);
2019
2020 /* migrate.c */
2021 extern int ext4_ext_migrate(struct inode *);
2022
2023 /* namei.c */
2024 extern int ext4_dirent_csum_verify(struct inode *inode,
2025                                    struct ext4_dir_entry *dirent);
2026 extern int ext4_orphan_add(handle_t *, struct inode *);
2027 extern int ext4_orphan_del(handle_t *, struct inode *);
2028 extern int ext4_htree_fill_tree(struct file *dir_file, __u32 start_hash,
2029                                 __u32 start_minor_hash, __u32 *next_hash);
2030
2031 /* resize.c */
2032 extern int ext4_group_add(struct super_block *sb,
2033                                 struct ext4_new_group_data *input);
2034 extern int ext4_group_extend(struct super_block *sb,
2035                                 struct ext4_super_block *es,
2036                                 ext4_fsblk_t n_blocks_count);
2037 extern int ext4_resize_fs(struct super_block *sb, ext4_fsblk_t n_blocks_count);
2038
2039 /* super.c */
2040 extern int ext4_superblock_csum_verify(struct super_block *sb,
2041                                        struct ext4_super_block *es);
2042 extern void ext4_superblock_csum_set(struct super_block *sb,
2043                                      struct ext4_super_block *es);
2044 extern void *ext4_kvmalloc(size_t size, gfp_t flags);
2045 extern void *ext4_kvzalloc(size_t size, gfp_t flags);
2046 extern void ext4_kvfree(void *ptr);
2047 extern __printf(4, 5)
2048 void __ext4_error(struct super_block *, const char *, unsigned int,
2049                   const char *, ...);
2050 #define ext4_error(sb, message...)      __ext4_error(sb, __func__,      \
2051                                                      __LINE__, ## message)
2052 extern __printf(5, 6)
2053 void ext4_error_inode(struct inode *, const char *, unsigned int, ext4_fsblk_t,
2054                       const char *, ...);
2055 extern __printf(5, 6)
2056 void ext4_error_file(struct file *, const char *, unsigned int, ext4_fsblk_t,
2057                      const char *, ...);
2058 extern void __ext4_std_error(struct super_block *, const char *,
2059                              unsigned int, int);
2060 extern __printf(4, 5)
2061 void __ext4_abort(struct super_block *, const char *, unsigned int,
2062                   const char *, ...);
2063 #define ext4_abort(sb, message...)      __ext4_abort(sb, __func__, \
2064                                                        __LINE__, ## message)
2065 extern __printf(4, 5)
2066 void __ext4_warning(struct super_block *, const char *, unsigned int,
2067                     const char *, ...);
2068 #define ext4_warning(sb, message...)    __ext4_warning(sb, __func__, \
2069                                                        __LINE__, ## message)
2070 extern __printf(3, 4)
2071 void ext4_msg(struct super_block *, const char *, const char *, ...);
2072 extern void __dump_mmp_msg(struct super_block *, struct mmp_struct *mmp,
2073                            const char *, unsigned int, const char *);
2074 #define dump_mmp_msg(sb, mmp, msg)      __dump_mmp_msg(sb, mmp, __func__, \
2075                                                        __LINE__, msg)
2076 extern __printf(7, 8)
2077 void __ext4_grp_locked_error(const char *, unsigned int,
2078                              struct super_block *, ext4_group_t,
2079                              unsigned long, ext4_fsblk_t,
2080                              const char *, ...);
2081 #define ext4_grp_locked_error(sb, grp, message...) \
2082         __ext4_grp_locked_error(__func__, __LINE__, (sb), (grp), ## message)
2083 extern void ext4_update_dynamic_rev(struct super_block *sb);
2084 extern int ext4_update_compat_feature(handle_t *handle, struct super_block *sb,
2085                                         __u32 compat);
2086 extern int ext4_update_rocompat_feature(handle_t *handle,
2087                                         struct super_block *sb, __u32 rocompat);
2088 extern int ext4_update_incompat_feature(handle_t *handle,
2089                                         struct super_block *sb, __u32 incompat);
2090 extern ext4_fsblk_t ext4_block_bitmap(struct super_block *sb,
2091                                       struct ext4_group_desc *bg);
2092 extern ext4_fsblk_t ext4_inode_bitmap(struct super_block *sb,
2093                                       struct ext4_group_desc *bg);
2094 extern ext4_fsblk_t ext4_inode_table(struct super_block *sb,
2095                                      struct ext4_group_desc *bg);
2096 extern __u32 ext4_free_group_clusters(struct super_block *sb,
2097                                       struct ext4_group_desc *bg);
2098 extern __u32 ext4_free_inodes_count(struct super_block *sb,
2099                                  struct ext4_group_desc *bg);
2100 extern __u32 ext4_used_dirs_count(struct super_block *sb,
2101                                 struct ext4_group_desc *bg);
2102 extern __u32 ext4_itable_unused_count(struct super_block *sb,
2103                                    struct ext4_group_desc *bg);
2104 extern void ext4_block_bitmap_set(struct super_block *sb,
2105                                   struct ext4_group_desc *bg, ext4_fsblk_t blk);
2106 extern void ext4_inode_bitmap_set(struct super_block *sb,
2107                                   struct ext4_group_desc *bg, ext4_fsblk_t blk);
2108 extern void ext4_inode_table_set(struct super_block *sb,
2109                                  struct ext4_group_desc *bg, ext4_fsblk_t blk);
2110 extern void ext4_free_group_clusters_set(struct super_block *sb,
2111                                          struct ext4_group_desc *bg,
2112                                          __u32 count);
2113 extern void ext4_free_inodes_set(struct super_block *sb,
2114                                 struct ext4_group_desc *bg, __u32 count);
2115 extern void ext4_used_dirs_set(struct super_block *sb,
2116                                 struct ext4_group_desc *bg, __u32 count);
2117 extern void ext4_itable_unused_set(struct super_block *sb,
2118                                    struct ext4_group_desc *bg, __u32 count);
2119 extern int ext4_group_desc_csum_verify(struct super_block *sb, __u32 group,
2120                                        struct ext4_group_desc *gdp);
2121 extern void ext4_group_desc_csum_set(struct super_block *sb, __u32 group,
2122                                      struct ext4_group_desc *gdp);
2123
2124 static inline int ext4_has_group_desc_csum(struct super_block *sb)
2125 {
2126         return EXT4_HAS_RO_COMPAT_FEATURE(sb,
2127                                           EXT4_FEATURE_RO_COMPAT_GDT_CSUM |
2128                                           EXT4_FEATURE_RO_COMPAT_METADATA_CSUM);
2129 }
2130
2131 static inline ext4_fsblk_t ext4_blocks_count(struct ext4_super_block *es)
2132 {
2133         return ((ext4_fsblk_t)le32_to_cpu(es->s_blocks_count_hi) << 32) |
2134                 le32_to_cpu(es->s_blocks_count_lo);
2135 }
2136
2137 static inline ext4_fsblk_t ext4_r_blocks_count(struct ext4_super_block *es)
2138 {
2139         return ((ext4_fsblk_t)le32_to_cpu(es->s_r_blocks_count_hi) << 32) |
2140                 le32_to_cpu(es->s_r_blocks_count_lo);
2141 }
2142
2143 static inline ext4_fsblk_t ext4_free_blocks_count(struct ext4_super_block *es)
2144 {
2145         return ((ext4_fsblk_t)le32_to_cpu(es->s_free_blocks_count_hi) << 32) |
2146                 le32_to_cpu(es->s_free_blocks_count_lo);
2147 }
2148
2149 static inline void ext4_blocks_count_set(struct ext4_super_block *es,
2150                                          ext4_fsblk_t blk)
2151 {
2152         es->s_blocks_count_lo = cpu_to_le32((u32)blk);
2153         es->s_blocks_count_hi = cpu_to_le32(blk >> 32);
2154 }
2155
2156 static inline void ext4_free_blocks_count_set(struct ext4_super_block *es,
2157                                               ext4_fsblk_t blk)
2158 {
2159         es->s_free_blocks_count_lo = cpu_to_le32((u32)blk);
2160         es->s_free_blocks_count_hi = cpu_to_le32(blk >> 32);
2161 }
2162
2163 static inline void ext4_r_blocks_count_set(struct ext4_super_block *es,
2164                                            ext4_fsblk_t blk)
2165 {
2166         es->s_r_blocks_count_lo = cpu_to_le32((u32)blk);
2167         es->s_r_blocks_count_hi = cpu_to_le32(blk >> 32);
2168 }
2169
2170 static inline loff_t ext4_isize(struct ext4_inode *raw_inode)
2171 {
2172         if (S_ISREG(le16_to_cpu(raw_inode->i_mode)))
2173                 return ((loff_t)le32_to_cpu(raw_inode->i_size_high) << 32) |
2174                         le32_to_cpu(raw_inode->i_size_lo);
2175         else
2176                 return (loff_t) le32_to_cpu(raw_inode->i_size_lo);
2177 }
2178
2179 static inline void ext4_isize_set(struct ext4_inode *raw_inode, loff_t i_size)
2180 {
2181         raw_inode->i_size_lo = cpu_to_le32(i_size);
2182         raw_inode->i_size_high = cpu_to_le32(i_size >> 32);
2183 }
2184
2185 static inline
2186 struct ext4_group_info *ext4_get_group_info(struct super_block *sb,
2187                                             ext4_group_t group)
2188 {
2189          struct ext4_group_info ***grp_info;
2190          long indexv, indexh;
2191          grp_info = EXT4_SB(sb)->s_group_info;
2192          indexv = group >> (EXT4_DESC_PER_BLOCK_BITS(sb));
2193          indexh = group & ((EXT4_DESC_PER_BLOCK(sb)) - 1);
2194          return grp_info[indexv][indexh];
2195 }
2196
2197 /*
2198  * Reading s_groups_count requires using smp_rmb() afterwards.  See
2199  * the locking protocol documented in the comments of ext4_group_add()
2200  * in resize.c
2201  */
2202 static inline ext4_group_t ext4_get_groups_count(struct super_block *sb)
2203 {
2204         ext4_group_t    ngroups = EXT4_SB(sb)->s_groups_count;
2205
2206         smp_rmb();
2207         return ngroups;
2208 }
2209
2210 static inline ext4_group_t ext4_flex_group(struct ext4_sb_info *sbi,
2211                                              ext4_group_t block_group)
2212 {
2213         return block_group >> sbi->s_log_groups_per_flex;
2214 }
2215
2216 static inline unsigned int ext4_flex_bg_size(struct ext4_sb_info *sbi)
2217 {
2218         return 1 << sbi->s_log_groups_per_flex;
2219 }
2220
2221 #define ext4_std_error(sb, errno)                               \
2222 do {                                                            \
2223         if ((errno))                                            \
2224                 __ext4_std_error((sb), __func__, __LINE__, (errno));    \
2225 } while (0)
2226
2227 #ifdef CONFIG_SMP
2228 /* Each CPU can accumulate percpu_counter_batch clusters in their local
2229  * counters. So we need to make sure we have free clusters more
2230  * than percpu_counter_batch  * nr_cpu_ids. Also add a window of 4 times.
2231  */
2232 #define EXT4_FREECLUSTERS_WATERMARK (4 * (percpu_counter_batch * nr_cpu_ids))
2233 #else
2234 #define EXT4_FREECLUSTERS_WATERMARK 0
2235 #endif
2236
2237 static inline void ext4_update_i_disksize(struct inode *inode, loff_t newsize)
2238 {
2239         /*
2240          * XXX: replace with spinlock if seen contended -bzzz
2241          */
2242         down_write(&EXT4_I(inode)->i_data_sem);
2243         if (newsize > EXT4_I(inode)->i_disksize)
2244                 EXT4_I(inode)->i_disksize = newsize;
2245         up_write(&EXT4_I(inode)->i_data_sem);
2246         return ;
2247 }
2248
2249 struct ext4_group_info {
2250         unsigned long   bb_state;
2251         struct rb_root  bb_free_root;
2252         ext4_grpblk_t   bb_first_free;  /* first free block */
2253         ext4_grpblk_t   bb_free;        /* total free blocks */
2254         ext4_grpblk_t   bb_fragments;   /* nr of freespace fragments */
2255         ext4_grpblk_t   bb_largest_free_order;/* order of largest frag in BG */
2256         struct          list_head bb_prealloc_list;
2257 #ifdef DOUBLE_CHECK
2258         void            *bb_bitmap;
2259 #endif
2260         struct rw_semaphore alloc_sem;
2261         ext4_grpblk_t   bb_counters[];  /* Nr of free power-of-two-block
2262                                          * regions, index is order.
2263                                          * bb_counters[3] = 5 means
2264                                          * 5 free 8-block regions. */
2265 };
2266
2267 #define EXT4_GROUP_INFO_NEED_INIT_BIT           0
2268 #define EXT4_GROUP_INFO_WAS_TRIMMED_BIT         1
2269
2270 #define EXT4_MB_GRP_NEED_INIT(grp)      \
2271         (test_bit(EXT4_GROUP_INFO_NEED_INIT_BIT, &((grp)->bb_state)))
2272
2273 #define EXT4_MB_GRP_WAS_TRIMMED(grp)    \
2274         (test_bit(EXT4_GROUP_INFO_WAS_TRIMMED_BIT, &((grp)->bb_state)))
2275 #define EXT4_MB_GRP_SET_TRIMMED(grp)    \
2276         (set_bit(EXT4_GROUP_INFO_WAS_TRIMMED_BIT, &((grp)->bb_state)))
2277 #define EXT4_MB_GRP_CLEAR_TRIMMED(grp)  \
2278         (clear_bit(EXT4_GROUP_INFO_WAS_TRIMMED_BIT, &((grp)->bb_state)))
2279
2280 #define EXT4_MAX_CONTENTION             8
2281 #define EXT4_CONTENTION_THRESHOLD       2
2282
2283 static inline spinlock_t *ext4_group_lock_ptr(struct super_block *sb,
2284                                               ext4_group_t group)
2285 {
2286         return bgl_lock_ptr(EXT4_SB(sb)->s_blockgroup_lock, group);
2287 }
2288
2289 /*
2290  * Returns true if the filesystem is busy enough that attempts to
2291  * access the block group locks has run into contention.
2292  */
2293 static inline int ext4_fs_is_busy(struct ext4_sb_info *sbi)
2294 {
2295         return (atomic_read(&sbi->s_lock_busy) > EXT4_CONTENTION_THRESHOLD);
2296 }
2297
2298 static inline void ext4_lock_group(struct super_block *sb, ext4_group_t group)
2299 {
2300         spinlock_t *lock = ext4_group_lock_ptr(sb, group);
2301         if (spin_trylock(lock))
2302                 /*
2303                  * We're able to grab the lock right away, so drop the
2304                  * lock contention counter.
2305                  */
2306                 atomic_add_unless(&EXT4_SB(sb)->s_lock_busy, -1, 0);
2307         else {
2308                 /*
2309                  * The lock is busy, so bump the contention counter,
2310                  * and then wait on the spin lock.
2311                  */
2312                 atomic_add_unless(&EXT4_SB(sb)->s_lock_busy, 1,
2313                                   EXT4_MAX_CONTENTION);
2314                 spin_lock(lock);
2315         }
2316 }
2317
2318 static inline void ext4_unlock_group(struct super_block *sb,
2319                                         ext4_group_t group)
2320 {
2321         spin_unlock(ext4_group_lock_ptr(sb, group));
2322 }
2323
2324 static inline void ext4_mark_super_dirty(struct super_block *sb)
2325 {
2326         struct ext4_super_block *es = EXT4_SB(sb)->s_es;
2327
2328         ext4_superblock_csum_set(sb, es);
2329         if (EXT4_SB(sb)->s_journal == NULL)
2330                 sb->s_dirt =1;
2331 }
2332
2333 /*
2334  * Block validity checking
2335  */
2336 #define ext4_check_indirect_blockref(inode, bh)                         \
2337         ext4_check_blockref(__func__, __LINE__, inode,                  \
2338                             (__le32 *)(bh)->b_data,                     \
2339                             EXT4_ADDR_PER_BLOCK((inode)->i_sb))
2340
2341 #define ext4_ind_check_inode(inode)                                     \
2342         ext4_check_blockref(__func__, __LINE__, inode,                  \
2343                             EXT4_I(inode)->i_data,                      \
2344                             EXT4_NDIR_BLOCKS)
2345
2346 /*
2347  * Inodes and files operations
2348  */
2349
2350 /* dir.c */
2351 extern const struct file_operations ext4_dir_operations;
2352
2353 /* file.c */
2354 extern const struct inode_operations ext4_file_inode_operations;
2355 extern const struct file_operations ext4_file_operations;
2356 extern loff_t ext4_llseek(struct file *file, loff_t offset, int origin);
2357
2358 /* namei.c */
2359 extern const struct inode_operations ext4_dir_inode_operations;
2360 extern const struct inode_operations ext4_special_inode_operations;
2361 extern struct dentry *ext4_get_parent(struct dentry *child);
2362
2363 /* symlink.c */
2364 extern const struct inode_operations ext4_symlink_inode_operations;
2365 extern const struct inode_operations ext4_fast_symlink_inode_operations;
2366
2367 /* block_validity */
2368 extern void ext4_release_system_zone(struct super_block *sb);
2369 extern int ext4_setup_system_zone(struct super_block *sb);
2370 extern int __init ext4_init_system_zone(void);
2371 extern void ext4_exit_system_zone(void);
2372 extern int ext4_data_block_valid(struct ext4_sb_info *sbi,
2373                                  ext4_fsblk_t start_blk,
2374                                  unsigned int count);
2375 extern int ext4_check_blockref(const char *, unsigned int,
2376                                struct inode *, __le32 *, unsigned int);
2377
2378 /* extents.c */
2379 extern int ext4_ext_tree_init(handle_t *handle, struct inode *);
2380 extern int ext4_ext_writepage_trans_blocks(struct inode *, int);
2381 extern int ext4_ext_index_trans_blocks(struct inode *inode, int nrblocks,
2382                                        int chunk);
2383 extern int ext4_ext_map_blocks(handle_t *handle, struct inode *inode,
2384                                struct ext4_map_blocks *map, int flags);
2385 extern void ext4_ext_truncate(struct inode *);
2386 extern int ext4_ext_punch_hole(struct file *file, loff_t offset,
2387                                 loff_t length);
2388 extern void ext4_ext_init(struct super_block *);
2389 extern void ext4_ext_release(struct super_block *);
2390 extern long ext4_fallocate(struct file *file, int mode, loff_t offset,
2391                           loff_t len);
2392 extern int ext4_convert_unwritten_extents(struct inode *inode, loff_t offset,
2393                           ssize_t len);
2394 extern int ext4_map_blocks(handle_t *handle, struct inode *inode,
2395                            struct ext4_map_blocks *map, int flags);
2396 extern int ext4_fiemap(struct inode *inode, struct fiemap_extent_info *fieinfo,
2397                         __u64 start, __u64 len);
2398 /* move_extent.c */
2399 extern int ext4_move_extents(struct file *o_filp, struct file *d_filp,
2400                              __u64 start_orig, __u64 start_donor,
2401                              __u64 len, __u64 *moved_len);
2402
2403 /* page-io.c */
2404 extern int __init ext4_init_pageio(void);
2405 extern void ext4_exit_pageio(void);
2406 extern void ext4_ioend_wait(struct inode *);
2407 extern void ext4_free_io_end(ext4_io_end_t *io);
2408 extern ext4_io_end_t *ext4_init_io_end(struct inode *inode, gfp_t flags);
2409 extern int ext4_end_io_nolock(ext4_io_end_t *io);
2410 extern void ext4_io_submit(struct ext4_io_submit *io);
2411 extern int ext4_bio_write_page(struct ext4_io_submit *io,
2412                                struct page *page,
2413                                int len,
2414                                struct writeback_control *wbc);
2415
2416 /* mmp.c */
2417 extern int ext4_multi_mount_protect(struct super_block *, ext4_fsblk_t);
2418 extern void ext4_mmp_csum_set(struct super_block *sb, struct mmp_struct *mmp);
2419 extern int ext4_mmp_csum_verify(struct super_block *sb,
2420                                 struct mmp_struct *mmp);
2421
2422 /* BH_Uninit flag: blocks are allocated but uninitialized on disk */
2423 enum ext4_state_bits {
2424         BH_Uninit       /* blocks are allocated but uninitialized on disk */
2425           = BH_JBDPrivateStart,
2426         BH_AllocFromCluster,    /* allocated blocks were part of already
2427                                  * allocated cluster. Note that this flag will
2428                                  * never, ever appear in a buffer_head's state
2429                                  * flag. See EXT4_MAP_FROM_CLUSTER to see where
2430                                  * this is used. */
2431         BH_Da_Mapped,   /* Delayed allocated block that now has a mapping. This
2432                          * flag is set when ext4_map_blocks is called on a
2433                          * delayed allocated block to get its real mapping. */
2434 };
2435
2436 BUFFER_FNS(Uninit, uninit)
2437 TAS_BUFFER_FNS(Uninit, uninit)
2438 BUFFER_FNS(Da_Mapped, da_mapped)
2439
2440 /*
2441  * Add new method to test wether block and inode bitmaps are properly
2442  * initialized. With uninit_bg reading the block from disk is not enough
2443  * to mark the bitmap uptodate. We need to also zero-out the bitmap
2444  */
2445 #define BH_BITMAP_UPTODATE BH_JBDPrivateStart
2446
2447 static inline int bitmap_uptodate(struct buffer_head *bh)
2448 {
2449         return (buffer_uptodate(bh) &&
2450                         test_bit(BH_BITMAP_UPTODATE, &(bh)->b_state));
2451 }
2452 static inline void set_bitmap_uptodate(struct buffer_head *bh)
2453 {
2454         set_bit(BH_BITMAP_UPTODATE, &(bh)->b_state);
2455 }
2456
2457 #define in_range(b, first, len) ((b) >= (first) && (b) <= (first) + (len) - 1)
2458
2459 /* For ioend & aio unwritten conversion wait queues */
2460 #define EXT4_WQ_HASH_SZ         37
2461 #define ext4_ioend_wq(v)   (&ext4__ioend_wq[((unsigned long)(v)) %\
2462                                             EXT4_WQ_HASH_SZ])
2463 #define ext4_aio_mutex(v)  (&ext4__aio_mutex[((unsigned long)(v)) %\
2464                                              EXT4_WQ_HASH_SZ])
2465 extern wait_queue_head_t ext4__ioend_wq[EXT4_WQ_HASH_SZ];
2466 extern struct mutex ext4__aio_mutex[EXT4_WQ_HASH_SZ];
2467
2468 #define EXT4_RESIZING   0
2469 extern int ext4_resize_begin(struct super_block *sb);
2470 extern void ext4_resize_end(struct super_block *sb);
2471
2472 #endif  /* __KERNEL__ */
2473
2474 #include "ext4_extents.h"
2475
2476 #endif  /* _EXT4_H */