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 <linux/ratelimit.h>
  33 #include <crypto/hash.h>
  34 #include <linux/falloc.h>
  35 #ifdef __KERNEL__
  36 #include <linux/compat.h>
  37 #endif
  38
  39 /*
  40  * The fourth extended filesystem constants/structures
  41  */
  42
  43 /*
  44  * Define EXT4FS_DEBUG to produce debug messages
  45  */
  46 #undef EXT4FS_DEBUG
  47
  48 /*
  49  * Debug code
  50  */
  51 #ifdef EXT4FS_DEBUG
  52 #define ext4_debug(f, a...)                                             \
  53         do {                                                            \
  54                 printk(KERN_DEBUG "EXT4-fs DEBUG (%s, %d): %s:",        \
  55                         __FILE__, __LINE__, __func__);                  \
  56                 printk(KERN_DEBUG f, ## a);                             \
  57         } while (0)
  58 #else
  59 #define ext4_debug(fmt, ...)    no_printk(fmt, ##__VA_ARGS__)
  60 #endif
  61
  62 /*
  63  * Turn on EXT_DEBUG to get lots of info about extents operations.
  64  */
  65 #define EXT_DEBUG__
  66 #ifdef EXT_DEBUG
  67 #define ext_debug(fmt, ...)     printk(fmt, ##__VA_ARGS__)
  68 #else
  69 #define ext_debug(fmt, ...)     no_printk(fmt, ##__VA_ARGS__)
  70 #endif
  71
  72 #define EXT4_ERROR_INODE(inode, fmt, a...) \
  73         ext4_error_inode((inode), __func__, __LINE__, 0, (fmt), ## a)
  74
  75 #define EXT4_ERROR_INODE_BLOCK(inode, block, fmt, a...)                 \
  76         ext4_error_inode((inode), __func__, __LINE__, (block), (fmt), ## a)
  77
  78 #define EXT4_ERROR_FILE(file, block, fmt, a...)                         \
  79         ext4_error_file((file), __func__, __LINE__, (block), (fmt), ## a)
  80
  81 /* data type for block offset of block group */
  82 typedef int ext4_grpblk_t;
  83
  84 /* data type for filesystem-wide blocks number */
  85 typedef unsigned long long ext4_fsblk_t;
  86
  87 /* data type for file logical block number */
  88 typedef __u32 ext4_lblk_t;
  89
  90 /* data type for block group number */
  91 typedef unsigned int ext4_group_t;
  92
  93 /*
  94  * Flags used in mballoc's allocation_context flags field.
  95  *
  96  * Also used to show what's going on for debugging purposes when the
  97  * flag field is exported via the traceport interface
  98  */
  99
 100 /* prefer goal again. length */
 101 #define EXT4_MB_HINT_MERGE              0x0001
 102 /* blocks already reserved */
 103 #define EXT4_MB_HINT_RESERVED           0x0002
 104 /* metadata is being allocated */
 105 #define EXT4_MB_HINT_METADATA           0x0004
 106 /* first blocks in the file */
 107 #define EXT4_MB_HINT_FIRST              0x0008
 108 /* search for the best chunk */
 109 #define EXT4_MB_HINT_BEST               0x0010
 110 /* data is being allocated */
 111 #define EXT4_MB_HINT_DATA               0x0020
 112 /* don't preallocate (for tails) */
 113 #define EXT4_MB_HINT_NOPREALLOC         0x0040
 114 /* allocate for locality group */
 115 #define EXT4_MB_HINT_GROUP_ALLOC        0x0080
 116 /* allocate goal blocks or none */
 117 #define EXT4_MB_HINT_GOAL_ONLY          0x0100
 118 /* goal is meaningful */
 119 #define EXT4_MB_HINT_TRY_GOAL           0x0200
 120 /* blocks already pre-reserved by delayed allocation */
 121 #define EXT4_MB_DELALLOC_RESERVED       0x0400
 122 /* We are doing stream allocation */
 123 #define EXT4_MB_STREAM_ALLOC            0x0800
 124 /* Use reserved root blocks if needed */
 125 #define EXT4_MB_USE_ROOT_BLOCKS         0x1000
 126 /* Use blocks from reserved pool */
 127 #define EXT4_MB_USE_RESERVED            0x2000
 128
 129 struct ext4_allocation_request {
 130         /* target inode for block we're allocating */
 131         struct inode *inode;
 132         /* how many blocks we want to allocate */
 133         unsigned int len;
 134         /* logical block in target inode */
 135         ext4_lblk_t logical;
 136         /* the closest logical allocated block to the left */
 137         ext4_lblk_t lleft;
 138         /* the closest logical allocated block to the right */
 139         ext4_lblk_t lright;
 140         /* phys. target (a hint) */
 141         ext4_fsblk_t goal;
 142         /* phys. block for the closest logical allocated block to the left */
 143         ext4_fsblk_t pleft;
 144         /* phys. block for the closest logical allocated block to the right */
 145         ext4_fsblk_t pright;
 146         /* flags. see above EXT4_MB_HINT_* */
 147         unsigned int flags;
 148 };
 149
 150 /*
 151  * Logical to physical block mapping, used by ext4_map_blocks()
 152  *
 153  * This structure is used to pass requests into ext4_map_blocks() as
 154  * well as to store the information returned by ext4_map_blocks().  It
 155  * takes less room on the stack than a struct buffer_head.
 156  */
 157 #define EXT4_MAP_NEW            (1 << BH_New)
 158 #define EXT4_MAP_MAPPED         (1 << BH_Mapped)
 159 #define EXT4_MAP_UNWRITTEN      (1 << BH_Unwritten)
 160 #define EXT4_MAP_BOUNDARY       (1 << BH_Boundary)
 161 #define EXT4_MAP_FLAGS          (EXT4_MAP_NEW | EXT4_MAP_MAPPED |\
 162                                  EXT4_MAP_UNWRITTEN | EXT4_MAP_BOUNDARY)
 163
 164 struct ext4_map_blocks {
 165         ext4_fsblk_t m_pblk;
 166         ext4_lblk_t m_lblk;
 167         unsigned int m_len;
 168         unsigned int m_flags;
 169 };
 170
 171 /*
 172  * Flags for ext4_io_end->flags
 173  */
 174 #define EXT4_IO_END_UNWRITTEN   0x0001
 175
 176 /*
 177  * For converting unwritten extents on a work queue. 'handle' is used for
 178  * buffered writeback.
 179  */
 180 typedef struct ext4_io_end {
 181         struct list_head        list;           /* per-file finished IO list */
 182         handle_t                *handle;        /* handle reserved for extent
 183                                                  * conversion */
 184         struct inode            *inode;         /* file being written to */
 185         struct bio              *bio;           /* Linked list of completed
 186                                                  * bios covering the extent */
 187         unsigned int            flag;           /* unwritten or not */
 188         loff_t                  offset;         /* offset in the file */
 189         ssize_t                 size;           /* size of the extent */
 190         atomic_t                count;          /* reference counter */
 191 } ext4_io_end_t;
 192
 193 struct ext4_io_submit {
 194         int                     io_op;
 195         struct bio              *io_bio;
 196         ext4_io_end_t           *io_end;
 197         sector_t                io_next_block;
 198 };
 199
 200 /*
 201  * Special inodes numbers
 202  */
 203 #define EXT4_BAD_INO             1      /* Bad blocks inode */
 204 #define EXT4_ROOT_INO            2      /* Root inode */
 205 #define EXT4_USR_QUOTA_INO       3      /* User quota inode */
 206 #define EXT4_GRP_QUOTA_INO       4      /* Group quota inode */
 207 #define EXT4_BOOT_LOADER_INO     5      /* Boot loader inode */
 208 #define EXT4_UNDEL_DIR_INO       6      /* Undelete directory inode */
 209 #define EXT4_RESIZE_INO          7      /* Reserved group descriptors inode */
 210 #define EXT4_JOURNAL_INO         8      /* Journal inode */
 211
 212 /* First non-reserved inode for old ext4 filesystems */
 213 #define EXT4_GOOD_OLD_FIRST_INO 11
 214
 215 /*
 216  * Maximal count of links to a file
 217  */
 218 #define EXT4_LINK_MAX           65000
 219
 220 /*
 221  * Macro-instructions used to manage several block sizes
 222  */
 223 #define EXT4_MIN_BLOCK_SIZE             1024
 224 #define EXT4_MAX_BLOCK_SIZE             65536
 225 #define EXT4_MIN_BLOCK_LOG_SIZE         10
 226 #define EXT4_MAX_BLOCK_LOG_SIZE         16
 227 #ifdef __KERNEL__
 228 # define EXT4_BLOCK_SIZE(s)             ((s)->s_blocksize)
 229 #else
 230 # define EXT4_BLOCK_SIZE(s)             (EXT4_MIN_BLOCK_SIZE << (s)->s_log_block_size)
 231 #endif
 232 #define EXT4_ADDR_PER_BLOCK(s)          (EXT4_BLOCK_SIZE(s) / sizeof(__u32))
 233 #define EXT4_CLUSTER_SIZE(s)            (EXT4_BLOCK_SIZE(s) << \
 234                                          EXT4_SB(s)->s_cluster_bits)
 235 #ifdef __KERNEL__
 236 # define EXT4_BLOCK_SIZE_BITS(s)        ((s)->s_blocksize_bits)
 237 # define EXT4_CLUSTER_BITS(s)           (EXT4_SB(s)->s_cluster_bits)
 238 #else
 239 # define EXT4_BLOCK_SIZE_BITS(s)        ((s)->s_log_block_size + 10)
 240 #endif
 241 #ifdef __KERNEL__
 242 #define EXT4_ADDR_PER_BLOCK_BITS(s)     (EXT4_SB(s)->s_addr_per_block_bits)
 243 #define EXT4_INODE_SIZE(s)              (EXT4_SB(s)->s_inode_size)
 244 #define EXT4_FIRST_INO(s)               (EXT4_SB(s)->s_first_ino)
 245 #else
 246 #define EXT4_INODE_SIZE(s)      (((s)->s_rev_level == EXT4_GOOD_OLD_REV) ? \
 247                                  EXT4_GOOD_OLD_INODE_SIZE : \
 248                                  (s)->s_inode_size)
 249 #define EXT4_FIRST_INO(s)       (((s)->s_rev_level == EXT4_GOOD_OLD_REV) ? \
 250                                  EXT4_GOOD_OLD_FIRST_INO : \
 251                                  (s)->s_first_ino)
 252 #endif
 253 #define EXT4_BLOCK_ALIGN(size, blkbits)         ALIGN((size), (1 << (blkbits)))
 254
 255 /* Translate a block number to a cluster number */
 256 #define EXT4_B2C(sbi, blk)      ((blk) >> (sbi)->s_cluster_bits)
 257 /* Translate a cluster number to a block number */
 258 #define EXT4_C2B(sbi, cluster)  ((cluster) << (sbi)->s_cluster_bits)
 259 /* Translate # of blks to # of clusters */
 260 #define EXT4_NUM_B2C(sbi, blks) (((blks) + (sbi)->s_cluster_ratio - 1) >> \
 261                                  (sbi)->s_cluster_bits)
 262 /* Mask out the low bits to get the starting block of the cluster */
 263 #define EXT4_PBLK_CMASK(s, pblk) ((pblk) &                              \
 264                                   ~((ext4_fsblk_t) (s)->s_cluster_ratio - 1))
 265 #define EXT4_LBLK_CMASK(s, lblk) ((lblk) &                              \
 266                                   ~((ext4_lblk_t) (s)->s_cluster_ratio - 1))
 267 /* Get the cluster offset */
 268 #define EXT4_PBLK_COFF(s, pblk) ((pblk) &                               \
 269                                  ((ext4_fsblk_t) (s)->s_cluster_ratio - 1))
 270 #define EXT4_LBLK_COFF(s, lblk) ((lblk) &                               \
 271                                  ((ext4_lblk_t) (s)->s_cluster_ratio - 1))
 272
 273 /*
 274  * Structure of a blocks group descriptor
 275  */
 276 struct ext4_group_desc
 277 {
 278         __le32  bg_block_bitmap_lo;     /* Blocks bitmap block */
 279         __le32  bg_inode_bitmap_lo;     /* Inodes bitmap block */
 280         __le32  bg_inode_table_lo;      /* Inodes table block */
 281         __le16  bg_free_blocks_count_lo;/* Free blocks count */
 282         __le16  bg_free_inodes_count_lo;/* Free inodes count */
 283         __le16  bg_used_dirs_count_lo;  /* Directories count */
 284         __le16  bg_flags;               /* EXT4_BG_flags (INODE_UNINIT, etc) */
 285         __le32  bg_exclude_bitmap_lo;   /* Exclude bitmap for snapshots */
 286         __le16  bg_block_bitmap_csum_lo;/* crc32c(s_uuid+grp_num+bbitmap) LE */
 287         __le16  bg_inode_bitmap_csum_lo;/* crc32c(s_uuid+grp_num+ibitmap) LE */
 288         __le16  bg_itable_unused_lo;    /* Unused inodes count */
 289         __le16  bg_checksum;            /* crc16(sb_uuid+group+desc) */
 290         __le32  bg_block_bitmap_hi;     /* Blocks bitmap block MSB */
 291         __le32  bg_inode_bitmap_hi;     /* Inodes bitmap block MSB */
 292         __le32  bg_inode_table_hi;      /* Inodes table block MSB */
 293         __le16  bg_free_blocks_count_hi;/* Free blocks count MSB */
 294         __le16  bg_free_inodes_count_hi;/* Free inodes count MSB */
 295         __le16  bg_used_dirs_count_hi;  /* Directories count MSB */
 296         __le16  bg_itable_unused_hi;    /* Unused inodes count MSB */
 297         __le32  bg_exclude_bitmap_hi;   /* Exclude bitmap block MSB */
 298         __le16  bg_block_bitmap_csum_hi;/* crc32c(s_uuid+grp_num+bbitmap) BE */
 299         __le16  bg_inode_bitmap_csum_hi;/* crc32c(s_uuid+grp_num+ibitmap) BE */
 300         __u32   bg_reserved;
 301 };
 302
 303 #define EXT4_BG_INODE_BITMAP_CSUM_HI_END        \
 304         (offsetof(struct ext4_group_desc, bg_inode_bitmap_csum_hi) + \
 305          sizeof(__le16))
 306 #define EXT4_BG_BLOCK_BITMAP_CSUM_HI_END        \
 307         (offsetof(struct ext4_group_desc, bg_block_bitmap_csum_hi) + \
 308          sizeof(__le16))
 309
 310 /*
 311  * Structure of a flex block group info
 312  */
 313
 314 struct flex_groups {
 315         atomic64_t      free_clusters;
 316         atomic_t        free_inodes;
 317         atomic_t        used_dirs;
 318 };
 319
 320 #define EXT4_BG_INODE_UNINIT    0x0001 /* Inode table/bitmap not in use */
 321 #define EXT4_BG_BLOCK_UNINIT    0x0002 /* Block bitmap not in use */
 322 #define EXT4_BG_INODE_ZEROED    0x0004 /* On-disk itable initialized to zero */
 323
 324 /*
 325  * Macro-instructions used to manage group descriptors
 326  */
 327 #define EXT4_MIN_DESC_SIZE              32
 328 #define EXT4_MIN_DESC_SIZE_64BIT        64
 329 #define EXT4_MAX_DESC_SIZE              EXT4_MIN_BLOCK_SIZE
 330 #define EXT4_DESC_SIZE(s)               (EXT4_SB(s)->s_desc_size)
 331 #ifdef __KERNEL__
 332 # define EXT4_BLOCKS_PER_GROUP(s)       (EXT4_SB(s)->s_blocks_per_group)
 333 # define EXT4_CLUSTERS_PER_GROUP(s)     (EXT4_SB(s)->s_clusters_per_group)
 334 # define EXT4_DESC_PER_BLOCK(s)         (EXT4_SB(s)->s_desc_per_block)
 335 # define EXT4_INODES_PER_GROUP(s)       (EXT4_SB(s)->s_inodes_per_group)
 336 # define EXT4_DESC_PER_BLOCK_BITS(s)    (EXT4_SB(s)->s_desc_per_block_bits)
 337 #else
 338 # define EXT4_BLOCKS_PER_GROUP(s)       ((s)->s_blocks_per_group)
 339 # define EXT4_DESC_PER_BLOCK(s)         (EXT4_BLOCK_SIZE(s) / EXT4_DESC_SIZE(s))
 340 # define EXT4_INODES_PER_GROUP(s)       ((s)->s_inodes_per_group)
 341 #endif
 342
 343 /*
 344  * Constants relative to the data blocks
 345  */
 346 #define EXT4_NDIR_BLOCKS                12
 347 #define EXT4_IND_BLOCK                  EXT4_NDIR_BLOCKS
 348 #define EXT4_DIND_BLOCK                 (EXT4_IND_BLOCK + 1)
 349 #define EXT4_TIND_BLOCK                 (EXT4_DIND_BLOCK + 1)
 350 #define EXT4_N_BLOCKS                   (EXT4_TIND_BLOCK + 1)
 351
 352 /*
 353  * Inode flags
 354  */
 355 #define EXT4_SECRM_FL                   0x00000001 /* Secure deletion */
 356 #define EXT4_UNRM_FL                    0x00000002 /* Undelete */
 357 #define EXT4_COMPR_FL                   0x00000004 /* Compress file */
 358 #define EXT4_SYNC_FL                    0x00000008 /* Synchronous updates */
 359 #define EXT4_IMMUTABLE_FL               0x00000010 /* Immutable file */
 360 #define EXT4_APPEND_FL                  0x00000020 /* writes to file may only append */
 361 #define EXT4_NODUMP_FL                  0x00000040 /* do not dump file */
 362 #define EXT4_NOATIME_FL                 0x00000080 /* do not update atime */
 363 /* Reserved for compression usage... */
 364 #define EXT4_DIRTY_FL                   0x00000100
 365 #define EXT4_COMPRBLK_FL                0x00000200 /* One or more compressed clusters */
 366 #define EXT4_NOCOMPR_FL                 0x00000400 /* Don't compress */
 367 #define EXT4_ECOMPR_FL                  0x00000800 /* Compression error */
 368 /* End compression flags --- maybe not all used */
 369 #define EXT4_INDEX_FL                   0x00001000 /* hash-indexed directory */
 370 #define EXT4_IMAGIC_FL                  0x00002000 /* AFS directory */
 371 #define EXT4_JOURNAL_DATA_FL            0x00004000 /* file data should be journaled */
 372 #define EXT4_NOTAIL_FL                  0x00008000 /* file tail should not be merged */
 373 #define EXT4_DIRSYNC_FL                 0x00010000 /* dirsync behaviour (directories only) */
 374 #define EXT4_TOPDIR_FL                  0x00020000 /* Top of directory hierarchies*/
 375 #define EXT4_HUGE_FILE_FL               0x00040000 /* Set to each huge file */
 376 #define EXT4_EXTENTS_FL                 0x00080000 /* Inode uses extents */
 377 #define EXT4_EA_INODE_FL                0x00200000 /* Inode used for large EA */
 378 #define EXT4_EOFBLOCKS_FL               0x00400000 /* Blocks allocated beyond EOF */
 379 #define EXT4_INLINE_DATA_FL             0x10000000 /* Inode has inline data. */
 380 #define EXT4_RESERVED_FL                0x80000000 /* reserved for ext4 lib */
 381
 382 #define EXT4_FL_USER_VISIBLE            0x004BDFFF /* User visible flags */
 383 #define EXT4_FL_USER_MODIFIABLE         0x004380FF /* User modifiable flags */
 384
 385 /* Flags that should be inherited by new inodes from their parent. */
 386 #define EXT4_FL_INHERITED (EXT4_SECRM_FL | EXT4_UNRM_FL | EXT4_COMPR_FL |\
 387                            EXT4_SYNC_FL | EXT4_NODUMP_FL | EXT4_NOATIME_FL |\
 388                            EXT4_NOCOMPR_FL | EXT4_JOURNAL_DATA_FL |\
 389                            EXT4_NOTAIL_FL | EXT4_DIRSYNC_FL)
 390
 391 /* Flags that are appropriate for regular files (all but dir-specific ones). */
 392 #define EXT4_REG_FLMASK (~(EXT4_DIRSYNC_FL | EXT4_TOPDIR_FL))
 393
 394 /* Flags that are appropriate for non-directories/regular files. */
 395 #define EXT4_OTHER_FLMASK (EXT4_NODUMP_FL | EXT4_NOATIME_FL)
 396
 397 /* Mask out flags that are inappropriate for the given type of inode. */
 398 static inline __u32 ext4_mask_flags(umode_t mode, __u32 flags)
 399 {
 400         if (S_ISDIR(mode))
 401                 return flags;
 402         else if (S_ISREG(mode))
 403                 return flags & EXT4_REG_FLMASK;
 404         else
 405                 return flags & EXT4_OTHER_FLMASK;
 406 }
 407
 408 /*
 409  * Inode flags used for atomic set/get
 410  */
 411 enum {
 412         EXT4_INODE_SECRM        = 0,    /* Secure deletion */
 413         EXT4_INODE_UNRM         = 1,    /* Undelete */
 414         EXT4_INODE_COMPR        = 2,    /* Compress file */
 415         EXT4_INODE_SYNC         = 3,    /* Synchronous updates */
 416         EXT4_INODE_IMMUTABLE    = 4,    /* Immutable file */
 417         EXT4_INODE_APPEND       = 5,    /* writes to file may only append */
 418         EXT4_INODE_NODUMP       = 6,    /* do not dump file */
 419         EXT4_INODE_NOATIME      = 7,    /* do not update atime */
 420 /* Reserved for compression usage... */
 421         EXT4_INODE_DIRTY        = 8,
 422         EXT4_INODE_COMPRBLK     = 9,    /* One or more compressed clusters */
 423         EXT4_INODE_NOCOMPR      = 10,   /* Don't compress */
 424         EXT4_INODE_ECOMPR       = 11,   /* Compression error */
 425 /* End compression flags --- maybe not all used */
 426         EXT4_INODE_INDEX        = 12,   /* hash-indexed directory */
 427         EXT4_INODE_IMAGIC       = 13,   /* AFS directory */
 428         EXT4_INODE_JOURNAL_DATA = 14,   /* file data should be journaled */
 429         EXT4_INODE_NOTAIL       = 15,   /* file tail should not be merged */
 430         EXT4_INODE_DIRSYNC      = 16,   /* dirsync behaviour (directories only) */
 431         EXT4_INODE_TOPDIR       = 17,   /* Top of directory hierarchies*/
 432         EXT4_INODE_HUGE_FILE    = 18,   /* Set to each huge file */
 433         EXT4_INODE_EXTENTS      = 19,   /* Inode uses extents */
 434         EXT4_INODE_EA_INODE     = 21,   /* Inode used for large EA */
 435         EXT4_INODE_EOFBLOCKS    = 22,   /* Blocks allocated beyond EOF */
 436         EXT4_INODE_INLINE_DATA  = 28,   /* Data in inode. */
 437         EXT4_INODE_RESERVED     = 31,   /* reserved for ext4 lib */
 438 };
 439
 440 /*
 441  * Since it's pretty easy to mix up bit numbers and hex values, we use a
 442  * build-time check to make sure that EXT4_XXX_FL is consistent with respect to
 443  * EXT4_INODE_XXX. If all is well, the macros will be dropped, so, it won't cost
 444  * any extra space in the compiled kernel image, otherwise, the build will fail.
 445  * It's important that these values are the same, since we are using
 446  * EXT4_INODE_XXX to test for flag values, but EXT4_XXX_FL must be consistent
 447  * with the values of FS_XXX_FL defined in include/linux/fs.h and the on-disk
 448  * values found in ext2, ext3 and ext4 filesystems, and of course the values
 449  * defined in e2fsprogs.
 450  *
 451  * It's not paranoia if the Murphy's Law really *is* out to get you.  :-)
 452  */
 453 #define TEST_FLAG_VALUE(FLAG) (EXT4_##FLAG##_FL == (1 << EXT4_INODE_##FLAG))
 454 #define CHECK_FLAG_VALUE(FLAG) BUILD_BUG_ON(!TEST_FLAG_VALUE(FLAG))
 455
 456 static inline void ext4_check_flag_values(void)
 457 {
 458         CHECK_FLAG_VALUE(SECRM);
 459         CHECK_FLAG_VALUE(UNRM);
 460         CHECK_FLAG_VALUE(COMPR);
 461         CHECK_FLAG_VALUE(SYNC);
 462         CHECK_FLAG_VALUE(IMMUTABLE);
 463         CHECK_FLAG_VALUE(APPEND);
 464         CHECK_FLAG_VALUE(NODUMP);
 465         CHECK_FLAG_VALUE(NOATIME);
 466         CHECK_FLAG_VALUE(DIRTY);
 467         CHECK_FLAG_VALUE(COMPRBLK);
 468         CHECK_FLAG_VALUE(NOCOMPR);
 469         CHECK_FLAG_VALUE(ECOMPR);
 470         CHECK_FLAG_VALUE(INDEX);
 471         CHECK_FLAG_VALUE(IMAGIC);
 472         CHECK_FLAG_VALUE(JOURNAL_DATA);
 473         CHECK_FLAG_VALUE(NOTAIL);
 474         CHECK_FLAG_VALUE(DIRSYNC);
 475         CHECK_FLAG_VALUE(TOPDIR);
 476         CHECK_FLAG_VALUE(HUGE_FILE);
 477         CHECK_FLAG_VALUE(EXTENTS);
 478         CHECK_FLAG_VALUE(EA_INODE);
 479         CHECK_FLAG_VALUE(EOFBLOCKS);
 480         CHECK_FLAG_VALUE(INLINE_DATA);
 481         CHECK_FLAG_VALUE(RESERVED);
 482 }
 483
 484 /* Used to pass group descriptor data when online resize is done */
 485 struct ext4_new_group_input {
 486         __u32 group;            /* Group number for this data */
 487         __u64 block_bitmap;     /* Absolute block number of block bitmap */
 488         __u64 inode_bitmap;     /* Absolute block number of inode bitmap */
 489         __u64 inode_table;      /* Absolute block number of inode table start */
 490         __u32 blocks_count;     /* Total number of blocks in this group */
 491         __u16 reserved_blocks;  /* Number of reserved blocks in this group */
 492         __u16 unused;
 493 };
 494
 495 #if defined(__KERNEL__) && defined(CONFIG_COMPAT)
 496 struct compat_ext4_new_group_input {
 497         u32 group;
 498         compat_u64 block_bitmap;
 499         compat_u64 inode_bitmap;
 500         compat_u64 inode_table;
 501         u32 blocks_count;
 502         u16 reserved_blocks;
 503         u16 unused;
 504 };
 505 #endif
 506
 507 /* The struct ext4_new_group_input in kernel space, with free_blocks_count */
 508 struct ext4_new_group_data {
 509         __u32 group;
 510         __u64 block_bitmap;
 511         __u64 inode_bitmap;
 512         __u64 inode_table;
 513         __u32 blocks_count;
 514         __u16 reserved_blocks;
 515         __u16 unused;
 516         __u32 free_blocks_count;
 517 };
 518
 519 /* Indexes used to index group tables in ext4_new_group_data */
 520 enum {
 521         BLOCK_BITMAP = 0,       /* block bitmap */
 522         INODE_BITMAP,           /* inode bitmap */
 523         INODE_TABLE,            /* inode tables */
 524         GROUP_TABLE_COUNT,
 525 };
 526
 527 /*
 528  * Flags used by ext4_map_blocks()
 529  */
 530         /* Allocate any needed blocks and/or convert an unwritten
 531            extent to be an initialized ext4 */
 532 #define EXT4_GET_BLOCKS_CREATE                  0x0001
 533         /* Request the creation of an unwritten extent */
 534 #define EXT4_GET_BLOCKS_UNWRIT_EXT              0x0002
 535 #define EXT4_GET_BLOCKS_CREATE_UNWRIT_EXT       (EXT4_GET_BLOCKS_UNWRIT_EXT|\
 536                                                  EXT4_GET_BLOCKS_CREATE)
 537         /* Caller is from the delayed allocation writeout path
 538          * finally doing the actual allocation of delayed blocks */
 539 #define EXT4_GET_BLOCKS_DELALLOC_RESERVE        0x0004
 540         /* caller is from the direct IO path, request to creation of an
 541         unwritten extents if not allocated, split the unwritten
 542         extent if blocks has been preallocated already*/
 543 #define EXT4_GET_BLOCKS_PRE_IO                  0x0008
 544 #define EXT4_GET_BLOCKS_CONVERT                 0x0010
 545 #define EXT4_GET_BLOCKS_IO_CREATE_EXT           (EXT4_GET_BLOCKS_PRE_IO|\
 546                                          EXT4_GET_BLOCKS_CREATE_UNWRIT_EXT)
 547         /* Convert extent to initialized after IO complete */
 548 #define EXT4_GET_BLOCKS_IO_CONVERT_EXT          (EXT4_GET_BLOCKS_CONVERT|\
 549                                          EXT4_GET_BLOCKS_CREATE_UNWRIT_EXT)
 550         /* Eventual metadata allocation (due to growing extent tree)
 551          * should not fail, so try to use reserved blocks for that.*/
 552 #define EXT4_GET_BLOCKS_METADATA_NOFAIL         0x0020
 553         /* Don't normalize allocation size (used for fallocate) */
 554 #define EXT4_GET_BLOCKS_NO_NORMALIZE            0x0040
 555         /* Request will not result in inode size update (user for fallocate) */
 556 #define EXT4_GET_BLOCKS_KEEP_SIZE               0x0080
 557         /* Do not take i_data_sem locking in ext4_map_blocks */
 558 #define EXT4_GET_BLOCKS_NO_LOCK                 0x0100
 559         /* Convert written extents to unwritten */
 560 #define EXT4_GET_BLOCKS_CONVERT_UNWRITTEN       0x0200
 561
 562 /*
 563  * The bit position of these flags must not overlap with any of the
 564  * EXT4_GET_BLOCKS_*.  They are used by ext4_find_extent(),
 565  * read_extent_tree_block(), ext4_split_extent_at(),
 566  * ext4_ext_insert_extent(), and ext4_ext_create_new_leaf().
 567  * EXT4_EX_NOCACHE is used to indicate that the we shouldn't be
 568  * caching the extents when reading from the extent tree while a
 569  * truncate or punch hole operation is in progress.
 570  */
 571 #define EXT4_EX_NOCACHE                         0x40000000
 572 #define EXT4_EX_FORCE_CACHE                     0x20000000
 573
 574 /*
 575  * Flags used by ext4_free_blocks
 576  */
 577 #define EXT4_FREE_BLOCKS_METADATA       0x0001
 578 #define EXT4_FREE_BLOCKS_FORGET         0x0002
 579 #define EXT4_FREE_BLOCKS_VALIDATED      0x0004
 580 #define EXT4_FREE_BLOCKS_NO_QUOT_UPDATE 0x0008
 581 #define EXT4_FREE_BLOCKS_NOFREE_FIRST_CLUSTER   0x0010
 582 #define EXT4_FREE_BLOCKS_NOFREE_LAST_CLUSTER    0x0020
 583
 584 /*
 585  * ioctl commands
 586  */
 587 #define EXT4_IOC_GETFLAGS               FS_IOC_GETFLAGS
 588 #define EXT4_IOC_SETFLAGS               FS_IOC_SETFLAGS
 589 #define EXT4_IOC_GETVERSION             _IOR('f', 3, long)
 590 #define EXT4_IOC_SETVERSION             _IOW('f', 4, long)
 591 #define EXT4_IOC_GETVERSION_OLD         FS_IOC_GETVERSION
 592 #define EXT4_IOC_SETVERSION_OLD         FS_IOC_SETVERSION
 593 #define EXT4_IOC_GETRSVSZ               _IOR('f', 5, long)
 594 #define EXT4_IOC_SETRSVSZ               _IOW('f', 6, long)
 595 #define EXT4_IOC_GROUP_EXTEND           _IOW('f', 7, unsigned long)
 596 #define EXT4_IOC_GROUP_ADD              _IOW('f', 8, struct ext4_new_group_input)
 597 #define EXT4_IOC_MIGRATE                _IO('f', 9)
 598  /* note ioctl 10 reserved for an early version of the FIEMAP ioctl */
 599  /* note ioctl 11 reserved for filesystem-independent FIEMAP ioctl */
 600 #define EXT4_IOC_ALLOC_DA_BLKS          _IO('f', 12)
 601 #define EXT4_IOC_MOVE_EXT               _IOWR('f', 15, struct move_extent)
 602 #define EXT4_IOC_RESIZE_FS              _IOW('f', 16, __u64)
 603 #define EXT4_IOC_SWAP_BOOT              _IO('f', 17)
 604 #define EXT4_IOC_PRECACHE_EXTENTS       _IO('f', 18)
 605
 606 #if defined(__KERNEL__) && defined(CONFIG_COMPAT)
 607 /*
 608  * ioctl commands in 32 bit emulation
 609  */
 610 #define EXT4_IOC32_GETFLAGS             FS_IOC32_GETFLAGS
 611 #define EXT4_IOC32_SETFLAGS             FS_IOC32_SETFLAGS
 612 #define EXT4_IOC32_GETVERSION           _IOR('f', 3, int)
 613 #define EXT4_IOC32_SETVERSION           _IOW('f', 4, int)
 614 #define EXT4_IOC32_GETRSVSZ             _IOR('f', 5, int)
 615 #define EXT4_IOC32_SETRSVSZ             _IOW('f', 6, int)
 616 #define EXT4_IOC32_GROUP_EXTEND         _IOW('f', 7, unsigned int)
 617 #define EXT4_IOC32_GROUP_ADD            _IOW('f', 8, struct compat_ext4_new_group_input)
 618 #define EXT4_IOC32_GETVERSION_OLD       FS_IOC32_GETVERSION
 619 #define EXT4_IOC32_SETVERSION_OLD       FS_IOC32_SETVERSION
 620 #endif
 621
 622 /* Max physical block we can address w/o extents */
 623 #define EXT4_MAX_BLOCK_FILE_PHYS        0xFFFFFFFF
 624
 625 /*
 626  * Structure of an inode on the disk
 627  */
 628 struct ext4_inode {
 629         __le16  i_mode;         /* File mode */
 630         __le16  i_uid;          /* Low 16 bits of Owner Uid */
 631         __le32  i_size_lo;      /* Size in bytes */
 632         __le32  i_atime;        /* Access time */
 633         __le32  i_ctime;        /* Inode Change time */
 634         __le32  i_mtime;        /* Modification time */
 635         __le32  i_dtime;        /* Deletion Time */
 636         __le16  i_gid;          /* Low 16 bits of Group Id */
 637         __le16  i_links_count;  /* Links count */
 638         __le32  i_blocks_lo;    /* Blocks count */
 639         __le32  i_flags;        /* File flags */
 640         union {
 641                 struct {
 642                         __le32  l_i_version;
 643                 } linux1;
 644                 struct {
 645                         __u32  h_i_translator;
 646                 } hurd1;
 647                 struct {
 648                         __u32  m_i_reserved1;
 649                 } masix1;
 650         } osd1;                         /* OS dependent 1 */
 651         __le32  i_block[EXT4_N_BLOCKS];/* Pointers to blocks */
 652         __le32  i_generation;   /* File version (for NFS) */
 653         __le32  i_file_acl_lo;  /* File ACL */
 654         __le32  i_size_high;
 655         __le32  i_obso_faddr;   /* Obsoleted fragment address */
 656         union {
 657                 struct {
 658                         __le16  l_i_blocks_high; /* were l_i_reserved1 */
 659                         __le16  l_i_file_acl_high;
 660                         __le16  l_i_uid_high;   /* these 2 fields */
 661                         __le16  l_i_gid_high;   /* were reserved2[0] */
 662                         __le16  l_i_checksum_lo;/* crc32c(uuid+inum+inode) LE */
 663                         __le16  l_i_reserved;
 664                 } linux2;
 665                 struct {
 666                         __le16  h_i_reserved1;  /* Obsoleted fragment number/size which are removed in ext4 */
 667                         __u16   h_i_mode_high;
 668                         __u16   h_i_uid_high;
 669                         __u16   h_i_gid_high;
 670                         __u32   h_i_author;
 671                 } hurd2;
 672                 struct {
 673                         __le16  h_i_reserved1;  /* Obsoleted fragment number/size which are removed in ext4 */
 674                         __le16  m_i_file_acl_high;
 675                         __u32   m_i_reserved2[2];
 676                 } masix2;
 677         } osd2;                         /* OS dependent 2 */
 678         __le16  i_extra_isize;
 679         __le16  i_checksum_hi;  /* crc32c(uuid+inum+inode) BE */
 680         __le32  i_ctime_extra;  /* extra Change time      (nsec << 2 | epoch) */
 681         __le32  i_mtime_extra;  /* extra Modification time(nsec << 2 | epoch) */
 682         __le32  i_atime_extra;  /* extra Access time      (nsec << 2 | epoch) */
 683         __le32  i_crtime;       /* File Creation time */
 684         __le32  i_crtime_extra; /* extra FileCreationtime (nsec << 2 | epoch) */
 685         __le32  i_version_hi;   /* high 32 bits for 64-bit version */
 686 };
 687
 688 struct move_extent {
 689         __u32 reserved;         /* should be zero */
 690         __u32 donor_fd;         /* donor file descriptor */
 691         __u64 orig_start;       /* logical start offset in block for orig */
 692         __u64 donor_start;      /* logical start offset in block for donor */
 693         __u64 len;              /* block length to be moved */
 694         __u64 moved_len;        /* moved block length */
 695 };
 696
 697 #define EXT4_EPOCH_BITS 2
 698 #define EXT4_EPOCH_MASK ((1 << EXT4_EPOCH_BITS) - 1)
 699 #define EXT4_NSEC_MASK  (~0UL << EXT4_EPOCH_BITS)
 700
 701 /*
 702  * Extended fields will fit into an inode if the filesystem was formatted
 703  * with large inodes (-I 256 or larger) and there are not currently any EAs
 704  * consuming all of the available space. For new inodes we always reserve
 705  * enough space for the kernel's known extended fields, but for inodes
 706  * created with an old kernel this might not have been the case. None of
 707  * the extended inode fields is critical for correct filesystem operation.
 708  * This macro checks if a certain field fits in the inode. Note that
 709  * inode-size = GOOD_OLD_INODE_SIZE + i_extra_isize
 710  */
 711 #define EXT4_FITS_IN_INODE(ext4_inode, einode, field)   \
 712         ((offsetof(typeof(*ext4_inode), field) +        \
 713           sizeof((ext4_inode)->field))                  \
 714         <= (EXT4_GOOD_OLD_INODE_SIZE +                  \
 715             (einode)->i_extra_isize))                   \
 716
 717 static inline __le32 ext4_encode_extra_time(struct timespec *time)
 718 {
 719        return cpu_to_le32((sizeof(time->tv_sec) > 4 ?
 720                            (time->tv_sec >> 32) & EXT4_EPOCH_MASK : 0) |
 721                           ((time->tv_nsec << EXT4_EPOCH_BITS) & EXT4_NSEC_MASK));
 722 }
 723
 724 static inline void ext4_decode_extra_time(struct timespec *time, __le32 extra)
 725 {
 726        if (sizeof(time->tv_sec) > 4)
 727                time->tv_sec |= (__u64)(le32_to_cpu(extra) & EXT4_EPOCH_MASK)
 728                                << 32;
 729        time->tv_nsec = (le32_to_cpu(extra) & EXT4_NSEC_MASK) >> EXT4_EPOCH_BITS;
 730 }
 731
 732 #define EXT4_INODE_SET_XTIME(xtime, inode, raw_inode)                          \
 733 do {                                                                           \
 734         (raw_inode)->xtime = cpu_to_le32((inode)->xtime.tv_sec);               \
 735         if (EXT4_FITS_IN_INODE(raw_inode, EXT4_I(inode), xtime ## _extra))     \
 736                 (raw_inode)->xtime ## _extra =                                 \
 737                                 ext4_encode_extra_time(&(inode)->xtime);       \
 738 } while (0)
 739
 740 #define EXT4_EINODE_SET_XTIME(xtime, einode, raw_inode)                        \
 741 do {                                                                           \
 742         if (EXT4_FITS_IN_INODE(raw_inode, einode, xtime))                      \
 743                 (raw_inode)->xtime = cpu_to_le32((einode)->xtime.tv_sec);      \
 744         if (EXT4_FITS_IN_INODE(raw_inode, einode, xtime ## _extra))            \
 745                 (raw_inode)->xtime ## _extra =                                 \
 746                                 ext4_encode_extra_time(&(einode)->xtime);      \
 747 } while (0)
 748
 749 #define EXT4_INODE_GET_XTIME(xtime, inode, raw_inode)                          \
 750 do {                                                                           \
 751         (inode)->xtime.tv_sec = (signed)le32_to_cpu((raw_inode)->xtime);       \
 752         if (EXT4_FITS_IN_INODE(raw_inode, EXT4_I(inode), xtime ## _extra))     \
 753                 ext4_decode_extra_time(&(inode)->xtime,                        \
 754                                        raw_inode->xtime ## _extra);            \
 755         else                                                                   \
 756                 (inode)->xtime.tv_nsec = 0;                                    \
 757 } while (0)
 758
 759 #define EXT4_EINODE_GET_XTIME(xtime, einode, raw_inode)                        \
 760 do {                                                                           \
 761         if (EXT4_FITS_IN_INODE(raw_inode, einode, xtime))                      \
 762                 (einode)->xtime.tv_sec =                                       \
 763                         (signed)le32_to_cpu((raw_inode)->xtime);               \
 764         else                                                                   \
 765                 (einode)->xtime.tv_sec = 0;                                    \
 766         if (EXT4_FITS_IN_INODE(raw_inode, einode, xtime ## _extra))            \
 767                 ext4_decode_extra_time(&(einode)->xtime,                       \
 768                                        raw_inode->xtime ## _extra);            \
 769         else                                                                   \
 770                 (einode)->xtime.tv_nsec = 0;                                   \
 771 } while (0)
 772
 773 #define i_disk_version osd1.linux1.l_i_version
 774
 775 #if defined(__KERNEL__) || defined(__linux__)
 776 #define i_reserved1     osd1.linux1.l_i_reserved1
 777 #define i_file_acl_high osd2.linux2.l_i_file_acl_high
 778 #define i_blocks_high   osd2.linux2.l_i_blocks_high
 779 #define i_uid_low       i_uid
 780 #define i_gid_low       i_gid
 781 #define i_uid_high      osd2.linux2.l_i_uid_high
 782 #define i_gid_high      osd2.linux2.l_i_gid_high
 783 #define i_checksum_lo   osd2.linux2.l_i_checksum_lo
 784
 785 #elif defined(__GNU__)
 786
 787 #define i_translator    osd1.hurd1.h_i_translator
 788 #define i_uid_high      osd2.hurd2.h_i_uid_high
 789 #define i_gid_high      osd2.hurd2.h_i_gid_high
 790 #define i_author        osd2.hurd2.h_i_author
 791
 792 #elif defined(__masix__)
 793
 794 #define i_reserved1     osd1.masix1.m_i_reserved1
 795 #define i_file_acl_high osd2.masix2.m_i_file_acl_high
 796 #define i_reserved2     osd2.masix2.m_i_reserved2
 797
 798 #endif /* defined(__KERNEL__) || defined(__linux__) */
 799
 800 #include "extents_status.h"
 801
 802 /*
 803  * fourth extended file system inode data in memory
 804  */
 805 struct ext4_inode_info {
 806         __le32  i_data[15];     /* unconverted */
 807         __u32   i_dtime;
 808         ext4_fsblk_t    i_file_acl;
 809
 810         /*
 811          * i_block_group is the number of the block group which contains
 812          * this file's inode.  Constant across the lifetime of the inode,
 813          * it is ued for making block allocation decisions - we try to
 814          * place a file's data blocks near its inode block, and new inodes
 815          * near to their parent directory's inode.
 816          */
 817         ext4_group_t    i_block_group;
 818         ext4_lblk_t     i_dir_start_lookup;
 819 #if (BITS_PER_LONG < 64)
 820         unsigned long   i_state_flags;          /* Dynamic state flags */
 821 #endif
 822         unsigned long   i_flags;
 823
 824         /*
 825          * Extended attributes can be read independently of the main file
 826          * data. Taking i_mutex even when reading would cause contention
 827          * between readers of EAs and writers of regular file data, so
 828          * instead we synchronize on xattr_sem when reading or changing
 829          * EAs.
 830          */
 831         struct rw_semaphore xattr_sem;
 832
 833         struct list_head i_orphan;      /* unlinked but open inodes */
 834
 835         /*
 836          * i_disksize keeps track of what the inode size is ON DISK, not
 837          * in memory.  During truncate, i_size is set to the new size by
 838          * the VFS prior to calling ext4_truncate(), but the filesystem won't
 839          * set i_disksize to 0 until the truncate is actually under way.
 840          *
 841          * The intent is that i_disksize always represents the blocks which
 842          * are used by this file.  This allows recovery to restart truncate
 843          * on orphans if we crash during truncate.  We actually write i_disksize
 844          * into the on-disk inode when writing inodes out, instead of i_size.
 845          *
 846          * The only time when i_disksize and i_size may be different is when
 847          * a truncate is in progress.  The only things which change i_disksize
 848          * are ext4_get_block (growth) and ext4_truncate (shrinkth).
 849          */
 850         loff_t  i_disksize;
 851
 852         /*
 853          * i_data_sem is for serialising ext4_truncate() against
 854          * ext4_getblock().  In the 2.4 ext2 design, great chunks of inode's
 855          * data tree are chopped off during truncate. We can't do that in
 856          * ext4 because whenever we perform intermediate commits during
 857          * truncate, the inode and all the metadata blocks *must* be in a
 858          * consistent state which allows truncation of the orphans to restart
 859          * during recovery.  Hence we must fix the get_block-vs-truncate race
 860          * by other means, so we have i_data_sem.
 861          */
 862         struct rw_semaphore i_data_sem;
 863         struct inode vfs_inode;
 864         struct jbd2_inode *jinode;
 865
 866         spinlock_t i_raw_lock;  /* protects updates to the raw inode */
 867
 868         /*
 869          * File creation time. Its function is same as that of
 870          * struct timespec i_{a,c,m}time in the generic inode.
 871          */
 872         struct timespec i_crtime;
 873
 874         /* mballoc */
 875         struct list_head i_prealloc_list;
 876         spinlock_t i_prealloc_lock;
 877
 878         /* extents status tree */
 879         struct ext4_es_tree i_es_tree;
 880         rwlock_t i_es_lock;
 881         struct list_head i_es_list;
 882         unsigned int i_es_all_nr;       /* protected by i_es_lock */
 883         unsigned int i_es_shk_nr;       /* protected by i_es_lock */
 884         ext4_lblk_t i_es_shrink_lblk;   /* Offset where we start searching for
 885                                            extents to shrink. Protected by
 886                                            i_es_lock  */
 887
 888         /* ialloc */
 889         ext4_group_t    i_last_alloc_group;
 890
 891         /* allocation reservation info for delalloc */
 892         /* In case of bigalloc, these refer to clusters rather than blocks */
 893         unsigned int i_reserved_data_blocks;
 894         unsigned int i_reserved_meta_blocks;
 895         unsigned int i_allocated_meta_blocks;
 896         ext4_lblk_t i_da_metadata_calc_last_lblock;
 897         int i_da_metadata_calc_len;
 898
 899         /* on-disk additional length */
 900         __u16 i_extra_isize;
 901
 902         /* Indicate the inline data space. */
 903         u16 i_inline_off;
 904         u16 i_inline_size;
 905
 906 #ifdef CONFIG_QUOTA
 907         /* quota space reservation, managed internally by quota code */
 908         qsize_t i_reserved_quota;
 909 #endif
 910
 911         /* Lock protecting lists below */
 912         spinlock_t i_completed_io_lock;
 913         /*
 914          * Completed IOs that need unwritten extents handling and have
 915          * transaction reserved
 916          */
 917         struct list_head i_rsv_conversion_list;
 918         /*
 919          * Completed IOs that need unwritten extents handling and don't have
 920          * transaction reserved
 921          */
 922         atomic_t i_ioend_count; /* Number of outstanding io_end structs */
 923         atomic_t i_unwritten; /* Nr. of inflight conversions pending */
 924         struct work_struct i_rsv_conversion_work;
 925
 926         spinlock_t i_block_reservation_lock;
 927
 928         /*
 929          * Transactions that contain inode's metadata needed to complete
 930          * fsync and fdatasync, respectively.
 931          */
 932         tid_t i_sync_tid;
 933         tid_t i_datasync_tid;
 934
 935 #ifdef CONFIG_QUOTA
 936         struct dquot *i_dquot[MAXQUOTAS];
 937 #endif
 938
 939         /* Precomputed uuid+inum+igen checksum for seeding inode checksums */
 940         __u32 i_csum_seed;
 941 };
 942
 943 /*
 944  * File system states
 945  */
 946 #define EXT4_VALID_FS                   0x0001  /* Unmounted cleanly */
 947 #define EXT4_ERROR_FS                   0x0002  /* Errors detected */
 948 #define EXT4_ORPHAN_FS                  0x0004  /* Orphans being recovered */
 949
 950 /*
 951  * Misc. filesystem flags
 952  */
 953 #define EXT2_FLAGS_SIGNED_HASH          0x0001  /* Signed dirhash in use */
 954 #define EXT2_FLAGS_UNSIGNED_HASH        0x0002  /* Unsigned dirhash in use */
 955 #define EXT2_FLAGS_TEST_FILESYS         0x0004  /* to test development code */
 956
 957 /*
 958  * Mount flags set via mount options or defaults
 959  */
 960 #define EXT4_MOUNT_GRPID                0x00004 /* Create files with directory's group */
 961 #define EXT4_MOUNT_DEBUG                0x00008 /* Some debugging messages */
 962 #define EXT4_MOUNT_ERRORS_CONT          0x00010 /* Continue on errors */
 963 #define EXT4_MOUNT_ERRORS_RO            0x00020 /* Remount fs ro on errors */
 964 #define EXT4_MOUNT_ERRORS_PANIC         0x00040 /* Panic on errors */
 965 #define EXT4_MOUNT_ERRORS_MASK          0x00070
 966 #define EXT4_MOUNT_MINIX_DF             0x00080 /* Mimics the Minix statfs */
 967 #define EXT4_MOUNT_NOLOAD               0x00100 /* Don't use existing journal*/
 968 #define EXT4_MOUNT_DATA_FLAGS           0x00C00 /* Mode for data writes: */
 969 #define EXT4_MOUNT_JOURNAL_DATA         0x00400 /* Write data to journal */
 970 #define EXT4_MOUNT_ORDERED_DATA         0x00800 /* Flush data before commit */
 971 #define EXT4_MOUNT_WRITEBACK_DATA       0x00C00 /* No data ordering */
 972 #define EXT4_MOUNT_UPDATE_JOURNAL       0x01000 /* Update the journal format */
 973 #define EXT4_MOUNT_NO_UID32             0x02000  /* Disable 32-bit UIDs */
 974 #define EXT4_MOUNT_XATTR_USER           0x04000 /* Extended user attributes */
 975 #define EXT4_MOUNT_POSIX_ACL            0x08000 /* POSIX Access Control Lists */
 976 #define EXT4_MOUNT_NO_AUTO_DA_ALLOC     0x10000 /* No auto delalloc mapping */
 977 #define EXT4_MOUNT_BARRIER              0x20000 /* Use block barriers */
 978 #define EXT4_MOUNT_QUOTA                0x80000 /* Some quota option set */
 979 #define EXT4_MOUNT_USRQUOTA             0x100000 /* "old" user quota */
 980 #define EXT4_MOUNT_GRPQUOTA             0x200000 /* "old" group quota */
 981 #define EXT4_MOUNT_DIOREAD_NOLOCK       0x400000 /* Enable support for dio read nolocking */
 982 #define EXT4_MOUNT_JOURNAL_CHECKSUM     0x800000 /* Journal checksums */
 983 #define EXT4_MOUNT_JOURNAL_ASYNC_COMMIT 0x1000000 /* Journal Async Commit */
 984 #define EXT4_MOUNT_DELALLOC             0x8000000 /* Delalloc support */
 985 #define EXT4_MOUNT_DATA_ERR_ABORT       0x10000000 /* Abort on file data write */
 986 #define EXT4_MOUNT_BLOCK_VALIDITY       0x20000000 /* Block validity checking */
 987 #define EXT4_MOUNT_DISCARD              0x40000000 /* Issue DISCARD requests */
 988 #define EXT4_MOUNT_INIT_INODE_TABLE     0x80000000 /* Initialize uninitialized itables */
 989
 990 /*
 991  * Mount flags set either automatically (could not be set by mount option)
 992  * based on per file system feature or property or in special cases such as
 993  * distinguishing between explicit mount option definition and default.
 994  */
 995 #define EXT4_MOUNT2_EXPLICIT_DELALLOC   0x00000001 /* User explicitly
 996                                                       specified delalloc */
 997 #define EXT4_MOUNT2_STD_GROUP_SIZE      0x00000002 /* We have standard group
 998                                                       size of blocksize * 8
 999                                                       blocks */
1000 #define EXT4_MOUNT2_HURD_COMPAT         0x00000004 /* Support HURD-castrated
1001                                                       file systems */
1002
1003 #define clear_opt(sb, opt)              EXT4_SB(sb)->s_mount_opt &= \
1004                                                 ~EXT4_MOUNT_##opt
1005 #define set_opt(sb, opt)                EXT4_SB(sb)->s_mount_opt |= \
1006                                                 EXT4_MOUNT_##opt
1007 #define test_opt(sb, opt)               (EXT4_SB(sb)->s_mount_opt & \
1008                                          EXT4_MOUNT_##opt)
1009
1010 #define clear_opt2(sb, opt)             EXT4_SB(sb)->s_mount_opt2 &= \
1011                                                 ~EXT4_MOUNT2_##opt
1012 #define set_opt2(sb, opt)               EXT4_SB(sb)->s_mount_opt2 |= \
1013                                                 EXT4_MOUNT2_##opt
1014 #define test_opt2(sb, opt)              (EXT4_SB(sb)->s_mount_opt2 & \
1015                                          EXT4_MOUNT2_##opt)
1016
1017 #define ext4_test_and_set_bit           __test_and_set_bit_le
1018 #define ext4_set_bit                    __set_bit_le
1019 #define ext4_set_bit_atomic             ext2_set_bit_atomic
1020 #define ext4_test_and_clear_bit         __test_and_clear_bit_le
1021 #define ext4_clear_bit                  __clear_bit_le
1022 #define ext4_clear_bit_atomic           ext2_clear_bit_atomic
1023 #define ext4_test_bit                   test_bit_le
1024 #define ext4_find_next_zero_bit         find_next_zero_bit_le
1025 #define ext4_find_next_bit              find_next_bit_le
1026
1027 extern void ext4_set_bits(void *bm, int cur, int len);
1028
1029 /*
1030  * Maximal mount counts between two filesystem checks
1031  */
1032 #define EXT4_DFL_MAX_MNT_COUNT          20      /* Allow 20 mounts */
1033 #define EXT4_DFL_CHECKINTERVAL          0       /* Don't use interval check */
1034
1035 /*
1036  * Behaviour when detecting errors
1037  */
1038 #define EXT4_ERRORS_CONTINUE            1       /* Continue execution */
1039 #define EXT4_ERRORS_RO                  2       /* Remount fs read-only */
1040 #define EXT4_ERRORS_PANIC               3       /* Panic */
1041 #define EXT4_ERRORS_DEFAULT             EXT4_ERRORS_CONTINUE
1042
1043 /* Metadata checksum algorithm codes */
1044 #define EXT4_CRC32C_CHKSUM              1
1045
1046 /*
1047  * Structure of the super block
1048  */
1049 struct ext4_super_block {
1050 /*00*/  __le32  s_inodes_count;         /* Inodes count */
1051         __le32  s_blocks_count_lo;      /* Blocks count */
1052         __le32  s_r_blocks_count_lo;    /* Reserved blocks count */
1053         __le32  s_free_blocks_count_lo; /* Free blocks count */
1054 /*10*/  __le32  s_free_inodes_count;    /* Free inodes count */
1055         __le32  s_first_data_block;     /* First Data Block */
1056         __le32  s_log_block_size;       /* Block size */
1057         __le32  s_log_cluster_size;     /* Allocation cluster size */
1058 /*20*/  __le32  s_blocks_per_group;     /* # Blocks per group */
1059         __le32  s_clusters_per_group;   /* # Clusters per group */
1060         __le32  s_inodes_per_group;     /* # Inodes per group */
1061         __le32  s_mtime;                /* Mount time */
1062 /*30*/  __le32  s_wtime;                /* Write time */
1063         __le16  s_mnt_count;            /* Mount count */
1064         __le16  s_max_mnt_count;        /* Maximal mount count */
1065         __le16  s_magic;                /* Magic signature */
1066         __le16  s_state;                /* File system state */
1067         __le16  s_errors;               /* Behaviour when detecting errors */
1068         __le16  s_minor_rev_level;      /* minor revision level */
1069 /*40*/  __le32  s_lastcheck;            /* time of last check */
1070         __le32  s_checkinterval;        /* max. time between checks */
1071         __le32  s_creator_os;           /* OS */
1072         __le32  s_rev_level;            /* Revision level */
1073 /*50*/  __le16  s_def_resuid;           /* Default uid for reserved blocks */
1074         __le16  s_def_resgid;           /* Default gid for reserved blocks */
1075         /*
1076          * These fields are for EXT4_DYNAMIC_REV superblocks only.
1077          *
1078          * Note: the difference between the compatible feature set and
1079          * the incompatible feature set is that if there is a bit set
1080          * in the incompatible feature set that the kernel doesn't
1081          * know about, it should refuse to mount the filesystem.
1082          *
1083          * e2fsck's requirements are more strict; if it doesn't know
1084          * about a feature in either the compatible or incompatible
1085          * feature set, it must abort and not try to meddle with
1086          * things it doesn't understand...
1087          */
1088         __le32  s_first_ino;            /* First non-reserved inode */
1089         __le16  s_inode_size;           /* size of inode structure */
1090         __le16  s_block_group_nr;       /* block group # of this superblock */
1091         __le32  s_feature_compat;       /* compatible feature set */
1092 /*60*/  __le32  s_feature_incompat;     /* incompatible feature set */
1093         __le32  s_feature_ro_compat;    /* readonly-compatible feature set */
1094 /*68*/  __u8    s_uuid[16];             /* 128-bit uuid for volume */
1095 /*78*/  char    s_volume_name[16];      /* volume name */
1096 /*88*/  char    s_last_mounted[64];     /* directory where last mounted */
1097 /*C8*/  __le32  s_algorithm_usage_bitmap; /* For compression */
1098         /*
1099          * Performance hints.  Directory preallocation should only
1100          * happen if the EXT4_FEATURE_COMPAT_DIR_PREALLOC flag is on.
1101          */
1102         __u8    s_prealloc_blocks;      /* Nr of blocks to try to preallocate*/
1103         __u8    s_prealloc_dir_blocks;  /* Nr to preallocate for dirs */
1104         __le16  s_reserved_gdt_blocks;  /* Per group desc for online growth */
1105         /*
1106          * Journaling support valid if EXT4_FEATURE_COMPAT_HAS_JOURNAL set.
1107          */
1108 /*D0*/  __u8    s_journal_uuid[16];     /* uuid of journal superblock */
1109 /*E0*/  __le32  s_journal_inum;         /* inode number of journal file */
1110         __le32  s_journal_dev;          /* device number of journal file */
1111         __le32  s_last_orphan;          /* start of list of inodes to delete */
1112         __le32  s_hash_seed[4];         /* HTREE hash seed */
1113         __u8    s_def_hash_version;     /* Default hash version to use */
1114         __u8    s_jnl_backup_type;
1115         __le16  s_desc_size;            /* size of group descriptor */
1116 /*100*/ __le32  s_default_mount_opts;
1117         __le32  s_first_meta_bg;        /* First metablock block group */
1118         __le32  s_mkfs_time;            /* When the filesystem was created */
1119         __le32  s_jnl_blocks[17];       /* Backup of the journal inode */
1120         /* 64bit support valid if EXT4_FEATURE_COMPAT_64BIT */
1121 /*150*/ __le32  s_blocks_count_hi;      /* Blocks count */
1122         __le32  s_r_blocks_count_hi;    /* Reserved blocks count */
1123         __le32  s_free_blocks_count_hi; /* Free blocks count */
1124         __le16  s_min_extra_isize;      /* All inodes have at least # bytes */
1125         __le16  s_want_extra_isize;     /* New inodes should reserve # bytes */
1126         __le32  s_flags;                /* Miscellaneous flags */
1127         __le16  s_raid_stride;          /* RAID stride */
1128         __le16  s_mmp_update_interval;  /* # seconds to wait in MMP checking */
1129         __le64  s_mmp_block;            /* Block for multi-mount protection */
1130         __le32  s_raid_stripe_width;    /* blocks on all data disks (N*stride)*/
1131         __u8    s_log_groups_per_flex;  /* FLEX_BG group size */
1132         __u8    s_checksum_type;        /* metadata checksum algorithm used */
1133         __le16  s_reserved_pad;
1134         __le64  s_kbytes_written;       /* nr of lifetime kilobytes written */
1135         __le32  s_snapshot_inum;        /* Inode number of active snapshot */
1136         __le32  s_snapshot_id;          /* sequential ID of active snapshot */
1137         __le64  s_snapshot_r_blocks_count; /* reserved blocks for active
1138                                               snapshot's future use */
1139         __le32  s_snapshot_list;        /* inode number of the head of the
1140                                            on-disk snapshot list */
1141 #define EXT4_S_ERR_START offsetof(struct ext4_super_block, s_error_count)
1142         __le32  s_error_count;          /* number of fs errors */
1143         __le32  s_first_error_time;     /* first time an error happened */
1144         __le32  s_first_error_ino;      /* inode involved in first error */
1145         __le64  s_first_error_block;    /* block involved of first error */
1146         __u8    s_first_error_func[32]; /* function where the error happened */
1147         __le32  s_first_error_line;     /* line number where error happened */
1148         __le32  s_last_error_time;      /* most recent time of an error */
1149         __le32  s_last_error_ino;       /* inode involved in last error */
1150         __le32  s_last_error_line;      /* line number where error happened */
1151         __le64  s_last_error_block;     /* block involved of last error */
1152         __u8    s_last_error_func[32];  /* function where the error happened */
1153 #define EXT4_S_ERR_END offsetof(struct ext4_super_block, s_mount_opts)
1154         __u8    s_mount_opts[64];
1155         __le32  s_usr_quota_inum;       /* inode for tracking user quota */
1156         __le32  s_grp_quota_inum;       /* inode for tracking group quota */
1157         __le32  s_overhead_clusters;    /* overhead blocks/clusters in fs */
1158         __le32  s_backup_bgs[2];        /* groups with sparse_super2 SBs */
1159         __le32  s_reserved[106];        /* Padding to the end of the block */
1160         __le32  s_checksum;             /* crc32c(superblock) */
1161 };
1162
1163 #define EXT4_S_ERR_LEN (EXT4_S_ERR_END - EXT4_S_ERR_START)
1164
1165 #ifdef __KERNEL__
1166
1167 /*
1168  * run-time mount flags
1169  */
1170 #define EXT4_MF_MNTDIR_SAMPLED  0x0001
1171 #define EXT4_MF_FS_ABORTED      0x0002  /* Fatal error detected */
1172
1173 /* Number of quota types we support */
1174 #define EXT4_MAXQUOTAS 2
1175
1176 /*
1177  * fourth extended-fs super-block data in memory
1178  */
1179 struct ext4_sb_info {
1180         unsigned long s_desc_size;      /* Size of a group descriptor in bytes */
1181         unsigned long s_inodes_per_block;/* Number of inodes per block */
1182         unsigned long s_blocks_per_group;/* Number of blocks in a group */
1183         unsigned long s_clusters_per_group; /* Number of clusters in a group */
1184         unsigned long s_inodes_per_group;/* Number of inodes in a group */
1185         unsigned long s_itb_per_group;  /* Number of inode table blocks per group */
1186         unsigned long s_gdb_count;      /* Number of group descriptor blocks */
1187         unsigned long s_desc_per_block; /* Number of group descriptors per block */
1188         ext4_group_t s_groups_count;    /* Number of groups in the fs */
1189         ext4_group_t s_blockfile_groups;/* Groups acceptable for non-extent files */
1190         unsigned long s_overhead;  /* # of fs overhead clusters */
1191         unsigned int s_cluster_ratio;   /* Number of blocks per cluster */
1192         unsigned int s_cluster_bits;    /* log2 of s_cluster_ratio */
1193         loff_t s_bitmap_maxbytes;       /* max bytes for bitmap files */
1194         struct buffer_head * s_sbh;     /* Buffer containing the super block */
1195         struct ext4_super_block *s_es;  /* Pointer to the super block in the buffer */
1196         struct buffer_head **s_group_desc;
1197         unsigned int s_mount_opt;
1198         unsigned int s_mount_opt2;
1199         unsigned int s_mount_flags;
1200         unsigned int s_def_mount_opt;
1201         ext4_fsblk_t s_sb_block;
1202         atomic64_t s_resv_clusters;
1203         kuid_t s_resuid;
1204         kgid_t s_resgid;
1205         unsigned short s_mount_state;
1206         unsigned short s_pad;
1207         int s_addr_per_block_bits;
1208         int s_desc_per_block_bits;
1209         int s_inode_size;
1210         int s_first_ino;
1211         unsigned int s_inode_readahead_blks;
1212         unsigned int s_inode_goal;
1213         spinlock_t s_next_gen_lock;
1214         u32 s_next_generation;
1215         u32 s_hash_seed[4];
1216         int s_def_hash_version;
1217         int s_hash_unsigned;    /* 3 if hash should be signed, 0 if not */
1218         struct percpu_counter s_freeclusters_counter;
1219         struct percpu_counter s_freeinodes_counter;
1220         struct percpu_counter s_dirs_counter;
1221         struct percpu_counter s_dirtyclusters_counter;
1222         struct blockgroup_lock *s_blockgroup_lock;
1223         struct proc_dir_entry *s_proc;
1224         struct kobject s_kobj;
1225         struct completion s_kobj_unregister;
1226         struct super_block *s_sb;
1227
1228         /* Journaling */
1229         struct journal_s *s_journal;
1230         struct list_head s_orphan;
1231         struct mutex s_orphan_lock;
1232         unsigned long s_resize_flags;           /* Flags indicating if there
1233                                                    is a resizer */
1234         unsigned long s_commit_interval;
1235         u32 s_max_batch_time;
1236         u32 s_min_batch_time;
1237         struct block_device *journal_bdev;
1238 #ifdef CONFIG_QUOTA
1239         char *s_qf_names[EXT4_MAXQUOTAS];       /* Names of quota files with journalled quota */
1240         int s_jquota_fmt;                       /* Format of quota to use */
1241 #endif
1242         unsigned int s_want_extra_isize; /* New inodes should reserve # bytes */
1243         struct rb_root system_blks;
1244
1245 #ifdef EXTENTS_STATS
1246         /* ext4 extents stats */
1247         unsigned long s_ext_min;
1248         unsigned long s_ext_max;
1249         unsigned long s_depth_max;
1250         spinlock_t s_ext_stats_lock;
1251         unsigned long s_ext_blocks;
1252         unsigned long s_ext_extents;
1253 #endif
1254
1255         /* for buddy allocator */
1256         struct ext4_group_info ***s_group_info;
1257         struct inode *s_buddy_cache;
1258         spinlock_t s_md_lock;
1259         unsigned short *s_mb_offsets;
1260         unsigned int *s_mb_maxs;
1261         unsigned int s_group_info_size;
1262
1263         /* tunables */
1264         unsigned long s_stripe;
1265         unsigned int s_mb_stream_request;
1266         unsigned int s_mb_max_to_scan;
1267         unsigned int s_mb_min_to_scan;
1268         unsigned int s_mb_stats;
1269         unsigned int s_mb_order2_reqs;
1270         unsigned int s_mb_group_prealloc;
1271         unsigned int s_max_dir_size_kb;
1272         /* where last allocation was done - for stream allocation */
1273         unsigned long s_mb_last_group;
1274         unsigned long s_mb_last_start;
1275
1276         /* stats for buddy allocator */
1277         atomic_t s_bal_reqs;    /* number of reqs with len > 1 */
1278         atomic_t s_bal_success; /* we found long enough chunks */
1279         atomic_t s_bal_allocated;       /* in blocks */
1280         atomic_t s_bal_ex_scanned;      /* total extents scanned */
1281         atomic_t s_bal_goals;   /* goal hits */
1282         atomic_t s_bal_breaks;  /* too long searches */
1283         atomic_t s_bal_2orders; /* 2^order hits */
1284         spinlock_t s_bal_lock;
1285         unsigned long s_mb_buddies_generated;
1286         unsigned long long s_mb_generation_time;
1287         atomic_t s_mb_lost_chunks;
1288         atomic_t s_mb_preallocated;
1289         atomic_t s_mb_discarded;
1290         atomic_t s_lock_busy;
1291
1292         /* locality groups */
1293         struct ext4_locality_group __percpu *s_locality_groups;
1294
1295         /* for write statistics */
1296         unsigned long s_sectors_written_start;
1297         u64 s_kbytes_written;
1298
1299         /* the size of zero-out chunk */
1300         unsigned int s_extent_max_zeroout_kb;
1301
1302         unsigned int s_log_groups_per_flex;
1303         struct flex_groups *s_flex_groups;
1304         ext4_group_t s_flex_groups_allocated;
1305
1306         /* workqueue for reserved extent conversions (buffered io) */
1307         struct workqueue_struct *rsv_conversion_wq;
1308
1309         /* timer for periodic error stats printing */
1310         struct timer_list s_err_report;
1311
1312         /* Lazy inode table initialization info */
1313         struct ext4_li_request *s_li_request;
1314         /* Wait multiplier for lazy initialization thread */
1315         unsigned int s_li_wait_mult;
1316
1317         /* Kernel thread for multiple mount protection */
1318         struct task_struct *s_mmp_tsk;
1319
1320         /* record the last minlen when FITRIM is called. */
1321         atomic_t s_last_trim_minblks;
1322
1323         /* Reference to checksum algorithm driver via cryptoapi */
1324         struct crypto_shash *s_chksum_driver;
1325
1326         /* Precomputed FS UUID checksum for seeding other checksums */
1327         __u32 s_csum_seed;
1328
1329         /* Reclaim extents from extent status tree */
1330         struct shrinker s_es_shrinker;
1331         struct list_head s_es_list;     /* List of inodes with reclaimable extents */
1332         long s_es_nr_inode;
1333         struct ext4_es_stats s_es_stats;
1334         struct mb_cache *s_mb_cache;
1335         spinlock_t s_es_lock ____cacheline_aligned_in_smp;
1336
1337         /* Ratelimit ext4 messages. */
1338         struct ratelimit_state s_err_ratelimit_state;
1339         struct ratelimit_state s_warning_ratelimit_state;
1340         struct ratelimit_state s_msg_ratelimit_state;
1341 };
1342
1343 static inline struct ext4_sb_info *EXT4_SB(struct super_block *sb)
1344 {
1345         return sb->s_fs_info;
1346 }
1347 static inline struct ext4_inode_info *EXT4_I(struct inode *inode)
1348 {
1349         return container_of(inode, struct ext4_inode_info, vfs_inode);
1350 }
1351
1352 static inline struct timespec ext4_current_time(struct inode *inode)
1353 {
1354         return (inode->i_sb->s_time_gran < NSEC_PER_SEC) ?
1355                 current_fs_time(inode->i_sb) : CURRENT_TIME_SEC;
1356 }
1357
1358 static inline int ext4_valid_inum(struct super_block *sb, unsigned long ino)
1359 {
1360         return ino == EXT4_ROOT_INO ||
1361                 ino == EXT4_USR_QUOTA_INO ||
1362                 ino == EXT4_GRP_QUOTA_INO ||
1363                 ino == EXT4_BOOT_LOADER_INO ||
1364                 ino == EXT4_JOURNAL_INO ||
1365                 ino == EXT4_RESIZE_INO ||
1366                 (ino >= EXT4_FIRST_INO(sb) &&
1367                  ino <= le32_to_cpu(EXT4_SB(sb)->s_es->s_inodes_count));
1368 }
1369
1370 static inline void ext4_set_io_unwritten_flag(struct inode *inode,
1371                                               struct ext4_io_end *io_end)
1372 {
1373         if (!(io_end->flag & EXT4_IO_END_UNWRITTEN)) {
1374                 io_end->flag |= EXT4_IO_END_UNWRITTEN;
1375                 atomic_inc(&EXT4_I(inode)->i_unwritten);
1376         }
1377 }
1378
1379 static inline ext4_io_end_t *ext4_inode_aio(struct inode *inode)
1380 {
1381         return inode->i_private;
1382 }
1383
1384 static inline void ext4_inode_aio_set(struct inode *inode, ext4_io_end_t *io)
1385 {
1386         inode->i_private = io;
1387 }
1388
1389 /*
1390  * Inode dynamic state flags
1391  */
1392 enum {
1393         EXT4_STATE_JDATA,               /* journaled data exists */
1394         EXT4_STATE_NEW,                 /* inode is newly created */
1395         EXT4_STATE_XATTR,               /* has in-inode xattrs */
1396         EXT4_STATE_NO_EXPAND,           /* No space for expansion */
1397         EXT4_STATE_DA_ALLOC_CLOSE,      /* Alloc DA blks on close */
1398         EXT4_STATE_EXT_MIGRATE,         /* Inode is migrating */
1399         EXT4_STATE_DIO_UNWRITTEN,       /* need convert on dio done*/
1400         EXT4_STATE_NEWENTRY,            /* File just added to dir */
1401         EXT4_STATE_DIOREAD_LOCK,        /* Disable support for dio read
1402                                            nolocking */
1403         EXT4_STATE_MAY_INLINE_DATA,     /* may have in-inode data */
1404         EXT4_STATE_ORDERED_MODE,        /* data=ordered mode */
1405         EXT4_STATE_EXT_PRECACHED,       /* extents have been precached */
1406 };
1407
1408 #define EXT4_INODE_BIT_FNS(name, field, offset)                         \
1409 static inline int ext4_test_inode_##name(struct inode *inode, int bit)  \
1410 {                                                                       \
1411         return test_bit(bit + (offset), &EXT4_I(inode)->i_##field);     \
1412 }                                                                       \
1413 static inline void ext4_set_inode_##name(struct inode *inode, int bit)  \
1414 {                                                                       \
1415         set_bit(bit + (offset), &EXT4_I(inode)->i_##field);             \
1416 }                                                                       \
1417 static inline void ext4_clear_inode_##name(struct inode *inode, int bit) \
1418 {                                                                       \
1419         clear_bit(bit + (offset), &EXT4_I(inode)->i_##field);           \
1420 }
1421
1422 /* Add these declarations here only so that these functions can be
1423  * found by name.  Otherwise, they are very hard to locate. */
1424 static inline int ext4_test_inode_flag(struct inode *inode, int bit);
1425 static inline void ext4_set_inode_flag(struct inode *inode, int bit);
1426 static inline void ext4_clear_inode_flag(struct inode *inode, int bit);
1427 EXT4_INODE_BIT_FNS(flag, flags, 0)
1428
1429 /* Add these declarations here only so that these functions can be
1430  * found by name.  Otherwise, they are very hard to locate. */
1431 static inline int ext4_test_inode_state(struct inode *inode, int bit);
1432 static inline void ext4_set_inode_state(struct inode *inode, int bit);
1433 static inline void ext4_clear_inode_state(struct inode *inode, int bit);
1434 #if (BITS_PER_LONG < 64)
1435 EXT4_INODE_BIT_FNS(state, state_flags, 0)
1436
1437 static inline void ext4_clear_state_flags(struct ext4_inode_info *ei)
1438 {
1439         (ei)->i_state_flags = 0;
1440 }
1441 #else
1442 EXT4_INODE_BIT_FNS(state, flags, 32)
1443
1444 static inline void ext4_clear_state_flags(struct ext4_inode_info *ei)
1445 {
1446         /* We depend on the fact that callers will set i_flags */
1447 }
1448 #endif
1449 #else
1450 /* Assume that user mode programs are passing in an ext4fs superblock, not
1451  * a kernel struct super_block.  This will allow us to call the feature-test
1452  * macros from user land. */
1453 #define EXT4_SB(sb)     (sb)
1454 #endif
1455
1456 #define NEXT_ORPHAN(inode) EXT4_I(inode)->i_dtime
1457
1458 /*
1459  * Codes for operating systems
1460  */
1461 #define EXT4_OS_LINUX           0
1462 #define EXT4_OS_HURD            1
1463 #define EXT4_OS_MASIX           2
1464 #define EXT4_OS_FREEBSD         3
1465 #define EXT4_OS_LITES           4
1466
1467 /*
1468  * Revision levels
1469  */
1470 #define EXT4_GOOD_OLD_REV       0       /* The good old (original) format */
1471 #define EXT4_DYNAMIC_REV        1       /* V2 format w/ dynamic inode sizes */
1472
1473 #define EXT4_CURRENT_REV        EXT4_GOOD_OLD_REV
1474 #define EXT4_MAX_SUPP_REV       EXT4_DYNAMIC_REV
1475
1476 #define EXT4_GOOD_OLD_INODE_SIZE 128
1477
1478 /*
1479  * Feature set definitions
1480  */
1481
1482 #define EXT4_HAS_COMPAT_FEATURE(sb,mask)                        \
1483         ((EXT4_SB(sb)->s_es->s_feature_compat & cpu_to_le32(mask)) != 0)
1484 #define EXT4_HAS_RO_COMPAT_FEATURE(sb,mask)                     \
1485         ((EXT4_SB(sb)->s_es->s_feature_ro_compat & cpu_to_le32(mask)) != 0)
1486 #define EXT4_HAS_INCOMPAT_FEATURE(sb,mask)                      \
1487         ((EXT4_SB(sb)->s_es->s_feature_incompat & cpu_to_le32(mask)) != 0)
1488 #define EXT4_SET_COMPAT_FEATURE(sb,mask)                        \
1489         EXT4_SB(sb)->s_es->s_feature_compat |= cpu_to_le32(mask)
1490 #define EXT4_SET_RO_COMPAT_FEATURE(sb,mask)                     \
1491         EXT4_SB(sb)->s_es->s_feature_ro_compat |= cpu_to_le32(mask)
1492 #define EXT4_SET_INCOMPAT_FEATURE(sb,mask)                      \
1493         EXT4_SB(sb)->s_es->s_feature_incompat |= cpu_to_le32(mask)
1494 #define EXT4_CLEAR_COMPAT_FEATURE(sb,mask)                      \
1495         EXT4_SB(sb)->s_es->s_feature_compat &= ~cpu_to_le32(mask)
1496 #define EXT4_CLEAR_RO_COMPAT_FEATURE(sb,mask)                   \
1497         EXT4_SB(sb)->s_es->s_feature_ro_compat &= ~cpu_to_le32(mask)
1498 #define EXT4_CLEAR_INCOMPAT_FEATURE(sb,mask)                    \
1499         EXT4_SB(sb)->s_es->s_feature_incompat &= ~cpu_to_le32(mask)
1500
1501 #define EXT4_FEATURE_COMPAT_DIR_PREALLOC        0x0001
1502 #define EXT4_FEATURE_COMPAT_IMAGIC_INODES       0x0002
1503 #define EXT4_FEATURE_COMPAT_HAS_JOURNAL         0x0004
1504 #define EXT4_FEATURE_COMPAT_EXT_ATTR            0x0008
1505 #define EXT4_FEATURE_COMPAT_RESIZE_INODE        0x0010
1506 #define EXT4_FEATURE_COMPAT_DIR_INDEX           0x0020
1507 #define EXT4_FEATURE_COMPAT_SPARSE_SUPER2       0x0200
1508
1509 #define EXT4_FEATURE_RO_COMPAT_SPARSE_SUPER     0x0001
1510 #define EXT4_FEATURE_RO_COMPAT_LARGE_FILE       0x0002
1511 #define EXT4_FEATURE_RO_COMPAT_BTREE_DIR        0x0004
1512 #define EXT4_FEATURE_RO_COMPAT_HUGE_FILE        0x0008
1513 #define EXT4_FEATURE_RO_COMPAT_GDT_CSUM         0x0010
1514 #define EXT4_FEATURE_RO_COMPAT_DIR_NLINK        0x0020
1515 #define EXT4_FEATURE_RO_COMPAT_EXTRA_ISIZE      0x0040
1516 #define EXT4_FEATURE_RO_COMPAT_QUOTA            0x0100
1517 #define EXT4_FEATURE_RO_COMPAT_BIGALLOC         0x0200
1518 /*
1519  * METADATA_CSUM also enables group descriptor checksums (GDT_CSUM).  When
1520  * METADATA_CSUM is set, group descriptor checksums use the same algorithm as
1521  * all other data structures' checksums.  However, the METADATA_CSUM and
1522  * GDT_CSUM bits are mutually exclusive.
1523  */
1524 #define EXT4_FEATURE_RO_COMPAT_METADATA_CSUM    0x0400
1525
1526 #define EXT4_FEATURE_INCOMPAT_COMPRESSION       0x0001
1527 #define EXT4_FEATURE_INCOMPAT_FILETYPE          0x0002
1528 #define EXT4_FEATURE_INCOMPAT_RECOVER           0x0004 /* Needs recovery */
1529 #define EXT4_FEATURE_INCOMPAT_JOURNAL_DEV       0x0008 /* Journal device */
1530 #define EXT4_FEATURE_INCOMPAT_META_BG           0x0010
1531 #define EXT4_FEATURE_INCOMPAT_EXTENTS           0x0040 /* extents support */
1532 #define EXT4_FEATURE_INCOMPAT_64BIT             0x0080
1533 #define EXT4_FEATURE_INCOMPAT_MMP               0x0100
1534 #define EXT4_FEATURE_INCOMPAT_FLEX_BG           0x0200
1535 #define EXT4_FEATURE_INCOMPAT_EA_INODE          0x0400 /* EA in inode */
1536 #define EXT4_FEATURE_INCOMPAT_DIRDATA           0x1000 /* data in dirent */
1537 #define EXT4_FEATURE_INCOMPAT_BG_USE_META_CSUM  0x2000 /* use crc32c for bg */
1538 #define EXT4_FEATURE_INCOMPAT_LARGEDIR          0x4000 /* >2GB or 3-lvl htree */
1539 #define EXT4_FEATURE_INCOMPAT_INLINE_DATA       0x8000 /* data in inode */
1540
1541 #define EXT2_FEATURE_COMPAT_SUPP        EXT4_FEATURE_COMPAT_EXT_ATTR
1542 #define EXT2_FEATURE_INCOMPAT_SUPP      (EXT4_FEATURE_INCOMPAT_FILETYPE| \
1543                                          EXT4_FEATURE_INCOMPAT_META_BG)
1544 #define EXT2_FEATURE_RO_COMPAT_SUPP     (EXT4_FEATURE_RO_COMPAT_SPARSE_SUPER| \
1545                                          EXT4_FEATURE_RO_COMPAT_LARGE_FILE| \
1546                                          EXT4_FEATURE_RO_COMPAT_BTREE_DIR)
1547
1548 #define EXT3_FEATURE_COMPAT_SUPP        EXT4_FEATURE_COMPAT_EXT_ATTR
1549 #define EXT3_FEATURE_INCOMPAT_SUPP      (EXT4_FEATURE_INCOMPAT_FILETYPE| \
1550                                          EXT4_FEATURE_INCOMPAT_RECOVER| \
1551                                          EXT4_FEATURE_INCOMPAT_META_BG)
1552 #define EXT3_FEATURE_RO_COMPAT_SUPP     (EXT4_FEATURE_RO_COMPAT_SPARSE_SUPER| \
1553                                          EXT4_FEATURE_RO_COMPAT_LARGE_FILE| \
1554                                          EXT4_FEATURE_RO_COMPAT_BTREE_DIR)
1555
1556 #define EXT4_FEATURE_COMPAT_SUPP        EXT2_FEATURE_COMPAT_EXT_ATTR
1557 #define EXT4_FEATURE_INCOMPAT_SUPP      (EXT4_FEATURE_INCOMPAT_FILETYPE| \
1558                                          EXT4_FEATURE_INCOMPAT_RECOVER| \
1559                                          EXT4_FEATURE_INCOMPAT_META_BG| \
1560                                          EXT4_FEATURE_INCOMPAT_EXTENTS| \
1561                                          EXT4_FEATURE_INCOMPAT_64BIT| \
1562                                          EXT4_FEATURE_INCOMPAT_FLEX_BG| \
1563                                          EXT4_FEATURE_INCOMPAT_MMP |    \
1564                                          EXT4_FEATURE_INCOMPAT_INLINE_DATA)
1565 #define EXT4_FEATURE_RO_COMPAT_SUPP     (EXT4_FEATURE_RO_COMPAT_SPARSE_SUPER| \
1566                                          EXT4_FEATURE_RO_COMPAT_LARGE_FILE| \
1567                                          EXT4_FEATURE_RO_COMPAT_GDT_CSUM| \
1568                                          EXT4_FEATURE_RO_COMPAT_DIR_NLINK | \
1569                                          EXT4_FEATURE_RO_COMPAT_EXTRA_ISIZE | \
1570                                          EXT4_FEATURE_RO_COMPAT_BTREE_DIR |\
1571                                          EXT4_FEATURE_RO_COMPAT_HUGE_FILE |\
1572                                          EXT4_FEATURE_RO_COMPAT_BIGALLOC |\
1573                                          EXT4_FEATURE_RO_COMPAT_METADATA_CSUM|\
1574                                          EXT4_FEATURE_RO_COMPAT_QUOTA)
1575
1576 /*
1577  * Default values for user and/or group using reserved blocks
1578  */
1579 #define EXT4_DEF_RESUID         0
1580 #define EXT4_DEF_RESGID         0
1581
1582 #define EXT4_DEF_INODE_READAHEAD_BLKS   32
1583
1584 /*
1585  * Default mount options
1586  */
1587 #define EXT4_DEFM_DEBUG         0x0001
1588 #define EXT4_DEFM_BSDGROUPS     0x0002
1589 #define EXT4_DEFM_XATTR_USER    0x0004
1590 #define EXT4_DEFM_ACL           0x0008
1591 #define EXT4_DEFM_UID16         0x0010
1592 #define EXT4_DEFM_JMODE         0x0060
1593 #define EXT4_DEFM_JMODE_DATA    0x0020
1594 #define EXT4_DEFM_JMODE_ORDERED 0x0040
1595 #define EXT4_DEFM_JMODE_WBACK   0x0060
1596 #define EXT4_DEFM_NOBARRIER     0x0100
1597 #define EXT4_DEFM_BLOCK_VALIDITY 0x0200
1598 #define EXT4_DEFM_DISCARD       0x0400
1599 #define EXT4_DEFM_NODELALLOC    0x0800
1600
1601 /*
1602  * Default journal batch times
1603  */
1604 #define EXT4_DEF_MIN_BATCH_TIME 0
1605 #define EXT4_DEF_MAX_BATCH_TIME 15000 /* 15ms */
1606
1607 /*
1608  * Minimum number of groups in a flexgroup before we separate out
1609  * directories into the first block group of a flexgroup
1610  */
1611 #define EXT4_FLEX_SIZE_DIR_ALLOC_SCHEME 4
1612
1613 /*
1614  * Structure of a directory entry
1615  */
1616 #define EXT4_NAME_LEN 255
1617
1618 struct ext4_dir_entry {
1619         __le32  inode;                  /* Inode number */
1620         __le16  rec_len;                /* Directory entry length */
1621         __le16  name_len;               /* Name length */
1622         char    name[EXT4_NAME_LEN];    /* File name */
1623 };
1624
1625 /*
1626  * The new version of the directory entry.  Since EXT4 structures are
1627  * stored in intel byte order, and the name_len field could never be
1628  * bigger than 255 chars, it's safe to reclaim the extra byte for the
1629  * file_type field.
1630  */
1631 struct ext4_dir_entry_2 {
1632         __le32  inode;                  /* Inode number */
1633         __le16  rec_len;                /* Directory entry length */
1634         __u8    name_len;               /* Name length */
1635         __u8    file_type;
1636         char    name[EXT4_NAME_LEN];    /* File name */
1637 };
1638
1639 /*
1640  * This is a bogus directory entry at the end of each leaf block that
1641  * records checksums.
1642  */
1643 struct ext4_dir_entry_tail {
1644         __le32  det_reserved_zero1;     /* Pretend to be unused */
1645         __le16  det_rec_len;            /* 12 */
1646         __u8    det_reserved_zero2;     /* Zero name length */
1647         __u8    det_reserved_ft;        /* 0xDE, fake file type */
1648         __le32  det_checksum;           /* crc32c(uuid+inum+dirblock) */
1649 };
1650
1651 #define EXT4_DIRENT_TAIL(block, blocksize) \
1652         ((struct ext4_dir_entry_tail *)(((void *)(block)) + \
1653                                         ((blocksize) - \
1654                                          sizeof(struct ext4_dir_entry_tail))))
1655
1656 /*
1657  * Ext4 directory file types.  Only the low 3 bits are used.  The
1658  * other bits are reserved for now.
1659  */
1660 #define EXT4_FT_UNKNOWN         0
1661 #define EXT4_FT_REG_FILE        1
1662 #define EXT4_FT_DIR             2
1663 #define EXT4_FT_CHRDEV          3
1664 #define EXT4_FT_BLKDEV          4
1665 #define EXT4_FT_FIFO            5
1666 #define EXT4_FT_SOCK            6
1667 #define EXT4_FT_SYMLINK         7
1668
1669 #define EXT4_FT_MAX             8
1670
1671 #define EXT4_FT_DIR_CSUM        0xDE
1672
1673 /*
1674  * EXT4_DIR_PAD defines the directory entries boundaries
1675  *
1676  * NOTE: It must be a multiple of 4
1677  */
1678 #define EXT4_DIR_PAD                    4
1679 #define EXT4_DIR_ROUND                  (EXT4_DIR_PAD - 1)
1680 #define EXT4_DIR_REC_LEN(name_len)      (((name_len) + 8 + EXT4_DIR_ROUND) & \
1681                                          ~EXT4_DIR_ROUND)
1682 #define EXT4_MAX_REC_LEN                ((1<<16)-1)
1683
1684 /*
1685  * If we ever get support for fs block sizes > page_size, we'll need
1686  * to remove the #if statements in the next two functions...
1687  */
1688 static inline unsigned int
1689 ext4_rec_len_from_disk(__le16 dlen, unsigned blocksize)
1690 {
1691         unsigned len = le16_to_cpu(dlen);
1692
1693 #if (PAGE_CACHE_SIZE >= 65536)
1694         if (len == EXT4_MAX_REC_LEN || len == 0)
1695                 return blocksize;
1696         return (len & 65532) | ((len & 3) << 16);
1697 #else
1698         return len;
1699 #endif
1700 }
1701
1702 static inline __le16 ext4_rec_len_to_disk(unsigned len, unsigned blocksize)
1703 {
1704         if ((len > blocksize) || (blocksize > (1 << 18)) || (len & 3))
1705                 BUG();
1706 #if (PAGE_CACHE_SIZE >= 65536)
1707         if (len < 65536)
1708                 return cpu_to_le16(len);
1709         if (len == blocksize) {
1710                 if (blocksize == 65536)
1711                         return cpu_to_le16(EXT4_MAX_REC_LEN);
1712                 else
1713                         return cpu_to_le16(0);
1714         }
1715         return cpu_to_le16((len & 65532) | ((len >> 16) & 3));
1716 #else
1717         return cpu_to_le16(len);
1718 #endif
1719 }
1720
1721 /*
1722  * Hash Tree Directory indexing
1723  * (c) Daniel Phillips, 2001
1724  */
1725
1726 #define is_dx(dir) (EXT4_HAS_COMPAT_FEATURE(dir->i_sb, \
1727                                       EXT4_FEATURE_COMPAT_DIR_INDEX) && \
1728                     ext4_test_inode_flag((dir), EXT4_INODE_INDEX))
1729 #define EXT4_DIR_LINK_MAX(dir) (!is_dx(dir) && (dir)->i_nlink >= EXT4_LINK_MAX)
1730 #define EXT4_DIR_LINK_EMPTY(dir) ((dir)->i_nlink == 2 || (dir)->i_nlink == 1)
1731
1732 /* Legal values for the dx_root hash_version field: */
1733
1734 #define DX_HASH_LEGACY          0
1735 #define DX_HASH_HALF_MD4        1
1736 #define DX_HASH_TEA             2
1737 #define DX_HASH_LEGACY_UNSIGNED 3
1738 #define DX_HASH_HALF_MD4_UNSIGNED       4
1739 #define DX_HASH_TEA_UNSIGNED            5
1740
1741 static inline u32 ext4_chksum(struct ext4_sb_info *sbi, u32 crc,
1742                               const void *address, unsigned int length)
1743 {
1744         struct {
1745                 struct shash_desc shash;
1746                 char ctx[4];
1747         } desc;
1748         int err;
1749
1750         BUG_ON(crypto_shash_descsize(sbi->s_chksum_driver)!=sizeof(desc.ctx));
1751
1752         desc.shash.tfm = sbi->s_chksum_driver;
1753         desc.shash.flags = 0;
1754         *(u32 *)desc.ctx = crc;
1755
1756         err = crypto_shash_update(&desc.shash, address, length);
1757         BUG_ON(err);
1758
1759         return *(u32 *)desc.ctx;
1760 }
1761
1762 #ifdef __KERNEL__
1763
1764 /* hash info structure used by the directory hash */
1765 struct dx_hash_info
1766 {
1767         u32             hash;
1768         u32             minor_hash;
1769         int             hash_version;
1770         u32             *seed;
1771 };
1772
1773
1774 /* 32 and 64 bit signed EOF for dx directories */
1775 #define EXT4_HTREE_EOF_32BIT   ((1UL  << (32 - 1)) - 1)
1776 #define EXT4_HTREE_EOF_64BIT   ((1ULL << (64 - 1)) - 1)
1777
1778
1779 /*
1780  * Control parameters used by ext4_htree_next_block
1781  */
1782 #define HASH_NB_ALWAYS          1
1783
1784
1785 /*
1786  * Describe an inode's exact location on disk and in memory
1787  */
1788 struct ext4_iloc
1789 {
1790         struct buffer_head *bh;
1791         unsigned long offset;
1792         ext4_group_t block_group;
1793 };
1794
1795 static inline struct ext4_inode *ext4_raw_inode(struct ext4_iloc *iloc)
1796 {
1797         return (struct ext4_inode *) (iloc->bh->b_data + iloc->offset);
1798 }
1799
1800 /*
1801  * This structure is stuffed into the struct file's private_data field
1802  * for directories.  It is where we put information so that we can do
1803  * readdir operations in hash tree order.
1804  */
1805 struct dir_private_info {
1806         struct rb_root  root;
1807         struct rb_node  *curr_node;
1808         struct fname    *extra_fname;
1809         loff_t          last_pos;
1810         __u32           curr_hash;
1811         __u32           curr_minor_hash;
1812         __u32           next_hash;
1813 };
1814
1815 /* calculate the first block number of the group */
1816 static inline ext4_fsblk_t
1817 ext4_group_first_block_no(struct super_block *sb, ext4_group_t group_no)
1818 {
1819         return group_no * (ext4_fsblk_t)EXT4_BLOCKS_PER_GROUP(sb) +
1820                 le32_to_cpu(EXT4_SB(sb)->s_es->s_first_data_block);
1821 }
1822
1823 /*
1824  * Special error return code only used by dx_probe() and its callers.
1825  */
1826 #define ERR_BAD_DX_DIR  (-(MAX_ERRNO - 1))
1827
1828 /*
1829  * Timeout and state flag for lazy initialization inode thread.
1830  */
1831 #define EXT4_DEF_LI_WAIT_MULT                   10
1832 #define EXT4_DEF_LI_MAX_START_DELAY             5
1833 #define EXT4_LAZYINIT_QUIT                      0x0001
1834 #define EXT4_LAZYINIT_RUNNING                   0x0002
1835
1836 /*
1837  * Lazy inode table initialization info
1838  */
1839 struct ext4_lazy_init {
1840         unsigned long           li_state;
1841         struct list_head        li_request_list;
1842         struct mutex            li_list_mtx;
1843 };
1844
1845 struct ext4_li_request {
1846         struct super_block      *lr_super;
1847         struct ext4_sb_info     *lr_sbi;
1848         ext4_group_t            lr_next_group;
1849         struct list_head        lr_request;
1850         unsigned long           lr_next_sched;
1851         unsigned long           lr_timeout;
1852 };
1853
1854 struct ext4_features {
1855         struct kobject f_kobj;
1856         struct completion f_kobj_unregister;
1857 };
1858
1859 /*
1860  * This structure will be used for multiple mount protection. It will be
1861  * written into the block number saved in the s_mmp_block field in the
1862  * superblock. Programs that check MMP should assume that if
1863  * SEQ_FSCK (or any unknown code above SEQ_MAX) is present then it is NOT safe
1864  * to use the filesystem, regardless of how old the timestamp is.
1865  */
1866 #define EXT4_MMP_MAGIC     0x004D4D50U /* ASCII for MMP */
1867 #define EXT4_MMP_SEQ_CLEAN 0xFF4D4D50U /* mmp_seq value for clean unmount */
1868 #define EXT4_MMP_SEQ_FSCK  0xE24D4D50U /* mmp_seq value when being fscked */
1869 #define EXT4_MMP_SEQ_MAX   0xE24D4D4FU /* maximum valid mmp_seq value */
1870
1871 struct mmp_struct {
1872         __le32  mmp_magic;              /* Magic number for MMP */
1873         __le32  mmp_seq;                /* Sequence no. updated periodically */
1874
1875         /*
1876          * mmp_time, mmp_nodename & mmp_bdevname are only used for information
1877          * purposes and do not affect the correctness of the algorithm
1878          */
1879         __le64  mmp_time;               /* Time last updated */
1880         char    mmp_nodename[64];       /* Node which last updated MMP block */
1881         char    mmp_bdevname[32];       /* Bdev which last updated MMP block */
1882
1883         /*
1884          * mmp_check_interval is used to verify if the MMP block has been
1885          * updated on the block device. The value is updated based on the
1886          * maximum time to write the MMP block during an update cycle.
1887          */
1888         __le16  mmp_check_interval;
1889
1890         __le16  mmp_pad1;
1891         __le32  mmp_pad2[226];
1892         __le32  mmp_checksum;           /* crc32c(uuid+mmp_block) */
1893 };
1894
1895 /* arguments passed to the mmp thread */
1896 struct mmpd_data {
1897         struct buffer_head *bh; /* bh from initial read_mmp_block() */
1898         struct super_block *sb;  /* super block of the fs */
1899 };
1900
1901 /*
1902  * Check interval multiplier
1903  * The MMP block is written every update interval and initially checked every
1904  * update interval x the multiplier (the value is then adapted based on the
1905  * write latency). The reason is that writes can be delayed under load and we
1906  * don't want readers to incorrectly assume that the filesystem is no longer
1907  * in use.
1908  */
1909 #define EXT4_MMP_CHECK_MULT             2UL
1910
1911 /*
1912  * Minimum interval for MMP checking in seconds.
1913  */
1914 #define EXT4_MMP_MIN_CHECK_INTERVAL     5UL
1915
1916 /*
1917  * Maximum interval for MMP checking in seconds.
1918  */
1919 #define EXT4_MMP_MAX_CHECK_INTERVAL     300UL
1920
1921 /*
1922  * Function prototypes
1923  */
1924
1925 /*
1926  * Ok, these declarations are also in <linux/kernel.h> but none of the
1927  * ext4 source programs needs to include it so they are duplicated here.
1928  */
1929 # define NORET_TYPE     /**/
1930 # define ATTRIB_NORET   __attribute__((noreturn))
1931 # define NORET_AND      noreturn,
1932
1933 /* bitmap.c */
1934 extern unsigned int ext4_count_free(char *bitmap, unsigned numchars);
1935 void ext4_inode_bitmap_csum_set(struct super_block *sb, ext4_group_t group,
1936                                 struct ext4_group_desc *gdp,
1937                                 struct buffer_head *bh, int sz);
1938 int ext4_inode_bitmap_csum_verify(struct super_block *sb, ext4_group_t group,
1939                                   struct ext4_group_desc *gdp,
1940                                   struct buffer_head *bh, int sz);
1941 void ext4_block_bitmap_csum_set(struct super_block *sb, ext4_group_t group,
1942                                 struct ext4_group_desc *gdp,
1943                                 struct buffer_head *bh);
1944 int ext4_block_bitmap_csum_verify(struct super_block *sb, ext4_group_t group,
1945                                   struct ext4_group_desc *gdp,
1946                                   struct buffer_head *bh);
1947
1948 /* balloc.c */
1949 extern void ext4_get_group_no_and_offset(struct super_block *sb,
1950                                          ext4_fsblk_t blocknr,
1951                                          ext4_group_t *blockgrpp,
1952                                          ext4_grpblk_t *offsetp);
1953 extern ext4_group_t ext4_get_group_number(struct super_block *sb,
1954                                           ext4_fsblk_t block);
1955
1956 extern unsigned int ext4_block_group(struct super_block *sb,
1957                         ext4_fsblk_t blocknr);
1958 extern ext4_grpblk_t ext4_block_group_offset(struct super_block *sb,
1959                         ext4_fsblk_t blocknr);
1960 extern int ext4_bg_has_super(struct super_block *sb, ext4_group_t group);
1961 extern unsigned long ext4_bg_num_gdb(struct super_block *sb,
1962                         ext4_group_t group);
1963 extern ext4_fsblk_t ext4_new_meta_blocks(handle_t *handle, struct inode *inode,
1964                                          ext4_fsblk_t goal,
1965                                          unsigned int flags,
1966                                          unsigned long *count,
1967                                          int *errp);
1968 extern int ext4_claim_free_clusters(struct ext4_sb_info *sbi,
1969                                     s64 nclusters, unsigned int flags);
1970 extern ext4_fsblk_t ext4_count_free_clusters(struct super_block *);
1971 extern void ext4_check_blocks_bitmap(struct super_block *);
1972 extern struct ext4_group_desc * ext4_get_group_desc(struct super_block * sb,
1973                                                     ext4_group_t block_group,
1974                                                     struct buffer_head ** bh);
1975 extern int ext4_should_retry_alloc(struct super_block *sb, int *retries);
1976
1977 extern struct buffer_head *ext4_read_block_bitmap_nowait(struct super_block *sb,
1978                                                 ext4_group_t block_group);
1979 extern int ext4_wait_block_bitmap(struct super_block *sb,
1980                                   ext4_group_t block_group,
1981                                   struct buffer_head *bh);
1982 extern struct buffer_head *ext4_read_block_bitmap(struct super_block *sb,
1983                                                   ext4_group_t block_group);
1984 extern unsigned ext4_free_clusters_after_init(struct super_block *sb,
1985                                               ext4_group_t block_group,
1986                                               struct ext4_group_desc *gdp);
1987 ext4_fsblk_t ext4_inode_to_goal_block(struct inode *);
1988
1989 /* dir.c */
1990 extern int __ext4_check_dir_entry(const char *, unsigned int, struct inode *,
1991                                   struct file *,
1992                                   struct ext4_dir_entry_2 *,
1993                                   struct buffer_head *, char *, int,
1994                                   unsigned int);
1995 #define ext4_check_dir_entry(dir, filp, de, bh, buf, size, offset)      \
1996         unlikely(__ext4_check_dir_entry(__func__, __LINE__, (dir), (filp), \
1997                                         (de), (bh), (buf), (size), (offset)))
1998 extern int ext4_htree_store_dirent(struct file *dir_file, __u32 hash,
1999                                     __u32 minor_hash,
2000                                     struct ext4_dir_entry_2 *dirent);
2001 extern void ext4_htree_free_dir_info(struct dir_private_info *p);
2002 extern int ext4_find_dest_de(struct inode *dir, struct inode *inode,
2003                              struct buffer_head *bh,
2004                              void *buf, int buf_size,
2005                              const char *name, int namelen,
2006                              struct ext4_dir_entry_2 **dest_de);
2007 void ext4_insert_dentry(struct inode *inode,
2008                         struct ext4_dir_entry_2 *de,
2009                         int buf_size,
2010                         const char *name, int namelen);
2011 static inline void ext4_update_dx_flag(struct inode *inode)
2012 {
2013         if (!EXT4_HAS_COMPAT_FEATURE(inode->i_sb,
2014                                      EXT4_FEATURE_COMPAT_DIR_INDEX))
2015                 ext4_clear_inode_flag(inode, EXT4_INODE_INDEX);
2016 }
2017 static unsigned char ext4_filetype_table[] = {
2018         DT_UNKNOWN, DT_REG, DT_DIR, DT_CHR, DT_BLK, DT_FIFO, DT_SOCK, DT_LNK
2019 };
2020
2021 static inline  unsigned char get_dtype(struct super_block *sb, int filetype)
2022 {
2023         if (!EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_FILETYPE) ||
2024             (filetype >= EXT4_FT_MAX))
2025                 return DT_UNKNOWN;
2026
2027         return ext4_filetype_table[filetype];
2028 }
2029 extern int ext4_check_all_de(struct inode *dir, struct buffer_head *bh,
2030                              void *buf, int buf_size);
2031
2032 /* fsync.c */
2033 extern int ext4_sync_file(struct file *, loff_t, loff_t, int);
2034
2035 /* hash.c */
2036 extern int ext4fs_dirhash(const char *name, int len, struct
2037                           dx_hash_info *hinfo);
2038
2039 /* ialloc.c */
2040 extern struct inode *__ext4_new_inode(handle_t *, struct inode *, umode_t,
2041                                       const struct qstr *qstr, __u32 goal,
2042                                       uid_t *owner, int handle_type,
2043                                       unsigned int line_no, int nblocks);
2044
2045 #define ext4_new_inode(handle, dir, mode, qstr, goal, owner) \
2046         __ext4_new_inode((handle), (dir), (mode), (qstr), (goal), (owner), \
2047                          0, 0, 0)
2048 #define ext4_new_inode_start_handle(dir, mode, qstr, goal, owner, \
2049                                     type, nblocks)                  \
2050         __ext4_new_inode(NULL, (dir), (mode), (qstr), (goal), (owner), \
2051                          (type), __LINE__, (nblocks))
2052
2053
2054 extern void ext4_free_inode(handle_t *, struct inode *);
2055 extern struct inode * ext4_orphan_get(struct super_block *, unsigned long);
2056 extern unsigned long ext4_count_free_inodes(struct super_block *);
2057 extern unsigned long ext4_count_dirs(struct super_block *);
2058 extern void ext4_check_inodes_bitmap(struct super_block *);
2059 extern void ext4_mark_bitmap_end(int start_bit, int end_bit, char *bitmap);
2060 extern int ext4_init_inode_table(struct super_block *sb,
2061                                  ext4_group_t group, int barrier);
2062 extern void ext4_end_bitmap_read(struct buffer_head *bh, int uptodate);
2063
2064 /* mballoc.c */
2065 extern long ext4_mb_stats;
2066 extern long ext4_mb_max_to_scan;
2067 extern int ext4_mb_init(struct super_block *);
2068 extern int ext4_mb_release(struct super_block *);
2069 extern ext4_fsblk_t ext4_mb_new_blocks(handle_t *,
2070                                 struct ext4_allocation_request *, int *);
2071 extern int ext4_mb_reserve_blocks(struct super_block *, int);
2072 extern void ext4_discard_preallocations(struct inode *);
2073 extern int __init ext4_init_mballoc(void);
2074 extern void ext4_exit_mballoc(void);
2075 extern void ext4_free_blocks(handle_t *handle, struct inode *inode,
2076                              struct buffer_head *bh, ext4_fsblk_t block,
2077                              unsigned long count, int flags);
2078 extern int ext4_mb_alloc_groupinfo(struct super_block *sb,
2079                                    ext4_group_t ngroups);
2080 extern int ext4_mb_add_groupinfo(struct super_block *sb,
2081                 ext4_group_t i, struct ext4_group_desc *desc);
2082 extern int ext4_group_add_blocks(handle_t *handle, struct super_block *sb,
2083                                 ext4_fsblk_t block, unsigned long count);
2084 extern int ext4_trim_fs(struct super_block *, struct fstrim_range *);
2085
2086 /* inode.c */
2087 struct buffer_head *ext4_getblk(handle_t *, struct inode *, ext4_lblk_t, int);
2088 struct buffer_head *ext4_bread(handle_t *, struct inode *, ext4_lblk_t, int);
2089 int ext4_get_block_write(struct inode *inode, sector_t iblock,
2090                          struct buffer_head *bh_result, int create);
2091 int ext4_get_block(struct inode *inode, sector_t iblock,
2092                                 struct buffer_head *bh_result, int create);
2093 int ext4_da_get_block_prep(struct inode *inode, sector_t iblock,
2094                            struct buffer_head *bh, int create);
2095 int ext4_walk_page_buffers(handle_t *handle,
2096                            struct buffer_head *head,
2097                            unsigned from,
2098                            unsigned to,
2099                            int *partial,
2100                            int (*fn)(handle_t *handle,
2101                                      struct buffer_head *bh));
2102 int do_journal_get_write_access(handle_t *handle,
2103                                 struct buffer_head *bh);
2104 #define FALL_BACK_TO_NONDELALLOC 1
2105 #define CONVERT_INLINE_DATA      2
2106
2107 extern struct inode *ext4_iget(struct super_block *, unsigned long);
2108 extern struct inode *ext4_iget_normal(struct super_block *, unsigned long);
2109 extern int  ext4_write_inode(struct inode *, struct writeback_control *);
2110 extern int  ext4_setattr(struct dentry *, struct iattr *);
2111 extern int  ext4_getattr(struct vfsmount *mnt, struct dentry *dentry,
2112                                 struct kstat *stat);
2113 extern void ext4_evict_inode(struct inode *);
2114 extern void ext4_clear_inode(struct inode *);
2115 extern int  ext4_sync_inode(handle_t *, struct inode *);
2116 extern void ext4_dirty_inode(struct inode *, int);
2117 extern int ext4_change_inode_journal_flag(struct inode *, int);
2118 extern int ext4_get_inode_loc(struct inode *, struct ext4_iloc *);
2119 extern int ext4_inode_attach_jinode(struct inode *inode);
2120 extern int ext4_can_truncate(struct inode *inode);
2121 extern void ext4_truncate(struct inode *);
2122 extern int ext4_punch_hole(struct inode *inode, loff_t offset, loff_t length);
2123 extern int ext4_truncate_restart_trans(handle_t *, struct inode *, int nblocks);
2124 extern void ext4_set_inode_flags(struct inode *);
2125 extern void ext4_get_inode_flags(struct ext4_inode_info *);
2126 extern int ext4_alloc_da_blocks(struct inode *inode);
2127 extern void ext4_set_aops(struct inode *inode);
2128 extern int ext4_writepage_trans_blocks(struct inode *);
2129 extern int ext4_chunk_trans_blocks(struct inode *, int nrblocks);
2130 extern int ext4_zero_partial_blocks(handle_t *handle, struct inode *inode,
2131                              loff_t lstart, loff_t lend);
2132 extern int ext4_page_mkwrite(struct vm_area_struct *vma, struct vm_fault *vmf);
2133 extern qsize_t *ext4_get_reserved_space(struct inode *inode);
2134 extern void ext4_da_update_reserve_space(struct inode *inode,
2135                                         int used, int quota_claim);
2136
2137 /* indirect.c */
2138 extern int ext4_ind_map_blocks(handle_t *handle, struct inode *inode,
2139                                 struct ext4_map_blocks *map, int flags);
2140 extern ssize_t ext4_ind_direct_IO(int rw, struct kiocb *iocb,
2141                                 struct iov_iter *iter, loff_t offset);
2142 extern int ext4_ind_calc_metadata_amount(struct inode *inode, sector_t lblock);
2143 extern int ext4_ind_trans_blocks(struct inode *inode, int nrblocks);
2144 extern void ext4_ind_truncate(handle_t *, struct inode *inode);
2145 extern int ext4_ind_remove_space(handle_t *handle, struct inode *inode,
2146                                  ext4_lblk_t start, ext4_lblk_t end);
2147
2148 /* ioctl.c */
2149 extern long ext4_ioctl(struct file *, unsigned int, unsigned long);
2150 extern long ext4_compat_ioctl(struct file *, unsigned int, unsigned long);
2151
2152 /* migrate.c */
2153 extern int ext4_ext_migrate(struct inode *);
2154 extern int ext4_ind_migrate(struct inode *inode);
2155
2156 /* namei.c */
2157 extern int ext4_dirent_csum_verify(struct inode *inode,
2158                                    struct ext4_dir_entry *dirent);
2159 extern int ext4_orphan_add(handle_t *, struct inode *);
2160 extern int ext4_orphan_del(handle_t *, struct inode *);
2161 extern int ext4_htree_fill_tree(struct file *dir_file, __u32 start_hash,
2162                                 __u32 start_minor_hash, __u32 *next_hash);
2163 extern int search_dir(struct buffer_head *bh,
2164                       char *search_buf,
2165                       int buf_size,
2166                       struct inode *dir,
2167                       const struct qstr *d_name,
2168                       unsigned int offset,
2169                       struct ext4_dir_entry_2 **res_dir);
2170 extern int ext4_generic_delete_entry(handle_t *handle,
2171                                      struct inode *dir,
2172                                      struct ext4_dir_entry_2 *de_del,
2173                                      struct buffer_head *bh,
2174                                      void *entry_buf,
2175                                      int buf_size,
2176                                      int csum_size);
2177
2178 /* resize.c */
2179 extern int ext4_group_add(struct super_block *sb,
2180                                 struct ext4_new_group_data *input);
2181 extern int ext4_group_extend(struct super_block *sb,
2182                                 struct ext4_super_block *es,
2183                                 ext4_fsblk_t n_blocks_count);
2184 extern int ext4_resize_fs(struct super_block *sb, ext4_fsblk_t n_blocks_count);
2185
2186 /* super.c */
2187 extern int ext4_calculate_overhead(struct super_block *sb);
2188 extern void ext4_superblock_csum_set(struct super_block *sb);
2189 extern void *ext4_kvmalloc(size_t size, gfp_t flags);
2190 extern void *ext4_kvzalloc(size_t size, gfp_t flags);
2191 extern int ext4_alloc_flex_bg_array(struct super_block *sb,
2192                                     ext4_group_t ngroup);
2193 extern const char *ext4_decode_error(struct super_block *sb, int errno,
2194                                      char nbuf[16]);
2195
2196 extern __printf(4, 5)
2197 void __ext4_error(struct super_block *, const char *, unsigned int,
2198                   const char *, ...);
2199 extern __printf(5, 6)
2200 void __ext4_error_inode(struct inode *, const char *, unsigned int, ext4_fsblk_t,
2201                       const char *, ...);
2202 extern __printf(5, 6)
2203 void __ext4_error_file(struct file *, const char *, unsigned int, ext4_fsblk_t,
2204                      const char *, ...);
2205 extern void __ext4_std_error(struct super_block *, const char *,
2206                              unsigned int, int);
2207 extern __printf(4, 5)
2208 void __ext4_abort(struct super_block *, const char *, unsigned int,
2209                   const char *, ...);
2210 extern __printf(4, 5)
2211 void __ext4_warning(struct super_block *, const char *, unsigned int,
2212                     const char *, ...);
2213 extern __printf(3, 4)
2214 void __ext4_msg(struct super_block *, const char *, const char *, ...);
2215 extern void __dump_mmp_msg(struct super_block *, struct mmp_struct *mmp,
2216                            const char *, unsigned int, const char *);
2217 extern __printf(7, 8)
2218 void __ext4_grp_locked_error(const char *, unsigned int,
2219                              struct super_block *, ext4_group_t,
2220                              unsigned long, ext4_fsblk_t,
2221                              const char *, ...);
2222
2223 #ifdef CONFIG_PRINTK
2224
2225 #define ext4_error_inode(inode, func, line, block, fmt, ...)            \
2226         __ext4_error_inode(inode, func, line, block, fmt, ##__VA_ARGS__)
2227 #define ext4_error_file(file, func, line, block, fmt, ...)              \
2228         __ext4_error_file(file, func, line, block, fmt, ##__VA_ARGS__)
2229 #define ext4_error(sb, fmt, ...)                                        \
2230         __ext4_error(sb, __func__, __LINE__, fmt, ##__VA_ARGS__)
2231 #define ext4_abort(sb, fmt, ...)                                        \
2232         __ext4_abort(sb, __func__, __LINE__, fmt, ##__VA_ARGS__)
2233 #define ext4_warning(sb, fmt, ...)                                      \
2234         __ext4_warning(sb, __func__, __LINE__, fmt, ##__VA_ARGS__)
2235 #define ext4_msg(sb, level, fmt, ...)                           \
2236         __ext4_msg(sb, level, fmt, ##__VA_ARGS__)
2237 #define dump_mmp_msg(sb, mmp, msg)                                      \
2238         __dump_mmp_msg(sb, mmp, __func__, __LINE__, msg)
2239 #define ext4_grp_locked_error(sb, grp, ino, block, fmt, ...)            \
2240         __ext4_grp_locked_error(__func__, __LINE__, sb, grp, ino, block, \
2241                                 fmt, ##__VA_ARGS__)
2242
2243 #else
2244
2245 #define ext4_error_inode(inode, func, line, block, fmt, ...)            \
2246 do {                                                                    \
2247         no_printk(fmt, ##__VA_ARGS__);                                  \
2248         __ext4_error_inode(inode, "", 0, block, " ");                   \
2249 } while (0)
2250 #define ext4_error_file(file, func, line, block, fmt, ...)              \
2251 do {                                                                    \
2252         no_printk(fmt, ##__VA_ARGS__);                                  \
2253         __ext4_error_file(file, "", 0, block, " ");                     \
2254 } while (0)
2255 #define ext4_error(sb, fmt, ...)                                        \
2256 do {                                                                    \
2257         no_printk(fmt, ##__VA_ARGS__);                                  \
2258         __ext4_error(sb, "", 0, " ");                                   \
2259 } while (0)
2260 #define ext4_abort(sb, fmt, ...)                                        \
2261 do {                                                                    \
2262         no_printk(fmt, ##__VA_ARGS__);                                  \
2263         __ext4_abort(sb, "", 0, " ");                                   \
2264 } while (0)
2265 #define ext4_warning(sb, fmt, ...)                                      \
2266 do {                                                                    \
2267         no_printk(fmt, ##__VA_ARGS__);                                  \
2268         __ext4_warning(sb, "", 0, " ");                                 \
2269 } while (0)
2270 #define ext4_msg(sb, level, fmt, ...)                                   \
2271 do {                                                                    \
2272         no_printk(fmt, ##__VA_ARGS__);                                  \
2273         __ext4_msg(sb, "", " ");                                        \
2274 } while (0)
2275 #define dump_mmp_msg(sb, mmp, msg)                                      \
2276         __dump_mmp_msg(sb, mmp, "", 0, "")
2277 #define ext4_grp_locked_error(sb, grp, ino, block, fmt, ...)            \
2278 do {                                                                    \
2279         no_printk(fmt, ##__VA_ARGS__);                          \
2280         __ext4_grp_locked_error("", 0, sb, grp, ino, block, " ");       \
2281 } while (0)
2282
2283 #endif
2284
2285 extern void ext4_update_dynamic_rev(struct super_block *sb);
2286 extern int ext4_update_compat_feature(handle_t *handle, struct super_block *sb,
2287                                         __u32 compat);
2288 extern int ext4_update_rocompat_feature(handle_t *handle,
2289                                         struct super_block *sb, __u32 rocompat);
2290 extern int ext4_update_incompat_feature(handle_t *handle,
2291                                         struct super_block *sb, __u32 incompat);
2292 extern ext4_fsblk_t ext4_block_bitmap(struct super_block *sb,
2293                                       struct ext4_group_desc *bg);
2294 extern ext4_fsblk_t ext4_inode_bitmap(struct super_block *sb,
2295                                       struct ext4_group_desc *bg);
2296 extern ext4_fsblk_t ext4_inode_table(struct super_block *sb,
2297                                      struct ext4_group_desc *bg);
2298 extern __u32 ext4_free_group_clusters(struct super_block *sb,
2299                                       struct ext4_group_desc *bg);
2300 extern __u32 ext4_free_inodes_count(struct super_block *sb,
2301                                  struct ext4_group_desc *bg);
2302 extern __u32 ext4_used_dirs_count(struct super_block *sb,
2303                                 struct ext4_group_desc *bg);
2304 extern __u32 ext4_itable_unused_count(struct super_block *sb,
2305                                    struct ext4_group_desc *bg);
2306 extern void ext4_block_bitmap_set(struct super_block *sb,
2307                                   struct ext4_group_desc *bg, ext4_fsblk_t blk);
2308 extern void ext4_inode_bitmap_set(struct super_block *sb,
2309                                   struct ext4_group_desc *bg, ext4_fsblk_t blk);
2310 extern void ext4_inode_table_set(struct super_block *sb,
2311                                  struct ext4_group_desc *bg, ext4_fsblk_t blk);
2312 extern void ext4_free_group_clusters_set(struct super_block *sb,
2313                                          struct ext4_group_desc *bg,
2314                                          __u32 count);
2315 extern void ext4_free_inodes_set(struct super_block *sb,
2316                                 struct ext4_group_desc *bg, __u32 count);
2317 extern void ext4_used_dirs_set(struct super_block *sb,
2318                                 struct ext4_group_desc *bg, __u32 count);
2319 extern void ext4_itable_unused_set(struct super_block *sb,
2320                                    struct ext4_group_desc *bg, __u32 count);
2321 extern int ext4_group_desc_csum_verify(struct super_block *sb, __u32 group,
2322                                        struct ext4_group_desc *gdp);
2323 extern void ext4_group_desc_csum_set(struct super_block *sb, __u32 group,
2324                                      struct ext4_group_desc *gdp);
2325 extern int ext4_register_li_request(struct super_block *sb,
2326                                     ext4_group_t first_not_zeroed);
2327
2328 static inline int ext4_has_group_desc_csum(struct super_block *sb)
2329 {
2330         return EXT4_HAS_RO_COMPAT_FEATURE(sb,
2331                                           EXT4_FEATURE_RO_COMPAT_GDT_CSUM) ||
2332                (EXT4_SB(sb)->s_chksum_driver != NULL);
2333 }
2334
2335 static inline int ext4_has_metadata_csum(struct super_block *sb)
2336 {
2337         WARN_ON_ONCE(EXT4_HAS_RO_COMPAT_FEATURE(sb,
2338                         EXT4_FEATURE_RO_COMPAT_METADATA_CSUM) &&
2339                      !EXT4_SB(sb)->s_chksum_driver);
2340
2341         return (EXT4_SB(sb)->s_chksum_driver != NULL);
2342 }
2343 static inline ext4_fsblk_t ext4_blocks_count(struct ext4_super_block *es)
2344 {
2345         return ((ext4_fsblk_t)le32_to_cpu(es->s_blocks_count_hi) << 32) |
2346                 le32_to_cpu(es->s_blocks_count_lo);
2347 }
2348
2349 static inline ext4_fsblk_t ext4_r_blocks_count(struct ext4_super_block *es)
2350 {
2351         return ((ext4_fsblk_t)le32_to_cpu(es->s_r_blocks_count_hi) << 32) |
2352                 le32_to_cpu(es->s_r_blocks_count_lo);
2353 }
2354
2355 static inline ext4_fsblk_t ext4_free_blocks_count(struct ext4_super_block *es)
2356 {
2357         return ((ext4_fsblk_t)le32_to_cpu(es->s_free_blocks_count_hi) << 32) |
2358                 le32_to_cpu(es->s_free_blocks_count_lo);
2359 }
2360
2361 static inline void ext4_blocks_count_set(struct ext4_super_block *es,
2362                                          ext4_fsblk_t blk)
2363 {
2364         es->s_blocks_count_lo = cpu_to_le32((u32)blk);
2365         es->s_blocks_count_hi = cpu_to_le32(blk >> 32);
2366 }
2367
2368 static inline void ext4_free_blocks_count_set(struct ext4_super_block *es,
2369                                               ext4_fsblk_t blk)
2370 {
2371         es->s_free_blocks_count_lo = cpu_to_le32((u32)blk);
2372         es->s_free_blocks_count_hi = cpu_to_le32(blk >> 32);
2373 }
2374
2375 static inline void ext4_r_blocks_count_set(struct ext4_super_block *es,
2376                                            ext4_fsblk_t blk)
2377 {
2378         es->s_r_blocks_count_lo = cpu_to_le32((u32)blk);
2379         es->s_r_blocks_count_hi = cpu_to_le32(blk >> 32);
2380 }
2381
2382 static inline loff_t ext4_isize(struct ext4_inode *raw_inode)
2383 {
2384         if (S_ISREG(le16_to_cpu(raw_inode->i_mode)))
2385                 return ((loff_t)le32_to_cpu(raw_inode->i_size_high) << 32) |
2386                         le32_to_cpu(raw_inode->i_size_lo);
2387         else
2388                 return (loff_t) le32_to_cpu(raw_inode->i_size_lo);
2389 }
2390
2391 static inline void ext4_isize_set(struct ext4_inode *raw_inode, loff_t i_size)
2392 {
2393         raw_inode->i_size_lo = cpu_to_le32(i_size);
2394         raw_inode->i_size_high = cpu_to_le32(i_size >> 32);
2395 }
2396
2397 static inline
2398 struct ext4_group_info *ext4_get_group_info(struct super_block *sb,
2399                                             ext4_group_t group)
2400 {
2401          struct ext4_group_info ***grp_info;
2402          long indexv, indexh;
2403          BUG_ON(group >= EXT4_SB(sb)->s_groups_count);
2404          grp_info = EXT4_SB(sb)->s_group_info;
2405          indexv = group >> (EXT4_DESC_PER_BLOCK_BITS(sb));
2406          indexh = group & ((EXT4_DESC_PER_BLOCK(sb)) - 1);
2407          return grp_info[indexv][indexh];
2408 }
2409
2410 /*
2411  * Reading s_groups_count requires using smp_rmb() afterwards.  See
2412  * the locking protocol documented in the comments of ext4_group_add()
2413  * in resize.c
2414  */
2415 static inline ext4_group_t ext4_get_groups_count(struct super_block *sb)
2416 {
2417         ext4_group_t    ngroups = EXT4_SB(sb)->s_groups_count;
2418
2419         smp_rmb();
2420         return ngroups;
2421 }
2422
2423 static inline ext4_group_t ext4_flex_group(struct ext4_sb_info *sbi,
2424                                              ext4_group_t block_group)
2425 {
2426         return block_group >> sbi->s_log_groups_per_flex;
2427 }
2428
2429 static inline unsigned int ext4_flex_bg_size(struct ext4_sb_info *sbi)
2430 {
2431         return 1 << sbi->s_log_groups_per_flex;
2432 }
2433
2434 #define ext4_std_error(sb, errno)                               \
2435 do {                                                            \
2436         if ((errno))                                            \
2437                 __ext4_std_error((sb), __func__, __LINE__, (errno));    \
2438 } while (0)
2439
2440 #ifdef CONFIG_SMP
2441 /* Each CPU can accumulate percpu_counter_batch clusters in their local
2442  * counters. So we need to make sure we have free clusters more
2443  * than percpu_counter_batch  * nr_cpu_ids. Also add a window of 4 times.
2444  */
2445 #define EXT4_FREECLUSTERS_WATERMARK (4 * (percpu_counter_batch * nr_cpu_ids))
2446 #else
2447 #define EXT4_FREECLUSTERS_WATERMARK 0
2448 #endif
2449
2450 /* Update i_disksize. Requires i_mutex to avoid races with truncate */
2451 static inline void ext4_update_i_disksize(struct inode *inode, loff_t newsize)
2452 {
2453         WARN_ON_ONCE(S_ISREG(inode->i_mode) &&
2454                      !mutex_is_locked(&inode->i_mutex));
2455         down_write(&EXT4_I(inode)->i_data_sem);
2456         if (newsize > EXT4_I(inode)->i_disksize)
2457                 EXT4_I(inode)->i_disksize = newsize;
2458         up_write(&EXT4_I(inode)->i_data_sem);
2459 }
2460
2461 /* Update i_size, i_disksize. Requires i_mutex to avoid races with truncate */
2462 static inline int ext4_update_inode_size(struct inode *inode, loff_t newsize)
2463 {
2464         int changed = 0;
2465
2466         if (newsize > inode->i_size) {
2467                 i_size_write(inode, newsize);
2468                 changed = 1;
2469         }
2470         if (newsize > EXT4_I(inode)->i_disksize) {
2471                 ext4_update_i_disksize(inode, newsize);
2472                 changed |= 2;
2473         }
2474         return changed;
2475 }
2476
2477 struct ext4_group_info {
2478         unsigned long   bb_state;
2479         struct rb_root  bb_free_root;
2480         ext4_grpblk_t   bb_first_free;  /* first free block */
2481         ext4_grpblk_t   bb_free;        /* total free blocks */
2482         ext4_grpblk_t   bb_fragments;   /* nr of freespace fragments */
2483         ext4_grpblk_t   bb_largest_free_order;/* order of largest frag in BG */
2484         struct          list_head bb_prealloc_list;
2485 #ifdef DOUBLE_CHECK
2486         void            *bb_bitmap;
2487 #endif
2488         struct rw_semaphore alloc_sem;
2489         ext4_grpblk_t   bb_counters[];  /* Nr of free power-of-two-block
2490                                          * regions, index is order.
2491                                          * bb_counters[3] = 5 means
2492                                          * 5 free 8-block regions. */
2493 };
2494
2495 #define EXT4_GROUP_INFO_NEED_INIT_BIT           0
2496 #define EXT4_GROUP_INFO_WAS_TRIMMED_BIT         1
2497 #define EXT4_GROUP_INFO_BBITMAP_CORRUPT_BIT     2
2498 #define EXT4_GROUP_INFO_IBITMAP_CORRUPT_BIT     3
2499
2500 #define EXT4_MB_GRP_NEED_INIT(grp)      \
2501         (test_bit(EXT4_GROUP_INFO_NEED_INIT_BIT, &((grp)->bb_state)))
2502 #define EXT4_MB_GRP_BBITMAP_CORRUPT(grp)        \
2503         (test_bit(EXT4_GROUP_INFO_BBITMAP_CORRUPT_BIT, &((grp)->bb_state)))
2504 #define EXT4_MB_GRP_IBITMAP_CORRUPT(grp)        \
2505         (test_bit(EXT4_GROUP_INFO_IBITMAP_CORRUPT_BIT, &((grp)->bb_state)))
2506
2507 #define EXT4_MB_GRP_WAS_TRIMMED(grp)    \
2508         (test_bit(EXT4_GROUP_INFO_WAS_TRIMMED_BIT, &((grp)->bb_state)))
2509 #define EXT4_MB_GRP_SET_TRIMMED(grp)    \
2510         (set_bit(EXT4_GROUP_INFO_WAS_TRIMMED_BIT, &((grp)->bb_state)))
2511 #define EXT4_MB_GRP_CLEAR_TRIMMED(grp)  \
2512         (clear_bit(EXT4_GROUP_INFO_WAS_TRIMMED_BIT, &((grp)->bb_state)))
2513
2514 #define EXT4_MAX_CONTENTION             8
2515 #define EXT4_CONTENTION_THRESHOLD       2
2516
2517 static inline spinlock_t *ext4_group_lock_ptr(struct super_block *sb,
2518                                               ext4_group_t group)
2519 {
2520         return bgl_lock_ptr(EXT4_SB(sb)->s_blockgroup_lock, group);
2521 }
2522
2523 /*
2524  * Returns true if the filesystem is busy enough that attempts to
2525  * access the block group locks has run into contention.
2526  */
2527 static inline int ext4_fs_is_busy(struct ext4_sb_info *sbi)
2528 {
2529         return (atomic_read(&sbi->s_lock_busy) > EXT4_CONTENTION_THRESHOLD);
2530 }
2531
2532 static inline void ext4_lock_group(struct super_block *sb, ext4_group_t group)
2533 {
2534         spinlock_t *lock = ext4_group_lock_ptr(sb, group);
2535         if (spin_trylock(lock))
2536                 /*
2537                  * We're able to grab the lock right away, so drop the
2538                  * lock contention counter.
2539                  */
2540                 atomic_add_unless(&EXT4_SB(sb)->s_lock_busy, -1, 0);
2541         else {
2542                 /*
2543                  * The lock is busy, so bump the contention counter,
2544                  * and then wait on the spin lock.
2545                  */
2546                 atomic_add_unless(&EXT4_SB(sb)->s_lock_busy, 1,
2547                                   EXT4_MAX_CONTENTION);
2548                 spin_lock(lock);
2549         }
2550 }
2551
2552 static inline void ext4_unlock_group(struct super_block *sb,
2553                                         ext4_group_t group)
2554 {
2555         spin_unlock(ext4_group_lock_ptr(sb, group));
2556 }
2557
2558 /*
2559  * Block validity checking
2560  */
2561 #define ext4_check_indirect_blockref(inode, bh)                         \
2562         ext4_check_blockref(__func__, __LINE__, inode,                  \
2563                             (__le32 *)(bh)->b_data,                     \
2564                             EXT4_ADDR_PER_BLOCK((inode)->i_sb))
2565
2566 #define ext4_ind_check_inode(inode)                                     \
2567         ext4_check_blockref(__func__, __LINE__, inode,                  \
2568                             EXT4_I(inode)->i_data,                      \
2569                             EXT4_NDIR_BLOCKS)
2570
2571 /*
2572  * Inodes and files operations
2573  */
2574
2575 /* dir.c */
2576 extern const struct file_operations ext4_dir_operations;
2577
2578 /* file.c */
2579 extern const struct inode_operations ext4_file_inode_operations;
2580 extern const struct file_operations ext4_file_operations;
2581 extern loff_t ext4_llseek(struct file *file, loff_t offset, int origin);
2582
2583 /* inline.c */
2584 extern int ext4_get_max_inline_size(struct inode *inode);
2585 extern int ext4_find_inline_data_nolock(struct inode *inode);
2586 extern int ext4_init_inline_data(handle_t *handle, struct inode *inode,
2587                                  unsigned int len);
2588 extern int ext4_destroy_inline_data(handle_t *handle, struct inode *inode);
2589
2590 extern int ext4_readpage_inline(struct inode *inode, struct page *page);
2591 extern int ext4_try_to_write_inline_data(struct address_space *mapping,
2592                                          struct inode *inode,
2593                                          loff_t pos, unsigned len,
2594                                          unsigned flags,
2595                                          struct page **pagep);
2596 extern int ext4_write_inline_data_end(struct inode *inode,
2597                                       loff_t pos, unsigned len,
2598                                       unsigned copied,
2599                                       struct page *page);
2600 extern struct buffer_head *
2601 ext4_journalled_write_inline_data(struct inode *inode,
2602                                   unsigned len,
2603                                   struct page *page);
2604 extern int ext4_da_write_inline_data_begin(struct address_space *mapping,
2605                                            struct inode *inode,
2606                                            loff_t pos, unsigned len,
2607                                            unsigned flags,
2608                                            struct page **pagep,
2609                                            void **fsdata);
2610 extern int ext4_da_write_inline_data_end(struct inode *inode, loff_t pos,
2611                                          unsigned len, unsigned copied,
2612                                          struct page *page);
2613 extern int ext4_try_add_inline_entry(handle_t *handle, struct dentry *dentry,
2614                                      struct inode *inode);
2615 extern int ext4_try_create_inline_dir(handle_t *handle,
2616                                       struct inode *parent,
2617                                       struct inode *inode);
2618 extern int ext4_read_inline_dir(struct file *filp,
2619                                 struct dir_context *ctx,
2620                                 int *has_inline_data);
2621 extern int htree_inlinedir_to_tree(struct file *dir_file,
2622                                    struct inode *dir, ext4_lblk_t block,
2623                                    struct dx_hash_info *hinfo,
2624                                    __u32 start_hash, __u32 start_minor_hash,
2625                                    int *has_inline_data);
2626 extern struct buffer_head *ext4_find_inline_entry(struct inode *dir,
2627                                         const struct qstr *d_name,
2628                                         struct ext4_dir_entry_2 **res_dir,
2629                                         int *has_inline_data);
2630 extern int ext4_delete_inline_entry(handle_t *handle,
2631                                     struct inode *dir,
2632                                     struct ext4_dir_entry_2 *de_del,
2633                                     struct buffer_head *bh,
2634                                     int *has_inline_data);
2635 extern int empty_inline_dir(struct inode *dir, int *has_inline_data);
2636 extern struct buffer_head *ext4_get_first_inline_block(struct inode *inode,
2637                                         struct ext4_dir_entry_2 **parent_de,
2638                                         int *retval);
2639 extern int ext4_inline_data_fiemap(struct inode *inode,
2640                                    struct fiemap_extent_info *fieinfo,
2641                                    int *has_inline, __u64 start, __u64 len);
2642 extern int ext4_try_to_evict_inline_data(handle_t *handle,
2643                                          struct inode *inode,
2644                                          int needed);
2645 extern void ext4_inline_data_truncate(struct inode *inode, int *has_inline);
2646
2647 extern int ext4_convert_inline_data(struct inode *inode);
2648
2649 static inline int ext4_has_inline_data(struct inode *inode)
2650 {
2651         return ext4_test_inode_flag(inode, EXT4_INODE_INLINE_DATA) &&
2652                EXT4_I(inode)->i_inline_off;
2653 }
2654
2655 /* namei.c */
2656 extern const struct inode_operations ext4_dir_inode_operations;
2657 extern const struct inode_operations ext4_special_inode_operations;
2658 extern struct dentry *ext4_get_parent(struct dentry *child);
2659 extern struct ext4_dir_entry_2 *ext4_init_dot_dotdot(struct inode *inode,
2660                                  struct ext4_dir_entry_2 *de,
2661                                  int blocksize, int csum_size,
2662                                  unsigned int parent_ino, int dotdot_real_len);
2663 extern void initialize_dirent_tail(struct ext4_dir_entry_tail *t,
2664                                    unsigned int blocksize);
2665 extern int ext4_handle_dirty_dirent_node(handle_t *handle,
2666                                          struct inode *inode,
2667                                          struct buffer_head *bh);
2668 #define S_SHIFT 12
2669 static unsigned char ext4_type_by_mode[S_IFMT >> S_SHIFT] = {
2670         [S_IFREG >> S_SHIFT]    = EXT4_FT_REG_FILE,
2671         [S_IFDIR >> S_SHIFT]    = EXT4_FT_DIR,
2672         [S_IFCHR >> S_SHIFT]    = EXT4_FT_CHRDEV,
2673         [S_IFBLK >> S_SHIFT]    = EXT4_FT_BLKDEV,
2674         [S_IFIFO >> S_SHIFT]    = EXT4_FT_FIFO,
2675         [S_IFSOCK >> S_SHIFT]   = EXT4_FT_SOCK,
2676         [S_IFLNK >> S_SHIFT]    = EXT4_FT_SYMLINK,
2677 };
2678
2679 static inline void ext4_set_de_type(struct super_block *sb,
2680                                 struct ext4_dir_entry_2 *de,
2681                                 umode_t mode) {
2682         if (EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_FILETYPE))
2683                 de->file_type = ext4_type_by_mode[(mode & S_IFMT)>>S_SHIFT];
2684 }
2685
2686
2687 /* symlink.c */
2688 extern const struct inode_operations ext4_symlink_inode_operations;
2689 extern const struct inode_operations ext4_fast_symlink_inode_operations;
2690
2691 /* block_validity */
2692 extern void ext4_release_system_zone(struct super_block *sb);
2693 extern int ext4_setup_system_zone(struct super_block *sb);
2694 extern int __init ext4_init_system_zone(void);
2695 extern void ext4_exit_system_zone(void);
2696 extern int ext4_data_block_valid(struct ext4_sb_info *sbi,
2697                                  ext4_fsblk_t start_blk,
2698                                  unsigned int count);
2699 extern int ext4_check_blockref(const char *, unsigned int,
2700                                struct inode *, __le32 *, unsigned int);
2701
2702 /* extents.c */
2703 struct ext4_ext_path;
2704 struct ext4_extent;
2705
2706 /*
2707  * Maximum number of logical blocks in a file; ext4_extent's ee_block is
2708  * __le32.
2709  */
2710 #define EXT_MAX_BLOCKS  0xffffffff
2711
2712 extern int ext4_ext_tree_init(handle_t *handle, struct inode *);
2713 extern int ext4_ext_writepage_trans_blocks(struct inode *, int);
2714 extern int ext4_ext_index_trans_blocks(struct inode *inode, int extents);
2715 extern int ext4_ext_map_blocks(handle_t *handle, struct inode *inode,
2716                                struct ext4_map_blocks *map, int flags);
2717 extern void ext4_ext_truncate(handle_t *, struct inode *);
2718 extern int ext4_ext_remove_space(struct inode *inode, ext4_lblk_t start,
2719                                  ext4_lblk_t end);
2720 extern void ext4_ext_init(struct super_block *);
2721 extern void ext4_ext_release(struct super_block *);
2722 extern long ext4_fallocate(struct file *file, int mode, loff_t offset,
2723                           loff_t len);
2724 extern int ext4_convert_unwritten_extents(handle_t *handle, struct inode *inode,
2725                                           loff_t offset, ssize_t len);
2726 extern int ext4_map_blocks(handle_t *handle, struct inode *inode,
2727                            struct ext4_map_blocks *map, int flags);
2728 extern int ext4_ext_calc_metadata_amount(struct inode *inode,
2729                                          ext4_lblk_t lblocks);
2730 extern int ext4_extent_tree_init(handle_t *, struct inode *);
2731 extern int ext4_ext_calc_credits_for_single_extent(struct inode *inode,
2732                                                    int num,
2733                                                    struct ext4_ext_path *path);
2734 extern int ext4_can_extents_be_merged(struct inode *inode,
2735                                       struct ext4_extent *ex1,
2736                                       struct ext4_extent *ex2);
2737 extern int ext4_ext_insert_extent(handle_t *, struct inode *,
2738                                   struct ext4_ext_path **,
2739                                   struct ext4_extent *, int);
2740 extern struct ext4_ext_path *ext4_find_extent(struct inode *, ext4_lblk_t,
2741                                               struct ext4_ext_path **,
2742                                               int flags);
2743 extern void ext4_ext_drop_refs(struct ext4_ext_path *);
2744 extern int ext4_ext_check_inode(struct inode *inode);
2745 extern int ext4_find_delalloc_range(struct inode *inode,
2746                                     ext4_lblk_t lblk_start,
2747                                     ext4_lblk_t lblk_end);
2748 extern int ext4_find_delalloc_cluster(struct inode *inode, ext4_lblk_t lblk);
2749 extern ext4_lblk_t ext4_ext_next_allocated_block(struct ext4_ext_path *path);
2750 extern int ext4_fiemap(struct inode *inode, struct fiemap_extent_info *fieinfo,
2751                         __u64 start, __u64 len);
2752 extern int ext4_ext_precache(struct inode *inode);
2753 extern int ext4_collapse_range(struct inode *inode, loff_t offset, loff_t len);
2754 extern int ext4_swap_extents(handle_t *handle, struct inode *inode1,
2755                                 struct inode *inode2, ext4_lblk_t lblk1,
2756                              ext4_lblk_t lblk2,  ext4_lblk_t count,
2757                              int mark_unwritten,int *err);
2758
2759 /* move_extent.c */
2760 extern void ext4_double_down_write_data_sem(struct inode *first,
2761                                             struct inode *second);
2762 extern void ext4_double_up_write_data_sem(struct inode *orig_inode,
2763                                           struct inode *donor_inode);
2764 extern int ext4_move_extents(struct file *o_filp, struct file *d_filp,
2765                              __u64 start_orig, __u64 start_donor,
2766                              __u64 len, __u64 *moved_len);
2767
2768 /* page-io.c */
2769 extern int __init ext4_init_pageio(void);
2770 extern void ext4_exit_pageio(void);
2771 extern ext4_io_end_t *ext4_init_io_end(struct inode *inode, gfp_t flags);
2772 extern ext4_io_end_t *ext4_get_io_end(ext4_io_end_t *io_end);
2773 extern int ext4_put_io_end(ext4_io_end_t *io_end);
2774 extern void ext4_put_io_end_defer(ext4_io_end_t *io_end);
2775 extern void ext4_io_submit_init(struct ext4_io_submit *io,
2776                                 struct writeback_control *wbc);
2777 extern void ext4_end_io_rsv_work(struct work_struct *work);
2778 extern void ext4_io_submit(struct ext4_io_submit *io);
2779 extern int ext4_bio_write_page(struct ext4_io_submit *io,
2780                                struct page *page,
2781                                int len,
2782                                struct writeback_control *wbc,
2783                                bool keep_towrite);
2784
2785 /* mmp.c */
2786 extern int ext4_multi_mount_protect(struct super_block *, ext4_fsblk_t);
2787
2788 /*
2789  * Add new method to test whether block and inode bitmaps are properly
2790  * initialized. With uninit_bg reading the block from disk is not enough
2791  * to mark the bitmap uptodate. We need to also zero-out the bitmap
2792  */
2793 #define BH_BITMAP_UPTODATE BH_JBDPrivateStart
2794
2795 static inline int bitmap_uptodate(struct buffer_head *bh)
2796 {
2797         return (buffer_uptodate(bh) &&
2798                         test_bit(BH_BITMAP_UPTODATE, &(bh)->b_state));
2799 }
2800 static inline void set_bitmap_uptodate(struct buffer_head *bh)
2801 {
2802         set_bit(BH_BITMAP_UPTODATE, &(bh)->b_state);
2803 }
2804
2805 /*
2806  * Disable DIO read nolock optimization, so new dioreaders will be forced
2807  * to grab i_mutex
2808  */
2809 static inline void ext4_inode_block_unlocked_dio(struct inode *inode)
2810 {
2811         ext4_set_inode_state(inode, EXT4_STATE_DIOREAD_LOCK);
2812         smp_mb();
2813 }
2814 static inline void ext4_inode_resume_unlocked_dio(struct inode *inode)
2815 {
2816         smp_mb();
2817         ext4_clear_inode_state(inode, EXT4_STATE_DIOREAD_LOCK);
2818 }
2819
2820 #define in_range(b, first, len) ((b) >= (first) && (b) <= (first) + (len) - 1)
2821
2822 /* For ioend & aio unwritten conversion wait queues */
2823 #define EXT4_WQ_HASH_SZ         37
2824 #define ext4_ioend_wq(v)   (&ext4__ioend_wq[((unsigned long)(v)) %\
2825                                             EXT4_WQ_HASH_SZ])
2826 #define ext4_aio_mutex(v)  (&ext4__aio_mutex[((unsigned long)(v)) %\
2827                                              EXT4_WQ_HASH_SZ])
2828 extern wait_queue_head_t ext4__ioend_wq[EXT4_WQ_HASH_SZ];
2829 extern struct mutex ext4__aio_mutex[EXT4_WQ_HASH_SZ];
2830
2831 #define EXT4_RESIZING   0
2832 extern int ext4_resize_begin(struct super_block *sb);
2833 extern void ext4_resize_end(struct super_block *sb);
2834
2835 #endif  /* __KERNEL__ */
2836
2837 #endif  /* _EXT4_H */